自确认压力传感器结构参数设计及其有限元分析

设计了自确认压力传感器弹性体的结构参数,包括弹性体的材料选择,弹性体的形状、厚度和半径,建立了应变片在弹性体上的多组布片方案,为压力传感器实现自确认功能奠定了基础.应用有限元分析软件ANSYS对所设计的传感器弹性体进行了动、静态分析,获得了弹性体在受力情况下的位移、应力、应变分布状态,并且计算了弹性体的固有频率,分析结果表明,所设计的弹性体满足自确认压力传感器的设计要求.     

自确认压力传感器硬件平台设计

自确认压力传感器是一种不仅能输出压力测量值,并且能对其自身工作状态进行在线评估的新型压力传感器。系统利用TMS320F2812和TMS320C6713组成双处理器系统,完成对自确认压力传感器八路信号的同步采集和信号调理,然后利用DSP实现传感器的故障检测、诊断、自确认参数计算等复杂运算,将确认的测量值,测量值确认的不确定度,传感器状态输出给上位机或用户。实验结果表明,该系统实现了自确认压力传感器的各项功能,通过修改DSP软件部分,可以应用于其他传感器信号的数据采集与处理。     

多功能自确认传感器

提出了多功能自确认传感器.这种传感器具有多功能传感器和自确认传感器的特点,它可以检测多个物理量,对自身工作状态进行在线评估,并以给出测量值的不确定度;它具有故障自诊断功能,当发生故障时对输出数据进行重构,实现数据恢复.探讨了多功能自确认传感器的关键技术及发展方向,最后介绍了一种测量温度、湿度和甲烷气体浓度的多功能自确认...     

带管腔应变式压力传感器多自由度建模法

采用"共振峰提取"的方法对带管腔结构的平膜片应变式压力传感器建立了动态数学模型.利用传感器的时域校准数据得到了传感器的参数模型,进而求得了传感器的频率特性.实验结果和仿真计算表明,"共振峰提取"法在传感器动态模型建立方面有一定的工程应用价值.     

平膜片式薄膜压力传感器的线性度与灵敏度分析

针对薄膜应变片在圆平膜片上的两种基本布置方式，导出了平膜片式薄膜压力传感器的线性度和灵敏度的实用计算公式；分析了膜片的厚径比、薄膜应变比在膜片上的布置方式和位置对传器的线性度与灵敏度的影响，给出了部分研制的薄膜压力传感器的线性度和灵敏度的实测结果与理论计算结果的比较。     

自确认金属氧化物半导体气体传感器阵列及其应用研究

金属氧化物半导体(MOS)气体传感器阵列是机器嗅觉系统中获取目标气体信息的重要装置.由于气敏元件的材料特性,MOS气体传感器阵列在工作过程中不可避免地会发生突发故障及外界干扰,导致机器嗅觉系统的检测与分析性能下降.为了提升机器嗅觉系统的可靠性,在总结以往研究成果的基础上,提出了自确认MOS气体传感器阵列.该气体传感器阵列结合自确认传感器技术,能够实现自身的多故障检测与隔离、故障识别、故障恢复及测量质量评估等自确认功能.本文分别探讨了自确认MOS传感器阵列的硬件架构、功能模型及其关键技术.最后,介绍了一种面向大气环境污染气体监测的自确认MOS传感器阵列,实现了其异常状态监测与测量质量评估并对其有效性进行了验证.     

圆平膜片弹性特性分析与优化设计

针对圆平膜片在传统设计中存在的计算繁琐、效率低下和精度不高等缺陷,应用ANSYS建立圆平膜片有限元模型,并提出圆平膜片弹性特性分析与优化设计的方法. 该方法用ANSYS仿真分析周边固支圆平膜片的弹性特性以及弹性体应力和位移分布情况;通过对圆平膜片的应力、应变及其静态和动态特性的计算,研究弹性体结构尺寸参数和载荷对弹性特性的影响规律;通过对模型的优化设计,使圆平膜片的性能指标得到进一步优化,弹性元件的设计精度得到提高.该方法对于仪器仪表中圆平膜片的参数优化设计具有一定指导意义和实用价值.     

圆平膜片弹性特性的分析及其优化设计

针对圆平膜片在传统设计中存在的计算繁琐、效率低下和精度不高等缺陷,应用ANSYS建立圆平膜片有限元模型,并提出圆平膜片弹性特性分析与优化设计的方法. 该方法用ANSYS仿真分析周边固支圆平膜片的弹性特性以及弹性体应力和位移分布情况;通过对圆平膜片的应力、应变及其静态和动态特性的计算,研究弹性体结构尺寸参数和载荷对弹性特性的影响规律;通过对模型的优化设计,使圆平膜片的性能指标得到进一步优化,弹性元件的设计精度得到提高.该方法对于仪器仪表中圆平膜片的参数优化设计具有一定指导意义和实用价值.     

一种基于ARMA模型的自确认传感器结构

自确认传感器就是一种不仅能输出测量值,同时能够对自身的工作性能、状态进行在线评估的的新一代智能传感器。本文通过对传感器模型的分析,应用时间序列分析法,建立了一个比较系统的、完整的、基于ARMA模型的自确认传感器结构,进而对自确认传感器有一个更深层的认识。最后对自确认传感器技术作了一个简单的展望。     

焊接结构光纤Bragg光栅土压力传感器设计

针对传统土压力传感器长期稳定性差、抗电磁干扰能力不强以及组网难度大等问题,根据传感器与土介质的匹配原则,设计了一种焊接结构双膜片光纤Bragg光栅(FBG)温度自补偿土压力传感器,可实现温度和土压力2个参量的同时测量.传感器主要由2个膜片与基体组成,膜片与光栅固定柱一次成型,便于加工封装.对传感器灵敏度系数进行了计算分析.根据分析结果,加工封装传感器并对其进行了压力校准及温度自补偿性能实验.实验结果表明:传感器的输出波长分别与温度和压力呈线性关系,压力灵敏度系数为528.1 pm/MPa,输出分辨率为0.19%,线性相关度99.988%;在5~45℃内温度灵敏度系数为31.9 pm/℃,线性相关度99.998%,传感器在5~45℃范围内具有良好的温度自补偿能力,其性能参数符合工程应用要求.     

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     

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.     

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.     

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.