卫星姿轨控分系统仿真测试平台的设计与实现

卫星控制分系统地面测试系统的设计是姿轨控分系统设计的重要部分。本文经软、硬件的充分论证后给出了基于PXI总线的硬件采集系统和XPC软件仿真环境下的卫星姿轨控系统综合仿真测试的设计方案,并结合某型号卫星姿轨控分系统的测试需求进行具体的项目开发;实践表明该测试系统具有较强的可扩展性和二次开发能力、结构灵活、体积小、测量精度高、抗干扰能力强等优点,可以应用于相应的中低轨道卫星的控制分系统测试。     

测试序列管理

测试语言是卫星地面测试总控软件的核心 ,用户通过使用测试语言来编写测试序列程序 ,来对卫星的内部各分系统进行测试 ,以保证卫星的可靠运行。本文介绍了我们在研制卫星地面测试总控软件中研制的测试序列管理系统。     

测试序列管理

测试语言是卫星地面测试总控软件的核心，用户通过使用测试语言来编写测试序列程序，来对卫星的内部各分系统进行测试，以保证卫星的可靠运行。本文介绍了我们在研制卫星地面测试总控软件中研制的测试序列管理系统。     

卫星星座综合测试系统研究

卫星星座等多星并行研制生产带来了多星并行综合测试的新课题.介绍了一套卫星星座模式下的综合测试系统,该系统由总控设备和各分系统专用测试设备组成,通过标准网络和通信协议形成统一指挥和调度的卫星电气综合测试体系.详细介绍了系统的总控设备以及各分系统专用测试设备,并分析了地面综合测试系统的信息流.该系统可靠性和可扩展性程度高,为多星并行综合测试系统的模块化、通用化和系列化提供了一个有效的参考,满足了卫星星座多星并行综合测试的需要.     

卫星分系统仿真测试平台设计与实现

卫星三级测试包括设备级测试、分系统级测试和整星级测试,测试成本较为昂贵,为了达到尽早的开展分系统级测试的目的,提出了一种数字仿真环境同单机设备相结合的分系统仿真测试平台的设计方法;通过对各单机设备进行仿真建模,并依据设备间的数据交互方式进行物理实现,为单机设备构建分系统级的测试环境;解决了在缺少单机设备时无法开展分系统级测试的难题;尽早的对单机设备进行分系统级测试,可以在早期就发现单机设备存在的缺陷并进行改正,从而达到节省测试成本的目的。     

高低温试验室样机测试系统设计

为解决高低温环境试验被试样机的"冻透"/"热透"试验条件判定问题,满足最新环境试验标准中对样机启动参数、各分系统温度参数和试验仓温湿度测试的要求,提出基于PXI+SCXI总线的样机测试系统的硬件设计方案,并在LabWindows/CVI软件开发环境下完成了软件界面及分析算法设计,实现对样机和环境温湿度等参数的测试、监控与评判;实际应用表明,该测试系统具有工作稳定性好、测试精度高、适应性强等优点,满足高低温试验室样机测试要求。     

卫星姿轨控半物理仿真测试系统

为了保证卫星发射前的地面姿轨控半物理试验的顺利进行,研制了姿轨控分系统半物理仿真地面测试系统。为了满足相关类似卫星型号的通用化测试,本套仿真测试系统采用通用模块化的设计架构,同时采用现今主流的PXI总线测试技术（配合VPC转接电路板）。使用标准通用cPCI总线板卡以及部分自制FPGA可编程cPCI总线板卡实现各测试模块的功能。这种架构不仅能实现功能模块化,便于后续的功能扩展及维修,同时具有可靠性高、搭建时间快、可维护性强的优点,且体积小,稳定性强,能适应不同测试对象的测试环境条件,适合长途运输。本文介绍了系统的总体设计结构,重点介绍了模拟总体电源、动力学仿真机、电信号源、程序加载以及外围设备等硬件系统功能,以及相关配套软件的基本功能。测试系统经过与卫星的星地联试,功能性及使用性均得到了验证,测试结论符合设计之初功能性及通用化的构想。     

卫星GN&C分系统建模与仿真软件实现

卫星系统的总体设计以及在轨运行等任务都离不开对其制导、导航与控制(GN&C)分系统的设计、优化与仿真演示,但GN&C分系统方案以及算法的复杂性对于GN&C分系统的快速设计、仿真与决策非常不利.采用Matlab/Simulink作为后台计算引擎、利用Matlab与VC混合编程,设计实现了一个卫星GN&C分系统建模与仿真软件环境.该软件环境能够屏蔽GN&C分系统的构建细节从而快速搭建具体的仿真应用,可实现对卫星GN&C分系统方案的快速仿真评估,并实现建模环境与具体的仿真应用相分离.     

卫星GN&C分系统建模与仿真软件实现

卫星系统的总体设计以及在轨运行等任务都离不开对其制导、导航与控制（GN&;C）分系统的设计、优化与仿真演示,但GN&;C分系统方案以及算法的复杂性对于GN&;C分系统的快速设计、仿真与决策非常不利。采用Matlab/Simulink作为后台计算引擎、利用Matlab与VC混合编程,设计实现了一个卫星GN&;C分系统建模与仿真软件环境。该软件环境能够屏蔽GN&;C分系统的构建细节从而快速搭建具体的仿真应用,可实现对卫星GN&;C分系统方案的快速仿真评估,并实现建模环境与具体的仿真应用相分离。     

NI推出GPS接收器测试工具包

2008年7月,美国国家仪器有限公司（National Instruments,简称NI）近日发布了NI LabVIEW GPS工具包,这是一款图形化系统设计环境下的扩展工具包,使NI RF PXI平台可用于多卫星GPS信号仿真。通过NI LabVIEW软件创建波形来仿真多达12颗卫星（L1波段的C／A编码）,工程师可以使用NI PXIe-5672射频矢量信号发生器测试GPS接收机特性,如灵敏度、首次定位时间（TTFF）以及定位精度等。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.