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It is different from the finite element method which uses the calculus of variation to construct the element-based approximate equilibrium equation. It does consider the equilibriums of forces on the inter-element boundary, which are neglected in the finite element method through the weak formulation.

这种方法跟有限元素法不同，因为有限元素法是采用变分法建立各个元素的近似平衡方程式，这种方法也考虑元素与元素相连接的边界上的力平衡条件，而在有限元素法的推导过程中我们忽略了这种条件。

Incurrent research, aiming at the rupture problem engendered in the shooting process of acertain 5.56mm automatic rifle, the strain and stress distributions on the cartridge caseunder the action of axial pull have been analyzed. Based on the theories of elastic-plasticmechanics and contact mechanics, a mathematic and physical model of the cartridge-caseand chamber system has been set up; and based on the platform of the general softwarepackage APDL of ANSYS for finite element analysis, a parameterized model of thecartridge-case and chamber system has also been established. The method for nonlinearFEA has been adopted to analyze the stress distribution on the entire cartridge-case andchamber system, and the method of contact element has been employed to investigate thecontact stress between the cartridge case and chamber, and then the influences of frictioncoefficient and locking space on the static and dynamic stress and strain response of thecartridge case and chamber to the action of power gas have also been discussed. On thebasis of a lot of numerical tests, a kind of element Plane13, which is concentrated incoupled computation of heat and construction, has been used finally to simulate thetransient response of the cartridge-case and chamber system to the power gas. Throughloading the temporary thermal characteristics of explosive gas in the procedure of emulate, the corresponding transient thermal stress distributed on the entire system under thecombined load of transient thermal stress and transient pressure has been obtained. Owingto these comprehensive considerations, the numerical results obtained in this paperrepresent the actual situations comparatively exactly.

本文针对某5.56mm自动步枪在工作中出现断壳的问题，分析了弹壳在轴向拉力作用下的应力应变；基于弹塑性力学及接触理论，建立了弹壳弹膛系统的数学、物理学模型，在通用有限元ANSYS软件的参数化建模工具APDL平台上，建立了弹壳弹膛系统的参数化模型；采用非线性有限元法计算了弹壳弹膛系统的整体应力，引入接触单元法分析弹壳和弹膛的接触压力，探讨了在不同的摩擦系数和不同的闭锁间隙对弹壳弹膛静、动态响应的影响；本文进行了大量的尝试，最后确定采用热、结构耦合单元Plane13，在计算中加载了火药气体的温度历程，成功的获得了弹壳弹膛系统在瞬态的热载荷和瞬态的压力载荷同时作用下弹壳弹膛系统的热应力数值解，考虑因素全面，比较真实的反映了弹壳弹膛系统在火药气体压力和热载荷下作用的情况。

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

The main problems researched in the dissertation and achievements are as follows: The dissertation explains the science background and the theoretical and actual meaning of the task. The progress and the problems of the flow imaging technique are briefly explained. The advantages of electrical capacitance tomography are discussed. The paper discusses the formation and operating principle of ECT, and builds up the definite mathematical model by detail theoretical analyse, and establishes the Finite Element Model of the system by changing the finite boundary value problem of ECT into equivalence variation problem according to variation principle. On the basis of the FEM of the system, the paper builds the finite element model of the capacitance sensitivity field distribution and programs its finite element simulation software and proves the validity of the FEM of the ECT from different aspects. With the FEM and the qualitative analyse of the effect of each structural parameter of the capacitance transducer on its capability, this paper optimizes the structural parameters of the capacitance transducer, and obviously improves its capability. The compare of the simulated result with the static experimental result shows that the error of them is less than 0.9%.

其主要研究内容包括：阐述课题研究的学术背景及其理论与实际意义，概括总结出流动层析成像技术的发展现状和存在的问题，指出电容层析成像技术的优点；讨论电容层析成像系统的组成及工作原理，进行详尽的理论分析，以变分原理为基础，将ECT的有限元边值问题转换为等价的变分问题，从而建立系统的有限元模型；在系统有限元模型的基础上，建立敏感场的数学模型，编制有限元的仿真软件，并从不同角度证明电容层析成像系统有限元模型的正确性；利用有限元模型，定性地分析电容传感器各结构参数对其性能的影响，并对传感器结构参数进行优化设计，使其性能得到明显的改善。8电极ECT系统的仿真和静态实验结果的比较表明，它们之间的相对误差小于0。

This paper, which focused on the structure optimization theory and method, has finished such studies as follows: The three dimension model has been built, which provide the necessary conditions for the building of the dynamics equivalent model. By the launch dynamics simulation, the loads of the key joints when the rocket is launched has been got, which provide the necessary data for the finite element analysis and the structure optimization. The finite element model of the excess weight parts of the rocket has been built, buy the finite element intension analysis of the model in two conditions, the displacement and the stress of the key points have been got, which make us know the distributing of the stress and the transmogrification of the part. To satisfy the intension and the precision design request and to decrease the weight of the part as many as possible, the part has been topology optimized by the structure optimization theory and method. After that, the new model has been analysis in structure and launch dynamics. The contrast of the character change of the old part and the new part and the influence on the rocket system have been studied.

本文以结构优化理论和方法为核心，主要做了以下工作：建立了某自行火箭炮全炮三维实体模型，为建立该火箭炮系统的动力学等效模型提供了必要条件，进行了发射动力学仿真，得到该火箭炮发射装置各关键连接部位在发射状态下的载荷，为有限元分析和结构优化提供了必需的数据；建立了该火箭炮发射装置超重部分的有限元模型，分两种工况，对模型进行了有限元强度分析，得出了关键部位的位移和应力值，对其的应力和变形分布有了具体的了解；运用结构优化的理论和方法，对该火箭炮发射装置超重部分进行了拓扑优化，使其在满足强度和精度的要求下尽可能多地减轻重量，对优化后得到的模型进行了结构分析和发射动力学分析，对比了该部件优化前后的特性变化以及对火箭炮系统的影响。

This paper deals with and summarizes the research and importance of ductile shear zones and presents the future direction and aim for the research of the ductile shear zones around the world. Four aspects of studies of the ductile shear zones have been proposed in this paper as follows:(1) The stress environment including the mineral assemblages, deformation, stress-shearing parameters;(2) The major element sequence and activation under condition of stress;(3) The variations of trace elements and REE, their transportation distributions under strong natural deformation as well as variations of mineral crystal parameters, which can also control the element changes during the ductile deformation;(4) The relationship between element migrations, activation and stress, which will present the new evidences for the studies of dynamic diagenesis and mineralization as well as the studies of evolution of ductile shear zones developed in middle and low levels.(5) The analysis of elements and isotopes in mylonites on the micro-scale are crucial for the understanding of component migrations during the mylonization.

对韧性剪切带及其变形岩石的研究现状和研究意义进行系统的综述，提出了未来韧性剪切带及其糜棱岩的研究方向和目标：①系统研究糜棱岩中主要造岩矿物组合及其变形特征，计算剪切变形岩石的应力－应变参数，搞清韧性剪切带所处的应力应变环境；②系统研究韧性剪切带岩石在天然分强剪切应力作用条件下常量元素迁移机制及活化转移的应力排序问题；③系统研究剪切变形作用过程中岩石化学组成的微量和稀土元素变化，讨论强变形条件下岩石中微量元素活化和迁移规律，深入探讨微量元素迁移的动力控制，包括稀土元素配分变化的应力制约以及应变矿物晶格化学变化行为及其对其寄主的变形岩石元素在应变过程中迁移变化的制约和影响；④从理论上探讨天然强剪切应变条件下岩石中组分活化、转移与应力的因果联系，为深入探讨韧性剪切带动力成岩作用提供理论的科学依据，为探讨中、下地壳中韧性剪切带的形成和演化提供科学依据，同时为韧性剪切变形作用条件下成岩、成矿地球化学作用提供理论和实验依据；⑤现代分析技术如激光同位素原位分析以及激光ICP-MASS分析技术对研究变形域内的岩石的元素和同位素的活化迁移规律，对深刻揭示糜棱岩化过程中的元素活化迁移机制提供更高质量的地球化学证据具有重要的作用。

This article, based on key technique and different objective conditions in terms of geography and geology, such as soft soils, shallow water, and heavy sludge seen in ChangHong tunnel, presents features of key construction technique in ChangHong Project, such as slope stability and bottom settlement control in dry dock, cracks control and freeboard control technique respectively for element fabrication, pile foundation construction, and piles-tube connection technique, such technique like, sludge cleanup in immersion trench, and element sinking/positioning technique together with element joint (including connection to abutment and final joint).

文章根据沉管隧道工程建设的关键技术和宁波常洪隧道工程土软、水浅、淤重等客观地质地理环境条件，介绍了宁波常洪沉管隧道工程的施工技术特点，如干坞边坡稳定和管底基础变形的控制技术、本体防水混凝土管段制作的裂缝和干舷控制技术、管段江中桩基基础的施工和其与管底连接的技术工艺、管段基槽清淤和沉放定位施工技术，以及管段接头连接（包括与岸边段的连接和最终接头）的施工技术等。

This article, based on key technique and different objective conditions in terms of geography and geology, such as soft soils, shallow water, and heavy sludge seen in ChangHong tunnel, presents features of key construction technique in ChangHong Project, such as slope stability and bottom settlement control in dry dock, cracks control and freeboard control technique respectively for element fabrication, pile foundation construction, and piles-tube connection technique, such technique like, sludge cleanup in immersion trench, and element sinking/positioning technique together with element joint (including connection to abutment and final joint).

本文根据沉管隧道工程建设的关键技术和宁波常洪隧道工程土软、水浅、淤重等客观地质地理环境条件，介绍了沉管隧道工程的施工技术特点，如干坞边坡稳定和管底基础变形的控制技术、本体防水混凝土管段制作的裂缝和干舷控制技术、管段江中桩基基础的施工和其与管底连接的技术工艺、管段基槽清淤和沉放定位施工技术，以及管段接头连接（包括与岸边段的连接和最终接头）的施工技术等。

This article, based on key technique and different objective conditions in terms of geography and geology, such as soft soils, shallow water, and heavy sludge seen in ChangHong tunnel, presents features of key construction technique in ChangHong Project, such as slope stability and bottom settlement control in dry dock, cracks control and freeboard control technique respectively for element fabrication, pile foundation construction, and piles-tube connection technique, such technique like, sludge cleanup in immersion trench, and element sinking/positioning technique together with element joint (including connection to abutment and final joint).

本文根据沉管隧道工程建设的关键技术和宁波常洪隧道工程土软、水浅、淤重等客观地质地理环境条件，介绍了沉管隧道工程的施工技术特点，如干坞边坡稳定和管底基础变形的控制技术、本体防水混凝土管段制作的裂缝和干舷控制技术、管段江中桩基基础的施工和其与管底连接的技术工艺、管段基槽清淤和沉放定位施工技术，以及管段接头连接（包括与岸边段的连接和最终接头）的施工技术等。中国诺宇综合网http：//www.siaaa.com

This article, based on key technique and different objective conditions in terms of geography and geology, such as soft soils, shallow water, and heavy sludge seen in ChangHong tunnel, presents features of key construction technique in ChangHong Project, such as slope stability and bottom settlement control in dry dock, cracks control and freeboard control technique respectively for element fabrication, pile foundation construction, and piles-tube connection technique, such technique like, sludge cleanup in immersion trench, and element sinking/positioning technique together with element joint (including connection to abutment and final joint).

本文根据沉管隧道工程建设的关键技术和宁波常洪隧道工程土软、水浅、淤重等客观地质地理环境条件，介绍了沉管隧道工程的施工技术特点，如干坞边坡稳定和管底基础变形的控制技术、本体防水混凝土管段制作的裂缝和干舷控制技术、管段江中桩基基础的施工和其与管底连接的技术工艺、管段基槽清淤和沉放定位施工技术，以及管段接头连接（包括与岸边段的连接和最终接头）的施工技术等。中国论文联盟http：//www.lwlm.com

We were cousins—his grandfather was King of Scots,and his great-grandfather was Henry VII of England.

我们是堂姐弟——他的祖父曾是苏格兰国王，他的曾祖父是英格兰的亨利二世。

I do want to help you, but I am in a quandary now!

我是想帮你，但是我现在左右为难啊！