拉-压力传感器线性度的有限元分析

采用有限元法对应变式拉压力传感器弹性元件进行分析。用此法不仅可以得到弹性元件的应变分布特性 ,确定最大应变区的位置 ,而且可以得到力与应变的一元线性回归方程 ,分析出传感器的线性度。分析结果表明 ,此传感器的线性度很好 ,能满足使用要求。用实验方法对此进行了验证 ,结果表明 ,有限元法是传感器结构分析的有效工具     

微形变腕力传感器

介绍了一种新型机器人六维腕力传感器.采用了激光干涉法测量由外力施加在弹性元件上产生的由微形变产生的微位移测量原理,使得弹性梁的设计空间更大.特别是传感器动态特性得到了提高.本文详细讨论了弹性元件的设计,包括通过有限元方法对这种弹性元件的定量计算.对于弹性元件形变的检测也是本文的讨论重点.通过激光干涉的方法,传感器的灵敏度得到提高,同时,本文还详细讨论了六维力分别施加于弹性元件时对激光干涉的作用.     

压导管机床专用力传感器开发与研制

根据汽车发动机压导管专机开发研制的工作要求，从机床设计具体结构考虑，需要设计专用圆柱式电阻应变力传感器为机床的控制系统提供压力数据信号。圆柱式电阻应变力传感器的设计重点在于弹性元件的设计。本文对弹性元件进行了结构设计之后，采用弹性力学变分法和有限单元法对弹性元件进行应力应变分析，两种方法计算结果相吻合，最后对弹性元件进行了强度和寿命校验。这些设计计算成果为该传感器生产商的研制和生产提供了理论依据，也可供同类型力传感器的设计计算借鉴。     

温度补偿的FBG式飞机驾驶杆力传感器

在理论分析飞机驾驶杆弹性元件受力后应变分布特征的基础上,设计了基于光纤布拉格光栅（FBG）的宽温度范围杆力传感器。在30℃～80℃温度范围内,通过对飞机驾驶杆弹性元件施加横向和纵向载荷,实验研究了基于FBG的宽温度范围飞机驾驶杆力传感器的响应特性。实验结果表明,该传感器的纵向和横向灵敏度分别为4.74pm/N和5.16pm/N,纵向和横向灵敏度的温度补偿误差分别为0.76%和0.54%。     

轴向力在线监控装置弹性元件的有限元分析

对离心式旋转机械轴向力在线监控装置做了简单的介绍,此装置包括测力弹性元件和轴向力在线监控 系统两部分,为了保证所研制的测力传感器的性能,采用有限元方法计算了弹性元件在轴向力 Ｆ＝ ３９．２ ｋＮ时 的应变、应力、灵敏度及轴位移的分布情况,结果表明：所设计的测力传感器完全符合要求。     

仿生湿吸二维微力传感器设计与试验研究

设计了一种L型的二维微力传感器,该二维微力传感器采用悬臂梁式结构。在弹性力学和材料力学基础上,利用Solidworks三维建模软件和ANSYS仿真软件对传感器分别进行模型建立和有限元应变分析。对该二维微力传感器的实体进行标定,得出了力和输出电压之间的关系。然后,在设计与分析二维微力传感器的基础上,研制了二维微力传感器阵列测试系统。最后,在测试系统实施了不同预压力下的湿吸力测试试验,验证了传感器和系统的可靠性。     

高精度传感器弹性元件应变梯度的非线性误差分析

定量地分析了弹性元件应变梯度产生的非线性误差，通过分析计算表明弹性元件粘贴区的应变梯度是应变式高精度传感器非线性误差产生的主要因素之一。     

平行梁式荷重传感器设计与计算

本文介绍一种平行梁式传感器的设计计算和弹性元件的受力分析。文中分别对两种结构类型的传感器弹性元件进行内力分析和计算,并用光弹性实验观察应力分布来计算各测量点的应变值。数据表明,其设计计算理论是比较符合实际的,在生产实践中将会得到广泛使用。     

轮辐结构的联轴器式扭矩传感器研究

针对现有动态扭矩传感器使用不便的问题,设计了一种轮辐结构的联轴器式扭矩传感器,给出了总体设计方案和结构图,对传感器的弹性元件进行应力分析,得出了应力与扭矩的计算方程,确定了弹性元件材料和加工工艺,并对传感器样品进行了静态标定,经实际测试表明:该传感器的线性度为0.55%,滞后为0.54%,灵敏度为1.0195 mV/V。     

基片式光纤光栅传感器应变传递分析与试验

为研究基片式光纤光栅传感器传递效率,建立了应变传递模型,对基片式光纤光栅传感器与裸贴式光纤光栅传感器进行了对比试验,得到了传感器中心波长与挠度关系曲线,试验结果表明：基片式光纤光栅具有良好的线性度,应变灵敏度为0.822 pm/10－6,应变传递效率可达89.4%。利用ANSYS有限元软件对基片式光纤光栅传感器进行应变传递分析,有限元分析结果与试验结果一致,证明了模型和计算方法的有效。提出铍青铜基片式封装形式,并建立ANSYS模型,对其传递效率进行计算,计算结果表明：铍青铜封装应变传递性能一般,但对光纤光栅具有良好的防护性能。     

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.     

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.     

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.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

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。