自动调零伺服倾角传感器的设计与实现

零位偏差和漂移是所有倾角传感器都待解决的技术难题.本文通过水泡尺旋转180°找平的古老方法深入研究传感器的调平原理,建立一套倾角传感器自动调零的理论和方法.采用步进电机和单片机控制技术设计实现自动调零伺服倾角传感器,很好的解决了零位偏差,时间漂移和温度漂移等问题,使倾角传感器的性能得到提高,具有非常重要的应用价值.     

MCS-51单片机控制的自动校零接口电路

为提高仪表精度,消除零位漂移,笔者选用了由单片机控制的自动校零接口电路。文中论述了自动校零电路的设计和工作原理及如何采用程序控制的数字式自动调零对正负零漂自动校零。该校零电路在仪器、仪表的自动化测试中提高了测量数据的准确性、性能稳定可靠。     

瓦斯探测器零点校正技术的研究

针对目前广泛使用的瓦斯探测器漂移大、成本高、维护周期短等问题,提出了基于恒温控制电路的瓦斯探测器的定时自动零点校正方法。该方法以催化燃烧式气体传感器为对象,采用恒温控制电路为传感器供电,以零点漂移的理论分析和大量实验研究工作为依据,解决了该类探测器长期未能解决的零点稳定性问题。采用模拟电子开关配合电阻网络实现数字电位器设计,节约了成本。实验结果表明:采用恒温控制电路的零点校正后的残留偏差比未经校正的输出值减少了近1个数量级,为设计具有自动定时调零功能的瓦斯探测器提供了技术支持。     

厚度传感器接口电路中自动换挡及调零技术

自动换挡和自动调零是传感器接口电路的关键技术,它直接影响到测量过程中的测量分辨率、精度和误差,如果解决好这个问题就能对信号采集、处理起到决定性作用.本文介绍了厚度传感器信号采集电路的自动换挡和自动调零技术.     

一种自动调零应变信号调理器的设计

使用电阻应变片测量物体的承受载荷情况是最常用的测量方法。受电阻应变片个体操作差异性、传输线路损耗、温度漂移等因素的影响,初始零位的固定对实际测量数据的读取有重要的意义。基于STM32微控制器,配合多种电子元器件,设计出了一种具有自动调零能力的应变信号调理电路,完全实现了自动化,方便快捷,提高了调零精度。     

基于数字电位器的电子水平仪自动调零方法

零点漂移是所有传感仪表都必须考虑的一个问题,本文基于所设计的电子水平仪,提出了一种用单片机控制数字电位器实现水平仪自动调零的方法,并给出了硬件设计电路和软件控制流程。实验表明该方法能够快速有效地实现仪表系统的自动调零。     

基于数字电位器的电子水平仪自动调零方法

零点漂移是所有传感仪表都必须考虑的一个问题,本文基于所设计的电子水平仪,提出了一种用单片机控制数字电位器实现水平仪自动调零的方法,并给出了硬件设计电路和软件控制流程.实验表明该方法能够快速有效地实现仪表系统的自动调零.     

用8031单片机解决电桥的零漂问题

本文介绍了用8031单片机对电桥作周期性的自动调零，克服了系统因温度等因素引起漂移所造成的误差，大大提高系统测量精度。     

基于数字调节方法的MEMS陀螺零位补偿技术研究

针对环境温度影响导致MEMS陀螺零位输出变化较大的问题,设计了一种基于数字调节方法的零位补偿电路并提出了一种陀螺零位漂移特性的测试方法。该补偿电路依据陀螺内部温度传感器输出,实时调节补偿电路输出,实现零位补偿。采用全温(-40℃～+60℃)测试方法,研究得到陀螺零位漂移模型,再经过研究零漂值与补偿电路值之间的对应关系,求解出温度与补偿电路之间的数学模型。实验表明,采用该方法使陀螺零位在全温范围内稳定精度提高了一个数量级,证明了提出方法的可行性和有效性。     

数据手套中智能化数据处理技术的研究

该文针对数据手套应用过程中出现的布置在手套上传感器的零位、测量范围易变;从传感器获取的数据波动大;手套固有的动作牵连,引起的传感器输出耦合;动作的智能判断;非线性修正等问题,进行了深入的研究。提出了自动调零和调幅中的软硬件结合方法;行之有效的数据的预处理技术;传感器数据的实时解耦;手势的智能判断等相应的解决方法,满意地解决了数据手套应用中的各种问题。     

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.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.     

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.     

Call for papers Special issue on Modeling and control technologies for civil,energy,and power systems

正The control of civil,energy,and power systems presents significant new challenges for modeling and control theory.The purpose of this special issue is to provide a forum for researchers and practical engineers to discuss the recent advances in modeling and control technology development for civil,energy,and power systems.Prospective authors are invited to submit their original contributions with the focus on theory or applications of modeling,control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate and promote academic exchange between Chinese and foreign scientists everywhere.