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71.
Ping Yang Fuyun Liu Yong Liu Ningbo Liao Binghao Bao 《Structural and Multidisciplinary Optimization》2008,35(5):489-498
Electronic equipment’s system is always manufactured as a superprecision system. However, it will be used in harsh environment.
For example, the computer in moving vehicles will be acted by vibrations. The objective of this paper is to provide a systematic
investigation to test and computer-aided design of the vibration isolator for protection of electronic equipment’s system
in harsh vibration environment. A micro-oil damping vibration isolator is designed and manufactured through coupling the oil
and spring by ingenious tactics. The structure of the oil damping vibration isolator can achieve circulating oil damping function
with an inner tube and an outer tube (some orifices are manufactured on upside and underside of the inner tube). The dynamics
of the key model machine is systematically investigated. Based on the test, a nonlinear dynamic model for the vibration isolator
is presented by analyzing the internal fluid dynamic phenomenon with respect to the vibration isolator. The model considers
all the physical parameters of the structure. Comparisons with experimental data confirm the validity of the model. In the
other, the model is integrated by introducing normalization measure. The normalization model shows the actual physical characteristics
of the oil damping vibration isolator by considering quadratic damping, viscous damping, Coulomb damping, and nonlinear spring
forces. An approximate solution is deduced by introducing harmonic transform method and Fourier transform method. Therefore,
a parameter-matching optimal model for computer-aided design of the vibration isolator is build based on approximate solution.
An example confirms the validity of the computer-aided design integration.
相似文献
Ping YangEmail: |
72.
This paper presents two posture risk quantification methods: first, an event-based method where the most common and the worst postures are estimated in a task; second, a time-based method where posture distributions are calculated from random samples of observed postures in the task. A 'click-on-screen' posture data entry method was developed for the time-based posture analysis method to make the observation process easier and to reduce possible posture categorization bias. Both methods were used to quantify various work posture parameters among a study cohort of 733 subjects from a prospective epidemiological study of upper extremity musculoskeletal disorders. Composite posture indices using a modified Rapid Upper Limb Assessment (RULA) method were also computed using data obtained by the two posture analysis methods. Results showed that both methods were able to distinguish jobs with large differences in certain posture measures. However, they did not produce the same results and could not be used interchangeably. Risk evaluation criteria should be developed, either for specific posture parameters or as a composite index, with a well-defined postural analysis method, so that users can follow exact procedures and obtain comparable results. The event-based method is easy to use and may suit practitioners better, while the time-based method adds more information to the measurement and may suit users who want more detailed information about posture exposure. 相似文献
73.
网络计费系统的主要技术及ASP实现——LAN用户基于IP流量上网计费 总被引:3,自引:0,他引:3
介绍了开放实验室实现网络计费的背景和网络计费的解决方案,着重介绍了网络计费软件的主要组成部分及其关键技术,并探讨了开发针对局域网用户帐户按照IP流量进行上网计费系统的有关问题。 相似文献
74.
一种检测绝缘纸板微水分的电容式传感器 总被引:1,自引:0,他引:1
开发一种用于检测变压器绝缘纸板微水分的电容式传感器 ,该传感器通过感应绝缘纸板的介电常数在其干燥过程中的变化而用于在线实时检测。它灵敏度高、温度漂移小、便于安装和信号传送 ,其输出信号经处理后 ,可由微机处理并显示水的质数分数。介绍了传感器的工作原理、结构形式及相关系统。 相似文献
75.
76.
供应链集成化模型与优化 总被引:2,自引:0,他引:2
本文建立了一个包括供应商、制造商、销售商
在内的集成化模型,这一模型含有线性状态方程和神经网络非线性模型,提出了库存成本、
供应成本、生产水平等在内的供应链目标函数和约束条件.对于供应链集成化模型采用模拟
退火方法进行优化,并以辽化公司为背景进行了初步条件的仿真工作. 相似文献
77.
A method for observing the three-dimensional morphologies of inclusions by deeply eroding a steel sample with a kind of organic solution composed of bromine water,acetone,and HC1 (volume ratio,45∶45∶10... 相似文献
78.
Process operability can be defined as the ability of a process to reject disturbances at a specified operating point and/or to move quickly and smoothly from one operating point to another operating point using a feedback control system. Unlike linear processes, the properties of nonlinear processes (e.g., stability, minimum phase condition, etc.) are different around different equilibria. Most existing operability analysis for nonlinear systems focuses on one particular operating point of interest. This paper addresses the issues of dynamic process operability at various operating points, including the reachability of all equilibrium points or output trajectories in an operating region, regardless of initial conditions. In this work, a nonlinear analysis approach is developed based on the concept of incremental stability. Conditions for incremental stability are derived based on incremental dissipativity. The links between input and output multiplicities and incremental dissipativity are explored. The dynamic control performance achievable in terms of the speed of the response of the closed-loop system and offset minimization is studied. A method for determination of incremental dissipativity using Linear Differential Inclusion (LDI) is also presented, to facilitate the dissipativity based operability analysis. 相似文献
79.
针对装车台系统与生产系统之间的信息孤立问题,设计了一套数据交互系统。该数据交互系统利用OPC技术和C#语言进行开发,通过ADO.NET远程连接数据库,对装车台系统中的数据进行相应的读写操作,并利用OPC接口实现对生产系统中的数据进行操作。该数据交互系统自投用以来,使得原本独立的两个系统之间能够进行数据传输,实现了在控制生产系统中对装车台系统相关数据的监控,有效地解决了企业数据交互上存在的问题,对提高企业安全生产水平有重大意义。 相似文献
80.