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International Symposium on information Processing in Sensor Networks (IPSN)

作者： Yin Wang Gaofeng Pan Zhiyu Huang MOE Key Lab for Information System Security TNLIST Tsinghua University Science and technology on communication information security control laboratory Chinese Academy of Sciences

ISBN: (纸本)9781479964703

Multi-hop time synchronization in wireless sensor networks (WSNs) is often time-consuming and error-prone due to random time-stamp delays for MAC layer access and unstable clocks of intermediate nodes. Constructive interference (CI), a recently discovered physical layer phenomenon, allows multiple nodes transmit and forward an identical packet simultaneously. By leveraging CI, we propose direct multihop (DMH) time synchronization by directly utilizing the time-stamps from the sink node instead of intermediate n-odes, which avoids the error caused by the unstable clock of intermediate nodes. DMH doesn't need decode the flooding time synchronization beacons. Moreover, DMH explores the linear regression technique in CI based time synchronization to counterbalance the clock drifts due to clock skews.

关键词： Synchronization Clocks Protocols Accuracy Interference Wireless sensor networks Relays

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Design of weak optical signal detection circuit

Design of weak optical signal detection circuit

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第四届国际自动化测试与仪器仪表学术会议

作者： Wang Hao Lv Yong Liu Lishuang Lang Xiaoping Beijing Information Science & Technology University Science and Technology on Electro-Optical Information Security Control Laboratory

The design based on avalanche photo diode(APD)is described in this paper to provide a extract the weak signal from the *** amplifying circuit based on negative feedback current input can realize high sensitivity,low noise amplifying,and the OPA657 chip is selected as the ***280 active low-pass filter is used to suppress high frequency noise effectively and the output signal to noise ratio(SNR) is improved by 5 *** theory analysis and the experiment results show that the minimum detection power of the circuit is about 1.9nW to the light of980nm.

关键词： weak optical detection pre-amplifier filter avalanche photo diode(APD)

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Design of temperature control system for blackbody radiation source based on TEC

Design of temperature control system for blackbody radiation...

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第四届国际自动化测试与仪器仪表学术会议

作者： Li Fei Lv Yong Liu Lishuang Lang Xiaoping Beijing Information Science and Technology University Science and Technology on Electro-Optical Information Security Control Laboratory

In order to ensure the stability of temperature of the blackbody radiation source,a high-performance,high-precision temperature control system is *** system is based on the thermo-electric cooler(TEC) which is controlled by ADN8830 *** temperature of the blackbody radiation source is sensed by the Pt100 thermistor,and then the temperature signal is converted into the voltage signal by the temperature transmitter to *** PID closed feedback loop is adopted for the temperature *** the test of the designed temperature control system,the result shows that the set-up time of this system is about 340 s and the temperature control accuracy is ±0.02 ℃.

关键词： PID ADN8830 thermo-electric cooler(TEC)

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A design of Rotman lens for phase antenna array

A design of Rotman lens for phase antenna array

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Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC)

作者： Wan Chen Jiahui Fu Qun Wu Jun Hua Department of Electronics and Communication Engineering Harbin Institute of Technology Harbin Heilongjiang China Science and Technology on Communication Information Security Control Laboratory Jiaxing Zhejiang China

In this work, a wide banded planar multi-input/output port Rotman lens for phase array antennas is investigated by simulation. The Rotman lens consists of lens and delay lines. With essential parameters, the outline of the lens is calculated by Matlab, in this way we can design a Rotman lens with certain functions, also the model is constructed by simulation software with the data imported from Matlab. The lens consists of the lens and the delay line. A useful segmented design of the delay line is applied to improve the transmission efficiency. A principle for dumpy port design is raised to improve the output characteristics. By this way, the magnitude error of different frequency is limited within 3 dB and below 5 dB when the port is changed. The lens offers a phase shift from -70 degree to +70 degree with a changeable step.

关键词： Lenses Arrays Delay lines Mathematical model Antenna arrays MATLAB Equations

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Identification of radio communication source with multi-object optimization

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Yingyong Kexue Xuebao/Journal of Applied sciences 2012年第6期30卷 559-565页

作者： Tang, Zhi-Ling Yang, Xiao-Niu Li, Jian-Dong School of Communication Engineering Xidian University Xi'an 710071 China School of Electronic Engineering and Automation Guilin University of Electronic Technology Guilin 541004 Guangxi Province China Science and Technology on Communication Information Security Control Laboratory Jiaxing 314033 Zhejiang Province China

To identify personality of a radio signal, a new method of multi-object optimization is proposed to solve a system of high order cumulants equations. The power amplifier model is first shown to be equivalent to a multi-input single-output system. A system of equations is derived from the cumulant relation between input and output. The system is solved with multi-object genetic optimization to obtain the features. The system of equations is verified by simulation, and the results of estimation are compared with computed values, showing that the proposed method can extract features from the received signal only with minor errors.

关键词： Radio communication

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A novel miniaturized band-pass frequency selective surface

A novel miniaturized band-pass frequency selective surface

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2012 5th Global Symposium on Millimeter-Waves, GSMM 2012

作者： Li, Wanlu Yang, Guohui Zhang, Tong Wu, Qun Hua, Jun Chen, Meiliang Gu, Xuemai School of Electronics and Information Technology Harbin Institute of Technology Harbin 150001 China Department of Microwave Engineering Key Laboratory No.92 West Dazhi Street Harbin 150001 China Fu Foundation School of Engineering and Applied Science Columbia University 116th Street and Broadway New York NY 10027 United States Science and Technology on Communication Information Security Control Laboratory Jiaxing Zhejiang Province 314033 China

ISBN: (纸本)9781467313032

In this paper, a novel band-pass miniaturized FSS is proposed, in which a unit cell consists of four spiral etched slot lines arranged central-symmetrically on a dielectric substrate, and the spiral elements are placed interlaced so that each element is connected to an adjacent one in another unit cell. Simulation results show the FSS has the dimension of a unit cell only 0.060λx0.060λ, where λ represents the wavelength corresponding to the resonant frequency. And the miniaturization is stable with respect to different polarizations and incident angles. Prototype of the FSS is fabricated and tested. The measured results show very good agreement with simulated ones. © 2012 IEEE.

关键词： Frequency selective surfaces

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BosonSampling with realistic single-photon sources

BosonSampling with realistic single-photon sources

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Conference on Lasers and Electro-Optics Europe

作者： Matthew A. Broome Alessandro Fedrizzi Saleh Rahimi-Keshari Agata M. Branczyk Justin Dove Scott Aaronson Timothy C. Ralph Andrew G. White Centre for Engineered Quantum Systems School of Mathematics and Physics University of Queensland Brisbane 4072 Australia Centre for Quantum Computer and Communication Technology School of Mathematics and Physics University of Queensland Brisbane 4072 Australia Department of Chemistry and Centre for Quantum Information and Quantum Control 80 St. George Street University of Toronto Toronto Ontario M5S 3H6 Canada Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of Technology Cambridge MA 02139 USA

ISBN: (纸本)9781479905942

The extended Church-Turing thesis posits that any computable function can be calculated efficiently by a probabilistic Turing machine. If this thesis held true, the global effort to build quantum computers might ultimately be unnecessary. The thesis would however be strongly contradicted by a physical device that efficiently performs a task believed to be intractable for classical computers. BosonSampling - the sampling from a distribution of n photons undergoing some linear-optical process - is a recently developed, experimentally accessible example of such a task [1].

关键词： Avalanche photodiodes Interference Nonlinear optical crystals Parametric down conversion Photons Quantum optics

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Distribution-aware mutation analysis

Distribution-aware mutation analysis

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36th Annual IEEE International Computer Software and Applications Conference Workshops, COMPSACW 2012

作者： Sun, Chang-Ai Wang, Guan Cai, Kai-Yuan Chen, Tsong Yueh School of Computer and Communication Engineering University of Science and Technology Beijing Beijing China Department of Automatic Control Beijing University of Aeronautics and Astronautics Beijing China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Science Beijing China Facuity of Information and Communication Technologies Swinburne University of Technology Melbourne VIC Australia

ISBN: (纸本)9780769547589

Mutation analysis is widely employed to evaluate the effectiveness of various software testing techniques. In most situations, mutation operators are uniformly applied to the original programs, while the faults tend to be clustered in practice. This may result in the inappropriate simulation of faults, and thus cannot deliver the reliable evaluation results. To overcome this, we propose a distribution-aware mutation analysis technique and conducted empirical studies to investigate the impact of the mutation distribution on the effectiveness evaluation of testing techniques. As an illustration, we select the commonly practiced random testing technique and two versions of dynamic random testing techniques and apply them to testing Web services. Results of empirical studies suggest that the mutation distribution significantly affects the evaluation results. This observation further indicates that the effectiveness of testing techniques previously evaluated with the uniform mutation analysis needs further realignments. © 2012 IEEE.

关键词： Software testing

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The relation on prefix hijacking and the internet hierarchy

The relation on prefix hijacking and the internet hierarchy

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6th International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing, IMIS 2012

作者： Zhao, Jinjing Wen, Yan Li, Xiang Peng, Wei Zhao, Feng Beijing Institute of System Engineering Beijing China National Key Laboratory of Science and Technology on Information System Security Beijing China Beijing Aerospace Control Center Beijing China National University of Defense Technology Computer School Changsha China

ISBN: (纸本)9780769546841

Border Gateway Protocol (BGP) is the de facto inter-domain routing protocol. There have been many incidents of IP prefix hijacking by BGP protocol in the Internet. Attacks may hijack victim's address space to disrupt network services or perpetrate malicious activities such as spamming and DoS attacks without disclosing identity. The relation on prefix hijacking and the Internet hierarchy is presented in this paper. The Internet is classified into three hierarchies based on the power-law and commercial relations of autonomous systems. The relation of network topology and prefix hijacking influence is presented for all sorts of hijacking events in different layers. The result shows that the hierarchical nature of network influences the prefix hijacking greatly. © 2012 IEEE.

关键词： Border Gateway Protocol

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Non-negative matrix factorization based on double sparsity K-SVD

Non-negative matrix factorization based on double sparsity K...

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第三届数字制造与自动化国际会议

作者： Zheng Hong Li Zhen Li Zhao School of Automation Science and Electrical Engineering Beihang University Science and Technology on Electro-Optical Information Security Control Laboratory

This paper presents a novel non-negative matrix factorization algorithm based on double sparsity K-SVD. It keeps the good parts-based representation. And meanwhile it has a well sparsity as sparse coding. The influences given by different initialization condition have been successfully overcome. Compared with other algorithms, the algorithm proposed is much faster. This dissertation demonstrates the advantages of the proposed algorithm by simulator experimentation.

关键词： double sparisity K-SVD non-negative matrix factorization

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