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The numerical study is carried out for a KVLCC2 tanker. Firstly, for the ship in oblique motion in deep water, determination of the computational domain, check of the grid dependence and selection of the turbulence model in numerical simulation are investigated. The effectivity of the numerical method is validated by comparing the numerical results with experimental data published in literature and the experimental results obtained by oblique towing test in the towing tank of Shanghai Jiao Tong University.

以KVLCC2大型油轮为研究对象，首先对船舶深水斜航运动粘性流计算中计算区域的确定、网格依赖性的检验以及湍流模型的选取等问题进行研究，通过将本文数值计算结果与他人的试验结果和在上海交通大学拖曳水池进行的船模斜拖试验结果相比较，验证了本文数值方法的有效性。

Every industrialized country lists the numerical control technology and numerical control equipment as country's critical materials besides in the world, not only come to develop self numerical control technology and their estate adopting an important measure, and the effectuation blockades and restricts policy in the respect of the numerical control key technology and equipment "high-grade , precise , and advanced" to our country

此外世界上各工业发达国家还将数控技术及数控装备列为国家的战略物资，不仅采取重大措施来发展自己的数控技术及其产业，而且在"高精尖"数控关键技术和装备方面对我国实行封锁和限制政策

Second order incident boundary condition on fixed incident boundary is derived for numerical simulations, based on the cnoidal or sinusoidal motions of wave maker paddle, which shows that the prediction with second order incident boundary condition is more accurate than the prediction with first order incident boundary condition. 2 The analytical solution for higher-order Boussinesq equations is derived and its applicable range is discussed. 3 A 2-D fully non-linear numerical model using boundary element method is developed to obtain wave forces acting on rectangular obstacle. 4 The three-dimensional fully non-linear waves are studied in a numerical wave tank using finite element method.The studies on the coupled numerical model combined Boussinesq equations with Laplace equation are following.

非耦合非线性波浪计算模型：1 根据造波板做椭圆余弦运动或正弦运动速度，推导出数值模拟波浪水槽时固定入射边界上的二阶波浪入射边界条件，数值计算结果和实验结果的对比表明采用二阶入射边界条件对波面升高的预报比采用一阶入射边界条件对波面升高的预报更为精确；2 推导了波浪水槽造波板做正弦运动所产生波浪的高阶Boussinesq方程摄动展开解析解，讨论了该解析解的适用范围；3 对整个波浪水槽应用边界元方法数值模拟了波浪对物体的非线性作用；4 用有限元法求解三维Laplace方程模拟了三维完全非线性波浪水槽。

The development direction changed direction according to the four-wheeler, the domestic and international company changes direction organization to control to the four-wheeler currently main adoption of is a numeral control, this is owing to a lot of advantages of numerical control:the procedure turn a control, the controller carries on the processing of operation and numerical information according to the control regulation designed, mainly passing procedure to carry out, if change control regulation need to change software, but need not change the hardware structure of system: control the accuracy is high, in the emulation the control the system, the accuracy of the controller from the accuracy of the component but settle, numerical controller accuracy from word long decision;Stability good;The software replies to use, needing a hardware environment of using the homology realization in the emulation the system, the numerical controller is a procedure control, the sub- procedure mold piece which need to be designed and write to carry out its model, can immediately carry out several links of functions expediently.

目前各个厂家大多采用的是PLC、单片机应用于四轮转向控制器中，功能基本能够实现，相比较之下，信号处理能力较强的数字信号处理器各方面均性能优于以上三种处理器。DSP是新世纪数字化革命的核心。它是一种独特的微处理器，具有可编程性，且实时运行速度远远超过通用微处理器。强大的数据处理能力和高速的运行速度，是DSP最值得称道的两大特色。DSP芯片是一种特别适合进行数字信号处理的微处理器。它强调运算处理的实时性，因此除了具备普通微处理器所强调的高速运算和控制功能外，主要针对实时数字信号处理，在处理器结构、指令系统和数据流程上做了很大的改动。它具有灵活、精确、可靠性好、体积小、功耗低和易于大规模集成等优点。

This paper analyzes the numerical control DC constant current source system design needs, expounded numerical-controlled DC constant current source of the hardware and software design principles, instructed the numerical-controlled DC constant current source circuit of the module function and design ideas, completed the numerical-controlled DC current source of all design, and the circuit is complete and procedures.

本文主要分析了数控直流恒流源系统的设计需求，阐述了数控直流恒流源的软硬件的设计原则，介绍了数控直流恒流源各模块电路的功能及设计思路，完成了数控直流恒流源系统的全部设计，给出了完整的电路图和程序。

But in the numerical calculation process, such as numerical differentiation, if we use these numerical methods inadequately, then it may be induced non necessary numerical error, including round off and truncation error.

因而常必须以值方法替代解析解，但是在值计算的过程中，很容引入额外的计算误差，包括舍位误差与截断误差。

In chapter5, the serial properties of numerical range of operator polynomial are put firstly. Secondly, the relation between numerical range of operator polynomial and n-numerical range are considered. Thirdly, in the light of matrix norm, matrix singular value, the regions and bounds of numerical range and spectrum of operator polynomial are dicussed carefully.

第五章研究了算子多项式数值域的性质、算子多项式数值域与n-次数值域的关系，特别地利用矩阵范数、矩阵的奇异值、非负矩阵的理论、友矩阵为工具，给出了算子多项式数值域及谱的范围全面刻画，并深刻地研究了算子线性束的正则性的等价条件及谱分布。

The objective of this study is aimed at the implementation of parallelized numerical quadrature routines. The algorithm we choose for numerical quadrature routines is the so called "Adaptive Romberg Tree integration scheme"(abbr."ARTint") proposed by Lin et. al.[1997]. This numerical quadrature scheme can arrange the function evaluation points adaptively in accordance with characteristic of the trend of variation in integrand function values. When the accuracy of the numerical quadrature value is requested to be increased, a newer and larger set of function evaluation points must be incurred. The main advantage of ARTint method is the inclusion of all function evaluation points used in previous stages. It is this feature of ARTint method that makes it a quadratue scheme with prominent computation efficiency.

本研究在探讨数值积分程式之平行化，所使用的演算法为林聪悟与林佳慧[1997]一书所提出的「Romberg树自动布点数值积分」架构，此一数值积分方法能以适应被积函数值变化情形方式自动安排积分点来进行数值求积计算，在提高阶数以获得更高精度积分值的过程中，此一方法只须再计算新增加积分点的函数值，搭配先前已计算过的函数值的重覆运用即可获得更精确的数值积分估计值，如此将能减少升阶过程中函数求值计算的次数，有效率地完成单重积分的数值计算。

In this thesis, I summarize the theoretical calculation method, applied scope and notice of siphonic drainage system, and point out the advantage of siphonic drainage system compared with gravitation drainage system. In the archetype experiment study of siphonic drainage tube, I adopt different tube diameter and different structural height to survey the drainage volume and press in different place. I observe various kinds of flow state, and get chief factors which influence hydraulic peculiarity of system as the tube diameter or structural height, and find out the relevance of factor to flux. I apply CFD Fluent software and adopt standard k-ε model and RNG k-ε model, then use finite volume method and second-order upwind scheme to discrete numerical model, while coupling numeration of velocity field and press is based on SIMPLE. In the numerical simulation of curved part of tube, siphonic drainage tube experiment system and multi-outlet siphonic drainage system, I make research on internal velocity and press of system in different project condition by changing the tube diameter of curved part, negative press value in tube export and improving the quantity of water gutter. This thesis first adopts a method of combining archetype experiment and numerical simulation to study the siphonic drainage system, test and verify the validity of experiment and numerical simulation, and makefurther study on system, it solves the problems of limited testing conditions, and has a logical results, it can provide a valid method for optimizing and designing the drainage tube-net system. The conclusion have referring value for study and design of siphonic drainage system.

本文首先对虹吸式排水系统理论计算方法、适用范围以及注意事项做出总结，并分析了虹吸式排水系统的优势；再对虹吸式排水管道进行原型试验研究，采用不同管径不同立管高度，对系统流量、管道压强进行量测，观察了各种工况下的流态，对其水力特性进行研究分析，找出影响水力特性的落差、管径主要因素以及与排水量的关系；进一步应用计算流体力学Fluent软件，采用标准κ-ε模型与RNGκ-ε模型，计算过程应用有限体积法和二阶迎风格式对数值模型进行离散，速度和压力的耦合采用SIMPLE算法，分别对系统弯管段、虹吸排水管道试验系统、多斗虹吸式排水系统进行数值模拟分析，通过改变管段弯头处半径、管段出口负压值、增加雨水斗数对不同工况下系统内部的速度和压力进行研究；本文首次采用结合原型试验与数值模拟相结合的方法，对虹吸式屋面雨水排水系统进行研究，试验与模拟相互验证，并进行拓展，很好地解决了虹吸式屋面雨水排水系统由于试验条件限制问题，结果正确合理，为排水管网系统设计和优化研究提供了有效的方法，对工程设计有较好的参考价值。

The company is in line with " the product has no limits, the principle that based on sincerity and pursue being outstanding ", invest the numerical control woodworking machinery trade meticulously, besides researching and developing the products that numerical control woodwork engraves the milling machine , numerical control and carves the milling machine , three major series and a dozen specifications of numerical control carving machine, having developed 10 axle cantilever woodwork machining centers again recently, the real wooden door, special-purpose bull of wave board engraved the milling machine , changed a one hundred sheets of woodwork and engraved the milling machine automatically, multicipital workingbench movement woodwork engraves professional equipment , such as milling machine ,etc..

公司本着&品无止境，诚信为本，追求卓越&的原则，精心投入数控木工机械行业，除研发出数控木工镂铣机、数控雕铣机、数控雕刻机三大系列十几个规格的产品外，近期又研制了10轴悬臂木工加工中心，实木门、波浪板专用多头镂铣机、自动换刀木工镂铣机，多头工作台运动木工镂铣机等专业设备。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。