WorldWideScience

Sample records for light based tracking

  1. Liquid crystal TV-based white light optical tracking novelty filter.

    Science.gov (United States)

    Li, Y; Kostrzewski, A; Kim, D H; Eichmann, G

    1989-11-15

    A compact white light optical tracking novelty filter is demonstrated. Based on the use of two inexpensive liquid crystal televisions, a filtered and collimated white light source, digital delay, and video recorder, this portable white light device performs two major image comparison operations, a real time image subtraction and novelty tracking operations. Some preliminary experimental results are presented.

  2. Remote Marker-Based Tracking for UAV Landing Using Visible-Light Camera Sensor.

    Science.gov (United States)

    Nguyen, Phong Ha; Kim, Ki Wan; Lee, Young Won; Park, Kang Ryoung

    2017-08-30

    Unmanned aerial vehicles (UAVs), which are commonly known as drones, have proved to be useful not only on the battlefields where manned flight is considered too risky or difficult, but also in everyday life purposes such as surveillance, monitoring, rescue, unmanned cargo, aerial video, and photography. More advanced drones make use of global positioning system (GPS) receivers during the navigation and control loop which allows for smart GPS features of drone navigation. However, there are problems if the drones operate in heterogeneous areas with no GPS signal, so it is important to perform research into the development of UAVs with autonomous navigation and landing guidance using computer vision. In this research, we determined how to safely land a drone in the absence of GPS signals using our remote maker-based tracking algorithm based on the visible light camera sensor. The proposed method uses a unique marker designed as a tracking target during landing procedures. Experimental results show that our method significantly outperforms state-of-the-art object trackers in terms of both accuracy and processing time, and we perform test on an embedded system in various environments.

  3. Accuracy analysis for triangulation and tracking based on time-multiplexed structured light.

    Science.gov (United States)

    Wagner, Benjamin; Stüber, Patrick; Wissel, Tobias; Bruder, Ralf; Schweikard, Achim; Ernst, Floris

    2014-08-01

    The authors' research group is currently developing a new optical head tracking system for intracranial radiosurgery. This tracking system utilizes infrared laser light to measure features of the soft tissue on the patient's forehead. These features are intended to offer highly accurate registration with respect to the rigid skull structure by means of compensating for the soft tissue. In this context, the system also has to be able to quickly generate accurate reconstructions of the skin surface. For this purpose, the authors have developed a laser scanning device which uses time-multiplexed structured light to triangulate surface points. The accuracy of the authors' laser scanning device is analyzed and compared for different triangulation methods. These methods are given by the Linear-Eigen method and a nonlinear least squares method. Since Microsoft's Kinect camera represents an alternative for fast surface reconstruction, the authors' results are also compared to the triangulation accuracy of the Kinect device. Moreover, the authors' laser scanning device was used for tracking of a rigid object to determine how this process is influenced by the remaining triangulation errors. For this experiment, the scanning device was mounted to the end-effector of a robot to be able to calculate a ground truth for the tracking. The analysis of the triangulation accuracy of the authors' laser scanning device revealed a root mean square (RMS) error of 0.16 mm. In comparison, the analysis of the triangulation accuracy of the Kinect device revealed a RMS error of 0.89 mm. It turned out that the remaining triangulation errors only cause small inaccuracies for the tracking of a rigid object. Here, the tracking accuracy was given by a RMS translational error of 0.33 mm and a RMS rotational error of 0.12°. This paper shows that time-multiplexed structured light can be used to generate highly accurate reconstructions of surfaces. Furthermore, the reconstructed point sets can be

  4. Track structure based modelling of light ion radiation effects on nuclear and mitochondrial DNA

    Science.gov (United States)

    Schmitt, Elke; Ottolenghi, Andrea; Dingfelder, Michael; Friedland, Werner; Kundrat, Pavel; Baiocco, Giorgio

    2016-07-01

    Space radiation risk assessment is of great importance for manned spaceflights in order to estimate risks and to develop counter-measures to reduce them. Biophysical simulations with PARTRAC can help greatly to improve the understanding of initial biological response to ionizing radiation. Results from modelling radiation quality dependent DNA damage and repair mechanisms up to chromosomal aberrations (e.g. dicentrics) can be used to predict radiation effects depending on the kind of mixed radiation field exposure. Especially dicentric yields can serve as a biomarker for an increased risk due to radiation and hence as an indicator for the effectiveness of the used shielding. PARTRAC [1] is a multi-scale biophysical research MC code for track structure based initial DNA damage and damage response modelling. It integrates physics, radiochemistry, detailed nuclear DNA structure and molecular biology of DNA repair by NHEJ-pathway to assess radiation effects on cellular level [2]. Ongoing experiments with quasi-homogeneously distributed compared to sub-micrometre focused bunches of protons, lithium and carbon ions allow a separation of effects due to DNA damage complexity on nanometre scale from damage clustering on (sub-) micrometre scale [3, 4]. These data provide an unprecedented benchmark for the DNA damage response model in PARTRAC and help understand the mechanisms leading to cell killing and chromosomal aberrations (e.g. dicentrics) induction. A large part of space radiation is due to a mixed ion field of high energy protons and few heavier ions that can be only partly absorbed by the shielding. Radiation damage induced by low-energy ions significantly contributes to the high relative biological efficiency (RBE) of ion beams around Bragg peak regions. For slow light ions the physical cross section data basis in PARTRAC has been extended to investigate radiation quality effects in the Bragg peak region [5]. The resulting range and LET values agree with ICRU data

  5. Quantitative analysis of signal transduction in motile and phototactic cells by computerized light stimulation and model based tracking

    Science.gov (United States)

    Streif, Stefan; Staudinger, Wilfried Franz; Oesterhelt, Dieter; Marwan, Wolfgang

    2009-02-01

    To investigate the responses of Halobacterium salinarum to stimulation with light (phototaxis and photokinesis), we designed an experimental setup consisting of optical devices for automatic video image acquisition and computer-controlled light stimulation, and developed algorithms to analyze physiological responses of the cells. Cells are categorized as motile and nonmotile by a classification scheme based on the square displacement of cell positions. Computerized tracking based on a dynamic model of the stochastic cell movement and a Kalman filter-based algorithm allows smoothed estimates of the cell tracks and the detection of physiological responses to complex stimulus patterns. The setup and algorithms were calibrated which allows quantitative measurements and systematic analysis of cellular sensing and response. Overall, the setup is flexible, extensible, and consists mainly of commercially available products. This facilitates modifications of the setup and algorithms for physiological studies of the motility of cells or microorganisms.

  6. Quantitative analysis of signal transduction in motile and phototactic cells by computerized light stimulation and model based tracking.

    Science.gov (United States)

    Streif, Stefan; Staudinger, Wilfried Franz; Oesterhelt, Dieter; Marwan, Wolfgang

    2009-02-01

    To investigate the responses of Halobacterium salinarum to stimulation with light (phototaxis and photokinesis), we designed an experimental setup consisting of optical devices for automatic video image acquisition and computer-controlled light stimulation, and developed algorithms to analyze physiological responses of the cells. Cells are categorized as motile and nonmotile by a classification scheme based on the square displacement of cell positions. Computerized tracking based on a dynamic model of the stochastic cell movement and a Kalman filter-based algorithm allows smoothed estimates of the cell tracks and the detection of physiological responses to complex stimulus patterns. The setup and algorithms were calibrated which allows quantitative measurements and systematic analysis of cellular sensing and response. Overall, the setup is flexible, extensible, and consists mainly of commercially available products. This facilitates modifications of the setup and algorithms for physiological studies of the motility of cells or microorganisms.

  7. Structured light-based motion tracking in the limited view of an MR head coil

    Energy Technology Data Exchange (ETDEWEB)

    Erikshøj, M., E-mail: martin@erikshoj.dk [DTU-Informatics, Technical University of Denmark (Denmark); Department of Clinical Physiology, Nuclear Medicine and PET, Righospitalet, University of Copenhagen (Denmark); Olesen, O.V. [DTU-Informatics, Technical University of Denmark (Denmark); Department of Clinical Physiology, Nuclear Medicine and PET, Righospitalet, University of Copenhagen (Denmark); Conradsen, K. [DTU-Informatics, Technical University of Denmark (Denmark); Højgaard, L. [Department of Clinical Physiology, Nuclear Medicine and PET, Righospitalet, University of Copenhagen (Denmark); Larsen, R. [DTU-Informatics, Technical University of Denmark (Denmark)

    2013-02-21

    A markerless motion tracking (MT) system developed for use in PET brain imaging has been tested in the limited field of view (FOV) of the MR head coil from the Siemens Biograph mMR. The system is a 3D surface scanner that uses structured light (SL) to create point cloud reconstructions of the facial surface. The point clouds are continuously realigned to a reference scan to obtain pose estimates. The system has been tested on a mannequin head performing controlled rotational and translational axial movements within the head coil outside the range of the magnetic field. The RMS of the residual error of the rotation was 0.11° and the RMS difference in the translation with the control system was 0.17 mm, within the trackable range of movement.

  8. Active tracking system for visible light communication using a GaN-based micro-LED and NRZ-OOK.

    Science.gov (United States)

    Lu, Zhijian; Tian, Pengfei; Chen, Hong; Baranowski, Izak; Fu, Houqiang; Huang, Xuanqi; Montes, Jossue; Fan, Youyou; Wang, Hongyi; Liu, Xiaoyan; Liu, Ran; Zhao, Yuji

    2017-07-24

    Visible light communication (VLC) holds the promise of a high-speed wireless network for indoor applications and competes with 5G radio frequency (RF) system. Although the breakthrough of gallium nitride (GaN) based micro-light-emitting-diodes (micro-LEDs) increases the -3dB modulation bandwidth exceptionally from tens of MHz to hundreds of MHz, the light collected onto a fast photo receiver drops dramatically, which determines the signal to noise ratio (SNR) of VLC. To fully implement the practical high data-rate VLC link enabled by a GaN-based micro-LED, it requires focusing optics and a tracking system. In this paper, we demonstrate an active on-chip tracking system for VLC using a GaN-based micro-LED and none-return-to-zero on-off keying (NRZ-OOK). Using this novel technique, the field of view (FOV) was enlarged to 120° and data rates up to 600 Mbps at a bit error rate (BER) of 2.1×10(-4) were achieved without manual focusing. This paper demonstrates the establishment of a VLC physical link that shows enhanced communication quality by orders of magnitude, making it optimized for practical communication applications.

  9. Image Tracking for the High Similarity Drug Tablets Based on Light Intensity Reflective Energy and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Zhongwei Liang

    2014-01-01

    Full Text Available It is obvious that tablet image tracking exerts a notable influence on the efficiency and reliability of high-speed drug mass production, and, simultaneously, it also emerges as a big difficult problem and targeted focus during production monitoring in recent years, due to the high similarity shape and random position distribution of those objectives to be searched for. For the purpose of tracking tablets accurately in random distribution, through using surface fitting approach and transitional vector determination, the calibrated surface of light intensity reflective energy can be established, describing the shape topology and topography details of objective tablet. On this basis, the mathematical properties of these established surfaces have been proposed, and thereafter artificial neural network (ANN has been employed for classifying those moving targeted tablets by recognizing their different surface properties; therefore, the instantaneous coordinate positions of those drug tablets on one image frame can then be determined. By repeating identical pattern recognition on the next image frame, the real-time movements of objective tablet templates were successfully tracked in sequence. This paper provides reliable references and new research ideas for the real-time objective tracking in the case of drug production practices.

  10. Motion Tracking for Medical Imaging: A Non-Visible Structured Light Tracking Approach

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte

    2012-01-01

    ) a customized version of this projector replacing a visible light LED with a 850 nm near infrared LED. The latter system does not provide additional discomfort by visible light projection into the patient’s eyes. The main advantage over existing head motion tracking devices, including the Polaris Vicra system......We present a system for head motion tracking in 3D brain imaging. The system is based on facial surface reconstruction and tracking using a structured light (SL) scanning principle. The system is designed to fit into narrow 3D medical scanner geometries limiting the field of view. It is tested...... in a clinical setting on the high resolution research tomograph (HRRT), Siemens PET scanner with a head phantom and volunteers. The SL system is compared to a commercial optical tracking system, the Polaris Vicra system, from NDI based on translatory and rotary ground truth motions of the head phantom...

  11. Motion tracking for medical imaging: a nonvisible structured light tracking approach.

    Science.gov (United States)

    Olesen, Oline Vinter; Paulsen, Rasmus R; Højgaard, Liselotte; Roed, Bjarne; Larsen, Rasmus

    2012-01-01

    We present a system for head motion tracking in 3D brain imaging. The system is based on facial surface reconstruction and tracking using a structured light (SL) scanning principle. The system is designed to fit into narrow 3D medical scanner geometries limiting the field of view. It is tested in a clinical setting on the high resolution research tomograph (HRRT), Siemens PET scanner with a head phantom and volunteers. The SL system is compared to a commercial optical tracking system, the Polaris Vicra system, from NDI based on translatory and rotary ground truth motions of the head phantom. The accuracy of the systems was similar, with root mean square (rms) errors of 0.09 degrees for ±20 degrees axial rotations, and rms errors of 0.24 mm for ± 25 mm translations. Tests were made using (1) a light emitting diode (LED) based miniaturized video projector, the Pico projector from Texas Instruments, and (2) a customized version of this projector replacing a visible light LED with a 850 nm near infrared LED. The latter system does not provide additional discomfort by visible light projection into the patient's eyes. The main advantage over existing head motion tracking devices, including the Polaris Vicra system, is that it is not necessary to place markers on the patient. This provides a simpler workflow and eliminates uncertainties related to marker attachment and stability. We show proof of concept of a marker less tracking system especially designed for clinical use with promising results.

  12. Motion tracking in narrow spaces: a structured light approach

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus; Højgaard, Liselotte

    2010-01-01

    We present a novel tracking system for patient head motion inside 3D medical scanners. Currently, the system is targeted at the Siemens High Resolution Research Tomograph (HRRT) PET scanner. Partial face surfaces are reconstructed using a miniaturized structured light system. The reconstructed 3D...... the system to a standard optical motion tracker based on a rigid tracking tool. Our system achieves an angular RMSE of 0.11 degrees demonstrating its relevance for motion compensated 3D scan image reconstructions as well as its competitiveness against the standard optical system with an RMSE of 0.08 degrees...

  13. Close-Range Tracking of Underwater Vehicles Using Light Beacons.

    Science.gov (United States)

    Bosch, Josep; Gracias, Nuno; Ridao, Pere; Istenič, Klemen; Ribas, David

    2016-03-25

    This paper presents a new tracking system for autonomous underwater vehicles (AUVs) navigating in a close formation, based on computer vision and the use of active light markers. While acoustic localization can be very effective from medium to long distances, it is not so advantageous in short distances when the safety of the vehicles requires higher accuracy and update rates. The proposed system allows the estimation of the pose of a target vehicle at short ranges, with high accuracy and execution speed. To extend the field of view, an omnidirectional camera is used. This camera provides a full coverage of the lower hemisphere and enables the concurrent tracking of multiple vehicles in different positions. The system was evaluated in real sea conditions by tracking vehicles in mapping missions, where it demonstrated robust operation during extended periods of time.

  14. Close-Range Tracking of Underwater Vehicles Using Light Beacons

    Science.gov (United States)

    Bosch, Josep; Gracias, Nuno; Ridao, Pere; Istenič, Klemen; Ribas, David

    2016-01-01

    This paper presents a new tracking system for autonomous underwater vehicles (AUVs) navigating in a close formation, based on computer vision and the use of active light markers. While acoustic localization can be very effective from medium to long distances, it is not so advantageous in short distances when the safety of the vehicles requires higher accuracy and update rates. The proposed system allows the estimation of the pose of a target vehicle at short ranges, with high accuracy and execution speed. To extend the field of view, an omnidirectional camera is used. This camera provides a full coverage of the lower hemisphere and enables the concurrent tracking of multiple vehicles in different positions. The system was evaluated in real sea conditions by tracking vehicles in mapping missions, where it demonstrated robust operation during extended periods of time. PMID:27023547

  15. Motion tracking in narrow spaces: a structured light approach.

    Science.gov (United States)

    Olesen, Oline Vinter; Paulsen, Rasmus R; Højgaar, Liselotte; Roed, Bjarne; Larsen, Rasmus

    2010-01-01

    We present a novel tracking system for patient head motion inside 3D medical scanners. Currently, the system is targeted at the Siemens High Resolution Research Tomograph (HRRT) PET scanner. Partial face surfaces are reconstructed using a miniaturized structured light system. The reconstructed 3D point clouds are matched to a reference surface using a robust iterative closest point algorithm. A main challenge is the narrow geometry requiring a compact structured light system and an oblique angle of observation. The system is validated using a mannequin head mounted on a rotary stage. We compare the system to a standard optical motion tracker based on a rigid tracking tool. Our system achieves an angular RMSE of 0.11 degrees demonstrating its relevance for motion compensated 3D scan image reconstructions as well as its competitiveness against the standard optical system with an RMSE of 0.08 degrees. Finally, we demonstrate qualitative result on real face motion estimation.

  16. Dual Axis Light Sensor for Tracking Sun

    Science.gov (United States)

    Shibata, Miki; Tambo, Toyokazu

    We have developed convenient light sensors to control a platform of solar cell panel. Dual axis light sensor in the present paper has structure of 5 PD (photodiode) light sensor which is composed of 5 photodiodes attached on a frustum of pyramid(1). Light source can be captured in front of the sensor by rotating the X and Y axis as decreasing the output deviation between two pairs of outside photodiodes. We here report the mechanism of sun tacking using the dual axis 5 PD light sensor and the fundamental results performed in the dark room.

  17. Graph Model Based Indoor Tracking

    DEFF Research Database (Denmark)

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

    2009-01-01

    The tracking of the locations of moving objects in large indoor spaces is important, as it enables a range of applications related to, e.g., security and indoor navigation and guidance. This paper presents a graph model based approach to indoor tracking that offers a uniform data management...... infrastructure for different symbolic positioning technologies, e.g., Bluetooth and RFID. More specifically, the paper proposes a model of indoor space that comprises a base graph and mappings that represent the topology of indoor space at different levels. The resulting model can be used for one or several...... indoor positioning technologies. Focusing on RFID-based positioning, an RFID specific reader deployment graph model is built from the base graph model. This model is then used in several algorithms for constructing and refining trajectories from raw RFID readings. Empirical studies with implementations...

  18. Motion tracking in narrow spaces: A structured light approach

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte

    2010-01-01

    We present a novel tracking system for patient head motion inside 3D medical scanners. Currently, the system is targeted at the Siemens High Resolution Research Tomograph (HRRT) PET scanner. Partial face surfaces are reconstructed using a miniaturized structured light system. The reconstructed 3D...

  19. Motion tracking in narrow spaces: a structured light approach

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus; Højgaard, Liselotte;

    2010-01-01

    We present a novel tracking system for patient head motion inside 3D medical scanners. Currently, the system is targeted at the Siemens High Resolution Research Tomograph (HRRT) PET scanner. Partial face surfaces are reconstructed using a miniaturized structured light system. The reconstructed 3D...

  20. Motion tracking in narrow spaces: A structured light approach

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte

    2010-01-01

    We present a novel tracking system for patient head motion inside 3D medical scanners. Currently, the system is targeted at the Siemens High Resolution Research Tomograph (HRRT) PET scanner. Partial face surfaces are reconstructed using a miniaturized structured light system. The reconstructed 3D...

  1. Using Light Scattering to Track, Characterize and Manipulate Colloids

    NARCIS (Netherlands)

    van Oostrum, P.D.J.

    2011-01-01

    A new technique is developed to analyze in-line Digital Holographic Microscopy images, making it possible to characterize, and track colloidal particles in three dimensions at unprecedented accuracy. We took digital snapshots of the interference pattern between the light scattered by micrometer

  2. Design of solar cell lighting and sun tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Khaing, A.A. [Mandalay Technological Univ., Mandalay (Myanmar); Ministry of Science, Yangon (Myanmar)

    2008-07-01

    A solar cell lighting and sun tracking system was discussed and the characteristics of solar cells were studied. An SM50H solar module was analyzed with a maximum power rating of 50 W and a current rate of 3.15 A. The main components of the system include solar cells, charged controllers, and a sun tracking system. The solar tracker is an automatic control system designed to track the solar modules in relation to the sun's direction. A linear drive actuator was used to track the modules with an energy consumption rate between 24 and 36 DC voltages. Power output solar cell equations were presented along with a review of batteries used for stationary and portable solar energy equipment. Issues related to cost of tracking systems were discussed. System sizing recommendations were provided, and solar cell design requirements were reviewed. A comparison of tracking and fixed solar energy systems was presented for a day in Yangon, Myanmar. It was concluded that solar tracking systems can be used to provide energy in rural and remote areas. 18 refs., 4 tabs., 5 figs.

  3. Light driven micro-robotics with holographic 3D tracking

    Science.gov (United States)

    Glückstad, Jesper

    2016-04-01

    We recently pioneered the concept of light-driven micro-robotics including the new and disruptive 3D-printed micro-tools coined Wave-guided Optical Waveguides that can be real-time optically trapped and "remote-controlled" in a volume with six-degrees-of-freedom. To be exploring the full potential of this new drone-like 3D light robotics approach in challenging microscopic geometries requires a versatile and real-time reconfigurable light coupling that can dynamically track a plurality of "light robots" in 3D to ensure continuous optimal light coupling on the fly. Our latest developments in this new and exciting area will be reviewed in this invited paper.

  4. Improved methods for chronic light-based motor mapping in mice: automated movement tracking with accelerometers, and chronic EEG recording in a bilateral thin-skull preparation.

    Directory of Open Access Journals (Sweden)

    Gergely eSilasi

    2013-07-01

    Full Text Available Optogenetic stimulation of the mouse cortex can be used to generate motor maps that are similar to maps derived from electrode-based stimulation. Here we present a refined set of procedures for repeated light-based motor mapping in ChR2-expressing mice implanted with a bilateral thinned-skull chronic window and a chronically implanted EEG electrode. Light stimulation is delivered sequentially to over 400 points across the cortex, and evoked movements are quantified on-line with a 3-axis accelerometer attached to each forelimb. Bilateral maps of forelimb movement amplitude and movement direction were generated at weekly intervals after recovery from cranial window implantation. We found that light pulses of ~2 mW produced well-defined maps that were centered approximately 0.7 mm anterior and 1.6 mm lateral from bregma. Map borders were defined by sites where light stimulation evoked EEG deflections, but not movements. Motor maps were similar in size and location between mice, and maps were stable over weeks in terms of the number of responsive sites, and the direction of evoked movements. We suggest that our method may be used to chronically assess evoked motor output in mice, and may be combined with other imaging tools to assess cortical reorganization or sensory-motor integration.

  5. Combining structured light and ladar for pose tracking in THz sensor management

    Science.gov (United States)

    Engström, Philip; Axelsson, Maria; Karlsson, Mikael

    2013-05-01

    Stand-off 3D THz imaging to detect concealed treats is currently under development. The technology can provide high resolution 3D range data of a passing subject showing layers of clothes and if there are concealed items. However, because it is a scanning sensor technology with a narrow field of view, the subjects pose and position need to be accurately tracked in real time to focus the system and map the imaged THz data to specific body parts. Structured light is a technique to obtain 3D range information. It is, for example, used in the Microsoft Kinect for pose tracking of game players in real time. We demonstrate how structured light can contribute to a THz sensor management system and track subjects in real time. The main advantage of structured light is its simplicity, the disadvantages are the sensitivity to lighting conditions and material properties as well as a relatively low accuracy. Time of flight laser scanning is a technique that complements structured light well, the accuracy is usually much higher and it is less sensitive to lighting conditions. We show that by combining the techniques it is possible to create a robust real time pose tracking system for THz sensor management. We present a concept system based on the Microsoft Kinect and a SICK LMS-511 laser scanner. The laser scanner is used for 2D tracking of the subjects, this tracking is then used to initialize and validate the Microsoft Kinect pose tracking. We have evaluated the sensors individually in both static and dynamic scenes and present their advantages and drawbacks.

  6. Design of Objects Tracking System Based on ARM Embedded Platform

    Institute of Scientific and Technical Information of China (English)

    XU Mei; SONG Yong-duan; LV Shao-dong; LIU Zhi-long; HUANG Cong-ying

    2014-01-01

    In recent years, according to the need of intelligent video surveillance system increasing rapidly in metropolitan cities ,a design based on S3C2440 microprocessor and embedded Linux operating system is adopted for real-time video target tracking. However, it is very challenging as embedded systems usually afford limited processing power and limited resources. Therefore, to address this problem, a real-time tracking algorithm using multi-features based on compressive sensing is proposed and implemented. The algorithm uses multiple matrix as the projection matrix of the compressive sensing and the compressed date as the multiple features to extract useful information needed by tracking process. Functions and libraries in OpenCV which were developed by Intel Corporation are utilized for building the tracking algorithms. It is tested with variant video sequences and the results show that the algorithm achieves stable tracking for the target moved of the light changed.

  7. External motion tracking for brain imaging: structured light tracking with invisible light

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte;

    2010-01-01

    The importance of motion correction in 3D medical imaging increases with increasing scanner resolution. It is necessary for scanners with long image acquisition and low contrast images to correct for patient motion in order to optimize image quality. We present a near infrared structured light st...

  8. 基于 AVRmegal16的二维太阳光自动跟踪系统设计%Design of two-dimensional solar light tracking system based on AVRmegal16

    Institute of Scientific and Technical Information of China (English)

    赵强松; 梁芬

    2015-01-01

    In order to take full advantages of the solar energy ,a two‐dimensional solar light automatic tracking system based on AVRmegal16 microcontroller is designed .This system consists of a signal acquisition module , a controller module ,and mechanical execution part .The experiment results show that it can adjust automatically and keep the photovoltaic panels and the sun incident angle vertical consistently .The system has advantages such as high tracking accuracy ,simple structure ,low power consumption ,and no tracking dead zone .%为了最大效率地利用太阳能,设计了基于AVRmegal16单片机的二维太阳光自动跟踪系统。该系统包括信号采集模块、控制器模块和机械执行部分。经测试,可以在不同天气状况下自动调整并使光伏电池板始终和太阳光入射角保持垂直。具有跟踪精度高、结构简单、能耗低等优点,且不存在追踪死区,具有较高的使用价值。

  9. 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...... that resembles the body surface of an infant, where the model is based on simple geometric shapes and a hierarchical skeleton model....

  10. Structured light 3D tracking system for measuring motions in PET brain imaging

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Jørgensen, Morten Rudkjær; Paulsen, Rasmus Reinhold

    2010-01-01

    with a DLP projector and a CCD camera is set up on a model of the High Resolution Research Tomograph (HRRT). Methods to reconstruct 3D point clouds of simple surfaces based on phase-shifting interferometry (PSI) are demonstrated. The projector and camera are calibrated using a simple stereo vision procedure......Patient motion during scanning deteriorates image quality, especially for high resolution PET scanners. A new proposal for a 3D head tracking system for motion correction in high resolution PET brain imaging is set up and demonstrated. A prototype tracking system based on structured light...

  11. SIFT based algorithm for point feature tracking

    Directory of Open Access Journals (Sweden)

    Adrian BURLACU

    2007-12-01

    Full Text Available In this paper a tracking algorithm for SIFT features in image sequences is developed. For each point feature extracted using SIFT algorithm a descriptor is computed using information from its neighborhood. Using an algorithm based on minimizing the distance between two descriptors tracking point features throughout image sequences is engaged. Experimental results, obtained from image sequences that capture scaling of different geometrical type object, reveal the performances of the tracking algorithm.

  12. Arduino based radioactive tracking system

    Science.gov (United States)

    Rahman, Nur Aira Abd; Rashid, Mohd Fazlie Bin Abdul; Rahman, Anwar Bin Abdul; Ramlan, Atikah

    2017-01-01

    There is a clear need to strengthen security measures to prevent any malevolent use or accidental misuse of radioactive sources. Some of these radioactive sources are regularly transported outside of office or laboratory premises for work and consultation purposes. This paper present the initial development of radioactive source tracking system, which combined Arduino microcontroller, Global Positioning System (GPS) and Global System for Mobile communication (GSM) technologies. The tracking system will help the owner to monitor the movement of the radioactive sources. Currently, the system is capable of tracking the movement of radioactive source through the GPS satellite signals. The GPS co-ordinate could either be transmitted to headquarters at fixed interval via Short Messaging Service (SMS) to enable real time monitoring, or stored in a memory card for offline monitoring and data logging.

  13. Multisensor Distributed Track Fusion AlgorithmBased on Strong Tracking Filter and Feedback Integration1)

    Institute of Scientific and Technical Information of China (English)

    YANGGuo-Sheng; WENCheng-Lin; TANMin

    2004-01-01

    A new multisensor distributed track fusion algorithm is put forward based on combiningthe feedback integration with the strong tracking Kalman filter. Firstly, an effective tracking gateis constructed by taking the intersection of the tracking gates formed before and after feedback.Secondly, on the basis of the constructed effective tracking gate, probabilistic data association andstrong tracking Kalman filter are combined to form the new multisensor distributed track fusionalgorithm. At last, simulation is performed on the original algorithm and the algorithm presented.

  14. High-precision heliostat for long-path light tracking

    Science.gov (United States)

    Hawat, Tom; Stephen, Thomas M.; DeMaziere, Martine M.; Neefs, Eddy

    2003-08-01

    A heliostat has been designed and built for use in optical remote sensing of the atmosphere. The heliostat uses two flat mirrors to track the sun and direct the sunlight to optical instruments. A stepper motor driven horizontal turntable is used to track the sun in azimuth and support an elevation assembly and a mechanical tower. The stepper motor driven elevation assembly drives an acquisition mirror that tracks the sun in elevation. This mirror directs the solar beam to a secondary mirror fixed on the mechanical tower. The secondary mirror then directs the solar beam along the axis of the tracker for use in measurements. A sensitive, high resolution CCD camera, receives a small part of the solar beam to analyze for fine servo-control. Ground based tests have demonstrated this instrument"s tracking capability for the sun, the moon, stars and for long pathlength sources. Presently, this system is coupled with a high-resolution Brucker 120M spectrometer used to obtain solar absorption spectra. The heliostat directs the solar radiation along the spectrometer optical axis. The pointing precision was measured to be better than 0.5 arcsec. A description of the heliostat is presented, as well as the results of ground tests.

  15. Central Tracking Detector Based on Scintillating Fibres

    CERN Multimedia

    2002-01-01

    Scintillating fibres form a reasonable compromise for central tracking detectors in terms of price, resolution, response time, occupancy and heat production. \\\\ \\\\ New fluorescents with large Stokes shifts have been produced, capable of working without wavelength shifters. Coherent multibundles have been developed to achieve high packing fractions. Small segments of tracker shell have been assembled and beam tests have confirmed expectations on spatial resolution. An opto-electronic delay line has been designed to delay the track patterns and enable coincidences with a first level trigger. Replacement of the conventional phosphor screen anode with a Si pixel chip is achieved. This tube is called ISPA-tube and has already been operated in beam tests with a scintillating fibres tracker. \\\\ \\\\ The aim of the proposal is to improve hit densities for small diameter fibres by increasing the fraction of trapped light, by reducing absorption and reflection losses, by reflecting light at the free fibre end, and by inc...

  16. Bayesian target tracking based on particle filter

    Institute of Scientific and Technical Information of China (English)

    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.

  17. Visual-tracking-based robot vision system

    Science.gov (United States)

    Deng, Keqiang; Wilson, Joseph N.; Ritter, Gerhard X.

    1992-11-01

    There are two kinds of depth perception for robot vision systems: quantitative and qualitative. The first one can be used to reconstruct the visible surfaces numerically while the second to describe the visible surfaces qualitatively. In this paper, we present a qualitative vision system suitable for intelligent robots. The goal of such a system is to perceive depth information qualitatively using monocular 2-D images. We first establish a set of propositions relating depth information, such as 3-D orientation and distance, to the changes of image region caused by camera motion. We then introduce an approximation-based visual tracking system. Given an object, the tracking system tracks its image while moving the camera in a way dependent upon the particular depth property to be perceived. Checking the data generated by the tracking system with our propositions provides us the depth information about the object. The visual tracking system can track image regions in real-time even as implemented on a PC AT clone machine, and mobile robots can naturally provide the inputs to our visual tracking system, therefore, we are able to construct a real-time, cost effective, monocular, qualitative and 3-dimensional robot vision system. To verify our idea, we present examples of perception of planar surface orientation, distance, size, dimensionality and convexity/concavity.

  18. Automated cell identification and tracking using nanoparticle moving-light-displays.

    Directory of Open Access Journals (Sweden)

    James A Tonkin

    Full Text Available An automated technique for the identification, tracking and analysis of biological cells is presented. It is based on the use of nanoparticles, enclosed within intra-cellular vesicles, to produce clusters of discrete, point-like fluorescent, light sources within the cells. Computational analysis of these light ensembles in successive time frames of a movie sequence, using k-means clustering and particle tracking algorithms, provides robust and automated discrimination of live cells and their motion and a quantitative measure of their proliferation. This approach is a cytometric version of the moving light display technique which is widely used for analyzing the biological motion of humans and animals. We use the endocytosis of CdTe/ZnS, core-shell quantum dots to produce the light displays within an A549, epithelial, lung cancer cell line, using time-lapse imaging with frame acquisition every 5 minutes over a 40 hour time period. The nanoparticle moving light displays provide simultaneous collection of cell motility data, resolution of mitotic traversal dynamics and identification of familial relationships allowing construction of multi-parameter lineage trees.

  19. Automated cell identification and tracking using nanoparticle moving-light-displays.

    Science.gov (United States)

    Tonkin, James A; Rees, Paul; Brown, Martyn R; Errington, Rachel J; Smith, Paul J; Chappell, Sally C; Summers, Huw D

    2012-01-01

    An automated technique for the identification, tracking and analysis of biological cells is presented. It is based on the use of nanoparticles, enclosed within intra-cellular vesicles, to produce clusters of discrete, point-like fluorescent, light sources within the cells. Computational analysis of these light ensembles in successive time frames of a movie sequence, using k-means clustering and particle tracking algorithms, provides robust and automated discrimination of live cells and their motion and a quantitative measure of their proliferation. This approach is a cytometric version of the moving light display technique which is widely used for analyzing the biological motion of humans and animals. We use the endocytosis of CdTe/ZnS, core-shell quantum dots to produce the light displays within an A549, epithelial, lung cancer cell line, using time-lapse imaging with frame acquisition every 5 minutes over a 40 hour time period. The nanoparticle moving light displays provide simultaneous collection of cell motility data, resolution of mitotic traversal dynamics and identification of familial relationships allowing construction of multi-parameter lineage trees.

  20. Triplet based online track finding in the PANDA-STT

    National Research Council Canada - National Science Library

    Mertens, Marius; Caldeira Balkeståhl, Li; Calén, Hans; Fransson, Kjell; Johansson, Tord; Kupsc, Andrzej; Marciniewski, Pawel; Schönning, Karin; Pettersson, Joachim; Wolke, Magnus; Zmeskal, Johann

    2014-01-01

    .... A variety of tracking algorithms is foreseen to process the different track topologies. The so-called Triplet Finder, which is presented here, is a track finding algorithm based on the central straw tube tracker (STT) of PANDA...

  1. Smith Predictor Based Robust Rapid Tracking Controller

    Institute of Scientific and Technical Information of China (English)

    LIU Hongbin; HU Dejin

    2006-01-01

    Precise model is hard to get in real application, a Smith predictor based robust rapid tracking controller for inaccurate model is proposed. Zero phase error feedforward controller which increases system closed-loop dynamics and disturbance observer based Smith feedback control which diminishes model hysteresis and improves stability are integrated. This method is applied in the noncircular machining with piezoelectric ceramic driver. The simulation and experiment show that the performance robustness and stability are well balanced in bandwidth about 200 Hz. The controller can decrease system hysteresis and get good tracking performance for predefined square-wave input signal.

  2. Dominant Correlogram Based Particle Filter Tracking

    Institute of Scientific and Technical Information of China (English)

    MAO Yan-fen; SHI Peng-fei

    2005-01-01

    A novel dominant correlogram based particle filter was proposed for an object tracking in visual surveillance. Particle filter outperforms the Kalman filter in non-linear and non-Gaussian estimation problem. This paper proposed incorporating spatial information into visual feature, and yields a reliable likelihood description of the observation and prediction. A similarity-ratio is defined to evaluate the effectivity of different similarity measurements in weighing samples. The experimental results demonstrate the effective and robust performance compared with the histogram based tracking in traffic scenes.

  3. Graph Model Based Indoor Tracking

    DEFF Research Database (Denmark)

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

    2009-01-01

    infrastructure for different symbolic positioning technologies, e.g., Bluetooth and RFID. More specifically, the paper proposes a model of indoor space that comprises a base graph and mappings that represent the topology of indoor space at different levels. The resulting model can be used for one or several...... indoor positioning technologies. Focusing on RFID-based positioning, an RFID specific reader deployment graph model is built from the base graph model. This model is then used in several algorithms for constructing and refining trajectories from raw RFID readings. Empirical studies with implementations...

  4. Adaptive DFT-based Interferometer Fringe Tracking

    Science.gov (United States)

    Wilson, Edward; Pedretti, Ettore; Bregman, Jesse; Mah, Robert W.; Traub, Wesley A.

    2004-01-01

    An automatic interferometer fringe tracking system has been developed, implemented, and tested at the Infrared Optical Telescope Array (IOTA) observatory at Mt. Hopkins, Arizona. The system can minimize the optical path differences (OPDs) for all three baselines of the Michelson stellar interferometer at IOTA. Based on sliding window discrete Fourier transform (DFT) calculations that were optimized for computational efficiency and robustness to atmospheric disturbances, the algorithm has also been tested extensively on off-line data. Implemented in ANSI C on the 266 MHz PowerPC processor running the VxWorks real-time operating system, the algorithm runs in approximately 2.0 milliseconds per scan (including all three interferograms), using the science camera and piezo scanners to measure and correct the OPDs. The adaptive DFT-based tracking algorithm should be applicable to other systems where there is a need to detect or track a signal with an approximately constant-frequency carrier pulse.

  5. Robust feature-based object tracking

    Science.gov (United States)

    Han, Bing; Roberts, William; Wu, Dapeng; Li, Jian

    2007-04-01

    Object tracking is an important component of many computer vision systems. It is widely used in video surveillance, robotics, 3D image reconstruction, medical imaging, and human computer interface. In this paper, we focus on unsupervised object tracking, i.e., without prior knowledge about the object to be tracked. To address this problem, we take a feature-based approach, i.e., using feature points (or landmark points) to represent objects. Feature-based object tracking consists of feature extraction and feature correspondence. Feature correspondence is particularly challenging since a feature point in one image may have many similar points in another image, resulting in ambiguity in feature correspondence. To resolve the ambiguity, algorithms, which use exhaustive search and correlation over a large neighborhood, have been proposed. However, these algorithms incur high computational complexity, which is not suitable for real-time tracking. In contrast, Tomasi and Kanade's tracking algorithm only searches corresponding points in a small candidate set, which significantly reduces computational complexity; but the algorithm may lose track of feature points in a long image sequence. To mitigate the limitations of the aforementioned algorithms, this paper proposes an efficient and robust feature-based tracking algorithm. The key idea of our algorithm is as below. For a given target feature point in one frame, we first find a corresponding point in the next frame, which minimizes the sum-of-squared-difference (SSD) between the two points; then we test whether the corresponding point gives large value under the so-called Harris criterion. If not, we further identify a candidate set of feature points in a small neighborhood of the target point; then find a corresponding point from the candidate set, which minimizes the SSD between the two points. The algorithm may output no corresponding point due to disappearance of the target point. Our algorithm is capable of tracking

  6. Solar concentrator with integrated tracking and light delivery system with summation

    Energy Technology Data Exchange (ETDEWEB)

    Maxey, Lonnie Curt

    2015-05-05

    A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector redirects the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and provides light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting that uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

  7. Solar concentrator with integrated tracking and light delivery system with collimation

    Energy Technology Data Exchange (ETDEWEB)

    Maxey, Lonnie Curt

    2015-06-09

    A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector directs the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and distributes light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting, uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

  8. Investigating the Mobility of Light Autonomous Tracked Vehicles using a High Performance Computing Simulation Capability

    Science.gov (United States)

    Negrut, Dan; Mazhar, Hammad; Melanz, Daniel; Lamb, David; Jayakumar, Paramsothy; Letherwood, Michael; Jain, Abhinandan; Quadrelli, Marco

    2012-01-01

    This paper is concerned with the physics-based simulation of light tracked vehicles operating on rough deformable terrain. The focus is on small autonomous vehicles, which weigh less than 100 lb and move on deformable and rough terrain that is feature rich and no longer representable using a continuum approach. A scenario of interest is, for instance, the simulation of a reconnaissance mission for a high mobility lightweight robot where objects such as a boulder or a ditch that could otherwise be considered small for a truck or tank, become major obstacles that can impede the mobility of the light autonomous vehicle and negatively impact the success of its mission. Analyzing and gauging the mobility and performance of these light vehicles is accomplished through a modeling and simulation capability called Chrono::Engine. Chrono::Engine relies on parallel execution on Graphics Processing Unit (GPU) cards.

  9. Nonlocal means filter-based speckle tracking.

    Science.gov (United States)

    Afsham, Narges; Rasoulian, Abtin; Najafi, Mohammad; Abolmaesumi, Purang; Rohling, Robert

    2015-08-01

    The objective of sensorless freehand 3-D ultrasound imaging is to eliminate the need for additional tracking hardware and reduce cost and complexity. However, the accuracy of current out-of-plane pose estimation is main obstacle for full 6-degree-of-freedom (DoF) tracking. We propose a new filter-based speckle tracking framework to increase the accuracy of out-of-plane displacement estimation. In this framework, we use the displacement estimation not only for the specific speckle pattern, but for the entire image. We develop a nonlocal means (NLM) filter based on a probabilistic normal variance mixture model of ultrasound, known as Rician-inverse Gaussian (RiIG). To aggregate the local displacement estimations, Stein's unbiased risk estimate (SURE) is used as a quality measure of the estimations. We derive an explicit analytical form of SURE for the RiIG model and use it as a weight factor. The proposed filter-based speckle tracking framework is formulated and evaluated for three commonly used noise models, including the RiIG model. The out-of-plane estimations are compared with our previously proposed model-based algorithm in a set of ex vivo experiments for different tissue types. We show that the proposed RiIG filter-based method is more accurate and less tissue-dependent than the other methods. The proposed method is also evaluated in vivo on the spines of five different subjects to assess the feasibility of a clinical application. The 6-DoF transform parameters are estimated and compared with the electromagnetic tracker measurements. The results show higher tracking accuracy for typical small lateral displacements and tilt rotations between image pairs.

  10. Year-round tracking of small trans-Saharan migrants using light-level geolocators.

    Science.gov (United States)

    Bächler, Erich; Hahn, Steffen; Schaub, Michael; Arlettaz, Raphaël; Jenni, Lukas; Fox, James W; Afanasyev, Vsevolod; Liechti, Felix

    2010-03-05

    Since 1899 ringing (or banding) remained the most important source of information about migration routes, stopover sites and wintering grounds for birds that are too small to carry satellite-based tracking systems. Despite the large quantity of migrating birds ringed in their breeding areas in Europe, the number of ring recoveries from sub-Saharan Africa is very low and therefore the whereabouts of most small bird species outside the breeding season remain a mystery. With new miniaturized light-level geolocators it is now possible to look beyond the limits of ring recovery data. Here we show for the first time year round tracks of a near passerine trans-Saharan migrant, the European Hoopoe (Upupa epops epops). Three birds wintered in the Sahel zone of Western Africa where they remained stationary for most of the time. One bird chose a south-easterly route following the Italian peninsula. Birds from the same breeding population used different migration routes and wintering sites, suggesting a low level of migratory connectivity between breeding and wintering areas. Our tracking of a near passerine bird, the European Hoopoe, with light-level geolocators opens a new chapter in the research of Palaearctic-African bird migration as this new tool revolutionizes our ability to discover migration routes, stopover sites and wintering grounds of small birds.

  11. Year-round tracking of small trans-Saharan migrants using light-level geolocators.

    Directory of Open Access Journals (Sweden)

    Erich Bächler

    Full Text Available Since 1899 ringing (or banding remained the most important source of information about migration routes, stopover sites and wintering grounds for birds that are too small to carry satellite-based tracking systems. Despite the large quantity of migrating birds ringed in their breeding areas in Europe, the number of ring recoveries from sub-Saharan Africa is very low and therefore the whereabouts of most small bird species outside the breeding season remain a mystery. With new miniaturized light-level geolocators it is now possible to look beyond the limits of ring recovery data. Here we show for the first time year round tracks of a near passerine trans-Saharan migrant, the European Hoopoe (Upupa epops epops. Three birds wintered in the Sahel zone of Western Africa where they remained stationary for most of the time. One bird chose a south-easterly route following the Italian peninsula. Birds from the same breeding population used different migration routes and wintering sites, suggesting a low level of migratory connectivity between breeding and wintering areas. Our tracking of a near passerine bird, the European Hoopoe, with light-level geolocators opens a new chapter in the research of Palaearctic-African bird migration as this new tool revolutionizes our ability to discover migration routes, stopover sites and wintering grounds of small birds.

  12. Simple quality assurance method of dynamic tumor tracking with the gimbaled linac system using a light field.

    Science.gov (United States)

    Miura, Hideharu; Ozawa, Shuichi; Hayata, Masahiro; Tsuda, Shintaro; Yamada, Kiyoshi; Nagata, Yasushi

    2016-09-08

    We proposed a simple visual method for evaluating the dynamic tumor tracking (DTT) accuracy of a gimbal mechanism using a light field. A single photon beam was set with a field size of 30 × 30 mm2 at a gantry angle of 90°. The center of a cube phantom was set up at the isocenter of a motion table, and 4D modeling was performed based on the tumor and infrared (IR) marker motion. After 4D modeling, the cube phantom was replaced with a sheet of paper, which was placed perpen-dicularly, and a light field was projected on the sheet of paper. The light field was recorded using a web camera in a treatment room that was as dark as possible. Calculated images from each image obtained using the camera were summed to compose a total summation image. Sinusoidal motion sequences were produced by moving the phantom with a fixed amplitude of 20 mm and different breathing periods of 2, 4, 6, and 8 s. The light field was projected on the sheet of paper under three conditions: with the moving phantom and DTT based on the motion of the phantom, with the moving phantom and non-DTT, and with a stationary phantom for comparison. The values of tracking errors using the light field were 1.12 ± 0.72, 0.31 ± 0.19, 0.27 ± 0.12, and 0.15 ± 0.09 mm for breathing periods of 2, 4, 6, and 8s, respectively. The tracking accuracy showed dependence on the breath-ing period. We proposed a simple quality assurance (QA) process for the tracking accuracy of a gimbal mechanism system using a light field and web camera. Our method can assess the tracking accuracy using a light field without irradiation and clearly visualize distributions like film dosimetry.

  13. Ion track reconstruction in 3D using alumina-based fluorescent nuclear track detectors

    CERN Document Server

    Niklas, Martin; Akselrod, Mark S; Abollahi, Amir; Jäkel, Oliver; Greilich, Steffen

    2013-01-01

    Fluorescent nuclear track detectors (FNTDs) based on Al2O3:C,Mg single crystal combined with confocal microscopy provide 3D information on ion tracks with a resolution only limited by light diffraction. FNTDs are also ideal substrates to be coated with cells to engineer cell-fluorescent ion track hybrid detectors. This radiobiological tool enables a novel platform linking cell responses to physical dose deposition on a sub-cellular level in proton and heavy ion therapies. To achieve spatial correlation between single ion hits in the cell coating and its biological response the ion traversals have to be reconstructed in 3D using the depth information gained by the FNTD read-out. FNTDs were coated with a confluent human lung adenocarcinoma epithelial cell layer. Carbon ion irradiation of the hybrid detector was performed perpendicular and angular to the detector surface. In-situ imaging of the fluorescently labeled cell layer and the FNTD was performed in a sequential read-out. Making use of the trajectory info...

  14. Kernel based visual tracking with scale invariant features

    Institute of Scientific and Technical Information of China (English)

    Risheng Han; Zhongliang Jing; Yuanxiang Li

    2008-01-01

    The kernel based tracking has two disadvantages:the tracking window size cannot be adjusted efficiently,and the kernel based color distribution may not have enough ability to discriminate object from clutter background.FDr boosting up the feature's discriminating ability,both scale invariant features and kernel based color distribution features are used as descriptors of tracked object.The proposed algorithm can keep tracking object of varying scales even when the surrounding background is similar to the object's appearance.

  15. Research on target tracking in coal mine based on optical flow method

    Science.gov (United States)

    Xue, Hongye; Xiao, Qingwei

    2015-03-01

    To recognize, track and count the bolting machine in coal mine video images, a real-time target tracking method based on the Lucas-Kanade sparse optical flow is proposed in this paper. In the method, we judge whether the moving target deviate from its trajectory, predicate and correct the position of the moving target. The method solves the problem of failure to track the target or lose the target because of the weak light, uneven illumination and blocking. Using the VC++ platform and Opencv lib we complete the recognition and tracking. The validity of the method is verified by the result of the experiment.

  16. Hybrid Copper-Silver Conductive Tracks for Enhanced Oxidation Resistance under Flash Light Sintering.

    Science.gov (United States)

    Yim, Changyong; Sandwell, Allen; Park, Simon S

    2016-08-31

    We developed a simple method to prepare hybrid copper-silver conductive tracks under flash light sintering. The developed metal nanoparticle-based ink is convenient because its preparation process is free of any tedious washing steps. The inks were composed of commercially available copper nanoparticles which were mixed with formic acid, silver nitrate, and diethylene glycol. The role of formic acid is to remove the native copper oxide layer on the surface of the copper nanoparticles. In this way, it facilitates the formation of a silver outer shell on the surface of the copper nanoparticles through a galvanic replacement. In the presence of formic acid, the copper nanoparticles formed copper formate, which was present in the unsintered tracks. However, under illumination by a xenon flash light, the copper formate was then converted to copper. Moreover, the resistance of the copper-only films increased by 6 orders of magnitude when oxidized at high temperatures (∼220 °C). However, addition of silver nitrate to the inks suppressed the oxidation of the hybrid copper-silver films, and the resistance changes in these inks at high temperatures were greatly reduced. In addition, the hybrid inks proved to be advantageous for use in electrical circuits as they demonstrated a stable electrical conductivity after exposure to ambient air at 180 °C.

  17. Neural mass model-based tracking of anesthetic brain states

    NARCIS (Netherlands)

    Kuhlmann, Levin; Freestone, Dean R.; Manton, Jonathan H.; Heyse, Bjorn; Vereecke, Hugo E. M.; Lipping, Tarmo; Struys, Michel M. R. F.; Liley, David T. J.

    2016-01-01

    Neural mass model-based tracking of brain states from electroencephalographic signals holds the promise of simultaneously tracking brain states while inferring underlying physiological changes in various neuroscientific and clinical applications. Here, neural mass model-based tracking of brain state

  18. 融合最大功率点追踪和寻光感知技术的太阳能智能跟踪系统设计%Design of an Intelligent Solar Energy Tracking System Based on Maximum Power Point Tracking With Light Search Perceptive Technology

    Institute of Scientific and Technical Information of China (English)

    施云波; 葛春志; 王萌萌; 汪亚东; 渠立亮

    2014-01-01

    In allusion to such defects of current photovoltaic (PV) cell generation system adopting solar energy tracking technology as larger tracking error, weak anti-interference performance and higher system energy consumption, through integration of maximum power point tracking (MPPT) with intelligent light search perceptive technology an intelligent solar energy tracking system for PV cells is designed to implement the maximization of photon to current conversion efficiency. Utilizing the principle of projection a light search sensor is developed and adding light intensity sensing unit to the sensor an intelligent light search sensing module is formed to eliminate the affect of climatic conditions to implement the all-weather operation of the designed tracking system. To reduce the power consumption of the designed system, the tracking mode is designed as the discrete one, that is, after the necessary detection and control of such peripheral equipments as electric motor and its driving module, the light search sensing module and so on while the fixed clock signal arrives the designed system is in the standby status when the designed system is idle. The perturbation and observation method to implement the MPPT is improved and optimized, and a differentiation perturbation mode is proposed to avoid the oscillation near the maximum power point and malfunction during light intensity variation due to traditional perturbation and observation method. Experimental verification results show that the tracking resolution of the designed tracking system can achieve to 0.344°, the system error is less than 2.5° and the charging efficiency of the PV cells can be increased by more than 40%.%针对目前跟踪式太阳能光伏电池发电系统跟踪误差较大、抗干扰性较差、系统耗能较高等问题,融合最大功率点追踪(maximum power point tracking,MPPT)和智能寻光感知技术设计了一套太阳能光伏电池跟踪系统,实现了光电转化效率

  19. Long-term visual tracking based on correlation filters

    Science.gov (United States)

    Wei, Quanlu; Lao, Songyang; Bai, Liang

    2017-03-01

    In order to accomplish the long term visual tracking task in complex scenes, solve problems of scale variation, appearance variation and tracking failure, a long term tracking algorithm is given based on the framework of collaborative correlation tracking. Firstly, we integrate several powerful features to boost the represent ability based on the kernel correlation filter, and extend the filter by embedding a scale factor into the kernelized matrix to handle the scale variation. Then, we use the Peak-Sidelobe Ratio to decide whether the object is tracked successfully, and a CUR filter for re-detection the object in case of tracking failure is learnt with random sampling. Corresponding experiment is performed on 17 challenging benchmark video sequences. Compared with the 8 existing state-of-the-art algorithms based on discriminative learning method, the results show that the proposed algorithm improves the tracking performance on several indexes, and is robust to complex scenes for long term visual tracking.

  20. Empirical Study on Designing of Gaze Tracking Camera Based on the Information of User's Head Movement.

    Science.gov (United States)

    Pan, Weiyuan; Jung, Dongwook; Yoon, Hyo Sik; Lee, Dong Eun; Naqvi, Rizwan Ali; Lee, Kwan Woo; Park, Kang Ryoung

    2016-08-31

    Gaze tracking is the technology that identifies a region in space that a user is looking at. Most previous non-wearable gaze tracking systems use a near-infrared (NIR) light camera with an NIR illuminator. Based on the kind of camera lens used, the viewing angle and depth-of-field (DOF) of a gaze tracking camera can be different, which affects the performance of the gaze tracking system. Nevertheless, to our best knowledge, most previous researches implemented gaze tracking cameras without ground truth information for determining the optimal viewing angle and DOF of the camera lens. Eye-tracker manufacturers might also use ground truth information, but they do not provide this in public. Therefore, researchers and developers of gaze tracking systems cannot refer to such information for implementing gaze tracking system. We address this problem providing an empirical study in which we design an optimal gaze tracking camera based on experimental measurements of the amount and velocity of user's head movements. Based on our results and analyses, researchers and developers might be able to more easily implement an optimal gaze tracking system. Experimental results show that our gaze tracking system shows high performance in terms of accuracy, user convenience and interest.

  1. Detection of scintillation light in coincidence with ionizing tracks in a liquid argon time projection chamber

    CERN Document Server

    Cennini, P; Rubbia, Carlo; Sergiampietri, F; Bueno, A G; Campanelli, M; Goudsmit, P; Rubbia, André; Periale, L; Suzuki, S; Chen, C; Chen, Y; He, K; Huang, X; Li, Z; Lu, F; Ma, J; Xu, G; Xu, Z; Zhang, C; Zhang, Q; Zheng, S; Cavanna, F; Mazza, D; Piano Mortari, G; Petrera, S; Rossi, C; Mannocchi, G; Picchi, P; Arneodo, F; De Mitri, I; Palamara, O; Cavalli, D; Ferrari, A; Sala, P R; Borio di Tigliole, A A; Cesana, A; Terrani, M; Zavattari, C; Baibusinov, S; Bettini, A; Carpanese, C; Centro, Sandro; Favaretto, D; Pascoli, D; Pepato, Adriano; Pietropaolo, F; Ventura, Sandro; Benetti, P; Calligarich, E; Campo, S; Coco, S; Dolfini, R; Ghedi, B; Gigli-Berzolari, A; Mauri, F; Mazzone, L; Montanari, C; Piazzoli, A; Rappoldi, A; Raselli, G L; Rebuzzi, D; Rossella, M; Scannicchio, D A; Torre, P; Vignoli, C; Cline, D; Otwinowski, S; Wang, H; Woo, J

    1999-01-01

    A system to detect light from liquid argon scintillation has been implemented in a small, ICARUS-like, liquid argon time projection chamber. The system, which uses a VUV-sensitive photomultiplier to collect the light, has recorded many ionizing tracks from cosmic-rays in coincidence with scintillation signals. Our measurements demonstrate that scintillation light detection can provide an effective method for absolute time measurement of events and eventually a useful trigger signal. (19 refs).

  2. Light-driven micro-robotics with holographic 3D tracking

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    2016-01-01

    We recently pioneered the concept of ligh-driven micro-robotics including the new and disruptive 3D-printed micro-tools coined Wave-guided Optical Waveguides that can be real-time optically trapped and “remote-controlled” in a volume with six-degrees-of-freedom. To be exploring the full potential...... of this new drone-like 3D light robotics approach in challenging microscopic geometries requires a versatile and real-time reconfigurable light coupling that can dynamically track a plurality of “light robots” in 3D to ensure continuous optimal light coupling on the fly. Our latest developments in this new...

  3. Design and performance comparison of fuzzy logic based tracking controllers

    Science.gov (United States)

    Lea, Robert N.; Jani, Yashvant

    1992-01-01

    Several camera tracking controllers based on fuzzy logic principles have been designed and tested in software simulation in the software technology branch at the Johnson Space Center. The fuzzy logic based controllers utilize range measurement and pixel positions from the image as input parameters and provide pan and tilt gimble rate commands as output. Two designs of the rulebase and tuning process applied to the membership functions are discussed in light of optimizing performance. Seven test cases have been designed to test the performance of the controllers for proximity operations where approaches like v-bar, fly-around and station keeping are performed. The controllers are compared in terms of responsiveness, and ability to maintain the object in the field-of-view of the camera. Advantages of the fuzzy logic approach with respect to the conventional approach have been discussed in terms of simplicity and robustness.

  4. Method for precise charge measurements of relativistic light nuclei, Z<=3, in nuclear track emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Bloomer, M.A.; Heckman, H.H.; Karant, Y.J. (California Univ., Berkeley (USA). Div. of Nuclear Science)

    1983-09-15

    A technique for precise charge measurement of particle tracks in nuclear emulsion is described. The method is based on measurements of the lacunarity, i.e., fractional transparency, and/or the fractional opacity in the linear track structure of ionization tracks observed in the developed emulsion. The method yields estimates of charge for relativistic Z=1 and 2 nuclei to a precision of proportional +- 0.05 charge units, in agreement with Barkas' theoretical model of track structure. The technique is applicable up to Zapprox.=6, but with diminished charge resolution with increasing charge above Z=3. Systematics that affect the accuracy of the method are noted and discussed.

  5. Beacon system based on light-emitting diode sources for runways lighting

    Science.gov (United States)

    Montes, Mario González; Vázquez, Daniel; Fernandez-Balbuena, Antonio A.; Bernabeu, Eusebio

    2014-06-01

    New aeronautical ground lighting techniques are becoming increasingly important to ensure the safety and reduce the maintenance costs of the plane's tracks. Until recently, tracks had embedded lighting systems whose sources were based on incandescent lamps. But incandescent lamps have several disadvantages: high energy consumption and frequent breakdowns that result in high maintenance costs (lamp average life-time is ˜1500 operating hours) and the lamp's technology has a lack of new lighting functions, such as signal handling and modification. To solve these problems, the industry has developed systems based on light-emitting diode (LED) technology with improved features: (1) LED lighting consumes one tenth the power, (2) it improves preventive maintenance (an LED's lifetime range is between 25,000 and 100,000 hours), and (3) LED lighting technology can be controlled remotely according to the needs of the track configuration. LEDs have been in use for more than three decades, but only recently, around 2002, have they begun to be used as visual aids, representing the greatest potential change for airport lighting since their inception in the 1920s. Currently, embedded LED systems are not being broadly used due to the specific constraints of the rules and regulations of airports (beacon dimensions, power system technology, etc.). The fundamental requirements applied to embedded lighting systems are to be hosted on a volume where the dimensions are usually critical and also to integrate all the essential components for operation. An embedded architecture that meets the lighting regulations for airport runways is presented. The present work is divided into three main tasks: development of an optical system to optimize lighting according to International Civil Aviation Organization, manufacturing prototype, and model validation.

  6. Target tracking based on frequency spectrum amplitude

    Institute of Scientific and Technical Information of China (English)

    Guo Huidong; Zhang Xinhua; Xia Zhijun

    2006-01-01

    The amplitude of frequency spectrum can be integrated with probabilistic data association (PDA) to distinguish the target with clutter echoes, especially in low SNR underwater environment. A new target-tracking algorithm is presented which adopts the amplitude of frequency spectrum to improve target tracking in clutter. The probabilistic density distribution of frequency spectrum amplitude is analyzed. By simulation, the results show that the algorithm is superior to PDA. This approach enhances stability for the association probability and increases the performance of target tracking.

  7. TrackEtching - A Java based code for etched track profile calculations in SSNTDs

    Science.gov (United States)

    Muraleedhara Varier, K.; Sankar, V.; Gangadathan, M. P.

    2017-09-01

    A java code incorporating a user friendly GUI has been developed to calculate the parameters of chemically etched track profiles of ion-irradiated solid state nuclear track detectors. Huygen's construction of wavefronts based on secondary wavelets has been used to numerically calculate the etched track profile as a function of the etching time. Provision for normal incidence and oblique incidence on the detector surface has been incorporated. Results in typical cases are presented and compared with experimental data. Different expressions for the variation of track etch rate as a function of the ion energy have been utilized. The best set of values of the parameters in the expressions can be obtained by comparing with available experimental data. Critical angle for track development can also be calculated using the present code.

  8. Maximum Power Point Tracking of Photovoltaic System for Traffic Light Application

    Directory of Open Access Journals (Sweden)

    Riza Muhida

    2013-07-01

    Full Text Available Photovoltaic traffic light system is a significant application of renewable energy source. The development of the system is an alternative effort of local authority to reduce expenditure for paying fees to power supplier which the power comes from conventional energy source. Since photovoltaic (PV modules still have relatively low conversion efficiency, an alternative control of maximum power point tracking (MPPT method is applied to the traffic light system. MPPT is intended to catch up the maximum power at daytime in order to charge the battery at the maximum rate in which the power from the battery is intended to be used at night time or cloudy day. MPPT is actually a DC-DC converter that can step up or down voltage in order to achieve the maximum power using Pulse Width Modulation (PWM control. From experiment, we obtained the voltage of operation using MPPT is at 16.454 V, this value has error of 2.6%, if we compared with maximum power point voltage of PV module that is 16.9 V. Based on this result it can be said that this MPPT control works successfully to deliver the power from PV module to battery maximally.

  9. The FPGA based L1 track finding Tracklet approach

    Science.gov (United States)

    Kyriacou, Savvas; CMS Collaboration

    2017-01-01

    The High Luminosity upgraded LHC is expected to deliver proton-proton collisions per 25ns with an estimated 140-200 pile up interactions per bunch crossing. Ultrafast track finding is vital for handling trigger rates in such conditions. An FPGA based road search algorithm is developed, the Tracklet approach one of a few currently under consideration, for the CMS L1 trigger system. Based on low/high transverse momentum track discrimination and designed for the HL upgraded outer tracker, the algorithm achieves microsecond scale track reconstruction in the expected high track multiplicity environment. The Tracklet method overview, implementation, hardware demonstrator and performance results are presented and discussed.

  10. Building occupant and asset localization and tracking using visible light communication

    Science.gov (United States)

    Nyarko, Kofi; Emiyah, Christian; Mbugua, Samuel

    2016-05-01

    This research demonstrates how inexpensive commercial off-the-shelf lighting components and microcontrollers can be used to construct a solution for occupant and asset localization and tracking through visible light communication (VLC). Through the modulation of the emitted light from networked LED luminaires, the location of a receiver can be determined. This paper describes the implementation of the VLC enabled LED luminaires, in addition to the infrared synchronization protocol, which enabled inexpensive white LEDs to be time division multiplexed to avoid packet collisions. Luminaires use token message passing to regulate packet transmission. Physical construction of these luminaires is discussed in addition to the simulated performance of this system.

  11. Visual tracking method based on cuckoo search algorithm

    Science.gov (United States)

    Gao, Ming-Liang; Yin, Li-Ju; Zou, Guo-Feng; Li, Hai-Tao; Liu, Wei

    2015-07-01

    Cuckoo search (CS) is a new meta-heuristic optimization algorithm that is based on the obligate brood parasitic behavior of some cuckoo species in combination with the Lévy flight behavior of some birds and fruit flies. It has been found to be efficient in solving global optimization problems. An application of CS is presented to solve the visual tracking problem. The relationship between optimization and visual tracking is comparatively studied and the parameters' sensitivity and adjustment of CS in the tracking system are experimentally studied. To demonstrate the tracking ability of a CS-based tracker, a comparative study of tracking accuracy and speed of the CS-based tracker with six "state-of-art" trackers, namely, particle filter, meanshift, PSO, ensemble tracker, fragments tracker, and compressive tracker are presented. Comparative results show that the CS-based tracker outperforms the other trackers.

  12. Object Tracking based on Fuzzy Color Blobs

    Directory of Open Access Journals (Sweden)

    Francisco-Javier Montecillo-Puente

    2012-03-01

    Full Text Available One of the mayor goals in computer vision is object representation. Object representation aims to determine a set of features that best represents a specific object in an image, for example interest points, edges, color and texture. However, objects are generally composed of several regions containing different information which is more or less convenient to be represented by one of these features. Furthermore, each of these regions could be static or moving with respect to each other. In this sense, this paper presents an object representation based on fuzzy color blobs and spatial relationships among them. This approach of object representation is used to track rigid and articulated objects.En visión por computadora una de las metas principales es la representación de objetos. Dada una imagen, la representación de objetos intenta definir un conjunto de características que mejor los representa a partir de la información visual. Por ejemplo, se han utilizado puntos de interés, bordes, color y textura. Sin embargo, los objetos están formados por diferentes regiones con información variada que es más o menos conveniente a ser representada por alguna de las características antes mencionadas. Además, cada una de estas regiones puede estar estática o en movimiento respecto al resto de las regiones que componen el objeto. En este sentido, este trabajo presenta una representación de objetos basadas en regiones de color difuso y sus relaciones espaciales. Este enfoque es utilizado para el seguimiento de objetos rígidos y articulados.

  13. Stereo-Based Tracking-by-Multiple Hypotheses Framework for Multiple Vehicle Detection and Tracking

    Directory of Open Access Journals (Sweden)

    Young-Chul Lim

    2013-07-01

    Full Text Available In this paper, we present a tracking‐by‐multiple hypotheses framework to detect and track multiple vehicles accurately and precisely. The tracking‐by‐ multiple hypotheses framework consists of obstacle detection, vehicle recognition, visual tracking, global position tracking, data association and particle filtering. The multiple hypotheses are from obstacle detection, vehicle recognition and visual tracking. The obstacle detection detects all the obstacles on the road. The vehicle recognition classifies the detected obstacles as vehicles or non-vehicles. 3D feature‐based visual tracking estimates the current target state using the previous target state. The multiple hypotheses should be linked to corresponding tracks to update the target state. The hierarchical data association method assigns multiple tracks to the correct hypotheses with multiple similarity functions. In the particle filter framework, the target state is updated using the Gaussian motion model and the observation model with associated multiple hypotheses. The experimental results demonstrate that the proposed method enhances the accuracy and precision of the region of interest.

  14. Cluster-based distributed face tracking in camera networks.

    Science.gov (United States)

    Yoder, Josiah; Medeiros, Henry; Park, Johnny; Kak, Avinash C

    2010-10-01

    In this paper, we present a distributed multicamera face tracking system suitable for large wired camera networks. Unlike previous multicamera face tracking systems, our system does not require a central server to coordinate the entire tracking effort. Instead, an efficient camera clustering protocol is used to dynamically form groups of cameras for in-network tracking of individual faces. The clustering protocol includes cluster propagation mechanisms that allow the computational load of face tracking to be transferred to different cameras as the target objects move. Furthermore, the dynamic election of cluster leaders provides robustness against system failures. Our experimental results show that our cluster-based distributed face tracker is capable of accurately tracking multiple faces in real-time. The overall performance of the distributed system is comparable to that of a centralized face tracker, while presenting the advantages of scalability and robustness.

  15. Holidays in lights: Tracking cultural patterns in demand for energy services

    Science.gov (United States)

    Román, Miguel O.; Stokes, Eleanor C.

    2015-06-01

    Successful climate change mitigation will involve not only technological innovation, but also innovation in how we understand the societal and individual behaviors that shape the demand for energy services. Traditionally, individual energy behaviors have been described as a function of utility optimization and behavioral economics, with price restructuring as the dominant policy lever. Previous research at the macro-level has identified economic activity, power generation and technology, and economic role as significant factors that shape energy use. However, most demand models lack basic contextual information on how dominant social phenomenon, the changing demographics of cities, and the sociocultural setting within which people operate, affect energy decisions and use patterns. Here we use high-quality Suomi-NPP VIIRS nighttime environmental products to: (1) observe aggregate human behavior through variations in energy service demand patterns during the Christmas and New Year's season and the Holy Month of Ramadan and (2) demonstrate that patterns in energy behaviors closely track sociocultural boundaries at the country, city, and district level. These findings indicate that energy decision making and demand is a sociocultural process as well as an economic process, often involving a combination of individual price-based incentives and societal-level factors. While nighttime satellite imagery has been used to map regional energy infrastructure distribution, tracking daily dynamic lighting demand at three major scales of urbanization is novel. This methodology can enrich research on the relative importance of drivers of energy demand and conservation behaviors at fine scales. Our initial results demonstrate the importance of seating energy demand frameworks in a social context.

  16. Taylor Series-based Tracking Algorithm for Through-Wall Tracking of a Moving Person

    Directory of Open Access Journals (Sweden)

    Mária Švecová

    2010-04-01

    Full Text Available Target tracking using time of arrival measurements belongs to the primary taskssolved within radar signal processing. In this paper, the Taylor series-based trackingalgorithm that uses time of arrival measurements for through wall tracking of the movingtarget is introduced. The proposed algorithm is derived from the Taylor series methodapplied for target localization. In contrast to the Taylor series method, the Taylor seriesbasedtracking algorithm exploits for target positioning not only actual time of arrivalmeasurements, but also the target position estimated in the previous time instant. In orderto improve the tracking ability of the proposed algorithm, a suitable weighting of the inputdata of the algorithm is applied. The performance of the Taylor series-based trackingalgorithm will be compared with the performance of the direct calculation method andlinear Kalman filtering. For that purpose, two real scenarios of through wall tracking of amoving person will be analysed. The obtained results will show very clearly that the newTaylor series based tracking algorithm introduced in this paper can provide the betterestimate of the target trajectory than the other tested localization and tracking algorithms.

  17. Microcontroller Based Solar tracking System for enhancing efficiency of a Photovoltaic system

    Directory of Open Access Journals (Sweden)

    Shaifali Jain,

    2014-09-01

    Full Text Available In today‟s scenario of increasing energy needs, there is a huge dependence on renewable energy sources along with the conventional sources. One of the most important renewable energy resources is the sun. However, the problem with solar power is that it is directly dependent on light intensity. To produce the maximum amount of energy, a solar panel must be perpendicular to the light source. Because the sun moves both throughout the day as well as throughout a year, a solar panel must be able to follow the sun‟s movement to produce the maximum possible power. There are a large number of methods available for solar tracking and hence maximizing the output .This paper proposes an Arduino Uno microcontroller board based solar tracking system. As compared to the conventional solar panels, the one mounted with microcontroller based tracking system will give enhanced output.

  18. RKP based secure tracking in wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To enhancing the wireless sensor network's security in target tracking and locating application,this article proposes a tracking cluster based mobile cluster distributed group rekeying protocol (MCDGR).Based on the given sensitivity,sensors can locate the moving object in the monitored area and form a tracking cluster around it.This tracking cluster can follow the target logically,process data on the target and report to the sink node,and thus achieve the tracking function.We introduce a multi-path reinforcement scheme,q-composition scheme and one-way cryptographic hash function based random key predietribution algorithm (RKP),which can guarantee a high accuracy and security and a low energy consumption on the same time in large-scale sensor networks.

  19. Automatic face detection and tracking based on Adaboost with camshift algorithm

    Science.gov (United States)

    Lin, Hui; Long, JianFeng

    2011-10-01

    With the development of information technology, video surveillance is widely used in security monitoring and identity recognition. For most of pure face tracking algorithms are hard to specify the initial location and scale of face automatically, this paper proposes a fast and robust method to detect and track face by combining adaboost with camshift algorithm. At first, the location and scale of face is specified by adaboost algorithm based on Haar-like features and it will be conveyed to the initial search window automatically. Then, we apply camshift algorithm to track face. The experimental results based on OpenCV software yield good results, even in some special circumstances, such as light changing and face rapid movement. Besides, by drawing out the tracking trajectory of face movement, some abnormal behavior events can be analyzed.

  20. Roadmap to tracking based business and intelligent products

    NARCIS (Netherlands)

    Holmström, J.; Kajosaari, R.; Främling, K.; Langius, E.A.F.

    2009-01-01

    Item-centric tracking is an opportunity to increase visibility and control in different operations of a company. The economical feasibility of item-centric tracking is based on recent technological developments for monitoring the material flow on the item-level instead of the material type-level. It

  1. Homography-based grasp tracking for planar objects

    NARCIS (Netherlands)

    Carloni, Raffaella; Recatala, Gabriel; Melchiorri, Claudio; Sanz, Pedro J.; Cervera, Enric

    The visual tracking of grasp points is an essential operation for the execution of an approaching movement of a robot arm to an object: the grasp points are used as features for the definition of the control law. This work describes a strategy for tracking grasps on planar objects based on the use

  2. GPS Based Tracking of Mobile Objects

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Torp, Kristian

    2006-01-01

    Denne artikel beskriver hvorledes man med eksisterende teknologi, herunder Global Position System og General Packet Radio Service, effektivt kan tracke mobile objekter som f.eks. køretøjer med en garanteret nøjagtighed. Først beskrives den teknologiske platform. Herefter beskrives tre forskellige...

  3. GPS Based Tracking of Mobile Objects

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Torp, Kristian

    2006-01-01

    Denne artikel beskriver hvorledes man med eksisterende teknologi, herunder Global Position System og General Packet Radio Service, effektivt kan tracke mobile objekter som f.eks. køretøjer med en garanteret nøjagtighed. Først beskrives den teknologiske platform. Herefter beskrives tre forskellige...

  4. Analysis of light guiding property in light piped based solar concentrator

    Science.gov (United States)

    Whang, Allen J.; Chuang, Chun-Hsien, Jr.; Chen, Yi-Yung

    2008-02-01

    Recently, many researchers have tried to design a system for indoor illumination because the benefits of solar systems. A simple parabolic reflector is often used to collect sunlight but the efficiency is poor when sunlight isn't incident normally. Therefore, an accurate machine to track sun has to be used. In order to get better tolerance, a light pipe based solar concentrator (LPBSC) which comprises a parabolic reflector and a hollow reflective light pipe is proposed. We develop a math model which combines the reflection times of sunlight in light pipe and the candela data of parabolic reflector to analyze the efficiency. And then, straight light pipe is replaced by tapered light pipe to improve the tolerance. Optical simulation software, TracePro, and mathematical software, MATLAB, are used to prove the model is correct and feasible. In the results, LPBSC can improve the tolerance to get good efficiency.

  5. Stray light analysis in the TV system for tracking and measuring

    Science.gov (United States)

    Cao, Lei; Chen, Hong-bin; Qiu, Qi; Ren, Ge; Jiang, Yang; Qi, Bo

    2014-08-01

    According to the technical features and requirements of the television imaging system for tracking and measuring, we designed a TV system with focal length of 2800mm, F/11.7 and 2ω(FOV) of 14.2'. The system is compact and easy to fabricate and align, with good image quality. Meanwhile, we performed stray light analysis with ASAP optical software, described stray light suppression techniques used in the TV for tracking and measuring, proposed a method to determine optical properties of the system components and parameters of the scattering model reasonably. We calculated the PST curve of the system for incident angle from -45° to 45°. The results show that when the off-axis angle is larger than the critical incident angle of the sun, PST value is less than 10-8.

  6. Predictive visual tracking based on least absolute deviation estimation

    Institute of Scientific and Technical Information of China (English)

    Rongtai Cai; Yanjie Wang

    2008-01-01

    To cope with the occlusion and intersection between targets and the environment, location prediction is employed in the visual tracking system. Target trace is fitted by sliding subsection polynomials based on least absolute deviation (LAD) estimation, and the future location of target is predicted with the fitted trace. Experiment results show that the proposed location prediction algorithm based on LAD estimation has significant robustness advantages over least square (LS) estimation, and it is more effective than LS-based methods in visual tracking.

  7. Calculating track-based observables for the LHC.

    Science.gov (United States)

    Chang, Hsi-Ming; Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J

    2013-09-06

    By using observables that only depend on charged particles (tracks), one can efficiently suppress pileup contamination at the LHC. Such measurements are not infrared safe in perturbation theory, so any calculation of track-based observables must account for hadronization effects. We develop a formalism to perform these calculations in QCD, by matching partonic cross sections onto new nonperturbative objects called track functions which absorb infrared divergences. The track function Ti(x) describes the energy fraction x of a hard parton i which is converted into charged hadrons. We give a field-theoretic definition of the track function and derive its renormalization group evolution, which is in excellent agreement with the pythia parton shower. We then perform a next-to-leading order calculation of the total energy fraction of charged particles in e+ e-→ hadrons. To demonstrate the implications of our framework for the LHC, we match the pythia parton shower onto a set of track functions to describe the track mass distribution in Higgs plus one jet events. We also show how to reduce smearing due to hadronization fluctuations by measuring dimensionless track-based ratios.

  8. Driver's Face Tracking Based on Improved CAMShift

    Directory of Open Access Journals (Sweden)

    Kamarul Hawari Bin Ghazali

    2013-01-01

    Full Text Available The statistic shows that the number of casualty increase in every year due to road accident related to driver drowsiness. After long journey or sleepless night, vehicle driver will perform some bio-features with regard to drowsiness on them face. It is self-evident that getting location information of head in continuous monitoring and surveillance system rapidly and accurately can help prevent many accidents, and consequently save money and reduce personal suffering. In this paper, according the real situation in vehicle, an improved CAMShift approach is proposed to tracking motion of driver’s head. Results from experiment show the significant performance of proposed approach in driver’s head tracking.

  9. Formation Tracking Based on Approximate Velocities

    Directory of Open Access Journals (Sweden)

    Eduardo Gamaliel Hernandez-Martinez

    2015-12-01

    Full Text Available This paper analyses the formation tracking of groups of mobile robots moving on the plane. A leader robot is chosen to follow a prescribed trajectory whilst the rest, considered as followers, are formed in an open-chain configuration. Two formation-tracking control laws using approximate velocities are proposed, in which some velocities must be communicated between robots in order to ensure the simultaneous preservation of the formation and the following of the group path. The main result is analysis of the convergence of the two proposed control laws. The restriction of inaccurate information occurs in decentralized multi-robot platforms, in which the mobile agents are only able to measure positions and the velocities’ functions are estimated using online numerical methods. A numerical simulation of both controllers in the case of omnidirectional robots is shown. For the case of the unicycle-type robots, real-time experiments of both controllers were implemented and tested.

  10. Large margin classifier-based ensemble tracking

    Science.gov (United States)

    Wang, Yuru; Liu, Qiaoyuan; Yin, Minghao; Wang, ShengSheng

    2016-07-01

    In recent years, many studies consider visual tracking as a two-class classification problem. The key problem is to construct a classifier with sufficient accuracy in distinguishing the target from its background and sufficient generalize ability in handling new frames. However, the variable tracking conditions challenges the existing methods. The difficulty mainly comes from the confused boundary between the foreground and background. This paper handles this difficulty by generalizing the classifier's learning step. By introducing the distribution data of samples, the classifier learns more essential characteristics in discriminating the two classes. Specifically, the samples are represented in a multiscale visual model. For features with different scales, several large margin distribution machine (LDMs) with adaptive kernels are combined in a Baysian way as a strong classifier. Where, in order to improve the accuracy and generalization ability, not only the margin distance but also the sample distribution is optimized in the learning step. Comprehensive experiments are performed on several challenging video sequences, through parameter analysis and field comparison, the proposed LDM combined ensemble tracker is demonstrated to perform with sufficient accuracy and generalize ability in handling various typical tracking difficulties.

  11. MICROCONTROLLER BASED SOLAR-TRACKING SYSTEM AND ITS IMPLEMENTATION

    Directory of Open Access Journals (Sweden)

    Okan BİNGÖL

    2006-02-01

    Full Text Available In this paper, a new micro-controller based solar-tracking system is proposed, implemented and tested. The scheme presented here can be operated as independent of the geographical location of the site of setting up. The system checks the position of the sun and controls the movement of a solar panel so that radiation of the sun comes normally to the surface of the solar panel. The developed-tracking system tracks the sun both in the azimuth as well as in the elevation plane. PC based system monitoring facility is also included in the design.

  12. Tracking energy transfer between light harvesting complex 2 and 1 in photosynthetic membranes grown under high and low illumination.

    Science.gov (United States)

    Lüer, Larry; Moulisová, Vladimíra; Henry, Sarah; Polli, Dario; Brotosudarmo, Tatas H P; Hoseinkhani, Sajjad; Brida, Daniele; Lanzani, Guglielmo; Cerullo, Giulio; Cogdell, Richard J

    2012-01-31

    Energy transfer (ET) between B850 and B875 molecules in light harvesting complexes LH2 and LH1/RC (reaction center) complexes has been investigated in membranes of Rhodopseudomonas palustris grown under high- and low-light conditions. In these bacteria, illumination intensity during growth strongly affects the type of LH2 complexes synthesized, their optical spectra, and their amount of energetic disorder. We used a specially built femtosecond spectrometer, combining tunable narrowband pump with broadband white-light probe pulses, together with an analytical method based on derivative spectroscopy for disentangling the congested transient absorption spectra of LH1 and LH2 complexes. This procedure allows real-time tracking of the forward (LH2 → LH1) and backward (LH2←LH1) ET processes and unambiguous determination of the corresponding rate constants. In low-light grown samples, we measured lower ET rates in both directions with respect to high-light ones, which is explained by reduced spectral overlap between B850 and B875 due to partial redistribution of oscillator strength into a higher energetic exciton transition. We find that the low-light adaptation in R. palustris leads to a reduced elementary backward ET rate, in accordance with the low probability of two simultaneous excitations reaching the same LH1/RC complex under weak illumination. Our study suggests that backward ET is not just an inevitable consequence of vectorial ET with small energetic offsets, but is in fact actively managed by photosynthetic bacteria.

  13. BUPT_PRIS at TREC 2014 Knowledge Base Acceleration Track

    Science.gov (United States)

    2014-11-01

    Abstract This paper describes the system in Vital Filtering and Streaming Slot Filling task of TREC 2014 Knowledge Base Acceleration Track. In the Vital ...can help update a knowledge base like Wikipedia. The KBA2014 includes three tasks: Vital Filtering(VF) task ,Streaming Slot Filling task and Accelerate...Create. The third task is new open track which is not evaluated. For the Vital Filtering task, given a fixed list of target entities from

  14. Improved motion information-based infrared dim target tracking algorithms

    Science.gov (United States)

    Lei, Liu; Zhijian, Huang

    2014-11-01

    Accurate and fast tracking of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. However, under complex backgrounds, such as clutter, varying illumination, and occlusion, the traditional tracking method often converges to a local maximum and loses the real infrared target. To cope with these problems, three improved tracking algorithm based on motion information are proposed in this paper, namely improved mean shift algorithm, improved Optical flow method and improved Particle Filter method. The basic principles and the implementing procedure of these modified algorithms for target tracking are described. Using these algorithms, the experiments on some real-life IR and color images are performed. The whole algorithm implementing processes and results are analyzed, and those algorithms for tracking targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying tracking effectiveness and robustness. Meanwhile, it has high tracking efficiency and can be used for real-time tracking.

  15. Comparative investigation into Viterbi based and multiple hypothesis based track stitching

    CSIR Research Space (South Africa)

    Van der Merwe, LJ

    2016-12-01

    Full Text Available In this study a comparative analysis is performed between a novel Viterbi based and multiple hypothesis based track stitching algorithms. The track fragments in the Viterbi based track stitching algorithm are modelled as nodes in a trellis structure...

  16. Hand Tracking based on Hierarchical Clustering of Range Data

    CERN Document Server

    Cespi, Roberto; Lindner, Marvin

    2011-01-01

    Fast and robust hand segmentation and tracking is an essential basis for gesture recognition and thus an important component for contact-less human-computer interaction (HCI). Hand gesture recognition based on 2D video data has been intensively investigated. However, in practical scenarios purely intensity based approaches suffer from uncontrollable environmental conditions like cluttered background colors. In this paper we present a real-time hand segmentation and tracking algorithm using Time-of-Flight (ToF) range cameras and intensity data. The intensity and range information is fused into one pixel value, representing its combined intensity-depth homogeneity. The scene is hierarchically clustered using a GPU based parallel merging algorithm, allowing a robust identification of both hands even for inhomogeneous backgrounds. After the detection, both hands are tracked on the CPU. Our tracking algorithm can cope with the situation that one hand is temporarily covered by the other hand.

  17. An Improved Variable-Frequency Drive Based on Current Tracking

    Directory of Open Access Journals (Sweden)

    Zhiwei He

    2013-11-01

    Full Text Available Variable frequency devices are widely used in many power systems. A current tracking based VFD is proposed in this paper. The output current is firstly fed back and compared with a standard sine wave, the difference of them is then used for a PI regulator to control the PWM signal, so as to change the output current accordingly to make it approach the standard sine wave. Simulation and experiments results show that the current tracking VFD not only has a fast dynamic response, high current tracking precision, current limiting ability, but also has small distortion of the output sine wave current and low loss of the motor.    

  18. Automated image-based tracking and its application in ecology.

    Science.gov (United States)

    Dell, Anthony I; Bender, John A; Branson, Kristin; Couzin, Iain D; de Polavieja, Gonzalo G; Noldus, Lucas P J J; Pérez-Escudero, Alfonso; Perona, Pietro; Straw, Andrew D; Wikelski, Martin; Brose, Ulrich

    2014-07-01

    The behavior of individuals determines the strength and outcome of ecological interactions, which drive population, community, and ecosystem organization. Bio-logging, such as telemetry and animal-borne imaging, provides essential individual viewpoints, tracks, and life histories, but requires capture of individuals and is often impractical to scale. Recent developments in automated image-based tracking offers opportunities to remotely quantify and understand individual behavior at scales and resolutions not previously possible, providing an essential supplement to other tracking methodologies in ecology. Automated image-based tracking should continue to advance the field of ecology by enabling better understanding of the linkages between individual and higher-level ecological processes, via high-throughput quantitative analysis of complex ecological patterns and processes across scales, including analysis of environmental drivers.

  19. Passive Target Tracking Based on Current Statistical Model

    Institute of Scientific and Technical Information of China (English)

    DENG Xiao-long; XIE Jian-ying; YANG Yu-pu

    2005-01-01

    Bearing-only passive tracking is regarded as a nonlinear hard tracking problem. There are still no completely good solutions to this problem until now. Based on current statistical model, the novel solution to this problem utilizing particle filter (PF) and the unscented Kalman filter (UKF) is proposed. The new solution adopts data fusion from two observers to increase the observability of passive tracking. It applies the residual resampling step to reduce the degeneracy of PF and it introduces the Markov Chain Monte Carlo methods (MCMC) to reduce the effect of the "sample impoverish". Based on current statistical model, the EKF, the UKF and particle filter with various proposal distributions are compared in the passive tracking experiments with two observers. The simulation results demonstrate the good performance of the proposed new filtering methods with the novel techniques.

  20. Disturbance observer based position tracking of electro-hydraulic actuator

    Institute of Scientific and Technical Information of China (English)

    国凯; 魏建华; 田启岩

    2015-01-01

    A nonlinear controller based on an extended second-order disturbance observer is presented to track desired position for an electro-hydraulic single-rod actuator in the presence of both external disturbances and parameter uncertainties. The proposed extended second-order disturbance observer deals with not only the external perturbations, but also parameter uncertainties which are commonly regarded as lumped disturbances in previous researches. Besides, the outer position tracking loop is designed with cylinder load pressure as output; and the inner pressure control loop provides the hydraulic actuator the characteristic of a force generator. The stability of the closed-loop system is provided based on Lyapunov theory. The performance of the controller is verified through simulations and experiments. The results demonstrate that the proposed nonlinear position tracking controller, together with the extended second-order disturbance observer, gives an excellent tracking performance in the presence of parameter uncertainties and external disturbance.

  1. Cluster-based localization and tracking in ubiquitous computing systems

    CERN Document Server

    Martínez-de Dios, José Ramiro; Torres-González, Arturo; Ollero, Anibal

    2017-01-01

    Localization and tracking are key functionalities in ubiquitous computing systems and techniques. In recent years a very high variety of approaches, sensors and techniques for indoor and GPS-denied environments have been developed. This book briefly summarizes the current state of the art in localization and tracking in ubiquitous computing systems focusing on cluster-based schemes. Additionally, existing techniques for measurement integration, node inclusion/exclusion and cluster head selection are also described in this book.

  2. A Moving Human Tracking Approach Based on Semantic Interaction

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ning; FANG Bao-hong; SUN Fu-liang

    2007-01-01

    In order to deal with partical occlusion, a semantic interaction based moving human tracking approach is put forward. Firstly human is modeled as moving blobs which are described as blob descriptions. Then moving blobs are updated and verified by projecting these descriptions. The approach exploits improved fast gauss transform and chooses source and target samples to reduce compute cost. Multi-moving human can be tracked simply and part occlusion can be done well.

  3. Improved Likelihood Function in Particle-based IR Eye Tracking

    DEFF Research Database (Denmark)

    Satria, R.; Sorensen, J.; Hammoud, R.

    2005-01-01

    In this paper we propose a log likelihood-ratio function of foreground and background models used in a particle filter to track the eye region in dark-bright pupil image sequences. This model fuses information from both dark and bright pupil images and their difference image into one model. Our...... performance in challenging sequences with test subjects showing large head movements and under significant light conditions....

  4. Track-based event recognition in a realistic crowded environment

    Science.gov (United States)

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

    2014-10-01

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

  5. Video Based Moving Object Tracking by Particle Filter

    Directory of Open Access Journals (Sweden)

    Md. Zahidul Islam

    2009-03-01

    Full Text Available Usually, the video based object tracking deal with non-stationary image stream that changes over time. Robust and Real time moving object tracking is a problematic issue in computer vision research area. Most of the existing algorithms are able to track only inpredefined and well controlled environment. Some cases, they don’t consider non-linearity problem. In our paper, we develop such a system which considers color information, distance transform (DT based shape information and also nonlinearity. Particle filtering has been proven very successful for non-gaussian and non-linear estimation problems. We examine the difficulties of video based tracking and step by step we analyze these issues. In our firstapproach, we develop the color based particle filter tracker that relies on the deterministic search of window, whose color content matches a reference histogram model. A simple HSV histogram-based color model is used to develop this observation system. Secondly, wedescribe a new approach for moving object tracking with particle filter by shape information. The shape similarity between a template and estimated regions in the video scene is measured by their normalized cross-correlation of distance transformed images. Our observation system of particle filter is based on shape from distance transformed edge features. Template is created instantly by selecting any object from the video scene by a rectangle. Finally, inthis paper we illustrate how our system is improved by using both these two cues with non linearity.

  6. Retinal Image-Based Eye-Tracking Using the Tracking Scanning Laser Ophthalmoscope

    Science.gov (United States)

    Sheehy, Christy Kathleen

    The tracking scanning laser ophthalmoscope (TSLO) was designed, built and characterized for high-resolution eye-tracking, imaging, and targeted retinal stimulus delivery. Eye-tracking is done via an image-based software program that monitors the image of the retina over time while simultaneously logging the displacements of the eye. Currently, this system is the most accurate, fast and functional eye-tracking system used in a standard ophthalmic instrument. The TSLO has the ability to non-invasively track the eye at 960 Hz (with an accuracy of 0.2 arcminutes or roughly 1 micron) and present stimuli to the retina at the resolution of single cone photoreceptors (0.66 arcminutes, which is roughly 3 microns). The combination of structural imaging and functional testing allows one to begin to more thoroughly understand retinal disease progression, as well probe specific retinal locations in order to test new treatment efficacies. This level of accuracy is unprecedented in the clinic and is crucial when monitoring minute changes in eye motion, structure, and function. Additionally, the system is capable of providing external eye-tracking for other high-resolution imaging systems, such as optical coherence tomography (OCT) and adaptive optics scanning laser ophthalmoscope (AOSLO) systems through the active steering of an imaging beam. This feature allows the imaging raster or stimuli to stay on target during fixational eye motion. This dissertation steps through all of the above-mentioned uses of the TSLO and further elaborates on the optimal design and system test performance capabilities of the system.

  7. Passivated gel electrophoresis of charged nanospheres by light-scattering video tracking.

    Science.gov (United States)

    Zhu, Xiaoming; Mason, Thomas G

    2014-08-15

    Gel electrophoresis (gel-EP) has been used for decades to separate charged biopolymers, such as DNA, RNA, and proteins, yet propagation of other charged colloidal objects, such as nanoparticles, during gel-EP has been studied comparatively little. Simply introducing anionic nanoparticles, such as sulfate-stabilized polystyrene nanospheres, in standard large-pore agarose gels commonly used for biomolecules does not automatically ensure propagation or size-separation because attractive interactions can exist between the gel and the nanoparticles. Whereas altering the surfaces of the nanoparticles is a possible solution, here, by contrast, we show that treating a common type I-A low-electroendoosmosis agarose gel with a passivation agent, such as poly-(ethyleneglycol), enables charged nanoparticles to propagate through large-pore passivated gels in a highly reproducible manner. Moreover, by taking advantage of the significant optical scattering from the nanoparticles, which is not easily measurable for biopolymers, relative to scattering from the gel, we perform real-time, light-scattering, video-tracking gel-EP. Continuous optical measurements of the propagation of bands of uniformly sized nanospheres in passivated gels provides the propagation distance, L, and velocity, v, as a function of time for different sphere radii, electric field strengths, gel concentrations, and passivation agent concentrations. The steady-state particle velocities vary linearly with applied electric field strength, E, for small E, but these velocities become non-linear for larger E, suggesting that strongly driven nanoparticles can become elastically trapped in the smaller pores of the gel, which act like blind holes, in a manner that thermal fluctuations cannot overcome. Based on this assumption, we introduce a simple model that fits the measured v(E) in both linear and non-linear regimes over a relevant range of applied voltages. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Video-based Chinese Input System via Fingertip Tracking

    Directory of Open Access Journals (Sweden)

    Chih-Chang Yu

    2012-10-01

    Full Text Available In this paper, we propose a system to detect and track fingertips online and recognize Mandarin Phonetic Symbol (MPS for user-friendly Chinese input purposes. Using fingertips and cameras to replace pens and touch panels as input devices could reduce the cost and improve the ease-of-use and comfort of computer-human interface. In the proposed framework, particle filters with enhanced appearance models are applied for robust fingertip tracking. Afterwards, MPS combination recognition is performed on the tracked fingertip trajectories using Hidden Markov Models. In the proposed system, the fingertips of the users could be robustly tracked. Also, the challenges of entering, leaving and virtual strokes caused by video-based fingertip input can be overcome. Experimental results have shown the feasibility and effectiveness of the proposed work.

  9. Head Tracking Based Avatar Control for Virtual Environment Teamwork Training

    Directory of Open Access Journals (Sweden)

    Stefan Marks

    2012-12-01

    Full Text Available Virtual environments (VE are gaining in popularity and are increasingly used for teamwork training purposes, e.g., for medical teams. One shortcoming of modern VEs is that nonverbal communication channels, essential for teamwork, are not supported well. We address this issue by using an inexpensive webcam to track the user's head. This tracking information is used to control the head movement of the user's avatar, thereby conveying head gestures and adding a nonverbal communication channel. We conducted a user study investigating the influence of head tracking based avatar control on the perceived realism of the VE and on the performance of a surgical teamwork training scenario. Our results show that head tracking positively influences the perceived realism of the VE and the communication, but has no major influence on the training outcome.

  10. Lighting of the cycle track and footpath along the D 984

    CERN Multimedia

    Relations with the Host States Service

    2004-01-01

    The communes of Prévessin-Moëns and Saint-Genis-Pouilly have informed CERN that work to install lighting on the cycle track and footpath along the D 984 road between the Prévessin-RN 84/Meyrin-Route customs post and the roundabout at the western end of CERN's Meyrin site is to start shortly. You are requested to be especially careful while the work, which is scheduled to last around 3 weeks but will not affect access to SM12, is in progress. Relations with the Host States Service Tel. 72848

  11. Lighting of the cycle track and footpath along the D 984

    CERN Multimedia

    Relations with the Host States Service

    2004-01-01

    The communes of Prévessin-Moëns and Saint-Genis-Pouilly have informed CERN that work to install lighting on the cycle track and footpath along the D 984 road between the Prévessin-RN 84/Meyrin-Route customs post and the roundabout at the western end of CERN's Meyrin site is to start shortly. You are requested to be especially careful while the work, which is scheduled to last around 3 weeks but will not affect access to SM12, is in progress.Relations with the Host States Service Tel. 72848

  12. Research on the acquisition and tracking simulation system of light beacon in satellite-ground optical communications

    Institute of Scientific and Technical Information of China (English)

    ZUO Tao; AI Yong; HUANG Hai-bo; SU Gui-bo

    2010-01-01

    @@ The study on the acquisition and tracking simulation system in satellite-ground optical communications is presented here.By applying global positioning system(GPS)coordinate calculation,the time needed in initial acquisition of light beacon can be reduced largely.Smith predictor is applied to compensate the mechanical hysteresis of tracking system and to improve the dynamic performance of the system.Tracking experiments over a i 6 km distance on the ground are conducted to verify the tracking of light beacon in satellite-ground optical communications.The standard deviation of horizontal coordinates is 35.3568 μrad and the maximum offset is 209.3675 μrad in stable tracking.

  13. Level-1 pixel based tracking trigger algorithm for LHC upgrade

    Science.gov (United States)

    Moon, C.-S.; Savoy-Navarro, A.

    2015-10-01

    The Pixel Detector is the innermost detector of the tracking system of the Compact Muon Solenoid (CMS) experiment at CERN Large Hadron Collider (LHC) . It precisely determines the interaction point (primary vertex) of the events and the possible secondary vertexes due to heavy flavours (b and c quarks); it is part of the overall tracking system that allows reconstructing the tracks of the charged particles in the events and combined with the magnetic field to measure their momentum. The pixel detector allows measuring the tracks in the region closest to the interaction point. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is currently being studied for the LHC upgrade. An important goal is developing real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of the rare physics events from the large pile-up (PU) of events. The goal of adding the pixel information already at the real-time level of the selection is to help reducing the total level-1 trigger rate while keeping an high selection capability. This is quite an innovative and challenging objective for the experiments upgrade for the High Luminosity LHC (HL-LHC) . The special case here addressed is the CMS experiment. This document describes exercises focusing on the development of a fast pixel track reconstruction where the pixel track matches with a Level-1 electron object using a ROOT-based simulation framework.

  14. Observations of short-range, high-LET recoil tracks in CR-39 plastic nuclear track detector by visible light microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Benton, E.R., E-mail: eric.benton@okstate.ed [Dept. of Physics, Oklahoma State University, 1110 S. Innovation Way, 100, Stillwater, OK 74078 (United States); Johnson, C.E. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); DeWitt, J. [Dept. of Physics, Oklahoma State University, 1110 S. Innovation Way, 100, Stillwater, OK 74078 (United States); Yasuda, N. [National Institute of Radiological Sciences, Chiba (Japan); Benton, E.V. [Dept. of Physics, University of San Francisco, San Francisco, CA 94117 (United States); Moyers, M.H. [Proton Therapy, Inc., Colton, CA 92324 (United States); Frank, A.L. [Dept. of Physics, University of San Francisco, San Francisco, CA 94117 (United States)

    2011-05-15

    Using standard visible light microscopy, we are able to observe particle tracks produced by <10 {mu}m range target fragment recoils in CR-39 plastic nuclear track detector (PNTD) following short chemical etching (bulk etch B {<=}1 {mu}m). In accelerator irradiations, targets of varying composition, including a number of elemental targets of high Z, were exposed in contact with layers of CR-39 PNTD to beams of 60 MeV, 230 MeV, and 1 GeV protons at doses of 10-50 Gy. Chemical etching of CR-39 under standard conditions (50 {sup o}C, 6.25 N NaOH) for 2-4 h (removed layer B = 0.5-1.0 {mu}m) yielded secondary track densities of 10{sup 5}-10{sup 6} cm{sup -2} observable under a standard optical microscope with 500x-800x magnification. Ordinarily such a short duration etch would not be expected to enlarge the tracks sufficiently for them to be resolved by visible light optics. However, due to the short-range of the particles, a longer chemical processing would have over-etched the tracks until they were no longer recognizable. The tracks we observe in CR-39 PNTD irradiated in these experiments are the result of residual heavy recoil fragments returning to equilibrium via evaporation processes following proton-induced knock out of light particles via preequilibrium processes. Because the heavy recoil particles are very near the end of their ranges (i.e. in the Bragg peak), their LET is extremely high and changes rapidly. Consequently, the tracks they produce in CR-39 PNTD often take the form of long tubes rather than the conical etch pits produced by higher energy particles.

  15. Analysis of the circular track experiment measuring the one-way speed of light

    OpenAIRE

    Philip, Evan John

    2012-01-01

    All experiments attempting to verify the invariance of speed of light directly are based on two-way speed measurement. The challenge in one-way speed measurement, the requirement of spatially separated synchronised clocks, can be possibly circumvented by measuring the speed of light travelling in a closed path. An apparent violation of the invariance principle has been recently reported in the first experiment attempting to measure the one-way speed of light utilising this concept. This exper...

  16. 2000 fps multi-object tracking based on color histogram

    Science.gov (United States)

    Gu, Qingyi; Takaki, Takeshi; Ishii, Idaku

    2012-06-01

    In this study, we develop a real-time, color histogram-based tracking system for multiple color-patterned objects in a 512×512 image at 2000 fps. Our system can simultaneously extract the positions, areas, orientation angles, and color histograms of multiple objects in an image using the hardware implementation of a multi-object, color histogram extraction circuit module on a high-speed vision platform. It can both label multiple objects in an image consisting of connected components and calculate their moment features and 16-bin hue-based color histograms using cell-based labeling. We demonstrate the performance of our system by showing several experimental results: (1) tracking of multiple color-patterned objects on a plate rotating at 16 rps, and (2) tracking of human hand movement with two color-patterned drinking bottles.

  17. Parameterization-based tracking for the P2 experiment

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-01

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

  18. Level-1 pixel based tracking trigger algorithm for LHC upgrade

    CERN Document Server

    Moon, Chang-Seong

    2015-01-01

    The Pixel Detector is the innermost detector of the tracking system of the Compact Muon Solenoid (CMS) experiment at CERN Large Hadron Collider (LHC). It precisely determines the interaction point (primary vertex) of the events and the possible secondary vertexes due to heavy flavours ($b$ and $c$ quarks); it is part of the overall tracking system that allows reconstructing the tracks of the charged particles in the events and combined with the magnetic field to measure their impulsion. The pixel detector allows measuring the tracks in the region closest to the interaction point. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is currently being studied for the LHC upgrade. An important goal is developing real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of the rare physics events from the large pile-up (P...

  19. CamShift Tracking Method Based on Target Decomposition

    Directory of Open Access Journals (Sweden)

    Chunbo Xiu

    2015-01-01

    Full Text Available In order to avoid the inaccurate location or the failure tracking caused by the occlusion or the pose variation, a novel tracking method is proposed based on CamShift algorithm by decomposing the target into multiple subtargets for location separately. Distance correlation matrices are constructed by the subtarget sets in the template image and the scene image to evaluate the correctness of the location results. The error locations of the subtargets can be corrected by resolving the optimization function constructed according to the relative positions among the subtargets. The directions and sizes of the correctly located subtargets with CamShift algorithm are updated to reduce the disturbance of the background in the tracking progress. Simulation results show that the method can perform the location and tracking of the target and has better adaptability to the scaling, translation, rotation, and occlusion. Furthermore, the computational cost of the method increases slightly, and its average tracking computational time of the single frame is less than 25 ms, which can meet the real-time requirement of the TV tracking system.

  20. Nanoresonator based dielectric surfaces for light manipulation

    NARCIS (Netherlands)

    Silvestri, F.; Pisano, E.; Gerini, G.; Lancellotti, V.; Galdi, V.

    2015-01-01

    In the last years, increasing interest has grown on the synthesis of light-weight, miniaturized surfaces for light manipulation based on metamaterials. These surfaces can be easily integrated in photonic systems and they can be used as high numerical aperture lenses, light-deflection surfaces and

  1. 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

  2. A paper based inkjet printed real time location tracking TAG

    KAUST Repository

    Farooqui, Muhammad Fahad

    2013-06-01

    This paper presents, for the first time, an inkjet printed, wearable, low-cost, light weight and miniaturized real time locating TAG on an ordinary photo-paper. The 29 grams, 9 cm×8 cm×0.5 cm TAG integrates a GPS/GSM module, a microcontroller with on-paper GPS and GSM antennas. A novel monopole antenna with an L shaped slit is introduced to achieve the required circular polarization for the GPS band. Issues related to integration of active components (e.g. BGA chip) on inkjet-printed paper substrates are discussed. The system enables location tracking through a user-friendly interface accessible through all internet enabled devices. Field tests show an update interval of 15 sec, stationary position error of 6.2m and real time tracking error of 4.7m which is 4 times better than the state-of-the-art. Due to the flexible nature of the paper substrate, the TAG can be designed for different shapes such as a wrist band for child tracking or a collar band for pet tracking applications. © 2013 IEEE.

  3. Development a Vision Based Seam Tracking System for None Destructive Testing Machines

    Directory of Open Access Journals (Sweden)

    Nasser moradi

    2013-04-01

    Full Text Available The automatic weld seam tracking is an important challenge in None Destructive Testing (NDT systems for welded pipe inspection. In this Study, a machine vision based seam tracker, is developed and implemented, instead of old electro-mechanical system. A novel algorithm based on the weld image centered is presented, to reduce Environment conditions and improve the seam tracking accuracy. The weld seam images are taken by a camera arranged ahead of the machine and the centered is extracted as a parameter to detect the weld position, and offset between this point and central axis is computed and used as control parameter of servomotors. Adaptive multi step segmentation t technique is employed to increase the probable of real edge of the welds and improve the line fitting accuracy. This new approach offers some important technical advantages over the existing solutions to weld seam detection: Its based on natural light and does not need any auxiliary light. The adaptive threshold segmentation technique applied, decrease Environmental lighting condition. Its accurate and stable in real time NDT testing machines. After a series of experiments in real industrial environment, it is demonstrated that accuracy of this method can improve the quality of NDT machines. The average tracking error is 1.5 pixels approximately 0.25mm..

  4. A Geometric Particle Filter for Template-Based Visual Tracking.

    Science.gov (United States)

    Junghyun Kwon; Hee Seok Lee; Park, Frank C; Kyoung Mu Lee

    2014-04-01

    Existing approaches to template-based visual tracking, in which the objective is to continuously estimate the spatial transformation parameters of an object template over video frames, have primarily been based on deterministic optimization, which as is well-known can result in convergence to local optima. To overcome this limitation of the deterministic optimization approach, in this paper we present a novel particle filtering approach to template-based visual tracking. We formulate the problem as a particle filtering problem on matrix Lie groups, specifically the three-dimensional Special Linear group SL(3) and the two-dimensional affine group Aff(2). Computational performance and robustness are enhanced through a number of features: (i) Gaussian importance functions on the groups are iteratively constructed via local linearization; (ii) the inverse formulation of the Jacobian calculation is used; (iii) template resizing is performed; and (iv) parent-child particles are developed and used. Extensive experimental results using challenging video sequences demonstrate the enhanced performance and robustness of our particle filtering-based approach to template-based visual tracking. We also show that our approach outperforms several state-of-the-art template-based visual tracking methods via experiments using the publicly available benchmark data set.

  5. Vision-based multiple vehicle detection and tracking at nighttime

    Science.gov (United States)

    Xu, Wencong; Liu, Hai

    2011-08-01

    In this paper, we develop a robust vision-based approach for real-time traffic data collection at nighttime. The proposed algorithm detects and tracks vehicles through detection and location of vehicle headlights. First, we extract headlights candidates by an adaptive image segmentation algorithm. Then we group headlights candidates that belong to the same vehicle by spatial clustering and generate vehicle hypotheses by rule-based reasoning. The potential vehicles are then tracked over frames by region search and pattern analysis methods. The spatial and temporal continuity extracted from tracking process is used to confirm vehicle's presence. To handle problem of occlusions, we apply Kalman Filter to motion estimation. We test the algorithm on the video clips of nighttime traffic under different conditions. The experimental results show that real-time vehicle counting and tacking for multi-lanes are achieved and the total detection rate is above 96%.

  6. Group Targets Tracking Using Multiple Models GGIW-CPHD Based on Best-Fitting Gaussian Approximation and Strong Tracking Filter

    Directory of Open Access Journals (Sweden)

    Yun Wang

    2016-01-01

    Full Text Available Gamma Gaussian inverse Wishart cardinalized probability hypothesis density (GGIW-CPHD algorithm was always used to track group targets in the presence of cluttered measurements and missing detections. A multiple models GGIW-CPHD algorithm based on best-fitting Gaussian approximation method (BFG and strong tracking filter (STF is proposed aiming at the defect that the tracking error of GGIW-CPHD algorithm will increase when the group targets are maneuvering. The best-fitting Gaussian approximation method is proposed to implement the fusion of multiple models using the strong tracking filter to correct the predicted covariance matrix of the GGIW component. The corresponding likelihood functions are deduced to update the probability of multiple tracking models. From the simulation results we can see that the proposed tracking algorithm MM-GGIW-CPHD can effectively deal with the combination/spawning of groups and the tracking error of group targets in the maneuvering stage is decreased.

  7. Bidirectional MIMO Channel Tracking Based on PASTd and Performance Evaluation

    Science.gov (United States)

    Ehrenberg, Livnat; Gannot (Eurasipmember), Sharon; Shayevitz, Ofer; Leshem, Amir; Zehavi, Ephraim

    2010-12-01

    We consider a bidirectional time division duplex (TDD) multiple-input multiple-output (MIMO) communication system with time-varying channel and additive white Gaussian noise (AWGN). A blind bidirectional channel tracking algorithm, based on the projection approximation subspace tracking (PAST) algorithm, is applied in both terminals. The resulting singular value decomposition (SVD) of the channel matrix is then used to approximately diagonalize the channel. The proposed method is applied to an orthogonal frequency-division multiplexing-(OFDM-)MIMO setting with a typical indoor time-domain reflection model. The computational cost of the proposed algorithm, compared with other state-of-the-art algorithms, is relatively small. The Kalman filter is utilized for establishing a benchmark for the obtained performance of the proposed tracking algorithm. The performance degradation relative to a full channel state information (CSI) due to the application of the tracking algorithm is evaluated in terms of average effective rate and the outage probability and compared with alternative tracking algorithms. The obtained results are also compared with a benchmark obtained by the Kalman filter with known input signal and channel characteristics. It is shown that the expected degradation in performance of frequency-domain algorithms (which do not exploit the smooth frequency response of the channel) is only minor compared with time-domain algorithms in a range of reasonable signal-to-noise ratio (SNR) levels. The proposed bidirectional frequency-domain tracking algorithm, proposed in this paper, is shown to attain communication rates close to the benchmark and to outperform a competing algorithm. The paper is concluded by evaluating the proposed blind tracking method in terms of the outage probability and the symbol error rate (SER) versus. SNR for binary phase shift keying (BPSK) and 4-Quadrature amplitude modulation (QAM) constellations.

  8. Bidirectional MIMO Channel Tracking Based on PASTd and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Shayevitz Ofer

    2010-01-01

    Full Text Available Abstract We consider a bidirectional time division duplex (TDD multiple-input multiple-output (MIMO communication system with time-varying channel and additive white Gaussian noise (AWGN. A blind bidirectional channel tracking algorithm, based on the projection approximation subspace tracking (PAST algorithm, is applied in both terminals. The resulting singular value decomposition (SVD of the channel matrix is then used to approximately diagonalize the channel. The proposed method is applied to an orthogonal frequency-division multiplexing-(OFDM-MIMO setting with a typical indoor time-domain reflection model. The computational cost of the proposed algorithm, compared with other state-of-the-art algorithms, is relatively small. The Kalman filter is utilized for establishing a benchmark for the obtained performance of the proposed tracking algorithm. The performance degradation relative to a full channel state information (CSI due to the application of the tracking algorithm is evaluated in terms of average effective rate and the outage probability and compared with alternative tracking algorithms. The obtained results are also compared with a benchmark obtained by the Kalman filter with known input signal and channel characteristics. It is shown that the expected degradation in performance of frequency-domain algorithms (which do not exploit the smooth frequency response of the channel is only minor compared with time-domain algorithms in a range of reasonable signal-to-noise ratio (SNR levels. The proposed bidirectional frequency-domain tracking algorithm, proposed in this paper, is shown to attain communication rates close to the benchmark and to outperform a competing algorithm. The paper is concluded by evaluating the proposed blind tracking method in terms of the outage probability and the symbol error rate (SER versus. SNR for binary phase shift keying (BPSK and 4-Quadrature amplitude modulation (QAM constellations.

  9. A configurable tracking algorithm to detect cosmic muon tracks for the CMS-RPC based technical trigger

    CERN Document Server

    Rajan, R T; Loddo, F; Maggi, M; Ranieri, A; Abbrescia, M; Guida, R; Iaselli, G; Nuzzo, S; Pugliese, G; Roselli, G; Trentadue, R; Tupputi, b, S; Benussi, L; Bertani, M; Bianco, S; Fabbri, F; Cavallo, N; Cimmino, e, A; Lomidze, D; Noli, P; Paolucci, P; Piccolo, D; Polese, G; Sciacca, C; Baesso, g, P; Belli, G; Necchi, M; Ratti, S P; Pagano, D; Vitulo, P; Viviani, C; Dimitrov, A; Litov, L; Pavlov, B; Petkov, P; Genchev, V; Iaydjiev, P; Bunkowski, K; Kierzkowski, K; Konecki, M; Kudla, I; Pietrusinski, M; Pozniak, K

    2009-01-01

    In the CERN CMS experiment at LHC Collider special trigger signals called Technical Triggers will be used for the purpose of test and calibration. The Resistive Plate Chambers (RPC) based Technical Trigger system is a part of the CMS muon trigger system and is designed to detect cosmic muon tracks. It is based on two boards, namely RBC (RPC Balcony Collector) and TTU (Technical Trigger Unit). The proposed tracking algorithm (TA) written in VHDL and implemented in the TTU board detects single or multiple cosmic muon tracks at every bunch crossing along with their track lengths and corresponding chamber coordinates. The TA implementation in VHDL and its preliminary simulation results are presented.

  10. Global point tracking based panoramic image stabilization system

    Institute of Scientific and Technical Information of China (English)

    朱娟娟; 郭宝龙; 吴宪祥

    2009-01-01

    A novel image stabilization system is presented,which consists of a global feature point tracking based motion estimation,a Kalman filtering based motion smoothing and an image mosaic based panoramic compensation.The global motion is estimated using feature point matching and iteration with the least-square method.Then,the Kalman filter is applied to smooth the original motion vectors to effectively alleviate unwanted camera vibrations and follow the intentional camera scan.Lastly,the loss information of im...

  11. GPU Accelerated Likelihoods for Stereo-Based Articulated Tracking

    DEFF Research Database (Denmark)

    Friborg, Rune Møllegaard; Hauberg, Søren; Erleben, Kenny

    For many years articulated tracking has been an active research topic in the computer vision community. While working solutions have been suggested, computational time is still problematic. We present a GPU implementation of a ray-casting based likelihood model that is orders of magnitude faster...

  12. Approximate Bayesian methods for kernel-based object tracking

    NARCIS (Netherlands)

    Zivkovic, Z.; Cemgil, A.T.; Kröse, B.

    2009-01-01

    A framework for real-time tracking of complex non-rigid objects is presented. The object shape is approximated by an ellipse and its appearance by histogram based features derived from local image properties. An efficient search procedure is used to find the image region with a histogram most simila

  13. GPU accelerated likelihoods for stereo-based articulated tracking

    DEFF Research Database (Denmark)

    Friborg, Rune Møllegaard; Hauberg, Søren; Erleben, Kenny

    2010-01-01

    For many years articulated tracking has been an active research topic in the computer vision community. While working solutions have been suggested, computational time is still problematic. We present a GPU implementation of a ray-casting based likelihood model that is orders of magnitude faster...

  14. State of the Art in Tracking Based Business

    NARCIS (Netherlands)

    Kajosaari, R.; Langius, E.; Holmström, J.

    2007-01-01

    Item-centric control and information management is a potential solution to establish economically and practically feasible Concurrent Enterprises. The economical feasibility of item-centric tracking is based on recent technological developments for monitoring the material flow on the item-level inst

  15. Optimization of preventive condition-based tamping for railway tracks

    DEFF Research Database (Denmark)

    Wen, Min; Li, Rui; Salling, Kim Bang

    2016-01-01

    This work considers the scheduling of railway preventive condition-based tamping, which is the maintenance operation performed to restore the track irregularities to ensure both safety and comfort for passengers and freight. The problem is to determine when to perform the tamping on which section...

  16. Robust kernel-based tracking algorithm with background contrasting

    Institute of Scientific and Technical Information of China (English)

    Rongli Liu; Zhongliang Jing

    2012-01-01

    The mean-shift algorithm has achieved considerable success in object tracking due to its simplicity and efficiency. Color histogram is a common feature in the description of an object. However, the kernel-based color histogram may not have the ability to discriminate the object from clutter background. To boost the discriminating ability of the feature, based on background contrasting, this letter presents an improved Bhattacharyya similarity metric for mean-shift tracking. Experiments show that the proposed tracker is more robust in relation to background clutter.%The mean-shift algorithm has achieved considerable success in object tracking due to its simplicity and efficiency.Color histogram is a common feature in the description of an object.However,the kernel-based color histogram may not have the ability to discriminate the object from clutter background.To boost the discriminating ability of the feature,based on background contrasting,this letter presents an improved Bhattacharyya similarity metric for mean-shift tracking.Experiments show that the proposed tracker is more robust in relation to background clutter.

  17. Video-based eye tracking for neuropsychiatric assessment.

    Science.gov (United States)

    Adhikari, Sam; Stark, David E

    2017-01-01

    This paper presents a video-based eye-tracking method, ideally deployed via a mobile device or laptop-based webcam, as a tool for measuring brain function. Eye movements and pupillary motility are tightly regulated by brain circuits, are subtly perturbed by many disease states, and are measurable using video-based methods. Quantitative measurement of eye movement by readily available webcams may enable early detection and diagnosis, as well as remote/serial monitoring, of neurological and neuropsychiatric disorders. We successfully extracted computational and semantic features for 14 testing sessions, comprising 42 individual video blocks and approximately 17,000 image frames generated across several days of testing. Here, we demonstrate the feasibility of collecting video-based eye-tracking data from a standard webcam in order to assess psychomotor function. Furthermore, we were able to demonstrate through systematic analysis of this data set that eye-tracking features (in particular, radial and tangential variance on a circular visual-tracking paradigm) predict performance on well-validated psychomotor tests. © 2017 New York Academy of Sciences.

  18. SCU at TREC 2014 Knowledge Base Acceleration Track

    Science.gov (United States)

    2014-11-01

    SCU at TREC 2014 Knowledge Base Acceleration Track Hung Nguyen, Yi Fang Department of Computer Engineering Santa Clara University 500 El Camino ...University,Department of Computer Engineering,500 El Camino Real,Santa Clara,CA,95053 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING

  19. Fast neural-net based fake track rejection

    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, is fast enough to fit into the CPU time budget of the software trigger farm. It allows reducing the fake rate and consequently 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.

  20. Vehicle detection and tracking based on phase-correlation

    Institute of Scientific and Technical Information of China (English)

    Yi He(何毅); Xin Yang(杨新)

    2004-01-01

    This paper presents vehicle detection and tracking algorithms based on real-time background (RTB) and phase-correlation (PC) in the video sequence of urban highway with fixed camera. Firstly moving objects are obtained by subtracting RTB from serial images. After classification, PC is used to determine corresponding regions of moving objects between consecutive frames. The problems of vehicles' merging and splitting, sudden stop, and restart are also considered. Experiments show that the method is practical and can realize real-time detection and tracking of vehicles on highway.

  1. Overall test evaluation based on trajectory tracking data

    Institute of Scientific and Technical Information of China (English)

    王正明; 段晓君

    2001-01-01

    According to the trajectory characteristics of ballistic missile, a reduced parameter model is constructed based on difference between telemetry trajectory and trajectory tracking data. By virtue of Bayesian theory and data fusion technique, a new test evaluation method is put forth, which can make full use of the trajectory tracking data, shooting range test data and relevant information. Since the impact point can be derived from trajectory difference and its kinetic characteristics, evaluation of the impact point is a special case of this method. The accurate evaluation and the accuracy of evaluation results can be provided by the new method.

  2. Tensor-SIFT based Earth Mover's Distance for Contour Tracking

    CERN Document Server

    Li, Peihua

    2010-01-01

    Contour tracking in adverse environments is a challenging problem due to cluttered background, illumination variation, occlusion, and noise, among others. This paper presents a robust contour tracking method by contributing to some of the key issues involved, including (a) a region functional formulation and its optimization; (b) design of a robust and effective feature; and (c) development of an integrated tracking algorithm. First, we formulate a region functional based on robust Earth Mover's distance (EMD) with kernel density for distribution modeling, and propose a two-phase method for its optimization. In the first phase, letting the candidate contour be fixed, we express EMD as the transportation problem and solve it by the simplex algorithm. Next, using the theory of shape derivative, we make a perturbation analysis of the contour around the best solution to the transportation problem. This leads to a partial differential equation (PDE) that governs the contour evolution. Second, we design a novel and...

  3. Photochemical reflectance ratio for tracking light use efficiency for sunlit leaves in two forest types

    Science.gov (United States)

    Zheng, Ting; Chen, Jing M.

    2017-01-01

    The estimation of maximum carboxylation rate (Vcmax)-a critical determinant of the terrestrial carbon simulation-over space remains a challenging task. Inverting the Vcmax through the sunlit gross primary productivity (GPP) is a possible solution if the key parameter sunlit light use efficiency (ɛsun) could be acquired through remote sensing approaches. Previous studies have shown that the reflectance centered at 531 nm (R531) is very sensitive to variations of ɛsun and the photochemical reflectance index (PRI, the normalized difference index using R531 and R570) can be used as an indicator of ɛsun at the leaf level though little is known about the PRI-ɛsun relationship at the canopy level due to the mixing of sunlit and shaded leaves. In this study, the photochemical reflectance ratio (PRR, defined as the ratio between R531 and R570) is proposed to enable the sunlit-shaded separation of the canopy reflectance observations acquired from a tower based multi-angular platform. The canopy PRR can be expressed as the algebraic sum of sunlit PRR and shaded PRR weighted by the visible portions of the sunlit canopy and the shaded canopy respectively. The visible portions from different angles were simulated using the 4-Scale model and the sunlit (/shaded) PRR was acquired through solving a set of equations describing the canopy PRR obtained from different angles. The relationships between the sunlit PRR (PRRsun) and ɛsun were studied for a white pine stand (TP39) and a sugar maple stand (HA). At both sites, significant correlations between PRRsun and ɛsun were obtained (R2 = 0.57 (TP39), 0.585 (HA), p < 0.001), showing the ability of PRRsun to track the variation of ɛsun. Nevertheless, differences existed in the expressions of the PRRsun-ɛsun relationship between TP39 and HA, a general expression could not be found. Further studies have shown that introducing the normalized difference vegetation index (NDVI) to correct PRRsun (NDVI × PRRsun) largely removed such

  4. Radio lighting based on dynamic chaos generators

    CERN Document Server

    Dmitriev, Alexander; Gerasimov, Mark; Itskov, Vadim

    2016-01-01

    A problem of lighting objects and surfaces with artificial sources of noncoherent microwave radiation with the aim to observe them using radiometric equipment is considered. Transmitters based on dynamic chaos generators are used as sources of noncoherent wideband microwave radiation. An experimental sample of such a device, i.e., a radio lighting lamp based on a chaos microgenerator and its performance are presented.

  5. Simulation of Ship-Track versus Satellite-Sensor Differences in Oceanic Precipitation Using an Island-Based Radar

    Directory of Open Access Journals (Sweden)

    Jörg Burdanowitz

    2017-06-01

    Full Text Available The point-to-area problem strongly complicates the validation of satellite-based precipitation estimates, using surface-based point measurements. We simulate the limited spatial representation of light-to-moderate oceanic precipitation rates along ship tracks with respect to areal passive microwave satellite estimates using data from a subtropical island-based radar. The radar data serves to estimate the discrepancy between point-like and areal precipitation measurements. From the spatial discrepancy, two statistical adjustments are derived so that along-track precipitation ship data better represent areal precipitation estimates from satellite sensors. The first statistical adjustment uses the average duration of a precipitation event as seen along a ship track, and the second adjustment uses the median-normalized along-track precipitation rate. Both statistical adjustments combined reduce the root mean squared error by 0.24 mm h − 1 (55% compared to the unadjusted average track of 60 radar pixels in length corresponding to a typical ship speed of 24–34 km h − 1 depending on track orientation. Beyond along-track averaging, the statistical adjustments represent an important step towards a more accurate validation of precipitation derived from passive microwave satellite sensors using point-like along-track surface precipitation reference data.

  6. Light tracking through ice and water -- Scattering and absorption in heterogeneous media with Photonics

    CERN Document Server

    Lundberg, J; Woschnagg, K; Burgess, T; Adams, J; Hundertmark, S; Desiati, P; Niessen, P

    2007-01-01

    In the field of neutrino astronomy, large volumes of optically transparent matter like glacial ice, lake water, or deep ocean water are used as detector media. Elementary particle interactions are studied using in situ detectors recording time distributions and fluxes of the faint photon fields of Cherenkov radiation generated by ultra-relativistic charged particles, typically muons or electrons. The Photonics software package was developed to determine photon flux and time distributions throughout a volume containing a light source through Monte Carlo simulation. Photons are propagated and time distributions are recorded throughout a cellular grid constituting the simulation volume, and Mie scattering and absorption are realised using wavelength and position dependent parameterisations. The photon tracking results are stored in binary tables for transparent access through ANSI-C and C++ interfaces. For higher-level physics applications, like simulation or reconstruction of particle events, it is then possibl...

  7. An improved fiber tracking algorithm based on fiber assignment using the continuous tracking algorithm and two-tensor model

    Institute of Scientific and Technical Information of China (English)

    Liuhong Zhu; Gang Guo

    2012-01-01

    This study tested an improved fiber tracking algorithm, which was based on fiber assignment using a continuous tracking algorithm and a two-tensor model. Different models and tracking decisions were used by judging the type of estimation of each voxel. This method should solve the cross-track problem. This study included eight healthy subjects, two axonal injury patients and seven demyelinating disease patients. This new algorithm clearly exhibited a difference in nerve fiber direction between axonal injury and demyelinating disease patients and healthy control subjects. Compared with fiber assignment with a continuous tracking algorithm, our novel method can track more and longer nerve fibers, and also can solve the fiber crossing problem.

  8. Learning-Based Tracking of Complex Non-Rigid Motion

    Institute of Scientific and Technical Information of China (English)

    Qiang Wang; Hai-Zhou Ai; Guang-You Xu

    2004-01-01

    This paper describes a novel method for tracking complex non-rigid motions by learning the intrinsic object structure.The approach builds on and extends the studies on non-linear dimensionality reduction for object representation,object dynamics modeling and particle filter style tracking.First,the dimensionality reduction and density estimation algorithm is derived for unsupervised learning of object intrinsic representation,and the obtained non-rigid part of object state reduces even to 2-3 dimensions.Secondly the dynamical model is derived and trained based on this intrinsic representation.Thirdly the learned intrinsic object structure is integrated into a particle filter style tracker.It is shown that this intrinsic object representation has some interesting properties and based on which the newly derived dynamical model makes particle filter style tracker more robust and reliable.Extensive experiments are done on the tracking of challenging non-rigid motions such as fish twisting with selfocclusion,large inter-frame lip motion and facial expressions with global head rotation.Quantitative results are given to make comparisons between the newly proposed tracker and the existing tracker.The proposed method also has the potential to solve other type of tracking problems.

  9. A Robust Vision-based Runway Detection and Tracking Algorithm for Automatic UAV Landing

    KAUST Repository

    Abu Jbara, Khaled F.

    2015-05-01

    This work presents a novel real-time algorithm for runway detection and tracking applied to the automatic takeoff and landing of Unmanned Aerial Vehicles (UAVs). The algorithm is based on a combination of segmentation based region competition and the minimization of a specific energy function to detect and identify the runway edges from streaming video data. The resulting video-based runway position estimates are updated using a Kalman Filter, which can integrate other sensory information such as position and attitude angle estimates to allow a more robust tracking of the runway under turbulence. We illustrate the performance of the proposed lane detection and tracking scheme on various experimental UAV flights conducted by the Saudi Aerospace Research Center. Results show an accurate tracking of the runway edges during the landing phase under various lighting conditions. Also, it suggests that such positional estimates would greatly improve the positional accuracy of the UAV during takeoff and landing phases. The robustness of the proposed algorithm is further validated using Hardware in the Loop simulations with diverse takeoff and landing videos generated using a commercial flight simulator.

  10. A web-based virtual lighting simulator

    Energy Technology Data Exchange (ETDEWEB)

    Papamichael, Konstantinos; Lai, Judy; Fuller, Daniel; Tariq, Tara

    2002-05-06

    This paper is about a web-based ''virtual lighting simulator,'' which is intended to allow architects and lighting designers to quickly assess the effect of key parameters on the daylighting and lighting performance in various space types. The virtual lighting simulator consists of a web-based interface that allows navigation through a large database of images and data, which were generated through parametric lighting simulations. At its current form, the virtual lighting simulator has two main modules, one for daylighting and one for electric lighting. The daylighting module includes images and data for a small office space, varying most key daylighting parameters, such as window size and orientation, glazing type, surface reflectance, sky conditions, time of the year, etc. The electric lighting module includes images and data for five space types (classroom, small office, large open office, warehouse and small retail), varying key lighting parameters, such as the electric lighting system, surface reflectance, dimming/switching, etc. The computed images include perspectives and plans and are displayed in various formats to support qualitative as well as quantitative assessment. The quantitative information is in the form of iso-contour lines superimposed on the images, as well as false color images and statistical information on work plane illuminance. The qualitative information includes images that are adjusted to account for the sensitivity and adaptation of the human eye. The paper also includes a section on the major technical issues and their resolution.

  11. 城市轨道交通高架桥的选型%Selection on Construction Type of City Light-track Traffic High Bridge

    Institute of Scientific and Technical Information of China (English)

    余凤翔

    2001-01-01

    根据上海地铁二号线东西延伸段、莘闵轻轨交通线,西安地铁等工程,探讨了城市轨道交通高架桥在选型上应考虑的因素,并结合具体工程项目,给出了选型的参考性方案。%Based on the east and west extensions section of Shanghai No.2 metro line, Xinmin light track traffic line and Xian metro etc. projects, some factors which should be considered in selection of construction type of city track traffic high bridge were discussed. Reference scheme was given on selection on construction type of high bridge in city track traffic.

  12. AUV-Based Plume Tracking: A Simulation Study

    Directory of Open Access Journals (Sweden)

    Awantha Jayasiri

    2016-01-01

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

  13. Mathematical model for light scanning system based on circular laser

    Institute of Scientific and Technical Information of China (English)

    Peiquan Xu; Shun Yao; Fenggui Lu; Xinhua Tang; Wei Zhang

    2005-01-01

    A novel light scanning system based on circular laser trajectory for welding robot is developed. With the help of image processing technique, intelligent laser welding could be realized. According to laser triangulation algorithm and Scheimpflug condition, mathematical model for circular laser vision is built.This scanning system projects circular laser onto welded seams and recovers the depth of the welded seams,escapes from shortcomings of less information, explains ambiguity and single tracking direction inherent in "spot" or "line" type laser trajectory. Three-dimensional (3D) model for welded seams could be recognized after depth recovery. The imaging error is investigated also.

  14. Object tracking algorithm based on contextual visual saliency

    Science.gov (United States)

    Fu, Bao; Peng, XianRong

    2016-09-01

    As to object tracking, the local context surrounding of the target could provide much effective information for getting a robust tracker. The spatial-temporal context (STC) learning algorithm proposed recently considers the information of the dense context around the target and has achieved a better performance. However STC only used image intensity as the object appearance model. But this appearance model not enough to deal with complicated tracking scenarios. In this paper, we propose a novel object appearance model learning algorithm. Our approach formulates the spatial-temporal relationships between the object of interest and its local context based on a Bayesian framework, which models the statistical correlation between high-level features (Circular-Multi-Block Local Binary Pattern) from the target and its surrounding regions. The tracking problem is posed by computing a visual saliency map, and obtaining the best target location by maximizing an object location likelihood function. Extensive experimental results on public benchmark databases show that our algorithm outperforms the original STC algorithm and other state-of-the-art tracking algorithms.

  15. Triplet based online track finding in the PANDA-STT

    Science.gov (United States)

    Mertens, M. C.; Panda Collaboration

    2014-04-01

    The PANDA-Experiment at the future FAIR facility in Darmstadt will study antiproton-proton collisions in a fixed-target setup with a phase-space cooled antiproton beam with a momentum from 1.5 to 15 GeV/c at a nominal interaction rate of 2 · 107 s-1. The data acquisition of the detectors has to run in a triggerless mode and the physics events of interest are identified by an online event filter. Tracking information is a key input for the event filter to distinguish signal events from background. A variety of tracking algorithms is foreseen to process the different track topologies. The so-called Triplet Finder, which is presented here, is a track finding algorithm based on the central straw tube tracker (STT) of PANDA. The algorithm focuses on mathematical simplicity and robustness to allow an online processing of the incoming detector hits. The algorithm and results of a proof-of-concept implementation are presented.

  16. PARTICLE FILTER BASED VEHICLE TRACKING APPROACH WITH IMPROVED RESAMPLING STAGE

    Directory of Open Access Journals (Sweden)

    Wei Leong Khong

    2014-02-01

    Full Text Available Optical sensors based vehicle tracking can be widely implemented in traffic surveillance and flow control. The vast development of video surveillance infrastructure in recent years has drawn the current research focus towards vehicle tracking using high-end and low cost optical sensors. However, tracking vehicles via such sensors could be challenging due to the high probability of changing vehicle appearance and illumination, besides the occlusion and overlapping incidents. Particle filter has been proven as an approach which can overcome nonlinear and non-Gaussian situations caused by cluttered background and occlusion incidents. Unfortunately, conventional particle filter approach encounters particle degeneracy especially during and after the occlusion. Particle filter with sampling important resampling (SIR is an important step to overcome the drawback of particle filter, but SIR faced the problem of sample impoverishment when heavy particles are statistically selected many times. In this work, genetic algorithm has been proposed to be implemented in the particle filter resampling stage, where the estimated position can converge faster to hit the real position of target vehicle under various occlusion incidents. The experimental results show that the improved particle filter with genetic algorithm resampling method manages to increase the tracking accuracy and meanwhile reduce the particle sample size in the resampling stage.

  17. Method based on the double sideband technique for the dynamic tracking of micrometric particles

    Science.gov (United States)

    Ramirez, Claudio; Lizana, Angel; Iemmi, Claudio; Campos, Juan

    2016-06-01

    Digital holography (DH) methods are of interest in a large number of applications. Recently, the double sideband (DSB) technique was proposed, which is a DH based method that, by using double filtering, provides reconstructed images without distortions and is free of twin images by using an in-line configuration. In this work, we implement a method for the investigation of the mobility of particles based on the DSB technique. Particle holographic images obtained using the DSB method are processed with digital picture recognition methods, allowing us to accurately track the spatial position of particles. The dynamic nature of the method is achieved experimentally by using a spatial light modulator. The suitability of the proposed tracking method is validated by determining the trajectory and velocity described by glass microspheres in movement.

  18. Maximum Power Point Tracking Based on Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Nimrod Vázquez

    2015-01-01

    Full Text Available Solar panels, which have become a good choice, are used to generate and supply electricity in commercial and residential applications. This generated power starts with the solar cells, which have a complex relationship between solar irradiation, temperature, and output power. For this reason a tracking of the maximum power point is required. Traditionally, this has been made by considering just current and voltage conditions at the photovoltaic panel; however, temperature also influences the process. In this paper the voltage, current, and temperature in the PV system are considered to be a part of a sliding surface for the proposed maximum power point tracking; this means a sliding mode controller is applied. Obtained results gave a good dynamic response, as a difference from traditional schemes, which are only based on computational algorithms. A traditional algorithm based on MPPT was added in order to assure a low steady state error.

  19. Tracking target objects orbiting earth using satellite-based telescopes

    Energy Technology Data Exchange (ETDEWEB)

    De Vries, Willem H; Olivier, Scot S; Pertica, Alexander J

    2014-10-14

    A system for tracking objects that are in earth orbit via a constellation or network of satellites having imaging devices is provided. An object tracking system includes a ground controller and, for each satellite in the constellation, an onboard controller. The ground controller receives ephemeris information for a target object and directs that ephemeris information be transmitted to the satellites. Each onboard controller receives ephemeris information for a target object, collects images of the target object based on the expected location of the target object at an expected time, identifies actual locations of the target object from the collected images, and identifies a next expected location at a next expected time based on the identified actual locations of the target object. The onboard controller processes the collected image to identify the actual location of the target object and transmits the actual location information to the ground controller.

  20. Object Detection and Tracking Method of AUV Based on Acoustic Vision

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tie-dong; WAN Lei; ZENG Wen-jing; XU Yu-ru

    2012-01-01

    This paper describes a new framework for object detection and tracking of AUV including underwater acoustic data interpolation,underwater acoustic images segmentation and underwater objects tracking.This framework is applied to the design of vision-based method for AUV based on the forward looking sonar sensor.First,the real-time data flow (underwater acoustic images) is pre-processed to form the whole underwater acoustic image,and the relevant position information of objects is extracted and determined.An improved method of double threshold segmentation is proposed to resolve the problem that the threshold cannot be adjusted adaptively in the traditional method.Second,a representation of region information is created in light of the Gaussian particle filter.The weighted integration strategy combining the area and invariant moment is proposed to perfect the weight of particles and to enhance the tracking robustness.Results obtained on the real acoustic vision platform of AUV during sea trials are displayed and discussed.They show that the proposed method can detect and track the moving objects underwater online,and it is effective and robust.

  1. Object detection and tracking method of AUV based on acoustic vision

    Science.gov (United States)

    Zhang, Tie-dong; Wan, Lei; Zeng, Wen-jing; Xu, Yu-ru

    2012-12-01

    This paper describes a new framework for object detection and tracking of AUV including underwater acoustic data interpolation, underwater acoustic images segmentation and underwater objects tracking. This framework is applied to the design of vision-based method for AUV based on the forward looking sonar sensor. First, the real-time data flow (underwater acoustic images) is pre-processed to form the whole underwater acoustic image, and the relevant position information of objects is extracted and determined. An improved method of double threshold segmentation is proposed to resolve the problem that the threshold cannot be adjusted adaptively in the traditional method. Second, a representation of region information is created in light of the Gaussian particle filter. The weighted integration strategy combining the area and invariant moment is proposed to perfect the weight of particles and to enhance the tracking robustness. Results obtained on the real acoustic vision platform of AUV during sea trials are displayed and discussed. They show that the proposed method can detect and track the moving objects underwater online, and it is effective and robust.

  2. 2D Hand Tracking Based on Flocking with Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Zihong Chen

    2014-02-01

    Full Text Available Hand gesture-based interaction provides a natural and powerful means for human-computer interaction. It is also a good interface for human-robot interaction. However, most of the existing proposals are likely to fail when they meet some skin-coloured objects, especially the face region. In this paper, we present a novel hand tracking method which can track the features of the hand based on the obstacle avoidance flocking behaviour model to overcome skin-coloured distractions. It allows features to be split into two groups under severe distractions and merge later. The experiment results show that our method can track the hand in a cluttered background or when passing the face, while the Flocking of Features (FoF and the Mean Shift Embedded Particle Filter (MSEPF methods may fail. These results suggest that our method has better performance in comparison with the previous methods. It may therefore be helpful to promote the use of the hand gesture-based human-robot interaction method.

  3. Person Tracking System by Fusing Multicues Based on Patches

    Directory of Open Access Journals (Sweden)

    Song Min Jia

    2015-01-01

    Full Text Available A person tracking algorithm by fusing multicues based on patches is proposed to solve the problem of distinguishing person, occlusion, and illumination variations. Kinect is mounted on the robot for providing color images and depth maps. A detector representing a person by using the fusion of multicues based on patches is proposed. The detector divides the person into many patches and then represents each patch by using depth-color histograms and depth-texture histograms. The appearance representation, considering depth, color, and texture information, has powerful discrimination ability to handle the problems of occlusion, illumination changes, and pose variations. Considering the motion of the robot and person, a tracker called motion extended Kalman filter (MEKF is presented to predict the person’s position. The result of the tracker is treated as a candidate sample of the detector, and then the result of the detector is the previous knowledge of the tracker. The detector and tracker supplement each other and improve the tracking performance. To drive the robot towards the given person precisely, a fuzzy based intelligent gear control strategy (FZ-IGS is implemented. Experiments demonstrate that the proposed approach can track a person in a complex environment and have an optimum performance.

  4. Sinusoidal synthesis based adaptive tracking for rotating machinery fault detection

    Science.gov (United States)

    Li, Gang; McDonald, Geoff L.; Zhao, Qing

    2017-01-01

    This paper presents a novel Sinusoidal Synthesis Based Adaptive Tracking (SSBAT) technique for vibration-based rotating machinery fault detection. The proposed SSBAT algorithm is an adaptive time series technique that makes use of both frequency and time domain information of vibration signals. Such information is incorporated in a time varying dynamic model. Signal tracking is then realized by applying adaptive sinusoidal synthesis to the vibration signal. A modified Least-Squares (LS) method is adopted to estimate the model parameters. In addition to tracking, the proposed vibration synthesis model is mainly used as a linear time-varying predictor. The health condition of the rotating machine is monitored by checking the residual between the predicted and measured signal. The SSBAT method takes advantage of the sinusoidal nature of vibration signals and transfers the nonlinear problem into a linear adaptive problem in the time domain based on a state-space realization. It has low computation burden and does not need a priori knowledge of the machine under the no-fault condition which makes the algorithm ideal for on-line fault detection. The method is validated using both numerical simulation and practical application data. Meanwhile, the fault detection results are compared with the commonly adopted autoregressive (AR) and autoregressive Minimum Entropy Deconvolution (ARMED) method to verify the feasibility and performance of the SSBAT method.

  5. 2D Hand Tracking Based on Flocking with Obstacle Avoidance

    Directory of Open Access Journals (Sweden)

    Zihong Chen

    2014-02-01

    Full Text Available Hand gesture-based interaction provides a natural and powerful means for human-computer interaction. It is also a good interface for human-robot interaction. However, most of the existing proposals are likely to fail when they meet some skin-coloured objects, especially the face region. In this paper, we present a novel hand tracking method which can track the features of the hand based on the obstacle avoidance flocking behaviour model to overcome skin-coloured distractions. It allows features to be split into two groups under severe distractions and merge later. The experiment results show that our method can track the hand in a cluttered background or when passing the face, while the Flocking of Features (FoF and the Mean Shift Embedded Particle Filter (MSEPF methods may fail. These results suggest that our method has better performance in comparison with the previous methods. It may therefore be helpful to promote the use of the hand gesture-based human-robot interaction method.

  6. Goniometric characterization of LED based greenhouse lighting

    DEFF Research Database (Denmark)

    Thorseth, Anders; Lindén, Johannes; Corell, Dennis Dan

    2015-01-01

    This paper describes a demonstration of goniospectroradiometry for characterizations of new light emitting diode (LED) based luminaries for enhanced photosynthesis in greenhouses. It highlights the differences between measurement of the traditional high pressure sodium (HPS) luminaries and the LED...

  7. Comparative system identification of flower tracking performance in three hawkmoth species reveals adaptations for dim light vision.

    Science.gov (United States)

    Stöckl, Anna L; Kihlström, Klara; Chandler, Steven; Sponberg, Simon

    2017-04-05

    Flight control in insects is heavily dependent on vision. Thus, in dim light, the decreased reliability of visual signal detection also prompts consequences for insect flight. We have an emerging understanding of the neural mechanisms that different species employ to adapt the visual system to low light. However, much less explored are comparative analyses of how low light affects the flight behaviour of insect species, and the corresponding links between physiological adaptations and behaviour. We investigated whether the flower tracking behaviour of three hawkmoth species with different diel activity patterns revealed luminance-dependent adaptations, using a system identification approach. We found clear luminance-dependent differences in flower tracking in all three species, which were explained by a simple luminance-dependent delay model, which generalized across species. We discuss physiological and anatomical explanations for the variance in tracking responses, which could not be explained by such simple models. Differences between species could not be explained by the simple delay model. However, in several cases, they could be explained through the addition on a second model parameter, a simple scaling term, that captures the responsiveness of each species to flower movements. Thus, we demonstrate here that much of the variance in the luminance-dependent flower tracking responses of hawkmoths with different diel activity patterns can be captured by simple models of neural processing.This article is part of the themed issue 'Vision in dim light'.

  8. Electronic image stabilization system based on global feature tracking

    Institute of Scientific and Technical Information of China (English)

    Zhu Juanjuan; Guo Baolong

    2008-01-01

    A new robust electronic image stabilization system is presented, which involves feature-point, tracking based global motion estimation and Kalman filtering based motion compensation. First, global motion is estimated from the local motions of selected feature points. Considering the local moving objects or the inevitable mismatch,the matching validation, based on the stable relative distance between the points set is proposed, thus maintaining high accuracy and robustness. Next, the global motion parameters are accumulated for correction by Kalman filter-ation. The experimental result illustrates that the proposed system is effective to stabilize translational, rotational,and zooming jitter and robust to local motions.

  9. Ethical Issues In Monitoring And Based Tracking Systems

    Directory of Open Access Journals (Sweden)

    Othman O. Khalifa

    2012-01-01

    Full Text Available Monitoring and based tracking systems use a variety of technologies to record and monitor the activities of humans.  This can increase the risks to the privacy and security of individuals. The amount of information gathered about individuals is growing through the proliferation of surveillance cameras, sensors; microchips and Radio Frequency Identification RFID tags embedded in devices and products. Advances in electronic technologies allow companies and government agencies to store and process large amounts of information about individuals. The Internet provides the ultimate copier device, making this information easily available to millions. This paper highlights the ethical issues emerging with the new technologies in the monitoring and base tracking system. New regulations should be proposed to protect the individual privacy.ABSTRAK: Pemantauan dan sistem berasaskan pengesanan menggunakan pelbagai teknologi untuk merakam dan memantau aktiviti manusia. Ini boleh meningkatkan risiko dari segi privasi dan keselamatan individu. Jumlah maklumat yang dikumpulkan tentang individu berkembang melalui proliferasi pengawasan kamera, sensor; mikrocip dan tag frekuensi radio yang diletakkan di dalam peranti dan produk. Kemajuan dalam teknologi elektronik membolehkan syarikat-syarikat dan agensi-agensi kerajaan menyimpan dan memproses sejumlah besar maklumat mengenai individu. Internet menyediakan peranti salinan utama, menjadikan maklumat ini didapati dengan mudah. Kajian ini memaparkan isu-isu etika yang baru muncul dengan teknologi baru dalam pemantauan dan sistem berasaskan pengesanan. Peraturan baru perlu dicadangkan untuk melindungi privasi individu.Keywords: Privacy Implications, Tracking Systems, EthicalIssue, RFID

  10. Analytical phase-tracking-based strain estimation for ultrasound elasticity.

    Science.gov (United States)

    Yuan, Lili; Pedersen, Peder C

    2015-01-01

    A new strain estimator for quasi-static elastography is presented, based on tracking of the analytical signal phase as a function of the external force. Two implementations are introduced: zero-phase search with moving window (SMW) and zero-phase band tracking using connected component labeling (CCL). Low analytical signal amplitude caused by local destructive interference is associated with large error in the phase trajectories, and amplitude thresholding can thus be used to terminate the phase tracking along a particular path. Interpolation is then applied to estimate displacement in the eliminated path. The paper describes first a mathematical analysis based on 1-D multi-scatter modeling, followed by a statistical study of the displacement and strain error. Simulation and experiment with an inhomogeneous phantom indicate that SMW and CCL are capable of reliably estimating tissue displacement and strain over a larger range of deformation than standard timedomain cross-correlation (SCC). Results also show that SMW is roughly 40 times faster than SCC with comparable or even better accuracy. CCL is slower than SMW, but more noise robust. Simulation assessment at compression level 3% and 6% with SNR 20 dB demonstrates average strain error for SMW and CCL of 10%, whereas SCC achieves 18%.

  11. Vision-based method for tracking meat cuts in slaughterhouses

    DEFF Research Database (Denmark)

    Larsen, Anders Boesen Lindbo; Hviid, Marchen Sonja; Engbo Jørgensen, Mikkel

    2014-01-01

    Meat traceability is important for linking process and quality parameters from the individual meat cuts back to the production data from the farmer that produced the animal. Current tracking systems rely on physical tagging, which is too intrusive for individual meat cuts in a slaughterhouse...... environment. In this article, we demonstrate a computer vision system for recognizing meat cuts at different points along a slaughterhouse production line. More specifically, we show that 211 pig loins can be identified correctly between two photo sessions. The pig loins undergo various perturbation scenarios...... (hanging, rough treatment and incorrect trimming) and our method is able to handle these perturbations gracefully. This study shows that the suggested vision-based approach to tracking is a promising alternative to the more intrusive methods currently available....

  12. Study on tracking technology of the moving object based on computer vision

    Science.gov (United States)

    Xu, Ranran; Xu, Zhenying; Li, Boquan

    2010-10-01

    The tracking technology of the moving object has been an active topic of the visual tracking system. In this paper, the tracking algorithms are classified into four classes: correlation-based methods, boundary-based methods, model-based methods and multifunctional methods. Based on the analysis of the advantages and disadvantages of all these algorithms, a new tracking algorithm, integrating SSDA and advanced Camshift algorithm, is put forward here.

  13. A New Inertial Aid Method for High Dynamic Compass Signal Tracking Based on a Nonlinear Tracking Differentiator

    Directory of Open Access Journals (Sweden)

    Wenqi Wu

    2012-06-01

    Full Text Available In Compass/INS integrated navigation systems, feedback inertial navigation solutions to baseband tracking loops may eliminate receiver dynamic effects, and effectively improve the tracking accuracy and sensitivity. In the conventional inertially-aided tracking loop, the satellite-receiver line-of-sight velocity is used directly to adjust local carrier frequency. However, if the inertial solution drifts, the phase tracking error will be enlarged. By using Kalman filter based carrier phase tracking loop, this paper introduces a new inertial aid method, in which the line-of-sight jerk obtained from inertial acceleration by a nonlinear tracking differentiator is used to adjust relevant parameters of the Kalman filter’s process noise matrix. Validation is achieved through high dynamic Compass B3 signal with line-of-sight jerk of 10 g/s collected by a GNSS simulator. Experimental results indicate that the new inertial aid method proposed in this paper is free of the impact of the receiver dynamic and inertial errors. Therefore, when the integrated navigation system is starting or re-tracking after losing lock, the inertial error is absent from the navigation solution correction that induces large drift, and the new aid method proposed in this paper can track highly dynamic signals.

  14. A new inertial aid method for high dynamic Compass signal tracking based on a nonlinear tracking differentiator.

    Science.gov (United States)

    Guo, Yao; Wu, Wenqi; Tang, Kanghua

    2012-01-01

    In Compass/INS integrated navigation systems, feedback inertial navigation solutions to baseband tracking loops may eliminate receiver dynamic effects, and effectively improve the tracking accuracy and sensitivity. In the conventional inertially-aided tracking loop, the satellite-receiver line-of-sight velocity is used directly to adjust local carrier frequency. However, if the inertial solution drifts, the phase tracking error will be enlarged. By using Kalman filter based carrier phase tracking loop, this paper introduces a new inertial aid method, in which the line-of-sight jerk obtained from inertial acceleration by a nonlinear tracking differentiator is used to adjust relevant parameters of the Kalman filter's process noise matrix. Validation is achieved through high dynamic Compass B3 signal with line-of-sight jerk of 10 g/s collected by a GNSS simulator. Experimental results indicate that the new inertial aid method proposed in this paper is free of the impact of the receiver dynamic and inertial errors. Therefore, when the integrated navigation system is starting or re-tracking after losing lock, the inertial error is absent from the navigation solution correction that induces large drift, and the new aid method proposed in this paper can track highly dynamic signals.

  15. Track finding processor in the DTBX based CMS barrel muon trigger

    CERN Document Server

    Kluge, A

    1996-01-01

    We present the design and simulation of the track finding processor in the DTBX ( Drift Tube with Bunch Crossing Identification) based CMS barrel muon trigger system. The processor searches for muon tracks originating from the interaction region by joining the track segments provided by the mean timer processors of the drift chambers to track strings. It assigns transverse momenta to the reconstructed tracks using the tracks' bending angle. High speed is achieved by performing the track reconstruction fully in parallel. In this contribution the algorithms, implementation and simulation results are presented.

  16. Track Detection in Railway Sidings Based on MEMS Gyroscope Sensors

    Directory of Open Access Journals (Sweden)

    Miguel A. López

    2012-11-01

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

  17. Track detection in railway sidings based on MEMS gyroscope sensors.

    Science.gov (United States)

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

    2012-11-23

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

  18. Track Detection in Railway Sidings Based on MEMS Gyroscope Sensors

    Science.gov (United States)

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

    2012-01-01

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

  19. GPS based Advanced Vehicle Tracking and Vehicle Control System

    Directory of Open Access Journals (Sweden)

    Mashood Mukhtar

    2015-02-01

    Full Text Available Security systems and navigators have always been a necessity of human‟s life. The developments of advanced electronics have brought revolutionary changes in these fields. In this paper, we will present a vehicle tracking system that employs a GPS module and a GSM modem to find the location of a vehicle and offers a range of control features. To complete the design successfully, a GPS unit, two relays, a GSM Modem and two MCU units are used. There are five features introduced in the project. The aim of this project is to remotely track a vehicle‟s location, remotely switch ON and OFF the vehicle‟s ignition system and remotely lock and unlock the doors of the vehicle. An SMS message is sent to the tracking system and the system responds to the users request by performing appropriate actions. Short text messages are assigned to each of these features. A webpage is specifically designed to view the vehicle‟s location on Google maps. By using relay based control concept introduced in this paper, number of control features such as turning heater on/off, radio on/off etc. can be implemented in the same fashion.

  20. Visual tracking based on extreme learning machine and sparse representation.

    Science.gov (United States)

    Wang, Baoxian; Tang, Linbo; Yang, Jinglin; Zhao, Baojun; Wang, Shuigen

    2015-10-22

    The existing sparse representation-based visual trackers mostly suffer from both being time consuming and having poor robustness problems. To address these issues, a novel tracking method is presented via combining sparse representation and an emerging learning technique, namely extreme learning machine (ELM). Specifically, visual tracking can be divided into two consecutive processes. Firstly, ELM is utilized to find the optimal separate hyperplane between the target observations and background ones. Thus, the trained ELM classification function is able to remove most of the candidate samples related to background contents efficiently, thereby reducing the total computational cost of the following sparse representation. Secondly, to further combine ELM and sparse representation, the resultant confidence values (i.e., probabilities to be a target) of samples on the ELM classification function are used to construct a new manifold learning constraint term of the sparse representation framework, which tends to achieve robuster results. Moreover, the accelerated proximal gradient method is used for deriving the optimal solution (in matrix form) of the constrained sparse tracking model. Additionally, the matrix form solution allows the candidate samples to be calculated in parallel, thereby leading to a higher efficiency. Experiments demonstrate the effectiveness of the proposed tracker.

  1. Visual Tracking Based on Extreme Learning Machine and Sparse Representation

    Directory of Open Access Journals (Sweden)

    Baoxian Wang

    2015-10-01

    Full Text Available The existing sparse representation-based visual trackers mostly suffer from both being time consuming and having poor robustness problems. To address these issues, a novel tracking method is presented via combining sparse representation and an emerging learning technique, namely extreme learning machine (ELM. Specifically, visual tracking can be divided into two consecutive processes. Firstly, ELM is utilized to find the optimal separate hyperplane between the target observations and background ones. Thus, the trained ELM classification function is able to remove most of the candidate samples related to background contents efficiently, thereby reducing the total computational cost of the following sparse representation. Secondly, to further combine ELM and sparse representation, the resultant confidence values (i.e., probabilities to be a target of samples on the ELM classification function are used to construct a new manifold learning constraint term of the sparse representation framework, which tends to achieve robuster results. Moreover, the accelerated proximal gradient method is used for deriving the optimal solution (in matrix form of the constrained sparse tracking model. Additionally, the matrix form solution allows the candidate samples to be calculated in parallel, thereby leading to a higher efficiency. Experiments demonstrate the effectiveness of the proposed tracker.

  2. Discharge light and carbonization distribution characteristics at XLPE-silicon rubber interface with micro-cavity in tracking failure test

    Science.gov (United States)

    Gu, L.; Li, S.; Wang, S. B.; Lei, S. L.; Liu, S. X.

    2011-12-01

    Installation of cross-linked polyethylene (XLPE) cable joint possibly introduces defects into the XLPE-silicon rubber interface, such as micro-cavity and micro-wire. Those defects greatly decrease the interfacial breakdown strength and endanger the stability of power system. However, the traditional method only measures the breakdown strength, which alone is limited and can not provide detailed information to more clearly understand the dielectric performance and tracking failure mechanism. This paper investigated the effect of micro-cavity on tracking failure by analyzing the distribution characteristics of discharge light and carbonization. Interfaces with those defects were setup by pressing together a slice of XLPE and a slice of transparent silicon rubber. A 50 Hz AC voltage was applied on a pair of flat-round electrodes sandwiched at the interface with their insulation distance of 5 mm until tracking failure occurred. The evolution of both discharge light and carbonization at the interface from discharge to the failure was recorded with a video recorder and then their channel width was analyzed with image processing method. Obtained results show that micro-cavity at an XLPE-silicon rubber interface strengthens the transportation of charge and easily leads to interfacial discharge and tracking failure. The distribution of discharge light and carbonization at the interface with micro-wire proves this.

  3. Track initiation of bearings-only tracking based on ant navigation concept

    Science.gov (United States)

    Zhu, Jihong; Xu, Benlian; Wang, Zhiquan

    2010-11-01

    A novel heuristic track initiation method is developed for the bearing-only multi-sensor-multi-target tracking system, in which each target is assumed to move with a straight line. The key idea of the proposed method is derived from the ant navigation concept in its foraging life, which differs from the traditional ant colony optimization algorithm, and it utilizes the concept of path integration and visual landmarks in ants' navigation toolkit to find the exact positions of each target. Numerous numerical simulations are conducted and the effectiveness of the proposed track initiation method is verified according to the probability of correct track initiation.

  4. Ellipse Fitting Based Approach for Extended Object Tracking

    Directory of Open Access Journals (Sweden)

    Borui Li

    2014-01-01

    Full Text Available With the increase of sensors’ resolution, traditional object tracking technology, which ignores object’s physical extension, gradually becomes inappropriate. Extended object tracking (EOT technology is able to obtain more information about the object through jointly estimating both centroid’s dynamic state and physical extension of the object. Random matrix based approach is a promising method for EOT. It uses ellipse/ellipsoid to describe the physical extension of the object. In order to reduce the physical extension estimation error when object maneuvers, the relationship between ellipse/ellipsoid and symmetrical positive definite matrix is analyzed at first. On this basis, ellipse/ellipsoid fitting based approach (EFA for EOT is proposed based on the measurement model and centroid’s dynamic model of random matrix based EOT approach. Simulation results show that EFA is effective. The physical extension estimation error of EFA is lower than those of random matrix based approaches when object maneuvers. Besides, the estimation error of centroid’s dynamic state of EFA is also lower.

  5. GPU-based quasi-real-time Track Recognition in Imaging Devices: from raw Data to Particle Tracks

    CERN Document Server

    Bozza, Cristiano; De Sio, Chiara; Stellacci, Simona Maria

    2015-01-01

    Nuclear emulsions as tracking devices have been used by recent experiments thanks to fast automatic microscopes for emulsion readout. Automatic systems are evolving towards GPU-based solutions. Real-time imaging is needed to drive the motion of the microscope axes and 3D track recognition occurs quasi-online in local GPU clusters. The algorithms implemented in the Quick Scanning System are sketched. Most of them are very general and might turn out useful for other detector

  6. Markerless rat head motion tracking using structured light for brain PET imaging of unrestrained awake small animals

    Science.gov (United States)

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

    2017-03-01

    Preclinical positron emission tomography (PET) imaging in small animals is generally performed under anesthesia to immobilize the animal during scanning. More recently, for rat brain PET studies, methods to perform scans of unrestrained awake rats are being developed in order to avoid the unwanted effects of anesthesia on the brain response. Here, we investigate the use of a projected structure stereo camera to track the motion of the rat head during the PET scan. The motion information is then used to correct the PET data. The stereo camera calculates a 3D point cloud representation of the scene and the tracking is performed by point cloud matching using the iterative closest point algorithm. The main advantage of the proposed motion tracking is that no intervention, e.g. for marker attachment, is needed. A manually moved microDerenzo phantom experiment and 3 awake rat [18F]FDG experiments were performed to evaluate the proposed tracking method. The tracking accuracy was 0.33 mm rms. After motion correction image reconstruction, the microDerenzo phantom was recovered albeit with some loss of resolution. The reconstructed FWHM of the 2.5 and 3 mm rods increased with 0.94 and 0.51 mm respectively in comparison with the motion-free case. In the rat experiments, the average tracking success rate was 64.7%. The correlation of relative brain regional [18F]FDG uptake between the anesthesia and awake scan reconstructions was increased from on average 0.291 (not significant) before correction to 0.909 (p  <  0.0001) after motion correction. Markerless motion tracking using structured light can be successfully used for tracking of the rat head for motion correction in awake rat PET scans.

  7. A New Track Reconstruction Algorithm suitable for Parallel Processing based on Hit Triplets and Broken Lines

    CERN Document Server

    Schöning, Andre

    2016-01-01

    Track reconstruction in high track multiplicity environments at current and future high rate particle physics experiments is a big challenge and very time consuming. The search for track seeds and the fitting of track candidates are usually the most time consuming steps in the track reconstruction. Here, a new and fast track reconstruction method based on hit triplets is proposed which exploits a three-dimensional fit model including multiple scattering and hit uncertainties from the very start, including the search for track seeds. The hit triplet based reconstruction method assumes a homogeneous magnetic field which allows to give an analytical solutions for the triplet fit result. This method is highly parallelizable, needs fewer operations than other standard track reconstruction methods and is therefore ideal for the implementation on parallel computing architectures. The proposed track reconstruction algorithm has been studied in the context of the Mu3e-experiment and a typical LHC experiment.

  8. A New Track Reconstruction Algorithm suitable for Parallel Processing based on Hit Triplets and Broken Lines

    Science.gov (United States)

    Schöning, André

    2016-11-01

    Track reconstruction in high track multiplicity environments at current and future high rate particle physics experiments is a big challenge and very time consuming. The search for track seeds and the fitting of track candidates are usually the most time consuming steps in the track reconstruction. Here, a new and fast track reconstruction method based on hit triplets is proposed which exploits a three-dimensional fit model including multiple scattering and hit uncertainties from the very start, including the search for track seeds. The hit triplet based reconstruction method assumes a homogeneous magnetic field which allows to give an analytical solutions for the triplet fit result. This method is highly parallelizable, needs fewer operations than other standard track reconstruction methods and is therefore ideal for the implementation on parallel computing architectures. The proposed track reconstruction algorithm has been studied in the context of the Mu3e-experiment and a typical LHC experiment.

  9. High precision dual-axis tracking solar wireless charging system based on the four quadrant photoelectric sensor

    Science.gov (United States)

    Liu, Zhilong; Wang, Biao; Tong, Weichao

    2015-08-01

    This paper designs a solar automatic tracking wireless charging system based on the four quadrant photoelectric sensor. The system track the sun's rays automatically in real time to received the maximum energy and wireless charging to the load through electromagnetic coupling. Four quadrant photoelectric sensor responsive to the solar spectrum, the system could get the current azimuth and elevation angle of the light by calculating the solar energy incident on the sensor profile. System driver the solar panels by the biaxial movement mechanism to rotate and tilt movement until the battery plate and light perpendicular to each other. Maximize the use of solar energy, and does not require external power supply to achieve energy self-sufficiency. Solar energy can be collected for portable devices and load wireless charging by close electromagnetic field coupling. Experimental data show that: Four quadrant photoelectric sensor more sensitive to light angle measurement. when track positioning solar light, Azimuth deviation is less than 0.8°, Elevation angle deviation is less than 0.6°. Use efficiency of a conventional solar cell is only 10% -20%.The system uses a Four quadrant dual-axis tracking to raise the utilization rate of 25% -35%.Wireless charging electromagnetic coupling efficiency reached 60%.

  10. Track-to-Track Association Based on Structural Similarity in the Presence of Sensor Biases

    Directory of Open Access Journals (Sweden)

    Hongyan Zhu

    2014-01-01

    Full Text Available The paper addresses the problem of track-to-track association in the presence of sensor biases. In some challenging scenarios, it may be infeasible to implement bias estimation and compensation in time due to the computational intractability or weak observability about sensor biases. In this paper, we introduce the structural feature for each local track, which describes the spatial relationship with its neighboring targets. Although the absolute coordinates of local tracks from the same target are severely different in the presence of sensor biases, their structural features may be similar. As a result, instead of using the absolute kinematic states only, we employee the structural similarity to define the association cost. When there are missed detections, the structural similarity between local tracks is evaluated by solving another 2D assignment subproblem. Simulation results demonstrated the power of the proposed approach.

  11. Data-Base Software For Tracking Technological Developments

    Science.gov (United States)

    Aliberti, James A.; Wright, Simon; Monteith, Steve K.

    1996-01-01

    Technology Tracking System (TechTracS) computer program developed for use in storing and retrieving information on technology and related patent information developed under auspices of NASA Headquarters and NASA's field centers. Contents of data base include multiple scanned still images and quick-time movies as well as text. TechTracS includes word-processing, report-editing, chart-and-graph-editing, and search-editing subprograms. Extensive keyword searching capabilities enable rapid location of technologies, innovators, and companies. System performs routine functions automatically and serves multiple users.

  12. Space debris tracking based on fuzzy running Gaussian average adaptive particle filter track-before-detect algorithm

    Science.gov (United States)

    Torteeka, Peerapong; Gao, Peng-Qi; Shen, Ming; Guo, Xiao-Zhang; Yang, Da-Tao; Yu, Huan-Huan; Zhou, Wei-Ping; Zhao, You

    2017-02-01

    Although tracking with a passive optical telescope is a powerful technique for space debris observation, it is limited by its sensitivity to dynamic background noise. Traditionally, in the field of astronomy, static background subtraction based on a median image technique has been used to extract moving space objects prior to the tracking operation, as this is computationally efficient. The main disadvantage of this technique is that it is not robust to variable illumination conditions. In this article, we propose an approach for tracking small and dim space debris in the context of a dynamic background via one of the optical telescopes that is part of the space surveillance network project, named the Asia-Pacific ground-based Optical Space Observation System or APOSOS. The approach combines a fuzzy running Gaussian average for robust moving-object extraction with dim-target tracking using a particle-filter-based track-before-detect method. The performance of the proposed algorithm is experimentally evaluated, and the results show that the scheme achieves a satisfactory level of accuracy for space debris tracking.

  13. Maximum Power Point Tracking of Photovoltaic power Generation System Based on Fuzzy Approximation of Operating Point Voltage with Radiation Intensity

    Directory of Open Access Journals (Sweden)

    H. Ijadi

    2012-09-01

    Full Text Available In this paper, a method to track the maximum power of solar panels based on fuzzy logic is presented. The proposed method is based on the relationship between radiation intensity and the voltage of maximum power operating point. With this relationship, at any time by measuring the light intensity, voltage can be calculated at the maximum power point by using fuzzy approximation function. In order to verify the proposed method, simulation results are presented.

  14. Vision-based vehicle detection and tracking algorithm design

    Science.gov (United States)

    Hwang, Junyeon; Huh, Kunsoo; Lee, Donghwi

    2009-12-01

    The vision-based vehicle detection in front of an ego-vehicle is regarded as promising for driver assistance as well as for autonomous vehicle guidance. The feasibility of vehicle detection in a passenger car requires accurate and robust sensing performance. A multivehicle detection system based on stereo vision has been developed for better accuracy and robustness. This system utilizes morphological filter, feature detector, template matching, and epipolar constraint techniques in order to detect the corresponding pairs of vehicles. After the initial detection, the system executes the tracking algorithm for the vehicles. The proposed system can detect front vehicles such as the leading vehicle and side-lane vehicles. The position parameters of the vehicles located in front are obtained based on the detection information. The proposed vehicle detection system is implemented on a passenger car, and its performance is verified experimentally.

  15. Mode-Tracking Based Stationary-Point Optimization

    CERN Document Server

    Bergeler, Maike; Reiher, Markus

    2014-01-01

    In this work, we present a transition-state optimization protocol based on the Mode-Tracking algorithm [J. Chem. Phys. 118 (2003) 1634]. By calculating only the eigenvector of interest instead of diagonalizing the full Hessian matrix and performing an eigenvector following search based on the selectively calculated vector, we can efficiently optimize transition-state structures. The initial guess structures and eigenvectors are either chosen from a linear interpolation between the reactant and product structures, from a nudged-elastic band search, from a constrained-optimization scan, or from the minimum-energy structures. Alternatively, initial guess vectors based on chemical intuition may be defined. We then iteratively refine the selected vectors by the Davidson subspace iteration technique. This procedure accelerates finding transition states for large molecules of a few hundred atoms. It is also beneficial in cases where the starting structure is very different from the transition-state structure or wher...

  16. A novel body frame based approach to aerospacecraft attitude tracking.

    Science.gov (United States)

    Ma, Carlos; Chen, Michael Z Q; Lam, James; Cheung, Kie Chung

    2017-09-01

    In the common practice of designing an attitude tracker for an aerospacecraft, one transforms the Newton-Euler rotation equations to obtain the dynamic equations of some chosen inertial frame based attitude metrics, such as Euler angles and unit quaternions. A Lyapunov approach is then used to design a controller which ensures asymptotic convergence of the attitude to the desired orientation. Although this design methodology is pretty standard, it usually involves singularity-prone coordinate transformations which complicates the analysis process and controller design. A new, singularity free error feedback method is proposed in the paper to provide simple and intuitive stability analysis and controller synthesis. This new body frame based method utilizes the concept of Euleraxis and angles to generate the smallest error angles from a body frame perspective, without coordinate transformations. Global tracking convergence is illustrated with the use of a feedback linearizing PD tracker, a sliding mode controller, and a model reference adaptive controller. Experimental results are also obtained on a quadrotor platform with unknown system parameters and disturbances, using a boundary layer approximated sliding mode controller, a PIDD controller, and a unit sliding mode controller. Significant tracking quality is attained. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Digital Image-Based Automatic Tracking Capability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — OPTRA proposes to develop an Automated Optical Tracking Capability tailored to NASA's network of optical tracking stations at the Kennedy Space Center. This will be...

  18. A new track inspection car based on a laser camera system

    Institute of Scientific and Technical Information of China (English)

    Shengwei Ren; Shiping Gu; Guiyang Xu; Zhan Gao; Qibo Feng

    2011-01-01

    @@ We develop and build a new type of inspection car.A beam that is not rigidly connected to the train axle boxes and can absorb the vibration and impact caused by the high speed train is used, and a laser-camera measurement system based on the machine vision method is adopted.This method projects structural light onto the track and measures gauge and longitudinal irregularity.The measurement principle and model are discussed.Through numerous practical experiments, the rebuilt car is found to considerably eliminate the measurement errors caused by vibration and impact, thereby increasing measurement stability under high speeds.This new kind of inspection cars have been used in several Chinese administration bureaus.%We develop and build a new type of inspection car. A beam that is not rigidly connected to the train axle boxes and can absorb the vibration and impact caused by the high speed train is used, and a laser-camera measurement system based on the machine vision method is adopted. This method projects structural light onto the track and measures gauge and longitudinal irregularity. The measurement principle and model are discussed. Through numerous practical experiments, the rebuilt car is found to considerably eliminate the measurement errors caused by vibration and impact, thereby increasing measurement stability under high speeds. This new kind of inspection cars have been used in several Chinese administration bureaus.

  19. Choice of tracks, microtubules and/or actin filaments for chloroplast photo-movement is differentially controlled by phytochrome and a blue light receptor.

    Science.gov (United States)

    Sato, Y; Wada, M; Kadota, A

    2001-01-01

    Light induced chloroplast movement has been studied as a model system for photoreception and actin microfilament (MF)-based intracellular motilities in plants. Chloroplast photo-accumulation and -avoidance movement is mediated by phytochrome as well as blue light (BL) receptor in the moss Physcomitrella patens. Here we report the discovery of an involvement of a microtubule (MT)-based system in addition to an MF-based system in photorelocation of chloroplasts in this moss. In the dark, MTs provided tracks for rapid movement of chloroplasts in a longitudinal direction and MFs contributed the tracks for slow movement in any direction. We found that phytochrome responses utilized only the MT-based system, while BL responses had an alternative way of moving, either along MTs or MFs. MT-based systems were mediated by both photoreceptors, but chloroplasts showed movements with different velocity and pattern between them. No apparent difference in the behavior of chloroplast movement between the accumulation and avoidance movement was detected in phytochrome responses or BL responses, except for the direction of the movement. The results presented here demonstrate that chloroplasts use both MTs and MFs for motility and that phytochrome and a BL receptor control directional photo-movement of chloroplasts through the differential regulation of these motile systems.

  20. Assessing Light Pollution in China Based on Nighttime Light Imagery

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2017-02-01

    Full Text Available Rapid urbanization and economic development inevitably lead to light pollution, which has become a universal environmental issue. In order to reveal the spatiotemporal patterns and evolvement rules of light pollution in China, images from 1992 to 2012 were selected from the Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS and systematically corrected to ensure consistency. Furthermore, we employed a linear regression trend method and nighttime light index method to demonstrate China’s light pollution characteristics across national, regional, and provincial scales, respectively. We found that: (1 China’s light pollution expanded significantly in provincial capital cities over the past 21 years and hot-spots of light pollution were located in the eastern coastal region. The Yangtze River Delta, Pearl River Delta, and Beijing–Tianjin–Hebei regions have formed light pollution stretch areas; (2 China’s light pollution was mainly focused in areas of north China (NC and east China (EC, which, together, accounted for over 50% of the light pollution for the whole country. The fastest growth of light pollution was observed in northwest China (NWC, followed by southwest China (SWC. The growth rates of east China (EC, central China (CC, and northeast China (NEC were stable, while those of north China (NC and south China (SC declined; (3 Light pollution at the provincial scale was mainly located in the Shandong, Guangdong, and Hebei provinces, whereas the fastest growth of light pollution was in Tibet and Hainan. However, light pollution levels in the developed provinces (Hong Kong, Macao, Shanghai, and Tianjin were higher than those of the undeveloped provinces. Similarly, the light pollution heterogeneities of Taiwan, Beijing, and Shanghai were higher than those of undeveloped western provinces.

  1. Discharge light and carbonization distribution characteristics at XLPE-silicon rubber interface with silicon-grease in tracking failure test

    Science.gov (United States)

    Gu, Liang; Liu, W.; Lei, S. L.; Wang, S. B.; Deng, Y. Y.

    2011-06-01

    Imaging processing method was adopted to investigate the effect of silicon grease on tracking failure of the XLPEsilicon rubber interface by analyzing the distribution characteristics of discharge light and carbonization at the interface. Three interfaces were set up by pressing together a slice of XLPE and a slice of transparent silicon rubber. One filled silicon grease and the other partly filled the grease. As comparison, the third one filled on grease. High voltage (AC 50 Hz) was applied on a pair of flat-round electrodes sandwiched at the interface with their insulation distance of 5 mm. When the test voltage was raised to a certain value, discharge occurred and discharge light appeared and carbonization accumulated at the interface. The discharge light from discharge to the failure and the carbonization after the failure was recorded with a digital video recorder and then the images were analyzed with image processing method. Obtained results show that silicon grease at the interface weakens the transportation of charge and enhances the interfacial breakdown strength. However, interfacial discharge and tracking failure easily occur once discharge appears. Image processing method is helpful to understand the tracking failure process and mechanism of XLPE cable joint.

  2. Area Variation Based Color Snake Algorithm for Moving Object Tracking

    Institute of Scientific and Technical Information of China (English)

    Shoum-ik ROYCHOUDHURY; Young-joon HAN

    2010-01-01

    A snake algorithm has been known that it has a strong point in extracting the exact contour of an object.But it is apt to be influenced by scattered edges around the control points.Since the shape of a moving object in 2D image changes a lot due ta its rotation and translation in the 3D space,the conventional algorithm that takes into account slowly moving objects cannot provide an appropriate solution.To utilize the advantages of the snake algrithm while minimizing the drawbacks,this paper proposes the area variation based color snake algorithm for moving object tracking.The proposed algorithm includes a new energy term which is used for preserving the shape of an object between two consecutive inages.The proposed one can also segment precisely interesting objects on complex image since it is based on color information.Experiment results show that the proposed algorithm is very effective in various environments.

  3. 3-D model-based tracking for UAV indoor localization.

    Science.gov (United States)

    Teulière, Céline; Marchand, Eric; Eck, Laurent

    2015-05-01

    This paper proposes a novel model-based tracking approach for 3-D localization. One main difficulty of standard model-based approach lies in the presence of low-level ambiguities between different edges. In this paper, given a 3-D model of the edges of the environment, we derive a multiple hypotheses tracker which retrieves the potential poses of the camera from the observations in the image. We also show how these candidate poses can be integrated into a particle filtering framework to guide the particle set toward the peaks of the distribution. Motivated by the UAV indoor localization problem where GPS signal is not available, we validate the algorithm on real image sequences from UAV flights.

  4. Kalman Filter Based Tracking in an Video Surveillance System

    Directory of Open Access Journals (Sweden)

    SULIMAN, C.

    2010-05-01

    Full Text Available In this paper we have developed a Matlab/Simulink based model for monitoring a contact in a video surveillance sequence. For the segmentation process and corect identification of a contact in a surveillance video, we have used the Horn-Schunk optical flow algorithm. The position and the behavior of the correctly detected contact were monitored with the help of the traditional Kalman filter. After that we have compared the results obtained from the optical flow method with the ones obtained from the Kalman filter, and we show the correct functionality of the Kalman filter based tracking. The tests were performed using video data taken with the help of a fix camera. The tested algorithm has shown promising results.

  5. Color-based tracking of plasma dust particles

    Energy Technology Data Exchange (ETDEWEB)

    Villamayor, Michelle Marie S., E-mail: mvillamayor@nip.upd.edu.ph; Soriano, Maricor N.; Ramos, Henry J. [National Institute of Physics, University of the Philippines, Diliman, Quezon City 1101 (Philippines); Kato, Shuichi; Wada, Motoi [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2014-02-15

    Color-based tracking to observe agglomeration of deposited particles inside a compact planar magnetron during plasma discharge was done by creating high dynamic range (HDR) images of photos captured by a Pentax K10D digital camera. Carbon erosion and redeposition was also monitored using the technique. The HDR images were subjected to a chromaticity-based constraint discoloration inside the plasma chamber indicating film formation or carbon redeposition. Results show that dust deposition occurs first near the evacuation pumps due to the pressure gradient and then accumulates at the positively charged walls of the chamber. This method can be applied to monitor dust formation during dusty plasma experiments without major modification of plasma devices, useful especially for large fusion reactors.

  6. Hierarchical online appearance-based tracking for 3D head pose, eyebrows, lips, eyelids, and irises

    NARCIS (Netherlands)

    Orozco, Javier; Rudovic, Ognjen; Gonzalez Garcia, Jordi; Pantic, Maja

    2013-01-01

    In this paper, we propose an On-line Appearance-Based Tracker (OABT) for simultaneous tracking of 3D head pose, lips, eyebrows, eyelids and irises in monocular video sequences. In contrast to previously proposed tracking approaches, which deal with face and gaze tracking separately, our OABT can als

  7. Ultrasonography-based motion tracking for MRgFUS

    Science.gov (United States)

    Jenne, Jürgen W.; Tretbar, Steffen H.; Hewener, Holger J.; Speicher, Daniel; Barthscherer, Tobias; Sarti, Cristina; Bongers, André; Schwaab, Julia; Günther, Matthias

    2017-03-01

    Non-invasive treatment of moving organs like liver and kidney with high intensity focused ultrasound (HIFU/FUS) is challenging. The highly precise HIFU ablation requires real-time knowledge of tumor position with mm precision. The aim of this work was to build up a magnetic resonance imaging compatible tracking device using diagnostic ultrasound imaging for MR guided FUS (MRgFUS). The hardware of the developed US-tracking system comprises the ultrasound beam former with a screen directly placed in front of the MR-magnet, a linear and a special ultrasound tracking probe. The tracking probe (2x64 element phased array) can acquire two perpendicularly oriented US-image planes for quasi 3D tracking. The US-data are sent to a workstation in the console room of the MRI scanner which controls the whole tracking device. The tracking software (Sonoplan II) analyzes the ultrasound image stream and calculates the actual position of pre-defined contours. Beside the 2D-translation, the tracking algorithm analyzes the rotation as well as the 2D scaling of the contour. The developed US-tracking system proved MR-compatibility in 1.5 and 3 T MR-systems and enabled simultaneous MR- and US-imaging and motion tracking. In the next step, the tracking system will be combined with an MRgFUS unit.

  8. Big Crunch-based omnidirectional light concentrators

    CERN Document Server

    Smolyaninov, Igor I

    2014-01-01

    Omnidirectional light concentration remains an unsolved problem despite such important practical applications as design of efficient mobile photovoltaic cells. Optical black hole designs developed recently offer partial solution to this problem. However, even these solutions are not truly omnidirectional since they do not exhibit a horizon, and at large enough incidence angles light may be trapped into quasi-stationary orbits around such imperfect optical black holes. Here we propose and realize experimentally another gravity-inspired design of a broadband omnidirectional light concentrator based on the cosmological Big Crunch solutions. By mimicking the Big Crunch spacetime via corresponding effective optical metric we make sure that every photon world line terminates in a single point.

  9. Tracking 3D Moving Objects Based on GPS/IMU Navigation Solution, Laser Scanner Point Cloud and GIS Data

    Directory of Open Access Journals (Sweden)

    Siavash Hosseinyalamdary

    2015-07-01

    Full Text Available Monitoring vehicular road traffic is a key component of any autonomous driving platform. Detecting moving objects, and tracking them, is crucial to navigating around objects and predicting their locations and trajectories. Laser sensors provide an excellent observation of the area around vehicles, but the point cloud of objects may be noisy, occluded, and prone to different errors. Consequently, object tracking is an open problem, especially for low-quality point clouds. This paper describes a pipeline to integrate various sensor data and prior information, such as a Geospatial Information System (GIS map, to segment and track moving objects in a scene. We show that even a low-quality GIS map, such as OpenStreetMap (OSM, can improve the tracking accuracy, as well as decrease processing time. A bank of Kalman filters is used to track moving objects in a scene. In addition, we apply non-holonomic constraint to provide a better orientation estimation of moving objects. The results show that moving objects can be correctly detected, and accurately tracked, over time, based on modest quality Light Detection And Ranging (LiDAR data, a coarse GIS map, and a fairly accurate Global Positioning System (GPS and Inertial Measurement Unit (IMU navigation solution.

  10. Auto Target Tracking Robot Design Based on Smartphone

    Directory of Open Access Journals (Sweden)

    Shuen De Wu

    2016-03-01

    Full Text Available This paper describes a robot tracking control design based on a smartphone using a commercial microprocessor. The system hardware consists of four major parts: an Android smartphone with an embedded camera, a Microchip microprocessor, a motor driver circuit and an Attacknid robot. First, an image of the surrounding environment is captured by the high definition camera embedded in the smartphone. The target is then recognized from the image using an algorithm developed in Android OS and OpenCV library. Third, motion control and laser activation strategies are achieved using the proposed algorithm implemented in Java. Fourth, the motion commands are delivered to the microchip processor through a USB interface. Finally, the processor produces a pulse width modulation (PWM voltage to control the robot’s motion and activate the laser diode according commands sent from the smart phone. Experimental results demonstrate the feasibility of this proposed architecture.

  11. Hybrid Structure Based Tracking and Consensus for Multiple Motors

    Directory of Open Access Journals (Sweden)

    Changfan Zhang

    2014-01-01

    system; however, the obtained stable system may encounter a large enough disturbance that can destroy the synchronization. Focusing on this challenging technological problem about how to receive more robust synchronization during steady-state process, this paper first proposes a state-dependent-switching based leader-following control approach, in which synchronization includes two parts, one associated with tracking control for all members, and the other one associated with consensus maintained among followers in the case that one follower loses synchronization with the leader during steady-state motion. By employing the algebra graph theory, matrix theory, and Lyapunov analysis, the convergence and stability of the given multimotor system are proved. Finally, simulation examples are presented to demonstrate the effectiveness and robustness of the theoretical results.

  12. Transient stability improvement by nonlinear controllers based on tracking

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, Juan M. [Centro de Investigacion y Estudios Avanzados, Guadalajara, Mexico. Av. Cientifica 1145. Col. El Bajio. Zapopan, Jal. 45015 (Mexico); Arroyave, Felipe Valencia; Correa Gutierrez, Rosa Elvira [Universidad Nacional de Colombia, Sede Medellin. Facultad de Minas, Escuela de Mecatronica (Colombia)

    2011-02-15

    This paper deals with the control problem in multi-machine electric power systems, which represent complex great scale nonlinear systems. Thus, the controller design is a challenging problem. These systems are subjected to different perturbations, such as short circuits, connection and/or disconnection of loads, lines, or generators. Then, the utilization of controllers which guarantee good performance under those perturbations is required in order to provide electrical energy to the loads with admissible stability margins. The proposed controllers are based on a systematic strategy, which calculate nonlinear controllers for generating units in a power plant, both for voltage and velocity regulation. The formulation allows designing controllers in a multi-machine power system without intricate calculations. Results on a power system of the open research indicate the proposition's suitability. The problem is formulated as a tracking problem. The designed controllers may be implemented in any electric power system. (author)

  13. Design and Implementation of PLC-Based Automatic Sun tracking System for Parabolic Trough Solar Concentrator

    Directory of Open Access Journals (Sweden)

    Wang Jinping

    2016-01-01

    Full Text Available A sun-tracking system for parabolic trough solar concentrators (PTCs is a control system used to orient the concentrator toward the sun always, so that the maximum energy can be collected. The work presented here is a design and development of PLC based sun tracking control system for PTC. Sun tracking control system consists of a Programmable Logic Controller (PLC and a single axis hydraulic drives tracking control system. Hydraulic drives and the necessary tracking angle algorithm have been designed and developed to perform the technical tasks. A PLC unit was employed to control and monitor the mechanical movement of the PTC and to collect and store data related to the tracking angle of PTC. It is found that the tracking error of the system is less than 0.6°. Field experience shows that tracking algorithm act stable and reliable and suit for PTCs.

  14. A Target Tracking Method Based on Dynamic Salient Features

    Directory of Open Access Journals (Sweden)

    H. C. Ke

    2015-06-01

    Full Text Available Given that dealing with blocking of traditional target tracking algorithm is not enough, a target tracking method fused into dynamic salient features is proposed by simulating human visual mechanism to ensure accuracy and efficiency. First, the salient features of the bottom layer image, such as color, intensity, orientation, and motion, are extracted. These features are considered feature vectors fused into target tracking algorithm. An improved target tracking algorithm is proposed because local regional histogram of target is influenced by the background pixels of the background region. Experiment results show that the proposed target tracking algorithm is more accurate than the traditional tracking algorithm in dealing with blocking, thereby meeting the needs of complex scenes.

  15. Speckle tracking in a phantom and feature-based tracking in liver in the presence of respiratory motion using 4D ultrasound

    Science.gov (United States)

    Harris, Emma J.; Miller, Naomi R.; Bamber, Jeffrey C.; Symonds-Tayler, J. Richard N.; Evans, Philip M.

    2010-06-01

    We have evaluated a 4D ultrasound-based motion tracking system developed for tracking of abdominal organs during therapy. Tracking accuracy and precision were determined using a tissue-mimicking phantom, by comparing tracked motion with known 3D sinusoidal motion. The feasibility of tracking 3D liver motion in vivo was evaluated by acquiring 4D ultrasound data from four healthy volunteers. For two of these volunteers, data were also acquired whilst simultaneously measuring breath flow using a spirometer. Hepatic blood vessels, tracked off-line using manual tracking, were used as a reference to assess, in vivo, two types of automated tracking algorithm: incremental (from one volume to the next) and non-incremental (from the first volume to each subsequent volume). For phantom-based experiments, accuracy and precision (RMS error and SD) were found to be 0.78 mm and 0.54 mm, respectively. For in vivo measurements, mean absolute distance and standard deviation of the difference between automatically and manually tracked displacements were less than 1.7 mm and 1 mm respectively in all directions (left-right, anterior-posterior and superior-inferior). In vivo non-incremental tracking gave the best agreement. In both phantom and in vivo experiments, tracking performance was poorest for the elevational component of 3D motion. Good agreement between automatically and manually tracked displacements indicates that 4D ultrasound-based motion tracking has potential for image guidance applications in therapy.

  16. CRISPR-Based Typing and Next-Generation Tracking Technologies.

    Science.gov (United States)

    Barrangou, Rodolphe; Dudley, Edward G

    2016-01-01

    Bacteria occur ubiquitously in nature and are broadly relevant throughout the food supply chain, with diverse and variable tolerance levels depending on their origin, biological role, and impact on the quality and safety of the product as well as on the health of the consumer. With increasing knowledge of and accessibility to the microbial composition of our environments, food supply, and host-associated microbiota, our understanding of and appreciation for the ratio of beneficial to undesirable bacteria are rapidly evolving. Therefore, there is a need for tools and technologies that allow definite, accurate, and high-resolution identification and typing of various groups of bacteria that include beneficial microbes such as starter cultures and probiotics, innocuous commensals, and undesirable pathogens and spoilage organisms. During the transition from the current molecular biology-based PFGE (pulsed-field gel electrophoresis) gold standard to the increasingly accessible omics-level whole-genome sequencing (WGS) N-gen standard, high-resolution technologies such as CRISPR-based genotyping constitute practical and powerful alternatives that provide valuable insights into genome microevolution and evolutionary trajectories. Indeed, several studies have shown potential for CRISPR-based typing of industrial starter cultures, health-promoting probiotic strains, animal commensal species, and problematic pathogens. Emerging CRISPR-based typing methods open new avenues for high-resolution typing of a broad range of bacteria and constitute a practical means for rapid tracking of a diversity of food-associated microbes.

  17. Space Object Tracking Method Based on a Snake Model

    Science.gov (United States)

    Zhan-wei, Xu; Xin, Wang

    2016-04-01

    In this paper, aiming at the problem of unstable tracking of low-orbit variable and bright space objects, adopting an active contour model, a kind of improved GVF (Gradient Vector Flow) - Snake algorithm is proposed to realize the real-time search of the real object contour on the CCD image. Combined with the Kalman filter for prediction, a new adaptive tracking method is proposed for space objects. Experiments show that this method can overcome the tracking error caused by the fixed window, and improve the tracking robustness.

  18. Track segment association algorithm based on statistical binary thresholds

    Directory of Open Access Journals (Sweden)

    Qi Lin

    2015-05-01

    Full Text Available The classical Track Segment Association (TSA algorithm suffers from low accuracy and is impractical to use in concentrated targets, branching, and cross-tracking environment. Thus, a new statistical binary track segment association algorithm is proposed. The new algorithm is more appropriate as it increases the sample size for the χ2 distribution threshold detection. Simulation results show that in air cross tracking and for ballistic targets, the global correct association rate and the average correct association rate of the proposed algorithm are remarkably improved, which proves the good performance of the proposed algorithm.

  19. An Online Learning-based Framework for Tracking

    CERN Document Server

    Chaudhuri, Kamalika; Hsu, Daniel

    2012-01-01

    We study the tracking problem, namely, estimating the hidden state of an object over time, from unreliable and noisy measurements. The standard framework for the tracking problem is the generative framework, which is the basis of solutions such as the Bayesian algorithm and its approximation, the particle filters. However, these solutions can be very sensitive to model mismatches. In this paper, motivated by online learning, we introduce a new framework for tracking. We provide an efficient tracking algorithm for this framework. We provide experimental results comparing our algorithm to the Bayesian algorithm on simulated data. Our experiments show that when there are slight model mismatches, our algorithm outperforms the Bayesian algorithm.

  20. Plasma-based EUV light source

    Science.gov (United States)

    Shumlak, Uri; Golingo, Raymond; Nelson, Brian A.

    2010-11-02

    Various mechanisms are provided relating to plasma-based light source that may be used for lithography as well as other applications. For example, a device is disclosed for producing extreme ultraviolet (EUV) light based on a sheared plasma flow. The device can produce a plasma pinch that can last several orders of magnitude longer than what is typically sustained in a Z-pinch, thus enabling the device to provide more power output than what has been hitherto predicted in theory or attained in practice. Such power output may be used in a lithography system for manufacturing integrated circuits, enabling the use of EUV wavelengths on the order of about 13.5 nm. Lastly, the process of manufacturing such a plasma pinch is discussed, where the process includes providing a sheared flow of plasma in order to stabilize it for long periods of time.

  1. Near-wall nanovelocimetry based on Total Internal Reflection Fluorescence with continuous tracking

    CERN Document Server

    Li, Zhenzhen; Lee, Choongyeop; Monti, Fabrice; Yonger, Marc; Chollet, Benjamin; Bresson, Bruno; Tran, Yvette; Tabeling, Patrick

    2014-01-01

    The goal of this work is to make progress in the domain of near-wall velocimetry. The technique we use is based on the tracking of nanoparticles in an evanescent field, close to a wall, a technique called TIRF (Total Internal Reflection Fluorescence)-based velocimetry. At variance with the methods developed in the literature, we permanently keep track of the light emitted by each particle during the time the measurements of their positions ('altitudes') and speeds are performed. By performing the Langevin simulation, we quantified effect of biases such as Brownian motion, heterogeneities induced by the walls, statistical biases, photo bleaching, polydispersivity and limited depth of field. Using this method, we obtained slip length on hydrophilic surfaces of 1$ \\pm $5 nm for sucrose solution, and 9$ \\pm $10 nm for water; On hydrophobic surface, 32$ \\pm $5 nm for sucrose solution, and 55$ \\pm $9 nm for water. The errors (based on 95% confidence intervals) are significantly smaller than the state-of-the-art, bu...

  2. A Solar Automatic Tracking System that Generates Power for Lighting Greenhouses

    Directory of Open Access Journals (Sweden)

    Qi-Xun Zhang

    2015-07-01

    Full Text Available In this study we design and test a novel solar tracking generation system. Moreover, we show that this system could be successfully used as an advanced solar power source to generate power in greenhouses. The system was developed after taking into consideration the geography, climate, and other environmental factors of northeast China. The experimental design of this study included the following steps: (i the novel solar tracking generation system was measured, and its performance was analyzed; (ii the system configuration and operation principles were evaluated; (iii the performance of this power generation system and the solar irradiance were measured according to local time and conditions; (iv the main factors affecting system performance were analyzed; and (v the amount of power generated by the solar tracking system was compared with the power generated by fixed solar panels. The experimental results indicated that compared to the power generated by fixed solar panels, the solar tracking system generated about 20% to 25% more power. In addition, the performance of this novel power generating system was found to be closely associated with solar irradiance. Therefore, the solar tracking system provides a new approach to power generation in greenhouses.

  3. L0 Confirmation with fast, Tsa based tracking in the T-stations

    CERN Document Server

    Albrecht, J; Terrier, H

    2007-01-01

    A fast tracking algorithm to confirm the high $p_T$ L0 trigger objects with tracks from the T-stations is presented. The L0 trigger candidate is used to define a search window to a potential track. Using this, a seeded track search is performed. The track finding algorithm is based on the \\textit{TsaSeeding} algorithm~\\cite{bib:Tsa}. The efficiency to confirm a true L0 trigger signal is around 96\\%, the momentum can be measured up to $\\Delta p/p$=3\\%.

  4. Hypersonic Vehicle Tracking Based on Improved Current Statistical Model

    Directory of Open Access Journals (Sweden)

    He Guangjun

    2013-11-01

    Full Text Available A new method of tracking the near space hypersonic vehicle is put forward. According to hypersonic vehicles’ characteristics, we improved current statistical model through online identification of the maneuvering frequency. A Monte Carlo simulation is used to analyze the performance of the method. The results show that the improved method exhibits very good tracking performance in comparison with the old method.

  5. Wave measurement based on light refraction

    Institute of Scientific and Technical Information of China (English)

    SUN Hequan; QIU Dahong; SHEN Yongming; WANG Yongxue

    2004-01-01

    Some authors have developed a few methods of measuring wave slopes based on light refraction, including the measurement method via the distribution of light intensity or color under water. A new method based on light refraction is specified for the measurement of wave surface elevation in wave flume via imaging technology. A plane painted with black and white stripes is put on the flume floor as an indication plane, which can be arranged easily and cheaply. Compared with the previous methods, the present method is less sensitive to the noise and nonlinear effects of optical process, which can be taken as a digital method. The CCD camera is fixed above the flume with its optical axis arranged vertically to grab the images of stripes modulated by the wave surface. The modulated value can be calculated from the Hilbert transform, and then the wave surface elevation can be obtained. The algorithm and experimental procedure are specified in detail, and some experimental results are provided to show the validity of the present method.

  6. Model Based Design of Video Tracking Based on MATLAB/Simulink and DSP

    Directory of Open Access Journals (Sweden)

    Chachou Mohamed Yacine

    2014-05-01

    Full Text Available The implementation of digital image processing on electronic boards is a current problem. In this study, we present a Model-Based Design of video tracking based on Matlab/Simulink and DSP. The implementation on DSP, of multi-objects detection and tracking algorithms of two kinds of applications inside and outside, is obtained by using automatic code generation that is code composer studio. The transmission and reception of data is realized by a network connection via Ethernet port between DSP and PC. This allows us, in the future, to extend the number of DSP working in parallel and their IP addresses would be generated by a DHCP server.

  7. New light field camera based on physical based rendering tracing

    Science.gov (United States)

    Chung, Ming-Han; Chang, Shan-Ching; Lee, Chih-Kung

    2014-03-01

    Even though light field technology was first invented more than 50 years ago, it did not gain popularity due to the limitation imposed by the computation technology. With the rapid advancement of computer technology over the last decade, the limitation has been uplifted and the light field technology quickly returns to the spotlight of the research stage. In this paper, PBRT (Physical Based Rendering Tracing) was introduced to overcome the limitation of using traditional optical simulation approach to study the light field camera technology. More specifically, traditional optical simulation approach can only present light energy distribution but typically lack the capability to present the pictures in realistic scenes. By using PBRT, which was developed to create virtual scenes, 4D light field information was obtained to conduct initial data analysis and calculation. This PBRT approach was also used to explore the light field data calculation potential in creating realistic photos. Furthermore, we integrated the optical experimental measurement results with PBRT in order to place the real measurement results into the virtually created scenes. In other words, our approach provided us with a way to establish a link of virtual scene with the real measurement results. Several images developed based on the above-mentioned approaches were analyzed and discussed to verify the pros and cons of the newly developed PBRT based light field camera technology. It will be shown that this newly developed light field camera approach can circumvent the loss of spatial resolution associated with adopting a micro-lens array in front of the image sensors. Detailed operational constraint, performance metrics, computation resources needed, etc. associated with this newly developed light field camera technique were presented in detail.

  8. Thermal light ghost imaging based on morphology

    Science.gov (United States)

    Chen, Zhipeng; Shi, Jianhong; Zeng, Guihua

    2016-12-01

    The quality of thermal light ghost imaging could be degraded by undersampling noise. This kind of noise is generated because of finite sampling, which could reduce the signal-to-noise ratio (SNR) of ghost imaging and submerge object information. In order to reduce the undersampling noise, we propose a thermal light ghost imaging scheme based on the morphology (GIM). In this scheme, the average size of the undersampling noise can be obtained by computing the second-order correlation function of the ghost imaging system. According to the average size of the undersampling noise, the corresponding structure element can be designed and used in the morphological filter; then, the GIM reconstructed image can be obtained. The experiment results show that the peak signal-to-noise ratio of the GIM reconstructed image can increased by 80% than that of conventional ghost imaging for the same number of measurements.

  9. Three-dimensional Speckle Tracking Echocardiography in Light Chain Cardiac Amyloidosis: Examination of Left and Right Ventricular Myocardial Mechanics Parameters.

    Science.gov (United States)

    Urbano-Moral, Jose Angel; Gangadharamurthy, Dakshin; Comenzo, Raymond L; Pandian, Natesa G; Patel, Ayan R

    2015-08-01

    The study of myocardial mechanics has a potential role in the detection of cardiac involvement in patients with amyloidosis. This study aimed to characterize 3-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics in light chain amyloidosis and examine their relationship with brain natriuretic peptide. In patients with light chain amyloidosis, left ventricular longitudinal and circumferential strain (n=40), and right ventricular longitudinal strain and radial displacement (n=26) were obtained by 3-dimensional-speckle tracking echocardiography. Brain natriuretic peptide levels were determined. All myocardial mechanics measurements showed differences when compared by brain natriuretic peptide level tertiles. Left and right ventricular longitudinal strain were highly correlated (r=0.95, P<.001). Left ventricular longitudinal and circumferential strain were reduced in patients with cardiac involvement (-9±4 vs -16±2; P<.001, and -24±6 vs -29±4; P=.01, respectively), with the most prominent impairment at the basal segments. Right ventricular longitudinal strain and radial displacement were diminished in patients with cardiac involvement (-9±3 vs -17±3; P<.001, and 2.7±0.8 vs 3.8±0.3; P=.002). On multivariate analysis, left ventricular longitudinal strain was associated with the presence of cardiac involvement (odds ratio = 1.6; 95% confidence interval, 1.04 to 2.37; P=.03) independent of the presence of brain natriuretic peptide and troponin I criteria for cardiac amyloidosis. Three-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics are increasingly altered as brain natriuretic peptide increases in light chain amyloidosis. There appears to be a strong association between left ventricular longitudinal strain and cardiac involvement, beyond biomarkers such as brain natriuretic peptide and troponin I. Copyright © 2015 Sociedad Española de Cardiología. Published by

  10. A universal, easy-to-apply light-quality index based on natural light spectrum resemblance

    Science.gov (United States)

    Jou, Jwo-Huei; Chou, Kun-Yi; Yang, Fu-Chin; Agrawal, Abhishek; Chen, Sun-Zen; Tseng, Jing-Ru; Lin, Ching-Chiao; Chen, Po-Wei; Wong, Ken-Tsung; Chi, Yun

    2014-05-01

    Light-quality is extremely crucial for any light source to be used for illumination. However, a proper light-quality index is still missing although numerous electricity-driven lighting measures have been introduced since past 150 yr. We present in this communication a universal and easy-to-apply index for quantifying the quality of any given lighting source, which is based on direct comparison of its lumen spectrum with the natural light counterpart having the same color temperature. A general principle for creating high quality pseudo-natural light is accordingly derived. By using organic light-emitting diode technology, for example, daylight-style emission with a 96% natural light resemblance is obtained as a high number of organic emitters with diffused colors spanning throughout the entire visible range are employed. The same principle can be extended to other lighting technology such as light-emitting diode to generate natural light-style emission.

  11. Vision-Based Finger Detection, Tracking, and Event Identification Techniques for Multi-Touch Sensing and Display Systems

    Directory of Open Access Journals (Sweden)

    Yang-Lang Chang

    2011-07-01

    Full Text Available This study presents efficient vision-based finger detection, tracking, and event identification techniques and a low-cost hardware framework for multi-touch sensing and display applications. The proposed approach uses a fast bright-blob segmentation process based on automatic multilevel histogram thresholding to extract the pixels of touch blobs obtained from scattered infrared lights captured by a video camera. The advantage of this automatic multilevel thresholding approach is its robustness and adaptability when dealing with various ambient lighting conditions and spurious infrared noises. To extract the connected components of these touch blobs, a connected-component analysis procedure is applied to the bright pixels acquired by the previous stage. After extracting the touch blobs from each of the captured image frames, a blob tracking and event recognition process analyzes the spatial and temporal information of these touch blobs from consecutive frames to determine the possible touch events and actions performed by users. This process also refines the detection results and corrects for errors and occlusions caused by noise and errors during the blob extraction process. The proposed blob tracking and touch event recognition process includes two phases. First, the phase of blob tracking associates the motion correspondence of blobs in succeeding frames by analyzing their spatial and temporal features. The touch event recognition process can identify meaningful touch events based on the motion information of touch blobs, such as finger moving, rotating, pressing, hovering, and clicking actions. Experimental results demonstrate that the proposed vision-based finger detection, tracking, and event identification system is feasible and effective for multi-touch sensing applications in various operational environments and conditions.

  12. Beam-based model of broad-band impedance of the Diamond Light Source

    Science.gov (United States)

    Smaluk, Victor; Martin, Ian; Fielder, Richard; Bartolini, Riccardo

    2015-06-01

    In an electron storage ring, the interaction between a single-bunch beam and a vacuum chamber impedance affects the beam parameters, which can be measured rather precisely. So we can develop beam-based numerical models of longitudinal and transverse impedances. At the Diamond Light Source (DLS) to get the model parameters, a set of measured data has been used including current-dependent shift of betatron tunes and synchronous phase, chromatic damping rates, and bunch lengthening. A matlab code for multiparticle tracking has been developed. The tracking results and analytical estimations are quite consistent with the measured data. Since Diamond has the shortest natural bunch length among all light sources in standard operation, the studies of collective effects with short bunches are relevant to many facilities including next generation of light sources.

  13. Chaos Analysis of Discharge Current Based on Tracking Test of Phenolic Resin

    Institute of Scientific and Technical Information of China (English)

    DU Boxue; ZHENG Xiaolei; DONG Dianshuai

    2009-01-01

    In tracking test,discharge is a complicated process and comparative tracking index(CTI)has wide variation.To evaluate tracking resistance,the chaos analysis of discharge current is presented based on the tracking test ofphenolic resin in accordance with IEC601 12.According to the characteristics of statistical self-similarity and complexity of discharge current,the largest Lyapunov exponent is calculated,and the 2-dimensional attractor ofdischarge current is reconstructed.Moreover,the attractors of discharge current and recurrence plots of different discharge states are reconstructed.The results indicate that the chaos attractors have different characteristics in evolutionary tracks,the topological structure and grain direction of recurrence plots show significant differences.The chaos attractor can describe the tracking process,the recurrence plot can identify the tracking state clearly,while its arithmetic is simple.

  14. Optical flow based Kalman filter for body joint prediction and tracking using HOG-LBP matching

    Science.gov (United States)

    Nair, Binu M.; Kendricks, Kimberley D.; Asari, Vijayan K.; Tuttle, Ronald F.

    2014-03-01

    We propose a real-time novel framework for tracking specific joints in the human body on low resolution imagery using optical flow based Kalman tracker without the need of a depth sensor. Body joint tracking is necessary for a variety of surveillance based applications such as recognizing gait signatures of individuals, identifying the motion patterns associated with a particular action and the corresponding interactions with objects in the scene to classify a certain activity. The proposed framework consists of two stages; the initialization stage and the tracking stage. In the initialization stage, the joints to be tracked are either manually marked or automatically obtained from other joint detection algorithms in the first few frames within a window of interest and appropriate image descriptions of each joint are computed. We employ the use of a well-known image coding scheme known as the Local Binary Patterns (LBP) to represent the joint local region where this image coding removes the variance to non-uniform lighting conditions as well as enhances the underlying edges and corner. The image descriptions of the joint region would then include a histogram computed from the LBP-coded ROI and a HOG (Histogram of Oriented Gradients) descriptor to represent the edge information. Next the tracking stage can be divided into two phases: Optical flow based detection of joints in corresponding frames of the sequence and prediction /correction phases of Kalman tracker with respect to the joint coordinates. Lucas Kanade optical flow is used to locate the individual joints in consecutive frames of the video based on their location in the previous frame. But more often, mismatches can occur due to the rotation of the joint region and the rotation variance of the optical flow matching technique. The mismatch is then determined by comparing the joint region descriptors using Chi-squared metric between a pair of frames and depending on this statistic, either the prediction

  15. Laser-Based Pedestrian Tracking in Outdoor Environments by Multiple Mobile Robots

    Directory of Open Access Journals (Sweden)

    Masafumi Hashimoto

    2012-10-01

    Full Text Available This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures.

  16. Laser-based pedestrian tracking in outdoor environments by multiple mobile robots.

    Science.gov (United States)

    Ozaki, Masataka; Kakimuma, Kei; Hashimoto, Masafumi; Takahashi, Kazuhiko

    2012-10-29

    This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN)-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI) method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS) and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures.

  17. Forecasting Urban Expansion Based on Night Lights

    Science.gov (United States)

    Stathakis, D.

    2016-06-01

    Forecasting urban expansion models are a very powerful tool in the hands of urban planners in order to anticipate and mitigate future urbanization pressures. In this paper, a linear regression forecasting urban expansion model is implemented based on the annual composite night lights time series available from National Oceanic and Atmospheric Administration (NOAA). The product known as 'stable lights' is used in particular, after it has been corrected with a standard intercalibration process to reduce artificial year-to-year fluctuations as much as possible. Forecasting is done for ten years after the end of the time series. Because the method is spatially explicit the predicted expansion trends are relatively accurately mapped. Two metrics are used to validate the process. The first one is the year-to-year Sum of Lights (SoL) variation. The second is the year-to-year image correlation coefficient. Overall it is evident that the method is able to provide an insight on future urbanization pressures in order to be taken into account in planning. The trends are quantified in a clear spatial manner.

  18. Preceding Vehicle Detection and Tracking Adaptive to Illumination Variation in Night Traffic Scenes Based on Relevance Analysis

    Directory of Open Access Journals (Sweden)

    Junbin Guo

    2014-08-01

    Full Text Available Preceding vehicle detection and tracking at nighttime are challenging problems due to the disturbance of other extraneous illuminant sources coexisting with the vehicle lights. To improve the detection accuracy and robustness of vehicle detection, a novel method for vehicle detection and tracking at nighttime is proposed in this paper. The characteristics of taillights in the gray level are applied to determine the lower boundary of the threshold for taillights segmentation, and the optimal threshold for taillight segmentation is calculated using the OTSU algorithm between the lower boundary and the highest grayscale of the region of interest. The candidate taillight pairs are extracted based on the similarity between left and right taillights, and the non-vehicle taillight pairs are removed based on the relevance analysis of vehicle location between frames. To reduce the false negative rate of vehicle detection, a vehicle tracking method based on taillights estimation is applied. The taillight spot candidate is sought in the region predicted by Kalman filtering, and the disturbed taillight is estimated based on the symmetry and location of the other taillight of the same vehicle. Vehicle tracking is completed after estimating its location according to the two taillight spots. The results of experiments on a vehicle platform indicate that the proposed method could detect vehicles quickly, correctly and robustly in the actual traffic environments with illumination variation.

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

    Directory of Open Access Journals (Sweden)

    Piotr Stawicki

    2017-04-01

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

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

    Science.gov (United States)

    Stawicki, Piotr; Gembler, Felix; Rezeika, Aya; Volosyak, Ivan

    2017-04-05

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

  1. D Tracking Based Augmented Reality for Cultural Heritage Data Management

    Science.gov (United States)

    Battini, C.; Landi, G.

    2015-02-01

    The development of contactless documentation techniques is allowing researchers to collect high volumes of three-dimensional data in a short time but with high levels of accuracy. The digitalisation of cultural heritage opens up the possibility of using image processing and analysis, and computer graphics techniques, to preserve this heritage for future generations; augmenting it with additional information or with new possibilities for its enjoyment and use. The collection of precise datasets about cultural heritage status is crucial for its interpretation, its conservation and during the restoration processes. The application of digital-imaging solutions for various feature extraction, image data-analysis techniques, and three-dimensional reconstruction of ancient artworks, allows the creation of multidimensional models that can incorporate information coming from heterogeneous data sets, research results and historical sources. Real objects can be scanned and reconstructed virtually, with high levels of data accuracy and resolution. Real-time visualisation software and hardware is rapidly evolving and complex three-dimensional models can be interactively visualised and explored on applications developed for mobile devices. This paper will show how a 3D reconstruction of an object, with multiple layers of information, can be stored and visualised through a mobile application that will allow interaction with a physical object for its study and analysis, using 3D Tracking based Augmented Reality techniques.

  2. Rover-based visual target tracking validation and mission infusion

    Science.gov (United States)

    Kim, Won S.; Steele, Robert D.; Ansar, Adnan I.; Ali, Khaled; Nesnas, Issa

    2005-01-01

    The Mars Exploration Rovers (MER'03), Spirit and Opportunity, represent the state of the art in rover operations on Mars. This paper presents validation experiments of different visual tracking algorithms using the rover's navigation camera.

  3. Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2008-01-01

    An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...

  4. A Data Warehouse Solution for Analyzing RFID-Based Baggage Tracking Data

    DEFF Research Database (Denmark)

    Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

    2013-01-01

    spatio-temporal Radio Frequency Identification (RFID) baggage tracking data. Analysis of this data can yield interesting results on baggage flow, the causes of baggage mishandling, and the parties responsible for the mishandling(airline, airport, handler,...), which can ultimately lead to improved...... with the appropriate tracking data from the data sources. The presented concepts are generalizable to other types of multi-site indoor tracking systems based on Bluetooth and RFID. The system has been tested with large amount of real-world RFID-based baggage tracking data from a major industry initiative...

  5. Real-time vehicle detection and tracking in video based on faster R-CNN

    Science.gov (United States)

    Zhang, Yongjie; Wang, Jian; Yang, Xin

    2017-08-01

    Vehicle detection and tracking is a significant part in auxiliary vehicle driving system. Using the traditional detection method based on image information has encountered enormous difficulties, especially in complex background. To solve this problem, a detection method based on deep learning, Faster R-CNN, which has very high detection accuracy and flexibility, is introduced. An algorithm of target tracking with the combination of Camshift and Kalman filter is proposed for vehicle tracking. The computation time of Faster R-CNN cannot achieve realtime detection. We use multi-thread technique to detect and track vehicle by parallel computation for real-time application.

  6. Tracking and Classification of In-Air Hand Gesture Based on Thermal Guided Joint Filter

    Science.gov (United States)

    Kim, Seongwan; Ban, Yuseok; Lee, Sangyoun

    2017-01-01

    The research on hand gestures has attracted many image processing-related studies, as it intuitively conveys the intention of a human as it pertains to motional meaning. Various sensors have been used to exploit the advantages of different modalities for the extraction of important information conveyed by the hand gesture of a user. Although many works have focused on learning the benefits of thermal information from thermal cameras, most have focused on face recognition or human body detection, rather than hand gesture recognition. Additionally, the majority of the works that take advantage of multiple modalities (e.g., the combination of a thermal sensor and a visual sensor), usually adopting simple fusion approaches between the two modalities. As both thermal sensors and visual sensors have their own shortcomings and strengths, we propose a novel joint filter-based hand gesture recognition method to simultaneously exploit the strengths and compensate the shortcomings of each. Our study is motivated by the investigation of the mutual supplementation between thermal and visual information in low feature level for the consistent representation of a hand in the presence of varying lighting conditions. Accordingly, our proposed method leverages the thermal sensor’s stability against luminance and the visual sensors textural detail, while complementing the low resolution and halo effect of thermal sensors and the weakness against illumination of visual sensors. A conventional region tracking method and a deep convolutional neural network have been leveraged to track the trajectory of a hand gesture and to recognize the hand gesture, respectively. Our experimental results show stability in recognizing a hand gesture against varying lighting conditions based on the contribution of the joint kernels of spatial adjacency and thermal range similarity. PMID:28106716

  7. Tracking and Classification of In-Air Hand Gesture Based on Thermal Guided Joint Filter.

    Science.gov (United States)

    Kim, Seongwan; Ban, Yuseok; Lee, Sangyoun

    2017-01-17

    The research on hand gestures has attracted many image processing-related studies, as it intuitively conveys the intention of a human as it pertains to motional meaning. Various sensors have been used to exploit the advantages of different modalities for the extraction of important information conveyed by the hand gesture of a user. Although many works have focused on learning the benefits of thermal information from thermal cameras, most have focused on face recognition or human body detection, rather than hand gesture recognition. Additionally, the majority of the works that take advantage of multiple modalities (e.g., the combination of a thermal sensor and a visual sensor), usually adopting simple fusion approaches between the two modalities. As both thermal sensors and visual sensors have their own shortcomings and strengths, we propose a novel joint filter-based hand gesture recognition method to simultaneously exploit the strengths and compensate the shortcomings of each. Our study is motivated by the investigation of the mutual supplementation between thermal and visual information in low feature level for the consistent representation of a hand in the presence of varying lighting conditions. Accordingly, our proposed method leverages the thermal sensor's stability against luminance and the visual sensors textural detail, while complementing the low resolution and halo effect of thermal sensors and the weakness against illumination of visual sensors. A conventional region tracking method and a deep convolutional neural network have been leveraged to track the trajectory of a hand gesture and to recognize the hand gesture, respectively. Our experimental results show stability in recognizing a hand gesture against varying lighting conditions based on the contribution of the joint kernels of spatial adjacency and thermal range similarity.

  8. Tracking and Classification of In-Air Hand Gesture Based on Thermal Guided Joint Filter

    Directory of Open Access Journals (Sweden)

    Seongwan Kim

    2017-01-01

    Full Text Available The research on hand gestures has attracted many image processing-related studies, as it intuitively conveys the intention of a human as it pertains to motional meaning. Various sensors have been used to exploit the advantages of different modalities for the extraction of important information conveyed by the hand gesture of a user. Although many works have focused on learning the benefits of thermal information from thermal cameras, most have focused on face recognition or human body detection, rather than hand gesture recognition. Additionally, the majority of the works that take advantage of multiple modalities (e.g., the combination of a thermal sensor and a visual sensor, usually adopting simple fusion approaches between the two modalities. As both thermal sensors and visual sensors have their own shortcomings and strengths, we propose a novel joint filter-based hand gesture recognition method to simultaneously exploit the strengths and compensate the shortcomings of each. Our study is motivated by the investigation of the mutual supplementation between thermal and visual information in low feature level for the consistent representation of a hand in the presence of varying lighting conditions. Accordingly, our proposed method leverages the thermal sensor’s stability against luminance and the visual sensors textural detail, while complementing the low resolution and halo effect of thermal sensors and the weakness against illumination of visual sensors. A conventional region tracking method and a deep convolutional neural network have been leveraged to track the trajectory of a hand gesture and to recognize the hand gesture, respectively. Our experimental results show stability in recognizing a hand gesture against varying lighting conditions based on the contribution of the joint kernels of spatial adjacency and thermal range similarity.

  9. Scale and Orientation-Based Background Weighted Histogram for Human Tracking

    Science.gov (United States)

    Laaroussi, Khadija; Saaidi, Abderrahim; Masrar, Mohamed; Satori, Khalid

    2016-09-01

    The Mean Shift procedure is a popular object tracking algorithm since it is fast, easy to implement and performs well in a range of conditions. However, classic Mean Shift tracking algorithm fixes the size and orientation of the tracking window, which limits the performance when the target's orientation and scale change. In this paper, we present a new human tracking algorithm based on Mean Shift technique in order to estimate the position, scale and orientation changes of the target. This work combines moment features of the weight image with background information to design a robust tracking algorithm entitled Scale and Orientation-based Background Weighted Histogram (SOBWH). The experimental results show that the proposed approach SOBWH presents a good compromise between tracking precision and calculation time, also they validate its robustness, especially to large background variation, scale and orientation changes and similar background scenes.

  10. An FPGA based track finder at L1 for CMS at the High Luminosity LHC

    CERN Document Server

    Amstutz, Christian; Balzer, Matthias Norbert; Brooke, James John; Calligaris, Luigi; Cieri, Davide; Clement, Emyr John; Hall, Geoffrey; Harbaum, Tanja Renate; Harder, Kristian; Hobson, Peter; Iles, Gregory Michiel; James, Thomas Owen; Manolopoulos, Konstantinos; Matsushita, Takashi; Morton, Alexander; Newbold, David; Paramesvaran, Sudarshan; Pesaresi, Mark Franco; Reid, Ivan; Rose, A. W; Sander, Oliver; Schuh, Thomas; Shepherd-Themistocleous, Claire; Shtipliyski, Antoni; Summers, Sioni Paris; Tapper, Alexander; Tomalin, Ian; Uchida, Kirika; Vichoudis, Paschalis; Weber, M

    2016-01-01

    A new CMS Tracker is under development for operation at the High Luminosity LHC from 2025. It includes an outer tracker based on PT-modules which will construct tracker stubs, built by correlating clusters in two closely spaced sensor layers for the rejection of low transverse momentum track hits, and transmit them off-detector at 40MHz. If tracker data is to contribute to maintaining the Level-1 trigger rate under increased luminosity, a crucial component of the upgrade will be the ability to identify tracks with transverse momentum above 3GeV/c by building tracks out of stubs. A concept for an FPGA-based track finder using a fully time-multiplexed spatially pipelined architecture is presented, where track candidates are identified using a projective binning algorithm. Results from a hardware demonstrator system, where a slice of the track trigger will be constructed to help gauge the performance and requirements for a full system, will be included.

  11. RPC based 5D tracking concept for high multiplicity tracking trigger

    Science.gov (United States)

    Aielli, G.; Camarri, P.; Cardarelli, R.; Di Ciaccio, A.; Distante, L.; Liberti, B.; Paolozzi, L.; Pastori, E.; Santonico, R.

    2017-01-01

    The recently approved High Luminosity LHC project (HL-LHC) and the future colliders proposals present a challenging experimental scenario, dominated by high pileup, radiation background and a bunch crossing time possibly shorter than 5 ns. This holds as well for muon systems, where RPCs can play a fundamental role in the design of the future experiments. The RPCs, thanks to their high space-time granularity, allows a sparse representation of the particle hits, in a very large parametric space containing, in addition to 3D spatial localization, also the pulse time and width associated to the avalanche charge. This 5D representation of the hits can be exploited to improve the performance of complex detectors such as muon systems and increase the discovery potential of a future experiment, by allowing a better track pileup rejection and sharper momentum resolution, an effective measurement of the particle velocity, to tag and trigger the non-ultrarelativistic particles, and the detection local multiple track events in close proximity without ambiguities. Moreover, due to the fast response, typically for RPCs of the order of a few ns, this information can be provided promptly to the lowest level trigger. We will discus theoretically and experimentally the principles and performance of this original method.

  12. An autotuning respiration compensation system based on ultrasound image tracking.

    Science.gov (United States)

    Kuo, Chia-Chun; Chuang, Ho-Chiao; Teng, Kuan-Ting; Hsu, Hsiao-Yu; Tien, Der-Chi; Wu, Chih-Jen; Jeng, Shiu-Chen; Chiou, Jeng-Fong

    2016-11-22

    The purpose of this study was to develop an ultrasound image tracking algorithm (UITA) for extracting the exact displacement of internal organs caused by respiratory motion. The program can track organ displacements in real time, and analyze the displacement signals associated with organ displacements via a respiration compensating system (RCS). The ultrasound imaging system is noninvasive and has a high spatial resolution and a high frame rate (around 32 frames/s), which reduces the radiation doses that patients receive during computed tomography and X-ray observations. This allows for the continuous noninvasive observation and compensation of organ displacements simultaneously during a radiation therapy session.This study designed a UITA for tracking the motion of a specific target, such as the human diaphragm. Simulated diaphragm motion driven by a respiration simulation system was observed with an ultrasound imaging system, and then the induced diaphragm displacements were calculated by our proposed UITA. These signals were used to adjust the gain of the RCS so that the amplitudes of the compensation signals were close to the target movements. The inclination angle of the ultrasound probe with respect to the surface of the abdomen affects the results of ultrasound image displacement tracking. Therefore, the displacement of the phantom was verified by a LINAC with different inclination-angle settings of the ultrasound probe. The experimental results indicate that the best inclination angle of the ultrasound probe is 40 degrees, since this results in the target displacement of the ultrasound images being close to the actual target motion. The displacement signals of the tracking phantom and the opposing displacement signals created by the RCS were compared to assess the positioning accuracy of our proposed ultrasound image tracking technique combined with the RCS.When the ultrasound probe was inclined by 40 degrees in simulated respiration experiments using sine

  13. A Position Controller Model on Color-Based Object Tracking using Fuzzy Logic

    Science.gov (United States)

    Cahyo Wibowo, Budi; Much Ibnu Subroto, Imam; Arifin, Bustanul

    2017-04-01

    Robotics vision is applying technology on the camera to view the environmental conditions as well as the function of the human eye. Colour object tracking system is one application of robotics vision technology with the ability to follow the object being detected. Several methods have been used to generate a good response position control, but most are still using conventional control approach. Fuzzy logic which includes several step of which is to determine the value of crisp input must be fuzzification. The output of fuzzification is forwarded to the process of inference in which there are some fuzzy logic rules. The inference output forwarded to the process of defuzzification to be transformed into outputs (crisp output) to drive the servo motors on the X-axis and Y-axis. Fuzzy logic control is applied to the color-based object tracking system, the system is successful to follow a moving object with average speed of 7.35 cm/s in environments with 117 lux light intensity.

  14. Evaluating Atlantic tropical cyclone track error distributions based on forecast confidence

    OpenAIRE

    Hauke, Matthew D.

    2006-01-01

    A new Tropical Cyclone (TC) surface wind speed probability product from the National Hurricane Center (NHC) takes into account uncertainty in track, maximum wind speed, and wind radii. A Monte Carlo (MC) model is used that draws from probability distributions based on historic track errors. In this thesis, distributions of forecast track errors conditioned on forecast confidence are examined to determine if significant differences exist in distribution characteristics. Two predictors are ...

  15. Hybrid Visual Servoing Control for Robotic Arc Welding Based on Structured Light Vision

    Institute of Scientific and Technical Information of China (English)

    XUDe; WANGLin-Kun; TUZhi-Guo; TANMin

    2005-01-01

    A novel hybrid visual servoing control method based on structured light vision is proposed for robotic arc welding with a general six degrees of freedom robot. It consists of a position control inner-loop in Cartesian space and two outer-loops. One is position-based visual control inCartesian space for moving in the direction of weld seam, i.e., weld seam tracking, another is imagebased visual control in image space for adjustment to eliminate the errors in the process of tracking.A new Jacobian matrix from image space of the feature point on structured light stripe to Cartesian space is provided for differential movement of the end-effector. The control system model is simplified and its stability is discussed. An experiment of arc welding protected by gas CO2 for verifying is well conducted.

  16. Multiple extended target tracking algorithm based on Gaussian surface matrix

    Institute of Scientific and Technical Information of China (English)

    Jinlong Yang; Peng Li; Zhihua Li; Le Yang

    2016-01-01

    In this paper, we consider the problem of irregular shapes tracking for multiple extended targets by introducing the Gaussian surface matrix (GSM) into the framework of the random finite set (RFS) theory. The Gaussian surface function is constructed first by the measurements, and it is used to define the GSM via a mapping function. We then integrate the GSM with the probability hypothesis density (PHD) filter, the Bayesian recursion formulas of GSM-PHD are derived and the Gaussian mixture implementation is employed to obtain the closed-form solutions. Moreover, the estimated shapes are designed to guide the measurement set sub-partition, which can cope with the problem of the spatialy close target tracking. Simulation results show that the proposed algorithm can effectively estimate irregular target shapes and exhibit good robustness in cross extended target tracking.

  17. Approximation-error-ADP-based optimal tracking control for chaotic systems with convergence proof

    Science.gov (United States)

    Song, Rui-Zhuo; Xiao, Wen-Dong; Sun, Chang-Yin; Wei, Qing-Lai

    2013-09-01

    In this paper, an optimal tracking control scheme is proposed for a class of discrete-time chaotic systems using the approximation-error-based adaptive dynamic programming (ADP) algorithm. Via the system transformation, the optimal tracking problem is transformed into an optimal regulation problem, and then the novel optimal tracking control method is proposed. It is shown that for the iterative ADP algorithm with finite approximation error, the iterative performance index functions can converge to a finite neighborhood of the greatest lower bound of all performance index functions under some convergence conditions. Two examples are given to demonstrate the validity of the proposed optimal tracking control scheme for chaotic systems.

  18. Fast polarization-state tracking scheme based on radius-directed linear Kalman filter.

    Science.gov (United States)

    Yang, Yanfu; Cao, Guoliang; Zhong, Kangping; Zhou, Xian; Yao, Yong; Lau, Alan Pak Tao; Lu, Chao

    2015-07-27

    We propose and experimentally demonstrate a fast polarization tracking scheme based on radius-directed linear Kalman filter. It has the advantages of fast convergence and is inherently insensitive to phase noise and frequency offset effects. The scheme is experimentally compared to conventional polarization tracking methods on the polarization rotation angular frequency. The results show that better tracking capability with more than one order of magnitude improvement is obtained in the cases of polarization multiplexed QPSK and 16QAM signals. The influences of the filter tuning parameters on tracking performance are also investigated in detail.

  19. Current status and prospects of nuclear physics research based on tracking techniques

    Science.gov (United States)

    Alekseev, V. A.; Alexandrov, A. B.; Bagulya, A. V.; Chernyavskiy, M. M.; Goncharova, L. A.; Gorbunov, S. A.; Kalinina, G. V.; Konovalova, N. S.; Okatyeva, N. M.; Pavlova, T. A.; Polukhina, N. G.; Shchedrina, T. V.; Starkov, N. I.; Tioukov, V. E.; Vladymirov, M. S.; Volkov, A. E.

    2017-01-01

    Results of nuclear physics research made using track detectors are briefly reviewed. Advantages and prospects of the track detection technique in particle physics, neutrino physics, astrophysics and other fields are discussed on the example of the results of the search for direct origination of tau neutrino in a muon neutrino beam within the framework of the international experiment OPERA (Oscillation Project with Emulsion-tRacking Apparatus) and works on search for superheavy nuclei in nature on base of their tracks in meteoritic olivine crystals. The spectra of superheavy elements in galactic cosmic rays are presented. Prospects of using the track detection technique in fundamental and applied research are reported.

  20. FPGA-Based Approach to Level-1 Track Finding at CMS for the HL-LHC

    CERN Document Server

    Bartz, Edward Hugo; Gershtein, Yury; Halkiadakis, Eva; Hildreth, Michael; Kyriacou, Savvas; Lannon, Kevin Patrick; Lefeld, Anthony James; Ryd, Anders Per Erik; Skinnari, Louise; Stone, Robert; Strohman, Charles Ralph; Tao, Zhengcheng; Winer, Brian; Wittich, Peter; Zientek, Margaret Eldridge

    2017-01-01

    During the High Luminosity LHC, to maintain a manageable trigger rate and achieve its physics goals, the CMS detector will need charged particle tracking at the hardware trigger level. The tracklet approach is a track-finding algorithm based on a road-search algorithm that has been implemented on commercially available FPGA technology. This algorithm has achieved high performance in track-finding and completes tracking within 3.4 $\\mu$s on a Xilinx Virtex-7 FPGA. An overview of the algorithm and its implementation on an FPGA is given, results are shown from a demonstrator test stand and system performance studies are presented.

  1. Maneuvering Vehicle Tracking Based on Multi-sensor Fusion

    Institute of Scientific and Technical Information of China (English)

    CHENYing; HANChong-Zhao

    2005-01-01

    Maneuvering targets tracking is a fundamental task in intelligent vehicle research. This paper focuses on the problem of fusion between radar and image sensors in targets tracking. In order to improve positioning accuracy and narrow down the image working area, a novel method that integrates radar filter with image intensity is proposed to establish an adaptive vision window.A weighted Hausdorff distance is introduced to define the functional relationship between image and model projection, and a modified simulated annealing algorithm is used to find optimum orientation parameter. Furthermore, the global state is estimated, which refers to the distributed data fusion algorithm. Experiment results show that our method is accurate.

  2. An eddy tracking algorithm based on dynamical systems theory

    Science.gov (United States)

    Conti, Daniel; Orfila, Alejandro; Mason, Evan; Sayol, Juan Manuel; Simarro, Gonzalo; Balle, Salvador

    2016-11-01

    This work introduces a new method for ocean eddy detection that applies concepts from stationary dynamical systems theory. The method is composed of three steps: first, the centers of eddies are obtained from fixed points and their linear stability analysis; second, the size of the eddies is estimated from the vorticity between the eddy center and its neighboring fixed points, and, third, a tracking algorithm connects the different time frames. The tracking algorithm has been designed to avoid mismatching connections between eddies at different frames. Eddies are detected for the period between 1992 and 2012 using geostrophic velocities derived from AVISO altimetry and a new database is provided for the global ocean.

  3. Symmetric Kullback-Leibler Metric Based Tracking Behaviors for Bioinspired Robotic Eyes.

    Science.gov (United States)

    Liu, Hengli; Luo, Jun; Wu, Peng; Xie, Shaorong; Li, Hengyu

    2015-01-01

    A symmetric Kullback-Leibler metric based tracking system, capable of tracking moving targets, is presented for a bionic spherical parallel mechanism to minimize a tracking error function to simulate smooth pursuit of human eyes. More specifically, we propose a real-time moving target tracking algorithm which utilizes spatial histograms taking into account symmetric Kullback-Leibler metric. In the proposed algorithm, the key spatial histograms are extracted and taken into particle filtering framework. Once the target is identified, an image-based control scheme is implemented to drive bionic spherical parallel mechanism such that the identified target is to be tracked at the center of the captured images. Meanwhile, the robot motion information is fed forward to develop an adaptive smooth tracking controller inspired by the Vestibuloocular Reflex mechanism. The proposed tracking system is designed to make the robot track dynamic objects when the robot travels through transmittable terrains, especially bumpy environment. To perform bumpy-resist capability under the condition of violent attitude variation when the robot works in the bumpy environment mentioned, experimental results demonstrate the effectiveness and robustness of our bioinspired tracking system using bionic spherical parallel mechanism inspired by head-eye coordination.

  4. Research on Method of Multisensor Distributed Track Fusion Based on Feedback Integration

    Institute of Scientific and Technical Information of China (English)

    YANGGuosheng; WENChenglin; TANMin

    2003-01-01

    Multisensor distributed track fusion based on feedback integration is studied in this paper. Firstly,the tracking algorithms of each sensor in local (processor)and the track fusion algorithm on the basis of global in-formation in center (processor) are given after the general structure of multisensor distributed track fusion based on feedback integration is put forward. Secondly, one step tar-get state predictions along with covariance matrixes are fed back to the interrelated sensors to form new tracking gates for the corresponding targets, and then the intersection of the new tracking gate and the original gate formed before feedback for a certain target is taken as the effective track-ing gate for the next estimation, to decrease the computing load of PDA (probability data association). In addition,target instantiation is given to the sensor that has not ob-tained the target track, while other sensors have obtained.At last, take IR and radar as an example, simulation re-searches are performed both on the original algorithm and the one presented by this paper.

  5. Automatic detection of suspicious behavior of pickpockets with track-based features in a shopping mall

    NARCIS (Netherlands)

    Bouma, H.; Baan, J.; Burghouts, G.J.; Eendebak, P.T.; Huis, J.R. van; Dijk, J.; Rest, J.H.C. van

    2014-01-01

    Proactive detection of incidents is required to decrease the cost of security incidents. This paper focusses on the automatic early detection of suspicious behavior of pickpockets with track-based features in a crowded shopping mall. Our method consists of several steps: pedestrian tracking, feature

  6. Real-time seam tracking for robotic laser welding using trajectory-based control

    NARCIS (Netherlands)

    Graaf, de Menno; Aarts, Ronald; Jonker, Ben; Meijer, Johan

    2010-01-01

    In this paper a real-time seam tracking algorithm is proposed that can cope with the accuracy demands of robotic laser welding. A trajectory-based control architecture is presented, which had to be developed for this seam tracking algorithm. Cartesian locations (position and orientation) are added t

  7. 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...

  8. Prior Knowledge and Online Inquiry-Based Science Reading: Evidence from Eye Tracking

    Science.gov (United States)

    Ho, Hsin Ning Jessie; Tsai, Meng-Jung; Wang, Ching-Yeh; Tsai, Chin-Chung

    2014-01-01

    This study employed eye-tracking technology to examine how students with different levels of prior knowledge process text and data diagrams when reading a web-based scientific report. Students' visual behaviors were tracked and recorded when they read a report demonstrating the relationship between the greenhouse effect and global climate…

  9. Prior Knowledge and Online Inquiry-Based Science Reading: Evidence from Eye Tracking

    Science.gov (United States)

    Ho, Hsin Ning Jessie; Tsai, Meng-Jung; Wang, Ching-Yeh; Tsai, Chin-Chung

    2014-01-01

    This study employed eye-tracking technology to examine how students with different levels of prior knowledge process text and data diagrams when reading a web-based scientific report. Students' visual behaviors were tracked and recorded when they read a report demonstrating the relationship between the greenhouse effect and global climate…

  10. A Sensor-based SLAM Algorithm for Camera Tracking vin Virtual Studio

    Institute of Scientific and Technical Information of China (English)

    Po Yang; Wenyan Wu; Mansour Moniri; Claude C. Chibelushi

    2008-01-01

    This paper addresses a sensor-based simultaneous localization and mapping (SLAM) algorithm for camera tracking in a virtual studio environment. The traditional camera tracking methods in virtual studios are vision-based or sensor-based. However, the chroma keying process in virtual studios requires color cues, such as blue background, to segment foreground objects to be inserted into images and videos. Chroma keying limits the application of vision-based tracking methods in virtual studios since the background cannot provide enough feature information. Furthermore, the conventional sensor-based tracking approaches suffer from the jitter, drift or expensive computation due to the characteristics of individual sensor system. Therefore, the SLAM techniques from the mobile robot area are first investigated and adapted to the camera tracking area. Then, a sensor-based SLAM extension algorithm for two dimensional (2D) camera tracking in virtual studio is described. Also, a technique called map adjustment is proposed to increase the accuracy and efficiency of the algorithm. The feasibility and robustness of the algorithm is shown by experiments. The simulation results demonstrate that the sensor-based SLAM algorithm can satisfy the fundamental 2D camera tracking requirement in virtual studio environment.

  11. Triplet based online track finding in the PANDA-STT

    Science.gov (United States)

    Mertens, Marius C.; Brinkmann, Kai-Thomas; Ritman, James; Wintz, Peter

    2014-05-01

    We present a method for online track finding in the PANDA-STT which requires only knowledge of the time and straw position of the hits. Therefore, it does not depend on any additional information such as the drift-time or radius drift-time calibration which may not be present ab-initio.

  12. Laser-based target tracking using principal component descriptors

    CSIR Research Space (South Africa)

    Burke, Michael G

    2010-11-01

    Full Text Available . [2] L. E. Navarro-Serment, C. Mertz, and M. Hebert, “Predictive mover detection and tracking in cluttered environments,” in Proc. of the 25th. Army Science Conference, November 2006. [3] J. Xavier, M. Pacheco, D. Castro, and A. Ruano, “Fast line...

  13. Vision-Based Grasp Tracking for Planar Objects

    NARCIS (Netherlands)

    Recatala, Gabriel; Carloni, Raffaella; Melchiorri, Claudio; Sanz, Pedro J.; Cervera, Enric; del Pobil, Angel P.

    In robotics, the manipulation of a priori unknown objects involves several steps and problems that must be carefully considered and solved by proper planning and control algorithms. For example, once suitable contact points have been computed, the control system should be able to track them in the

  14. Neural network based satellite tracking for deep space applications

    Science.gov (United States)

    Amoozegar, F.; Ruggier, C.

    2003-01-01

    The objective of this paper is to provide a survey of neural network trends as applied to the tracking of spacecrafts in deep space at Ka-band under various weather conditions and examine the trade-off between tracing accuracy and communication link performance.

  15. Tracking fs light pulses in space and time through advanced photonic structures

    NARCIS (Netherlands)

    Kuipers, L.; Gersen, H.; Balistreri, M.L.M.; Korterik, Jeroen P.; van Hulst, N.F.

    2003-01-01

    The propagation of short light pulses through advanced photonic structures like photonic crystals is influenced by the interplay of various physical mechanisms, for instance by the strong material dispersion and the low group velocity. To study the complex interplay between different mechanisms as

  16. A Cross Structured Light Sensor and Stripe Segmentation Method for Visual Tracking of a Wall Climbing Robot.

    Science.gov (United States)

    Zhang, Liguo; Sun, Jianguo; Yin, Guisheng; Zhao, Jing; Han, Qilong

    2015-06-11

    In non-destructive testing (NDT) of metal welds, weld line tracking is usually performed outdoors, where the structured light sources are always disturbed by various noises, such as sunlight, shadows, and reflections from the weld line surface. In this paper, we design a cross structured light (CSL) to detect the weld line and propose a robust laser stripe segmentation algorithm to overcome the noises in structured light images. An adaptive monochromatic space is applied to preprocess the image with ambient noises. In the monochromatic image, the laser stripe obtained is recovered as a multichannel signal by minimum entropy deconvolution. Lastly, the stripe centre points are extracted from the image. In experiments, the CSL sensor and the proposed algorithm are applied to guide a wall climbing robot inspecting the weld line of a wind power tower. The experimental results show that the CSL sensor can capture the 3D information of the welds with high accuracy, and the proposed algorithm contributes to the weld line inspection and the robot navigation.

  17. Fast 4$\\pi$ track reconstruction in nuclear emulsion detectors based on GPU technology

    CERN Document Server

    Ariga, A

    2013-01-01

    Fast 4$\\pi$ solid angle particle track recognition has been a challenge in particle physics for a long time, especially in using nuclear emulsion detectors. The recent advances in computing technology opened the way for its realization. A fast 4$\\pi$ solid angle particle track reconstruction based on GPU technology combined with a multithread programming is reported here with a detailed comparison between GPU-based and CPU-based programming. A 60 times faster processing of 3D emulsion detector data, corresponding to processing of 15 cm$^2$ emulsion surface scanned per hour, has been achieved by GPUs with an excellent tracking performance.

  18. Conflict Resolution in Aceh in Light of Track One and a Half Diplomacy

    Directory of Open Access Journals (Sweden)

    Robert M. Heiling

    2008-01-01

    Full Text Available This paper analyzes the role of mediators in the resolution of the Aceh conflict within the framework of a three-step process. Two separate mediation efforts, one conducted by the Centre for Humanitarian Dialogue from 1999 until 2003 and a second one led by Martti Ahtisaari and his Crisis Management Initiative in 2004/2005, attempted to solve the Aceh confl ict. The author shows that beside contextual factors such as ripeness of the conflict and advantageous relations between and characteristics of the conflict parties, the success of Ahtisaari’s engagement can be further explained by procedural factors. These include mediator behaviour and mediation strategies. Furthermore the mediator’s ability to use contacts with official track one actors was crucial in securing the signing as well as the implementation of the present peace agreement. ----- Der Artikel analysiert die Rolle von Mediatoren in der Lösung des Aceh Konfl ikts mittels eines drei-Phasen Modells von Konfliktlösung. Zwei voneinander unabhängige Mediationsverfahren, jenes des Centre for Humanitarian Dialogue von 1999 bis 2003, und ein weiteres geleitet durch Martti Ahtisaari und seiner Crisis Management Initiative in 2004/2005, zielten darauf ab den Konflikt zu lösen. Der Autor zeigt, dass neben kontextuellen Faktoren wie einer “ripeness” des Konflikts sowie günstigen Veränderungen auf Seite der Konfliktparteien, prozedurale Faktoren für den Erfolg Ahtisaaris entscheidend waren. Diese Faktoren beziehen sich auf das Agieren und die Strategien des Mediators. Die Fähigkeit des Mediators, Kontakte zu offiziellen “track one” Akteuren aktiv während des Mediationsprozesses zu nutzen, bildete einen Schlüsselfaktor darin einen Friedensschluss und im weiteren Verlauf eine weitgehend erfolgreiche Umsetzung des aktuellen Abkommens zwischen den ehemaligen Konfliktparteien zu erreichen.

  19. Autonomous Sub-Pixel Satellite Track Endpoint Determination for Space Based Images

    Energy Technology Data Exchange (ETDEWEB)

    Simms, L M

    2011-03-07

    An algorithm for determining satellite track endpoints with sub-pixel resolution in spaced-based images is presented. The algorithm allows for significant curvature in the imaged track due to rotation of the spacecraft capturing the image. The motivation behind the subpixel endpoint determination is first presented, followed by a description of the methodology used. Results from running the algorithm on real ground-based and simulated spaced-based images are shown to highlight its effectiveness.

  20. PLC based Smart Street Lighting Control

    Directory of Open Access Journals (Sweden)

    D.V.Pushpa Latha

    2013-12-01

    Full Text Available Conventional street lighting systems in most of the areas are Online at regular intervals of time irrespective of the seasonal variations. The street lights are simply switched on at afternoon and turned off in the morning. The consequence is that a large amount of Power is wasted meaninglessly. As energy consumption is an issue of increasing interest, possible energy savings in public street lighting systems are recently discussed from different viewpoints. The purpose of this work is to describe the Smart Street Lighting system, an approach to accomplish the demand for flexible public lighting systems using a Programmable Logic controller (PLC. The main difference from other computers is that PLCs are armoured for severe conditions such as dust, moisture, heat, cold etc., and have the facility for extensive input/output (I/O arrangements. In the proposed paper, street lights are controlled using millennium 3 PLC taking the seasonal variations into consideration.

  1. Dictionary learning-based spatiotemporal regularization for 3D dense speckle tracking

    Science.gov (United States)

    Lu, Allen; Zontak, Maria; Parajuli, Nripesh; Stendahl, John C.; Boutagy, Nabil; Eberle, Melissa; O'Donnell, Matthew; Sinusas, Albert J.; Duncan, James S.

    2017-03-01

    Speckle tracking is a common method for non-rigid tissue motion analysis in 3D echocardiography, where unique texture patterns are tracked through the cardiac cycle. However, poor tracking often occurs due to inherent ultrasound issues, such as image artifacts and speckle decorrelation; thus regularization is required. Various methods, such as optical flow, elastic registration, and block matching techniques have been proposed to track speckle motion. Such methods typically apply spatial and temporal regularization in a separate manner. In this paper, we propose a joint spatiotemporal regularization method based on an adaptive dictionary representation of the dense 3D+time Lagrangian motion field. Sparse dictionaries have good signal adaptive and noise-reduction properties; however, they are prone to quantization errors. Our method takes advantage of the desirable noise suppression, while avoiding the undesirable quantization error. The idea is to enforce regularization only on the poorly tracked trajectories. Specifically, our method 1.) builds data-driven 4-dimensional dictionary of Lagrangian displacements using sparse learning, 2.) automatically identifies poorly tracked trajectories (outliers) based on sparse reconstruction errors, and 3.) performs sparse reconstruction of the outliers only. Our approach can be applied on dense Lagrangian motion fields calculated by any method. We demonstrate the effectiveness of our approach on a baseline block matching speckle tracking and evaluate performance of the proposed algorithm using tracking and strain accuracy analysis.

  2. VIDEO MULTI-TARGET TRACKING BASED ON PROBABILISTIC GRAPHICAL MODEL

    Institute of Scientific and Technical Information of China (English)

    Xu Feng; Huang Chenrong; Wu Zhengjun; Xu Lizhong

    2011-01-01

    In the technique of video multi-target tracking,the common particle filter can not deal well with uncertain relations among multiple targets.To solve this problem,many researchers use data association method to reduce the multi-target uncertainty.However,the traditional data association method is difficult to track accurately when the target is occluded.To remove the occlusion in the video,combined with the theory of data association,this paper adopts the probabilistic graphical model for multi-target modeling and analysis of the targets relationship in the particle filter framework.Experimental results show that the proposed algorithm can solve the occlusion problem better compared with the traditional algorithm.

  3. Nuclear track-based biosensors with the enzyme laccase

    Science.gov (United States)

    García-Arellano, H.; Fink, D.; Muñoz Hernández, G.; Vacík, J.; Hnatowicz, V.; Alfonta, L.

    2014-08-01

    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.

  4. TRACKING DYNAMIC CHANGES AND MONITORING SOCIOECONOMIC PARAMETERS IN ALGERIA BETWEEN 1993 AND 2012, USING NIGHTTIME LIGHT REMOTE SENSING

    Directory of Open Access Journals (Sweden)

    B. Faouzi

    2017-09-01

    Full Text Available This paper is based on using DMSP-OLS data from satellites nighttime light observations to detect both sources of light emissions in Algeria from human settlement areas and gas flaring from oil-extraction and natural gas production. We used the time series of data from DMSP-OLS images to examine the spatial and temporal characteristics of urban development in 48 Algerian provinces from 1993 to 2012. A systematic nighttime light calibration method was used to improve the consistency and comparability of the DSMPOSL images and then a separation is made between light detected from human settlements and light detected from gas flaring in order to allow us to study human settlements without other light emissions and then assess the suitability of using DMSP data in southern Algeria and its ability to monitor gas flaring. Linear regression methods were developed to identify the dynamic change of nighttime light and estimated its growth directions at pixel level. This work is the first to use nighttime light observations to detect and monitor the growth of human settlements in North Africa. In this study, we made use of DMSP-OLS data as a return ticket to the years of crises and we found the most affected provinces during that period. The DMSP-OLS data proved to be an index of growth in the economy during the period of stability in Algeria expressed by positive dynamic changes in the lighted area in all Algerian provinces. We used NTL data as an alternative to annual growth indexes for each province, which are unavailable, and its help as a monitoring system for socioeconomic parameters to fill the gap of data availability. We also proposed nighttime light remote sensing data as a useful tool to control and reduce CO2 emissions in Algeria’s petroleum sector.

  5. Track detector based dosimetry for therapeutic carbon beams

    CERN Document Server

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

    2013-01-01

    The ability of plastic and fluorescent nuclear track detectors (PNTDs and FNTDs) to measure fluence and the linear energy transfer (LET) of clinical carbon ion beams was investigated. We employed coincident measurements with both systems and registered the results at the level of single tracks. Irradiations were performed in the entrance channel of the monoenergetic carbon ion beam covering the therapeutically useful 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. Additionally, a relationship between the mean LET as determined with PNTDs and the mean fluorescence amplitude of the p...

  6. 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.

  7. Optical design and lighting application of an LED-based sports lighting system

    Science.gov (United States)

    Boxler, Larry

    2011-10-01

    This paper describes both the optical development of an LED-based sports lighting system and the results of the application of the system to an actual sport field. A traditional sport lighting fixture is generally composed of a single 1500 watt High Intensity Discharge (HID) light source with reflectors used to control the light distribution. The efficacy of the HID light source is equivalent or nearly equivalent to most LED light sources, putting LEDs at a large cost disadvantage in a high light output application such as sports lighting due to the number of LEDs and supporting components required to run an LED system. To assess the feasibility and applicability of LEDs in a sports lighting application, an LED-based sport light has been developed and installed on a small soccer field specified to have an average maintained illuminance level of 30 footcandles. An existing HID sport lighting system was also installed on the same size soccer field adjacent to the LED field with the same average footcandle level for comparison. Results indicate that LEDs can provide equivalent average illumination; however the LED source and system component cost is substantially higher. Despite the high cost, it was found that improved optical control afforded by the optical design used in the system provides a significant improvement in offsite wasted spill light, glare control, and on field uniformity. This could provide an advantage for LED systems.

  8. Unstable nuclei in dissociation of light stable and radioactive nuclei in nuclear track emulsion

    CERN Document Server

    Artemenkov, D A; Zarubin, P I

    2016-01-01

    A role of the unstable nuclei ${}^{6}$Be, ${}^{8}$Be and ${}^{9}$B in the dissociation of relativistic nuclei ${}^{7,9}$Be, ${}^{10}$B and ${}^{10,11}$C is under study on the basis of nuclear track emulsion exposed to secondary beams of the JINR Nuclotron. Contribution of the configuration ${}^{6}$Be + $\\mit{n}$ to the ${}^{7}$Be nucleus structure is 8 $\\pm$ 1% which is near the value for the configuration ${}^{6}$Li + $\\mit{p}$. Distributions over the opening angle of $\\alpha$-particle pairs indicate to a simultaneous presence of virtual ${}^{8}$Be$_{g.s.}$ and ${}^{8}$Be$_{2^+}$ states in the ground states of the ${}^{9}$Be and ${}^{10}$C nuclei. The core ${}^{9}$B is manifested in the {${}^{10}$C} nucleus with a probability of 30 $\\pm$ 4%. Selection of the ${}^{10}$C "white" stars accompanied by ${}^{8}$Be$_{g.s.}$ (${}^{9}$B) leads to appearance in the excitation energy distribution of 2$\\alpha$2$\\mit{p}$ "quartets" of the distinct peak with a maximum at 4.1 $\\pm$ 0.3 MeV. ${}^{8}$Be$_{g.s.}$ decays are p...

  9. Mean shift-based object tracking in FLIR imagery using multiple features

    Science.gov (United States)

    Yang, Wei; Li, Junshan; Shi, Deqin; Cheng, Wen

    2009-10-01

    A novel object tracking algorithm for FLIR imagery based on mean shift using multiple features is proposed to improve the tracking performance. First, the appearance model of infrared object is represented in the combination of gray space, LBP texture space, and orientation space with different feature weight. And then, the mean shift algorithm is employed to find the object location. An on-line feature weight update mechanism is developed based on Fisher criteria, which measure the discrimination of object and background effectively. Experiment results demonstrate the effectiveness and robustness of the proposed method for object tracking in FLIR imagery.

  10. Backstepping based Trajectory Tracking Control of a Four Wheeled Mobile Robot

    Directory of Open Access Journals (Sweden)

    Nagarajan Sukavanam

    2008-11-01

    Full Text Available For a four wheeled mobile robot a trajectory tracking concept is developed based on its kinematics. A trajectory is a time?indexed path in the plane consisting of position and orientation .The mobile robot is modeled as a non holonomic system subject to pure rolling , no slip constraints.To facilitate the controller design the kinematic equation can be converted into chained form using some change of co-ordinates.From the kinematic model of the robot a backstepping based tracking controller is derived. Simulation results demonstrate such trajectory tracking strategy for the kinematics indeed gives rise to an effective methodology to follow the desired trajectory asymptotically.

  11. Trends in Correlation-Based Pattern Recognition and Tracking in Forward-Looking Infrared Imagery

    Science.gov (United States)

    Alam, Mohammad S.; Bhuiyan, Sharif M. A.

    2014-01-01

    In this paper, we review the recent trends and advancements on correlation-based pattern recognition and tracking in forward-looking infrared (FLIR) imagery. In particular, we discuss matched filter-based correlation techniques for target detection and tracking which are widely used for various real time applications. We analyze and present test results involving recently reported matched filters such as the maximum average correlation height (MACH) filter and its variants, and distance classifier correlation filter (DCCF) and its variants. Test results are presented for both single/multiple target detection and tracking using various real-life FLIR image sequences. PMID:25061840

  12. Multi-Deme Parallel FGAs-Based Algorithm for Multitarget Tracking

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For data association in multisensor and multitarget tracking, a novel parallel algorithm is developed to improve the efficiency and real-time performance of FGAs-based algorithm. One Cluster of Workstation (COW) with Message Passing Interface (MPI) is built. The proposed Multi-Deme Parallel FGA (MDPFGA) is run on the platform. A serial of special MDPFGAs are used to determine the static and the dynamic solutions of generalized m-best S-D assignment problem respectively, as well as target states estimation in track management. Such an assignment-based parallel algorithm is demonstrated on simulated passive sensor track formation and maintenance problem. While illustrating the feasibility of the proposed algorithm in multisensor multitarget tracking, simulation results indicate that the MDPFGAs-based algorithm has greater efficiency and speed than the FGAs-based algorithm.

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

    National Research Council Canada - National Science Library

    Mousumi Ahmed; Kamesh Subbarao

    2016-01-01

    ...) 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...

  14. 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.

  15. Pixel Intensity Based Cumulative Features for Moving Object Tracking (MOT) in Darkness

    Science.gov (United States)

    Saba, Tanzila

    2016-06-01

    Moving Object Tracking (MOT) is one of the frequent used tasks in computer vision systems and on the same time a challenging issue particularly in darkness. Vehicle tracking involves finding new position of vehicles in consecutive frames. This paper presents MOT algorithm that is developed for advanced driver safety applications like automatic high beam control, forward collision warning. Accordingly, the proposed approach targets vehicle tracking in the dark environment. Hence, a camera is mounted on the host vehicle to capture video frames of the traffic ahead. The scope involves tracking of both oncoming and preceding vehicles. The vehicles are tracked in consecutive frames using grayscale information and robust structure features. The features representation of the vehicle region is based on cumulative pixel intensity information. The implementation for feature extraction is optimized by using a dynamic programming approach to meet the constraints of a real time application. Simulation results thus obtained are promising in state of the art.

  16. A new Recommender system based on target tracking: a Kalman Filter approach

    CERN Document Server

    Nowakowski, Samuel; Boyer, Anne

    2010-01-01

    In this paper, we propose a new approach for recommender systems based on target tracking by Kalman filtering. We assume that users and their seen resources are vectors in the multidimensional space of the categories of the resources. Knowing this space, we propose an algorithm based on a Kalman filter to track users and to predict the best prediction of their future position in the recommendation space.

  17. Target tracking in the recommender space: Toward a new recommender system based on Kalman filtering

    CERN Document Server

    Nowakowski, Samuel; Boyer, Anne

    2010-01-01

    In this paper, we propose a new approach for recommender systems based on target tracking by Kalman filtering. We assume that users and their seen resources are vectors in the multidimensional space of the categories of the resources. Knowing this space, we propose an algorithm based on a Kalman filter to track users and to predict the best prediction of their future position in the recommendation space.

  18. Vision-Based Leader/Follower Tracking for Nonholonomic Mobile Robots

    Science.gov (United States)

    2006-01-01

    06/#1 Title: Vision-based Leader/Follower Tracking for Nonholonomic Mobile Robots Authors: Hariprasad Kannan, Vilas. K. Chitrakaran, Darren. M...for Nonholonomic Mobile Robots 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Vision-Based Leader/Follower Tracking for Nonholonomic Mobile Robots Hariprasad Kannan, Vilas K

  19. Tracking the motion of charges in a terahertz light field byfemtosecond X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Cavalleri, A.; Wall, S.; Simpson, C.; Statz, E.; Ward, D.W.; Nelson, K.A.; Rini, M.; Schoenlein, R.W.

    2006-07-01

    In condensed matter, light propagation near resonances isdescribed in terms of polaritons, electro-mechanical excitations in whichthe time-dependent electric field is coupled to the oscillation ofcharged masses. This description under pins our understanding of themacroscopic optical properties of solids, liquids and plasmas, as well asof their dispersion with frequency. In ferroelectric materials, terahertzradiation propagates by driving infrared-active lattice vibrations,resulting in phononpolariton waves. Electro-optic sampling withfemtosecond optical pulses can measure the time-dependent electricalpolarization, providing a phase-sensitive analogue to optical Ramanscattering. Here we use femtosecond time-resolved X-ray diffraction, aphase-sensitive analogue to inelastic X-ray scattering, to measure thecorresponding displacements of ions in ferroelectric lithium tantalate,LiTaO3. Amplitude and phase of all degrees of freedom in a light fieldare thus directly measured in the time domain. Notably, extension ofother X-ray techniques to the femtosecond timescale (for example,magnetic or anomalous scattering) would allow for studies in complexsystems, where electric fields couple to multiple degrees offreedom.

  20. Spatially Varying Image Based Lighting by Light Probe Sequences, Capture, Processing and Rendering

    OpenAIRE

    Unger, Jonas; Gustavson, Stefan; Ynnerman, Anders

    2007-01-01

    We present a novel technique for capturing spatially or temporally resolved light probe sequences, and using them for image based lighting. For this purpose we have designed and built a real-time light probe, a catadioptric imaging system that can capture the full dynamic range of the lighting incident at each point in space at video frame rates, while being moved through a scene. The real-time light probe uses a digital imaging system which we have programmed to capture high quality, photome...

  1. IMM Filter Based Human Tracking Using a Distributed Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Sen Zhang

    2014-01-01

    Full Text Available This paper proposes a human tracking approach in a distributed wireless sensor network. Most of the efforts on human tracking focus on vision techniques. However, most vision-based approaches to moving object detection involve intensive real-time computations. In this paper, we present an algorithm for human tracking using low-cost range wireless sensor nodes which can contribute lower computational burden based on a distributed computing system, while the centralized computing system often makes some information from sensors delay. Because the human target often moves with high maneuvering, the proposed algorithm applies the interacting multiple model (IMM filter techniques and a novel sensor node selection scheme developed considering both the tracking accuracy and the energy cost which is based on the tacking results of IMM filter at each time step. This paper also proposed a novel sensor management scheme which can manage the sensor node effectively during the sensor node selection and the tracking process. Simulations results show that the proposed approach can achieve superior tracking accuracy compared to the most recent human motion tracking scheme.

  2. Development of white LED based PV lighting systems

    Energy Technology Data Exchange (ETDEWEB)

    Sastry, O.S.; Pant, P.C.; Prasad, G.; Kumar, Rajesh; Bandyopadhyay, Bibek [Solar Energy Centre, Ministry of New and Renewable Energy, Block 14, CGO Complex, Lodhi Road, New Delhi 110003 (India); Kamala Devi, V. [Agency for Non-Conventional Energy and Rural Technology, P.B. No. 1094, Pattom, P.O. Kasavadasapuram, Trivandrum, Kerala 695 004 (India)

    2010-09-15

    A high performance white light emitting diode (WLED) based PV lighting system has been developed under a joint project of SEC and ANERT. The system has been analyzed using the test set-ups developed as a part of advanced lighting laboratory (ALL). The results show that the performance is one of the best among the systems developed in the capacity range. (author)

  3. Geolocation by light

    DEFF Research Database (Denmark)

    Lisovski, Simeon; Hewson, Chris M.; Klaassen, Raymond H. G.

    2012-01-01

    1. Geolocation by light allows for tracking animal movements, based on measurements of light intensity over time by a data-logging device (‘geolocator’). Recent developments of ultra-light devices (<2 g) broadened the range of target species and boosted the number of studies using geolocators. Ho...

  4. Decoherence control: A feedback mechanism based on hamiltonian tracking

    CERN Document Server

    Katz, G; Kosloff, R; Katz, Gil; Ratner, Mark; Kosloff, Ronnie

    2006-01-01

    Enviroment - caused dissipation disrupts the hamiltonian evolution of all quantum systems not fully isolated from any bath. We propose and examine a feedback-control scheme to eliminate such dissipation, by tracking the free hamiltonian evolution. We determine a driving-field that maximizes the projection of the actual molecular system onto the freely propagated one. The evolution of a model two level system in a dephasing bath is followed, and the driving field that overcomes the decoherence is calculated. An implementation of the scheme in the laboratory using feedback control is suggested.

  5. Polymer and small molecule based hybrid light source

    Science.gov (United States)

    Choong, Vi-En; Choulis, Stelios; Krummacher, Benjamin Claus; Mathai, Mathew; So, Franky

    2010-03-16

    An organic electroluminescent device, includes: a substrate; a hole-injecting electrode (anode) coated over the substrate; a hole injection layer coated over the anode; a hole transporting layer coated over the hole injection layer; a polymer based light emitting layer, coated over the hole transporting layer; a small molecule based light emitting layer, thermally evaporated over the polymer based light emitting layer; and an electron-injecting electrode (cathode) deposited over the electroluminescent polymer layer.

  6. Robust and Adaptive Block Tracking Method Based on Particle Filter

    Directory of Open Access Journals (Sweden)

    Bin Sun

    2015-10-01

    Full Text Available In the field of video analysis and processing, object tracking is attracting more and more attention especially in traffic management, digital surveillance and so on. However problems such as objects’ abrupt motion, occlusion and complex target structures would bring difficulties to academic study and engineering application. In this paper, a fragmentsbased tracking method using the block relationship coefficient is proposed. In this method, we use particle filter algorithm and object region is divided into blocks initially. The contribution of this method is that object features are not extracted just from a single block, the relationship between current block and its neighbor blocks are extracted to describe the variation of the block. Each block is weighted according to the block relationship coefficient when the block is voted on the most matched region in next frame. This method can make full use of the relationship between blocks. The experimental results demonstrate that our method can provide good performance in condition of occlusion and abrupt posture variation.

  7. An Asynchronous Neuromorphic Event-Driven Visual Part-Based Shape Tracking.

    Science.gov (United States)

    Reverter Valeiras, David; Lagorce, Xavier; Clady, Xavier; Bartolozzi, Chiara; Ieng, Sio-Hoi; Benosman, Ryad

    2015-12-01

    Object tracking is an important step in many artificial vision tasks. The current state-of-the-art implementations remain too computationally demanding for the problem to be solved in real time with high dynamics. This paper presents a novel real-time method for visual part-based tracking of complex objects from the output of an asynchronous event-based camera. This paper extends the pictorial structures model introduced by Fischler and Elschlager 40 years ago and introduces a new formulation of the problem, allowing the dynamic processing of visual input in real time at high temporal resolution using a conventional PC. It relies on the concept of representing an object as a set of basic elements linked by springs. These basic elements consist of simple trackers capable of successfully tracking a target with an ellipse-like shape at several kilohertz on a conventional computer. For each incoming event, the method updates the elastic connections established between the trackers and guarantees a desired geometric structure corresponding to the tracked object in real time. This introduces a high temporal elasticity to adapt to projective deformations of the tracked object in the focal plane. The elastic energy of this virtual mechanical system provides a quality criterion for tracking and can be used to determine whether the measured deformations are caused by the perspective projection of the perceived object or by occlusions. Experiments on real-world data show the robustness of the method in the context of dynamic face tracking.

  8. Resonant-cavity based monolithic white light-emitting diode

    Science.gov (United States)

    Huang, Lirong; Huang, Dexiu; Wen, Feng

    2007-11-01

    We propose a new scheme of resonant-cavity (RC) based monolithic white LED, it relaxes the hard requirement of high internal quantum efficiency of yellow multi-quantum (MQW) and offers an easy way to obtain high luminous efficacy white light emission. In the proposed white LED, the blue MQW and yellow MQW active layer are embedded in a resonant-cavity defined by the bottom distributed Bragg reflector(DBR) and top DBR. For a optimal design of RC-based white LED, the extraction efficiency for yellow light is enhanced, while that for blue light is suppressed, thus intensity ratio of yellow light in the emitting light is increased, which not only helps to obtain white emission in spite of the low internal quantum efficiency of yellow light, but also doubles luminous efficacy. The color coordinates and luminous flux of the emitting light from RC-based white LED are calculated and the performance dependence on directionality is investigated.

  9. Numerical methods and inversion algorithms in reservoir simulation based on front tracking

    Energy Technology Data Exchange (ETDEWEB)

    Haugse, Vidar

    1999-04-01

    This thesis uses front tracking to analyse laboratory experiments on multiphase flow in porous media. New methods for parameter estimation for two- and three-phase relative permeability experiments have been developed. Up scaling of heterogeneous and stochastic porous media is analysed. Numerical methods based on front tracking is developed and analysed. Such methods are efficient for problems involving steep changes in the physical quantities. Multi-dimensional problems are solved by combining front tracking with dimensional splitting. A method for adaptive grid refinement is developed.

  10. An image-tracking algorithm based on object center distance-weighting and image feature recognition

    Institute of Scientific and Technical Information of China (English)

    JIANG Shuhong; WANG Qin; ZHANG Jianqiu; HU Bo

    2007-01-01

    Areal-time image-tracking algorithm is proposed.which gives small weights to pixels farther from the object center and uses the quantized image gray scales as a template.It identifies the target's location by the mean-shift iteration method and arrives at the target's scale by using image feature recognition.It improves the kernel-based algorithm in tracking scale-changing targets.A decimation mcthod is proposed to track large-sized targets and real-time experimental results verify the effectiveness of the proposed algorithm.

  11. Light extraction efficiency enhancement for fluorescent SiC based white light-emitting diodes

    DEFF Research Database (Denmark)

    Ou, Haiyan; Ou, Yiyu; Argyraki, Aikaterini

    fluorescent Boron-Nitrogen co-doped 6H SiC is optimized in terms of source material, growth condition, dopant concentration, and carrier lifetime by using photoluminescence, pump-probe spectroscopy etc. The internal quantum efficiency is measured and the methods to increase the efficiency have been explored......Fluorescent SiC based white light-emitting diodes(LEDs) light source, as an innovative energy-efficient light source, would even have longer lifetime, better light quality and eliminated blue-tone effect, compared to the current phosphor based white LED light source. In this paper, the yellow....... At a device level, the focus is on improving the light extraction efficiency due to the rather high refractive index of SiC by nanostructuring the surface of SiC. Both periodic nanostructures made by e-beam lithography and nanosphere lithography and random nanostructures made by self-assembled Au nanosphere...

  12. MARCHING CUBES BASED FRONT TRACKING METHOD AND ITS APPLICATION TO SOME INTERFACE INSTABILITY PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    WANG Jing-yi; ZOU Jian-feng; ZHENG Yao; REN An-lu

    2011-01-01

    A front tracking method based on a marching cubes isosurface extractor,which is related filter generating isosurfaces from a structured point set,is provided to achieve sharp resolution for the simulation of non-diffusive interfacial flow.Compared with the traditional topology processing procedure,the current front tracking method is easier to be implemented and presents high performance in terms of computational resources.The numerical tests for 2-D highly-shearing flows and 3-D bubbles merging process are conducted to numerically examine the performance of the current methodology for tracking interfaces between two immiscible fluids.The Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) instability problems are successfully investigated with the present marching cubes based front tracking method.

  13. Designing a Clustering and Prediction-based Protocol for Target Tracking in Wireless Sensor Networks (WSNs

    Directory of Open Access Journals (Sweden)

    Vahid Hosseini

    2013-07-01

    Full Text Available Target tracking is one of the applications of wireless sensor network which is set up in the areas of field surveillance, habitat monitoring, and intruder tracking. Energy saving is one of the main challenges in target tracking sensor networks. In this paper, we present a Clustering and Prediction-Based Protocol (CPBP for Target Tracking in Wireless Sensor Networks (WSNs. Also, the Base Station (BS was exploited as a cluster formation manager and target movement predictor. Our protocol uses two parameters, distance and energy, for clustering algorithm. For evaluation, the proposed protocol was compared to a number of protocols in terms of network lifetime, number of transmitted packets and number of target miss during network lifetime. Performance of the proposed protocol was compared with cluster size 5 and 7. The simulation results represented desirable performance of the presented protocol.

  14. Relative discriminant coefficient based multi-cue fusion for robust object tracking

    Institute of Scientific and Technical Information of China (English)

    Jiangtao WANG; Jingyu YANG

    2008-01-01

    In visual tracking,integrating multiple cues will increase the reliability and robustness of the tracking system in situations where no single cue is reliable.In this paper,a novel multi-cue based tracking method is pre sented under the particle filter framework.Considering both practical distance and Bhattacharvva distance between particles and the target,a parameter called relative discriminant coefficient(RDC)is designed to measure the tracking ability for different features.Multi-cue fusion is carried out in a reweighing manner based on this parameter.Experimental results demonstrate the high robustness and effectiveness of our method in handling appearance changes,cluttered background,illumination changes and occlusions.

  15. Fault Detection Based on Tracking Differentiator Applied on the Suspension System of Maglev Train

    Directory of Open Access Journals (Sweden)

    Hehong Zhang

    2015-01-01

    Full Text Available A fault detection method based on the optimized tracking differentiator is introduced. It is applied on the acceleration sensor of the suspension system of maglev train. It detects the fault of the acceleration sensor by comparing the acceleration integral signal with the speed signal obtained by the optimized tracking differentiator. This paper optimizes the control variable when the states locate within or beyond the two-step reachable region to improve the performance of the approximate linear discrete tracking differentiator. Fault-tolerant control has been conducted by feedback based on the speed signal acquired from the optimized tracking differentiator when the acceleration sensor fails. The simulation and experiment results show the practical usefulness of the presented method.

  16. Detection and Tracking Strategies for Autonomous Aerial Refuelling Tasks Based on Monocular Vision

    Directory of Open Access Journals (Sweden)

    Yingjie Yin

    2014-07-01

    Full Text Available Detection and tracking strategies based on monocular vision are proposed for autonomous aerial refuelling tasks. The drogue attached to the fuel tanker aircraft has two important features. The grey values of the drogue's inner part are different from the external umbrella ribs, as shown in the image. The shape of the drogue's inner dark part is nearly circular. According to crucial prior knowledge, the rough and fine positioning algorithms are designed to detect the drogue. Particle filter based on the drogue's shape is proposed to track the drogue. A strategy to switch between detection and tracking is proposed to improve the robustness of the algorithms. The inner dark part of the drogue is segmented precisely in the detecting and tracking process and the segmented circular part can be used to measure its spatial position. The experimental results show that the proposed method has good performance in real-time and satisfied robustness and positioning accuracy.

  17. MULTI-LAYER TRACK FUSION ALGORITHM BASED ON SUPPORTING DEGREE MATRIX

    Institute of Scientific and Technical Information of China (English)

    Zhang Wei; Quan Li; Zhang Ke

    2012-01-01

    The random noises of multi-sensor and the environment make observations uncertain and correlative,so the performance of fusion algorithms is reduced by using observations directly.To solve this problem,a multi-layer track fusion algorithm based on supporting degree matrix is proposed.Combined with the track fusion algorithm based on filtering step by step,it uses multi-sensor observations to establish supporting degree matrix and realize multi-layer fusion.Simulation results show its estimation precision is higher than the original algorithm and is increased by 20% around.Therefore,it solves the problem of target tracking further in the distributed track fusion system.

  18. Observer-based linear parameter varying H∞ tracking control for hypersonic vehicles

    Directory of Open Access Journals (Sweden)

    Yiqing Huang

    2016-11-01

    Full Text Available This article aims to develop observer-based linear parameter varying output feedback H∞ tracking controller for hypersonic vehicles. Due to the complexity of an original nonlinear model of the hypersonic vehicle dynamics, a slow–fast loop linear parameter varying polytopic model is introduced for system stability analysis and controller design. Then, a state observer is developed by linear parameter varying technique in order to estimate the unmeasured attitude angular for slow loop system. Also, based on the designed linear parameter varying state observer, a kind of attitude tracking controller is presented to reduce tracking errors for all bounded reference attitude angular inputs. The closed-loop linear parameter varying system is proved to be quadratically stable by Lypapunov function technique. Finally, simulation results show that the developed linear parameter varying H∞ controller has good tracking capability for reference commands.

  19. Research of maneuvering target prediction and tracking technology based on IMM algorithm

    Science.gov (United States)

    Cao, Zheng; Mao, Yao; Deng, Chao; Liu, Qiong; Chen, Jing

    2016-09-01

    Maneuvering target prediction and tracking technology is widely used in both military and civilian applications, the study of those technologies is all along the hotspot and difficulty. In the Electro-Optical acquisition-tracking-pointing system (ATP), the primary traditional maneuvering targets are ballistic target, large aircraft and other big targets. Those targets have the features of fast velocity and a strong regular trajectory and Kalman Filtering and polynomial fitting have good effects when they are used to track those targets. In recent years, the small unmanned aerial vehicles developed rapidly for they are small, nimble and simple operation. The small unmanned aerial vehicles have strong maneuverability in the observation system of ATP although they are close-in, slow and small targets. Moreover, those vehicles are under the manual operation, therefore, the acceleration of them changes greatly and they move erratically. So the prediction and tracking precision is low when traditional algorithms are used to track the maneuvering fly of those targets, such as speeding up, turning, climbing and so on. The interacting multiple model algorithm (IMM) use multiple models to match target real movement trajectory, there are interactions between each model. The IMM algorithm can switch model based on a Markov chain to adapt to the change of target movement trajectory, so it is suitable to solve the prediction and tracking problems of the small unmanned aerial vehicles because of the better adaptability of irregular movement. This paper has set up model set of constant velocity model (CV), constant acceleration model (CA), constant turning model (CT) and current statistical model. And the results of simulating and analyzing the real movement trajectory data of the small unmanned aerial vehicles show that the prediction and tracking technology based on the interacting multiple model algorithm can get relatively lower tracking error and improve tracking precision

  20. Tracking method based on separation and combination of the measurements for radar and IR fusion system

    Institute of Scientific and Technical Information of China (English)

    Wang Qingchao; Wang Wenfei

    2009-01-01

    A new distributed fusion method of radar/infrared (IR) tracking system based on separation and combination of the measurements is proposed by analyzing the influence of rate measurement. The rate information separated from the radar measurements together with measurements of IR form a pseudo vector of IR, and the corresponding filter is designed. The results indicate that the method not only makes a great improvement to the local tracker's performance, but also improves the global tracking precision efficiently.

  1. A Low Cost Vision Based Hybrid Fiducial Mark Tracking Technique for Mobile Industrial Robots

    OpenAIRE

    Mohammed Y Aalsalem; Wazir Zada Khan; Quratul Ain Arshad

    2012-01-01

    The field of robotic vision is developing rapidly. Robots can react intelligently and provide assistance to user activities through sentient computing. Since industrial applications pose complex requirements that cannot be handled by humans, an efficient low cost and robust technique is required for the tracking of mobile industrial robots. The existing sensor based techniques for mobile robot tracking are expensive and complex to deploy, configure and maintain. Also some of them demand dedic...

  2. Trajectory Generation Model-Based IMM Tracking for Safe Driving in Intersection Scenario

    OpenAIRE

    2011-01-01

    Tracking the actions of vehicles at crossroads and planning safe trajectories will be an effective method to reduce the rate of traffic accident at intersections. It is to resolve the problem of the abrupt change because of the existence of drivers' voluntary choices. In this paper, we make approach of an improved IMM tracking method based on trajectory generation, abstracted by trajectory generation algorithm, to improve this situation. Because of the similarity between human-driving traject...

  3. Research on video target tracking technology based on improved SIFT algorithm

    Science.gov (United States)

    Zhuang, Zhemin; Guo, Zhijie; Yuang, Ye

    2017-01-01

    A novel target tracking algorithm based on improved SIFT (Scale Invariant Feature Transform (SIFT) algorithm is proposed in this paper. In order to improve real-time performance, the processing neighborhood of SIFT has been improved to decrease the complexity of calculation, and the dimension of the SIFT vector is set from 128 to 40. Simulations and experiments show this improved algorithm brings us low computation complexity and high tracking accuracy and robustness.

  4. Robotics Vision-based Heuristic Reasoning for Underwater Target Tracking and Navigation

    OpenAIRE

    Chua Kia; Mohd. Rizal Arshad

    2005-01-01

    This paper presents a robotics vision-based heuristic reasoning system for underwater target tracking and navigation. This system is introduced to improve the level of automation of underwater Remote Operated Vehicles (ROVs) operations. A prototype which combines computer vision with an underwater robotics system is successfully designed and developed to perform target tracking and intelligent navigation. This study focuses on developing image processing algorithms and fuzzy inference system ...

  5. Slow light based optical frequency shifter

    CERN Document Server

    Li, Qian; Thuresson, Axel; Nilsson, Adam N; Rippe, Lars; Kröll, Stefan

    2016-01-01

    We demonstrate experimentally and theoretically a controllable way of shifting the frequency of an optical pulse by using a combination of spectral hole burning, slow light effect, and linear Stark effect in a rare-earth-ion doped crystal. We claim that the solid angle of acceptance of a frequency shift structure can be close to $2\\pi$, which means that the frequency shifter could work not only for optical pulses propagating in a specific spatial mode but also for randomly scattered light. As the frequency shift is controlled solely by an external electric field, it works also for weak coherent light fields, and can e.g. be used as a frequency shifter for quantum memory devices in quantum communication.

  6. Online Deformable Object Tracking Based on Structure-Aware Hyper-Graph.

    Science.gov (United States)

    Du, Dawei; Qi, Honggang; Li, Wenbo; Wen, Longyin; Huang, Qingming; Lyu, Siwei

    2016-08-01

    Recent advances in online visual tracking focus on designing part-based model to handle the deformation and occlusion challenges. However, previous methods usually consider only the pairwise structural dependences of target parts in two consecutive frames rather than the higher order constraints in multiple frames, making them less effective in handling large deformation and occlusion challenges. This paper describes a new and efficient method for online deformable object tracking. Different from most existing methods, this paper exploits higher order structural dependences of different parts of the tracking target in multiple consecutive frames. We construct a structure-aware hyper-graph to capture such higher order dependences, and solve the tracking problem by searching dense subgraphs on it. Furthermore, we also describe a new evaluating data set for online deformable object tracking (the Deform-SOT data set), which includes 50 challenging sequences with full annotations that represent realistic tracking challenges, such as large deformations and severe occlusions. The experimental result of the proposed method shows considerable improvement in performance over the state-of-the-art tracking methods.

  7. Multitarget Tracking of Pedestrians in Video Sequences Based on Particle Filters

    Directory of Open Access Journals (Sweden)

    Hui Li

    2012-01-01

    Full Text Available Video target tracking is a critical problem in the field of computer vision. Particle filters have been proven to be very useful in target tracking for nonlinear and non-Gaussian estimation problems. Although most existing algorithms are able to track targets well in controlled environments, it is often difficult to achieve automated and robust tracking of pedestrians in video sequences if there are various changes in target appearance or surrounding illumination. To surmount these difficulties, this paper presents multitarget tracking of pedestrians in video sequences based on particle filters. In order to improve the efficiency and accuracy of the detection, the algorithm firstly obtains target regions in training frames by combining the methods of background subtraction and Histogram of Oriented Gradient (HOG and then establishes discriminative appearance model by generating patches and constructing codebooks using superpixel and Local Binary Pattern (LBP features in those target regions. During the process of tracking, the algorithm uses the similarity between candidates and codebooks as observation likelihood function and processes severe occlusion condition to prevent drift and loss phenomenon caused by target occlusion. Experimental results demonstrate that our algorithm improves the tracking performance in complicated real scenarios.

  8. Adaptive Robust Tracking Control of Pressure Trajectory Based on Kalman Filter

    Institute of Scientific and Technical Information of China (English)

    CAO Jian; ZHU Xiaocong; TAO Guoliang; YAO Bin

    2009-01-01

    When adaptive robust control(ARC) strategy based on backstepping design is applied in pneumatic servo control, accurate pressure tracking in motion is especially necessary for both force and position trajectories tracking of rodless pneumatic cylinders, and therefore an adaptive robust pressure controller is developed in this paper to improve the tracking accuracy of pressure trajectory in the chamber when the pneumatic cylinder is moving. In the proposed adaptive robust pressure controller, off-line fitting of the orifice area and on-line parameter estimation of the flow coefficient are utilized to have improved model compensation, and meanwhile robust feedback and Kalman filter are used to have strong robustness against uncertain nonlinearities, parameter fluctuations and noise. Research results demonstrate that the adaptive robust pressure controller could not only track various pressure trajectories accurately even when the pneumatic cylinder is moving, but also obtain very smooth control input, which indicates the effectiveness of adaptive model compensation. Especially when a step pressure trajectory is tracked under the condition of the movement of a rodless pneumatic cylinder, maximum tracking error of ARC is 4.46 kPa and average tracking error is 0.99 kPa, and steady-state error of ARC could achieve 0.84 kPa, which is very close to the measurement accuracy of pressure transducer.

  9. Microcontroller based resonance tracking unit for time resolved continuous wave cavity-ringdown spectroscopy measurements.

    Science.gov (United States)

    Votava, Ondrej; Mašát, Milan; Parker, Alexander E; Jain, Chaithania; Fittschen, Christa

    2012-04-01

    We present in this work a new tracking servoloop electronics for continuous wave cavity-ringdown absorption spectroscopy (cw-CRDS) and its application to time resolved cw-CRDS measurements by coupling the system with a pulsed laser photolysis set-up. The tracking unit significantly increases the repetition rate of the CRDS events and thus improves effective time resolution (and/or the signal-to-noise ratio) in kinetics studies with cw-CRDS in given data acquisition time. The tracking servoloop uses novel strategy to track the cavity resonances that result in a fast relocking (few ms) after the loss of tracking due to an external disturbance. The microcontroller based design is highly flexible and thus advanced tracking strategies are easy to implement by the firmware modification without the need to modify the hardware. We believe that the performance of many existing cw-CRDS experiments, not only time-resolved, can be improved with such tracking unit without any additional modification to the experiment. © 2012 American Institute of Physics

  10. Indoor Trajectory Tracking Scheme Based on Delaunay Triangulation and Heuristic Information in Wireless Sensor Networks.

    Science.gov (United States)

    Qin, Junping; Sun, Shiwen; Deng, Qingxu; Liu, Limin; Tian, Yonghong

    2017-06-02

    Object tracking and detection is one of the most significant research areas for wireless sensor networks. Existing indoor trajectory tracking schemes in wireless sensor networks are based on continuous localization and moving object data mining. Indoor trajectory tracking based on the received signal strength indicator (RSSI) has received increased attention because it has low cost and requires no special infrastructure. However, RSSI tracking introduces uncertainty because of the inaccuracies of measurement instruments and the irregularities (unstable, multipath, diffraction) of wireless signal transmissions in indoor environments. Heuristic information includes some key factors for trajectory tracking procedures. This paper proposes a novel trajectory tracking scheme based on Delaunay triangulation and heuristic information (TTDH). In this scheme, the entire field is divided into a series of triangular regions. The common side of adjacent triangular regions is regarded as a regional boundary. Our scheme detects heuristic information related to a moving object's trajectory, including boundaries and triangular regions. Then, the trajectory is formed by means of a dynamic time-warping position-fingerprint-matching algorithm with heuristic information constraints. Field experiments show that the average error distance of our scheme is less than 1.5 m, and that error does not accumulate among the regions.

  11. A Cost-Effective Tracking Algorithm for Hypersonic Glide Vehicle Maneuver Based on Modified Aerodynamic Model

    Directory of Open Access Journals (Sweden)

    Yu Fan

    2016-10-01

    Full Text Available In order to defend the hypersonic glide vehicle (HGV, a cost-effective single-model tracking algorithm using Cubature Kalman filter (CKF is proposed in this paper based on modified aerodynamic model (MAM as process equation and radar measurement model as measurement equation. In the existing aerodynamic model, the two control variables attack angle and bank angle cannot be measured by the existing radar equipment and their control laws cannot be known by defenders. To establish the process equation, the MAM for HGV tracking is proposed by using additive white noise to model the rates of change of the two control variables. For the ease of comparison several multiple model algorithms based on CKF are presented, including interacting multiple model (IMM algorithm, adaptive grid interacting multiple model (AGIMM algorithm and hybrid grid multiple model (HGMM algorithm. The performances of these algorithms are compared and analyzed according to the simulation results. The simulation results indicate that the proposed tracking algorithm based on modified aerodynamic model has the best tracking performance with the best accuracy and least computational cost among all tracking algorithms in this paper. The proposed algorithm is cost-effective for HGV tracking.

  12. Dynamic tracking of elementary preservice teachers' experiences with computer-based mathematics learning environments

    Science.gov (United States)

    Campbell, Stephen R.

    2003-05-01

    A challenging task in educational research today is to understand the implications of recent developments in computer-based learning environments. On the other hand, questions regarding learning and mathematical cognition have long been a central focus of research in mathematics education. Adding technology compounds an already complex problematic. Fortunately, computer-based technology also provides researchers with new ways of studying cognition and instruction. This paper introduces a new method for dynamically tracking learners' experiences in computer-based learning environments. Dynamic tracking is illustrated in both a classroom and a clinical setting by drawing on two studies with elementary preservice teachers working in computer-based mathematics learning environments.

  13. Tracking control of piezoelectric actuators using a polynomial-based hysteresis model

    Science.gov (United States)

    Gan, Jinqiang; Zhang, Xianmin; Wu, Heng

    2016-06-01

    A polynomial-based hysteresis model that describes hysteresis behavior in piezoelectric actuators is presented. The polynomial-based model is validated by comparing with the classic Prandtl-Ishlinskii model. Taking the advantages of the proposed model into consideration, inverse control using the polynomial-based model is proposed. To achieve better tracking performance, a hybrid control combining the developed inverse control and a proportional-integral-differential feedback loop is then proposed. To demonstrate the effectiveness of the proposed tracking controls, several comparative experiments of the polynomial-based model and Prandtl-Ishlinskii model are conducted. The experimental results show that inverse control and hybrid control using the polynomial-based model in trajectory-tracking applications are effective and meaningful.

  14. Light Particle Tracking Model for Simulating Bed Sediment Transport Load in River Areas

    Directory of Open Access Journals (Sweden)

    Israel E. Herrera-Díaz

    2017-01-01

    Full Text Available In this work a fast computational particles tracer model is developed based on Particle-In-Cell method to estimate the sediment transport in the access zone of a river port area. To apply the particles tracer method, first it is necessary to calculate the hydrodynamic fields of the study zone to determine the velocity fields in the three directions. The particle transport is governed mainly by the velocity fields and the turbulent dispersion. The mechanisms of dispersion and resuspension of particles are based in stochastic models, which describes the movement through a probability function. The developed code was validated using two well known cases with a discrete transformation obtaining a max relative error around 4.8% in both cases. The simulations were carried out with 350,000 particles allowing us to determine under certain circumstances different hydrodynamic scenarios where the zones are susceptible to present erosion and siltation at the entrance of the port.

  15. Part-based Pedestrian Detection and Feature-based Tracking for Driver Assistance

    DEFF Research Database (Denmark)

    Prioletti, Antonio; Møgelmose, Andreas; Grislieri, Paolo

    2013-01-01

    Detecting pedestrians is still a challenging task for automotive vision systems due to the extreme variability of targets, lighting conditions, occlusion, and high-speed vehicle motion. Much research has been focused on this problem in the last ten years and detectors based on classifiers have ga...

  16. Overall test evaluation based on trajectory tracking data

    Institute of Scientific and Technical Information of China (English)

    WANG; Zhengming; (

    2001-01-01

    [1]Morellim, E.A., Klein, V., Accuracy of aerodynamic model parameters estimated from flight test data, N19980048414/XAB, 1997.[2]Range Safety Group, Common risk criteria for national test ranges: Inert Debris, AD-A324 955/4/HDM,1997.[3] Williams, C.E., Comparison of circular error probable estimators for small samples, AD-A324 337/5/HDM, 1997.[4]Zhang, J.H., Spectrum analysis with its application in simulation, Journal of NUDT(in Chinese), 1998,(3): 1.[5] Andrese, J.A., Methodology for the analysis of obscurant attenuation effects on seeker target acquisition performance using modeling and simulation, AD-A353 726/XAB, 1998.[6]Wu, L.R., A Monte Carlo simulation of guidance accuracy evaluation, AD-A313 304/8/HDM, 1996.[7] Wang, Z.M., Yi, D.Y., Calibration and Evaluation on Trajectory Tracking Data(in Chinese), Changsha: NUDT Press, 1999, 367—374.[8] Wang, Z. M., Duan, X.J., Frequency domain method on separation of signal and noise, Science in China, Ser. E, 2000, 43(1): 9.[9]Wang, Z. M., Zhu, J. B., Reduced model on parameters of trajectory tracking data with its application,Science in China, Ser. E, 1999, 42(2): 190.[10]Zhang, J. H., Jia, P. R., Accuracy Analysis and Appraisal on Long-range Rocket(in Chinese), Changsha: NUDT Press, 1995, 27—64, 397—413.[11]James, O. B., Statistical Decision Theory and Bayesian Analysis, New York: Springer-Verlag, 1985, 215—230, 491—510.

  17. Qualifying lighting remodelling in a Hungarian city based on light pollution effects

    Science.gov (United States)

    Kolláth, Z.; Dömény, A.; Kolláth, K.; Nagy, B.

    2016-09-01

    The public lighting system has been remodelled in several Hungarian cities. In some cases the majority of the old luminaries were fitted with high pressure sodium lamps and they were replaced with white LED lighting with a typical correlated colour temperature of about 4500 K. Therefore, these remodelling works provide a testbed for methods in measurements and modelling. We measured the luminance of the light domes of selected cities by DSLR photometry before and after the remodelling. Thanks to the full cut off design of the new lighting fixtures we obtained a slight decrease even in the blue part of the sky dome spectra of a tested city. However, we have to note that this positive change is the result of the bad geometry (large ULR) of the previous lighting system. Based on Monte Carlo radiative transfer calculations we provide a comparison of different indicators that can be used to qualify the remodelling, and to predict the possible changes in light pollution.

  18. Enhanced Light Extraction from a GaN-based Light Emitting Diode with Triangle Grating Structure

    Directory of Open Access Journals (Sweden)

    Li Cheng

    2013-05-01

    Full Text Available We propose a simple method to improve the light extraction in GaN based light emitting diode. Conventional light emitting diode has an extraction limitation due to the total internal reflection which occurs at the interface between GaN and air. By using periodic grating etched at the GaN layer, we can couple more emitting light out of the active layer. Tapering the grating structure would facilitate the impedance matching between GaN light emitting diode and air, which can enhance broadband light extraction. We use finite difference time domain method to numerically find the best tapering grating structure. The numerical experiment demonstrate an enhance factor 4 of our proposed structure compared with the conventional one over broad band specctrum.

  19. Sliding mode output feedback control based on tracking error observer with disturbance estimator.

    Science.gov (United States)

    Xiao, Lingfei; Zhu, Yue

    2014-07-01

    For a class of systems who suffers from disturbances, an original output feedback sliding mode control method is presented based on a novel tracking error observer with disturbance estimator. The mathematical models of the systems are not required to be with high accuracy, and the disturbances can be vanishing or nonvanishing, while the bounds of disturbances are unknown. By constructing a differential sliding surface and employing reaching law approach, a sliding mode controller is obtained. On the basis of an extended disturbance estimator, a creative tracking error observer is produced. By using the observation of tracking error and the estimation of disturbance, the sliding mode controller is implementable. It is proved that the disturbance estimation error and tracking observation error are bounded, the sliding surface is reachable and the closed-loop system is robustly stable. The simulations on a servomotor positioning system and a five-degree-of-freedom active magnetic bearings system verify the effect of the proposed method.

  20. Time-driven Activity-based Cost of Fast-Track Total Hip and Knee Arthroplasty

    DEFF Research Database (Denmark)

    Andreasen, Signe E; Holm, Henriette B; Jørgensen, Mira

    2017-01-01

    this between 2 departments with different logistical set-ups. METHODS: Prospective data collection was analyzed using the time-driven activity-based costing method (TDABC) on time consumed by different staff members involved in patient treatment in the perioperative period of fast-track THA and TKA in 2 Danish...... orthopedic departments with standardized fast-track settings, but different logistical set-ups. RESULTS: Length of stay was median 2 days in both departments. TDABC revealed minor differences in the perioperative settings between departments, but the total cost excluding the prosthesis was similar at USD......-track methodology, the result could be a more cost-effective pathway altogether. As THA and TKA are potentially costly procedures and the numbers are increasing in an economical limited environment, the aim of this study is to present baseline detailed economical calculations of fast-track THA and TKA and compare...

  1. Commercial associative memory performance for applications in track-based triggers at the Large Hadron Collider

    Science.gov (United States)

    Webster, Jordan

    2017-01-01

    Dense track environments in pp collisions at the Large Hadron Collider (LHC) motivate the use of triggers with dedicated hardware for fast track reconstruction. The ATLAS Collaboration is in the process of implementing a Fast Tracker (FTK) trigger upgrade, in which Content Addressable Memories (CAMs) will be used to rapidly match hit patterns with large banks of simulated tracks. The FTK CAMs are produced primarily at the University of Pisa. However, commercial CAM technology is rapidly developing due to applications in computer networking devices. This poster presents new studies comparing FTK CAMs to cutting-edge ternary CAMs developed by Cavium. The comparison is intended to guide the design of future track-based trigger systems for the next Phase at the LHC.

  2. Tracking Positioning Algorithm for Direction of Arrival Based on Direction Lock Loop

    Directory of Open Access Journals (Sweden)

    Xiu-Zhi Cheng

    2015-06-01

    Full Text Available In order to solve the problem of poor real-time performance, low accuracy and high computational complexity in the traditional process of locating and tracking of Direction of Arrival (DOA of moving targets, this paper proposes a DOA algorithm based on the Direction Lock Loop (DILL which adopts Lock Loop structure to realize the estimation and location of DOA and can adjust the direction automatically along with the changes of a signal’s angular variation to track the position of the signal. Meanwhile, to reduce the influence of nonlinearity and noise on its performance, the UKF filter is designed for eliminating interference of the estimated target signal to improve accuracy of the signal tracking and stability of the system. Simulation results prove that the algorithm can not only get a high resolution DOA estimate signal, but can also locate and track multiple mobile targets effectively with enhanced accuracy, efficiency and stability.

  3. Kalman-Filter-Based Particle Tracking on Parallel Architectures at Hadron Colliders

    CERN Document Server

    Cerati, Giuseppe; Lantz, Steven; McDermott, Kevin; Riley, Dan; Tadel, Matevž; Wittich, Peter; Würthwein, Frank; Yagil, Avi

    2016-01-01

    Power density constraints are limiting the performance improvements of modern CPUs. To address this we have seen the introduction of lower-power, multi-core processors such as GPGPU, ARM and Intel MIC. To stay within the power density limits but still obtain Moore's Law performance/price gains, it will be necessary to parallelize algorithms to exploit larger numbers of lightweight cores and specialized functions like large vector units. Track finding and fitting is one of the most computationally challenging problems for event reconstruction in particle physics. At the High-Luminosity Large Hadron Collider (HL-LHC), for example, this will be by far the dominant problem. The need for greater parallelism has driven investigations of very different track finding techniques such as Cellular Automata or Hough Transforms. The most common track finding techniques in use today, however, are those based on the Kalman Filter. Significant experience has been accumulated with these techniques on real tracking detector sy...

  4. KARMA: Kalman-based autoregressive moving average modeling and inference for formant and antiformant tracking

    CERN Document Server

    Mehta, Daryush D; Wolfe, Patrick J

    2011-01-01

    Vocal tract resonance characteristics in acoustic speech signals are classically tracked using frame-by-frame point estimates of formant frequencies followed by candidate selection and smoothing using dynamic programming methods that minimize ad hoc cost functions. The goal of the current work is to provide both point estimates and associated uncertainties of center frequencies and bandwidths in a statistically principled state-space framework. Extended Kalman (K) algorithms take advantage of a linearized mapping to infer formant and antiformant parameters from frame-based estimates of autoregressive moving average (ARMA) cepstral coefficients. Error analysis of KARMA, WaveSurfer, and Praat is accomplished in the all-pole case using a manually marked formant database and synthesized speech waveforms. KARMA formant tracks exhibit lower overall root-mean-square error relative to the two benchmark algorithms, with third formant tracking more challenging. Antiformant tracking performance of KARMA is illustrated u...

  5. Research on regional intrusion prevention and control system based on target tracking

    Science.gov (United States)

    Liu, Yanfei; Wang, Jieling; Jiang, Ke; He, Yanhui; Wu, Zhilin

    2017-08-01

    In view of the fact that China’s border is very long and the border prevention and control measures are single, we designed a regional intrusion prevention and control system which based on target-tracking. The system consists of four parts: solar panel, radar, electro-optical equipment, unmanned aerial vehicle and intelligent tracking platform. The solar panel provides independent power for the entire system. The radar detects the target in real time and realizes the high precision positioning of suspicious targets, then through the linkage of electro-optical equipment, it can achieve full-time automatic precise tracking of targets. When the target appears within the range of detection, the drone will be launched to continue the tracking. The system is mainly to realize the full time, full coverage, whole process integration and active realtime control of the border area.

  6. Optimal Control Strategy for Marine Ssp Podded Propulsion Motor Based on Strong Tracking-Epf

    Directory of Open Access Journals (Sweden)

    Yao Wenlong

    2015-09-01

    Full Text Available Aiming at the non-linearity of state equation and observation equation of SSP (Siemen Schottel Propulsor propulsion motor, an improved particle filter algorithm based on strong tracking extent Kalman filter (ST-EKF was presented, and it was imported into the marine SSP propulsion motor control system. The strong tracking filter was used to update particles in the new algorithm and produce importance densities. As a result, the problems of particle degeneracy and sample impoverishment were ameliorated, the propulsion motor states and the rotor resistance were estimated simultaneously using strong track filter (STF, and the tracking ability of marine SSP propulsion motor control system was improved. Simulation result shown that the improved EPF algorithm was not only improving the prediction accuracy of the motor states and the rotor resistance, but also it can satisfy the requirement of navigation in harbor. It had the better accuracy than EPF algorithm.

  7. H∞ tracking control of coupled spatiotemporal chaos based on fuzzy models

    Institute of Scientific and Technical Information of China (English)

    Dou Chun-Xia

    2005-01-01

    Due to the interactions among coupled spatiotemporal subsystems, it is difficult to achieve the tracking control of the coupled spatiotemporal chaos. However, every subsystem of the coupled spatiotemporal chaos can be approximated by a set of fuzzy models, of which each represents a linearized model of the subsystem corresponding to the operating point of the controlled system. Based on these fuzzy models, an H∞ fuzzy tracking control scheme is suggested,where a linear matrix inequalities (LMI) is employed to represent the feedback controller. The parameters of controller are obtained by using convex optimization techniques of LMI. The model reference tracking control of the coupled spatiotemporal chaos is achieved, and the stability of the system is also guaranteed. The tracking performance is tested by simulation as an example.

  8. Model-Based Hand Tracking by Chamfer Distance and Adaptive Color Learning Using Particle Filter

    Directory of Open Access Journals (Sweden)

    Kerdvibulvech Chutisant

    2009-01-01

    Full Text Available We propose a new model-based hand tracking method for recovering of three-dimensional hand motion from an image sequence. We first build a three-dimensional hand model using truncated quadrics. The degrees of freedom (DOF for each joint correspond to the DOF of a real hand. This feature extraction is performed by using the Chamfer Distance function for the edge likelihood. The silhouette likelihood is performed by using a Bayesian classifier and the online adaptation of skin color probabilities. Therefore, it is to effectively deal with any illumination changes. Particle filtering is used to track the hand by predicting the next state of three-dimensional hand model. By using these techniques, this method adds the useful ability of automatic recovery from tracking failures. This method can also be used to track the guitarist's hand.

  9. Trajectory tracking control of underactuated USV based on modified backstepping approach

    Directory of Open Access Journals (Sweden)

    Dong Zaopeng

    2015-09-01

    Full Text Available This paper presents a state feedback based backstepping control algorithm to address the trajectory tracking problem of an underactuated Unmanned Surface Vessel (USV in the horizontal plane. A nonlinear three Degree of Freedom (DOF underactuated dynamic model for USV is considered, and trajectory tracking controller that can track both curve trajectory and straight line trajectory with high accuracy is designed as the well known Persistent Exciting (PE conditions of yaw velocity is completely relaxed in our study. The proposed controller has further been enriched by incorporating an integral action additionally for enhancing the steady state performance and control precision of the USV trajectory tracking control system. Global stability of the overall system is proved by Lyapunov theory and Barbalat’s Lemma, and then simulation experiments are carried out to demonstrate the effectiveness of the controller designed.

  10. Trajectory Generation Model-Based IMM Tracking for Safe Driving in Intersection Scenario

    Directory of Open Access Journals (Sweden)

    Tingting Zhou

    2011-01-01

    Full Text Available Tracking the actions of vehicles at crossroads and planning safe trajectories will be an effective method to reduce the rate of traffic accident at intersections. It is to resolve the problem of the abrupt change because of the existence of drivers' voluntary choices. In this paper, we make approach of an improved IMM tracking method based on trajectory generation, abstracted by trajectory generation algorithm, to improve this situation. Because of the similarity between human-driving trajectory and programming trajectory which is generated by trajectory-generated algorithm, the improved IMM method performs well in tracking moving vehicles with some sudden changes of its movement. A set of data is collected for experiments when an object vehicle takes a sudden left turn in intersection scenario. To compare the experiment results between IMM method with trajectory generation model and the one without, tracking error of the former decreases by 75% in particular scenario.

  11. Image-Based Multi-Target Tracking through Multi-Bernoulli Filtering with Interactive Likelihoods.

    Science.gov (United States)

    Hoak, Anthony; Medeiros, Henry; Povinelli, Richard J

    2017-03-03

    We develop an interactive likelihood (ILH) for sequential Monte Carlo (SMC) methods for image-based multiple target tracking applications. The purpose of the ILH is to improve tracking accuracy by reducing the need for data association. In addition, we integrate a recently developed deep neural network for pedestrian detection along with the ILH with a multi-Bernoulli filter. We evaluate the performance of the multi-Bernoulli filter with the ILH and the pedestrian detector in a number of publicly available datasets (2003 PETS INMOVE, Australian Rules Football League (AFL) and TUD-Stadtmitte) using standard, well-known multi-target tracking metrics (optimal sub-pattern assignment (OSPA) and classification of events, activities and relationships for multi-object trackers (CLEAR MOT)). In all datasets, the ILH term increases the tracking accuracy of the multi-Bernoulli filter.

  12. Image-Based Multi-Target Tracking through Multi-Bernoulli Filtering with Interactive Likelihoods

    Directory of Open Access Journals (Sweden)

    Anthony Hoak

    2017-03-01

    Full Text Available We develop an interactive likelihood (ILH for sequential Monte Carlo (SMC methods for image-based multiple target tracking applications. The purpose of the ILH is to improve tracking accuracy by reducing the need for data association. In addition, we integrate a recently developed deep neural network for pedestrian detection along with the ILH with a multi-Bernoulli filter. We evaluate the performance of the multi-Bernoulli filter with the ILH and the pedestrian detector in a number of publicly available datasets (2003 PETS INMOVE, Australian Rules Football League (AFL and TUD-Stadtmitte using standard, well-known multi-target tracking metrics (optimal sub-pattern assignment (OSPA and classification of events, activities and relationships for multi-object trackers (CLEAR MOT. In all datasets, the ILH term increases the tracking accuracy of the multi-Bernoulli filter.

  13. A comparison of vision-based tracking schemes for control of microbiorobots

    Science.gov (United States)

    Kim, Dal Hyung; Steager, Edward B.; Kei Cheang, U.; Byun, Doyoung; Kim, Min Jun

    2010-06-01

    There has been significant recent interest in micro-nano robots operating in low Reynold's number fluidic environments. Even though recent works showed the success of controlling micro-nano robots, there are some limitations because of the tracking method. In this paper, we introduce and implement a feature-based tracking method (FTM). Scale invariant feature transform (SIFT) is a well-explored technique at much larger length scales for research fields regarding robotics and vision. Here, the technique is extensively investigated and optimized for microbiorobots (MBRs) in low Reynold's number environments. Also, we compare the FTM with the conventional tracking method for cells, which is known as the region-based tracking method (RTM). We clearly show that the FTM can track more accurate positions of the objects in comparison with the RTM in cases where objects are in close contact or overlapped. Also, we demonstrate that the FTM allows tracking microscopic objects even though illumination changes over time or portions of the object are occluded or outside the field of view.

  14. A Low Cost Vision Based Hybrid Fiducial Mark Tracking Technique for Mobile Industrial Robots

    Directory of Open Access Journals (Sweden)

    Mohammed Y Aalsalem

    2012-07-01

    Full Text Available The field of robotic vision is developing rapidly. Robots can react intelligently and provide assistance to user activities through sentient computing. Since industrial applications pose complex requirements that cannot be handled by humans, an efficient low cost and robust technique is required for the tracking of mobile industrial robots. The existing sensor based techniques for mobile robot tracking are expensive and complex to deploy, configure and maintain. Also some of them demand dedicated and often expensive hardware. This paper presents a low cost vision based technique called “Hybrid Fiducial Mark Tracking” (HFMT technique for tracking mobile industrial robot. HFMT technique requires off-the-shelf hardware (CCD cameras and printable 2-D circular marks used as fiducials for tracking a mobile industrial robot on a pre-defined path. This proposed technique allows the robot to track on a predefined path by using fiducials for the detection of Right and Left turns on the path and White Strip for tracking the path. The HFMT technique is implemented and tested on an indoor mobile robot at our laboratory. Experimental results from robot navigating in real environments have confirmed that our approach is simple and robust and can be adopted in any hostile industrial environment where humans are unable to work.

  15. Observer-Based Adaptive Neural Network Trajectory Tracking Control for Remotely Operated Vehicle.

    Science.gov (United States)

    Chu, Zhenzhong; Zhu, Daqi; Yang, Simon X

    2017-07-01

    This paper focuses on the adaptive trajectory tracking control for a remotely operated vehicle (ROV) with an unknown dynamic model and the unmeasured states. Unlike most previous trajectory tracking control approaches, in this paper, the velocity states and the angular velocity states in the body-fixed frame are unmeasured, and the thrust model is inaccurate. Obviously, it is more in line with the actual ROV systems. Since the dynamic model is unknown, a new local recurrent neural network (local RNN) structure with fast learning speed is proposed for online identification. To estimate the unmeasured states, an adaptive terminal sliding-mode state observer based on the local RNN is proposed, so that the finite-time convergence of the trajectory tracking error can be guaranteed. Considering the problem of inaccurate thrust model, an adaptive scale factor is introduced into thrust model, and the thruster control signal is considered as the input of the trajectory tracking system directly. Based on the local RNN output, the adaptive scale factor, and the state estimation values, an adaptive trajectory tracking control law is constructed. The stability of the trajectory tracking control system is analyzed by the Lyapunov theorem. The effectiveness of the proposed control scheme is illustrated by simulations.

  16. Hardware-based Tracking at Trigger Level for ATLAS: The Fast TracKer (FTK) Project

    CERN Document Server

    Gramling, Johanna; The ATLAS collaboration

    2015-01-01

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

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

    CERN Document Server

    Gramling, Johanna; The ATLAS collaboration

    2015-01-01

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

  18. MMSE based Noise Tracking and Echo Cancellation of Speech Signals

    Directory of Open Access Journals (Sweden)

    Praveen. N

    2014-03-01

    Full Text Available During the recent years, there have been many studies on automatic audio classification and segmentation to use several features and techniques. The signal recorded at a microphone in a room incorporates the direct arrival of the sound from the source as well as the multiple weaker copies of the same signal that are created by sound reflections off the room walls. We call it as acoustic. Due to complications associated with exact tracking of the target in three dimensional environments, in many applications such as source localization and speech recognition the reverberate patterns imposed by the environment are seen as undesirable. In an auditorium, the common disturbances in public speech are Noise, Acoustic Echo etc. The MMSE estimator is one of the algorithms proposed for removal of additive background noise. It is a single channel speech enhancement technique for the enhancement of speech degraded by additive background noise. Background noise can effect our conversation in a noisy environment like in streets or in a car, when sending speech from the cockpit of an airplane to the ground or to the cabin and can effect both quality and intelligibility of speech. With the passage of time Spectral subtraction has undergone many modifications. This is a review paper and its objective is to provide an overview of MMSE estimator that has been proposed for enhancement of speech degraded by additive background noise during past decades

  19. Gaze Stripes: Image-Based Visualization of Eye Tracking Data.

    Science.gov (United States)

    Kurzhals, Kuno; Hlawatsch, Marcel; Heimerl, Florian; Burch, Michael; Ertl, Thomas; Weiskopf, Daniel

    2016-01-01

    We present a new visualization approach for displaying eye tracking data from multiple participants. We aim to show the spatio-temporal data of the gaze points in the context of the underlying image or video stimulus without occlusion. Our technique, denoted as gaze stripes, does not require the explicit definition of areas of interest but directly uses the image data around the gaze points, similar to thumbnails for images. A gaze stripe consists of a sequence of such gaze point images, oriented along a horizontal timeline. By displaying multiple aligned gaze stripes, it is possible to analyze and compare the viewing behavior of the participants over time. Since the analysis is carried out directly on the image data, expensive post-processing or manual annotation are not required. Therefore, not only patterns and outliers in the participants' scanpaths can be detected, but the context of the stimulus is available as well. Furthermore, our approach is especially well suited for dynamic stimuli due to the non-aggregated temporal mapping. Complementary views, i.e., markers, notes, screenshots, histograms, and results from automatic clustering, can be added to the visualization to display analysis results. We illustrate the usefulness of our technique on static and dynamic stimuli. Furthermore, we discuss the limitations and scalability of our approach in comparison to established visualization techniques.

  20. A Target Tracking Algorithm based on Fractional Ambiguity Function in Impulsive Noise Environment

    Directory of Open Access Journals (Sweden)

    Shi Xiaofei

    2016-01-01

    Full Text Available This paper proposes an airplane tracking algorithm based on study of the problem of interference localization. Firstly, a novel signal model to accurately estimate parameters of the airplane is proposed in impulsive noise environment. A method of instantaneous Doppler frequency estimation based on peak searching of the fractional lower-order ambiguity function based on the fractional Fourier transform (FLOS_FAF is proposed, and a method of projection approximation subspace tracking using robust m-estimation method based on fractional lower-order ambiguity function in fractional Fourier transform domain (FF-RLM_PAST is proposed to estimate the azimuth angle and elevation angle. As a result, the airplane tracking is achieved in bistatic radar, laying the foundations for interference localization. The correctness and effectiveness of the proposed method are verified with the computer simulation.

  1. Signal pulse emulation for scintillation detectors using Geant4 Monte Carlo with light tracking simulation

    Energy Technology Data Exchange (ETDEWEB)

    Ogawara, R. [Department of Medical Physics and Engineering, Graduate School of Medicine, Hokkaido University, Kita-15 Nishi-7, Kita-ku, Sapporo-shi, Hokkaido (Japan); Ishikawa, M., E-mail: masayori@med.hokudai.ac.jp [Graduate School of Health Science, Hokkaido University, Kita-12 Nishi-5, Kita-ku, Sapporo-shi, Hokkaido (Japan)

    2016-07-15

    The anode pulse of a photomultiplier tube (PMT) coupled with a scintillator is used for pulse shape discrimination (PSD) analysis. We have developed a novel emulation technique for the PMT anode pulse based on optical photon transport and a PMT response function. The photon transport was calculated using Geant4 Monte Carlo code and the response function with a BC408 organic scintillator. The obtained percentage RMS value of the difference between the measured and simulated pulse with suitable scintillation properties using GSO:Ce (0.4, 1.0, 1.5 mol%), LaBr{sub 3}:Ce and BGO scintillators were 2.41%, 2.58%, 2.16%, 2.01%, and 3.32%, respectively. The proposed technique demonstrates high reproducibility of the measured pulse and can be applied to simulation studies of various radiation measurements.

  2. Multimodal Detection of Music Performances for Intelligent Emotion Based Lighting

    DEFF Research Database (Denmark)

    Oxholm, Esben; Hansen, Ellen Kathrine; Triantafyllidis, Georgios

    2017-01-01

    . Using a microphone and a Kinect camera to detect such cues, the system is able to detect the intended emotion of what is being played. Specific lighting designs are then developed to support the specific emotions and the system is able to change between and alter the lighting design based...... on the incoming cues. The results suggest that the intelligent emotion-based lighting system has an advantage over a just beat synced lighting and it is concluded that there is reason to explore this idea further....

  3. Visible light metasurfaces based on gallium nitride high contrast gratings

    Science.gov (United States)

    Wang, Zhenhai; He, Shumin; Liu, Qifa; Wang, Wei

    2016-05-01

    We propose visible-light metasurfaces (VLMs) capable of serving as lens and beam deflecting element based on gallium nitride (GaN) high contrast gratings (HCGs). By precisely manipulating the wavefront of the transmitted light, we theoretically demonstrate an HCG focusing lens with transmissivity of 86.3%, and a VLM with beam deflection angle of 6.09° and transmissivity as high as 91.4%. The proposed all-dielectric metasurfaces are promising for GaN-based visible light-emitting diodes (LEDs), which would be robust and versatile for controlling the output light propagation and polarization, as well as enhancing the extraction efficiency of the LEDs.

  4. Tracking winter extra-tropical cyclones based on their relative vorticity evolution and sensitivity to prior data filtering (cycloTRACK v1.0

    Directory of Open Access Journals (Sweden)

    E. Flaounas

    2014-02-01

    Full Text Available In this study we present a new cyclone identification and tracking algorithm. Identification is based on a recognition pattern of enclosed contours of 850 hPa filtered relative vorticity values, while tracking is based on the minimization of a cost function. In particular, for each tracked cyclone our algorithm builds all possible tracks and finally chooses the one which presents the least differences of relative vorticity between consecutive track points. In parallel, for each track point the algorithm provides a cyclone area within which different physical diagnostics are calculated (such as pressure and wind speed. The area size is a function of the cyclone relative vorticity. To validate our approach we apply the algorithm on the Northern Hemisphere for the winters of 1989–2009. Three integrations of the algorithm were performed, each by using different filtering strengths. Using the three integrations, we assess the algorithm sensitivity to prior filtering the relative vorticity field. We show that filtering the input relative vorticity fields has an impact only on the weak cyclones, while in their majority the strong cyclones are independently detected and tracked.

  5. Novel tracking loop of BOC signal based on subcarrier tracking%基于副载波跟踪的BOC信号跟踪环路设计

    Institute of Scientific and Technical Information of China (English)

    杨再秀; 黄智刚; 耿生群

    2011-01-01

    针对二进制偏移载波(BOC,Binary Offset Carrier)调制信号跟踪的模糊性问题,提出了一种新的基于副载波跟踪的环路结构.通过增加副载波跟踪模块,对副载波和扩频码进行分离跟踪,解决了BOC信号跟踪的模糊性问题;针对副载波信号周期性的特点,以正弦波作为本地信号,利用锁相环实现对副载波的稳定跟踪.通过软件仿真,分析对比了该环路的码跟踪误差、跟踪门限和平均失锁时间(MTLL,Mean Time to Lose Lock)等性能指标.结果表明,新的环路结构能在保证跟踪精度的前提下,提高对弱信号的跟踪性能,具有较高的环路稳定性.%In order to eliminate the tracking ambiguity of binary offset carrier ( BOG ) signal, a novel tracking loop based on subcarrier tracking was proposed. Compared with traditional tracking loop, the proposed architecture provides a subcarrier locked loop to track subcarrier. The innovative tracking loop architecture resolves the tracking ambiguity problem by tracking the subcarrier and spread spectrum code respectively.The subcarrier was synchronized with the local sinusoidal signal using phase lock loop (PLL), which exploits the periodic feature of the subcarrier of BOC signal. Figures of merit, such as code tracking error, tracking threshold and mean time to lose lock (MTLL) have been analyzed and evaluated through software simulations.Simulation results show that the novel tracking loop can improve the tracking performance of weak signal and enhance the tracking loop stability with little degradation in tracking accuracy.

  6. Solar Automatic Tracking Double Fuzzy Control System Based on ARM%基于ARM的太阳自动跟踪双模糊控制系统

    Institute of Scientific and Technical Information of China (English)

    刘景艳; 李玉东; 杨晓邦

    2012-01-01

    针对太阳自动跟踪系统采用常规的PID控制器存在着跟踪精度低,超调量大等缺点,提出了一种基于ARM的太阳自动跟踪双模糊控制系统的设计方案;以32位ARM嵌入式微处理器为核心,采用光电跟踪和太阳运动轨迹跟踪相结合的混合跟踪模式;在光电跟踪模式下.采用模糊控制;在太阳运动轨迹跟踪模式下,采用模糊PID分段式控制,并依据光强的大小自动切换控制器;采用两个同样规格的太阳能电池板,分别采用固定安装和太阳自动跟踪系统测试太阳能电池板的采光强度;实验结果表明,该系统具有较高的跟踪精度,实现了对太阳全天候的跟踪,有效地提高了光电转换效率.%The solar automatic tracking system adopting the conventional PID controller has low tracking precision and big overshoot. The solar automatic tracking double fuzzy control system based on ARM is put forward. Embedded microcontroller 32-bit ARM processor is the core. A kind of mixed tracking mode is adopted, and it combines photoelectric tracking mode and solar trajectory tracking mode. The double fuzzy control method is presented, the fuzzy control method is adopted in photoelectric tracking mode, and in solar trajectory tracking mode, the fuzzy PID segmented tracking control method is put forward. And the controller can be automatically switched control mode according to light intensity. The fixed installation and the automatic tracking system are respectively used to test the solar panels daylighting strength. The experimental results show that the solar automatic tracking system is possessed of high tracking precision, realizes the sun round-the-clock tracking and effectively improves the photoelectric conversion efficiency.

  7. Real-Time Eye Detection and Tracking under Various Light Conditions

    Directory of Open Access Journals (Sweden)

    Feng Jiao

    2007-10-01

    Full Text Available This paper describes a real-time online prototype automobile and truck driver-fatigue monitor. It uses remotely located charge-coupled-device cameras equipped with active infrared illuminators to acquire video images of the driver. Various visual cues that typically characterize the level of alertness of a person are extracted in real time and systematically combined to infer the fatigue level of the driver. The visual cues employed characterize eyelid movement, gaze movement, head movement, and facial expression. A probabilistic model is developed to model human fatigue and to predict fatigue based on the visual cues obtained. The simultaneous use of multiple visual cues and their systematic combination yields a much more robust and accurate fatigue characterization than using a single visual cue. This system was validated under real-life fatigue conditions with human subjects of different ethnic backgrounds, genders, and ages; with/without glasses; and under different illumination conditions. It was found to be reasonably robust, reliable, and accurate in fatigue characterization.

  8. Efficiency and Privacy Enhancement for a Track and Trace System of RFID-Based Supply Chains

    Directory of Open Access Journals (Sweden)

    Xunjun Chen

    2015-06-01

    Full Text Available One of the major applications of Radio Frequency Identification (RFID technology is in supply chain management as it promises to provide real-time visibility based on the function of track and trace. However, such an RFID-based track and trace system raises new security and privacy challenges due to the restricted resource of tags. In this paper, we refine three privacy related models (i.e., the privacy, path unlinkability, and tag unlinkability of RFID-based track and trace systems, and clarify the relations among these privacy models. Specifically, we have proven that privacy is equivalent to path unlinkability and tag unlinkability implies privacy. Our results simplify the privacy concept and protocol design for RFID-based track and trace systems. Furthermore, we propose an efficient track and trace scheme, Tracker+, which allows for authentic and private identification of RFID-tagged objects in supply chains. In the Tracker+, no computational ability is required for tags, but only a few bytes of storage (such as EPC Class 1 Gen 2 tags are needed to store the tag state. Indeed, Tracker+ reduces the memory requirements for each tag by one group element compared to the Tracker presented in other literature. Moreover, Tracker+ provides privacy against supply chain inside attacks.

  9. 3D model-based detection and tracking for space autonomous and uncooperative rendezvous

    Science.gov (United States)

    Shang, Yang; Zhang, Yueqiang; Liu, Haibo

    2015-10-01

    In order to fully navigate using a vision sensor, a 3D edge model based detection and tracking technique was developed. Firstly, we proposed a target detection strategy over a sequence of several images from the 3D model to initialize the tracking. The overall purpose of such approach is to robustly match each image with the model views of the target. Thus we designed a line segment detection and matching method based on the multi-scale space technology. Experiments on real images showed that our method is highly robust under various image changes. Secondly, we proposed a method based on 3D particle filter (PF) coupled with M-estimation to track and estimate the pose of the target efficiently. In the proposed approach, a similarity observation model was designed according to a new distance function of line segments. Then, based on the tracking results of PF, the pose was optimized using M-estimation. Experiments indicated that the proposed method can effectively track and accurately estimate the pose of freely moving target in unconstrained environment.

  10. BLE-BASED ACCURATE INDOOR LOCATION TRACKING FOR HOME AND OFFICE

    Directory of Open Access Journals (Sweden)

    Joonghong Park

    2015-12-01

    Full Text Available Nowadays the use of smart mobile devices and the accompanying needs for emerging services relying on indoor location-based services (LBS for mobile devices are rapidly increasing. For more accurate location tracking using Bluetooth Low Energy (BLE, this paper proposes a novel trilateration-based algorithm and presents experimental results that demonstrate its effectiveness.

  11. TEDS Base Station Power Amplifier using Low-Noise Envelope Tracking Power Supply

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.

    2009-01-01

    This paper demonstrates a highly linear and efficient TETRA enhanced data service (TEDS) base-station RF power amplifier (RFPA). Based on the well-known combination of an envelope tracking (ET) power supply and a linear class-A/B RFPA, adequate adjacent channel power ratio (ACPR) and wideband noise...

  12. Data-driven pile-up correction for track-based analyses

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Holger; Lacker, Heiko; Leyton, Michael [HU Berlin (Germany); Brandt, Gerhard [University of Oxford (United Kingdom)

    2013-07-01

    The impact of pile-up can have considerable effects on observables measured at the LHC, especially those sensitive to the effects of the underlying event. We present a data-driven method that is based on the HBOM (''Hit Backspace Once More'') approach, to correct track-based distributions for tracks coming from pile-up interactions. We demonstrate successful application to a track-based measurement of event-shapes that are sensitive to the Underlying Event with the ATLAS detector. Tests of the method on Monte-Carlo simulation show closure within O(1-2 %) for the majority of bins of most observables studied.

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

    Directory of Open Access Journals (Sweden)

    Yao Zong Chen

    2016-01-01

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

  14. Online State-Based Structured SVM Combined With Incremental PCA for Robust Visual Tracking.

    Science.gov (United States)

    Yin, Yingjie; Xu, De; Wang, Xingang; Bai, Mingran

    2015-09-01

    In this paper, we propose a robust state-based structured support vector machine (SVM) tracking algorithm combined with incremental principal component analysis (PCA). Different from the current structured SVM for tracking, our method directly learns and predicts the object's states and not the 2-D translation transformation during tracking. We define the object's virtual state to combine the state-based structured SVM and incremental PCA. The virtual state is considered as the most confident state of the object in every frame. The incremental PCA is used to update the virtual feature vector corresponding to the virtual state and the principal subspace of the object's feature vectors. In order to improve the accuracy of the prediction, all the feature vectors are projected onto the principal subspace in the learning and prediction process of the state-based structured SVM. Experimental results on several challenging video sequences validate the effectiveness and robustness of our approach.

  15. Cluster-based centralized data fusion for tracking maneuvering targets using interacting multiple model algorithm

    Indian Academy of Sciences (India)

    V Vaidehi; K Kalavidya; S Indira Gandhi

    2004-04-01

    The interacting multiple model (IMM) algorithm has proved to be useful in tracking maneuvering targets. Tracking accuracy can be further improved using data fusion. Tracking of multiple targets using multiple sensors and fusing them at a central site using centralized architecture involves communication of large volumes of measurements to a common site. This results in heavy processing requirement at the central site. Moreover, track updates have to be obtained in the fusion centre before the next measurement arrives. For solving this computational complexity, a cluster-based parallel processing solution is presented in this paper. In this scheme, measurements are sent to the data fusion centre where the measurements are partitioned and given to the slave processors in the cluster. The slave processors use the IMM algorithm to get accurate updates of the tracks. The master processor collects the updated tracks and performs data fusion using ‘weight decision approach’. The improvement in the computation time using clusters in the data fusion centre is presented in this paper.

  16. Adaptive statistic tracking control based on two-step neural networks with time delays.

    Science.gov (United States)

    Yi, Yang; Guo, Lei; Wang, Hong

    2009-03-01

    This paper presents a new type of control framework for dynamical stochastic systems, called statistic tracking control (STC). The system considered is general and non-Gaussian and the tracking objective is the statistical information of a given target probability density function (pdf), rather than a deterministic signal. The control aims at making the statistical information of the output pdfs to follow those of a target pdf. For such a control framework, a variable structure adaptive tracking control strategy is first established using two-step neural network models. Following the B-spline neural network approximation to the integrated performance function, the concerned problem is transferred into the tracking of given weights. The dynamic neural network (DNN) is employed to identify the unknown nonlinear dynamics between the control input and the weights related to the integrated function. To achieve the required control objective, an adaptive controller based on the proposed DNN is developed so as to track a reference trajectory. Stability analysis for both the identification and tracking errors is developed via the use of Lyapunov stability criterion. Simulations are given to demonstrate the efficiency of the proposed approach.

  17. Robust motion tracking based on adaptive speckle decorrelation analysis of OCT signal.

    Science.gov (United States)

    Wang, Yuewen; Wang, Yahui; Akansu, Ali; Belfield, Kevin D; Hubbi, Basil; Liu, Xuan

    2015-11-01

    Speckle decorrelation analysis of optical coherence tomography (OCT) signal has been used in motion tracking. In our previous study, we demonstrated that cross-correlation coefficient (XCC) between Ascans had an explicit functional dependency on the magnitude of lateral displacement (δx). In this study, we evaluated the sensitivity of speckle motion tracking using the derivative of function XCC(δx) on variable δx. We demonstrated the magnitude of the derivative can be maximized. In other words, the sensitivity of OCT speckle tracking can be optimized by using signals with appropriate amount of decorrelation for XCC calculation. Based on this finding, we developed an adaptive speckle decorrelation analysis strategy to achieve motion tracking with optimized sensitivity. Briefly, we used subsequently acquired Ascans and Ascans obtained with larger time intervals to obtain multiple values of XCC and chose the XCC value that maximized motion tracking sensitivity for displacement calculation. Instantaneous motion speed can be calculated by dividing the obtained displacement with time interval between Ascans involved in XCC calculation. We implemented the above-described algorithm in real-time using graphic processing unit (GPU) and demonstrated its effectiveness in reconstructing distortion-free OCT images using data obtained from a manually scanned OCT probe. The adaptive speckle tracking method was validated in manually scanned OCT imaging, on phantom as well as in vivo skin tissue.

  18. Object Tracking Using Adaptive Covariance Descriptor and Clustering-Based Model Updating for Visual Surveillance

    Directory of Open Access Journals (Sweden)

    Lei Qin

    2014-05-01

    Full Text Available We propose a novel approach for tracking an arbitrary object in video sequences for visual surveillance. The first contribution of this work is an automatic feature extraction method that is able to extract compact discriminative features from a feature pool before computing the region covariance descriptor. As the feature extraction method is adaptive to a specific object of interest, we refer to the region covariance descriptor computed using the extracted features as the adaptive covariance descriptor. The second contribution is to propose a weakly supervised method for updating the object appearance model during tracking. The method performs a mean-shift clustering procedure among the tracking result samples accumulated during a period of time and selects a group of reliable samples for updating the object appearance model. As such, the object appearance model is kept up-to-date and is prevented from contamination even in case of tracking mistakes. We conducted comparing experiments on real-world video sequences, which confirmed the effectiveness of the proposed approaches. The tracking system that integrates the adaptive covariance descriptor and the clustering-based model updating method accomplished stable object tracking on challenging video sequences.

  19. An Improved Fast Compressive Tracking Algorithm Based on Online Random Forest Classifier

    Directory of Open Access Journals (Sweden)

    Xiong Jintao

    2016-01-01

    Full Text Available The fast compressive tracking (FCT algorithm is a simple and efficient algorithm, which is proposed in recent years. But, it is difficult to deal with the factors such as occlusion, appearance changes, pose variation, etc in processing. The reasons are that, Firstly, even if the naive Bayes classifier is fast in training, it is not robust concerning the noise. Secondly, the parameters are required to vary with the unique environment for accurate tracking. In this paper, we propose an improved fast compressive tracking algorithm based on online random forest (FCT-ORF for robust visual tracking. Firstly, we combine ideas with the adaptive compressive sensing theory regarding the weighted random projection to exploit both local and discriminative information of the object. The second reason is the online random forest classifier for online tracking which is demonstrated with more robust to the noise adaptively and high computational efficiency. The experimental results show that the algorithm we have proposed has a better performance in the field of occlusion, appearance changes, and pose variation than the fast compressive tracking algorithm’s contribution.

  20. Track reconstruction for the Mu3e experiment based on a novel Multiple Scattering fit

    Directory of Open Access Journals (Sweden)

    Kozlinskiy Alexandr

    2017-01-01

    Full Text Available The Mu3e experiment is designed to search for the lepton flavor violating decay μ+ → e+e+e−. The aim of the experiment is to reach a branching ratio sensitivity of 10−16. In a first phase the experiment will be performed at an existing beam line at the Paul-Scherrer Institute (Switzerland providing 108 muons per second, which will allow to reach a sensitivity of 2 · 10−15. The muons with a momentum of about 28 MeV/c are stopped and decay at rest on a target. The decay products (positrons and electrons with energies below 53MeV are measured by a tracking detector consisting of two double layers of 50 μm thin silicon pixel sensors. The high granularity of the pixel detector with a pixel size of 80 μm × 80 μm allows for a precise track reconstruction in the high multiplicity environment of the Mu3e experiment, reaching 100 tracks per reconstruction frame of 50 ns in the final phase of the experiment. To deal with such high rates and combinatorics, the Mu3e track reconstruction uses a novel fit algorithm that in the simplest case takes into account only the multiple scattering, which allows for a fast online tracking on a GPU based filter farm. An implementation of the 3-dimensional multiple scattering fit based on hit triplets is described. The extension of the fit that takes into account energy losses and pixel size is used for offline track reconstruction. The algorithm and performance of the offline track reconstruction based on a full Geant4 simulation of the Mu3e detector are presented.

  1. A vision-based material tracking system for heavy plate rolling mills

    Science.gov (United States)

    Tratnig, Mark; Reisinger, Johann; Hlobil, Helmut

    2007-01-01

    A modern heavy plate rolling mill can process more than 20 slabs and plates simultaneously. To avoid material confusions during a compact occupancy and the permanent discharging and re-entering of parts, one must know the identity and position of each part at every moment. One possibility to determine the identity and position of each slab and plate is the application of a comprehensive visual-based tracking system. Compared to a tracking system that calculates the position of a plate based on the diameter and the turns of the transport rolls, a visual system is not corrupted by a position- and material dependent transmission slip. In this paper we therefore present a vision-based material tracking system for the 2-dimensional tracking of glowing material in harsh environment. It covers the production area from the plant's descaler to the pre-stand of the rolling mill and consists of four independent, synchronized overlapping cameras. The paper first presents the conceptual design of the tracking system - and continues then with the camera calibration, the determination of pixel contours, the data segmentation and the fitting & modelling of the objects bodies. In a next step, the work will then show the testing setup. It will be described how the material tracking system was implemented into the control system of the rolling mill and how the delivered tracking data was checked on its correctness. Finally, the paper presents some results. It will be shown that the position of some moving plates was estimated with a precision of approx. 0.5m. The results will be analyzed and it will be explained where the inaccuracies come from and how they eventually can be removed. The paper ends with a conclusion and an outlook on future work.

  2. Developing Quantum Dot Phosphor-Based Light-Emitting Diodes for Aviation Lighting Applications

    Directory of Open Access Journals (Sweden)

    Fengbing Wu

    2012-01-01

    Full Text Available We have investigated the feasibility of employing quantum dot (QD phosphor-based light-emitting diodes (LEDs in aviation applications that request Night Vision Imaging Systems (NVIS compliance. Our studies suggest that the emerging QD phosphor-based LED technology could potentially be superior to conventional aviation lighting technology by virtue of the marriage of tight spectral control and broad wavelength tunability. This largely arises from the fact that the optical properties of semiconductor nanocrystal QDs can be tailored by varying the nanocrystal size without any compositional changes. It is envisioned that the QD phosphor-based LEDs hold great potentials in cockpit illumination, back light sources of monitor screens, as well as the LED indicator lights of aviation panels.

  3. A self-recalibration method based on scale-invariant registration for structured light measurement systems

    Science.gov (United States)

    Chen, Rui; Xu, Jing; Zhang, Song; Chen, Heping; Guan, Yong; Chen, Ken

    2017-01-01

    The accuracy of structured light measurement depends on delicate offline calibration. However, in some practical applications, the system is supposed to be reconfigured so frequently to track the target that an online calibration is required. To this end, this paper proposes a rapid and autonomous self-recalibration method. For the proposed method, first, the rotation matrix and the normalized translation vector are attained from the fundamental matrix; second, the scale factor is acquired based on scale-invariant registration such that the actual translation vector is obtained. Experiments have been conducted to verify the effectiveness of our proposed method and the results indicate a high degree of accuracy.

  4. A novel method for estimating the track-soil parameters based on Kalman and improved strong tracking filters.

    Science.gov (United States)

    Yao, Yu; Cheng, Kai; Zhou, Zhi-Jie; Zhang, Bang-Cheng; Dong, Chao; Zheng, Sen

    2015-11-01

    A tracked vehicle has been widely used in exploring unknown environments and military fields. In current methods for suiting soil conditions, soil parameters need to be given and the traction performance cannot always be satisfied on soft soil. To solve the problem, it is essential to estimate track-soil parameters in real-time. Therefore, a detailed mathematical model is proposed for the first time. Furthermore, a novel algorithm which is composed of Kalman filter (KF) and improved strong tracking filter (STF) is developed for online track-soil estimation and named as KF-ISTF. By this method, the KF is used to estimate slip parameters, and the ISTF is used to estimate motion states. Then the key soil parameters can be estimated by using a suitable soil model. The experimental results show that equipped with the estimation algorithm, the proposed model can be used to estimate the track-soil parameters, and make the traction performance satisfied with soil conditions.

  5. A Tracking-Based Target Locating Algorithm in Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    SUN Xue-bin; ZHOU Zheng

    2004-01-01

    This paper proposes a tracking-based target locating algorithm to locate a target moving in a geographical region under the surveillance of a wireless sensor network. This algorithm first finds a sensor node that has detected the target, and then uses local messages between neighboring nodes to track the trail of the target. The authors implement this algorithm and compare it with an optimized flood-based target locating algorithm. Simulation results show that this algorithm effectively reduces the message transmission, conserves energy and consequently enhances the practicability of resource-limited wireless sensor networks.

  6. Object Detection and Tracking-Based Camera Calibration for Normalized Human Height Estimation

    Directory of Open Access Journals (Sweden)

    Jaehoon Jung

    2016-01-01

    Full Text Available This paper presents a normalized human height estimation algorithm using an uncalibrated camera. To estimate the normalized human height, the proposed algorithm detects a moving object and performs tracking-based automatic camera calibration. The proposed method consists of three steps: (i moving human detection and tracking, (ii automatic camera calibration, and (iii human height estimation and error correction. The proposed method automatically calibrates camera by detecting moving humans and estimates the human height using error correction. The proposed method can be applied to object-based video surveillance systems and digital forensic.

  7. A MEMS-based Adaptive AHRS for Marine Satellite Tracking Antenna

    DEFF Research Database (Denmark)

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

    2015-01-01

    Satellite tracking is a challenging task for marine applications. An attitude determination system should estimate the wave disturbances on the ship body accurately. To achieve this, an Attitude Heading Reference System (AHRS) based on Micro-Electro-Mechanical Systems (MEMS) sensors, composed...... of three-axis gyroscope, accelerometer and magnetometer, is developed for Marine Satellite Tracking Antenna (MSTA). In this paper, the attitude determination algorithm is improved using an adaptive mechanism that tunes the attitude estimator parameters based on an estimation of ship motion frequency...

  8. Structured-light Image Compression Based on Fractal Theory

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The method of fractal image compression is introduced which is applied to compress the line structured-light image. Based on the self-similarity of the structured-light image, we attain satisfactory compression ratio and higher peak signal-to-noise ratio (PSNR). The experimental results indicate that this method can achieve high performance.

  9. Phase Noise Squeezing Based Parametric Bifurcation Tracking of MIP-Coated Microbeam MEMS Sensor for TNT Explosive Gas Sensing

    Science.gov (United States)

    2014-06-08

    Based Parametric Bifurcation Tracking of Mip -Coated Microbeam MEMS Sensor for TNT Explosive Gas Sensing See Attached The views, opinions and/or...2050 1 ABSTRACT Phase Noise-Squeezing-Based Parametric Bifurcation Tracking of Mip -Coated Microbeam MEMS Sensor for TNT Explosive Gas Sensing...SQUEEZING BASED PARAMETRIC BIFURCATION TRACKING OF MIP -COATED MICROBEAM MEMS SENSOR FOR TNT EXPLOSIVE GAS SENSING L. L. Li1*, E. L. Holthoff2, L. A

  10. Gold Standard Testing of Motion Based Tracking Systems

    Science.gov (United States)

    2017-03-15

    patented invention that may relate to them. This report was cleared for public release by the 88th Air Base Wing Public Affairs Office and is available...systems against a ‘Gold Standard’ on-field measurement system for human physiological performance monitoring. Data shows that the accuracy of the...Zebra (RFID-based) system is very good, due to its high sampling frequency, with most measurements being within ~2% for distance and ~4% for velocity

  11. A Quantitative Analysis on Two RFS-Based Filtering Methods for Multicell Tracking

    Directory of Open Access Journals (Sweden)

    Yayun Ren

    2014-01-01

    Full Text Available Multiobject filters developed from the theory of random finite sets (RFS have recently become well-known methods for solving multiobject tracking problem. In this paper, we present two RFS-based filtering methods, Gaussian mixture probability hypothesis density (GM-PHD filter and multi-Bernoulli filter, to quantitatively analyze their performance on tracking multiple cells in a series of low-contrast image sequences. The GM-PHD filter, under linear Gaussian assumptions on the cell dynamics and birth process, applies the PHD recursion to propagate the posterior intensity in an analytic form, while the multi-Bernoulli filter estimates the multitarget posterior density through propagating the parameters of a multi-Bernoulli RFS that approximates the posterior density of multitarget RFS. Numerous performance comparisons between the two RFS-based methods are carried out on two real cell images sequences and demonstrate that both yield satisfactory results that are in good agreement with manual tracking method.

  12. Towards 3D ultrasound image based soft tissue tracking: a transrectal ultrasound prostate image alignment system

    CERN Document Server

    Baumann, Michael; Daanen, Vincent; Troccaz, Jocelyne

    2007-01-01

    The emergence of real-time 3D ultrasound (US) makes it possible to consider image-based tracking of subcutaneous soft tissue targets for computer guided diagnosis and therapy. We propose a 3D transrectal US based tracking system for precise prostate biopsy sample localisation. The aim is to improve sample distribution, to enable targeting of unsampled regions for repeated biopsies, and to make post-interventional quality controls possible. Since the patient is not immobilized, since the prostate is mobile and due to the fact that probe movements are only constrained by the rectum during biopsy acquisition, the tracking system must be able to estimate rigid transformations that are beyond the capture range of common image similarity measures. We propose a fast and robust multi-resolution attribute-vector registration approach that combines global and local optimization methods to solve this problem. Global optimization is performed on a probe movement model that reduces the dimensionality of the search space a...

  13. Lidar-based wake tracking for closed-loop wind farm control

    Science.gov (United States)

    Raach, Steffen; Schlipf, David; Cheng, Po Wen

    2016-09-01

    This work presents two advancements towards closed-loop wake redirecting of a wind turbine. First, a model-based estimation approach is presented which uses a nacelle-based lidar system facing downwind to obtain information about the wake. A reduced order wake model is described which is then used in the estimation to track the wake. The tracking is demonstrated with lidar measurement data from an offshore campaign and with simulated lidar data from a SOWFA simulation. Second, a controller for closed-loop wake steering is presented. It uses the wake tracking information to set the yaw actuator of the wind turbine to redirect the wake to a desired position. Altogether, this paper aims to present the concept of closed-loop wake redirecting and gives a possible solution to it.

  14. Accurate mask-based spatially regularized correlation filter for visual tracking

    Science.gov (United States)

    Gu, Xiaodong; Xu, Xinping

    2017-01-01

    Recently, discriminative correlation filter (DCF)-based trackers have achieved extremely successful results in many competitions and benchmarks. These methods utilize a periodic assumption of the training samples to efficiently learn a classifier. However, this assumption will produce unwanted boundary effects, which severely degrade the tracking performance. Correlation filters with limited boundaries and spatially regularized DCFs were proposed to reduce boundary effects. However, their methods used the fixed mask or predesigned weights function, respectively, which was unsuitable for large appearance variation. We propose an accurate mask-based spatially regularized correlation filter for visual tracking. Our augmented objective can reduce the boundary effect even in large appearance variation. In our algorithm, the masking matrix is converted into the regularized function that acts on the correlation filter in frequency domain, which makes the algorithm fast convergence. Our online tracking algorithm performs favorably against state-of-the-art trackers on OTB-2015 Benchmark in terms of efficiency, accuracy, and robustness.

  15. An Efficient Lagrangean Relaxation-based Object Tracking Algorithm in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Frank Yeong-Sung Lin

    2010-08-01

    Full Text Available In this paper we propose an energy-efficient object tracking algorithm in wireless sensor networks (WSNs. Such sensor networks have to be designed to achieve energy-efficient object tracking for any given arbitrary topology. We consider in particular the bi-directional moving objects with given frequencies for each pair of sensor nodes and link transmission cost. This problem is formulated as a 0/1 integer-programming problem. A Lagrangean relaxation-based (LR-based heuristic algorithm is proposed for solving the optimization problem. Experimental results showed that the proposed algorithm achieves near optimization in energy-efficient object tracking. Furthermore, the algorithm is very efficient and scalable in terms of the solution time.

  16. Fuzzy Neural Network-Based Interacting Multiple Model for Multi-Node Target Tracking Algorithm

    Directory of Open Access Journals (Sweden)

    Baoliang Sun

    2016-11-01

    Full Text Available An interacting multiple model for multi-node target tracking algorithm was proposed based on a fuzzy neural network (FNN to solve the multi-node target tracking problem of wireless sensor networks (WSNs. Measured error variance was adaptively adjusted during the multiple model interacting output stage using the difference between the theoretical and estimated values of the measured error covariance matrix. The FNN fusion system was established during multi-node fusion to integrate with the target state estimated data from different nodes and consequently obtain network target state estimation. The feasibility of the algorithm was verified based on a network of nine detection nodes. Experimental results indicated that the proposed algorithm could trace the maneuvering target effectively under sensor failure and unknown system measurement errors. The proposed algorithm exhibited great practicability in the multi-node target tracking of WSNs.

  17. Remote Control of an Autonomous Robotic Platform Based on Eye Tracking

    Directory of Open Access Journals (Sweden)

    PASARICA, A.

    2016-11-01

    Full Text Available Eye-tracking devices are currently used for improving communication and psychosocial status among patients with neuro-motor disabilities. This paper presents the experimental implementation of a control system for a robotic platform using eye tracking technology. The main system is based on an eye tracking subsystem that uses the circular Hough transform algorithm. A central processing unit performs the data transmission between the user and the robotic platform. Experimental tests were conducted to determine the device's performances and usability for patients with neuro-motor disabilities. Moreover, the test results were used to determine the control system learning curve. We created a data base containing information on the robotic platform processing time and precision of movement for improving the platform's performances.

  18. High Resolution Tracking Devices Based on Capillaries Filled with Liquid Scintillator

    CERN Multimedia

    Bonekamper, D; Vassiltchenko, V; Wolff, T

    2002-01-01

    %RD46 %title\\\\ \\\\The aim of the project is to develop high resolution tracking devices based on thin glass capillary arrays filled with liquid scintillator. This technique provides high hit densities and a position resolution better than 20 $\\mu$m. Further, their radiation hardness makes them superior to other types of tracking devices with comparable performance. Therefore, the technique is attractive for inner tracking in collider experiments, microvertex devices, or active targets for short-lived particle detection. High integration levels in the read-out based on the use of multi-pixel photon detectors and the possibility of optical multiplexing allow to reduce considerably the number of output channels, and, thus, the cost for the detector.\\\\ \\\\New optoelectronic devices have been developed and tested: the megapixel Electron Bombarded CCD (EBCCD), a high resolution image-detector having an outstanding capability of single photo-electron detection; the Vacuum Image Pipeline (VIP), a high-speed gateable pi...

  19. Hardware-based Tracking at Trigger Level for ATLAS the Fast TracKer (FTK) Project

    CERN Document Server

    INSPIRE-00245767

    2015-01-01

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

  20. Endoscopic vision-based tracking of multiple surgical instruments during robot-assisted surgery.

    Science.gov (United States)

    Ryu, Jiwon; Choi, Jaesoon; Kim, Hee Chan

    2013-01-01

    Robot-assisted minimally invasive surgery is effective for operations in limited space. Enhancing safety based on automatic tracking of surgical instrument position to prevent inadvertent harmful events such as tissue perforation or instrument collisions could be a meaningful augmentation to current robotic surgical systems. A vision-based instrument tracking scheme as a core algorithm to implement such functions was developed in this study. An automatic tracking scheme is proposed as a chain of computer vision techniques, including classification of metallic properties using k-means clustering and instrument movement tracking using similarity measures, Euclidean distance calculations, and a Kalman filter algorithm. The implemented system showed satisfactory performance in tests using actual robot-assisted surgery videos. Trajectory comparisons of automatically detected data and ground truth data obtained by manually locating the center of mass of each instrument were used to quantitatively validate the system. Instruments and collisions could be well tracked through the proposed methods. The developed collision warning system could provide valuable information to clinicians for safer procedures.

  1. Parallelized Kalman-Filter-Based Reconstruction of Particle Tracks on Many-Core Processors and GPUs

    Science.gov (United States)

    Cerati, Giuseppe; Elmer, Peter; Krutelyov, Slava; Lantz, Steven; Lefebvre, Matthieu; Masciovecchio, Mario; McDermott, Kevin; Riley, Daniel; Tadel, Matevž; Wittich, Peter; Würthwein, Frank; Yagil, Avi

    2017-08-01

    For over a decade now, physical and energy constraints have limited clock speed improvements in commodity microprocessors. Instead, chipmakers have been pushed into producing lower-power, multi-core processors such as Graphical Processing Units (GPU), ARM CPUs, and Intel MICs. Broad-based efforts from manufacturers and developers have been devoted to making these processors user-friendly enough to perform general computations. However, extracting performance from a larger number of cores, as well as specialized vector or SIMD units, requires special care in algorithm design and code optimization. One of the most computationally challenging problems in high-energy particle experiments is finding and fitting the charged-particle tracks during event reconstruction. This is expected to become by far the dominant problem at the High-Luminosity Large Hadron Collider (HL-LHC), for example. Today the most common track finding methods are those based on the Kalman filter. Experience with Kalman techniques on real tracking detector systems has shown that they are robust and provide high physics performance. This is why they are currently in use at the LHC, both in the trigger and offine. Previously we reported on the significant parallel speedups that resulted from our investigations to adapt Kalman filters to track fitting and track building on Intel Xeon and Xeon Phi. Here, we discuss our progresses toward the understanding of these processors and the new developments to port the Kalman filter to NVIDIA GPUs.

  2. Feature selection for appearance-based vehicle tracking in geospatial video

    Science.gov (United States)

    Poostchi, Mahdieh; Bunyak, Filiz; Palaniappan, Kannappan; Seetharaman, Guna

    2013-05-01

    Current video tracking systems often employ a rich set of intensity, edge, texture, shape and object level features combined with descriptors for appearance modeling. This approach increases tracker robustness but is compu- tationally expensive for realtime applications and localization accuracy can be adversely affected by including distracting features in the feature fusion or object classification processes. This paper explores offline feature subset selection using a filter-based evaluation approach for video tracking to reduce the dimensionality of the feature space and to discover relevant representative lower dimensional subspaces for online tracking. We com- pare the performance of the exhaustive FOCUS algorithm to the sequential heuristic SFFS, SFS and RELIEF feature selection methods. Experiments show that using offline feature selection reduces computational complex- ity, improves feature fusion and is expected to translate into better online tracking performance. Overall SFFS and SFS perform very well, close to the optimum determined by FOCUS, but RELIEF does not work as well for feature selection in the context of appearance-based object tracking.

  3. A System based on Adaptive Background Subtraction Approach for Moving Object Detection and Tracking in Videos

    Directory of Open Access Journals (Sweden)

    Bahadır KARASULU

    2013-04-01

    Full Text Available Video surveillance systems are based on video and image processing research areas in the scope of computer science. Video processing covers various methods which are used to browse the changes in existing scene for specific video. Nowadays, video processing is one of the important areas of computer science. Two-dimensional videos are used to apply various segmentation and object detection and tracking processes which exists in multimedia content-based indexing, information retrieval, visual and distributed cross-camera surveillance systems, people tracking, traffic tracking and similar applications. Background subtraction (BS approach is a frequently used method for moving object detection and tracking. In the literature, there exist similar methods for this issue. In this research study, it is proposed to provide a more efficient method which is an addition to existing methods. According to model which is produced by using adaptive background subtraction (ABS, an object detection and tracking system’s software is implemented in computer environment. The performance of developed system is tested via experimental works with related video datasets. The experimental results and discussion are given in the study

  4. Parallelized Kalman-Filter-Based Reconstruction of Particle Tracks on Many-Core Processors and GPUs

    Directory of Open Access Journals (Sweden)

    Cerati Giuseppe

    2017-01-01

    Full Text Available For over a decade now, physical and energy constraints have limited clock speed improvements in commodity microprocessors. Instead, chipmakers have been pushed into producing lower-power, multi-core processors such as Graphical Processing Units (GPU, ARM CPUs, and Intel MICs. Broad-based efforts from manufacturers and developers have been devoted to making these processors user-friendly enough to perform general computations. However, extracting performance from a larger number of cores, as well as specialized vector or SIMD units, requires special care in algorithm design and code optimization. One of the most computationally challenging problems in high-energy particle experiments is finding and fitting the charged-particle tracks during event reconstruction. This is expected to become by far the dominant problem at the High-Luminosity Large Hadron Collider (HL-LHC, for example. Today the most common track finding methods are those based on the Kalman filter. Experience with Kalman techniques on real tracking detector systems has shown that they are robust and provide high physics performance. This is why they are currently in use at the LHC, both in the trigger and offine. Previously we reported on the significant parallel speedups that resulted from our investigations to adapt Kalman filters to track fitting and track building on Intel Xeon and Xeon Phi. Here, we discuss our progresses toward the understanding of these processors and the new developments to port the Kalman filter to NVIDIA GPUs.

  5. Developing smart lighting LED-based device by using light parameterization and control method

    Science.gov (United States)

    Risteiu, Mircea; Ileana, Ioan; Marc, Gheorghe

    2016-12-01

    The paper presents a smart system for control of chromatic distribution of white light produced by LED sources in order to satisfy simultaneously physiological comfort and color rendering requests. In region of interest (ROI) lighted by an ensemble of RGB and white LED's, a system of appropriate light sensors (from UV to IR radiation) take the chromatic an intensity information and send them to a microcontroller based device. Following the actual state of illumination end the desired one, the microcontroller will command the LED drivers adequately to obtain the optimum situation.

  6. 3D model-based catheter tracking for motion compensation in EP procedures

    Science.gov (United States)

    Brost, Alexander; Liao, Rui; Hornegger, Joachim; Strobel, Norbert

    2010-02-01

    Atrial fibrillation is the most common sustained heart arrhythmia and a leading cause of stroke. Its treatment by radio-frequency catheter ablation, performed using fluoroscopic image guidance, is gaining increasingly more importance. Two-dimensional fluoroscopic navigation can take advantage of overlay images derived from pre-operative 3-D data to add anatomical details otherwise not visible under X-ray. Unfortunately, respiratory motion may impair the utility of these static overlay images for catheter navigation. We developed an approach for image-based 3-D motion compensation as a solution to this problem. A bi-plane C-arm system is used to take X-ray images of a special circumferential mapping catheter from two directions. In the first step of the method, a 3-D model of the device is reconstructed. Three-dimensional respiratory motion at the site of ablation is then estimated by tracking the reconstructed catheter model in 3-D. This step involves bi-plane fluoroscopy and 2-D/3-D registration. Phantom data and clinical data were used to assess our model-based catheter tracking method. Experiments involving a moving heart phantom yielded an average 2-D tracking error of 1.4 mm and an average 3-D tracking error of 1.1 mm. Our evaluation of clinical data sets comprised 469 bi-plane fluoroscopy frames (938 monoplane fluoroscopy frames). We observed an average 2-D tracking error of 1.0 mm +/- 0.4 mm and an average 3-D tracking error of 0.8 mm +/- 0.5 mm. These results demonstrate that model-based motion-compensation based on 2-D/3-D registration is both feasible and accurate.

  7. Distributed Information Compression for Target Tracking in Cluster-Based Wireless Sensor Networks.

    Science.gov (United States)

    Liao, Shi-Kuan; Lai, Kai-Jay; Tsai, Hsiao-Ping; Wen, Chih-Yu

    2016-06-22

    Target tracking is a critical wireless sensor application, which involves signal and information processing technologies. In conventional target position estimation methods, an estimate is usually demonstrated by an average target position. In contrast, this work proposes a distributed information compression method to describe the measurement uncertainty of tracking problems in cluster-based wireless sensor networks. The leader-based information processing scheme is applied to perform target positioning and energy conservation. A two-level hierarchical network topology is adopted for energy-efficient target tracking with information compression. A Level 1 network architecture is a cluster-based network topology for managing network operations. A Level 2 network architecture is an event-based and leader-based topology, utilizing the concept of information compression to process the estimates of sensor nodes. The simulation results show that compared to conventional schemes, the proposed data processing scheme has a balanced system performance in terms of tracking accuracy, data size for transmission and energy consumption.

  8. Ground-Based Surveillance and Tracking System (GSTS)

    Science.gov (United States)

    1987-08-01

    reported availabilty of relatively high- paying jobs. The consequences of increased migration could be significant. No significant impacts at U.S. Army...Air Force Base are contributing to overdrawing the aquifers, and at current usage rates the aquifers could be depleted (44). The "Draft Environmental

  9. Retrodirective tracking of a moving target using phase conjugate light generated in a Fabry-Pérot Nd:YAG laser

    Science.gov (United States)

    Kawakami, K.; Komurasaki, K.; Okamura, H.

    2017-03-01

    This report describes the retrodirective tracking of a target moving at a constant speed using a Fabry-Pérot laser resonator-type self-starting phase conjugator. Three-dimensional pointing ability was confirmed with this system: the generated phase conjugate light can focus at a target position. To track the moving targets, target-reflected light is Doppler-shifted, which causes wash-out of the gain grating. To address this problem, numerical analysis and experiments showed that shortening the pulse width is an efficient means of eliminating the gain grating wash-out effect. For the measured target speeds of 0-80 mm/s, the phase conjugate light output is unaffected when the pulse width of 18 ns was used, in contrast to the case of 400 μs pulse width, where the phase conjugate light output rapidly decreased as the target speed approached 10 mm/s. Numerical simulation revealed that phase conjugate light can even be generated for fast-moving targets such as space debris in low-earth-orbit with pulses of several tens of picoseconds. Unlike conventional mechanical gimbal steering methods, this system is applicable for wireless energy transfer to rapidly moving objects.

  10. Vision-Based Leader Vehicle Trajectory Tracking for Multiple Agricultural Vehicles.

    Science.gov (United States)

    Zhang, Linhuan; Ahamed, Tofael; Zhang, Yan; Gao, Pengbo; Takigawa, Tomohiro

    2016-04-22

    The aim of this study was to design a navigation system composed of a human-controlled leader vehicle and a follower vehicle. The follower vehicle automatically tracks the leader vehicle. With such a system, a human driver can control two vehicles efficiently in agricultural operations. The tracking system was developed for the leader and the follower vehicle, and control of the follower was performed using a camera vision system. A stable and accurate monocular vision-based sensing system was designed, consisting of a camera and rectangular markers. Noise in the data acquisition was reduced by using the least-squares method. A feedback control algorithm was used to allow the follower vehicle to track the trajectory of the leader vehicle. A proportional-integral-derivative (PID) controller was introduced to maintain the required distance between the leader and the follower vehicle. Field experiments were conducted to evaluate the sensing and tracking performances of the leader-follower system while the leader vehicle was driven at an average speed of 0.3 m/s. In the case of linear trajectory tracking, the RMS errors were 6.5 cm, 8.9 cm and 16.4 cm for straight, turning and zigzag paths, respectively. Again, for parallel trajectory tracking, the root mean square (RMS) errors were found to be 7.1 cm, 14.6 cm and 14.0 cm for straight, turning and zigzag paths, respectively. The navigation performances indicated that the autonomous follower vehicle was able to follow the leader vehicle, and the tracking accuracy was found to be satisfactory. Therefore, the developed leader-follower system can be implemented for the harvesting of grains, using a combine as the leader and an unloader as the autonomous follower vehicle.

  11. Time-driven Activity-based Cost of Fast-Track Total Hip and Knee Arthroplasty.

    Science.gov (United States)

    Andreasen, Signe E; Holm, Henriette B; Jørgensen, Mira; Gromov, Kirill; Kjærsgaard-Andersen, Per; Husted, Henrik

    2017-06-01

    Fast-track total hip and knee arthroplasty (THA and TKA) has been shown to reduce the perioperative convalescence resulting in less postoperative morbidity, earlier fulfillment of functional milestones, and shorter hospital stay. As organizational optimization is also part of the fast-track methodology, the result could be a more cost-effective pathway altogether. As THA and TKA are potentially costly procedures and the numbers are increasing in an economical limited environment, the aim of this study is to present baseline detailed economical calculations of fast-track THA and TKA and compare this between 2 departments with different logistical set-ups. Prospective data collection was analyzed using the time-driven activity-based costing method (TDABC) on time consumed by different staff members involved in patient treatment in the perioperative period of fast-track THA and TKA in 2 Danish orthopedic departments with standardized fast-track settings, but different logistical set-ups. Length of stay was median 2 days in both departments. TDABC revealed minor differences in the perioperative settings between departments, but the total cost excluding the prosthesis was similar at USD 2511 and USD 2551, respectively. Fast-track THA and TKA results in similar cost despite differences in the organizational set-up. Compared to cost associated with longer more conventional published pathways, fast-track is cheaper, which on top of the favorable published clinical outcome adds to cost efficiency and the potential for economic savings. Detailed baseline TDABC calculations are provided for comparison and further optimization of cost-benefit effectiveness. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Cherenkov light-based beam profiling for ultrarelativistic electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Adli, E., E-mail: Erik.Adli@fys.uio.no [Department of Physics, University of Oslo, N-0316 Oslo (Norway); SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Gessner, S.J.; Corde, S.; Hogan, M.J. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Bjerke, H.H. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2015-05-21

    We describe a beam profile monitor design based on Cherenkov light emitted from a charged particle beam in an air gap. The main components of the profile monitor are silicon wafers used to reflect Cherenkov light onto a camera lens system. The design allows for measuring large beam sizes, with large photon yield per beam charge and excellent signal linearity with beam charge. The profile monitor signal is independent of the particle energy for ultrarelativistic particles. Different design and parameter considerations are discussed. A Cherenkov light-based profile monitor has been installed at the FACET User Facility at SLAC. We report on the measured performance of this profile monitor.

  13. Appearance-Based Multimodal Human Tracking and Identification for Healthcare in the Digital Home

    Directory of Open Access Journals (Sweden)

    Mau-Tsuen Yang

    2014-08-01

    Full Text Available There is an urgent need for intelligent home surveillance systems to provide home security, monitor health conditions, and detect emergencies of family members. One of the fundamental problems to realize the power of these intelligent services is how to detect, track, and identify people at home. Compared to RFID tags that need to be worn all the time, vision-based sensors provide a natural and nonintrusive solution. Observing that body appearance and body build, as well as face, provide valuable cues for human identification, we model and record multi-view faces, full-body colors and shapes of family members in an appearance database by using two Kinects located at a home’s entrance. Then the Kinects and another set of color cameras installed in other parts of the house are used to detect, track, and identify people by matching the captured color images with the registered templates in the appearance database. People are detected and tracked by multisensor fusion (Kinects and color cameras using a Kalman filter that can handle duplicate or partial measurements. People are identified by multimodal fusion (face, body appearance, and silhouette using a track-based majority voting. Moreover, the appearance-based human detection, tracking, and identification modules can cooperate seamlessly and benefit from each other. Experimental results show the effectiveness of the human tracking across multiple sensors and human identification considering the information of multi-view faces, full-body clothes, and silhouettes. The proposed home surveillance system can be applied to domestic applications in digital home security and intelligent healthcare.

  14. Monocular Vision-Based Robot Localization and Target Tracking

    Directory of Open Access Journals (Sweden)

    Bing-Fei Wu

    2011-01-01

    Full Text Available This paper presents a vision-based technology for localizing targets in 3D environment. It is achieved by the combination of different types of sensors including optical wheel encoders, an electrical compass, and visual observations with a single camera. Based on the robot motion model and image sequences, extended Kalman filter is applied to estimate target locations and the robot pose simultaneously. The proposed localization system is applicable in practice because it is not necessary to have the initializing setting regarding starting the system from artificial landmarks of known size. The technique is especially suitable for navigation and target tracing for an indoor robot and has a high potential extension to surveillance and monitoring for Unmanned Aerial Vehicles with aerial odometry sensors. The experimental results present “cm” level accuracy of the localization of the targets in indoor environment under a high-speed robot movement.

  15. Kalman Filter Based Tracking in an Video Surveillance System

    OpenAIRE

    SULIMAN, C.; CRUCERU, C.; Moldoveanu, F.

    2010-01-01

    In this paper we have developed a Matlab/Simulink based model for monitoring a contact in a video surveillance sequence. For the segmentation process and corect identification of a contact in a surveillance video, we have used the Horn-Schunk optical flow algorithm. The position and the behavior of the correctly detected contact were monitored with the help of the traditional Kalman filter. After that we have compared the results obtained from the optical flow method with the ones obtaine...

  16. 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/or cylin...

  17. Multiple Maneuvering Target Tracking by Improved Particle Filter Based on Multiscan JPDA

    Directory of Open Access Journals (Sweden)

    Jing Liu

    2012-01-01

    Full Text Available The multiple maneuvering target tracking algorithm based on a particle filter is addressed. The equivalent-noise approach is adopted, which uses a simple dynamic model consisting of target state and equivalent noise which accounts for the combined effects of the process noise and maneuvers. The equivalent-noise approach converts the problem of maneuvering target tracking to that of state estimation in the presence of nonstationary process noise with unknown statistics. A novel method for identifying the nonstationary process noise is proposed in the particle filter framework. Furthermore, a particle filter based multiscan Joint Probability Data Association (JPDA filter is proposed to deal with the data association problem in a multiple maneuvering target tracking. In the proposed multiscan JPDA algorithm, the distributions of interest are the marginal filtering distributions for each of the targets, and these distributions are approximated with particles. The multiscan JPDA algorithm examines the joint association events in a multiscan sliding window and calculates the marginal posterior probability based on the multiscan joint association events. The proposed algorithm is illustrated via an example involving the tracking of two highly maneuvering, at times closely spaced and crossed, targets, based on resolved measurements.

  18. Mobile Augmented Reality Support for Architects based on feature Tracking Techniques

    DEFF Research Database (Denmark)

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

    2004-01-01

    This paper presents a mobile Augmented Reality (AR) system called the SitePack supporting architects in visualizing 3D models in real-time on site. We describe how vision based feature tracking techniques can help architects making decisions on site concerning visual impact assessment. The AR...

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

    Science.gov (United States)

    Gu, Guoying; Zhu, Limin

    2010-08-01

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

  20. Mobile Augmented Reality Support for Architects based on feature Tracking Techniques

    DEFF Research Database (Denmark)

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

    2004-01-01

    This paper presents a mobile Augmented Reality (AR) system called the SitePack supporting architects in visualizing 3D models in real-time on site. We describe how vision based feature tracking techniques can help architects making decisions on site concerning visual impact assessment. The AR...

  1. Tracking control and synchronization of chaotic systems based upon sampled-data feedback

    Institute of Scientific and Technical Information of China (English)

    陈士华; 刘杰; 谢进; 陆君安

    2002-01-01

    A novel tracking control and synchronization method is proposed based upon sampled-data feedback. This methodcan make a chaotic system approach any desired smooth orbit and synchronize the driving system and the responsesystem, both in the same structure and in diverse structures. Finally, a numerical simulation with a Lorenz system isprovided for the purpose of illustration and verification.

  2. Towards a Classification of Translation Styles based on Eye-tracking and Keylogging Data

    DEFF Research Database (Denmark)

    Dragsted, Barbara; Carl, Michael

    2013-01-01

    This article seeks to formulate translator profiles based on process data from keylogging and eye-tracking, while at the same time identifying features which are shared by all translators in a sample consisting of both students and professionals. Data have been collected from 12 professional...

  3. BACKGROUND RECONSTRUCTION AND OBJECT EXTRACTION BASED ON COLOR AND OBJECT TRACKING

    Institute of Scientific and Technical Information of China (English)

    XIANG Guishan; WANG Xuanyin; LIANG Dongtai

    2006-01-01

    In YCbCr colorspace, a method is proposed to reconstruct the background and extract moving objects based on the Gaussian model of chroma components. Background model is updated according to changes of chroma components. In order to eliminate the disturbance of shadow, a shadow detecting principle is proposed in YCbCr colorspace. A Kalman filter is introduced to estimate objects' positions in the image and then the pedestrian is tracked according to its information of shape. Experiments show that the background reconstruction and updating are successful, object extraction and shadow suppression are satisfactory, and real-time and reliable tracking is realized.

  4. Islanding Detection for Microgrid Based on Frequency Tracking Using Extended Kalman Filter Algorithm

    Directory of Open Access Journals (Sweden)

    Bin Li

    2014-01-01

    Full Text Available Islanding detection is essential for secure and reliable operation of microgrids. Considering the relationship between the power generation and the load in microgrids, frequency may vary with time when islanding occurs. As a common approach, frequency measurement is widely used to detect islanding condition. In this paper, a novel frequency calculation algorithm based on extended Kalman filter was proposed to track dynamic frequency of the microgrid. Taylor series expansion was introduced to solve nonlinear state equations. In addition, a typical microgrid model was built using MATLAB/SIMULINK. Simulation results demonstrated that the proposed algorithm achieved great stability and strong robustness in of tracking dynamic frequency.

  5. Video-Based Eye Tracking in Sex Research: A Systematic Literature Review.

    Science.gov (United States)

    Wenzlaff, Frederike; Briken, Peer; Dekker, Arne

    2015-12-21

    Although eye tracking has been used for decades, it has gained popularity in the area of sex research only recently. The aim of this article is to examine the potential merits of eye tracking for this field. We present a systematic review of the current use of video-based eye-tracking technology in this area, evaluate the findings, and identify future research opportunities. A total of 34 relevant studies published between 2006 and 2014 were identified for inclusion by means of online databases and other methods. We grouped them into three main areas of research: body perception and attractiveness, forensic research, and sexual orientation. Despite the methodological and theoretical differences across the studies, eye tracking has been shown to be a promising tool for sex research. The article suggests there is much potential for further studies to employ this technique because it is noninvasive and yet still allows for the assessment of both conscious and unconscious perceptional processes. Furthermore, eye tracking can be implemented in investigations of various theoretical backgrounds, ranging from biology to the social sciences.

  6. Vision-Based Long-Range 3D Tracking, applied to Underground Surveying Tasks

    Science.gov (United States)

    Mossel, Annette; Gerstweiler, Georg; Vonach, Emanuel; Kaufmann, Hannes; Chmelina, Klaus

    2014-04-01

    To address the need of highly automated positioning systems in underground construction, we present a long-range 3D tracking system based on infrared optical markers. It provides continuous 3D position estimation of static or kinematic targets with low latency over a tracking volume of 12 m x 8 m x 70 m (width x height x depth). Over the entire volume, relative 3D point accuracy with a maximal deviation ≤ 22 mm is ensured with possible target rotations of yaw, pitch = 0 - 45° and roll = 0 - 360°. No preliminary sighting of target(s) is necessary since the system automatically locks onto a target without user intervention and autonomously starts tracking as soon as a target is within the view of the system. The proposed system needs a minimal hardware setup, consisting of two machine vision cameras and a standard workstation for data processing. This allows for quick installation with minimal disturbance of construction work. The data processing pipeline ensures camera calibration and tracking during on-going underground activities. Tests in real underground scenarios prove the system's capabilities to act as 3D position measurement platform for multiple underground tasks that require long range, low latency and high accuracy. Those tasks include simultaneously tracking of personnel, machines or robots.

  7. RFID Based e-quality tracking in service-oriented manufacturing execution system

    Science.gov (United States)

    Fu, Yingbin; Jiang, Pingyu

    2012-09-01

    The method of acquiring the real-time data has influenced the implementation of the manufacturing execution system (MES). Accompanied with turning the MES into service-oriented manufacturing execution system (so-MES), real-time e-quality tracking (e-QT), in which real-time data are computed, has played more and more important roles in manufacturing. This paper presents an e-QT model through the study of real-time status data tracking and quality data collecting. An implementing architecture of the e-QT model is constructed on the basis of radio frequency identification devices (RFID) data-tracking network. In order to develop the e-QT system, some key enabling technologies, such as configuration, data collection, and data processing, etc, are studied. The relation schema between hardware is built for the RFID data-tracking network based on the configuration technique. Real-time data are sampled by using data collecting technique. Furthermore, real-time status and quality data in a shop-floor can be acquired in terms of using the real-time data computing method. Finally, a prototype system is developed and a running example is given so as to verify the feasibility of methods proposed in this paper. The proposed research provides effective e-quality tracking theoretical foundation through the use of RFID technology for the discrete manufacturing.

  8. Pulse width modulation-based temperature tracking for feedback control of a shape memory alloy actuator.

    Science.gov (United States)

    Ayvali, Elif; Desai, Jaydev P

    2014-04-01

    This work presents a temperature-feedback approach to control the radius of curvature of an arc-shaped shape memory alloy (SMA) wire. The nonlinear properties of the SMA such as phase transformation and its dependence on temperature and stress make SMA actuators difficult to control. Tracking a desired trajectory is more challenging than controlling just the position of the SMA actuator since the desired path is continuously changing. Consequently, tracking the desired strain directly or tracking the parameters such as temperature and electrical resistance that are related to strain with a model is a challenging task. Temperature-feedback is an attractive approach when direct measurement of strain is not practical. Pulse width modulation (PWM) is an effective method for SMA actuation and it can be used along with a compensator to control the temperature of the SMA. Using the constitutive model of the SMA, the desired temperature profile can be obtained for a given strain trajectory. A PWM-based nonlinear PID controller with a feed-forward heat transfer model is proposed to use temperature-feedback for tracking a desired temperature trajectory. The proposed controller is used during the heating phase of the SMA actuator. The controller proves to be effective in tracking step-wise and continuous trajectories.

  9. Node Topology Effect on Target Tracking Based on UWSNs Using Quantized Measurements.

    Science.gov (United States)

    Zhang, Qiang; Liu, Meiqin; Zhang, Senlin

    2015-10-01

    On one hand, due to the energy and bandwidth constraint of underwater wireless sensor networks (UWSNs), local data quantization/compression is not only a necessity, but also an integral part of the design of UWSNs; on the other hand, since underwater nodes provide measurements for target tracking based on UWSNs, node topology, which is made up of the underwater nodes, may affect the performance of target tracking. This paper studies the effect of node topology on the target tracking in UWSNs using quantized measurements. Firstly, by using the knowledge of geometry, the effects of four typical topologies on target tracking using quantized measurements are analyzed qualitatively. The four typical topologies include two nodes are close to each other, three nodes are close to each other, three nodes are co-linear, and three nodes form a regular triangle. Secondly, under the condition of quantized measurements, the relationship between the posterior Cramer-Rao lower bound (PCRLB) and node's position is derived to evaluate the arbitrary topology. Thirdly, our target tracking scheme consisting of the optimal topology selection scheme by minimizing PCRLB, the optimal fusion center selection scheme by minimizing energy consumption, and the multisensor particle filter with quantized measurements is designed. Last, simulation results show the effectiveness of the proposed scheme.

  10. Real-Time Occlusion Handling in Augmented Reality Based on an Object Tracking Approach

    Science.gov (United States)

    Tian, Yuan; Guan, Tao; Wang, Cheng

    2010-01-01

    To produce a realistic augmentation in Augmented Reality, the correct relative positions of real objects and virtual objects are very important. In this paper, we propose a novel real-time occlusion handling method based on an object tracking approach. Our method is divided into three steps: selection of the occluding object, object tracking and occlusion handling. The user selects the occluding object using an interactive segmentation method. The contour of the selected object is then tracked in the subsequent frames in real-time. In the occlusion handling step, all the pixels on the tracked object are redrawn on the unprocessed augmented image to produce a new synthesized image in which the relative position between the real and virtual object is correct. The proposed method has several advantages. First, it is robust and stable, since it remains effective when the camera is moved through large changes of viewing angles and volumes or when the object and the background have similar colors. Second, it is fast, since the real object can be tracked in real-time. Last, a smoothing technique provides seamless merging between the augmented and virtual object. Several experiments are provided to validate the performance of the proposed method. PMID:22319278

  11. Optimized swimmer tracking system based on a novel multi-related-targets approach

    Science.gov (United States)

    Benarab, D.; Napoléon, T.; Alfalou, A.; Verney, A.; Hellard, P.

    2017-02-01

    Robust tracking is a crucial step in automatic swimmer evaluation from video sequences. We designed a robust swimmer tracking system using a new multi-related-targets approach. The main idea is to consider the swimmer as a bloc of connected subtargets that advance at the same speed. If one of the subtargets is partially or totally occluded, it can be localized by knowing the position of the others. In this paper, we first introduce the two-dimensional direct linear transformation technique that we used to calibrate the videos. Then, we present the classical tracking approach based on dynamic fusion. Next, we highlight the main contribution of our work, which is the multi-related-targets tracking approach. This approach, the classical head-only approach and the ground truth are then compared, through testing on a database of high-level swimmers in training, national and international competitions (French National Championships, Limoges 2015, and World Championships, Kazan 2015). Tracking percentage and the accuracy of the instantaneous speed are evaluated and the findings show that our new appraoach is significantly more accurate than the classical approach.

  12. Semantic Contours in Tracks Based on Emotional Tags

    DEFF Research Database (Denmark)

    Petersen, Michael Kai; Hansen, Lars Kai; Butkus, Andrius

    2009-01-01

    Outlining a high level cognitive approach to how we select media based on affective user preferences, we model the latent semantics of lyrics as patterns of emotional components. Using a selection of affective last.fm tags as top-down emotional buoys, we apply LSA latent semantic analysis to bottom......-up represent the correlation of terms and song lyrics in a vector space that reflects the emotional context. Analyzing the resulting patterns of affective components, by comparing them against last.fm tag clouds describing the corresponding songs, we propose that it might be feasible to automatically generate...

  13. Robust object tracking based on structural local sparsity via a global L2 norm constraint

    Science.gov (United States)

    Li, Meihui; Peng, Zhenming; Zhang, Ping

    2016-10-01

    In the structural local sparse model, every candidate derived from the particle filter framework is divided into several overlapping image patches. However, in the tracking process, the structural characteristics of the target may change due to alterations in appearance, resulting in unstable pooled features and therefore drifting and false tracking. We propose a method to correct the changed part of the target using atoms in the patched dictionary by adding a global constraint. If the target is corrupted, this constraint term will weaken the influence of variation and strengthen the stability of the pooled features. Otherwise, the method is based on the whole target and will protect its spatial continuity. Both qualitative and quantitative evaluations on challenging benchmark image sequences demonstrate that the proposed algorithm has excellent tracking behavior, displaying robustness and stability with little drifting on a target with altering appearance and partial occlusion.

  14. Particle filter based visual tracking with multi-cue adaptive fusion

    Institute of Scientific and Technical Information of China (English)

    Anping Li; Zhongliang Jing; Shiqiang Hu

    2005-01-01

    @@ To improve the robustness of visual tracking in complex environments such as: cluttered backgrounds, partial occlusions, similar distraction and pose variations, a novel tracking method based on adaptive fusion and particle filter is proposed in this paper. In this method, the image color and shape cues are adaptively fused to represent the target observation; fuzzy logic is applied to dynamically adjust each cue weight according to its associated reliability in the past frame; particle filter is adopted to deal with non-linear and non-Gaussian problems in visual tracking. The method is demonstrated to be robust to illumination changes, pose variations, partial occlusions, cluttered backgrounds and camera motion for a test image sequence.

  15. Infrared dim target tracking based on guide filter and Bayes classification

    Science.gov (United States)

    Qian, Kun; Zhou, Hui-xin; Qin, Han-lin; Song, Shang-zhen; Zhao, Dong; Wang, Bing-jian

    2016-10-01

    An infrared dim and small tracking is proposed based on an explicit image filter - guided filter. The guided filter utilizes the structure in the guidance image and performs as an edge-preserving smoothing operator. The superior performance depending on the guidance image is critical advantage for target tracking. First, the guided filter can help to preserve the detail of the valuable templates and make the inaccurate ones blurry so that the tracker can distinguish the target from numerous bad templates easily. Besides, the filter can recover the content of the small target being influenced according to the guidance image, helping to alleviate the drifting problem effectively. Finally, the candidate samples are utilized to train an effective Bayes classifier to generate a robust tracker, which is easy to be implemented. Experimental results demonstrate that the presented method can track the target effectively, compared with several classical methods. Experimental results show that the proposed algorithm outperforms relative trackers in the accuracy and the robustness.

  16. Steering Dynamic Performance of an Electric Transmission Tracked Vehicle Based on Rotating Speed Control

    Institute of Scientific and Technical Information of China (English)

    SUN Feng-chun; CHEN Shu-yong; ZHANG Cheng-ning

    2006-01-01

    In order to analyze steering dynamic performance of an electric transmission tracked vehicle exactly, modern design theory and methodology-collaborative simulation and virtual prototype are applied. The 3-D multi-body dynamic model of full vehicle running gears and control system model are built based on the simulation platform on dynamic analysis software known as RecurDyn/Track-HM and control system analysis software known as Matlab/Simulink. Theory analysis and collaborative simulation of turning kinematic/dynamic performance in different velocity and turning radius are made. Comparing the test result with theory computation validates the correctness of the model. The method has instructional significance of solving the existent modeling problem, comprehension of turning performance and test debugging strategy,and also forms a new idea of research on dynamic characteristics for the electric transmission tracked vehicle's electric propulsion system.

  17. Performance-Based Adaptive Fuzzy Tracking Control for Networked Industrial Processes.

    Science.gov (United States)

    Wang, Tong; Qiu, Jianbin; Yin, Shen; Gao, Huijun; Fan, Jialu; Chai, Tianyou

    2016-08-01

    In this paper, the performance-based control design problem for double-layer networked industrial processes is investigated. At the device layer, the prescribed performance functions are first given to describe the output tracking performance, and then by using backstepping technique, new adaptive fuzzy controllers are designed to guarantee the tracking performance under the effects of input dead-zone and the constraint of prescribed tracking performance functions. At operation layer, by considering the stochastic disturbance, actual index value, target index value, and index prediction simultaneously, an adaptive inverse optimal controller in discrete-time form is designed to optimize the overall performance and stabilize the overall nonlinear system. Finally, a simulation example of continuous stirred tank reactor system is presented to show the effectiveness of the proposed control method.

  18. Target acquisition and tracking based on a priori knowledge and an image sensor

    Science.gov (United States)

    Fang, Zhonghua; Chen, Tao

    2002-07-01

    When intercepting and tracking low-observable point-source or highly maneuvering big targets, the electro-optical (E-O) system will meet a fatal problem that the target lost easily. No effective method intercepts it again according to the dispersed azimuth and elevation tracking data. First, the paper gives an intelligent ATP control system architecture based on the data mart. Then an automatic real-time control algorithm is proposed, which is found on linguistic cloud model and fuzzy logic techniques. The linguistic cloud model is used to translate a linguistic term of qualitative concept into its numerical representation, such that the ATP control system can take full advantage of a priori knowledge which is always presented in natural language to refine the results of sequence images processing. The fuzzy logic technique is adopted to associate these results to target's trajectories. The paper offers an automatic reacquisition and tracking method to solve the targets lost problem.

  19. Active disturbance rejection control based human gait tracking for lower extremity rehabilitation exoskeleton.

    Science.gov (United States)

    Long, Yi; Du, Zhijiang; Cong, Lin; Wang, Weidong; Zhang, Zhiming; Dong, Wei

    2017-03-01

    This paper presents an active disturbance rejection control (ADRC) based strategy, which is applied to track the human gait trajectory for a lower limb rehabilitation exoskeleton. The desired human gait trajectory is derived from the Clinical Gait Analysis (CGA). In ADRC, the total external disturbance can be estimated by the extended state observer (ESO) and canceled by the designed control law. The observer bandwidth and the controller bandwidth are determined by the practical principles. We simulated the proposed methodology in MATLAB. The numerical simulation shows the tracking error comparison and the estimated errors of the extended state observer. Two experimental tests were carried out to prove the performance of the algorithm presented in this paper. The experiment results show that the proposed ADRC behaves a better performance than the regular proportional integral derivative (PID) controller. With the proposed ADRC, the rehabilitation system is capable of tracking the target gait more accurately.

  20. A novel active disturbance rejection based tracking design for laser system with quadrant photodetector

    Science.gov (United States)

    Manojlović, Stojadin M.; Barbarić, Žarko P.; Mitrović, Srđan T.

    2015-06-01

    A new tracking design for laser systems with different arrangements of a quadrant photodetector, based on the principle of active disturbance rejection control is suggested. The detailed models of quadrant photodetector with standard add-subtract, difference-over-sum and diagonal-difference-over-sum algorithms for displacement signals are included in the control loop. Target moving, non-linearity of a photodetector, parameter perturbations and exterior disturbances are treated as a total disturbance. Active disturbance rejection controllers with linear extended state observers for total disturbance estimation and rejection are designed. Proposed methods are analysed in frequency domain to quantify their stability characteristics and disturbance rejection performances. It is shown through simulations, that tracking errors are effectively compensated, providing the laser spot positioning in the area near the centre of quadrant photodetector where the mentioned algorithms have the highest sensitivity, which provides tracking of the manoeuvring targets with high accuracy.

  1. Observer-based approximate optimal tracking control for time-delay systems with external disturbances

    Science.gov (United States)

    Su, Hao; Tang, Gong-You

    2016-09-01

    This paper proposes a successive approximation design approach of observer-based optimal tracking controllers for time-delay systems with external disturbances. To solve a two-point boundary value problem with time-delay and time-advance terms and obtain the optimal tracking control law, two sequences of vector differential equations are constructed first. Second, the convergence of the sequences of the vector differential equations is proved to guarantee the existence and uniqueness of the control law. Third, a design algorithm of the optimal tracking control law is presented and the physically realisable problem is addressed by designing a disturbance state observer and a reference input state observer. An example of an industrial electric heater is given to demonstrate the efficiency of the proposed approach.

  2. Design and Manufacturing of a High-Precision Sun Tracking System Based on Image Processing

    Directory of Open Access Journals (Sweden)

    Kianoosh Azizi

    2013-01-01

    Full Text Available Concentration solar arrays require greater solar tracking precision than conventional photovoltaic arrays. This paper presents a high precision low cost dual axis sun tracking system based on image processing for concentration photovoltaic applications. An imaging device is designed according to the principle of pinhole imaging, making sun rays to be received on a screen through pinhole and to be a sun spot. The location of the spot is used to adjust the orientation of the solar panel. A fuzzy logic controller is developed to achieve this goal. A prototype was built, and experimental results have proven the good performance of the proposed system and low error of tracking. The operation of this system is independent of geographical location, initial calibration, and periodical regulations.

  3. UKF-based multi-sensor passive tracking with active assistance

    Institute of Scientific and Technical Information of China (English)

    Li Anping; Jing Zhongliang; Hu Shiqiang

    2006-01-01

    A new synergy tracking method of infrared and radar is presented. To improve tracking accuracy, the unscented Kalman filter (UKF), which has better nonlinear approximation ability, is adopted. In addition, to reduce the possibility of radar being locked-on by adverse electronic support measure (ESM), radar is under the intermittent-working state. After radar is turned off, the possible target position is estimated by a set of time polynomials,which is constructed based on the sufficient observations done before radar is turned off, the estimated values from time polynomials are compared with the current observation values from infrared to determine the time when radar is turned on. Simulation results show the method has a good tracking accuracy and effectively reduces the possibility of radar being locked-on by adverse ESM.

  4. Long-Short Market Neutral and Index Tracking Strategies Based on Cointegrated Portfolios

    Directory of Open Access Journals (Sweden)

    João Frois Caldeira

    2010-12-01

    Full Text Available The traditional models to optimize portfolios based on mean-variance analysis aim to determine the portfolio weights that minimize the variance for a certain return level. The covariance matrices used to optimize are difficult to estimate and ad hoc methods often need to be applied to limit or smooth the mean-variance efficient allocations recommended by the model. Although the method is efficient, the tracking error isn’t certainly stationary, so the portfolio can get distant from the benchmark, requiring frequent re-balancements. This work uses cointegration methodology to devise two quantitative strategies: index tracking and long-short market neutral. We aim to design optimal portfolios acquiring the asset prices’ co-movements. The results show that the devise of index tracking portfolios using cointegration generates goods results, replicating the benchmark’s return and volatility. The long-short strategy generated stable returns under several market circumstances, presenting low volatility.

  5. Evidence-based surgical care and the evolution of fast-track surgery

    DEFF Research Database (Denmark)

    Kehlet, H.; Wilmore, D.W.

    2008-01-01

    , randomized studies, and meta-analyses, the concept of the "fast-track methodology" has uniformly provided a major enhancement in recovery leading to decreased hospital stay and with an apparent reduction in medical morbidity but unaltered "surgery-specific" morbidity in a variety of procedures. However......BACKGROUND: Optimization of postoperative outcome requires the application of evidence-based principles of care carefully integrated into a multimodal rehabilitation program. OBJECTIVE: To assess, synthesize, and discuss implementation of "fast-track" recovery programs. DATA SOURCES: Medline MBASE...... (January 1966-May 2007) and the Cochrane library (January 1966-May 2007) were searched using the following keywords: fast-track, enhanced recovery, accelerated rehabilitation, and multimodal and perioperative care. In addition, the synthesis on the many specific interventions and organizational...

  6. River Flow Lane Detection and Kalman Filtering-Based B-Spline Lane Tracking

    Directory of Open Access Journals (Sweden)

    King Hann Lim

    2012-01-01

    Full Text Available A novel lane detection technique using adaptive line segment and river flow method is proposed in this paper to estimate driving lane edges. A Kalman filtering-based B-spline tracking model is also presented to quickly predict lane boundaries in consecutive frames. Firstly, sky region and road shadows are removed by applying a regional dividing method and road region analysis, respectively. Next, the change of lane orientation is monitored in order to define an adaptive line segment separating the region into near and far fields. In the near field, a 1D Hough transform is used to approximate a pair of lane boundaries. Subsequently, river flow method is applied to obtain lane curvature in the far field. Once the lane boundaries are detected, a B-spline mathematical model is updated using a Kalman filter to continuously track the road edges. Simulation results show that the proposed lane detection and tracking method has good performance with low complexity.

  7. Smoother and Bayesian filter based semi-codeless tracking of dual-frequency GPS signals

    Institute of Scientific and Technical Information of China (English)

    LIAO Bingyu; YUAN Hong; LIN Baojun

    2006-01-01

    To precisely determine the integrated orbit of the Chinese manned spacecraft mission,a smoother and Bayesian filter based technique for optimum semi-codeless tracking of the P(Y) code on dual-frequency GPS signals has been advanced. This signal processing technique has been proven effective and robust for affording access to dual-frequency GPS signals. This paper introduces the signal dynamics and measurement models, describes the W·D bit estimation method, and corrects the mistakes of direct estimation of W bit in current semi-codeless tracking. Median filter is chosen as a smoother to find the best measurements at the current time among the history and current information. The Bayesian filter is used to track the L2 P(Y) code phase and L2 carrier phase recursively.

  8. In the twinkling of an eye: synchronization of EEG and eye tracking based on blink signatures

    DEFF Research Database (Denmark)

    Bækgaard, Per; Petersen, Michael Kai; Larsen, Jakob Eg

    2014-01-01

    be integrated into next generation user interfaces. In experimental lab settings EEG neuroimaging and eye tracking data are traditionally combined using external triggers to synchronize the signals. However, with biometric sensors increasingly being applied in everyday usage scenarios, there will be a need...... for solutions providing a continuous alignment of signals. In the present paper we propose using spontaneous eye blinks, as a means to achieve near real-time synchronization of EEG and eye tracking. Analyzing key parameters that define eye blink signatures across the two domains, we outline a probability...... function based algorithm to correlate the signals. Comparing the accuracy of the method against a state of the art EYE-EEG plug-in for offline analysis of EEG and eye tracking data, we propose our approach could be applied for robust synchronization of biometric sensor data collected in a mobile context....

  9. A Back-stepping Based Trajectory Tracking Controller for a Non-chained Nonholonomic Spherical Robot

    Institute of Scientific and Technical Information of China (English)

    Zhan Qiang; Liu Zengbo; Cai Yao

    2008-01-01

    Spherical robot has good static and dynamic stability, which provides it with strong viability in hostile environment, but the lack of effective control methods has hindered its application and development. This article deals with the dynamic trajectory tracking problem of the spherical robot BHQ-2 designed for unmanned environment exploration. The dynamic model of the spherical robot is established with a simplified Boltzmann-Hamel equation, based on which a trajectory tracking controller is designed by using the back-stepping method. The convergence of the controller is proved with the Lyapunov stability theory. Numerical simulations show that with the controller the robot can globally and asymptotically track desired trajectories, both linear and circular.

  10. Pricise Target Geolocation and Tracking Based on Uav Video Imagery

    Science.gov (United States)

    Hosseinpoor, H. R.; Samadzadegan, F.; Dadrasjavan, F.

    2016-06-01

    There is an increasingly large number of applications for Unmanned Aerial Vehicles (UAVs) from monitoring, mapping and target geolocation. However, most of commercial UAVs are equipped with low-cost navigation sensors such as C/A code GPS and a low-cost IMU on board, allowing a positioning accuracy of 5 to 10 meters. This low accuracy cannot be used in applications that require high precision data on cm-level. This paper presents a precise process for geolocation of ground targets based on thermal video imagery acquired by small UAV equipped with RTK GPS. The geolocation data is filtered using an extended Kalman filter, which provides a smoothed estimate of target location and target velocity. The accurate geo-locating of targets during image acquisition is conducted via traditional photogrammetric bundle adjustment equations using accurate exterior parameters achieved by on board IMU and RTK GPS sensors, Kalman filtering and interior orientation parameters of thermal camera from pre-flight laboratory calibration process. The results of this study compared with code-based ordinary GPS, indicate that RTK observation with proposed method shows more than 10 times improvement of accuracy in target geolocation.

  11. PRICISE TARGET GEOLOCATION AND TRACKING BASED ON UAV VIDEO IMAGERY

    Directory of Open Access Journals (Sweden)

    H. R. Hosseinpoor

    2016-06-01

    Full Text Available There is an increasingly large number of applications for Unmanned Aerial Vehicles (UAVs from monitoring, mapping and target geolocation. However, most of commercial UAVs are equipped with low-cost navigation sensors such as C/A code GPS and a low-cost IMU on board, allowing a positioning accuracy of 5 to 10 meters. This low accuracy cannot be used in applications that require high precision data on cm-level. This paper presents a precise process for geolocation of ground targets based on thermal video imagery acquired by small UAV equipped with RTK GPS. The geolocation data is filtered using an extended Kalman filter, which provides a smoothed estimate of target location and target velocity. The accurate geo-locating of targets during image acquisition is conducted via traditional photogrammetric bundle adjustment equations using accurate exterior parameters achieved by on board IMU and RTK GPS sensors, Kalman filtering and interior orientation parameters of thermal camera from pre-flight laboratory calibration process. The results of this study compared with code-based ordinary GPS, indicate that RTK observation with proposed method shows more than 10 times improvement of accuracy in target geolocation.

  12. A review on visible light active perovskite-based photocatalysts.

    Science.gov (United States)

    Kanhere, Pushkar; Chen, Zhong

    2014-12-01

    Perovskite-based photocatalysts are of significant interest in the field of photocatalysis. To date, several perovskite material systems have been developed and their applications in visible light photocatalysis studied. This article provides a review of the visible light (λ > 400 nm) active perovskite-based photocatalyst systems. The materials systems are classified by the B site cations and their crystal structure, optical properties, electronic structure, and photocatalytic performance are reviewed in detail. Titanates, tantalates, niobates, vanadates, and ferrites form important photocatalysts which show promise in visible light-driven photoreactions. Along with simple perovskite (ABO3) structures, development of double/complex perovskites that are active under visible light is also reviewed. Various strategies employed for enhancing the photocatalytic performance have been discussed, emphasizing the specific advantages and challenges offered by perovskite-based photocatalysts. This review provides a broad overview of the perovskite photocatalysts, summarizing the current state of the work and offering useful insights for their future development.

  13. ‘PhysTrack’: a Matlab based environment for video tracking of kinematics in the physics laboratory

    Science.gov (United States)

    Umar Hassan, Muhammad; Sabieh Anwar, Muhammad

    2017-07-01

    In the past two decades, several computer software tools have been developed to investigate the motion of moving bodies in physics laboratories. In this article we report a Matlab based video tracking library, PhysTrack, primarily designed to investigate kinematics. We compare PhysTrack with other commonly available video tracking tools and outline its salient features. The general methodology of the whole video tracking process is described with a step by step explanation of several functionalities. Furthermore, results of some real physics experiments are also provided to demonstrate the working of the automated video tracking, data extraction, data analysis and presentation tools that come with this development environment. We believe that PhysTrack will be valuable for the large community of physics teachers and students already employing Matlab.

  14. Improved spring model-based collaborative indoor visible light positioning

    Science.gov (United States)

    Luo, Zhijie; Zhang, WeiNan; Zhou, GuoFu

    2016-06-01

    Gaining accuracy with indoor positioning of individuals is important as many location-based services rely on the user's current position to provide them with useful services. Many researchers have studied indoor positioning techniques based on WiFi and Bluetooth. However, they have disadvantages such as low accuracy or high cost. In this paper, we propose an indoor positioning system in which visible light radiated from light-emitting diodes is used to locate the position of receivers. Compared with existing methods using light-emitting diode light, we present a high-precision and simple implementation collaborative indoor visible light positioning system based on an improved spring model. We first estimate coordinate position information using the visible light positioning system, and then use the spring model to correct positioning errors. The system can be employed easily because it does not require additional sensors and the occlusion problem of visible light would be alleviated. We also describe simulation experiments, which confirm the feasibility of our proposed method.

  15. Online Variational Bayesian Filtering-Based Mobile Target Tracking in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Bingpeng Zhou

    2014-11-01

    Full Text Available The received signal strength (RSS-based online tracking for a mobile node in wireless sensor networks (WSNs is investigated in this paper. Firstly, a multi-layer dynamic Bayesian network (MDBN is introduced to characterize the target mobility with either directional or undirected movement. In particular, it is proposed to employ the Wishart distribution to approximate the time-varying RSS measurement precision’s randomness due to the target movement. It is shown that the proposed MDBN offers a more general analysis model via incorporating the underlying statistical information of both the target movement and observations, which can be utilized to improve the online tracking capability by exploiting the Bayesian statistics. Secondly, based on the MDBN model, a mean-field variational Bayesian filtering (VBF algorithm is developed to realize the online tracking of a mobile target in the presence of nonlinear observations and time-varying RSS precision, wherein the traditional Bayesian filtering scheme cannot be directly employed. Thirdly, a joint optimization between the real-time velocity and its prior expectation is proposed to enable online velocity tracking in the proposed online tacking scheme. Finally, the associated Bayesian Cramer–Rao Lower Bound (BCRLB analysis and numerical simulations are conducted. Our analysis unveils that, by exploiting the potential state information via the general MDBN model, the proposed VBF algorithm provides a promising solution to the online tracking of a mobile node in WSNs. In addition, it is shown that the final tracking accuracy linearly scales with its expectation when the RSS measurement precision is time-varying.

  16. Online variational Bayesian filtering-based mobile target tracking in wireless sensor networks.

    Science.gov (United States)

    Zhou, Bingpeng; Chen, Qingchun; Li, Tiffany Jing; Xiao, Pei

    2014-11-11

    The received signal strength (RSS)-based online tracking for a mobile node in wireless sensor networks (WSNs) is investigated in this paper. Firstly, a multi-layer dynamic Bayesian network (MDBN) is introduced to characterize the target mobility with either directional or undirected movement. In particular, it is proposed to employ the Wishart distribution to approximate the time-varying RSS measurement precision's randomness due to the target movement. It is shown that the proposed MDBN offers a more general analysis model via incorporating the underlying statistical information of both the target movement and observations, which can be utilized to improve the online tracking capability by exploiting the Bayesian statistics. Secondly, based on the MDBN model, a mean-field variational Bayesian filtering (VBF) algorithm is developed to realize the online tracking of a mobile target in the presence of nonlinear observations and time-varying RSS precision, wherein the traditional Bayesian filtering scheme cannot be directly employed. Thirdly, a joint optimization between the real-time velocity and its prior expectation is proposed to enable online velocity tracking in the proposed online tacking scheme. Finally, the associated Bayesian Cramer-Rao Lower Bound (BCRLB) analysis and numerical simulations are conducted. Our analysis unveils that, by exploiting the potential state information via the general MDBN model, the proposed VBF algorithm provides a promising solution to the online tracking of a mobile node in WSNs. In addition, it is shown that the final tracking accuracy linearly scales with its expectation when the RSS measurement precision is time-varying.

  17. Fault Diagnosis for Compensating Capacitors of Jointless Track Circuit Based on Dynamic Time Warping

    Directory of Open Access Journals (Sweden)

    Wei Dong

    2014-01-01

    Full Text Available Aiming at the problem of online fault diagnosis for compensating capacitors of jointless track circuit, a dynamic time warping (DTW based diagnosis method is proposed in this paper. Different from the existing related works, this method only uses the ground indoor monitoring signals of track circuit to locate the faulty compensating capacitor, not depending on the shunt current of inspection train, which is an indispensable condition for existing methods. So, it can be used for online diagnosis of compensating capacitor, which has not yet been realized by existing methods. To overcome the key problem that track circuit cannot obtain the precise position of the train, the DTW method is used for the first time in this situation to recover the function relationship between receiver’s peak voltage and shunt position. The necessity, thinking, and procedure of the method are described in detail. Besides the classical DTW based method, two improved methods for improving classification quality and reducing computation complexity are proposed. Finally, the diagnosis experiments based on the simulation model of track circuit show the effectiveness of the proposed methods.

  18. Ontological Representation of Light Wave Camera Data to Support Vision-Based AmI

    Directory of Open Access Journals (Sweden)

    José Manuel Molina

    2012-09-01

    Full Text Available Recent advances in technologies for capturing video data have opened a vast amount of new application areas in visual sensor networks. Among them, the incorporation of light wave cameras on Ambient Intelligence (AmI environments provides more accurate tracking capabilities for activity recognition. Although the performance of tracking algorithms has quickly improved, symbolic models used to represent the resulting knowledge have not yet been adapted to smart environments. This lack of representation does not allow to take advantage of the semantic quality of the information provided by new sensors. This paper advocates for the introduction of a part-based representational level in cognitive-based systems in order to accurately represent the novel sensors’ knowledge. The paper also reviews the theoretical and practical issues in part-whole relationships proposing a specific taxonomy for computer vision approaches. General part-based patterns for human body and transitive part-based representation and inference are incorporated to an ontology-based previous framework to enhance scene interpretation in the area of video-based AmI. The advantages and new features of the model are demonstrated in a Social Signal Processing (SSP application for the elaboration of live market researches.

  19. Light weight cellular structures based on aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, O. [Indian Inst. of Tech., Kanpur (India); Embury, J.D.; Sinclair, C. [McMaster Univ., Hamilton, ON (Canada); Sang, H. [Queen`s Univ., Kingston, ON (Canada); Silvetti, P. [Cordoba Univ. Nacional (Argentina). Facultad de Ciencias Exactas, Fisicas y Naturales

    1997-02-01

    An interesting form of lightweight material which has emerged in the past 2 decades is metallic foam. This paper deals with the basic concepts of making metallic foams and a detailed study of foams produced from Al-SiC. In addition, some aspects of cellular solids based on honeycomb structures are outlined including the concept of producing both two-phase foams and foams with composite walls.

  20. Lighting

    Data.gov (United States)

    Federal Laboratory Consortium — Lighting Systems Test Facilities aid research that improves the energy efficiency of lighting systems. • Gonio-Photometer: Measures illuminance from each portion of...

  1. PERFORMANCE MEASUREMENTS OF FEATURE TRACKING AND HISTOGRAM BASED TRAFFIC CONGESTION ALGORITHMS

    Directory of Open Access Journals (Sweden)

    Ozgur Altun

    2015-05-01

    Full Text Available In this paper, feature tracking based and histogram based traffic congestion detection systems are developed. Developed all system are designed to run as real time application. In this work, ORB (Oriented FAST and Rotated BRIEF feature extraction method have been used to develop feature tracking based traffic congestion solution. ORB is a rotation invariant, fast and resistant to noise method and contains the power of FAST and BRIEF feature extraction methods. Also, two different approaches, which are standard deviation and weighed average, have been applied to find out the congestion information by using histogram of the image to develop histogram based traffic congestion solution. Both systems have been tested on different weather conditions such as cloudy, sunny and rainy to provide various illumination at both daytime and night. For all developed systems performance results are examined to show the advantages and drawbacks of these systems

  2. Design of a GSM Based Electronic Voting Machine with Voter Tracking

    Directory of Open Access Journals (Sweden)

    Vaibhav Bhatia

    2015-01-01

    Full Text Available This paper presents the design of a GSM based electronic voting machine with voter tracking. The design presented here follows a GSM based approach to send the polling results to a base station via mobile network. Infrared sensors have been used for tracking the information regarding the voters. After the voting process has been over, the results are sent to the base station for various analyses and declaring the verdict. This system is more secured and chances of tampering the results are reduced. The simulation of the system is done on Proteus Professional Software v8.0. The design presented in this paper is more secured and appropriate according to modern day requirements.

  3. A single-electrode based triboelectric nanogenerator as self-powered tracking system.

    Science.gov (United States)

    Yang, Ya; Zhou, Yu Sheng; Zhang, Hulin; Liu, Ying; Lee, Sangmin; Wang, Zhong Lin

    2013-12-03

    A newly designed triboelectric nanogenerator (TENG) is demonstrated based on a contact-separation process between an Al foil and a finite size polyamide (PA) film. The working mechanism is based on charge transfer between the Al foil and ground. A 4×4 matrix of TENG array can be used for tracking motion by recording the output voltages signals in real-time to form a pressure map. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Seam tracking with texture based image processing for laser materials processing

    Science.gov (United States)

    Krämer, S.; Fiedler, W.; Drenker, A.; Abels, P.

    2014-02-01

    This presentation deals with a camera based seam tracking system for laser materials processing. The digital high speed camera records interaction point and illuminated work piece surface. The camera system is coaxially integrated into the laser beam path. The aim is to observe interaction point and joint gap in one image for a closed loop control of the welding process. Especially for the joint gap observation a new image processing method is used. Basic idea is to detect a difference between the textures of the surface of the two work pieces to be welded together instead of looking for a nearly invisible narrow line imaged by the joint gap. The texture based analysis of the work piece surface is more robust and less affected by varying illumination conditions than conventional grey scale image processing. This technique of image processing gives in some cases the opportunity for real zero gap seam tracking. In a condensed view economic benefits are simultaneous laser and seam tracking for self-calibrating laser welding applications without special seam pre preparation for seam tracking.

  5. 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.

  6. Online kernel-based learning for task-space tracking robot control.

    Science.gov (United States)

    Nguyen-Tuong, Duy; Peters, Jan

    2012-09-01

    Task-space control of redundant robot systems based on analytical models is known to be susceptive to modeling errors. Data-driven model learning methods may present an interesting alternative approach. However, learning models for task-space tracking control from sampled data is an ill-posed problem. In particular, the same input data point can yield many different output values, which can form a nonconvex solution space. Because the problem is ill-posed, models cannot be learned from such data using common regression methods. While learning of task-space control mappings is globally ill-posed, it has been shown in recent work that it is locally a well-defined problem. In this paper, we use this insight to formulate a local kernel-based learning approach for online model learning for task-space tracking control. We propose a parametrization for the local model, which makes an application in task-space tracking control of redundant robots possible. The model parametrization further allows us to apply the kernel-trick and, therefore, enables a formulation within the kernel learning framework. In our evaluations, we show the ability of the method for online model learning for task-space tracking control of redundant robots.

  7. Non-cooperative spacecraft pose tracking based on point cloud feature

    Science.gov (United States)

    He, Ying; Liang, Bin; He, Jin; Li, Shunzhi

    2017-10-01

    On-orbit services have been paid more and more attention for its role in spacecraft life-extension, capacity improvement and on-orbit debris removal. As most of on-orbit targets are non-cooperative, relatively accurate pose measurement is very essential for subsequent operations. However, with the rapid development of TriDAR, flash LIDAR and other laser scanning equipment in non-cooperative target measurement, it becomes more imperative to research methods for non-cooperative target pose tracking based on 3D point cloud feature. In this paper, a method for non-cooperative target pose tracking based on point cloud feature is proposed. Firstly, the target is identified using curvature, normal, density and other geometric features of the point cloud. Then the particle filter algorithm is used to recognize the position and orientation of the target being tracked by calculating the similarity of the point cloud features of two adjacent frames. Experimental results showed that the proposed method could effectively identify the features of non-cooperative targets and track their position and attitude.

  8. Thermal vision based intelligent system for human detection and tracking in mobile robot control system

    Directory of Open Access Journals (Sweden)

    Ćirić Ivan T.

    2016-01-01

    Full Text Available This paper presents the results of the authors in thermal vision based mobile robot control. The most important segment of the high level control loop of mobile robot platform is an intelligent real-time algorithm for human detection and tracking. Temperature variations across same objects, air flow with different temperature gradients, reflections, person overlap while crossing each other, and many other non-linearities, uncertainty and noise, put challenges in thermal image processing and therefore the need of computationally intelligent algorithms for obtaining the efficient performance from human motion tracking system. The main goal was to enable mobile robot platform or any technical system to recognize the person in indoor environment, localize it and track it with accuracy high enough to allow adequate human-machine interaction. The developed computationally intelligent algorithms enables robust and reliable human detection and tracking based on neural network classifier and autoregressive neural network for time series prediction. Intelligent algorithm used for thermal image segmentation gives accurate inputs for classification. [Projekat Ministarstva nauke Republike Srbije, br. TR35005

  9. RGBD Video Based Human Hand Trajectory Tracking and Gesture Recognition System

    Directory of Open Access Journals (Sweden)

    Weihua Liu

    2015-01-01

    Full Text Available The task of human hand trajectory tracking and gesture trajectory recognition based on synchronized color and depth video is considered. Toward this end, in the facet of hand tracking, a joint observation model with the hand cues of skin saliency, motion and depth is integrated into particle filter in order to move particles to local peak in the likelihood. The proposed hand tracking method, namely, salient skin, motion, and depth based particle filter (SSMD-PF, is capable of improving the tracking accuracy considerably, in the context of the signer performing the gesture toward the camera device and in front of moving, cluttered backgrounds. In the facet of gesture recognition, a shape-order context descriptor on the basis of shape context is introduced, which can describe the gesture in spatiotemporal domain. The efficient shape-order context descriptor can reveal the shape relationship and embed gesture sequence order information into descriptor. Moreover, the shape-order context leads to a robust score for gesture invariant. Our approach is complemented with experimental results on the settings of the challenging hand-signed digits datasets and American sign language dataset, which corroborate the performance of the novel techniques.

  10. Data concentrator with FPGA-based track reconstruction for the Belle II DEPFET pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Schnell, Michael; Dingfelder, Jochen; Marinas, Carlos [Physikalisches Institut, Universitaet Bonn (Germany)

    2013-07-01

    The innermost two layers of the Belle II vertex detector at the KEK facility in Tsukuba, Japan, will be covered by high-granularity DEPFET pixel sensors. The large number of pixels leads to a high data rate of around 60 Gbps, which has to be significantly reduced by the Data Acquisition System. For the data reduction the hit information of the surrounding Silicon strip Vertex Detector (SVD) is utilized to define so-called Regions of Interest (ROI). Only hit information of the pixels located inside these ROIs are saved. The ROIs for the Pixel Detector (PXD) are computed by reconstructing track segments from SVD data and back extrapolation to the PXD. A data reduction of up to a factor of 10 is intended to be achieved by this design. All the necessary processing stages, the receiving and multiplexing of the data from the SVD on 48 optical fibers, the track reconstruction and the definition of the ROIs, will be performed by the Data Concentrator. The planned hardware design is based on a distributed set of Advanced Mezzanine Cards (AMC) each equipped with a Field Programmable Gate Array (FPGA) chip and 4 optical transceivers. In this talk, the hardware and the FPGA-based tracking algorithm is introduced with some preliminary simulation results. In addition, the acquisition and pre-processing of the SVD data are discussed. The presentation concludes with an outlook on a distributed tracking design.

  11. Through-Wall Multiple Targets Vital Signs Tracking Based on VMD Algorithm

    Directory of Open Access Journals (Sweden)

    Jiaming Yan

    2016-08-01

    Full Text Available Targets located at the same distance are easily neglected in most through-wall multiple targets detecting applications which use the single-input single-output (SISO ultra-wideband (UWB radar system. In this paper, a novel multiple targets vital signs tracking algorithm for through-wall detection using SISO UWB radar has been proposed. Taking advantage of the high-resolution decomposition of the Variational Mode Decomposition (VMD based algorithm, the respiration signals of different targets can be decomposed into different sub-signals, and then, we can track the time-varying respiration signals accurately when human targets located in the same distance. Intensive evaluation has been conducted to show the effectiveness of our scheme with a 0.15 m thick concrete brick wall. Constant, piecewise-constant and time-varying vital signs could be separated and tracked successfully with the proposed VMD based algorithm for two targets, even up to three targets. For the multiple targets’ vital signs tracking issues like urban search and rescue missions, our algorithm has superior capability in most detection applications.

  12. CRITICAL ASSESSMENT: Gallium nitride based visible light emitting diodes

    OpenAIRE

    Oliver, Rachel A.

    2016-01-01

    This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by Maney Publishing. Solid state lighting based on light-emitting diodes (LEDs) is a technology with the potential to drastically reduce energy usage, made possible by the development of gallium nitride and its alloys. However, the nitride materials family exhibits high defect densities and, in the equilibrium wurtzite crystal phase, large piezo-electric and polarisation fields arising a...

  13. Monolithic white light emitting diodes using a (Ga,In)N-based light converter

    Science.gov (United States)

    Damilano, Benjamin; Lekhal, Kaddour; Kim-Chauveau, Hyonju; Hussain, Sakhawat; Frayssinet, Eric; Brault, Julien; Chenot, Sébastien; Vennéguès, Philippe; De Mierry, Philippe; Massies, Jean

    2014-03-01

    Commercially available inorganic white light emitting diodes (LEDs) are essentially based on the combination of a blue InGaN based LED chip covered by a long wavelength emitting (yellow, red) phosphor. We propose to avoid this step of phosphor deposition by taking advantage of the fact that yellow to red emission can be achieved using InGaN alloys. By stacking an InGaN/GaN multiple quantum well (QW) emitting in the yellow, acting as a light converter, and a short wavelength blue-violet pump LED grown on top, white light emission can be obtained. Furthermore, if we extend the emission spectrum of the light converter into the red, a warm white light color is demonstrated when a pump LED is grown on top. However, the high In content InGaN QWs of the light converter have a low thermal stability and the QW efficiency tends to degrade during the growth of the pump LED. Three different solutions are explored to avoid the thermal degradation of the light converter. The monolithic LED structures were grown by molecular beam epitaxy (MBE), by a combination of both MBE and metal-organic chemical vapor phase epitaxy (MOCVD), or by a low temperature full-MOCVD process. The best results are obtained using a complete MOCVD growth process. The structure and the MOCVD growth conditions are specifically adapted in order to avoid the thermal degradation of the large In composition InGaN QWs emitting at long wavelength during the growth of the subsequent layers.

  14. Light

    DEFF Research Database (Denmark)

    Prescott, N.B.; Kristensen, Helle Halkjær; Wathes, C.M.

    2004-01-01

    This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality......This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality...

  15. Multivariable Super Twisting Based Robust Trajectory Tracking Control for Small Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Xing Fang

    2015-01-01

    Full Text Available This paper presents a highly robust trajectory tracking controller for small unmanned helicopter with model uncertainties and external disturbances. First, a simplified dynamic model is developed, where the model uncertainties and external disturbances are treated as compounded disturbances. Then the system is divided into three interconnected subsystems: altitude subsystem, yaw subsystem, and horizontal subsystem. Second, a disturbance observer based controller (DOBC is designed based upon backstepping and multivariable super twisting control algorithm to obtain robust trajectory tracking property. A sliding mode observer works as an estimator of the compounded disturbances. In order to lessen calculative burden, a first-order exact differentiator is employed to estimate the time derivative of the virtual control. Moreover, proof of the stability of the closed-loop system based on Lyapunov method is given. Finally, simulation results are presented to illustrate the effectiveness and robustness of the proposed flight control scheme.

  16. A level-1 pixel based track trigger for the CMS HL-LHC upgrade

    CERN Document Server

    Moon, Chang-Seong

    2016-01-01

    We present feasibility studies to investigate the performance and interest of a Level-1 trigger based on pixels. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is based on real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of rare physics events from the large pile-up of events. The goal of adding the pixel information already at the real-time level of the selection is to help reducing the total Level-1 trigger rate while keeping a high selection capability. This is quite an innovative and challenging objective for the upgrade of the experiments for the High Luminosity LHC.

  17. Exploring hadronic tau identification with DC1 datat samples a track based approach

    CERN Document Server

    Richter-Was, Elzbieta; Tarrade, F

    2004-01-01

    In this note we discuss the identification of hadronic $\\tau$s. We propose an algorithm, tauID, which starts from a reconstructed, relatively high pT track and then collects calorimetric energy deposition in a fixed cone seeded by the track eta and phi at the vertex. With the proposed algorithm we explore exclusive features of the hadronic $\\tau$ decays and we indicate also the possibility of using an energy-flow based approach for defining the energy scale of the reconstructed tau-candidates. The results presented here are limited to the barrel region (|eta| < 1.5) and are based on the DC1 events simulated without pile-up and electronic noise. We compare the performances of the proposed algorithm and of the base-line tauRec algorithm and draw some conclusions for further studies.

  18. Incremental Structured Dictionary Learning for Video Sensor-Based Object Tracking

    Directory of Open Access Journals (Sweden)

    Ming Xue

    2014-02-01

    Full Text Available To tackle robust object tracking for video sensor-based applications, an online discriminative algorithm based on incremental discriminative structured dictionary learning (IDSDL-VT is presented. In our framework, a discriminative dictionary combining both positive, negative and trivial patches is designed to sparsely represent the overlapped target patches. Then, a local update (LU strategy is proposed for sparse coefficient learning. To formulate the training and classification process, a multiple linear classifier group based on a K-combined voting (KCV function is proposed. As the dictionary evolves, the models are also trained to timely adapt the target appearance variation. Qualitative and quantitative evaluations on challenging image sequences compared with state-of-the-art algorithms demonstrate that the proposed tracking algorithm achieves a more favorable performance. We also illustrate its relay application in visual sensor networks.

  19. A comparative study of artificial intelligent-based maximum power point tracking for photovoltaic systems

    Science.gov (United States)

    Hussain Mutlag, Ammar; Mohamed, Azah; Shareef, Hussain

    2016-03-01

    Maximum power point tracking (MPPT) is normally required to improve the performance of photovoltaic (PV) systems. This paper presents artificial intelligent-based maximum power point tracking (AI-MPPT) by considering three artificial intelligent techniques, namely, artificial neural network (ANN), adaptive neuro fuzzy inference system with seven triangular fuzzy sets (7-tri), and adaptive neuro fuzzy inference system with seven gbell fuzzy sets. The AI-MPPT is designed for the 25 SolarTIFSTF-120P6 PV panels, with the capacity of 3 kW peak. A complete PV system is modelled using 300,000 data samples and simulated in the MATLAB/SIMULINK. The AI-MPPT has been tested under real environmental conditions for two days from 8 am to 18 pm. The results showed that the ANN based MPPT gives the most accurate performance and then followed by the 7-tri-based MPPT.

  20. A level-1 pixel based track trigger for the CMS HL-LHC upgrade

    CERN Document Server

    CMS Collaboration

    2016-01-01

    We present feasibility studies to investigate the performances and interest of a Level-1 trigger based on pixels. The Level-1 (real-time) pixel based tracking trigger is a novel trigger system that is based on the real-time track reconstruction algorithms able to cope with very high rates and high flux of data in a very harsh environment. The pixel detector has an especially crucial role in precisely identifying the primary vertex of the rare physics events from the large pile-up (PU) of events. The goal of adding the pixel information already at the real-time level of the selection is to help reducing the total level-1 trigger rate while keeping an high selection capability. This is quite an innovative and challenging objective for the experiments upgrade for the High Luminosity LHC (HL-LHC).

  1. Optimal tracking of a sEMG based force model for a prosthetic hand.

    Science.gov (United States)

    Potluri, Chandrasekhar; Anugolu, Madhavi; Yihun, Yimesker; Jensen, Alex; Chiu, Steve; Schoen, Marco P; Naidu, D Subbaram

    2011-01-01

    This paper presents a surface electromyographic (sEMG)-based, optimal control strategy for a prosthetic hand. System Identification (SI) is used to obtain the dynamic relation between the sEMG and the corresponding skeletal muscle force. The input sEMG signal is preprocessed using a Half-Gaussian filter and fed to a fusion-based Multiple Input Single Output (MISO) skeletal muscle force model. This MISO system model provides the estimated finger forces to be produced as input to the prosthetic hand. Optimal tracking method has been applied to track the estimated force profile of the Fusion based sEMG-force model. The simulation results show good agreement between reference force profile and the actual force.

  2. Failure mode and effect analysis-based quality assurance for dynamic MLC tracking systems

    Energy Technology Data Exchange (ETDEWEB)

    Sawant, Amit; Dieterich, Sonja; Svatos, Michelle; Keall, Paul [Stanford University, Stanford, California 94394 (United States); Varian Medical Systems, Palo Alto, California 94304 (United States); Stanford University, Stanford, California 94394 (United States)

    2010-12-15

    Purpose: To develop and implement a failure mode and effect analysis (FMEA)-based commissioning and quality assurance framework for dynamic multileaf collimator (DMLC) tumor tracking systems. Methods: A systematic failure mode and effect analysis was performed for a prototype real-time tumor tracking system that uses implanted electromagnetic transponders for tumor position monitoring and a DMLC for real-time beam adaptation. A detailed process tree of DMLC tracking delivery was created and potential tracking-specific failure modes were identified. For each failure mode, a risk probability number (RPN) was calculated from the product of the probability of occurrence, the severity of effect, and the detectibility of the failure. Based on the insights obtained from the FMEA, commissioning and QA procedures were developed to check (i) the accuracy of coordinate system transformation, (ii) system latency, (iii) spatial and dosimetric delivery accuracy, (iv) delivery efficiency, and (v) accuracy and consistency of system response to error conditions. The frequency of testing for each failure mode was determined from the RPN value. Results: Failures modes with RPN{>=}125 were recommended to be tested monthly. Failure modes with RPN<125 were assigned to be tested during comprehensive evaluations, e.g., during commissioning, annual quality assurance, and after major software/hardware upgrades. System latency was determined to be {approx}193 ms. The system showed consistent and accurate response to erroneous conditions. Tracking accuracy was within 3%-3 mm gamma (100% pass rate) for sinusoidal as well as a wide variety of patient-derived respiratory motions. The total time taken for monthly QA was {approx}35 min, while that taken for comprehensive testing was {approx}3.5 h. Conclusions: FMEA proved to be a powerful and flexible tool to develop and implement a quality management (QM) framework for DMLC tracking. The authors conclude that the use of FMEA-based QM ensures

  3. 77 FR 38705 - Draft Specification for Airport Light Bases, Transformer Housings, Junction Boxes, and...

    Science.gov (United States)

    2012-06-28

    ... Federal Aviation Administration Draft Specification for Airport Light Bases, Transformer Housings... comment on the Draft ``Specification for Airport Light Bases, Transformer Housings, Junction Boxes, and... recommendations for airport light bases, transformer housings, junction boxes and accessories. The FAA has...

  4. Detailed analysis of latencies in image-based dynamic MLC tracking

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Per Rugaard; Cho, Byungchul; Sawant, Amit; Ruan, Dan; Keall, Paul J. [Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Department of Oncology and Department of Medical Physics, Aarhus University Hospital, 8000 Aarhus (Denmark); Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Department of Radiation Oncology, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States)

    2010-09-15

    Purpose: Previous measurements of the accuracy of image-based real-time dynamic multileaf collimator (DMLC) tracking show that the major contributor to errors is latency, i.e., the delay between target motion and MLC response. Therefore the purpose of this work was to develop a method for detailed analysis of latency contributions during image-based DMLC tracking. Methods: A prototype DMLC tracking system integrated with a linear accelerator was used for tracking a phantom with an embedded fiducial marker during treatment delivery. The phantom performed a sinusoidal motion. Real-time target localization was based on x-ray images acquired either with a portal imager or a kV imager mounted orthogonal to the treatment beam. Each image was stored in a file on the imaging workstation. A marker segmentation program opened the image file, determined the marker position in the image, and transferred it to the DMLC tracking program. This program estimated the three-dimensional target position by a single-imager method and adjusted the MLC aperture to the target position. Imaging intervals {Delta}T{sub image} from 150 to 1000 ms were investigated for both kV and MV imaging. After the experiments, the recorded images were synchronized with MLC log files generated by the MLC controller and tracking log files generated by the tracking program. This synchronization allowed temporal analysis of the information flow for each individual image from acquisition to completed MLC adjustment. The synchronization also allowed investigation of the MLC adjustment dynamics on a considerably finer time scale than the 50 ms time resolution of the MLC log files. Results: For {Delta}T{sub image}=150 ms, the total time from image acquisition to completed MLC adjustment was 380{+-}9 ms for MV and 420{+-}12 ms for kV images. The main part of this time was from image acquisition to completed image file writing (272 ms for MV and 309 ms for kV). Image file opening (38 ms), marker segmentation (4 ms

  5. Tracking of urban aerosols using combined lidar-based remote sensing and ground-based measurements

    Directory of Open Access Journals (Sweden)

    T.-Y. He

    2011-10-01

    Full Text Available A measuring campaign was performed over the neighboring towns of Nova Gorica in Slovenia and Gorizia in Italy on 24 and 25 May 2010, to investigate the concentration and distribution of urban aerosols. Tracking of two-dimensional spatial and temporal aerosol distributions was performed using scanning elastic lidar operating at 1064 nm. In addition, PM10 concentrations of particles, NOx and meteorological data were continuously monitored within the lidar scanning region. Based on the collected data, we investigated the flow dynamics and the aerosol concentrations within the lower troposphere and an evidence for daily aerosol cycles. We observed a number of cases with spatially localized increased lidar returns, which were found to be due to the presence of point sources of particulate matter. Daily aerosol concentration cycles were also clearly visible with a peak in aerosol concentration during the morning rush hours and daily maximum at around 17:00 Central European Time. We also found that the averaged horizontal atmospheric extinction within the scanning region 200 m above the ground is correlated to the PM10 concentration at the ground level with a correlation coefficient of 0.64, which may be due to relatively quiet meteorological conditions and basin-like terrain configuration.

  6. Discriminating between medium-sized Tridactyl Trackmakers: tracking Ornithopod tracks in the base of the Cretaceous (Berriasian, Spain.

    Directory of Open Access Journals (Sweden)

    Diego Castanera

    Full Text Available BACKGROUND: Recent work on the Jurassic-Cretaceous transition of the Iberian Range (Spain has opened a new window onto the interpretation of the trackmakers of some medium-sized tridactyl tracks. The ichnotaxon Therangospodus oncalensis has been described in the Huérteles Formation (Berriasian and is one of the classical tracks from the area assigned to medium-sized theropods. METHODOLOGY/PRINCIPAL FINDINGS: A review of the type locality of Therangospodus oncalensis (Fuentesalvo tracksite and other tracksites from the Huérteles Formation (Berriasian has yielded new information on the morphology, gait and trackmaker identity of the aforementioned ichnospecies. The new data suggest that the trackmaker is an ornithopod rather than a theropod on the basis of the length/width ratio, the anterior triangle length-width ratio, the short steps, the round to quadrangular heel pad impression and the probable manus impressions. CONCLUSIONS/SIGNIFICANCE: T. oncalensis shows similarities with various tracks from the Berriasian of Europe assigned to Iguanodontipus. The ichnotaxonomical status of this ichnospecies is here considered as Iguanodontipus? oncalensis due to the current state of knowledge of the ichnotaxonomy of medium-sized ornithopod tracks. This reassessment of I? oncalensis also has two significant implications for the palaeoecology of the faunas during the deposition of the Huérteles Formation: 1- the high number and percentage of theropod tracks would be lower than previous papers have suggested. 2- the gregarious behaviour described in the type locality (Fuentesalvo would be among ornithopods instead of theropods.

  7. Real-time visual tracking system modelling in MPSoC using platform based design

    Science.gov (United States)

    Jia, Zai Jian; Bautista, Tomás; Núñez, Antonio; Guerra, Cayetano; Hernández, Mario

    2009-02-01

    In this paper, we present the modelling of a real-time tracking system on a Multi-Processor System on Chip (MPSoC). Our final goal is to build a more complex computer vision system (CVS) by integrating several applications in a modular way, which performs different kind of data processing issues but sharing a common platform, and this way, a solution for a set of applications using the same architecture is offered and not just for one application. In our current work, a visual tracking system with real-time behaviour (25 frames/sec) is used like a reference application, and also, guidelines for our future CVS applications development. Our algorithm written in C++ is based on correlation technique and the threshold dynamic update approach. After an initial computational complexity analysis, a task-graph was generated from this tracking algorithm. Concurrently with this functionality correctness analysis, a generic model of multi-processor platform was developed. Finally, the tracking system performance mapped onto the proposed architecture and shared resource usage were analyzed to determine the real architecture capacity, and also to find out possible bottlenecks in order to propose new solutions which allow more applications to be mapped on the platform template in the future.

  8. A high-resolution tracking hodoscope based on capillary layers filled with liquid scintillator

    CERN Document Server

    Bay, A; Bruski, N; Buontempo, S; Currat, C; D'Ambrosio, N; Ekimov, A V; Ereditato, A; Fabre, Jean-Paul; Fanti, V; Frekers, D; Frenkel, A; Golovkin, S V; Govorun, V N; Harrison, K; Koppenburg, P; Kozarenko, E N; Kreslo, I E; Liberti, B; Martellotti, G; Medvedkov, A M; Mondardini, M R; Penso, G; Siegmund, W P; Vasilchenko, V G; Vilain, P; Wilquet, G; Winter, Klaus; Wörtche, H J

    2001-01-01

    Results are given on tests of a high-resolution tracking hodoscope based on layers of \\hbox{26-$\\mu$m-bore} glass capillaries filled with organic liquid scintillator (1-methylnaphthalene doped with R39). The detector prototype consisted of three 2-mm-thick parallel layers, with surface areas of $2.1 \\times 21$~cm$^2$. The layers had a centre-to-centre spacing of 6~mm, and were read by an optoelectronic chain comprising two electrostatically focused image intensifiers and an Electron-Bombarded Charge-Coupled Device (EBCCD). Tracks of cosmic-ray particles were recorded and analysed. The observed hit density was 6.6~hits/mm for particles crossing the layers perpendicularly, at a distance of 1~cm from the capillaries' readout end, and 4.2~hits/mm for particles at a distance of 20~cm. A track segment reconstructed in a single layer had an rms residual of $\\sim$~20~$\\mu$m, and allowed determination of the track position in a neighbouring layer with a precision of $\\sim$~170~$\\mu$m. This latter value corresponded to...

  9. Track based alignment of the CMS silicon tracker and its implication on physics performance

    Energy Technology Data Exchange (ETDEWEB)

    Draeger, Jula

    2011-08-15

    In order to fully exploit the discovery potential of the CMS detector for new physics beyond the Standard Model at the high luminosity and centre-of-mass energy provided by the Large Hadron Collider, a careful calibration of the detector and profound understanding of its impact on physics performance are necessary to provide realistic uncertainties for the measurements of physics processes. This thesis describes the track-based alignment of the inner tracking system of CMS with the Millepede II algorithm. Using the combined information of tracks from cosmic rays and collisions taken in 2010, a remarkable local alignment precision has been reached that meets the design specification for most regions of the detector and takes into account instabilities of the detector geometry over time. In addition, the impact of the alignment of b tagging or the Z boson resonance are investigated. The latter is studied to investigate the impact of correlated detector distortions which hardly influence the overall solution of the minimisation problem but introduce biases in the track parameters and thus the derived physics quantities. The determination and constraint of these weak modes present the future challenge of the alignment task at CMS. (orig.)

  10. Mobile Target Tracking Based on Hybrid Open-Loop Monocular Vision Motion Control Strategy

    Directory of Open Access Journals (Sweden)

    Cao Yuan

    2015-01-01

    Full Text Available This paper proposes a new real-time target tracking method based on the open-loop monocular vision motion control. It uses the particle filter technique to predict the moving target’s position in an image. Due to the properties of the particle filter, the method can effectively master the motion behaviors of the linear and nonlinear. In addition, the method uses the simple mathematical operation to transfer the image information in the mobile target to its real coordinate information. Therefore, it requires few operating resources. Moreover, the method adopts the monocular vision approach, which is a single camera, to achieve its objective by using few hardware resources. Firstly, the method evaluates the next time’s position and size of the target in an image. Later, the real position of the objective corresponding to the obtained information is predicted. At last, the mobile robot should be controlled in the center of the camera’s vision. The paper conducts the tracking test to the L-type and the S-type and compares with the Kalman filtering method. The experimental results show that the method achieves a better tracking effect in the L-shape experiment, and its effect is superior to the Kalman filter technique in the L-type or S-type tracking experiment.

  11. Three-dimensional object tracking based on perspective scale invariant feature transform correspondences

    Science.gov (United States)

    Chen, Wei; Liang, Luming; Zhao, Yuelong; Chen, Shu

    2017-05-01

    Reconstructing three-dimensional (3-D) poses from matched feature correspondences is widely used in 3-D object tracking. The precision of correspondence matching plays a major role in the pose reconstruction. Without prior knowledge of the perspective camera model, state-of-the-art methods only deal with two-dimensional (2-D) planar affine transforms. An interest point's detector and descriptor [perspective scale invariant feature transform (SIFT)] is proposed to overcome the side effects of viewpoint changing, i.e., our detector is invariant to viewpoint changing. Perspective SIFT is detected by the SIFT approach, where the sample region is determined by projecting the original sample region to the image plane based on the established camera model. An iterative algorithm then modifies the pose of the tracked object and it generally converges to a 3-D perspective invariant point. The pose of the tracked object is finally estimated by the combination of template warping and perspective SIFT correspondences. Thorough evaluations are performed on two public databases, the Biwi Head Pose dataset and the Boston University dataset. Comparisons illustrate that the proposed keypoint's detector largely improves the tracking performance.

  12. Development and validation of a prototypal neural networks-based tumor tracking method.

    Science.gov (United States)

    Seregni, M; Pella, A; Riboldi, M; Baroni, G

    2011-01-01

    In radiotherapy, intra-fractional organ motion introduces uncertainties in target localization, leading to unacceptable inaccuracy in dose delivery. Especially in highly selective treatments, such as those delivered with particles beams instead of photons, organ motion may results in severe side effects and/or limited tumor control. Tumor tracking is a motion mitigation strategy that allows an almost continuous dose delivery while the beam is dynamically steered to match the position of the moving target in real-time. Currently, tumor tracking is applied clinically only in the CyberKnife system for photon radiotherapy, whereas neither clinical solutions nor dedicated methodologies are available for particle therapy. Consequently, the aim of the proposed study is to develop a neural networks-based prototypal tracking algorithm intended for particle therapy. We developed a method that exploits three independent neural networks to estimate the internal target position as a function of external surrogate signals. This method was tested on data relative to 20 patients treated with CyberKnife, whose performance was used as benchmark. Results show that the developed algorithm allows targeting error reduction with respect to the CyberKnife system, thus proving the potential value of artificial neural networks for the implementation of tumor tracking methodologies.

  13. III-nitride based light emitting diodes and applications

    CERN Document Server

    Han, Jung; Amano, Hiroshi; Morkoç, Hadis

    2013-01-01

    Light emitting diodes (LEDs) are already used in traffic signals, signage lighting, and automotive applications. However, its ultimate goal is to replace traditional illumination through LED lamps since LED lighting significantly reduces energy consumption and cuts down on carbon-dioxide emission. Despite dramatic advances in LED technologies (e.g., growth, doping and processing technologies), however, there remain critical issues for further improvements yet to be achieved for the realization of solid-state lighting. This book aims to provide the readers with some contemporary LED issues, which have not been comprehensively discussed in the published books and, on which the performance of LEDs is seriously dependent. For example, most importantly, there must be a breakthrough in the growth of high-quality nitride semiconductor epitaxial layers with a low density of dislocations, in particular, in the growth of Al-rich and and In-rich GaN-based semiconductors. The materials quality is directly dependent on th...

  14. MIKE's PET: A participant-based experiment tracking tool for HCI practitioners using mobile devices

    Science.gov (United States)

    Mohamedally, Dean; Edlich, Stefan; Klaus, Enrico; Zaphiris, Panayiotis

    2006-02-01

    Knowledge Elicitation (KE) methods are an integral part of Human Computer Interaction (HCI) practices. They are a key aspect to the synthesis of psychology empirical methods with requirements engineering, User Centred Design (UCD) and user evaluations. Examples of these methods include prototyping, focus groups, interviews, surveys and direct video observation. The MIKE project (Mobile Interactive Knowledge Elicitation) at the Centre for HCI Design, City University London, UK provides mobile cyberscience capabilities for HCI practitioners conducting such research while at stakeholder locations. This paper reports on the design and development of a new MIKE based tool, named PET, a Participant-based Experiment Tracking tool for HCI practitioners using Java-based (J2ME) mobile devices. PET integrates its user tracking techniques with the development of the second generation implementation of the CONKER (COllaborative Non-linear Knowledge Elicitation Repository) Web Service. We thus report further on CONKER v2.0's new capabilities developed to enable tighter collaboration and empirical data management between HCI practitioners, considering their UCD needs. The visualisation, tracking and recording of HCI participant-based datasets via PET is explored with close connectivity with the CONKER v2.0 Web Service, in order to provide mobile-web cyberscience for remote and local HCI practitioners.

  15. Poly(lactic-co-glycolic acid) encapsulated gadolinium oxide nanoparticles for MRI-based cell tracking.

    Science.gov (United States)

    Bennewitz, Margaret F; Williams, Simone S; Nkansah, Michael K; Shapiro, Erik M

    2013-06-01

    Superparamagnetic iron oxide particles have proven useful for cell tracking applications by monitoring cell transplantation and migration in living organisms. However, one perceived drawback is that these particles cause dark contrast in MRI, sometimes yielding confusion with other biological phenomena, which also yield dark contrast. To that end, researchers have investigated the use of gadolinium oxide (Gd2O3) based contrast agents for MRI-based cell tracking, as Gd2O3 has favorable r1 molar relaxivity. We synthesized Gd2O3 nanocrystals and encapsulated them within PLGA matrices to form approximatley to 150 nm nanoparticles. r1 was 1.9 mM(-1) sec(-1) and r2 was 8.4 mM(-1) sec(-1). Cell labeling with particles was well tolerated by cells except at very high doses. MRI of labeled cells showed that labeled cells could achieve both R1 and R2 enhancements due to the internalized particles. R2 enhancements were approximately to twice that of R1 enhancements suggesting the use of very short echo times when using Gd2O3 based contrast agents for MRI-based cell tracking.

  16. Improved light and temperature responses for light use efficiency based GPP models

    Directory of Open Access Journals (Sweden)

    I. McCallum

    2013-05-01

    Full Text Available Gross primary production (GPP is the process by which carbon enters ecosystems. Diagnostic models, based on the theory of light use efficiency (LUE have emerged as one method to estimate ecosystem GPP. However, problems have been noted particularly when applying global results at regional levels. We hypothesize that accounting for non-linear light response and temperature acclimation of daily GPP in boreal regions will improve model performance. To test this hypothesis, we have chosen four diagnostic models for comparison, namely: an LUE model (linear in its light response both with and without temperature acclimation and an LUE model and a big leaf model both with temperature acclimation and non-linear in their light response. All models include environmental modifiers for temperature and vapour pressure deficit (VPD. Initially, all models were calibrated against four eddy covariance sites within Russia for the years 2002–2004, for a total of 10 site years. Model evaluation was performed via 10-out cross-validation. This study presents a methodology for comparing diagnostic modeling approaches. Cross validation clearly demonstrates the improvement in model performance that temperature acclimation makes in modeling GPP at strongly temperature controlled sites in Russia. Additionally, the inclusion of a non-linear light response function is shown to further improve performance. Furthermore we demonstrate the parameterization of the big leaf model, incorporating environmental modifiers for temperature and VPD.

  17. FPGA-Based Tracklet Approach to Level-1 Track Finding at CMS for the HL-LHC

    Science.gov (United States)

    Bartz, Edward; Chaves, Jorge; Gershtein, Yuri; Halkiadakis, Eva; Hildreth, Michael; Kyriacou, Savvas; Lannon, Kevin; Lefeld, Anthony; Ryd, Anders; Skinnari, Louise; Stone, Robert; Strohman, Charles; Tao, Zhengcheng; Winer, Brian; Wittich, Peter; Zientek, Margaret

    2017-08-01

    During the High Luminosity LHC, the CMS detector will need charged particle tracking at the hardware trigger level to maintain a manageable trigger rate and achieve its physics goals. The tracklet approach is a track-finding algorithm based on a road-search algorithm that has been implemented on commercially available FPGA technology. The tracklet algorithm has achieved high performance in track-finding and completes tracking within 3.4 μs on a Xilinx Virtex-7 FPGA. An overview of the algorithm and its implementation on an FPGA is given, results are shown from a demonstrator test stand and system performance studies are presented.

  18. Fiber based polarization filter for radially and azimuthally polarized light.

    Science.gov (United States)

    Jocher, Christoph; Jauregui, Cesar; Voigtländer, Christian; Stutzki, Fabian; Nolte, Stefan; Limpert, Jens; Tünnermann, Andreas

    2011-09-26

    We demonstrate a new fiber based concept to filter azimuthally or radially polarized light. This concept is based on the lifting of the modal degeneracy that takes place in high numerical aperture fibers. In such fibers, the radially and azimuthally polarized modes can be spectrally separated using a fiber Bragg grating. As a proof of principle, we filter azimuthally polarized light in a commercially available fiber in which a fiber Bragg grating has been written by a femtosecond pulsed laser. © 2011 Optical Society of America

  19. Neurochip Based on Light-addressable Potentiometric Sensor

    Institute of Scientific and Technical Information of China (English)

    Qingjun Liu; Hua Cai; Ying Xu; Lifeng Qin; Lijiang Wang; Ping Wang

    2006-01-01

    A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed. Using its light addressable characteristic. The problems of the limitations of restricted discrete active sites of current neurochips, such as microelectrode array and field effect transistor array can be settled easily. Based on the theoretical analysis of the interface between cells and LAPS, spontaneously discharges of hippocampal neurons induced by Mg2+-free media treatment were recorded by LAPS. The results demonstrate that this kind of neurochip has potential to monitor electrophysiology of cultured cells in a non-invasive way.

  20. Image Analysis of Fabric Pilling Based on Light Projection

    Institute of Scientific and Technical Information of China (English)

    陈霞; 黄秀宝

    2003-01-01

    The objective assessment of fabric pilling based on light projection and image analysis has been exploited recently.The device for capturing the cross-sectional images of the pilled fabrics with light projection is elaborated.The detection of the profile line and integration of the sequential cross-sectional pilled image are discussed.The threshold based on Gaussian model is recommended for pill segmentation.The results show that the installed system is capable of eliminating the interference with pill information from the fabric color and pattern.