排序方式: 共有6条查询结果,搜索用时 0 毫秒
1
1.
刘美丽 《自动化技术与应用》2010,29(10):15-18
本课题以汽车运动控制系统的设计为应用背景,利用MATLAB语言对其进行设计与仿真。首先对汽车的运动原理进行分析,建立控制系统模型,确定期望的静态指标(稳态误差)和动态指标(超调量和上升时间),最终应用MATLAB环境下的.m文件来实现汽车运动控制系统的设计。其中,.m文件用step(s)语句来绘制阶跃响应曲线,根据曲线中指标的变化进行PID校正。 相似文献
2.
GAO Rong WANG Xiaojing School of Mechanical Electronic Engineering Automation Shanghai University Shanghai China WANG Min No. Institute Shanghai Academy of Spaceflight Technology Shanghai China YU Maohua XIE Mingchun School of Mechanical Electronic Engineering Automation Shanghai University Shanghai China 《机械工程学报(英文版)》2007,20(3):75-78
The nonlinear dynamics of the lateral micro-resonator including the air damping effect is researched. The air damping force is varied periodically during the resonator oscillating, and the air damp coefficient can not be fixed as a constant. Therefore the linear dynamic analysis which used the constant air damping coefficient can not describe the actual dynamic characteristics of the mi-cro-resonator. The nonlinear dynamic model including the air damping force is established. On the base of Navier-Stokes equation and nonlinear dynamical equation, a coupled fluid-solid numerical simulation method is developed and demonstrates that damping force is a vital factor in micro-comb structures. Compared with existing experimental result, the nonlinear numerical value has quite good agreement with it. The differences of the amplitudes (peak) between the experimental data and the results by the linear model and the nonlinear model are 74.5% and 6% respectively. Nonlinear nu-merical value is more exact than linear value and the method can be applied in other mi-cro-electro-mechanical systeme (MEMS) structures to simulate the dynamic performance. 相似文献
3.
The cooling process of tanks relates to various physical actions, parts or components and fluids. A predication method is presented to evaluate the effects of cooling system for tanks . A predication model that includes the heat production, heat transfer and fluid flow modules is established. The engine combustion and friction between components act as the primary heat sources. The solid components of power transmission train are partitioned into thermal nodes. The heat conductions among the thermal nodes, coolant, lubricant, powerhouse fresh air, combustion gas and exhaust gas are taken into account. The coolant flow, lubricant flow and powerhouse air flow are also considered. The prediction model is resolved by use of a multilayer iterative technique and an arithmetic of local convergence combined with global convergence for coupled modules. A calculation example shows that the model can implement predication of cooling system under different environment temperatures and running conditions quite better. 相似文献
4.
5.
CHENG Kemei YAO Side YUAN Lihua 《核技术(英文版)》2007,18(5):272-275
Reaction of p-tert-oxocalix[4]arene in acetonitrile (CH3CN) by 308nm laser pulses was investigated to understand its mechanism as polymer stabilizer. Four main absorption bands were observed at 300nm, 400nm, 460nm and 540nm. The 300nm absorption was assigned to the absorption of phenoxy radical, and the 460nm and 540nm were triple state absorption. It was concluded that the relative stable phenoxy radical mediate was formed through intramolecular energy transition of carbonyl triplet after laser excitation in CH3CN. The formation mechanism of phenoxyl radical was quite different from that in cyclohexane (C6H12), which was cooperation of two-photon process and one-photon process. 相似文献
6.
References: 《核技术(英文版)》2007,18(2):86-87
The energy loss, produced by shielding effect of steel cage outside the source tube, is quite considerable. With PENELOPE software package, MC results have been obtained based on the simulation of different source con- formations. The result illustrates that the naked source tubes can improve the utilization ratio of the cobalt facilities. It demonstrates the applied value of the naked source tube in engineering. 相似文献
1