摘要：To change the current phenomenon of ＂Being an armchair strategist＂ in the research of a stepping motor, the virtual simu- lation system of stepping motor was developed using virtual reality technique. The basic principle of stepping motor was expounded. The development strategy of the simulation software is introduced. Some key problems and their solutions, including coordinate transformation of rotor and order of on-off electricity for stator, were put forward in system development. Finally, there are three virtual simulation examples of the on-off electricity way in this paper. This work provides a valuable auxiliary tool for the study of the stepping motor.

摘要：In order to enhance the bearing capacity of non-circular gear pair, the non-circular gear pair with double generating angles is proposed based on the design idea of unsymmetrical gear with double pressure angles. The tooth profile is designed by generating cutting theory, the pure rolling mathematic model that the center line of unsymmetrical rack roll along non-circular pitch curve is built, the digital model of non-circular gear with double generating angles is created through the second development method of CAD software, and then the drive characteristic and tooth strength are analyzed. The results show that the design method for double generating angles non-circular gear proposed in this paper is feasible, which is significant to improve the bearing capacity of non-circular gear pair.

摘要：为了满足齿轮传动系统低噪声、小振动和高传动精度等要求,提出了一种基于传动误差峰峰值最小化的齿轮拓扑修形优化方法。基于直线与抛物线的复合修形叠加曲线,在标准渐开线齿轮的齿廓和齿向方向对齿轮进行修形设计,提出一种拓扑修形齿面形成方法;以齿轮传动误差峰峰值最小为优化目标,基于遗传算法对提出的拓扑修形齿轮齿面进行参数优化,得出拓扑修形齿轮齿面的最佳修形参数;将拓扑修形齿轮和标准齿轮进行对比,分析修形前后齿轮的齿面受载情况和齿根应力分布情况,验证了提出的拓扑修形优化方法的有效性。

摘要：龙、凤形象自古是中国传统艺术形象,在陵墓随葬品中作为通天地的工具,既是权力、地位的象征,又是死后幻想升天的助手。战国以来,逐渐形成由青龙、白虎、朱雀、玄武构成的“四灵”,后来麒麟加入其中,也称为“五灵”。天禄、辟邪是以外来的狮子作为依托,在南北朝时期逐渐成为陵墓神兽主题。中国传统的龙、凤、“四灵”,加上外来影响诞生的域外珍奇,如翁仲、麒麟、天禄、辟邪、大象、鸵鸟、骆驼等题材,通过“翼化”、夸张等艺术手法的表现,共同构建了中国陵墓神兽这一纪念艺术类型的发展图景。这些陵墓神兽体积庞大、凝重厚硕,立于天地之间,成为古往今来、现世与往生之间的联系和承载,因此,他们的造型必须夸张、蓄势待发,时刻准备凌逾事物表象,达到咫尺万里之势。

摘要：In this paper, modal analysis theory, equivalent dynamic model of the joint surface of assembly and identification methods of joint surface parameters are the main theories. Static and modal analysis of the working table components of the FM6324 machining center is done. The three-dimensional model of the working table components is established using Pro E at first, then static characteristics is obtained through ANSYS contact analysis; finally, the dynamic model is established in ANSYS, and its dynamic characteristics is obtained through ANSYS modal analysis.

摘要：近三十年来,经过几代学人的不懈努力,对吴哥古迹的研究逐步开展,特别是对吴哥王朝的历史、建筑、雕塑艺术的研究取得了一定的成果。但相对国外对吴哥古迹的研究,国内还相当薄弱,特别是对吴哥雕塑艺术的专题研究成果就更少了,多角度、多方位专题研究吴哥雕塑艺术的专著,尚属空白。

摘要：针对农作物育种处理数据方式落后的现状,设计并实现了基于.NET的农作物育种助手软件。系统基于.NET平台进行设计,采用MVC模式进行实现,在数据采集端利用手持设备进行采集,数据通过移动网络实时传输到服务器处理,或者通过手持设备暂时保存数据,采集完成后同步到服务器中。系统的运用能显著提高农作物育种效率和育种质量,使数据处理变得方便、快捷。

摘要：针对阀控液压缸节流损失大,电机械执行器带载能力弱的问题,通过液压缸活塞与电机械执行器螺母刚性连接的方式,将两类执行器集成为新型的机电液混合驱动直线执行器,主要由电机械驱动机构和液压驱动机构组成。电机械驱动机构用于执行器运动控制,液压驱动机构具有功率放大功能,用于提高执行器带载能力。研究中,活塞杆设计为中空结构用于长行程丝杠的安装,活塞上增设有通油孔用于油液的快速流通。通过密封设计,将活塞两侧设计为可充高压油液的容腔,采用ANSYS Workbench有限元软件对新型执行器零部件进行强度校核。最后,制造执行器试验样机并构建性能测试平台,测试结果表明,设计的机电液混合驱动直线执行器密封效果良好,运动过程中启制动平稳,具有良好的速度与位置控制特性;执行器液压驱动机构增力效果显著,且节流损失较小。所提机电液混合驱动直线执行器融合了液压驱动和电机械驱动的优点,为实现高能效高功率密度直线驱动提供了一种新的思路。

摘要：A 2MeV thermionic cathode test stand was established to meet the requirement of the large area thermionic cathode system.A 100ram in diameter type'B'thermionic dispenser cathode was developed.A 1000A emission current was produced at the voltage of the diode about 1.8MV,the pulse width about 90ns(FWHM),and the cathode temperature about 1350℃.The emission current density is 12A/cm^*** results indicate that a large area thermionic cathode which produces high quality and high current electron beams is *** results also indicate that the ability of cathode emission relies on the diode-vacuum and cathode-temperature.

摘要：研究了一种低成本、高效率的BGA全自动植球机,该植球机通过计算机控制,一次性将所需的锡球拾取、摆放到BGA基板上,并能对植球情况进行图像检测。文中着重介绍了STAR-04Z全自动植球机的总体设计方案,研究了真空吸引法植球技术的原理和BGA全自动植球机的系统组成,并进行了原理样机的结构设计,提出了一种基于BGA全自动植球机图像检测和精确定位系统的体系结构。