WorldWideScience

Sample records for performance detection rate

  1. A High Performance Impedance-based Platform for Evaporation Rate Detection.

    Science.gov (United States)

    Chou, Wei-Lung; Lee, Pee-Yew; Chen, Cheng-You; Lin, Yu-Hsin; Lin, Yung-Sheng

    2016-10-17

    This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was employed here for demonstration purposes. Multiple evaporation tests on the model compound as a humectant with various concentrations in solutions were conducted for comparison purposes. A conventional weight loss approach is known as the most straightforward, but time-consuming, measurement technique for evaporation rate detection. Yet, a clear disadvantage is that a large volume of sample is required and multiple sample tests cannot be conducted at the same time. For the first time in literature, an electrical impedance sensing chip is successfully applied to a real-time evaporation investigation in a time sharing, continuous and automatic manner. Moreover, as little as 0.5 ml of test samples is required in this impedance-based apparatus, and a large impedance variation is demonstrated among various dilute solutions. The proposed high-sensitivity and fast-response impedance sensing system is found to outperform a conventional weight loss approach in terms of evaporation rate detection.

  2. Error rate performance of narrowband multilevel CPFSK signals

    Science.gov (United States)

    Ekanayake, N.; Fonseka, K. J. P.

    1987-04-01

    The paper presents a relatively simple method for analyzing the effect of IF filtering on the performance of multilevel FM signals. Using this method, the error rate performance of narrowband FM signals is analyzed for three different detection techniques, namely limiter-discriminator detection, differential detection and coherent detection followed by differential decoding. The symbol error probabilities are computed for a Gaussian IF filter and a second-order Butterworth IF filter. It is shown that coherent detection and differential decoding yields better performance than limiter-discriminator detection and differential detection, whereas two noncoherent detectors yield approximately identical performance.

  3. Arduino-based noise robust online heart-rate detection.

    Science.gov (United States)

    Das, Sangita; Pal, Saurabh; Mitra, Madhuchhanda

    2017-04-01

    This paper introduces a noise robust real time heart rate detection system from electrocardiogram (ECG) data. An online data acquisition system is developed to collect ECG signals from human subjects. Heart rate is detected using window-based autocorrelation peak localisation technique. A low-cost Arduino UNO board is used to implement the complete automated process. The performance of the system is compared with PC-based heart rate detection technique. Accuracy of the system is validated through simulated noisy ECG data with various levels of signal to noise ratio (SNR). The mean percentage error of detected heart rate is found to be 0.72% for the noisy database with five different noise levels.

  4. Computer-aided detection of pulmonary nodules: influence of nodule characteristics on detection performance

    International Nuclear Information System (INIS)

    Marten, K.; Engelke, C.; Seyfarth, T.; Grillhoesl, A.; Obenauer, S.; Rummeny, E.J.

    2005-01-01

    AIM: To evaluate prospectively the influence of pulmonary nodule characteristics on detection performances of a computer-aided diagnosis (CAD) tool and experienced chest radiologists using multislice CT (MSCT). MATERIALS AND METHODS: MSCT scans of 20 consecutive patients were evaluated by a CAD system and two independent chest radiologists for presence of pulmonary nodules. Nodule size, position, margin, matrix characteristics, vascular and pleural attachments and reader confidence were recorded and data compared with an independent standard of reference. Statistical analysis for predictors influencing nodule detection or reader performance included chi-squared, retrograde stepwise conditional logistic regression with odds ratios and nodule detection proportion estimates (DPE), and ROC analysis. RESULTS: For 135 nodules, detection rates for CAD and readers were 76.3, 52.6 and 52.6%, respectively; false-positive rates were 0.55, 0.25 and 0.15 per examination, respectively. In consensus with CAD the reader detection rate increased to 93.3%, and the false-positive rate dropped to 0.1/scan. DPEs for nodules ≤5 mm were significantly higher for ICAD than for the readers (p<0.05). Absence of vascular attachment was the only significant predictor of nodule detection by CAD (p=0.0006-0.008). There were no predictors of nodule detection for reader consensus with CAD. In contrast, vascular attachment predicted nodule detection by the readers (p=0.0001-0.003). Reader sensitivity was higher for nodules with vascular attachment than for unattached nodules (sensitivities 0.768 and 0.369; 95% confidence intervals=0.651-0.861 and 0.253-0.498, respectively). CONCLUSION: CAD increases nodule detection rates, decreases false-positive rates and compensates for deficient reader performance in detection of smallest lesions and of nodules without vascular attachment

  5. Bit-error-rate performance analysis of self-heterodyne detected radio-over-fiber links using phase and intensity modulation

    DEFF Research Database (Denmark)

    Yin, Xiaoli; Yu, Xianbin; Tafur Monroy, Idelfonso

    2010-01-01

    We theoretically and experimentally investigate the performance of two self-heterodyne detected radio-over-fiber (RoF) links employing phase modulation (PM) and quadrature biased intensity modulation (IM), in term of bit-error-rate (BER) and optical signal-to-noise-ratio (OSNR). In both links, self...

  6. Factors influencing variation in physician adenoma detection rates: a theory-based approach for performance improvement.

    Science.gov (United States)

    Atkins, Louise; Hunkeler, Enid M; Jensen, Christopher D; Michie, Susan; Lee, Jeffrey K; Doubeni, Chyke A; Zauber, Ann G; Levin, Theodore R; Quinn, Virginia P; Corley, Douglas A

    2016-03-01

    Interventions to improve physician adenoma detection rates for colonoscopy have generally not been successful, and there are little data on the factors contributing to variation that may be appropriate targets for intervention. We sought to identify factors that may influence variation in detection rates by using theory-based tools for understanding behavior. We separately studied gastroenterologists and endoscopy nurses at 3 Kaiser Permanente Northern California medical centers to identify potentially modifiable factors relevant to physician adenoma detection rate variability by using structured group interviews (focus groups) and theory-based tools for understanding behavior and eliciting behavior change: the Capability, Opportunity, and Motivation behavior model; the Theoretical Domains Framework; and the Behavior Change Wheel. Nine factors potentially associated with adenoma detection rate variability were identified, including 6 related to capability (uncertainty about which types of polyps to remove, style of endoscopy team leadership, compromised ability to focus during an examination due to distractions, examination technique during withdrawal, difficulty detecting certain types of adenomas, and examiner fatigue and pain), 2 related to opportunity (perceived pressure due to the number of examinations expected per shift and social pressure to finish examinations before scheduled breaks or the end of a shift), and 1 related to motivation (valuing a meticulous examination as the top priority). Examples of potential intervention strategies are provided. By using theory-based tools, this study identified several novel and potentially modifiable factors relating to capability, opportunity, and motivation that may contribute to adenoma detection rate variability and be appropriate targets for future intervention trials. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  7. Novel Fingertip Image-Based Heart Rate Detection Methods for a Smartphone

    Directory of Open Access Journals (Sweden)

    Rifat Zaman

    2017-02-01

    Full Text Available We hypothesize that our fingertip image-based heart rate detection methods using smartphone reliably detect the heart rhythm and rate of subjects. We propose fingertip curve line movement-based and fingertip image intensity-based detection methods, which both use the movement of successive fingertip images obtained from smartphone cameras. To investigate the performance of the proposed methods, heart rhythm and rate of the proposed methods are compared to those of the conventional method, which is based on average image pixel intensity. Using a smartphone, we collected 120 s pulsatile time series data from each recruited subject. The results show that the proposed fingertip curve line movement-based method detects heart rate with a maximum deviation of 0.0832 Hz and 0.124 Hz using time- and frequency-domain based estimation, respectively, compared to the conventional method. Moreover, another proposed fingertip image intensity-based method detects heart rate with a maximum deviation of 0.125 Hz and 0.03 Hz using time- and frequency-based estimation, respectively.

  8. Rate based failure detection

    Science.gov (United States)

    Johnson, Brett Emery Trabun; Gamage, Thoshitha Thanushka; Bakken, David Edward

    2018-01-02

    This disclosure describes, in part, a system management component and failure detection component for use in a power grid data network to identify anomalies within the network and systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription. The failure detection component may identify an anomaly within the network and a source of the anomaly. Based on the identified anomaly, data rates and or data paths may be adjusted in real-time to ensure that the power grid data network does not become overloaded and/or fail.

  9. Detection Performance of Packet Arrival under Downclocking for Mobile Edge Computing

    Directory of Open Access Journals (Sweden)

    Zhimin Wang

    2018-01-01

    Full Text Available Mobile edge computing (MEC enables battery-powered mobile nodes to acquire information technology services at the network edge. These nodes desire to enjoy their service under power saving. The sampling rate invariant detection (SRID is the first downclocking WiFi technique that can achieve this objective. With SRID, a node detects one packet arrival at a downclocked rate. Upon a successful detection, the node reverts to a full-clocked rate to receive the packet immediately. To ensure that a node acquires its service immediately, the detection performance (namely, the miss-detection probability and the false-alarm probability of SRID is of importance. This paper is the first one to theoretically study the crucial impact of SRID attributes (e.g., tolerance threshold, correlation threshold, and energy ratio threshold on the packet detection performance. Extensive Monte Carlo experiments show that our theoretical model is very accurate. This study can help system developers set reasonable system parameters for WiFi downclocking.

  10. Application of a conversion factor to estimate the adenoma detection rate from the polyp detection rate.

    LENUS (Irish Health Repository)

    Francis, Dawn L

    2011-03-01

    The adenoma detection rate (ADR) is a quality benchmark for colonoscopy. Many practices find it difficult to determine the ADR because it requires a combination of endoscopic and histologic findings. It may be possible to apply a conversion factor to estimate the ADR from the polyp detection rate (PDR).

  11. Pipe fracture evaluations for leak-rate detection: Probabilistic models

    International Nuclear Information System (INIS)

    Rahman, S.; Wilkowski, G.; Ghadiali, N.

    1993-01-01

    This is the second in series of three papers generated from studies on nuclear pipe fracture evaluations for leak-rate detection. This paper focuses on the development of novel probabilistic models for stochastic performance evaluation of degraded nuclear piping systems. It was accomplished here in three distinct stages. First, a statistical analysis was conducted to characterize various input variables for thermo-hydraulic analysis and elastic-plastic fracture mechanics, such as material properties of pipe, crack morphology variables, and location of cracks found in nuclear piping. Second, a new stochastic model was developed to evaluate performance of degraded piping systems. It is based on accurate deterministic models for thermo-hydraulic and fracture mechanics analyses described in the first paper, statistical characterization of various input variables, and state-of-the-art methods of modem structural reliability theory. From this model. the conditional probability of failure as a function of leak-rate detection capability of the piping systems can be predicted. Third, a numerical example was presented to illustrate the proposed model for piping reliability analyses. Results clearly showed that the model provides satisfactory estimates of conditional failure probability with much less computational effort when compared with those obtained from Monte Carlo simulation. The probabilistic model developed in this paper will be applied to various piping in boiling water reactor and pressurized water reactor plants for leak-rate detection applications

  12. Probabilistic pipe fracture evaluations for leak-rate-detection applications

    International Nuclear Information System (INIS)

    Rahman, S.; Ghadiali, N.; Paul, D.; Wilkowski, G.

    1995-04-01

    Regulatory Guide 1.45, open-quotes Reactor Coolant Pressure Boundary Leakage Detection Systems,close quotes was published by the U.S. Nuclear Regulatory Commission (NRC) in May 1973, and provides guidance on leak detection methods and system requirements for Light Water Reactors. Additionally, leak detection limits are specified in plant Technical Specifications and are different for Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). These leak detection limits are also used in leak-before-break evaluations performed in accordance with Draft Standard Review Plan, Section 3.6.3, open-quotes Leak Before Break Evaluation Proceduresclose quotes where a margin of 10 on the leak detection limit is used in determining the crack size considered in subsequent fracture analyses. This study was requested by the NRC to: (1) evaluate the conditional failure probability for BWR and PWR piping for pipes that were leaking at the allowable leak detection limit, and (2) evaluate the margin of 10 to determine if it was unnecessarily large. A probabilistic approach was undertaken to conduct fracture evaluations of circumferentially cracked pipes for leak-rate-detection applications. Sixteen nuclear piping systems in BWR and PWR plants were analyzed to evaluate conditional failure probability and effects of crack-morphology variability on the current margins used in leak rate detection for leak-before-break

  13. Detection of sentinel lymph node in breast cancer and malignant melanoma - Influence of some factors on detection success rate

    International Nuclear Information System (INIS)

    Krafta, O.; Safarcika, K.; Stepien, A.

    2004-01-01

    Full text: The aim of this study was to compare three radiopharmaceuticals for sentinel lymph node detection in breast cancer and malignant melanoma patients. We examined 100 women and 2 men with breast cancer (average age 59.3 years) and 167 patients with malignant melanoma (69 men with mean age of 58.6 years and 98 women with mean age of 53.6 years). Lymphoscintigraphy was performed in all patients after injection of the radiotracer, either of the three: NANOCIS (average particle size 100 nm), SENTISCINT (particle size 100-600 nm), and NANOCOLL (particle size under 80 nm). Dynamic scintigraphy was performed in melanoma patients while breast cancer patients were subjected to stating imaging at 1-2 and 22 hours of injection. In patients with melanoma surgery was done on the same day, to remove the primary tumor, sentinel lymph node and other nodes, wherever required. In breast cancer patients, surgery, more or less, was done on the second day of radiotracer injection. In operation theatre isosulfan blue dye and gamma probe was used to detect sentinel lymph nodes. In breast cancer patients, scintigraphy detected a total of 231 lymph nodes but failed to show sentinel lymph node in 7 patients (success rate of lymphoscintigraphy 93.1 %). Using gamma probe 158 lymph nodes were detected in 89 patients but sentinel nodes were missed in 9 patients (success rate of probe was 89.9 %). 146 lymph nodes could be visualised using blue dye in 92 patients but were missed in 12 patients (detection rate by dye was 87 %). In 2 patients sentinel lymph node could not be detected by any method. In patients with melanoma, scintigraphy showed 304 lymph nodes. However, it did not detect sentinel lymph node in 9 patients (success rate of lymphoscintigraphy was 94.6 %). 104 patients were examined by means of gamma probe and 132 lymph nodes were detected and no lymph node was found in 13 patients (success rate of probe 87.5%). Using blue dye in 140 patients, 131 nodes were found but were

  14. Effect of recall rate on earlier screen detection of breast cancers based on the Dutch performance indicators.

    NARCIS (Netherlands)

    Otten, J.D.M.; Karssemeijer, N.; Hendriks, J.H.C.L.; Groenewoud, J.H.; Fracheboud, J.; Verbeek, A.L.M.; Koning, H.J. de; Holland, R.

    2005-01-01

    BACKGROUND: The recall rate (i.e., the rate at which mammographically screened women are recalled for additional assessment) in the Dutch breast screening program (0.89% in 2000 for subsequent examinations) is the lowest worldwide, with possible consequences including higher rates of late-detected

  15. Low-Rate DDoS Attack Detection Using Expectation of Packet Size

    Directory of Open Access Journals (Sweden)

    Lu Zhou

    2017-01-01

    Full Text Available Low-rate Distributed Denial-of-Service (low-rate DDoS attacks are a new challenge to cyberspace, as the attackers send a large amount of attack packets similar to normal traffic, to throttle legitimate flows. In this paper, we propose a measurement—expectation of packet size—that is based on the distribution difference of the packet size to distinguish two typical low-rate DDoS attacks, the constant attack and the pulsing attack, from legitimate traffic. The experimental results, obtained using a series of real datasets with different times and different tolerance factors, are presented to demonstrate the effectiveness of the proposed measurement. In addition, extensive experiments are performed to show that the proposed measurement can detect the low-rate DDoS attacks not only in the short and long terms but also for low packet rates and high packet rates. Furthermore, the false-negative rates and the adjudication distance can be adjusted based on the detection sensitivity requirements.

  16. Performance Test of BF3 Neutron Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yu Sun; Shin, Ho Cheol [KHNP-CRI, Daejeon (Korea, Republic of); Cho, Jin Bok; Oh, Sae Hyun; Ryou, Seok Jean [USERS, Daejeon (Korea, Republic of)

    2015-10-15

    The neutron detecting system of First-of-a-kind plant such an APR1400 at Shin Kori should have been verified in the condition of low operating temperature and pressure of the primary coolant system before receiving the operation license. Auxiliary Ex-core Neutron Flux Monitoring System (AENFMS) is supposed to be installed using BF3 neutron detector in Shin Kori plant. The performance test of AENFMS was conducted to measure neutron sensitivity, moderation ratio and count rate in the same condition with Ex-core Neutron Flux Monitoring System (ENFMS) of APR1400 to verify its detection characteristics in compliance with the functional requirement. Performance test has been conducted for AENFMS of APR1400 to verify BF3 neutron sensitivity, moderation ration of PE, expecting neutron signal count rate from AENFMS, possible extending cable length from detector to pre-amplifier. As a result of measurement, the neutron sensitivity of 34.246±0.168(95%CI)cps/nv, moderation ratio of 11.343±0.039(95%CI) and AENFMS expecting count rate related to ENFMS of 17.8 times are acceptable in compliance with functional requirement, respectively.

  17. Continuous detection of weak sensory signals in afferent spike trains: the role of anti-correlated interspike intervals in detection performance.

    Science.gov (United States)

    Goense, J B M; Ratnam, R

    2003-10-01

    An important problem in sensory processing is deciding whether fluctuating neural activity encodes a stimulus or is due to variability in baseline activity. Neurons that subserve detection must examine incoming spike trains continuously, and quickly and reliably differentiate signals from baseline activity. Here we demonstrate that a neural integrator can perform continuous signal detection, with performance exceeding that of trial-based procedures, where spike counts in signal- and baseline windows are compared. The procedure was applied to data from electrosensory afferents of weakly electric fish (Apteronotus leptorhynchus), where weak perturbations generated by small prey add approximately 1 spike to a baseline of approximately 300 spikes s(-1). The hypothetical postsynaptic neuron, modeling an electrosensory lateral line lobe cell, could detect an added spike within 10-15 ms, achieving near ideal detection performance (80-95%) at false alarm rates of 1-2 Hz, while trial-based testing resulted in only 30-35% correct detections at that false alarm rate. The performance improvement was due to anti-correlations in the afferent spike train, which reduced both the amplitude and duration of fluctuations in postsynaptic membrane activity, and so decreased the number of false alarms. Anti-correlations can be exploited to improve detection performance only if there is memory of prior decisions.

  18. Estimating detection rates for the LIGO-Virgo search for gravitational-wave burst counterparts to gamma-ray bursts using inferred local GRB rates

    International Nuclear Information System (INIS)

    Leonor, I; Frey, R; Sutton, P J; Jones, G; Marka, S; Marka, Z

    2009-01-01

    One of the ongoing searches performed using the LIGO-Virgo network of gravitational-wave interferometers is the search for gravitational-wave burst (GWB) counterparts to gamma-ray bursts (GRBs). This type of analysis makes use of GRB time and position information from gamma-ray satellite detectors to trigger the GWB search, and the GWB detection rates possible for such an analysis thus strongly depend on the GRB detection efficiencies of the satellite detectors. Using local GRB rate densities inferred from observations which are found in the science literature, we calculate estimates of the GWB detection rates for different configurations of the LIGO-Virgo network for this type of analysis.

  19. Leak rate models and leak detection

    International Nuclear Information System (INIS)

    1992-01-01

    Leak detection may be carried out by a number of detection systems, but selection of the systems must be carefully adapted to the fluid state and the location of the leak in the reactor coolant system. Computer programs for the calculation of leak rates contain different models to take into account the fluid state before its entrance into the crack, and they have to be verified by experiments; agreement between experiments and calculations is generally not satisfactory for very small leak rates resulting from narrow cracks or from a closing bending moment

  20. QRS peak detection for heart rate monitoring on Android smartphone

    Science.gov (United States)

    Pambudi Utomo, Trio; Nuryani, Nuryani; Darmanto

    2017-11-01

    In this study, Android smartphone is used for heart rate monitoring and displaying electrocardiogram (ECG) graph. Heart rate determination is based on QRS peak detection. Two methods are studied to detect the QRS complex peak; they are Peak Threshold and Peak Filter. The acquisition of ECG data is utilized by AD8232 module from Analog Devices, three electrodes, and Microcontroller Arduino UNO R3. To record the ECG data from a patient, three electrodes are attached to particular body’s surface of a patient. Patient’s heart activity which is recorded by AD8232 module is decoded by Arduino UNO R3 into analog data. Then, the analog data is converted into a voltage value (mV) and is processed to get the QRS complex peak. Heart rate value is calculated by Microcontroller Arduino UNO R3 uses the QRS complex peak. Voltage, heart rate, and the QRS complex peak are sent to Android smartphone by Bluetooth HC-05. ECG data is displayed as the graph by Android smartphone. To evaluate the performance of QRS complex peak detection method, three parameters are used; they are positive predictive, accuracy and sensitivity. Positive predictive, accuracy, and sensitivity of Peak Threshold method is 92.39%, 70.30%, 74.62% and for Peak Filter method are 98.38%, 82.47%, 83.61%, respectively.

  1. DOUBLE COMPACT OBJECTS. III. GRAVITATIONAL-WAVE DETECTION RATES

    Energy Technology Data Exchange (ETDEWEB)

    Dominik, Michal; Belczynski, Krzysztof; Bulik, Tomasz [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw (Poland); Berti, Emanuele [Department of Physics and Astronomy, The University of Mississippi, University, MS 38677 (United States); O’Shaughnessy, Richard [Center for Gravitation, Cosmology, and Astrophysics, University of Wisconsin-Milwaukee, Milwaukee, WI (United States); Mandel, Ilya [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Fryer, Christopher [CCS-2, MSD409, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Holz, Daniel E. [Enrico Fermi Institute, Department of Physics, and Kavli Institute for Cosmological Physics University of Chicago, Chicago, IL 60637 (United States); Pannarale, Francesco [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA (United Kingdom)

    2015-06-20

    The unprecedented range of second-generation gravitational-wave (GW) observatories calls for refining the predictions of potential sources and detection rates. The coalescence of double compact objects (DCOs)—i.e., neutron star–neutron star (NS–NS), black hole–neutron star (BH–NS), and black hole–black hole (BH–BH) binary systems—is the most promising source of GWs for these detectors. We compute detection rates of coalescing DCOs in second-generation GW detectors using the latest models for their cosmological evolution, and implementing inspiral-merger-ringdown gravitational waveform models in our signal-to-noise ratio calculations. We find that (1) the inclusion of the merger/ringdown portion of the signal does not significantly affect rates for NS–NS and BH–NS systems, but it boosts rates by a factor of ∼1.5 for BH–BH systems; (2) in almost all of our models BH–BH systems yield by far the largest rates, followed by NS–NS and BH–NS systems, respectively; and (3) a majority of the detectable BH–BH systems were formed in the early universe in low-metallicity environments. We make predictions for the distributions of detected binaries and discuss what the first GW detections will teach us about the astrophysics underlying binary formation and evolution.

  2. Novel Method For Low-Rate Ddos Attack Detection

    Science.gov (United States)

    Chistokhodova, A. A.; Sidorov, I. D.

    2018-05-01

    The relevance of the work is associated with an increasing number of advanced types of DDoS attacks, in particular, low-rate HTTP-flood. Last year, the power and complexity of such attacks increased significantly. The article is devoted to the analysis of DDoS attacks detecting methods and their modifications with the purpose of increasing the accuracy of DDoS attack detection. The article details low-rate attacks features in comparison with conventional DDoS attacks. During the analysis, significant shortcomings of the available method for detecting low-rate DDoS attacks were found. Thus, the result of the study is an informal description of a new method for detecting low-rate denial-of-service attacks. The architecture of the stand for approbation of the method is developed. At the current stage of the study, it is possible to improve the efficiency of an already existing method by using a classifier with memory, as well as additional information.

  3. Rate modulation detection thresholds for cochlear implant users.

    Science.gov (United States)

    Brochier, Tim; McKay, Colette; McDermott, Hugh

    2018-02-01

    The perception of temporal amplitude modulations is critical for speech understanding by cochlear implant (CI) users. The present study compared the ability of CI users to detect sinusoidal modulations of the electrical stimulation rate and current level, at different presentation levels (80% and 40% of the dynamic range) and modulation frequencies (10 and 100 Hz). Rate modulation detection thresholds (RMDTs) and amplitude modulation detection thresholds (AMDTs) were measured and compared to assess whether there was a perceptual advantage to either modulation method. Both RMDTs and AMDTs improved with increasing presentation level and decreasing modulation frequency. RMDTs and AMDTs were correlated, indicating that a common processing mechanism may underlie the perception of rate modulation and amplitude modulation, or that some subject-dependent factors affect both types of modulation detection.

  4. Time of day variation in polyp detection rate for colonoscopies performed on a 3-hour shift schedule.

    LENUS (Irish Health Repository)

    Munson, Gregory W

    2011-03-01

    Recent research suggests that the colonoscopy polyp detection rate (PDR) varies by time of day, possibly because of endoscopist fatigue. Mayo Clinic Rochester (MCR) schedules colonoscopies on 3-hour shifts, which should minimize fatigue.

  5. Microchannel electron multiplier: improvement in gain performances and detection dynamics

    International Nuclear Information System (INIS)

    Audier, M.; Delmotte, J.C.; Boutot, J.P.

    1978-01-01

    The performances of an MCP are a function of its geometrical characteristics (diameter d and ratio 1/d of a channel, useful area) and of the applied voltage. Gain and mean output current are limited by saturation phenomena. By using a particular cascaded MCP's configuration, it is possible to simultaneously improve the gain, its associated fluctuations and the detection dynamics (detected level, counting rate). For gains 10 6 7 , the fluctuations, can be kept as low as 20% and an improvement by a factor > 10 can be obtained on the detection dynamics [fr

  6. Detection limit for rate fluctuations in inhomogeneous Poisson processes

    Science.gov (United States)

    Shintani, Toshiaki; Shinomoto, Shigeru

    2012-04-01

    Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

  7. Detection limit for rate fluctuations in inhomogeneous Poisson processes.

    Science.gov (United States)

    Shintani, Toshiaki; Shinomoto, Shigeru

    2012-04-01

    Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

  8. "Binary" and "non-binary" detection tasks: are current performance measures optimal?

    Science.gov (United States)

    Gur, David; Rockette, Howard E; Bandos, Andriy I

    2007-07-01

    We have observed that a very large fraction of responses for several detection tasks during the performance of observer studies are in the extreme ranges of lower than 11% or higher than 89% regardless of the actual presence or absence of the abnormality in question or its subjectively rated "subtleness." This observation raises questions regarding the validity and appropriateness of using multicategory rating scales for such detection tasks. Monte Carlo simulation of binary and multicategory ratings for these tasks demonstrate that the use of the former (binary) often results in a less biased and more precise summary index and hence may lead to a higher statistical power for determining differences between modalities.

  9. 5 CFR 430.308 - Rating performance.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Rating performance. 430.308 Section 430.308 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERFORMANCE MANAGEMENT Managing Senior Executive Performance § 430.308 Rating performance. (a) Initial summary rating...

  10. A burst-mode photon counting receiver with automatic channel estimation and bit rate detection

    Science.gov (United States)

    Rao, Hemonth G.; DeVoe, Catherine E.; Fletcher, Andrew S.; Gaschits, Igor D.; Hakimi, Farhad; Hamilton, Scott A.; Hardy, Nicholas D.; Ingwersen, John G.; Kaminsky, Richard D.; Moores, John D.; Scheinbart, Marvin S.; Yarnall, Timothy M.

    2016-04-01

    We demonstrate a multi-rate burst-mode photon-counting receiver for undersea communication at data rates up to 10.416 Mb/s over a 30-foot water channel. To the best of our knowledge, this is the first demonstration of burst-mode photon-counting communication. With added attenuation, the maximum link loss is 97.1 dB at λ=517 nm. In clear ocean water, this equates to link distances up to 148 meters. For λ=470 nm, the achievable link distance in clear ocean water is 450 meters. The receiver incorporates soft-decision forward error correction (FEC) based on a product code of an inner LDPC code and an outer BCH code. The FEC supports multiple code rates to achieve error-free performance. We have selected a burst-mode receiver architecture to provide robust performance with respect to unpredictable channel obstructions. The receiver is capable of on-the-fly data rate detection and adapts to changing levels of signal and background light. The receiver updates its phase alignment and channel estimates every 1.6 ms, allowing for rapid changes in water quality as well as motion between transmitter and receiver. We demonstrate on-the-fly rate detection, channel BER within 0.2 dB of theory across all data rates, and error-free performance within 1.82 dB of soft-decision capacity across all tested code rates. All signal processing is done in FPGAs and runs continuously in real time.

  11. Link Between RI-ISI and Inspection Qualification: Relationship between Defect Detection Rate and Margin of Detection

    International Nuclear Information System (INIS)

    Shepherd, Barrie; Goujon, Sophie; Whittle, John

    2007-01-01

    Quantitative risk-informed in-service inspection (RI-ISI) requires a quantitative measurement of inspection effectiveness if the risk change associated with an inspection is to be determined. Knowing the probability of detection (POD) as a function of defect depth (through wall dimension) would provide ideal information. However the main in-service inspection method for nuclear plant is ultrasonics, for which defect detection capability depends on a wide variety of parameters besides defect depth, such as defect orientation, roughness, location, shape etc. In recognition of this the European approach to inspection qualification is generally based on some combination of technical justification, and practical trials on a relatively limited number of defects. This inspection qualification process involves demonstrating that defects of concern will generate responses in excess of the specified recording level or noise, depending on the inspection. It is not currently designed to quantify the probability with which defects will be detected. The work described in this report has been performed in order to help address the problem of how the information generated during inspection qualification can be used as an input for RI-ISI. The approach adopted has been to recognise that as the defect response increases above the recording or noise level, the probability of detecting defects is likely to increase. The work therefore involved an investigation of the relationship between POD (strictly speaking defect detection rate) and margin of detection. It involved blind manual and automated ultrasonic trials on artificial defects in test plates designed to generate a range of signal responses. The detection rate for defects which provided signals at a particular level above noise or above a recording level was then measured. A relationship between defect detection rate and margin of detection has been established based on these trials. In addition to establishing a stronger link

  12. Bayesian analysis of energy and count rate data for detection of low count rate radioactive sources.

    Science.gov (United States)

    Klumpp, John; Brandl, Alexander

    2015-03-01

    A particle counting and detection system is proposed that searches for elevated count rates in multiple energy regions simultaneously. The system analyzes time-interval data (e.g., time between counts), as this was shown to be a more sensitive technique for detecting low count rate sources compared to analyzing counts per unit interval (Luo et al. 2013). Two distinct versions of the detection system are developed. The first is intended for situations in which the sample is fixed and can be measured for an unlimited amount of time. The second version is intended to detect sources that are physically moving relative to the detector, such as a truck moving past a fixed roadside detector or a waste storage facility under an airplane. In both cases, the detection system is expected to be active indefinitely; i.e., it is an online detection system. Both versions of the multi-energy detection systems are compared to their respective gross count rate detection systems in terms of Type I and Type II error rates and sensitivity.

  13. Probability of detection of clinical seizures using heart rate changes.

    Science.gov (United States)

    Osorio, Ivan; Manly, B F J

    2015-08-01

    Heart rate-based seizure detection is a viable complement or alternative to ECoG/EEG. This study investigates the role of various biological factors on the probability of clinical seizure detection using heart rate. Regression models were applied to 266 clinical seizures recorded from 72 subjects to investigate if factors such as age, gender, years with epilepsy, etiology, seizure site origin, seizure class, and data collection centers, among others, shape the probability of EKG-based seizure detection. Clinical seizure detection probability based on heart rate changes, is significantly (pprobability of detecting clinical seizures (>0.8 in the majority of subjects) using heart rate is highest for complex partial seizures, increases with a patient's years with epilepsy, is lower for females than for males and is unrelated to the side of hemisphere origin. Clinical seizure detection probability using heart rate is multi-factorially dependent and sufficiently high (>0.8) in most cases to be clinically useful. Knowledge of the role that these factors play in shaping said probability will enhance its applicability and usefulness. Heart rate is a reliable and practical signal for extra-cerebral detection of clinical seizures originating from or spreading to central autonomic network structures. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  14. A Longitudinal Study of Adenoma Detection Rate in Gastroenterology Fellowship Training.

    Science.gov (United States)

    Gianotti, Robert J; Oza, Sveta Shah; Tapper, Elliot B; Kothari, Darshan; Sheth, Sunil G

    2016-10-01

    Current guidelines suggest that a gastroenterology fellow in training needs to perform 140 colonoscopies to achieve competency. Data are limited regarding adenoma detection rate (ADR) in fellowship. To assess how fellow ADR correlates with number of colonoscopies performed. We performed a retrospective study examining consecutive colonoscopies performed by gastroenterology fellows. Fellow ADR before and after the 140 procedure benchmark was compared to colonoscopies performed by attending only with whom these fellows trained. A threshold for ideal procedure count was performed using ROC analysis. We analyzed 2021 average-risk colonoscopies performed by 10 gastroenterology fellows under the supervision of an attending physician. When fellows had performed 140 colonoscopies under attending supervision (p = 0.02). The ADR of fellows who had performed >140 colonoscopies under attending supervision was greater than that of attending-only colonoscopies (36 vs. 25 %, p 325 (male patients) and 539 (female patients) colonoscopies was determined to be ideal for achieving adequate ADR based on ROC analysis. Our data suggest that ADR increases after fellows perform >140 colonoscopies under attending supervision, and thereafter surpasses the ADR of attending-only colonoscopies. Some of the differences may be driven by detection of small adenomas. The findings of this study suggest that a higher threshold for number of colonoscopies performed under attending supervision may be needed to achieve adequate ADR during fellowship prior to independent practice.

  15. Double symbol error rates for differential detection of narrow-band FM

    Science.gov (United States)

    Simon, M. K.

    1985-01-01

    This paper evaluates the double symbol error rate (average probability of two consecutive symbol errors) in differentially detected narrow-band FM. Numerical results are presented for the special case of MSK with a Gaussian IF receive filter. It is shown that, not unlike similar results previously obtained for the single error probability of such systems, large inaccuracies in predicted performance can occur when intersymbol interference is ignored.

  16. Multi-disciplinary team for early gastric cancer diagnosis improves the detection rate of early gastric cancer.

    Science.gov (United States)

    Di, Lianjun; Wu, Huichao; Zhu, Rong; Li, Youfeng; Wu, Xinglong; Xie, Rui; Li, Hongping; Wang, Haibo; Zhang, Hua; Xiao, Hong; Chen, Hui; Zhen, Hong; Zhao, Kui; Yang, Xuefeng; Xie, Ming; Tuo, Bigung

    2017-12-06

    Gastric cancer is a frequent malignant tumor worldwide and its early detection is crucial for curing the disease and enhancing patients' survival rate. This study aimed to assess whether the multi-disciplinary team (MDT) can improve the detection rate of early gastric cancer (EGC). The detection rate of EGC at the Digestive Endoscopy Center, Affiliated Hospital, Zunyi Medical College, China between September 2013 and September 2015 was analyzed. MDT for the diagnosis of EGC in the hospital was established in September 2014. The study was divided into 2 time periods: September 1, 2013 to August 31, 2014 (period 1) and September 1, 2014 to September 1, 2015 (period 2). A total of 60,800 patients' gastroscopies were performed during the two years. 61 of these patients (0.1%) were diagnosed as EGC, accounting for 16.44% (61/371) of total patients with gastric cancer. The EGC detection rate before MDT (period 1) was 0.05% (16/29403), accounting for 9.09% (16/176) of total patients with gastric cancer during this period. In comparison, the EGC detection rate during MDT (period 2) was 0.15% (45/31397), accounting for 23% (45/195) of total patients with gastric cancer during this period (P cooperation with Department of Pathology (OR = 10.1, 95% CI 2.39-43.3, P < 0.05). MDT could improve the endoscopic detection rate of EGC.

  17. PERFORMANCE COMPARISON FOR INTRUSION DETECTION SYSTEM USING NEURAL NETWORK WITH KDD DATASET

    Directory of Open Access Journals (Sweden)

    S. Devaraju

    2014-04-01

    Full Text Available Intrusion Detection Systems are challenging task for finding the user as normal user or attack user in any organizational information systems or IT Industry. The Intrusion Detection System is an effective method to deal with the kinds of problem in networks. Different classifiers are used to detect the different kinds of attacks in networks. In this paper, the performance of intrusion detection is compared with various neural network classifiers. In the proposed research the four types of classifiers used are Feed Forward Neural Network (FFNN, Generalized Regression Neural Network (GRNN, Probabilistic Neural Network (PNN and Radial Basis Neural Network (RBNN. The performance of the full featured KDD Cup 1999 dataset is compared with that of the reduced featured KDD Cup 1999 dataset. The MATLAB software is used to train and test the dataset and the efficiency and False Alarm Rate is measured. It is proved that the reduced dataset is performing better than the full featured dataset.

  18. Heart rate detection from an electronic weighing scale

    International Nuclear Information System (INIS)

    González-Landaeta, R; Casas, O; Pallàs-Areny, R

    2008-01-01

    We propose a novel technique for beat-to-beat heart rate detection based on the ballistocardiographic (BCG) force signal from a subject standing on a common electronic weighing scale. The detection relies on sensing force variations related to the blood acceleration in the aorta, works even if wearing footwear and does not require any sensors attached to the body because it uses the load cells in the scale. We have devised an approach to estimate the sensitivity and frequency response of three commercial weighing scales to assess their capability to detect the BCG force signal. Static sensitivities ranged from 490 nV V −1 N −1 to 1670 nV V −1 N −1 . The frequency response depended on the subject's mass but it was broad enough for heart rate estimation. We have designed an electronic pulse detection system based on off-the-shelf integrated circuits to sense heart-beat-related force variations of about 0.24 N. The signal-to-noise ratio of the main peaks of the force signal detected was higher than 30 dB. A Bland–Altman plot was used to compare the RR time intervals estimated from the ECG and BCG force signals for 17 volunteers. The error was ±21 ms, which makes the proposed technique suitable for short-term monitoring of the heart rate

  19. Performance of a direct detection camera for off-axis electron holography

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Shery L.Y., E-mail: shery.chang@asu.edu [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany); LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, AZ 85287 (United States); Dwyer, Christian [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany); Department of Physics, Arizona State University, Tempe, AZ 85287 (United States); Barthel, Juri; Boothroyd, Chris B.; Dunin-Borkowski, Rafal E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2016-02-15

    The performance of a direct detection camera (DDC) is evaluated in the context of off-axis electron holographic experiments in a transmission electron microscope. Its performance is also compared directly with that of a conventional charge-coupled device (CCD) camera. The DDC evaluated here can be operated either by the detection of individual electron events (counting mode) or by the effective integration of many such events during a given exposure time (linear mode). It is demonstrated that the improved modulation transfer functions and detective quantum efficiencies of both modes of the DDC give rise to significant benefits over the conventional CCD cameras, specifically, a significant improvement in the visibility of the holographic fringes and a reduction of the statistical error in the phase of the reconstructed electron wave function. The DDC's linear mode, which can handle higher dose rates, allows optimisation of the dose rate to achieve the best phase resolution for a wide variety of experimental conditions. For suitable conditions, the counting mode can potentially utilise a significantly lower dose to achieve a phase resolution that is comparable to that achieved using the linear mode. The use of multiple holograms and correlation techniques to increase the total dose in counting mode is also demonstrated. - Highlights: • Performance of a direct detection camera for off-axis electron holography has been evaluated. • Better holographic fringe visibility and phase resolution are achieved using DDC. • Both counting and linear modes offered by DDC are advantageous for different dose regimes.

  20. Performance of a direct detection camera for off-axis electron holography

    International Nuclear Information System (INIS)

    Chang, Shery L.Y.; Dwyer, Christian; Barthel, Juri; Boothroyd, Chris B.; Dunin-Borkowski, Rafal E.

    2016-01-01

    The performance of a direct detection camera (DDC) is evaluated in the context of off-axis electron holographic experiments in a transmission electron microscope. Its performance is also compared directly with that of a conventional charge-coupled device (CCD) camera. The DDC evaluated here can be operated either by the detection of individual electron events (counting mode) or by the effective integration of many such events during a given exposure time (linear mode). It is demonstrated that the improved modulation transfer functions and detective quantum efficiencies of both modes of the DDC give rise to significant benefits over the conventional CCD cameras, specifically, a significant improvement in the visibility of the holographic fringes and a reduction of the statistical error in the phase of the reconstructed electron wave function. The DDC's linear mode, which can handle higher dose rates, allows optimisation of the dose rate to achieve the best phase resolution for a wide variety of experimental conditions. For suitable conditions, the counting mode can potentially utilise a significantly lower dose to achieve a phase resolution that is comparable to that achieved using the linear mode. The use of multiple holograms and correlation techniques to increase the total dose in counting mode is also demonstrated. - Highlights: • Performance of a direct detection camera for off-axis electron holography has been evaluated. • Better holographic fringe visibility and phase resolution are achieved using DDC. • Both counting and linear modes offered by DDC are advantageous for different dose regimes.

  1. Leak rate measurements and detection systems

    International Nuclear Information System (INIS)

    Kupperman, D.; Shack, W.J.; Claytor, T.

    1983-10-01

    A research program is under way to evaluate and develop improve leak detection systems. The primary focus of the work has been on acoustic emission detection of leaks. Leaks from artificial flaws, laboratory-generated IGSCCs and thermal fatigue cracks, and field-induced intergranular stress corrosion cracks (IGSCCs) from reactor piping have been examined. The effects of pressure, temperature, and leak rate and geometry on the acoustic signature are under study. The use of cross-correlation techniques for leak location and pattern recognition and autocorrelation for source discrimination is also being considered

  2. Opportunistic mammography screening provides effective detection rates in a limited resource healthcare system.

    Science.gov (United States)

    Teh, Yew-Ching; Tan, Gie-Hooi; Taib, Nur Aishah; Rahmat, Kartini; Westerhout, Caroline Judy; Fadzli, Farhana; See, Mee-Hoong; Jamaris, Suniza; Yip, Cheng-Har

    2015-05-15

    Breast cancer is the leading cause of cancer deaths in women world-wide. In low and middle income countries, where there are no population-based mammographic screening programmes, late presentation is common, and because of inadequate access to optimal treatment, survival rates are poor. Mammographic screening is well-studied in high-income countries in western populations, and because it has been shown to reduce breast cancer mortality, it has become part of the healthcare systems in such countries. However the performance of mammographic screening in a developing country is largely unknown. This study aims to evaluate the performance of mammographic screening in Malaysia, a middle income country, and to compare the stage and surgical treatment of screen-detected and symptomatic breast cancer. A retrospective review of 2510 mammograms performed from Jan to Dec 2010 in a tertiary medical centre is carried out. The three groups identified are the routine (opportunistic) screening group, the targeted (high risk) screening group and the diagnostic group. The performance indicators of each group is calculated, and stage at presentation and treatment between the screening and diagnostic group is analyzed. The cancer detection rate in the opportunistic screening group, targeted screening group, and the symptomatic group is 0.5 %, 1.25 % and 26 % respectively. The proportion of ductal carcinoma in situ is 23.1 % in the two screening groups compared to only 2.5 % in the diagnostic group. Among the opportunistic screening group, the cancer detection rate was 0.2 % in women below 50 years old compared to 0.65 % in women 50 years and above. The performance indicators are within international standards. Early-staged breast cancer (Stage 0-2) were 84.6 % in the screening groups compared to 61.1 % in the diagnostic group. From the results, in a setting with resource constraints, targeted screening of high risk individuals will give a higher yield, and if more resources are

  3. A broad-application microchannel-plate detector system for advanced particle or photon detection tasks large area imaging, precise multi-hit timing information and high detection rate

    CERN Document Server

    Jagutzki, O; Mergel, V; Schmidt-Böcking, H; Spielberger, L; Spillmann, U; Ullmann-Pfleger, K

    2002-01-01

    New applications for single particle and photon detection in many fields require both large area imaging performance and precise time information on each detected particle. Moreover, a very high data acquisition rate is desirable for most applications and eventually the detection and imaging of more than one particle arriving within a microsecond is required. Commercial CCD systems lack the timing information whereas other electronic microchannel plate (MCP) read-out schemes usually suffer from a low acquisition rate and complicated and sometimes costly read-out electronics. We have designed and tested a complete imaging system consisting of an MCP position readout with helical wire delay-lines, single-unit amplifier box and PC-controlled time-to-digital converter (TDC) readout. The system is very flexible and can detect and analyse position and timing information at single particle rates beyond 1 MHz. Alternatively, multi-hit events can be collected and analysed at about 20 kHz rate. We discuss the advantage...

  4. Relationship of detection rate of PET cancer screening examinees and risk factors. Analysis of background of examinees

    International Nuclear Information System (INIS)

    Shibata, Koji; Uno, Kimiichi; Arai, Masami; Matsuura, Masaaki; Yoshida, Teruhiko; Momose, Toshimitsu; Ohtomo, Kuni

    2011-01-01

    Positron emission tomography (PET) cancer screening is performed widely in Japan as opportunistic screening, but no study has focused on the correlation with various cancer risk factors and the seeking bias of examinees and cancer detection rate. Analyzing our large series of PET cancer screening data, correlations with cancer detection rates according to general cancer risk factors and PET detection survey were reviewed, and the selection bias of the medical examinees was determined. 19189 examinees who underwent PET cancer screening were enrolled. Using logistic-regression analysis, we analyzed correlations between smoking history/drinking history/cancer family history and detection rates of thyroid cancer/breast cancer/colorectal cancer/lung cancer, which are the main malignancies detected in PET cancer screening. In addition, we evaluated seeking bias of examinees, analyzing correlations between the presence of cancer risk factors and prior screening checkups at other institutions to our PET cancer screening using a matched case-control study. Cancer detection rates by FDG-PET were 1.17% (224/19189), being much higher than those of standard cancer mass screenings. In males, statistically significant correlations were seen between lung cancer and smoking, and between prostate cancer and a family history of prostate cancer, but not between the detection rates of three other types of cancer (thyroid cancer/lung cancer/colorectal cancer) and other cancer risk factors. In females, detection rates of four types of cancer (thyroid cancer/lung cancer/colorectal cancer/breast cancer) were significantly higher in the examinees without cancer risks, and subgroup analysis according to types of cancer did not indicate significant correlations either. The matched case-control study evaluating seeking bias indicated that a significant proportion of the examinees with cancer risks had undergone prior cancer screening at other institutions. Our study indicated that there was

  5. Computer-Aided Detection of Malignant Lung Nodules on Chest Radiographs: Effect on Observers' Performance

    International Nuclear Information System (INIS)

    Lee, Kyung Hee; Goo, Jin Mo; Park, Chang Min; Lee, Hyun Ju; Jin, Kwang Nam

    2012-01-01

    To evaluate the effect of computer-aided detection (CAD) system on observer performance in the detection of malignant lung nodules on chest radiograph. Two hundred chest radiographs (100 normal and 100 abnormal with malignant solitary lung nodules) were evaluated. With CT and histological confirmation serving as a reference, the mean nodule size was 15.4 mm (range, 7-20 mm). Five chest radiologists and five radiology residents independently interpreted both the original radiographs and CAD output images using the sequential testing method. The performances of the observers for the detection of malignant nodules with and without CAD were compared using the jackknife free-response receiver operating characteristic analysis. Fifty-nine nodules were detected by the CAD system with a false positive rate of 1.9 nodules per case. The detection of malignant lung nodules significantly increased from 0.90 to 0.92 for a group of observers, excluding one first-year resident (p = 0.04). When lowering the confidence score was not allowed, the average figure of merit also increased from 0.90 to 0.91 (p = 0.04) for all observers after a CAD review. On average, the sensitivities with and without CAD were 87% and 84%, respectively; the false positive rates per case with and without CAD were 0.19 and 0.17, respectively. The number of additional malignancies detected following true positive CAD marks ranged from zero to seven for the various observers. The CAD system may help improve observer performance in detecting malignant lung nodules on chest radiographs and contribute to a decrease in missed lung cancer.

  6. BIRDNEST: Bayesian Inference for Ratings-Fraud Detection

    OpenAIRE

    Hooi, Bryan; Shah, Neil; Beutel, Alex; Gunnemann, Stephan; Akoglu, Leman; Kumar, Mohit; Makhija, Disha; Faloutsos, Christos

    2015-01-01

    Review fraud is a pervasive problem in online commerce, in which fraudulent sellers write or purchase fake reviews to manipulate perception of their products and services. Fake reviews are often detected based on several signs, including 1) they occur in short bursts of time; 2) fraudulent user accounts have skewed rating distributions. However, these may both be true in any given dataset. Hence, in this paper, we propose an approach for detecting fraudulent reviews which combines these 2 app...

  7. Bayesian analysis of energy and count rate data for detection of low count rate radioactive sources

    Energy Technology Data Exchange (ETDEWEB)

    Klumpp, John [Colorado State University, Department of Environmental and Radiological Health Sciences, Molecular and Radiological Biosciences Building, Colorado State University, Fort Collins, Colorado, 80523 (United States)

    2013-07-01

    We propose a radiation detection system which generates its own discrete sampling distribution based on past measurements of background. The advantage to this approach is that it can take into account variations in background with respect to time, location, energy spectra, detector-specific characteristics (i.e. different efficiencies at different count rates and energies), etc. This would therefore be a 'machine learning' approach, in which the algorithm updates and improves its characterization of background over time. The system would have a 'learning mode,' in which it measures and analyzes background count rates, and a 'detection mode,' in which it compares measurements from an unknown source against its unique background distribution. By characterizing and accounting for variations in the background, general purpose radiation detectors can be improved with little or no increase in cost. The statistical and computational techniques to perform this kind of analysis have already been developed. The necessary signal analysis can be accomplished using existing Bayesian algorithms which account for multiple channels, multiple detectors, and multiple time intervals. Furthermore, Bayesian machine-learning techniques have already been developed which, with trivial modifications, can generate appropriate decision thresholds based on the comparison of new measurements against a nonparametric sampling distribution. (authors)

  8. Radiologists' Performance for Detecting Lesions and the Interobserver Variability of Automated Whole Breast Ultrasound

    International Nuclear Information System (INIS)

    Kim, Sung Hun; Kang, Bong Joo; Choi, Byung Gil; Choi, Jae Jung; Lee, Ji Hye; Song, Byung Joo; Choe, Byung Joo; Park, Sarah; Kim, Hyunbin

    2013-01-01

    To compare the detection performance of the automated whole breast ultrasound (AWUS) with that of the hand-held breast ultrasound (HHUS) and to evaluate the interobserver variability in the interpretation of the AWUS. AWUS was performed in 38 breast cancer patients. A total of 66 lesions were included: 38 breast cancers, 12 additional malignancies and 16 benign lesions. Three breast radiologists independently reviewed the AWUS data and analyzed the breast lesions according to the BI-RADS classification. The detection rate of malignancies was 98.0% for HHUS and 90.0%, 88.0% and 96.0% for the three readers of the AWUS. The sensitivity and the specificity were 98.0% and 62.5% in HHUS, 90.0% and 87.5% for reader 1, 88.0% and 81.3% for reader 2, and 96.0% and 93.8% for reader 3, in AWUS. There was no significant difference in the radiologists' detection performance, sensitivity and specificity (p > 0.05) between the two modalities. The interobserver agreement was fair to good for the ultrasonographic features, categorization, size, and the location of breast masses. AWUS is thought to be useful for detecting breast lesions. In comparison with HHUS, AWUS shows no significant difference in the detection rate, sensitivity and the specificity, with high degrees of interobserver agreement

  9. Radiologists' Performance for Detecting Lesions and the Interobserver Variability of Automated Whole Breast Ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Hun; Kang, Bong Joo; Choi, Byung Gil; Choi, Jae Jung; Lee, Ji Hye [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Song, Byung Joo; Choe, Byung Joo [Department of General Surgery, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Park, Sarah [Department of Internal Medicine, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Kim, Hyunbin [CMC Clinical Research Coordinating Center, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of)

    2013-07-01

    To compare the detection performance of the automated whole breast ultrasound (AWUS) with that of the hand-held breast ultrasound (HHUS) and to evaluate the interobserver variability in the interpretation of the AWUS. AWUS was performed in 38 breast cancer patients. A total of 66 lesions were included: 38 breast cancers, 12 additional malignancies and 16 benign lesions. Three breast radiologists independently reviewed the AWUS data and analyzed the breast lesions according to the BI-RADS classification. The detection rate of malignancies was 98.0% for HHUS and 90.0%, 88.0% and 96.0% for the three readers of the AWUS. The sensitivity and the specificity were 98.0% and 62.5% in HHUS, 90.0% and 87.5% for reader 1, 88.0% and 81.3% for reader 2, and 96.0% and 93.8% for reader 3, in AWUS. There was no significant difference in the radiologists' detection performance, sensitivity and specificity (p > 0.05) between the two modalities. The interobserver agreement was fair to good for the ultrasonographic features, categorization, size, and the location of breast masses. AWUS is thought to be useful for detecting breast lesions. In comparison with HHUS, AWUS shows no significant difference in the detection rate, sensitivity and the specificity, with high degrees of interobserver agreement.

  10. Performance Analysis of Ship Wake Detection on Sentinel-1 SAR Images

    Directory of Open Access Journals (Sweden)

    Maria Daniela Graziano

    2017-10-01

    Full Text Available A novel technique for ship wake detection has been recently proposed and applied on X-band Synthetic Aperture Radar images provided by COSMO/SkyMed and TerraSAR-X. The approach shows that the vast majority of wake features are correctly detected and validated in critical situations. In this paper, the algorithm was applied to 28 wakes imaged by Sentinel-1 mission with different polarizations and incidence angles with the aim of testing the method’s robustness with reference to radar frequency and resolution. The detection process is properly modified. The results show that the features were correctly classified in 78.5% of cases, whereas false confirmations occur mainly on Kelvin cusps. Finally, the results were compared with the algorithm performance on X-band images, showing that no significant difference arises. In fact, the total false confirmations rate was 15.8% on X-band images and 18.5% on C-band images. Moreover, since the main criticality concerns again the false confirmation of Kelvin cusps, the same empirical criterion suggested for the X-band SAR images yielded a negligible 1.5% of false detection rate.

  11. Topic-oriented community detection of rating-based social networks

    Directory of Open Access Journals (Sweden)

    Ali Reihanian

    2016-07-01

    Full Text Available Nowadays, real world social networks contain a vast range of information including shared objects, comments, following information, etc. Finding meaningful communities in this kind of networks is an interesting research area and has attracted the attention of many researchers. The community structure of complex networks reveals both their organization and hidden relations among their constituents. Most of the researches in the field of community detection mainly focus on the topological structure of the network without performing any content analysis. In recent years, a number of researches have proposed approaches which consider both the contents that are interchanged in networks, and the topological structures of the networks in order to find more meaningful communities. In this research, the effect of topic analysis in finding more meaningful communities in social networking sites in which the users express their feelings toward different objects (like movies by means of rating is demonstrated by performing extensive experiments.

  12. Minimum detectable gas concentration performance evaluation method for gas leak infrared imaging detection systems.

    Science.gov (United States)

    Zhang, Xu; Jin, Weiqi; Li, Jiakun; Wang, Xia; Li, Shuo

    2017-04-01

    Thermal imaging technology is an effective means of detecting hazardous gas leaks. Much attention has been paid to evaluation of the performance of gas leak infrared imaging detection systems due to several potential applications. The minimum resolvable temperature difference (MRTD) and the minimum detectable temperature difference (MDTD) are commonly used as the main indicators of thermal imaging system performance. This paper establishes a minimum detectable gas concentration (MDGC) performance evaluation model based on the definition and derivation of MDTD. We proposed the direct calculation and equivalent calculation method of MDGC based on the MDTD measurement system. We build an experimental MDGC measurement system, which indicates the MDGC model can describe the detection performance of a thermal imaging system to typical gases. The direct calculation, equivalent calculation, and direct measurement results are consistent. The MDGC and the minimum resolvable gas concentration (MRGC) model can effectively describe the performance of "detection" and "spatial detail resolution" of thermal imaging systems to gas leak, respectively, and constitute the main performance indicators of gas leak detection systems.

  13. Detection of exudates in fundus imagery using a constant false-alarm rate (CFAR) detector

    Science.gov (United States)

    Khanna, Manish; Kapoor, Elina

    2014-05-01

    Diabetic retinopathy is the leading cause of blindness in adults in the United States. The presence of exudates in fundus imagery is the early sign of diabetic retinopathy so detection of these lesions is essential in preventing further ocular damage. In this paper we present a novel technique to automatically detect exudates in fundus imagery that is robust against spatial and temporal variations of background noise. The detection threshold is adjusted dynamically, based on the local noise statics around the pixel under test in order to maintain a pre-determined, constant false alarm rate (CFAR). The CFAR detector is often used to detect bright targets in radar imagery where the background clutter can vary considerably from scene to scene and with angle to the scene. Similarly, the CFAR detector addresses the challenge of detecting exudate lesions in RGB and multispectral fundus imagery where the background clutter often exhibits variations in brightness and texture. These variations present a challenge to common, global thresholding detection algorithms and other methods. Performance of the CFAR algorithm is tested against a publicly available, annotated, diabetic retinopathy database and preliminary testing suggests that performance of the CFAR detector proves to be superior to techniques such as Otsu thresholding.

  14. Single reading with computer-aided detection performed by selected radiologists in a breast cancer screening program

    Energy Technology Data Exchange (ETDEWEB)

    Bargalló, Xavier, E-mail: xbarga@clinic.cat [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Santamaría, Gorane; Amo, Montse del; Arguis, Pedro [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Ríos, José [Biostatistics and Data Management Core Facility, IDIBAPS, (Hospital Clinic) C/ Mallorca, 183. Floor -1. Office #60. 08036 Barcelona (Spain); Grau, Jaume [Preventive Medicine and Epidemiology Unit, Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Burrel, Marta; Cores, Enrique; Velasco, Martín [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain)

    2014-11-15

    Highlights: • 1-The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD. • 2-The cancer detection rate improved at the cost of increasing recall rate. • 3-CAD, used by breast radiologists, did not help to detect more cancers. - Abstract: Objectives: To assess the impact of shifting from a standard double reading plus arbitration protocol to a single reading by experienced radiologists assisted by computer-aided detection (CAD) in a breast cancer screening program. Methods: This was a prospective study approved by the ethics committee. Data from 21,321 consecutive screening mammograms in incident rounds (2010–2012) were read following a single reading plus CAD protocol and compared with data from 47,462 consecutive screening mammograms in incident rounds (2004–2010) that were interpreted following a double reading plus arbitration protocol. For the single reading, radiologists were selected on the basis of the appraisement of their previous performance. Results: Period 2010–2012 vs. period 2004–2010: Cancer detection rate (CDR): 6.1‰ (95% confidence interval: 5.1–7.2) vs. 5.25‰; Recall rate (RR): 7.02% (95% confidence interval: 6.7–7.4) vs. 7.24% (selected readers before arbitration) and vs. 3.94 (all readers after arbitration); Predictive positive value of recall: 8.69% vs. 13.32%. Average size of invasive cancers: 14.6 ± 9.5 mm vs. 14.3 ± 9.5 mm. Stage: 0 (22.3/26.1%); I (59.2/50.8%); II (19.2/17.1%); III (3.1/3.3%); IV (0/1.9%). Specialized breast radiologists performed better than general radiologists. Conclusions: The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD, at the cost of a moderate increase of the recall rate mainly related to the lack of arbitration.

  15. A Longitudinal Examination of Rater and Ratee Effects in Performance Ratings.

    Science.gov (United States)

    Vance, Robert J.; And Others

    1983-01-01

    Investigated the consistency and loci of leniency, halo, and range restriction effects in performance ratings in a longitudinal study. Policy supervisors (N=90) rated 350 subordinates on five occasions. Concluded that reliable variance in mean ratings is partly attributable to ratees, but mainly introduced by raters. (JAC)

  16. Correction to the count-rate detection limit and sample/blank time-allocation methods

    International Nuclear Information System (INIS)

    Alvarez, Joseph L.

    2013-01-01

    A common form of count-rate detection limits contains a propagation of uncertainty error. This error originated in methods to minimize uncertainty in the subtraction of the blank counts from the gross sample counts by allocation of blank and sample counting times. Correct uncertainty propagation showed that the time allocation equations have no solution. This publication presents the correct form of count-rate detection limits. -- Highlights: •The paper demonstrated a proper method of propagating uncertainty of count rate differences. •The standard count-rate detection limits were in error. •Count-time allocation methods for minimum uncertainty were in error. •The paper presented the correct form of the count-rate detection limit. •The paper discussed the confusion between count-rate uncertainty and count uncertainty

  17. Detectability and detection rate of acute cerebral hemisphere infarcts on CT and diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Urbach, H.; Flacke, S.; Keller, E.; Textor, J.; Berlis, A.; Reul, J.; Schild, H.H.; Hartmann, A.; Solymosi, L.

    2000-01-01

    Our purpose was to compare the detectability and detection rate of acute ischaemic cerebral hemisphere infarcts on CT and diffusion-weighted MRI (DWI). We investigated 32 consecutive patients with acute hemisphere stroke with unenhanced CT and DWI within 6 h of stroke onset. The interval between CT and DWI ranged from 15 to 180 min (mean 60 min). Infarct detectability on CT and DWI was determined by comparing the initial CT, DWI and later reference images in a consensus reading of five independent examiners. The ''true'' detection rate was assessed by analysing all single readings. Two patients had intracerebral haematomas on DWI and CT and were excluded. There were 27 patients with ischaemic infarcts; all were visible on DWI and proven by follow-up. DWI was negative in three patients without a final diagnosis of infarct (100 % sensitivity, 100 % specificity, χ 2 = 30, P 2 = 1.48, P = 0.224). With regard to the single readings (30 examinations x 5 examiners = 150 readings), 63 CT readings were true positive and 72 false negative (sensitivity 47 %, specificity 86 %, χ 2 = 2.88, P = 0.089). Of the DWI readings 128 were true positive and 7 false negative (sensitivity 95 %, specificity 87 %, χ 2 = 70.67, P < 0.0001). Interobserver agreement was substantial for CT (χ= 0.72, 95 % confidence interval, 0.6-0.84) and DWI (χ= 0.82, 95 % confidence interval, 0.46-1). Taken together, detectability and detection rate of acute (< 6 h) hemisphere infarcts are significantly higher with DWI than with CT. (orig.)

  18. Predicting Performance Ratings Using Motivational Antecedents

    National Research Council Canada - National Science Library

    Zazania, Michelle

    1998-01-01

    This research examined the role of motivation in predicting peer and trainer ratings of student performance and contrasted the relative importance of various antecedents for peer and trainer ratings...

  19. Early detection of left ventricular dysfunction in asymptomatic diabetic patient using strain and strain rate echocardiographic imaging

    Directory of Open Access Journals (Sweden)

    Rania Gaber

    2014-03-01

    Conclusion: Type 2 diabetes mellitus deteriorate both LV systolic and diastolic performance. Strain and strain rate by tissue Doppler Imaging is superior to conventional Doppler in early detection and evaluation of systolic and diastolic dysfunction in type 2 diabetic patients.

  20. Detection and recurrence rate of transurethral resection of bladder tumors by narrow-band imaging: Prospective, randomized comparison with white light cystoscopy

    Directory of Open Access Journals (Sweden)

    Seung Bin Kim

    2018-03-01

    Full Text Available Purpose: The purpose of this study was to evaluate the efficacy of narrow-band imaging (NBI as a diagnostic tool for detecting bladder tumors during cystoscopy compared with white light cystoscopy (WLC. Materials and Methods: From December 2013 to June 2017, a randomized prospective study was conducted on 198 patients underwent transurethral resection of bladder tumor by a single surgeon. The patients were divided into two groups according to diagnostic method. In Group I, WLC only was performed. In Group II, NBI was additionally performed after WLC. We analyzed the rate of detection of bladder tumors as a primary endpoint. In addition, we evaluated rates of recurrence in each group. Results: There were no significant differences between the two groups in characteristics except hypertension. In the analysis of rates of detection, the probability of diagnosing cancer was 80.9% (114/141 in the WLC group, and the probability of diagnosing cancer using WLC in the NBI group was 85.5% (159/186. After switching from WLC to NBI for second-look cystoscopy in the NBI group, NBI was shown to detect additional tumors with a detection rate of 35.1% (13/37 from the perspective of the patients and 42.2% (27/64 from the perspective of the tumors. The 1-year recurrence-free rate was 72.2% in the WLC group and 85.2% in the NBI group (p=0.3. Conclusions: NBI had benefits for detecting tumors overlooked by WLC. Although the difference in the 1-year recurrence-free rate was not statistically significant, our results showed a trend for higher recurrence in the NBI group.

  1. Improved method for the determination of the cortisol production rate using high-performance liquid chromatography and liquid scintillation counting

    NARCIS (Netherlands)

    van Ingen, H. E.; Endert, E.

    1988-01-01

    Two new methods for the determination of the cortisol production rate using reversed-phase high-performance liquid chromatography are described. One uses ultraviolet detection at 205 nm, the other on-line post-column derivatization with benzamidine, followed by fluorimetric detection. The specific

  2. Cardiac arrhythmia detection using combination of heart rate variability analyses and PUCK analysis.

    Science.gov (United States)

    Mahananto, Faizal; Igasaki, Tomohiko; Murayama, Nobuki

    2013-01-01

    This paper presents cardiac arrhythmia detection using the combination of a heart rate variability (HRV) analysis and a "potential of unbalanced complex kinetics" (PUCK) analysis. Detection performance was improved by adding features extracted from the PUCK analysis. Initially, R-R interval data were extracted from the original electrocardiogram (ECG) recordings and were cut into small segments and marked as either normal or arrhythmia. HRV analyses then were conducted using the segmented R-R interval data, including a time-domain analysis, frequency-domain analysis, and nonlinear analysis. In addition to the HRV analysis, PUCK analysis, which has been implemented successfully in a foreign exchange market series to characterize change, was employed. A decision-tree algorithm was applied to all of the obtained features for classification. The proposed method was tested using the MIT-BIH arrhythmia database and had an overall classification accuracy of 91.73%. After combining features obtained from the PUCK analysis, the overall accuracy increased to 92.91%. Therefore, we suggest that the use of a PUCK analysis in conjunction with HRV analysis might improve performance accuracy for the detection of cardiac arrhythmia.

  3. A Compound Detection System Based on Ultrasonic Flow Rate and Concentration

    Directory of Open Access Journals (Sweden)

    Qing-Hui WANG

    2014-02-01

    Full Text Available This paper proposes a new detection system for monitoring gas concentration and flow rate. Velocity difference of ultrasonic wave in bi-directional propagation in measured gas is recorded and utilized for computing the online gas concentration and flow rate. Meanwhile, the temperature compensation, return signal processing and error analysis algorithms are applied to improve the accuracy. The experimental results show that, compared with the single sensor measurement of gas flow rate or concentration, the proposed detection system with lower cost and higher accuracy can be applied in the occasion which needs simultaneous monitoring of gas concentration and flow rate.

  4. Does preoperative breast MRI significantly impact on initial surgical procedure and re-operation rates in patients with screen-detected invasive lobular carcinoma?

    International Nuclear Information System (INIS)

    Sinclair, K.; Sakellariou, S.; Dawson, N.; Litherland, J.

    2016-01-01

    Aim: To investigate whether magnetic resonance imaging (MRI) changes the management of patients with screen-detected invasive lobular carcinoma (ILC). Materials and methods: A retrospective, controlled, single-centre analysis of 138 cases of screen-detected ILC was performed. All patients were assessed by a single multidisciplinary team as to whether preoperative MRI altered the initial management decision or reduced re-operation rates. Results: Forty-three percent of patients had preoperative MRI. MRI guided surgical management in 40.7% patients. Primary mastectomy rates were not significantly different between the MRI and non-MRI groups (32% and 30% respectively, p=0.71). The MRI group had a lower secondary surgery rate (6.8% versus 15.2%); however, the results did not reach statistical significance, and there were no unnecessary mastectomies. Conclusion: MRI can be used appropriately to guide primary surgery in screen-detected ILC cases and affects the initial management decision in 40.7% of patients. It does not significantly affect the overall mastectomy rate or re-operation rates, but reduces the likelihood of the latter. As a result of this review, the authors' local policy for the use of MRI in screen-detected ILC patients has been modified. For patients undergoing mastectomy for ILC, MRI is no longer performed routinely to search for contralateral malignancy as this has no proven added benefit. - Highlights: • Breast magnetic resonance imaging (MRI) allows more accurate tumour assessment and detects additional foci of disease in invasive lobular carcinoma (ILC). • Over the study's 3 year time frame, MRI guided surgical management of 40.7% screen-detected ILC patients scanned. • No statistically significant difference in mastectomy rates between MRI and non MRI groups. • Observed lower re-operation rate (6.8%-v-15.2%) in MRI group not statistically significant. • No MRI benefit for contralateral disease detection in ILC patients for

  5. Retrospective observation on contribution and limitations of screening for breast cancer with mammography in Korea: detection rate of breast cancer and incidence rate of interval cancer of the breast.

    Science.gov (United States)

    Lee, Kunsei; Kim, Hyeongsu; Lee, Jung Hyun; Jeong, Hyoseon; Shin, Soon Ae; Han, Taehwa; Seo, Young Lan; Yoo, Youngbum; Nam, Sang Eun; Park, Jong Heon; Park, Yoo Mi

    2016-11-18

    The purpose of this study was to determine the benefits and limitations of screening for breast cancer using mammography. Descriptive design with follow-up was used in the study. Data from breast cancer screening and health insurance claim data were used. The study population consisted of all participants in breast cancer screening from 2009 to 2014. Crude detection rate, positive predictive value and sensitivity and specificity of breast cancer screening and, incidence rate of interval cancer of the breast were calculated. The crude detection rate of breast cancer screening per 100,000 participants increased from 126.3 in 2009 to 182.1 in 2014. The positive predictive value of breast cancer screening per 100,000 positives increased from 741.2 in 2009 to 1,367.9 in 2014. The incidence rate of interval cancer of the breast per 100,000 negatives increased from 51.7 in 2009 to 76.3 in 2014. The sensitivities of screening for breast cancer were 74.6% in 2009 and 75.1% in 2014 and the specificities were 83.1% in 2009 and 85.7% in 2014. To increase the detection rate of breast cancer by breast cancer screening using mammography, the participation rate should be higher and an environment where accurate mammography and reading can be performed and reinforcement of quality control are required. To reduce the incidence rate of interval cancer of the breast, it will be necessary to educate women after their 20s to perform self-examination of the breast once a month regardless of participation in screening for breast cancer.

  6. PET-CT detection rate of primary breast cancer lesions. Correlation with the clinicopathological factors

    International Nuclear Information System (INIS)

    Ogawa, Tomoko; Tozaki, Mitsuhiro; Fukuma, Eisuke

    2008-01-01

    One hundred and forty lesions of primary breast cancer underwent positron emission tomography (PET)-CT between June 2006 and May 2007. The PET-CT detection rate of primary breast cancer lesions was 72.1%. The detection rate was 52.1% for invasive cancer ≤20 mm, 92.8% for invasive breast cancers >20 mm, and these results were significant. In the present study, no significant relationship was observed between tumor types, however, invasive lobular carcinoma showed a lower detection rate, 58.3%. The PET-CT results were not significantly affected by either estrogen and progesterone receptors or distant metastasis. A significant correlation regarding the detection rate of PET-CT was found with HER2 status, tumor grade, and axillary lymph node status. The detection rate was 100% for invasive cancer ≤20 mm when the interval between prior diagnostic Mammotome biopsies and PET-CT was less than 3 weeks, 18.8% for invasive cancer ≤20 mm when the interval was more than 3 weeks, and these results were significant. Mammotome biopsies may therefore affect the detection rate of PET-CT. Invasive cancers ≤20 mm showed a low detection rate, therefore, it is considered to be insufficient to use PET-CT for the detection of early breast cancer. (author)

  7. Internet addiction detection rate among college students in the People's Republic of China: a meta-analysis.

    Science.gov (United States)

    Shao, Yao-Jun; Zheng, Tong; Wang, Yan-Qiu; Liu, Ling; Chen, Yan; Yao, Ying-Shui

    2018-01-01

    With the development of economy and technology, the Internet is becoming more and more popular. Internet addiction has gradually become a serious issue in public health worldwide. The number of Internet users in China has reached 731 million, with an estimated 24 million adolescents determined as having Internet addiction. In this meta-analysis, we attempted to estimate the prevalence of Internet addiction among College Students in the People's Republic of China in order to improve the mental health level of college students and provide evidence for the prevention of Internet addiction. Eligible articles about the prevalence of Internet addiction among college students in China published between 2006 and 2017 were retrieved from online Chinese periodicals, the full-text databases of Wan Fang, VIP, and the Chinese National Knowledge Infrastructure, as well as PubMed. Stata 11.0 was used to perform the analyses. A total of 26 papers were included in the analyses. The overall sample size was 38,245, with 4573 diagnosed with Internet addiction. The pooled detection rate of Internet addiction was 11% (95% confidence interval [CI] 9-13%) among college students in China. The detection rate was higher in male students (16%) than female students (8%). The Internet addiction detection rate was 11% (95% CI 8-14%) in southern areas, 11% (95% CI 7-14%) in northern areas, 13% (95% CI 8-18%) in eastern areas and 9% (95% CI 8-11%) in the mid-western areas. According to different scales, the Internet addiction detection rate was 11% (95% CI 8-15%) using the Young scale and 9% (95% CI 6-11%) using the Chen scale respectively. Cumulative meta analysis showed that the detection rate had a slight upward trend and gradually stabilized in the last 3 years. The pooled Internet addiction detection rate of Chinese college students in out study was 11%, which is higher than in some other countries and strongly demonstrates a worrisome situation. Effective measures should be taken to prevent

  8. [Simultaneous determination of four compounds in Sanjing Shuanghuanglian Oral Liquid by high performance liquid chromatography-diode array detection-electrochemical detection].

    Science.gov (United States)

    Liu, Lin; Suo, Zhirong; Zheng, Jianbin

    2006-05-01

    Chlorogenic acid, caffeic acid, baicalin and luteolin in Sanjing Shuanghuanglian Oral Liquid were simultaneously detected and identified using a high performance liquid chromatography coupled with diode array detection and electrochemical detection (HPLC-DAD-ECD). The separation was performed on a Zorbax SB-C18 column (150 mm x 4.6 mm i. d., 5.0 microm). The mobile phase consisted of (A) methanol and (B) methanol-water-acetic acid (50: 50: 1, v/v/v) using a linear gradient elution of 2%A-3%A at 0-3 min, 3%A-25%A at 3-15 min, 25%A-80%A at 15-20 min. The flow rate was 0.8 mL/min. The DAD detection was used at 275 nm. The ECD detection was done at 0.7 V. The column thermostat set at 30 degrees C. The limits of detection of the 4 compounds were 1 mg/L for chlorogenic acid, 0.2 mg/L for caffeic acid, 9 mg/L for baicalin, 7 mg/L for luteolin. The average recoveries were between 96.6%-99.6% with relative standard deviations (RSDs) of 2.5%-4.1%. The method is simple, rapid, reproducible and accurate. It can be used for the routine analysis of the four compounds in Shuanghuanglian Oral Liquid.

  9. A Decline in Response Variability Improves Neural Signal Detection during Auditory Task Performance.

    Science.gov (United States)

    von Trapp, Gardiner; Buran, Bradley N; Sen, Kamal; Semple, Malcolm N; Sanes, Dan H

    2016-10-26

    The detection of a sensory stimulus arises from a significant change in neural activity, but a sensory neuron's response is rarely identical to successive presentations of the same stimulus. Large trial-to-trial variability would limit the central nervous system's ability to reliably detect a stimulus, presumably affecting perceptual performance. However, if response variability were to decrease while firing rate remained constant, then neural sensitivity could improve. Here, we asked whether engagement in an auditory detection task can modulate response variability, thereby increasing neural sensitivity. We recorded telemetrically from the core auditory cortex of gerbils, both while they engaged in an amplitude-modulation detection task and while they sat quietly listening to the identical stimuli. Using a signal detection theory framework, we found that neural sensitivity was improved during task performance, and this improvement was closely associated with a decrease in response variability. Moreover, units with the greatest change in response variability had absolute neural thresholds most closely aligned with simultaneously measured perceptual thresholds. Our findings suggest that the limitations imposed by response variability diminish during task performance, thereby improving the sensitivity of neural encoding and potentially leading to better perceptual sensitivity. The detection of a sensory stimulus arises from a significant change in neural activity. However, trial-to-trial variability of the neural response may limit perceptual performance. If the neural response to a stimulus is quite variable, then the response on a given trial could be confused with the pattern of neural activity generated when the stimulus is absent. Therefore, a neural mechanism that served to reduce response variability would allow for better stimulus detection. By recording from the cortex of freely moving animals engaged in an auditory detection task, we found that variability

  10. Determination of carbohydrates by high performance anion chromatography-pulsed amperometric detection in mushrooms.

    Science.gov (United States)

    Zhou, Shuai; Tang, Qingjiu; Luo, Xi; Xue, Jun-Jie; Liu, Yanfang; Yang, Yan; Zhang, Jingsong; Feng, Na

    2012-01-01

    A method of detecting carbohydrates (fucose, trehalose, mannitol, arabitol, mannose, glucose, galactose, fructose, and ribose) by high-performance anion chromatography-pulsed amperometric detection (HAPEC-PAD) was established. The conditions are: CarboPac MA1 column, NaOH as the eluent, temperature 30°C, Au working electrode, Ag/AgCl reference electrode, and flow rate 0.4 mL/min. These nine analytes, which yielded high resolution by this method, could be detected in 40 minutes. Mushrooms were tested and good precision, stability, and reproducibility were achieved. This method is suitable for mushroom samples and could support research and development on sugar and sugar alcohol, which contains special effects.

  11. Effects of platooning on signal-detection performance, workload, and stress: A driving simulator study.

    Science.gov (United States)

    Heikoop, Daniël D; de Winter, Joost C F; van Arem, Bart; Stanton, Neville A

    2017-04-01

    Platooning, whereby automated vehicles travel closely together in a group, is attractive in terms of safety and efficiency. However, concerns exist about the psychological state of the platooning driver, who is exempted from direct control, yet remains responsible for monitoring the outside environment to detect potential threats. By means of a driving simulator experiment, we investigated the effects on recorded and self-reported measures of workload and stress for three task-instruction conditions: (1) No Task, in which participants had to monitor the road, (2) Voluntary Task, in which participants could do whatever they wanted, and (3) Detection Task, in which participants had to detect red cars. Twenty-two participants performed three 40-min runs in a constant-speed platoon, one condition per run in counterbalanced order. Contrary to some classic literature suggesting that humans are poor monitors, in the Detection Task condition participants attained a high mean detection rate (94.7%) and a low mean false alarm rate (0.8%). Results of the Dundee Stress State Questionnaire indicated that automated platooning was less distressing in the Voluntary Task than in the Detection Task and No Task conditions. In terms of heart rate variability, the Voluntary Task condition yielded a lower power in the low-frequency range relative to the high-frequency range (LF/HF ratio) than the Detection Task condition. Moreover, a strong time-on-task effect was found, whereby the mean heart rate dropped from the first to the third run. In conclusion, participants are able to remain attentive for a prolonged platooning drive, and the type of monitoring task has effects on the driver's psychological state. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Computer-aided pulmonary nodule detection. Performance of two CAD systems at different CT dose levels

    International Nuclear Information System (INIS)

    Hein, Patrick Alexander; Rogalla, P.; Klessen, C.; Lembcke, A.; Romano, V.C.

    2009-01-01

    Purpose: To evaluate the impact of dose reduction on the performance of computer-aided lung nodule detection systems (CAD) of two manufacturers by comparing respective CAD results on ultra-low-dose computed tomography (ULD-CT) and standard dose CT (SD-CT). Materials and Methods: Multi-slice computed tomography (MSCT) data sets of 26 patients (13 male and 13 female, patients 31 - 74 years old) were retrospectively selected for CAD analysis. Indication for CT examination was staging of a known primary malignancy or suspected pulmonary malignancy. CT images were consecutively acquired at 5 mAs (ULD-CT) and 75 mAs (SD-CT) with 120kV tube voltage (1 mm slice thickness). The standard of reference was determined by three experienced readers in consensus. CAD reading algorithms (pre-commercial CAD system, Philips, Netherlands: CAD-1; LungCARE, Siemens, Germany: CAD-2) were applied to the CT data sets. Results: Consensus reading identified 253 nodules on SD-CT and ULD-CT. Nodules ranged in diameter between 2 and 41 mm (mean diameter 4.8 mm). Detection rates were recorded with 72% and 62% (CAD-1 vs. CAD-2) for SD-CT and with 73% and 56% for ULD-CT. Median also positive rates per patient were calculated with 6 and 5 (CAD-1 vs. CAD-2) for SD-CT and with 8 and 3 for ULD-CT. After separate statistical analysis of nodules with diameters of 5 mm and greater, the detection rates increased to 83% and 61% for SD-CT and to 89% and 67% for ULD-CT (CAD-1 vs. CAD-2). For both CAD systems there were no significant differences between the detection rates for standard and ultra-low-dose data sets (p>0.05). Conclusion: Dose reduction of the underlying CT scan did not significantly influence nodule detection performance of the tested CAD systems. (orig.)

  13. Nonlinear detection for a high rate extended binary phase shift keying system.

    Science.gov (United States)

    Chen, Xian-Qing; Wu, Le-Nan

    2013-03-28

    The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM) on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD) detector. The two detectors detect the received signals together with the special impacting filter (SIF) that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs), which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK) signal detection and can provide accurate posterior probability for LDPC decoding.

  14. Nonlinear Detection for a High Rate Extended Binary Phase Shift Keying System

    Directory of Open Access Journals (Sweden)

    Le-Nan Wu

    2013-03-01

    Full Text Available The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD detector. The two detectors detect the received signals together with the special impacting filter (SIF that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs, which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK signal detection and can provide accurate posterior probability for LDPC decoding.

  15. Simulation study on detection performance of eye-safe coherent Doppler wind lidar operating near 1.6 μm

    Science.gov (United States)

    Ma, Han; Wang, Qing; Na, Quanxin; Gao, Mingwei

    2018-01-01

    Coherent Doppler wind lidars (CDWL) are widely used in aerospace, atmospheric monitoring and other fields. The parameters of laser source such as the wavelength, pulse energy, pulse duration and pulse repetition rate (PRR) have significant influences on the detection performance of wind lidar. We established a simulation model which takes into account the effects of atmospheric transmission, backscatter, atmospheric turbulence and parameters of laser source. The maximum detection range is also calculated under the condition that the velocity estimation accuracy is 0.1 m/s by using this model. We analyzed the differences of the detection performance between two operation systems, which show the high pulse energy-low pulse repetition rate (HPE-LPRR) and low pulse energy-high repetition rate (LPE-HPRR), respectively. We proved our simulation model reliable by using the parameters of two commercial lidar products. This research has important theoretical and practical values for the design of eye-safe coherent Doppler wind lidar.

  16. Nonlinear Heart Rate Variability features for real-life stress detection. Case study: students under stress due to university examination.

    Science.gov (United States)

    Melillo, Paolo; Bracale, Marcello; Pecchia, Leandro

    2011-11-07

    This study investigates the variations of Heart Rate Variability (HRV) due to a real-life stressor and proposes a classifier based on nonlinear features of HRV for automatic stress detection. 42 students volunteered to participate to the study about HRV and stress. For each student, two recordings were performed: one during an on-going university examination, assumed as a real-life stressor, and one after holidays. Nonlinear analysis of HRV was performed by using Poincaré Plot, Approximate Entropy, Correlation dimension, Detrended Fluctuation Analysis, Recurrence Plot. For statistical comparison, we adopted the Wilcoxon Signed Rank test and for development of a classifier we adopted the Linear Discriminant Analysis (LDA). Almost all HRV features measuring heart rate complexity were significantly decreased in the stress session. LDA generated a simple classifier based on the two Poincaré Plot parameters and Approximate Entropy, which enables stress detection with a total classification accuracy, a sensitivity and a specificity rate of 90%, 86%, and 95% respectively. The results of the current study suggest that nonlinear HRV analysis using short term ECG recording could be effective in automatically detecting real-life stress condition, such as a university examination.

  17. Adenoma detection rate varies greatly during colonoscopy training

    NARCIS (Netherlands)

    van Doorn, Sascha C.; Klanderman, Robert B.; Hazewinkel, Yark; Fockens, Paul; Dekker, Evelien

    2015-01-01

    The adenoma detection rate (ADR) is considered the most important quality indicator for colonoscopy and varies widely among colonoscopists. It is unknown whether the ADR of gastroenterology consultants can already be predicted during their colonoscopy training. To evaluate the ADR of fellows in

  18. Error-rate performance analysis of opportunistic regenerative relaying

    KAUST Repository

    Tourki, Kamel

    2011-09-01

    In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path can be considered unusable, and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We first derive the exact statistics of each hop, in terms of probability density function (PDF). Then, the PDFs are used to determine accurate closed form expressions for end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation where the detector may use maximum ration combining (MRC) or selection combining (SC). Finally, we validate our analysis by showing that performance simulation results coincide with our analytical results over linear network (LN) architecture and considering Rayleigh fading channels. © 2011 IEEE.

  19. A method to test the reproducibility and to improve performance of computer-aided detection schemes for digitized mammograms

    International Nuclear Information System (INIS)

    Zheng Bin; Gur, David; Good, Walter F.; Hardesty, Lara A.

    2004-01-01

    The purpose of this study is to develop a new method for assessment of the reproducibility of computer-aided detection (CAD) schemes for digitized mammograms and to evaluate the possibility of using the implemented approach for improving CAD performance. Two thousand digitized mammograms (representing 500 cases) with 300 depicted verified masses were selected in the study. Series of images were generated for each digitized image by resampling after a series of slight image rotations. A CAD scheme developed in our laboratory was applied to all images to detect suspicious mass regions. We evaluated the reproducibility of the scheme using the detection sensitivity and false-positive rates for the original and resampled images. We also explored the possibility of improving CAD performance using three methods of combining results from the original and resampled images, including simple grouping, averaging output scores, and averaging output scores after grouping. The CAD scheme generated a detection score (from 0 to 1) for each identified suspicious region. A region with a detection score >0.5 was considered as positive. The CAD scheme detected 238 masses (79.3% case-based sensitivity) and identified 1093 false-positive regions (average 0.55 per image) in the original image dataset. In eleven repeated tests using original and ten sets of rotated and resampled images, the scheme detected a maximum of 271 masses and identified as many as 2359 false-positive regions. Two hundred and eighteen masses (80.4%) and 618 false-positive regions (26.2%) were detected in all 11 sets of images. Combining detection results improved reproducibility and the overall CAD performance. In the range of an average false-positive detection rate between 0.5 and 1 per image, the sensitivity of the scheme could be increased approximately 5% after averaging the scores of the regions detected in at least four images. At low false-positive rate (e.g., ≤average 0.3 per image), the grouping method

  20. 5 CFR 9901.412 - Rating and rewarding performance.

    Science.gov (United States)

    2010-01-01

    ...'s performance with respect to his or her performance expectations, as amplified through work... rating of record. (f) A Pay Pool Panel will — (1) Review recommended ratings of record, share assignments... consistency across the pay pool; and (2) Afford the rating official the opportunity to provide further...

  1. Measurement of the modification and interference rate of urinary albumin detected by size-exclusion HPLC

    International Nuclear Information System (INIS)

    Markó, Lajos; Molnár, Gergő Attila; Wagner, Zoltán; Szijártó, István; Mérei, Ákos; Wittmann, István; Böddi, Katalin; Szabó, Zoltán; Matus, Zoltán; Kőszegi, Tamás; Nagy, Géza

    2009-01-01

    The measurement of the excretion of urinary albumin (albuminuria) is an important and well-established method to assess clinical outcomes. A high-performance liquid chromatography (HPLC) method has been introduced to measure albuminuria. Using this method, it was found that commonly used immunological methods do not measure a fraction of urinary albumin. Some authors presumed that the reason of immuno-unreactivity is the modification of urinary albumin; some others presumed that the difference is merely because of interference. In order to decide this question, we established an HPLC method equipped with tandem UV and fluorescent detection to assess the changes in the detectability of albumin with the rate of modification. For this measurement, differently modified forms of albumin were used. Urine samples of diabetic patients were also measured to find a potential connection between the modification rate and clinical parameters. Secondly, we have established a reversed phase HPLC method to assess the interference rate. We conclude that albumin modification does not affect immunoreactivity. The modification rate of urinary albumin in diabetic patients showed a correlation with renal function. The interference rate of the albumin peak was found to be 12.7% on average, which does not explain the difference between the two methods

  2. Interference of detection rate of lumbar disc herniation by socioeconomic status.

    Science.gov (United States)

    Ji, Gyu Yeul; Oh, Chang Hyun; Jung, Nak-Yong; An, Seong Dae; Choi, Won-Seok; Kim, Jung Hoon

    2013-03-01

    Retrospective study. The objective of the study is to evaluate the relationship between the detection rate of lumbar disc herniation and socioeconomic status. Income is one important determinant of public health. Yet, there are no reports about the relationship between socioeconomic status and the detective rate of disc herniation. In this study, 443 cases were checked for lumbar computed tomography for lumbar disc herniation, and they reviewed questionnaires about their socioeconomic status, the presence of back pain or radiating pain and the presence of a medical certificate (to check the medical or surgical treatment for the pain) during the Korean conscription. Without the consideration for the presence of a medical certificate, there was no difference in spinal physical grade according to socioeconomic status (p=0.290). But, with the consideration of the presence of a medical certificate, the significant statistical differences were observed according to socioeconomic status in 249 cases in the presence of a medical certificate (p=0.028). There was a lower detection rate in low economic status individuals than those in the high economic class. The common reason for not submitting a medical certificate is that it is neither necessary for the people of lower socioeconomic status nor is it financially affordable. The prevalence of lumbar disc herniation is not different according to socioeconomic status, but the detective rate was affected by socioeconomic status. Socioeconomic status is an important factor for detecting lumbar disc herniation.

  3. Fault Detection Using the Zero Crossing Rate | Osuagwu | Nigerian ...

    African Journals Online (AJOL)

    A method of fault detection based on the zero crossing rate of the signal, Z1, and the zero crossing rate of the first order difference signal. Z2, is presented. It is shown that the parameter pair (Z1, Z2) possesses adequate discriminating potential to classify a signature as good or defective. The parameter pair also carries ...

  4. Non-contact acquisition of respiration and heart rates using Doppler radar with time domain peak-detection algorithm.

    Science.gov (United States)

    Xiaofeng Yang; Guanghao Sun; Ishibashi, Koichiro

    2017-07-01

    The non-contact measurement of the respiration rate (RR) and heart rate (HR) using a Doppler radar has attracted more attention in the field of home healthcare monitoring, due to the extremely low burden on patients, unconsciousness and unconstraint. Most of the previous studies have performed the frequency-domain analysis of radar signals to detect the respiration and heartbeat frequency. However, these procedures required long period time (approximately 30 s) windows to obtain a high-resolution spectrum. In this study, we propose a time-domain peak detection algorithm for the fast acquisition of the RR and HR within a breathing cycle (approximately 5 s), including inhalation and exhalation. Signal pre-processing using an analog band-pass filter (BPF) that extracts respiration and heartbeat signals was performed. Thereafter, the HR and RR were calculated using a peak position detection method, which was carried out via LABVIEW. To evaluate the measurement accuracy, we measured the HR and RR of seven subjects in the laboratory. As a reference of HR and RR, the persons wore contact sensors i.e., an electrocardiograph (ECG) and a respiration band. The time domain peak-detection algorithm, based on the Doppler radar, exhibited a significant correlation coefficient of HR of 0.92 and a correlation coefficient of RR of 0.99, between the ECG and respiration band, respectively.

  5. Detection rate of prostate cancer using prostate specific antigen in patients presenting with lower urinary tract symptoms: A retrospective study

    Directory of Open Access Journals (Sweden)

    Chavan P

    2009-01-01

    Full Text Available Background: Need for undertaking prostate biopsies for detection of prostate cancer is often decided on the basis of serum levels of prostate specific antigen (PSA. Aim: To evaluate the case detection rate of prostate cancer among patients presenting with lower urinary tract symptoms (LUTS on the basis of PSA levels and to assess the scope of prostate biopsy in these patients. Setting and Design: A retrospective study from a tertiary care center. Materials and Methods: The clinical and histopathological data of 922 patients presenting with LUTS in the last five years was obtained from the medical record section. They had been screened for prostate cancer using PSA and /or digital rectal examination examination followed by confirmation with prostate biopsy. Statistical Analysis Used: Detection rate and receiver operating characteristic curve were performed using SPSS 16 and Medcalc softwares. Results: The detection rate of prostate cancer according to the PSA levels was 0.6%, 2.3%, 2.5%, 34.1% and 54.9% in the PSA range of 0-4, 4-10, 10-20, 20-50 and> 50 ng/ml, respectively. Maximum prostate cancer cases were detected beyond a PSA value of 20 ng/ml whereas no significant difference in the detection rate was observed in the PSA range of 0-4, 4-10 and 10-20 ng/ml. Conclusion: A low detection rate of prostate cancer observed in the PSA range of 4-20 ng/ml in LUTS patients indicates the need for use of higher cutoff values of PSA in such cases. Therefore we recommend a cutoff of 20 ng/ml of PSA for evaluation of detection rate of prostate cancer among patients presenting with LUTS.

  6. Persistent Ratee Contaminants in Performance Appraisal.

    Science.gov (United States)

    Van Fleet, David D.; Chamberlain, Howard

    The hypothesis that conventional approaches to evaluating contaminants in performance appraisal overlook important individual ratee effects was examined. A rating form was developed that consisted of the following dimensions and behaviors: warmth; guided discourse or indirect teaching methods; control of subject matter; enthusiasm and reinforcing;…

  7. Performance Analysis of OCDMA Based on AND Detection in FTTH Access Network Using PIN & APD Photodiodes

    Science.gov (United States)

    Aldouri, Muthana; Aljunid, S. A.; Ahmad, R. Badlishah; Fadhil, Hilal A.

    2011-06-01

    In order to comprise between PIN photo detector and avalanche photodiodes in a system used double weight (DW) code to be a performance of the optical spectrum CDMA in FTTH network with point-to-multi-point (P2MP) application. The performance of PIN against APD is compared through simulation by using opt system software version 7. In this paper we used two networks designed as follows one used PIN photo detector and the second using APD photo diode, both two system using with and without erbium doped fiber amplifier (EDFA). It is found that APD photo diode in this system is better than PIN photo detector for all simulation results. The conversion used a Mach-Zehnder interferometer (MZI) wavelength converter. Also we are study, the proposing a detection scheme known as AND subtraction detection technique implemented with fiber Bragg Grating (FBG) act as encoder and decoder. This FBG is used to encode and decode the spectral amplitude coding namely double weight (DW) code in Optical Code Division Multiple Access (OCDMA). The performances are characterized through bit error rate (BER) and bit rate (BR) also the received power at various bit rate.

  8. Biometric Quantization through Detection Rate Optimized Bit Allocation

    Directory of Open Access Journals (Sweden)

    C. Chen

    2009-01-01

    Full Text Available Extracting binary strings from real-valued biometric templates is a fundamental step in many biometric template protection systems, such as fuzzy commitment, fuzzy extractor, secure sketch, and helper data systems. Previous work has been focusing on the design of optimal quantization and coding for each single feature component, yet the binary string—concatenation of all coded feature components—is not optimal. In this paper, we present a detection rate optimized bit allocation (DROBA principle, which assigns more bits to discriminative features and fewer bits to nondiscriminative features. We further propose a dynamic programming (DP approach and a greedy search (GS approach to achieve DROBA. Experiments of DROBA on the FVC2000 fingerprint database and the FRGC face database show good performances. As a universal method, DROBA is applicable to arbitrary biometric modalities, such as fingerprint texture, iris, signature, and face. DROBA will bring significant benefits not only to the template protection systems but also to the systems with fast matching requirements or constrained storage capability.

  9. [Detection rates of overweight and obesity in children and adolescents with different ethnicities in Xinjiang Uigur areas].

    Science.gov (United States)

    Li, Haixia; Li, Xiaomei; Tao, Jing; Ma, Yitong; Yang, Yining; Liu, Fen; Chen, Bangdang; Xie, Xiang; Yang, Hong

    2014-01-01

    To investigate the detection rates of overweight and obesity among Han,Uygur and Kazakh Children and adolescents in Xinjiang. Random samples were used to analyze the detection rates on overweight and obesity based on data from Han,Uygur and Kazakh Children and adolescents aged 7-14 years from 3 regions-Hetian, Kashi and Fuhai prefectures in Xinjiang Uygur Autonomous Region. Anthropometric data including weight and height was collected. Overweight and obesity were defined according to body mass index [BMI, weight (kg)/height (m²)] cutoffs recommended by the Chinese Working Group on Obesity for Children (WGOC)aged 7-14 years. The present study was performed in 11 894 Han, Uygur and Kazakh Children and adolescents aged 7-14 years. The overall prevalence rates of overweight and obesity were 5.6% and 2.9% respectively, which the difference between male and female was significant (χ² = 39.765, P overweight and obesity rate showed differences, with detection rate of overweight among Kazakh students was 12.0% , higher than the other ethnic groups. The obesity detection rate was 7.2% among Han students, which was the highest of the three ethnic groups, with differences statistically significant(χ² = 363.885, P overweight and obesity decreased with increasing age in various ethnic groups, showing a clear downward trend, with the peak at 7-9 year-olds and the difference was statistically significant(χ² = 101.479, P overweight and obesity among children and adolescents were significantly lower in Xinjiang Uygur Autonomous Region than the national average level, with differences also seen in different ethnic, gender and age groups.

  10. Error-rate performance analysis of incremental decode-and-forward opportunistic relaying

    KAUST Repository

    Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim

    2011-01-01

    In this paper, we investigate an incremental opportunistic relaying scheme where the selected relay chooses to cooperate only if the source-destination channel is of an unacceptable quality. In our study, we consider regenerative relaying in which the decision to cooperate is based on a signal-to-noise ratio (SNR) threshold and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We derive a closed-form expression for the end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact probability density function (PDF) of each hop. Furthermore, we evaluate the asymptotic error performance and the diversity order is deduced. We show that performance simulation results coincide with our analytical results. © 2011 IEEE.

  11. Error-rate performance analysis of incremental decode-and-forward opportunistic relaying

    KAUST Repository

    Tourki, Kamel

    2010-10-01

    In this paper, we investigate an incremental opportunistic relaying scheme where the selected relay chooses to cooperate only if the source-destination channel is of an unacceptable quality. In our study, we consider regenerative relaying in which the decision to cooperate is based on a signal-to-noise ratio (SNR) threshold and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We derive a closed-form expression for the end-to-end biterror rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact probability density function (PDF) of each hop. Furthermore, we evaluate the asymptotic error performance and the diversity order is deduced. We show that performance simulation results coincide with our analytical results. ©2010 IEEE.

  12. Error-rate performance analysis of incremental decode-and-forward opportunistic relaying

    KAUST Repository

    Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim

    2010-01-01

    In this paper, we investigate an incremental opportunistic relaying scheme where the selected relay chooses to cooperate only if the source-destination channel is of an unacceptable quality. In our study, we consider regenerative relaying in which the decision to cooperate is based on a signal-to-noise ratio (SNR) threshold and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We derive a closed-form expression for the end-to-end biterror rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact probability density function (PDF) of each hop. Furthermore, we evaluate the asymptotic error performance and the diversity order is deduced. We show that performance simulation results coincide with our analytical results. ©2010 IEEE.

  13. Error-rate performance analysis of incremental decode-and-forward opportunistic relaying

    KAUST Repository

    Tourki, Kamel

    2011-06-01

    In this paper, we investigate an incremental opportunistic relaying scheme where the selected relay chooses to cooperate only if the source-destination channel is of an unacceptable quality. In our study, we consider regenerative relaying in which the decision to cooperate is based on a signal-to-noise ratio (SNR) threshold and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We derive a closed-form expression for the end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact probability density function (PDF) of each hop. Furthermore, we evaluate the asymptotic error performance and the diversity order is deduced. We show that performance simulation results coincide with our analytical results. © 2011 IEEE.

  14. Dependency of human target detection performance on clutter and quality of supporting image analysis algorithms in a video surveillance task

    Science.gov (United States)

    Huber, Samuel; Dunau, Patrick; Wellig, Peter; Stein, Karin

    2017-10-01

    Background: In target detection, the success rates depend strongly on human observer performances. Two prior studies tested the contributions of target detection algorithms and prior training sessions. The aim of this Swiss-German cooperation study was to evaluate the dependency of human observer performance on the quality of supporting image analysis algorithms. Methods: The participants were presented 15 different video sequences. Their task was to detect all targets in the shortest possible time. Each video sequence showed a heavily cluttered simulated public area from a different viewing angle. In each video sequence, the number of avatars in the area was altered to 100, 150 and 200 subjects. The number of targets appearing was kept at 10%. The number of marked targets varied from 0, 5, 10, 20 up to 40 marked subjects while keeping the positive predictive value of the detection algorithm at 20%. During the task, workload level was assessed by applying an acoustic secondary task. Detection rates and detection times for the targets were analyzed using inferential statistics. Results: The study found Target Detection Time to increase and Target Detection Rates to decrease with increasing numbers of avatars. The same is true for the Secondary Task Reaction Time while there was no effect on Secondary Task Hit Rate. Furthermore, we found a trend for a u-shaped correlation between the numbers of markings and RTST indicating increased workload. Conclusion: The trial results may indicate useful criteria for the design of training and support of observers in observational tasks.

  15. Laser radar range and detection performance for MEMS corner cube retroreflector arrays

    Science.gov (United States)

    Grasso, Robert J.; Odhner, Jefferson E.; Stewart, Hamilton; McDaniel, Robert V.

    2004-12-01

    BAE SYSTEMS reports on a program to characterize the performance of MEMS corner cube retroreflector arrays under laser illumination. These arrays have significant military and commercial application in the areas of: 1) target identification; 2) target tracking; 3) target location; 4) identification friend-or-foe (IFF); 5) parcel tracking, and; 6) search and rescue assistance. BAE SYSTEMS has theoretically determined the feasibility of these devices to learn if sufficient signal-to-noise performance exists to permit a cooperative laser radar sensor to be considered for device location and interrogation. Results indicate that modest power-apertures are required to achieve SNR performance consistent with high probability of detection and low false alarm rates.

  16. Comparison of 3 Types of Readmission Rates for Measuring Hospital and Surgeon Performance After Primary Total Hip and Knee Arthroplasty.

    Science.gov (United States)

    Bottle, Alex; Loeffler, Mark D; Aylin, Paul; Ali, Adam M

    2018-02-26

    All-cause 30-day hospital readmission is in widespread use for monitoring and incentivizing hospital performance for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, little is known on the extent to which all-cause readmission is influenced by hospital or surgeon performance and whether alternative measures may be more valid. This is an observational study using multilevel modeling on English administrative data to determine the interhospital and intersurgeon variation for 3 readmission metrics: all-cause, surgical, and return-to-theater. Power calculations estimated the likelihood of identifying whether the readmission rate for a surgeon or hospital differed from the national average by a factor of 1.25, 1.5, 2, or 3 times, for both average and high-volume providers. 259,980 THAs and 311,033 TKAs were analyzed. Variations by both surgeons and hospitals were smaller for the all-cause measure than for the surgical or return-to-theater metrics, although statistical power to detect differences was higher. Statistical power to detect surgeon-level rates of 1.25 or 1.5 times the average was consistently low. However, at the hospital level, the surgical readmission measure showed more variation by hospital while maintaining excellent power to detect differences in rates between hospitals performing the average number of THA or TKA cases per year in England. In practice, more outliers than expected from purely random variation were found for all-cause and surgical readmissions, especially at hospital level. The 30-day surgical readmission rate should be considered as an adjunctive measure to 30-day all-cause readmission rate when assessing hospital performance. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Direct inference of SNP heterozygosity rates and resolution of LOH detection.

    Directory of Open Access Journals (Sweden)

    Xiaohong Li

    2007-11-01

    Full Text Available Single nucleotide polymorphisms (SNPs have been increasingly utilized to investigate somatic genetic abnormalities in premalignancy and cancer. LOH is a common alteration observed during cancer development, and SNP assays have been used to identify LOH at specific chromosomal regions. The design of such studies requires consideration of the resolution for detecting LOH throughout the genome and identification of the number and location of SNPs required to detect genetic alterations in specific genomic regions. Our study evaluated SNP distribution patterns and used probability models, Monte Carlo simulation, and real human subject genotype data to investigate the relationships between the number of SNPs, SNP HET rates, and the sensitivity (resolution for detecting LOH. We report that variances of SNP heterozygosity rate in dbSNP are high for a large proportion of SNPs. Two statistical methods proposed for directly inferring SNP heterozygosity rates require much smaller sample sizes (intermediate sizes and are feasible for practical use in SNP selection or verification. Using HapMap data, we showed that a region of LOH greater than 200 kb can be reliably detected, with losses smaller than 50 kb having a substantially lower detection probability when using all SNPs currently in the HapMap database. Higher densities of SNPs may exist in certain local chromosomal regions that provide some opportunities for reliably detecting LOH of segment sizes smaller than 50 kb. These results suggest that the interpretation of the results from genome-wide scans for LOH using commercial arrays need to consider the relationships among inter-SNP distance, detection probability, and sample size for a specific study. New experimental designs for LOH studies would also benefit from considering the power of detection and sample sizes required to accomplish the proposed aims.

  18. Detection rate of serrated polyps and serrated polyposis syndrome in colorectal cancer screening cohorts: a European overview.

    Science.gov (United States)

    IJspeert, J E G; Bevan, R; Senore, C; Kaminski, M F; Kuipers, E J; Mroz, A; Bessa, X; Cassoni, P; Hassan, C; Repici, A; Balaguer, F; Rees, C J; Dekker, E

    2017-07-01

    The role of serrated polyps (SPs) as colorectal cancer precursor is increasingly recognised. However, the true prevalence SPs is largely unknown. We aimed to evaluate the detection rate of SPs subtypes as well as serrated polyposis syndrome (SPS) among European screening cohorts. Prospectively collected screening cohorts of ≥1000 individuals were eligible for inclusion. Colonoscopies performed before 2009 and/or in individuals aged below 50 were excluded. Rate of SPs was assessed, categorised for histology, location and size. Age-sex-standardised number needed to screen (NNS) to detect SPs were calculated. Rate of SPS was assessed in cohorts with known colonoscopy follow-up data. Clinically relevant SPs (regarded as a separate entity) were defined as SPs ≥10 mm and/or SPs >5 mm in the proximal colon. Three faecal occult blood test (FOBT) screening cohorts and two primary colonoscopy screening cohorts (range 1.426-205.949 individuals) were included. Rate of SPs ranged between 15.1% and 27.2% (median 19.5%), of sessile serrated polyps between 2.2% and 4.8% (median 3.3%) and of clinically relevant SPs between 2.1% and 7.8% (median 4.6%). Rate of SPs was similar in FOBT-based cohorts as in colonoscopy screening cohorts. No apparent association between the rate of SP and gender or age was shown. Rate of SPS ranged from 0% to 0.5%, which increased to 0.4% to 0.8% after follow-up colonoscopy. The detection rate of SPs is variable among screening cohorts, and standards for reporting, detection and histopathological assessment should be established. The median rate, as found in this study, may contribute to define uniform minimum standards for males and females between 50 and 75 years of age. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. Performance limits of ICA-based heart rate identification techniques in imaging photoplethysmography

    International Nuclear Information System (INIS)

    Mannapperuma, Kavan; Holton, Benjamin D; Lesniewski, Peter J; Thomas, John C

    2015-01-01

    Imaging photoplethysmography is a relatively new technique for extracting biometric information from video images of faces. This is useful in non-invasive monitoring of patients including neonates or the aged, with respect to sudden infant death syndrome, sleep apnoea, pulmonary disease, physical or mental stress and other cardio-vascular conditions. In this paper, we investigate the limits of detection of the heart rate (HR) while reducing the video quality. We compare the performance of three independent component analysis (ICA) methods (JADE, FastICA, RADICAL), autocorrelation with signal conditioning techniques and identify the most robust approach. We discuss sources of increasing error and other limiting conditions in three situations of reduced signal-to-noise ratio: one where the area of the analyzed face is decreased from 100 to 5%, another where the face area is progressively re-sampled down to a single RGB pixel and one where the HR signal is severely reduced with respect to the boundary noise. In most cases, the cardiac pulse rate can be reliably and accurately detected from videos containing only 5% facial area or from a face occupying just 4 pixels or containing only 5% of the facial HR modulation. (paper)

  20. How Well Can We Detect Lineage-Specific Diversification-Rate Shifts? A Simulation Study of Sequential AIC Methods.

    Science.gov (United States)

    May, Michael R; Moore, Brian R

    2016-11-01

    Evolutionary biologists have long been fascinated by the extreme differences in species numbers across branches of the Tree of Life. This has motivated the development of statistical methods for detecting shifts in the rate of lineage diversification across the branches of phylogenic trees. One of the most frequently used methods, MEDUSA, explores a set of diversification-rate models, where each model assigns branches of the phylogeny to a set of diversification-rate categories. Each model is first fit to the data, and the Akaike information criterion (AIC) is then used to identify the optimal diversification model. Surprisingly, the statistical behavior of this popular method is uncharacterized, which is a concern in light of: (1) the poor performance of the AIC as a means of choosing among models in other phylogenetic contexts; (2) the ad hoc algorithm used to visit diversification models, and; (3) errors that we reveal in the likelihood function used to fit diversification models to the phylogenetic data. Here, we perform an extensive simulation study demonstrating that MEDUSA (1) has a high false-discovery rate (on average, spurious diversification-rate shifts are identified [Formula: see text] of the time), and (2) provides biased estimates of diversification-rate parameters. Understanding the statistical behavior of MEDUSA is critical both to empirical researchers-in order to clarify whether these methods can make reliable inferences from empirical datasets-and to theoretical biologists-in order to clarify the specific problems that need to be solved in order to develop more reliable approaches for detecting shifts in the rate of lineage diversification. [Akaike information criterion; extinction; lineage-specific diversification rates; phylogenetic model selection; speciation.]. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists.

  1. PERFORMANCE TREND” AND “PERFORMANCE CURRENT” RATINGS BY ECONOMIC VALUE ADDED (EVA

    Directory of Open Access Journals (Sweden)

    ALEXANDRU BOGEANU

    2013-08-01

    Full Text Available The Economic Value Added (EVA is an index of “durable development.” It was proposed by the Stern-Stewart Office and represents the true economic profit of companies. A company reports economic profit only if thereported accounting profit is higher than the opportunity cost of equity. The authors of the EVA model (Stern-Stewart have also proposed the ways of restating the financial statements to get a “fair image” of the results, thuseliminating the “accounting distortions.”Based on the performance indexes calculated based on EVA and second-generation indexes relating toEVA, we calculated two types of rating: Rating Performance Current and Rating Performance Trend. The rating iscalculated by means of the percentiles technique and the results are split into 22 rating classes.The used database is Russell 3000.

  2. Is breast compression associated with breast cancer detection and other early performance measures in a population-based breast cancer screening program?

    Science.gov (United States)

    Moshina, Nataliia; Sebuødegård, Sofie; Hofvind, Solveig

    2017-06-01

    We aimed to investigate early performance measures in a population-based breast cancer screening program stratified by compression force and pressure at the time of mammographic screening examination. Early performance measures included recall rate, rates of screen-detected and interval breast cancers, positive predictive value of recall (PPV), sensitivity, specificity, and histopathologic characteristics of screen-detected and interval breast cancers. Information on 261,641 mammographic examinations from 93,444 subsequently screened women was used for analyses. The study period was 2007-2015. Compression force and pressure were categorized using tertiles as low, medium, or high. χ 2 test, t tests, and test for trend were used to examine differences between early performance measures across categories of compression force and pressure. We applied generalized estimating equations to identify the odds ratios (OR) of screen-detected or interval breast cancer associated with compression force and pressure, adjusting for fibroglandular and/or breast volume and age. The recall rate decreased, while PPV and specificity increased with increasing compression force (p for trend screen-detected cancer, PPV, sensitivity, and specificity decreased with increasing compression pressure (p for trend breast cancer compared with low compression pressure (1.89; 95% CI 1.43-2.48). High compression force and low compression pressure were associated with more favorable early performance measures in the screening program.

  3. Microcystin Detection Characteristics of Fluorescence Immunochromatography and High Performance Liquid Chromatography

    International Nuclear Information System (INIS)

    Pyo, Dong Jin; Park, Geun Young; Choi, Jong Chon; Oh, Chang Suk

    2005-01-01

    Different detection characteristics of fluorescence immunochromatography method and high performance liquid chromatography (HPLC) method for the analysis of cyanobacterial toxins were studied. In particular, low and high limits of detection, detection time and reproducibility and detectable microcystin species were compared when fluorescence immunochromatography method and high performance liquid chromatography method were applied for the detection of microcystin (MC), a cyclic peptide toxin of the freshwater cyanobacterium Microcystis aeruginosa. A Fluorescence immunochromatography assay system has the unique advantages of short detection time and low detection limit, and high performance liquid chromatography detection method has the strong advantage of individual quantifications of several species of microcystins

  4. Consistency across repeated eyewitness interviews: contrasting police detectives' beliefs with actual eyewitness performance.

    Science.gov (United States)

    Krix, Alana C; Sauerland, Melanie; Lorei, Clemens; Rispens, Imke

    2015-01-01

    In the legal system, inconsistencies in eyewitness accounts are often used to discredit witnesses' credibility. This is at odds with research findings showing that witnesses frequently report reminiscent details (details previously unrecalled) at an accuracy rate that is nearly as high as for consistently recalled information. The present study sought to put the validity of beliefs about recall consistency to a test by directly comparing them with actual memory performance in two recall attempts. All participants watched a film of a staged theft. Subsequently, the memory group (N = 84) provided one statement immediately after the film (either with the Self-Administered Interview or free recall) and one after a one-week delay. The estimation group (N = 81) consisting of experienced police detectives estimated the recall performance of the memory group. The results showed that actual recall performance was consistently underestimated. Also, a sharp decline of memory performance between recall attempts was assumed by the estimation group whereas actual accuracy remained stable. While reminiscent details were almost as accurate as consistent details, they were estimated to be much less accurate than consistent information and as inaccurate as direct contradictions. The police detectives expressed a great concern that reminiscence was the result of suggestive external influences. In conclusion, it seems that experienced police detectives hold many implicit beliefs about recall consistency that do not correspond with actual recall performance. Recommendations for police trainings are provided. These aim at fostering a differentiated view on eyewitness performance and the inclusion of more comprehensive classes on human memory structure.

  5. Consistency across repeated eyewitness interviews: contrasting police detectives' beliefs with actual eyewitness performance.

    Directory of Open Access Journals (Sweden)

    Alana C Krix

    Full Text Available In the legal system, inconsistencies in eyewitness accounts are often used to discredit witnesses' credibility. This is at odds with research findings showing that witnesses frequently report reminiscent details (details previously unrecalled at an accuracy rate that is nearly as high as for consistently recalled information. The present study sought to put the validity of beliefs about recall consistency to a test by directly comparing them with actual memory performance in two recall attempts. All participants watched a film of a staged theft. Subsequently, the memory group (N = 84 provided one statement immediately after the film (either with the Self-Administered Interview or free recall and one after a one-week delay. The estimation group (N = 81 consisting of experienced police detectives estimated the recall performance of the memory group. The results showed that actual recall performance was consistently underestimated. Also, a sharp decline of memory performance between recall attempts was assumed by the estimation group whereas actual accuracy remained stable. While reminiscent details were almost as accurate as consistent details, they were estimated to be much less accurate than consistent information and as inaccurate as direct contradictions. The police detectives expressed a great concern that reminiscence was the result of suggestive external influences. In conclusion, it seems that experienced police detectives hold many implicit beliefs about recall consistency that do not correspond with actual recall performance. Recommendations for police trainings are provided. These aim at fostering a differentiated view on eyewitness performance and the inclusion of more comprehensive classes on human memory structure.

  6. Performances of the New Real Time Tsunami Detection Algorithm applied to tide gauges data

    Science.gov (United States)

    Chierici, F.; Embriaco, D.; Morucci, S.

    2017-12-01

    Real-time tsunami detection algorithms play a key role in any Tsunami Early Warning System. We have developed a new algorithm for tsunami detection (TDA) based on the real-time tide removal and real-time band-pass filtering of seabed pressure time series acquired by Bottom Pressure Recorders. The TDA algorithm greatly increases the tsunami detection probability, shortens the detection delay and enhances detection reliability with respect to the most widely used tsunami detection algorithm, while containing the computational cost. The algorithm is designed to be used also in autonomous early warning systems with a set of input parameters and procedures which can be reconfigured in real time. We have also developed a methodology based on Monte Carlo simulations to test the tsunami detection algorithms. The algorithm performance is estimated by defining and evaluating statistical parameters, namely the detection probability, the detection delay, which are functions of the tsunami amplitude and wavelength, and the occurring rate of false alarms. In this work we present the performance of the TDA algorithm applied to tide gauge data. We have adapted the new tsunami detection algorithm and the Monte Carlo test methodology to tide gauges. Sea level data acquired by coastal tide gauges in different locations and environmental conditions have been used in order to consider real working scenarios in the test. We also present an application of the algorithm to the tsunami event generated by Tohoku earthquake on March 11th 2011, using data recorded by several tide gauges scattered all over the Pacific area.

  7. A Robust Motion Artifact Detection Algorithm for Accurate Detection of Heart Rates From Photoplethysmographic Signals Using Time-Frequency Spectral Features.

    Science.gov (United States)

    Dao, Duy; Salehizadeh, S M A; Noh, Yeonsik; Chong, Jo Woon; Cho, Chae Ho; McManus, Dave; Darling, Chad E; Mendelson, Yitzhak; Chon, Ki H

    2017-09-01

    Motion and noise artifacts (MNAs) impose limits on the usability of the photoplethysmogram (PPG), particularly in the context of ambulatory monitoring. MNAs can distort PPG, causing erroneous estimation of physiological parameters such as heart rate (HR) and arterial oxygen saturation (SpO2). In this study, we present a novel approach, "TifMA," based on using the time-frequency spectrum of PPG to first detect the MNA-corrupted data and next discard the nonusable part of the corrupted data. The term "nonusable" refers to segments of PPG data from which the HR signal cannot be recovered accurately. Two sequential classification procedures were included in the TifMA algorithm. The first classifier distinguishes between MNA-corrupted and MNA-free PPG data. Once a segment of data is deemed MNA-corrupted, the next classifier determines whether the HR can be recovered from the corrupted segment or not. A support vector machine (SVM) classifier was used to build a decision boundary for the first classification task using data segments from a training dataset. Features from time-frequency spectra of PPG were extracted to build the detection model. Five datasets were considered for evaluating TifMA performance: (1) and (2) were laboratory-controlled PPG recordings from forehead and finger pulse oximeter sensors with subjects making random movements, (3) and (4) were actual patient PPG recordings from UMass Memorial Medical Center with random free movements and (5) was a laboratory-controlled PPG recording dataset measured at the forehead while the subjects ran on a treadmill. The first dataset was used to analyze the noise sensitivity of the algorithm. Datasets 2-4 were used to evaluate the MNA detection phase of the algorithm. The results from the first phase of the algorithm (MNA detection) were compared to results from three existing MNA detection algorithms: the Hjorth, kurtosis-Shannon entropy, and time-domain variability-SVM approaches. This last is an approach

  8. Cultural values and performance appraisal: assessing the effects of rater self-construal on performance ratings.

    Science.gov (United States)

    Mishra, Vipanchi; Roch, Sylvia G

    2013-01-01

    Much of the prior research investigating the influence of cultural values on performance ratings has focused either on conducting cross-national comparisons among raters or using cultural level individualism/collectivism scales to measure the effects of cultural values on performance ratings. Recent research has shown that there is considerable within country variation in cultural values, i.e. people in one country can be more individualistic or collectivistic in nature. Taking the latter perspective, the present study used Markus and Kitayama's (1991) conceptualization of independent and interdependent self-construals as measures of individual variations in cultural values to investigate within culture variations in performance ratings. Results suggest that rater self-construal has a significant influence on overall performance evaluations; specifically, raters with a highly interdependent self-construal tend to show a preference for interdependent ratees, whereas raters high on independent self-construal do not show a preference for specific type of ratees when making overall performance evaluations. Although rater self-construal significantly influenced overall performance evaluations, no such effects were observed for specific dimension ratings. Implications of these results for performance appraisal research and practice are discussed.

  9. Ten-year detection rate of brain arteriovenous malformations in a large, multiethnic, defined population.

    Science.gov (United States)

    Gabriel, Rodney A; Kim, Helen; Sidney, Stephen; McCulloch, Charles E; Singh, Vineeta; Johnston, S Claiborne; Ko, Nerissa U; Achrol, Achal S; Zaroff, Jonathan G; Young, William L

    2010-01-01

    To evaluate whether increased neuroimaging use is associated with increased brain arteriovenous malformation (BAVM) detection, we examined detection rates in the Kaiser Permanente Medical Care Program of northern California between 1995 and 2004. We reviewed medical records, radiology reports, and administrative databases to identify BAVMs, intracranial aneurysms (IAs: subarachnoid hemorrhage [SAH] and unruptured aneurysms), and other vascular malformations (OVMs: dural fistulas, cavernous malformations, Vein of Galen malformations, and venous malformations). Poisson regression (with robust standard errors) was used to test for trend. Random-effects meta-analysis generated a pooled measure of BAVM detection rate from 6 studies. We identified 401 BAVMs (197 ruptured, 204 unruptured), 570 OVMs, and 2892 IAs (2079 SAHs and 813 unruptured IAs). Detection rates per 100 000 person-years were 1.4 (95% CI, 1.3 to 1.6) for BAVMs, 2.0 (95% CI, 1.8 to 2.3) for OVMs, and 10.3 (95% CI, 9.9 to 10.7) for IAs. Neuroimaging utilization increased 12% per year during the time period (PIAs (PIAs (P4) per 100 000 person-years, without heterogeneity between studies (P=0.25). Rates for BAVMs, OVMs, and IAs in this large, multiethnic population were similar to those in other series. During 1995 to 2004, a period of increasing neuroimaging utilization, we did not observe an increased rate of detection of unruptured BAVMs, despite increased detection of unruptured IAs.

  10. Market Concentration Rate and Market Performance of China’s Swine Industry

    Institute of Scientific and Technical Information of China (English)

    Jia ZHANG; Yucheng HE

    2016-01-01

    Empirical study on market concentration rate and market performance of China’s Swine Industry indicates that higher market concentration rate brings higher overall performance of swine industry. There exists no obvious causal relation between market concentration rate and market performance,but market performance is highly correlated with market concentration rate. The improvement in performance of swine industry is dependent on further optimization of market concentration rate and other factors.

  11. Disclosure of Individual Surgeon's Performance Rates During Informed Consent

    Science.gov (United States)

    Burger, Ingrid; Schill, Kathryn; Goodman, Steven

    2007-01-01

    Objective: The purpose of the paper is to examine the ethical arguments for and against disclosing surgeon-specific performance rates to patients during informed consent, and to examine the challenges that generating and using performance rates entail. Methods: Ethical, legal, and statistical theory is explored to approach the question of whether, when, and how surgeons should disclosure their personal performance rates to patients. The main ethical question addressed is what type of information surgeons owe their patients during informed consent. This question comprises 3 related, ethically relevant considerations that are explored in detail: 1) Does surgeon-specific performance information enhance patient decision-making? 2) Do patients want this type of information? 3) How do the potential benefits of disclosure balance against the risks? Results: Calculating individual performance measures requires tradeoffs and involves inherent uncertainty. There is a lack of evidence regarding whether patients want this information, whether it facilitates their decision-making for surgery, and how it is best communicated to them. Disclosure of personal performance rates during informed consent has the potential benefits of enhancing patient autonomy, improving patient decision-making, and improving quality of care. The major risks of disclosure include inaccurate and misleading performance rates, avoidance of high-risk cases, unjust damage to surgeon's reputations, and jeopardized patient trust. Conclusion: At this time, we think that, for most conditions, surgical procedures, and outcomes, the accuracy of surgeon- and patient-specific performance rates is illusory, obviating the ethical obligation to communicate them as part of the informed consent process. Nonetheless, the surgical profession has the duty to develop information systems that allow for performance to be evaluated to a high degree of accuracy. In the meantime, patients should be informed of the quantity of

  12. Technological advances for improving adenoma detection rates: The changing face of colonoscopy.

    Science.gov (United States)

    Ishaq, Sauid; Siau, Keith; Harrison, Elizabeth; Tontini, Gian Eugenio; Hoffman, Arthur; Gross, Seth; Kiesslich, Ralf; Neumann, Helmut

    2017-07-01

    Worldwide, colorectal cancer is the third commonest cancer. Over 90% follow an adenoma-to-cancer sequence over many years. Colonoscopy is the gold standard method for cancer screening and early adenoma detection. However, considerable variation exists between endoscopists' detection rates. This review considers the effects of different endoscopic techniques on adenoma detection. Two areas of technological interest were considered: (1) optical technologies and (2) mechanical technologies. Optical solutions, including FICE, NBI, i-SCAN and high definition colonoscopy showed mixed results. In contrast, mechanical advances, such as cap-assisted colonoscopy, FUSE, EndoCuff and G-EYE™, showed promise, with reported detections rates of up to 69%. However, before definitive recommendations can be made for their incorporation into daily practice, further studies and comparison trials are required. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  13. High-Performance Signal Detection for Adverse Drug Events using MapReduce Paradigm.

    Science.gov (United States)

    Fan, Kai; Sun, Xingzhi; Tao, Ying; Xu, Linhao; Wang, Chen; Mao, Xianling; Peng, Bo; Pan, Yue

    2010-11-13

    Post-marketing pharmacovigilance is important for public health, as many Adverse Drug Events (ADEs) are unknown when those drugs were approved for marketing. However, due to the large number of reported drugs and drug combinations, detecting ADE signals by mining these reports is becoming a challenging task in terms of computational complexity. Recently, a parallel programming model, MapReduce has been introduced by Google to support large-scale data intensive applications. In this study, we proposed a MapReduce-based algorithm, for common ADE detection approach, Proportional Reporting Ratio (PRR), and tested it in mining spontaneous ADE reports from FDA. The purpose is to investigate the possibility of using MapReduce principle to speed up biomedical data mining tasks using this pharmacovigilance case as one specific example. The results demonstrated that MapReduce programming model could improve the performance of common signal detection algorithm for pharmacovigilance in a distributed computation environment at approximately liner speedup rates.

  14. Routine perinatal and paediatric post-mortem radiography: detection rates and implications for practice

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen J. [NHS Foundation Trust, Department of Radiology Great Ormond Street Hospital for Children, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom); Calder, Alistair D. [NHS Foundation Trust, Department of Radiology Great Ormond Street Hospital for Children, London (United Kingdom); Kiho, Liina [Camelia Botnar Laboratories Great Ormond Street Hospital for Children, Department of Paediatric Pathology, London (United Kingdom); Taylor, Andrew M. [Great Ormond Street Hospital for Children, Cardiorespiratory Unit, London (United Kingdom); UCL Institute of Cardiovascular Science, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom); Sebire, Neil J. [Camelia Botnar Laboratories Great Ormond Street Hospital for Children, Department of Paediatric Pathology, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom)

    2014-03-15

    Routine perinatal and paediatric post-mortem plain radiography allows for the diagnosis and assessment of skeletal dysplasias, fractures and other bony abnormalities. The aim of this study was to review the diagnostic yield of this practice. We identified 1,027 cases performed in a single institution over a 21/2-year period, including babygrams (whole-body examinations) and full skeletal surveys. Images were reported prior to autopsy in all cases. Radiology findings were cross-referenced with the autopsy findings using an autopsy database. We scored each case from 0 to 4 according to the level of diagnostic usefulness. The overall abnormality rate was 126/1,027 (12.3%). There was a significantly higher rate of abnormality when a skeletal survey was performed (18%) rather than a babygram (10%; P < 0.01); 90% (665/739) of babygrams were normal. Of the 74 abnormal babygrams, we found 33 incidental non-contributory cases, 19 contributory, 20 diagnostic, and 2 false-positive cases. There were only 2 cases out of 739 (0.27%) in whom routine post-mortem imaging identified potentially significant abnormalities that would not have been detected if only selected imaging had been performed. A policy of performing selected, rather than routine, foetal post-mortem radiography could result in a significant cost saving. Routine post-mortem paediatric radiography in foetuses and neonates is neither diagnostically useful nor cost-effective. A more evidence-based, selective protocol should yield significant cost savings. (orig.)

  15. Routine perinatal and paediatric post-mortem radiography: detection rates and implications for practice

    International Nuclear Information System (INIS)

    Arthurs, Owen J.; Calder, Alistair D.; Kiho, Liina; Taylor, Andrew M.; Sebire, Neil J.

    2014-01-01

    Routine perinatal and paediatric post-mortem plain radiography allows for the diagnosis and assessment of skeletal dysplasias, fractures and other bony abnormalities. The aim of this study was to review the diagnostic yield of this practice. We identified 1,027 cases performed in a single institution over a 21/2-year period, including babygrams (whole-body examinations) and full skeletal surveys. Images were reported prior to autopsy in all cases. Radiology findings were cross-referenced with the autopsy findings using an autopsy database. We scored each case from 0 to 4 according to the level of diagnostic usefulness. The overall abnormality rate was 126/1,027 (12.3%). There was a significantly higher rate of abnormality when a skeletal survey was performed (18%) rather than a babygram (10%; P < 0.01); 90% (665/739) of babygrams were normal. Of the 74 abnormal babygrams, we found 33 incidental non-contributory cases, 19 contributory, 20 diagnostic, and 2 false-positive cases. There were only 2 cases out of 739 (0.27%) in whom routine post-mortem imaging identified potentially significant abnormalities that would not have been detected if only selected imaging had been performed. A policy of performing selected, rather than routine, foetal post-mortem radiography could result in a significant cost saving. Routine post-mortem paediatric radiography in foetuses and neonates is neither diagnostically useful nor cost-effective. A more evidence-based, selective protocol should yield significant cost savings. (orig.)

  16. A Comparative Survey of Methods for Remote Heart Rate Detection From Frontal Face Videos

    Directory of Open Access Journals (Sweden)

    Chen Wang

    2018-05-01

    Full Text Available Remotely measuring physiological activity can provide substantial benefits for both the medical and the affective computing applications. Recent research has proposed different methodologies for the unobtrusive detection of heart rate (HR using human face recordings. These methods are based on subtle color changes or motions of the face due to cardiovascular activities, which are invisible to human eyes but can be captured by digital cameras. Several approaches have been proposed such as signal processing and machine learning. However, these methods are compared with different datasets, and there is consequently no consensus on method performance. In this article, we describe and evaluate several methods defined in literature, from 2008 until present day, for the remote detection of HR using human face recordings. The general HR processing pipeline is divided into three stages: face video processing, face blood volume pulse (BVP signal extraction, and HR computation. Approaches presented in the paper are classified and grouped according to each stage. At each stage, algorithms are analyzed and compared based on their performance using the public database MAHNOB-HCI. Results found in this article are limited on MAHNOB-HCI dataset. Results show that extracted face skin area contains more BVP information. Blind source separation and peak detection methods are more robust with head motions for estimating HR.

  17. Loss of Excitation Detection in Doubly Fed Induction Generator by Voltage and Reactive Power Rate

    Directory of Open Access Journals (Sweden)

    M. J. Abbasi

    2016-12-01

    Full Text Available The doubly fed induction generator (DFIG is one of the most popular technologies used in wind power systems. With the growing use of DFIGs and increasing power system dependence on them in recent years, protecting of these generators against internal faults is more considered. Loss of excitation (LOE event is among the most frequent failures in electric generators. However, LOE detection studies heretofore were usually confined to synchronous generators. Common LOE detection methods are based on impedance trajectory which makes the system slow and also prone to interpret a stable power swing (SPS as a LOE fault. This paper suggests a new method to detect the LOE based on the measured variables from the DFIG terminal. In this combined method for LOE detection, the rate of change of both the terminal voltage and the output reactive power are utilized and for SPS detection, the fast Fourier transform (FFT analysis of the output instantaneous active power has been used. The performance of the proposed method was evaluated using Matlab/Simulink interface for various power capacities and operating conditions. The results proved the method's quickness, simplicity and security.

  18. Global parameter optimization for maximizing radioisotope detection probabilities at fixed false alarm rates

    Energy Technology Data Exchange (ETDEWEB)

    Portnoy, David, E-mail: david.portnoy@jhuapl.edu [Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Feuerbach, Robert; Heimberg, Jennifer [Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States)

    2011-10-01

    Today there is a tremendous amount of interest in systems that can detect radiological or nuclear threats. Many of these systems operate in extremely high throughput situations where delays caused by false alarms can have a significant negative impact. Thus, calculating the tradeoff between detection rates and false alarm rates is critical for their successful operation. Receiver operating characteristic (ROC) curves have long been used to depict this tradeoff. The methodology was first developed in the field of signal detection. In recent years it has been used increasingly in machine learning and data mining applications. It follows that this methodology could be applied to radiological/nuclear threat detection systems. However many of these systems do not fit into the classic principles of statistical detection theory because they tend to lack tractable likelihood functions and have many parameters, which, in general, do not have a one-to-one correspondence with the detection classes. This work proposes a strategy to overcome these problems by empirically finding parameter values that maximize the probability of detection for a selected number of probabilities of false alarm. To find these parameter values a statistical global optimization technique that seeks to estimate portions of a ROC curve is proposed. The optimization combines elements of simulated annealing with elements of genetic algorithms. Genetic algorithms were chosen because they can reduce the risk of getting stuck in local minima. However classic genetic algorithms operate on arrays of Booleans values or bit strings, so simulated annealing is employed to perform mutation in the genetic algorithm. The presented initial results were generated using an isotope identification algorithm developed at Johns Hopkins University Applied Physics Laboratory. The algorithm has 12 parameters: 4 real-valued and 8 Boolean. A simulated dataset was used for the optimization study; the 'threat' set of

  19. Global parameter optimization for maximizing radioisotope detection probabilities at fixed false alarm rates

    International Nuclear Information System (INIS)

    Portnoy, David; Feuerbach, Robert; Heimberg, Jennifer

    2011-01-01

    Today there is a tremendous amount of interest in systems that can detect radiological or nuclear threats. Many of these systems operate in extremely high throughput situations where delays caused by false alarms can have a significant negative impact. Thus, calculating the tradeoff between detection rates and false alarm rates is critical for their successful operation. Receiver operating characteristic (ROC) curves have long been used to depict this tradeoff. The methodology was first developed in the field of signal detection. In recent years it has been used increasingly in machine learning and data mining applications. It follows that this methodology could be applied to radiological/nuclear threat detection systems. However many of these systems do not fit into the classic principles of statistical detection theory because they tend to lack tractable likelihood functions and have many parameters, which, in general, do not have a one-to-one correspondence with the detection classes. This work proposes a strategy to overcome these problems by empirically finding parameter values that maximize the probability of detection for a selected number of probabilities of false alarm. To find these parameter values a statistical global optimization technique that seeks to estimate portions of a ROC curve is proposed. The optimization combines elements of simulated annealing with elements of genetic algorithms. Genetic algorithms were chosen because they can reduce the risk of getting stuck in local minima. However classic genetic algorithms operate on arrays of Booleans values or bit strings, so simulated annealing is employed to perform mutation in the genetic algorithm. The presented initial results were generated using an isotope identification algorithm developed at Johns Hopkins University Applied Physics Laboratory. The algorithm has 12 parameters: 4 real-valued and 8 Boolean. A simulated dataset was used for the optimization study; the 'threat' set of spectra

  20. Global parameter optimization for maximizing radioisotope detection probabilities at fixed false alarm rates

    Science.gov (United States)

    Portnoy, David; Feuerbach, Robert; Heimberg, Jennifer

    2011-10-01

    Today there is a tremendous amount of interest in systems that can detect radiological or nuclear threats. Many of these systems operate in extremely high throughput situations where delays caused by false alarms can have a significant negative impact. Thus, calculating the tradeoff between detection rates and false alarm rates is critical for their successful operation. Receiver operating characteristic (ROC) curves have long been used to depict this tradeoff. The methodology was first developed in the field of signal detection. In recent years it has been used increasingly in machine learning and data mining applications. It follows that this methodology could be applied to radiological/nuclear threat detection systems. However many of these systems do not fit into the classic principles of statistical detection theory because they tend to lack tractable likelihood functions and have many parameters, which, in general, do not have a one-to-one correspondence with the detection classes. This work proposes a strategy to overcome these problems by empirically finding parameter values that maximize the probability of detection for a selected number of probabilities of false alarm. To find these parameter values a statistical global optimization technique that seeks to estimate portions of a ROC curve is proposed. The optimization combines elements of simulated annealing with elements of genetic algorithms. Genetic algorithms were chosen because they can reduce the risk of getting stuck in local minima. However classic genetic algorithms operate on arrays of Booleans values or bit strings, so simulated annealing is employed to perform mutation in the genetic algorithm. The presented initial results were generated using an isotope identification algorithm developed at Johns Hopkins University Applied Physics Laboratory. The algorithm has 12 parameters: 4 real-valued and 8 Boolean. A simulated dataset was used for the optimization study; the "threat" set of spectra

  1. Use of Selective Fungal Culture Media Increases Rates of Detection of Fungi in the Respiratory Tract of Cystic Fibrosis Patients.

    Science.gov (United States)

    Hong, Gina; Miller, Heather B; Allgood, Sarah; Lee, Richard; Lechtzin, Noah; Zhang, Sean X

    2017-04-01

    The prevalence of fungi in the respiratory tracts of cystic fibrosis (CF) patients has risen. However, fungal surveillance is not routinely performed in most clinical centers in the United States, which may lead to an underestimation of the true prevalence of the problem. We conducted a prospective study comparing the rates of detection for clinically important fungi (CIF), defined as Aspergillus , Scedosporium , and Trichosporon species and Exophiala dermatitidis , in CF sputa using standard bacterial and selective fungal culture media, including Sabouraud dextrose agar with gentamicin (SDA), inhibitory mold agar (IMA), and brain heart infusion (BHI) agar with chloramphenicol and gentamicin. We described the prevalence of these fungi in an adult CF population. A total of 487 CF respiratory samples were collected from 211 unique participants. CIF were detected in 184 (37.8%) samples. Only 26.1% of CIF-positive samples were detected in bacterial culture medium, whereas greater rates of detection for fungi were found in IMA (65.8%; P culture media and longer incubation periods yielded higher rates of detection for CIF in CF sputum samples compared with that detected in bacterial culture medium, resulting in an underdetection of fungi by bacterial culture alone. The prevalence of fungi in CF may be better estimated by using selective fungal culture media, and this may translate to important clinical decisions. Copyright © 2017 American Society for Microbiology.

  2. Thin film organic photodetectors for indirect X-ray detection demonstrating low dose rate sensitivity at low voltage operation

    Energy Technology Data Exchange (ETDEWEB)

    Starkenburg, Daken J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA; Johns, Paul M. [Nuclear Engineering Program, University of Florida, Gainesville, Florida 32611, USA; Detection Systems Group, Pacific Northwest National Laboratory, Richland, Washington 99354, USA; Baciak, James E. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA; Nuclear Engineering Program, University of Florida, Gainesville, Florida 32611, USA; Nino, Juan C. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA; Xue, Jiangeng [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA

    2017-12-14

    Developments in the field of organic semiconductors have generated organic photodetectors with high quantum efficiency, wide spectral sensitivity, low power consumption, and unique form factors that are flexible and conformable to their substrate shape. In this work, organic photodetectors coupled with inorganic CsI(Tl) scintillators are used to showcase the low dose rate sensitivity that is enabled when high performance organic photodetectors and scintillator crystals are integrated. The detection capability of these organic-inorganic coupled systems to high energy radiation highlights their potential as an alternative to traditional photomultiplier tubes for nuclear spectroscopy applications. When exposed to Bremsstrahlung radiation produced from an X-ray generator, SubPc:C60, AlPcCl:C70, and P3HT:PC61BM thin film photodetectors with active layer thicknesses less than 100 nm show detection of incident radiation at low and no applied bias. Remarkably low dose rates, down to at least 0.28 µGy/s, were detectable with a characteristic linear relationship between exposure rate and photodetector current output. These devices also demonstrate sensitivities as high as 5.37 mC Gy-1 cm-2 when coupled to CsI(Tl). Additionally, as the tube voltage across the X-ray generator was varied, these organic-inorganic systems showed their ability to detect a range of continuous radiation spectra spanning several hundred keV.

  3. Thin film organic photodetectors for indirect X-ray detection demonstrating low dose rate sensitivity at low voltage operation

    Science.gov (United States)

    Starkenburg, Daken J.; Johns, Paul M.; Baciak, James E.; Nino, Juan C.; Xue, Jiangeng

    2017-12-01

    Developments in the field of organic semiconductors have generated organic photodetectors with high quantum efficiency, wide spectral sensitivity, low power consumption, and unique form factors that are flexible and conformable to their substrate shape. In this work, organic photodetectors coupled with inorganic CsI(Tl) scintillators are used to showcase the low dose rate sensitivity that is enabled when high performance organic photodetectors and scintillator crystals are integrated. The detection capability of these organic-inorganic coupled systems to high energy radiation highlights their potential as an alternative to traditional photomultiplier tubes for nuclear spectroscopy applications. When exposed to Bremsstrahlung radiation produced from an X-ray generator, SubPc:C60, AlPcCl:C70, and P3HT:PC61BM thin film photodetectors with active layer thicknesses less than 100 nm show detection of incident radiation at low and no applied bias. Remarkably low dose rates, down to at least 0.18 μGy/s, were detectable with a characteristic linear relationship between exposure rate and photodetector current output. These devices also demonstrate sensitivities as high as 5.37 mC Gy-1 cm-2 when coupled to CsI(Tl). Additionally, as the tube voltage across the X-ray generator was varied, these organic-inorganic systems showed their ability to detect a range of continuous radiation spectra spanning several hundred keV.

  4. The Detection and Correction of Bias in Student Ratings of Instruction.

    Science.gov (United States)

    Haladyna, Thomas; Hess, Robert K.

    1994-01-01

    A Rasch model was used to detect and correct bias in Likert rating scales used to assess student perceptions of college teaching, using a database of ratings. Statistical corrections were significant, supporting the model's potential utility. Recommendations are made for a theoretical rationale and further research on the model. (Author/MSE)

  5. Phenobarbital reduces EEG amplitude and propagation of neonatal seizures but does not alter performance of automated seizure detection.

    Science.gov (United States)

    Mathieson, Sean R; Livingstone, Vicki; Low, Evonne; Pressler, Ronit; Rennie, Janet M; Boylan, Geraldine B

    2016-10-01

    Phenobarbital increases electroclinical uncoupling and our preliminary observations suggest it may also affect electrographic seizure morphology. This may alter the performance of a novel seizure detection algorithm (SDA) developed by our group. The objectives of this study were to compare the morphology of seizures before and after phenobarbital administration in neonates and to determine the effect of any changes on automated seizure detection rates. The EEGs of 18 term neonates with seizures both pre- and post-phenobarbital (524 seizures) administration were studied. Ten features of seizures were manually quantified and summary measures for each neonate were statistically compared between pre- and post-phenobarbital seizures. SDA seizure detection rates were also compared. Post-phenobarbital seizures showed significantly lower amplitude (pphenobarbital reduces both the amplitude and propagation of seizures which may help to explain electroclinical uncoupling of seizures. The seizure detection rate of the algorithm was unaffected by these changes. The results suggest that users should not need to adjust the SDA sensitivity threshold after phenobarbital administration. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Dedicated Barrett's surveillance sessions managed by trained endoscopists improve dysplasia detection rate.

    Science.gov (United States)

    Ooi, Joanne; Wilson, Patrick; Walker, Giles; Blaker, Paul; DeMartino, Sabina; O'Donohue, John; Reffitt, David; Lanaspre, Effie; Chang, Fuju; Meenan, John; Dunn, Jason M

    2017-06-01

    Background and study aim  Barrett's esophagus (BE)-associated dysplasia is an important marker for risk of progression to esophageal adenocarcinoma (EAC) and an indication for endoscopic therapy. However, BE surveillance technique is variable. The aim of this study was to assess the effect of dedicated BE surveillance lists on dysplasia detection rate (DDR). Patients and methods  This was a prospective study of patients undergoing BE surveillance at two hospitals - community (UHL) and upper gastrointestinal center (GSTT). Four endoscopists (Group A) were trained in Prague classification, Seattle protocol biopsy technique, and lesion detection prior to performing BE surveillance endoscopies at both sites, with dedicated time slots or lists. The DDR was then compared with historical data from 47 different endoscopists at GSTT and 24 at UHL (Group B) who had undertaken Barrett's surveillance over the preceding 5-year period. Results  A total of 729 patients with BE underwent surveillance endoscopy between 2007 and 2012. There was no significant difference in patient age, sex, or length of BE between the two groups. There was a significant difference in detection rate of confirmed indefinite or low grade dysplasia and high grade dysplasia (HGD)/EAC between the two groups: 18 % (26 /142) Group A vs. 8 % (45/587) in Group B ( P  < 0.001). Documentation of Prague criteria and adherence to the Seattle protocol was significantly higher in Group A. Conclusion  This study demonstrated that a group of trained endoscopists undertaking Barrett's surveillance on dedicated lists had significantly higher DDR than a nonspecialist cohort. These findings support the introduction of dedicated Barrett's surveillance lists. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Anti-correlations in the degree distribution increase stimulus detection performance in noisy spiking neural networks.

    Science.gov (United States)

    Martens, Marijn B; Houweling, Arthur R; E Tiesinga, Paul H

    2017-02-01

    Neuronal circuits in the rodent barrel cortex are characterized by stable low firing rates. However, recent experiments show that short spike trains elicited by electrical stimulation in single neurons can induce behavioral responses. Hence, the underlying neural networks provide stability against internal fluctuations in the firing rate, while simultaneously making the circuits sensitive to small external perturbations. Here we studied whether stability and sensitivity are affected by the connectivity structure in recurrently connected spiking networks. We found that anti-correlation between the number of afferent (in-degree) and efferent (out-degree) synaptic connections of neurons increases stability against pathological bursting, relative to networks where the degrees were either positively correlated or uncorrelated. In the stable network state, stimulation of a few cells could lead to a detectable change in the firing rate. To quantify the ability of networks to detect the stimulation, we used a receiver operating characteristic (ROC) analysis. For a given level of background noise, networks with anti-correlated degrees displayed the lowest false positive rates, and consequently had the highest stimulus detection performance. We propose that anti-correlation in the degree distribution may be a computational strategy employed by sensory cortices to increase the detectability of external stimuli. We show that networks with anti-correlated degrees can in principle be formed by applying learning rules comprised of a combination of spike-timing dependent plasticity, homeostatic plasticity and pruning to networks with uncorrelated degrees. To test our prediction we suggest a novel experimental method to estimate correlations in the degree distribution.

  8. Developing a Digital Medicine System in Psychiatry: Ingestion Detection Rate and Latency Period.

    Science.gov (United States)

    Profit, Deborah; Rohatagi, Shashank; Zhao, Cathy; Hatch, Ainslie; Docherty, John P; Peters-Strickland, Timothy S

    2016-09-01

    A digital medicine system (DMS) has been developed to measure and report adherence to an atypical antipsychotic, aripiprazole, in psychiatric patients. The DMS consists of 3 components: ingestible sensor embedded in a medication tablet, wearable sensor, and secure mobile and cloud-based applications. An umbrella study protocol was designed to rapidly assess the technical performance and safety of the DMS in multiple substudies to guide the technology development. Two sequential substudies enrolled 30 and 29 healthy volunteers between March-April 2014 and February-March 2015, respectively, to assess detection accuracy of the ingestible sensor by the DMS and the latency period between ingestion and detection of the ingestion by the wearable sensor or the cloud-based server. The first substudy identified areas for improvement using early versions of the wearable sensor and the mobile application. The second substudy tested updated versions of the components and showed an overall ingestion detection rate of 96.6%. Mean latency times for the signal transmission were 1.1-1.3 minutes (from ingestion to the wearable sensor detection) and 6.2-10.3 minutes (from the wearable sensor detection to the server detection). Half of transmissions were completed in < 2 minutes, and ~90% of ingestions were registered by the smartphone within 30 minutes of ingestion. No serious adverse events, discontinuations, or clinically significant laboratory/vital signs findings were reported. The DMS implementing modified versions of the smartphone application and the wearable sensor has the technical capability to detect and report tablet ingestion with high accuracy and acceptable latency time. ClinicalTrials.gov identifier: NCT02091882. © Copyright 2016 Physicians Postgraduate Press, Inc.

  9. Adaptive heart rate-based epileptic seizure detection using real-time user feedback

    DEFF Research Database (Denmark)

    De Cooman, Thomas; Kjær, Troels Wesenberg; Van Huffel, Sabine

    2017-01-01

    Automated seizure detection in a home environment has been of increased interest the last couple of decades. Heart rate-based seizure detection is a way to detect temporal lobe epilepsy seizures at home, but patient-independent algorithms showed to be insufficiently accurate due to the high patient...... with incorrect user feedback, making it ideal for implementation in a home environment for a seizure warning system....

  10. A Compound Detection System Based on Ultrasonic Flow Rate and Concentration

    OpenAIRE

    Qing-Hui WANG; Fang MU; Li-Feng WEI

    2014-01-01

    This paper proposes a new detection system for monitoring gas concentration and flow rate. Velocity difference of ultrasonic wave in bi-directional propagation in measured gas is recorded and utilized for computing the online gas concentration and flow rate. Meanwhile, the temperature compensation, return signal processing and error analysis algorithms are applied to improve the accuracy. The experimental results show that, compared with the single sensor measurement of gas flow rate or conce...

  11. Effects of Rating Purpose and Rater Self-Esteem on Performance Ratings.

    Science.gov (United States)

    1983-03-01

    examined in a laboratory study, using a 2x2 analysis of variance design. Results indicate that low self - esteem raters assign significantly higher...design. Results indicate that low self - esteem raters assign significantly higher performance ratings when performance appraisal information will be used...studies indicated that individuals low in self - esteem have less self -confidence, feel less competent, and rely more on others’ opinions than do individuals

  12. Social motivation in prospective memory: higher importance ratings and reported performance rates for social tasks.

    Science.gov (United States)

    Penningroth, Suzanna L; Scott, Walter D; Freuen, Margaret

    2011-03-01

    Few studies have addressed social motivation in prospective memory (PM). In a pilot study and two main studies, we examined whether social PM tasks possess a motivational advantage over nonsocial PM tasks. In the pilot study and Study 1, participants listed their real-life important and less important PM tasks. Independent raters categorized the PM tasks as social or nonsocial. Results from both studies showed a higher proportion of tasks rated as social when important tasks were requested than when less important tasks were requested. In Study 1, participants also reported whether they had remembered to perform each PM task. Reported performance rates were higher for tasks rated as social than for those rated as nonsocial. Finally, in Study 2, participants rated the importance of two hypothetical PM tasks, one social and one nonsocial. The social PM task was rated higher in importance. Overall, these findings suggest that social PM tasks are viewed as more important than nonsocial PM tasks and they are more likely to be performed. We propose that consideration of the social relevance of PM will lead to a more complete and ecologically valid theoretical description of PM performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  13. PERFORMANCE COMPARISON OF INTRUSION DETECTION SYSTEM USING VARIOUS TECHNIQUES – A REVIEW

    Directory of Open Access Journals (Sweden)

    S. Devaraju

    2013-09-01

    Full Text Available Nowadays, the security has become a critical part of any organization or industry information systems. The Intrusion Detection System is an effective method to deal with the new kind of threats such as DoS, Porbe, R2L and U2R. In this paper, we analyze the various approaches such as Hidden Semi Markov Model, Conditional Random Fields and Layered Approach, Bayesian classification, Data Mining techniques, Clustering Algorithms such as K-Means and Fuzzy c-Means, Back Propagation Neural Network, SOM Neural Network, Rough Set Neural Network Algorithm, Genetic Algorithm, Pattern Matching, Principle Component Analysis, Linear Discriminant Analysis, Independent Component Analysis, Multivariate Statistical Analysis, SOM/PSO algorithm etc. The performance is measured for two different datasets using various approaches. The datasets are trained and tested for identifying the new attacks that will affect the hosts or networks. The well known KDD Cup 1999 or DARPA 1999 dataset has been used to improve the accuracy and performance. The four groups of attacks are identified as Probe, DoS, U2R and R2L. The dataset used for training set is 494,021 and testing set is 311,028. The aim is to improve the detection rate and performance of the proposed system.

  14. Heart Rate Detection Using Microsoft Kinect: Validation and Comparison to Wearable Devices.

    Science.gov (United States)

    Gambi, Ennio; Agostinelli, Angela; Belli, Alberto; Burattini, Laura; Cippitelli, Enea; Fioretti, Sandro; Pierleoni, Paola; Ricciuti, Manola; Sbrollini, Agnese; Spinsante, Susanna

    2017-08-02

    Contactless detection is one of the new frontiers of technological innovation in the field of healthcare, enabling unobtrusive measurements of biomedical parameters. Compared to conventional methods for Heart Rate (HR) detection that employ expensive and/or uncomfortable devices, such as the Electrocardiograph (ECG) or pulse oximeter, contactless HR detection offers fast and continuous monitoring of heart activities and provides support for clinical analysis without the need for the user to wear a device. This paper presents a validation study for a contactless HR estimation method exploiting RGB (Red, Green, Blue) data from a Microsoft Kinect v2 device. This method, based on Eulerian Video Magnification (EVM), Photoplethysmography (PPG) and Videoplethysmography (VPG), can achieve performance comparable to classical approaches exploiting wearable systems, under specific test conditions. The output given by a Holter, which represents the gold-standard device used in the test for ECG extraction, is considered as the ground-truth, while a comparison with a commercial smartwatch is also included. The validation process is conducted with two modalities that differ for the availability of a priori knowledge about the subjects' normal HR. The two test modalities provide different results. In particular, the HR estimation differs from the ground-truth by 2% when the knowledge about the subject's lifestyle and his/her HR is considered and by 3.4% if no information about the person is taken into account.

  15. The Performance of Short-Term Heart Rate Variability in the Detection of Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Fausto Lucena

    2016-01-01

    Full Text Available Congestive heart failure (CHF is a cardiac disease associated with the decreasing capacity of the cardiac output. It has been shown that the CHF is the main cause of the cardiac death around the world. Some works proposed to discriminate CHF subjects from healthy subjects using either electrocardiogram (ECG or heart rate variability (HRV from long-term recordings. In this work, we propose an alternative framework to discriminate CHF from healthy subjects by using HRV short-term intervals based on 256 RR continuous samples. Our framework uses a matching pursuit algorithm based on Gabor functions. From the selected Gabor functions, we derived a set of features that are inputted into a hybrid framework which uses a genetic algorithm and k-nearest neighbour classifier to select a subset of features that has the best classification performance. The performance of the framework is analyzed using both Fantasia and CHF database from Physionet archives which are, respectively, composed of 40 healthy volunteers and 29 subjects. From a set of nonstandard 16 features, the proposed framework reaches an overall accuracy of 100% with five features. Our results suggest that the application of hybrid frameworks whose classifier algorithms are based on genetic algorithms has outperformed well-known classifier methods.

  16. A Comparative Study of Data Mining Algorithms for High Detection Rate in Intrusion Detection System

    Directory of Open Access Journals (Sweden)

    Nabeela Ashraf

    2018-01-01

    Full Text Available Due to the fast growth and tradition of the internet over the last decades, the network security problems are increasing vigorously. Humans can not handle the speed of processes and the huge amount of data required to handle network anomalies. Therefore, it needs substantial automation in both speed and accuracy. Intrusion Detection System is one of the approaches to recognize illegal access and rare attacks to secure networks. In this proposed paper, Naive Bayes, J48 and Random Forest classifiers are compared to compute the detection rate and accuracy of IDS. For experiments, the KDD_NSL dataset is used.

  17. A parametric study of rate of advance and area coverage rate performance of synthetic aperture radar.

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Hensley, Jr., William H. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Burns, Bryan L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Doerry, Armin Walter [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-11-01

    The linear ground distance per unit time and ground area covered per unit time of producing synthetic aperture radar (SAR) imagery, termed rate of advance (ROA) and area coverage rate (ACR), are important metrics for platform and radar performance in surveillance applications. These metrics depend on many parameters of a SAR system such as wavelength, aircraft velocity, resolution, antenna beamwidth, imaging mode, and geometry. Often the effects of these parameters on rate of advance and area coverage rate are non-linear. This report addresses the impact of different parameter spaces as they relate to rate of advance and area coverage rate performance.

  18. ALGORITHMS FOR OPTIMIZATION OF SYSYTEM PERFORMANCE IN LAYERED DETECTION SYSTEMS UNDER DETECTOR COORELATION

    International Nuclear Information System (INIS)

    Wood, Thomas W.; Heasler, Patrick G.; Daly, Don S.

    2010-01-01

    Almost all of the 'architectures' for radiation detection systems in Department of Energy (DOE) and other USG programs rely on some version of layered detector deployment. Efficacy analyses of layered (or more generally extended) detection systems in many contexts often assume statistical independence among detection events and thus predict monotonically increasing system performance with the addition of detection layers. We show this to be a false conclusion for the ROC curves typical of most current technology gamma detectors, and more generally show that statistical independence is often an unwarranted assumption for systems in which there is ambiguity about the objects to be detected. In such systems, a model of correlation among detection events allows optimization of system algorithms for interpretation of detector signals. These algorithms are framed as optimal discriminant functions in joint signal space, and may be applied to gross counting or spectroscopic detector systems. We have shown how system algorithms derived from this model dramatically improve detection probabilities compared to the standard serial detection operating paradigm for these systems. These results would not surprise anyone who has confronted the problem of correlated errors (or failure rates) in the analogous contexts, but is seems to be largely underappreciated among those analyzing the radiation detection problem - independence is widely assumed and experimental studies typical fail to measure correlation. This situation, if not rectified, will lead to several unfortunate results. Including overconfidence in system efficacy, overinvestment in layers of similar technology, and underinvestment in diversity among detection assets.

  19. Performance analysis of EM-based blind detection for ON-OFF keying modulation over atmospheric optical channels

    Science.gov (United States)

    Dabiri, Mohammad Taghi; Sadough, Seyed Mohammad Sajad

    2018-04-01

    In the free-space optical (FSO) links, atmospheric turbulence lead to scintillation in the received signal. Due to its ease of implementation, intensity modulation with direct detection (IM/DD) based on ON-OFF keying (OOK) is a popular signaling scheme in these systems. Over turbulence channel, to detect OOK symbols in a blind way, i.e., without sending pilot symbols, an expectation-maximization (EM)-based detection method was recently proposed in the literature related to free-space optical (FSO) communication. However, the performance of EM-based detection methods severely depends on the length of the observation interval (Ls). To choose the optimum values of Ls at target bit error rates (BER)s of FSO communications which are commonly lower than 10-9, Monte-Carlo simulations would be very cumbersome and require a very long processing time. To facilitate performance evaluation, in this letter we derive the analytic expressions for BER and outage probability. Numerical results validate the accuracy of our derived analytic expressions. Our results may serve to evaluate the optimum value for Ls without resorting to time-consuming Monte-Carlo simulations.

  20. real exchange rate misalignment and economic performance in ...

    African Journals Online (AJOL)

    ... effects of real exchange rate misalignment on economic performance in Nigeria. .... main factors that impacts on real exchange rate in India .... financial assets and ignores non-economic factor such as .... and fiscal policies to control inflation.

  1. Non-contact detection of cardiac rate based on visible light imaging device

    Science.gov (United States)

    Zhu, Huishi; Zhao, Yuejin; Dong, Liquan

    2012-10-01

    We have developed a non-contact method to detect human cardiac rate at a distance. This detection is based on the general lighting condition. Using the video signal of human face region captured by webcam, we acquire the cardiac rate based on the PhotoPlethysmoGraphy theory. In this paper, the cardiac rate detecting method is mainly in view of the blood's different absorptivities of the lights various wavelengths. Firstly, we discompose the video signal into RGB three color signal channels and choose the face region as region of interest to take average gray value. Then, we draw three gray-mean curves on each color channel with time as variable. When the imaging device has good fidelity of color, the green channel signal shows the PhotoPlethysmoGraphy information most clearly. But the red and blue channel signals can provide more other physiological information on the account of their light absorptive characteristics of blood. We divide red channel signal by green channel signal to acquire the pulse wave. With the passband from 0.67Hz to 3Hz as a filter of the pulse wave signal and the frequency spectrum superimposed algorithm, we design frequency extracted algorithm to achieve the cardiac rate. Finally, we experiment with 30 volunteers, containing different genders and different ages. The results of the experiments are all relatively agreeable. The difference is about 2bmp. Through the experiment, we deduce that the PhotoPlethysmoGraphy theory based on visible light can also be used to detect other physiological information.

  2. Conductor and Ensemble Performance Expressivity and State Festival Ratings

    Science.gov (United States)

    Price, Harry E.; Chang, E. Christina

    2005-01-01

    This study is the second in a series examining the relationship between conducting and ensemble performance. The purpose was to further examine the associations among conductor, ensemble performance expressivity, and festival ratings. Participants were asked to rate the expressivity of video-only conducting and parallel audio-only excerpts from a…

  3. Performance Verification on UWB Antennas for Breast Cancer Detection

    Directory of Open Access Journals (Sweden)

    Vijayasarveswari V.

    2017-01-01

    Full Text Available Breast cancer is a common disease among women and death figure is continuing to increase. Early breast cancer detection is very important. Ultra wide-band (UWB is the promising candidate for short communication applications. This paper presents the performance of different types of UWB antennas for breast cancer detection. Two types of antennas are used i.e: UWB pyramidal antenna and UWB horn antenna. These antennas are used to transmit and receive the UWB signal. The collected signals are fed into developed neural network module to measure the performance efficiency of each antenna. The average detection efficiency is 88.46% and 87.55% for UWB pyramidal antenna and UWB horn antenna respectively. These antennas can be used to detect breast cancer in the early stage and save precious lives.

  4. Cost and detection rate of glaucoma screening with imaging devices in a primary care center

    Directory of Open Access Journals (Sweden)

    Anton A

    2017-02-01

    Full Text Available Alfonso Anton,1–4 Monica Fallon,3,5 Francesc Cots,2 María A Sebastian,6 Antonio Morilla-Grasa,4 Sergi Mojal,3 Xavier Castells2 1Medicine School, Universidad Internacional de Cataluña, 2Servei d’Estudies, Parc de Salut Mar, 3Instituto Hospital del Mar de Investigaciones Médicas (IMIM, 4Glaucoma Department, Instituto Catalán de Retina (ICR, 5Universidad Autónoma de Barcelona, 6Centro de Atención Primaria Larrard, Barcelona, Spain Purpose: To analyze the cost and detection rate of a screening program for detecting glaucoma with imaging devices. Materials and methods: In this cross-sectional study, a glaucoma screening program was applied in a population-based sample randomly selected from a population of 23,527. Screening targeted the population at risk of glaucoma. Examinations included optic disk tomography (Heidelberg retina tomograph [HRT], nerve fiber analysis, and tonometry. Subjects who met at least 2 of 3 endpoints (HRT outside normal limits, nerve fiber index ≥30, or tonometry ≥21 mmHg were referred for glaucoma consultation. The currently established (“conventional” detection method was evaluated by recording data from primary care and ophthalmic consultations in the same population. The direct costs of screening and conventional detection were calculated by adding the unit costs generated during the diagnostic process. The detection rate of new glaucoma cases was assessed. Results: The screening program evaluated 414 subjects; 32 cases were referred for glaucoma consultation, 7 had glaucoma, and 10 had probable glaucoma. The current detection method assessed 677 glaucoma suspects in the population, of whom 29 were diagnosed with glaucoma or probable glaucoma. Glaucoma screening and the conventional detection method had detection rates of 4.1% and 3.1%, respectively, and the cost per case detected was 1,410 and 1,435€, respectively. The cost of screening 1 million inhabitants would be 5.1 million euros and would allow

  5. Staff background paper on performance-based rate making

    International Nuclear Information System (INIS)

    Fraser, J.; Brownell, B.

    1998-10-01

    An alternative to the traditional cost of service (COS) regulation for electric utilities in British Columbia has been proposed. The alternative to pure COS regulation is performance-based rate making (PBR). PBR partially decouples a utility's rates from its costs and ties utility profits to performance relative to specific benchmarks. The motivation underlying PBR is that ideally, it provides incentives for utilities to cost-effectively achieve pre-defined goals. This report describes the design of PBR mechanisms, base rate PBR formulas, base rate PBR in other jurisdictions including New York, California, Maine and New Jersey. The report also describes gas procurement PBR in other jurisdictions, as well as British Columbia Utilities' Commission's own experience with PBR. In general, PBR has the potential to provide resource efficiency, allocative efficiency, support for introduction of new services, and reduced regulatory administrative costs. 15 refs., 4 tabs

  6. EUROCAT website data on prenatal detection rates of congenital anomalies

    DEFF Research Database (Denmark)

    Garne, Ester; Dolk, Helen; Loane, Maria

    2010-01-01

    The EUROCAT website www.eurocat-network.eu publishes prenatal detection rates for major congenital anomalies using data from European population-based congenital anomaly registers, covering 28% of the EU population as well as non-EU countries. Data are updated annually. This information can be us...

  7. EUROCAT website data on prenatal detection rates of congenital anomalies

    NARCIS (Netherlands)

    Garne, Ester; Dolk, Helen; Loane, Maria; Boyd, Patricia A.

    2010-01-01

    The EUROCAT website www.eurocat-network.eu publishes prenatal detection rates for major congenital anomalies using data from European population-based congenital anomaly registers, covering 28% of the EU population as well as non-EU countries. Data are updated annually. This information can be

  8. Direct SUSY dark matter detection-theoretical rates due to the spin

    International Nuclear Information System (INIS)

    Vergados, J D

    2004-01-01

    The recent WMAP data have confirmed that exotic dark matter together with the vacuum energy (cosmological constant) dominate in the flat Universe. Thus direct dark matter detection, consisting of detecting the recoiling nucleus, is central to particle physics and cosmology. Supersymmetry provides a natural dark matter candidate, the lightest supersymmetric particle (LSP). The relevant cross sections arise out of two mechanisms: (i) the coherent mode, due to the scalar interaction and (ii) the spin contribution arising from the axial current. In this paper we will focus on the spin contribution, which is expected to dominate for light targets. For both modes it is possible to obtain detectable rates, but in most models the expected rates are much lower than the present experimental goals. So one should exploit two characteristic signatures of the reaction, namely the modulation effect and in directional experiments the correlation of the event rates with the sun's motion. In standard non-directional experiments the modulation is small, less than 2 per cent. In the case of the directional event rates we would like to suggest that the experiments exploit two features of the process, which are essentially independent of the SUSY model employed, namely: (1) the forward-backward asymmetry, with respect to the sun's direction of motion, is very large and (2) the modulation is much larger, especially if the observation is made in a plane perpendicular to the sun's velocity. In this case the difference between maximum and minimum can be larger than 40 per cent and the phase of the earth at the maximum is direction dependent

  9. Drowsiness detection using heart rate variability.

    Science.gov (United States)

    Vicente, José; Laguna, Pablo; Bartra, Ariadna; Bailón, Raquel

    2016-06-01

    It is estimated that 10-30 % of road fatalities are related to drowsy driving. Driver's drowsiness detection based on biological and vehicle signals is being studied in preventive car safety. Autonomous nervous system activity, which can be measured noninvasively from the heart rate variability (HRV) signal obtained from surface electrocardiogram, presents alterations during stress, extreme fatigue and drowsiness episodes. We hypothesized that these alterations manifest on HRV and thus could be used to detect driver's drowsiness. We analyzed three driving databases in which drivers presented different sleep-deprivation levels, and in which each driving minute was annotated as drowsy or awake. We developed two different drowsiness detectors based on HRV. While the drowsiness episodes detector assessed each minute of driving as "awake" or "drowsy" with seven HRV derived features (positive predictive value 0.96, sensitivity 0.59, specificity 0.98 on 3475 min of driving), the sleep-deprivation detector discerned if a driver was suitable for driving or not, at driving onset, as function of his sleep-deprivation state. Sleep-deprivation state was estimated from the first three minutes of driving using only one HRV feature (positive predictive value 0.80, sensitivity 0.62, specificity 0.88 on 30 drivers). Incorporating drowsiness assessment based on HRV signal may add significant improvements to existing car safety systems.

  10. Detection rate of prostate cancer following biopsy among the northern Han Chinese population: a single-center retrospective study of 1022 cases.

    Science.gov (United States)

    Jia, Yong; Zhu, Lei-Yi; Xian, Yu-Xin; Sun, Xiao-Qing; Gao, Jian-Gang; Zhang, Xin-Hong; Hou, Si-Chuan; Zhang, Chang-Cun; Liu, Zhao-Xu

    2017-08-29

    Prostate cancer is known to have ethnic and regional differences. The study aimed to clinically evaluate the detection rate of prostate cancer on transrectal ultrasonography (TRUS)-guided prostate biopsy and analyze its characteristics among the northern Han Chinese population at a single center. Between October 2009 and September 2016, a total of 1027 Chinese men, who had undergone TRUS-guided prostate biopsy at Qingdao Municipal Hospital, were retrospectively analyzed. Prostate biopsies were performed in the case of an abnormally elevated serum PSA level, and/or abnormal digital rectal examination (DRE) findings, and/or suspicious prostatic imaging findings. Of the 1022 men enrolled in the analysis, 438 patients (42.8%) were diagnosed with prostate adenocarcinoma histologically. When serum PSA levels were divided into five subgroups (less than 4.0, 4.0 to 10.0, 10.0 to 20.0, 20.0 to 100.0, and ≥ 100.0 ng/ml), the detection rates of prostate cancer were 12.4, 15.9, 34.1, 66.2, and 93.8%, respectively. With serum PSA levels of 4.0 to 10.0 ng/ml, the cancer detection rates for a normal DRE and a suspect DRE finding were 13.5 and 58.2%, respectively. Accordingly, the cancer detection rates for a normal imaging and a suspect imaging finding were 13.5 and 58.2%, respectively. Besides, a large proportion of the patients were in the clinically advanced stage. The present study data reported a relatively higher prostate cancer detection rate of 42.8% and that the majority of the patients presented with clinically advanced prostate cancers within a local clinical urologic practice. An early detection and screening program for prostate cancer is of great need to reduce the burden from this disease among the northern Han Chinese population.

  11. A preliminary study on the association between ventilation rates in classrooms and student performance.

    Science.gov (United States)

    Shaughnessy, R J; Haverinen-Shaughnessy, U; Nevalainen, A; Moschandreas, D

    2006-12-01

    Poor conditions leading to substandard indoor air quality (IAQ) in classrooms have been frequently cited in the literature over the past two decades. However, there is limited data linking poor IAQ in the classrooms to student performance. Whereas, it is assumed that poor IAQ results in reduced attendance and learning potential, and subsequent poor student performance, validating this hypothesis presents a challenge in today's school environment. This study explores the association between student performance on standardized aptitude tests that are administered to students on a yearly basis, to classroom carbon dioxide (CO2) concentrations, which provide a surrogate of ventilation being provided to each room. Data on classroom CO2 concentrations (over a 4-5 h time span within a typical school day) were recorded in fifth grade classrooms in 54 elementary schools within a school district in the USA. Results from this preliminary study yield a significant (P classroom-level ventilation rate and test results in math. They also indicate that non-linear effects may need to be considered for better representation of the association. A larger sample size is required in order to draw more definitive conclusions. Practical Implications Future studies could focus on (1) gathering more evidence on the possible association between classroom ventilation rates and students' academic performance; (2) the linear/non-linear nature of the association; and (3) whether it is possible to detect 'no observed adverse effect level' for adequate ventilation with respect to academic performance in schools. All of this information could be used to improve guidance and take regulatory actions to ensure adequate ventilation in schools. The high prevalence of low ventilation rates, combined with the growing evidence of the positive impact that sufficient ventilation has on human performance, suggests an opportunity for improving design and management of school facilities.

  12. HPV detection rate in saliva may depend on the immune system efficiency.

    Science.gov (United States)

    Adamopoulou, Maria; Vairaktaris, Eleftherios; Panis, Vassilis; Nkenke, Emeka; Neukam, Friedreich W; Yapijakis, Christos

    2008-01-01

    Human papilloma virus (HPV) has been established as a major etiological factor of anogenital cancer. In addition, HPV has also been implicated in oral carcinogenesis but its detection rates appear to be highly variable, depending on the patient population tested, the molecular methodology used, as well as the type of oral specimen investigated. For example, saliva is an oral fluid that may play a role in HPV transmission, although the detection rates of the virus are lower than tissue. Recent evidence has indicated that HPV-related pathology is increased in the oral cavity of human immunodeficiency virus (HIV)-positive individuals. In order to investigate whether the presence of different HPV types in saliva depends on immune system efficiency, oral fluid samples of patients with oral cancer and without any known immune deficiency were compared with those of HIV-positive individuals. Saliva samples were collected from 68 patients with oral squamous cell carcinoma and 34 HIV seropositive individuals. HPV DNA sequences were detected by L1 concensus polymerase chain reaction (PCR), followed by restriction fragment length polymorphism (RFLP) analysis and DNA sequencing for HPV typing. HPV DNA was detected in 7/68 (10.3%) of the oral cancer patients and in 12/34 (35.3%) of the HIV-positive individuals, a highly significant difference (p = 0.006; odds ratio 4.753; 95% confidence interval 1.698-13.271). Among HPV-positive samples, the prevalence of HPV types associated with high oncogenic risk was similar in oral cancer and HIV-positive cases (71.4% and 66.7%, respectively). In both groups, the most common HPV type was high-risk 16 (50% and 42.8%, respectively). Although a similar pattern of HPV high-risk types was detected in oral cancer and HIV-positive cases, the quantitative detection of HPV in saliva significantly depended on immune system efficiency. Furthermore, the significantly increased detection rates of HPV in saliva of HIV-positive individuals may be

  13. Detecting subsurface fluid leaks in real-time using injection and production rates

    Science.gov (United States)

    Singh, Harpreet; Huerta, Nicolas J.

    2017-12-01

    CO2 injection into geologic formations for either enhanced oil recovery or carbon storage introduces a risk for undesired fluid leakage into overlying groundwater or to the surface. Despite decades of subsurface CO2 production and injection, the technologies and methods for detecting CO2 leaks are still costly and prone to large uncertainties. This is especially true for pressure-based monitoring methods, which require the use of simplified geological and reservoir flow models to simulate the pressure behavior as well as background noise affecting pressure measurements. In this study, we propose a method to detect the time and volume of fluid leakage based on real-time measurements of well injection and production rates. The approach utilizes analogies between fluid flow and capacitance-resistance modeling. Unlike other leak detection methods (e.g. pressure-based), the proposed method does not require geological and reservoir flow models to simulate the behavior that often carry significant sources of uncertainty; therefore, with our approach the leak can be detected with greater certainty. The method can be applied to detect when a leak begins by tracking a departure in fluid production rate from the expected pattern. The method has been tuned to detect the effect of boundary conditions and fluid compressibility on leakage. To highlight the utility of this approach we use our method to detect leaks for two scenarios. The first scenario simulates a fluid leak from the storage formation into an above-zone monitoring interval. The second scenario simulates intra-reservoir migration between two compartments. We illustrate this method to detect fluid leakage in three different reservoirs with varying levels of geological and structural complexity. The proposed leakage detection method has three novelties: i) requires only readily-available data (injection and production rates), ii) accounts for fluid compressibility and boundary effects, and iii) in addition to

  14. Elevation profile influence at key contractual performance parameters for LDS (Leak Detection Systems) based on compensated volume balance

    Energy Technology Data Exchange (ETDEWEB)

    Liebenberg, Lieb [TRANSNET Pipeline, Durban (South Africa); Bueno, David; Passos, Rafaela [KANOPUS Consulting, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper describes and discusses procedures and correlations to estimate performance parameters for Leak Detection Systems based on Compensation Volume Balance, at the portions not usually covered by international standards (like, API RP 1130). These parameters include: minimum acceptable leakage to be detected, under steady state conditions, based on flow measurement uncertainty, observed for both pipeline head and tail; an actual flow rate uncertainty against the one informed by the flow meter manufacturer documentation; the reference flow rate for steady state conditions; and the sensitivity one may expect for the system against a given probability of false alarms (i.e., the ways to correlate reliability, the main performance parameter as per API RP 1130 and sensitivity, the second one). A question usually not considered is: how the elevation profile may affect some of these parameters. That is the second main objective addressed herein, with actual examples employed in a South African multi product pipeline. (author)

  15. Rewarded remembering: dissociations between self-rated motivation and memory performance.

    Science.gov (United States)

    Ngaosuvan, Leonard; Mäntylä, Timo

    2005-08-01

    People often claim that they perform better in memory performance tasks when they are more motivated. However, past research has shown minimal effects of motivation on memory performance when factors contributing to item-specific biases during encoding and retrieval are taken into account. The purpose of the present study was to examine the generality of this apparent dissociation by using more sensitive measures of experienced motivation and memory performance. Extrinsic motivation was manipulated through competition instructions, and subjective ratings of intrinsic and extrinsic motivation were obtained before and after study instructions. Participants studied a series of words, and memory performance was assessed by content recall (Experiment 1) and source recall (Experiment 2). Both experiments showed dissociation between subjective ratings of extrinsic motivation and actual memory performance, so that competition increased self-rated extrinsic motivation but had no effects on memory performance, including source recall. Inconsistent with most people's expectations, the findings suggest that extrinsic motivation has minimal effects on memory performance.

  16. Performance Analysis of Long-Reach Coherent Detection OFDM-PON Downstream Transmission Using m-QAM-Mapped OFDM Signal

    Science.gov (United States)

    Pandey, Gaurav; Goel, Aditya

    2017-12-01

    In this paper, orthogonal frequency division multiplexing (OFDM)-passive optical network (PON) downstream transmission is demonstrated over different lengths of fiber at remote node (RN) for different m-QAM (quadrature amplitude modulation)-mapped OFDM signal (m=4, 16, 32 and 64) transmission from the central office (CO) for different data rates (10, 20 30 and 40 Gbps) using coherent detection at the user end or optical network unit (ONU). Investigation is performed with different number of subcarriers (32, 64, 128, 512 and 1,024), back-to-back optical signal-to-noise ratio (OSNR) along with transmitted and received constellation diagrams for m-QAM-mapped coherent OFDM downstream transmission at different speeds over different transmission distances. Received optical power is calculated for different bit error rates (BERs) at different speeds using m-QAM-mapped coherent detection OFDM downstream transmission. No dispersion compensation is utilized in between the fiber span. Simulation results suggest the different lengths and data rates that can be used for different m-QAM-mapped coherent detection OFDM downstream transmission, and the proposed system may be implemented in next-generation high-speed PONs (NG-PONs).

  17. A Combined Syntactical and Statistical Approach for R Peak Detection in Real-Time Long-Term Heart Rate Variability Analysis

    Directory of Open Access Journals (Sweden)

    David Pang

    2018-06-01

    Full Text Available Long-term heart rate variability (HRV analysis is useful as a noninvasive technique for autonomic nervous system activity assessment. It provides a method for assessing many physiological and pathological factors that modulate the normal heartbeat. The performance of HRV analysis systems heavily depends on a reliable and accurate detection of the R peak of the QRS complex. Ectopic beats caused by misdetection or arrhythmic events can introduce bias into HRV results, resulting in significant problems in their interpretation. This study presents a novel method for long-term detection of normal R peaks (which represent the normal heartbeat in electrocardiographic signals, intended specifically for HRV analysis. The very low computational complexity of the proposed method, which combines and exploits the advantages of syntactical and statistical approaches, enables real-time applications. The approach was validated using the Massachusetts Institute of Technology–Beth Israel Hospital Normal Sinus Rhythm and the Fantasia database, and has a sensitivity, positive predictivity, detection error rate, and accuracy of 99.998, 99.999, 0.003, and 99.996%, respectively.

  18. The time course of cancer detection performance

    Science.gov (United States)

    Taylor-Phillips, Sian; Clarke, Aileen; Wallis, Matthew; Wheaton, Margot; Duncan, Alison; Gale, Alastair G.

    2011-03-01

    The purpose of this study was to measure how mammography readers' performance varies with time of day and time spent reading. This was investigated in screening practice and when reading an enriched case set. In screening practice records of time and date that each case was read, along with outcome (whether the woman was recalled for further tests, and biopsy results where performed) was extracted from records from one breast screening centre in UK (4 readers). Patterns of performance with time spent reading was also measured using an enriched test set (160 cases, 41% malignant, read three times by eight radiologists). Recall rates varied with time of day, with different patterns for each reader. Recall rates decreased as the reading session progressed both when reading the enriched test set and in screening practice. Further work is needed to expand this work to a greater number of breast screening centres, and to determine whether these patterns of performance over time can be used to optimize overall performance.

  19. Fiber optic sensor based on reflectivity configurations to detect heart rate

    Science.gov (United States)

    Yunianto, M.; Marzuki, A.; Riyatun, R.; Lestari, D.

    2016-11-01

    Research of optical fiber-based heart rate detection sensor has been conducted using the reflection configurationon the thorax motion modified. Optical fiber used in this research was Plastic Optical Fiber (POF) with a diameter of 0.5. Optical fiber system is made with two pieces of fiber, the first fiber is to serve as a transmitter transmitting light from the source to the reflector membrane, the second fiber serves as a receiver. One of the endsfrom the two fibersis pressed and positioned perpendicular of reflector membrane which is placed on the surface of the chest. The sensor works on the principle of intensity changes captured by the receiver fiber when the reflector membrane gets the vibe from the heart. The light source used is in the form of Light Emitting Diode (LED) and Light Dependent Resistor (LDR) as a light sensor. Variations are performed on the reflector membrane diameter. The light intensity received by the detector increases along with the increasing width of the reflector membrane diameter. The results show that this sensor can detect the harmonic peak at a frequency of 1.5 Hz; 7.5 Hz; 10.5 Hz; and 22.5 Hz in a healthy human heart with an average value of Beat Per Minute (BPM) by 78 times, a prototype sensor that is made can work and function properly.

  20. Comparison of detectable bleeding rates of radiopharmaceuticals for localization of gastrointestinal bleeding in sheep using a closed system

    International Nuclear Information System (INIS)

    Owunwanne, A.; Sadek, S.; Yacoub, T.; Awdeh, M.; Abdel-Dayem, H.M.; Al-Wafai, I.; Vallgren, S.

    1989-01-01

    The closed experimental animal model system was used to compare the detectable gastrointestinal (GI) bleeding rates of 99m Tc-DTPA, 99m Tc-RBCs and 99m Tc tin colloid in sheep. The three radiopharmaceuticals were used to detect the upper GI bleeding sites at rates of 0.57 and 0.25 ml/min. At the lower bleeding rate of 0.1 ml/min, both 99m Tc-DTPA and 99m Tc-RBCs were successful in detecting the bleeding site. At the lowest rate of 0.07 ml/min only 99m Tc-DTPA was successful in detecting the bleeding site. The results indicate that 99m Tc-DTPA is the most useful 99m Tc radiopharmaceutical for detecting the upper GI bleeding site at the slowest bleeding rate studied. (orig.) [de

  1. Using intraindividual variability to detect malingering in cognitive performance.

    Science.gov (United States)

    Strauss, E; Hultsch, D F; Hunter, M; Slick, D J; Patry, B; Levy-Bencheton, J

    1999-11-01

    The utility of measures for detecting malingering was evaluated using a simulation design in which half the participants were encouraged to do their best and half were asked to feign head injury. Particular attention was focused on the utility of repeated assessment (intraindividual variability) in discriminating the groups. Participants were tested on three occasions on measures commonly used to detect malingering including a specific symptom validity test (SVT). The results indicated that multiple measures of malingering obtained in single assessment (occasion one) discriminated the groups effectively. In addition, however, intraindividual variability in performance, particularly of indicators from the SVT, provided unique information beyond level of performance. The results suggest that response inconsistency across testing sessions may be a clinically useful measure for the detection of malingering.

  2. Analysis of microdialysate monoamines, including noradrenaline, dopamine and serotonin, using capillary ultra-high performance liquid chromatography and electrochemical detection.

    Science.gov (United States)

    Ferry, Barbara; Gifu, Elena-Patricia; Sandu, Ioana; Denoroy, Luc; Parrot, Sandrine

    2014-03-01

    Electrochemical methods are very often used to detect catecholamine and indolamine neurotransmitters separated by conventional reverse-phase high performance liquid chromatography (HPLC). The present paper presents the development of a chromatographic method to detect monoamines present in low-volume brain dialysis samples using a capillary column filled with sub-2μm particles. Several parameters (repeatability, linearity, accuracy, limit of detection) for this new ultrahigh performance liquid chromatography (UHPLC) method with electrochemical detection were examined after optimization of the analytical conditions. Noradrenaline, adrenaline, serotonin, dopamine and its metabolite 3-methoxytyramine were separated in 1μL of injected sample volume; they were detected above concentrations of 0.5-1nmol/L, with 2.1-9.5% accuracy and intra-assay repeatability equal to or less than 6%. The final method was applied to very low volume dialysates from rat brain containing monoamine traces. The study demonstrates that capillary UHPLC with electrochemical detection is suitable for monitoring dialysate monoamines collected at high sampling rate. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Standalone computer-aided detection compared to radiologists' performance for the detection of mammographic masses

    International Nuclear Information System (INIS)

    Hupse, Rianne; Samulski, Maurice; Imhof-Tas, Mechli W.; Karssemeijer, Nico; Lobbes, Marc; Boetes, Carla; Heeten, Ard den; Beijerinck, David; Pijnappel, Ruud

    2013-01-01

    We developed a computer-aided detection (CAD) system aimed at decision support for detection of malignant masses and architectural distortions in mammograms. The effect of this system on radiologists' performance depends strongly on its standalone performance. The purpose of this study was to compare the standalone performance of this CAD system to that of radiologists. In a retrospective study, nine certified screening radiologists and three residents read 200 digital screening mammograms without the use of CAD. Performances of the individual readers and of CAD were computed as the true-positive fraction (TPF) at a false-positive fraction of 0.05 and 0.2. Differences were analysed using an independent one-sample t-test. At a false-positive fraction of 0.05, the performance of CAD (TPF = 0.487) was similar to that of the certified screening radiologists (TPF = 0.518, P = 0.17). At a false-positive fraction of 0.2, CAD performance (TPF = 0.620) was significantly lower than the radiologist performance (TPF = 0.736, P <0.001). Compared to the residents, CAD performance was similar for all false-positive fractions. The sensitivity of CAD at a high specificity was comparable to that of human readers. These results show potential for CAD to be used as an independent reader in breast cancer screening. (orig.)

  4. The effect of changing from one to two views at incident (subsequent) screens in the NHS breast screening programme in England: impact on cancer detection and recall rates

    International Nuclear Information System (INIS)

    Blanks, R.G.; Bennett, R.L.; Patnick, J.; Cush, S.; Davison, C.; Moss, S.M.

    2005-01-01

    AIM: To assess the effect on cancer detection and recall rates of changing from one to two views for incident (subsequent) screens. METHODS: Controlled, comparative, observational study of programmes in NHS breast screening programme in England. Subjects: women aged 50-64 years were screened by the NHSBSP between 1 April 2001 and 31 March 2003. RESULTS: The effect of changing to two-view mammography was a 20% increase in overall incident screen cancer detection rate, with the biggest effect seen for small (<15 mm) invasive cancers. This increased detection rate was achieved with an 11% drop-in recall rate. CONCLUSION: The introduction of two-view mammography for incident screens has resulted in considerable improvements in overall NHS breast screening performance

  5. Detection of Operator Performance Breakdown as an Automation Triggering Mechanism

    Science.gov (United States)

    Yoo, Hyo-Sang; Lee, Paul U.; Landry, Steven J.

    2015-01-01

    Performance breakdown (PB) has been anecdotally described as a state where the human operator "loses control of context" and "cannot maintain required task performance." Preventing such a decline in performance is critical to assure the safety and reliability of human-integrated systems, and therefore PB could be useful as a point at which automation can be applied to support human performance. However, PB has never been scientifically defined or empirically demonstrated. Moreover, there is no validated objective way of detecting such a state or the transition to that state. The purpose of this work is: 1) to empirically demonstrate a PB state, and 2) to develop an objective way of detecting such a state. This paper defines PB and proposes an objective method for its detection. A human-in-the-loop study was conducted: 1) to demonstrate PB by increasing workload until the subject reported being in a state of PB, and 2) to identify possible parameters of a detection method for objectively identifying the subjectively-reported PB point, and 3) to determine if the parameters are idiosyncratic to an individual/context or are more generally applicable. In the experiment, fifteen participants were asked to manage three concurrent tasks (one primary and two secondary) for 18 minutes. The difficulty of the primary task was manipulated over time to induce PB while the difficulty of the secondary tasks remained static. The participants' task performance data was collected. Three hypotheses were constructed: 1) increasing workload will induce subjectively-identified PB, 2) there exists criteria that identifies the threshold parameters that best matches the subjectively-identified PB point, and 3) the criteria for choosing the threshold parameters is consistent across individuals. The results show that increasing workload can induce subjectively-identified PB, although it might not be generalizable-only 12 out of 15 participants declared PB. The PB detection method based on

  6. Device to detect the presence of a pure signal in a discrete noisy signal measured at an average rate of constant noise with a probability of false detection lower than one predeterminated

    International Nuclear Information System (INIS)

    Poussier, E.; Rambaut, M.

    1986-01-01

    Detection consists of a measurement of a counting rate. A probability of wrong detection is associated with this counting rate and with an average estimated rate of noise. Detection consists also in comparing the wrong detection probability to a predeterminated rate of wrong detection. The comparison can use tabulated values. Application is made to corpuscule radiation detection [fr

  7. Comparison of detectable bleeding rates of radiopharmaceuticals for localization of gastrointestinal bleeding in sheep using a closed system

    Energy Technology Data Exchange (ETDEWEB)

    Owunwanne, A.; Sadek, S.; Yacoub, T.; Awdeh, M.; Abdel-Dayem, H.M. (Kuwait Univ. (Kuwait). Dept. of Nuclear Medicine); Al-Wafai, I.; Vallgren, S. (Kuwait Univ. (Kuwait). Dept. of Surgery)

    1989-06-01

    The closed experimental animal model system was used to compare the detectable gastrointestinal (GI) bleeding rates of {sup 99m}Tc-DTPA, {sup 99m}Tc-RBCs and {sup 99m}Tc tin colloid in sheep. The three radiopharmaceuticals were used to detect the upper GI bleeding sites at rates of 0.57 and 0.25 ml/min. At the lower bleeding rate of 0.1 ml/min, both {sup 99m}Tc-DTPA and {sup 99m}Tc-RBCs were successful in detecting the bleeding site. At the lowest rate of 0.07 ml/min only {sup 99m}Tc-DTPA was successful in detecting the bleeding site. The results indicate that {sup 99m}Tc-DTPA is the most useful {sup 99m}Tc radiopharmaceutical for detecting the upper GI bleeding site at the slowest bleeding rate studied. (orig.).

  8. Diagnostic performance of digital breast tomosynthesis with a wide scan angle compared to full-field digital mammography for the detection and characterization of microcalcifications

    International Nuclear Information System (INIS)

    Clauser, Paola; Nagl, Georg; Helbich, Thomas H.; Pinker-Domenig, Katja; Weber, Michael; Kapetas, Panagiotis; Bernathova, Maria; Baltzer, Pascal A.T.

    2016-01-01

    Highlights: • Wide scan-angle DBT alone shows a high detection rate for microcalcifications. • DBT and FFDM can characterize microcalcifications at a comparable level. • Characterization is influenced by reader and by lesion type (benign vs malignant). • DBT might be used as a stand-alone technique for the assessment of microcalcifications. - Abstract: Objectives: To assess the diagnostic performance of digital breast tomosynthesis (DBT), with a wide scan-angle, compared to full-field digital mammography (FFDM), for the detection and characterization of microcalcifications. Methods: IRB approval was obtained for this retrospective study. We selected 150 FFDM and DBT (50 benign and 50 malignant histologically verified microcalcifications, 50 cases classified as BI-RADS 1). Four radiologists evaluated, in separate sessions and blinded to patients’ history and histology, the presence of microcalcifications. Cases with microcalcifications were assessed for visibility, characteristics, and grade of suspicion using BI-RADS categories. Detection rate and diagnostic performance were calculated. Visibility, lesions’ characteristics and reading time were analysed. Results: Detection rate and visibility were good for both FFDM and DBT, without intra-reader differences (P = 0.510). Inter-reader differences were detected (P < 0.018). Only two lesions were not detected by any reader on either FFDM or DBT. Diagnostic performance with DBT was as good as that of FFDM, but a significant inter-reader difference was found (P = 0.041). High inter-reader variability in the use of the descriptors was found. Reading time for DBT was almost twice that for FFDM (44 and 25 s, respectively). Conclusion: Wide scan-angle DBT enabled the detection and characterization of microcalcifications with no significant differences from FFDM. Inter-reader variability was seen.

  9. Diagnostic performance of digital breast tomosynthesis with a wide scan angle compared to full-field digital mammography for the detection and characterization of microcalcifications

    Energy Technology Data Exchange (ETDEWEB)

    Clauser, Paola, E-mail: paola.clauser@meduniwien.ac.at [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Nagl, Georg [Department for Radiology and Interventional Radiology, Landesklinikum Horn, Spitalgasse 10, 3580 Horn (Austria); Helbich, Thomas H., E-mail: thomas.helbich@meduniwien.ac.at [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Pinker-Domenig, Katja [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Weber, Michael [Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Kapetas, Panagiotis; Bernathova, Maria; Baltzer, Pascal A.T. [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria)

    2016-12-15

    Highlights: • Wide scan-angle DBT alone shows a high detection rate for microcalcifications. • DBT and FFDM can characterize microcalcifications at a comparable level. • Characterization is influenced by reader and by lesion type (benign vs malignant). • DBT might be used as a stand-alone technique for the assessment of microcalcifications. - Abstract: Objectives: To assess the diagnostic performance of digital breast tomosynthesis (DBT), with a wide scan-angle, compared to full-field digital mammography (FFDM), for the detection and characterization of microcalcifications. Methods: IRB approval was obtained for this retrospective study. We selected 150 FFDM and DBT (50 benign and 50 malignant histologically verified microcalcifications, 50 cases classified as BI-RADS 1). Four radiologists evaluated, in separate sessions and blinded to patients’ history and histology, the presence of microcalcifications. Cases with microcalcifications were assessed for visibility, characteristics, and grade of suspicion using BI-RADS categories. Detection rate and diagnostic performance were calculated. Visibility, lesions’ characteristics and reading time were analysed. Results: Detection rate and visibility were good for both FFDM and DBT, without intra-reader differences (P = 0.510). Inter-reader differences were detected (P < 0.018). Only two lesions were not detected by any reader on either FFDM or DBT. Diagnostic performance with DBT was as good as that of FFDM, but a significant inter-reader difference was found (P = 0.041). High inter-reader variability in the use of the descriptors was found. Reading time for DBT was almost twice that for FFDM (44 and 25 s, respectively). Conclusion: Wide scan-angle DBT enabled the detection and characterization of microcalcifications with no significant differences from FFDM. Inter-reader variability was seen.

  10. Neutron detection performance of silicon carbide and diamond detectors with incomplete charge collection properties

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, M., E-mail: michael.hodgson@becq.co.uk [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Lohstroh, A.; Sellin, P. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Thomas, D. [NPL, Teddington TW11 0LW (United Kingdom)

    2017-03-01

    The benefits of neutron detection and spectroscopy with carbon based, wide band gap, semiconductor detectors have previously been discussed within the literature. However, at the time of writing there are still limitations with these detectors related to availability, cost, size and perceived quality. This study demonstrates that lower quality materials—indicated by lower charge collection efficiency (CCE), poor resolution and polarisation effect—available at wafer scale and lower cost, can fulfil requirements for fast neutron detection and spectroscopy for fluxes over several orders of magnitude, where only coarse energy discrimination is required. In this study, a single crystal diamond detector (D-SC, with 100% CCE), a polycrystalline diamond (D-PC, with ≈4% CCE) and semi-insulating silicon carbide (SiC-SI, with ≈35% CCE) have been compared for alpha and fast neutron performance. All detectors demonstrated alpha induced polarisation effects in the form of a change of both energy peak position and count rate with irradiation time. Despite these operational issues the ability to detect fast neutrons and distinguish neutron energies was observed. This performance was demonstrated over a wide dynamic range (500–40,000 neutrons/s), with neutron induced polarisation being demonstrated in D-PC and SiC-SI at high fluxes.

  11. Impact of a shift in nuchal translucency measurements on the detection rate of first-trimester Down syndrome screening: A population-based study.

    Science.gov (United States)

    Fries, Nicolas; Salomon, Laurent J; Muller, Françoise; Dreux, Sophie; Houfflin-Debarge, Véronique; Coquel, Philippe; Kleinfinger, Pascale; Dommergues, Marc

    2018-01-01

    To assess the distribution of nuchal translucency (NT) measurements following a national policy without credentialing and its impact on first-trimester Down syndrome screening (DSS) detection rate. All first-trimester DSS data recorded in France (2010-2014) were collected by the laboratories in charge via an Internet database (https://www.bionuqual.org/echo.php). There was no minimal requirement for image quality to allow sonographers to enter the screening process. A subgroup of DSS with complete DS follow-up corresponded to 1614 sonographers. Based on the distribution of maternal age, DS detection rate was calculated and split as a function of the distribution of NT multiple of the median (MoM). Four thousand nine hundred forty-three sonographers performed 2,337,372 NT measurements. Median NT expressed in MoM was 0.83. Screenings with complete follow-up consisted of 197,417 screenings, in which DSS detection rates were respectively 70.4%, 70.9%, 79.4%, 87.7%, and 79.5% for the following median NT MoM ranges: 0.99 (trend χ = 12.21; P = .0158). In France, following a policy of quality assessment without standardized credentialing, the distribution of NT measurements did not fit the expected distribution. Down syndrome detection rate was 10% lower in screenings by sonographers with a median NT < 0.80 MoM. © 2017 John Wiley & Sons, Ltd.

  12. Auditory detection of an increment in the rate of a random process

    International Nuclear Information System (INIS)

    Brown, W.S.; Emmerich, D.S.

    1994-01-01

    Recent experiments have presented listeners with complex tonal stimuli consisting of components with values (i.e., intensities or frequencies) randomly sampled from probability distributions [e.g., R. A. Lutfi, J. Acoust. Soc. Am. 86, 934--944 (1989)]. In the present experiment, brief tones were presented at intervals corresponding to the intensity of a random process. Specifically, the intervals between tones were randomly selected from exponential probability functions. Listeners were asked to decide whether tones presented during a defined observation interval represented a ''noise'' process alone or the ''noise'' with a ''signal'' process added to it. The number of tones occurring in any observation interval is a Poisson variable; receiver operating characteristics (ROCs) arising from Poisson processes have been considered by Egan [Signal Detection Theory and ROC Analysis (Academic, New York, 1975)]. Several sets of noise and signal intensities and observation interval durations were selected which were expected to yield equivalent performance. Rating ROCs were generated based on subjects' responses in a single-interval, yes--no task. The performance levels achieved by listeners and the effects of intensity and duration are compared to those predicted for an ideal observer

  13. Rate adaptive multilevel coded modulation with high coding gain in intensity modulation direct detection optical communication

    Science.gov (United States)

    Xiao, Fei; Liu, Bo; Zhang, Lijia; Xin, Xiangjun; Zhang, Qi; Tian, Qinghua; Tian, Feng; Wang, Yongjun; Rao, Lan; Ullah, Rahat; Zhao, Feng; Li, Deng'ao

    2018-02-01

    A rate-adaptive multilevel coded modulation (RA-MLC) scheme based on fixed code length and a corresponding decoding scheme is proposed. RA-MLC scheme combines the multilevel coded and modulation technology with the binary linear block code at the transmitter. Bits division, coding, optional interleaving, and modulation are carried out by the preset rule, then transmitted through standard single mode fiber span equal to 100 km. The receiver improves the accuracy of decoding by means of soft information passing through different layers, which enhances the performance. Simulations are carried out in an intensity modulation-direct detection optical communication system using MATLAB®. Results show that the RA-MLC scheme can achieve bit error rate of 1E-5 when optical signal-to-noise ratio is 20.7 dB. It also reduced the number of decoders by 72% and realized 22 rate adaptation without significantly increasing the computing time. The coding gain is increased by 7.3 dB at BER=1E-3.

  14. Rating the Effectiveness of Fishery Closures With Visible Infrared Imaging Radiometer Suite Boat Detection Data

    Directory of Open Access Journals (Sweden)

    Christopher D. Elvidge

    2018-04-01

    Full Text Available Fishery closures are widely used to promote the sustainability of fish stocks. Fishery agencies typically have very little data relevant to planning closure enforcement actions and evaluating the effectiveness of closures, due in part to the vast expanse and remote nature of many closures. In some cases the effectiveness of closures can be evaluated using data from GPS based beacons, such as Automatic Identification System (AIS or Vessel Monitoring Systems (VMS installed on fishing boats. In fisheries where few boats are equipped with AIS or VMS, the rating of closures relies on other data sources capable of detecting or inferring fishing activity. One such source comes from low light imaging data collected by the NASA/NOAA Visible Infrared Imaging Radiometer Suite (VIIRS, which can detect fishing boats using lights to attract catch. This is a widely used practice in Asia and several other regions. NOAA has developed an automatic system for reporting the locations of VIIRS boat detections with a nominal 4 h temporal latency. VIIRS boat detection alerts are running for more than 900 fishery closures in the Philippines, with email and SMS transmission modes. These alerts are being actively used in the Philippines to plan enforcement actions and there is a growing list of apprehensions that occurred based on tip-offs from VIIRS. The VIIRS boat detection archive extends back to April 2012. A VIIRS closure index (VCI has been developed to rate the effectiveness of closures on monthly increments in terms of a percentage. The VCI analysis was performed on three types of closures: an ad hoc fishery closure associated with a toxic industrial discharge, a seasonal fishery closure and a permanent closure in restricted coastal waters. The VCI results indicate that it is possible to rank the effectiveness of different closure, year-to-year differences in compliance levels, and to identify closure encroachments which may warrant additional enforcement effort.

  15. Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

    Science.gov (United States)

    Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

    2017-03-01

    Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Conflict Detection Performance Analysis for Function Allocation Using Time-Shifted Recorded Traffic Data

    Science.gov (United States)

    Guerreiro, Nelson M.; Butler, Ricky W.; Maddalon, Jeffrey M.; Hagen, George E.; Lewis, Timothy A.

    2015-01-01

    The performance of the conflict detection function in a separation assurance system is dependent on the content and quality of the data available to perform that function. Specifically, data quality and data content available to the conflict detection function have a direct impact on the accuracy of the prediction of an aircraft's future state or trajectory, which, in turn, impacts the ability to successfully anticipate potential losses of separation (detect future conflicts). Consequently, other separation assurance functions that rely on the conflict detection function - namely, conflict resolution - are prone to negative performance impacts. The many possible allocations and implementations of the conflict detection function between centralized and distributed systems drive the need to understand the key relationships that impact conflict detection performance, with respect to differences in data available. This paper presents the preliminary results of an analysis technique developed to investigate the impacts of data quality and data content on conflict detection performance. Flight track data recorded from a day of the National Airspace System is time-shifted to create conflicts not present in the un-shifted data. A methodology is used to smooth and filter the recorded data to eliminate sensor fusion noise, data drop-outs and other anomalies in the data. The metrics used to characterize conflict detection performance are presented and a set of preliminary results is discussed.

  17. The performance of spatially offset Raman spectroscopy for liquid explosive detection

    Science.gov (United States)

    Loeffen, Paul W.; Maskall, Guy; Bonthron, Stuart; Bloomfield, Matthew; Tombling, Craig; Matousek, Pavel

    2016-10-01

    Aviation security requirements adopted in 2014 require liquids to be screened at most airports throughout Europe, North America and Australia. Cobalt's unique Spatially Offset Raman Spectroscopy (SORS™) technology has proven extremely effective at screening liquids, aerosols and gels (LAGS) with extremely low false alarm rates. SORS is compatible with a wide range of containers, including coloured, opaque or clear plastics, glass and paper, as well as duty-free bottles in STEBs (secure tamper-evident bags). Our award-winning Insight range has been specially developed for table-top screening at security checkpoints. Insight systems use our patented SORS technology for rapid and accurate chemical analysis of substances in unopened non-metallic containers. Insight100M™ and the latest member of the range - Insight200M™ - also screen metallic containers. Our unique systems screen liquids, aerosols and gels with the highest detection capability and lowest false alarm rates of any ECAC-approved scanner, with several hundred units already in use at airports including eight of the top ten European hubs. This paper presents an analysis of real performance data for these systems.

  18. Performance evaluation of the Aptima HSV-1 and 2 assay for the detection of HSV in cutaneous and mucocutaneous lesion specimens.

    Science.gov (United States)

    Sam, Soya S; Caliendo, Angela M; Ingersoll, Jessica; Abdul-Ali, Deborah; Kraft, Colleen S

    Timely and precise laboratory diagnosis of Herpes simplex viruses (HSV) is required to guide clinical management. The study evaluated limit of detection (LOD) and performance characteristics of the Aptima HSV 1 & 2 assay in comparison to four assays. The multi-center study compared qualitative detection of HSV-1 and 2 by the Aptima HSV-1 and 2 assay (Hologic) to ELVIS culture, Lyra Direct (Quidel), AmpliVue (Quidel) and a laboratory developed test (LDT). LOD was performed using VTM and STM diluted viral concentrations and clinical performance was evaluated using 505 swab specimens. The Aptima LOD studies performed showed a lower detection limit for STM specimens as 1450 copies/mL and 430 copies/mL for HSV1 and HSV-2 respectively; the LOD for VTM specimens was 9370 copies/mL and 8045 copies/mL for HSV-1 and HSV-2 respectively. When the assays were analyzed based on the positive consensus result established the Aptima had 95% of percent positive agreement (PPA) and 100% negative percent agreement (NPA) for the HSV-1. For the HSV-2, the PPA and NPA for Aptima were 96% and 100% respectively. AmpliVue had 1.8% invalid rate, while Lyra had no invalid results but an inhibition rate of 0.8%. Aptima and LDT did not have any invalid or inhibited results. The results indicate that the Aptima HSV-1 & 2 assay is sensitive and the performance characteristics of the Aptima assay is comparable to the assays analyzed for the detection and differentiation of HSV-1 and 2 from cutaneous and mucocutaneous lesions. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Market response to the public display of energy performance rating at property sales

    International Nuclear Information System (INIS)

    Jensen, Ole Michael; Hansen, Anders Rhiger; Kragh, Jesper

    2016-01-01

    Energy labels have generally received positive response from consumers and have moved the market for white goods and cars in the direction of more energy-efficient products. On the real estate market, it was expected that an energy label, rating the energy performance of a property based on a national energy performance certificate (EPC) might receive similar response. However, in Denmark no response to the energy performance rating was observed for 15 years. This was a surprise considering that Denmark was the first country to implement an A to G rating of the energy performance of buildings. A statistical examination of data on property sales prices and energy performance ratings was carried out. All relevant property transaction data from 2007 till 2012 were examined and they showed that energy performance ratings had an impact on property sales prices. However, before June 2010, the impact was modest, whereas after June 2010 the impact of energy performance ratings on property sales prices increased significantly as a result of an EU requirement to display the energy performance rating in connection with property sales. On this background, it was concluded that a public display of the energy performance rating is fundamental for market response. - Highlights: •Energy performance ratings of buildings have an impact on property sales prices. •A statistical examination shows that since 2010 sales prices reflect energy performance. •Mandatory display of the rating prescribed by EU Directive was decisive. •The positive market response will be an incentive for energy upgrading of the property.

  20. Performance improvement of haptic collision detection using subdivision surface and sphere clustering.

    Directory of Open Access Journals (Sweden)

    A Ram Choi

    Full Text Available Haptics applications such as surgery simulations require collision detections that are more precise than others. An efficient collision detection method based on the clustering of bounding spheres was proposed in our prior study. This paper analyzes and compares the applied effects of the five most common subdivision surface methods on some 3D models for haptic collision detection. The five methods are Butterfly, Catmull-Clark, Mid-point, Loop, and LS3 (Least Squares Subdivision Surface. After performing a number of experiments, we have concluded that LS3 method is the most appropriate for haptic simulations. The more we applied surface subdivision, the more the collision detection results became precise. However, it is observed that the performance becomes better until a certain threshold and degrades afterward. In order to reduce the performance degradation, we adopted our prior work, which was the fast and precise collision detection method based on adaptive clustering. As a result, we obtained a notable improvement of the speed of collision detection.

  1. On the performance of pre-microRNA detection algorithms

    DEFF Research Database (Denmark)

    Saçar Demirci, Müşerref Duygu; Baumbach, Jan; Allmer, Jens

    2017-01-01

    assess 13 ab initio pre-miRNA detection approaches using all relevant, published, and novel data sets while judging algorithm performance based on ten intrinsic performance measures. We present an extensible framework, izMiR, which allows for the unbiased comparison of existing algorithms, adding new...

  2. Pre-performance Physiological State: Heart Rate Variability as a Predictor of Shooting Performance.

    Science.gov (United States)

    Ortega, E; Wang, C J K

    2018-03-01

    Heart rate variability (HRV) is commonly used in sport science for monitoring the physiology of athletes but not as an indicator of physiological state from a psychological perspective. Since HRV is established to be an indicator of emotional responding, it could be an objective means of quantifying an athlete's subjective physiological state before competition. A total of 61 sport shooters participated in this study, of which 21 were novice shooters, 19 were intermediate shooters, and 21 were advanced level shooters. HRV, self-efficacy, and use of mental skills were assessed before they completed a standard shooting performance task of 40 shots, as in a competition qualifying round. The results showed that HRV was significantly positively correlated with self-efficacy and performance and was a significant predictor of shooting performance. In addition, advanced shooters were found to have significantly lower average heart rate before shooting and used more self-talk, relaxation, imagery, and automaticity compared to novice and intermediate shooters. HRV was found to be useful in identifying the physiological state of an athlete before competing, and as such, coaches and athletes can adopt practical strategies to improve the pre-performance physiological state as a means to optimize performance.

  3. Detection of Local Cancer Recurrence After Stereotactic Ablative Radiation Therapy for Lung Cancer: Physician Performance Versus Radiomic Assessment

    International Nuclear Information System (INIS)

    Mattonen, Sarah A.; Palma, David A.; Johnson, Carol; Louie, Alexander V.; Landis, Mark; Rodrigues, George; Chan, Ian; Etemad-Rezai, Roya; Yeung, Timothy P.C.; Senan, Suresh; Ward, Aaron D.

    2016-01-01

    Purpose: Stereotactic ablative radiation therapy (SABR) is a guideline-specified treatment option for early-stage lung cancer. However, significant posttreatment fibrosis can occur and obfuscate the detection of local recurrence. The goal of this study was to assess physician ability to detect timely local recurrence and to compare physician performance with a radiomics tool. Methods and Materials: Posttreatment computed tomography (CT) scans (n=182) from 45 patients treated with SABR (15 with local recurrence matched to 30 with no local recurrence) were used to measure physician and radiomic performance in assessing response. Scans were individually scored by 3 thoracic radiation oncologists and 3 thoracic radiologists, all of whom were blinded to clinical outcomes. Radiomic features were extracted from the same images. Performances of the physician assessors and the radiomics signature were compared. Results: When taking into account all CT scans during the whole follow-up period, median sensitivity for physician assessment of local recurrence was 83% (range, 67%-100%), and specificity was 75% (range, 67%-87%), with only moderate interobserver agreement (κ = 0.54) and a median time to detection of recurrence of 15.5 months. When determining the early prediction of recurrence within <6 months after SABR, physicians assessed the majority of images as benign injury/no recurrence, with a mean error of 35%, false positive rate (FPR) of 1%, and false negative rate (FNR) of 99%. At the same time point, a radiomic signature consisting of 5 image-appearance features demonstrated excellent discrimination, with an area under the receiver operating characteristic curve of 0.85, classification error of 24%, FPR of 24%, and FNR of 23%. Conclusions: These results suggest that radiomics can detect early changes associated with local recurrence that are not typically considered by physicians. This decision support system could potentially allow for early salvage therapy of

  4. Detection of Local Cancer Recurrence After Stereotactic Ablative Radiation Therapy for Lung Cancer: Physician Performance Versus Radiomic Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mattonen, Sarah A. [Department of Medical Biophysics, The University of Western Ontario, London, Ontario (Canada); Baines Imaging Research Laboratory, London Regional Cancer Program, London, Ontario (Canada); Palma, David A., E-mail: david.palma@lhsc.on.ca [Department of Medical Biophysics, The University of Western Ontario, London, Ontario (Canada); Baines Imaging Research Laboratory, London Regional Cancer Program, London, Ontario (Canada); Department of Oncology, The University of Western Ontario, London, Ontario (Canada); Johnson, Carol [Baines Imaging Research Laboratory, London Regional Cancer Program, London, Ontario (Canada); Louie, Alexander V. [Department of Oncology, The University of Western Ontario, London, Ontario (Canada); Landis, Mark [Department of Diagnostic Radiology, London Health Sciences Centre, London, Ontario (Canada); Rodrigues, George [Department of Oncology, The University of Western Ontario, London, Ontario (Canada); Chan, Ian; Etemad-Rezai, Roya [Department of Diagnostic Radiology, London Health Sciences Centre, London, Ontario (Canada); Yeung, Timothy P.C. [Department of Medical Biophysics, The University of Western Ontario, London, Ontario (Canada); Baines Imaging Research Laboratory, London Regional Cancer Program, London, Ontario (Canada); Senan, Suresh [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands); Ward, Aaron D. [Department of Medical Biophysics, The University of Western Ontario, London, Ontario (Canada); Baines Imaging Research Laboratory, London Regional Cancer Program, London, Ontario (Canada); Department of Oncology, The University of Western Ontario, London, Ontario (Canada)

    2016-04-01

    Purpose: Stereotactic ablative radiation therapy (SABR) is a guideline-specified treatment option for early-stage lung cancer. However, significant posttreatment fibrosis can occur and obfuscate the detection of local recurrence. The goal of this study was to assess physician ability to detect timely local recurrence and to compare physician performance with a radiomics tool. Methods and Materials: Posttreatment computed tomography (CT) scans (n=182) from 45 patients treated with SABR (15 with local recurrence matched to 30 with no local recurrence) were used to measure physician and radiomic performance in assessing response. Scans were individually scored by 3 thoracic radiation oncologists and 3 thoracic radiologists, all of whom were blinded to clinical outcomes. Radiomic features were extracted from the same images. Performances of the physician assessors and the radiomics signature were compared. Results: When taking into account all CT scans during the whole follow-up period, median sensitivity for physician assessment of local recurrence was 83% (range, 67%-100%), and specificity was 75% (range, 67%-87%), with only moderate interobserver agreement (κ = 0.54) and a median time to detection of recurrence of 15.5 months. When determining the early prediction of recurrence within <6 months after SABR, physicians assessed the majority of images as benign injury/no recurrence, with a mean error of 35%, false positive rate (FPR) of 1%, and false negative rate (FNR) of 99%. At the same time point, a radiomic signature consisting of 5 image-appearance features demonstrated excellent discrimination, with an area under the receiver operating characteristic curve of 0.85, classification error of 24%, FPR of 24%, and FNR of 23%. Conclusions: These results suggest that radiomics can detect early changes associated with local recurrence that are not typically considered by physicians. This decision support system could potentially allow for early salvage therapy of

  5. Two K versus 4 K storage phosphor chest radiography: detection performance and image quality

    International Nuclear Information System (INIS)

    Koelblinger, Claus; Weber, Michael; Sailer, Johannes; Cartes-Zumelzu, Fabiola; Prokop, Mathias; Schaefer-Prokop, Cornelia

    2007-01-01

    The purpose of this study was to evaluate the effect of matrix size (4-K versus 2-K) in digital storage phosphor chest radiographs on image quality and on the detection of CT-proven thoracic abnormalities. In 85 patients who underwent a CT of the thorax, we obtained two additional posteroanterior storage phosphor chest radiographs, one with a matrix size of 3,520 x 4,280 (=4-K) and the other with a matrix size of 1,760 x 2,140 (=2-K). Acquisition, processing and presentation parameters were identical for all radiographs. Two radiologists evaluated the presence of mediastinal, pleural, and pulmonary abnormalities on hard copies of the radiographs, applying ROC analysis. In addition, four radiologists were asked to subjectively rank differences in image quality and to assess the demarcation of anatomic landmarks comparing the images in a blinded side-by-side manner. These data were analyzed using a two-sided binomial test with a significance level of P<0.05. Both tests, the ROC analysis of the detection performance and the binomial test of the subjective quality ratings, did not reveal significant differences between the two matrix sizes. Compared to 2-K radiographs, 4-K storage phosphor chest radiographs do not provide superior detection performance or image quality when evaluated in identical hard copy formats. (orig.)

  6. Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

    Science.gov (United States)

    Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

    2015-07-01

    Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

  7. Predicting work Performance through selection interview ratings and Psychological assessment

    Directory of Open Access Journals (Sweden)

    Liziwe Nzama

    2008-11-01

    Full Text Available The aim of the study was to establish whether selection interviews used in conjunction with psychological assessments of personality traits and cognitive functioning contribute to predicting work performance. The sample consisted of 102 managers who were appointed recently in a retail organisation. The independent variables were selection interview ratings obtained on the basis of structured competency-based interview schedules by interviewing panels, fve broad dimensions of personality defned by the Five Factor Model as measured by the 15 Factor Questionnaire (15FQ+, and cognitive processing variables (current level of work, potential level of work, and 12 processing competencies measured by the Cognitive Process Profle (CPP. Work performance was measured through annual performance ratings that focused on measurable outputs of performance objectives. Only two predictor variables correlated statistically signifcantly with the criterion variable, namely interview ratings (r = 0.31 and CPP Verbal Abstraction (r = 0.34. Following multiple regression, only these variables contributed signifcantly to predicting work performance, but only 17.8% of the variance of the criterion was accounted for.

  8. Minimum Symbol Error Rate Detection in Single-Input Multiple-Output Channels with Markov Noise

    DEFF Research Database (Denmark)

    Christensen, Lars P.B.

    2005-01-01

    Minimum symbol error rate detection in Single-Input Multiple- Output(SIMO) channels with Markov noise is presented. The special case of zero-mean Gauss-Markov noise is examined closer as it only requires knowledge of the second-order moments. In this special case, it is shown that optimal detection...

  9. Complexity rating of abnormal events and operator performance

    International Nuclear Information System (INIS)

    Oeivind Braarud, Per

    1998-01-01

    The complexity of the work situation during abnormal situations is a major topic in a discussion of safety aspects of Nuclear Power plants. An understanding of complexity and its impact on operator performance in abnormal situations is important. One way to enhance understanding is to look at the dimensions that constitute complexity for NPP operators, and how those dimensions can be measured. A further step is to study how dimensions of complexity of the event are related to performance of operators. One aspect of complexity is the operator 's subjective experience of given difficulties of the event. Another related aspect of complexity is subject matter experts ratings of the complexity of the event. A definition and a measure of this part of complexity are being investigated at the OECD Halden Reactor Project in Norway. This paper focus on the results from a study of simulated scenarios carried out in the Halden Man-Machine Laboratory, which is a full scope PWR simulator. Six crews of two licensed operators each performed in 16 scenarios (simulated events). Before the experiment subject matter experts rated the complexity of the scenarios, using a Complexity Profiling Questionnaire. The Complexity Profiling Questionnaire contains eight previously identified dimensions associated with complexity. After completing the scenarios the operators received a questionnaire containing 39 questions about perceived complexity. This questionnaire was used for development of a measure of subjective complexity. The results from the study indicated that Process experts' rating of scenario complexity, using the Complexity Profiling Questionnaire, were able to predict crew performance quite well. The results further indicated that a measure of subjective complexity could be developed that was related to crew performance. Subjective complexity was found to be related to subjective work load. (author)

  10. Human care system for heart-rate and human-movement trajectory in home and its application to detect mental disease

    Science.gov (United States)

    Hata, Yutaka; Kanazawa, Seigo; Endo, Maki; Tsuchiya, Naoki; Nakajima, Hiroshi

    2012-06-01

    This paper proposes a heart rate monitoring system for detecting autonomic nervous system by the heart rate variability using an air pressure sensor to diagnose mental disease. Moreover, we propose a human behavior monitoring system for detecting the human trajectory in home by an infrared camera. In day and night times, the human behavior monitoring system detects the human movement in home. The heart rate monitoring system detects the heart rate in bed in night time. The air pressure sensor consists of a rubber tube, cushion cover and pressure sensor, and it detects the heart rate by setting it to bed. It unconstraintly detects the RR-intervals; thereby the autonomic nervous system can be assessed. The autonomic nervous system analysis can examine the mental disease. While, the human behavior monitoring system obtains distance distribution image by an infrared camera. It classifies adult, child and the other object from distance distribution obtained by the camera, and records their trajectories. This behavior, i.e., trajectory in home, strongly corresponds to cognitive disorders. Thus, the total system can detect mental disease and cognitive disorders by uncontacted sensors to human body.

  11. Detection of argan oil adulteration with vegetable oils by high-performance liquid chromatography-evaporative light scattering detection.

    Science.gov (United States)

    Salghi, Rachid; Armbruster, Wolfgang; Schwack, Wolfgang

    2014-06-15

    Triacylglycerol profiles were selected as indicator of adulteration of argan oils to carry out a rapid screening of samples for the evaluation of authenticity. Triacylglycerols were separated by high-performance liquid chromatography-evaporative light scattering detection. Different peak area ratios were defined to sensitively detect adulteration of argan oil with vegetable oils such as sunflower, soy bean, and olive oil up to the level of 5%. Based on four reference argan oils, mean limits of detection and quantitation were calculated to approximately 0.4% and 1.3%, respectively. Additionally, 19 more argan oil reference samples were analysed by high-performance liquid chromatography-refractive index detection, resulting in highly comparative results. The overall strategy demonstrated a good applicability in practise, and hence a high potential to be transferred to routine laboratories. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Predicting detection performance with model observers: Fourier domain or spatial domain?

    Science.gov (United States)

    Chen, Baiyu; Yu, Lifeng; Leng, Shuai; Kofler, James; Favazza, Christopher; Vrieze, Thomas; McCollough, Cynthia

    2016-02-27

    The use of Fourier domain model observer is challenged by iterative reconstruction (IR), because IR algorithms are nonlinear and IR images have noise texture different from that of FBP. A modified Fourier domain model observer, which incorporates nonlinear noise and resolution properties, has been proposed for IR and needs to be validated with human detection performance. On the other hand, the spatial domain model observer is theoretically applicable to IR, but more computationally intensive than the Fourier domain method. The purpose of this study is to compare the modified Fourier domain model observer to the spatial domain model observer with both FBP and IR images, using human detection performance as the gold standard. A phantom with inserts of various low contrast levels and sizes was repeatedly scanned 100 times on a third-generation, dual-source CT scanner at 5 dose levels and reconstructed using FBP and IR algorithms. The human detection performance of the inserts was measured via a 2-alternative-forced-choice (2AFC) test. In addition, two model observer performances were calculated, including a Fourier domain non-prewhitening model observer and a spatial domain channelized Hotelling observer. The performance of these two mode observers was compared in terms of how well they correlated with human observer performance. Our results demonstrated that the spatial domain model observer correlated well with human observers across various dose levels, object contrast levels, and object sizes. The Fourier domain observer correlated well with human observers using FBP images, but overestimated the detection performance using IR images.

  13. MIMO scheme performance and detection in epsilon noise

    OpenAIRE

    Stepanov, Sander

    2006-01-01

    New approach for analysis and decoding MIMO signaling is developed for usual model of nongaussion noise consists of background and impulsive noise named epsilon - noise. It is shown that non-gaussion noise performance significantly worse than gaussion ones. Stimulation results strengthen out theory. Robust in statistical sense detection rule is suggested for such kind of noise features much best robust detector performance than detector designed for Gaussian noise in impulsive environment and...

  14. Detection of Driver Drowsiness Using Wavelet Analysis of Heart Rate Variability and a Support Vector Machine Classifier

    Directory of Open Access Journals (Sweden)

    Gang Li

    2013-12-01

    Full Text Available Driving while fatigued is just as dangerous as drunk driving and may result in car accidents. Heart rate variability (HRV analysis has been studied recently for the detection of driver drowsiness. However, the detection reliability has been lower than anticipated, because the HRV signals of drivers were always regarded as stationary signals. The wavelet transform method is a method for analyzing non-stationary signals. The aim of this study is to classify alert and drowsy driving events using the wavelet transform of HRV signals over short time periods and to compare the classification performance of this method with the conventional method that uses fast Fourier transform (FFT-based features. Based on the standard shortest duration for FFT-based short-term HRV evaluation, the wavelet decomposition is performed on 2-min HRV samples, as well as 1-min and 3-min samples for reference purposes. A receiver operation curve (ROC analysis and a support vector machine (SVM classifier are used for feature selection and classification, respectively. The ROC analysis results show that the wavelet-based method performs better than the FFT-based method regardless of the duration of the HRV sample that is used. Finally, based on the real-time requirements for driver drowsiness detection, the SVM classifier is trained using eighty FFT and wavelet-based features that are extracted from 1-min HRV signals from four subjects. The averaged leave-one-out (LOO classification performance using wavelet-based feature is 95% accuracy, 95% sensitivity, and 95% specificity. This is better than the FFT-based results that have 68.8% accuracy, 62.5% sensitivity, and 75% specificity. In addition, the proposed hardware platform is inexpensive and easy-to-use.

  15. Universal design of a microcontroller and IoT system to detect the heart rate

    Science.gov (United States)

    Uwamahoro, Raphael; Mushikiwabeza, Alexie; Minani, Gerard; Mohan Murari, Bhaskar

    2017-11-01

    Heart rate analysis provides vital information of the present condition of the human body. It helps medical professionals in diagnosis of various malfunctions of the body. The limitation of vision impaired and blind people to access medical devices cause a considerable loss of life. In this paper, we intended to develop a heart rate detection system that is usable for people with normal and abnormal vision. The system is based on a non-invasive method of measuring the variation of the tissue blood flow rate by means of a photo transmitter and detector through fingertip known as photoplethysmography (PPG). The signal detected is firstly passed through active low pass filter and then amplified by a two stages high gain amplifier. The amplified signal is feed into the microcontroller to calculate the heart rate and displays the heart beat via sound systems and Liquid Crystal Display (LCD). To distinguish arrhythmia, normal heart rate and abnormal working conditions of the system, recognition is provided in different sounds, LCD readings and Light Emitting Diodes (LED).

  16. Performance evaluation software moving object detection and tracking in videos

    CERN Document Server

    Karasulu, Bahadir

    2013-01-01

    Performance Evaluation Software: Moving Object Detection and Tracking in Videos introduces a software approach for the real-time evaluation and performance comparison of the methods specializing in moving object detection and/or tracking (D&T) in video processing. Digital video content analysis is an important item for multimedia content-based indexing (MCBI), content-based video retrieval (CBVR) and visual surveillance systems. There are some frequently-used generic algorithms for video object D&T in the literature, such as Background Subtraction (BS), Continuously Adaptive Mean-shift (CMS),

  17. Shilling attack detection for recommender systems based on credibility of group users and rating time series.

    Science.gov (United States)

    Zhou, Wei; Wen, Junhao; Qu, Qiang; Zeng, Jun; Cheng, Tian

    2018-01-01

    Recommender systems are vulnerable to shilling attacks. Forged user-generated content data, such as user ratings and reviews, are used by attackers to manipulate recommendation rankings. Shilling attack detection in recommender systems is of great significance to maintain the fairness and sustainability of recommender systems. The current studies have problems in terms of the poor universality of algorithms, difficulty in selection of user profile attributes, and lack of an optimization mechanism. In this paper, a shilling behaviour detection structure based on abnormal group user findings and rating time series analysis is proposed. This paper adds to the current understanding in the field by studying the credibility evaluation model in-depth based on the rating prediction model to derive proximity-based predictions. A method for detecting suspicious ratings based on suspicious time windows and target item analysis is proposed. Suspicious rating time segments are determined by constructing a time series, and data streams of the rating items are examined and suspicious rating segments are checked. To analyse features of shilling attacks by a group user's credibility, an abnormal group user discovery method based on time series and time window is proposed. Standard testing datasets are used to verify the effect of the proposed method.

  18. Supporting the Development and Adoption of Automatic Lameness Detection Systems in Dairy Cattle: Effect of System Cost and Performance on Potential Market Shares.

    Science.gov (United States)

    Van De Gucht, Tim; Van Weyenberg, Stephanie; Van Nuffel, Annelies; Lauwers, Ludwig; Vangeyte, Jürgen; Saeys, Wouter

    2017-10-08

    Most automatic lameness detection system prototypes have not yet been commercialized, and are hence not yet adopted in practice. Therefore, the objective of this study was to simulate the effect of detection performance (percentage missed lame cows and percentage false alarms) and system cost on the potential market share of three automatic lameness detection systems relative to visual detection: a system attached to the cow, a walkover system, and a camera system. Simulations were done using a utility model derived from survey responses obtained from dairy farmers in Flanders, Belgium. Overall, systems attached to the cow had the largest market potential, but were still not competitive with visual detection. Increasing the detection performance or lowering the system cost led to higher market shares for automatic systems at the expense of visual detection. The willingness to pay for extra performance was €2.57 per % less missed lame cows, €1.65 per % less false alerts, and €12.7 for lame leg indication, respectively. The presented results could be exploited by system designers to determine the effect of adjustments to the technology on a system's potential adoption rate.

  19. Two-stage Keypoint Detection Scheme for Region Duplication Forgery Detection in Digital Images.

    Science.gov (United States)

    Emam, Mahmoud; Han, Qi; Zhang, Hongli

    2018-01-01

    In digital image forensics, copy-move or region duplication forgery detection became a vital research topic recently. Most of the existing keypoint-based forgery detection methods fail to detect the forgery in the smooth regions, rather than its sensitivity to geometric changes. To solve these problems and detect points which cover all the regions, we proposed two steps for keypoint detection. First, we employed the scale-invariant feature operator to detect the spatially distributed keypoints from the textured regions. Second, the keypoints from the missing regions are detected using Harris corner detector with nonmaximal suppression to evenly distribute the detected keypoints. To improve the matching performance, local feature points are described using Multi-support Region Order-based Gradient Histogram descriptor. Based on precision-recall rates and commonly tested dataset, comprehensive performance evaluation is performed. The results demonstrated that the proposed scheme has better detection and robustness against some geometric transformation attacks compared with state-of-the-art methods. © 2017 American Academy of Forensic Sciences.

  20. Supplier Performance Evaluation and Rating System (SPEARS)

    International Nuclear Information System (INIS)

    Oged, M.; Warner, D.; Gurbuz, E.

    1993-03-01

    The SSCL Magnet Quality Assurance Department has implemented a Supplier Performance Evaluation and Rating System (SPEARS) to assess supplier performance throughout the development and production stages of the SSCL program. The main objectives of SPEARS are to promote teamwork and recognize performance. This paper examines the current implementation of SPEARS. MSD QA supports the development and production of SSCsuperconducting magnets while implementing the requirements of DOE Order 5700.6C. The MSD QA program is based on the concept of continuous improvement in quality and productivity. The QA program requires that procurement of items and services be controlled to assure conformance to specification. SPEARS has been implemented to meet DOE requirements and to enhance overall confidence in supplier performance. Key elements of SPEARS include supplier evaluation and selection as well as evaluation of furnished quality through source inspection, audit, and receipt inspection. These elements are described in this paper

  1. Supplier Performance Evaluation and Rating System (SPEARS)

    International Nuclear Information System (INIS)

    Oged, M.; Warner, D.G.; Gurbuz, E.

    1994-01-01

    The SSCL Magnet Quality Assurance Department has implemented a Supplier Performance Evaluation and Rating System (SPEARS) to assess supplier performance throughout the development and production stages of the SSCL program. The main objectives of SPEARS are to promote teamwork and recognize performance. This paper examines the current implementation of SPEARS. MSD QA supports the development and production of SSC superconducting magnets while implementing the requirements of DOE Order 5700.6C. The MSD QA program is based on the concept of continuous improvement in quality and productivity. The QA program requires that procurement of items and services be controlled to assure conformance to specification. SPEARS has been implemented to meet DOE requirements and to enhance overall confidence in supplier performance. Key elements of SPEARS include supplier evaluation and selection as well as evaluation of furnished quality through source inspection, audit, and receipt inspection. These elements are described in this paper

  2. Ensemble of classifiers based network intrusion detection system performance bound

    CSIR Research Space (South Africa)

    Mkuzangwe, Nenekazi NP

    2017-11-01

    Full Text Available This paper provides a performance bound of a network intrusion detection system (NIDS) that uses an ensemble of classifiers. Currently researchers rely on implementing the ensemble of classifiers based NIDS before they can determine the performance...

  3. The Influence of Self-Ratings versus Peer Ratings on Supervisors' Performance Judgments.

    Science.gov (United States)

    Makiney; Levy

    1998-06-01

    This study investigated the extent to which supervisors use feedback from outside sources in making performance judgments. A simulation was conducted in which participants with organizational supervisory experience made an initial performance judgment about a profiled employee. Participants then received additional information that was discrepant from their initial judgment (positive or negative) from one of two sources (the profiled employee himself or one of his peers). The direction of the discrepant information and its source interacted in determining final ratings, such that, participants were more likely to use discrepant information to alter their performance judgments in a consistent direction when the source was a peer than when the source was the employee himself. Furthermore, participants' opinions about the usefulness of peer information for performance judgments moderated this interaction. Specifically, participants who believed that information from an employee's peers was useful, were more likely to use discrepant information provided by a peer when making final performance judgments than were participants who did not believe that information from an employee's peers was useful. Copyright 1998 Academic Press.

  4. FPGA-based High-Performance Collision Detection: An Enabling Technique for Image-Guided Robotic Surgery

    Directory of Open Access Journals (Sweden)

    Zhaorui Zhang

    2016-08-01

    Full Text Available Collision detection, which refers to the computational problem of finding the relative placement or con-figuration of two or more objects, is an essential component of many applications in computer graphics and robotics. In image-guided robotic surgery, real-time collision detection is critical for preserving healthy anatomical structures during the surgical procedure. However, the computational complexity of the problem usually results in algorithms that operate at low speed. In this paper, we present a fast and accurate algorithm for collision detection between Oriented-Bounding-Boxes (OBBs that is suitable for real-time implementation. Our proposed Sweep and Prune algorithm can perform a preliminary filtering to reduce the number of objects that need to be tested by the classical Separating Axis Test algorithm, while the OBB pairs of interest are preserved. These OBB pairs are re-checked by the Separating Axis Test algorithm to obtain accurate overlapping status between them. To accelerate the execution, our Sweep and Prune algorithm is tailor-made for the proposed method. Meanwhile, a high performance scalable hardware architecture is proposed by analyzing the intrinsic parallelism of our algorithm, and is implemented on FPGA platform. Results show that our hardware design on the FPGA platform can achieve around 8X higher running speed than the software design on a CPU platform. As a result, the proposed algorithm can achieve a collision frame rate of 1 KHz, and fulfill the requirement for the medical surgery scenario of Robot Assisted Laparoscopy.

  5. Fetal QRS detection and heart rate estimation: a wavelet-based approach

    International Nuclear Information System (INIS)

    Almeida, Rute; Rocha, Ana Paula; Gonçalves, Hernâni; Bernardes, João

    2014-01-01

    Fetal heart rate monitoring is used for pregnancy surveillance in obstetric units all over the world but in spite of recent advances in analysis methods, there are still inherent technical limitations that bound its contribution to the improvement of perinatal indicators. In this work, a previously published wavelet transform based QRS detector, validated over standard electrocardiogram (ECG) databases, is adapted to fetal QRS detection over abdominal fetal ECG. Maternal ECG waves were first located using the original detector and afterwards a version with parameters adapted for fetal physiology was applied to detect fetal QRS, excluding signal singularities associated with maternal heartbeats. Single lead (SL) based marks were combined in a single annotator with post processing rules (SLR) from which fetal RR and fetal heart rate (FHR) measures can be computed. Data from PhysioNet with reference fetal QRS locations was considered for validation, with SLR outperforming SL including ICA based detections. The error in estimated FHR using SLR was lower than 20 bpm for more than 80% of the processed files. The median error in 1 min based FHR estimation was 0.13 bpm, with a correlation between reference and estimated FHR of 0.48, which increased to 0.73 when considering only records for which estimated FHR > 110 bpm. This allows us to conclude that the proposed methodology is able to provide a clinically useful estimation of the FHR. (paper)

  6. Study of the performance of ATLAS muon drift-tube chambers in magntic fields and at high irradiation rates

    Energy Technology Data Exchange (ETDEWEB)

    Valderanis, Chrysostomos

    2012-07-26

    The performance of ATLAS muon drift-tube (MDT) chambers has been studied in detail using high-energy muon beams. The measurements of the drift tube properties in magnetic fields showed that inelastic collisions of the drifting electrons with the CO{sub 2} molecules in the Ar:CO{sub 2} (93:7) gas mixture of the MDT chambers have to be taken into account in the simulation of the drift properties. Such inelastic collisions are now correctly treated by the Garfield simulation programme from version 9 providing an accurate description of the behaviour of the ATLAS muon drift tubes, in particular in the magnetic field. Measurements at the Gamma Irradiation Facility at CERN were performed to study the performance of the MDT chambers in the presence of high {gamma} ray background fluences. The chambers have a spatial resolution better than 40 {mu}m at the nominal background rates expected at the Large Hadron Collider design luminosity of 10{sup 34} cm{sup -2}s{sup -1} and a resolution better than 50 {mu}m for up to five times higher background rates. Efficient muon detection up to background counting rates of 500 kHz per tube corresponding to 35% occupancy was demonstrated.

  7. Detection rate and predictive factors of sessile serrated polyps in an organised colorectal cancer screening programme with immunochemical faecal occult blood test: the EQuIPE study (Evaluating Quality Indicators of the Performance of Endoscopy).

    Science.gov (United States)

    Zorzi, Manuel; Senore, Carlo; Da Re, Filippo; Barca, Alessandra; Bonelli, Luigina Ada; Cannizzaro, Renato; de Pretis, Giovanni; Di Furia, Lucia; Di Giulio, Emilio; Mantellini, Paola; Naldoni, Carlo; Sassatelli, Romano; Rex, Douglas K; Zappa, Marco; Hassan, Cesare

    2017-07-01

    To assess detection rate and predictive factors of sessile serrated polyps (SSPs) in organised colorectal cancer (CRC) screening programmes based on the faecal immunochemical test (FIT). Data from a case series of colonoscopies of FIT-positive subjects were provided by 44 Italian CRC screening programmes. Data on screening history, endoscopic procedure and histology results, and additional information on the endoscopy centre and the endoscopists were collected, including the age-standardised and sex-standardised adenoma detection rate (ADR) of the individual endoscopists. The SSP detection rate (SSP-DR) was assessed for the study population. To identify SSP-predictive factors, multilevel analyses were performed according to patient/centre/endoscopist characteristics. We analysed 72 021 colonoscopies, of which 1295 presented with at least one SSP (SSP-DR 1.8%; 95% CI 1.7% to 1.9%). At the per-patient level, SSP-DR was associated with males (OR 1.35; 95% CI 1.17 to 1.54) and caecal intubation (OR 3.75; 95% CI 2.22 to 6.34), but not with the FIT round. The presence of at least one advanced adenoma was more frequent among subjects with SSPs than those without (OR 2.08; 95% CI 1.86 to 2.33). At the per-endoscopist level, SSP-DR was associated with ADR (third vs first ADR quartile: OR 1.55; 95% CI 1.03 to 2.35; fourth vs first quartile: OR 1.89; 95% CI 1.24 to 2.90). The low prevalence of SSPs and the lack of association with the FIT round argue against SSP as a suitable target for FIT-based organised programmes. Strict association of SSP-DR with the key colonoscopy quality indicators, namely caecal intubation rate and high ADR further marginalises the need for SSP-specific quality indicators in FIT-based programmes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Performance ratings and personality factors in radar controllers.

    Science.gov (United States)

    1970-09-01

    The purpose of the study was to determine whether primary or second-order personality questionnaire factors were related to job performance ratings on the Employee Appraisal Record in a sample of 264 radar controllers. A Pearson correlation matrix wa...

  9. [Research and Design of a System for Detecting Automated External Defbrillator Performance Parameters].

    Science.gov (United States)

    Wang, Kewu; Xiao, Shengxiang; Jiang, Lina; Hu, Jingkai

    2017-09-30

    In order to regularly detect the performance parameters of automated external defibrillator (AED), to make sure it is safe before using the instrument, research and design of a system for detecting automated external defibrillator performance parameters. According to the research of the characteristics of its performance parameters, combing the STM32's stability and high speed with PWM modulation control, the system produces a variety of ECG normal and abnormal signals through the digital sampling methods. Completed the design of the hardware and software, formed a prototype. This system can accurate detect automated external defibrillator discharge energy, synchronous defibrillation time, charging time and other key performance parameters.

  10. A visible light imaging device for cardiac rate detection with reduced effect of body movement

    Science.gov (United States)

    Jiang, Xiaotian; Liu, Ming; Zhao, Yuejin

    2014-09-01

    A visible light imaging system to detect human cardiac rate is proposed in this paper. A color camera and several LEDs, acting as lighting source, were used to avoid the interference of ambient light. From people's forehead, the cardiac rate could be acquired based on photoplethysmography (PPG) theory. The template matching method was used after the capture of video. The video signal was discomposed into three signal channels (RGB) and the region of interest was chosen to take the average gray value. The green channel signal could provide an excellent waveform of pulse wave on the account of green lights' absorptive characteristics of blood. Through the fast Fourier transform, the cardiac rate was exactly achieved. But the research goal was not just to achieve the cardiac rate accurately. With the template matching method, the effects of body movement are reduced to a large extent, therefore the pulse wave can be detected even while people are in the moving state and the waveform is largely optimized. Several experiments are conducted on volunteers, and the results are compared with the ones gained by a finger clamped pulse oximeter. The contrast results between these two ways are exactly agreeable. This method to detect the cardiac rate and the pulse wave largely reduces the effects of body movement and can probably be widely used in the future.

  11. [Determination of atracurium and laudanosine in dog plasma during cardiopulmonary bypass by high performance liquid chromatography with fluorometric detection].

    Science.gov (United States)

    Yang, Yingying; Chen, Mei; Kuang, Yushan; Ye, Liming; Zhang, Wensheng

    2013-06-01

    A high performance liquid chromatographic method coupled with fluorometric detection has been developed for the determination of atracurium and its major metabolite laudanosine in dog plasma. The separation of atracurium and laudanosine was performed on an Agilent Eclipse Plus C18 column, and the mobile phase consisted of 0.03 mol/L dipotassium hydrogen phosphate and acetonitrile (72: 28, v/v) at a flow rate of 1.0 mL/min. Verapamil was used as the internal standard. The sample was extracted by dichloromethane, concentrated and dissolved in the mobile phase. The detection is performed at 240 nm for excitation and 320 nm for emission. The results showed that the linear concentration ranges of the calibration curve were 25 - 5 000 microg/L for atracurium (r = 0.999 0), and 25 - 6 000 microg/L for laudanosine (r = 0.9984). The recoveries were 92.1% - 109.5%. The limits of detection were 3 microg/L for atracurium and 1 microg/L for laudanosine. The RSDs of intra-day and inter-day were less than 10%. The stability tests under various conditions have been performed. The method is specific, sensitive and accurate in the determination of atracurium and laudanosine, and also can be used for the pharmacokinetic investigations of atracurium and laudanosine in plasma.

  12. A statistical analysis on the leak detection performance of ...

    Indian Academy of Sciences (India)

    Chinedu Duru

    2017-11-09

    Nov 9, 2017 ... of underground and overground pipelines with wireless sensor networks through the .... detection performance analysis of pipeline leakage. This study and ..... case and apply to all materials transported through the pipeline.

  13. Measuring Item Fill-Rate Performance in a Finite Horizon

    OpenAIRE

    Douglas J. Thomas

    2005-01-01

    The standard treatment of fill rate relies on stationary and serially independent demand over an infinite horizon. Even if demand is stationary, managers are held accountable for performance over a finite horizon. In a finite horizon, the fill rate is a random variable. Studying the distribution is relevant because a vendor may be subject to financial penalty if she fails to achieve her target fill rate over a specified finite period. It is known that for a zero lead time, base-stock model, t...

  14. Factors influencing the detection rate of drug-related problems in community pharmacy

    DEFF Research Database (Denmark)

    Westerlund, T; Almarsdóttir, Anna Birna; Melander, A

    1999-01-01

    This study analyzes relationships between the number of drug-related problems detected in community pharmacy practice and the educational level and other characteristics of pharmacy personnel and their work sites. Random samples of pharmacists, prescriptionists and pharmacy technicians were drawn...... by each professional. The regression analysis showed the educational level of the professional to have a statistically significant effect on the detection rate, with pharmacists finding on average 2.5 more drug-related problems per 100 patients than prescriptionists and about 3.6 more than technicians....... The results of this study indicate the importance of education and training of pharmacy personnel in detection of drug-related problems. This findings speaks in favor of increasing the pharmacist to other personnel ratio, provided the higher costs will be offset by societal benefits....

  15. Carbon Dioxide Insufflation Increases Colonoscopic Adenoma Detection Rate Compared With Air Insufflation.

    Science.gov (United States)

    Mills, Christopher D; McCamley, Chere; Swan, Michael P

    2018-03-07

    To determine the effect of carbon dioxide insufflation on the most important outcome measure of colonoscopic quality: adenoma detection rate (ADR). Bowel cancer is the second most common cause of cancer deaths in males and females in Australia. Carbon dioxide has in recent times become the insufflation methodology of choice for screening colonoscopy for bowel cancer, as this has been shown to have significant advantages when compared with traditional air insufflation. Endoscopies performed over a period of 9 months immediately before and after the implementation of carbon dioxide insufflation at endoscopy centers were eligible for inclusion. The difference in ADR between the carbon dioxide and air insufflation methods was statistically significant, with an increased ADR in the carbon dioxide group. The superiority of carbon dioxide insufflation was sustained with a logistic regression model, which showed ADR was significantly impacted by insufflation method. Carbon dioxide insufflation is known to reduce abdominal pain, postprocedural duration of abdominal pain, abdominal distension, and analgesic requirements. This study represents for the first time the beneficial effect of carbon dioxide insufflation upon the key quality colonoscopy indicator of ADR.

  16. Computer-aided detection in computed tomography colonography. Current status and problems with detection of early colorectal cancer

    International Nuclear Information System (INIS)

    Morimoto, Tsuyoshi; Nakijima, Yasuo; Iinuma, Gen; Arai, Yasuaki; Shiraishi, Junji; Moriyama, Noriyuki; Beddoe, G.

    2008-01-01

    The aim of this study was to evaluate the usefulness of computer-aided detection (CAD) in diagnosing early colorectal cancer using computed tomography colonography (CTC). A total of 30 CTC data sets for 30 early colorectal cancers in 30 patients were retrospectively reviewed by three radiologists. After primary evaluation, a second reading was performed using CAD findings. The readers evaluated each colorectal segment for the presence or absence of colorectal cancer using five confidence rating levels. To compare the assessment results, the sensitivity and specificity with and without CAD were calculated on the basis of the confidence rating, and differences in these variables were analyzed by receiver operating characteristic (ROC) analysis. The average sensitivities for the detection without and with CAD for the three readers were 81.6% and 75.6%, respectively. Among the three readers, only one reader improved sensitivity with CAD compared to that without. CAD decreased specificity in all three readers. CAD detected 100% of protruding lesions but only 69.2% of flat lesions. On ROC analysis, the diagnostic performance of all three readers was decreased by use of CAD. Currently available CAD with CTC does not improve diagnostic performance for detecting early colorectal cancer. An improved CAD algorithm is required for detecting fiat lesions and reducing the false-positive rate. (author)

  17. Effects of night work, sleep loss and time on task on simulated threat detection performance.

    Science.gov (United States)

    Basner, Mathias; Rubinstein, Joshua; Fomberstein, Kenneth M; Coble, Matthew C; Ecker, Adrian; Avinash, Deepa; Dinges, David F

    2008-09-01

    To investigate the effects of night work and sleep loss on a simulated luggage screening task (SLST) that mimicked the x-ray system used by airport luggage screeners. We developed more than 5,800 unique simulated x-ray images of luggage organized into 31 stimulus sets of 200 bags each. 25% of each set contained either a gun or a knife with low or high target difficulty. The 200-bag stimuli sets were then run on software that simulates an x-ray screening system (SLST). Signal detection analysis was used to obtain measures of hit rate (HR), false alarm rate (FAR), threat detection accuracy (A'), and response bias (B"(D)). Experimental laboratory study 24 healthy nonprofessional volunteers (13 women, mean age +/- SD = 29.9 +/- 6.5 years). Subjects performed the SLST every 2 h during a 5-day period that included a 35 h period of wakefulness that extended to night work and then another day work period after the night without sleep. Threat detection accuracy A' decreased significantly (P work, while both A' (P = 0.001) and HR decreased (P = 0.008) during day work following sleep loss. There were prominent time-on-task effects on response bias B"(D) (P= 0.002) and response latency (P = 0.004), but accuracy A' was unaffected. Both HR and FAR increased significantly with increasing study duration (both P work and sleep loss adversely affect the accuracy of detecting complex real world objects among high levels of background clutter. If the results can be replicated in professional screeners and real work environments, fatigue in luggage screening personnel may pose a threat for air traffic safety unless countermeasures for fatigue are deployed.

  18. Effect of adding screening ultrasonography to screening mammography on patient recall and cancer detection rates: A retrospective study in Japan

    International Nuclear Information System (INIS)

    Tohno, Eriko; Umemoto, Takeshi; Sasaki, Kyoko; Morishima, Isamu; Ueno, Ei

    2013-01-01

    Purpose: To determine whether adding screening ultrasonography to screening mammography can reduce patient recall rates and increase cancer detection rates. Materials and methods: We analyzed the results of mammography and ultrasonography breast screenings performed at the Total Health Evaluation Center Tsukuba, Japan, between April 2011 and March 2012. We also reviewed the modalities and results of diagnostic examinations from women with mammographic abnormalities who visited the Tsukuba Medical Center Hospital for further testing. Results: Of 11,753 women screened, cancer was diagnosed in 10 (0.22%) of the 4529 participants who underwent mammography alone, 23 (0.37%) of the 6250 participants who underwent ultrasonography alone, and 5 (0.51%) of the 974 participants who underwent mammography and ultrasonography. The recall rate due to mammographic abnormalities was 4.9% for women screened only with mammography and 2.6% for those screened with both modalities. The cancer detection rate was 0.22% for women screened only with mammography (positive predictive value, 4.5%) and 0.31% for those screened with both modalities (positive predictive value, 12.0%). Of the 211 lesions presenting as mammographic abnormalities investigated further, diagnostic ultrasonography found no abnormalities in 63 (29.9%) and benign findings in 69 (33.7%). The rest 36.4% needed mammography, cytological or histological examinations or follow-up in addition to diagnostic ultrasonography. Conclusions: It is possible to reduce the recall rate in screening mammography by combining mammography and ultrasonography for breast screening

  19. SU-G-201-03: Automation of High Dose Rate Brachytherapy Quality Assurance: Development of a Radioluminescent Detection System for Simultaneous Detection of Activity, Timing, and Positioning

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, C; Xing, L; Fahimian, B [Stanford University, Stanford, CA (United States)

    2016-06-15

    Purpose: Accuracy of positioning, timing and activity is of critical importance for High Dose Rate (HDR) brachytherapy delivery. Respective measurements via film autoradiography, stop-watches and well chambers can be cumbersome, crude or lack dynamic source evaluation capabilities. To address such limitations, a single device radioluminescent detection system enabling automated real-time quantification of activity, position and timing accuracy is presented and experimentally evaluated. Methods: A radioluminescent sheet was fabricated by mixing Gd?O?S:Tb with PDMS and incorporated into a 3D printed device where it was fixated below a CMOS digital camera. An Ir-192 HDR source (VS2000, VariSource iX) with an effective active length of 5 mm was introduced using a 17-gauge stainless steel needle below the sheet. Pixel intensity values for determining activity were taken from an ROI centered on the source location. A calibration curve relating intensity values to activity was generated and used to evaluate automated activity determination with data gathered over 6 weeks. Positioning measurements were performed by integrating images for an entire delivery and fitting peaks to the resulting profile. Timing measurements were performed by evaluating source location and timestamps from individual images. Results: Average predicted activity error over 6 weeks was .35 ± .5%. The distance between four dwell positions was determined by the automated system to be 1.99 ± .02 cm. The result from autoradiography was 2.00 ± .03 cm. The system achieved a time resolution of 10 msec and determined the dwell time to be 1.01 sec ± .02 sec. Conclusion: The system was able to successfully perform automated detection of activity, positioning and timing concurrently under a single setup. Relative to radiochromic and radiographic film-based autoradiography, which can only provide a static evaluation positioning, optical detection of temporary radiation induced luminescence enables dynamic

  20. Recommendations for the performance rating of flat plate terrestrial photovoltaic solar panels

    Science.gov (United States)

    Treble, F. C.

    1976-01-01

    A review of recommendations for standardizing the performance rating of flat plate terrestrial solar panels is given to develop an international standard code of practice for performance rating. Required data to characterize the performance of a solar panel are listed. Other items discussed are: (1) basic measurement procedures; (2) performance measurement in natural sunlight and simulated sunlight; (3) standard solar cells; (4) the normal incidence method; (5) global method and (6) definition of peak power.

  1. Vehicle Detection with Occlusion Handling, Tracking, and OC-SVM Classification: A High Performance Vision-Based System

    Science.gov (United States)

    Velazquez-Pupo, Roxana; Sierra-Romero, Alberto; Torres-Roman, Deni; Shkvarko, Yuriy V.; Romero-Delgado, Misael

    2018-01-01

    This paper presents a high performance vision-based system with a single static camera for traffic surveillance, for moving vehicle detection with occlusion handling, tracking, counting, and One Class Support Vector Machine (OC-SVM) classification. In this approach, moving objects are first segmented from the background using the adaptive Gaussian Mixture Model (GMM). After that, several geometric features are extracted, such as vehicle area, height, width, centroid, and bounding box. As occlusion is present, an algorithm was implemented to reduce it. The tracking is performed with adaptive Kalman filter. Finally, the selected geometric features: estimated area, height, and width are used by different classifiers in order to sort vehicles into three classes: small, midsize, and large. Extensive experimental results in eight real traffic videos with more than 4000 ground truth vehicles have shown that the improved system can run in real time under an occlusion index of 0.312 and classify vehicles with a global detection rate or recall, precision, and F-measure of up to 98.190%, and an F-measure of up to 99.051% for midsize vehicles. PMID:29382078

  2. Impact of the use of an endorectal coil for 3 T prostate MRI on image quality and cancer detection rate.

    Science.gov (United States)

    Gawlitza, Josephin; Reiss-Zimmermann, Martin; Thörmer, Gregor; Schaudinn, Alexander; Linder, Nicolas; Garnov, Nikita; Horn, Lars-Christian; Minh, Do Hoang; Ganzer, Roman; Stolzenburg, Jens-Uwe; Kahn, Thomas; Moche, Michael; Busse, Harald

    2017-02-01

    This work aims to assess the impact of an additional endorectal coil on image quality and cancer detection rate within the same patients. At a single academic medical center, this transversal study included 41 men who underwent T2- and diffusion-weighted imaging at 3 T using surface coils only or in combination with an endorectal coil in the same session. Two blinded readers (A and B) randomly evaluated all image data in separate sessions. Image quality with respect to localization and staging was rated on a five-point scale. Lesions were classified according to their prostate imaging reporting and data system (PIRADS) score version 1. Standard of reference was provided by whole-mount step-section analysis. Mean image quality scores averaged over all localization-related items were significantly higher with additional endorectal coil for both readers (p < 0.001), corresponding staging-related items were only higher for reader B (p < 0.001). With an endorectal coil, the rate of correctly detecting cancer per patient was significantly higher for reader B (p < 0.001) but not for reader A (p = 0.219). The numbers of histologically confirmed tumor lesions were rather similar for both settings. The subjectively rated 3-T image quality was improved with an endorectal coil. In terms of diagnostic performance, the use of an additional endorectal coil was not superior.

  3. Performance analysis of cognitive multihop relaying with m-QAM detect-and-forward in Nakagami-m fading channels

    KAUST Repository

    Benjillali, Mustapha; Hyadi, Amal; Da Costa, Daniel Benevides Da; Alouini, Mohamed-Slim

    2013-01-01

    In this work, we investigate the performance of cognitive multihop regenerative relaying systems in the "underlay" spectrum sharing scenario. The multiple relays perform "detect-and-forward" relaying strategy to convey a message with an order m quadrature amplitude modulation (m-QAM) from the source to the destination over independent but not necessarily identical Nakagami-m fading channels. We adopt a closed-form analysis framework based on univariate and bivariate Meijer G-functions to derive the end-to-end error performance (in terms of bit and symbol error rates), the outage probability, and the ergodic capacity. Various numerical examples are presented to illustrate the results with a large combination of system and fading parameters, and simulation results confirm the accuracy of our closed-form analysis. © 2013 IEEE.

  4. Performance analysis of cognitive multihop relaying with m-QAM detect-and-forward in Nakagami-m fading channels

    KAUST Repository

    Benjillali, Mustapha

    2013-09-01

    In this work, we investigate the performance of cognitive multihop regenerative relaying systems in the "underlay" spectrum sharing scenario. The multiple relays perform "detect-and-forward" relaying strategy to convey a message with an order m quadrature amplitude modulation (m-QAM) from the source to the destination over independent but not necessarily identical Nakagami-m fading channels. We adopt a closed-form analysis framework based on univariate and bivariate Meijer G-functions to derive the end-to-end error performance (in terms of bit and symbol error rates), the outage probability, and the ergodic capacity. Various numerical examples are presented to illustrate the results with a large combination of system and fading parameters, and simulation results confirm the accuracy of our closed-form analysis. © 2013 IEEE.

  5. Further Validation of the Conner's Adult Attention Deficit/Hyperactivity Rating Scale Infrequency Index (CII) for Detection of Non-Credible Report of Attention Deficit/Hyperactivity Disorder Symptoms.

    Science.gov (United States)

    Cook, Carolyn M; Bolinger, Elizabeth; Suhr, Julie

    2016-06-01

    Attention deficit/hyperactivity disorder (ADHD) can be easily presented in a non-credible manner, through non-credible report of ADHD symptoms and/or by non-credible performance on neuropsychological tests. While most studies have focused on detection of non-credible performance using performance validity tests, there are few studies examining the ability to detect non-credible report of ADHD symptoms. We provide further validation data for a recently developed measure of non-credible ADHD symptom report, the Conner's Adult ADHD Rating Scales (CAARS) Infrequency Index (CII). Using archival data from 86 adults referred for concerns about ADHD, we examined the accuracy of the CII in detecting extreme scores on the CAARS and invalid reporting on validity indices of the Minnesota Multiphasic Personality Inventory-2 Restructured Format (MMPI-2-RF). We also examined the accuracy of the CII in detecting non-credible performance on standalone and embedded performance validity tests. The CII was 52% sensitive to extreme scores on CAARS DSM symptom subscales (with 97% specificity) and 20%-36% sensitive to invalid responding on MMPI-2-RF validity scales (with near 90% specificity), providing further evidence for the interpretation of the CII as an indicator of non-credible ADHD symptom report. However, the CII detected only 18% of individuals who failed a standalone performance validity test (Word Memory Test), with 87.8% specificity, and was not accurate in detecting non-credible performance using embedded digit span cutoffs. Future studies should continue to examine how best to assess for non-credible symptom report in ADHD referrals. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Detecting Parental Deception Using a Behavior Rating Scale during Assessment of Attention-Deficit/Hyperactivity Disorder: An Experimental Study

    Science.gov (United States)

    Norfolk, Philip A.; Floyd, Randy G.

    2016-01-01

    It is often assumed that parents completing behavior rating scales during the assessment of attention-deficit/hyperactivity disorder (ADHD) can deliberately manipulate the outcomes of the assessment. To detect these actions, items designed to detect over-reporting or under-reporting of results are sometimes embedded in such rating scales. This…

  7. Cluster Detection Tests in Spatial Epidemiology: A Global Indicator for Performance Assessment.

    Directory of Open Access Journals (Sweden)

    Aline Guttmann

    Full Text Available In cluster detection of disease, the use of local cluster detection tests (CDTs is current. These methods aim both at locating likely clusters and testing for their statistical significance. New or improved CDTs are regularly proposed to epidemiologists and must be subjected to performance assessment. Because location accuracy has to be considered, performance assessment goes beyond the raw estimation of type I or II errors. As no consensus exists for performance evaluations, heterogeneous methods are used, and therefore studies are rarely comparable. A global indicator of performance, which assesses both spatial accuracy and usual power, would facilitate the exploration of CDTs behaviour and help between-studies comparisons. The Tanimoto coefficient (TC is a well-known measure of similarity that can assess location accuracy but only for one detected cluster. In a simulation study, performance is measured for many tests. From the TC, we here propose two statistics, the averaged TC and the cumulated TC, as indicators able to provide a global overview of CDTs performance for both usual power and location accuracy. We evidence the properties of these two indicators and the superiority of the cumulated TC to assess performance. We tested these indicators to conduct a systematic spatial assessment displayed through performance maps.

  8. Cluster Detection Tests in Spatial Epidemiology: A Global Indicator for Performance Assessment

    Science.gov (United States)

    Guttmann, Aline; Li, Xinran; Feschet, Fabien; Gaudart, Jean; Demongeot, Jacques; Boire, Jean-Yves; Ouchchane, Lemlih

    2015-01-01

    In cluster detection of disease, the use of local cluster detection tests (CDTs) is current. These methods aim both at locating likely clusters and testing for their statistical significance. New or improved CDTs are regularly proposed to epidemiologists and must be subjected to performance assessment. Because location accuracy has to be considered, performance assessment goes beyond the raw estimation of type I or II errors. As no consensus exists for performance evaluations, heterogeneous methods are used, and therefore studies are rarely comparable. A global indicator of performance, which assesses both spatial accuracy and usual power, would facilitate the exploration of CDTs behaviour and help between-studies comparisons. The Tanimoto coefficient (TC) is a well-known measure of similarity that can assess location accuracy but only for one detected cluster. In a simulation study, performance is measured for many tests. From the TC, we here propose two statistics, the averaged TC and the cumulated TC, as indicators able to provide a global overview of CDTs performance for both usual power and location accuracy. We evidence the properties of these two indicators and the superiority of the cumulated TC to assess performance. We tested these indicators to conduct a systematic spatial assessment displayed through performance maps. PMID:26086911

  9. Performance of computer-aided detection of pulmonary nodules in low-dose CT: comparison with double reading by nodule volume

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yingru; Vliegenthart, Rozemarijn; Wang, Ying; Ooijen, Peter M.A. van; Oudkerk, Matthijs [University of Groningen/University Medical Center Groningen, Center for Medical Imaging - North East Netherlands, Department of Radiology, P.O. Box 30.001, Groningen (Netherlands); Bock, Geertruida H. de [University of Groningen/University Medical Center Groningen, Department of Epidemiology, P.O. Box 30.001, Groningen (Netherlands); Klaveren, Rob J. van [Lievensberg Hospital, Department of Pulmonology, P.O. Box 135, Bergen op Zoom (Netherlands); Bogoni, Luca [CAD Group, Siemens Medical Solutions USA, Inc., Malvern, PA (United States); Jong, Pim A. de; Mali, Willem P. [University of Utrecht, Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht (Netherlands)

    2012-10-15

    To evaluate performance of computer-aided detection (CAD) beyond double reading for pulmonary nodules on low-dose computed tomography (CT) by nodule volume. A total of 400 low-dose chest CT examinations were randomly selected from the NELSON lung cancer screening trial. CTs were evaluated by two independent readers and processed by CAD. A total of 1,667 findings marked by readers and/or CAD were evaluated by a consensus panel of expert chest radiologists. Performance was evaluated by calculating sensitivity of pulmonary nodule detection and number of false positives, by nodule characteristics and volume. According to the screening protocol, 90.9 % of the findings could be excluded from further evaluation, 49.2 % being small nodules (less than 50 mm{sup 3}). Excluding small nodules reduced false-positive detections by CAD from 3.7 to 1.9 per examination. Of 151 findings that needed further evaluation, 33 (21.9 %) were detected by CAD only, one of them being diagnosed as lung cancer the following year. The sensitivity of nodule detection was 78.1 % for double reading and 96.7 % for CAD. A total of 69.7 % of nodules undetected by readers were attached nodules of which 78.3 % were vessel-attached. CAD is valuable in lung cancer screening to improve sensitivity of pulmonary nodule detection beyond double reading, at a low false-positive rate when excluding small nodules. circle Computer-aided detection (CAD) has known advantages for computed tomography (CT). (orig.)

  10. Performance of computer-aided detection of pulmonary nodules in low-dose CT: comparison with double reading by nodule volume

    International Nuclear Information System (INIS)

    Zhao, Yingru; Vliegenthart, Rozemarijn; Wang, Ying; Ooijen, Peter M.A. van; Oudkerk, Matthijs; Bock, Geertruida H. de; Klaveren, Rob J. van; Bogoni, Luca; Jong, Pim A. de; Mali, Willem P.

    2012-01-01

    To evaluate performance of computer-aided detection (CAD) beyond double reading for pulmonary nodules on low-dose computed tomography (CT) by nodule volume. A total of 400 low-dose chest CT examinations were randomly selected from the NELSON lung cancer screening trial. CTs were evaluated by two independent readers and processed by CAD. A total of 1,667 findings marked by readers and/or CAD were evaluated by a consensus panel of expert chest radiologists. Performance was evaluated by calculating sensitivity of pulmonary nodule detection and number of false positives, by nodule characteristics and volume. According to the screening protocol, 90.9 % of the findings could be excluded from further evaluation, 49.2 % being small nodules (less than 50 mm 3 ). Excluding small nodules reduced false-positive detections by CAD from 3.7 to 1.9 per examination. Of 151 findings that needed further evaluation, 33 (21.9 %) were detected by CAD only, one of them being diagnosed as lung cancer the following year. The sensitivity of nodule detection was 78.1 % for double reading and 96.7 % for CAD. A total of 69.7 % of nodules undetected by readers were attached nodules of which 78.3 % were vessel-attached. CAD is valuable in lung cancer screening to improve sensitivity of pulmonary nodule detection beyond double reading, at a low false-positive rate when excluding small nodules. circle Computer-aided detection (CAD) has known advantages for computed tomography (CT). (orig.)

  11. Progress in evaluation of human observer visual detection performance using the ROC curve approach

    International Nuclear Information System (INIS)

    Metz, C.E.; Starr, S.J.; Lusted, L.B.; Rossmann, K.

    1976-01-01

    The ROC approach to analysis of human observer detection performance as playing a key role in elucidation the relationships among the physical parameters of an imaging operation, the ability of a human observer to use the image to make decisions regarding the state of health or disease in a medical diagnostic situation, and the medical and social utility of those decisions, was studied. The conventional ROC curve describing observer performance in simple detection tasks can be used to predict observer performance in complex detection tasks. The conventional ROC curve thus provides a description of observer detection performance which is useful in situations more relevant clinically than those for which it is measured. Similar predictions regarding observer performance in identification and recognition tasks are currently being sought. The ROC curve can be used to relate signal detectability to various measures of the diagnostic and social benefit derived from a medical imaging procedure. These relationships provide a means for assessing the relative desirability of alternative diagnostic techniques and can be used to evaluate combinations of diagnostic studies

  12. Selective on-line detection of boronic acids and derivatives in high-performance liquid chromatography eluates by post-column reaction with alizarin

    NARCIS (Netherlands)

    Duval, F.L.; Wardani, P.A.; Zuilhof, H.; Beek, van T.A.

    2015-01-01

    An on-line high-performance liquid chromatography (HPLC) method for the rapid and selective detection of boronic acids in complex mixtures was developed. After optimization experiments at an HPLC flow rate of 0.40 mL/min, the HPLC-separated analytes were mixed post-column with a solution of 75 µM

  13. A Study of the Associations between Conditions of Performance and Characteristics of Performers and New York State Solo Performance Ratings

    Science.gov (United States)

    vonWurmb, Elizabeth C.

    2013-01-01

    This dissertation undertakes an analysis of 1,044 performance evaluations from New York State School Music Association (NYSSMA) Spring Festival solo adjudication ratings of student performers from a large suburban school district. It relies on results of evaluations of observed performances, and takes these evaluations as assessments of what the…

  14. Performance Assessment Method for a Forged Fingerprint Detection Algorithm

    Science.gov (United States)

    Shin, Yong Nyuo; Jun, In-Kyung; Kim, Hyun; Shin, Woochang

    The threat of invasion of privacy and of the illegal appropriation of information both increase with the expansion of the biometrics service environment to open systems. However, while certificates or smart cards can easily be cancelled and reissued if found to be missing, there is no way to recover the unique biometric information of an individual following a security breach. With the recognition that this threat factor may disrupt the large-scale civil service operations approaching implementation, such as electronic ID cards and e-Government systems, many agencies and vendors around the world continue to develop forged fingerprint detection technology, but no objective performance assessment method has, to date, been reported. Therefore, in this paper, we propose a methodology designed to evaluate the objective performance of the forged fingerprint detection technology that is currently attracting a great deal of attention.

  15. Cooperation schemes for rate enhancement in detect-and-forward relay channels

    KAUST Repository

    Benjillali, Mustapha

    2010-05-01

    To improve the spectral efficiency of "Detect-and-Forward" (DetF) half-duplex relaying in fading channels, we propose a cooperation scheme where the relay uses a modulation whose order is higher than the one at the source. In a new common framework, we show that the proposed scheme offers considerable gains - in terms of achievable information rates - compared to the conventional DetF relaying schemes for both orthogonal and non-orthogonal source/relay cooperation. This allows us to propose an adaptive cooperation scheme based on the maximization of the information rate at the destination which needs to observe only the average signal-to-noise ratios of direct and relaying links. ©2010 IEEE.

  16. Effects of task performance, helping, voice, and organizational loyalty on performance appraisal ratings.

    Science.gov (United States)

    Whiting, Steven W; Podsakoff, Philip M; Pierce, Jason R

    2008-01-01

    Despite the fact that several studies have investigated the relationship between organizational citizenship behavior and performance appraisal ratings, the vast majority of these studies have been cross-sectional, correlational investigations conducted in organizational settings that do not allow researchers to establish the causal nature of this relationship. To address this lack of knowledge regarding causality, the authors conducted 2 studies designed to investigate the effects of task performance, helping behavior, voice, and organizational loyalty on performance appraisal evaluations. Findings demonstrated that each of these forms of behavior has significant effects on performance evaluation decisions and suggest that additional attention should be directed at both voice and organizational loyalty as important forms of citizenship behavior aimed at the organization. 2008 APA

  17. Setting Performance Objectives for Radiation Detection Systems in Homeland Security Applications - Economic Models

    International Nuclear Information System (INIS)

    Wood, Thomas W.; Bredt, Ofelia P.; Heasler, Patrick G.; Reichmuth, Barbara A.; Milazzo, Matthew D.

    2005-01-01

    This paper develops simple frameworks for cost minimization of detector systems by trading off the costs of failed detection against the social costs of false alarms. A workable system must have a high degree of certainty in detecting real threats and yet impose low social costs. The models developed here use standard measures of detector performance and derive target detection probabilities and false-alarm tolerance specifications as functions of detector performance, threat traffic densities, and estimated costs

  18. Setting Performance Objectives for Radiation Detection Systems in Homeland Security Applications - Economic Models

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Thomas W.; Bredt, Ofelia P.; Heasler, Patrick G.; Reichmuth, Barbara A.; Milazzo, Matthew D.

    2005-04-28

    This paper develops simple frameworks for cost minimization of detector systems by trading off the costs of failed detection against the social costs of false alarms. A workable system must have a high degree of certainty in detecting real threats and yet impose low social costs. The models developed here use standard measures of detector performance and derive target detection probabilities and false-alarm tolerance specifications as functions of detector performance, threat traffic densities, and estimated costs.

  19. Respiration rate detection based on intensity modulation using plastic optical fiber

    Science.gov (United States)

    Anwar, Zawawi Mohd; Ziran Nurul Sufia, Nor; Hadi, Manap

    2017-11-01

    This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  20. Respiration rate detection based on intensity modulation using plastic optical fiber

    Directory of Open Access Journals (Sweden)

    Mohd Anwar Zawawi

    2017-01-01

    Full Text Available This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  1. Towards Reliable Evaluation of Anomaly-Based Intrusion Detection Performance

    Science.gov (United States)

    Viswanathan, Arun

    2012-01-01

    This report describes the results of research into the effects of environment-induced noise on the evaluation process for anomaly detectors in the cyber security domain. This research was conducted during a 10-week summer internship program from the 19th of August, 2012 to the 23rd of August, 2012 at the Jet Propulsion Laboratory in Pasadena, California. The research performed lies within the larger context of the Los Angeles Department of Water and Power (LADWP) Smart Grid cyber security project, a Department of Energy (DoE) funded effort involving the Jet Propulsion Laboratory, California Institute of Technology and the University of Southern California/ Information Sciences Institute. The results of the present effort constitute an important contribution towards building more rigorous evaluation paradigms for anomaly-based intrusion detectors in complex cyber physical systems such as the Smart Grid. Anomaly detection is a key strategy for cyber intrusion detection and operates by identifying deviations from profiles of nominal behavior and are thus conceptually appealing for detecting "novel" attacks. Evaluating the performance of such a detector requires assessing: (a) how well it captures the model of nominal behavior, and (b) how well it detects attacks (deviations from normality). Current evaluation methods produce results that give insufficient insight into the operation of a detector, inevitably resulting in a significantly poor characterization of a detectors performance. In this work, we first describe a preliminary taxonomy of key evaluation constructs that are necessary for establishing rigor in the evaluation regime of an anomaly detector. We then focus on clarifying the impact of the operational environment on the manifestation of attacks in monitored data. We show how dynamic and evolving environments can introduce high variability into the data stream perturbing detector performance. Prior research has focused on understanding the impact of this

  2. Performance of high-rate gravel-packed oil wells

    Energy Technology Data Exchange (ETDEWEB)

    Unneland, Trond

    2001-05-01

    Improved methods for the prediction, evaluation, and monitoring of performance in high-rate cased-hole gravel-packed oil wells are presented in this thesis. The ability to predict well performance prior to the gravel-pack operations, evaluate the results after the operation, and monitor well performance over time has been improved. This lifetime approach to performance analysis of gravel-packed oil wells contributes to increase oil production and field profitability. First, analytical models available for prediction of performance in gravel-packed oil wells are reviewed, with particular emphasis on high-velocity flow effects. From the analysis of field data from three North Sea oil fields, improved and calibrated cased-hole gravel-pack performance prediction models are presented. The recommended model is based on serial flow through formation sand and gravel in the perforation tunnels. In addition, new correlations for high-velocity flow in high-rate gravel-packed oil wells are introduced. Combined, this improves the performance prediction for gravel-packed oil wells, and specific areas can be targeted for optimized well design. Next, limitations in the current methods and alternative methods for evaluation and comparison of well performance are presented. The most widely used parameter, the skin factor, remains a convenient and important parameter. However, using the skin concept in direct comparisons between wells with different reservoir properties may result in misleading or even invalid conclusions. A discussion of the parameters affecting the skin value, with a clarification of limitations, is included. A methodology for evaluation and comparison of gravel-packed well performance is presented, and this includes the use of results from production logs and the use of effective perforation tunnel permeability as a parameter. This contributes to optimized operational procedures from well to well and from field to field. Finally, the data sources available for

  3. A Novel Passive Islanding Detection Scheme for Distributed Generations Based on Rate of Change of Positive Sequence Component of Voltage and Current

    DEFF Research Database (Denmark)

    Rostami, Ali; Jalilian, Amin; Naderi, Seyed Behzad

    2017-01-01

    ) based wind turbine and synchronous diesel generator DGs by MATLAB/Simulink software. Different non-islanding case studies are taken into account to evaluate the effectiveness of the proposed approach. The simulation results show that the proposed method has advantage of detecting the islanding rapidly......Islanding operation is one of serious hazards of distributed generation (DG) applications. According to IEEE 1547 standard, its occurrence must be detected within two seconds. This paper presents a novel passive islanding detection method based on rate of change of positive sequence component...... of RCPSC and RCPSV exceed the predetermined threshold values, it is concluded that the islanding condition has occurred. Otherwise, it is considered as a non-islanding event. The performance of the proposed method is investigated on a sample network in the presence of doubly fed induction generator (DFIG...

  4. Leadership training to improve adenoma detection rate in screening colonoscopy: A randomised trial

    NARCIS (Netherlands)

    M.F. Kaminski (Michal); J. Anderson (John); R.M. Valori (Roland ); E. Kraszewska (Ewa); M. Rupinski (Maciej); J. Pachlewski (Jacek); E. Wronska (Ewa); M. Bretthauer (Michael); S. Thomas-Gibson (Siwan); E.J. Kuipers (Ernst); J. Regula (J.)

    2016-01-01

    textabstractObjective Suboptimal adenoma detection rate (ADR) at colonoscopy is associated with increased risk of interval colorectal cancer. It is uncertain how ADR might be improved. We compared the effect of leadership training versus feedback only on colonoscopy quality in a countrywide

  5. Individual polyp detection rate in routine daily endoscopy practice depends on case-mix.

    Science.gov (United States)

    Loffeld, R J L F; Liberov, B; Dekkers, P E P

    2015-07-01

    The adenoma detection rate (ADR), a marker of endoscopic quality, is confounded by selection bias. It is not known what the ADR is in normal daily practice. To study the polyp detection rate (PDR) in different endoscopists in the course of years. All consecutive endoscopies of the colon done in 11 years were included. Endoscopies in the regular surveillance programme after polyp removal and after surgery because of colorectal cancer or diverticular disease were scored separately. The number of yearly procedures per endoscopist and presence of polyps, anastomoses, surveillance and cancer were noted. In the period of 11 years, 14,908 consecutive endoscopies of colon and rectum were done by four endoscopists. Two endoscopists had a significantly lower PDR than the other two (p case-mix of patients presented for endoscopy. This result debates the use of the ADR as quality indicator for individual endoscopists.

  6. Performance Analysis of Iterative Channel Estimation and Multiuser Detection in Multipath DS-CDMA Channels

    Science.gov (United States)

    Li, Husheng; Betz, Sharon M.; Poor, H. Vincent

    2007-05-01

    This paper examines the performance of decision feedback based iterative channel estimation and multiuser detection in channel coded aperiodic DS-CDMA systems operating over multipath fading channels. First, explicit expressions describing the performance of channel estimation and parallel interference cancellation based multiuser detection are developed. These results are then combined to characterize the evolution of the performance of a system that iterates among channel estimation, multiuser detection and channel decoding. Sufficient conditions for convergence of this system to a unique fixed point are developed.

  7. Estimation of flow rates through intergranular stress corrosion cracks

    International Nuclear Information System (INIS)

    Collier, R.P.; Norris, D.M.

    1984-01-01

    Experimental studies of critical two-phase water flow, through simulated and actual intergranular stress corrosion cracks, were performed to obtain data to evaluate a leak flow rate model and investigate acoustic transducer effectiveness in detecting and sizing leaks. The experimental program included a parametric study of the effects of crack geometry, fluid stagnation pressure and temperature, and crack surface roughness on leak flow rate. In addition, leak detection, location, and leak size estimation capabilities of several different acoustic transducers were evaluated as functions of leak rate and transducer position. This paper presents flow rate data for several different cracks and fluid conditions. It also presents the minimum flow rate detected with the acoustic sensors and a relationship between acoustic signal strength and leak flow rate

  8. Binary and multi-category ratings in a laboratory observer performance study: a comparison.

    Science.gov (United States)

    Gur, David; Bandos, Andriy I; King, Jill L; Klym, Amy H; Cohen, Cathy S; Hakim, Christiane M; Hardesty, Lara A; Ganott, Marie A; Perrin, Ronald L; Poller, William R; Shah, Ratan; Sumkin, Jules H; Wallace, Luisa P; Rockette, Howard E

    2008-10-01

    The authors investigated radiologists, performances during retrospective interpretation of screening mammograms when using a binary decision whether to recall a woman for additional procedures or not and compared it with their receiver operating characteristic (ROC) type performance curves using a semi-continuous rating scale. Under an Institutional Review Board approved protocol nine experienced radiologists independently rated an enriched set of 155 examinations that they had not personally read in the clinic, mixed with other enriched sets of examinations that they had individually read in the clinic, using both a screening BI-RADS rating scale (recall/not recall) and a semi-continuous ROC type rating scale (0 to 100). The vertical distance, namely the difference in sensitivity levels at the same specificity levels, between the empirical ROC curve and the binary operating point were computed for each reader. The vertical distance averaged over all readers was used to assess the proximity of the performance levels under the binary and ROC-type rating scale. There does not appear to be any systematic tendency of the readers towards a better performance when using either of the two rating approaches, namely four readers performed better using the semi-continuous rating scale, four readers performed better with the binary scale, and one reader had the point exactly on the empirical ROC curve. Only one of the nine readers had a binary "operating point" that was statistically distant from the same reader's empirical ROC curve. Reader-specific differences ranged from -0.046 to 0.128 with an average width of the corresponding 95% confidence intervals of 0.2 and p-values ranging for individual readers from 0.050 to 0.966. On average, radiologists performed similarly when using the two rating scales in that the average distance between the run in individual reader's binary operating point and their ROC curve was close to zero. The 95% confidence interval for the fixed

  9. Transfer Rate Edited experiment for the selective detection of Chemical Exchange via Saturation Transfer (TRE-CEST)

    Science.gov (United States)

    Friedman, Joshua I.; Xia, Ding; Regatte, Ravinder R.; Jerschow, Alexej

    2015-07-01

    Chemical Exchange Saturation Transfer (CEST) magnetic resonance experiments have become valuable tools in magnetic resonance for the detection of low concentration solutes with far greater sensitivity than direct detection methods. Accurate measures of rates of chemical exchange provided by CEST are of particular interest to biomedical imaging communities where variations in chemical exchange can be related to subtle variations in biomarker concentration, temperature and pH within tissues using MRI. Despite their name, however, traditional CEST methods are not truly selective for chemical exchange and instead detect all forms of magnetization transfer including through-space NOE. This ambiguity crowds CEST spectra and greatly complicates subsequent data analysis. We have developed a Transfer Rate Edited CEST experiment (TRE-CEST) that uses two different types of solute labeling in order to selectively amplify signals of rapidly exchanging proton species while simultaneously suppressing 'slower' NOE-dominated magnetization transfer processes. This approach is demonstrated in the context of both NMR and MRI, where it is used to detect the labile amide protons of proteins undergoing chemical exchange (at rates ⩾ 30 s-1) while simultaneously eliminating signals originating from slower (∼5 s-1) NOE-mediated magnetization transfer processes. TRE-CEST greatly expands the utility of CEST experiments in complex systems, and in-vivo, in particular, where it is expected to improve the quantification of chemical exchange and magnetization transfer rates while enabling new forms of imaging contrast.

  10. Improving TCP Network Performance by Detecting and Reacting to Packet Reordering

    Science.gov (United States)

    Kruse, Hans; Ostermann, Shawn; Allman, Mark

    2003-01-01

    There are many factors governing the performance of TCP-basec applications traversing satellite channels. The end-to-end performance of TCP is known to be degraded by the reordering, delay, noise and asymmetry inherent in geosynchronous systems. This result has been largely based on experiments that evaluate the performance of TCP in single flow tests. While single flow tests are useful for deriving information on the theoretical behavior of TCP and allow for easy diagnosis of problems they do not represent a broad range of realistic situations and therefore cannot be used to authoritatively comment on performance issues. The experiments discussed in this report test TCP s performance in a more dynamic environment with competing traffic flows from hundreds of TCP connections running simultaneously across the satellite channel. Another aspect we investigate is TCP's reaction to bit errors on satellite channels. TCP interprets loss as a sign of network congestion. This causes TCP to reduce its transmission rate leading to reduced performance when loss is due to corruption. We allowed the bit error rate on our satellite channel to vary widely and tested the performance of TCP as a function of these bit error rates. Our results show that the average performance of TCP on satellite channels is good even under conditions of loss as high as bit error rates of 10(exp -5)

  11. Computer-aided Detection of Lung Cancer on Chest Radiographs: Effect on Observer Performance

    NARCIS (Netherlands)

    de Hoop, Bartjan; de Boo, Diederik W.; Gietema, Hester A.; van Hoorn, Frans; Mearadji, Banafsche; Schijf, Laura; van Ginneken, Bram; Prokop, Mathias; Schaefer-Prokop, Cornelia

    2010-01-01

    Purpose: To assess how computer-aided detection (CAD) affects reader performance in detecting early lung cancer on chest radiographs. Materials and Methods: In this ethics committee-approved study, 46 individuals with 49 computed tomographically (CT)-detected and histologically proved lung cancers

  12. Time-Frequency Analysis of Terahertz Radar Signals for Rapid Heart and Breath Rate Detection

    National Research Council Canada - National Science Library

    Massar, Melody L

    2008-01-01

    We develop new time-frequency analytic techniques which facilitate the detection of a person's heart and breath rates from the Doppler shift the movement of their body induces in a terahertz radar signal...

  13. Computer-aided detection of pulmonary embolism: Influence on radiologists' detection performance with respect to vessel segments

    International Nuclear Information System (INIS)

    Das, Marco; Muehlenbruch, Georg; Helm, Anita; Guenther, Rolf W.; Wildberger, Joachim E.; Bakai, Annemarie; Salganicoff, Marcos; Liang, Jianming; Wolf, Matthias; Stanzel, Sven

    2008-01-01

    The purpose was to assess the sensitivity of a CAD software prototype for the detection of pulmonary embolism in MDCT chest examinations with regard to vessel level and to assess the influence on radiologists' detection performance. Forty-three patients with suspected PE were included in this retrospective study. MDCT chest examinations with a standard PE protocol were acquired at a 16-slice MDCT. All patient data were read by three radiologists (R1, R2, R3), and all thrombi were marked. A CAD prototype software was applied to all datasets, and each finding of the software was analyzed with regard to vessel level. The standard of reference was assessed in a consensus read. Sensitivity for the radiologists and CAD software was assessed. Thirty-three patients were positive for PE, with a total of 215 thrombi. The mean overall sensitivity for the CAD software alone was 83% (specificity, 80%). Radiologist sensitivity was 77% = R3, 82% = R2, and R1 = 87%. With the aid of the CAD software, sensitivities increased to 98% (R1), 93% (R2), and 92% (R3) (p<0.0001). CAD performance at the lobar level was 87%, at the segmental 90% and at the subsegmental 77%. With the use of CAD for PE, the detection performance of radiologists can be improved. (orig.)

  14. Market response to the public display of energy performance rating at property sales

    DEFF Research Database (Denmark)

    Jensen, Ole Michael; Hansen, Anders Rhiger; Kragh, Jesper

    2016-01-01

    Energy labels have generally received positive response from consumers and have moved the market for white goods and cars in the direction of more energy-efficient products. On the real estate market, it was expected that an energy label, rating the energy performance of a property based on a nat......Energy labels have generally received positive response from consumers and have moved the market for white goods and cars in the direction of more energy-efficient products. On the real estate market, it was expected that an energy label, rating the energy performance of a property based...... on a national energy performance certificate (EPC) might receive similar response. However, in Denmark no response to the energy performance rating was observed for 15 years. This was a surprise considering that Denmark was the first country to implement an A to G rating of the energy performance of buildings...

  15. Detection Range of Airborne Magnetometers in Magnetic Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Chengjing Li

    2015-11-01

    Full Text Available Airborne magnetometers are utilized for the small-range search, precise positioning, and identification of the ferromagnetic properties of underwater targets. As an important performance parameter of sensors, the detection range of airborne magnetometers is commonly set as a fixed value in references regardless of the influences of environment noise, target magnetic properties, and platform features in a classical model to detect airborne magnetic anomalies. As a consequence, deviation in detection ability analysis is observed. In this study, a novel detection range model is proposed on the basis of classic detection range models of airborne magnetometers. In this model, probability distribution is applied, and the magnetic properties of targets and the environment noise properties of a moving submarine are considered. The detection range model is also constructed by considering the distribution of the moving submarine during detection. A cell-averaging greatest-of-constant false alarm rate test method is also used to calculate the detection range of the model at a desired false alarm rate. The detection range model is then used to establish typical submarine search probabilistic models. Results show that the model can be used to evaluate not only the effects of ambient magnetic noise but also the moving and geomagnetic features of the target and airborne detection platform. The model can also be utilized to display the actual operating range of sensor systems.

  16. Obesity detection rate among primary school students in the People's Republic of China: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Jin Y

    2013-10-01

    Full Text Available Yue-long Jin,* Ling-ling Ding,* Ying-shui Yao, Xiu-li Song, Hui Tang, Lian-ping He, Yan ChenFaculty of Epidemiology and Statistics, School of Public Health, Wannan Medical College, Anhui, People's Republic of China*These authors contributed equally to this workBackground: Obesity has become a major public health problem worldwide. The prevalence of obesity is rising alarmingly among children and adolescents in the People's Republic of China, with an estimated 120 million now in the obese range. It is estimated that 8% of children in the People's Republic of China are obese and 12% are overweight.Methods: Eligible papers on the prevalence of obesity among primary school students in the People's Republic of China and published between 2006 and 2011 were retrieved from PubMed and from online Chinese periodicals, ie, the full-text databases of VIP, the Chinese National Knowledge Infrastructure, and Wan Fang. Meta-Analyst software was used to collate and analyze the detection rates cited in the papers retrieved.Results: After evaluation of the quality of the papers, 25 were finally included, giving a total sample population size for investigation of obesity of 219,763, in which 28,121 cases were detected. Meta-analysis showed that the combined obesity detection rate was 10.4% (95% confidence interval 8.6–12.6 among primary school students in the People's Republic of China, with a higher detection rate in boys (12.6% than in girls (7.2%. The prevalence of obesity was higher in the north (11.8% than in the south (9.5%, east (11.6%, and mid-west (8.0% regions. Obesity defined according to the World Health Organization weight-for-height standard (14.3% was higher than that using age-specific and gender-specific cutoff points for body mass index (9.0%.Conclusion: Our meta-analysis found an obesity prevalence rate of 10.4%, which does not seem as high as previous reports of childhood obesity rates in other countries. However, the prevalence of childhood

  17. Exploration of available feature detection and identification systems and their performance on radiographs

    Science.gov (United States)

    Wantuch, Andrew C.; Vita, Joshua A.; Jimenez, Edward S.; Bray, Iliana E.

    2016-10-01

    Despite object detection, recognition, and identification being very active areas of computer vision research, many of the available tools to aid in these processes are designed with only photographs in mind. Although some algorithms used specifically for feature detection and identification may not take explicit advantage of the colors available in the image, they still under-perform on radiographs, which are grayscale images. We are especially interested in the robustness of these algorithms, specifically their performance on a preexisting database of X-ray radiographs in compressed JPEG form, with multiple ways of describing pixel information. We will review various aspects of the performance of available feature detection and identification systems, including MATLABs Computer Vision toolbox, VLFeat, and OpenCV on our non-ideal database. In the process, we will explore possible reasons for the algorithms' lessened ability to detect and identify features from the X-ray radiographs.

  18. Narrow Band Imaging Enhances the Detection Rate of Penetration and Aspiration in FEES.

    Science.gov (United States)

    Nienstedt, Julie C; Müller, Frank; Nießen, Almut; Fleischer, Susanne; Koseki, Jana-Christiane; Flügel, Till; Pflug, Christina

    2017-06-01

    Narrow band imaging (NBI) is widely used in gastrointestinal, laryngeal, and urological endoscopy. Its original purpose was to visualize vessels and epithelial irregularities. Based on our observation that adding NBI to common white light (WL) improves the contrast of the test bolus in fiberoptic endoscopic evaluation of swallowing (FEES), we now investigated the potential value of NBI in swallowing disorders. 148 FEES images were analyzed from 74 consecutive patients with swallowing disorders, including 74 with and 74 without NBI. All images were evaluated by four dysphagia specialists. Findings were classified according to Rosenbek's penetration-aspiration scale modified for evaluating these FEES images. Intra- and inter-rater reliability was determined as well as observer confidence. A better visualization of the bolus is the main advantage of NBI in FEES. This generally leads to sharper optical contrasts and better detection of small bolus quantities. Accordingly, NBI enhances the detection rate of penetration and aspiration. On average, identification of laryngeal penetration increased from 40 to 73% and of aspiration from 13 to 24% (each p dysphagia evaluation and shortening FEES evaluation time. It leads to a markedly higher detection rate of pathological findings. The significantly better intra- and inter-rater reliability argues further for a better overall reproducibly of FEES interpretation.

  19. An Advanced Deep Learning Approach for Ki-67 Stained Hotspot Detection and Proliferation Rate Scoring for Prognostic Evaluation of Breast Cancer.

    Science.gov (United States)

    Saha, Monjoy; Chakraborty, Chandan; Arun, Indu; Ahmed, Rosina; Chatterjee, Sanjoy

    2017-06-12

    Being a non-histone protein, Ki-67 is one of the essential biomarkers for the immunohistochemical assessment of proliferation rate in breast cancer screening and grading. The Ki-67 signature is always sensitive to radiotherapy and chemotherapy. Due to random morphological, color and intensity variations of cell nuclei (immunopositive and immunonegative), manual/subjective assessment of Ki-67 scoring is error-prone and time-consuming. Hence, several machine learning approaches have been reported; nevertheless, none of them had worked on deep learning based hotspots detection and proliferation scoring. In this article, we suggest an advanced deep learning model for computerized recognition of candidate hotspots and subsequent proliferation rate scoring by quantifying Ki-67 appearance in breast cancer immunohistochemical images. Unlike existing Ki-67 scoring techniques, our methodology uses Gamma mixture model (GMM) with Expectation-Maximization for seed point detection and patch selection and deep learning, comprises with decision layer, for hotspots detection and proliferation scoring. Experimental results provide 93% precision, 0.88% recall and 0.91% F-score value. The model performance has also been compared with the pathologists' manual annotations and recently published articles. In future, the proposed deep learning framework will be highly reliable and beneficial to the junior and senior pathologists for fast and efficient Ki-67 scoring.

  20. RNA interference for performance enhancement and detection in doping control.

    Science.gov (United States)

    Kohler, Maxie; Schänzer, Wilhelm; Thevis, Mario

    2011-10-01

    RNA interference represents a comparably new route of regulating and manipulating specific gene expression. Promising results were obtained in experimental therapies aim at the treatment of different kinds of diseases including cancer, diabetes mellitus or Dychenne muscular dystrophy. While studies on down-regulation efficiency are often performed by analyzing the regulated protein, the direct detection of small, interfering RNA molecules and antisense oligonucleotides is of great interest for the investigation of the metabolism and degradation and also for the detection of a putative misuse of these molecules in sports. Myostatin down-regulation was shown to result in increased performance and muscle growth and the regulation of several other proteins could be relevant for performance enhancement. This mini-review summarizes current approaches for the mass spectrometric analysis of siRNA and antisense oligonucleotides from biological matrices and the available data on biodistribution, metabolism, and half-life of relevant substances are discussed. Copyright © 2011 John Wiley & Sons, Ltd.

  1. Performance of an iPad Application to Detect Moderate and Advanced Visual Field Loss in Nepal.

    Science.gov (United States)

    Johnson, Chris A; Thapa, Suman; George Kong, Yu Xiang; Robin, Alan L

    2017-10-01

    To evaluate the accuracy and efficiency of Visual Fields Easy (VFE), a free iPad app, for performing suprathreshold perimetric screening. Prospective, cross-sectional validation study. We performed screening visual fields using a calibrated iPad 2 with the VFE application on 206 subjects (411 eyes): 210 normal (NL), 183 glaucoma (GL), and 18 diabetic retinopathy (DR) at Tilganga Institute of Ophthalmology, Kathmandu, Nepal. We correlated the results with a Humphrey Field Analyzer using 24-2 SITA Standard tests on 373 of these eyes (198 NL, 160 GL, 15 DR). The number of missed locations on the VFE correlated with mean deviation (MD, r = 0.79), pattern standard deviation (PSD, r = 0.60), and number of locations that were worse than the 95% confidence limits for total deviation (r = 0.51) and pattern deviation (r = 0.68) using SITA Standard. iPad suprathreshold perimetry was able to detect most visual field deficits with moderate (MD of -6 to -12 dB) and advanced (MD worse than -12 dB) loss, but had greater difficulty in detecting early (MD better than -6 dB) loss, primarily owing to an elevated false-positive response rate. The average time to perform the Visual Fields Easy test was 3 minutes, 18 seconds (standard deviation = 16.88 seconds). The Visual Fields Easy test procedure is a portable, fast, effective procedure for detecting moderate and advanced visual field loss. Improvements are currently underway to monitor eye and head tracking during testing, reduce testing time, improve performance, and eliminate the need to touch the video screen surface. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Radionuclide release rates from spent fuel for performance assessment modeling

    International Nuclear Information System (INIS)

    Curtis, D.B.

    1994-01-01

    In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different approach to obtaining a numerical measure and each has its limitations. There is no way to obtain an unambiguous measure of this or any parameter used in performance assessment codes for evaluating the effects of processes operative over many millennia. The examples are intended to suggest by example that in the absence of the ability to evaluate accuracy and precision, consistency of a broadly based set of data can be used as circumstantial evidence to defend the choice of parameters used in performance assessments

  3. Digitizing Tablet and Fahn–Tolosa–Marín Ratings of Archimedes Spirals have Comparable Minimum Detectable Change in Essential Tremor

    Directory of Open Access Journals (Sweden)

    Rodger J. Elble

    2017-07-01

    Full Text Available Background: Drawing Archimedes spirals is a popular and valid method of assessing action tremor in the upper limbs. We performed the first blinded comparison of Fahn–Tolosa–Marín (FTM ratings and tablet measures of essential tremor to determine if a digitizing tablet is better than 0–4 ratings in detecting changes in essential tremor that exceed random variability in tremor amplitude.Methods: The large and small spirals of FTM were drawn with each hand on two consecutive days by 14 men and four women (age 60±8.7 years [mean±SD] with mild to severe essential tremor. The drawings were simultaneously digitized with a digitizing tablet. Tremor in each digitized drawing was computed with spectral analysis in an independent laboratory, blinded to the clinical ratings. The mean peak-to-peak tremor displacement (cm in the four spirals and mean FTM ratings were compared statistically.Results: Test–retest intraclass correlations (ICCs (two-way random single measures, absolute agreement were excellent for the FTM ratings (ICC 0.90, 95% CI 0.76–0.96 and tablet (ICC 0.97, 95% CI 0.91–0.99. Log10 tremor amplitude (T and FTM were strongly correlated (logT = αFTM + β, α≈0.6, β≈–1.27, r = 0.94. The minimum detectable change for the tablet and FTM were 51% and 67% of the initial assessment.Discussion: Digitizing tablets are much more precise than clinical ratings, but this advantage is mitigated by the natural variability in tremor. Nevertheless, the digitizing tablet is a robust method of quantifying tremor that can be used in lieu of or in combination with clinical ratings.

  4. Quantifying Human Performance of a Dynamic Military Target Detection Task: An Application of the Theory of Signal Detection.

    Science.gov (United States)

    1995-06-01

    applied to analyze numerous experimental tasks (Macmillan and Creelman , 1991). One of these tasks, target detection, is the subject research. In...between each associated pair of false alarm rate and hit rate z-scores is d’ for the bias level associated with the pairing (Macmillan and Creelman , 1991...unequal variance in normal distributions (Macmillan and Creelman , 1991). 61 1966). It is described in detail for the interested reader by Green and

  5. Doppler method leak detection for LMFBR steam generators. Pt. 3. Investigation of detection sensitivity and method

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi; Kinoshita, Izumi

    2001-01-01

    To prevent the expansion of tube damage and to maintain structural integrity in the steam generators (SGs) of a fast breeder reactor (FBR), it is necessary to detect precisely and immediately any leakage of water from heat transfer tubes. Therefore, the Doppler method was developed. Previous studies have revealed that, in the SG full-sector model that simulates actual SGs, the Doppler method can detect bubbles of 0.4 l/s within a few seconds. However in consideration of the dissolution rate of hydrogen generated by a sodium-water reaction even from a small water leak, it is necessary to detect smaller leakages of water from the heat transfer tubes. The detection sensitivity of the Doppler method and the influence of background noise were experimentally investigated. In-water experiments were performed using the SG model. The results show that the Doppler method can detect bubbles of 0.01 l/s (equivalent to a water leak rate of about 0.01 g/s) within a few seconds and that the background noise has little effect on water leak detection performance. The Doppler method thus has great potential for the detection of water leakage in SGs. (author)

  6. [Relationship between performance rating and risk of low back pain in manufacturing line workers].

    Science.gov (United States)

    Higuchi, Yoshiyuki; Funahashi, Atsushi; Izumi, Hiroyuki; Kumashinro, Masaharu

    2012-03-01

    It is possible that the performance rating of line workers is affected by the risk factors for musculoskeletal disorders that are included in their work more so than by the actual takt time. To investigate whether performance rating relates to the risk factors for musculoskeletal disorders, we analyzed a dataset obtained from a self-administered questionnaire answered by assembly line workers (n=1579). As a result, performance rating had a significant association with unsuitable work environments, poor working postures and handling of heavy loads. The workers who reported the fastest rating had a higher exposure than others to the risk factors for occupational low back pain. The results of our study support the effectiveness of performance rating as an index of work burden.

  7. A comparison of directed search target detection versus in-scene target detection in Worldview-2 datasets

    Science.gov (United States)

    Grossman, S.

    2015-05-01

    Since the events of September 11, 2001, the intelligence focus has moved from large order-of-battle targets to small targets of opportunity. Additionally, the business community has discovered the use of remotely sensed data to anticipate demand and derive data on their competition. This requires the finer spectral and spatial fidelity now available to recognize those targets. This work hypothesizes that directed searches using calibrated data perform at least as well as inscene manually intensive target detection searches. It uses calibrated Worldview-2 multispectral images with NEF generated signatures and standard detection algorithms to compare bespoke directed search capabilities against ENVI™ in-scene search capabilities. Multiple execution runs are performed at increasing thresholds to generate detection rates. These rates are plotted and statistically analyzed. While individual head-to-head comparison results vary, 88% of the directed searches performed at least as well as in-scene searches with 50% clearly outperforming in-scene methods. The results strongly support the premise that directed searches perform at least as well as comparable in-scene searches.

  8. Accountability and need for cognition effects on contrast, halo, and accuracy in performance ratings.

    Science.gov (United States)

    Palmer, Jerry K; Feldman, Jack M

    2005-03-01

    In the present study, the authors investigated the effects of accountability and need for cognition on contrast errors, halo, and accuracy of performance ratings examined in good and poor performance context conditions, as well as in a context-free control condition. The accountability manipulation reduced the contrast effect and also modified rater recall of good ratee behavior. Accountability reduced halo in ratings and increased rating accuracy in a poor performance context. Accountability also interacted with need for cognition in predicting individual rater halo.

  9. Performance of Molecular Approaches for Aspergillus Detection and Azole Resistance Surveillance in Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Hélène Guegan

    2018-03-01

    Full Text Available Aspergillus fumigatus triazole resistance is an emerging concern for treating chronically infected/colonized patients. This study sought to evaluate the performance of PCR assays to detect Aspergillus fungi together with azole resistance in sputum samples from cystic fibrosis (CF patients. In total, 119 sputum samples from 87 CF patients were prospectively processed for Aspergillus detection by means of mycological culture and four qPCR assays, 2 in-house methods and two commercial multiplex real-time PCR assays simultaneously detecting Aspergillus and the most relevant cyp51A gene mutations (MycoGENIE® and AsperGenius®. Azole susceptibility of A. fumigatus isolates was assessed using Etest® method and cyp51A gene mutation were characterized by sequencing. The overall rate of Aspergillus detection with the four qPCR assays ranged from 47.9 to 57.1%, contrasting with 42/119 (35.3% positive cultures with A. fumigatus. The high sensitivity of PCR on sputum could then contribute to more effective grading of Aspergillus disease in CF patients. Five out of 41 isolated strains (12.2% exhibited azole-resistant MIC patterns, three of which harbored cyp51A mutations and only 1/3 with the sequence TR34/L98H. Combined with culture, PCR assay achieved high sensitivity Aspergillus screening in CF samples. However, cyp51A targeting was only moderately effective for azole resistance monitoring, while Aspergillus resistance remains of great concern.

  10. Rate of detection of advanced neoplasms in proximal colon by simulated sigmoidoscopy vs fecal immunochemical tests.

    Science.gov (United States)

    Castells, Antoni; Quintero, Enrique; Álvarez, Cristina; Bujanda, Luis; Cubiella, Joaquín; Salas, Dolores; Lanas, Angel; Carballo, Fernando; Morillas, Juan Diego; Hernández, Cristina; Jover, Rodrigo; Hijona, Elizabeth; Portillo, Isabel; Enríquez-Navascués, José M; Hernández, Vicent; Martínez-Turnes, Alfonso; Menéndez-Villalva, Carlos; González-Mao, Carmen; Sala, Teresa; Ponce, Marta; Andrés, Mercedes; Teruel, Gloria; Peris, Antonio; Sopeña, Federico; González-Rubio, Francisca; Seoane-Urgorri, Agustín; Grau, Jaume; Serradesanferm, Anna; Pozo, Àngels; Pellisé, Maria; Balaguer, Francesc; Ono, Akiko; Cruzado, José; Pérez-Riquelme, Francisco; Alonso-Abreu, Inmaculada; Carrillo-Palau, Marta; de la Vega-Prieto, Mariola; Iglesias, Rosario; Amador, Javier; Blanco, José Manuel; Sastre, Rocio; Ferrándiz, Juan; González-Hernández, Ma José; Andreu, Montserrat; Bessa, Xavier

    2014-10-01

    We compared the ability of biennial fecal immunochemical testing (FIT) and one-time sigmoidoscopy to detect colon side-specific advanced neoplasms in a population-based, multicenter, nationwide, randomized controlled trial. We identified asymptomatic men and women, 50-69 years old, through community health registries and randomly assigned them to groups that received a single colonoscopy examination or biennial FIT. Sigmoidoscopy yield was simulated from results obtained from the colonoscopy group, according to the criteria proposed in the UK Flexible Sigmoidoscopy Trial for colonoscopy referral. Patients who underwent FIT and were found to have ≥75 ng hemoglobin/mL were referred for colonoscopy. Data were analyzed from 5059 subjects in the colonoscopy group and 10,507 in the FIT group. The main outcome was rate of detection of any advanced neoplasm proximal to the splenic flexure. Advanced neoplasms were detected in 317 subjects (6.3%) in the sigmoidoscopy simulation group compared with 288 (2.7%) in the FIT group (odds ratio for sigmoidoscopy, 2.29; 95% confidence interval, 1.93-2.70; P = .0001). Sigmoidoscopy also detected advanced distal neoplasia in a higher percentage of patients than FIT (odds ratio, 2.61; 95% confidence interval, 2.20-3.10; P = .0001). The methods did not differ significantly in identifying patients with advanced proximal neoplasms (odds ratio, 1.17; 95% confidence interval, 0.78-1.76; P = .44). This was probably due to the lower performance of both strategies in detecting patients with proximal lesions (sigmoidoscopy detected these in 19.1% of patients and FIT in 14.9% of patients) vs distal ones (sigmoidoscopy detected these in 86.8% of patients and FIT in 33.5% of patients). Sigmoidoscopy, but not FIT, detected proximal lesions in lower percentages of women (especially those 50-59 years old) than men. Sigmoidoscopy and FIT have similar limitations in detecting advanced proximal neoplasms, which depend on patients' characteristics

  11. Invariance of the bit error rate in the ancilla-assisted homodyne detection

    International Nuclear Information System (INIS)

    Yoshida, Yuhsuke; Takeoka, Masahiro; Sasaki, Masahide

    2010-01-01

    We investigate the minimum achievable bit error rate of the discrimination of binary coherent states with the help of arbitrary ancillary states. We adopt homodyne measurement with a common phase of the local oscillator and classical feedforward control. After one ancillary state is measured, its outcome is referred to the preparation of the next ancillary state and the tuning of the next mixing with the signal. It is shown that the minimum bit error rate of the system is invariant under the following operations: feedforward control, deformations, and introduction of any ancillary state. We also discuss the possible generalization of the homodyne detection scheme.

  12. High-Performance X-ray Detection in a New Analytical Electron Microscope

    Science.gov (United States)

    Lyman, C. E.; Goldstein, J. I.; Williams, D. B.; Ackland, D. W.; vonHarrach, S.; Nicholls, A. W.; Statham, P. J.

    1994-01-01

    X-ray detection by energy-dispersive spectrometry in the analytical electron microscope (AEM) is often limited by low collected X-ray intensity (P), modest peak-to-background (P/B) ratios, and limitations on total counting time (tau) due to specimen drift and contamination. A new AFM has been designed with maximization of P. P/B, and tau as the primary considerations. Maximization of P has been accomplished by employing a field-emission electron gun, X-ray detectors with high collection angles, high-speed beam blanking to allow only one photon into the detector at a time, and simultaneous collection from two detectors. P/B has been maximized by reducing extraneous background signals generated at the specimen holder, the polepieces and the detector collimator. The maximum practical tau has been increased by reducing specimen contamination and employing electronic drift correction. Performance improvments have been measured using the NIST standard Cr thin film. The 0-3 steradian solid angle of X-ray collection is the highest value available. The beam blanking scheme for X-ray detection provides 3-4 times greater throughput of X-rays at high count rates into a recorded spectrum than normal systems employing pulse-pileup rejection circuits. Simultaneous X-ray collection from two detectors allows the highest X-ray intensity yet recorded to be collected from the NIST Cr thin film. The measured P/B of 6300 is the highest level recorded for an AEM. In addition to collected X-ray intensity (cps/nA) and P/B measured on the standard Cr film, the product of these can be used as a figure-of-merit to evaluate instruments. Estimated minimum mass fraction (MMF) for Cr measured on the standard NIST Cr thin film is also proposed as a figure-of-merit for comparing X-ray detection in AEMs. Determinations here of the MMF of Cr detectable show at least a threefold improvement over previous instruments.

  13. Learning Change from Synthetic Aperture Radar Images: Performance Evaluation of a Support Vector Machine to Detect Earthquake and Tsunami-Induced Changes

    Directory of Open Access Journals (Sweden)

    Marc Wieland

    2016-09-01

    Full Text Available This study evaluates the performance of a Support Vector Machine (SVM classifier to learn and detect changes in single- and multi-temporal X- and L-band Synthetic Aperture Radar (SAR images under varying conditions. The purpose is to provide guidance on how to train a powerful learning machine for change detection in SAR images and to contribute to a better understanding of potentials and limitations of supervised change detection approaches. This becomes particularly important on the background of a rapidly growing demand for SAR change detection to support rapid situation awareness in case of natural disasters. The application environment of this study thus focuses on detecting changes caused by the 2011 Tohoku earthquake and tsunami disaster, where single polarized TerraSAR-X and ALOS PALSAR intensity images are used as input. An unprecedented reference dataset of more than 18,000 buildings that have been visually inspected by local authorities for damages after the disaster forms a solid statistical population for the performance experiments. Several critical choices commonly made during the training stage of a learning machine are being assessed for their influence on the change detection performance, including sampling approach, location and number of training samples, classification scheme, change feature space and the acquisition dates of the satellite images. Furthermore, the proposed machine learning approach is compared with the widely used change image thresholding. The study concludes that a well-trained and tuned SVM can provide highly accurate change detections that outperform change image thresholding. While good performance is achieved in the binary change detection case, a distinction between multiple change classes in terms of damage grades leads to poor performance in the tested experimental setting. The major drawback of a machine learning approach is related to the high costs of training. The outcomes of this study, however

  14. Bleeding rates necessary for detecting acute gastrointestinal bleeding with technetium-99m-labeled red blood cells in an experimental model

    International Nuclear Information System (INIS)

    Thorne, D.A.; Datz, F.L.; Remley, K.; Christian, P.E.

    1987-01-01

    Proponents of [/sup 99m/Tc]sulfur colloid for GI bleeding studies argue that, although labeled red blood cells are useful for intermittent bleeding, they are not capable of detecting low bleeding rates. Studies of dogs with experimental GI bleeding have indicated bleeding rates of 0.05 ml/min can be detected with [/sup 99m/Tc]sulfur colloid. Since similar data in the dog model were unavailable for /sup 99m/Tc-labeled red blood cells, we undertook this study. To simulate lower GI bleeding, catheters were inserted into the bowel lumen. Each dog's blood was labeled with /sup 99m/Tc using an in vitro technique. Venous blood was then withdrawn and re-infused into the lumen of the bowel using a Harvard pump. Fourteen dogs were studied, ten receiving a bleeding rate from 4.6-0.02 ml/min in the descending colon and four with proximal jejunal bleeds of 0.20-0.02 ml/min. Bleeding rates of 4.6-0.2 ml/min were detected within 10 min in the colon and bleeding rates as low as 0.04 ml/min were seen by 55 min. Slower bleeding rates were not detected. Similar findings were noted for proximal jejunal bleeds. Based on the time of appearance, a minimum volume of approximately 2-3 ml labeled blood was necessary to detect bleeding. We conclude that /sup 99m/Tc-labeled RBCs are sensitive for low bleeding rates in the dog model. The rates are comparable to those described for [/sup 99m/Tc]sulfur colloid in this experimental setting. The time of appearance of activity is related to the bleeding rate

  15. Evaluating the Impact of Prescription Fill Rates on Risk Stratification Model Performance.

    Science.gov (United States)

    Chang, Hsien-Yen; Richards, Thomas M; Shermock, Kenneth M; Elder Dalpoas, Stacy; J Kan, Hong; Alexander, G Caleb; Weiner, Jonathan P; Kharrazi, Hadi

    2017-12-01

    Risk adjustment models are traditionally derived from administrative claims. Prescription fill rates-extracted by comparing electronic health record prescriptions and pharmacy claims fills-represent a novel measure of medication adherence and may improve the performance of risk adjustment models. We evaluated the impact of prescription fill rates on claims-based risk adjustment models in predicting both concurrent and prospective costs and utilization. We conducted a retrospective cohort study of 43,097 primary care patients from HealthPartners network between 2011 and 2012. Diagnosis and/or pharmacy claims of 2011 were used to build 3 base models using the Johns Hopkins ACG system, in addition to demographics. Model performances were compared before and after adding 3 types of prescription fill rates: primary 0-7 days, primary 0-30 days, and overall. Overall fill rates utilized all ordered prescriptions from electronic health record while primary fill rates excluded refill orders. The overall, primary 0-7, and 0-30 days fill rates were 72.30%, 59.82%, and 67.33%. The fill rates were similar between sexes but varied across different medication classifications, whereas the youngest had the highest rate. Adding fill rates modestly improved the performance of all models in explaining medical costs (improving concurrent R by 1.15% to 2.07%), followed by total costs (0.58% to 1.43%), and pharmacy costs (0.07% to 0.65%). The impact was greater for concurrent costs compared with prospective costs. Base models without diagnosis information showed the highest improvement using prescription fill rates. Prescription fill rates can modestly enhance claims-based risk prediction models; however, population-level improvements in predicting utilization are limited.

  16. Automatic optimisation of gamma dose rate sensor networks: The DETECT Optimisation Tool

    DEFF Research Database (Denmark)

    Helle, K.B.; Müller, T.O.; Astrup, Poul

    2014-01-01

    of the EU FP 7 project DETECT. It evaluates the gamma dose rates that a proposed set of sensors might measure in an emergency and uses this information to optimise the sensor locations. The gamma dose rates are taken from a comprehensive library of simulations of atmospheric radioactive plumes from 64......Fast delivery of comprehensive information on the radiological situation is essential for decision-making in nuclear emergencies. Most national radiological agencies in Europe employ gamma dose rate sensor networks to monitor radioactive pollution of the atmosphere. Sensor locations were often...... source locations. These simulations cover the whole European Union, so the DOT allows evaluation and optimisation of sensor networks for all EU countries, as well as evaluation of fencing sensors around possible sources. Users can choose from seven cost functions to evaluate the capability of a given...

  17. Value of systematic intervention for chronic obstructive pulmonary disease in a regional Japanese city based on case detection rate and medical cost

    Directory of Open Access Journals (Sweden)

    Tawara Y

    2015-08-01

    Full Text Available Yuichi Tawara,1 Hideaki Senjyu,1 Kenichiro Tanaka,1 Takako Tanaka,1 Masaharu Asai,1 Ryo Kozu,2 Mitsuru Tabusadani,3 Sumihisa Honda,1 Terumitsu Sawai1 1Department of Cardiopulmonary Rehabilitation Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; 2Department of Rehabilitation Medicine, Nagasaki University Hospital, Nagasaki, Japan; 3Center for Industry, University and Government Cooperation, Nagasaki University, Nagasaki, Japan Objective: We established a COPD taskforce for early detection, diagnosis, treatment, and intervention. We implemented a pilot intervention with a prospective and longitudinal design in a regional city. This study evaluates the usefulness of the COPD taskforce and intervention based on COPD case detection rate and per capita medical costs.Method: We distributed a questionnaire to all 8,878 inhabitants aged 50–89 years, resident in Matsuura, Nagasaki Prefecture in 2006. Potentially COPD-positive persons received a pulmonary function test and diagnosis. We implemented ongoing detection, examination, education, and treatment interventions, performed follow-up examinations or respiratory lessons yearly, and supported the health maintenance of each patient. We compared COPD medical costs in Matsuura and in the rest of Nagasaki Prefecture using data from 2004 to 2013 recorded by the association of Nagasaki National Health Insurance Organization, assessing 10-year means and annual change.Results: As of 2014, 256 people have received a definitive diagnosis of COPD; representing 31% of the estimated total number of COPD patients. Of the cases detected, 87.5% were mild or moderate in severity. COPD medical costs per patient in Matsuura were significantly lower than the rest of Nagasaki Prefecture, as was rate of increase in cost over time.Conclusion: The COPD program in Matsuura enabled early detection and treatment of COPD patients and helped to lower the associated burden of medical costs. The

  18. High detection rate of dog circovirus in diarrheal dogs.

    Science.gov (United States)

    Hsu, Han-Siang; Lin, Ting-Han; Wu, Hung-Yi; Lin, Lee-Shuan; Chung, Cheng-Shu; Chiou, Ming-Tang; Lin, Chao-Nan

    2016-06-17

    Diarrhea is one of the most common clinical symptoms reported in companion animal clinics. Dog circovirus (DogCV) is a new mammalian circovirus that is considered to be a cause of alimentary syndromes such as diarrhea, vomiting and hemorrhagic enteritis. DogCV has previously only been identified in the United States, Italy, Germany (GeneBank accession number: KF887949) and China (GeneBank accession number: KT946839). Therefore, the aims of this study were to determine the prevalence of DogCV in Taiwan and to explore the correlation between diarrhea and DogCV infection. Clinical specimens were collected between 2012 and 2014 from 207 dogs suffering from diarrhea and 160 healthy dogs. In this study, we developed a sensitive and specific SYBR Green-based real-time PCR assays to detected DogCV in naturally infected animals. Of the analyzed fecal samples from diarrheal dogs and health dogs, 58 (28.0 %) and 19 (11.9 %), respectively, were DogCV positive. The difference in DogCV prevalence was highly significant (P = 0.0002755) in diarrheal dogs. This is the first study to reveal that DogCV is currently circulating in domestic dogs in Taiwan and to demonstrate its high detection rate in dogs with diarrhea.

  19. Structure and performance of a real-time algorithm to detect tsunami or tsunami-like alert conditions based on sea-level records analysis

    Directory of Open Access Journals (Sweden)

    L. Bressan

    2011-05-01

    Full Text Available The goal of this paper is to present an original real-time algorithm devised for detection of tsunami or tsunami-like waves we call TEDA (Tsunami Early Detection Algorithm, and to introduce a methodology to evaluate its performance. TEDA works on the sea level records of a single station and implements two distinct modules running concurrently: one to assess the presence of tsunami waves ("tsunami detection" and the other to identify high-amplitude long waves ("secure detection". Both detection methods are based on continuously updated time functions depending on a number of parameters that can be varied according to the application. In order to select the most adequate parameter setting for a given station, a methodology to evaluate TEDA performance has been devised, that is based on a number of indicators and that is simple to use. In this paper an example of TEDA application is given by using data from a tide gauge located at the Adak Island in Alaska, USA, that resulted in being quite suitable since it recorded several tsunamis in the last years using the sampling rate of 1 min.

  20. Effect of radiologists' diagnostic work-up volume on interpretive performance.

    Science.gov (United States)

    Buist, Diana S M; Anderson, Melissa L; Smith, Robert A; Carney, Patricia A; Miglioretti, Diana L; Monsees, Barbara S; Sickles, Edward A; Taplin, Stephen H; Geller, Berta M; Yankaskas, Bonnie C; Onega, Tracy L

    2014-11-01

    To examine radiologists' screening performance in relation to the number of diagnostic work-ups performed after abnormal findings are discovered at screening mammography by the same radiologist or by different radiologists. In an institutional review board-approved HIPAA-compliant study, the authors linked 651 671 screening mammograms interpreted from 2002 to 2006 by 96 radiologists in the Breast Cancer Surveillance Consortium to cancer registries (standard of reference) to evaluate the performance of screening mammography (sensitivity, false-positive rate [ FPR false-positive rate ], and cancer detection rate [ CDR cancer detection rate ]). Logistic regression was used to assess the association between the volume of recalled screening mammograms ("own" mammograms, where the radiologist who interpreted the diagnostic image was the same radiologist who had interpreted the screening image, and "any" mammograms, where the radiologist who interpreted the diagnostic image may or may not have been the radiologist who interpreted the screening image) and screening performance and whether the association between total annual volume and performance differed according to the volume of diagnostic work-up. Annually, 38% of radiologists performed the diagnostic work-up for 25 or fewer of their own recalled screening mammograms, 24% performed the work-up for 0-50, and 39% performed the work-up for more than 50. For the work-up of recalled screening mammograms from any radiologist, 24% of radiologists performed the work-up for 0-50 mammograms, 32% performed the work-up for 51-125, and 44% performed the work-up for more than 125. With increasing numbers of radiologist work-ups for their own recalled mammograms, the sensitivity (P = .039), FPR false-positive rate (P = .004), and CDR cancer detection rate (P women recalled per cancer detected from 17.4 for 25 or fewer mammograms to 24.6 for more than 50 mammograms. Increases in work-ups for any radiologist yielded significant

  1. Radon detection system, design, test and performance

    International Nuclear Information System (INIS)

    Balcazar, M.; Chavez, A.; Pina-Villalpando, G.; Navarrete, M.

    1999-01-01

    A portable radon detection system (α-Inin) has been designed and constructed for using it in adverse environmental conditions where humidity, temperature and chemical vaporous are present. The minimum integration time is in periods of 15 min during 41 days. A 12 V battery and a photovoltaic module allow the α-Inin autonomy in field measurements. Data is collected by means of a laptop computer where data processing and α-Inin programming are carried out. α-Inin performance was simultaneously tested in a controlled radon chamber, together with a commercial α-Meter

  2. Computer-aided detection of pulmonary embolism at CT pulmonary angiography: can it improve performance of inexperienced readers?

    International Nuclear Information System (INIS)

    Blackmon, Kevin N.; McCain, Joshua W.; Koonce, James D.; Costello, Philip; Florin, Charles; Bogoni, Luca; Salganicoff, Marcos; Lee, Heon; Bastarrika, Gorka; Thilo, Christian; Joseph Schoepf, U.

    2011-01-01

    To evaluate the effect of a computer-aided detection (CAD) algorithm on the performance of novice readers for detection of pulmonary embolism (PE) at CT pulmonary angiography (CTPA). We included CTPA examinations of 79 patients (50 female, 52 ± 18 years). Studies were evaluated by two independent inexperienced readers who marked all vessels containing PE. After 3 months all studies were reevaluated by the same two readers, this time aided by CAD prototype. A consensus read by three expert radiologists served as the reference standard. Statistical analysis used χ 2 and McNemar testing. Expert consensus revealed 119 PEs in 32 studies. For PE detection, the sensitivity of CAD alone was 78%. Inexperienced readers' initial interpretations had an average per-PE sensitivity of 50%, which improved to 71% (p < 0.001) with CAD as a second reader. False positives increased from 0.18 to 0.25 per study (p = 0.03). Per-study, the readers initially detected 27/32 positive studies (84%); with CAD this number increased to 29.5 studies (92%; p = 0.125). Our results suggest that CAD significantly improves the sensitivity of PE detection for inexperienced readers with a small but appreciable increase in the rate of false positives. (orig.)

  3. Computer-aided detection of pulmonary embolism at CT pulmonary angiography: can it improve performance of inexperienced readers?

    Energy Technology Data Exchange (ETDEWEB)

    Blackmon, Kevin N.; McCain, Joshua W.; Koonce, James D.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Florin, Charles; Bogoni, Luca; Salganicoff, Marcos [Siemens AG, H IM SYNGO CAD Research and Development, Malvern, PA (United States); Lee, Heon [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Seoul Medical Center, Department of Radiology, Seoul (Korea, Republic of); Bastarrika, Gorka [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Navarra, Department of Radiology, Pamplona (Spain); Thilo, Christian; Joseph Schoepf, U. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States)

    2011-06-15

    To evaluate the effect of a computer-aided detection (CAD) algorithm on the performance of novice readers for detection of pulmonary embolism (PE) at CT pulmonary angiography (CTPA). We included CTPA examinations of 79 patients (50 female, 52 {+-} 18 years). Studies were evaluated by two independent inexperienced readers who marked all vessels containing PE. After 3 months all studies were reevaluated by the same two readers, this time aided by CAD prototype. A consensus read by three expert radiologists served as the reference standard. Statistical analysis used {chi}{sup 2} and McNemar testing. Expert consensus revealed 119 PEs in 32 studies. For PE detection, the sensitivity of CAD alone was 78%. Inexperienced readers' initial interpretations had an average per-PE sensitivity of 50%, which improved to 71% (p < 0.001) with CAD as a second reader. False positives increased from 0.18 to 0.25 per study (p = 0.03). Per-study, the readers initially detected 27/32 positive studies (84%); with CAD this number increased to 29.5 studies (92%; p = 0.125). Our results suggest that CAD significantly improves the sensitivity of PE detection for inexperienced readers with a small but appreciable increase in the rate of false positives. (orig.)

  4. A low-volume polyethylene glycol solution was associated with an increased suboptimal bowel preparation rate but had similar recommendations for an early repeat colonoscopy, procedure times, and adenoma detection rates.

    Directory of Open Access Journals (Sweden)

    Sam C Hankins

    Full Text Available Low-volume polyethylene glycol (PEG bowel preparations are better tolerated by patients than high-volume preparations and may achieve similar preparation quality. However, there is little data comparing their effects on a recommendation for an early repeat colonoscopy (because of a suboptimal preparation, procedure times, adenoma detection rate (ADR, and advanced adenoma detection rate (AADR.This is a retrospective cohort study of outpatient colonoscopies performed during a one-year period at a single academic medical center in which low-volume MoviPrep® (n = 1841 or high-volume Colyte® (n = 1337 was used. All preparations were split-dosed. Appropriate covariates were included in regression models assessing suboptimal preparation quality (fair, poor, or inadequate, procedure times, recommendation for an early repeat colonoscopy, ADR, and AADR.MoviPrep® was associated with an increase in having a suboptimal bowel preparation (OR 1.36; 95% CI: 1.06-1.76, but it was not associated with differences in insertion (p = 0.43, withdrawal (p = 0.22, or total procedure times (p = 0.10. The adjusted percentage with a suboptimal preparation was 11.7% for patients using MoviPrep® and 8.8% for patients using Colyte®. MoviPrep® was not associated with a significant difference in overall ADR (OR 0.93; 95% CI: 0.78-1.11, AADR (OR 1.18; 95% CI: 0.87-1.62, or recommendation for early repeat colonoscopy (OR 1.16; 95% CI: 0.72-1.88.MoviPrep® was associated with a small absolute increase in having a suboptimal preparation, but did not affect recommendations for an early repeat colonoscopy, procedure times, or adenoma detection rates. Mechanisms to reduce financial barriers limiting low-volume preparations should be considered because of their favorable tolerability profile.

  5. [Performance based regulation: a strategy to increase breastfeeding rates].

    Science.gov (United States)

    Cobo-Armijo, Fernanda; Charvel, Sofía; Hernández-Ávila, Mauricio

    2017-01-01

    The decreasing breastfeeding rate in México is of public health concern. In this paper we discus an innovative regulatory approach -Performance Based Regulation- and its application to improve breastfeeding rates. This approach, forces industry to take responsibility for the lack of breastfeeding and its consequences. Failure to comply with this targets results in financial penalties. Applying performance based regulation as a strategy to improve breastfeeding is feasible because: the breastmilk substitutes market is an oligopoly, hence it is easy to identify the contribution of each market participant; the regulation's target population is clearly defined; it has a clear regulatory standard which can be easily evaluated, and sanctions to infringement can be defined under objective parameters. modify public policy, celebrate concertation agreements with the industry, create persuasive sanctions, strengthen enforcement activities and coordinate every action with the International Code of Marketing of Breast-milk Substitutes.

  6. Hospital Evaluations by Social Media: A Comparative Analysis of Facebook Ratings among Performance Outliers.

    Science.gov (United States)

    Glover, McKinley; Khalilzadeh, Omid; Choy, Garry; Prabhakar, Anand M; Pandharipande, Pari V; Gazelle, G Scott

    2015-10-01

    An increasing number of hospitals and health systems utilize social media to allow users to provide feedback and ratings. The correlation between ratings on social media and more conventional hospital quality metrics remains largely unclear, raising concern that healthcare consumers may make decisions on inaccurate or inappropriate information regarding quality. The purpose of this study was to examine the extent to which hospitals utilize social media and whether user-generated metrics on Facebook(®) correlate with a Hospital Compare(®) metric, specifically 30-day all cause unplanned hospital readmission rates. This was a retrospective cross-sectional study conducted among all U.S. hospitals performing outside the confidence interval for the national average on 30-day hospital readmission rates as reported on Hospital Compare. Participants were 315 hospitals performing better than U.S. national rate on 30-day readmissions and 364 hospitals performing worse than the U.S. national rate. The study analyzed ratings of hospitals on Facebook's five-star rating scale, 30-day readmission rates, and hospital characteristics including beds, teaching status, urban vs. rural location, and ownership type. Hospitals performing better than the national average on 30-day readmissions were more likely to use Facebook than lower-performing hospitals (93.3 % vs. 83.5 %; p Facebook rating was associated with increased odds of the hospital belonging to the low readmission rate group by a factor of 5.0 (CI: 2.6-10.3, p Facebook-related variables. Hospitals with lower rates of 30-day hospital-wide unplanned readmissions have higher ratings on Facebook than hospitals with higher readmission rates. These findings add strength to the concept that aggregate measures of patient satisfaction on social media correlate with more traditionally accepted measures of hospital quality.

  7. What Does Eye-Blink Rate Variability Dynamics Tell Us About Cognitive Performance?

    Directory of Open Access Journals (Sweden)

    Rafal Paprocki

    2017-12-01

    Full Text Available Cognitive performance is defined as the ability to utilize knowledge, attention, memory, and working memory. In this study, we briefly discuss various markers that have been proposed to predict cognitive performance. Next, we develop a novel approach to characterize cognitive performance by analyzing eye-blink rate variability dynamics. Our findings are based on a sample of 24 subjects. The subjects were given a 5-min resting period prior to a 10-min IQ test. During both stages, eye blinks were recorded from Fp1 and Fp2 electrodes. We found that scale exponents estimated for blink rate variability during rest were correlated with subjects' performance on the subsequent IQ test. This surprising phenomenon could be explained by the person to person variation in concentrations of dopamine in PFC and accumulation of GABA in the visual cortex, as both neurotransmitters play a key role in cognitive processes and affect blinking. This study demonstrates the possibility that blink rate variability dynamics at rest carry information about cognitive performance and can be employed in the assessment of cognitive abilities without taking a test.

  8. High-Rate Performance of Muon Drift Tube Detectors

    CERN Document Server

    Schwegler, Philipp

    The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are stud...

  9. Performance of computer-aided detection applied to full-field digital mammography in detection of breast cancers

    International Nuclear Information System (INIS)

    Sadaf, Arifa; Crystal, Pavel; Scaranelo, Anabel; Helbich, Thomas

    2011-01-01

    Objective: The aim of this retrospective study was to evaluate performance of computer-aided detection (CAD) with full-field digital mammography (FFDM) in detection of breast cancers. Materials and Methods: CAD was retrospectively applied to standard mammographic views of 127 cases with biopsy proven breast cancers detected with FFDM (Senographe 2000, GE Medical Systems). CAD sensitivity was assessed in total group of 127 cases and for subgroups based on breast density, mammographic lesion type, mammographic lesion size, histopathology and mode of presentation. Results: Overall CAD sensitivity was 91% (115 of 127 cases). There were no statistical differences (p > 0.1) in CAD detection of cancers in dense breasts 90% (53/59) versus non-dense breasts 91% (62/68). There was statistical difference (p 20 mm 97% (22/23). Conclusion: CAD applied to FFDM showed 100% sensitivity in identifying cancers manifesting as microcalcifications only and high sensitivity 86% (71/83) for other mammographic appearances of cancer. Sensitivity is influenced by lesion size. CAD in FFDM is an adjunct helping radiologist in early detection of breast cancers.

  10. Performance of mitochondrial DNA mutations detecting early stage cancer

    International Nuclear Information System (INIS)

    Jakupciak, John P; Srivastava, Sudhir; Sidransky, David; O'Connell, Catherine D; Maragh, Samantha; Markowitz, Maura E; Greenberg, Alissa K; Hoque, Mohammad O; Maitra, Anirban; Barker, Peter E; Wagner, Paul D; Rom, William N

    2008-01-01

    Mutations in the mitochondrial genome (mtgenome) have been associated with cancer and many other disorders. These mutations can be point mutations or deletions, or admixtures (heteroplasmy). The detection of mtDNA mutations in body fluids using resequencing microarrays, which are more sensitive than other sequencing methods, could provide a strategy to measure mutation loads in remote anatomical sites. We determined the mtDNA mutation load in the entire mitochondrial genome of 26 individuals with different early stage cancers (lung, bladder, kidney) and 12 heavy smokers without cancer. MtDNA was sequenced from three matched specimens (blood, tumor and body fluid) from each cancer patient and two matched specimens (blood and sputum) from smokers without cancer. The inherited wildtype sequence in the blood was compared to the sequences present in the tumor and body fluid, detected using the Affymetrix Genechip ® Human Mitochondrial Resequencing Array 1.0 and supplemented by capillary sequencing for noncoding region. Using this high-throughput method, 75% of the tumors were found to contain mtDNA mutations, higher than in our previous studies, and 36% of the body fluids from these cancer patients contained mtDNA mutations. Most of the mutations detected were heteroplasmic. A statistically significantly higher heteroplasmy rate occurred in tumor specimens when compared to both body fluid of cancer patients and sputum of controls, and in patient blood compared to blood of controls. Only 2 of the 12 sputum specimens from heavy smokers without cancer (17%) contained mtDNA mutations. Although patient mutations were spread throughout the mtDNA genome in the lung, bladder and kidney series, a statistically significant elevation of tRNA and ND complex mutations was detected in tumors. Our findings indicate comprehensive mtDNA resequencing can be a high-throughput tool for detecting mutations in clinical samples with potential applications for cancer detection, but it is

  11. Effect of exposure to good vs poor medical trainee performance on attending physician ratings of subsequent performances.

    Science.gov (United States)

    Yeates, Peter; O'Neill, Paul; Mann, Karen; Eva, Kevin W

    2012-12-05

    Competency-based models of education require assessments to be based on individuals' capacity to perform, yet the nature of human judgment may fundamentally limit the extent to which such assessment is accurately possible. To determine whether recent observations of the Mini Clinical Evaluation Exercise (Mini-CEX) performance of postgraduate year 1 physicians influence raters' scores of subsequent performances, consistent with either anchoring bias (scores biased similar to previous experience) or contrast bias (scores biased away from previous experience). Internet-based randomized, blinded experiment using videos of Mini-CEX assessments of postgraduate year 1 trainees interviewing new internal medicine patients. Participants were 41 attending physicians from England and Wales experienced with the Mini-CEX, with 20 watching and scoring 3 good trainee performances and 21 watching and scoring 3 poor performances. All then watched and scored the same 3 borderline video performances. The study was completed between July and November 2011. The primary outcome was scores assigned to the borderline videos, using a 6-point Likert scale (anchors included: 1, well below expectations; 3, borderline; 6, well above expectations). Associations were tested in a multivariable analysis that included participants' sex, years of practice, and the stringency index (within-group z score of initial 3 ratings). The mean rating scores assigned by physicians who viewed borderline video performances following exposure to good performances was 2.7 (95% CI, 2.4-3.0) vs 3.4 (95% CI, 3.1-3.7) following exposure to poor performances (difference of 0.67 [95% CI, 0.28-1.07]; P = .001). Borderline videos were categorized as consistent with failing scores in 33 of 60 assessments (55%) in those exposed to good performances and in 15 of 63 assessments (24%) in those exposed to poor performances (P performances compared with 25 of 63 assessments (39.5%) in those exposed to poor performances (P poor

  12. Accurate mobile malware detection and classification in the cloud.

    Science.gov (United States)

    Wang, Xiaolei; Yang, Yuexiang; Zeng, Yingzhi

    2015-01-01

    As the dominator of the Smartphone operating system market, consequently android has attracted the attention of s malware authors and researcher alike. The number of types of android malware is increasing rapidly regardless of the considerable number of proposed malware analysis systems. In this paper, by taking advantages of low false-positive rate of misuse detection and the ability of anomaly detection to detect zero-day malware, we propose a novel hybrid detection system based on a new open-source framework CuckooDroid, which enables the use of Cuckoo Sandbox's features to analyze Android malware through dynamic and static analysis. Our proposed system mainly consists of two parts: anomaly detection engine performing abnormal apps detection through dynamic analysis; signature detection engine performing known malware detection and classification with the combination of static and dynamic analysis. We evaluate our system using 5560 malware samples and 6000 benign samples. Experiments show that our anomaly detection engine with dynamic analysis is capable of detecting zero-day malware with a low false negative rate (1.16 %) and acceptable false positive rate (1.30 %); it is worth noting that our signature detection engine with hybrid analysis can accurately classify malware samples with an average positive rate 98.94 %. Considering the intensive computing resources required by the static and dynamic analysis, our proposed detection system should be deployed off-device, such as in the Cloud. The app store markets and the ordinary users can access our detection system for malware detection through cloud service.

  13. Early detection of pharmacovigilance signals with automated methods based on false discovery rates: a comparative study.

    Science.gov (United States)

    Ahmed, Ismaïl; Thiessard, Frantz; Miremont-Salamé, Ghada; Haramburu, Françoise; Kreft-Jais, Carmen; Bégaud, Bernard; Tubert-Bitter, Pascale

    2012-06-01

    Improving the detection of drug safety signals has led several pharmacovigilance regulatory agencies to incorporate automated quantitative methods into their spontaneous reporting management systems. The three largest worldwide pharmacovigilance databases are routinely screened by the lower bound of the 95% confidence interval of proportional reporting ratio (PRR₀₂.₅), the 2.5% quantile of the Information Component (IC₀₂.₅) or the 5% quantile of the Gamma Poisson Shrinker (GPS₀₅). More recently, Bayesian and non-Bayesian False Discovery Rate (FDR)-based methods were proposed that address the arbitrariness of thresholds and allow for a built-in estimate of the FDR. These methods were also shown through simulation studies to be interesting alternatives to the currently used methods. The objective of this work was twofold. Based on an extensive retrospective study, we compared PRR₀₂.₅, GPS₀₅ and IC₀₂.₅ with two FDR-based methods derived from the Fisher's exact test and the GPS model (GPS(pH0) [posterior probability of the null hypothesis H₀ calculated from the Gamma Poisson Shrinker model]). Secondly, restricting the analysis to GPS(pH0), we aimed to evaluate the added value of using automated signal detection tools compared with 'traditional' methods, i.e. non-automated surveillance operated by pharmacovigilance experts. The analysis was performed sequentially, i.e. every month, and retrospectively on the whole French pharmacovigilance database over the period 1 January 1996-1 July 2002. Evaluation was based on a list of 243 reference signals (RSs) corresponding to investigations launched by the French Pharmacovigilance Technical Committee (PhVTC) during the same period. The comparison of detection methods was made on the basis of the number of RSs detected as well as the time to detection. Results comparing the five automated quantitative methods were in favour of GPS(pH0) in terms of both number of detections of true signals and

  14. Initial Progress Rates as Related to Performance in a Personalized System of Instruction

    Science.gov (United States)

    Henneberry, John K.

    1976-01-01

    Discusses research which explored the hypothesis that students who are fast starters in a personalized system of instruction psychology course would perform better and maintain faster course progress rates than slow starters. Findings indicate that students' starting pace is predictive of course performance and subsequent progress rates.…

  15. A new rate-dependent model for high-frequency tracking performance enhancement of piezoactuator system

    Science.gov (United States)

    Tian, Lizhi; Xiong, Zhenhua; Wu, Jianhua; Ding, Han

    2017-05-01

    Feedforward-feedback control is widely used in motion control of piezoactuator systems. Due to the phase lag caused by incomplete dynamics compensation, the performance of the composite controller is greatly limited at high frequency. This paper proposes a new rate-dependent model to improve the high-frequency tracking performance by reducing dynamics compensation error. The rate-dependent model is designed as a function of the input and input variation rate to describe the input-output relationship of the residual system dynamics which mainly performs as phase lag in a wide frequency band. Then the direct inversion of the proposed rate-dependent model is used to compensate the residual system dynamics. Using the proposed rate-dependent model as feedforward term, the open loop performance can be improved significantly at medium-high frequency. Then, combining the with feedback controller, the composite controller can provide enhanced close loop performance from low frequency to high frequency. At the frequency of 1 Hz, the proposed controller presents the same performance as previous methods. However, at the frequency of 900 Hz, the tracking error is reduced to be 30.7% of the decoupled approach.

  16. Performance based regulation: a strategy to increase breastfeeding rates

    Directory of Open Access Journals (Sweden)

    Fernanda Cobo-Armijo

    2017-05-01

    Full Text Available The decreasing breastfeeding rate in México is of public health concern. In this paper we discus an innovative regulatory ap­proach -Performance Based Regulation- and its application to improve breastfeeding rates. This approach, forces industry to take responsibility for the lack of breastfeeding and its consequences. Failure to comply with this targets results in financial penalties. Applying performance based regulation as a strategy to improve breastfeeding is feasible because: the breastmilk substitutes market is an oligopoly, hence it is easy to identify the contribution of each market participant; the regulation’s target population is clearly defined; it has a clear regulatory standard which can be easily evaluated, and sanctions to infringement can be defined under objective parameters. Recommendations: modify public policy, celebrate concertation agreements with the industry, create persuasive sanctions, strengthen enforcement activities and coordinate every action with the International Code of Marketing of Breast-milk Substitutes.

  17. Achievable Performance of Zero-Delay Variable-Rate Coding in Rate-Constrained Networked Control Systems with Channel Delay

    DEFF Research Database (Denmark)

    Barforooshan, Mohsen; Østergaard, Jan; Stavrou, Fotios

    2017-01-01

    This paper presents an upper bound on the minimum data rate required to achieve a prescribed closed-loop performance level in networked control systems (NCSs). The considered feedback loop includes a linear time-invariant (LTI) plant with single measurement output and single control input. Moreover......, in this NCS, a causal but otherwise unconstrained feedback system carries out zero-delay variable-rate coding, and control. Between the encoder and decoder, data is exchanged over a rate-limited noiseless digital channel with a known constant time delay. Here we propose a linear source-coding scheme...

  18. Endoscopic detection rate of sessile serrated lesions in Lynch syndrome patients is comparable with an age- and gender-matched control population: case-control study with expert pathology review.

    Science.gov (United States)

    Vleugels, Jasper L A; Sahin, Husna; Hazewinkel, Yark; Koens, Lianne; van den Berg, Jose G; van Leerdam, Monique E; Dekker, Evelien

    2018-05-01

    Carcinogenesis in Lynch syndrome involves fast progression of adenomas to colorectal cancer (CRC) because of microsatellite instability. The role of sessile serrated lesions (SSLs) and the serrated neoplasia pathway in these patients is unknown. The aim of this matched case-control study was to compare endoscopic detection rates and distribution of SSLs in Lynch syndrome patients with a matched control population. We collected data of Lynch syndrome patients with a proven germline mutation who underwent colonoscopy between January 2011 and April 2016 in 2 tertiary referral hospitals. Control subjects undergoing elective colonoscopy from 2011 and onward for symptoms or surveillance were selected from a prospectively collected database. Patients were matched 1:1 for age, gender, and index versus surveillance colonoscopy. An expert pathology review of serrated polyps was performed. The primary outcomes included the detection rates and distribution of SSLs. We identified 321 patients with Lynch syndrome who underwent at least 1 colonoscopy. Of these, 223 Lynch syndrome patients (mean age, 49.3; 59% women; index colonoscopy, 56%) were matched to 223 control subjects. SSLs were detected in 7.6% (95% confidence interval, 4.8-11.9) of colonoscopies performed in Lynch syndrome patients and in 6.7% (95% confidence interval, 4.1-10.8) of control subjects (P = .86). None of the detected SSLs in Lynch syndrome patients contained dysplasia. The detection rate of SSLs in Lynch syndrome patients undergoing colonoscopy is comparable with a matched population. These findings suggest that the role of the serrated neoplasia pathway in CRC development in Lynch syndrome seems to be comparable with that in the general population. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  19. Three-minute constant rate step test for detecting exertional dyspnea relief after bronchodilation in COPD

    Directory of Open Access Journals (Sweden)

    Borel B

    2016-11-01

    Full Text Available Benoit Borel,1,2 Courtney A Wilkinson-Maitland,3 Alan Hamilton,4 Jean Bourbeau,5 Hélène Perrault,6 Dennis Jensen,3,5,7 François Maltais2 1Laboratoire HAVAE, Université de Limoges, Limoges, France; 2Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, 3Clinical Exercise and Respiratory Physiology Laboratory, Department of Kinesiology and Physical Education, McGill University, Montréal, QC, 4Boehringer Ingelheim (Canada Limited, Burlington, ON, 5Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, McGill University Health Center, Montreal, QC, 6Faculty of Health Sciences, University of Ottawa, Ottawa, ON, 7Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, QC, Canada Background: The aim of this study was to evaluate the responsiveness of the 3-minute constant rate step test (3-MST to detect the relief of exertional dyspnea (respiratory discomfort after acute bronchodilation in COPD patients. Patients and methods: A total of 40 patients with moderate-to-severe COPD (mean forced expiratory volume in 1 second: 45.7 (±14.7, % predicted performed four 3-MSTs at randomly assigned stepping rates of 14, 16, 20 and 24 steps/min after inhalation of nebulized ipratropium bromide (500 µg/salbutamol (2.5 mg and saline placebo, which were randomized to order. Patients rated their intensity of perceived dyspnea at the end of each 3-MST using Borg 0–10 category ratio scale. Results: A total of 37 (92.5%, 36 (90%, 34 (85% and 27 (67.5% patients completed all 3 minutes of exercise at 14, 16, 20 and 24 steps/min under both treatment conditions, respectively. Compared with placebo, ipratropium bromide/salbutamol significantly decreased dyspnea at the end of the third minute of exercise at 14 steps/min (by 0.6±1.0 Borg 0–10 scale units, P<0.01 and 16 steps/min (by 0.7±1.3 Borg 0–10 scale

  20. Detectability of changes in cosmic-ray counting rate measured with the Liulin detector

    International Nuclear Information System (INIS)

    Malusek, A.; Kubancak, J.; Ambrozova, I.

    2011-05-01

    Experimental data are needed to improve and validate models predicting the dynamics of solar particle events because the mechanisms of processes leading to the acceleration of solar energetic particles are not yet fully understood. The aim of this work was to examine whether the spectrometer of deposited energy, Liulin, positioned at the Lomnický štít mountain observatory can collect such data. Decision thresholds and detection limits for the increase or decrease in the average number of particles detected by Liulin were determined for a period in February 2011. The changes in counts corresponding to the decision thresholds and detection limits relative to the average number of detected particles were about 17% and 33%, respectively. The Forbush decrease with a maximum change of about 6.8%, which started on February 18, was detectable neither during the 10-minute acquisition time nor during any other, longer period. Statistical analysis showed that an acquisition time about 7 hours would be needed to detect a 5% decrease. As this time was shorter than the duration of the Forbush decrease (about 56 hours), we theorize that the current placement of the Liulin detector inside a living room shielded by a thick concrete ceiling may have had an adverse impact on the detectability of the the cosmic ray counting rate decrease. To test this hypothesis, we recommend positioning the Liulin detector outside the main observatory building.. (author)

  1. NPP ATMS Snowfall Rate Product

    Science.gov (United States)

    Meng, Huan; Ferraro, Ralph; Kongoli, Cezar; Wang, Nai-Yu; Dong, Jun; Zavodsky, Bradley; Yan, Banghua

    2015-01-01

    Passive microwave measurements at certain high frequencies are sensitive to the scattering effect of snow particles and can be utilized to retrieve snowfall properties. Some of the microwave sensors with snowfall sensitive channels are Advanced Microwave Sounding Unit (AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the follow-on sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has been developed recently. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. The model employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derive the probability of snowfall (Kongoli et al., 2015). In addition, a set of NWP model based filters is also employed to improve the accuracy of snowfall detection. Cloud properties are retrieved using an inversion method with an iteration algorithm and a two-stream radiative transfer model (Yan et al., 2008). A method developed by Heymsfield and Westbrook (2010) is adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. NCEP CMORPH analysis has shown that integration of ATMS SFR has improved the performance of CMORPH-Snow. The ATMS SFR product is also being assessed at several NWS Weather Forecast Offices for its usefulness in weather forecast.

  2. High-rate performance of muon drift tube detectors

    International Nuclear Information System (INIS)

    Schwegler, Philipp

    2014-01-01

    The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are studied. The resolution and efficiency of sMDT chambers at high γ-ray and proton irradiation rates well beyond the ones expected at HL-LHC have been measured and the irradiation effects understood using detailed simulations. The sMDT chambers offer an about an order of magnitude better rate capability and are an ideal replacement for the MDT chambers because of compatibility of services and read-out. The limitations of the sMDT chambers are now in the read-out electronics, taken from the MDT chambers, to which improvements for even higher rate capability are proposed.

  3. Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

    International Nuclear Information System (INIS)

    Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H.; Asano, T.; Kato, H.; Hoshi, H.; Yamakawa, H.; Iwama, T.; Ando, H.; Yamakawa, H.

    2007-01-01

    The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

  4. Detection and Modeling of Non-Tidal Oceanic Effects on the Earth's Rotation Rate

    Science.gov (United States)

    Marcus, S. L.; Chao, Y.; Dickey, J. O.; Gegout, P.

    1998-01-01

    Sub-decadal changes in the Earth's rotation rate, and hence in the length-of-day (LOD), are largely controlled by variations in atmospheric angular momentum. Results from two oceanic general circulation models (OGCMs), forced by observed wind stress and heat flux for the years 1992-1994, show that ocean current and mass distribution changes also induce detectable LOD variations.

  5. Academic performance and pass rates: Comparison of three first ...

    African Journals Online (AJOL)

    First year students' academic performance in three Life Science courses (Botany, Zoology and Bioscience) was compared. Pass rates, as well as the means and distributions of final marks were analysed. Of the three components (coursework, practical and theory examinations) contributing to the final mark of each course, ...

  6. Transfer Rate Edited experiment for the selective detection of Chemical Exchange via Saturation Transfer (TRE-CEST).

    Science.gov (United States)

    Friedman, Joshua I; Xia, Ding; Regatte, Ravinder R; Jerschow, Alexej

    2015-07-01

    Chemical Exchange Saturation Transfer (CEST) magnetic resonance experiments have become valuable tools in magnetic resonance for the detection of low concentration solutes with far greater sensitivity than direct detection methods. Accurate measures of rates of chemical exchange provided by CEST are of particular interest to biomedical imaging communities where variations in chemical exchange can be related to subtle variations in biomarker concentration, temperature and pH within tissues using MRI. Despite their name, however, traditional CEST methods are not truly selective for chemical exchange and instead detect all forms of magnetization transfer including through-space NOE. This ambiguity crowds CEST spectra and greatly complicates subsequent data analysis. We have developed a Transfer Rate Edited CEST experiment (TRE-CEST) that uses two different types of solute labeling in order to selectively amplify signals of rapidly exchanging proton species while simultaneously suppressing 'slower' NOE-dominated magnetization transfer processes. This approach is demonstrated in the context of both NMR and MRI, where it is used to detect the labile amide protons of proteins undergoing chemical exchange (at rates⩾30s(-1)) while simultaneously eliminating signals originating from slower (∼5s(-1)) NOE-mediated magnetization transfer processes. TRE-CEST greatly expands the utility of CEST experiments in complex systems, and in-vivo, in particular, where it is expected to improve the quantification of chemical exchange and magnetization transfer rates while enabling new forms of imaging contrast. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. MDT Performance in a High Rate Background Environment

    CERN Document Server

    Aleksa, Martin; Hessey, N P; Riegler, W

    1998-01-01

    A Cs137 gamma source with different lead filters in the SPS beam-line X5 has been used to simulate the ATLAS background radiation. This note shows the impact of high background rates on the MDT efficiency and resolution for three kinds of pulse shaping and compares the results with GARFIELD simulations. Furthermore it explains how the performance can be improved by time slewing corrections and double track separation.

  8. Effects of Excerpt Tempo and Duration on Musicians' Ratings of High-Level Piano Performances

    Science.gov (United States)

    Wapnick, Joel; Ryan, Charlene; Campbell, Louise; Deek, Patricia; Lemire, Renata; Darrow, Alice-Ann

    2005-01-01

    The purpose of this study was to determine how judgments of solo performances recorded at an international piano competition might be affected by excerpt duration (20 versus 60 seconds) and tempo (slow versus fast). Musicians rated performances on six test items. Results indicated that piano majors rated slow excerpts higher than they rated fast…

  9. Standard and Nonstandard Neutrino-Nucleus Reactions Cross Sections and Event Rates to Neutrino Detection Experiments

    Directory of Open Access Journals (Sweden)

    D. K. Papoulias

    2015-01-01

    Full Text Available In this work, we explore ν-nucleus processes from a nuclear theory point of view and obtain results with high confidence level based on accurate nuclear structure cross sections calculations. Besides cross sections, the present study includes simulated signals expected to be recorded by nuclear detectors and differential event rates as well as total number of events predicted to be measured. Our original cross sections calculations are focused on measurable rates for the standard model process, but we also perform calculations for various channels of the nonstandard neutrino-nucleus reactions and come out with promising results within the current upper limits of the corresponding exotic parameters. We concentrate on the possibility of detecting (i supernova neutrinos by using massive detectors like those of the GERDA and SuperCDMS dark matter experiments and (ii laboratory neutrinos produced near the spallation neutron source facilities (at Oak Ridge National Lab by the COHERENT experiment. Our nuclear calculations take advantage of the relevant experimental sensitivity and employ the severe bounds extracted for the exotic parameters entering the Lagrangians of various particle physics models and specifically those resulting from the charged lepton flavour violating μ-→e- experiments (Mu2e and COMET experiments.

  10. Energy performance ratings and house prices in Wales: An empirical study

    International Nuclear Information System (INIS)

    Fuerst, Franz; McAllister, Pat; Nanda, Anupam; Wyatt, Pete

    2016-01-01

    This paper investigates the effect of Energy Performance Certificate (EPC) ratings on residential prices in Wales. Drawing on a sample of approximately 192,000 transactions, the capitalisation of energy efficiency ratings into house prices is investigated using two approaches. The first adopts a cross-sectional framework to investigate the effect of EPC rating on price. The second approach applies a repeat-sales methodology to investigate the impact of EPC rating on house price appreciation. Statistically significant positive price premiums are estimated for dwellings in EPC bands A/B (12.8%) and C (3.5%) compared to houses in band D. For dwellings in band E (−3.6%) and F (−6.5%) there are statistically significant discounts. Such effects may not be the result of energy performance alone. In addition to energy cost differences, the price effect may be due to additional benefits of energy efficient features. An analysis of the private rental segment reveals that, in contrast to the general market, low-EPC rated dwellings were not traded at a significant discount. This suggests different implicit prices of potential energy savings for landlords and owner-occupiers.

  11. Lung nodule detection in pediatric chest CT: quantitative relationship between image quality and radiologist performance.

    Science.gov (United States)

    Li, Xiang; Samei, Ehsan; Barnhart, Huiman X; Gaca, Ana Maria; Hollingsworth, Caroline L; Maxfield, Charles M; Carrico, Caroline W T; Colsher, James G; Frush, Donald P

    2011-05-01

    To determine the quantitative relationship between image quality and radiologist performance in detecting small lung nodules in pediatric CT. The study included clinical chest CT images of 30 pediatric patients (0-16 years) scanned at tube currents of 55-180 mA. Calibrated noise addition software was used to simulate cases at three nominal mA settings: 70, 35, and 17.5 mA, resulting in quantum noise of 7-32 Hounsfield Unit (HU). Using a validated nodule simulation technique, lung nodules with diameters of 3-5 mm and peak contrasts of 200-500 HU were inserted into the cases, which were then randomized and rated independently by four experienced pediatric radiologists for nodule presence on a continuous scale from 0 (definitely absent) to 100 (definitely present). The receiver operating characteristic (ROC) data were analyzed to quantify the relationship between diagnostic accuracy (area under the ROC curve, AUC) and image quality (the product of nodule peak contrast and displayed diameter to noise ratio, CDNR display). AUC increased rapidly from 0.70 to 0.87 when CDNR display increased from 60 to 130 mm, followed by a slow increase to 0.94 when CDNR display further increased to 257 mm. For the average nodule diameter (4 mm) and contrast (350 HU), AUC decreased from 0.93 to 0.71 with noise increased from 7 to 28 HU. We quantified the relationship between image quality and the performance of radiologists in detecting lung nodules in pediatric CT. The relationship can guide CT protocol design to achieve the desired diagnostic performance at the lowest radiation dose.

  12. Online physician ratings fail to predict actual performance on measures of quality, value, and peer review.

    Science.gov (United States)

    Daskivich, Timothy J; Houman, Justin; Fuller, Garth; Black, Jeanne T; Kim, Hyung L; Spiegel, Brennan

    2018-04-01

    Patients use online consumer ratings to identify high-performing physicians, but it is unclear if ratings are valid measures of clinical performance. We sought to determine whether online ratings of specialist physicians from 5 platforms predict quality of care, value of care, and peer-assessed physician performance. We conducted an observational study of 78 physicians representing 8 medical and surgical specialties. We assessed the association of consumer ratings with specialty-specific performance scores (metrics including adherence to Choosing Wisely measures, 30-day readmissions, length of stay, and adjusted cost of care), primary care physician peer-review scores, and administrator peer-review scores. Across ratings platforms, multivariable models showed no significant association between mean consumer ratings and specialty-specific performance scores (β-coefficient range, -0.04, 0.04), primary care physician scores (β-coefficient range, -0.01, 0.3), and administrator scores (β-coefficient range, -0.2, 0.1). There was no association between ratings and score subdomains addressing quality or value-based care. Among physicians in the lowest quartile of specialty-specific performance scores, only 5%-32% had consumer ratings in the lowest quartile across platforms. Ratings were consistent across platforms; a physician's score on one platform significantly predicted his/her score on another in 5 of 10 comparisons. Online ratings of specialist physicians do not predict objective measures of quality of care or peer assessment of clinical performance. Scores are consistent across platforms, suggesting that they jointly measure a latent construct that is unrelated to performance. Online consumer ratings should not be used in isolation to select physicians, given their poor association with clinical performance.

  13. Observer performance in detecting multiple radiographic signals: prediction and analysis using a generalized ROC approach

    International Nuclear Information System (INIS)

    Metz, C.E.; Starr, S.J.; Lusted, L.B.

    1975-01-01

    The theories of decision processes and signal detection provide a framework for the evaluation of observer performance. Some radiologic procedures involve a search for multiple similar lesions, as in gallstone or pneumoconiosis examinations. A model is presented which attempts to predict, from the conventional receiver operating characteristic (ROC) curve describing the detectability of a single visual signal in a radiograph, observer performance in an experiment requiring detection of more than one such signal. An experiment is described which tests the validity of this model for the case of detecting the presence of zero, one, or two low-contrast radiographic images of a two-mm.-diameter lucite bead embedded in radiographic mottle. Results from six observers, including three radiologists, confirm the validity of the model and suggest that human observer performance for relatively complex detection tasks can be predicted from the results of simpler experiments

  14. Ligand Binding Site Detection by Local Structure Alignment and Its Performance Complementarity

    Science.gov (United States)

    Lee, Hui Sun; Im, Wonpil

    2013-01-01

    Accurate determination of potential ligand binding sites (BS) is a key step for protein function characterization and structure-based drug design. Despite promising results of template-based BS prediction methods using global structure alignment (GSA), there is a room to improve the performance by properly incorporating local structure alignment (LSA) because BS are local structures and often similar for proteins with dissimilar global folds. We present a template-based ligand BS prediction method using G-LoSA, our LSA tool. A large benchmark set validation shows that G-LoSA predicts drug-like ligands’ positions in single-chain protein targets more precisely than TM-align, a GSA-based method, while the overall success rate of TM-align is better. G-LoSA is particularly efficient for accurate detection of local structures conserved across proteins with diverse global topologies. Recognizing the performance complementarity of G-LoSA to TM-align and a non-template geometry-based method, fpocket, a robust consensus scoring method, CMCS-BSP (Complementary Methods and Consensus Scoring for ligand Binding Site Prediction), is developed and shows improvement on prediction accuracy. The G-LoSA source code is freely available at http://im.bioinformatics.ku.edu/GLoSA. PMID:23957286

  15. Performances of Four Helicobacter pylori Serological Detection Kits Using Stool Antigen Test as Gold Standard.

    Science.gov (United States)

    Biranjia-Hurdoyal, Susheela D; Seetulsingh-Goorah, Sharmila P

    2016-01-01

    The aim was to determine the performances of four Helicobacter pylori serological detection kits in different target groups, using Amplified IDEIA™ Hp StAR™ as gold standard. Kits studied were Rapid Immunochromatoghraphic Hexagon, Helicoblot 2.1, an EIA IgG kit and EIA IgA kit. Stool and blood samples were collected from 162 apparently healthy participants (control) and 60 Type 2 diabetes mellitus (T2DM) patients. The performances of the four serological detection kits were found to be affected by gender, age, health status and ethnicity of the participants. In the control group, the Helicoblot 2.1 kit had the best performance (AUC = 0.85; ppoor performances. In the T2DM subgroup, the kits H2.1 and EIA IgG had best performances, with accuracies of 96.5% and 93.1% respectively. The performance of EIA IgG improved with adjustment of its cut-off value. The performances of the detection kits were affected by various factors which should be taken into consideration.

  16. Diagnostic Performance of CT Colonography for the Detection of Colorectal Polyps

    International Nuclear Information System (INIS)

    Yun, Ji Young; Ro, Hee Jeong; Choi, Jung Bin; Chung, Ji Eun; Kim, Yong Jin; Suh, Won Hyuck; Lee, Jong Kyun; Park, Jong Beom

    2007-01-01

    To investigate the diagnostic value of CT colonography for the detection of colorectal polyps. From December 2004 to December 2005, 399 patients underwent CT colonography and follow-up conventional colonoscopy. We excluded cases of advanced colorectal cancer. We retrospectively analyzed the CT colonography findings and follow-up conventional colonoscopy findings of 113 patients who had polyps more than 6 mm in diameter. Radiologists using 3D and 2D computer generated displays interpreted the CT colonography images. The colonoscopists were aware of the CT colonography findings before the procedure. CT colonography detected 132 polyps in 107 of the 113 patients and conventional colonoscopy detected 114 colorectal polyps more than 6 mm in diameter in 87 of the 113 patients. The sensitivity of CT colonography analyzed per polyp was 91% (41/45) for polyps more than 10 mm in diameter and 89% (101/114) for polyps more than 6 mm in diameter. Thirteen polyps were missed by CT colonography and were detected on follow-up conventional colonoscopy. CT colonography is a sensitive diagnostic tool for the detection of colorectal polyps and adequate bowel preparation, optimal bowel distention and clinical experience are needed to reduce the rate of missing appropriate lesions

  17. The use of quality control performance charts to analyze cesarean delivery rates nationally.

    LENUS (Irish Health Repository)

    Turner, Michael J

    2012-02-01

    OBJECTIVE: To examine the use of quality control performance charts to analyze cesarean rates nationally. METHODS: Information on cesarean rates was obtained for all 19 Irish maternity hospitals receiving state funding in 2009. All women who underwent cesarean delivery of a live or stillborn infant weighing 500 g or more between January 1 and December 31 were included. Deliveries were classified as elective or emergency. Individual hospitals were not identified in the analysis. RESULTS: The mean rates per hospital of elective and emergency cesarean were 12.9+\\/-2.6% (n=9337) and 13.8+\\/-3.0% (n=9989), respectively-giving an overall mean rate of 26.7+\\/-4.2% (n=19326) per hospital. Cesarean rates were normally distributed. Using a quality control performance chart with a cutoff 2 standard deviations from the mean, 1 hospital was above the normal range for both total and elective cesareans, indicating that its pre-labor obstetric practices warrant clinical review. Another hospital had a mean emergency cesarean rate above the normal range, indicating that its labor ward practices warrant review. CONCLUSION: Quality control performance charts can be used to analyze cesarean rates nationally and, thus, to identify hospitals at which obstetric practices should be reviewed.

  18. Low-complexity R-peak detection for ambulatory fetal monitoring

    International Nuclear Information System (INIS)

    Rooijakkers, Michael J; Rabotti, Chiara; Mischi, Massimo; Oei, S Guid

    2012-01-01

    Non-invasive fetal health monitoring during pregnancy is becoming increasingly important because of the increasing number of high-risk pregnancies. Despite recent advances in signal-processing technology, which have enabled fetal monitoring during pregnancy using abdominal electrocardiogram (ECG) recordings, ubiquitous fetal health monitoring is still unfeasible due to the computational complexity of noise-robust solutions. In this paper, an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, without reducing the R-peak detection performance compared to the existing R-peak detection schemes. Validation of the algorithm is performed on three manually annotated datasets. With a detection error rate of 0.23%, 1.32% and 9.42% on the MIT/BIH Arrhythmia and in-house maternal and fetal databases, respectively, the detection rate of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity. (paper)

  19. Low-complexity R-peak detection for ambulatory fetal monitoring.

    Science.gov (United States)

    Rooijakkers, Michael J; Rabotti, Chiara; Oei, S Guid; Mischi, Massimo

    2012-07-01

    Non-invasive fetal health monitoring during pregnancy is becoming increasingly important because of the increasing number of high-risk pregnancies. Despite recent advances in signal-processing technology, which have enabled fetal monitoring during pregnancy using abdominal electrocardiogram (ECG) recordings, ubiquitous fetal health monitoring is still unfeasible due to the computational complexity of noise-robust solutions. In this paper, an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, without reducing the R-peak detection performance compared to the existing R-peak detection schemes. Validation of the algorithm is performed on three manually annotated datasets. With a detection error rate of 0.23%, 1.32% and 9.42% on the MIT/BIH Arrhythmia and in-house maternal and fetal databases, respectively, the detection rate of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity.

  20. Detection rate of PET/CT in patients with biochemical relapse of prostate cancer using [{sup 68}Ga]PSMA I and T and comparison with published data of [{sup 68}Ga]PSMA HBED-CC

    Energy Technology Data Exchange (ETDEWEB)

    Berliner, Christoph; Tienken, Milena; Kobayashi, Yuske; Helberg, Annabelle; Kirchner, Uve; Klutmann, Susanne; Mester, Janos; Bannas, Peter [University Medical Center Hamburg-Eppendorf, Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg (Germany); Frenzel, Thorsten [University Medical Center Hamburg-Eppendorf, Ambulatory Center, Department for Radiation Oncology, Hamburg (Germany); Beyersdorff, Dirk [University Medical Center Hamburg-Eppendorf, Diagnostic and Interventional Radiology and Nuclear Medicine, Hamburg (Germany); University Medical Center Hamburg-Eppendorf, Martini-Klinik, Hamburg (Germany); Budaeus, Lars [University Medical Center Hamburg-Eppendorf, Martini-Klinik, Hamburg (Germany); Wester, Hans-Juergen [Technical University Munich, Pharmaceutical Radiochemistry, Garching (Germany)

    2017-04-15

    To determine the detection rate of PET/CT in biochemical relapse of prostate cancer using [{sup 68}Ga]PSMA I and T and to compare it with published detection rates of [{sup 68}Ga]PSMA HBED-CC. We performed a retrospective analysis in 83 consecutive patients with documented biochemical relapse after prostatectomy. All patients underwent whole body [{sup 68}Ga]PSMA I and T PET/CT. PET/CT images were evaluated for presence of local recurrence, lymph node metastases, and distant metastases. Proportions of positive PET/CT results were calculated for six subgroups with increasing prostate specific antigen (PSA) levels (<0.5 ng/mL, 0.5 to <1.0 ng/mL, 1.0 to <2.0 ng/mL, 2.0 to <5.0 ng/mL, 5.0 to <10.0, ≥10.0 ng/mL). Detection rates of [{sup 68}Ga]PSMA I and T were statistically compared with published detection rates of [{sup 68}Ga]PSMA HBED-CC using exact Fisher's test. Median PSA was 0.81 (range: 0.01 - 128) ng/mL. In 58/83 patients (70 %) at least one [{sup 68}Ga]PSMA I and T positive lesion was detected. Local recurrent cancer was present in 18 patients (22 %), lymph node metastases in 29 patients (35 %), and distant metastases in 15 patients (18 %). The tumor detection rate was positively correlated with PSA levels, resulting in detection rates of 52 % (<0.5 ng/mL), 55 % (0.5 to <1.0 ng/mL), 70 % (1.0 to <2.0 ng/mL), 93 % (2.0 to <5.0 ng/mL), 100 % (5.0 to <10.0 ng/mL), and 100 % (≥10.0 ng/mL). There was no significant difference between the detection rate of [{sup 68}Ga]PSMA I and T and published detection rates of [{sup 68}Ga]PSMA HBED-CC (all p>0.05). [{sup 68}Ga]PSMA I and T PET/CT has high detection rates of recurrent prostate cancer that are comparable to [{sup 68}Ga]PSMA HBED-CC. (orig.)

  1. Improved rate control for electron-beam evaporation and evaluation of optical performance improvements.

    Science.gov (United States)

    Gevelber, Michael; Xu, Bing; Smith, Douglas

    2006-03-01

    A new deposition-rate-control and electron-beam-gun (e-gun) strategy was developed that significantly reduces the growth-rate variations for e-beam-deposited SiO2 coatings. The resulting improvements in optical performance are evaluated for multilayer bandpass filters. The adverse effect of uneven silica-source depletion on coating spectral performances during long deposition runs is discussed.

  2. Evaluation of the clinical performance of the Abbott RealTime High-Risk HPV for carcinogenic HPV detection.

    Science.gov (United States)

    Halfon, Philippe; Benmoura, Dominique; Agostini, Aubert; Khiri, Hacene; Penaranda, Guillaume; Martineau, Agnes; Blanc, Bernard

    2010-08-01

    Abbott RealTime (RT) High-Risk (HR) HPV assay is a new qualitative real-time polymerase chain reaction (PCR) based assay for the detection of 14 HR HPV DNA. The assay can differentiate between the infection by HPV 16, HPV 18 and non-HPV 16/18 types through the distinct fluorescent labels on the type specific probes. To evaluate the clinical performance of the Abbott RT HR HPV test, in comparison with biopsy, Hybrid Capture II (HCII), and Linear Array (LA), for detection of high-grade disease (CIN2+). The study population consisted of 143 women who were included in three referral gynecology clinics in Marseilles (France) between March 2007 and June 2008. The clinical performance of the RT HR HPV assay, performed on the fully automated m2000 system, was compared with HCII and LA. HR HPV positivity rate was similar for all tests (Abbott RT HR HPV and HCII, 62%, and LA 63%). All tests had high sensitivities and negative predictive values for CIN2+ detection (>90%). The agreement between HCII and Abbott RT HR HPV, and between HCII and LA were 93% (k=0.85) and 96% (k=0.91) respectively. As expected, HPV16 or HPV18 positivity was greater in advanced grades of disease, especially in CIN2+ patients: 85% in CIN2+ vs. 33% in Abbott RT HR HPV assay is good and closely correlated with the two other assays. The automation and ability to identify type 16 and 18 make this a very attractive option for HPV testing in laboratories and potentially provides improved patient management. Copyright 2010. Published by Elsevier B.V.

  3. Effect of Radiologists’ Diagnostic Work-up Volume on Interpretive Performance

    Science.gov (United States)

    Anderson, Melissa L.; Smith, Robert A.; Carney, Patricia A.; Miglioretti, Diana L.; Monsees, Barbara S.; Sickles, Edward A.; Taplin, Stephen H.; Geller, Berta M.; Yankaskas, Bonnie C.; Onega, Tracy L.

    2014-01-01

    Purpose To examine radiologists’ screening performance in relation to the number of diagnostic work-ups performed after abnormal findings are discovered at screening mammography by the same radiologist or by different radiologists. Materials and Methods In an institutional review board–approved HIPAA-compliant study, the authors linked 651 671 screening mammograms interpreted from 2002 to 2006 by 96 radiologists in the Breast Cancer Surveillance Consortium to cancer registries (standard of reference) to evaluate the performance of screening mammography (sensitivity, false-positive rate [FPRfalse-positive rate], and cancer detection rate [CDRcancer detection rate]). Logistic regression was used to assess the association between the volume of recalled screening mammograms (“own” mammograms, where the radiologist who interpreted the diagnostic image was the same radiologist who had interpreted the screening image, and “any” mammograms, where the radiologist who interpreted the diagnostic image may or may not have been the radiologist who interpreted the screening image) and screening performance and whether the association between total annual volume and performance differed according to the volume of diagnostic work-up. Results Annually, 38% of radiologists performed the diagnostic work-up for 25 or fewer of their own recalled screening mammograms, 24% performed the work-up for 0–50, and 39% performed the work-up for more than 50. For the work-up of recalled screening mammograms from any radiologist, 24% of radiologists performed the work-up for 0–50 mammograms, 32% performed the work-up for 51–125, and 44% performed the work-up for more than 125. With increasing numbers of radiologist work-ups for their own recalled mammograms, the sensitivity (P = .039), FPRfalse-positive rate (P = .004), and CDRcancer detection rate (P work-ups for any radiologist yielded significant increases in FPRfalse-positive rate (P = .011) and CDRcancer detection rate (P

  4. Incremental Diagnostic Performance of Combined Parameters in the Detection of Severe Coronary Artery Disease Using Exercise Gated Myocardial Perfusion Imaging.

    Directory of Open Access Journals (Sweden)

    Chia-Ju Liu

    Full Text Available Myocardial perfusion imaging (MPI using gated single-photon emission tomography (gSPECT may underestimate the severity of coronary artery disease (CAD. This study aimed to evaluate the significance of combined parameters derived from gSPECT, as well as treadmill stress test parameters, in the detection of severe CAD.A total of 211 consecutive patients referred for exercise MPI between June 2011 and June 2013 (who received invasive coronary angiography within six months after MPI were retrospectively reviewed. Exercise MPI was performed with Bruce protocol and 201Tl injected at peak exercise. Gated SPECT was performed using a cadmium-zinc-telluride camera and processed by QPS/QGS software. Perfusion defect abnormalities such as sum stress score (SSS; sum difference score, algorithm-derived total perfusion deficits, transient ischemic dilatation ratios of end-diastolic volumes and end-systolic volumes, post-stress changes in ejection fraction, and lung/heart ratio (LHR were calculated. Treadmill parameters, including ST depression (STD at the 1st and 3rd minutes of recovery stage (1'STD and 3'STD, maximal STD corrected by heart rate increment (ST/HR, heart rate decline in 1st and 3rd minutes of recovery stage, recovery heart rate ratio (HR ratio, systolic and mean blood pressure ratios (SBP ratio and MAP ratio during recovery phase were recorded. Diagnostic performances of these parameters were analyzed with receiver operating characteristic (ROC analysis and logistic regression for detection of left main (≥ 50% or 3-vessel disease (all ≥ 70% luminal stenosis on invasive angiography.Among various MPI and treadmill parameters used for detection of severe CAD, SSS and ST/HR had the highest AUC (0.78, 0.73, p = NS and best cut-off values (SSS > 6, ST/HR > 17.39 10-2mV/bpm, respectively. By univariate logistic regression, all parameters except 1'HRR, 3'HRR, SBP and MAP ratios increased the odds ratio of severe CAD. Only increased L/H ratio, 3'STD

  5. Performance of an RPM based on Gd-lined plastic scintillator for neutron and gamma detection [ANIMMA--2015-IO-372

    Energy Technology Data Exchange (ETDEWEB)

    Fanchini, Erica [INFN/ANN and SCINTILLA groups, Isituto Nazionale di Fisica Nucleare - INFN (Italy)

    2015-07-01

    A Radiation Portal Monitor (RPM) was developed by the Istituto Nazionale di Fisica Nucleare (INFN) and Ansaldo Nucleare (ANN) within the FP7 SCINTILLA European project. The system was designed to detect both gamma and neutron radiation with a single technology. It is conceived to monitor vehicle and cargo containers in transits across borders or ports, to find radioactive elements and to avoid illegal trafficking of strategic nuclear materials. The system is based on a {sup 3}He-free neutron detection technology using plastic scintillators coupled to Gadolinium to detect and discriminate gamma from neutron signals. During the 3 years of the SCINTILLA project the construction and test of the first two prototypes drove the definition of the final layout of a full RPM system consisting of two twin pillars as a portal for vehicle and cargo container scan. A custom System Control Software (SCS) manages the electronics of the RPM, the ancillary devices and the data analysis. The combination of the detector layout and of the software functionalities enables both to distinguish neutrons and gammas and to identify the energy range of a detected gamma source. The system was initially characterized via static tests with gamma and neutron sources in the INFN laboratory. These measurements were used to calibrate the detector, evaluate the response of the single pillars as well as of the full system, and optimize the RPM configuration and discrimination algorithm. During this phase, specific tests were performed to study the stability over time of the system, monitoring the measured the neutron and gamma count rates over periods of several weeks. The results allow us to demonstrate the reliability and robustness of the RPM. In a second time the RPM performance was studied via dynamic tests performed during the SCINTILLA test and benchmark campaigns. These measurements took place in the JRC ITRAP+10 facility at Ispra (Varese-Italy). The laboratory is equipped with an experimental

  6. A method of detection of respiration rate on Android using UWB Impulse Radar

    Directory of Open Access Journals (Sweden)

    Young-Jin Park

    2016-12-01

    Full Text Available Monitoring respiration rate is important because it can help to detect and prevent abnormal respiratory rates that can lead to cardiac arrest and chronic obstructive pulmonary disease. Nowadays, most medical measurement and monitoring devices are either invasive or wired but people are hesitant to attach physiological sensors to their body. In this study, we investigated whether real-time medical measurement of breathing using Novelda’s Ultra-Wideband Impulse Radio (IR-UWB–which does not need to be attached to the human body and is also non-invasive–is possible on Android. Experimental results obtained were found to be comparable to those of a commercial healthcare device.

  7. Data-Driven Anomaly Detection Performance for the Ares I-X Ground Diagnostic Prototype

    Science.gov (United States)

    Martin, Rodney A.; Schwabacher, Mark A.; Matthews, Bryan L.

    2010-01-01

    In this paper, we will assess the performance of a data-driven anomaly detection algorithm, the Inductive Monitoring System (IMS), which can be used to detect simulated Thrust Vector Control (TVC) system failures. However, the ability of IMS to detect these failures in a true operational setting may be related to the realistic nature of how they are simulated. As such, we will investigate both a low fidelity and high fidelity approach to simulating such failures, with the latter based upon the underlying physics. Furthermore, the ability of IMS to detect anomalies that were previously unknown and not previously simulated will be studied in earnest, as well as apparent deficiencies or misapplications that result from using the data-driven paradigm. Our conclusions indicate that robust detection performance of simulated failures using IMS is not appreciably affected by the use of a high fidelity simulation. However, we have found that the inclusion of a data-driven algorithm such as IMS into a suite of deployable health management technologies does add significant value.

  8. State Performance-Based Regulation Using Multiyear Rate Plans for U.S. Electric Utilities

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Mark Newton [Pacific Economics Group Research LLC (United States); Makos, Matt [Pacific Economics Group Research LLC (United States); Deason, Jeff [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-07-31

    Electric utilities today must contain costs at a time when many need to modernize aging systems and all face major changes in technologies, customer preferences and competitive pressures.Most U.S. electric utility facilities are investor-owned, subject to rate and service regulation by state public utility commissions. Regulatory systems under which these utilities operate affect their performance and ability to meet these challenges. In this business environment, multiyear rate plans have some advantages over traditional rate regulation.The report focuses on key design issues and provides case studies of the multiyear rate plan approach, applicable to both vertically integrated and restructured states. Mark Newton Lowry and Matt Makos of Pacific Energy Group Research and Jeff Deason of Berkeley Lab authored the report; Lisa Schwartz, Berkeley Lab, was project manager and technical editor.The report is aimed primarily at state utility regulators and stakeholders in the state regulatory process. The multiyear rate approach also provides ideas on how to streamline oversight of public power utilities and rural electric cooperatives for their governing boards.Two key provisions of multiyear rate plans strengthen cost containment incentives and streamline regulation: 1. Reducing frequency of rate cases, typically to every four or five years 2. Using an attrition relief mechanism to escalate rates or revenue between rate cases to address cost pressures such as inflation and growth in number of customers, independently of the utility’s own cost Better utility performance can be achieved under well-designed multiyear rate plans while achieving lower regulatory costs. Benefits can be shared between utilities and their customers. But plans can be complex and involve significant changes in the regulatory system. Designing plans that stimulate utility performance without undue risk and share benefits fairly can be challenging.This report discusses the rationale for multiyear

  9. LASER: A Maximum Likelihood Toolkit for Detecting Temporal Shifts in Diversification Rates From Molecular Phylogenies

    Directory of Open Access Journals (Sweden)

    Daniel L. Rabosky

    2006-01-01

    Full Text Available Rates of species origination and extinction can vary over time during evolutionary radiations, and it is possible to reconstruct the history of diversification using molecular phylogenies of extant taxa only. Maximum likelihood methods provide a useful framework for inferring temporal variation in diversification rates. LASER is a package for the R programming environment that implements maximum likelihood methods based on the birth-death process to test whether diversification rates have changed over time. LASER contrasts the likelihood of phylogenetic data under models where diversification rates have changed over time to alternative models where rates have remained constant over time. Major strengths of the package include the ability to detect temporal increases in diversification rates and the inference of diversification parameters under multiple rate-variable models of diversification. The program and associated documentation are freely available from the R package archive at http://cran.r-project.org.

  10. Sleep Apnoea Detection in Single Channel ECGs by Analyzing Heart Rate Dynamics

    National Research Council Canada - National Science Library

    Zywietz, C

    2001-01-01

    .... Our analysis is based on spectral components of heart rate variability. Frequency analysis was performed using Fourier and wavelet transformation with appropriate application of the Hilbert transform...

  11. An Integrated Intrusion Detection Model of Cluster-Based Wireless Sensor Network.

    Science.gov (United States)

    Sun, Xuemei; Yan, Bo; Zhang, Xinzhong; Rong, Chuitian

    2015-01-01

    Considering wireless sensor network characteristics, this paper combines anomaly and mis-use detection and proposes an integrated detection model of cluster-based wireless sensor network, aiming at enhancing detection rate and reducing false rate. Adaboost algorithm with hierarchical structures is used for anomaly detection of sensor nodes, cluster-head nodes and Sink nodes. Cultural-Algorithm and Artificial-Fish-Swarm-Algorithm optimized Back Propagation is applied to mis-use detection of Sink node. Plenty of simulation demonstrates that this integrated model has a strong performance of intrusion detection.

  12. Using Dictionary Pair Learning for Seizure Detection.

    Science.gov (United States)

    Ma, Xin; Yu, Nana; Zhou, Weidong

    2018-02-13

    Automatic seizure detection is extremely important in the monitoring and diagnosis of epilepsy. The paper presents a novel method based on dictionary pair learning (DPL) for seizure detection in the long-term intracranial electroencephalogram (EEG) recordings. First, for the EEG data, wavelet filtering and differential filtering are applied, and the kernel function is performed to make the signal linearly separable. In DPL, the synthesis dictionary and analysis dictionary are learned jointly from original training samples with alternating minimization method, and sparse coefficients are obtained by using of linear projection instead of costly [Formula: see text]-norm or [Formula: see text]-norm optimization. At last, the reconstructed residuals associated with seizure and nonseizure sub-dictionary pairs are calculated as the decision values, and the postprocessing is performed for improving the recognition rate and reducing the false detection rate of the system. A total of 530[Formula: see text]h from 20 patients with 81 seizures were used to evaluate the system. Our proposed method has achieved an average segment-based sensitivity of 93.39%, specificity of 98.51%, and event-based sensitivity of 96.36% with false detection rate of 0.236/h.

  13. Consensus review of discordant findings maximizes cancer detection rate in double-reader screening mammography: Irish National Breast Screening Program experience.

    Science.gov (United States)

    Shaw, Colette M; Flanagan, Fidema L; Fenlon, Helen M; McNicholas, Michelle M

    2009-02-01

    To assesses consensus review of discordant screening mammography findings in terms of its sensitivity, safety, and effect on overall performance in the first 6 years of operation of the Irish National Breast Screening Program (NBSP). Women who participated in the Irish NBSP gave written informed consent for use of their data for auditing purposes. Local ethics committee approval was obtained. The study population consisted of women who participated in the Irish NBSP and underwent initial screening mammography at one of the two screening centers serving the eastern part of Ireland between 2000 and 2005. Independent double reading of mammograms was performed. When the readers disagreed regarding referral, the case was reviewed by a consensus panel. Of the 128 569 screenings performed, 1335 (1%) were discussed by consensus. Of the 1335 cases discussed by consensus, 606 (45.39%) were recalled for further assessment. This resulted in an overall recall rate of 4.41%. In those recalled to assessment, 71 cases of malignant disease were diagnosed (ductal carcinoma in situ, n = 24; invasive cancer, n = 47). The remaining 729 patients were returned to biennial screening. Of these 729 patients, seven had false-negative findings that were identified in the subsequent screening round. Use of the highest reader recall method, in which a patient is recalled if her findings are deemed abnormal by either reader, could potentially increase the cancer detection rate by 0.6 per 1000 women screened but would increase the recall rate by 12.69% and the number of false-positive findings by 15.37%. The consensus panel identified 71 (7.33%) of 968 cancers diagnosed. Consensus review substantially reduced the number of cases recalled and was associated with a low false-negative rate.

  14. Effect of Heart Rate Variability Biofeedback on Sport Performance, a Systematic Review.

    Science.gov (United States)

    Jiménez Morgan, Sergio; Molina Mora, José Arturo

    2017-09-01

    Aim is to determine if the training with heart rate variability biofeedback allows to improve performance in athletes of different disciplines. Methods such as database search on Web of Science, SpringerLink, EBSCO Academic Search Complete, SPORTDiscus, Pubmed/Medline, and PROQUEST Academic Research Library, as well as manual reference registration. The eligibility criteria were: (a) published scientific articles; (b) experimental studies, quasi-experimental, or case reports; (c) use of HRV BFB as main treatment; (d) sport performance as dependent variable; (e) studies published until October 2016; (f) studies published in English, Spanish, French or Portuguese. The guidelines of the PRISMA statement were followed. Out of the 451 records found, seven items were included. All studies had a small sample size (range from 1 to 30 participants). In 85.71% of the studies (n = 6) the athletes enhanced psychophysiological variables that allowed them to improve their sport performance thanks to training with heart rate variability biofeedback. Despite the limited amount of experimental studies in the field to date, the findings suggest that heart rate variability biofeedback is an effective, safe, and easy-to-learn and apply method for both athletes and coaches in order to improve sport performance.

  15. Noise-tolerant instantaneous heart rate and R-peak detection using short-term autocorrelation for wearable healthcare systems.

    Science.gov (United States)

    Fujii, Takahide; Nakano, Masanao; Yamashita, Ken; Konishi, Toshihiro; Izumi, Shintaro; Kawaguchi, Hiroshi; Yoshimoto, Masahiko

    2013-01-01

    This paper describes a robust method of Instantaneous Heart Rate (IHR) and R-peak detection from noisy electrocardiogram (ECG) signals. Generally, the IHR is calculated from the R-wave interval. Then, the R-waves are extracted from the ECG using a threshold. However, in wearable bio-signal monitoring systems, noise increases the incidence of misdetection and false detection of R-peaks. To prevent incorrect detection, we introduce a short-term autocorrelation (STAC) technique and a small-window autocorrelation (SWAC) technique, which leverages the similarity of QRS complex waveforms. Simulation results show that the proposed method improves the noise tolerance of R-peak detection.

  16. Kepler Planet Detection Metrics: Per-Target Detection Contours for Data Release 25

    Science.gov (United States)

    Burke, Christopher J.; Catanzarite, Joseph

    2017-01-01

    A necessary input to planet occurrence calculations is an accurate model for the pipeline completeness (Burke et al., 2015). This document describes the use of the Kepler planet occurrence rate products in order to calculate a per-target detection contour for the measured Data Release 25 (DR25) pipeline performance. A per-target detection contour measures for a given combination of orbital period, Porb, and planet radius, Rp, what fraction of transit signals are recoverable by the Kepler pipeline (Twicken et al., 2016; Jenkins et al., 2017). The steps for calculating a detection contour follow the procedure outlined in Burke et al. (2015), but have been updated to provide improved accuracy enabled by the substantially larger database of transit injection and recovery tests that were performed on the final version (i.e., SOC 9.3) of the Kepler pipeline (Christiansen, 2017; Burke Catanzarite, 2017a). In the following sections, we describe the main inputs to the per-target detection contour and provide a worked example of the python software released with this document (Kepler Planet Occurrence Rate Tools KeplerPORTs)1 that illustrates the generation of a detection contour in practice. As background material for this document and its nomenclature, we recommend the reader be familiar with the previous method of calculating a detection contour (Section 2 of Burke et al.,2015), input parameters relevant for describing the data quantity and quality of Kepler targets (Burke Catanzarite, 2017b), and the extensive new transit injection and recovery tests of the Kepler pipeline (Christiansen et al., 2016; Burke Catanzarite, 2017a; Christiansen, 2017).

  17. Assay for dihydroorotase using high-performance liquid chromatography with radioactivity detection

    International Nuclear Information System (INIS)

    Mehdi, S.; Wiseman, J.S.

    1989-01-01

    An assay for measuring dihydroorotase activity was devised. Radiolabeled substrate and product were separated by high-performance liquid chromatography using a reverse-phase column with ion-pairing, and the radioactivity was quantitated by flow detection

  18. Blurred digital mammography images: an analysis of technical recall and observer detection performance.

    Science.gov (United States)

    Ma, Wang Kei; Borgen, Rita; Kelly, Judith; Millington, Sara; Hilton, Beverley; Aspin, Rob; Lança, Carla; Hogg, Peter

    2017-03-01

    Blurred images in full-field digital mammography are a problem in the UK Breast Screening Programme. Technical recalls may be due to blurring not being seen on lower resolution monitors used for review. This study assesses the visual detection of blurring on a 2.3-MP monitor and a 5-MP report grade monitor and proposes an observer standard for the visual detection of blurring on a 5-MP reporting grade monitor. 28 observers assessed 120 images for blurring; 20 images had no blurring present, whereas 100 images had blurring imposed through mathematical simulation at 0.2, 0.4, 0.6, 0.8 and 1.0 mm levels of motion. Technical recall rate for both monitors and angular size at each level of motion were calculated. χ 2 tests were used to test whether significant differences in blurring detection existed between 2.3- and 5-MP monitors. The technical recall rate for 2.3- and 5-MP monitors are 20.3% and 9.1%, respectively. The angular size for 0.2- to 1-mm motion varied from 55 to 275 arc s. The minimum amount of motion for visual detection of blurring in this study is 0.4 mm. For 0.2-mm simulated motion, there was no significant difference [χ 2 (1, N = 1095) = 1.61, p = 0.20] in blurring detection between the 2.3- and 5-MP monitors. According to this study, monitors ≤2.3 MP are not suitable for technical review of full-field digital mammography images for the detection of blur. Advances in knowledge: This research proposes the first observer standard for the visual detection of blurring.

  19. Performance Evaluation of Target Detection with a Near-Space Vehicle-Borne Radar in Blackout Condition.

    Science.gov (United States)

    Li, Yanpeng; Li, Xiang; Wang, Hongqiang; Deng, Bin; Qin, Yuliang

    2016-01-06

    Radar is a very important sensor in surveillance applications. Near-space vehicle-borne radar (NSVBR) is a novel installation of a radar system, which offers many benefits, like being highly suited to the remote sensing of extremely large areas, having a rapidly deployable capability and having low vulnerability to electronic countermeasures. Unfortunately, a target detection challenge arises because of complicated scenarios, such as nuclear blackout, rain attenuation, etc. In these cases, extra care is needed to evaluate the detection performance in blackout situations, since this a classical problem along with the application of an NSVBR. However, the existing evaluation measures are the probability of detection and the receiver operating curve (ROC), which cannot offer detailed information in such a complicated application. This work focuses on such requirements. We first investigate the effect of blackout on an electromagnetic wave. Performance evaluation indexes are then built: three evaluation indexes on the detection capability and two evaluation indexes on the robustness of the detection process. Simulation results show that the proposed measure will offer information on the detailed performance of detection. These measures are therefore very useful in detecting the target of interest in a remote sensing system and are helpful for both the NSVBR designers and users.

  20. Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H. [Dept. of Intelligent Image Information, Graduate Scholl of Medicine, Gifu Univ. (Japan); Asano, T.; Kato, H.; Hoshi, H. [Dept. of Radiology, Graduate Scholl of Medicine, Gifu Univ. (Japan); Yamakawa, H.; Iwama, T. [Dept. of Neurosurgery, Graduate Scholl of Medicine, Gifu Univ. (Japan); Ando, H. [Dept. of Neurosurgery, Gifu Municipal Hospital (Japan); Yamakawa, H. [Dept. of Emergency and Critical Care Medicine, Chuno-Kousei Hospital (Japan)

    2007-06-15

    The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

  1. ORIGINAL ARTICLE: Will An Additional Observer Enhance Adenoma Detection During Colonoscopy?

    Directory of Open Access Journals (Sweden)

    Kevin D Mullen

    2012-07-01

    Full Text Available Background: Due to varied level of experience, the detection rate of adenoma on colonoscopy is different. In presence of both fellows and attending the incidence rates of adenoma are shown to increase in a small study reported by Rogart et al [4]. Based on similar hypothesis, a study was undertaken with much larger sample size to improve the power of the study. Aims and objective: To know if presence of additional observer will enhance adenoma detection during colonoscopy. Material and Methods: 2236 consecutive colonoscopies performed at Metro Health Medical Centre, Cleveland, Ohio were included in the study from July 2005 to August 2006. Cases with history of colorectal, surgical resection of colon, inflammatory bowel diseases and hereditary polyposis syndrome were excluded. Inpatient colonoscopies were also excluded. With all usual precautions for colonoscopy and after giving polyethylene glycol electrolyte (PEGEL colonoscopies were performed by one of the nine experienced staff attending using an Olympus colonoscope and Evis Exera processors. All colonoscopies performed by fellows were supervised by an attending throughout the procedure. Advanced adenomas were defined as adenomas greater than 1 cm size. Statistical analysis was done using Tall hassee, FL software; Fisher’s exact test, unpaired t test and multiple logistic regression analysis were performed. p-value of <0.05 is considered as statistically significant. Results: Of the total 2236 colonoscopies included in the study, 1527 were performed by fellows under supervision of attending and 709 by the attending. There was no significant difference in patient demographics, caecal intubation or poor preparation colonoscopies. The mean age of the group was 55 years in both of the groups. There was no statistically significant different in the polyp detection rate (35% Vs 36.8% as well as overall adenoma detection rate (28.4% Vs 27.7% between these two groups of performers. However

  2. Binary and multi-category ratings in a laboratory observer performance study: A comparison

    OpenAIRE

    Gur, David; Bandos, Andriy I.; King, Jill L.; Klym, Amy H.; Cohen, Cathy S.; Hakim, Christiane M.; Hardesty, Lara A.; Ganott, Marie A.; Perrin, Ronald L.; Poller, William R.; Shah, Ratan; Sumkin, Jules H.; Wallace, Luisa P.; Rockette, Howard E.

    2008-01-01

    The authors investigated radiologists, performances during retrospective interpretation of screening mammograms when using a binary decision whether to recall a woman for additional procedures or not and compared it with their receiver operating characteristic (ROC) type performance curves using a semi-continuous rating scale. Under an Institutional Review Board approved protocol nine experienced radiologists independently rated an enriched set of 155 examinations that they had not personally...

  3. Performances evaluation of the coincidence detection on a gamma-camera

    International Nuclear Information System (INIS)

    Dreuille, O. de; Gaillard, J.F.; Brasse, D.; Bendriem, B.; Groiselle, C.; Rocchisani, J.M.; Moretti, J.L.

    2000-01-01

    The performance of the VERTEX gamma-camera (ADAC) working in coincidence mode are investigated using a protocol derived from the NEMA and IEC recommendations. With a field of view determined by two rectangular detectors (50.8 cm x 40 cm) composed of NaI crystal, this camera allows a 3-D acquisition with different energy window configurations: photopeak-photopeak only (PP) and photopeak-photopeak + photopeak-Compton (PC). An energy resolution of 11% and a scatter fraction of 27% and 33% for the 3D-PP and 3D-PC mode respectively are the main significant results of our study. The spatial resolution equals 5.9 mm and the limit of the detectability ranges from 16 mm to 13 mm for a contrast of 2.5: as a function of the random estimation, the maximum of the Noise Equivalent Count rate varies from 3 kcps to 4.5 kcps for the PP mode and from 3.85 kcps to 6.1 kcps for the PC mode. These maxima are reached for a concentration of 8 kBq/ml for the PP mode and 5 kBq/ml for the PC mode. These values are compared with the results obtained by other groups for the VERTEX gamma camera and several dedicated PET systems. (authors)

  4. Adaptive rate selection scheme for video transmission to resolve IEEE 802.11 performance anomaly

    Science.gov (United States)

    Tang, Guijin; Zhu, Xiuchang

    2011-10-01

    Multi-rate transmission may lead to performance anomaly in an IEEE 802.11 network. It will decrease the throughputs of all the higher rate stations. This paper proposes an adaptive rate selection scheme for video service when performance anomaly occurs. Considering that video has the characteristic of tolerance to packet loss, we actively drop several packets so as to select the rates as high as possible for transmitting packets. Experiment shows our algorithm can decrease the delay and jitter of video, and improve the system throughput as well.

  5. [Detection of monoamine neurotransmitters and its metabolites by high performance liquid chromatograph after pre-column derivatization of dansyl chloride column].

    Science.gov (United States)

    Huang, Xiao; Chen, Jia-wen; He, Li-ping; Kang, Xue-jun

    2012-12-01

    To develop a high performance liquid chromatography (HPLC) for detection of monoamine neurotransmitters and its metabolites after pre-column derivatization with dansyl chloride. The C(18) chromatograph column (150 mm×4.6 mm×5 µm) was selected for detection, and derived by dansyl chloride (10 mg/ml) under the condition of 50°C water bath by pH11 buffer solution. 20 µl acetic acid acetone solution (1.0 mol/L) was then mixed in for termination of the reaction. Then the solution was cooling to room temperature, 0.1 mol/L acetic acid zinc-acetonitrile-tetrahydrofuran solution was adopted for mobile phrase, with the volume ratio at 62:35:3. The flow rate was 1.0 ml/min between 0-10 min, 2.0 ml/min between 10-35 min. The ultraviolet detection wavelength was 286 nm. The above method separately detected monoamine neurotransmitters and its metabolites and evaluated the limit of detection, accurate degree and accuracy degree. The linear relations between each component was good in the range of 1 - 20 µg/ml (r = 0.999). The lowest detection limit of norepinephrine, dopamine, 5-hydroxytryptamine and the metabolites 3-methoxy-4-benzoglycols, homovanillic acid and 5-heteroauxin were separately 0.60, 0.80, 0.41, 0.21, 0.19 and 0.1 µg/ml; while the average recovery rates were between 78.5% - 95.9%, and the relative standard deviation (RSD) was 6.62%, 7.64%, 2.98%, 3.60%, 5.09% and 3.09%, respectively. In the process of selection and optimization of the chromatographic conditions, we observed the importance of metal ions to discretion, and discussed the temperature, pH of the buffer solution and dosage of dansyl chloride in derivation. Under the above conditions, the reaction was perfect, and the baseline of the detected materials thoroughly separated. The method to detect monoamine neurotransmitters and its metabolites by HPLC and pre-column derivatization with dansyl chloride was established; and this method could provide reference for the detection of polyamine by HPLC.

  6. The combined bowling rate as a measure of bowling performance in ...

    African Journals Online (AJOL)

    A single measure that can be used to assess the performance of bowlers in cricket is defined. This study shows how it can be used to rank bowlers. The performance of bowlers is generally measured by using three different criteria, i.e. the average number of runs conceded per wicket taken (A), the economy rate (E), which ...

  7. Review of recycling performance indicators: a study on collection rate in Taiwan.

    Science.gov (United States)

    Wen, Lihchyi; Lin, Chun-Hsu; Lee, Soo-Cheol

    2009-08-01

    The Taiwan Environmental Protection Administration (Taiwan EPA) launched a national Extended Producer Responsibility (EPR) system after integrating eight private recycling organizations in 1998. After that, the environmental performance of the EPR system brought a lot of attention to policy makers. Many studies show positive environmental effects of the EPR system in Taiwan. However, there are controversial questions remained, such as whether the performance indicators used are the right choice to estimate the environmental effects of the recycling policy? Can those estimated results really reflect the performance of the system? This paper would therefore like to more accurately evaluate the performance indicators of the EPR system based on data observed over the past decade in Taiwan. In the process of evaluating the performance indicators, we have found that the collection rates for durable goods are often ignored in countries that pursue a zero waste policy. This may affect the actual recycling outcome and resource direction targeted by producers. However, in order for the collection rate to be adopted as a policy indicator, how to estimate the amounts of retired or waste products during a period is critical. In this paper, we estimate the collection rate for electrical and electronic waste by using the survival analysis and ownership data analysis approaches. We also provide a comparison of both approaches and put forward suggestions for directions in the future in solid waste management.

  8. Review of recycling performance indicators: A study on collection rate in Taiwan

    International Nuclear Information System (INIS)

    Wen Lihchyi; Lin Chunhsu; Lee, Soo-cheol

    2009-01-01

    The Taiwan Environmental Protection Administration (Taiwan EPA) launched a national Extended Producer Responsibility (EPR) system after integrating eight private recycling organizations in 1998. After that, the environmental performance of the EPR system brought a lot of attention to policy makers. Many studies show positive environmental effects of the EPR system in Taiwan. However, there are controversial questions remained, such as whether the performance indicators used are the right choice to estimate the environmental effects of the recycling policy? Can those estimated results really reflect the performance of the system? This paper would therefore like to more accurately evaluate the performance indicators of the EPR system based on data observed over the past decade in Taiwan. In the process of evaluating the performance indicators, we have found that the collection rates for durable goods are often ignored in countries that pursue a zero waste policy. This may affect the actual recycling outcome and resource direction targeted by producers. However, in order for the collection rate to be adopted as a policy indicator, how to estimate the amounts of retired or waste products during a period is critical. In this paper, we estimate the collection rate for electrical and electronic waste by using the survival analysis and ownership data analysis approaches. We also provide a comparison of both approaches and put forward suggestions for directions in the future in solid waste management.

  9. Diagnostic performance of dual-source CT coronary angiography with and without heart rate control: Systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Li, M.; Zhang, G.-M.; Zhao, J.-S.; Jiang, Z.-W.; Peng, Z.-H.; Jin, Z.-T.; Sun, G.

    2014-01-01

    Aim: To investigate the diagnostic accuracy of dual-source computed tomography (DSCT) coronary angiography with and without the application of a β-blocker. Materials and methods: An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize diagnostic test data. Results: The pooled sensitivity at the patient level was 0.98 [95% confidence intervals (CI): 0.97–0.99], and specificity 0.88 (95% CI: 0.84–0.91). The results showed that without heart rate control, the sensitivity and specificity at the patient level did not decrease (p = 0.27 and 0.56, respectively). At the artery level, no significant differences in sensitivity and specificity for studies with and without heart rate control were detected (p = 0.04 and 0.05, respectively). At the segment level, the specificity decreased without heart rate control (p = 0.03), whereas the sensitivity was not influenced (p = 0.63). The median radiation exposure was 2.6 mSv, with 1.6 mSv and 8 mSv for heart rate-controlled studies and uncontrolled studies, respectively. Conclusions: DSCT coronary angiography without heart rate control has a similar excellent diagnostic performance at the patient level as that of heart rate control groups. However, controlling for heart rate to decrease radiation and to provide effective information for selecting the therapeutic strategy and risk stratification is recommended

  10. Improved detection rate of structural abnormalities in the first trimester using an extended examination protocol.

    Science.gov (United States)

    Iliescu, D; Tudorache, S; Comanescu, A; Antsaklis, P; Cotarcea, S; Novac, L; Cernea, N; Antsaklis, A

    2013-09-01

    To assess the potential of first-trimester sonography in the detection of fetal abnormalities using an extended protocol that is achievable with reasonable resources of time, personnel and ultrasound equipment. This was a prospective two-center 2-year study of 5472 consecutive unselected pregnant women examined at 12 to 13 + 6 gestational weeks. Women were examined using an extended morphogenetic ultrasound protocol that, in addition to the basic evaluation, involved a color Doppler cardiac sweep and identification of early contingent markers for major abnormalities. The prevalence of lethal and severe malformations was 1.39%. The first-trimester scan identified 40.6% of the cases detected overall and 76.3% of major structural defects. The first-trimester detection rate (DR) for major congenital heart disease (either isolated or associated with extracardiac abnormalities) was 90% and that for major central nervous system anomalies was 69.5%. In fetuses with increased nuchal translucency (NT), the first-trimester DR for major anomalies was 96%, and in fetuses with normal NT it was 66.7%. Most (67.1%) cases with major abnormalities presented with normal NT. A detailed first-trimester anomaly scan using an extended protocol is an efficient screening method to detect major fetal structural abnormalities in low-risk pregnancies. It is feasible at 12 to 13 + 6 weeks with ultrasound equipment and personnel already used for routine first-trimester screening. Rate of detection of severe malformations is greater in early- than in mid-pregnancy and on postnatal evaluation. Early heart investigation could be improved by an extended protocol involving use of color Doppler. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.

  11. High rate response of ultra-high-performance fiber-reinforced concretes under direct tension

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Ngoc Thanh [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Tran, Tuan Kiet [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Department of Civil Engineering and Applied Mechanics, Ho Chi Minh City University of Technology and Education, 01 Vo Van Ngan, Thu Duc District, Ho Chi Minh City (Viet Nam); Kim, Dong Joo, E-mail: djkim75@sejong.ac.kr [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of)

    2015-03-15

    The tensile response of ultra-high-performance fiber-reinforced concretes (UHPFRCs) at high strain rates (5–24 s{sup −} {sup 1}) was investigated. Three types of steel fibers, including twisted, long and short smooth steel fibers, were added by 1.5% volume content in an ultra high performance concrete (UHPC) with a compressive strength of 180 MPa. Two different cross sections, 25 × 25 and 25 × 50 mm{sup 2}, of tensile specimens were used to investigate the effect of the cross section area on the measured tensile response of UHPFRCs. Although all the three fibers generated strain hardening behavior even at high strain rates, long smooth fibers produced the highest tensile resistance at high rates whereas twisted fiber did at static rate. The breakages of twisted fibers were observed from the specimens tested at high strain rates unlike smooth steel fibers. The tensile behavior of UHPFRCs at high strain rates was clearly influenced by the specimen size, especially in post-cracking strength.

  12. A Pilot Evaluation of On-Road Detection Performance by Drivers with Hemianopia Using Oblique Peripheral Prisms

    Directory of Open Access Journals (Sweden)

    Alex R. Bowers

    2012-01-01

    Full Text Available Aims. Homonymous hemianopia (HH, a severe visual consequence of stroke, causes difficulties in detecting obstacles on the nonseeing (blind side. We conducted a pilot study to evaluate the effects of oblique peripheral prisms, a novel development in optical treatments for HH, on detection of unexpected hazards when driving. Methods. Twelve people with complete HH (median 49 years, range 29–68 completed road tests with sham oblique prism glasses (SP and real oblique prism glasses (RP. A masked evaluator rated driving performance along the 25 km routes on busy streets in Ghent, Belgium. Results. The proportion of satisfactory responses to unexpected hazards on the blind side was higher in the RP than the SP drive (80% versus 30%; P=0.001, but similar for unexpected hazards on the seeing side. Conclusions. These pilot data suggest that oblique peripheral prisms may improve responses of people with HH to blindside hazards when driving and provide the basis for a future, larger-sample clinical trial. Testing responses to unexpected hazards in areas of heavy vehicle and pedestrian traffic appears promising as a real-world outcome measure for future evaluations of HH rehabilitation interventions aimed at improving detection when driving.

  13. Performance of Four Transport and Storage Systems for Molecular Detection of Multidrug-Resistant Tuberculosis

    Science.gov (United States)

    Rabodoarivelo, Marie Sylvianne; Imperiale, Bélen; andrianiavomikotroka, Rina; Brandao, Angela; Kumar, Parveen; Singh, Sarman; Ferrazoli, Lucilaine; Morcillo, Nora; Rasolofo, Voahangy; Palomino, Juan Carlos; Vandamme, Peter; Martin, Anandi

    2015-01-01

    Background Detection of drug-resistant tuberculosis is essential for the control of the disease but it is often hampered by the limitation of transport and storage of samples from remote locations to the reference laboratory. We performed a retrospective field study to evaluate the performance of four supports enabling the transport and storage of samples to be used for molecular detection of drug resistance using the GenoType MTBDRplus. Methods Two hundred Mycobacterium tuberculosis strains were selected and spotted on slides, FTA cards, GenoCards, and in ethanol. GenoType MTBDRplus was subsequently performed with the DNA extracted from these supports. Sensitivity and specificity were calculated and compared to the results obtained by drug susceptibility testing. Results For all supports, the overall sensitivity and specificity for detection of resistance to RIF was between 95% and 100%, and for INH between 95% and 98%. Conclusion The four transport and storage supports showed a good sensitivity and specificity for the detection of resistance to RIF and INH in M. tuberculosis strains using the GenoType MTBDRplus. These supports can be maintained at room temperature and could represent an important alternative cost-effective method useful for rapid molecular detection of drug-resistant TB in low-resource settings. PMID:26431352

  14. Sensitivity of new detection method for ultra-low frequency gravitational waves with pulsar spin-down rate statistics

    Science.gov (United States)

    Yonemaru, Naoyuki; Kumamoto, Hiroki; Takahashi, Keitaro; Kuroyanagi, Sachiko

    2018-04-01

    A new detection method for ultra-low frequency gravitational waves (GWs) with a frequency much lower than the observational range of pulsar timing arrays (PTAs) was suggested in Yonemaru et al. (2016). In the PTA analysis, ultra-low frequency GWs (≲ 10-10 Hz) which evolve just linearly during the observation time span are absorbed by the pulsar spin-down rates since both have the same effect on the pulse arrival time. Therefore, such GWs cannot be detected by the conventional method of PTAs. However, the bias on the observed spin-down rates depends on relative direction of a pulsar and GW source and shows a quadrupole pattern in the sky. Thus, if we divide the pulsars according to the position in the sky and see the difference in the statistics of the spin-down rates, ultra-low frequency GWs from a single source can be detected. In this paper, we evaluate the potential of this method by Monte-Carlo simulations and estimate the sensitivity, considering only the "Earth term" while the "pulsar term" acts like random noise for GW frequencies 10-13 - 10-10 Hz. We find that with 3,000 milli-second pulsars, which are expected to be discovered by a future survey with the Square Kilometre Array, GWs with the derivative of amplitude of about 3 × 10^{-19} {s}^{-1} can in principle be detected. Implications for possible supermassive binary black holes in Sgr* and M87 are also given.

  15. High-intensity intermittent exercise and its effects on heart rate variability and subsequent strength performance

    Directory of Open Access Journals (Sweden)

    Valéria Leme Gonçalves Panissa

    2016-03-01

    Full Text Available PRUPOSE: To investigate the effects of a 5-km high-intensity interval exercise (HIIE on heart rate variability (HRV and subsequent strength performance. METHODS: nine trained males performed a control session composed of a half-squat strength exercise (4 x 80% of one repetition maximum – 1RM in isolation and 30-min, 1-, 4-, 8- and 24-h after an HIIE (1-min at the velocity peak:1-min passive recovery. All experimental sessions were performed on different days. The maximum number of repetitions and total weight lifted during the strength exercise were registered in all conditions; in addition, prior to each session, HRV were assessed [beat-to-beat intervals (RR and log-transformed of root means square of successive differences in the normal-to-normal intervals (lnRMSSD]. RESULTS: Performance in the strength exercise dropped at 30-min (31% and 1-h (19% post-HIIE concomitantly with lower values of RR (781±79 ms; 799±134 ms, respectively in the same recovery intervals compared to the control (1015±197 ms. Inferential analysis did not detect any effect of condition on lnRMSSD, however, values were lower after 30-min (3.5±0.4 ms and 1-h (3.3±0.5 ms with moderate and large effect sizes (0.9 and 1.2, respectively compared with the control condition (3.9±0.4 ms. CONCLUSION: Both RR and lnRMSSD seem to be associated with deleterious effects on strength performance, although further studies should be conducted to clarify this association.

  16. Performance test of SKIROC II ASIC chip for the radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Jun, W. J.; Namgoong, H.; Kim, B. K.; Song, H. S.; Kim, H. S.; Lee, S. H.; Choi, H. J.; Ghergherehchi, M.; Chai, J. S. [Sungkyunkwan University, Suwon (Korea, Republic of)

    2017-04-15

    There is a PCB board called FEV8 board which can readout analog signal from any energy source, and amplify it for signal processing. For precise detection, the board had been designed to operate in wide range of energy condition, with high-resolutive detection performance. This function has the possibility of the utilization for the radiation detection. The channels of the prototype board must be evaluated to make sure that the board is perfect or not. This research had made an progress for the radiation detection as well as the electronics of the intricate combination of the measurement instrumentations. The number of the noisy channels had been measured for threshold scan, and every channels in the board had been evaluated. By improving the experimental conditions such as test script in Linux system or well designed ground condition of the test bench, much more clean data will be able to be acquisited.

  17. [Evaluation of heart impact in the 100 m extreme intensity sport using near-infrared non-invasive muscle oxygen detecting device and sports heart rate detection technology].

    Science.gov (United States)

    Wang, Pei-Yong; Long, Fei-Xiao; Fu, Lan-Ying; Li, Yue; Ding, Hai-Shu; Qu, An-Lian; Zhou, Xiao-Ping

    2010-02-01

    Using continuous two wavelength near-infrared technology to detect the variation in the consistency of oxygen hemoglobin in the muscle and the sports heart rate wireless real time collection technology, we devised the real time muscle tissue oxygenation and instantaneous heart rate experiment scheme and implemented it for the process of the 100 m run with two parameters given simultaneously. The experiment shows that the concentration of the oxygen hemoglobin in the muscle tissue continues decreasing after the end of the 100 m run, and the time interval between the moment when the concentration of the oxygen hemoglobin attains the minimum value and the moment when the athletes finish the 100 m run is (6.65 +/- 1.10) sec; while the heart rate continues increasing after the end of the 100 m run, and the time interval between the moment when the heart rate attains the maximum value and the moment when the athletes finish the 100 m run is (8.00 +/- 1.57) sec. The results show that the two wavelength near-infrared tissue oxygenation detection technology and the sports heart rate real time collection equipment can accurately measure the sports tissue oxygenation and the heart rate in the extreme intensity sport, and reveal the process of muscle oxygen transportation and consumption and its dynamic character with the heart rate in the extreme intensity sport.

  18. Sentinel lymph node mapping using SPECT/CT and gamma probe in endometrial cancer: an analysis of parameters affecting detection rate

    Energy Technology Data Exchange (ETDEWEB)

    Sahbai, Samine; La Fougere, Christian; Dittmann, Helmut [University Hospital Tuebingen, Nuclear Medicine and Clinical Molecular Imaging, Tuebingen (Germany); Taran, Florin-Andrei; Wallwiener, Diethelm; Brucker, Sara [University Hospital Tuebingen, Gynecology and Obstetrics, Tuebingen (Germany); Staebler, Annette [University Hospital Tuebingen, Pathology, Tuebingen (Germany)

    2017-08-15

    SPECT/CT after pericervical injection of technetium-99 m-nanocolloid was shown to be suitable for sentinel lymph node (SLN) mapping in endometrial cancer (EC). The aim of this study was to analyze factors affecting successful SLN detection by means of SPECT/CT such as imaging findings, patient characteristics and tumor biology in a large cohort of patients. One hundred and forty-five consecutive patients suffering from EC who received pre-surgical SLN mapping at our institution between 2011 and 2016 were included in this analysis. SPECT/CT data of abdomen and pelvis (mean 4:20 ± 1:20 h p.i.) were acquired after pericervical injection of technetium-99 m-nanocolloid (mean 230 ± 45 MBq) in all patients. Surgical staging was performed on the day after. Acquisition parameters, patient characteristics, SPECT/CT findings as well as histopathological results were collected. A total of 282 SLNs were identified by means of SPECT/CT. Overall, preoperative and intraoperative SLN detection rates were 86%, 76% and 74% respectively. The most important factor associated with failure to detect SLNs was the presence of high bone marrow on SPECT/CT (p = 0.005). Peritoneal/abdominal radioactivity was also associated with missed SLN detection in SPECT/CT (p = 0.02). However, the presence of liver/spleen uptake on its own was not predictive for detection failure. Low numbers of detected SLNs in SPECT/CT were slightly related with older age and lower injected activity. No significant influence was found for the parameters of tumor histology and stage, lymph node involvement and the time gap between injection and imaging. Venous drainage as indicated by bone marrow uptake is the most important factor associated with scintigraphic SLN detection failure. Moreover, high peritoneal and abdominal activity was also associated with detection failure. Thus, meticulous application of the radiotracer is crucial in EC. (orig.)

  19. Effect of 2 soccer matches in a week on physical performance and injury rate.

    Science.gov (United States)

    Dupont, Gregory; Nedelec, Mathieu; McCall, Alan; McCormack, Derek; Berthoin, Serge; Wisløff, Ulrik

    2010-09-01

    Recovery duration may be too short during the congested fixtures of professional soccer players with regard to maintaining physical performance and a low injury rate. To analyze the effects of 2 matches per week on physical performance and injury rate in male elite soccer players. Cohort study; Level of evidence, 3. Match results, match-related physical performance, and injuries were monitored during 2 seasons (2007-2008 and 2008-2009) for 32 professional soccer players in a top-level team participating in the UEFA (Union of European Football Associations) Champions League. Total distance, high-intensity distance, sprint distance, and number of sprints were collected for 52 home matches. Injuries and player participation in matches and training were recorded throughout the full season. Physical performance, as characterized by total distance covered, high-intensity distance, sprint distance, and number of sprints, was not significantly affected by the number of matches per week (1 versus 2), whereas the injury rate was significantly higher when players played 2 matches per week versus 1 match per week (25.6 versus 4.1 injuries per 1000 hours of exposure; P physical performance tested but is not long enough to maintain a low injury rate. The present data highlight the need for player rotation and for improved recovery strategies to maintain a low injury rate among athletes during periods with congested match fixtures.

  20. A performance comparison of direct- and indirect-detection flat-panel imagers

    CERN Document Server

    Partridge, M; Müller, L

    2002-01-01

    A comparison of the performance of a direct- and an indirect-detection amorphous silicon flat-panel X-ray imager is presented for a 6 MV beam. Experimental measurements of the noise characteristics, image lag, spectral response, spatial resolution and quantum efficiency are described, compared and discussed. The two systems are comprised of 512x512 pixel, 400 mu m pitch, arrays of a-Si:H p-i-n photodiodes and thin-film transistors. In the direct-detection system, X-rays interact to produce electron/hole pairs directly in the silicon photodiodes. For the indirect-detection system, a phosphor screen converts energy from the incident X-rays into visible light, which is then detected by the photodiodes. Both systems are shown to be quantum noise limited, with the total electronic noise in the detector 10-15 times smaller than the Poisson noise level in detected signal. The measured lag for both systems is 1.0+-0.1% or less in the first frame with subsequent signals decaying exponentially with frame read-out, with...

  1. A Low-Power Wireless Image Sensor Node with Noise-Robust Moving Object Detection and a Region-of-Interest Based Rate Controller

    Science.gov (United States)

    2017-03-01

    from both environment and hardware further reduces the transmission energy with negligible computation and memory overhead. The rate controller...detection, Region-of-interest, Rate control Introduction In wireless image sensor nodes for moving object surveillance, energy efficiency can be...noise, reliable moving object detection is required to avoid unnecessary transmission of background scenes [1]. Transmission energy can be further

  2. Suggestibility and signal detection performance in hallucination-prone students.

    Science.gov (United States)

    Alganami, Fatimah; Varese, Filippo; Wagstaff, Graham F; Bentall, Richard P

    2017-03-01

    Auditory hallucinations are associated with signal detection biases. We examine the extent to which suggestions influence performance on a signal detection task (SDT) in highly hallucination-prone and low hallucination-prone students. We also explore the relationship between trait suggestibility, dissociation and hallucination proneness. In two experiments, students completed on-line measures of hallucination proneness (the revised Launay-Slade Hallucination Scale; LSHS-R), trait suggestibility (Inventory of Suggestibility) and dissociation (Dissociative Experiences Scale-II). Students in the upper and lower tertiles of the LSHS-R performed an auditory SDT. Prior to the task, suggestions were made pertaining to the number of expected targets (Experiment 1, N = 60: high vs. low suggestions; Experiment 2, N = 62, no suggestion vs. high suggestion vs. no voice suggestion). Correlational and regression analyses indicated that trait suggestibility and dissociation predicted hallucination proneness. Highly hallucination-prone students showed a higher SDT bias in both studies. In Experiment 1, both bias scores were significantly affected by suggestions to the same degree. In Experiment 2, highly hallucination-prone students were more reactive to the high suggestion condition than the controls. Suggestions may affect source-monitoring judgments, and this effect may be greater in those who have a predisposition towards hallucinatory experiences.

  3. Performance of target detection algorithm in compressive sensing miniature ultraspectral imaging compressed sensing system

    Science.gov (United States)

    Gedalin, Daniel; Oiknine, Yaniv; August, Isaac; Blumberg, Dan G.; Rotman, Stanley R.; Stern, Adrian

    2017-04-01

    Compressive sensing theory was proposed to deal with the high quantity of measurements demanded by traditional hyperspectral systems. Recently, a compressive spectral imaging technique dubbed compressive sensing miniature ultraspectral imaging (CS-MUSI) was presented. This system uses a voltage controlled liquid crystal device to create multiplexed hyperspectral cubes. We evaluate the utility of the data captured using the CS-MUSI system for the task of target detection. Specifically, we compare the performance of the matched filter target detection algorithm in traditional hyperspectral systems and in CS-MUSI multiplexed hyperspectral cubes. We found that the target detection algorithm performs similarly in both cases, despite the fact that the CS-MUSI data is up to an order of magnitude less than that in conventional hyperspectral cubes. Moreover, the target detection is approximately an order of magnitude faster in CS-MUSI data.

  4. A new islanding detection technique for multiple mini hydro based on rate of change of reactive power and load connecting strategy

    International Nuclear Information System (INIS)

    Laghari, J.A.; Mokhlis, H.; Bakar, A.H.A.; Karimi, M.

    2013-01-01

    Highlights: • The requirement of DG interconnection with existing power system is discussed. • Various islanding detection techniques are discussed with their merits and demerits. • New islanding detection strategy is proposed for multiple mini hydro type DGs. • The proposed strategy is based on dq/dt and load connecting strategy. • The effectiveness of strategy is verified on various other cases. - Abstract: The interconnection of distributed generation (DG) into distribution networks is undergoing a rapid global expansion. It enhances the system’s reliability, while simultaneously reduces pollution problems related to the generation of electrical power. To fully utilize the benefits of DGs, certain technical issues need to be addressed. One of the most important issues in this context is islanding detection. This paper presents a new islanding detection technique that is suitable for multiple mini-hydro type DG units. The proposed strategy is based on the rate of change of reactive power and load connecting strategy to detect islanding within the system. For a large power mismatch, islanding is detected by rate of change of reactive power only. However, for a close power mismatch, the rate of change of reactive power initiates a load connecting strategy, which in turn alters the load on the distribution network. This load variation in the distribution network causes a variation in the rate of change of reactive power, which is utilized to distinguish islanding and other events. The simulation results show that the proposed strategy is effective in detecting islanding occurrence in a distribution network

  5. Performance evaluation and modeling of a conformal filter (CF) based real-time standoff hazardous material detection sensor

    Science.gov (United States)

    Nelson, Matthew P.; Tazik, Shawna K.; Bangalore, Arjun S.; Treado, Patrick J.; Klem, Ethan; Temple, Dorota

    2017-05-01

    Hyperspectral imaging (HSI) systems can provide detection and identification of a variety of targets in the presence of complex backgrounds. However, current generation sensors are typically large, costly to field, do not usually operate in real time and have limited sensitivity and specificity. Despite these shortcomings, HSI-based intelligence has proven to be a valuable tool, thus resulting in increased demand for this type of technology. By moving the next generation of HSI technology into a more adaptive configuration, and a smaller and more cost effective form factor, HSI technologies can help maintain a competitive advantage for the U.S. armed forces as well as local, state and federal law enforcement agencies. Operating near the physical limits of HSI system capability is often necessary and very challenging, but is often enabled by rigorous modeling of detection performance. Specific performance envelopes we consistently strive to improve include: operating under low signal to background conditions; at higher and higher frame rates; and under less than ideal motion control scenarios. An adaptable, low cost, low footprint, standoff sensor architecture we have been maturing includes the use of conformal liquid crystal tunable filters (LCTFs). These Conformal Filters (CFs) are electro-optically tunable, multivariate HSI spectrometers that, when combined with Dual Polarization (DP) optics, produce optimized spectral passbands on demand, which can readily be reconfigured, to discriminate targets from complex backgrounds in real-time. With DARPA support, ChemImage Sensor Systems (CISS™) in collaboration with Research Triangle Institute (RTI) International are developing a novel, real-time, adaptable, compressive sensing short-wave infrared (SWIR) hyperspectral imaging technology called the Reconfigurable Conformal Imaging Sensor (RCIS) based on DP-CF technology. RCIS will address many shortcomings of current generation systems and offer improvements in

  6. Detection of auditory signals in quiet and noisy backgrounds while performing a visuo-spatial task

    Directory of Open Access Journals (Sweden)

    Vishakha W Rawool

    2016-01-01

    Full Text Available Context: The ability to detect important auditory signals while performing visual tasks may be further compounded by background chatter. Thus, it is important to know how task performance may interact with background chatter to hinder signal detection. Aim: To examine any interactive effects of speech spectrum noise and task performance on the ability to detect signals. Settings and Design: The setting was a sound-treated booth. A repeated measures design was used. Materials and Methods: Auditory thresholds of 20 normal adults were determined at 0.5, 1, 2 and 4 kHz in the following conditions presented in a random order: (1 quiet with attention; (2 quiet with a visuo-spatial task or puzzle (distraction; (3 noise with attention and (4 noise with task. Statistical Analysis: Multivariate analyses of variance (MANOVA with three repeated factors (quiet versus noise, visuo-spatial task versus no task, signal frequency. Results: MANOVA revealed significant main effects for noise and signal frequency and significant noise–frequency and task–frequency interactions. Distraction caused by performing the task worsened the thresholds for tones presented at the beginning of the experiment and had no effect on tones presented in the middle. At the end of the experiment, thresholds (4 kHz were better while performing the task than those obtained without performing the task. These effects were similar across the quiet and noise conditions. Conclusion: Detection of auditory signals is difficult at the beginning of a distracting visuo-spatial task but over time, task learning and auditory training effects can nullify the effect of distraction and may improve detection of high frequency sounds.

  7. Performance of Narrowband Signal Detection under Correlated Rayleigh Fading Based on Synthetic Array

    Directory of Open Access Journals (Sweden)

    Ali Broumandan

    2009-01-01

    design parameters of probability of detection (Pd and probability of false alarm (Pfa. An optimum detector based on Estimator-Correlator (EC is developed, and its performance is compared with that of suboptimal Equal-Gain (EG combiner in different channel correlation scenarios. It is shown that in moderate channel correlation scenarios the detection performance of EC and EG is identical. The sensitivity of the proposed method to knowledge of motion parameters is also investigated. An extensive set of measurements based on CDMA-2000 pilot signals using the static antenna and synthetic array are used to experimentally verify these theoretical findings.

  8. A simple optimization can improve the performance of single feature polymorphism detection by Affymetrix expression arrays

    Directory of Open Access Journals (Sweden)

    Fujisawa Hironori

    2010-05-01

    Full Text Available Abstract Background High-density oligonucleotide arrays are effective tools for genotyping numerous loci simultaneously. In small genome species (genome size: Results We compared the single feature polymorphism (SFP detection performance of whole-genome and transcript hybridizations using the Affymetrix GeneChip® Rice Genome Array, using the rice cultivars with full genome sequence, japonica cultivar Nipponbare and indica cultivar 93-11. Both genomes were surveyed for all probe target sequences. Only completely matched 25-mer single copy probes of the Nipponbare genome were extracted, and SFPs between them and 93-11 sequences were predicted. We investigated optimum conditions for SFP detection in both whole genome and transcript hybridization using differences between perfect match and mismatch probe intensities of non-polymorphic targets, assuming that these differences are representative of those between mismatch and perfect targets. Several statistical methods of SFP detection by whole-genome hybridization were compared under the optimized conditions. Causes of false positives and negatives in SFP detection in both types of hybridization were investigated. Conclusions The optimizations allowed a more than 20% increase in true SFP detection in whole-genome hybridization and a large improvement of SFP detection performance in transcript hybridization. Significance analysis of the microarray for log-transformed raw intensities of PM probes gave the best performance in whole genome hybridization, and 22,936 true SFPs were detected with 23.58% false positives by whole genome hybridization. For transcript hybridization, stable SFP detection was achieved for highly expressed genes, and about 3,500 SFPs were detected at a high sensitivity (> 50% in both shoot and young panicle transcripts. High SFP detection performances of both genome and transcript hybridizations indicated that microarrays of a complex genome (e.g., of Oryza sativa can be

  9. Operator performance in non-destructive testing: A study of operator performance in a performance test

    Energy Technology Data Exchange (ETDEWEB)

    Enkvist, J.; Edland, A.; Svenson, Ola [Stockholm Univ. (Sweden). Dept. of Psychology

    2000-05-15

    In the process industries there is a need of inspecting the integrity of critical components without disrupting the process. Such in-service inspections are typically performed with non-destructive testing (NDT). In NDT the task of the operator is to (based on diagnostic information) decide if the component can remain in service or not. The present study looks at the performance in NDT. The aim is to improve performance, in the long run, by exploring the operators' decision strategies and other underlying factors and to this way find out what makes some operators more successful than others. Sixteen operators performed manual ultrasonic inspections of four test pieces with the aim to detect (implanted) cracks. In addition to these performance demonstration tests (PDT), the operators performed independent ability tests and filled out questionnaires. The results show that operators who trust their gut feeling more than the procedure (when the two come to different results) and that at the same time have a positive attitude towards the procedure have a higher PDT performance. These results indicate the need for operators to be motivated and confident when performing NDT. It was also found that the operators who performed better rated more decision criteria higher in the detection phase than the operators who performed worse. For characterizing it was the other way around. Also, the operators who performed better used more time, both detecting and characterizing, than the operators who performed worse.

  10. Operator performance in non-destructive testing: A study of operator performance in a performance test

    International Nuclear Information System (INIS)

    Enkvist, J.; Edland, A.; Svenson, Ola

    2000-05-01

    In the process industries there is a need of inspecting the integrity of critical components without disrupting the process. Such in-service inspections are typically performed with non-destructive testing (NDT). In NDT the task of the operator is to (based on diagnostic information) decide if the component can remain in service or not. The present study looks at the performance in NDT. The aim is to improve performance, in the long run, by exploring the operators' decision strategies and other underlying factors and to this way find out what makes some operators more successful than others. Sixteen operators performed manual ultrasonic inspections of four test pieces with the aim to detect (implanted) cracks. In addition to these performance demonstration tests (PDT), the operators performed independent ability tests and filled out questionnaires. The results show that operators who trust their gut feeling more than the procedure (when the two come to different results) and that at the same time have a positive attitude towards the procedure have a higher PDT performance. These results indicate the need for operators to be motivated and confident when performing NDT. It was also found that the operators who performed better rated more decision criteria higher in the detection phase than the operators who performed worse. For characterizing it was the other way around. Also, the operators who performed better used more time, both detecting and characterizing, than the operators who performed worse

  11. INTEREST RATE REGIME AND THE PERFORMANCE OF THE NIGERIAN CAPITAL MARKET

    Directory of Open Access Journals (Sweden)

    Edirin Jeroh

    2015-12-01

    Full Text Available This study x-ray’s the interest rates regime in Nigeria as it affects the performance of the Nigerian Capital Market. In order to achieve this objective, relevant data for a period of 33 years spanning from 1981 – 2013 were obtained from the Factbook of the Nigerian Stock Exchange, CBN Statistical Bulletin as well as the annual accounts of quoted firms for the relevant years. The data obtained were analysed with the Ordinary Least Square (OLS technique. The result from our analysis reveal among others that changes in interest rate regimes have majorly influenced the level of the performance of the Nigerian Capital Market. Based on the above, we recommend that capital market regulators and other regulatory agencies should keep an eye on movements in interest rates and the Minimum Rediscount Rate (MRR (now MPR and watch their trend. We also recommend that efforts must be put in place to establish a policy review and reassessment mechanism that would help in assessing the impact of selected policy measures on the economy so that policy makers would know the effectiveness and efficiency of designed policies and be guided in the policy review and development process in the country.

  12. Validation of an automated seizure detection algorithm for term neonates

    Science.gov (United States)

    Mathieson, Sean R.; Stevenson, Nathan J.; Low, Evonne; Marnane, William P.; Rennie, Janet M.; Temko, Andrey; Lightbody, Gordon; Boylan, Geraldine B.

    2016-01-01

    Objective The objective of this study was to validate the performance of a seizure detection algorithm (SDA) developed by our group, on previously unseen, prolonged, unedited EEG recordings from 70 babies from 2 centres. Methods EEGs of 70 babies (35 seizure, 35 non-seizure) were annotated for seizures by experts as the gold standard. The SDA was tested on the EEGs at a range of sensitivity settings. Annotations from the expert and SDA were compared using event and epoch based metrics. The effect of seizure duration on SDA performance was also analysed. Results Between sensitivity settings of 0.5 and 0.3, the algorithm achieved seizure detection rates of 52.6–75.0%, with false detection (FD) rates of 0.04–0.36 FD/h for event based analysis, which was deemed to be acceptable in a clinical environment. Time based comparison of expert and SDA annotations using Cohen’s Kappa Index revealed a best performing SDA threshold of 0.4 (Kappa 0.630). The SDA showed improved detection performance with longer seizures. Conclusion The SDA achieved promising performance and warrants further testing in a live clinical evaluation. Significance The SDA has the potential to improve seizure detection and provide a robust tool for comparing treatment regimens. PMID:26055336

  13. Breast cancer detection rates using four different types of mammography detectors

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, Alistair; Warren, Lucy M.; Dance, David R.; Young, Kenneth C. [Royal Surrey County Hospital, National Coordinating Centre for the Physics in Mammography (NCCPM), Guildford (United Kingdom); University of Surrey, Department of Physics, Guildford (United Kingdom); Wallis, Matthew G. [Cambridge University Hospitals NHS Foundation Trust, Cambridge (United Kingdom); NIHR Cambridge Biomedical Research Centre, Cambridge Breast Unit, Cambridge (United Kingdom); Cooke, Julie [Jarvis Breast Screening and Diagnostic Centre, Guildford (United Kingdom); Given-Wilson, Rosalind M. [St George' s Healthcare NHS Trust, Department of Radiology, London (United Kingdom); Chakraborty, Dev P. [University of Pittsburgh, Department of Radiology, Pittsburgh, PA (United States); Halling-Brown, Mark D. [Royal Surrey County Hospital, Scientific Computing, Department of Medical Physics, Guildford (United Kingdom); Looney, Padraig T. [Royal Surrey County Hospital, National Coordinating Centre for the Physics in Mammography (NCCPM), Guildford (United Kingdom)

    2016-03-15

    To compare the performance of different types of detectors in breast cancer detection. A mammography image set containing subtle malignant non-calcification lesions, biopsy-proven benign lesions, simulated malignant calcification clusters and normals was acquired using amorphous-selenium (a-Se) detectors. The images were adapted to simulate four types of detectors at the same radiation dose: digital radiography (DR) detectors with a-Se and caesium iodide (CsI) convertors, and computed radiography (CR) detectors with a powder phosphor (PIP) and a needle phosphor (NIP). Seven observers marked suspicious and benign lesions. Analysis was undertaken using jackknife alternative free-response receiver operating characteristics weighted figure of merit (FoM). The cancer detection fraction (CDF) was estimated for a representative image set from screening. No significant differences in the FoMs between the DR detectors were measured. For calcification clusters and non-calcification lesions, both CR detectors' FoMs were significantly lower than for DR detectors. The calcification cluster's FoM for CR NIP was significantly better than for CR PIP. The estimated CDFs with CR PIP and CR NIP detectors were up to 15 % and 22 % lower, respectively, than for DR detectors. Cancer detection is affected by detector type, and the use of CR in mammography should be reconsidered. (orig.)

  14. Bayesian image reconstruction for improving detection performance of muon tomography.

    Science.gov (United States)

    Wang, Guobao; Schultz, Larry J; Qi, Jinyi

    2009-05-01

    Muon tomography is a novel technology that is being developed for detecting high-Z materials in vehicles or cargo containers. Maximum likelihood methods have been developed for reconstructing the scattering density image from muon measurements. However, the instability of maximum likelihood estimation often results in noisy images and low detectability of high-Z targets. In this paper, we propose using regularization to improve the image quality of muon tomography. We formulate the muon reconstruction problem in a Bayesian framework by introducing a prior distribution on scattering density images. An iterative shrinkage algorithm is derived to maximize the log posterior distribution. At each iteration, the algorithm obtains the maximum a posteriori update by shrinking an unregularized maximum likelihood update. Inverse quadratic shrinkage functions are derived for generalized Laplacian priors and inverse cubic shrinkage functions are derived for generalized Gaussian priors. Receiver operating characteristic studies using simulated data demonstrate that the Bayesian reconstruction can greatly improve the detection performance of muon tomography.

  15. Real-time detection with AdaBoost-svm combination in various face orientation

    Science.gov (United States)

    Fhonna, R. P.; Nasution, M. K. M.; Tulus

    2018-03-01

    Most of the research has used algorithm AdaBoost-SVM for face detection. However, to our knowledge so far there is no research has been facing detection on real-time data with various orientations using the combination of AdaBoost and Support Vector Machine (SVM). Characteristics of complex and diverse face variations and real-time data in various orientations, and with a very complex application will slow down the performance of the face detection system this becomes a challenge in this research. Face orientation performed on the detection system, that is 900, 450, 00, -450, and -900. This combination method is expected to be an effective and efficient solution in various face orientations. The results showed that the highest average detection rate is on the face detection oriented 00 and the lowest detection rate is in the face orientation 900.

  16. Effect of feeding frequency and feeding rate on growth performance ...

    African Journals Online (AJOL)

    Fish fed at higher feeding rates accumulated significantly more lipid within the body and had associated decreases in moisture, protein, and ash content, but carcass composition was unaffected by feeding frequency. Juvenile pompano show better growth performance when fed 10% BW/day 3 and 6 times a day.

  17. Influence of depth, time and human activity on detection rate of acoustic tags: a case study on two fish farms.

    Science.gov (United States)

    Otterå, H; Skilbrei, O T

    2016-03-01

    The detection rates of stationary acoustic transmitters deployed at three depths on two Atlantic salmon Salmo salar cage farms for c. 2 months were investigated. Deployment depth, time of day, day of the year and specific incidences at the farm substantially affected the rate of signal detection by the receiver. © 2016 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

  18. Visual performance on detection tasks with double-targets of the same and different difficulty.

    Science.gov (United States)

    Chan, Alan H S; Courtney, Alan J; Ma, C W

    2002-10-20

    This paper reports a study of measurement of horizontal visual sensitivity limits for 16 subjects in single-target and double-targets detection tasks. Two phases of tests were conducted in the double-targets task; targets of the same difficulty were tested in phase one while targets of different difficulty were tested in phase two. The range of sensitivity for the double-targets test was found to be smaller than that for single-target in both the same and different target difficulty cases. The presence of another target was found to affect performance to a marked degree. Interference effect of the difficult target on detection of the easy one was greater than that of the easy one on the detection of the difficult one. Performance decrement was noted when correct percentage detection was plotted against eccentricity of target in both the single-target and double-targets tests. Nevertheless, the non-significant correlation found between the performance for the two tasks demonstrated that it was impossible to predict quantitatively ability for detection of double targets from the data for single targets. This indicated probable problems in generalizing data for single target visual lobes to those for multiple targets. Also lobe area values obtained from measurements using a single-target task cannot be applied in a mathematical model for situations with multiple occurrences of targets.

  19. Probabilistic pipe fracture evaluations for applications to leak-rate detection

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, S; Wilkowski, G; Ghadiali, N [Battelle Columbus Labs., OH (United States)

    1993-12-31

    Stochastic pipe fracture evaluations are conducted for applications to leak-rate detection. A state-of-the-art review was first conducted to evaluate the adequacy of current deterministic models for thermo-hydraulic and elastic-plastic fracture analyses. Then a new probabilistic model was developed with the above deterministic models for structural reliability analysis of cracked piping systems and statistical characterization of crack morphology parameters, material properties of pipe, and crack location. The proposed models are then applied for computing conditional probability of failure for various nuclear piping systems in BWR and PWR plants. The PRAISE code was not used, and the probabilistic model is based on modern methods of stochastic mechanics, computationally far superior to Monte Carlo and Stratified Sampling methods used in PRAISE. 10 refs., 9 figs., 1 tab.

  20. Probabilistic pipe fracture evaluations for applications to leak-rate detection

    International Nuclear Information System (INIS)

    Rahman, S.; Wilkowski, G.; Ghadiali, N.

    1992-01-01

    Stochastic pipe fracture evaluations are conducted for applications to leak-rate detection. A state-of-the-art review was first conducted to evaluate the adequacy of current deterministic models for thermo-hydraulic and elastic-plastic fracture analyses. Then a new probabilistic model was developed with the above deterministic models for structural reliability analysis of cracked piping systems and statistical characterization of crack morphology parameters, material properties of pipe, and crack location. The proposed models are then applied for computing conditional probability of failure for various nuclear piping systems in BWR and PWR plants. The PRAISE code was not used, and the probabilistic model is based on modern methods of stochastic mechanics, computationally far superior to Monte Carlo and Stratified Sampling methods used in PRAISE. 10 refs., 9 figs., 1 tab

  1. A Computationally Intelligent Approach to the Detection of Wormhole Attacks in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mohammad Nurul Afsar Shaon

    2017-05-01

    Full Text Available A wormhole attack is one of the most critical and challenging security threats for wireless sensor networks because of its nature and ability to perform concealed malicious activities. This paper proposes an innovative wormhole detection scheme to detect wormhole attacks using computational intelligence and an artificial neural network (ANN. Most wormhole detection schemes reported in the literature assume the sensors are uniformly distributed in a network, and, furthermore, they use statistical and topological information and special hardware for their detection. However, these schemes may perform poorly in non-uniformly distributed networks, and, moreover, they may fail to defend against “out of band” and “in band” wormhole attacks. The aim of the proposed research is to develop a detection scheme that is able to detect all kinds of wormhole attacks in both uniformly and non-uniformly distributed sensor networks. Furthermore, the proposed research does not require any special hardware and causes no significant network overhead throughout the network. Most importantly, the probable location of the malicious nodes can be identified by the proposed ANN based detection scheme. We evaluate the efficacy of the proposed detection scheme in terms of detection accuracy, false positive rate, and false negative rate. The performance of the proposed algorithm is also compared with other machine learning techniques (i.e. SVM and regularized nonlinear logistic regression (LR based detection models. The simulation results show that proposed ANN based algorithm outperforms the SVM or LR based detection schemes in terms of detection accuracy, false positive rate, and false negative rates.

  2. 3D versus 2D Systematic Transrectal Ultrasound-Guided Prostate Biopsy: Higher Cancer Detection Rate in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Alexandre Peltier

    2013-01-01

    Full Text Available Objectives. To compare prostate cancer detection rates of extended 2D versus 3D biopsies and to further assess the clinical impact of this method in day-to-day practice. Methods. We analyzed the data of a cohort of 220 consecutive patients with no prior history of prostate cancer who underwent an initial prostate biopsy in daily practice due to an abnormal PSA and/or DRE using, respectively, the classical 2D and the new 3D systems. All the biopsies were done by a single experienced operator using the same standardized protocol. Results. There was no significant difference in terms of age, total PSA, or prostate volume between the two groups. However, cancer detection rate was significantly higher using the 3D versus the 2D system, 50% versus 34% (P<0.05. There was no statistically significant difference while comparing the 2 groups in term of nonsignificant cancer detection. Conclusion. There is reasonable evidence demonstrating the superiority of the 3D-guided biopsies in detecting prostate cancers that would have been missed using the 2D extended protocol.

  3. Samsung Salmonella Detection Kit. AOAC Performance Tested Method(SM) 021203.

    Science.gov (United States)

    Li, Jun; Cheung, Win Den; Opdyke, Jason; Harvey, John; Chong, Songchun; Moon, Cheol Gon

    2012-01-01

    Salmonella, one of the most common causes of foodborne illness, is a significant public health concern worldwide. There is a need in the food industry for methods that are simple, rapid, and sensitive for the detection of foodborne pathogens. In this study, the Samsung Salmonella Detection Kit, a real-time PCR assay for the detection of Salmonella, was evaluated according to the current AOAC guidelines. The validation consisted of lot-to-lot consistency, stability, robustness, and inclusivity/exclusivity studies, as well as a method comparison of 10 different food matrixes. In the validation, the Samsung Salmonella Detection Kit was used in conjunction with the Applied Biosystems StepOnePlus PCR system and the Samsung Food Testing Software for the detection of Salmonella species. The performance of the assays was compared to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG) 4.05: Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg, and Catfish and the and U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference methods. The validation was conducted using an unpaired study design for detection of Salmonella spp. in raw ground beef, raw pork, raw ground pork, raw chicken wings, raw salmon, alfalfa sprouts, pasteurized orange juice, peanut butter, pasteurized whole milk, and shell eggs. The Samsung Salmonella Detection Kit demonstrated lot-to-lot consistency among three independent lots as well as ruggedness with minor modifications to changes in enrichment incubation time, enrichment incubation temperature, and DNA sample volume for PCR reaction. Stability was observed for 13 months at -20 degrees C and 3 months at 5 degrees C. For the inclusivity/exclusivity study, the Samsung Salmonella Detection Kit correctly identified 147 Salmonella species isolates out of 147 isolates tested from each of three different enrichment

  4. A novel hardware implementation for detecting respiration rate using photoplethysmography.

    Science.gov (United States)

    Prinable, Joseph; Jones, Peter; Thamrin, Cindy; McEwan, Alistair

    2017-07-01

    Asthma is a serious public health problem. Continuous monitoring of breathing may offer an alternative way to assess disease status. In this paper we present a novel hardware implementation for the capture and storage of a photoplethysmography (PPG) signal. The LED duty cycle was altered to determine the effect on respiratory rate accuracy. The oximeter was mounted to the left index finger of ten healthy volunteers. The breathing rate derived from the oximeter was validated against a nasal airflow sensor. The duty cycle of a pulse oximeter was changed between 5%, 10% and 25% at a sample rate of 500 Hz. A PPG signal and reference signal was captured for each duty cycle. The PPG signals were post processed in Matlab to derive a respiration rate using an existing Matlab toolbox. At a 25% duty cycle the RMSE was <;2 breaths per minute for the top performing algorithm. The RMSE increased to over 5 breaths per minute when the duty cycle was reduced to 5%. The power consumed by the hardware for a 5%, 10% and 25% duty cycle was 5.4 mW, 7.8 mW, and 15 mW respectively. For clinical assessment of respiratory rate, a RSME of <;2 breaths per minute is recommended. Further work is required to determine utility in asthma management. However for non-clinical applications such as fitness tracking, lower accuracy may be sufficient to allow a reduced duty cycle setting.

  5. How should low-contrast detail detectability be measured in fluoroscopy?

    International Nuclear Information System (INIS)

    Tapiovaara, Markku J.; Sandborg, Michael

    2004-01-01

    The relationship and precision of four methods for measuring the low-contrast detail detectability in fluoroscopic imaging were studied. These included the physical measurement of the accumulation rate of the square of the signal-to-noise ratio (SNR rate 2 ), two-alternative forced-choice (2-AFC) experiments, sixteen-alternative forced-choice (16-AFC) experiments and subjective determination of the threshold contrast. The precision and sensitivity of the threshold contrast measurement were seen to be modest in the constancy testing of fluoroscopic equipment: only large changes in system performance could be reliably detected by that method. The measurement of the SNR rate 2 is suggested instead. The relationship between the results of the various methods were studied, and it was found that human performance can be related to SNR rate 2 by introducing the concept of the effective image information integration time (t eff ). When measured for an unlimited observation time, it depicts the saturation of human performance in detecting a static low-contrast detail in dynamic image noise. Here, t eff was found to be about 0.6 s in 2-AFC tests and 0.3 s in 16-AFC tests

  6. Effective Rating Scale Development for Speaking Tests: Performance Decision Trees

    Science.gov (United States)

    Fulcher, Glenn; Davidson, Fred; Kemp, Jenny

    2011-01-01

    Rating scale design and development for testing speaking is generally conducted using one of two approaches: the measurement-driven approach or the performance data-driven approach. The measurement-driven approach prioritizes the ordering of descriptors onto a single scale. Meaning is derived from the scaling methodology and the agreement of…

  7. Astrophysical limitations to the identification of dark matter: Indirect neutrino signals vis-a-vis direct detection recoil rates

    International Nuclear Information System (INIS)

    Serpico, Pasquale D.; Bertone, Gianfranco

    2010-01-01

    A convincing identification of dark matter (DM) particles can probably be achieved only through a combined analysis of different detections strategies, which provides an effective way of removing degeneracies in the parameter space of DM models. In practice, however, this program is made complicated by the fact that different strategies depend on different physical quantities, or on the same quantities but in a different way, making the treatment of systematic errors rather tricky. We discuss here the uncertainties on the recoil rate in direct-detection experiments and on the muon rate induced by neutrinos from dark matter annihilations in the Sun, and we show that, contrarily to the local DM density or overall cross section scale, irreducible astrophysical uncertainties affect the two rates in a different fashion, therefore limiting our ability to reconstruct the parameters of the dark matter particles. By varying within their respective errors astrophysical parameters such as the escape velocity and the velocity dispersion of dark matter particles, we show that the uncertainty on the relative strength of the neutrino and direct-detection signal is as large as a factor of 2 for typical values of the parameters, but can be even larger in some circumstances.

  8. Evaluating cessation of the type 2 oral polio vaccine by modeling pre- and post-cessation detection rates.

    Science.gov (United States)

    Kroiss, Steve J; Famulare, Michael; Lyons, Hil; McCarthy, Kevin A; Mercer, Laina D; Chabot-Couture, Guillaume

    2017-10-09

    The globally synchronized removal of the attenuated Sabin type 2 strain from the oral polio vaccine (OPV) in April 2016 marked a major change in polio vaccination policy. This change will provide a significant reduction in the burden of vaccine-associated paralytic polio (VAPP), but may increase the risk of circulating vaccine-derived poliovirus (cVDPV2) outbreaks during the transition period. This risk can be monitored by tracking the disappearance of Sabin-like type 2 (SL2) using data from the polio surveillance system. We studied SL2 prevalence in 17 countries in Africa and Asia, from 2010 to 2016 using acute flaccid paralysis surveillance data. We modeled the peak and decay of SL2 prevalence following mass vaccination events using a beta-binomial model for the detection rate, and a Ricker function for the temporal dependence. We found type 2 circulated the longest of all serotypes after a vaccination campaign, but that SL2 prevalence returned to baseline levels in approximately 50days. Post-cessation model predictions identified 19 anomalous SL2 detections outside of model predictions in Afghanistan, India, Nigeria, Pakistan, and western Africa. Our models established benchmarks for the duration of SL2 detection after OPV2 cessation. As predicted, SL2 detection rates have plummeted, except in Nigeria where OPV2 use continued for some time in response to recent cVDPV2 detections. However, the anomalous SL2 detections suggest specific areas that merit enhanced monitoring for signs of cVDPV2 outbreaks. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. Orchestra Festival Evaluations: Interjudge Agreement and Relationships between Performance Categories and Final Ratings.

    Science.gov (United States)

    Garman, Barry R.; And Others

    1991-01-01

    Band, orchestra, and choir festival evaluations are a regular part of many secondary school music programs, and most such festivals engage adjudicators who rate each group's performance. Because music ensemble performance is complex and multi-dimensional, it does not lend itself readily to precise measurement; generally, musical performances are…

  10. Analysis of acoustic cardiac signals for heart rate variability and murmur detection using nonnegative matrix factorization-based hierarchical decomposition

    DEFF Research Database (Denmark)

    Shah, Ghafoor; Koch, Peter; Papadias, Constantinos B.

    2014-01-01

    The detection of heart rate variability (HRV) via cardiac auscultation examination can be a useful and inexpensive tool which, however, is challenging in the presence of pathological signals and murmurs. The aim of this research is to analyze acoustic cardiac signals for HRV and murmur detection...

  11. Modelling the imaging performance and low contrast detectability in digital mammography

    International Nuclear Information System (INIS)

    Spyropoulou, V; Kalyvas, N; Gaitanis, A; Michail, C; Panayiotakis, G; Kandarakis, I

    2009-01-01

    A digital x-ray mammography is a modern method for the early detection of breast cancer. The quality of a mammography image depends on various factors, the detector structure and performance being of primary importance. The aim of this work was to develop an analytical model simulating the imaging performance of a new commercially available digital mammography detector. This was achieved within the framework of the linear cascaded systems (LCS) theory. System analysis has allowed the estimation of important image quality metrics such as the Modulation Transfer Function (MTF), the Noise Power Spectrum (NPS) and the Detective Quantum Efficiency (DQE). The detector was an indirect detection system consisting of a large area, 100μm thick, CsI:TI scintillator coupled to an active matrix array of amorphous silicon (a-Si:H) photodiodes combined with thin film transistors (TFT). Pixel size was 100μm, while the active pixel dimension was 70μm. MTF and DQE data were calculated for air kerma conditions of 25, 53, 67 μGy using a 28 kVp Mo-Mo x-ray spectrum. The theoretical results were compared with published experimental data. The deviation between the theoretical and experimental MTF curves was less than 4%, while the DQE differences were found at an acceptable level. The model was also used to estimate system's capability to detect low contrast objects in the breast. It was estimated that, in the breast gland, low contrast structures larger than 1.4mm can be adequately identified by the above system.

  12. WO{sub 3-x} rate at Au rate at MnO{sub 2} core-shell nanowires on carbon fabric for high-performance flexible supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xihong; Zhai, Teng [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou (China); Zhang, Xianghui; Shen, Yongqi; Yuan, Longyan; Hu, Bin; Gao, Yihua; Zhou, Jun [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); Gong, Li; Chen, Jian [Instrumental Analysis and Research Center, Sun Yat-sen University, Guangzhou (China); Tong, Yexiang [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou (China); Wang, Zhong Lin [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia (United States)

    2012-02-14

    WO{sub 3-x} rate at Au rate at MnO{sub 2} core-shell nanowires (NWs) are synthesized on a flexible carbon fabric and show outstanding electrochemical performance in supercapacitors such as high specific capacitance, good cyclic stability, high energy density, and high power density. These results suggest that the WO{sub 3-x} rate at Au rate at MnO{sub 2} NWs have promising potential for use in high-performance flexible supercapacitors. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Performances of Four Helicobacter pylori Serological Detection Kits Using Stool Antigen Test as Gold Standard.

    Directory of Open Access Journals (Sweden)

    Susheela D Biranjia-Hurdoyal

    Full Text Available The aim was to determine the performances of four Helicobacter pylori serological detection kits in different target groups, using Amplified IDEIA™ Hp StAR™ as gold standard. Kits studied were Rapid Immunochromatoghraphic Hexagon, Helicoblot 2.1, an EIA IgG kit and EIA IgA kit.Stool and blood samples were collected from 162 apparently healthy participants (control and 60 Type 2 diabetes mellitus (T2DM patients.The performances of the four serological detection kits were found to be affected by gender, age, health status and ethnicity of the participants. In the control group, the Helicoblot 2.1 kit had the best performance (AUC = 0.85; p<0.05, accuracy = 86.4%, followed by EIA IgG (AUC = 0.75; p<0.05, accuracy = 75.2%. The Rapid Hexagon and EIA IgA kits had relatively poor performances. In the T2DM subgroup, the kits H2.1 and EIA IgG had best performances, with accuracies of 96.5% and 93.1% respectively. The performance of EIA IgG improved with adjustment of its cut-off value.The performances of the detection kits were affected by various factors which should be taken into consideration.

  14. Classifier models and architectures for EEG-based neonatal seizure detection

    International Nuclear Information System (INIS)

    Greene, B R; Marnane, W P; Lightbody, G; Reilly, R B; Boylan, G B

    2008-01-01

    Neonatal seizures are the most common neurological emergency in the neonatal period and are associated with a poor long-term outcome. Early detection and treatment may improve prognosis. This paper aims to develop an optimal set of parameters and a comprehensive scheme for patient-independent multi-channel EEG-based neonatal seizure detection. We employed a dataset containing 411 neonatal seizures. The dataset consists of multi-channel EEG recordings with a mean duration of 14.8 h from 17 neonatal patients. Early-integration and late-integration classifier architectures were considered for the combination of information across EEG channels. Three classifier models based on linear discriminants, quadratic discriminants and regularized discriminants were employed. Furthermore, the effect of electrode montage was considered. The best performing seizure detection system was found to be an early integration configuration employing a regularized discriminant classifier model. A referential EEG montage was found to outperform the more standard bipolar electrode montage for automated neonatal seizure detection. A cross-fold validation estimate of the classifier performance for the best performing system yielded 81.03% of seizures correctly detected with a false detection rate of 3.82%. With post-processing, the false detection rate was reduced to 1.30% with 59.49% of seizures correctly detected. These results represent a comprehensive illustration that robust reliable patient-independent neonatal seizure detection is possible using multi-channel EEG

  15. The Performance of the Four Anaerobic Blood Culture Bottles BacT/ALERT-FN, -FN Plus, BACTEC-Plus and -Lytic in Detection of Anaerobic Bacteria and Identification by Direct MALDI-TOF MS.

    Directory of Open Access Journals (Sweden)

    Mohammed Almuhayawi

    Full Text Available Detection and identification of anaerobic bacteria in blood cultures (BC is a well-recognized challenge in clinical microbiology. We studied 100 clinical anaerobic BC isolates to evaluate the performance of BacT/ALERT-FN, -FN Plus (BioMérieux, BACTEC-Plus and -Lytic (Becton Dickinson BioSciences BC bottles in detection and time to detection (TTD of anaerobic bacteria. BACTEC Lytic had higher detection rate (94/100, 94% than BacT/ALERT FN Plus (80/100, 80% (p<0.01 in the studied material. There was no significant difference in detection of anaerobic bacteria among the remaining bottle types. The 67 anaerobic bacteria that signalled positive in all four bottle types were analyzed to compare the time to detection (TTD and isolates were directly identified by MALDI-TOF MS. There was a significant difference in TTD among the four bottle types (p<0.0001. The shortest median TTD was 18 h in BACTEC Lytic followed by BacT/ALERT FN (23.5 h, BACTEC Plus (27 h and finally BacT/ALERT FN Plus (38 h bottles. In contrast, MALDI-TOF MS performed similarly in all bottle types with accurate identification in 51/67 (76% BacT/ALERT FN, 51/67 (76% BacT/ALERT FN Plus, 53/67 (79% BACTEC Plus and 50/67 (75% BACTEC Lytic bottles. In conclusion, BACTEC Lytic bottles have significantly better detection rates and shorter TTD compared to the three other bottle types. The anaerobic BC bottles are equally suitable for direct MALDI-TOF MS for rapid and reliable identification of common anaerobic bacteria. Further clinical studies are warranted to investigate the performance of anaerobic BC bottles in detection of anaerobic bacteria and identification by direct MALDI-TOF MS.

  16. Effects of Selected Variables on Musicians' Ratings of High-Level Piano Performances

    Science.gov (United States)

    Wapnick, Joel; Ryan, Charlene; Lacaille, Nathalie; Darrow, Alice-Ann

    2004-01-01

    The purpose of this study was to ascertain whether judgments of solo performances recorded at a well-known international piano competition would be affected by musical characteristics such as style (classic period versus early 20th-century Russian) and tempo (slow versus fast). Evaluators rated performances on six test items: tone quality, note…

  17. Multi-GNSS high-rate RTK, PPP and novel direct phase observation processing method: application to precise dynamic displacement detection

    Science.gov (United States)

    Paziewski, Jacek; Sieradzki, Rafal; Baryla, Radoslaw

    2018-03-01

    This paper provides the methodology and performance assessment of multi-GNSS signal processing for the detection of small-scale high-rate dynamic displacements. For this purpose, we used methods of relative (RTK) and absolute positioning (PPP), and a novel direct signal processing approach. The first two methods are recognized as providing accurate information on position in many navigation and surveying applications. The latter is an innovative method for dynamic displacement determination with the use of GNSS phase signal processing. This method is based on the developed functional model with parametrized epoch-wise topocentric relative coordinates derived from filtered GNSS observations. Current regular kinematic PPP positioning, as well as medium/long range RTK, may not offer coordinate estimates with subcentimeter precision. Thus, extended processing strategies of absolute and relative GNSS positioning have been developed and applied for displacement detection. The study also aimed to comparatively analyze the developed methods as well as to analyze the impact of combined GPS and BDS processing and the dependence of the results of the relative methods on the baseline length. All the methods were implemented with in-house developed software allowing for high-rate precise GNSS positioning and signal processing. The phase and pseudorange observations collected with a rate of 50 Hz during the field test served as the experiment’s data set. The displacements at the rover station were triggered in the horizontal plane using a device which was designed and constructed to ensure a periodic motion of GNSS antenna with an amplitude of ~3 cm and a frequency of ~4.5 Hz. Finally, a medium range RTK, PPP, and direct phase observation processing method demonstrated the capability of providing reliable and consistent results with the precision of the determined dynamic displacements at the millimeter level. Specifically, the research shows that the standard deviation of

  18. A longitudinal evaluation of performance of automated BCR-ABL1 quantitation using cartridge-based detection system.

    Science.gov (United States)

    Enjeti, Anoop; Granter, Neil; Ashraf, Asma; Fletcher, Linda; Branford, Susan; Rowlings, Philip; Dooley, Susan

    2015-10-01

    An automated cartridge-based detection system (GeneXpert; Cepheid) is being widely adopted in low throughput laboratories for monitoring BCR-ABL1 transcript in chronic myelogenous leukaemia. This Australian study evaluated the longitudinal performance specific characteristics of the automated system.The automated cartridge-based system was compared prospectively with the manual qRT-PCR-based reference method at SA Pathology, Adelaide, over a period of 2.5 years. A conversion factor determination was followed by four re-validations. Peripheral blood samples (n = 129) with international scale (IS) values within detectable range were selected for assessment. The mean bias, proportion of results within specified fold difference (2-, 3- and 5-fold), the concordance rate of major molecular remission (MMR) and concordance across a range of IS values on paired samples were evaluated.The initial conversion factor for the automated system was determined as 0.43. Except for the second re-validation, where a negative bias of 1.9-fold was detected, all other biases fell within desirable limits. A cartridge-specific conversion factor and efficiency value was introduced and the conversion factor was confirmed to be stable in subsequent re-validation cycles. Concordance with the reference method/laboratory at >0.1-≤10 IS was 78.2% and at ≤0.001 was 80%, compared to 86.8% in the >0.01-≤0.1 IS range. The overall and MMR concordance were 85.7% and 94% respectively, for samples that fell within ± 5-fold of the reference laboratory value over the entire period of study.Conversion factor and performance specific characteristics for the automated system were longitudinally stable in the clinically relevant range, following introduction by the manufacturer of lot specific efficiency values.

  19. Detection of steam generator tube leaks in pressurized water reactors

    International Nuclear Information System (INIS)

    Roach, W.H.

    1984-11-01

    This report addresses the early detection of small steam generator tube leaks in pressurized water reactors. It identifies physical parameters, establishes instrumentation performance goals, and specifies sensor types and locations. It presents a simple algorithm that yields the leak rate as a function of known or measurable quantities. Leak rates of less than one-tenth gram per second should be detectable with existing instrumentation

  20. Detecting nuclear materials smuggling: performance evaluation of container inspection policies.

    Science.gov (United States)

    Gaukler, Gary M; Li, Chenhua; Ding, Yu; Chirayath, Sunil S

    2012-03-01

    In recent years, the United States, along with many other countries, has significantly increased its detection and defense mechanisms against terrorist attacks. A potential attack with a nuclear weapon, using nuclear materials smuggled into the country, has been identified as a particularly grave threat. The system for detecting illicit nuclear materials that is currently in place at U.S. ports of entry relies heavily on passive radiation detectors and a risk-scoring approach using the automated targeting system (ATS). In this article we analyze this existing inspection system and demonstrate its performance for several smuggling scenarios. We provide evidence that the current inspection system is inherently incapable of reliably detecting sophisticated smuggling attempts that use small quantities of well-shielded nuclear material. To counter the weaknesses of the current ATS-based inspection system, we propose two new inspection systems: the hardness control system (HCS) and the hybrid inspection system (HYB). The HCS uses radiography information to classify incoming containers based on their cargo content into "hard" or "soft" containers, which then go through different inspection treatment. The HYB combines the radiography information with the intelligence information from the ATS. We compare and contrast the relative performance of these two new inspection systems with the existing ATS-based system. Our studies indicate that the HCS and HYB policies outperform the ATS-based policy for a wide range of realistic smuggling scenarios. We also examine the impact of changes in adversary behavior on the new inspection systems and find that they effectively preclude strategic gaming behavior of the adversary. © 2011 Society for Risk Analysis.

  1. Using near infrared spectroscopy and heart rate variability to detect mental overload.

    Science.gov (United States)

    Durantin, G; Gagnon, J-F; Tremblay, S; Dehais, F

    2014-02-01

    Mental workload is a key factor influencing the occurrence of human error, especially during piloting and remotely operated vehicle (ROV) operations, where safety depends on the ability of pilots to act appropriately. In particular, excessively high or low mental workload can lead operators to neglect critical information. The objective of the present study is to investigate the potential of functional near infrared spectroscopy (fNIRS) - a non-invasive method of measuring prefrontal cortex activity - in combination with measurements of heart rate variability (HRV), to predict mental workload during a simulated piloting task, with particular regard to task engagement and disengagement. Twelve volunteers performed a computer-based piloting task in which they were asked to follow a dynamic target with their aircraft, a task designed to replicate key cognitive demands associated with real life ROV operating tasks. In order to cover a wide range of mental workload levels, task difficulty was manipulated in terms of processing load and difficulty of control - two critical sources of workload associated with piloting and remotely operating a vehicle. Results show that both fNIRS and HRV are sensitive to different levels of mental workload; notably, lower prefrontal activation as well as a lower LF/HF ratio at the highest level of difficulty, suggest that these measures are suitable for mental overload detection. Moreover, these latter measurements point toward the existence of a quadratic model of mental workload. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Clinical application of S-Detect to breast masses on ultrasonography: A study evaluating the diagnostic performance and agreement with a dedicated breast radiologist

    International Nuclear Information System (INIS)

    Kim, Ki Wook; Kim, Eun Kyung; Yoon, Jung Hyun; Song, Mi Kyung

    2017-01-01

    The purpose of this study was to evaluate the diagnostic performance of S-Detect when applied to breast ultrasonography (US), and the agreement with an experienced radiologist specializing in breast imaging. From June to August 2015, 192 breast masses in 175 women were included. US features of the breast masses were retrospectively analyzed by a radiologist who specializes in breast imaging and S-Detect, according to the fourth edition of the American College of Radiology Breast Imaging Reporting and Data System lexicon and final assessment categories. Final assessments from S-Detect were in dichotomized form: possibly benign and possibly malignant. Kappa statistics were used to analyze the agreement between the radiologist and S-Detect. Diagnostic performance of the radiologist and S-Detect was calculated, including sensitivity, specificity, positive predictive value (PPV), negative predictive value, accuracy, and area under the receiving operator characteristics curve. Of the 192 breast masses, 72 (37.5%) were malignant, and 120 (62.5%) were benign. Benign masses among category 4a had higher rates of possibly benign assessment on S-Detect for the radiologist, 63.5% to 36.5%, respectively (P=0.797). When the cutoff was set at category 4a, the specificity, PPV, and accuracy was significantly higher in S-Detect compared to the radiologist (all P<0.05), with a higher area under the receiver operator characteristics curve of 0.725 compared to 0.653 (P=0.038). Moderate agreement (k=0.58) was seen in the final assessment between the radiologist and S-Detect. S-Detect may be used as an additional diagnostic tool to improve the specificity of breast US in clinical practice, and guide in decision making for breast masses detected on US

  3. Confabulation Based Real-time Anomaly Detection for Wide-area Surveillance Using Heterogeneous High Performance Computing Architecture

    Science.gov (United States)

    2015-06-01

    CONFABULATION BASED REAL-TIME ANOMALY DETECTION FOR WIDE-AREA SURVEILLANCE USING HETEROGENEOUS HIGH PERFORMANCE COMPUTING ARCHITECTURE SYRACUSE...DETECTION FOR WIDE-AREA SURVEILLANCE USING HETEROGENEOUS HIGH PERFORMANCE COMPUTING ARCHITECTURE 5a. CONTRACT NUMBER FA8750-12-1-0251 5b. GRANT...processors including graphic processor units (GPUs) and Intel Xeon Phi processors. Experimental results showed significant speedups, which can enable

  4. A validated high-performance liquid chromatography method with diode array detection for simultaneous determination of nine flavonoids in Senecio cannabifolius Less.

    Science.gov (United States)

    Niu, Tian-Zeng; Zhang, Yu-Wei; Bao, Yong-Li; Wu, Yin; Yu, Chun-Lei; Sun, Lu-Guo; Yi, Jing-Wen; Huang, Yan-Xin; Li, Yu-Xin

    2013-03-25

    A reversed phase high performance liquid chromatography method coupled with a diode array detector (HPLC-DAD) was developed for the first time for the simultaneous determination of 9 flavonoids in Senecio cannabifolius, a traditional Chinese medicinal herb. Agilent Zorbax SB-C18 column was used at room temperature and the mobile phase was a mixture of acetonitrile and 0.5% formic acid (v/v) in water in the gradient elution mode at a flow-rate of 1.0mlmin(-1), detected at 360nm. Validation of this method was performed to verify the linearity, precision, limits of detection and quantification, intra- and inter-day variabilities, reproducibility and recovery. The calibration curves showed good linearities (R(2)>0.9995) within the test ranges. The relative standard deviation (RSD) of the method was less than 3.0% for intra- and inter-day assays. The samples were stable for at least 96h, and the average recoveries were between 90.6% and 102.5%. High sensitivity was demonstrated with detection limits of 0.028-0.085μg/ml for flavonoids. The newly established HPLC method represents a powerful technique for the quality assurance of S. cannabifolius. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Inductively coupled plasma emission spectrometric detection of simulated high performance liquid chromatographic peaks

    International Nuclear Information System (INIS)

    Fraley, D.M.; Yates, D.; Manahan, S.E.

    1979-01-01

    Because of its multielement capability, element-specificity, and low detection limits, inductively coupled plasma optical emission spectrometry (ICP) is a very promising technique for the detection of specific elemental species separated by high performance liquid chromatography (HPLC). This paper evaluated ICP as a detector for HPLC peaks containing specific elements. Detection limits for a number of elements have been evaluated in terms of the minimum detectable concentration of the element at the chromatographic peak maximum. The elements studies were Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Ti, V, and Zn. In addition, ICP was compared with atomic absorption spectrometry for the detection of HPLC peaks composed of EDTA and NTA chelates of copper. Furthermore, ICP was compared to uv solution absorption for the detection of copper chelates. 6 figures, 4 tables

  6. The Effect of Concurrent Music Reading and Performance on the Ability to Detect Tempo Change.

    Science.gov (United States)

    Ellis, Mark Carlton

    1989-01-01

    Measures the ability of three groups of musicians to detect tempo change while reading and performing music. Compares this ability with that of the same musicians to detect tempo change while listening only. Found that for all groups the ability to detect tempo changes was inhibited by the playing task, although to different degrees for each…

  7. Measurement of radiocesium concentration in trees using cumulative gamma radiation dose rate detection systems - A simple presumption for radiocesium concentration in living woods using glass-badge based gamma radiation dose rate detection system

    Energy Technology Data Exchange (ETDEWEB)

    Yoshihara, T.; Hashida, S.N. [Plant Molecular Biology, Laboratory of Environmental Science, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Chiba 270-1194 (Japan); Kawachi, N.; Suzui, N.; Yin, Y.G.; Fujimaki, S. [Radiotracer Imaging Gr., Quantum Beam Science Center, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nagao, Y.; Yamaguchi, M. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-07-01

    Radiocesium from the severe accident at the Fukushima Dai-ichi Nuclear Power Plant on 11 March 2011 contaminates large areas. After this, a doubt for forest products, especially of mushroom, is indelible at the areas. Pruned woody parts and litters are containing a considerable amount of radiocesium, and generates a problem at incineration and composting. These mean that more attentive survey for each subject is expected; however, the present survey system is highly laborious/expensive and/or non-effective for this purpose. On the other hand, we can see a glass-badge based gamma radiation dose rate detection system. This system always utilized to detect a personal cumulative radiation dose, and thus, it is not suitable to separate a radiation from a specific object. However, if we can separate a radiation from a specific object and relate it with the own radiocesium concentration, it would enable us to presume the specific concentration with just an easy monitoring but without a destruction of the target nature and a complicated process including sampling, pre-treatment, and detection. Here, we present the concept of the measurement and results of the trials. First, we set glass-badges (type FS, Chiyoda Technol Corp., Japan) on a part of bough (approximately 10 cm in diameter) of Japanese flowering cherry trees (Prunus x yedoensis cv. Somei-Yoshino) with four different settings: A, a direct setting without any shield; B, a setting with an aluminum shield between bough and the glass-badge; C, a setting with a lead shield between bough and the glass-badge; D, a setting with a lead shield covering the glass-badge to shut the radiation from the surrounding but from bough. The deduction between the amount of each setting should separate a specific radiation of the bough from unlimited radiation from the surrounding. Even if the hourly dose rate is not enough to count the difference, a moderate cumulative dose would clear the difference. In fact, results demonstrated a

  8. The use of high definition colonoscopy versus standard definition: does it affect polyp detection rate?

    Science.gov (United States)

    Richardson, John; Thaventhiran, Anthony; Mackenzie, Hugh; Stubbs, Benjamin

    2017-11-03

    Polyp detection rate (PDR) during lower gastrointestinal endoscopy (LGIE) is of clinical importance. Detecting adenomatous polyps early in the adenoma-carcinoma sequence can halt disease progression, enabling treatment at a favourable stage. High definition colonoscopy (HDC) has been used in our hospital alongside standard definition equipment since 2011. We aim to determine what affect the use of HDC has on PDR. Post-hoc analysis of a prospectively maintained database on all patients undergoing LGIE was performed (01/01/2012-31/12/2015), n = 15,448. Analysis tested the primary outcome of HD's effect on PDR across LGIE and secondary outcome stratified this by endoscopist group (Physician (PE), Surgeon (SE) and Nurse Endoscopist (NE)). Of 15,448 patients, 1353 underwent HDC. Unmatched analysis showed PDR increased by 5.3% in this group (p < 0.001). Matched analysis considered 2288 patients from the total cohort (1144 HDC) and showed an increase of 1% in PDR with HDC (p = 0.578). Further unmatched analysis stratified by endoscopist groups showed a PDR increase of 1.8% (p = 0.375), 5.4% (p = 0.008) and 4.6% (p = 0.021) by PE, SE and NE respectively. Matched analysis demonstrated an increase of 1% (p = 0.734) and 1.5% (p = 0.701) amongst PE and NE, with a decrease of 0.6% (p = 0.883) by SE. The introduction of HDC increased PDR across all LGIE in our hospital, though this was not clinically significant. This marginal benefit was present across all endoscopist groups with no group benefiting over another in matched analysis.

  9. Participation rate or informed choice? Rethinking the European key performance indicators for mammography screening.

    Science.gov (United States)

    Strech, Daniel

    2014-03-01

    Despite the intensive controversies about the likelihood of benefits and harms of mammography screening almost all experts conclude that the choice to screen or not to screen needs to be made by the individual patient who is adequately informed. However, the "European guideline for quality assurance in breast cancer screening and diagnosis" specifies a participation rate of 70% as the key performance indicator for mammography screening. This paper argues that neither the existing evidence on benefits and harms, nor survey research with women, nor compliance rates in clinical trials, nor cost-effectiveness ratios justify participation rates as a reasonable performance indicator for preference-sensitive condition such as mammography screening. In contrast, an informed choice rate would be more reasonable. Further research needs to address the practical challenges in assessing informed choice rates. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Acoustic detection in superconducting magnets for performance characterization and diagnostics

    OpenAIRE

    Marchevsky, M.; Wang, X.; Sabbi, G.; Prestemon, S.

    2014-01-01

    Quench diagnostics in superconducting accelerator magnets is essential for understanding performance limitations and improving magnet design. Applicability of the conventional quench diagnostics methods such as voltage taps or quench antennas is limited for long magnets or complex winding geometries, and alternative approaches are desirable. Here, we discuss acoustic sensing technique for detecting mechanical vibrations in superconducting magnets. Using LARP high-field Nb3Sn quadrupole HQ01 [...

  11. THE DETECTION RATE OF EARLY UV EMISSION FROM SUPERNOVAE: A DEDICATED GALEX/PTF SURVEY AND CALIBRATED THEORETICAL ESTIMATES

    Energy Technology Data Exchange (ETDEWEB)

    Ganot, Noam; Gal-Yam, Avishay; Ofek, Eran O.; Sagiv, Ilan; Waxman, Eli; Lapid, Ofer [Department of Particle Physics and Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Kulkarni, Shrinivas R.; Kasliwal, Mansi M. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Ben-Ami, Sagi [Smithsonian Astrophysical Observatory, Harvard-Smithsonian Ctr. for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chelouche, Doron; Rafter, Stephen [Physics Department, Faculty of Natural Sciences, University of Haifa, 31905 Haifa (Israel); Behar, Ehud; Laor, Ari [Physics Department, Technion Israel Institute of Technology, 32000 Haifa (Israel); Poznanski, Dovi; Nakar, Ehud; Maoz, Dan [School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel); Trakhtenbrot, Benny [Institute for Astronomy, ETH Zurich, Wolfgang-Pauli-Strasse 27 Zurich 8093 (Switzerland); Neill, James D.; Barlow, Thomas A.; Martin, Christofer D., E-mail: noam.ganot@gmail.com [California Institute of Technology, 1200 East California Boulevard, MC 278-17, Pasadena, CA 91125 (United States); Collaboration: ULTRASAT Science Team; WTTH consortium; GALEX Science Team; Palomar Transient Factory; and others

    2016-03-20

    The radius and surface composition of an exploding massive star, as well as the explosion energy per unit mass, can be measured using early UV observations of core-collapse supernovae (SNe). We present the first results from a simultaneous GALEX/PTF search for early ultraviolet (UV) emission from SNe. Six SNe II and one Type II superluminous SN (SLSN-II) are clearly detected in the GALEX near-UV (NUV) data. We compare our detection rate with theoretical estimates based on early, shock-cooling UV light curves calculated from models that fit existing Swift and GALEX observations well, combined with volumetric SN rates. We find that our observations are in good agreement with calculated rates assuming that red supergiants (RSGs) explode with fiducial radii of 500 R{sub ⊙}, explosion energies of 10{sup 51} erg, and ejecta masses of 10 M{sub ⊙}. Exploding blue supergiants and Wolf–Rayet stars are poorly constrained. We describe how such observations can be used to derive the progenitor radius, surface composition, and explosion energy per unit mass of such SN events, and we demonstrate why UV observations are critical for such measurements. We use the fiducial RSG parameters to estimate the detection rate of SNe during the shock-cooling phase (<1 day after explosion) for several ground-based surveys (PTF, ZTF, and LSST). We show that the proposed wide-field UV explorer ULTRASAT mission is expected to find >85 SNe per year (∼0.5 SN per deg{sup 2}), independent of host galaxy extinction, down to an NUV detection limit of 21.5 mag AB. Our pilot GALEX/PTF project thus convincingly demonstrates that a dedicated, systematic SN survey at the NUV band is a compelling method to study how massive stars end their life.

  12. FahamecV1:A Low Cost Automated Metaphase Detection System

    Directory of Open Access Journals (Sweden)

    H. Yilmaz

    2017-12-01

    Full Text Available In this study, FahamecV1 is introduced and investigated as a low cost and high accuracy solution for metaphase detection. Chromosome analysis is performed at the metaphase stage and high accuracy and automated detection of the metaphase stage plays an active role in decreasing analysis time. FahamecV1 includes an optic microscope, a motorized microscope stage, an electronic control unit, a camera, a computer and a software application. Printing components of the motorized microscope stage (using a 3D printer is of the main reasons for cost reduction. Operations such as stepper motor calibration, are detection, focusing, scanning, metaphase detection and saving of coordinates into a database are automatically performed. To detect metaphases, a filter named Metafilter is developed and applied. Average scanning time per preparate is 77 sec/cm2. True positive rate is calculated as 95.1%, true negative rate is calculated as 99.0% and accuracy is calculated as 98.8%.

  13. Reaction rate constant of HO2+O3 measured by detecting HO2 from photofragment fluorescence

    Science.gov (United States)

    Manzanares, E. R.; Suto, Masako; Lee, Long C.; Coffey, Dewitt, Jr.

    1986-01-01

    A room-temperature discharge-flow system investigation of the rate constant for the reaction 'HO2 + O3 yields OH + 2O2' has detected HO2 through the OH(A-X) fluorescence produced by photodissociative excitation of HO2 at 147 nm. A reaction rate constant of 1.9 + or - 0.3 x 10 to the -15th cu cm/molecule per sec is obtained from first-order decay of HO2 in excess O3; this agrees well with published data.

  14. Trained neurons-based motion detection in optical camera communications

    Science.gov (United States)

    Teli, Shivani; Cahyadi, Willy Anugrah; Chung, Yeon Ho

    2018-04-01

    A concept of trained neurons-based motion detection (TNMD) in optical camera communications (OCC) is proposed. The proposed TNMD is based on neurons present in a neural network that perform repetitive analysis in order to provide efficient and reliable motion detection in OCC. This efficient motion detection can be considered another functionality of OCC in addition to two traditional functionalities of illumination and communication. To verify the proposed TNMD, the experiments were conducted in an indoor static downlink OCC, where a mobile phone front camera is employed as the receiver and an 8 × 8 red, green, and blue (RGB) light-emitting diode array as the transmitter. The motion is detected by observing the user's finger movement in the form of centroid through the OCC link via a camera. Unlike conventional trained neurons approaches, the proposed TNMD is trained not with motion itself but with centroid data samples, thus providing more accurate detection and far less complex detection algorithm. The experiment results demonstrate that the TNMD can detect all considered motions accurately with acceptable bit error rate (BER) performances at a transmission distance of up to 175 cm. In addition, while the TNMD is performed, a maximum data rate of 3.759 kbps over the OCC link is obtained. The OCC with the proposed TNMD combined can be considered an efficient indoor OCC system that provides illumination, communication, and motion detection in a convenient smart home environment.

  15. On the performance of data receivers with a restricted detection delay

    NARCIS (Netherlands)

    Bergmans, J.W.M.; Willems, F.M.J.; Kerpen, G.S.M.

    1994-01-01

    It is well known that the performance of a data receiver for an intersymbol interference (ISI) channel can depend strongly on the detection delay d. For a discrete-time communication system, this paper derives a lower bound on the bit-error probability as a function of d. This "restricted delay

  16. Reproductive performance of gilts according to growth rate and backfat thickness at mating.

    Science.gov (United States)

    Amaral Filha, W S; Bernardi, M L; Wentz, I; Bortolozzo, F P

    2010-08-01

    The study evaluated the influence of growth rate (GR) and backfat thickness (BF), at first mating of gilts, on the reproductive performance until the first farrowing and on the variation in birth weight of piglets. Gilts were categorized into three groups according to GR from birth until the first mating: GRI (600-700 g/d; n = 345), GRII (701-770 g/d; n = 710) and GRIII (771-870 g/d; n = 366). Analyses were also performed considering three groups formed according to BF (mm) at mating: BFI (10-15 mm; n = 405); BFII (16-17 mm; n = 649)and BFIII (18-23 mm; n = 367). There were no differences in farrowing rate and return to estrus rate among BF or GR groups (P > 0.05). GRII and GRIII females had larger litter size compared to GRI gilts (P GRI and GRII females. Moreover GRIII females had more piglets (P GRI females. More total born and born alive piglets were observed in BFII compared with BFI females (P 0.05). These results show that there is no advantage, in terms of farrowing rate and number of born alive, in performing the first mating of gilts with GR> 770 g/d and BF > 17 mm.

  17. Assessing the detectability of antioxidants in two-dimensional high-performance liquid chromatography.

    Science.gov (United States)

    Bassanese, Danielle N; Conlan, Xavier A; Barnett, Neil W; Stevenson, Paul G

    2015-05-01

    This paper explores the analytical figures of merit of two-dimensional high-performance liquid chromatography for the separation of antioxidant standards. The cumulative two-dimensional high-performance liquid chromatography peak area was calculated for 11 antioxidants by two different methods--the areas reported by the control software and by fitting the data with a Gaussian model; these methods were evaluated for precision and sensitivity. Both methods demonstrated excellent precision in regards to retention time in the second dimension (%RSD below 1.16%) and cumulative second dimension peak area (%RSD below 3.73% from the instrument software and 5.87% for the Gaussian method). Combining areas reported by the high-performance liquid chromatographic control software displayed superior limits of detection, in the order of 1 × 10(-6) M, almost an order of magnitude lower than the Gaussian method for some analytes. The introduction of the countergradient eliminated the strong solvent mismatch between dimensions, leading to a much improved peak shape and better detection limits for quantification. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Surface detection performance evaluation of pseudo-random noise continuous wave laser radar

    Science.gov (United States)

    Mitev, Valentin; Matthey, Renaud; Pereira do Carmo, Joao

    2017-11-01

    A number of space missions (including in the ESA Exploration Programme) foreseen a use of laser radar sensor (or lidar) for determination of range between spacecrafts or between spacecraft and ground surface (altimetry). Such sensors need to be compact, robust and power efficient, at the same time with high detection performance. These requirements can be achieved with a Pseudo-Random Noise continuous wave lidar (PRN cw lidar). Previous studies have pointed to the advantages of this lidar with respect to space missions, but they also identified its limitations in high optical background. The progress of the lasers and the detectors in the near IR spectral range requires a re-evaluation of the PRN cw lidar potential. Here we address the performances of this lidar for surface detection (altimetry) in planetary missions. The evaluation is based on the following system configuration: (i) A cw fiber amplifier as lidar transmitter. The seeding laser exhibits a single-frequency spectral line, with subsequent amplitude modulation. The fiber amplifier allows high output power level, keeping the spectral characteristics and the modulation of the seeding light input. (ii) An avalanche photodiode in photon counting detection; (iii) Measurement scenarios representative for Earth, Mercury and Mars.

  19. Nodule detection methods using autocorrelation features on 3D chest CT scans

    International Nuclear Information System (INIS)

    Hara, T.; Zhou, X.; Okura, S.; Fujita, H.; Kiryu, T.; Hoshi, H.

    2007-01-01

    Lung cancer screening using low dose X-ray CT scan has been an acceptable examination to detect cancers at early stage. We have been developing an automated detection scheme for lung nodules on CT scan by using second-order autocorrelation features and the initial performance for small nodules (< 10 mm) shows a high true-positive rate with less than four false-positive marks per case. In this study, an open database of lung images, LIDC (Lung Image Database Consortium), was employed to evaluate our detection scheme as an consistency test. The detection performance for solid and solitary nodules in LIDC, included in the first data set opened by the consortium, was 83% (10/12) true-positive rate with 3.3 false-positive marks per case. (orig.)

  20. No influence of smoking status on the performance of urine markers for the detection of bladder cancer.

    Science.gov (United States)

    Deininger, Susanne; Hennenlotter, J; Rausch, S; Docktor, K; Neumann, E; da Costa, I A; Bedke, J; Stenzl, A; Todenhöfer, T

    2018-04-19

    The performance of urinary markers for detecting bladder cancer (BC) is influenced by various factors. The aim of the present study was to evaluate the influence of smoking habits on the performance of four commonly used urine markers. Urine samples of 723 patients with suspected BC were analysed using urine cytology, fluorescence in situ hybridization (FISH), immunocytology (uCyt+ test), and quantitative nuclear matrix protein 22 (NMP22) immunoassay. The smoking habits of all patients were recorded and a cystoscopy performed within 2 weeks after urinary marker testing. Rates of false negative and false positive results were compared between non-smokers, former smokers, and current smokers by contingency analyses. We included 723 patients in this study, 431 (59.6%) of which were non-smokers, 215 former smokers (29.7%), and 77 (10.7%) current smokers. 148 patients (20.5%) had a tumour at the time of urinary marker testing. Respective rates of false positive test results among non-smokers, former smokers, and current smokers were: 16.3, 19.1, and 11.5% (p = 0.81) for urine cytology; 36.8, 42.0, and 32.7% for the uCyt+ test (p = 0.88); 18.0, 19.1, and 13.5% for FISH (p = 0.66); and 69.5, 71.6, and 71.2% for NMP22 (p = 0.67). Respective rates of false negatives among non-smokers, former smokers, and current smokers were: 31.4, 15.1, and 28.0% for cytology (p = 0.34); 21.4, 22.6, and 16.0% for uCyt+ test (p = 0.67); 24.3, 13.2, and 28.0% for FISH (p = 0.88); and 10.0, 18.9, and 8.0% for NMP22 (p = 0.80). Our results strongly suggest that smoking habits do not affect performance characteristics of urinary markers in the diagnostics of BC.

  1. Design and Performance Investigation for the Optical Combinational Networks at High Data Rate

    Science.gov (United States)

    Tripathi, Devendra Kr.

    2017-05-01

    This article explores performance study for optical combinational designs based on nonlinear characteristics with semiconductor optical amplifier (SOA). Two configurations for optical half-adder with non-return-to-zero modulation pattern altogether with Mach-Zehnder modulator, interferometer at 50-Gbps data rate have been successfully realized. Accordingly, SUM and CARRY outputs have been concurrently executed and verified for their output waveforms. Numerical simulations for variation of data rate and key design parameters have been effectively executed outcome with optimum performance. Investigations depict overall good performance of the design in terms of the extinction factor. It also inferred that all-optical realization based on SOA is competent scheme, as it circumvents costly optoelectronic translation. This could be well supportive to erect larger complex optical combinational circuits.

  2. Performance of slow rate systems for treatment of domestic wastewater.

    Science.gov (United States)

    Tzanakakis, V E; Paranychianakis, N V; Angelakis, A N

    2007-01-01

    The performance of slow rate (SR) systems in terms of treatment efficiency, environmental and health risks, and land sustainability was investigated over a three-year period in a rural community close to Iraklio, Greece. Four plant species (Acacia cyanophylla, Eucalyptus camandulensis, Populus nigra and Arundo donax) were used in order to investigate the role of vegetation in the treatment of wastewater and in biomass production. Wastewater effluent was pre-treated in a septic tank before its application to land. Applied hydraulic loading rates were based on crop water requirements which were determined separately for each plant species. The evaluation of treatment performance was accomplished by measuring COD, TKN, NH3-N, NO3-N, total and reactive P, TC and FC in soil solution samples taken at different depths (15, 30 and 60 cm). SR systems showed great potential for COD, TKN and NH4-N removal which reached 89, 90 and 94%, respectively at a depth of 15 cm. An outstanding removal was also observed for TC and FC which reached 99.99%. The concentration of both P and NO3-N in soil solution increased with the passage of time, but it was lower in winter. Despite the differences in the application rates among the SR systems planted with different plant species, the treatment efficiency was not affected. Moreover, increasing the soil depth from 15 to 60 cm had no effect on the treatment efficiency of the SR systems.

  3. The Effect of Selected Nonmusical Factors on Adjudicators' Ratings of High School Solo Vocal Performances

    Science.gov (United States)

    Howard, Sandra A.

    2012-01-01

    The purpose of this study was to examine the effect of differentiated performance attire and stage deportment on adjudicators' ratings of high school solo vocal performances. High school choral students (n = 153) and undergraduate (n = 97) and graduate music majors (n = 32) served as adjudicators (N = 282). Adjudicators rated recorded solo vocal…

  4. High Rate Performance Nanocomposite Electrode of Mesoporous Manganese Dioxide/Silver Nanowires in KI Electrolytes

    Directory of Open Access Journals (Sweden)

    Yanhua Jiang

    2015-10-01

    Full Text Available In recent years, manganese dioxide has become a research hotspot as an electrode material because of its low price. However, it has also become an obstacle to industrialization due to its low ratio of capacitance and the low rate performance which is caused by the poor electrical conductivity. In this study, a KI solution with electrochemical activity was innovatively applied to the electrolyte, and we systematically investigated the rate performance of the mesoporous manganese dioxide and the composite electrode with silver nanowires in supercapacitors. The results showed that when mesoporous manganese dioxide and mesoporous manganese dioxide/silver nanowires composite were used as electrodes, the strength of the current was amplified five times (from 0.1 to 0.5 A/g, the remaining rates of specific capacitance were 95% (from 205.5 down to 197.1 F/g and 92% (from 208.1 down to 191.7 F/g in the KI electrolyte, and the rate performance was much higher than which in an Na2SO4 electrolyte with a remaining rate of 25% (from 200.3 down to 49.1 F/g and 60% (from 187.2 down to 113.1 F/g. The morphology and detail structure were investigated by Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry and Nitrogen adsorption-desorption isotherms. The electrochemical performance was assessed by cyclic voltammograms, galvanostatic charge/discharge and electrochemical impedance spectroscopy.

  5. Channel selection for automatic seizure detection

    DEFF Research Database (Denmark)

    Duun-Henriksen, Jonas; Kjaer, Troels Wesenberg; Madsen, Rasmus Elsborg

    2012-01-01

    Objective: To investigate the performance of epileptic seizure detection using only a few of the recorded EEG channels and the ability of software to select these channels compared with a neurophysiologist. Methods: Fifty-nine seizures and 1419 h of interictal EEG are used for training and testing...... of an automatic channel selection method. The characteristics of the seizures are extracted by the use of a wavelet analysis and classified by a support vector machine. The best channel selection method is based upon maximum variance during the seizure. Results: Using only three channels, a seizure detection...... sensitivity of 96% and a false detection rate of 0.14/h were obtained. This corresponds to the performance obtained when channels are selected through visual inspection by a clinical neurophysiologist, and constitutes a 4% improvement in sensitivity compared to seizure detection using channels recorded...

  6. Sleep-spindle detection: crowdsourcing and evaluating performance of experts, non-experts and automated methods

    DEFF Research Database (Denmark)

    Warby, Simon C.; Wendt, Sabrina Lyngbye; Welinder, Peter

    2014-01-01

    to crowdsource spindle identification by human experts and non-experts, and we compared their performance with that of automated detection algorithms in data from middle- to older-aged subjects from the general population. We also refined methods for forming group consensus and evaluating the performance...... of event detectors in physiological data such as electroencephalographic recordings from polysomnography. Compared to the expert group consensus gold standard, the highest performance was by individual experts and the non-expert group consensus, followed by automated spindle detectors. This analysis showed...... that crowdsourcing the scoring of sleep data is an efficient method to collect large data sets, even for difficult tasks such as spindle identification. Further refinements to spindle detection algorithms are needed for middle- to older-aged subjects....

  7. Colour Doppler and microbubble contrast agent ultrasonography do not improve cancer detection rate in transrectal systematic prostate biopsy sampling.

    Science.gov (United States)

    Taverna, Gianluigi; Morandi, Giovanni; Seveso, Mauro; Giusti, Guido; Benetti, Alessio; Colombo, Piergiuseppe; Minuti, Francesco; Grizzi, Fabio; Graziotti, Pierpaolo

    2011-12-01

    What's known on the subject? and What does the study add? Transrectal gray-scale ultrasonography guided prostate biopsy sampling is the method for diagnosing prostate cancer (PC) in patients with an increased prostate specific antigen level and/or abnormal digital rectal examination. Several imaging strategies have been proposed to optimize the diagnostic value of biopsy sampling, although at the first biopsy nearly 10-30% of PC still remains undiagnosed. This study compares the PC detection rate when employing Colour Doppler ultransongraphy with or without the injection of SonoVue™ microbubble contrast agent, versus the transrectal ultrasongraphy-guided systematic biopsy sampling. The limited accuracy, sensitivity, specificity and the additional cost of using the contrast agent do not justify its routine application in PC detection. • To compare prostate cancer (PC) detection rate employing colour Doppler ultrasonography with or without SonoVue™ contrast agent with transrectal ultrasonography-guided systematic biopsy sampling. • A total of 300 patients with negative digital rectal examination and transrectal grey-scale ultrasonography, with PSA values ranging between 2.5 and 9.9 ng/mL, were randomized into three groups: 100 patients (group A) underwent transrectal ultrasonography-guided systematic bioptic sampling; 100 patients (group B) underwent colour Doppler ultrasonography, and 100 patients (group C) underwent colour Doppler ultrasonography before and during the injection of SonoVue™. • Contrast-enhanced targeted biopsies were sampled into hypervascularized areas of peripheral, transitional, apical or anterior prostate zones. • All the patients included in Groups B and C underwent a further 13 systematic prostate biopsies. The cancer detection rate was calculated for each group. • In 88 (29.3%) patients a histological diagnosis of PC was made, whereas 22 (7.4%) patients were diagnosed with high-grade prostatic intraepithelial

  8. Beating the random walk: a performance assessment of long-term interest rate forecasts

    NARCIS (Netherlands)

    den Butter, F.A.G.; Jansen, P.W.

    2013-01-01

    This article assesses the performance of a number of long-term interest rate forecast approaches, namely time series models, structural economic models, expert forecasts and combinations thereof. The predictive performance of these approaches is compared using outside sample forecast errors, where a

  9. Performance evaluation of sea surface simulation methods for target detection

    Science.gov (United States)

    Xia, Renjie; Wu, Xin; Yang, Chen; Han, Yiping; Zhang, Jianqi

    2017-11-01

    With the fast development of sea surface target detection by optoelectronic sensors, machine learning has been adopted to improve the detection performance. Many features can be learned from training images by machines automatically. However, field images of sea surface target are not sufficient as training data. 3D scene simulation is a promising method to address this problem. For ocean scene simulation, sea surface height field generation is the key point to achieve high fidelity. In this paper, two spectra-based height field generation methods are evaluated. Comparison between the linear superposition and linear filter method is made quantitatively with a statistical model. 3D ocean scene simulating results show the different features between the methods, which can give reference for synthesizing sea surface target images with different ocean conditions.

  10. Recovery Efficiency, False Negative Rate, and Limit of Detection Performance of a Validated Macrofoam-Swab Sampling Method with Low Surface Concentrations of Two Bacillus anthracis Surrogates

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaiser, Brooke L. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sydor, Michael A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Barrett, Christopher A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-06-16

    The performance of a macrofoam-swab sampling method was evaluated using Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus Nakamura (BG) spores applied at nine low target amounts (2-500 spores) to positive-control plates and test coupons (2 in × 2 in) of four surface materials (glass, stainless steel, vinyl tile, and plastic). Test results from cultured samples were used to evaluate the effects of surrogate, surface concentration, and surface material on recovery efficiency (RE), false negative rate (FNR), and limit of detection. For RE, surrogate and surface material had statistically significant effects, but concentration did not. Mean REs were the lowest for vinyl tile (50.8% with BAS, 40.2% with BG) and the highest for glass (92.8% with BAS, 71.4% with BG). FNR values ranged from 0 to 0.833 for BAS and 0 to 0.806 for BG, with values increasing as concentration decreased in the range tested (0.078 to 19.375 CFU/cm2, where CFU denotes ‘colony forming units’). Surface material also had a statistically significant effect. A FNR-concentration curve was fit for each combination of surrogate and surface material. For both surrogates, the FNR curves tended to be the lowest for glass and highest for vinyl title. The FNR curves for BG tended to be higher than for BAS at lower concentrations, especially for glass. Results using a modified Rapid Viability-Polymerase Chain Reaction (mRV-PCR) analysis method were also obtained. The mRV-PCR results and comparisons to the culture results are discussed in a separate report.

  11. Recovery Efficiency, False Negative Rate, and Limit of Detection Performance of a Validated Macrofoam-Swab Sampling Method with Low Surface Concentrations of Two Bacillus anthracis Surrogates

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deatherage Kaiser, Brooke L [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sydor, Michael A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Barrett, Christopher A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-31

    The performance of a macrofoam-swab sampling method was evaluated using Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus Nakamura (BG) spores applied at nine low target amounts (2-500 spores) to positive-control plates and test coupons (2 in. × 2 in.) of four surface materials (glass, stainless steel, vinyl tile, and plastic). Test results from cultured samples were used to evaluate the effects of surrogate, surface concentration, and surface material on recovery efficiency (RE), false negative rate (FNR), and limit of detection. For RE, surrogate and surface material had statistically significant effects, but concentration did not. Mean REs were the lowest for vinyl tile (50.8% with BAS, 40.2% with BG) and the highest for glass (92.8% with BAS, 71.4% with BG). FNR values ranged from 0 to 0.833 for BAS and 0 to 0.806 for BG, with values increasing as concentration decreased in the range tested (0.078 to 19.375 CFU/cm2, where CFU denotes ‘colony forming units’). Surface material also had a statistically significant effect. A FNR-concentration curve was fit for each combination of surrogate and surface material. For both surrogates, the FNR curves tended to be the lowest for glass and highest for vinyl title. The FNR curves for BG tended to be higher than for BAS at lower concentrations, especially for glass. Results using a modified Rapid Viability-Polymerase Chain Reaction (mRV-PCR) analysis method were also obtained. The mRV-PCR results and comparisons to the culture results will be discussed in a subsequent report.

  12. Effect of Resident Performance on Midurethral Sling Cure and Complication Rates

    Directory of Open Access Journals (Sweden)

    Sabri Cavkaytar

    2016-01-01

    Full Text Available Aim: To evaluate the cure rates and complications of midurethral slings performed by residents under an experienced surgeon supervision. Material and Method: Between January 2013 and January 2014, one hundred forty-one midurethral slings performed in the urogynecology clinic of Ankara Zekai Tahir Burak Women%u2019s Health Research and Education Hospital were reviewed.Age, parity,body mass index,menopausal status, grade 2 preoperative pelvic organ prolapsus,concomitant vaginal surgery and intraoperative (bladder and bowel perforations,bleeding,vaginal laceration and early postoperative (urinary retention etc.complications were recorded.All women were re-examined at postoperative 6 th month and symptoms were questioned. The patients were classified as %u2018%u2019cured%u2019%u2019 if the stress test was negative , %u2018%u2019partially cured%u2019%u2019 if continence frequency decreased but still continued and %u2018%u2019unsatisfied%u2019%u2019 if there was no change in symptoms. Both TVT and TOT groups were compared in case of complications and cure rates. Results: Among 141 patients who had undergone midurethral sling due to urinary stress incontinence,50(35.5% were TOT , 91(64.5% were TVT. In the TVT group, 3 (3.3% patients had bleeding which requires transfusion and 5(5.5% patients had bladder perforations. But in the TOT group,there was no bladder perforation and bleeding that requires transfusion. In the early postoperative period, urinary retention was encountered in 7(14.0% patients in TOT group and in 17(18.7% patients in TVT group. There was no statistically significant difference between the groups in case of complications. At postoperative 6th month, in the TOT group 76% of patients were cured,18% were partially cured and 6% were unsatisfied. In the TVT group, 83.5% of patients were cured, 12.1% were partially cured and 4.4% were unsatisfied and there was no significant difference in cure rates between the groups. Discussion: The

  13. Impact of changing from staining to culture techniques on detection rates of Campylobacter spp. in routine stool samples in Chile.

    Science.gov (United States)

    Porte, Lorena; Varela, Carmen; Haecker, Thomas; Morales, Sara; Weitzel, Thomas

    2016-05-13

    Campylobacter is a leading cause of bacterial gastroenteritis, but sensitive diagnostic methods such as culture are expensive and often not available in resource limited settings. Therefore, direct staining techniques have been developed as a practical and economical alternative. We analyzed the impact of replacing Campylobacter staining with culture for routine stool examinations in a private hospital in Chile. From January to April 2014, a total of 750 consecutive stool samples were examined in parallel by Hucker stain and Campylobacter culture. Isolation rates of Campylobacter were determined and the performance of staining was evaluated against culture as the gold standard. Besides, isolation rates of Campylobacter and other enteric pathogens were compared to those of past years. Campylobacter was isolated by culture in 46 of 750 (6.1 %) stool samples. Direct staining only identified three samples as Campylobacter positive and reached sensitivity and specificity values of 6.5 and 100 %, respectively. In comparison to staining-based detection rates of previous years, we observed a significant increase of Campylobacter cases in our patients. Direct staining technique for Campylobacter had a very low sensitivity compared to culture. Staining methods might lead to a high rate of false negative results and an underestimation of the importance of campylobacteriosis. With the inclusion of Campylobacter culture, this pathogen became a leading cause of intestinal infection in our patient population.

  14. Scintillating-Glass-Fiber neutron sensors, their application and performance for plutonium detection and monitoring

    International Nuclear Information System (INIS)

    Seymour, R.S.; Richardson, B.; Morichi, M.; Bliss, M.; Craig, R.A.; Sunberg, D.S.

    1998-01-01

    Most neutron detection sensors presently employ 3 He gas-filled detectors. Despite their excellent performance and widespread use, there are significant limitations to this technology. A significant alternative neutron sensor utilizing neutron-active material incorporated into a glass scintillator is presented that offers novel commercial sensors not possible or practical with gas tube technology. The scintillating optical fiber permits sensors with a multitude of sizes ranging from devices of a single fiber of 150μm to sensors with tens of thousands of fibers with areas as large as 5m 2 depending on the neutron flux to be measured. A second significant advantage is the use of high-speed electronics that allow a greater dynamic range, not possible with gas detectors. These sensors are flexible, conformable and less sensitive to vibration that optimizes the source-to-detector geometry and provides robust performance in field applications. The glass-fibers are sensitive to both gamma rays and neutrons. However the coincidence electronics are optimized for neutron to gamma ray discrimination allowing very sensitive measurements with a low false-alarm rate. Applications include SNM surveillance, material control and accountability (MC and A), safeguard inspections, Pu health physics / bioassay and environmental characterization. (author)

  15. Comparative analysis of methods for detecting interacting loci.

    Science.gov (United States)

    Chen, Li; Yu, Guoqiang; Langefeld, Carl D; Miller, David J; Guy, Richard T; Raghuram, Jayaram; Yuan, Xiguo; Herrington, David M; Wang, Yue

    2011-07-05

    Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs), with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR), full interaction model (FIM), information gain (IG), Bayesian epistasis association mapping (BEAM), SNP harvester (SH), maximum entropy conditional probability modeling (MECPM), logistic regression with an interaction term (LRIT), and logistic regression (LR) were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the methods to control the type I error rate

  16. Comparative analysis of methods for detecting interacting loci

    Directory of Open Access Journals (Sweden)

    Yuan Xiguo

    2011-07-01

    Full Text Available Abstract Background Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. Results We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs, with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR, full interaction model (FIM, information gain (IG, Bayesian epistasis association mapping (BEAM, SNP harvester (SH, maximum entropy conditional probability modeling (MECPM, logistic regression with an interaction term (LRIT, and logistic regression (LR were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the

  17. Performance evaluation of PFBR wire type sodium leak detectors

    International Nuclear Information System (INIS)

    Vijayakumar, G.; Rajan, K.K.; Nashine, B.K.; Chandramouli, S.; Madhusoodanan, K.; Kalyanasundaram, P.

    2011-01-01

    Highlights: → Performance evaluation of wire type leak detectors was conducted in LEENA facility by creating sodium leaks. → The lowest leak rate of 214 g/h was detected in 50 min and the highest detection time was 6 h for a leak rate of 222 g/h. → Factors affecting the leak detection time are packing density of thermal insulation, layout of heater, temperature, etc. → Relationship between leak rate and detection time was established and a leak rate of 100 g/h is likely to be detected in 11.1 h. → Contact resistance of leaked sodium increased to 3.5 kilo ohms in 20 h. - Abstract: Wire type leak detectors working on conductivity principle are used for detecting sodium leak in the secondary sodium circuits of fast breeder reactors. It is required to assess the performance of these detectors and confirm that they are meeting the requirements. A test facility by name LEENA was constructed at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam to test the wire type leak detector lay out by simulating different sodium leak rates. This test facility consists of a sodium dump tank, a test vessel, interconnecting pipelines with valves, micro filter and test section with leak simulators. There are three different test sections in the test set up of length 1000 mm each. These test sections simulate piping of Prototype Fast Breeder Reactor (PFBR) secondary circuit and the wire type leak detector layout in full scale. All test sections are provided with leak simulators. A leak simulator consists of a hole of size one mm drilled in the test section and closed with a tapered pin. The tapered pin position in the hole is adjusted by a screw mechanism and there by the annular gap of flow area is varied for getting different leak rates. Various experiments were conducted to evaluate the performance of the leak detectors by creating different sodium leak rates. This paper deals with the details of wire type leak detector layout for the secondary sodium circuit of

  18. Variable terrestrial GPS telemetry detection rates: Addressing the probability of successful acquisitions

    Science.gov (United States)

    Ironside, Kirsten E.; Mattson, David J.; Choate, David; Stoner, David; Arundel, Terry; Hansen, Jered R.; Theimer, Tad; Holton, Brandon; Jansen, Brian; Sexton, Joseph O.; Longshore, Kathleen M.; Edwards, Thomas C.; Peters, Michael

    2017-01-01

    Studies using global positioning system (GPS) telemetry rarely result in 100% fix success rates (FSR), which may bias datasets because data loss is systematic rather than a random process. Previous spatially explicit models developed to correct for sampling bias have been limited to small study areas, a small range of data loss, or were study-area specific. We modeled environmental effects on FSR from desert to alpine biomes, investigated the full range of potential data loss (0–100% FSR), and evaluated whether animal body position can contribute to lower FSR because of changes in antenna orientation based on GPS detection rates for 4 focal species: cougars (Puma concolor), desert bighorn sheep (Ovis canadensis nelsoni), Rocky Mountain elk (Cervus elaphus nelsoni), and mule deer (Odocoileus hemionus). Terrain exposure and height of over story vegetation were the most influential factors affecting FSR. Model evaluation showed a strong correlation (0.88) between observed and predicted FSR and no significant differences between predicted and observed FSRs using 2 independent validation datasets. We found that cougars and canyon-dwelling bighorn sheep may select for environmental features that influence their detectability by GPS technology, mule deer may select against these features, and elk appear to be nonselective. We observed temporal patterns in missed fixes only for cougars. We provide a model for cougars, predicting fix success by time of day that is likely due to circadian changes in collar orientation and selection of daybed sites. We also provide a model predicting the probability of GPS fix acquisitions given environmental conditions, which had a strong relationship (r 2 = 0.82) with deployed collar FSRs across species.

  19. Internal Homogeneity, Descriptiveness, and Halo: Resurrecting Some Answers and Questions About the Structure of Job Performance Rating Categories.

    Science.gov (United States)

    Cooper, William H.

    1983-01-01

    Assessed the effects of two rating category attributes on halo in job performance ratings. Results suggested reducing halo by using rating categories that do not force raters to rely on their overall evaluation of the ratee, or use the same salient observations for rating job performance on multiple categories. (JAC)

  20. Detecting Distributed Scans Using High-Performance Query-DrivenVisualization

    Energy Technology Data Exchange (ETDEWEB)

    Stockinger, Kurt; Bethel, E. Wes; Campbell, Scott; Dart, Eli; Wu,Kesheng

    2006-09-01

    Modern forensic analytics applications, like network trafficanalysis, perform high-performance hypothesis testing, knowledgediscovery and data mining on very large datasets. One essential strategyto reduce the time required for these operations is to select only themost relevant data records for a given computation. In this paper, wepresent a set of parallel algorithms that demonstrate how an efficientselection mechanism -- bitmap indexing -- significantly speeds up acommon analysist ask, namely, computing conditional histogram on verylarge datasets. We present a thorough study of the performancecharacteristics of the parallel conditional histogram algorithms. Asacase study, we compute conditional histograms for detecting distributedscans hidden in a dataset consisting of approximately 2.5 billion networkconnection records. We show that these conditional histograms can becomputed on interactive timescale (i.e., in seconds). We also show how toprogressively modify the selection criteria to narrow the analysis andfind the sources of the distributed scans.

  1. A performance comparison of direct- and indirect-detection flat-panel imagers

    International Nuclear Information System (INIS)

    Partridge, M.; Hesse, B.-M.; Mueller, L.

    2002-01-01

    A comparison of the performance of a direct- and an indirect-detection amorphous silicon flat-panel X-ray imager is presented for a 6 MV beam. Experimental measurements of the noise characteristics, image lag, spectral response, spatial resolution and quantum efficiency are described, compared and discussed. The two systems are comprised of 512x512 pixel, 400 μm pitch, arrays of a-Si:H p-i-n photodiodes and thin-film transistors. In the direct-detection system, X-rays interact to produce electron/hole pairs directly in the silicon photodiodes. For the indirect-detection system, a phosphor screen converts energy from the incident X-rays into visible light, which is then detected by the photodiodes. Both systems are shown to be quantum noise limited, with the total electronic noise in the detector 10-15 times smaller than the Poisson noise level in detected signal. The measured lag for both systems is 1.0±0.1% or less in the first frame with subsequent signals decaying exponentially with frame read-out, with a half-life of between 3.3 and 3.8 frames. Both systems are demonstrated to have a pronounced sensitivity to low-energy multiply scattered photons, although this is shown to be effectively filtered out using a 2 mm copper build-up plate. The direct-detection system, with the 2 mm Cu build-up, shows greater sensitivity to scattered radiation than the indirect system. The spatial resolutions of both systems were effectively equal with an f 50 of 0.25 mm -1 when pixels are binned 2x2, although a slight contribution from optical scattering in the phosphor screen is seen for the indirect-detection system. The quantum efficiency of the direct-detection system is a factor of 0.45 lower than that of the indirect-detection system. The application of these detectors to megavoltage CT is discussed, with the conclusion that the indirect-detection system is to be preferred

  2. Impacts of Exchange Rate Regime Choice on Macroeconomic Performance in Emerging Markets

    Directory of Open Access Journals (Sweden)

    Rüstem Yanar

    2008-12-01

    Full Text Available This paper investigates the impact of exchange rate regime choice on macroeconomic performance after Bretton Woods in emerging market countries. It is studied especially inflation, growth and financial crises. It’s found that for emerging market countries, fixed regimes are associated with lower inflation than floats. On growth effect of exchange rate regime choice is not same all period. Fixed regimes are associated with faster growth but after 1990 fixed regimes brought about slower growth. At the same time, fixed exchange rate regimes are associated with financial fragility after 1990 in emerging markets

  3. High-Frame-Rate Power Doppler Ultrasound Is More Sensitive than Conventional Power Doppler in Detecting Rheumatic Vascularisation

    NARCIS (Netherlands)

    M. van der Ven (Myrthe); J.J. Luime (Jolanda); van der Velden, L.L. (Levinia L.); J.G. Bosch (Hans); J.M.W. Hazes (Mieke); H.J. Vos (Rik)

    2016-01-01

    textabstractEarly recognition of joint inflammation will increase treatment efficacy in rheumatoid arthritis (RA). Yet, conventional power Doppler (PD) ultrasound might not be sufficiently sensitive to detect minor inflammation. We investigated the sensitivity of high-frame rate Doppler, combined

  4. An Experimental Investigation of Leak Rate Performance of a Subscale Candidate Elastomer Docking Space Seal

    Science.gov (United States)

    Garafolo, Nicholas G.; Daniels, Christopher C.

    2011-01-01

    A novel docking seal was developed for the main interface seal of NASA s Low Impact Docking System (LIDS). This interface seal was designed to maintain acceptable leak rates while being exposed to the harsh environmental conditions of outer space. In this experimental evaluation, a candidate docking seal assembly called Engineering Development Unit (EDU58) was characterized and evaluated against the Constellation Project leak rate requirement. The EDU58 candidate seal assembly was manufactured from silicone elastomer S0383-70 vacuum molded in a metal retainer ring. Four seal designs were considered with unique characteristic heights. The leak rate performance was characterized through a mass point leak rate method by monitoring gas properties within an internal control volume. The leakage performance of the seals were described herein at representative docking temperatures of -50, +23, and +50 C for all four seal designs. Leak performance was also characterized at 100, 74, and 48 percent of full closure. For all conditions considered, the candidate seal assemblies met the Constellation Project leak rate requirement.

  5. Parallel segmented outlet flow high performance liquid chromatography with multiplexed detection

    International Nuclear Information System (INIS)

    Camenzuli, Michelle; Terry, Jessica M.; Shalliker, R. Andrew; Conlan, Xavier A.; Barnett, Neil W.; Francis, Paul S.

    2013-01-01

    Graphical abstract: -- Highlights: •Multiplexed detection for liquid chromatography. •‘Parallel segmented outlet flow’ distributes inner and outer portions of the analyte zone. •Three detectors were used simultaneously for the determination of opiate alkaloids. -- Abstract: We describe a new approach to multiplex detection for HPLC, exploiting parallel segmented outlet flow – a new column technology that provides pressure-regulated control of eluate flow through multiple outlet channels, which minimises the additional dead volume associated with conventional post-column flow splitting. Using three detectors: one UV-absorbance and two chemiluminescence systems (tris(2,2′-bipyridine)ruthenium(III) and permanganate), we examine the relative responses for six opium poppy (Papaver somniferum) alkaloids under conventional and multiplexed conditions, where approximately 30% of the eluate was distributed to each detector and the remaining solution directed to a collection vessel. The parallel segmented outlet flow mode of operation offers advantages in terms of solvent consumption, waste generation, total analysis time and solute band volume when applying multiple detectors to HPLC, but the manner in which each detection system is influenced by changes in solute concentration and solution flow rates must be carefully considered

  6. Parallel segmented outlet flow high performance liquid chromatography with multiplexed detection

    Energy Technology Data Exchange (ETDEWEB)

    Camenzuli, Michelle [Australian Centre for Research on Separation Science (ACROSS), School of Science and Health, University of Western Sydney (Parramatta), Sydney, NSW (Australia); Terry, Jessica M. [Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3216 (Australia); Shalliker, R. Andrew, E-mail: r.shalliker@uws.edu.au [Australian Centre for Research on Separation Science (ACROSS), School of Science and Health, University of Western Sydney (Parramatta), Sydney, NSW (Australia); Conlan, Xavier A.; Barnett, Neil W. [Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3216 (Australia); Francis, Paul S., E-mail: paul.francis@deakin.edu.au [Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3216 (Australia)

    2013-11-25

    Graphical abstract: -- Highlights: •Multiplexed detection for liquid chromatography. •‘Parallel segmented outlet flow’ distributes inner and outer portions of the analyte zone. •Three detectors were used simultaneously for the determination of opiate alkaloids. -- Abstract: We describe a new approach to multiplex detection for HPLC, exploiting parallel segmented outlet flow – a new column technology that provides pressure-regulated control of eluate flow through multiple outlet channels, which minimises the additional dead volume associated with conventional post-column flow splitting. Using three detectors: one UV-absorbance and two chemiluminescence systems (tris(2,2′-bipyridine)ruthenium(III) and permanganate), we examine the relative responses for six opium poppy (Papaver somniferum) alkaloids under conventional and multiplexed conditions, where approximately 30% of the eluate was distributed to each detector and the remaining solution directed to a collection vessel. The parallel segmented outlet flow mode of operation offers advantages in terms of solvent consumption, waste generation, total analysis time and solute band volume when applying multiple detectors to HPLC, but the manner in which each detection system is influenced by changes in solute concentration and solution flow rates must be carefully considered.

  7. An evidence accumulation model for conflict detection performance in a simulated air traffic control task.

    Science.gov (United States)

    Neal, Andrew; Kwantes, Peter J

    2009-04-01

    The aim of this article is to develop a formal model of conflict detection performance. Our model assumes that participants iteratively sample evidence regarding the state of the world and accumulate it over time. A decision is made when the evidence reaches a threshold that changes over time in response to the increasing urgency of the task. Two experiments were conducted to examine the effects of conflict geometry and timing on response proportions and response time. The model is able to predict the observed pattern of response times, including a nonmonotonic relationship between distance at point of closest approach and response time, as well as effects of angle of approach and relative velocity. The results demonstrate that evidence accumulation models provide a good account of performance on a conflict detection task. Evidence accumulation models are a form of dynamic signal detection theory, allowing for the analysis of response times as well as response proportions, and can be used for simulating human performance on dynamic decision tasks.

  8. A matched-filter algorithm to detect amperometric spikes resulting from quantal secretion.

    Science.gov (United States)

    Balaji Ramachandran, Supriya; Gillis, Kevin D

    2018-01-01

    Electrochemical microelectrodes located immediately adjacent to the cell surface can detect spikes of amperometric current during exocytosis as the transmitter released from a single vesicle is oxidized on the electrode surface. Automated techniques to detect spikes are needed in order to quantify the spike rate as a measure of the rate of exocytosis. We have developed a Matched Filter (MF) detection algorithm that scans the data set with a library of prototype spike templates while performing a least-squares fit to determine the amplitude and standard error. The ratio of the fit amplitude to the standard error constitutes a criterion score that is assigned for each time point and for each template. A spike is detected when the criterion score exceeds a threshold and the highest-scoring template and the time of peak score is identified. The search for the next spike commences only after the score falls below a second, lower threshold to reduce false positives. The approach was extended to detect spikes with double-exponential decays with the sum of two templates. Receiver Operating Characteristic plots (ROCs) demonstrate that the algorithm detects >95% of manually identified spikes with a false-positive rate of ∼2%. ROCs demonstrate that the MF algorithm performs better than algorithms that detect spikes based on a derivative-threshold approach. The MF approach performs well and leads into approaches to identify spike parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Performance comparison of two androgen receptor splice variant 7 (AR-V7) detection methods.

    Science.gov (United States)

    Bernemann, Christof; Steinestel, Julie; Humberg, Verena; Bögemann, Martin; Schrader, Andres Jan; Lennerz, Jochen K

    2018-01-23

    To compare the performance of two established androgen receptor splice variant 7 (AR-V7) mRNA detection systems, as paradoxical responses to next-generation androgen-deprivation therapy in AR-V7 mRNA-positive circulating tumour cells (CTC) of patients with castration-resistant prostate cancer (CRPC) could be related to false-positive classification using detection systems with different sensitivities. We compared the performance of two established mRNA-based AR-V7 detection technologies using either SYBR Green or TaqMan chemistries. We assessed in vitro performance using eight genitourinary cancer cell lines and serial dilutions in three AR-V7-positive prostate cancer cell lines, as well as in 32 blood samples from patients with CRPC. Both assays performed identically in the cell lines and serial dilutions showed identical diagnostic thresholds. Performance comparison in 32 clinical patient samples showed perfect concordance between the assays. In particular, both assays determined AR-V7 mRNA-positive CTCs in three patients with unexpected responses to next-generation anti-androgen therapy. Thus, technical differences between the assays can be excluded as the underlying reason for the unexpected responses to next-generation anti-androgen therapy in a subset of AR-V7 patients. Irrespective of the method used, patients with AR-V7 mRNA-positive CRPC should not be systematically precluded from an otherwise safe treatment option. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.

  10. Early Detection of At-Risk Undergraduate Students through Academic Performance Predictors

    Science.gov (United States)

    Rowtho, Vikash

    2017-01-01

    Undergraduate student dropout is gradually becoming a global problem and the 39 Small Islands Developing States (SIDS) are no exception to this trend. The purpose of this research was to develop a method that can be used for early detection of students who are at-risk of performing poorly in their undergraduate studies. A sample of 279 students…

  11. HPNAIDM: The High-Performance Network Anomaly/Intrusion Detection and Mitigation System

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yan [Northwesten University

    2013-12-05

    Identifying traffic anomalies and attacks rapidly and accurately is critical for large network operators. With the rapid growth of network bandwidth, such as the next generation DOE UltraScience Network, and fast emergence of new attacks/virus/worms, existing network intrusion detection systems (IDS) are insufficient because they: • Are mostly host-based and not scalable to high-performance networks; • Are mostly signature-based and unable to adaptively recognize flow-level unknown attacks; • Cannot differentiate malicious events from the unintentional anomalies. To address these challenges, we proposed and developed a new paradigm called high-performance network anomaly/intrustion detection and mitigation (HPNAIDM) system. The new paradigm is significantly different from existing IDSes with the following features (research thrusts). • Online traffic recording and analysis on high-speed networks; • Online adaptive flow-level anomaly/intrusion detection and mitigation; • Integrated approach for false positive reduction. Our research prototype and evaluation demonstrate that the HPNAIDM system is highly effective and economically feasible. Beyond satisfying the pre-set goals, we even exceed that significantly (see more details in the next section). Overall, our project harvested 23 publications (2 book chapters, 6 journal papers and 15 peer-reviewed conference/workshop papers). Besides, we built a website for technique dissemination, which hosts two system prototype release to the research community. We also filed a patent application and developed strong international and domestic collaborations which span both academia and industry.

  12. Computed tomography hepatic arteriography has a hepatic falciform artery detection rate that is much higher than that of digital subtraction angiography and 99mTc-MAA SPECT/CT: Implications for planning 90Y radioembolization?

    Energy Technology Data Exchange (ETDEWEB)

    Burgmans, M.C., E-mail: mburgmans@hotmail.com [Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Too, C.W., E-mail: too.chow.wei@singhealth.com.sg [Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Kao, Y.H., E-mail: yung.h.kao@gmail.com [Department of Nuclear Medicine and PET, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Goh, A.S.W., E-mail: anthony.goh.s.w@sgh.com.sg [Department of Nuclear Medicine and PET, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Chow, P.K.H., E-mail: gsupc@singnet.com.sg [Department of General Surgery, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Office of Clinical Sciences, Duke-NUS Graduate Medical School Singapore, 8 College Road, Singapore 169857 (Singapore); Department of Surgical Oncology, National Cancer Center Singapore, 11 Hospital Drive, Singapore 169610 (Singapore); Tan, B.S., E-mail: tan.bien.soo@sgh.com.sg [Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Tay, K.H., E-mail: tay.kiang.hiong@sgh.com.sg [Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore); Lo, R.H.G., E-mail: richard.lo.h.g@sgh.com.sg [Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608 (Singapore)

    2012-12-15

    Purpose: To compare the hepatic falciform artery (HFA) detection rates of digital subtraction angiography (DSA), computed tomography hepatic arteriography (CTHA) and 99mTc-macroaggregated albumin (99mTc-MAA) single photon emission computed tomography with integrated CT (SPECT/CT) and to correlate HFA patency with complication rates of yttrium-90 (90Y) radioembolization. Material and methods: From August 2008 to November 2010, 79 patients (range 23–83 years, mean 62.3 years; 67 male) underwent pre-treatment DSA, CTHA and 99mTc-MAA scintigraphy (planar/SPECT/CT) to assess suitability for radioembolization with 90Y resin microspheres. Thirty-seven patients were excluded from the study, because CTHA was performed with a catheter position that did not result in opacification of the liver parenchyma adjacent to the falciform ligament. DSA, CTHA and 99mTc-MAA SPECT/CT images and medical records were retrospectively reviewed. Results: A patent HFA was detected in 22 of 42 patients (52.3%). The HFA detection rates of DSA, CTHA and 99mTc-MAA SPECT/CT were 11.9%, 52.3% and 13.3%, respectively (p < 0.0001). An origin from the segment 4 artery was seen in 51.7% of HFAs. Prophylactic HFA coil-embolization prior to 90Y microspheres infusion was performed in 2 patients. Of the patients who underwent radioembolization with a patent HFA, none developed supra-umbilical radiation dermatitis. One patient experienced epigastric pain attributed to post-embolization syndrome and was managed conservatively. Conclusion: The HFA detection rate of CTHA is superior to that of DSA and 99mTc-MAA SPECT/CT. Complications related to non-target radiation of the HFA vascular territory rarely occur, even in patients undergoing radioembolization with a patent HFA.

  13. Computed tomography hepatic arteriography has a hepatic falciform artery detection rate that is much higher than that of digital subtraction angiography and 99mTc-MAA SPECT/CT: Implications for planning 90Y radioembolization?

    International Nuclear Information System (INIS)

    Burgmans, M.C.; Too, C.W.; Kao, Y.H.; Goh, A.S.W.; Chow, P.K.H.; Tan, B.S.; Tay, K.H.; Lo, R.H.G.

    2012-01-01

    Purpose: To compare the hepatic falciform artery (HFA) detection rates of digital subtraction angiography (DSA), computed tomography hepatic arteriography (CTHA) and 99mTc-macroaggregated albumin (99mTc-MAA) single photon emission computed tomography with integrated CT (SPECT/CT) and to correlate HFA patency with complication rates of yttrium-90 (90Y) radioembolization. Material and methods: From August 2008 to November 2010, 79 patients (range 23–83 years, mean 62.3 years; 67 male) underwent pre-treatment DSA, CTHA and 99mTc-MAA scintigraphy (planar/SPECT/CT) to assess suitability for radioembolization with 90Y resin microspheres. Thirty-seven patients were excluded from the study, because CTHA was performed with a catheter position that did not result in opacification of the liver parenchyma adjacent to the falciform ligament. DSA, CTHA and 99mTc-MAA SPECT/CT images and medical records were retrospectively reviewed. Results: A patent HFA was detected in 22 of 42 patients (52.3%). The HFA detection rates of DSA, CTHA and 99mTc-MAA SPECT/CT were 11.9%, 52.3% and 13.3%, respectively (p < 0.0001). An origin from the segment 4 artery was seen in 51.7% of HFAs. Prophylactic HFA coil-embolization prior to 90Y microspheres infusion was performed in 2 patients. Of the patients who underwent radioembolization with a patent HFA, none developed supra-umbilical radiation dermatitis. One patient experienced epigastric pain attributed to post-embolization syndrome and was managed conservatively. Conclusion: The HFA detection rate of CTHA is superior to that of DSA and 99mTc-MAA SPECT/CT. Complications related to non-target radiation of the HFA vascular territory rarely occur, even in patients undergoing radioembolization with a patent HFA.

  14. Real-time people and vehicle detection from UAV imagery

    Science.gov (United States)

    Gaszczak, Anna; Breckon, Toby P.; Han, Jiwan

    2011-01-01

    A generic and robust approach for the real-time detection of people and vehicles from an Unmanned Aerial Vehicle (UAV) is an important goal within the framework of fully autonomous UAV deployment for aerial reconnaissance and surveillance. Here we present an approach for the automatic detection of vehicles based on using multiple trained cascaded Haar classifiers with secondary confirmation in thermal imagery. Additionally we present a related approach for people detection in thermal imagery based on a similar cascaded classification technique combining additional multivariate Gaussian shape matching. The results presented show the successful detection of vehicle and people under varying conditions in both isolated rural and cluttered urban environments with minimal false positive detection. Performance of the detector is optimized to reduce the overall false positive rate by aiming at the detection of each object of interest (vehicle/person) at least once in the environment (i.e. per search patter flight path) rather than every object in each image frame. Currently the detection rate for people is ~70% and cars ~80% although the overall episodic object detection rate for each flight pattern exceeds 90%.

  15. The impact of ambient dose rate measuring network and precipitation radar system for detection of environmental radioactivity released by accident

    International Nuclear Information System (INIS)

    Bleher, M; Stoehlker, U.

    2003-01-01

    For the surveillance of environmental radioactivity, the German measuring network of BfS consists of more than 2000 stations where the ambient gamma dose rate is continuously measured. This network is a helpful tool to detect and localise enhanced environmental contamination from artificial radionuclides. The threshold for early warning is so low, that already an additional dose rate contribution of 0,07 μGy/h is detectable. However, this threshold is frequently exceeded due to precipitation events caused by washout of natural activity in air. Therefore, the precipitation radar system of the German Weather Service provides valuable information on the problem, whether the increase of the ambient dose rate is due to natural or man-made events. In case of an accidental release, the data of this radar system show small area precipitation events and potential local hot spots not detected by the measuring network. For the phase of cloud passage, the ambient dose rate measuring network provides a reliable database for the evaluation of the current situation and its further development. It is possible to compare measured data for dose rate with derived intervention levels for countermeasures like ''sheltering''. Thus, critical regions can be identified and it is possible to verify implemented countermeasures. During and after this phase of cloud passage the measured data of the monitoring network help to adapt the results of the national decision support systems PARK and RODOS. Therefore, it is necessary to derive the actual additional contribution to the ambient dose rate. Map representations of measured dose rate are rapidly available and helpful to optimise measurement strategies of mobile systems and collection strategies for samples of agricultural products. (orig.)

  16. Attributions or Retributions: Student Ratings and the Perceived Causes of Performance.

    Science.gov (United States)

    Theall, Michael; And Others

    The nature and extent of variations in student attributions about performance in their courses were studied, and the relationships between the attributions and responses on certain items of a student ratings questionnaire were determined. Causal or predictive relationships among these variables were also investigated. Data were collected using:…

  17. Amperometric Detection in Microchip Electrophoresis Devices: Effect of Electrode Material and Alignment on Analytical Performance

    Science.gov (United States)

    Fischer, David J.; Hulvey, Matthew K.; Regel, Anne R.; Lunte, Susan M.

    2012-01-01

    The fabrication and evaluation of different electrode materials and electrode alignments for microchip electrophoresis with electrochemical (EC) detection is described. The influences of electrode material, both metal and carbon-based, on sensitivity and limits of detection (LOD) were examined. In addition, the effects of working electrode alignment on analytical performance (in terms of peak shape, resolution, sensitivity, and LOD) were directly compared. Using dopamine (DA), norepinephrine (NE), and catechol (CAT) as test analytes, it was found that pyrolyzed photoresist electrodes with end-channel alignment yielded the lowest limit of detection (35 nM for DA). In addition to being easier to implement, end-channel alignment also offered better analytical performance than off-channel alignment for the detection of all three analytes. In-channel electrode alignment resulted in a 3.6-fold reduction in peak skew and reduced peak tailing by a factor of 2.1 for catechol in comparison to end-channel alignment. PMID:19802847

  18. Compressive Detection Using Sub-Nyquist Radars for Sparse Signals

    Directory of Open Access Journals (Sweden)

    Ying Sun

    2016-01-01

    Full Text Available This paper investigates the compression detection problem using sub-Nyquist radars, which is well suited to the scenario of high bandwidths in real-time processing because it would significantly reduce the computational burden and save power consumption and computation time. A compressive generalized likelihood ratio test (GLRT detector for sparse signals is proposed for sub-Nyquist radars without ever reconstructing the signal involved. The performance of the compressive GLRT detector is analyzed and the theoretical bounds are presented. The compressive GLRT detection performance of sub-Nyquist radars is also compared to the traditional GLRT detection performance of conventional radars, which employ traditional analog-to-digital conversion (ADC at Nyquist sampling rates. Simulation results demonstrate that the former can perform almost as well as the latter with a very small fraction of the number of measurements required by traditional detection in relatively high signal-to-noise ratio (SNR cases.

  19. PERFORMANCE EVALUATION AND RISK AVERSION RATE FOR SEVERAL STOCK INDICES IN INDONESIA STOCK EXCHANGE

    Directory of Open Access Journals (Sweden)

    Robiyanto Robiyanto

    2017-03-01

    Full Text Available There are numerous stock indices in Indonesia Stock Exchange. Several of them are LQ-45, MBX, DBX, JII, SRI-KEHATI, PEFINDO-25, BISNIS-27, IDX-30 and KOMPAS-100. Unfortunately there are limi­ted researches which have been done to measure those indices performance specifically. The same condition also occurs on risk aversion level usage in Indonesia Stock Exchange, only few numbers of researches use this me­a­surement in the portfolio valuation. Based on that, this research measured the performance and risk aversion rate of those indices in Indonesia Stock Exchange. The results of this study were SRI-KEHATI becomes the best performer with the highest risk aversion rate, while Jakarta Islamic Index (JII produces the lowest positive per­formance with the lowest risk aversion rate. This finding shows that sharia stocks’ characters (i.e. usury free could give relieveness and convenience regardless its per­formance.

  20. Improving Polyp Detection Algorithms for CT Colonography: Pareto Front Approach.

    Science.gov (United States)

    Huang, Adam; Li, Jiang; Summers, Ronald M; Petrick, Nicholas; Hara, Amy K

    2010-03-21

    We investigated a Pareto front approach to improving polyp detection algorithms for CT colonography (CTC). A dataset of 56 CTC colon surfaces with 87 proven positive detections of 53 polyps sized 4 to 60 mm was used to evaluate the performance of a one-step and a two-step curvature-based region growing algorithm. The algorithmic performance was statistically evaluated and compared based on the Pareto optimal solutions from 20 experiments by evolutionary algorithms. The false positive rate was lower (pPareto optimization process can effectively help in fine-tuning and redesigning polyp detection algorithms.

  1. Polarization-multiplexed rate-adaptive non-binary-quasi-cyclic-LDPC-coded multilevel modulation with coherent detection for optical transport networks.

    Science.gov (United States)

    Arabaci, Murat; Djordjevic, Ivan B; Saunders, Ross; Marcoccia, Roberto M

    2010-02-01

    In order to achieve high-speed transmission over optical transport networks (OTNs) and maximize its throughput, we propose using a rate-adaptive polarization-multiplexed coded multilevel modulation with coherent detection based on component non-binary quasi-cyclic (QC) LDPC codes. Compared to prior-art bit-interleaved LDPC-coded modulation (BI-LDPC-CM) scheme, the proposed non-binary LDPC-coded modulation (NB-LDPC-CM) scheme not only reduces latency due to symbol- instead of bit-level processing but also provides either impressive reduction in computational complexity or striking improvements in coding gain depending on the constellation size. As the paper presents, compared to its prior-art binary counterpart, the proposed NB-LDPC-CM scheme addresses the needs of future OTNs, which are achieving the target BER performance and providing maximum possible throughput both over the entire lifetime of the OTN, better.

  2. The Performance of the Four Anaerobic Blood Culture Bottles BacT/ALERT-FN, -FN Plus, BACTEC-Plus and -Lytic in Detection of Anaerobic Bacteria and Identification by Direct MALDI-TOF MS.

    Science.gov (United States)

    Almuhayawi, Mohammed; Altun, Osman; Abdulmajeed, Adam Dilshad; Ullberg, Måns; Özenci, Volkan

    2015-01-01

    Detection and identification of anaerobic bacteria in blood cultures (BC) is a well-recognized challenge in clinical microbiology. We studied 100 clinical anaerobic BC isolates to evaluate the performance of BacT/ALERT-FN, -FN Plus (BioMérieux), BACTEC-Plus and -Lytic (Becton Dickinson BioSciences) BC bottles in detection and time to detection (TTD) of anaerobic bacteria. BACTEC Lytic had higher detection rate (94/100, 94%) than BacT/ALERT FN Plus (80/100, 80%) (panaerobic bacteria among the remaining bottle types. The 67 anaerobic bacteria that signalled positive in all four bottle types were analyzed to compare the time to detection (TTD) and isolates were directly identified by MALDI-TOF MS. There was a significant difference in TTD among the four bottle types (panaerobic BC bottles are equally suitable for direct MALDI-TOF MS for rapid and reliable identification of common anaerobic bacteria. Further clinical studies are warranted to investigate the performance of anaerobic BC bottles in detection of anaerobic bacteria and identification by direct MALDI-TOF MS.

  3. Screen-detected versus interval cancers: Effect of imaging modality and breast density in the Flemish Breast Cancer Screening Programme.

    Science.gov (United States)

    Timmermans, Lore; Bleyen, Luc; Bacher, Klaus; Van Herck, Koen; Lemmens, Kim; Van Ongeval, Chantal; Van Steen, Andre; Martens, Patrick; De Brabander, Isabel; Goossens, Mathieu; Thierens, Hubert

    2017-09-01

    To investigate if direct radiography (DR) performs better than screen-film mammography (SF) and computed radiography (CR) in dense breasts in a decentralized organised Breast Cancer Screening Programme. To this end, screen-detected versus interval cancers were studied in different BI-RADS density classes for these imaging modalities. The study cohort consisted of 351,532 women who participated in the Flemish Breast Cancer Screening Programme in 2009 and 2010. Information on screen-detected and interval cancers, breast density scores of radiologist second readers, and imaging modality was obtained by linkage of the databases of the Centre of Cancer Detection and the Belgian Cancer Registry. Overall, 67% of occurring breast cancers are screen detected and 33% are interval cancers, with DR performing better than SF and CR. The interval cancer rate increases gradually with breast density, regardless of modality. In the high-density class, the interval cancer rate exceeds the cancer detection rate for SF and CR, but not for DR. DR is superior to SF and CR with respect to cancer detection rates for high-density breasts. To reduce the high interval cancer rate in dense breasts, use of an additional imaging technique in screening can be taken into consideration. • Interval cancer rate increases gradually with breast density, regardless of modality. • Cancer detection rate in high-density breasts is superior in DR. • IC rate exceeds CDR for SF and CR in high-density breasts. • DR performs better in high-density breasts for third readings and false-positives.

  4. Academic Performance and Pass Rates: Comparison of Three First-Year Life Science Courses

    Science.gov (United States)

    Downs, C. T.

    2009-01-01

    First year students' academic performance in three Life Science courses (Botany, Zoology and Bioscience) was compared. Pass rates, as well as the means and distributions of final marks were analysed. Of the three components (coursework, practical and theory examinations) contributing to the final mark of each course, students performed best in the…

  5. Parametric Analysis of Surveillance Quality and Level and Quality of Intent Information and Their Impact on Conflict Detection Performance

    Science.gov (United States)

    Guerreiro, Nelson M.; Butler, Ricky W.; Hagen, George E.; Maddalon, Jeffrey M.; Lewis, Timothy A.

    2016-01-01

    A loss-of-separation (LOS) is said to occur when two aircraft are spatially too close to one another. A LOS is the fundamental unsafe event to be avoided in air traffic management and conflict detection (CD) is the function that attempts to predict these LOS events. In general, the effectiveness of conflict detection relates to the overall safety and performance of an air traffic management concept. An abstract, parametric analysis was conducted to investigate the impact of surveillance quality, level of intent information, and quality of intent information on conflict detection performance. The data collected in this analysis can be used to estimate the conflict detection performance under alternative future scenarios or alternative allocations of the conflict detection function, based on the quality of the surveillance and intent information under those conditions.Alternatively, this data could also be used to estimate the surveillance and intent information quality required to achieve some desired CD performance as part of the design of a new separation assurance system.

  6. Detection Rate and Clinical Impact of Respiratory Viruses in Children with Kawasaki Disease

    Directory of Open Access Journals (Sweden)

    Ja Hye Kim

    2012-12-01

    Full Text Available &lt;B&gt;Purpose:&lt;/B&gt; The purpose of this prospective case-control study was to survey the detection rate of respiratory viruses in children with Kawasaki disease (KD by using multiplex reverse transcriptasepolymerase chain reaction (RT-PCR, and to investigate the clinical implications of the prevalence of respiratory viruses during the acute phase of KD. &lt;B&gt;Methods:&lt;/B&gt; RT-PCR assays were carried out to screen for the presence of respiratory syncytial virus A and B, adenovirus, rhinovirus, parainfluenza viruses 1 to 4, influenza virus A and B, metapneumovirus, bocavirus, coronavirus OC43/229E and NL63, and enterovirus in nasopharyngeal secretions of 55 KD patients and 78 control subjects. &lt;B&gt;Results:&lt;/B&gt; Virus detection rates in KD patients and control subjects were 32.7% and 30.8%, respectively (P=0.811. However, there was no significant association between the presence of any of the 15 viruses and the incidence of KD. Comparisons between the 18 patients with positive RT-PCR results and the other 37 KD patients revealed no significant differences in terms of clinical findings (including the prevalence of incomplete presentation of the disease and coronary artery diameter. &lt;B&gt;Conclusion:&lt;/B&gt; A positive RT-PCR for currently epidemic respiratory viruses should not be used as an evidence against the diagnosis of KD. These viruses were not associated with the incomplete presentation of KD and coronary artery dilatation.

  7. Leak detection capability in CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Azer, N.; Barber, D.H.; Boucher, P.J. [and others

    1997-04-01

    This paper addresses the moisture leak detection capability of Ontario Hydro CANDU reactors which has been demonstrated by performing tests on the reactor. The tests confirmed the response of the annulus gas system (AGS) to the presence of moisture injected to simulate a pressure tube leak and also confirmed the dew point response assumed in leak before break assessments. The tests were performed on Bruce A Unit 4 by injecting known and controlled rates of heavy water vapor. To avoid condensation during test conditions, the amount of moisture which could be injected was small (2-3.5 g/hr). The test response demonstrated that the AGS is capable of detecting and annunciating small leaks. Thus confidence is provided that it would alarm for a growing pressure tube leak where the leak rate is expected to increase to kg/hr rapidly. The measured dew point response was close to that predicted by analysis.

  8. Leak detection capability in CANDU reactors

    International Nuclear Information System (INIS)

    Azer, N.; Barber, D.H.; Boucher, P.J.

    1997-01-01

    This paper addresses the moisture leak detection capability of Ontario Hydro CANDU reactors which has been demonstrated by performing tests on the reactor. The tests confirmed the response of the annulus gas system (AGS) to the presence of moisture injected to simulate a pressure tube leak and also confirmed the dew point response assumed in leak before break assessments. The tests were performed on Bruce A Unit 4 by injecting known and controlled rates of heavy water vapor. To avoid condensation during test conditions, the amount of moisture which could be injected was small (2-3.5 g/hr). The test response demonstrated that the AGS is capable of detecting and annunciating small leaks. Thus confidence is provided that it would alarm for a growing pressure tube leak where the leak rate is expected to increase to kg/hr rapidly. The measured dew point response was close to that predicted by analysis

  9. Estimating dual deposit insurance premium rates and forecasting non-performing loans: Two new models

    OpenAIRE

    Yoshino, Naoyuki; Taghizadeh-Hesary, Farhad; Nili, Farhad

    2015-01-01

    Risky banks that endanger the stability of the financial system should pay higher deposit insurance premiums than healthy banks and other financial institutions that have shown good financial performance. It is necessary, therefore, to have at least a dual fair premium rate system. In this paper, we develop a model for calculating dual fair premium rates. Our definition of a fair premium rate in this paper is a rate that could cover the operational expenditures of the deposit insuring organiz...

  10. Fast detection of atrazine in corn using thermometric biosensors.

    Science.gov (United States)

    Qie, Zhiwei; Ning, Baoan; Liu, Ming; Bai, Jialei; Peng, Yuan; Song, Nan; Lv, Zhiqiang; Wang, Ying; Sun, Siming; Su, Xuan; Zhang, Yihong; Gao, Zhixian

    2013-09-07

    Fast detection is important in screening large-scale samples. This study establishes a direct competitive ELISA method (dcTELISA) based on an enzyme thermistor for fast atrazine (ATZ) detection. ATZ competes with β-lactamase-labeled ATZ (ATZ-E) for the binding sites on anti-ATZ monoclonal antibody (mAb). The mAb are covalently bound to Controlled Pore Glass (CPG) in an immunoreactor to form immunocomplexes with ATZ and ATZ-E. Several parameters of biosensor performance were optimized, such as the ATZ-E concentration, concentration and nature of the substrate, flow rate, and effect of temperature on the sensor response. After optimization, the assay time for a single sample was 12 min. The work process and result were compared with those of high-performance liquid chromatography (HPLC). The detection results exhibited a recovery rate of 88% to 107% in ATZ-spiked fresh cut corn stalks and silage samples. The results obtained via dcTELISA had good correlation with that of HPLC, and the biosensor response was reproducible and stable even when used continuously for over 4 months. All these properties suggested that the fast detection method, dcTELISA, may be used to detect pesticide residue in large-scale samples.

  11. Prospective memory, working memory, retrospective memory and self-rated memory performance in persons with intellectual disability

    OpenAIRE

    Levén, Anna; Lyxell, Björn; Andersson, Jan; Danielsson, Henrik; Rönnberg, Jerker

    2008-01-01

    The purpose of the present study was to examine the relationship between prospective memory, working memory, retrospective memory and self-rated memory capacity in adults with and without intellectual disability. Prospective memory was investigated by means of a picture-based task. Working memory was measured as performance on span tasks. Retrospective memory was scored as recall of subject performed tasks. Self-ratings of memory performance were based on the prospective and retrospective mem...

  12. Assessing Bus Performance Rating in Kajang, Selangor

    Science.gov (United States)

    Norhisham, S.; Ismail, A.; Sidek, L. M.; Borhan, M. N.; Zaini, N.; Yen, A. T. G.

    2018-04-01

    The Transit Capacity and Quality of Service Manual (TCQSM) was chosen based on the review with four manuals and guidelines for the method will be applied. Six (6) attributes, namely Hours of Service, Passenger Load, Transit Auto Travel Time, Service Frequency, Punctuality Performance and Service Coverage were chosen for evaluation.[6][7][8]. A total of three (3) operators with seven (7) routes were identified in Kajang. Based on the final results, the Quality of Service (QOS) findings was rated as D, which was regarded as minimum or satisfactory. Most stakeholders’ recommendations were: for the operators to provide information on bus scheduling and have accurate information for the passengers. It was suggested that in future this study can be extended to all routes and could be repeated after the opening of the Mass Rapid Transit (MRT) stations in Kajang, so as to provide a comparison and better evaluation of the public buses in Kajang.

  13. Low-sampling-rate ultra-wideband digital receiver using equivalent-time sampling

    KAUST Repository

    Ballal, Tarig

    2014-09-01

    In this paper, we propose an all-digital scheme for ultra-wideband symbol detection. In the proposed scheme, the received symbols are sampled many times below the Nyquist rate. It is shown that when the number of symbol repetitions, P, is co-prime with the symbol duration given in Nyquist samples, the receiver can sample the received data P times below the Nyquist rate, without loss of fidelity. The proposed scheme is applied to perform channel estimation and binary pulse position modulation (BPPM) detection. Results are presented for two receivers operating at two different sampling rates that are 10 and 20 times below the Nyquist rate. The feasibility of the proposed scheme is demonstrated in different scenarios, with reasonable bit error rates obtained in most of the cases.

  14. Low-sampling-rate ultra-wideband digital receiver using equivalent-time sampling

    KAUST Repository

    Ballal, Tarig; Al-Naffouri, Tareq Y.

    2014-01-01

    In this paper, we propose an all-digital scheme for ultra-wideband symbol detection. In the proposed scheme, the received symbols are sampled many times below the Nyquist rate. It is shown that when the number of symbol repetitions, P, is co-prime with the symbol duration given in Nyquist samples, the receiver can sample the received data P times below the Nyquist rate, without loss of fidelity. The proposed scheme is applied to perform channel estimation and binary pulse position modulation (BPPM) detection. Results are presented for two receivers operating at two different sampling rates that are 10 and 20 times below the Nyquist rate. The feasibility of the proposed scheme is demonstrated in different scenarios, with reasonable bit error rates obtained in most of the cases.

  15. Performance evaluation for epileptic electroencephalogram (EEG) detection by using Neyman-Pearson criteria and a support vector machine

    Science.gov (United States)

    Wang, Chun-mei; Zhang, Chong-ming; Zou, Jun-zhong; Zhang, Jian

    2012-02-01

    The diagnosis of several neurological disorders is based on the detection of typical pathological patterns in electroencephalograms (EEGs). This is a time-consuming task requiring significant training and experience. A lot of effort has been devoted to developing automatic detection techniques which might help not only in accelerating this process but also in avoiding the disagreement among readers of the same record. In this work, Neyman-Pearson criteria and a support vector machine (SVM) are applied for detecting an epileptic EEG. Decision making is performed in two stages: feature extraction by computing the wavelet coefficients and the approximate entropy (ApEn) and detection by using Neyman-Pearson criteria and an SVM. Then the detection performance of the proposed method is evaluated. Simulation results demonstrate that the wavelet coefficients and the ApEn are features that represent the EEG signals well. By comparison with Neyman-Pearson criteria, an SVM applied on these features achieved higher detection accuracies.

  16. Pilot simulation study using meat inspection data for syndromic surveillance: use of whole carcass condemnation of adult cattle to assess the performance of several algorithms for outbreak detection.

    Science.gov (United States)

    Dupuy, C; Morignat, E; Dorea, F; Ducrot, C; Calavas, D; Gay, E

    2015-09-01

    The objective of this study was to assess the performance of several algorithms for outbreak detection based on weekly proportions of whole carcass condemnations. Data from one French slaughterhouse over the 2005-2009 period were used (177 098 slaughtered cattle, 0.97% of whole carcass condemnations). The method involved three steps: (i) preparation of an outbreak-free historical baseline over 5 years, (ii) simulation of over 100 years of baseline time series with injection of artificial outbreak signals with several shapes, durations and magnitudes, and (iii) assessment of the performance (sensitivity, specificity, outbreak detection precocity) of several algorithms to detect these artificial outbreak signals. The algorithms tested included the Shewart p chart, confidence interval of the negative binomial model, the exponentially weighted moving average (EWMA); and cumulative sum (CUSUM). The highest sensitivity was obtained using a negative binomial algorithm and the highest specificity with CUSUM or EWMA. EWMA sensitivity was too low to select this algorithm for efficient outbreak detection. CUSUM's performance was complementary to the negative binomial algorithm. The use of both algorithms on real data for a prospective investigation of the whole carcass condemnation rate as a syndromic surveillance indicator could be relevant. Shewart could also be a good option considering its high sensitivity and simplicity of implementation.

  17. ANSI/ASHRAE/IES Standard 90.1-2010 Performance Rating Method Reference Manual

    Energy Technology Data Exchange (ETDEWEB)

    Goel, Supriya [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-05-01

    This document is intended to be a reference manual for the Appendix G Performance Rating Method (PRM) of ANSI/ASHRAE/IES Standard 90.1- 2010 (Standard 90.1-2010).The PRM is used for rating the energy efficiency of commercial and high-rise residential buildings with designs that exceed the requirements of Standard 90.1. The procedures and processes described in this manual are designed to provide consistency and accuracy by filling in gaps and providing additional details needed by users of the PRM. It should be noted that this document is created independently from ASHRAE and SSPC 90.1 and is not sanctioned nor approved by either of those entities . Potential users of this manual include energy modelers, software developers and implementers of “beyond code” energy programs. Energy modelers using ASHRAE Standard 90.1-2010 for beyond code programs can use this document as a reference manual for interpreting requirements of the Performance Rating method. Software developers, developing tools for automated creation of the baseline model can use this reference manual as a guideline for developing the rules for the baseline model.

  18. Non-parametric early seizure detection in an animal model of temporal lobe epilepsy

    Science.gov (United States)

    Talathi, Sachin S.; Hwang, Dong-Uk; Spano, Mark L.; Simonotto, Jennifer; Furman, Michael D.; Myers, Stephen M.; Winters, Jason T.; Ditto, William L.; Carney, Paul R.

    2008-03-01

    The performance of five non-parametric, univariate seizure detection schemes (embedding delay, Hurst scale, wavelet scale, nonlinear autocorrelation and variance energy) were evaluated as a function of the sampling rate of EEG recordings, the electrode types used for EEG acquisition, and the spatial location of the EEG electrodes in order to determine the applicability of the measures in real-time closed-loop seizure intervention. The criteria chosen for evaluating the performance were high statistical robustness (as determined through the sensitivity and the specificity of a given measure in detecting a seizure) and the lag in seizure detection with respect to the seizure onset time (as determined by visual inspection of the EEG signal by a trained epileptologist). An optimality index was designed to evaluate the overall performance of each measure. For the EEG data recorded with microwire electrode array at a sampling rate of 12 kHz, the wavelet scale measure exhibited better overall performance in terms of its ability to detect a seizure with high optimality index value and high statistics in terms of sensitivity and specificity.

  19. Detection of TTV-DNA in PBMC using digoxigenin labelled probe by in situ hybridization

    International Nuclear Information System (INIS)

    Liu Yang; Qi Qige

    2002-01-01

    To determine TTV-DNA in PBMC in patients with viral hepatitis, a study of in situ hybridization using digoxigenin labelled probe by PCR method to the TTV ORF1 region was performed on PBMC. Results showed that the detection rate of TTV-DNA using double-stranded probe in TTV-DNA positive group in sera was 58.06 (18/31), and the detection rate of TTV-DNA using double-stranded probe in TTV-DNA negative group in sera was 27.59 (8/29). For TTV-DNA positive group detected by double- stranded probe, then we use negative- stranded probe to detect their replication. The detection rate was 22.2%(4/18). Conclusions: TTV can infect PBMC and replicate in PBMC

  20. Symbol error rate performance evaluation of the LM37 multimegabit telemetry modulator-demodulator unit

    Science.gov (United States)

    Malek, H.

    1981-01-01

    The LM37 multimegabit telemetry modulator-demodulator unit was tested for evaluation of its symbol error rate (SER) performance. Using an automated test setup, the SER tests were carried out at various symbol rates and signal-to-noise ratios (SNR), ranging from +10 to -10 dB. With the aid of a specially designed error detector and a stabilized signal and noise summation unit, measurement of the SER at low SNR was possible. The results of the tests show that at symbol rates below 20 megasymbols per second (MS)s) and input SNR above -6 dB, the SER performance of the modem is within the specified 0.65 to 1.5 dB of the theoretical error curve. At symbol rates above 20 MS/s, the specification is met at SNR's down to -2 dB. The results of the SER tests are presented with the description of the test setup and the measurement procedure.

  1. Microcontroller-based real-time QRS detection.

    Science.gov (United States)

    Sun, Y; Suppappola, S; Wrublewski, T A

    1992-01-01

    The authors describe the design of a system for real-time detection of QRS complexes in the electrocardiogram based on a single-chip microcontroller (Motorola 68HC811). A systematic analysis of the instrumentation requirements for QRS detection and of the various design techniques is also given. Detection algorithms using different nonlinear transforms for the enhancement of QRS complexes are evaluated by using the ECG database of the American Heart Association. The results show that the nonlinear transform involving multiplication of three adjacent, sign-consistent differences in the time domain gives a good performance and a quick response. When implemented with an appropriate sampling rate, this algorithm is also capable of rejecting pacemaker spikes. The eight-bit single-chip microcontroller provides sufficient throughput and shows a satisfactory performance. Implementation of multiple detection algorithms in the same system improves flexibility and reliability. The low chip count in the design also favors maintainability and cost-effectiveness.

  2. Anthropometric and performance measures to study talent detection in youth volleyball.

    Science.gov (United States)

    Melchiorri, Giovanni; Viero, Valerio; Triossi, Tamara; Annino, Giuseppe; Padua, Elvira; Tancredi, Virginia

    2017-12-01

    The aim of this work was to study anthropometric and performance measurements in 60 young male volleyball players (YV) and 60 youth not active in the sport (YNA) to assess which of these would be more useful to study the characteristics of potential performers. Eight measures to assess anthropometric characteristics, six performance measures and two tests for joint mobility were used. Also relative age and level of maturation were assessed. The anthropometric variables, relative age and level of maturation measured did not show statistically significant differences between groups. The YV and YNA groups showed differences in the performance measures. YV group was characterized by a better performance of the ability to repeat short sprints, of the upper limbs, abdominal muscles and lower limbs, with a medium effect size (Shuttle Running Test: 0.6; Push-Up: 0.5; Sit-Up: 0.4; counter movement jump: 0.4). These performance variables were very sensitive and specific: the SRT measurement had the best positive likelihood ratio that indicates the utility of the test in identifying type of players (YV and YNA). In talent detection in youth volleyball, in the 11-13 age range, performance variables should be preferred to anthropometric ones.

  3. The Colonoscopist's Expertise Affects the Characteristics of Detected Polyps

    Directory of Open Access Journals (Sweden)

    Da Kyoung Jung

    2016-01-01

    Full Text Available Background/Aims: The influence of the endoscopist on the polyp detection rate (PDR is underappreciated in clinical practice. Moreover, flat lesions or lesions of the proximal colon are more difficult to detect. Here, we evaluated the differences in the PDR and the characteristics of detected polyps according to the experience of the colonoscopist. Methods: We collected data on 2,549 patients who underwent screening colonoscopy performed by three fellows. The PDR was calculated according to the percentage of patients who had at least one polyp (method A and according to the percentage of detected lesions (method B. The primary outcome included the change in the PDR, and the secondary outcome included the change in the characteristics of the detected polyps with increasing experience of the colonoscopist. Results: No proportional correlation was found between the PDR and increasing experience in colonoscopy with method A; however, with method B, the PDR increased after 400 colonoscopies (p=0.0209. With method B, the detection rates of small polyps (<5 mm (p=0.0015 and polyps in proximal sites (p=0.0050 increased after 300 colonoscopies. Conclusions: Our study demonstrated that the quality of a colonoscopy, measured by using the PDR, may increase when performed by experienced fellows.

  4. Recent Progress in Technology of Leak detection

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H. K.; Kim, S. H.; Cho, J. W.; Joo, Y. S.; Yang, D. J

    2005-07-15

    It is very important to check for leakage points of fluids and gases on primary pressure boundary of nuclear power plants in order to maintain and manage various structures safely. Even though much investigation has been performed by a number of researchers, there are a lot of problems to detect the leakage under some areas to which people can not approach. In particular, it is certainly necessary to find the leakage point in order to repair and replace the pressure boundaries. In this report, the basic principle and application situations for the development of the leak detection system which can detect micro-leaks are introduced. As the technologies and performances of recent sensors have been improving, the application range of leak detection has been increasing steadily. Therefore the sensor technologies written in this report will be able to contribute to nuclear safety to detect the leakage rate and the leakage point with an on-line monitoring system in the near future.

  5. A New Approach to Performing Bundle Adjustment for Time Series UAV Images 3D Building Change Detection

    Directory of Open Access Journals (Sweden)

    Wenzhuo Li

    2017-06-01

    Full Text Available Successful change detection in multi-temporal images relies on high spatial co-registration accuracy. However, co-registration accuracy alone cannot meet the needs of change detection when using several ground control points to separately geo-reference multi-temporal images from unmanned aerial vehicles (UAVs. This letter reports on a new approach to perform bundle adjustment—named united bundle adjustment (UBA—to solve this co-registration problem for change detection in multi-temporal UAV images. In UBA, multi-temporal UAV images are matched with each other to construct a unified tie point net. One single bundle adjustment process is performed on the unified tie point net, placing every image into the same coordinate system and thus automatically accomplishing spatial co-registration. We then perform change detection using both orthophotos and three-dimensional height information derived from dense image matching techniques. Experimental results show that UBA co-registration accuracy is higher than the accuracy of commonly-used approaches for multi-temporal UAV images. Our proposed preprocessing method extends the capacities of consumer-level UAVs so they can eventually meet the growing need for automatic building change detection and dynamic monitoring using only RGB band images.

  6. Impact of window decrement rate on TCP performance in an adhoc network

    Science.gov (United States)

    Suherman; Hutasuhut, Arief T. W.; Badra, Khaldun; Al-Akaidi, Marwan

    2017-09-01

    Transmission control protocol (TCP) is a reliable transport protocol handling end to end connection in TCP/IP stack. It works well in copper or optical fibre link, but experiences increasing delay in wireless network. Further, TCP experiences multiple retransmissions due to higher collision probability within wireless network. The situation may get worsen in an ad hoc network. This paper examines the impact half window or window reduction rate to the overall TCP performances. The evaluation using NS-2 simulator shows that the smaller the window decrement rate results the smaller end to end delay. Delay is reduced to 17.05% in average when window decrement rate decreases. Average jitter also decreases 4.15%, while packet loss is not affected.

  7. Test performance of faecal occult blood testing for the detection of bowel cancer in people with chronic kidney disease (DETECT protocol

    Directory of Open Access Journals (Sweden)

    Williams Narelle

    2011-06-01

    Full Text Available Abstract Background Cancer is a major cause of mortality and morbidity in patients with chronic kidney disease (CKD. In patients without kidney disease, screening is a major strategy for reducing the risk of cancer and improving the health outcomes for those who developed cancers by detecting treatable cancers at an early stage. Among those with CKD, the effectiveness, the efficacy and patients' preferences for cancer screening are unknown. Methods/Design This work describes the protocol for the DETECT study examining the effectiveness, efficiency and patient's perspectives of colorectal cancer screening using immunochemical faecal occult blood testing (iFOBT for people with CKD. The aims of the DETECT study are 1 to determine the test performance characteristics of iFOBT screening in individuals with CKD, 2 to estimate the incremental costs and health benefits of iFOBT screening in CKD compared to no screening and 3 to elicit patients' perspective for colorectal cancer screening in the CKD population. Three different study designs will be used to explore the uncertainties surrounding colorectal cancer screening in CKD. A diagnostic test accuracy study of iFOBT screening will be conducted across all stages of CKD in patients ages 35-70. Using individually collected direct healthcare costs and outcomes from the diagnostic test accuracy study, cost-utility and cost-effective analyses will be performed to estimate the costs and health benefits of iFOBT screening in CKD. Qualitative in-depth interviews will be undertaken in a subset of participants from the diagnostic test accuracy study to investigate the perspectives, experiences, attitudes and beliefs about colorectal cancer screening among individuals with CKD. Discussion The DETECT study will target the three major unknowns about early cancer detection in CKD. Findings from our study will provide accurate and definitive estimates of screening efficacy and efficiency for colorectal cancer, and

  8. Imaging, object detection, and change detection with a polarized multistatic GPR array

    Science.gov (United States)

    Beer, N. Reginald; Paglieroni, David W.

    2015-07-21

    A polarized detection system performs imaging, object detection, and change detection factoring in the orientation of an object relative to the orientation of transceivers. The polarized detection system may operate on one of several modes of operation based on whether the imaging, object detection, or change detection is performed separately for each transceiver orientation. In combined change mode, the polarized detection system performs imaging, object detection, and change detection separately for each transceiver orientation, and then combines changes across polarizations. In combined object mode, the polarized detection system performs imaging and object detection separately for each transceiver orientation, and then combines objects across polarizations and performs change detection on the result. In combined image mode, the polarized detection system performs imaging separately for each transceiver orientation, and then combines images across polarizations and performs object detection followed by change detection on the result.

  9. Customer and performance rating in QFD using SVM classification

    Science.gov (United States)

    Dzulkifli, Syarizul Amri; Salleh, Mohd Najib Mohd; Leman, A. M.

    2017-09-01

    In a classification problem, where each input is associated to one output. Training data is used to create a model which predicts values to the true function. SVM is a popular method for binary classification due to their theoretical foundation and good generalization performance. However, when trained with noisy data, the decision hyperplane might deviate from optimal position because of the sum of misclassification errors in the objective function. In this paper, we introduce fuzzy in weighted learning approach for improving the accuracy of Support Vector Machine (SVM) classification. The main aim of this work is to determine appropriate weighted for SVM to adjust the parameters of learning method from a given set of noisy input to output data. The performance and customer rating in Quality Function Deployment (QFD) is used as our case study to determine implementing fuzzy SVM is highly scalable for very large data sets and generating high classification accuracy.

  10. Graphene oxide-coated stir bar sorptive extraction of trace aflatoxins from soy milk followed by high performance liquid chromatography-laser-induced fluorescence detection.

    Science.gov (United States)

    Ma, Haiyan; Ran, Congcong; Li, Mengjiao; Gao, Jinglin; Wang, Xinyu; Zhang, Lina; Bian, Jing; Li, Junmei; Jiang, Ye

    2018-04-01

    Mycotoxins are potential food pollutants produced by fungi. Among them, aflatoxins (AFs) are the most toxic. Therefore, AFs were selected as models, and a sensitive, simple and green graphene oxide (GO)-based stir bar sorptive extraction (SBSE) method was developed for extraction and determination of AFs with high performance liquid chromatography-laser-induced fluorescence detector (HPLC-LIF). This method improved the sensitivity of AFs detection and solved the deposition difficulty of the direct use of GO as adsorbent. Several parameters including a spiked amount of NaCl, stirring rate, extraction time and desorption time were investigated. Under optimal conditions, the quantitative method had low limits of detection of 2.4-8.0 pg/mL, which were better than some reported AFs analytical methods. The developed method has been applied to soy milk samples with good recoveries ranging from 80.5 to 102.3%. The prepared GO-based SBSE can be used as a sensitive screening technique for detecting AFs in soy milk.

  11. Incorporating an Exercise Detection, Grading, and Hormone Dosing Algorithm Into the Artificial Pancreas Using Accelerometry and Heart Rate

    OpenAIRE

    Jacobs, Peter G.; Resalat, Navid; El Youssef, Joseph; Reddy, Ravi; Branigan, Deborah; Preiser, Nicholas; Condon, John; Castle, Jessica

    2015-01-01

    In this article, we present several important contributions necessary for enabling an artificial endocrine pancreas (AP) system to better respond to exercise events. First, we show how exercise can be automatically detected using body-worn accelerometer and heart rate sensors. During a 22 hour overnight inpatient study, 13 subjects with type 1 diabetes wearing a Zephyr accelerometer and heart rate monitor underwent 45 minutes of mild aerobic treadmill exercise while controlling their glucose ...

  12. Effect of layer number on recovery rate of WS{sub 2} nanosheets for ammonia detection at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Ziyu [State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University, Wuhan 430062 (China); Zeng, Dawen, E-mail: dwzeng@mail.hust.edu.cn [State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University, Wuhan 430062 (China); Zhang, Jia; Wu, Congyi; Wen, Yanwei; Shan, Bin; Xie, Changsheng [State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074 (China)

    2017-08-31

    Highlights: • Reasons for room-temperature difficult recovery of WS{sub 2} sensors for NH{sub 3} detection. • The excellent recovery within 271.9 s was observed for single-layer WS{sub 2} sensor. • The recovery time of WS{sub 2} sensor has a anti-linear relation with number of layer. - Abstract: Tungsten disulfide (WS{sub 2}), as a representative layered transition metal dichalcogenides (TMDs), is expected as a promising candidate for high-performance NH{sub 3} sensor at room temperature. Unfortunately, the common WS{sub 2} based NH{sub 3} sensors are difficult to recovery at room temperature, which severely limits its application. Hence, how to improve recovery has become an urgent problem to be solved. Herein, we prepare five types of WS{sub 2} nanosheets with different layer numbers from bulk to monolayer, and find that the recovery time of NH{sub 3} gas sensor is rapidly linear shorten as the number of layers decreasing. Through the first-principles calculation of the interaction between NH{sub 3} and WS{sub 2} substance, the different binding energy between ammonia and the surface (−0.179 eV) and interlayer (−0.356 eV) of layered WS{sub 2}, as well as the different electron transfer way, should be responsible for the difficult recovery rate of various WS{sub 2} samples. Therefore, reducing the number of layer of WS{sub 2} is a promising approach to speed up recovery. Based on this conclusion, we successfully prepare a fast recoverable ammonia gas sensor based on single layer WS{sub 2}, which exhibits exciting fast recovery within 271.9 s at room temperature without any condition. Moreover, our work also can act as a reference for other gas detection of TMDs based gas sensor to improve the gas performance at room-temperature.

  13. Cooperative decoding in femtocell networks: Performance-complexity tradeoff

    KAUST Repository

    Benkhelifa, Fatma

    2012-06-01

    Femtocells, which are low cost low power, stand alone cellular access points, are a potential solution to provide good indoor coverage with high data rate. However, the femtocell deployment may also increase the co-channel interference (CCI) by reducing the distance reuse of the spectrum. In this paper, we introduce methods to cancel out the interference among the femtocells while considering that macrocells operate orthogonally to the femtocells. The femtocells may also cooperate through joint detection of the received signal and improve the overall error performance at the expense of an increased computational complexity. In this paper, the performance-complexity tradeoff of cooperative detection is investigated for uplink transmissions. Numerical results show that the cooperative detection gain may reach 10 dB at a Bit-Error Rate (BER) of 10 -2 when compared to the case without cooperation. © 2012 IEEE.

  14. Cooperative decoding in femtocell networks: Performance-complexity tradeoff

    KAUST Repository

    Benkhelifa, Fatma; Rezki, Zouheir; Alouini, Mohamed-Slim

    2012-01-01

    Femtocells, which are low cost low power, stand alone cellular access points, are a potential solution to provide good indoor coverage with high data rate. However, the femtocell deployment may also increase the co-channel interference (CCI) by reducing the distance reuse of the spectrum. In this paper, we introduce methods to cancel out the interference among the femtocells while considering that macrocells operate orthogonally to the femtocells. The femtocells may also cooperate through joint detection of the received signal and improve the overall error performance at the expense of an increased computational complexity. In this paper, the performance-complexity tradeoff of cooperative detection is investigated for uplink transmissions. Numerical results show that the cooperative detection gain may reach 10 dB at a Bit-Error Rate (BER) of 10 -2 when compared to the case without cooperation. © 2012 IEEE.

  15. Using An Adapter To Perform The Chalfant-Style Containment Vessel Periodic Maintenance Leak Rate Test

    International Nuclear Information System (INIS)

    Loftin, B.; Abramczyk, G.; Trapp, D.

    2011-01-01

    Recently the Packaging Technology and Pressurized Systems (PT and PS) organization at the Savannah River National Laboratory was asked to develop an adapter for performing the leak-rate test of a Chalfant-style containment vessel. The PT and PS organization collaborated with designers at the Department of Energy's Pantex Plant to develop the adapter currently in use for performing the leak-rate testing on the containment vessels. This paper will give the history of leak-rate testing of the Chalfant-style containment vessels, discuss the design concept for the adapter, give an overview of the design, and will present results of the testing done using the adapter.

  16. Fast photon detection for the COMPASS RICH detector

    CERN Document Server

    Abbon, P; Alekseev, M; Angerer, H; Apollonio, M; Birsa, R; Bordalo, P; Bradamante, Franco; Bressan, A; Busso, L; Chiosso, M; Ciliberti, P; Colantoni, M L; Costa, S; Dalla Torre, S; Dafni, T; Delagnes, E; Deschamps, H; Díaz, V; Dibiase, N; Duic, V; Eyrich, W; Faso, D; Ferrero, A; Finger, M; Finger, M Jr; Fischer, H; Gerassimov, S; Giorgi, M; Gobbo, B; Hagemann, R; Von Harrach, D; Heinsius, F H; Joosten, R; Ketzer, B; Königsmann, K C; Kolosov, V N; Konorov, I; Kramer, Daniel; Kunne, Fabienne; Lehmann, A; Levorato, S; Maggiora, A; Magnon, A; Mann, A; Martin, A; Menon, G; Mutter, A; Nahle, O; Nerling, F; Neyret, D; Pagano, P; Panebianco, S; Panzieri, D; Paul, S; Pesaro, G; Polak, J; Rebourgeard, P; Robinet, F; Rocco, E; Schiavon, Paolo; Schroder, W; Silva, L; Slunecka, M; Sozzi, F; Steiger, L; Sulc, M; Svec, M; Tessarotto, F; Teufel, A; Wollny, H

    2007-01-01

    The COMPASS experiment at the SPS accelerator at CERN uses a large scale Ring Imaging CHerenkov detector (RICH) to identify pions, kaons and protons in a wide momentum range. For the data taking in 2006, the COMPASS RICH has been upgraded in the central photon detection area (25% of the surface) with a new technology to detect Cherenkov photons at very high count rates of several 10^6 per second and channel and a new dead-time free read-out system, which allows trigger rates up to 100 kHz. The Cherenkov photons are detected by an array of 576 visible and ultra-violet sensitive multi-anode photomultipliers with 16 channels each. The upgraded detector showed an excellent performance during the 2006 data taking.

  17. On the performance of joint iterative detection and decoding in coherent optical channels with laser frequency fluctuations

    Science.gov (United States)

    Castrillón, Mario A.; Morero, Damián A.; Agazzi, Oscar E.; Hueda, Mario R.

    2015-08-01

    The joint iterative detection and decoding (JIDD) technique has been proposed by Barbieri et al. (2007) with the objective of compensating the time-varying phase noise and constant frequency offset experienced in satellite communication systems. The application of JIDD to optical coherent receivers in the presence of laser frequency fluctuations has not been reported in prior literature. Laser frequency fluctuations are caused by mechanical vibrations, power supply noise, and other mechanisms. They significantly degrade the performance of the carrier phase estimator in high-speed intradyne coherent optical receivers. This work investigates the performance of the JIDD algorithm in multi-gigabit optical coherent receivers. We present simulation results of bit error rate (BER) for non-differential polarization division multiplexing (PDM)-16QAM modulation in a 200 Gb/s coherent optical system that includes an LDPC code with 20% overhead and net coding gain of 11.3 dB at BER = 10-15. Our study shows that JIDD with a pilot rate ⩽ 5 % compensates for both laser phase noise and laser frequency fluctuation. Furthermore, since JIDD is used with non-differential modulation formats, we find that gains in excess of 1 dB can be achieved over existing solutions based on an explicit carrier phase estimator with differential modulation. The impact of the fiber nonlinearities in dense wavelength division multiplexing (DWDM) systems is also investigated. Our results demonstrate that JIDD is an excellent candidate for application in next generation high-speed optical coherent receivers.

  18. Factor-Based Student Rating in Academic Performance in Southern Province of Rwanda

    Science.gov (United States)

    Rulinda, Ephrard; Role, Elizabeth; Makewa, Lazarus Ndiku

    2013-01-01

    This study examined students' perception on academic performance using five-factor ratings namely, principal's instructional leadership, school climate, school facilities, teachers' effectiveness and family support. Data for this study were collected from selected Parent's Private Seventh-Day Adventist Secondary Schools (PPSDASS) in Southern…

  19. Automatic Atrial Fibrillation Detection: A Novel Approach Using Discrete Wavelet Transform and Heart Rate Variabilit

    DEFF Research Database (Denmark)

    Bruun, Iben H.; Hissabu, Semira M. S.; Poulsen, Erik S.

    2017-01-01

    be used as a screening tool for patients suspected to have AF. The method includes an automatic peak detection prior to the feature extraction, as well as a noise cancellation technique followed by a bagged tree classification. Simulation studies on the MIT-BIH Atrial Fibrillation database was performed...

  20. False discovery rate control incorporating phylogenetic tree increases detection power in microbiome-wide multiple testing.

    Science.gov (United States)

    Xiao, Jian; Cao, Hongyuan; Chen, Jun

    2017-09-15

    Next generation sequencing technologies have enabled the study of the human microbiome through direct sequencing of microbial DNA, resulting in an enormous amount of microbiome sequencing data. One unique characteristic of microbiome data is the phylogenetic tree that relates all the bacterial species. Closely related bacterial species have a tendency to exhibit a similar relationship with the environment or disease. Thus, incorporating the phylogenetic tree information can potentially improve the detection power for microbiome-wide association studies, where hundreds or thousands of tests are conducted simultaneously to identify bacterial species associated with a phenotype of interest. Despite much progress in multiple testing procedures such as false discovery rate (FDR) control, methods that take into account the phylogenetic tree are largely limited. We propose a new FDR control procedure that incorporates the prior structure information and apply it to microbiome data. The proposed procedure is based on a hierarchical model, where a structure-based prior distribution is designed to utilize the phylogenetic tree. By borrowing information from neighboring bacterial species, we are able to improve the statistical power of detecting associated bacterial species while controlling the FDR at desired levels. When the phylogenetic tree is mis-specified or non-informative, our procedure achieves a similar power as traditional procedures that do not take into account the tree structure. We demonstrate the performance of our method through extensive simulations and real microbiome datasets. We identified far more alcohol-drinking associated bacterial species than traditional methods. R package StructFDR is available from CRAN. chen.jun2@mayo.edu. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com