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Analysis and Simulation for Capacity of Time Division-Synchronous Code Division Multiple Access System

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Journal of Systems engineering and Electronics 2002年第4期13卷 91-97页

作者： Sun Chengjun, Zhang Zhongzhao, Ba Yong2 & Cao Pengzhi (Communication Research ("enter, harbin Institute of Technology, harbin 150001, P. R. china department of Electronic engineering, Tsinghua university, Beijing 100084, P. R. china Research and Development Division, Shanghai Bell Company Limited, Shanghai 200092, P. R. china) Communication Research Center Harbin Institute of Technology Harbin 150001 P. R. China department ot Electronic engineering Isinghua University Beijing 100084 P. R. China Research and Development Division Shanghai Bell Company Lirmted Shanghai 200092 P. R. China

Capcity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access) system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interference in uplink and the mean of sum of power allocation in downlink are given, by which uplink and downlink capacity is analyzed. Furthermore, we give the simulation models for both uplink and downlink capacity. The results from theoretical analysis and simulation fit very well. In the end, the maximum number of users that TD-SCDMA system can serve for 12.2 k speech service is given.

关键词： Code division multiple access Probability Resource allocation Simulation Time division multiple access

LINEAR ACTIVE STRUCTURES AND MODES (Ⅱ) —DISCRETE SYSTEMS AND BEAMS

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Applied Mathematics and Mechanics(English Edition) 2004年第8期25卷 854-862页

作者：王永刚龚靖School of Civil engineering and Mechanics Xi'an Jiaotong university Xi'an 710049 P.R.china department of Civil engineering northeast china Institute of Electric Power Jilin 132012 P.R.china 张景绘School of Civil engineering and Mechanics Xi'an Jiaotong university Xi'an 710049 P.R.china School of Civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.ChinaSchool of Science Chang'an University Xi'an 710064 P.R.China

The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active beams were discussed, especially, the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-storeyed building with sensors and actuators. The concept of the adjoint active structure was extended from the discrete systems to the beams that were the representations of the continuous structures. Two types of beams with different placements of the measuring and actuating systems were discussed in detail. One is the beam with the discrete sensors and actuators, and the other is the beam with distributed sensor and actuator function. The orthogonality conditions were derived with the modal shapes of the active beam and its adjoint active beam. An example shows that the variation of eigenvalues with feedback amplitude for the homo-configuration and non-homo-configuration active structures.

关键词： I) ". The characteristics of the active discrete systems and active beams were discussed especially the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-s

Performance prediction and flow analysis in the vaned distributor of a pump turbine under low flow rate in pump mode

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中国科学：技术科学英文版 2010年第12期53卷 3302-3309页

作者： YIN JunLian1, LIU JinTao1, WANG LeQin1, JIAO Lei1, WU DaZhuan1 & QIN DaQing2 1 Institute of Chemical Machinery, department of Chemical and Biological engineering, Zhejiang university, Hangzhou 310027, china 2 harbin Institute of Large Electrical Machinery, harbin 150001, china 1. Institute of Chemical Machinery Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China2. Harbin Institute of Large Electrical Machinery Harbin 150001 China

The main goal of this work is to investigate the possible different flow patterns existing in pump turbine under off-design conditions in pump mode. Numerical simulations by solving the Navier-Stokes equation, coupled with the "SST k-ω" turbulence model, were carried out. Flow characteristics were assumed to be stalled in the appropriate region of ?ow rate levels of Q/QD=0.15–0.61. The simulation result was compared with experimental data and they showed good agreement. Consequently, velocity fields in three axial locations in stay vanes and guide vanes were analysed in details. It was shown that "jet-wake" flow pattern exists near the band, which changes little in the whole shape with flow rate increasing; to the middle location of vanes, reverse flow begins to appear on the interface between the runner and guide vanes, which will disappear gradually as the flow rate increases; massive reverse flow is captured near the crown, whose intensity will be weakened as the flow rate increases. Ultimately, it was found that the special head-flow profile can be ascribed to the special hydraulic loss characteristics of the stay vanes and guide vanes.

关键词： pump turbine flow simulation stalled flow guide vane

Relations Between Characteristic Function,Positive P-Representation and Coherent Thermal State

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Communications in Theoretical Physics 2007年第7期48卷 67-70页

作者： FAN Hong-Yi XU Xing-Lei department of Material Science and engineering,university of Science and Technology of china,Hefei 230026,china2 department of Physics,Shanghai Jiao Tong university,Shanghai 200030,china3.department of Physics,Heze university,Heze 274015,china department of Material Science and engineering University of Science and Technology of China department of Physics Shanghai Jiao Tong University department of Physics Heze University

We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light ***,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained.

关键词： coherent thermal state characteristic function positive P-representation

Infinite-dimensional Hamiltonian Lie superalgebras

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Science china Mathematics 2010年第6期53卷 1625-1634页

作者： MU Qiang1,2 & ZHANG YongZheng1,1School of Mathematics and Statistics,northeast Normal university,Changchun 130024,china 2School of Mathematics,harbin Normal university,harbin 150025,china 1. School of Mathematics and Statistics Northeast Normal University Changchun 130024 China2. School of Mathematics Harbin Normal University Harbin 150025 China

The natural filtration of the infinite-dimensional Hamiltonian Lie superalgebra over a field of positive characteristic is proved to be invariant under automorphisms by characterizing ad-nilpotent *** are thereby able to obtain an intrinsic characterization of the Hamiltonian Lie superalgebra and establish a property of the automorphisms of the Lie superalgebra.

关键词： Hamiltonian superalgebra filtration automorphism

Effect of rare earths on phase transformation in as-cast ZA27 alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedPhysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalScience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 27 alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 27-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 27-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 27-RE alloy were finer than in ZA 27 alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 27-RE alloy was higher than that of ZA 27 alloy.

关键词： microstructure change compressive creep rare earths ZA 27 alloy

Parameter identification theory of a complex model based on global optimization method

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3 1 College of Automotive engineering, South china university of Technology, Guangzhou 510640, china 2 Beijing Research Institute of Mechanical and Electrical Technology, Beijing 100083, china 3.department of engineering Mechanics, Tsinghua university, Beijing 100084, china 1. College of Automotive engineering South China University of Technology Guangzhou 510640 China 2. Beijing Research Institute of Mechanical and Electrical Technology Beijing 100083 China 3. department of engineering Mechanics Tsinghua University Beijing 100084 China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

A MESSAGE-DRIVING FORMALISM FOR MODELING AND SIMULATION OF MULTI-AGENT SUPPLY CHAIN SYSTEMS

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Journal of Systems Science and Systems engineering 2011年第4期20卷 385-399页

作者： Wenzhe TAN1 Yueting CHAI2 Yi LIU3 1department of Automation, Tsinghua university, Beijing, 100084, china 2department of Automation, Tsinghua university, Beijing, 100084, china 3department of Automation, Tsinghua university, Beijing, 100084, china department of Automation Tsinghua University Beijing China

To acquire a competitive advantage in the expanding market, manufacturing enterprises should be able to manage their supply chains as effectively as possible. It is now becoming popular to model supply chains as multi-agent systems and use discrete event simulation to learn more about their behaviors or investigate the implications of alternative configurations. In order to enhance the computational efficiency and keep the simulation credibility, this paper proposes a message-driving formalism for the simulation of multi-agent supply chain systems. Through the message-driving formalism, the problem of shared variables is addressed and the parallel operation of agents is implemented. Simulation experiments with a prototype implementation show that the message-driving formalism is able to provide credible results in significantly less simulation time.

关键词： Supply chain multi-agent system modeling and simulation parallel discrete event simulation message-driving formalism

“有效降低全社会物流成本”研讨会专家观点综述

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中国流通经济 2024年第5期38卷 3-17页

作者：本刊编辑部《中国流通经济》编辑部

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处... 详细信息

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处联合主办了“有效降低全社会物流成本”研讨会。本次研讨会邀请我国流通物流领域的专家学者,围绕物流服务实体经济和人民群众、物流成本构成、交通运输体系改革、统一高效物流市场构建和现代商贸流通体系完善等问题,发表观点,为探索有效降低全社会物流成本可行路径,构建现代流通体系提供理论支持和实践指导。本刊编辑部对专家阐述的主要观点进行了归纳整理,以飨读者。

关键词：全社会社会物流成本新质生产力流通体系降本增效