一种新型三轴加速度过载模拟系统

针对飞行过程中飞行器机体承受的轴向、法向、切向三个方向的加速度过载存在耦合性强、变化速率快、模拟难度大的特点,提出了一种以离心机为平台的三轴加速度过载同步模拟系统。给出了飞行器坐标系和飞行器三轴加速度过载的定义,介绍了该模拟系统的整体结构和模拟过程的具体实现方法,分析了三轴加速度过载投影原理和三轴加速度解耦控制算法,建立了基于Pro/Engineer和MATLAB的三轴加速度过载模拟系统的机构运动模型,实现了联合仿真。仿真结果表明,该系统可有效模拟飞行器飞行过程中三轴加速度过载的同步变化,同步性好、精度高、实时性强。该系统可以作为飞行器或机载设备的地面环境试验测试平台,有助于科研人员及时发现结构设计中的缺陷,从而改善飞行器的性能,具有重要的科研意义和广阔的应用前景。     

高精度宽量程智能气源控制系统研究

气源控制系统作为气介质来源，是压力控制系统的重要组成部分，也是气体压力参数的测试、校准的基础。在气体压力参数的测试、校准中，使用的校准装置或测试设备需要外接气源系统。传统压力源通常都是正压、负压分开，使用中不能自动切换，通常还需要手动操作减压阀以得到相应的气源压力。为满足现场压力测试、校准中对宽量程供气的技术需求，对宽量程输出气源技术进行了研究，利用压力控制的设计方法和原理，设计了一种高精度宽量程智能气源控制系统。创新性地将负压、常压、高压气源进行宽量程集成设计，达到了0.5%FS的输出准确度和稳定性，满足了压力测试、校准中高准确度、宽量程、智能的供气需求。     

通用惯导测试仿真系统的设计与实现

惯导性能测试一般在地面实验平台上进行,只能得到离散状态的测量结果,不能满足分析整个系统性能要求。建立飞行仿真系统能模拟各种飞行模态,并能够对惯导性能进行动态连续飞行轨迹下测试,在工程应用上具有重要意义。提出了惯导性能测试仿真系统的结构框架,并进行了系统功能分析与硬件设计,采用模块化设计思想,构造了基于控制律的飞控仿真模块及惯导反解算、通信等软件模块,给出了详细的设计及实现方法,并使用VC进行算法、系统实现。与惯导系统的联合仿真证明,为惯导测试系统的设计提供有效的平台。     

基于LabWindows/CVI的计算机图形动态模拟技术

计算机图形动态模拟是动态测试CAT系统的重要组成部分，本文提出了利用Labwindows/CVI实现动态模拟的基本原理与方法，并给出了拖拉机动态测试系统中仿真控制的实例，动态模拟功能设计成为相对独立的模块，有利于实现测试系统的自动化监控和操纵。     

大气数据仪表校验系统的设计与实现

针对飞机大气数据计算机和测试仪表的校验问题,在分析了大气数据仪表的特点的基础上,基于嵌入式计算机控制技术和精密气压控制技术,提出了一种智能大气数据校验系统的设计方案;从控制方面,系统采用双传感器、普通硅压阻压力传感器和数字石英压力传感器,模拟传感器具有高速响应特性,将其作为过程控制传感器,保证装置的动态响应性能;数字石英压力传感器的精度达0.01%F.S,作为基准压力传感器,保证系统准确度;采用双闭环控制方案,模拟闭环采用电子电路设计实现,采用模拟硅压阻压力传感器和模拟PID控制电路构成模拟控制闭环;采用数字式压力传感器和计算机构成数字PID控制闭环,数字闭环通过计算机、数字传感器、软件、串口和计算机串口实现;实验证明,该装置升降速度的输出准确度优于0.02%F.S,控制稳定性0.002%F.S。     

基于VxWorks的复杂飞行器模拟平台设计

为了满足多接口、多状态、多任务的复杂飞行器测试需求,设计复杂飞行器模拟平台,基于器上综合电子系统实现飞行器电气系统软硬件接口测试。飞行器模拟平台采用主控机和模拟器两级控制架构,主控机基于WPF框架实现人机交互,完成对模拟器的指令控制;模拟器运行在VxWorks系统下,基于WorkBench开发环境对指令进行实时解析,驱动各功能模块执行动作。试验结果表明,该平台实现了飞行器上各系统电气接口的模拟,保证了器上综合电子系统的高测试覆盖性。     

飞行器供配电系统地面通用测试接口设计

供配电地面测试负责为飞行器提供模拟供电、控制状态切换、采集并传输系统状态信息,配合完成全飞行器全周期的综合测试任务;飞行器与地面测试系统之间接口复杂,各项目接口方式也不统一,导致测试系统中专用设备比例仍然很高,设备继承性和互换性不强,研制费用高;首先简要介绍了供配电地面测试系统的基本功能和设备组成,明确各组成部分之间的能源流和信息流,然后对供电、控制、测量的典型接口电路进行分析,从实现方式上进行简化和归类,最后提出基于先进背板总线架构的模块化板卡方案实现测试设备的接口通用化设计;经实际产品研制和系统测试,能够满足飞行器从综合试验到靶场测试发射的全生命周期测试需求,已在两个项目中实现产品共用,经济效益明显,为电气系统地面测试设备通用化研究提供了支撑。     

基于LAN的转台机动控制虚拟动态测试分析系统设计

针对卫星姿态机动控制地面物理仿真监测实验,设计了卫星姿态机动控制性能动态测试分析系统;测试系统采用码盘作为测角传感器、数字I/O接口卡、测试目标为飞行器仿真气浮单轴实验转台,Labview和Access为开发软件;运用了动态测试技术、Lab-view与SQL连接的ADO技术,设计了库结构,利用Datasocket技术实现了实验数据的网络通讯,并介绍了系统硬件设计方法和软件系统设计方法,该系统实现了角度动态数据采集、数据自动存储、数据自动分析、数据管理及数据自动打印等实验功能,分析结果包括机动范围、姿控精度、控制误差及机动响应时间等数据项,还实现了局域网内PC机在线实验观测和实验数据备份功能;经实验验证,达到预期的实验测试任务要求。     

气源环境监控系统设计与实现

针对高压氮气气源装置需要对入口、出口的气体压力和露点进行高精度测量和对电磁气压阀进行程控的需求,设计了一套气源环境计算机自动监控系统;首先简介了系统的基本结构,然后重点讨论了自行设计的放大滤波电路、信号调理卡以及基于PCI9112卡的信号采集、对电磁气压阀程控的软件设计方法;最后通过对实验数据的分析,提出了提高测量精度的具体措施;该系统在多种型号红外武器地面试验中,测量精度高、控制精确且工作稳定,保障了气源装置的安全运行。     

基于Labview的卫星电源地面监控系统研究

采用Labview平台、基于SQL Server设计并开发了一套能在卫星电源分系统的设计和开发阶段对其充电进行均衡控制并对相关性能进行测试的地面监控系统;介绍了卫星电源地面测控系统的组成和软件总体框架,详细阐述了软件主要功能,包括实时监测程序、在轨状态仿真控制程序、数据的保存、回放和维护程序等关键技术的实现方法;测试结果表明,该监控系统监测数据准确,采样精度优于0.1%,运行高效可靠。     

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。     

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.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.