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基于FPGA技术的通信原理课程实验教学研究

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陕西师范大学学报（自然科学版） 2007年第S2期35卷 201-203页

作者：姚展王明伟咸阳师范学院物理学系陕西科技大学电气与电子工程学院陕西咸阳712000

根据目前通信原理课程实验教学的现状,提出并利用FPGA及QuartusII软件设计通信原理课程实验系统,给出了实施方案.该系统结合了传统实验方法和计算机仿真技术的优点,在教学中效果明显提高.

关键词： FPGA QuartusII 通信原理实验

TREFFTZ DIRECT METHOD AND ITS RELATIVE PROBLEMS

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岩石力学与工程学报 2003年第1期22卷 115-121页

作者： Jin Wugen, Cheung Y K, Mao Xiaochun, Xue Xin( department of Mechanics and engineering Science, Fudan {2., Shanghai 2.0433 China) ( department of civil engineering, The {2. of Hong Kong, Hong Kong, China) department of Mechanics and engineering Science Fudan University 上海 200433 department of civil {2. The University of Hong Kong 香港

This paper attempts to further extend the so-called Trefftz direct method(TDM), which has been developed and applied to a wide variety of boundary value problems in recent years. In this approach, the complete system of solutions of the partial differential equations is used as weighting functions and a non-singular boundary integral equation is used as the starting formulation. Several relative problems are discussed here. They are the problems of necessary and sufficient conditions for Trefftz-type boundary integral equations: the relationship between the Trefftz method and the variational principle and the infrequently encountered but possible singular problems in the Trefftz method and the treatment in practice. Numerical results are presented to illustrate the computational efficiency of the approach and to demonstrate its advantages.

关键词： Trefftz直接法边界值数值解齐次差分方程

Condition Monitoring Method of the Equipment Based on Extension Neural Network

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Condition Monitoring Method of the Equipment Based on Extens...

2.10 Chinese Control and Decision Conference

作者： Juncai Zhang~1,Xu Qian~1,Yu Zhou~(1,2.,Ai Deng~3 1.School of Mechanical Electronic and Information engineering,China university of Mining and {2.(Beijing), Beijing,100083,China 2.department of Electrical & Computer engineering,university of Alberta,Edmonton,T6G 2.4,Canada 3.School of Software engineering,Tongji university,Shanghai,2.1804,China

In this paper,a novel condition monitoring method of equipment based on extension neural network(ENN) is ***,this paper introduces the central ideas of extension *** it presents the extension theory neural, including its structure and learning *** the end of the paper,the reduction gearbox of a certain equipment is researched and the extension neural network is employed to design a condition monitoring method that can detect the current condition of reduction *** experiment results indicate that the proposed method can determine the condition of machine rapidly and accurately with less time and computation.

关键词： Extension theory Extension neural network Condition monitoring Reduction gearbox

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锦屏大理岩卸荷本构模型与数值模拟研究

岩土力学 2012年第S2期33卷 401-407页

作者：李新平赵航肖桃李武汉理工大学道路桥梁与结构工程重点实验室武汉430070 武汉理工大学土木工程与建筑学院武汉430070 长江大学城市建设学院湖北荆州434023

锦屏二级水电站深埋引水隧洞位于高地应力区,对取自隧洞内的大理岩进行常规三轴压缩试验、峰前卸围压试验。基于大理岩的峰前卸荷试验,研究峰前卸荷条件下岩石的变形、参数及破裂特征,建立峰前卸荷条件下岩石的幂函数型Mohr强度准则,给... 详细信息

锦屏二级水电站深埋引水隧洞位于高地应力区,对取自隧洞内的大理岩进行常规三轴压缩试验、峰前卸围压试验。基于大理岩的峰前卸荷试验,研究峰前卸荷条件下岩石的变形、参数及破裂特征,建立峰前卸荷条件下岩石的幂函数型Mohr强度准则,给出数值仿真试验中大理岩的峰前卸载条件,利用有限差分程序FLAC3D建立了数值仿真模型,对模型进行了计算与分析,最后与室内试验结果对比,得到峰前卸荷状态下大理岩力学特性的相关规律。研究结果表明,幂函数型Mohr强度准则可较好地反映峰前卸荷条件下岩石的强度特性;卸围压初期,岩石试件呈现出明显的弹塑性特征;卸荷过程中岩石试件发生破坏时的峰值强度和围压降值随着围压增加而变大。研究结论揭示了锦屏大理岩卸载应力路径下的力学特性,具有一定的理论参考价值。

关键词：大理岩峰前卸荷强度准则数值仿真

Weighted ENN difference schemes

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Communications in Nonlinear Science and Numerical Simulation 1996年第3期1卷 46-49页

作者： Ruquan WANG Yiqing SHEN(Institute of Computational Mathematics and Scientific/engineering Computing,Academia Sinica)(department of Mathematics, Yunnan {2.)E-mail: wrq@*** [b] Institute of Computational Mathematics and Scientific/engineering Computing Academia Sinica USA [a] department of Mathematics Yunnan university USA

In our previous paper[1] two weighted NND dtherence schemes were presentedby using proper weighted functions instead of minmod functions. As a result,the WNNDschemes enhance accuracy and yield smoother numrical auxes. In this paper two weightedENN schemes based on the ENN scheme[2. are constructed. The ENN scheme and WENNschemes are uniformly second-order accuracy and can achieve third-order accuracy in certainsmooth regions

关键词： ENN Weighted ENN difference schemes

Study of Shipboard Power System Service Restoration

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Study of Shipboard Power System Service Restoration

Particulate problems of different occupational environments in Hong Kong

2.04安全科学与技术国际会议

作者： YANG Xiuxia1 ZHANG Xiaofeng1 ZHANG Yi2.& Zhen Hongbin1 (1 department of Electrical engineering Naval {2. of engineering Wuhan 430033 Hubei China) (2.department of Automatic Control Naval Aeronautical engineering Academy Yantai 2.4001 Shandong China)

The shipboard power system(SPS) supply energy to sophisticated systems for weapons , communications, navigation and operation, so when the system is damaged, the faults should be isolated and restored

关键词： shipboard power system service restoration enlarge matrix fault handle genetic algorithm

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Journal of Environmental Sciences 1999年第4期11卷 385-391页

作者： LEUNG Y.C., CHEUNG K.K. (department of Mechanical engineering, The {2. of Hong Kong, Hong Kong Special Administrative Region) 香港大学机械工程系香港

This paper studied the air pollution problems that occurred in various working environments in Hong Kong through questionnaire survey and field measurements. Results of the survey showed that more than half of the respondents, who were affected by different kinds of air pollution, were suffering from either eye and nasal allergies, or throat irritation. Many of them recognized dust particulate to be the most serious air pollutant in their working environments. A portable laser dust monitor was employed to measure the levels of dust particulate that would be inhaled by people of different occupations and subject to different environments. The measurement results revealed that only some occupations were exposed to unacceptably high particulate levels. Generally, the particulate levels of most of the studied working environments, catering premises and entertainment places were much lower than the ambient levels and unlikely to pose any occupational hygiene problems.

关键词： air pollution dust particulate Hong Kong

Calculation of the turbulent two-phase flow in direct-injection diesel engine

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Calculation of the turbulent two-phase flow in direct-inject...

Rainfall-induced landslide stability analysis in response to transient pore pressure——A case study of natural terrain landslide in Hong Kong

第五届国际非线性力学会议

作者： Yong-feng Liu~(1,2.,You-tong Zhang~(1*),Hong-seng Tian~2.Jian-jun Qin~3 (1.School of Mechanical and Vehicular engineering,Beijing Institute of technology,Beijing 100081,China 2.School of Mechanical-Electronic and Automobile engineering,Beijing Institute of civil engineering and Architecture,Beijing 100044,China 3.School of Mechanical,Electronic and Control engineering,Beijing Jiaotong university, Beijing 100044,China)

＜正＞To calculate the governing equations for the turbulent two-phase flow the CFD code（KIVA-3V） was changed to fit for the gas phase and the liquid *** the gas phase,the Favre-averaging is used for the continuity equation and momentum *** a result of the averaging,unclosed terms appear which require *** order to make the turbulent Reynolds stress tensor closed in the momentum equation,the so-called Boussinesque-approximation, which is based on an analogy between molecular diffusion and diffusion turbulent eddies,was *** equations for turbulent kinetic energy k and turbulent dissipation e were added to close the Navier-Stokes *** temporal differencing scheme in KIVA-3V is largely *** the Lagragian phase,implicit differencing was used for all diffusion terms and terms associated with pressure wave propagation.A method similar to the SIMPLE-algorithm was used to solve the coupled implicit set of *** the liquid phase,the probability density function（PDF） method was used for solving the droplet spray *** Taylor analogy breakup（TAB） model used in the standard KIVA-code was extended with a deformation velocity such that their lifetime was extended to match experimentally observed jet breakup ***,other models such as the Rayleigh-Taylor（R-T） model,discrete droplet models（DDM） *** ***, cylinder pressure and corresponding heat release rates in a directed-injection diesel engine were calculated and compared with the *** gives the theory and method about calculating turbulence exactly in directed-injection diesel engines.

关键词：

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Science China(Technological Sciences) 2003年第z1期46卷 52-68页

作者： LAN Hengxing, ZHOU Chenghu C. F. LeeWANG Sijing & WU Faquan State Key Laboratory of Natural Resources and Environmental System, Institute of Geographical Sci-ences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China department of civil {2., Hong Kong university, Hong Kong, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China Chinese Acad Sci State Key Lab Nat Resources & Environm Syst Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Univ Hong Kong Dept Civil Engn Hong Kong Hong Kong Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.

关键词： rainfall-induced landslide, transient pore pressure, landslide stability in response to rainfall, GIS.