基于超声波测距的塔吊防碰撞探测器设计

针对塔吊作业防碰撞问题,设计了用于障碍物检测的防碰撞探测器.基于超声波测距原理,探测器可以对接近塔吊臂的障碍物主动检测,发出报警信息.从系统的构成、工作方式、探测器结构设计和安装布置等几方面进行了详细论述,通过Matlab仿真对设计结果进行了验证.该设计扩宽了探测器检测范围,通过多节点布置,对塔吊臂形成了封闭的三维保护区,有效避免事故发生,对于塔吊安全运行具有重要意义.     

一种家用天然气阀门状态监测装置的设计

本文提出一种家用天然气阀门状态监测装置,整个装置由控制模块、电源模块、报警模块和采集模块等多部分组成.利用这些模块组成的天然气阀门状态监测装置,可以实时地监测家用天然气阀门的状态,从而提醒天然气使用人员及时关闭天然气阀门,以便更安全科学地使用天然气.该方案具有安装简单、不需要改动现有管道结构、不需要外接电源等优点.     

可靠适用的温度控制器

本控制器用于自制家用电热水器的控制。目前市场上出售的家用电热水器虽然性能日趋完善,但都有一个共同的缺点,即用过之后仍保留一箱热水暂时用不上。电子爱好者不妨自己动手做一个家用电热水器,不但解决了这个问题,而且由于本电路具有防干烧、水位指示、恒温及漏电自动切断电源等功能因此使用起来安全感倍增。     

基于GSM网络的家用报警机器人

介绍了一种基于GSM通信网络的家用报警机器人,论述了该机器人系统的工作原理及软硬件设计。该系统采用Motorola68HC11微处理器以及GSM网络模块,利用电话和SMS短消息功能,以简单可靠的方式对家用报警机器人进行远程监测和控制,实现了防盗、防火、防煤气泄漏与防漏水等检测报警功能。     

产品大剖析

ADF-2100系列数字式张力探测器;AS-1962-1102B无线防宠防下潜红外探测器;RK815DT反遮掩探测器;AX-70TN／AX-130TN,AX-200TN红外对探测器;T2（015N）雷霆铁血警卫;FC-300无线报警主机;DG483优雅型移动探测器;ED690智能双鉴探测器;     

新品速递

两欺家用无线一体电脑 生活就该简单些 一体电脑相比传统台式电脑最大的优势就是简单——将主机和显示器融为一体．在移动和使用时省去了很多麻烦。如果从这个角度出发．那么采用无线键盘鼠标,支持无线网络就应该成为家用一体电脑的标配。     

微型金属探测器

本文推荐一款微型金属探测装置的设计。您只需花很少钱和几个休息日,就能成为一台小巧的腕式微型金属探测装置的主人。为您的考古、探宝活动增添一个好助手。上世纪60～70年代,使用差频原理(B.F.O)的金属探测装置应用十分普遍。在第一台商用探测器出现后不久,某些型号的金属探测器销量增加了上千倍。后来,由于性能更好的感应平衡(I.B)和脉冲感应(P.I)型金属探测器在市场上出现,差频式金属探测器很快就不再流行了。但是,采用差频原理的金属探测器在成本低和结构简单方面具有其他形式的金属探测器无法相比的优点,所以很适合于     

浅谈无线被动红外探测器

作者从无线被动红外探测器的探测与传输的稳定性、探测器功耗和防破坏性能三方面来解析了无线被动红外探测器的技术运用。     

戴尔VOSTRO成就330商用多功能一体机：成就新商用

对于一体机,很多人的印象还停留在家用一体机之上。确实,家用一体机更容易被普通用户接受,使用起来也确实方便简单厂许多。不过对于商用一体机,了解的人就相对较少了,大家对于商用机的印象依然停留在黑色的机箱、显示器和键鼠的阶段。     

选煤厂带式输送机防伤人安全保护系统设计

针对现有选煤厂带式输送机保护装置缺少动态防伤人监测功能,输送机旋转部位易导致伤人事故等问题,提出一种选煤厂带式输送机防伤人安全保护系统设计方案;介绍了该系统的总体设计方案、设备选型、探测器布置方式。该系统通过热释放红外探测器、对射红外探测器及红外电子网检测人体靠近输送机旋转部件的情况,当工作人员进入检测区域活动时给予提示、报警或进行停机保护。现场工业试验结果显示,选煤厂带式输送机防伤人安全保护系统可有效预防带式输送机旋转部件伤人事故。     

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.