Eclipse插件开发技术浅探

Eclipse平台是一个开放源码的、可扩展的、基于Java的集成开发环境(IDE).Eclipse本身不提供强大的用户功能,其全部功能都是利用其插件(Plug-in)机制来实现的.本文基于Eclipse平台的体系结构,重点分析了在Eclipse平台下进行插件开发的原理,并实现一个简单插件来展示eclipse插件开发的全过程.     

以信息技术改造传统产业,促进航空企业的跨越发展——成飞企业信息化建设的回顾和展望

简要介绍了成飞企业信息化建设的发展历程 ,重点介绍了成飞CIMS工程实施概况、特点和所产生的效益 ,并对成飞企业信息化建设前景做了展望     

测量机在FMS中的物理集成

系统介绍测量机在线数控测量单元中所采用方案的工作原理、机械结构、液压系统、控制系统．     

图书馆职业发展的"囚笼困境"研究框架

图书馆职业发展的"囚笼困境"是图书馆学领域中一个还没有引起足够重视的问题.此问题研究框架包括两部分内容:一是理论基础,二是研究内容.前者主要有图书馆职业理论、图书馆社会学和图书馆人力资源管理;后者主要包括基本理论、"安于现状者"的心理与行为分析、"受困者"的心理与行为分析、不同系统图书馆的"囚笼困境"比较、不同层次图书...     

基于系统分类和安全评估的无人机空域集成

无人机的空域集成,即无人机进入非隔离空域飞行与有人机共享空域,是未来发展的必然趋势,这也给空中交通管理带来了新的挑战.参照美国的空域集成计划,需要建立在空域详细分类的基础上,根据无人机的综合能力逐步实现无人机从单一空域到多空域,从隔离空域到非隔离空域的动态运行.而无人机的综合能力分类可以从体系划分和安全能力两个角度出发,综合衡量;其中,无人机体系基于自主能力和监管方式两个关键因素来划分.基于这种方法,分析可以初步确定一类无人机可以飞行的空域类型,以及跨越不同空域的方式,从而实现无人机空域集成.     

关于国家卫星导航产业政策体系建设的探讨

在全球卫星导航产业快速发展的时代背景下,我国卫星导航产业发展仍面临诸多问题和严峻挑战,顶层谋划并构建国家卫星导航产业政策体系的任务迫在眉睫。本文在开展实地调研、专家研讨和书面问卷基础上,分析了国家卫星导航产业政策体系建设的外部环境及机遇挑战,提出了国家卫星导航产业政策体系建设的总体思路、基本框架和亟待研究和制定的政策建议。     

Integration of GPS and low cost INS for pedestrian navigation aided by building layout

In outdoor environments, GPS is often used for pedestrian navigation by utilizing its signals for position computation, but in indoor or semi-obstructed environments, GPS signals are often unavailable. Therefore, pedestrian navigation for these environments should be realized by the integration of GPS and inertial navigation system （INS）. However, the lowcost INS could induce errors that may result in a large position drift. The problem can be minimized by mounting the sensors on the pedestrian＇s foot, using zero velocity update （ZUPT） method with the standard navigation algorithm to restrict the error growth. However, heading drift still remains despite using ZUPT measurements since the heading error is unobservable. Also, tbot mounted INS suffers from the initialization ambiguity of position and heading from GPS. In this paper, a novel algorithm is developed to mitigate the heading drift problem when using ZUPT. The method uses building lay- out to aid the heading measurement in Kalman filter, and it could also be combined for the initial- ization. The algorithm has been investigated with real field trials using the low cost Microstrain 3DM-GX3-25 inertial sensor, a Leica GS10 GPS receiver and a uBlox EVK-6T GPS receiver. It could be concluded that the proposed method offers a significant improvement in position accuracy for the long period, allowing pedestrian navigation for nearly40 min with mean position error less than 2.8 m. This method also has a considerable effect on the accuracy of the initialization.     

Research on uncertainty in measurement assisted alignment in aircraft assembly

Operations in assembling and joining large size aircraft components are changed to novel digital and flexible ways by digital measurement assisted alignment.Positions and orientations（P＆O）of aligned components are critical characters which assure geometrical positions and relationships of those components.Therefore,evaluating the P＆O of a component is considered necessary and critical for ensuring accuracy in aircraft assembly.Uncertainty of position and orientation（U-P＆O）,as a part of the evaluating result of P＆O,needs to be given for ensuring the integrity and credibility of the result;furthermore,U-P＆O is necessary for error tracing and quality evaluating of measurement assisted aircraft assembly.However,current research mainly focuses on the process integration of measurement with assembly,and usually ignores the uncertainty of measured result and its influence on quality evaluation.This paper focuses on the expression,analysis,and application of U-P＆O in measurement assisted alignment.The geometrical and algebraical connotations of U-P＆O are presented.Then,an analytical algorithm for evaluating the multi-dimensional U-P＆O is given,and the effect factors and characteristics of U-P＆O are discussed.Finally,U-P＆O is used to evaluate alignment in aircraft assembly for quality evaluating and improving.Cases are introduced with the methodology.     

航空发动机新型补燃增推燃烧室的现状与发展

涡轮后框架一体化加力燃烧室（简称涡轮后框架燃烧室）和涡轮间燃烧室均是为了提高推进效率和降低耗油率而新近开发和验证的2种先进补燃增推燃烧室。综述了2种燃烧室的基本结构、研制背景、发展历程和目前研究进展,总结了从众多研究中获得的这2种燃烧室相对常规结构的性能特点,如涡轮后框架燃烧室结构紧凑,流体损失小,结构耐久性好;涡轮间燃烧室推进效率高,热效率高。还指示了这2种燃烧室的发展趋势。