基于DSP的CANopen通讯协议的实现

CANopen是一种开放的应用层协议,其应用可以进一步提高系统的可靠性、通讯效率及灵活性,而且可以使产品具有很好的兼容性。本文采用CANopen通讯协议实现了CAN总线DSP系统与上位机CAN卡之间的通讯,并通过测试实验验证了信息传递的可靠性,保证了全数字网络化伺服驱动系统中对电机控制的准确性和实时性。

CIMS设计过程中存在的一些问题及解决方案

提出了一种新的集成的I2 DEF方法 ,并介绍了与之配套的设计开发工具 ,用以支持大型复杂信息系统的设计与开发 ,它可以成功地解决计算机集成制造系统设计开发过程中遇到的许多问题。本文指出了我国CIMS工程存在的问题 ,分析了这些问题产生的原因 ,并结合企业实际给出了应用I2 DEF方法的解决方案。

面向CIMS的多数据源互操作与开放分布处理系统———CIMS-MIODP的设计与实现

多数据源互操作与开放分布处理系统ＣＩＭＳ－ＭＩＯＤＰ是采用分布对象互操作与代理技术，实现面向ＣＩＭＳ的基于ＲＰＣ的远程对象访问ＲＯＡ（ＲｅｍｏｔｅＯｂｊｅｃｔＡｃｅｓ）功能和基于ＳＱＬ３的远程数据库访问ＲＤＡ（ＲｅｍｏｔＤａｔａｂａｓｅＡｃｅｓ）功能的系统，为ＣＩＭＳ环境下的信息集成与分布处理提供了不同层次的支持功能。本文讨论了ＣＩＭＳ－ＭＩＯＤＰ系统的主要设计和实现问题，包括基本模型、扩展服务和协议、对ＳＱＬ３的支持、系统实现结构等。

对象互操作的行为模型

对象互操作表达了一组对象在完成某一任务时的动态协作关系，对象互操作的行为描述与抽象是支持面向应用对象互操作的基础．对此，提出一种活动模型作为描述对象互操作行为的方法．该方法以一阶时态逻辑为基础，表达了互操作对象之间交换消息的时态顺序和不同活动之间的行为关系．在该方法中，提出了活动特化和活动聚合两种行为抽象机制，实现了对象互操作行为的复用．最后讨论了给定论域的类模式和活动模式的一致性集成问题。

公路电子收费系统中DSRC协议规范的应用设计

根据领域中专用短程通信()协议的基础规范,设计出应用于电子收费系统的物理层、数据链路层和应用层相关参数ITSDSRCDSRC选定和设置。力求在电子收费领域相关的装置与设备能遵循指定的规格标准,并增进各系统相互之间的相容性和互连性。

岩石类材料静态、动态拉伸弹性模量测试方法研究——以巴西圆盘试验和霍普金森压杆、效应为手段

As we all know, rock-like materials will absolutely show very different mechanical properties under the compressive stress and tensile stress respectively. Similarly, under the dynamic compressive stress or dynamic tensile stress, the characteristics of the dynamics showed by the rock-like materials also have great differences from the mechanical behavior under static force. Studying their similarities and differences in rock mechanics theory and practical engineering will be of great significance. Generally, there are compression modulus of elasticity and tensile modulus of elasticity corresponding to compressive stress state and the tensile stress state in the rock. Both the two kinds of elastic modulus play an extremely important role in calculation of engineering mechanics. Their reliability directly affects the accuracy and reliability of the calculation results of internal stress field and displacement field of engineering rock mass. At present, it is easy to obtain the compression modulus of elasticity in laboratory; but it is very difficult to determine the tensile modulus of elasticity with direct tensile test due to that direct tensile test is difficult to perform in laboratory in general. In order to solve this problem, this thesis invents and develops several indirect test methods to determine the static or dynamic tensile modulus of elasticity of rock-type materials with high reliability and good interoperability. For the static tensile modulus of elasticity, the analytical stress field solution has been given out for the Brazilian disc under the radial and linear concentration load with Airy stress function method. At the same time, the stress field has been modeled for the Brazilian disc test by using the finite element software of ANSYS and ADINA. The analytical stress field solution is verified to be right by comparatively researching the analytical stress field solution and the numerical stress field solution. Based on the analytical stress field solution, this thesis proposes that a strain gauge is pasted at the Brazilian disc center along the direction perpendicular to the applied force to indirectly determine the static tensile modulus of elasticity, and related measurement theory also has been developed. The method proposed here has good feasibility and high accuracy verified by the experimental results. For the dynamic tensile modulus of elasticity, two measuring methods and theories are invented here. The first one is that the Split Hopkinson Pressure Bar is used to attract the Brazilian disc to generate the dynamic load, make the dynamic tensile stress is formed at the Brazilian disc center; and also a strain gauge is pasted at the Brazilian disc center to record the deformation. The second is that, in the Hopkinson effect phenomenon, the reflection tensile stress wave is formed when the shock wave propagates to the free end of cylindrical rock bar and reflect, which can make the rock bar is under dynamic tensile stress state; and some strain gauges are pasted at the appropriate place on the rock bar to record the strain coursed by the tensile or compressive stress wave. At last, the dynamic tensile modulus of elasticity can be determined by the recorded strain and the dynamic tensile stress which can be determined by related theories developed in this thesis.