具有外部干扰的二阶多自主体系统的协同运动

为解决多自主体系统在群集运动过程受到外部干扰影响的问题,本文研究了具有外部干扰的二阶多自主体系统的分布式协同控制.本文中的外部干扰包括匹配干扰和不匹配干扰,针对系统中的匹配干扰,设计了状态观测器和干扰观测器,对系统的未知状态和干扰进行估计,并且构造了基于干扰观测器的多自主体协同控制算法.对于系统中的不匹配干扰,设计了与匹配干扰不同的干扰观测器,构造了基于主动抗干扰观测器的协同控制算法.运用矩阵论和现代控制理论等方法,研究了基于干扰观测器的二阶多自主体系统的协同控制.应用计算机仿真分别验证在多自主体系统具有匹配干扰和不匹配干扰的情况下结论的有效性,仿真结果表明,本文所设计的多自主体协同控制算法可以使跟随者最终都收敛到领导者的状态,实现了具有匹配干扰和不匹配干扰的二阶多自主体系统的状态一致性.     

双源渠道闭环供应链生产计划的一种干扰恢复模型

研究双源渠道闭环供应链生产计划调度中的干扰问题,从双源渠道供应、正向制造和逆向再制造等5个方面分析了供应链中的不确定性和干扰问题;然后建立一种干扰恢复模型,采用基于干扰恢复思想的双模糊PID控制器,针对各种随机离散型和连续型干扰事件的参数进行优化和干扰恢复,并从鲁棒性、干扰损失、库存扰动3个指标对系统稳定性和干扰进行量化分析;最后通过一个仿真案例,表明所提出的方案比无干扰恢复的方案具有更高的鲁棒性和更低的干扰损失．     

基于雷达探测概率的干扰效能评估

对电子战中压制式干扰的干扰效能的有效评估问题进行了研究.首先分别利用无干扰状态和干扰状态的雷达探测距离求解了信噪比和信干比的表达式,进而建立了两种不同状态下的探测概率模型.然后通过模拟干扰机的自卫干扰和支援干扰场景,在设置雷达参数和干扰参数后,仿真比较了3种不同RCS的目标在上述两种干扰模式下雷达探测概率的变化.最后对压制干扰效能进行了科学评估.评估结果表明:干扰机的压制干扰能够有效降低雷达探测性能,自卫干扰时,大幅提升自身的安全性;支援干扰时,提高目标机的突防生存力.     

基于混沌粒子群算法的项目调度干扰问题研究

针对资源受限项目调度问题中的干扰情况进行了界定, 面向几种干扰问题建立了相应的资源受限项目调度干扰模型和混沌粒子群求解算法, 对项目网络图干扰、任务干扰和资源干扰三种干扰问题进行仿真计算, 验证了算法和模型的有效性, 为决策者在干扰事件发生后及时对原最优调度计划作出调整给出了方向。     

基于 MatLab的有源压制性干扰信号模拟与实现

计算机仿真是研究雷达干扰系统效能的有效方法。有源压制性干扰是雷达干扰系统中常用的一种信号,通过分析压制性干扰的原理,在 MatLab平台建立模拟和产生干扰信号的仿真模型,得到宽带阻塞式干扰、窄带瞄准干扰和扫频干扰三种典型压制性干扰信号的仿真结果,验证三种干扰信号对雷达系统的干扰效能。所搭建的仿真模型可作为雷达对抗系统效能评估的干扰信号源。     

基于辅助分类器和变分自编码生成对抗网络的干扰识别

针对基于深度学习干扰识别方法在小样本集情况下性能恶化问题，提出一种基于辅助分类器和变分自编码生成对抗网络(AC-VAEGAN)的干扰识别方法。利用生成对抗网络和变分自编码器的核心思想设计识别模型，得到连续有意义的干扰样本集潜在空间；确定编码器、生成器和鉴别器的损失函数，且鉴别器采用动态学习率的优化算法，使得模型训练过程更加有效且稳定。仿真结果表明，在干扰时频图小样本数据集情况下，当干噪比为-10 dB～10 dB时，该方法对宽带噪声干扰、部分频带噪声干扰、单音干扰、多音干扰、脉冲干扰、跳频干扰、线性扫频干扰和二次扫频干扰这八种干扰的正确识别率均高于ACGAN和CNN。     

对步进频雷达灵巧干扰的建模方法与仿真

步进频雷达的频率跳变和相关处理特性使得传统的噪声干扰的利用效率下降,必须寻找新的干扰样式.分析了步进频信号的一维成像原理和模糊函数性质,根据步进频雷达信号处理的特点,提出了对其灵巧干扰样式的建模方法,由此得出了几种典型的和特殊的干扰样式,并对干扰效果进行了仿真分析.理论和仿真结果表明:相较于传统的噪声干扰,灵巧干扰能更加有效地实施干扰.     

基于LFM波形的灵巧干扰效能分析

针对电子对抗作战中普通干扰信号难以对脉冲压缩雷达产生有效干扰问题,提出了一种基于线性调频波形的灵巧干扰信号.依据线性调频波形设计原理,在对波形信号进行间歇采样转发后,建立了灵巧干扰的干扰信号.通过设置间歇采样占空比0.2和0.5,仿真得到了不同占空比下灵巧干扰在时域和频域的幅度分布情况,并经过匹配滤波输出,进一步获得了灵巧干扰分别在压制干扰时和欺骗干扰时的时频联合分布结果.仿真结果表明:间歇采样占空比较大时体现欺骗干扰效能,占空比较小时体现压制干扰效能,即灵巧干扰通过匹配雷达波形具有较强的干扰灵活性和针对性.     

一种测量工业环境感应传导干扰的方法

针对采用干扰测量仪或频谱分析仪只能测量工业环境中干扰源的辐射干扰强度的问题,提出了一种测量工业环境感应传导干扰的方法。该方法采用HBYV非双绞2芯线作为干扰接收体,采用数字示波器记录干扰波形的最大幅值和单个脉冲的最大强度,通过与标准干扰发生器感应到HBYV非双绞2芯线上的干扰信号大小进行比较,确定干扰强度。以瞬变脉冲群干扰强度和浪涌干扰强度的测量为例,详细介绍了该方法的具体实现。     

一种反向递推正弦干扰观测器的设计方法

在多源干扰环境下,考虑一种基于输出信号的正弦干扰估计方法.引入低通滤波器激励干扰特性,得到一组级联关系的不可测信号,并将其分解为标准正弦虚拟干扰、等价有界干扰以及衰减项;在频率已知条件下,设计辅助滤波器,建立干扰频率与虚拟干扰之间关系,从而将外部正弦扰动表示为关于虚拟干扰的参数形式,利用虚拟干扰的估计值逐次降阶反推输入干扰.该干扰观测器设计方法独立于控制器结构,不需要估计等效干扰状态,可很大程度上降低计算复杂度.当不存在等价有界干扰时,这种反向递推方式可以渐近跟踪正弦干扰.在多源干扰环境下,通过调节辅助滤波器参数可以保证干扰误差动态一致最终有界特性.仿真和实验验证了该干扰观测结构的有效性.     

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。     

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.