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Imaging Systems and Applications, ISA 2011

作者： Jung, Inhwa Xiao, Jianliang Malyarchuk, Viktor Lu, Chaofeng Li, Ming Liu, Zhuangjian Yoon, Jongseung Huang, Yonggang Rogers, John A. Department of Materials Science and Engineering Beckman Institute for Advanced Science and Technology Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign Urbana IL 61801 United States Department of Civil Engineering Zhejiang University Hangzhou Zhejiang 310058 China Department of Civil and Environmental Engineering Northwestern University Evanston IL 60208 United States State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Institute of High Performance Computing 1 Fusionopolis Way #16-16 Connexis 138632 Singapore Department of Mechanical Engineering Northwestern University Evanston IL 60208 United States

We present curvilinear imagers using photodetector arrays on elastomeric membranes, capable of reversible deformation into hemispherical shapes via hydraulics. Combining with tunable, fluidic plano-convex lenses yield... 详细信息

ISBN: (纸本)9781557529145

关键词： Arrays Detector arrays Image quality Photodetectors Thin films Zoom lenses

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RASS: A real-time, accurate and scalable system for tracking transceiver-free objects

RASS: A real-time, accurate and scalable system for tracking...

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IEEE International Conference on Pervasive computing and Communications (PerCom)

作者： Dian Zhang Yunhuai Liu Lionel M. Ni College of Software Shenzhen University China Department of Computer Science and Engineering Hong Kong University of Science and Technology Hong Kong China Shenzhen Institutes of Advanced Technology Chinese Academy and Sciences China Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiaotong University China

Transceiver-free object tracking is to trace a moving object without carrying any communication device in an environment where the environment is pre-deployed with some monitoring nodes. Among all the tracking technologies, RF-based technology is an emerging research field facing many challenges. Although we proposed the original idea, until now there is no method achieving scalability without sacrificing latency and accuracy. In this paper, we put forward a real-time tracking system RASS, which can achieve this goal and is promising in the applications like the safeguard system. Our basic idea is to divide the tracking field into different areas, with adjacent areas using different communication channels. So the interference among different areas can be prevented. For each area, three communicating nodes are deployed on the ceiling as a regular triangle to monitor this area. In each triangle area, we use a Support Vector Regression (SVR) model to locate the object. This model simulates the relationship between the signal dynamics caused by the object and the object position. It not only considers the ideal case of signal dynamics caused by the object, but also utilizes their irregular information. As a result it can reach the tracking accuracy to around 1m by just using three nodes in a triangle area with 4m in each side. The experiments show that the tracking latency of the proposed RASS system is bounded by only about 0.26s. Our system scales well to a large deployment field without sacrificing the latency and accuracy.

关键词： Accuracy Wireless communication Wireless sensor networks Interference Lead Synchronization Predictive models

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Signal sparse representation based on the peak transform and modulus maximum of wavelet coefficients

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Tamkang Journal of Science and engineering 2011年第3期14卷 217-224页

作者： Cen, Yi-Gang Xin, Rui Chen, Xiao-Fang Cen, Li-Hui Hu, Ming-Xing Chen, Shi-Ming Institute of Information Science Beijing Jiaotong University Beijing 100044 China Beijing Key Laboratory of Advanced Information Science and Network Technology Beijing 100044 China School of Information Science and Engineering Central South University Hunan Changsha 410083 China Centre for Medical Image Computing University College London United Kingdom School of Electrical and Electronic Engineering East China Jiao Tong University Jiangxi Nanchang 330013 China

It is now well-known that one can reconstruct sparse or compressible signals accurately from a very limited number of measurements. This technique is known as "compressed sensing" or "compressive sampling" (CS). A basic requirement of CS is that a signal should be sparse or it can be sparsely represented in some orthogonal bases. Based on the Peak Transform (PT) and modulus maximum of wavelet coefficients, a new algorithm was proposed for the signals that are non-sparse themselves and can not be sparsely represented by wavelet transform such as the Linear Frequency Modulated signal. According to this algorithm, K-sparse wavelet coefficients can be obtained. For the peak sequence produced by the Peak Transform, value expansion approach of reversible watermarking is exploited such that the peak sequence can be embedded into the measurements of the signal, which avoids increasing additional points for transmission. By using the Peak Transform and modulus maximum, non-sparse wavelet coefficients can be transformed into K-sparse coefficients, which improves the reconstruction result of CS. Simulation results showed that our proposed algorithm achieved better performance comparing with the original CS algorithm.

关键词： Compressed sensing

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Abnormal electron paths induced by Klein tunneling in graphene quantum point contacts

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Physical Review B 2011年第3期84卷 035426-035426页

作者： Rui Yang Liang Huang Ying-Cheng Lai Celso Grebogi School of Electrical Computer and Energy Engineering Arizona State University Tempe Arizona 85287 USA Institute of Computational Physics and Complex Systems and Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou University Lanzhou Gansu 730000 China Department of Physics Arizona State University Tempe Arizona 85287 USA Institute for Complex Systems and Mathematical Biology School of Natural and Computing Sciences King’s College University of Aberdeen Aberdeen United Kingdom

We study quantum transport in a general graphene system subject to external potential, a situation that can be expected in all kinds of future graphene-based electronic devices with quantum dots and quantum point contacts. We find that electrons tend to take on propagating paths due to Klein tunneling that have absolutely no counterpart in nonrelativistic quantum systems. Strikingly, such abnormal quantum paths can lead to an extreme type of fractal-like of conductance fluctuations, not seen previously in any quantum transport systems. This phenomenon has profound implications to the development of graphene based devices that require stable electronic properties.

关键词： ELECTRONIC systems QUANTUM electronics QUANTUM dots CATHODE rays LEPTONS (Nuclear physics)

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Phonons in Bi2S3 nanostructures: Raman scattering and first-principles studies

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Physical Review B 2011年第20期84卷 205330-205330页

作者： Yanyuan Zhao Kun Ting Eddie Chua Chee Kwan Gan Jun Zhang Bo Peng Zeping Peng Qihua Xiong Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Institute of High Performance Computing 1 Fusionopolis Way #16-16 Connexis Singapore 138632 School of Physical Science and Technology MOE Key Laboratory on Luminescence and Real-Time Analysis Southwest University Chongqing 400715 China Division of Microelectronics School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798

Bi2S3 has shown promise in thermoelectric and optoelectronic applications as well as biological and chemical sensors. We present here a comprehensive study on the lattice dynamics of Bi2S3 nanostructures probed by micro-Raman scattering spectroscopy and first-principles calculations. Bi2S3 nanowires are synthesized using a physical vapor transport method via a vapor-liquid-solid mechanism on silicon substrates. Oriented Bi2S3 nanosheets are also obtained on mica substrates. The structure of the nanowires is determined to be orthorhombic with a growth orientation of [110] by x-ray diffraction and high-resolution transmission electron microscopy. A Raman scattering study is conducted for as-prepared Bi2S3 nanostructures, in which 33, 38, 46, and 53 cm−1 phonon modes are observed for the first time. We find several modes to be very sensitive to excitation wavelength and power. First-principles calculations of orthorhombic Bi2S3 predict a series of Raman modes, in good agreement with our experiments. Phonon-dispersion curves of Bi2S3 are also presented, and the effect of Born effective charges on the longitudinal-optical–transverse-optical splitting at the zone center is taken into account.

关键词： OPTOELECTRONIC devices THERMOELECTRICITY CHEMICAL detectors RAMAN effect TRANSMISSION electron microscopy PHONONS

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Attribute-Based Signature with Policy-and-Endorsement Mechanism

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Journal of Computer Science & Technology 2010年第6期25卷 1293-1304页

作者：王怀习朱岩冯荣权 Stephen S.Yau LMAM School of Mathematical SciencesPeking University Electronic Engineering Institute Institute of Computer Science and Technology Peking University Key Laboratory of Network and Software Security Assurance (Peking University) Ministry of Education Information Assurance Center and School of Computing Informatics and Decision Systems Engineering Arizona State University

In this paper a new signature scheme,called Policy-Endorsing Attribute-Based Signature,is developed to correspond with the existing Ciphertext-Policy Attribute-Based *** signature provides a policy-and-endorsement *** this mechanism a single user,whose attributes satisfy the predicate,endorses the *** signature allows the signer to announce his endorsement using an access policy without having to reveal the identity of the *** security of this signature,selfless anonymity and existential unforgeability,is based on the Strong Diffie-Hellman assumption and the Decision Linear assumption in bilinear map groups.

关键词： cryptography fine-grained access control attribute-based signature policy-and-endorsement selfless anonymity existential unforgeability

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Convergence analysis of the adaptive finite element method with the red-green refinement

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Science China Mathematics 2010年第2期53卷 499-512页

作者： ZHAO XuYing 1, 3 , HU Jun 2,? & SHI ZhongCi 1 1 State key laboratory of Scientific and engineering computing, Institute of Computational Mathematics and Scientific/engineering computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China 2 key laboratory of Mathematics and Applied Mathematics (Peking University), Ministry of Education and School of mathematical Sciences, Peking University, Beijing 100871, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100190, China 1. State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Mathematics and Applied Mathematics (Peking University) Ministry of Education and School of Mathematical Sciences Peking University Beijing 100871 China

In this paper, we analyze the convergence of the adaptive conforming P 1 element method with the red-green refinement. Since the mesh after refining is not nested into the one before, the Galerkin-orthogonality does not hold for this case. To overcome such a difficulty, we prove some quasi-orthogonality instead under some mild condition on the initial mesh (Condition A). Consequently, we show convergence of the adaptive method by establishing the reduction of some total error. To weaken the condition on the initial mesh, we propose a modified red-green refinement and prove the convergence of the associated adaptive method under a much weaker condition on the initial mesh (Condition B).

关键词： red-green refinement adaptive finite element method convergence non-nested local refinement

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Image encryption algorithm based on DNA sequences for the big image

Image encryption algorithm based on DNA sequences for the bi...

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International Conference on Multimedia Information Networking and Security

作者： Zhou, Shihua Zhang, Qiang Wei, Xiaopeng School of Mechanical Engineering Dalian University of Technology Dalian China Key Laboratory of Advanced Design and Intelligent Computing Dalian University Ministry of Education Dalian China

ISBN: (纸本)9780769542584

With the fast development of Internet technology and information processing technology, the image is commonly transmitted via the Internet. People enjoy the convenience and shortcut, but people have to face to the obsession that the important image information in transmission is easily intercepted by unknown persons or hackers. In order to enhance the image information security, image encryption becomes an important research direction. An image encryption algorithm based on DNA sequences for the big image is presented in this paper. The main purpose of this algorithm is to reduce the big image encryption time. This algorithm is implemented by using the natural DNA sequences as main keys. The first part is the process of pixel scrambling. The original image is confused in the light of the scrambling sequence is generated by the DNA sequence. The second part is the process of pixel replacement. The pixel gray values of the new image and the one of the three encryption templates are generated by the other DNA sequence are XORed bit-by-bit in turn. The experimental result demonstrates that the image encryption algorithm is feasible and simple. Through performance analysis, this algorithm is robust against all kinds of attacks and owns higher security. © 2010 IEEE.

关键词： DNA sequences

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An image encryption algorithm based on DNA self-assembly technology

An image encryption algorithm based on DNA self-assembly tec...

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2010 IEEE International Conference on Intelligent computing and Intelligent Systems, ICIS 2010

ISBN: (纸本)9781424465835

DNA self-assembly that is fast developed in the fields of DNA computing and nano technology has become the focus of scientific fields. DNA self-assembly is a method that uses the characteristics of base-pair to form polyhedron or super molecular structure. This is a complex progress from disordered to well-ordered, from simple to complicated. This paper mainly introduces that the DNA self-assembly technology is applied into the image encryption. In this paper, we proposed a complete design scheme of DNA tiles that is suitable for the image encryption. The DNA tiles mainly include five types, namely DNA tiles of the plaintext, DNA tiles of the encryption, DNA tiles of the cipertext, DNA tiles of the key and DNA tiles of the decryption. Through a simulate example, the effect of the image encryption algorithm is shown. ©2010 IEEE.

关键词： Cryptography

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Multicast grooming algorithm in waveband switching optical networks

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Journal of Lightwave Technology 2010年第19期28卷 2856-2864页

作者： Guo, Lei Wang, Xingwei Cao, Jiannong Hou, Weigang Pang, Lan College of Information Science and Engineering Northeastern University Shenyang 110819 China Department of Computing Hong Kong Polytechnic University Hong Kong Hong Kong State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijing 100871 China

In optical Wavelength-Division-Multiplexing (WDM) networks, multicast becomes more and more popular to provide high-speed communication between one point and multiple points. At the same time, the ports of Optical Cross-Connect (OXC) are greatly enhanced with the increasing number of wavelengths in fibers, and then the waveband switching technique is proposed to save the ports and reduce the cost of OXC. However, current waveband grooming algorithms are all limited in unicast. To achieve the multicast communication and meanwhile save the ports of OXC, we need to solve the multicast grooming, routing and wavelength/waveband assignment problem which is the HP-hard. In this paper, we propose a heuristic algorithm named Integrated Multicast Waveband Grooming (IMWG) based on Multicast Layered Auxiliary Graph (MLAG) that includes a Virtual Topology Layer (VTL) and multiple Waveband-Plane Layers (WPLs) to support the single-hop, multi-hop and hybrid multicast waveband grooming. For each demand, IMWG first computes a single-hop or multi-hop grooming waveband-tree on VTL. If the grooming waveband-tree cannot be found on VTL, IMWG computes a new waveband-tree on WPL. If the new waveband-tree cannot be found on WPL, IMWG computes a hybrid grooming waveband-tree on MLAG. Simulation results show that, compared with other algorithms, IMWG is able to obtain better performances. © 2010 IEEE.

关键词： Multicasting

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