识别民机产业发展特点 提高民用航空产品研发水平

就基本的管理规律和参数而言,所有航空产品的研制基本一致,但因为市场和客户的不同,民用航空产品研制在体系建设和技术覆盖面方面有自己的特点,尤其是适航规章要求和客户使用环境不同,使得民用航空产品的研制必须要更多地把产品全寿命周期的技术成功和运行支持纳入早期的研制活动,这必然带来在研制体系和技术能力建设方面的差异化,而早日识别和把握这些差别是民用航空产品产业健康发展的必须。     

月球车的视觉和自主导航系统

基于当前对于月球车、火星登陆机器人等的研究结果，介绍了月球车的视觉系统、控制方案和路径规划方法，并提出了对于月球车的控制方案的见解和路径规划的一些方法。     

一种修正表面温度计误差的分度方法

介绍了一种修正表面温度计误差的分度方法，该方法包括模拟现场工况的分度以及用二次非线性回归方法回归出误差修正公式两部分内容，叙述了二次非线性回归的理论推导过程，并通过实例对该方法进行了验证。     

浅论新时期高校图书馆的办馆理念

以人为本应该成为新时期高校图书馆的办馆理念。要在服务理念上以人为本，体现人精神，保证读权利的实现。要顺应趋势，在服务模式上以人为本，做好在转型期的服务工作。从以人为本的角度来看，我国高校图书馆的发展定位应该是复合型图书馆。高校图书馆即要做好传统印本献的服务工作，又要花大力气建设数字图书馆。     

铁路货运应对挑战的几点思考

近年来由于铁路货运市场占有率的逐年下降，使铁路货运面临严峻的挑战。铁路货运应该从转变经营理念，拓宽业务范围，开展增值服务以及物流人才培养和物流设施设备的建设等方面进行改革，予以应对。     

Rectangle expansion A*pathfinding for grid maps

Search speed, quality of resulting paths and the cost of pre-processing are the principle evaluation metrics of a pathfinding algorithm. In this paper, a new algorithm for grid-based maps, rectangle expansion A* (REA*), is presented that improves the performance of A* significantly. REA*explores maps in units of unblocked rectangles. All unnecessary points inside the rectangles are pruned and boundaries of the rectangles (instead of individual points within those boundaries) are used as search nodes. This makes the algorithm plot fewer points and have a much shorter open list than A*. REA*returns jump and grid-optimal path points, but since the line of sight between jump points is protected by the unblocked rectangles, the resulting path of REA*is usually better than grid-optimal. The algorithm is entirely online and requires no offline pre-processing. Experi-mental results for typical benchmark problem sets show that REA*can speed up a highly optimized A* by an order of magnitude and more while preserving completeness and optimality. This new algorithm is competitive with other highly successful variants of A*.     

基于无旋转原点的参考系转换方法及其计算

基于引入无旋转原点可以克服春分点的固有缺陷的特性,在分析GCRS (Geocentric Celestial Reference System,地心天球参考系)与ITRS(International Terrestrial Reference System,国际地球参考系)之间基于无旋转原点的转换过程基础上,计算了IERS(International Earth Rotation and reference systems Service,国际地球自转与参考系服务)1996、2003、2010等规范所推荐的3组转换参数的具体数值及其差异,并以太阳系10个天体为例进行了参考系转换计算.结果表明:IERS 2003、2010规范中推荐的2组转换参数间的差异较小,对坐标转换的影响在0.5 mas以内;IERS 1996规范中推荐的转换参数与另外2组转换参数间的差异较大,对坐标转换的影响在2.5 mas以内.基于无旋转原点转换和基于春分点的岁差章动转换2种方法间的差异对坐标转换的影响,在IERS 2003、2010规范中不超过5 μas,而在IERS 1996规范中由于未考虑框架偏差的影响导致差异较大.     

软交换承载网络组网模式分析与研究

针对软交换网络中信令流、媒体流和维护流等业务流的交互需求,结合SOFTX3000软交换设备、UMG8900通用媒体网关设备和UA5000用户接入设备相关单板的工作原理,分析了采用二层组网模式的承载网络存在的弊端,提出了基于OSPF(Open Shortest Path First,开放式最短路径优先)协议的三层路由组网模式,并在某电话局软交换网络中得到应用。经分析,采用三层路由组网模式相比于二层组网模式具有更高的安全性和可靠性。     

A review on carrier aircraft dispatch path planning and control on deck

As an important part in sortie/recovery process, the dispatch of carrier aircraft not only affects the sortie/recovery efficiency and safety, but also has severe influence on the carrier’s combat efficiency and the comprehensive support capability. Path planning is the key to improve the efficiency and safety during the dispatch process. The main purpose of this paper is to propose a comprehensive investigation of techniques and research progress for the carrier aircraft’s dispatch path planning on the deck. Three different dispatch modes of carrier aircraft and the corresponding modeling technologies are investigated, and the aircraft’s dispatch path planning techniques and algorithms have been classified into different classes. Moreover, their assumptions and drawbacks have been discussed for single aircraft and multiple aircraft. To make the research work more comprehensive, the corresponding tracking control methodologies are also discussed. Finally, due to the similarity of path planning problem between the carrier aircraft’s dispatch and those in other fields, this paper provides an exploratory prospect of the knowledge or method learned from other fields.     

圆柱形静电分析器的数值模拟

对美国DMSP系列卫星载60°圆柱形分析器的性能进行了数值模拟:以同时过松弛迭代法解Laplace方程,得到分析器内的势分布,由荷电粒子在分析器势场中的运动轨道以及传输概率的MontCarlo积分得出分析器的各种响应和几何因子．变动与分析器几何相联系的输入量,计算机程序可移用于其它圆柱形分析器.