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Chinese Journal of Electronics 2016年第4期25卷 686-691页

作者： zhan xin zhanG Rong Department of Electronic Engineering and Information Science University of Science and Technology of China Key Laboratory of Electromagnetic Space Information Chinese Academy of Sciences

In this paper,an Entropy-constrained dictionary learning algorithm(ECDLA) is introduced for efficient compression of Synthetic aperture radar(SAR) complex *** RI encodes the Real and imaginary parts of the images using ECDLA and sparse representation,and ECDLA AP encodes the Amplitude and phase parts *** compared with the compression method based on the traditional Dictionary learning algorithm(DLA),ECDLA RI improves the Signal-to-noise ratio(SNR) up to 0.66 dB and reduces the Mean phase error(MPE) up to 0.0735 than DLA *** the same MPE,ECDLA AP outperforms DLA AP by up to 0.87 dB in ***,the proposed method is also suitable for real-time applications.

关键词： Synthetic aperture radar image compression Dictionary learning Sparse representation

Research of stochastic weight strategy for extended particle swarm optimizer

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 122-124,134页

作者： XU Jun-jie YUE xin xin zhan-hong Economics and Management College Anqing Teachers CollegeAnqing 246133 China School of Economics and Management Beijing University of Posts andTelecommunications Beijing 100876 China

To improve the performance of extended particle swarm optimizer, a novel means of stochastic weight deployment is proposed for the iterative equation of velocity updation. In this scheme, one of the weights is specified to a random number within the range of [0, 1] and the other two remain constant configurations. The simulations show that this weight strategy outperforms the previous deterministic approach with respect to success rate and convergence speed. The experiments also reveal that if the weight for global best neighbor is specified to a stochastic number, extended particle swarm optimizer achieves high and robust performance on the given multi-modal function.

关键词： particle swarm optimization evolutionary computation,stochastic weight function optimization

Study on the share ratio between a service provider and two carriers

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 120-124页

作者： YUE xin XU Jun-jie xin zhan-hong School of Economics and Management Beijing University of Posts and Telecommunications Bcijing 100876 China

Based on the premise of obtaining optimal revenue, a mathematical model about operation strategies of service provider （SP） in duopoly telecom market was established in this article. In consideration of complexities, the model was transformed from a tri-game to two-party game model under four hypotheses. Nash equilibrium solution between SP and two carriers was proposed with detailed analyses. The value ranges under different cases provided a reference for carriers and SP while deciding share ratios.

关键词： duopoly marketk Nash equilibrium tri-game win-win game

A new eremophilane-type sesquiterpene from Ligularia virgaurea

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Chinese Chemical Letters 2009年第8期20卷 949-951页

作者： Dong Qing Fei zhan xin zhang School of Pharmacy Lanzhou University Lanzhou 730000 China

A new eremophilane-type sesquiterpene, 1α,8β,10β-trihydroxy-6β-（2-methylacryloy1）0xyeremophil-7（11）-en-8a,12-oide,was isolated from the roots of Ligularia virgaurea. Its structure was established on the basis of various spectroscopic analyses, including the 1D, 2D NMR techniques and HR-ESI-MS.？ 2009 zhan xin zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ligularia virgaurea Compositae Eremophilane Sesquiterpene

Numerical study of thermal characteristics of double skin facade system with middle shade

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Frontiers in Energy 2021年第1期15卷 222-234页

作者： Shaoning LIU Xiangfei KONG Hua YANG Minchao FAN xin zhan School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China

Architectural shade is an effective method for improving building energy efficiency.A new shade combined with the double skin façade(DSF)system,called middle shade(MS),was introduced and developed for *** this paper,a 3D dynamic simulation was conducted to analyze the influence of MS combined with DSF on the indoor thermal *** research on MS for DSF involves the temperature,the ventilation rate,the velocity distribution of the air flow duct,and the indoor *** results show that the angle and position of the shade in the three seasons are different,and different conditions effectively enhance the indoor thermal *** summer,the appearance of MS in DSF makes the indoor temperature significantly *** indoor temperature is obviously lower than that of the air flow duct,and the temperature of the air flow duct is less affected by *** influence of the position of blinds on indoor temperature and ventilation rate is greater than the influence of the angle of *** to the climate characteristics of winter and transition season,in winter,early spring,and late autumn,the indoor temperature decreases with the increase of the position of blinds at daytime,but the opposite is true at *** results found in this paper can provide reference for the design and use of MS combined with DSF in hot summer and cold winter zone.

关键词： middle shade position thermal characteristics double skin facade

An architecture of knowledge management system based on agent and ontology

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 126-130页

作者： FU Rui-xue YUE xin SONG Ming xin zhan-hong School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876 China

To solve the problems in knowledge management system （KMS）, such as information sharing, the ability to extend and re-engineer, and the reusable ability of legacy systems in distributed and heterogeneous environments. This article presents a method based on agent and ontology of designing KMS. This method consists of two agencies. One is knowledge agency with three agents supporting knowledge management process. The other is application agency with three agents supporting knowledge application. In this method, ontology is used to represent the knowledge in knowledge base and the content in the message exchanged among agents. To demonstrate the advantages of this method, experiments have been carried out and the results imply that this method is efficient and effective for small and medium-size enterprises to design KMS.

关键词： KMS multi-agent system (MAS) ontology

The Design and Implementation of Embedded Security CPU Based on Multi-strategy

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Chinese Journal of Electronics 2016年第5期25卷 801-806页

作者： LI Dongfang zhan xin TONG Qiaoling ZOU Xuecheng LIU Zhenglin School of Optical and Electronic Information Huazhong University of Science and Technology Beijing Institute of Computer Technology and Application Department of Electrical and Computer Engineering Texas A&M University

Control flow monitoring, information flow tracking and memory monitoring are the three main solutions to enhance the security of embedded system at the hardware architecture level. However, most of the current studies about the security of embedded system consider the above solutions in separate dimensions rather than a combined effort. We start from the operation model at the instruction level, and propose a security multi-strategy which combines information flow tracking and memory monitoring by studying the security operating mechanism of embedded system. As a hardware approach this strategy extends the embedded processor architecture with additional security defense control. The experimental results show this multi-strategy is more effective and can detect more malicious attacks than a single solution. The effectiveness of our proposed security multi-strategy has been verified in a Field programmable gate array(FPGA) prototype platform based on a customized Leon3 microprocessor.

关键词： Information flow security Taint tracking Memory monitor module Embedded processor architecture

Exact mesh shape design of large cable-network antenna reflectors with flexible ring truss supports

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Acta Mechanica Sinica 2014年第2期30卷 198-205页

作者： Wang Liu Dong-Xu Li xin-zhan Yu Jian-Ping Jiang College of Aerospace Science and Engineering National University of Defense Technology Academy of Space Information System Academy of Space Electronic Information Technology

An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the generation of exact spatial parabolic mesh configurations of such reflector was proposed. By incorporating the traditional force density method with the standard finite element method, this proposed approach had taken the deformation effects of flexible ring truss supports into consideration, and searched for the desired mesh shapes that can satisfy the requirement that all the free nodes are exactly located on the objective paraboloid. Compared with the conventional design method,a remarkable improvement of surface accuracy in the obtained mesh shapes had been demonstrated by numerical examples. The present work would provide a helpful technical reference for the mesh shape design of such cable-network antenna reflector in engineering practice.

关键词： Cable-network Mesh shape design Support deformation Force density Surface accuracy

A New Taraxastane-type Triterpenoid from Potentilla multicaulis

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Chinese Chemical Letters 2006年第12期17卷 1573-1575页

作者： Ping Lin LI zhan xin zhanG Zhong Jian JIA State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

A new taraxastane-20β, 28β-epoxy-28-hydroxy-3β, 11 α-diol- 11-p-hydroxylbenzoate was isolated from the roots of Potentilla multicaulis. Its structure was elucidated by spectroscopic methods, especially 2D NMR tech... 详细信息

关键词： Potentilla multicaulis Rosaceae taraxastane-type triterpenoid.

Synthesis of mechanically robust porous carbon monoliths for CO2 adsorption and separation

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Journal of Energy Chemistry 2020年第3期29卷 56-61页

作者： Jie Du Wen-Cui Li zhan-xin Ren Li-Ping Guo An-Hui Lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Porous carbon materials with developed porosity,high surface area and good thermal-and chemicalresistance are advantageous for gas adsorption and ***,most carbon adsorbents are in powder form which exhibit high pressure drop when deployed in practical separation *** monolithic carbons have largely addressed the pulverization problem and preserved kinetics and usually suffer from abrasion during multiple adsorption-desorption ***,we proposed the designed synthesis of mechanically robust carbon monoliths with hierarchical pores,solid nitrogen-containing *** synthesis started with the polymerization of resorcinol and formaldehyde under weakly acidic conditions generated from cyanuric acid,and then an appropriate amount of hexamethylenetetramine(HMTA)was added as a crosslinker to prompt the formation of three dimensional *** carbonization process,the as-obtained porous carbon monoliths have a high radial compressive strength of 886 N/cm as well as a BET specific surface area of up to 683 m2/*** approximately 1 bar,the CO2 equilibrium capacities of the monoliths are in the range of 3.1–4.0 mmol/g at 273 K and of 2.3–3.0 mmol/g at 298 K,exhibiting high selectivity for the capture of CO2 over N2 from a stream which consists of 16.7%(v%)CO2 in ***,they undergo a facile CO2 release in an argon stream at 298 K,indicating a good regeneration *** cycle testing,sieving and regeneration,the adsorbent has no mass loss,compared to that of its fresh counterpart.

关键词： Carbon monoliths High mechanical strength Adsorption Gas separation