The extended reciprocity: Strong belief outperforms persistence.

Science.gov (United States)

Kurokawa, Shun

2017-05-21

The existence of cooperation is a mysterious phenomenon and demands explanation, and direct reciprocity is one key potential explanation for the evolution of cooperation. Direct reciprocity allows cooperation to evolve for cooperators who switch their behavior on the basis of information about the opponent's behavior. Here, relevant to direct reciprocity is information deficiency. When the opponent's last move is unknown, how should players behave? One possibility is to choose cooperation with some default probability without using any further information. In fact, our previous paper (Kurokawa, 2016a) examined this strategy. However, there might be beneficial information other than the opponent's last move. A subsequent study of ours (Kurokawa, 2017) examined the strategy which uses the own last move when the opponent's last move is unknown, and revealed that referring to the own move and trying to imitate it when information is absent is beneficial. Is there any other beneficial information else? How about strong belief (i.e., have infinite memory and believe that the opponent's behavior is unchanged)? Here, we examine the evolution of strategies with strong belief. Analyzing the repeated prisoner's dilemma game and using evolutionarily stable strategy (ESS) analysis against an invasion by unconditional defectors, we find the strategy with strong belief is more likely to evolve than the strategy which does not use information other than the opponent player's last move and more likely to evolve than the strategy which uses not only the opponent player's last move but also the own last move. Strong belief produces the extended reciprocity and facilitates the evolution of cooperation. Additionally, we consider the two strategies game between strategies with strong belief and any strategy, and we consider the four strategies game in which unconditional cooperators, unconditional defectors, pessimistic reciprocators with strong belief, and optimistic reciprocators with

Airborne system for mapping and tracking extended gamma ray sources

International Nuclear Information System (INIS)

Stuart, T.P.; Hendricks, T.J.; Wallace, G.G.; Cleland, J.R.

1976-01-01

An airborne system was developed for mapping and tracking extended sources of airborne or terrestrially distributed γ-ray emitters. The system records 300 channel γ-ray spectral data every three seconds on magnetic tape. Computer programs have been written to isolate the contribution from the particular radionuclide of interest. Aircraft position as sensed by a microwave ranging system is recorded every second on magnetic tape. Measurements of airborne stack releases of 41 A concentrations versus time or aircraft position agree well with computer code predictions

Tracking single dynamic MEG dipole sources using the projected Extended Kalman Filter.

Science.gov (United States)

Yao, Yuchen; Swindlehurst, A Lee

2011-01-01

This paper presents two new algorithms based on the Extended Kalman Filter (EKF) for tracking the parameters of single dynamic magnetoencephalography (MEG) dipole sources. We assume a dynamic MEG dipole source with possibly both time-varying location and dipole orientation. The standard EKF-based tracking algorithm performs well under the assumption that the dipole source components vary in time as a Gauss-Markov process, provided that the background noise is temporally stationary. We propose a Projected-EKF algorithm that is adapted to a more forgiving condition where the background noise is temporally nonstationary, as well as a Projected-GLS-EKF algorithm that works even more universally, when the dipole components vary arbitrarily from one sample to the next.

Leader-Follower Tracking System for Agricultural Vehicles: Fusion of Laser and Odometry Positioning Using Extended Kalman Filter

Directory of Open Access Journals (Sweden)

Zhang Lin Huan

2015-03-01

Full Text Available The aim of this research was to develop a safe human-driven and autonomous leader-follower tracking system for an autonomous tractor. To enable the tracking system, a laser range finder (LRF-based landmark detection system was designed to observe the relative position between a leader and a follower used in agricultural operations. The virtual follower-based formation-tracking algorithm was developed to minimize tracking errors and ensure safety. An extended Kalman filter (EKF was implemented for fusing LRF and odometry position to ensure stability of tracking in noisy farmland conditions. Simulations were conducted for tracking the leader in small and large sinusoidal curved paths. Simulated results verified high accuracy of formation tracking, stable velocity, and regulated steering angle of the follower. The tracking method confirmed the follower could follow the leader with a required formation safely and steadily in noisy conditions. The EKF helped to improve observation accuracy, velocity, and steering angle stability of the follower. As a result of the improved accuracy of observation and motion action, the tracking performance for lateral, longitudinal, and heading were also improved after the EKF was implemented in the tracking system.

Maximum-likelihood-based extended-source spatial acquisition and tracking for planetary optical communications

Science.gov (United States)

Tsou, Haiping; Yan, Tsun-Yee

1999-04-01

This paper describes an extended-source spatial acquisition and tracking scheme for planetary optical communications. This scheme uses the Sun-lit Earth image as the beacon signal, which can be computed according to the current Sun-Earth-Probe angle from a pre-stored Earth image or a received snapshot taken by other Earth-orbiting satellite. Onboard the spacecraft, the reference image is correlated in the transform domain with the received image obtained from a detector array, which is assumed to have each of its pixels corrupted by an independent additive white Gaussian noise. The coordinate of the ground station is acquired and tracked, respectively, by an open-loop acquisition algorithm and a closed-loop tracking algorithm derived from the maximum likelihood criterion. As shown in the paper, the optimal spatial acquisition requires solving two nonlinear equations, or iteratively solving their linearized variants, to estimate the coordinate when translation in the relative positions of onboard and ground transceivers is considered. Similar assumption of linearization leads to the closed-loop spatial tracking algorithm in which the loop feedback signals can be derived from the weighted transform-domain correlation. Numerical results using a sample Sun-lit Earth image demonstrate that sub-pixel resolutions can be achieved by this scheme in a high disturbance environment.

Performance enhancement for a GPS vector-tracking loop utilizing an adaptive iterated extended Kalman filter.

Science.gov (United States)

Chen, Xiyuan; Wang, Xiying; Xu, Yuan

2014-12-09

This paper deals with the problem of state estimation for the vector-tracking loop of a software-defined Global Positioning System (GPS) receiver. For a nonlinear system that has the model error and white Gaussian noise, a noise statistics estimator is used to estimate the model error, and based on this, a modified iterated extended Kalman filter (IEKF) named adaptive iterated Kalman filter (AIEKF) is proposed. A vector-tracking GPS receiver utilizing AIEKF is implemented to evaluate the performance of the proposed method. Through road tests, it is shown that the proposed method has an obvious accuracy advantage over the IEKF and Adaptive Extended Kalman filter (AEKF) in position determination. The results show that the proposed method is effective to reduce the root-mean-square error (RMSE) of position (including longitude, latitude and altitude). Comparing with EKF, the position RMSE values of AIEKF are reduced by about 45.1%, 40.9% and 54.6% in the east, north and up directions, respectively. Comparing with IEKF, the position RMSE values of AIEKF are reduced by about 25.7%, 19.3% and 35.7% in the east, north and up directions, respectively. Compared with AEKF, the position RMSE values of AIEKF are reduced by about 21.6%, 15.5% and 30.7% in the east, north and up directions, respectively.

Extending EGS With SVG for Track Visualization

International Nuclear Information System (INIS)

Cowan, R.

2004-01-01

The Electron Gamma Shower (EGS) Code System at SLAC is designed to simulate the flow of electrons, positrons and photons through matter at a wide range of energies. It has a large user base among the high-energy physics community and is often used as a teaching tool through a Web interface that allows program input and output. Our work aims to improve the user interaction and shower visualization model of the EGS Web interface. Currently, manipulation of the graphical output (a GIF file) is limited to simple operations like panning and zooming, and each such operation requires server-side calculations. We use SVG (Scalable Vector Graphics) to allow a much richer set of operations, letting users select a track and visualize it with the aid of 3-D rotations, adjustable particle display intensities, panning and zooming etc. A considerable advantage of our method is that once a track is selected for visualization, all further manipulations on that track can be done client-side without requiring server-side calculations. We hence combine the advantages of the SVG format (powerful interaction models over the Web) with those of conventional image formats (file size independent of scene complexity) to allow a composite set of operations for users, and enhance the value of EGS as a pedagogical tool

Relation of extended Van Hove singularities to high-temperature superconductivity within strong-coupling theory

International Nuclear Information System (INIS)

Radtke, R.J.; Norman, M.R.

1994-01-01

Recent angle-resolved photoemission (ARPES) experiments have indicated that the electronic dispersion in some of the cuprates possesses an extended saddle point near the Fermi level which gives rise to a density of states that diverges like a power law instead of the weaker logarithmic divergence usually considered. We investigate whether this strong singularity can give rise to high transition temperatures by computing the critical temperature T c and isotope effect coefficient α within a strong-coupling Eliashberg theory which accounts for the full energy variation of the density of states. Using band structures extracted from ARPES measurements, we demonstrate that, while the weak-coupling solutions suggest a strong influence of the strength of the Van Hove singularity on T c and α, strong-coupling solutions show less sensitivity to the singularity strength and do not support the hypothesis that band-structure effects alone can account for either the large T c 's or the different T c 's within the copper oxide family. This conclusion is supported when our results are plotted as a function of the physically relevant self-consistent coupling constant, which shows universal behavior at very strong coupling

Fusing inertial sensor data in an extended Kalman filter for 3D camera tracking.

Science.gov (United States)

Erdem, Arif Tanju; Ercan, Ali Özer

2015-02-01

In a setup where camera measurements are used to estimate 3D egomotion in an extended Kalman filter (EKF) framework, it is well-known that inertial sensors (i.e., accelerometers and gyroscopes) are especially useful when the camera undergoes fast motion. Inertial sensor data can be fused at the EKF with the camera measurements in either the correction stage (as measurement inputs) or the prediction stage (as control inputs). In general, only one type of inertial sensor is employed in the EKF in the literature, or when both are employed they are both fused in the same stage. In this paper, we provide an extensive performance comparison of every possible combination of fusing accelerometer and gyroscope data as control or measurement inputs using the same data set collected at different motion speeds. In particular, we compare the performances of different approaches based on 3D pose errors, in addition to camera reprojection errors commonly found in the literature, which provides further insight into the strengths and weaknesses of different approaches. We show using both simulated and real data that it is always better to fuse both sensors in the measurement stage and that in particular, accelerometer helps more with the 3D position tracking accuracy, whereas gyroscope helps more with the 3D orientation tracking accuracy. We also propose a simulated data generation method, which is beneficial for the design and validation of tracking algorithms involving both camera and inertial measurement unit measurements in general.

Extended Kalman Filtering to estimate temperature and irradiation for maximum power point tracking of a photovoltaic module

International Nuclear Information System (INIS)

Docimo, D.J.; Ghanaatpishe, M.; Mamun, A.

2017-01-01

This paper develops an algorithm for estimating photovoltaic (PV) module temperature and effective irradiation level. The power output of a PV system depends directly on both of these states. Estimating the temperature and irradiation allows for improved state-based control methods while eliminating the need of additional sensors. Thermal models and irradiation estimators have been developed in the literature, but none incorporate feedback for estimation. This paper outlines an Extended Kalman Filter for temperature and irradiation estimation. These estimates are, in turn, used within a novel state-based controller that tracks the maximum power point of the PV system. Simulation results indicate this state-based controller provides up to an 8.5% increase in energy produced per day as compared to an impedance matching controller. A sensitivity analysis is provided to examine the impact state estimate errors have on the ability to find the optimal operating point of the PV system. - Highlights: • Developed a temperature and irradiation estimator for photovoltaic systems. • Designed an Extended Kalman Filter to handle model and measurement uncertainty. • Developed a state-based controller for maximum power point tracking (MPPT). • Validated combined estimator/controller algorithm for different weather conditions. • Algorithm increases energy captured up to 8.5% over traditional MPPT algorithms.

A New Method for State of Charge Estimation of Lithium-Ion Battery Based on Strong Tracking Cubature Kalman Filter

Directory of Open Access Journals (Sweden)

Bizhong Xia

2015-11-01

Full Text Available The estimation of state of charge (SOC is a crucial evaluation index in a battery management system (BMS. The value of SOC indicates the remaining capacity of a battery, which provides a good guarantee of safety and reliability of battery operation. It is difficult to get an accurate value of the SOC, being one of the inner states. In this paper, a strong tracking cubature Kalman filter (STCKF based on the cubature Kalman filter is presented to perform accurate and reliable SOC estimation. The STCKF algorithm can adjust gain matrix online by introducing fading factor to the state estimation covariance matrix. The typical second-order resistor-capacitor model is used as the battery’s equivalent circuit model to dynamically simulate characteristics of the battery. The exponential-function fitting method accomplishes the task of relevant parameters identification. Then, the developed STCKF algorithm has been introduced in detail and verified under different operation current profiles such as Dynamic Stress Test (DST and New European Driving Cycle (NEDC. Making a comparison with extended Kalman filter (EKF and CKF algorithm, the experimental results show the merits of the STCKF algorithm in SOC estimation accuracy and robustness.

Model-based extended quaternion Kalman filter to inertial orientation tracking of arbitrary kinematic chains.

Science.gov (United States)

Szczęsna, Agnieszka; Pruszowski, Przemysław

2016-01-01

Inertial orientation tracking is still an area of active research, especially in the context of out-door, real-time, human motion capture. Existing systems either propose loosely coupled tracking approaches where each segment is considered independently, taking the resulting drawbacks into account, or tightly coupled solutions that are limited to a fixed chain with few segments. Such solutions have no flexibility to change the skeleton structure, are dedicated to a specific set of joints, and have high computational complexity. This paper describes the proposal of a new model-based extended quaternion Kalman filter that allows for estimation of orientation based on outputs from the inertial measurements unit sensors. The filter considers interdependencies resulting from the construction of the kinematic chain so that the orientation estimation is more accurate. The proposed solution is a universal filter that does not predetermine the degree of freedom at the connections between segments of the model. To validation the motion of 3-segments single link pendulum captured by optical motion capture system is used. The next step in the research will be to use this method for inertial motion capture with a human skeleton model.

Advanced data assimilation in strongly nonlinear dynamical systems

Science.gov (United States)

Miller, Robert N.; Ghil, Michael; Gauthiez, Francois

1994-01-01

Advanced data assimilation methods are applied to simple but highly nonlinear problems. The dynamical systems studied here are the stochastically forced double well and the Lorenz model. In both systems, linear approximation of the dynamics about the critical points near which regime transitions occur is not always sufficient to track their occurrence or nonoccurrence. Straightforward application of the extended Kalman filter yields mixed results. The ability of the extended Kalman filter to track transitions of the double-well system from one stable critical point to the other depends on the frequency and accuracy of the observations relative to the mean-square amplitude of the stochastic forcing. The ability of the filter to track the chaotic trajectories of the Lorenz model is limited to short times, as is the ability of strong-constraint variational methods. Examples are given to illustrate the difficulties involved, and qualitative explanations for these difficulties are provided. Three generalizations of the extended Kalman filter are described. The first is based on inspection of the innovation sequence, that is, the successive differences between observations and forecasts; it works very well for the double-well problem. The second, an extension to fourth-order moments, yields excellent results for the Lorenz model but will be unwieldy when applied to models with high-dimensional state spaces. A third, more practical method--based on an empirical statistical model derived from a Monte Carlo simulation--is formulated, and shown to work very well. Weak-constraint methods can be made to perform satisfactorily in the context of these simple models, but such methods do not seem to generalize easily to practical models of the atmosphere and ocean. In particular, it is shown that the equations derived in the weak variational formulation are difficult to solve conveniently for large systems.

Real time eye tracking using Kalman extended spatio-temporal context learning

Science.gov (United States)

Munir, Farzeen; Minhas, Fayyaz ul Amir Asfar; Jalil, Abdul; Jeon, Moongu

2017-06-01

Real time eye tracking has numerous applications in human computer interaction such as a mouse cursor control in a computer system. It is useful for persons with muscular or motion impairments. However, tracking the movement of the eye is complicated by occlusion due to blinking, head movement, screen glare, rapid eye movements, etc. In this work, we present the algorithmic and construction details of a real time eye tracking system. Our proposed system is an extension of Spatio-Temporal context learning through Kalman Filtering. Spatio-Temporal Context Learning offers state of the art accuracy in general object tracking but its performance suffers due to object occlusion. Addition of the Kalman filter allows the proposed method to model the dynamics of the motion of the eye and provide robust eye tracking in cases of occlusion. We demonstrate the effectiveness of this tracking technique by controlling the computer cursor in real time by eye movements.

Extending Track Analysis from Animals in the Lab to Moving Objects Anywhere

NARCIS (Netherlands)

Dommelen, W. van; Laar, P.J.L.J. van de; Noldus, L.P.J.J.

2013-01-01

In this chapter we compare two application domains in which the tracking of objects and the analysis of their movements are core activities, viz. animal tracking and vessel tracking. More specifically, we investigate whether EthoVision XT, a research tool for video tracking and analysis of the

The TL fluence response to heavy charged particles using the track interaction model and track structure information

International Nuclear Information System (INIS)

Rodriguez-Villafuerte, M.; Avila, O.

2002-01-01

The extended track interaction model, ETIM, has recently been proposed to explain the TLD-100 fluence response of peak 5 to heavy ions. This model includes the track structure information through the use of the luminescent-centre occupation probability obtained from radial dose distributions produced by the ions as they travel through the dosemeter. In this work an implementation of ETIM using Monte Carlo techniques is presented. The simulation was applied to calculate the response of peak 5 of both sensitised and normal TLD-100 crystals to 2.6 and 6.8 MeV 4 He ions. The simulation shows that the TL-fluence response has a strong dependence on ion energy, in disagreement with experimental observations. In spite of this, good agreement between the simulated TL-fluence response calculated for the 6.8 MeV 4 He radial distributions and the experimental data for the two energies was achieved. (author)

Are ship tracks useful analogs for studying the aerosol indirect effect?

Science.gov (United States)

Christensen, M.; Toll, V.; Stephens, G. L.

2017-12-01

Vessels transiting the ocean sometimes leave their mark on the clouds - leaving behind reflective cloud lines, known as ship tracks. Ship tracks have been looked upon by some as a possible Rosetta Stone connecting the effects of changing aerosol over the ocean and cloud albedo effects on climate (Porch et al. 1990, Atmos. Enviorn., 1051-1059). In this research, we establish whether ship tracks, and volcano tracks - a natural analog, can be used to relate these cloud-scale perturbations to the aerosol effects occurring at larger regional-scales. Two databases containing over 1,500 ship and 900 volcano tracks, all carefully hand-selected from satellite imagery, are utilized; showing that ship tracks exhibit very similar cloud albedo effect responses to that of volcano tracks. For comparison, our global dataset utilises over 7 million CloudSat profiles consisting of single-layer marine warm cloud in which the retrievals are co-located with the MODerate Imaging Spectroradiometer (MODIS) product so that statistical relationships between aerosol and cloud can be computed over 4x4 degree regions. All datasets show the same key physical processes that govern the cloud-aerosol indirect effect, namely, the strong negative responses in cloud droplet size and the bidirectional responses in liquid water path and cloud albedo depending on the meteorological conditions. Finally, this analysis is extended to a comparison against several general circulation models where it is suggested that key processes such as cloud-top entrainment and evaporation that regulates against strong liquid water path responses are likely underrepresented in most models.

Fault diagnosis for the heat exchanger of the aircraft environmental control system based on the strong tracking filter.

Science.gov (United States)

Ma, Jian; Lu, Chen; Liu, Hongmei

2015-01-01

The aircraft environmental control system (ECS) is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system's efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF) and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF) and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger.

Fault diagnosis for the heat exchanger of the aircraft environmental control system based on the strong tracking filter.

Directory of Open Access Journals (Sweden)

Jian Ma

Full Text Available The aircraft environmental control system (ECS is a critical aircraft system, which provides the appropriate environmental conditions to ensure the safe transport of air passengers and equipment. The functionality and reliability of ECS have received increasing attention in recent years. The heat exchanger is a particularly significant component of the ECS, because its failure decreases the system's efficiency, which can lead to catastrophic consequences. Fault diagnosis of the heat exchanger is necessary to prevent risks. However, two problems hinder the implementation of the heat exchanger fault diagnosis in practice. First, the actual measured parameter of the heat exchanger cannot effectively reflect the fault occurrence, whereas the heat exchanger faults are usually depicted by utilizing the corresponding fault-related state parameters that cannot be measured directly. Second, both the traditional Extended Kalman Filter (EKF and the EKF-based Double Model Filter have certain disadvantages, such as sensitivity to modeling errors and difficulties in selection of initialization values. To solve the aforementioned problems, this paper presents a fault-related parameter adaptive estimation method based on strong tracking filter (STF and Modified Bayes classification algorithm for fault detection and failure mode classification of the heat exchanger, respectively. Heat exchanger fault simulation is conducted to generate fault data, through which the proposed methods are validated. The results demonstrate that the proposed methods are capable of providing accurate, stable, and rapid fault diagnosis of the heat exchanger.

Parameter estimation of a three-axis spacecraft simulator using recursive least-squares approach with tracking differentiator and Extended Kalman Filter

Science.gov (United States)

Xu, Zheyao; Qi, Naiming; Chen, Yukun

2015-12-01

Spacecraft simulators are widely used to study the dynamics, guidance, navigation, and control of a spacecraft on the ground. A spacecraft simulator can have three rotational degrees of freedom by using a spherical air-bearing to simulate a frictionless and micro-gravity space environment. The moment of inertia and center of mass are essential for control system design of ground-based three-axis spacecraft simulators. Unfortunately, they cannot be known precisely. This paper presents two approaches, i.e. a recursive least-squares (RLS) approach with tracking differentiator (TD) and Extended Kalman Filter (EKF) method, to estimate inertia parameters. The tracking differentiator (TD) filter the noise coupled with the measured signals and generate derivate of the measured signals. Combination of two TD filters in series obtains the angular accelerations that are required in RLS (TD-TD-RLS). Another method that does not need to estimate the angular accelerations is using the integrated form of dynamics equation. An extended TD (ETD) filter which can also generate the integration of the function of signals is presented for RLS (denoted as ETD-RLS). States and inertia parameters are estimated simultaneously using EKF. The observability is analyzed. All proposed methods are illustrated by simulations and experiments.

Neural network tracking and extension of positive tracking periods

Science.gov (United States)

Hanan, Jay C.; Chao, Tien-Hsin; Moreels, Pierre

2004-04-01

Feature detectors have been considered for the role of supplying additional information to a neural network tracker. The feature detector focuses on areas of the image with significant information. Basically, if a picture says a thousand words, the feature detectors are looking for the key phrases (keypoints). These keypoints are rotationally invariant and may be matched across frames. Application of these advanced feature detectors to the neural network tracking system at JPL has promising potential. As part of an ongoing program, an advanced feature detector was tested for augmentation of a neural network based tracker. The advance feature detector extended tracking periods in test sequences including aircraft tracking, rover tracking, and simulated Martian landing. Future directions of research are also discussed.

1st Workshop on Eye Tracking and Visualization

CERN Document Server

Chuang, Lewis; Fisher, Brian; Schmidt, Albrecht; Weiskopf, Daniel

2017-01-01

This book discusses research, methods, and recent developments in the interdisciplinary field that spans research in visualization, eye tracking, human-computer interaction, and psychology. It presents extended versions of papers from the First Workshop on Eye Tracking and Visualization (ETVIS), which was organized as a workshop of the IEEE VIS Conference 2015. Topics include visualization and visual analytics of eye-tracking data, metrics and cognitive models, eye-tracking experiments in the context of visualization interfaces, and eye tracking in 3D and immersive environments. The extended ETVIS papers are complemented by a chapter offering an overview of visualization approaches for analyzing eye-tracking data and a chapter that discusses electrooculography (EOG) as an alternative of acquiring information about eye movements. Covering scientific visualization, information visualization, and visual analytics, this book is a valuable resource for eye-tracking researchers within the visualization community.

Large N lattice QCD and its extended strong-weak connection to the hypersphere

International Nuclear Information System (INIS)

Christensen, Alexander S.; Myers, Joyce C.; Pedersen, Peter D.

2014-01-01

We calculate an effective Polyakov line action of QCD at large N c and large N f from a combined lattice strong coupling and hopping expansion working to second order in both, where the order is defined by the number of windings in the Polyakov line. We compare with the action, truncated at the same order, of continuum QCD on S 1 ×S d at weak coupling from one loop perturbation theory, and find that a large N c correspondence of equations of motion found in http://dx.doi.org/10.1007/JHEP10(2012)067 at leading order, can be extended to the next order. Throughout the paper, we review the background necessary for computing higher order corrections to the lattice effective action, in order to make higher order comparisons more straightforward

Elastic tracking versus neural network tracking for very high multiplicity problems

International Nuclear Information System (INIS)

Harlander, M.; Gyulassy, M.

1991-04-01

A new Elastic Tracking (ET) algorithm is proposed for finding tracks in very high multiplicity and noisy environments. It is based on a dynamical reinterpretation and generalization of the Radon transform and is related to elastic net algorithms for geometrical optimization. ET performs an adaptive nonlinear fit to noisy data with a variable number of tracks. Its numerics is more efficient than that of the traditional Radon or Hough transform method because it avoids binning of phase space and the costly search for valid minima. Spurious local minima are avoided in ET by introducing a time-dependent effective potential. The method is shown to be very robust to noise and measurement error and extends tracking capabilities to much higher track densities than possible via local road finding or even the novel Denby-Peterson neural network tracking algorithms. 12 refs., 2 figs

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)

Effect of strong disorder on three-dimensional chiral topological insulators: Phase diagrams, maps of the bulk invariant, and existence of topological extended bulk states

Science.gov (United States)

Song, Juntao; Fine, Carolyn; Prodan, Emil

2014-11-01

The effect of strong disorder on chiral-symmetric three-dimensional lattice models is investigated via analytical and numerical methods. The phase diagrams of the models are computed using the noncommutative winding number, as functions of disorder strength and model's parameters. The localized/delocalized characteristic of the quantum states is probed with level statistics analysis. Our study reconfirms the accurate quantization of the noncommutative winding number in the presence of strong disorder, and its effectiveness as a numerical tool. Extended bulk states are detected above and below the Fermi level, which are observed to undergo the so-called "levitation and pair annihilation" process when the system is driven through a topological transition. This suggests that the bulk invariant is carried by these extended states, in stark contrast with the one-dimensional case where the extended states are completely absent and the bulk invariant is carried by the localized states.

Extending Correlation Filter-Based Visual Tracking by Tree-Structured Ensemble and Spatial Windowing.

Science.gov (United States)

Gundogdu, Erhan; Ozkan, Huseyin; Alatan, A Aydin

2017-11-01

Correlation filters have been successfully used in visual tracking due to their modeling power and computational efficiency. However, the state-of-the-art correlation filter-based (CFB) tracking algorithms tend to quickly discard the previous poses of the target, since they consider only a single filter in their models. On the contrary, our approach is to register multiple CFB trackers for previous poses and exploit the registered knowledge when an appearance change occurs. To this end, we propose a novel tracking algorithm [of complexity O(D) ] based on a large ensemble of CFB trackers. The ensemble [of size O(2 D ) ] is organized over a binary tree (depth D ), and learns the target appearance subspaces such that each constituent tracker becomes an expert of a certain appearance. During tracking, the proposed algorithm combines only the appearance-aware relevant experts to produce boosted tracking decisions. Additionally, we propose a versatile spatial windowing technique to enhance the individual expert trackers. For this purpose, spatial windows are learned for target objects as well as the correlation filters and then the windowed regions are processed for more robust correlations. In our extensive experiments on benchmark datasets, we achieve a substantial performance increase by using the proposed tracking algorithm together with the spatial windowing.

HCP track calculations in Lif:Mg,Ti: 3D modeling of the ''track – escape'' parameter

International Nuclear Information System (INIS)

Sattinger, D.; Sharon, A.; Horowitz, Y.S.

2011-01-01

The conceptual framework of the track interaction model (TIM) was conceived in the 1970s and mathematically formulated in the 1980s to describe heavy charged particle TL fluence response supralinearity. The extended track interaction model (ETIM) was developed to include saturation effects due to overlapping tracks and has been applied to both proton and alpha particle TL fluence response. One of the parameters of major importance in the TIM is the ''track – escape'' parameter, defined by N e /N w , where N e represents the number of electrons which escape the parent track during heating, and N w is the number of electrons which recombine within the parent track to produce a TL photon. Recently a first attempt was carried out to theoretically model escape parameters calculated in 2D geometry as a function of particle type and energy using trapping center (TC), luminescent center (LC) and competitive center (CC) occupation probabilities calculated from track segment radial dose distributions and optical absorption (OA) dose response. In this study, the calculations are extended to 3D geometry using a Monte Carlo approach which samples the point of creation of the charge carriers according to the TC occupation probabilities and then estimates N w by sampling the chord length to the track exterior. Charge carriers which escape the irradiated track volume contribute to N e . This more sophisticated 3D calculation of N e /N w is expected to increase the reliability of the modeling of heavy charged particle TL fluence response in the framework of the ETIM and enhance our understanding of “track effects” in Heavy Charged Particle (HCP) induced TL.

Tracking studies towards EDM measurements at COSY

Energy Technology Data Exchange (ETDEWEB)

Rosenthal, Marcel [Institut fuer Kernphysik, Forschungszentrum Juelich, Juelich (Germany); Physikalisches Institut III B, RWTH Aachen, Aachen (Germany)

2015-07-01

Electric Dipole Moments (EDMs) violate parity and time reversal symmetries. Therefore, direct measurements of charged particles' EDMs would be a strong hint for physics beyond the Standard Model. The JEDI collaboration investigates the feasibility of such measurements for protons, deuterons, and Helium3 in storage rings. Precursor studies are performed at the existing conventional Cooler Synchtrotron COSY in Juelich. A measurement time of about 1000 seconds is proposed. This requires a setup providing a long spin coherence time in the plane perpendicular to the invariant spin axis. During the measurement run, it is planned to use radiofrequency devices to create an EDM related signal. The contribution of imperfections, which could mimic such a signal, is explored in beam and spin dynamics simulations. The software framework COSY INFINITY is used to calculate transfer maps of the magnets and performs long term tracking studies. Recent efforts extend the code by the EDM contribution to spin motion and by the calculation of timedependent maps required for tracking in nonstatic fields. These enhancements are benchmarked with analytical predictions and with test measurements at COSY.

Pose Tracking Algorithm of an Endoscopic Surgery Robot Wrist

International Nuclear Information System (INIS)

Wang, L; Yin, H L; Meng, Q

2006-01-01

In recent two decades, more and more research on the endoscopic surgery has been carried out [2]. Most of the work focuses on the development of the robot in the field of robotics and the navigation of the surgery tools based on computer graphics. But the tracking and locating of the EndoWrist is also a very important aspect. This paper deals with the the tracking algorithm of the EndoWrist's pose (position and orientation). The linear tracking of the position is handled by the Kalman Filter. The quaternion-based nonlinear orientation tracking is implemented with the Extended Kalman Filter. The most innovative point of this paper is the parameterization of the motion model of the Extended Kalman Filter

Model-Based Motion Tracking of Infants

DEFF Research Database (Denmark)

Olsen, Mikkel Damgaard; Herskind, Anna; Nielsen, Jens Bo

2014-01-01

Even though motion tracking is a widely used technique to analyze and measure human movements, only a few studies focus on motion tracking of infants. In recent years, a number of studies have emerged focusing on analyzing the motion pattern of infants, using computer vision. Most of these studies...... are based on 2D images, but few are based on 3D information. In this paper, we present a model-based approach for tracking infants in 3D. The study extends a novel study on graph-based motion tracking of infants and we show that the extension improves the tracking results. A 3D model is constructed...

Diffusion tensor imaging fiber tracking with reliable tracking orientation and flexible step size☆

Science.gov (United States)

Yao, Xufeng; Wang, Manning; Chen, Xinrong; Nie, Shengdong; Li, Zhexu; Xu, Xiaoping; Zhang, Xuelong; Song, Zhijian

2013-01-01

We propose a method of reliable tracking orientation and flexible step size fiber tracking. A new directional strategy was defined to select one optimal tracking orientation from each directional set, which was based on the single-tensor model and the two-tensor model. The directional set of planar voxels contained three tracking directions: two from the two-tensor model and one from the single-tensor model. The directional set of linear voxels contained only one principal vector. In addition, a flexible step size, rather than fixable step sizes, was implemented to improve the accuracy of fiber tracking. We used two sets of human data to assess the performance of our method; one was from a healthy volunteer and the other from a patient with low-grade glioma. Results verified that our method was superior to the single-tensor Fiber Assignment by Continuous Tracking and the two-tensor eXtended Streamline Tractography for showing detailed images of fiber bundles. PMID:25206444

Pose Tracking Algorithm of an Endoscopic Surgery Robot Wrist

Energy Technology Data Exchange (ETDEWEB)

Wang, L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Yin, H L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Meng, Q [Shanghai University of Electric Power (China)

2006-10-15

In recent two decades, more and more research on the endoscopic surgery has been carried out [2]. Most of the work focuses on the development of the robot in the field of robotics and the navigation of the surgery tools based on computer graphics. But the tracking and locating of the EndoWrist is also a very important aspect. This paper deals with the the tracking algorithm of the EndoWrist's pose (position and orientation). The linear tracking of the position is handled by the Kalman Filter. The quaternion-based nonlinear orientation tracking is implemented with the Extended Kalman Filter. The most innovative point of this paper is the parameterization of the motion model of the Extended Kalman Filter.

Persistent Aerial Tracking

KAUST Repository

Mueller, Matthias

2016-04-13

In this thesis, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photo-realistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the rst evaluation of many state of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. We also present a simulator that can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV "in the field", as well as, generate synthetic but photo-realistic tracking datasets with free ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator will be made publicly available to the vision community to further research in the area of object tracking from UAVs. Additionally, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by \\'handing over the camera\\' from one UAV to another. We integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

SEISMIC BEHAVIOR OF STEEL MONORAIL BRIDGES UNDER TRAIN LOAD DURING STRONG EARTHQUAKES

OpenAIRE

KIM, C. W.; KAWATANI, M.; KANBARA, T.; NISHIMURA, N.

2013-01-01

This paper investigated dynamic responses of steel monorail bridges incorporating train-bridge interaction under strong earthquakes. Two types of steel monorail bridges were considered in the study: a conventional type with steel track-girder; an advanced type with composite track-girder and simplified lateral bracing system. During strong earthquakes, monorail train was assumed standing on the track-girder of monorail bridges. Observations through the analytical study showed that considering...

p- and n-induced U-fission tracks as possible error sources in the fission track dating of extraterrestric samples

International Nuclear Information System (INIS)

Thiel, K.

1975-01-01

Using the fission track dating method by means of uranium fission tracks in meteorites and moon samples (according to the successful Apollo and Luna missions), special problems arise, as the samples frequently have a very great age and were subjected to the inmediate effect of primary cosmic radiation. To determine the share of induced fission tracks, an extended 'cosmic ray' simulation experiment was carried out on the p-synchrocyclotron in CERN, Geneva; the performance and results of the test with the proton flux and U fission track measurements are dealt with in detail. (HK/LH) [de

The attribution of incentive salience to Pavlovian alcohol cues: a shift from goal-tracking to sign-tracking.

Science.gov (United States)

Srey, Chandra S; Maddux, Jean-Marie N; Chaudhri, Nadia

2015-01-01

Environmental stimuli that are reliably paired with alcohol may acquire incentive salience, a property that can operate in the use and abuse of alcohol. Here we investigated the incentive salience of Pavlovian alcohol cues using a preclinical animal model. Male, Long-Evans rats (Harlan) with unrestricted access to food and water were acclimated to drinking 15% ethanol (v/v) in their home-cages. Rats then received Pavlovian autoshaping training in which the 10 s presentation of a retractable lever served as the conditioned stimulus (CS) and 15% ethanol served as the unconditioned stimulus (US) (0.2 ml/CS; 12 CS presentations/session; 27 sessions). Next, in an operant test of conditioned reinforcement, nose pokes into an active aperture delivered presentations of the lever-CS, whereas nose pokes into an inactive aperture had no consequences. Across initial autoshaping sessions, goal-tracking behavior, as measured by entries into the fluid port where ethanol was delivered, developed rapidly. However, with extended training goal-tracking diminished, and sign-tracking responses, as measured by lever-CS activations, emerged. Control rats that received explicitly unpaired CS and US presentations did not show goal-tracking or sign-tracking responses. In the test for conditioned reinforcement, rats with CS-US pairings during autoshaping training made more active relative to inactive nose pokes, whereas rats in the unpaired control group did not. Moreover, active nose pokes were positively correlated with sign-tracking behavior during autoshaping. Extended training may produce a shift in the learned properties of Pavlovian alcohol cues, such that after initially predicting alcohol availability they acquire robust incentive salience.

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

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.

Fast-track knee arthroplasty – status and future challenges

DEFF Research Database (Denmark)

Kehlet, Henrik; Thienpont, Emmanuel

2013-01-01

Fast-track programs have been developed for different surgical procedures leading to higher patient satisfaction and lower morbidity. This concept has been extended to knee arthroplasty in recent years. The purpose of this narrative review was to discuss the different aspects of fast-track knee...... arthroplasty....

An Approach of Tracking Control for Chaotic Systems

Directory of Open Access Journals (Sweden)

Jin Xing

2016-01-01

Full Text Available Combining the ergodicity of chaos and the Jacobian matrix, we design a general tracking controller for continuous and discrete chaotic systems. The control scheme has the ability to track a bounded reference signal. We prove its globally asymptotic stability and extend it to generalized projective synchronization. Numerical simulations verify the effectiveness of the proposed scheme.

The attribution of incentive salience to Pavlovian alcohol cues: a shift from goal-tracking to sign-tracking

Directory of Open Access Journals (Sweden)

Chandra S. Srey

2015-03-01

Full Text Available Environmental stimuli that are reliably paired with alcohol may acquire incentive salience, a property that can operate in the use and abuse of alcohol. Here we investigated the incentive salience of Pavlovian alcohol cues using a preclinical animal model. Male, Long-Evans rats (Harlan with unrestricted access to food and water were acclimated to drinking 15% ethanol (v/v in their home-cages. Rats then received Pavlovian autoshaping training in which the 10 second presentation of a retractable lever served as the conditioned stimulus (CS and 15% ethanol served as the unconditioned stimulus (US (0.2 ml/CS; 12 CS presentations/session; 27 sessions. Next, in an operant test of conditioned reinforcement, nose pokes into an active aperture delivered presentations of the lever-CS, whereas nose pokes into an inactive aperture had no consequences. Across initial autoshaping sessions, goal-tracking behavior, as measured by entries into the fluid port where ethanol was delivered, developed rapidly. However, with extended training goal-tracking diminished, and sign-tracking responses, as measured by lever-CS activations, emerged. Control rats that received explicitly unpaired CS and US presentations did not show goal-tracking or sign-tracking responses. In the test for conditioned reinforcement, rats with CS-US pairings during autoshaping training made more active relative to inactive nose pokes, whereas rats in the unpaired control group did not. Moreover, active nose pokes were positively correlated with sign-tracking behavior during autoshaping. Extended training may produce a shift in the learned properties of Pavlovian alcohol cues, such that after initially predicting alcohol availability they acquire robust incentive salience.

Extended neural network-based scheme for real-time force tracking with magnetorheological dampers

DEFF Research Database (Denmark)

Weber, Felix; Bhowmik, Subrata; Høgsberg, Jan Becker

2014-01-01

This paper validates numerically and experimentally a new neural network-based real-time force tracking scheme for magnetorheological (MR) dampers on a five-storey shear frame with MR damper. The inverse model is trained with absolute values of measured velocity and force because the targeted...... the pre-yield to the post-yield region. A control-oriented approach is presented to compensate for these drawbacks. The resulting control force tracking scheme is validated for the emulation of viscous damping, clipped viscous damping with negative stiffness, and friction damping with negative stiffness...

Radiology film tracking in a distributed clinical network

International Nuclear Information System (INIS)

Marquette, D.D.; Arrildt, W.

1985-01-01

This paper describes a system for tracking radiology films designed and installed at the Johns Hopkins Hospital. The installation of database and network capabilities in a large hospital environment provide the opportunity to extend to all nursing units and clinics access to the hospital's film tracking system. Ethernet communication technology allows communication to remote libraries. The integration of film tracking with scheduling and order entry systems in radiology make it possible to attain a high level of automated database interface and film jacket label production

Alignment of the ALICE Inner Tracking System with cosmic-ray tracks

CERN Document Server

Aamodt, K; Abeysekara, U; Abrahantes Quintana, A; Adamová, D; Aggarwal, M M; Aglieri Rinella, G; Agocs, A G; Aguilar Salazar, S; Ahammed, Z; Ahmad, A; Ahmad, N; Ahn, S U; Akimoto, R; Akindinov, A; Aleksandrov, D; Alessandro, B; Alfaro Molina, R; Alici, A; Almaráz Aviña, E; Alme, J; Altini, V; Altinpinar, S; Alt, T; Andrei, C; Andronic, A; Anelli, G; Angelov, V; Anson, C; Anticic, T; Antinori, F; Antinori, S; Antipin, K; Antonczyk, D; Antonioli, P; Anzo, A; Aphecetche, L; Appelshäuser, H; Arcelli, S; Arceo, R; Arend, A; Armesto, N; Arnaldi, R; Aronsson, T; Arsene, I C; Asryan, A; Augustinus, A; Averbeck, R; Awes, T C; Äystö, J; Azmi, M D; Bablok, S; Bach, M; Badalà, A; Baek, Y W; Bagnasco, S; Bailhache, R; Bala, R; Baldisseri, A; Baldit, A; Bán, J; Barbera, R; Barile, F; Barnaföldi, G G; Barnby, L; Barret, V; Bartke, J; Basile, M; Basmanov, V; Bastid, N; Bathen, B; Batigne, G; Batyunya, B; Baumann, C; Bearden, I G; Becker, B; Belikov, I; Bellwied, R; Belmont-Moreno, E; Belogianni, A; Benhabib, L; Beolé, S; Berceanu, I; Bercuci, A; Berdermann, E; Berdnikov, Y; Betev, L; Bhasin, A; Bhati, A K; Bianchi, L; Bianchin, C; Bianchi, N; Bielcík, J; Bielcíková, J; Bilandzic, A; Bimbot, L; Biolcati, E; Blanc, A; Blanco, F; Blanco, F; Blau, D; Blume, C; Boccioli, M; Bock, N; Bogdanov, A; Bøggild, H; Bogolyubsky, M; Bohm, J; Boldizsár, L; Bombara, M; Bombonati, C; Bondila, M; Borel, H; Borshchov, V; Bortolin, C; Bose, S; Bosisio, L; Bossú, F; Botje, M; Böttger, S; Bourdaud, G; Boyer, B; Braun, M; Braun-Munzinger, P; Bravina, L; Bregant, M; Breitner, T; Bruckner, G; Bruna, E; Bruno, G E; Brun, R; Budnikov, D; Buesching, H; Bugaev, K; Buncic, P; Busch, O; Buthelezi, Z; Caffarri, D; Caines, H; Cai, X; Camacho, E; Camerini, P; Campbell, M; Canoa Roman, V; Capitani, G P; Cara Romeo, G; Carena, F; Carena, W; Carminati, F; Casanova Díaz, A; Caselle, M; Castillo Castellanos, J; Castillo Hernandez, J F; Catanescu, V; Cattaruzza, E; Cavicchioli, C; Cerello, P; Chambert, V; Chang, B; Chapeland, S; Charpy, A; Charvet, J L; Chattopadhyay, S; Chattopadhyay, S; Cherney, M; Cheshkov, C; Cheynis, B; Chiavassa, E; Chibante Barroso, V; Chinellato, D D; Chochula, P; Choi, K; Chojnacki, M; Christakoglou, P; Christensen, C H; Christiansen, P; Chujo, T; Chuman, F; Cicalo, C; Cifarelli, L; Cindolo, F; Cleymans, J; Cobanoglu, O; Coffin, J P; Coli, S; Colla, A; Conesa Balbastre, G; Conesa del Valle, Z; Conner, E S; Constantin, P; Contin, G; Contreras, J G; Cormier, T M; Corrales Morales, Y; Cortese, P; Cortés Maldonado, I; Cosentino, M R; Costa, F; Cotallo, M E; Crescio, E; Crochet, P; Cuautle, E; Cunqueiro, L; Cussonneau, J; Dainese, A; Dalsgaard, H H; Danu, A; Dash, A; Dash, S; Das, I; Das, S; de Barros, G O V; De Caro, A; de Cataldo, G; de Cuveland, J; De Falco, A; De Gaspari, M; de Groot, J; De Gruttola, D; de Haas, A P; De Marco, N; De Pasquale, S; De Remigis, R; de Rooij, R; de Vaux, G; Delagrange, H; Dellacasa, G; Deloff, A; Demanov, V; Dénes, E; Deppman, A; D'Erasmo, G; Derkach, D; Devaux, A; Di Bari, D; Di Giglio, C; Di Liberto, S; Di Mauro, A; Di Nezza, P; Dialinas, M; Díaz, L; Díaz, R; Dietel, T; Ding, H; Divià, R; Djuvsland, Ø; do Amaral Valdiviesso, G; Dobretsov, V; Dobrin, A; Dobrowolski, T; Dönigus, B; Domínguez, I; Dordic, O; Dubey, A K; Dubuisson, J; Ducroux, L; Dupieux, P; Dutta Majumdar, A K; Dutta Majumdar, M R; Elia, D; Emschermann, D; Enokizono, A; Espagnon, B; Estienne, M; Evans, D; Evrard, S; Eyyubova, G; Fabjan, C W; Fabris, D; Faivre, J; Falchieri, D; Fantoni, A; Fasel, M; Fearick, R; Fedunov, A; Fehlker, D; Fekete, V; Felea, D; Fenton-Olsen, B; Feofilov, G; Fernández Téllez, A; Ferreiro, E G; Ferretti, A; Ferretti, R; Figueredo, M A S; Filchagin, S; Fini, R; Fionda, F M; Fiore, E M; Floris, M; Fodor, Z; Foertsch, S; Foka, P; Fokin, S; Formenti, F; Fragiacomo, E; Fragkiadakis, M; Frankenfeld, U; Frolov, A; Fuchs, U; Furano, F; Furget, C; Fusco Girard, M; Gaardhøje, J J; Gadrat, S; Gagliardi, M; Gago, A; Gallio, M; Ganoti, P; Ganti, M S; Garabatos, C; García Trapaga, C; Gebelein, J; Gemme, R; Germain, M; Gheata, A; Gheata, M; Ghidini, B; Ghosh, P; Giraudo, G; Giubellino, P; Gladysz-Dziadus, E; Glasow, R; Glässel, P; Glenn, A; Gomez, R; González Santos, H; González-Trueba, L H; González-Zamora, P; Gorbunov, S; Gorbunov, Y; Gotovac, S; Gottschlag, H; Grabski, V; Grajcarek, R; Grelli, A; Grigoras, A; Grigoras, C; Grigoriev, V; Grigoryan, A; Grinyov, B; Grion, N; Gros, P; Grosse-Oetringhaus, J F; Grossiord, J Y; Grosso, R; Guarnaccia, C; Guber, F; Guernane, R; Guerzoni, B; Gulbrandsen, K; Gulkanyan, H; Gunji, T; Gupta, A; Gupta, R; Gustafsson, H A; Gutbrod, H; Haaland, Ø; Hadjidakis, C; Haiduc, M; Hamagaki, H; Hamar, G; Hamblen, J; Han, B H; Harris, J W; Hartig, M; Harutyunyan, A; Hasch, D; Hasegan, D; Hatzifotiadou, D; Hayrapetyan, A; Heide, M; Heinz, M; Helstrup, H; Herghelegiu, A; Hernández, C; Herrera Corral, G; Herrmann, N; Hetland, K F; Hicks, B; Hiei, A; Hille, P T; Hippolyte, B; Horaguchi, T; Hori, Y; Hristov, P; Hrivnácová, I; Huber, S; Humanic, T J; Hu, S; Hutter, D; Hwang, D S; Ichou, R; Ilkaev, R; Ilkiv, I; Innocenti, P G; Ippolitov, M; Irfan, M; Ivan, C; Ivanov, A; Ivanov, M; Ivanov, V; Iwasaki, T; Jachokowski, A; Jacobs, P; Jancurová, L; Jangal, S; Janik, R; Jayananda, K; Jena, C; Jena, S; Jirden, L; Jones, G T; Jones, P G; Jovanovic, P; Jung, H; Jung, W; Jusko, A; Kaidalov, A B; Kalcher, S; Kalinák, P; Kalliokoski, T; Kalweit, A; Kamal, A; Kamermans, R; Kanaki, K; Kang, E; Kang, J H; Kapitan, J; Kaplin, V; Kapusta, S; Karavicheva, T; Karpechev, E; Kazantsev, A; Kebschull, U; Keidel, R; Khan, M M; Khan, S A; Khanzadeev, A; Kharlov, Y; Kikola, D; Kileng, B; Kim, D J; Kim, D S; Kim, D W; Kim, H N; Kim, J H; Kim, J; Kim, J S; Kim, M; Kim, M; Kim, S H; Kim, S; Kim, Y; Kirsch, S; Kiselev, S; Kisel, I; Kisiel, A; Klay, J L; Klein-Bösing, C; Klein, J; Kliemant, M; Klovning, A; Kluge, A; Kniege, S; Koch, K; Kolevatov, R; Kolojvari, A; Kondratiev, V; Kondratyeva, N; Konevskih, A; Kornas, E; Kour, R; Kowalski, M; Kox, S; Kozlov, K; Králik, I; Kral, J; Kramer, F; Kraus, I; Kravcáková, A; Krawutschke, T; Krivda, M; Krumbhorn, D; Krus, M; Kryshen, E; Krzewicki, M; Kucheriaev, Y; Kuhn, C; Kuijer, P G; Kumar, L; Kumar, N; Kupczak, R; Kurashvili, P; Kurepin, A; Kurepin, A N; Kuryakin, A; Kushpil, S; Kushpil, V; Kutouski, M; Kvaerno, H; Kweon, M J; Kwon, Y; Lackner, F; Ladrón de Guevara, P; Lafage, V; Lal, C; Lara, C; La Rocca, P; Larsen, D T; Laurenti, G; Lazzeroni, C; Le Bornec, Y; Le Bris, N; Lee, H; Lee, K S; Lee, S C; Lefèvre, F; Lehnert, J; Leistam, L; Lenhardt, M; Lenti, V; León, H; León Monzón, I; León Vargas, H; Lévai, P; Lietava, R; Lindal, S; Lindenstruth, V; Lippmann, C; Lisa, M A; Listratenko, O; Liu, L; Li, Y; Loginov, V; Lohn, S; López Noriega, M; López-Ramírez, R; López Torres, E; Lopez, X; Løvhøiden, G; Lozea Feijo Soares, A; Lunardon, M; Luparello, G; Luquin, L; Lu, S; Lutz, J R; Luvisetto, M; Madagodahettige-Don, D M; Maevskaya, A; Mager, M; Mahajan, A; Mahapatra, D P; Maire, A; Makhlyueva, I; Ma, K; Malaev, M; Maldonado Cervantes, I; Malek, M; Mal'Kevich, D; Malkiewicz, T; Malzacher, P; Mamonov, A; Manceau, L; Mangotra, L; Manko, V; Manso, F; Manzari, V; Mao, Y; Mares, J; Margagliotti, G V; Margotti, A; Marín, A; Martashvili, I; Martinengo, P; Martínez Davalos, A; Martínez García, G; Martínez, M I; Maruyama, Y; Ma, R; Marzari Chiesa, A; Masciocchi, S; Masera, M; Masetti, M; Masoni, A; Massacrier, L; Mastromarco, M; Mastroserio, A; Matthews, Z L; Mattos Tavares, B; Matyja, A; Mayani, D; Mazza, G; Mazzoni, M A; Meddi, F; Menchaca-Rocha, A; Mendez Lorenzo, P; Meoni, M; Mercado Pérez, J; Mereu, P; Miake, Y; Michalon, A; Miftakhov, N; Milosevic, J; Minafra, F; Mischke, A; Miskowiec, D; Mitu, C; Mizoguchi, K; Mlynarz, J; Mohanty, B; Molnar, L; Mondal, M M; Montaño Zetina, L; Monteno, M; Montes, E; Morando, M; Moretto, S; Morsch, A; Moukhanova, T; Muccifora, V; Mudnic, E; Muhuri, S; Müller, H; Munhoz, M G; Munoz, J; Musa, L; Musso, A; Nandi, B K; Nania, R; Nappi, E; Navach, F; Navin, S; Nayak, T K; Nazarenko, S; Nazarov, G; Nedosekin, A; Nendaz, F; Newby, J; Nianine, A; Nicassio, M; Nielsen, B S; Nikolaev, S; Nikolic, V; Nikulin, S; Nikulin, V; Nilsen, B S; Nilsson, M S; Noferini, F; Nomokonov, P; Nooren, G; Novitzky, N; Nyatha, A; Nygaard, C; Nyiri, A; Nystrand, J; Ochirov, A; Odyniec, G; Oeschler, H; Oinonen, M; Okada, K; Okada, Y; Oldenburg, M; Oleniacz, J; Oppedisano, C; Orsini, F; Ortíz Velázquez, A; Ortona, G; Oskamp, C; Oskarsson, A; Osmic, F; Österman, L; Ostrowski, P; Otterlund, I; Otwinowski, J; Øvrebekk, G; Oyama, K; Ozawa, K; Pachmayer, Y; Pachr, M; Padilla, F; Pagano, P; Paic, G; Painke, F; Pajares, C; Palaha, A; Palmeri, A; Pal, S K; Pal, S; Panse, R; Pappalardo, G S; Park, W J; Pastircák, B; Pastore, C; Paticchio, V; Pavlinov, A; Pawlak, T; Peitzmann, T; Pepato, A; Pereira, H; Peressounko, D; Pérez, C; Perini, D; Perrino, D; Peryt, W; Peschek, J; Pesci, A; Peskov, V; Pestov, Y; Peters, A J; Petrácek, V; Petridis, A; Petris, M; Petrovici, M; Petrov, P; Petta, C; Peyré, J; Piano, S; Piccotti, A; Pikna, M; Pillot, P; Pinsky, L; Pitz, N; Piuz, F; Platt, R; Pluta, J; Pocheptsov, T; Pochybova, S; Podesta Lerma, P L M; Poggio, F; Poghosyan, M G; Poghosyan, T; Polák, K; Polichtchouk, B; Polozov, P; Polyakov, V; Pommeresch, B; Pop, A; Posa, F; Poskon, M; Pospisil, V; Potukuchi, B; Pouthas, J; Prasad, S K; Preghenella, R; Prino, F; Pruneau, C A; Pshenichnov, I; Puddu, G; Pujahari, P; Pulvirenti, A; Punin, A; Punin, V; Putis, M; Putschke, J; Quercigh, E; Rachevski, A; Rademakers, A; Radomski, S; Räihä, T S; Rak, J; Rakotozafindrabe, A; Ramello, L; Ramírez Reyes, A; Rammler, M; Raniwala, R; Raniwala, S; Räsänen, S; Rashevskaya, I; Rath, S; Read, K F; Real, J; Redlich, K; Renfordt, R; Reolon, A R; Reshetin, A; Rettig, F; Revol, J P; Reygers, K; Ricaud, H; Riccati, L; Ricci, R A; Richter, M; Riedler, P; Riegler, W; Riggi, F; Rivetti, A; Rodriguez Cahuantzi, M; Røed, K; Röhrich, D; Román López, S; Romita, R; Ronchetti, F; Rosinský, P; Rosnet, P; Rossegger, S; Rossi, A; Roukoutakis, F; Rousseau, S; Roy, C; Roy, P; Rubio-Montero, A J; Rui, R; Rusanov, I; Russo, G; Ryabinkin, E; Rybicki, A; Sadovsky, S; Safarík, K; Sahoo, R; Saini, J; Saiz, P; Sakata, D; Salgado, C A; Salgueiro Dominques da Silva, R; Salur, S; Samanta, T; Sambyal, S; Samsonov, V; Sándor, L; Sandoval, A; Sano, M; Sano, S; Santo, R; Santoro, R; Sarkamo, J; Saturnini, P; Scapparone, E; Scarlassara, F; Scharenberg, R P; Schiaua, C; Schicker, R; Schindler, H; Schmidt, C; Schmidt, H R; Schossmaier, K; Schreiner, S; Schuchmann, S; Schukraft, J; Schutz, Y; Schwarz, K; Schweda, K; Scioli, G; Scomparin, E; Segato, G; Semenov, D; Senyukov, S; Seo, J; Serci, S; Serkin, L; Serradilla, E; Sevcenco, A; Sgura, I; Shabratova, G; Shahoyan, R; Sharkov, G; Sharma, N; Sharma, S; Shigaki, K; Shimomura, M; Shtejer, K; Sibiriak, Y; Siciliano, M; Sicking, E; Siddi, E; Siemiarczuk, T; Silenzi, A; Silvermyr, D; Simili, E; Simonetti, G; Singaraju, R; Singhal, V; Singh, R; Sinha, B C; Sinha, T; Sitar, B; Sitta, M; Skaali, T B; Skjerdal, K; Smakal, R; Smirnov, N; Snellings, R; Snow, H; Søgaard, C; Sokolov, O; Soloviev, A; Soltveit, H K; Soltz, R; Sommer, W; Son, C W; Song, M; Son, H S; Soos, C; Soramel, F; Soyk, D; Spyropoulou-Stassinaki, M; Srivastava, B K; Stachel, J; Staley, F; Stan, I; Stefanek, G; Stefanini, G; Steinbeck, T; Stenlund, E; Steyn, G; Stocco, D; Stock, R; Stolpovsky, P; Strmen, P; Suaide, A A P; Subieta Vásquez, M A; Sugitate, T; Suire, C; Sumbera, M; Susa, T; Swoboda, D; Symons, J; Szanto de Toledo, A; Szarka, I; Szostak, A; Szuba, M; Tadel, M; Tagridis, C; Takahara, A; Takahashi, J; Tanabe, R; Tapia Takaki, J D; Taureg, H; Tauro, A; Tavlet, M; Tejeda Muñoz, G; Telesca, A; Terrevoli, C; Thäder, J; Tieulent, R; Tlusty, D; Toia, A; Tolyhy, T; Torcato de Matos, C; Torii, H; Torralba, G; Toscano, L; Tosello, F; Tournaire, A; Traczyk, T; Tribedy, P; Tröger, G; Truesdale, D; Trzaska, W H; Tsiledakis, G; Tsilis, E; Tsuji, T; Tumkin, A; Turrisi, R; Turvey, A; Tveter, T S; Tydesjö, H; Tywoniuk, K; Ulery, J; Ullaland, K; Uras, A; Urbán, J; Urciuoli, G M; Usai, G L; Vacchi, A; Vala, M; Valencia Palomo, L; Vallero, S; van den Brink, A; van der Kolk, N; Vande Vyvre, P; van Leeuwen, M; Vannucci, L; Vargas, A; Varma, R; Vasiliev, A; Vassiliev, I; Vassiliou, M; Vechernin, V; Venaruzzo, M; Vercellin, E; Vergara, S; Vernet, R; Verweij, M; Vetlitskiy, I; Vickovic, L; Viesti, G; Vikhlyantsev, O; Vilakazi, Z; Villalobos Baillie, O; Vinogradov, A; Vinogradov, L; Vinogradov, Y; Virgili, T; Viyogi, Y P; Vodopianov, A; Voloshin, K; Voloshin, S; Volpe, G; von Haller, B; Vranic, D; Vrláková, J; Vulpescu, B; Wagner, B; Wagner, V; Wallet, L; Wan, R; Wang, D; Wang, Y; Watanabe, K; Wen, Q; Wessels, J; Wiechula, J; Wikne, J; Wilk, A; Wilk, G; Williams, M C S; Willis, N; Windelband, B; Xu, C; Yang, C; Yang, H; Yasnopolsky, A; Yermia, F; Yi, J; Yin, Z; Yokoyama, H; Yoo, I-K; Yuan, X; Yushmanov, I; Zabrodin, E; Zagreev, B; Zalite, A; Zampolli, C; Zanevsky, Yu; Zaporozhets, Y; Zarochentsev, A; Závada, P; Zbroszczyk, H; Zelnicek, P; Zenin, A; Zepeda, A; Zgura, I; Zhalov, M; Zhang, X; Zhou, D; Zhou, S; Zhu, J; Zichichi, A; Zinchenko, A; Zinovjev, G; Zinovjev, M; Zoccarato, Y; Zychácek, V

2010-01-01

ALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with three different technologies; in the outward direction: two layers of pixel detectors, two layers each of drift, and strip detectors. The number of parameters to be determined in the spatial alignment of the 2198 sensor modules of the ITS is about 13,000. The target alignment precision is well below 10 micron in some cases (pixels). The sources of alignment information include survey measurements, and the reconstructed tracks from cosmic rays and from proton-proton collisions. The main track-based alignment method uses the Millepede global approach. An iterative local method was developed and used as well. We present the results obtained for the ITS alignment using about 10^5 charged tracks from cosmic rays that h...

Tracking planets and moons: mechanisms of object tracking revealed with a new paradigm.

Science.gov (United States)

Tombu, Michael; Seiffert, Adriane E

2011-04-01

People can attend to and track multiple moving objects over time. Cognitive theories of this ability emphasize location information and differ on the importance of motion information. Results from several experiments have shown that increasing object speed impairs performance, although speed was confounded with other properties such as proximity of objects to one another. Here, we introduce a new paradigm to study multiple object tracking in which object speed and object proximity were manipulated independently. Like the motion of a planet and moon, each target-distractor pair rotated about both a common local point as well as the center of the screen. Tracking performance was strongly affected by object speed even when proximity was controlled. Additional results suggest that two different mechanisms are used in object tracking--one sensitive to speed and proximity and the other sensitive to the number of distractors. These observations support models of object tracking that include information about object motion and reject models that use location alone.

Tracking of overweight from mid-adolescence into adulthood

DEFF Research Database (Denmark)

Rasmussen, Mette; Holstein, Bjørn E; Due, Pernille

2012-01-01

Socially differentiated tracking of health and health behaviours may contribute to health inequalities in adulthood. The modifying effect of socio-economic position on the tracking of overweight from mid-adolescence (age 15 years) into adulthood (age 27 years) was assessed in a randomly sampled D...... Danish cohort (n = 561). The tracking was studied by prediction analyses conducted by logistic regression analyses. Strong tracking patterns were found to be independent of socio-economic background....

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

Bayesian target tracking based on particle filter

Institute of Scientific and Technical Information of China (English)

无

2005-01-01

For being able to deal with the nonlinear or non-Gaussian problems, particle filters have been studied by many researchers. Based on particle filter, the extended Kalman filter (EKF) proposal function is applied to Bayesian target tracking. Markov chain Monte Carlo (MCMC) method, the resampling step, etc novel techniques are also introduced into Bayesian target tracking. And the simulation results confirm the improved particle filter with these techniques outperforms the basic one.

An adaptive compensation algorithm for temperature drift of micro-electro-mechanical systems gyroscopes using a strong tracking Kalman filter.

Science.gov (United States)

Feng, Yibo; Li, Xisheng; Zhang, Xiaojuan

2015-05-13

We present an adaptive algorithm for a system integrated with micro-electro-mechanical systems (MEMS) gyroscopes and a compass to eliminate the influence from the environment, compensate the temperature drift precisely, and improve the accuracy of the MEMS gyroscope. We use a simplified drift model and changing but appropriate model parameters to implement this algorithm. The model of MEMS gyroscope temperature drift is constructed mostly on the basis of the temperature sensitivity of the gyroscope. As the state variables of a strong tracking Kalman filter (STKF), the parameters of the temperature drift model can be calculated to adapt to the environment under the support of the compass. These parameters change intelligently with the environment to maintain the precision of the MEMS gyroscope in the changing temperature. The heading error is less than 0.6° in the static temperature experiment, and also is kept in the range from 5° to -2° in the dynamic outdoor experiment. This demonstrates that the proposed algorithm exhibits strong adaptability to a changing temperature, and performs significantly better than KF and MLR to compensate the temperature drift of a gyroscope and eliminate the influence of temperature variation.

An Adaptive Compensation Algorithm for Temperature Drift of Micro-Electro-Mechanical Systems Gyroscopes Using a Strong Tracking Kalman Filter

Directory of Open Access Journals (Sweden)

Yibo Feng

2015-05-01

Full Text Available We present an adaptive algorithm for a system integrated with micro-electro-mechanical systems (MEMS gyroscopes and a compass to eliminate the influence from the environment, compensate the temperature drift precisely, and improve the accuracy of the MEMS gyroscope. We use a simplified drift model and changing but appropriate model parameters to implement this algorithm. The model of MEMS gyroscope temperature drift is constructed mostly on the basis of the temperature sensitivity of the gyroscope. As the state variables of a strong tracking Kalman filter (STKF, the parameters of the temperature drift model can be calculated to adapt to the environment under the support of the compass. These parameters change intelligently with the environment to maintain the precision of the MEMS gyroscope in the changing temperature. The heading error is less than 0.6° in the static temperature experiment, and also is kept in the range from 5° to −2° in the dynamic outdoor experiment. This demonstrates that the proposed algorithm exhibits strong adaptability to a changing temperature, and performs significantly better than KF and MLR to compensate the temperature drift of a gyroscope and eliminate the influence of temperature variation.

Theoretical aspects of the formation and evolution of charged particle tracks

CERN Document Server

Miterev, A M

2002-01-01

Theoretical ideas on the formation and evolution of charged particle tracks in a condensed medium are discussed. The historical development of the field is briefly reviewed. The distribution of charged particle energies on quantum states and the volume of the absorbing medium are considered. and conditions for the formation of various track structures are discussed. The structures of extended heavy-ion tracks are compared for some ion parameters and track characteristics take to be the same. Relaxation processes in the tracks of multicharged ions ate analyzed. Track effects ate considered and possible mechanisms for the formation of chemically active defects in a latent track are described

Alignment of the ALICE Inner Tracking System with cosmic-ray tracks

NARCIS (Netherlands)

Aamodt, K.; Chojnacki, M.; Christakoglou, P.; de Haas, A.P.; de Rooij, R. S.; Grelli, A.|info:eu-repo/dai/nl/326052577; Ivan, C.G.|info:eu-repo/dai/nl/304847747; Kamermans, R.|info:eu-repo/dai/nl/073698733; Mischke, A.|info:eu-repo/dai/nl/325781435; Nooren, G.J.L.|info:eu-repo/dai/nl/07051349X; Oskamp, C.J.; Peitzmann, T.|info:eu-repo/dai/nl/304833959; Simili, E.; van den Brink, A.; van Leeuwen, M.|info:eu-repo/dai/nl/250599171; Verweij, M.|info:eu-repo/dai/nl/330542133

2010-01-01

ALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with

A Benchmark and Simulator for UAV Tracking

KAUST Repository

Mueller, Matthias; Smith, Neil; Ghanem, Bernard

2016-01-01

In this paper, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photorealistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the first evaluation of many state-of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. The simulator can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV “in the field”, as well as, generate synthetic but photo-realistic tracking datasets with automatic ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator are made publicly available to the vision community on our website to further research in the area of object tracking from UAVs. (https://ivul.kaust.edu.sa/Pages/pub-benchmark-simulator-uav.aspx.). © Springer International Publishing AG 2016.

A Benchmark and Simulator for UAV Tracking

KAUST Repository

Mueller, Matthias

2016-09-16

In this paper, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photorealistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the first evaluation of many state-of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. The simulator can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV “in the field”, as well as, generate synthetic but photo-realistic tracking datasets with automatic ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator are made publicly available to the vision community on our website to further research in the area of object tracking from UAVs. (https://ivul.kaust.edu.sa/Pages/pub-benchmark-simulator-uav.aspx.). © Springer International Publishing AG 2016.

A Novel Biped Pattern Generator Based on Extended ZMP and Extended Cart-Table Model

Directory of Open Access Journals (Sweden)

Guangbin Sun

2015-07-01

Full Text Available This paper focuses on planning patterns for biped walking on complex terrains. Two problems are solved: ZMP (zero moment point cannot be used on uneven terrain, and the conventional cart-table model does not allow vertical CM (centre of mass motion. For the ZMP definition problem, we propose the extended ZMP (EZMP concept as an extension of ZMP to uneven terrains. It can be used to judge dynamic balance on universal terrains. We achieve a deeper insight into the connection and difference between ZMP and EZMP by adding different constraints. For the model problem, we extend the cart-table model by using a dynamic constraint instead of constant height constraint, which results in a mathematically symmetric set of three equations. In this way, the vertical motion is enabled and the resultant equations are still linear. Based on the extended ZMP concept and extended cart-table model, a biped pattern generator using triple preview controllers is constructed and implemented simultaneously to three dimensions. Using the proposed pattern generator, the Atlas robot is simulated. The simulation results show the robot can walk stably on rather complex terrains by accurately tracking extended ZMP.

Tracking method of small receiver coil using MR scanner

International Nuclear Information System (INIS)

Onogi, Shinya; Liao, Hongen; Kobayashi, Etsuko; Sakuma, Ichiro; Watanabe, Sigeru

2007-01-01

MR guided surgery is quite effective in realizing accurate and safe minimally invasive surgery (MIS). The combination of intra-operative MRI, surgical navigation system, and surgical robot should be of practical use in the field of MIS in the future. When we use flexible endoscope type robotic manipulator, the position and the orientation of the tip point of the flexible forceps should be navigated and controlled by a robotic manipulator. However, the conventional position sensor can not be used because of the strong magnetic field and the limited workspace. We propose a novel tracking method named extended active tracking (EAT), which is based on the active tracking algorithm. EAT can measure the position and the orientation of the tracking coils synchronically. The principle of EAT is three points measurement by three series inductance. We can calculate the orientation of three coils using the measured 3-D positions of coils. In this paper, three experiments was conducted to evaluate the basic performance of the EAT. First experiment is the flip angle adjustment for the reduction of background noise, which is caused by the proton around each inductance. The experimental results shown that the inductance positions could be clearly observed without background noise at 6-deg flip angle with nuclear magnetic resonance (NMR) signal peaks. Second experiment is the reproducibility evaluation. The fluctuation of measurement position and orientation were less than 0.3 mm (SD) and 1.0 deg (SD) at various positions and orientations. And standard deviation of the distance between the inductances at various positions and orientations is less than resolution (0.78 mm). Third experiment is an accuracy evaluation. The position measurement accuracy was 0.39 mm (RMS) using an optical tracking device. The orientation measurement accuracy was 3.5 deg (RMS) when the tracking coil was rotated 30 degree. Evaluation result suggests that EAT is possible to be used inside a patient body

Recent advances in the GENFIT track fitting package

Energy Technology Data Exchange (ETDEWEB)

Bicker, Karl A. [CERN, Geneva (Switzerland); Hoeppner, Christian; Ketzer, Bernhard; Neubert, Sebastian; Paul, Stephan; Rauch, Johannes [Technische Universitaet Muenchen, Munich (Germany)

2012-07-01

The GENFIT software package provides a framework for track fitting. Due to the modular and generic structure, it is usable with arbitrary detector and field geometries. GENFIT is used in several collaborations (e.g. Belle II, COMPASS, FOPI, PANDA). GENFIT provides hit classes for common detector types and their information is used by GENFIT in their native coordinate system. Hits are collected in tracks, as are track representations. The track representation handles the extrapolation of the track through matter and fields. Multiple track representations can be fitted simultaneously. GENFIT has recently been equipped with several new features. Besides adding Smoothing, the standard Kalman fit algorithm has been extended by a Deterministic Annealing Filter (DAF), which can tag noise hits. An interface to the RAVE vertexing package has equipped GENFIT with the capability for vertex reconstruction and fitting. Results from simulation and real data are presented.

A fast ellipse extended target PHD filter using box-particle implementation

Science.gov (United States)

Zhang, Yongquan; Ji, Hongbing; Hu, Qi

2018-01-01

This paper presents a box-particle implementation of the ellipse extended target probability hypothesis density (ET-PHD) filter, called the ellipse extended target box particle PHD (EET-BP-PHD) filter, where the extended targets are described as a Poisson model developed by Gilholm et al. and the term "box" is here equivalent to the term "interval" used in interval analysis. The proposed EET-BP-PHD filter is capable of dynamically tracking multiple ellipse extended targets and estimating the target states and the number of targets, in the presence of clutter measurements, false alarms and missed detections. To derive the PHD recursion of the EET-BP-PHD filter, a suitable measurement likelihood is defined for a given partitioning cell, and the main implementation steps are presented along with the necessary box approximations and manipulations. The limitations and capabilities of the proposed EET-BP-PHD filter are illustrated by simulation examples. The simulation results show that a box-particle implementation of the ET-PHD filter can avoid the high number of particles and reduce computational burden, compared to a particle implementation of that for extended target tracking.

Simulation and track reconstruction for beam telescopes

CERN Document Server

Maqbool, Salman

2017-01-01

Beam telescopes are used for testing new detectors under development. Sensors are placed and a particle beam is passed through them. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, it’s predicted hits on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them don’t account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framew...

Simulation and Track Reconstruction for Beam Telescopes

CERN Document Server

Maqbool, Salman

2017-01-01

Beam telescopes are an important tool to test new detectors under development in a particle beam. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, its predicted position on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them do not account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framework along with the General Broken ...

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.

Simultaneous pattern recognition and track fitting by the Kalman filtering method

International Nuclear Information System (INIS)

Billoir, P.

1990-01-01

A progressive pattern recognition algorithm based on the Kalman filtering method has been tested. The algorithm starts from a small track segment or from a fitted track of a neighbouring detector, then extends the candidate tracks by adding measured points one by one. The fitted parameters and weight matrix of the candidate track are updated when adding a point, and give an increasing precision on prediction of the next point. Thus, pattern recognition and track fitting can be accomplished simultaneously. The method has been implemented and tested for track reconstruction for the vertex detector of the ZEUS experiment at DESY. Detailed procedures of the method and its performance are presented. Its flexibility is described as well. (orig.)

Extended Cann Model for Behavioral Modeling of Envelope Tracking Power Amplifiers

DEFF Research Database (Denmark)

Tafuri, Felice Francesco; Larsen, Torben

2013-01-01

This paper deals with behavioral modeling of power amplifiers (PAs) for envelope tracking (ET) applications. In such a scenario, the power supply modulation brings in several additional challenges for the system design and, similarly, it becomes more difficult to obtain an accurate and general PA...... by the ET operation. The model performance is tested modeling data-sets acquired from an ET test bench including a commercial RFMD PA and an envelope modulator designed using a commercial IC from TI....

Synthetic tracked aperture ultrasound imaging: design, simulation, and experimental evaluation.

Science.gov (United States)

Zhang, Haichong K; Cheng, Alexis; Bottenus, Nick; Guo, Xiaoyu; Trahey, Gregg E; Boctor, Emad M

2016-04-01

Ultrasonography is a widely used imaging modality to visualize anatomical structures due to its low cost and ease of use; however, it is challenging to acquire acceptable image quality in deep tissue. Synthetic aperture (SA) is a technique used to increase image resolution by synthesizing information from multiple subapertures, but the resolution improvement is limited by the physical size of the array transducer. With a large F-number, it is difficult to achieve high resolution in deep regions without extending the effective aperture size. We propose a method to extend the available aperture size for SA-called synthetic tracked aperture ultrasound (STRATUS) imaging-by sweeping an ultrasound transducer while tracking its orientation and location. Tracking information of the ultrasound probe is used to synthesize the signals received at different positions. Considering the practical implementation, we estimated the effect of tracking and ultrasound calibration error to the quality of the final beamformed image through simulation. In addition, to experimentally validate this approach, a 6 degree-of-freedom robot arm was used as a mechanical tracker to hold an ultrasound transducer and to apply in-plane lateral translational motion. Results indicate that STRATUS imaging with robotic tracking has the potential to improve ultrasound image quality.

Mobile Augmented Reality Support for Architects Based on Feature Tracking Techniques

DEFF Research Database (Denmark)

Bang Nielsen, Michael; Kramp, Gunnar; Grønbæk, Kaj

2004-01-01

on the horizon view from an office building, while working on a courtyard garden proposal. The SitePack applies a novel combination of GPS tracking and vision based feature tracking in its support for architects. The SitePack requires no preparation of the site and combines and extends the strengths of previous...

Extending Teach and Repeat to Pivoting Wheelchairs

Directory of Open Access Journals (Sweden)

Guillermo Del Castillo

2003-02-01

Full Text Available The paper extends the teach-and-repeat paradigm that has been successful for the control of holonomic robots to nonholonomic wheelchairs which may undergo pivoting action over the course of their taught movement. Due to the nonholonomic nature of the vehicle kinematics, estimation is required -- in the example given herein, based upon video detection of wall-mounted cues -- both in the teaching and the tracking events. In order to accommodate motion that approaches pivoting action as well as motion that approaches straight-line action, the estimation equations of the Extended Kalman Filter and the control equations are formulated using two different definitions of a nontemporal independent variable. The paper motivates the need for pivoting action in real-life settings by reporting extensively on the abilities and limitations of estimation-based teach-and-repeat action where pivoting and near-pivoting action is disallowed. Following formulation of the equations in the near-pivot mode, the paper reports upon experiments where taught trajectories which entail a seamless mix of near-straight and near-pivot action are tracked.

Amorphous track models: a numerical comparison study

DEFF Research Database (Denmark)

Greilich, Steffen; Grzanka, Leszek; Hahn, Ute

in carbon ion treatment at the particle facility HIT in Heidelberg. Apparent differences between the LEM and the Katz model are the way how interactions of individual particle tracks and how extended targets are handled. Complex scenarios, however, can mask the actual effect of these differences. Here, we......Amorphous track models such as Katz' Ion-Gamma-Kill (IGK) approach [1, 2] or the Local Effect Model (LEM) [3, 4] had reasonable success in predicting the response of solid state dosimeters and radiobiological systems. LEM is currently applied in radiotherapy for biological dose optimization...

Fission-track ages and their geological interpretation

International Nuclear Information System (INIS)

Wagner, G.A.

1981-01-01

In fission-track dating, experimental procedures such as etching and thermal pre-treatment may strongly affect the age values determined and their geological interpretation. This peculiarity is due to the common phenomenon of partial fading of fossil (spontaneous-) fission tracks during a sample's geological history. The proper geological interpretation of the age data must take into account the specific experimental conditions, the stability characteristics and size distribution of fission tracks in the sample, the ages of co-existing minerals, and the independent information about the thermal history of the geological region. (author)

Graph-based geometric-iconic guide-wire tracking.

Science.gov (United States)

Honnorat, Nicolas; Vaillant, Régis; Paragios, Nikos

2011-01-01

In this paper we introduce a novel hybrid graph-based approach for Guide-wire tracking. The image support is captured by steerable filters and improved through tensor voting. Then, a graphical model is considered that represents guide-wire extraction/tracking through a B-spline control-point model. Points with strong geometric interest (landmarks) are automatically determined and anchored to such a representation. Tracking is then performed through discrete MRFs that optimize the spatio-temporal positions of the control points while establishing landmark temporal correspondences. Promising results demonstrate the potentials of our method.

Ion track etching revisited: II. Electronic properties of aged tracks in polymers

Science.gov (United States)

Fink, D.; Muñoz Hernández, G.; Cruz, S. A.; Garcia-Arellano, H.; Vacik, J.; Hnatowicz, V.; Kiv, A.; Alfonta, L.

2018-02-01

We compile here electronic ion track etching effects, such as capacitive-type currents, current spike emission, phase shift, rectification and background currents that eventually emerge upon application of sinusoidal alternating voltages across thin, aged swift heavy ion-irradiated polymer foils during etching. Both capacitive-type currents and current spike emission occur as long as obstacles still prevent a smooth continuous charge carrier passage across the foils. In the case of sufficiently high applied electric fields, these obstacles are overcome by spike emission. These effects vanish upon etchant breakthrough. Subsequent transmitted currents are usually of Ohmic type, but shortly after breakthrough (during the track' core etching) often still exhibit deviations such as strong positive phase shifts. They stem from very slow charge carrier mobility across the etched ion tracks due to retarding trapping/detrapping processes. Upon etching the track's penumbra, one occasionally observes a split-up into two transmitted current components, one with positive and another one with negative phase shifts. Usually, these phase shifts vanish when bulk etching starts. Current rectification upon track etching is a very frequent phenomenon. Rectification uses to inverse when core etching ends and penumbra etching begins. When the latter ends, rectification largely vanishes. Occasionally, some residual rectification remains which we attribute to the aged polymeric bulk itself. Last not least, we still consider background currents which often emerge transiently during track etching. We could assign them clearly to differences in the electrochemical potential of the liquids on both sides of the etched polymer foils. Transient relaxation effects during the track etching cause their eventually chaotic behaviour.

Information structure and reference tracking in complex sentences

CERN Document Server

Gijn, Rik van; Matic, Dejan

2014-01-01

This paper discusses argument marking and reference tracking in Mekens complex clauses and their correlation to information structure. The distribution of pronominal arguments in Mekens simple clauses follows an absolutive pattern with main verbs. Complex clauses maintain the morphological absolutive argument marking, but show a nominative pattern with respect to argument reference tracking, since transitive and intransitive subjects function as syntactic pivots. The language extends the use of argument-marking verb morphology to control the reference of discourse participants across clauses.

The effect of track load correlation on ground-borne vibration from railways

Science.gov (United States)

Ntotsios, Evangelos; Thompson, David; Hussein, Mohammed

2017-08-01

In predictions of ground-borne vibration from railways, it is generally assumed that the unevenness profile of the wheel and rail is fully correlated between the two rails and the two wheels of an axle. This leads to identical contact forces at the two rails and can allow further simplifications of the vehicle model, the track model and the track/ground interface conditions. In the present paper, the level of correlation of the track loading at the wheel/rail interface due to rail unevenness and its influence on predictions of ground vibration is investigated. The extent to which the unevenness of the two rails is correlated has been estimated from measurements of track geometry obtained with track recording vehicles for four different tracks. It was found that for wavelengths longer than about 3 m the unevenness of the two rails can be considered to be strongly correlated and in phase. To investigate the effect of this on ground vibration, an existing model expressed in the wavenumber-frequency domain is extended to include separate inputs on the two rails. The track is modelled as an infinite invariant linear structure resting on an elastic stratified half-space. This is excited by the gravitational loading of a passing train and the irregularity of the contact surfaces between the wheels and the rails. The railway model is developed in this work to be versatile so that it can account or discard the effect of load correlations on the two rails beside the effects of variation of the tractions across the width of the track-ground interface and the vehicle sprung mass, as well as the roll motion of the sleepers and the axle. A comparative analysis is carried out on the influence of these factors on the response predictions using numerical simulations. It is shown that, when determining the vibration in the free field, it is important to include in the model the traction variation across the track-ground interface and the non-symmetrical loading at the two rails that

Track benchmarking method for uncertainty quantification of particle tracking velocimetry interpolations

International Nuclear Information System (INIS)

Schneiders, Jan F G; Sciacchitano, Andrea

2017-01-01

The track benchmarking method (TBM) is proposed for uncertainty quantification of particle tracking velocimetry (PTV) data mapped onto a regular grid. The method provides statistical uncertainty for a velocity time-series and can in addition be used to obtain instantaneous uncertainty at increased computational cost. Interpolation techniques are typically used to map velocity data from scattered PTV (e.g. tomographic PTV and Shake-the-Box) measurements onto a Cartesian grid. Recent examples of these techniques are the FlowFit and VIC+  methods. The TBM approach estimates the random uncertainty in dense velocity fields by performing the velocity interpolation using a subset of typically 95% of the particle tracks and by considering the remaining tracks as an independent benchmarking reference. In addition, also a bias introduced by the interpolation technique is identified. The numerical assessment shows that the approach is accurate when particle trajectories are measured over an extended number of snapshots, typically on the order of 10. When only short particle tracks are available, the TBM estimate overestimates the measurement error. A correction to TBM is proposed and assessed to compensate for this overestimation. The experimental assessment considers the case of a jet flow, processed both by tomographic PIV and by VIC+. The uncertainty obtained by TBM provides a quantitative evaluation of the measurement accuracy and precision and highlights the regions of high error by means of bias and random uncertainty maps. In this way, it is possible to quantify the uncertainty reduction achieved by advanced interpolation algorithms with respect to standard correlation-based tomographic PIV. The use of TBM for uncertainty quantification and comparison of different processing techniques is demonstrated. (paper)

Multiple hypothesis tracking for the cyber domain

Science.gov (United States)

Schwoegler, Stefan; Blackman, Sam; Holsopple, Jared; Hirsch, Michael J.

2011-09-01

This paper discusses how methods used for conventional multiple hypothesis tracking (MHT) can be extended to domain-agnostic tracking of entities from non-kinematic constraints such as those imposed by cyber attacks in a potentially dense false alarm background. MHT is widely recognized as the premier method to avoid corrupting tracks with spurious data in the kinematic domain but it has not been extensively applied to other problem domains. The traditional approach is to tightly couple track maintenance (prediction, gating, filtering, probabilistic pruning, and target confirmation) with hypothesis management (clustering, incompatibility maintenance, hypothesis formation, and Nassociation pruning). However, by separating the domain specific track maintenance portion from the domain agnostic hypothesis management piece, we can begin to apply the wealth of knowledge gained from ground and air tracking solutions to the cyber (and other) domains. These realizations led to the creation of Raytheon's Multiple Hypothesis Extensible Tracking Architecture (MHETA). In this paper, we showcase MHETA for the cyber domain, plugging in a well established method, CUBRC's INFormation Engine for Real-time Decision making, (INFERD), for the association portion of the MHT. The result is a CyberMHT. We demonstrate the power of MHETA-INFERD using simulated data. Using metrics from both the tracking and cyber domains, we show that while no tracker is perfect, by applying MHETA-INFERD, advanced nonkinematic tracks can be captured in an automated way, perform better than non-MHT approaches, and decrease analyst response time to cyber threats.

Rational extended thermodynamics

CERN Document Server

Müller, Ingo

1998-01-01

Ordinary thermodynamics provides reliable results when the thermodynamic fields are smooth, in the sense that there are no steep gradients and no rapid changes. In fluids and gases this is the domain of the equations of Navier-Stokes and Fourier. Extended thermodynamics becomes relevant for rapidly varying and strongly inhomogeneous processes. Thus the propagation of high­ frequency waves, and the shape of shock waves, and the regression of small-scale fluctuation are governed by extended thermodynamics. The field equations of ordinary thermodynamics are parabolic while extended thermodynamics is governed by hyperbolic systems. The main ingredients of extended thermodynamics are • field equations of balance type, • constitutive quantities depending on the present local state and • entropy as a concave function of the state variables. This set of assumptions leads to first order quasi-linear symmetric hyperbolic systems of field equations; it guarantees the well-posedness of initial value problems and f...

Patient exposure tracking: the IAEA smart card project.

Science.gov (United States)

Rehani, Madan M; Frush, Donald P

2011-09-01

The existing approach of radiation protection is largely based on the collective dose to the population with provisions for protection at an individual level through justification and optimisation. With the individual patient dose now exceeding the life-long occupational dose to a worker in a typical radiology practice, there is a need to establish approaches based on the protection of an individual patient. Radiation exposure tracking seems a way forward in this respect. Technological advances in recent years have provided opportunities for tracking to becoming a reality. The IAEA project on Smart Card/SmartRadTrack is described in this paper. The tracking is now a reality in a few dozen centres in many countries connected by picture archiving and communication systems, and there is hope that this will extend to cover other countries and continents.

Patient exposure tracking: The IAEA smart card project

International Nuclear Information System (INIS)

Rehani, M. M.; Frush, D. P.

2011-01-01

The existing approach of radiation protection is largely based on the collective dose to the population with provisions for protection at an individual level through justification and optimisation. With the individual patient dose now exceeding the life-long occupational dose to a worker in a typical radiology practice, there is a need to establish approaches based on the protection of an individual patient. Radiation exposure tracking seems a way forward in this respect. Technological advances in recent years have provided opportunities for tracking to becoming a reality. The IAEA project on Smart Card/SmartRadTrack is described in this paper. The tracking is now a reality in a few dozen centres in many countries connected by picture archiving and communication systems, and there is hope that this will extend to cover other countries and continents. (authors)

Hemifield effects in multiple identity tracking.

Directory of Open Access Journals (Sweden)

Charlotte Hudson

Full Text Available In everyday life, we often need to attentively track moving objects. A previous study has claimed that this tracking occurs independently in the left and right visual hemifields (Alvarez & Cavanagh, 2005, Psychological Science,16, 637-647. Specifically, it was shown that observers were much more accurate at tracking objects that were spread over both visual hemifields as opposed to when all were confined to a single visual hemifield. In that study, observers were not required to remember the identities of the objects. Conversely, in real life, there is seldom any benefit to tracking an object unless you can also recall its identity. It has been predicted that when observers are required to remember the identities of the tracked objects a bilateral advantage should no longer be observed (Oksama & Hyönä, 2008, Cognitive Psychology, 56, 237-283. We tested this prediction and found that a bilateral advantage still occurred, though it was not as strong as when observers were not required to remember the identities of the targets. Even in the later case we found that tracking was not completely independent in the two visual hemifields. We present a combined model of multiple object tracking and multiple identity tracking that can explain our data.

Opportune acquisition and tracking time for the fast-moving targets in a ground-based telescope

Science.gov (United States)

Chen, Juan; Wang, Jianli; Chen, Tao

2004-10-01

Acquisition is defined as identification for a fixed target in the related field of sight (FOS), while tracking means the sway of the telescope's axis of sight (AOS). The automatic acquisition and tracking is a process in which the operating way of the telescope should be switched from guiding to automatic tracking. There are some kinds of method to improve the acquisition and tracking ability for fast moving targets: to extend the acquisition and tracking FOS with memory and storage information of the sensor system; the multimode control to improve the dynamic property of the servo system; to choose an opportune time for acquisition and tracking; to select the control regulator parameter in every working states. If the processor of the CCD sensor can temporarily remember and save the information of the target before it moves out of the FOS, correspondingly, the FOS may be extended. The data forecast technology is used to store the target information. The automatic interception experiments are carried out to verify the control strategy.

Target tracking system based on preliminary and precise two-stage compound cameras

Science.gov (United States)

Shen, Yiyan; Hu, Ruolan; She, Jun; Luo, Yiming; Zhou, Jie

2018-02-01

Early detection of goals and high-precision of target tracking is two important performance indicators which need to be balanced in actual target search tracking system. This paper proposed a target tracking system with preliminary and precise two - stage compound. This system using a large field of view to achieve the target search. After the target was searched and confirmed, switch into a small field of view for two field of view target tracking. In this system, an appropriate filed switching strategy is the key to achieve tracking. At the same time, two groups PID parameters are add into the system to reduce tracking error. This combination way with preliminary and precise two-stage compound can extend the scope of the target and improve the target tracking accuracy and this method has practical value.

Efficient Sample Tracking With OpenLabFramework

DEFF Research Database (Denmark)

List, Markus; Schmidt, Steffen; Trojnar, Jakub

2014-01-01

of samples created and need to be replaced with state-of-the-art laboratory information management systems. Such systems have been developed in large numbers, but they are often limited to specific research domains and types of data. One domain so far neglected is the management of libraries of vector clones...... and genetically engineered cell lines. OpenLabFramework is a newly developed web-application for sample tracking, particularly laid out to fill this gap, but with an open architecture allowing it to be extended for other biological materials and functional data. Its sample tracking mechanism is fully customizable...

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.

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.

Intelligent Sun Tracking for a CPV Power Plant

International Nuclear Information System (INIS)

Maqsood, Ishtiaq; Emziane, Mahieddine

2010-01-01

The output of a solar panel is strongly dependent on the amount of perpendicular light flux falling on its surface, and a tracking system tries to parallel the vector area of the solar panel surface to the incident solar flux. We present a tracking technique based on a two-axis sun sensor which can be used to increase the power output from a number of CPV arrays connected together in a solar power plant. The outdoor testing procedure of the developed two-axis sun sensor is discussed. The detail of the algorithm used together with the related sun tracking equipment is also presented and discussed for the new two axes sun tracking system.

Studies for the ALICE Inner Tracking System Upgrade

CERN Document Server

AUTHOR|(CDS)2079168; Musa, Luciano

The ALICE experiment at the CERN LHC identifies D0 mesons via secondary-vertex reconstruction and topological cuts to reduce the corresponding combinatorial background in heavy-ion collisions. The D0 meson is produced promptly in initial, hard scatterings via the strong interaction or as feed-down from weakly decaying B hadrons. Within this thesis, a novel method for the separation of prompt and feed-down D0 mesons using cut variations was implemented and applied to data from p–Pb collisions at $\\sqrt(s_\\mathrm{NN})=5.02$ TeV. The effectiveness of the secondary-vertex reconstruction strongly depends on the performance and in particular the pointing resolution of the Inner Tracking System. The upgrade of the ALICE Inner Tracking System for the Long Shutdown 2 of the LHC in 2019/2020 will significantly improve its vertex-reconstruction and tracking capabilities. It will be equipped with Monolithic Active Pixel Sensors manufactured using the TowerJazz 180nm CMOS process on wafers with a high-resistivity epitax...

Building a Strong Foundation: Mentoring Programs for Novice Tenure-Track Librarians in Academic Libraries

Science.gov (United States)

Goodsett, Mandi; Walsh, Andrew

2015-01-01

Increasingly, new librarians graduate to face a world of changing technology and new ways of interacting with information. The anxiety of this shifting environment is compounded for tenure-track librarians who must also meet scholarship and instruction requirements that may be unfamiliar to them. One way that librarians can navigate the transition…

Autonomous Multicamera Tracking on Embedded Smart Cameras

Directory of Open Access Journals (Sweden)

Bischof Horst

2007-01-01

Full Text Available There is currently a strong trend towards the deployment of advanced computer vision methods on embedded systems. This deployment is very challenging since embedded platforms often provide limited resources such as computing performance, memory, and power. In this paper we present a multicamera tracking method on distributed, embedded smart cameras. Smart cameras combine video sensing, processing, and communication on a single embedded device which is equipped with a multiprocessor computation and communication infrastructure. Our multicamera tracking approach focuses on a fully decentralized handover procedure between adjacent cameras. The basic idea is to initiate a single tracking instance in the multicamera system for each object of interest. The tracker follows the supervised object over the camera network, migrating to the camera which observes the object. Thus, no central coordination is required resulting in an autonomous and scalable tracking approach. We have fully implemented this novel multicamera tracking approach on our embedded smart cameras. Tracking is achieved by the well-known CamShift algorithm; the handover procedure is realized using a mobile agent system available on the smart camera network. Our approach has been successfully evaluated on tracking persons at our campus.

Exploiting target amplitude information to improve multi-target tracking

Science.gov (United States)

Ehrman, Lisa M.; Blair, W. Dale

2006-05-01

Closely-spaced (but resolved) targets pose a challenge for measurement-to-track data association algorithms. Since the Mahalanobis distances between measurements collected on closely-spaced targets and tracks are similar, several elements of the corresponding kinematic measurement-to-track cost matrix are also similar. Lacking any other information on which to base assignments, it is not surprising that data association algorithms make mistakes. One ad hoc approach for mitigating this problem is to multiply the kinematic measurement-to-track likelihoods by amplitude likelihoods. However, this can actually be detrimental to the measurement-to-track association process. With that in mind, this paper pursues a rigorous treatment of the hypothesis probabilities for kinematic measurements and features. Three simple scenarios are used to demonstrate the impact of basing data association decisions on these hypothesis probabilities for Rayleigh, fixed-amplitude, and Rician targets. The first scenario assumes that the tracker carries two tracks but only one measurement is collected. This provides insight into more complex scenarios in which there are fewer measurements than tracks. The second scenario includes two measurements and one track. This extends naturally to the case with more measurements than tracks. Two measurements and two tracks are present in the third scenario, which provides insight into the performance of this method when the number of measurements equals the number of tracks. In all cases, basing data association decisions on the hypothesis probabilities leads to good results.

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.

Adjoint Inversion for Extended Earthquake Source Kinematics From Very Dense Strong Motion Data

Science.gov (United States)

Ampuero, J. P.; Somala, S.; Lapusta, N.

2010-12-01

Addressing key open questions about earthquake dynamics requires a radical improvement of the robustness and resolution of seismic observations of large earthquakes. Proposals for a new generation of earthquake observation systems include the deployment of “community seismic networks” of low-cost accelerometers in urban areas and the extraction of strong ground motions from high-rate optical images of the Earth's surface recorded by a large space telescope in geostationary orbit. Both systems could deliver strong motion data with a spatial density orders of magnitude higher than current seismic networks. In particular, a “space seismometer” could sample the seismic wave field at a spatio-temporal resolution of 100 m, 1 Hz over areas several 100 km wide with an amplitude resolution of few cm/s in ground velocity. The amount of data to process would be immensely larger than what current extended source inversion algorithms can handle, which hampers the quantitative assessment of the cost-benefit trade-offs that can guide the practical design of the proposed earthquake observation systems. We report here on the development of a scalable source imaging technique based on iterative adjoint inversion and its application to the proof-of-concept of a space seismometer. We generated synthetic ground motions for M7 earthquake rupture scenarios based on dynamic rupture simulations on a vertical strike-slip fault embedded in an elastic half-space. A range of scenarios include increasing levels of complexity and interesting features such as supershear rupture speed. The resulting ground shaking is then processed accordingly to what would be captured by an optical satellite. Based on the resulting data, we perform source inversion by an adjoint/time-reversal method. The gradient of a cost function quantifying the waveform misfit between data and synthetics is efficiently obtained by applying the time-reversed ground velocity residuals as surface force sources, back

Extending Strong Scaling of Quantum Monte Carlo to the Exascale

Science.gov (United States)

Shulenburger, Luke; Baczewski, Andrew; Luo, Ye; Romero, Nichols; Kent, Paul

Quantum Monte Carlo is one of the most accurate and most computationally expensive methods for solving the electronic structure problem. In spite of its significant computational expense, its massively parallel nature is ideally suited to petascale computers which have enabled a wide range of applications to relatively large molecular and extended systems. Exascale capabilities have the potential to enable the application of QMC to significantly larger systems, capturing much of the complexity of real materials such as defects and impurities. However, both memory and computational demands will require significant changes to current algorithms to realize this possibility. This talk will detail both the causes of the problem and potential solutions. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corp, a wholly owned subsidiary of Lockheed Martin Corp, for the US Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000.

Optical fiber reach extended FMCW radar for remote respiratory tracking

DEFF Research Database (Denmark)

Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

2017-01-01

Wireless monitoring of human vital signs such as breathing rate is a nonintrusive alternative to contemporary solutions relying on physical contact. To ease the installment, fiber optical transmission is used to extend the reach from the transmitter and receiver circuitry to the antenna subsystem....... In this paper, a frequency modulated carrier wave radar, operating at 25.7–26.6 GHz and utilizing optical fiber extension, was experimentally demonstrated to accurately recover the breathing rate of a human placed 1 m away from the radar antennas....

Centralized Cooperative Positioning and Tracking with Realistic Communications Constraints

DEFF Research Database (Denmark)

Mensing, Christian; Nielsen, Jimmy Jessen

2010-01-01

on the overall performance will be assessed. As we are considering a dynamic scenario, the cooperative positioning algorithms are based on extended Kalman filtering for position estimation and tracking. Simulation results for ultra-wideband based ranging information and WLAN based communications infrastructure...

Distributed Extended Kalman Filter for Position, Velocity, Time, Estimation in Satellite Navigation Receivers

Directory of Open Access Journals (Sweden)

O. Jakubov

2013-09-01

Full Text Available Common techniques for position-velocity-time estimation in satellite navigation, iterative least squares and the extended Kalman filter, involve matrix operations. The matrix inversion and inclusion of a matrix library pose requirements on a computational power and operating platform of the navigation processor. In this paper, we introduce a novel distributed algorithm suitable for implementation in simple parallel processing units each for a tracked satellite. Such a unit performs only scalar sum, subtraction, multiplication, and division. The algorithm can be efficiently implemented in hardware logic. Given the fast position-velocity-time estimator, frequent estimates can foster dynamic performance of a vector tracking receiver. The algorithm has been designed from a factor graph representing the extended Kalman filter by splitting vector nodes into scalar ones resulting in a cyclic graph with few iterations needed. Monte Carlo simulations have been conducted to investigate convergence and accuracy. Simulation case studies for a vector tracking architecture and experimental measurements with a real-time software receiver developed at CTU in Prague were conducted. The algorithm offers compromises in stability, accuracy, and complexity depending on the number of iterations. In scenarios with a large number of tracked satellites, it can outperform the traditional methods at low complexity.

Fiber extended ultra-wideband radar for breath tracking through 10 cm concrete

DEFF Research Database (Denmark)

Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

2016-01-01

This article presents an Ultra-Wideband (UWB) radar with a 20 km NZ-DSF extension on the transmitter side. The radar is based on telecom class signal generation, antennas, and a recording module operating at 20 Gsa/s. The radar is transmitting a pulse covering the frequencies from 3.4 to 9.9 GHz........ The radar system was able to track the breathing of a human through a 10 cm concrete obstacle. The frequency output was verified through the use of a metal pendulum with a fixed oscillation period...

Fiber extended ultra-wideband radar for breath tracking through 10 cm concrete

DEFF Research Database (Denmark)

Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

2016-01-01

This article presents an Ultra-Wideband (UWB) radar with a 20 km NZ-DSF extension on the transmitter side. The radar is based on telecom class signal generation, antennas, and a recording module operating at 20 Gsa/s. The radar is transmitting a pulse covering the frequencies from 3.4 to 9.9 GHz....... The radar system was able to track the breathing of a human through a 10 cm concrete obstacle. The frequency output was verified through the use of a metal pendulum with a fixed oscillation period...

Hierarchically Coordinated Power Management for Target Tracking in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Feng Juan

2013-10-01

Full Text Available Energy efficiency is very important for wireless sensor networks (WSNs since sensor nodes have a limited energy supply from a battery. So far, a lot research has focused on this issue, while less emphasis has been placed on the adaptive sleep time for each node with a consideration for the application constraints. In this paper, we propose a hierarchically coordinated power management (HCPM approach, which both addresses the energy conservation problem and reduces the packet forwarding delay for target tracking WSNs based on a virtual-grid-based network structure. We extend the network lifetime by adopting an adaptive sleep scheduling scheme that combines the local power management (PM and the adaptive coordinate PM strategies to schedule the activities of the sensor nodes at the surveillance stage. Furthermore, we propose a hierarchical structure for the tracking stage. Experimental results show that the proposed approach has a greater capability of extending the network lifetime while maintaining a short transmission delay when compared with the protocol which does not consider the application constraints in target tracking sensor networks.

PYRO - new capability for isotopic mass tracking in pyroprocess simulation

International Nuclear Information System (INIS)

Liaw, J.R.; Ackerman, J.P.

1990-01-01

A new computational code package called PYRO has been developed to support the IFR fuel recycle demonstration project in the HFEF/S facility at ANL-W. The basic pyrochemical code PYRO1 1 models the atomic mass flows and phase compositions of 48 essential chemical elements involved in the pyroprocess. It has been extended to PYRO1 2 by linking with the ORIGEN code to track more than 1000 isotopic species, their radioactive decays, and related phenomena. This paper first describes the pyroprocess to be modeled and the pyrochemical capability that has been implemented in PYRO1 1 , and then gives a full account on the algorithm of extending it to PYRO1 2 for isotopic mass tracking. Results from several scoping and simulation runs will be discussed to illustrate the significance of modeling in process radioactive decays

Fast simulation of the forward tracking detector of HPLUS

International Nuclear Information System (INIS)

Zhang Yapeng; Fan Ruirui; Fu Fen; Yue Ke; Yuan Xiaohua; Xu Huagen; Chinese Academy of Sciences, Beijing; Yao Nan; Xu Hushan; Jin Genming; Liang Jinjie; Chen Ruofu; Sun Zhiyu; Duan Limin; Xiao Zhigang; Tsinghua Univ., Beijing

2008-01-01

The necessity of installing a forward tracking detector stack is discussed for the Hadron Physics Lanzhou Spectrometer(HPLUS). A local tracker is developed to solve the multi-track finding problem. The track candidates are searched iteratively via Hough Transform. The fake tracks are removed by a least square fitting process. With this tracker we have studied the feasibility of pp→pp+φ(→K + K - ), a typical physical channel proposed on HPLUS. The single track momentum resolution due to the uncertainty of the positioning in FTD is 1.3%. The multiple scattering effect contributes about 20% to the momentum resolution in the FTD coverage. The width and the signal-to-background ratio of the reconstructed φ are 1.51 MeV and 4.36, respectively, taking into account the direct Kaon channel pp→pp+K + K - as background. The geometry coverage of FTD for qb events is about 85.4%. Based on the current fast simulation and estimation, the geometrical configuration of FTD meets the physical requirement of HPLUS under the current luminosity and multiplicity conditions. The tracker is applicable in the full simulation coming next and is extendable to other tracking component of HPLUS. (authors)

Implementation of a vector-based tracking loop receiver in a pseudolite navigation system.

Science.gov (United States)

So, Hyoungmin; Lee, Taikjin; Jeon, Sanghoon; Kim, Chongwon; Kee, Changdon; Kim, Taehee; Lee, Sanguk

2010-01-01

We propose a vector tracking loop (VTL) algorithm for an asynchronous pseudolite navigation system. It was implemented in a software receiver and experiments in an indoor navigation system were conducted. Test results show that the VTL successfully tracks signals against the near-far problem, one of the major limitations in pseudolite navigation systems, and could improve positioning availability by extending pseudolite navigation coverage.

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.

Interacting with target tracking algorithms in a gaze-enhanced motion video analysis system

Science.gov (United States)

Hild, Jutta; Krüger, Wolfgang; Heinze, Norbert; Peinsipp-Byma, Elisabeth; Beyerer, Jürgen

2016-05-01

Motion video analysis is a challenging task, particularly if real-time analysis is required. It is therefore an important issue how to provide suitable assistance for the human operator. Given that the use of customized video analysis systems is more and more established, one supporting measure is to provide system functions which perform subtasks of the analysis. Recent progress in the development of automated image exploitation algorithms allow, e.g., real-time moving target tracking. Another supporting measure is to provide a user interface which strives to reduce the perceptual, cognitive and motor load of the human operator for example by incorporating the operator's visual focus of attention. A gaze-enhanced user interface is able to help here. This work extends prior work on automated target recognition, segmentation, and tracking algorithms as well as about the benefits of a gaze-enhanced user interface for interaction with moving targets. We also propose a prototypical system design aiming to combine both the qualities of the human observer's perception and the automated algorithms in order to improve the overall performance of a real-time video analysis system. In this contribution, we address two novel issues analyzing gaze-based interaction with target tracking algorithms. The first issue extends the gaze-based triggering of a target tracking process, e.g., investigating how to best relaunch in the case of track loss. The second issue addresses the initialization of tracking algorithms without motion segmentation where the operator has to provide the system with the object's image region in order to start the tracking algorithm.

Cost Cumulant-Based Control for a Class of Linear Quadratic Tracking Problems

National Research Council Canada - National Science Library

Pham, Khanh D

2007-01-01

.... For instance, the present paper extends the application of cost-cumulant controller design to control of a wide class of linear-quadratic tracking systems where output measurements of a tracker...

Seismic switch for strong motion measurement

Science.gov (United States)

Harben, P.E.; Rodgers, P.W.; Ewert, D.W.

1995-05-30

A seismic switching device is described that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period. 11 figs.

Software for precise tracking of cell proliferation

International Nuclear Information System (INIS)

Kurokawa, Hiroshi; Noda, Hisayori; Sugiyama, Mayu; Sakaue-Sawano, Asako; Fukami, Kiyoko; Miyawaki, Atsushi

2012-01-01

Highlights: ► We developed software for analyzing cultured cells that divide as well as migrate. ► The active contour model (Snakes) was used as the core algorithm. ► The time backward analysis was also used for efficient detection of cell division. ► With user-interactive correction functions, the software enables precise tracking. ► The software was successfully applied to cells with fluorescently-labeled nuclei. -- Abstract: We have developed a multi-target cell tracking program TADOR, which we applied to a series of fluorescence images. TADOR is based on an active contour model that is modified in order to be free of the problem of locally optimal solutions, and thus is resistant to signal fluctuation and morphological changes. Due to adoption of backward tracing and addition of user-interactive correction functions, TADOR is used in an off-line and semi-automated mode, but enables precise tracking of cell division. By applying TADOR to the analysis of cultured cells whose nuclei had been fluorescently labeled, we tracked cell division and cell-cycle progression on coverslips over an extended period of time.

Strong-stability-preserving additive linear multistep methods

KAUST Repository

Hadjimichael, Yiannis; Ketcheson, David I.

2018-01-01

The analysis of strong-stability-preserving (SSP) linear multistep methods is extended to semi-discretized problems for which different terms on the right-hand side satisfy different forward Euler (or circle) conditions. Optimal perturbed

PYRO: New capability for isotopic mass tracking in pyroprocess simulation

International Nuclear Information System (INIS)

Liaw, J.R.; Ackerman, J.P.

1990-01-01

A new computational code package called PYRO has been developed to support the IFR fuel recycle demonstration project in the HFEF/S facility at ANL-W. The basic pyrochemical code PYRO1-1 models the atomic mass flows and phase compositions of 48 essential chemical elements involved in the pyroprocess. It has been extended to PYRO1-2 by linking with the ORIGEN code to track more than 1000 isotopic species, their radioactive decays, and related phenomena. This paper first describes the pyroprocess to be modeled and the pyrochemical capability that has been implemented in PYRO1-1, and then gives a full account on the algorithm of extending it to PYRO1-2 for isotopic mass tracking. Results from several scoping and simulation runs will be discussed to illustrate the significance of modeling in-process radioactive decays. 16 refs., 8 figs., 2 tabs

Boolean Operations, Joins, and the Extended Low Hierarchy

OpenAIRE

Hemaspaandra, Lane A.; Jiang, Zhigen; Rothe, Joerg; Watanabe, Osamu

1999-01-01

We prove that the join of two sets may actually fall into a lower level of the extended low hierarchy than either of the sets. In particular, there exist sets that are not in the second level of the extended low hierarchy, EL_2, yet their join is in EL_2. That is, in terms of extended lowness, the join operator can lower complexity. Since in a strong intuitive sense the join does not lower complexity, our result suggests that the extended low hierarchy is unnatural as a complexity measure. We...

Strong enhancement of transport by interaction on contact links

DEFF Research Database (Denmark)

Bohr, Dan; Schmitteckert, P.

2007-01-01

Strong repulsive interactions within a one-dimensional Fermi system in a two-probe configuration normally lead to a reduced off-resonance conductance. We show that if the repulsive interaction extends to the contact regions, a strong increase of the conductance may occur, even for systems where o...

Tracking integration in concentrating photovoltaics using laterally moving optics.

Science.gov (United States)

Duerr, Fabian; Meuret, Youri; Thienpont, Hugo

2011-05-09

In this work the concept of tracking-integrated concentrating photovoltaics is studied and its capabilities are quantitatively analyzed. The design strategy desists from ideal concentration performance to reduce the external mechanical solar tracking effort in favor of a compact installation, possibly resulting in lower overall cost. The proposed optical design is based on an extended Simultaneous Multiple Surface (SMS) algorithm and uses two laterally moving plano-convex lenses to achieve high concentration over a wide angular range of ±24°. It achieves 500× concentration, outperforming its conventional concentrating photovoltaic counterparts on a polar aligned single axis tracker.

Studies for the ALICE inner tracking system upgrade

International Nuclear Information System (INIS)

Reidt, Felix

2016-01-01

The ALICE experiment at the CERN LHC identifies D"0 mesons via secondary-vertex reconstruction and topological cuts to reduce the corresponding combinatorial background in heavy-ion collisions. The D"0 meson is produced promptly in initial, hard scatterings via the strong interaction or as feed-down from weakly decaying B hadrons. Within this thesis, a novel method for the separation of prompt and feed-down D"0 mesons using cut variations was implemented and applied to data from p-Pb collisions at √(s_N_N)=5.02 TeV. The effectiveness of the secondary-vertex reconstruction strongly depends on the performance and in particular the pointing resolution of the Inner Tracking System. The upgrade of the ALICE Inner Tracking System for the Long Shutdown 2 of the LHC in 2019/2020 will significantly improve its vertex-reconstruction and tracking capabilities. It will be equipped with Monolithic Active Pixel Sensors manufactured using the TowerJazz 180 nm CMOS process on wafers with a high-resistivity epitaxial layer. In another part of this thesis, several pixel-chip prototypes of the ALPIDE architecture with in-pixel amplification and discrimination as well as in-matrix data reduction were characterised. The pALPIDE-2 prototype was measured to fulfil the requirements in terms of detection efficiency, fake-hit rate, position resolution and tolerance to irradiation with non-ionising energy loss. Based on simulations modelling the tracking and vertex-reconstruction performance of the upgraded Inner Tracking System, the perspective of the feed-down separation using cut variations after the upgrade was assessed within this thesis.

Quantitative observations on tropical cyclone tracks in the Arabian Sea

Science.gov (United States)

Terry, James P.; Gienko, Gennady

2018-03-01

The Arabian Sea basin represents a minor component of global total cyclones annually and has not featured so prominently in cyclone research compared with other basins where greater numbers of cyclones are registered each year. This paper presents the results of exploratory analysis of various features of cyclone tracks in the Arabian Sea, with a particular focus on examining their temporal and spatial patterns. Track morphometry also reveals further information on track shape. The study indicates how cyclones spawned during May in the early pre-monsoon period (often strong events) have a tendency to follow more sinuous tracks, whereas cyclones occurring in October in the post-monsoon period tend to follow straighter tracks. Track sinuosity is significantly related to other attributes, including cyclone longevity and intensity. Comparisons are also drawn between the general characteristics of cyclone tracks in the Arabian Sea and other ocean basins, suggesting how the size and geography of the Arabian Sea basin exert influences on these characteristics.

The extended arm of health professionals?

DEFF Research Database (Denmark)

Norlyk, Annelise; Martinsen, Bente

2013-01-01

responsibility for both the patient's well-being and for the patient's compliance with the daily regimen. Relatives were caught in a conflicting double role. They were the extended arm of the health professionals but also the caring, supporting partner. A tension arose between relatives' desire to help....... Due to the early discharge and the increasing demands on patients for self-care, patients' relatives seem to play a pivotal role in fast-track programmes. However, research is limited into how patients' close relatives are affected by and involved in the postoperative recovery process. Design...

Tracking shocked dust: State estimation for a complex plasma during a shock wave

International Nuclear Information System (INIS)

Oxtoby, Neil P.; Ralph, Jason F.; Durniak, Celine; Samsonov, Dmitry

2012-01-01

We consider a two-dimensional complex (dusty) plasma crystal excited by an electrostatically-induced shock wave. Dust particle kinematics in such a system are usually determined using particle tracking velocimetry. In this work we present a particle tracking algorithm which determines the dust particle kinematics with significantly higher accuracy than particle tracking velocimetry. The algorithm uses multiple extended Kalman filters to estimate the particle states and an interacting multiple model to assign probabilities to the different filters. This enables the determination of relevant physical properties of the dust, such as kinetic energy and kinetic temperature, with high precision. We use a Hugoniot shock-jump relation to calculate a pressure-volume diagram from the shocked dust kinematics. Calculation of the full pressure-volume diagram was possible with our tracking algorithm, but not with particle tracking velocimetry.

Development of Adaptive Tilt Tracker that Utilizes QUAD-cell Detector to Track Extended Objects

Science.gov (United States)

2014-03-17

tracked low Earth orbit (LEO) object and atmospheric seeing govern spot characteristics. Unlike static natural or laser guide stars, a LEO object’s...image spot characteristics .......................................................... 101 56. Response for non-adaptive tilt tracker with α equal to...applications toward natural and laser guide stars. The system was innovative and is a relevant forerunner to the tracker proposed in this research. The

Past, present and future of tourist tracking

Directory of Open Access Journals (Sweden)

Tatjana Thimm

2016-03-01

Full Text Available Purpose – The purpose of this paper is to find out tourism movement patterns via the tracking of tourists with the help of positioning systems like GPS in the rural area of the Lake Constance destination in Germany. In doing so past, present and future of tourist tracking is illustrated. Design/methodology/approach – The tracking is realized via common smartphones extended by an app, with dedicated sensors like position loggers and a survey. The three different approaches are applied in order to compare and cross-check results (triangulation of data and methods. Findings – Movement patterns turned out to be diverse and individualistic within the rural destination of Lake Constance and following an ants trail in sub-destinations like the city of Constance. Repeat visitors and first-time visitors alike always visit the bigger cities and main day-trip destinations of the Lake. A possible prediction tool enables new avenues of governing tourism movement patterns. Research limitations/implications – The tracking techniques can be developed further into the direction of “quantified self” using gamification in order to make the tracking app even more attractive. Practical implications – An algorithm-based prediction tool would offer new perspectives to the management of tourism movements. Social implications – Further research is needed to overcome the feeling of invasiveness of the app to allow tracking with that approach. Originality/value – This study is original and innovative because of the first-time use of a smartphone app in tourist tracking, the application on a rural destination and the conceptual description of a prediction tool.

Multiple feature fusion via covariance matrix for visual tracking

Science.gov (United States)

Jin, Zefenfen; Hou, Zhiqiang; Yu, Wangsheng; Wang, Xin; Sun, Hui

2018-04-01

Aiming at the problem of complicated dynamic scenes in visual target tracking, a multi-feature fusion tracking algorithm based on covariance matrix is proposed to improve the robustness of the tracking algorithm. In the frame-work of quantum genetic algorithm, this paper uses the region covariance descriptor to fuse the color, edge and texture features. It also uses a fast covariance intersection algorithm to update the model. The low dimension of region covariance descriptor, the fast convergence speed and strong global optimization ability of quantum genetic algorithm, and the fast computation of fast covariance intersection algorithm are used to improve the computational efficiency of fusion, matching, and updating process, so that the algorithm achieves a fast and effective multi-feature fusion tracking. The experiments prove that the proposed algorithm can not only achieve fast and robust tracking but also effectively handle interference of occlusion, rotation, deformation, motion blur and so on.

Person and gesture tracking with smart stereo cameras

Science.gov (United States)

Gordon, Gaile; Chen, Xiangrong; Buck, Ron

2008-02-01

Physical security increasingly involves sophisticated, real-time visual tracking of a person's location inside a given environment, often in conjunction with biometrics and other security-related technologies. However, demanding real-world conditions like crowded rooms, changes in lighting and physical obstructions have proved incredibly challenging for 2D computer vision technology. In contrast, 3D imaging technology is not affected by constant changes in lighting and apparent color, and thus allows tracking accuracy to be maintained in dynamically lit environments. In addition, person tracking with a 3D stereo camera can provide the location and movement of each individual very precisely, even in a very crowded environment. 3D vision only requires that the subject be partially visible to a single stereo camera to be correctly tracked; multiple cameras are used to extend the system's operational footprint, and to contend with heavy occlusion. A successful person tracking system, must not only perform visual analysis robustly, but also be small, cheap and consume relatively little power. The TYZX Embedded 3D Vision systems are perfectly suited to provide the low power, small footprint, and low cost points required by these types of volume applications. Several security-focused organizations, including the U.S Government, have deployed TYZX 3D stereo vision systems in security applications. 3D image data is also advantageous in the related application area of gesture tracking. Visual (uninstrumented) tracking of natural hand gestures and movement provides new opportunities for interactive control including: video gaming, location based entertainment, and interactive displays. 2D images have been used to extract the location of hands within a plane, but 3D hand location enables a much broader range of interactive applications. In this paper, we provide some background on the TYZX smart stereo cameras platform, describe the person tracking and gesture tracking systems

Multi-Target Tracking via Mixed Integer Optimization

Science.gov (United States)

2016-05-13

an easily interpretable global objective function. Furthermore, we propose a greedy heuristic which quickly finds good solutions. We extend both the... heuristic and the MIO model to scenarios with missed detections and false alarms. Index Terms—optimization; multi-target tracking; data asso- ciation...energy in [14] and then again as a minimization of discrete-continuous energy in [15]. These algorithms aim to more accurately represent the nature of the

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)

False-vacuum decay in generalized extended inflation

International Nuclear Information System (INIS)

Holman, R.; Wang Yun; Kolb, E.W.; Chicago Univ., IL; Chicago Univ., IL; Vadas, S.L.

1990-01-01

We study false-vacuum decay in the context of generalized extended inflationary theories, and compute the bubble nucleation rates for these theories in the limit of G N →0. We find that the time dependence of the nucleation rate can be exponentially strong through the time dependence of the Jordan-Brans-Dicke field. This can have a pronounced effect on whether extended inflation can be succesfully implemented. (orig.)

Fast neural-net based fake track rejection in the LHCb reconstruction

CERN Document Server

De Cian, Michel; Seyfert, Paul; Stahl, Sascha

2017-01-01

A neural-network based algorithm to identify fake tracks in the LHCb pattern recognition is presented. This algorithm, called ghost probability, retains more than 99 % of well reconstructed tracks while reducing the number of fake tracks by 60 %. It is fast enough to fit into the CPU time budget of the software trigger farm and thus reduces the combinatorics of the decay reconstructions, as well as the number of tracks that need to be processed by the particle identification algorithms. As a result, it strongly contributes to the achievement of having the same reconstruction online and offline in the LHCb experiment in Run II of the LHC.

Studies for the ALICE inner tracking system upgrade

Energy Technology Data Exchange (ETDEWEB)

Reidt, Felix

2016-04-28

The ALICE experiment at the CERN LHC identifies D{sup 0} mesons via secondary-vertex reconstruction and topological cuts to reduce the corresponding combinatorial background in heavy-ion collisions. The D{sup 0} meson is produced promptly in initial, hard scatterings via the strong interaction or as feed-down from weakly decaying B hadrons. Within this thesis, a novel method for the separation of prompt and feed-down D{sup 0} mesons using cut variations was implemented and applied to data from p-Pb collisions at √(s{sub NN})=5.02 TeV. The effectiveness of the secondary-vertex reconstruction strongly depends on the performance and in particular the pointing resolution of the Inner Tracking System. The upgrade of the ALICE Inner Tracking System for the Long Shutdown 2 of the LHC in 2019/2020 will significantly improve its vertex-reconstruction and tracking capabilities. It will be equipped with Monolithic Active Pixel Sensors manufactured using the TowerJazz 180 nm CMOS process on wafers with a high-resistivity epitaxial layer. In another part of this thesis, several pixel-chip prototypes of the ALPIDE architecture with in-pixel amplification and discrimination as well as in-matrix data reduction were characterised. The pALPIDE-2 prototype was measured to fulfil the requirements in terms of detection efficiency, fake-hit rate, position resolution and tolerance to irradiation with non-ionising energy loss. Based on simulations modelling the tracking and vertex-reconstruction performance of the upgraded Inner Tracking System, the perspective of the feed-down separation using cut variations after the upgrade was assessed within this thesis.

On Improving the Energy Efficiency and Robustness of Position Tracking for Mobile Devices

DEFF Research Database (Denmark)

Kjærgaard, Mikkel Baun

2010-01-01

position updates when faced with changing conditions such as delays and changing positioning conditions. Previous work has established dynamic tracking systems, such as our EnTracked system, as a solution to address these issues. In this paper we propose a responsibility division for position tracking...... into sensor management strategies and position update protocols and combine the sensor management strategy of EnTracked with position update protocols, which enables the system to further reduce the power consumption with up to 268 mW extending the battery life with up to 36\\%. As our evaluation identify...... that classical position update protocols have robustness weaknesses we propose a method to improve their robustness. Furthermore, we analyze the dependency of tracking systems on the pedestrian movement patterns and positioning environment, and how the power savings depend on the power characteristics...

Stabilization and tracking controller for a class of nonlinear discrete-time systems

International Nuclear Information System (INIS)

Sharma, B.B.; Kar, I.N.

2011-01-01

Highlights: → We present recursive design of stabilizing controller for nonlinear discrete-time systems. → Problem of stabilizing and tracking control of single link manipulator system is addressed. → We extend the proposed results to output tracking problems. → The proposed methodology is applied satisfactorily to discrete-time chaotic maps. - Abstract: In this paper, stabilization and tracking control problem for parametric strict feedback class of discrete time systems is addressed. Recursive design of control function based on contraction theory framework is proposed instead of traditional Lyapunov based method. Explicit structure of controller is derived for the addressed class of nonlinear discrete-time systems. Conditions for exponential stability of system states are derived in terms of controller parameters. At each stage of recursive procedure a specific structure of Jacobian matrix is ensured so as to satisfy conditions of stability. The closed loop dynamics in this case remains nonlinear in nature. The proposed algorithm establishes global stability results in quite a simple manner as it does not require formulation of error dynamics. Problem of stabilization and output tracking control in case of single link manipulator system with actuator dynamics is analyzed using the proposed strategy. The proposed results are further extended to stabilization of discrete time chaotic systems. Numerical simulations presented in the end show the effectiveness of the proposed approach.

Order Tracking Based on Robust Peak Search Instantaneous Frequency Estimation

International Nuclear Information System (INIS)

Gao, Y; Guo, Y; Chi, Y L; Qin, S R

2006-01-01

Order tracking plays an important role in non-stationary vibration analysis of rotating machinery, especially to run-up or coast down. An instantaneous frequency estimation (IFE) based order tracking of rotating machinery is introduced. In which, a peak search algorithms of spectrogram of time-frequency analysis is employed to obtain IFE of vibrations. An improvement to peak search is proposed, which can avoid strong non-order components or noises disturbing to the peak search work. Compared with traditional methods of order tracking, IFE based order tracking is simplified in application and only software depended. Testing testify the validity of the method. This method is an effective supplement to traditional methods, and the application in condition monitoring and diagnosis of rotating machinery is imaginable

A Provenance Tracking Model for Data Updates

Directory of Open Access Journals (Sweden)

Gabriel Ciobanu

2012-08-01

Full Text Available For data-centric systems, provenance tracking is particularly important when the system is open and decentralised, such as the Web of Linked Data. In this paper, a concise but expressive calculus which models data updates is presented. The calculus is used to provide an operational semantics for a system where data and updates interact concurrently. The operational semantics of the calculus also tracks the provenance of data with respect to updates. This provides a new formal semantics extending provenance diagrams which takes into account the execution of processes in a concurrent setting. Moreover, a sound and complete model for the calculus based on ideals of series-parallel DAGs is provided. The notion of provenance introduced can be used as a subjective indicator of the quality of data in concurrent interacting systems.

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.

Identifying elemental genomic track types and representing them uniformly

Directory of Open Access Journals (Sweden)

Gundersen Sveinung

2011-12-01

Full Text Available Abstract Background With the recent advances and availability of various high-throughput sequencing technologies, data on many molecular aspects, such as gene regulation, chromatin dynamics, and the three-dimensional organization of DNA, are rapidly being generated in an increasing number of laboratories. The variation in biological context, and the increasingly dispersed mode of data generation, imply a need for precise, interoperable and flexible representations of genomic features through formats that are easy to parse. A host of alternative formats are currently available and in use, complicating analysis and tool development. The issue of whether and how the multitude of formats reflects varying underlying characteristics of data has to our knowledge not previously been systematically treated. Results We here identify intrinsic distinctions between genomic features, and argue that the distinctions imply that a certain variation in the representation of features as genomic tracks is warranted. Four core informational properties of tracks are discussed: gaps, lengths, values and interconnections. From this we delineate fifteen generic track types. Based on the track type distinctions, we characterize major existing representational formats and find that the track types are not adequately supported by any single format. We also find, in contrast to the XML formats, that none of the existing tabular formats are conveniently extendable to support all track types. We thus propose two unified formats for track data, an improved XML format, BioXSD 1.1, and a new tabular format, GTrack 1.0. Conclusions The defined track types are shown to capture relevant distinctions between genomic annotation tracks, resulting in varying representational needs and analysis possibilities. The proposed formats, GTrack 1.0 and BioXSD 1.1, cater to the identified track distinctions and emphasize preciseness, flexibility and parsing convenience.

Calibration of PM-355 nuclear track detectors for low-energy deuterons

International Nuclear Information System (INIS)

Malinowski, K.; Skladnik-Sadowska, E.; Sadowski, M.J.; Czaus, K.

2008-01-01

A dependence of track diameters on deuteron energy was investigated for PM-355 nuclear track detectors. Deuteron streams were obtained from RPI-IBIS facility at the pulsed injection of deuterium. Mass and energy analysis was performed with a Thomson-type spectrometer and PM-355 samples. An etched deuteron parabola extended from about 20 keV to about 500 keV. The energy resolution of measurements on the parabola at 20 keV was ±0.2keV, and at 500 keV amounted to ±50keV. Accuracy of the determination of deuteron energies decreased for higher energy values. Results are presented in diagrams showing the track diameters as a function of deuteron energy for chosen etching times (1-8 h)

Ageing effects on polymeric track detectors: studies of etched tracks at nano size scale using atomic force microscope

International Nuclear Information System (INIS)

Espinosa, G.; Golzarri, J. I.; Fragoso, R.; Vazquez L, C.; Saad, A. F.; El-Namrouty, A. A.; Fujii, M.

2012-01-01

Among several different techniques to analyze material surface, the use of Atomic Force Microscope is one of the finest method. As we know, the sensitivity to detect energetic ions is extremely affected during the storage time and conditions of the polymeric material used as a nuclear track detector. On the basis of the surface analysis of several track detector materials, we examined the detection sensitivity of these detectors exposed to alpha particles. The preliminary results revealed that the ageing effect on its sensitivity is very strong, that need to be considered on the routine applications or research experiments. The results are consistent with the experimental data in the literature. (Author)

Strong converse theorems using Rényi entropies

Energy Technology Data Exchange (ETDEWEB)

Leditzky, Felix; Datta, Nilanjana [Statistical Laboratory, Centre for Mathematical Sciences, University of Cambridge, Cambridge CB3 0WB (United Kingdom); Wilde, Mark M. [Department of Physics and Astronomy, Center for Computation and Technology, Hearne Institute for Theoretical Physics, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)

2016-08-15

We use a Rényi entropy method to prove strong converse theorems for certain information-theoretic tasks which involve local operations and quantum (or classical) communication between two parties. These include state redistribution, coherent state merging, quantum state splitting, measurement compression with quantum side information, randomness extraction against quantum side information, and data compression with quantum side information. The method we employ in proving these results extends ideas developed by Sharma [preprint http://arxiv.org/abs/1404.5940 [quant-ph] (2014)], which he used to give a new proof of the strong converse theorem for state merging. For state redistribution, we prove the strong converse property for the boundary of the entire achievable rate region in the (e, q)-plane, where e and q denote the entanglement cost and quantum communication cost, respectively. In the case of measurement compression with quantum side information, we prove a strong converse theorem for the classical communication cost, which is a new result extending the previously known weak converse. For the remaining tasks, we provide new proofs for strong converse theorems previously established using smooth entropies. For each task, we obtain the strong converse theorem from explicit bounds on the figure of merit of the task in terms of a Rényi generalization of the optimal rate. Hence, we identify candidates for the strong converse exponents for each task discussed in this paper. To prove our results, we establish various new entropic inequalities, which might be of independent interest. These involve conditional entropies and mutual information derived from the sandwiched Rényi divergence. In particular, we obtain novel bounds relating these quantities, as well as the Rényi conditional mutual information, to the fidelity of two quantum states.

Orchestrating care through the fast-track perspective: Orthopaedic nurses’ perceptions and experiences of providing individualised nursing care in older patients’ standardised fast-track programmes after total hip or knee replacement

DEFF Research Database (Denmark)

Bøttcher Berthelsen, Connie; Frederiksen, Kirsten

2017-01-01

The lack of individualised care in orthopaedic regimes is often explained by the extended use of patient pathways and clinical guidelines. The aim of this study was to illuminate orthopaedic nurses' perceptions and experiences of providing individual nursing care for older patients in standardised...... fast-track programmes after total hip or knee replacement. Ten semi-structured interviews were conducted with orthopaedic nurses in orthopaedic wards at three Danish hospitals between April and June of 2015. Data were analysed using manifest and latent content analysis according to Graneheim...... and Lundman. The main theme of the overall interpretation was Orchestrating care through the fast-track perspective, accompanied by three sub-themes: Identifying and legitimising relevant individual care in the fast-track programme, Struggling to fit all patients in the fast-track programme and Justifying...

On the penetration of etchant into tracks in polycarbonate

International Nuclear Information System (INIS)

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

2000-01-01

The time dependence of the uptake of NaOH/LiOH etchant in pristine polycarbonate (PC) and in PC irradiated with 3 GeV Pb ions has been examined. Different stages of etchant penetration can be distinguished. The overall surface-near etchant uptake along tracks is always higher than the the one of the nonirradiated pristine material. Furthermore, the directional dependence of the etchant penetration during the incubation time is studied. Though the shapes of the etchant distributions along the tracks are practically the same in all directions, they differ in their absolute magnitudes. This can be explained by the different cross-sectional track areas exposed at the surface, which enable different etchant penetration efficiencies. Therefore, tracks which run more or less parallel to the surface normal show less etchant uptake than those being strongly tilted

Strong laws for L- and U-statistics

NARCIS (Netherlands)

Aaronson, J; Burton, R; Dehling, H; Gilat, D; Hill, T; Weiss, B

Strong laws of large numbers are given for L-statistics (linear combinations of order statistics) and for U-statistics (averages of kernels of random samples) for ergodic stationary processes, extending classical theorems; of Hoeffding and of Helmers for lid sequences. Examples are given to show

Effect of track etch rate on geometric track characteristics for polymeric track detectors

International Nuclear Information System (INIS)

Abdel-Naby, A.A.; El-Akkad, F.A.

2001-01-01

Analysis of the variable track etch rate on geometric track characteristic for polymeric track detectors has been applied to the case of LR-155 II SSNTD. Spectrometric characteristics of low energy alpha particles response by the polymeric detector have been obtained. The track etching kinematics theory of development of minor diameter of the etched tracks has been applied. The calculations show that, for this type of detector, the energy dependence of the minor track diameter d is linear for small-etched removal layer h. The energy resolution gets better for higher etched removal layer

Orchestrating care through the fast-track perspective: A qualitative content analysis of the provision of individualised nursing care in orthopaedic fast-track programmes.

Science.gov (United States)

Berthelsen, Connie Bøttcher; Frederiksen, Kirsten

2017-02-01

The lack of individualised care in orthopaedic regimes is often explained by the extended use of patient pathways and clinical guidelines. The aim of this study was to illuminate orthopaedic nurses' perceptions and experiences of providing individual nursing care for older patients in standardised fast-track programmes after total hip or knee replacement. Ten semi-structured interviews were conducted with orthopaedic nurses in orthopaedic wards at three Danish hospitals between April and June of 2015. Data were analysed using manifest and latent content analysis according to Graneheim and Lundman. The main theme of the overall interpretation was Orchestrating care through the fast-track perspective, accompanied by three sub-themes: Identifying and legitimising relevant individual care in the fast-track programme, Struggling to fit all patients in the fast-track programme and Justifying individualised care-related actions in the fast-track programme. The study concluded that, even though the nurses struggled to comply with the programme, they still found themselves compromising their nursing care and ethics to follow the standardised regime. There is a need to establish more specific inclusion criteria to maintain the effective elements in the programme and to facilitate nurses' opportunities to offer individual care, thereby ensuring that fragile patients have access to other possibilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fast neutron radiography of extended biological and medical objects

International Nuclear Information System (INIS)

Duehmke, E.; Greim, L.

1978-01-01

The fast neutron radiography enables us to image extended objects and yields quite different pictures than conventional roentgenograms. Using foils of cellulose nitrate and the track etching technique a γ-ray-insensitive detector is available providing sufficient imaging qualities. One of the biological neutrograms shown in the paper is of special importance because one can see a malignant tumor of the columna vertebralis. This finding was not detectable by roentgenological examination. (orig.) [de

Track-monitoring from the dynamic response of an operational train

Science.gov (United States)

Lederman, George; Chen, Siheng; Garrett, James; Kovačević, Jelena; Noh, Hae Young; Bielak, Jacobo

2017-03-01

We explore a data-driven approach for monitoring rail infrastructure from the dynamic response of a train in revenue-service. Presently, track inspection is performed either visually or with dedicated track geometry cars. In this study, we examine a more economical approach where track inspection is performed by analyzing vibration data collected from an operational passenger train. The high frequency with which passenger trains travel each section of track means that faults can be detected sooner than with dedicated inspection vehicles, and the large number of passes over each section of track makes a data-driven approach statistically feasible. We have deployed a test-system on a light-rail vehicle and have been collecting data for the past two years. The collected data underscores two of the main challenges that arise in train-based track monitoring: the speed of the train at a given location varies from pass to pass and the position of the train is not known precisely. In this study, we explore which feature representations of the data best characterize the state of the tracks despite these sources of uncertainty (i.e., in the spatial domain or frequency domain), and we examine how consistently change detection approaches can identify track changes from the data. We show the accuracy of these different representations, or features, and different change detection approaches on two types of track changes, track replacement and tamping (a maintenance procedure to improve track geometry), and two types of data, simulated data and operational data from our test-system. The sensing, signal processing, and data analysis we propose in the study could facilitate safer trains and more cost-efficient maintenance in the future. Moreover, the proposed approach is quite general and could be extended to other parts of the infrastructure, including bridges.

Real Time 3D Facial Movement Tracking Using a Monocular Camera

Directory of Open Access Journals (Sweden)

Yanchao Dong

2016-07-01

Full Text Available The paper proposes a robust framework for 3D facial movement tracking in real time using a monocular camera. It is designed to estimate the 3D face pose and local facial animation such as eyelid movement and mouth movement. The framework firstly utilizes the Discriminative Shape Regression method to locate the facial feature points on the 2D image and fuses the 2D data with a 3D face model using Extended Kalman Filter to yield 3D facial movement information. An alternating optimizing strategy is adopted to fit to different persons automatically. Experiments show that the proposed framework could track the 3D facial movement across various poses and illumination conditions. Given the real face scale the framework could track the eyelid with an error of 1 mm and mouth with an error of 2 mm. The tracking result is reliable for expression analysis or mental state inference.

PMHT Approach for Multi-Target Multi-Sensor Sonar Tracking in Clutter.

Science.gov (United States)

Li, Xiaohua; Li, Yaan; Yu, Jing; Chen, Xiao; Dai, Miao

2015-11-06

Multi-sensor sonar tracking has many advantages, such as the potential to reduce the overall measurement uncertainty and the possibility to hide the receiver. However, the use of multi-target multi-sensor sonar tracking is challenging because of the complexity of the underwater environment, especially the low target detection probability and extremely large number of false alarms caused by reverberation. In this work, to solve the problem of multi-target multi-sensor sonar tracking in the presence of clutter, a novel probabilistic multi-hypothesis tracker (PMHT) approach based on the extended Kalman filter (EKF) and unscented Kalman filter (UKF) is proposed. The PMHT can efficiently handle the unknown measurements-to-targets and measurements-to-transmitters data association ambiguity. The EKF and UKF are used to deal with the high degree of nonlinearity in the measurement model. The simulation results show that the proposed algorithm can improve the target tracking performance in a cluttered environment greatly, and its computational load is low.

Low Complexity Track Initialization from a Small Set of Non-Invertible Measurements

Directory of Open Access Journals (Sweden)

Wolfgang Koch

2008-02-01

Full Text Available Target tracking from non-invertible measurement sets, for example, incomplete spherical coordinates measured by asynchronous sensors in a sensor network, is a task of data fusion present in a lot of applications. Difficulties in tracking using extended Kalman filters lead to unstable behavior, mainly caused by poor initialization. Instead of using high complexity numerical batch-estimators, we offer an analytical approach to initialize the filter from a minimum number of observations. This directly pertains to multi-hypothesis tracking (MHT, where in the presence of clutter and/or multiple targets (i low complexity algorithms are desirable and (ii using a small set of measurements avoids the combinatorial explosion. Our approach uses no numerical optimization, simply evaluating several equations to find the state estimates. This is possible since we avoid an over-determined setup by initializing only from the minimum necessary subset of measurements. Loss in accuracy is minimized by choosing the best subset using an optimality criterion and incorporating the leftover measurements afterwards. Additionally, we provide the possibility to estimate only sub-sets of parameters, and to reliably model the resulting added uncertainties by the covariance matrix. We compare two different implementations, differing in the approximation of the posterior: linearizing the measurement equation as in the extended Kalman filter (EKF or employing the unscented transform (UT. The approach will be studied in two practical examples: 3D track initialization using bearingsonly measurements or using slant-range and azimuth only.

Strong Relaxations for the Train Timetabling Problem Using Connected Configurations

OpenAIRE

Fischer, Frank; Schlechte, Thomas

2017-01-01

The task of the train timetabling problem or track allocation problem is to find conflict free schedules for a set of trains with predefined routes in a railway network. Especially for non-periodic instances models based on time expanded networks are often used. Unfortunately, the linear programming relaxation of these models is often extremely weak because these models do not describe combinatorial relations like overtaking possibilities very well. In this paper we extend the model by so cal...

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.

OBJECT TRACKING WITH ROTATION-INVARIANT LARGEST DIFFERENCE INDEXED LOCAL TERNARY PATTERN

Directory of Open Access Journals (Sweden)

J Shajeena

2017-02-01

Full Text Available This paper presents an ideal method for object tracking directly in the compressed domain in video sequences. An enhanced rotation-invariant image operator called Largest Difference Indexed Local Ternary Pattern (LDILTP has been proposed. The Local Ternary Pattern which worked very well in texture classification and face recognition is now extended for rotation invariant object tracking. Histogramming the LTP code makes the descriptor resistant to translation. The histogram intersection is used to find the similarity measure. This method is robust to noise and retain contrast details. The proposed scheme has been verified on various datasets and shows a commendable performance.

Communication: Relaxation-limited electronic currents in extended reservoir simulations

Science.gov (United States)

Gruss, Daniel; Smolyanitsky, Alex; Zwolak, Michael

2017-10-01

Open-system approaches are gaining traction in the simulation of charge transport in nanoscale and molecular electronic devices. In particular, "extended reservoir" simulations, where explicit reservoir degrees of freedom are present, allow for the computation of both real-time and steady-state properties but require relaxation of the extended reservoirs. The strength of this relaxation, γ, influences the conductance, giving rise to a "turnover" behavior analogous to Kramers turnover in chemical reaction rates. We derive explicit, general expressions for the weak and strong relaxation limits. For weak relaxation, the conductance increases linearly with γ and every electronic state of the total explicit system contributes to the electronic current according to its "reduced" weight in the two extended reservoir regions. Essentially, this represents two conductors in series—one at each interface with the implicit reservoirs that provide the relaxation. For strong relaxation, a "dual" expression-one with the same functional form-results, except now proportional to 1/γ and dependent on the system of interest's electronic states, reflecting that the strong relaxation is localizing electrons in the extended reservoirs. Higher order behavior (e.g., γ2 or 1/γ2) can occur when there is a gap in the frequency spectrum. Moreover, inhomogeneity in the frequency spacing can give rise to a pseudo-plateau regime. These findings yield a physically motivated approach to diagnosing numerical simulations and understanding the influence of relaxation, and we examine their occurrence in both simple models and a realistic, fluctuating graphene nanoribbon.

Design studies for a tracking upgrade of the Crystal Barrel experiment at ELSA and installation of tracking test bench

International Nuclear Information System (INIS)

Winnebeck, Alexander

2009-01-01

Ever since mankind was interested in the understanding of the universe and especially the matter in it. The fundamental building blocks of matter seem to be quarks and gluons, whose interactions are investigated in hadron physics. To study this strong interaction different experimental approaches can be used. One way is to do spectroscopy similar to atomic physics. The Crystal Barrel experiment at ELSA performs spectroscopy of nucleons to learn more about the strong interaction. A major improvement of this experimental setup will be the introducing of charged particle tracking as it is shown in this thesis. Different detector concepts are discussed concerning feasibility, material budget and especially momentum resolution. It turns out that a Time Projection Chamber (TPC) is the optimal solution. Then it is shown how a prototype TPC is tested using a newly installed tracking test bench with an electron beam, and obtained results are presented. The design of the final TPC and its integration into the Crystal Barrel experiment are discussed as well as methods to calibrate the detector. (orig.)

Design studies for a tracking upgrade of the Crystal Barrel experiment at ELSA and installation of tracking test bench

Energy Technology Data Exchange (ETDEWEB)

Winnebeck, Alexander

2009-12-17

Ever since mankind was interested in the understanding of the universe and especially the matter in it. The fundamental building blocks of matter seem to be quarks and gluons, whose interactions are investigated in hadron physics. To study this strong interaction different experimental approaches can be used. One way is to do spectroscopy similar to atomic physics. The Crystal Barrel experiment at ELSA performs spectroscopy of nucleons to learn more about the strong interaction. A major improvement of this experimental setup will be the introducing of charged particle tracking as it is shown in this thesis. Different detector concepts are discussed concerning feasibility, material budget and especially momentum resolution. It turns out that a Time Projection Chamber (TPC) is the optimal solution. Then it is shown how a prototype TPC is tested using a newly installed tracking test bench with an electron beam, and obtained results are presented. The design of the final TPC and its integration into the Crystal Barrel experiment are discussed as well as methods to calibrate the detector. (orig.)

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

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

An improved tracking framework for ultrasound probe localization in image-guided radiosurgery

Directory of Open Access Journals (Sweden)

Ipsen Svenja

2016-09-01

Full Text Available Real-time target localization with ultrasound holds high potential for image guidance and motion compensation in radiosurgery due to its non-invasive image acquisition free from ionizing radiation. However, a two-step localization has to be performed when integrating ultrasound into the existing radiosurgery workflow. In addition to target localization inside the ultrasound volume, the probe itself has to be localized in order to transform the target position into treatment room coordinates. By adapting existing camera calibration tools, we have developed a method to extend the stereoscopic X-ray tracking system of a radiosurgery platform in order to locate objects such as marker geometries with six degrees of freedom. The calibration was performed with 0.1 mm reprojection error. By using the full area of the flat-panel detectors without pre-processing the extended software increased the tracking volume and resolution by up to 80%, substantially improving patient localization and marker detectability. Furthermore, marker-tracking showed sub-millimeter accuracy and rotational errors below 0.1°. This demonstrates that the developed extension framework can accurately localize marker geometries using an integrated X-ray system, establishing the link for the integration of real-time ultrasound image guidance into the existing system.

Extended recency effect extended: blocking, presentation mode, and retention interval.

Science.gov (United States)

Glidden, L M; Pawelski, C; Mar, H; Zigman, W

1979-07-01

The effect of blocking of stimulus items on the free recall of EMR adolescents was examined. In Experiment 1 a multitrial free-recall list of 15 pictures was presented either simultaneously in groups of 3, or sequentially, one at a time. Consistent ordering was used in both conditions, so that on each trial, each item in each set of 3 pictures was presented contiguously with the other 2 items from that set. In addition, recall came immediately or after a filled or unfilled delay of 24.5 seconds. Results showed that simultaneous presentation led to higher recall, subjective organization, and clustering than did sequential presentation, but analysis of serial-position curves showed a much reduced extended recency effect in comparison with previous studies. Experiment 2 was designed to determine whether the cause of the reduced extended recency was the use of pictures rather than words as stimuli. Stimuli were presented either as pictures, as pictures with auditory labels, or as words with auditory labels, with both simultaneous and consistent ordering for all conditions. Results indicated a strong extended recency effect for all groups, eliminating presentation mode as a causal factor in the data of Experiment 1. We concluded that blocking leads to increased organization and recall over a variety of presentation modes, rates, and block sizes.

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.

The deep space 1 extended mission

Science.gov (United States)

Rayman, Marc D.; Varghese, Philip

2001-03-01

The primary mission of Deep Space 1 (DS1), the first flight of the New Millennium program, completed successfully in September 1999, having exceeded its objectives of testing new, high-risk technologies important for future space and Earth science missions. DS1 is now in its extended mission, with plans to take advantage of the advanced technologies, including solar electric propulsion, to conduct an encounter with comet 19P/Borrelly in September 2001. During the extended mission, the spacecraft's commercial star tracker failed; this critical loss prevented the spacecraft from achieving three-axis attitude control or knowledge. A two-phase approach to recovering the mission was undertaken. The first involved devising a new method of pointing the high-gain antenna to Earth using the radio signal received at the Deep Space Network as an indicator of spacecraft attitude. The second was the development of new flight software that allowed the spacecraft to return to three-axis operation without substantial ground assistance. The principal new feature of this software is the use of the science camera as an attitude sensor. The differences between the science camera and the star tracker have important implications not only for the design of the new software but also for the methods of operating the spacecraft and conducting the mission. The ambitious rescue was fully successful, and the extended mission is back on track.

Strong-interaction nonuniversality

International Nuclear Information System (INIS)

Volkas, R.R.; Foot, R.; He, X.; Joshi, G.C.

1989-01-01

The universal QCD color theory is extended to an SU(3) 1 direct product SU(3) 2 direct product SU(3) 3 gauge theory, where quarks of the ith generation transform as triplets under SU(3)/sub i/ and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements

Extending the reach of strong-coupling: an iterative technique for Hamiltonian lattice models

International Nuclear Information System (INIS)

Alberty, J.; Greensite, J.; Patkos, A.

1983-12-01

The authors propose an iterative method for doing lattice strong-coupling-like calculations in a range of medium to weak couplings. The method is a modified Lanczos scheme, with greatly improved convergence properties. The technique is tested on the Mathieu equation and on a Hamiltonian finite-chain XY model, with excellent results. (Auth.)

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.

Sensor-Aware Recognition and Tracking for Wide-Area Augmented Reality on Mobile Phones

Science.gov (United States)

Chen, Jing; Cao, Ruochen; Wang, Yongtian

2015-01-01

Wide-area registration in outdoor environments on mobile phones is a challenging task in mobile augmented reality fields. We present a sensor-aware large-scale outdoor augmented reality system for recognition and tracking on mobile phones. GPS and gravity information is used to improve the VLAD performance for recognition. A kind of sensor-aware VLAD algorithm, which is self-adaptive to different scale scenes, is utilized to recognize complex scenes. Considering vision-based registration algorithms are too fragile and tend to drift, data coming from inertial sensors and vision are fused together by an extended Kalman filter (EKF) to achieve considerable improvements in tracking stability and robustness. Experimental results show that our method greatly enhances the recognition rate and eliminates the tracking jitters. PMID:26690439

Sensor-Aware Recognition and Tracking for Wide-Area Augmented Reality on Mobile Phones.

Science.gov (United States)

Chen, Jing; Cao, Ruochen; Wang, Yongtian

2015-12-10

Wide-area registration in outdoor environments on mobile phones is a challenging task in mobile augmented reality fields. We present a sensor-aware large-scale outdoor augmented reality system for recognition and tracking on mobile phones. GPS and gravity information is used to improve the VLAD performance for recognition. A kind of sensor-aware VLAD algorithm, which is self-adaptive to different scale scenes, is utilized to recognize complex scenes. Considering vision-based registration algorithms are too fragile and tend to drift, data coming from inertial sensors and vision are fused together by an extended Kalman filter (EKF) to achieve considerable improvements in tracking stability and robustness. Experimental results show that our method greatly enhances the recognition rate and eliminates the tracking jitters.

Sensor-Aware Recognition and Tracking for Wide-Area Augmented Reality on Mobile Phones

Directory of Open Access Journals (Sweden)

Jing Chen

2015-12-01

Full Text Available Wide-area registration in outdoor environments on mobile phones is a challenging task in mobile augmented reality fields. We present a sensor-aware large-scale outdoor augmented reality system for recognition and tracking on mobile phones. GPS and gravity information is used to improve the VLAD performance for recognition. A kind of sensor-aware VLAD algorithm, which is self-adaptive to different scale scenes, is utilized to recognize complex scenes. Considering vision-based registration algorithms are too fragile and tend to drift, data coming from inertial sensors and vision are fused together by an extended Kalman filter (EKF to achieve considerable improvements in tracking stability and robustness. Experimental results show that our method greatly enhances the recognition rate and eliminates the tracking jitters.

Tracking traders' understanding of the market using e-communication data.

Science.gov (United States)

Saavedra, Serguei; Duch, Jordi; Uzzi, Brian

2011-01-01

Tracking the volume of keywords in Internet searches, message boards, or Tweets has provided an alternative for following or predicting associations between popular interest or disease incidences. Here, we extend that research by examining the role of e-communications among day traders and their collective understanding of the market. Our study introduces a general method that focuses on bundles of words that behave differently from daily communication routines, and uses original data covering the content of instant messages among all day traders at a trading firm over a 40-month period. Analyses show that two word bundles convey traders' understanding of same day market events and potential next day market events. We find that when market volatility is high, traders' communications are dominated by same day events, and when volatility is low, communications are dominated by next day events. We show that the stronger the traders' attention to either same day or next day events, the higher their collective trading performance. We conclude that e-communication among traders is a product of mass collaboration over diverse viewpoints that embodies unique information about their weak or strong understanding of the market.

Tracking traders' understanding of the market using e-communication data.

Directory of Open Access Journals (Sweden)

Serguei Saavedra

Full Text Available Tracking the volume of keywords in Internet searches, message boards, or Tweets has provided an alternative for following or predicting associations between popular interest or disease incidences. Here, we extend that research by examining the role of e-communications among day traders and their collective understanding of the market. Our study introduces a general method that focuses on bundles of words that behave differently from daily communication routines, and uses original data covering the content of instant messages among all day traders at a trading firm over a 40-month period. Analyses show that two word bundles convey traders' understanding of same day market events and potential next day market events. We find that when market volatility is high, traders' communications are dominated by same day events, and when volatility is low, communications are dominated by next day events. We show that the stronger the traders' attention to either same day or next day events, the higher their collective trading performance. We conclude that e-communication among traders is a product of mass collaboration over diverse viewpoints that embodies unique information about their weak or strong understanding of the market.

An adaptive Multiplicative Extened Kalman Filter for Attitude Estimation of Marine Satellite Tracking Antenna

DEFF Research Database (Denmark)

Wang, Yunlong; Soltani, Mohsen; Hussain, Dil muhammed Akbar

2016-01-01

, an adaptive Multiplicative Extended Kalman Filter (MEKF) for attitude estimation of Marine Satellite Tracking Antenna (MSTA) is presented with the measurement noise covariance matrix adjusted according to the norm of accelerometer measurements, which can significantly reduce the slamming influence from waves...

Tracking Boulders

Science.gov (United States)

2006-01-01

13 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough in the Sirenum Fossae region. On the floor and walls of the trough, large -- truck- to house-sized -- boulders are observed at rest. However, there is evidence in this image for the potential for mobility. In the central portion of the south (bottom) wall, a faint line of depressions extends from near the middle of the wall, down to the rippled trough floor, ending very near one of the many boulders in the area. This line of depressions is a boulder track; it indicates the path followed by the boulder as it trundled downslope and eventually came to rest on the trough floor. Because it is on Mars, even when the boulder is sitting still, this once-rolling stone gathers no moss. Location near: 29.4oS, 146.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

The Visual Object Tracking VOT2016 Challenge Results

KAUST Repository

Kristan, Matej

2016-11-02

The Visual Object Tracking challenge VOT2016 aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 70 trackers are presented, with a large number of trackers being published at major computer vision conferences and journals in the recent years. The number of tested state-of-the-art trackers makes the VOT 2016 the largest and most challenging benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the Appendix. The VOT2016 goes beyond its predecessors by (i) introducing a new semi-automatic ground truth bounding box annotation methodology and (ii) extending the evaluation system with the no-reset experiment. The dataset, the evaluation kit as well as the results are publicly available at the challenge website (http://votchallenge.net).

The Visual Object Tracking VOT2016 Challenge Results

KAUST Repository

Kristan, Matej; Leonardis, Aleš; Matas, Jiři; Felsberg, Michael; Pflugfelder, Roman; Čehovin, Luka; Vojí r̃, Tomá š; Hä ger, Gustav; Lukežič, Alan; Ferná ndez, Gustavo; Gupta, Abhinav; Petrosino, Alfredo; Memarmoghadam, Alireza; Garcia-Martin, Alvaro; Solí s Montero, André s; Vedaldi, Andrea; Robinson, Andreas; Ma, Andy J.; Varfolomieiev, Anton; Alatan, Aydin; Erdem, Aykut; Ghanem, Bernard; Liu, Bin; Han, Bohyung; Martinez, Brais; Chang, Chang-Ming; Xu, Changsheng; Sun, Chong; Kim, Daijin; Chen, Dapeng; Du, Dawei; Mishra, Deepak; Yeung, Dit-Yan; Gundogdu, Erhan; Erdem, Erkut; Khan, Fahad; Porikli, Fatih; Zhao, Fei; Bunyak, Filiz; Battistone, Francesco; Zhu, Gao; Roffo, Giorgio; Subrahmanyam, Gorthi R. K. Sai; Bastos, Guilherme; Seetharaman, Guna; Medeiros, Henry; Li, Hongdong; Qi, Honggang; Bischof, Horst; Possegger, Horst; Lu, Huchuan; Lee, Hyemin; Nam, Hyeonseob; Chang, Hyung Jin; Drummond, Isabela; Valmadre, Jack; Jeong, Jae-chan; Cho, Jae-il; Lee, Jae-Yeong; Zhu, Jianke; Feng, Jiayi; Gao, Jin; Choi, Jin Young; Xiao, Jingjing; Kim, Ji-Wan; Jeong, Jiyeoup; Henriques, Joã o F.; Lang, Jochen; Choi, Jongwon; Martinez, Jose M.; Xing, Junliang; Gao, Junyu; Palaniappan, Kannappan; Lebeda, Karel; Gao, Ke; Mikolajczyk, Krystian; Qin, Lei; Wang, Lijun; Wen, Longyin; Bertinetto, Luca; Rapuru, Madan Kumar; Poostchi, Mahdieh; Maresca, Mario; Danelljan, Martin; Mueller, Matthias; Zhang, Mengdan; Arens, Michael; Valstar, Michel; Tang, Ming; Baek, Mooyeol; Khan, Muhammad Haris; Wang, Naiyan; Fan, Nana; Al-Shakarji, Noor; Miksik, Ondrej; Akin, Osman; Moallem, Payman; Senna, Pedro; Torr, Philip H. S.; Yuen, Pong C.; Huang, Qingming; Martin-Nieto, Rafael; Pelapur, Rengarajan; Bowden, Richard; Laganiè re, Robert; Stolkin, Rustam; Walsh, Ryan; Krah, Sebastian B.; Li, Shengkun; Zhang, Shengping; Yao, Shizeng; Hadfield, Simon; Melzi, Simone; Lyu, Siwei; Li, Siyi; Becker, Stefan; Golodetz, Stuart; Kakanuru, Sumithra; Choi, Sunglok; Hu, Tao; Mauthner, Thomas; Zhang, Tianzhu; Pridmore, Tony; Santopietro, Vincenzo; Hu, Weiming; Li, Wenbo; Hü bner, Wolfgang; Lan, Xiangyuan; Wang, Xiaomeng; Li, Xin; Li, Yang; Demiris, Yiannis; Wang, Yifan; Qi, Yuankai; Yuan, Zejian; Cai, Zexiong; Xu, Zhan; He, Zhenyu; Chi, Zhizhen

2016-01-01

The Visual Object Tracking challenge VOT2016 aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 70 trackers are presented, with a large number of trackers being published at major computer vision conferences and journals in the recent years. The number of tested state-of-the-art trackers makes the VOT 2016 the largest and most challenging benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the Appendix. The VOT2016 goes beyond its predecessors by (i) introducing a new semi-automatic ground truth bounding box annotation methodology and (ii) extending the evaluation system with the no-reset experiment. The dataset, the evaluation kit as well as the results are publicly available at the challenge website (http://votchallenge.net).

Adaptive Tracking Control of an Electro-Pneumatic Clutch Actuator

Directory of Open Access Journals (Sweden)

Glenn-Ole Kaasa

2003-10-01

Full Text Available This paper deals with the application of a simple adaptive algorithm for robust tracking control of an electro-pneumatic clutch actuator with output feedback. We present a mathematical model of the strongly nonlinear system, and implement an adaptive algorithm, based on a parallel feedforward compensator (PFC to remove the relative-degree-1 restriction. We propose a practical method of constructing the PFC, and introduce a simple modification that removes an inherent restriction on bandwidth of the nonlinear system. We show that the adaptive algorithm deals well with nonlinearities, and we achieve tracking corresponding to a settling-time of 150 ms.

Recurrent plot analysis of discharge sequences in tracking test of polybutylene polymers

Energy Technology Data Exchange (ETDEWEB)

Du, B X; Gu, L; Dong, D S [Key Laboratory of Power System Simulation and Control of Ministry of Education, Department of Electrical Engineering, School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Zheng, X L [Henan Electric Power Survey and Design Institute, Henan 450007 (China)], E-mail: duboxue@tju.edu.cn

2008-10-07

Polymers are required to use in radiation environments as insulation materials. However, they often suffer from tracking failure. There is an increasing demand to evaluate radiation effects on dielectric performance. This paper presents a recurrence plot (RP) approach to analyse surface discharge sequences of gamma-ray irradiated polymer materials based on tracking test. Studying the non-linear characteristics of discharge sequences can assist in understanding the underlying mechanism of the discharge process. Discharge sequences of the test are extended to m-dimensional phase space by using the phase space reconstructed method. As test samples, polybutylene terephthalate (PBT) and polybutylene naphthalate (PBN) were irradiated to 100 kGy and then up to 1 MGy with a dosage rate of 10 kGy h{sup -1} by using a {sup 60}Co gamma source. The tracking tests were carried out according to the test method described in IEC60112. It is found that the RPs can give visual recurrent patterns of discharge sequences for identification of the effects of gamma-ray radiation dosage on the resistance to tracking of the polymers. The detection of recurrent patterns together with comparative tracking index value results indicate that with the increase in the radiation dosage, the resistance to tracking of PBT decreases, but increases for PBN.

Strongly interacting matter in magnetic fields

CERN Document Server

Landsteiner, Karl; Schmitt, Andreas; Yee, Ho-Ung

2013-01-01

The physics of strongly interacting matter in an external magnetic field is presently emerging as a topic of great cross-disciplinary interest for particle, nuclear, astro- and condensed matter physicists. It is known that strong magnetic fields are created in heavy ion collisions, an insight that has made it possible to study a variety of surprising and intriguing phenomena that emerge from the interplay of quantum anomalies, the topology of non-Abelian gauge fields, and the magnetic field. In particular, the non-trivial topological configurations of the gluon field induce a non-dissipative electric current in the presence of a magnetic field. These phenomena have led to an extended formulation of relativistic hydrodynamics, called chiral magnetohydrodynamics. Hitherto unexpected applications in condensed matter physics include graphene and topological insulators. Other fields of application include astrophysics, where strong magnetic fields exist in magnetars and pulsars. Last but not least, an important ne...

Climate Data Provenance Tracking for Just-In-Time Computation

Science.gov (United States)

Fries, S.; Nadeau, D.; Doutriaux, C.; Williams, D. N.

2016-12-01

The "Climate Data Management System" (CDMS) was created in 1996 as part of the Climate Data Analysis Tools suite of software. It provides a simple interface into a wide variety of climate data formats, and creates NetCDF CF-Compliant files. It leverages the NumPy framework for high performance computation, and is an all-in-one IO and computation package. CDMS has been extended to track manipulations of data, and trace that data all the way to the original raw data. This extension tracks provenance about data, and enables just-in-time (JIT) computation. The provenance for each variable is packaged as part of the variable's metadata, and can be used to validate data processing and computations (by repeating the analysis on the original data). It also allows for an alternate solution for sharing analyzed data; if the bandwidth for a transfer is prohibitively expensive, the provenance serialization can be passed in a much more compact format and the analysis rerun on the input data. Data provenance tracking in CDMS enables far-reaching and impactful functionalities, permitting implementation of many analytical paradigms.

Strong Electroweak Symmetry Breaking

CERN Document Server

Grinstein, Benjamin

2011-01-01

Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

Relativistic parametric instabilities in extended extragalactic radio sources

Energy Technology Data Exchange (ETDEWEB)

Ferrari, A [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Trussoni, E; Zaninetti, L

1978-01-01

A general discussion is presented of parametric instabilities of electromagnetic waves in cold plasmas. Previous results for f = eE/msub(e)c..omega../sub 0/ >> 1 and << 1 are extended and the intermediate range f approximately 1, which could be relevant in some astrophysical applications, is analysed by numerical techniques. In the final section a model for particle acceleration and radiation emission by turbulent plasma modes excited in extended radiosources by parametric absorption of strong electromagnetic waves is tentatively discussed.

Multilevel tracking power supply for switch-mode audio power amplifiers

DEFF Research Database (Denmark)

Iversen, Niels Elkjær; Lazarevic, Vladan; Vasic, Miroslav

2018-01-01

to the power supply in order to improve efficiency. A 100 W prototype system was designed. Measured results show that systems employing envelope tracking can improve system efficiency from 2% to 12%, i.e. a factor of 6. The temperature rise is strongly reduced, especially for the switching power MOSFETs where......Switch-mode technology is the common choice for high efficiency audio power amplifiers. The dynamic nature of real audio reduces efficiency as less continuous output power can be achieved. Based on methods used for RF amplifiers this paper proposes to employ envelope tracking techniques...

Decision-Directed Recursive Least Squares MIMO Channels Tracking

Directory of Open Access Journals (Sweden)

Karami Ebrahim

2006-01-01

Full Text Available A new approach for joint data estimation and channel tracking for multiple-input multiple-output (MIMO channels is proposed based on the decision-directed recursive least squares (DD-RLS algorithm. RLS algorithm is commonly used for equalization and its application in channel estimation is a novel idea. In this paper, after defining the weighted least squares cost function it is minimized and eventually the RLS MIMO channel estimation algorithm is derived. The proposed algorithm combined with the decision-directed algorithm (DDA is then extended for the blind mode operation. From the computational complexity point of view being versus the number of transmitter and receiver antennas, the proposed algorithm is very efficient. Through various simulations, the mean square error (MSE of the tracking of the proposed algorithm for different joint detection algorithms is compared with Kalman filtering approach which is one of the most well-known channel tracking algorithms. It is shown that the performance of the proposed algorithm is very close to Kalman estimator and that in the blind mode operation it presents a better performance with much lower complexity irrespective of the need to know the channel model.

Compressed normalized block difference for object tracking

Science.gov (United States)

Gao, Yun; Zhang, Dengzhuo; Cai, Donglan; Zhou, Hao; Lan, Ge

2018-04-01

Feature extraction is very important for robust and real-time tracking. Compressive sensing provided a technical support for real-time feature extraction. However, all existing compressive tracking were based on compressed Haar-like feature, and how to compress many more excellent high-dimensional features is worth researching. In this paper, a novel compressed normalized block difference feature (CNBD) was proposed. For resisting noise effectively in a highdimensional normalized pixel difference feature (NPD), a normalized block difference feature extends two pixels in the original formula of NPD to two blocks. A CNBD feature can be obtained by compressing a normalized block difference feature based on compressive sensing theory, with the sparse random Gaussian matrix as the measurement matrix. The comparative experiments of 7 trackers on 20 challenging sequences showed that the tracker based on CNBD feature can perform better than other trackers, especially than FCT tracker based on compressed Haar-like feature, in terms of AUC, SR and Precision.

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.

Significant Value Found in Mentoring Programs for Novice Tenure-Track Academic Librarians

OpenAIRE

Saori Wendy Herman, MLIS, AHIP

2016-01-01

A Review of: Goodsett, M., & Walsh, A. (2015). Building a strong foundation: Mentoring programs for novice tenure-track librarians in academic libraries. College & Research Libraries, 76(7), 914-933. http://dx.doi.org/10.5860/crl.76.7.914 Objective – To examine the effectiveness of mentoring programs for novice tenure-track academic librarians, and to identify critical elements that define a successful mentoring program in various academic library settings. Design – Survey questionn...

Overview of the INEX 2014 Social Book Search Track

DEFF Research Database (Denmark)

Koolen, Marijn; Bogers, Toine; Kazai, Gabriella

2014-01-01

The goal of the INEX 2014 Social Book Search Track is to evaluate approaches for supporting users in searching collections of books based on book metadata and associated user-generated content. The track investigates the complex nature of relevance in book search and the role of traditional...... and user-generated book metadata in retrieval. We extended last year’s investigation into the nature of book suggestions from the LibraryThing forums and how they compare to book relevance judgements. Participants were encouraged to incorporate rich user profiles of both topic creators and other Library......Thing users to explore the relative value of recommendation and retrieval paradigms for book search. We found further support that such suggestions are a valuable alternative to traditional test collections that are based on top-k pooling and editorial relevance judgements....

Strong Coupling between Plasmons and Organic Semiconductors

Directory of Open Access Journals (Sweden)

Joel Bellessa

2014-05-01

Full Text Available In this paper we describe the properties of organic material in strong coupling with plasmon, mainly based on our work in this field of research. The strong coupling modifies the optical transitions of the structure, and occurs when the interaction between molecules and plasmon prevails on the damping of the system. We describe the dispersion relation of different plasmonic systems, delocalized and localized plasmon, coupled to aggregated dyes and the typical properties of these systems in strong coupling. The modification of the dye emission is also studied. In the second part, the effect of the microscopic structure of the organics, which can be seen as a disordered film, is described. As the different molecules couple to the same plasmon mode, an extended coherent state on several microns is observed.

Storm-Tracks in ERA-40 and ERA-Interim Reanalyses

Science.gov (United States)

Liberato, M. L. R.; Trigo, I. F.; Trigo, R. M.

2009-04-01

Extratropical cyclones, their dominant paths, frequency and intensity have long been the object of climatological studies. The analysis of cyclone characteristics for the Euro-Atlantic sector (85°W-70°E; 20°N-75°N) presented here is based on the cyclone detecting and tracking algorithm first developed for the Mediterranean region (Trigo et al., 1999, 2002) and recently extended to a larger Euro-Atlantic region (Trigo, 2006). The objective methodology, which identifies and follows individual lows (Trigo et al. 1999), is applied to 6-hourly geopotential data at 1000-hPa from two reanalyses datasets provided by the European Centre for Medium-Range Weather Forecasts (ECMWF): ERA-40 and ERA-Interim reanalyses. Two storm-track databases are built over the Northern Atlantic European area, spanning the common available extended winter seasons from October 1989 to March 2002. Although relatively short, this common period allows a comparison of systems represented in reanalyses datasets with distinct horizontal resolutions (T106 and T255, respectively). This exercise is mostly focused on the key areas of cyclone formation and dissipation and main cyclone characteristics for the Euro-Atlantic sector. Trigo, I. F., T. D. Davies, and G. R. Bigg, 1999: Objective climatology of cyclones in the Mediterranean region. J. Climate, 12, 1685-1696. Trigo I. F., G. R. Bigg and T. D. Davies, 2002: Climatology of Cyclogenesis Mechanisms in the Mediterranean. Mon. Weather Rev. 130, 549-569. Trigo, I. F. 2006: Climatology and Interannual Variability of Storm-Tracks in the Euro-Atlantic sector: a comparison between ERA-40 and NCEP/NCAR Reanalyses. Clim. Dyn. DOI 10.1007/s00382-005-0065-9.

Decentralized identification of nonlinear structure under strong ground motion using the extended Kalman filter and unscented Kalman filter

Science.gov (United States)

Tao, Dongwang; Li, Hui; Ma, Qiang

2016-04-01

Complete structure identification of complicate nonlinear system using extend Kalman filter (EKF) or unscented Kalman filter (UKF) may have the problems of divergence, huge computation and low estimation precision due to the large dimension of the extended state space for the system. In this article, a decentralized identification method of hysteretic system based on the joint EKF and UKF is proposed. The complete structure is divided into linear substructures and nonlinear substructures. The substructures are identified from the top to the bottom. For the linear substructure, EKF is used to identify the extended space including the displacements, velocities, stiffness and damping coefficients of the substructures, using the limited absolute accelerations and the identified interface force above the substructure. Similarly, for the nonlinear substructure, UKF is used to identify the extended space including the displacements, velocities, stiffness, damping coefficients and control parameters for the hysteretic Bouc-Wen model and the force at the interface of substructures. Finally a 10-story shear-type structure with multiple inter-story hysteresis is used for numerical simulation and is identified using the decentralized approach, and the identified results are compared with those using only EKF or UKF for the complete structure identification. The results show that the decentralized approach has the advantage of more stability, relative less computation and higher estimation precision.

Automatically detect and track infrared small targets with kernel Fukunaga-Koontz transform and Kalman prediction

Science.gov (United States)

Liu, Ruiming; Liu, Erqi; Yang, Jie; Zeng, Yong; Wang, Fanglin; Cao, Yuan

2007-11-01

Fukunaga-Koontz transform (FKT), stemming from principal component analysis (PCA), is used in many pattern recognition and image-processing fields. It cannot capture the higher-order statistical property of natural images, so its detection performance is not satisfying. PCA has been extended into kernel PCA in order to capture the higher-order statistics. However, thus far there have been no researchers who have definitely proposed kernel FKT (KFKT) and researched its detection performance. For accurately detecting potential small targets from infrared images, we first extend FKT into KFKT to capture the higher-order statistical properties of images. Then a framework based on Kalman prediction and KFKT, which can automatically detect and track small targets, is developed. Results of experiments show that KFKT outperforms FKT and the proposed framework is competent to automatically detect and track infrared point targets.

An Analysis of Operational Total Lightning Data During Long-Track Tornadoes

Science.gov (United States)

Carcione, Brian C.; Stano, Geoffrey T.

2012-01-01

The 27 April 2011 tornado outbreak brought three distinct waves of tornadic thunderstorms to portions of Mississippi, Alabama, Tennessee, and Georgia, striking the Tennessee Valley of north Alabama and southern Tennessee particularly hard. A total of 42 tornado paths were surveyed across the fourteen county area covered by the National Weather Service (NWS) forecast office in Huntsville, Alabama. Ten of these tornadoes were on the ground for at least 20 miles, two had total path lengths over 130 miles, and six tornadoes were classified as violent (EF-4 or EF-5 on the Enhanced Fujita Scale). Many of these tornadoes occurred within the domain of the North Alabama Lightning Mapping Array (NALMA), a ground-based total lightning detection network owned and operated by the NASA Marshall Space Flight Center. Since 2003, the NASA Short-term Prediction Research and Transition Center has supplied data from NALMA in real time to NWS forecast offices in Huntsville, Knoxville/Tri-Cities, Birmingham, and Nashville. Previous research has documented the utility of total lightning information in predicting tornadogenesis, particularly when combined with other remote sensing tools. Basic warning decision-making during events such as 27 April is not the most difficult part of the process; instead, the focus of warning meteorologists shifts to looking for changes in intensity or possible particularly dangerous situations, since doppler radar velocity data often cannot distinguish between weak and strong tornadoes. To that end, this research attempts to determine if any correlation exists between flash densities of the longest-tracked tornadoes over time, and the surveyed wind speeds of the tornadoes. The long-track EF-5 tornado which struck the Hackleburg, Phil Campbell, and Tanner communities in north Alabama was the primary focus of this research due to its intensity and extended life cycle. However, not all tornadoes were available for total lightning analysis due to widespread

Nuclear track-based biosensors with the enzyme laccase

Energy Technology Data Exchange (ETDEWEB)

García-Arellano, H. [Departamento de Ciencias Ambientales, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Lerma, Av. de las Garzas No. 10, Col. El Panteón, Lerma de Villada, Municipio de Lerma, Estado de México, C.P. 52005 (Mexico); Fink, D., E-mail: fink@xanum.uam.mx [Division de Ciencias Naturales e Ingeneria, Universidad Autónoma Metropolitana-Cuajimalpa, Artificios 40, Col. Hidalgo, Del. Álvaro Obregón C.P. 01120, México, D.F. (Mexico); Nuclear Physics Institute, 25068 Řež (Czech Republic); Muñoz Hernández, G. [Division de Ciencias Naturales e Ingeneria, Universidad Autónoma Metropolitana-Cuajimalpa, Artificios 40, Col. Hidalgo, Del. Álvaro Obregón C.P. 01120, México, D.F. (Mexico); Departamento de Fisica, Universidad Autónoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 México, D.F. (Mexico); Vacík, J.; Hnatowicz, V. [Nuclear Physics Institute, 25068 Řež (Czech Republic); Alfonta, L. [Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Ben-Gurion University of the Negev, PO Box 653, Beer-Sheva 84105 (Israel)

2014-08-15

Highlights: • We construct a biosensor using polymer foils with laccase-clad etched nuclear tracks. • We use the biosensor for quantitation of phenolic compounds. • The biosensor can detect picomolar concentrations for some phenolic compounds. - Abstract: A new type of biosensors for detecting phenolic compounds is presented here. These sensors consist of thin polymer foils with laccase-clad etched nuclear tracks. The presence of suitable phenolic compounds in the sensors leads to the formation of enzymatic reaction products in the tracks, which differ in their electrical conductivities from their precursor materials. These differences correlate with the concentrations of the phenolic compounds. Corresponding calibration curves have been established for a number of compounds. The sensors thus produced are capable to cover between 5 and 9 orders of magnitude in concentration – in the best case down to some picomoles. The sensor's detection sensitivity strongly depends on the specific compound. It is highest for caffeic acid and acid blue 74, followed by ABTS and ferulic acid.

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%

Modeling and simulation of protein elution in linear pH and salt gradients on weak, strong and mixed cation exchange resins applying an extended Donnan ion exchange model.

Science.gov (United States)

Wittkopp, Felix; Peeck, Lars; Hafner, Mathias; Frech, Christian

2018-04-13

Process development and characterization based on mathematic modeling provides several advantages and has been applied more frequently over the last few years. In this work, a Donnan equilibrium ion exchange (DIX) model is applied for modelling and simulation of ion exchange chromatography of a monoclonal antibody in linear chromatography. Four different cation exchange resin prototypes consisting of weak, strong and mixed ligands are characterized using pH and salt gradient elution experiments applying the extended DIX model. The modelling results are compared with the results using a classic stoichiometric displacement model. The Donnan equilibrium model is able to describe all four prototype resins while the stoichiometric displacement model fails for the weak and mixed weak/strong ligands. Finally, in silico chromatogram simulations of pH and pH/salt dual gradients are performed to verify the results and to show the consistency of the developed model. Copyright © 2018 Elsevier B.V. All rights reserved.

Robust online tracking via adaptive samples selection with saliency detection

Science.gov (United States)

Yan, Jia; Chen, Xi; Zhu, QiuPing

2013-12-01

Online tracking has shown to be successful in tracking of previously unknown objects. However, there are two important factors which lead to drift problem of online tracking, the one is how to select the exact labeled samples even when the target locations are inaccurate, and the other is how to handle the confusors which have similar features with the target. In this article, we propose a robust online tracking algorithm with adaptive samples selection based on saliency detection to overcome the drift problem. To deal with the problem of degrading the classifiers using mis-aligned samples, we introduce the saliency detection method to our tracking problem. Saliency maps and the strong classifiers are combined to extract the most correct positive samples. Our approach employs a simple yet saliency detection algorithm based on image spectral residual analysis. Furthermore, instead of using the random patches as the negative samples, we propose a reasonable selection criterion, in which both the saliency confidence and similarity are considered with the benefits that confusors in the surrounding background are incorporated into the classifiers update process before the drift occurs. The tracking task is formulated as a binary classification via online boosting framework. Experiment results in several challenging video sequences demonstrate the accuracy and stability of our tracker.

Kalman filter based data fusion for neutral axis tracking in wind turbine towers

DEFF Research Database (Denmark)

Soman, Rohan; Malinowski, Pawel; Ostachowicz, Wieslaw

2015-01-01

downtime, hence increasing the availability of the system. The present work is based on the use of neutral axis (NA) for SHM of the structure. The NA is tracked by data fusion of measured yaw angle and strain through the use of Extended Kalman Filter (EKF). The EKF allows accurate tracking even...... in the NA position may be used for detecting and locating the damage. The wind turbine tower has been modelled with FE software ABAQUS and validated on data from load measurements carried out on the 34m high tower of the Nordtank, NTK 500/41 wind turbine....

Strong cosmic censorship in de Sitter space

Science.gov (United States)

Dias, Oscar J. C.; Eperon, Felicity C.; Reall, Harvey S.; Santos, Jorge E.

2018-05-01

Recent work indicates that the strong cosmic censorship hypothesis is violated by nearly extremal Reissner-Nordström-de Sitter black holes. It was argued that perturbations of such a black hole decay sufficiently rapidly that the perturbed spacetime can be extended across the Cauchy horizon as a weak solution of the equations of motion. In this paper we consider the case of Kerr-de Sitter black holes. We find that, for any nonextremal value of the black hole parameters, there are quasinormal modes which decay sufficiently slowly to ensure that strong cosmic censorship is respected. Our analysis covers both scalar field and linearized gravitational perturbations.

Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals

Directory of Open Access Journals (Sweden)

Rafal Szlapczynski

2013-06-01

Full Text Available The paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction maneuvers, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behavior within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows how fitness function is designed to compare various possible tracks as well as to assess the quality of a final solution. The impact of the fitness function on the method’s results is illustrated by examples.

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.

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

COMPARISON OF RECURSIVE ESTIMATION TECHNIQUES FOR POSITION TRACKING RADIOACTIVE SOURCES

International Nuclear Information System (INIS)

Muske, K.; Howse, J.

2000-01-01

This paper compares the performance of recursive state estimation techniques for tracking the physical location of a radioactive source within a room based on radiation measurements obtained from a series of detectors at fixed locations. Specifically, the extended Kalman filter, algebraic observer, and nonlinear least squares techniques are investigated. The results of this study indicate that recursive least squares estimation significantly outperforms the other techniques due to the severe model nonlinearity

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 with the Hough transformation for the central drift chamber of the GSI 4πexperiment

International Nuclear Information System (INIS)

Best, D.

1993-02-01

The adaptive Hough Transformation (AHT) treated in this thesis is a method to localize the peaks in the Hough field without calculating the background in detail. It applies an intelligent histogram and search strategy. It uses a small accumulator and decomposes the parameter region, which is momentaneously of interest, into few intervals, into which the HT maps the hits. The information in the accumulator is then used to redefine the parameter region, so that interesting regions can be studied with higher resolution. The iteration continues, until the parameters are determined with the wanted resolution. In the mean 4-7 iterations are necessary in order to obtain the center coordinates of a circular track up to 1 mm accurately. It was shown that the AHT extends the tracking possibilities to very high track densities. The time consumation for 100 tracks with track and vertex fitting lies in the range of 4-5 seconds. By this method in comparison to local procedures in this region of track multiplicities is be proved as superior, because it is not confronted with combinatorical difficulties. Thereby the track and point removal efficiency remains at above 95%, and the double-track resolution at 1%. The dominant majority of the particle tracks is almost completely reconstructed. (orig./HSI) [de

Framework to parameterize and validate APEX to support deployment of the nutrient tracking tool

Science.gov (United States)

Guidelines have been developed to parameterize and validate the Agricultural Policy Environmental eXtender (APEX) to support the Nutrient Tracking Tool (NTT). This follow-up paper presents 1) a case study to illustrate how the developed guidelines are applied in a headwater watershed located in cent...

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.

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...

3D head pose estimation and tracking using particle filtering and ICP algorithm

KAUST Repository

Ben Ghorbel, Mahdi; Baklouti, Malek; Couvet, Serge

2010-01-01

This paper addresses the issue of 3D head pose estimation and tracking. Existing approaches generally need huge database, training procedure, manual initialization or use face feature extraction manually extracted. We propose a framework for estimating the 3D head pose in its fine level and tracking it continuously across multiple Degrees of Freedom (DOF) based on ICP and particle filtering. We propose to approach the problem, using 3D computational techniques, by aligning a face model to the 3D dense estimation computed by a stereo vision method, and propose a particle filter algorithm to refine and track the posteriori estimate of the position of the face. This work comes with two contributions: the first concerns the alignment part where we propose an extended ICP algorithm using an anisotropic scale transformation. The second contribution concerns the tracking part. We propose the use of the particle filtering algorithm and propose to constrain the search space using ICP algorithm in the propagation step. The results show that the system is able to fit and track the head properly, and keeps accurate the results on new individuals without a manual adaptation or training. © Springer-Verlag Berlin Heidelberg 2010.

Extended Hubbard models for ultracold atoms in optical lattices

International Nuclear Information System (INIS)

Juergensen, Ole

2015-01-01

In this thesis, the phase diagrams and dynamics of various extended Hubbard models for ultracold atoms in optical lattices are studied. Hubbard models are the primary description for many interacting particles in periodic potentials with the paramount example of the electrons in solids. The very same models describe the behavior of ultracold quantum gases trapped in the periodic potentials generated by interfering beams of laser light. These optical lattices provide an unprecedented access to the fundamentals of the many-particle physics that govern the properties of solid-state materials. They can be used to simulate solid-state systems and validate the approximations and simplifications made in theoretical models. This thesis revisits the numerous approximations underlying the standard Hubbard models with special regard to optical lattice experiments. The incorporation of the interaction between particles on adjacent lattice sites leads to extended Hubbard models. Offsite interactions have a strong influence on the phase boundaries and can give rise to novel correlated quantum phases. The extended models are studied with the numerical methods of exact diagonalization and time evolution, a cluster Gutzwiller approximation, as well as with the strong-coupling expansion approach. In total, this thesis demonstrates the high relevance of beyond-Hubbard processes for ultracold atoms in optical lattices. Extended Hubbard models can be employed to tackle unexplained problems of solid-state physics as well as enter previously inaccessible regimes.

Extended Hubbard models for ultracold atoms in optical lattices

Energy Technology Data Exchange (ETDEWEB)

Juergensen, Ole

2015-06-05

In this thesis, the phase diagrams and dynamics of various extended Hubbard models for ultracold atoms in optical lattices are studied. Hubbard models are the primary description for many interacting particles in periodic potentials with the paramount example of the electrons in solids. The very same models describe the behavior of ultracold quantum gases trapped in the periodic potentials generated by interfering beams of laser light. These optical lattices provide an unprecedented access to the fundamentals of the many-particle physics that govern the properties of solid-state materials. They can be used to simulate solid-state systems and validate the approximations and simplifications made in theoretical models. This thesis revisits the numerous approximations underlying the standard Hubbard models with special regard to optical lattice experiments. The incorporation of the interaction between particles on adjacent lattice sites leads to extended Hubbard models. Offsite interactions have a strong influence on the phase boundaries and can give rise to novel correlated quantum phases. The extended models are studied with the numerical methods of exact diagonalization and time evolution, a cluster Gutzwiller approximation, as well as with the strong-coupling expansion approach. In total, this thesis demonstrates the high relevance of beyond-Hubbard processes for ultracold atoms in optical lattices. Extended Hubbard models can be employed to tackle unexplained problems of solid-state physics as well as enter previously inaccessible regimes.

Game theory-based visual tracking approach focusing on color and texture features.

Science.gov (United States)

Jin, Zefenfen; Hou, Zhiqiang; Yu, Wangsheng; Chen, Chuanhua; Wang, Xin

2017-07-20

It is difficult for a single-feature tracking algorithm to achieve strong robustness under a complex environment. To solve this problem, we proposed a multifeature fusion tracking algorithm that is based on game theory. By focusing on color and texture features as two gamers, this algorithm accomplishes tracking by using a mean shift iterative formula to search for the Nash equilibrium of the game. The contribution of different features is always keeping the state of optical balance, so that the algorithm can fully take advantage of feature fusion. According to the experiment results, this algorithm proves to possess good performance, especially under the condition of scene variation, target occlusion, and similar interference.

Heavy axions from strong broken horizontal gauge symmetry

International Nuclear Information System (INIS)

Elliott, T.; King, S.F.

1993-01-01

We study the consequences of the existence and breaking of a Peccei-Quinn symmetry within the context of a dynamical model of electroweak symmetry breaking based on broken gauged flavour symmetries. We perform an estimate of the axion mass by including flavour instanton effects and show that, for low cut-offs, the axion is sufficiently massive to prevent it from being phenomenologically unacceptable. We conclude with an examination of the strong CP problem and show that our axion cannot solve the problem, though we indicate ways in which the model can be extended so that the strong CP problem is solved. (orig.)

Robustness-tracking control based on sliding mode and H∞ theory for linear servo system

Institute of Scientific and Technical Information of China (English)

TIAN Yan-feng; GUO Qing-ding

2005-01-01

A robustness-tracking control scheme based on combining H∞ robust control and sliding mode control is proposed for a direct drive AC permanent-magnet linear motor servo system to solve the conflict between tracking and robustness of the linear servo system. The sliding mode tracking controller is designed to ensure the system has a fast tracking characteristic to the command, and the H∞ robustness controller suppresses the disturbances well within the close loop( including the load and the end effect force of linear motor etc. ) and effectively minimizes the chattering of sliding mode control which influences the steady state performance of the system. Simulation results show that this control scheme enhances the track-command-ability and the robustness of the linear servo system, and in addition, it has a strong robustness to parameter variations and resistance disturbances.

Accuracy Improvement of Real-Time Location Tracking for Construction Workers

Directory of Open Access Journals (Sweden)

Hyunsoo Kim

2018-05-01

Full Text Available Extensive research has been conducted on the real-time locating system (RTLS for tracking construction components, including workers, equipment, and materials, in order to improve construction performance (e.g., productivity improvement or accident prevention. In order to prevent safety accidents and make more sustainable construction job sites, the higher accuracy of RTLS is required. To improve the accuracy of RTLS in construction projects, this paper presents a RTLS using radio frequency identification (RFID. For this goal, this paper develops a location tracking error mitigation algorithm and presents the concept of using assistant tags. The applicability and effectiveness of the developed RTLS are tested under eight different construction environments and the test results confirm the system’s strong potential for improving the accuracy of real-time location tracking in construction projects, thus enhancing construction performance.

[Study on method of tracking the active cells in image sequences based on EKF-PF].

Science.gov (United States)

Tang, Chunming; Liu, Ying

2013-02-01

In cell image sequences, due to the nonlinear and nonGaussian motion characteristics of active cells, the accurate prediction and tracking is still an unsolved problem. We applied extended Kalman particle filter (EKF-PF) here in our study, attempting to solve the problem. Firstly we confirmed the existence and positions of the active cells. Then we established a motion model and improved it via adding motion angle estimation. Next we predicted motion parameters, such as displacement, velocity, accelerated velocity and motion angle, in region centers of the cells being tracked. Finally we obtained the motion traces of active cells. There were fourteen active cells in three image sequences which have been tracked. The errors were less than 2.5 pixels when the prediction values were compared with actual values. It showed that the presented algorithm may basically reach the solution of accurate predition and tracking of the active cells.

The response of CR-39 nuclear track detector to 1-9 MeV protons

International Nuclear Information System (INIS)

Sinenian, N.; Rosenberg, M. J.; Manuel, M.; McDuffee, S. C.; Casey, D. T.; Zylstra, A. B.; Rinderknecht, H. G.; Gatu Johnson, M.; Seguin, F. H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.

2011-01-01

The response of CR-39 nuclear track detector (TasTrak) to protons in the energy range of 0.92-9.28 MeV has been studied. Previous studies of the CR-39 response to protons have been extended by examining the piece-to-piece variability in addition to the effects of etch time and etchant temperature; it is shown that the shape of the CR-39 response curve to protons can vary from piece-to-piece. Effects due to the age of CR-39 have also been studied using 5.5 MeV alpha particles over a 5-year period. Track diameters were found to degrade with the age of the CR-39 itself rather than the age of the tracks, consistent with previous studies utilizing different CR-39 over shorter time periods.

Orbits in weak and strong bars

CERN Document Server

Contopoulos, George

1980-01-01

The authors study the plane orbits in simple bar models embedded in an axisymmetric background when the bar density is about 1% (weak), 10% (intermediate) or 100% (strong bar) of the axisymmetric density. Most orbits follow the stable periodic orbits. The basic families of periodic orbits are described. In weak bars with two Inner Lindblad Resonances there is a family of stable orbits extending from the center up to the Outer Lindblad Resonance. This family contains the long period orbits near corotation. Other stable families appear between the Inner Lindblad Resonances, outside the Outer Lindblad Resonance, around corotation (short period orbits) and around the center (retrograde). Some families become unstable or disappear in strong bars. A comparison is made with cases having one or no Inner Lindblad Resonance. (12 refs).

Beyond Group: Multiple Person Tracking via Minimal Topology-Energy-Variation.

Science.gov (United States)

Gao, Shan; Ye, Qixiang; Xing, Junliang; Kuijper, Arjan; Han, Zhenjun; Jiao, Jianbin; Ji, Xiangyang

2017-12-01

Tracking multiple persons is a challenging task when persons move in groups and occlude each other. Existing group-based methods have extensively investigated how to make group division more accurately in a tracking-by-detection framework; however, few of them quantify the group dynamics from the perspective of targets' spatial topology or consider the group in a dynamic view. Inspired by the sociological properties of pedestrians, we propose a novel socio-topology model with a topology-energy function to factor the group dynamics of moving persons and groups. In this model, minimizing the topology-energy-variance in a two-level energy form is expected to produce smooth topology transitions, stable group tracking, and accurate target association. To search for the strong minimum in energy variation, we design the discrete group-tracklet jump moves embedded in the gradient descent method, which ensures that the moves reduce the energy variation of group and trajectory alternately in the varying topology dimension. Experimental results on both RGB and RGB-D data sets show the superiority of our proposed model for multiple person tracking in crowd scenes.

Initial uncertainty in Pavlovian reward prediction persistently elevates incentive salience and extends sign-tracking to normally unattractive cues.

Science.gov (United States)

Robinson, Mike J F; Anselme, Patrick; Fischer, Adam M; Berridge, Kent C

2014-06-01

Uncertainty is a component of many gambling games and may play a role in incentive motivation and cue attraction. Uncertainty can increase the attractiveness for predictors of reward in the Pavlovian procedure of autoshaping, visible as enhanced sign-tracking (or approach and nibbles) by rats of a metal lever whose sudden appearance acts as a conditioned stimulus (CS+) to predict sucrose pellets as an unconditioned stimulus (UCS). Here we examined how reward uncertainty might enhance incentive salience as sign-tracking both in intensity and by broadening the range of attractive CS+s. We also examined whether initially induced uncertainty enhancements of CS+ attraction can endure beyond uncertainty itself, and persist even when Pavlovian prediction becomes 100% certain. Our results show that uncertainty can broaden incentive salience attribution to make CS cues attractive that would otherwise not be (either because they are too distal from reward or too risky to normally attract sign-tracking). In addition, uncertainty enhancement of CS+ incentive salience, once induced by initial exposure, persisted even when Pavlovian CS-UCS correlations later rose toward 100% certainty in prediction. Persistence suggests an enduring incentive motivation enhancement potentially relevant to gambling, which in some ways resembles incentive-sensitization. Higher motivation to uncertain CS+s leads to more potent attraction to these cues when they predict the delivery of uncertain rewards. In humans, those cues might possibly include the sights and sounds associated with gambling, which contribute a major component of the play immersion experienced by problematic gamblers. Copyright © 2014 Elsevier B.V. All rights reserved.

Synoptic Scale North American Weather Tracks and the Formation of North Atlantic Windstorms

Science.gov (United States)

Baum, A. J.; Godek, M. L.

2014-12-01

Each winter, dozens of fatalities occur when intense North Atlantic windstorms impact Western Europe. Forecasting the tracks of these storms in the short term is often problematic, but long term forecasts provide an even greater challenge. Improved prediction necessitates the ability to identify these low pressure areas at formation and understand commonalities that distinguish these storms from other systems crossing the Atlantic, such as where they develop. There is some evidence that indicates the majority of intense windstorms that reach Europe have origins far west, as low pressure systems that develop over the North American continent. This project aims to identify the specific cyclogenesis regions in North America that produce a significantly greater number of dangerous storms. NOAA Ocean Prediction Center surface pressure reanalysis maps are used to examine the tracks of storms. Strong windstorms are characterized by those with a central pressure of less than 965 hPa at any point in their life cycle. Tracks are recorded using a coding system based on source region, storm track and dissipation region. The codes are analyzed to determine which region contains the most statistical significance with respect to strong Atlantic windstorm generation. The resultant set of codes also serves as a climatology of North Atlantic extratropical cyclones. Results indicate that a number of windstorms favor cyclogenesis regions off the east coast of the United States. A large number of strong storms that encounter east coast cyclogenesis zones originate in the central mountain region, around Colorado. These storms follow a path that exits North America around New England and subsequently travel along the Canadian coast. Some of these are then primed to become "bombs" over the open Atlantic Ocean.

Longitudinal tracking studies for a high intensity proton synchrotron

International Nuclear Information System (INIS)

Lessner, E.; Cho, Y.; Harkay, K.; Symon, K.

1995-01-01

Results from longitudinal tracking studies for a high intensity proton synchrotron designed for a 1-MW spallation source are presented. The machine delivers a proton beam of 0.5 mA time-averaged current at a repetition rate of 30 Hz. The accelerator is designed to have radiation levels that allow hands-on-maintenance. However, the high beam intensity causes strong space charge fields whose effects may lead to particle loss and longitudinal instabilities. The space charge fields modify the particle distribution, distort the stable bucket area and reduce the rf linear restoring force. Tracking simulations were conducted to analyze the space charge effects on the dynamics of the injection and acceleration processes and means to circumvent them. The tracking studies led to the establishment of the injected beam parameters and rf voltage program that minimized beam loss and longitudinal instabilities. Similar studies for a 10-GeV synchrotron that uses the 2-GeV synchrotron as its injector are also discussed

Successful talent development in track and field

DEFF Research Database (Denmark)

Henriksen, K; Stambulova, N; Roessler, K K

2010-01-01

Track and field includes a number of high-intensity disciplines with many demanding practices and represents a motivational challenge for talented athletes aiming to make a successful transition to the senior elite level. Based on a holistic ecological approach, this study presents an analysis...... of a particular athletic talent development environment, the IFK Växjö track and field club, and examines key factors behind its successful history of creating top-level athletes. The research takes the form of a case study. Data were collected from multiple perspectives (in-depth interviews with administrators...... to elite athletes. A strong organizational culture, characterized by values of open co-operation, by a focus on performance process and by a whole-person approach, provided an important basis for the environment's success. The holistic ecological approach encourages practitioners to broaden their focus...

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.

Using music structure to improve beat tracking

Science.gov (United States)

Dannenberg, Roger B.

2005-09-01

Beats are an important feature of most music. Beats are used in music information retrieval systems for genre classification, similarity search, and segmentation. However, beats can be difficult to identify, especially in music audio. Traditional beat trackers attempt to (1) match predicted beats to observations of likely beats, and (2) maintain a fairly steady tempo. A third criterion can be added: when repetitions of musical passages occur, the beats in the first repetition should align with the beats in all other repetitions. This third criterion improves beat tracking performance significantly. Repetitions of musical passages are discovered in audio data by searching for similar sequences of chroma vectors. Beats are ``tracked'' by first locating a sequence of likely beats in the music audio using high frequency energy as an indicator of beat likelihood. This beat sequence is then extended by searching forward and backward for more matching beats, allowing slight variations in tempo, and using a relaxation algorithm to optimize the proposed beat locations with respect to the three criteria. Other high-level music features may offer further improvements in beat identification.

JACoW Accelerator fault tracking at CERN

CERN Document Server

Roderick, Chris; Martin Anido, Daniel; Pade, Steffen; Wilk, Pawel

2018-01-01

CERN’s Accelerator Fault Tracking (AFT) system aims to facilitate answering questions like: “Why are we not doing physics when we should be?” and “What can we do to increase machine availability?” People have tracked faults for many years, using numerous, diverse, distributed and un-related systems. As a result, and despite a lot of effort, it has been difficult to get a clear and consistent overview of what is going on, where the problems are, how long they last for, and what is the impact. This is particularly true for the LHC, where faults may induce long recovery times after being fixed. The AFT project was launched in February 2014 as a collaboration between the Controls and Operations groups with stakeholders from the LHC Availability Working Group (AWG). The AFT system has been used successfully in operation for LHC since 2015, yielding a lot of interest and generating a growing user community. In 2017 the scope has been extended to cover the entire Injector Complex. This paper will describe ...

Storm-tracks interannual variability and large-scale climate modes

Science.gov (United States)

Liberato, Margarida L. R.; Trigo, Isabel F.; Trigo, Ricardo M.

2013-04-01

In this study we focus on the interannual variability and observed changes in northern hemisphere mid-latitude storm-tracks and relate them to large scale atmospheric circulation variability modes. Extratropical storminess, cyclones dominant paths, frequency and intensity have long been the object of climatological studies. The analysis of storm characteristics and historical trends presented here is based on the cyclone detecting and tracking algorithm first developed for the Mediterranean region (Trigo et al. 1999) and recently extended to a larger Euro-Atlantic region (Trigo 2006). The objective methodology, which identifies and follows individual lows as minima in SLP fields, fulfilling a set of conditions regarding the central pressure and the pressure gradient, is applied to the northern hemisphere 6-hourly geopotential data at 1000 hPa from the 20th Century Reanalyses (20CRv2) project and from reanalyses datasets provided by the European Centre for Medium-Range Weather Forecasts (ECMWF): ERA-40 and ERA Interim reanalyses. First, we assess the interannual variability and cyclone frequency trends for each of the datasets, for the 20th century and for the period between 1958 and 2002 using the highest spatial resolution available (1.125° x 1.125°) from the ERA-40 data. Results show that winter variability of storm paths, cyclone frequency and travel times is in agreement with the reported variability in a number of large-scale climate patterns (including the North Atlantic Oscillation, the East Atlantic Pattern and the Scandinavian Pattern). In addition, three storm-track databases are built spanning the common available extended winter seasons from October 1979 to March 2002. Although relatively short, this common period allows a comparison of systems represented in reanalyses datasets with distinct horizontal resolutions. This exercise is mostly focused on the key areas of cyclogenesis and cyclolysis and main cyclone characteristics over the northern

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.

Shifting Pacific storm tracks as stressors to ecosystems of western North America.

Science.gov (United States)

Dannenberg, Matthew P; Wise, Erika K

2017-11-01

Much of the precipitation delivered to western North America arrives during the cool season via midlatitude Pacific storm tracks, which may experience future shifts in response to climate change. Here, we assess the sensitivity of the hydroclimate and ecosystems of western North America to the latitudinal position of cool-season Pacific storm tracks. We calculated correlations between storm track variability and three hydroclimatic variables: gridded cool-season standardized precipitation-evapotranspiration index, April snow water equivalent, and water year streamflow from a network of USGS stream gauges. To assess how historical storm track variability affected ecosystem processes, we derived forest growth estimates from a large network of tree-ring widths and land surface phenology and wildfire estimates from remote sensing. From 1980 to 2014, cool-season storm tracks entered western North America between approximately 41°N and 53°N. Cool-season moisture supply and snowpack responded strongly to storm track position, with positive correlations to storm track latitude in eastern Alaska and northwestern Canada but negative correlations in the northwestern U.S. Ecosystems of the western United States were greener and more productive following winters with south-shifted storm tracks, while Canadian ecosystems were greener in years when the cool-season storm track was shifted to the north. On average, larger areas of the northwestern United States were burned by moderate to high severity wildfires when storm tracks were displaced north, and the average burn area per fire also tended to be higher in years with north-shifted storm tracks. These results suggest that projected shifts of Pacific storm tracks over the 21st century would likely alter hydroclimatic and ecological regimes in western North America, particularly in the northwestern United States, where moisture supply and ecosystem processes are highly sensitive to the position of cool-season storm tracks. �

Requirements for the Silicon Tracking System of CBM at FAIR

International Nuclear Information System (INIS)

Heuser, Johann M.; Deveaux, M.; Muentz, C.; Stroth, J.

2006-01-01

The Compressed Baryonic Matter (CBM) experiment at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt will systematically study dense baryonic matter created in collisions of intense heavy-ion beams with nuclear targets. The research addresses current questions of strong-interaction physics as confinement in normal nuclear matter, chiral symmetry restoration in deconfined matter at high temperatures and densities, and the search for the critical end-point of the phase boundary. With beams of ions as heavy as Au and U, energies up to 45GeV/nucleon and intensities up to 10 12 ions per pulse, FAIR will enable CBM to probe the phase diagram of quantum chromo dynamics (QCD) in a region poorly known, while being complementary to current and future research programmes at RHIC and LHC. The CBM experiment is planned as a fixed-target spectrometer optimized for the detection of rare probes. Among these are open charm and low-mass vector mesons, important observables for the initial energetic and dense phase of the collisions. The experimental concept and challenge is to accomplish charged particle tracking in the high-multiplicity, high-radiation collision environment. This will be realized exclusively with a silicon tracking detector system installed in a strong magnetic dipole field directly behind the target. Key to the physics of CBM and benchmark for the tracking is the reconstruction of short-lived charmed mesons that puts high demands on the silicon detectors. The article presents a conceptual design of the CBM experiment with emphasis on the silicon tracking system. Requirements for silicon microstrip and pixel detectors and their arrangement in the tracker are discussed in relation to important physics observables addressed by CBM

Fast neutron dosimetry using CR-39 track detectors with polyethylene as radiator

International Nuclear Information System (INIS)

Castillo, F.; Espinosa, G.; Golzarri, J.I.; Osorio, D.; Rangel, J.; Reyes, P.G.; Herrera, J.J.E.

2013-01-01

The chemical etching parameters (etching time, temperature, normality of etchant, etc.) for the use of CR-39 (allyl diglycol carbonate – Lantrack ® ) as a fast neutron dosimeter have been optimized. The CR-39 chips, placed under a 1.5 mm polyethylene radiator, were exposed for calibration to an 241 Am-Be source at different time intervals for a given neutron fluence. After several chemical etching processes of the detectors with different conditions, the optimum characteristics for the chemical etching were found at 6N KOH solution, 60 ± 1 °C, for 12 h. An accurate relationship between the dose and fluence calculations was obtained as a function of the track density. - Highlights: ► Optimum etching time for fast neutron irradiated CR-39 track detectors is found. ► Relationship between dose and fluence obtained as a function of the track density. ► Results are consistent with those reported elsewhere, and extend the dose range

Propagation of strong electromagnetic beams in inhomogeneous plasmas

Energy Technology Data Exchange (ETDEWEB)

Ferrari, A; Massaglia, S [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Ist. di Fisica Generale)

1980-09-01

We study some simple aspects of nonlinear propagation of relativistically strong electromagnetic beams in inhomogeneous plasmas, especially in connection with effects of beam self-trapping in extended extragalactic radio sources. The two effects of (i) long scale longitudinal and radial inhomogeneities inherent to the plasma and (ii) radial inhomogeneities produced by the ponderomotive force of the beam itself are investigated.

A Deep-Structured Conditional Random Field Model for Object Silhouette Tracking.

Directory of Open Access Journals (Sweden)

Mohammad Javad Shafiee

Full Text Available In this work, we introduce a deep-structured conditional random field (DS-CRF model for the purpose of state-based object silhouette tracking. The proposed DS-CRF model consists of a series of state layers, where each state layer spatially characterizes the object silhouette at a particular point in time. The interactions between adjacent state layers are established by inter-layer connectivity dynamically determined based on inter-frame optical flow. By incorporate both spatial and temporal context in a dynamic fashion within such a deep-structured probabilistic graphical model, the proposed DS-CRF model allows us to develop a framework that can accurately and efficiently track object silhouettes that can change greatly over time, as well as under different situations such as occlusion and multiple targets within the scene. Experiment results using video surveillance datasets containing different scenarios such as occlusion and multiple targets showed that the proposed DS-CRF approach provides strong object silhouette tracking performance when compared to baseline methods such as mean-shift tracking, as well as state-of-the-art methods such as context tracking and boosted particle filtering.

Muon track induced current measurements in semi-insulating GaAs

Energy Technology Data Exchange (ETDEWEB)

Eshchenko, D.G., E-mail: dimitry.eshchenko@psi.c [Physik-Institut der Universitaet Zuerich, CH-8057 Zuerich (Switzerland); Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen (Switzerland); Storchak, V.G. [Russian Research Centre ' Kurchatov Institute' , Kurchatov Sq. 1, Moscow 123182 (Russian Federation); Cottrell, S.P. [ISIS Facility, Rutherford Appleton Laboratory, Oxfordshire OX11 OQX (United Kingdom)

2009-04-15

We report on preliminary muon-track-induced current measurements in semi-insulating (SI-) GaAs. At T=70K, after simultaneous treatment of the sample by muon irradiation and a strong electric field (a square wave with |E|>10kV/cm and the polarity changed every 1/(50) s) for approximately 2 h, the sample is transferred to a metastable-like state which is characterized by increased life-times for non-equilibrium electrons and holes. The sample can be returned to the original state by heating up to 250 K. Our results for SI-GaAs suggest a muon-track-induced electric-field-assisted neutralization process for the deep traps.

Sliding mode based trajectory linearization control for hypersonic reentry vehicle via extended disturbance observer.

Science.gov (United States)

Xingling, Shao; Honglun, Wang

2014-11-01

This paper proposes a novel hybrid control framework by combing observer-based sliding mode control (SMC) with trajectory linearization control (TLC) for hypersonic reentry vehicle (HRV) attitude tracking problem. First, fewer control consumption is achieved using nonlinear tracking differentiator (TD) in the attitude loop. Second, a novel SMC that employs extended disturbance observer (EDO) to counteract the effect of uncertainties using a new sliding surface which includes the estimation error is integrated to address the tracking error stabilization issues in the attitude and angular rate loop, respectively. In addition, new results associated with EDO are examined in terms of dynamic response and noise-tolerant performance, as well as estimation accuracy. The key feature of the proposed compound control approach is that chattering free tracking performance with high accuracy can be ensured for HRV in the presence of multiple uncertainties under control constraints. Based on finite time convergence stability theory, the stability of the resulting closed-loop system is well established. Also, comparisons and extensive simulation results are presented to demonstrate the effectiveness of the control strategy. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

A STRONGLY COUPLED REACTOR CORE ISOLATION COOLING SYSTEM MODEL FOR EXTENDED STATION BLACK-OUT ANALYSES

Energy Technology Data Exchange (ETDEWEB)

Zhao, Haihua [Idaho National Laboratory; Zhang, Hongbin [Idaho National Laboratory; Zou, Ling [Idaho National Laboratory; Martineau, Richard Charles [Idaho National Laboratory

2015-03-01

The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup cooling water to the reactor pressure vessel (RPV) when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. The RCIC system operates independently of AC power, service air, or external cooling water systems. The only required external energy source is from the battery to maintain the logic circuits to control the opening and/or closure of valves in the RCIC systems in order to control the RPV water level by shutting down the RCIC pump to avoid overfilling the RPV and flooding the steam line to the RCIC turbine. It is generally considered in almost all the existing station black-out accidents (SBO) analyses that loss of the DC power would result in overfilling the steam line and allowing liquid water to flow into the RCIC turbine, where it is assumed that the turbine would then be disabled. This behavior, however, was not observed in the Fukushima Daiichi accidents, where the Unit 2 RCIC functioned without DC power for nearly three days. Therefore, more detailed mechanistic models for RCIC system components are needed to understand the extended SBO for BWRs. As part of the effort to develop the next generation reactor system safety analysis code RELAP-7, we have developed a strongly coupled RCIC system model, which consists of a turbine model, a pump model, a check valve model, a wet well model, and their coupling models. Unlike the traditional SBO simulations where mass flow rates are typically given in the input file through time dependent functions, the real mass flow rates through the turbine and the pump loops in our model are dynamically calculated according to conservation laws and turbine/pump operation curves. A simplified SBO demonstration RELAP-7 model with this RCIC model has been successfully developed. The demonstration model includes the major components for the primary system of a BWR, as well as the safety

Conductivity enhancement of ion tracks in tetrahedral amorphous carbon by doping with N, B, Cu and Fe

International Nuclear Information System (INIS)

Krauser, J.; Nix, A.-K.; Gehrke, H.-G.; Hofsäss, H.; Trautmann, C.; Weidinger, A.

2012-01-01

Conducting ion tracks are formed when high-energy heavy ions (e.g. 1 GeV Au) pass through tetrahedral amorphous carbon (ta-C). These nanowires with a diameter of about 8 nm are embedded in the insulating ta-C matrix and of interest for various nanotechnological applications. Usually the overall conductivity of the tracks and the current/voltage characteristics (Ohmic or non-Ohmic) vary strongly from track to track, even when measured on the same sample, indicating that the track formation is neither complete nor homogeneous. To improve the track conductivity, doping of ta-C with N, B, Cu, or Fe is investigated. Beneficial changes in track conductivity after doping compete with a conductivity increase of the surrounding matrix material. Best results are achieved by incorporation of 1 at.% Cu, while for different reasons, the improvement of the tracks remains moderate for N, B, and Fe doping. Conductivity enhancement of the tracks is assumed to develop during the ion track formation process by an increased number of localized states which contribute to the current transport.

Fuzzy Vector Field Orientation Feedback Control-Based Slip Compensation for Trajectory Tracking Control of a Four Track Wheel Skid-steered Mobile Robot

Directory of Open Access Journals (Sweden)

Xuan Vinh Ha

2013-04-01

Full Text Available Skid-steered mobile robots have been widely used in exploring unknown environments and in military applications. In this paper, the tuning fuzzy Vector Field Orientation (FVFO feedback control method is proposed for a four track wheel skid-steered mobile robot (4-TW SSMR using flexible fuzzy logic control (FLC. The extended Kalman filter is utilized to estimate the positions, velocities and orientation angles, which are used for feedback control signals in the FVFO method, based on the AHRS kinematic motion model and velocity constraints. In addition, in light of the wheel slip and the braking ability of the robot, we propose a new method for estimating online wheel slip parameters based on a discrete Kalman filter to compensate for the velocity constraints. As demonstrated by our experimental results, the advantages of the combination of the proposed FVFO and wheel slip estimation methods overcome the limitations of the others in the trajectory tracking control problem for a 4-TW SSMR.

Luminescent tracks of high-energy photoemitted electrons accelerated by plasmonic fields

Directory of Open Access Journals (Sweden)

Di Vece Marcel

2015-12-01

Full Text Available The emission of an electron from a metal nanostructure under illumination and its subsequent acceleration in a plasmonic field forms a platform to extend these phenomena to deposited nanoparticles, which can be studied by state-of-the-art confocal microscopy combined with femtosecond optical excitation. The emitted and accelerated electrons leave defect tracks in the immersion oil, which can be revealed by thermoluminescence. These photographic tracks are read out with the confocal microscope and have a maximum length of about 80 μm, which corresponds to a kinetic energy of about 100 keV. This energy is consistent with the energy provided by the intense laser pulse combined with plasmonic local field enhancement. The results are discussed within the context of the rescattering model by which electrons acquire more energy. The visualization of electron tracks originating from plasmonic field enhancement around a gold nanoparticle opens a new way to study with confocal microscopy both the plasmonic properties of metal nano objects as well as high energy electron interaction with matter.

Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

Energy Technology Data Exchange (ETDEWEB)

Viel, Simon, E-mail: sviel@lbl.gov [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Banerjee, Swagato [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Pranko, Aliaksandr [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Rieger, Julia [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); II Physikalisches Institut, Georg-August-Universität, Göttingen (Germany); Wolf, Julian [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Wu, Sau Lan; Yang, Hongtao [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States)

2016-09-21

In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN. - Highlights: • Extended inner pixel barrel layers are proposed for the ATLAS ITk upgrade. • Test beam results at small track incidence angles validate this ATLAS ITk design. • Long pixel clusters are reconstructed with high efficiency at low threshold values. • Excellent angular resolution is achieved using pixel cluster length information.

Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

International Nuclear Information System (INIS)

Viel, Simon; Banerjee, Swagato; Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice; Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar; Pranko, Aliaksandr; Rieger, Julia; Wolf, Julian; Wu, Sau Lan; Yang, Hongtao

2016-01-01

In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN. - Highlights: • Extended inner pixel barrel layers are proposed for the ATLAS ITk upgrade. • Test beam results at small track incidence angles validate this ATLAS ITk design. • Long pixel clusters are reconstructed with high efficiency at low threshold values. • Excellent angular resolution is achieved using pixel cluster length information.

GRGM900C: A Degree 900 Lunar Gravity Model from GRAIL Primary and Extended Mission Data

Science.gov (United States)

Lemoine, Frank G.; Goossens, Sander; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Bryant, D. Loomis; Chinn, Douglas S.; Neumann, Gregory A.; Smith, David E.;

A simplified Track Assembler I/O for the Muon Trigger Track Finder

CERN Document Server

Dallavalle, Gaetano-Marco; Genchev, Vladimir; Grandi, Claudio; Neumeister, Norbert; Porth, Paul; Rohringer, Herbert

1998-01-01

One of the architectural concerns in the present design of the Muon Trigger Track Finder ( MTTF) is the large number of inputs to the Track Assembler ( TA). In the TA block, input track segment pairs from many Extrapolation Units ( EU) are associated into tracks. The relative contribution of these inputs to the assembled tracks is studied with simulated track patterns for low and high pt muons over the entire eta, phi acceptance of the CMS barrel. A pruning of the EUs is proposed which does not alter the performance of the Track Finder and minimizes the interconnections between azimuthal wedges.

Solar tracking system

Science.gov (United States)

Okandan, Murat; Nielson, Gregory N.

2016-07-12

Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

Radial oscillations of neutron stars in strong magnetic fields

Indian Academy of Sciences (India)

The eigen frequencies of radial pulsations of neutron stars are calculated in a strong magnetic field. At low densities we use the magnetic BPS equation of state (EOS) similar to that obtained by Lai and Shapiro while at high densities the EOS obtained from the relativistic nuclear mean field theory is taken and extended to ...

Evaluation of an image-based tracking workflow with Kalman filtering for automatic image plane alignment in interventional MRI.

Science.gov (United States)

Neumann, M; Cuvillon, L; Breton, E; de Matheli, M

2013-01-01

Recently, a workflow for magnetic resonance (MR) image plane alignment based on tracking in real-time MR images was introduced. The workflow is based on a tracking device composed of 2 resonant micro-coils and a passive marker, and allows for tracking of the passive marker in clinical real-time images and automatic (re-)initialization using the microcoils. As the Kalman filter has proven its benefit as an estimator and predictor, it is well suited for use in tracking applications. In this paper, a Kalman filter is integrated in the previously developed workflow in order to predict position and orientation of the tracking device. Measurement noise covariances of the Kalman filter are dynamically changed in order to take into account that, according to the image plane orientation, only a subset of the 3D pose components is available. The improved tracking performance of the Kalman extended workflow could be quantified in simulation results. Also, a first experiment in the MRI scanner was performed but without quantitative results yet.

T839 fiber tracking transporter at New Muon Lab

International Nuclear Information System (INIS)

Krider, J.

1991-01-01

A darkbox and its transporter have been designed for T839 fiber tracking tests. The darkbox is 3.35 m x 0.76 m x 0.25 m (1·w·h) and contains a scintillating fiber ribbon suspension system and mechanical hardware to support the readout electronics. The transporter provides 3.0 m of horizontal motion transverse to the beam for linear scans of fiber characteristics. In addition, 70 degrees of rotation about a vertical axis is provided to simulate tracking of particles emanating from a collision point at lab angles in the range 0 degrees--70 degrees. The transporter, which is located inside a radiation area, is remotely controlled to permit scanning the fiber array through the region defined by four small stationary triggering scintillators without disabling beam. The transporter rails extend 20 feet to the west beyond a gate in the radiation enclosure fencing. This provides a staging area to work on the apparatus, while the beam is on. 4 figs

Extending the Search for Muon Neutrinos Coincident with Gamma-Ray Bursts in IceCube Data

Energy Technology Data Exchange (ETDEWEB)

Aartsen, M. G. [Department of Physics, University of Adelaide, Adelaide, 5005 (Australia); Ackermann, M. [DESY, D-15735 Zeuthen (Germany); Adams, J. [Dept. of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Aguilar, J. A.; Ansseau, I. [Université Libre de Bruxelles, Science Faculty CP230, B-1050 Brussels (Belgium); Ahlers, M. [Dept. of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI 53706 (United States); Ahrens, M. [Oskar Klein Centre and Dept. of Physics, Stockholm University, SE-10691 Stockholm (Sweden); Samarai, I. Al [Département de Physique Nucléaire et Corpusculaire, Université de Genève, CH-1211 Genève (Switzerland); Altmann, D.; Anton, G. [Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91058 Erlangen (Germany); Andeen, K. [Department of Physics, Marquette University, Milwaukee, WI 53201 (United States); Anderson, T. [Dept. of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Archinger, M.; Baum, V. [Institute of Physics, University of Mainz, Staudinger Weg 7, D-55099 Mainz (Germany); Argüelles, C.; Axani, S. [Dept. of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Auffenberg, J. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Bai, X. [Physics Department, South Dakota School of Mines and Technology, Rapid City, SD 57701 (United States); Barwick, S. W. [Dept. of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Collaboration: IceCube Collaboration; and others

2017-07-10

We present an all-sky search for muon neutrinos produced during the prompt γ -ray emission of 1172 gamma-ray bursts (GRBs) with the IceCube Neutrino Observatory. The detection of these neutrinos would constitute evidence for ultra-high-energy cosmic-ray (UHECR) production in GRBs, as interactions between accelerated protons and the prompt γ -ray field would yield charged pions, which decay to neutrinos. A previously reported search for muon neutrino tracks from northern hemisphere GRBs has been extended to include three additional years of IceCube data. A search for such tracks from southern hemisphere GRBs in five years of IceCube data has been introduced to enhance our sensitivity to the highest energy neutrinos. No significant correlation between neutrino events and observed GRBs is seen in the new data. Combining this result with previous muon neutrino track searches and a search for cascade signature events from all neutrino flavors, we obtain new constraints for single-zone fireball models of GRB neutrino and UHECR production.

Standard Test Method for Application and Analysis of Solid State Track Recorder (SSTR) Monitors for Reactor Surveillance, E706(IIIB)

CERN Document Server

American Society for Testing and Materials. Philadelphia

2003-01-01

1.1 This test method describes the use of solid-state track recorders (SSTRs) for neutron dosimetry in light-water reactor (LWR) applications. These applications extend from low neutron fluence to high neutron fluence, including high power pressure vessel surveillance and test reactor irradiations as well as low power benchmark field measurement. (1) This test method replaces Method E 418. This test method is more detailed and special attention is given to the use of state-of-the-art manual and automated track counting methods to attain high absolute accuracies. In-situ dosimetry in actual high fluence-high temperature LWR applications is emphasized. 1.2 This test method includes SSTR analysis by both manual and automated methods. To attain a desired accuracy, the track scanning method selected places limits on the allowable track density. Typically good results are obtained in the range of 5 to 800 000 tracks/cm2 and accurate results at higher track densities have been demonstrated for some cases. (2) Trac...

Extended RPA study of nuclear collective phenomena

International Nuclear Information System (INIS)

Drozdz, S.

1987-01-01

A fully microscopic study of nuclear collective phenomena is presented within the framework of an extended RPA which includes 1p-1h and 2p-2h excitations in a consistent way. This theory allows us to obtain a very realistic description of various excitation spectra. As a result, a strong evidence of correlation effects beyond mean-field theory emerges. The effective interaction used is a G-matrix derived from the meson-exchange potential. The extended theory introduces also additional correlations which screen the long-large part of the effective interaction. This effect significantly enhances the stability of the ground state against density fluctuations. In this connection a possible importance of relativistic effects is also discussed. 99 refs., 19 figs., 5 tabs. (author)

Target Tracking in 3-D Using Estimation Based Nonlinear Control Laws for UAVs

Directory of Open Access Journals (Sweden)

Mousumi Ahmed

2016-02-01

Full Text Available This paper presents an estimation based backstepping like control law design for an Unmanned Aerial Vehicle (UAV to track a moving target in 3-D space. A ground-based sensor or an onboard seeker antenna provides range, azimuth angle, and elevation angle measurements to a chaser UAV that implements an extended Kalman filter (EKF to estimate the full state of the target. A nonlinear controller then utilizes this estimated target state and the chaser’s state to provide speed, flight path, and course/heading angle commands to the chaser UAV. Tracking performance with respect to measurement uncertainty is evaluated for three cases: (1 stationary white noise; (2 stationary colored noise and (3 non-stationary (range correlated white noise. Furthermore, in an effort to improve tracking performance, the measurement model is made more realistic by taking into consideration range-dependent uncertainties in the measurements, i.e., as the chaser closes in on the target, measurement uncertainties are reduced in the EKF, thus providing the UAV with more accurate control commands. Simulation results for these cases are shown to illustrate target state estimation and trajectory tracking performance.

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

An engineering approach to extending lifespan in C. elegans.

Directory of Open Access Journals (Sweden)

Dror Sagi

Full Text Available We have taken an engineering approach to extending the lifespan of Caenorhabditis elegans. Aging stands out as a complex trait, because events that occur in old animals are not under strong natural selection. As a result, lifespan can be lengthened rationally using bioengineering to modulate gene expression or to add exogenous components. Here, we engineered longer lifespan by expressing genes from zebrafish encoding molecular functions not normally present in worms. Additionally, we extended lifespan by increasing the activity of four endogenous worm aging pathways. Next, we used a modular approach to extend lifespan by combining components. Finally, we used cell- and worm-based assays to analyze changes in cell physiology and as a rapid means to evaluate whether multi-component transgenic lines were likely to have extended longevity. Using engineering to add novel functions and to tune endogenous functions provides a new framework for lifespan extension that goes beyond the constraints of the worm genome.

The concurrent emergence and causes of double volcanic hotspot tracks on the Pacific plate

DEFF Research Database (Denmark)

Jones, David T; Davies, D. R.; Campbell, I. H.

2017-01-01

Mantle plumes are buoyant upwellings of hot rock that transport heat from Earth's core to its surface, generating anomalous regions of volcanism that are not directly associated with plate tectonic processes. The best-studied example is the Hawaiian-Emperor chain, but the emergence of two sub......-parallel volcanic tracks along this chain, Loa and Kea, and the systematic geochemical differences between them have remained unexplained. Here we argue that the emergence of these tracks coincides with the appearance of other double volcanic tracks on the Pacific plate and a recent azimuthal change in the motion...... of the plate. We propose a three-part model that explains the evolution of Hawaiian double-track volcanism: first, mantle flow beneath the rapidly moving Pacific plate strongly tilts the Hawaiian plume and leads to lateral separation between high- and low-pressure melt source regions; second, the recent...

A computer program TRACK_P for studying proton tracks in PADC detectors

Directory of Open Access Journals (Sweden)

D. Nikezic

2016-01-01

Full Text Available A computer program for studying proton tracks in solid state nuclear track detectors was developed and described in this paper. The program was written in Fortran 90, with an additional tool for visualizing the track appearance as seen under the optical microscope in the transmission mode, which was written in the Python programming language. Measurable track parameters were determined and displayed in the application window and written in a data file. Three-dimensional representation of tracks was enabled. Examples of calculated tracks were also given in the present paper.

Square tracking sensor for autonomous helicopter hover stabilization

Science.gov (United States)

Oertel, Carl-Henrik

1995-06-01

Sensors for synthetic vision are needed to extend the mission profiles of helicopters. A special task for various applications is the autonomous position hold of a helicopter above a ground fixed or moving target. As a proof of concept for a general synthetic vision solution a restricted machine vision system, which is capable of locating and tracking a special target, was developed by the Institute of Flight Mechanics of Deutsche Forschungsanstalt fur Luft- und Raumfahrt e.V. (i.e., German Aerospace Research Establishment). This sensor, which is specialized to detect and track a square, was integrated in the fly-by-wire helicopter ATTHeS (i.e., Advanced Technology Testing Helicopter System). An existing model following controller for the forward flight condition was adapted for the hover and low speed requirements of the flight vehicle. The special target, a black square with a length of one meter, was mounted on top of a car. Flight tests demonstrated the automatic stabilization of the helicopter above the moving car by synthetic vision.

An adaptive three-stage extended Kalman filter for nonlinear discrete-time system in presence of unknown inputs.

Science.gov (United States)

Xiao, Mengli; Zhang, Yongbo; Wang, Zhihua; Fu, Huimin

2018-04-01

Considering the performances of conventional Kalman filter may seriously degrade when it suffers stochastic faults and unknown input, which is very common in engineering problems, a new type of adaptive three-stage extended Kalman filter (AThSEKF) is proposed to solve state and fault estimation in nonlinear discrete-time system under these conditions. The three-stage UV transformation and adaptive forgetting factor are introduced for derivation, and by comparing with the adaptive augmented state extended Kalman filter, it is proven to be uniformly asymptotically stable. Furthermore, the adaptive three-stage extended Kalman filter is applied to a two-dimensional radar tracking scenario to illustrate the effect, and the performance is compared with that of conventional three stage extended Kalman filter (ThSEKF) and the adaptive two-stage extended Kalman filter (ATEKF). The results show that the adaptive three-stage extended Kalman filter is more effective than these two filters when facing the nonlinear discrete-time systems with information of unknown inputs not perfectly known. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Hail statistic in Western Europe based on a hyrid cell-tracking algorithm combining radar signals with hailstone observations

Science.gov (United States)

Fluck, Elody

2015-04-01

Hail statistic in Western Europe based on a hybrid cell-tracking algorithm combining radar signals with hailstone observations Elody Fluck¹, Michael Kunz¹ , Peter Geissbühler², Stefan P. Ritz² With hail damage estimated over Billions of Euros for a single event (e.g., hailstorm Andreas on 27/28 July 2013), hail constitute one of the major atmospheric risks in various parts of Europe. The project HAMLET (Hail Model for Europe) in cooperation with the insurance company Tokio Millennium Re aims at estimating hail probability, hail hazard and, combined with vulnerability, hail risk for several European countries (Germany, Switzerland, France, Netherlands, Austria, Belgium and Luxembourg). Hail signals are obtained from radar reflectivity since this proxy is available with a high temporal and spatial resolution using several hail proxies, especially radar data. The focus in the first step is on Germany and France for the periods 2005- 2013 and 1999 - 2013, respectively. In the next step, the methods will be transferred and extended to other regions. A cell-tracking algorithm TRACE2D was adjusted and applied to two dimensional radar reflectivity data from different radars operated by European weather services such as German weather service (DWD) and French weather service (Météo-France). Strong convective cells are detected by considering 3 connected pixels over 45 dBZ (Reflectivity Cores RCs) in a radar scan. Afterwards, the algorithm tries to find the same RCs in the next 5 minute radar scan and, thus, track the RCs centers over time and space. Additional information about hailstone diameters provided by ESWD (European Severe Weather Database) is used to determine hail intensity of the detected hail swaths. Maximum hailstone diameters are interpolated along and close to the individual hail tracks giving an estimation of mean diameters for the detected hail swaths. Furthermore, a stochastic event set is created by randomizing the parameters obtained from the

Real-time markerless tracking for augmented reality: the virtual visual servoing framework.

Science.gov (United States)

Comport, Andrew I; Marchand, Eric; Pressigout, Muriel; Chaumette, François

2006-01-01

Tracking is a very important research subject in a real-time augmented reality context. The main requirements for trackers are high accuracy and little latency at a reasonable cost. In order to address these issues, a real-time, robust, and efficient 3D model-based tracking algorithm is proposed for a "video see through" monocular vision system. The tracking of objects in the scene amounts to calculating the pose between the camera and the objects. Virtual objects can then be projected into the scene using the pose. Here, nonlinear pose estimation is formulated by means of a virtual visual servoing approach. In this context, the derivation of point-to-curves interaction matrices are given for different 3D geometrical primitives including straight lines, circles, cylinders, and spheres. A local moving edges tracker is used in order to provide real-time tracking of points normal to the object contours. Robustness is obtained by integrating an M-estimator into the visual control law via an iteratively reweighted least squares implementation. This approach is then extended to address the 3D model-free augmented reality problem. The method presented in this paper has been validated on several complex image sequences including outdoor environments. Results show the method to be robust to occlusion, changes in illumination, and mistracking.

Development of a tracking method for augmented reality applied to NPP maintenance work and its experimental evaluation

International Nuclear Information System (INIS)

Bian, Zhiqiang; Ishii, Hirotake; Shimoda, Hiroshi; Yoshikawa, Hidekazu; Morishita, Yoshitsugu; Kanehira, Yoshiki; Izumi, Masanori

2007-01-01

Nuclear power plants (NPPs) must be maintained periodically. Their maintenance efficiency must be improved and human error must be reduced simultaneously to improve NPPs' competitive capability in electricity markets. Although Augmented Reality (AR) offers great possibilities to support NPP maintenance work, some difficulties exist for application of AR to actual work support because current AR systems cannot be implemented in NPP environments without technical improvement. There are several kinds of problems such as recognition distance, tracking accuracy, and a complex working environment when applying AR to NPP field work support. Considerable extension of tracking distance and improvement of accuracy are particularly desired because NPPs are large scale indoor environments. This study designed a linecode marker, a new type of paper-based marker, along with recognition and tracking algorithms for it to resolve these problems. In contrast to conventional paper-based makers, such as square markers and circle markers, the linecode marker is not merely easier to set up in complex industrial environments: it also enables the use of AR in industrial plants because of its considerable tracking-performance improvement. To evaluate tracking accuracy, the trackable distance, and the tracking speed of the proposed tracking method, an evaluation experiment was conducted in a large room. The experiment results show that the tracking distance is extended extremely over that of the traditional marker-based tracking method: tracking accuracy improved to 20 cm over a 10 m distance. The running speed of the tracking can be as fast as 15 frames per second using a laptop PC. (author)

Long-term tracking of multiple interacting pedestrians using a single camera

CSIR Research Space (South Africa)

Keaikitse, M

2014-11-01

Full Text Available interacting pedestrians using a single camera Mogomotsi Keaikitse∗, Willie Brink† and Natasha Govender∗ ∗Modelling and Digital Sciences, Council for Scientific and Industrial Research, Pretoria, South Africa †Department of Mathematical Sciences, Stellenbosch...-identified and their tracks extended. Standard, publicly available data sets are used to test the system. I. INTRODUCTION Closed circuit cameras are becoming widespread and preva- lent in cities and towns around the world, indicating that surveillance is an important issue...

Interannual Variability of Northern Hemisphere Storm Tracks in Coarse-Gridded Datasets

Directory of Open Access Journals (Sweden)

Timothy Paul Eichler

2013-01-01

Full Text Available Extratropical cyclones exert a large socioeconomic impact. It is therefore important to assess their interannual variability. We generate cyclone tracks from the National Center for Environmental Prediction’s Reanalysis I and the European Centre for Medium Range Prediction ERA-40 reanalysis datasets. To investigate the interannual variability of cyclone tracks, we compare the effects of El Niño, the North Atlantic Oscillation (NAO, the Indian Ocean Dipole (IOD, and the Pacific North American Pattern (PNA on cyclone tracks. Composite analysis shows similar results for the impacts of El Niño, NAO, and the PNA on NH storm tracks. Although it is encouraging, we also found regional differences when comparing reanalysis datasets. The results for the IOD suggested a wave-like alteration of cyclone frequency across the northern US/Canada possibly related to Rossby wave propagation. Partial correlation demonstrates that although El Niño affects cyclone frequency in the North Pacific and along the US east coast, its impact on the North Pacific is accomplished via the PNA. Similarly, the PNA’s impact on US east coast storms is modulated via El Niño. In contrast, the impacts of the NAO extend as far west as the North Pacific and are not influenced by either the PNA or El Niño.

Self-tracking solar concentrator with an acceptance angle of 32°.

Science.gov (United States)

Zagolla, Volker; Dominé, Didier; Tremblay, Eric; Moser, Christophe

2014-12-15

Solar concentration has the potential to decrease the cost associated with solar cells by replacing the receiving surface aperture with cheaper optics that concentrate light onto a smaller cell aperture. However a mechanical tracker has to be added to the system to keep the concentrated light on the size reduced solar cell at all times. The tracking device itself uses energy to follow the sun's position during the day. We have previously shown a mechanism for self-tracking that works by making use of the infrared energy of the solar spectrum, to activate a phase change material. In this paper, we show an implementation of a working 53 x 53 mm(2) self-tracking system with an acceptance angle of 32° ( ± 16°). This paper describes the design optimizations and upscaling process to extend the proof-of-principle self-tracking mechanism to a working demonstration device including the incorporation of custom photodiodes for system characterization. The current version demonstrates an effective concentration of 3.5x (compared to 8x theoretical) over 80% of the desired acceptance angle. Further improvements are expected to increase the efficiency of the system and open the possibility to expand the device to concentrations as high as 200x (C(geo) = 400x, η = 50%, for a solar cell matched spectrum).

Target Tracking Using SePDAF under Ambiguous Angles for Distributed Array Radar

Science.gov (United States)

Long, Teng; Zhang, Honggang; Zeng, Tao; Chen, Xinliang; Liu, Quanhua; Zheng, Le

2016-01-01

Distributed array radar can improve radar detection capability and measurement accuracy. However, it will suffer cyclic ambiguity in its angle estimates according to the spatial Nyquist sampling theorem since the large sparse array is undersampling. Consequently, the state estimation accuracy and track validity probability degrades when the ambiguous angles are directly used for target tracking. This paper proposes a second probability data association filter (SePDAF)-based tracking method for distributed array radar. Firstly, the target motion model and radar measurement model is built. Secondly, the fusion result of each radar’s estimation is employed to the extended Kalman filter (EKF) to finish the first filtering. Thirdly, taking this result as prior knowledge, and associating with the array-processed ambiguous angles, the SePDAF is applied to accomplish the second filtering, and then achieving a high accuracy and stable trajectory with relatively low computational complexity. Moreover, the azimuth filtering accuracy will be promoted dramatically and the position filtering accuracy will also improve. Finally, simulations illustrate the effectiveness of the proposed method. PMID:27618058

Dynamic sensor tasking and IMM EKF estimation for tracking impulsively maneuvering satellites

Science.gov (United States)

Lace, Arthur A.

In order to efficiently maintain space situational awareness, care must be taken to optimally allocate expensive observation resources. In most situations the available sensors capable of tracking spacecraft have their time split between many different monitoring responsibilities. Tracking maneuvering spacecraft can be especially difficult as the schedule of maneuvers may not be known and will often throw off previous orbital models. Effectively solving this tasking problem is an ongoing focus of research in the area of space situational awareness. Most methods of automated tasking do not make use of interacting multiple model extended Kalman filter techniques to better track satellites during maneuvers. This paper proposes a modification to a Fisher information gain and estimated state covariance based sensor tasking method to take maneuver probability and multiple model dynamics into account. By incorporating the probabilistic maneuvering model, sensor tasking can be improved during satellite maneuvers using constrained resources. The proposed methods are verified through the use of numerical simulations with multiple maneuvering satellites and both orbital and ground-based sensors.

A parallel algorithm for 3D particle tracking and Lagrangian trajectory reconstruction

International Nuclear Information System (INIS)

Barker, Douglas; Zhang, Yuanhui; Lifflander, Jonathan; Arya, Anshu

2012-01-01

Particle-tracking methods are widely used in fluid mechanics and multi-target tracking research because of their unique ability to reconstruct long trajectories with high spatial and temporal resolution. Researchers have recently demonstrated 3D tracking of several objects in real time, but as the number of objects is increased, real-time tracking becomes impossible due to data transfer and processing bottlenecks. This problem may be solved by using parallel processing. In this paper, a parallel-processing framework has been developed based on frame decomposition and is programmed using the asynchronous object-oriented Charm++ paradigm. This framework can be a key step in achieving a scalable Lagrangian measurement system for particle-tracking velocimetry and may lead to real-time measurement capabilities. The parallel tracking algorithm was evaluated with three data sets including the particle image velocimetry standard 3D images data set #352, a uniform data set for optimal parallel performance and a computational-fluid-dynamics-generated non-uniform data set to test trajectory reconstruction accuracy, consistency with the sequential version and scalability to more than 500 processors. The algorithm showed strong scaling up to 512 processors and no inherent limits of scalability were seen. Ultimately, up to a 200-fold speedup is observed compared to the serial algorithm when 256 processors were used. The parallel algorithm is adaptable and could be easily modified to use any sequential tracking algorithm, which inputs frames of 3D particle location data and outputs particle trajectories

Kalman Filter Track Fits and Track Breakpoint Analysis

CERN Document Server

Astier, Pierre; Cousins, R D; Letessier-Selvon, A A; Popov, B A; Vinogradova, T G; Astier, Pierre; Cardini, Alessandro; Cousins, Robert D.; Letessier-Selvon, Antoine; Popov, Boris A.; Vinogradova, Tatiana

2000-01-01

We give an overview of track fitting using the Kalman filter method in the NOMAD detector at CERN, and emphasize how the wealth of by-product information can be used to analyze track breakpoints (discontinuities in track parameters caused by scattering, decay, etc.). After reviewing how this information has been previously exploited by others, we describe extensions which add power to breakpoint detection and characterization. We show how complete fits to the entire track, with breakpoint parameters added, can be easily obtained from the information from unbroken fits. Tests inspired by the Fisher F-test can then be used to judge breakpoints. Signed quantities (such as change in momentum at the breakpoint) can supplement unsigned quantities such as the various chisquares. We illustrate the method with electrons from real data, and with Monte Carlo simulations of pion decays.

On methodical problems in estimating geological temperature and time from measurements of fission tracks in apatite

International Nuclear Information System (INIS)

Jonckheere, R.

2003-01-01

The results of apatite fission-track modelling are only as accurate as the method, and depend on the assumption that the processes involved in the annealing of fossil tracks over geological times are the same as those responsible for the annealing of induced fission tracks in laboratory experiments. This has hitherto been assumed rather than demonstrated. The present critical discussion identifies a number of methodical problems from an examination of the available data on age standards, borehole samples and samples studied in the framework of geological investigations. These problems are related to low- ( 60 deg. C) annealing on a geological timescale and to the procedures used for calculating temperature-time paths from the fission-track data. It is concluded that it is not established that the relationship between track length and track density and the appearance of unetchable gaps, observed in laboratory annealing experiments on induced tracks, can be extrapolated to the annealing of fossil tracks on a geological timescale. This in turn casts doubt on the central principle of equivalent time. That such uncertainties still exist is in no small part due to an insufficient understanding of the formation, structure and properties of fission tracks at the atomic scale and to a lack of attention to the details of track revelation. The methodical implications of discrepancies between fission track results and the independent geological evidence are rarely considered. This presents a strong case for the re-involvement of track physicists in fundamental fission track research

Framework conditions for tracking electricity in Europe. E-TRACK WP2 report

International Nuclear Information System (INIS)

Lise, W.; Boots, M.G.; De Joode, J.; Ten Donkelaar, M.; Timpe, C.; Vrolijk, C.

2006-03-01

The analysis of this report shows that context matters for tracking generation attributes. On the one hand, there are factors that enable the introduction of tracking, like previous experiences with green certificates. Some Member States have already gained experience with tracking generation attributes, which is required to disclose the generation mix to the consumer. On the other hand, there are factors that are making the introduction of tracking generation attributes in Europe more difficult, like the widely varying initiatives among Member States with respect to legislation on GOs and disclosure. Also the market conditions can be of influence. The varying degree of market opening matters, because the usefulness of tracking is lower in a market where a customer cannot switch among suppliers. The amount of electricity traded makes it difficult to link generation to consumption under contract-based tracking, while this is of no concern under certificate-based tracking. One of the ways towards overcoming the aforementioned barriers is harmonisation of schemes for tracking generation attributes

Further Study on Strong Lagrangian Duality Property for Invex Programs via Penalty Functions

Directory of Open Access Journals (Sweden)

J. Zhang

2010-01-01

Full Text Available We apply the quadratic penalization technique to derive strong Lagrangian duality property for an inequality constrained invex program. Our results extend and improve the corresponding results in the literature.

Extended state observer based fuzzy model predictive control for ultra-supercritical boiler-turbine unit

International Nuclear Information System (INIS)

Zhang, Fan; Wu, Xiao; Shen, Jiong

2017-01-01

Highlights: • A novel ESOFMPC is proposed based on the combination of ESO and stable MPC. • The improved ESO can overcome unknown disturbances on any channel of MIMO system. • Nonlinearity and disturbance of boiler-turbine unit can be handled simultaneously. - Abstract: The regulation of ultra-supercritical (USC) boiler-turbine unit in large-scale power plants is vulnerable to various unknown disturbances, meanwhile, the internal nonlinearity makes it a challenging task for wide range load tracking. To overcome these two issues simultaneously, an extended state observer based fuzzy model predictive control is proposed for the USC boiler-turbine unit. Firstly, the fuzzy model of a 1000-MW coal-fired USC boiler-turbine unit is established through the nonlinearity analysis. Then a fuzzy stable model predictive controller is devised on the fuzzy model using output cost function for the purpose of wide range load tracking. An improved linear extended state observer, which can estimate plant behavior variations and unknown disturbances regardless of the direct feedthrough characteristic of the system, is synthesized with the predictive controller to enhance its disturbance rejection property. Closed-loop stability of the overall control system is guaranteed. Simulation results on a 1000-MW USC boiler-turbine unit model demonstrate the effectiveness of the proposed approach.

A Strong High Altitude Narrow Jet At Saturn'S Equator From Cassini/ISS Images

Science.gov (United States)

Garcia-Melendo, Enrique; Sánchez-Lavega, A.; Legarreta, J.; Pérez-Hoyos, S.; Hueso, R.

2010-10-01

The intense equatorial eastward jets observed at cloud level in Jupiter and Saturn, represent a major challenge for geophysical fluid dynamics. Saturn's equatorial jet is of particular interest in view of its three dimensional structure, suspected large temporal variability, and related stratospheric semiannual oscillation. Here we report the discovery at the upper cloud level of an extremely narrow and strong jet centered in the middle of the broad equatorial jet. Previously published works on Saturn's equatorial winds at cloud level provided only a partial coverage. Automatic correlation of brightness scans and manually tracked cloud features, retrieved from images obtained by the Cassini Imaging Science Subsystem (ISS), show that the jet reaches 430 ms-1 with a peak speed difference of 180 ms-1 relative to nearby latitudes at 60 mbar and 390 ms-1 at depths > 500 mbar. Images were obtained in two filters: MT3, centred at the 889nm strong methane absorption band, and CB3 centred at the near infrared 939nm continuum, which are sensitive to different altitude levels at the upper clouds and hazes. Contrarily to what is observed in other latitudes, its velocity increases with altitude. Our findings helps to extend the view we have of the equatorial stratospheric dynamics of fast rotating planets beyond the best known terrestrial environment, and extract more general consequences of the interaction between waves and mean flow. It remains to be known if this equatorial jet structure, now determined in detail in three dimensions, is permanent or variable with the seasonal solar insolation cycle, including the variable shadow cast by the rings. EGM, ASL, JL, SPH, and RH have been funded by the Spanish MICIIN AYA2009-10701 with FEDER support and ASL, JL, SPH, and RH by Grupos Gobierno Vasco IT-464-07

KOLAM: a cross-platform architecture for scalable visualization and tracking in wide-area imagery

Science.gov (United States)

Fraser, Joshua; Haridas, Anoop; Seetharaman, Guna; Rao, Raghuveer M.; Palaniappan, Kannappan

2013-05-01

KOLAM is an open, cross-platform, interoperable, scalable and extensible framework supporting a novel multi- scale spatiotemporal dual-cache data structure for big data visualization and visual analytics. This paper focuses on the use of KOLAM for target tracking in high-resolution, high throughput wide format video also known as wide-area motion imagery (WAMI). It was originally developed for the interactive visualization of extremely large geospatial imagery of high spatial and spectral resolution. KOLAM is platform, operating system and (graphics) hardware independent, and supports embedded datasets scalable from hundreds of gigabytes to feasibly petabytes in size on clusters, workstations, desktops and mobile computers. In addition to rapid roam, zoom and hyper- jump spatial operations, a large number of simultaneously viewable embedded pyramid layers (also referred to as multiscale or sparse imagery), interactive colormap and histogram enhancement, spherical projection and terrain maps are supported. The KOLAM software architecture was extended to support airborne wide-area motion imagery by organizing spatiotemporal tiles in very large format video frames using a temporal cache of tiled pyramid cached data structures. The current version supports WAMI animation, fast intelligent inspection, trajectory visualization and target tracking (digital tagging); the latter by interfacing with external automatic tracking software. One of the critical needs for working with WAMI is a supervised tracking and visualization tool that allows analysts to digitally tag multiple targets, quickly review and correct tracking results and apply geospatial visual analytic tools on the generated trajectories. One-click manual tracking combined with multiple automated tracking algorithms are available to assist the analyst and increase human effectiveness.

Tracks: Nurses and the Tracking Network

Centers for Disease Control (CDC) Podcasts

2012-06-06

This podcast highlights the utility of the National Environmental Public Health Tracking Network for nurses in a variety of work settings. It features commentary from the American Nurses Association and includes stories from a public health nurse in Massachusetts.  Created: 6/6/2012 by National Center for Environmental Health (NCEH)/Division of Environmental Hazards and Health Effects (DEHHE)/Environmental Health Tracking Branch (EHTB).   Date Released: 6/6/2012.

Decontaminate feature for tracking: adaptive tracking via evolutionary feature subset

Science.gov (United States)

Liu, Qiaoyuan; Wang, Yuru; Yin, Minghao; Ren, Jinchang; Li, Ruizhi

2017-11-01

Although various visual tracking algorithms have been proposed in the last 2-3 decades, it remains a challenging problem for effective tracking with fast motion, deformation, occlusion, etc. Under complex tracking conditions, most tracking models are not discriminative and adaptive enough. When the combined feature vectors are inputted to the visual models, this may lead to redundancy causing low efficiency and ambiguity causing poor performance. An effective tracking algorithm is proposed to decontaminate features for each video sequence adaptively, where the visual modeling is treated as an optimization problem from the perspective of evolution. Every feature vector is compared to a biological individual and then decontaminated via classical evolutionary algorithms. With the optimized subsets of features, the "curse of dimensionality" has been avoided while the accuracy of the visual model has been improved. The proposed algorithm has been tested on several publicly available datasets with various tracking challenges and benchmarked with a number of state-of-the-art approaches. The comprehensive experiments have demonstrated the efficacy of the proposed methodology.

Recovery of Pavlovian sign-tracking (autoshaping) following the discontinuation of inter-trial interval food in rats.

Science.gov (United States)

Kearns, David N; Weiss, Stanley J

2007-07-01

In pigeons, Pavlovian autoshaped keypecking produced by keylight-food pairings has been eliminated by introducing food during periods between CS presentations (i.e., during the inter-trial intervals). Keypecking eliminated in this manner reappears when the inter-trial USs are discontinued even though the CS is no longer paired with US. The present experiment investigated whether this recovery of responding produced by discontinuing unpaired inter-trial US presentations could be extended to another species, rats, within a Pavlovian sign-tracking paradigm. Rats were initially trained on a procedure where insertion of one retractable lever (CS(+)) was followed, response independently, with food, while insertion of another lever (CS(-)) was not paired with food. Rats quickly came to contact the CS(+) lever at high rates, but contacted the CS(-) lever infrequently. In the next phase, CS(+) was no longer followed by food. Explicitly unpaired food was presented only during the inter-trial intervals when both levers were absent. This treatment essentially eliminated the sign-tracking response. In the final phase, the unpaired inter-trial food presentations were discontinued while both CSs continued to be presented without food. This produced a significant recovery of the sign-tracking elicited by the CS(+) lever, extending the species generality of the Pavlovian resurgence phenomenon that has previously only been reported in pigeons, to rats.

Optimal Control Method of Robot End Position and Orientation Based on Dynamic Tracking Measurement

Science.gov (United States)

Liu, Dalong; Xu, Lijuan

2018-01-01

In order to improve the accuracy of robot pose positioning and control, this paper proposed a dynamic tracking measurement robot pose optimization control method based on the actual measurement of D-H parameters of the robot, the parameters is taken with feedback compensation of the robot, according to the geometrical parameters obtained by robot pose tracking measurement, improved multi sensor information fusion the extended Kalan filter method, with continuous self-optimal regression, using the geometric relationship between joint axes for kinematic parameters in the model, link model parameters obtained can timely feedback to the robot, the implementation of parameter correction and compensation, finally we can get the optimal attitude angle, realize the robot pose optimization control experiments were performed. 6R dynamic tracking control of robot joint robot with independent research and development is taken as experimental subject, the simulation results show that the control method improves robot positioning accuracy, and it has the advantages of versatility, simplicity, ease of operation and so on.

Tracking instrument and control for solar concentrators. Final technical report, October 1979-January 1981

Energy Technology Data Exchange (ETDEWEB)

Gray, J; Kuhlman, J

1981-01-31

The tracker uses a single photo sensor, and a rotating aperature to obtain tracking accuracies better than 1.5 mrads (0.1 degs). Peak signal detection is used to eliminate tracking of false sources, i.e., clouds, etc. A prism is employed to obtain an extended field of view (150 degs axially - 360 degs radially). The tracker digitally measures the Suns displacement angle relative to the concentrator axis, and repositions it incrementally. This arrangement permits the use of low cost non-servo motors. The local controller contains microprocessor based electronics, incorporating digital signal processing. A single controller may be time shared by a maximum of sixteen trackers, providing a high performance, cost effective solar tracking system, suitable for both line and point focus concentrators. An installation may have the local controller programmed as a standalone unit or slaved to a central controller. When used with a central controller, dynamic data monitoring and logging is available, together with the ability to change system modes and parameters, as desired.

Classical and quantum models of strong cosmic censorship

International Nuclear Information System (INIS)

Moncrief, V.E.

1983-01-01

The cosmic censorship conjecture states that naked singularities should not evolve from regular initial conditions in general relativity. In its strong form the conjecture asserts that space-times with Cauchy horizons must always be unstable and thus that the generic solution of Einstein's equations must be inextendible beyond its maximal Cauchy development. In this paper it is shown that one can construct an infinite-dimensional family of extendible cosmological solutions similar to Taub-NUT space-time; however, each of these solutions is unstable in precisely the way demanded by strong cosmic censorship. Finally it is shown that quantum fluctuations in the metric always provide (though in an unexpectedly subtle way) the ''generic perturbations'' which destroy the Cauchy horizons in these models. (author)

Classical and quantum models of strong cosmic censorship

Energy Technology Data Exchange (ETDEWEB)

Moncrief, V.E. (Yale Univ., New Haven, CT (USA). Dept. of Physics)

1983-04-01

The cosmic censorship conjecture states that naked singularities should not evolve from regular initial conditions in general relativity. In its strong form the conjecture asserts that space-times with Cauchy horizons must always be unstable and thus that the generic solution of Einstein's equations must be inextendible beyond its maximal Cauchy development. In this paper it is shown that one can construct an infinite-dimensional family of extendible cosmological solutions similar to Taub-NUT space-time; however, each of these solutions is unstable in precisely the way demanded by strong cosmic censorship. Finally it is shown that quantum fluctuations in the metric always provide (though in an unexpectedly subtle way) the ''generic perturbations'' which destroy the Cauchy horizons in these models.

Towards real-time detection and tracking of spatio-temporal features: Blob-filaments in fusion plasma

International Nuclear Information System (INIS)

Wu, Lingfei; Wu, Kesheng; Sim, Alex; Churchill, Michael; Choi, Jong Youl

2016-01-01

A novel algorithm and implementation of real-time identification and tracking of blob-filaments in fusion reactor data is presented. Similar spatio-temporal features are important in many other applications, for example, ignition kernels in combustion and tumor cells in a medical image. This work presents an approach for extracting these features by dividing the overall task into three steps: local identification of feature cells, grouping feature cells into extended feature, and tracking movement of feature through overlapping in space. Through our extensive work in parallelization, we demonstrate that this approach can effectively make use of a large number of compute nodes to detect and track blob-filaments in real time in fusion plasma. Here, on a set of 30GB fusion simulation data, we observed linear speedup on 1024 processes and completed blob detection in less than three milliseconds using Edison, a Cray XC30 system at NERSC.

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

Multiple player tracking in sports video: a dual-mode two-way bayesian inference approach with progressive observation modeling.

Science.gov (United States)

Xing, Junliang; Ai, Haizhou; Liu, Liwei; Lao, Shihong

2011-06-01

Multiple object tracking (MOT) is a very challenging task yet of fundamental importance for many practical applications. In this paper, we focus on the problem of tracking multiple players in sports video which is even more difficult due to the abrupt movements of players and their complex interactions. To handle the difficulties in this problem, we present a new MOT algorithm which contributes both in the observation modeling level and in the tracking strategy level. For the observation modeling, we develop a progressive observation modeling process that is able to provide strong tracking observations and greatly facilitate the tracking task. For the tracking strategy, we propose a dual-mode two-way Bayesian inference approach which dynamically switches between an offline general model and an online dedicated model to deal with single isolated object tracking and multiple occluded object tracking integrally by forward filtering and backward smoothing. Extensive experiments on different kinds of sports videos, including football, basketball, as well as hockey, demonstrate the effectiveness and efficiency of the proposed method.

An interface tracking model for droplet electrocoalescence.

Energy Technology Data Exchange (ETDEWEB)

Erickson, Lindsay Crowl

2013-09-01

This report describes an Early Career Laboratory Directed Research and Development (LDRD) project to develop an interface tracking model for droplet electrocoalescence. Many fluid-based technologies rely on electrical fields to control the motion of droplets, e.g. microfluidic devices for high-speed droplet sorting, solution separation for chemical detectors, and purification of biodiesel fuel. Precise control over droplets is crucial to these applications. However, electric fields can induce complex and unpredictable fluid dynamics. Recent experiments (Ristenpart et al. 2009) have demonstrated that oppositely charged droplets bounce rather than coalesce in the presence of strong electric fields. A transient aqueous bridge forms between approaching drops prior to pinch-off. This observation applies to many types of fluids, but neither theory nor experiments have been able to offer a satisfactory explanation. Analytic hydrodynamic approximations for interfaces become invalid near coalescence, and therefore detailed numerical simulations are necessary. This is a computationally challenging problem that involves tracking a moving interface and solving complex multi-physics and multi-scale dynamics, which are beyond the capabilities of most state-of-the-art simulations. An interface-tracking model for electro-coalescence can provide a new perspective to a variety of applications in which interfacial physics are coupled with electrodynamics, including electro-osmosis, fabrication of microelectronics, fuel atomization, oil dehydration, nuclear waste reprocessing and solution separation for chemical detectors. We present a conformal decomposition finite element (CDFEM) interface-tracking method for the electrohydrodynamics of two-phase flow to demonstrate electro-coalescence. CDFEM is a sharp interface method that decomposes elements along fluid-fluid boundaries and uses a level set function to represent the interface.

Formal Analysis of Functional Behaviour for Model Transformations Based on Triple Graph Grammars - Extended Version

OpenAIRE

Hermann, Frank; Ehrig, Hartmut; Orejas, Fernando; Ulrike, Golas

2010-01-01

Triple Graph Grammars (TGGs) are a well-established concept for the specification of model transformations. In previous work we have formalized and analyzed already crucial properties of model transformations like termination, correctness and completeness, but functional behaviour - especially local confluence - is missing up to now. In order to close this gap we generate forward translation rules, which extend standard forward rules by translation attributes keeping track of the elements whi...

Displacement monitoring of switch track and its slab on a bridge of high speed railway by FBG

Science.gov (United States)

Li, Weilai; Li, He; Cheng, Jian; Huang, Xiaomei; Pan, Jianjun; Zhou, Ciming; Yang, Minghong

2011-05-01

In a 350km/h high speed railway line, there is a seamless switch with ballastless slabs built on a bridge. 54 Fiber Bragg Grating detecting cells are employed to monitor the displacement of track and slab. The cell is of extending function of measurement range, up to 50mm displacement, and is of good linearity. Protecting methods for cells and fiber are adopted to keep them surviving from the harsh conditions. The results show that in 75 days, the displacement of the track and sleeper slab was 8-9mm, and the displacement is of high correlation with daily environmental temperature change.

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

Kalman filter-based tracking of moving objects using linear ultrasonic sensor array for road vehicles

Science.gov (United States)

Li, Shengbo Eben; Li, Guofa; Yu, Jiaying; Liu, Chang; Cheng, Bo; Wang, Jianqiang; Li, Keqiang

2018-01-01

Detection and tracking of objects in the side-near-field has attracted much attention for the development of advanced driver assistance systems. This paper presents a cost-effective approach to track moving objects around vehicles using linearly arrayed ultrasonic sensors. To understand the detection characteristics of a single sensor, an empirical detection model was developed considering the shapes and surface materials of various detected objects. Eight sensors were arrayed linearly to expand the detection range for further application in traffic environment recognition. Two types of tracking algorithms, including an Extended Kalman filter (EKF) and an Unscented Kalman filter (UKF), for the sensor array were designed for dynamic object tracking. The ultrasonic sensor array was designed to have two types of fire sequences: mutual firing or serial firing. The effectiveness of the designed algorithms were verified in two typical driving scenarios: passing intersections with traffic sign poles or street lights, and overtaking another vehicle. Experimental results showed that both EKF and UKF had more precise tracking position and smaller RMSE (root mean square error) than a traditional triangular positioning method. The effectiveness also encourages the application of cost-effective ultrasonic sensors in the near-field environment perception in autonomous driving systems.

Dirac particles in the field of magnetic monopoles and of strong electric charges

International Nuclear Information System (INIS)

Schafer, A.; Muller, B.; Greiner, W.

1985-01-01

The field of a magnetic pointlike monopole acts in a similar way on a charged Dirac particle as the field of a very strong electric point charge. To explore this parallel it is constructed a field solution for an extended magnetic-charge distribution. In contrast to what is found for extended electric charges, the Hamiltonian remains nonself-adjoint for an extended magnetic monopole. This suggests that there exist a fundamental difference between the two cases. In particular, the appearance of undefined states for point monopoles is not a consequence of the mere strength of the magnetic-monopole charge, which has a minimum value fixed by Dirac's quantization condition

Naturally etched tracks in apatites and the correction of fission track dating

CERN Document Server

Tien, J L

1999-01-01

Naturally etched tracks have been found in apatites from the rapid cooled, high-level Kunon pluton in the Zhangzhou Igneous Complex, SE China. This is manifested by the fact that the apatite fission track (FT) age derived from conventional counting of spontaneous and induced tracks yields a result of 140.6+-6.5 Ma, which is much older than the ages determined using other methods on different minerals from the same rock. When tracks are observed after etching the polished inner sections of the apatite grains, the naturally etched tracks characterized by having hazy boundaries can be distinguished from the normal tracks with sharp boundaries. The age obtained by omitting these fading-resistant hazy tracks, 76.5+-4.0 Ma, indicates the time of the Kunon pluton cooling down to approx 100 deg. C. The corrected peak age (73.8 Ma) is consistent with the other apatite FT peak ages (79.2 to 70.2 Ma) of the nearly contemporaneous plutons in the same igneous complex.

Statics and thermodynamics of strongly coupled multicomponent plasmas

International Nuclear Information System (INIS)

Rosenfeld, Y.

1980-01-01

A description of strongly coupled plasmas, in which the direct correlation functions, c/sub i/j(r), are obtained by simple scaling from a universal function, is derived and found to be in full agreement with available computer simulation data, which it thus extends for arbitrary mixtures. It is thermodynamically consistent with the ''ion-sphere'' charge-averaging prediction for the enhancement factors for nuclear reaction rates, the results for which confirm the universality of the bridge functions for mixtures

Ionizing gas breakdown waves in strong electric fields.

Science.gov (United States)

Klingbeil, R.; Tidman, D. A.; Fernsler, R. F.

1972-01-01

A previous analysis by Albright and Tidman (1972) of the structure of an ionizing potential wave driven through a dense gas by a strong electric field is extended to include atomic structure details of the background atoms and radiative effects, especially, photoionization. It is found that photoionization plays an important role in avalanche propagation. Velocities, electron densities, and temperatures are presented as a function of electric field for both negative and positive breakdown waves in nitrogen.

Sign tracking, but not goal tracking, is resistant to outcome devaluation

Directory of Open Access Journals (Sweden)

Sara E. Morrison

2015-12-01

Full Text Available During Pavlovian conditioning, a conditioned stimulus (CS may act as a predictor of a reward to be delivered in another location. Individuals vary widely in their propensity to engage with the CS (sign tracking or with the site of eventual reward (goal tracking. It is often assumed that sign tracking involves the association of the CS with the motivational value of the reward, resulting in the CS acquiring incentive value independent of the outcome. However, experimental evidence for this assumption is lacking. In order to test the hypothesis that sign tracking behavior does not rely on a neural representation of the outcome, we employed a reward devaluation procedure. We trained rats on a classic Pavlovian paradigm in which a lever CS was paired with a sucrose reward, then devalued the reward by pairing sucrose with illness in the absence of the CS. We found that sign tracking behavior was enhanced, rather than diminished, following reward devaluation; thus, sign tracking is clearly independent of a representation of the outcome. In contrast, goal tracking behavior was decreased by reward devaluation. Furthermore, when we divided rats into those with high propensity to engage with the lever (sign trackers and low propensity to engage with the lever (goal trackers, we found that nearly all of the effects of devaluation could be attributed to the goal trackers. These results show that sign tracking and goal tracking behavior may be the output of different associative structures in the brain, providing insight into the mechanisms by which reward-associated stimuli – such as drug cues – come to exert control over behavior in some individuals.

Sign Tracking, but Not Goal Tracking, is Resistant to Outcome Devaluation

Science.gov (United States)

Morrison, Sara E.; Bamkole, Michael A.; Nicola, Saleem M.

2015-01-01

During Pavlovian conditioning, a conditioned stimulus (CS) may act as a predictor of a reward to be delivered in another location. Individuals vary widely in their propensity to engage with the CS (sign tracking) or with the site of eventual reward (goal tracking). It is often assumed that sign tracking involves the association of the CS with the motivational value of the reward, resulting in the CS acquiring incentive value independent of the outcome. However, experimental evidence for this assumption is lacking. In order to test the hypothesis that sign tracking behavior does not rely on a neural representation of the outcome, we employed a reward devaluation procedure. We trained rats on a classic Pavlovian paradigm in which a lever CS was paired with a sucrose reward, then devalued the reward by pairing sucrose with illness in the absence of the CS. We found that sign tracking behavior was enhanced, rather than diminished, following reward devaluation; thus, sign tracking is clearly independent of a representation of the outcome. In contrast, goal tracking behavior was decreased by reward devaluation. Furthermore, when we divided rats into those with high propensity to engage with the lever (sign trackers) and low propensity to engage with the lever (goal trackers), we found that nearly all of the effects of devaluation could be attributed to the goal trackers. These results show that sign tracking and goal tracking behavior may be the output of different associative structures in the brain, providing insight into the mechanisms by which reward-associated stimuli—such as drug cues—come to exert control over behavior in some individuals. PMID:26733783

Sign-tracking (autoshaping) in rats: a comparison of cocaine and food as unconditioned stimuli.

Science.gov (United States)

Kearns, David N; Weiss, Stanley J

2004-11-01

A series of experiments was performed to determine whether sign-tracking would occur in rats with intravenous (i.v.) cocaine as the unconditioned stimulus. In Experiment 1, a retractable lever paired with food produced strong sign-tracking, but a lever paired with one of three doses of i.v. cocaine did not elicit any approach or contact behavior. Experiment 2 demonstrated that doses of cocaine that did not elicit sign-tracking would function as a positive reinforcer for a lever contact operant. In Experiment 3, an artificial consummatory response was added to make the cocaine reinforcement episode more behaviorally comparable to that occasioned by food. Although the rats readily performed this response when it was required to receive cocaine infusions, they still did not contact a lever that signaled the availability of these infusions. It appears that cocaine is different from other positive reinforcers (e.g., food, water, warmth, or intracranial stimulation) in that it will not produce sign-tracking in rats.

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.

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.

Range measurements and track kinetics in Dielectric Nuclear Track Detectors (DNTDs)

Energy Technology Data Exchange (ETDEWEB)

Aframian, A

1981-01-01

Observations of nuclear track development profiles and the kinetics of etched tracks in sensitive dielectric nuclear track detectors indicate three separate phases: the inception phase or the cone phase, the transition phase and the sphere phase. Continued etching of the sphere phase to through-tracks yields accurate range data for particles of different masses and energies and minimum critical angles of registration for each particle. The present results show an energy resolution of 40 keV (fwhm) for 5.48 MeV alpha-particles emitted from Am-241.

<strong>To See or not to Seestrong>

DEFF Research Database (Denmark)

Simonsen, Karen-Margrethe

2011-01-01

Artiklen handler om overvågningstemaet i moderne kunst med særlig fokus på Hasan Elahis netbaserede kunstværk "Tracking Transience". Elahi blev kort efter 9/11 anholdt mistænkt for terror. Siden den tid har han overvåget sit liv og 24 timer i døgnet kan man følge hans liv på nettet.Artiklen analy......Artiklen handler om overvågningstemaet i moderne kunst med særlig fokus på Hasan Elahis netbaserede kunstværk "Tracking Transience". Elahi blev kort efter 9/11 anholdt mistænkt for terror. Siden den tid har han overvåget sit liv og 24 timer i døgnet kan man følge hans liv på nettet...

Large scale tracking algorithms

Energy Technology Data Exchange (ETDEWEB)

Hansen, Ross L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Love, Joshua Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Melgaard, David Kennett [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Karelitz, David B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pitts, Todd Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zollweg, Joshua David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Anderson, Dylan Z. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nandy, Prabal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Whitlow, Gary L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bender, Daniel A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Byrne, Raymond Harry [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-01-01

Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

FEATURES OF THE RESEARCH WORK ELEMENTS DEFORMABILITY OF RAILWAY TRACK

Directory of Open Access Journals (Sweden)

I. O. Bondarenko

2015-06-01

Full Text Available Purpose. The scientific paper is supposed the determination of basic physical and structural conditions in modeling life cycle of the elements of the railway line for the study of deformation processes as the basis of normative base of the track at the condition of railway safety. Methodology. To achieve the aim principles of the elasticity theory and wave propagation process in the description of the interaction between the track and rolling stock were used. Findings. The basic physical and structural conditions under which it is necessary to carry out the simulation of the life cycle of the elements of the railway line for the study of deformation processes were determined. The basic physical and structural principles of drawing the design schemes of railway track elements for the process assessment of the track deformation work were formulated. The decision correctness and the possibility of the problem solution are proved. Originality. The study of the track reliability questions motivates the development of new models, allow considering it for some developments. There is a need to identify the main physical and structural conditions for assembly design schemes based on assessment and prediction of possible track state changes during its operation. The paper presents the basic principles of physical and structural drafting design schemes of railway line items for which Huygens’ principle is implemented. This principle can be performed only when the four dimensional space: the volume changing over time is considered. Practical value. Analytical models applied in determining the parameters of strength and resistance lines, fully satisfy the task, but can not be used to determine the parameters of track reliability. One of the main impossibility factors of these models is quasidynamic approach. Therefore, as a rule, receive and examine not only dynamic process of a railway track, but also its consequences. Besides, these models are related to

Radial Distribution Functions of Strongly Coupled Two-Temperature Plasmas

Science.gov (United States)

Shaffer, Nathaniel R.; Tiwari, Sanat Kumar; Baalrud, Scott D.

2017-10-01

We present tests of three theoretical models for the radial distribution functions (RDFs) in two-temperature strongly coupled plasmas. RDFs are useful in extending plasma thermodynamics and kinetic theory to strong coupling, but they are usually known only for thermal equilibrium or for approximate one-component model plasmas. Accurate two-component modeling is necessary to understand the impact of strong coupling on inter-species transport, e.g., ambipolar diffusion and electron-ion temperature relaxation. We demonstrate that the Seuferling-Vogel-Toeppfer (SVT) extension of the hypernetted chain equations not only gives accurate RDFs (as compared with classical molecular dynamics simulations), but also has a simple connection with the Yukawa OCP model. This connection gives a practical means to recover the structure of the electron background from knowledge of the ion-ion RDF alone. Using the model RDFs in Effective Potential Theory, we report the first predictions of inter-species transport coefficients of strongly coupled plasmas far from equilibrium. This work is supported by NSF Grant No. PHY-1453736, AFSOR Award No. FA9550-16-1-0221, and used XSEDE computational resources.

Quantization-Based Adaptive Actor-Critic Tracking Control With Tracking Error Constraints.

Science.gov (United States)

Fan, Quan-Yong; Yang, Guang-Hong; Ye, Dan

2018-04-01

In this paper, the problem of adaptive actor-critic (AC) tracking control is investigated for a class of continuous-time nonlinear systems with unknown nonlinearities and quantized inputs. Different from the existing results based on reinforcement learning, the tracking error constraints are considered and new critic functions are constructed to improve the performance further. To ensure that the tracking errors keep within the predefined time-varying boundaries, a tracking error transformation technique is used to constitute an augmented error system. Specific critic functions, rather than the long-term cost function, are introduced to supervise the tracking performance and tune the weights of the AC neural networks (NNs). A novel adaptive controller with a special structure is designed to reduce the effect of the NN reconstruction errors, input quantization, and disturbances. Based on the Lyapunov stability theory, the boundedness of the closed-loop signals and the desired tracking performance can be guaranteed. Finally, simulations on two connected inverted pendulums are given to illustrate the effectiveness of the proposed method.

Tropospheric mid-latitude geopotential wave characteristics associated with strong wind events in the North Atlantic/European region

Science.gov (United States)

Wild, Simon; Simmonds, Ian; Leckebusch, Gregor C.

2015-04-01

The variability of strong synoptic scale wind events in the mid-latitudes have long been linked to baroclinic wave activity in the mid troposphere. Previous studies have also shown that greater amplitudes of planetary waves in the mid troposphere are likely to increase the occurrence of regional extremes in temperature and precipitation. In this study we examine whether characteristics of planetary and synoptic mid-latitude waves show systematic anomalies in the North Atlantic/ European region which can be related to the occurrence of a strong surface wind event. We will mainly focus on two questions: 1) Do amplitudes for waves with different wave lengths show a systematic anomaly when a strong wind event occurs? 2) Can phases of the individual wave components be detected that favour strong wind events? In order to decompose the mid-tropospheric flow into longitudinal waves we employ the fast Fourier transform to the meridional mean of the geopotential height in 500hPa between 35° and 60°N for i) the entire latitude belt and ii) for a North Atlantic/European sector (36°W to 36°E). Our definition of strong wind events is based on the Storm Severity Index (SSI) alongside a wind tracking algorithm identifying areas of exceedances of the local 98th percentile of the 10m wind speed. First results using ERA-Interim Reanalysis from 1979 - 2014 for the extended winter season (ONDJFM) for the 50 most intense strong wind systems with respect to the SSI reveal a greater amplitude for all investigated wave numbers. Especially waves with wave lengths below 2000km show an increase of about 25% of the daily standard deviation on average. The distribution of wave phases for the different wave numbers with respect to the location of a strong wind event shows a less homogenous picture. There is however a high proportion of events that can be associated with phases around 3π/4 and 5π/4 of waves with lengths of around 6000km, equivalent to wave number 5 on a planetary scale

Making tracks

Energy Technology Data Exchange (ETDEWEB)

Anon.

1986-10-15

In many modern tracking chambers, the sense wires, rather than being lined up uniformly, are grouped into clusters to facilitate the pattern recognition process. However, with higher energy machines providing collisions richer in secondary particles, event reconstruction becomes more complicated. A Caltech / Illinois / SLAC / Washington group developed an ingenious track finding and fitting approach for the Mark III detector used at the SPEAR electron-positron ring at SLAC (Stanford). This capitalizes on the detector's triggering, which uses programmable logic circuits operating in parallel, each 'knowing' the cell patterns for all tracks passing through a specific portion of the tracker (drift chamber)

Method of plastic track detector electrochemical etching

International Nuclear Information System (INIS)

D'yakov, A.A.

1984-01-01

The review of studies dealing with the development of the method for the electro-chemical etching (ECE) of the plastic track detectors on the base of polyethy-leneterephthalate (PET) and polycarbonate (PC) is given. Physical essence of the method, basic parameters of the processes, applied equipment and methods of measurement automation are considered. The advantages of the method over the traditional chemical etching are pointed out. Recommendations on the detector operation modes when detecting fission fragments, α-particles and fast neutrons are given. The ECE method is based on the condition that during chemical etching the high-voltage sound frequency alternating electric field is applied to the detector. In this case the detector serves as an isolating layer betWeen two vessels with etching solution in which high-voltage electrode are submerged. At a fixed electric field potential higher (over than the threshold value) at the end of the etching track cone atree-like discharge spot arises. It is shown that when PET is used for fast neutron detection it is advisable to apply for ECE the PEW solution (15g KOH+40 g C 2 H 2 OH + 45g H 2 O) the field potential should constitute 30 kVxcm -1 at the freqUency of 9 kHz. In the case of fission fragment detection Using ECE and PC the following ECE conditions are recommended: 30% KOH etcher, field potential of 10 kVxcm -1 , 2-4 kHz frequency. It is concluded that the ECE method permits considerably eXtend the sphere of plastic track detector application for detecting ionizing particles,

Human immunodeficiency virus type 1 evolution in vivo tracked by DNA heteroduplex mobility assays

NARCIS (Netherlands)

Delwart, E. L.; Sheppard, H. W.; Walker, B. D.; Goudsmit, J.; Mullins, J. I.

1994-01-01

High mutation rates and strong selective pressures imposed on human immunodeficiency viruses in vivo result in the formation of pools of genetic variants known as quasispecies. DNA heteroduplex mobility and tracking analyses were used to monitor the generation of HIV sequence diversity, to estimate

Track finding and track reconstruction in the internal forward drift chamber of SAPHIR

International Nuclear Information System (INIS)

Umlauf, G.

1993-03-01

A track finding algorithm has been developed for the inner forward drift chamber of the SAPHIR detector (at ELSA in Bonn) using the Principal Components Analysis as a tool for interpolating track coordinates. The drift chamber consists of twelve planar layers with six different inclinations and is being operated in an inhomogenous magnetic field. The task of track finding is basicly split into a primary stage that defines track candidates without the use of drift-time information and a second stage that serves to verify the track candidate and to resolve the intrinsic left-right ambiguities of the drift chamber signals. Tracks with at most three missing signals can be found. (orig.) [de

IVF: exploiting intensity variation function for high-performance pedestrian tracking in forward-looking infrared imagery

Science.gov (United States)

Lamberti, Fabrizio; Sanna, Andrea; Paravati, Gianluca; Belluccini, Luca

2014-02-01

Tracking pedestrian targets in forward-looking infrared video sequences is a crucial component of a growing number of applications. At the same time, it is particularly challenging, since image resolution and signal-to-noise ratio are generally very low, while the nonrigidity of the human body produces highly variable target shapes. Moreover, motion can be quite chaotic with frequent target-to-target and target-to-scene occlusions. Hence, the trend is to design ever more sophisticated techniques, able to ensure rather accurate tracking results at the cost of a generally higher complexity. However, many of such techniques might not be suitable for real-time tracking in limited-resource environments. This work presents a technique that extends an extremely computationally efficient tracking method based on target intensity variation and template matching originally designed for targets with a marked and stable hot spot by adapting it to deal with much more complex thermal signatures and by removing the native dependency on configuration choices. Experimental tests demonstrated that, by working on multiple hot spots, the designed technique is able to achieve the robustness of other common approaches by limiting drifts and preserving the low-computational footprint of the reference method.

Timber tracking

DEFF Research Database (Denmark)

Düdder, Boris; Ross, Omry

2017-01-01

Managing and verifying forest products in a value chain is often reliant on easily manipulated document or digital tracking methods - Chain of Custody Systems. We aim to create a new means of tracking timber by developing a tamper proof digital system based on Blockchain technology. Blockchain...

Global Radiological Source Sorting, Tracking, and Monitoring Project: Phase I Final Report

International Nuclear Information System (INIS)

Walker, Randy M.; Hill, David E.; Gorman, Bryan L.

2010-01-01

As a proof of concept tested in an operational context, the Global Radiological Source Sorting, Tracking, and Monitoring (GRadSSTraM) Project successfully demonstrated that radio frequency identification (RFID) and Web 2.0* technologies can be deployed to track controlled shipments between the United States and the European Union. Between November 2009 and May 2010, a total of 19 shipments were successfully shipped from Oak Ridge National Laboratory (ORNL) by the U.S. Postal Service (USPS) and tracked to their delivery at England's National Physical Laboratory (NPL) by the United Kingdom Royal Mail. However, the project can only be viewed as a qualified success as notable shortcomings were observed. Although the origin and terminus of all RFID-enabled shipments were recorded and no shipments were lost, not all the waypoints between ORNL and NPL were incorporated into the pilot. Given limited resources, the project team was able to install RFID listeners/actuators at three waypoints between the two endpoints. Although it is likely that all shipments followed the same route between ORNL and NPL, it cannot be determined beyond question that all 19 shipments were routed on identical itineraries past the same three waypoints. The pilot also raises the distinct possibility that unattended RFID tracking alone, without positive confirmation that a tagged item has been properly recorded by an RFID reader, does not meet a rigorous standard for shipping controlled items. Indeed, the proof of concept test strongly suggests that a multifaceted approach to tracking may be called for, including tracking methods that are capable of reading and accepting multiple inputs for individual items (e.g., carrier-provided tracking numbers, Universal Product Codes (UPCs), and RFID tags). For controlled items, another apparent requirement is a confirmation feature, human or otherwise, which can certify that an item's RFID tag, UPC, or tracking number has been recorded.

Sky-Hook Control and Kalman Filtering in Nonlinear Model of Tracked Vehicle Suspension System

Directory of Open Access Journals (Sweden)

Jurkiewicz Andrzej

2017-09-01

Full Text Available The essence of the undertaken topic is application of the continuous sky-hook control strategy and the Extended Kalman Filter as the state observer in the 2S1 tracked vehicle suspension system. The half-car model of this suspension system consists of seven logarithmic spiral springs and two magnetorheological dampers which has been described by the Bingham model. The applied continuous sky-hook control strategy considers nonlinear stiffness characteristic of the logarithmic spiral springs. The control is determined on estimates generated by the Extended Kalman Filter. Improve of ride comfort is verified by comparing simulation results, under the same driving conditions, of controlled and passive vehicle suspension systems.

Dependence of yield of nuclear track-biosensors on track radius and analyte concentration

Science.gov (United States)

García-Arellano, H.; Muñoz H., G.; Fink, D.; Vacik, J.; Hnatowicz, V.; Alfonta, L.; Kiv, A.

2018-04-01

In swift heavy ion track-based polymeric biosensor foils with incorporated enzymes one exploits the correlation between the analyte concentration and the sensor current, via the enrichment of charged enzymatic reaction products in the track's confinement. Here we study the influence of the etched track radius on the biosensor's efficiency. These sensors are analyte-specific only if both the track radii and the analyte concentration exceed certain threshold values of ∼15 nm and ∼10-6 M (for glucose sensing), respectively. Below these limits the sensor signal stems un-specifically from any charge carrier. In its proper working regime, the inner track walls are smoothly covered by enzymes and the efficiency is practically radius independent. Theory shows that the measured current should be slightly sub-proportional to the analyte concentration; the measurements roughly reconfirm this. Narrower tracks (∼5-15 nm radius) with reduced enzyme coverage lead to decreasing efficiency. Tiny signals visible when the tracks are etched to effective radii between 0 and ∼5 nm are tentatively ascribed to enzymes bonded to surface-near nano-cracks in the polymer foil, resulting from its degradation due to aging, rather than to the tracks. Precondition for this study was the accurate determination of the etched track radii, which is possible only by a nanofluidic approach. This holds to some extent even for enzyme-covered tracks, though in this case most of the wall charges are compensated by enzyme bonding.

Tracks: A National Environmental Public Health Tracking Network Overview

Centers for Disease Control (CDC) Podcasts

In this podcast, Dr. Mike McGeehin, Director of CDC's Division of Environmental Hazards and Health Effects, provides an overview of the National Environmental Public Health Tracking Network. It highlights the Tracking Network's goal, how it will improve public health, its audience, and much more.

Urbanism on Track : Application of tracking technologies in urbanism

NARCIS (Netherlands)

Van der Hoeven, F.D.; Van Schaick, J.; Van der Spek, S.C.; Smit, M.G.J.

2008-01-01

Tracking technologies such as GPS, mobile phone tracking, video and RFID monitoring are rapidly becoming part of daily life. Technological progress offers huge possibilities for studying human activity patterns in time and space in new ways. Delft University of Technology (TU Delft) held an

Laser vision seam tracking system based on image processing and continuous convolution operator tracker

Science.gov (United States)

Zou, Yanbiao; Chen, Tao

2018-06-01

To address the problem of low welding precision caused by the poor real-time tracking performance of common welding robots, a novel seam tracking system with excellent real-time tracking performance and high accuracy is designed based on the morphological image processing method and continuous convolution operator tracker (CCOT) object tracking algorithm. The system consists of a six-axis welding robot, a line laser sensor, and an industrial computer. This work also studies the measurement principle involved in the designed system. Through the CCOT algorithm, the weld feature points are determined in real time from the noise image during the welding process, and the 3D coordinate values of these points are obtained according to the measurement principle to control the movement of the robot and the torch in real time. Experimental results show that the sensor has a frequency of 50 Hz. The welding torch runs smoothly with a strong arc light and splash interference. Tracking error can reach ±0.2 mm, and the minimal distance between the laser stripe and the welding molten pool can reach 15 mm, which can significantly fulfill actual welding requirements.

Anisotropy signature in reverse-time migration extended images

KAUST Repository

Sava, Paul C.; Alkhalifah, Tariq Ali

2014-01-01

Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

Anisotropy signature in reverse-time migration extended images

KAUST Repository

Sava, Paul C.

2014-11-04

Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

An insight on advantage of hybrid sun–wind-tracking over sun-tracking PV system

International Nuclear Information System (INIS)

Rahimi, Masoud; Banybayat, Meisam; Tagheie, Yaghoub; Valeh-e-Sheyda, Peyvand

2015-01-01

Graphical abstract: Real photograph of hybrid sun–wind-tracking system. - Highlights: • Novel hybrid sun–wind-tracking system proposed to enhance PV cell performance. • The wind tracker can cool down the PV cell as sun-tracking system work. • The hybrid tracker achieved 7.4% increase in energy gain over the sun tracker. • The overall daily output energy gain was increased by 49.83% by using this system. - Abstract: This paper introduces the design and application of a novel hybrid sun–wind-tracking system. This hybrid system employs cooling effect of wind, besides the advantages of tracking sun for enhancing power output from examined hybrid photovoltaic cell. The principal experiment focuses on comparison between dual-axes sun-tracking and hybrid sun–wind-tracking photovoltaic (PV) panels. The deductions based on the research tests confirm that the overall daily output energy gain was increased by 49.83% compared with that of a fixed system. Moreover, an overall increase of about 7.4% in the output power was found for the hybrid sun–wind-tracking over the two-axis sun tracking system.

Connection between strong and weak coupling in the mean spherical model in 1 + 1 dimensions

International Nuclear Information System (INIS)

Banks, J.L.

1980-01-01

I extend the strong-coupling expansion obtained by Srednicki, for the β-function of the mean spherical model in 1 + 1 dimensions, in the hamiltonian formulation. I use ordinary and two-point Pade approximants to extrapolate this result to weak coupling. I find a reasonably smooth connection between strong and weak coupling, and good numerical agreement with the exact solution. (orig.)

Track reconstruction for the P2 experiment

Energy Technology Data Exchange (ETDEWEB)

Tyukin, Alexey [JGU, Mainz (Germany); Collaboration: P2-Collaboration

2016-07-01

The P2 experiment at the future MESA accelerator in Mainz will measure elastically scattered electrons from a hydrogen or lead target in order to determine the parity violating asymmetry for different beam polarisations, which is created due to the weak charge of the target. The asymmetry can provide access to the Weinberg angle and the neutron skin of heavy nuclei. These quantities depend heavily on the momentum transfer Q{sup 2}, thus a reconstruction of single electron tracks in an inhomogeneous magnetic field is necessary. For this, the P2 detector will have four tracking planes of thin high voltage monolithic active pixel sensors (HV-MAPS). The scattered electrons propagate through a magnetic field and hit all four planes. In order to fit the hit positions the General Broken Lines method is used. As a fast propagator, a variation of the Runge-Kutta algorithm is applied, which solves the equation of motion in an inhomogeneous magnetic field numerically, such that the final state momentum and scattering angle can be reconstructed. The initial momentum and incident angle can vary strongly due to the thickness of the target, limiting the reconstruction quality. The average single track Q{sup 2} value of 0.006 GeV{sup 2}/c{sup 2} can be reconstructed with about 4 % uncertainty in a first analysis of the Geant4 simulation, leading to a high total precision due to large electron numbers in the experiment.

Non-etching nuclear track visualization in polymers: fluorescent and dyed tracks

International Nuclear Information System (INIS)

Somogyi, G.; Toth-Szilagyi, M.; Monnin, M.; Gourcy, J.

1979-01-01

A report is presented on progress in two methods of non-etching nuclear track visualization. The basis for one method is to graft polymer chains in the vicinity of the ion path in a polymer, and then to dye it, making the track visible. The second method is similar, but in this case saturated organic molecules can be used, which prevents subsequent polymerization. The detector is soaked with a solution of a sensitization molecule that can react with a convenient dye and fix it. The sensitization molecules may diffuse into the detector either through the bulk of it or/ and along the region damaged by a charged particle. Depending on the detailed procedure used, the tracks may be seen as 'dyed tracks' with visible-light illumination or as 'fluorescent tracks' with u.v. illumination. Experimental procedures and results are given and discussed. (U.K.)

Robust perception algorithms for road and track autonomous following

Science.gov (United States)

Marion, Vincent; Lecointe, Olivier; Lewandowski, Cecile; Morillon, Joel G.; Aufrere, Romuald; Marcotegui, Beatrix; Chapuis, Roland; Beucher, Serge

2004-09-01

The French Military Robotic Study Program (introduced in Aerosense 2003), sponsored by the French Defense Procurement Agency and managed by Thales Airborne Systems as the prime contractor, focuses on about 15 robotic themes, which can provide an immediate "operational add-on value." The paper details the "road and track following" theme (named AUT2), which main purpose was to develop a vision based sub-system to automatically detect roadsides of an extended range of roads and tracks suitable to military missions. To achieve the goal, efforts focused on three main areas: (1) Improvement of images quality at algorithms inputs, thanks to the selection of adapted video cameras, and the development of a THALES patented algorithm: it removes in real time most of the disturbing shadows in images taken in natural environments, enhances contrast and lowers reflection effect due to films of water. (2) Selection and improvement of two complementary algorithms (one is segment oriented, the other region based) (3) Development of a fusion process between both algorithms, which feeds in real time a road model with the best available data. Each previous step has been developed so that the global perception process is reliable and safe: as an example, the process continuously evaluates itself and outputs confidence criteria qualifying roadside detection. The paper presents the processes in details, and the results got from passed military acceptance tests, which trigger the next step: autonomous track following (named AUT3).

Nuclear fragmentation and the number of particle tracks in tissue

International Nuclear Information System (INIS)

Ponomarev, A. L.; Cucinotta, F. A.

2006-01-01

For high energy nuclei, the number of particle tracks per cell is modified by local nuclear reactions that occur, with large fluctuations expected for heavy ion tracks. Cells near the interaction site of a reaction will experience a much higher number of tracks than estimated by the average fluence. Two types of reaction products are possible and occur in coincidence; projectile fragments, which generally have smaller charge and similar velocity to that of the projectile, and target fragments, which are produced from the fragmentation of the nuclei of water atoms or other cellular constituents with low velocity. In order to understand the role of fragmentation in biological damage a new model of human tissue irradiated by heavy ions was developed. A box of the tissue is modelled with periodic boundary conditions imposed, which extrapolates the technique to macroscopic volumes of tissue. The cross sections for projectile and target fragmentation products are taken from the quantum multiple scattering fragmentation code previously developed at NASA Johnson Space Center. Statistics of fragmentation pathways occurring in a cell monolayer, as well as in a small volume of 10 x 10 x 10 cells are given. A discussion on approaches to extend the model to describe spatial distributions of inactivated or other cell damage types, as well as highly organised tissues of multiple cell types, is presented. (authors)

EnTracked: Energy-Efficient Robust Position Tracking for Mobile Devices

DEFF Research Database (Denmark)

Kjærgaard, Mikkel Baun; Jensen, Jakob Langdal; Godsk, Torben

2009-01-01

conditions and mobility, schedules position updates to both minimize energy consumption and optimize robustness. The realized system tracks pedestrian targets equipped with GPS-enabled devices. The system is configurable to realize different trade-offs between energy consumption and robustness. We provide...... of the mobile device. Furthermore, tracking has to robustly deliver position updates when faced with changing conditions such as delays due to positioning and communication, and changing positioning accuracy. This work proposes EnTracked --- a system that, based on the estimation and prediction of system...... extensive experimental results by profiling how devices consume power, by emulation on collected data and by validation in several real-world deployments. Results from this profiling show how a device consumes power while tracking its position. Results from the emulation indicate that the system can...

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)

A systematic review of patient tracking systems for use in the pediatric emergency department.

Science.gov (United States)

Dobson, Ian; Doan, Quynh; Hung, Geoffrey

2013-01-01

Patient safety is of great importance in the pediatric emergency department (PED). The combination of acutely and critically ill patients and high patient volumes creates a need for systems to support physicians in making accurate and timely diagnoses. Electronic patient tracking systems can potentially improve PED safety by reducing overcrowding and enhancing security. To enhance our understanding of current electronic tracking technologies, how they are implemented in a clinical setting, and resulting effect on patient care outcomes including patient safety. Nine databases were searched. Two independent reviewers identified articles that contained reference to patient tracking technologies in pediatrics or emergency medicine. Quantitative studies were assessed independently for methodological strength by two reviewers using an external assessment tool. Of 2292 initial articles, 22 were deemed relevant. Seventeen were qualitative, and the remaining five quantitative articles were assessed as being methodologically weak. Existing patient tracking systems in the ED included: infant monitoring/abduction prevention; barcode identification; radiofrequency identification (RFID)- or infrared (IR)-based patient tracking. Twenty articles supported the use of tracking technology to enhance patient safety or improve efficiency. One article failed to support the use of IR patient sensors due to study design flaws. Support exists for the use of barcode-, IR-, and RFID-based patient tracking systems to improve ED patient safety and efficiency. A lack of methodologically strong studies indicates a need for further evidence-based support for the implementation of patient tracking technology in a clinical or research setting. Copyright © 2013 Elsevier Inc. All rights reserved.

Robust visual tracking via structured multi-task sparse learning

KAUST Repository

Zhang, Tianzhu

2012-11-09

In this paper, we formulate object tracking in a particle filter framework as a structured multi-task sparse learning problem, which we denote as Structured Multi-Task Tracking (S-MTT). Since we model particles as linear combinations of dictionary templates that are updated dynamically, learning the representation of each particle is considered a single task in Multi-Task Tracking (MTT). By employing popular sparsity-inducing lp,q mixed norms (specifically p∈2,∞ and q=1), we regularize the representation problem to enforce joint sparsity and learn the particle representations together. As compared to previous methods that handle particles independently, our results demonstrate that mining the interdependencies between particles improves tracking performance and overall computational complexity. Interestingly, we show that the popular L1 tracker (Mei and Ling, IEEE Trans Pattern Anal Mach Intel 33(11):2259-2272, 2011) is a special case of our MTT formulation (denoted as the L11 tracker) when p=q=1. Under the MTT framework, some of the tasks (particle representations) are often more closely related and more likely to share common relevant covariates than other tasks. Therefore, we extend the MTT framework to take into account pairwise structural correlations between particles (e.g. spatial smoothness of representation) and denote the novel framework as S-MTT. The problem of learning the regularized sparse representation in MTT and S-MTT can be solved efficiently using an Accelerated Proximal Gradient (APG) method that yields a sequence of closed form updates. As such, S-MTT and MTT are computationally attractive. We test our proposed approach on challenging sequences involving heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that S-MTT is much better than MTT, and both methods consistently outperform state-of-the-art trackers. © 2012 Springer Science+Business Media New York.

Extending applicability of bimetric theory: chameleon bigravity

Science.gov (United States)

De Felice, Antonio; Mukohyama, Shinji; Uzan, Jean-Philippe

2018-02-01

This article extends bimetric formulations of massive gravity to make the mass of the graviton to depend on its environment. This minimal extension offers a novel way to reconcile massive gravity with local tests of general relativity without invoking the Vainshtein mechanism. On cosmological scales, it is argued that the model is stable and that it circumvents the Higuchi bound, hence relaxing the constraints on the parameter space. Moreover, with this extension the strong coupling scale is also environmentally dependent in such a way that it is kept sufficiently higher than the expansion rate all the way up to the very early universe, while the present graviton mass is low enough to be phenomenologically interesting. In this sense the extended bigravity theory serves as a partial UV completion of the standard bigravity theory. This extension is very generic and robust and a simple specific example is described.

Measurement of fission track of uranium particle by solid state nuclear track detector

International Nuclear Information System (INIS)

Son, S. C.; Pyo, H. W.; Ji, K. Y.; Kim, W. H.

2002-01-01

In this study, we discussed results of the measurement of fission tracks for the uranium containing particles by solid state nuclear track detector. Uranium containing silica and uranium oxide particles were prepared by uranium sorption onto silica powder in weak acidic medium and laser ablation on uranium pellet, respectively. Fission tracks for the uranium containing silica and uranium oxide particles were detected on Lexan plastic detector. It was found that the fission track size and shapes depend on the particle size uranium content in particles. Correlation of uranium particle diameter with fission track radius was also discussed

Strong-stability-preserving additive linear multistep methods

KAUST Repository

Hadjimichael, Yiannis

2018-02-20

The analysis of strong-stability-preserving (SSP) linear multistep methods is extended to semi-discretized problems for which different terms on the right-hand side satisfy different forward Euler (or circle) conditions. Optimal perturbed and additive monotonicity-preserving linear multistep methods are studied in the context of such problems. Optimal perturbed methods attain larger monotonicity-preserving step sizes when the different forward Euler conditions are taken into account. On the other hand, we show that optimal SSP additive methods achieve a monotonicity-preserving step-size restriction no better than that of the corresponding nonadditive SSP linear multistep methods.

Digital Watermark Tracking using Intelligent Multi-Agents System

Directory of Open Access Journals (Sweden)

Nagaraj V. DHARWADKAR

2010-01-01

Full Text Available E-commerce has become a huge business and adriving factor in the development of the Internet. Onlineshopping services are well established. Due to the evolution of2G and 3G mobile networks, soon online shopping services arecomplemented by their wireless counterparts. Furthermore, inthe recent years online delivery of digital media, such as MP3audio or video or image is very popular and will become anincreasingly important part of E-commerce. The advantage ofinternet is sharing the valuable digital data which lead to misuseof digital data. To resolve the problem of misuse of digital dataon Internet we need to have strong Digital rights monitoringsystem. Digital Rights Management (DRM is fairly youngdiscipline, while some of its underlying technologies have beenknown from many years. The use of DRM for managing andprotecting intellectual property rights is a comparatively newfield. In this paper we propose a model for online digital imagelibrary copyright protection based on watermark trackingSystem.In our proposed model the tracking of watermarks onremote host nodes is done using active mobile agents. The multiagentsystem architecture is used in watermark tracking whichsupports the coordination of several component tasks acrossdistributed and flexible networks of information sources.Whereas a centralized system is susceptible to system-widefailures and processing bottlenecks, multi-agent systems aremore reliable, especially given the likelihood of individualcomponent failures.

Strong Sporadic E Occurrence Detected by Ground-Based GNSS

Science.gov (United States)

Sun, Wenjie; Ning, Baiqi; Yue, Xinan; Li, Guozhu; Hu, Lianhuan; Chang, Shoumin; Lan, Jiaping; Zhu, Zhengping; Zhao, Biqiang; Lin, Jian

2018-04-01

The ionospheric sporadic E (Es) layer has significant impact on radio wave propagation. The traditional techniques employed for Es layer observation, for example, ionosondes, are not dense enough to resolve the morphology and dynamics of Es layer in spatial distribution. The ground-based Global Navigation Satellite Systems (GNSS) technique is expected to shed light on the understanding of regional strong Es occurrence, owing to the facts that the critical frequency (foEs) of strong Es structure is usually high enough to cause pulse-like disturbances in GNSS total electron content (TEC), and a large number of GNSS receivers have been deployed all over the world. Based on the Chinese ground-based GNSS networks, including the Crustal Movement Observation Network of China and the Beidou Ionospheric Observation Network, a large-scale strong Es event was observed in the middle latitude of China. The strong Es shown as a band-like structure in the southwest-northeast direction extended more than 1,000 km. By making a comparative analysis of Es occurrences identified from the simultaneous observations by ionosondes and GNSS TEC receivers over China middle latitude statistically, we found that GNSS TEC can be well employed to observe strong Es occurrence with a threshold value of foEs, 14 MHz.

A vortex filament tracking method for the Gross–Pitaevskii model of a superfluid

International Nuclear Information System (INIS)

Villois, Alberto; Proment, Davide; Salman, Hayder; Krstulovic, Giorgio

2016-01-01

We present an accurate and robust numerical method to track quantised vortex lines in a superfluid described by the Gross–Pitaevskii equation. By utilising the pseudo-vorticity field of the associated complex scalar order parameter of the superfluid, we are able to track the topological defects of the superfluid and reconstruct the vortex lines which correspond to zeros of the field. Throughout, we assume our field is periodic to allow us to make extensive use of the Fourier representation of the field and its derivatives in order to retain spectral accuracy. We present several case studies to test the precision of the method which include the evaluation of the curvature and torsion of a torus vortex knot, and the measurement of the Kelvin wave spectrum of a vortex line and a vortex ring. The method we present makes no a priori assumptions on the geometry of the vortices and is therefore applicable to a wide range of systems such as a superfluid in a turbulent state that is characterised by many vortex rings coexisting with sound waves. This allows us to track the positions of the vortex filaments in a dense turbulent vortex tangle and extract statistical information about the distribution of the size of the vortex rings and the inter-vortex separations. In principle, the method can be extended to track similar topological defects arising in other physical systems. (paper)

Particle tracking

International Nuclear Information System (INIS)

Mais, H.; Ripken, G.; Wrulich, A.; Schmidt, F.

1986-02-01

After a brief description of typical applications of particle tracking in storage rings and after a short discussion of some limitations and problems related with tracking we summarize some concepts and methods developed in the qualitative theory of dynamical systems. We show how these concepts can be applied to the proton ring HERA. (orig.)

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)

Attribute-Based Signcryption: Signer Privacy, Strong Unforgeability and IND-CCA Security in Adaptive-Predicates Model (Extended Version

Directory of Open Access Journals (Sweden)

Tapas Pandit

2016-08-01

Full Text Available Attribute-Based Signcryption (ABSC is a natural extension of Attribute-Based Encryption (ABE and Attribute-Based Signature (ABS, where one can have the message confidentiality and authenticity together. Since the signer privacy is captured in security of ABS, it is quite natural to expect that the signer privacy will also be preserved in ABSC. In this paper, first we propose an ABSC scheme which is weak existential unforgeable and IND-CCA secure in adaptive-predicates models and, achieves signer privacy. Then, by applying strongly unforgeable one-time signature (OTS, the above scheme is lifted to an ABSC scheme to attain strong existential unforgeability in adaptive-predicates model. Both the ABSC schemes are constructed on common setup, i.e the public parameters and key are same for both the encryption and signature modules. Our first construction is in the flavor of CtE&S paradigm, except one extra component that will be computed using both signature components and ciphertext components. The second proposed construction follows a new paradigm (extension of CtE&S , we call it “Commit then Encrypt and Sign then Sign” (CtE&S . The last signature is generated using a strong OTS scheme. Since, the non-repudiation is achieved by CtE&S paradigm, our systems also achieve the same.

Development of a railway wagon-track interaction model: Case studies on excited tracks

Science.gov (United States)

Xu, Lei; Chen, Xianmai; Li, Xuwei; He, Xianglin

2018-02-01

In this paper, a theoretical framework for modeling the railway wagon-ballast track interactions is presented, in which the dynamic equations of motion of wagon-track systems are constructed by effectively coupling the linear and nonlinear dynamic characteristics of system components. For the linear components, the energy-variational principle is directly used to derive their dynamic matrices, while for the nonlinear components, the dynamic equilibrium method is implemented to deduce the load vectors, based on which a novel railway wagon-ballast track interaction model is developed, and being validated by comparing with the experimental data measured from a heavy haul railway and another advanced model. With this study, extensive contributions in figuring out the critical speed of instability, limits and localizations of track irregularities over derailment accidents are presented by effectively integrating the dynamic simulation model, the track irregularity probabilistic model and time-frequency analysis method. The proposed approaches can provide crucial information to guarantee the running safety and stability of the wagon-track system when considering track geometries and various running speeds.

Ion track membranes providing heat pipe surfaces with capillary structures

International Nuclear Information System (INIS)

Akapiev, G.N.; Dmitriev, S.N.; Erler, B.; Shirkova, V.V.; Schulz, A.; Pietsch, H.

2003-01-01

The microgalvanic method for metal filling of etched ion tracks in organic foils is of particular interest for the fabrication of microsized structures. Microstructures like copper whiskers with a high aspect ratio produced in ion track membranes are suitable for the generation of high-performance heat transfer surfaces. A surface with good heat transfer characteristics is defined as a surface on which a small temperature difference causes a large heat transfer from the surface material to the liquid. It is well-known that a porous surface layer transfers to an evaporating liquid a given quantity of heat at a smaller temperature difference than does a usual smooth surface. Copper whiskers with high aspect ratio and a density 10 5 per cm 2 form such a porous structure, which produces strong capillary forces and therefore a maximum of heat transfer coefficients

Advanced Tracking of Vehicles

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Li, K.-J.; Pakalnis, Stardas

2005-01-01

efficient tracking techniques. More specifically, while almost all commercially available tracking solutions simply offer time-based sampling of positions, this paper's techniques aim to offer a guaranteed tracking accuracy for each vehicle at the lowest possible costs, in terms of network traffic...

Nuclear Fragmentation Induced by Relativistic Projectiles Studied in the 4$\\pi$ Configuration of Plastic Track Detectors

CERN Multimedia

2002-01-01

% EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...

‘What better excuse for a real adventure’: History, Memory and Tourism on the Kokoda Track

Directory of Open Access Journals (Sweden)

Jo Hawkins

2013-10-01

Full Text Available Rapidly growing numbers of Australian tourists visiting overseas battle sites associated with Australian military history have been met with enthusiastic academic interest by historians, yet the vast majority of studies focus on Gallipoli, rather than the Kokoda Track. Prior to 2001, few tourists had undertaken a journey along the narrow jungle pathway, which winds 96km through the Owen Stanley Ranges in Papua New Guinea. Just over a decade later, the track supports a competitive tourism industry, dominated by Australian companies, and attracts thousands of trekkers each year. This paper applies an interdisciplinary methodology to better understand the duality of locations of battlefield tourism as sites of commemoration and, unavoidably, sites of commerce. A survey of 107 trekkers suggests that, in addition to an expression of national identity, the mythology associated with the Kokoda Track has been appropriated by Australian tourists to represent individualistic goals of personal development and transformation: meanings that originate from the site’s history but extend beyond it.

Binomial distribution of Poisson statistics and tracks overlapping probability to estimate total tracks count with low uncertainty

International Nuclear Information System (INIS)

Khayat, Omid; Afarideh, Hossein; Mohammadnia, Meisam

2015-01-01

In the solid state nuclear track detectors of chemically etched type, nuclear tracks with center-to-center neighborhood of distance shorter than two times the radius of tracks will emerge as overlapping tracks. Track overlapping in this type of detectors causes tracks count losses and it becomes rather severe in high track densities. Therefore, tracks counting in this condition should include a correction factor for count losses of different tracks overlapping orders since a number of overlapping tracks may be counted as one track. Another aspect of the problem is the cases where imaging the whole area of the detector and counting all tracks are not possible. In these conditions a statistical generalization method is desired to be applicable in counting a segmented area of the detector and the results can be generalized to the whole surface of the detector. Also there is a challenge in counting the tracks in densely overlapped tracks because not sufficient geometrical or contextual information are available. It this paper we present a statistical counting method which gives the user a relation between the tracks overlapping probabilities on a segmented area of the detector surface and the total number of tracks. To apply the proposed method one can estimate the total number of tracks on a solid state detector of arbitrary shape and dimensions by approximating the tracks averaged area, whole detector surface area and some orders of tracks overlapping probabilities. It will be shown that this method is applicable in high and ultra high density tracks images and the count loss error can be enervated using a statistical generalization approach. - Highlights: • A correction factor for count losses of different tracks overlapping orders. • For the cases imaging the whole area of the detector is not possible. • Presenting a statistical generalization method for segmented areas. • Giving a relation between the tracks overlapping probabilities and the total tracks

A data fusion approach for track monitoring from multiple in-service trains

Science.gov (United States)

Lederman, George; Chen, Siheng; Garrett, James H.; Kovačević, Jelena; Noh, Hae Young; Bielak, Jacobo

2017-10-01

We present a data fusion approach for enabling data-driven rail-infrastructure monitoring from multiple in-service trains. A number of researchers have proposed using vibration data collected from in-service trains as a low-cost method to monitor track geometry. The majority of this work has focused on developing novel features to extract information about the tracks from data produced by individual sensors on individual trains. We extend this work by presenting a technique to combine extracted features from multiple passes over the tracks from multiple sensors aboard multiple vehicles. There are a number of challenges in combining multiple data sources, like different relative position coordinates depending on the location of the sensor within the train. Furthermore, as the number of sensors increases, the likelihood that some will malfunction also increases. We use a two-step approach that first minimizes position offset errors through data alignment, then fuses the data with a novel adaptive Kalman filter that weights data according to its estimated reliability. We show the efficacy of this approach both through simulations and on a data-set collected from two instrumented trains operating over a one-year period. Combining data from numerous in-service trains allows for more continuous and more reliable data-driven monitoring than analyzing data from any one train alone; as the number of instrumented trains increases, the proposed fusion approach could facilitate track monitoring of entire rail-networks.

Storm track response to climate change: Insights from simulations using an idealized dry GCM.

Science.gov (United States)

Mbengue, Cheikh; Schneider, Tapio

2013-04-01

The midlatitude storm tracks, where the most intense extratropical cyclones are found, are an important fixture in the general circulation. They are instrumental in balancing the Earth's heat, momentum, and moisture budgets and are responsible for the weather and climatic patterns over large regions of the Earth's surface. As a result, the midlatitude storm tracks are the subject of a considerable amount of scientific research to understand their response to global warming. This has produced the robust result showing that the storm tracks migrate poleward with global warming. However, the dynamical mechanisms responsible for this migration remain unclear. Our work seeks to broaden understanding of the dynamical mechanisms responsible for storm track migration. Competing mechanisms present in the comprehensive climate models often used to study storm track dynamics make it difficult to determine the primary mechanisms responsible for storm track migration. We are thus prompted to study storm track dynamics from a simplified and idealized framework, which enables the decoupling of mean temperature effects from the effects of static stability and of tropical from extratropical effects. Using a statistically zonally symmetric, dry general circulation model (GCM), we conduct a series of numerical simulations to help understand the storm track response to global mean temperatures and to the tropical convective static stability, which we can vary independently. We define storm tracks as regions of zonally and temporally averaged maxima of barotropic eddy kinetic energy (EKE). This storm track definition also allows us to use previously found scalings between the magnitude of bulk measures of mean available potential energy (MAPE) and EKE, to decompose MAPE, and to obtain some mechanistic understanding of the storm track response in our simulations. These simulations provide several insights, which enable us to extend upon existing theories on the mechanisms driving the

Real-Time Tumor Tracking in the Lung Using an Electromagnetic Tracking System

Energy Technology Data Exchange (ETDEWEB)

Shah, Amish P., E-mail: Amish.Shah@orlandohealth.com [Department of Radiation Oncology, MD Anderson Cancer Center Orlando, Orlando, Florida (United States); Kupelian, Patrick A.; Waghorn, Benjamin J.; Willoughby, Twyla R.; Rineer, Justin M.; Mañon, Rafael R.; Vollenweider, Mark A.; Meeks, Sanford L. [Department of Radiation Oncology, MD Anderson Cancer Center Orlando, Orlando, Florida (United States)

2013-07-01

Purpose: To describe the first use of the commercially available Calypso 4D Localization System in the lung. Methods and Materials: Under an institutional review board-approved protocol and an investigational device exemption from the US Food and Drug Administration, the Calypso system was used with nonclinical methods to acquire real-time 4-dimensional lung tumor tracks for 7 lung cancer patients. The aims of the study were to investigate (1) the potential for bronchoscopic implantation; (2) the stability of smooth-surface beacon transponders (transponders) after implantation; and (3) the ability to acquire tracking information within the lung. Electromagnetic tracking was not used for any clinical decision making and could only be performed before any radiation delivery in a research setting. All motion tracks for each patient were reviewed, and values of the average displacement, amplitude of motion, period, and associated correlation to a sinusoidal model (R{sup 2}) were tabulated for all 42 tracks. Results: For all 7 patients at least 1 transponder was successfully implanted. To assist in securing the transponder at the tumor site, it was necessary to implant a secondary fiducial for most transponders owing to the transponder's smooth surface. For 3 patients, insertion into the lung proved difficult, with only 1 transponder remaining fixed during implantation. One patient developed a pneumothorax after implantation of the secondary fiducial. Once implanted, 13 of 14 transponders remained stable within the lung and were successfully tracked with the tracking system. Conclusions: Our initial experience with electromagnetic guidance within the lung demonstrates that transponder implantation and tracking is achievable though not clinically available. This research investigation proved that lung tumor motion exhibits large variations from fraction to fraction within a single patient and that improvements to both transponder and tracking system are still

A development of radioactive material tracking and location control system

International Nuclear Information System (INIS)

Joo, Gwang Tae; Jung Seung Yong; Song, Jung Ho

2005-01-01

As the whole industry fields such as construction, chemistry, machine, medicine including nuclear-related field have extended the range of radioactive material uses, it is tendency that domestic uses of radioactive material have been increased in quantity and number. In addition, as the transportation, transfer and use of radioactive material have been frequent, its loss, robbery, and carelessness of handling may cause not only employees in charge but the public to worry about damage of explosion and put an obstacle to increase trust in nuclear-related industry. At present, though the transportation, use and storage of radioactive material conform to the institution and standard of the atomic energy law, if we tracking radioactive material in real time, we can take immediate actions to prevent its loss, robbery. As our research institute developed a terminal that control location and tracking real time location for gamma-ray projector used in transporting, transferring, and using nondestructive test, we take a good look at utilities by using GPS-Cell ID bases location control

An Energy-Efficient Sleep Strategy for Target Tracking Sensor Networks

Directory of Open Access Journals (Sweden)

Juan FENG

2014-02-01

Full Text Available Energy efficiency is very important for sensor networks since sensor nodes have limited energy supply from battery. So far, many researches have been focused on this issue, while less emphasis was placed on the optimal sleep time of each node. This paper proposed an adaptive energy conservation strategy for target tracking based on a grid network structure, where each node autonomously determines when and if to sleep. It allows sensor nodes far away from targets to sleep to save energy and guarantee the tracking accuracy. The proposed approach extend network lifetime by adopting an adaptive sleep scheduling scheme that combines the local power management (PM and the adaptive coordinate PM strategies to schedule the activities of sensor nodes. And each node can choose an optimal sleep time so as to make system adaptive and energy-efficient. We show the performance of our approach in terms of energy drop, comparing it to a naive approach, dynamic PM with fixed sleep time and the coordinate PM strategies. From the experimental results, it is readily seen that the efficiency of the proposed approach.

Controlled ion track etching

Science.gov (United States)

George, J.; Irkens, M.; Neumann, S.; Scherer, U. W.; Srivastava, A.; Sinha, D.; Fink, D.

2006-03-01

It is a common practice since long to follow the ion track-etching process in thin foils via conductometry, i.e . by measurement of the electrical current which passes through the etched track, once the track breakthrough condition has been achieved. The major disadvantage of this approach, namely the absence of any major detectable signal before breakthrough, can be avoided by examining the track-etching process capacitively. This method allows one to define precisely not only the breakthrough point before it is reached, but also the length of any non-transient track. Combining both capacitive and conductive etching allows one to control the etching process perfectly. Examples and possible applications are given.

Collaborative Tracking of Image Features Based on Projective Invariance

Science.gov (United States)

Jiang, Jinwei

In past manned lunar landing missions, such as Apollo 14, spatial disorientation of astronauts substantially compromised the productivities of astronauts, and caused safety and mission success problems. The non-GPS lunar environment has micro-gravity field, and lacks both spatial recognition cues and reference objects which are familiar to the human biological sensors related to spatial recognition (e.g. eyes). Such an environment causes misperceptions of the locations of astronauts and targets and their spatial relations, as well as misperceptions of the heading direction and travel distances of astronauts. These spatial disorientation effects can reduce productivity and cause life risks in lunar manned missions. A navigation system, which is capable of locating astronauts and tracking the movements of them on the lunar surface, is critical for future lunar manned missions where multiple astronauts will traverse more than 100km from the lander or the base station with the assistance from roving vehicle, and need real-time navigation support for effective collaborations among them. Our earlier research to solve these problems dealt with developing techniques to enable a precise, flexible and reliable Lunar Astronaut Spatial Orientation and Information System (LASOIS) capable of delivering real-time navigation information to astronauts on the lunar surface. The LASOIS hardware was a sensor network composed of orbital, ground and on-suit sensors: the Lunar Reconnaissance Orbiter Camera (LROC), radio beacons, the on-suit cameras, and shoe-mounted Inertial Measurement Unit (IMU). The LASOIS software included efficient and robust algorithms for estimating trajectory from IMU signals, generating heading information from imagery acquired from on-suit cameras, and an Extended Kalman Filter (EKF) based approach for integrating these spatial information components to generate the trajectory of an astronaut with meter-level accuracy. Moreover, LASOIS emphasized multi

Multitarget multisensor closed-loop tracking

Science.gov (United States)

Sanders-Reed, John N.

2004-07-01

This paper describes a closed-loop tracking system using multiple co-located sensors to develop multi-sensor track histories on multiple targets. The use of multiple, co-aligned sensors to track multiple, possibly maneuvering targets, presents a number of tracker design challenges and opportunities. Many of these problems have been addressed individually in the published literature from a theoretical point of view. However, no one has yet addressed the design and implementation of a specific tracker to meet all of these requirements at once. Specific questions addressed in this paper include how to assign N detections in a current frame to M active tracks, how to initiate new tracks and terminate dead tracks, how to combine information from multiple sensors into a single integrated picture, represented by a global track file, and how to perform these functions in a timely manner to support a precision closed loop tracking system.

Printed Tag Real-time Tracking

KAUST Repository

Bilal, Rana M.

2014-09-18

Disclosed are various embodiments for monitoring tracking devices capable of seamless indoor and outdoor tracking transitions. A tracking device may comprise, for example, printable circuitry and antennas combined with one or more receivers/transceivers on a substrate. The tracking device may be configured, for example, to localize the tracking device via GPS or an alternative localization strategy based on a determination of whether GPS communication is available. A modified RSSI fingerprinting methodology may be used to accurately determine a location of the tracking device using Wi-Fi access points. A device monitoring service may communicate with internal and/or external mapping API\\'s to render a device monitoring user interface comprising a visual representation of the location of the tracking device.

Thermal Tracking of Sports Players

Directory of Open Access Journals (Sweden)

Rikke Gade

2014-07-01

Full Text Available We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline multi-target tracking algorithm. Experiments are performed on a manually annotated 2-minutes video sequence of a real soccer game. The Kalman filter shows a very promising result on this rather challenging sequence with a tracking accuracy above 70% and is superior compared with the offline tracking approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels.

Thermal tracking of sports players.

Science.gov (United States)

Gade, Rikke; Moeslund, Thomas B

2014-07-29

We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline multi-target tracking algorithm. Experiments are performed on a manually annotated 2-minutes video sequence of a real soccer game. The Kalman filter shows a very promising result on this rather challenging sequence with a tracking accuracy above 70% and is superior compared with the offline tracking approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels.

Activity-Tracking Service for Building Operating Systems

DEFF Research Database (Denmark)

Hviid, Jakob; Kjærgaard, Mikkel Baun

2018-01-01

of Things sensors and devices promise to deliver rich data about human activities and control of loads. However, existing proposals for building operating systems that should combine such data and control opportunities does not provide concepts and support for activity data. In this paper we propose...... an activity-tracking service for building operating systems. The service is designed to consider the security, privacy, integration, extendability and scalability challenges in the building setting. We provide initial findings for testing the system in a proof of concept evaluation using a set of common......Several high consuming electricity loads in retail stores are currently highly intertwined in human activities. Without knowledge of such activities it is difficult to improve the energy efficiency of the loads operation for sustainability and cost reasons. The increasing availability of Internet...

Studies for a silicon telescope to extend the magnet facility at the DESY test beam

Energy Technology Data Exchange (ETDEWEB)

Tsionou, Dimitra [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, 22607 Hamburg (Germany)

2016-07-01

The International Large Detector is a detector concept for the International Linear Collider (ILC) which uses a Time Projection Chamber (TPC) as its main tracking detector. Within the framework of the LCTPC collaboration, a large prototype (LP) TPC has been built as a demonstrator. The LP has been equipped with Micro-Pattern Gas Detector modules and studied with an electron beam (1-6 GeV) in a 1 Tesla magnetic field at DESY. To extend the capabilities of the test beam setup, an external silicon tracker to be installed inside the magnet will be discussed. The silicon detector will provide high precision space points in front and behind the TPC inside the magnet. It will provide reference tracks that will allow to determine the momentum of the tracks passing the TPC, and which will help in correcting for field distortion effects in the LPTPC volume. In order to meet these requirements, simulation studies have been performed to determine the layout of the system and have placed stringent requirements on the sensor spatial resolution of better than 10 μ m. These studies will be presented along with the hardware options under evaluation.

Performance of the present ALICE Inner Tracking System and studies for the upgrade

International Nuclear Information System (INIS)

Contin, G

2012-01-01

The Inner Tracking System (ITS) of the ALICE experiment is made out of six layers of silicon detectors exploiting three different technologies (pixel, drift and strip). It covers the central pseudorapidity range of |η| < 0.9 and its distance from the beam line ranges from r = 3.9 cm for the innermost pixel layer up to r = 43 cm for the outermost strip layer. The main tasks of the ITS are to reconstruct the primary and secondary vertices, to track and identify charged particles with a low pt cutoff and to improve the momentum resolution at high pt. In this talk I will present the performance of the ITS in p-p and Pb-Pb collisions in 2010, both from the hardware point of view, with a brief overview of the features of the system, and the physics achievements for what concerns the vertexing, the tracking and the particle identification. Furthermore, I will give also an outlook on a possible upgrade of the ALICE ITS which is presently being studied, in order to extend its physics performance by improving the measurements of charmed hadrons and accessing new physics items like the measurement of the beauty hadrons.

Automatic detection of recoil-proton tracks and background rejection criteria in liquid scintillator-micro-capillary-array fast neutron spectrometer

Science.gov (United States)

Mor, Ilan; Vartsky, David; Dangendorf, Volker; Tittelmeier, Kai.; Weierganz, Mathias; Goldberg, Mark Benjamin; Bar, Doron; Brandis, Michal

2018-06-01

We describe an analysis procedure for automatic unambiguous detection of fast-neutron-induced recoil proton tracks in a micro-capillary array filled with organic liquid scintillator. The detector is viewed by an intensified CCD camera. This imaging neutron detector possesses the capability to perform high position-resolution (few tens of μm), energy-dispersive transmission-imaging using ns-pulsed beams. However, when operated with CW or DC beams, it also features medium-quality spectroscopic capabilities for incident neutrons in the energy range 2-20 MeV. In addition to the recoil proton events which display a continuous extended track structure, the raw images exhibit complex ion-tracks from nuclear interactions of fast-neutrons in the scintillator, capillaries quartz-matrix and CCD. Moreover, as expected, one also observes a multitude of isolated scintillation spots of varying intensity (henceforth denoted "blobs") that originate from several different sources, such as: fragmented proton tracks, gamma-rays, heavy-ion reactions as well as events and noise that occur in the image-intensifier and CCD. In order to identify the continuous-track recoil proton events and distinguish them from all these background events, a rapid, computerized and automatic track-recognition-procedure was developed. Based on an appropriately weighted analysis of track parameters such as: length, width, area and overall light intensity, the method is capable of distinguishing a single continuous-track recoil proton from typically surrounding several thousands of background events that are found in each CCD frame.

Periodic reference tracking control approach for smart material actuators with complex hysteretic characteristics

Science.gov (United States)

Sun, Zhiyong; Hao, Lina; Song, Bo; Yang, Ruiguo; Cao, Ruimin; Cheng, Yu

2016-10-01

Micro/nano positioning technologies have been attractive for decades for their various applications in both industrial and scientific fields. The actuators employed in these technologies are typically smart material actuators, which possess inherent hysteresis that may cause systems behave unexpectedly. Periodic reference tracking capability is fundamental for apparatuses such as scanning probe microscope, which employs smart material actuators to generate periodic scanning motion. However, traditional controller such as PID method cannot guarantee accurate fast periodic scanning motion. To tackle this problem and to conduct practical implementation in digital devices, this paper proposes a novel control method named discrete extended unparallel Prandtl-Ishlinskii model based internal model (d-EUPI-IM) control approach. To tackle modeling uncertainties, the robust d-EUPI-IM control approach is investigated, and the associated sufficient stabilizing conditions are derived. The advantages of the proposed controller are: it is designed and represented in discrete form, thus practical for digital devices implementation; the extended unparallel Prandtl-Ishlinskii model can precisely represent forward/inverse complex hysteretic characteristics, thus can reduce modeling uncertainties and benefits controllers design; in addition, the internal model principle based control module can be utilized as a natural oscillator for tackling periodic references tracking problem. The proposed controller was verified through comparative experiments on a piezoelectric actuator platform, and convincing results have been achieved.

Forward tracking detectors

Indian Academy of Sciences (India)

Abstract. Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

Testing strong factorial invariance using three-level structural equation modeling

Directory of Open Access Journals (Sweden)

Suzanne eJak

2014-07-01

Full Text Available Within structural equation modeling, the most prevalent model to investigate measurement bias is the multigroup model. Equal factor loadings and intercepts across groups in a multigroup model represent strong factorial invariance (absence of measurement bias across groups. Although this approach is possible in principle, it is hardly practical when the number of groups is large or when the group size is relatively small. Jak, Oort and Dolan (2013 showed how strong factorial invariance across large numbers of groups can be tested in a multilevel structural equation modeling framework, by treating group as a random instead of a fixed variable. In the present study, this model is extended for use with three-level data. The proposed method is illustrated with an investigation of strong factorial invariance across 156 school classes and 50 schools in a Dutch dyscalculia test, using three-level structural equation modeling.

Solution of the strong CP problem in models with scalars

International Nuclear Information System (INIS)

Dimopoulos, S.

1978-01-01

A possible solution to the strong CP problem is pointed out within the context of a Weinberg--Salam model with two Higgs fields coupled in a Peccei--Quinn symmetric fashion. This is done by extending the colour group to a bigger simple group which is broken at some very high energy. The model contains a heavy axion. No old or new U(1) problem re-emerges. 31 references

Lagrangian formulation for a gauge theory of strong and electromagnetic interactions defined on a Cartan bundle

International Nuclear Information System (INIS)

Drechsler, W.

1977-01-01

A Lagrangian formalism invariant under the gauge group U 1 xUSpsub(2.2) is set up in terms of spinor fields defined on a fiber bundle with Cartan connexion. The fiber of the Cartan bundle over space-time associated with strong interactions is characterized by an elementary length parameter R related to the range of the strong forces, and the structural group USpsub(2.2) of the bundle (being the covering group of the SOsub(4.1) de Sitter group) implies a gauge description of strong interactions based on the noncompact gauge group USpsub(2.2). The U 1 factor in the total gauge group corresponds to the usual gauge formulation for the electromagnetic interactions. The positivity of the energy associated with stable extended one-particle states in this dualistic description of charged hadronic matter immersed in the fiber geometry (this dualism is called strong fiber dynamics (SFD)) requires hadrons to be assigned to representations of the compact subgroup SU 2 xSU 2 of the strong-interaction gauge group USpsub(2.2). A brief discussion of the point-particle limit R→O is given by linking the presented SFD formalism for extended hadrons to an idealized description in terms of operators in a local quantum field theory

Track structure of protons and other light ions in liquid water: applications of the LIonTrack code at the nanometer scale.

Science.gov (United States)

Bäckström, G; Galassi, M E; Tilly, N; Ahnesjö, A; Fernández-Varea, J M

2013-06-01

The LIonTrack (Light Ion Track) Monte Carlo (MC) code for the simulation of H(+), He(2+), and other light ions in liquid water is presented together with the results of a novel investigation of energy-deposition site properties from single ion tracks. The continuum distorted-wave formalism with the eikonal initial state approximation (CDW-EIS) is employed to generate the initial energy and angle of the electrons emitted in ionizing collisions of the ions with H2O molecules. The model of Dingfelder et al. ["Electron inelastic-scattering cross sections in liquid water," Radiat. Phys. Chem. 53, 1-18 (1998); "Comparisons of calculations with PARTRAC and NOREC: Transport of electrons in liquid water," Radiat. Res. 169, 584-594 (2008)] is linked to the general-purpose MC code PENELOPE/penEasy to simulate the inelastic interactions of the secondary electrons in liquid water. In this way, the extended PENELOPE/penEasy code may provide an improved description of the 3D distribution of energy deposits (EDs), making it suitable for applications at the micrometer and nanometer scales. Single-ionization cross sections calculated with the ab initio CDW-EIS formalism are compared to available experimental values, some of them reported very recently, and the theoretical electronic stopping powers are benchmarked against those recommended by the ICRU. The authors also analyze distinct aspects of the spatial patterns of EDs, such as the frequency of nearest-neighbor distances for various radiation qualities, and the variation of the mean specific energy imparted in nanoscopic targets located around the track. For 1 MeV/u particles, the C(6+) ions generate about 15 times more clusters of six EDs within an ED distance of 3 nm than H(+). On average clusters of two to three EDs for 1 MeV/u H(+) and clusters of four to five EDs for 1 MeV/u C(6+) could be expected for a modeling double strand break distance of 3.4 nm.

The silicon tracking system of the CBM experiment at FAIR

Energy Technology Data Exchange (ETDEWEB)

Singla, Minni [GSI Darmstadt (Germany); Collaboration: CBM-Collaboration

2015-07-01

The Compressed Baryonic Matter (CBM) experiment, one of the major scientific pillars at FAIR, will explore the phase diagram of strongly interacting matter at the highest net-baryon densities in nucleus-nucleus collisions with interaction rates up to 10 MHz. The Silicon Tracking System is the central detector system of the CBM experiment. Its task is to perform track reconstruction and momentum determination for all charged particles created in beam-target collisions at SIS 100 and SIS 300 beam energies. The technical challenges to meet are a high granularity matching the high track densities, a fast self-triggering read-out coping with high interaction rates, and a low mass to yield high momentum resolution of Δp/p=1%. The detector system acceptance covers polar angles between 2.5 and 25 degrees and will be operated in the 1 T field of a superconducting dipole magnet. We introduce the concept of the STS, being comprised of eight tracking stations employing ∝1300 double-sided silicon microstrip sensors on modular structures that keep the read-out electronics outside the physics aperture. Ultra-thin-multiline micro-cables will be used to bridge the distance between the microstrip sensors and the readout electronics. Infrastructure such as power lines and cooling plates will be placed at the periphery of the stations. The status of the STS development is summarized in the presentation, including an overview on sensors, read-out electronics, prototypes, and system integration.

Robust Position Tracking for Electro-Hydraulic Drives Based on Generalized Feedforward Compensation Approach

DEFF Research Database (Denmark)

Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

2012-01-01

This paper presents a robust tracking control concept based on accurate feedforward compensation for hydraulic valve-cylinder drives. The proposed feedforward compensator is obtained utilizing a generalized description of the valve flow that takes into account any asymmetry of valves and...... constant gain type feedforward compensator, when subjected to strong perturbations in supply pressure and coulomb friction....

Variability of the North Atlantic summer storm track: mechanisms and impacts on European climate

International Nuclear Information System (INIS)

Dong, Buwen; Sutton, Rowan T; Woollings, Tim; Hodges, Kevin

2013-01-01

The summertime variability of the extratropical storm track over the Atlantic sector and its links to European climate have been analysed for the period 1948–2011 using observations and reanalyses. The main results are as follows. (1) The dominant mode of the summer storm track density variability is characterized by a meridional shift of the storm track between two distinct paths and is related to a bimodal distribution in the climatology for this region. It is also closely related to the Summer North Atlantic Oscillation (SNAO). (2) A southward shift is associated with a downstream extension of the storm track and a decrease in blocking frequency over the UK and northwestern Europe. (3) The southward shift is associated with enhanced precipitation over the UK and northwestern Europe and decreased precipitation over southern Europe (contrary to the behaviour in winter). (4) There are strong ocean–atmosphere interactions related to the dominant mode of storm track variability. The atmosphere forces the ocean through anomalous surface fluxes and Ekman currents, but there is also some evidence consistent with an ocean influence on the atmosphere, and that coupled ocean–atmosphere feedbacks might play a role. The ocean influence on the atmosphere may be particularly important on decadal timescales, related to the Atlantic Multidecadal Oscillation (AMO). (letter)

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

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

Dynamical Symmetry Breaking of Extended Gauge Symmetries

OpenAIRE

Appelquist, Thomas; Shrock, Robert

2003-01-01

We construct asymptotically free gauge theories exhibiting dynamical breaking of the left-right, strong-electroweak gauge group $G_{LR} = {\\rm SU}(3)_c \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R \\times {\\rm U}(1)_{B-L}$, and its extension to the Pati-Salam gauge group $G_{422}={\\rm SU}(4)_{PS} \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R$. The models incorporate technicolor for electroweak breaking, and extended technicolor for the breaking of $G_{LR}$ and $G_{422}$ and the generation of fermion ...

Evaluating the Impact of Internships - Longitudinal Participant Tracking in the Soars Program

Science.gov (United States)

Haacker, R.; Sloan, V.

2014-12-01

While there is widespread agreement about the benefits of research internship experiences for students, long-term tracking of student progress beyond the summer experience is challenging. Coordinated tracking can effectively document program impact, inform programmatic improvement, and identifying gaps in the internship effort. Tracking can also strengthen diversity efforts and the retention of students from underrepresented groups. Continuous follow-up and guidance can only be provided to students if we know where they are, what they are doing and what they need in order to stay engaged in the field. The SOARS Program at the National Center for Atmospheric Research has supported undergraduate students for over 18 years to enter and succeed in graduate school. Over 85% of SOARS participants have transitioned to geoscience graduate programs or the STEM workforce. The SOARS mission is to broaden participation in the atmospheric and related sciences by engaging students from groups historically under-represented in science, including Black or African-American, American Indian or Alaska Native, Hispanic or Latino, female, first-generation college students, and students with disabilities. SOARS relies on proven intervention strategies such as multi-year research experiences, multifaceted mentoring, and a strong learning community. Fostering relationships developed during this time using a wider range of technologies and program longevity play important roles in tracking participants over time. This presentation will highlight significant program results and share the tracking and evaluation techniques utilized in SOARS.

Fast track-hoftealloplastik

DEFF Research Database (Denmark)

Hansen, Torben Bæk; Gromov, Kirill; Kristensen, Billy B

2017-01-01

Fast-track surgery implies a coordinated perioperative approach aimed at reducing surgical stress and facilitating post-operative recovery. The fast-track programme has reduced post-operative length of stay and has led to shorter convalescence with more rapid functional recovery and decreased...... morbidity and mortality in total hip arthroplasty. It should now be a standard total hip arthroplasty patient pathway, but fine tuning of the multiple factors in the fast-track pathway is still needed in patients with special needs or high comorbidity burden....

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

EVA: laparoscopic instrument tracking based on Endoscopic Video Analysis for psychomotor skills assessment.

Science.gov (United States)

Oropesa, Ignacio; Sánchez-González, Patricia; Chmarra, Magdalena K; Lamata, Pablo; Fernández, Alvaro; Sánchez-Margallo, Juan A; Jansen, Frank Willem; Dankelman, Jenny; Sánchez-Margallo, Francisco M; Gómez, Enrique J

2013-03-01

The EVA (Endoscopic Video Analysis) tracking system is a new system for extracting motions of laparoscopic instruments based on nonobtrusive video tracking. The feasibility of using EVA in laparoscopic settings has been tested in a box trainer setup. EVA makes use of an algorithm that employs information of the laparoscopic instrument's shaft edges in the image, the instrument's insertion point, and the camera's optical center to track the three-dimensional position of the instrument tip. A validation study of EVA comprised a comparison of the measurements achieved with EVA and the TrEndo tracking system. To this end, 42 participants (16 novices, 22 residents, and 4 experts) were asked to perform a peg transfer task in a box trainer. Ten motion-based metrics were used to assess their performance. Construct validation of the EVA has been obtained for seven motion-based metrics. Concurrent validation revealed that there is a strong correlation between the results obtained by EVA and the TrEndo for metrics, such as path length (ρ = 0.97), average speed (ρ = 0.94), or economy of volume (ρ = 0.85), proving the viability of EVA. EVA has been successfully validated in a box trainer setup, showing the potential of endoscopic video analysis to assess laparoscopic psychomotor skills. The results encourage further implementation of video tracking in training setups and image-guided surgery.

Diamond detector time resolution for large angle tracks

Energy Technology Data Exchange (ETDEWEB)

Chiodini, G., E-mail: chiodini@le.infn.it [INFN - Sezione di Lecce (Italy); Fiore, G.; Perrino, R. [INFN - Sezione di Lecce (Italy); Pinto, C.; Spagnolo, S. [INFN - Sezione di Lecce (Italy); Dip. di Matematica e Fisica “Ennio De Giorgi”, Uni. del Salento (Italy)

2015-10-01

The applications which have stimulated greater interest in diamond sensors are related to detectors close to particle beams, therefore in an environment with high radiation level (beam monitor, luminosity measurement, detection of primary and secondary-interaction vertices). Our aims is to extend the studies performed so far by developing the technical advances needed to prove the competitiveness of this technology in terms of time resolution, with respect to more usual ones, which does not guarantee the required tolerance to a high level of radiation doses. In virtue of these goals, measurements of diamond detector time resolution with tracks incident at different angles are discussed. In particular, preliminary testbeam results obtained with 5 GeV electrons and polycrystalline diamond strip detectors are shown.

Assessment of the pseudo-tracking approach for the calculation of material acceleration and pressure fields from time-resolved PIV: part I. Error propagation

Science.gov (United States)

van Gent, P. L.; Schrijer, F. F. J.; van Oudheusden, B. W.

2018-04-01

Pseudo-tracking refers to the construction of imaginary particle paths from PIV velocity fields and the subsequent estimation of the particle (material) acceleration. In view of the variety of existing and possible alternative ways to perform the pseudo-tracking method, it is not straightforward to select a suitable combination of numerical procedures for its implementation. To address this situation, this paper extends the theoretical framework for the approach. The developed theory is verified by applying various implementations of pseudo-tracking to a simulated PIV experiment. The findings of the investigations allow us to formulate the following insights and practical recommendations: (1) the velocity errors along the imaginary particle track are primarily a function of velocity measurement errors and spatial velocity gradients; (2) the particle path may best be calculated with second-order accurate numerical procedures while ensuring that the CFL condition is met; (3) least-square fitting of a first-order polynomial is a suitable method to estimate the material acceleration from the track; and (4) a suitable track length may be selected on the basis of the variation in material acceleration with track length.

Passive Target Tracking in Non-cooperative Radar System Based on Particle Filtering

Institute of Scientific and Technical Information of China (English)

LI Shuo; TAO Ran

2006-01-01

We propose a target tracking method based on particle filtering(PF) to solve the nonlinear non-Gaussian target-tracking problem in the bistatic radar systems using external radiation sources. Traditional nonlinear state estimation method is extended Kalman filtering (EKF), which is to do the first level Taylor series extension. It will cause an inaccuracy or even a scatter estimation result on condition that there is either a highly nonlinear target or a large noise square-error. Besides, Kalman filtering is the optimal resolution under a Gaussian noise assumption, and is not suitable to the non-Gaussian condition. PF is a sort of statistic filtering based on Monte Carlo simulation that is using some random samples (particles) to simulate the posterior probability density of system random variables. This method can be used in any nonlinear random system. It can be concluded through simulation that PF can achieve higher accuracy than the traditional EKF.

Convergent Time-Varying Regression Models for Data Streams: Tracking Concept Drift by the Recursive Parzen-Based Generalized Regression Neural Networks.

Science.gov (United States)

Duda, Piotr; Jaworski, Maciej; Rutkowski, Leszek

2018-03-01

One of the greatest challenges in data mining is related to processing and analysis of massive data streams. Contrary to traditional static data mining problems, data streams require that each element is processed only once, the amount of allocated memory is constant and the models incorporate changes of investigated streams. A vast majority of available methods have been developed for data stream classification and only a few of them attempted to solve regression problems, using various heuristic approaches. In this paper, we develop mathematically justified regression models working in a time-varying environment. More specifically, we study incremental versions of generalized regression neural networks, called IGRNNs, and we prove their tracking properties - weak (in probability) and strong (with probability one) convergence assuming various concept drift scenarios. First, we present the IGRNNs, based on the Parzen kernels, for modeling stationary systems under nonstationary noise. Next, we extend our approach to modeling time-varying systems under nonstationary noise. We present several types of concept drifts to be handled by our approach in such a way that weak and strong convergence holds under certain conditions. Finally, in the series of simulations, we compare our method with commonly used heuristic approaches, based on forgetting mechanism or sliding windows, to deal with concept drift. Finally, we apply our concept in a real life scenario solving the problem of currency exchange rates prediction.

Fast and Accurate Rat Head Motion Tracking With Point Sources for Awake Brain PET.

Science.gov (United States)

Miranda, Alan; Staelens, Steven; Stroobants, Sigrid; Verhaeghe, Jeroen

2017-07-01

To avoid the confounding effects of anesthesia and immobilization stress in rat brain positron emission tomography (PET), motion tracking-based unrestrained awake rat brain imaging is being developed. In this paper, we propose a fast and accurate rat headmotion tracking method based on small PET point sources. PET point sources (3-4) attached to the rat's head are tracked in image space using 15-32-ms time frames. Our point source tracking (PST) method was validated using a manually moved microDerenzo phantom that was simultaneously tracked with an optical tracker (OT) for comparison. The PST method was further validated in three awake [ 18 F]FDG rat brain scans. Compared with the OT, the PST-based correction at the same frame rate (31.2 Hz) reduced the reconstructed FWHM by 0.39-0.66 mm for the different tested rod sizes of the microDerenzo phantom. The FWHM could be further reduced by another 0.07-0.13 mm when increasing the PST frame rate (66.7 Hz). Regional brain [ 18 F]FDG uptake in the motion corrected scan was strongly correlated ( ) with that of the anesthetized reference scan for all three cases ( ). The proposed PST method allowed excellent and reproducible motion correction in awake in vivo experiments. In addition, there is no need of specialized tracking equipment or additional calibrations to be performed, the point sources are practically imperceptible to the rat, and PST is ideally suitable for small bore scanners, where optical tracking might be challenging.

Electromagnetic servoing-a new tracking paradigm.

Science.gov (United States)

Reichl, Tobias; Gardiazabal, José; Navab, Nassir

2013-08-01

Electromagnetic (EM) tracking is highly relevant for many computer assisted interventions. This is in particular due to the fact that the scientific community has not yet developed a general solution for tracking of flexible instruments within the human body. Electromagnetic tracking solutions are highly attractive for minimally invasive procedures, since they do not require line of sight. However, a major problem with EM tracking solutions is that they do not provide uniform accuracy throughout the tracking volume and the desired, highest accuracy is often only achieved close to the center of tracking volume. In this paper, we present a solution to the tracking problem, by mounting an EM field generator onto a robot arm. Proposing a new tracking paradigm, we take advantage of the electromagnetic tracking to detect the sensor within a specific sub-volume, with known and optimal accuracy. We then use the more accurate and robust robot positioning for obtaining uniform accuracy throughout the tracking volume. Such an EM servoing methodology guarantees optimal and uniform accuracy, by allowing us to always keep the tracked sensor close to the center of the tracking volume. In this paper, both dynamic accuracy and accuracy distribution within the tracking volume are evaluated using optical tracking as ground truth. In repeated evaluations, the proposed method was able to reduce the overall error from 6.64±7.86 mm to a significantly improved accuracy of 3.83±6.43 mm. In addition, the combined system provides a larger tracking volume, which is only limited by the reach of the robot and not the much smaller tracking volume defined by the magnetic field generator.

An energy and direction independent fast neutron dosemeter based on electrochemically etched CR-39 nuclear track detectors

International Nuclear Information System (INIS)

James, K.; Matiullah; Durrani, S.A.

1987-01-01

A computer-based model is presented, which simulates the dose equivalent response of electrochemically etched CR-39 to fast neutrons of various energies and angles of incidence. Most previous calculations of the response of CR-39 have neglected the production of recoiling oxygen and carbon nuclei as well as α particles in the CR-39. We calculate that these 'heavy recoils' and α particles are the major source of electrochemically etchable tracks in bare CR-39 at neutron energies above approx. 2 MeV under typical etching conditions. Our calculations have been extended to predict the response of CR-39 used in conjunction with various combinations of polymeric front radiators and we have determined the radiator stack configuration with produces the most energy independent response. Again, the heavy recoils and α particles cannot be neglected and, for energies above approx. 2 MeV, these produce typically about 20% of the total response of our optimum stack. This type of fast neutron dosemeter is, however, strongly direction dependent. We have integrated the response over all appropriate angles to predict the dose equivalent response for two representative neutron fields, and we suggest a method for minimising the angular dependence. (author)

A Leader-path-following formation system for AGVs with multi-sensor data fusion based vehicle tracking

Science.gov (United States)

Yao, Wen; Zhao, Xijun; Yu, Yufeng; Fang, Yongkun; Wang, Chao; Yang, Tianfu

2017-09-01

Caravans composed of vehicles with different functionality or trafficability raise the demand that formation system structure shall allow vehicles to deviate from the path to be followed when necessary. In this paper, a formation system is developed for autonomous ground vehicles (AGVs) who follow the path of a leader vehicle while retaining the ability of deviation from the reference path. In addition, it improves robustness of preceding vehicle localization by fusing Lidar tracking, camera tracking results with predecessor’s global position within an extended Kalman filter (EKF) in case that one or more sources of preceding vehicle localization is not reliable. The system is applied on real AGV platforms and won the 3rd place in an AGV competition in China.

How Far Can Extended Knowledge Be Extended?

DEFF Research Database (Denmark)

Wray, K. Brad

2018-01-01

by an artifact, like a notebook or telescope. The chapter illustrates this by applying Pritchard’s account of extended knowledge to collaborating scientists. The beliefs acquired through collaborative research cannot satisfy both of Pritchard’s conditions of creditability. Further, there is evidence......Duncan Pritchard (2010) has developed a theory of extended knowledge based on the notion of extended cognition initially developed by Clark and Chalmers (1998). Pritchard’s account gives a central role to the notion of creditability, which requires the following two conditions to be met: (i...... that scientists are not prepared to take responsibility for the actions of the scientists with whom they collaborate....

Tracking the follow-up of work in progress papers.

Science.gov (United States)

Mubin, Omar; Arsalan, Mudassar; Al Mahmud, Abdullah

2018-01-01

Academic conferences offer numerous submission tracks to support the inclusion of a variety of researchers and topics. Work in progress papers are one such submission type where authors present preliminary results in a poster session. They have recently gained popularity in the area of Human Computer Interaction (HCI) as a relatively easier pathway to attending the conference due to their higher acceptance rate as compared to the main tracks. However, it is not clear if these work in progress papers are further extended or transitioned into more complete and thorough full papers or are simply one-off pieces of research. In order to answer this we explore self-citation patterns of four work in progress editions in two popular HCI conferences (CHI2010, CHI2011, HRI2010 and HRI2011). Our results show that almost 50% of the work in progress papers do not have any self-citations and approximately only half of the self-citations can be considered as true extensions of the original work in progress paper. Specific conferences dominate as the preferred venue where extensions of these work in progress papers are published. Furthermore, the rate of self-citations peaks in the immediate year after publication and gradually tails off. By tracing author publication records, we also delve into possible reasons of work in progress papers not being cited in follow up publications. In conclusion, we speculate on the main trends observed and what they may mean looking ahead for the work in progress track of premier HCI conferences.

Persistent Aerial Tracking

KAUST Repository

Mueller, Matthias

2016-01-01

persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc

MO-FG-BRD-02: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: MV Tracking

Energy Technology Data Exchange (ETDEWEB)

Berbeco, R. [Brigham and Women’s Hospital and Dana-Farber Cancer Institute (United States)

2015-06-15

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow.

MO-FG-BRD-04: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: MR Tracking

Energy Technology Data Exchange (ETDEWEB)

Low, D. [University of California Los Angeles: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: MR Tracking (United States)

2015-06-15

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow.

MO-FG-BRD-03: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: EM Tracking

Energy Technology Data Exchange (ETDEWEB)

Keall, P. [University of Sydney (Australia)

2015-06-15

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow.

MO-FG-BRD-04: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: MR Tracking

International Nuclear Information System (INIS)

Low, D.

2015-01-01

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow

MO-FG-BRD-03: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: EM Tracking

International Nuclear Information System (INIS)

Keall, P.

2015-01-01

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow

MO-FG-BRD-02: Real-Time Imaging and Tracking Techniques for Intrafractional Motion Management: MV Tracking

International Nuclear Information System (INIS)

Berbeco, R.

2015-01-01

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam-level imaging of radio-opaque fiducials, fiducial-less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real-time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam-level kilovoltage X-ray imaging techniques, 2) EPID-based megavoltage X-ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI-based soft-tissue tracking during radiation delivery. Learning Objectives: Understand the fundamentals of real-time imaging and tracking techniques Learn about emerging techniques in the field of real-time tracking Distinguish between the advantages and disadvantages of different tracking modalities Understand the role of real-time tracking techniques within the clinical delivery work-flow

Gaussian mixture probability hypothesis density filter for multipath multitarget tracking in over-the-horizon radar

Science.gov (United States)

Qin, Yong; Ma, Hong; Chen, Jinfeng; Cheng, Li

2015-12-01

Conventional multitarget tracking systems presume that each target can produce at most one measurement per scan. Due to the multiple ionospheric propagation paths in over-the-horizon radar (OTHR), this assumption is not valid. To solve this problem, this paper proposes a novel tracking algorithm based on the theory of finite set statistics (FISST) called the multipath probability hypothesis density (MP-PHD) filter in cluttered environments. First, the FISST is used to derive the update equation, and then Gaussian mixture (GM) is introduced to derive the closed-form solution of the MP-PHD filter. Moreover, the extended Kalman filter (EKF) is presented to deal with the nonlinear problem of the measurement model in OTHR. Eventually, the simulation results are provided to demonstrate the effectiveness of the proposed filter.

Surface effect of KrF laser exposure on ECE of alpha particle tracks in polycarbonate polymer

Energy Technology Data Exchange (ETDEWEB)

Parvin, P. [Physics Department, Amirkabir University, P.O. Box 15875-4413, Hafez Ave, Tehran (Iran, Islamic Republic of) and Laser Research Center, Atomic Energy Organization of Iran, AEOI, Tehran (Iran, Islamic Republic of)]. E-mail: parvin@aut.ac.ir; Jaleh, B. [Physics Department, Bu Ali Sina University, Hamadan (Iran, Islamic Republic of); Sheikh, N. [Gamma Irradiation Center, AEOI, Tehran (Iran, Islamic Republic of); Amiri, N. [Physics Department, Emam Hossien University, Tehran (Iran, Islamic Republic of)

2005-11-15

The optical penetration depth for polycarbonate (PC) at 308nm due to XeCl laser is about 450{mu}m while those of KrF (248nm) and ArF (193nm) lasers become noticeably shorter to 1{mu}m and 20nm, respectively, to show the strong superficial absorption at shorter UV wavelengths. On the other hand, KrF laser exposure on polycarbonate, at doses above 6J/cm{sup 2}, creates the surface crosslinking. In spite of several reliable methods available, such as 'hot set' and 'gel content', to determine the bulk crosslinking, there are a few consistent techniques to evaluate the surface crosslinking effect quantitatively. It includes hardening measurements using nanoindenter or AFM (atomic force microscopy). In this work, we present a technique for the measurement of superficial crosslinking, based on electrochemical etching of alpha irradiated polycarbonate accordingly. The mean diameter of the developed tracks nonlinearly decreases for KrF laser treatment at higher doses. The relative shrinkage of track diameters due to UV exposure before alpha irradiation, comparing to those without UV pre-radiation, indicates that UV laser makes the polymer surface hardened. The variation of mean track diameters can be strongly used to quantify the surface crosslinking.

Surface effect of KrF laser exposure on ECE of alpha particle tracks in polycarbonate polymer

International Nuclear Information System (INIS)

Parvin, P.; Jaleh, B.; Sheikh, N.; Amiri, N.

2005-01-01

The optical penetration depth for polycarbonate (PC) at 308nm due to XeCl laser is about 450μm while those of KrF (248nm) and ArF (193nm) lasers become noticeably shorter to 1μm and 20nm, respectively, to show the strong superficial absorption at shorter UV wavelengths. On the other hand, KrF laser exposure on polycarbonate, at doses above 6J/cm 2 , creates the surface crosslinking. In spite of several reliable methods available, such as 'hot set' and 'gel content', to determine the bulk crosslinking, there are a few consistent techniques to evaluate the surface crosslinking effect quantitatively. It includes hardening measurements using nanoindenter or AFM (atomic force microscopy). In this work, we present a technique for the measurement of superficial crosslinking, based on electrochemical etching of alpha irradiated polycarbonate accordingly. The mean diameter of the developed tracks nonlinearly decreases for KrF laser treatment at higher doses. The relative shrinkage of track diameters due to UV exposure before alpha irradiation, comparing to those without UV pre-radiation, indicates that UV laser makes the polymer surface hardened. The variation of mean track diameters can be strongly used to quantify the surface crosslinking

Entanglement across extended random defects in the XX spin chain

Science.gov (United States)

Juhász, Róbert

2017-08-01

We study the half-chain entanglement entropy in the ground state of the spin-1/2 XX chain across an extended random defect, where the strength of disorder decays with the distance from the interface algebraically as Δ_l∼ l-κ . In the whole regime κ≥slant 0 , the average entanglement entropy is found to increase logarithmically with the system size L as S_L≃\\frac{c_eff(κ)}{6}\\ln L+const , where the effective central charge c_eff(κ) depends on κ. In the regime κ<1/2 , where the extended defect is a relevant perturbation, the strong-disorder renormalization group method gives c_eff(κ)=(1-2κ)\\ln2 , while, in the regime κ≥slant 1/2 , where the extended defect is irrelevant in the bulk, numerical results indicate a non-zero effective central charge, which increases with κ. The variation of c_eff(κ) is thus found to be non-monotonic and discontinuous at κ=1/2 .

Tracks: A National Environmental Public Health Tracking Network Overview

Centers for Disease Control (CDC) Podcasts

2009-08-04

In this podcast, Dr. Mike McGeehin, Director of CDC's Division of Environmental Hazards and Health Effects, provides an overview of the National Environmental Public Health Tracking Network. It highlights the Tracking Network's goal, how it will improve public health, its audience, and much more.  Created: 8/4/2009 by Centers for Disease Control and Prevention (CDC).   Date Released: 8/4/2009.

Why we are tracking

DEFF Research Database (Denmark)

Tække, Jesper

2015-01-01

In this short essay, concerning why we are tracking, I will try to frame tracking as an evolutionary developed skill that humans need to survive. From an evolutionary point zero life must reflect upon itself in regard to its surrounding world as a kind of societal self-synchronization in this reg......In this short essay, concerning why we are tracking, I will try to frame tracking as an evolutionary developed skill that humans need to survive. From an evolutionary point zero life must reflect upon itself in regard to its surrounding world as a kind of societal self......-synchronization in this regard (Spencer 1890, Luhmann 2000, Tække 2014, 2011). I was inspired by Jill Walker Rettberg’s book: “Seeing Ourselves through Technology” and her presentation at the seminar: “Tracking Culture” arranged by Anders Albrechtslund in Aarhus January 2015....

A solution of the strong CP problem in models with scalars

International Nuclear Information System (INIS)

Dimopoulos, S.

1979-01-01

A possible solution to the strong CP problem within the context of a Weinberg-Salam model with two Higgs fields coupled in a Peccei-Quinn symmetric fashion is pointed out. This is done by extending the colour group to a bigger simple group which is broken at some very high energy. The model contains a heavy axion. No old or new U(1) problem re-emerges. (Auth.)

Fractional energy states of strongly-interacting bosons in one dimension

DEFF Research Database (Denmark)

Zinner, Nikolaj Thomas; G. Volosniev, A.; V. Fedorov, D.

2014-01-01

We study two-component bosonic systems with strong inter-species and vanishing intra-species interactions. A new class of exact eigenstates is found with energies that are {\\it not} sums of the single-particle energies with wave functions that have the characteristic feature that they vanish over...... than three particles. The states can be probed using the same techniques that have recently been used for fermionic few-body systems in quasi-1D.......We study two-component bosonic systems with strong inter-species and vanishing intra-species interactions. A new class of exact eigenstates is found with energies that are {\\it not} sums of the single-particle energies with wave functions that have the characteristic feature that they vanish over...... extended regions of coordinate space. This is demonstrated in an analytically solvable model for three equal mass particles, two of which are identical bosons, which is exact in the strongly-interacting limit. We numerically verify our results by presenting the first application of the stochastic...

SU-G-BRA-09: Estimation of Motion Tracking Uncertainty for Real-Time Adaptive Imaging

Energy Technology Data Exchange (ETDEWEB)

Yan, H [Capital Medical University, Beijing, Beijing (China); Chen, Z [Yale New Haven Hospital, New Haven, CT (United States); Nath, R; Liu, W [Yale University School of Medicine, New Haven, CT (United States)

2016-06-15

Purpose: kV fluoroscopic imaging combined with MV treatment beam imaging has been investigated for intrafractional motion monitoring and correction. It is, however, subject to additional kV imaging dose to normal tissue. To balance tracking accuracy and imaging dose, we previously proposed an adaptive imaging strategy to dynamically decide future imaging type and moments based on motion tracking uncertainty. kV imaging may be used continuously for maximal accuracy or only when the position uncertainty (probability of out of threshold) is high if a preset imaging dose limit is considered. In this work, we propose more accurate methods to estimate tracking uncertainty through analyzing acquired data in real-time. Methods: We simulated motion tracking process based on a previously developed imaging framework (MV + initial seconds of kV imaging) using real-time breathing data from 42 patients. Motion tracking errors for each time point were collected together with the time point’s corresponding features, such as tumor motion speed and 2D tracking error of previous time points, etc. We tested three methods for error uncertainty estimation based on the features: conditional probability distribution, logistic regression modeling, and support vector machine (SVM) classification to detect errors exceeding a threshold. Results: For conditional probability distribution, polynomial regressions on three features (previous tracking error, prediction quality, and cosine of the angle between the trajectory and the treatment beam) showed strong correlation with the variation (uncertainty) of the mean 3D tracking error and its standard deviation: R-square = 0.94 and 0.90, respectively. The logistic regression and SVM classification successfully identified about 95% of tracking errors exceeding 2.5mm threshold. Conclusion: The proposed methods can reliably estimate the motion tracking uncertainty in real-time, which can be used to guide adaptive additional imaging to confirm the

SU-G-BRA-09: Estimation of Motion Tracking Uncertainty for Real-Time Adaptive Imaging

International Nuclear Information System (INIS)

Yan, H; Chen, Z; Nath, R; Liu, W

2016-01-01

Purpose: kV fluoroscopic imaging combined with MV treatment beam imaging has been investigated for intrafractional motion monitoring and correction. It is, however, subject to additional kV imaging dose to normal tissue. To balance tracking accuracy and imaging dose, we previously proposed an adaptive imaging strategy to dynamically decide future imaging type and moments based on motion tracking uncertainty. kV imaging may be used continuously for maximal accuracy or only when the position uncertainty (probability of out of threshold) is high if a preset imaging dose limit is considered. In this work, we propose more accurate methods to estimate tracking uncertainty through analyzing acquired data in real-time. Methods: We simulated motion tracking process based on a previously developed imaging framework (MV + initial seconds of kV imaging) using real-time breathing data from 42 patients. Motion tracking errors for each time point were collected together with the time point’s corresponding features, such as tumor motion speed and 2D tracking error of previous time points, etc. We tested three methods for error uncertainty estimation based on the features: conditional probability distribution, logistic regression modeling, and support vector machine (SVM) classification to detect errors exceeding a threshold. Results: For conditional probability distribution, polynomial regressions on three features (previous tracking error, prediction quality, and cosine of the angle between the trajectory and the treatment beam) showed strong correlation with the variation (uncertainty) of the mean 3D tracking error and its standard deviation: R-square = 0.94 and 0.90, respectively. The logistic regression and SVM classification successfully identified about 95% of tracking errors exceeding 2.5mm threshold. Conclusion: The proposed methods can reliably estimate the motion tracking uncertainty in real-time, which can be used to guide adaptive additional imaging to confirm the

Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei

International Nuclear Information System (INIS)

Pillet, N.; Sandulescu, N.; Schuck, P.

2007-01-01

With realistic HFB calculations, using the D1S Gogny force, we reveal a generic behavior of concentration of small sized Cooper pairs (2-3 fm) in the surface of superfluid nuclei. This study confirms and extends previous results given in the literature that use more schematic approaches. It is shown that the strong concentration of pair probability of small Cooper pairs in the nuclear surface is a quite general and generic feature and that nuclear pairing is much closer to the strong coupling regime than previously assumed

Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei

Energy Technology Data Exchange (ETDEWEB)

Pillet, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France); Sandulescu, N. [DPTA/Service de Physique nucleaire, CEA/DAM Ile de France, BP12, F-91680 Bruyeres-le-Chatel (France)]|[Institute of Physics and Nuclear Engineering, 76900 Bucharest (Romania)]|[Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France); Schuck, P. [Institut de Physique Nucleaire, CNRS, UMR 8608, Orsay, F-91406 (France)]|[Universite Paris-Sud, Orsay, F-91505 (France)

2007-01-15

With realistic HFB calculations, using the D1S Gogny force, we reveal a generic behavior of concentration of small sized Cooper pairs (2-3 fm) in the surface of superfluid nuclei. This study confirms and extends previous results given in the literature that use more schematic approaches. It is shown that the strong concentration of pair probability of small Cooper pairs in the nuclear surface is a quite general and generic feature and that nuclear pairing is much closer to the strong coupling regime than previously assumed.

The DOe Silicon Track Trigger

International Nuclear Information System (INIS)

Steinbrueck, Georg

2003-01-01

We describe a trigger preprocessor to be used by the DOe experiment for selecting events with tracks from the decay of long-lived particles. This Level 2 impact parameter trigger utilizes information from the Silicon Microstrip Tracker to reconstruct tracks with improved spatial and momentum resolutions compared to those obtained by the Level 1 tracking trigger. It is constructed of VME boards with much of the logic existing in programmable processors. A common motherboard provides the I/O infrastructure and three different daughter boards perform the tasks of identifying the roads from the tracking trigger data, finding the clusters in the roads in the silicon detector, and fitting tracks to the clusters. This approach provides flexibility for the design, testing and maintenance phases of the project. The track parameters are provided to the trigger framework in 25 μs. The effective impact parameter resolution for high-momentum tracks is 35 μm, dominated by the size of the Tevatron beam

TO THE MODELING ISSUES OF LIFE CYCLE OF DEFORMATION WORK OF THE RAILWAY TRACK ELEMENTS

Directory of Open Access Journals (Sweden)

I. O. Bondarenko

2014-12-01

process of the railway track is prepared and assayed, but also its consequences. In addition, such models are flat, that also adds some complexity to compare the results with the experiment, since the process is not easy to distinguish the bulk of its limited influence in parts. The application of numerical methods extends the capabilities, and makes it impossible to consider the dynamic process, because it is impossible to introduce the processes that govern the response to the load. Therefore, the proposed modeling makes it possible to examine directly the dynamic process and evaluate the process due to the new criterion, the operational cycle of the strain gauge.

Fast Compressive Tracking.

Science.gov (United States)

Zhang, Kaihua; Zhang, Lei; Yang, Ming-Hsuan

2014-10-01

It is a challenging task to develop effective and efficient appearance models for robust object tracking due to factors such as pose variation, illumination change, occlusion, and motion blur. Existing online tracking algorithms often update models with samples from observations in recent frames. Despite much success has been demonstrated, numerous issues remain to be addressed. First, while these adaptive appearance models are data-dependent, there does not exist sufficient amount of data for online algorithms to learn at the outset. Second, online tracking algorithms often encounter the drift problems. As a result of self-taught learning, misaligned samples are likely to be added and degrade the appearance models. In this paper, we propose a simple yet effective and efficient tracking algorithm with an appearance model based on features extracted from a multiscale image feature space with data-independent basis. The proposed appearance model employs non-adaptive random projections that preserve the structure of the image feature space of objects. A very sparse measurement matrix is constructed to efficiently extract the features for the appearance model. We compress sample images of the foreground target and the background using the same sparse measurement matrix. The tracking task is formulated as a binary classification via a naive Bayes classifier with online update in the compressed domain. A coarse-to-fine search strategy is adopted to further reduce the computational complexity in the detection procedure. The proposed compressive tracking algorithm runs in real-time and performs favorably against state-of-the-art methods on challenging sequences in terms of efficiency, accuracy and robustness.

Tracking the global footprint of fisheries

Science.gov (United States)

Kroodsma, David A.; Mayorga, Juan; Hochberg, Timothy; Miller, Nathan A.; Boerder, Kristina; Ferretti, Francesco; Wilson, Alex; Bergman, Bjorn; White, Timothy D.; Block, Barbara A.; Woods, Paul; Sullivan, Brian; Costello, Christopher; Worm, Boris

2018-02-01

Although fishing is one of the most widespread activities by which humans harvest natural resources, its global footprint is poorly understood and has never been directly quantified. We processed 22 billion automatic identification system messages and tracked >70,000 industrial fishing vessels from 2012 to 2016, creating a global dynamic footprint of fishing effort with spatial and temporal resolution two to three orders of magnitude higher than for previous data sets. Our data show that industrial fishing occurs in >55% of ocean area and has a spatial extent more than four times that of agriculture. We find that global patterns of fishing have surprisingly low sensitivity to short-term economic and environmental variation and a strong response to cultural and political events such as holidays and closures.

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....

TrackingNet: A Large-Scale Dataset and Benchmark for Object Tracking in the Wild

KAUST Repository

Mü ller, Matthias; Bibi, Adel Aamer; Giancola, Silvio; Al-Subaihi, Salman; Ghanem, Bernard

2018-01-01

Despite the numerous developments in object tracking, further development of current tracking algorithms is limited by small and mostly saturated datasets. As a matter of fact, data-hungry trackers based on deep-learning currently rely on object detection datasets due to the scarcity of dedicated large-scale tracking datasets. In this work, we present TrackingNet, the first large-scale dataset and benchmark for object tracking in the wild. We provide more than 30K videos with more than 14 million dense bounding box annotations. Our dataset covers a wide selection of object classes in broad and diverse context. By releasing such a large-scale dataset, we expect deep trackers to further improve and generalize. In addition, we introduce a new benchmark composed of 500 novel videos, modeled with a distribution similar to our training dataset. By sequestering the annotation of the test set and providing an online evaluation server, we provide a fair benchmark for future development of object trackers. Deep trackers fine-tuned on a fraction of our dataset improve their performance by up to 1.6% on OTB100 and up to 1.7% on TrackingNet Test. We provide an extensive benchmark on TrackingNet by evaluating more than 20 trackers. Our results suggest that object tracking in the wild is far from being solved.

TrackingNet: A Large-Scale Dataset and Benchmark for Object Tracking in the Wild

KAUST Repository

Müller, Matthias

2018-03-28

Despite the numerous developments in object tracking, further development of current tracking algorithms is limited by small and mostly saturated datasets. As a matter of fact, data-hungry trackers based on deep-learning currently rely on object detection datasets due to the scarcity of dedicated large-scale tracking datasets. In this work, we present TrackingNet, the first large-scale dataset and benchmark for object tracking in the wild. We provide more than 30K videos with more than 14 million dense bounding box annotations. Our dataset covers a wide selection of object classes in broad and diverse context. By releasing such a large-scale dataset, we expect deep trackers to further improve and generalize. In addition, we introduce a new benchmark composed of 500 novel videos, modeled with a distribution similar to our training dataset. By sequestering the annotation of the test set and providing an online evaluation server, we provide a fair benchmark for future development of object trackers. Deep trackers fine-tuned on a fraction of our dataset improve their performance by up to 1.6% on OTB100 and up to 1.7% on TrackingNet Test. We provide an extensive benchmark on TrackingNet by evaluating more than 20 trackers. Our results suggest that object tracking in the wild is far from being solved.

Development of nuclear track detectors

International Nuclear Information System (INIS)

Somogyi, Gyoergy

1985-01-01

The birth and development of two decades of a new nuclear detection method is briefly summarized by one of the first inventors. The main steps of the development and broadening application of nuclear solid state track detectors are described underlying the contribution and main results of the research group of ATOMKI, Hungary (i.e. the finding of the proper plastic materials for track detectors, the discovery of correlations between the track diameter and the particle energy, the increasing of energy resolution, explanation of the track developing process, elaboration of new electrochemical track analyzing methods and automatic track analyzers). Recently, this detecting technique has grown to the phase of the industrial mass production and broad application in radiogeochemistry, mining, radioecology, personal monitoring in nuclear power plants, etc. (D.Gy.)

SU-D-18A-04: Quantifying the Ability of Tumor Tracking to Spare Normal Tissue

Energy Technology Data Exchange (ETDEWEB)

Burger, A; Buzurovic, I; Hurwitz, M; Williams, C; Lewis, J [Brigham and Women' s Hospital, Dana-Farber Cancer Center, Harvard Medical Sc, Boston, MA (United States); Mishra, P [Varian Medical Systems, Palo Alto, CA (United States); Seco, J [Mass General Hospital, Harvard Medical, Boston, MA (United States)

2014-06-01

Purpose: Tumor tracking allows for smaller tissue volumes to be treated, potentially reducing normal tissue damage. However, tumor tracking is a more complex treatment and has little benefit in some scenarios. Here we quantify the benefit of tumor tracking for a range of patients by estimating the dose of radiation to organs at risk and the normal tissue complication probability (NTCP) for both standard and tracking treatment plans. This comparison is performed using both patient 4DCT data and extended Cardiac-Torso (XCAT) digital phantoms. Methods: We use 4DCT data for 10 patients. Additionally, we generate digital phantoms with motion derived from measured patient long tumor trajectories to compare standard and tracking treatment plans. The standard treatment is based on the average intensity projection (AIP) of 4DCT images taken over a breath cycle. The tracking treatment is based on doses calculated on images representing the anatomy at each time point. It is assumed that there are no errors in tracking the target. The NTCP values are calculated based on RTOG guidelines. Results: The mean reduction in the mean dose delivered was 5.5% to the lungs (from 7.3 Gy to 6.9 Gy) and 4.0% to the heart (from 12.5 Gy to 12.0 Gy). The mean reduction in the max dose delivered was 13% to the spinal cord (from 27.6 Gy to 24.0 Gy), 2.5% to the carina (from 31.7 Gy to 30.9 Gy), and 15% to the esophagus (from 69.6 Gy to 58.9 Gy). The mean reduction in the probability of 2nd degree radiation pneumonitis (RP) was 8.7% (3.1% to 2.8%) and the mean reduction in the effective volume was 6.8% (10.8% to 10.2%). Conclusions: Tumor tracking has the potential to reduce irradiation of organs at risk, and consequentially reduce the normal tissue complication probability. The benefits vary based on the clinical scenario. This study is supported by Varian Medical Systems, Inc.

Expectations on Track? High School Tracking and Adolescent Educational Expectations

DEFF Research Database (Denmark)

Karlson, Kristian Bernt

2015-01-01

This paper examines the role of adaptation in expectation formation processes by analyzing how educational tracking in high schools affects adolescents' educational expectations. I argue that adolescents view track placement as a signal about their academic abilities and respond to it in terms...... of modifying their educational expectations. Applying a difference-in-differences approach to the National Educational Longitudinal Study of 1988, I find that being placed in an advanced or honors class in high school positively affects adolescents’ expectations, particularly if placement is consistent across...... subjects and if placement contradicts tracking experiences in middle school. My findings support the hypothesis that adolescents adapt their educational expectations to ability signals sent by schools....

Gravity model improvement using the DORIS tracking system on the SPOT 2 satellite

Science.gov (United States)

Nerem, R. S.; Lerch, F. J.; Williamson, R. G.; Klosko, S. M.; Robbins, J. W.; Patel, G. B.

1994-01-01

A high-precision radiometric satellite tracking system, Doppler Orbitography and Radio-positioning Integrated by Satellite system (DORIS), has recently been developed by the French space agency, Centre National d'Etudes Spatiales (CNES). DORIS was designed to provide tracking support for missions such as the joint United States/French TOPEX/Poseidon. As part of the flight testing process, a DORIS package was flown on the French SPOT 2 satellite. A substantial quantity of geodetic quality tracking data was obtained on SPOT 2 from an extensive international DORIS tracking network. These data were analyzed to assess their accuracy and to evaluate the gravitational modeling enhancements provided by these data in combination with the Goddard Earth Model-T3 (GEM-T3) gravitational model. These observations have noise levels of 0.4 to 0.5 mm/s, with few residual systematic effects. Although the SPOT 2 satellite experiences high atmospheric drag forces, the precision and global coverage of the DORIS tracking data have enabled more extensive orbit parameterization to mitigate these effects. As a result, the SPOT 2 orbital errors have been reduced to an estimated radial accuracy in the 10-20 cm RMS range. The addition of these data, which encompass many regions heretofore lacking in precision satellite tracking, has significantly improved GEM-T3 and allowed greatly improved orbit accuracies for Sun-synchronous satellites like SPOT 2 (such as ERS 1 and EOS). Comparison of the ensuing gravity model with other contemporary fields (GRIM-4C2, TEG2B, and OSU91A) provides a means to assess the current state of knowledge of the Earth's gravity field. Thus, the DORIS experiment on SPOT 2 has provided a strong basis for evaluating this new orbit tracking technology and has demonstrated the important contribution of the DORIS network to the success of the TOPEX/Poseidon mission.

Experimental Validation of Pulse Phase Tracking for X-Ray Pulsar Based

Science.gov (United States)

Anderson, Kevin

2012-01-01

the varying frequency case. This resulted in tracking of the phase and frequency by the DPLL outputs in both the simulation and experimental environments. The crab pulsar was experimentally tested with a trajectory with a higher acceleration. In this case the phase error tended toward zero as the observation extended to 250 seconds and the doppler frequency error tended to zero in under 100 seconds.

Self-Tracking: Reflections from the BodyTrack Project.

Science.gov (United States)

Wright, Anne

2016-07-06

Based on the author's experiences the practice of self-tracking can empower individuals to explore and address issues in their lives. This work is inspired by examples of people who have reclaimed their wellness through an iterative process of noticing patterns of ups and downs, trying out new ideas and strategies, and observing the results. In some cases, individuals have realized that certain foods, environmental exposures, or practices have unexpected effects for them, and that adopting custom strategies can greatly improve quality of life, overcoming chronic problems. Importantly, adopting the role of investigator of their own situation appears to be transformative: people who embarked on this path changed their relationship to their health situation even before making discoveries that helped lead to symptom improvement. The author co-founded the BodyTrack project in 2010 with the goal of empowering a broader set of people to embrace this investigator role in their own lives and better address their health and wellness concerns, particularly those with complex environmental or behavioral components. The core of the BodyTrack system is an open source web service called Fluxtream ( https://fluxtream.org ) that allows users to aggregate, visualize, and reflect on data from myriad sources on a common timeline. The project is also working to develop and spread peer coaching practices to help transfer the culture and skills of self-tracking while mentoring individuals in how to self-assess their own situation and guide the process for themselves.

Effect of Tracking Error of Double-Axis Tracking Device on the Optical Performance of Solar Dish Concentrator

Directory of Open Access Journals (Sweden)

Jian Yan

2018-01-01

Full Text Available In this paper, a flux distribution model of the focal plane in dish concentrator system has been established based on ray tracking method. This model was adopted for researching the influence of the mirror slope error, solar direct normal irradiance, and tracking error of elevation-azimuth tracking device (EATD on the focal spot characteristics (i.e., flux distribution, geometrical shape, centroid position, and intercept factor. The tracking error transmission law of the EATD transferred to dish concentrator was also studied. The results show that the azimuth tracking error of the concentrator decreases with the increase of the concentrator elevation angle and it decreases to 0 mrad when the elevation angle is 90°. The centroid position of focal spot along x-axis and y-axis has linear relationship with azimuth and elevation tracking error of EATD, respectively, which could be used to evaluate and calibrate the tracking error of the dish concentrator. Finally, the transmission law of the EATD azimuth tracking error in solar heliostats is analyzed, and a dish concentrator using a spin-elevation tracking device is proposed, which can reduce the effect of spin tracking error on the dish concentrator. This work could provide fundamental for manufacturing precision allocation of tracking devices and developing a new type of tracking device.

Tracking control of WMRs on loose soil based on mixed H2/H∞ control with longitudinal slip ratio estimation

Science.gov (United States)

Gao, Haibo; Chen, Chao; Ding, Liang; Li, Weihua; Yu, Haitao; Xia, Kerui; Liu, Zhen

2017-11-01

Wheeled mobile robots (WMRs) often suffer from the longitudinal slipping when moving on the loose soil of the surface of the moon during exploration. Longitudinal slip is the main cause of WMRs' delay in trajectory tracking. In this paper, a nonlinear extended state observer (NESO) is introduced to estimate the longitudinal velocity in order to estimate the slip ratio and the derivative of the loss of velocity which are used in modelled disturbance compensation. Owing to the uncertainty and disturbance caused by estimation errors, a multi-objective controller using the mixed H2/H∞ method is employed to ensure the robust stability and performance of the WMR system. The final inputs of the trajectory tracking consist of the feedforward compensation, compensation for the modelled disturbances and designed multi-objective control inputs. Finally, the simulation results demonstrate the effectiveness of the controller, which exhibits a satisfactory tracking performance.

ANNOTATION SUPPORTED OCCLUDED OBJECT TRACKING

Directory of Open Access Journals (Sweden)

Devinder Kumar

2012-08-01

Full Text Available Tracking occluded objects at different depths has become as extremely important component of study for any video sequence having wide applications in object tracking, scene recognition, coding, editing the videos and mosaicking. The paper studies the ability of annotation to track the occluded object based on pyramids with variation in depth further establishing a threshold at which the ability of the system to track the occluded object fails. Image annotation is applied on 3 similar video sequences varying in depth. In the experiment, one bike occludes the other at a depth of 60cm, 80cm and 100cm respectively. Another experiment is performed on tracking humans with similar depth to authenticate the results. The paper also computes the frame by frame error incurred by the system, supported by detailed simulations. This system can be effectively used to analyze the error in motion tracking and further correcting the error leading to flawless tracking. This can be of great interest to computer scientists while designing surveillance systems etc.

Why tracks

International Nuclear Information System (INIS)

Burchart, J.; Kral, J.

1979-01-01

A comparison is made of two methods of determining the age of rocks, ie., the krypton-argon method and the fission tracks method. The former method is more accurate but is dependent on the temperature and on the grain size of the investigated rocks (apatites, biotites, muscovites). As for the method of fission tracks, the determination is not dependent on grain size. This method allows dating and the determination of uranium concentration and distribution in rocks. (H.S.)

Pennsylvania Source Term Tracking System

International Nuclear Information System (INIS)

1992-08-01

The Pennsylvania Source Term Tracking System tabulates surveys received from radioactive waste generators in the Commonwealth of radioactive waste is collected each quarter from generators using the Low-Level Radioactive Waste Management Quarterly Report Form (hereafter called the survey) and then entered into the tracking system data base. This personal computer-based tracking system can generate 12 types of tracking reports. The first four sections of this reference manual supply complete instructions for installing and setting up the tracking system on a PC. Section 5 presents instructions for entering quarterly survey data, and Section 6 discusses generating reports. The appendix includes samples of each report

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.

Extended inflation with nonminimally coupled inflation field

International Nuclear Information System (INIS)

Panchapakesan, N.; Sethi, S.K.

1992-01-01

In this paper, an extended inflation model, in which the inflation field is nonminimally coupled to the gravity, is discussed. It is shown that the nucleation rate of bubbles, during a phase transition in the inflaton field, can increase as the transition proceeds for a wide range of parameters of the inflaton potential. The bounce action for three possible cases - the strong gravity regime, the thick-walled Coleman-DeLuccia bubbles and the thin-walled bubbles - is evaluated. The resulting bubble distribution for all the cases is shown to be in conformity with cosmological constraints for ω < 500

Spacecraft Doppler tracking with possible violations of LLI and LPI: a theoretical modeling

International Nuclear Information System (INIS)

Deng Xue-Mei; Xie Yi

2014-01-01

Currently two-way and three-way spacecraft Doppler tracking techniques are widely used and play important roles in control and navigation of deep space missions. Starting from a one-way Doppler model, we extend the theory to two-way and three-way Doppler models by making them include possible violations of the local Lorentz invariance (LLI) and the local position invariance (LPI) in order to test the Einstein equivalence principle, which is the cornerstone of general relativity and all other metric theories of gravity. After taking the finite speed of light into account, which is the so-called light time solution (LTS), we make these models depend on the time of reception of the signal only for practical convenience. We find that possible violations of LLI and LPI cannot affect two-way Doppler tracking under a linear approximation of LTS, although this approximation is sufficiently good for most cases in the solar system. We also show that, in three-way Doppler tracking, possible violations of LLI and LPI are only associated with two stations, which suggests that it is better to set the stations at places with significant differences in velocities and gravitational potentials to obtain a high level of sensitivity for the tests

Track segment synthesis method for NTA film

International Nuclear Information System (INIS)

Kumazawa, Shigeru

1980-03-01

A method is presented for synthesizing track segments extracted from a gray-level digital picture of NTA film in automatic counting system. In order to detect each track in an arbitrary direction, even if it has some gaps, as a set of the track segments, the method links extracted segments along the track, in succession, to the linked track segments, according to whether each extracted segment bears a similarity of direction to the track or not and whether it is connected with the linked track segments or not. In the case of a large digital picture, the method is applied to each subpicture, which is a strip of the picture, and then concatenates subsets of track segments linked at each subpicture as a set of track segments belonging to a track. The method was applied to detecting tracks in various directions over the eight 364 x 40-pixel subpictures with the gray scale of 127/pixel (picture element) of the microphotograph of NTA film. It was proved to be able to synthesize track segments correctly for every track in the picture. (author)

Tracks induced by swift heavy ions in semiconductors

International Nuclear Information System (INIS)

Szenes, G.; Horvath, Z.E.; Pecz, B.; Toth, L.; Paszti, F.

2002-01-01

InSb, GaSb, InP, InAs, and GaAs single crystals were irradiated with Pb ions in the range of 385-2170 MeV. The samples were studied by transmission and high-resolution electron microscopy and Rutherford backscattering in channeling geometry. The energetic ions induced isolated tracks in all crystals but GaAs. The thermal spike analysis revealed that the variation of the damage cross section with the ion energy is considerably weaker than in insulators. The widths of the thermal spike a(0) was estimated. The analysis was extended to recent C 60 experiments on Ge and Si. A quantitative relation was found between a(0) and the gap energy E g : a(0) is reduced with increasing E g , and its lowest value is close to that found in insulators

Multi-Color Single Particle Tracking with Quantum Dots

DEFF Research Database (Denmark)

Christensen, Eva Arnspang; Brewer, J. R.; Lagerholm, B. C.

2012-01-01

. multiplex single molecule sensitivity applications such as single particle tracking (SPT). In order to fully optimize single molecule multiplex application with QDs, we have in this work performed a comprehensive quantitative investigation of the fluorescence intensities, fluorescence intensity fluctuations......Quantum dots (QDs) have long promised to revolutionize fluorescence detection to include even applications requiring simultaneous multi-species detection at single molecule sensitivity. Despite the early promise, the unique optical properties of QDs have not yet been fully exploited in e. g...... further show that there is only a small size advantage in using blue-shifted QDs in biological applications because of the additional size of the water-stabilizing surface coat. Extending previous work, we finally also show that parallel four color multicolor (MC)-SPT with QDs is possible at an image...

Extended objects

International Nuclear Information System (INIS)

Creutz, M.

1976-01-01

After some disconnected comments on the MIT bag and string models for extended hadrons, I review current understanding of extended objects in classical conventional relativistic field theories and their quantum mechanical interpretation

Identification and tracking of low energy spectator protons

Energy Technology Data Exchange (ETDEWEB)

Mussgiller, A.

2007-07-20

The present theses discusses the development, technical design and realization as well as the read-out electronics of a detection system for the identification and tracking of low energy spectator protons. With the knowledge of the four-momentum of such spectator protons it will be possible to use deuterium as an effective neutron target. Previous measurements with an early version of the detection system have already shown that this method works quite well to investigate for instance the {omega} or {eta}-meson production in proton-neutron collisions. Moreover, after the completion and installation of the polarized internal target (PIT) at ANKE, it will be even possible to engage in that field with double polarized experiments. To increase the luminosity the polarized target is equipped with an extended target cell. The described detection-system will provide the vertex reconstruction for this extended interaction region. In addition, it will act as an independent beam polarimeter at ANKE. The detection system consists of three layers of double-sided silicon strip detectors which are arranged in a telescope structure and placed inside the accelerator vacuum as close as 2 cm to the interaction region. The modular design of the electronics and the support structures for the detectors allows one to exchange detectors and electronics in a maximum flexible way. In a minimum configuration the telescope is equipped with two detectors, a thin ({approx} 69 {mu}m) double-sided Silicon strip detector as a first layer and a very thick ({>=} 5 mm) double-sided micro-structured Lithium-drifted Silicon detector as a second layer. With this arrangement it is possible to track and identify protons in a kinetic energy range from 2.5 MeV to 25 MeV. For deuterons this range for such a telescope configuration is from 4 MeV to 34 MeV. The performance concerning the energy determination and tracking is shown based on data taken during a beam-time in November of 2003. With the existing

Identification and tracking of low energy spectator protons

International Nuclear Information System (INIS)

Mussgiller, A.

2007-01-01

The present theses discusses the development, technical design and realization as well as the read-out electronics of a detection system for the identification and tracking of low energy spectator protons. With the knowledge of the four-momentum of such spectator protons it will be possible to use deuterium as an effective neutron target. Previous measurements with an early version of the detection system have already shown that this method works quite well to investigate for instance the ω or η-meson production in proton-neutron collisions. Moreover, after the completion and installation of the polarized internal target (PIT) at ANKE, it will be even possible to engage in that field with double polarized experiments. To increase the luminosity the polarized target is equipped with an extended target cell. The described detection-system will provide the vertex reconstruction for this extended interaction region. In addition, it will act as an independent beam polarimeter at ANKE. The detection system consists of three layers of double-sided silicon strip detectors which are arranged in a telescope structure and placed inside the accelerator vacuum as close as 2 cm to the interaction region. The modular design of the electronics and the support structures for the detectors allows one to exchange detectors and electronics in a maximum flexible way. In a minimum configuration the telescope is equipped with two detectors, a thin (∼ 69 μm) double-sided Silicon strip detector as a first layer and a very thick (≥ 5 mm) double-sided micro-structured Lithium-drifted Silicon detector as a second layer. With this arrangement it is possible to track and identify protons in a kinetic energy range from 2.5 MeV to 25 MeV. For deuterons this range for such a telescope configuration is from 4 MeV to 34 MeV. The performance concerning the energy determination and tracking is shown based on data taken during a beam-time in November of 2003. With the existing setup an energy

General formula for on-axis sun-tracking system and its application in improving tracking accuracy of solar collector

Energy Technology Data Exchange (ETDEWEB)

Chong, K.K.; Wong, C.W. [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Off Jalan Genting Kelang, Setapak, 53300 Kuala Lumpur (Malaysia)

2009-03-15

Azimuth-elevation and tilt-roll tracking mechanism are among the most commonly used sun-tracking methods for aiming the solar collector towards the sun at all times. It has been many decades that each of these two sun-tracking methods has its own specific sun-tracking formula and they are not interrelated. In this paper, the most general form of sun-tracking formula that embraces all the possible on-axis tracking methods is presented. The general sun-tracking formula not only can provide a general mathematical solution, but more significantly it can improve the sun-tracking accuracy by tackling the installation error of the solar collector. (author)

Track finding and fitting in the H1 Forward Track Detector

International Nuclear Information System (INIS)

Burke, S.; Henderson, R.C.W.; Maxfield, S.J.; Patel, G.D.; Morris, J.V.; Sankey, D.P.C.; Skillicorn, I.O.

1995-07-01

The tracking environment in the H1 Forward Tracker Detector, where the hit multiplicity from proton fragments is high, is parituclarly hostile. The techniques and software which have been developed for pattern recognition and Kalman fitting of charged particle tracks in this region are described in detail. (orig.)

Impact of mesh tracks and low-ground-pressure vehicle use on blanket peat hydrology

Science.gov (United States)

McKendrick-Smith, Kathryn; Holden, Joseph; Parry, Lauren

2016-04-01

for directly under and close to the track. Where the track runs parallel to the contours, water-tables were found to be deeper downslope of the track and shallower upslope. However in the no track/driving treatment; water table was significantly shallower downslope than upslope. Strong anisotropy was found in both 'before-track' and 'after-track' Ks, with horizontal Ks significantly greater than vertical Ks. No significant difference was found in vertical Ks before and after driving (medians 8.6 x 10-5 and 6.6 x 10-5 cm s-1 respectively). Horizontal Ks was significantly greater after driving (median 2.2 x 10-3 cm s-1) than before (median 3.7 x 10-4 cm s-1). Post-hoc testing highlights variability in response to treatment and topographic position. We suggest that this surprising result is related to rapid regrowth of new vegetation (particularly Sphagnum) through the mesh of the track, which was more dominant on horizontal Ks than the compression from low-ground-pressure vehicle use. Our results indicate that mesh tracks have a significant impact upon hydrology; however response is variable dependent upon topographic and seasonal factors. These findings can be used to inform land-management decision-making for the use of mesh tracks in peatlands.

SimTrack: A compact c++ library for particle orbit and spin tracking in accelerators

Energy Technology Data Exchange (ETDEWEB)

Luo, Yun [Brookhaven National Laboratory (BNL), Upton, NY (United States)

2015-06-24

SimTrack is a compact c++ library of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam-beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam-beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam-beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

Energy Technology Data Exchange (ETDEWEB)

Luo, Yun

2015-11-21

SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this paper, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

Development and applications of single particle orientation and rotational tracking in dynamic systems

Energy Technology Data Exchange (ETDEWEB)

Chen, Kuangcai [Iowa State Univ., Ames, IA (United States)

2016-02-19

The goal of this study is to help with future data analysis and experiment designs in rotational dynamics research using DIC-based SPORT technique. Most of the current studies using DIC-based SPORT techniques are technical demonstrations. Understanding the mechanisms behind the observed rotational behaviors of the imaging probes should be the focus of the future SPORT studies. More efforts are still needed in the development of new imaging probes, particle tracking methods, instrumentations, and advanced data analysis methods to further extend the potential of DIC-based SPORT technique.

Mouse short- and long-term locomotor activity analyzed by video tracking software.

Science.gov (United States)

York, Jason M; Blevins, Neil A; McNeil, Leslie K; Freund, Gregory G

2013-06-20

Locomotor activity (LMA) is a simple and easily performed measurement of behavior in mice and other rodents. Improvements in video tracking software (VTS) have allowed it to be coupled to LMA testing, dramatically improving specificity and sensitivity when compared to the line crossings method with manual scoring. In addition, VTS enables high-throughput experimentation. While similar to automated video tracking used for the open field test (OFT), LMA testing is unique in that it allows mice to remain in their home cage and does not utilize the anxiogenic stimulus of bright lighting during the active phase of the light-dark cycle. Traditionally, LMA has been used for short periods of time (mins), while longer movement studies (hrs-days) have often used implanted transmitters and biotelemetry. With the option of real-time tracking, long-, like short-term LMA testing, can now be conducted using videography. Long-term LMA testing requires a specialized, but easily constructed, cage so that food and water (which is usually positioned on the cage top) does not obstruct videography. Importantly, videography and VTS allows for the quantification of parameters, such as path of mouse movement, that are difficult or unfeasible to measure with line crossing and/or biotelemetry. In sum, LMA testing coupled to VTS affords a more complete description of mouse movement and the ability to examine locomotion over an extended period of time.

Effective star tracking method based on optical flow analysis for star trackers.

Science.gov (United States)

Sun, Ting; Xing, Fei; Wang, Xiaochu; Li, Jin; Wei, Minsong; You, Zheng

2016-12-20

Benefiting from rapid development of imaging sensor technology, modern optical technology, and a high-speed computing chip, the star tracker's accuracy, dynamic performance, and update rate have been greatly improved with low power consumption and miniature size. The star tracker is currently one of the most competitive attitude measurement sensors. However, due to restrictions of the optical imaging system, difficulties still exist in moving star spot detection and star tracking when in special motion conditions. An effective star tracking method based on optical flow analysis for star trackers is proposed in this paper. Spot-based optical flow, based on a gray gradient between two adjacent star images, is analyzed to distinguish the star spot region and obtain an accurate star spot position so that the star tracking can keep continuous under high dynamic conditions. The obtained star vectors and extended Kalman filter (EKF) are then combined to conduct an angular velocity estimation to ensure region prediction of the star spot; this can be combined with the optical flow analysis result. Experiment results show that the method proposed in this paper has advantages in conditions of large angular velocity and large angular acceleration, despite the presence of noise. Higher functional density and better performance can be achieved; thus, the star tracker can be more widely applied in small satellites, remote sensing, and other complex space missions.

Tracking and Finding Slow-Proliferating/Quiescent Cancer Stem Cells with Fluorescent Nanodiamonds.

Science.gov (United States)

Lin, Hsin-Hung; Lee, Hsiao-Wen; Lin, Ruey-Jen; Huang, Chih-Wei; Liao, Yi-Chun; Chen, Yit-Tsong; Fang, Jim-Min; Lee, Te-Chang; Yu, Alice L; Chang, Huan-Cheng

2015-09-09

Quiescent cancer stem cells (CSCs) have long been considered to be a source of tumor initiation. However, identification and isolation of these cells have been hampered by the fact that commonly used fluorescent markers are not sufficiently stable, both chemically and photophysically, to allow tracking over an extended period of time. Here, it is shown that fluorescent nanodiamonds (FNDs) are well suited for this application. Genotoxicity tests of FNDs with comet and micronucleus assays for human fibroblasts and breast cancer cells indicate that the nanoparticles neither cause DNA damage nor impair cell growth. Using AS-B145-1R breast cancer cells as the model cell line for CSC, it is found that the FND labeling outperforms 5-ethynyl-2'-deoxyuridine (EdU) and carboxyfluorescein diacetate succinimidyl ester (CFSE) in regards to its long-term tracking capability (>20 d). Moreover, through a quantification of their stem cell activity by measuring mammosphere-forming efficiencies (MFEs) and self-renewal rates, the FND-positive cells are identified to have an MFE twice as high as that of the FND-negative cells isolated from the same dissociated mammospheres. Thus, the nanoparticle-based labeling technique provides an effective new tool for tracking and finding slow-proliferating/quiescent CSCs in cancer research. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biopsy Needle Localization and Tracking Using ROI-RK Method

Directory of Open Access Journals (Sweden)

Yue Zhao

2014-01-01

Full Text Available ROI-RK method is a biopsy needle localization and tracking method. Previous research work has proved that it has a robust performance on different series of simulated 3D US volumes. Unfortunately, in real situations, because of the strong speckle noise of the ultrasound image and the different echogenic properties of the tissues, the real 3D US volumes have more complex background than the simulated images used previously. In this paper, to adapt the ROI-RK method in real 3D US volumes, a line-filter enhancement calculation only in the ROI is added to increase the contrast between the needle and background tissue, decreasing the phenomenon of expansion of the biopsy needle due to reverberation of ultrasound in the needle. To make the ROI-RK method more stable, a self-correction system is also implemented. Real data have been acquired on an ex vivo heart of lamb. The result of the ROI-RK method shows that it is capable to localize and track the biopsy needle in real situations, and it satisfies the demand of real-time application.

Integrating out resonances in strongly-coupled electroweak scenarios

Directory of Open Access Journals (Sweden)

Rosell Ignasi

2017-01-01

Full Text Available Accepting that there is a mass gap above the electroweak scale, the Electroweak Effective Theory (EWET is an appropriate tool to describe this situation. Since the EWET couplings contain information on the unknown high-energy dynamics, we consider a generic strongly-coupled scenario of electroweak symmetry breaking, where the known particle fields are coupled to heavier states. Then, and by integrating out these heavy fields, we study the tracks of the lightest resonances into the couplings. The determination of the low-energy couplings (LECs in terms of resonance parameters can be made more precise by considering a proper short-distance behaviour on the Lagrangian with heavy states, since the number of resonance couplings is then reduced. Notice that we adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs.

NONLINEAR ESTIMATION METHODS FOR AUTONOMOUS TRACKED VEHICLE WITH SLIP