Tracking variable sedimentation rates in orbitally forced paleoclimate proxy series

Science.gov (United States)

Li, M.; Kump, L. R.; Hinnov, L.

2017-12-01

This study addresses two fundamental issues in cyclostratigraphy: quantitative testing of orbital forcing in cyclic sedimentary sequences and tracking variable sedimentation rates. The methodology proposed here addresses these issues as an inverse problem, and estimates the product-moment correlation coefficient between the frequency spectra of orbital solutions and paleoclimate proxy series over a range of "test" sedimentation rates. It is inspired by the ASM method (1). The number of orbital parameters involved in the estimation is also considered. The method relies on the hypothesis that orbital forcing had a significant impact on the paleoclimate proxy variations, and thus is also tested. The null hypothesis of no astronomical forcing is evaluated using the Beta distribution, for which the shape parameters are estimated using a Monte Carlo simulation approach. We introduce a metric to estimate the most likely sedimentation rate using the product-moment correlation coefficient, H0 significance level, and the number of contributing orbital parameters, i.e., the CHO value. The CHO metric is applied with a sliding window to track variable sedimentation rates along the paleoclimate proxy series. Two forward models with uniform and variable sedimentation rates are evaluated to demonstrate the robustness of the method. The CHO method is applied to the classical Late Triassic Newark depth rank series; the estimated sedimentation rates match closely with previously published sedimentation rates and provide a more highly time-resolved estimate (2,3). References: (1) Meyers, S.R., Sageman, B.B., Amer. J. Sci., 307, 773-792, 2007; (2) Kent, D.V., Olsen, P.E., Muttoni, G., Earth-Sci. Rev.166, 153-180, 2017; (3) Li, M., Zhang, Y., Huang, C., Ogg, J., Hinnov, L., Wang, Y., Zou, Z., Li, L., 2017. Earth Plant. Sc. Lett. doi:10.1016/j.epsl.2017.07.015

Rate control and quality assurance during rhythmic force tracking.

Science.gov (United States)

Huang, Cheng-Ya; Su, Jyong-Huei; Hwang, Ing-Shiou

2014-02-01

Movement characteristics can be coded in the single neurons or in the summed activity of neural populations. However, whether neural oscillations are conditional to the frequency demand and task quality of rhythmic force regulation is still unclear. This study was undertaken to investigate EEG dynamics and behavior correlates during force-tracking at different target rates. Fourteen healthy volunteers conducted load-varying isometric abduction of the index finger by coupling the force output to sinusoidal targets at 0.5 Hz, 1.0 Hz, and 2.0 Hz. Our results showed that frequency demand significantly affected EEG delta oscillation (1-4 Hz) in the C3, CP3, CPz, and CP4 electrodes, with the greatest delta power and lowest delta peak around 1.5 Hz for slower tracking at 0.5 Hz. Those who had superior tracking congruency also manifested enhanced alpha oscillation (8-12 Hz). Alpha rhythms of the skilled performers during slow tracking spread through the whole target cycle, except for the phase of direction changes. However, the alpha rhythms centered at the mid phase of a target cycle with increasing target rate. In conclusion, our findings clearly suggest two advanced roles of cortical oscillation in rhythmic force regulation. Rate-dependent delta oscillation involves a paradigm shift in force control under different time scales. Phasic organization of alpha rhythms during rhythmic force tracking is related to behavioral success underlying the selective use of bimodal controls (feedback and feedforward processes) and the timing of attentional focus on the target's peak velocity. Copyright © 2013 Elsevier B.V. All rights reserved.

Methods and sensitivity for pass-by measurement of track decay rates

NARCIS (Netherlands)

Dittrich, M.G.

2012-01-01

Track decay rates are measured to characterize the track dynamics for railway noise type testing, but also for other purposes in relation to railway noise. They are often measured statically using hammer response functions on unloaded track, but can also be derived from rail vibrations on loaded

High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera Tracking

Science.gov (United States)

Liss, J.; Dunagan, S. E.; Johnson, R. R.; Chang, C. S.; LeBlanc, S. E.; Shinozuka, Y.; Redemann, J.; Flynn, C. J.; Segal-Rosenhaimer, M.; Pistone, K.; Kacenelenbogen, M. S.; Fahey, L.

2016-12-01

High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera TrackingThe NASA Ames Sun-photometer-Satellite Group, DOE, PNNL Atmospheric Sciences and Global Change Division, and NASA Goddard's AERONET (AErosol RObotic NETwork) team recently collaborated on the development of a new airborne sunphotometry instrument that provides information on gases and aerosols extending far beyond what can be derived from discrete-channel direct-beam measurements, while preserving or enhancing many of the desirable AATS features (e.g., compactness, versatility, automation, reliability). The enhanced instrument combines the sun-tracking ability of the current 14-Channel NASA Ames AATS-14 with the sky-scanning ability of the ground-based AERONET Sun/sky photometers, while extending both AATS-14 and AERONET capabilities by providing full spectral information from the UV (350 nm) to the SWIR (1,700 nm). Strengths of this measurement approach include many more wavelengths (isolated from gas absorption features) that may be used to characterize aerosols and detailed (oversampled) measurements of the absorption features of specific gas constituents. The Sky Scanning Sun Tracking Airborne Radiometer (3STAR) replicates the radiometer functionality of the AATS-14 instrument but incorporates modern COTS technologies for all instruments subsystems. A 19-channel radiometer bundle design is borrowed from a commercial water column radiance instrument manufactured by Biospherical Instruments of San Diego California (ref, Morrow and Hooker)) and developed using NASA funds under the Small Business Innovative Research (SBIR) program. The 3STAR design also incorporates the latest in robotic motor technology embodied in Rotary actuators from Oriental motor Corp. having better than 15 arc seconds of positioning accuracy. Control system was designed, tested and simulated using a Hybrid-Dynamical modeling methodology. The design also replaces the classic quadrant detector tracking sensor with a

Track profile and range studies of heavy and light ions in CR-39: effect of thermal pre-treatment on etching characteristics

International Nuclear Information System (INIS)

Al-Najjar, S.A.R.; Bull, R.K.; Durrani, S.A.

1982-01-01

Sheets of CR 39 have been irradiated with 20 Ne, 32 S, 40 Ar, 56 Fe and 63 Cu ions at normal incidence to the surface of the sheets and at normal incidence to the edges. The profiles of the etched tracks have been observed side-on and measurements made of the variation of V (the ratio of track to bulk etching velocities) along the tracks and of the fully etched range of the tracks. Heating the plastic at 100 0 C prior to etching produces zones within the plastic having different bulk etching rates Vsub(B). An outer zone of low Vsub(B) is followed by a zone of much higher Vsub(B). This allows tracks to be readily etched to very large diameters, comparable in size to the breakdown spots produced by electrochemical etching. (author)

Long-term temporal tracking of speech rate affects spoken-word recognition.

Science.gov (United States)

Baese-Berk, Melissa M; Heffner, Christopher C; Dilley, Laura C; Pitt, Mark A; Morrill, Tuuli H; McAuley, J Devin

2014-08-01

Humans unconsciously track a wide array of distributional characteristics in their sensory environment. Recent research in spoken-language processing has demonstrated that the speech rate surrounding a target region within an utterance influences which words, and how many words, listeners hear later in that utterance. On the basis of hypotheses that listeners track timing information in speech over long timescales, we investigated the possibility that the perception of words is sensitive to speech rate over such a timescale (e.g., an extended conversation). Results demonstrated that listeners tracked variation in the overall pace of speech over an extended duration (analogous to that of a conversation that listeners might have outside the lab) and that this global speech rate influenced which words listeners reported hearing. The effects of speech rate became stronger over time. Our findings are consistent with the hypothesis that neural entrainment by speech occurs on multiple timescales, some lasting more than an hour. © The Author(s) 2014.

The evolutionary rate dynamically tracks changes in HIV-1 epidemics

Energy Technology Data Exchange (ETDEWEB)

Maljkovic-berry, Irina [Los Alamos National Laboratory; Athreya, Gayathri [Los Alamos National Laboratory; Daniels, Marcus [Los Alamos National Laboratory; Bruno, William [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory; Kuiken, Carla [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory

2009-01-01

Large-sequence datasets provide an opportunity to investigate the dynamics of pathogen epidemics. Thus, a fast method to estimate the evolutionary rate from large and numerous phylogenetic trees becomes necessary. Based on minimizing tip height variances, we optimize the root in a given phylogenetic tree to estimate the most homogenous evolutionary rate between samples from at least two different time points. Simulations showed that the method had no bias in the estimation of evolutionary rates and that it was robust to tree rooting and topological errors. We show that the evolutionary rates of HIV-1 subtype B and C epidemics have changed over time, with the rate of evolution inversely correlated to the rate of virus spread. For subtype B, the evolutionary rate slowed down and tracked the start of the HAART era in 1996. Subtype C in Ethiopia showed an increase in the evolutionary rate when the prevalence increase markedly slowed down in 1995. Thus, we show that the evolutionary rate of HIV-1 on the population level dynamically tracks epidemic events.

Evaluation of Real-Time Hand Motion Tracking Using a Range Camera and the Mean-Shift Algorithm

Science.gov (United States)

Lahamy, H.; Lichti, D.

2011-09-01

Several sensors have been tested for improving the interaction between humans and machines including traditional web cameras, special gloves, haptic devices, cameras providing stereo pairs of images and range cameras. Meanwhile, several methods are described in the literature for tracking hand motion: the Kalman filter, the mean-shift algorithm and the condensation algorithm. In this research, the combination of a range camera and the simple version of the mean-shift algorithm has been evaluated for its capability for hand motion tracking. The evaluation was assessed in terms of position accuracy of the tracking trajectory in x, y and z directions in the camera space and the time difference between image acquisition and image display. Three parameters have been analyzed regarding their influence on the tracking process: the speed of the hand movement, the distance between the camera and the hand and finally the integration time of the camera. Prior to the evaluation, the required warm-up time of the camera has been measured. This study has demonstrated the suitability of the range camera used in combination with the mean-shift algorithm for real-time hand motion tracking but for very high speed hand movement in the traverse plane with respect to the camera, the tracking accuracy is low and requires improvement.

Tracks FAQs: How Do I Link Asthma Rates And Air Quality Data?

Centers for Disease Control (CDC) Podcasts

2011-07-07

In this podcast, CDC Tracking experts discuss how to linkasthma rates and air quality data. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.  Created: 7/7/2011 by National Center for Environmental Health, Division of Environmental Hazards and Health Effects, Environmental Health Tracking Branch.   Date Released: 7/7/2011.

Three-Dimensional Triplet Tracking for LHC and Future High Rate Experiments

CERN Document Server

Schöning, Andre

2014-10-20

The hit combinatorial problem is a main challenge for track reconstruction and triggering at high rate experiments. At hadron colliders the dominant fraction of hits is due to low momentum tracks for which multiple scattering (MS) effects dominate the hit resolution. MS is also the dominating source for hit confusion and track uncertainties in low energy precision experiments. In all such environments, where MS dominates, track reconstruction and fitting can be largely simplified by using three-dimensional (3D) hit-triplets as provided by pixel detectors. This simplification is possible since track uncertainties are solely determined by MS if high precision spatial information is provided. Fitting of hit-triplets is especially simple for tracking detectors in solenoidal magnetic fields. The over-constrained 3D-triplet method provides a complete set of track parameters and is robust against fake hit combinations. The triplet method is ideally suited for pixel detectors where hits can be treated as 3D-space poi...

Analytically calculated post-Keplerian range and range-rate perturbations: the solar Lense-Thirring effect and BepiColombo

Science.gov (United States)

Iorio, Lorenzo

2018-05-01

We analytically calculate the time series for the perturbations Δ ρ \\left(t\\right), Δ \\dot{ρ }\\left(t\\right) induced by a general disturbing acceleration A on the mutual range ρ and range-rate \\dot{ρ } of two test particles A, B orbiting the same spinning body. We apply it to the general relativistic Lense-Thirring effect, due to the primary's spin S, and the classical perturbation arising from its quadrupole mass moment J2 for arbitrary orbital geometries and orientation of the source's symmetry axis {\\hat{S}}. The Earth-Mercury range and range-rate are nominally affected by the Sun's gravitomagnetic field to the 10 m, 10-3 cm s-1 level, respectively, during the extended phase (2026-2028) of the forthcoming BepiColombo mission to Mercury whose expected tracking accuracy is of the order of ≃0.1 m, 2 × 10-4 cm s-1. The competing signatures due to the solar quadrupole J_2^{\\odot }, if modelled at the σ _{J_2^{\\odot }}˜eq 10^{-9} level of the latest planetary ephemerides INPOP17a, are nearly 10 times smaller than the relativistic gravitomagnetic effects. The position and velocity vectors \\boldsymbol {r}, \\boldsymbol {v} of Mercury and Earth are changed by the solar Lense-Thirring effect by about 10 m, 1.5 m and 10-3 cm s-1, 10-5 cm s-1, respectively, over 2 yr; neglecting such shifts may have an impact on long-term integrations of the inner Solar system dynamics over ˜Gyr time-scales.

High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

Science.gov (United States)

Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

2016-01-01

We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

Three-dimensional triplet tracking for LHC and future high rate experiments

International Nuclear Information System (INIS)

Schöning, A

2014-01-01

The hit combinatorial problem is a main challenge for track reconstruction and triggering at high rate experiments. At hadron colliders the dominant fraction of hits is due to low momentum tracks for which multiple scattering (MS) effects dominate the hit resolution. MS is also the dominating source for hit confusion and track uncertainties in low energy precision experiments. In all such environments, where MS dominates, track reconstruction and fitting can be largely simplified by using three-dimensional (3D) hit-triplets as provided by pixel detectors. This simplification is possible since track uncertainties are solely determined by MS if high precision spatial information is provided. Fitting of hit-triplets is especially simple for tracking detectors in solenoidal magnetic fields. The over-constrained 3D-triplet method provides a complete set of track parameters and is robust against fake hit combinations. Full tracks can be reconstructed step-wise by connecting hit triplet combinations from different layers, thus heavily reducing the combinatorial problem and accelerating track linking. The triplet method is ideally suited for pixel detectors where hits can be treated as 3D-space points. With the advent of relatively cheap and industrially available CMOS-sensors the construction of highly granular full scale pixel tracking detectors seems to be possible also for experiments at LHC or future high energy (hadron) colliders. In this paper tracking performance studies for full-scale pixel detectors, including their optimisation for 3D-triplet tracking, are presented. The results obtained for different types of tracker geometries and different reconstruction methods are compared. The potential of reducing the number of tracking layers and - along with that - the material budget using this new tracking concept is discussed. The possibility of using 3D-triplet tracking for triggering and fast online reconstruction is highlighted

The impact of cine EPID image acquisition frame rate on markerless soft-tissue tracking

Energy Technology Data Exchange (ETDEWEB)

Yip, Stephen, E-mail: syip@lroc.harvard.edu; Rottmann, Joerg; Berbeco, Ross [Department of Radiation Oncology, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

2014-06-15

Purpose: Although reduction of the cine electronic portal imaging device (EPID) acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor autotracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87 Hz with an amorphous silicon portal imager (AS1000, Varian Medical Systems, Palo Alto, CA). The maximum frame rate of 12.87 Hz is imposed by the EPID. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for autotracking. The difference between the programmed and autotracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at 11 field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise are correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the autotracking errors increased at frame rates lower than 4.29 Hz. Above 4.29 Hz, changes in errors were negligible withδ < 1.60 mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R = 0.94) and patient studies (R = 0.72). Moderate to poor correlation was found between image noise and tracking error with R −0.58 and −0.19 for both studies, respectively. Conclusions: Cine EPID

The impact of cine EPID image acquisition frame rate on markerless soft-tissue tracking

International Nuclear Information System (INIS)

Yip, Stephen; Rottmann, Joerg; Berbeco, Ross

2014-01-01

Purpose: Although reduction of the cine electronic portal imaging device (EPID) acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor autotracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87 Hz with an amorphous silicon portal imager (AS1000, Varian Medical Systems, Palo Alto, CA). The maximum frame rate of 12.87 Hz is imposed by the EPID. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for autotracking. The difference between the programmed and autotracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at 11 field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise are correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the autotracking errors increased at frame rates lower than 4.29 Hz. Above 4.29 Hz, changes in errors were negligible withδ < 1.60 mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R = 0.94) and patient studies (R = 0.72). Moderate to poor correlation was found between image noise and tracking error with R −0.58 and −0.19 for both studies, respectively. Conclusions: Cine EPID

Along-track geopotential difference and deflection of the vertical from grace range rate : Use of GEOGRACE

NARCIS (Netherlands)

Tangdamrongsub, N.; Hwang, Cheinway

2016-01-01

We present a theory and numerical algorithm to directly determine the time-varying along-track geopotential difference and deflection of the vertical at the Gravity Recovery and Climate Experiment (GRACE) satellite altitude. The determination was implemented using the GEOGRACE computer program

Interrelated temperature dependence of bulk etch rate and track length saturation time in CR-39 detector

International Nuclear Information System (INIS)

Azooz, A.A.; Al-Jubbori, M.A.

2013-01-01

Highlights: • New empirical parameterization of CR-39 bulk etch rate. • Bulk etch rates measurements using two different methods give consistent results. • Temperature independence of track saturation length. • Two empirical relation between bulk etch rate and temperature are suggested. • Simple inverse relation between bulk etch rate and track saturation time. -- Abstract: Experimental measurements of the etching solution temperature dependence of bulk etch rate using two independent methods revealed a few interesting properties. It is found that while the track saturation length is independent of etching temperature, the etching time needed to reach saturation is strongly temperature-dependent. It is demonstrated that there is systematic simple inverse relation between track saturation time, and etching solution temperature. In addition, and although, the relation between the bulk etch rate and etching solution temperature can be reasonably described by a modified form of the Arrhenius equation, better fits can be obtained by another equation suggested in this work

Storm Identification, Tracking and Forecasting Using High-Resolution Images of Short-Range X-Band Radar

Directory of Open Access Journals (Sweden)

Sajid Shah

2015-05-01

Full Text Available Rain nowcasting is an essential part of weather monitoring. It plays a vital role in human life, ranging from advanced warning systems to scheduling open air events and tourism. A nowcasting system can be divided into three fundamental steps, i.e., storm identification, tracking and nowcasting. The main contribution of this work is to propose procedures for each step of the rain nowcasting tool and to objectively evaluate the performances of every step, focusing on two-dimension data collected from short-range X-band radars installed in different parts of Italy. This work presents the solution of previously unsolved problems in storm identification: first, the selection of suitable thresholds for storm identification; second, the isolation of false merger (loosely-connected storms; and third, the identification of a high reflectivity sub-storm within a large storm. The storm tracking step of the existing tools, such as TITANand SCIT, use only up to two storm attributes, i.e., center of mass and area. It is possible to use more attributes for tracking. Furthermore, the contribution of each attribute in storm tracking is yet to be investigated. This paper presents a novel procedure called SALdEdA (structure, amplitude, location, eccentricity difference and areal difference for storm tracking. This work also presents the contribution of each component of SALdEdA in storm tracking. The second order exponential smoothing strategy is used for storm nowcasting, where the growth and decay of each variable of interest is considered to be linear. We evaluated the major steps of our method. The adopted techniques for automatic threshold calculation are assessed with a 97% goodness. False merger and sub-storms within a cluster of storms are successfully handled. Furthermore, the storm tracking procedure produced good results with an accuracy of 99.34% for convective events and 100% for stratiform events.

Estimation of track registration efficiency in solution medium and study of gamma irradiation effects on the bulk-etch rate and the activation energy for bulk etching of CR-39 (DOP) Solid State Nuclear Track Detector

International Nuclear Information System (INIS)

Kalsi, P.C.

2010-01-01

The fission track registration efficiency of diethylene glycol bis allyl carbonate (dioctyl phthalate doped) (CR-39 (DOP)) solid state nuclear track detector (SSNTD) in solution medium (K wet ) has been experimentally determined and is found to be (9.7 ± 0.5).10 -4 cm. This is in good agreement with the values of other SSNTDs. The gamma irradiation effects in the dose range of 50.0-220.0 kGy on the bulk etch rate, V b and the activation energy for bulk etching, E of this solid state nuclear track detector (SSNTD) have also been studied. It is observed that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation

Calibration of track detectors and measurement of radon exhalation rate from solid samples

International Nuclear Information System (INIS)

Singh, Ajay Kumar; Jojo, P.J.; Prasad, Rajendra; Khan, A.J.; Ramachandran, T.V.

1997-01-01

CR-39 and LR-115 type II track detectors to be used for radon exhalation measurements have been calibrated. The configurations fitted with detectors in Can technique in the open cup mode are cylindrical plastic cup (PC) and conical plastic cup (CPC). The experiment was performed in radon exposure chamber having monodisperse aerosols of 0.2 μm size, to find the relationship between track density and the radon concentration. The calibration factors for PC and CPC type dosimeters with LR-115 type II detector were found to be 0.056 and 0.083 tracks cm -2 d -1 (Bqm -3 ) -1 respectively, while with CR-39 detector the values were 0.149 and 0.150 tracks cm -2 d -1 (Bq m -3 ) -1 . Employing the Can technique, measurements of exhalation rates from solid samples used as construction materials, are undertaken. Radon exhalation rate is found to be minimum in cement samples while in fly ash it is not enhanced as compared to coal samples. (author)

SU-E-J-112: The Impact of Cine EPID Image Acquisition Frame Rate On Markerless Soft-Tissue Tracking

Energy Technology Data Exchange (ETDEWEB)

Yip, S; Rottmann, J; Berbeco, R [Brigham and Women' s Hospital, Boston, MA (United States)

2014-06-01

Purpose: Although reduction of the cine EPID acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor auto-tracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87Hz on an AS1000 portal imager. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for auto-tracking. The difference between the programmed and auto-tracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at eleven field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise were correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the auto-tracking errors increased at frame rates lower than 4.29Hz. Above 4.29Hz, changes in errors were negligible with δ<1.60mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R=0.94) and patient studies (R=0.72). Moderate to poor correlation was found between image noise and tracking error with R -0.58 and -0.19 for both studies, respectively. Conclusion: An image acquisition frame rate of at least 4.29Hz is recommended for cine EPID tracking. Motion blurring in images with frame rates below 4.39Hz can substantially reduce the

SU-E-J-112: The Impact of Cine EPID Image Acquisition Frame Rate On Markerless Soft-Tissue Tracking

International Nuclear Information System (INIS)

Yip, S; Rottmann, J; Berbeco, R

2014-01-01

Purpose: Although reduction of the cine EPID acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor auto-tracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87Hz on an AS1000 portal imager. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for auto-tracking. The difference between the programmed and auto-tracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at eleven field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise were correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the auto-tracking errors increased at frame rates lower than 4.29Hz. Above 4.29Hz, changes in errors were negligible with δ<1.60mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R=0.94) and patient studies (R=0.72). Moderate to poor correlation was found between image noise and tracking error with R -0.58 and -0.19 for both studies, respectively. Conclusion: An image acquisition frame rate of at least 4.29Hz is recommended for cine EPID tracking. Motion blurring in images with frame rates below 4.39Hz can substantially reduce the

Precision tracking at high background rates with the ATLAS muon spectrometer

CERN Document Server

Hertenberger, Ralf; The ATLAS collaboration

2012-01-01

Since start of data taking the ATLAS muon spectrometer performs according to specification. End of this decade after the luminosity upgrade of LHC by a factor of ten the proportionally increasing background rates require the replacement of the detectors in the most forward part of the muon spectrometer to ensure high quality muon triggering and tracking at background hit rates of up to 15,kHz/cm$^2$. Square meter sized micromegas detectors together with improved thin gap trigger detectors are suggested as replacement. Micromegas detectors are intrinsically high rate capable. A single hit spatial resolution below 40,$mu$m has been shown for 250,$mu$m anode strip pitch and perpendicular incidence of high energy muons or pions. The ongoing development of large micromegas structures and their investigation under non-perpendicular incidence or in high background environments requires precise and reliable monitoring of muon tracks. A muon telescope consisting of six small micromegas works reliably and is presently ...

Long range position and orientation tracking system

International Nuclear Information System (INIS)

Armstrong, G.A.; Jansen, J.F.; Burks, B.L.; Bernacki, B.E.; Nypaver, D.J.

1995-01-01

The long range position and orientation tracking system (LRPOTS) will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the man-ways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the Content Mobilization System (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation

Long-range position and orientation tracking system

International Nuclear Information System (INIS)

Armstrong, G.A.; Jansen, J.F.; Burks, B.L.

1995-01-01

The long-range position and orientation tracking system will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the manways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the content mobilization system (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation

Tracking Control of Hysteretic Piezoelectric Actuator using Adaptive Rate-Dependent Controller.

Science.gov (United States)

Tan, U-Xuan; Latt, Win Tun; Widjaja, Ferdinan; Shee, Cheng Yap; Riviere, Cameron N; Ang, Wei Tech

2009-03-16

With the increasing popularity of actuators involving smart materials like piezoelectric, control of such materials becomes important. The existence of the inherent hysteretic behavior hinders the tracking accuracy of the actuators. To make matters worse, the hysteretic behavior changes with rate. One of the suggested ways is to have a feedforward controller to linearize the relationship between the input and output. Thus, the hysteretic behavior of the actuator must first be modeled by sensing the relationship between the input voltage and output displacement. Unfortunately, the hysteretic behavior is dependent on individual actuator and also environmental conditions like temperature. It is troublesome and costly to model the hysteresis regularly. In addition, the hysteretic behavior of the actuators also changes with age. Most literature model the actuator using a cascade of rate-independent hysteresis operators and a dynamical system. However, the inertial dynamics of the structure is not the only contributing factor. A complete model will be complex. Thus, based on the studies done on the phenomenological hysteretic behavior with rate, this paper proposes an adaptive rate-dependent feedforward controller with Prandtl-Ishlinskii (PI) hysteresis operators for piezoelectric actuators. This adaptive controller is achieved by adapting the coefficients to manipulate the weights of the play operators. Actual experiments are conducted to demonstrate the effectiveness of the adaptive controller. The main contribution of this paper is its ability to perform tracking control of non-periodic motion and is illustrated with the tracking control ability of a couple of different non-periodic waveforms which were created by passing random numbers through a low pass filter with a cutoff frequency of 20Hz.

Kalman Orbit Optimized Loop Tracking

Science.gov (United States)

Young, Lawrence E.; Meehan, Thomas K.

2011-01-01

Under certain conditions of low signal power and/or high noise, there is insufficient signal to noise ratio (SNR) to close tracking loops with individual signals on orbiting Global Navigation Satellite System (GNSS) receivers. In addition, the processing power available from flight computers is not great enough to implement a conventional ultra-tight coupling tracking loop. This work provides a method to track GNSS signals at very low SNR without the penalty of requiring very high processor throughput to calculate the loop parameters. The Kalman Orbit-Optimized Loop (KOOL) tracking approach constitutes a filter with a dynamic model and using the aggregate of information from all tracked GNSS signals to close the tracking loop for each signal. For applications where there is not a good dynamic model, such as very low orbits where atmospheric drag models may not be adequate to achieve the required accuracy, aiding from an IMU (inertial measurement unit) or other sensor will be added. The KOOL approach is based on research JPL has done to allow signal recovery from weak and scintillating signals observed during the use of GPS signals for limb sounding of the Earth s atmosphere. That approach uses the onboard PVT (position, velocity, time) solution to generate predictions for the range, range rate, and acceleration of the low-SNR signal. The low- SNR signal data are captured by a directed open loop. KOOL builds on the previous open loop tracking by including feedback and observable generation from the weak-signal channels so that the MSR receiver will continue to track and provide PVT, range, and Doppler data, even when all channels have low SNR.

Tracking of Range and Azimuth for Continuous Imaging of Marine Target in Monopulse ISAR with Wideband Echoes

Directory of Open Access Journals (Sweden)

Junhao Xie

2016-01-01

Full Text Available Real-time tracking of maneuvering targets is the prerequisite for continuous imaging of moving targets in inverse synthetic aperture radar (ISAR. In this paper, the range and azimuth tracking (RAT method with wideband radar echoes is first presented for a mechanical scanning monopulse ISAR, which is regarded as the simplest phased array unit due to the two antenna feeds. To relieve the estimation fluctuation and poor robustness of the RAT method with a single snapshot, a modified range and azimuth tracking approach based on centroid algorithm (RATCA with forgotten factor and multiple echoes is then proposed. The performances of different forgotten factors are investigated. Both theoretical analysis and experimental results demonstrate that RATCA is superior to RAT method. Particularly, when target echo is missing occasionally, RAT method fails while RATCA still keeps good performance. The potential of continuous imaging with shipborne ISAR is verified by experimental results. With minor modification, the method proposed in this paper can be potentially applied in the phased array radar.

A Range-Based Multivariate Model for Exchange Rate Volatility

NARCIS (Netherlands)

B. Tims (Ben); R.J. Mahieu (Ronald)

2003-01-01

textabstractIn this paper we present a parsimonious multivariate model for exchange rate volatilities based on logarithmic high-low ranges of daily exchange rates. The multivariate stochastic volatility model divides the log range of each exchange rate into two independent latent factors, which are

New approach of modeling charged particles track development in CR-39 detectors

International Nuclear Information System (INIS)

Azooz, A.A.; Hermsdorf, D.; Al-Jubbori, M.A.

2013-01-01

In this work, previous modeling of protons and alpha particles track length development in CR-39 solid state nuclear track detectors SSNTD is modified and further extended. The extension involved the accommodation of heavier ions into the model. These ions include deuteron, lithium, boron, carbon, nitrogen and oxygen ions. The new modeling does not contain any case sensitive free fitting parameters. Model calculation results are found to be in good agreement with both experimental data and SRIM software range energy dependence predictions. The access to a single unified and differentiable track length development equation results in the ability to obtain direct results for track etching rates. - Highlights: • New modeling of ions track length evolution measured by different authors. • Ions considered are p, d, α, Li, B, C, N, O. • Equations obtained to describe L(t) and etch rate for all ions at wide energy range. • Equations obtained do not involve any free fitting parameters. • Ions range values obtained compare well with results of SRIM software

5 CFR 534.403 - SES rate range.

Science.gov (United States)

2010-01-01

... first day of the first applicable pay period beginning on or after January 1, 2004, the minimum rate of basic pay of the SES rate range is set at an amount equal to the minimum rate of basic pay under 5 U.S.C... Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PAY UNDER OTHER SYSTEMS Pay and...

The use of long range identification and tracking (LRIT) for modelling the risk of ship-based oil spills

Energy Technology Data Exchange (ETDEWEB)

Szeto, Andrew [Canadian Coast Guard (Canada)], email: andrew.szeto@dfo-mpo.gc.ca; Pelot, Ronald [Dalhousie University (Canada)], email: ronald.pelot@dal.ca

2011-07-01

Accidents involving oil tankers have caused many and sometimes very large oil spills. Such spills to marine areas have a significant impact on environmental quality affecting all aspects of marine ecosystems. Based on valid shipping traffic data as a very important factor that must be considered in modeling the risk of ship-based oil spills, this paper shows the importance of use of the long-range identification and tracking (LRIT) system and looks at how it can be implemented to better assess ship-based oil pollution. The system is a new, accurate and reliable world-wide vessel tracking system with a range of data extended out to 1000 nm from Canadian shores and currently tracks up to about 900 vessels a day in real-time. It is believed that traffic data and effective monitoring can assist with search planning for detection of mystery spills, better resource deployment for spill mitigation, and improving information for research and management.

Measurement of the variable track-etch rate of hydrogen, carbon and oxygen Ions in CR-39

International Nuclear Information System (INIS)

Lengar, I.; Skvarc, J.; Ilic, R.

2003-01-01

The ratio of the track-etch rate to the bulk-etch rate for hydrogen, carbon and oxygen ions was studied for the CR-39 detector with addition of dioctylphthalate. The response was reconstructed from etch-pit growth curves obtained by the multi-step etching technique. A theoretical analysis of the correctness of the method due to the 'missing track segment' is assessed and utilisation of the results obtained for the calibration of fast neutron dosimetry is discussed. (author)

Zadoff-Chu coded ultrasonic signal for accurate range estimation

KAUST Repository

AlSharif, Mohammed H.

2017-11-02

This paper presents a new adaptation of Zadoff-Chu sequences for the purpose of range estimation and movement tracking. The proposed method uses Zadoff-Chu sequences utilizing a wideband ultrasonic signal to estimate the range between two devices with very high accuracy and high update rate. This range estimation method is based on time of flight (TOF) estimation using cyclic cross correlation. The system was experimentally evaluated under different noise levels and multi-user interference scenarios. For a single user, the results show less than 7 mm error for 90% of range estimates in a typical indoor environment. Under the interference from three other users, the 90% error was less than 25 mm. The system provides high estimation update rate allowing accurate tracking of objects moving with high speed.

Zadoff-Chu coded ultrasonic signal for accurate range estimation

KAUST Repository

AlSharif, Mohammed H.; Saad, Mohamed; Siala, Mohamed; Ballal, Tarig; Boujemaa, Hatem; Al-Naffouri, Tareq Y.

2017-01-01

This paper presents a new adaptation of Zadoff-Chu sequences for the purpose of range estimation and movement tracking. The proposed method uses Zadoff-Chu sequences utilizing a wideband ultrasonic signal to estimate the range between two devices with very high accuracy and high update rate. This range estimation method is based on time of flight (TOF) estimation using cyclic cross correlation. The system was experimentally evaluated under different noise levels and multi-user interference scenarios. For a single user, the results show less than 7 mm error for 90% of range estimates in a typical indoor environment. Under the interference from three other users, the 90% error was less than 25 mm. The system provides high estimation update rate allowing accurate tracking of objects moving with high speed.

Using the Moist Static Energy Budget to Understand Storm Track Shifts across a Range of Timescales

Science.gov (United States)

Barpanda, P.; Shaw, T.

2017-12-01

Storm tracks shift meridionally in response to forcing across a range of time scales. Here we formulate a moist static energy (MSE) framework for storm track position and use it to understand storm track shifts in response to seasonal insolation, El Niño minus La Niña conditions, and direct (increased CO2 over land) and indirect (increased sea surface temperature) effects of increased CO2. Two methods (linearized Taylor series and imposed MSE flux divergence) are developed to quantify storm track shifts and decompose them into contributions from net energy (MSE input to the atmosphere minus atmospheric storage) and MSE flux divergence by the mean meridional circulation and stationary eddies. Net energy is not a dominant contribution across the time scales considered. The stationary eddy contribution dominates the storm-track shift in response to seasonal insolation, El Niño minus La Niña conditions, and CO2 direct effect in the Northern Hemisphere, whereas the mean meridional circulation contribution dominates the shift in response to CO2 indirect effect during northern winter and in the Southern Hemisphere during May and October. Overall, the MSE framework shows the seasonal storm-track shift in the Northern Hemisphere is connected to the stationary eddy MSE flux evolution. Furthermore, the equatorward storm-track shift during northern winter in response to El Niño minus La Niña conditions involves a different regime than the poleward shift in response to increased CO2 even though the tropical upper troposphere warms in both cases.

Tracks FAQs: How Do Heart Attack Hospitalization Rates In My Community Compare With Other Counties Or States?

Centers for Disease Control (CDC) Podcasts

In this podcast, CDC Tracking experts discuss how to compare heart attack hospitalization rates in your community with other counties or states. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.

Tracks FAQs: How Can I Tell If Asthma Hospitalization Rates In My Area Are Changing Over Time?

Centers for Disease Control (CDC) Podcasts

In this podcast, CDC Tracking experts discuss asthma hospitalization rates and how you can tell if they've changed in your area over time. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.

Wall-motion tracking in fetal echocardiography-Influence of frame rate on longitudinal strain analysis assessed by two-dimensional speckle tracking.

Science.gov (United States)

Enzensberger, Christian; Achterberg, Friederike; Graupner, Oliver; Wolter, Aline; Herrmann, Johannes; Axt-Fliedner, Roland

2017-06-01

Frame rates (FR) used for strain analysis assessed by speckle tracking in fetal echocardiography show a considerable variation. The aim of this study was to investigate the influence of the FR on strain analysis in 2D speckle tracking. Fetal echocardiography was performed prospectively on a Toshiba Aplio 500 system and a Toshiba Artida system, respectively. Based on an apical or basal four-chamber view of the fetal heart, cine loops were stored with a FR of 30 fps (Aplio 500) and 60 fps (Artida/Aplio 500). For both groups (30fps and 60fps), global and segmental longitudinal peak systolic strain (LPSS) values of both, left (LV) and right ventricle (RV), were assessed by 2D wall-motion tracking. A total of 101 fetuses, distributed to three study groups, were included. The mean gestational age was 25.2±5.0 weeks. Mean global LPSS values for RV in the 30 fps group and in the 60 fps group were -16.07% and -16.47%, respectively. Mean global LPSS values for LV in the 30 fps group and in the 60 fps group were -17.54% and -17.06%, respectively. Comparing global and segmental LPSS values of both, the RV and LV, did not show any statistically significant differences within the two groups. Performance of myocardial 2D strain analysis by wall-motion tracking was feasible with 30 and 60 fps. Obtained global and segmental LPSS values of both ventricles were relatively independent from acquisition rate. © 2017, Wiley Periodicals, Inc.

New progress of ranging technology at Wuhan Satellite Laser Ranging Station

Science.gov (United States)

Xia, Zhiz-Hong; Ye, Wen-Wei; Cai, Qing-Fu

1993-01-01

A satellite laser ranging system with an accuracy of the level of centimeter has been successfully developed at the Institute of Seismology, State Seismological Bureau with the cooperation of the Institute of Geodesy and Geophysics, Chinese Academy of Science. With significant improvements on the base of the second generation SLR system developed in 1985, ranging accuracy of the new system has been upgraded from 15 cm to 3-4 cm. Measuring range has also been expanded, so that the ETALON satellite with an orbit height of 20,000 km launched by the former U.S.S.R. can now be tracked. Compared with the 2nd generation SLR system, the newly developed system has the following improvements. A Q modulated laser is replaced by a mode-locked YAG laser. The new device has a pulse width of 150 ps and a repetition rate of 1-4 pps. A quick response photomultiplier has been adopted as the receiver for echo; for example, the adoption of the MCP tube has obviously reduced the jitter error of the transit time and has improved the ranging accuracy. The whole system is controlled by an IBM PC/XT Computer to guide automatic tracking and measurement. It can carry out these functions for satellite orbit calculation, real-time tracking and adjusting, data acquisition and the preprocessed of observing data, etc. The automatization level and reliability of the observation have obviously improved.

Tracks FAQs: How Can I Tell If Asthma Hospitalization Rates In My Area Are Changing Over Time?

Centers for Disease Control (CDC) Podcasts

2011-06-07

In this podcast, CDC Tracking experts discuss asthma hospitalization rates and how you can tell if they've changed in your area over time. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.  Created: 6/7/2011 by National Center for Environmental Health, Division of Environmental Hazards and Health Effects, Environmental Health Tracking Branch.   Date Released: 6/7/2011.

Tracks FAQs: How Do Heart Attack Hospitalization Rates In My Community Compare With Other Counties Or States?

Centers for Disease Control (CDC) Podcasts

2011-09-01

In this podcast, CDC Tracking experts discuss how to compare heart attack hospitalization rates in your community with other counties or states. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.  Created: 9/1/2011 by National Center for Environmental Health, Division of Environmental Hazards and Health Effects, Environmental Health Tracking Branch.   Date Released: 9/1/2011.

Readmission rates after a planned hospital stay of 2 versus 3 days in fast-track colonic surgery

DEFF Research Database (Denmark)

Andersen, Jens; Hjort-Jakobsen, Dorthe; Christiansen, P. S.

2007-01-01

BACKGROUND: Initial programmes of fast-track open colonic surgery with a planned 2-day postoperative hospital stay have had a high readmission rate (about 20 per cent). The aim of this large, consecutive series was to compare readmission rates after a fast-track open colonic surgery programme....... There was no difference in type and incidence of morbidity between the two periods. CONCLUSION: Readmission after fast-track open colonic resection was reduced by planning discharge 3 instead of 2 days after surgery, with the same discharge criteria. Copyright (c) 2007 British Journal of Surgery Society Ltd. Published...... from August 2004. All patients were examined 8 and 30 days after surgery. RESULTS: Readmission rates fell from 20.1 per cent in 408 patients with a planned 2-day hospital stay (period 1) to 11.3 per cent in 133 patients with a planned 3-day hospital stay (period 2) (P

A comparative study of track registration response of Makrofol-(KG, KL and N) polycarbonate to sup 4 sup 0 Ar ions

CERN Document Server

Kumar, A

1999-01-01

In the present work a comparative study of track registration response of sup 4 sup 0 Ar ions in different types of Makrofol polycarbonates viz. Makrofol-KG, KL and N have been done. The etched track parameters viz. bulk etch rate, track etch rate, etch rate ratio, cone angle and etching efficiency were calculated. The variation of etching rates with temperature were found to be exponential and follow the Arrhenius equation. The values of activation energy for bulk and track etching were also calculated. Maximum etchable track length/range were also obtained and compared with the theoretical values obtained from computer program RANGE. From the results it is found that the polycarbonates having same chemical composition manufactured by different chemical processes have slightly different behavior

A Range-Based Multivariate Model for Exchange Rate Volatility

OpenAIRE

Tims, Ben; Mahieu, Ronald

2003-01-01

textabstractIn this paper we present a parsimonious multivariate model for exchange rate volatilities based on logarithmic high-low ranges of daily exchange rates. The multivariate stochastic volatility model divides the log range of each exchange rate into two independent latent factors, which are interpreted as the underlying currency specific components. Due to the normality of logarithmic volatilities the model can be estimated conveniently with standard Kalman filter techniques. Our resu...

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

Science.gov (United States)

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

2017-05-01

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

Signature of biased range in the non-dynamical Chern-Simons modified gravity and its measurements with satellite-satellite tracking missions: theoretical studies

Science.gov (United States)

Qiang, Li-E.; Xu, Peng

2015-08-01

Having great accuracy in the range and range rate measurements, the GRACE mission and the planed GRACE follow on mission can in principle be employed to place strong constraints on certain relativistic gravitational theories. In this paper, we work out the range observable of the non-dynamical Chern-Simons modified gravity for the satellite-to-satellite tracking (SST) measurements. We find out that a characteristic time accumulating range signal appears in non-dynamical Chern-Simons gravity, which has no analogue found in the standard parity-preserving metric theories of gravity. The magnitude of this Chern-Simons range signal will reach a few times of cm for each free flight of these SST missions, here is the dimensionless post-Newtonian parameter of the non-dynamical Chern-Simons theory. Therefore, with the 12 years data of the GRACE mission, one expects that the mass scale of the non-dynamical Chern-Simons gravity could be constrained to be larger than eV. For the GRACE FO mission that scheduled to be launched in 2017, the much stronger bound that eV is expected.

CR-39 track detector for multi-MeV ion spectroscopy.

Science.gov (United States)

Jeong, T W; Singh, P K; Scullion, C; Ahmed, H; Hadjisolomou, P; Jeon, C; Yun, H; Kakolee, K F; Borghesi, M; Ter-Avetisyan, S

2017-05-19

We present the characteristics of track formation on the front and rear surfaces of CR-39 produced by laser-driven protons and carbon ions. A methodological approach, based on bulk etch length, is proposed to uniquely characterize the particle tracks in CR-39, enabling comparative description of the track characteristics in different experiments. The response of CR-39 to ions is studied based on the energy dependent growth rate of the track diameter to understand the intrinsic particle stopping process within the material. A large non-uniformity in the track diameter is observed for CR-39 with thickness matching with the stopping range of particles. Simulation and experimental results show the imprint of longitudinal range straggling for energetic protons. Moreover, by exploiting the energy dependence of the track diameter, the energy resolution (δE/E) of CR-39 for few MeV protons and Carbon ion is found to be about 3%.

Video-rate or high-precision: a flexible range imaging camera

Science.gov (United States)

Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.; Payne, Andrew D.; Conroy, Richard M.; Godbaz, John P.; Jongenelen, Adrian P. P.

2008-02-01

A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a relatively high resolution (512-by-512) pixels and high precision (0.4 mm best case) configuration, but with a slow measurement rate (one every 10 s). Although this high precision range imaging is useful for some applications, the low acquisition speed is limiting in many situations. The system's frame rate and length of acquisition is fully configurable in software, which means the measurement rate can be increased by compromising precision and image resolution. In this paper we demonstrate the flexibility of our range imaging system by showing examples of high precision ranging at slow acquisition speeds and video-rate ranging with reduced ranging precision and image resolution. We also show that the heterodyne approach and the use of more than four samples per beat cycle provides better linearity than the traditional homodyne quadrature detection approach. Finally, we comment on practical issues of frame rate and beat signal frequency selection.

Incorporation of a laser range scanner into image-guided liver surgery: Surface acquisition, registration, and tracking

International Nuclear Information System (INIS)

Cash, David M.; Sinha, Tuhin K.; Chapman, William C.; Terawaki, Hiromi; Dawant, Benoit M.; Galloway, Robert L.; Miga, Michael I.

2003-01-01

As image guided surgical procedures become increasingly diverse, there will be more scenarios where point-based fiducials cannot be accurately localized for registration and rigid body assumptions no longer hold. As a result, procedures will rely more frequently on anatomical surfaces for the basis of image alignment and will require intraoperative geometric data to measure and compensate for tissue deformation in the organ. In this paper we outline methods for which a laser range scanner may be used to accomplish these tasks intraoperatively. A laser range scanner based on the optical principle of triangulation acquires a dense set of three-dimensional point data in a very rapid, noncontact fashion. Phantom studies were performed to test the ability to link range scan data with traditional modes of image-guided surgery data through localization, registration, and tracking in physical space. The experiments demonstrate that the scanner is capable of localizing point-based fiducials to within 0.2 mm and capable of achieving point and surface based registrations with target registration error of less than 2.0 mm. Tracking points in physical space with the range scanning system yields an error of 1.4±0.8 mm. Surface deformation studies were performed with the range scanner in order to determine if this device was capable of acquiring enough information for compensation algorithms. In the surface deformation studies, the range scanner was able to detect changes in surface shape due to deformation comparable to those detected by tomographic image studies. Use of the range scanner has been approved for clinical trials, and an initial intraoperative range scan experiment is presented. In all of these studies, the primary source of error in range scan data is deterministically related to the position and orientation of the surface within the scanner's field of view. However, this systematic error can be corrected, allowing the range scanner to provide a rapid, robust

Acquisition and tracking for underwater optical communications

Science.gov (United States)

Williams, Andrew J.; Laycock, Leslie L.; Griffith, Michael S.; McCarthy, Andrew G.; Rowe, Duncan P.

2017-10-01

There is a growing requirement to transfer large volumes of data between underwater platforms. As seawater is transmissive in the visible band, underwater optical communications is an active area of interest since it offers the potential for power efficient, covert and high bandwidth datalinks at short to medium ranges. Short range systems have been successfully demonstrated using sources with low directionality. To realise higher data rates and/or longer ranges, the use of more efficient directional beams is required; by necessity, these must be sufficiently aligned to achieve the required link margin. For mobile platforms, the acquisition and tracking of each node is therefore critical in order to establish and maintain an optical datalink. This paper describes work undertaken to demonstrate acquisition and tracking in a 3D underwater environment. A range of optical sources, beam steering technologies, and tracking sensors have been assessed for suitability. A novel scanning strategy exploiting variable beam divergence was developed to provide robust acquisition whilst minimising acquisition time. A prototype system was assembled and demonstrated in a large water tank. This utilised custom quadrant detectors based on Silicon PhotoMultiplier (SiPM) arrays for fine tracking, and a Wide Field of View (WFoV) sCMOS camera for link acquisition. Fluidic lenses provided dynamic control of beam divergence, and AC modulation/filtering enabled background rejection. The system successfully demonstrated robust optical acquisition and tracking between two nodes with only nanowatt received optical powers. The acquisition time was shown to be dependent on the initial conditions and the transmitted optical power.

Study of uranium mineralization in rock samples from marwat range bannu basin by fission track analysis technique

International Nuclear Information System (INIS)

Qureshi, A.Z.; Ullah, K.; Ullah, N.; Akram, M.

2004-07-01

The Geophysics Division, Atomic Energy Minerals Centre (AEMC), Lahore has planned a uranium exploration program in Marwat Range, Bannu Basin. In this connection 30 thin sections of rock samples, collected from four areas; namely, Darra Tang, Simukili, Karkanwal and Sheikhillah from Marwat Range, and one from Salt Range were provided to Nuclear Geology Group of Physics Research Division, PINSTECH for the study of nature and mechanism of uranium mineralization These studies are aimed to help in designing uranium exploration strategy by providing the loci of uranium sources in the Marwat and Salt Ranges. The samples have been studied using fission track analysis technique. (author)

Multi-UAV Doppler Information Fusion for Target Tracking Based on Distributed High Degrees Information Filters

Directory of Open Access Journals (Sweden)

Hamza Benzerrouk

2018-03-01

Full Text Available Multi-Unmanned Aerial Vehicle (UAV Doppler-based target tracking has not been widely investigated, specifically when using modern nonlinear information filters. A high-degree Gauss–Hermite information filter, as well as a seventh-degree cubature information filter (CIF, is developed to improve the fifth-degree and third-degree CIFs proposed in the most recent related literature. These algorithms are applied to maneuvering target tracking based on Radar Doppler range/range rate signals. To achieve this purpose, different measurement models such as range-only, range rate, and bearing-only tracking are used in the simulations. In this paper, the mobile sensor target tracking problem is addressed and solved by a higher-degree class of quadrature information filters (HQIFs. A centralized fusion architecture based on distributed information filtering is proposed, and yielded excellent results. Three high dynamic UAVs are simulated with synchronized Doppler measurement broadcasted in parallel channels to the control center for global information fusion. Interesting results are obtained, with the superiority of certain classes of higher-degree quadrature information filters.

Movement Patterns, Home Range Size and Habitat Selection of an Endangered Resource Tracking Species, the Black-Throated Finch (Poephila cincta cincta).

Science.gov (United States)

Rechetelo, Juliana; Grice, Anthony; Reside, April Elizabeth; Hardesty, Britta Denise; Moloney, James

2016-01-01

Understanding movement patterns and home range of species is paramount in ecology; it is particularly important for threatened taxa as it can provide valuable information for conservation management. To address this knowledge gap for a range-restricted endangered bird, we estimated home range size, daily movement patterns and habitat use of a granivorous subspecies in northeast Australia, the black-throated finch (Poephila cincta cincta; BTF) using radio-tracking and re-sighting of colour banded birds. Little is known about basic aspects of its ecology including movement patterns and home range sizes. From 2011-2014 we colour-banded 102 BTF and radio-tracked 15 birds. We generated home ranges (calculated using kernel and Minimum Convex Polygons techniques of the 15 tracked BTF). More than 50% of the re-sightings occurred within 200 m of the banding site (n = 51 out of 93 events) and within 100 days of capture. Mean home-range estimates with kernel (50%, 95% probability) and Minimum Convex Polygons were 10.59 ha, 50.79 ha and 46.27 ha, respectively. Home range size differed between two capture sites but no seasonal differences were observed. BTF home ranges overlapped four habitat types among eight available. Habitat selection was different from random at Site 1 (χ2 = 373.41, df = 42, pmovements may be related to resource bottleneck periods. Daily movement patterns differed between sites, which is likely linked to the fact that the sites differ in the spatial distribution of resources. The work provides information about home range sizes and local movement of BTF that will be valuable for targeting effective management and conservation strategies for this endangered granivore.

Tonopah Test Range - Index

Science.gov (United States)

Capabilities Test Operations Center Test Director Range Control Track Control Communications Tracking Radars Photos Header Facebook Twitter YouTube Flickr RSS Tonopah Test Range Top TTR_TOC Tonopah is the testing range of choice for all national security missions. Tonopah Test Range (TTR) provides research and

Solar tracking system

Science.gov (United States)

White, P. R.; Scott, D. R. (Inventor)

1981-01-01

A solar tracker for a solar collector is described in detail. The collector is angularly oriented by a motor wherein the outputs of two side-by-side photodetectors are discriminated as to three ranges: a first corresponding to a low light or darkness condition; a second corresponding to light intensity lying in an intermediate range; and a third corresponding to light above an intermediate range, direct sunlight. The first output drives the motor to a selected maximum easterly angular position; the second enables the motor to be driven westerly at the Earth rotational rate; and the third output, the separate outputs of the two photodetectors, differentially controls the direction of rotation of the motor to effect actual tracking of the Sun.

Four-dimensional dose distributions of step-and-shoot IMRT delivered with real-time tumor tracking for patients with irregular breathing: Constant dose rate vs dose rate regulation

International Nuclear Information System (INIS)

Yang Xiaocheng; Han-Oh, Sarah; Gui Minzhi; Niu Ying; Yu, Cedric X.; Yi Byongyong

2012-01-01

Purpose: Dose-rate-regulated tracking (DRRT) is a tumor tracking strategy that programs the MLC to track the tumor under regular breathing and adapts to breathing irregularities during delivery using dose rate regulation. Constant-dose-rate tracking (CDRT) is a strategy that dynamically repositions the beam to account for intrafractional 3D target motion according to real-time information of target location obtained from an independent position monitoring system. The purpose of this study is to illustrate the differences in the effectiveness and delivery accuracy between these two tracking methods in the presence of breathing irregularities. Methods: Step-and-shoot IMRT plans optimized at a reference phase were extended to remaining phases to generate 10-phased 4D-IMRT plans using segment aperture morphing (SAM) algorithm, where both tumor displacement and deformation were considered. A SAM-based 4D plan has been demonstrated to provide better plan quality than plans not considering target deformation. However, delivering such a plan requires preprogramming of the MLC aperture sequence. Deliveries of the 4D plans using DRRT and CDRT tracking approaches were simulated assuming the breathing period is either shorter or longer than the planning day, for 4 IMRT cases: two lung and two pancreatic cases with maximum GTV centroid motion greater than 1 cm were selected. In DRRT, dose rate was regulated to speed up or slow down delivery as needed such that each planned segment is delivered at the planned breathing phase. In CDRT, MLC is separately controlled to follow the tumor motion, but dose rate was kept constant. In addition to breathing period change, effect of breathing amplitude variation on target and critical tissue dose distribution is also evaluated. Results: Delivery of preprogrammed 4D plans by the CDRT method resulted in an average of 5% increase in target dose and noticeable increase in organs at risk (OAR) dose when patient breathing is either 10% faster or

Large angle tracking and high discriminating tracking in nuclear emulsion

International Nuclear Information System (INIS)

Matsuo, Tomokazu; Shibuya, Hiroshi; Ogawa, Satoru; Fukuda, Tsutomu; Mikado, Shoji

2015-01-01

Nuclear emulsion is a high resolution and re-analyzable detector. Conventional “Track Selector” which have angle acceptance |tan θ|<0.6 are widely used to find tracks in emulsion. We made a new track selector “Fine Track Selector” (FTS) which has large angle acceptance and high discriminating ability. The FTS reduces fake tracks using new algorithms, navigation etc. FTS also keeps finding efficiency of tracks around 90% in an angle range of |tan θ| < 3.5. FTS was applied to the τ candidate in OPERA and no additional tracks found. FTS will be useful to our new J-PARC emulsion experiment.

Plastic nuclear track detectors as high x-ray and gamma dosimeters

International Nuclear Information System (INIS)

Chong Chon Sing

1995-01-01

A brief review of recent studies on the effects of high doses of x-ray and gamma ray on the track registration properties of several plastic track detectors is presented. The bulk etching rates and the etched track sizes have been found to increase with the dose in the range up to 100 Mrad. These results suggest that the changes in track registration characteristics can be employed as an index of the radiation dose in the megarad region. In particular, recent results on the effect of X-ray irradiation on two types of cellulose nitrate track detectors obtained in our laboratory are reported in this paper. (author)

Monopole track characteristics in plastic detectors

Science.gov (United States)

Ahlen, S. P.

1975-01-01

Total and restricted energy loss rates were calculated for magnetic monopoles of charge g = 137 e in Lexan polycarbonate. Range-energy curves are also presented. The restricted energy loss model is used to estimate the appearance of a monopole track in plastic detectors. These results should be useful for the design and analysis of monopole experiments.

A simulation of the Four-way lunar Lander-Orbiter tracking mode for the Chang'E-5 mission

Science.gov (United States)

Li, Fei; Ye, Mao; Yan, Jianguo; Hao, Weifeng; Barriot, Jean-Pierre

2016-06-01

The Chang'E-5 mission is the third phase of the Chinese Lunar Exploration Program and will collect and return lunar samples. After sampling, the Orbiter and the ascent vehicle will rendezvous and dock, and both spacecraft will require high precision orbit navigation. In this paper, we present a novel tracking mode-Four-way lunar Lander-Orbiter tracking that possibly can be employed during the Chang'E-5 mission. The mathematical formulas for the Four-way lunar Lander-Orbiter tracking mode are given and implemented in our newly-designed lunar spacecraft orbit determination and gravity field recovery software, the LUnar Gravity REcovery and Analysis Software/System (LUGREAS). The simulated observables permit analysis of the potential contribution Four-way lunar Lander-Orbiter tracking could make to precision orbit determination for the Orbiter. Our results show that the Four-way lunar Lander-Orbiter Range Rate has better geometric constraint on the orbit, and is more sensitive than the traditional two-way range rate that only tracks data between the Earth station and lunar Orbiter. After combining the Four-way lunar Lander-Orbiter Range Rate data with the traditional two-way range rate data and considering the Lander position error and lunar gravity field error, the accuracy of precision orbit determination for the Orbiter in the simulation was improved significantly, with the biggest improvement being one order of magnitude, and the Lander position could be constrained to sub-meter level. This new tracking mode could provide a reference for the Chang'E-5 mission and have enormous potential for the positioning of future lunar farside Lander due to its relay characteristic.

Solid state nuclear track detectors

International Nuclear Information System (INIS)

Medeiros, J.A.; Carvalho, M.L.C.P. de

1992-12-01

Solid state nuclear track detectors (SSNTD) are dielectric materials, crystalline or vitreous, which registers tracks of charged nuclear particles, like alpha particles or fission fragments. Chemical etching of the detectors origin tracks that are visible at the optical microscope: track etching rate is higher along the latent track, where damage due to the charged particle increase the chemical potential, and etching rate giving rise to holes, the etched tracks. Fundamental principles are presented as well as some ideas of main applications. (author)

Diversification Rates and the Evolution of Species Range Size Frequency Distribution

Directory of Open Access Journals (Sweden)

Silvia Castiglione

2017-11-01

Full Text Available The geographic range sizes frequency distribution (RFD within clades is typically right-skewed with untransformed data, and bell-shaped or slightly left-skewed under the log-transformation. This means that most species within clades occupy diminutive ranges, whereas just a few species are truly widespread. A number of ecological and evolutionary explanations have been proposed to account for this pattern. Among the latter, much attention has been given to the issue of how extinction and speciation probabilities influence RFD. Numerous accounts now convincingly demonstrate that extinction rate decreases with range size, both in living and extinct taxa. The relationship between range size and speciation rate, though, is much less obvious, with either small or large ranged species being proposed to originate more daughter taxa. Herein, we used a large fossil database including 21 animal clades and more than 80,000 fossil occurrences distributed over more than 400 million years of marine metazoans (exclusive of vertebrates evolution, to test the relationship between extinction rate, speciation rate, and range size. As expected, we found that extinction rate almost linearly decreases with range size. In contrast, speciation rate peaks at the large (but not the largest end of the range size spectrum. This is consistent with the peripheral isolation mode of allopatric speciation being the main mechanism of species origination. The huge variation in phylogeny, fossilization potential, time of fossilization, and the overarching effect of mass extinctions suggest caution must be posed at generalizing our results, as individual clades may deviate significantly from the general pattern.

Science and technology with nuclear tracks in solids

CERN Document Server

Buford-Price, P

2005-01-01

Fission track dating has greatly expanded its usefulness to geology over the last 40 years. It is central to thermochronology—the use of shortened fission tracks to decipher the thermal history, movement, and provenance of rocks. When combined with other indicators, such as zircon color and (U–Th)/He, a range of temperatures from C to C can be studied. Combining fission track analysis with cosmogenic nuclide decay rates, one can study landscape development and denudation of passive margins. Technological applications have expanded from biological filters, radon mapping, and dosimetry to the use of ion track microtechnology in microlithography, micromachining by ion track etching, microscopic field emission tips, magnetic nanowires as magnetoresistive sensors, microfluidic devices, physiology of ion channels in single cells, and so on. In nuclear and particle physics, relatively insensitive glass detectors have been almost single-handedly responsible for our knowledge of cluster radioactivity, and plastic ...

[Laparoscopic "fast-track" sigmoidectomy for diverticulitis disease in Germany. Results of a prospective quality assurance program].

Science.gov (United States)

Tsilimparis, N; Haase, O; Wendling, P; Kipfmüller, K; Schmid, M; Engemann, R; Schwenk, W

2010-09-01

The natural course of sigmoid colon diverticulitis during conservative therapy and the assessment of the perioperative morbidity after sigmoid colon resection are differently evaluated by surgeons and gastroenterologists. The "fast-track" rehabilitation accelerates the reconvalescence and reduces the rate of postoperative general complications after colorectal surgery. The results of the laparoscopic "Fast-track" sigmoidectomy should be examined within a quality assurance program to better evaluate the perioperative risks following surgical management of diverticulitis. A prospective data collection within the voluntary quality assurance program "fast-track" Kolon II was performed. All participating clinics agreed on a multimodal, evidence-based standard perioperative treatment in terms of a "fast-track" rehabilitation for elective operations for sigmoid diverticulitis. Data from 846 patients undergoing laparoscopic "fast-track" sigmoid colon resection in 23 surgical departments in Germany were collected and evaluated. The mean age of the patients was 63 years (range 23 - 91). 203 patients (24 %) had severe co-morbidities (ASA classification III - IV). A conversion to conventional open surgery was necessary in 51 cases (6 %). Complications occurred in 93 patients (11 %). 76 patients suffered a surgical complication (8.9 %) and 32 patients (3.8 %) a general complication. Two patients died postoperatively due to multi-organ failure following anastomotic leaks. The patients took solid food in median on day 1 after surgery (range, 0 - 5) and passed stool on day 2 (range, 0 - 22). Predefined discharge criteria (free of pain on oral medication, normal oral feeding, stool) were met on day 4 (range, 1 - 58) and the patients were discharged on day 7 (range, 3 - 72). The 30-day re-admission rate was 3.9 %. Patients undergoing laparoscopic "fast-track" sigmoidectomy had a low rate of general complications and had a rapid reconvalescence with a short postoperative in

Proton tracking in a high-granularity Digital Tracking Calorimeter for proton CT purposes

Science.gov (United States)

Pettersen, H. E. S.; Alme, J.; Biegun, A.; van den Brink, A.; Chaar, M.; Fehlker, D.; Meric, I.; Odland, O. H.; Peitzmann, T.; Rocco, E.; Ullaland, K.; Wang, H.; Yang, S.; Zhang, C.; Röhrich, D.

2017-07-01

Radiation therapy with protons as of today utilizes information from x-ray CT in order to estimate the proton stopping power of the traversed tissue in a patient. The conversion from x-ray attenuation to proton stopping power in tissue introduces range uncertainties of the order of 2-3% of the range, uncertainties that are contributing to an increase of the necessary planning margins added to the target volume in a patient. Imaging methods and modalities, such as Dual Energy CT and proton CT, have come into consideration in the pursuit of obtaining an as good as possible estimate of the proton stopping power. In this study, a Digital Tracking Calorimeter is benchmarked for proof-of-concept for proton CT purposes. The Digital Tracking Calorimeter was originally designed for the reconstruction of high-energy electromagnetic showers for the ALICE-FoCal project. The presented prototype forms the basis for a proton CT system using a single technology for tracking and calorimetry. This advantage simplifies the setup and reduces the cost of a proton CT system assembly, and it is a unique feature of the Digital Tracking Calorimeter concept. Data from the AGORFIRM beamline at KVI-CART in Groningen in the Netherlands and Monte Carlo simulation results are used to in order to develop a tracking algorithm for the estimation of the residual ranges of a high number of concurrent proton tracks. High energy protons traversing the detector leave a track through the sensor layers. These tracks are spread out through charge diffusion processes. A charge diffusion model is applied for acquisition of estimates of the deposited energy of the protons in each sensor layer by using the size of the charge diffused area. A model fit of the Bragg Curve is applied to each reconstructed track and through this, estimating the residual range of each proton. The range of the individual protons can at present be estimated with a resolution of 4%. The readout system for this prototype is able to

Proton tracking in a high-granularity Digital Tracking Calorimeter for proton CT purposes

Energy Technology Data Exchange (ETDEWEB)

Pettersen, H.E.S., E-mail: helge.pettersen@helse-bergen.no [Department of Oncology and Medical Physics, Haukeland University Hospital, Postbox 1400, 5021 Bergen (Norway); Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway); Alme, J. [Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway); Biegun, A. [Kernfysisch Versneller Instituut, University of Groningen, NL-9747 AA Groningen (Netherlands); Brink, A. van den [Nikhef, Utrecht University, Postbox 41882, 1009 DB Amsterdam (Netherlands); Chaar, M.; Fehlker, D. [Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway); Meric, I. [Department of Electrical Engineering, Bergen University College, Postbox 7030, 5020 Bergen (Norway); Odland, O.H. [Department of Oncology and Medical Physics, Haukeland University Hospital, Postbox 1400, 5021 Bergen (Norway); Peitzmann, T.; Rocco, E. [Nikhef, Utrecht University, Postbox 41882, 1009 DB Amsterdam (Netherlands); Ullaland, K. [Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway); Wang, H. [Nikhef, Utrecht University, Postbox 41882, 1009 DB Amsterdam (Netherlands); Yang, S. [Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway); Zhang, C. [Nikhef, Utrecht University, Postbox 41882, 1009 DB Amsterdam (Netherlands); Röhrich, D. [Department of Physics and Technology, University of Bergen, Postbox 7803, 5020 Bergen (Norway)

2017-07-11

Radiation therapy with protons as of today utilizes information from x-ray CT in order to estimate the proton stopping power of the traversed tissue in a patient. The conversion from x-ray attenuation to proton stopping power in tissue introduces range uncertainties of the order of 2–3% of the range, uncertainties that are contributing to an increase of the necessary planning margins added to the target volume in a patient. Imaging methods and modalities, such as Dual Energy CT and proton CT, have come into consideration in the pursuit of obtaining an as good as possible estimate of the proton stopping power. In this study, a Digital Tracking Calorimeter is benchmarked for proof-of-concept for proton CT purposes. The Digital Tracking Calorimeter was originally designed for the reconstruction of high-energy electromagnetic showers for the ALICE-FoCal project. The presented prototype forms the basis for a proton CT system using a single technology for tracking and calorimetry. This advantage simplifies the setup and reduces the cost of a proton CT system assembly, and it is a unique feature of the Digital Tracking Calorimeter concept. Data from the AGORFIRM beamline at KVI-CART in Groningen in the Netherlands and Monte Carlo simulation results are used to in order to develop a tracking algorithm for the estimation of the residual ranges of a high number of concurrent proton tracks. High energy protons traversing the detector leave a track through the sensor layers. These tracks are spread out through charge diffusion processes. A charge diffusion model is applied for acquisition of estimates of the deposited energy of the protons in each sensor layer by using the size of the charge diffused area. A model fit of the Bragg Curve is applied to each reconstructed track and through this, estimating the residual range of each proton. The range of the individual protons can at present be estimated with a resolution of 4%. The readout system for this prototype is able to

Readmission rates after a planned hospital stay of 2 versus 3 days in fast-track colonic surgery

DEFF Research Database (Denmark)

Andersen, Jens; Hjort-Jakobsen, Dorthe; Christiansen, P. S.

2007-01-01

BACKGROUND: Initial programmes of fast-track open colonic surgery with a planned 2-day postoperative hospital stay have had a high readmission rate (about 20 per cent). The aim of this large, consecutive series was to compare readmission rates after a fast-track open colonic surgery programme...... from August 2004. All patients were examined 8 and 30 days after surgery. RESULTS: Readmission rates fell from 20.1 per cent in 408 patients with a planned 2-day hospital stay (period 1) to 11.3 per cent in 133 patients with a planned 3-day hospital stay (period 2) (P ... hospital stay was 2 and 3 days, median stay after readmission was 5 and 5.5 days, and median (mean) total stay was 3 (5.6) and 3 (5.7) days in periods 1 and 2 respectively. The readmission rate in period 2 was lower because there were fewer readmissions for short-term observation or social reasons...

Laser technology for high precision satellite tracking

Science.gov (United States)

Plotkin, H. H.

1974-01-01

Fixed and mobile laser ranging stations have been developed to track satellites equipped with retro-reflector arrays. These have operated consistently at data rates of once per second with range precision better than 50 cm, using Q-switched ruby lasers with pulse durations of 20 to 40 nanoseconds. Improvements are being incorporated to improve the precision to 10 cm, and to permit ranging to more distant satellites. These include improved reflector array designs, processing and analysis of the received reflection pulses, and use of sub-nanosecond pulse duration lasers.

Effect of various etching conditions on the response of Cr-39 plastic track detector applied for radon dosimetry in environment

International Nuclear Information System (INIS)

Maged, A.F.; Ashraf, F.A.

1997-01-01

A solid state nuclear track detector Cr-39 has been used for measuring the radon concentration in the soil air and indoor concentration. The bulk etch rate, C B of Cr-39 has been measured in various concentrations of NaOH in the range (6-8 mole) at temperature 70 degree C. In addition, the track etch rate, V T , and the ratio V = V T /V B , of alpha particles emitted from radon gas exists in nature have been measured in a similar range of etching conditions. This study shows that 8 M NaOH at 70 degree C represent the optimum etching conditions for Cr-39, with the range of the present study. The equilibrium factor and gamma-dose equivalent were calculated by using the track densities of open and filtered solid state nuclear track detectors

A Tracking Analyst for large 3D spatiotemporal data from multiple sources (case study: Tracking volcanic eruptions in the atmosphere)

Science.gov (United States)

Gad, Mohamed A.; Elshehaly, Mai H.; Gračanin, Denis; Elmongui, Hicham G.

2018-02-01

This research presents a novel Trajectory-based Tracking Analyst (TTA) that can track and link spatiotemporally variable data from multiple sources. The proposed technique uses trajectory information to determine the positions of time-enabled and spatially variable scatter data at any given time through a combination of along trajectory adjustment and spatial interpolation. The TTA is applied in this research to track large spatiotemporal data of volcanic eruptions (acquired using multi-sensors) in the unsteady flow field of the atmosphere. The TTA enables tracking injections into the atmospheric flow field, the reconstruction of the spatiotemporally variable data at any desired time, and the spatiotemporal join of attribute data from multiple sources. In addition, we were able to create a smooth animation of the volcanic ash plume at interactive rates. The initial results indicate that the TTA can be applied to a wide range of multiple-source data.

Modifications of radiation detection response of PADC track detectors by photons

CERN Document Server

Sinha, D

1998-01-01

Photon induced modifications in polyalyldiglycol carbonate (PADC) track detectors have been studied in the dose range of 10 sup 1 -10 sup 6 Gy. It was found that some of the properties like bulk-etch rate, track-etch rate got enhanced at the dose of 10 sup 6 Gy. Activation energy for bulk-etching has been determined for different gamma doses. In order to correlate the high etch rate with the chemical modifications, UV-Vis, IR and ESR studies were carried out. These studies clearly give the indication that radiation damage results into radical formation through bond cleavage. TGA study was performed for understanding the thermal resistance of this detector. The results are presented and discussed.

The impact of leaf width and plan complexity on DMLC tracking of prostate intensity modulated arc therapy

DEFF Research Database (Denmark)

Pommer, Tobias; Falk, Marianne; Poulsen, Per Rugaard

2013-01-01

Purpose: Intensity modulated arc therapy (IMAT) is commonly used to treat prostate cancer. The purpose of this study was to evaluate the impact of leaf width and plan complexity on dynamic multileaf collimator (DMLC) tracking for prostate motion management during IMAT treatments.Methods: Prostate...... IMAT plans were delivered with either a high-definition MLC (HDMLC) or a Millennium MLC (M-MLC) (0.25 and 0.50 cm central leaf width, respectively), with and without DMLC tracking, to a dosimetric phantom that reproduced four prostate motion traces. The plan complexity was varied by applying leaf....... The corresponding pass rates without tracking were 87.6% (range 76.2%-94.7%) and 91.1% (range 81.4%-97.6%), respectively. Decreased plan complexity improved the pass rate when static target measurements were used as reference, but not with the planned dose as reference. The main cause of tracking errors was leaf...

Single track coincidence measurements of fluorescent and plastic nuclear track detectors in therapeutic carbon beams

International Nuclear Information System (INIS)

Osinga, J-M; Jäkel, O; Ambrožová, I; Brabcová, K Pachnerová; Davídková, M; Akselrod, M S; Greilich, S

2014-01-01

In this paper we present a method for single track coincidence measurements using two different track detector materials. We employed plastic and fluorescent nuclear track detectors (PNTDs and FNTDs) in the entrance channel of a monoenergetic carbon ion beam covering the therapeutic energy range from 80 to 425 MeV/u. About 99% of all primary particle tracks detected by both detectors were successfully matched, while 1% of the particles were only detected by the FNTDs because of their superior spatial resolution. We conclude that both PNTDs and FNTDs are suitable for clinical carbon beam dosimetry with a detection efficiency of at least 98.82% and 99.83% respectively, if irradiations are performed with low fluence in the entrance channel of the ion beam. The investigated method can be adapted to other nuclear track detectors and offers the possibility to characterize new track detector materials against well-known detectors. Further, by combining two detectors with a restricted working range in the presented way a hybrid-detector system can be created with an extended and optimized working range

A quantum inspired model of radar range and range-rate measurements with applications to weak value measurements

Science.gov (United States)

Escalante, George

2017-05-01

Weak Value Measurements (WVMs) with pre- and post-selected quantum mechanical ensembles were proposed by Aharonov, Albert, and Vaidman in 1988 and have found numerous applications in both theoretical and applied physics. In the field of precision metrology, WVM techniques have been demonstrated and proven valuable as a means to shift, amplify, and detect signals and to make precise measurements of small effects in both quantum and classical systems, including: particle spin, the Spin-Hall effect of light, optical beam deflections, frequency shifts, field gradients, and many others. In principal, WVM amplification techniques are also possible in radar and could be a valuable tool for precision measurements. However, relatively limited research has been done in this area. This article presents a quantum-inspired model of radar range and range-rate measurements of arbitrary strength, including standard and pre- and post-selected measurements. The model is used to extend WVM amplification theory to radar, with the receive filter performing the post-selection role. It is shown that the description of range and range-rate measurements based on the quantum-mechanical measurement model and formalism produces the same results as the conventional approach used in radar based on signal processing and filtering of the reflected signal at the radar receiver. Numerical simulation results using simple point scatterrer configurations are presented, applying the quantum-inspired model of radar range and range-rate measurements that occur in the weak measurement regime. Potential applications and benefits of the quantum inspired approach to radar measurements are presented, including improved range and Doppler measurement resolution.

Testing for long-range dependence in the Brazilian term structure of interest rates

International Nuclear Information System (INIS)

Cajueiro, Daniel O.; Tabak, Benjamin M.

2009-01-01

This paper presents empirical evidence of fractional dynamics in interest rates for different maturities for Brazil. A variation of a newly developed test for long-range dependence, the V/S statistic, with a post-blackening bootstrap is employed. Results suggest that Brazilian interest rates possess strong long-range dependence in volatility, even when considering the structural break in 1999. These findings imply that the development of policy models that give rise to long-range dependence in interest rates' volatility could be very useful. The long-short-term interest rates spread has strong long-range dependence, which suggests that traditional tests of expectation hypothesis of the term structure of interest rates may be misspecified.

Home Range and Habitat Use of the New Zealand Falcon (Falco novaeseelandiae within a Plantation Forest: A Satellite Tracking Study

Directory of Open Access Journals (Sweden)

Bindi Thomas

2010-01-01

Full Text Available We tracked two adult and three juvenile New Zealand falcons (Falco novaeseelandiae in Kaingaroa Forest pine plantation from 2002 to 2008 using Argos satellite technology. The home ranges for both adults and juveniles varied, ranging between 44 and 587 km2. The falcons occasionally utilised areas outside the forest and used stands of all ages within the forest, generally in proportion to their availability. For the most part, the juveniles remained within ca. 8 km of their nests and dispersed at 58, 69, and 68 days after fledging. Falcon movement information was obtained from an average of four location points per tracking day per falcon at a putative accuracy of 350 m. The transmitters, including their solar charge capability, performed well in the forest environment. The use of all stand ages highlights the importance of forestry practises that maintain a mosaic of different aged pine stands.

Nanoscale measurements of proton tracks using fluorescent nuclear track detectors

Energy Technology Data Exchange (ETDEWEB)

Sawakuchi, Gabriel O., E-mail: gsawakuchi@mdanderson.org; Sahoo, Narayan [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas 77030 (United States); Ferreira, Felisberto A. [Department of Nuclear Physics, University of Sao Paulo, SP 05508-090 (Brazil); McFadden, Conor H. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Hallacy, Timothy M. [Biophysics Program, Harvard University, Cambridge, Massachusetts 02138 (United States); Granville, Dal A. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, Ottawa, Ontario K1H 8L6 (Canada); Akselrod, Mark S. [Crystal Growth Division, Landauer, Inc., Stillwater, Oklahoma 74074 (United States)

2016-05-15

Purpose: The authors describe a method in which fluorescence nuclear track detectors (FNTDs), novel track detectors with nanoscale spatial resolution, are used to determine the linear energy transfer (LET) of individual proton tracks from proton therapy beams by allowing visualization and 3D reconstruction of such tracks. Methods: FNTDs were exposed to proton therapy beams with nominal energies ranging from 100 to 250 MeV. Proton track images were then recorded by confocal microscopy of the FNTDs. Proton tracks in the FNTD images were fit by using a Gaussian function to extract fluorescence amplitudes. Histograms of fluorescence amplitudes were then compared with LET spectra. Results: The authors successfully used FNTDs to register individual proton tracks from high-energy proton therapy beams, allowing reconstruction of 3D images of proton tracks along with delta rays. The track amplitudes from FNTDs could be used to parameterize LET spectra, allowing the LET of individual proton tracks from therapeutic proton beams to be determined. Conclusions: FNTDs can be used to directly visualize proton tracks and their delta rays at the nanoscale level. Because the track intensities in the FNTDs correlate with LET, they could be used further to measure LET of individual proton tracks. This method may be useful for measuring nanoscale radiation quantities and for measuring the LET of individual proton tracks in radiation biology experiments.

Monopole-track characteristics in plastic detectors

Science.gov (United States)

Ahlen, S. P.

1976-01-01

Total and restricted energy loss rates are calculated for magnetic monopoles of charge g = 137 e in Lexan polycarbonate. Range-energy curves are also presented. The restricted-energy-loss model is used to estimate the appearance of a monopole track in plastic detectors. The results are applied to the event observed by Price et al. and identified by them as a monopole. It is found that the observed etch rate is consistent with what one would expect for a slow magnetic monopole. These results should also be of use to other investigators for both the design and analysis of monopole experiments.

Upgrade tracking with the UT Hits

CERN Document Server

Gandini, P; Wang, J

2014-01-01

The performance of the LHCb tracking system for the upgrade on long tracks is evaluated in terms of efficiency and ghost rate reduction for several different sets of requirements. We find that the efficiency is quite high and that the ghost rate reduction is substantial. We also describe the current algorithm for adding UT hits to the tracks.

Acquisition, tracking, and pointing; Proceedings of the Meeting, Orlando, FL, Apr. 3, 4, 1986

Science.gov (United States)

Auelmann, Richard R. (Editor); Richard, Herbert L. (Editor)

1987-01-01

The present conference discusses the effect of target signatures on active tracking, the high resolution obtainable with a two-degrees-of-freedom angle sensor having a high update rate, solar object tracking for the Hubble Space Telescope, scaled experiments for the assessment of precise active tracking, and large aperture high-accuracy satellite laser tracking. Also discussed are laboratory test results for the Spaceborne Geodynamic Ranging System's high speed optical tracking system, jitter stabilization for precise optical pointing, scan stabilization and jitter control for an airborne telescope, a simulation of the Solar Optical Telescope's pointing performance, a microprocessor-based dual-speed angle converter, and image localization for alignment by means of adaptive preprocessing.

Precise Object Tracking under Deformation

International Nuclear Information System (INIS)

Saad, M.H.

2010-01-01

The precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This framework focuses on the precise object tracking under deformation such as scaling, rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high precession results. xiiiThe precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This framework focuses on the precise object tracking under deformation such as scaling, rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high

Synthesis of Algorithm for Range Measurement Equipment to Track Maneuvering Aircraft Using Data on Its Dynamic and Kinematic Parameters

Science.gov (United States)

Pudovkin, A. P.; Panasyuk, Yu N.; Danilov, S. N.; Moskvitin, S. P.

2018-05-01

The problem of improving automated air traffic control systems is considered through the example of the operation algorithm synthesis for a range measurement channel to track the aircraft, using its kinematic and dynamic parameters. The choice of the state and observation models has been justified, the computer simulations have been performed and the results of the investigated algorithms have been obtained.

High Dynamic Optimized Carrier Loop Improvement for Tracking Doppler Rates

Directory of Open Access Journals (Sweden)

Amirhossein Fereidountabar

2015-01-01

Full Text Available Mathematical analysis and optimization of a carrier tracking loop are presented. Due to fast changing of the carrier frequency in some satellite systems, such as Low Earth Orbit (LEO or Global Positioning System (GPS, or some planes like Unmanned Aerial Vehicles (UAVs, high dynamic tracking loops play a very important role. In this paper an optimized tracking loop consisting of a third-order Phase Locked Loop (PLL assisted by a second-order Frequency Locked Loop (FLL for UAVs is proposed and discussed. Based on this structure an optimal loop has been designed. The main advantages of this approach are the reduction of the computation complexity and smaller phase error. The paper shows the simulation results, comparing them with a previous work.

GPS Tracking of Free-Ranging Pigs to Evaluate Ring Strategies for the Control of Cysticercosis/Taeniasis in Peru.

Directory of Open Access Journals (Sweden)

Ian W Pray

2016-04-01

Full Text Available Taenia solium, a parasitic cestode that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. T. solium eggs are released into the environment through the stool of humans infected with an adult intestinal tapeworm (a condition called taeniasis, and cause cysticercosis when ingested by pigs or other humans. A control strategy to intervene within high-risk foci in endemic communities has been proposed as an alternative to mass antihelminthic treatment. In this ring strategy, antihelminthic treatment is targeted to humans and pigs residing within a 100 meter radius of a pig heavily-infected with cysticercosis. Our aim was to describe the roaming ranges of pigs in this region, and to evaluate whether the 100 meter radius rings encompass areas where risk factors for T. solium transmission, such as open human defecation and dense pig activity, are concentrated.In this study, we used Global Positioning System (GPS devices to track pig roaming ranges in two rural villages of northern Peru. We selected 41 pigs from two villages to participate in a 48-hour tracking period. Additionally, we surveyed all households to record the locations of open human defecation areas. We found that pigs spent a median of 82.8% (IQR: 73.5, 94.4 of their time roaming within 100 meters of their homes. The size of home ranges varied significantly by pig age, and 93% of the total time spent interacting with open human defecation areas occurred within 100 meters of pig residences.These results indicate that 100 meter radius rings around heavily-infected pigs adequately capture the average pig's roaming area (i.e., home range and represent an area where the great majority of exposure to human feces occurs.

GPS Tracking of Free-Ranging Pigs to Evaluate Ring Strategies for the Control of Cysticercosis/Taeniasis in Peru.

Science.gov (United States)

Pray, Ian W; Swanson, Dallas J; Ayvar, Viterbo; Muro, Claudio; Moyano, Luz M; Gonzalez, Armando E; Garcia, Hector H; O'Neal, Seth E

2016-04-01

Taenia solium, a parasitic cestode that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. T. solium eggs are released into the environment through the stool of humans infected with an adult intestinal tapeworm (a condition called taeniasis), and cause cysticercosis when ingested by pigs or other humans. A control strategy to intervene within high-risk foci in endemic communities has been proposed as an alternative to mass antihelminthic treatment. In this ring strategy, antihelminthic treatment is targeted to humans and pigs residing within a 100 meter radius of a pig heavily-infected with cysticercosis. Our aim was to describe the roaming ranges of pigs in this region, and to evaluate whether the 100 meter radius rings encompass areas where risk factors for T. solium transmission, such as open human defecation and dense pig activity, are concentrated. In this study, we used Global Positioning System (GPS) devices to track pig roaming ranges in two rural villages of northern Peru. We selected 41 pigs from two villages to participate in a 48-hour tracking period. Additionally, we surveyed all households to record the locations of open human defecation areas. We found that pigs spent a median of 82.8% (IQR: 73.5, 94.4) of their time roaming within 100 meters of their homes. The size of home ranges varied significantly by pig age, and 93% of the total time spent interacting with open human defecation areas occurred within 100 meters of pig residences. These results indicate that 100 meter radius rings around heavily-infected pigs adequately capture the average pig's roaming area (i.e., home range) and represent an area where the great majority of exposure to human feces occurs.

Human tracking over camera networks: a review

Science.gov (United States)

Hou, Li; Wan, Wanggen; Hwang, Jenq-Neng; Muhammad, Rizwan; Yang, Mingyang; Han, Kang

2017-12-01

In recent years, automated human tracking over camera networks is getting essential for video surveillance. The tasks of tracking human over camera networks are not only inherently challenging due to changing human appearance, but also have enormous potentials for a wide range of practical applications, ranging from security surveillance to retail and health care. This review paper surveys the most widely used techniques and recent advances for human tracking over camera networks. Two important functional modules for the human tracking over camera networks are addressed, including human tracking within a camera and human tracking across non-overlapping cameras. The core techniques of human tracking within a camera are discussed based on two aspects, i.e., generative trackers and discriminative trackers. The core techniques of human tracking across non-overlapping cameras are then discussed based on the aspects of human re-identification, camera-link model-based tracking and graph model-based tracking. Our survey aims to address existing problems, challenges, and future research directions based on the analyses of the current progress made toward human tracking techniques over camera networks.

Ranging Behaviour of Commercial Free-Range Broiler Chickens 2: Individual Variation.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2017-07-20

Little is known about broiler chicken ranging behaviour. Previous studies have monitored ranging behaviour at flock level but whether individual ranging behaviour varies within a flock is unknown. Using Radio Frequency Identification technology, we tracked 1200 individual ROSS 308 broiler chickens across four mixed sex flocks in two seasons on one commercial farm. Ranging behaviour was tracked from first day of range access (21 days of age) until 35 days of age in winter flocks and 44 days of age in summer flocks. We identified groups of chickens that differed in frequency of range visits: chickens that never accessed the range (13 to 67% of tagged chickens), low ranging chickens (15 to 44% of tagged chickens) that accounted for range visits and included chickens that used the range only once (6 to 12% of tagged chickens), and high ranging chickens (3 to 9% of tagged chickens) that accounted for 33 to 50% of all range visits. Males spent longer on the range than females in winter ( p ranging behaviour may help optimise ranging opportunities in free-range systems and is important to elucidate the potential welfare implications of ranging.

Mobile Tracking Systems Using Meter Class Reflective Telescopes

Science.gov (United States)

Sturzenbecher, K.; Ehrhorn, B.

This paper is a discussion on the use of large reflective telescopes on mobile tracking systems with modern instrument control systems. Large optics can be defined as reflective telescopes with an aperture of at least 20 inches in diameter. New carbon composite construction techniques allow for larger, stronger, and lighter telescopes ranging from 240 pounds for a 20 inch, to 800 pounds for a 32 inch, making them ideal for mobile tracking systems. These telescopes have better light gathering capability and produce larger images with greater detail at a longer range than conventional refractive lenses. In a mobile configuration these systems provide the ability to move the observation platform to the optimal location anywhere in the world. Mounting and systems integration - We will discuss how large telescopes can be physically fit to the mobile tracking system and the integration with the tracking systems' digital control system. We will highlight the remote control capabilities. We will discuss special calibration techniques available in a modern instrument control system such as star calibration, calibration of sensors. Tracking Performance - We will discuss the impact of using large telescopes on the performance of the mobile tracking system. We will highlight the capabilities for auto-tracking and sidereal rate tracking in a mobile mount. Large optics performance - We will discuss the advantages of two-mirror Ritchey-Chrétien reflective optics which offer in-focus imaging across the spectrum, from visible to Long Wave Infrared. These zero expansion optics won't lose figure or focus during temperature changes. And the carbon composite telescope tube is thermally inert. The primary mirror is a modern lightweight "dish" mirror for low thermal mass and is center supported/self balancing. Applications - We will discuss Visible - IR Imaging requirements, Optical Rangefinders, and capabilities for special filters to increase resolution in difficult conditions such as

Adaptive and accelerated tracking-learning-detection

Science.gov (United States)

Guo, Pengyu; Li, Xin; Ding, Shaowen; Tian, Zunhua; Zhang, Xiaohu

2013-08-01

An improved online long-term visual tracking algorithm, named adaptive and accelerated TLD (AA-TLD) based on Tracking-Learning-Detection (TLD) which is a novel tracking framework has been introduced in this paper. The improvement focuses on two aspects, one is adaption, which makes the algorithm not dependent on the pre-defined scanning grids by online generating scale space, and the other is efficiency, which uses not only algorithm-level acceleration like scale prediction that employs auto-regression and moving average (ARMA) model to learn the object motion to lessen the detector's searching range and the fixed number of positive and negative samples that ensures a constant retrieving time, but also CPU and GPU parallel technology to achieve hardware acceleration. In addition, in order to obtain a better effect, some TLD's details are redesigned, which uses a weight including both normalized correlation coefficient and scale size to integrate results, and adjusts distance metric thresholds online. A contrastive experiment on success rate, center location error and execution time, is carried out to show a performance and efficiency upgrade over state-of-the-art TLD with partial TLD datasets and Shenzhou IX return capsule image sequences. The algorithm can be used in the field of video surveillance to meet the need of real-time video tracking.

Track etch parameters and annealing kinetics assessment of protons of low energy in CR-39 detector

International Nuclear Information System (INIS)

Jain, R.K.; Kumar, Ashok; Singh, B.K.

2012-01-01

Highlights: ► We calibrate CR-39 detector with very low energy protons. ► We establish linear relationship between track diameter and time/energy up to 200 keV. ► We determine activation energy of annealing using different models. ► We justify concept of single annealing activation energy in CR-39. - Abstract: In this paper threshold of the registration sensitivity of very low energy proton in CR-39 is investigated. Irradiation of CR-39 (poly-allyl-diglycol carbonate) was carried out with very low energy mono energetic protons of 20–60 keV from a mini proton accelerator. Nearly 10 4 /cm 2 fluence of protons was used. The variation of track diameter with etching time as well as proton energy response curve was carefully calibrated. The bulk and track etch rates were measured by using proton track diameters. Bulk etch rate was also measured by the thickness of removed surface layer. The thermal annealing of proton track at temperatures ranging from 100 to 200 °C in CR-39 was studied by several models. Activation energy of annealed CR-39 detectors was calculated by slope of track etch rate and temperature plot. The data of proton tracks of 200, 250 and 300 keV from 400 kV Van-de-Graaff accelerator was also used and compared with the track diameters of different energies of proton.

The solid state track detectors for α-particles angular distribution measurements

International Nuclear Information System (INIS)

Bakr, M.H.S.

1978-01-01

The solid state track detectors technique is described in details from the point of view of applying them in nuclear reactions research. Using an optimum developing solution, the etching rate of polycarbonate detector was found to be 10.5 μ/hour. The energy resolution of this detector was estimated using 241 Am α-source at α-energies between 1 and 3 Mev. The scattering chamber designed for angular distribution measurements using solid state track detectors is described. A special schematic normograph for range-energy-degrading foils relation is given

77 FR 6949 - Tracking and Data Relay Satellite System (TDRSS) Rates for Non-U.S. Government Customers

Science.gov (United States)

2012-02-10

... Tracking and Data Relay Satellite System (TDRSS) Rates for Non- U.S. Government Customers AGENCY: National... customer flexibility, allowing more efficient use of the system. This notion was never implemented in the... commercial customers, as well as Arctic and Antarctic science programs. In this direct final rule, NASA is...

Robust online face tracking-by-detection

NARCIS (Netherlands)

Comaschi, F.; Stuijk, S.; Basten, T.; Corporaal, H.

2016-01-01

The problem of online face tracking from unconstrained videos is still unresolved. Challenges range from coping with severe online appearance variations to coping with occlusion. We propose RFTD (Robust Face Tracking-by-Detection), a system which combines tracking and detection into a single

Dosimetric benefit of DMLC tracking for conventional and sub-volume boosted prostate intensity-modulated arc radiotherapy

Science.gov (United States)

Pommer, Tobias; Falk, Marianne; Poulsen, Per R.; Keall, Paul J.; O'Brien, Ricky T.; Meidahl Petersen, Peter; Rosenschöld, Per Munck af

2013-04-01

This study investigated the dosimetric impact of uncompensated motion and motion compensation with dynamic multileaf collimator (DMLC) tracking for prostate intensity modulated arc therapy. Two treatment approaches were investigated; a conventional approach with a uniform radiation dose to the target volume and an intraprostatic lesion (IPL) boosted approach with an increased dose to a subvolume of the prostate. The impact on plan quality of optimizations with a leaf position constraint, which limited the distance between neighbouring adjacent MLC leaves, was also investigated. Deliveries were done with and without DMLC tracking on a linear acceleration with a high-resolution MLC. A cylindrical phantom containing two orthogonal diode arrays was used for dosimetry. A motion platform reproduced six patient-derived prostate motion traces, with the average displacement ranging from 1.0 to 8.9 mm during the first 75 s. A research DMLC tracking system was used for real-time motion compensation with optical monitoring for position input. The gamma index was used for evaluation, with measurements with a static phantom or the planned dose as reference, using 2% and 2 mm gamma criteria. The average pass rate with DMLC tracking was 99.9% (range 98.7-100%, measurement as reference), whereas the pass rate for untracked deliveries decreased distinctly as the average displacement increased, with an average pass rate of 61.3% (range 32.7-99.3%). Dose-volume histograms showed that DMLC tracking maintained the planned dose distributions in the presence of motion whereas traces with >3 mm average displacement caused clear plan degradation for untracked deliveries. The dose to the rectum and bladder had an evident dependence on the motion direction and amplitude for untracked deliveries, and the dose to the rectum was slightly increased for IPL boosted plans compared to conventional plans for anterior motion with large amplitude. In conclusion, optimization using a leaf position

A parameterization of nuclear track profiles in CR-39 detector

Science.gov (United States)

Azooz, A. A.; Al-Nia'emi, S. H.; Al-Jubbori, M. A.

2012-11-01

In this work, the empirical parameterization describing the alpha particles’ track depth in CR-39 detectors is extended to describe longitudinal track profiles against etching time for protons and alpha particles. MATLAB based software is developed for this purpose. The software calculates and plots the depth, diameter, range, residual range, saturation time, and etch rate versus etching time. The software predictions are compared with other experimental data and with results of calculations using the original software, TRACK_TEST, developed for alpha track calculations. The software related to this work is freely downloadable and performs calculations for protons in addition to alpha particles. Program summary Program title: CR39 Catalog identifier: AENA_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENA_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Copyright (c) 2011, Aasim Azooz Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met • Redistributions of source code must retain the above copyright, this list of conditions and the following disclaimer. • Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution This software is provided by the copyright holders and contributors “as is” and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright owner or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and

On the calculation of air flow rates to ventilate closed-type stations in subway with the double-track tunnel

Science.gov (United States)

Kiyanitsa, LA

2018-03-01

Metro is not only the most promising kind of public transport but also an important part of infrastructure in a modern city. As a place where large groups of people gather, subway is to ensure the required air exchange at the passenger platforms of the stations. The air flow rate for airing the stations is also determined based on the required temperature, humidity and MAC of gases. The present study estimates the required air flow rate at the passenger platform of the closed-type subway station with the double-track tunnel given the standard air temperature, humidity and gas concentration, as well as based on the condition of the specified air flow feed and air changes per hour. The article proposes the scheme of air recirculation from the double-track tunnel to the station.

Hardware test program for evaluation of baseline range-range rate sensor concept

Science.gov (United States)

1985-01-01

The baseline range/range rate sensor concept was evaluated. The Interrupted CW (ICW) mode of operation continued with emphasis on establishing the sensitivity of the video portion of the receiver was 7 dB less than the theoretical value. This departs from test results of previous implementations in which achieved sensitivity was within 1.5 to 2 dB of the theoretical value. Several potential causes of this discrepancy in performance were identified and are scheduled for further investigation. Results indicate that a cost savings in both per unit and program costs are realizable by eliminating one of the modes of operation. An acquisition (total program) cost savings of approximately 10% is projected by eliminating the CW mode of operation. The modified R/R sensor would operate in the ICW mode only and would provide coverage from initial acquisition at 12 nmi to within a few hundred feet of the OMV. If the ICW mode only were selected, then an accompanying sensor would be required to provide coverage from a few hundred feet to docking.

Development of etched nuclear tracks

International Nuclear Information System (INIS)

Somogyi, G.

1980-01-01

The theoretical description of the evolution of etched tracks in solid state nuclear track detectors is considered for different initial conditions, for the cases of constant and varying track etch rates, isotropic and anisotropic bulk etching as well as for thick and thin detectors. It is summarized how one can calculate the main parameters of etch-pit geometry, the track length, the axes of a surface track opening, track profile and track contour. The application of the theory of etch-track evolution is demonstrated with selected practical problems. Attention is paid to certain questions related to the determination of unknown track parameters and calculation of surface track sizes. Finally, the theory is extended to the description of the perforation and etch-hole evolution process in thin detectors, which is of particular interest for track radiography and nuclear filter production. (orig.)

Development of etched nuclear tracks

International Nuclear Information System (INIS)

Somogyi, G.

1979-01-01

The theoretical description of the evolution of etched tracks in solid state nuclear track detectors is considered for different initial conditions, for the cases of constant and varying track etch rates, isotopic and unisotropic bulk etching as well as for thick and thin detectors. It is summarized how the main parameters of etch-pit geometry, the track length, the axes of a surface track opening, the track profile and the track contour can be calculated. The application of the theory of etch-track evolution is demonstrated with selected practical problems. Attention is paid to certain questions related to the determination of unknown track parameters and calculation of surface track sizes. Finally, the theory is extended to the description of the perforation and etch-hole evolution process in thin detectors, which is of particular interest for track radiography and nuclear filter production. (author)

A spatial track formation model and its use for calculating etch-pit parameters of light nuclei

International Nuclear Information System (INIS)

Somogyi, G.; Scherzer, R.; Grabisch, K.; Enge, W.

1976-01-01

A generalized geometrical model of etch-pit formation in three dimensions is presented for nuclear particles entering isotropic solids at arbitrary angles of incidence. With this model one can calculate the relations between any particle parameter /Z = charge, M = mass, R = range, theta = angle of incidence/ and etching or track parameter /h = removed detector layer, L = track length, d = track diameter, etch-pit profile and contour/ for track etching rates varying monotonically along the trajectory of particles. Using a computer algorithm, calculations have been performed to study identification problems of nuclei of Z = 1-8 registered in a stack of polycarbonate sheets. For these calculations the etching rate ratio vs residual range curves were parametrized with a form of V -1 (R) = 1-Σasub(i) exp (- bsub(i)R) which does not involve the existence of a threshold for track registration. Particular attention was paid to the study of the evolution of etch-pit sizes for relatively high values of h. For this case, data are presented for the charge and isotope resolving power of the identification methods based on the relations L(R) of d(R). Calculations were also made to show the effect of the relative /parallel and opposite/ orientations between the directions of track etching and particle speed on etch-pit evolution. These studies offered new identification methods based on the determination of the curves L(parallel) vs L(opposite) and d(parallel) vs d(opposite), respectively. (orig.) [de

Moderating Argos location errors in animal tracking data

Science.gov (United States)

Douglas, David C.; Weinziert, Rolf; Davidson, Sarah C.; Kays, Roland; Wikelski, Martin; Bohrer, Gil

2012-01-01

1. The Argos System is used worldwide to satellite-track free-ranging animals, but location errors can range from tens of metres to hundreds of kilometres. Low-quality locations (Argos classes A, 0, B and Z) dominate animal tracking data. Standard-quality animal tracking locations (Argos classes 3, 2 and 1) have larger errors than those reported in Argos manuals.

NIR tracking assists sports medicine in junior basketball training

Science.gov (United States)

Paeglis, Roberts; Bluss, Kristaps; Rudzitis, Andris; Spunde, Andris; Brice, Tamara; Nitiss, Edgars

2011-07-01

We recorded eye movements of eight elite junior basketball players. We hypothesized that a more stable gaze is correlated to a better shot rate. Upon preliminary testing we invited male juniors whose eyes could be reliably tracked in a game situation. To these ends, we used a head-mounted video-based eye tracker. The participants had no record of ocular or other health issues. No significant differences were found between shots made with and without the tracker cap, Paired samples t-test yielded p= .130 for the far and p=..900 > .050 for the middle range shots. The players made 40 shots from common far and middle range locations, 5 and 4 meters respectively for aged 14 years As expected, a statistical correlation was found between gaze fixation (in milliseconds) for the far and middle range shot rates, r=.782, p=.03. Notably, juniors who fixated longer before a shot had a more stable fixation or a lower gaze dispersion (in tracker's screen pixels), r=-.786, p=.02. This finding was augmented by the observation that the gaze dispersion while aiming at the basket was less (i.e., gaze more stable) in those who were more likely to score. We derived a regression equation linking fixation duration to shot success. We advocate infra-red eye tracking as a means to monitor player selection and training success.

Momentum--"Evaluating Your Marketing Program: Measuring and Tracking Techniques."

Science.gov (United States)

Meservey, Lynne D.

1990-01-01

Suggests 10 tracking techniques for evaluating marketing performance. Techniques involve utilization rate, inquiry and source of inquiry tracking, appointment and interview tracking, enrollment conversion, cost per inquiry and per enrollment, retention rate, survey results, and "mystery shopper." (RJC)

Wire chamber requirements and tracking simulation studies for tracking systems at the superconducting super collider

International Nuclear Information System (INIS)

Hanson, G.G.; Niczyporuk, B.B.; Palounek, A.P.T.

1989-02-01

Limitations placed on wire chambers by radiation damage and rate requirements in the SSC environment are reviewed. Possible conceptual designs for wire chamber tracking systems which meet these requirements are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. Such computer simulation studies are necessary to determine the feasibility of wire chamber tracking systems for complex events in a high-rate environment such as the SSC. 11 refs., 9 figs., 1 tab

Properties of Polyethylene Naphthalate Track Membranes

CERN Document Server

Akimenko, S N; Orelovich, O L; Maekawa, J; Ioshida, M; Apel, P Yu

2002-01-01

Basic characteristics of track membranes made of polyethylene naphthalate (which is a polyester synthesized from dimethyl naphthalate and ethylene glycol) are studied and presented. Polyethylene naphthalate possesses some properties (mechanical strength, thermal and chemical stability), which make this polymer a promising material for the production of track membranes. Water flow rate and air flow rate characteristics, burst strength, wettability, and amount of extractables are determined. Surface structure and pore structure are examined using scanning electron microscopy. It is found that the pores in the membranes are cylindrical in shape. The measured water and air flow rates follow known theoretical relations for the transport in narrow capillaries. The burst strength of polyethylene naphthalate membranes is found to be similar to that of polyethylene terephthalate track membranes. Polyethylene naphthalate track membranes can be categorized as moderately hydrophilic. Being treated with boiling water, pol...

A method for the measurement of fission rates in fast neutron fields using solid state track detectors

International Nuclear Information System (INIS)

Hansen, W.; Vogel, W.

1984-04-01

Solid state track detectors (SSTDs) are increasingly used for the registration of radiation in different fields of nuclear physics. Because of their small sizes and masses and the absence of any electronics during exposure SSTDs do not cause distortions in the system to be investigated and are useful for measurements at such places being difficult of access. The elaboration of a method is described for fission rate measurements in fast neutron fields applying SSTDs and different fissionable isotopes which were electrodeposited on stainless steel backings. Experiences of the electrodeposition and results of quality checks are presented. The evaluation of the etched tracks is performed with spark counter technique. The dependence of the counting result on essential influence parameters is discussed. (author)

Precise object tracking under deformation

International Nuclear Information System (INIS)

Saad, M.H

2010-01-01

The precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This frame-work focuses on the precise object tracking under deformation such as scaling , rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high precession results.

Competencies of Track and Field coaches. An Exploratory Study

Directory of Open Access Journals (Sweden)

Alexandra Tripolitsioti

2012-01-01

Full Text Available The aim of this study was to construct a questionnaire to identify the knowledge and skills needed by track and field coaches in Greece to perform their role. Following standard procedures, an instrument with 42 items was constructed. Three hundred and forty nine Greek track and field coaches, who have been working 15+-2.8 y in the first and second division, aged 45+-4.4 y, participated in the study and rated the items of the questionnaire according to a Likert scale. Exploratory factor analysis revealed five factors comprising 22 competency statements: a field management techniques (7 items, b sport science (5 items, c injury prevention/crisis management (3 items; d biology (3 items; and e field training (4 items. The internal validity revealed a Cronbach’s alpha factor of 0.894 with subscales ranging from 0.657 to 0.886. Results also showed that demonstrating an understanding of specific inherent risks of sport activity and an understanding of psychology were the top rated competencies, while preparing a budget proposal and utilizing effective office procedures to handle registrations, reports, notices, etc., were the lower rated competencies. It is concluded that the questionnaire developed in this study is a reliable and valid instrument to measure the competencies of track and field coaches in Greece.

A Wide Lock-Range Referenceless CDR with Automatic Frequency Acquisition

OpenAIRE

Seon-Kyoo Lee; Young-Sang Kim; Hong-June Park; Jae-Yoon Sim

2011-01-01

A wide lock-range referenceless CDR circuit is proposed with an automatic tracking of data rate. For efficient frequency acquisition, a DLL-based loop is used with a simple phase/frequency detector to extract 1-bit period of input data stream. The CDR, implemented in a 65 nm CMOS, shows a lock range of 650 Mb/s-to-8 Gb/s and BER of less than 10-12 at 8 Gb/s with low power consumption.

A Wide Lock-Range Referenceless CDR with Automatic Frequency Acquisition

Directory of Open Access Journals (Sweden)

Seon-Kyoo Lee

2011-01-01

Full Text Available A wide lock-range referenceless CDR circuit is proposed with an automatic tracking of data rate. For efficient frequency acquisition, a DLL-based loop is used with a simple phase/frequency detector to extract 1-bit period of input data stream. The CDR, implemented in a 65 nm CMOS, shows a lock range of 650 Mb/s-to-8 Gb/s and BER of less than 10-12 at 8 Gb/s with low power consumption.

A many particle-tracking detector with drift planes and segmented cathode readout

International Nuclear Information System (INIS)

Fischer, J.; Lissauer, D.; Ludlam, T.; Makowiecki, D.; O'Brien, E.; Radeka, V.; Rescia, S.; Rogers, L.; Smith, G.C.; Stephani, D.; Yu, B.; Greene, S.V.; Hemmick, T.K.; Mitchell, J.T.; Shivakumar, B.

1990-01-01

We describe the design and performance of a detector system for tracking charged particles in an environment of high track density and rates up to 1 MHz. The system operates in the forward spectrometer of the BNL Heavy Ion experiment E814 and uses principles of general interest in high rate, high multiplicity applications such as at RHIC or SSC. We require our system to perform over a large dynamic range, detecting singly charged particles as well as fully ionized relativistic 28 Si. Results on gas gain saturation, δ-ray suppression, and overall detector performance in the presence of a 14.6 GeV/nucleon 28 Si beam and a 14 GeV proton beam are presented. 6 refs., 9 figs

Multi-rate h2 tracking control with mixed continuous-discrete performance criteria

International Nuclear Information System (INIS)

Kahane, A.C.; Palmor, Z.J.; Mirkin, L.

1998-01-01

Control goals defined both in continuous and discrete time arise naturally in many sampled-data tracking control problems. The design methods found in the literature deal with each kind of those control goals separately, over-emphasizing one kind at the expense of the other. We formulate and solve these tracking control problems as an H2 optimization problem with a mixed continuous/discrete performance criterion. It is argued that the proposed setup enables tradeoff between the various control goals in a natural manner and thus leads to better tracking characteristics

Simultaneous tracking and activity recognition

DEFF Research Database (Denmark)

Manfredotti, Cristina Elena; Fleet, David J.; Hamilton, Howard J.

2011-01-01

be used to improve the prediction step of the tracking, while, at the same time, tracking information can be used for online activity recognition. Experimental results in two different settings show that our approach 1) decreases the error rate and improves the identity maintenance of the positional......Many tracking problems involve several distinct objects interacting with each other. We develop a framework that takes into account interactions between objects allowing the recognition of complex activities. In contrast to classic approaches that consider distinct phases of tracking and activity...... tracking and 2) identifies the correct activity with higher accuracy than standard approaches....

Real-time heart rate measurement for multi-people using compressive tracking

Science.gov (United States)

Liu, Lingling; Zhao, Yuejin; Liu, Ming; Kong, Lingqin; Dong, Liquan; Ma, Feilong; Pang, Zongguang; Cai, Zhi; Zhang, Yachu; Hua, Peng; Yuan, Ruifeng

2017-09-01

The rise of aging population has created a demand for inexpensive, unobtrusive, automated health care solutions. Image PhotoPlethysmoGraphy(IPPG) aids in the development of these solutions by allowing for the extraction of physiological signals from video data. However, the main deficiencies of the recent IPPG methods are non-automated, non-real-time and susceptible to motion artifacts(MA). In this paper, a real-time heart rate(HR) detection method for multiple subjects simultaneously was proposed and realized using the open computer vision(openCV) library, which consists of getting multiple subjects' facial video automatically through a Webcam, detecting the region of interest (ROI) in the video, reducing the false detection rate by our improved Adaboost algorithm, reducing the MA by our improved compress tracking(CT) algorithm, wavelet noise-suppression algorithm for denoising and multi-threads for higher detection speed. For comparison, HR was measured simultaneously using a medical pulse oximetry device for every subject during all sessions. Experimental results on a data set of 30 subjects show that the max average absolute error of heart rate estimation is less than 8 beats per minute (BPM), and the processing speed of every frame has almost reached real-time: the experiments with video recordings of ten subjects under the condition of the pixel resolution of 600× 800 pixels show that the average HR detection time of 10 subjects was about 17 frames per second (fps).

The artificial retina for track reconstruction at the LHC crossing rate

CERN Document Server

Abba, A.; Citterio, M.; Caponio, F.; Cusimano, A.; Geraci, A.; Marino, P.; Morello, M.J.; Neri, N.; Punzi, G.; Piucci, A.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.

2016-01-01

We present the results of an R&D study for a specialized processor capable of precisely reconstructing events with hundreds of charged-particle tracks in pixel and silicon strip detectors at $40\\,\\rm MHz$, thus suitable for processing LHC events at the full crossing frequency. For this purpose we design and test a massively parallel pattern-recognition algorithm, inspired to the current understanding of the mechanisms adopted by the primary visual cortex of mammals in the early stages of visual-information processing. The detailed geometry and charged-particle's activity of a large tracking detector are simulated and used to assess the performance of the artificial retina algorithm. We find that high-quality tracking in large detectors is possible with sub-microsecond latencies when the algorithm is implemented in modern, high-speed, high-bandwidth FPGA devices.

The artificial retina for track reconstruction at the LHC crossing rate

Science.gov (United States)

Abba, A.; Bedeschi, F.; Citterio, M.; Caponio, F.; Cusimano, A.; Geraci, A.; Marino, P.; Morello, M. J.; Neri, N.; Punzi, G.; Piucci, A.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.

2016-04-01

We present the results of an R&D study for a specialized processor capable of precisely reconstructing events with hundreds of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus suitable for processing LHC events at the full crossing frequency. For this purpose we design and test a massively parallel pattern-recognition algorithm, inspired to the current understanding of the mechanisms adopted by the primary visual cortex of mammals in the early stages of visual-information processing. The detailed geometry and charged-particle's activity of a large tracking detector are simulated and used to assess the performance of the artificial retina algorithm. We find that high-quality tracking in large detectors is possible with sub-microsecond latencies when the algorithm is implemented in modern, high-speed, high-bandwidth FPGA devices.

An artificial retina processor for track reconstruction at the LHC crossing rate

Science.gov (United States)

Bedeschi, F.; Cenci, R.; Marino, P.; Morello, M. J.; Ninci, D.; Piucci, A.; Punzi, G.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.; Walsh, J.

2017-10-01

The goal of the INFN-RETINA R&D project is to develop and implement a computational methodology that allows to reconstruct events with a large number (> 100) of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus matching the requirements for processing LHC events at the full bunch-crossing frequency. Our approach relies on a parallel pattern-recognition algorithm, dubbed artificial retina, inspired by the early stages of image processing by the brain. In order to demonstrate that a track-processing system based on this algorithm is feasible, we built a sizable prototype of a tracking processor tuned to 3 000 patterns, based on already existing readout boards equipped with Altera Stratix III FPGAs. The detailed geometry and charged-particle activity of a large tracking detector currently in operation are used to assess its performances. We report on the test results with such a prototype.

A study on alpha particles range in Cr-39

International Nuclear Information System (INIS)

Ibrahim, Z.A.; Talaat, T.M.; Abdel-Aziz, Kh.M.A.; El-Asser, M.R.

2000-01-01

Cr-39 plastic nuclear track detector has been used in range determination of alpha particles. A set of experiments was carried out for studying alpha energy and track diameter relationships. This work was done under the optimum conditions of Cr-39 etching in 6.25 N NaOH at 70 degree C for various etching times. Determination of alpha range in Cr-39 recorders was studied at different energy values using the over etched track profile technique. Data are discussed within the framework of track formation theory in plastic foils, comparison between experimental and theoretical values of alpha range is included

Spatio-temporal hotspots of satellite-tracked arctic foxes reveal a large detection range in a mammalian predator.

Science.gov (United States)

Lai, Sandra; Bêty, Joël; Berteaux, Dominique

2015-01-01

The scale at which animals perceive their environment is a strong fitness determinant, yet few empirical estimates of animal detection ranges exist, especially in mammalian predators. Using daily Argos satellite tracking of 26 adult arctic foxes (Vulpes lagopus) during a single winter in the High Canadian Arctic, we investigated the detection range of arctic foxes by detecting hotspots of fox activity on the sea ice. While maintaining territories in the tundra, these solitary foragers occasionally used the sea ice where they sometimes formed spatio-temporal hotspots, likely scavenging on marine mammal carcasses. We detected 35 movements by 13 individuals forming five hotspots. Foxes often traveled more than 10 km, and up to 40 km, to reach hotspots, which lasted one-two weeks and could gather up to 12 individuals. The likelihood of a fox joining a hotspot was neither influenced by its distance from the hotspot nor by the distance of its home range to the coast. Observed traveling distances may indicate a high detection range in arctic foxes, and our results suggest their ability to detect food sources on the sea ice from their terrestrial home range. While revealing a wide knowledge gap regarding resource detection abilities in mammalian predators, our study provides estimates of detection range useful for interpreting and modeling animal movements. It also allows a better understanding of foraging behavior and navigation capacity in terrestrial predators.

Graph Model Based Indoor Tracking

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

2009-01-01

The tracking of the locations of moving objects in large indoor spaces is important, as it enables a range of applications related to, e.g., security and indoor navigation and guidance. This paper presents a graph model based approach to indoor tracking that offers a uniform data management...

Study etching characteristics of a track detector CR-39 with ultraviolet laser irradiation

International Nuclear Information System (INIS)

Dwaikat, Nidal; Iida, Toshiyuki; Sato, Fuminobu; Kato, Yushi; Ishikawa, Ippei; Kada, Wataru; Kishi, Atsuya; Sakai, Makoto; Ihara, Yohei

2007-01-01

The effect of pulsed ultraviolet Indium-doped Yttrium Aluminum Garnet (UV-In:YAG) laser of λ=266 nm, pulse energy 42 mJ/pulse at repetition rate10 Hz on the etching characteristics of Japanese CR-39 was studied at various energy intensities. Fifteen detectors were divided into two sets, each of seven samples and one sample was kept as a reference.The first set (post-exposed) was first exposed to alpha radiation with close contact to 241 Am and then treated in air with laser in the energy intensity range from 40 to160 J/cm 2 , 20 J/cm 2 in step. The second set (pre-exposed) was irradiated in reverse process (laser+alpha) with the same sources as the first set and under the same condition. The laser energy intensities ranged between 20 and 140 J/cm 2 , 20 J/cm 2 in step. For post-exposed samples (alpha+laser) bulk etch rate decreases up to 60 J/cm 2 and increases thereafter, while for pre-exposed samples (laser+alpha) the bulk etch rate oscillates without showing any precise periodicity. The bulk etch rate for both sets was found to be the same at 60≤energy intensity≤80 J/cm 2 and this may indicate that the same structural changes have happened. The track etch rate was found to be equal to the bulk etch rate for both sets, so the sensitivity is constant. In both sets several changes on the detector surfaces: tracks of different sizes and shapes and high density within the laser spot were observed. Out of the laser spot, the tracks become larger and lower density, indicating cross-linking and scission have happened, simultaneously, on the same surface as a result of UV-laser irradiation

Background for a new standard on pass-by measurement of combined roughness, track decay rate and vibroacoustic transfer functions

NARCIS (Netherlands)

Dittrich, M.G.; Létourneaux, F.; Dupuis, H.

2013-01-01

A measurement method for combined roughness, track decay rates and transfer functions derived from rail vibration during a train pass-by was initially developed in the late nineties [1]. This method has been then later implemented in software tools [2] and applied in several countries for various

Mechanism of track formation by charged particles in inorganic and organic solid-state track detectors

International Nuclear Information System (INIS)

Doerschel, B.; Pretzsch, G.; Streubel, G.

1979-01-01

Knowledge of the individual phases of track formation mechanism is necessary in some applications of solid-state track detectors. The generation of latent tracks is described by energy transfer processes of the charged particles along their paths using several different models. Etchability of the latent tracks is discussed on the basis of some distinct criteria taking into account different fractions of energy release by the primary and secondary particles during track generation. If these etchability criteria for latent tracks are fulfilled, visual particle tracks can be produced by a chemical etching process. Etch pit formation depends on the etching conditions. The geometrical parameters of the etching pits are given on the basis of known etching rates. Evaluation of individual particle tracks or determination of track density yields results depending on both the properties of the particles and the etching conditions. Determination of particle energy and particle fluence is discussed as an example. (author)

Elephant (Loxodonta africana home ranges in Sabi Sand Reserve and Kruger National Park: a five-year satellite tracking study.

Directory of Open Access Journals (Sweden)

Bindi Thomas

Full Text Available During a five-year GPS satellite tracking study in Sabi Sand Reserve (SSR and Kruger National Park (KNP we monitored the daily movements of an elephant cow (Loxodonta africana from September 2003 to August 2008. The study animal was confirmed to be part of a group of seven elephants therefore her position is representative of the matriarchal group. We found that the study animal did not use habitat randomly and confirmed strong seasonal fidelity to its summer and winter five-year home ranges. The cow's summer home range was in KNP in an area more than four times that of her SSR winter home range. She exhibited clear park habitation with up to three visits per year travelling via a well-defined northern or southern corridor. There was a positive correlation between the daily distance the elephant walked and minimum daily temperature and the elephant was significantly closer to rivers and artificial waterholes than would be expected if it were moving randomly in KNP and SSR. Transect lines established through the home ranges were surveyed to further understand the fine scale of the landscape and vegetation representative of the home ranges.

Elephant (Loxodonta africana) home ranges in Sabi Sand Reserve and Kruger National Park: a five-year satellite tracking study.

Science.gov (United States)

Thomas, Bindi; Holland, John D; Minot, Edward O

2008-01-01

During a five-year GPS satellite tracking study in Sabi Sand Reserve (SSR) and Kruger National Park (KNP) we monitored the daily movements of an elephant cow (Loxodonta africana) from September 2003 to August 2008. The study animal was confirmed to be part of a group of seven elephants therefore her position is representative of the matriarchal group. We found that the study animal did not use habitat randomly and confirmed strong seasonal fidelity to its summer and winter five-year home ranges. The cow's summer home range was in KNP in an area more than four times that of her SSR winter home range. She exhibited clear park habitation with up to three visits per year travelling via a well-defined northern or southern corridor. There was a positive correlation between the daily distance the elephant walked and minimum daily temperature and the elephant was significantly closer to rivers and artificial waterholes than would be expected if it were moving randomly in KNP and SSR. Transect lines established through the home ranges were surveyed to further understand the fine scale of the landscape and vegetation representative of the home ranges.

A wide range survey meter for estimating γ- and β-dose rates

International Nuclear Information System (INIS)

Jones, A.R.

1980-09-01

A survey meter has been developed to measure β-dose rates in the range 0.1 - 100 rad/h (1 mGy/h - 1 Gy/h) and γ-dose rates in the range 1 mrad/h - 100 rad/h (10 μGy/h-1 Gy/h). It also provides an audible warning of high γ-dose rates and an audible and visible warning when a predetermined γ-dose is exceeded. The report describes the design of the survey meter and presents data measured on the performance of an engineering prototype. Factors which affect performance and have been investigated are temperature, battery voltage (and type of battery), GM counter counting loss, direction of incident radiation, and energy of γ-rays. Finally, the application and calibration of the survey meter are discussed. (auth)

Qualitative indices and enhancement rate of CT pulmonary angiography in patients with suspected pulmonary embolism: Comparison between test bolus and bolus-tracking methods

Directory of Open Access Journals (Sweden)

Maryam Moradi

2016-01-01

Full Text Available Background: The aim of the present study was to assess the qualitative indices and enhancement rate of computed tomographic pulmonary angiography (CTPA in patients with suspected pulmonary embolism using Test bolus and Bolus-tracking techniques. Materials and Methods: Fifty-two patients with suspected pulmonary embolism that passed informed consent were randomly divided in the two groups. In each group, demographic characteristics, qualitative indices, and enhancement rate of CTPA were recorded. Results: The diagnostic result obtained in majority of the participants in the two groups (88.5 % in Test bolus group vs. 73.1% in the Bolus tracking group. In the case of quantitative variables, no statistically significant differences were found between the groups (P > 0.05. The only statistically significant difference between the two groups is average of "X-ray dose". Conclusion: The results of our study show that there is no statistically significant difference between the Bolus Tracking and Test Bolus techniques for producing more homogeneous enhancement.

Applying dual-laser spot positions measurement technology on a two-dimensional tracking measurement system

International Nuclear Information System (INIS)

Lee, Hau-Wei; Chen, Chieh-Li

2009-01-01

This paper presents a two-dimensional tracking measurement system with a tracking module, which consists of two stepping motors, two laser diodes and a four separated active areas segmented position sensitive detector (PSD). The PSD was placed on a two-dimensional moving stage and used as a tracking target. The two laser diodes in the tracking module were directly rotated to keep the laser spots on the origin of the PSD. The two-dimensional position of the target PSD on the moving stage is determined from the distance between the two motors and the tracking angles of the two laser diodes, which are rotated by the two stepping motors, respectively. In order to separate the four positional values of the two laser spots on one PSD, the laser diodes were modulated by two distinct frequencies. Multiple-laser spot position measurement technology was used to separate the four positional values of the two laser spots on the PSD. The experimental results show that the steady-state voltage shift rate is about 0.2% and dynamic cross-talk rate is smaller than 2% when the two laser spots are projected on one PSD at the same time. The measurement errors of the x and y axial positions of the two-dimensional tracking system were less than 1% in the measuring range of 20 mm. The results demonstrate that multiple-laser spot position measurement technology can be employed in a two-dimensional tracking measurement system

Fission track geochronology of Eastern Ghats

Energy Technology Data Exchange (ETDEWEB)

Virk, H S; Koul, S L; Singh, S [Punjabi Univ., Patiala (India). Dept. of Physics

1978-12-01

Fission track geochronology of Eastern Ghats has been established by using fission track technique in dating micaceous and accessory minerals occurring in the region. Annealing studies confirm that radiation damage fossil tracks can be erased in minerals under intense metamorphic episodes thus resetting the geological clock. The fission track ages of the minerals range between 450 +- 5 m.y. to 622 +- 148 m.y. It is concluded that f.t. ages of the minerals date the last metamorphic event of the Eastern Ghats, known as the Indian Ocean Cycle.

Ranging Behaviour of Commercial Free-Range Broiler Chickens 1: Factors Related to Flock Variability.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2017-07-20

Little is known about the ranging behaviour of chickens. Understanding ranging behaviour is required to improve management and shed and range design to ensure optimal ranging opportunities. Using Radio Frequency Identification technology, we tracked 300 individual broiler chickens in each of four mixed sex ROSS 308 flocks on one commercial farm across two seasons. Ranging behaviour was tracked from the first day of range access (21 days of age) until 35 days of age in winter and 44 days of age in summer. Range use was higher than previously reported from scan sampling studies. More chickens accessed the range in summer (81%) than winter (32%; p range use was greater in summer flocks (4.4 ± 0.1 visits for a total of 26.3 ± 0.8 min/day) than winter flocks (3.2 ± 0.2 visits for a total of 7.9 ± 1.0 min/day). Seasonal differences were only marginally explained by weather conditions and may reflect the reduction in range exposure between seasons (number of days, hours per day, and time of day). Specific times of the day ( p ranging and external factors that may explain ranging preferences.

Reducing Delay in Diagnosis: Multistage Recommendation Tracking.

Science.gov (United States)

Wandtke, Ben; Gallagher, Sarah

2017-11-01

The purpose of this study was to determine whether a multistage tracking system could improve communication between health care providers, reducing the risk of delay in diagnosis related to inconsistent communication and tracking of radiology follow-up recommendations. Unconditional recommendations for imaging follow-up of all diagnostic imaging modalities excluding mammography (n = 589) were entered into a database and tracked through a multistage tracking system for 13 months. Tracking interventions were performed for patients for whom completion of recommended follow-up imaging could not be identified 1 month after the recommendation due date. Postintervention compliance with the follow-up recommendation required examination completion or clinical closure (i.e., biopsy, limited life expectancy or death, or subspecialist referral). Baseline radiology information system checks performed 1 month after the recommendation due date revealed timely completion of 43.1% of recommended imaging studies at our institution before intervention. Three separate tracking interventions were studied, showing effectiveness between 29.0% and 57.8%. The multistage tracking system increased the examination completion rate to 70.5% (a 52% increase) and reduced the rate of unknown follow-up compliance and the associated risk of delay in diagnosis to 13.9% (a 74% decrease). Examinations completed after tracking intervention generated revenue of 4.1 times greater than the labor cost. Performing sequential radiology recommendation tracking interventions can substantially reduce the rate of unknown follow-up compliance and add value to the health system. Unknown follow-up compliance is a risk factor for delay in diagnosis, a form of preventable medical error commonly identified in malpractice claims involving radiologists and office-based practitioners.

Track structure for low energy ions including charge exchange processes

International Nuclear Information System (INIS)

Uehara, S.; Nikjoo, H.

2002-01-01

The model and development is described of a new generation of Monte Carlo track structure codes. The code LEAHIST simulates full slowing down of low-energy proton history tracks in the range 1 keV-1 MeV and the code LEAHIST simulates low-energy alpha particle history tracks in the range 1 keV-8 MeV in water. All primary ion interactions are followed down to 1 keV and all electrons to 1 eV. Tracks of secondary electrons ejected by ions were traced using the electron code KURBUC. Microdosimetric parameters derived by analysis of generated tracks are presented. (author)

Laser radiation effect on radiation-induced defects in heavy ion tracks in dielectrics

International Nuclear Information System (INIS)

Egorov, A.N.; Zhiryakov, B.M.; Kushin, V.V.; Lyapidevskij, V.K.; Khokhlov, N.B.

1988-01-01

Possibility of laser radiation resonance effect on radiation-induced defects in heavy ion tracks in dielectric materials is investigated. Absorption spectra in infrared, visible and ultraviolet ranges for cellulose nitrate samples irradiated by 6 MeV/nucleon 58 Ni ions and reactor gamma radiation are measured. Absorption spectra for irradiated and reference samples are presented. Two absorption bands λ 1 =0.33 μm (E 1 =3.9 eV) and λ 2 =0.72 μm (E 2 =1.7 eV) are detected. Etching rate decrease in a track under laser radiation effect is noticed. 3 refs.; 1 fig

Understanding the uplift pattern in Mesozoic and Cenozoic,, eastern Dabie area, China using fission track dating of apatite

International Nuclear Information System (INIS)

Wu Qianhong; Liu Shunsheng

2002-01-01

By using the fission track dating technique, a preliminary study was carried out on the fission track ages (FTA) of apatite, their distribution patterns and hints over the tectonics activities during Mesozoic and Cenozoic in the east Dabie area. Attempts were also made to improve the conventional statistical method for the tracks. Ranging from 59.4 +- 3.4 Ma to 105.6 +- 9.8 Ma, the FTA results of apatite spread in the wide range and increased rapidly from the east to the west area. Sine 95 Ma, the uplift rate has been quite slow and asymmetry. The FTA value in the middle area of Xiaotian-Mozitan Fault may imply its uplift in Cretaceous. The faulting should be the main control factor for the uplift of this area

Triton, deuteron and proton responses of the CR-39 track detector

Energy Technology Data Exchange (ETDEWEB)

Yamauchi, Tomoya; Matsumoto, Hiroyoshi; Oda, Keiji [Kobe Univ. of Mercantile Marine (Japan)

1996-07-01

In the present study, we assessed the response of the CR-39 detector to proton, deuteron and triton from their etch-pit growth curves obtained by multi-step etching technique and the difference among their track registration properties was discussed. In order to avoid incorrect evaluation due to the missing track effect, particle irradiation was performed at various incident energies. The response function, S(R), etch rate ratio, S, as a function of the residual range, R, was experimentally evaluated for all hydrogen isotopes by this method. In the next, we obtained another form of response functions of S(E), S({beta}) and S(LET{sub 200}), which were presented as functions of the particle energy, E, the particle velocity, {beta}(=v/c), and the linear energy transfer in the case where the cut-off energy is 200 eV, LET{sub 200}, respectively. These information will be useful also in understanding the fundamentals of the latent track formation mechanism in the plastic track detectors. (J.P.N.)

Hardware accelerator design for tracking in smart camera

Science.gov (United States)

Singh, Sanjay; Dunga, Srinivasa Murali; Saini, Ravi; Mandal, A. S.; Shekhar, Chandra; Vohra, Anil

2011-10-01

Smart Cameras are important components in video analysis. For video analysis, smart cameras needs to detect interesting moving objects, track such objects from frame to frame, and perform analysis of object track in real time. Therefore, the use of real-time tracking is prominent in smart cameras. The software implementation of tracking algorithm on a general purpose processor (like PowerPC) could achieve low frame rate far from real-time requirements. This paper presents the SIMD approach based hardware accelerator designed for real-time tracking of objects in a scene. The system is designed and simulated using VHDL and implemented on Xilinx XUP Virtex-IIPro FPGA. Resulted frame rate is 30 frames per second for 250x200 resolution video in gray scale.

Particle tracking at the SSC

International Nuclear Information System (INIS)

Freeman, J.E.; Williams, H.H.

1984-01-01

The intent of this study was to get some idea of how difficult tracking will be at √s = 40 TeV for events involving momentum transfers in the vicinity of several hundred GeV. While some studies have been done to determine the minimum separation between two random tracks as a function of radius, the authors know of no previous study in this energy range which has considered the ''observability'' of a track along its entire path length, including the effects of magnetic field and finite double track resolution. They have not considered the effects of pileup due to multiple events, concentrating instead of the inherent difficulties of single high p/sub T/ events

Controlling type I error rate for fast track drug development programmes.

Science.gov (United States)

Shih, Weichung J; Ouyang, Peter; Quan, Hui; Lin, Yong; Michiels, Bart; Bijnens, Luc

2003-03-15

The U.S. Food and Drug Administration (FDA) Modernization Act of 1997 has a Section (No. 112) entitled 'Expediting Study and Approval of Fast Track Drugs' (the Act). In 1998, the FDA issued a 'Guidance for Industry: the Fast Track Drug Development Programs' (the FTDD programmes) to meet the requirement of the Act. The purpose of FTDD programmes is to 'facilitate the development and expedite the review of new drugs that are intended to treat serious or life-threatening conditions and that demonstrate the potential to address unmet medical needs'. Since then many health products have reached patients who suffered from AIDS, cancer, osteoporosis, and many other diseases, sooner by utilizing the Fast Track Act and the FTDD programmes. In the meantime several scientific issues have also surfaced when following the FTDD programmes. In this paper we will discuss the concept of two kinds of type I errors, namely, the 'conditional approval' and the 'final approval' type I errors, and propose statistical methods for controlling them in a new drug submission process. Copyright 2003 John Wiley & Sons, Ltd.

Comparative effectiveness of correction strategies in connected discourse tracking.

Science.gov (United States)

Lunato, K E; Weisenberger, J M

1994-10-01

The effectiveness of four correction strategies commonly used in connected discourse tracking was investigated in the present study. The strategies were 1) verbatim repetition of a word or phrase; 2) use of antonyms or synonyms as cues; 3) use of phonemic cues, with no whole word repetition; and 4) going back or ahead in the text, with no repetition of the missed segment. Four normal-hearing adults served as listeners. Live-voice presentation of text by two female talkers was employed for all conditions. Listeners were tested in two stimulus presentation modes, speechreading alone and speechreading plus a multichannel tactile aid. Results indicated that strategy 1, repetition of the missed segment, produced the highest tracking rates, significantly higher than any of the other strategies. Strategy 2 produced the lowest tracking rates. Strategies 1 and 3 yielded the lowest percentage of initially missed words, or blockages, and strategy 4 the highest percentage. Significantly higher tracking rates were found under the speechreading plus tactile aid presentation mode, compared with speechreading alone. Further, tracking rates increased significantly from the beginning to the end of training. Data were compared with a more typical CDT task, in which all correction strategies were operative, and results showed little difference in tracking rates between this task and the constrained CDT employing only strategy 1. Overall, results suggest that simple repetition of missed segments is an effective correction strategy for CDT and argue for its inclusion in computer-assisted tracking implementations.

The Track Imaging Cerenkov Experiment

Science.gov (United States)

Wissel, S. A.; Byrum, K.; Cunningham, J. D.; Drake, G.; Hays, E.; Horan, D.; Kieda, D.; Kovacs, E.; Macgill, S.; Nodulman, L.;

Active MRI tracking for robotic assisted FUS

Science.gov (United States)

Xiao, Xu; Huang, Zhihong; Melzer, Andreas

2017-03-01

MR guided FUS is a noninvasive method producing thermal necrosis at the position of tumors with high accuracy and temperature control. Because the typical size of the ultrasound focus is smaller than the area of interested treatment tissues, focus repositioning become necessary to achieve multiple sonications to cover the whole targeted area. Using MR compatible mechanical actuators could help the ultrasound beam to reach a wider treatment range than using electrical beam steering technique and more flexibility in position the transducer. An active MR tracking technique was combined into the MRgFUS system to help locating the position of the mechanical actuator and the FUS transducer. For this study, a precise agar reference model was designed and fabricated to test the performance of the active tracking technique when it was used on the MR-compatible robotics InnoMotion™ (IBSMM, Engineering spol. s r.o. / Ltd, Czech Republic). The precision, tracking range and positioning speed of the combined robotic FUS system were evaluated in this study. Compared to the existing MR guided HIFU systems, the combined robotic system with active tracking techniques provides a potential that allows the FUS treatment to operate in a larger spatial range and with a faster speed, which is one of the main challenges for organ motion tracking.

VeloTT tracking for LHCb Run II

CERN Document Server

Bowen, Espen Eie; Tresch, Marco

2016-01-01

This note describes track reconstruction in the LHCb tracking system upstream of the magnet, combining VELO tracks with hits in the TT sub-detector. The implementation of the VeloTT algorithm and its performance in terms of track reconstruction efficiency, ghost rate and execution time are presented. The algorithm has been rewritten for use in the first software trigger level for LHCb Run II. The momentum and charge information obtained for the VeloTT tracks (due to a fringe magnetic field between the VELO and TT sub-detectors) can reduce the total execution time for the full tracking sequence.

Parameterization-based tracking for the P2 experiment

Energy Technology Data Exchange (ETDEWEB)

Sorokin, Iurii [Institut fuer Kernphysik and PRISMA Cluster of Excellence, Mainz (Germany); Collaboration: P2-Collaboration

2016-07-01

The P2 experiment at the new MESA accelerator in Mainz aims to determine the weak mixing angle by measuring the parity-violating asymmetry in elastic electron-proton scattering at low momentum transfer. To achieve an unprecedented precision an order of 10{sup 11} scattered electrons per second have to be acquired. %within the acceptance. Whereas the tracking system is not required to operate at such high rates, every attempt is made to achieve as high rate capability as possible. The P2 tracking system will consist of four planes of high-voltage monolithic active pixel sensors (HV-MAPS). With the present preliminary design one expects about 150 signal electron tracks and 20000 background hits (from bremsstrahlung photons) per plane in every 50 ns readout frame at the full rate. In order to cope with this extreme combinatorial background in on-line mode, a parameterization-based tracking is considered as a possible solution. The idea is to transform the hit positions into a set of weakly correlated quantities, and to find simple (e.g. polynomial) functions of these quantities, that would give the required characteristics of the track (e.g. momentum). The parameters of the functions are determined from a sample of high-quality tracks, taken either from a simulation, or reconstructed in a conventional way from a sample of low-rate data.

Studies on implementation of pellet tracking in hadron physics experiments

Directory of Open Access Journals (Sweden)

Pyszniak A.

2014-01-01

Full Text Available A system for optical tracking of frozen hydrogen microsphere targets (pellets has been designed. It is intended for the upcoming hadron physics experiment PANDA at FAIR, Darmstadt, Germany. With such a tracking system one can reconstruct the positions of the individual pellets at the time of a hadronic interaction in the offline event analysis. This gives information on the position of the primary interaction vertex with an accuracy of a few 100 µm, which is very useful e.g. for reconstruction of charged particle tracks and secondary vertices and for background suppression. A study has been done at the WASA detector setup (Forschungszentrum Jülich, Germany to check the possibility of classification of hadronic events as originating in pellets or in background. The study has been done based on the instantaneous rate a Long Range TDC which was used to determine if a pellet was present in the accelerator beam region. It was clearly shown that it is possible to distinguish the two event classes. Also, an experience was gained with operation of two synchronized systems operating in different time scales, as it will also be the case with the optical pellet tracking.

Fabrication of nanoporous nuclear track membranes

International Nuclear Information System (INIS)

Peng Liangqiang; Wang Shicheng; Ju Xin; Masaru Yoshida; Yasunari Maekawa

2001-01-01

Polyethylene terephthalate (PET) and polycarbonate (PC) films were irradiated by S, Kr and Xe ions and were illuminated with ultraviolet light. The normalized track etch rate for PET and PC films etched in different conditions were measured by conductometric experiments. It is shown that normalized track etch rate can be over 1000 for PET films, 2000 for PC films under optimized condition. TEM photographs of copper nanowires electroplated into nanoporous nuclear track membranes show that the narrowest wire diameter of copper nanowires is 20 nm and that the pore diameter calculated by conductometric experiments is in agreement with the wire diameter measured by TEM when the pore diameter is over 30 nm

Improved electromagnetic tracking for catheter path reconstruction with application in high-dose-rate brachytherapy.

Science.gov (United States)

Lugez, Elodie; Sadjadi, Hossein; Joshi, Chandra P; Akl, Selim G; Fichtinger, Gabor

2017-04-01

Electromagnetic (EM) catheter tracking has recently been introduced in order to enable prompt and uncomplicated reconstruction of catheter paths in various clinical interventions. However, EM tracking is prone to measurement errors which can compromise the outcome of the procedure. Minimizing catheter tracking errors is therefore paramount to improve the path reconstruction accuracy. An extended Kalman filter (EKF) was employed to combine the nonlinear kinematic model of an EM sensor inside the catheter, with both its position and orientation measurements. The formulation of the kinematic model was based on the nonholonomic motion constraints of the EM sensor inside the catheter. Experimental verification was carried out in a clinical HDR suite. Ten catheters were inserted with mean curvatures varying from 0 to [Formula: see text] in a phantom. A miniaturized Ascension (Burlington, Vermont, USA) trakSTAR EM sensor (model 55) was threaded within each catheter at various speeds ranging from 7.4 to [Formula: see text]. The nonholonomic EKF was applied on the tracking data in order to statistically improve the EM tracking accuracy. A sample reconstruction error was defined at each point as the Euclidean distance between the estimated EM measurement and its corresponding ground truth. A path reconstruction accuracy was defined as the root mean square of the sample reconstruction errors, while the path reconstruction precision was defined as the standard deviation of these sample reconstruction errors. The impacts of sensor velocity and path curvature on the nonholonomic EKF method were determined. Finally, the nonholonomic EKF catheter path reconstructions were compared with the reconstructions provided by the manufacturer's filters under default settings, namely the AC wide notch and the DC adaptive filter. With a path reconstruction accuracy of 1.9 mm, the nonholonomic EKF surpassed the performance of the manufacturer's filters (2.4 mm) by 21% and the raw EM

Online track detection in triggerless mode for INO

Science.gov (United States)

Jain, A.; Padmini, S.; Joseph, A. N.; Mahesh, P.; Preetha, N.; Behere, A.; Sikder, S. S.; Majumder, G.; Behera, S. P.

2018-03-01

The India based Neutrino Observatory (INO) is a proposed particle physics research project to study the atmospheric neutrinos. INO-Iron Calorimeter (ICAL) will consist of 28,800 detectors having 3.6 million electronic channels expected to activate with 100 Hz single rate, producing data at a rate of 3 GBps. Data collected contains a few real hits generated by muon tracks and the remaining noise-induced spurious hits. Estimated reduction factor after filtering out data of interest from generated data is of the order of 103. This makes trigger generation critical for efficient data collection and storage. Trigger is generated by detecting coincidence across multiple channels satisfying trigger criteria, within a small window of 200 ns in the trigger region. As the probability of neutrino interaction is very low, track detection algorithm has to be efficient and fast enough to process 5 × 106 events-candidates/s without introducing significant dead time, so that not even a single neutrino event is missed out. A hardware based trigger system is presently proposed for on-line track detection considering stringent timing requirements. Though the trigger system can be designed with scalability, a lot of hardware devices and interconnections make it a complex and expensive solution with limited flexibility. A software based track detection approach working on the hit information offers an elegant solution with possibility of varying trigger criteria for selecting various potentially interesting physics events. An event selection approach for an alternative triggerless readout scheme has been developed. The algorithm is mathematically simple, robust and parallelizable. It has been validated by detecting simulated muon events for energies of the range of 1 GeV-10 GeV with 100% efficiency at a processing rate of 60 μs/event on a 16 core machine. The algorithm and result of a proof-of-concept for its faster implementation over multiple cores is presented. The paper also

VeloUT tracking for the LHCb Upgrade

CERN Document Server

Bowen, E

2014-01-01

This note describes track reconstruction in the LHCb tracking system upstream of the magnet, namely the VELO and UT sub-detectors. The implementation of the VeloUT algorithm and its performance in terms of track reconstruction efficiency, ghost rate and execution time per event are presented. The algorithm has been optimised for use in the Upgrade software trigger of LHCb. The momentum information obtained for the VeloUT tracks (due to a fringe magnetic field between the VELO and UT sub-detectors) can reduce the total execution time per event for the full tracking sequence. The performance of the tracking sequence with and without the use of VeloUT tracks is also presented.

First evaluation of the feasibility of MLC tracking using ultrasound motion estimation

Energy Technology Data Exchange (ETDEWEB)

Fast, Martin F., E-mail: martin.fast@icr.ac.uk; O’Shea, Tuathan P., E-mail: tuathan.oshea@nhs.net; Nill, Simeon; Oelfke, Uwe; Harris, Emma J. [Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London SM2 5NG (United Kingdom)

2016-08-15

Purpose: To quantify the performance of the Clarity ultrasound (US) imaging system (Elekta AB, Stockholm, Sweden) for real-time dynamic multileaf collimator (MLC) tracking. Methods: The Clarity calibration and quality assurance phantom was mounted on a motion platform moving with a periodic sine wave trajectory. The detected position of a 30 mm hypoechogenic sphere within the phantom was continuously reported via Clarity’s real-time streaming interface to an in-house tracking and delivery software and subsequently used to adapt the MLC aperture. A portal imager measured MV treatment field/MLC apertures and motion platform positions throughout each experiment to independently quantify system latency and geometric error. Based on the measured range of latency values, a prostate stereotactic body radiation therapy (SBRT) delivery was performed with three realistic motion trajectories. The dosimetric impact of system latency on MLC tracking was directly measured using a 3D dosimeter mounted on the motion platform. Results: For 2D US imaging, the overall system latency, including all delay times from the imaging and delivery chain, ranged from 392 to 424 ms depending on the lateral sector size. For 3D US imaging, the latency ranged from 566 to 1031 ms depending on the elevational sweep. The latency-corrected geometric root-mean squared error was below 0.75 mm (2D US) and below 1.75 mm (3D US). For the prostate SBRT delivery, the impact of a range of system latencies (400–1000 ms) on the MLC tracking performance was minimal in terms of gamma failure rate. Conclusions: Real-time MLC tracking based on a noninvasive US input is technologically feasible. Current system latencies are higher than those for x-ray imaging systems, but US can provide full volumetric image data and the impact of system latency was measured to be small for a prostate SBRT case when using a US-like motion input.

First evaluation of the feasibility of MLC tracking using ultrasound motion estimation

International Nuclear Information System (INIS)

Fast, Martin F.; O’Shea, Tuathan P.; Nill, Simeon; Oelfke, Uwe; Harris, Emma J.

2016-01-01

Purpose: To quantify the performance of the Clarity ultrasound (US) imaging system (Elekta AB, Stockholm, Sweden) for real-time dynamic multileaf collimator (MLC) tracking. Methods: The Clarity calibration and quality assurance phantom was mounted on a motion platform moving with a periodic sine wave trajectory. The detected position of a 30 mm hypoechogenic sphere within the phantom was continuously reported via Clarity’s real-time streaming interface to an in-house tracking and delivery software and subsequently used to adapt the MLC aperture. A portal imager measured MV treatment field/MLC apertures and motion platform positions throughout each experiment to independently quantify system latency and geometric error. Based on the measured range of latency values, a prostate stereotactic body radiation therapy (SBRT) delivery was performed with three realistic motion trajectories. The dosimetric impact of system latency on MLC tracking was directly measured using a 3D dosimeter mounted on the motion platform. Results: For 2D US imaging, the overall system latency, including all delay times from the imaging and delivery chain, ranged from 392 to 424 ms depending on the lateral sector size. For 3D US imaging, the latency ranged from 566 to 1031 ms depending on the elevational sweep. The latency-corrected geometric root-mean squared error was below 0.75 mm (2D US) and below 1.75 mm (3D US). For the prostate SBRT delivery, the impact of a range of system latencies (400–1000 ms) on the MLC tracking performance was minimal in terms of gamma failure rate. Conclusions: Real-time MLC tracking based on a noninvasive US input is technologically feasible. Current system latencies are higher than those for x-ray imaging systems, but US can provide full volumetric image data and the impact of system latency was measured to be small for a prostate SBRT case when using a US-like motion input.

Vibro-acoustic performance of newly designed tram track structures

Science.gov (United States)

Haladin, Ivo; Lakušić, Stjepan; Ahac, Maja

2017-09-01

Rail vehicles in interaction with a railway structure induce vibrations that are propagating to surrounding structures and cause noise disturbance in the surrounding areas. Since tram tracks in urban areas often share the running surface with road vehicles one of top priorities is to achieve low maintenance and long lasting structure. Research conducted in scope of this paper gives an overview of newly designed tram track structures designated for use on Zagreb tram network and their performance in terms of noise and vibration mitigation. Research has been conducted on a 150 m long test section consisted of three tram track types: standard tram track structure commonly used on tram lines in Zagreb, optimized tram structure for better noise and vibration mitigation and a slab track with double sleepers embedded in a concrete slab, which presents an entirely new approach of tram track construction in Zagreb. Track has been instrumented with acceleration sensors, strain gauges and revision shafts for inspection. Relative deformations give an insight into track structure dynamic load distribution through the exploitation period. Further the paper describes vibro-acoustic measurements conducted at the test site. To evaluate the track performance from the vibro-acoustical standpoint, detailed analysis of track decay rate has been analysed. Opposed to measurement technique using impact hammer for track decay rate measurements, newly developed measuring technique using vehicle pass by vibrations as a source of excitation has been proposed and analysed. Paper gives overview of the method, it’s benefits compared to standard method of track decay rate measurements and method evaluation based on noise measurements of the vehicle pass by.

Lightweight GPS-tags, one giant leap for wildlife tracking? An assessment approach.

Directory of Open Access Journals (Sweden)

Mariano R Recio

Full Text Available Recent technological improvements have made possible the development of lightweight GPS-tagging devices suitable to track medium-to-small sized animals. However, current inferences concerning GPS performance are based on heavier designs, suitable only for large mammals. Lightweight GPS-units are deployed close to the ground, on species selecting micro-topographical features and with different behavioural patterns in comparison to larger mammal species. We assessed the effects of vegetation, topography, motion, and behaviour on the fix success rate for lightweight GPS-collar across a range of natural environments, and at the scale of perception of feral cats (Felis catus. Units deployed at 20 cm above the ground in sites of varied vegetation and topography showed that trees (native forest and shrub cover had the largest influence on fix success rate (89% on average; whereas tree cover, sky availability, number of satellites and horizontal dilution of position (HDOP were the main variables affecting location error (±39.5 m and ±27.6 m before and after filtering outlier fixes. Tests on HDOP or number of satellites-based screening methods to remove inaccurate locations achieved only a small reduction of error and discarded many accurate locations. Mobility tests were used to simulate cats' motion, revealing a slightly lower performance as compared to the fixed sites. GPS-collars deployed on 43 cats showed no difference in fix success rate by sex or season. Overall, fix success rate and location error values were within the range of previous tests carried out with collars designed for larger species. Lightweight GPS-tags are a suitable method to track medium to small size species, hence increasing the range of opportunities for spatial ecology research. However, the effects of vegetation, topography and behaviour on location error and fix success rate need to be evaluated prior to deployment, for the particular study species and their habitats.

The rate of beneficial mutations surfing on the wave of a range expansion.

Directory of Open Access Journals (Sweden)

Rémi Lehe

Full Text Available Many theoretical and experimental studies suggest that range expansions can have severe consequences for the gene pool of the expanding population. Due to strongly enhanced genetic drift at the advancing frontier, neutral and weakly deleterious mutations can reach large frequencies in the newly colonized regions, as if they were surfing the front of the range expansion. These findings raise the question of how frequently beneficial mutations successfully surf at shifting range margins, thereby promoting adaptation towards a range-expansion phenotype. Here, we use individual-based simulations to study the surfing statistics of recurrent beneficial mutations on wave-like range expansions in linear habitats. We show that the rate of surfing depends on two strongly antagonistic factors, the probability of surfing given the spatial location of a novel mutation and the rate of occurrence of mutations at that location. The surfing probability strongly increases towards the tip of the wave. Novel mutations are unlikely to surf unless they enjoy a spatial head start compared to the bulk of the population. The needed head start is shown to be proportional to the inverse fitness of the mutant type, and only weakly dependent on the carrying capacity. The precise location dependence of surfing probabilities is derived from the non-extinction probability of a branching process within a moving field of growth rates. The second factor is the mutation occurrence which strongly decreases towards the tip of the wave. Thus, most successful mutations arise at an intermediate position in the front of the wave. We present an analytic theory for the tradeoff between these factors that allows to predict how frequently substitutions by beneficial mutations occur at invasion fronts. We find that small amounts of genetic drift increase the fixation rate of beneficial mutations at the advancing front, and thus could be important for adaptation during species invasions.

Expanded Operational Temperature Range for Space Rated Li-Ion Batteries, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Quallion's response to this solicitation calls for expanding the nominal operation range of its space rated lithium ion cells, while maintaining their long life...

Eye tracking in user experience design

CERN Document Server

Romano Bergstorm, Jennifer

2014-01-01

Eye Tracking for User Experience Design explores the many applications of eye tracking to better understand how users view and interact with technology. Ten leading experts in eye tracking discuss how they have taken advantage of this new technology to understand, design, and evaluate user experience. Real-world stories are included from these experts who have used eye tracking during the design and development of products ranging from information websites to immersive games. They also explore recent advances in the technology which tracks how users interact with mobile devices, large-screen displays and video game consoles. Methods for combining eye tracking with other research techniques for a more holistic understanding of the user experience are discussed. This is an invaluable resource to those who want to learn how eye tracking can be used to better understand and design for their users. * Includes highly relevant examples and information for those who perform user research and design interactive experi...

Expanded Operational Temperature Range for Space Rated Li-Ion Batteries, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Quallion's Phase II proposal calls for expanding the nominal operation range of its space rated lithium ion cells, while maintaining their long life capabilities. To...

Relationship between thermotectonic evolution of Serra do Mar mountain range and Santos Basin, SP, Brazil, accessed through fission track analysis in apatite

International Nuclear Information System (INIS)

Hadler, J.C; Tello, S.C.A; Iunes, P.J.; Guedes, S; Hackspacher, P; Paulo, S.R; Ribeiro, L.F.B

2001-01-01

the laboratory use. Through these models, these times are extrapolated to geological ones. The most employed model was proposed by Laslett et al. (1987). It is based on the best fit of the annealing data set by Green et al. (1986). By this model, a track length distribution can be obtained from both the thermal history and age of a sample. However, what one can obtain through the FTM is the track length distribution and what one wants is the thermal history. The employment of the model in this 'inverse' way was proposed by Lutz and Omar (1991) and is widely accepted since then. In this work, the 'inverse model' was utilized to determine the thermal history of a group of samples collected in Serra do Mar Mountain Range (SMMR). As these samples were collected in the same tectonic unit, a common thermal history is a plausible expectation. To show the consistence of this analysis, the relationship between the obtained thermal history and stratigraphic data of Santos Basin is presented (au)

Online track reconstruction at hadron colliders

International Nuclear Information System (INIS)

Amerio, Silvia; Bettini, Marco; Nicoletto, Marino; Crescioli, Francesco; Bucciantonio, Martina; DELL'ORSO, Mauro; Piendibene, Marco; VOLPI, Guido; Annovi, Alberto; Catastini, Pierluigi; Giannetti, Paola; Lucchesi, Donatella

2010-01-01

Real time event reconstruction plays a fundamental role in High Energy Physics experiments. Reducing the rate of data to be saved on tape from millions to hundreds per second is critical. In order to increase the purity of the collected samples, rate reduction has to be coupled with the capability to simultaneously perform a first selection of the most interesting events. A fast and efficient online track reconstruction is important to effectively trigger on leptons and/or displaced tracks from b-quark decays. This talk will be an overview of online tracking techniques in different HEP environments: we will show how H1 experiment at HERA faced the challenges of online track reconstruction implementing pattern matching and track linking algorithms on CAMs and FPGAs in the Fast Track Processor (FTT). The pattern recognition technique is also at the basis of the Silicon Vertex Trigger (SVT) at the CDF experiment at Tevatron: coupled to a very fast fitting phase, SVT allows to trigger on displaced tracks, thus greatly increasing the efficiency for the hadronic B decay modes. A recent upgrade of the SVT track fitter, the Giga-fitter, can perform more than 1 fit/ns and further improves the CDF online trigger capabilities at high luminosity. At SLHC, where luminosities will be 2 orders of magnitude greater than Tevatron, online tracking will be much more challenging: we will describe CMS future plans for a Level-1 track trigger and the Fast Tracker (FTK) processor at the ATLAS experiment, based on the Giga-fitter architecture and designed to provide high quality tracks reconstructed over the entire detector in time for a Level-2 trigger decision.luminosity. At SLHC, where luminosities will be 2 orders of magnitude greater than Tevatron, online tracking will be much more challenging: we will describe CMS future plans for a Level-1 track trigger and the Fast Tracker (FTK) processor at the Atlas experiment, based on the Giga-fitter architecture and designed to provide high

Underwater Acoustic Target Tracking: A Review

Science.gov (United States)

Han, Ying; Fan, Liying

2018-01-01

Advances in acoustic technology and instrumentation now make it possible to explore marine resources. As a significant component of ocean exploration, underwater acoustic target tracking has aroused wide attention both in military and civil fields. Due to the complexity of the marine environment, numerous techniques have been proposed to obtain better tracking performance. In this paper, we survey over 100 papers ranging from innovative papers to the state-of-the-art in this field to present underwater tracking technologies. Not only the related knowledge of acoustic tracking instrument and tracking progress is clarified in detail, but also a novel taxonomy method is proposed. In this paper, algorithms for underwater acoustic target tracking are classified based on the methods used as: (1) instrument-assisted methods; (2) mode-based methods; (3) tracking optimization methods. These algorithms are compared and analyzed in the aspect of dimensions, numbers, and maneuvering of the tracking target, which is different from other survey papers. Meanwhile, challenges, countermeasures, and lessons learned are illustrated in this paper. PMID:29301318

New ways of polymeric ion track characterization

International Nuclear Information System (INIS)

Fink, D.; Mueller, M.; Ghosh, S.; Dwivedi, K.K.; Vacik, J.; Hnatowicz, V.; Cervena, J.; Kobayashi, Y.; Hirata, K.

1999-01-01

New ways have been applied for characterization of ion tracks in polymers in the last few years, which are essentially related to depth profile determinations of ions, molecules, or positrons penetrating into these tracks. In combination with tomography, the first three-dimensional results have been obtained. Extensive diffusion simulations accompanying the measurements have enabled us to obtain a better understanding of the transport processes going on in ion tracks. This paper gives an overview about the range of new possibilities accessible by these techniques, and summarizes the presently obtained understanding of ion tracks in polymers

Particle Filter Tracking without Dynamics

Directory of Open Access Journals (Sweden)

Jaime Ortegon-Aguilar

2007-01-01

Full Text Available People tracking is an interesting topic in computer vision. It has applications in industrial areas such as surveillance or human-machine interaction. Particle Filters is a common algorithm for people tracking; challenging situations occur when the target's motion is poorly modelled or with unexpected motions. In this paper, an alternative to address people tracking is presented. The proposed algorithm is based in particle filters, but instead of using a dynamical model, it uses background subtraction to predict future locations of particles. The algorithm is able to track people in omnidirectional sequences with a low frame rate (one or two frames per second. Our approach can tackle unexpected discontinuities and changes in the direction of the motion. The main goal of the paper is to track people from laboratories, but it has applications in surveillance, mainly in controlled environments.

Double tracks test site characterization report

International Nuclear Information System (INIS)

1996-05-01

This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy's (DOE) Streamlined Approach for Environmental Restoration (SAFER)

Water-Column Stratification Observed along an AUV-Tracked Isotherm

Science.gov (United States)

Zhang, Y.; Messié, M.; Ryan, J. P.; Kieft, B.; Stanway, M. J.; Hobson, B.; O'Reilly, T. C.; Raanan, B. Y.; Smith, J. M.; Chavez, F.

2016-02-01

Studies of marine physical, chemical and microbiological processes benefit from observing in a Lagrangian frame of reference, i.e. drifting with ambient water. Because these processes can be organized relative to specific density or temperature ranges, maintaining observing platforms within targeted environmental ranges is an important observing strategy. We have developed a novel method to enable a Tethys-class long-range autonomous underwater vehicle (AUV) (which has a propeller and a buoyancy engine) to track a target isotherm in buoyancy-controlled drift mode. In this mode, the vehicle shuts off its propeller and autonomously detects the isotherm and stays with it by actively controlling the vehicle's buoyancy. In the June 2015 CANON (Controlled, Agile, and Novel Observing Network) Experiment in Monterey Bay, California, AUV Makai tracked a target isotherm for 13 hours to study the coastal upwelling system. The tracked isotherm started from 33 m depth, shoaled to 10 m, and then deepened to 29 m. The thickness of the tracked isotherm layer (within 0.3°C error from the target temperature) increased over this duration, reflecting weakened stratification around the isotherm. During Makai's isotherm tracking, another long-range AUV, Daphne, acoustically tracked Makai on a circular yo-yo trajectory, measuring water-column profiles in Makai's vicinity. A wave glider also acoustically tracked Makai, providing sea surface measurements on the track. The presented method is a new approach for studying water-column stratification, but requires careful analysis of the temporal and spatial variations mingled in the vehicles' measurements. We will present a synthesis of the water column's stratification in relation to the upwelling conditions, based on the in situ measurements by the mobile platforms, as well as remote sensing and mooring data.

Development of the ZEUS central tracking detector

Science.gov (United States)

Brooks, C. B.; Bullock, F. W.; Cashmore, R. J.; Devenish, R. C.; Foster, B.; Fraser, T. J.; Gibson, M. D.; Gilmore, R. S.; Gingrich, D.; Harnew, N.; Hart, J. C.; Heath, G. P.; Hiddleston, J.; Holmes, A. R.; Jamdagni, A. K.; Jones, T. W.; Llewellyn, T. J.; Long, K. R.; Lush, G. J.; Malos, J.; Martin, N. C.; McArthur, I.; McCubbin, N. A.; McQuillan, D.; Miller, D. B.; Mobayyen, M. M.; Morgado, C.; Nash, J.; Nixon, G.; Parham, A. G.; Payne, B. T.; Roberts, J. H. C.; Salmon, G.; Saxon, D. H.; Sephton, A. J.; Shaw, D.; Shaw, T. B.; Shield, P. D.; Shulman, J.; Silvester, I.; Smith, S.; Strachan, D. E.; Tapper, R. J.; Tkaczyk, S. M.; Toudup, L. W.; Wallis, E. W.; Wastie, R.; Wells, J.; White, D. J.; Wilson, F. F.; Yeo, K. L.; ZEUS-UK Collaboration

1989-11-01

The design concept and development of the ZEUS central tracking detector is described. This is a cylindrical drift chamber designed for track reconstruction, electron identification and event triggering in a high-crossing-rate, high-magnetic-field environment.

Feasibility studies for a wireless 60 GHz tracking detector readout

International Nuclear Information System (INIS)

Dittmeier, S.; Schöning, A.; Soltveit, H.K.; Wiedner, D.

2016-01-01

The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m"2) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

Feasibility studies for a wireless 60 GHz tracking detector readout

Energy Technology Data Exchange (ETDEWEB)

Dittmeier, S., E-mail: dittmeier@physi.uni-heidelberg.de; Schöning, A.; Soltveit, H.K.; Wiedner, D.

2016-09-11

The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m{sup 2}) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

Development of the ZEUS central tracking detector

International Nuclear Information System (INIS)

Brooks, C.B.; Cashmore, R.J.; Gingrich, D.; Harnew, N.; Heath, G.P.; Holmes, A.R.; Martin, N.C.; McArthur, I.; Nash, J.; Salmon, G.; Shield, P.D.; Silvester, I.; Smith, S.; Wastie, R.; Wells, J.; Jamdagni, A.K.; McQuillan, D.; Miller, D.B.; Mobayyen, M.M.; Shulman, J.; Toudup, L.W.

1989-01-01

The design concept and development of the ZEUS central tracking detector is described. This is a cylindrical drift chamber designed for track reconstruction, electron identification and event triggering in a high-crossing-rate, high-magnetic-field environment. (orig.)

Analyzing Track Responses to Train Braking

DEFF Research Database (Denmark)

Bose, Tulika; Levenberg, Eyal; Zania, Varvara

2018-01-01

The objective of this study was to suggest a response analysis framework for railway tracks that are subjected to braking. An analytical formulation was developed, in which the rail–track system was modeled as an infinite beam supported by an orthogonal Winkler foundation consisting of linear...... a response analysis framework for railway tracks that are subjected to braking. An analytical formulation was developed, in which the rail–track system was modeled as an infinite beam supported by an orthogonal Winkler foundation consisting of linear springs in perpendicular directions. The spring constants...... springs in perpendicular directions. The spring constants were varied over a wide range in order to represent different track types. Braking loads were simulated as representative sets of vertical and longitudinal forces, either concentrated or distributed. Considering a realistic set of model parameters...

The ATLAS Track Extrapolation Package

CERN Document Server

Salzburger, A

2007-01-01

The extrapolation of track parameters and their associated covariances to destination surfaces of different types is a very frequent process in the event reconstruction of high energy physics experiments. This is amongst other reasons due to the fact that most track and vertex fitting techniques are based on the first and second momentum of the underlying probability density distribution. The correct stochastic or deterministic treatment of interactions with the traversed detector material is hereby crucial for high quality track reconstruction throughout the entire momentum range of final state particles that are produced in high energy physics collision experiments. This document presents the main concepts, the algorithms and the implementation of the newly developed, powerful ATLAS track extrapolation engine. It also emphasises on validation procedures, timing measurements and the integration into the ATLAS offline reconstruction software.

Robust detection and tracking of annotations for outdoor augmented reality browsing

Science.gov (United States)

Langlotz, Tobias; Degendorfer, Claus; Mulloni, Alessandro; Schall, Gerhard; Reitmayr, Gerhard; Schmalstieg, Dieter

2011-01-01

A common goal of outdoor augmented reality (AR) is the presentation of annotations that are registered to anchor points in the real world. We present an enhanced approach for registering and tracking such anchor points, which is suitable for current generation mobile phones and can also successfully deal with the wide variety of viewing conditions encountered in real life outdoor use. The approach is based on on-the-fly generation of panoramic images by sweeping the camera over the scene. The panoramas are then used for stable orientation tracking, while the user is performing only rotational movements. This basic approach is improved by several new techniques for the re-detection and tracking of anchor points. For the re-detection, specifically after temporal variations, we first compute a panoramic image with extended dynamic range, which can better represent varying illumination conditions. The panorama is then searched for known anchor points, while orientation tracking continues uninterrupted. We then use information from an internal orientation sensor to prime an active search scheme for the anchor points, which improves matching results. Finally, global consistency is enhanced by statistical estimation of a global rotation that minimizes the overall position error of anchor points when transforming them from the source panorama in which they were created, to the current view represented by a new panorama. Once the anchor points are redetected, we track the user's movement using a novel 3-degree-of-freedom orientation tracking approach that combines vision tracking with the absolute orientation from inertial and magnetic sensors. We tested our system using an AR campus guide as an example application and provide detailed results for our approach using an off-the-shelf smartphone. Results show that the re-detection rate is improved by a factor of 2 compared to previous work and reaches almost 90% for a wide variety of test cases while still keeping the ability

Robust detection and tracking of annotations for outdoor augmented reality browsing.

Science.gov (United States)

Langlotz, Tobias; Degendorfer, Claus; Mulloni, Alessandro; Schall, Gerhard; Reitmayr, Gerhard; Schmalstieg, Dieter

2011-08-01

A common goal of outdoor augmented reality (AR) is the presentation of annotations that are registered to anchor points in the real world. We present an enhanced approach for registering and tracking such anchor points, which is suitable for current generation mobile phones and can also successfully deal with the wide variety of viewing conditions encountered in real life outdoor use. The approach is based on on-the-fly generation of panoramic images by sweeping the camera over the scene. The panoramas are then used for stable orientation tracking, while the user is performing only rotational movements. This basic approach is improved by several new techniques for the re-detection and tracking of anchor points. For the re-detection, specifically after temporal variations, we first compute a panoramic image with extended dynamic range, which can better represent varying illumination conditions. The panorama is then searched for known anchor points, while orientation tracking continues uninterrupted. We then use information from an internal orientation sensor to prime an active search scheme for the anchor points, which improves matching results. Finally, global consistency is enhanced by statistical estimation of a global rotation that minimizes the overall position error of anchor points when transforming them from the source panorama in which they were created, to the current view represented by a new panorama. Once the anchor points are redetected, we track the user's movement using a novel 3-degree-of-freedom orientation tracking approach that combines vision tracking with the absolute orientation from inertial and magnetic sensors. We tested our system using an AR campus guide as an example application and provide detailed results for our approach using an off-the-shelf smartphone. Results show that the re-detection rate is improved by a factor of 2 compared to previous work and reaches almost 90% for a wide variety of test cases while still keeping the ability

An alternative way to track the hot money in turbulent times

Science.gov (United States)

Sensoy, Ahmet

2015-02-01

During recent years, networks have proven to be an efficient way to characterize and investigate a wide range of complex financial systems. In this study, we first obtain the dynamic conditional correlations between filtered exchange rates (against US dollar) of several countries and introduce a time-varying threshold correlation level to define dynamic strong correlations between these exchange rates. Then, using evolving networks obtained from strong correlations, we propose an alternative approach to track the hot money in turbulent times. The approach is demonstrated for the time period including the financial turmoil of 2008. Other applications are also discussed.

The Pisa pre-main sequence tracks and isochrones. A database covering a wide range of Z, Y, mass, and age values

Science.gov (United States)

Tognelli, E.; Prada Moroni, P. G.; Degl'Innocenti, S.

2011-09-01

Context. In recent years new observations of pre-main sequence stars (pre-MS) with Z ≤ Z⊙ have been made available. To take full advantage of the continuously growing amount of data of pre-MS stars in different environments, we need to develop updated pre-MS models for a wide range of metallicity to assign reliable ages and masses to the observed stars. Aims: We present updated evolutionary pre-MS models and isochrones for a fine grid of mass, age, metallicity, and helium values. Methods: We use a standard and well-tested stellar evolutionary code (i.e. FRANEC), that adopts outer boundary conditions from detailed and realistic atmosphere models. In this code, we incorporate additional improvements to the physical inputs related to the equation of state and the low temperature radiative opacities essential to computing low-mass stellar models. Results: We make available via internet a large database of pre-MS tracks and isochrones for a wide range of chemical compositions (Z = 0.0002-0.03), masses (M = 0.2-7.0 M⊙), and ages (1-100 Myr) for a solar-calibrated mixing length parameter α (i.e. 1.68). For each chemical composition, additional models were computed with two different mixing length values, namely α = 1.2 and 1.9. Moreover, for Z ≥ 0.008, we also provided models with two different initial deuterium abundances. The characteristics of the models have been discussed in detail and compared with other work in the literature. The main uncertainties affecting theoretical predictions have been critically discussed. Comparisons with selected data indicate that there is close agreement between theory and observation. Tracks and isochrones are available on the web at the http://astro.df.unipi.it/stellar-models/Tracks and isochrones are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A109

Electronic energy loss of the latent track in heavy ion-irradiated polyimide

International Nuclear Information System (INIS)

Sun Youmei; Liu Jie; Zhang Chonghong; Wang Zhiguang; Jin Yunfan; Duan Jinglai; Song Yin

2005-01-01

In the interaction process of a swift heavy ion (SHI) and polymer, a latent track with radius of several nanometers appears near the ion trajectory due to the dense ionization and excitation. To describe the role of electronic energy loss (dE/dX) e , multi-layer stacks (with different dE/dX) of polyimide (PI) films were irradiated by different SHIs (1.158 GeV Fe 56 and 1.755 GeV Xe 136 ) under vacuum at room temperature. Chemical changes of modified PI films were studied by Fourier Transform Infrared (FTIR) spectroscopy. The main feature of SHI irradiation is the degradation of the functional group and creation of alkyne. The chain disruption rate of PI was investigated in the fluence range from 1 x 10 11 to 6 x 10 12 ions/cm 2 and a wider energy stopping power range (2.2 to 5.2 keV/nm for Fe 56 ions and 8.6 to 11.3 keV/nm for Xe 136 ions). Alkyne formation was observed over the electronic energy loss range of interest. Assuming the saturated track model (the damage process only occur in a cylinder of area σ), the mean degradation and alkyne formation radii in tracks were deduced for Fe and Xe ion irradiation, respectively. The results were validated by the thermal spike model and the threshold electronic energy loss of track formation S et in PI was deduced. The analysis of the irradiated PI films shows that the predictions of the thermal spike model are in qualitative agreement with the curve shape of experimental results. (authors)

On the application of solid state nuclear track detectors (SSNTD)

International Nuclear Information System (INIS)

Almasi, G.

1983-01-01

The thesis presented deals with theoretical and technical aspects of the use of SSNTDs for the registration of charged particles. For thin SSNTD relations between the geometrical parameters of the etch tracks, the etch rate ratio and the etched-off thickness are given which together with calculations on the particle range versus energy make an identification of the particles with respect to their energy as well as their nature possible. For the purpose of the measurement of Radon and α-emitting Radon daughters in living rooms the geometry of the cups has been optimized. The calibration factors have been calculated and verified experimentally. For the evaluation of the track density of thin SSNTD a conductance cell has been set up. Radon concentrations and equilibrium factors were measured over a period of half a year in rooms made of concrete, wood and bricks having identical geometrical dimensions and ventilation rates. The results obtained are discussed briefly. In a long series of experiments which showed the important role of the electroforetic forces involved the 'sequential electrical and chemical etching' technique proposed first by Tommasino and coworkers in 1979 was modified. By means of an optimized choice of the electrolytic solutions the development time could be reduced from about two weeks to two to three hours. Therefore this technique seems to be a useful method to obtain enlarged etch tracks without background interference. (Author)

Design and Performance Evaluation on Ultra-Wideband Time-Of-Arrival 3D Tracking System

Science.gov (United States)

Ni, Jianjun; Arndt, Dickey; Ngo, Phong; Dusl, John

2012-01-01

A three-dimensional (3D) Ultra-Wideband (UWB) Time--of-Arrival (TOA) tracking system has been studied at NASA Johnson Space Center (JSC) to provide the tracking capability inside the International Space Station (ISS) modules for various applications. One of applications is to locate and report the location where crew experienced possible high level of carbon-dioxide and felt upset. In order to accurately locate those places in a multipath intensive environment like ISS modules, it requires a robust real-time location system (RTLS) which can provide the required accuracy and update rate. A 3D UWB TOA tracking system with two-way ranging has been proposed and studied. The designed system will be tested in the Wireless Habitat Testbed which simulates the ISS module environment. In this presentation, we discuss the 3D TOA tracking algorithm and the performance evaluation based on different tracking baseline configurations. The simulation results show that two configurations of the tracking baseline are feasible. With 100 picoseconds standard deviation (STD) of TOA estimates, the average tracking error 0.2392 feet (about 7 centimeters) can be achieved for configuration Twisted Rectangle while the average tracking error 0.9183 feet (about 28 centimeters) can be achieved for configuration Slightly-Twisted Top Rectangle . The tracking accuracy can be further improved with the improvement of the STD of TOA estimates. With 10 picoseconds STD of TOA estimates, the average tracking error 0.0239 feet (less than 1 centimeter) can be achieved for configuration "Twisted Rectangle".

Large Radius Tracking at the ATLAS Experiment

CERN Document Server

Lutz, Margaret Susan; The ATLAS collaboration

2017-01-01

Many exotics and SUSY models include particles which are long lived resulting in decays which are highly displaced from the proton-proton interaction point (IP). The standard track reconstruction algorithm used by the ATLAS collaboration is optimized for tracks from “primary” particles, which originate close to the IP. Thus, tight restrictions on the transverse and longitudinal impact parameters, as well as on several other tracking variables, are applied to improve the track reconstruction performance and to reduce the fake rate. This track reconstruction is very efficient for primary particles, but not for the non-prompt particles mentioned above.  In order to reconstruct tracks with large impact parameters due to displaced decays, a tracking algorithm has been optimized to re-run with loosened requirements over the hits left over after standard track reconstruction has finished. Enabling this “retracking” has significantly increased the efficiency of reconstructing tracks from displaced decays, wh...

Fission track dating evidence on tectonic activities of northern Himalaya block

International Nuclear Information System (INIS)

Yuan Wanming; Wang Shicheng; Wang Lanfen

2002-01-01

Fission track ages (FTA) of 4 apatite samples collected from Langkazi to Yarlung Zangbo thrust zone range between 13.6 and 17.2 Ma, reflecting the time of continent-continent collision and differing from previous data. The negative correlation between the FTA and sample elevations shows there was rapid uplifting during the continent-continent collision with uplifting rate of 176 m/Ma. Denudation degree, denudation rate and cooling rate were ∼2.9 km, 213 m/Ma and 7 degree C/Ma respectively since 13.6 Ma. FTA of 3 zircon samples are different significantly and have x 2 test value of < 0.1%, confirming the orogeny within continent went under low temperature

High-speed tracking control of piezoelectric actuators using an ellipse-based hysteresis model.

Science.gov (United States)

Gu, Guoying; Zhu, Limin

2010-08-01

In this paper, an ellipse-based mathematic model is developed to characterize the rate-dependent hysteresis in piezoelectric actuators. Based on the proposed model, an expanded input space is constructed to describe the multivalued hysteresis function H[u](t) by a multiple input single output (MISO) mapping Gamma:R(2)-->R. Subsequently, the inverse MISO mapping Gamma(-1)(H[u](t),H[u](t);u(t)) is proposed for real-time hysteresis compensation. In controller design, a hybrid control strategy combining a model-based feedforward controller and a proportional integral differential (PID) feedback loop is used for high-accuracy and high-speed tracking control of piezoelectric actuators. The real-time feedforward controller is developed to cancel the rate-dependent hysteresis based on the inverse hysteresis model, while the PID controller is used to compensate for the creep, modeling errors, and parameter uncertainties. Finally, experiments with and without hysteresis compensation are conducted and the experimental results are compared. The experimental results show that the hysteresis compensation in the feedforward path can reduce the hysteresis-caused error by up to 88% and the tracking performance of the hybrid controller is greatly improved in high-speed tracking control applications, e.g., the root-mean-square tracking error is reduced to only 0.34% of the displacement range under the input frequency of 100 Hz.

Reaction rate constants of HO2 + O3 in the temperature range 233-400 K

Science.gov (United States)

Wang, Xiuyan; Suto, Masako; Lee, L. C.

1988-01-01

The reaction rate constants of HO2 + O3 were measured in the temperature range 233-400 K using a discharge flow system with photofragment emission detection. In the range 233-253 K, the constants are approximately a constant value, and then increase with increasing temperature. This result suggests that the reaction may have two different channels. An expression representing the reaction rate constants is presented.

Multi-objective control of nonlinear boiler-turbine dynamics with actuator magnitude and rate constraints.

Science.gov (United States)

Chen, Pang-Chia

2013-01-01

This paper investigates multi-objective controller design approaches for nonlinear boiler-turbine dynamics subject to actuator magnitude and rate constraints. System nonlinearity is handled by a suitable linear parameter varying system representation with drum pressure as the system varying parameter. Variation of the drum pressure is represented by suitable norm-bounded uncertainty and affine dependence on system matrices. Based on linear matrix inequality algorithms, the magnitude and rate constraints on the actuator and the deviations of fluid density and water level are formulated while the tracking abilities on the drum pressure and power output are optimized. Variation ranges of drum pressure and magnitude tracking commands are used as controller design parameters, determined according to the boiler-turbine's operation range. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

A GEM-TPC in twin configuration for the Super-FRS tracking of heavy ions at FAIR

Science.gov (United States)

García, F.; Grahn, T.; Hoffmann, J.; Jokinen, A.; Kaya, C.; Kunkel, J.; Rinta-Antila, S.; Risch, H.; Rusanov, I.; Schmidt, C. J.; Simon, H.; Simons, C.; Turpeinen, R.; Voss, B.; Äystö, J.; Winkler, M.

2018-03-01

The GEM-TPC described herein will be part of the standard beam-diagnostics equipment of the Super-FRS. This chamber will provide tracking information for particle identification at rates up to 1 MHz on an event-by-event basis. The key requirements of operation for these chambers are: close to 100% tracking efficiency under conditions of high counting rate, spatial resolution below 1 mm and a superb large dynamic range covering projectiles from Z = 1 up to Z = 92. The current prototype consists of two GEM-TPCs inside a single vessel, which are operating independently and have electrical drift fields in opposite directions. The twin configuration is done by flipping one of the GEM-TPCs on the middle plane with respect to the second one. In order to put this development in context, the evolution of previous prototypes will be described and its performances discussed. Finally, this chamber was tested at the University of Jyväskylä accelerator with proton projectiles and at GSI with Uranium, Xenon, fragments and Carbon beams. The results obtained have shown a position resolution between 120 to 300 μm at moderate counting rate under conditions of full tracking efficiency.

Trigger tracking for the LHCb upgrade

CERN Multimedia

Dungs, K

2014-01-01

This poster presents a trigger system for the upgraded LHCb detector, scheduled to begin operation in 2020. The proposed trigger system is implemented entirely in software. We show that track reconstruction of a similar quality to that available in the offline algorithms can be performed on the full inelastic pp-collision rate. A track finding efficiency of 98.8% relative to offline can be achieved for good trigger tracks. The CPU time required for this reconstruction is less than 60% of the available budget.

High-q microring resonator with narrow free spectral range for pulse repetition rate multiplication

DEFF Research Database (Denmark)

Pu, Minhao; Ji, Hua; Frandsen, Lars Hagedorn

2009-01-01

We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz.......We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz....

Measurement of bulk etch rates for poly-allyl-diglycol carbonate (PADC) and cellulose nitrate in a broad range of concentration and temperature of NaOH etching solution

International Nuclear Information System (INIS)

Hermsdorf, D.; Hunger, M.; Starke, S.; Weickert, F.

2007-01-01

In the present work the dependence of the bulk etch rate v B for solid state nuclear track detectors (SSNTD) on the concentration c and the temperature T of the NaOH etching solution has been studied for material types PADC and cellulose nitrate. As commonly applied exponents of PADC and cellulose nitrate material, the commercial products CR-39 and LR-115 were investigated. The concentration and temperature have been varied in the ranges 0.5moll -1 -1 and 313 -1 and T between 313 and 333K for cellulose nitrate, respectively. The application of a simple Arrhenius-law of chemical reactions fails in the interpretation of the dependence on the concentration. A constant activation energy cannot describe the behaviour of v B (c,T) over the whole range of concentration. To understand the deviation, more qualified models treating the superposition of chemical and physical processes including reaction kinetics and material transport phenomena by diffusion have to be developed and tested

Kalman filters for real-time magnetic island phase tracking

International Nuclear Information System (INIS)

Borgers, D.P.; Lauret, M.; Baar, M.R. de

2013-01-01

Highlights: • We propose two Kalman filters for tracking of NTMs on ASDEX Upgrade. • The Kalman filters can track NTMs in a much larger frequency range than PLLs. • The filters are tested on synthetic and experimental data from TEXTOR and TCV. • We conclude that the unscented Kalman filter can be useful for NTM control. -- Abstract: For control of neoclassical tearing modes (NTMs) and the resulting rotating magnetic islands in tokamak plasmas, the frequency and phase of the magnetic islands need to be accurately tracked in real-time. In previous experiments on TEXTOR, this was achieved using a phase-locked loop (PLL). For ASDEX Upgrade however, the desired frequency range in which the islands are to be tracked (100 Hz–10 kHz) is much larger than is possible with a PLL. In this contribution, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are proposed for real-time frequency, phase and amplitude tracking of sinusoidal signals, based on noisy measurements. Compared to PLLs, the EKF and UKF are able to track sinusoidal signals in a much larger frequency range. The filters are applied on synthetic data and on experimental data from the TEXTOR and TCV tokamaks, from which we conclude that the UKF can be useful for real-time control of magnetic islands on ASDEX Upgrade

Kalman filters for real-time magnetic island phase tracking

Energy Technology Data Exchange (ETDEWEB)

Borgers, D.P. [Hybrid and Networked Systems, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Lauret, M., E-mail: M.Lauret@tue.nl [FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, Nieuwegein (Netherlands); Control Systems Technology, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Baar, M.R. de [FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, Nieuwegein (Netherlands); Control Systems Technology, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2013-11-15

Highlights: • We propose two Kalman filters for tracking of NTMs on ASDEX Upgrade. • The Kalman filters can track NTMs in a much larger frequency range than PLLs. • The filters are tested on synthetic and experimental data from TEXTOR and TCV. • We conclude that the unscented Kalman filter can be useful for NTM control. -- Abstract: For control of neoclassical tearing modes (NTMs) and the resulting rotating magnetic islands in tokamak plasmas, the frequency and phase of the magnetic islands need to be accurately tracked in real-time. In previous experiments on TEXTOR, this was achieved using a phase-locked loop (PLL). For ASDEX Upgrade however, the desired frequency range in which the islands are to be tracked (100 Hz–10 kHz) is much larger than is possible with a PLL. In this contribution, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are proposed for real-time frequency, phase and amplitude tracking of sinusoidal signals, based on noisy measurements. Compared to PLLs, the EKF and UKF are able to track sinusoidal signals in a much larger frequency range. The filters are applied on synthetic data and on experimental data from the TEXTOR and TCV tokamaks, from which we conclude that the UKF can be useful for real-time control of magnetic islands on ASDEX Upgrade.

Microscopic hydrodynamics study with nuclear track membrane

International Nuclear Information System (INIS)

Shilun Guo; Yuhua Zhao; Yulan Wang; Hiuhong Hao; Brandt, R.; Vater, P.

1988-01-01

Microscopic hydrodynamics has been studied using different liquids and nuclear track membranes with pores perpendicularly piercing through them. The flow rate of water and alcohol has been studied with polycarbonate track membranes with pore diameters 1.48 micrometres and 1.08 micrometres. It has been shown that the flow rate both for water and alcohol on a microscopic scale can be determined by the Poiseuille law which characterizes macroscopic laminar flow. The Reynolds number used in macroscopic fluid flow has been calculated from the flow rate and parameters of the liquids and the geometry of the pores. It has been shown that this Reynolds number can also be used to characterize microscopic flow. Based on the above results, the filtration capacity (or limit) of polycarbonate track microfilters for water had been calculated. Some possible limits on the application of the calculation are pointed out and discussed. (author)

Tracking Residents Through Multiple Residency Programs: A Different Approach for Measuring Residents' Rates of Continuing Graduate Medical Education in ACGME-Accredited Programs.

Science.gov (United States)

Byrne, Lauren M; Holt, Kathleen D; Richter, Thomas; Miller, Rebecca S; Nasca, Thomas J

2010-12-01

Increased focus on the number and type of physicians delivering health care in the United States necessitates a better understanding of changes in graduate medical education (GME). Data collected by the Accreditation Council for Graduate Medical Education (ACGME) allow longitudinal tracking of residents, revealing the number and type of residents who continue GME following completion of an initial residency. We examined trends in the percent of graduates pursuing additional clinical education following graduation from ACGME-accredited pipeline specialty programs (specialties leading to initial board certification). Using data collected annually by the ACGME, we tracked residents graduating from ACGME-accredited pipeline specialty programs between academic year (AY) 2002-2003 and AY 2006-2007 and those pursuing additional ACGME-accredited training within 2 years. We examined changes in the number of graduates and the percent of graduates continuing GME by specialty, by type of medical school, and overall. The number of pipeline specialty graduates increased by 1171 (5.3%) between AY 2002-2003 and AY 2006-2007. During the same period, the number of graduates pursuing additional GME increased by 1059 (16.7%). The overall rate of continuing GME increased each year, from 28.5% (6331/22229) in AY 2002-2003 to 31.6% (7390/23400) in AY 2006-2007. Rates differed by specialty and for US medical school graduates (26.4% [3896/14752] in AY 2002-2003 to 31.6% [4718/14941] in AY 2006-2007) versus international medical graduates (35.2% [2118/6023] to 33.8% [2246/6647]). The number of graduates and the rate of continuing GME increased from AY 2002-2003 to AY 2006-2007. Our findings show a recent increase in the rate of continued training for US medical school graduates compared to international medical graduates. Our results differ from previously reported rates of subspecialization in the literature. Tracking individual residents through residency and fellowship programs provides

Cross-Device Tracking: Measurement and Disclosures

Directory of Open Access Journals (Sweden)

Brookman Justin

2017-04-01

Full Text Available Internet advertising and analytics technology companies are increasingly trying to find ways to link behavior across the various devices consumers own. This cross-device tracking can provide a more complete view into a consumer’s behavior and can be valuable for a range of purposes, including ad targeting, research, and conversion attribution. However, consumers may not be aware of how and how often their behavior is tracked across different devices. We designed this study to try to assess what information about cross-device tracking (including data flows and policy disclosures is observable from the perspective of the end user. Our paper demonstrates how data that is routinely collected and shared online could be used by online third parties to track consumers across devices.

Nanometer-scale anatomy of entire Stardust tracks

Science.gov (United States)

Nakamura-Messenger, Keiko; Keller, Lindsay P.; Clemett, Simon J.; Messenger, Scott; Ito, Motoo

2011-07-01

We have developed new sample preparation and analytical techniques tailored for entire aerogel tracks of Wild 2 sample analyses both on "carrot" and "bulbous" tracks. We have successfully ultramicrotomed an entire track along its axis while preserving its original shape. This innovation allowed us to examine the distribution of fragments along the entire track from the entrance hole all the way to the terminal particle. The crystalline silicates we measured have Mg-rich compositions and O isotopic compositions in the range of meteoritic materials, implying that they originated in the inner solar system. The terminal particle of the carrot track is a 16O-rich forsteritic grain that may have formed in a similar environment as Ca-, Al-rich inclusions and amoeboid olivine aggregates in primitive carbonaceous chondrites. The track also contains submicron-sized diamond grains likely formed in the solar system. Complex aromatic hydrocarbons distributed along aerogel tracks and in terminal particles. These organics are likely cometary but affected by shock heating.

Bilateral simultaneous total hip arthroplasty in a fast track setting

DEFF Research Database (Denmark)

Otte, Kristian S; Husted, Henrik; Ørsnes, Thue

2011-01-01

and low complication rates when performed in a fast-track setting. We believed it would be useful to assess hip arthroplasty in this context, and we report 50 consecutive fast-track simultaneous bilateral hip arthroplasty procedures. The median length of stay was 4 days. Mortality within 90 days was 4......% and 8% required a further operative procedure. The overall complication rate was 22%. 55% of the complications were considered to be caused by failures in surgical technique and 45% by other factors. Bilateral simultaneous hip arthroplasty may have a high complication rate in a fast-track setting...

Optimal Dynamic Strategies for Index Tracking and Algorithmic Trading

Science.gov (United States)

Ward, Brian

In this thesis we study dynamic strategies for index tracking and algorithmic trading. Tracking problems have become ever more important in Financial Engineering as investors seek to precisely control their portfolio risks and exposures over different time horizons. This thesis analyzes various tracking problems and elucidates the tracking errors and strategies one can employ to minimize those errors and maximize profit. In Chapters 2 and 3, we study the empirical tracking properties of exchange traded funds (ETFs), leveraged ETFs (LETFs), and futures products related to spot gold and the Chicago Board Option Exchange (CBOE) Volatility Index (VIX), respectively. These two markets provide interesting and differing examples for understanding index tracking. We find that static strategies work well in the nonleveraged case for gold, but fail to track well in the corresponding leveraged case. For VIX, tracking via neither ETFs, nor futures\\ portfolios succeeds, even in the nonleveraged case. This motivates the need for dynamic strategies, some of which we construct in these two chapters and further expand on in Chapter 4. There, we analyze a framework for index tracking and risk exposure control through financial derivatives. We derive a tracking condition that restricts our exposure choices and also define a slippage process that characterizes the deviations from the index over longer horizons. The framework is applied to a number of models, for example, Black Scholes model and Heston model for equity index tracking, as well as the Square Root (SQR) model and the Concatenated Square Root (CSQR) model for VIX tracking. By specifying how each of these models fall into our framework, we are able to understand the tracking errors in each of these models. Finally, Chapter 5 analyzes a tracking problem of a different kind that arises in algorithmic trading: schedule following for optimal execution. We formulate and solve a stochastic control problem to obtain the optimal

Artificial ion tracks in volcanic dark mica simulating natural radiation damage: A scanning force microscopy study

International Nuclear Information System (INIS)

Lang, M.; Glasmacher, U.A.; Moine, B.; Mueller, C.; Neumann, R.; Wagner, G.A.

2002-01-01

A new dating technique uses alpha-recoil tracks (ART), formed by the natural α-decay of U, Th and their daughter products, to determine the formation age of Quaternary volcanic rocks ( 6 a). Visualization of etched ART by scanning force microscopy (SFM) enables to access track densities beyond 10 8 cm -2 and thus extend the new ART-dating technique to an age range >10 6 a. In order to simulate natural radiation damage, samples of phlogopite, originating from Quaternary and Tertiary volcanic rocks of the Eifel (Germany) and Kerguelen Islands (Indian Ocean) were irradiated with U, Ni (11.4 MeV/u), Xe, Cr, Ne (1.4 MeV/u) and Bi (200 keV) ions. After irradiation and etching with HF at various etching times, phlogopite surfaces were visualized by SFM. Hexagonal etch pits are typical of U, Xe and Cr ion tracks, but the etch pits of Ni, Ne and Bi ion tracks are triangular. Surfaces irradiated with U, Xe, Cr and Ni ions do not show any significant difference between etch pit density and irradiation fluence, whereas the Ne-irradiated surface show ∼14 times less etch pit density. The etching rate v H (parallel to cleavage) depends on the chemical composition of the phlogopite. The etching rate v T ' (along the track) increases with energy loss

Stability of narcissistic personality disorder: tracking categorical and dimensional rating systems over a two-year period.

Science.gov (United States)

Vater, Aline; Ritter, Kathrin; Strunz, Sandra; Ronningstam, Elsa F; Renneberg, Babette; Roepke, Stefan

2014-07-01

Personality disorders are characterized as temporally stable patterns of symptoms (APA, 2000). However, evidence on the stability of narcissistic personality disorder (NPD) is generally lacking. This study tracked the prevalence and remission rates of individual criteria for NPD over the course of 2 years. In addition, the stability of dimensional personality pathology in patients with NPD (assessed with the Dimensional Assessment of Personality Pathology, DAPP-BQ) was assessed over time. A sample of 96 patients with a diagnosis of NPD was recruited at baseline. Forty patients participated in the follow-up assessment 2 years later. Our results indicate a moderate remission rate (53%) for NPD as a categorical diagnosis. However, single NPD criteria differed in their prevalence and temporal stability, similar to findings for other personality disorders. Moreover, scores on dimensional subscales of the DAPP-BQ remained stable over time. Theoretical implications are discussed. (c) 2014 APA, all rights reserved.

ATLAS Fast Tracker Status and Tracking at High luminosity LHC

CERN Document Server

Ilic, Nikolina; The ATLAS collaboration

2018-01-01

The LHC’s increase in centre of mass energy and luminosity in 2015 makes controlling trigger rates with high efficiency challenging. The ATLAS Fast TracKer (FTK) is a hardware processor built to reconstruct tracks at a rate of up to 100 kHz and provide them to the high level trigger. The FTK reconstructs tracks by matching incoming detector hits with pre-defined track patterns stored in associative memory on custom ASICs. Inner detector hits are fit to these track patterns using modern FPGAs. This talk describes the electronics system used for the FTK’s massive parallelization. The installation, commissioning and running of the system is happening in 2016, and is detailed in this talk. Tracking at High luminosity LHC is also presented.

Maximum power point tracking

International Nuclear Information System (INIS)

Enslin, J.H.R.

1990-01-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

Observations on the geometries of etched fission and alpha-recoil tracks with reference to models of track revelation in minerals

International Nuclear Information System (INIS)

Jonckheere, R.; Enkelmann, E.; Stuebner, K.

2005-01-01

The kinetic and atomistic theories of crystal growth and dissolution are used to interpret the shapes and orientations of fission-track, recoil-track and dislocation etch pits in tri-octahedral phlogopite and di-octahedral muscovite. An atomistic approach combined with symmetry considerations lead to the identification of the periodic bond chains that determine the etch pit morphologies and relative etch rates at a chemical level: O-Mg-O in phlogopite, O-Mg-O-Fe in biotite and O-Al-O in muscovite. Using first-order estimates of the bond strengths, it is possible to account for the relative track etch rates in these minerals. The reported, sometimes simultaneous, occurrence of triangular, polygonal and hexagonal etch pit contours in phlogopite, some of which violate the crystal symmetry, suggests that the cohesion of the phlogopite lattice is lost over a much larger radius than that of the track core around the trajectories of particles for which the energy loss exceeds a threshold value. This is interpreted as an indication of pronounced sublattice and anisotropic effects during track registration

An 'artificial retina' processor for track reconstruction at the full LHC crossing rate

OpenAIRE

Abba, A; Bedeschi, F; Caponio, F; Cenci, R; Citterio, M; Cusimano, A; Fu, J; Geraci, A; Grizzuti, M; Lusardi, N; Marino, P; Morello, M J; Neri, N; Ninci, D; Petruzzo, M

2016-01-01

We present the latest results of an R&D; study for a specialized processor capable of reconstructing, in a silicon pixel detector, high-quality tracks from high-energy collision events at 40 MHz. The processor applies a highly parallel pattern-recognition algorithm inspired to quick detection of edges in mammals visual cortex. After a detailed study of a real-detector application, demonstrating that online reconstruction of offline-quality tracks is feasible at 40 MHz with sub-microsecond lat...

Modelling plastic deformation of metals over a wide range of strain rates using irreversible thermodynamics

International Nuclear Information System (INIS)

Huang Mingxin; Rivera-Diaz-del-Castillo, Pedro E J; Zwaag, Sybrand van der; Bouaziz, Olivier

2009-01-01

Based on the theory of irreversible thermodynamics, the present work proposes a dislocation-based model to describe the plastic deformation of FCC metals over wide ranges of strain rates. The stress-strain behaviour and the evolution of the average dislocation density are derived. It is found that there is a transitional strain rate (∼ 10 4 s -1 ) over which the phonon drag effects appear, resulting in a significant increase in the flow stress and the average dislocation density. The model is applied to pure Cu deformed at room temperature and at strain rates ranging from 10 -5 to 10 6 s -1 showing good agreement with experimental results.

Multitarget tracking in cluttered environment for a multistatic passive radar system under the DAB/DVB network

Science.gov (United States)

Shi, Yi Fang; Park, Seung Hyo; Song, Taek Lyul

2017-12-01

The target tracking using multistatic passive radar in a digital audio/video broadcast (DAB/DVB) network with illuminators of opportunity faces two main challenges: the first challenge is that one has to solve the measurement-to-illuminator association ambiguity in addition to the conventional association ambiguity between the measurements and targets, which introduces a significantly complex three-dimensional (3-D) data association problem among the target-measurement illuminator, this is because all the illuminators transmit the same carrier frequency signals and signals transmitted by different illuminators but reflected via the same target become indistinguishable; the other challenge is that only the bistatic range and range-rate measurements are available while the angle information is unavailable or of very poor quality. In this paper, the authors propose a new target tracking algorithm directly in three-dimensional (3-D) Cartesian coordinates with the capability of track management using the probability of target existence as a track quality measure. The proposed algorithm is termed sequential processing-joint integrated probabilistic data association (SP-JIPDA), which applies the modified sequential processing technique to resolve the additional association ambiguity between measurements and illuminators. The SP-JIPDA algorithm sequentially operates the JIPDA tracker to update each track for each illuminator with all the measurements in the common measurement set at each time. For reasons of fair comparison, the existing modified joint probabilistic data association (MJPDA) algorithm that addresses the 3-D data association problem via "supertargets" using gate grouping and provides tracks directly in 3-D Cartesian coordinates, is enhanced by incorporating the probability of target existence as an effective track quality measure for track management. Both algorithms deal with nonlinear observations using the extended Kalman filtering. A simulation study is

Maximum-power-point tracking control of solar heating system

KAUST Repository

Huang, Bin-Juine

2012-11-01

The present study developed a maximum-power point tracking control (MPPT) technology for solar heating system to minimize the pumping power consumption at an optimal heat collection. The net solar energy gain Q net (=Q s-W p/η e) was experimentally found to be the cost function for MPPT with maximum point. The feedback tracking control system was developed to track the optimal Q net (denoted Q max). A tracking filter which was derived from the thermal analytical model of the solar heating system was used to determine the instantaneous tracking target Q max(t). The system transfer-function model of solar heating system was also derived experimentally using a step response test and used in the design of tracking feedback control system. The PI controller was designed for a tracking target Q max(t) with a quadratic time function. The MPPT control system was implemented using a microprocessor-based controller and the test results show good tracking performance with small tracking errors. It is seen that the average mass flow rate for the specific test periods in five different days is between 18.1 and 22.9kg/min with average pumping power between 77 and 140W, which is greatly reduced as compared to the standard flow rate at 31kg/min and pumping power 450W which is based on the flow rate 0.02kg/sm 2 defined in the ANSI/ASHRAE 93-1986 Standard and the total collector area 25.9m 2. The average net solar heat collected Q net is between 8.62 and 14.1kW depending on weather condition. The MPPT control of solar heating system has been verified to be able to minimize the pumping energy consumption with optimal solar heat collection. © 2012 Elsevier Ltd.

Optical efficiency for fission fragment track counting in Muscovite solid state track recorders

International Nuclear Information System (INIS)

Roberts, J.H.; Ruddy, F.H.; Gold, R.

1984-01-01

In order to determine absolute fission rates from thin actinide deposits placed in direct contact with Muscovite Solid State Track Recorders, it is necessary to know the efficiency with which fission fragment tracks are recorded. In this paper, a redetermination of the 'optical efficiency', i.e. the fraction of fission events recorded and observed in the Muscovite is reported. The value obtained from a well-calibrated thin deposit of 252 Cf and Muscovite etched about 90 min. in 49% HF at room temperature, is 0.9875 +- 0.0085. Manual counting was used. Preliminary results from a deposit of 242 Pu are also reported, along with preliminary comparisons of track counting with an automated system. Reasons for the discrepancy of the optical efficiency reported here with an earlier measurement are also reported. (author)

The Timepix Telescope for High Performance Particle Tracking

CERN Document Server

Akiba, Kazuyoshi; van Beuzekom, Martin; van Beveren, Vincent; Borghi, Silvia; Boterenbrood, Henk; Buytaert, Jan; Collins, Paula; Dosil Suárez, Alvaro; Dumps, Raphael; Eklund, Lars; Esperante, Daniel; Gallas, Abraham; Gordon, Hamish; van der Heijden, Bas; Hombach, Christoph; Hynds, Daniel; John, Malcolm; Leflat, Alexander; Li, Yi Ming; Longstaff, Ian; Morton, Alexander; Nakatsuka, Noritsugu; Nomerotski, Andre; Parkes, Chris; Perez Trigo, Eliseo; Plackett, Richard; Reid, Matthew M; Rodriguez Perez, Pablo; Schindler, Heinrich; Szumlak, Tomasz; Tsopelas, Panagiotis; Vázquez Sierra, Carlos; Velthuis, Jaap; Wysokinski, Michal

2013-01-01

The Timepix particle tracking telescope has been developed as part of the LHCb VELO Upgrade project, supported by the Medipix Collaboration and the AIDA framework. It is a primary piece of infrastructure for the VELO Upgrade project and is being used for the development of new sensors and front end technologies for several upcoming LHC trackers and vertexing systems. The telescope is designed around the dual capability of the Timepix ASICs to provide information about either the deposited charge or the timing information from tracks traversing the 14 x 14mm matrix of 55 x 55 um pixels. The rate of reconstructed tracks available is optimised by taking advantage of the shutter driven readout architecture of the Timepix chip, operated with existing readout systems. Results of tests conducted in the SPS North Area beam facility at CERN show that the telescope typically provides reconstructed track rates during the beam spills of between 3.5 and 7.5 kHz, depending on beam conditions. The tracks are time stamped wi...

Tracking Subpixel Targets with Critically Sampled Optical Sensors

Science.gov (United States)

2012-09-01

LEFT BLANK xii LIST OF ACRONYMS AND ABBREVIATIONS PSF point spread function SNR signal-to-noise ratio SLAM simultaneous localization and tracking EO... LIDAR light detection and ranging FOV field of view RMS root mean squared PF particle filter TBD track before detect MCMC monte carlo markov chain

High-speed particle tracking in microscopy using SPAD image sensors

Science.gov (United States)

Gyongy, Istvan; Davies, Amy; Miguelez Crespo, Allende; Green, Andrew; Dutton, Neale A. W.; Duncan, Rory R.; Rickman, Colin; Henderson, Robert K.; Dalgarno, Paul A.

2018-02-01

Single photon avalanche diodes (SPADs) are used in a wide range of applications, from fluorescence lifetime imaging microscopy (FLIM) to time-of-flight (ToF) 3D imaging. SPAD arrays are becoming increasingly established, combining the unique properties of SPADs with widefield camera configurations. Traditionally, the photosensitive area (fill factor) of SPAD arrays has been limited by the in-pixel digital electronics. However, recent designs have demonstrated that by replacing the complex digital pixel logic with simple binary pixels and external frame summation, the fill factor can be increased considerably. A significant advantage of such binary SPAD arrays is the high frame rates offered by the sensors (>100kFPS), which opens up new possibilities for capturing ultra-fast temporal dynamics in, for example, life science cellular imaging. In this work we consider the use of novel binary SPAD arrays in high-speed particle tracking in microscopy. We demonstrate the tracking of fluorescent microspheres undergoing Brownian motion, and in intra-cellular vesicle dynamics, at high frame rates. We thereby show how binary SPAD arrays can offer an important advance in live cell imaging in such fields as intercellular communication, cell trafficking and cell signaling.

An artificial retina for fast track finding

International Nuclear Information System (INIS)

Ristori, Luciano

2000-01-01

A new approach is proposed for fast track finding in position-sensitive detectors. The basic working principle is modeled on what is widely believed to be the low-level mechanism used by the eye to recognize straight edges. A number of receptors are tuned such that each one responds to a different range of track orientations, each track actually fires several receptors and an estimate of the orientation is obtained through interpolation. The feasibility of a practical device based on this principle and its possible implementation using currently available digital logic is discussed

Robust Real-Time Tracking for Visual Surveillance

Directory of Open Access Journals (Sweden)

Aguilera Josep

2007-01-01

Full Text Available This paper describes a real-time multi-camera surveillance system that can be applied to a range of application domains. This integrated system is designed to observe crowded scenes and has mechanisms to improve tracking of objects that are in close proximity. The four component modules described in this paper are (i motion detection using a layered background model, (ii object tracking based on local appearance, (iii hierarchical object recognition, and (iv fused multisensor object tracking using multiple features and geometric constraints. This integrated approach to complex scene tracking is validated against a number of representative real-world scenarios to show that robust, real-time analysis can be performed.

Multi-GNSS orbit determination using satellite laser ranging

Science.gov (United States)

Bury, Grzegorz; Sośnica, Krzysztof; Zajdel, Radosław

2018-04-01

Galileo, BeiDou, QZSS, and NavIC are emerging global navigation satellite systems (GNSSs) and regional navigation satellite systems all of which are equipped with laser retroreflector arrays for range measurements. This paper summarizes the GNSS-intensive tracking campaigns conducted by the International Laser Ranging Service and provides results from multi-GNSS orbit determination using solely SLR observations. We consider the whole constellation of GLONASS, all active Galileo, four BeiDou satellites: 1 MEO, 3 IGSO, and one QZSS. We analyze the influence of the number of SLR observations on the quality of the 3-day multi-GNSS orbit solution. About 60 SLR observations are needed for obtaining MEO orbits of sufficient quality with the root mean square (RMS) of 3 cm for the radial component when compared to microwave-based orbits. From the analysis of a minimum number of tracking stations, when considering the 3-day arcs, 5 SLR stations do not provide a sufficient geometry of observations. The solution obtained using ten stations is characterized with RMS of 4, 9, and 18 cm in the radial, along-track, and cross-track direction, respectively, for MEO satellites. We also investigate the impact of the length of orbital arc on the quality of SLR-derived orbits. Hence, 5- and 7-day arcs constitute the best solution, whereas 3-day arcs are of inferior quality due to an insufficient number of SLR observations and 9-day arcs deteriorate the along-track component. The median RMS from the comparison between 7-day orbital arcs determined using SLR data with microwave-based orbits assumes values in the range of 3-4, 11-16, and 15-27 cm in radial, along-track, and cross-track, respectively, for MEO satellites. BeiDou IGSO and QZSS are characterized by RMS values higher by a factor of 8 and 24, respectively, than MEO orbits.

Annealing behavior of alpha recoil tracks in phlogopite

International Nuclear Information System (INIS)

Gao Shaokai; Yuan Wanming; Dong Jinquan; Bao Zengkuan

2005-01-01

Alpha recoil tracks (ARTs) formed during the a-decay of U, Th as well as their daughter nuclei are used as a new dating method which is to some extent a complementarity of fission track dating due to its ability to determine the age of young mineral. ARTs can be observable under phase-contrast interference microscope through chemical etching. In order to study the annealing behavior of ARTs in phlogopite, two methods of annealing experiments were executed. Samples were annealed in the electronic tube furnace at different temperatures ranging from 250 degree C to 450 degree C in steps of 50 degree C. For any given annealing temperature, different annealing times were used until total track fading were achieved. It is found that ARTs anneal much more easily than fission tracks, the annealing ratio increase non-linearly with annealing time and temperature. Using the Arrhenius plot, an activation energy of 0.68ev is finally found for 100% removal of ARTs, which is less than the corresponding value for fission tracks (FTs). Through extending the annealing time to geological time, a much lower temperature range of the sample's cooling history can be got.

PHENIX central arm tracking detectors

International Nuclear Information System (INIS)

Adcox, K.; Ajitanand, N.N.; Alexander, J.; Autrey, D.; Averbeck, R.; Azmoun, B.; Barish, K.N.; Baublis, V.V.; Belkin, R.; Bhaganatula, S.; Biggs, J.C.; Borland, D.; Botelho, S.; Bryan, W.L.; Burward-Hoy, J.; Butsyk, S.A.; Chang, W.C.; Christ, T.; Dietzsch, O.; Drees, A.; Rietz, R. du; El Chenawi, K.; Evseev, V.A.; Fellenstein, J.; Ferdousi, T.; Fraenkel, Z.; Franz, A.; Fung, S.Y.; Gannon, J.; Garpman, S.; Godoi, A.L.; Greene, S.V.; Gustafsson, H.-A.; Harder, J.; Hemmick, T.K.; Heuser, J.M.; Holzmann, W.; Hutter, R.; Issah, M.; Ivanov, V.I.; Jacak, B.V.; Jagadish, U.; Jia, J.; Johnson, S.C.; Kandasamy, A.; Kann, M.R.; Kelley, M.A.; Khanzadeev, A.V.; Khomutnikov, A.; Komkov, B.G.; Kopytine, M.L.; Kotchenda, L.; Kotchetkov, D.; Kozlov, V.S.; Kravtsov, P.A.; Kudin, L.G.; Kuriatkov, V.V.; Lacey, R.; Lauret, J.; Lebedev, A.; Lebedev, V.D.; Li, X.H.; Libby, B.; Liccardi, W.; Machnowski, R.; Mahon, J.; Markushin, D.G.; Matathias, F.; Marx, M.D.; Messer, F.; Miftakhov, N.M.; Milan, J.; Miller, T.E.; Milov, A.; Minuzzo, K.; Mioduszewski, S.; Mitchell, J.T.; Muniruzzamann, M.; Nandi, B.K.; Negrin, J.; Nilsson, P.; Nystrand, J.; O'Brien, E.; O'Connor, P.; Oskarsson, A.; Oesterman, L.; Otterlund, I.; Pancake, C.E.; Pantuev, V.S.; Petersen, R.; Pinkenburg, C.H.; Pisani, R.P.; Purwar, A.K.; Rankowitz, S.; Ravinovich, I.; Riabov, V.G.; Riabov, Yu.G.; Rosati, M.; Rose, A.A.; Roschin, E.V.; Samsonov, V.M.; Sangster, T.C.; Seto, R.; Silvermyr, D.; Sivertz, M.; Smith, M.; Solodov, G.P.; Stenlund, E.; Takagui, E.M.; Tarakanov, V.I.; Tarasenkova, O.P.; Thomas, J.L.; Trofimov, V.A.; Tserruya, I.; Tydesjoe, H.; Velkovska, J.; Velkovsky, M.; Vishnevskii, V.I.; Vorobyov, A.A.; Vznuzdaev, E.A.; Vznuzdaev, M.; Wang, H.Q.; Weimer, T.; Wolniewicz, K.; Wu, J.; Xie, W.; Young, G.R.

2003-01-01

The PHENIX tracking system consists of Drift Chambers (DC), Pad Chambers (PC) and the Time Expansion Chamber (TEC). PC1/DC and PC2/TEC/PC3 form the inner and outer tracking units, respectively. These units link the track segments that transverse the RICH and extend to the EMCal. The DC measures charged particle trajectories in the r-phi direction to determine p T of the particles and the invariant mass of particle pairs. The PCs perform 3D spatial point measurements for pattern recognition and longitudinal momentum reconstruction and provide spatial resolution of a few mm in both r-phi and z. The TEC tracks particles passing through the region between the RICH and the EMCal. The design and operational parameters of the detectors are presented and running experience during the first year of data taking with PHENIX is discussed. The observed spatial and momentum resolution is given which imposes a limitation on the identification and characterization of charged particles in various momentum ranges

Upgrade of the ALICE Inner Tracking System

OpenAIRE

Reidt, Felix; Collaboration, for the ALICE

2014-01-01

During the Long Shutdown 2 of the LHC in 2018/2019, the ALICE experiment plans the installation of a novel Inner Tracking System. It will replace the current six layer detector system with a seven layer detector using Monolithic Active Pixel Sensors. The upgraded Inner Tracking System will have significantly improved tracking and vertexing capabilities, as well as readout rate to cope with the expected increased Pb-Pb luminosity of the LHC. The choice of Monolithic Active Pixel Sensors has be...

Non-sequential fruit tracking by birds along an altitudinal gradient

Science.gov (United States)

Hasui, Erica; Ramos, Flavio Nunes; Tamashiro, Jorge Yoshio; Silva, Wesley Rodrigues

2012-11-01

Despite landscape-level changes in fruit quantity, food resources may be constantly available to frugivorous animals if they track asynchronous fruit peaks. To investigate fruit availability patterns and their consequences on bird abundance, we tested for the occurrence of seasonal patterns in fruit production at three elevations (range 500-1000 m asl) in the Brazilian Atlantic Forest over three years and compared these patterns among the elevations and years. Fruit production occurred throughout the year and showed only slight seasonality, and only at the two higher elevation sites. Contrary to expectation, fruiting peaks were neither predictable nor complementary. A few plant species (about 5%) contributed disproportionately to the high annual variation of fruit production in plant communities. We found no relationship between fruit production and bird capture rates of both generalist and specialist fruit eating species, suggesting that birds do not track fruit resources along the gradient, at least in some parts of the Atlantic Forest, or in some years. The apparent constancy of fruit availability probably does not stimulate birds to track to other elevations. In addition, plants with high annual variation in fruit production could be influencing and biasing our assessment of this relationship.

Safety of fast track surgery in pancreaticoduodenectomy: a Meta-analysis

Directory of Open Access Journals (Sweden)

LI Weinan

2017-01-01

Full Text Available ObjectiveTo investigate the safety and clinical effect of fast track surgery in pancreaticoduodenectomy, one of the most complex surgeries in general surgery. MethodsThe Chinese and foreign databases were searched for articles on the application of fast tract surgery in pancreaticoduodenectomy published from January 1994 to April 2016. Two researchers evaluated the quality of the articles which met the inclusion criteria and extracted related data. Stata 12.0 software was used to analyze the overall incidence rate of complications and the incidence rates of pancreatic leakage and gastrointestinal emptying disorder, and the Begg rank correlation test and Egger linear regression method were used to investigate publication bias. ResultsThe fast track surgery group had a significantly lower overall incidence rate of complications than the conventional group (RR=0.748, 95%CI: 0.680-0.824, P＜0.001. There was no significant difference in the incidence rate of pancreatic leakage between the two groups (RR=0.894, 95%CI:0.734-1.089, P=0.266. The fast track surgery group had a significantly lower incidence rate of gastrointestinal emptying disorder than the conventional group (RR=0.520, 95%CI:0.400-0.670, P＜0.001. ConclusionFast track surgery is safe and effective in pancreaticoduodenectomy, but the application of some measures in fast track surgery still needs more medical evidence.

Cognitive dysfunction after fast-track hip and knee replacement

DEFF Research Database (Denmark)

Krenk, Lene; Kehlet, Henrik; Bæk Hansen, Torben

2014-01-01

to 2 weeks and 3 months postoperatively. LOS, pain, opioid use, inflammatory response, and sleep quality were recorded. The practice effect of repeated cognitive testing was gauged using data from a healthy community-dwelling control group (n = 161). RESULTS: Median LOS was 2 days (interquartile range...... this (23.6% of patients with early POCD had late onset vs 6.7% in non-POCD group; risk difference 16.9 (95% CI, -2.1% to 41.1%; P = 0.089). CONCLUSIONS: The incidence of POCD early after total hip and knee replacement seems to be lower after a fast-track approach than rates previously reported...

RFID-over-Fiber system for agricultural exploitations - Wireless track and trace with range extension using optical fiber

DEFF Research Database (Denmark)

Madsen, Peter; Suhr, Lau Frejstrup; Cavalcante, Lucas Costa Pereira

2015-01-01

This paper proposes and demonstrates an RFIDover-Fiber wireless track and trace system using active RFID tags and operating over distances up to 30 km of optical fiber and 35 meters of wireless readability......This paper proposes and demonstrates an RFIDover-Fiber wireless track and trace system using active RFID tags and operating over distances up to 30 km of optical fiber and 35 meters of wireless readability...

Critical rate of energy loss for registration of charged particles in cellulose nitrate

International Nuclear Information System (INIS)

Knoefel, T.M.J.; Sachett, I.A.

1979-09-01

Cellulose nitrate films LR-115 type II (Kodak-Pathe) have been exposed, at right angles, to alpha-particle beams in the energy range 2.5 - 5.5 MeV. From measurements of both through etched track density, a critical rate of energy lo ss for track registration of (0.85 +- 0.05) MeV cm 2 /mg has been derived, which corresponds to a critical alpha-particle energy of (4.6 +- 0.4) MeV. These results are compatible with those obtained by other authors whenever similar etching conditions are used. The concepts of threshold rate of energy loss and a threshold energy for etched-track formation are introduced, and their values are obtained from the experiment as being (0.80 +- 0.05) MeV cm 2 /mg and (5.1 +- 0.4) Mev, respectively. In addition, the present work provides a suitable set of useful, reference data for further applications of such plastic nuclear track detector in problems concerned with the detection of low-energy alpha particles. (Author) [pt

An "artificial retina" processor for track reconstruction at the full LHC crossing rate

Science.gov (United States)

Abba, A.; Bedeschi, F.; Caponio, F.; Cenci, R.; Citterio, M.; Cusimano, A.; Fu, J.; Geraci, A.; Grizzuti, M.; Lusardi, N.; Marino, P.; Morello, M. J.; Neri, N.; Ninci, D.; Petruzzo, M.; Piucci, A.; Punzi, G.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.; Walsh, J.

2016-07-01

We present the latest results of an R&D study for a specialized processor capable of reconstructing, in a silicon pixel detector, high-quality tracks from high-energy collision events at 40 MHz. The processor applies a highly parallel pattern-recognition algorithm inspired to quick detection of edges in mammals visual cortex. After a detailed study of a real-detector application, demonstrating that online reconstruction of offline-quality tracks is feasible at 40 MHz with sub-microsecond latency, we are implementing a prototype using common high-bandwidth FPGA devices.

Irradiation effect of different heavy ions and track section on the silkworm Bombyx mori

Energy Technology Data Exchange (ETDEWEB)

Tu Zhenli E-mail: tu514@yahoo.co.jp; Kobayashi, Yasuhiko; Kiguchi, Kenji; Watanabe, Hiroshi

2003-05-01

In order to compare the irradiation effects of different ions, wandering larvae were whole-body exposed or locally irradiated with 50-MeV {sup 4}He{sup 2+}, 220-MeV {sup 12}C{sup 5+}, and 350-MeV {sup 20}Ne{sup 8+} ions, respectively. For the whole-body-exposed individuals, the survival rates at the cocooning, pupation, and emergence stages all decreased as dose increased, and a range-dependent difference was clearly observed. For local irradiation of ovaries, irradiation effects depend very strongly on the projectile range. In the case of local irradiation of dermal cells by different track sections of heavy ions, the closer the target was to the high-LET section of the track, the more pronounced were the radiation effects. These results indicated that by selectively using ion species and adjusting the irradiation depth to the target, heavy-ion radiosurgery on particular tissues or organs of small experimental animals can be performed more accurately.

Irradiation effect of different heavy ions and track section on the silkworm Bombyx mori

International Nuclear Information System (INIS)

Tu Zhenli; Kobayashi, Yasuhiko; Kiguchi, Kenji; Watanabe, Hiroshi

2003-01-01

In order to compare the irradiation effects of different ions, wandering larvae were whole-body exposed or locally irradiated with 50-MeV 4 He 2+ , 220-MeV 12 C 5+ , and 350-MeV 20 Ne 8+ ions, respectively. For the whole-body-exposed individuals, the survival rates at the cocooning, pupation, and emergence stages all decreased as dose increased, and a range-dependent difference was clearly observed. For local irradiation of ovaries, irradiation effects depend very strongly on the projectile range. In the case of local irradiation of dermal cells by different track sections of heavy ions, the closer the target was to the high-LET section of the track, the more pronounced were the radiation effects. These results indicated that by selectively using ion species and adjusting the irradiation depth to the target, heavy-ion radiosurgery on particular tissues or organs of small experimental animals can be performed more accurately

Strain and strain rate by two-dimensional speckle tracking echocardiography in a maned wolf

Directory of Open Access Journals (Sweden)

Matheus M. Mantovani

2012-12-01

Full Text Available The measurement of cardiovascular features of wild animals is important, as is the measurement in pets, for the assessment of myocardial function and the early detection of cardiac abnormalities, which could progress to heart failure. Speckle tracking echocardiography (2D STE is a new tool that has been used in veterinary medicine, which demonstrates several advantages, such as angle independence and the possibility to provide the early diagnosis of myocardial alterations. The aim of this study was to evaluate the left myocardial function in a maned wolf by 2D STE. Thus, the longitudinal, circumferential and radial strain and strain rate were obtained, as well as, the radial and longitudinal velocity and displacement values, from the right parasternal long axis four-chamber view, the left parasternal apical four chamber view and the parasternal short axis at the level of the papillary muscles. The results of the longitudinal variables were -13.52±7.88, -1.60±1.05, 4.34±2.52 and 3.86±3.04 for strain (%, strain rate (1/s, displacement (mm and velocity (cm/s, respectively. In addition, the radial and circumferential Strain and Strain rate were 24.39±14.23, 1.86±0.95 and -13.69±6.53, -1.01±0.48, respectively. Thus, the present study provides the first data regarding the use of this tool in maned wolves, allowing a more complete quantification of myocardial function in this species.

Drop-out rate and drop-out reasons among promising Norwegian track and field athletes: a 25 year study

OpenAIRE

Enoksen, Eystein

2011-01-01

© Eystein Enoksen, 2011 The aim of the present study was to identify the total drop-out rate and drop-out reasons for a group of promising track and field athletes. 202 males and 98 females, aged 16 ±2 years, took part in this study. Questionnaires were administrated in 1975, 1983, and 1989. In-depth interviews were conducted in 1989 and in 2000. A chi-square test was administrated to test the difference between males and females dropping out and to test the most significant reasons influe...

The ATLAS Fast Tracker and Tracking at the High-Luminosity LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00236423; The ATLAS collaboration

2016-01-01

The LHC’s increase in centre of mass energy and luminosity in 2015 makes controlling trigger rates with high efficiency challenging. The ATLAS Fast TracKer (FTK) is a hardware processor built to reconstruct tracks at a rate of up to 100 kHz and provide them to the high level trigger. The FTK reconstructs tracks by matching incoming detector hits with pre-defined track patterns stored in associative memory on custom ASICs. Inner detector hits are fit to these track patterns using modern FPGAs. These procedings describe the electronics system used for the FTK’s massive parallelization. An overview of the installation, commissioning and running of the system is given. The ATLAS upgrades planned to enable tracking at the High Luminosity LHC are also discussed.

Self-tracking optical beam monitor

International Nuclear Information System (INIS)

Miyahara, T.; Mitsuhashi, T.

1992-01-01

A new optical beam monitor with a self-tracking system was constructed and tested at an undulator beam line of the Photon Factory. The monitor has a feedback system to receive a constant part of the radiation and gives a large range of linearity. The beam position is read out through a linear encoder to detect the self-tracking movement of a pair of photocathodes. The monitor except the feedback system is totally bakeable and UHV compatible and can be installed at a VUV or a soft x-ray beam line

Optical efficiency for fission-fragment track counting in Muscovite Solid-State Track Recorders

International Nuclear Information System (INIS)

Roberts, J.H.; Ruddy, F.H.; Gold, R.

1983-07-01

In order to determine absolute fission rates from thin actinide deposits placed in direct contact with Muscovite Solid-State Track Recorders, it is necessary to know the efficiency with which fission-fragment tracks are recorded. In this paper, a redetermination of the optical efficiency, i.e., the fraction of fission events recorded and observed in the Muscovite, is reported. The value obtained from a well-calibrated thin deposit of 252 Cf and Muscovite etched about 90 min. in 49% HF at room temperature, is 0.9875 +- 0.0085. Manual counting was used. Preliminary results from a deposit of 242 Pu are also reported, along with preliminary comparisons of track counting with an automated system. Reasons for the discrepancy of the optical efficiency reported here with an earlier measurement are also reported. 5 references, 1 figure, 3 tables

Automation system for optical counting of nuclear tracks

Energy Technology Data Exchange (ETDEWEB)

Boulyga, S.F.; Boulyga, E.G.; Lomonosova, E.M.; Zhuk, I.V

1999-06-01

An automation system consisting of the microscope, video camera and Pentium PC with frame recorder was created. The system provides counting of nuclear tracks on the SSNTD surface with a resolution of 752 x 582 points, determination of the surface area and main axis of the track. The pattern recognition program was developed for operation in Windows 3.1 (or higher) ensuring a convenient interface with the user. In a comparison of the results on automatic track counting with the more accurate hand mode it was shown that the program enables the tracks to be detected even on images with a rather high noise level. It ensures a high accuracy of track counting being comparable with the accuracy of manual counting for densities of tracks in the range of up to 2{center_dot}10{sup 5} tracks/cm{sup 2}. The automatic system was applied in the experimental investigation of uranium and transuranium elements.

Automation system for optical counting of nuclear tracks

International Nuclear Information System (INIS)

Boulyga, S.F.; Boulyga, E.G.; Lomonosova, E.M.; Zhuk, I.V.

1999-01-01

An automation system consisting of the microscope, video camera and Pentium PC with frame recorder was created. The system provides counting of nuclear tracks on the SSNTD surface with a resolution of 752 x 582 points, determination of the surface area and main axis of the track. The pattern recognition program was developed for operation in Windows 3.1 (or higher) ensuring a convenient interface with the user. In a comparison of the results on automatic track counting with the more accurate hand mode it was shown that the program enables the tracks to be detected even on images with a rather high noise level. It ensures a high accuracy of track counting being comparable with the accuracy of manual counting for densities of tracks in the range of up to 2·10 5 tracks/cm 2 . The automatic system was applied in the experimental investigation of uranium and transuranium elements

Automation system for optical counting of nuclear tracks

CERN Document Server

Boulyga, S F; Lomonosova, E M; Zhuk, I V

1999-01-01

An automation system consisting of the microscope, video camera and Pentium PC with frame recorder was created. The system provides counting of nuclear tracks on the SSNTD surface with a resolution of 752 x 582 points, determination of the surface area and main axis of the track. The pattern recognition program was developed for operation in Windows 3.1 (or higher) ensuring a convenient interface with the user. In a comparison of the results on automatic track counting with the more accurate hand mode it was shown that the program enables the tracks to be detected even on images with a rather high noise level. It ensures a high accuracy of track counting being comparable with the accuracy of manual counting for densities of tracks in the range of up to 2 centre dot 10 sup 5 tracks/cm sup 2. The automatic system was applied in the experimental investigation of uranium and transuranium elements.

FPGA helix tracking algorithm for PANDA

Energy Technology Data Exchange (ETDEWEB)

Liang, Yutie; Galuska, Martin; Gessler, Thomas; Kuehn, Wolfgang; Lange, Jens Soeren; Muenchow, David [II. Physikalisches Institut, University of Giessen (Germany); Ye, Hua [Institute of High Energy Physics, CAS (China); Collaboration: PANDA-Collaboration

2016-07-01

The PANDA detector is a general-purpose detector for physics with high luminosity cooled antiproton beams, planed to operate at the FAIR facility in Darmstadt, Germany. The central detector includes a silicon Micro Vertex Detector (MVD) and a Straw Tube Tracker (STT). Without any hardware trigger, large amounts of raw data are streaming into the data acquisition system. The data reduction task is performed in the online system by reconstruction algorithms programmed on FPGAs (Field Programmable Gate Arrays) as first level and on a farm of GPUs or PCs as a second level. One important part in the system is the online track reconstruction. In this presentation, an online tracking algorithm for helix tracking reconstruction in the solenoidal field is shown. The VHDL-based algorithm is tested with different types of events, at different event rate. Furthermore, a study of T0 extraction from the tracking algorithm is performed. A concept of simultaneous tracking and T0 determination is presented.

Sim Track User's Manual (v 1.0)

Energy Technology Data Exchange (ETDEWEB)

Luo, Y.

2010-01-27

SimTrack is a simple c++ library designed for the numeric particle tracking in the high energy accelerators. It adopts the 4th order symplectic integrator for the optical transport in the magnetic elements. The 4-D and 6-D weak-strong beam-beam treatments are integrated in it for the beam-beam studies. SimTrack is written with c++ class and standard template library. It provides versatile functions to manage elements and lines. It supports a large range of types of elements. New type of element can be easily created in the library. SimTrack calculates Twiss, coupling and fits tunes, chromaticities and corrects closed orbits. AC dipole and AC multipole are available in this library. SimTrack allows change of element parameters during tracking.

Suitability of markerless EPID tracking for tumor position verification in gated radiotherapy

International Nuclear Information System (INIS)

Serpa, Marco; Baier, Kurt; Guckenberger, Matthias; Cremers, Florian; Meyer, Juergen

2014-01-01

Purpose: To maximize the benefits of respiratory gated radiotherapy (RGRT) of lung tumors real-time verification of the tumor position is required. This work investigates the feasibility of markerless tracking of lung tumors during beam-on time in electronic portal imaging device (EPID) images of the MV therapeutic beam. Methods: EPID movies were acquired at ∼2 fps for seven lung cancer patients with tumor peak-to-peak motion ranges between 7.8 and 17.9 mm (mean: 13.7 mm) undergoing stereotactic body radiotherapy. The external breathing motion of the abdomen was synchronously measured. Both datasets were retrospectively analyzed inPortalTrack, an in-house developed tracking software. The authors define a three-step procedure to run the simulations: (1) gating window definition, (2) gated-beam delivery simulation, and (3) tumor tracking. First, an amplitude threshold level was set on the external signal, defining the onset of beam-on/-off signals. This information was then mapped onto a sequence of EPID images to generate stamps of beam-on/-hold periods throughout the EPID movies in PortalTrack, by obscuring the frames corresponding to beam-off times. Last, tumor motion in the superior-inferior direction was determined on portal images by the tracking algorithm during beam-on time. The residual motion inside the gating window as well as target coverage (TC) and the marginal target displacement (MTD) were used as measures to quantify tumor position variability. Results: Tumor position monitoring and estimation from beam's-eye-view images during RGRT was possible in 67% of the analyzed beams. For a reference gating window of 5 mm, deviations ranging from 2% to 86% (35% on average) were recorded between the reference and measured residual motion. TC (range: 62%–93%; mean: 77%) losses were correlated with false positives incidence rates resulting mostly from intra-/inter-beam baseline drifts, as well as sudden cycle-to-cycle fluctuations in exhale positions. Both

Circumpolar dynamics of a marine top-predator track ocean warming rates.

Science.gov (United States)

Descamps, Sébastien; Anker-Nilssen, Tycho; Barrett, Robert T; Irons, David B; Merkel, Flemming; Robertson, Gregory J; Yoccoz, Nigel G; Mallory, Mark L; Montevecchi, William A; Boertmann, David; Artukhin, Yuri; Christensen-Dalsgaard, Signe; Erikstad, Kjell-Einar; Gilchrist, H Grant; Labansen, Aili L; Lorentsen, Svein-Håkon; Mosbech, Anders; Olsen, Bergur; Petersen, Aevar; Rail, Jean-Francois; Renner, Heather M; Strøm, Hallvard; Systad, Geir H; Wilhelm, Sabina I; Zelenskaya, Larisa

2017-09-01

Global warming is a nonlinear process, and temperature may increase in a stepwise manner. Periods of abrupt warming can trigger persistent changes in the state of ecosystems, also called regime shifts. The responses of organisms to abrupt warming and associated regime shifts can be unlike responses to periods of slow or moderate change. Understanding of nonlinearity in the biological responses to climate warming is needed to assess the consequences of ongoing climate change. Here, we demonstrate that the population dynamics of a long-lived, wide-ranging marine predator are associated with changes in the rate of ocean warming. Data from 556 colonies of black-legged kittiwakes Rissa tridactyla distributed throughout its breeding range revealed that an abrupt warming of sea-surface temperature in the 1990s coincided with steep kittiwake population decline. Periods of moderate warming in sea temperatures did not seem to affect kittiwake dynamics. The rapid warming observed in the 1990s may have driven large-scale, circumpolar marine ecosystem shifts that strongly affected kittiwakes through bottom-up effects. Our study sheds light on the nonlinear response of a circumpolar seabird to large-scale changes in oceanographic conditions and indicates that marine top predators may be more sensitive to the rate of ocean warming rather than to warming itself. © 2017 John Wiley & Sons Ltd.

Determining of the track parameters in solid state nuclear track detectors Cr 39 due to alpha particles

International Nuclear Information System (INIS)

Kostic, D.; Nikezic, D.

1997-01-01

An equation of the etch pit wall is proposed to be used for simulation of the track growth and calculating the major and the minor axis of etch pit opening. Dependence on the following parameters is set up: distance along a track from the point where the particle entered the detector, ratio of the track etch wall to the bulk etch rate, integration constant determined from particle penetration depth and normal distance from the particle trajectory to the etch pit wall. The corresponding computer program was written. The input parameters of this program are: alpha particles energy, incidence angle and removed layer; the output gives track parameters. The results obtained by this method are compared to another approach given by Somogy and Szalay (1973) and a reasonably good agreement is found. (author)

Application of fission track analysis to hydrocarbon exploration

International Nuclear Information System (INIS)

Duddy, I.R.; Green, P.F.; Gleadow, A.J.W.; Marshallsea, S.; Tingate, P.; Laslett, G.M.; Hegarty, K.A.; Lovering, J.F.

1985-01-01

The temperature range over which fission tracks in apatite show observable annealing effects coincides with that responsible for the maximum generation of liquid hydrocarbons. Work is currently in progress in a number of Australian and overseas sedimentary basins, applying Apatite Fission Track Analysis (AFTA) to investigate the thermal evolution of these hydrocarbon prospective regions

Computer-aided target tracking in motion analysis studies

Science.gov (United States)

Burdick, Dominic C.; Marcuse, M. L.; Mislan, J. D.

1990-08-01

Motion analysis studies require the precise tracking of reference objects in sequential scenes. In a typical situation, events of interest are captured at high frame rates using special cameras, and selected objects or targets are tracked on a frame by frame basis to provide necessary data for motion reconstruction. Tracking is usually done using manual methods which are slow and prone to error. A computer based image analysis system has been developed that performs tracking automatically. The objective of this work was to eliminate the bottleneck due to manual methods in high volume tracking applications such as the analysis of crash test films for the automotive industry. The system has proven to be successful in tracking standard fiducial targets and other objects in crash test scenes. Over 95 percent of target positions which could be located using manual methods can be tracked by the system, with a significant improvement in throughput over manual methods. Future work will focus on the tracking of clusters of targets and on tracking deformable objects such as airbags.

Dynamic kirigami structures for integrated solar tracking

Science.gov (United States)

Lamoureux, Aaron; Lee, Kyusang; Shlian, Matthew; Forrest, Stephen R.; Shtein, Max

2015-01-01

Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. Here we use kirigami (the art of paper cutting) to realize novel solar cells where tracking is integral to the structure at the substrate level. Specifically, an elegant cut pattern is made in thin-film gallium arsenide solar cells, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°. We analyze the combined optical and mechanical properties of the tracking system, and demonstrate a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices. PMID:26348820

Single-Photon Tracking for High-Speed Vision

Directory of Open Access Journals (Sweden)

Istvan Gyongy

2018-01-01

Full Text Available Quanta Imager Sensors provide photon detections at high frame rates, with negligible read-out noise, making them ideal for high-speed optical tracking. At the basic level of bit-planes or binary maps of photon detections, objects may present limited detail. However, through motion estimation and spatial reassignment of photon detections, the objects can be reconstructed with minimal motion artefacts. We here present the first demonstration of high-speed two-dimensional (2D tracking and reconstruction of rigid, planar objects with a Quanta Image Sensor, including a demonstration of depth-resolved tracking.

Report of the Central Tracking Group

International Nuclear Information System (INIS)

Cassel, D.G.; Hanson, G.G.

1986-10-01

Issues involved in building a realistic central tracking system for a general-purpose 4π detector for the SSC are addressed. Such a central tracking system must be capable of running at the full design luminosity of 10 33 cm -2 s -1 . Momentum measurement was required in a general-purpose 4π detector. Limitations on charged particle tracking detectors at the SSC imposed by rates and radiation damage are reviewed. Cell occupancy is the dominant constraint, which led us to the conclusion that only small cells, either wires or straw tubes, are suitable for a central tracking system at the SSC. Mechanical problems involved in building a central tracking system of either wires or straw tubes were studied, and our conclusion was that it is possible to build such a large central tracking system. Of course, a great deal of research and development is required. We also considered central tracking systems made of scintillating fibers or silicon microstrips, but our conclusion was that neither is a realistic candidate given the current state of technology. We began to work on computer simulation of a realistic central tracking system. Events from interesting physics processes at the SSC will be complex and will be further complicated by hits from out-of-time bunch crossings and multiple interactions within the same bunch crossing. Detailed computer simulations are needed to demonstrate that the pattern recognition and tracking problems can be solved

FPGA Online Tracking Algorithm for the PANDA Straw Tube Tracker

Science.gov (United States)

Liang, Yutie; Ye, Hua; Galuska, Martin J.; Gessler, Thomas; Kuhn, Wolfgang; Lange, Jens Soren; Wagner, Milan N.; Liu, Zhen'an; Zhao, Jingzhou

2017-06-01

A novel FPGA based online tracking algorithm for helix track reconstruction in a solenoidal field, developed for the PANDA spectrometer, is described. Employing the Straw Tube Tracker detector with 4636 straw tubes, the algorithm includes a complex track finder, and a track fitter. Implemented in VHDL, the algorithm is tested on a Xilinx Virtex-4 FX60 FPGA chip with different types of events, at different event rates. A processing time of 7 $\\mu$s per event for an average of 6 charged tracks is obtained. The momentum resolution is about 3\\% (4\\%) for $p_t$ ($p_z$) at 1 GeV/c. Comparing to the algorithm running on a CPU chip (single core Intel Xeon E5520 at 2.26 GHz), an improvement of 3 orders of magnitude in processing time is obtained. The algorithm can handle severe overlapping of events which are typical for interaction rates above 10 MHz.

Global track finder for Belle II experiment

Energy Technology Data Exchange (ETDEWEB)

Trusov, Viktor; Feindt, Michael; Heck, Martin; Kuhr, Thomas; Goldenzweig, Pablo [Karlsruhe Institute of Technology, IEKP (Germany); Collaboration: Belle II-Collaboration

2015-07-01

We present an implementation of a method based on the Legendre transformation for reconstruction charged particle tracks in the central drift chamber of the Belle II experiment. The method is designed for fast track finding and restoring circular patterns of track hits in transverse plane. It is done by searching for common tangents to drift circles of hits in the conformal space. With known transverse trajectories longitudinal momentum estimation performed by assigning stereo hits followed by determination of the track parameters. The method includes algorithms responsible for track quality estimation and reduction of rate of fakes. The work is targeting at increasing the efficiency and reducing the execution time because the computing power available to the experiment is limited. The algorithm is developed within the Belle II software environment with using Monte-Carlo simulation for probing its efficiency.

Effects of track structure and cell inactivation on the calculation of heavy ion mutation rates in mammalian cells

Science.gov (United States)

Cucinotta, F. A.; Wilson, J. W.; Shavers, M. R.; Katz, R.

1996-01-01

It has long been suggested that inactivation severely effects the probability of mutation by heavy ions in mammalian cells. Heavy ions have observed cross sections of inactivation that approach and sometimes exceed the geometric size of the cell nucleus in mammalian cells. In the track structure model of Katz the inactivation cross section is found by summing an inactivation probability over all impact parameters from the ion to the sensitive sites within the cell nucleus. The inactivation probability is evaluated using the dose-response of the system to gamma-rays and the radial dose of the ions and may be equal to unity at small impact parameters for some ions. We show how the effects of inactivation may be taken into account in the evaluation of the mutation cross sections from heavy ions in the track structure model through correlation of sites for gene mutation and cell inactivation. The model is fit to available data for HPRT mutations in Chinese hamster cells and good agreement is found. The resulting calculations qualitatively show that mutation cross sections for heavy ions display minima at velocities where inactivation cross sections display maxima. Also, calculations show the high probability of mutation by relativistic heavy ions due to the radial extension of ions track from delta-rays in agreement with the microlesion concept. The effects of inactivation on mutations rates make it very unlikely that a single parameter such as LET or Z*2/beta(2) can be used to specify radiation quality for heavy ion bombardment.

Simultaneous Tracking of Multiple Points Using a Wiimote

Science.gov (United States)

Skeffington, Alex; Scully, Kyle

2012-01-01

This paper reviews the construction of an inexpensive motion tracking and data logging system, which can be used for a wide variety of teaching experiments ranging from entry-level physics courses to advanced courses. The system utilizes an affordable infrared camera found in a Nintendo Wiimote to track IR LEDs mounted to the objects to be…

Predicting Agency Rating Migrations with Spread Implied Ratings

OpenAIRE

Jianming Kou; Dr Simone Varotto

2005-01-01

Investors traditionally rely on credit ratings to price debt instruments. However, rating agencies are known to be prudent in their approach to rating revisions, which results in delayed ratings adjustments to mutating credit conditions. For a large set of eurobonds we derive credit spread implied ratings and compare them with the ratings issued by rating agencies. Our results indicate that spread implied ratings often anticipate future movement of agency ratings and hence could help track cr...

Low-voltage electroosmotic pumping using polyethylene terephthalate track-etched membrane

Energy Technology Data Exchange (ETDEWEB)

Wang Ceming; Wang Lin [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xue Jianming, E-mail: jmxue@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Center for Applied Physics and Technology, Peking University, Beijing 100871 (China)

2012-09-01

We present experimental investigations of electroosmotic (EO) pumping using polyethylene terephthalate (PET) track-etched membrane at a low applied voltage. An EO pump based on PET track-etched membrane has been designed and fabricated. Pumping performance of the device is experimentally studied in terms of flow rate as a function of applied voltage and KCl aqueous concentration. The PET track-etched membrane EO pump can generate flow rates on the order of 10 {mu}l min{sup -1} cm{sup -2} at several applied volts. The measured flow rate tends to decrease with increasing KCl aqueous concentration. In addition, we study the EO flow in cylindrical nanopore with use of a continuum model, composed of Nernst Planck equations, Poisson equation and Navier Stokes equations.

Adaptive Correlation Model for Visual Tracking Using Keypoints Matching and Deep Convolutional Feature

Directory of Open Access Journals (Sweden)

Yuankun Li

2018-02-01

Full Text Available Although correlation filter (CF-based visual tracking algorithms have achieved appealing results, there are still some problems to be solved. When the target object goes through long-term occlusions or scale variation, the correlation model used in existing CF-based algorithms will inevitably learn some non-target information or partial-target information. In order to avoid model contamination and enhance the adaptability of model updating, we introduce the keypoints matching strategy and adjust the model learning rate dynamically according to the matching score. Moreover, the proposed approach extracts convolutional features from a deep convolutional neural network (DCNN to accurately estimate the position and scale of the target. Experimental results demonstrate that the proposed tracker has achieved satisfactory performance in a wide range of challenging tracking scenarios.

Interactive navigation and bronchial tube tracking in virtual bronchoscopy.

Science.gov (United States)

Heng, P A; Fung, P F; Wong, T T; Siu, Y H; Sun, H

1999-01-01

An interactive virtual environment for simulation of bronchoscopy is developed. Medical doctor can safely plan their surgical bronchoscopy using the virtual environment without any invasive diagnosis which may risk the patient's health. The 3D pen input device of the system allows the doctor to navigate and visualize the bronchial tree of the patient naturally and interactively. To navigate the patient's bronchial tree, a vessel tracking process is required. While manual tracking is tedious and labor-intensive, fully automatic tracking may not be reliable. We propose a semi-automatic tracking technique called Intelligent Path Tracker which provides automation and enough user control during the vessel tracking. To support an interactive frame rate, we also introduce a new volume rendering acceleration technique, named as IsoRegion Leaping. The volume rendering is further accelerated by distributed rendering on a TCP/IP-based network of low-cost PCs. With these approaches, a 256 x 256 x 256 volume data of human lung, can be navigated and visualized at a frame rate of over 10 Hz in our virtual bronchoscopy system.

Spatial Cognition and Range Use in Free-Range Laying Hens.

Science.gov (United States)

Campbell, Dana L M; Talk, Andrew C; Loh, Ziyang A; Dyall, Tim R; Lee, Caroline

2018-02-08

Radio-frequency identification tracking shows individual free-range laying hens vary in range use, with some never going outdoors. The range is typically more environmentally complex, requiring navigation to return to the indoor resources. Outdoor-preferring hens may have improved spatial abilities compared to indoor-preferring hens. Experiment 1 tested 32 adult ISA Brown hens in a T-maze learning task that showed exclusively-indoor birds were slowest to reach the learning success criterion ( p 0.05), the age that coincided with the onset of lay. Enriched birds that were faster to learn the maze task showed more range visits in the first 4 weeks of range access. Enriched and non-enriched birds showed no differences in telencephalon or hippocampal volume ( p > 0.05). Fear may reduce spatial abilities but further testing with more pen replicates per early rearing treatments would improve our understanding of the relationship between spatial cognitive abilities and range use.

A modified fast-track program for pancreatic surgery: a prospective single-center experience.

Science.gov (United States)

di Sebastiano, Pierluigi; Festa, Leonardina; De Bonis, Antonio; Ciuffreda, Andrea; Valvano, Maria Rosa; Andriulli, Angelo; di Mola, F Francesco

2011-03-01

The objective of this study is to evaluate the impact of a fast-track protocol in a high-volume center for patients with pancreatic disorders. The concept of fast-track surgery allowing accelerated postoperative recovery is accepted in colorectal surgery, but efficacy data are only preliminary for patients undergoing major pancreatic surgery. We aimed to evaluate the impact of a modified fast-track protocol in a high-volume center for patients with pancreatic disorders. Between February 2005 and January 2010, 145 subjects had resective pancreatic surgery and were enrolled in the program. Essential features of the program were no preanaesthetic medication, upper and lower air-warming device, avoidance of excessive i.v. fluids perioperatively, effective control of pain, early reinstitution of oral feeding, and immediate mobilization and restoration of bowel function following surgery. Outcome measures were postoperative complications such as pancreatic fistula, delayed gastric emptying, biliary leak, intra-abdominal abscess, post-pancreatectomy hemorrhage, acute pancreatitis, wound infection, 30-day mortality, postoperative hospital stay, and readmission rates. On average, patients were discharged on postoperative day 10 (range 6-69), with a 30-day readmission rate of 6.2%. Percentage of patients with at least one complication was 38.6%. Pancreatic anastomotic leakage occurred in seven of 101 pancreatico-jejunostomies, and biliary leak in three of 109 biliary jejunostomies. Postoperative hemorrhage occurred in ten (6.9%) patients and wound infection in nine (6.2%) cases. In-hospital mortality was 2.7%. Fast-track parameters, such as normal food and first stool, correlated significantly with early discharge (jaundice, and resumption of normal diet by the 5th postoperative day were independent factors of early discharge. Fast-track programs are feasible, easy, and also applicable for patients undergoing a major surgery such as pancreatic resection.

Online track processor for the CDF upgrade

International Nuclear Information System (INIS)

Thomson, E. J.

2002-01-01

A trigger track processor, called the eXtremely Fast Tracker (XFT), has been designed for the CDF upgrade. This processor identifies high transverse momentum (> 1.5 GeV/c) charged particles in the new central outer tracking chamber for CDF II. The XFT design is highly parallel to handle the input rate of 183 Gbits/s and output rate of 44 Gbits/s. The processor is pipelined and reports the result for a new event every 132 ns. The processor uses three stages: hit classification, segment finding, and segment linking. The pattern recognition algorithms for the three stages are implemented in programmable logic devices (PLDs) which allow in-situ modification of the algorithm at any time. The PLDs reside on three different types of modules. The complete system has been installed and commissioned at CDF II. An overview of the track processor and performance in CDF Run II are presented

Ultra-Wideband Tracking System Design for Relative Navigation

Science.gov (United States)

Ni, Jianjun David; Arndt, Dickey; Bgo, Phong; Dekome, Kent; Dusl, John

2011-01-01

This presentation briefly discusses a design effort for a prototype ultra-wideband (UWB) time-difference-of-arrival (TDOA) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being designed for use in localization and navigation of a rover in a GPS deprived environment for surface missions. In one application enabled by the UWB tracking, a robotic vehicle carrying equipments can autonomously follow a crewed rover from work site to work site such that resources can be carried from one landing mission to the next thereby saving up-mass. The UWB Systems Group at JSC has developed a UWB TDOA High Resolution Proximity Tracking System which can achieve sub-inch tracking accuracy of a target within the radius of the tracking baseline [1]. By extending the tracking capability beyond the radius of the tracking baseline, a tracking system is being designed to enable relative navigation between two vehicles for surface missions. A prototype UWB TDOA tracking system has been designed, implemented, tested, and proven feasible for relative navigation of robotic vehicles. Future work includes testing the system with the application code to increase the tracking update rate and evaluating the linear tracking baseline to improve the flexibility of antenna mounting on the following vehicle.

Three-Dimensional Planetary Surface Tracking Based on a Simple Ultra-Wideband Impulse-Radio Infrastructure

Science.gov (United States)

Barton, Richard J.; Ni, David; Ngo, Phong

2010-01-01

Several prototype ultra-wideband (UWB) impulse-radio (IR) tracking systems are currently under development at NASA Johnson Space Center (JSC). These systems are being studied for use in tracking of Lunar/Mars rovers and astronauts during early exploration missions when satellite navigation systems (such as GPS) are not available. To date, the systems that have been designed and tested are intended only for two-dimensional location and tracking, but these designs can all be extended to three-dimensional tracking with only minor modifications and increases in complexity. In this presentation, we will briefly review the design and performance of two of the current 2-D systems: one designed specifically for short-range, extremely high-precision tracking (approximately 1-2 cm resolution) and the other designed specifically for much longer range tracking with less stringent precision requirements (1-2 m resolution). We will then discuss a new multi-purpose system design based on a simple UWB-IR architecture that can be deployed easily on a planetary surface to support arbitrary three-dimensional localization and tracking applications. We will discuss utilization of this system as an infrastructure to provide both short-range and long-range tracking and analyze the localization performance of the system in several different configurations. We will give theoretical performance bounds for some canonical system configurations and compare these performance bounds with both numerical simulations of the system as well as actual experimental system performance evaluations.

Control system design for UAV trajectory tracking

Science.gov (United States)

Wang, Haitao; Gao, Jinyuan

2006-11-01

In recent years, because of the emerging requirements for increasing autonomy, the controller of uninhabited air vehicles must be augmented with a very sophisticated autopilot design which is capable of tracking complex and agile maneuvering trajectory. This paper provides a simplified control system framework to solve UAV maneuvering trajectory tracking problem. The flight control system is divided into three subsystems including command generation, transformation and allocation. According to the kinematics equations of the aircraft, flight path angle commands can be generated by desired 3D position from path planning. These commands are transformed to body angular rates through direct nonlinear mapping, which is simpler than common multi-loop method based on time scale separation assumption. Then, by using weighted pseudo-inverse method, the control surface deflections are allocated to follow body angular rates from the previous step. In order to improve the robustness, a nonlinear disturbance observer-based approach is used to compensate the uncertainty of system. A 6DOF nonlinear UAV model is controlled to demonstrate the performance of the trajectory tracking control system. Simulation results show that the control strategy is easy to be realized and the precision of tracking is satisfying.

Fast-track aquifer characterization and bioremediation of groundwater

International Nuclear Information System (INIS)

Owen, S.B.; Erskine, J.A.; Adkisson, C.

1995-01-01

A short duration step-drawdown pumping test has been used to characterize a highly permeable aquifer contaminated with petroleum hydrocarbons in support of an in situ, closed loop extraction and reinjection bioremediation system for groundwater. The short-term pumping test produces a manageable quantity of contaminated groundwater while yielding a range of values for transmissivity and specific yield parameters. This range of aquifer coefficients is used in an analytical model to estimate a range of groundwater extraction rates that provide a suitable radius of influence for the extraction and reinjection system. A multi-enzyme complex catalyzed bioremediation process has been used to aerobically degrade petroleum hydrocarbons. Enzymes, amino acids, and biosurfactants are supplied to the extracted groundwater to significantly speed up the degradation by naturally occurring bacteria. During the process, amino acids promote the rapid growth of the microbial population while enzymes and bacteria attach to hydrocarbons forming a transformation state complex that degrades to fatty acids, carbon dioxide, and water. This paper presents a case study of a fast-track bioremediation using pumping test data, analytical modeling, and an enzyme technology

Latent tracks in polymeric etched track detectors

International Nuclear Information System (INIS)

Yamauchi, Tomoya

2013-01-01

Track registration properties in polymeric track detectors, including Poly(allyl diglycol carbonate), Bispenol A polycarbonate, Poly(ethylen terephtarate), and Polyimide, have been investigated by means of Fourie transform Infararede FT-IR spectrometry. Chemical criterion on the track formation threshold has been proposes, in stead of the conventional physical track registration models. (author)

Quality of Slab Track Construction - Track Alignment Design and Track Geometry

Science.gov (United States)

Šestáková, Janka

2015-05-01

The slab track superstructure design (without ballast) is a perspective construction especially for building tunnels and bridges in the modernized sections of railway tracks in Slovakia. Monitoring of the structure described in this article is focused on the transition areas between standard structure with ballast and slab track construction.

Tracking Outfield Employees using GPS in Web Applications

Directory of Open Access Journals (Sweden)

Kasinathan Vinothini

2018-01-01

Full Text Available This paper presents e-Track, a web-based tracking system for outfield employees in order to cater for various business activities as demanded by the business owners. Such demands may range from a simple task assignment, to employee location tracking and remote observation of the employees’ task progress. The objective of the proposed system is two-fold. First, the employees to access the application and clocks-in work. Second, a standalone web system for the employers to determine the approximate location of the staff assigned with outfield duties. The IP address recognition will ensure no buddy punching takes place. e-Track is hoped to increase efficiency among employees by saving time travelling between branches during outfield duties. In the future, e-Track will be integrated with claim and payment modules to support arrangement for outfield duties.

Tracking the attenuation and nonbreaking dissipation of swells using altimeters

Science.gov (United States)

Jiang, Haoyu; Stopa, Justin E.; Wang, He; Husson, Romain; Mouche, Alexis; Chapron, Bertrand; Chen, Ge

2016-02-01

A method for systematically tracking swells across oceanic basins is developed by taking advantage of high-quality data from space-borne altimeters and wave model output. The evolution of swells is observed over large distances based on 202 swell events with periods ranging from 12 to 18 s. An empirical attenuation rate of swell energy of about 4 × 10-7 m-1 is estimated using these observations, and the nonbreaking energy dissipation rates of swells far away from their generating areas are also estimated using a point source model. The resulting acceptance range of nonbreaking dissipation rates is -2.5 to 5.0 × 10-7 m-1, which corresponds to a dissipation e-folding scales of at least 2000 km for steep swells, to almost infinite for small-amplitude swells. These resulting rates are consistent with previous studies using in-situ and synthetic aperture radar (SAR) observations. The frequency dispersion and angular spreading effects during swell propagation are discussed by comparing the results with other studies, demonstrating that they are the two dominant processes for swell height attenuation, especially in the near field. The resulting dissipation rates from these observations can be used as a reference for ocean engineering and wave modeling, and for related studies such as air-sea and wind-wave-turbulence interactions.

Launch vehicle tracking enhancement through Global Positioning System Metric Tracking

Science.gov (United States)

Moore, T. C.; Li, Hanchu; Gray, T.; Doran, A.

United Launch Alliance (ULA) initiated operational flights of both the Atlas V and Delta IV launch vehicle families in 2002. The Atlas V and Delta IV launch vehicles were developed jointly with the US Air Force (USAF) as part of the Evolved Expendable Launch Vehicle (EELV) program. Both Launch Vehicle (LV) families have provided 100% mission success since their respective inaugural launches and demonstrated launch capability from both Vandenberg Air Force Base (VAFB) on the Western Test Range and Cape Canaveral Air Force Station (CCAFS) on the Eastern Test Range. However, the current EELV fleet communications, tracking, & control architecture & technology, which date back to the origins of the space launch business, require support by a large and high cost ground footprint. The USAF has embarked on an initiative known as Future Flight Safety System (FFSS) that will significantly reduce Test Range Operations and Maintenance (O& M) cost by closing facilities and decommissioning ground assets. In support of the FFSS, a Global Positioning System Metric Tracking (GPS MT) System based on the Global Positioning System (GPS) satellite constellation has been developed for EELV which will allow both Ranges to divest some of their radar assets. The Air Force, ULA and Space Vector have flown the first 2 Atlas Certification vehicles demonstrating the successful operation of the GPS MT System. The first Atlas V certification flight was completed in February 2012 from CCAFS, the second Atlas V certification flight from VAFB was completed in September 2012 and the third certification flight on a Delta IV was completed October 2012 from CCAFS. The GPS MT System will provide precise LV position, velocity and timing information that can replace ground radar tracking resource functionality. The GPS MT system will provide an independent position/velocity S-Band telemetry downlink to support the current man-in-the-loop ground-based commanded destruct of an anomalous flight- The system

Biosonar adjustments to target range of echolocating bottlenose dolphins (Tursiops sp.) in the wild

DEFF Research Database (Denmark)

Jensen, Frants Havmand; Bejder, Lars; Wahlberg, Magnus

2009-01-01

Toothed whales use echolocation to locate and track prey. Most knowledge of toothed whale echolocation stems from studies on trained animals, and little is known about how toothed whales regulate and use their biosonar systems in the wild. Recent research suggests that an automatic gain control...... array echo. However, for interclick intervals longer than 30–40 ms, source levels were not limited by the repetition rate. Thus, pneumatic constraints in the sound-production apparatus cannot account for source level adjustments to range as a possible automatic gain control mechanism for target ranges...

Central and forward tracking collaboration

International Nuclear Information System (INIS)

Foster, R.; Hanson, G.; Luehring, F.; Luo, X.; Martin, B.; Ogren, H.; Rust, D.R.; Wente, E.; Adrian, B.; Alexander, D.; Ells, F.; Erdos, E.; Ford, W.T.; Johnson, D.; Lohner, M.; Rankin, P.; Schultz, G.; Newcomer, F.M.; Van Berg, R.; Williams, H.H.; Arai, Y.; Hess, D.; Kadyk, J.A.; Palounek, A.P.T.; Wise, J.; Chapman, J.W.; Dunn, A.; Edwards, M.; Hiddleston, J.W.; Payne, B.T.; Amery, C.A.; Bailey, J.M.; Dainton, J.B.; Gabathuler, E.; Maxfield, S.J.; Morton, J.M.; Muir, A.; Patel, G.D.; Sanders, P.; Raine, C.; Saxon, D.H.; Hackworth, D.T.; Swensrud, R.L.; Newfield, S.; Sadler, C.; Va'vra, J.

1991-01-01

The goal of this subsystem R ampersand D project is to carry out a detailed study and design of a complete wire chamber tracking system covering pseudorapidity |η| ≤ 2.5 in a solenoidal detector for the SSC. Most of our group are now part of the Solenoidal Detector Collaboration (SDC), so the work has evolved into developing a tracking system conceptual design for the SDC detector. The design discussed in this report uses straw tube drift chambers for the central tracking region. Because of the high rates in the SSC environment, a small cell design is needed for wire chambers in the central region. Straw tubes as small cells offer many advantages because the sense wire is enclosed in a continuous cathode, and the wire tension due to the sense wire only can be supported without a massive structure. The straw tubes are grouped together to form superlayers in order to provide local track segments. The superlayers are composed of modules consisting of about two hundred straw tubes enclosed in a carbon fiber composite shell. Straw tubes have been used in previous experiments for small vertex drift chambers. However, they have never before been used for a large tracking system

PUC fast track nips returns

International Nuclear Information System (INIS)

Anon.

1990-01-01

In the first of what it says will be annual cost-of-capital proceedings to set returns on equity and rates of return on rate base for electric utilities, the California Public Utilities Commission (PUC) lowered from 1989 levels the 1990 returns on common equity (ROE) and rates of return (ROR) for the state's four major investor-owned electric utilities. Under this fast-track procedure, by May 8 of every year, utilities will have to file an application for rate adjustments that reflect their projected costs of capital for the following year

Online tracking applications of the general purpose EDRO Board

CERN Document Server

Annovi, A; The ATLAS collaboration; Cervini, F; Crescioli, F; Fabbri, L; Franchini, M; Giannetti, P; Giannuzzi, F; Giorgi, F; Magalotti, D; Piendibene, M; Sbarra, C; Valentinetti, S; Mauro, V; Zoccoli, A

2012-01-01

The capability to perform extremely fast track reconstruction online is becoming more and more important for the LHC upgrade as well as the next generation of HEP experiments, where the expected instantaneous luminosities (in excess of 10^34 /cm2/s) and the very low signal/background ratio ask for fast and clean identification of the main characteristics of interesting events. The Slim5 R&D project studied different aspects of fast and high-precision tracking in dedicated hardware: data-push silicon sensors, high bandwidth DAQ systems and Associative Memories (AM) for fast track identification. The central element of the development system is a high traffic board, called EDRO, capable of collecting and processing digital data with an input rate of 16 Gbps. The input hits, suitably formatted or clusterized, are sent to an AM board sending back candidate tracks, which are identified at a rate of 40 MHz. The EDRO board is then able to deliver triggers and formatted events for further processing. The EDRO-AM ...

Annealing effects in solid-state track recorders

International Nuclear Information System (INIS)

Gold, R.; Roberts, J.H.; Ruddy, F.H.

1981-01-01

Current analyses of the annealing process in Solid State Track Recorders (SSTR) reveal fundamental misconceptions. The use of the Arrhenius equation to describe the decrease in track density resulting from annealing is shown to be incorrect. To overcome these deficiencies, generalized reaction rate theory is used to describe the annealing process in SSTR. Results of annealing experiments are used to guide this theoretical formulation. Within this framework, the concept of energy per etchable defect for SSTR is introduced. A general correlation between sensitivity and annealing susceptibility in SSTR is deduced. In terms of this general theory, the apparent correlation between fission track size and fission track density observed under annealing is readily explained. Based on this theoretical treatment of annealing phenomena, qualitative explanations are advanced for current enigmas in SSTR cosmic ray work

An “artificial retina” processor for track reconstruction at the full LHC crossing rate

International Nuclear Information System (INIS)

Abba, A.; Bedeschi, F.; Caponio, F.; Cenci, R.; Citterio, M.; Cusimano, A.; Fu, J.; Geraci, A.; Grizzuti, M.; Lusardi, N.; Marino, P.; Morello, M.J.; Neri, N.; Ninci, D.; Petruzzo, M.; Piucci, A.; Punzi, G.; Ristori, L.; Spinella, F.

2016-01-01

We present the latest results of an R&D study for a specialized processor capable of reconstructing, in a silicon pixel detector, high-quality tracks from high-energy collision events at 40 MHz. The processor applies a highly parallel pattern-recognition algorithm inspired to quick detection of edges in mammals visual cortex. After a detailed study of a real-detector application, demonstrating that online reconstruction of offline-quality tracks is feasible at 40 MHz with sub-microsecond latency, we are implementing a prototype using common high-bandwidth FPGA devices.

An “artificial retina” processor for track reconstruction at the full LHC crossing rate

Energy Technology Data Exchange (ETDEWEB)

Abba, A. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Politecnico di Milano, Milano (Italy); Bedeschi, F. [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); Caponio, F. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Politecnico di Milano, Milano (Italy); Cenci, R., E-mail: riccardo.cenci@pi.infn.it [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); Scuola Normale Superiore, Pisa (Italy); Citterio, M. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Cusimano, A. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Politecnico di Milano, Milano (Italy); Fu, J. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Geraci, A.; Grizzuti, M.; Lusardi, N. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Politecnico di Milano, Milano (Italy); Marino, P.; Morello, M.J. [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); Scuola Normale Superiore, Pisa (Italy); Neri, N. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Ninci, D. [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); Università di Pisa, Pisa (Italy); Petruzzo, M. [Istituto Nazionale di Fisica Nucleare – Sez. di Milano, Milano (Italy); Università di Milano, Milano (Italy); Piucci, A.; Punzi, G. [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); Università di Pisa, Pisa (Italy); Ristori, L. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Spinella, F. [Istituto Nazionale di Fisica Nucleare – Sez. di Pisa, Pisa (Italy); and others

2016-07-11

We present the latest results of an R&D study for a specialized processor capable of reconstructing, in a silicon pixel detector, high-quality tracks from high-energy collision events at 40 MHz. The processor applies a highly parallel pattern-recognition algorithm inspired to quick detection of edges in mammals visual cortex. After a detailed study of a real-detector application, demonstrating that online reconstruction of offline-quality tracks is feasible at 40 MHz with sub-microsecond latency, we are implementing a prototype using common high-bandwidth FPGA devices.

Searching for long-range dependence in real effective exchange rate: towards parity?

Directory of Open Access Journals (Sweden)

André M. Marques

2015-12-01

Full Text Available Abstract After the widespread adoption of flexible exchange rate regime since 1973 the volatility of the exchange rate has increased, as a consequence of greater trade openness and financial integration. As a result, it has become difficult to find evidence of the purchasing power parity hypothesis (PPP. This study investigates the possibility of a fall in the persistence of the real exchange rate as a consequence of the financial and commercial integration by employing monthly real effective exchange rate dataset provided by the International Monetary Fund (IMF. Beginning with an exploratory data analysis in the frequency domain, the fractional coefficient d was estimated employing the bias-reduced estimator on a sample of 20 countries over the period ranging from 1975 to 2011. As the main novelty, this study applies a bias-reduced log-periodogram regression estimator instead of the traditional method proposed by GPH which eliminates the first and higher orders biases by a data-dependent plug-in method for selecting the number of frequencies to minimize asymptotic mean-squared error (MSE. Additionally, this study also estimates a moving window of fifteen years to observe the path of the fractional coefficient in each country. No evidence was found of a statistically significant change in the persistence of the real exchange rate.

Tracking with wire chambers at high luminosities

International Nuclear Information System (INIS)

Hanson, G.G.

1989-12-01

Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs

Random set particle filter for bearings-only multitarget tracking

Science.gov (United States)

Vihola, Matti

2005-05-01

The random set approach to multitarget tracking is a theoretically sound framework that covers joint estimation of the number of targets and the state of the targets. This paper describes a particle filter implementation of the random set multitarget filter. The contribution of this paper to the random set tracking framework is the formulation of a measurement model where each sensor report is assumed to contain at most one measurement. The implemented filter was tested in synthetic bearings-only tracking scenarios containing up to two targets in the presence of false alarms and missed measurements. The estimated target state consisted of 2D position and velocity components. The filter was capable to track the targets fairly well despite of the missing measurements and the relatively high false alarm rates. In addition, the filter showed robustness against wrong parameter values of false alarm rates. The results that were obtained during the limited tests of the filter show that the random set framework has potential for challenging tracking situations. On the other hand, the computational burden of the described implementation is quite high and increases approximately linearly with respect to the expected number of targets.

Indigenous approach to nuclear track studies in academics

Energy Technology Data Exchange (ETDEWEB)

Tsuruta, T., E-mail: tsuruta@msa.kindai.ac.j [Atomic Energy Research Institute, Kinki University, Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Interdisciplinary Graduate School of Science and Engineering, Kinki University, Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Hohara, S. [Atomic Energy Research Institute, Kinki University, Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Nakanishi, Y. [Interdisciplinary Graduate School of Science and Engineering, Kinki University, Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Shimba, H. [Faculty of Science and Engineering, Kinki University, Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan)

2009-10-15

In a study aimed at introduction of the nuclear tracks in solids into high school education, several experimental methods were developed and proposed. From the experiments of the basic course, students will be able to learn various characteristics of alpha-particles such as straight-line motion, short range in material, formation of the track, etc. From the experiments of the advanced course, the students will be able to learn various characteristics of neutrons such as (n,alpha) reaction, recoil reaction, neutron fluence, the relationship between neutron energy and cross section, etc. It is an advantage of the solid state track detector that the trails of invisible radiation can be observed as clearly visible tracks. The tracks must arouse student's interest in radiation. It is expected that more complete education of radiation in school cultivate people's better understanding of this field.

The Danish Head and Neck Cancer fast-track program

DEFF Research Database (Denmark)

Roennegaard, Anders B.; Rosenberg, Tine; Bjørndal, Kristine

2018-01-01

-track clinical pathway solutions. Objectives: The objectives of this study were 1) to present the setup of the head and neck cancer (HNC) fast-track program at Odense University Hospital (OUH) as an example of the Danish model and 2) to present patient characteristics, diagnostic outcome, cancer detection rate...

Extending the Dynamic Range of a Time Projection Chamber

Science.gov (United States)

Estee, Justin; S πRIT Collaboration

2017-09-01

The use of Time Projection Chambers (TPCs) in intermediate heavy ion reactions faces some challenges in addressing the energy losses that range from the small energy loss of relativistic pions to the large energy loss of slow moving heavy ions. A typical trade-off can be to set the smallest desired signals to be well within the lower limits of the dynamic range of the electronics while allowing for some larger signals to saturate the electronics. With wire plane anodes, signals from readout pads further away from the track remain unsaturated and allow signals from tracks with saturated pads to be accurately recovered. We illustrate this technique using data from the SAMURAI Pion-Reconstruction and Ion-Tracker (S πRIT) TPC , which recently measured pions and light charged particles in collisions of Sn+Sn isotopes. Our method exploits knowledge of how the induced charge distribution depends on the distance from the track to smoothly extend dynamic range even when some of the pads in the track are saturated. To accommodate the analysis of slow moving heavy ions, we have extended the Bichsel energy loss distributions to handle slower moving ions as well. In this talk, I will discuss a combined approach which successfully extends the dynamic range of the TPC electronics. This work is supported by the U.S. DOE under Grant Nos. DE-SC0014530, DE-NA0002923, US NSF Grant No. PHY-1565546 and the Japan MEXT KAKENHI Grant No. 24105004.

Markerless 3D Face Tracking

DEFF Research Database (Denmark)

Walder, Christian; Breidt, Martin; Bulthoff, Heinrich

2009-01-01

We present a novel algorithm for the markerless tracking of deforming surfaces such as faces. We acquire a sequence of 3D scans along with color images at 40Hz. The data is then represented by implicit surface and color functions, using a novel partition-of-unity type method of efficiently...... the scanned surface, using the variation of both shape and color as features in a dynamic energy minimization problem. Our prototype system yields high-quality animated 3D models in correspondence, at a rate of approximately twenty seconds per timestep. Tracking results for faces and other objects...

Building a tracking detector for the P2 experiment

Energy Technology Data Exchange (ETDEWEB)

Zimmermann, Marco [Institute of Nuclear Physics, Johannes Gutenberg University, Mainz (Germany); PRISMA Cluster of Excellence (Germany); Collaboration: P2-Collaboration

2016-07-01

The P2 Experiment aims to measure the weak mixing angle at low Q{sup 2} via the parity violating asymmetry in elastic electron-proton scattering. It will be located at the new Mainz Energy Recovery Superconducting Accelerator (MESA), which will provide a 150 μA beam of alternatingly polarized 150 MeV electrons. While the main asymmetry measurement is performed with integrating Cherenkov detectors, the tracking system is developed in order to determine the average momentum transfer of the electron and to reconstruct individual electron tracks for systematic studies. It will be built using the new technology of High Voltage Monolithic Active Pixel Sensors (HV-MAPS) made of silicon thinned to 50 μm. The main challenge for the tracking system are very high expected particle rates. The expected rate of electrons that are scattered in the liquid hydrogen target and hit the tracking system is of the order 10{sup 5}mm{sup -2}s{sup -1} and is overwhelmed by more than 10{sup 7} mm{sup -2}s{sup -1} bremsstrahlung photons. Each of the tracking layers is envisaged to have a disc-like geometry. They are arranged as two double layers. Since only limited sensor area is affordable, each layer is divided into four segments with about 15 degree azimutal coverage. This layout is presented and motivated by investigations on the expected hit rates and the sensor response.

Ranging behavior relates to welfare indicators pre- and post-range access in commercial free-range broilers.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2018-06-01

Little is known about the effect of accessing an outdoor range on chicken welfare. We tracked individual ranging behavior of 538 mixed-sex Ross 308 chickens on a commercial farm across 4 flocks in winter and summer. Before range access, at 17 to 19 d of age, and post-range access, at 30 to 33 and 42 to 46 d of age in winter and summer flocks respectively, welfare indicators were measured on chickens (pre-range: winter N = 292; summer N = 280; post-range: winter N = 131; summer N = 140), including weight, gait score, dermatitis and plumage condition. Post-ranging autopsies were performed (winter: N = 170; summer: N = 60) to assess breast burn, leg health, and ascites. Fewer chickens accessed the range in winter flocks (32.5%) than summer flocks (82.1%). Few relationships between welfare and ranging were identified in winter, likely due to minimal ranging and the earlier age of post-ranging data collection compared to summer flocks. In summer flocks prior to range access, chickens that accessed the range weighed 4.9% less (P = 0.03) than chickens that did not access the range. Pre-ranging weight, gait score, and overall plumage cover predicted the amount of range use by ranging chickens in summer flocks (P ranging behavior. In summer flocks post-range access, ranging chickens weighed 12.8% less than non-ranging chickens (P range visits were associated with lower weight (P range was associated with lower weight (P range in summer is partly related to changes in broiler chicken welfare. Further investigations are required to determine causation.

Optimisation of the ATLAS Track Reconstruction Software for Run-2

CERN Document Server

Salzburger, Andreas; The ATLAS collaboration

2015-01-01

Track reconstruction is one of the most complex element of the reconstruction of events recorded by ATLAS from collisions delivered by the LHC. It is the most time consuming reconstruction component in high luminosity environments. The flat budget projections for computing resources for Run-2 of the LHC together with the demands of reconstructing higher pile-up collision data at rates more than double those in Run-1 (an increase from 400 Hz to 1 kHz in trigger output) have put stringent requirements on the track reconstruction software. The ATLAS experiment has performed a two year long software campaign which aimed to reduce the reconstruction rate by a factor of three to meet the resource limitations for Run-2: the majority of the changes to achieve this were improvements to the track reconstruction software. The CPU processing time of ATLAS track reconstruction was reduced by more than a factor of three during this campaign without any loss of output information of the track reconstruction. We present the ...

Tracking and Level-1 triggering in the forward region of the ATLAS Muon Spectrometer at sLHC

International Nuclear Information System (INIS)

Bittner, B; Dubbert, J; Kroha, H; Richter, R; Schwegler, P

2012-01-01

In the endcap region of the ATLAS Muon Spectrometer (η > 1) precision tracking and Level-1 triggering are performed by different types of chambers. Monitored Drift Tube chambers (MDT) and Cathode Strip Chambers (CSC) are used for precision tracking, while Thin Gap Chambers (TGC) form the Level-1 muon trigger, selecting muons with high transverse momentum (p T ). When by 2018 the LHC peak luminosity of 10 34 cm −2 s −1 will be increased by a factor of ∼ 2 and by another factor of ∼ 2–2.5 in about a decade from now (''SLHC''), an improvement of both systems, precision tracking and Level-1 triggering, will become mandatory in order to cope with the high rate of uncorrelated background hits (''cavern background'') and to stay below the maximum trigger rate for the muon system, which is in the range of 10–20 % of the 100 kHz rate, allowed for ATLAS. For the Level-1 trigger of the ATLAS Muon Spectrometer this means a stronger suppression of sub-threshold muons in the high-p T trigger as well as a better rejection of tracks not coming from the primary interaction point. Both requirements, however, can only be fulfilled if spatial resolution and angular pointing accuracy of the trigger chambers, in particular of those in the Inner Station of the endcap, are improved by a large factor. This calls for a complete replacement of the currrently used TGC chambers by a new type of trigger chambers with better performance. In parallel, the precision tracking chambers must be replaced by chambers with higher rate capability to be able to cope with the intense cavern background. In this article we present concepts to decisively improve the Level-1 trigger with newly developed trigger chambers, being characterized by excellent spatial resolution, good time resolution and sufficiently short latency. We also present new types of precision chambers, designed to maintain excellent tracking efficiency and spatial resolution in the presence of high levels of uncorrelated

gamma-ray tracking in germanium the backtracking method

CERN Document Server

Marel, J V D

2002-01-01

In the framework of a European TMR network project the concept for a gamma-ray tracking array is being developed for nuclear physics spectroscopy in the energy range of approx 10 keV up to several MeV. The tracking array will consist of a large number of position-sensitive germanium detectors in a spherical geometry around a target. Due to the high segmentation, a Compton scattered gamma-ray will deposit energy in several different segments. A method has been developed to reconstruct the tracks of multiple coincident gamma-rays and to find their initial energies. By starting from the final point the track can be reconstructed backwards to the origin with the help of the photoelectric and Compton cross-sections and the Compton scatter formula. Every reconstructed track is given a figure of merit, thus allowing suppression of wrongly reconstructed tracks and gamma-rays that have scattered out of the detector system. This so-called backtracking method has been tested on simulated events in a shell-like geometry ...

γ-ray tracking in germanium: the backtracking method

International Nuclear Information System (INIS)

Marel, J. van der; Cederwall, B.

2002-01-01

In the framework of a European TMR network project the concept for a γ-ray tracking array is being developed for nuclear physics spectroscopy in the energy range of ∼10 keV up to several MeV. The tracking array will consist of a large number of position-sensitive germanium detectors in a spherical geometry around a target. Due to the high segmentation, a Compton scattered γ-ray will deposit energy in several different segments. A method has been developed to reconstruct the tracks of multiple coincident γ-rays and to find their initial energies. By starting from the final point the track can be reconstructed backwards to the origin with the help of the photoelectric and Compton cross-sections and the Compton scatter formula. Every reconstructed track is given a figure of merit, thus allowing suppression of wrongly reconstructed tracks and γ-rays that have scattered out of the detector system. This so-called backtracking method has been tested on simulated events in a shell-like geometry for germanium and in planar geometries for silicon, germanium and CdTe

Effect of cross-correlation on track-to-track fusion

Science.gov (United States)

Saha, Rajat K.

1994-07-01

Since the advent of target tracking systems employing a diverse mixture of sensors, there has been increasing recognition by air defense system planners and other military system analysts of the need to integrate these tracks so that a clear air picture can be obtained in a command center. A popular methodology to achieve this goal is to perform track-to-track fusion, which performs track-to-track association as well as kinematic state vector fusion. This paper seeks to answer analytically the extent of improvement achievable by means of kinetic state vector fusion when the tracks are obtained from dissimilar sensors (e.g., Radar/ESM/IRST/IFF). It is well known that evaluation of the performance of state vector fusion algorithms at steady state must take into account the effects of cross-correlation between eligible tracks introduced by the input noise which, unfortunately, is often neglected because of added computational complexity. In this paper, an expression for the steady-state cross-covariance matrix for a 2D state vector track-to-track fusion is obtained. This matrix is shown to be a function of the parameters of the Kalman filters associated with the candidate tracks being fused. Conditions for positive definiteness of the cross-covariance matrix have been derived and the effect of positive definiteness on performance of track-to-track fusion is also discussed.

NucliTrack: an integrated nuclei tracking application.

Science.gov (United States)

Cooper, Sam; Barr, Alexis R; Glen, Robert; Bakal, Chris

2017-10-15

Live imaging studies give unparalleled insight into dynamic single cell behaviours and fate decisions. However, the challenge of reliably tracking single cells over long periods of time limits both the throughput and ease with which such studies can be performed. Here, we present NucliTrack, a cross platform solution for automatically segmenting, tracking and extracting features from fluorescently labelled nuclei. NucliTrack performs similarly to other state-of-the-art cell tracking algorithms, but NucliTrack's interactive, graphical interface makes it significantly more user friendly. NucliTrack is available as a free, cross platform application and open source Python package. Installation details and documentation are at: http://nuclitrack.readthedocs.io/en/latest/ A video guide can be viewed online: https://www.youtube.com/watch?v=J6e0D9F-qSU Source code is available through Github: https://github.com/samocooper/nuclitrack. A Matlab toolbox is also available at: https://uk.mathworks.com/matlabcentral/fileexchange/61479-samocooper-nuclitrack-matlab. sam@socooper.com. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

Gas flow rate and powder flow rate effect on properties of laser metal deposited Ti6Al4V

CSIR Research Space (South Africa)

Pityana, S

2013-03-01

Full Text Available . The powder flow rate and the gas flow rate were varied to study their effect on the physical, metallurgical and mechanical properties of the deposits. The physical properties studied are: the track width, the track height and the deposit weight...

SKYWARD: the next generation airborne infrared search and track

Science.gov (United States)

Fortunato, L.; Colombi, G.; Ondini, A.; Quaranta, C.; Giunti, C.; Sozzi, B.; Balzarotti, G.

2016-05-01

Infrared Search and Track systems are an essential element of the modern and future combat aircrafts. Passive automatic search, detection and tracking functions, are key points for silent operations or jammed tactical scenarios. SKYWARD represents the latest evolution of IRST technology in which high quality electro-optical components, advanced algorithms, efficient hardware and software solutions are harmonically integrated to provide high-end affordable performances. Additionally, the reduction of critical opto-mechanical elements optimises weight and volume and increases the overall reliability. Multiple operative modes dedicated to different situations are available; many options can be selected among multiple or single target tracking, for surveillance or engagement, and imaging, for landing or navigation aid, assuring the maximum system flexibility. The high quality 2D-IR sensor is exploited by multiple parallel processing chains, based on linear and non-linear techniques, to extract the possible targets from background, in different conditions, with false alarm rate control. A widely tested track processor manages a large amount of candidate targets simultaneously and allows discriminating real targets from noise whilst operating with low target to background contrasts. The capability of providing reliable passive range estimation is an additional qualifying element of the system. Particular care has been dedicated to the detector non-uniformities, a possible limiting factor for distant targets detection, as well as to the design of the electro-optics for a harsh airborne environment. The system can be configured for LWIR or MWIR waveband according to the customer operational requirements. An embedded data recorder saves all the necessary images and data for mission debriefing, particularly useful during inflight system integration and tuning.

The mechanical behavior of metal alloys with grain size distribution in a wide range of strain rates

Science.gov (United States)

Skripnyak, V. A.; Skripnyak, V. V.; Skripnyak, E. G.

2017-12-01

The paper discusses a multiscale simulation approach for the construction of grain structure of metals and alloys, providing high tensile strength with ductility. This work compares the mechanical behavior of light alloys and the influence of the grain size distribution in a wide range of strain rates. The influence of the grain size distribution on the inelastic deformation and fracture of aluminium and magnesium alloys is investigated by computer simulations in a wide range of strain rates. It is shown that the yield stress depends on the logarithm of the normalized strain rate for light alloys with a bimodal grain distribution and coarse-grained structure.

AUV-Based Plume Tracking: A Simulation Study

Directory of Open Access Journals (Sweden)

Awantha Jayasiri

2016-01-01

Full Text Available This paper presents a simulation study of an autonomous underwater vehicle (AUV navigation system operating in a GPS-denied environment. The AUV navigation method makes use of underwater transponder positioning and requires only one transponder. A multirate unscented Kalman filter is used to determine the AUV orientation and position by fusing high-rate sensor data and low-rate information. The paper also proposes a gradient-based, efficient, and adaptive novel algorithm for plume boundary tracking missions. The algorithm follows a centralized approach and it includes path optimization features based on gradient information. The proposed algorithm is implemented in simulation on the AUV-based navigation system and successful boundary tracking results are obtained.

Quality of Slab Track Construction – Track Alignment Design and Track Geometry

Directory of Open Access Journals (Sweden)

Šestáková Janka

2015-05-01

Full Text Available The slab track superstructure design (without ballast is a perspective construction especially for building tunnels and bridges in the modernized sections of railway tracks in Slovakia. Monitoring of the structure described in this article is focused on the transition areas between standard structure with ballast and slab track construction.

Real time tracking in liver SBRT: comparison of CyberKnife and Vero by planning structure-based γ-evaluation and dose-area-histograms.

Science.gov (United States)

Sothmann, T; Blanck, O; Poels, K; Werner, R; Gauer, T

2016-02-21

The purpose of this study was to evaluate and compare two clinical tracking systems for radiosurgery with regard to their dosimetric and geometrical accuracy in liver SBRT: the robot-based CyberKnife and the gimbal-based Vero. Both systems perform real-time tumour tracking by correlating internal tumour and external surrogate motion. CyberKnife treatment plans were delivered to a high resolution 2D detector array mounted on a 4D motion platform, with the platform simulating (a) tumour motion trajectories extracted from the corresponding CyberKnife predictor log files and (b) the tumour motion trajectories with superimposed baseline-drift. Static reference and tracked dose measurements were compared and dosimetric as well as geometrical uncertainties analyzed by a planning structure-based evaluation. For (a), γ-passing rates inside the CTV (γ-criteria of 1% / 1 mm) ranged from 95% to 100% (CyberKnife) and 98% to 100% (Vero). However, dosimetric accuracy decreases in the presence of the baseline-drift. γ-passing rates for (b) ranged from 26% to 92% and 94% to 99%, respectively; i.e. the effect was more pronounced for CyberKnife. In contrast, the Vero system led to maximum dose deviations in the OAR between  +1.5 Gy to +6.0 Gy (CyberKnife: +0.5 Gy to +3.5 Gy). Potential dose shifts were interpreted as motion-induced geometrical tracking errors. Maximum observed shift ranges were  -1.0 mm to  +0.7 mm (lateral) /-0.6 mm to +0.1 mm (superior-inferior) for CyberKnife and  -0.8 mm to +0.2 mm /-0.8 mm to +0.4 mm for Vero. These values illustrate that CyberKnife and Vero provide high precision tracking of regular breathing patterns. Even for the modified motion trajectory, the obtained dose distributions appear to be clinical acceptable with regard to literature QA γ-criteria of 3% / 3 mm.

An Algorithm to Automate Yeast Segmentation and Tracking

Science.gov (United States)

Doncic, Andreas; Eser, Umut; Atay, Oguzhan; Skotheim, Jan M.

2013-01-01

Our understanding of dynamic cellular processes has been greatly enhanced by rapid advances in quantitative fluorescence microscopy. Imaging single cells has emphasized the prevalence of phenomena that can be difficult to infer from population measurements, such as all-or-none cellular decisions, cell-to-cell variability, and oscillations. Examination of these phenomena requires segmenting and tracking individual cells over long periods of time. However, accurate segmentation and tracking of cells is difficult and is often the rate-limiting step in an experimental pipeline. Here, we present an algorithm that accomplishes fully automated segmentation and tracking of budding yeast cells within growing colonies. The algorithm incorporates prior information of yeast-specific traits, such as immobility and growth rate, to segment an image using a set of threshold values rather than one specific optimized threshold. Results from the entire set of thresholds are then used to perform a robust final segmentation. PMID:23520484

Thermal neutron detection by means of an organic solid-state track detector

International Nuclear Information System (INIS)

Doerschel, B.; Streubel, G.

1979-01-01

Thermal neutrons can be detected by means of organic solid-state track detectors if they are combined with radiators in which charged secondary particles are produced in neutron interaction processes. The secondary particles can produce etchable tracks in the detector material. For thermal neutron fluence determination from the track densities, the thermal neutron sensitivity was calculated for cellulose triacetate detectors with LiF radiators, taking into account energy and angular distribution of the alpha particles produced in the LiF radiator. This value is in good agreement with the sensitivity measured during irradiation in different neutron fields if corrections are considered the production of etchable or visuable tracks. Measuring range and measuring accuracy meet the requirements of thermal neutron detection in personnel dosimetry. Possibilities of extending the measuring range are discussed. (author)

Investigation of tracking systems properties in CAVE-type virtual reality systems

Science.gov (United States)

Szymaniak, Magda; Mazikowski, Adam; Meironke, Michał

2017-08-01

In recent years, many scientific and industrial centers in the world developed a virtual reality systems or laboratories. One of the most advanced solutions are Immersive 3D Visualization Lab (I3DVL), a CAVE-type (Cave Automatic Virtual Environment) laboratory. It contains two CAVE-type installations: six-screen installation arranged in a form of a cube, and four-screen installation, a simplified version of the previous one. The user feeling of "immersion" and interaction with virtual world depend on many factors, in particular on the accuracy of the tracking system of the user. In this paper properties of the tracking systems applied in I3DVL was investigated. For analysis two parameters were selected: the accuracy of the tracking system and the range of detection of markers by the tracking system in space of the CAVE. Measurements of system accuracy were performed for six-screen installation, equipped with four tracking cameras for three axes: X, Y, Z. Rotation around the Y axis was also analyzed. Measured tracking system shows good linear and rotating accuracy. The biggest issue was the range of the monitoring of markers inside the CAVE. It turned out, that the tracking system lose sight of the markers in the corners of the installation. For comparison, for a simplified version of CAVE (four-screen installation), equipped with eight tracking cameras, this problem was not occur. Obtained results will allow for improvement of cave quality.

Shifts in diversification rates and host jump frequencies shaped the diversity of host range among Sclerotiniaceae fungal plant pathogens.

Science.gov (United States)

Navaud, Olivier; Barbacci, Adelin; Taylor, Andrew; Clarkson, John P; Raffaele, Sylvain

2018-03-01

The range of hosts that a parasite can infect in nature is a trait determined by its own evolutionary history and that of its potential hosts. However, knowledge on host range diversity and evolution at the family level is often lacking. Here, we investigate host range variation and diversification trends within the Sclerotiniaceae, a family of Ascomycete fungi. Using a phylogenetic framework, we associate diversification rates, the frequency of host jump events and host range variation during the evolution of this family. Variations in diversification rate during the evolution of the Sclerotiniaceae define three major macro-evolutionary regimes with contrasted proportions of species infecting a broad range of hosts. Host-parasite cophylogenetic analyses pointed towards parasite radiation on distant hosts long after host speciation (host jump or duplication events) as the dominant mode of association with plants in the Sclerotiniaceae. The intermediate macro-evolutionary regime showed a low diversification rate, high frequency of duplication events and the highest proportion of broad host range species. Our findings suggest that the emergence of broad host range fungal pathogens results largely from host jumps, as previously reported for oomycete parasites, probably combined with low speciation rates. These results have important implications for our understanding of fungal parasites evolution and are of particular relevance for the durable management of disease epidemics. © 2018 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Super-ranging. A new ranging strategy in European badgers.

Directory of Open Access Journals (Sweden)

Aoibheann Gaughran

Full Text Available We monitored the ranging of a wild European badger (Meles meles population over 7 years using GPS tracking collars. Badger range sizes varied seasonally and reached their maximum in June, July and August. We analysed the summer ranging behaviour, using 83 home range estimates from 48 individuals over 6974 collar-nights. We found that while most adult badgers (males and females remained within their own traditional social group boundaries, several male badgers (on average 22% regularly ranged beyond these traditional boundaries. These adult males frequently ranged throughout two (or more social group's traditional territories and had extremely large home ranges. We therefore refer to them as super-rangers. While ranging across traditional boundaries has been recorded over short periods of time for extraterritorial mating and foraging forays, or for pre-dispersal exploration, the animals in this study maintained their super-ranges from 2 to 36 months. This study represents the first time such long-term extra-territorial ranging has been described for European badgers. Holding a super-range may confer an advantage in access to breeding females, but could also affect local interaction networks. In Ireland & the UK, badgers act as a wildlife reservoir for bovine tuberculosis (TB. Super-ranging may facilitate the spread of disease by increasing both direct interactions between conspecifics, particularly across social groups, and indirect interactions with cattle in their shared environment. Understanding super-ranging behaviour may both improve our understanding of tuberculosis epidemiology and inform future control strategies.

A practical approach to tramway track condition monitoring: vertical track defects detection and identification using time-frequency processing technique

Directory of Open Access Journals (Sweden)

Bocz Péter

2018-03-01

Full Text Available This paper presents an automatic method for detecting vertical track irregularities on tramway operation using acceleration measurements on trams. For monitoring of tramway tracks, an unconventional measurement setup is developed, which records the data of 3-axes wireless accelerometers mounted on wheel discs. Accelerations are processed to obtain the vertical track irregularities to determine whether the track needs to be repaired. The automatic detection algorithm is based on time–frequency distribution analysis and determines the defect locations. Admissible limits (thresholds are given for detecting moderate and severe defects using statistical analysis. The method was validated on frequented tram lines in Budapest and accurately detected severe defects with a hit rate of 100%, with no false alarms. The methodology is also sensitive to moderate and small rail surface defects at the low operational speed.

Proposed FPGA based tracking for a Level-1 track trigger at CMS for the HL-LHC

CERN Document Server

Pozzobon, Nicola

2014-01-01

The High Luminosity LHC (HL-LHC) is expected to deliver a luminosity in excess of $5\\times10^{34}$ cm$^{-2}$/s. The high event rate places stringent requirements on the trigger system. A key component of the CMS upgrade for the HL-LHC is a track trigger system which will identify tracks with transverse momenta above 2 GeV already at the first-level trigger within 5 $\\mu$s. This presentation will discuss a proposed track finding and fitting based on the tracklet based approach implemented on FPGAs. Tracklets are formed from pairs of hits in nearby layers in the detector and used in a road search. Summary Fast pattern recognition in Silicon trackers for triggering has often made use of Associative Memories for the pattern recognition step. We propose an alternative approach to solving the pattern recognition and track fitting problem for the upgraded CMS tracker for the HL-LHC operation. We make use of the trigger primitives,stubs, from the tracker. The stubs are formed from pairs of hits in sensors separated r...

A Novel Generic Framework for Track Fitting in Complex Detector Systems

OpenAIRE

Höppner, C.; Neubert, S.; Ketzer, B.; Paul, S.

2009-01-01

This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices th...

L1Track: A fast Level 1 track trigger for the ATLAS high luminosity upgrade

International Nuclear Information System (INIS)

Cerri, Alessandro

2016-01-01

With the planned high-luminosity upgrade of the LHC (HL-LHC), the ATLAS detector will see its collision rate increase by approximately a factor of 5 with respect to the current LHC operation. The earliest hardware-based ATLAS trigger stage (“Level 1”) will have to provide a higher rejection factor in a more difficult environment: a new improved Level 1 trigger architecture is under study, which includes the possibility of extracting with low latency and high accuracy tracking information in time for the decision taking process. In this context, the feasibility of potential approaches aimed at providing low-latency high-quality tracking at Level 1 is discussed. - Highlights: • HL-LH requires highly performing event selection. • ATLAS is studying the implementation of tracking at the very first trigger level. • Low latency and high-quality seem to be achievable with dedicated hardware and adequate detector readout architecture.

Trigger and electronics issues for scintillating fiber tracking

International Nuclear Information System (INIS)

Baumbaugh, A.E.

1994-01-01

Scintillating Fiber technology has made great advances and has demonstrated great promise for high speed charged particle tracking and triggering. The small detector sizes and fast scintillation floors available, make them very promising for use at high luminosity experiments at today's and tomorrow's colliding and fixed target experiments where high rate capability is essential. This paper will discuss some of the system aspects which should be considered by anyone attempting to design a scintillating fiber tracking system and high speed tracking trigger. As the reader will see, seemingly simple decisions can have far reaching effects on overall system performance

A Novel Hybrid Mental Spelling Application Based on Eye Tracking and SSVEP-Based BCI

Directory of Open Access Journals (Sweden)

Piotr Stawicki

2017-04-01

Full Text Available Steady state visual evoked potentials (SSVEPs-based Brain-Computer interfaces (BCIs, as well as eyetracking devices, provide a pathway for re-establishing communication for people with severe disabilities. We fused these control techniques into a novel eyetracking/SSVEP hybrid system, which utilizes eye tracking for initial rough selection and the SSVEP technology for fine target activation. Based on our previous studies, only four stimuli were used for the SSVEP aspect, granting sufficient control for most BCI users. As Eye tracking data is not used for activation of letters, false positives due to inappropriate dwell times are avoided. This novel approach combines the high speed of eye tracking systems and the high classification accuracies of low target SSVEP-based BCIs, leading to an optimal combination of both methods. We evaluated accuracy and speed of the proposed hybrid system with a 30-target spelling application implementing all three control approaches (pure eye tracking, SSVEP and the hybrid system with 32 participants. Although the highest information transfer rates (ITRs were achieved with pure eye tracking, a considerable amount of subjects was not able to gain sufficient control over the stand-alone eye-tracking device or the pure SSVEP system (78.13% and 75% of the participants reached reliable control, respectively. In this respect, the proposed hybrid was most universal (over 90% of users achieved reliable control, and outperformed the pure SSVEP system in terms of speed and user friendliness. The presented hybrid system might offer communication to a wider range of users in comparison to the standard techniques.

FTK: a Fast Track Trigger for ATLAS

International Nuclear Information System (INIS)

Anderson, J; Auerbach, B; Blair, R; Andreani, A; Andreazza, A; Citterio, M; Annovi, A; Beretta, M; Castegnaro, A; Atkinson, M; Cavaliere, V; Chang, P; Bevacqua, V; Crescioli, F; Blazey, G; Bogdan, M; Boveia, A; Canelli, F; Cheng, Y; Cervigni, F

2012-01-01

We describe the design and expected performance of a the Fast Tracker Trigger (FTK) system for the ATLAS detector at the Large Hadron Collider. The FTK is a highly parallel hardware system designed to operate at the Level 1 trigger output rate. It is designed to provide global tracks reconstructed in the inner detector with resolution comparable to the full offline reconstruction as input of the Level 2 trigger processing. The hardware system is based on associative memories for pattern recognition and fast FPGAs for track reconstruction. The FTK is expected to dramatically improve the performance of track based isolation and b-tagging with little to no dependencies of pile-up interactions.

Pamela tracking system status report

CERN Document Server

Taccetti, F; Bonechi, L; Bongi, M; Boscherini, M; Castellini, G; D'Alessandro, R; Gabbanini, A; Grandi, M; Papini, P; Piccardi, S; Ricciarini, S; Spillantini, P; Straulino, S; Tesi, M; Vannuccini, E

2002-01-01

The Pamela apparatus will be launched at the end of 2002 on board of the Resurs DK Russian satellite. The tracking system, composed of six planes of silicon sensors inserted inside a permanent magnetic field was intensively tested during these last years. Results of tests have shown a good signal-to-noise ratio and an excellent spatial resolution, which should allow to measure the antiproton flux in an energy range from 80 MeV up to 190 GeV. The production of the final detector modules is about to start and mechanical and thermal tests on the tracking tower are being performed according to the specifications of the Russian launcher and satellite.

Cardiac surgery fast-track treatment in a postanesthetic care unit: six-month results of the Leipzig fast-track concept.

Science.gov (United States)

Ender, Joerg; Borger, Michael Andrew; Scholz, Markus; Funkat, Anne-Kathrin; Anwar, Nadeem; Sommer, Marcus; Mohr, Friedrich Wilhelm; Fassl, Jens

2008-07-01

The authors compared the safety and efficacy of a newly developed fast-track concept at their center, including implementation of a direct admission postanesthetic care unit, to standard perioperative management. All fast-track patients treated within the first 6 months of implementation of our direct admission postanesthetic care unit were matched via propensity scores and compared with a historical control group of patients who underwent cardiac surgery prior to fast-track implementation. A total of 421 fast-track patients were matched successfully to 421 control patients. The two groups of patients had a similar age (64 +/- 13 vs. 64 +/- 12 yr for fast-track vs. control, P = 0.45) and European System for Cardiac Operative Risk Evaluation-predicted risk of mortality (4.8 +/- 6.1% vs. 4.6 +/- 5.1%, P = 0.97). Fast-track patients had significantly shorter times to extubation (75 min [45-110] vs. 900 min [600-1140]), as well as shorter lengths of stay in the postanesthetic or intensive care unit (4 h [3.0-5] vs. 20 h [16-25]), intermediate care unit (21 h [17-39] vs. 26 h [19-49]), and hospital (10 days [8-12] vs. 11 days [9-14]) (expressed as median and interquartile range, all P operations.

Fission distribution measurements of Atucha's fuel pellets with solid state track detectors

International Nuclear Information System (INIS)

Ricabarra, M.D. Bovisio de; Waisman, Dina.

1979-08-01

Distribution of fissions in a UO 2 rod has been measured by means of solid state detectors. Mica muscovite and Makrofol-N detectors were used in the experiment. The merits of mica muscovite relative to the Makrofol-N for the detection of fission fragments have been verified. However both fission track detectors closely agree (0,5%) in the final fission distribution of the UO 2 rod. Sensitivity of the detectors shows to be linear in the range between 50.000and 360.000 fission tracks per square centimeter. Due to the high spatial resolution this method is better than any other technique. Determination were made in UO 2 pellets similar to the fuel element of the Atucha reactor. The average fission rate in the rod has been measured within 0,8% error, and provides an accurate determination for the distribution of fissions in the rod wich is needed for the determination of energy liberated per fission in the natural uranium rod.(author) [es

Fast regional readout CMOS Image Sensor for dynamic MLC tracking

Science.gov (United States)

Zin, H.; Harris, E.; Osmond, J.; Evans, P.

2014-03-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ~400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Fast regional readout CMOS image sensor for dynamic MLC tracking

International Nuclear Information System (INIS)

Zin, H; Harris, E; Osmond, J; Evans, P

2014-01-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ∼400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Fast neutron irradiation effects on CR-39 nuclear track detector for dosimetric applications

International Nuclear Information System (INIS)

Kader, M.H.

2005-01-01

The effect of neutron irradiation on the dosimetric properties of CR-39 solid-state nuclear track detector have been investigated. CR-39 samples were irradiated with neutrons of energies follow a Maxwellian distribution centered about 2 MeV. These samples were irradiated with different doses in the range 0.1-1 Sv. The background and track density were measured as a function of etching time. In addition, the dependence of sensitivity of CR-39 detector on the neutrons dose has been investigated. The results show that the Sensitivity started to increase at 0.4 Sv neutrons dose, so this sample were chosen to be a subject for further study to investigate the effect of gamma dose on its properties. The sample irradiated with 0.4 Sv were exposed to different doses of gamma rays at levels between 10 and 80 kGy. The effect of gamma doses on the bulk etching rate VB, the track diameter and the sensitivity of the CR-39 samples was investigated. The results show that the dosimetric properties of CR-39 SSNTD are greatly affected by both neutron and gamma irradiation

Comparison of the measurement of heart rate in adult free-range chickens (Gallus domesticus) by auscultation and electrocardiography.

Science.gov (United States)

Smith, C F; Gavaghan, B J; McSweeney, D; Powell, V; Lisle, A

2014-12-01

To compare the heart rates of adult free-range chickens (Gallus domesticus) measured by auscultation with a stethoscope with those measured simultaneously using electrocardiography (ECG). With each bird in a standing position, estimation of the heart rate was performed by placing a mark on paper for every 4 beats for roosters and 8 beats for hens as detected by auscultation over 30 s, while simultaneous ECG was performed. Heart rates measured by auscultation showed a high correlation (r = 0.97) with those measured by ECG. There was a high correlation between the heart rates of adult free-range chickens measured by auscultation with a stethoscope and those measured simultaneously using ECG. © 2014 Australian Veterinary Association.

Applications for Track-etched Templates and Films

International Nuclear Information System (INIS)

Ferain, E.

2006-01-01

Track etching technology of first generation is mainly used for the production of self-supported membranes made of polycarbonate (PC) or polyethylene terephthalate (PET) with randomly distributed pores. Typical membrane thickness is between 10 and 20 microns and pore size is in the range 0,1 μm to 10 μm. Second generation track etching technology overcomes many of limitations and offers new advantages : true nanopores down to 10 nm with well-controlled pore shape in a large range of pore densities, use of polymer (polyimide-PI) resistant to high temperature (up to 430 degree), ability to track etch a thin polymeric layer deposited on a substrate (such as glass, quartz, silicon, oxides, ...) and ability to confine nanopores into zones as small as 10 micron square (patterning process). This second generation technology, when applied to larger pore size, also contributes to a better membrane with potential benefits as e.g. a more precise cut-off. Another feature of the second generation technology is the patterning of the polymer layers - i.e. the nanopores can be grown in defined areas of the polymer layers. Smart membranes are used as separation barriers and flow controllers in devices such as chemical and biochemical sensors and analysers (lab on a chip, microtitre plates, ...). For example, a specific track etched membrane has been designed to be used as a selective separation barrier in a project intends to develop, improve and validate an efficient reliable bioartificial pancreas for human application. A variety of materials (metals, semiconductors, oxides, heterostructures) can be deposited into the pores as nanowires or nanotubes; these structures can be produced with over wide range of aspect ratios with excellent shape control, and can be either used in-situ or easily harvested by simple chemical dissolution

An algorithm to automate yeast segmentation and tracking.

Directory of Open Access Journals (Sweden)

Andreas Doncic

Full Text Available Our understanding of dynamic cellular processes has been greatly enhanced by rapid advances in quantitative fluorescence microscopy. Imaging single cells has emphasized the prevalence of phenomena that can be difficult to infer from population measurements, such as all-or-none cellular decisions, cell-to-cell variability, and oscillations. Examination of these phenomena requires segmenting and tracking individual cells over long periods of time. However, accurate segmentation and tracking of cells is difficult and is often the rate-limiting step in an experimental pipeline. Here, we present an algorithm that accomplishes fully automated segmentation and tracking of budding yeast cells within growing colonies. The algorithm incorporates prior information of yeast-specific traits, such as immobility and growth rate, to segment an image using a set of threshold values rather than one specific optimized threshold. Results from the entire set of thresholds are then used to perform a robust final segmentation.

Denudation rates and tectonic geomorphology of the Spanish Betic Cordillera

Science.gov (United States)

Bellin, N.; Vanacker, V.; Kubik, P. W.

2014-03-01

The tectonic control on landscape morphology and long-term denudation is largely documented for settings with high uplift rates. Relatively little is known about the rates of geomorphic response in areas of low tectonic uplift. Here, we evaluate spatial variations in denudation of the Spanish Betic Cordillera based on cosmogenic 10Be-derived denudation rates. Denudation rates are compared to published data on rock uplift and exhumation of the Betic Cordillera to evaluate steady-state topography. The spatial patterns of catchment-wide denudation rates (n=20) are then analysed together with topographic metrics of hillslope and channel morphology. Catchments draining the Betic ranges have relatively low denudation rates (64±54 mm kyr), but also show large variation as they range from 14 to 246 mm kyr-1. Catchment-wide denudation is linearly proportional to the mean hillslope gradient and local relief. Despite large spatial variation in denudation, the magnitude and spatial pattern of denudation rates are generally consistent with longer-term local uplift rates derived from elevated marine deposits, fission-track measurements and vertical fault slip rates. This might be indicative of a steady-state topography where rock uplift is balanced by denudation.

Track-based event recognition in a realistic crowded environment

Science.gov (United States)

van Huis, Jasper R.; Bouma, Henri; Baan, Jan; Burghouts, Gertjan J.; Eendebak, Pieter T.; den Hollander, Richard J. M.; Dijk, Judith; van Rest, Jeroen H.

2014-10-01

Automatic detection of abnormal behavior in CCTV cameras is important to improve the security in crowded environments, such as shopping malls, airports and railway stations. This behavior can be characterized at different time scales, e.g., by small-scale subtle and obvious actions or by large-scale walking patterns and interactions between people. For example, pickpocketing can be recognized by the actual snatch (small scale), when he follows the victim, or when he interacts with an accomplice before and after the incident (longer time scale). This paper focusses on event recognition by detecting large-scale track-based patterns. Our event recognition method consists of several steps: pedestrian detection, object tracking, track-based feature computation and rule-based event classification. In the experiment, we focused on single track actions (walk, run, loiter, stop, turn) and track interactions (pass, meet, merge, split). The experiment includes a controlled setup, where 10 actors perform these actions. The method is also applied to all tracks that are generated in a crowded shopping mall in a selected time frame. The results show that most of the actions can be detected reliably (on average 90%) at a low false positive rate (1.1%), and that the interactions obtain lower detection rates (70% at 0.3% FP). This method may become one of the components that assists operators to find threatening behavior and enrich the selection of videos that are to be observed.

Application of solid state nuclear track detectors in radiation protection

International Nuclear Information System (INIS)

Ramachandran, T.V.; Subba Ramu, M.C.; Mishra, U.C.

1989-01-01

This article reviews the current status of the application of nuclear track detectors with emphasis on recent developments in the field of radiation protection. Track etch detectors have been used for the measurements of low level radiation in the environment, fast neutron and radon daughter inhalation dose. Recent developments in the field of dosimetry seem to be promising. In fast neutron dosimetry, track etch detectors can be used without inclusion of fissile materials by using the electrochemical etching technique. These detectors can provide important information in the energy range upto 250 keV. Survey of this range of energy with TLD is difficult because they are extremely energy dependent and over-respond to low energy neutrons. Measurement of radon using track detectors can help to lower the cost of the radon dosimeters. Certain detectors are sensitive to alpha particles from radon and their progeny. Higher sensitivity permits their use in a passive type of personnel dosimeter, which does not require the troublesome aspects of air sampling for the collection of radon daughter samples. (author), 38 refs., 8 tabs., 12 figs

X-γ dose rate continuous monitor with wide range based on single-chip microcomputer

International Nuclear Information System (INIS)

Wu Debo; Ling Qiu; Guo Lanying; Yang Binhua

2007-01-01

This paper describes a concept about circuit designing of X-γ dose rate continuous monitor with wide range based on single-chip microcomputer, and also presents the design procedure of hardware and software, and gives several methods for solving the design procedure of hardware and software with emphasis. (authors)

Patient tracking system

International Nuclear Information System (INIS)

Chapman, L.J.; Hakimi, R.; Salehi, D.; McCord, T.; Zionczkowski, B.; Churchill, R.

1987-01-01

This exhibit describes computer applications in monitoring patient tracking in radiology and the collection of management information (technologist productivity, patient waiting times, repeat rate, room utilization) and quality assurance information. An analysis of the reports that assist in determining staffing levels, training needs, and patient scheduling is presented. The system is designed to require minimal information input and maximal information output to assist radiologists, quality assurance coordinators, and management personnel in departmental operations

Track-Etched Magnetic Micropores for Immunomagnetic Isolation of Pathogens

Science.gov (United States)

Muluneh, Melaku; Shang, Wu

2014-01-01

A microfluidic chip is developed to selectively isolate magnetically tagged cells from heterogeneous suspensions, the track-etched magnetic micropore (TEMPO) filter. The TEMPO consists of an ion track-etched polycarbonate membrane coated with soft magnetic film (Ni20Fe80). In the presence of an applied field, provided by a small external magnet, the filter becomes magnetized and strong magnetic traps are created along the edges of the micropores. In contrast to conventional microfluidics, fluid flows vertically through the porous membrane allowing large flow rates while keeping the capture rate high and the chip compact. By utilizing track-etching instead of conventional semiconductor fabrication, TEMPOs can be fabricated with microscale pores over large areas A > 1 cm2 at little cost ( 500 at a flow rate of Φ = 5 mL h−1. Furthermore, the large density of micropores (ρ = 106 cm−2) allows the TEMPO to sort E. coli from unprocessed environmental and clinical samples, as the blockage of a few pores does not significantly change the behavior of the device. PMID:24535921

Combining Charge Couple Devices and Rate Sensors for the Feedforward Control System of a Charge Coupled Device Tracking Loop.

Science.gov (United States)

Tang, Tao; Tian, Jing; Zhong, Daijun; Fu, Chengyu

2016-06-25

A rate feed forward control-based sensor fusion is proposed to improve the closed-loop performance for a charge couple device (CCD) tracking loop. The target trajectory is recovered by combining line of sight (LOS) errors from the CCD and the angular rate from a fiber-optic gyroscope (FOG). A Kalman filter based on the Singer acceleration model utilizes the reconstructive target trajectory to estimate the target velocity. Different from classical feed forward control, additive feedback loops are inevitably added to the original control loops due to the fact some closed-loop information is used. The transfer function of the Kalman filter in the frequency domain is built for analyzing the closed loop stability. The bandwidth of the Kalman filter is the major factor affecting the control stability and close-loop performance. Both simulations and experiments are provided to demonstrate the benefits of the proposed algorithm.

Fast track trigger processor for the OPAL detector at LEP

Energy Technology Data Exchange (ETDEWEB)

Carter, A A; Carter, J R; Ward, D R; Heuer, R D; Jaroslawski, S; Wagner, A

1986-09-20

A fast hardware track trigger processor being built for the OPAL experiment is described. The processor will analyse data from the central drift chambers of OPAL to determine whether any tracks come from the interaction region, and thereby eliminate background events. The processor will find tracks over a large angular range, vertical strokecos thetavertical stroke < or approx. 0.95. The design of the processor is described, together with a brief account of its hardware implementation for OPAL. The results of feasibility studies are also presented.

Tracking errors in a prototype real-time tumour tracking system

International Nuclear Information System (INIS)

Sharp, Gregory C; Jiang, Steve B; Shimizu, Shinichi; Shirato, Hiroki

2004-01-01

In motion-compensated radiation therapy, radio-opaque markers can be implanted in or near a tumour and tracked in real-time using fluoroscopic imaging. Tracking these implanted markers gives highly accurate position information, except when tracking fails due to poor or ambiguous imaging conditions. This study investigates methods for automatic detection of tracking errors, and assesses the frequency and impact of tracking errors on treatments using the prototype real-time tumour tracking system. We investigated four indicators for automatic detection of tracking errors, and found that the distance between corresponding rays was most effective. We also found that tracking errors cause a loss of gating efficiency of between 7.6 and 10.2%. The incidence of treatment beam delivery during tracking errors was estimated at between 0.8% and 1.25%

Robust tracking control of uncertain Duffing-Holmes control systems

International Nuclear Information System (INIS)

Sun, Y.-J.

2009-01-01

In this paper, the notion of virtual stabilizability for dynamical systems is introduced and the virtual stabilizability of uncertain Duffing-Holmes control systems is investigated. Based on the time-domain approach with differential inequality, a tracking control is proposed such that the states of uncertain Duffing-Holmes control system track the desired trajectories with any pre-specified exponential decay rate and convergence radius. Moreover, we present an algorithm to find such a tracking control. Finally, a numerical example is provided to illustrate the use of the main results.

A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas (Mammalia, Didelphidae in the Atlantic forest of south-eastern Brazil

Directory of Open Access Journals (Sweden)

Edsel Amorim Moraes Junior

2005-03-01

Full Text Available From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905 (three males and four females were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points, and minimum convex polygon (MCP methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100% ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95% were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night than females (335.1 m/night (t test, t = 3.609, p = 0.001. We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less. Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817.No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905 (três machos e quatro fêmeas foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações e polígono mínimo convexo (PMC, com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100% variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95% foram 4-10,9 ha para machos e 1,3-5,9 ha para f

Feasibility studies for a wireless 60 GHz tracking detector readout

CERN Document Server

Dittmeier, Sebastian; Soltveit, Hans Kristian; Wiedner, Dirk

2016-01-01

The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the in...

Charged Particle Tracking and Vertex Detection Group summary report

International Nuclear Information System (INIS)

Hanson, G.; Meyer, D.

1984-09-01

Charged particle tracking is essential in order to investigate the new physics expected at the SSC. The Tracking Group studied radiation damage and rate limitations to tracking devices, vertex detectors, and central tracking. The Group concluded that silicon strips and large wire tracking chambers with small cells can probably survive at the design luminosity of 10 33 cm -2 sec -1 ; however, the presently designed electronics for silicon strip vertex detectors can withstand a luminosity of only 10 31 cm -2 sec -1 . Wire chambers at a radius of less than about 25 cm can withstand a luminosity of less than or equal to 10 32 cm -2 sec -1 only. Actual tracking and pattern recognition in central tracking chambers at a luminosity of 10 33 cm -2 sec -1 will be very difficult because of multiple interactions within the resolving time of the chambers; detailed simulations are needed in order to decide whether tracking is indeed possible at this luminosity. Scintillating glass fibers are an interesting possibility both for vertex detectors and for central trackers, but much research and development is still needed both on the fibers themselves and on the readout

Surfactant-enhanced control of track-etch pore morphology

International Nuclear Information System (INIS)

Apel', P.Yu.; Blonskaya, I.V.; Didyk, A.Yu.; Dmitriev, S.N.; Orelovich, O.L.; Samojlova, L.I.; Vutsadakis, V.A.; Root, D.

2000-01-01

The influence of surfactants on the process of chemical development of ion tracks in polymers is studied. Based on the experimental data, a mechanism of the surfactant effect on the track-etch pore morphology is proposed. In the beginning of etching the surfactant is adsorbed on the surface and creates a layer that is quasi-solid and partially protects the surface from the etching agent. However, some etchant molecules diffuse through the barrier and react with the polymer surface. This results in the formation of a small hole at the entrance to the ion track. After the hole has attained a few annometers in diameter, the surfactant molecules penetrate into the track and cover its walls. Further diffusion of the surfactant into the growing pore is hindered. The adsorbed surfactant layer is not permeable for large molecules. In contrast, small alkali molecules and water molecules diffuse into the track and provide the etching process enlarging the pore. At this stage the transport of the surfactant into the pore channel can proceed only due to the lateral diffusion in the adsorbed layer. The volume inside the pore is free of surfactant molecules and grows at a higher rate than pore entrance. After a more prolonged etching the bottle-like (or 'cigar-like') pore channels are formed. The bottle-like shape of the pore channels depends on the etching conditions such as alkali and surfactant concentration, temperature, and type of the surfactant. The use of surfactants enables one to produce track-etch membranes with improved flow rate characteristics compared with those having cylindrical pores with the same nominal pore diameters

Managing Clutter in a High Pulse Rate Echolocation System

Directory of Open Access Journals (Sweden)

Jacob Isbell

2018-03-01

Full Text Available The use of echolocation for navigating in dense, cluttered environments is a challenge due to the need for rapid sampling of nearby objects in the face of delayed echoes from distant objects. In the wild, echolocating bats frequently encounter this situation when leaving the roost or while hunting. If long-delay echoes from a distant object are received after the next pulse is sent out, these “aliased” echoes appear as close-range phantom objects. Little is known about how bats cope with these situations. In this work, we demonstrate a novel strategy to manage aliasing in cases where a single target is actively being tracked at close range. This paper presents three reactive strategies for a high pulse-rate sonar system to combat aliased echoes: (1 changing the interpulse interval to move the aliased echoes away in time from the tracked target, (2 changing positions to create a geometry without aliasing, and (3 a phase-based, transmission beam-shaping strategy to illuminate the target and not the aliasing object.

Automated Storm Tracking and the Lightning Jump Algorithm Using GOES-R Geostationary Lightning Mapper (GLM) Proxy Data

Science.gov (United States)

Schultz, Elise; Schultz, Christopher Joseph; Carey, Lawrence D.; Cecil, Daniel J.; Bateman, Monte

2016-01-01

This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system's performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system's performance is evaluated with adjustments to parameter sensitivity. The system's performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of lightning jump strength) and flash rate threshold influenced the system's performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the lightning jump system.

Target Tracking of a Linear Time Invariant System under Irregular Sampling

Directory of Open Access Journals (Sweden)

Jin Xue-Bo

2012-11-01

Full Text Available Due to event-triggered sampling in a system, or maybe with the aim of reducing data storage, tracking many applications will encounter irregular sampling time. By calculating the matrix exponential using an inverse Laplace transform, this paper transforms the irregular sampling tracking problem to the problem of tracking with time-varying parameters of a system. Using the common Kalman filter, the developed method is used to track a target for the simulated trajectory and video tracking. The results of simulation experiments have shown that it can obtain good estimation performance even at a very high irregular rate of measurement sampling time.

The design and construction of the ZEUS central tracking detector

Energy Technology Data Exchange (ETDEWEB)

Foster, B.; Malos, J.; Saxon, D.H.; Clark, D.E.; Jamdagni, A.K.; Markou, C.; Miller, D.B.; Miller, D.G.; Toudup, L.W.; Auty, C.G.; Blair, G.A.; Brooks, C.B.; Cashmore, R.J.; Hanford, A.T.; Harnew, N.; Holmes, A.R.; Linford, W.; Martin, N.C.; McArthur, I.C.; Nash, J.; Nobbs, K.N.; Wastie, R.L.; Williams, M.T.; Wilson, F.F.; Wilson, R.D.; Hart, J.C.; Hatley, R.W.; Hiddleston, J.W.; Gibson, M.D.; McCubbin, N.A.; Middleton, A.; Morrissey, M.C.; Morrow, D.; O' Brien, P.; Payne, B.T.; Roberts, J.C.H.; Shaw, T.B.; Sinclair, C.K.; Wallis, E.W.G.; White, D.J.; Yeo, K.L.; Bullock, F.W.; Dumper, J.; Fraser, T.J.; Hayes, D.; Jones, T.W.; Strachan, D.E.; Vine, I.A. (H.H. Wills Physics Lab., Univ. of Bristol (United Kingdom) Dept. of Physics and Astronomy, Univ. of Glasgow (United Kingdom) Blackett Lab., Physics Dept., Imperial Coll., London (United Kingdom) Dept. of Physics, Nuclear Physics Lab., Univ. of Oxford (United Kingdom) Rutherford Appleton Lab., Chilton (United Kingdom) Dept. of Physics an

1994-01-15

The mechanical, electrical and electronic design and construction of the ZEUS central tracking detector are described, together with the chamber monitoring and environmental control. This cylindrical drift chamber is designed for track reconstruction, electron identification and fast event triggering in a high beam-crossing rate, high magnetic field application. (orig.)

Feature Tracking for High Speed AFM Imaging of Biopolymers.

Science.gov (United States)

Hartman, Brett; Andersson, Sean B

2018-03-31

The scanning speed of atomic force microscopes continues to advance with some current commercial microscopes achieving on the order of one frame per second and at least one reaching 10 frames per second. Despite the success of these instruments, even higher frame rates are needed with scan ranges larger than are currently achievable. Moreover, there is a significant installed base of slower instruments that would benefit from algorithmic approaches to increasing their frame rate without requiring significant hardware modifications. In this paper, we present an experimental demonstration of high speed scanning on an existing, non-high speed instrument, through the use of a feedback-based, feature-tracking algorithm that reduces imaging time by focusing on features of interest to reduce the total imaging area. Experiments on both circular and square gratings, as well as silicon steps and DNA strands show a reduction in imaging time by a factor of 3-12 over raster scanning, depending on the parameters chosen.

Free-ranging farm cats: home range size and predation on a livestock unit in Northwest Georgia.

Science.gov (United States)

Kitts-Morgan, Susanna E; Caires, Kyle C; Bohannon, Lisa A; Parsons, Elizabeth I; Hilburn, Katharine A

2015-01-01

This study's objective was to determine seasonal and diurnal vs. nocturnal home range size, as well as predation for free-ranging farm cats at a livestock unit in Northwest Georgia. Seven adult cats were tracked with attached GPS units for up to two weeks for one spring and two summer seasons from May 2010 through August 2011. Three and five cats were tracked for up to two weeks during the fall and winter seasons, respectively. Feline scat was collected during this entire period. Cats were fed a commercial cat food daily. There was no seasonal effect (P > 0.05) on overall (95% KDE and 90% KDE) or core home range size (50% KDE). Male cats tended (P = 0.08) to have larger diurnal and nocturnal core home ranges (1.09 ha) compared to female cats (0.64 ha). Reproductively intact cats (n = 2) had larger (P ranges as compared to altered cats. Feline scat processing separated scat into prey parts, and of the 210 feline scats collected during the study, 75.24% contained hair. Of these 158 scat samples, 86 contained non-cat hair and 72 contained only cat hair. Other prey components included fragments of bone in 21.43% of scat and teeth in 12.86% of scat. Teeth were used to identify mammalian prey hunted by these cats, of which the Hispid cotton rat (Sigmodon hispidus) was the primary rodent. Other targeted mammals were Peromyscus sp., Sylvilagus sp. and Microtus sp. Invertebrates and birds were less important as prey, but all mammalian prey identified in this study consisted of native animals. While the free-ranging farm cats in this study did not adjust their home range seasonally, sex and reproductive status did increase diurnal and nocturnal home range size. Ultimately, larger home ranges of free-ranging cats could negatively impact native wildlife.

Time-Lapse Monitoring of DNA Damage Colocalized With Particle Tracks in Single Living Cells

Energy Technology Data Exchange (ETDEWEB)

McFadden, Conor H. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hallacy, Timothy M. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Physics and Astronomy, Rice University, Houston, Texas (United States); Flint, David B. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas (United States); Granville, Dal A. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada); Asaithamby, Aroumougame [Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Centre, Dallas, Texas (United States); Sahoo, Narayan [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Akselrod, Mark S. [Crystal Growth Division, Landauer, Inc, Stillwater, Oklahoma (United States); Sawakuchi, Gabriel O., E-mail: gsawakuchi@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas (United States)

2016-09-01

Purpose: Understanding the DNA damage and repair induced by hadron therapy (HT) beams is crucial for developing novel strategies to maximize the use of HT beams to treat cancer patients. However, spatiotemporal studies of DNA damage and repair for beam energies relevant to HT have been challenging. We report a technique that enables spatiotemporal measurement of radiation-induced damage in live cells and colocalization of this damage with charged particle tracks over a broad range of clinically relevant beam energies. The technique uses novel fluorescence nuclear track detectors with fluorescence confocal laser scanning microscopy in the beam line to visualize particle track traversals within the subcellular compartments of live cells within seconds after injury. Methods and Materials: We designed and built a portable fluorescence confocal laser scanning microscope for use in the beam path, coated fluorescence nuclear track detectors with fluorescent-tagged live cells (HT1080 expressing enhanced green fluorescent protein tagged to XRCC1, a single-strand break repair protein), placed the entire assembly into a proton therapy beam line, and irradiated the cells with a fluence of ∼1 × 10{sup 6} protons/cm{sup 2}. Results: We successfully obtained confocal images of proton tracks and foci of DNA single-strand breaks immediately after irradiation. Conclusions: This technique represents an innovative method for analyzing biological responses in any HT beam line at energies and dose rates relevant to therapy. It allows precise determination of the number of tracks traversing a subcellular compartment and monitoring the cellular damage therein, and has the potential to measure the linear energy transfer of each track from therapeutic beams.

Future changes in extratropical storm tracks and baroclinicity under climate change

International Nuclear Information System (INIS)

Lehmann, Jascha; Coumou, Dim; Frieler, Katja; Eliseev, Alexey V; Levermann, Anders

2014-01-01

The weather in Eurasia, Australia, and North and South America is largely controlled by the strength and position of extratropical storm tracks. Future climate change will likely affect these storm tracks and the associated transport of energy, momentum, and water vapour. Many recent studies have analyzed how storm tracks will change under climate change, and how these changes are related to atmospheric dynamics. However, there are still discrepancies between different studies on how storm tracks will change under future climate scenarios. Here, we show that under global warming the CMIP5 ensemble of coupled climate models projects only little relative changes in vertically averaged mid-latitude mean storm track activity during the northern winter, but agree in projecting a substantial decrease during summer. Seasonal changes in the Southern Hemisphere show the opposite behaviour, with an intensification in winter and no change during summer. These distinct seasonal changes in northern summer and southern winter storm tracks lead to an amplified seasonal cycle in a future climate. Similar changes are seen in the mid-latitude mean Eady growth rate maximum, a measure that combines changes in vertical shear and static stability based on baroclinic instability theory. Regression analysis between changes in the storm tracks and changes in the maximum Eady growth rate reveal that most models agree in a positive association between the two quantities over mid-latitude regions. (letter)

FTK status and track triggers in ATLAS at HL-LHC

CERN Document Server

ATLAS Collaboration; The ATLAS collaboration

2016-01-01

The expected instantaneous luminosities delivered by the Large Hadron Collider will place continually increasing burdens on the trigger systems of the ATLAS detector. The use of tracking information is key to maintaining a manageable trigger rate while keeping a high efficiency. At the same time, however, track finding is one of the more resource-intensive tasks in the software-based processing farms of the high level trigger system. To support the trigger, ATLAS is building and currently installing the Fast TracK Finder (FTK), a hardware-based system that uses massively parallel pattern recognition in Associative Memory to reconstruct tracks above transverse momenta of 1 GeV across the entire detector at 100 kHz with a latency of ~100 microseconds. In the first-stage of track finding, FTK compares hits in ATLAS silicon detectors against ~1 billion pre-computed track pattern candidates. Track parameters for these candidates, including goodness-of-fit tests, are calculated in FPGAs using a linear approximation...

Track Reconstruction in the ATLAS Experiment The Deterministic Annealing Filter

CERN Document Server

Fleischmann, S

2006-01-01

The reconstruction of the trajectories of charged particles is essential for experiments at the LHC. The experiments contain precise tracking systems structured in layers around the collision point which measure the positions where particle trajectories intersect those layers. The physics analysis on the other hand mainly needs the momentum and direction of the particle at the estimated creation or reaction point. It is therefore needed to determine these parameters from the initial measurements. At the LHC one has to deal with high backgrounds while even small deficits or artifacts can reduce the signal or may produce additional background after event selection. The track reconstruction does not only contain the estimation of the track parameters, but also a pattern recognition deciding which measurements belong to a track and how many particle tracks can be found. Track reconstruction at the ATLAS experiment suffers from the high event rate at the LHC resulting in a high occupancy of the tracking devices. A...

A new three-dimensional track fit with multiple scattering

International Nuclear Information System (INIS)

Berger, Niklaus; Kozlinskiy, Alexandr; Kiehn, Moritz; Schöning, André

2017-01-01

Modern semiconductor detectors allow for charged particle tracking with ever increasing position resolution. Due to the reduction of the spatial hit uncertainties, multiple Coulomb scattering in the detector layers becomes the dominant source for tracking uncertainties. In this case long distance effects can be ignored for the momentum measurement, and the track fit can consequently be formulated as a sum of independent fits to hit triplets. In this paper we present an analytical solution for a three-dimensional triplet(s) fit in a homogeneous magnetic field based on a multiple scattering model. Track fitting of hit triplets is performed using a linearization ansatz. The momentum resolution is discussed for a typical spectrometer setup. Furthermore the track fit is compared with other track fits for two different pixel detector geometries, namely the Mu3e experiment at PSI and a typical high-energy collider experiment. For a large momentum range the triplets fit provides a significantly better performance than a single helix fit. The triplets fit is fast and can easily be parallelized, which makes it ideal for the implementation on parallel computing architectures.

A new three-dimensional track fit with multiple scattering

Energy Technology Data Exchange (ETDEWEB)

Berger, Niklaus; Kozlinskiy, Alexandr [Physikalisches Institut, Heidelberg University, Heidelberg (Germany); Institut für Kernphysik and PRISMA cluster of excellence, Mainz University, Mainz (Germany); Kiehn, Moritz; Schöning, André [Physikalisches Institut, Heidelberg University, Heidelberg (Germany)

2017-02-01

Modern semiconductor detectors allow for charged particle tracking with ever increasing position resolution. Due to the reduction of the spatial hit uncertainties, multiple Coulomb scattering in the detector layers becomes the dominant source for tracking uncertainties. In this case long distance effects can be ignored for the momentum measurement, and the track fit can consequently be formulated as a sum of independent fits to hit triplets. In this paper we present an analytical solution for a three-dimensional triplet(s) fit in a homogeneous magnetic field based on a multiple scattering model. Track fitting of hit triplets is performed using a linearization ansatz. The momentum resolution is discussed for a typical spectrometer setup. Furthermore the track fit is compared with other track fits for two different pixel detector geometries, namely the Mu3e experiment at PSI and a typical high-energy collider experiment. For a large momentum range the triplets fit provides a significantly better performance than a single helix fit. The triplets fit is fast and can easily be parallelized, which makes it ideal for the implementation on parallel computing architectures.

Ionization yield from electron tracks in liquid xenon

International Nuclear Information System (INIS)

Voronova, T.Ya.; Kipsanov, M.A.; Kruglov, A.A.; Obodovskij, I.M.; Pokachalov, S.G.; Shilov, V.A.; Khristich, E.B.

1989-01-01

Methods for calculating coefficients K β , characterizing ionization yield from electron track in liquid xenon are considered. K β calculation is conducted on the base of experimental data on K parameter characterizing ionization yield from a certain combination of photo-, Compton-and Auger electron tracks. K parameter measurements are conducted in liquid xenon at 170 K temperature within 10-30 keV gamma- and X radiation energy ranges. Calculated dependence of K β and K coefficients on the energy in a wide (5-500 keV) range is presented. K β values obtained can be applied for calculating the energy resolution of a gamma-spectrometer and linearity of its calibration characteristics if the electric field intensity in the spectrometer does not exceed some kV/cm

Influence of tracks densities in solid state nuclear track detectors

International Nuclear Information System (INIS)

Guedes O, S.; Hadler N.; Lunes, P.; Saenz T, C.

1996-01-01

When Solid State Nuclear Track Detectors (SSNTD) is employed to measure nuclear tracks produced mainly by fission fragments and alpha particles, it is considered that the tracks observation work is performed under an efficiency, ε 0 , which is independent of the track density (number of tracks/area unit). There are not published results or experimental data supporting such an assumption. In this work the dependence of ε 0 with track density is studied basing on experimental data. To perform this, pieces of CR-39 cut from a sole 'mother sheet' were coupled to thin uranium films for different exposition times and the resulting ratios between track density and exposition time were compared. Our results indicate that ε 0 is constant for track densities between 10 3 and 10 5 cm -2 . At our etching conditions track overlapping makes impossible the counting for densities around 1.7 x 10 5 cm -2 . For track densities less than 10 3 cm -2 , ε 0 , was not observed to be constant. (authors). 4 refs., 2 figs

How to track protists in three dimensions

Science.gov (United States)

Drescher, Knut; Leptos, Kyriacos C.; Goldstein, Raymond E.

2009-01-01

We present an apparatus optimized for tracking swimming micro-organisms in the size range of 10-1000 μm, in three dimensions (3Ds), far from surfaces, and with negligible background convective fluid motion. Charge coupled device cameras attached to two long working distance microscopes synchronously image the sample from two perpendicular directions, with narrow band dark-field or bright-field illumination chosen to avoid triggering a phototactic response. The images from the two cameras can be combined to yield 3D tracks of the organism. Using additional, highly directional broad-spectrum illumination with millisecond timing control the phototactic trajectories in 3D of organisms ranging from Chlamydomonas to Volvox can be studied in detail. Surface-mediated hydrodynamic interactions can also be investigated without convective interference. Minimal modifications to the apparatus allow for studies of chemotaxis and other taxes.

Autonomous Target Ranging Techniques

DEFF Research Database (Denmark)

Jørgensen, Peter Siegbjørn; Jørgensen, John Leif; Denver, Troelz

2003-01-01

of this telescope, a fast determination of the range to and the motion of the detected targets are important. This is needed in order to prepare the future observation strategy for each target, i.e. when is the closest approach where imaging will be optimal. In order to quickly obtain such a determination two...... ranging strategies are presented. One is an improved laser ranger with an effective range with non-cooperative targets of at least 10,000 km, demonstrated in ground tests. The accuracy of the laser ranging will be approximately 1 m. The laser ranger may furthermore be used for trajectory determination...... of nano-gravity probes, which will perform direct mass measurements of selected targets. The other is triangulation from two spacecraft. For this method it is important to distinguish between detection and tracking range, which will be different for Bering since different instruments are used...

Clinical Validation of the Glenoid Track Concept in Anterior Glenohumeral Instability.

Science.gov (United States)

Shaha, James S; Cook, Jay B; Rowles, Douglas J; Bottoni, Craig R; Shaha, Steven H; Tokish, John M

2016-11-16

Glenoid and humeral bone loss are well-described risk factors for failure of arthroscopic shoulder stabilization. Recently, consideration of the interactions of these types of bone loss (bipolar bone loss) has been used to determine if a lesion is "on-track" or "off-track." The purpose of this study was to study the relationship of the glenoid track to the outcomes of arthroscopic Bankart reconstructions. Over a 2-year period, 57 shoulders that were treated with an isolated, primary arthroscopic Bankart reconstruction performed at a single facility were included in this study. The mean patient age was 25.5 years (range, 20 to 42 years) at the time of the surgical procedure, and the mean follow-up was 48.3 months (range, 23 to 58 months). Preoperative magnetic resonance imaging was used to determine glenoid bone loss and Hill-Sachs lesion size and location and to measure the glenoid track to classify the shoulders as on-track or off-track. Outcomes were assessed according to shoulder stability on examination and subjective outcome. There were 10 recurrences (18%). Of the 49 on-track patients, 4 (8%) had treatment that failed compared with 6 (75%) of 8 off-track patients (p = 0.0001). Six (60%) of 10 patients with recurrence of instability were off-track compared with 2 (4%) of 47 patients in the stable group (p = 0.0001). The positive predictive value of an off-track measurement was 75% compared with 44% for the predictive value of glenoid bone loss of >20%. The application of the glenoid track concept to our cohort was superior to using glenoid bone loss alone with regard to predicting postoperative stability. This method of assessment is encouraged as a routine part of the preoperative evaluation of all patients under consideration for arthroscopic anterior stabilization. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.

Automatic multimodal real-time tracking for image plane alignment in interventional Magnetic Resonance Imaging

International Nuclear Information System (INIS)

Neumann, Markus

2014-01-01

Interventional magnetic resonance imaging (MRI) aims at performing minimally invasive percutaneous interventions, such as tumor ablations and biopsies, under MRI guidance. During such interventions, the acquired MR image planes are typically aligned to the surgical instrument (needle) axis and to surrounding anatomical structures of interest in order to efficiently monitor the advancement in real-time of the instrument inside the patient's body. Object tracking inside the MRI is expected to facilitate and accelerate MR-guided interventions by allowing to automatically align the image planes to the surgical instrument. In this PhD thesis, an image-based work-flow is proposed and refined for automatic image plane alignment. An automatic tracking work-flow was developed, performing detection and tracking of a passive marker directly in clinical real-time images. This tracking work-flow is designed for fully automated image plane alignment, with minimization of tracking-dedicated time. Its main drawback is its inherent dependence on the slow clinical MRI update rate. First, the addition of motion estimation and prediction with a Kalman filter was investigated and improved the work-flow tracking performance. Second, a complementary optical sensor was used for multi-sensor tracking in order to decouple the tracking update rate from the MR image acquisition rate. Performance of the work-flow was evaluated with both computer simulations and experiments using an MR compatible test bed. Results show a high robustness of the multi-sensor tracking approach for dynamic image plane alignment, due to the combination of the individual strengths of each sensor. (author)

NM-Scale Anatomy of an Entire Stardust Carrot Track

Science.gov (United States)

Nakamura-Messenger, K.; Keller, L. P.; Clemett, S. J.; Messenger, S.

2009-01-01

Comet Wild-2 samples collected by NASA s Stardust mission are extremely complex, heterogeneous, and have experienced wide ranges of alteration during the capture process. There are two major types of track morphologies: "carrot" and "bulbous," that reflect different structural/compositional properties of the impactors. Carrot type tracks are typically produced by compact or single mineral grains which survive essentially intact as a single large terminal particle. Bulbous tracks are likely produced by fine-grained or organic-rich impactors [1]. Owing to their challenging nature and especially high value of Stardust samples, we have invested considerable effort in developing both sample preparation and analytical techniques tailored for Stardust sample analyses. Our report focuses on our systematic disassembly and coordinated analysis of Stardust carrot track #112 from the mm to nm-scale.

Cooling rate and size effects on the medium-range structure of multicomponent oxide glasses simulated by molecular dynamics

Energy Technology Data Exchange (ETDEWEB)

Tilocca, Antonio [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

2013-09-21

A set of molecular dynamics simulations were performed to investigate the effect of cooling rate and system size on the medium-range structure of melt-derived multicomponent silicate glasses, represented by the quaternary 45S5 Bioglass composition. Given the significant impact of the glass degradation on applications of these materials in biomedicine and nuclear waste disposal, bulk structural features which directly affect the glass dissolution process are of particular interest. Connectivity of the silicate matrix, ion clustering and nanosegregation, distribution of ring and chain structural patterns represent critical features in this context, which can be directly extracted from the models. A key issue is represented by the effect of the computational approach on the corresponding glass models, especially in light of recent indications questioning the suitability of conventional MD approaches (that is, involving melt-and-quench of systems containing ∼10{sup 3} atoms at cooling rates of 5-10 K/ps) when applied to model these glasses. The analysis presented here compares MD models obtained with conventional and nonconventional cooling rates and system sizes, highlighting the trend and range of convergence of specific structural features in the medium range. The present results show that time-consuming computational approaches involving much lower cooling rates and/or significantly larger system sizes are in most cases not necessary in order to obtain a reliable description of the medium-range structure of multicomponent glasses. We identify the convergence range for specific properties and use them to discuss models of several glass compositions for which a possible influence of cooling-rate or size effects had been previously hypothesized. The trends highlighted here represent an important reference to obtain reliable models of multicomponent glasses and extract converged medium-range structural features which affect the glass degradation and thus their

Cooling rate and size effects on the medium-range structure of multicomponent oxide glasses simulated by molecular dynamics

International Nuclear Information System (INIS)

Tilocca, Antonio

2013-01-01

A set of molecular dynamics simulations were performed to investigate the effect of cooling rate and system size on the medium-range structure of melt-derived multicomponent silicate glasses, represented by the quaternary 45S5 Bioglass composition. Given the significant impact of the glass degradation on applications of these materials in biomedicine and nuclear waste disposal, bulk structural features which directly affect the glass dissolution process are of particular interest. Connectivity of the silicate matrix, ion clustering and nanosegregation, distribution of ring and chain structural patterns represent critical features in this context, which can be directly extracted from the models. A key issue is represented by the effect of the computational approach on the corresponding glass models, especially in light of recent indications questioning the suitability of conventional MD approaches (that is, involving melt-and-quench of systems containing ∼10 3 atoms at cooling rates of 5-10 K/ps) when applied to model these glasses. The analysis presented here compares MD models obtained with conventional and nonconventional cooling rates and system sizes, highlighting the trend and range of convergence of specific structural features in the medium range. The present results show that time-consuming computational approaches involving much lower cooling rates and/or significantly larger system sizes are in most cases not necessary in order to obtain a reliable description of the medium-range structure of multicomponent glasses. We identify the convergence range for specific properties and use them to discuss models of several glass compositions for which a possible influence of cooling-rate or size effects had been previously hypothesized. The trends highlighted here represent an important reference to obtain reliable models of multicomponent glasses and extract converged medium-range structural features which affect the glass degradation and thus their application

The relationship between fission track length and track density in apatite

International Nuclear Information System (INIS)

Laslett, G.M.; Gleadow, A.J.W.; Duddy, I.R.

1984-01-01

Fission track dating is based upon an age equation derived from a random line segment model for fission tracks. This equation contains the implicit assumption of a proportional relationship between the true mean length of fission tracks and their track density in an isotropic medium. Previous experimental investigation of this relationship for both spontaneous and induced tracks in apatite during progressive annealment model in an obvious fashion. Corrected equations relating track length and density for apatite, an anisotropic mineral, show that the proportionality in this case is between track density and a length factor which is a generalization of the mean track length combining the actual length and crystallographic orientation of the track. This relationship has been experimentally confirmed for induced tracks in Durango apatite, taking into account bias in sampling of the track lengths, and the effect of the bulk etching velocity. (author)

Tracking and recognition face in videos with incremental local sparse representation model

Science.gov (United States)

Wang, Chao; Wang, Yunhong; Zhang, Zhaoxiang

2013-10-01

This paper addresses the problem of tracking and recognizing faces via incremental local sparse representation. First a robust face tracking algorithm is proposed via employing local sparse appearance and covariance pooling method. In the following face recognition stage, with the employment of a novel template update strategy, which combines incremental subspace learning, our recognition algorithm adapts the template to appearance changes and reduces the influence of occlusion and illumination variation. This leads to a robust video-based face tracking and recognition with desirable performance. In the experiments, we test the quality of face recognition in real-world noisy videos on YouTube database, which includes 47 celebrities. Our proposed method produces a high face recognition rate at 95% of all videos. The proposed face tracking and recognition algorithms are also tested on a set of noisy videos under heavy occlusion and illumination variation. The tracking results on challenging benchmark videos demonstrate that the proposed tracking algorithm performs favorably against several state-of-the-art methods. In the case of the challenging dataset in which faces undergo occlusion and illumination variation, and tracking and recognition experiments under significant pose variation on the University of California, San Diego (Honda/UCSD) database, our proposed method also consistently demonstrates a high recognition rate.

Symplectic Tracking of Multi-Isotopic Heavy-Ion Beams in SixTrack

CERN Document Server

Hermes, Pascal; De Maria, Riccardo

2016-01-01

The software SixTrack provides symplectic proton tracking over a large number of turns. The code is used for the tracking of beam halo particles and the simulation of their interaction with the collimators to study the efficiency of the LHC collimation system. Tracking simulations for heavy-ion beams require taking into account the mass to charge ratio of each particle because heavy ions can be subject to fragmentation at their passage through the collimators. In this paper we present the derivation of a Hamiltonian for multi-isotopic heavy-ion beams and symplectic tracking maps derived from it. The resulting tracking maps were implemented in the tracking software SixTrack. With this modification, SixTrack can be used to natively track heavy-ion beams of multiple isotopes through a magnetic accelerator lattice.

Bulk etching characteristics of CR-39 track detectors in hydroxide solutions

International Nuclear Information System (INIS)

Fonseca, E.S. da; Knoefel, T.M.J.; Tavares, O.A.P.

1983-01-01

A systematic study of the bulk etch rate of CR-39 track detectors in KOH and NaOH aqueous solutions is presented. A number of unirradiated and non-thermally treated CR-39 samples were chemically attacked in KOH and NaOH solutions of concentration and temperature in the range 2-10 N and 50-90 0 C, respectively. From measurements of the thickness of layers removed as a function of the etching time, the bulk etch rate υ β and the induction time T ο for surface removal were obtained for each etching condition. For both NaOH and KOH solution the activation energy of the process was derived as E = 0.76 ± 0.05 eV. It was observed that the induction time decreases both with increasing normality and temperature of the solution. (author) [pt

The ALICE Inner Tracking System Upgrade

CERN Document Server

Siddhanta, Sabyasachi

2015-01-01

The long term plan of ALICE (A Large Ion Collider Experiment) at the CERN Large Hadron Collider (LHC) is a detailed investigation and characterisation of the Quark-Gluon Plasma (QGP). ALICE has devised a comprehensive upgrade strategy to enhance its physics capabilities and to exploit the LHC running conditions after the second long shutdown of the LHC scheduled in 2019-20. The upgraded ALICE will focus on high precision measurements of rare probes over a wide range of momenta, which will significantly improve the performance with respect to the present experimental set up. The upgrade strategy is based on the fact that after LS2 LHC will progressively increase its luminosity with Pb beams eventually reaching an interaction rate of about 50 kHz. To exploit the new LHC capabilities, several existing detectors will undergo a substantial upgrade and new detectors will be added. Within this upgrade strategy, the Inner Tracking System (ITS) upgrade forms an important cornerstone, providing precise measurements for...

Towards an IMU Evaluation Framework for Human Body Tracking.

Science.gov (United States)

Venek, Verena; Kremser, Wolfgang; Schneider, Cornelia

2018-01-01

Existing full-body tracking systems, which use Inertial Measurement Units (IMUs) as sensing unit, require expert knowledge for setup and data collection. Thus, the daily application for human body tracking is difficult. In particular, in the field of active and assisted living (AAL), tracking human movements would enable novel insights not only into the quantity but also into the quality of human movement, for example by monitoring functional training. While the current market offers a wide range of products with vastly different properties, literature lacks guidelines for choosing IMUs for body tracking applications. Therefore, this paper introduces developments towards an IMU evaluation framework for human body tracking which compares IMUs against five requirement areas that consider device features and data quality. The data quality is assessed by conducting a static and a dynamic error analysis. In a first application to four IMUs of different component consumption, the IMU evaluation framework convinced as promising tool for IMU selection.

Joint Conditional Random Field Filter for Multi-Object Tracking

Directory of Open Access Journals (Sweden)

Luo Ronghua

2011-03-01

Full Text Available Object tracking can improve the performance of mobile robot especially in populated dynamic environments. A novel joint conditional random field Filter (JCRFF based on conditional random field with hierarchical structure is proposed for multi-object tracking by abstracting the data associations between objects and measurements to be a sequence of labels. Since the conditional random field makes no assumptions about the dependency structure between the observations and it allows non-local dependencies between the state and the observations, the proposed method can not only fuse multiple cues including shape information and motion information to improve the stability of tracking, but also integrate moving object detection and object tracking quite well. At the same time, implementation of multi-object tracking based on JCRFF with measurements from the laser range finder on a mobile robot is studied. Experimental results with the mobile robot developed in our lab show that the proposed method has higher precision and better stability than joint probabilities data association filter (JPDAF.

Development and Application of the Stereo Vision Tracking System with Virtual Reality

Directory of Open Access Journals (Sweden)

Chia-Sui Wang

2015-01-01

Full Text Available A virtual reality (VR driver tracking verification system is created, of which the application to stereo image tracking and positioning accuracy is researched in depth. In the research, the feature that the stereo vision system has image depth is utilized to improve the error rate of image tracking and image measurement. In a VR scenario, the function collecting behavioral data of driver was tested. By means of VR, racing operation is simulated and environmental (special weathers such as raining and snowing and artificial (such as sudden crossing road by pedestrians, appearing of vehicles from dead angles, roadblock variables are added as the base for system implementation. In addition, the implementation is performed with human factors engineered according to sudden conditions that may happen easily in driving. From experimental results, it proves that the stereo vision system created by the research has an image depth recognition error rate within 0.011%. The image tracking error rate may be smaller than 2.5%. In the research, the image recognition function of stereo vision is utilized to accomplish the data collection of driver tracking detection. In addition, the environmental conditions of different simulated real scenarios may also be created through VR.

A CONTENT ANALYSIS OF WIRED MAGAZINE IN TERMS OF SELF-TRACKING DEVICES

OpenAIRE

AKYAMAN, Serefraz; AYAS ÖNOL, Tuğba

2018-01-01

In the digital era that we live in now it is possible to gather biological and biographical data of an individual by wearable digital health and activity-tracking devices. The phenomenon is known as self-tracking and it intends to expand individual’s self-knowledge and as a result to improve both the physical and psychological health. By self-tracking applications that digital health and activity-tracking devices provide now we can measure diverse biodata from heart rate, body fat percentage ...

Spacecraft Attitude Tracking and Maneuver Using Combined Magnetic Actuators

Science.gov (United States)

Zhou, Zhiqiang

2012-01-01

A paper describes attitude-control algorithms using the combination of magnetic actuators with reaction wheel assemblies (RWAs) or other types of actuators such as thrusters. The combination of magnetic actuators with one or two RWAs aligned with different body axis expands the two-dimensional control torque to three-dimensional. The algorithms can guarantee the spacecraft attitude and rates to track the commanded attitude precisely. A design example is presented for nadir-pointing, pitch, and yaw maneuvers. The results show that precise attitude tracking can be reached and the attitude- control accuracy is comparable with RWA-based attitude control. When there are only one or two workable RWAs due to RWA failures, the attitude-control system can switch to the control algorithms for the combined magnetic actuators with the RWAs without going to the safe mode, and the control accuracy can be maintained. The attitude-control algorithms of the combined actuators are derived, which can guarantee the spacecraft attitude and rates to track the commanded values precisely. Results show that precise attitude tracking can be reached, and the attitude-control accuracy is comparable with 3-axis wheel control.

Free-Ranging Farm Cats: Home Range Size and Predation on a Livestock Unit In Northwest Georgia

Science.gov (United States)

Kitts-Morgan, Susanna E.; Caires, Kyle C.; Bohannon, Lisa A.; Parsons, Elizabeth I.; Hilburn, Katharine A.

2015-01-01

This study’s objective was to determine seasonal and diurnal vs. nocturnal home range size, as well as predation for free-ranging farm cats at a livestock unit in Northwest Georgia. Seven adult cats were tracked with attached GPS units for up to two weeks for one spring and two summer seasons from May 2010 through August 2011. Three and five cats were tracked for up to two weeks during the fall and winter seasons, respectively. Feline scat was collected during this entire period. Cats were fed a commercial cat food daily. There was no seasonal effect (P > 0.05) on overall (95% KDE and 90% KDE) or core home range size (50% KDE). Male cats tended (P = 0.08) to have larger diurnal and nocturnal core home ranges (1.09 ha) compared to female cats (0.64 ha). Reproductively intact cats (n = 2) had larger (P cats. Feline scat processing separated scat into prey parts, and of the 210 feline scats collected during the study, 75.24% contained hair. Of these 158 scat samples, 86 contained non-cat hair and 72 contained only cat hair. Other prey components included fragments of bone in 21.43% of scat and teeth in 12.86% of scat. Teeth were used to identify mammalian prey hunted by these cats, of which the Hispid cotton rat (Sigmodon hispidus) was the primary rodent. Other targeted mammals were Peromyscus sp., Sylvilagus sp. and Microtus sp. Invertebrates and birds were less important as prey, but all mammalian prey identified in this study consisted of native animals. While the free-ranging farm cats in this study did not adjust their home range seasonally, sex and reproductive status did increase diurnal and nocturnal home range size. Ultimately, larger home ranges of free-ranging cats could negatively impact native wildlife. PMID:25894078

Preamplifier development for high count-rate, large dynamic range readout of inorganic scintillators

Energy Technology Data Exchange (ETDEWEB)

Keshelashvili, Irakli; Erni, Werner; Steinacher, Michael; Krusche, Bernd; Collaboration: PANDA-Collaboration

2013-07-01

Electromagnetic calorimeter are central component of many experiments in nuclear and particle physics. Modern ''trigger less'' detectors run with very high count-rates, require good time and energy resolution, and large dynamic range. In addition photosensors and preamplifiers must work in hostile environments (magnetic fields). Due to later constraints mainly Avalanche Photo Diodes (APD's), Vacuum Photo Triodes (VPT's), and Vacuum Photo Tetrodes (VPTT's) are used. A disadvantage is their low gain which together with other requirements is a challenge for the preamplifier design. Our group has developed special Low Noise / Low Power (LNP) preamplifier for this purpose. They will be used to equip PANDA EMC forward end-cap (dynamic range 15'000, rate 1MHz), where the PWO II crystals and preamplifier have to run in an environment cooled down to -25{sup o}C. Further application is the upgrade of the Crystal Barrel detector at the Bonn ELSA accelerator with APD readout for which special temperature comparison of the APD gain and good time resolution is necessary. Development and all test procedures after the mass production done by our group during past several years in Basel University will be reported.

Use of a track and vertex processor in a fixed-target charm experiment

International Nuclear Information System (INIS)

Schub, M.H.; Carey, T.A.; Hsiung, Y.B.; Kaplan, D.M.; Lee, C.; Miller, G.; Sa, J.; Teng, P.K.

1996-01-01

We have constructed and operated a high-speed parallel-pipelined track and vertex processor and used it to trigger data acquisition in a high-rate charm and beauty experiment at Fermilab. The processor uses information from hodoscopes and wire chambers to reconstruct tracks in the bend view of a magnetic spectrometer, and uses these tracks to find the corresponding tracks in a set of silicon-strip detectors. The processor then forms vertices and triggers the experiment if at least one vertex is downstream of the target. Under typical charm running conditions, with an interaction rate of ∼5 MHz, the processor rejects 80-90% of lower-level triggers while maintaining efficiency of ∼70% for two-prong D-meson decays. (orig.)

On the use of particle filters for electromagnetic tracking in high dose rate brachytherapy

Science.gov (United States)

Götz, Th I.; Lahmer, G.; Brandt, T.; Kallis, K.; Strnad, V.; Bert, Ch; Hensel, B.; Tomé, A. M.; Lang, E. W.

2017-10-01

Modern radiotherapy of female breast cancers often employs high dose rate brachytherapy, where a radioactive source is moved inside catheters, implanted in the female breast, according to a prescribed treatment plan. Source localization relative to the patient’s anatomy is determined with solenoid sensors whose spatial positions are measured with an electromagnetic tracking system. Precise sensor dwell position determination is of utmost importance to assure irradiation of the cancerous tissue according to the treatment plan. We present a hybrid data analysis system which combines multi-dimensional scaling with particle filters to precisely determine sensor dwell positions in the catheters during subsequent radiation treatment sessions. Both techniques are complemented with empirical mode decomposition for the removal of superimposed breathing artifacts. We show that the hybrid model robustly and reliably determines the spatial positions of all catheters used during the treatment and precisely determines any deviations of actual sensor dwell positions from the treatment plan. The hybrid system only relies on sensor positions measured with an EMT system and relates them to the spatial positions of the implanted catheters as initially determined with a computed x-ray tomography.

S-band multiple-access interference study for advanced tracking and data relay satellite systems

Science.gov (United States)

Peng, Wei-Chung; Yang, Chau-Chin

1990-01-01

The results of a study on the effect of mutual interference among S-band multiple access (SMA) system users of advanced tracking and data relay satellite system (ATDRSS) are presented. In the ATDRSS era, the SMA system is required to support data rates ranging from 10 kb/s to 3 Mb/s. The system will consist of four advanced tracking and data relay satellites (ATDRS) each supporting up to five telemetry links. All users have 10 MHz bandwidth with their carrier frequency equal to 2.2875 GHz. A hybrid SDMA/CDMA scheme is used to mitigate the effect of the interference among system users. SMA system interference probability is evaluated with CLASS software. User link margin degradation due to mutual interference between two users is evaluated. System interference probability is evaluated for the projected 1996 mission model, a reference mission model, and a modified reference mission model.

Impact of Physician Education and a Dedicated Inferior Vena Cava Filter Tracking System on Inferior Vena Cava Filter Use and Retrieval Rates Across a Large US Health Care Region.

Science.gov (United States)

Wang, Stephen L; Cha, Hsien-Hwa A; Lin, James R; Francis, Bolanos; Elizabeth, Wakley; Martin, Porras; Rajan, Sudhir

2016-05-01

To evaluate the effects of physician familiarity with current evidence and guidelines on inferior vena cava (IVC) filter use and the availability of IVC filter tracking infrastructure on retrieval rates. Fourteen continuing medical education-approved in-hospital grand rounds covering evidence-based review of the literature on IVC filter efficacy, patient-centered outcomes, guidelines for IVC filter indications, and complications were performed across a large United States (US) health care region serving more than 3.5 million members. A computer-based IVC filter tracking system was deployed simultaneously. IVC filter use, rates of attempted retrieval, and fulfillment of guidelines for IVC filter indications were retrospectively evaluated at each facility for 12 months before intervention (n = 427) and for 12 months after intervention (n = 347). After education, IVC filter use decreased 18.7%, with a member enrollment-adjusted decrease of 22.2%, despite an increasing IVC filter use trend for 4 years. Reduction in IVC filter use at each facility strongly correlated with physician attendance at grand rounds (r = -0.69; P = .007). Rates of attempted retrieval increased from 38.9% to 54.0% (P = .0006), with similar rates of successful retrieval (82.3% before education and 85.8% after education on first attempt). Improvement in IVC filter retrieval attempts correlated with physician attendance at grand rounds (r = 0.51; P = .051). IVC filter dwell times at first retrieval attempt were similar (10.2 wk before and 10.8 wk after). Physician education dramatically reduced IVC filter use across a large US health care region, and represents a learning opportunity for physicians who request and place them. Education and a novel tracking system improved rates of retrieval for IVC filter devices. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

The ZEUS central tracking detector. Der zentrale Spuren-Detektor von ZEUS

Energy Technology Data Exchange (ETDEWEB)

Saxon, D H

1989-12-01

The Central Tracking Detector (CTD) of ZEUS covers a wide angular range, whilst the Forward Detector - comprising the Forward Tracking Detector (FTD) and electron identification by transition radiation - concentrates on the important forward cone. The RTD (Rear Tracking Detector) provides accurate angle measurement of the recoil electron and the vertex detector (VXD) aims to find particles from heavy flavour decay. To measure momentum accurately the CTD sits in a high magnetic field (B=1,8 T) within the ZEUS calorimeter. (orig./HSI).

A novel generic framework for track fitting in complex detector systems

International Nuclear Information System (INIS)

Hoeppner, C.; Neubert, S.; Ketzer, B.; Paul, S.

2010-01-01

This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices through the experiment are also implemented as interchangeable modules. Different track parameterizations and extrapolation routines can be used simultaneously for fitting of the same physical track. Representations of detector hits are the third modular ingredient to the framework. The hit dimensionality and orientation of planar tracking detectors are not restricted. Tracking information from detectors which do not measure the passage of particles in a fixed physical detector plane, e.g. drift chambers or TPCs, is used without any simplification. The concept is implemented in a light-weight C++ library called GENFIT, which is available as free software.

A novel generic framework for track fitting in complex detector systems

Energy Technology Data Exchange (ETDEWEB)

Hoeppner, C., E-mail: christian.hoeppner@cern.c [Technische Universitaet Muenchen, Physik Department, 85748 Garching (Germany); Neubert, S.; Ketzer, B.; Paul, S. [Technische Universitaet Muenchen, Physik Department, 85748 Garching (Germany)

2010-08-21

This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices through the experiment are also implemented as interchangeable modules. Different track parameterizations and extrapolation routines can be used simultaneously for fitting of the same physical track. Representations of detector hits are the third modular ingredient to the framework. The hit dimensionality and orientation of planar tracking detectors are not restricted. Tracking information from detectors which do not measure the passage of particles in a fixed physical detector plane, e.g. drift chambers or TPCs, is used without any simplification. The concept is implemented in a light-weight C++ library called GENFIT, which is available as free software.

Track Detection in Railway Sidings Based on MEMS Gyroscope Sensors

Science.gov (United States)

Broquetas, Antoni; Comerón, Adolf; Gelonch, Antoni; Fuertes, Josep M.; Castro, J. Antonio; Felip, Damià; López, Miguel A.; Pulido, José A.

2012-01-01

The paper presents a two-step technique for real-time track detection in single-track railway sidings using low-cost MEMS gyroscopes. The objective is to reliably know the path the train has taken in a switch, diverted or main road, immediately after the train head leaves the switch. The signal delivered by the gyroscope is first processed by an adaptive low-pass filter that rejects noise and converts the temporal turn rate data in degree/second units into spatial turn rate data in degree/meter. The conversion is based on the travelled distance taken from odometer data. The filter is implemented to achieve a speed-dependent cut-off frequency to maximize the signal-to-noise ratio. Although direct comparison of the filtered turn rate signal with a predetermined threshold is possible, the paper shows that better detection performance can be achieved by processing the turn rate signal with a filter matched to the rail switch curvature parameters. Implementation aspects of the track detector have been optimized for real-time operation. The detector has been tested with both simulated data and real data acquired in railway campaigns. PMID:23443376

PolarTrack: Optical Outside-In Device Tracking that Exploits Display Polarization

DEFF Research Database (Denmark)

Rädle, Roman; Jetter, Hans-Christian; Fischer, Jonathan

2018-01-01

PolarTrack is a novel camera-based approach to detecting and tracking mobile devices inside the capture volume. In PolarTrack, a polarization filter continuously rotates in front of an off-the-shelf color camera, which causes the displays of observed devices to periodically blink in the camera feed....... The periodic blinking results from the physical characteristics of current displays, which shine polarized light either through an LC overlay to produce images or through a polarizer to reduce light reflections on OLED displays. PolarTrack runs a simple detection algorithm on the camera feed to segment...... displays and track their locations and orientations, which makes PolarTrack particularly suitable as a tracking system for cross-device interaction with mobile devices. Our evaluation of PolarTrack's tracking quality and comparison with state-of-the-art camera-based multi-device tracking showed a better...

A self seeded first level track trigger for ATLAS

International Nuclear Information System (INIS)

Schöning, A

2012-01-01

For the planned high luminosity upgrade of the Large Hadron Collider, aiming to increase the instantaneous luminosity to 5 × 10 34 cm −2 s −1 , the implementation of a first level track trigger has been proposed. This trigger could be installed in the year ∼ 2021 along with the complete renewal of the ATLAS inner detector. The fast readout of the hit information from the Inner Detector is considered as the main challenge of such a track trigger. Different concepts for the implementation of a first level trigger are currently studied within the ATLAS collaboration. The so called 'Self Seeded' track trigger concept exploits fast frontend filtering algorithms based on cluster size reconstruction and fast vector tracking to select hits associated to high momentum tracks. Simulation studies have been performed and results on efficiencies, purities and trigger rates are presented for different layouts.

A study of CR-39 track response to charged particles from NOVA implosions

International Nuclear Information System (INIS)

Phillips, T.W.; Cable, M.D.; Hicks, D.G.; Li, C.K.; Petrasso, R.D.; Seguin, F.H.

1996-01-01

We have exposed CR-39 track recording material to a number of NOVA implosions. Radiation from the implosion passed through an array of ranging filters, which aided identification of the incident particles and their energies. The etching procedure was calibrated by including a piece of track exposed to DD protons from a small accelerator. For the same shots, we quantitatively compare the DD neutron yield with the DD proton yield determined from the track. In DT implosions, tracks produced by neutron interactions prevent observation of charged-particle tracks that are produced by the processes of knock-on, secondary or tertiary fusion

Computationally Efficient Automatic Coast Mode Target Tracking Based on Occlusion Awareness in Infrared Images.

Science.gov (United States)

Kim, Sohyun; Jang, Gwang-Il; Kim, Sungho; Kim, Junmo

2018-03-27

This paper proposes the automatic coast mode tracking of centroid trackers for infrared images to overcome the target occlusion status. The centroid tracking method, using only the brightness information of an image, is still widely used in infrared imaging tracking systems because it is difficult to extract meaningful features from infrared images. However, centroid trackers are likely to lose the track because they are highly vulnerable to screened status by the clutter or background. Coast mode, one of the tracking modes, maintains the servo slew rate with the tracking rate right before the loss of track. The proposed automatic coast mode tracking method makes decisions regarding entering coast mode by the prediction of target occlusion and tries to re-lock the target and resume the tracking after blind time. This algorithm comprises three steps. The first step is the prediction process of the occlusion by checking both matters which have target-likelihood brightness and which may screen the target despite different brightness. The second step is the process making inertial tracking commands to the servo. The last step is the process of re-locking a target based on the target modeling of histogram ratio. The effectiveness of the proposed algorithm is addressed by presenting experimental results based on computer simulation with various test imagery sequences compared to published tracking algorithms. The proposed algorithm is tested under a real environment with a naval electro-optical tracking system (EOTS) and airborne EO/IR system.

Computationally Efficient Automatic Coast Mode Target Tracking Based on Occlusion Awareness in Infrared Images

Directory of Open Access Journals (Sweden)

Sohyun Kim

2018-03-01

Full Text Available This paper proposes the automatic coast mode tracking of centroid trackers for infrared images to overcome the target occlusion status. The centroid tracking method, using only the brightness information of an image, is still widely used in infrared imaging tracking systems because it is difficult to extract meaningful features from infrared images. However, centroid trackers are likely to lose the track because they are highly vulnerable to screened status by the clutter or background. Coast mode, one of the tracking modes, maintains the servo slew rate with the tracking rate right before the loss of track. The proposed automatic coast mode tracking method makes decisions regarding entering coast mode by the prediction of target occlusion and tries to re-lock the target and resume the tracking after blind time. This algorithm comprises three steps. The first step is the prediction process of the occlusion by checking both matters which have target-likelihood brightness and which may screen the target despite different brightness. The second step is the process making inertial tracking commands to the servo. The last step is the process of re-locking a target based on the target modeling of histogram ratio. The effectiveness of the proposed algorithm is addressed by presenting experimental results based on computer simulation with various test imagery sequences compared to published tracking algorithms. The proposed algorithm is tested under a real environment with a naval electro-optical tracking system (EOTS and airborne EO/IR system.

Tracking and vertexing for B physics at hadron accelerators

International Nuclear Information System (INIS)

Johnson, R.; Purohit, M.; Weidemann, A.W.

1993-01-01

In this note, the authors report on some of the activities of the Tracking and Vertexing Working Group of this Workshop. Track and vertex finding is essential to exploit the high production rate of B-mesons at hadron accelerators, both for triggering and analysis. Here, they review the tracking and vertex-finding systems of some of the major existing and proposed collider and fixed-target experiments at existing and future hadron accelerators, with a view towards their usefulness for B-physics. The capabilities of both general-purpose detectors and those of dedicated B-physics experiments are considered

Track structure model of cell damage in space flight

Science.gov (United States)

Katz, Robert; Cucinotta, Francis A.; Wilson, John W.; Shinn, Judy L.; Ngo, Duc M.

1992-01-01

The phenomenological track-structure model of cell damage is discussed. A description of the application of the track-structure model with the NASA Langley transport code for laboratory and space radiation is given. Comparisons to experimental results for cell survival during exposure to monoenergetic, heavy-ion beams are made. The model is also applied to predict cell damage rates and relative biological effectiveness for deep-space exposures.

Hardware-based tracking at trigger level for ATLAS: The Fast Tracker (FTK) Project

CERN Document Server

Gramling, Johanna; The ATLAS collaboration

2015-01-01

Physics collisions at 13 TeV are expected at the LHC with an average of 40-50 proton-proton collisions per bunch crossing. Tracking at trigger level is an essential tool to control the rate in high-pileup conditions while maintaining a good efficiency for relevant physics processes. The Fast TracKer (FTK) is an integral part of the trigger upgrade for the ATLAS detector. For every event passing the Level 1 trigger (at a maximum rate of 100 kHz) the FTK receives data from the 80 million channels of the silicon detectors, providing tracking information to the High Level Trigger in order to ensure a selection robust against pile-up. The FTK performs a hardware-based track reconstruction, using associative memory (AM) that is based on the use of a custom chip, designed to perform pattern matching at very high speed. It finds track candidates at low resolution (roads) that seed a full-resolution track fitting done by FPGAs. Narrow roads permit a fast track fitting but need many patterns stored in the AM to ensure ...

The seam visual tracking method for large structures

Science.gov (United States)

Bi, Qilin; Jiang, Xiaomin; Liu, Xiaoguang; Cheng, Taobo; Zhu, Yulong

2017-10-01

In this paper, a compact and flexible weld visual tracking method is proposed. Firstly, there was the interference between the visual device and the work-piece to be welded when visual tracking height cannot change. a kind of weld vision system with compact structure and tracking height is researched. Secondly, according to analyze the relative spatial pose between the camera, the laser and the work-piece to be welded and study with the theory of relative geometric imaging, The mathematical model between image feature parameters and three-dimensional trajectory of the assembly gap to be welded is established. Thirdly, the visual imaging parameters of line structured light are optimized by experiment of the weld structure of the weld. Fourth, the interference that line structure light will be scatters at the bright area of metal and the area of surface scratches will be bright is exited in the imaging. These disturbances seriously affect the computational efficiency. The algorithm based on the human eye visual attention mechanism is used to extract the weld characteristics efficiently and stably. Finally, in the experiment, It is verified that the compact and flexible weld tracking method has the tracking accuracy of 0.5mm in the tracking of large structural parts. It is a wide range of industrial application prospects.

Solar Flare Track Exposure Ages in Regolith Particles: A Calibration for Transmission Electron Microscope Measurements

Science.gov (United States)

Berger, Eve L.; Keller, Lindsay P.

2015-01-01

Mineral grains in lunar and asteroidal regolith samples provide a unique record of their interaction with the space environment. Space weathering effects result from multiple processes including: exposure to the solar wind, which results in ion damage and implantation effects that are preserved in the rims of grains (typically the outermost 100 nm); cosmic ray and solar flare activity, which result in track formation; and impact processes that result in the accumulation of vapor-deposited elements, impact melts and adhering grains on particle surfaces. Determining the rate at which these effects accumulate in the grains during their space exposure is critical to studies of the surface evolution of airless bodies. Solar flare energetic particles (mainly Fe-group nuclei) have a penetration depth of a few millimeters and leave a trail of ionization damage in insulating materials that is readily observable by transmission electron microscope (TEM) imaging. The density of solar flare particle tracks is used to infer the length of time an object was at or near the regolith surface (i.e., its exposure age). Track measurements by TEM methods are routine, yet track production rate calibrations have only been determined using chemical etching techniques [e.g., 1, and references therein]. We used focused ion beam-scanning electron microscope (FIB-SEM) sample preparation techniques combined with TEM imaging to determine the track density/exposure age relations for lunar rock 64455. The 64455 sample was used earlier by [2] to determine a track production rate by chemical etching of tracks in anorthite. Here, we show that combined FIB/TEM techniques provide a more accurate determination of a track production rate and also allow us to extend the calibration to solar flare tracks in olivine.

On increasing the spectral efficiency and transmissivity in the data transmission channel on the spacecraft-ground tracking station line

Science.gov (United States)

Andrianov, M. N.; Kostenko, V. I.; Likhachev, S. F.

2018-01-01

The algorithms for achieving a practical increase in the rate of data transmission on the space-craft-ground tracking station line has been considered. This increase is achieved by applying spectral-effective modulation techniques, the technology of orthogonal frequency compression of signals using millimeterrange radio waves. The advantages and disadvantages of each of three algorithms have been revealed. A significant advantage of data transmission in the millimeter range has been indicated.

Tracking Mobile Robot in Indoor Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Liping Zhang

2014-01-01

Full Text Available This work addresses the problem of tracking mobile robots in indoor wireless sensor networks (WSNs. Our approach is based on a localization scheme with RSSI (received signal strength indication which is used widely in WSN. The developed tracking system is designed for continuous estimation of the robot’s trajectory. A WSN, which is composed of many very simple and cheap wireless sensor nodes, is deployed at a specific region of interest. The wireless sensor nodes collect RSSI information sent by mobile robots. A range-based data fusion scheme is used to estimate the robot’s trajectory. Moreover, a Kalman filter is designed to improve tracking accuracy. Experiments are provided to assess the performance of the proposed scheme.

Effects of Low- Versus High-Fidelity Simulations on the Cognitive Burden and Performance of Entry-Level Paramedicine Students: A Mixed-Methods Comparison Trial Using Eye-Tracking, Continuous Heart Rate, Difficulty Rating Scales, Video Observation and Interviews.

Science.gov (United States)

Mills, Brennen W; Carter, Owen B-J; Rudd, Cobie J; Claxton, Louise A; Ross, Nathan P; Strobel, Natalie A

2016-02-01

High-fidelity simulation-based training is often avoided for early-stage students because of the assumption that while practicing newly learned skills, they are ill suited to processing multiple demands, which can lead to "cognitive overload" and poorer learning outcomes. We tested this assumption using a mixed-methods experimental design manipulating psychological immersion. Thirty-nine randomly assigned first-year paramedicine students completed low- or high-environmental fidelity simulations [low-environmental fidelity simulations (LF(en)S) vs. high-environmental fidelity simulation (HF(en)S)] involving a manikin with obstructed airway (SimMan3G). Psychological immersion and cognitive burden were determined via continuous heart rate, eye tracking, self-report questionnaire (National Aeronautics and Space Administration Task Load Index), independent observation, and postsimulation interviews. Performance was assessed by successful location of obstruction and time-to-termination. Eye tracking confirmed that students attended to multiple, concurrent stimuli in HF(en)S and interviews consistently suggested that they experienced greater psychological immersion and cognitive burden than their LF(en)S counterparts. This was confirmed by significantly higher mean heart rate (P cognitive burden but this has considerable educational merit.

Radio Tracking Fish with Small Unmanned Aircraft Systems (sUAS).

Science.gov (United States)

Dahlgren, R. P.; Anderson, K. R.; Hanson, L.; Pinsker, E. A.; Jonsson, J.; Chapman, D. C.; Witten, D. M.; O'Connor, K. A.

2017-12-01

Tracking radio tagged fish by boat or on foot in riverine systems is difficult and time consuming, particularly in large braided island complexes, shallow wetlands, and rocky reaches. Invasive Asian carp are commonly found in these hard to reach areas, but their near-surface feeding behavior makes radio tracking possible. To identify new methods of fish tracking that could same time and money, this study tested the feasibility of tracking Asian carp with Small Unmanned Aerial Systems (sUAS) in areas generally inaccessible to traditional tracking equipment. The U.S. Geological Survey worked with NanoElectromagnetics LLC and WWR Development to create and integrate a lightweight custom radio receiver, directional antenna, and accompanying software into a sUAS platform. The receiver includes independent GPS, software defined radio, and compass. The NASA Ames Research Center (ARC) completed payload integration, electromagnetic-interference and airworthiness testing, and provided a DJI Matrice 600 sUAS for this study. Additionally, ARC provided subject matter experts, airworthiness and flight readiness evaluation, and flight test facilities during preparation; and a pilot, range safety officer, and aircraft engineer during field deployment. Results demonstrate that this custom sUAS and sensor combination can detect radio tags at 100m above ground level and at horizontal ranges of 100m and 300m, with operators in either onshore or offshore locations. With this combination of sUAS and radio receiver, fish can be tracked in areas previously inaccessible and during flooding, providing new insights into riverine fish movement and habitat utilization.

Object Tracking with LiDAR: Monitoring Taxiing and Landing Aircraft

Directory of Open Access Journals (Sweden)

Zoltan Koppanyi

2018-02-01

Full Text Available Mobile light detection and ranging (LiDAR sensors used in car navigation and robotics, such as the Velodyne’s VLP-16 and HDL-32E, allow for sensing the surroundings of the platform with high temporal resolution to detect obstacles, tracking objects and support path planning. This study investigates the feasibility of using LiDAR sensors for tracking taxiing or landing aircraft close to the ground to improve airport safety. A prototype system was developed and installed at an airfield to capture point clouds to monitor aircraft operations. One of the challenges of accurate object tracking using the Velodyne sensors is the relatively small vertical field of view (30°, 41.3° and angular resolution (1.33°, 2°, resulting in a small number of points of the tracked object. The point density decreases with the object–sensor distance, and is already sparse at a moderate range of 30–40 m. The paper introduces our model-based tracking algorithms, including volume minimization and cube trajectories, to address the optimal estimation of object motion and tracking based on sparse point clouds. Using a network of sensors, multiple tests were conducted at an airport to assess the performance of the demonstration system and the algorithms developed. The investigation was focused on monitoring small aircraft moving on runways and taxiways, and the results indicate less than 0.7 m/s and 17 cm velocity and positioning accuracy achieved, respectively. Overall, based on our findings, this technology is promising not only for aircraft monitoring but for airport applications.

Real-time tumor tracking using implanted positron emission markers: Concept and simulation study

International Nuclear Information System (INIS)

Xu Tong; Wong, Jerry T.; Shikhaliev, Polad M.; Ducote, Justin L.; Al-Ghazi, Muthana S.; Molloi, Sabee

2006-01-01

The delivery accuracy of radiation therapy for pulmonary and abdominal tumors suffers from tumor motion due to respiration. Respiratory gating should be applied to avoid the use of a large target volume margin that results in a substantial dose to the surrounding normal tissue. Precise respiratory gating requires the exact spatial position of the tumor to be determined in real time during treatment. Usually, fiducial markers are implanted inside or next to the tumor to provide both accurate patient setup and real-time tumor tracking. However, current tumor tracking systems require either substantial x-ray exposure to the patient or large fiducial markers that limit the value of their application for pulmonary tumors. We propose a real-time tumor tracking system using implanted positron emission markers (PeTrack). Each marker will be labeled with low activity positron emitting isotopes, such as 124 I, 74 As, or 84 Rb. These isotopes have half-lives comparable to the duration of radiation therapy (from a few days to a few weeks). The size of the proposed PeTrack marker will be 0.5-0.8 mm, which is approximately one-half the size of markers currently employed in other techniques. By detecting annihilation gammas using position-sensitive detectors, multiple positron emission markers can be tracked in real time. A multimarker localization algorithm was developed using an Expectation-Maximization clustering technique. A Monte Carlo simulation model was developed for the PeTrack system. Patient dose, detector sensitivity, and scatter fraction were evaluated. Depending on the isotope, the lifetime dose from a 3.7 MBq PeTrack marker was determined to be 0.7-5.0 Gy at 10 mm from the marker. At the center of the field of view (FOV), the sensitivity of the PeTrack system was 240-320 counts/s per 1 MBq marker activity within a 30 cm thick patient. The sensitivity was reduced by 45% when the marker was near the edge of the FOV. The scatter fraction ranged from 12% ( 124 I, 74 As

Vacuum effect on the etch induction time and registration sensitivity of polymer track detectors

International Nuclear Information System (INIS)

Csige, I.; Hunyadi, I.; Somogyi, G.

1988-01-01

The effect of a vacuum on etch induction time and track etch rate ratio of some polymer track detectors was studied systematically with alpha particles of different energies. It was found that the etch induction time increases, and the track etch rate ratio decreases, drastically when the detectors were irradiated in a vacuum and also kept in a vacuum for a few hours before and for a few minutes after the irradiation. These times proved to be characteristic for the outgassing of oxygen from the sheets and the stabilization of latent tracks, respectively. The role of oxygen in latent track formation is discussed. We have found that the vacuum effect is most significant near the surface. Its diminution with depth depends on the time of outgassing in accordance with the time variation of the dissolved oxygen concentration profile inside the sheets. (author)

Vacuum effect on the etch induction time and registration sensitivity of polymer track detectors

Energy Technology Data Exchange (ETDEWEB)

Csige, I.; Hunyadi, I.; Somogyi, G. (Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete); Fujii, M. (Institute of Space and Astronautical Science, Sagamihara (Japan))

1988-01-01

The effect of a vacuum on etch induction time and track etch rate ratio of some polymer track detectors was studied systematically with alpha particles of different energies. It was found that the etch induction time increases, and the track etch rate ratio decreases, drastically when the detectors were irradiated in a vacuum and also kept in a vacuum for a few hours before and for a few minutes after the irradiation. These times proved to be characteristic for the outgassing of oxygen from the sheets and the stabilization of latent tracks, respectively. The role of oxygen in latent track formation is discussed. We have found that the vacuum effect is most significant near the surface. Its diminution with depth depends on the time of outgassing in accordance with the time variation of the dissolved oxygen concentration profile inside the sheets. (author).

Image analysis used to count and measure etched tracks from ionizing radiation

Science.gov (United States)

Blanford, George E.; Schulz, Cindy K.

1995-01-01

of plastic dosimeters is at an early stage of development, results are encouraging. The dosimeter was etched in 6.25 N NaOH at 70 deg C for 16 h. We took 200x secondary electron images of the sample and used the NIH Image software to count and measure major and minor diameters of the etched tracks. We calculated the relative track etch rate from a formula that relates it to the major and minor diameters. We made a histogram of the number of tracks versus their relative etch rate. The relative track etching rate is proportional to the linear energy transfer of the particle. With appropriate calibration experiments, the histogram could be used to calculate the radiation dose.

Processor for Real-Time Atmospheric Compensation in Long-Range Imaging, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Long-range imaging is a critical component to many NASA applications including range surveillance, launch tracking, and astronomical observation. However,...

A fast track trigger processor for the OPAL detector at LEP

International Nuclear Information System (INIS)

Carter, A.A.; Jaroslawski, S.; Wagner, A.

1986-01-01

A fast hardware track trigger processor being built for the OPAL experiment is described. The processor will analyse data from the central drift chambers of OPAL to determine whether any tracks come from the interaction region, and thereby eliminate background events. The processor will find tracks over a large angular range, vertical strokecos thetavertical stroke < or approx. 0.95. The design of the processor is described, together with a brief account of its hardware implementation for OPAL. The results of feasibility studies are also presented. (orig.)

Application of long-range order to predict unfolding rates of two-state proteins.

Science.gov (United States)

Harihar, B; Selvaraj, S

2011-03-01

Predicting the experimental unfolding rates of two-state proteins and models describing the unfolding rates of these proteins is quite limited because of the complexity present in the unfolding mechanism and the lack of experimental unfolding data compared with folding data. In this work, 25 two-state proteins characterized by Maxwell et al. (Protein Sci 2005;14:602–616) using a consensus set of experimental conditions were taken, and the parameter long-range order (LRO) derived from their three-dimensional structures were related with their experimental unfolding rates ln(k(u)). From the total data set of 30 proteins used by Maxwell et al. (Protein Sci 2005;14:602–616), five slow-unfolding proteins with very low unfolding rates were considered to be outliers and were not included in our data set. Except all beta structural class, LRO of both the all-alpha and mixed-class proteins showed a strong inverse correlation of r = -0.99 and -0.88, respectively, with experimental ln(k(u)). LRO shows a correlation of -0.62 with experimental ln(k(u)) for all-beta proteins. For predicting the unfolding rates, a simple statistical method has been used and linear regression equations were developed for individual structural classes of proteins using LRO, and the results obtained showed a better agreement with experimental results. Copyright © 2010 Wiley-Liss, Inc.

GPU implementations of online track finding algorithms at PANDA

Energy Technology Data Exchange (ETDEWEB)

Herten, Andreas; Stockmanns, Tobias; Ritman, James [Institut fuer Kernphysik, Forschungszentrum Juelich GmbH (Germany); Adinetz, Andrew; Pleiter, Dirk [Juelich Supercomputing Centre, Forschungszentrum Juelich GmbH (Germany); Kraus, Jiri [NVIDIA GmbH (Germany); Collaboration: PANDA-Collaboration

2014-07-01

The PANDA experiment is a hadron physics experiment that will investigate antiproton annihilation in the charm quark mass region. The experiment is now being constructed as one of the main parts of the FAIR facility. At an event rate of 2 . 10{sup 7}/s a data rate of 200 GB/s is expected. A reduction of three orders of magnitude is required in order to save the data for further offline analysis. Since signal and background processes at PANDA have similar signatures, no hardware-level trigger is foreseen for the experiment. Instead, a fast online event filter is substituting this element. We investigate the possibility of using graphics processing units (GPUs) for the online tracking part of this task. Researched algorithms are a Hough Transform, a track finder involving Riemann surfaces, and the novel, PANDA-specific Triplet Finder. This talk shows selected advances in the implementations as well as performance evaluations of the GPU tracking algorithms to be used at the PANDA experiment.

The FTK: A Hardware Track Finder for the ATLAS Trigger

CERN Document Server

Alison, J; Anderson, J; Andreani, A; Andreazza, A; Annovi, A; Antonelli, M; Atkinson, M; Auerbach, B; Baines, J; Barberio, E; Beccherle, R; Beretta, M; Biesuz, N V; Blair, R; Blazey, G; Bogdan, M; Boveia, A; Britzger, D; Bryant, P; Burghgrave, B; Calderini, G; Cavaliere, V; Cavasinni, V; Chakraborty, D; Chang, P; Cheng, Y; Cipriani, R; Citraro, S; Citterio, M; Crescioli, F; Dell'Orso, M; Donati, S; Dondero, P; Drake, G; Gadomski, S; Gatta, M; Gentsos, C; Giannetti, P; Giulini, M; Gkaitatzis, S; Howarth, J W; Iizawa, T; Kapliy, A; Kasten, M; Kim, Y K; Kimura, N; Klimkovich, T; Kordas, K; Korikawa, T; Krizka, K; Kubota, T; Lanza, A; Lasagni, F; Liberali, V; Li, H L; Love, J; Luciano, P; Luongo, C; Magalotti, D; Melachrinos, C; Meroni, C; Mitani, T; Negri, A; Neroutsos, P; Neubauer, M; Nikolaidis, S; Okumura, Y; Pandini, C; Penning, B; Petridou, C; Piendibene, M; Proudfoot, J; Rados, P; Roda, C; Rossi, E; Sakurai, Y; Sampsonidis, D; Sampsonidou, D; Schmitt, S; Schoening, A; Shochet, M; Shojaii, S; Soltveit, H; Sotiropoulou, C L; Stabile, A; Tang, F; Testa, M; Tompkins, L; Vercesi, V; Villa, M; Volpi, G; Webster, J; Wu, X; Yorita, K; Yurkewicz, A; Zeng, J C; Zhang, J

2014-01-01

The ATLAS experiment trigger system is designed to reduce the event rate, at the LHC design luminosity of 1034 cm-2 s-1, from the nominal bunch crossing rate of 40 MHz to less than 1 kHz for permanent storage. During Run 1, the LHC has performed exceptionally well, routinely exceeding the design luminosity. From 2015 the LHC is due to operate with higher still luminosities. This will place a significant load on the High Level Trigger system, both due to the need for more sophisticated algorithms to reject background, and from the larger data volumes that will need to be processed. The Fast TracKer is a hardware upgrade for Run 2, consisting of a custom electronics system that will operate at the full rate for Level-1 accepted events of 100 kHz and provide high quality tracks at the beginning of processing in the High Level Trigger. This will perform track reconstruction using hardware with massive parallelism using associative memories and FPGAs. The availability of the full tracking information will enable r...

Track reconstruction principle in ALICE for LHC run I and run II

CERN Multimedia

Maire, Antonin

2011-01-01

Principles of tracking for an ALICE event, showing the three successive paths allowing to build a track and refine its parameters. Numbers ranging from 1 to 10 mention the bits that are activated in case of success during the propgation of the Kalman filter at the considered stage.

Face Recognition and Tracking in Videos

Directory of Open Access Journals (Sweden)

Swapnil Vitthal Tathe

2017-07-01

Full Text Available Advancement in computer vision technology and availability of video capturing devices such as surveillance cameras has evoked new video processing applications. The research in video face recognition is mostly biased towards law enforcement applications. Applications involves human recognition based on face and iris, human computer interaction, behavior analysis, video surveillance etc. This paper presents face tracking framework that is capable of face detection using Haar features, recognition using Gabor feature extraction, matching using correlation score and tracking using Kalman filter. The method has good recognition rate for real-life videos and robust performance to changes due to illumination, environmental factors, scale, pose and orientations.

Performance of ATLAS tracking detector

CERN Document Server

Lacuesta, V; The ATLAS collaboration

2012-01-01

The track and vertex reconstruction algorithms of the ATLAS Inner Detector have demonstrated excellent performance in the early data from the LHC. However, the rapidly increas- ing number of interactions per bunch crossing introduces new challenges both in computational aspects and physics performance. The combination of both silicon and gas based detectors provides high precision impact parameter and momentum measurement of charged particles, with high efficiency and small fake rate. Vertex reconstruction is used to identify with high efficiency the hard scattering process and to measure the amount of pile-up interactions, both aspects are cru- cial for many physics analyses. The performance of track and vertex reconstruction efficiency and resolution achieved in the 2011 and 2012 data-taking period are presented.

Exploration and extension of an improved Riemann track fitting algorithm

Science.gov (United States)

Strandlie, A.; Frühwirth, R.

2017-09-01

Recently, a new Riemann track fit which operates on translated and scaled measurements has been proposed. This study shows that the new Riemann fit is virtually as precise as popular approaches such as the Kalman filter or an iterative non-linear track fitting procedure, and significantly more precise than other, non-iterative circular track fitting approaches over a large range of measurement uncertainties. The fit is then extended in two directions: first, the measurements are allowed to lie on plane sensors of arbitrary orientation; second, the full error propagation from the measurements to the estimated circle parameters is computed. The covariance matrix of the estimated track parameters can therefore be computed without recourse to asymptotic properties, and is consequently valid for any number of observation. It does, however, assume normally distributed measurement errors. The calculations are validated on a simulated track sample and show excellent agreement with the theoretical expectations.

Track reconstruction at the ILC: the ILD tracking software

International Nuclear Information System (INIS)

Gaede, Frank; Aplin, Steven; Rosemann, Christoph; Voutsinas, Georgios; Glattauer, Robin

2014-01-01

One of the key requirements for Higgs physics at the International Linear Collider ILC is excellent track reconstruction with very good momentum and impact parameter resolution. ILD is one of the two detector concepts at the ILC. Its central tracking system comprises of an outer Si-tracker, a highly granular TPC, an intermediate silicon tracker and a pixel vertex detector, and it is complemented by silicon tracking disks in the forward direction. Large hit densities from beam induced coherent electron-positron pairs at the ILC pose an additional challenge to the pattern recognition algorithms. We present the recently developed new ILD tracking software, the pattern recognition algorithms that are using clustering techniques, Cellular Automatons and Kalman filter based track extrapolation. The performance of the ILD tracking system is evaluated using a detailed simulation including dead material, gaps and imperfections.

Mechanical response of AA7075 aluminum alloy over a wide range of temperatures and strain rates

Energy Technology Data Exchange (ETDEWEB)

Jin, Z.; Cassada, W.A. [Reynolds Metals Co., Chester, VA (United States). Corp. Res. and Dev.; Cady, C.M.; Gray, G.T. III

2000-07-01

The influence of temperature and strain rate on the flow stress and work hardening rate of a 7075 aluminum alloy was studied under compressive loading over the temperature range from 23 C to 470 C, and strain rates from 0.001 s{sup -1} and 2100 s{sup -1}. While the temperature dependence of the flow stress was found to be most significant at temperatures below 300 C, the strain rate dependence of the flow stress was found to be pronounced at temperatures above 23 C. Concurrently, the work hardening rate decreases significantly with increasing temperature between 23 C and 300 C and increases slightly at higher temperatures. The minimum work hardening rate is observed to occur at temperatures between 200 C and 300 C and shift to higher temperatures with increasing strain rate. A negative strain rate dependence of work hardening rate was observed at 23 C, although a positive strain rate dependence of work hardening rate occurs at higher temperatures. Analysis of the experimental data revealed three deformation regimes. (orig.)

A novel laser alignment system for tracking detectors using transparent silicon strip sensors

International Nuclear Information System (INIS)

Blum, W.; Kroha, H.; Widmann, P.

1995-02-01

Modern large-area precision tracking detectors require increasing accuracy of the geometrical alignment over large distances. A novel optical multi-point alignment system has been developed for the muon spectrometer of the ATLAS detector at the Large Hadron Collider. The system uses collimated laser beams as alignment references which are monitored by semi-transparent optical position sensors. The custom designed sensors provide very precise and uniform position information on the order of 1 μm over a wide measurement range. At suitable laser wavelengths, produced by laser diodes, transmission rates above 90% have been achieved which allow to align more than 30 sensors along one laser beam. With this capability and equipped with integrated readout electronics, the alignment system offers high flexibility for precision applications in a wide range of detector systems. (orig.)

Location detection and tracking of moving targets by a 2D IR-UWB radar system.

Science.gov (United States)

Nguyen, Van-Han; Pyun, Jae-Young

2015-03-19

In indoor environments, the Global Positioning System (GPS) and long-range tracking radar systems are not optimal, because of signal propagation limitations in the indoor environment. In recent years, the use of ultra-wide band (UWB) technology has become a possible solution for object detection, localization and tracking in indoor environments, because of its high range resolution, compact size and low cost. This paper presents improved target detection and tracking techniques for moving objects with impulse-radio UWB (IR-UWB) radar in a short-range indoor area. This is achieved through signal-processing steps, such as clutter reduction, target detection, target localization and tracking. In this paper, we introduce a new combination consisting of our proposed signal-processing procedures. In the clutter-reduction step, a filtering method that uses a Kalman filter (KF) is proposed. Then, in the target detection step, a modification of the conventional CLEAN algorithm which is used to estimate the impulse response from observation region is applied for the advanced elimination of false alarms. Then, the output is fed into the target localization and tracking step, in which the target location and trajectory are determined and tracked by using unscented KF in two-dimensional coordinates. In each step, the proposed methods are compared to conventional methods to demonstrate the differences in performance. The experiments are carried out using actual IR-UWB radar under different scenarios. The results verify that the proposed methods can improve the probability and efficiency of target detection and tracking.