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Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

science china(Information sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2 & LONG KePing2 1 Research Center for Optical Internet and Mobile Information Networks(COIMIN),university of electronic science and technology of china,Chengdu 611731,china 2 School of Computer and Communications Engineering,university of science and technology Beijing,Beijing 100083,china 1. Research Center for Optical Internet and Mobile Information Networks (COIMIN) University of Electronic Science and Technology of China Chengdu 611731 China2. School of Computer and Communications Engineering University of Science and Technology Beijing Beijing 100083 China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

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ANALYSIS AND MEASUREMENT OF LARGE DYNAMIC RANGE RF SWITCH INTER-MODULATION

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Journal of electronics(china) 2008年第3期25卷 422-427页

作者： Han Zhouan Department of electronic Engineering the University of Electronic Science and Technology Chengdu 610054 China

Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic switch circuit and its inter-modulation, and studies in detail the measurement methods and systems of RF switch intercept point. It has provided cascaded simulation testing methods, which can accurately measure the PF switch, of which the second or third order intercept point value is above 75dB and 60dB, respectively. As the testing results are consistent with the theoretical analyses, it proves that the validity of the method satisfies the requirements of large scaled linearity measurement in engineering.

关键词： Large dynamic range Radio Frequency (RF) switch Intercept point Measurement

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Magnetic and dielectric properties of low temperature fired ferrite/ceramic composite materials

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Progress in Natural science:Materials International 2011年第1期21卷 21-26页

作者： Wei-wei LING~(1,2),Huai-wu ZHANG~1,Ying HE~1,Yuan-xun LI~1,Yun-yan WANG~1 1.State Key Laboratory of electronic Thin Films and Integrated Devices, university of electronic science and technology of china,Chengdu 610054,china 2.Department of Communication Engineering,Chengdu university of Information technology, Chengdu 610225,china [a] State Key Laboratory of electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China [b] Department of Communication Engineering Chengdu University of Information Technology Chengdu 610225 China

Ni-Cu-Zn ferrite/CaTiO3and Ni-Cu-Zn ferrite/BaTiO3composites which can be applied in low temperature co-fired ceramic（LTCC） technology were synthesized by conventional solid-state reaction at temperature lower than 950℃.Influence of the microstructures and the gap parameterδ/D on the complex permeability of the above two composites was *** modifiedδ/D values of the above two composites show a good fit to the magnetic circuit *** dielectric properties of the composites were predicted by the Maxwell-Garnctt effective medium theory and the discrepancy between measured and calculated values was analyzed.

关键词： ferrite/ceramic composite low temperature co-fired ceramic(LTCC) solid-state reaction magnetic properties dielectric properties

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A Method for Hierarchical Subband HDTV Splitting

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Journal of Systems Engineering and electronics 1995年第1期6卷 25-45页

作者： Feng Fan(university of electronic science and technology of china, Chengdu 610054, china)Wang Xincheng(Tsinghua university, Beijing 100084, china)Ignace Bruyland(university of Ghent, Sint-Pietersnieuwstraat 41, B-9000 Gent, Belgium) university of electronic science and technology of china Chengdu 610054 China Tsinghua university Beijing 100084 China university of Ghent Sint-Pietersnieuwstraat 41 B-9000 Gent Belgium

In this paper, an investigation is made on compatibility of the video formats TV (625/50/2:1/4:3), EDTV (625/50/1:1/16:9), HDTVint (1250/50/2:1/16:9) and HDTVpro(1250/50/2:1/16:9) in three-dimensional subband coding. A hierarchical method is proposed leading to a more reasonable joint solution for the issues of digital transmission evolution and interlace-to-progressive scanning conversion ill the frame work of bit rate compression. Conventional HDTVint with the diamond shaped spectrum is proposed to be replaced by a kind of 'switching'HDTVin signal which consists of three components and motion detection bits (MDB). The first component and the MDB represent TV. The first plus the second component and the MDB represent *** is splitted into switching HDTVint and extra component. The switching threshold and the length of temporal filter banks are discussed. Rearranging the pixels in subbands is recommended. Based on the proposed method, the transmission system can evolve through four steps: TV, EDTV, HDTVint and HDTVpro Results of bit rate compression are also presented. TV, EDTV, HDTVint and HDTVpro are compressed to approximately 40, 80, 128 and 256 Mbit/s respectively. Interlace scanning has drawbacks such as line flicker and line crawling as the eye follows the line structure in the picture. Progressive version switching TV and HDTVint can be reconstructed using one frame memory without the problems of handling temporal-vertical diamond shaped spectra of conventional TV and HDTVint based on a one-frame memory algorithm in the receiver.

关键词： video formats TV three-dimensional subband coding hierarchical subband HDTV splitting

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APPROXIMATE COMPLEX RAY ANALYSIS OF TWO-DIMENSIONAL RADOME

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Journal of electronics(china) 1990年第2期7卷 135-142页

作者：阮颖铮 university of electronic science and technology of china Chengdu

Electromagnetic transmission and scattering characteristics of radome may conve-niently be analyzed by complex ray paraxial approximation and collective ray *** anexample,a 2-D cylindrical single-layered dielectric radome is analyzed and calculated in this in-vestigation,including radome transmission coefficient,radar angular track performance and radarcross section of radomes,as well as the effect of ray parameters and antenna-radome parameterson computation *** is shown that this method can be used to simplify optimizations formany kinds of radomes.

关键词： Antenna Radome Electromagnetic scattering Complex ray

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NONUNIFORM CURRENTS ON A CONDUCTING WEDGE ILLUMINATED BY A TM PLANE WAVE

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Journal of electronics(china) 1990年第2期7卷 143-151页

作者：王秉中 university of electronic science and technology of china Chengdu

Closed-form expressions for nonuniform currents induced on a perfectly conductinginfinite wedge illuminated by a TM plane wave are *** computed by using theseexpressions are in good agreement with ones of the eigenfun... 详细信息

关键词： Plane waves Electromagnetic wave scattering Surface current

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Soft magnetic properties of (Ni_(50)Fe_(50)) SiO_2 granular thin films for high frequency application

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Rare Metals 2006年第z1期25卷 650-654页

作者： YANG Xiaolin GE Shihui RUAN Chengli College of Physics and electronic science University of Electronic Science and Technology of China Chengdu 610054 China Key Laboratory for Magnetism and Magnetic Materials of Ministry of EducationLanzhou University Lanzhou 730000 China College of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China

A series of (Ni50Fe50)x(SiO2)(1-x) films with different volume fraction x was fabricated by magnetron co-sputtering technique. The microstructure, magnetic and electrical properties were investigated systematically by using X-ray diffraction, transmission electronic microscope, vibrating sample magnetometer and the traditional four point measurement method of resistivity. The results show that the samples consist of nano-scaled Ni50Fe50 metallic particles with fcc structure uniformly embedded in amorphous insulating SiO2 matrix, and the particle size decreases with the decrease of x. The rapid change of coercivity with x is observed, and a minimum value 160 A·m-1 of Hc was obtained for the sample of x=0.83 with film thickness of 180 nm, which can be contributed to the exchange coupling between nano-scaled Ni50Fe50 particles. At the frequency lower than 1 GHz, the real part μ′ of complex permeability keeps about 110 and the image part μ″ is less than 15. Besides, this film exhibits high resistivity ρ=263 μΩ·cm, high saturation magnetization 4πMs=1.25 T, high in-plane magnetic anisotropy field Hk=6.37 kA·m-1, and the ferromagnetic resonance (FMR) frequency is estimated to be 2.8 GHz. Therefore, this film can be used in high frequency devices operating over 2 GHz.

关键词： thin films nanostructure magnetic properties

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The Queue Length Distribution for M/G/1 Queue with Delay Single Server Vacation

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Systems science and Systems Engineering 2000年第2期10卷 171-178页

作者： TANG Ying\|hui,\ TANG Xiao\|woSichuan university, Chengdu 610064 university of electronic science & technology of china, Chengdu 610054

In this paper we study the transient and equilibrium distributions of the queue length for the M/G/1 queueing system with delay single server *** the server busy period and the Laplace transformation we directly obtain the recursion formula of the L transformation of the transient queue length distribution at any time t , as well as the recursion formula of the equilibrium distribution for calculating *** we obtain the stochastic decompositions of the queue length and waiting time in equilibrium.

关键词： queue length transient distribution equilibrium distribution delay single server vacation

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Local segment-shared protection based on source egress gateway selection for multi-domain optical mesh networks

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science china(Information sciences) 2011年第2期54卷 227-235页

作者： ZHANG ShengFeng1,3, PENG YunFeng1,2, DU Shu1, YANG XiaoLong1,2 & LONG KePing1,2 1Research Center for Optical Internet and Mobile Information Networks, university of electronic science and technology of china, Chengdu 611731, china 2Institute of Advanced Network technology and New Serives (ANTS), university of science and technology Beijing, Beijing 100083, china 3Research Center for Optical Internet Networks, Chongqing university of Posts and Telecommunications, Chongqing 400065, china 1. Research Center for Optical Internet and Mobile Information Networks University of Electronic Science and Technology of China Chengdu 611731 China3. Research Center for Optical Internet Networks Chongqing University of Posts and Telecommunications Chongqing 400065 China2. Institute of Advanced Network Technology and New Serives (ANTS) University of Science and Technology Beijing Beijing 100083 China

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

关键词： survivability optical mesh networks multi-domains multiple failures segment-shared protection

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Quantum broadcast communication and authentication protocol with a quantum one-time pad

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Chinese Physics B 2014年第1期23卷 80-83页

作者：昌燕许春香张仕斌闫丽丽 School of Computer science and technology University of Electronic Science and Technology of China Department of Network Engineering Chengdu University of Information Technology

A quantum broadcast communication and authentication protocol with a quantum one-time pad based on the Greenberger-Horne-Zeilinger state is proposed. A binary string is used to express the identity of the receiver, which is encoded as a single sequence of photons. The encoded photon sequence acts as a detection sequence and implements au- thentication. An XOR operation serves as a one-time pad and is used to ensure the security of the protocol. The binary string is reused even in a noisy channel and proves to be unconditionally secure. In contrast with the protocols proposed by Wang et al. [Chin. Phys. 16 1868 （2007）] and Yang et al. [Chin. Phys. B 19 070304 （2010）], the protocol in this study implements the identity authentication with a reusable binary string; no hash function or local unitary operation is used. The protocol in this study is also easier to implement and highly efficient without losing security.

关键词： quantum broadcast communication quantum secure direct communication Greenberger–Horne–Zeilinger(GHZ) state authentication

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