Lorenz吸引子的微观结构

轨迹保稳降维是一种分析高维非线性系统稳定性的方法。其要点是先在高维空问中求取轨迹；再将F轨迹映射为n-1个R^2映像，并在变换中严格保持感兴趣的稳定特性：分析各映像轨迹的稳定性：最后聚合为原轨迹特性的描述。本文按此分析Lorenz吸引子的结构稳定性。例如，将其中的z变量处理为时变参量后，(x,y）子系统成为时变的线性2维系统，可得分岔集{zcr}及奇点特性沿z轴的变化规律。故对于特定的轨迹(x,y,z），可将其在各坐标平面上的投影轨迹分成短线段的有序队列，各相邻线段对应于特性不同的奇点，从而揭示Lorenz吸引子全局分岔的精细结构及其通往高维混沌的道路。     

光纤传感器测量FRP加固结构的损伤

A distributed fiber optic sensor is developed for condition monitoring of civil infrastructure sys-tems. The fiber optic sensor is especially useful in applications involving structures strengthened by fiberreinforced polymer (FRP) composites. The sensor principles are simple and therefore, practical for detec-tion of cracks, debonding and deformation measurements. Structural monitoring capability of the sensor     

SET-VALUED EXTENSION OF OPERATORS VIA STEINER SELECTIONS(Ⅱ)-APPLICATIONS TO APPROXIMATION

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎＰａｒｔⅠｏｆｔｈｉｓｓｅｒｉｅｓ (ｓｅｅ [1 ] )ｗｅｐｒｏｐｏｓｅａｍｅｔｈｏｄｔｏｅｘｔｅｎｄａｎｏｐｅｒａｔｏｒＴｄｅｆｉｎｅｄｉｎａｓｐａｃｅｏｆｃｏｎｔｉｎｕｏｕｓｆｕｎｃｔｉｏｎｓｔｏａｎｏｐｅｒａｔｏｒＴ ｄｅｆｉｎｅｄｉｎａｓｐａｃｅｏｆｃｏｎｔｉｎｕｏｕｓｓｅｔ＿ｖａｌｕｅｄｆｕｎｃｔｉｏｎｓ ,ｖｉａＳｔｅｉｎｅｒｓｅｌｅｃｔｉｏｎｓ.Ｗｅｓｔｕｄｙｓｏｍｅｐｒｏｐｅｒｔｉｅｓｏｆｔｈｉｓｅｘｔｅｎｓｉｏｎａｎｄａｌｓｏｗｅａｎａｌｙｚｅｓｏｍｅｒｅｌ…     

THE THEORETICAL COST OF SEQUENTIAL AND PARALLEL ALGORITHMS FOR SOLVING LINEAR SYSTEMS OF EQUATIONS

ＴＨＥ　ＴＨＥＯＲＥＴＩＣＡＬ　ＣＯＳＴ　ＯＦ　ＳＥＱＵＥＮＴＩＡＬ　ＡＮＤ　ＰＡＲＡＬＬＥＬ　ＡＬＧＯＲＩＴＨＭＳ　ＦＯＲ　ＳＯＬＶＩＮＧ　ＬＩＮＥＡＲ　ＳＹＳＴＥＭＳ　ＯＦ　ＥＱＵＡＴＩＯＮＳＳａｌｍａｎＨ．Ａｂｂａｓ（ＲｅｃｅｉｖｅｄＭａｙ２４...     

《现代连续统物理丛书》中译本序

中国力学学会理性力学与力学中数学方法专业组,一九七九年八月在兰州大学举办的第一次理性力学讲学讨论会上,共同商定组织翻译由美国普林斯登大学A.C.Eringen 教授主编的《连续统物理》卷1至卷4,共分十七册.争取在今明两年来陆续出版,以利于推进我国理性力学的发展.今得江苏科技出版社的大力支持,《丛书》即将和广大读者见面了.原主编A.C.Eringen教授曾在一九八○年夏亲自来我国讲学(微极场论和非局部场论),并亲自撰就中译本版序,为《丛书》在我国翻译出版给予了热情支持.《丛书》分册目录和中译本序如下:第一分册张量分析:第二分册群论:第三分册不变量理论:第四分册泛函分...     

Piecewise analysis of oblique vibro-impacting systems

A great number of studies have shown the complex nonlinear dynamics of mechanical systems with repeated normal impacts. An oblique frictional impact introduces even more complicated dynamics such as stick-slip motions to those systems. Hence, the dynamics of oblique vibro-impacting systems with possible sliding motion is an open problem. Based on a hybrid analysis of vibro-impact dynamics, kinematics and complementary conditions, a piecewise analysis method is developed in the paper to describe the sliding motion during an oblique impact. Thereby, a parametrically excited planar pendulum between two parallel rigid walls is studied as an illustrative example. The example, together with the corresponding numerical results, shows that the sliding impacts occur in such a system with a set of properly selected parameters. The project supported by the National Natural Science Foundation of China (59905010) and by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education, China     

CHARACTERIZATION OF POWDER FLOWABILITY USING MEASUREMENT OF ANGLE OF REPOSE

In response to the need in industry for a quick and reproducible method of measuring the flowability of powders in processes involving transport and storage, the apparently simple idea of measuring angle of repose has been revived. The simple tester first used has evolved over a number of years into the present version which is shown to be capable of handling quite small samples of powders that are even slightly cohesive. Experimental data are presented and results shown to compare consistently with the better known Hausner ratio.     

VERIFICATION OF SMOM AND QMOM POPULATION BALANCE MODELING IN CFD CODE USING ANALYTICAL SOLUTIONS FOR BATCH PARTICULATE PROCESSES

For many processes of industrial significance, due to the strong coupling between particle interactions and fluid dynamics, the population balance must be solved as part of a computational fluid dynamics （CFD） simulation. In this work, a CFD based population balance model is tested using a batch crystallization reactor. In this CFD model, the population balance is solved by the standard method of moments （SMOM） and the quadrature method of moments （QMOM）. The results of these simulations are compared to analytical solutions for the population balance in a batch tank where 1） nucleation, 2） growth, 3） aggregation, and 4） breakage are taking place separately. The results of these comparisons show that the first 6 moments of the population balance are accurately predicted for nucleation, growth, aggregation and breakage at all times.     

GENERALIZATION OF STEINER FORMULAFOR THE HOMOTHETIC MOTIONS ONTHE PLANAR KINEMATICS

The Steiner formula and the mixture area formula given by M(U|¨)ller were expressed under the one-parameter closed planar homothetic motions in the complex sense . Also, using the generalization of Steiner formula, the result of Holditch theorem for homothetic motions is got. In the case of the homothetic scale h≡1 the results given by M(U|¨)ller are obtained as a special case.     

A DEVELOPMENT OF BEM TO TWO DIMENSIONAL ELASTICITY

This paper presents a new boundary integral equatiòn for two-dimensional elasticity with the stress component σ_(ij)t_it_j as one of the boundary values,where t_i is the direction cosine of the tangent on the boundary.This form of BEM hasan advantage in that the stress component σ_(ij)t_it_j on the boundary can be calculateddirectly from the numerical solution.The present formulation for plane problems usestwo kernels,the one is logarithmically singular and the other is 1/r singular.Theeffectiveness of the approach is also discussed through test examples.