基本力

By adopting the basic theory of rigid body mechanics, this paper expounds the safe striking range to avoid miscue and the qualitative and quantitative analysis of force of striking and of the cue ball motion.

运用理论力学的基本原理，确定了避免"滑杆"的安全击球范围，对台球击球和主球运动过程中的受力情况，进行了定量计算和定性分析。

In this paper, the principle of molecular dynamics, and the category of molecular force field, and the establishment of AMBER、OPLS and CHARMM force field are introduced.

本文介绍了分子动力学(molecular dynamics， MD)的基本原理，分子力场的种类，以及离子液体分子动力学模拟一般采用的AMBER、OPLS和CHARMM三种力场的构建形式。

Based on Universal Soil Loss Equation and the natural environment characteristics of Fujian Province,four natural factors affecting soil erosion were chosen as the assessment indices,which are the rainfall erosivity,relief,soil texture and vegetation types,and the soil erosion sensitivity of Fujian Province was assessed under the support of GIS.

根据通用土壤流失方程的基本原理，结合福建省的自然环境特征，选择降雨侵蚀力、地形起伏度、土壤质地、植被类型4个自然因子作为评价指标，在G IS软件支持下对福建省土壤侵蚀敏感性进行评价，评价结果综合反映了福建省土壤侵蚀敏感性的分布规律，为土壤侵蚀防治、生态环境保护与建设以及土地资源合理开发利用提供依据。

The nonlinear magnetoelastic kinetic equations, the electrodynamics equations and the expressions of Lorentz force of thin current-carrying plate under the action of the coupled field are given. The normal Cauchy form nonlinear differential equations, which include ten basic unknown functions in all, are obtained by means of variable replacement.

该文在给出载流薄板在耦合场作用下的磁弹性非线性运动方程、电动力学方程和洛仑兹力表达式的基础上，通过变量代换将描述载流薄板的磁弹性状态方程整理成含有10个基本未知函数的标准柯西型。

Then, the fronts .of different intensities are superposed on the orographic disturbances and pushed by basic geostrophic flow to climb over the orography.

通过非静力模式讨论了两维地形扰动与锋面的相互作用，研究了不同基本气流，包括正压、斜压、层结强弱差异，不同尺度的地形，包括不同高度和不同宽度，强弱不同的锋面等多种情况下地形扰动与锋面扰动的相互影响，发现地形尺度和气流的性质不同带来的结果是有差异的，中尺度地形使冷锋在迎风坡锋消，在背风坡则是锋生和锋消相间的波状分布，表现为锋面在山顶附近锋生、快速下坡过程中锋消和山脚处锋生的分布特征，这与半地转模式中地形的动力作用使冷锋在背风侧单纯加强是不同的。

In the parallel program, the in-core and out-of-core algorithms can be identified and chosen to use automatically. So the algorithms are united.(3) The re-orthonormalization technique is used to solve the loss of orthonormality of basis vector during the classical GMRES method solving large-scale three dimensional elasto-static BE problems.

3采用重正交技术解决了经典GMRES方法在求解大型三维弹性静力边界元问题过程中出现的基向量正交性丧失的问题；结合边界元基本解和系数矩阵的特点以及并行化的要求，研究了几种预条件技术；并以重正交技术和预条件技术实现了经典GMRES的实用化。

Our fundamental human drives have not changed from the Paleolithic era, hundreds of thousands of years ago.

人类的基本驱力从旧石器时代以来就没有改变，都几十万年了。

Through a large number of examples in this book describes the basic use of ANSYS 8.1 software methods, including modeling, meshing, applied loads, solving and post-processing, etc.; then introduced using ANSYS finite element analysis process commonly used in high-level analytical methods, such as the non-linear static analysis, modal analysis, transient dynamic analysis, thermodynamic analysis, optimization design, etc.; In addition, the book pairs of ANSYS parametric programming language APDL made an initial set to try to make the reader of this strong preliminary understanding of language.

本书通过大量的实例介绍了ANSYS 8.1软件的基本使用方法，包括建模、网格划分、施加荷载、求解及后处理等；进而介绍了用ANSYS进行有限元分析过程中常用的高级分析方法，如非线性静力分析、模态分析、瞬态动力分析、热力学分析、优化设计等；另外，本书还对ANSYS参数化编程语言APDL作了初步阐述，力图使读者对这种强大的语言有初步的认识。

How to choose strategies of handing traditional culture down is an unavoidable subject in the new situation. The author of the article thinks that clothing, which is believed to be the visiting card of a people, should be simple with symbolization, pictorialization, totems and commercialization. Handing down of the living culture should be combined with ecosystem environments and places of interest to develop its content step by step. One cultural item should be exploited in one place to keep it alive forever. We should make good use of educational, research and translating organizations, media and the Internet to propagandize old and new characters and works. Some museums should be built up to protect metallic and stone relics. Setting up ecological museums or cultural villages and parks is an effective method. We should find out a new way in which key points about the understanding of the culture are explained clearly, core advantages are developed and cutlural labour force and propaganda work are revived The most important thing is to make complete use of the laws and policies on minority self-rule to find out the best way to keep Yi's traditional culture alive.

作者认为，作为民族身份"名片"的服饰应以简明为原则尽量符号化、图案化、图腾化、商业化；作为活文化的仪式与习俗的传承，除了在经济发展的前提下以村寨为基本单位尽量保护和弘扬，要尽可能与生态环境和旅游胜地紧密结合进行单个文化主题的念珠式贯串开发，一地深入开掘一个文化内蕴，使之可以传之久远；依托教育、科研、翻译机构和文艺传媒、互联网传承新老文字及典籍文化，建立文博场馆保护金石文物；建立民族生态博物馆或民族文化村文化园等也不失为一种有效的方式；译解文化传承基因，培育核心发展优势，形成文化再生力传播力，是一条应该认真探索的道路；最重要的是要充分利用好民族区域自治政策法规，使之发挥的效益最大化，并从法律和政策上寻求最佳的传统文化传承策略。

The programs of problems have been developed in FORTRAN based on the theory and methods introduced in this thesis, as following: 1. The finite element and mapping infinite element programs for static problem of plane and spatial infinite domain.

根据文中所涉及的基本原理及计算方法，用Fortran语言编制了求解以下问题的程序： 1 无限域平面及空间静力问题的有限元、映射无限元程序。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。