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2011 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2011

作者： Magdics, Milán Szirmay-Kalos, László Tóth, Balázs Légrády, Dávid Cserkaszky, Áron Balkay, László Domonkos, Balázs Völgyes, Dávid Patay, Gergely Major, Péter Lantos, Judit Bükki, Tamás Department of Control Engineering and Information Technology Budapest University of Technology and Economics Hungary Institute of Nuclear Techniques Budapest University of Technology and Economics Hungary Institute of Nuclear Medicine University of Debrecen Hungary Mediso Medical Imaging Systems Ltd. Budapest Hungary

ISBN: (纸本)9781467301183

In positron emission tomography (PET), photon scattering inside the body causes significant blurring and quantification error in the reconstructed images. To solve this problem we have developed Monte Carlo (MC) based 3D PET reconstruction algorithms implemented on the Graphics processing Unit (GPU). Our implementation takes multiple Compton scattering into account without any significant additional cost. The performance of the scatter correction is evaluated using GATE simulation as well as by comparing reconstruction results of Tera-Tomo to the reference reconstruction implementation of the Philips Gemini TOF PET which applies attenuation correction and single scatter simulation (SSS) for scatter correction. The comparative reconstruction results are based on the NEMA NU2-2007 image quality phantom. © 2011 IEEE.

关键词： Positron emission tomography

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2D and 3D palmprint information and hidden Markov model for improved identification performance

2D and 3D palmprint information and hidden Markov model for ...

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2011 11th International Conference on Intelligent systems Design and Applications, ISDA'11

作者： Meraoumia, Abdallah Chitroub, Salim Bouridane, Ahmed Signal and Image Processing Laboratory Electronics and Computer Science Faculty USTHB P.O. box 32 El Alia Bab Ezzouar 16111 Algiers Algeria School of Computing Engineering and Information Sciences Northumbria University Pandon Building Newcastle upon Tyne United Kingdom Department of Computer Science King Saudi University P.O. Box 2454 Riyadh 11451 Saudi Arabia

ISBN: (纸本)9781457716751

Biometric systems based on a single source of information suffer from limitations such as the lack of uniqueness, non-universality of the chosen biometric trait, noisy data and spoof attacks. Multibiometrics are relatively new systems that overcome those problems. These systems fuse information from multiple biometric sources in order to achieve better identification performance. In this paper, 2D and 3D palmprint are integrated in order to construct an efficient multibiometric identification system based on matching score level fusion. For that, the texture information is characterized by the rotation invariant VARiance measures (VAR) and compressed using the Principal Components Analysis (PCA). Subsequently, we use the Hidden Markov Model (HMM) for modeling the feature vector of each palmprint. Finally, Log-likelihood scores are used for palmprint evaluation. The proposed scheme is tested and evaluated using PolyU 2D-3D palmprint database of 250 users. Our experimental results show the effectiveness and reliability of the proposed system, which brings high identification accuracy rate. © 2011 IEEE.

关键词： Principal component analysis

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GPU-Based Architectures and Their Benefit for Accurate and Efficient Wireless Network simulations

GPU-Based Architectures and Their Benefit for Accurate and E...

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International Symposium on modeling, Analysis and simulation of Computer and Telecommunication systems (MASCOTS)

作者： Philipp Andelfinger Jens Mittag Hannes Hartenstein Steinbuch Centre of Computing Karlsruhe Institute of Technology Germany Institute of Telematics Karlsruhe Institute of Technology Germany

In recent years, a trend towards the usage of physical layer models with increased accuracy can be observed within the wireless network community. This trend has several reasons. The consideration of signals - instead of packets - as the smallest unit of a wireless network simulation enables the ability to reflect complex radio propagation characteristics properly, and to study novel PHY/MAC/NET cross-layer optimizations that were not directly possible before, e.g. cognitive radio networks and interference cancellation. Yet, there is a price to pay for the increase of accuracy, namely a significant decrease of runtime performance due to computationally expensive signal processing. In this paper we study whether this price can be reduced - or even eliminated - if GPU-based signal processing is employed. In particular, we present and discuss four different architectures that can be used to exploit GPU-based signal processing in discrete event-based simulations. Our evaluation shows that the runtime costs can not be cut down completely, but significant speedups can be expected compared to a non GPU-based solution.

关键词： Graphics processing unit Computational modeling signal processing Wireless networks signal processing algorithms Computer architecture Runtime

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System-Level performance evaluation of Very High Complexity Media Applications : A H264/AVC Encoder Case Study

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International Journal of Communications, Network and System Sciences 2011年第7期4卷 436-446页

作者： Hajer Krichene Zrida Abderrazek Jemai Ahmed C Ammari Mohamed Abid Computer & Embedded Systems Laboratory National School of Engineers of Sfax Sfax University LIP2 Laboratory Faculty of Science of Tunis Research Unit in Materials Measurements and Applications National Institute of Applied Sciences Carthage Univers

Given the substantially increasing complexity of embedded systems, the use of relatively detailed clock cycle-accurate simulators for the design-space exploration is impractical in the early design stages. Raising the abstraction level is nowadays widely seen as a solution to bridge the gap between the increasing system complexity and the low design productivity. For this, several system-level design tools and methodologies have been introduced to efficiently explore the design space of heterogeneous signal processing systems. In this paper, we demonstrate the effectiveness and the flexibility of the Sesame/Artemis system-level modeling and simulation methodology for efficient peformance evaluation and rapid architectural exploration of the increasing complexity heterogeneous embedded media systems. For this purpose, we have selected a system level design of a very high complexity media application;a H.264/AVC (Advanced Video Codec) video encoder. The encoding performances will be evaluated using system-level simulations targeting multiple heterogeneous multiprocessors platforms.

关键词： System-Level performance evaluation Embedded systems Design Space Exploration Tools the Sesame/Artemis Design Tool a Parallel H.264/AVC Video Encoder

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Development of flight simulation and head-up display system for ergonomics evaluation

Development of flight simulation and head-up display system ...

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Congress on image and signal processing, CISP

作者： Chunxia Ma Damin Zhuang Xaiaoru Wanyan Fan Deng School of Aeronautical Science and Engineering Beijing University of Aeronautics and Astronautics Beijing China

Aiming at the humanity design of the Head-up display (HUD) information display involved in the development of large passenger aircraft in China, a flight simulation model coupling by nineteen equations was set up, and also a HUD model driven by flight simulation equations was set up using GL Studio. Ergonomic experiment was performed combining with subjects, and the humanity of information display on the HUD model was analyzed according to the reaction times and correct rates of subjects. The experiment results showed that the flight simulation model can effectively simulate the take off, cruise, landing and other flight courses of the aircraft; the HUD model built based on GL Studio can effectively combine with the flight simulation model and can reflect the position, gesture and other information of each flight course of the aircraft dynamically in real time. The color matching and size of HUD information display character fit for human characteristics were obtained through the experiment of simulating flight operations by subjects and the analysis of experiment results.

关键词： Atmospheric modeling Mathematical model Equations Aircraft Aerospace simulation Green products Real time systems

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A SystemC AMS/TLM platform for CMOS video sensors

A SystemC AMS/TLM platform for CMOS video sensors

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Conference on Design and Architectures for signal and image processing

作者： Fabio Cenni Serge Scotti Emmanuel Simeu TIMA Laboratory Grenoble France STMicroelectronics Grenoble France

This work presents how an image acquisition system based on a CMOS image sensor (CIS) has been modeled by means of the recently standardized analog and mixed-signal (AMS) extension to the SystemC 1666 IEEE standard. Many optical and electrical effects at a high level of abstraction are described by the model while limiting the model complexity for making the model suitable to top-level simulations and performance analysis. A comparison among SystemC AMS models developed at different levels of abstraction is shown. The Sys-temC AMS model of the image sensor is supplied with input scenarios that mimic the scene captured by an image sensor inserted in a dark-box for tuning purposes. The model is integrated in a SystemC TLM platform that contains also the image signal processor (ISP) algorithms and a comparator between the detected image and the processed one. The resulting SystemC AMS/TLM platform demonstrates how the tight interaction between the SystemC AMS image sensor model and the SystemC TLM ISP model allows an early development/validation of the embedded software. simulation results are shown and future related works discussed.

关键词： Time domain analysis Time varying systems Mathematical model Arrays Computational modeling Sensor systems

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Learning dictionaries for local sparse coding in image classification

Learning dictionaries for local sparse coding in image class...

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Asilomar Conference on signals, systems & Computers

作者： Jayaraman J. Thiagarajan Andreas Spanias SenSIP Center School of ECEE Arizona State University Tempe AZ USA

ISBN: (纸本)9781467303217

Low dimensional embedding of data samples lying on a manifold can be performed using locally linear modeling. By incorporating suitable locality constraints, sparse coding can be adapted to modeling local regions of a manifold. This has been coupled with the spatial pyramid matching algorithm to achieve state-of-the-art performance in object recognition. In this paper, we propose an algorithm to learn dictionaries for computing local sparse codes of descriptors extracted from image patches. The algorithm iterates between a local sparse coding step and an update step that searches for a better dictionary. evaluation of the local sparse code for a data sample is simplified by first estimating its neighbors using the proposed distance metric and then computing the minimum ℓ 1 solution using only the neighbors. The proposed dictionary update ensures that the neighborhood of a training sample is not changed from one iteration to the next. simulation results demonstrate that the sparse codes computed using the proposed dictionary achieve improved classification accuracies when compared to using a K-means dictionary with standard image datasets.

关键词： Dictionaries Vectors Training Encoding Measurement signal processing algorithms Approximation algorithms

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performance evaluation of Beamforming Solutions for mmWave Wireless systems

Performance Evaluation of Beamforming Solutions for mmWave W...

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2011 IEEE Global Telecommunications Conference - GLOBECOM 2011

作者： Florian Perget Daniela Dragomirescu Martin Jacob Thomas Kurner Cicero Vaucher Robert Plana LAAS CNRS Toulouse France UPS INSA INP ISAE LAAS Université de Toulouse Toulouse France TU Braunschweig Institut für Nachrichtentechnik Brunswick Germany HTC 32 NXP-NL Eindhoven Netherlands

New ultra high data rate systems in the 60 GHz band, especially those targeting high definition video indoor transmission, have a strong requirement for Quality of Service to prevent link outage, and this has to be performed at the MAC level. This paper describes a new simulation platform for these ultra high data rate wireless systems. This new tool models the complete wireless system, including a ray tracing based channel model, smart antennas model, and a physical layer model suitable for MB-OFDM and Single Carrier basebands. In addition, it includes the modeling of RF front-end properties and a MAC layer with beamforming capability for Quality of Service. In this paper we also highlight one use case of this simulation tool as a mean to compare the performance impact of different antenna arrays in a high definition video streaming application.

关键词： Antenna arrays Wireless communication Array signal processing Data models Computational modeling Solid modeling

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On quantifying of learning creativity through simulation and modeling of swarm intelligence and Neural Networks

On quantifying of learning creativity through simulation and...

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IEEE Education Engineering (EDUCON)

作者： Hassan. M. Mustafa Turki F. Al-Somani Ayoub Al-Hamadi Computer Engineering Department Faculty of Engineering Al-Baha University Al-Baha Saudi Arabia Institute of Electronics Signal Processing and Communications (IESK) Otto-von-Guericke University of Magdeburg Magdeburg Germany

This research work presents a systematic investigational study of an interesting challenging phenomenon observed in natural world. Mainly, presented study concerned with conceptual interdisciplinary analysis and evaluation of quantified learning creativity phenomenon. Associated with diverse aspects of measurable behavioral learning performance. That's observed by two diverse natural biological systems' models (human & non-human creatures). Specifically, introduced study of two biological models consider comparison of quantified learning creativity phenomenon. That's observed during human interactive tutoring/learning processes with environment. Versus ecological behavioral learning of swarm intelligence agents (Ants), during performing foraging process. Furthermore, presented comparative study inspired by naturally realistic models of Artificial Neural Network (ANN) and Swarm Intelligence. Interestingly, obtained simulation and modeling results have announced that learning performance curves of either models behave with close similarity to each other. More precisely, analysis and evaluation of learning performance curves of two diverse biological models revealed that both obey exponentially decayed learning curves; following least mean square (LMS) error algorithm.

关键词： Biological system modeling Humans Artificial neural networks Computational modeling Brain models Mathematical model

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Emissivity retrievals from airborne infrared hyperspectral images coupled with visible to SWIR hyperspectral images

Emissivity retrievals from airborne infrared hyperspectral i...

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Workshop on Hyperspectral image and signal processing: Evolution in Remote Sensing, WHISPERS

作者： V. Achard J. Bourrely P. Carle Theorical and Applied Optics Department ONERA-The French AeroSpace Laboratory France Design and performance Evaluation of Systems Department ONERA-The French AeroSpace Laboratory France

Emissivity extraction from hyperspectral infrared data is a challenge as it is a under-determined problem, and particularly with noisy data. A new method for emissivity retrieval dedicated to hyperspectral data that cover infrared as well as reflective spectral domains has been developed to overcome difficulties related to noise. The method is derived from the EARTH (surface Emissivity, temperature and Atmosphere Retrievals from Thermal infrared Hyperspectral image) algorithm [1], but takes advantage of the abundance of spectral information in the reflective domain, by including a classification step in the emissivity retrieval process. The attributes considered in this step are the first principal components of the reflective image (in radiance or reflectance units) that contain rich spectral information, and the brightness temperatures computed on the infrared image after spectral binning that give information on surface temperature. A k-means classification is carried out. Infrared spectral radiances are then averaged in each class and atmospheric compensation, based on neural networks followed by surface temperature / emissivity separation (TES), based on spectral smoothness is achieved. The benefits of the classification step are demonstrated on AHS data. Then the method is applied on simulated noisy data. The accuracy on emissivity is clearly improved when compared to results obtained without classification step.

关键词： Hyperspectral imaging Noise Hypercubes Atmospheric modeling Materials Temperature sensors

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