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Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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Science China(Technological Sciences) 2005年第z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2.& WANG Jianguo31. institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100060, China 3. Tropical Marine Science institute, National University of{2., 10 Kent Ridge Crescent,{2. 1192.0 Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ singapore Trop Marine Sci Inst Singapore 119260 Singapore

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3) the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 30% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

An Integration Framework for Digital Progressive Die Design and Manufacturing

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武汉理工大学学报 2006年第S1期28卷 55-61页

作者： A. Y. C. Nee Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260

This paper reports an effort to develop an intelligent integration framework for digital progressive die design and manufacturing. Both data-and process-centric integration functions are provided by the framework as if a special ight-weight PDM/PLM (Product Data Management/Product Lifecycle Management) and WM (Workflow Management) system is embedded in the integrated engineering environment. A flexible integration approach based on the CAD (Computer-Aided Design) framework tenet is employed to rapidly build up the system while the intrinsic characteristics of the process are comprehensively taken into account. Introduction of this integration framework would greatly improve the dynamic performance of the overall progressive die design and manufacturing process.

关键词： progressive die digital manufacturing product data integration process integration integration frame

Study on optimization of agent initial positions in land combat simulation

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Progress in Natural Science:Materials International 2004年第3期 65-69页

作者： WU Chunguo 1,2. , LIANG Yanchun* 1, 2. , LEE Heow Pueh 2. LU Chun 2.and YANG Xiaowei 3,4 (1. College of Computer Science and Technology, Key Laboratory of Symbol Computation and Knowledge Engineering of the Ministry of Education, Jilin University, Changchun 130012. China 2. institute of high performance computing, singapore 11752.,{2. 3. Department of Applied Mathematics, South China University of Technology, Guangzhou 510640, China 4. Centre for ACES, Department of Mechanical Engineering, National University of{2., 1192.0,{2.) CollegeofComputerScienceandTechnology KeyLaboratoryofSymbolComputationandKnowledgeEngineeringoftheMinistryofEducationJilinUniversityChangchun130012China Institiuteofhighperformance{2. Singapore117528Singapore DepartmentofAppliedMathematics SouthChinaUniversityofTechnologyGuangzhou510640China

The use of computational intelligence based techniques in the optimization of agent initial positions in land combat simulations is studied. A novel method for the reduction of support vectors in the support vector machine (SVM) is presented. The optimization on the width of the Gaussian kernel function and the combination of the SVM with the radial basis function neural network are performed in the proposed method. Simulation results show that the proposed method can improve the running efficiency drastically compared with that using the traditional SVM with the same precision. We also summarize and present some experiences and trends in the study on the optimization problem in land combat simulation.

关键词： multi agent support vector machine radial basis function genetic algorithm regression.

吉林省2.2.年初中毕业学业水平考试评价与分析报告

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吉林省教育学院学报 2024年第4期 1-23页

作者： Junior high School Teaching Research and Training Department,Jilin Provincial institute of Education 吉林省教育学院初中教研培训部

学科：数学成员：徐明国，贾长彬，梁凯毓吉林省初中毕业学业水平考试数学试卷具有时效性、稳定性和创新性。2.2.年初中毕业学业水平考试数学试卷持续贯彻新课程标准的理念，考查内容以第四学段数学学科核心知识为主，素材选取以人民教...

学科：数学成员：徐明国，贾长彬，梁凯毓吉林省初中毕业学业水平考试数学试卷具有时效性、稳定性和创新性。2.2.年初中毕业学业水平考试数学试卷持续贯彻新课程标准的理念，考查内容以第四学段数学学科核心知识为主，素材选取以人民教育出版社的教材为主，其他版本的教材为辅。试卷整体结构合理，试题以原创为主，难易适中，稳中有变。

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来源：博看期刊

China's Economy in 2.07/2.08:Coping with Problems of Runaway Growth

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China & World Economy 2008年第2期16卷 1-18页

作者： John Wong East Asian institute National University of SingaporeSingaporeSingapore

Fuelled by high domestic investment and rapid export expansion, China ＂s economy grew by ll.4 pereent in 2.07, the highest increase since 1994 and the fifth eonseeutive year of double-digit growth. Such spectacular growth {2. is unprecedented in the world＇s economic history. However, the Chinese Government is again worried about a possible ＂hard landing＂for the economy, as no economy can sustain very strong growth for extremely long period without overheating. Cracks in China ＂s economy are indeed emerging. The eonsumer priee index shot up to 6.9percent in November 2.07, the highest level in a decade, with the annual inflation for 2.07 rising to 4.S pereent, well above the government＇s ＂comfort level＂ of 3 percent. This prompted China＇s top leadership to declare that reducing economic overheating and curbing inflation would be the top poliey priorities for 2.08. To contain such cost-push inflation, the government has to tackle its root causes, such as excessive liquidity, which is caused by the undervaluation of the renminbi, which in turn is attributable to China＇s chronic external and internal maeroeeonomie imbalances~ high growth is likely to continue in 2.08, at around l O pereent, with inflation of S-6 pereent expected, despite the anticipated tighter maeroeeonomie control measures and the more troubled external economic environment （e.g. the expected US economic slowdown）. Regardless, China ＂s fundamental problems associated with runaway growth will largely remain. In addition, if the US economy slips into a serious recession, the Chinese economy will not be able to deeouple from it and escape unscathed.

关键词： high growth domestic demand overheating inflation recession

Estimate of error bounds in the improved support vector regression

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Progress in Natural Science:Materials International 2004年第4期 76-78页

作者： SUN Yanfeng, LIANG Yanchun, WU Chunguo, YANG Xiaowei, LEE Heow Pueh2.and LIN Wu Zhong (1. College of Computer Science and Technology, Jilin University, Changchun 130012. China 2. institute of high performance computing, singapore 11752.,{2. 3. Department of Applied Mathematics, South China University of Technology, Guangzhou 510640, China 4. Centre for ACES, Department of Mechanical Engineering, National University of{2., 1192.0,{2.) College of Computer Science and Technology Jilin UniversityChangchun 130012China College of Computer Science and Technology Jilin UniversityChangchun 130012China institute of high {2. computing Singapore 117528Singapore Department of Applied Mathematics South China University of TechnologyGuangzhou 510640China Centre for ACES Department of Mechanical EngineeringNational University of Singapore119260Singapore institute of high {2. computing Singapore 117528Singapore

An estimate of a generalization error bound of the improved support vector regression (SVR) is provided based on our previous work. The boundedness of the error of the improved SVR is proved when the algorithm is appl... 详细信息

关键词： support vector regression (SVR) generalization error approximation error estimation error.

A CONDENSED REVIEW ON THE FABRICATION OF HOLLOW FIBER MEMBRANES FOR GAS SEPARATION:HISTORICAL DEVELOPMENT AND TECHNOLOGY CHALLENGES AHEAD

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化工学报 2000年第S1期51卷 1-4页

作者： Chung Tai-Shung (institute of Materials Research & Engineering 3 Research Link, singapore, 117602.

A review on the polymeric hollow fibers membranes for gas separation has been conducted. In order to deyelop high performance membranes for gas separation, there are a few technology challenges awaiting the chemical engineers to overcome. There are four major challenges, namely: 1) material selection and synthesis; 2. fabrication of hollow fiber membranes with an ultra- thin dense selective layer; 3) materials against plasticization; and 4) aging. In each area, we summarize the scientific accomplishments and technical difficulties.

关键词： hollow fiber membranes characterization plasticization aging gas separation

Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2.& JIANG Zonglin2.1. Key Laboratory of high Temperature Gas Dynamics, institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 1. Key Laboratory of high Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Graduate University of Chinese Academy of Sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China 2. Center for Condensed Matter Physics, institute of Physics, Chinese Academy of Sciences, Beijing 100080, China 3. BSRF, institute of {2. Energy Physics, Chinese Academy of Sciences, Beijing 100039, China 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.