基于.NET访问AutoCAD数据库探讨

针对AutoCAD二次开发工具进行了研究和探讨,并对AutoCAD二次开发工具的历史发展做了综述.详细介绍了AutoCAD数据库的组织结构和AutoCAD.NET API对象模型的主要对象,并用一个例子分析了.NET访问AutoCAD数据库的开发步骤.     

定点绘制盘形凸轮轮廓曲线的程序开发

利用AutoCAD VBA向AutoCAD菜单栏添加新菜单项,创建图形用户界面,编制宏代码,并在AutoCAD中设计和定点绘制凸轮轮廓曲线,为在AutoCAD中设计和绘制复杂平面曲线提供了具体实例.     

AutoCAD定制探讨及应用实例

介绍了AutoCAD的定制,探究了AutoCAD程序文件、支持文件和图形文件的组织与结构,在此基础上探索在AutoCAD中创建自定义工具栏、工具选项板,并且制作幻灯片文件和幻灯片库文件的基本方法,并提供了AutoCAD的定制及二次开发的具体实例。     

使用AutoCAD快速准确绘图经验谈

AutoCAD软件是计算机辅助设计的重要工具,但对初学者并不易掌握,文章从如何提高绘图速度和如何准确绘图两个角度介绍了使用AutoCAD的有效方法,并分享了AutoCAD的学习和使用心得,希望对AutoCAD的学习者有所帮助。     

基于VB．NET二次开发AutoCAD的动态模拟

以参数化设计为指导思想,以Visual Basic.NET(VB.NET)为编程语言和开发工具,对AutoCAD软件进行二次开发,并给出实例.实例中借助AutoCAD强大的图形功能和VB.NET语言界面友好、功能强大的特点,建立了相应的数学模型,通过自动化界面技术控制AutoCAD应用程序对象来完成零件加工的简化动态模拟.对AutoCAD动态仿真功能进行了研究,并且为VB.NET语言对AutoCAD进行二次开发提供了借鉴.     

基于AutoLISP的AutoCAD二次开发研究

为提高AutoCAD软件的绘制效率和定向功能。采用Autolisp对AutoCAD软件进行二次开发,以实例介绍了应用Autolisp对AutoCAD进行二次开发的过程。软件系统可快速开发出各类零件的命令集,通过输入相应尺寸能实现零件的快速绘制。Autolisp开发工具能实现AutoCAD的定向开发,提高AutoCAD的绘图效率和准确性。     

AutoCAD二次开发的方法与实例

介绍了利用VBA对AutoCAD进行二次开发的技术基础,对基于Active X技术和应用面向对象方法开发AutoCAD的有关问题进行了分析研究,并以常用函数几何曲线的精确绘制为例,阐明了AutoCAD二次开发的基本思路、主要步骤和具体方法.     

AutoCAD与Word之间的通信技术

介绍了AutoCAD与Word之间的通信机制。基于OLE自动化技术 ,编写了一个能够在AutoCAD图形中与Word应用程序进行交互通信的程序 ,有效地实现了AutoCAD图形中的文本及Word文档中文本的共享和重用     

基于ObjectARX进行AutoCAD二次开发的研究

介绍了AutoCAD二次开发工具ObjectARX2004的功能特点、类库构成以及ObjectARX应用程序的框架结构,并以具体实例阐述了应用ObjectARX工具进行AutoCAD2004二次开发的过程,说明了学习和掌握ObjectARX对于AutoCAD二次开发具有重要意义。     

基于ObjectARX的AutoCAD二次开发及优化下料应用

板材下料是有效开展生产的一项必要活动,AutoCAD是进行下料排样的计算机绘图和设计的常用软件,同时AutoCAD为用户提供了非常开放的二次开发环境.为此,对作为AutoCAD 2007二次开发工具的ObjectARX 2007进行了探讨和研究,分析了基于ObjectARX的AutoCAD二次开发的程序开发流程,详细阐述了进行板料优化排样程序开发的关键技术以及进行AutoCAD二次开发的命令订制方法,然后实施了以ObjectARX 2007为基础、以Visual Studio 2005为开发平台、以遗传算法为主要优化算法的下料程序开发,在AutoCAD中开发出自动排样的优化下料应用程序.最后,通过排样实例验证了本方法的实用性.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...