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861.
Wang FuhengBeijing Institute of Environment Features P.O.Box - Beijing China 《系统工程与电子技术(英文版)》1991,(1)
A systematic elaboration is given on atomic and molecular theory problems encountered in dealing with space science and engineering. Three sections are presented in the paper on calculations for gas thermodynamic and transfer properties, characteristics of the optical radiation from the reentry' bodies, and the interaction between surfaces of man-made satellites and incident particles. Researches on them are much related to the fundamental problems regarding the atomic and molecular theory. 相似文献
862.
本文描述了澳大利亚肺鱼N.forsteri幼体及成体头部侧线及陷器的分布、走向、与外界相通的开孔数目以及它们从幼体到成体的变化,与前人研究作了比较。本文还首次报道了这一动物皮肤中电接受器官的分布及电镜结构以及与非洲肺鱼的不同。 相似文献
863.
YE Minqiang 《系统科学与系统工程学报(英文版)》1994,(2)
ADynamicModelofSensibilityAnalysisinProjectEvaluationYEMinqiang(Dept.ofI.B.M.,HuaqiaoUniversity,Quanzhou,Fujian362011,China)A... 相似文献
864.
K.H.DTZ 《复旦学报(自然科学版)》2007,(5)
1 Results The lecture will address aspects of functional organometallics related to the development of novel organometallic materials.In chromium complexes of fused arenes-regio-and diastereoselectively accessible by chromium-templated benzannulation of arylcarbenes by alkynes[1]-a haptotropic migration of the chromium fragment along the π-face of fused arenes is controlled by both thermodynamics and the substitution pattern of the arene and the metal coligand sphere,and can be applied towards an organometallic switch[2].See Fig.1. 相似文献
865.
Sun Jitao & Zhang Yinping Dept. of Application Mathematics Tongji University Shanghai P.R.China Liu Yongqing & Deng Feiqi Dept. of Automation South China University of Technology Guangzhou P.R.China 《系统工程与电子技术(英文版)》2002,13(1)
1 .INTRODUCTIONThestabilityoftheintervalmatrixanduncertainsystemwithtimedelayhasbeenaconsideredbyresearchersinreferences [1~ 1 3 ].Thestabilityofthefollowingintervaldynamicalsystemwithsingletimedelay x(t) =N[P ,Q]x(t) +N[C ,D]x(t-τ)hasbeenconsideredinpreviousreferen… 相似文献
866.
Lu Caicheng & Wang BaofaDept. of Electronic Eng. Beijing University of Aeronautics Astronautics Beijing China 《系统工程与电子技术(英文版)》1991,(2)
A new method of calculating the radai cross section (RCS) for wing-body blended targets is presented and verified. The method utilizes a computer program for modeling targets' geometry in terms of small pieces. The calculation is based on physical optics approximation. Examples are given to show the validity of the method. 相似文献
867.
868.
很少有像航空工业那样更能引起公众注意的.因而,当阿洛哈公司的243次航班在被掀去机身上部18英尺的一块外壳,于1988年4月28日在毛伊迪卡哈卢机场紧急迫降时,全世界为之一震.当这架已飞行了19年的波音737飞机以每小时330哩的速度飞行在2万4千英尺的高空时,突然猛烈地在客舱上方掀开一块.由于机舱内急剧的减压,使得一名空中小姐被抛出机外,并有61名乘客受伤. 相似文献
869.
Li Layuan & Li Chunlin Department of Computer Science Wuhan University of Technology Wuhan P. R. China 《系统工程与电子技术(英文版)》2002,13(4)
In recent years, QoS multicast routing has continued to be a very important research topic in the areas of networks. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithm deals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overhead for constructing a multicast tree, the proof for correctness of the HAQMR is given, and the performance of the HAQMR is evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing. 相似文献
870.
PERSPECTIVES ON URBAN WATER INFRASTRUCTURE IN CHINA FOR THE 21~(ST) CENTURY: SDMUWEIC MODEL 总被引:2,自引:0,他引:2
Junying CHU Jining CHEN Ji ZOUDepartment of Environmental Science EngineeringTsinghua University Beijing P.R. ChinaDepartment of Environmental Economics ManagementRenmin University of China Beijing P.R. China 《系统科学与系统工程学报(英文版)》2003,12(4)
Based on system dynamics approach, SDMUWEIC model is developed in order to evaluate future dynamics of urban water infrastructure development in China. Firstly, this paper presents the basic structure and characteristics of the model, focusing on water infrastructure's dynamic relationships with population increase, economic development, water resources shortage and water conservation practices. Secondly, model veracity and robustness tests based on behavior reproduction and uncertainty analyses are illustrated. Thirdly, based on the model, future patterns of China's urban water infrastructure investment requirements are simulated, and effectiveness of two different policy scenarios are evaluated. Finally, conclusions and policy implications are drawn, allowing insights into China's sustainable water infrastructure policies and managements. 相似文献