快速实现AutoCAD三视图宽相等的开发方法

在AutoCAD2004环境下,利用ARX开发工具,根据我国绘制机件三视图的制图标准,开发了一个快速实现三视图中俯、左视图宽相等的ARX应用程序。论述了程序的实现方法,以及程序实现过程中的一些关键技术,如图中实体最大、最小X、Y坐标值的获取方法、辅助线图层的生成方法等。利用该程序,用户只要拾取俯视图或左视图中的一点,程序就可以快速找到它在左视图或俯视图中对应的宽度位置,并自动画出辅助线。该程序已用于某机械CAD中,大大提高了设计和绘图的效率。     

巧用AutoCAD在三投影面体系中绘制立体的三视图

主要阐述了在制作机械制图课件过程中,运用AutoCAD绘图软件绘制三个投影面、立体以及立体在三个投影面上的投影——主视图、俯视图、左视图,让三个视图与立体图保持投影对应关系.     

VB在AutoCAD中的初步应用

本文简要地讨论了 VB编程语言在 Auto CAD中插入图块 ,建立视图 ,参数作图 ,标准件生成 ,明细栏制作以及曲线绘制等方面的初步应用。     

可在微机上实现油路块CAD的软件

Auto CAD 是一种专门用于绘图的系统软件。它的绘图功能强大、简单易学、使用方便。俗话说图纸是工业的语言,然而,在工程制图上我国始终处于手工绘制的落后状态。为了早日改变这种状况,实现设计、制图自动化,对Auto CAD 应用的研究有着     

AutoCAD高效绘图与出图技巧

针对目前使用Auto CAD绘制机械图样过程中出现的各种不遵守国家标准或遵守标准但出图结果不符合制图要求的现象,依据不断的设计实践和教学经验,提出高效合理绘制图样并出图的操作技巧。通过Auto CAD的机械基础环境设置、样图创建、按实际尺寸绘图等基础操作完成国家标准的贯彻,再通过sacle缩放、尺寸标注、出图设置三者的比例协调控制,达到绘图与出图的一致性,大大提高了绘图效率和出图的正确率。     

微机辅助绘图软件的开发和应用

本文运用Auto CAD绘图软件的长菜单功能,以Auto LISP语言编写程序,开发出变压器及叉指形散热器两个绘图软件包。可用点菜方式在屏幕上查询上述两种产品,绘出工作图,并可用输入参数方式开发系列产品。     

巧用Auto CAD绘制三视图

提出了用Auto CAD快速，准确绘制三视图，保证三视图之间投影规律的几种方法，并有例子详细介绍了这几种方法的操作过程。     

AutoCAD环境中立体图转化为三视图的方法研究

介绍了在AutoCAD绘图环境下,由三维立体模型生成基本二维三视图的方法。结合具体实例,探讨了用AutoCAD2008中的flatshot命令制作二维视图的步骤和方法。应用该方法可大大减少绘制二维视图的工作量,提高绘图效率,具有一定的工程应用价值。     

AutoCAD中从3D模型绘制2D图形的技术

阐述了在使用 Auto CAD进行机械图样绘制时直接作三视图的不便之处。介绍了一种在 Auto CAD中通过实体建模直接生成机械图样的新方法及其命令和技巧。     

尺寸公差自动查询及标注系统的设计

运用VBA语言开发出一套用于Auto CAD环境下公差自动查询与标注软件,它以良好的人机交互界面让用户方便地一次完成查找尺寸公差和标注尺寸公差两项工作,有效地提高了绘图效率,在工程绘图中具有较大的实用价值.     

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...     

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。     

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。     

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.     

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。     

基于多目标非支配解提取法的电力系统无功优化

针对传统的电力系统多目标粒子群优化算法采用权重系数法将多目标转化为单目标,从而忽视了各目标函数间的竞争关系这一问题,提出将非支配解提取法运用到电力系统多目标无功优化中,并设定了一套提取规则,以电力系统中的有功网损、电压偏差和电压稳定裕度为目标,使目标在充分竞争的情况下得出Pareto最优解,利用IEEE-14节点系统对多目标非支配解提取法的电力系统无功优化进行了仿真测试。研究结果表明,该算法一次运行可以得出多组非支配解,既有偏向单个目标的解也有兼顾所有目标的解,克服了权重系数法的盲目性和单一性,可使电力决策者根据实际问题选择最优解,具有较好的灵活性与多样性。     

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.     

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.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.