Computations of two passing‐by high‐speed trains by a relaxation overset‐grid algorithm

This paper presents a relaxation algorithm, which is based on the overset grid technology, an unsteady three‐dimensional Navier–Stokes flow solver, and an inner‐ and outer‐relaxation method, for simulation of the unsteady flows of moving high‐speed trains. The flow solutions on the overlapped grids can be accurately updated by introducing a grid tracking technique and the inner‐ and outer‐relaxation method. To evaluate the capability and solution accuracy of the present algorithm, the computational static pressure distribution of a single stationary TGV high‐speed train inside a long tunnel is investigated numerically, and is compared with the experimental data from low‐speed wind tunnel test. Further, the unsteady flows of two TGV high‐speed trains passing by each other inside a long tunnel and at the tunnel entrance are simulated. A series of time histories of pressure distributions and aerodynamic loads acting on the train and tunnel surfaces are depicted for detailed discussions. Copyright © 2004 John Wiley & Sons, Ltd.     

Uniformity in Computable Structure Theory

We investigate the effects of adding uniformity requirements to concepts in computable structure theory such as computable categoricity (of a structure) and intrinsic computability (of a relation on a computable structure). We consider and compare two different notions of uniformity, previously studied by Kudinov and by Ventsov. We discuss some of their results and establish new ones, while also exploring the connections with the relative computable structure theory of Ash, Knight, Manasse, and Slaman and Chisholm and with previous work of Ash, Knight, and Slaman on uniformity in a general computable structure-theoretical setting.     

内部审核在计量体系中的作用

介绍内部审核制度在计量测试工作中的目的和作用，提出了内部审核工作应注意的事项，如内部审核工作计划的完整性，内部审核工作的有效性，管理者工作内容的全面性，以及后续工作的完善性。     

模糊全区间序结构

本文试图对模糊偏好结构及模糊全区间序结构的定义进行探讨，并讨论它们的性质．以Fodor等提出的公理为基础，给出了模糊偏好结构的定义，同时对一类重要的模糊偏好结构-模糊全区间序结构的性质进行了讨论，得出了模糊全区间序结构的一些充要条件．     

Ground-state complex formation of perylene with pyromellitic dianhydride studied by static fluorescence quenching

The association of complex formation with static quenching in CT systems was investigated. Evaluation of the data made evident that the inner filter effect must be allowed for. Time-resolved and temperature-dependent stationary measurements of fluorescence led to the separation of dynamic and static quenching components. The static quenching constant is discussed with respect to the equilibrium constant of complex formation determined by absorption spectroscopy.     

用三个关系式与Mathematica软件求第二类自然数幂和公式

首先介绍三个第二类自然数幂和关系式并对其中的两式给出证明,接着利用这些关系式与数学软件M athem atica4.0,给出求解第二类自然数幂和公式的若干机械计算方法.     

覆盖广义Rough集中的隶属关系

对覆盖广义Rough集中的隶属关系、隶属函数进行了定义，并利用隶属函数定义了集合的Rough包含与Rough相等，得到一些与Pawlak的Rough集不同的性质。     

Selection Principles and Sierpinski Sets

We show that a set of real numbers is a Sierpinski set if, and only if, it satisfies a selection property similar to the familiar Menger property.     

社会个性与内在自我的平衡——《达罗卫夫人》和《到灯塔去》人物的生存状态

在《达罗卫夫人》和《到灯塔去》两部小说中,伍尔夫探讨了现代人有效的生存状态,与他人的社会交往的同时,主要人物都不忘回归自我,任意识随意流淌,展现完全真实的内在自我,在自我宣泄和与他人交流中达到平衡的生存状态。     

普通高校大学生英语学习焦虑和学习策略的调查研究

学习焦虑和学习策略是英语学习的两个重要因素,它们不仅影响学习者的英语学习,而且内部之间也相互影响。本研究以普通高校大学生为研究对象,调查了大学生的英语学习焦虑和英语学习策略使用情况,并分析了影响英语学习焦虑和英语学习策略使用的因素,以及英语学习焦虑和英语学习策略之间的关系。该研究结果对普通高校的大学英语教学具有实践指导意义。