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Iris recognition for partially occluded images: Methodology and sensitivity analysis

Eurasip Journal on Advances in Signal Processing 2007年 2007卷

作者： Poursaberi, A. Araabi, B.N. Department of Electrical and Computer Engineering Control and Intelligent Processing Center of Excellence University of Tehran P.O. Box 14395-515 Tehran Iran School of Cognitive Sciences Institute for Studies in Theoretical Physics and Mathematics P.O. Box 19395-5746 Tehran Iran

Accurate iris detection is a crucial part of an iris recognition system. One of the main issues in iris segmentation is coping with occlusion that happens due to eyelids and eyelashes. In the literature, some various methods have been suggested to solve the occlusion problem. In this paper, two different segmentations of iris are presented. In the first algorithm, a circle is located around the pupil with an appropriate diameter. The iris area encircled by the circular boundary is used for recognition purposes then. In the second method, again a circle is located around the pupil with a larger diameter. This time, however, only the lower part of the encircled iris area is utilized for individual recognition. Wavelet-based texture features are used in the process. Hamming and harmonic mean distance classifiers are exploited as a mixed classifier in suggested algorithm. It is observed that relying on a smaller but more reliable part of the iris, though reducing the net amount of information, improves the overall performance. Experimental results on CASIA database show that our method has a promising performance with an accuracy of99.31. The sensitivity of the proposed method is analyzed versus contrast, illumination, and noise as well, where lower sensitivity to all factors is observed when the lower half of the iris is used for recognition. Copyright © 2007 Hindawi Publishing Corporation. All rights reserved.

关键词： Image analysis

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Phase-remapping attack in practical quantum-key-distribution systems

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Physical Review A 2007年第3期75卷 032314-032314页

作者： Chi-Hang Fred Fung Bing Qi Kiyoshi Tamaki Hoi-Kwong Lo Center for Quantum Information and Quantum Control Department of Electrical & Computer Engineering and Department of Physics University of Toronto Toronto Ontario Canada NTT Basic Research Laboratories NTT Corporation 3-1 Morinosato Wakamiya Atsugi-Shi Kanagawa 243-0198 Japan and CREST JST Agency 4-1-8 Honcho Kawaguchi Saitama 332-0012 Japan

Quantum key distribution (QKD) can be used to generate secret keys between two distant parties. Even though QKD has been proven unconditionally secure against eavesdroppers with unlimited computation power, practical implementations of QKD may contain loopholes that may lead to the generated secret keys being compromised. In this paper, we propose a phase-remapping attack targeting two practical bidirectional QKD systems (the “plug-and-play” system and the Sagnac system). We showed that if the users of the systems are unaware of our attack, the final key shared between them can be compromised in some situations. Specifically, we showed that, in the case of the Bennett-Brassard 1984 (BB84) protocol with ideal single-photon sources, when the quantum bit error rate (QBER) is between 14.6% and 20%, our attack renders the final key insecure, whereas the same range of QBER values has been proved secure if the two users are unaware of our attack; also, we demonstrated three situations with realistic devices where positive key rates are obtained without the consideration of Trojan horse attacks but in fact no key can be distilled. We remark that our attack is feasible with only current technology. Therefore, it is very important to be aware of our attack in order to ensure absolute security. In finding our attack, we minimize the QBER over individual measurements described by a general POVM, which has some similarity with the standard quantum state discrimination problem.

关键词： UNCONDITIONAL SECURITY CRYPTOGRAPHY DISCRIMINATION PROTOCOL STATES PROOF

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The Design of humanoid Robot Arm based on Morphological and Neurological Analysis of Human Arm

The Design of humanoid Robot Arm based on Morphological and ...

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IEEE International Conference on Mechatronics and Automation

作者： Yongseon Moon Kwang Seok Lee Cheol-Ho Yun Tae-Uk Jung Nak Yong Ko Youngchul Bae School of Information Communication Sunchon National University Suncheon South Korea Gwangju research center Korea Institute of Industrial and Technology Gwangju South Korea Department of Control and Instrumentation Engineering Chosun University Gwangju South Korea Division of Electrical Electronic Communication Computer Engineering Chonnam National University Yeosu South Korea

In this paper, we analyzed and verified possibility and validity of overcoming present limitations of humanoid robot by using morphological and neurological analysis of human arm. Through design, implementation and performance evaluation of humanoid robot arm, we will be verifying applicability and effectiveness of humanoid robot arm system based on SERCOS network that fulfills the concept of opening, networking and modularizations that are progressive direction of future robot.

关键词： Humanoid robots Humans Service robots Unified modeling language Information analysis Communication industry Mechatronics Design automation Robotics and automation Moon

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The Design of humanoid Robot Arm based on Morphological and Neurological Analysis of Human Arm

The Design of humanoid Robot Arm based on Morphological and ...

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Annual Conference of Industrial Electronics Society

作者： Yongseon Moon Jinju Park Cheol-Ho Yun Nak Yong Ko Hong Sik Moon Youngchul Bae School of Information Communication Sunchon National University Suncheon South Korea Gwangju research center Korea Institute of Industrial and Technology Gwangju South Korea Department of Control and Instrumentation Engineering Chosun University Gwangju South Korea Division of Electrical-Electronic Communication Computer Engineering Chonnam National University Yeosu South Korea

In this paper, we analyzed and verified the possibility and validity of overcoming present limitations of humanoid robots by using morphological and neurological analysis of human arm. Through design, implementation and performance evaluation of humanoid robot arm, we will be verifying applicability and effectiveness of humanoid robot arm system based on SERCOS network which fulfills the concept of opening, networking and modularizations which are progressive direction of future robot. Moreover, we proposed design and analysis of a single joint module for humanoid robot.

关键词： Humanoid robots Humans Service robots Information analysis ISO standards Moon Design engineering Performance analysis Actuators Industrial Electronics Society

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Voltage Injection Based Initial Rotor Position Estimation Method for Three-Phase Star-Connected Switched Reluctance Machines

Voltage Injection Based Initial Rotor Position Estimation Me...

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2007 International Conference on Power Electronics and Drive Systems (PEDS 2007), vol.2

作者： P. Somsiri P. Champa P. Wipasuramonton K. Tungpimonrut P. Aree Department or Electrical Engineering Thammasat University Thailland Industrial Control and Automation Lab National Electronics and Computer Technology Center Thailand

This paper presents a simple method to determine the initial rotor position of a three-phase star-connected switched reluctance machine (SRM) at standstill without position and current sensors. The principle of the initial rotor position estimation is based on the stator inductance variation related to the actual rotor position. In the proposed method, only two narrow voltage pulse injections are applied in sequence. In this method the machine parameters and phase current detection are not required. The method is suitable for low-cost SRM-drive applications. The experimental results were carried out on a 6/4 poles three-phase SRM and show the satisfactory accuracy of the proposed initial rotor position estimation.

关键词： Switched reluctance motor Rotor position estimation Standstill

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Three-Phase Full-Bridge Converters Applied to Switched Reluctance Motor Drives with a Modified Switching Strategy

Three-Phase Full-Bridge Converters Applied to Switched Reluc...

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International Conference on electrical Machines and Systems 2007(ICEMS2007)(第十届国际电机与系统会议)

作者： P. Somsiri K. Tungpimonrut P. Aree Industrial Control and Automation Lab National Electronics and Computer Technology Center Thailand Industrial Control and Automation Lab National Electronics and Computer Technology Center Thailand Department of Electrical Engineering Thammasat University Thailand

This paper presents an improved switching strategy for three-phase full-bridge converters applied to switched reluctance motor (SRM) drives. The modified switching strategy is based on the idea that in every electrical cycle the two switches in same leg of the converter alternate their commutating without using dead time. This drive method has several advantages including low cost, compactness, no dead time required, reduced number of switching pulses, and consequently reduced switching loss. The proposed method is analyzed and the experimental is investigated on 1.5 kW, three-phase 6/4 poles SRM which is designed for small electric vehicles by using standard three-phase full-bridge converter. The experimental results have confirmed an acceptable performance of this proposed technique.

关键词： Switched reluctance motor three-phase fullbridge converter switching strategy two-phase excitation.

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NONPARAMETRIC ENTROPY-BASED COUPLED MULTI-SHAPE MEDICAL IMAGE SEGMENTATION

NONPARAMETRIC ENTROPY-BASED COUPLED MULTI-SHAPE MEDICAL IMAG...

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IEEE International Symposium on Biomedical Imaging

作者： Alireza Akhoundi-Asl Hamid Soltanian-Zadeh School of Cognitive Sciences Institute of Studies in Theoretical Physics and Mathematics Tehran Iran Control and Intelligent Processing Center of Excellence (CIPCE) School of Electrical and Computer Engineering University of Tehran Tehran Iran Image Analysis Laboratory Radiology Department Henry Ford Health System Detroit MI USA

ISBN: (纸本)9781424406715;1424406714

We propose a 3D nonparametric, entropy-based, coupled, multishape approach for the segmentation of subcortical brain structures in magnetic resonance images (MRI). Our method uses PCA to capture structures variability. Because of complex relationships of pose and shape of the coupled structures, we only use their shape and size relation. To this end, we apply separate registrations of the structures. For each structure, we consider a similarity transform using seven parameters. In addition, to generate most accurate results, we estimate probability density functions (pdf) iteratively. The proposed method minimizes an entropy-based energy function using quasi-Newton algorithm. To improve the results, we use analytical derivatives. Sample results are given for the segmentation of putamen, thalamus and caudate illustrating the impact of coupling on the accuracy of the results.

关键词： Biomedical imaging Image segmentation Shape Couplings Brain Magnetic resonance Magnetic resonance imaging Principal component analysis Probability density function Iterative algorithms

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A Simplified Variable Speed Switched Reluctance Motor Drive without Using Encoder

A Simplified Variable Speed Switched Reluctance Motor Drive ...

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International Conference on electrical Machines and Systems 2007(ICEMS2007)(第十届国际电机与系统会议)

作者： P. Jitkreeyarn K. Tungpimolrut P. Somsiri S. Kachapornkul Akira Chiba Norimasa Tanabe Tadashi Fukao Industrial Control and Automation Laboratory National Electronics and Computer Technology Center Department of Electrical Engineering Faculty of Science and Technology Tokyo University of Science

The switched reluctance motor (SRM) and drive system is a candidate in various applications including the home appliance. The simple and low cost system with an adequate performance is also one topic to be developed. A speed sensor directly increases the cost and it directly influences the reliability of the system. This paper proposes a simplified variable speed control system for the SRM without using an encoder. The method is not based on the exact rotor position estimation, only the turn off angle is determined from the simple relation between measured terminal voltage and current. The effectiveness of the proposed method is verified by the experimental result on the 3 kW 3-phase 6-stator-pole and 4-rotor-pole SRM.

关键词： Switched reluctance motor variable speed drive system turn off angle rotor position estimation

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Single-photon quantum key distribution in the presence of loss

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Physical Review A 2007年第5期75卷 052336-052336页

作者： Marcos Curty Tobias Moroder Center for Quantum Information and Quantum Control Department of Physics and Department of Electrical & Computer Engineering University of Toronto Toronto Ontario Canada M5S 3G4 Institute for Quantum Computing University of Waterloo 200 University Avenue West Waterloo Ontario Canada N2L 3G1 Quantum Information Theory Group Institut für Theoretische Physik I and Max-Planck Research Group Institute of Optics Information and Photonics Universität Erlangen-Nürnberg D-91058 Erlangen Germany

We investigate two-way and one-way single-photon quantum key distribution (QKD) protocols in the presence of loss introduced by the quantum channel. Our analysis is based on a simple precondition for secure QKD in each case. In particular, the legitimate users need to prove that there exists no separable state (in the case of two-way QKD), or that there exists no quantum state having a symmetric extension (one-way QKD), that is compatible with the available measurements results. We show that both criteria can be formulated as a convex optimization problem known as a semidefinite program, which can be efficiently solved. Moreover, we prove that the solution to the dual optimization corresponds to the evaluation of an optimal witness operator that belongs to the minimal verification set of them for the given two-way (or one-way) QKD protocol. A positive expectation value of this optimal witness operator states that no secret key can be distilled from the available measurements results. We apply such analysis to several well-known single-photon QKD protocols under losses.

关键词： SEPARABILITY CRITERION NONORTHOGONAL STATES COHERENT STATES CRYPTOGRAPHY PROTOCOL DIFFERENTIATE SECURITY THEOREM PROOF

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A new architecture to execute CAs-based path-planning algorithm in mobile robots

A new architecture to execute CAs-based path-planning algori...

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2006 IEEE International Conference on Mechatronics, ICM

作者： Akbarimajd, Adel Lucas, Caro Robotics and AI Lab. Department of Electrical and Computer Engineering University of Tehran Iran Center of Excellence for Control and Intelligent Processing Department of Electrical and Computer Engineering University of Tehran Iran

ISBN: (纸本)0780397134

Several path-planning algorithms for mobile robots have been introduced. Proper architectures for mobile robots to implement the path-planning algorithms are also of interest. If the mobile robots are to perform complicated tasks including complex sensing and planning operations and have accepted performance, must be autonomous: capable of acquiring information and performing tasks without programmatic intervention. In this paper we employ a layered architecture for mobile robots to perform our previously introduced cellular automata based path planning technique. It employs an abstraction approach which makes the complexity manageable. The architecture has an important feature which is its internal artifacts;it has some beliefs about the world and these beliefs are represented in artifacts and most actions are planned and performed with respect to these artifacts © 2006 IEEE.

关键词： Algorithms

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