SMT优化系统的设计与实现

基于SMT系统优化的旅行商问题（TSP）进行了分析和研究,对SMT系统优化进行了系统分析设计,介绍了如何减少X-Y工作台运动,提出两种针对环球HSP贴片机最优路径的优化算法,并基于一种方法编程实现了基本方案。最后在HSP贴片系统上使用本解决方案,大幅度提高了生产效率,证明了本解决方案的优越性和高效性,同时也为用其它算法...     

芒特艾萨矿业公司希尔顿铅锌选矿厂的新工艺和新设备

澳大利亚芒特艾萨矿业有限公司,是世界上铜、银、铅、锌的主要生产基地之一。本文详细介绍了该公司新建的希尔顿选矿厂的生产和所采用的新工艺和新设备。     

地球物理勘探联合反演在六盘山盆地的应用

在六盘山盆地进行重力、电法和地震综合勘探的基础上,应用地球物理联合反演方法研究和解决盆山接触关系、断层分布、深部目的层分布和有利构造圈闭特征等问题,为油气勘探部署提供科学依据。     

THE UNSOLVED MESSAGES OF PEARL HARBOR

In 1941, the United States Navy intercepted enough Japanese naval messages to predict the attack on Pearl Harbor if the code which protected them had been solved. The messages would have disclosed that, while the Japanese government cynically conducted diplomatic negotiations with the United States, the Japanese Combined Fleet under Admiral Isoroku Yamamoto, beginning as early as September 1941, systematically prepared ships, crews, weapons, tactics, and a complicated fuel supply system for the most ambitious operation ever undertaken by the Japanese navy. Details of Japan's intentions were hidden from Navy cryptanalysts because of limited manpower resources and because all Japanese navy codes were assigned a lower priority than Japanese diplomatic codes and German submarine threat.     

贴装元件的方差环形投影特征匹配识别

为了准确定位贴片后印刷电路板（PCB）上电子元件的位置,提出了一种基于方差环形投影的图像快速匹配算法。先将输入图像用小波变换分解为不同尺度的低频图像,之后利用方差环形投影特征做序贯相似性检测得到一系列可能的匹配点,最后在这些点上作相关匹配运算,获得其准确的位置。实验证明该算法大大减少了计算量又保持了匹配的精度,而且对图像的旋转不敏感。     

我国绿洲地区城乡空间组织模式-以新疆玛纳斯县为例

绿洲是荒漠地区的精华地段,也是重要的生态功能区、农牧业区和城乡人口集聚区,因此探索建立符合绿洲自身特征的城乡空间组织模式,对于推进绿洲地区的健康、可持续发展显得尤为重要和紧迫。研究以新疆玛纳斯县为例,分析了天山北麓绿洲地区城乡关系的特殊性,基于该地区的绿洲生态本底条件,提出了4种符合绿洲地区的城乡空间组织模式：城镇集聚模式、农业引导统筹模式、牧业引导统筹模式和生态保护模式,以期为绿洲地区新型城镇化理论研究提供支持。     

Sliding mode control of a shear-mode type ER engine mount

This paper presents feedback control characteristics of a shear-mode type electro-rheological (ER) engine mount. The field-dependent yield stress of an arabic gum-based ER fluid is obtained using a couette type electroviscometer, and it is incorporated into the governing equation of motion of the ER engine mount, which is derived from a bond graph model. A sliding mode controller which directly represents the field-dependent damping force is formulated by taking into account the stiffness and damping properties of the systems as parameter uncertainties. The controller is then experimentally realized by imposing a semi-active actuating condition. The effectiveness of the proposed ER engine mount is demonstrated showing capabilities of isolating the vibrations due to sinusoidal and random excitations.     

高密度组装电气互联新技术原理与研究方法

网络通信技术的高速发展围绕着小、轻、高速和高密度几个方向给IT市场提出了多样化的需求。介绍了高密度组装发展的现状和未来的发展趋势。CSP的研制使组装密度和性能得到提高，达到二维组装密度的极限；三维多芯片组装使组装密度达到一个新的高度，高速性能大大提高，同时力求降低制造成本。21世纪互联技术将继续沿着高密度和高速性方向发展。     

黄山鲁森林公园白水湖景区及山顶景观工程规划

黄山鲁森林公园位于南沙区的中心城区（小南沙）内,是南沙区中心城区的生态绿色核心,是都市中珍贵的绿色资源。整个公园占地约1200多公顷,主峰海拔295 m是广州南部地区的最高峰,是广州地区最大的开放式森林公园。     

Placement sequence identification using artificial neural networks in surface mount PCB assembly

The widespread use of automation in the printed circuit board (PCB) assembly domain has been dictated by the increasing density of components on PCBs coupled with the continual decrease in component lead pitch, greater product mix, smaller volumes, quality considerations, and the increased cost of labour. However, these advances in technology have also resulted in automated systems that are complex, and solving problems related to these systems requires the efficient use of extensive specialised knowledge.Expert (or knowledge-based) systems have become a widely accepted problem solving methodology for the surface mount PCB assembly domain. Nevertheless, problems in the PCB assembly domains are frequently unstructured, ill-defined, and difficult to communicate. Artificial neural networks provide a novel approach and an advanced technology to deal with the weaknesses and problems associated with expert systems.The surface mount component (SMC) placement process plays a vital and influential part in determining the throughput time of a PCB assembly line. It is important to identify an efficient component placement sequence while considering constraints such as feeder location and tooling and nozzle optimisation. This research studied the use of artificial neural networks as a complement to expert systems in PCB assembly. A prototype decision support system that combined the use of artificial neural networks and expert system techniques to identify a near optimal solution for the surface mount placement sequence problem was designed, implemented, and validated. Artificial intelligence based technologies such as expert systems and artificial neural networks were used in a mutually supportive manner to solve a complex problem within the surface mount PCB assembly domain.