WorldWideScience

Sample records for mode method detection

  1. Gearbox Typical Failure Modes, Detection, and Mitigation Methods (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, S.

    2014-01-01

    This presentation was given at the AWEA Operations & Maintenance and Safety Seminar and focused on what the typical gearbox failure modes are, how to detect them using detection techniques, and strategies that help mitigate these failures.

  2. Comparison of multi-mode parallel detection microscopy methods

    Science.gov (United States)

    Zhu, Dazhao; Fang, Yue; Chen, Youhua; Hussain, Anwar; Kuang, Cuifang; Ding, Zhihua; Liu, Xu

    2017-03-01

    Four microscopy resolution enhancement methods based on parallel detection were investigated in this study: confocal microscopy with four pinhole sizes, fluorescence emission difference microscopy (FED) based on parallel detection, Airyscan microscopy, and virtual k-vector modulation optical microscopy (Vikmom). These methods use different algorithms to process parallel detection data and achieve resolution improvement. We investigated these methods first by performing simulations and then experimentally. In this report, the basic theories of these methods are briefly introduced. Then, analyses and comparisons of their imaging performances, especially in terms of resolution improvement, imaging speed, and signal-to-noise ratio, are presented. Finally, the results of our comparative study are summarized.

  3. Does mode mixing matter in EMD-based highlight volume methods for hydrocarbon detection? Experimental evidence

    Science.gov (United States)

    Xue, Ya-juan; Cao, Jun-xing; Du, Hao-kun; Zhang, Gu-lan; Yao, Yao

    2016-09-01

    Empirical mode decomposition (EMD)-based spectral decomposition methods have been successfully used for hydrocarbon detection. However, mode mixing that occurs during the sifting process of EMD causes the 'true' intrinsic mode function (IMF) to be extracted incorrectly and blurs the physical meaning of the IMF. We address the issue of how the mode mixing influences the EMD-based methods for hydrocarbon detection by introducing mode-mixing elimination methods, specifically ensemble EMD (EEMD) and complete ensemble EMD (CEEMD)-based highlight volumes, as feasible tools that can identify the peak amplitude above average volume and the peak frequency volume. Three schemes, that is, using all IMFs, selected IMFs or weighted IMFs, are employed in the EMD-, EEMD- and CEEMD-based highlight volume methods. When these methods were applied to seismic data from a tight sandstone gas field in Central Sichuan, China, the results demonstrated that the amplitude anomaly in the peak amplitude above average volume captured by EMD, EEMD and CEEMD combined with Hilbert transforms, whether using all IMFs, selected IMFs or weighted IMFs, are almost identical to each other. However, clear distinctions can be found in the peak frequency volume when comparing results generated using all IMFs, selected IMFs, or weighted IMFs. If all IMFs are used, the influence of mode mixing on the peak frequency volume is not readily discernable. However, using selected IMFs or a weighted IMFs' scheme affects the peak frequency in relation to the reservoir thickness in the EMD-based method. Significant improvement in the peak frequency volume can be achieved in EEMD-based highlight volumes using selected IMFs. However, if the weighted IMFs' scheme is adopted (i.e., if the undesired IMFs are included with reduced weights rather than excluded from the analysis entirely), the CEEMD-based peak frequency volume provides a more accurate reservoir thickness estimate compared with the other two methods. This

  4. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Directory of Open Access Journals (Sweden)

    P. Vaattovaara

    2005-01-01

    Full Text Available New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm and the lower end of Aitken mode particles (d≤50 nm is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer method to shed light on the presence of an organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10 nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various oxidized organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  5. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Directory of Open Access Journals (Sweden)

    P. Vaattovaara

    2005-06-01

    Full Text Available New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm and the lower end of Aitken mode particles (d≤50 nm is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer method to shed light on the presence of organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  6. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Science.gov (United States)

    Vaattovaara, P.; Räsänen, M.; Kühn, T.; Joutsensaari, J.; Laaksonen, A.

    2005-12-01

    New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, dammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various oxidized organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  7. Hardware Assisted ROP Detection Mode (HARD Mode)

    Science.gov (United States)

    2013-08-01

    Distribution A. Cleared for public release; unlimited distribution. USAFA-CN-2013-457 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART...457 This report, "Hardware Assisted ROP Detection Mode (HARD Mode)" is presented as a competent treatment of the subj ect, worthy of publication. The...Technical 20120810-20121215 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART MICHAEL WINSTEAD MARTIN CARLISLE RODNEY LYKINS MICHAEL

  8. Development of a nucleotide sugar purification method using a mixed mode column & mass spectrometry detection.

    Science.gov (United States)

    Eastwood, Heather; Xia, Fang; Lo, Mei-Chu; Zhou, Jing; Jordan, John B; McCarter, John; Barnhart, Wesley W; Gahm, Kyung-Hyun

    2015-11-10

    Analysis of nucleotide sugars, nucleoside di- and triphosphates and sugar-phosphates is an essential step in the process of understanding enzymatic pathways. A facile and rapid separation method was developed to analyze these compounds present in an enzymatic reaction mixture utilized to produce nucleotide sugars. The Primesep SB column explored in this study utilizes hydrophobic interactions as well as electrostatic interactions with the phosphoric portion of the nucleotide sugars. Ammonium formate buffer was selected due to its compatibility with mass spectrometry. Negative ion mode mass spectrometry was adopted for detection of the sugar phosphate (fucose-1-phophate), as the compound is not amenable to UV detection. Various mobile phase conditions such as pH, buffer concentration and organic modifier were explored. The semi-preparative separation method was developed to prepare 30mg of the nucleotide sugar. (19)F NMR was utilized to determine purity of the purified fluorinated nucleotide sugar. The collected nucleotide sugar was found to be 99% pure.

  9. A Mode Detection Method Using the Azimuthal Directivity of a Turbofan Model

    Science.gov (United States)

    Thomas, R. H.; Farassat, F.; Clark, L. R.; Gerhold, C. H.; Kelly, J. J.; Becker, L. E.

    1999-01-01

    The azimuthal, far field directivity of a scale fan model was measured in high resolution. The model is a 12 inch diameter rotor with 16 blades followed by 40 stator vanes. The tests were conducted at the nominal 100% speed corresponding to a tip speed of 905 ft/sec. Measurement of the radiated sound field, forward of the fan, was made in an anechoic chamber with an inflow control device and a baffle separating the aft and forward radiated interaction noise. The acoustic field was surveyed with a circular hoop array of 16 microphones which was moved to 14 axial stations. At each axial station the hoop was rotated in half-degree increments to take 736 points in the azimuthal angle. In addition to sound pressure level, the phase angle relative to a reference microphone was measured at each point. The sound pressure level is shown to vary in patterns by 10-15 dB especially for the fundamental tone but also for the first and second harmonic. A far field mode detection method has been developed and used with the data which determines the modes generated by the fan and which then interact to form the azimuthal directivity.

  10. A method for detecting the presence of organic fraction in nucleation mode sized particles

    OpenAIRE

    Vaattovaara, P.; Räsänen, M.; Kühn, T.; Joutsensaari, J.; Laaksonen, A.

    2005-01-01

    International audience; New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d

  11. Determination of Optimal Imaging Mode for Ultrasonographic Detection of Subdermal Contraceptive Rods: Comparison of Spatial Compound, Conventional, and Tissue Harmonic Imaging Methods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Jin; Seo, Kyung; Song, Ho Taek; Park, Ah Young; Kim, Yaena; Yoon, Choon Sik [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Suh, Jin Suck; Kim, Ah Hyun [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ryu, Jeong Ah [Dept. of Radiology, Guri Hospital, Hanyang University College of Medicine, Guri (Korea, Republic of); Park, Jeong Seon [Dept. of Radiology, Hanyang University Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2012-09-15

    To determine which mode of ultrasonography (US), among the conventional, spatial compound, and tissue-harmonic methods, exhibits the best performance for the detection of Implanon with respect to generation of posterior acoustic shadowing (PAS). A total of 21 patients, referred for localization of impalpable Implanon, underwent US, using the three modes with default settings (i.e., wide focal zone). Representative transverse images of the rods, according to each mode for all patients, were obtained. The resulting 63 images were reviewed by four observers. The observers provided a confidence score for the presence of PAS, using a five-point scale ranging from 1 (definitely absent) to 5 (definitely present), with scores of 4 or 5 for PAS being considered as detection. The average scores of PAS, obtained from the three different modes for each observer, were compared using one-way repeated measure ANOVA. The detection rates were compared using a weighted least square method. Statistically, the tissue harmonic mode was significantly superior to the other two modes, when comparing the average scores of PAS for all observers (p < 0.00-1). The detection rate was also highest for the tissue harmonic mode (p < 0.001). Tissue harmonic mode in US appears to be the most suitable in detecting subdermal contraceptive implant rods.

  12. Determination of optimal imaging mode for ultrasonographic detection of subdermal contraceptive rods: comparison of spatial compound, conventional, and tissue harmonic imaging methods.

    Science.gov (United States)

    Kim, Sungjun; Seo, Kyung; Song, Ho-Taek; Suh, Jin-Suck; Yoon, Choon-Sik; Ryu, Jeong Ah; Park, Jeong Seon; Kim, Ah Hyun; Park, Ah Young; Kim, Yaena

    2012-01-01

    To determine which mode of ultrasonography (US), among the conventional, spatial compound, and tissue-harmonic methods, exhibits the best performance for the detection of Implanon® with respect to generation of posterior acoustic shadowing (PAS). A total of 21 patients, referred for localization of impalpable Implanon®, underwent US, using the three modes with default settings (i.e., wide focal zone). Representative transverse images of the rods, according to each mode for all patients, were obtained. The resulting 63 images were reviewed by four observers. The observers provided a confidence score for the presence of PAS, using a five-point scale ranging from 1 (definitely absent) to 5 (definitely present), with scores of 4 or 5 for PAS being considered as detection. The average scores of PAS, obtained from the three different modes for each observer, were compared using one-way repeated measure ANOVA. The detection rates were compared using a weighted least square method. Statistically, the tissue harmonic mode was significantly superior to the other two modes, when comparing the average scores of PAS for all observers (p tissue harmonic mode (p Tissue harmonic mode in uS appears to be the most suitable in detecting subdermal contraceptive implant rods.

  13. Method for direct detection of pitch angle scattering of energetic electrons caused by whistler mode chorus emissions

    Science.gov (United States)

    Kitahara, M.; Katoh, Y.

    2016-06-01

    The Wave-Particle Interaction Analyzer (WPIA), a new instrument proposed by Fukuhara et al. (2009), measures the relative phase angle between the wave magnetic field vector and the velocity vector of each particle and calculates the energy exchange from waves to particles. In this study, we expand its applicability by proposing a method of using the WPIA to directly detect pitch angle scattering of resonant particles by plasma waves by calculating the g values. The g value is defined as the accumulation value of the Lorentz force acting on each particle and indicates the lost momentum of waves. We apply the proposed method to the results of a one-dimensional electron hybrid simulation reproducing the generation of whistler mode chorus emissions around the magnetic equator. Using the wave and particle data obtained at fixed observation points assumed in the simulation system, we conduct a pseudo-observation of the simulation result using the WPIA and analyze the g values. Our analysis yielded significant values indicating the strong pitch angle scattering for electrons in the kinetic energy and pitch angle ranges satisfying the cyclotron resonance condition with the reproduced chorus emissions. The results of this study demonstrate that the proposed method enables us to directly and quantitatively identify the location at which pitch angle scattering occurs in the simulation system and that the method can be applied to the results of space-based observations by the forthcoming Exploration of energization and Radiation in Geospace (ERG) satellite.

  14. Selective Mode Excitation And Detection Of Micromachined Resonators

    NARCIS (Netherlands)

    Prak, Albert; Elwenspoek, Miko; Fluitman, Jan H.J

    1992-01-01

    Distributed mechanical systems such as micromachined resonant strain gages possess an infinite number of modes of vibration. Mostly, one is interested in only one or a few modes. A method is described with which only the desired modes are excited and detected. This is achieved by geometrically shapi

  15. Fault-weighted quantification method of fault detection coverage through fault mode and effect analysis in digital I&C systems

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jaehyun; Lee, Seung Jun, E-mail: sjlee420@unist.ac.kr; Jung, Wondea

    2017-05-15

    Highlights: • We developed the fault-weighted quantification method of fault detection coverage. • The method has been applied to specific digital reactor protection system. • The unavailability of the module had 20-times difference with the traditional method. • Several experimental tests will be effectively prioritized using this method. - Abstract: The one of the most outstanding features of a digital I&C system is the use of a fault-tolerant technique. With an awareness regarding the importance of thequantification of fault detection coverage of fault-tolerant techniques, several researches related to the fault injection method were developed and employed to quantify a fault detection coverage. In the fault injection method, each injected fault has a different importance because the frequency of realization of every injected fault is different. However, there have been no previous studies addressing the importance and weighting factor of each injected fault. In this work, a new method for allocating the weighting to each injected fault using the failure mode and effect analysis data was proposed. For application, the fault-weighted quantification method has also been applied to specific digital reactor protection system to quantify the fault detection coverage. One of the major findings in an application was that we may estimate the unavailability of the specific module in digital I&C systems about 20-times smaller than real value when we use a traditional method. The other finding was that we can also classify the importance of the experimental case. Therefore, this method is expected to not only suggest an accurate quantification procedure of fault-detection coverage by weighting the injected faults, but to also contribute to an effective fault injection experiment by sorting the importance of the failure categories.

  16. Comparison of two Bayesian methods to detect mode effects between paper-based and computerized adaptive assessments: a preliminary Monte Carlo study

    Directory of Open Access Journals (Sweden)

    Riley Barth B

    2012-08-01

    Full Text Available Abstract Background Computerized adaptive testing (CAT is being applied to health outcome measures developed as paper-and-pencil (P&P instruments. Differences in how respondents answer items administered by CAT vs. P&P can increase error in CAT-estimated measures if not identified and corrected. Method Two methods for detecting item-level mode effects are proposed using Bayesian estimation of posterior distributions of item parameters: (1 a modified robust Z (RZ test, and (2 95% credible intervals (CrI for the CAT-P&P difference in item difficulty. A simulation study was conducted under the following conditions: (1 data-generating model (one- vs. two-parameter IRT model; (2 moderate vs. large DIF sizes; (3 percentage of DIF items (10% vs. 30%, and (4 mean difference in θ estimates across modes of 0 vs. 1 logits. This resulted in a total of 16 conditions with 10 generated datasets per condition. Results Both methods evidenced good to excellent false positive control, with RZ providing better control of false positives and with slightly higher power for CrI, irrespective of measurement model. False positives increased when items were very easy to endorse and when there with mode differences in mean trait level. True positives were predicted by CAT item usage, absolute item difficulty and item discrimination. RZ outperformed CrI, due to better control of false positive DIF. Conclusions Whereas false positives were well controlled, particularly for RZ, power to detect DIF was suboptimal. Research is needed to examine the robustness of these methods under varying prior assumptions concerning the distribution of item and person parameters and when data fail to conform to prior assumptions. False identification of DIF when items were very easy to endorse is a problem warranting additional investigation.

  17. An Eavesdropping Detecting Approach Based on Mode-Mode Correlation

    Institute of Scientific and Technical Information of China (English)

    XIONG Jin; ZENG Gui-Hua; ZHOU Nan-Run

    2005-01-01

    @@ We find that second-order coherence as well as a Hanbury-Brown-Twiss intensity interferometer may provide an optimal approach for eavesdropping detection in the quantum key distribution based on two-mode squeezed'vacuum states. With this approach, eavesdropping can be easily detected without sacrificing extra secret bits as the test key. In addition, the efficiency of the quantum key distribution protocol is enhanced greatly.

  18. Interferometric detection of mode splitting for whispering gallery mode biosensors

    CERN Document Server

    Knittel, Joachim; Lee, Kwan H; Bowen, Warwick P

    2010-01-01

    Sensors based on whispering gallery mode resonators can detect single nanoparticles and even single molecules. Particles attaching to the resonator induce a doublet in the transmission spectrum which provides a self-referenced detection signal. However, in practice this spectral feature is often obscured by the width of the resonance line which hides the doublet structure. This happens particularly in liquid environments that reduce the effective Q factor of the resonator. In this paper we demonstrate an interferometric set-up that allows the direct detection of the hidden doublet and thus provides a pathway for developing practical sensor applications.

  19. Towards Indoor Transportation Mode Detection using Mobile Sensing

    DEFF Research Database (Denmark)

    Prentow, Thor Siiger; Blunck, Henrik; Kjærgaard, Mikkel Baun

    2015-01-01

    Transportation mode detection is a growing field of research, in which a variety of methods have been developed for detecting transportation modes foremost for outdoor travels. It has been employed in application areas such as public transportation, environmental footprint profiling, and context......-aware mobile assistants. For indoor travels the problem of transportation mode detection has received comparatively little attention, even though diverse transportation modes, such as biking, electric vehicles, and scooters, are used indoors, especially in large building complexes. The potential applications...... are diverse, may also extend beyond indoor variants of the above outdoor applications, and include, e.g., scheduling and progress tracking for mobile workers, management of vehicular resources, and navigation support. However, for indoor transportation mode detection, both the physical environment as well...

  20. Real-time Detection of Locked Modes

    Science.gov (United States)

    Angelini, S.; Granetz, R. S.; Wolfe, S. M.

    2007-11-01

    Disruptions are one of the largest problems facing tokamaks. In a large-scale experiment such as ITER, disruptions would cause crippling damage and severe setbacks in experimentation. One method for disruption mitigation involves the use of a gas jet which has been tested on both normally running plasmas and vertical displacement events (VDEs) on Alcator C-Mod. In both cases, the jet was successful in mitigating disruption effects. The gas jet has not yet been tested on other types of disruptions. Locked-mode major disruptions are easily created in C-Mod and could be used to test the effectiveness of the gas jet as a mitigation method if the jet could be fired early enough. It has been empirically observed that the electron cyclotron emissions (ECE) signal displays a flattening of the normally-present sawteeth before the current quench occurs in certain locked-mode major disruptions. A procedure is being written which will detect the ECE flattening by reading changes in the standard deviation of the signal. This procedure will be programmed into the digital plasma control system (DPCS) for real-time testing.

  1. Detecting solar g-modes with ASTROD

    CERN Document Server

    Burston, R; Appourchaux, T; Ni, W T

    2008-01-01

    We present an up-to-date estimate for the prospect of using the Astrodynamical Space Test of Relativity using Optical Devices (ASTROD) for an unambiguous detection of solar g modes (f < 400 micro Hertz) through their gravitational signature. There are currently two major efforts to detect low-frequency gravitational effects, ASTROD and the Laser Interferometer Space Antenna (LISA). Using the most recent g mode surface amplitude estimates, both observational and theoretical, it is unclear whether LISA will be capable of successfully detecting these modes. The ASTROD project may be better suited for detection as its sensitivity curve is shifted towards lower frequencies with the best sensitivity occurring in the range 100-300 micro Hertz.

  2. Selective Detection and Automated Counting of Fluorescently-Labeled Chrysotile Asbestos Using a Dual-Mode High-Throughput Microscopy (DM-HTM Method

    Directory of Open Access Journals (Sweden)

    Jung Kyung Kim

    2013-05-01

    Full Text Available Phase contrast microscopy (PCM is a widely used analytical method for airborne asbestos, but it is unable to distinguish asbestos from non-asbestos fibers and requires time-consuming and laborious manual counting of fibers. Previously, we developed a high-throughput microscopy (HTM method that could greatly reduce human intervention and analysis time through automated image acquisition and counting of fibers. In this study, we designed a dual-mode HTM (DM-HTM device for the combined reflection and fluorescence imaging of asbestos, and automated a series of built-in image processing commands of ImageJ software to test its capabilities. We used DksA, a chrysotile-adhesive protein, for selective detection of chrysotile fibers in the mixed dust-free suspension of crysotile and amosite prepared in the laboratory. We demonstrate that fluorescently-stained chrysotile and total fibers can be identified and enumerated automatically in a high-throughput manner by the DM-HTM system. Combined with more advanced software that can correctly identify overlapping and branching fibers and distinguish between fibers and elongated dust particles, the DM-HTM method should enable fully automated counting of airborne asbestos.

  3. Review of Transportation Mode Detection techniques

    Directory of Open Access Journals (Sweden)

    Jacopo Biancat

    2014-10-01

    Full Text Available This paper reviews the works found in the literature in the field of Transportation Mode Detection (TMD which is a subfield of Activity Recognition aiming at indentifying (i.e. classifying the mean of transportation a person is using. The solutions found in literature have different characteristics according to the device for which the solution was tailored (smartphones or other systems such as, e.g., GPS loggers and to the algorithm used for the classification task. This may vary a lot according to the number and type of input used (e.g. accelerations, GPS, maps information or GIS - Geographical Information System information and to the identified classes of transportation mode. These two aspects are the most relevant to consider when evaluating and comparing the accuracies claimed by each work. A comparison of the works is proposed taking into account the characteristics discussed above. In general the accelerometer is the most widely used sensor for TMD applications, as it limits battery consumption and captures relevant features for detecting motion. Indeed a key challenge in TMD is to detect different motorized classes such as bus, car, train and metro because they share common characteristics (such as e.g. the average speed and accelerations which make hard identifying suitable features for the classification algorithm. Identifying the “walk” and “stationary” transportation modes is a simpler task because they are characterized by distinct features.

  4. Railway Wheel Flat Detection Based on Improved Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Yifan Li

    2016-01-01

    Full Text Available This study explores the capacity of the improved empirical mode decomposition (EMD in railway wheel flat detection. Aiming at the mode mixing problem of EMD, an EMD energy conservation theory and an intrinsic mode function (IMF superposition theory are presented and derived, respectively. Based on the above two theories, an improved EMD method is further proposed. The advantage of the improved EMD is evaluated by a simulated vibration signal. Then this method is applied to study the axle box vibration response caused by wheel flats, considering the influence of both track irregularity and vehicle running speed on diagnosis results. Finally, the effectiveness of the proposed method is verified by a test rig experiment. Research results demonstrate that the improved EMD can inhibit mode mixing phenomenon and extract the wheel fault characteristic effectively.

  5. PRECISELY COMPENSATED EFFICIENT COMPONENT MODE SYNTHESIS METHOD

    Institute of Scientific and Technical Information of China (English)

    Zhu Yutian; Ichiro Hagiwara

    2004-01-01

    Based on the improved mode superposition method proposed by Z.D.Ma and I.Hagiwara, a precisely compensated efficient mode synthesis method is developed.The calculation procedure is discussed in detail and the truncation error is also analyzed.By comparison, it is shown that this method has a higher accuracy and a less calculation time than the general used ones.

  6. Photon detection efficiency of Geiger-mode avalanche photodiodes

    OpenAIRE

    Gentile, Simonetta; Kuznetsova, Ekaterina; Meddi, Franco

    2010-01-01

    The photon detection efficiencies of multi-pixel Geiger-mode avalanche photodiodes manufactured by different produ cers are estimated. A new fit method of the response spectra to low-intensity light, taking into ac count after-pulse and cross-talk effects is proposed to yield the initial number of photons. The value of photon detection efficiency is calculated using a calibrated photodetector as a reference.

  7. Whispering Gallery Mode Microresonators for Lasing and Single Nanoparticle Detection

    Science.gov (United States)

    He, Lina

    Whispering gallery mode (WGM) microresonators have attracted great interests due to the significantly enhanced light-matter interactions originating from their high quality factors and small mode volumes. They are suitable for a wide range of applications including sensing, lasing, nonlinear optics, and so forth. However, temperature fluctuations as one of the most common environmental noises disturb the cavity resonances and thus degrade the device stability and sensitivity. We introduce a wetting technique to coat the silica resonator with a thin layer of polymer which has the negative thermo-optic coefficient to compensate for the thermal effect in silica, and demonstrate complete thermal compensation. WGM microresonators have shown great promise for ultra-sensitive and label-free chemical and biological sensing by probing the surroundings with evanescent waves leaking out of the resonator. Sensing is achieved by monitoring the shift or splitting of a resonant frequency. The detection limit is determined by the linewidth of the resonant mode which is ultimately limited by material absorption induced loss. To surpass the limit of passive resonators, we report real-time single nanoparticle detection using on-chip WGM microcavity lasers. The ultra-low threshold microlasers are prepared by doping WGM resonators with rare-earth ions through the sol-gel method, and their linewidths are much narrower than the passive counterparts. The detection approach relies on measuring changes in the heterodyne beat note of two split modes originating from splitting of a narrow emission line in the microlaser induced by nanoscale objects. We demonstrate detection of polystyrene and gold nanoparticles as small as 15 nm and 10 nm in radius, respectively, and Influenza A virions by monitoring changes in the beat note of the split lasing modes. The self-heterodyne interferometric method achieved in the on-chip microlaser provides a self-referencing scheme with extraordinary sensitivity

  8. Travel Mode Detection Exploiting Cellular Network Data

    Directory of Open Access Journals (Sweden)

    Kalatian Arash

    2016-01-01

    Full Text Available There has been growing interest in exploiting cellular network data for transportation planning purposes in recent years. In this paper, we utilize these data for determining mode of travel in the city of Shiraz, Iran. Cellular data records -including location updates in 5minute time intervals- of 300,000 users from the city of Shiraz has been collected for 40 hours in three consecutive days in a cooperation with the major telecommunications service provider of the country. Depending on the density of mobile BTS’s in different zones of the city, the user location can be located within an average of 200 meters. Considering data filtering and smoothing, data preparation and converting them to comprehensible traces is a large portion of the work. A novel approach to identify stay locations is proposed and implemented in this paper. Origin-Destination matrices are then created based on trips detected, which shows acceptable consistency with current O-D matrices. Finally, Travel times for all trips of a user is estimated as the main attribute for clustering. Trips between same origin and destination zones are combined together in a group. Using K-means algorithm, records within each group are the portioned in two or three clusters, based on their travel speeds. Each cluster represents a certain mode of travel; walking, public transportation or driving a private car.

  9. Detecting mode hopping in single-longitudinal-mode fiber ring lasers based on an unbalanced fiber Michelson interferometer.

    Science.gov (United States)

    Ma, Mingxiang; Hu, Zhengliang; Xu, Pan; Wang, Wei; Hu, Yongming

    2012-10-20

    A method of detecting mode hopping for single-longitudinal-mode (SLM) fiber ring lasers has been proposed and experimentally demonstrated. The method that is based on an unbalanced Michelson interferometer (MI) utilizing phase generated carrier modulation instantly transforms mode-hopping dynamics into steep phase changes of the interferometer. Multiform mode hops in an SLM erbium-doped fiber ring laser with an 18.6 MHz mode spacing have been detected exactly in real-time domain and discussed in detail. Numerical results show that the MI-based method has a high testing sensitivity for identifying mode hopping, which will play a significant role in evaluating the output stability of SLM fiber lasers.

  10. Soybean allergen detection methods

    DEFF Research Database (Denmark)

    Pedersen, Mona H; Holzhauser, Thomas; Bisson, Caroline

    2008-01-01

    Soybean containing products are widely consumed, thus reliable methods for detection of soy in foods are needed in order to make appropriate risk assessment studies to adequately protect soy allergic patients. Six methods were compared using eight food products with a declared content of soy...

  11. Eigenvalue translation method for mode calculations.

    Science.gov (United States)

    Gerck, E; Cruz, C H

    1979-05-01

    A new method is described for the first few modes calculations in a interferometer that has several advantages over the Allmat subroutine, the Prony method, and the Fox and Li method. In the illustrative results shown for some cases it can be seen that the eigenvalue translation method is typically 100-fold times faster than the usual Fox and Li method and ten times faster than Allmat.

  12. Exoplanet Detection Methods

    CERN Document Server

    Wright, Jason T

    2012-01-01

    This chapter reviews various methods of detecting planetary companions to stars from an observational perspective, focusing on radial velocities, astrometry, direct imaging, transits, and gravitational microlensing. For each method, this chapter first derives or summarizes the basic observable phenomena that are used to infer the ex- istence of planetary companions, as well as the physical properties of the planets and host stars that can be derived from the measurement of these signals. This chapter then outlines the general experimental requirements to robustly detect the signals us- ing each method, by comparing their magnitude to the typical sources of measurement uncertainty. This chapter goes on to compare the various methods to each other by outlining the regions of planet and host star parameter space where each method is most sensitive, stressing the complementarity of the ensemble of the methods at our disposal. Finally, there is a brief review of the history of the young exoplanet field, from the f...

  13. Methods of Endotoxin Detection.

    Science.gov (United States)

    Su, Wenqiong; Ding, Xianting

    2015-08-01

    Endotoxin, present in the outer membrane of all gram-negative bacteria, can pose serious risks to human health, from irreversible shock to death. Therefore, it is essential to develop sensitive, accurate, and rapid methods for its detection. The rabbit pyrogen test is the first standard technique for endotoxin detection and, nowadays, has been replaced by the Limulus Amoebocyte Lysate test, which is the most popular detection technique for endotoxin. With in-depth understanding of endotoxin, biosensors based on endotoxin-sensing components are promising alternatives to pursue in developing low-cost, easy-operation, and fast-response endotoxin detection techniques. This article summarizes the recent advances of endotoxin detection methods with a particular emphasis on optical and electrochemical biosensors based on various sensing elements ranging from nature biomolecules to artificial materials. As the research and technological revolution continues, the highly integrated and miniaturized commercial devices for sensitively and reliably detecting endotoxin will provide a wide range of applications in people's daily life.

  14. Transportation mode detection by using smartphone sensors and machine learning

    Directory of Open Access Journals (Sweden)

    Ensar Arif Sağbaş

    2016-10-01

    Full Text Available The aim of this study is to detect transportation modes of the users by using smartphone sensors. Therefore, GPS (Global Positioning System, accelerometer and gyroscope sensor data have been collected while walking, running, cycling and travelling by bus or by car from the smartphone of the user. Sensor data were tagged with 12 second interval and 2500 pattern were obtained. 14 features were acquired from the dataset. Machine learning methods were tested on the dataset. Best result was obtained from GPS, accelerometer and gyroscope sensor combination and Random Forest method with 99.4% accuracy rate.

  15. Method for detecting biomolecules

    Science.gov (United States)

    Huo, Qisheng; Liu, Jun

    2008-08-12

    A method for detecting and measuring the concentration of biomolecules in solution, utilizing a conducting electrode in contact with a solution containing target biomolecules, with a film with controllable pore size distribution characteristics applied to at least one surface of the conducting electrode. The film is functionalized with probe molecules that chemically interact with the target biomolecules at the film surface, blocking indicator molecules present in solution from diffusing from the solution to the electrode, thereby changing the electrochemical response of the electrode

  16. Optimization of two methods for the analysis of hydrogen peroxide: high performance liquid chromatography with fluorescence detection and high performance liquid chromatography with electrochemical detection in direct current mode.

    Science.gov (United States)

    Tarvin, Megan; McCord, Bruce; Mount, Kelly; Sherlach, Katy; Miller, Mark L

    2010-11-26

    Two complementary methods were optimized for the separation and detection of trace levels of hydrogen peroxide. The first method utilized reversed-phase high-performance liquid chromatography with fluorescence detection (HPLC-FD). With this approach, hydrogen peroxide was detected based upon its participation in the hemin-catalyzed oxidation of p-hydroxyphenylacetic acid to yield the fluorescent dimer. The second method utilized high performance liquid chromatography with electrochemical detection (HPLC-ED). With this approach, hydrogen peroxide was detected based upon its oxidation at a gold working electrode at an applied potential of 400 mV vs. hydrogen reference electrode (Pd/H(2)). Both methods were linear across the range of 15-300 μM, and the electrochemical method was linear across a wider range of 7.4-15,000 μM. The limit of detection for hydrogen peroxide was 6 μM by HPLC/FD, and 0.6 μM by HPLC/ED. A series of organic peroxides and inorganic ions were evaluated for their potential to interfere with the detection of hydrogen peroxide. Studies investigating the recovery of hydrogen peroxide with three different extraction protocols were also performed. Post-blast debris from the detonation of a mixture of concentrated hydrogen peroxide with nitromethane was analyzed on both systems. Hydrogen peroxide residues were successfully detected on this post-blast debris.

  17. Geiger-Mode Avalanche Photodiodes in Particle Detection

    OpenAIRE

    Vilella, E.; Alonso, O.; Trenado, J.; Vilà, A.; De Vos, M.; Garrido, L.; Diéguez, A.

    2012-01-01

    It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite sensitivity and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection remains still unexplored. In this contribution, we are going to expose the different steps that we have taken in order to prove the efficiency of Geiger mode avalanche photodiodes in the aforementioned field. In particula...

  18. Prospects for Inflationary B-Mode Detection

    Science.gov (United States)

    Kogut, Alan J.

    2011-01-01

    Measurements of the linear polarization of the cosmic microwave background provide a direct window into the physics of inflation. The experimental challenges are daunting: not only is the predicted signal faint compared to the photon noise limit, but it is hidden behind competing foregrounds from both local and cosmic sources. I will discuss the experimental response to these challenges and the prospects for eventual detection and characterization of the inflationary signal.

  19. Delamination detection in composite laminates using dispersion change based on mode conversion of Lamb waves

    Science.gov (United States)

    Okabe, Yoji; Fujibayashi, Keiji; Shimazaki, Mamoru; Soejima, Hideki; Ogisu, Toshimichi

    2010-11-01

    A new ultrasonic propagation system has been constructed using macrofiber composite (MFC) actuators and fiber Bragg grating (FBG) sensors. The MFCs and FBGs can be integrated into composite laminates because of their small size and high fracture strain. The developed system can send and receive broadband Lamb waves. In this research, this system was used to detect delamination damage in composite laminates. First, the multiple modes of Lamb waves in a carbon-fiber-reinforced plastic (CFRP) quasi-isotropic laminate were identified by transmitting and receiving the symmetric and antisymmetric modes separately. Then, the mode conversions at both tips of a delamination were investigated through an experiment and a two-dimensional finite element analysis (FEA). A new delamination detection method was proposed on the basis of the mode conversions, and experiments were carried out on laminates with an artificial delamination. When antisymmetric modes were excited, the frequency dispersion of the received A1 mode changed, depending on the delamination length owing to the mode conversion between the A1 mode and the S0 mode. This phenomenon was confirmed through the FEA and these results prove that this new method is effective in detecting a delamination in CFRP laminates.

  20. Modular Detection System for Special Nuclear Material (MODES_SNM)

    Science.gov (United States)

    Christodoulou, Georgios

    2014-02-01

    The MODES_SNM project, funded by the European Community within the scope of the FP7 security theme, explores new techniques for the design and demonstration of novel technologies for the detection of dangerous radioactive materials. Noble gas pressurized detectors are developed and optimized to build a human portable modular detector system to detect and identify illicit SNM. Since masked or shielded SNM is hard to detect, the MODES_SNM detector system will be sensitive to both fast and thermal neutrons and to photons emitted by the SNM. Thus, the project aims to increase the detection sensitivity of shielded SNM, to reduce the false alarm rate and to provide a mobile system to be used by both experts and non-experts in the field of radiation detection. The project now enters into its final phase towards the construction and characterization of a working prototype to be tested under laboratory conditions and in a real world environment.

  1. Nonlinear Multiantenna Detection Methods

    Directory of Open Access Journals (Sweden)

    Chen Sheng

    2004-01-01

    Full Text Available A nonlinear detection technique designed for multiple-antenna assisted receivers employed in space-division multiple-access systems is investigated. We derive the optimal solution of the nonlinear spatial-processing assisted receiver for binary phase shift keying signalling, which we refer to as the Bayesian detector. It is shown that this optimal Bayesian receiver significantly outperforms the standard linear beamforming assisted receiver in terms of a reduced bit error rate, at the expense of an increased complexity, while the achievable system capacity is substantially enhanced with the advent of employing nonlinear detection. Specifically, when the spatial separation expressed in terms of the angle of arrival between the desired and interfering signals is below a certain threshold, a linear beamformer would fail to separate them, while a nonlinear detection assisted receiver is still capable of performing adequately. The adaptive implementation of the optimal Bayesian detector can be realized using a radial basis function network. Two techniques are presented for constructing block-data-based adaptive nonlinear multiple-antenna assisted receivers. One of them is based on the relevance vector machine invoked for classification, while the other on the orthogonal forward selection procedure combined with the Fisher ratio class-separability measure. A recursive sample-by-sample adaptation procedure is also proposed for training nonlinear detectors based on an amalgam of enhanced -means clustering techniques and the recursive least squares algorithm.

  2. NOLB : Non-linear rigid block normal mode analysis method.

    Science.gov (United States)

    Hoffmann, Alexandre; Grudinin, Sergei

    2017-04-05

    We present a new conceptually simple and computationally efficient method for non-linear normal mode analysis called NOLB. It relies on the rotations-translations of blocks (RTB) theoretical basis developed by Y.-H. Sanejouand and colleagues. We demonstrate how to physically interpret the eigenvalues computed in the RTB basis in terms of angular and linear velocities applied to the rigid blocks and how to construct a non-linear extrapolation of motion out of these velocities. The key observation of our method is that the angular velocity of a rigid block can be interpreted as the result of an implicit force, such that the motion of the rigid block can be considered as a pure rotation about a certain center. We demonstrate the motions produced with the NOLB method on three different molecular systems and show that some of the lowest frequency normal modes correspond to the biologically relevant motions. For example, NOLB detects the spiral sliding motion of the TALE protein, which is capable of rapid diffusion along its target DNA. Overall, our method produces better structures compared to the standard approach, especially at large deformation amplitudes, as we demonstrate by visual inspection, energy and topology analyses, and also by the MolProbity service validation. Finally, our method is scalable and can be applied to very large molecular systems, such as ribosomes. Standalone executables of the NOLB normal mode analysis method are available at https://team.inria.fr/nano-d/software/nolb-normal-modes. A graphical user interfaces created for the SAMSON software platform will be made available at https: //www.samson-connect.net.

  3. Detection limits in plasmonic whispering gallery mode biosensors

    CERN Document Server

    Swaim, Jon D; Bowen, Warwick P

    2011-01-01

    We analyze a whispering gallery mode biosensor with a metallic nanorod bound to its surface. It is found that a localized surface plasmon resonance in the nanorod can reduce the optical mode volume of the resonator by as much as four orders of magnitude via a local enhancement of the electric field, thus improving the detection sensitivity. Optical frequency shifts as large as 15 MHz are predicted for typical proteins and, for typical experimental parameters, the biosensor is predicted to be limited by laser frequency noise, leading to a minimum detectable polarizability on the order of 10 cubic angstroms.

  4. Geiger-Mode Avalanche Photodiodes in Particle Detection

    CERN Document Server

    Vilella, E; Trenado, J; Vila, A; Vos, M; Garrido, L; Dieguez, A

    2012-01-01

    It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite sensitivity and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection remains still unexplored. In this contribution, we are going to expose the different steps that we have taken in order to prove the efficiency of Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present an array of pixels of 1mmx1mm fabricated with a standard CMOS technology for characterization in a test beam.

  5. 基于应变模态变化率的钢轨损伤检测%Detection Method for Broken Rail Based on Rate of Change of Strain Mode

    Institute of Scientific and Technical Information of China (English)

    赵才友; 王平; 全顺喜; 曹洋; 胡国祥

    2012-01-01

    In order to quickly and accurately detect the rail damage and the position and extent of damage, a new rail damage detection method which is based on the rate of change of strain mode is put forward. Taking five cross rail as an example, through the numerical simulation analysis and laboratory model test, the results show that: Based on the frequency change, it can determine the rail damage occurs, but is unable to determine the location and extent of damage; based on strain modal changes, it can determine the rail damage, the location and extent of injury; based on strain modal changes in the rate of change, it can determine the rail damage, the location and extent of injury; injury severity influences damage identification greatly. Injury severity is greater, the rate of change of strain mode of the injuried element is bigger. The two order strain mode change rate of the rail can determine injury occurrence, damage location and damage degree.%为了准确、快速检测出钢轨中的损伤及其损伤位置和程度,提出了基于应变模态变化率的钢轨损伤检测方法.以五跨钢轨为例,通过数值仿真分析和实验室足尺模型测试表明:基于频率的变化可判断钢轨发生损伤,但无法确定损伤的位置及程度;基于应变模态的变化和基于应变模态变化率的变化可判断钢轨发生损伤、确定损伤的位置和程度;损伤程度对于损伤识别的影响较大,损伤程度越大,损伤单元的应变模态变化率就越大,钢轨的前两阶应变模态变化率可以确定损伤的发生、位置及损伤程度.

  6. Detecting individual gravity modes in the Sun: Chimera or reality?

    CERN Document Server

    Garcia, Rafael A; Eff-Darwich, A; Garrido, R; Jimenez, A; Mathis, S; Mathur, S; Moya, A; Palle, P L; Regulo, C; Salabert, D; Sato, K; Suarez, J C; Turck-Chieze, S

    2009-01-01

    Over the past 15 years, our knowledge of the interior of the Sun has tremendously progressed by the use of helioseismic measurements. However, to go further in our understanding of the solar core, we need to measure gravity (g) modes. Thanks to the high quality of the Doppler-velocity signal measured by GOLF/SoHO, it has been possible to unveil the signature of the asymptotic properties of the solar g modes, thus obtaining a hint of the rotation rate in the core. However, the quest for the detection of individual g modes is not yet over. In this work, we apply the latest theoretical developments to guide our research using GOLF velocity time series. In contrary to what was thought till now, we are maybe starting to identify individual low-frequency g modes...

  7. A Voltage Quality Detection Method

    DEFF Research Database (Denmark)

    Chen, Zhe; Wei, Mu

    2008-01-01

    This paper presents a voltage quality detection method based on a phase-locked loop (PLL) technique. The technique can detect the voltage magnitude and phase angle of each individual phase under both normal and fault power system conditions. The proposed method has the potential to evaluate vario...... power quality disturbances, such as interruptions, sags and imbalances. Simulation studies have been performed. The effectiveness of the proposed method has been demonstrated under the simulated typical power disturbances....

  8. Local method for detecting communities

    Science.gov (United States)

    Bagrow, James P.; Bollt, Erik M.

    2005-10-01

    We propose a method of community detection that is computationally inexpensive and possesses physical significance to a member of a social network. This method is unlike many divisive and agglomerative techniques and is local in the sense that a community can be detected within a network without requiring knowledge of the entire network. A global application of this method is also introduced. Several artificial and real-world networks, including the famous Zachary karate club, are analyzed.

  9. Reason and Condition for Mode Kissing in MASW Method

    Science.gov (United States)

    Gao, Lingli; Xia, Jianghai; Pan, Yudi; Xu, Yixian

    2016-05-01

    Identifying correct modes of surface waves and picking accurate phase velocities are critical for obtaining an accurate S-wave velocity in MASW method. In most cases, inversion is easily conducted by picking the dispersion curves corresponding to different surface-wave modes individually. Neighboring surface-wave modes, however, will nearly meet (kiss) at some frequencies for some models. Around the frequencies, they have very close roots and energy peak shifts from one mode to another. At current dispersion image resolution, it is difficult to distinguish different modes when mode-kissing occurs, which is commonly seen in near-surface earth models. It will cause mode misidentification, and as a result, lead to a larger overestimation of S-wave velocity and error on depth. We newly defined two mode types based on the characteristics of the vertical eigendisplacements calculated by generalized reflection and transmission coefficient method. Rayleigh-wave mode near the kissing points (osculation points) change its type, that is to say, one Rayleigh-wave mode will contain different mode types. This mode type conversion will cause the mode-kissing phenomenon in dispersion images. Numerical tests indicate that the mode-kissing phenomenon is model dependent and that the existence of strong S-wave velocity contrasts increases the possibility of mode-kissing. The real-world data shows mode misidentification caused by mode-kissing phenomenon will result in higher S-wave velocity of bedrock. It reminds us to pay attention to this phenomenon when some of the underground information is known.

  10. Study on mode-filtered light sensor for methane detection

    Institute of Scientific and Technical Information of China (English)

    Suo Zhu Wu; Shao Min Shuang; Yan Zhang; Zhong Ping Li; Martin M.E Choi; Cai Hong Zhang; Chuan Dong

    2009-01-01

    A novel mode-filtered light gas sensor has been reported.It was constructed by inserting an optical fiber deposited by a thin silicone cladding of cryptophane A into a fused-silica capillary.When different concentration of methane gas was introduced to the sensor,the phenomenon that mode-filtered light intensity decreased with the increasing concentration of methane was observed,And a linear relationship was obtained within the methane concentration range of 0.0-16.0%(v/v).The detection limit was 0.06% (v/v).The mode-filtered light sensor has been exploited to respond to various concentrations of methane gas at room temperature.

  11. Porphyrin-based sensor nanoarchitectonics in diverse physical detection modes.

    Science.gov (United States)

    Ishihara, Shinsuke; Labuta, Jan; Van Rossom, Wim; Ishikawa, Daisuke; Minami, Kosuke; Hill, Jonathan P; Ariga, Katsuhiko

    2014-06-07

    Porphyrins and related families of molecules are important organic modules as has been reflected in the award of the Nobel Prizes in Chemistry in 1915, 1930, 1961, 1962, 1965, and 1988 for work on porphyrin-related biological functionalities. The porphyrin core can be synthetically modified by introduction of various functional groups and other elements, allowing creation of numerous types of porphyrin derivatives. This feature makes porphyrins extremely useful molecules especially in combination with their other interesting photonic, electronic and magnetic properties, which in turn is reflected in their diverse signal input-output functionalities based on interactions with other molecules and external stimuli. Therefore, porphyrins and related macrocycles play a preeminent role in sensing applications involving chromophores. In this review, we discuss recent developments in porphyrin-based sensing applications in conjunction with the new advanced concept of nanoarchitectonics, which creates functional nanostructures based on a profound understanding of mutual interactions between the individual nanostructures and their arbitrary arrangements. Following a brief explanation of the basics of porphyrin chemistry and physics, recent examples in the corresponding fields are discussed according to a classification based on physical modes of detection including optical detection (absorption/photoluminescence spectroscopy and energy and electron transfer processes), other spectral modes (circular dichroism, plasmon and nuclear magnetic resonance), electronic and electrochemical modes, and other sensing modes.

  12. Using smart phone sensors to detect transportation modes.

    Science.gov (United States)

    Xia, Hao; Qiao, Yanyou; Jian, Jun; Chang, Yuanfei

    2014-11-04

    The proliferation of mobile smart devices has led to a rapid increase of location-based services, many of which are amassing large datasets of user trajectory information. Unfortunately, current trajectory information is not yet sufficiently rich to support classification of user transportation modes. In this paper, we propose a method that employs both the Global Positioning System and accelerometer data from smart devices to classify user outdoor transportation modes. The classified modes include walking, bicycling, and motorized transport, in addition to the motionless (stationary) state, for which we provide new depth analysis. In our classification, stationary mode has two sub-modes: stay (remaining in the same place for a prolonged time period; e.g., in a parked vehicle) and wait (remaining at a location for a short period; e.g., waiting at a red traffic light). These two sub-modes present different semantics for data mining applications. We use support vector machines with parameters that are optimized for pattern recognition. In addition, we employ ant colony optimization to reduce the dimension of features and analyze their relative importance. The resulting classification system achieves an accuracy rate of 96.31% when applied to a dataset obtained from 18 mobile users.

  13. Using Smart Phone Sensors to Detect Transportation Modes

    Directory of Open Access Journals (Sweden)

    Hao Xia

    2014-11-01

    Full Text Available The proliferation of mobile smart devices has led to a rapid increase of location-based services, many of which are amassing large datasets of user trajectory information. Unfortunately, current trajectory information is not yet sufficiently rich to support classification of user transportation modes. In this paper, we propose a method that employs both the Global Positioning System and accelerometer data from smart devices to classify user outdoor transportation modes. The classified modes include walking, bicycling, and motorized transport, in addition to the motionless (stationary state, for which we provide new depth analysis. In our classification, stationary mode has two sub-modes: stay (remaining in the same place for a prolonged time period; e.g., in a parked vehicle and wait (remaining at a location for a short period; e.g., waiting at a red traffic light. These two sub-modes present different semantics for data mining applications. We use support vector machines with parameters that are optimized for pattern recognition. In addition, we employ ant colony optimization to reduce the dimension of features and analyze their relative importance. The resulting classification system achieves an accuracy rate of 96.31% when applied to a dataset obtained from 18 mobile users.

  14. Electronic detection of collective modes of an ultracold plasma

    CERN Document Server

    Twedt, K A

    2011-01-01

    Using a new technique to directly detect current induced on a nearby electrode, we measure plasma oscillations in ultracold plasmas, which are influenced by the inhomogeneous and time-varying density and changing neutrality. Electronic detection avoids heating and evaporation dynamics associated with previous measurements and allows us to test the importance of the plasma neutrality. We apply dc and pulsed electric fields to control the electron loss rate and find the charge imbalance of the plasma has a significant effect on the resonant frequency, in excellent agreement with recent predictions suggesting coupling to an edge mode.

  15. Transportation Mode Detection Based on Permutation Entropy and Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2015-01-01

    Full Text Available With the increasing prevalence of GPS devices and mobile phones, transportation mode detection based on GPS data has been a hot topic in GPS trajectory data analysis. Transportation modes such as walking, driving, bus, and taxi denote an important characteristic of the mobile user. Longitude, latitude, speed, acceleration, and direction are usually used as features in transportation mode detection. In this paper, first, we explore the possibility of using Permutation Entropy (PE of speed, a measure of complexity and uncertainty of GPS trajectory segment, as a feature for transportation mode detection. Second, we employ Extreme Learning Machine (ELM to distinguish GPS trajectory segments of different transportation. Finally, to evaluate the performance of the proposed method, we make experiments on GeoLife dataset. Experiments results show that we can get more than 50% accuracy when only using PE as a feature to characterize trajectory sequence. PE can indeed be effectively used to detect transportation mode from GPS trajectory. The proposed method has much better accuracy and faster running time than the methods based on the other features and SVM classifier.

  16. Long-term frequency stabilization system for external cavity diode laser based on mode boundary detection.

    Science.gov (United States)

    Xu, Zhouxiang; Huang, Kaikai; Jiang, Yunfeng; Lu, Xuanhui

    2011-12-01

    We have realized a long-term frequency stabilization system for external cavity diode laser (ECDL) based on mode boundary detection method. In this system, the saturated absorption spectroscopy was used. The current and the grating of the ECDL were controlled by a computer-based feedback control system. By checking if there are mode boundaries in the spectrum, the control system determined how to adjust current to avoid mode hopping. This procedure was executed periodically to ensure the long-term stabilization of ECDL in the absence of mode hops. This diode laser system with non-antireflection coating had operated in the condition of long-term mode-hop-free stabilization for almost 400 h, which is a significant improvement of ECDL frequency stabilization system.

  17. A new vehicle detection method

    Directory of Open Access Journals (Sweden)

    Zebbara Khalid

    2011-09-01

    Full Text Available This paper presents a new vehicle detection method from images acquired by cameras embedded in a moving vehicle. Given the sequence of images, the proposed algorithms should detect out all cars in realtime. Related to the driving direction, the cars can be classified into two types. Cars drive in the same direction as the intelligent vehicle (IV and cars drive in the opposite direction. Due to the distinct features of these two types, we suggest to achieve this method in two main steps. The first one detects all obstacles from images using the so-called association combined with corner detector. The second step is applied to validate each vehicle using AdaBoost classifier. The new method has been applied to different images data and the experimental results validate the efficacy of our method.

  18. A Frequency-Weighted Energy Operator and complementary ensemble empirical mode decomposition for bearing fault detection

    Science.gov (United States)

    Imaouchen, Yacine; Kedadouche, Mourad; Alkama, Rezak; Thomas, Marc

    2017-01-01

    Signal processing techniques for non-stationary and noisy signals have recently attracted considerable attentions. Among them, the empirical mode decomposition (EMD) which is an adaptive and efficient method for decomposing signals from high to low frequencies into intrinsic mode functions (IMFs). Ensemble EMD (EEMD) is proposed to overcome the mode mixing problem of the EMD. In the present paper, the Complementary EEMD (CEEMD) is used for bearing fault detection. As a noise-improved method, the CEEMD not only overcomes the mode mixing, but also eliminates the residual of added white noise persisting into the IMFs and enhance the calculation efficiency of the EEMD method. Afterward, a selection method is developed to choose relevant IMFs containing information about defects. Subsequently, a signal is reconstructed from the sum of relevant IMFs and a Frequency-Weighted Energy Operator is tailored to extract both the amplitude and frequency modulations from the selected IMFs. This operator outperforms the conventional energy operator and the enveloping methods, especially in the presence of strong noise and multiple vibration interferences. Furthermore, simulation and experimental results showed that the proposed method improves performances for detecting the bearing faults. The method has also high computational efficiency and is able to detect the fault at an early stage of degradation.

  19. Employing incomplete complex modes for model updating and damage detection of damped structures

    Institute of Scientific and Technical Information of China (English)

    LI HuaJun; LIU FuShun; HU Sau-Lon James

    2008-01-01

    In the study of finite element model updating or damage detection, most papers are devoted to undamped systems. Thus, their objective has been exclusively re-stricted to the correction of the mass and stiffness matrices. In contrast, this paper performs the model updating and damage detection for damped structures. A theoretical contribution of this paper is to extend the cross-model cross-mode (CMCM) method to simultaneously update the mass, damping and stiffness matri-ces of a finite element model when only few spatially incomplete, complex-valued modes are available. Numerical studies are conducted for a 30-DOF (degree-of-freedom) cantilever beam with multiple damaged elements, as the measured modes are synthesized from finite element models. The numerical results reveal that ap-plying the CMCM method, together with an iterative Guyan reduction scheme, can yield good damage detection in general. When the measured modes utilized in the CMCM method are corrupted with irregular errors, assessing damage at the loca-tion that possesses larger modal strain energy is less sensitive to the corrupted modes.

  20. Employing incomplete complex modes for model updating and damage detection of damped structures

    Institute of Scientific and Technical Information of China (English)

    HU; Sau-Lon; James

    2008-01-01

    In the study of finite element model updating or damage detection,most papers are devoted to undamped systems.Thus,their objective has been exclusively restricted to the correction of the mass and stiffness matrices.In contrast,this paper performs the model updating and damage detection for damped structures.A theoretical contribution of this paper is to extend the cross-model cross-mode(CMCM) method to simultaneously update the mass,damping and stiffness matrices of a finite element model when only few spatially incomplete,complex-valued modes are available.Numerical studies are conducted for a 30-DOF(degree-of-freedom) cantilever beam with multiple damaged elements,as the measured modes are synthesized from finite element models.The numerical results reveal that applying the CMCM method,together with an iterative Guyan reduction scheme,can yield good damage detection in general.When the measured modes utilized in the CMCM method are corrupted with irregular errors,assessing damage at the location that possesses larger modal strain energy is less sensitive to the corrupted modes.

  1. Anomaly Detection in Test Equipment via Sliding Mode Observers

    Science.gov (United States)

    Solano, Wanda M.; Drakunov, Sergey V.

    2012-01-01

    Nonlinear observers were originally developed based on the ideas of variable structure control, and for the purpose of detecting disturbances in complex systems. In this anomaly detection application, these observers were designed for estimating the distributed state of fluid flow in a pipe described by a class of advection equations. The observer algorithm uses collected data in a piping system to estimate the distributed system state (pressure and velocity along a pipe containing liquid gas propellant flow) using only boundary measurements. These estimates are then used to further estimate and localize possible anomalies such as leaks or foreign objects, and instrumentation metering problems such as incorrect flow meter orifice plate size. The observer algorithm has the following parts: a mathematical model of the fluid flow, observer control algorithm, and an anomaly identification algorithm. The main functional operation of the algorithm is in creating the sliding mode in the observer system implemented as software. Once the sliding mode starts in the system, the equivalent value of the discontinuous function in sliding mode can be obtained by filtering out the high-frequency chattering component. In control theory, "observers" are dynamic algorithms for the online estimation of the current state of a dynamic system by measurements of an output of the system. Classical linear observers can provide optimal estimates of a system state in case of uncertainty modeled by white noise. For nonlinear cases, the theory of nonlinear observers has been developed and its success is mainly due to the sliding mode approach. Using the mathematical theory of variable structure systems with sliding modes, the observer algorithm is designed in such a way that it steers the output of the model to the output of the system obtained via a variety of sensors, in spite of possible mismatches between the assumed model and actual system. The unique properties of sliding mode control

  2. Method for detecting biological toxins

    Energy Technology Data Exchange (ETDEWEB)

    Ligler, F.S.; Campbell, J.R.

    1992-01-01

    Biological toxins are indirectly detected by using polymerase chain reaction to amplify unique nucleic acid sequences coding for the toxins or enzymes unique to toxin synthesis. Buffer, primers coding for the unique nucleic acid sequences and an amplifying enzyme are added to a sample suspected of containing the toxin. The mixture is then cycled thermally to exponentially amplify any of these unique nucleic acid sequences present in the sample. The amplified sequences can be detected by various means, including fluorescence. Detection of the amplified sequences is indicative of the presence of toxin in the original sample. By using more than one set of labeled primers, the method can be used to simultaneously detect several toxins in a sample.

  3. Mode perturbation method for optimal guided wave mode and frequency selection.

    Science.gov (United States)

    Philtron, J H; Rose, J L

    2014-09-01

    With a thorough understanding of guided wave mechanics, researchers can predict which guided wave modes will have a high probability of success in a particular nondestructive evaluation application. However, work continues to find optimal mode and frequency selection for a given application. This "optimal" mode could give the highest sensitivity to defects or the greatest penetration power, increasing inspection efficiency. Since material properties used for modeling work may be estimates, in many cases guided wave mode and frequency selection can be adjusted for increased inspection efficiency in the field. In this paper, a novel mode and frequency perturbation method is described and used to identify optimal mode points based on quantifiable wave characteristics. The technique uses an ultrasonic phased array comb transducer to sweep in phase velocity and frequency space. It is demonstrated using guided interface waves for bond evaluation. After searching nearby mode points, an optimal mode and frequency can be selected which has the highest sensitivity to a defect, or gives the greatest penetration power. The optimal mode choice for a given application depends on the requirements of the inspection.

  4. Anti noise system and method using broadband radiation modes

    NARCIS (Netherlands)

    Berkhoff, Arthur Perry

    2005-01-01

    Anti noise system and method, in particular for suppressing sound radiated from a structure, using a formulation of the most efficiently radiating vibration patterns of a vibrating body, the radiation modes, in the time domain. The radiation modes can be used to arrive at efficient weighting schemes

  5. Dual collection mode optical microscope with single-pixel detection

    Science.gov (United States)

    Rodríguez, A. D.; Clemente, P.; Fernández-Alonso, Mercedes; Tajahuerce, E.; Lancis, J.

    2015-07-01

    In this work we have developed a single-pixel optical microscope that provides both re ection and transmission images of the sample under test by attaching a diamond pixel layout DMD to a commercial inverted microscope. Our system performs simultaneous measurements of re ection and transmission modes. Besides, in contrast with a conventional system, in our single-element detection system both images belong, unequivocally, to the same plane of the sample. Furthermore, we have designed an algorithm to modify the shape of the projected patterns that improves the resolution and prevents the artifacts produced by the diamond pixel architecture.

  6. Adjunct methods for caries detection

    DEFF Research Database (Denmark)

    Twetman, Svante; Axelsson, Susanna Bihari; Dahlén, Gunnar

    2012-01-01

    evidence for diagnostic accuracy regarding fiber-optic methods and quantitative light-induced fluorescence (+OOO). The electrical methods and laser fluorescence could be useful adjuncts to visual-tactile and radiographic examinations, especially on occlusal surfaces in permanent and primary molars......Abstract Objective. To assess the diagnostic accuracy of adjunct methods used to detect and quantify dental caries. Study design. A systematic literature search for relevant papers was conducted with pre-determined inclusion and exclusion criteria. Abstracts and full text articles were assessed...... independently by two reviewers. The study characteristics were compiled in tables and quality graded according to the QUADAS tool. The level of evidence for each diagnostic technology (fiber-optic methods, fluorescence methods, electrical methods) was based on studies of high or moderate quality according...

  7. Damage Detection by the Mode-Selectable Magnetostrictive Transducer for Cylindrical Ferromagnetic Waveguides

    Science.gov (United States)

    Kim, Youngkyu; Kim, Ikkyu; Kim, Yoon Young

    2004-02-01

    In recent years, ultrasonic inspection techniques adopting magnetostrictive effects have received much attention, because they are non-destructive and require no direct physical contact with target systems. By selecting the desired wave mode and thus rejecting the unwanted modes amongst propagating waves in cylindrical ferromagnetic waveguides, we can effectively detect various types of flaws. However, a bending wave mode selecting technique, in particular, has not been fully developed yet. The purpose of this work is to present a technique to select either bending or longitudinal waves alone from compound waves propagating in ferromagnetic cylindrical waveguide. To achieve this goal, a new bias magnet configuration suitable for bending mode selection is suggested. The experimental results verify the effectiveness of the proposed method.

  8. Compressive sensing based spinning mode detections by in-duct microphone arrays

    Science.gov (United States)

    Yu, Wenjun; Huang, Xun

    2016-05-01

    This paper presents a compressive sensing based experimental method for detecting spinning modes of sound waves propagating inside a cylindrical duct system. This method requires fewer dynamic pressure sensors than the number required by the Shannon-Nyquist sampling theorem so long as the incident waves are sparse in spinning modes. In this work, the proposed new method is firstly validated by preparing some of the numerical simulations with representative set-ups. Then, a duct acoustic testing rig with a spinning mode synthesiser and an in-duct microphone array is built to experimentally demonstrate the new approach. Both the numerical simulations and the experiment results are satisfactory, even when the practical issue of the background noise pollution is taken into account. The approach is beneficial for sensory array tests of silent aeroengines in particular and some other engineering systems with duct acoustics in general.

  9. Dust Detection Mode of the Hayabusa2 LIDAR

    Science.gov (United States)

    Senshu, H.; Oshigami, S.; Kobayashi, M.; Yamada, R.; Namiki, N.; Noda, H.; Ishihara, Y.; Mizuno, T.

    2017-07-01

    We aim to use light detection and ranging (LIDAR) to detect dust grains that might be present around asteroid (162173) Ryugu (1999 JU3), the target of the Hayabusa2 mission. LIDAR is currently used for observing atmospheric aerosols on Earth by measuring the time profile of the return pulse (received light). In the case of Hayabusa2, LIDAR will be used only to determine whether the energy flux of the return pulse exceeds a certain threshold every 133.33 ns. This simplification significantly reduces the amount of down link data. The profile of the return pulse is estimated from iterative observations by changing the thresholds. Here, the performance of the dust counter mode is examined using a breadboard model, a flight model, and an engineering model. For these tests, we develop a new testing device to simulate various time profiles of the return pulse. We also estimate the lower bound of the number density of dust grains that can be detected. It is shown that the LIDAR on board Hayabusa2 is capable of detecting asteroidal dust if dust grains with size similar to the Hayabusa sample exist around the target body and their number density exceeds 105 m^{-3}.

  10. Quantum dot based detections of propagating plasmonic modes excited by bowtie antennas

    Science.gov (United States)

    Wen, Jing; Wang, Kang; Feng, Hui; Lv, Yating; Chen, Jiannong; Zhang, Dawei

    2017-03-01

    Propagating plasmonic modes excited by bowtie apertures based on emissions from a layer of CdSe/ZnS quantum dots are experimentally detected. The mode distributions with a cladding of 20 nm thick Al2O3 film in between the silver and the quantum dot layers are more homogenous compared to the uncoated structure. The variation discipline of the effective indexes and the decay lengths of the plasmonic modes are discussed for various refractive indexes and thicknesses of the cladding. The three dimensional field distributions of the structure are simulated and the plasmonic fields are only excited in and around the cladding layer on top of the silver film. Such quantum dots based detection methods are promising tools for simultaneous imaging of near field optical distributions in integrated plasmonic nano-circuits.

  11. Survey of Anomaly Detection Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ng, B

    2006-10-12

    This survey defines the problem of anomaly detection and provides an overview of existing methods. The methods are categorized into two general classes: generative and discriminative. A generative approach involves building a model that represents the joint distribution of the input features and the output labels of system behavior (e.g., normal or anomalous) then applies the model to formulate a decision rule for detecting anomalies. On the other hand, a discriminative approach aims directly to find the decision rule, with the smallest error rate, that distinguishes between normal and anomalous behavior. For each approach, we will give an overview of popular techniques and provide references to state-of-the-art applications.

  12. Rapid detection of hemagglutination using restrictive microfluidic channels equipped with waveguide-mode sensors

    Science.gov (United States)

    Ashiba, Hiroki; Fujimaki, Makoto; Awazu, Koichi; Fu, Mengying; Ohki, Yoshimichi; Tanaka, Torahiko; Makishima, Makoto

    2016-02-01

    Hemagglutination is utilized for various immunological assays, including blood typing and virus detection. Herein, we describe a method of rapid hemagglutination detection based on a microfluidic channel installed on an optical waveguide-mode sensor. Human blood samples mixed with hemagglutinating antibodies associated with different blood groups were injected into the microfluidic channel, and reflectance spectra of the samples were measured after stopping the flow. The agglutinated and nonagglutinated samples were distinguishable by the alterations in their reflectance spectra with time; the microfluidic channels worked as spatial restraints for agglutinated red blood cells. The demonstrated system allowed rapid hemagglutination detection within 1 min. The suitable height of the channels was also discussed.

  13. Travel Mode Detection with Varying Smartphone Data Collection Frequencies.

    Science.gov (United States)

    Shafique, Muhammad Awais; Hato, Eiji

    2016-05-18

    Smartphones are becoming increasingly popular day-by-day. Modern smartphones are more than just calling devices. They incorporate a number of high-end sensors that provide many new dimensions to smartphone experience. The use of smartphones, however, can be extended from the usual telecommunication field to applications in other specialized fields including transportation. Sensors embedded in the smartphones like GPS, accelerometer and gyroscope can collect data passively, which in turn can be processed to infer the travel mode of the smartphone user. This will solve most of the shortcomings associated with conventional travel survey methods including biased response, no response, erroneous time recording, etc. The current study uses the sensors' data collected by smartphones to extract nine features for classification. Variables including data frequency, moving window size and proportion of data to be used for training, are dealt with to achieve better results. Random forest is used to classify the smartphone data among six modes. An overall accuracy of 99.96% is achieved, with no mode less than 99.8% for data collected at 10 Hz frequency. The accuracy is observed to decrease with decrease in data frequency, but at the same time the computation time also decreases.

  14. Travel Mode Detection with Varying Smartphone Data Collection Frequencies

    Directory of Open Access Journals (Sweden)

    Muhammad Awais Shafique

    2016-05-01

    Full Text Available Smartphones are becoming increasingly popular day-by-day. Modern smartphones are more than just calling devices. They incorporate a number of high-end sensors that provide many new dimensions to smartphone experience. The use of smartphones, however, can be extended from the usual telecommunication field to applications in other specialized fields including transportation. Sensors embedded in the smartphones like GPS, accelerometer and gyroscope can collect data passively, which in turn can be processed to infer the travel mode of the smartphone user. This will solve most of the shortcomings associated with conventional travel survey methods including biased response, no response, erroneous time recording, etc. The current study uses the sensors’ data collected by smartphones to extract nine features for classification. Variables including data frequency, moving window size and proportion of data to be used for training, are dealt with to achieve better results. Random forest is used to classify the smartphone data among six modes. An overall accuracy of 99.96% is achieved, with no mode less than 99.8% for data collected at 10 Hz frequency. The accuracy is observed to decrease with decrease in data frequency, but at the same time the computation time also decreases.

  15. Multihit mode direct-detection laser radar system using a Geiger-mode avalanche photodiode.

    Science.gov (United States)

    Oh, Min Seok; Kong, Hong Jin; Kim, Tae Hoon; Hong, Keun Ho; Kim, Byung Wook; Park, Dong Jo

    2010-03-01

    In this paper, a direct-detection laser radar system that uses a Geiger-mode avalanche photodiode (GAPD) of relatively short dead time (45 ns) is described. A passively Q-switched microchip laser is used as a laser source and a compact peripheral component interconnect system, which includes a time-to-digital converter (TDC), is set up for fast signal processing. With both the GAPD and the TDC functioning multistop acquisition, the system operates in a multihit mode. The software for the three-dimensional visualization and an algorithm for the removal of noise are developed. It is shown that the single-shot precision of the system is approximately 10 cm (sigma) and the precision is improved by increasing the number of laser pulses to be averaged so that the precision of approximately 1 cm (sigma) was acquired with more than 150 laser pulses scattered from the target. The accuracy of the system is measured to be 12 cm when the energy of the emitted laser pulse varies with a factor of 7.

  16. Hemagglutination detection for blood typing based on waveguide-mode sensors

    Directory of Open Access Journals (Sweden)

    Hiroki Ashiba

    2015-03-01

    Full Text Available ABO and Rh(D blood typing is one of the most important tests performed prior to blood transfusion. Although on-site blood testing is desirable for expedient blood transfusion procedure, most conventional methods and instruments lack the required usability or portability. Here, we describe a novel method, based on the detection of hemagglutination using an optical waveguide-mode sensor, for on-site use. The reflectance spectrum of blood alone and that of blood mixed with antibody reagents was measured using the waveguide-mode sensor. Differences in reflectance by agglutinated and non-agglutinated blood samples were observed at the bottom of the spectral dips; due to differences in the manner in which red blood cells interacted with the surface of the sensor chip. Following the addition of the antibody, blood types A, B, O, and AB were clearly distinguishable and Rh(D typing was also possible using the waveguide-mode sensor. Furthermore, the waveguide-mode-based measurement exhibited the potential to detect weak agglutination, which is difficult for human eyes to distinguish. Thus, this method holds great promise for application in novel on-site test instruments.

  17. Detection of Chondromalacia Patellae by Analysis of Intrinsic Mode Functions in Knee-Joint Vibration Signals

    Institute of Scientific and Technical Information of China (English)

    WU Yun-feng; CAI Su-xian; XU Fang; SHI Lei; Sridhar Krishnan

    2014-01-01

    This paper presents the knee-joint vibration signal processing and pathological localization procedures using the empirical mode decomposition for patients with chondromalacia patellae. The artifacts of baseline wander and random noise were identified in the decomposed monotonic trend and intrinsic mode functions (IMF) using the modeling method of probability density function and the confidence limit criterion. Then, the fluctuation parts in the signal were detected by the signal method turning for count. The results demonstrated that the quality of reconstructed signal can be greatly improved, with the removal of the baseline wander (adaptive trend) and the Gaussian distributed random noise. By detecting the turn signals in the artifact-free signal, the pathological segments related to chondromalacia patellae can be effectively localized with the beginning and ending points of the span of turn signals.

  18. Explosives detection system and method

    Science.gov (United States)

    Reber, Edward L.; Jewell, James K.; Rohde, Kenneth W.; Seabury, Edward H.; Blackwood, Larry G.; Edwards, Andrew J.; Derr, Kurt W.

    2007-12-11

    A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

  19. Highly sensitive dual mode electrochemical platform for microRNA detection

    Science.gov (United States)

    Jolly, Pawan; Batistuti, Marina R.; Miodek, Anna; Zhurauski, Pavel; Mulato, Marcelo; Lindsay, Mark A.; Estrela, Pedro

    2016-11-01

    MicroRNAs (miRNAs) play crucial regulatory roles in various human diseases including cancer, making them promising biomarkers. However, given the low levels of miRNAs present in blood, their use as cancer biomarkers requires the development of simple and effective analytical methods. Herein, we report the development of a highly sensitive dual mode electrochemical platform for the detection of microRNAs. The platform was developed using peptide nucleic acids as probes on gold electrode surfaces to capture target miRNAs. A simple amplification strategy using gold nanoparticles has been employed exploiting the inherent charges of the nucleic acids. Electrochemical impedance spectroscopy was used to monitor the changes in capacitance upon any binding event, without the need for any redox markers. By using thiolated ferrocene, a complementary detection mode on the same sensor was developed where the increasing peaks of ferrocene were recorded using square wave voltammetry with increasing miRNA concentration. This dual-mode approach allows detection of miRNA with a limit of detection of 0.37 fM and a wide dynamic range from 1 fM to 100 nM along with clear distinction from mismatched target miRNA sequences. The electrochemical platform developed can be easily expanded to other miRNA/DNA detection along with the development of microarray platforms.

  20. A hybrid formulation of a component mode synthesis method

    Science.gov (United States)

    Farhat, Charbel; Geradin, Michel

    1992-01-01

    Component mode synthesis is a substructuring technique frequently employed in structural dynamics. In this method, a given structure is subdivided into components or substructures, each of which is analyzed independently for natural frequencies and for mode shapes. The substructure mode shapes are then assembled to give displacement shapes or load patterns of the original structure. An analytical justification of the basic concept is presented using spectral decompositions, and a variant substructuring approach where intersubstructure continuity is enforced in a weak form is derived. This leads to a hybrid formulation of the basic method which is particularly suitable for assembling heterogeneous substructures and analyzing nonconforming and incompatible finite element substructure models. For problems where both the basic and hybrid methods are applicable, the hybrid variant can be computationally more advantageous.

  1. Detection of perturbed quantization class stego images based on possible change modes

    Science.gov (United States)

    Zhang, Yi; Liu, Fenlin; Yang, Chunfang; Luo, Xiangyang; Song, Xiaofeng

    2015-11-01

    To improve the detection performance for perturbed quantization (PQ) class [PQ, energy-adaptive PQ (PQe), and texture-adaptive PQ (PQt)] stego images, a detection method based on possible change modes is proposed. First, by using the relationship between the changeable coefficients used for carrying secret messages and the second quantization steps, the modes having even second quantization steps are identified as possible change modes. Second, by referencing the existing features, the modified features that can accurately capture the embedding changes based on possible change modes are extracted. Next, feature sensitivity analyses based on the modifications performed before and after the embedding are carried out. These analyses show that the modified features are more sensitive to the original features. Experimental results indicate that detection performance of the modified features is better than that of the corresponding original features for three typical feature models [Cartesian calibrated PEVny (ccPEV), Cartesian calibrated co-occurrence matrix features (CF), and JPEG rich model (JRM)], and the integrated feature consisting of enhanced histogram features (EHF) and the modified JRM outperforms two current state-of-the-art feature models, namely, phase aware projection model (PHARM) and Gabor rich model (GRM).

  2. Motion-mode energy method for vehicle dynamics analysis and control

    Science.gov (United States)

    Zhang, Nong; Wang, Lifu; Du, Haiping

    2014-01-01

    Vehicle motion and vibration control is a fundamental motivation for the development of advanced vehicle suspension systems. In a vehicle-fixed coordinate system, the relative motions of the vehicle between body and wheel can be classified into several dynamic stages based on energy intensity, and can be decomposed into sets of uncoupled motion-modes according to modal parameters. Vehicle motions are coupled, but motion-modes are orthogonal. By detecting and controlling the predominating vehicle motion-mode, the system cost and energy consumption of active suspensions could be reduced. A motion-mode energy method (MEM) is presented in this paper to quantify the energy contribution of each motion-mode to vehicle dynamics in real time. The control of motion-modes is prioritised according to the level of motion-mode energy. Simulation results on a 10 degree-of-freedom nonlinear full-car model with the magic-formula tyre model illustrate the effectiveness of the proposed MEM. The contribution of each motion-mode to the vehicle's dynamic behaviour is analysed under different excitation inputs from road irregularities, directional manoeuvres and braking. With the identified dominant motion-mode, novel cost-effective suspension systems, such as active reconfigurable hydraulically interconnected suspension, can possibly be used to control full-car motions with reduced energy consumption. Finally, discussion, conclusions and suggestions for future work are provided.

  3. Surveillance system and method having an operating mode partitioned fault classification model

    Science.gov (United States)

    Bickford, Randall L. (Inventor)

    2005-01-01

    A system and method which partitions a parameter estimation model, a fault detection model, and a fault classification model for a process surveillance scheme into two or more coordinated submodels together providing improved diagnostic decision making for at least one determined operating mode of an asset.

  4. Photoneutron spectrum measured with Bonner Spheres in Planetary method mode

    Energy Technology Data Exchange (ETDEWEB)

    Benites R, J. [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calz. de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Apdo. Postal 336, 98000 Zacatecas (Mexico); Velazquez F, J., E-mail: jlbenitesr@prodigy.net.mx [Universidad Autonoma de Nayarit, Posgrado en Ciencias Biologico Agropecuarias, Carretera Tepic-Compostela Km 9, 63780 Jalisco-Nayarit (Mexico)

    2012-10-15

    We measured the spectrum of photoneutrons at 100 cm isocenter linear accelerator (Linac) Varian ix operating at 15 MV Bremsstrahlung mode. In this process was used a radiation field of 20 x 20 cm{sup 2} at a depth of 5 cm in a solid water phantom with dimensions of 30 x 30 x 15 cm{sup 3}. The measurement was performed with a system using it Bonner Spheres spectrometric method Planetary mode. As neutron detector of the spectrometer is used thermoluminescent dosimeters pairs of type 600 and 700. (Author)

  5. Outlier Detection Method Use for the Network Flow Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Rimas Ciplinskas

    2016-06-01

    Full Text Available New and existing methods of cyber-attack detection are constantly being developed and improved because there is a great number of attacks and the demand to protect from them. In prac-tice, current methods of attack detection operates like antivirus programs, i. e. known attacks signatures are created and attacks are detected by using them. These methods have a drawback – they cannot detect new attacks. As a solution, anomaly detection methods are used. They allow to detect deviations from normal network behaviour that may show a new type of attack. This article introduces a new method that allows to detect network flow anomalies by using local outlier factor algorithm. Accom-plished research allowed to identify groups of features which showed the best results of anomaly flow detection according the highest values of precision, recall and F-measure.

  6. Automatic Lumen Detection on Longitudinal Ultrasound B-Mode Images of the Carotid Using Phase Symmetry

    Directory of Open Access Journals (Sweden)

    José Rouco

    2016-03-01

    Full Text Available This article describes a method that improves the performance of previous approaches for the automatic detection of the common carotid artery (CCA lumen centerline on longitudinal B-mode ultrasound images. We propose to detect several lumen centerline candidates using local symmetry analysis based on local phase information of dark structures at an appropriate scale. These candidates are analyzed with selection mechanisms that use symmetry, contrast or intensity features in combination with position-based heuristics. Several experimental results are provided to evaluate the robustness and performance of the proposed method in comparison with previous approaches. These results lead to the conclusion that our proposal is robust to noise, lumen artifacts, contrast variations and that is able to deal with the presence of CCA-like structures, significantly improving the performance of our previous approach, from 87.5% ± 0.7% of correct detections to 98.3% ± 0.3% in a set of 200 images.

  7. Rapid Detection of Microorganisms Based on Active and Passive Modes of QCM

    Directory of Open Access Journals (Sweden)

    Zdeněk Farka

    2014-12-01

    Full Text Available Label-free immunosensors are well suited for detection of microorganisms because of their fast response and reasonable sensitivity comparable to infection doses of common pathogens. Active (lever oscillator and frequency counter and passive (impedance analyzer modes of quartz crystal microbalance (QCM were used and compared for rapid detection of three strains of E. coli. Different approaches for antibody immobilization were compared, the immobilization of reduced antibody using Sulfo‑SMCC was most effective achieving the limit of detection (LOD 8 × 104 CFU·mL−1 in 10 min. For the passive mode, software evaluating impedance characteristics in real-time was developed and used. Almost the same results were achieved using both active and passive modes confirming that the sensor properties are not limited by the frequency evaluation method but mainly by affinity of the antibody. Furthermore, reference measurements were done using surface plasmon resonance. Effect of condition of cells on signal was observed showing that cells ruptured by ultrasonication provided slightly higher signal changes than intact microbes.

  8. Damage detection and quantification using mode curvature variation on framed structures: analysis of the preliminary results

    Science.gov (United States)

    Iacovino, Chiara; Ditommaso, Rocco; Auletta, Gianluca; Ponzo, Felice C.

    2017-04-01

    Continuous monitoring based on vibrational identification methods is increasingly employed for the evaluation of the state of health of existing buildings after strong motion earthquake. Different damage identification methods are based on the variations of damage indices defined in terms modal (eigenfrequencies, mode shapes, and modal damping) and/or non-modal parameters. Most of simplified methods for structural health monitoring and damage detection are based on the evaluation of the dynamic characteristics evolution associated to the fundamental mode of vibration of a monitored structure. Aim of this work is the upgrade of an existing method for damage localization on framed structures during a moderate/destructive earthquake. The existing version of the method is based on the comparison of the geometric characteristics (with particular reference to the mode curvature) exhibited by the structures, related to fundamental mode of vibration, before and during an earthquake. The approach is based on the use of a nonlinear filter, the band-variable filter, based on the Stockwell Transform able to extract the nonlinear response of each mode of vibration. The new version of the method provides the possibility to quantify a possible damage occurred on the monitored structure linking the mode curvature variation with the maximum inter-story drift. This paper shows the preliminary results obtained from several simulations on nonlinear numerical models of reinforced concrete framed structures, designed for only gravity loads, without and with the presence of infill panels. Furthermore, a correlation between maximum mode curvature difference and maximum inter-story drift has been defined for the different numerical models in order to quantify the structural damage. Acknowledgements This study was partially funded by the Italian Department of Civil Protection within the project DPC-RELUIS 2016 - RS4 ''Seismic observatory of structures and health monitoring'' and by the

  9. NOLB: Nonlinear Rigid Block Normal Mode Analysis Method

    OpenAIRE

    Hoffmann, Alexandre; Grudinin, Sergei

    2017-01-01

    International audience; We present a new conceptually simple and computationally efficient method for non-linear normal mode analysis called NOLB. It relies on the rotations-translations of blocks (RTB) theoretical basis developed by Y.-H. Sanejouand and colleagues. We demonstrate how to physically interpret the eigenvalues computed in the RTB basis in terms of angular and linear velocities applied to the rigid blocks and how to construct a non-linear extrapolation of motion out of these velo...

  10. Kepler detected gravity-mode period spacings in a red giant star

    NARCIS (Netherlands)

    Beck, P.G.; Bedding, T.R.; Mosser, B.; Stello, D.; Garcia, R.A.; Kallinger, T.; Hekker, S.; Elsworth, Y.; Frandsen, S.; Carrier, F.; de Ridder, J.; Aerts, C.; White, T.R.; Huber, D.; Dupret, M. A.; Montalban, J.; Miglio, A.; Noels, A.; Chaplin, W.J.; Kjeldsen, H.; Christensen-Dalsgaard, J.; Gilliland, R.L.; Brown, T.M.; Kawaler, S.D.; Mathur, S.; Jenkins, J.M.

    2011-01-01

    Stellar interiors are inaccessible through direct observations. For this reason, helioseismologists made use of the Sun’s acoustic oscillation modes to tune models of its structure. The quest to detect modes that probe the solar core has been ongoing for decades. We report the detection of mixed

  11. Comparison of Methods for Oscillation Detection

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Trangbæk, Klaus

    2006-01-01

    This paper compares a selection of methods for detecting oscillations in control loops. The methods are tested on measurement data from a coal-fired power plant, where some oscillations are occurring. Emphasis is put on being able to detect oscillations without having a system model and without...... using process knowledge. The tested methods show potential for detecting the oscillations, however, transient components in the signals cause false detections as well, motivating usage of models in order to remove the expected signals behavior....

  12. Adapted G-mode Clustering Method applied to Asteroid Taxonomy

    Science.gov (United States)

    Hasselmann, Pedro H.; Carvano, Jorge M.; Lazzaro, D.

    2013-11-01

    The original G-mode was a clustering method developed by A. I. Gavrishin in the late 60's for geochemical classification of rocks, but was also applied to asteroid photometry, cosmic rays, lunar sample and planetary science spectroscopy data. In this work, we used an adapted version to classify the asteroid photometry from SDSS Moving Objects Catalog. The method works by identifying normal distributions in a multidimensional space of variables. The identification starts by locating a set of points with smallest mutual distance in the sample, which is a problem when data is not planar. Here we present a modified version of the G-mode algorithm, which was previously written in FORTRAN 77, in Python 2.7 and using NumPy, SciPy and Matplotlib packages. The NumPy was used for array and matrix manipulation and Matplotlib for plot control. The Scipy had a import role in speeding up G-mode, Scipy.spatial.distance.mahalanobis was chosen as distance estimator and Numpy.histogramdd was applied to find the initial seeds from which clusters are going to evolve. Scipy was also used to quickly produce dendrograms showing the distances among clusters. Finally, results for Asteroids Taxonomy and tests for different sample sizes and implementations are presented.

  13. A Dual-Mode UWB Wireless Platform with Random Pulse Length Detection for Remote Patient Monitoring

    DEFF Research Database (Denmark)

    Reyes, Carlos; Bisbe, Sergi; Shen, Ming

    2013-01-01

    on a single hardware platform, but it is capable of both monitoring and data transmission. This is achieved by employing a new random pulse length detection method that allows data transmission by using a modulated monitoring signal. To prove the proposed concept a test system has been built, using commercial......This paper presents a dual-mode ultra-wideband platform for wireless Remote Patient Monitoring (RPM). Existing RPM solutions are typically based on two different hardware platforms; one responsible for medical-data monitoring and one to handle data transmission. The proposed RPM topology is based...

  14. Neutron detection apparatus and method

    Energy Technology Data Exchange (ETDEWEB)

    Derzon, Mark S.; Borek, III, Theodore T.

    2017-08-15

    An apparatus for neutron detection is provided. The apparatus comprises a sensor medium in electrical contact with an electrode arrangement conformed to collect radiation-generated charge from the sensor medium. The sensor medium comprises a borazine and/or a borazine-based polymer.

  15. 3D mode discrete element method with the elastoplastic model

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The three-dimensional mode-deformable discrete element method (3MDEM) is an extended distinct element approach under the assumptions of small strain,finite displacement,and finite rotation of blocks.The deformation of blocks is expressed by the combination of the deformation modes in 3MDEM.In this paper,the elastoplastic constitutive relationship of blocks is implemented on the 3MDEM platform to simulate the integrated process from elasticity to plasticity and finally to fracture.To overcome the shortcomings of the conventional criterion for contact fracturing,a new criterion based on plastic strain is introduced.This approach is verified by two numerical examples.Finally,a cantilever beam is simulated as a comprehensive case study,which went through elastic,elastoplastic,and discontinuous fracture stages.

  16. A New Phase Noise Detection Method

    OpenAIRE

    Yan, Gangfeng

    2015-01-01

    Phase noise is one of the most important parameters in many oscillators. Detecting accurately phase noise for oscillators has importance significance. In this paper, based on correlation operation detection phase noise for oscillators was proposed. This method not only can save a high precision reference oscillator, but also can detect accurately the phase noise of measured oscillator in theory. Detected phase noise of oscillators using this method has very strong utility value.

  17. Sensitive and direct determination of lithium by mixed-mode chromatography and charged aerosol detection.

    Science.gov (United States)

    Dai, Lulu; Wigman, Larry; Zhang, Kelly

    2015-08-21

    A sensitive analytical method using mixed mode HPLC separation coupled with charged aerosol detection (CAD) was developed for quantitative analysis of lithium. The method is capable of separating lithium ion from different drug matrices and other ions in a single run thus eliminating the organic matrix and ionic analyte interferences without extensive sample preparation such as derivatization and extraction. The separation space and chromatographic conditions are defined by systematic studies of the retention behaviors of lithium and potential interfering ions and different type of pharmaceutical APIs (active pharmaceutical ingredients) under reversed-phase, HILIC and cation/anion exchange mechanisms. Compared to other current analytical techniques for lithium analysis, the presented method provides a new approach and demonstrates high sensitivity (0.02ng for LOD and 0.08ng for LOQ in both standard and sample solution). The method has been validated for pharmaceutical samples and can be potentially applied to biological, food and environmental samples.

  18. A review of time-domain and frequency-domain component mode synthesis method

    Science.gov (United States)

    Craig, R. R., Jr.

    1985-01-01

    Hurty (1965) has conducted a dynamic analysis of structural systems using component modes. The component mode synthesis (CMS) procedure considered by him represents a form of substructure coupling analysis which is often utilized in structural dynamics. Time-domain CMS methods employing real modes are discussed, taking into account real component modes, normal modes, redundant constraint modes, rigid-body modes, attachment modes, inertia-relief modes, statically-complete interface mode sets, dynamic component mode supersets, component modal models, the coupling of components, and the classification of methods. Attention is also given to the experimental determination of component mode synthesis parameters, time-domain CMS methods for damped systems, and frequency-domain CMS methods for damped systems.

  19. Comparative research on the methods for measuring the mode deflection angle of cylindrical resonator gyroscope

    Science.gov (United States)

    Wang, Kai; Fan, Zhenfang; Wang, Dongya; Wang, Yanyan; Pan, Yao; Qu, Tianliang; Xu, Guangming

    2016-10-01

    The existence of mode deflection angle in the cylindrical resonator gyroscope (CRG) leads to the signal drift on the detecting nodes of the gyro vibration and significantly decreases the performance of the CRG. Measuring the mode deflection angle efficiently is the foundation of tuning for the imperfect cylindrical shell resonator. In this paper, an optical method based on the measuring gyroscopic resonator's vibration amplitude with the laser Doppler vibrometer and an electrical method based on measuring the output voltage of the electrodes on the resonator are both presented to measure the mode deflection angle. Comparative experiments were implemented to verify the methodology and the results show that both of the two methods could recognize the mode deflection angle efficiently. The precision of the optical method relies on the number and position of testing points distributed on the resonator. The electrical method with simple circuit shows high accuracy of measuring in a less time compared to the optical method and its error source arises from the influence of circuit noise as well as the inconsistent distribution of the piezoelectric electrodes.

  20. Modified robust sliding-mode control method for wafer scanner

    Directory of Open Access Journals (Sweden)

    Yiguang Wang

    2015-03-01

    Full Text Available This article studies the precision motion control of a long-stroke reticle stage driven by the permanent magnet linear motor in wafer scanner. A robust sliding-mode control method is proposed for tracking the reference trajectory in the presence of un-modeled dynamics, parametric uncertainty and external disturbances including force ripple, cogging and friction in the controlled system. A modified sliding-mode term based on the variable structure technique for eliminating the tracking error is employed in the proposed control law. The system stability and tracking convergence of the closed-loop control system are guaranteed by Lyapunov theory theoretically. The feasibility and effectiveness of the proposed method are demonstrated by comparative experiments on a linear motion testbed. The experimental results show that better tracking performance can be achieved by the proposed method compared with the conventional proportional–integral–derivative method and it can be considered as a possible alternative in the precision motion control system.

  1. Kepler Detected Gravity-Mode Period Spacings in a Red Giant Star

    DEFF Research Database (Denmark)

    Beck, P.G.; Bedding, Timothy R.; Mosser, Benoit;

    2011-01-01

    Stellar interiors are inaccessible through direct observations. For this reason, helioseismologists made use of the Sun’s acoustic oscillation modes to tune models of its structure. The quest to detect modes that probe the solar core has been ongoing for decades. We report the detection of mixed ...... modes penetrating all the way to the core of an evolved star from 320 days of observations with the Kepler satellite. The period spacings of these mixed modes are directly dependent on the density gradient between the core region and the convective envelope....

  2. Rapid methods for detection of bacteria

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Andersen, B.Ø.; Miller, M.

    2006-01-01

    Traditional methods for detection of bacteria in drinking water e.g. Heterotrophic Plate Counts (HPC) or Most Probable Number (MNP) take 48-72 hours to give the result. New rapid methods for detection of bacteria are needed to protect the consumers against contaminations. Two rapid methods...

  3. Rapid methods for detection of bacteria

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Andersen, B.Ø.; Miller, M.

    2006-01-01

    Traditional methods for detection of bacteria in drinking water e.g. Heterotrophic Plate Counts (HPC) or Most Probable Number (MNP) take 48-72 hours to give the result. New rapid methods for detection of bacteria are needed to protect the consumers against contaminations. Two rapid methods...

  4. Novelty Detection Methods and Novel Fault Class Detection

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jiafan; HUANG Zhichu; WANG Xiaoming

    2006-01-01

    The ability to detect a new fault class can be a useful feature for an intelligent fault classification and diagnosis system. We adopt two novelty detection methods, the support vector data description (SVDD) and the Parzen density estimation, to represent known fault class samples, and to detect new fault class samples. The experiments on real multi-class bearing fault data show that the SVDD can give both high novelty detection rate and target recognition rate, respectively for the prescribed 'unknown' fault samples and the known fault samples by choosing the appropriate SVDD algorithm parameters; but the Parzen density estimation only give a better novelty detection rate in our experiments.

  5. Colorimetry and SERS dual-mode detection of telomerase activity: combining rapid screening with high sensitivity.

    Science.gov (United States)

    Zong, Shenfei; Wang, Zhuyuan; Chen, Hui; Hu, Guohua; Liu, Min; Chen, Peng; Cui, Yiping

    2014-01-01

    As an important biomarker and therapeutic target, telomerase has attracted considerable attention concerning its detection and monitoring. Here, we present a colorimetry and surface enhanced Raman scattering (SERS) dual-mode telomerase activity detection method, which has several distinctive advantages. First, colorimetric functionality allows rapid preliminary discrimination of telomerase activity by the naked eye. Second, the employment of SERS technique results in greatly improved detection sensitivity. Third, the combination of colorimetry and SERS into one detection system can ensure highly efficacious and sensitive screening of numerous samples. Besides, the avoidance of polymerase chain reaction (PCR) procedures further guarantees fine reliability and simplicity. Generally, the presented method is realized by an "elongate and capture" procedure. To be specific, gold nanoparticles modified with Raman molecules and telomeric repeat complementary oligonucleotide are employed as the colorimetric-SERS bifunctional reporting nanotag, while magnetic nanoparticles functionalized with telomerase substrate oligonucleotide are used as the capturing substrate. Telomerase can synthesize and elongate telomeric repeats onto the capturing substrate. The elongated telomeric repeats subsequently facilitate capturing of the reporting nanotag via hybridization between telomeric repeat and its complementary strand. The captured nanotags can cause a significant difference in the color and SERS intensity of the magnetically separated sediments. Thus both the color and SERS can be used as indicators of the telomerase activity. With fast screening ability and outstanding sensitivity, we anticipate that this method would greatly promote practical application of telomerase-based early-stage cancer diagnosis.

  6. Direct 13C NMR Detection in HPLC Hyphenation Mode

    DEFF Research Database (Denmark)

    Wubshet, Sileshi Gizachew; Johansen, Kenneth; Nyberg, Nils

    2012-01-01

    Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments......, and an acquisition time of 13 h resulted in spectra with adequate signal-to-noise ratios to detect all C-13 signals....

  7. Method of fabricating a whispering gallery mode resonator

    Science.gov (United States)

    Savchenkov, Anatoliy A. (Inventor); Matkso, Andrey B. (Inventor); Iltchenko, Vladimir S. (Inventor); Maleki, Lute (Inventor)

    2011-01-01

    A method of fabricating a whispering gallery mode resonator (WGMR) is provided. The WGMR can be fabricated from a particular material, annealed, and then polished. The WGMR can be repeatedly annealed and then polished. The repeated polishing of the WGMR can be carried out using an abrasive slurry. The abrasive slurry can have a predetermined, constant grain size. Each subsequent polishing of the WGMR can use an abrasive slurry having a grain size that is smaller than the grain size of the abrasive slurry of the previous polishing iteration.

  8. Method of coupled mode for long-range bottom reverberation

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The theory of coupled mode is used for modeling the long-range bottom reverberation in shallow water caused by bottom roughness. The distant bottom reverberation level and spatial coherence of impulsive source are both derived. The results agree with those from the classical reverberation model, and are compared with the experimental data. The influence of source bandwidth and the distance between sources and receivers on the intensity of bottom reverberation are particularly discussed. The method is shown to be available for both the monoand the bi-static cases.

  9. Performance Improvement of Ensemble Empirical Mode Decomposition for Roller Bearings Damage Detection

    Directory of Open Access Journals (Sweden)

    Ali Akbar Tabrizi

    2015-01-01

    Full Text Available Ensemble empirical mode decomposition (EEMD is a noise assisted method widely used for roller bearing damage detection. However, to successfully handle this technique still remains a great challenge: identification of two effective parameters (the amplitude of added noise and the number of ensemble trials, which affect the performances of the EEMD. Although a number of algorithms or values have been proposed, there is no robust guide to select optimal amplitude and the ensemble trial number yet, especially for early damage detection. In this study, a reliable method is proposed to determine the suitable amplitude and the proper number of trials is investigated as well. It is shown that the proposed method (performance improved EEMD achieves higher damage detection success rate and creates larger Margin than the original algorithm. It leads to a substantially low trial numbers required to achieve perfect labelling of samples; in turn this fact leads to considerably less computational cost. The number of real vibration signals is analysed to verify effectiveness and robustness of the proposed method in discriminating and separating the faulty conditions.

  10. An improved method for risk evaluation in failure modes and effects analysis of CNC lathe

    Science.gov (United States)

    Rachieru, N.; Belu, N.; Anghel, D. C.

    2015-11-01

    Failure mode and effects analysis (FMEA) is one of the most popular reliability analysis tools for identifying, assessing and eliminating potential failure modes in a wide range of industries. In general, failure modes in FMEA are evaluated and ranked through the risk priority number (RPN), which is obtained by the multiplication of crisp values of the risk factors, such as the occurrence (O), severity (S), and detection (D) of each failure mode. However, the crisp RPN method has been criticized to have several deficiencies. In this paper, linguistic variables, expressed in Gaussian, trapezoidal or triangular fuzzy numbers, are used to assess the ratings and weights for the risk factors S, O and D. A new risk assessment system based on the fuzzy set theory and fuzzy rule base theory is to be applied to assess and rank risks associated to failure modes that could appear in the functioning of Turn 55 Lathe CNC. Two case studies have been shown to demonstrate the methodology thus developed. It is illustrated a parallel between the results obtained by the traditional method and fuzzy logic for determining the RPNs. The results show that the proposed approach can reduce duplicated RPN numbers and get a more accurate, reasonable risk assessment. As a result, the stability of product and process can be assured.

  11. Damage detection based on mode shapes of a girder bridge constructed from responses of a moving vehicle under impact excitation

    Science.gov (United States)

    Qi, Zhongqiang; Au, Francis T. K.

    2016-04-01

    The vibration mode shapes are often used to identify damage of bridges because the mode shapes are not only important modal properties but also sensitive to damage. However, the key issue is how to conveniently obtain the mode shapes of a bridge in service. Traditional methods invariably require installation of instruments on the bridge for collection of dynamic responses for constructing mode shapes, which are both costly and inconvenient. Therefore a method is developed to construct the mode shapes of simply supported bridges based on Hilbert Transform using only vehicle acceleration response for identification of the location of damage. Firstly, an algorithm is devised to construct the mode shapes by using the dynamic responses extracted from a moving vehicle under impact excitation. Then, based on these intermediate results, the coordinate modal assurance criterion in conjunction with suitable wavelets is used to identify the location of damage. Compared with the traditional methods, the proposed method uses only the information from the moving vehicle. Moreover, additional impact excitation on the vehicle helps to excite the bridge. This helps to improve the accuracy by overcoming the adverse effects of measurement noise and road surface roughness, which leads to high accuracy of damage detection. To verify the feasibility of the proposed method, some numerical studies have been carried out to investigate the effects of measurement noise, road surface roughness and multiple locations of damage on the accuracy of results.

  12. Direct 13C NMR Detection in HPLC Hyphenation Mode

    DEFF Research Database (Denmark)

    Wubshet, Sileshi Gizachew; Johansen, Kenneth; Nyberg, Nils

    2012-01-01

    Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments...... application of HPLC-SPE-NMR analysis using direct-detected (13)C NMR spectra. HPLC column loading, accumulative SPE trappings, and the effect of different elution solvents were evaluated and optimized. A column loading of approximately 600 mug of a prefractionated triterpenoid mixture, six trappings...

  13. Comparison of Methods for Oscillation Detection

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Trangbæk, Klaus

    2006-01-01

    This paper compares a selection of methods for detecting oscillations in control loops. The methods are tested on measurement data from a coal-fired power plant, where some oscillations are occurring. Emphasis is put on being able to detect oscillations without having a system model and without u...... using process knowledge. The tested methods show potential for detecting the oscillations, however, transient components in the signals cause false detections as well, motivating usage of models in order to remove the expected signals behavior....

  14. Sliding mode control method having terminal convergence in finite time

    Science.gov (United States)

    Venkataraman, Subramanian T. (Inventor); Gulati, Sandeep (Inventor)

    1994-01-01

    An object of this invention is to provide robust nonlinear controllers for robotic operations in unstructured environments based upon a new class of closed loop sliding control methods, sometimes denoted terminal sliders, where the new class will enforce closed-loop control convergence to equilibrium in finite time. Improved performance results from the elimination of high frequency control switching previously employed for robustness to parametric uncertainties. Improved performance also results from the dependence of terminal slider stability upon the rate of change of uncertainties over the sliding surface rather than the magnitude of the uncertainty itself for robust control. Terminal sliding mode control also yields improved convergence where convergence time is finite and is to be controlled. A further object is to apply terminal sliders to robot manipulator control and benchmark performance with the traditional computed torque control method and provide for design of control parameters.

  15. Planar quadrature RF transceiver design using common-mode differential-mode (CMDM transmission line method for 7T MR imaging.

    Directory of Open Access Journals (Sweden)

    Ye Li

    Full Text Available The use of quadrature RF magnetic fields has been demonstrated to be an efficient method to reduce transmit power and to increase the signal-to-noise (SNR in magnetic resonance (MR imaging. The goal of this project was to develop a new method using the common-mode and differential-mode (CMDM technique for compact, planar, distributed-element quadrature transmit/receive resonators for MR signal excitation and detection and to investigate its performance for MR imaging, particularly, at ultrahigh magnetic fields. A prototype resonator based on CMDM method implemented by using microstrip transmission line was designed and fabricated for 7T imaging. Both the common mode (CM and the differential mode (DM of the resonator were tuned and matched at 298MHz independently. Numerical electromagnetic simulation was performed to verify the orthogonal B1 field direction of the two modes of the CMDM resonator. Both workbench tests and MR imaging experiments were carried out to evaluate the performance. The intrinsic decoupling between the two modes of the CMDM resonator was demonstrated by the bench test, showing a better than -36 dB transmission coefficient between the two modes at resonance frequency. The MR images acquired by using each mode and the images combined in quadrature showed that the CM and DM of the proposed resonator provided similar B1 coverage and achieved SNR improvement in the entire region of interest. The simulation and experimental results demonstrate that the proposed CMDM method with distributed-element transmission line technique is a feasible and efficient technique for planar quadrature RF coil design at ultrahigh fields, providing intrinsic decoupling between two quadrature channels and high frequency capability. Due to its simple and compact geometry and easy implementation of decoupling methods, the CMDM quadrature resonator can possibly be a good candidate for design blocks in multichannel RF coil arrays.

  16. Planar quadrature RF transceiver design using common-mode differential-mode (CMDM) transmission line method for 7T MR imaging.

    Science.gov (United States)

    Li, Ye; Yu, Baiying; Pang, Yong; Vigneron, Daniel B; Zhang, Xiaoliang

    2013-01-01

    The use of quadrature RF magnetic fields has been demonstrated to be an efficient method to reduce transmit power and to increase the signal-to-noise (SNR) in magnetic resonance (MR) imaging. The goal of this project was to develop a new method using the common-mode and differential-mode (CMDM) technique for compact, planar, distributed-element quadrature transmit/receive resonators for MR signal excitation and detection and to investigate its performance for MR imaging, particularly, at ultrahigh magnetic fields. A prototype resonator based on CMDM method implemented by using microstrip transmission line was designed and fabricated for 7T imaging. Both the common mode (CM) and the differential mode (DM) of the resonator were tuned and matched at 298MHz independently. Numerical electromagnetic simulation was performed to verify the orthogonal B1 field direction of the two modes of the CMDM resonator. Both workbench tests and MR imaging experiments were carried out to evaluate the performance. The intrinsic decoupling between the two modes of the CMDM resonator was demonstrated by the bench test, showing a better than -36 dB transmission coefficient between the two modes at resonance frequency. The MR images acquired by using each mode and the images combined in quadrature showed that the CM and DM of the proposed resonator provided similar B1 coverage and achieved SNR improvement in the entire region of interest. The simulation and experimental results demonstrate that the proposed CMDM method with distributed-element transmission line technique is a feasible and efficient technique for planar quadrature RF coil design at ultrahigh fields, providing intrinsic decoupling between two quadrature channels and high frequency capability. Due to its simple and compact geometry and easy implementation of decoupling methods, the CMDM quadrature resonator can possibly be a good candidate for design blocks in multichannel RF coil arrays.

  17. Detectability of tensor modes in the presence of foregrounds

    CERN Document Server

    Amarie, M; Seljak, U; Amarie, Mihail; Hirata, Christopher; Seljak, Uros

    2005-01-01

    In inflationary models, gravitational waves are produced and generate B-type polarization in the CMB. Since B polarization is only generated by gravity waves it does not suffer from the cosmic variance. A perfect decomposition of the CMB into B-modes and E-modes would require data from the entire sky, which in practice is not possible because of the foreground contaminants. This leads to mixing of E polarization into B, which introduces cosmic variance conta- mination of B polarization and reduces sensitivity to gravity wave amplitude even in absence of detector noise. We present numerical results for the uncertainty in the tensor-to-scalar ratio using the Fisher matrix formalism for various resolutions, using foreground models based on dust maps and assuming 90 GHz operating frequency. We find that the usual scaling delta(T/S) ~ f_sky^(-1/2) is significantly degraded and becomes delta(T/S) ~ f_sky^(-2) for f_sky>0.7. This dependence is affected only weakly by the choice of sky cuts. To achieve a T/S=10^(-3) ...

  18. Grassmann phase space methods for fermions. I. Mode theory

    Science.gov (United States)

    Dalton, B. J.; Jeffers, J.; Barnett, S. M.

    2016-07-01

    In both quantum optics and cold atom physics, the behaviour of bosonic photons and atoms is often treated using phase space methods, where mode annihilation and creation operators are represented by c-number phase space variables, with the density operator equivalent to a distribution function of these variables. The anti-commutation rules for fermion annihilation, creation operators suggest the possibility of using anti-commuting Grassmann variables to represent these operators. However, in spite of the seminal work by Cahill and Glauber and a few applications, the use of Grassmann phase space methods in quantum-atom optics to treat fermionic systems is rather rare, though fermion coherent states using Grassmann variables are widely used in particle physics. The theory of Grassmann phase space methods for fermions based on separate modes is developed, showing how the distribution function is defined and used to determine quantum correlation functions, Fock state populations and coherences via Grassmann phase space integrals, how the Fokker-Planck equations are obtained and then converted into equivalent Ito equations for stochastic Grassmann variables. The fermion distribution function is an even Grassmann function, and is unique. The number of c-number Wiener increments involved is 2n2, if there are n modes. The situation is somewhat different to the bosonic c-number case where only 2 n Wiener increments are involved, the sign of the drift term in the Ito equation is reversed and the diffusion matrix in the Fokker-Planck equation is anti-symmetric rather than symmetric. The un-normalised B distribution is of particular importance for determining Fock state populations and coherences, and as pointed out by Plimak, Collett and Olsen, the drift vector in its Fokker-Planck equation only depends linearly on the Grassmann variables. Using this key feature we show how the Ito stochastic equations can be solved numerically for finite times in terms of c-number stochastic

  19. Detecting magnetic field direction by a micro beam operating in different vibration modes

    Institute of Scientific and Technical Information of China (English)

    Chen Jie; Qin Ming; Huang Qing-An

    2011-01-01

    A new method to detect the magnetic field direction by using a silicon structure is presented in this paper. The structure includes a micro beam and an in-plane coil electrode. When the electrode under a magnetic field is applied with an alternating current,the micro beam is actuated under the effect of the Lorentz forces. Magnetic fields of different directions cause different vibration profiles. The direction of the magnetic field is obtained by measuring the vibration amplitudes of the micro beam,which is driven to work at first- and second-order resonant modes. A micro structure has been fabricated using the bulk micromachined silicon process. A laser Doppler vibrometer system is implemented to measure the vibration amplitudes. The experimental results show that the amplitude of the structure,which depends on the different modes,is a sine or cosine function of the angle of the magnetic field. It agrees well with the simulation result. Currently a resolution of 100 for the magnetic field direction measurement can be obtained using the detecting principle.

  20. Condition monitoring of a wind turbine gearbox using the empirical mode decomposition method and outlier analysis

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadou, Ifigeneia; Manson, G.; Dervilis, N.; Worden, K. [Sheffield Univ. (United Kingdom); Barszcz, T.; Staszewski, W. [AGH Univ. of Science and Technology, Krakow (Poland)

    2012-07-01

    Wind turbines are subject to variable aerodynamic loads and extreme environmental conditions. Wind turbine components fail frequently, resulting in high maintenance costs. For this reason, gearbox condition monitoring becomes important since gearboxes are among the wind turbine components with the most frequent failure observations. The major challenge here is the detection of faults under the time varying operating conditions prevailing in wind turbine systems. This paper analyses wind turbine gearbox vibration data using the empirical mode decomposition method and the statistical discipline of outlier analysis for the damage detection of gearbox tooth faults. The instantaneous characteristics of the signals are obtained with the application of the Hilbert transform. The lowest level of fault detection, the threshold value, is considered and Mahalanobis squared-distance is calculated for the novelty detection problem. (orig.)

  1. Free-Interface Modal Synthesis Based Substructural Damage Detection Method

    Directory of Open Access Journals (Sweden)

    Shanghong Chen

    2014-01-01

    Full Text Available Free-interface modal synthesis method is applied to civil structure, and a substructure method is proposed by introducing the method into global sensitivity method. The substructure expression of the derivatives of eigenvalues and eigenvectors with respect to elemental parameters is obtained. The accuracy of the application of free-interface modal synthesis method is evaluated with different retained modes in substructure, and then the effectiveness of the proposed substructure sensitivity method is illustrated through an 11-storey building under both single- and multidamage cases. Both the damage locations and the extent can be effectively identified. By comparing it with the identical results of global sensitivity method, the proposed method can be faster in detecting the damage location and more stable under multidamage cases. Since this substructure sensitivity method only needs to update sensitivity matrix in the substructure with relative small number of DOFs, it may save much computation effort and become more efficient.

  2. Detecting the amplitude mode of strongly interacting lattice bosons by Bragg scattering.

    Science.gov (United States)

    Bissbort, Ulf; Götze, Sören; Li, Yongqiang; Heinze, Jannes; Krauser, Jasper S; Weinberg, Malte; Becker, Christoph; Sengstock, Klaus; Hofstetter, Walter

    2011-05-20

    We report the first detection of the Higgs-type amplitude mode using Bragg spectroscopy in a strongly interacting condensate of ultracold atoms in an optical lattice. By the comparison of our experimental data with a spatially resolved, time-dependent bosonic Gutzwiller calculation, we obtain good quantitative agreement. This allows for a clear identification of the amplitude mode, showing that it can be detected with full momentum resolution by going beyond the linear response regime. A systematic shift of the sound and amplitude modes' resonance frequencies due to the finite Bragg beam intensity is observed.

  3. New approach to the normal mode method in underwater acoustics

    Institute of Scientific and Technical Information of China (English)

    王宁; 刘进忠

    2002-01-01

    A new approach to the numerical solution of normal mode problems in underwater acoustics is presented, in whichthe corresponding normal mode problem is transformed to the problem of solving a dynamic system. Three applica-tions are considered: (1) the broad band normal mode problem; (2) the range-dependent problem with perturbationproportional to the range parameter; and (3) the evolution of the normal mode with environmental parameters. Anumerical simulation for a broad band problem is performed, and the calculated eigenvalues have good agreement withthose obtained by the standard normal mode code KRAKAN.

  4. Application of Sliding Mode Methods to the Design of Reconfigurable Flight Control Systems

    Science.gov (United States)

    Wells, Scott R.

    2002-01-01

    Observer-based sliding mode control is investigated for application to aircraft reconfigurable flight control. A comprehensive overview of reconfigurable flight control is given, including, a review of the current state-of-the-art within the subdisciplines of fault detection, parameter identification, adaptive control schemes, and dynamic control allocation. Of the adaptive control methods reviewed, sliding mode control (SMC) appears very promising due its property of invariance to matched uncertainty. An overview of sliding mode control is given and its remarkable properties are demonstrated by example. Sliding mode methods, however, are difficult to implement because unmodeled parasitic dynamics cause immediate and severe instability. This presents a challenge for all practical applications with limited bandwidth actuators. One method to deal with parasitic dynamics is the use of an asymptotic observer in the feedback path. Observer-based SMC is investigated, and a method for selecting observer gains is offered. An additional method for shaping the feedback loop using a filter is also developed. It is shown that this SMC prefilter is equivalent to a form of model reference hedging. A complete design procedure is given which takes advantage of the sliding mode boundary layer to recast the SMC as a linear control law. Frequency domain loop shaping is then used to design the sliding manifold. Finally, three aircraft applications are demonstrated. An F-18/HARV is used to demonstrate a SISO pitch rate tracking controller. It is also used to demonstrate a MIMO lateral-directional roll rate tracking controller. The last application is a full linear six degree-of-freedom advanced tailless fighter model. The observer-based SMC is seen to provide excellent tracking with superior robustness to parameter changes and actuator failures.

  5. Detection and size measurement of individual hemozoin nanocrystals in aquatic environment using a whispering gallery mode resonator

    CERN Document Server

    Kim, Woosung; Zhu, Jiangang; Faraz, Monifi; Coban, Cevayir; Yang, Lan; 10.1364/OE.20.029426

    2013-01-01

    We, for the first time, report the detection and the size measurement of single nanoparticles (i.e. polystyrene) in aquatic environment using mode splitting in a whispering gallery mode (WGM) optical resonator, namely a microtoroid resonator. Using this method we achieved detecting and measuring individual synthetic hemozoin nanocrystals, which are a hemoglobin degradation by-product of malarial parasites, dispersed in a solution or in air. The results of size measurement in solution and in air agree with each other and with those obtained using scanning electron microscope and dynamic light scattering. Moreover, we compare the sensing capabilities of the degenerate (single resonance) and non-degenerate (split mode, doublet) operation regimes of the WGM resonator.

  6. GMDD: a database of GMO detection methods

    Directory of Open Access Journals (Sweden)

    Guo Rong

    2008-06-01

    Full Text Available Abstract Background Since more than one hundred events of genetically modified organisms (GMOs have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. Results GMO Detection method Database (GMDD has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific, and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the information on endogenous genes, certified reference materials, reference molecules, and the validation status of developed methods is included in this database. Furthermore, registered users can also submit new detection methods and sequences to this database, and the newly submitted information will be released soon after being checked. Conclusion GMDD contains comprehensive information of GMO detection methods. The database will make the GMOs analysis much easier.

  7. GMDD: a database of GMO detection methods.

    Science.gov (United States)

    Dong, Wei; Yang, Litao; Shen, Kailin; Kim, Banghyun; Kleter, Gijs A; Marvin, Hans J P; Guo, Rong; Liang, Wanqi; Zhang, Dabing

    2008-06-04

    Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the information on endogenous genes, certified reference materials, reference molecules, and the validation status of developed methods is included in this database. Furthermore, registered users can also submit new detection methods and sequences to this database, and the newly submitted information will be released soon after being checked. GMDD contains comprehensive information of GMO detection methods. The database will make the GMOs analysis much easier.

  8. Comparison of five digital scintigraphic display modes. An ROC curve analysis of detection performance.

    Science.gov (United States)

    Goin, J E; Preston, D F; Gallagher, J H; Wegst, A V

    1983-01-01

    In the last decade diagnostic imaging departments, even those of moderate size, have experienced unprecedented growth. Much of this expansion can be attributed directly to technological developments, including systems for the acquisition of diagnostic images in digital format. In modern imaging departments, digital-based systems are quite common and are found across the specialities of nuclear medicine, ultrasound, transmission and emission computed tomography, and angiography. Nuclear magnetic resonance is the newest digital-based modality, and it appears destined to achieve its place in the diagnostic arsenal. These systems all have one trait in common, which is the topic of this paper. They offer the potential of increasing diagnostic accuracy by varying the methods used to process and display the acquired imaged data. We present the results of a nuclear medicine study designed to compare observer performance among five digital scintigraphic display modes. The observer's task was to detect artificially created lesions in brain scintigrams. Each mode is defined by a combination of an image processing function and a method of display. Using 40 trained observers, a receiver operating characteristic curve analysis was performed. The results support the use of color displays in nuclear medicine.

  9. Bioluminescent bioreporter integrated circuit detection methods

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Michael L.; Paulus, Michael J.; Sayler, Gary S.; Applegate, Bruce M.; Ripp, Steven A.

    2005-06-14

    Disclosed are monolithic bioelectronic devices comprising a bioreporter and an OASIC. These bioluminescent bioreporter integrated circuit are useful in detecting substances such as pollutants, explosives, and heavy-metals residing in inhospitable areas such as groundwater, industrial process vessels, and battlefields. Also disclosed are methods and apparatus for detection of particular analytes, including ammonia and estrogen compounds.

  10. Detecting sulphate aerosol geoengineering with different methods

    Science.gov (United States)

    Lo, Y. T. Eunice; Charlton-Perez, Andrew J.; Lott, Fraser C.; Highwood, Eleanor J.

    2016-12-01

    Sulphate aerosol injection has been widely discussed as a possible way to engineer future climate. Monitoring it would require detecting its effects amidst internal variability and in the presence of other external forcings. We investigate how the use of different detection methods and filtering techniques affects the detectability of sulphate aerosol geoengineering in annual-mean global-mean near-surface air temperature. This is done by assuming a future scenario that injects 5 Tg yr‑1 of sulphur dioxide into the stratosphere and cross-comparing simulations from 5 climate models. 64% of the studied comparisons would require 25 years or more for detection when no filter and the multi-variate method that has been extensively used for attributing climate change are used, while 66% of the same comparisons would require fewer than 10 years for detection using a trend-based filter. This highlights the high sensitivity of sulphate aerosol geoengineering detectability to the choice of filter. With the same trend-based filter but a non-stationary method, 80% of the comparisons would require fewer than 10 years for detection. This does not imply sulphate aerosol geoengineering should be deployed, but suggests that both detection methods could be used for monitoring geoengineering in global, annual mean temperature should it be needed.

  11. Theoretical and experimental investigation of multispectral photoacoustic osteoporosis detection method

    Science.gov (United States)

    Steinberg, Idan; Hershkovich, Hadas Sara; Gannot, Israel; Eyal, Avishay

    2014-03-01

    Osteoporosis is a widespread disorder, which has a catastrophic impact on patients lives and overwhelming related to healthcare costs. Recently, we proposed a multispectral photoacoustic technique for early detection of osteoporosis. Such technique has great advantages over pure ultrasonic or optical methods as it allows the deduction of both bone functionality from the bone absorption spectrum and bone resistance to fracture from the characteristics of the ultrasound propagation. We demonstrated the propagation of multiple acoustic modes in animal bones in-vitro. To further investigate the effects of multiple wavelength excitations and of induced osteoporosis on the PA signal a multispectral photoacoustic system is presented. The experimental investigation is based on measuring the interference of multiple acoustic modes. The performance of the system is evaluated and a simple two mode theoretical model is fitted to the measured phase signals. The results show that such PA technique is accurate and repeatable. Then a multiple wavelength excitation is tested. It is shown that the PA response due to different excitation wavelengths revels that absorption by the different bone constitutes has a profound effect on the mode generation. The PA response is measured in single wavelength before and after induced osteoporosis. Results show that induced osteoporosis alters the measured amplitude and phase in a consistent manner which allows the detection of the onset of osteoporosis. These results suggest that a complete characterization of the bone over a region of both acoustic and optical frequencies might be used as a powerful tool for in-vivo bone evaluation.

  12. Apparatus and methods for detecting chemical permeation

    Science.gov (United States)

    Vo-Dinh, Tuan

    1994-01-01

    Apparatus and methods for detecting the permeation of hazardous or toxic chemicals through protective clothing are disclosed. The hazardous or toxic chemicals of interest do not possess the spectral characteristic of luminescence. The apparatus and methods utilize a spectrochemical modification technique to detect the luminescence quenching of an indicator compound which upon permeation of the chemical through the protective clothing, the indicator is exposed to the chemical, thus indicating chemical permeation.

  13. New Eavesdropper Detection Method in Quantum Cryptograph

    Directory of Open Access Journals (Sweden)

    Cătălin Anghel

    2011-12-01

    Full Text Available ecurity of quantum cryptographic algorithms is one of the main research directions in quantum cryptography. Security growth of the quantum key distribution systems can be realized by detecting the eavesdropper quickly, precisely and without letting any secret information in the hands of the enemy. This paper proposes a new method, named QBTT, to detect the enemy who try to tap the communication channel. The QBTT method can be implemented in every type of quantum key distribution scheme.

  14. Diagnostic methods of a bladed disc mode shape evaluation used for shrouded blades in steam turbines

    Science.gov (United States)

    Strnad, Jaromir; Liska, Jindrich

    2015-11-01

    This paper deals with advanced methods for the evaluation of a bladed disc behavior in terms of the wheel vibration and blade service time consumption. These methods are developed as parts of the noncontact vibration monitoring system of the steam turbine shrouded blades. The proposed methods utilize the time-frequency processing (cross spectra) and the method using least squares to analyse the data from the optical and magnetoresistive sensors, which are mounted in the stator radially above the rotor blades. Fundamentally, the blade vibrations are detected during the blade passages under the sensors and the following signal processing, which covers also the proposed methods, leads to the estimation of the blade residual service life. The prototype system implementing above mentioned techniques was installed into the last stage of the new steam turbine (LP part). The methods for bladed disc mode shape evaluation were successfully verified on the signals, which were obtained during the commission operation of the turbine.

  15. A novel sensor of potassium ions based on mode-filtered light detection

    Institute of Scientific and Technical Information of China (English)

    Xiao Hong Zhao; Li Ping Yang; Suo Zhu Wu; Wen Ping Cheng; Shao Min Shuang; Chuan Dong

    2010-01-01

    A novel potassium ions sensor based on mode-filtered light detection was reported.The analyzer was consisting of an optical fiber immobilized with a dye of bromocresol green and a fused-silica capillary.It was found that mode-filtered light intensity decreased with the concentration of potassium ions and a linear detection range of 0.25-20 mmol/L(R2 = 0.9977)was obtained with a detection limit of 9 × 10-5 mol/L as well as fast response,good reproducibility and reversibility in the working concentration range.

  16. Detecting spatio-temporal modes in multivariate data by entropy field decomposition

    Science.gov (United States)

    Frank, Lawrence R.; Galinsky, Vitaly L.

    2016-09-01

    A new data analysis method that addresses a general problem of detecting spatio-temporal variations in multivariate data is presented. The method utilizes two recent and complimentary general approaches to data analysis, information field theory (IFT) and entropy spectrum pathways (ESPs). Both methods reformulate and incorporate Bayesian theory, thus use prior information to uncover underlying structure of the unknown signal. Unification of ESP and IFT creates an approach that is non-Gaussian and nonlinear by construction and is found to produce unique spatio-temporal modes of signal behavior that can be ranked according to their significance, from which space-time trajectories of parameter variations can be constructed and quantified. Two brief examples of real world applications of the theory to the analysis of data bearing completely different, unrelated nature, lacking any underlying similarity, are also presented. The first example provides an analysis of resting state functional magnetic resonance imaging data that allowed us to create an efficient and accurate computational method for assessing and categorizing brain activity. The second example demonstrates the potential of the method in the application to the analysis of a strong atmospheric storm circulation system during the complicated stage of tornado development and formation using data recorded by a mobile Doppler radar. Reference implementation of the method will be made available as a part of the QUEST toolkit that is currently under development at the Center for Scientific Computation in Imaging.

  17. Adaptive filtering of electroencephalogram signals using the empirical-modes method

    Science.gov (United States)

    Grubov, V. V.; Runnova, A. E.; Koronovskii, A. A.; Hramov, A. E.

    2017-07-01

    A new method for the removal of physiological artifacts in the experimental signals of human electroencephalograms (EEGs) has been developed. The method is based on decomposition of the signal in terms of empirical modes. The algorithm involves EEG signal decomposition in terms of empirical modes, searching for modes with artifacts, removing these modes, and restoration of the EEG signal. The method was tested on experimental data and showed high efficiency in the removal of various physiological artifacts in EEGs.

  18. Quantum metrology with two-mode squeezed thermal state: Parity detection and phase sensitivity

    Science.gov (United States)

    Li, Heng-Mei; Xu, Xue-Xiang; Yuan, Hong-Chun; Wang, Zhen

    2016-10-01

    Based on the Wigner-function method, we investigate the parity detection and phase sensitivity in a Mach-Zehnder interferometer (MZI) with two-mode squeezed thermal state (TMSTS). Using the classical transformation relation of the MZI, we derive the input-output Wigner functions and then obtain the explicit expressions of parity and phase sensitivity. The results from the numerical calculation show that supersensitivity can be reached only if the input TMSTS have a large number photons. Project supported by the National Natural Science Foundation of China (Grant No. 11447002), the Research Foundation of the Education Department of Jiangxi Province of China (Grant No. GJJ150338), and the Research Foundation for Changzhou Institute of Modern Optoelectronic Technology (Grant No. CZGY15).

  19. Biosensor for human IgE detection using shear-mode FBAR devices

    Science.gov (United States)

    Chen, Ying-Chung; Shih, Wei-Che; Chang, Wei-Tsai; Yang, Chun-Hung; Kao, Kuo-Sheng; Cheng, Chien-Chuan

    2015-02-01

    Film bulk acoustic resonators (FBARs) have been evaluated for use as biosensors because of their high sensitivity and small size. This study fabricated a novel human IgE biosensor using shear-mode FBAR devices with c-axis 23°-tilted AlN thin films. Off-axis radio frequency (RF) magnetron sputtering method was used for deposition of c-axis 23°-tilted AlN thin films. The deposition parameters were adopted as working pressure of 5 mTorr, substrate temperature of 300°C, sputtering power of 250 W, and 50 mm distance between off-axis and on-axis. The characteristics of the AlN thin films were investigated by X-ray diffraction and scanning electron microscopy. The frequency response was measured with an HP8720 network analyzer with a CASCADE probe station. The X-ray diffraction revealed (002) preferred wurtzite structure, and the cross-sectional image showed columnar structure with 23°-tilted AlN thin films. In the biosensor, an Au/Cr layer in the FBAR backside cavity was used as the detection layer and the Au surface was modified using self-assembly monolayers (SAMs) method. Then, the antigen and antibody were coated on biosensor through their high specificity property. Finally, the shear-mode FBAR device with k t 2 of 3.18% was obtained, and the average sensitivity for human IgE detection of about 1.425 × 105 cm2/g was achieved.

  20. Robust fault detection for discrete-time Markovian jump systems with mode-dependent time-delays

    Institute of Scientific and Technical Information of China (English)

    Hongru WANG; Changhong WANG; Shaoshuai MOU; Huijun GAO

    2007-01-01

    This paper investigates a fault detection problem for a class of discrete-time Markovian jump systems with norm-bounded uncertainties and mode-dependent time-delays. Attention is focused on constructing the residual generator based on the filter of which its parameters matrices are dependent on the system mode, that is, the fault detection filter is a Markovian jump system as well. The design of fault detection filter is reduced to H-infinity filtering problem by using H-infinity control theory, which can guarantee the difference between the residual and the fault (or, more generally weighted fault) as small as possible in the context of enhancing the robustness of residual to modeling errors, control inputs and unknown inputs. Sufficient condition for the existence of the above filters is established by means of linear matrix inequalities, which can be readily solved by using standard numerical software. A numerical example is given to illustrate the feasibility of the proposed method.

  1. Dual-transduction-mode sensing approach for chemical detection

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liang (Frank); Swensen, James S.

    2012-11-01

    Smart devices such as electronic nose have been developed for application in many fields like national security, defense, environmental regulation, health care, pipeline monitoring and food analysis. Despite a large array of individual sensors, these devices still lack the ability to identify a target at a very low concentration out of a mixture of odors, limited by a single type of transduction as the sensing response to distinguish one odor from another. Here, we propose a new sensor architecture empowering each individual sensor with multi-dimensional transduction signals. The resolving power of our proposed electronic nose is thereby multiplied by a set of different and independent variables which synergistically will provide a unique combined fingerprint for each analyte. We demonstrate this concept using a Light Emitting Organic Field-Effect Transistor (LEOFET). Sensing response has been observed on both electrical and optical output signals from a green LEOFET upon exposure to an explosive taggant, with optical signal exhibiting much higher sensitivity. This new sensor architecture opens a field of devices for smart detection of chemical and biological targets.

  2. Detection of North Atlantic Polar Lows in Climate Mode Simulations

    Science.gov (United States)

    Zahn, M.; von Storch, H.; Bakan, S.

    2007-12-01

    Polar lows are not properly resolved in global re-analyses. Atmospheric limited area models (LAMs), which post- process re-analysis data, may be an appropriate tool for describing the year-to-year variability and decadal trends in the formation of Polar Lows. The merits and potential of this approach are examined in case studies of reproducing polar low occurrences with a LAM. A series of three week long ensemble simulations of weather situations over the NE Atlantic with a RCM/LAM (CLM) was conducted and its capability to reproduce polar lows was investigated. To keep the influence of the initial field low, the simulations were begun approximately two weeks prior to the polar low formation. It is shown that polar lows can be reproduced with the LAM. When "spectral nudging" is applied a polar low develops in all ensemble members and the simulations are very insensitive to the initial conditions. However there are differences in detail compared to observational data, e.g extent of pressure decline and polar low's location. In a scond step towards our goal of determining trends in changing frequencies and characteristics, an algorithm for automatical detection polar lows has been designed and tested. This algorithm was applied to the output fields of a long-term simulation and first results are shown.

  3. Label-free bacteria detection using evanescent mode of a suspended core terahertz fiber

    CERN Document Server

    Mazhorova, Anna; Ng, Andy; Chinnappan, Raja; Zourob, Mohammed; Skorobogatiy, Maksim

    2011-01-01

    We propose for the first time an E. coli bacteria sensor based on the evanescent field of the fundamental mode of a suspended-core terahertz fiber. The sensor is capable of E. coli detection at concentrations in the range of 104-109 cfu/ml. The polyethylene fiber features a 150 {\\mu}m core suspended by three deeply sub-wavelength bridges in the center of a 5.1 mm-diameter cladding tube. The fiber core is biofunctionalized with T4 bacteriophages which bind and eventually destroy (lyse) their bacterial target. Using environmental SEM we demonstrate that E. coli is first captured by the phages on the fiber surface. After 25 minutes, most of the bacteria is infected by phages and then destroyed with ~1{\\mu}m-size fragments remaining bound to the fiber surface. The bacteria-binding and subsequent lysis unambiguously correlate with a strong increase of the fiber absorption. This signal allows the detection and quantification of bacteria concentration. Presented bacteria detection method is label-free and it does no...

  4. Edge Detection System using Pulse Mode Neural Network for Image Enhancement

    Directory of Open Access Journals (Sweden)

    S.Jagadeesh Babu

    2012-04-01

    Full Text Available Edge detection of an image reduces significantly the amount of data and filters out information that may be regarded as less irrelevant. Edge detection is efficient in medical imaging. Pulse mode neural networks are becoming an attractive solution for function approximation based on frequency modulation. Early pulse mode implementation suffers from some network constraints due to weight range limitations. To provide the best edge detection, the basic algorithm is modified to have pulse mode operations for effective hardware implementation. In this project a new pulse mode network architecture using floating point operations is used in the activation function. By using floating point number system for synapse weight value representation, any function can be approximated by the network. The proposed pulse mode MNN is used to detect the edges in images forming a heterogeneous data base. It shows good learning capability. In addition, four edge detection techniques have been compared. The coding is written in verilog and the final result have been simulated using Xilinx ISE simulator.

  5. A microfluidic based optical particle detection method

    Science.gov (United States)

    Dou, James; Chen, Lu; Nayyar, Rakesh; Aitchison, Stewart

    2012-03-01

    An optical particle detection and analysis method is presented. This method combines the capillary microfluidics, integrated optics and novel image acquisition and analysis algorithms to form the basis of a portable or handheld cytometer instrument. Experimental results provided shows the testing results are closely matched with conventional flow cytometer data.

  6. Travel Mode Detection Based on Neural Networks and Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Guangnian Xiao

    2015-08-01

    Full Text Available The collection of massive Global Positioning System (GPS data from travel surveys has increased exponentially worldwide since the 1990s. A number of methods, which range from rule-based to advanced classification approaches, have been applied to detect travel modes from GPS positioning data collected in travel surveys based on GPS-enabled smartphones or dedicated GPS devices. Among these approaches, neural networks (NNs are widely adopted because they can extract subtle information from training data that cannot be directly obtained by human or other analysis techniques. However, traditional NNs, which are generally trained by back-propagation algorithms, are likely to be trapped in local optimum. Therefore, particle swarm optimization (PSO is introduced to train the NNs. The resulting PSO-NNs are employed to distinguish among four travel modes (walk, bike, bus, and car with GPS positioning data collected through a smartphone-based travel survey. As a result, 95.81% of samples are correctly flagged for the training set, while 94.44% are correctly identified for the test set. Results from this study indicate that smartphone-based travel surveys provide an opportunity to supplement traditional travel surveys.

  7. SAR image change detection algorithm based on stationary wavelet and bi-dimensional intrinsic mode function

    Science.gov (United States)

    Huang, S. Q.; Wang, Z. L.; Xie, T. G.; Li, Z. C.

    2017-09-01

    Speckle noise in synthetic aperture radar (SAR) image is produced by the coherent imaging mechanism, which brings a great impact on the change information acquisition of multi-temporal SAR images. Two-dimensional stationary wavelet transform (SWT) and bi-dimensional empirical mode decomposition (BEMD) are the non-stationary signal processing theory of multi-scale transform. According to their implementation process and SAR image characteristic, this paper proposed a new multi-temporal SAR image change detection method based on the combination of the stationary wavelet transform and the bi-dimensional intrinsic mode function (BIMF) features, called SWT-BIMF algorithm. The contribution of the new algorithm includes two aspects. One is the design of the two selections of decomposition features, that is, the speckle noise filtering; another is the selected features to perform the enhance processing, so more effective change information will obtain. The feasibility of the SWT-BIMF algorithm is verified by the measured SAR image data, and good experimental results are obtained.

  8. On Analytical Methods in Neuroblastoma Detection

    Directory of Open Access Journals (Sweden)

    R. Martínez-Díaz

    2013-01-01

    quantitative and consistent methods of evaluation are needed to assess reponse to patient therapy. Whole-body I123-metaiodobenzylguanidine (mIBG scintigraphy is used as primary medical image modality to detect neuroblastoma tumours due to its high specificity and sensitivity. However, current oncological guidelines are based on qualitative observer-dependent analysis. This fact makes it difficult to compare results of scintigraphies taken at different moments during therapy or at different institutions. In this paper, we review analytical methods used in neuroblastoma detection and propose an observer-independent method to quantitatively analyse a I123-mIBG scintigraphy.

  9. An enhanced Monte Carlo outlier detection method.

    Science.gov (United States)

    Zhang, Liangxiao; Li, Peiwu; Mao, Jin; Ma, Fei; Ding, Xiaoxia; Zhang, Qi

    2015-09-30

    Outlier detection is crucial in building a highly predictive model. In this study, we proposed an enhanced Monte Carlo outlier detection method by establishing cross-prediction models based on determinate normal samples and analyzing the distribution of prediction errors individually for dubious samples. One simulated and three real datasets were used to illustrate and validate the performance of our method, and the results indicated that this method outperformed Monte Carlo outlier detection in outlier diagnosis. After these outliers were removed, the value of validation by Kovats retention indices and the root mean square error of prediction decreased from 3.195 to 1.655, and the average cross-validation prediction error decreased from 2.0341 to 1.2780. This method helps establish a good model by eliminating outliers. © 2015 Wiley Periodicals, Inc.

  10. Inner Crack Detection Method for Cantilever Beams

    Science.gov (United States)

    Li, Zheng; Zhang, Wei; Li, Yixuan; Su, Xianyue

    2008-02-01

    In this paper, continuous wavelet transform has been performed to extract the inner crack information from the guided waves in cantilever beams, and the location and size of crack can be detected exactly. Considering its best time-frequency property, Gabor continuous wavelet transform is employed to analyze the complicated flexible wave signals in cantilever beam, which is inspirited by an impact on the free end. Otherwise, in order to enhance the sensitivity of detection for some small cracks, an improved method is discussed. Here, both computational and experimental methods are carried out for comparing the influence of different crack location in beam. Therefore, the method proposed can be expected to expand to a powerful damage detection method in a broad engineering application.

  11. Differential cavity mode spectroscopy: A new cavity enhanced technique for the detection of weak transitions

    Energy Technology Data Exchange (ETDEWEB)

    Vine, Glenn de [Centre for Gravitational Physics, Faculty of Science, The Australian National University, Canberra ACT 0200 (Australia)], E-mail: glenn.devine@jpl.nasa.gov; McClelland, David E.; Gray, Malcolm B. [Centre for Gravitational Physics, Faculty of Science, The Australian National University, Canberra ACT 0200 (Australia)

    2008-06-16

    We present a new cavity enhanced, continuous wave spectroscopic technique for the detection of weak atomic and molecular transitions. Differential Cavity Mode Spectroscopy (DCMS) measures the difference in absorption between two adjacent cavity longitudinal modes to yield a highly sensitive, yet relatively simple, cavity enhanced spectroscopic technique. In addition this relative absorption measurement is, to first order, independent of both laser frequency noise and cavity acoustic noise. Here we present both a theoretical description of this new technique and an initial experimental demonstration.

  12. Modeling laser beam diffraction and propagation by the mode-expansion method.

    Science.gov (United States)

    Snyder, James J

    2007-08-01

    In the mode-expansion method for modeling propagation of a diffracted beam, the beam at the aperture can be expanded as a weighted set of orthogonal modes. The parameters of the expansion modes are chosen to maximize the weighting coefficient of the lowest-order mode. As the beam propagates, its field distribution can be reconstructed from the set of weighting coefficients and the Gouy phase of the lowest-order mode. We have developed a simple procedure to implement the mode-expansion method for propagation through an arbitrary ABCD matrix, and we have demonstrated that it is accurate in comparison with direct calculations of diffraction integrals and much faster.

  13. A Creative Method of Foreign Language Education: Integrated,Connected and Staged English Tesching Mode

    Institute of Scientific and Technical Information of China (English)

    FuJingyuan

    2004-01-01

    The uniqueness of Foreign Language Education is to unceasingly create new teaching methods and the purport of this paper is to explore an approach to a better English teaching mode -- Integrated, Connected and Staged English Teaching Mode.

  14. A method of detecting radio transients

    CERN Document Server

    Fridman, P A

    2010-01-01

    Radio transients are sporadic signals and their detection requires that the backends of radio telescopes be equipped with the appropriate hardware and software to undertake this. Observational programs to detect transients can be dedicated or they can piggy-back on observations made by other programs. It is the single-dish single-transient (non-periodical) mode which is considered in this paper. Because neither the width of a transient nor the time of its arrival is known, a sequential analysis in the form of a cumulative sum (cusum) algorithm is proposed here. Computer simulations and real observation data processing are included to demonstrate the performance of the cusum. The use of the Hough transform is here proposed for the purpose of non-coherent de-dispersion. It is possible that the detected transients could be radio frequency interferences (RFI) and a procedure is proposed here which can distinguish between celestial signals and man-made RFI. This procedure is based on an analysis of the statistical...

  15. Comparison of mode estimation methods and application in molecular clock analysis

    Science.gov (United States)

    Hedges, S. Blair; Shah, Prachi

    2003-01-01

    BACKGROUND: Distributions of time estimates in molecular clock studies are sometimes skewed or contain outliers. In those cases, the mode is a better estimator of the overall time of divergence than the mean or median. However, different methods are available for estimating the mode. We compared these methods in simulations to determine their strengths and weaknesses and further assessed their performance when applied to real data sets from a molecular clock study. RESULTS: We found that the half-range mode and robust parametric mode methods have a lower bias than other mode methods under a diversity of conditions. However, the half-range mode suffers from a relatively high variance and the robust parametric mode is more susceptible to bias by outliers. We determined that bootstrapping reduces the variance of both mode estimators. Application of the different methods to real data sets yielded results that were concordant with the simulations. CONCLUSION: Because the half-range mode is a simple and fast method, and produced less bias overall in our simulations, we recommend the bootstrapped version of it as a general-purpose mode estimator and suggest a bootstrap method for obtaining the standard error and 95% confidence interval of the mode.

  16. Novel methods for detecting buried explosive devices

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S.W.; Burlage, R.S.; Patek, D.R.; Smith, C.M. [Oak Ridge National Lab., TN (United States); Hibbs, A.D.; Rayner, T.J. [Quantum Magnetics, Inc., San Diego, CA (United States)

    1997-04-01

    Oak Ridge National Laboratory (ORNL) and Quantum Magnetics, Inc. (QM) are exploring novel landmine detection technologies. Technologies considered here include bioreporter bacteria, swept acoustic resonance, nuclear quadrupole resonance (NQR), and semiotic data fusion. Bioreporter bacteria look promising for third-world humanitarian applications; they are inexpensive, and deployment does not require high-tech methods. Swept acoustic resonance may be a useful adjunct to magnetometers in humanitarian demining. For military demining, NQR is a promising method for detecting explosive substances; of 50,000 substances that have been tested, none has an NQR signature that can be mistaken for RDX or TNT. For both military and commercial demining, sensor fusion entails two daunting tasks, identifying fusible features in both present-day and emerging technologies, and devising a fusion algorithm that runs in real-time on cheap hardware. Preliminary research in these areas is encouraging. A bioreporter bacterium for TNT detection is under development. Investigation has just started in swept acoustic resonance as an approach to a cheap mine detector for humanitarian use. Real-time wavelet processing appears to be a key to extending NQR bomb detection into mine detection, including TNT-based mines. Recent discoveries in semiotics may be the breakthrough that will lead to a robust fused detection scheme.

  17. Acquisition algorithm for direct-detection ladars with Geiger-mode avalanche photodiodes.

    Science.gov (United States)

    Milstein, Adam B; Jiang, Leaf A; Luu, Jane X; Hines, Eric L; Schultz, Kenneth I

    2008-01-10

    An optimal algorithm for detecting a target using a ladar system employing Geiger-mode avalanche photodiodes (GAPDs) is presented. The algorithm applies to any scenario where a ranging direct detection ladar is used to determine the presence of a target against a sky background within a specified range window. A complete statistical model of the detection process for GAPDs is presented, including GAPDs that are inactive for a fixed period of time each time they fire. The model is used to develop a constant false alarm rate detection algorithm that minimizes acquisition time. Numerical performance predictions, simulation results, and experimental results are presented.

  18. Label-free Detection of Protein Released during Platelet Activation by CNT-Enhanced Love Mode SAW Sensors.

    Science.gov (United States)

    Wu, Huiyan; Zu, Hongfei; Wang, Qing-Ming; Zhao, Gangyi; Wang, Jamesu H-C

    2014-09-01

    Platelet-rich plasma (PRP) has been applied in a series of clinical treatments. PRP contains high-concentrated platelets, which, when activated, could secret a variety of growth factors and cytokines, to promote and/or enhance healing of injured tissues. Non-activated platelets suspension could be prepared by an isolation method of centrifugation and washing currently. However, it is not clear whether platelets, if any, are already activated during this process and there is no simple method to monitor their activation accordingly. Shear-Horizontal Surface Acoustic Wave sensors (SH-SAW, Love Mode) are promising in fundamental biology as well as biomedical engineering, detecting cell behaviors in liquid in a non-invasive, simple and quantitative manner. In this study, Love mode sensors are adopted for the label-free detection of protein secreted by platelets. Carbon nanotube (CNT) is reported as an advisable platform of both non-specific protein adsorption and specific protein binding. For further improvement of Love mode sensor performance, novel CNT -coated parylene-C film is prepared on its surface as both the acoustic-wave-guiding layer and bio-interface layer. The S21 loss curves of Love mode sensors were recorded and the corresponding resonance frequencies were extracted. The results showed that the CNT-enhanced sensor possessed an increased resonance frequency shift when compared to normal sensor with single parylene-C film under identical collagen concentrations. Then, the modified sensor is used for label-free detection of protein released by various concentrations of platelets. The results revealed high sensitivity and consistency, indicating the potential of CNT-enhanced Love mode sensors in cell-based applications.

  19. Failure mode classification of reinforced concrete column using Fisher method

    Institute of Scientific and Technical Information of China (English)

    戚永乐; 韩小雷; 季静

    2013-01-01

    In order to apply the performance-based seismic design, an engineer must first find out whether the column is expected to fail in shear before or after flexural yielding. According to column failure characteristics and failure mode of reinforced concrete column, the UW-PEER structure performance database was discussed and analyzed. In order to investigate the relevance of failure mode and factors such as longitudinal reinforcement ratio, transverse reinforcement ratio, hoop spacing to depth ratio, aspect ratio, shearing resistance demand to shear capacity ratio and axial load ratio, Fisher’s discriminant analysis(FDA) of the above factors was carried out. A discriminant function was developed to identify column failure mode. Results show that three factors, i.e., Vp /Vn, hoop spacing to depth ratio and aspect ratio have important influence on the failure mode. The failure mode has less to do with longitudinal reinforcement ratio, transverse reinforcement ratio and axial load ratio. Through using these three factors and the model proposed, over 85.6% of the original grouped cases were correctly classified. The value of coefficient of Vp /Vn is the largest, which means that discriminant equation is most sensitive to the shearing resistance demand to shear capacity ratio.

  20. Method for the detection of aquaretic compounds

    DEFF Research Database (Denmark)

    2003-01-01

    Disclosed is a method for detecting an aquaretic compound. In one embodiment, the method includes administering to a mammal a candidate compound that modulates a nociceptin receptor. Biological material is isolated from the mammal and expression of aquaporin-2 is measured. Modulation of the aquap......Disclosed is a method for detecting an aquaretic compound. In one embodiment, the method includes administering to a mammal a candidate compound that modulates a nociceptin receptor. Biological material is isolated from the mammal and expression of aquaporin-2 is measured. Modulation...... of the aquaporin-2 is taken to be indicative of a candidate compound having aquaretic activity. The invention has a wide spectrum of uses including helping to identify new diuretics that spare unwanted loss of sodium and potassium ions....

  1. Flow cytometric detection method for DNA samples

    Energy Technology Data Exchange (ETDEWEB)

    Nasarabadi,Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Round Rock, TX)

    2011-07-05

    Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM.TM. on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA.TM., on the 5' end.

  2. Detecting Urban Transport Modes Using a Hybrid Knowledge Driven Framework from GPS Trajectory

    Directory of Open Access Journals (Sweden)

    Rahul Deb Das

    2016-11-01

    Full Text Available Transport mode information is essential for understanding people’s movement behavior and travel demand estimation. Current approaches extract travel information once the travel is complete. Such approaches are limited in terms of generating just-in-time information for a number of mobility based applications, e.g., real time mode specific patronage estimation. In order to detect the transport modalities from GPS trajectories, various machine learning approaches have already been explored. However, the majority of them produce only a single conclusion from a given set of evidences, ignoring the uncertainty of any mode classification. Also, the existing machine learning approaches fall short in explaining their reasoning scheme. In contrast, a fuzzy expert system can explain its reasoning scheme in a human readable format along with a provision of inferring different outcome possibilities, but lacks the adaptivity and learning ability of machine learning. In this paper, a novel hybrid knowledge driven framework is developed by integrating a fuzzy logic and a neural network to complement each other’s limitations. Thus the aim of this paper is to automate the tuning process in order to generate an intelligent hybrid model that can perform effectively in near-real time mode detection using GPS trajectory. Tests demonstrate that a hybrid knowledge driven model works better than a purely knowledge driven model and at per the machine learning models in the context of transport mode detection.

  3. A method for detecting hydrophobic patches protein

    NARCIS (Netherlands)

    Lijnzaad, P.; Berendsen, H.J.C.; Argos, P.

    1996-01-01

    A method for the detection of hydrophobic patches on the surfaces of protein tertiary structures is presented, it delineates explicit contiguous pieces of surface of arbitrary size and shape that consist solely of carbon and sulphur atoms using a dot representation of the solvent-accessible surface,

  4. GMDD: a database of GMO detection methods

    NARCIS (Netherlands)

    Dong, W.; Yang, L.; Shen, K.; Kim, B.; Kleter, G.A.; Marvin, H.J.P.; Guo, R.; Liang, W.; Zhang, D.

    2008-01-01

    Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been de

  5. GMDD: a database of GMO detection methods

    NARCIS (Netherlands)

    Dong, W.; Yang, L.; Shen, K.; Kim, B.; Kleter, G.A.; Marvin, H.J.P.; Guo, R.; Liang, W.; Zhang, D.

    2008-01-01

    Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been

  6. A method for detecting hydrophobic patches protein

    NARCIS (Netherlands)

    Lijnzaad, P.; Berendsen, H.J.C.; Argos, P.

    1996-01-01

    A method for the detection of hydrophobic patches on the surfaces of protein tertiary structures is presented, it delineates explicit contiguous pieces of surface of arbitrary size and shape that consist solely of carbon and sulphur atoms using a dot representation of the solvent-accessible surface,

  7. Selecting the pre-detection characteristics for fiber coupling of parametric down-converted biphoton modes

    Science.gov (United States)

    Anwar, Ali; Chithrabhanu, P.; Reddy, Salla Gangi; Lal, Nijil; Singh, R. P.

    2017-01-01

    Photon modes have an important role in characterizing the quantum sources of light. The two main pre-detection factors affecting the biphoton mode coupling in SPDC are the pump beam focusing parameter and the crystal thickness. We present the numerical and experimental results on the effect of pump focusing on conditional down-converted photon modes for a Type-I BBO crystal. We experimentally verify that biphoton coupling efficiency decreases asymptotically with pump beam focusing parameter. We attribute this behaviour to (a) the asymmetry in the spatial distribution of down-converted photons with the pump beam focusing parameter and (b) the ellipticity of biphoton modes introduced due to the focusing of the pump beam. We also show the ellipticity experimentally as well as quantify it with the focusing parameter. These results may be useful in selecting optimum conditions for generating efficient fiber coupled sources of heralded single photons and entangled photons for quantum information applications.

  8. Fused Empirical Mode Decomposition and MUSIC Algorithms for Detecting Multiple Combined Faults in Induction Motors

    Directory of Open Access Journals (Sweden)

    D. Camarena-Martinez

    2015-02-01

    Full Text Available Detection of failures in induction motors is one of the most important concerns in industry. An unexpected fault in the induction motors can cause a loss of financial resources and waste of time that most companies cannot afford. The contribution of this paper is a fusion of the Empirical Mode Decomposition (EMD and Multiple Signal Classification (MUSIC methodologies for detection of multiple combined faults which provides an accurate and effective strategy for the motor condition diagnosis.

  9. Mammography use and mode of detection among breast cancer patients in Estonia.

    Science.gov (United States)

    Innos, Kaire; Valvere, Vahur; Padrik, Peeter; Eelma, Evelyn; Kütner, Riina; Lehtsaar, Jaak; Tekkel, Mare

    2016-01-01

    The aim of this study was to examine past mammography use and mode of detection among breast cancer (BC) patients in Estonia, a country that has low screening coverage and high BC mortality. Women newly diagnosed with primary BC in Estonia in 2008-2010 were interviewed. Determinants of past mammography use and the detection of BC by mammography were studied using multivariate logistic regression. Among 977 participants, almost half reported no mammograms prior to the detection of BC. Overall, 22% of the cases were detected by mammography (16% by screening mammography). Detection by mammography was strongly related to age, past mammography use, and obesity. Among cases detected by mammography, 10% were stage III/IV at diagnosis (32% among cases detected by other modes). This study showed low mammography utilization and high rate of self-detection of BC in Estonia. Increased detection by mammography would help diagnose the disease at an earlier stage and consequently avoid premature BC deaths. Efforts should be undertaken to increase participation in screening and improve the availability of mammography among older and high-risk women. The results are likely to be relevant for other countries and population groups with low screening coverage.

  10. Motion Mode Recognition and Step Detection Algorithms for Mobile Phone Users

    Directory of Open Access Journals (Sweden)

    Gérard Lachapelle

    2013-01-01

    Full Text Available Microelectromechanical Systems (MEMS technology is playing a key role in the design of the new generation of smartphones. Thanks to their reduced size, reduced power consumption, MEMS sensors can be embedded in above mobile devices for increasing their functionalities. However, MEMS cannot allow accurate autonomous location without external updates, e.g., from GPS signals, since their signals are degraded by various errors. When these sensors are fixed on the user’s foot, the stance phases of the foot can easily be determined and periodic Zero velocity UPdaTes (ZUPTs are performed to bound the position error. When the sensor is in the hand, the situation becomes much more complex. First of all, the hand motion can be decoupled from the general motion of the user. Second, the characteristics of the inertial signals can differ depending on the carrying modes. Therefore, algorithms for characterizing the gait cycle of a pedestrian using a handheld device have been developed. A classifier able to detect motion modes typical for mobile phone users has been designed and implemented. According to the detected motion mode, adaptive step detection algorithms are applied. Success of the step detection process is found to be higher than 97% in all motion modes.

  11. Motion mode recognition and step detection algorithms for mobile phone users.

    Science.gov (United States)

    Susi, Melania; Renaudin, Valérie; Lachapelle, Gérard

    2013-01-24

    Microelectromechanical Systems (MEMS) technology is playing a key role in the design of the new generation of smartphones. Thanks to their reduced size, reduced power consumption, MEMS sensors can be embedded in above mobile devices for increasing their functionalities. However, MEMS cannot allow accurate autonomous location without external updates, e.g., from GPS signals, since their signals are degraded by various errors. When these sensors are fixed on the user's foot, the stance phases of the foot can easily be determined and periodic Zero velocity UPdaTes (ZUPTs) are performed to bound the position error. When the sensor is in the hand, the situation becomes much more complex. First of all, the hand motion can be decoupled from the general motion of the user. Second, the characteristics of the inertial signals can differ depending on the carrying modes. Therefore, algorithms for characterizing the gait cycle of a pedestrian using a handheld device have been developed. A classifier able to detect motion modes typical for mobile phone users has been designed and implemented. According to the detected motion mode, adaptive step detection algorithms are applied. Success of the step detection process is found to be higher than 97% in all motion modes.

  12. Innovative mode of action based in vitro assays for detection of marine neurotoxins

    NARCIS (Netherlands)

    Nicolas, J.A.Y.

    2015-01-01

    Innovative mode of action based in vitro assays for detection of marine neurotoxins J. Nicolas, P.J.M. Hendriksen, T.F.H. Bovee, I.M.C.M. Rietjens Marine biotoxins are naturally occurring compounds produced by particular phytoplankton species. These toxins often accumulate in seafood and thereby

  13. A quantitative method for Failure Mode and Effects Analysis

    NARCIS (Netherlands)

    Braaksma, A.J.J.; Meesters, A.J.; Klingenberg, W.; Hicks, C.

    2012-01-01

    Failure Mode and Effects Analysis (FMEA) is commonly used for designing maintenance routines by analysing potential failures, predicting their effect and facilitating preventive action. It is used to make decisions on operational and capital expenditure. The literature has reported that despite its

  14. Bayesian Methods for Radiation Detection and Dosimetry

    CERN Document Server

    Groer, Peter G

    2002-01-01

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed comp...

  15. Intrusion detection using pattern recognition methods

    Science.gov (United States)

    Jiang, Nan; Yu, Li

    2007-09-01

    Today, cyber attacks such as worms, scanning, active attackers are pervasive in Internet. A number of security approaches are proposed to address this problem, among which the intrusion detection system (IDS) appears to be one of the major and most effective solutions for defending against malicious users. Essentially, intrusion detection problem can be generalized as a classification problem, whose goal is to distinguish normal behaviors and anomalies. There are many well-known pattern recognition algorithms for classification purpose. In this paper we describe the details of applying pattern recognition methods to the intrusion detection research field. Experimenting on the KDDCUP 99 data set, we first use information gain metric to reduce the dimensionality of the original feature space. Two supervised methods, the support vector machine as well as the multi-layer neural network have been tested and the results display high detection rate and low false alarm rate, which is promising for real world applications. In addition, three unsupervised methods, Single-Linkage, K-Means, and CLIQUE, are also implemented and evaluated in the paper. The low computational complexity reveals their application in initial data reduction process.

  16. Constraining the r-mode saturation amplitude from a hypothetical detection of r-mode gravitational waves from a newborn neutron star - sensitivity study

    CERN Document Server

    Mytidis, Antonis; Whiting, Bernard

    2015-01-01

    This paper consists of two related parts: In the first part we derive an expression of the moment of inertia (MOI) of a neutron star as a function of observables from a hypothetical r-mode gravitational wave detection. For a given r-mode detection we show how the value of the MOI of a neutron star constrains the equation of state (EOS) of the matter in the core of the neutron star. Subsequently, for each candidate EOS, we derive a possible value of the saturation amplitude, \\alpha, of the r-mode oscillations on the neutron star. Additionally, we argue that a r-mode detection will provide clues about the cooling rate mechanism of the neutron star. The above physics that can be derived from a hypothetical r-mode detection constitute our motivation for the second part of the paper. In that part we present a detection strategy to efficiently search for r-modes in gravitational-wave data. R-mode signals were injected into simulated noise colored with the advanced LIGO (aLIGO) and Einstein Telescope (ET) sensitivit...

  17. Drag detection and identification by whispering gallery mode optical resonance based sensor

    Science.gov (United States)

    Saetchnikov, Vladimir A.; Tcherniavskaia, Elina A.; Saetchnikov, Anton V.; Schweiger, Gustav; Ostendorf, Andreas

    2013-06-01

    Experimental data on optical resonance spectra of whispering gallery modes of dielectric microspheres in antibiotic solutions under varied in wide range concentration are represented. Optical resonance was demonstrated could be detected at a laser power of less than 1 microwatt. Several antibiotics of different generations: Amoxicillin, Azithromycin, Cephazolin, Chloramphenicol, Levofloxacin, Lincomicin Benzylpenicillin, Riphampicon both in deionized water and physiological solution had been used for measurements. Both spectral shift and the structure of resonance spectra were of specific interest in this investigation. Drag identification has been performed by developed multilayer perceptron network. The network topology was designed included: a number of the hidden layers of multilayered perceptron, a number of neurons in each of layers, a method of training of a neural network, activation functions of layers, type and size of a deviation of the received values from required values. For a network training the method of the back propagation error in various modifications has been used. Input vectors correspond to 6 classes of biological substances under investigation. The result of classification was considered as positive when each of the region, representing a certain substance in a space: relative spectral shift of an optical resonance maxima - relative efficiency of excitation of WGM, was singly connected. It was demonstrated that the approach described in the paper can be a promising platform for the development of sensitive, lab-on-chip type sensors that can be used as an express diagnostic tools for different drugs and instrumentation for proteomics, genomics, drug discovery, and membrane studies.

  18. A novel method for detection of apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Zagariya, Alexander M., E-mail: zagariya@uic.edu

    2012-04-15

    There are two different Angiotensin II (ANG II) peptides in nature: Human type (ANG II) and Bovine type (ANG II*). These eight amino acid peptides differ only at position 5 where Valine is replaced by Isoleucine in the Bovine type. They are present in all species studied so far. These amino acids are different by only one atom of carbon. This difference is so small, that it will allow any of ANG II, Bovine or Human antibodies to interact with all species and create a universal method for apoptosis detection. ANG II concentrations are found at substantially higher levels in apoptotic, compared to non-apoptotic, tissues. ANG II accumulation can lead to DNA damage, mutations, carcinogenesis and cell death. We demonstrate that Bovine antiserum can be used for universal detection of apoptosis. In 2010, the worldwide market for apoptosis detection reached the $20 billion mark and significantly increases each year. Most commercially available methods are related to Annexin V and TUNNEL. Our new method based on ANG II is more widely known to physicians and scientists compared to previously used methods. Our approach offers a novel alternative for assessing apoptosis activity with enhanced sensitivity, at a lower cost and ease of use.

  19. Need for new caries detection methods

    Science.gov (United States)

    Young, Douglas A.; Featherstone, John D. B.

    1999-05-01

    Dental caries (tooth decay) continues to be a major problems for adults as well as children, even though great advances have been made in preventive methods in the last 20 years. New methods for the management of caries will work best if lesions can be detected at an early stage and chemical rather than physical intervention can take place, thereby preserving the natural tooth structure and helping the saliva to heal, or remineralize, the areas of early decay. Clinical detection of caries in the US relies on visual examination, tactile with hand held explorer, and conventional radiographs, all of which are inadequate for the occlusal (biting) surfaces of the teeth where most of the decay now occurs. The dentist often has to explore by drilling with a dental bur to confirm early decay in these areas. New method that can determine the extent and degree of subsurface lesions in these surfaces non-destructively are essential for further advances in the clinical management of dental caries. Optical methods, which exploit the differences between sound and carious enamel and dentin, show great promise for the accurate detection of these lesions. Two or three- dimensional images, which include a measure of severity will be needed.

  20. Molecular methods for the detection of mutations.

    Science.gov (United States)

    Monteiro, C; Marcelino, L A; Conde, A R; Saraiva, C; Giphart-Gassler, M; De Nooij-van Dalen, A G; Van Buuren-van Seggelen, V; Van der Keur, M; May, C A; Cole, J; Lehmann, A R; Steinsgrimsdottir, H; Beare, D; Capulas, E; Armour, J A

    2000-01-01

    We report the results of a collaborative study aimed at developing reliable, direct assays for mutation in human cells. The project used common lymphoblastoid cell lines, both with and without mutagen treatment, as a shared resource to validate the development of new molecular methods for the detection of low-level mutations in the presence of a large excess of normal alleles. As the "gold standard, " hprt mutation frequencies were also measured on the same samples. The methods under development included i) the restriction site mutation (RSM) assay, in which mutations lead to the destruction of a restriction site; ii) minisatellite length-change mutation, in which mutations lead to alleles containing new numbers of tandem repeat units; iii) loss of heterozygosity for HLA epitopes, in which antibodies can be used to direct selection for mutant cells; iv) multiple fluorescence-based long linker arm nucleotides assay (mf-LLA) technology, for the detection of substitutional mutations; v) detection of alterations in the TP53 locus using a (CA) array as the target for the screening; and vi) PCR analysis of lymphocytes for the presence of the BCL2 t(14:18) translocation. The relative merits of these molecular methods are discussed, and a comparison made with more "traditional" methods.

  1. Relevant modes selection method based on Spearman correlation coefficient for laser signal denoising using empirical mode decomposition

    Science.gov (United States)

    Duan, Yabo; Song, Chengtian

    2016-10-01

    Empirical mode decomposition (EMD) is a recently proposed nonlinear and nonstationary laser signal denoising method. A noisy signal is broken down using EMD into oscillatory components that are called intrinsic mode functions (IMFs). Thresholding-based denoising and correlation-based partial reconstruction of IMFs are the two main research directions for EMD-based denoising. Similar to other decomposition-based denoising approaches, EMD-based denoising methods require a reliable threshold to determine which IMFs are noise components and which IMFs are noise-free components. In this work, we propose a new approach in which each IMF is first denoised using EMD interval thresholding (EMD-IT), and then a robust thresholding process based on Spearman correlation coefficient is used for relevant modes selection. The proposed method tackles the problem using a thresholding-based denoising approach coupled with partial reconstruction of the relevant IMFs. Other traditional denoising methods, including correlation-based EMD partial reconstruction (EMD-Correlation), discrete Fourier transform and wavelet-based methods, are investigated to provide a comparison with the proposed technique. Simulation and test results demonstrate the superior performance of the proposed method when compared with the other methods.

  2. Relevant modes selection method based on Spearman correlation coefficient for laser signal denoising using empirical mode decomposition

    Science.gov (United States)

    Duan, Yabo; Song, Chengtian

    2016-12-01

    Empirical mode decomposition (EMD) is a recently proposed nonlinear and nonstationary laser signal denoising method. A noisy signal is broken down using EMD into oscillatory components that are called intrinsic mode functions (IMFs). Thresholding-based denoising and correlation-based partial reconstruction of IMFs are the two main research directions for EMD-based denoising. Similar to other decomposition-based denoising approaches, EMD-based denoising methods require a reliable threshold to determine which IMFs are noise components and which IMFs are noise-free components. In this work, we propose a new approach in which each IMF is first denoised using EMD interval thresholding (EMD-IT), and then a robust thresholding process based on Spearman correlation coefficient is used for relevant modes selection. The proposed method tackles the problem using a thresholding-based denoising approach coupled with partial reconstruction of the relevant IMFs. Other traditional denoising methods, including correlation-based EMD partial reconstruction (EMD-Correlation), discrete Fourier transform and wavelet-based methods, are investigated to provide a comparison with the proposed technique. Simulation and test results demonstrate the superior performance of the proposed method when compared with the other methods.

  3. On-line methods for rotorcraft aeroelastic mode identification

    Science.gov (United States)

    Molusis, J. A.; Kleinman, D. L.

    1982-01-01

    The requirements for the on-line identification of rotorcraft aeroelastic blade modes from random response test data are presented. A recursive maximum likelihood (RML) technique is used in conjunction with a bandpass filter to identify isolated blade mode damping and frequency. The RML technique is demonstrated to have excellent convergence characteristics in random measurement noise and random process noise excitation. The RML identification technique uses an ARMA representation for the aeroelastic stochastic system and requires virtually no user interaction while providing accurate confidence bands on the parameter estimates. Comparisons are made with an off-line Newton type maximum likelihood algorithm which uses a state variable model representation. Results are presented from simulation random response data which quantify the identifed parameter convergence behavior for various levels of random excitation which is typical of wind tunnel turbulence levels. The RML technique is applied to hingless rotor test data from the NASA Langley Research Center Helicopter Hover Facility.

  4. Zero modes method and form factors in quantum integrable models

    Directory of Open Access Journals (Sweden)

    S. Pakuliak

    2015-04-01

    Full Text Available We study integrable models solvable by the nested algebraic Bethe ansatz and possessing GL(3-invariant R-matrix. Assuming that the monodromy matrix of the model can be expanded into series with respect to the inverse spectral parameter, we define zero modes of the monodromy matrix entries as the first nontrivial coefficients of this series. Using these zero modes we establish new relations between form factors of the elements of the monodromy matrix. We prove that all of them can be obtained from the form factor of a diagonal matrix element in special limits of Bethe parameters. As a result we obtain determinant representations for form factors of all the entries of the monodromy matrix.

  5. Chemical detection system and related methods

    Energy Technology Data Exchange (ETDEWEB)

    Caffrey, Augustine J.; Chichester, David L.; Egger, Ann E.; Krebs, Kenneth M.; Seabury, Edward H.; Van Siclen, Clinton D.; Wharton, C. Jayson; Zabriskie, John M.

    2017-06-27

    A chemical detection system includes a frame, an emitter coupled to the frame, and a detector coupled to the frame proximate the emitter. The system also includes a shielding system coupled to the frame and positioned at least partially between the emitter and the detector, wherein the frame positions a sensing surface of the detector in a direction substantially parallel to a plane extending along a front portion of the frame. A method of analyzing composition of a suspect object includes directing neutrons at the object, detecting gamma rays emitted from the object, and communicating spectrometer information regarding the gamma rays. The method also includes presenting a GUI to a user with a dynamic status of an ongoing neutron spectroscopy process. The dynamic status includes a present confidence for a plurality of compounds being present in the suspect object responsive to changes in the spectrometer information during the ongoing process.

  6. Computer Vision Method in Human Motion Detection

    Institute of Scientific and Technical Information of China (English)

    FU Li; FANG Shuai; XU Xin-he

    2007-01-01

    Human motion detection based on computer vision is a frontier research topic and is causing an increasing attention in the field of computer vision research. The wavelet transform is used to sharpen the ambiguous edges in human motion image. The shadow's effect to the image processing is also removed. The edge extraction can be successfully realized.This is an effective method for the research of human motion analysis system.

  7. NEW WIND-INDUCED RESPONSES ANALYSIS METHOD OF SPATIAL STRUCTURES IN FREQUENCY DOMAIN WITH MODE COMPENSATION

    Institute of Scientific and Technical Information of China (English)

    何艳丽; 董石麟

    2002-01-01

    Large span spatial lattice structures have many natural frequencies in a narrow frequency range, the conventional frequency domain method is difficult to contain all significant contribution modes. Through numerical examples, it is found that some high order modes are likely to be overlooked because of their higher positions of modal order, in spite of their significance to wind response. According to the contributions of modes to strain energy of system, the paper presented an efficient method to compensate the errors owing to missing out some significant high order modes. The effectiveness of the proposed method is verified through a numerical analysis of the wind responses of a spherical dome.

  8. Improved method for detection of starch hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Ohawale, M.R.; Wilson, J.J.; Khachatourians, G.G.; Ingledew, W.M.

    1982-09-01

    A new starch hydrolysis detection method which does not rely on iodine staining or the use of color-complexed starch is described. A linear relationship was obtained with agar-starch plates when net clearing zones around colonies of yeasts were plotted against enzyme levels (semilogarithm scale) produced by the same yeast strains in liquid medium. A similar relationship between starch clearing zones and alpha-amylase levels from three different sources was observed. These observations suggest that the method is useful in mutant isolations, strain improvement programs, and the prediction of alpha-amylase activities in culture filtrates or column effluents. (Refs. 18).

  9. Improved method for detection of starch hydrolysis.

    Science.gov (United States)

    Dhawale, M R; Wilson, J J; Khachatourians, G G; Ingledew, W M

    1982-09-01

    A new starch hydrolysis detection method which does not rely on iodine staining or the use of color-complexed starch is described. A linear relationship was obtained with agar-starch plates when net clearing zones around colonies of yeasts were plotted against enzyme levels (semilogarithm scale) produced by the same yeast strains in liquid medium. A similar relationship between starch clearing zones and alpha-amylase levels from three different sources was observed. These observations suggest that the method is useful in mutant isolations, strain improvement programs, and the prediction of alpha-amylase activities in culture filtrates or column effluents.

  10. Waterborne Pathogens: Detection Methods and Challenges

    Directory of Open Access Journals (Sweden)

    Flor Yazmín Ramírez-Castillo

    2015-05-01

    Full Text Available Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems’ infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health.

  11. Waterborne Pathogens: Detection Methods and Challenges

    Science.gov (United States)

    Ramírez-Castillo, Flor Yazmín; Loera-Muro, Abraham; Jacques, Mario; Garneau, Philippe; Avelar-González, Francisco Javier; Harel, Josée; Guerrero-Barrera, Alma Lilián

    2015-01-01

    Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems’ infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA) is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health. PMID:26011827

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

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Hiromichi; Kinoshita, Izumi [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab

    2001-04-01

    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)

  13. A method for extracting human gait series from accelerometer signals based on the ensemble empirical mode decomposition

    Science.gov (United States)

    Fu, Mao-Jing; Zhuang, Jian-Jun; Hou, Feng-Zhen; Zhan, Qing-Bo; Shao, Yi; Ning, Xin-Bao

    2010-05-01

    In this paper, the ensemble empirical mode decomposition (EEMD) is applied to analyse accelerometer signals collected during normal human walking. First, the self-adaptive feature of EEMD is utilised to decompose the accelerometer signals, thus sifting out several intrinsic mode functions (IMFs) at disparate scales. Then, gait series can be extracted through peak detection from the eigen IMF that best represents gait rhythmicity. Compared with the method based on the empirical mode decomposition (EMD), the EEMD-based method has the following advantages: it remarkably improves the detection rate of peak values hidden in the original accelerometer signal, even when the signal is severely contaminated by the intermittent noises; this method effectively prevents the phenomenon of mode mixing found in the process of EMD. And a reasonable selection of parameters for the stop-filtering criteria can improve the calculation speed of the EEMD-based method. Meanwhile, the endpoint effect can be suppressed by using the auto regressive and moving average model to extend a short-time series in dual directions. The results suggest that EEMD is a powerful tool for extraction of gait rhythmicity and it also provides valuable clues for extracting eigen rhythm of other physiological signals.

  14. A new method for FMRI activation detection

    Science.gov (United States)

    Wei, Jianing; Talavage, Thomas M.; Pollak, Ilya

    2009-02-01

    The objective of fMRI data analysis is to detect the region of the brain that gets activated in response to a specific stimulus presented to the subject. We develop a new algorithm for activation detection in event-related fMRI data. We utilize a forward model for fMRI data acquisition which explicitly incorporates physiological noise, scanner noise and the spatial blurring introduced by the scanner. After slice-by-slice image restoration procedure that independently restores each data slice corresponding to each time index, we estimate the parameters of the hemodynamic response function (HRF) model for each pixel of the restored data. In order to enforce spatial regularity in our estimates, we model the prior distribution of the HRF parameters as a generalized Gaussian Markov random field (GGMRF) model. We develop an algorithm to compute the maximum a posteriori (MAP) estimates of the parameters. We then threshold the amplitude parameters to obtain the final activation map. We illustrate our algorithm by comparing it with the widely used general linear model (GLM) method. In synthetic data experiments, under the same probability of false alarm, the probability of correct detection for our method is up to 15% higher than GLM. In real data experiments, through anatomical analysis and benchmark testing using block paradigm results, we demonstrate that our algorithm produces fewer false alarms than GLM.

  15. Nonlinear mode decomposition: A noise-robust, adaptive decomposition method

    Science.gov (United States)

    Iatsenko, Dmytro; McClintock, Peter V. E.; Stefanovska, Aneta

    2015-09-01

    The signals emanating from complex systems are usually composed of a mixture of different oscillations which, for a reliable analysis, should be separated from each other and from the inevitable background of noise. Here we introduce an adaptive decomposition tool—nonlinear mode decomposition (NMD)—which decomposes a given signal into a set of physically meaningful oscillations for any wave form, simultaneously removing the noise. NMD is based on the powerful combination of time-frequency analysis techniques—which, together with the adaptive choice of their parameters, make it extremely noise robust—and surrogate data tests used to identify interdependent oscillations and to distinguish deterministic from random activity. We illustrate the application of NMD to both simulated and real signals and demonstrate its qualitative and quantitative superiority over other approaches, such as (ensemble) empirical mode decomposition, Karhunen-Loève expansion, and independent component analysis. We point out that NMD is likely to be applicable and useful in many different areas of research, such as geophysics, finance, and the life sciences. The necessary matlab codes for running NMD are freely available for download.

  16. Nonlinear mode decomposition: a noise-robust, adaptive decomposition method.

    Science.gov (United States)

    Iatsenko, Dmytro; McClintock, Peter V E; Stefanovska, Aneta

    2015-09-01

    The signals emanating from complex systems are usually composed of a mixture of different oscillations which, for a reliable analysis, should be separated from each other and from the inevitable background of noise. Here we introduce an adaptive decomposition tool-nonlinear mode decomposition (NMD)-which decomposes a given signal into a set of physically meaningful oscillations for any wave form, simultaneously removing the noise. NMD is based on the powerful combination of time-frequency analysis techniques-which, together with the adaptive choice of their parameters, make it extremely noise robust-and surrogate data tests used to identify interdependent oscillations and to distinguish deterministic from random activity. We illustrate the application of NMD to both simulated and real signals and demonstrate its qualitative and quantitative superiority over other approaches, such as (ensemble) empirical mode decomposition, Karhunen-Loève expansion, and independent component analysis. We point out that NMD is likely to be applicable and useful in many different areas of research, such as geophysics, finance, and the life sciences. The necessary matlab codes for running NMD are freely available for download.

  17. Critical comparison of three modal methods: bidirectional eigenmode expansion propagation method, aperiodic rigorous coupled mode analysis, and harmonic expansion method

    Science.gov (United States)

    Ctyroký, Jirí; Richter, Ivan; Kwiecien, Pavel

    2008-06-01

    The performance of three bidirectional modal methods the "classical" bidirectional eigenmode expansion propagation method, the aperiodic rigorous coupled wave analysis (known also as the Fourier modal method), and the mode expansion method based on harmonic expansion are mutually compared using modeling tasks that include eigenmode calculation of a relatively high-contrast planar waveguide, spectral transmittance of a one-dimensional "photonic crystal" filter in a photonic wire, spectral transmittance of a surface plasmon based optical sensor, and a reflectance from a double-groove structure in a high-contrast waveguide. All methods exhibit generally comparable performance, as follows from good mutual agreement of the results and generally comparable computational time. Although all methods use perfectly matched layers as absorbing boundary conditions, their implementation in the aperiodic rigorous coupled wave analysis exhibits significantly stronger attenuation than that used in the other two methods. Thus, significant improvement of the latter methods seems possible.

  18. An economic analysis of developmental detection methods.

    Science.gov (United States)

    Glascoe, F P; Foster, E M; Wolraich, M L

    1997-06-01

    To assess the costs and benefits of various approaches to early detection of developmental disabilities. Cost-benefit analyses based on data from previously published studies of developmental screening tests. General pediatric practices and day care centers. A total of 247 parents and their 0- to 6-year-old children-103 from day care centers and 144 from pediatric practices. Licensed psychological examiners administered a screening test of parents' concerns about children's development and one or two direct screening tests: the Denver-II and/or the Battelle Developmental Inventory Screening Test. For the day care sample, examiners also administered to each child measures of intelligence, adaptive behavior, and language. In the pediatric sample, children were administered additional assessments. At the same time, diagnostic measures were administered to a randomly selected subsample to make determinations about developmental status. Each screening method was evaluated for its short-term costs (administration, interpretation, diagnosis, and treatment) and long-term benefits (impact of early intervention on adult functioning as inferred from longitudinal studies by other researchers). When the long-term costs and benefits were considered, none of the approaches emerged as markedly superior to another. When viewing the short-term costs, the various screening approaches differed markedly. The use of parents' concerns was by far the least costly for physicians to administer and interpret. Physicians can incur tremendous expenses when attempting to detect children with developmental problems. Although the benefits of early detection and intervention are substantial, physicians are not well-compensated for providing a critical service to society. Health policymakers and third-party payers must reconsider their minimal investment in early detection by health care providers. Nevertheless, our findings have encouraging implications for practice, because the use of parents

  19. REFINED METHOD OF COMPUTING MODES OF OPERATING OF CAPACITY-TYPE SOLAR HEATERS OF

    Directory of Open Access Journals (Sweden)

    Ermuratschii Vl.V.

    2008-04-01

    Full Text Available The refined method procedure of thermal modes of solar heaters of water of the capacity type, based on use of an electro-thermal equivalent circuit and a method of central potentials is presented.

  20. Casimir Energy for a Purely Dielectric Cylinder by the Mode Summation Method

    CERN Document Server

    Romeo, A; Romeo, August; Milton, Kimball A.

    2005-01-01

    We use the mode summation method together with zeta-function regularization to compute the Casimir energy of a dilute dielectric cylinder. The method is very transparent, and sheds light on the reason the resulting energy vanishes.

  1. An electromagnetic induction method for underground target detection and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Bartel, L.C.; Cress, D.H.

    1997-01-01

    An improved capability for subsurface structure detection is needed to support military and nonproliferation requirements for inspection and for surveillance of activities of threatening nations. As part of the DOE/NN-20 program to apply geophysical methods to detect and characterize underground facilities, Sandia National Laboratories (SNL) initiated an electromagnetic induction (EMI) project to evaluate low frequency electromagnetic (EM) techniques for subsurface structure detection. Low frequency, in this case, extended from kilohertz to hundreds of kilohertz. An EMI survey procedure had already been developed for borehole imaging of coal seams and had successfully been applied in a surface mode to detect a drug smuggling tunnel. The SNL project has focused on building upon the success of that procedure and applying it to surface and low altitude airborne platforms. Part of SNL`s work has focused on improving that technology through improved hardware and data processing. The improved hardware development has been performed utilizing Laboratory Directed Research and Development (LDRD) funding. In addition, SNL`s effort focused on: (1) improvements in modeling of the basic geophysics of the illuminating electromagnetic field and its coupling to the underground target (partially funded using LDRD funds) and (2) development of techniques for phase-based and multi-frequency processing and spatial processing to support subsurface target detection and characterization. The products of this project are: (1) an evaluation of an improved EM gradiometer, (2) an improved gradiometer concept for possible future development, (3) an improved modeling capability, (4) demonstration of an EM wave migration method for target recognition, and a demonstration that the technology is capable of detecting targets to depths exceeding 25 meters.

  2. An electromagnetic induction method for underground target detection and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Bartel, L.C.; Cress, D.H.

    1997-01-01

    An improved capability for subsurface structure detection is needed to support military and nonproliferation requirements for inspection and for surveillance of activities of threatening nations. As part of the DOE/NN-20 program to apply geophysical methods to detect and characterize underground facilities, Sandia National Laboratories (SNL) initiated an electromagnetic induction (EMI) project to evaluate low frequency electromagnetic (EM) techniques for subsurface structure detection. Low frequency, in this case, extended from kilohertz to hundreds of kilohertz. An EMI survey procedure had already been developed for borehole imaging of coal seams and had successfully been applied in a surface mode to detect a drug smuggling tunnel. The SNL project has focused on building upon the success of that procedure and applying it to surface and low altitude airborne platforms. Part of SNL`s work has focused on improving that technology through improved hardware and data processing. The improved hardware development has been performed utilizing Laboratory Directed Research and Development (LDRD) funding. In addition, SNL`s effort focused on: (1) improvements in modeling of the basic geophysics of the illuminating electromagnetic field and its coupling to the underground target (partially funded using LDRD funds) and (2) development of techniques for phase-based and multi-frequency processing and spatial processing to support subsurface target detection and characterization. The products of this project are: (1) an evaluation of an improved EM gradiometer, (2) an improved gradiometer concept for possible future development, (3) an improved modeling capability, (4) demonstration of an EM wave migration method for target recognition, and a demonstration that the technology is capable of detecting targets to depths exceeding 25 meters.

  3. Dual Mode Sensing with Low-Profile Piezoelectric Thin Wafer Sensors for Steel Bridge Crack Detection and Diagnosis

    Directory of Open Access Journals (Sweden)

    Lingyu Yu

    2012-01-01

    Full Text Available Monitoring of fatigue cracking in steel bridges is of high interest to many bridge owners and agencies. Due to the variety of deterioration sources and locations of bridge defects, there is currently no single method that can detect and address the potential sources globally. In this paper, we presented a dual mode sensing methodology integrating acoustic emission and ultrasonic wave inspection based on the use of low-profile piezoelectric wafer active sensors (PWAS. After introducing the research background and piezoelectric sensing principles, PWAS crack detection in passive acoustic emission mode is first presented. Their acoustic emission detection capability has been validated through both static and compact tension fatigue tests. With the use of coaxial cable wiring, PWAS AE signal quality has been improved. The active ultrasonic inspection is conducted by the damage index and wave imaging approach. The results in the paper show that such an integration of passive acoustic emission detection with active ultrasonic sensing is a technological leap forward from the current practice of periodic and subjective visual inspection and bridge management based primarily on history of past performance.

  4. PRIMARY SIDE DETECTION AND PEAK CURRENT MODE CONTROL IN FLYBACK CONVERTER

    Institute of Scientific and Technical Information of China (English)

    Fang Jian; Lu Zhiping; Yang Jian; Li Zhaoji

    2004-01-01

    A new cycle-by-cycle control flyback converter with primary side detection and peak current mode control is proposed and its dynamic characteristics are analyzed. The flyback converter is verified by the OrCAD simulator. The main advantages of this converter over the conventional one are simplicity, small size, rapid regulating and no sensing control signals over the isolation barrier. The circuit is suitable for digital control implementations.

  5. Method and apparatus for detecting explosives

    Science.gov (United States)

    Moore, David Steven [Santa Fe, NM

    2011-05-10

    A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

  6. Detection methods for centrifugal microfluidic platforms

    DEFF Research Database (Denmark)

    Burger, Robert; Amato, Letizia; Boisen, Anja

    2016-01-01

    Centrifugal microfluidics has attracted much interest from academia as well as industry, since it potentially offers solutions for affordable, user-friendly and portable biosensing. A wide range of so-called fluidic unit operations, e.g. mixing, metering, liquid routing, and particle separation......, have been developed and allow automation and integration of complex assay protocols in lab-on-a-disc systems. Besides liquid handling, the detection strategy for reading out the assay is crucial for developing a fully integrated system. In this review, we focus on biosensors and readout methods...

  7. Detectability of f-mode Unstable Neutron Stars by the Schenberg Spherical Antenna

    CERN Document Server

    de Araujo, J C N; Aguiar, O D

    2005-01-01

    The Brazilian spherical antenna (Schenberg) is planned to detect high frequency gravitational waves (GWs) ranging from 3.0 kHz to 3.4 kHz. There is a host of astrophysical sources capable of being detected by the Brazilian antenna, namely: core collapse in supernova events; (proto)neutron stars undergoing hydrodynamical instability; f-mode unstable neutron stars, caused by quakes and oscillations; excitation of the first quadrupole normal mode of 4-9 solar mass black holes; coalescence of neutron stars and/or black holes; exotic sources such as bosonic or strange matter stars rotating at 1.6 kHz; and inspiralling of mini black hole binaries. We here address our study in particular to the neutron stars, which could well become f-mode unstable producing therefore GWs. We estimate, for this particular source of GWs, the event rates that in principle can be detected by Schenberg and by the Dutch Mini-Grail antenna.

  8. TLC bioautographic method for detecting lipase inhibitors.

    Science.gov (United States)

    Hassan, Abdel Moniem Sadek

    2012-01-01

    Bioautographic assays using TLC play an important role in the search for active compounds from plants. A TLC bioautographic assay has previously been established for the detection of acetylcholinesterase inhibitors but not for lipases. Development of a TLC bioautographic method for detecting lipase inhibitors in plant extracts. After migration of the plant extracts, the TLC plate was sprayed with α-naphtyl acetate and enzyme solutions before incubation at 37°C for 20 min. Finally, the solution of Fast Blue B salt was sprayed onto the TLC plate giving a purple background colouration. Lipase inhibitors were visualised as white spots on the TLC plates. Orlistat (a known lipase inhibitor) inhibited lipase down to 0.01 µg. Methanolic extracts of Camellia sinensis (L.) kuntz and Rosmarinus officinalis L after migration on TLC gave enzymatic inhibition when applied in amounts of 82 and 56 µg, respectively. On the other hand the methanolic extract of Morus alba leaves did not exhibit any lipase inhibitory activity. The screening test was able to detect lipase inhibition by pure reference substances and by compounds present in complex matrices, such as plant extracts. Copyright © 2011 John Wiley & Sons, Ltd.

  9. Methods and Instruments for Fast Neutron Detection

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, David V.; Reeder, Paul L.; Cooper, Matthew W.; McCormick, Kathleen R.; Peurrung, Anthony J.; Warren, Glen A.

    2005-05-01

    Pacific Northwest National Laboratory evaluated the performance of a large-area (~0.7 m2) plastic scintillator time-of-flight (TOF) sensor for direct detection of fast neutrons. This type of sensor is a readily area-scalable technology that provides broad-area geometrical coverage at a reasonably low cost. It can yield intrinsic detection efficiencies that compare favorably with moderator-based detection methods. The timing resolution achievable should permit substantially more precise time windowing of return neutron flux than would otherwise be possible with moderated detectors. The energy-deposition threshold imposed on each scintillator contributing to the event-definition trigger in a TOF system can be set to blind the sensor to direct emission from the neutron generator. The primary technical challenge addressed in the project was to understand the capabilities of a neutron TOF sensor in the limit of large scintillator area and small scintillator separation, a size regime in which the neutral particle’s flight path between the two scintillators is not tightly constrained.

  10. Lagrangian based methods for coherent structure detection

    Energy Technology Data Exchange (ETDEWEB)

    Allshouse, Michael R., E-mail: mallshouse@chaos.utexas.edu [Center for Nonlinear Dynamics and Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States); Peacock, Thomas, E-mail: tomp@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-09-15

    There has been a proliferation in the development of Lagrangian analytical methods for detecting coherent structures in fluid flow transport, yielding a variety of qualitatively different approaches. We present a review of four approaches and demonstrate the utility of these methods via their application to the same sample analytic model, the canonical double-gyre flow, highlighting the pros and cons of each approach. Two of the methods, the geometric and probabilistic approaches, are well established and require velocity field data over the time interval of interest to identify particularly important material lines and surfaces, and influential regions, respectively. The other two approaches, implementing tools from cluster and braid theory, seek coherent structures based on limited trajectory data, attempting to partition the flow transport into distinct regions. All four of these approaches share the common trait that they are objective methods, meaning that their results do not depend on the frame of reference used. For each method, we also present a number of example applications ranging from blood flow and chemical reactions to ocean and atmospheric flows.

  11. Comparison of detection methods for vaginal lactobacilli.

    Science.gov (United States)

    Smidt, I; Kiiker, R; Oopkaup, H; Lapp, E; Rööp, T; Truusalu, K; Štšepetova, J; Truu, J; Mändar, R

    2015-01-01

    Vaginal lactobacilli offer protection against microbiota imbalance and genitourinary tract infections. We compared vaginal lactobacilli in 50 Estonian women of child-bearing age applying culture-based methods, quantitative PCR and next-generation sequencing (NGS). The culture-based methods found three different lactobacilli: Lactobacillus crispatus, Lactobacillus jensenii and Lactobacillus gasseri. Using NGS revealed the presence of L. crispatus in 76%, Lactobacillus iners in 52%, L. jensenii in 47% and L. gasseri in 33% of the samples. According to qPCR, L. iners was present in 67% and L. crispatus in 64% of the samples. The proportions of L. crispatus revealed by qPCR and NGS were in good correlation (R=0.79, P0.05). Good concordance for L. crispatus was also found between the results of the culture-based method and qPCR. Finally, good overlap between the results of the culture-based method and NGS was revealed: in case of a positive NGS result for L. crispatus, the same species was isolated in 95% of samples. The corresponding percentages were 82% for L. jensenii and 86% for L. gasseri. Our data indicate fairly general concordance of the three methods for detecting vaginal lactobacilli, except for L. iners. This points out the importance of standardisation of techniques, and the respective studies should involve cultures applying a medium suitable for the fastidious L. iners.

  12. Method and system for detecting explosives

    Science.gov (United States)

    Reber, Edward L [Idaho Falls, ID; Jewell, James K [Idaho Falls, ID; Rohde, Kenneth W [Idaho Falls, ID; Seabury, Edward H [Idaho Falls, ID; Blackwood, Larry G [Idaho Falls, ID; Edwards, Andrew J [Idaho Falls, ID; Derr, Kurt W [Idaho Falls, ID

    2009-03-10

    A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

  13. A comparative study of two stochastic mode reduction methods

    Energy Technology Data Exchange (ETDEWEB)

    Stinis, Panagiotis

    2005-09-01

    We present a comparative study of two methods for thereduction of the dimensionality of a system of ordinary differentialequations that exhibits time-scale separation. Both methods lead to areduced system of stochastic differential equations. The novel feature ofthese methods is that they allow the use, in the reduced system, ofhigher order terms in the resolved variables. The first method, proposedby Majda, Timofeyev and Vanden-Eijnden, is based on an asymptoticstrategy developed by Kurtz. The second method is a short-memoryapproximation of the Mori-Zwanzig projection formalism of irreversiblestatistical mechanics, as proposed by Chorin, Hald and Kupferman. Wepresent conditions under which the reduced models arising from the twomethods should have similar predictive ability. We apply the two methodsto test cases that satisfy these conditions. The form of the reducedmodels and the numerical simulations show that the two methods havesimilar predictive ability as expected.

  14. Detection of ℓ = 4 and ℓ = 5 modes in 12 years of solar VIRGO-SPM data—tests on Kepler observations of 16 Cyg A and B

    Energy Technology Data Exchange (ETDEWEB)

    Lund, Mikkel Nørup; Kjeldsen, Hans; Christensen-Dalsgaard, Jørgen; Handberg, Rasmus; Aguirre, Victor Silva, E-mail: mikkelnl@phys.au.dk [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2014-02-10

    We present the detection of ℓ = 4 and ℓ = 5 modes in power spectra of the Sun, constructed from 12 yr full-disk VIRGO-SPM data sets. A method for enhancing the detectability of these modes in asteroseismic targets is presented and applied to Kepler data of the two solar analogues 16 Cyg A and B. For these targets, we see indications of a signal from ℓ = 4 modes, while nothing is yet seen for ℓ = 5 modes. We further simulate the power spectra of these stars and from this we estimate that it should indeed be possible to see such indications of ℓ = 4 modes at the present length of the data sets. In the simulation process, we briefly look into the apparent misfit between observed and calculated mode visibilities. We predict that firm detections of at least ℓ = 4 should be possible in any case at the end of the Kepler mission. For ℓ = 5, we do not predict any firm detections from Kepler data.

  15. Detection of l=4 and l=5 modes in 12 years of solar VIRGO-SPM data --- Tests on Kepler observations of 16 Cyg A and B

    CERN Document Server

    Lund, Mikkel Nørup; Christensen-Dalsgaard, Jørgen; Handberg, Rasmus; Aguirre, Victor Silva

    2014-01-01

    We present the detection of l=4 and l=5 modes in power spectra of the Sun, constructed from 12 yr full-disk VIRGO-SPM data sets. A method for enhancing the detectability of these modes in asteroseismic targets is presented and applied to Kepler data of the two solar analogues 16 Cyg A and B. For these targets we see indications of a signal from l=4 modes, while nothing is yet seen for l=5 modes. We further simulate the power spectra of these stars and from this we estimate that it should indeed be possible to see such indications of l=4 modes at the present length of the data sets. In the simulation process we briefly look into the apparent misfit between observed and calculated mode visibilities. We predict that firm detections of at least l=4 should be possible in any case at the end of the Kepler mission. For l=5 we do not predict any firm detections from Kepler data.

  16. Detection of the oscillation mode of measured waveforms in power systems by Prony analysis; Puroni kaisekiho ni yoru denryoku keito ni okeru jissoku hakei no doyo mode kenshutsu ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, K. [Kansai Electaric Power Co. Inc., Osaka (Japan)

    2000-04-01

    This paper describes the detection method of the oscillation modes by Prony analysis from measured data on power systems. A Prony analysis method can obtain the oscillation frequency and logarithmic damping rate corresponding to eigenvalue directly, and is suitable for detecting the oscillation modes. The analysis result showed that longer sampling intervals of 0.2-0.4s allows detection of the long-period oscillation modes from less data, and the index corresponding to waveform areas allows evaluation of the significance of each mode. It was also confirmed that a low-pass filter with a time constant of nearly 0.2s is effective for poor data including various noises, and correction of amplitude and phase shifts is possible by filter. In addition, the study result on application of a Prony analysis method to instantaneous value waveforms showed that analysis of harmonic characteristics is possible by selecting proper analytical parameters, and a Prony analysis method is applicable to analysis of measured data enough. (NEDO)

  17. Nucleic acid detection system and method for detecting influenza

    Science.gov (United States)

    Cai, Hong; Song, Jian

    2015-03-17

    The invention provides a rapid, sensitive and specific nucleic acid detection system which utilizes isothermal nucleic acid amplification in combination with a lateral flow chromatographic device, or DNA dipstick, for DNA-hybridization detection. The system of the invention requires no complex instrumentation or electronic hardware, and provides a low cost nucleic acid detection system suitable for highly sensitive pathogen detection. Hybridization to single-stranded DNA amplification products using the system of the invention provides a sensitive and specific means by which assays can be multiplexed for the detection of multiple target sequences.

  18. Nucleic acid detection system and method for detecting influenza

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Hong; Song, Jian

    2015-03-17

    The invention provides a rapid, sensitive and specific nucleic acid detection system which utilizes isothermal nucleic acid amplification in combination with a lateral flow chromatographic device, or DNA dipstick, for DNA-hybridization detection. The system of the invention requires no complex instrumentation or electronic hardware, and provides a low cost nucleic acid detection system suitable for highly sensitive pathogen detection. Hybridization to single-stranded DNA amplification products using the system of the invention provides a sensitive and specific means by which assays can be multiplexed for the detection of multiple target sequences.

  19. Robust fault tolerant control based on sliding mode method for uncertain linear systems with quantization.

    Science.gov (United States)

    Hao, Li-Ying; Yang, Guang-Hong

    2013-09-01

    This paper is concerned with the problem of robust fault-tolerant compensation control problem for uncertain linear systems subject to both state and input signal quantization. By incorporating novel matrix full-rank factorization technique with sliding surface design successfully, the total failure of certain actuators can be coped with, under a special actuator redundancy assumption. In order to compensate for quantization errors, an adjustment range of quantization sensitivity for a dynamic uniform quantizer is given through the flexible choices of design parameters. Comparing with the existing results, the derived inequality condition leads to the fault tolerance ability stronger and much wider scope of applicability. With a static adjustment policy of quantization sensitivity, an adaptive sliding mode controller is then designed to maintain the sliding mode, where the gain of the nonlinear unit vector term is updated automatically to compensate for the effects of actuator faults, quantization errors, exogenous disturbances and parameter uncertainties without the need for a fault detection and isolation (FDI) mechanism. Finally, the effectiveness of the proposed design method is illustrated via a model of a rocket fairing structural-acoustic.

  20. Accurate calculation methods for natural frequencies of plates with special attention to the higher modes

    NARCIS (Netherlands)

    Oosterhout, G.M.; Hoogt, van der P.J.M.; Spiering, R.M.E.J.

    1995-01-01

    Various computational methods have been studied with respect to their suitability for obtaining very accurate solutions of plate vibration problems, especially for the higher modes. Because of the interest in the higher modes, also higher order effects such as transverse shear deformation and rotati

  1. A multi-parameter decoupling method with a Lamb wave sensor for improving the selectivity of label-free liquid detection.

    Science.gov (United States)

    Zhou, Lianqun; Wu, Yihui; Xuan, Ming; Manceau, Jean-François; Bastien, François

    2012-01-01

    In this paper, a liquid multi-parameter decoupling method with only one Lamb wave sensor is presented. In a Lamb wave sensor, antisymmetric modes (A(01) mode for low frequency, A(03) mode for high frequency) and symmetric modes (S(0) mode) are used to detect multiple parameters of a liquid, such as its density, sound velocity, and viscosity. We found they can play very different roles in the detections. For example, the A(01) mode is very sensitive to the liquid's density but the A(03) mode is sensitive to the sound velocity. Here, the A(0) mode is used to identify the density of the detected liquid and with this density value we obtained the viscosity by the amplitude shifts of the S(0) mode. This could be a way to distinguish an unknown liquid with high sensitivity or to solve the problem of selectivity of label-free detection on biosensors.

  2. Thermoluminescence method for detection of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Pinnioja, S

    1998-12-31

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  3. Active Mode Remote Infrared Spectroscopy Detection of TNT and PETN on Aluminum Substrates

    Directory of Open Access Journals (Sweden)

    John R. Castro-Suarez

    2017-01-01

    Full Text Available Two standoff detection systems were assembled using an infrared telescope coupled to a Fourier transform infrared spectrometer, a cryocooled mercury-cadmium telluride detector, and a telescope-coupled midinfrared excitation source. Samples of the highly energetic materials (HEMs 2,4,6-trinitrotoluene (TNT and pentaerythritol tetranitrate (PETN were deposited on aluminum plates and detected at several source-target distances by carrying out remote infrared spectroscopy (RIRS measurements on the aluminum substrates in active mode. The samples tested were placed at 1–30 m for the RIRS detection experiments. The effect of the angle of incidence/collection of the IR beams on the vibrational band intensities and the signal-to-noise ratios (S/N were investigated. Experiments were performed at ambient temperature. Surface concentrations from 50 to 400 μg/cm2 were studied. Partial least squares regression analysis was applied to the spectra obtained. Overall, RIRS detection in active mode was useful for quantifying the HEMs deposited on the aluminum plates with a high confidence level up to the target-collector distances of 1–25 m.

  4. An Optimal Method For Wake Detection In SAR Images Using Radon Transformation Combined With Wavelet Filters

    CERN Document Server

    Krishnaveni, M; Subashini, P

    2009-01-01

    A new fangled method for ship wake detection in synthetic aperture radar (SAR) images is explored here. Most of the detection procedure applies the Radon transform as its properties outfit more than any other transformation for the detection purpose. But still it holds problems when the transform is applied to an image with a high level of noise. Here this paper articulates the combination between the radon transformation and the shrinkage methods which increase the mode of wake detection process. The latter shrinkage method with RT maximize the signal to noise ratio hence it leads to most optimal detection of lines in the SAR images. The originality mainly works on the denoising segment of the proposed algorithm. Experimental work outs are carried over both in simulated and real SAR images. The detection process is more adequate with the proposed method and improves better than the conventional methods.

  5. Risk assessment of failure modes of gas diffuser liner of V94.2 siemens gas turbine by FMEA method

    Science.gov (United States)

    Mirzaei Rafsanjani, H.; Rezaei Nasab, A.

    2012-05-01

    Failure of welding connection of gas diffuser liner and exhaust casing is one of the failure modes of V94.2 gas turbines which are happened in some power plants. This defect is one of the uncertainties of customers when they want to accept the final commissioning of this product. According to this, the risk priority of this failure evaluated by failure modes and effect analysis (FMEA) method to find out whether this failure is catastrophic for turbine performance and is harmful for humans. By using history of 110 gas turbines of this model which are used in some power plants, the severity number, occurrence number and detection number of failure determined and consequently the Risk Priority Number (RPN) of failure determined. Finally, critically matrix of potential failures is created and illustrated that failure modes are located in safe zone.

  6. Detection of phonon and phason modes in intrinsic colloidal quasicrystals by reconstructing their structure in hyperspace

    Science.gov (United States)

    Hielscher, J.; Martinsons, M.; Schmiedeberg, M.; Kapfer, S. C.

    2017-03-01

    Phasons are additional degrees of freedom which occur in quasicrystals alongside the phonons known from conventional periodic crystals. The rearrangements of particles that are associated with a phason mode are hard to interpret in physical space. We reconstruct the quasicrystal structure by an embedding into extended higher-dimensional space, where phasons correspond to displacements perpendicular to the physical space. In dislocation-free decagonal colloidal quasicrystals annealed with Brownian dynamics simulations, we identify thermal phonon and phason modes. Finite phononic strain is pinned by phasonic excitations even after cooling down to zero temperature. For the phasonic displacements underlying the flip pattern, the reconstruction method gives an approximation within the limits of a multi-mode harmonic ansatz, and points to fundamental limitations of a harmonic picture for phasonic excitations in intrinsic colloidal quasicrystals.

  7. Gluing Lidar Signals Detected in Analog-to-Digital and Photon Counting Modes

    Science.gov (United States)

    Feng, Chang-Zhong; Liu, Bing-Yi; Liu, Jin-Tao; Wu, Song-Hua

    2016-06-01

    Lidar is one of the most effective tools for atmospheric remote sensing. For a ground-based lidar system, the backscattered light usually has large dynamic range. Photon-counting mode has the capability to measure weak signal from high altitude, while Analog-to-Digital mode with better linearity is good at measuring strong signal at low altitude. In some lidar systems, atmospheric return signal is measured in both Analog-to-Digital and Photon Counting modes and combined into an entire profile by using a gluing algorithm. A method for gluing atmospheric return signal is developed and tested. For the Photon Counting signal, the saturation characteristics are analyzed to calculate the coefficients for correction. Then the Analog-to-Digital and Photon Counting signals are glued by a weighted average process. Results show the glued signal is reliable at both low and high altitudes.

  8. Maximum detection range limitation of pulse laser radar with Geiger-mode avalanche photodiode array

    Science.gov (United States)

    Luo, Hanjun; Xu, Benlian; Xu, Huigang; Chen, Jingbo; Fu, Yadan

    2015-05-01

    When designing and evaluating the performance of laser radar system, maximum detection range achievable is an essential parameter. The purpose of this paper is to propose a theoretical model of maximum detection range for simulating the Geiger-mode laser radar's ranging performance. Based on the laser radar equation and the requirement of the minimum acceptable detection probability, and assuming the primary electrons triggered by the echo photons obey Poisson statistics, the maximum range theoretical model is established. By using the system design parameters, the influence of five main factors, namely emitted pulse energy, noise, echo position, atmospheric attenuation coefficient, and target reflectivity on the maximum detection range are investigated. The results show that stronger emitted pulse energy, lower noise level, more front echo position in the range gate, higher atmospheric attenuation coefficient, and higher target reflectivity can result in greater maximum detection range. It is also shown that it's important to select the minimum acceptable detection probability, which is equivalent to the system signal-to-noise ratio for producing greater maximum detection range and lower false-alarm probability.

  9. Gated Geiger mode avalanche photodiode pixels with integrated readout electronics for low noise photon detection

    Science.gov (United States)

    Vilella, E.; Comerma, A.; Alonso, O.; Gascon, D.; Diéguez, A.

    2012-12-01

    Avalanche photodiodes operated in the Geiger mode offer a high intrinsic gain as well as an excellent timing accuracy. These qualities make the sensor specially suitable for those applications where detectors with high sensitivity and low timing uncertainty are required. Moreover, they are compatible with standard CMOS technologies, allowing sensor and front-end electronics integration within the pixel cell. However, the sensor suffers from high levels of intrinsic noise, which may lead to erroneous results and limit the range of detectable signals. They also increase the amount of data that has to be stored. In this work, we present a pixel based on a Geiger-mode avalanche photodiode operated in the gated mode to reduce the probability to detect noise counts interfering with photon arrival events. The readout circuit is based on a two grounds scheme to enable low reverse bias overvoltages and consequently lessen the dark count rate. Experimental characterization of the fabricated pixel with the HV-AMS 0.35 μm standard technology is also presented in this article.

  10. Gated Geiger mode avalanche photodiode pixels with integrated readout electronics for low noise photon detection

    Energy Technology Data Exchange (ETDEWEB)

    Vilella, E., E-mail: evilella@el.ub.es [Department of Electronics, University of Barcelona (UB) Marti i Franques 1, 08028 Barcelona (Spain); Comerma, A. [Department of Structure and Constituents of Matter, University of Barcelona (UB) Marti i Franques 1, 08028 Barcelona (Spain); Alonso, O. [Department of Electronics, University of Barcelona (UB) Marti i Franques 1, 08028 Barcelona (Spain); Gascon, D. [Department of Structure and Constituents of Matter, University of Barcelona (UB) Marti i Franques 1, 08028 Barcelona (Spain); Dieguez, A. [Department of Electronics, University of Barcelona (UB) Marti i Franques 1, 08028 Barcelona (Spain)

    2012-12-11

    Avalanche photodiodes operated in the Geiger mode offer a high intrinsic gain as well as an excellent timing accuracy. These qualities make the sensor specially suitable for those applications where detectors with high sensitivity and low timing uncertainty are required. Moreover, they are compatible with standard CMOS technologies, allowing sensor and front-end electronics integration within the pixel cell. However, the sensor suffers from high levels of intrinsic noise, which may lead to erroneous results and limit the range of detectable signals. They also increase the amount of data that has to be stored. In this work, we present a pixel based on a Geiger-mode avalanche photodiode operated in the gated mode to reduce the probability to detect noise counts interfering with photon arrival events. The readout circuit is based on a two grounds scheme to enable low reverse bias overvoltages and consequently lessen the dark count rate. Experimental characterization of the fabricated pixel with the HV-AMS 0.35 {mu}m standard technology is also presented in this article.

  11. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images.

    Science.gov (United States)

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-08-19

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles' in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians.

  12. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images

    Science.gov (United States)

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-01-01

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles’ in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians. PMID:27548179

  13. Odour Detection Methods: Olfactometry and Chemical Sensors

    Directory of Open Access Journals (Sweden)

    Sara Lovascio

    2011-05-01

    Full Text Available The complexity of the odours issue arises from the sensory nature of smell. From the evolutionary point of view olfaction is one of the oldest senses, allowing for seeking food, recognizing danger or communication: human olfaction is a protective sense as it allows the detection of potential illnesses or infections by taking into account the odour pleasantness/unpleasantness. Odours are mixtures of light and small molecules that, coming in contact with various human sensory systems, also at very low concentrations in the inhaled air, are able to stimulate an anatomical response: the experienced perception is the odour. Odour assessment is a key point in some industrial production processes (i.e., food, beverages, etc. and it is acquiring steady importance in unusual technological fields (i.e., indoor air quality; this issue mainly concerns the environmental impact of various industrial activities (i.e., tanneries, refineries, slaughterhouses, distilleries, civil and industrial wastewater treatment plants, landfills and composting plants as sources of olfactory nuisances, the top air pollution complaint. Although the human olfactory system is still regarded as the most important and effective “analytical instrument” for odour evaluation, the demand for more objective analytical methods, along with the discovery of materials with chemo-electronic properties, has boosted the development of sensor-based machine olfaction potentially imitating the biological system. This review examines the state of the art of both human and instrumental sensing currently used for the detection of odours. The olfactometric techniques employing a panel of trained experts are discussed and the strong and weak points of odour assessment through human detection are highlighted. The main features and the working principles of modern electronic noses (E-Noses are then described, focusing on their better performances for environmental analysis. Odour emission monitoring

  14. Hazard Detection Methods for Lunar Landing

    Science.gov (United States)

    Brady, Tye; Zimpfer, Doug; Robertson, Edward; Epp, Chirold; Paschall, Stephen

    2009-01-01

    The methods and experiences from the Apollo Program are fundamental building blocks for the development of lunar landing strategies for the Constellation Program. Each of the six lunar landing Apollo missions landed under near ideal lighting conditions. The astronauts visually performed terrain relative navigation while looking out of windows, and were greatly aided by external communication and well lit scenes. As the LM approached the landing site, the astronauts performed visual hazard detection and avoidance, also under near-ideal lighting conditions. The astronauts were looking out of the windows trying to the best of their ability to avoid rocks, slopes, and craters and find a safe landing location. NASA has expressed a desire for global lunar access for both crewed and robotic sortie lunar exploration missions (Cook, 2007) (Dale, 2006). Early NASA architecture studies have identified the lunar poles as desirable locations for early lunar missions. These polar missions have less than ideal lighting conditions and will significantly affect the way a crewed vehicle plans to land at such locales. Consequently, a variety of hazard identification methods should be considered for use by the crew to ensure a high degree of safety. This paper discusses such identification methods applicable to the poorly lit polar lunar environment, better ensuring global access for the soon to be designed Lunar Lander Vehicle (LLV).

  15. SCREENING METHODS FOR THE DETECTION OF CARTELS

    Directory of Open Access Journals (Sweden)

    Mihail BUŞU

    2014-06-01

    Full Text Available During their everyday activities, the economic operators conclude a multitude of agreements in tacit or written form, such as: contracts or conventions. Some of these arrangements are absolutely necessary for the development of their current activities. These are agreements which, by respecting the rules of competition, are able to bring benefits to consumers and to the entire economy, as a whole. On the other hand, the economic operators often conclude agreements which are harmful to the economy as well as to the consumers, violating the competition rules. Some examples in this respect are: operators’ agreements on price fixing, on market or customers sharing. Before investigating the violation of competition rules, the relevant authorities should identify the possibility of the existence of such illegalities. The theoretical models for detecting the cartels do represent a proactive tool concerning the antitrust activity of competition authorities. The present paper furnishes a review of the methods for detecting cartels as well as a part of their practical application.

  16. AN IMPROVED CHANNEL DETECTION METHOD FOR IEEE 802.11N MIMO SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Yao Xiaocheng; Jian Haifang; Fang Zhi; Shi Yin

    2011-01-01

    Coexistence and interoperability between 20 MHz and 40 MHz device and modes of operations are stressed in standard IEEE 802.11n system.It is mandate to report the both sub-channels states to Medium Access Control (MAC) at receiver,since for 40 MHz device,it should serve not only 20 MHz but also 40 MHz signals receiving.Both energy detection and carrier sense are employed to detect channel state.In the case of 20/40 M mode,the power difference between the two sub-channels is also detected in order to report the channel state accurately.The simulation results demonstrate that the performance of the proposed methods are much better than the methods which just employ energy detection.Besides,the simulation results show that the proposed methods ensure that the channel sensing is not a roadblock of IEEE 802.11n system design.

  17. Bearing fault detection based on hybrid ensemble detector and empirical mode decomposition

    Science.gov (United States)

    Georgoulas, George; Loutas, Theodore; Stylios, Chrysostomos D.; Kostopoulos, Vassilis

    2013-12-01

    Aiming at more efficient fault diagnosis, this research work presents an integrated anomaly detection approach for seeded bearing faults. Vibration signals from normal bearings and bearings with three different fault locations, as well as different fault sizes and loading conditions are examined. The Empirical Mode Decomposition and the Hilbert Huang transform are employed for the extraction of a compact feature set. Then, a hybrid ensemble detector is trained using data coming only from the normal bearings and it is successfully applied for the detection of any deviation from the normal condition. The results prove the potential use of the proposed scheme as a first stage of an alarm signalling system for the detection of bearing faults irrespective of their loading condition.

  18. Dual-mode bioenabled nano-plasmonic sensors for biological and chemical detection

    Science.gov (United States)

    Kong, Xianming; Squire, Kenny; Xi, Yuting; LeDuff, Paul; Rorrer, Gregory L.; Wang, Alan X.

    2016-03-01

    Plasmonic biosensors have greatly overcome the limitations of conventional optical sensors in terms of sensitivity, tunability, photo-stability, and in vivo applicability. In this paper, we present plasmonic biosensors using bioenabled nanomaterials diatom biosilica, with active surface functionalities as affordable and eco-friendly integration platforms of Ag nanoparticles for label-free detection of biomolecules. Dual-mode plasmon sensing mechanisms, including surface-enhanced Raman scattering (SERS) and refractive-index (RI) sensing will be simultaneously implemented on the plasmonic-biosilica nanostructures to obtain quantitative biosensing with structural resolution of the biomolecules. We have achieved ultra-sensitive detection of Rhodamine 6G (R6G) at concentrations as low as 10-10 M. Furthermore, this substrate was used to detect TNT, illustrating the potential application as viable substrates for monitoring pollutant and toxics in environment.

  19. The simplex method for nonlinear sliding mode control

    Directory of Open Access Journals (Sweden)

    Bartolini G.

    1998-01-01

    Full Text Available General nonlinear control systems described by ordinary differential equations with a prescribed sliding manifold are considered. A method of designing a feedback control law such that the state variable fulfills the sliding condition in finite time is based on the construction of a suitable simplex of vectors in the tangent space of the manifold. The convergence of the method is proved under an obtuse angle condition and a way to build the required simplex is indicated. An example of engineering interest is presented.

  20. Liquid chromatography detection unit, system, and method

    Energy Technology Data Exchange (ETDEWEB)

    Derenzo, Stephen E.; Moses, William W.

    2015-10-27

    An embodiment of a liquid chromatography detection unit includes a fluid channel and a radiation detector. The radiation detector is operable to image a distribution of a radiolabeled compound as the distribution travels along the fluid channel. An embodiment of a liquid chromatography system includes an injector, a separation column, and a radiation detector. The injector is operable to inject a sample that includes a radiolabeled compound into a solvent stream. The position sensitive radiation detector is operable to image a distribution of the radiolabeled compound as the distribution travels along a fluid channel. An embodiment of a method of liquid chromatography includes injecting a sample that comprises radiolabeled compounds into a solvent. The radiolabeled compounds are then separated. A position sensitive radiation detector is employed to image distributions of the radiolabeled compounds as the radiolabeled compounds travel along a fluid channel.

  1. Liquid chromatography detection unit, system, and method

    Science.gov (United States)

    Derenzo, Stephen E.; Moses, William W.

    2015-10-27

    An embodiment of a liquid chromatography detection unit includes a fluid channel and a radiation detector. The radiation detector is operable to image a distribution of a radiolabeled compound as the distribution travels along the fluid channel. An embodiment of a liquid chromatography system includes an injector, a separation column, and a radiation detector. The injector is operable to inject a sample that includes a radiolabeled compound into a solvent stream. The position sensitive radiation detector is operable to image a distribution of the radiolabeled compound as the distribution travels along a fluid channel. An embodiment of a method of liquid chromatography includes injecting a sample that comprises radiolabeled compounds into a solvent. The radiolabeled compounds are then separated. A position sensitive radiation detector is employed to image distributions of the radiolabeled compounds as the radiolabeled compounds travel along a fluid channel.

  2. Majorana Zero Mode Detected with Spin Selective Andreev Reflection in the Vortex of a Topological Superconductor.

    Science.gov (United States)

    Sun, Hao-Hua; Zhang, Kai-Wen; Hu, Lun-Hui; Li, Chuang; Wang, Guan-Yong; Ma, Hai-Yang; Xu, Zhu-An; Gao, Chun-Lei; Guan, Dan-Dan; Li, Yao-Yi; Liu, Canhua; Qian, Dong; Zhou, Yi; Fu, Liang; Li, Shao-Chun; Zhang, Fu-Chun; Jia, Jin-Feng

    2016-06-24

    Recently, theory has predicted a Majorana zero mode (MZM) to induce spin selective Andreev reflection (SSAR), a novel magnetic property which can be used to detect the MZM. Here, spin-polarized scanning tunneling microscopy or spectroscopy has been applied to probe SSAR of MZMs in a topological superconductor of the Bi_{2}Te_{3}/NbSe_{2} heterostructure. The zero-bias peak of the tunneling differential conductance at the vortex center is observed substantially higher when the tip polarization and the external magnetic field are parallel rather than antiparallel to each other. This spin dependent tunneling effect provides direct evidence of MZM and reveals its magnetic property in addition to the zero energy modes. Our work will stimulate MZM research on these novel physical properties and, hence, is a step towards experimental study of their statistics and application in quantum computing.

  3. Majorana Zero Mode Detected with Spin Selective Andreev Reflection in the Vortex of a Topological Superconductor

    Science.gov (United States)

    Sun, Hao-Hua; Zhang, Kai-Wen; Hu, Lun-Hui; Li, Chuang; Wang, Guan-Yong; Ma, Hai-Yang; Xu, Zhu-An; Gao, Chun-Lei; Guan, Dan-Dan; Li, Yao-Yi; Liu, Canhua; Qian, Dong; Zhou, Yi; Fu, Liang; Li, Shao-Chun; Zhang, Fu-Chun; Jia, Jin-Feng

    2016-06-01

    Recently, theory has predicted a Majorana zero mode (MZM) to induce spin selective Andreev reflection (SSAR), a novel magnetic property which can be used to detect the MZM. Here, spin-polarized scanning tunneling microscopy or spectroscopy has been applied to probe SSAR of MZMs in a topological superconductor of the Bi2 Te3 /NbSe2 heterostructure. The zero-bias peak of the tunneling differential conductance at the vortex center is observed substantially higher when the tip polarization and the external magnetic field are parallel rather than antiparallel to each other. This spin dependent tunneling effect provides direct evidence of MZM and reveals its magnetic property in addition to the zero energy modes. Our work will stimulate MZM research on these novel physical properties and, hence, is a step towards experimental study of their statistics and application in quantum computing.

  4. Site-selective detection of vibrational modes of an iron atom in a trinuclear complex

    Energy Technology Data Exchange (ETDEWEB)

    Faus, Isabelle, E-mail: faus@rhrk.uni-kl.de; Rackwitz, Sergej; Wolny, Juliusz A. [University of Kaiserslautern, Department of Physics (Germany); Banerjee, Atanu; Kelm, Harald; Krüger, Hans-Jörg [University of Kaiserslautern, Department of Chemistry (Germany); Schlage, Kai; Wille, Hans-Christian [DESY, PETRA III, P01 (Germany); Schünemann, Volker [University of Kaiserslautern, Department of Physics (Germany)

    2016-12-15

    Nuclear inelastic scattering (NIS) experiments on the trinuclear complex [{sup 57}Fe{L-N_4(CH_2Fc)_2} (CH{sub 3}CN){sub 2}](ClO{sub 4}){sub 2} have been performed. The octahedral iron ion in the complex was labelled with {sup 57}Fe and thereby exclusively the vibrational modes of this iron ion have been detected with NIS. The analysis of nuclear forward scattering (NFS) data yields a ferrous low-spin state for the {sup 57}Fe labelled iron ion. The simulation of the partial density of states (pDOS) for the octahedral low-spin iron(II) ion of the complex by density functional theory (DFT) calculations is in excellent agreement with the experimental pDOS of the complex determined from the NIS data obtained at 80 K. Thereby it was possible to assign almost each of the experimentally observed NIS bands to the corresponding molecular vibrational modes.

  5. System and methods for determining masking signals for applying empirical mode decomposition (EMD) and for demodulating intrinsic mode functions obtained from application of EMD

    Science.gov (United States)

    Senroy, Nilanjan; Suryanarayanan, Siddharth

    2011-03-15

    A computer-implemented method of signal processing is provided. The method includes generating one or more masking signals based upon a computed Fourier transform of a received signal. The method further includes determining one or more intrinsic mode functions (IMFs) of the received signal by performing a masking-signal-based empirical mode decomposition (EMD) using the at least one masking signal.

  6. Two different hematocrit detection methods: Different methods, different results?

    Directory of Open Access Journals (Sweden)

    Schuepbach Reto A

    2010-03-01

    Full Text Available Abstract Background Less is known about the influence of hematocrit detection methodology on transfusion triggers. Therefore, the aim of the present study was to compare two different hematocrit-assessing methods. In a total of 50 critically ill patients hematocrit was analyzed using (1 blood gas analyzer (ABLflex 800 and (2 the central laboratory method (ADVIA® 2120 and compared. Findings Bland-Altman analysis for repeated measurements showed a good correlation with a bias of +1.39% and 2 SD of ± 3.12%. The 24%-hematocrit-group showed a correlation of r2 = 0.87. With a kappa of 0.56, 22.7% of the cases would have been transfused differently. In the-28%-hematocrit group with a similar correlation (r2 = 0.8 and a kappa of 0.58, 21% of the cases would have been transfused differently. Conclusions Despite a good agreement between the two methods used to determine hematocrit in clinical routine, the calculated difference of 1.4% might substantially influence transfusion triggers depending on the employed method.

  7. Integrating a DNA Strand Displacement Reaction with a Whispering Gallery Mode Sensor for Label-Free Mercury (II) Ion Detection.

    Science.gov (United States)

    Wu, Fengchi; Wu, Yuqiang; Niu, Zhongwei; Vollmer, Frank

    2016-07-29

    Mercury is an extremely toxic chemical pollutant of our environment. It has attracted the world's attention due to its high mobility and the ease with which it accumulates in organisms. Sensitive devices and methods specific for detecting mercury ions are, hence, in great need. Here, we have integrated a DNA strand displacement reaction with a whispering gallery mode (WGM) sensor for demonstrating the detection of Hg(2+) ions. Our approach relies on the displacement of a DNA hairpin structure, which forms after the binding of mercury ions to an aptamer DNA sequence. The strand displacement reaction of the DNA aptamer provides highly specific and quantitative means for determining the mercury ion concentration on a label-free WGM sensor platform. Our approach also shows the possibility for manipulating the kinetics of a strand displacement reaction with specific ionic species.

  8. A novel vibration mode testing method for cylindrical resonators based on microphones.

    Science.gov (United States)

    Zhang, Yongmeng; Wu, Yulie; Wu, Xuezhong; Xi, Xiang; Wang, Jianqiu

    2015-01-16

    Non-contact testing is an important method for the study of the vibrating characteristic of cylindrical resonators. For the vibratory cylinder gyroscope excited by piezo-electric electrodes, mode testing of the cylindrical resonator is difficult. In this paper, a novel vibration testing method for cylindrical resonators is proposed. This method uses a MEMS microphone, which has the characteristics of small size and accurate directivity, to measure the vibration of the cylindrical resonator. A testing system was established, then the system was used to measure the vibration mode of the resonator. The experimental results show that the orientation resolution of the node of the vibration mode is better than 0.1°. This method also has the advantages of low cost and easy operation. It can be used in vibration testing and provide accurate results, which is important for the study of the vibration mode and thermal stability of vibratory cylindrical gyroscopes.

  9. A Novel Vibration Mode Testing Method for Cylindrical Resonators Based on Microphones

    Directory of Open Access Journals (Sweden)

    Yongmeng Zhang

    2015-01-01

    Full Text Available Non-contact testing is an important method for the study of the vibrating characteristic of cylindrical resonators. For the vibratory cylinder gyroscope excited by piezo-electric electrodes, mode testing of the cylindrical resonator is difficult. In this paper, a novel vibration testing method for cylindrical resonators is proposed. This method uses a MEMS microphone, which has the characteristics of small size and accurate directivity, to measure the vibration of the cylindrical resonator. A testing system was established, then the system was used to measure the vibration mode of the resonator. The experimental results show that the orientation resolution of the node of the vibration mode is better than 0.1°. This method also has the advantages of low cost and easy operation. It can be used in vibration testing and provide accurate results, which is important for the study of the vibration mode and thermal stability of vibratory cylindrical gyroscopes.

  10. Modeling Shock Train Leading Edge Detection in Dual-Mode Scramjets

    Science.gov (United States)

    Ladeinde, Foluso; Lou, Zhipeng; Li, Wenhai

    2016-11-01

    The objective of this study is to accurately model the detection of shock train leading edge (STLE) in dual-mode scramjet (DMSJ) engines intended for hypersonic flight in air-breathing propulsion systems. The associated vehicles have applications in military warfare and intelligence, and there is commercial interest as well. Shock trains are of interest because they play a significant role in the inability of a DMSJ engine to develop the required propulsive force. The experimental approach to STLE detection has received some attention; as have numerical calculations. However, virtually all of the numerical work focus on mechanically- (i.e., pressure-) generated shock trains, which are much easier to model relative to the phenomenon in the real system where the shock trains are generated by combustion. A focus on combustion, as in the present studies, enables the investigation of the effects of equivalence ratio, which, together with the Mach number, constitutes an important parameter determining mode transition. The various numerical approaches implemented in our work will be reported, with result comparisons to experimental data. The development of an STLE detection procedure in an a priori manner will also be discussed.

  11. Portable organic gas detection sensor based on the effect of guided-mode resonance

    Science.gov (United States)

    Guo, Liang; Wang, Qi; Huang, Yuanshen; Zhang, Dawei

    2017-01-01

    A novel organic gas detection sensor based on the effect of guided-mode resonance is proposed in this paper. The sensor is designed to operate in the visible light band. It contains four main sections: a light source, a miniature gas chamber composed of a guided-mode resonant filter, a diffraction grating, and a CCD image sensor. When bunched visible light is irradiated vertically to the gas chamber, it passes through the gas chamber and diffraction grating, and is then received by the CCD sensor. The optical signal received by the CCD sensor is then reduced to the spectrum using a specific algorithm. When organic gases are injected into the gas chamber, there is a shift in the wavelength of resonant reflection, and the magnitude of this shift is proportional to the refractive index of the gas. The large variation in the refractive indexes of industrially important organic gases means that their characteristic peak wavelengths can be easily identified. As a result, this system can quickly detect organic gases. To verify the feasibility of this technique, we use finite difference time domain solutions to simulate the results. The sensitivity of this type of sensor can reach wavelength differences of 0.001 nm, which means that the sensor has high potential for application in portable, high-precision detection systems.

  12. Single-nanoparticle detection with slot-mode photonic crystal cavities

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Cheng; Kita, Shota; Lončar, Marko, E-mail: loncar@seas.harvard.edu [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States); Quan, Qimin [Rowland Institute at Harvard University, Cambridge, Massachusetts 02142 (United States); Li, Yihang [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States); Department of Electronic Engineering, Tsinghua University, Beijing 100084 (China)

    2015-06-29

    Optical cavities that are capable for detecting single nanoparticles could lead to great progress in early stage disease diagnostics and the study of biological interactions on the single-molecule level. In particular, photonic crystal (PhC) cavities are excellent platforms for label-free single-nanoparticle detection, owing to their high quality (Q) factors and wavelength-scale modal volumes. Here, we demonstrate the design and fabrication of a high-Q (>10{sup 4}) slot-mode PhC nanobeam cavity, which is able to strongly confine light in the slotted regions. The enhanced light-matter interaction results in an order of magnitude improvement in both refractive index sensitivity (439 nm/RIU) and single-nanoparticle sensitivity compared with conventional dielectric-mode PhC cavities. Detection of single polystyrene nanoparticles with radii of 20 nm and 30 nm is demonstrated in aqueous environments (D{sub 2}O), without additional laser and temperature stabilization techniques.

  13. Detecting ATP release by a biosensor method.

    Science.gov (United States)

    Hayashi, Seiji; Hazama, Akihiro; Dutta, Amal K; Sabirov, Ravshan Z; Okada, Yasunobu

    2004-11-09

    Cells release adenosine 5'-triphosphate (ATP) into the extracellular space in response to various stimuli. This released ATP plays an important physiological role in cell-to-cell signal transduction. The bulk ATP concentration can be detected using a conventional luciferin-luciferase assay. However, the ATP concentration in the vicinity of the cell surface is often different from the bulk concentration because of its rapid degradation by ecto-ATPases and because of delayed diffusion due to unstirred layer effects. Here, we describe a simple biosensor method to measure the local ATP concentration on the cell surface in real time. The method is based on the ATP-dependent opening of ligand-gated cation channels of purinergic P2X receptors expressed in undifferentiated pheochromocytoma (PC12) cells or in human embryonic kidney 293 (HEK293) cells stably transfected with recombinant P2X2 purinergic receptors. Under the whole-cell configuration of patch-clamp, a sensor PC12 cell or HEK293 is positioned within the proximity of a target cell, and the P2X-mediated currents induced by ATP released from a given site on the target cell surface is measured. The ATP release is quantified by a calibration procedure utilizing local puff applications of ATP at preset concentrations.

  14. Roundtrip matrix method for calculating the leaky resonant modes of open nanophotonic structures

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

    2014-01-01

    We present a numerical method for calculating quasi-normal modes of open nanophotonic structures. The method is based on scattering matrices and a unity eigenvalue of the roundtrip matrix of an internal cavity, and we develop it in detail with electromagnetic fields expanded on Bloch modes...... cavities are side-coupled and in-line-coupled to an infinite W1 waveguide and show that the scattering spectrum of these types of cavities can be reconstructed from the complex quasi-normal mode frequency....

  15. Extended mode in blocked impurity band detectors for terahertz radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Liao, K. S.; Li, N.; Wang, C.; Li, L.; Jing, Y. L.; Wen, J.; Li, M. Y.; Wang, H.; Zhou, X. H., E-mail: xhzhou@mail.sitp.ac.cn; Li, Z. F.; Lu, W., E-mail: luwei@mail.sitp.ac.cn [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China)

    2014-10-06

    We demonstrate the existence of an interfacial barrier in blocked impurity band (BIB) detectors using temperature-dependent dark current and corresponding theoretical calculations. Considering the effects of the interfacial barrier, the calculated photoresponse is in good agreement with the experimental results. A dual-excitation model, including the direct excitation over the full barrier and excitation to the band minimum with subsequent tunneling into the blocking layer, is proposed to quantitatively explain the observed photoresponse extension. A concept of extended-mode detection is developed to suggest the option for some selective photoresponse in the terahertz region and open the possibility of extending BIB photoresponse to lower frequency.

  16. Sliding mode fault detection and fault-tolerant control of smart dampers in semi-active control of building structures

    Science.gov (United States)

    Yeganeh Fallah, Arash; Taghikhany, Touraj

    2015-12-01

    Recent decades have witnessed much interest in the application of active and semi-active control strategies for seismic protection of civil infrastructures. However, the reliability of these systems is still in doubt as there remains the possibility of malfunctioning of their critical components (i.e. actuators and sensors) during an earthquake. This paper focuses on the application of the sliding mode method due to the inherent robustness of its fault detection observer and fault-tolerant control. The robust sliding mode observer estimates the state of the system and reconstructs the actuators’ faults which are used for calculating a fault distribution matrix. Then the fault-tolerant sliding mode controller reconfigures itself by the fault distribution matrix and accommodates the fault effect on the system. Numerical simulation of a three-story structure with magneto-rheological dampers demonstrates the effectiveness of the proposed fault-tolerant control system. It was shown that the fault-tolerant control system maintains the performance of the structure at an acceptable level in the post-fault case.

  17. Combining BRITE and ground-based photometry for the Beta Cephei star Nu Eridani: impact on photometric pulsation mode identification and detection of several g modes

    CERN Document Server

    Handler, G; Popowicz, A; Pigulski, A; Kuschnig, R; Zoclonska, E; Moffat, A F J; Weiss, W W; Grant, C C; Pablo, H; Whittaker, G N; Rucinski, S M; Ramiaramanantsoa, T; Zwintz, K; Wade, G A

    2016-01-01

    We report a simultaneous ground and space-based photometric study of the Beta Cephei star Nu Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time-series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that the three dominant pulsation modes of Nu Eridani would be incorrec...

  18. Combining BRITE and ground-based photometry for the β Cephei star ν Eridani: impact on photometric pulsation mode identification and detection of several g modes

    Science.gov (United States)

    Handler, G.; Rybicka, M.; Popowicz, A.; Pigulski, A.; Kuschnig, R.; Zocłońska, E.; Moffat, A. F. J.; Weiss, W. W.; Grant, C. C.; Pablo, H.; Whittaker, G. N.; Ruciński, S. M.; Ramiaramanantsoa, T.; Zwintz, K.; Wade, G. A.

    2017-01-01

    We report a simultaneous ground- and space-based photometric study of the β Cephei star ν Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit, we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that three dominant pulsation modes of ν Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy.

  19. Combining BRITE and ground-based photometry for the β Cephei star ν Eridani: impact on photometric pulsation mode identification and detection of several g modes

    Science.gov (United States)

    Handler, G.; Rybicka, M.; Popowicz, A.; Pigulski, A.; Kuschnig, R.; Zocłońska, E.; Moffat, A. F. J.; Weiss, W. W.; Grant, C. C.; Pablo, H.; Whittaker, G. N.; Ruciński, S. M.; Ramiaramanantsoa, T.; Zwintz, K.; Wade, G. A.

    2016-10-01

    We report a simultaneous ground and space-based photometric study of the β Cephei star ν Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time-series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that the three dominant pulsation modes of ν Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy.

  20. A mode matching method for modeling dissipative silencers lined with poroelastic materials and containing mean flow.

    Science.gov (United States)

    Nennig, Benoit; Perrey-Debain, Emmanuel; Ben Tahar, Mabrouk

    2010-12-01

    A mode matching method for predicting the transmission loss of a cylindrical shaped dissipative silencer partially filled with a poroelastic foam is developed. The model takes into account the solid phase elasticity of the sound-absorbing material, the mounting conditions of the foam, and the presence of a uniform mean flow in the central airway. The novelty of the proposed approach lies in the fact that guided modes of the silencer have a composite nature containing both compressional and shear waves as opposed to classical mode matching methods in which only acoustic pressure waves are present. Results presented demonstrate good agreement with finite element calculations provided a sufficient number of modes are retained. In practice, it is found that the time for computing the transmission loss over a large frequency range takes a few minutes on a personal computer. This makes the present method a reliable tool for tackling dissipative silencers lined with poroelastic materials.

  1. Robust fuzzy control for stochastic Markovian jumping systems via sliding mode method

    Science.gov (United States)

    Chen, Bei; Jia, Tinggang; Niu, Yugang

    2016-07-01

    This paper considers the problem of sliding mode control for stochastic Markovian jumping systems by means of fuzzy method. The Takagi-Sugeno (T-S) fuzzy stochastic model subject to state-dependent noise is presented. A key feature in this work is to remove the restricted condition that each local system model had to share the same input channel, which is usually assumed in some existing results. The integral sliding surface is constructed for every mode and the connections among various sliding surfaces are established via a set of coupled matrices. Moreover, the present sliding mode controller including the transition rates of modes can cope with the effect of Markovian switching. It is shown that both the reachability of sliding surfaces and the stability of sliding mode dynamics can be ensured. Finally, numerical simulation results are given.

  2. Nanodiamond-Manganese dual mode MRI contrast agents for enhanced liver tumor detection.

    Science.gov (United States)

    Hou, Weixin; Toh, Tan Boon; Abdullah, Lissa Nurrul; Yvonne, Tay Wei Zheng; Lee, Kuan J; Guenther, Ilonka; Chow, Edward Kai-Hua

    2017-04-01

    Contrast agent-enhanced magnetic resonance (MR) imaging is critical for the diagnosis and monitoring of a number of diseases, including cancer. Certain clinical applications, including the detection of liver tumors, rely on both T1 and T2-weighted images even though contrast agent-enhanced MR imaging is not always reliable. Thus, there is a need for improved dual mode contrast agents with enhanced sensitivity. We report the development of a nanodiamond-manganese dual mode contrast agent that enhanced both T1 and T2-weighted MR imaging. Conjugation of manganese to nanodiamonds resulted in improved longitudinal and transverse relaxivity efficacy over unmodified MnCl2 as well as clinical contrast agents. Following intravenous administration, nanodiamond-manganese complexes outperformed current clinical contrast agents in an orthotopic liver cancer mouse model while also reducing blood serum concentration of toxic free Mn(2+) ions. Thus, nanodiamond-manganese complexes may serve as more effective dual mode MRI contrast agent, particularly in cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Imaging via complete cantilever dynamic detection: general dynamic mode imaging and spectroscopy in scanning probe microscopy

    Science.gov (United States)

    Somnath, Suhas; Collins, Liam; Matheson, Michael A.; Sukumar, Sreenivas R.; Kalinin, Sergei V.; Jesse, Stephen

    2016-10-01

    We develop and implement a multifrequency spectroscopy and spectroscopic imaging mode, referred to as general dynamic mode (GDM), that captures the complete spatially- and stimulus dependent information on nonlinear cantilever dynamics in scanning probe microscopy (SPM). GDM acquires the cantilever response including harmonics and mode mixing products across the entire broadband cantilever spectrum as a function of excitation frequency. GDM spectra substitute the classical measurements in SPM, e.g. amplitude and phase in lock-in detection. Here, GDM is used to investigate the response of a purely capacitively driven cantilever. We use information theory techniques to mine the data and verify the findings with governing equations and classical lock-in based approaches. We explore the dependence of the cantilever dynamics on the tip–sample distance, AC and DC driving bias. This approach can be applied to investigate the dynamic behavior of other systems within and beyond dynamic SPM. GDM is expected to be useful for separating the contribution of different physical phenomena in the cantilever response and understanding the role of cantilever dynamics in dynamic AFM techniques.

  4. Detection of Nanoparticles with a Frequency Locked Whispering Gallery Mode Microresonator

    CERN Document Server

    Swaim, Jon D; Bowen, Warwick P

    2013-01-01

    We detect 39 nm x 10 nm gold nanorods using a microtoroid stabilized via the Pound-Drever-Hall method. Real-time detection is achieved with signal-to-noise ratios up to 12.2. These nanoparticles are a factor of three smaller in volume than any other nanoparticle detected using WGM sensing to date. We show through repeated experiments that the measurements are reliable, and verify the presence of single nanorods on the microtoroid surface using electron microscopy. At our current noise level, the plasmonic enhancement of these nanorods could enable detection of proteins with radii as small as a = 2 nm.

  5. Radio frequency detection assembly and method for detecting radio frequencies

    Science.gov (United States)

    Cown, Steven H.; Derr, Kurt Warren

    2010-03-16

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  6. Look-back-upon tree recurrence method for Geiger-mode avalanche photodiode performance prediction.

    Science.gov (United States)

    Peng, Zhao; Yan, Zhang; Yuming, Hua; Weiping, Qian

    2015-08-15

    This Letter, for the first time, proposes the look-back-upon tree recurrence (LTR) method based on the Poisson statistics for discrete time to predict the performance of Geiger-mode avalanche photodiodes with a short dead time. The results of the proposed method correspond to the results of previous methods for diverse input fluxes. The LTR method possesses very low time and space complexity to allow for the real-time analysis of the Geiger-mode avalanche photodiodes' performance over the entire ranges of dead time and input diversity.

  7. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Nam, Hye Seon; Oh, Kyong Nam; Woo, Si Ho; Kim, Kyeung Eun; Yi, Sang Duk; Park, Jun Young; Kim, Kyong Su; Hwang, Keum Taek

    2000-04-01

    In 1999, we have been studied (1) on the detection of irradiated foods by ESR spectroscopy, by thermoluminescence, and by viscometry for physical measurements, (2) on the detection of hydrocarbons and 2-alkylcyclobutanones derived from fatty foods by GC/MS for chemical measurements, (3) on the screening and detection of irradiated foods by Comet assay and immunochemical (ELISA) technique for biological or biochemical measurements.

  8. Sliding mode based fault detection, reconstruction and fault tolerant control scheme for motor systems.

    Science.gov (United States)

    Mekki, Hemza; Benzineb, Omar; Boukhetala, Djamel; Tadjine, Mohamed; Benbouzid, Mohamed

    2015-07-01

    The fault-tolerant control problem belongs to the domain of complex control systems in which inter-control-disciplinary information and expertise are required. This paper proposes an improved faults detection, reconstruction and fault-tolerant control (FTC) scheme for motor systems (MS) with typical faults. For this purpose, a sliding mode controller (SMC) with an integral sliding surface is adopted. This controller can make the output of system to track the desired position reference signal in finite-time and obtain a better dynamic response and anti-disturbance performance. But this controller cannot deal directly with total system failures. However an appropriate combination of the adopted SMC and sliding mode observer (SMO), later it is designed to on-line detect and reconstruct the faults and also to give a sensorless control strategy which can achieve tolerance to a wide class of total additive failures. The closed-loop stability is proved, using the Lyapunov stability theory. Simulation results in healthy and faulty conditions confirm the reliability of the suggested framework.

  9. Automated mode locking in nonlinear polarization rotation fiber lasers by detection of a discontinuous jump in the polarization state.

    Science.gov (United States)

    Olivier, Michel; Gagnon, Marc-Daniel; Piché, Michel

    2015-03-09

    A strategy to align a mode-locked fiber laser with nonlinear polarization rotation is presented. This strategy is based on measurements of the output polarization state. It is shown that, as the angle of a motorized polarization controller inside the cavity is swept, the laser eventually reaches a mode-locked regime and the values of the Stokes parameters undergo an abrupt change. The sensing of this sudden variation is thus used to detect the mode-locking condition and a feedback mechanism drives the alignment of the polarization controller to force mode locking.

  10. Determination of ethinylestradiol and levonorgestrel in oral contraceptives with HPLC methods with UV detection and UV/fluorescence detection

    Directory of Open Access Journals (Sweden)

    Zorica Arsova-Sarafinovska

    2006-06-01

    Full Text Available Oral contraceptives are pharmaceutical formulations containing an estrogen in a small amount and a synthetic progestin in 5-30 times bigger amount. A sensitive, accurate and rapid method for determination of active compounds is required. We have developed HPLC methods for determination of ethinylestradiol (EED and levonorgestrel (LNG in commercially available tablets. Chromatographic separation was performed on a Purospher® STAR RP-18e reversed-phase column (150 X 4.0 mm I.D.; particle size 5 µm in an isocratic mode with a mobile phase constituted of 47% acetonitrile: 53% water (V/V for both methods. The elution was carried out at a flow rate of 1.50 ml /min. All analyses were performed at room temperature (24 +/- 2°C. In the HPLC method with UV detection (internal standard method both compounds were detected at 215 nm. Drospirenone was used as an internal standard. In HPLC method with UV/fluorescence detection (external standard method LNG was monitored at 242 nm, while EED was detected with fluorescence detector at 310 nm (excitation 285 nm. The methods’ performances were fully validated by a determination of linearity, reproducibility, accuracy and sensitivity. Both methods were applied for determination of Uniformity of Dosage Units. The results obtained with both methods were highly comparable. However, the HPLC method with UV/ fluorescence detection has showed superior sensitivity for EED indicated by 83 times lower detection limit. HPLC method with UV/ fluorescence detection could be recommended as a method of choice for determination of ethinylestradiol, present at a very low dosage level in low-dose oral contraceptives, that also contain bigger amount of synthetic progestin.

  11. A NOVEL INTRUSION DETECTION MODE BASED ON UNDERSTANDABLE NEURAL NETWORK TREES

    Institute of Scientific and Technical Information of China (English)

    Xu Qinzhen; Yang Luxi; Zhao Qiangfu; He Zhenya

    2006-01-01

    Several data mining techniques such as Hidden Markov Model (HMM), artificial neural network,statistical techniques and expert systems are used to model network packets in the field of intrusion detection.In this paper a novel intrusion detection mode based on understandable Neural Network Tree (NNTree) is presented. NNTree is a modular neural network with the overall structure being a Decision Tree (DT), and each non-terminal node being an Expert Neural Network (ENN). One crucial advantage of using NNTrees is that they keep the non-symbolic model ENN's capability of learning in changing environments. Another potential advantage of using NNTrees is that they are actually "gray boxes" as they can be interpreted easily ifthe number of inputs for each ENN is limited. We showed through experiments that the trained NNTree achieved a simple ENN at each non-terminal node as well as a satisfying recognition rate of the network packets dataset.We also compared the performance with that of a three-layer backpropagation neural network. Experimental results indicated that the NNTree based intrusion detection model achieved better performance than the neural network based intrusion detection model.

  12. A rapid ultrasound particle agglutination method for HIV antibody detection: Comparison with conventional rapid HIV tests.

    Science.gov (United States)

    Bystryak, Simon; Ossina, Natalya

    2017-08-24

    We present the results of the feasibility and preliminary studies on analytical performance of a rapid test for detection of human immunodeficiency virus (HIV) antibodies in human serum or plasma that is an important advance in detecting HIV infection. Current methods for rapid testing of antibodies against HIV are qualitative and exhibit poor sensitivity (limit of detection). In this paper, we describe an ultrasound particle agglutination (UPA) method that leads to a significant increase of the sensitivity of conventional latex agglutination tests for HIV antibody detection in human serum or plasma. The UPA method is based on the use of: 1) a dual mode ultrasound, wherein a first single-frequency mode is used to accelerate the latex agglutination process, and then a second swept-frequency mode of sonication is used to disintegrate non-specifically bound aggregates; and 2) a numerical assessment of results of the agglutination process. The numerical assessment is carried out by optical detection and analysis of moving patterns in the resonator cell during the swept-frequency mode. The single-step UPA method is rapid and more sensitive than the three commercial rapid HIV test kits analyzed in the study: analytical sensitivity of the new UPA method was found to be 510-, 115-, and 80-fold higher than that for Capillus™, Multispot™ and Uni-Gold™ Recombigen HIV antibody rapid test kits, respectively. The newly developed UPA method opens up additional possibilities for detection of a number of clinically significant markers in point-of-care settings. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Toward photostable multiplex analyte detection on a single mode planar optical waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Harshini [Los Alamos National Laboratory; Xei, Hongshi [Los Alamos National Laboratory; Anderson, Aaron S [Los Alamos National Laboratory; Grace, Wynne K [Los Alamos National Laboratory; Martinez, Jennifer S [NON LANL; Swanson, Basil [Los Alamos National Laboratory

    2009-01-01

    We have developed a waveguide-based optical biosensor for the sensitive and specific detection of biomarkers associated with disease. Our technology combines the superior optical properties of single-mode planar waveguides, the robust nature of functionalized self-assembled monolayer sensing films and the specificity of fluorescence sandwich immunoassays to detect biomarkers in complex biological samples such as serum, urine and sputum. We have previously reported the adaptation of our technology to the detection of biomarkers associated with breast cancer and anthrax. However, these approaches primarily used phospholipid bilayers as the functional film and organic dyes (ex: AlexaFluors) as the fluorescence reporter. Organic dyes are easily photodegraded and are not amenable to multiplexing because of their narrow Stokes' shift. Here we have developed strategies for conjugation of the detector antibodies with quantum dots for use in a multiplex detection platform. We have previously evaluated dihydroxylipoic acid quantum dots for the detection of a breast cancer biomarker. In this manuscript, we investigate the detection of the Bacillus anthracis protective antigen using antibodies conjugated with polymer-coated quantum dots. Kinetics of binding on the waveguide-based biosensor is reported. We compare the sensitivity of quantum dot labeled antibodies to those labeled with AlexaFluor and demonstrate the photostability of the former in our assay platform. In addition, we compare sulfydryl labeling of the antibody in the hinge region to that of nonspecific amine labeling. This is but the first step in developing a multiplex assay for such biomarkers on our waveguide platform.

  14. Method of stress and measurement modes for research of thin dielectric films of MIS structures

    Science.gov (United States)

    Andreev, Vladimir V.; Maslovsky, Vladimir M.; Andreev, Dmitrii V.; Stolyarov, Alexander A.

    2016-12-01

    The paper proposes a new method of stress and measurement modes for research of thin dielectric films of MIS structures. The method realizes injection of the most part of charge into gate dielectric in one of stress modes: either current owing through dielectric is constant or voltage applied to gate is constant. In order to acquire an additional information about changing of charge state of MIS structure, the stress condition is interrupted in certain time ranges and during these time ranges the mode, in which structure is, is the mode of measurement. In measurement mode, changing of electric fields at interfaces between dielectric and semiconductor is monitored. By using these data, density of charge, which is accumulated in gate dielectric, and its centroid are calculated. Besides, by using these data, one studies processes of generation and relaxation of charge in dielectric. In order to raise precision of the method and reduce an influence of switching effects in measurement mode, density of measurement current should be much lower than density of stress current.

  15. Sliding mode control of photoelectric tracking platform based on the inverse system method

    Directory of Open Access Journals (Sweden)

    Yao Zong Chen

    2016-01-01

    Full Text Available In order to improve the photoelectric tracking platform tracking performance, an integral sliding mode control strategy based on inverse system decoupling method is proposed. The electromechanical dynamic model is established based on multi-body system theory and Newton-Euler method. The coupled multi-input multi-output (MIMO nonlinear system is transformed into two pseudo-linear single-input single-output (SISO subsystems based on the inverse system method. An integral sliding mode control scheme is designed for the decoupled pseudo-linear system. In order to eliminate system chattering phenomenon caused by traditional sign function in sliding-mode controller, the sign function is replaced by the Sigmoid function. Simulation results show that the proposed decoupling method and the control strategy can restrain the influences of internal coupling and disturbance effectively, and has better robustness and higher tracking accuracy.

  16. Co-evolution of strain design methods based on flux balance and elementary mode analysis

    DEFF Research Database (Denmark)

    Machado, Daniel; Herrgard, Markus

    2015-01-01

    optimization to couple cellular growth with the production of a target product. This initiated the development of a family of strain design methods based on the concept of flux balance analysis. Another family of strain design methods, based on the concept of elementary mode analysis, has also been growing......More than a decade ago, the first genome-scale metabolic models for two of the most relevant microbes for biotechnology applications, Escherichia coli and Saccaromyces cerevisiae, were published. Shortly after followed the publication of OptKnock, the first strain design method using bilevel....... Although the computation of elementary modes is hindered by computational complexity, recent breakthroughs have allowed applying elementary mode analysis at the genome scale. Here we review and compare strain design methods and look back at the last 10 years of in silico strain design with constraint...

  17. Mode analysis of structures using the Fourier p-element method

    Institute of Scientific and Technical Information of China (English)

    吴国荣; 钟伟芳

    2003-01-01

    The Fourier p-element method is an improvement to the finite element method, and is particularly suitable for vibration analysis due to the well-behaved Fourier series. In this paper, an iteration procedure is presented for solving the resulting nonlinear eigenvalue problem. Three types of Fourier version shape functions are constructed for analyzing the circular shaft torsional vibration, the plate in-plane vibration and annular plate flexural vibration modes, respectively.The numerical results show that this method can achieve higher accuracy and converge much faster than the FEM based on polynomial interpolation, especially for higher mode analysis.

  18. A matrix method for quasinormal modes: Kerr and Kerr-Sen black holes

    Science.gov (United States)

    Lin, Kai; Qian, Wei-Liang; Pavan, Alan B.; Abdalla, Elcio

    2017-08-01

    In this paper, a matrix method is employed to study the scalar quasinormal modes of Kerr as well as Kerr-Sen black holes. Discretization is applied to transfer the scalar perturbation equation into a matrix form eigenvalue problem, where the resulting radial and angular equations are derived by the method of separation of variables. The eigenvalues, quasinormal frequencies ω and angular quantum numbers λ, are then obtained by numerically solving the resultant homogeneous matrix equation. This work shows that the present approach is an accurate, as well as efficient method for investigating quasinormal modes.

  19. Comparison of Unsupervised Anomaly Detection Methods

    Data.gov (United States)

    National Aeronautics and Space Administration — Several different unsupervised anomaly detection algorithms have been applied to Space Shuttle Main Engine (SSME) data to serve the purpose of developing a...

  20. Geiger-mode avalanche photodiode ladar receiver performance characteristics and detection statistics.

    Science.gov (United States)

    Gatt, Philip; Johnson, Steven; Nichols, Terry

    2009-06-10

    The performance of single and multielement Geiger-mode avalanche photodiode (GM-APD) devices are investigated as a function of the detector's reset or dead time. The theoretical results, developed herein, capture the effects of both quantum fluctuations and speckle noise and are shown to agree with Monte Carlo simulation measurements. First, a theory for the mean response or count rate to an arbitrary input flux is developed. The probability that the GM-APD is armed is shown to be the ratio of this mean response to the input flux. This arm probability, P(A), is then utilized to derive the signal photon detection efficiency (SPDE), which is the fraction of signal photons that are detected. The SPDE is a function of the input flux, the arm probability, and the dead time. When the dead time is zero, GM-APDs behave linearly, P(A) is unity, and the SPDE theory is simplified to the detector's effective quantum efficiency. When the dead time is long compared to the acquisition gate time, the theory converges to previously published "infinite" dead-time theories. The SPDE theory is then applied to develop other key ladar performance metrics, e.g., signal-to-noise ratio and detection statistics. The GM-APD detection statistics are shown to converge to that of a linear photon counting device when the combined signal and noise flux is much less than the reset rate. For higher flux levels, the SPDE degrades, due to a decreased arm probability, and the detection probability degrades relative to that of a linear device.

  1. System and method for detecting cells or components thereof

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Marc D. (Ames, IA); Lipert, Robert J. (Ames, IA); Doyle, Robert T. (Ames, IA); Grubisha, Desiree S. (Corona, CA); Rahman, Salma (Ames, IA)

    2009-01-06

    A system and method for detecting a detectably labeled cell or component thereof in a sample comprising one or more cells or components thereof, at least one cell or component thereof of which is detectably labeled with at least two detectable labels. In one embodiment, the method comprises: (i) introducing the sample into one or more flow cells of a flow cytometer, (ii) irradiating the sample with one or more light sources that are absorbed by the at least two detectable labels, the absorption of which is to be detected, and (iii) detecting simultaneously the absorption of light by the at least two detectable labels on the detectably labeled cell or component thereof with an array of photomultiplier tubes, which are operably linked to two or more filters that selectively transmit detectable emissions from the at least two detectable labels.

  2. Whistler mode waves and Hall fields detected by MMS during a dayside magnetopause crossing

    Science.gov (United States)

    Contel, O. Le; Retinò, A.; Breuillard, H.; Mirioni, L.; Robert, P.; Chasapis, A.; Lavraud, B.; Chust, T.; Rezeau, L.; Wilder, F. D.; Graham, D. B.; Argall, M. R.; Gershman, D. J.; Lindqvist, P.-A.; Khotyaintsev, Y. V.; Marklund, G.; Ergun, R. E.; Goodrich, K. A.; Burch, J. L.; Torbert, R. B.; Needell, J.; Chutter, M.; Rau, D.; Dors, I.; Russell, C. T.; Magnes, W.; Strangeway, R. J.; Bromund, K. R.; Leinweber, H. K.; Plaschke, F.; Fischer, D.; Anderson, B. J.; Le, G.; Moore, T. E.; Pollock, C. J.; Giles, B. L.; Dorelli, J. C.; Avanov, L.; Saito, Y.

    2016-06-01

    We present Magnetospheric Multiscale (MMS) mission measurements during a full magnetopause crossing associated with an enhanced southward ion flow. A quasi-steady magnetospheric whistler mode wave emission propagating toward the reconnection region with quasi-parallel and oblique wave angles is detected just before the opening of the magnetic field lines and the detection of escaping energetic electrons. Its source is likely the perpendicular temperature anisotropy of magnetospheric energetic electrons. In this region, perpendicular and parallel currents as well as the Hall electric field are calculated and found to be consistent with the decoupling of ions from the magnetic field and the crossing of a magnetospheric separatrix region. On the magnetosheath side, Hall electric fields are found smaller as the density is larger but still consistent with the decoupling of ions. Intense quasi-parallel whistler wave emissions are detected propagating both toward and away from the reconnection region in association with a perpendicular anisotropy of the high-energy part of the magnetosheath electron population and a strong perpendicular current, which suggests that in addition to the electron diffusion region, magnetosheath separatrices could be a source region for whistler waves.

  3. Superparamagnetic nanoparticle detection system by using a fundamental mode orthogonal fluxgate (FM-OFG gradiometer

    Directory of Open Access Journals (Sweden)

    Hikaru Karo

    2017-05-01

    Full Text Available A new magnetic nanoparticle detection system by using a fundamental mode orthogonal fluxgate (FM-OFG gradiometer and ac magnetizing coil has been developed. The FM-OFG gradiometer has an active canceling coil on each of its sensor heads against the common magnetic field input to avoid the saturation of the amorphous wire core by a strong ac magnetic field. In addition, the ac magnetizing coil has an adjusting capability to make ac magnetic field strength affecting each of the gradiometer heads equal, which allows us to use a high gain amplifier at the latter stage. Two types of the gradiometer are tested: one is parallel configuration in which two sensor heads are placed in parallel side by side, the other is axial configuration in which two sensor heads are placed axially. Detectable distance was investigated using a 5μL (≈100μg in Fe atomic amount magnetic nanoparticle sample. The maximum detectable distance for the parallel gradiometer is 17 mm, and that for the axial one is 18 mm.

  4. Real-Time Detection of Staphylococcus Aureus Using Whispering Gallery Mode Optical Microdisks

    Directory of Open Access Journals (Sweden)

    Hala Ghali

    2016-05-01

    Full Text Available Whispering Gallery Mode (WGM microresonators have recently been studied as a means to achieve real-time label-free detection of biological targets such as virus particles, specific DNA sequences, or proteins. Due to their high quality (Q factors, WGM resonators can be highly sensitive. A biosensor also needs to be selective, requiring proper functionalization of its surface with the appropriate ligand that will attach the biomolecule of interest. In this paper, WGM microdisks are used as biosensors for detection of Staphylococcus aureus. The microdisks are functionalized with LysK, a phage protein specific for staphylococci at the genus level. A binding event on the surface shifts the resonance peak of the microdisk resonator towards longer wavelengths. This reactive shift can be used to estimate the surface density of bacteria that bind to the surface of the resonator. The limit of detection of a microdisk with a Q-factor around 104 is on the order of 5 pg/mL, corresponding to 20 cells. No binding of Escherichia coli to the resonators is seen, supporting the specificity of the functionalization scheme.

  5. Asymptotic ideal observers and surrogate figures of merit for signal detection with list-mode data.

    Science.gov (United States)

    Clarkson, Eric

    2012-10-01

    The asymptotic form for the likelihood ratio is derived for list-mode data generated by an imaging system viewing a possible signal in a randomly generated background. This calculation provides an approximation to the likelihood ratio that is valid in the limit of large number of list entries, i.e., a large number of photons. These results are then used to derive surrogate figures of merit, quantities that are correlated with ideal-observer performance on detection tasks, as measured by the area under the receiver operating characteristic curve, but are easier to compute. A key component of these derivations is the determination of asymptotic forms for the Fisher information for the signal amplitude in the limit of a large number of counts or a long exposure time. This quantity is useful in its own right as a figure of merit (FOM) for the task of estimating the signal amplitude. The use of the Fisher information in detection tasks is based on the fact that it provides an approximation for ideal-observer detectability when the signal is weak. For both the fixed-count and fixed-time cases, four surrogate figures of merit are derived. Two are based on maximum likelihood reconstructions; one uses the characteristic functional of the random backgrounds. The fourth surrogate FOM is identical in the two cases and involves an integral over attribute space for each of a randomly generated sequence of backgrounds.

  6. Detection of coatings within liquid-filled tubes and containers by mode conversion of leaky Lamb waves

    Directory of Open Access Journals (Sweden)

    M. Schmitt

    2013-05-01

    Full Text Available In this paper, a new acoustic sensor principle for coating detection within liquid-filled tubes and containers based on mode conversion of leaky Lamb waves is introduced. Leaky Lamb waves are excited and detected by single-phase transducers, which are attached on the outer side of a tube or container. By transmission time and amplitude measurements, coating formation within the liquid-filled tube and container is detected non-invasively. This new sensor principle is subdivided into the separate considerations of Lamb wave excitation, mode conversion and inverse mode conversion. The Lamb wave excitation by a single-phase transducer is visualized by scanning laser Doppler vibrometer imaging. The mode conversion process of leaky Lamb waves is measured by membrane hydrophone measurements and Schlieren visualization; afterwards, the measured emission angles are compared with the theoretical one. The inverse mode conversion process of pressure waves back to leaky Lamb waves is visualized by Schlieren images. By merging the results of Lamb wave excitation, mode conversion and inverse mode conversion, the new sensor concept is explained. Theoretical considerations and measurement results of adhesive tape coating inside a liquid-filled plastic tube and a liquid-filled stainless steel container verify the new acoustic sensor principle. Finally the measuring sensitivity and the technical realization are discussed.

  7. A Discrete-Time Chattering Free Sliding Mode Control with Multirate Sampling Method for Flight Simulator

    Directory of Open Access Journals (Sweden)

    Yunjie Wu

    2013-01-01

    Full Text Available In order to improve the tracking accuracy of flight simulator and expend its frequency response, a multirate-sampling-method-based discrete-time chattering free sliding mode control is developed and imported into the systems. By constructing the multirate sampling sliding mode controller, the flight simulator can perfectly track a given reference signal with an arbitrarily small dynamic tracking error, and the problems caused by a contradiction of reference signal period and control period in traditional design method can be eliminated. It is proved by theoretical analysis that the extremely high dynamic tracking precision can be obtained. Meanwhile, the robustness is guaranteed by sliding mode control even though there are modeling mismatch, external disturbances and measure noise. The validity of the proposed method is confirmed by experiments on flight simulator.

  8. Low-limit detection of NO2 by longitudinal mode selection in a photoacoustic resonant system

    Indian Academy of Sciences (India)

    F Yehya; A K Chaudhary

    2013-09-01

    The paper reports the pulsed laser-based photoacoustic (PA) spectroscopy of NO2 in a resonant PA cavity with special filters made of stainless steel. The PA cell along with special types of sound filters are designed and fabricated to excite only the second-order longitudinal mode inside the cavity. The second harmonic, i.e. = 532 nm pulse width, of 7 ns obtained from -switched Nd:YAG laser at 10 Hz repetition rate has been used to study the saturation behaviour of the PA signal and absorption coefficient with respect to the input laser energy. Generally, the -factor of longitudinal modes in the acoustic cavities is quite low. However, by modifying the design of the cell and the filter, we can achieve high value of = 30. The combination of special filter along with the experimental data acquisition technique helped us to achieve the minimum detection concentration of NO2 of the order of 9 ppbV which is much better than the previous value of the same PA cell without filter [Yehya and Chaudhary, Appl. Phys. B 106, 953 (2012)].

  9. Community Detection Based on Link Prediction Methods

    CERN Document Server

    Cheng, Hui-Min

    2016-01-01

    Community detection and link prediction are both of great significance in network analysis, which provide very valuable insights into topological structures of the network from diffrent perspectives. In this paper, we propose a novel community detection algorithm with inclusion of link prediction, motivated by the question whether link prediction can be devoted to improve the accuracy of community partition. For link prediction, we propose two novel indices to compute the similarity between each pair of nodes, one of which aims to add missing links, and the other tries to remove spurious edges. Extensive experiments are conducted on benchmark data sets, and the results of our proposed algorithm are compared with two classes of baselines. In conclusion, our proposed algorithm is competitive, revealing that link prediction does improve the precision of community detection.

  10. Online Fault Detection of Permanent Magnet Demagnetization for IPMSMs by Nonsingular Fast Terminal-Sliding-Mode Observer

    Directory of Open Access Journals (Sweden)

    Kai-Hui Zhao

    2014-12-01

    Full Text Available To prevent irreversible demagnetization of a permanent magnet (PM for interior permanent magnet synchronous motors (IPMSMs by flux-weakening control, a robust PM flux-linkage nonsingular fast terminal-sliding-mode observer (NFTSMO is proposed to detect demagnetization faults. First, the IPMSM mathematical model of demagnetization is presented. Second, the construction of the NFTSMO to estimate PM demagnetization faults in IPMSM is described, and a proof of observer stability is given. The fault decision criteria and fault-processing method are also presented. Finally, the proposed scheme was simulated using MATLAB/Simulink and implemented on the RT-LABplatform. A number of robustness tests have been carried out. The scheme shows good performance in spite of speed fluctuations, torque ripples and the uncertainties of stator resistance.

  11. DIAGNOdent: an optical method for caries detection.

    Science.gov (United States)

    Lussi, A; Hibst, R; Paulus, R

    2004-01-01

    The onset of caries is characterized by demineralization of dental hard tissues. Optimal fluoridation with respective oral hygiene habits and diet may stop the progression of a lesion and even allow for its remineralization. The aim of modern dentistry must be a preventive approach rather than invasive repair of the disease. This is possible only with early detection and respective preventive measures. Some of today's diagnostic tools are not sensitive enough to detect this early onset of destruction. Tools based on fluorescence could have the possibility to overcome this problem. This overview will focus on today's knowledge of one possible tool, the DIAGNOdent.

  12. Automated detection of circinate exudates in retina digital images using empirical mode decomposition and the entropy and uniformity of the intrinsic mode functions.

    Science.gov (United States)

    Lahmiri, Salim; Boukadoum, Mounir

    2014-08-01

    This work presents a new automated system to detect circinate exudates in retina digital images. It operates as follows: the true color image is converted to gray levels, and contrast-limited adaptive histogram equalization (CLAHE) is applied to it before undergoing empirical mode decomposition (EMD) as intrinsic mode functions (IMFs). The entropies and uniformities of the first two IMFs are then computed to form a feature vector that is fed to a support vector machine (SVM) for classification. The experimental results using a set of 45 images (23 normal images and 22 images with circinate exudates taken from the STARE database) and tenfold cross-validation indicate that the proposed approach outperforms previous works found in the literature, with perfect classification. In addition, the image processing time was exudate detection system fit for use in a clinical environment.

  13. EMUstack: An open source route to insightful electromagnetic computation via the Bloch mode scattering matrix method

    Science.gov (United States)

    Sturmberg, Björn C. P.; Dossou, Kokou B.; Lawrence, Felix J.; Poulton, Christopher G.; McPhedran, Ross C.; Martijn de Sterke, C.; Botten, Lindsay C.

    2016-05-01

    We describe EMUstack, an open-source implementation of the Scattering Matrix Method (SMM) for solving field problems in layered media. The fields inside nanostructured layers are described in terms of Bloch modes that are found using the Finite Element Method (FEM). Direct access to these modes allows the physical intuition of thin film optics to be extended to complex structures. The combination of the SMM and the FEM makes EMUstack ideally suited for studying lossy, high-index contrast structures, which challenge conventional SMMs.

  14. Enhanced method to reconstruct mode shapes of continuous scanning measurements using the Hilbert Huang transform and the modal analysis method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jongsuh; Hussain, Syed Hassaan; Wang, Semyung, E-mail: smwang@gist.ac.kr; Park, Kyihwan [School of Mechatronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

    2014-09-15

    Generally, it is time consuming to experimentally identify the operating deflection shape or mode shape of a structure. To overcome this problem, the Hilbert Huang transform (HHT) technique has been recently proposed. This technique is used to extract the mode shape from measurements that continuously measure the vibration of a region of interest within a structure using a non-contact laser sensor. In previous research regarding the HHT, two technical processes were needed to obtain the mode shape for each mode. The purpose of this study is to improve and complement our previous research, and for this purpose, a modal analysis approach is adapted without using the two technical processes to obtain an accurate un-damped impulse response of each mode for continuous scanning measurements. In addition, frequency response functions for each type of beam are derived, making it possible to make continuously scanned measurements along a straight profile. In this paper, the technical limitations and drawbacks of the damping compensation technique used in previous research are identified. In addition, the separation of resonant frequency (the Doppler effect) that occurs in continuous scanning measurements and the separation of damping phenomenon are also observed. The proposed method is quantitatively verified by comparing it with the results obtained from a conventional approach to estimate the mode shape with an impulse response.

  15. Enhanced method to reconstruct mode shapes of continuous scanning measurements using the Hilbert Huang transform and the modal analysis method

    Science.gov (United States)

    Lee, Jongsuh; Hussain, Syed Hassaan; Wang, Semyung; Park, Kyihwan

    2014-09-01

    Generally, it is time consuming to experimentally identify the operating deflection shape or mode shape of a structure. To overcome this problem, the Hilbert Huang transform (HHT) technique has been recently proposed. This technique is used to extract the mode shape from measurements that continuously measure the vibration of a region of interest within a structure using a non-contact laser sensor. In previous research regarding the HHT, two technical processes were needed to obtain the mode shape for each mode. The purpose of this study is to improve and complement our previous research, and for this purpose, a modal analysis approach is adapted without using the two technical processes to obtain an accurate un-damped impulse response of each mode for continuous scanning measurements. In addition, frequency response functions for each type of beam are derived, making it possible to make continuously scanned measurements along a straight profile. In this paper, the technical limitations and drawbacks of the damping compensation technique used in previous research are identified. In addition, the separation of resonant frequency (the Doppler effect) that occurs in continuous scanning measurements and the separation of damping phenomenon are also observed. The proposed method is quantitatively verified by comparing it with the results obtained from a conventional approach to estimate the mode shape with an impulse response.

  16. Ultrasound Imaging Methods for Breast Cancer Detection

    NARCIS (Netherlands)

    Ozmen, N.

    2014-01-01

    The main focus of this thesis is on modeling acoustic wavefield propagation and implementing imaging algorithms for breast cancer detection using ultrasound. As a starting point, we use an integral equation formulation, which can be used to solve both the forward and inverse problems. This thesis c

  17. New transfer matrix method for long-period fiber gratings with coupled multiple cladding modes

    Institute of Scientific and Technical Information of China (English)

    Guodong Wang; Yunjian Wang

    2011-01-01

    A new transfer matrix method for long-period fiber gratings with coupled multiple cladding modes is proposed and numerically characterized. The transmission spectra of uniform and non-uniform long-period fiber gratings are numerically characterized. The theoretical results excellently agree with the experimental measurements. Compared with commonly used methods, such as using the fourth-order adaptive step size control of the Runge-Kutta algorithm in solving the coupled mode equation, the new transfer matrix method exhibits a faster calculation speed.%@@ A new transfer matrix method for long-period fiber gratings with coupled multiple cladding modes is proposed and numerically characterized.The transmission spectra of uniform and non-uniform longperiod fiber gratings are numerically characterized.The theoretical results excellently agree with the experimental measurements.Compared with commonly used methods,such as using the fourth-order adaptive step size control of the Runge-Kutta algorithm in solving the coupled mode equation,the new transfer matrix method exhibits a faster calculation speed.

  18. Statistical Methods for Detecting Stellar Occultations by Kuiper Belt Objects the Taiwanese-American Occultation Survey

    CERN Document Server

    Liang, C L; De Pater, I; Alcock, C B; Axelrod, T; Wang, A; Liang, Chyng-Lan; Rice, John A.; Pater, Imke de; Alcock, Charles; Axelrod, Tim; Wang, Andrew

    2002-01-01

    The Taiwanese-American Occultation Survey (TAOS) will detect objects in the Kuiper Belt, by measuring the rate of occultations of stars by these objects, using an array of three to four 50cm wide-field robotic telescopes. Thousands of stars will be monitored, resulting in hundreds of millions of photometric measurements per night. To optimize the success of TAOS, we have investigated various methods of gathering and processing the data and developed statistical methods for detecting occultations. In this paper we discuss these methods. The resulting estimated detection efficiencies will be used to guide the choice of various operational parameters determining the mode of actual observation when the telescopes come on line and begin routine observations. In particular we show how real-time detection algorithms may be constructed, taking advantage of having multiple telescopes. We also discuss a retrospective method for estimating the rate at which occultations occur.

  19. First screening method for the simultaneous detection of seven allergens by liquid chromatography mass spectrometry.

    Science.gov (United States)

    Heick, J; Fischer, M; Pöpping, B

    2011-02-18

    The development of a multi-method for the detection of seven allergens based on liquid chromatography and triple-quadrupole tandem mass spectrometry in multiple reaction mode is described. It is based on extraction of the allergenic proteins from a food matrix, followed by enzymatic digestion with trypsin. The chosen marker peptides were implemented into one method that is capable of the simultaneous detection of milk, egg, soy, hazelnut, peanut, walnut and almond. This method has been used to detect all seven allergenic commodities from incurred reference bread material, which was baked according to a standard recipe from the baking industry. Detected concentrations ranged from 10 to 1000 μg/g, demonstrating that the mass spectrometric based method is a useful tool for allergen screening.

  20. Detection of coatings within liquid-filled tubes and containers by mode conversion of leaky Lamb waves

    OpenAIRE

    SCHMITT, M; Schmidt, K.; Olfert, S.; Rautenberg, J.; Lindner, G; B. Henning; L. M. Reindl

    2013-01-01

    In this paper, a new acoustic sensor principle for coating detection within liquid-filled tubes and containers based on mode conversion of leaky Lamb waves is introduced. Leaky Lamb waves are excited and detected by single-phase transducers, which are attached on the outer side of a tube or container. By transmission time and amplitude measurements, coating formation within the liquid-filled tube and container is detected non-invasively. This new sensor principle is subdivid...

  1. Rapid method for detection of salmonella in meat

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a rapid method for the detection of Salmonella in meat as well as to a kit for performing said method. The method provides a time-to-result of less than 8 hours.......The present invention relates to a rapid method for the detection of Salmonella in meat as well as to a kit for performing said method. The method provides a time-to-result of less than 8 hours....

  2. Validation of the chlorophyll fluorescence imaging method (CFI for early detection of herbicide resistance in weeds

    Directory of Open Access Journals (Sweden)

    Menegat, Alexander

    2014-02-01

    Full Text Available The increasing number of herbicide tolerant weed populations is illustrating the increasing demand for reliable methods for an accelerated detection of herbicide tolerance compared to greenhouse studies. Several methods for resistance quick detection have been published in previous years. One of the recent methods is the Chlorophyll Fluorescence Imaging Method (CFI. For this method changes in photosynthetic activity of the target organisms, caused by herbicides, are determined. General assumption of this method in terms of herbicide resistance detection is that each herbicidal compound, independent of the mode of action, will cause changes within the photosynthetic apparatus of the target organisms. This effect already could be confirmed for several modes of action (PSII, ALS, ACCase, EPSPS, synth. Auxins. Aim of this study is to validate this novel method on the basis of greenhouse experiments and single nucleotide polymorphisms (SNP analysis. The resistance profiles of 10 black-grass populations (Alopecurus myosuroides Huds. have been determined in greenhouse herbicide efficacy trials and constitutive SNP analyses of the survivors. With the CFI-method it was possible to detect the resistance profile as well as the resistance frequency within the populations. The results from the greenhouse experiments could be reproduced with conformity of 94%. This result is valid for the tested herbicides mesosulfuron, pyroxsulam as well as clodinafop and pinoxaden.

  3. Two-Dimensional Change Detection Methods Remote Sensing Applications

    CERN Document Server

    Ilsever, Murat

    2012-01-01

    Change detection using remotely sensed images has many applications, such as urban monitoring, land-cover change analysis, and disaster management. This work investigates two-dimensional change detection methods. The existing methods in the literature are grouped into four categories: pixel-based, transformation-based, texture analysis-based, and structure-based. In addition to testing existing methods, four new change detection methods are introduced: fuzzy logic-based, shadow detection-based, local feature-based, and bipartite graph matching-based. The latter two methods form the basis for a

  4. A transversal substructuring mode matching method applied to the acoustic analysis of dissipative mufflers

    Science.gov (United States)

    Albelda, J.; Denia, F. D.; Torres, M. I.; Fuenmayor, F. J.

    2007-06-01

    To carry out the acoustic analysis of dissipative silencers with uniform cross-section, the application of the mode matching method at the geometrical discontinuities is an attractive option from a computational point of view. The consideration of this methodology assumes, in general, that the modes associated with the transversal geometry of each element with uniform cross-section are known for the excitation frequencies considered in the analysis. The calculation of the transversal modes is not, however, a simple task when the acoustic system involves perforated elements and absorbent materials. The current work presents a modal approach to calculate the transversal modes and the corresponding axial wavenumbers for dissipative mufflers of uniform (but arbitrary) cross-section. The proposed technique is based on the division of the transversal section into subdomains and the subsequent use of a substructuring procedure with two sets of modes to improve the convergence. The former set of modes fulfils the condition of zero pressure at the common boundary between transversal subdomains while the latter satisfies the condition of zero derivative in the direction normal to the boundary. The approach leads to a versatile methodology with a moderate computational effort that can be applied to mufflers commonly found in real applications. To validate the procedure presented in this work, comparisons are provided with finite element predictions and results available in the literature, showing a good agreement. In addition, the procedure is applied to an example of practical interest.

  5. Anomaly-based Network Intrusion Detection Methods

    Directory of Open Access Journals (Sweden)

    Pavel Nevlud

    2013-01-01

    Full Text Available The article deals with detection of network anomalies. Network anomalies include everything that is quite different from the normal operation. For detection of anomalies were used machine learning systems. Machine learning can be considered as a support or a limited type of artificial intelligence. A machine learning system usually starts with some knowledge and a corresponding knowledge organization so that it can interpret, analyse, and test the knowledge acquired. There are several machine learning techniques available. We tested Decision tree learning and Bayesian networks. The open source data-mining framework WEKA was the tool we used for testing the classify, cluster, association algorithms and for visualization of our results. The WEKA is a collection of machine learning algorithms for data mining tasks.

  6. Standardized Methods for Detection of Poliovirus Antibodies.

    Science.gov (United States)

    Weldon, William C; Oberste, M Steven; Pallansch, Mark A

    2016-01-01

    Testing for neutralizing antibodies against polioviruses has been an established gold standard for assessing individual protection from disease, population immunity, vaccine efficacy studies, and other vaccine clinical trials. Detecting poliovirus specific IgM and IgA in sera and mucosal specimens has been proposed for evaluating the status of population mucosal immunity. More recently, there has been a renewed interest in using dried blood spot cards as a medium for sample collection to enhance surveillance of poliovirus immunity. Here, we describe the modified poliovirus microneutralization assay, poliovirus capture IgM and IgA ELISA assays, and dried blood spot polio serology procedures for the detection of antibodies against poliovirus serotypes 1, 2, and 3.

  7. Orthogonality of Modes of Structures When Using the Exact Transcendental Stiffness Matrix Method

    Directory of Open Access Journals (Sweden)

    K.L. Chan

    2000-01-01

    Full Text Available This paper presents theory, physical insight and results for mode orthogonality of piecewise continuous structures, including both coincident and non-coincident natural frequencies. The structures are ones for which exact member equations have been obtained by solving the governing differential equations, e.g. as can be done for members of plane frames or prismatic plate assemblies. Such member equations are transcendental functions of the distributed member mass and the frequency. They are used to obtain a transcendental overall stiffness matrix for the structure, from which the natural frequencies are extracted by using the Wittrick-Williams algorithm, prior to using any existing method to find the modes which are examined from the orthogonality viewpoint in this paper. The natural frequencies and modes found are the exact values for the structure in the sense that the usual finite element method approximations are avoided.

  8. Investigations on Shaped Mirror Systems in Quasi-Optical Mode Converters Based on Irradiance Moments Method

    Directory of Open Access Journals (Sweden)

    Hai Wang

    2016-01-01

    Full Text Available A method of transforming high-order Gaussian beams (GBs mode into circular symmetry fundamental Gaussian beam (FGB mode with arbitrary waist size is presented using irradiance moments method in quasi-optical (QO mode converters. The double shaped mirrors correcting amplitude and phase simultaneously are generated by a single incidence irradiance sampling data and known ideal output FGB taking advantage of linear moment matching technique and Fresnel diffraction theory, which can be applied to a wide frequency range especially significant for terahertz band. The numerical coding procedure of creating double correcting mirrors and its fast convergence speed are discussed at 325 GHz. Numerical and experimental comparisons reveal the conclusion that enhancing surface precision and increasing moments order can improve main lobe levels.

  9. Novel Methods for Detecting Buried Explosive Devices

    Science.gov (United States)

    2007-04-10

    bullets. The present practice is to detect the presence of metal with an ANPSS-12 metal detector , and then probe with a short stick to identify the...experiment” describing how fusion operates is derived from considering how a soldier actually uses a metal detector . It is argued that the audible...a serious alternative to a stick, when used in concert with a metal detector . Recent breakthroughs in NQR physics, receiver design, and signal

  10. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung [Korea Atomic Energy Research Insitiute, Taejon (Korea, Republic of); Kim, Kyong Su [Chosun University, Kwangju (Korea, Republic of)

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks.

  11. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung [Korea Atomic Energy Research Insitiute, Taejon (Korea, Republic of); Kim, Kyong Su [Chosun University, Kwangju (Korea, Republic of)

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks.

  12. Nuclear and Atomic Methods of Mine Detection

    Science.gov (United States)

    1991-11-01

    has been developing various applications of nuclear magnetic resonance (NMR) and nuclear quadrupole resonance ( NQR ) in which the ultra-sensitive...and specific detection of military explosives and proposed that the technique of longitudinal magnetic resonance, in which the NMR and NQR resonances...magnetic fields, and the development of very fast gas chromatography and tandem mass spectrometers has had a major, impact on the potential for rapid

  13. MESHLESS METHOD FOR 2D MIXED-MODE CRACK PROPAGATION BASED ON VORONOI CELL

    Institute of Scientific and Technical Information of China (English)

    LouLullang; ZengPan

    2003-01-01

    A meshless method integrated with linear elastic fracture mechanics (LEFM) is presented for 2D mixed-mode crack propagation analysis. The domain is divided automatically into sub-domains based on Voronoi cells, which are used for quadrature for the potential energy. The continuous crack propagation is simulated with an incremental crack-extension method which assumes a piecewise linear discretization of the unknown crack path. For each increment of the crack extension, the meshless method is applied to carry out a stress analysis of the cracked structure. The J-integral, which can be decomposed into mode I and mode II for mixed-mode crack, is used for the evaluation of the stress intensity factors (SIFs). The crack-propagation direction, predicted on an incremental basis, is computed by a criterion defined in terms of the SIFs. The flowchart of the proposed procedure is presented and two numerical problems are analyzed with this method. The meshless results agree well with the experimental ones, which validates the accuracy and efficiency of the method.

  14. Method of detecting and counting bacteria

    Science.gov (United States)

    Picciolo, G. L.; Chappelle, E. W. (Inventor)

    1976-01-01

    An improved method is provided for determining bacterial levels, especially in samples of aqueous physiological fluids. The method depends on the quantitative determination of bacterial adenosine triphosphate (ATP) in the presence of nonbacterial ATP. The bacterial ATP is released by cell rupture and is measured by an enzymatic bioluminescent assay. A concentration technique is included to make the method more sensitive. It is particularly useful where the fluid to be measured contains an unknown or low bacteria count.

  15. Mode identification using stochastic hybrid models with applications to conflict detection and resolution

    Science.gov (United States)

    Naseri Kouzehgarani, Asal

    2009-12-01

    Most models of aircraft trajectories are non-linear and stochastic in nature; and their internal parameters are often poorly defined. The ability to model, simulate and analyze realistic air traffic management conflict detection scenarios in a scalable, composable, multi-aircraft fashion is an extremely difficult endeavor. Accurate techniques for aircraft mode detection are critical in order to enable the precise projection of aircraft conflicts, and for the enactment of altitude separation resolution strategies. Conflict detection is an inherently probabilistic endeavor; our ability to detect conflicts in a timely and accurate manner over a fixed time horizon is traded off against the increased human workload created by false alarms---that is, situations that would not develop into an actual conflict, or would resolve naturally in the appropriate time horizon-thereby introducing a measure of probabilistic uncertainty in any decision aid fashioned to assist air traffic controllers. The interaction of the continuous dynamics of the aircraft, used for prediction purposes, with the discrete conflict detection logic gives rise to the hybrid nature of the overall system. The introduction of the probabilistic element, common to decision alerting and aiding devices, places the conflict detection and resolution problem in the domain of probabilistic hybrid phenomena. A hidden Markov model (HMM) has two stochastic components: a finite-state Markov chain and a finite set of output probability distributions. In other words an unobservable stochastic process (hidden) that can only be observed through another set of stochastic processes that generate the sequence of observations. The problem of self separation in distributed air traffic management reduces to the ability of aircraft to communicate state information to neighboring aircraft, as well as model the evolution of aircraft trajectories between communications, in the presence of probabilistic uncertain dynamics as well

  16. Knock Detection in Spark Ignition Engines Base on Complementary Ensemble Empirical Mode Decomposition-Hilbert Transform

    Directory of Open Access Journals (Sweden)

    Fengrong Bi

    2016-01-01

    Full Text Available In spark ignition engines, knock onset limits the maximum spark advance. An inaccurate identification of this limit penalises the fuel conversion efficiency. Thus knock feature extraction is the key of closed-loop control of ignition in spark ignition engine. This paper reports an investigation of knock detection in spark ignition (SI engines using CEEMD-Hilbert transform based on the engine cylinder pressure signals and engine cylinder block vibration signals. Complementary Ensemble Empirical Mode Decomposition (CEEMD was used to decompose the signal and detect knock characteristic. Hilbert transform was used to analyze the frequency information of knock characteristic. The result shows that, for both of cylinder pressure signals and vibration signals, the CEEMD algorithm could extract the knock characteristic, and the Hilbert transform result shows that the energy of knock impact areas has the phenomenon of frequency concentration in both cylinder pressure signal and cylinder block vibration signal. At last, the knock window is then determined, based on which a new knock intensity evaluation factor K is propose, and it can accurately distinguish between heavy knock, light knock, and normal combustion three states.

  17. Range accuracy of photon heterodyne detection with laser pulse based on Geiger-mode APD.

    Science.gov (United States)

    Luo, Hanjun; Yuan, XiuHua; Zeng, Yanan

    2013-08-12

    In this paper, we propose a combined system of heterodyne detection with laser pulse and photon counting based on Geiger-mode avalanche photodiode (GM-APD) that is designed to achieve the range of remote non-cooperative target. Based on the heterodyne principle and assuming that the creation of primary electrons in GM-APD is Poisson-distributed, the range accuracy model is established. The factors that influence the range accuracy, namely pulse width, echo intensity, local oscillator (LO) intensity, noise, echo position, and beat frequency, are discussed. The results show that these six factors have significant influence on the range accuracy when the echo intensity is extremely weak. In case that the primary electrons of the echo signal are beyond 4, the pulse width and echo intensity are the main influence factors. It is also shown that the stronger echo intensity, narrower pulse width, low noise, large echo position, and small beat frequency produce higher range accuracy in a pulsed photon heterodyne detection system based on GM-APD.

  18. Electric Insulation Detection Method for High-voltage Insulators

    Directory of Open Access Journals (Sweden)

    Wang Jiajun

    2013-07-01

    Full Text Available The principle of partial discharge detection is that through partial bridged discharge under high voltage electric field, it detects the inner air-filled cavity of high-voltage insulators. And it is a nondestructive detection method based on discharge magnitude to judge the insulation quality. The detecting system that adopts the partial discharge detection is more rigorous than testing system for electricity products, which must have small discharge capacity and higher sensitivity. This paper describes the principles of partial discharge detection and analysis insulation detection.

  19. First-principle and data-driven model- based approach in rotating machinery failure mode detection

    Directory of Open Access Journals (Sweden)

    G. Wszołek

    2010-12-01

    Full Text Available Purpose: A major concern of modern diagnostics is the use of vibration or acoustic signals generated by a machine to reveal its operating conditions. This paper presents a method which allows to periodically obtain estimates of model eigenvalues represented by complex numbers. The method is intended to diagnose rotating machinery under transient conditions.Design/methodology/approach: The method uses a parametric data-driven model, the parameters of which are estimated using operational data.Findings: Experimental results were obtained with the use of a laboratory single-disc rotor system equipped with both sliding and hydrodynamic bearings. The test rig used allows measurements of data under normal, or reference, and malfunctioning operation, including oil instabilities, rub, looseness and unbalance, to be collected.Research limitations/implications: Numerical and experimental studies performed in order to validate the method are presented in the paper. Moreover, literature and industrial case studies are analyzed to better understand vibration modes of the rotor under abnormal operating conditions. Practical implications: A model of the test rig has been developed to verify the method proposed herein and to understand the results of the experiments. Hardware realization of the proposed method was implemented as a standalone operating module developed using the Texas Instruments TMS3200LF2407 Starter Kit.Originality/value: The parametric approach was proposed instead of nonparametric one towards diagnosing of rotating machinery.

  20. Analysis method and principle of dual-mode electro-mechanical variable transmission program

    Science.gov (United States)

    Li, Hongcai; Yan, Qingdong; Xiang, Changle; Wang, Weida

    2012-05-01

    Automotive industry, as an important pillar of the national economy, has been rapidly developing in recent years. But proplems such as energy comsumption and environmental pollution are posed at the same time. Electro-mechanical variable transmission system is considered one of avilable workarounds. It is brought forward a kind of design methods of dual-mode electro-mechanical variable transmission system rotational speed characteristics and dual-mode drive diagrams. With the motor operating behavior of running in four quadrants and the speed characteristics of the simple internal and external meshing single planetary gear train, four kinds of dual-mode electro-mechanical transmission system scheme are designed. And the velocity, torque and power characteristics of one of the programs are analyzed. The magnitude of the electric split-flow power is an important factor which influences the system performance, so in the parameters matching design, it needs to reduce the power needs under the first mode of the motor. The motor, output rotational speed range and the position of the mode switching point have relationships with the characteristics design of the planetary gear set. The analysis method is to provide a reference for hybrid vehicles' design. As the involved rotational speed and torque relationships are the natural contact of every part of transmission system, a theory basis of system program and performance analysis is provided.

  1. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images

    Directory of Open Access Journals (Sweden)

    Yongzheng Xu

    2016-08-01

    Full Text Available A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J and linear SVM classifier with HOG feature (HOG + SVM methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV images. As both V-J and HOG + SVM are sensitive to on-road vehicles’ in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians.

  2. Method for detecting software anomalies based on recurrence plot analysis

    OpenAIRE

    Michał Mosdorf

    2012-01-01

    Presented paper evaluates method for detecting software anomalies based on recurrence plot analysis of trace log generated by software execution. Described method for detecting software anomalies is based on windowed recurrence quantification analysis for selected measures (e.g. Recurrence rate - RR or Determinism - DET). Initial results show that proposed method is useful in detecting silent software anomalies that do not result in typical crashes (e.g. exceptions).

  3. Method for detecting software anomalies based on recurrence plot analysis

    Directory of Open Access Journals (Sweden)

    Michał Mosdorf

    2012-03-01

    Full Text Available Presented paper evaluates method for detecting software anomalies based on recurrence plot analysis of trace log generated by software execution. Described method for detecting software anomalies is based on windowed recurrence quantification analysis for selected measures (e.g. Recurrence rate - RR or Determinism - DET. Initial results show that proposed method is useful in detecting silent software anomalies that do not result in typical crashes (e.g. exceptions.

  4. Direct Path Detection Method in Indoor Location

    Institute of Scientific and Technical Information of China (English)

    HUA Hu; LI Zheng

    2006-01-01

    A search algorithm for the detection of a direct path signal in the presence of dense multipath in indoor environment using UWB is Proposed. This algorithm is based on signal correlation and differential coefficient. Statistical analysis of the algorithm is given out and computer simulation results are presented to validate the effectiveness of the algorithm.The results based on the algorithm proposed are compared with those based on Maximum Likelihood Estimator(MLE)and Peak Tracking(PT)in the simulation which shows that this algorithm achieves the highest accuracy in most cases and gives out relatively stable results in different Signal Noise Ratio(SNR).

  5. Correlation studies on surface particle detection methods

    Science.gov (United States)

    Peterson, Ronald V.; White, James C.

    1988-01-01

    The accurate determination of dust levels on optical surfaces is necessary to assess sensor system performance. A comparison study was made on several particle measurement methods including those based on direct imaging and light scattering. The effectiveness of removing the particles from the surface prior to determining particle size distributions was also assessed. These studies revealed that some methods, especially those requiring particle removal before analysis, are subject to large systematic errors affecting particle size distributions. Thus, an understanding of the particle measurement methods employed is necessary before any surface cleanliness or obstruction value assignments are accepted as true representations of an optical surface contamination condition.

  6. Coupling of non-conforming meshes in a component mode synthesis method

    NARCIS (Netherlands)

    Akcay-Perdahcioglu, D.; Doreille, M.; Boer, de A.; Ludwig, T.

    2013-01-01

    A common mesh refinement-based coupling technique is embedded into a component mode synthesis method, Craig–Bampton. More specifically, a common mesh is generated between the non-conforming interfaces of the coupled structures, and the compatibility constraints are enforced on that mesh via L2-minim

  7. A method for the estimation of p-mode parameters from averaged solar oscillation power spectra

    CERN Document Server

    Reiter, J; Kosovichev, A G; Schou, J; Scherrer, P H; Larson, T P

    2015-01-01

    A new fitting methodology is presented which is equally well suited for the estimation of low-, medium-, and high-degree mode parameters from $m$-averaged solar oscillation power spectra of widely differing spectral resolution. This method, which we call the "Windowed, MuLTiple-Peak, averaged spectrum", or WMLTP Method, constructs a theoretical profile by convolving the weighted sum of the profiles of the modes appearing in the fitting box with the power spectrum of the window function of the observing run using weights from a leakage matrix that takes into account both observational and physical effects, such as the distortion of modes by solar latitudinal differential rotation. We demonstrate that the WMLTP Method makes substantial improvements in the inferences of the properties of the solar oscillations in comparison with a previous method that employed a single profile to represent each spectral peak. We also present an inversion for the internal solar structure which is based upon 6,366 modes that we ha...

  8. AN INTELLIGENT NEURO-FUZZY TERMINAL SLIDING MODE CONTROL METHOD WITH APPLICATION TO ATOMIC FORCE MICROSCOPE

    Directory of Open Access Journals (Sweden)

    Seied Yasser Nikoo

    2016-11-01

    Full Text Available In this paper, a neuro-fuzzy fast terminal sliding mode control method is proposed for controlling a class of nonlinear systems with bounded uncertainties and disturbances. In this method, a nonlinear terminal sliding surface is firstly designed. Then, this sliding surface is considered as input for an adaptive neuro-fuzzy inference system which is the main controller. A proportinal-integral-derivative controller is also used to asist the neuro-fuzzy controller in order to improve the performance of the system at the begining stage of control operation. In addition, bee algorithm is used in this paper to update the weights of neuro-fuzzy system as well as the parameters of the proportinal-integral-derivative controller. The proposed control scheme is simulated for vibration control in a model of atomic force microscope system and the results are compared with conventional sliding mode controllers. The simulation results show that the chattering effect in the proposed controller is decreased in comparison with the sliding mode and the terminal sliding mode controllers. Also, the method provides the advantages of fast convergence and low model dependency compared to the conventional methods.

  9. Smoothing methods comparison for CMB E- and B-mode separation

    CERN Document Server

    Wang, Yi-Fan; Zhao, Wen

    2015-01-01

    The anisotropies of the B-mode polarization in the cosmic microwave background radiation play a crucial role for the study of the very early Universe. However, in the real observation, the mixture of the E-mode and B-mode can be caused by the partial sky surveys, which must be separated before applied to the cosmological explanation. The separation method developed by Smith (\\citealt{PhysRevD.74.083002}) has been widely adopted, where the edge of the top-hat mask should be smoothed to avoid the numerical errors. In this paper, we compare three different smoothing methods, and investigate the leakage residuals of the E-B mixture. We find that, if the less information loss is needed and the smaller region is smoothed in the analysis, the \\textit{sin}- and \\textit{cos}-smoothing methods are better. However, if we need a clean constructed B-mode map, the larger region around the mask edge should be smoothed. In this case, the \\textit{Gaussian}-smoothing method becomes much better. In addition, we find that the le...

  10. Active quenching circuit for single-photon detection with Geiger mode avalanche photodiodes.

    Science.gov (United States)

    Stipcević, Mario

    2009-03-20

    In this paper a novel construction of an active quenching circuit intended for single-photon detection is presented, along with a few original methods for its evaluation. The circuit has been combined with a standard avalanche photodiode C30902S to form a single-photon detector. This detector has a dead time of 39 ns, maximum random counting frequency of 14 MHz, small afterpulsing probability, an estimated peak detection efficiency of over 20%, and a dark count rate of less than 100 Hz. This simple and robust active quenching circuit can be built from off-the-shelf electronic components and is presented with the detailed schematic diagram.

  11. Marine Biotoxins: Occurrence, Toxicity, and Detection Methods

    Science.gov (United States)

    Asakawa, M.

    2017-04-01

    This review summarizes the role of marine organisms as vectors of marine biotoxins, and discusses the need for surveillance to protect public health and ensure the quality of seafood. I Paralytic shellfish poison (PSP) and PSP-bearing organisms-PSP is produced by toxic dinoflagellates species belonging to the genera Alexandrium, Gymnodinium, and Pyrodinium. Traditionally, PSP monitoring programs have only considered filter-feeding molluscs that concentrate these toxic algae, however, increasing attention is now being paid to higher-order predators that carry PSP, such as carnivorous gastropods and crustaceans. II. Tetrodotoxin (TTX) and TTX-bearing organisms - TTX is the most common natural marine toxin that causes food poisonings in Japan, and poses a serious public health risk. TTX was long believed to be present only in pufferfish. However, TTX was detected in the eggs of California newt Taricha torosa in 1964, and since then it has been detected in a wide variety of species belonging to several different phyla. In this study, the main toxic components in the highly toxic ribbon worm Cephalothrix simula and the greater blue-ringed octopus Hapalochlaena lunulata from Japan were purified and analysed.

  12. Correlation methods in fingerprint detection studies

    Energy Technology Data Exchange (ETDEWEB)

    Santer, B.D.; Wigley, T.M.L.; Jones, P.D. (Lawrence Livermore National Laboratory, Livermore, CA (United States))

    1993-07-01

    This investigation addresses two general issues regarding the role of pattern similarity statistics in greenhouse warming detection studies: normalization, and the relative merits of centered versus uncentered statistics. A pattern correlation statistic is used to search for the greenhouse warming signals predicted by five different models in the observed records of land and ocean surface temperature changes. Two forms of this statistic were computed: R(t), which makes use of non-normalized data, and R(t), which employs point-wise normalized data in order to focus the search on regions where the signal-to-noise ratio is large. While there are no trends in the R(t) time series, the time series of R(t) show large positive trends. However, it is not possible to infer from the R(t) results that the observed pattern of temperature change is, in fact, becoming increasingly similar to the model-predicted signal. It is shown that trends in R(t) must arise almost completely from the observed data, and cannot be an indicator of increasing observed data/signal similarity. The most informative pattern correlation statistic for detection purposes is R(t), the standard product-moment correlation coefficient between the observed and model fields. Our failure to find meaningful trends in R(t) may be due to the fact that the signal is being obscured by the background noise of natural variability, and/or because of incorrect model signals or sensitivities.

  13. Polarization sensitive optical coherence tomography detection method

    Energy Technology Data Exchange (ETDEWEB)

    Everett, M J; Sathyam, U S; Colston, B W; DaSilva, L B; Fried, D; Ragadio, J N; Featherstone, J D B

    1999-05-12

    This study demonstrates the potential of polarization sensitive optical coherence tomography (PS-OCT) for non-invasive in vivo detection and characterization of early, incipient caries lesions. PS-OCT generates cross-sectional images of biological tissue while measuring the effect of the tissue on the polarization state of incident light. Clear discrimination between regions of normal and demineralized enamel is first shown in PS-OCT images of bovine enamel blocks containing well-characterized artificial lesions. High-resolution, cross-sectional images of extracted human teeth are then generated that clearly discriminate between the normal and carious regions on both the smooth and occlusal surfaces. Regions of the teeth that appeared to be demineralized in the PS-OCT images were verified using histological thin sections examined under polarized light microscopy. The PS-OCT system discriminates between normal and carious regions by measuring the polarization state of the back-scattered 1310 nm light, which is affected by the state of demineralization of the enamel. Demineralization of enamel increases the scattereing coefficient, thus depolarizing the incident light. This study shows that PS-OCT has great potential for the detection, characterization, and monitoring of incipient caries lesions.

  14. The Study of Detecting Irregular Edge with Straight-Line Method

    Directory of Open Access Journals (Sweden)

    Muh-Don Hsiao

    2014-08-01

    Full Text Available This study’s main intention is to propose the best-fit line detection, Region of Interest (ROI detection and precision measuring method by using an object with an irregular edge in a high precision optical image. In general, an object with a smooth edge will actually display a very irregular and uneven gray scale distribution after being imaged by a high precision optical instrument, which may lead to a big problem if it is used in precision detection and measurement. Therefore, in this study we will individually propose the best-fit line detection, ROI detection conversion and the precision measuring method for irregular edges. The best-fit line detection is to propose two different best-fit line detection modes without affecting the computing time. The ROI detection method is to detect the region of most interest to the user and then to convert the regional line into a full-field image. For precision measurement, in this study we will propose a method for calculating the distance from the line to the edge and the distance between lines to achieve the measuring purpose.

  15. Detection of Outliers methods in medical studies

    Directory of Open Access Journals (Sweden)

    Babaee Gh

    2007-09-01

    Full Text Available   Background: An outlier is an observation that lies an abnormal distance from other values in a random sample from a population. Outliers sometimes deal with to abnormality in obtained results from collected data and information. known outlier data by researchers, physicians and other persons that work in medical fields and sciences is important and they must control data before getting result about outlier data, effect of them in information bias and how to remove & control to obtain minimum bias and exact data .in this paper we had trying by known technique and tests to control them and minimized the errors related to them.Methods: This paper has been done on 30 student's height in Tarbiat Modares University that measured by meter in smoothing area. We applied some methods such as; Z-test, Grub test and graphical methods to determine outliers. In this paper the advantage and disadvantage of methods were evaluated and finally compares with each other.Results: The above tests showed that the data values 153, 110 among collected data were outliers. All of the methods showed that the above data were outliers. Calculation quartiles and intermediate quartiles showed that the observations under 125 and upper 141 were mind outliers and if the observation under 119 and upper 147 is the sever outliers. According to upper situations the amounts of 110 and 153 is the sever outliers and resulted from all methods.Conclusion: The results showed that all methods were useful in determine outlier data and between them Quartiles were important to known severe and mild outliers. Also Grub test with p-Value is very useful to report outliers.

  16. Boundary flexibility method of component mode synthesis using static Ritz vectors

    Science.gov (United States)

    Abdallah, A. A.; Huckelbridge, A. A.

    1990-01-01

    A method of dynamic substructuring is presented which provides for the incorporation of a set of static Ritz vectors, referred to as boundary flexibility vectors, as a replacement and/or supplement to conventional eigenvectors in component mode synthesis. The suggested boundary flexibility Ritz vectors are generated by an extension of Wilson's load-dependent Ritz vector algorithm for transient dynamic analysis. The extended algorithm is not load-dependent, is applicable to both fixed-and free-interface components, and results in a general component mode synthesis model appropriate for any type of dynamic analysis.

  17. Low-Mode Conformational Search Method with Semiempirical Quantum Mechanical Calculations: Application to Enantioselective Organocatalysis.

    Science.gov (United States)

    Kamachi, Takashi; Yoshizawa, Kazunari

    2016-02-22

    A conformational search program for finding low-energy conformations of large noncovalent complexes has been developed. A quantitatively reliable semiempirical quantum mechanical PM6-DH+ method, which is able to accurately describe noncovalent interactions at a low computational cost, was employed in contrast to conventional conformational search programs in which molecular mechanical methods are usually adopted. Our approach is based on the low-mode method whereby an initial structure is perturbed along one of its low-mode eigenvectors to generate new conformations. This method was applied to determine the most stable conformation of transition state for enantioselective alkylation by the Maruoka and cinchona alkaloid catalysts and Hantzsch ester hydrogenation of imines by chiral phosphoric acid. Besides successfully reproducing the previously reported most stable DFT conformations, the conformational search with the semiempirical quantum mechanical calculations newly discovered a more stable conformation at a low computational cost.

  18. Signal classification method based on data mining for multi-mode radar

    Institute of Scientific and Technical Information of China (English)

    Qiang Guo; Pulong Nan; Jian Wan

    2016-01-01

    For the multi-mode radar working in the modern elec-tronic battlefield, different working states of one single radar are prone to being classified as multiple emitters when adopting traditional classification methods to process intercepted signals, which has a negative effect on signal classification. A classification method based on spatial data mining is presented to address the above chal enge. Inspired by the idea of spatial data mining, the classification method applies nuclear field to depicting the distribu-tion information of pulse samples in feature space, and digs out the hidden cluster information by analyzing distribution characteristics. In addition, a membership-degree criterion to quantify the correla-tion among al classes is established, which ensures classification accuracy of signal samples. Numerical experiments show that the presented method can effectively prevent different working states of multi-mode emitter from being classified as several emitters, and achieve higher classification accuracy.

  19. Detection methods and performance criteria for genetically modified organisms.

    Science.gov (United States)

    Bertheau, Yves; Diolez, Annick; Kobilinsky, André; Magin, Kimberly

    2002-01-01

    Detection methods for genetically modified organisms (GMOs) are necessary for many applications, from seed purity assessment to compliance of food labeling in several countries. Numerous analytical methods are currently used or under development to support these needs. The currently used methods are bioassays and protein- and DNA-based detection protocols. To avoid discrepancy of results between such largely different methods and, for instance, the potential resulting legal actions, compatibility of the methods is urgently needed. Performance criteria of methods allow evaluation against a common standard. The more-common performance criteria for detection methods are precision, accuracy, sensitivity, and specificity, which together specifically address other terms used to describe the performance of a method, such as applicability, selectivity, calibration, trueness, precision, recovery, operating range, limit of quantitation, limit of detection, and ruggedness. Performance criteria should provide objective tools to accept or reject specific methods, to validate them, to ensure compatibility between validated methods, and be used on a routine basis to reject data outside an acceptable range of variability. When selecting a method of detection, it is also important to consider its applicability, its field of applications, and its limitations, by including factors such as its ability to detect the target analyte in a given matrix, the duration of the analyses, its cost effectiveness, and the necessary sample sizes for testing. Thus, the current GMO detection methods should be evaluated against a common set of performance criteria.

  20. Development of detection methods for irradiated foods - Detection method for radiolytic products of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Kim, Sun Min; Park, Eun Ryong; Lee, Hae Jung; Kim, Eun Ah; Jo, Jung Ok [Chosun University, Kwangju (Korea)

    1999-04-01

    Meat (beef, pork, chicken) and nut (sesame, perilla, black sesame, peanut) were irradiated with /sup 60/Co gamma-ray. A process to detect radiation-induced hydrocarbons and 2-alkylcyclobutanones includes the extraction of fat from meat and nut, separation of hydrocarbons and 2-alkylcyclobutanones with a florisil column and identification of GC/MS methods. Concentrations of the produced hydrocarbons and 2-alkylcyclobutanones tended to increase linearly with the dose levels of irradiation in beef, pork and chicken, while concentrations of radiation-induced hydrocarbons were different individually at the same dose level. In meat, hydrocarbons and 2-alkylcyclobutanones originated from oleic acid were found in a large amount. The concentrations of radiation-induced hydrocarbons were relatively constant during 16 weeks. In nut, hydrocarbons originated from oleic acid and linoleic acid were the major compounds whereas results of perilla was similar to meat. Radiation-induced hydrocarbons were increased linearly with the irradiation dose and remarkably detected at 0.5 kGy and over. 44 refs., 30 figs., 14 tabs. (Author)

  1. Dynamic substructuring by the boundary flexibility vector method of component mode synthesis. Ph.D. Thesis

    Science.gov (United States)

    Abdallah, Ayman Ahmed

    1990-01-01

    Component mode synthesis (CMS) is a method of dynamic analysis, for structures having a large number of degrees of freedom (DOF). These structures often required lengthy computer CPU time and large computer memory resources, if solved directly by the finite-element method (FEM). In CMS, the structure is divided into independent components in which the DOF are defined by a set of generalized coordinates defined by displacement shapes. The number of the generalized coordinates are much less than the original number of physical DOF, in the component. The displacement shapes are used to transform the component property matrices and any applied external loads, to a reduced system of coordinates. Reduced system property matrices are assembled, and any type of dynamic analysis is carried out in the reduced coordinate system. Any obtained results are back transformed to the original component coordinate systems. In all conventional methods of CMS, the mode shapes used for components are dynamic mode shapes, supplemented by static deflected shapes. Historically, all the dynamic mode shapes used in conventional CMS are the natural modes (eigenvectors) of components. A new method of CMS, namely the boundary flexibility vector method of CMS, is presented. The method provides for the incorporation of a set of static Ritz vectors, referred to as boundary flexibility vectors, as a replacement and/or supplement to conventional eigenvectors, as displacement shapes for components. The generation of these vectors does not require the solution of a costly eigenvalue problem, as in the case of natural modes in conventional CMS, and hence a substantial saving in CPU time can be achieved. The boundary flexibility vectors are generated from flexibility (or stiffness) properties of components. The formulation presented is for both free and fixed-interface components, and for both the free and forced vibration problems. Free and forced vibration numerical examples are presented to verify

  2. Methods for detection of ataxia telangiectasia mutations

    Energy Technology Data Exchange (ETDEWEB)

    Gatti, Richard A.

    2005-10-04

    The present invention is directed to a method of screening large, complex, polyexonic eukaryotic genes such as the ATM gene for mutations and polymorphisms by an improved version of single strand conformation polymorphism (SSCP) electrophoresis that allows electrophoresis of two or three amplified segments in a single lane. The present invention also is directed to new mutations and polymorphisms in the ATM gene that are useful in performing more accurate screening of human DNA samples for mutations and in distinguishing mutations from polymorphisms, thereby improving the efficiency of automated screening methods.

  3. A Mode-Accelerated XXr (MAX) method for complex structures with large blends

    Science.gov (United States)

    Gan, Yiqian; Mayer, John L.; D'Souza, Kiran X.; Epureanu, Bogdan I.

    2017-09-01

    Various reduced order models have been proposed for characterizing cyclic symmetric structures with complex geometry and varying material properties that are subject to complex boundary or loading conditions. Small variations can be represented as small mass or stiffness mistuning. Techniques developed to handle such variations rely on the fact that the modes of the system can be accurately approximated using a linear combination of modes of the healthy/nominal system. Such approximations are valid in regions of high modal density, but they break down when variations are large or geometric changes are present. To address this challenge, a novel method is presented to predict the vibration response of cyclic symmetric structures with large geometric changes due to damage in the form of missing material (blends). The central idea of the new approach is an extension of the XXr method for cracked structures. The XXr method was developed for modeling small mistuning and large cracks. That method is extended in this work to handle large blends. In addition, a specialized component mode synthesis is combined with the extended XXr method to maintain accuracy. Also, unique to the proposed novel method is a technique to accelerate the convergence of the order reduction, and thus obtain very low order models. These low order models provide excellent computational speed and effectiveness while maintaining accuracy. Therefore, the method can be applied to highly refined, realistic models of industrial size. To demonstrate the proposed mode-accelerated XXr method, the effects of large blends on the response of a bladed disk are investigated.

  4. Thermal History Devices, Systems For Thermal History Detection, And Methods For Thermal History Detection

    KAUST Repository

    Caraveo Frescas, Jesus Alfonso

    2015-05-28

    Embodiments of the present disclosure include nanowire field-effect transistors, systems for temperature history detection, methods for thermal history detection, a matrix of field effect transistors, and the like.

  5. Detection limits of tidal-wetland sequences to identify variable rupture modes of megathrust earthquakes

    Science.gov (United States)

    Shennan, Ian; Garrett, Ed; Barlow, Natasha

    2016-10-01

    Recent paleoseismological studies question whether segment boundaries identified for 20th and 21st century great, >M8, earthquakes persist through multiple earthquake cycles or whether smaller segments with different boundaries rupture and cause significant hazards. The smaller segments may include some currently slipping rather than locked. In this review, we outline general principles regarding indicators of relative sea-level change in tidal wetlands and the conditions in which paleoseismic indicators must be distinct from those resulting from non-seismic processes. We present new evidence from sites across southcentral Alaska to illustrate different detection limits of paleoseismic indicators and consider alternative interpretations for marsh submergence and emergence. We compare predictions of coseismic uplift and subsidence derived from geophysical models of earthquakes with different rupture modes. The spatial patterns of agreement and misfits between model predictions and quantitative reconstructions of coseismic submergence and emergence suggest that no earthquake within the last 4000 years had a pattern of rupture the same as the Mw 9.2 Alaska earthquake in 1964. From the Alaska examples and research from other subduction zones we suggest that If we want to understand whether a megathrust ruptures in segments of variable length in different earthquakes, we need to be site-specific as to what sort of geological-based criteria eliminate the possibility of a particular rupture mode in different earthquakes. We conclude that coastal paleoseismological studies benefit from a methodological framework that employs rigorous evaluation of five essential criteria and a sixth which may be very robust but only occur at some sites: 1 - lateral extent of peat-mud or mud-peat couplets with sharp contacts; 2 - suddenness of submergence or emergence, and replicated within each site; 3 - amount of vertical motion, quantified with 95% error terms and replicated within each

  6. A training method for locomotion mode prediction using powered lower limb prostheses.

    Science.gov (United States)

    Young, Aaron J; Simon, Ann M; Hargrove, Levi J

    2014-05-01

    Recently developed lower-limb prostheses are capable of actuating the knee and ankle joints, allowing amputees to perform advanced locomotion modes such as step-over-step stair ascent and walking on sloped surfaces. However, transitions between these locomotion modes and walking are neither automatic nor seamless. This study describes methods for construction and training of a high-level intent recognition system for a lower-limb prosthesis that provides natural transitions between walking, stair ascent, stair descent, ramp ascent, and ramp descent. Using mechanical sensors onboard a powered prosthesis, we collected steady-state and transition data from six transfemoral amputees while the five locomotion modes were performed. An intent recognition system built using only mechanical sensor data was 84.5% accurate using only steady-state training data. Including training data collected while amputees performed seamless transitions between locomotion modes improved the overall accuracy rate to 93.9%. Training using a single analysis window at heel contact and toe off provided higher recognition accuracy than training with multiple analysis windows. This study demonstrates the capability of an intent recognition system to provide automatic, natural, and seamless transitions between five locomotion modes for transfemoral amputees using powered lower limb prostheses.

  7. Method of Detecting Coliform Bacteria from Reflected Light

    Science.gov (United States)

    Vincent, Robert K. (Inventor)

    2014-01-01

    The present invention relates to a method of detecting coliform bacteria in water from reflected light, and also includes devices for the measurement, calculation and transmission of data relating to that method.

  8. New Atomic Methods for Dark Matter Detection

    Science.gov (United States)

    Roberts, Benjamin; Stadnik, Yevgeny; Dzuba, Vladimir; Flambaum, Victor; Leefer, Nathan; Budker, Dmitry

    2015-05-01

    We propose to exploit P and T violating effects in atoms, nuclei, and molecules to search for dark matter (eg axions) and various other cosmic fields. We perform calculations of electric dipole moments (EDMs) that a dark matter field would induce in atoms. Crucially, the effects we consider here are linear in the small parameter that quantifies the dark matter interaction strength; most current searches rely on effects that are at least quadratic in this parameter. The induced oscillating EDMs have the potential to be measured with very high accuracy, and experimental techniques in this field are evolving fast. Pairs of closely spaced opposite parity levels that are found in diatomic molecules will also lead to a significant enhancement in these effects. We are also interested in a possible explanation for the anomalous DAMA dark matter detection results based on DM-electron scattering. Our calculations may provide a possible mechanism for dark matter induced ionisation modulations that are not ruled out by other experiments. Alternatively, they could further reduce the available parameter space for certain dark matter models.

  9. A-mode ultrasound-based intra-femoral bone cement detection and 3D reconstruction in RTHR.

    Science.gov (United States)

    Heger, Stefan; Mumme, Thorsten; Sellei, Richard; De La Fuente, Matias; Wirtz, Dieter-C; Radermacher, Klaus

    2007-05-01

    Due to the difficulty of determining the 3D boundary of the cement-bone interface in Revision Total Hip Replacement (RTHR), the removal of the distal intra-femoral bone cement can be a time-consuming and risky operation. Within the framework of computer- and robot-assisted cement removal, the principles and first results of an automatic detection and 3D surface reconstruction of the cement-bone boundary using A-mode ultrasound are described. Sound propagation time and attenuation of cement were determined considering different techniques for the preparation of bone cement, such as the use of a vacuum system (Optivac, Biomet). A laboratory setup using a rotating, standard 5-MHz transducer was developed. The prototype enables scanning of bisected cement-prepared femur samples in a 90 degrees rotation range along their rotation axis. For system evaluation ex vivo, the distal femur of a human cadaver was prepared with bone cement and drilled (Ø 10 mm) to simulate the prosthesis cavity in a first approximation. The sample was cut in half and CT scanned (0.24 mm resolution; 0.5 mm distance; 0.5 mm thickness), and 3D voxel models of the manually segmented bone cement were reconstructed, providing the ground truth. Afterwards, 90 degrees segments of each ex-vivo sample were scanned by the A-mode ultrasound system. To obtain better ultrasound penetration, we used coded signal excitation and pulse compression filtering. A-mode ultrasound signal detection, filtering and segmentation were accomplished fully automatically. Subsequently, 3D voxel models of each sample were calculated. Accuracy evaluation of the measured ultrasound data was performed by ICP matching of each ultrasound dataset ( approximately 8000 points) to the corresponding CT dataset and calculation of the residual median distance error between the corresponding datasets. Prior to each ICP matching, an initial pre-registration was calculated using prominent landmarks in the corresponding datasets. This method

  10. An Optimal Method for Detecting Internal and External Intrusion in MANET

    Science.gov (United States)

    Rafsanjani, Marjan Kuchaki; Aliahmadipour, Laya; Javidi, Mohammad M.

    Mobile Ad hoc Network (MANET) is formed by a set of mobile hosts which communicate among themselves through radio waves. The hosts establish infrastructure and cooperate to forward data in a multi-hop fashion without a central administration. Due to their communication type and resources constraint, MANETs are vulnerable to diverse types of attacks and intrusions. In this paper, we proposed a method for prevention internal intruder and detection external intruder by using game theory in mobile ad hoc network. One optimal solution for reducing the resource consumption of detection external intruder is to elect a leader for each cluster to provide intrusion service to other nodes in the its cluster, we call this mode moderate mode. Moderate mode is only suitable when the probability of attack is low. Once the probability of attack is high, victim nodes should launch their own IDS to detect and thwart intrusions and we call robust mode. In this paper leader should not be malicious or selfish node and must detect external intrusion in its cluster with minimum cost. Our proposed method has three steps: the first step building trust relationship between nodes and estimation trust value for each node to prevent internal intrusion. In the second step we propose an optimal method for leader election by using trust value; and in the third step, finding the threshold value for notifying the victim node to launch its IDS once the probability of attack exceeds that value. In first and third step we apply Bayesian game theory. Our method due to using game theory, trust value and honest leader can effectively improve the network security, performance and reduce resource consumption.

  11. Leakage detection in galvanized iron pipelines using ensemble empirical mode decomposition analysis

    Science.gov (United States)

    Amin, Makeen; Ghazali, M. Fairusham

    2015-05-01

    There are many numbers of possible approaches to detect leaks. Some leaks are simply noticeable when the liquids or water appears on the surface. However many leaks do not find their way to the surface and the existence has to be check by analysis of fluid flow in the pipeline. The first step is to determine the approximate position of leak. This can be done by isolate the sections of the mains in turn and noting which section causes a drop in the flow. Next approach is by using sensor to locate leaks. This approach are involves strain gauge pressure transducers and piezoelectric sensor. the occurrence of leaks and know its exact location in the pipeline by using specific method which are Acoustic leak detection method and transient method. The objective is to utilize the signal processing technique in order to analyse leaking in the pipeline. With this, an EEMD method will be applied as the analysis method to collect and analyse the data.

  12. High-Speed Spindle Fault Diagnosis with the Empirical Mode Decomposition and Multiscale Entropy Method

    Directory of Open Access Journals (Sweden)

    Nan-Kai Hsieh

    2015-04-01

    Full Text Available The root mean square (RMS value of a vibration signal is an important indicator used to represent the amplitude of vibrations in evaluating the quality of high-speed spindles. However, RMS is unable to detect a number of common fault characteristics that occur prior to bearing failure. Extending the operational life and quality of spindles requires reliable fault diagnosis techniques for the analysis of vibration signals from three axes. This study used empirical mode decomposition to decompose signals into intrinsic mode functions containing a zero-crossing rate and energy to represent the characteristics of rotating elements. The MSE curve was then used to identify a number of characteristic defects. The purpose of this research was to obtain vibration signals along three axes with the aim of extending the operational life of devices included in the product line of an actual spindle manufacturing company.

  13. Two methods for estimating aeroelastic damping of operational wind turbine modes from experiments

    DEFF Research Database (Denmark)

    Hansen, Morten Hartvig; Thomsen, Kenneth; Fuglsang, Peter;

    2006-01-01

    on stochastic subspace identification, where a linear model of the turbine is estimated alone from measured response signals by assuming that the ambient excitation from turbulence is random in time and space. Although the assumption is not satisfied, this operational modal analysis method can handle......The theory and results of two experimental methods for estimating the modal damping of a wind turbine during operation are presented. Estimations of the aeroelastic damping of the operational turbine modes (including the effects of the aerodynamic forces) give a quantitative view of the stability...... characteristics of the turbine. In the first method the estimation of modal damping is based on the assumption that a turbine mode can be excited by a harmonic force at its natural frequency, whereby the decaying response after the end of excitation gives an estimate of the damping. Simulations and experiments...

  14. A robust extension to the triple plane pressure mode matching method by filtering convective perturbations

    CERN Document Server

    Wohlbrandt, Attila; Guérin, Sébastien

    2015-01-01

    Time-periodic CFD simulations are widely used to investigate turbomachinery components. The triple-plane pressure mode matching method (TPP) developed by Ovenden and Rienstra extracts the acoustic part in such simulations. Experience shows that this method is subject to significant errors when the amplitude of pseudo-sound is high compared to sound. Pseudo-sound are unsteady pressure fluctuations with a convective character. The presented extension to the TPP improves the splitting between acoustics and the rest of the unsteady flow field. The method is simple: i) the acoustic eigenmodes are analytically determined for a uniform mean flow as in the original TPP; ii) the suggested model for convective pressure perturbations uses the convective wavenumber as axial wavenumber and the same orthogonal radial shape functions as for the acoustic modes. The reliability is demonstrated on the simulation data of a low-pressure fan. As acoustic and convective perturbations are separated, the accuracy of the results incr...

  15. Application of empirical mode decomposition method for characterization of random vibration signals

    Directory of Open Access Journals (Sweden)

    Setyamartana Parman

    2016-07-01

    Full Text Available Characterization of finite measured signals is a great of importance in dynamical modeling and system identification. This paper addresses an approach for characterization of measured random vibration signals where the approach rests on a method called empirical mode decomposition (EMD. The applicability of proposed approach is tested in one numerical and experimental data from a structural system, namely spar platform. The results are three main signal components, comprising: noise embedded in the measured signal as the first component, first intrinsic mode function (IMF called as the wave frequency response (WFR as the second component and second IMF called as the low frequency response (LFR as the third component while the residue is the trend. Band-pass filter (BPF method is taken as benchmark for the results obtained from EMD method.

  16. Sensitive detection of n-alkanes using a mixed ionization mode proton-transfer-reaction mass spectrometer

    Science.gov (United States)

    Amador-Muñoz, Omar; Misztal, Pawel K.; Weber, Robin; Worton, David R.; Zhang, Haofei; Drozd, Greg; Goldstein, Allen H.

    2016-11-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) is a technique that is widely used to detect volatile organic compounds (VOCs) with proton affinities higher than water. However, n-alkanes generally have a lower proton affinity than water and therefore proton transfer (PT) by reaction with H3O+ is not an effective mechanism for their detection. In this study, we developed a method using a conventional PTR-MS to detect n-alkanes by optimizing ion source and drift tube conditions to vary the relative amounts of different primary ions (H3O+, O2+, NO+) in the reaction chamber (drift tube). There are very few studies on O2+ detection of alkanes and the mixed mode has never been proposed before. We determined the optimum conditions and the resulting reaction mechanisms, allowing detection of n-alkanes from n-pentane to n-tridecane. These compounds are mostly emitted by evaporative/combustion process from fossil fuel use. The charge transfer (CT) mechanism observed with O2+ was the main reaction channel for n-heptane and longer n-alkanes, while for n-pentane and n-hexane the main reaction channel was hydride abstraction (HA). Maximum sensitivities were obtained at low E / N ratios (83 Td), low water flow (2 sccm) and high O2+ / NO+ ratios (Uso = 180 V). Isotopic 13C contribution was taken into account by subtracting fractions of the preceding 12C ion signal based on the number of carbon atoms and the natural abundance of 13C (i.e., 5.6 % for n-pentane and 14.5 % for n-tridecane). After accounting for isotopic distributions, we found that PT cannot be observed for n-alkanes smaller than n-decane. Instead, protonated water clusters of n-alkanes (M ṡ H3O+) species were observed with higher abundance using lower O2+ and higher water cluster fractions. M ṡ H3O+ species are probably the source for the M + H+ species observed from n-decane to n-tridecane. Normalized sensitivities to O2+ or to the sum of O2++ NO+ were determined to be a good metric with which to

  17. Sliding mode observer based incipient sensor fault detection with application to high-speed railway traction device.

    Science.gov (United States)

    Zhang, Kangkang; Jiang, Bin; Yan, Xing-Gang; Mao, Zehui

    2016-07-01

    This paper considers incipient sensor fault detection issue for a class of nonlinear systems with "observer unmatched" uncertainties. A particular fault detection sliding mode observer is designed for the augmented system formed by the original system and incipient sensor faults. The designed parameters are obtained using LMI and line filter techniques to guarantee that the generated residuals are robust to uncertainties and that sliding motion is not destroyed by faults. Then, three levels of novel adaptive thresholds are proposed based on the reduced order sliding mode dynamics, which effectively improve incipient sensor faults detectability. Case study of on the traction system in China Railway High-speed is presented to demonstrate the effectiveness of the proposed incipient senor faults detection schemes.

  18. A correlation method of detecting and estimating interactions of QTLs

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    More and more studies demonstrate that a great deal of interactions among the quantitative trait loci (QTLs) are far more than those detected by single markers. A correlation method was proposed for estimating the interactions of multiple QTLs detected by multi-markers in several mapping populations. Genetic implication of this method and usage were discussed.

  19. A NEW METHOD OF MOVING OBJECT DETECTION AND SHADOW REMOVING

    Institute of Scientific and Technical Information of China (English)

    Hu Fuyuan; Zhang Yanning; Yao Lan; Sun Jinqiu

    2007-01-01

    This paper presents an adaptive method of objects and shadows detection in video streams.Models of background are firstly set up and adaptively updated in Hue Saturation Intensity (HSI)color space to detect motion regions. Then, detection errors are dealt with by motion continuity and velocity consistency. Finally, cast shadows are removed by the generic properties of luminance,chrominance and gradient density. Experimental results and their evaluation are presented to verify the effectiveness of this new method.

  20. Localized surface plasmon resonance mercury detection system and methods

    Energy Technology Data Exchange (ETDEWEB)

    James, Jay; Lucas, Donald; Crosby, Jeffrey Scott; Koshland, Catherine P.

    2016-03-22

    A mercury detection system that includes a flow cell having a mercury sensor, a light source and a light detector is provided. The mercury sensor includes a transparent substrate and a submonolayer of mercury absorbing nanoparticles, e.g., gold nanoparticles, on a surface of the substrate. Methods of determining whether mercury is present in a sample using the mercury sensors are also provided. The subject mercury detection systems and methods find use in a variety of different applications, including mercury detecting applications.

  1. Method for detecting trace impurities in gases

    Science.gov (United States)

    Freund, S.M.; Maier, W.B. II; Holland, R.F.; Beattie, W.H.

    A technique for considerably improving the sensitivity and specificity of infrared spectrometry as applied to quantitative determination of trace impurities in various carrier or solvent gases is presented. A gas to be examined for impurities is liquefied and infrared absorption spectra of the liquid are obtained. Spectral simplification and number densities of impurities in the optical path are substantially higher than are obtainable in similar gas-phase analyses. Carbon dioxide impurity (approx. 2 ppM) present in commercial Xe and ppM levels of Freon 12 and vinyl chloride added to liquefied air are used to illustrate the method.

  2. Delamination detection using methods of computational intelligence

    Science.gov (United States)

    Ihesiulor, Obinna K.; Shankar, Krishna; Zhang, Zhifang; Ray, Tapabrata

    2012-11-01

    Abstract Reliable delamination prediction scheme is indispensable in order to prevent potential risks of catastrophic failures in composite structures. The existence of delaminations changes the vibration characteristics of composite laminates and hence such indicators can be used to quantify the health characteristics of laminates. An approach for online health monitoring of in-service composite laminates is presented in this paper that relies on methods based on computational intelligence. Typical changes in the observed vibration characteristics (i.e. change in natural frequencies) are considered as inputs to identify the existence, location and magnitude of delaminations. The performance of the proposed approach is demonstrated using numerical models of composite laminates. Since this identification problem essentially involves the solution of an optimization problem, the use of finite element (FE) methods as the underlying tool for analysis turns out to be computationally expensive. A surrogate assisted optimization approach is hence introduced to contain the computational time within affordable limits. An artificial neural network (ANN) model with Bayesian regularization is used as the underlying approximation scheme while an improved rate of convergence is achieved using a memetic algorithm. However, building of ANN surrogate models usually requires large training datasets. K-means clustering is effectively employed to reduce the size of datasets. ANN is also used via inverse modeling to determine the position, size and location of delaminations using changes in measured natural frequencies. The results clearly highlight the efficiency and the robustness of the approach.

  3. Materials, instrumentation and techniques for the detection of Special Nuclear Material and Radioactive Sources: EU project MODES SNM

    OpenAIRE

    2015-01-01

    MODES SNM project is part of the European Union effort to promote research and innovation in strategic topics; it includes seven participants from five different countries. The project aimed to carry out technical research in order to develop a prototype for a mobile, modular detection system for radioactive sources and Special Nuclear Materials (SNM). The project’s main goal was to deliver a tested prototype of a modular mobile system capable of passively detecting weak or shielded radioacti...

  4. Detection efficiencies of 226Ra and 232Th in different modes of counting of the PRIPYAT-2M spectrometer

    Directory of Open Access Journals (Sweden)

    Antović Nevenka M.

    2009-01-01

    Full Text Available Detection efficiencies of 226Ra and 232Th decay products, as well as corresponding minimum detectable activities in different modes of counting of the PRIPYAT-2M spectrometer (integral, when all pulses - coincident and non-coincident, are counted; non-coincident, when only non-coincident pulses are counted; coincident, when coincident pulses of multiplicity from 2 to 6 are counted, in energy ranges of 200 keV to 2000 keV and 300 keV to 3000 keV are presented here. It has been shown that the mode of double coincidences is the optimum one for measuring radium and thorium activity. In this mode of counting, the sensitivity of the spectrometer is the highest.

  5. Method And Apparatus For Detecting Chemical Binding

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Miller, Thomasin C. (Los Alamos, NM); Wells, Cyndi A. (Los Alamos, NM)

    2005-02-22

    The method for screening binding between a target binder and potential pharmaceutical chemicals involves sending a solution (preferably an aqueous solution) of the target binder through a conduit to a size exclusion filter, the target binder being too large to pass through the size exclusion filter, and then sending a solution of one or more potential pharmaceutical chemicals (preferably an aqueous solution) through the same conduit to the size exclusion filter after target binder has collected on the filter. The potential pharmaceutical chemicals are small enough to pass through the filter. Afterwards, x-rays are sent from an x-ray source to the size exclusion filter, and if the potential pharmaceutical chemicals form a complex with the target binder, the complex produces an x-ray fluorescence signal having an intensity that indicates that a complex has formed.

  6. Method and apparatus for detecting chemical binding

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Miller, Thomasin C. (Los Alamos, NM); Wells, Cyndi A. (Los Alamos, NM)

    2007-07-10

    The method for screening binding between a target binder and potential pharmaceutical chemicals involves sending a solution (preferably an aqueous solution) of the target binder through a conduit to a size exclusion filter, the target binder being too large to pass through the size exclusion filter, and then sending a solution of one or more potential pharmaceutical chemicals (preferably an aqueous solution) through the same conduit to the size exclusion filter after target binder has collected on the filter. The potential pharmaceutical chemicals are small enough to pass through the filter. Afterwards, x-rays are sent from an x-ray source to the size exclusion filter, and if the potential pharmaceutical chemicals form a complex with the target binder, the complex produces an x-ray fluorescence signal having an intensity that indicates that a complex has formed.

  7. OPGW Corrosion Detection Using Nondestructive Test Method

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, J.K.; Yoon, G.G.; Kang, J.W.; Yang, H.W. [Hanyang University, Seoul (Korea, Republic of)

    1998-02-01

    This paper deals with some characteristics of a nondestructive eddy current detector to measure OPGW(composite overhead ground wire with optical fiber) corrosion. This detector is designed to automatically run on OPGW and to continuously inspect the corrosion of the line. The impedance of the eddy coil changing by any corrosion phenomenon of OPGW is analyzed. Several performances of the detector are described and experimental procedures and test results are also given. As a result, it is shown that the implemented detector can be measured some quantitative data for crack, broken wires or severe deteriorations in OPGW. This nondestructive test method would be applied to improve the reliability and efficiency of transmission lines in service. (author). 5 refs., 9 figs., 2 tabs.

  8. Automatic trip and mode detection with MoveSmarter: first results from the Dutch Mobile Mobility Panel

    NARCIS (Netherlands)

    Geurs, K.T.; Thomas, T.; Bijlsma, M.; Douhou, S.

    2015-01-01

    This paper describes the performance of a smartphone app called MoveSmarter to automatically detect departure and arrival times, trip origins and destinations, transport modes, and travel purposes. The app is used in a three-year smartphone-based prompted-recall panel survey in which about 600 smart

  9. Automatic trip and mode detection with MoveSmarter: first results from the Dutch Mobile Mobility Panel

    NARCIS (Netherlands)

    Geurs, Karst Teunis; Thomas, Tom; Bijlsma, M.; Douhou, S.

    2015-01-01

    This paper describes the performance of a smartphone app called MoveSmarter to automatically detect departure and arrival times, trip origins and destinations, transport modes, and travel purposes. The app is used in a three-year smartphone-based prompted-recall panel survey in which about 600

  10. CHANGE DETECTION BY FUSING ADVANTAGES OF THRESHOLD AND CLUSTERING METHODS

    Directory of Open Access Journals (Sweden)

    M. Tan

    2017-09-01

    Full Text Available In change detection (CD of medium-resolution remote sensing images, the threshold and clustering methods are two kinds of the most popular ones. It is found that the threshold method of the expectation maximum (EM algorithm usually generates a CD map including many false alarms but almost detecting all changes, and the fuzzy local information c-means algorithm (FLICM obtains a homogeneous CD map but with some missed detections. Therefore, we aim to design a framework to improve CD results by fusing the advantages of threshold and clustering methods. Experimental results indicate the effectiveness of the proposed method.

  11. Weak Signal Frequency Detection Method Based on Generalized Duffing Oscillator

    Institute of Scientific and Technical Information of China (English)

    SHI Si-Hong; YUAN Yong; WANG Hui-Qi; LUO Mao-Kang

    2011-01-01

    @@ The sensitive characteristic to the initial value of chaos system sufficiently demonstrates the superiority in weak signal parameters detection.Analyzing the current chaos-based frequency detection method, a novel generalized Duffing equation is proposed to detect weak signal frequency.By choosing a suitable adjusting factor, when the outside driving force frequency is equal to that of the detected signal, the generalized Duffing oscillator is in great period state, which can obtain the frequency information of the detected signal.The simulation results indicate this method is rapidly convenient and shows better accuracy.%The sensitive characteristic to the initial value of chaos system sufficiently demonstrates the superiority in weak signal parameters detection. Analyzing the current chaos-based frequency detection method, a novel generalized Duffing equation is proposed to detect weak signal frequency. By choosing a suitable adjusting factor, when the outside driving force frequency is equal to that of the detected signal, the generalized Duffing oscillator is in great period state, which can obtain the frequency information of the detected signal. The simulation results indicate this method is rapidly convenient and shows better accuracy.

  12. Reliably Detectable Flaw Size for NDE Methods that Use Calibration

    Science.gov (United States)

    Koshti, Ajay M.

    2017-01-01

    Probability of detection (POD) analysis is used in assessing reliably detectable flaw size in nondestructive evaluation (NDE). MIL-HDBK-1823 and associated mh1823 POD software gives most common methods of POD analysis. In this paper, POD analysis is applied to an NDE method, such as eddy current testing, where calibration is used. NDE calibration standards have known size artificial flaws such as electro-discharge machined (EDM) notches and flat bottom hole (FBH) reflectors which are used to set instrument sensitivity for detection of real flaws. Real flaws such as cracks and crack-like flaws are desired to be detected using these NDE methods. A reliably detectable crack size is required for safe life analysis of fracture critical parts. Therefore, it is important to correlate signal responses from real flaws with signal responses form artificial flaws used in calibration process to determine reliably detectable flaw size.

  13. System and Method for Multi-Wavelength Optical Signal Detection

    Science.gov (United States)

    McGlone, Thomas D. (Inventor)

    2017-01-01

    The system and method for multi-wavelength optical signal detection enables the detection of optical signal levels significantly below those processed at the discrete circuit level by the use of mixed-signal processing methods implemented with integrated circuit technologies. The present invention is configured to detect and process small signals, which enables the reduction of the optical power required to stimulate detection networks, and lowers the required laser power to make specific measurements. The present invention provides an adaptation of active pixel networks combined with mixed-signal processing methods to provide an integer representation of the received signal as an output. The present invention also provides multi-wavelength laser detection circuits for use in various systems, such as a differential absorption light detection and ranging system.

  14. Power allocation and mode selection methods for cooperative communication in the rectangular tunnel

    Institute of Scientific and Technical Information of China (English)

    Zhai Wenyan; Sun Yanjing; Xu Zhao; Li Song

    2015-01-01

    For the multipath fading on electromagnetic waves of wireless communication in the confined areas, the rectangular tunnel cooperative communication system was established based on the multimode channel model and the channel capacity formula derivation was obtained. On the optimal criterion of the channel capacity, the power allocation methods of both amplifying and forwarding (AF) and decoding and forwarding (DF) cooperative communication systems were proposed in the limitation of the total power to maximize the channel capacity. The mode selection methods of single input single output (SISO) and single input multiple output (SIMO) models in the rectangular tunnel, through which the higher channel capacity can be obtained, were put forward as well. The theoretical analysis and simulation comparison show that, channel capacity of the wireless communication system in the rectangular tunnel can be effectively enhanced through the cooperative technology; channel capacity of the rectangular tunnel under complicated conditions is maximized through the proposed power allocation methods, and the optimal cooperative mode of the channel capacity can be chosen according to the cooperative mode selection methods given in the paper.

  15. [Methods for detection of methylated cytosine residues in DNA].

    Science.gov (United States)

    Smirnikhina, S A; Lavrov, A V

    2009-01-01

    The article provides analysis of common methods for DNA methylation detection. Advantages and limitations of methods used for different purposes are compared. Clue step for most common methods is bisulfite treatment of DNA samples and its protocol is described in details. Recommendations are formulated for each method best in solving specific problems.

  16. METHOD FOR DETECTING AND REPAIRING CYCLE SLIPS IN GPS NAVIGATION

    Institute of Scientific and Technical Information of China (English)

    CHAIYan-ju; OUJi-kun; RENChao

    2005-01-01

    A new method is proposed for detecting and repairing cycle slips in GPS navigation based on the dual frequency observations. It can be implemented through the following three steps: (1) The integer ambiguities of the current epoch are substituted by that of the previous epoch, so the ambiguity parameters are removed from the observation equations. (2) The abnormal observations are detected using the quasi accurate detection (QUAD) method and the satellite pairs of these abnormal observations are determined. Then the coefficient matrix of these satellite pairs is recovered. (3) The cycle slips of these satellite pairs are calculated using the LAMBDA method and integer ambiguities of the current epoch can be determined by adding the cycle slips into the integer ambiguities of the previous epoch. The key of this method is that the abnormal observations must accurately he detected, i.e. , the satellites having cycle slips must correctly be judged. Finally, compared with other methods the feasibility of the method is verified.

  17. Advances in rapid detection methods for foodborne pathogens.

    Science.gov (United States)

    Zhao, Xihong; Lin, Chii-Wann; Wang, Jun; Oh, Deog Hwan

    2014-03-28

    Food safety is increasingly becoming an important public health issue, as foodborne diseases present a widespread and growing public health problem in both developed and developing countries. The rapid and precise monitoring and detection of foodborne pathogens are some of the most effective ways to control and prevent human foodborne infections. Traditional microbiological detection and identification methods for foodborne pathogens are well known to be time consuming and laborious as they are increasingly being perceived as insufficient to meet the demands of rapid food testing. Recently, various kinds of rapid detection, identification, and monitoring methods have been developed for foodborne pathogens, including nucleic-acid-based methods, immunological methods, and biosensor-based methods, etc. This article reviews the principles, characteristics, and applications of recent rapid detection methods for foodborne pathogens.

  18. A Method of Image Symmetry Detection Based on Phase Information

    Institute of Scientific and Technical Information of China (English)

    WU Jun; YANG Zhaoxuan; FENG Dengchao

    2005-01-01

    Traditional methods for detecting symmetry in image suffer greatly from the contrast of image and noise, and they all require some preprocessing. This paper presents a new method of image symmetry detection. This method detects symmetry with phase information utilizing logGabor wavelets, because phase information is stable and significant, while symmetric points produce patterns easy to be recognised and confirmable in local phase. Phase method does not require any preprocessing, and its result is accurate or invariant to contrast, rotation and illumination conditions. This method can detect mirror symmetry, rotating symmetry and curve symmetry at one time. Results of experiment show that, compared with pivotal element algorithm based on intensity information, phase method is more accurate and robust.

  19. A survey of occlusion detection method for visual object

    Institute of Scientific and Technical Information of China (English)

    张世辉

    2016-01-01

    Occlusion problem is one of the challenging issues in vision field for a long time , and the occlu-sion phenomenon of visual object will be involved in many vision research fields .Once the occlusion occurs in a visual system , it will affect the effects of object recognition , tracking, observation and operation , so detecting occlusion autonomously should be one of the abilities for an intelligent vision system .The research on occlusion detection method for visual object has increasingly attracted atten-tions of scholars .First, the definition and classification of the occlusion problem are presented . Then, the characteristics and deficiencies of the occlusion detection methods based on the intensity image and the depth image are analyzed respectively , and the existing occlusion detection methods are compared.Finally, the problems of existing occlusion detection methods and possible research directions are pointed out .

  20. An Improved GLRT Method for Target Detection in SAR Imagery

    Directory of Open Access Journals (Sweden)

    Ju Yingyun

    2015-01-01

    Full Text Available Automatic ground vehicle detection based on SAR imagery is one of the important military applications of SAR. A region-based generalized likelihood ratio test (GLRT method is proposed in this paper, and this method combines the GLRT detection theory and image segmentation technology. First, the SAR imagery is roughly segmented as land clutter region and potential target region through the split and merge procedure often used for processing the original images. Then, based on the segmentation results, the reasonable statistical models for the data in the two regions are built respectively. Finally, with the knowledge of statistical characteristics of clutter and target, GLRT detection method is applied to the each pixel in the potential target region to obtain more accurate detection results. Experimental results based on real SAR data show that the proposed method can effectively detect the ground vehicle targets from the land clutter with excellent accuracy and speed.

  1. Tourism forecasting using modified empirical mode decomposition and group method of data handling

    Science.gov (United States)

    Yahya, N. A.; Samsudin, R.; Shabri, A.

    2017-09-01

    In this study, a hybrid model using modified Empirical Mode Decomposition (EMD) and Group Method of Data Handling (GMDH) model is proposed for tourism forecasting. This approach reconstructs intrinsic mode functions (IMFs) produced by EMD using trial and error method. The new component and the remaining IMFs is then predicted respectively using GMDH model. Finally, the forecasted results for each component are aggregated to construct an ensemble forecast. The data used in this experiment are monthly time series data of tourist arrivals from China, Thailand and India to Malaysia from year 2000 to 2016. The performance of the model is evaluated using Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) where conventional GMDH model and EMD-GMDH model are used as benchmark models. Empirical results proved that the proposed model performed better forecasts than the benchmarked models.

  2. Engine gearbox fault diagnosis using empirical mode decomposition method and Naıve Bayes algorithm

    Indian Academy of Sciences (India)

    KIRAN VERNEKAR; HEMANTHA KUMAR; K V GANGADHARAN

    2017-07-01

    This paper presents engine gearbox fault diagnosis based on empirical mode decomposition (EMD) and Naı¨ve Bayes algorithm. In this study, vibration signals from a gear box are acquired with healthy and different simulated faulty conditions of gear and bearing. The vibration signals are decomposed into a finite number of intrinsic mode functions using the EMD method. Decision tree technique (J48 algorithm) is used for important feature selection out of extracted features. Naı¨ve Bayes algorithm is applied as a fault classifier to know the status of an engine. The experimental result (classification accuracy 98.88%) demonstrates that the proposed approach is an effective method for engine fault diagnosis.

  3. Comparison of methods for detection of norovirus in oysters

    DEFF Research Database (Denmark)

    Schultz, Anna Charlotte; Saadbye, Peter; Hoorfar, Jeffrey

    2007-01-01

    In the absence of culture methods for noroviruses, detection in foods relies on molecular techniques such as Reverse Transcription-Polymerase Chain Reaction (RT-PCR) on extracted viral RNA followed by PCR product confirmation by hybridisation and/or sequencing. However, in order to obtain......V was detected by a single round RT-PCR approach using the primers JV13i and JV12y. The second most efficient method was a method using chloroform extraction and polyethylene precipitation....

  4. Application of Ground Penitrating Radar Method in Pipe Laying Detection

    Institute of Scientific and Technical Information of China (English)

    史付生; 赵学军; 宁书年; 宋喜林; 何亚伟

    2003-01-01

    Ground Penetrating Radar method was used in detecting the flaws of underground pipeline. The GPR layer disturbing image was summarized by using a rational method in fieldwork and the in-door interpretation of data. The mark radar images of disturbance of slight, middle, and strong were obtained. The result shows that the radar method can not only determine the position of the concrete pipeline underground, but it can detect the laying quality of pipeline as well.

  5. Gravitational waves: Classification, Methods of detection, Sensitivities, and Sources

    CERN Document Server

    Kuroda, Kazuaki; Pan, Wei-Ping

    2015-01-01

    After giving a brief introduction and presenting a complete classification of gravitational waves (GWs) according to their frequencies, we review and summarize the detection methods, the sensitivities, and the sources. We notice that real-time detections are possible above 300 pHz. Below 300 pHz, the detections are possible on GW imprints or indirectly. We are on the verge of detection. The progress in this field will be promising and thriving. We will see improvement of a few orders to several orders of magnitude in the GW detection sensitivities over all frequency bands in the next hundred years.

  6. A novel multi-object detection method in HSV space

    Science.gov (United States)

    Tang, Mingfeng; Li, Hongsong; Wen, Yane; Tang, Liping

    2013-07-01

    In order to solve the adverse effects of strong light and shadow on the test results, a fusion frame difference and background subtraction method in the HSV space is used in this paper. By using frame difference method to solve the effect of strong light, but frame difference method can not detect object when the object do not move, the method of background subtraction can detect it, building Gaussian background model in the HSV space can eliminate shadows. Empirical results show that the method of fusion frame difference and background subtraction in the HSV space can get overcome the effect of strong light and shadows. Fusion background subtraction and frame difference method based on establishing a Gaussian mixture model in HSV space can overcome the disadvantages of the frame difference method, at the same time it can also solve the false detection of object which result from the background subtraction method.

  7. Component mode synthesis and large deflection vibration of complex structures. Volume 3: Multiple-mode nonlinear free and forced vibrations of beams using finite element method

    Science.gov (United States)

    Mei, Chuh; Shen, Mo-How

    1987-01-01

    Multiple-mode nonlinear forced vibration of a beam was analyzed by the finite element method. Inplane (longitudinal) displacement and inertia (IDI) are considered in the formulation. By combining the finite element method and nonlinear theory, more realistic models of structural response are obtained more easily and faster.

  8. Generalized Design Method for Voltage-Controlled Current-Mode Multifunction Filters

    Directory of Open Access Journals (Sweden)

    I. Lattenberg

    2009-11-01

    Full Text Available In the article, the Generalized Current Follower Transconductance Amplifier (GCFTA element for generalized frequency filter design and a novel active element, the Programmable Current Amplifier (PCA for the realization of the current-mode analog blocks, are presented. The paper also presents a method of general frequency filter design, whereas the basic circuit is a general autonomous circuit using GCFTA, PCA elements and general admittances. The properties of the proposed filter have been verified using PSPICE simulations.

  9. A method of gear defect intelligent detection based on transmission noise

    Science.gov (United States)

    Chen, Hong-fang; Zhao, Yun; Lin, Jia-chun; Guo, Mian

    2015-02-01

    A new approach was proposed by combing Ensemble Empirical Mode Decomposition (EEMD) algorithm and Back Propagation (BP) neural network for detection of gear through transmission noise analysis. Then feature values of the feature signals are calculated. The feature values which have a great difference for different defect types are chosen to build an eigenvector. BP neural network is used to train and learn on the eigenvector for recognition of gear defects intelligently. In this study, a comparative experiment has been performed among normal gears, cracked gears and eccentric gears with fifteen sets of different gears. Experimental results indicate that the proposed method can detect gear defect features carried by the transmission noise effectively.

  10. A new multivariate empirical mode decomposition method for improving the performance of SSVEP-based brain-computer interface

    Science.gov (United States)

    Chen, Yi-Feng; Atal, Kiran; Xie, Sheng-Quan; Liu, Quan

    2017-08-01

    Objective. Accurate and efficient detection of steady-state visual evoked potentials (SSVEP) in electroencephalogram (EEG) is essential for the related brain-computer interface (BCI) applications. Approach. Although the canonical correlation analysis (CCA) has been applied extensively and successfully to SSVEP recognition, the spontaneous EEG activities and artifacts that often occur during data recording can deteriorate the recognition performance. Therefore, it is meaningful to extract a few frequency sub-bands of interest to avoid or reduce the influence of unrelated brain activity and artifacts. This paper presents an improved method to detect the frequency component associated with SSVEP using multivariate empirical mode decomposition (MEMD) and CCA (MEMD-CCA). EEG signals from nine healthy volunteers were recorded to evaluate the performance of the proposed method for SSVEP recognition. Main results. We compared our method with CCA and temporally local multivariate synchronization index (TMSI). The results suggest that the MEMD-CCA achieved significantly higher accuracy in contrast to standard CCA and TMSI. It gave the improvements of 1.34%, 3.11%, 3.33%, 10.45%, 15.78%, 18.45%, 15.00% and 14.22% on average over CCA at time windows from 0.5 s to 5 s and 0.55%, 1.56%, 7.78%, 14.67%, 13.67%, 7.33% and 7.78% over TMSI from 0.75 s to 5 s. The method outperformed the filter-based decomposition (FB), empirical mode decomposition (EMD) and wavelet decomposition (WT) based CCA for SSVEP recognition. Significance. The results demonstrate the ability of our proposed MEMD-CCA to improve the performance of SSVEP-based BCI.

  11. 25 Years of Self-organized Criticality: Numerical Detection Methods

    Science.gov (United States)

    McAteer, R. T. James; Aschwanden, Markus J.; Dimitropoulou, Michaila; Georgoulis, Manolis K.; Pruessner, Gunnar; Morales, Laura; Ireland, Jack; Abramenko, Valentyna

    2016-01-01

    The detection and characterization of self-organized criticality (SOC), in both real and simulated data, has undergone many significant revisions over the past 25 years. The explosive advances in the many numerical methods available for detecting, discriminating, and ultimately testing, SOC have played a critical role in developing our understanding of how systems experience and exhibit SOC. In this article, methods of detecting SOC are reviewed; from correlations to complexity to critical quantities. A description of the basic autocorrelation method leads into a detailed analysis of application-oriented methods developed in the last 25 years. In the second half of this manuscript space-based, time-based and spatial-temporal methods are reviewed and the prevalence of power laws in nature is described, with an emphasis on event detection and characterization. The search for numerical methods to clearly and unambiguously detect SOC in data often leads us outside the comfort zone of our own disciplines—the answers to these questions are often obtained by studying the advances made in other fields of study. In addition, numerical detection methods often provide the optimum link between simulations and experiments in scientific research. We seek to explore this boundary where the rubber meets the road, to review this expanding field of research of numerical detection of SOC systems over the past 25 years, and to iterate forwards so as to provide some foresight and guidance into developing breakthroughs in this subject over the next quarter of a century.

  12. Landmine detection method combined with backscattering neutrons and capture {gamma}-rays from hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Yoshiyuki, E-mail: ytaka@rri.kyoto-u.ac.j [Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Misawa, Tsuyoshi; Pyeon, Cheol Ho; Shiroya, Seiji [Research Reactor Institute, Kyoto University, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Yoshikawa, Kiyoshi [Institute of Advanced Energy, Kyoto University, Gokashou, Uji-shi, Kyoto 611-0011 (Japan)

    2011-07-15

    The usefulness of the measurements of the backscattering neutron and 2.22 MeV capture {gamma}-ray from hydrogen in the landmine detection method is described in this paper. When the soil moisture content is increased, the reaction rates of both the neutron scattering reaction and capture reaction are increased. However, the backscattering neutrons are more influenced than the capture {gamma}-rays by the soil moisture before the reaction with the detector. The facts that the backscattering neutron method is useful in the dry soil case and that the capture {gamma}-ray method is effective in well-wet soil case are confirmed by the experiments and the calculations. The landmine detection efficiency is improved in various soil moisture conditions by combining the backscattering neutron method together with the capture {gamma}-ray method. The effectiveness of the pulse mode operation was confirmed numerically.

  13. Landmine detection method combined with backscattering neutrons and capture γ-rays from hydrogen.

    Science.gov (United States)

    Takahashi, Yoshiyuki; Misawa, Tsuyoshi; Pyeon, Cheol Ho; Shiroya, Seiji; Yoshikawa, Kiyoshi

    2011-07-01

    The usefulness of the measurements of the backscattering neutron and 2.22MeV capture γ-ray from hydrogen in the landmine detection method is described in this paper. When the soil moisture content is increased, the reaction rates of both the neutron scattering reaction and capture reaction are increased. However, the backscattering neutrons are more influenced than the capture γ-rays by the soil moisture before the reaction with the detector. The facts that the backscattering neutron method is useful in the dry soil case and that the capture γ-ray method is effective in well-wet soil case are confirmed by the experiments and the calculations. The landmine detection efficiency is improved in various soil moisture conditions by combining the backscattering neutron method together with the capture γ-ray method. The effectiveness of the pulse mode operation was confirmed numerically.

  14. Adaptive Sliding Mode Control Method Based on Nonlinear Integral Sliding Surface for Agricultural Vehicle Steering Control

    Directory of Open Access Journals (Sweden)

    Taochang Li

    2014-01-01

    Full Text Available Automatic steering control is the key factor and essential condition in the realization of the automatic navigation control of agricultural vehicles. In order to get satisfactory steering control performance, an adaptive sliding mode control method based on a nonlinear integral sliding surface is proposed in this paper for agricultural vehicle steering control. First, the vehicle steering system is modeled as a second-order mathematic model; the system uncertainties and unmodeled dynamics as well as the external disturbances are regarded as the equivalent disturbances satisfying a certain boundary. Second, a transient process of the desired system response is constructed in each navigation control period. Based on the transient process, a nonlinear integral sliding surface is designed. Then the corresponding sliding mode control law is proposed to guarantee the fast response characteristics with no overshoot in the closed-loop steering control system. Meanwhile, the switching gain of sliding mode control is adaptively adjusted to alleviate the control input chattering by using the fuzzy control method. Finally, the effectiveness and the superiority of the proposed method are verified by a series of simulation and actual steering control experiments.

  15. A novel method for determining target detection thresholds

    Science.gov (United States)

    Grossman, S.

    2015-05-01

    Target detection is the act of isolating objects of interest from the surrounding clutter, generally using some form of test to include objects in the found class. However, the method of determining the threshold is overlooked relying on manual determination either through empirical observation or guesswork. The question remains: how does an analyst identify the detection threshold that will produce the optimum results? This work proposes the concept of a target detection sweet spot where the missed detection probability curve crosses the false detection curve; this represents the point at which missed detects are traded for false detects in order to effect positive or negative changes in the detection probability. ROC curves are used to characterize detection probabilities and false alarm rates based on empirically derived data. It identifies the relationship between the empirically derived results and the first moment statistic of the histogram of the pixel target value data and then proposes a new method of applying the histogram results in an automated fashion to predict the target detection sweet spot at which to begin automated target detection.

  16. Development of a Probabilistic Component Mode Synthesis Method for the Analysis of Non-Deterministic Substructures

    Science.gov (United States)

    Brown, Andrew M.; Ferri, Aldo A.

    1995-01-01

    Standard methods of structural dynamic analysis assume that the structural characteristics are deterministic. Recognizing that these characteristics are actually statistical in nature, researchers have recently developed a variety of methods that use this information to determine probabilities of a desired response characteristic, such as natural frequency, without using expensive Monte Carlo simulations. One of the problems in these methods is correctly identifying the statistical properties of primitive variables such as geometry, stiffness, and mass. This paper presents a method where the measured dynamic properties of substructures are used instead as the random variables. The residual flexibility method of component mode synthesis is combined with the probabilistic methods to determine the cumulative distribution function of the system eigenvalues. A simple cantilever beam test problem is presented that illustrates the theory.

  17. FAULT DIAGNOSIS APPROACH FOR ROLLER BEARINGS BASED ON EMPIRICAL MODE DECOMPOSITION METHOD AND HILBERT TRANSFORM

    Institute of Scientific and Technical Information of China (English)

    Yu Dejie; Cheng Junsheng; Yang Yu

    2005-01-01

    Based upon empirical mode decomposition (EMD) method and Hilbert spectrum, a method for fault diagnosis of roller bearing is proposed. The orthogonal wavelet bases are used to translate vibration signals of a roller bearing into time-scale representation, then, an envelope signal can be obtained by envelope spectrum analysis of wavelet coefficients of high scales. By applying EMD method and Hilbert transform to the envelope signal, we can get the local Hilbert marginal spectrum from which the faults in a roller bearing can be diagnosed and fault patterns can be identified. Practical vibration signals measured from roller bearings with out-race faults or inner-race faults are analyzed by the proposed method. The results show that the proposed method is superior to the traditional envelope spectrum method in extracting the fault characteristics of roller bearings.

  18. A Review of Methods for Detecting Melamine in Food Samples.

    Science.gov (United States)

    Lu, Yang; Xia, Yinqiang; Liu, Guozhen; Pan, Mingfei; Li, Mengjuan; Lee, Nanju Alice; Wang, Shuo

    2017-01-02

    Melamine is a synthetic chemical used in the manufacture of resins, pigments, and superplasticizers. Human beings can be exposed to melamine through various sources such as migration from related products into foods, pesticide contamination, and illegal addition to foods. Toxicity studies suggest that prolonged consumption of melamine could lead to the formation of kidney stones or even death. Therefore, reliable and accurate detection methods are essential to prevent human exposure to melamine. Sample preparation is of critical importance, since it could directly affect the performance of analytical methods. Some methods for the detection of melamine include instrumental analysis, immunoassays, and sensor methods. In this paper, we have summarized the state-of-the-art methods used for food sample preparation as well as the various detection techniques available for melamine. Combinations of multiple techniques and new materials used in the detection of melamine have also been reviewed. Finally, future perspectives on the applications of microfluidic devices have also been provided.

  19. A Generalized Subspace Least Mean Square Method for High-resolution Accurate Estimation of Power System Oscillation Modes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Peng; Zhou, Ning; Abdollahi, Ali

    2013-09-10

    A Generalized Subspace-Least Mean Square (GSLMS) method is presented for accurate and robust estimation of oscillation modes from exponentially damped power system signals. The method is based on orthogonality of signal and noise eigenvectors of the signal autocorrelation matrix. Performance of the proposed method is evaluated using Monte Carlo simulation and compared with Prony method. Test results show that the GSLMS is highly resilient to noise and significantly dominates Prony method in tracking power system modes under noisy environments.

  20. Advanced analytical method of nereistoxin using mixed-mode cationic exchange solid-phase extraction and GC/MS.

    Science.gov (United States)

    Park, Yujin; Choe, Sanggil; Lee, Heesang; Jo, Jiyeong; Park, Yonghoon; Kim, Eunmi; Pyo, Jaesung; Jung, Jee H

    2015-07-01

    Nereistoxin(NTX) was originated from a marine annelid worm Lumbriconereis heteropoda and its analogue pesticides including cartap, bensultap, thiocyclam and thiobensultap have been commonly used in agriculture, because of their low toxicity and high insecticidal activity. However, NTX has been reported about its inhibitory neuro toxicity in human and animal body, by blocking nicotinic acetylcholine receptor and it cause significant neuromuscular toxicity, resulting in respiratory failure. We developed a new method to determine NTX in biological fluid. The method involves mixed-mode cationic exchange based solid phase extraction and gas chromatography/mass spectrometry for final identification and quantitative analysis. The limit of detection and recovery were substantially better than those of other methods using liquid-liquid extraction or headspace solid phase microextraction. The good recoveries (97±14%) in blood samples were obtained and calibration curves over the range 0.05-20 mg/L have R2 values greater than 0.99. The developed method was applied to a fatal case of cartap intoxication of 74 years old woman who ingested cartap hydrochloride for suicide. Cartap and NTX were detected from postmortem specimens and the cause of the death was ruled to be nereistoxin intoxication. The concentrations of NTX were 2.58 mg/L, 3.36 mg/L and 1479.7 mg/L in heart, femoral blood and stomach liquid content, respectively. The heart blood/femoral blood ratio of NTX was 0.76.

  1. Performance evaluation of fault detection methods for wastewater treatment processes.

    Science.gov (United States)

    Corominas, Lluís; Villez, Kris; Aguado, Daniel; Rieger, Leiv; Rosén, Christian; Vanrolleghem, Peter A

    2011-02-01

    Several methods to detect faults have been developed in various fields, mainly in chemical and process engineering. However, minimal practical guidelines exist for their selection and application. This work presents an index that allows for evaluating monitoring and diagnosis performance of fault detection methods, which takes into account several characteristics, such as false alarms, false acceptance, and undesirable switching from correct detection to non-detection during a fault event. The usefulness of the index to process engineering is demonstrated first by application to a simple example. Then, it is used to compare five univariate fault detection methods (Shewhart, EWMA, and residuals of EWMA) applied to the simulated results of the Benchmark Simulation Model No. 1 long-term (BSM1_LT). The BSM1_LT, provided by the IWA Task Group on Benchmarking of Control Strategies, is a simulation platform that allows for creating sensor and actuator faults and process disturbances in a wastewater treatment plant. The results from the method comparison using BSM1_LT show better performance to detect a sensor measurement shift for adaptive methods (residuals of EWMA) and when monitoring the actuator signals in a control loop (e.g., airflow). Overall, the proposed index is able to screen fault detection methods.

  2. Vertically-coupled Whispering Gallery Mode Resonator Optical Waveguide, and Methods

    Science.gov (United States)

    Matsko, Andrey B. (Inventor); Savchenkov, Anatolly A. (Inventor); Matleki, Lute (Inventor)

    2007-01-01

    A vertically-coupled whispering gallery mode (WGM) resonator optical waveguide, a method of reducing a group velocity of light, and a method of making a waveguide are provided. The vertically-coupled WGM waveguide comprises a cylindrical rod portion having a round cross-section and an outer surface. First and second ring-shaped resonators are formed on the outer surface of the cylindrical rod portion and are spaced from each other along a longitudinal direction of the cylindrical rod. The first and second ringshaped resonators are capable of being coupled to each other by way an evanescent field formed in an interior of the cylindrical rod portion.

  3. 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

  4. Method for the detection of Salmonella enterica serovar Enteritidis

    Science.gov (United States)

    Agron, Peter G.; Andersen, Gary L.; Walker, Richard L.

    2008-10-28

    Described herein is the identification of a novel Salmonella enterica serovar Enteritidis locus that serves as a marker for DNA-based identification of this bacterium. In addition, three primer pairs derived from this locus that may be used in a nucleotide detection method to detect the presence of the bacterium are also disclosed herein.

  5. A leaf detection method using image sequences and leaf movement

    NARCIS (Netherlands)

    Hemming, J.; Henten, van E.J.; Tuijl, van B.A.J.; Bontsema, J.

    2005-01-01

    Besides harvesting the fruits, a very time demanding task is removing old leaves from cucumber and tomato plants grown in greenhouses. To be able to automate this process by a robot, a leaf detection method is required. One possibility for the detection is to exploit the different dynamic behaviour

  6. Robust Location of Optical Fiber Modes via the Argument Principle Method

    CERN Document Server

    Chen, Parry Y

    2016-01-01

    We implement a robust, globally convergent root search method for transcendental equations guaranteed to locate all complex roots within a specified search domain, based on Cauchy's residue theorem. Although several implementations of the argument principle already exist, ours has several advantages: it allows singularities within the search domain and branch points are not fatal to the method. Furthermore, our implementation is simple and is written in MATLAB, fulfilling the need for an easily integrated implementation which can be readily modified to accommodate the many variations of the argument principle method, each of which is suited to a different application. We apply the method to the step index fiber dispersion relation, which has become topical due to the recent proliferation of high index contrast fibers. We also find modes with permittivity as the eigenvalue, catering to recent numerical methods that expand the radiation of sources by eigenmodes.

  7. Nested methylation-specific polymerase chain reaction cancer detection method

    Science.gov (United States)

    Belinsky, Steven A.; Palmisano, William A.

    2007-05-08

    A molecular marker-based method for monitoring and detecting cancer in humans. Aberrant methylation of gene promoters is a marker for cancer risk in humans. A two-stage, or "nested" polymerase chain reaction method is disclosed for detecting methylated DNA sequences at sufficiently high levels of sensitivity to permit cancer screening in biological fluid samples, such as sputum, obtained non-invasively. The method is for detecting the aberrant methylation of the p16 gene, O 6-methylguanine-DNA methyltransferase gene, Death-associated protein kinase gene, RAS-associated family 1 gene, or other gene promoters. The method offers a potentially powerful approach to population-based screening for the detection of lung and other cancers.

  8. [Fast Implementation Method of Protein Spots Detection Based on CUDA].

    Science.gov (United States)

    Xiong, Bangshu; Ye, Yijia; Ou, Qiaofeng; Zhang, Haodong

    2016-02-01

    In order to improve the efficiency of protein spots detection, a fast detection method based on CUDA was proposed. Firstly, the parallel algorithms of the three most time-consuming parts in the protein spots detection algorithm: image preprocessing, coarse protein point detection and overlapping point segmentation were studied. Then, according to single instruction multiple threads executive model of CUDA to adopted data space strategy of separating two-dimensional (2D) images into blocks, various optimizing measures such as shared memory and 2D texture memory are adopted in this study. The results show that the operative efficiency of this method is obviously improved compared to CPU calculation. As the image size increased, this method makes more improvement in efficiency, such as for the image with the size of 2,048 x 2,048, the method of CPU needs 52,641 ms, but the GPU needs only 4,384 ms.

  9. White-Light Whispering Gallery Mode Optical Resonator System and Method

    Science.gov (United States)

    Matsko, Andrey B. (Inventor); Savchenkov, Anatoliy A. (Inventor); Maleki, Lute (Inventor)

    2009-01-01

    An optical resonator system and method that includes a whispering-gallery mode (WGM) optical resonator that is capable of resonating across a broad, continuous swath of frequencies is provided. The optical resonator of the system is shaped to support at least one whispering gallery mode and includes a top surface, a bottom surface, a side wall, and a first curved transition region extending between the side wall and the top surface. The system further includes a coupler having a coupling surface which is arranged to face the transition region of the optical resonator and in the vicinity thereof such that an evanescent field emitted from the coupler is capable of being coupled into the optical resonator through the first curved transition region

  10. Reconstruction method of X-mode ultrashort-pulse reflectometry in LHD

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Y; Uchino, K [Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580 (Japan); Mase, A [Art Science and Technology Center for Cooperative Research, Kyushu University, Kasuga 816-8580 (Japan); Kogi, Y [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Tokuzawa, T; Kawahata, K; Nagayama, Y [National Institute for Fusion Science, Toki 509-5292 (Japan); Hojo, H, E-mail: yokotay5@asem.kyushu-u.ac.j [Plasma Research Center, University of Tsukuba, Tsukuba 305-8577 (Japan)

    2010-05-01

    Reflectometry is considered to be one of the key diagnostics to measure density profiles and density fluctuations of fusion oriented plasmas. When an electromagnetic wave is launched into a plasma, the wave is reflected at the corresponding cutoff layer of the ordinary (O) mode or the extraordinary (X) mode. Reflectometry measures the time of flight (TOF) or group delay of the reflected wave. We have applied ultrashort-pulse reflectometry (USPR) to Large Helical Device (LHD) at National Institute for Fusion Science (NIFS). The highspatial analysis method called signal record analysis (SRA) is utilized to reconstruct the density profiles from the TOF signal. Also, it is noted that the remote control system using super science information network (super-SINET) has been introduced to the present USPR system. This remote system is exclusive, and it seems to be quite effective for collaborating experiment of large devices such as ITER.

  11. Field analysis of TE and TM modes in photonic crystal Bragg fibers by transmission matrix method

    Directory of Open Access Journals (Sweden)

    M Hosseini Farzad

    2010-03-01

    Full Text Available In this article, we considered the field analysis in photonic crystal Bragg fibers. We apply the method of transmission matrix to calculater the dispersion curves, the longitudinal wave number over wave number versus incident wavelength, and the field distributions of TE and TM modes in the Bragg fiber. Our analysis shows that the field of guided modes is confined in the core and can exist only in particular wavelength bands corresponding to the band-gap of the periodic structure of the clad. From another point of view, light confinement is due to Bragg reflection from high-and low-refractive index layers of the clad. Also, the diagram of average angular frequency with respect to average longitudinal wave number is plotted so that the band gap regions of the clad are clearly observed.

  12. A boundary integral method for a dynamic, transient mode I crack problem with viscoelastic cohesive zone

    KAUST Repository

    Leise, Tanya L.

    2009-08-19

    We consider the problem of the dynamic, transient propagation of a semi-infinite, mode I crack in an infinite elastic body with a nonlinear, viscoelastic cohesize zone. Our problem formulation includes boundary conditions that preclude crack face interpenetration, in contrast to the usual mode I boundary conditions that assume all unloaded crack faces are stress-free. The nonlinear viscoelastic cohesive zone behavior is motivated by dynamic fracture in brittle polymers in which crack propagation is preceeded by significant crazing in a thin region surrounding the crack tip. We present a combined analytical/numerical solution method that involves reducing the problem to a Dirichlet-to-Neumann map along the crack face plane, resulting in a differo-integral equation relating the displacement and stress along the crack faces and within the cohesive zone. © 2009 Springer Science+Business Media B.V.

  13. Single-Phase Full-Wave Rectifier as an Effective Example to Teach Normalization, Conduction Modes, and Circuit Analysis Methods

    Directory of Open Access Journals (Sweden)

    Predrag Pejovic

    2013-12-01

    Full Text Available Application of a single phase rectifier as an example in teaching circuit modeling, normalization, operating modes of nonlinear circuits, and circuit analysis methods is proposed.The rectifier supplied from a voltage source by an inductive impedance is analyzed in the discontinuous as well as in the continuous conduction mode. Completely analytical solution for the continuous conduction mode is derived. Appropriate numerical methods are proposed to obtain the circuit waveforms in both of the operating modes, and to compute the performance parameters. Source code of the program that performs such computation is provided.

  14. Low complexity MIMO method based on matrix transformation for few-mode multi-core optical transmission system

    Science.gov (United States)

    Pan, Xiaolong; Liu, Bo; Li, Li; Tian, Qinghua

    2016-07-01

    This paper proposes and demonstrates a low complexity multiple-input multiple-output (MIMO) equalization digital signal processing (DSP) method for the few mode multi-core (FMMC) fiber optical transmission system. The MIMO equalization algorithm offers adaptive equalization taps according to the degree of crosstalk in cores or modes, which eliminates the interference among different modes and cores in space division multiplexing (SDM) transmission system. Compared with traditional MIMO method, the proposed scheme has increased the convergence rate by 4 times and reduced the number of finite impulse response (FIR) filters by 55% when the numbers of mode and core are three.

  15. Large amplitude free vibrations of Timoshenko beams at higher modes using coupled displacement field method

    Science.gov (United States)

    Krishna Bhaskar, K.; Meera Saheb, K.

    2015-12-01

    A simple but accurate continuum solution for the shear flexible beam problem using the energy method involves in assuming suitable single term admissible functions for the lateral displacement and total rotation. This leads to two non-linear temporal differential equations in terms of the lateral displacement and the total rotation and are difficult, if not impossible, to solve to obtain the large amplitude fundamental frequencies of beams as a function of the amplitude and slenderness ratios of the vibrating beam. This situation can be avoided if one uses the concept of coupled displacement field where in the fields for lateral displacement and the total rotation are coupled through the static equilibrium equation. In this paper the lateral displacement field is assumed and the field for the total rotation is evaluated through the coupling equation. This approach leads to only one undetermined coefficient which can easily be used in the principle of conservation of total energy of the vibrating beam at a given time, neglecting damping. Finally, through a number of algebraic manipulations, one gets a nonlinear equation of Duffing type which can be solved using any standard method. To demonstrate the simplicity of the method discussed above the problem of large amplitude free vibrations of a uniform shear flexible hinged beam at higher modes with ends immovable to move axially has been solved. The numerical results obtained from the present formulation are in very good agreement with those obtained through finite element and other continuum methods for the fundamental mode, thus demonstrating the efficacy of the proposed method. Also some interesting observations are made with variation of frequency Vs amplitude at different modes.

  16. New method for nonlinear and nonstationary time series analysis: empirical mode decomposition and Hilbert spectral analysis

    Science.gov (United States)

    Huang, Norden E.

    2000-04-01

    A new method for analyzing nonlinear and nonstationary data has been developed. The key pat of the method is the Empirical Mode Decomposition method with which any complicated data set can be decomposed into a finite and often small number of Intrinsic Mode Functions (IMF). An IMF is define das any function having the same numbers of zero- crossing and extrema, and also having symmetric envelopes defined by the local maxima and minima respectively. The IMF also admits well-behaved Hilbert transform. This decomposition method is adaptive, and therefore, highly efficient. Since the decomposition is based on the local characteristic time scale of het data, it is applicable to nonlinear and nonstationary processes. With the Hilbert transform, the IMF yield instantaneous frequencies as functions of time that give sharp identifications of embedded structures. The final presentation of the result is an energy-frequency-time distribution, designated as the Hilbert Spectrum. Comparisons with Wavelet and window Fourier analysis show the new method offers much better temporal and frequency resolutions.

  17. Detection of harmonic signals from chaotic interference by empirical mode decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.G. [State Key Laboratory of Vibration, Shock and Noise, Shanghai Jiao Tong University, Shanghai 200030 (China)]. E-mail: hgli@sjtu.edu.cn; Meng, G. [State Key Laboratory of Vibration, Shock and Noise, Shanghai Jiao Tong University, Shanghai 200030 (China)]. E-mail: gmeng@sjtu.edu.cn

    2006-11-15

    An empirical mode decomposition (EMD) approach to the harmonic signal extraction from chaotic interference is proposed. Based on the EMD and the concept that any signal is composed of a series of simple intrinsic modes, the chaotic interference signal is decomposed to a series of intrinsic mode functions (IMFs), among which one IMF is the recovered harmonic signal. In this study, harmonic signals are contaminated with a chaotic interference signal which is generated by a Duffing oscillator, and the simulation results show that the harmonic signals can be effectively recovered from the contaminated signals by the EMD approach.

  18. [Progress on detection and analysis method of endocrine disrupting compounds].

    Science.gov (United States)

    Du, Hui-Fang; Yan, Hui-Fang

    2005-07-01

    EDCs are new generation of environmental pollutions which are globally concerned. They may cause adverse effect mainly to the endocrine system and nervous system, etc. To assess the EDCs' hazard to the health exactly, we should know about the distribution and level of EDCs in the environment. In this paper, the technique of pretreatment in different matrices, the method of detection and analysis about EDCs were reviewed, and the future's prospect on the study of detection and analysis method were talked about also.

  19. Recent developments in detection methods for microfabricated analytical devices.

    Science.gov (United States)

    Schwarz, M A; Hauser, P C

    2001-09-01

    Sensitive detection in microfluidic analytical devices is a challenge because of the extremely small detection volumes available. Considerable efforts have been made lately to further address this aspect and to investigate techniques other than fluorescence. Among the newly introduced techniques are the optical methods of chemiluminescence, refraction and thermooptics, as well as the electrochemical methods of amperometry, conductimetry and potentiometry. Developments are also in progress to create miniaturized plasma-emission spectrometers and sensitive detectors for gas-chromatographic separations.

  20. Application of Modal Parameter Estimation Methods for Continuous Wavelet Transform-Based Damage Detection for Beam-Like Structures

    Directory of Open Access Journals (Sweden)

    Zhi Qiu

    2015-02-01

    Full Text Available This paper presents a hybrid damage detection method based on continuous wavelet transform (CWT and modal parameter identification techniques for beam-like structures. First, two kinds of mode shape estimation methods, herein referred to as the quadrature peaks picking (QPP and rational fraction polynomial (RFP methods, are used to identify the first four mode shapes of an intact beam-like structure based on the hammer/accelerometer modal experiment. The results are compared and validated using a numerical simulation with ABAQUS software. In order to determine the damage detection effectiveness between the QPP-based method and the RFP-based method when applying the CWT technique, the first two mode shapes calculated by the QPP and RFP methods are analyzed using CWT. The experiment, performed on different damage scenarios involving beam-like structures, shows that, due to the outstanding advantage of the denoising characteristic of the RFP-based (RFP-CWT technique, the RFP-CWT method gives a clearer indication of the damage location than the conventionally used QPP-based (QPP-CWT method. Finally, an overall evaluation of the damage detection is outlined, as the identification results suggest that the newly proposed RFP-CWT method is accurate and reliable in terms of detection of damage locations on beam-like structures.

  1. Non destructive technique for cracks detection by an eddy current in differential mode for steel frames

    Energy Technology Data Exchange (ETDEWEB)

    Harzalla, S., E-mail: harzallahozil@yahoo.fr; Chabaat, M., E-mail: mchabaat@yahoo.com [Built Environmental Research Laboratory, Civil Engineering Faculty, University of Sciences and Technology Houari Boumediene, B.P. 32 El Alia Bab-Ezzouar, Algiers 16111 (Algeria); Belgacem, F. Bin Muhammad, E-mail: fbmbelgacem@gmail.com [Department of Mathematics, Faculty of Basic Education, PAAET, Al-Aardhia (Kuwait)

    2014-12-10

    In this paper, a nondestructive technique is used as a tool to control cracks and microcracks in materials. A simulation by a numerical approach such as the finite element method is employed to detect cracks and eventually; to study their propagation using a crucial parameter such as the stress intensity factor. This approach has been used in the aircraft industry to control cracks. Besides, it makes it possible to highlight the defects of parts while preserving the integrity of the controlled products. On the other side, it is proven that the reliability of the control of defects gives convincing results for the improvement of the quality and the safety of the material. Eddy current testing (ECT) is a standard technique in industry for the detection of surface breaking flaws in magnetic materials such as steels. In this context, simulation tools can be used to improve the understanding of experimental signals, optimize the design of sensors or evaluate the performance of ECT procedures. CEA-LIST has developed for many years semi-analytical models embedded into the simulation platform CIVA dedicated to non-destructive testing. The developments presented herein address the case of flaws located inside a planar and magnetic medium. Simulation results are obtained through the application of the Volume Integral Method (VIM). When considering the ECT of a single flaw, a system of two differential equations is derived from Maxwell equations. The numerical resolution of the system is carried out using the classical Galerkin variant of the Method of Moments. Besides, a probe response is calculated by application of the Lorentz reciprocity theorem. Finally, the approach itself as well as comparisons between simulation results and measured data are presented.

  2. Dynamic baseline detection method for power data network service

    Science.gov (United States)

    Chen, Wei

    2017-08-01

    This paper proposes a dynamic baseline Traffic detection Method which is based on the historical traffic data for the Power data network. The method uses Cisco's NetFlow acquisition tool to collect the original historical traffic data from network element at fixed intervals. This method uses three dimensions information including the communication port, time, traffic (number of bytes or number of packets) t. By filtering, removing the deviation value, calculating the dynamic baseline value, comparing the actual value with the baseline value, the method can detect whether the current network traffic is abnormal.

  3. A method for detecting miners based on helmets detection in underground coal mine videos

    Institute of Scientific and Technical Information of China (English)

    Cai Limei; Qian Jiansheng

    2011-01-01

    In order to monitor dangerous areas in coal mines automatically,we propose to detect helmets from underground coal mine videos for detecting miners.This method can overcome the impact of similarity between the targets and their background.We constructed standard images of helmets,extracted four directional features,modeled the distribution of these features using a Gaussian function and separated local images of frames into helmet and non-helmet classes.Out experimental results show that this method can detect helmets effectively.The detection rate was 83.7%.

  4. Automatic landslide and mudflow detection method via multichannel sparse representation

    Science.gov (United States)

    Chao, Chen; Zhou, Jianjun; Hao, Zhuo; Sun, Bo; He, Jun; Ge, Fengxiang

    2015-10-01

    Landslide and mudflow detection is an important application of aerial images and high resolution remote sensing images, which is crucial for national security and disaster relief. Since the high resolution images are often large in size, it's necessary to develop an efficient algorithm for landslide and mudflow detection. Based on the theory of sparse representation and, we propose a novel automatic landslide and mudflow detection method in this paper, which combines multi-channel sparse representation and eight neighbor judgment methods. The whole process of the detection is totally automatic. We make the experiment on a high resolution image of ZhouQu district of Gansu province in China on August, 2010 and get a promising result which proved the effective of using sparse representation on landslide and mudflow detection.

  5. Efficient Eye Blink Detection Method for disabled-helping domain

    Directory of Open Access Journals (Sweden)

    Assit. Prof. Aree A. Mohammed

    2014-06-01

    Full Text Available In this paper, we present a real time method based on some video and image processing algorithms for eye blink detection. The motivation of this research is the need of disabling who cannot control the calls with human mobile interaction directly without the need of hands. A Haar Cascade Classifier is applied for face and eye detection for getting eye and facial axis information. In addition, the same classifier is used based on Haar- like features to find out the relationship between the eyes and the facial axis for positioning the eyes. An efficient eye tracking method is proposed which uses the position of detected face. Finally, an eye blinking detection based on eyelids state (close or open is used for controlling android mobile phones. The method is used with and without smoothing filter to show the improvement of detection accuracy. The application is used in real time for studying the effect of light and distance between the eyes and the mobile device in order to evaluate the accuracy detection and overall accuracy of the system. Test results show that our proposed method provides a 98% overall accuracy and 100% detection accuracy for a distance of 35 cm and an artificial light.

  6. Numerical Method for Analysis of Waveguide Modes in Planar Gradient Waveguides

    Directory of Open Access Journals (Sweden)

    Volodymyr Mykhailovych FITIO

    2014-09-01

    Full Text Available This paper presents a numerical method developed to find propagation constants of planar waveguide localized modes. The method is based on both the Fourier transform application and the wave equation solution in a frequency domain. As a result, integral equation is obtained where integral is replaced by sum. Finally, a task to find propagation constants and field Fourier transforms in a discrete form is led to the eigenvalue/eigenvector problem. This method provides high accuracy subject to the conditions of the Whittaker-Shannon sampling theorem, and it is characterized by high numerical stability. The method is tested on many examples. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4841

  7. A Finite Element Method for Computation of Structural Intensity by the Normal Mode Approach

    Science.gov (United States)

    Gavrić, L.; Pavić, G.

    1993-06-01

    A method for numerical computation of structural intensity in thin-walled structures is presented. The method is based on structural finite elements (beam, plate and shell type) enabling computation of real eigenvalues and eigenvectors of the undamped structure which then serve in evaluation of complex response. The distributed structural damping is taken into account by using the modal damping concept, while any localized damping is treated as an external loading, determined by use of impedance matching conditions and eigenproperties of the structure. Emphasis is given to aspects of accuracy of the results and efficiency of the numerical procedures used. High requirements on accuracy of the structural response (displacements and stresses) needed in intensity applications are satisfied by employing the "swept static solution", which effectively takes into account the influence of higher modes otherwise inaccessible to numerical computation. A comparison is made between the results obtained by using analytical methods and the proposed numerical procedure to demonstrate the validity of the method presented.

  8. Integration of high resolution geophysical methods. Detection of shallow depth bodies of archaeological interest

    Directory of Open Access Journals (Sweden)

    F. Rosso

    1998-06-01

    Full Text Available A combined survey using ground penetrating radar, self-potential, geoelectrical and magnetic methods has been carried out to detect near-surface tombs in the archaeological test site of the Sabine Necropolis at Colle del Forno, Rome, Italy. A 2D data acquisition mode has been adopted to obtain a 3D image of the investigated volumes. The multi-methodological approach has not only demonstrated the reliability of each method in delineating the spatial behaviour of the governing parameter, but mainly helped to obtain a detailed physical image closely conforming to the target geometry through the whole set of parameters involved.

  9. Nonlinear viscous damping and gravitational wave detectability of the f-mode instability in neutron stars

    CERN Document Server

    Passamonti, A

    2011-01-01

    We study the damping of the gravitational radiation-driven f-mode instability in ro- tating neutron stars by nonlinear bulk viscosity in the so-called supra-thermal regime. In this regime the dissipative action of bulk viscosity is known to be enhanced as a result of nonlinear contributions with respect to the oscillation amplitude. Our anal- ysis of the f-mode instability is based on a time-domain code that evolves linear perturbations of rapidly rotating polytropic neutron star models. The extracted mode frequency and eigenfunctions are subsequently used in standard energy integrals for the gravitational wave growth and viscous damping. We find that nonlinear bulk vis- cosity has a moderate impact on the size of the f-mode instability window, becoming an important factor and saturating the mode's growth at a relatively large oscillation amplitude. We show that a similar result holds for the damping of the inertial r-mode instability by nonlinear bulk viscosity. In addition, we show that the action of bulk v...

  10. NETWORK INTRUSION DETECTION METHOD BASED ON RS-MSVM

    Institute of Scientific and Technical Information of China (English)

    Xiao Yun; Han Chongzhao; Zheng Qinghua; Zhang Junjie

    2006-01-01

    A new method called RS-MSVM (Rough Set and Multi-class Support Vector Machine) is proposed for network intrusion detection. This method is based on rough set followed by MSVM for attribute reduction and classification respectively. The number of attributes of the network data used in this paper is reduced from 41 to 30 using rough set theory. The kernel function of HVDM-RBF (Heterogeneous Value Difference Metric Radial Basis Function), based on the heterogeneous value difference metric of heterogeneous datasets, is constructed for the heterogeneous network data. HVDM-RBF and one-against-one method are applied to build MSVM. DARPA (Defense Advanced Research Projects Agency) intrusion detection evaluating data were used in the experiment. The testing results show that our method outperforms other methods mentioned in this paper on six aspects: detection accuracy, number of support vectors, false positive rate, false negative rate, training time and testing time.

  11. A Study on the Power Generation Capacity of Piezoelectric Energy Harvesters with Different Fixation Modes and Adjustment Methods

    OpenAIRE

    Zhixiang Li; Gongbo Zhou; Zhencai Zhu; Wei Li

    2016-01-01

    The power generation capacity of piezoelectric energy harvesters (PEHs) is not only related to the properties of the piezoelectric material, the vibration magnitude and the subsequent conditioning circuit, but also to the fixation modes and adjustment methods. In this paper, a commercial piezoelectric ceramic plate (PCP) in simply supported beam fixation mode and cantilever beam fixation mode were analyzed through finite element simulations and experiments, and furthermore, two ways of adjust...

  12. A Prognostic Method for Fault Detection in Wind Turbine Drivetrains

    DEFF Research Database (Denmark)

    Nejada, Amir R.; Odgaard, Peter Fogh; Gao, Zhen

    2014-01-01

    In this paper, a prognostic method is presented for fault detection in gears and bearings in wind turbine drivetrains. This method is based on angular velocity measurements from the gearbox input shaft and the output to the generator, using two additional angular velocity sensors on the intermedi......In this paper, a prognostic method is presented for fault detection in gears and bearings in wind turbine drivetrains. This method is based on angular velocity measurements from the gearbox input shaft and the output to the generator, using two additional angular velocity sensors...... on the intermediate shafts inside the gearbox. An angular velocity error function is defined and compared in the faulty and fault-free conditions in frequency domain. Faults can be detected from the change in the energy level of the frequency spectrum of an error function. The method is demonstrated by detecting...... a dynamometer test bench and applied to the numerical gearbox model. The method is exemplified using a 750 kW wind turbine gearbox. The case study results show that defects in the high- and intermediate-speed bearings can be detected using this method. It is shown that this procedure is relatively simple, yet...

  13. Export Methods in Fault Detection and Localization Mechanisms

    Directory of Open Access Journals (Sweden)

    Aymen Belghith

    2012-07-01

    Full Text Available Monitoring the quality of service in a multi-domain network allows providers to ensure the control of multi-domain service performance. A multi-domain service is a service that crosses multiple domains. In this paper, we propose several mechanisms for fault detection and fault localization. A fault is detected when an end-to-end contract is not respected. Faulty domains are domains that do not fulfill their Quality of Service (QoS requirements. Our three proposed fault detection and localization mechanisms (FDLM depend on the export method used. These export methods define how the measurement results are exported for analysis. We consider the periodic export, the triggered export, and a combined method. For each FDLM, we propose two sub-schemes that use different fault detection strategies. In this paper, we describe these mechanisms and evaluate their performance using Network Simulator (NS-2.

  14. Support system and method for detecting neurodegenerative disorder

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a system and a method for detection of abnormal motor activity during REM sleep, and further to systems and method for assisting in detecting neurodegenerative disorders such as Parkinson's. One embodiment relates to a method for detection of abnormal motor activity...... during REM sleep comprising the steps of: performing polysomnographic recordings of a sleeping subject, thereby obtaining one or more electromyography (EMG) derivations, preferably surface EMG recordings, and one or more EEG derivations, and/or one or more electrooculargraphy (EOG) derivations, detecting...... one or more REM sleep stages, preferably based on the one or more EEG and/or EOG derivations, determining the level of muscle activity during the one or more REM sleep stages based on the one or more EMG derivations, wherein a subject having an increased level of muscle activity during REM sleep...

  15. Musical Tone Law Method for the Structural Damage Detection

    Directory of Open Access Journals (Sweden)

    Weisong Yang

    2017-01-01

    Full Text Available Damage detection tests of inclined cables, steel pipes, spherical shells, and an actual cable-stayed bridge were conducted based on the proposed musical tone law method. The results show that the musical tone law method could be used in the damage detection of isotropic material structures with simple shape, like cables, pipes, plates, and shells. Having distinct spectral lines like a comb with a certain interval distribution rule is the main characteristic of the music tone law. Damage detection baseline could be established by quantizing the fitting relationship between modal orders and the corresponding frequency values. The main advantage of this method is that it could be used in the structural damage detection without vibration information of an intact structure as a reference.

  16. Detection of B-mode Polarization in the Cosmic Microwave Background with Data from the South Pole Telescope

    CERN Document Server

    Hanson, D; Crites, A; Ade, P A R; Aird, K A; Austermann, J E; Beall, J A; Bender, A N; Benson, B A; Bleem, L E; Bock, J J; Carlstrom, J E; Chang, C L; Chiang, H C; Cho, H-M; Conley, A; Crawford, T M; de Haan, T; Dobbs, M A; Everett, W; Gallicchio, J; Gao, J; George, E M; Halverson, N W; Harrington, N; Henning, J W; Hilton, G C; Holder, G P; Holzapfel, W L; Hrubes, J D; Huang, N; Hubmayr, J; Irwin, K D; Keisler, R; Knox, L; Lee, A T; Leitch, E; Li, D; Liang, C; Luong-Van, D; Marsden, G; McMahon, J J; Mehl, J; Meyer, S S; Mocanu, L; Montroy, T E; Natoli, T; Nibarger, J P; Novosad, V; Padin, S; Pryke, C; Reichardt, C L; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Schulz, B; Smecher, G; Stark, A A; Story, K; Tucker, C; Vanderlinde, K; Vieira, J D; Viero, M P; Wang, G; Yefremenko, V; Zahn, O; Zemcov, M

    2013-01-01

    Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a non-zero correlation at 7.7 sigma significance. The correlation has an amplitude and scale-dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmo...

  17. Method for predicting whispering gallery mode spectra of active spherical microresonators

    CERN Document Server

    Hall, Jonathan M M; Henderson, Matthew R; Francois, Alexandre; Reynolds, Tess; Riesen, Nicolas; Monro, Tanya M

    2014-01-01

    A full three-dimensional Finite-Difference Time-Domain (FDTD)-based toolkit is developed to simulate the whispering gallery modes of a microsphere in the vicinity of a dipole source, placed on the surface. This provides a guide for experiments that rely on coupling to active microspheres. The resultant spectra are compared to those of analytic models used in the field. In contrast to the analytic models, the FDTD method is able to collect flux from an arbitrary collection region, such as a disk-shaped region, analogous to an optical fibre. The flux collection time may also be altered to access transient phenomena that may not appear at long collection times. The customisability of the technique allows one to consider a variety of mode excitation scenarios, such as refractive index inhomogeneity in the material, and different resonator shapes, such as shells and ellipsoids. The coupling efficiency to specific modes within wavelength regions can thus be optimized, preselecting the desired optical properties pri...

  18. Detection of gravity modes in the massive binary V380 Cyg from Kepler spacebased photometry and high-resolution spectroscopy

    CERN Document Server

    Tkachenko, A; Pavlovski, K; Southworth, J; Degroote, P; Debosscher, J; Still, M; Bryson, S; Molenberghs, G; Bloemen, S; de Vries, B L; Hrudkova, M; Lombaert, R; Neyskens, P; Papics, P I; Raskin, G; Van Winckel, H; Morris, R L; Sanderfer, D T; Seader, S E

    2012-01-01

    We report the discovery of low-amplitude gravity-mode oscillations in the massive binary star V380 Cyg, from 180 d of Kepler custom-aperture space photometry and 5 months of high-resolution high signal-to-noise spectroscopy. The new data are of unprecedented quality and allowed to improve the orbital and fundamental parameters for this binary. The orbital solution was subtracted from the photometric data and led to the detection of periodic intrinsic variability with frequencies of which some are multiples of the orbital frequency and others are not. Spectral disentangling allowed the detection of line-profile variability in the primary. With our discovery of intrinsic variability interpreted as gravity mode oscillations, V380 Cyg becomes an important laboratory for future seismic tuning of the near-core physics in massive B-type stars.

  19. Detecting Free-Mass Common-Mode Motion Induced by Incident Gravitational Waves: Testing General Relativity and Source Direction via Fox-Smith and Michelson Interferometers

    CERN Document Server

    Tobar, Michael Edmund; Kuroda, Kazuaki

    2009-01-01

    In this paper we show that information on both the differential and common mode free-mass response to a gravitational wave can provide important information on discriminating the direction of the gravitational wave source and between different theories of gravitation. The conventional Michelson interferometer scheme only measures the differential free-mass response. By changing the orientation of the beam splitter, it is possible to configure the detector so it is sensitive to the common-mode of the free-mass motion. The proposed interferometer is an adaptation of the Fox-Smith interferometer. A major limitation to the new scheme is its enhanced sensitivity to laser frequency fluctuations over the conventional, and we propose a method of canceling these fluctuations. The configuration could be used in parallel to the conventional differential detection scheme with a significant sensitivity and bandwidth.

  20. A method for detecting positive growth autocorrelation without marking individuals.

    Directory of Open Access Journals (Sweden)

    Mollie E Brooks

    Full Text Available In most ecological studies, within-group variation is a nuisance that obscures patterns of interest and reduces statistical power. However, patterns of within-group variability often contain information about ecological processes. In particular, such patterns can be used to detect positive growth autocorrelation (consistent variation in growth rates among individuals in a cohort across time, even in samples of unmarked individuals. Previous methods for detecting autocorrelated growth required data from marked individuals. We propose a method that requires only estimates of within-cohort variance through time, using maximum likelihood methods to obtain point estimates and confidence intervals of the correlation parameter. We test our method on simulated data sets and determine the loss in statistical power due to the inability to identify individuals. We show how to accommodate nonlinear growth trajectories and test the effects of size-dependent mortality on our method's accuracy. The method can detect significant growth autocorrelation at moderate levels of autocorrelation with moderate-sized cohorts (for example, statistical power of 80% to detect growth autocorrelation ρ (2 = 0.5 in a cohort of 100 individuals measured on 16 occasions. We present a case study of growth in the red-eyed tree frog. Better quantification of the processes driving size variation will help ecologists improve predictions of population dynamics. This work will help researchers to detect growth autocorrelation in cases where marking is logistically infeasible or causes unacceptable decreases in the fitness of marked individuals.

  1. A swarm intelligence-based tuning method for the Sliding Mode Generalized Predictive Control.

    Science.gov (United States)

    Oliveira, J B; Boaventura-Cunha, J; Moura Oliveira, P B; Freire, H

    2014-09-01

    This work presents an automatic tuning method for the discontinuous component of the Sliding Mode Generalized Predictive Controller (SMGPC) subject to constraints. The strategy employs Particle Swarm Optimization (PSO) to minimize a second aggregated cost function. The continuous component is obtained by the standard procedure, by Quadratic Programming (QP), thus yielding an online dual optimization scheme. Simulations and performance indexes for common process models in industry, such as nonminimum phase and time delayed systems, result in a better performance, improving robustness and tracking accuracy.

  2. Stochastic sandwich method with low mode substitution for nucleon isovector matrix elements

    CERN Document Server

    Yang, Yi-Bo; Draper, Terrence; Gong, Ming; Liu, Keh-Fei

    2015-01-01

    We introduce a stochastic sandwich method with low-mode substitution to evaluate the connected three-point functions. The isovector matrix elements of the nucleon for the axial-vector coupling $g_A^3$, scalar couplings $g_S^3$ and the quark momentum fraction $\\langle x\\rangle_{u -d}$ are calculated with overlap fermion on 2+1 flavor domain-wall configurations on a $24^3 \\times 64$ lattice at $m_{\\pi} = 330$ MeV with lattice spacing $a = 0.114$ fm.

  3. Face/core mixed mode debond fracture toughness characterization using the modified TSD test method

    DEFF Research Database (Denmark)

    Berggreen, Christian; Quispitupa, Amilcar; Costache, Andrei;

    2014-01-01

    The modified tilted sandwich debond (TSD) test method is used to examine face/core debond fracture toughness of sandwich specimens with glass/polyester face sheets and PVC H45 and H100 foam cores over a large range of mode-mixities. The modification was achieved by reinforcing the loaded face sheet....... The fracture process was inspected visually during and after testing. For specimens with H45 core the crack propagated in the core. For specimens with an H100 core, the crack propagated between the resin-rich layer and the face sheet. © The Author(s) 2013 Reprints and permissions: sagepub...

  4. A modified split—step fourier method for optical pulse propagation with polarization mode dispersion

    Institute of Scientific and Technical Information of China (English)

    RaoMin; SunXiao-Han; ZhangMing-De

    2003-01-01

    A modified split-step Fourier method (SSFM) is presented to solve the coupled nonlinear Schroedinger equation (CNLS) that can be used to model high-speed pulse propagation in optical fibres with polarization mode dispersion (PMD). We compare our approach with the SSFM and demonstrate that our approach is much faster with no loss of pre-chirped RZ(CRZ) formats in the presence of high PMD through this approach. The simulation results show that CRZ pulses are the most tolerant to high PMD values and the extinct ratio has a great impact on the transmission performance.

  5. Subpixel edge detection method based on low-frequency filtering

    Science.gov (United States)

    Bylinsky, Yosip Y.; Kotyra, Andrzej; Gromaszek, Konrad; Iskakova, Aigul

    2016-09-01

    A method of edge detection in images is proposed basing that based on low-frequency filtering. The method uses polynomial interpolation to determine the coordinates of the edge point with subpixel accuracy. Some experiments have been results also have been provided.

  6. Method Designed To Detect Alginate-Degrading Bacteria

    OpenAIRE

    Kitamikado, Manabu; Yamaguchi, Kuniko; Tseng, Chao-Huang; Okabe, Bun'Ichi

    1990-01-01

    A simple turbidimetric method was developed to detect alginate degradation. Bacteria were grown in alginate-containing media, and culture fluids were mixed with an acidic albumin solution. Failure to develop a white turbidity indicated an alginate degrader. The method showed alginate degradation by Vibrio alginolyticus ATCC 17749, in contrast to prior descriptions.

  7. Soybean allergen detection methods--a comparison study

    DEFF Research Database (Denmark)

    Pedersen, M. Højgaard; Holzhauser, T.; Bisson, C.

    2008-01-01

    Soybean containing products are widely consumed, thus reliable methods for detection of soy in foods are needed in order to make appropriate risk assessment studies to adequately protect soy allergic patients. Six methods were compared using eight food products with a declared content of soy...

  8. Improved Fractal Method for Singularity Detection in Fingerprint Images

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new technique that uses Discrete Fractal Brownian Motion todescribe a fingerprint is presented. By computing certain fractal parameters, a fingerprints core and delta fields can be roughly detected. Experimental results demonstrate this method to be not only more efficient than the single fractal dimension method, but also more noise-resistant than the traditional schemes.

  9. Extreme-Point Symmetric Mode Decomposition Method for Nonlinear and Non-Stationary Signal Processing

    CERN Document Server

    Wang, Jin-Liang

    2013-01-01

    To process nonlinear and non-stationary signals, an extreme-point symmetric mode decomposition (ESMD) method is developed. It can be seen as a new alternate of the well-known Hilbert-Huang transform (HHT) method which is widely used nowadays. There are two parts for it. The first part is the decomposition approach which yields a series of intrinsic mode functions (IMFs) together with an optimal adaptive global mean (AGM) curve, the second part is the direct interpolating (DI) approach which yields instantaneous amplitudes and frequencies for the IMFs together with a time-varying energy. Relative to the HHT method it has five characteristics as follows: (1) Different from constructing 2 outer envelopes, its sifting process is implemented by the aid of 1, 2 or 3 inner interpolating curves; (2) It does not decompose the signal to the last trend curve with at most one extreme point, it optimizes the residual component to be an optimal AGM curve which possesses a certain number of extreme points; (3) Its symmetry ...

  10. Research on the Equivalence Between Double Differential-mode Current Injection and Radiation Test Method

    Institute of Scientific and Technical Information of China (English)

    PAN Xiaodong; WEI Guanghui; FAN Lisi; LU Xinfu; YANG Zhe

    2013-01-01

    There are the application scope limits for single differential-mode current injection test method,so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cable simultaneously,a double differential-mode current injection test method (DDMCI) is proposed.The method adopted the equivalence source wave theorem and Baum-Liu-Tesche (BLT)equation as its theory foundation.The equivalent corresponding relation between injection voltage and radiation electric field intensity is derived,and the phase relation between the two injection voltage sources is confirrned.The results indicate that the amplitude and phase of the equivalent injection voltage source is closely related to the S parameter of directional coupling device,the transmission line length,and the source vector in BLT equation,but has nothing to do with the reflection coefficient between the two equipment pieces.Therefore,by choosing the right amplitude and phase of the double injection voltage sources,the DDMCI test is equivalent to the radiation test for two interconnected equipment of a system.

  11. Statistical methods for damage detection applied to civil structures

    DEFF Research Database (Denmark)

    Gres, Szymon; Ulriksen, Martin Dalgaard; Döhler, Michael

    2017-01-01

    of the two damage detection methods is similar, hereby implying merit of the new Mahalanobis distance-based approach, as it is less computational complex. The fusion of the damage indicators in the control chart provides the most accurate view on the progressively damaged systems....... and compared to the well-known subspace-based damage detection algorithm in the context of two large case studies. Both methods are implemented in the modal analysis and structural health monitoring software ARTeMIS, in which the joint features of the methods are concluded in a control chart in an attempt...

  12. Methods for detection of GMOs in food and feed.

    Science.gov (United States)

    Marmiroli, Nelson; Maestri, Elena; Gullì, Mariolina; Malcevschi, Alessio; Peano, Clelia; Bordoni, Roberta; De Bellis, Gianluca

    2008-10-01

    This paper reviews aspects relevant to detection and quantification of genetically modified (GM) material within the feed/food chain. The GM crop regulatory framework at the international level is evaluated with reference to traceability and labelling. Current analytical methods for the detection, identification, and quantification of transgenic DNA in food and feed are reviewed. These methods include quantitative real-time PCR, multiplex PCR, and multiplex real-time PCR. Particular attention is paid to methods able to identify multiple GM events in a single reaction and to the development of microdevices and microsensors, though they have not been fully validated for application.

  13. Method of detecting genetic translocations identified with chromosomal abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Joe W. (Livermore, CA); Pinkel, Daniel (Walnut Creek, CA); Tkachuk, Douglas (Livermore, CA)

    2001-01-01

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyses. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acid probes are typically of a complexity greater than 50 kb, the complexity depending upon the cytogenetic application. Methods and reagents are provided for the detection of genetic rearrangements. Probes and test kits are provided for use in detecting genetic rearrangements, particularly for use in tumor cytogenetics, in the detection of disease related loci, specifically cancer, such as chronic myelogenous leukemia (CML) and for biological dosimetry. Methods and reagents are described for cytogenetic research, for the differentiation of cytogenetically similar but genetically different diseases, and for many prognostic and diagnostic applications.

  14. Method of detecting genetic deletions identified with chromosomal abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Joe W; Pinkel, Daniel; Tkachuk, Douglas

    2013-11-26

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyzes. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acids probes are typically of a complexity greater tha 50 kb, the complexity depending upon the cytogenetic application. Methods and reagents are provided for the detection of genetic rearrangements. Probes and test kits are provided for use in detecting genetic rearrangements, particlularly for use in tumor cytogenetics, in the detection of disease related loci, specifically cancer, such as chronic myelogenous leukemia (CML) and for biological dosimetry. Methods and reagents are described for cytogenetic research, for the differentiation of cytogenetically similar ut genetically different diseases, and for many prognostic and diagnostic applications.

  15. Method of detecting genetic deletions identified with chromosomal abnormalities

    Science.gov (United States)

    Gray, Joe W; Pinkel, Daniel; Tkachuk, Douglas

    2013-11-26

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyzes. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acids probes are typically of a complexity greater tha 50 kb, the complexity depending upon the cytogenetic application. Methods and reagents are provided for the detection of genetic rearrangements. Probes and test kits are provided for use in detecting genetic rearrangements, particlularly for use in tumor cytogenetics, in the detection of disease related loci, specifically cancer, such as chronic myelogenous leukemia (CML) and for biological dosimetry. Methods and reagents are described for cytogenetic research, for the differentiation of cytogenetically similar ut genetically different diseases, and for many prognostic and diagnostic applications.

  16. Distance Based Method for Outlier Detection of Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Haibin Zhang

    2016-01-01

    Full Text Available We propose a distance based method for the outlier detection of body sensor networks. Firstly, we use a Kernel Density Estimation (KDE to calculate the probability of the distance to k nearest neighbors for diagnosed data. If the probability is less than a threshold, and the distance of this data to its left and right neighbors is greater than a pre-defined value, the diagnosed data is decided as an outlier. Further, we formalize a sliding window based method to improve the outlier detection performance. Finally, to estimate the KDE by training sensor readings with errors, we introduce a Hidden Markov Model (HMM based method to estimate the most probable ground truth values which have the maximum probability to produce the training data. Simulation results show that the proposed method possesses a good detection accuracy with a low false alarm rate.

  17. Simultaneous determination of isoflavones and resveratrols for adulteration detection of soybean and peanut oils by mixed-mode SPE LC-MS/MS.

    Science.gov (United States)

    Zhao, Xin; Ma, Fei; Li, Peiwu; Li, Guangming; Zhang, Liangxiao; Zhang, Qi; Zhang, Wen; Wang, Xiupin

    2015-06-01

    To ensure authenticity of vegetable oils, isoflavones (genistein, genistin, daidzein and daidzin) and resveratrols (cis-resveratrol and trans-resveratrol) were selected as the putative markers for adulteration of soybean and peanut oils. Firstly, mixed mode solid-phase extraction coupled with liquid chromatography tandem mass spectrometry (mixed-mode SPE LC-MS/MS) method was developed to analyze isoflavones and resveratrols in vegetable oils. The concentration of marker compounds in vegetable oils were 0.08-1.47mgkg(-1) for daidzein, ND-78.9μgkg(-1) for daidzin, 0.40-5.89mgkg(-1) for genistein, 1.2-114.9μgkg(-1) for genistin, 3.1-85.0μgkg(-1) for trans-resveratrol and 1.9-51.0μgkg(-1) for cis-resveratrol, which are compatible with the raw materials for oil press. Additionally, the applicability of this method has been successfully tested in thirteen vegetable oils from the market. Mixed-mode SPE LC-MS/MS method can simultaneously detect isoflavones and resveratrols in vegetable oils and assess adulteration and quality of soybean and peanut oils.

  18. Methods for testing automatic mode switching in patients implanted with DDD(R) pacemakers.

    Science.gov (United States)

    Lau, Chu-Pak; Mascia, Franco; Corbucci, Giorgio; Padeletti, Luigi

    2004-01-01

    The assessment of automatic mode switching (AMS) algorithms is impossible in vivo, due to a low chance of seeing the patient at the onset of a spontaneous episode of atrial fibrillation (AF). As the induction of AF to test AMS has clinical concerns, three alternative and non-invasive techniques may be proposed for this purpose: myopotentials, chest wall stimulation, and an external supraventricular arrhythmia simulator. The first method is simple and does not require additional equipment, even though in some patients adequate signals cannot be generated with a soft effort such as handgrip or hand compression. The main advantage of the chest wall stimulation method is the possibility that it be performed in every implanting center, since it is based on the use of standard devices for cardiac stimulation. The method based on the external supraventricular arrhythmia simulator allows the most detailed of the ECG traces, but it needs a dedicated electronic device.

  19. Dual-mode nested search method for categorical uncertain multi-objective optimization

    Science.gov (United States)

    Tang, Long; Wang, Hu

    2016-10-01

    Categorical multi-objective optimization is an important issue involved in many matching design problems. Non-numerical variables and their uncertainty are the major challenges of such optimizations. Therefore, this article proposes a dual-mode nested search (DMNS) method. In the outer layer, kriging metamodels are established using standard regular simplex mapping (SRSM) from categorical candidates to numerical values. Assisted by the metamodels, a k-cluster-based intelligent sampling strategy is developed to search Pareto frontier points. The inner layer uses an interval number method to model the uncertainty of categorical candidates. To improve the efficiency, a multi-feature convergent optimization via most-promising-area stochastic search (MFCOMPASS) is proposed to determine the bounds of objectives. Finally, typical numerical examples are employed to demonstrate the effectiveness of the proposed DMNS method.

  20. MIRROR EXTENDING AND CIRCULAR SPLINE FUNCTION FOR EMPIRICAL MODE DECOMPOSITION METHOD

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Mirror Extending (ME) approach is proposed in this paper for solving the end extending issue in the Empirical Mode Decomposition (EMD) method. By this approach, the data is extended into a closed circuit without end. The derivatives on ends are not necessary any more for Spline fitting. The approach eliminates the possible problems in reliability and uniqueness in the original extending approach of the EMD method. In the ME approach only one extending is necessary before the data analysis. A theoretical criterion is proposed here for checking the extending approach. ME approach has been proved to satisfy the theoretical criterion automatically and permanently. This approach makes the EMD method reliable and easy to follow.

  1. [Molecular Detection Methods for Vibrio parahaemolyticus in Seafood].

    Science.gov (United States)

    Nishio, Tomohiro; Ohtsuka, Kayoko; Oda, Midori; Sugiyama, Kanji; Hara-Kudo, Yukiko

    2015-07-01

    To detect Vibrio parahaemolyticus in seafood, we evaluated efficient combinations of molecular methods with DNA extraction methods using heat extraction and alkaline heat extraction, and PCR, real-time PCR and loop-mediated isothermal amplification (LAMP) assays were performed targeting V parahaemolyticus species-specific genes (tlh and rpoD) and pathogenic factors genes (tdh and trh). The species-specific genes were detected in all combinations of two strains (a tdh * trh1-positive strain and a trh2-positive strain), two kinds of shellfish (oyster and bloody clams) and molecular methods with tlh-real time PCR or rpoD-LAMP assays with DNA of alkaline heat extraction at 85-145cfu/test level. tdh was detected in both seafoods with real time PCR assay with DNA of heat extraction at 85cfu/test level, and detected with the LAMP and real time PCR assays with DNA of alkaline heat extraction at 85cfu/test level. Detection of both trh1 and trh2 with the PCR assay with DNA of alkaline heat extraction was comparatively high though trh2 was detected with the LAMP assay with DNA of alkaline heat extraction at 145cfu/test level. It, however, is necessary to investigate more sensitive trh-detection methods. In this study, the results indicated that tlh-real time PCR or rpoD-LAMP, tdh-real time PCR and tdh-LAMP assays with DNA of alkaline heat extraction are relatively-sensitive methods to detect V. parahaemolyticus in seafood.

  2. EEMD-based multiscale ICA method for slewing bearing fault detection and diagnosis

    Science.gov (United States)

    Žvokelj, Matej; Zupan, Samo; Prebil, Ivan

    2016-05-01

    A novel multivariate and multiscale statistical process monitoring method is proposed with the aim of detecting incipient failures in large slewing bearings, where subjective influence plays a minor role. The proposed method integrates the strengths of the Independent Component Analysis (ICA) multivariate monitoring approach with the benefits of Ensemble Empirical Mode Decomposition (EEMD), which adaptively decomposes signals into different time scales and can thus cope with multiscale system dynamics. The method, which was named EEMD-based multiscale ICA (EEMD-MSICA), not only enables bearing fault detection but also offers a mechanism of multivariate signal denoising and, in combination with the Envelope Analysis (EA), a diagnostic tool. The multiscale nature of the proposed approach makes the method convenient to cope with data which emanate from bearings in complex real-world rotating machinery and frequently represent the cumulative effect of many underlying phenomena occupying different regions in the time-frequency plane. The efficiency of the proposed method was tested on simulated as well as real vibration and Acoustic Emission (AE) signals obtained through conducting an accelerated run-to-failure lifetime experiment on a purpose-built laboratory slewing bearing test stand. The ability to detect and locate the early-stage rolling-sliding contact fatigue failure of the bearing indicates that AE and vibration signals carry sufficient information on the bearing condition and that the developed EEMD-MSICA method is able to effectively extract it, thereby representing a reliable bearing fault detection and diagnosis strategy.

  3. Novel picture of the soft modes at the QCD critical point based on the FRG method

    CERN Document Server

    Yokota, Takeru; Morita, Kenji

    2016-01-01

    We investigate the soft mode at the QCD critical point (CP) on the basis of the functional renormalization group. We calculate the spectral functions in the meson channels in the two-flavor quark--meson model. Our result shows that the energy of the peak position of the particle--hole mode in the sigma channel becomes vanishingly small as the system approaches the QCD CP, which is a manifestation of the softening of the phonon mode. We also extract the dispersion curves of the mesonic and the phonon mode, a hydrodynamic mode which leads to a finding that the dispersion curve of the sigma-mesonic mode crosses the light-cone into the space-like momentum region, and then eventually merges into the phonon mode as the system approaches further close to the CP. This may suggest that the sigma-mesonic mode forms the soft mode together with the hydrodynamic mode at the CP.

  4. Enhanced detection limit by dark mode perturbation in 2D photonic crystal slab refractive index sensors.

    Science.gov (United States)

    Nicolaou, Costa; Lau, Wah Tung; Gad, Raanan; Akhavan, Hooman; Schilling, Ryan; Levi, Ofer

    2013-12-16

    We demonstrate for the first time a 300nm thick, 300μm × 300μm 2D dielectric photonic crystal slab membrane with a quality factor of 10,600 by coupling light to slightly perturbed dark modes through alternating nano-hole sizes. The newly created fundamental guided resonances greatly reduce nano-fabrication accuracy requirements. Moreover, we created a new layer architecture resulting in electric field enhancement at the interface between the slab and sensing regions, and spectral sensitivity of >800 nm/RIU, that is, >0.8 of the single-mode theoretical upper limit of spectral sensitivity.

  5. Detection of forced oscillations in power systems with multichannel methods

    Energy Technology Data Exchange (ETDEWEB)

    Follum, James D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

    2015-09-30

    The increasing availability of high fidelity, geographically dispersed measurements in power systems improves the ability of researchers and engineers to study dynamic behaviors in the grid. One such behavior that is garnering increased attention is the presence of forced oscillations. Power system engineers are interested in forced oscillations because they are often symptomatic of the malfunction or misoperation of equipment. Though the resulting oscillation is not always large in amplitude, the root cause may be serious. In this report, multi-channel forced oscillation detection methods are developed. These methods leverage previously developed detection approaches based on the periodogram and spectral-coherence. Making use of geographically distributed channels of data is shown to improved detection performance and shorten the delay before an oscillation can be detected in the online environment. Results from simulated and measured power system data are presented.

  6. A high-throughput multiplex method adapted for GMO detection.

    Science.gov (United States)

    Chaouachi, Maher; Chupeau, Gaëlle; Berard, Aurélie; McKhann, Heather; Romaniuk, Marcel; Giancola, Sandra; Laval, Valérie; Bertheau, Yves; Brunel, Dominique

    2008-12-24

    A high-throughput multiplex assay for the detection of genetically modified organisms (GMO) was developed on the basis of the existing SNPlex method designed for SNP genotyping. This SNPlex assay allows the simultaneous detection of up to 48 short DNA sequences (approximately 70 bp; "signature sequences") from taxa endogenous reference genes, from GMO constructions, screening targets, construct-specific, and event-specific targets, and finally from donor organisms. This assay avoids certain shortcomings of multiplex PCR-based methods already in widespread use for GMO detection. The assay demonstrated high specificity and sensitivity. The results suggest that this assay is reliable, flexible, and cost- and time-effective for high-throughput GMO detection.

  7. DETECTION OF CAVITATION IN CENTRIFUGAL PUMP BY VIBRATION METHODS

    Institute of Scientific and Technical Information of China (English)

    NI Yongyan; YUAN Shouqi; PAN Zhongyong; YUAN Jianping

    2008-01-01

    For the purpose of detecting the cavitation of centrifugal pump onsite and real time, the vibration signals on varied operation conditions of both cavitation and non-cavitation obtained through acceleration sensors were analyzed. When cavitation occurs, the cavities near the leading edge of the blade will appear periodic oscillating, which will induce quasi-synchronous vibration. The frequency of the quasi-synchronous vibration symmetrically appears on the two sides of the blade passing frequency, by which the cavitation incipiency can be detected. During the developing process of the cavitation, as the severe complexity of the unsteady flow, it is very difficult to detect the development of cavitation by classical analysis methods. Fractal method of Higuchi is successfully used for detecting the incipiency, fully development of cavitation and the development between them.

  8. Multi-core Processors based Network Intrusion Detection Method

    Directory of Open Access Journals (Sweden)

    Ziqian Wan

    2012-09-01

    Full Text Available It is becoming increasingly hard to build an intrusion detection system (IDS, because of the higher traffic throughput and the rising sophistication of attacking. Scale will be an important issue to address in the intrusion detection area. For hardware, tomorrow’s performance gains will come from multi-core architectures in which a number of CPU executes concurrently. We take the advantage of multi-core processors’ full power for intrusion detection in this work. We present an intrusion detection system based on the Snort open-source IDS that exploits the computational power of MIPS multi-core architecture to offload the costly pattern matching operations from the CPU, and thus increase the system’s processing throughput. A preliminary experiment demonstrates the potential of this system. The experiment results indicate that this method can be used effectively to speed up intrusion detection systems.

  9. Transistor-based particle detection systems and methods

    Science.gov (United States)

    Jain, Ankit; Nair, Pradeep R.; Alam, Muhammad Ashraful

    2015-06-09

    Transistor-based particle detection systems and methods may be configured to detect charged and non-charged particles. Such systems may include a supporting structure contacting a gate of a transistor and separating the gate from a dielectric of the transistor, and the transistor may have a near pull-in bias and a sub-threshold region bias to facilitate particle detection. The transistor may be configured to change current flow through the transistor in response to a change in stiffness of the gate caused by securing of a particle to the gate, and the transistor-based particle detection system may configured to detect the non-charged particle at least from the change in current flow.

  10. An efficient Born normal mode method to compute sensitivity kernels and synthetic seismograms in the Earth

    Science.gov (United States)

    Capdeville, Y.

    2005-11-01

    We present an alternative to the classical mode coupling method scheme often used in global seismology to compute synthetic seismograms in laterally heterogeneous earth model and Frechet derivatives for tomographic inverse problem with the normal modes first-order Born approximation. We start from the first-order Born solution in the frequency domain and we use a numerical scheme for the volume integration, which means that we have to compute the effect of a finite number of scattering points and sum them with the appropriate integration weight. For each scattering point, `source to scattering point' and `scattering point to receivers' expressions are separated before applying a Fourier transform to return to the time domain. Doing so, the perturbed displacement is obtained, for each scattering point, as the convolution of a forward wavefield from the source to the scattering point with a backward wavefield from the scattering integration point to the receiver. For one scattering point and for a given number of time steps, the numerical cost of such a scheme grows as (number of receivers + the number of sources) × (corner frequency)2 to be compared to (number of receivers × the number of sources) × (corner frequency)4 when the classical normal mode coupling algorithm is used. Another interesting point is, when used for Frechet kernel, the computing cost is (almost) independent of the number of parameters used for the inversion. This algorithm is similar to the one obtained when solving the adjoint problem. Validation tests with respect to the spectral element method solution both in the Frechet derivative case and as a synthetic seismogram tool shows a good agreement. In the latter case, we show that non-linearity can be significant even at long periods and when using existing smooth global tomographic models.

  11. MoveSteg: A Method of Network Steganography Detection

    OpenAIRE

    Szczypiorski, Krzysztof; Tyl, Tomasz

    2016-01-01

    This article presents a new method for detecting a source point of time based network steganography - MoveSteg. A steganography carrier could be an example of multimedia stream made with packets. These packets are then delayed intentionally to send hidden information using time based steganography methods. The presented analysis describes a method that allows finding the source of steganography stream in network that is under our management.

  12. MoveSteg: A Method of Network Steganography Detection

    OpenAIRE

    Szczypiorski, Krzysztof; Tyl, Tomasz

    2016-01-01

    This article presents a new method for detecting a source point of time based network steganography - MoveSteg. A steganography carrier could be an example of multimedia stream made with packets. These packets are then delayed intentionally to send hidden information using time based steganography methods. The presented analysis describes a method that allows finding the source of steganography stream in network that is under our management.

  13. A New Bilirubin Concentration Detection Method by Light Reflection

    CERN Document Server

    Subasilar, B

    1999-01-01

    A new and simple method of blood bilirubin detection through light reflection from skin is developed. The basic improvement over the existing methods is in the design of the light emitter and detector geometry which facilitates a two-stream plane parallel homogenous medium solution to the emitting-scatterig radiative transfer equation. The forward peak in the scattering phase function that is characteristic of water droplets and water filled media is accounted for through a proper method named delta-Eddington approximation.

  14. The Maximum Patch Method for Directional Dark Matter Detection

    CERN Document Server

    Henderson, Shawn; Fisher, Peter

    2008-01-01

    Present and planned dark matter detection experiments search for WIMP-induced nuclear recoils in poorly known background conditions. In this environment, the maximum gap statistical method provides a way of setting more sensitive cross section upper limits by incorporating known signal information. We give a recipe for the numerical calculation of upper limits for planned directional dark matter detection experiments, that will measure both recoil energy and angle, based on the gaps between events in two-dimensional phase space.

  15. PERFORMANCE OF IMPULSE NOISE DETECTION METHODS IN REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    Mrs.V.RADHIKA,

    2010-09-01

    Full Text Available Remote sensing (RS images are affected by different types of noises like Gaussian noise, speckle noise and impulse noise. These noises are introduced into the RS images during acquisition or transmission process. The main challenge in impulse noise removal is to suppress the noise as well as to preserve the details (edges. Removal ofthe impulse noise is done by two stages: detection of noisy pixel and replacement of that pixel. Detecting and Removing or reducing impulse noise is a very active research area in image processing. In this paper three different existing detection methods are discussed with the intension of developing a new one.

  16. Radiation detection and measurement concepts, methods and devices

    CERN Document Server

    McGregor, Douglas

    2018-01-01

    This text on radiation detection and measurement is a response to numerous requests expressed by students at various universities, in which the most popularly used books do not provide adequate background material, nor explain matters in understandable terms. This work provides a modern overview of radiation detection devices and radiation measurement methods. The topics selected in the book have been selected on the basis of the author’s many years of experience designing radiation detectors and teaching radiation detection and measurement in a classroom environment.

  17. Method and automated apparatus for detecting coliform organisms

    Science.gov (United States)

    Dill, W. P.; Taylor, R. E.; Jeffers, E. L. (Inventor)

    1980-01-01

    Method and automated apparatus are disclosed for determining the time of detection of metabolically produced hydrogen by coliform bacteria cultured in an electroanalytical cell from the time the cell is inoculated with the bacteria. The detection time data provides bacteria concentration values. The apparatus is sequenced and controlled by a digital computer to discharge a spent sample, clean and sterilize the culture cell, provide a bacteria nutrient into the cell, control the temperature of the nutrient, inoculate the nutrient with a bacteria sample, measures the electrical potential difference produced by the cell, and measures the time of detection from inoculation.

  18. Recent and innovative methods for detection of bacteremia and fungemia

    Energy Technology Data Exchange (ETDEWEB)

    Reller, L.B.

    1983-07-28

    Advances continue to be made in methods for more reliable or more rapid means of detecting bacteremia and fungemia. The importance of blood sample volume and broth dilution has been established in controlled studies. New technology includes the use of resins that remove antimicrobials from blood samples, detection of radioactivity from organisms given radiolabeled substrate, use of dyes that stain microbial DNA and RNA, use of slides coated with growth media, and lysis-centrifugation for trapping microorganisms. Technology now being considered includes counterimmunoelectrophoresis, head-space gas chromatography, electrical impedance, microcalorimetry, and the use of lasers to detect pH changes and turbidity.

  19. Safety assessment and detection methods of genetically modified organisms.

    Science.gov (United States)

    Xu, Rong; Zheng, Zhe; Jiao, Guanglian

    2014-01-01

    Genetically modified organisms (GMOs), are gaining importance in agriculture as well as the production of food and feed. Along with the development of GMOs, health and food safety concerns have been raised. These concerns for these new GMOs make it necessary to set up strict system on food safety assessment of GMOs. The food safety assessment of GMOs, current development status of safety and precise transgenic technologies and GMOs detection have been discussed in this review. The recent patents about GMOs and their detection methods are also reviewed. This review can provide elementary introduction on how to assess and detect GMOs.

  20. Method and apparatus for detecting laminar flow separation and reattachment

    Science.gov (United States)

    Stack, John P. (Inventor); Mangalam, Sivaramakrishnan M. (Inventor)

    1990-01-01

    The invention is a method and apparatus for simultaneously detecting laminar separation and reattachment of a fluid stream such as an airstream from and to the upper surface of an airfoil by simultaneously sensing and comparing a plurality of output signals. Each signal represents the dynamic shear stress at one of an equal number of sensors spaced along a straight line on the surface of the airfoil that extends parallel to the airstream. The output signals are simultaneously compared to detect the sensors across which a reversal in phase of said output signal occurs, said detected sensors being in the region of laminar separation or reattachment.

  1. Machine Learning Methods for Attack Detection in the Smart Grid.

    Science.gov (United States)

    Ozay, Mete; Esnaola, Inaki; Yarman Vural, Fatos Tunay; Kulkarni, Sanjeev R; Poor, H Vincent

    2016-08-01

    Attack detection problems in the smart grid are posed as statistical learning problems for different attack scenarios in which the measurements are observed in batch or online settings. In this approach, machine learning algorithms are used to classify measurements as being either secure or attacked. An attack detection framework is provided to exploit any available prior knowledge about the system and surmount constraints arising from the sparse structure of the problem in the proposed approach. Well-known batch and online learning algorithms (supervised and semisupervised) are employed with decision- and feature-level fusion to model the attack detection problem. The relationships between statistical and geometric properties of attack vectors employed in the attack scenarios and learning algorithms are analyzed to detect unobservable attacks using statistical learning methods. The proposed algorithms are examined on various IEEE test systems. Experimental analyses show that machine learning algorithms can detect attacks with performances higher than attack detection algorithms that employ state vector estimation methods in the proposed attack detection framework.

  2. Evaluation of performance of the Omni mode for detecting video capsule endoscopy images: A multicenter randomized controlled trial.

    Science.gov (United States)

    Hosoe, Naoki; Watanabe, Kenji; Miyazaki, Takako; Shimatani, Masaaki; Wakamatsu, Takahiro; Okazaki, Kazuichi; Esaki, Motohiro; Matsumoto, Takayuki; Abe, Takayuki; Kanai, Takanori; Ohtsuka, Kazuo; Watanabe, Mamoru; Ikeda, Keiichi; Tajiri, Hisao; Ohmiya, Naoki; Nakamura, Masanao; Goto, Hidemi; Tsujikawa, Tomoyuki; Ogata, Haruhiko

    2016-08-01

    Olympus recently developed a new algorithm called Omni mode that discards redundant video capsule endoscopy (VCE) images. The current study aimed to demonstrate the non-inferiority of the Omni mode in terms of true positives (TPs) and the superiority of the Omni mode with regard to reading time against a control (ordinary ES-10 system). This multicenter prospective study included 40 patients with various small bowel diseases. VCE images were evaluated by 7 readers and 3 judging committee members. Two randomly allocated readers assessed the VCE images obtained using the 2 modalities for each patient. The order of the modalities was switched between the 2 readers and the interval between readings by the same reader was 2 weeks. The judging committee predefined clinically relevant lesions as major lesions and irrelevant lesions as minor lesions. The number of TPs for major and minor lesions and the reading times were compared between the modalities. The predefined non-inferiority margin for the TP ratio of the Omni mode compared with the control was 0.9. The estimated TP ratios and 95 % confidence intervals for total, major, and minor lesions were 0.87 (0.80 - 0.95), 0.93 (0.83 - 1.04), and 0.83 (0.74 - 0.94), respectively. Although non-inferiority was not demonstrated, the rate of detection of major lesions was not significantly different between the modalities. The reading time was significantly lower when using the Omni mode than when using the control. The Omni mode may be only appropriate for the assessment of major lesions.

  3. The efficacy of the reverse contrast mode in digital radiography for the detection of proximal dentinal caries

    Energy Technology Data Exchange (ETDEWEB)

    Miri, Shimasadat [Dept. of Endodontics, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Mehrailzadeh, Sandra; Sadri, Donya [School of Dentistry, Islamic Azad University, Tehran (Iran, Islamic Republic of); Motamedi, Mahmood Reza Kalantar [Dept. of Research, School of Dentistry, Isfahan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Soltani, Parisa [Dental Students Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of)

    2015-09-15

    This study evaluated the diagnostic accuracy of the reverse contrast mode in intraoral digital radiography for the detection of proximal dentinal caries, in comparison with the original digital radiographs. Eighty extracted premolars with no clinically apparent caries were selected, and digital radiographs of them were taken separately in standard conditions. Four observers examined the original radiographs and the same radiographs in the reverse contrast mode with the goal of identifying proximal dentinal caries. Microscopic sections 5 µm in thickness were prepared from the teeth in the mesiodistal direction. Four slides prepared from each sample used as the diagnostic gold standard. The data were analyzed using SPSS (α=0.05). Our results showed that the original radiographs in order to identify proximal dentinal caries had the following values for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy, respectively: 72.5%, 90%, 87.2%, 76.5%, and 80.9%. For the reverse contrast mode, however, the corresponding values were 63.1%, 89.4%, 87.1%, 73.5%, and 78.8%, respectively. The sensitivity of original digital radiograph for detecting proximal dentinal caries was significantly higher than that of reverse contrast mode (p<0.05). However, no statistically significant differences were found regarding specificity, positive predictive value, negative predictive value, or accuracy (p>0.05). The sensitivity of the original digital radiograph for detecting proximal dentinal caries was significantly higher than that of the reversed contrast images. However, no statistically significant differences were found between these techniques regarding specificity, positive predictive value, negative predictive value, or accuracy.

  4. Mode decomposition methods for flows in high-contrast porous media. Global-local approach

    KAUST Repository

    Ghommem, Mehdi

    2013-11-01

    In this paper, we combine concepts of the generalized multiscale finite element method (GMsFEM) and mode decomposition methods to construct a robust global-local approach for model reduction of flows in high-contrast porous media. This is achieved by implementing Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) techniques on a coarse grid computed using GMsFEM. The resulting reduced-order approach enables a significant reduction in the flow problem size while accurately capturing the behavior of fully-resolved solutions. We consider a variety of high-contrast coefficients and present the corresponding numerical results to illustrate the effectiveness of the proposed technique. This paper is a continuation of our work presented in Ghommem et al. (2013) [1] where we examine the applicability of POD and DMD to derive simplified and reliable representations of flows in high-contrast porous media on fully resolved models. In the current paper, we discuss how these global model reduction approaches can be combined with local techniques to speed-up the simulations. The speed-up is due to inexpensive, while sufficiently accurate, computations of global snapshots. © 2013 Elsevier Inc.

  5. Mode decomposition based on crystallographic symmetry in the band-unfolding method

    Science.gov (United States)

    Ikeda, Yuji; Carreras, Abel; Seko, Atsuto; Togo, Atsushi; Tanaka, Isao

    2017-01-01

    The band-unfolding method is widely used to calculate the effective band structures of a disordered system from its supercell model. The unfolded band structures show the crystallographic symmetry of the underlying structure, where the difference of chemical components and the local atomic relaxation are ignored. However, it has still been difficult to decompose the unfolded band structures into the modes based on the crystallographic symmetry of the underlying structure, and therefore detailed analyses of the unfolded band structures have been restricted. In this study, a procedure to decompose the unfolded band structures according to the small representations (SRs) of the little groups is developed. The decomposition is performed using the projection operators for SRs derived from the group representation theory. The current method is employed to investigate the phonon band structure of disordered face-centered-cubic Cu0.75Au0.25 , which has large variations of atomic masses and force constants among the atomic sites due to the chemical disorder. In the unfolded phonon band structure, several peculiar behaviors such as discontinuous and split branches are found in the decomposed modes corresponding to specific SRs. They are found to occur because different combinations of the chemical elements contribute to different regions of frequency.

  6. Asymptotic Performance of Sparse Signal Detection Using Convex Programming Method

    Institute of Scientific and Technical Information of China (English)

    LEI Chuan; ZHANG Jun

    2012-01-01

    The detection of sparse signals against background noise is considered.Detecting signals of such kind is difficult since only a small portion of the signal carries information.Prior knowledge is usually assumed to ease detection.In this paper,we consider the general unknown and arbitrary sparse signal detection problem when no prior knowledge is available.Under a Neyman-Pearson hypothesis-testing framework,a new detection scheme is proposed by combining a generalized likelihood ratio test (GLRT)-like test statistic and convex programming methods which directly exploit sparsity in an underdetermined system of linear equations.We characterize large sample behavior of the proposed method by analyzing its asymptotic performance.Specifically,we give the condition for the Chernoff-consistent detection which shows that the proposed method is very sensitive to the (e)2 norm energy of the sparse signals.Both the false alarm rate and the miss rate tend to zero at vanishing signal-to-noise ratio (SNR),as long as the signal energy grows at least logarithmically with the problem dimension.Next we give a large deviation analysis to characterize the error exponent for the Neyman-Pearson detection.We derive the oracle error exponent assuming signal knowledge.Then we explicitly derive the error exponent of the proposed scheme and compare it with the oracle exponent.We complement our study with numerical experiments,showing that the proposed method performs in the vicinity of the likelihood ratio test (LRT) method in the finite sample scenario and the error probability degrades exponentially with the number of observations.

  7. Mode shifting between storage and recall based on novelty detection in oscillating hippocampal circuits

    NARCIS (Netherlands)

    Meeter, M.; Murre, J.M.J.; Talamini, L.M.

    2004-01-01

    It has been suggested that hippocampal mode shifting between a storage and a retrieval state might be under the control of acetylcholine (ACh) levels, as set by an autoregulatory hippocampo-septo-hippocampal loop. The present study investigates how such a mechanism might operate in a large-scale con

  8. Detection methods for legionellae. Possibilities and limitations of detection methods; Niet alle detectiemethoden geschikt voor legionellagroei. Mogelijkheden en beperkingen detectiemethoden

    Energy Technology Data Exchange (ETDEWEB)

    Scheffer, W.

    2011-06-15

    This article provides an overview of existing and new methods for detecting legionella in water. It offers insight in the characteristics and applications of existing and new detection methods. However, it is impossible to assess the value of alternative methods at the moment. That will require additional research. [Dutch] Een overzicht is gemaakt van bestaande en nieuwe methoden om legionella in water aan te tonen. Daarmee wordt inzicht verkregen in de kenmerken en toepassingsmogelijkheden van bestaande en nieuwe detectiemethoden. De waarde van alternatieve methoden in een installatie kan echter nog niet worden beoordeeld. Daarvoor is nader onderzoek nodig.

  9. Compositions and methods for detecting single nucleotide polymorphisms

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Hsin-Chih; Werner, James; Martinez, Jennifer S.

    2016-11-22

    Described herein are nucleic acid based probes and methods for discriminating and detecting single nucleotide variants in nucleic acid molecules (e.g., DNA). The methods include use of a pair of probes can be used to detect and identify polymorphisms, for example single nucleotide polymorphism in DNA. The pair of probes emit a different fluorescent wavelength of light depending on the association and alignment of the probes when hybridized to a target nucleic acid molecule. Each pair of probes is capable of discriminating at least two different nucleic acid molecules that differ by at least a single nucleotide difference. The methods can probes can be used, for example, for detection of DNA polymorphisms that are indicative of a particular disease or condition.

  10. Effects of Feature Extraction and Classification Methods on Cyberbully Detection

    Directory of Open Access Journals (Sweden)

    Esra SARAÇ

    2016-12-01

    Full Text Available Cyberbullying is defined as an aggressive, intentional action against a defenseless person by using the Internet, or other electronic contents. Researchers have found that many of the bullying cases have tragically ended in suicides; hence automatic detection of cyberbullying has become important. In this study we show the effects of feature extraction, feature selection, and classification methods that are used, on the performance of automatic detection of cyberbullying. To perform the experiments FormSpring.me dataset is used and the effects of preprocessing methods; several classifiers like C4.5, Naïve Bayes, kNN, and SVM; and information gain and chi square feature selection methods are investigated. Experimental results indicate that the best classification results are obtained when alphabetic tokenization, no stemming, and no stopwords removal are applied. Using feature selection also improves cyberbully detection performance. When classifiers are compared, C4.5 performs the best for the used dataset.

  11. Method for predicting peptide detection in mass spectrometry

    Science.gov (United States)

    Kangas, Lars [West Richland, WA; Smith, Richard D [Richland, WA; Petritis, Konstantinos [Richland, WA

    2010-07-13

    A method of predicting whether a peptide present in a biological sample will be detected by analysis with a mass spectrometer. The method uses at least one mass spectrometer to perform repeated analysis of a sample containing peptides from proteins with known amino acids. The method then generates a data set of peptides identified as contained within the sample by the repeated analysis. The method then calculates the probability that a specific peptide in the data set was detected in the repeated analysis. The method then creates a plurality of vectors, where each vector has a plurality of dimensions, and each dimension represents a property of one or more of the amino acids present in each peptide and adjacent peptides in the data set. Using these vectors, the method then generates an algorithm from the plurality of vectors and the calculated probabilities that specific peptides in the data set were detected in the repeated analysis. The algorithm is thus capable of calculating the probability that a hypothetical peptide represented as a vector will be detected by a mass spectrometry based proteomic platform, given that the peptide is present in a sample introduced into a mass spectrometer.

  12. Digital Implementation of Method for Discontinuous Current Mode Compensation Of High-Performance Line-Commutated Converters

    CERN Document Server

    Maestri, S; Uicich, G; Gomez Costa, J; Petrocelli, R; CERN. Geneva. TE Department

    2010-01-01

    Many high-performance power converters at CERN are implemented with thyristors, mostly in CCM (Continuous Conduction Mode) due to their better dynamic response. In DCM (Discontinuous Conduction Mode), the converter reduces its small-signal gain, producing a degraded time response which can lead to instability. Several of these converters use digital regulation, allowing the implementation of complex non- linear control techniques. Therefore, a strategy to control the converters in DCM (Discontinuous Conduction Mode) can be implemented, bearing in mind that their standard operation (sampling time, measured signals, acquisition system) can not be drastically changed. This report presents the implementation of a new method to control line-commutated converters in discontinuous conduction mode (DCM). The method is based on the modfication of the thyristor's ring angle _ using a linear approximation, yielding nearly the same dynamic performance as in continuous conduction mode. The _ring angle is corrected by addi...

  13. An infrared spectroscopy method to detect ammonia in gastric juice.

    Science.gov (United States)

    Giovannozzi, Andrea M; Pennecchi, Francesca; Muller, Paul; Balma Tivola, Paolo; Roncari, Silvia; Rossi, Andrea M

    2015-11-01

    Ammonia in gastric juice is considered a potential biomarker for Helicobacter pylori infection and as a factor contributing to gastric mucosal injury. High ammonia concentrations are also found in patients with chronic renal failure, peptic ulcer disease, and chronic gastritis. Rapid and specific methods for ammonia detection are urgently required by the medical community. Here we present a method to detect ammonia directly in gastric juice based on Fourier transform infrared spectroscopy. The ammonia dissolved in biological liquid samples as ammonium ion was released in air as a gas by the shifting of the pH equilibrium of the ammonium/ammonia reaction and was detected in line by a Fourier transform infrared spectroscopy system equipped with a gas cell for the quantification. The method developed provided high sensitivity and selectivity in ammonia detection both in pure standard solutions and in a simulated gastric juice matrix over the range of diagnostic concentrations tested. Preliminary analyses were also performed on real gastric juice samples from patients with gastric mucosal injury and with symptoms of H. pylori infection, and the results were in agreement with the clinicopathology information. The whole analysis, performed in less than 10 min, can be directly applied on the sample without extraction procedures and it ensures high specificity of detection because of the ammonia fingerprint absorption bands in the infrared spectrum. This method could be easily used with endoscopy instrumentation to provide information in real time and would enable the endoscopist to improve and integrate gastroscopic examinations.

  14. Novel dual-mode immunomagnetic method for studying reactivation of nerve agent-inhibited butyrylcholinesterase.

    Science.gov (United States)

    Abney, Carter W; Knaack, Jennifer L S; Ali, Ahmed A I; Johnson, Rudolph C

    2013-05-20

    A novel immunomagnetic method has been developed for the simultaneous measurement of organophosphorus nerve agent (OPNA) adducts to butyrylcholinesterase (BuChE) and free OPNAs in serum. This new approach, deemed dual-mode immunomagnetic analysis (Dual-Mode IMA), combines immunomagnetic separation (IMS) and immunomagnetic scavenging (IMSc) and has been used to measure the effectiveness of cholinesterase reactivators on OPNA-inhibited BuChE in serum. BuChE inhibited by the nerve agent VX, uninhibited BuChE, and unbound VX were measured up to 1 h after the addition of oxime reactivators pralidoxime (2-PAM) and obidoxime. IMS experiments consisted of extracting BuChE and VX-BuChE serum adducts using antibutyrylcholinesterase monoclonal antibodies conjugated to protein-G ferromagnetic particles. In a parallel set of experiments using IMSc, BuChE-coated magnetic beads were used to extract free VX from protein-depleted serum. Adducts from both IMS and IMSc were analyzed using a published IMS liquid chromatography tandem mass spectrometry (IMS-LC-MS/MS) protocol, which has also been demonstrated with other OPNAs. By applying this Dual-Mode IMA approach, 2-PAM was observed to be more potent than obidoxime in reactivating VX-adducted BuChE. VX-BuChE peptide concentrations initially measured at 19.7 ± 0.7 ng/mL decreased over 1 h to 10.6 ± 0.6 ng/mL when reactivated with 2-PAM and 14.4 ± 1.2 ng/mL when reactivated with obidoxime. These experiments also show that previously published IMS-LC-MS/MS analyses are compatible with serum treated with oximes. Dual-Mode IMA is the first immunoaffinity method developed for the simultaneous measurement of OPNA adducted BuChE, unadducted BuChE, and free nerve agent in serum and is a promising new tool for studying reactivator effectiveness on cholinesterases inhibited by nerve agents.

  15. Statistical method for detecting structural change in the growth process.

    Science.gov (United States)

    Ninomiya, Yoshiyuki; Yoshimoto, Atsushi

    2008-03-01

    Due to competition among individual trees and other exogenous factors that change the growth environment, each tree grows following its own growth trend with some structural changes in growth over time. In the present article, a new method is proposed to detect a structural change in the growth process. We formulate the method as a simple statistical test for signal detection without constructing any specific model for the structural change. To evaluate the p-value of the test, the tube method is developed because the regular distribution theory is insufficient. Using two sets of tree diameter growth data sampled from planted forest stands of Cryptomeria japonica in Japan, we conduct an analysis of identifying the effect of thinning on the growth process as a structural change. Our results demonstrate that the proposed method is useful to identify the structural change caused by thinning. We also provide the properties of the method in terms of the size and power of the test.

  16. Study on UPF Harmonic Current Detection Method Based on DSP

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, H J [Northwestern Polytechnical University, Xi' an 710072 (China); Pang, Y F [Xi' an University of Technology, Xi' an 710048 (China); Qiu, Z M [Xi' an University of Technology, Xi' an 710048 (China); Chen, M [Northwestern Polytechnical University, Xi' an 710072 (China)

    2006-10-15

    Unity power factor (UPF) harmonic current detection method applied to active power filter (APF) is presented in this paper. The intention of this method is to make nonlinear loads and active power filter in parallel to be an equivalent resistance. So after compensation, source current is sinusoidal, and has the same shape of source voltage. Meanwhile, there is no harmonic in source current, and the power factor becomes one. The mathematic model of proposed method and the optimum project for equivalent low pass filter in measurement are presented. Finally, the proposed detection method applied to a shunt active power filter experimental prototype based on DSP TMS320F2812 is developed. Simulation and experiment results indicate the method is simple and easy to implement, and can obtain the real-time calculation of harmonic current exactly.

  17. A NEW MOMENT METHOD FOR THE FAST AND ACCURATE ANALYSIS OF NORMAL MODE HELICAL ANTENNAS

    Institute of Scientific and Technical Information of China (English)

    Ji Yicai; Sun Baohua; Liu Qizhong

    2001-01-01

    In this letter, a new moment method using helical segments is presented to model Normal Mode Helical Antenna (NMHA). Using this method, the NMHA can be modeled by a few segments. The current distributions and radiation patterns of some NMHAs are calculated.A comparison is made between results obtained using this helical segment algorithm and a linear segment algorithm, and the results of the two algorithms agree fairly well. When calculating the impedance matrix [Z], all the elements of the matrix can be obtained by only calculating a few elements with the application of the symmetric and periodic characteristics of the NMHA.Therefore, the CPU time and the memory storage are significantly reduced, with the accuracy and speed enhanced.

  18. Complex Mode Frequency Iteration Method for Flutter Analysis of 2-DOF Systems

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    For a vibration system with 2-DOF of bend and torsion, itscritical flutter wind speed can be calculated by using complex mode frequency iteration (CMFI) method based on MatLab 5.2, the results of which are in agree with those acquired by wind tunnel test. Not only critical flutter wind speed, but also vibration characteristic of a system under different wind speeds can be determined. CMFI method is suitable for both of separated-flow torsional flutter and classic coupling flutter analysis, which is presented by flutter analysis of an ideal thin plate and a bluff bridge deck. Furthermore, it is proved through the investigation of the relationship between flutter derivatives and its critical flutter wind speed that coupling aerodynamic derivatives are necessary for classic coupling flutter to occur.

  19. Exciting (and detecting) gravitational waves from the tidally produced f-modes in highly eccentric neutron star binaries

    Science.gov (United States)

    Chirenti, Cecilia; Gold, Roman; Miller, M. Coleman

    2017-08-01

    After the first recent detections of gravitational waves from binary black holes, we expect to observe next gravitational radiation from neutron stars in the near future. Most interestingly, the signal from neutron star binaries could also carry information about the equation of state of cold, catalyzed, dense matter in the interior of neutron stars, which is in a regime not accessible to nuclear and particle physics experiments on Earth. For analyzing this information, more advanced gravitational wave detectors will be needed, such as third-generation detectors like the Einstein Telescope or the Cosmic Explorer. Besides the gravitational wave signal produced by the orbital motion and merger of the binary, a rich spectrum of characteristic fluid oscillations is expected to be produced with low amplitude in the ringdown. The frequencies and physical properties of these modes have been extensively studied in linear perturbation theory (both Newtonian and relativistic) and they have already been found in numerical relativity simulations of isolated neutron stars and of hypermassive remnants of double neutron star mergers. Due to the high frequency of the fundamental (f-)modes, of the order of 1-2 kHz, the resonant excitation of these modes is not expected to be detectable in circular binaries. However, highly eccentric binaries could have the potential for exciting f-modes in their close passages, and recent numerical relativity simulations indicate that the energy deposited in the f-modes could be up to two orders of magnitude greater than predicted in the linear theory. The merger of highly eccentric neutron star binaries will be rare events, but we estimate that up to several tens could be detected per year out to the redshifts ~2-6 accessible with third-generation instruments. Finally, we note that the information from the amplitude, frequency and damping time of the f-modes can be used for simultaneously measuring the masses, moments of inertia and tidal Love

  20. An Effective Method for Protecting Native API Hook Attacks in User-mode

    Directory of Open Access Journals (Sweden)

    K. Muthumanickam

    2015-01-01

    Full Text Available Today, many modern malware developers is taking the advantage of Application Programming Interface (API hook technique to take the control of the victim computer which making it difficult to detect their presence. Because of the sophistication of rootkit tools, a remote attacker can use native API to compromise any computer which can later be used for many illegal activities such as sniffing network lines, capturing passwords, sending spam and DDoS attack, etc. Thus to protect end-system by identifying and preventing native API malicious code hooking is a challenging problem to the defenders. Today, many different malware-analysis tools incur specific features against malwares but manual and error-prone. In this study, we proposed a behavior-based monitoring detection system to effectively deal native API hooks in user-mode. Unlike other malware identification techniques, our approach involved dynamically analyzing the behavior of native API call hooking malwares. Comparing our experimental evaluation results with existing tools show better performance with no false positive.