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Spatial Solitons in 2D Graded-Index Waveguides with Different Distributed Transverse Diffractions

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communications in Theoretical Physics 2014年第2期61卷 214-220页

作者：陈翼翔 School of electronics Information Zhejiang University of Media and Communications

We discuss the nonlinear Schr6dinger equation with variable coefficients in 21） graded-index waveguides with different distributed transverse diffractions and obtain exact bright and dark soliton solutions. Based on these solutions, we mainly investigate the dynamical behaviors of solitons in three different diffraction decreasing waveguides with the hyperbolic, Gaussian and Logarithmic profiles. Results indicate that for the same parameters, the amplitude of bright solitons in the Logarithmic profile and the amplitude of dark solitons in the Gaussian profile are biggest respectively, and the amplitude in the hyperbolic profile is smallest, while the width of solitons has the opposite case.

关键词： nonlinear Schr6dinger equation bright solitons dark solitons diffraction decreasing waveguides

A new approach for modeling of dark current characteris-tics of quantum wire infrared photodetectors

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Optoelectronics Letters 2011年第4期7卷 260-262页

作者： H.Barickaby A.Zarifkar M.H.Sheikhi Department of communications and electronics Shiraz University

In order to study the dark current characteristics in a quantum wire infrared photodetector(QRIP),the average number of electrons in quantum wires(QRs) must be got,which is mostly too *** this paper we give a simple formula to calculate the average number of carriers in a quantum wire(QR) that can be easily evaluated by mathematical softwares,and then we use this formula to study dark current characteristics of a quantum wire infrared photodetector(QRIP).

关键词：暗电流特性红外探测器量子线建模软件评估平均数 QRS 运营商

Parallel Optimization of Program Instructions Using Genetic Algorithms

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Computers, Materials & Continua 2021年第6期67卷 3293-3310页

作者： Petre Anghelescu partment of electronics Communications and ComputersUniversity of PitestiPitesti110040Romania

This paper describes an efficient solution to parallelize softwareprogram instructions, regardless of the programming language in which theyare written. We solve the problem of the optimal distribution of a set ofinstructions on available processors. We propose a genetic algorithm to parallelize computations, using evolution to search the solution space. The stagesof our proposed genetic algorithm are: The choice of the initial populationand its representation in chromosomes, the crossover, and the mutation operations customized to the problem being dealt with. In this paper, geneticalgorithms are applied to the entire search space of the parallelization ofthe program instructions problem. This problem is NP-complete, so thereare no polynomial algorithms that can scan the solution space and solve theproblem. The genetic algorithm-based method is general and it is simple andefficient to implement because it can be scaled to a larger or smaller number ofinstructions that must be parallelized. The parallelization technique proposedin this paper was developed in the C# programming language, and our resultsconfirm the effectiveness of our parallelization method. Experimental resultsobtained and presented for different working scenarios confirm the theoreticalresults, and they provide insight on how to improve the exploration of a searchspace that is too large to be searched exhaustively.

关键词： Parallel instruction execution parallel algorithms genetic algorithms parallel genetic algorithms artificial intelligence techniques evolutionary strategies

Reservation-based dynamic admission control scheme for wideband code division multiple access systems

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Journal of Central South University 2012年第2期19卷 393-401页

作者： A.Y.Al-nahari S.A.El-Dolil M.I.Dessouky F.E.Abd El-Samie Department of electronics and Electrical communications Faculty of Electronic EngineeringMenoufia University

Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDMA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using Markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme.

关键词： admission control resource reservation wideband code division multiple access resource utilization

Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm-Based Clustering Scheme for Augmenting Network Lifetime in WSNs

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China communications 2024年第9期21卷 159-178页

作者： N Tamilarasan SB Lenin P Mukunthan NC Sendhilkumar Department of electronics and communications Engineering Sri Indu College of Engineering and TechnologyHyderabadTelanganaIndia Department of electronics and communications Engineering Sri Manakula Vinayagar Engineering CollegePondicherryIndia

In Wireless Sensor Networks(WSNs),Clustering process is widely utilized for increasing the lifespan with sustained energy stability during data *** clustering protocols were devised for extending network lifetime,but most of them failed in handling the problem of fixed clustering,static rounds,and inadequate Cluster Head(CH)selection criteria which consumes more *** this paper,Stochastic Ranking Improved Teaching-Learning and Adaptive Grasshopper Optimization Algorithm(SRITL-AGOA)-based Clustering Scheme for energy stabilization and extending network *** SRITL-AGOA selected CH depending on the weightage of factors such as node mobility degree,neighbour's density distance to sink,single-hop or multihop communication and Residual Energy(RE)that directly influences the energy consumption of sensor *** specific,Grasshopper Optimization Algorithm(GOA)is improved through tangent-based nonlinear strategy for enhancing the ability of global *** the other hand,stochastic ranking and violation constraint handling strategies are embedded into Teaching-Learning-based Optimization Algorithm(TLOA)for improving its exploitation ***,SR and VCH improved TLOA is embedded into the exploitation phase of AGOA for selecting better CH by maintaining better balance amid exploration and *** results confirmed that the proposed SRITL-AGOA improved throughput by 21.86%,network stability by 18.94%,load balancing by 16.14%with minimized energy depletion by19.21%,compared to the competitive CH selection approaches.

关键词： Adaptive Grasshopper Optimization Algorithm(AGOA) Cluster Head(CH) network lifetime Teaching-Learning-based Optimization Algorithm(TLOA) Wireless Sensor Networks(WSNs)

Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 413-419页

作者： SUN Yong-ping School of electronics and Information Zhejiang University of Media and Communications Hangzhou 310018 China

The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t）＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied.... 详细信息

关键词： third-order two-point boundary value problem monotone iterative method positive solution,existence iterative scheme

Feature-based Image Sequence Compression Coding

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High Technology Letters 2001年第2期7卷 31-33页

作者：周志权 Jia Shilou Department of electronics and communications Engineering Harbin Institute of Technology

A novel compressing method for video teleconference applications is presented. Semantic-based coding based on human image feature is realized, where human features are adopted as parameters. Model-based coding and the... 详细信息

关键词： Compression coding Model-based Feature-based

Time-domain modified DFT modulated filter banks for multi-carrier transceiver systems

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 57-62页

作者： SHAO Kai JI Xiang ZHUANG Ling WANG Guang-yu Chongqing Key Laboratory of Mobile communications Technology Chongqing University of Posts and Telecommunications Department of electronics and communications Engineering Tampere University of Technology

A time domain designing method is proposed for discrete Fourier transform （DFT） modulated filter banks （DFT-FBs） for application in multi-carrier transceiver systems. Instead of using the time-reversed pair limitation between the transmitting /receiving filter pair, the receiving filters in the proposed filter banks are derived from transmitting filters in accordance with the Moore-Penrose generalized inverse matrix. It can be freely obtained to design the transmitting prototype filter, which mainly affects the level of spectral containment. Furthermore, the symbol error rate （SER） performance of the proposed filter bank based trans-multiplexer with one tap equalizer is investigated in ideal channel and multi-path channel environments respectively. Simulation shows that the proposed approach can achieve significant SER reductions when square root raised cosine （RRC） prototype filter is used for comparing with the orthogonal frequency division multiplexing （OFDM） and the general DFT-FBs based applications.

关键词： time-domain matrix DFT filter banks perfect reconstruction filter bank multi-carrier (FBMC) systems transceiver

Improving the reconstruction efficiency of sparsity adaptive matching pursuit based on the Wilkinson matrix

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Frontiers of Information Technology & Electronic Engineering 2018年第4期19卷 503-512页

作者： Rasha SHOITAN Zaki NOSSAIR I.I.IBRAHIM Ahmed TOBAL Computer and Systems Department Electronic Research Institute electronics Communicationsand Computer DepartmentHelwan University

Sparsity adaptive matching pursuit(SAMP)is a greedy reconstruction algorithm for compressive sensing *** reconstructs signals without prior information of sparsity and presents better reconstruction performance for noisy signals compared to other greedy ***,SAMP still suffers from relatively poor reconstruction quality especially at high compression *** the proposed research,the Wilkinson matrix is used as a sensing matrix to improve the reconstruction quality and to increase the compression ratio of the SAMP ***,the idea of block compressive sensing(BCS)is combined with the SAMP technique to improve the performance of the SAMP *** simulations have been conducted to evaluate the proposed BCS-SAMP technique and to compare its results with those of several compressed sensing *** results show that the proposed BCS-SAMP technique improves the reconstruction quality by up to six decibels(d B)relative to the conventional SAMP *** addition,the reconstruction quality of the proposed BCS-SAMP is highly comparable to that of iterative ***,the computation time of the proposed BCS-SAMP is less than that of the iterative techniques,especially at lower measurement fractions.

关键词： Block compressive sensing Sparsity adaptive matching pursuit Greedy algorithm Wilkinson matrix