EMERSON推出高精度液体超声波流量计

艾默生过程控制于近日正式发布最新产品DanielTM3812液体超声波流量计。其具有计量可靠、维护简便、易于操作等特点,可广泛应用于石化、油品和水处理等行业。革命性的电子单元整合高级数字信号手段,使得DanielTM3812液体超声波流量计     

煤气计量仪表的分析

针对大管径、低流速、低压力煤气计量，在分析涡轮流量计、阿牛巴流量计、超声波流量计的测量原理、优缺点及运行情况基础上，说明了超声波流量计在煤气计量方面优势。结合工作实践，对超声波流量计在使用和调校过程中出现的问题提供了解决方法，超声波流量计在煤气计量方面得到成功应用。     

超声波流量计在高酸气田的应用

针对高含硫气田气相流量计应用现状,以及高级孔板阀存在计量偏差较大、五阀组解堵频繁、孔板清洗危险大及维护维修不便等缺点,介绍外夹式超声波流量计的优点及应用效果.     

DanielTM3818型高精度液体超声波流量计 艾默生过程控制有限公司

艾默生推出用于液化天然气高精度流量计量的DanielTM3818型液体超声波流量计。该流量计专为降低液化天然气流量计量的不确定度而设计,是海运及近海应用场合的理想选择,可用于贸易交接和财务结算计量、管线平衡、计量比对、分配计量以及轮船装卸等场合。利用DanielTM3818型液体超声波流量计对液化天然气进行动态流量计量可实现更高的精度,并且真正     

不理想条件下的水流量计量

采用以超声波液位计为核心的自动集、排气系统克服水气二相介质的影响；利用超声波流量计进行水中含有大量铁锈情况下的水流量计量；用插入式流量计进行不间断供水情况下的水流量计量。增加管衬克服管道锈蚀对计量的影响。     

超声波流量计与孔板流量计的比较

本文通过大量详实的理论推导、可信的应用实例，经过技术性能、现场安装使用、长期使用、经济性几个方面的比较详细论述了超声波流量计与孔板流量计的优劣。提出高压、大流量计量优先选用超声波流量计的建议。     

提高超声波流量计量精度的方法

时差法超声波流量计通过检测换能器发射和接收的超声波信号的传播时间信号,实现流量的计量。超声波换能器的谐振频率及超声波信号传播过程中相位和幅值的变化等因素,会影响对超声波信号到达时间的准确计量,从而影响流量测量的精度。准确计量超声波信号的到达时刻是提升时差法超生波流量计的计量精度的关键之一。针对换能器发射和接收超声波信号的处理和获取电路进行了设计和分析,得出了实验结果和实验数据,对实验结果给出了实验分析和结论,并通过软件算法给出了进一步提高测量精度的方法。     

超声波流量计在能源数据采集上的应用

济钢在能源中心(EMCC)中采用了超声波流量计作为水计量仪表,对全厂的水资源进行测量采集,实现水的有效利用和实时监控、平衡,减少能源浪费.该流量计采用超声波时差法测量介质流量,具有精度高、可靠性高、智能化等特点,另外,价格低及不停产在线安装是其最大的优势.详细介绍了EMCC系统中流量计的选用原则、超声波流量计的工作特点、安装调试中遇到的问题和解决方法、超声波流量计与能源中心监控平台的数据通信等情况.     

液体超声波流量计在海上原油贸易计量中的应用

介绍超声波流量计的测量原理,以及FPSO贸易交接计量仪表选型过程。     

GE检测控制技术助力中国荔湾深海气田项目

GE检测控制技术近日宣布赢得了中海油荔湾3-1深水项目的超声波流量计的项目,其旗下GF868火炬超声波流量计以其优异的性能、易于安装操作和维护的优势,在该项目上最终胜出。     

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.     

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。     

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.     

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。     

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     

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.