一种低成本无控火箭点火时序控制器设计

基于无控火箭设计了一种低成本多路点火时序控制器,系统以STM8为控制器,采用震动开关完成火箭计时零点的采集,按照既定流程,完成火箭的时序控制;由于整系统涉及火工品运输及发射,因此设计了一套完整的电路与软件流程,完成火工品安全保护、火箭时序装订,火工品阻值检测、时序控制器自检及上报、过载检测,火工品点火,故障上报及处理等功能;系统在地面的自检率为85%以上,适用于小于1A 50 ms敏感火工品点火,点火时间精度误差不大于10 ms;试验结果表明,控制器可以在-20~50℃工作,可应用于增雨防雹火箭、探空火箭以及模拟训练火箭等领域,用户可以根据不同的火箭发动机选择过载检测时间,根据点火头引爆参数,选择不同的容值的电路参数,根据不同流程,装订不同的时序,完成精确的无控火箭时序控制。     

具有负载电流检测的高速固态继电器接口电路设计

在姿轨控发动机地面试验中,需要控制快响应电磁阀的开闭,同时准确地测量负载电流。针对应用中的问题,实现了一种高速固态继电器接口电路。设计了用于各路控制信号隔离、逻辑判断和放大的数字控制电路,可切换共正/共负的负载模式,抑制感性负载反电势的负载电路,以及具有隔离输出的电流检测电路。误差分析和测试校准证明本电路对控制信号传输延时不超过150ns,电流检测精度达到0.2074%,可广泛适用于各种控制器与固态继电器的接口以及电流检测应用中。     

基于PXI总线的单项点火试验测试系统的设计与实现

为了准确测量固体火箭发动机点火装置点火性能的相关参数及P-T曲线,研究并设计了一套基于PXI总线的点火装置单项点火试验测试系统;分析了点火装置点火性能对小型固体火箭发动机的重要性和点火试验测试系统的功能,阐述了点火试验测试系统的设计方案及硬件组成、软件设计和关键技术;对某型号点火装置进行单项点火试验测试,实验结果表明,该系统能够准确测量点火装置的点火性能参数,满足了点火试验测试要求,具有一定的军用价值和推广价值.     

火炮试验用同步时序控制系统设计

同步时序控制系统是火炮试验中的重要控制仪器,主要用于试验中的火炮点火控制、高速像机、数采系统等测试设备的同步触发时序控制,其时序控制精度关系到火炮试验数据采集的成败;详细介绍了一类火炮试验用同步时序控制系统的软硬件设计技术,系统包含6路输出控制通道,通道间的时序控制精度为40μs,各通道时间脉宽在10s内可调,利用PCI总线模块与硬件定时技术实现时序精确控制,利用LABVIEW设计时序模拟显示界面,系统操作简单安全可靠,完全满足靶场火炮试验时序控制需求。     

基于USB和串口通信的点火能量测试系统设计

为改善某型煤油发动机的冷启动性能,需测定发动机电感式点火系统在不同充磁时间下的点火能量,设计了一套点火能量测试系统,利用VC++开发了点火能量测试软件,实现了测试软件与数字示波器及点火控制器的通信,并进行了点火能量测试。试验结果表明,该测试系统能够准确地测试点火能量。     

基于MC9S12微控制器的发动机高能直接点火控制

发动机高能直接点火系统需按点火顺序、点火时刻和点火能量的要求实现各点火线圈的独立控制。介绍了以MC9S12DP256微控制器为核心的电子控制单元的软硬件系统设计。利用MCU的增强型捕捉定时器,将输入捕捉与输出比较功能相配合,满足了6个点火线圈初级电路通断电的复杂时序控制要求。该系统在某稀燃天然气发动机的开发中进行了应用,结果表明:在各种工况下,都能获得可靠的点火。     

基于PXI总线多通道时序监测电路系统设计

通过对箭载发动机的时序监测方法进行研究、分析,设计出一款基于PXI总线多通道时序检测电路系统;介绍了系统的软硬件结构和功能,设计了输入光电隔离电路、数字消颤电路、数字跳变检测电路、计时器电路、FIFO存储器电路和PXI总线接口电路,在Labwindows/CVI环境下开发了测试系统软件,并通过控制测试设备实现对箭载发动机的时序监测;时序监测电路系统已经应用在导弹和火箭发射地面测试发射控制系统中,经过多次测试和发射场真实发射试验验证,达到了预期效果。     

可编程控制器在卫星发射设备中的应用

众所周知,控制卫星发射的设备,其可靠性、稳定性、延时精度等直接关系到发射的成败。为了做到控制设备的万无一失,必须对原运载工具、发动机点火控制系统进行技术更新。原系统实际上是一个多级顺序脉冲发生器,存在可靠性、稳定性、精度等问题。采用FX_2-48MR可编程控制器为核心的点火控制系统,提高了可靠性、稳定性、延时精度,同时延长了使用寿命。经过多次模拟试验和环境试验,各项技术指标符合要求。在执行某次卫星发射任务中,顺利完成了点火发射控制,取得了成功。     

一种点火控制系统自动测试设备设计与应用

点火控制系统在地面测试阶段往往会进行多次重复性测试,以便及时掌握点火控制系统在经历不同试验后的性能状态情况,为了在保证测试精度和测试稳定性的同时提升测试效率,设计研制了一种点火控制系统自动测试设备,搭建出基于PXI总线的控制系统,实现对点火控制系统的供电控制、数据采集和性能验证等功能,以LabVIEW开发平台设计了对应的测试软件,经实际试验验证,所搭建的测试设备能够以较高稳定性和精确度实现对点火控制系统的功能性能测试。     

航天器热试验电缆自动测试装置的设计与实现

为了解决航天器热试验测试电缆导通和绝缘测试人工工作量大、效率低的问题,设计并实现了基于继电器网络的自动化测试装置。系统以EB3680嵌入式工控机为主控制器,实现对测试电压产生和继电器开关的控制,通过对测试时序的控制优化,缩短了测试时间。进行了接口单元和继电器单元的模块化设计,提高了系统的适用性和可扩展性。基于VC 6.0平台完成了软件开发,能够完成人机交互,测试结果判读,数据处理、显示和存储。通过USB-UART实现了上位计算机和测试装置的数据传输。实际应用表明该装置工作稳定,自动化程度高,测试时间短,能够有效提升测试效率和可靠性。     

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.