计算机设计软件NX6.0实战篇

本人在2014年第2期《信息技术与信息化》发表过一篇《计算机设计软件NX6.0几种复合建模方法》中谈到NX软件复合(混合)建模法主要有径面法,中面法,正交法几种,本文以一个典型实际例子向大家展示一下NX经典径面建模法的技巧,与大家分享NX复合建模的乐趣。     

基于NX CAD/CAM技术在复杂零件加工中的应用——以“数控程序员认证项目”中的题库为例

以项目中的复杂零件为例,论述了NX CAD/CAM模块在实际加工中的应用过程和方法,通过UG CAD模块对零件进行实体建模设计;使用UG CAM模块对零件进行合理的加工参数设置,产生刀具轨迹,完成零件的数控加工。NX软件能在复杂零件的数控加工发挥优势,提高加工效率,保证产品质量。     

基于X3D的机械基础虚拟实验室的设计与实现

传统机械基础实验室存在场地不足、设备老化短缺、可扩展性差等问题.本文研究了使用UG NX软件建模、输出为VRML格式、建立模型运动仿真的方法,同时结合X3D和X3DOM技术,在网页中构建了机械基础虚拟实验室,为机械基础实验教学提供了新的手段和思路.     

基于激光熔覆的镍基复合涂层制备方法与性能研究

提出一种在轴类零件表面，通过激光熔覆技术制备颗粒增强的Ti/B₄C/dr40复合涂层的方法。研究和分析复合涂层中陶瓷颗粒的生成机制以及对晶粒的细化作用，柱状晶向等轴晶的转变过程，涂层表面裂纹产生的原因以及温度梯度和凝固速率对涂层显微组织的影响规律。为分析涂层的机械性能，对涂层进行硬度、压痕和划痕试验。结果表明，复合涂层与基体具有良好的冶金结合性能，凝固过程中生成的TiC和TiB₂硬质颗粒在磨损过程中起到骨架支撑作用，抑制基体的变形，降低材料去除率，提高了涂层的硬度和抗磨损性能。研究表明，通过激光熔覆技术制备的镍基复合涂层可以实现轴类零件的表面强化和再制造，具有良好的应用前景。     

三星单电新成员NX-5

韩国三星公司在于6月4日发布消息．针对零售市场发布了旗下可换镜头电子取景器（EVIL）相机NX系列新品NX5。NX5计划于今年6月上市．目前的官方报价是699欧元,约合5850人民币。NX5是稍早前发布的三星NX10的简化版．NX5与NX10几乎完全一致的软硬件配置．简化的硬件主要是LCD屏的性能．NX10为3英寸61．4万像素AMOLED显示屏．NX5则为3英寸23万像素。     

Mentor Graphics发布无缝集成的同步CFD仿真工具FIoEFD

Mentor Graphics公司（NASDAQ：MENT）近期发布了最新同步流体力学（CFD）仿真工具FloEFDfor Siemens NX,它无缝集成在Siemens NX产品生命周期管理（PLM）软件。不同于其他基于NX的工具,明导公司的FloEFD for Siemens NX软件直接使用原始NX模型。     

轴类零件数控车削加工工艺探究

随着世界经济与科技技术的高速发展,机械制造产业的发展也愈发迅猛,而其中数控技术也得到了很大的提高,为机械零件的生产带来了许多的便利。对于实际中工件生产加工而言,数控技术的广泛运用,有效地促进了生产的加工效率,同时也带来了很大的经济效益。本文首先介绍了数控车削加工工艺在目前的应用,然后着重对轴类零件的数控车削加工工艺的方案进行了分析,最后是关于轴类零件数控车削加工工艺的难点探究。     

Mentor Graphics发布无缝集成的同步CFD仿真工具FloEFD

Mentor Graphics公司(NASDAQ:MENT)近期发布了最新同步流体力学(CFD)仿真工具FloEFDfor Siemens NX,它无缝集成在Siemens NX产品生命周期管理(PLM)软件。不同于其他基于NX的工具,明导公司的FloEFD for Siemens NX软件直接使用原始NX模型。FloEFD使用有限体积的数学技术,支持广泛的应     

数控轴类零件加工工艺设计

随着数控技术的日益成熟,数控技术的应用领域也在不断的扩大。本文以数控轴类零件为研究对象,对其进行了工艺方案的分析,工装方案的确定,刀具和切削用量的选择。通过分析可知,该数控轴类零件的加工工艺整体设计具有可行性,能够完全满足精度、效率和工序要求。     

支持MFC的NX二次开发向导研究

在分析了NX二次开发向导和VC设计向导的功能及构成的基础上,通过嫁接方法建立了支持MFC的NX二次开发向导,并给出了具体建立步骤.建立的支持MFC的NX二次开发向导方便了NX二次开发,使在开发中可以充分利用MFC的强大功能.通过该方法可以统一企业中二次开发的标准化.     

类果蝇复眼视觉神经计算建模及仿生应用研究综述

随着类果蝇复眼视觉神经计算建模技术的快速发展,如何提高运动目标的实时检测追踪等仿生应用能力成为类果蝇复眼视觉神经领域的研究难题,所以研究类果蝇复眼视觉神经计算建模及其仿生应用具有非常重要的意义。类果蝇复眼视觉神经系统是一个高度平行的专用视觉神经网络模型,并具有适度的复杂性以允许快速进行视觉信息处理。本文首先从类果蝇复眼的生理结构、感光细胞的光电转换、视叶神经的加工处理、中央脑的认知抉择4个部分详细阐述类果蝇复眼视觉神经计算建模的研究现状,然后介绍类果蝇复眼视觉神经计算建模在军事与民用领域的典型仿生应用,最后展望了类果蝇复眼视觉神经计算建模的发展趋势与挑战。     

基于业务感知投影的高铁线路评估方法研究与实践

本文依靠大数据分析手段,运用高铁用户业务感知建模,构建多维数据感知评估算法对高铁路段感知投影,实现高铁线路感知评估；发现问题路段后采用遍历巡更算法,对问题点智能分析定位。通过基于高铁用户感知投影的高铁线路评估与高铁问题路段智能分析定位,实现了一种面向高铁用户群的大数据评估分析方法。     

Facial parts swapping with generative adversarial networks

In this paper, we present a novel deep generative facial parts swapping method: parts-swapping generative adversarial network (PSGAN). PSGAN independently handles facial parts, such as eyes (left eye and right eye), nose, mouth and jaw, which achieves facial parts swapping by replacing the target facial parts with source facial parts and reconstructing the entire face image with these parts. By separately modeling the facial parts in the form of region inpainting, the proposed method can successfully achieve highly photorealistic face swapping results, enabling users to freely manipulate facial parts. In addition, the proposed method is able to perform jaw editing based on sketch guidance information. Experimental results on the CelebA dataset suggest that our method achieves superior performance for facial parts swapping and provides higher user control flexibility.     

低损耗大有效面积光纤在新一代海缆系统中的应用

本文结合近年来国际海底光缆系统的发展情况,阐明了N×100 Gbit/s DWDM海缆系统对光纤的技术要求,说明了低损耗、大有效面积光纤在新一代海缆系统的应用及其发展前景。     

利用弹头目标微动信息的两种三维散射中心提取方法

雷达目标三维散射中心提取技术广泛应用于散射特性分析、建模以及目标跟踪.结合弹头目标的微动信息,可以间接得到雷达视角信息.本文在分析了此转化关系的基础上,提出两种三维散射中心提取方法,分别是投影方程求解法和球面拟合法.原理上,分别从代数和几何两个方向体现一维投影距离到三维空间位置的映射原理;算法上,解方程法是基于映射原理,进而求解矩阵方程来实现的;球面拟合法根据一维投影数据的球形分布规律从映射图中提取球面,过原点的直径与球面的交点即为强散射中心.GTD散射模型回波数据和暗室测量数据分别验证了这两种方法的有效性.最后,对两种方法的特点和性能进行了比较,同信噪比下,球面拟合法优于解方程法约15dB.     

CATIA标准零件库的开发

针对CATIA 标准零件库更新性差、种类少、无法应对企业进行针对性使用的缺点，研究了CATIA标准零件库的二次开发。文中主要以CATIAV5R18作为支撑平台，利用SQL Server 2005存储和管理标准件信息，通过VB.NET对CATIA二次开发，并且做出整个系统的主界面。根据企业对机械零件的不同要求，在主界面中选择不同的参数，并将从数据库中搜索到的零件调用到CATIA中进行编辑和装配。结果表明，该管理系统针对性强、避免了重复建模，减少了设计时间、提高了设计效率。     

Statistical Analysis of High-Resolution SAR Ground Clutter Data

This paper deals with the problem of modeling high-resolution synthetic aperture radar clutter data from different vegetated areas. We analyzed moving and stationary target recognition (MSTAR) data sets focusing on histograms, moments, and covariance of clutter amplitude, texture, and speckle. The most celebrated statistical models are tested on real data of grass field or wood and trees to validate the goodness of fit of the compound Gaussian model in different scenarios. The results demonstrate that for grass fields, the compound Gaussian model provides a good data fitting. This is not the case for woods images where the speckle is not more Gaussian distributed. Covariance analysis and concluding remarks complete this paper     

Modeling projection printing of positive photoresists

The accompanying papers "Optical Lithography" and "Characterization of Positive Photoresist" introduce the concepts of modeling using destruction of the photoactive inhibitor compound to describe exposure and a surface-limited removal rate to describe development together with the optical exposure parameters A, B, and C and a rate relationship, R(M), which characterize the photoresist for modeling purposes. This paper applies the model to, the projection exposure environment: exposure and development of photoresist are treated with a simulation model that allows computation of image surface profiles for positive photoresist exposed with a diffraction limited real image.     

Packaging Effect on MEMS Pressure Sensor Performance

In this study, the effect of epoxy based molding compound packaging on a micro-electro-mechanical system (MEMS) pressure sensor performance is investigated. A series of experiments were conducted to characterize the MEMS sensor over temperature and pressure changes by measuring output voltage signals. The sensor was modeled by a finite element method to investigate the stress developments. The molding compound was assumed as elastic and viscoelastic material to examine the material modeling effect on the calculation results. The model was verified by comparing the calculated results with experimental data. It was found that the stress induced by the molding compound had significant influence on the sensor performance, and the accuracy of the calculations was highly dependent on the modeling of the molding compound. Based on the results, the mechanism of the stress development and its effect on the sensor signal were discussed     

Synthesis of antenna patterns with prescribed nulls

The least mean square pattern synthesis method is extended to include constraints such as pattern nulls or pattern-derivative nulls at a given set of angles. The problem is formulated as a constrained approximation problem which is solved exactly, and a clear geometrical interpretation of the solution in a multidimensional vector space is given. The relation of the present method to those of constrained gain maximization and signal-to-noise ratio (SNR) maximization is discussed and conditions for their equivalence stated. For a linear uniformN-element array it is shown that, whenMsingle nulls are imposed on a given "quiescent" pattern, the optimum solution for the constrained pattern is the initial pattern and a set ofM-weighted(sin Nx)/sin x-beams. Each beam is centered exactly at the corresponding pattern null, irrespective of its relative location. For the case of higher order nulls, thenth pattern derivative is similarly canceled by thenth derivative of a(sin Nx)/sin x-beam. In addition, simple quantitative expressions are derived for the pattern change and gain cost associated with the forced pattern nulls. Several illustrative examples are included.