接触问题

Based on spline function method,the spline finite element formulation for the contact-impact problems is proposed.

文摘：用样条有限元法分析了杆的接触冲击动力响应问题，建立了计算格式，并用算例说明该方法的有效性。

When creating the finite element model, complicated connections among howitzer components are considered, especially the large displacement slide and the nonlinear spring connection between gun tube and cradle rail. The gun firing at 0°direction angle and 0°elevating angle is simulated with explicit time integration method and implicit time integration method, and the similar results are obtained.

在建立有限元模型时，考虑了火炮各部件间复杂连接，尤其是身管与摇架导轨间的大位移滑动接触和非线性弹簧单元连接等非线性问题；分别应用显式积分程序和隐式积分程序模拟了火炮在0°高低射角、0°方向射角工况下的发射过程，得到了相近的结果。

For accuracy and computation cost, the nonlinear finite element structural dynamics model of the naval gun is created with different elements such as solid elements, shell elements and the nonlinear components are considered, especially the large displacement slide and the nonlinear spring connection between gun tube and cradle rail.

在建立有限元模型时，考虑了火炮各部件间复杂连接，尤其是身管与摇架间的大位移滑动接触的非线性问题。

When run-time panels, due to sliding contact with the glass, so a good run; and when the newly built run-time stamp machine, so as a result of man-made and glass sliding leads to loose a few initial scans do not a problem.

当打开面板运行时，由于滑片不与玻璃接触，所以运行很好；而当刚刚盖上机盖运行时，由于人为的使滑片与玻璃间产生松动，最初的几次扫描也不会有问题。

My family is in touch with you every day, so don't talk to me about surface area.

我的家庭每天都和你接触，所以请不要和我讨论这些表面问题。

The burn of circuit breaker closing coils and contactors is a common problem in the switchyard operates.

断路器控制回路的合闸线圈和接触器烧毁现象是变电运行工作中经常遇到的普遍问题。

Telepathy is very important now, for this way you can tangibly be in touch with your guidance and since you are in touch, you will be able to keep your balance and get your questions answered immediately.

现在心灵感应是非常重要的，因为这方式你们能够明白同你们的教导有联系和自从你们是在接触中，你们将会保持你们的平衡而立刻得到你们问题的解答。

The projects are supported by National Nature Science Foundation of China. In the thesis, we take the heat transfer analysis of 3D interfacial layer of two contact solids as a cut-in point and investigates the visualization simulation of 3D ITR in the condition of vacuum and micro therm.

本文结合国家自然科学基金项目，以两接触物体的三维界面层为研究的切入点，研究真空低温环境下三维界面层热阻的可视化仿真问题。

The research work of this paper is divided into five parts: The first ,according to the work characteristics of ship's auxiliary boiler, this paper is to design applied project in the automatic control system of ship's auxiliary boiler; The second, according to the work request of the cargo winch of alternating three-speed change-pole speed-adjusting, this paper is to determine adopting the method of the PLC control; The third, this paper is to design PLC application in three -phase induction motor control, to give the ladder chart, program and input and output circuit diagram; The fourth, this paper is to research the method of the ship's combined starting screen automatic control with the PLC; The fifth, this paper is to inquire the possibility of apply the PLC in ship's engine room surveillance system; According to the comprehensive analysis of above actual example of ship's auxiliary machinery automatic system with the technique of PLC; not only can use the technique of PLC to replace traditional relay-contactor control technique in ship's auxiliary machinery automatic system, but also can get the conclusion of the former is more dependable and more clever than the latter, the maintenance is more convenient, thus develop a new path for ship automation.

本文研究的工作主要包括五个部分：第一，根据船舶辅锅炉的工作特点，设计PLC在船舶辅锅炉自动控制系统中的应用方案，主要有PLC选型及输入输出点的设计，画出系统控制梯形图并分析工作原理；第二，根据交流三速变极调速起货机的工作要求，确定采用PLC控制的方法，进行控制系统的硬件设计和软件设计，并分析工作原理：第三，设计了PLC在三相异步电动机控制中的应用，给出了控制梯形图、程序及输入、输出接线图；第四，研究了用PLC实现船舶组合起动屏自动控制的方法，进行了系统的电源设计和软件设计，给出系统工作流程图；第五，探讨了船舶机舱监视系统应用PLC的可行性，将继电器报警线路改为用PLC控制报警，给出系统硬件图和软件梯形图，并分析了PLC机的选型、抗干扰和应用PLC的经济效益和社会效益等问题。综合以上船舶辅助机械自动控制系统采用PLC技术的实例分析，可以得出船舶辅助机械自动控制系统不但可以使用PLC技术取代传统的继电器接触器控制技术，而且前者比后者更可靠、更小巧，维护保养更方便的结论，从而为船舶自动化开辟了一条新的路径。无忧毕业设计网 www.5ubs.cn

Your article doesn't touch on the heart of the subject.

你的文章没接触到问题的关键

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷