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Self-Trapping of Two Bose-Einstein Condensates with a Coupling Drive

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Chinese Physics Letters 2006年第6期23卷 1387-1390页

作者：邱建国 school of information and communication engineering North University of China Taiyuan 030051

We present an approximate analytical solution to the population imbalance of two-component Bose-Einstein condensate with the coupling drive. The dependence of the time evolution of self-trapping upon the radio frequency wave, the Rabi coupling frequency, the initial atom number and relative phase between two condensates are investigated. The lower radio frequency wave, the same atom number and initial relative phase between condensates are beneficial to observe the self-trapping.

关键词： DYNAMICS INTERFERENCE OSCILLATIONS PHASE GASES

Energy-efficient resource allocation for hybrid bursty services in multi-relay OFDM networks

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Science China(information Sciences) 2017年第10期60卷 169-186页

作者： Yuhao ZHANG Qimei CUI Ning WANG Yanzhao HOU Weiliang XIE school of information and communication engineering Beijing University of Posts and Telecommunications China Telecom Corporation Limited

In this paper, we propose mapped two-way water filling(MTWF) scheme to maximize energy efficiency(EE) for hybrid bursty services with quality of services(Qo S) requirements in two-way multirelay(TWMR) OFDM networks. The bursty traffic is first analyzed by strictly proved equivalent homogeneous Poisson process, based on which the Qo S requirements are converted into sum-rate constraints. The formulated non-convex EE maximization problem, including subcarrier assignment, relay selection(RS) and rate allocation, is NP-hard involving combinatorial optimization. To conduct optimal RS on each subcarrier without priori bursty traffic knowledge, we utilize some approximate relationships under high data rate demands to remove its dependence on two-way data rates, and simplify the whole optimization problem as well. After the optimal channel configuration is obtained, which only depends on channel conditions, subcarrier assignment is attained through elitist selection genetic algorithm(ESGA), and rate allocation of each service is fulfilled by deducing two-way water filling principle. A new equivalent optimization objective function is proposed next as the simple evaluating index in ESGA to reduce complexity. Finally, simulations are carried out to verify the superiority and convergence of our scheme, as well as the applicability for different scenarios.

关键词： energy efficiency resource allocation hybrid bursty services two-way multi-relay genetic algorithm

A new approach to test generation for combinational circuits

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Journal of Harbin Institute of Technology(New Series) 2009年第1期16卷 61-65页

作者：赵春晖侯艳丽胡佳伟兰海燕 school of information and communication engineering Harbin Engineering University

Aimed at the generation of high-quality test set in the shortest possible time, the test generation for combinational circuits （CC） based on the chaotic particle swarm optimization （CPSO） algorithm is presented according to the analysis of existent problems of CC test generation, and an appropriate CPSO algorithm model has been constructed. With the help of fault simulator, the test set of ISCAS＇ 85 benchmark CC is generated using the CPSO, and some techniques are introduced such as half-random generation, and simulation of undetected *** original test vector, and inverse test vector. Experimental results show that this algorithm can generate the same fault coverage and small-size test set in short time compared with other known similar methods, which proves that the proposed method is applicable and effective.

关键词： test generation combinational circuits: particle swarm ootimization: chaotic ontimization

Time and energy efficient data collection via UAV

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Science China(information Sciences) 2022年第8期65卷 182-196页

作者： Tianhao WANG Xiaowei PANG Jie TANG Nan ZHAO Xiuyin ZHANG Xianbin WANG school of information and communication engineering Dalian University of Technology Department of Electrical and Computer engineering Western University school of Electronic and information engineering South China University of Technology

Using unmanned aerial vehicles(UAVs) for data collection has emerged as a promising technique to achieve both time-and energy-efficient data gathering while keeping data fresh. In this study, two schemes are proposed for flight cycle minimization and energy efficiency maximization to collect data from ground sensors. We first minimize the flight cycle by jointly optimizing the wake-up scheduling of sensors, the trajectory,and the time slot, which is a mixed-integer non-convex problem and difficult to solve directly. To this end,we propose an iterative algorithm based on block coordinate descent and successive convex approximation to decouple the original non-convex problem into two sub-problems and the constraints are turned to be convex approximately. Furthermore, the energy efficiency is maximized since the limited energy is a critical issue in UAV communication systems. We approximate the two subproblems as convex optimizations by introducing slack variables and applying SCA. The approximate energy efficiency is a fractional expression, and we use Dinkelbach’s method to solve it. Numerical results show that the flight cycle is minimized in the first scheme with the data requirement satisfied, while in the second scheme, the energy efficiency is maximized with the trade-off between the transmission data and the propulsion power consumption.

关键词： data collection energy efficiency maximization time minimization trajectory optimization unmanned aerial vehicle (UAV)

Bitmap lattice index in road networks

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Journal of Central South University 2014年第10期21卷 3856-3863页

作者： Doohee Song Keun-Ho Lee Kwangjin Park information communication engineering Wonkwang University Division of information communication engineering Baekseok University

A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a server's workload increases as the query request increases when a server sends a client information. To solve this problem, we propose the BLI. The BLI denotes an object and a node as 0 and 1 in the Hilbert curve(HC) map. The BLI can identify the position of a node and an object through bit information; it can also reduce the broadcasting frequency of a server by reducing the size of the index, thereby decreasing the access latency and query processing times. Moreover, the BLI is highly effective for data filtering, as it can identify the positions of both an object and a node. In a road network, if filtering is done via the Euclidean distance, it may result in an error. To prevent this, we add another validation procedure. The experiment is conducted by applying the BLI to kNN query, and the technique is assessed by a performance evaluation experiment.

关键词： road network wireless broadcast spatial query bitmap lattice index(BLI)

Parallel lightpath provisioning under wavelength continuity constraint in multi-domain optical networks based on hierarchical path computation element

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Science China(information Sciences) 2013年第3期56卷 160-168页

作者： SUN Jian WANG ZongWei CHEN Zhen PENG YunFeng school of communication and information engineering University of Electronic Science and Technology of China school of Computer and communication engineering University of Science and Technology Beijing

Inter-domain path provision under a wavelength continuity constraint(WCC),including path computation and resource reservation procedures,is a major challenge in multi-domain wavelength division multiplexing(WDM) optical networks,because of the requirement for confidentiality between the *** on the hierarchical path computation element(PCE) architecture,this work proposed a path establishment scheme under a WCC to provide a fast inter-domain path establishment solution and decrease the influence of the *** hierarchical PCE architecture consists of a single parent PCE serving as the arbitrator and multiple child PCEs responsible for the child *** cooperation between the parent PCE and the child PCEs,both inter-domain path computation and inter-domain wavelength reservation can be processed in parallel to accelerate and optimize WCC lightpath provisioning and thus to reduce the blocking *** effectiveness of this solution has been evaluated through *** simulation results show that the proposed solution can achieve lower computation and reservation delays and thus lead to lower blocking probabilities on the multi-domain WCC paths.

关键词： multi-domain optical networks path computation resource reservation WCC hierarchical PCE

QE-integrating framework based on Github knowledge and SVM ranking

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Science China(information Sciences) 2019年第5期62卷 92-107页

作者： Qing HUANG Huaiguang WU school of Computer and information engineering Jiangxi Normal University school of Computer and communication engineering Zhengzhou University of Light Industry

The latest query expansion(QE) methods use the software development features for expanding queries. However, these methods allow only one feature to be considered at a time. To consider additional features simultaneously, we propose a QE method based on Github knowledge; this is a new comprehensive feature that covers both the existing features(i.e., the application program interface(API) information and crowd knowledge). It is extracted from the "pull requests" of code repositories on Github, which contain descriptions of a request and its commits, the participants’ comments and the API information of the changed files. In addition, we implement a black-box framework that integrates multiple QE methods based on the support vector machine ranking called Github knowledge search repository(GKSR). Our empirical evaluation shows that the GKSR outperforms the state-of-the-art QE methods CodeHow and QECK by 25%–32% in terms of precision.

关键词： code search query expansion Github knowledge SVM ranking crowd knowledge

HiQoS:An SDN-Based Multipath QoS Solution

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China communications 2015年第5期12卷 123-133页

作者： YAN Jinyao ZHANG Hailong SHUAI Qianjun LIU Bo GUO Xiao Computer and Network Center Communication University of China school of information engineering Communication University of China

Today's Internet architecture provides only "best effort" services,thus it cannot guarantee quality of service(QoS) for *** Defined Network(SDN)is a new approach to computer networking that separates control plane and forwarding planes,and has the advantage of centralized control and *** this paper,we propose HiQoS that provides QoS guarantees using ***,HiQoS makes use of multiple paths between source and destination and queuing mechanisms to guarantee QoS for different types of *** results show that our HiQoS scheme can reduce delay and increase throughput to guarantee *** importantly,HiQoS recovers from link failure very quickly by rerouting traffic from failed path to other available path.

关键词： SDN QoS multipath OpenFlow

Three-Dimensional Scattering of an Incident Plane Shear Horizontal Guided Wave by a Partly through-Thickness Hole in a Plate

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Chinese Physics Letters 2016年第1期33卷 75-79页

作者：朱文发张海燕徐建柴晓冬 school of communication and information engineering Shanghai University school of Urban Railway Transportation Shanghai University of Engineering Science

We investigate the three-dimensional （3D） scattering problem of an incident plane shear horizontal wave by a partly through-thickness hole in an isotropic plate, in which the Lamb wave modes are also included due to the mode conversions by the scattering obstacle in the 3D problem. An analytical model is presented such that the wave fields are expanded in all of propagating and evanescent SH modes and Lamb modes, and the scattered far-fields of three fundamental guided wave modes are analyzed numerically for different sizes of the holes and frequencies. The numerical results are verified by comparing with those obtained by using the approximate Poisson/Mindlin plate model for small hole radius and low frequency. It is also found that the scattering patterns are different from those of the SO wave incidence. Our work is useful for quantitative evaluation of the plate-like structure by ultrasonic guided waves.

关键词： of on mode is SH by Three-Dimensional Scattering of an Incident Plane Shear Horizontal Guided Wave by a Partly through-Thickness Hole in a Plate in