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Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards B3G

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 84-88页

作者： zhan Song-tao xu Guo-xin Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless mobile Ad-hoc network is a special network that all nodes can serf-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies （B3G or 4（3）. However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service （QoS）, which is strongly required by the beyond 3rd generation （B3G） system. In this article, the authors establish a scenario that contains B3G cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio （BER） to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.

关键词： Ad-hoc network B3G multipath routing energy consumption QoS

An improved genetic algorithm for searching for pollution sources

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Water Science and Engineering 2013年第4期6卷 392-401页

作者： Quan-min BU zhan-jun WANG Xing TONG School of Government Nanjing University Center for Social Risk and Public Crisis Management of Nanjing University Institute of Chemical Industry of Forest Products

As an optimization method that has experienced rapid development over the past 20 years, the genetic algorithm has been successfully applied in many fields, but it requires repeated searches based on the characteristics of high-speed computer calculation and conditions of the known relationship between the objective function and independent variables. There are several hundred generations of evolvement, but the functional relationship is unknown in pollution source searches. Therefore, the genetic algorithm cannot be used directly. Certain improvements need to be made based on the actual situation, so that the genetic algorithm can adapt to the actual conditions of environmental problems, and can be used in environmental monitoring and environmental quality assessment. Therefore, a series of methods are proposed for the improvement of the genetic algorithm：（1） the initial generation of individual groups should be artificially set and move from lightly polluted areas to heavily polluted areas; （2） intervention measures should be introduced in the competition between individuals; （3） guide individuals should be added; and （4） specific improvement programs should be put forward. Finally, the scientific rigor and rationality of the improved genetic algorithm are proven through an example.

关键词： genetic algorithm fitness selection crossover mutation pollution sources

The characterization of Γ-modules in terms of fuzzy soft Γ-submodules

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Applied Mathematics(A Journal of Chinese Universities) 2013年第2期28卷 217-239页

作者： ZHOU min XIANG Da-jing zhan Jian-ming College of Mathematics and Information Science Shaanxi Normal University Department of Mathematics Hubei University for Nationalities

In this paper,we focus on combining the theories of fuzzy soft sets with Γ-modules,and establishing a new framework for fuzzy soft Γ-*** main contributions of the paper are ***,we present the concepts of（R,S）-bi-Γ-submodules,quasi-Γ-submodules and regular Γ-***,some illustrative examples are given to show the rationality of the definitions introduced in this ***,several new kinds of generalized fuzzy soft Γ-submodules are proposed,and related properties and mutual relationships are also ***,we discover some intrinsic connections between the generalized fuzzy soft Γ-submodules presented in this paper and crisp Γ-submodules,and describe the relationships between regular Γ-modules and the generalized fuzzy soft Γ-submodules presented in this paper.

关键词： Fuzzy soft set Γ-module (∈ γ ∈ γ ∨ q δ)(resp. (■ γ ■ γ ∨ δ))-fuzzy soft left R-Γ-submodule(right R-Γ-submodules (R S)-bi-Γ-submodule quasi-Γ-submodule) regular Γ-module

Stability analysis in an AVQ model of Internet congestion control algorithm

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 22-28页

作者： zhan Zhen-qiu ZHU Jie xu Di Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China

This paper focuses on the local stability of a classical congestion control model in the Intemet, namely adaptive virtual queue （AVQ） algorithm with feedback delay. Firstly, necessary and sufficient stability conditions in terms of key tuning parameters are given, which can provide exact guidelines for setting system parameters. Furthermore, by computing the rightmost characteristic root, the optimal parameter configuration for AVQ is derived, which can guarantee superior stability performance. Finally, some simulation examples are given to illustrate the correctness of the theoretical analysis.

关键词： congestion control AVQ stability time delay system

Variational Image Restoration and Decomposition in Shearlet Smoothness Spaces

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Chinese Journal of Electronics 2017年第5期26卷 1017-1021页

作者： LI min xu Chen College of Mathematics and Statistics Shenzhen University College of Information Engineering Shenzhen University

We present the shearlet-based variational model for image restoration and *** new model can be seen as generalizations of DaubechiesTeschke’s *** using regularization term in shearlets smoothness spaces,and writing the problem in a shearlet framework,we obtain elegant shearlet shrinkage ***,the model allows us to incorporate general bounded linear blur operators into the *** experiments on denoising,deblurring and decomposition of images show that our algorithm is very efficient.

关键词： Shearlet Variaitional Decomposition Image restoration

Analysis of a conformal invisible device

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Frontiers of physics 2018年第2期13卷 67-75页

作者： Lin xu zhan Xiong Huan-Yang Chen Institute of Electromagnetics and Acoustics and Department of Electronic Science Xiamen University Xiamen 361005 China College of Physics Optoelectronies and Energy Soochow University Suzhou 215006 China

We perform a semi-analytical calculation of the field distributions of a conformal invisible device via mode expansions. For a discrete set of frequencies in the regime of wave optics, the conformal invisible device is perfectly transparent, which stems from the special conformal mapping and the refractive- index profile of the Mikaelian lens.

关键词： conformal transformation optics conformal invisible device refractive-index profile

Single cell tells the developmental story

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Science Bulletin 2016年第17期61卷 1355-1357页

作者： Zhengyan zhan Xin xu Yu V.Fu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of Sciences

Stem cells are undifferentiated cells that retain the ability to self-renew and differentiate into specialized cells,offering a promising resource to generate requisite cell types in regenerative medicine[1,2].Haematopoietic stem cells(HSCs)can differentiate into entire mature blood lineages,sitting at the apex of the haematopoietic hierachy and playing a key role in the long-term maintenance and stabilization of mammalian blood system functions[3,4].HSCs are mostly found in embryo and bone marrow,but also with small amounts in peripheral ***

关键词： maintenance differentiate specialized stabilization embryo mature story retain offering developmental

Subfemtosecond X-ray Pulses Produced Directly by High Harmonic Generation

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Chinese Physics Letters 2000年第7期17卷 491-492页

作者： WANG Ying-song xu Zhi-zhan Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

The generation of subfemtosecond pulses in hydrogen-like atoms through high-harmonic generation by using superintense multicycle driver pulses is numerically investigated. It is shown that a single subfemtosecond pulse can be directly generated when the driver pulse is strong enough to deplete the neutral atoms within several optical cycles. The propagation effect is neglected during the numerical examinations.

关键词： femtosecond pulse neglected

Potential Transmission Choice for Internet of Things(IoT):Wireless and Batteryless Communications and Open Problems

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China Communications 2021年第2期18卷 241-249页

作者： zhan xu Guanjie Hu minzheng Jia Lan Dong School of Information and Communication Engineering and with Key Laboratory of Modern Measurement&Control Technology Ministry of EducationBeijing Information Science&Technology UniversityChina Beijing Key Lab of Transportation Data Analysis and mining School of Computer and Information TechnologyBeijing Jiaotong UniversityBeijingChina Department of Information Engineering Beijing Polytechnic CollegeBeijingChina

The 5th generation mobile communications aims at connecting everything and future Internet of Things(IoT)will get everything smartly *** realize it,there exist many *** key challenge is the battery problem for small devices,such as sensors or *** backscatter,also referred to as or battery-free backscatter,is a new potential technology to address this *** early and typical type of batteryless backscatter is ambient ***,batteryless backscatter utilizes environmental wireless signals to enable battery-free devices to communicate with each *** devices first harvest energy from ambient wireless signals and then backscatter these signals so as to transmit their own *** paper reviews the current studies about batteryless backscatter,including various backscatter schemes and theoretical works,and then introduces open problems for future research.

关键词： batteryless backscatter battery-free channel state information(CSI) channel estimation multiple antennas signal detection symbiotic communication