一个计算机售票系统的教学实例

本文介绍了一个用于民航运输专业管理信息系统课教学的教学实例。该实例以民航售票业务流程为基础,通过分析现行手工系统业务流程,得出现行系统流程图及概况表,进而得出计算机售票系统数据流程图,通过组织学生根据该流程图编程,可提高学生在实际工作中操纵、开发计算机售票系统的能力。     

Advanced Development of ESG Strapdown Navigation Systems

The fundamental problem of inertial navigation, double integration of acceleration to obtain position, is defined and discussed. Mechanizations of both space-stable and local-vertical platform systems are exhibited. The synthesis problem for an electrically suspended gyro (ESG) strapdown system is defined and discussed: readout, readout errors due to vehicle motion, synchronization of readout with system computer, alignment, correction and calibration for mass unbalance drift, and digital mechanization. Alignment, calibration, and acceleration measurement are also discussed. Sources of error involved in the electronic gimbaling including those peculiar to strapdown configuration are discussed and compared to mechanically gimbaled systems. Advanced developments required in the component and systems areas are listed, and it is shown that such development will lead to reduced complexity, higher accuracy, and increased reliability and utility for inertial systems.     

末敏弹减速运动和稳态扫描段运动特性的研究

对末敏弹这一全新反坦克武器在减速运动和稳态扫描段的运动特性进行了仔细的研究。恰当地引入了降落伞的附加质量和附加惯性矩,完整地分析了伞体和弹体所受的外力和外力矩,建立了由伞体和弹体组成的末敏弹系统二体运动模型。编制了完整的计算程序。给出了末敏弹扫描角速度、扫描角和扫描曲线随时间的变化,以及扫描覆盖区随高度的变化。计算结果与试验结果有很好的一致性。该模型可进一步用于末敏弹系统的弹道修正、参数优化和弹道模拟。     

电子航图在通用航空飞行准备中的应用

以一个飞行准备辅助系统的开发为例，详细介绍了电子航图在通用航空飞行准备中的应用技术和方法，包括地理信息、航行资料和机型性能数据库的建库技术以及航线准备、飞行计划制定方法等内容，可供相关系统的开发人员借鉴。     

Wearable computers open a new era in support resource management

Our aerospace customers are demanding that we drastically reduce the operating and support costs of our products. In today's aerospace maintenance environment, the vast majority of maintenance technicians are using paper technical publications, with fixed troubleshooting trees, and manual or semi-automated post maintenance documentation. Interactive Electronic Technical Manuals (IETMs) are at this time being deployed with portable maintenance aids, often an electronic notebook-sized data presentation system, some with expert system based troubleshooting aids. Many of the IETM based systems still require post maintenance documentation and, the maintenance control function is at best, updated when each maintenance task is completed and the vehicle departs. Advances in wearable computer technologies allow us to integrate the maintenance technician with a highly automated, tightly managed support system that will significantly reduce support costs and turn-around times while improving the quality of maintenance. A “Portable Maintenance Terminal” is a wearable computer configured to meet a maintenance technician's information and communication needs. The Portable Maintenance Terminal (PMT) will place the maintenance technician in the loop with the support system. Wearable computers are intended for use in locations where easy access to a desktop computer or laptop is not practical, or where operators are required to have their hands on the job rather than being busy with a computer. The wearable PMT can provide a hands-free, heads-up, networked computing environment     

综合导航系统信息融合模拟仿真平台设计CSCD

为解决综导系统的信息融合问题,设计了一种新型的综导系统信息融合模拟仿真研究平台。平台包括综导信息融合模拟评估导调台、惯性类导航设备模拟器、非惯性类导航设备模拟器、综合导航模拟器、电子海图系统和数据分析服务器六大模块。导调台采取一种新的船舶运动参数发生器模拟生成多种海况条件下船舶运动参数;综合导航模拟器采取多种融合算法并行运行方式,以方便比较不同算法的性能;数据分析服务器采用高性能计算机模拟公共计算环境,可研究适应未来船舶软硬件计算资源的信息融合方法。系统测试表明,基于平台的导航信息融合流程和效果满足要求,所设计的平台系统功能正常,可直接用于舰船信息融合算法的设计、分析、测试评估等工程研发工作。     

首都机场航站区地面信息管理系统（CATS—II）方案探讨

首都机场航站区地面信息管理系统是航站区各电子系统的核心。系统建有强大的中心数据库，负责采集、处理、存储、发布航站区内航班信息、地面站坪、气象、设备运行状态、商务的客、货、邮、行等等大量信息。通过计算机网络把相关的电子系统联网实现系统集成。     

基于Cardinals三次样条曲线的航迹生成算法实现

根据军用飞机飞行参数记录系统提供的飞行数据, 提出了一种利用Cardinals三次样条曲线进行航迹生成的算法。经过对离散点航迹误差修正及样条曲线的讨论, 给出了实时计算任意时间点飞机质心位置的公式, 为开发可在普通PC机上运行的军用战机飞行过程再现软件, 提供了条件。     

机载电子设备地面仿真检测系统

 本文讨论机载电子系统地面仿真检测系统的系统功能,硬件软件结构,给出一个实际的仿真检测系统,它由11台不同类型微机通过8端光纤通信网络连成一个分布式仿真测试网,能够模拟雷达运动目标信号,导航计算机、大气数据计算机、导弹控制计算机信息,能够进行实时数据处理、绘制目标运动曲线,打印测试参数报表等。     

关于计算机2000年问题的探讨

计算机２０００年问题已引起人们的普遍关注,必须在进入２０００年前予以妥善解决。对其可采用修改应用程序、更换系统软件、更换硬件设备等多种办法进行处理。在应用程序的修改中采用变形的日期移位法是对大多数办公系统容易实现且又行之有效的办法。     

Improving the productivity of complex electronic systems design byutilizing applied design methodologies

The design process of complex electronic systems consists of four traditional main stages, which are system design, electronic design, mechanical design, and design for manufacturing. Even today when many integrated computer aided design environments are in use for electronic systems design, we still seem to accept that the design process really has to follow this path of four individual design stages. It is common that we are dealing with data transfer problems between different types of CAE-applications. However, there is a possibility to avoid the disadvantages due to integration problems between the design stages if we decide to develop the design methodology itself instead of developing those independent software applications. One effective way to improve the productivity of complex electronic systems design is to tune the so-called systematic design approach by adding special aspects of electronic systems design into the questionnaires used for collecting the requirement lists for further mechanical design and DFM. Another important tool is the carefully made manufacturability analysis. The deep interaction of mechanical and electronic design, extended by manufacturability analysis can also lead to innovative solutions as presented previously by the author. In the article entitled “Manufacturability Analysis-A Useful Subset of Systems Engineering” we were able to show that the number of iteration cycles during the different design and manufacturing stages could be reduced by 50% compared to the conventional design methodology. In this paper, we illustrate additional tools to continue this promising development work     

全站仪检测数据管理系统

介绍了全站仪检测数据管理系统。本系统以FoxPro for Windows为基础，采用模块结构，具有对检测数据录入修改，自动转换，成果计算，查询显示等功能，实现了系统数据管理和处理的一体化。     

RESEARCH ON THE METHODS OF IMPROVING DGPS POSITIONING PRECISION

A DGPS positioning model is described, and the elements that influence DGPS positioning precision are analyzed in detail. On this basis, the methods of improving DGPS positioning precision are proposed which include increasing updating rate of DGPS correction, building extended DGPS system and improving quality of DGPS correction signal. In the intelligent monitor and control system of the public transport in Beijing, these methods improve the vehicle positioning precision to 2～5m.     

Electronic prototyping

Progress in automation will require the ability to electrically represent, reason about, and manipulate objects. The author examines the issues involved with electronic prototyping from the point of view of a computer scientist and discusses the development of representations, languages, editors, and model-driven simulation systems needed to support it. In particular, he identifies areas where basic research is needed before further progress can be made     

Integrated flight control systems: a new paradigm for an old art

The automatic flight control computer was a revolutionary development in the early days of flight, even in its primitive electromechanical form. It evolved into an electronic computing device, starting as an analog computer and maturing into software run on a digital, general-purpose microprocessor. The current accepted industry standard is to use a dedicated microprocessor in its own enclosure for this function that is essentially firewalled from the rest of the systems on the aircraft. This paper will explore the opportunity to integrate the flight control function into an integrated processing platform, which is a robustly partitioned platform that supports multiple functions of dissimilar design assurance levels. This approach provides all of the benefits of an integrated system, while still maintaining the separation provided by a stand-alone unit. The paper will consider both the advantages and disadvantages of this approach. The discussion will describe each of the alternatives in general and then focus specifically on autopilot and flight control functions that have potential for integration. The end goal of the paper is to impress on the reader an understanding of the different alternatives available for autopilot, flight control, and avionics modernization in general. This includes the development of a selection matrix that will assist the reader in making decisions on how best to implement these functions according to criticality and the volatility of their future requirements     

计算机辅助工艺过程尺寸设计

本文基于工艺过程设计中尺寸图表技术建立了用于计算机辅助工艺过程尺寸设计,称为阵-树-链的数学模型。同时构造了用于工序尺寸偏差确定及分配的算法。简单介绍在VAX11/750计算机上开发的交互式计算机辅助工艺过程尺寸设计系统CADP（Computer Aided Dimensional Planning）。     

Application of Ground/Air Data Link to General Aviation Operations

The Federal Aviation Administration (FAA) is currently upgrading secondary surveillance radars with systems which will have an integral data link capability, the Mode Select (Mode S) beacon system. These new systems will allow two-way data communications between ground systems (e.g., weather databases and Air Traffic Control (ATC) systems) and aircraft that are equipped with data link compatible Mode S transponders and suitable display and input devices. Initial data link services include both weather information and ATC advisories. The MITRE Corporation* is developing an in-house capability to perform end-to-end operational evaluation of data link services. Initially, a low-cost, portable pilot position man-machine interface is being developed for use in general aviation operations. The objective is to explore operational issues in laboratory and limited flight test environments, and to demonstrate these services on a data link I/O device, a laptop portable personal computer (PC) with touch panel. A group of pilots will bench test the interface design, and the results will be incorporated into the design used in flight testing. This paper describes the project's objectives and results to date, including implementation details and pilot test results.     

可重构的卫星/运载复用电子系统设计

采用小型运载器能够降低卫星发射成本,针对小型运载器运载能力有限的情况,通过卫星与运载电子系统特点分析,提出可重构的卫星/运载复用电子系统设计方案。该方案采用基于总线的混合结构,并将可重构计算技术应用于中心计算机的设计,利用片上可编程系统（SOPC）、软硬件协同设计以及硬件描述语言（HDL）设计等技术完成系统功能。通过对现场可编程门阵列（FPGA）的重构,星载计算机实现对运载器与卫星的控制与管理,并能够进行故障处理及在轨升级。构建地面实时仿真系统并进行仿真测试,得到重构时间在（500±40）ms范围内、〖JP〗控制周期可达10 ms的仿真结果,验证了本文所提出方案的可行性与系统重构的有效性。通过硬件的分时复用,复用电子系统能够有效降低发射成本,并解决系统资源、多功能与高性能需求之间的矛盾。     

基于PCI总线的电子舱信号群高速采集系统

设计并实现了一种基于PCI总线的高速数据采集系统,主要包括模拟输入、信号调理、模数转换、数据传输存储以及计算机接口等部分.此系统可用于对某型号电子舱信号群进行实时高速采集,其性能和指标均满足要求.     

Digital Electronic Flight Decks: The Outlook for Commercial Aviation

Digital avionics technology shows great promise in reducing overall airplane system cost. The new digital electronic components are very reliable and offer great flexibility in application. Development of modular control units, for the directional controls and engine throttles, will aid standardization and gradual refinement of such control devices. A network of multisystem digital data buses can be developed to handle the complex interchange of data between interrelated systems throughout the airplane.