主问题

The general analysis is focused on insulation level of the autotransformer neutraland the entrance of the autotransformer after small reactance grounding. In addition, the impedancevalue of the small reactance, the protection of the neutral and autotransformer entrance, and insulation coordination is particular discussed.

本文将对500kV 自耦变中性点由直接接地改成经小电抗接地的方式后，在多种不同的运行方式下，对其中性点、主变入口处上出现的过电压进行了详细全面的分析，并在此基础上对中性点电抗器的小电抗取值、主变中性点和主变入口处的过电压保护和绝缘配合问题进行了探讨。

The micro vehicle rear axle of car main gear box noise question became the worker matter of concern. In this paper, the micro vehicle rear axle of car main gear box noise performance present situation and the traditional assessment method are discussed, and the general BP neural network and the Levenberg-Marguardt algorithm are introduced in detail. Improves the BP neural network using the LM algorithm, at present is trains the neural network the quickest algorithm.

微车后桥主减速器噪声问题成为工作者所关注的问题，本文介绍了后桥主减速器噪声性能现状及传统评价方法，阐述了BP神经网络的一般算法，并详细介绍了Levenberg-Marguardt算法，利用LM算法来改进BP神经网络，目前是训练神经网络的最快算法。

For the Riemann boundary value problems for the first order elliptic systems , we translates them to equivalent singular integral equations and proves the existence of the solution to the discussed problems under some assumptions by means of generalized analytic function theory , singular integral equation theory , contract principle or generaliezed contract principle ; For the Riemann-Hilbert boundary value problems for the first order elliptic systems , we proves the problems solvable under some assumptions by means of generalized analytic function theory , Cauchy integral formula , function theoretic approaches and fixed point theorem ; the boundary element method for the Riemann-Hilbert boundary value problems for the generalized analytic function , we obtains the boundary integral equations by means of the generalized Cauchy integral formula of the generalized analytic function , introducing Cauchy principal value integration , dispersing the boundary of the area , and we obtains the solution to the problems using the boundary conditions .

对于一阶椭圆型方程组的Riemann边值问题，是通过把它们转化为与原问题等价的奇异积分方程，利用广义解析函数理论、奇异积分方程理论、压缩原理或广义压缩原理，证明在某些假设条件下所讨论问题的解的存在性；对于一阶椭圆型方程组的Riemann-Hilbert边值问题，利用广义解析函数理论、Cauchy积分公式、函数论方法和不动点原理，证明在某些假设条件下所讨论问题的可解性；广义解析函数的Riemann-Hilbert边值问题的边界元方法是利用广义解析函数的广义Cauchy积分公式，引入Cauchy主值积分，通过对区域边界的离散化，得到边界积分方程，再利用边界条件得到问题的解。

At last, through the analysis of the T-stress, it is concluded that the T-stress plays an important role for the oriented microcrack cases. It is necessary to consider the effect of the T-stress in determining the shielding or amplification effect of the oriented microcracks.

最后，本文采用离散模型研究了各向异性材料主微裂纹干涉问题中T应力对主裂尖应力强度因子的影响：T应力对主裂尖应力强度因子的影响是不能被忽视的，这种影响不但与微裂纹的几何分布有关，而且还与T应力的大小和符号有关。

Parts of current parallel databases support expanding of data types, but all of them lack of theoretical foundation. It is difficult to predicate the performances of parallel query, complicated to optimize parallel query and unattainable to keep the correctness of parallel query optimization This thesis, for the first time, combines monoid algebra system with BSP parallel model systematically, and provides a general-purpose parallel object-relational database systems-PORDBMS.

文章系统地研究了资源分配问题的分解协调理论与方法，给出了非线性分解式模型的构造和有效的求解方法，其中对主问题提出了适应性较强的修正算法，可用于一些难于公式化的问题的模型构造与求解，逐步寻优策略可有效地求解非线性关联约束优化问题。

Based on the former study of soils constitutive relation involving principal stress axes rotation,the influences of principal stress axes rotation on the distribution of stress and deformation of soils are provided through numerical simulation of plane strain problems of soils involving rotation of principal stress axes.

在含主应力轴旋转的土体本构关系研究的基础上，通过含主应力轴旋转的土体平面应变问题的弹塑性数值模拟结果分析，总结主应力轴旋转对土体应力分布与变形影响的规律，得出需要考虑主应力轴旋转的条件及其影响的相对大小。

And the frontal technique is adapted to solve the FE equations. The techniques are studied to deal with the large slip frictional contactproblems between a deflectable body with large deformation and a rigid bodywith flat or curved surface. A new algorithm is presented to resolve such contactproblems, including incremental displacement constraints and force constraints,and the modules are programmed. The performances of tire under static load invertical loading state and camber state are analyzed by this method. And theexperiments were carried out at the same condition as used in analysis process.

研究了大变形柔性体与具有平面及曲面外形刚性体之间的大滑动摩擦接触问题，提出了求解这类接触问题的位移增量约束和主动力增量约束处理方法；编制了大变形柔性体与具有平面及曲面外形刚性体之间的大滑动摩擦接触问题求解模块；利用本文提出的大滑移接触问题处理方法，分析了轮胎在径向静载和静态外倾加载条件下受力和变形，并对部分分析结果进行了试验验证，验证结果表明，本文提出的位移增量约束和主动力增量约束处理接触问题的方法是正确可靠的，而且具有精度高、收敛性好、收敛速度快的优点。

We take into account the onedimensional and multidimensional data partition methods, physical storage structures and further more how to parallelize them. And the implementation of primitives and basic algorithms of parallel databases are analyzed and designed.

应用先进的动态规划，网络流规划和分解协调方法，保证了整体的优化效果，可以取得明显的经济效益，并有满意的计算速度，本文提出的主问题解法，可以考虑时变的启动耗量，达到整体算法的一致性，这是以往方法难于办到的。

According to these characters,the model was reformulated in which these corresponding integer and continuous variables appeared in t...

根据问题的特点将原模型分解为含有0-1变量的优化主问题和连续变量的子问题，并提出分解算法，降低了相应连续子规划的规模和复杂度。

The paper describes how the local force of the main web is considered as the force caused by the Contact pressure among the trolley wheel, rail and top flange, and how the contact analysis model for the local force is built by means of both Hertz theory and finite element software ANSYS combined. Also, it analyzes the variation of the local stress under the different conditions and comes to a conclusion, and compares the results derived from the experimental formula with the result from ANSYS.

本论文的主要内容：将Hertz接触理论和有限元软件ANSYS结合起来，把主腹板的局部受力问题视为小车轮与轨道及轨道与上翼缘板之间发生接触行为作用下的受力问题，建立了小车轮压作用处偏轨箱形梁主腹板局部受力的接触分析模型，研究不同情况（小车轮压、箱形梁几何参数和轨道截面惯性矩）下局部应力的变化规律，得出相关结论；最后将经验公式解与ANSYS数值解进行对比分析论证。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。