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Chinese Journal of electronics 2016年第3期25卷 577-582页

作者： ZHANG Jinling YANG Jinsheng ZHANG Hongxin school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing Vacuum electronics Research Institute

Based on the principle of phase velocity tapering or stepping output circuit, using the phase velocity variation of the output circuit, four kinds of nonuniform output circuit models have been presented in broadband helix Traveling-wave tubes(TWTs). Taking an example of6–18GHz, 100 W broadband helix TWT and using the improved one-dimensional large signal program, second harmonic suppression performances have been studied by calculating the quantitative relationship between fundamental efficiency, second harmonic output power, and the stepping(tapering) position and strength of phase velocity variation for the four kinds of nonuniform output circuits. From the research results of backward wave and second harmonic suppression feature in two kinds of nonuniform output circuits, we obtained the design principle of phase velocity stepping or tapering, which could suppress the Backward wave oscillation(BWO) and reduce the output power of second harmonic for broadband high-power helix TWTs.

关键词： Backward wave suppression Fundamental efficiency Nonuniform circuits Second harmonic suppression Traveling-wave tube(TWT)

Performance Tradeoff Between Energy Conservation and User Fairness for D2D Communication Underlaying Cellular Networks

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Chinese Journal of electronics 2017年第3期26卷 600-607页

作者： TANG Rui ZHAO Jihong QU Hua school of electronics and Information Engineering Xi'an Jiaotong University school of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Device-to-Device(D2D)communication is viewed as an emerging technology in the fifth generation systems to fully explore the proximate gain residing in local communicating *** the interference imposed to the existing Cellular links(C-link)should be addressed in the optimization for underlaid D2D links(D-link).There is a performance tradeoff between Energy conservation(EC)and the number of links with satisfied Quality-of-service(Qo S)requirement or System capacity(SC).We aim to weight the above tradeoff for D-links by specifying it into optimizing EC on the condition that SC is maximized and Qo S requirements of C-links are fully guaranteed.A threestage joint power control and channel assignment mechanism is proposed including feasibility check,SC maximization and greedy optimization for *** to numerical results,we illustrate the necessity to conduct our performance tradeoff and observe the gain when multiple resource variables are in elaborate cooperation.

关键词： Device-to-Device(D2D) communication Energy conservation User fairness Resource allocation

Anisotropic self-diffusion of fluorinated poly(methacrylate) in metal-organic frameworks assessed with molecular dynamics simulation

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Chinese Physics B 2017年第12期26卷 221-226页

作者：鲁桃徐彪叶飞宏周馨慧陆云清王瑾 school of Opto-Electronic Engineering Nanjing University of Posts and Telecommunications Key Laboratory for Organic electronics and Information Displays & Institute of Advanced Materials Nanjing University of Posts & Telecommunications school of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications

Utilizing the periodically structured metal-organic framework （MOF） as the reaction vessel is a promising technique to achieve the aligned polymer molecular chains, where the diffusion procedure of the polymer monomer inside MOF is one of the key mechanisms. To investigate the diffusion mechanism of fluorinated polymer monomers in MOFs, in this paper the molecular dynamics simulations combined with the density functional theory and the Monte Carlo method are used and the all-atom models of TFMA （trifluoroethyl methacrylate） monomer and two types of MOFs,[Zn2（BDC）2（TED）]n and[Zn2（BPDC）2（TED）]n, are established. The diffusion behaviors of TFMA monomer in these two MOFs are simulated and the main influencing factors are analyzed. The obtained results are as follows. First, the electrostatic interactions between TFMA monomers and MOFs cause the monomers to concentrate in the MOF channel, which slows down the monomer diffusion. Second, the anisotropic shape of the one-dimensional MOF channel leads to different diffusion speeds of monomers in different directions. Third, MOF with a larger pore diameter due to a longer organic ligand,[Zn2（BPDC）2（TED）]n in this paper, facilitates the diffusion of monomers in the MOF channel. Finally, as the number of monomers increases, the self-diffusion coefficient is reduced by the steric effect.

关键词： fluorinated polymer metal-organic framework self-diffusion coefficient molecular dynamics

A Novel Peak-to-Average Power Ratio Reduction Scheme via Tone Reservation in OFDM Systems

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China Communications 2017年第11期14卷 279-290页

作者： Jurong Bai Yong Li Wei Cheng Huimin Du Yanben Wang school of electronics and Information Northwestern Polytechnical University school of Electronic Engineering Xi'an University of Posts and Telecommunications

In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel.

关键词： orthogonal frequency division multiplexing peak-to-average power ratio tone reservation signal to clipping noise ratio

Accuracy for superposition of squeezed states in lossless and dissipative channel

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Science China(Physics,Mechanics & Astronomy) 2013年第3期56卷 593-599页

作者： XIE Duan PENG JinYe school of electronics and Information Northwestern Polytechnical University school of Electronic Engineering Xi'an University of Posts and Telecommunications

The analysis of accuracy for superposition of squeezed states(SSSs) in lossless and loss case has been performed in this *** lossless case,time accuracies of SSSs with mean photon number n s have a scaling of ns-2 in two limits of large and small *** the help of photon loss model,the dissipative channel will degrade accuracies has been *** the limit of large squeezing,the accuracy will slowly decrease with the reduction of *** the limit of small squeezing,time accuracy scales as 1/(η4ns2) and will decrease much faster along with decreases.

关键词： time accuracy quantum clock synchronization superposition of squeezed states

Multi-Strategy Improvement of Sparrow Search Algorithm for Cloud Manufacturing Service Composition

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Wuhan University Journal of Natural Sciences 2024年第4期29卷 323-337页

作者： ZHOU Liliang LI Ben YU Qing DAI Guilan ZHOU Guofu Tenth Research Institute China Electronics Technology Group CorporationChengdu 610000SichuanChina Department of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023JiangsuChina Research Institution of Information Technology Tsinghua UniversityBeijing 100084China school of Computer Science Wuhan UniversityWuhan 430072HubeiChina

In existing research,the optimization of algorithms applied to cloud manufacturing service composition based on the quality of service often suffers from decreased convergence rates and solution quality due to single-population searches in fixed spaces and insufficient information *** this paper,we introduce an improved Sparrow Search Algorithm(ISSA)to address these *** fixed solution space is divided into multiple subspaces,allowing for parallel searches that expedite the discovery of target *** enhance search efficiency within these subspaces and significantly improve population diversity,we employ multiple group evolution mechanisms and chaotic perturbation ***,we incorporate adaptive weights and a global capture strategy based on the golden sine to guide individual discoverers more ***,differential Cauchy mutation perturbation is utilized during sparrow position updates to strengthen the algorithm's global optimization *** experiments on benchmark problems and service composition optimization problems show that the ISSA delivers superior optimization accuracy and convergence stability compared to other *** results demonstrate that our approach effectively balances global and local search abilities,leading to enhanced performance in cloud manufacturing service composition.

关键词： cloud manufacturing service composition optimization quality of service sparrow search algorithm

Effects of Quantum Noise on Quantum Clock Synchronization

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Communications in Theoretical Physics 2012年第8期58卷 213-219页

作者：谢端彭进业 school of electronics and Information Northwestern Polytechnical University school of Electronic Engineering Xi'an University of Posts and Telecommunications

In laboratory environment, the channel apparatus will generate particular dominant quantum noise. The noise then will give rise to some errors during synchronization. In this work, the accuracies of one qubit transport protocol and entangled states transport protocol in the presence of noise have been studied. With the help of three important and familiar noise models, the quantum noise will degrade the accuracy has been proved. Due to the influence of quantum noise, the accuracy of entangled qubits decrease faster than that of one qubit. The entangled states will improve the accuracy in noise-free channel, and will degrade the accuracy in noise channel.

关键词： quantum communication quantum clock synchronization quantum noise synchronization accuracy

Design of ultra-compact wavelength splitter based on lithium niobate nanowire optical waveguides

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Optoelectronics Letters 2012年第1期8卷 17-20页

作者：陈明刘子晨 school of electronics Engineering Xi'an University of Posts and Telecommunications Wuhan Research Institute of Posts and telecommunications

A wavelength splitter with ultra-compact and simple structure is proposed and analyzed by using both plane wave expansion （PWE） method and finite difference time domain （FDTD） method. The device is based on directional coupling between two parallel lithium niobate （LiNbO3, LN） nanowire optical waveguides. The wavelength splitter with a coupling region length of 5 um can separate 1.3 um and 1.55 um wavelengths for corresponding outputs with transmittance higher than 97%.

关键词： Finite difference time domain method Nanowires

Chameleon all-but-one extractable hash proof and its applications

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Science China(Information Sciences) 2018年第9期61卷 327-334页

作者： Gang HAN Hui LI Baodong QIN Dong ZHENG school of electronics and Information Northwestern Polytechnical University national Engineering Laboratory for Wireless Security Xi'an University of Posts and Telecommunications State Key Laboratory of Cryptology

Dear editor,We will introduce the notion of chameleon All-ButOne Extractable Hash Proof(ABO-EHP)*** is a special kind of ABO-EHP[1]with a tag space T that comprises two branches,denoted by

关键词： EHP ABO CCA Chameleon all-but-one extractable hash proof and its applications PKE

Effect of Zr and C Co-doping on the Optical Properties and Electronic Structure of TiO_2

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Chinese Journal of Structural Chemistry 2011年第8期30卷 1115-1121页

作者：刘刚李德华张茹 school of electronics and Engineering Beijing University of Posts and Telecommunications College of Physics and Electronic Engineering Sichuan Normal University school of Mathematics and Physics Beijing University of Posts and Telecommunications

The systematic trends and effect introduced by Zr and C co-doping to TiO2 of electronic structure and optical properties of anatase TiO2 have been calculated by the plane-wave ultra-soft pseudopotential density functional theory （DFT） method within the generalized gradient approximation （GGA） for the exchange-correlation potential. Through the current calculations, the density of states （DOS）, energy band structure and optical absorption coefficients have been obtained for TiO2 and compared with the doped TiO2, and the influence of electronic structure and optical properties caused by Zr and C co-doping has been presented qualitatively together. The results revealed that the energy band gap has been decreased owing to the doped Zr and C, whereas the optical absorption coefficients have been increased in the region of 400～800 nm and a red shift of absorption band can be found. Accordingly, photo catalytic activity of TiO2 has been enhanced. The current calculations are in good agreement with the experimental data.

关键词： density functional theory doping electronic structure optical property