一种典型实用的铂热电阻测温电路

本介绍了作设计的一种以铂热电阻作为一次测温元件的具有电压输出的温度变换器。从而实现由检测出铂电阻上的电压值来定量计算真实温度。     

基于铂热电阻测温系统设计

铂热电阻信号调理器ADT70可以将因温度变化引起的铂热电阻的电阻变化转换成电压信号.采用ADT70设计了一个8通道测温系统.该系统由ADT70、单片机MSP430F149、存储器、显示、接口等组成,采用普通的薄膜式铂热电阻就可以测量-50℃～+200℃的温度范围.     

铂热电阻线性化电路的研究

本文作者根据对铂热电阻的R_t-t特性的数学分析,设计出简单的数学模型,并据此进行电路设计,使电路的输出电压与温度成线性关系。实验证明,这种电路在测温范围为-100～500℃时,实现了铂热电阻的非线性校正。电路结构简单,成本低,能满足中等精度测量仪的要求。     

高精度数字多用表在铂热电阻测温中的应用

高精度数字多用表（61/2位以上）具有显示直观、操作简单、携带方便等优点,自上世纪90年代以来,在铂热电阻测温中得到越来越广泛的应用.     

一种实用铂热电阻测温电路

针对铂热电阻传感器测量温度,采用普通稳压源桥式电路而产生非线性误差的问题,运用集成运算放大器工作在线性区域的特性,将恒流源原理应用到测温桥式电路中,并采用集成A/D转换技术的单片机Mega16,通过运算消除了非线性误差,实现了对温度的精确测量.试验结果表明,应用此种测温电路,缩短了单片机计算时同,一定程度上缓解了变送滞后对测量精度的影响,同时降低了误差.     

铂热电阻温度传感器非线性校正方法与电路设计

介绍铂电阻温度传感器非线性补偿的一种方法。给出铂电阻线性测温的设计原理和实际电路，运用数字原理对铂热电阻测温电路进行研究，为铂热电阻的非线性补偿方法提供理论依据。     

工业铂热电阻的精密数字测温

采用工业铂热电阻、DT-1000型数字万用表等普通零部件,按独特的非线性处理方法改装后,既实现了在中温温区的精密数字测温,还保留着数表原有的全部功能。实验结果表明,该方法能更好地实现非线性校正,且拟合精度高,测温准确度达到±0.1℃。     

热电阻测温的计算机校正方法

本文提出了一种基于IPC610工控机的铂热电阻自动测温校正系统,根据被测温度的解析解,将温度信号的A/D转换值直接代入求得被测温度,从而克服铂热电阻的非线性,该系统具有现场校正的功能,可消除电源电压,扩大电路及引线电阻等对测量精度的影响,可以扩大测量范围。     

四线制检测法测量热电阻的测温原理探究

文章从四线制检测法测量热电阻的电路原理入手,通过建立电路模型的方式,对其测温原理展开研究,并对使用该检测法检测三线制和四线制热电阻时为何能消除热电阻内部引线电阻影响,而检测两线制热电阻时却不能消除该影响的原因进行了详细阐述。     

An Analysis of the Possibilities of Modern Methods of Measuring the Efficiency of Thermoelectric Elements and Their Realization

Modern methods of measuring the efficiency parameter – the basic criterion for estimating the quality of thermoelectric elements – are considered. An analysis of the classical Harman method and its modified version is given as well as of the test method of analyzing the transient characteristic. The last two methods are carried out using the ZRTM measurement system software package. Results of tests of thermoelectric elements are presented in detail.     

从茶具材质发展论产品设计的实用性

实用性是任何成功产品必须的要求,而材质的选取则是构成产品的物质依归.从中国茶具材质的发展历程出发,通过对茶具材质实用性的分析论证了材质在产品设计实用性中所起到的重要影响和作用,同时揭示出在着重考虑材质的优选之外,影响产品设计实用性的因素还与外形结构、制作工艺等物质技术条件以及绿色环保和以人为本的思想密切相关.研究有助于在产品设计中对产品实用性的多角度思考.     

Revealing the Enhanced Thermoelectric Properties of Controllably Doped Donor-Acceptor Copolymer: The Impact of Regioregularity

Albeit considerable attention to the fast-developing organic thermoelectric (OTE) materials due to their flexibility and non-toxic features, it is still challenging to design an OTE polymer with superior thermoelectric properties. In this work, two “isomorphic” donor–acceptor (D–A) conjugated polymers are studied as the semiconductor in OTE devices, revealing for the first time the internal mechanism of regioregularity on thermoelectric performances in D–A type polymers. A higher molecular structure regularity can lead to higher crystalline order and mobility, higher doping efficiency, order of energy state, and thermoelectric (TE) performance. As a result, the regioregular P2F exhibits a maximum power factor (PF) of up to 113.27 µW m⁻¹ K⁻², more than three times that of the regiorandom PRF (35.35 µW m⁻¹ K⁻²). However, the regular backbone also implies lower miscibility with a dopant, negatively affecting TE performance. Therefore, the trade-off between doping efficiency and miscibility plays a vital role in OTE materials, and this work sheds light on the molecular design strategy of OTE polymers with state-of-the-art performances.     

紫外线(UV)固化技术在数字成像材料中的应用(二)UV固化技术在印刷电路版数字化制作中的应用

近年来,数字成像技术不断提高和应用范围的迅速推广,也推动了UV固化技术在这一领域的融合和应用,取得了极大的成效,由于UV固化材料具有快速固化、高效、低污染、节能、优质等特点,很快发展成为一种新型的数字成像材料,目前已实现产业化的主要有UV喷墨打印、印刷电路版数字化制作、计算机直接制版CTP、立体光刻等四种技术,作者拟分为四个专题予以阐述,本文主要讨论其第二个专题：UV固化技术在印刷电路版数字化制作中的应用.     

An Inverse Approach to Determine the Mechanical Properties of Elastoplastic Materials Using Indentation Tests

In this work, an inverse approach based on depth-sensing instrumented indentation tests is proposed to determine the Young's modulus, yield strength and strain hardening exponent of the materials for which the elastoplastic part of the stress-strain curve can be described using a power function. Numerical verifications performed on typical engineering metals demonstrate the effectiveness of the new method. The sensitivity of the method to data noise and some experimental uncertainties are also discussed, which may provide useful information for the application of the method in practice.     

一种基于实例推理的钢铁产品成本估算方法

针对钢铁企业生产过程复杂和现有定制产品的成本估算方法存在的缺陷和不足,提出了基于实例推理技术的钢铁产品成本估算方法,分析了钢铁产品生产流程,据此认定了钢铁产品生产过程中的各项作业。详细阐述了实例库中实例的描述方法和实例库的组织结构,给出了实例匹配检索算法、实例调整和学习评价,并以在某钢铁企业的实际工程应用进行了验证说明。     

串并联电爆网路的准爆验算与优化设计

在分析串联雷管准爆试验贡线的基础上，提出了简化的串联雷管准爆条件，建立了串并联爆破网路的准爆验算公式，给出了爆破网路优化的计算机方法。     

An Economic Approach to the Management of High‐Quality Processes

Modern manufacturing developments have forced researchers to investigate alternative quality control techniques for high‐quality processes. The cumulative count of conforming (CCC) control chart is a powerful alternative approach for monitoring high‐quality processes for which traditional control charts are inadequate. This study develops a mathematical model for the economic design of the CCC control chart and presents an application of the proposed model. On the basis of the results of the application, the economic and classical CCC control chart designs of the CCC control chart are compared. The optimal design parameters for different defective fractions are tabulated, and a sensitivity analysis of the model is presented for the CCC control chart user to determine the optimal economic design parameters and minimum hourly costs for one production run according to different defective fractions, cost, time, and process parameters. Copyright © 2012 John Wiley & Sons, Ltd.     

An Approach to Quantify the Factors That Affect Performance Measurement System Implementation

Although there have been many important academic advancements in the area of performance measurement systems, many practitioners and researchers still report encountering significant challenges during practical applications. This has led to the development of research to identify factors that affect the success of performance measurement systems. Previous studies attempt to identify and evaluate these factors, but there is little evidence of the inter-relationships and overall effects of various factors on the successful implementation of performance measurement systems. This article describes an exploratory study that applies an existing approach, originally proposed to design performance measurement systems, to investigate the effectiveness of the approach in quantifying the systemic effects of success factors on the implementation of a performance measurement system. The results of this study suggest that applying this approach provides quantitative assessments of the systemic effects of the success factors, which can be used to design more robust implementation strategies.     

An Implementation of the Scheffé Approach to Calibration Using Spline Functions,Illustrated by a Pressure-Volume Calibration

This article presents an implementation of a Scheffé-type calibration procedure to the pressure-volume relationship for nuclear-materials processing tanks. We use splines (piecewise poly-nomials) to fit this relationship and present a comparison between the propagation of error and the Scheffé formulation of statistical uncertainties. An ASCII FORTRAN program and user's manual are available for performing the analysis. The recommended procedure is demonstrated on tank data collected by the National Bureau of Standards.