一种新的校正铂电阻传感器非线性的数学方法

提出了一种新的校正铂电阻传感器非线性输出的数学方法———函数变换法,在讨论校正传感器非线性基本数学原理基础上导出了线性化条件的解析式。为检验理论的正确性,研究了铂电阻温度计非线性校正的问题,并设计了一个新原理的铂电阻信号调理电路。实验证明:在-200～650℃范围内,测温误差小于0.86℃。从数学原理上讲,这种方法可适用于其它传感器非线性输出的校正。     

用A/D转换器实现铂电阻温度计的非线性校正

针对铂电阻传感器的非线性校正,一般需要另加一个特别校正电路的问题;提出了在测量温度的应用中利用A/D转换器作非线性转换,实现铂电阻传感器的非线性校正;同时将输入信号的一部分送到A/D转换电路的基准电压端,并恰当地选择A/D转换电路的设计参数的方法,使铂电阻传感器在用于-15～200℃范围的温度测量时的非线性误差不超过0.01℃.这样既简化了电路设计,又有效提高了铂电阻测量温度的精度.     

铂电阻测温电路的线性化设计

介绍一种基于A/D转换原理的铂电阻测温的非线性校正方法,给出了铂电阻线性测温的设计原理、实际电路以及试验数据.     

铂电阻的高精确度非线性校正

详细分析了铂电阻非线性校正的原理,通过图形分析及函数变换,推导出一套实用的计算公式。另对分段补偿的原理及试探逼近法也作了介绍。非线性校正精确度达到:单段校正为ε<±0.00073℃(0～100℃)或ε≤±0.006℃(0～200℃);四段校正为ε<±0.001℃(0～200℃)或ε<±0.0241℃(0～650℃)。     

高精度铂电阻测温非线性校正方法

介绍了铂电阻测温非线性校正方法.该方法不是采用传统方法,而采用对象非线性特性函数的对称函数作为校正函数.利用该方法,能有效提高铂电阻测温精度.     

铂电阻测温电路的线性化设计方法

介绍一种基于A／D转换原理的铂电阻测温的非线性校正方法，分析了铂电阻线性测温的原理，并给出了A／D转换器7135与单片机89C51接口电路及试验数据。     

基于RBF神经网络的传感器非线性误差校正方法

介绍了利用人工神经网络进行传感器非线性误差校正的原理。提出了传感器非线性误差校正的径向基函数(RBF)神经网络方法,并与采用BP神经网络校正非线性误差进行了比较。最后给出了一个仿真实验,实验结果表明:采用RBF神经网络可以明显提高网络收敛速度,大大减小传感器非线性误差,校正效果优于BP神经网络。     

温度传感器在无人飞行器控制系统中的应用

分析了飞行控制器系统采用的2种温度传感器工作原理,探讨了铂电阻传感器非线性校正的硬件和软件实现方法,并设计了相应的测温电路。2种温度传感器均具有体积小、电路结构简单、调试方便、测温范围宽、高可靠性和易使用等优点。试验结果表明:2种温度传感器均能够很好地满足无人飞行器对较低环境温度及时做出反应的要求,提高了无人飞行器执行任务时的可靠性和安全性。     

高精度,通用型温度传感器的非线性校正电路

一、引言目前,数字式温度显示仪表的非线性校正方法很多,概括起来可分为下列三种:一是在A/D转换之前的模拟信号变换过程中将信号进行非线性校正,这种方法称为模拟非线性校正;二是在A/D转换过程中进行校正;三是A/D转换之后的数字部分进行校正,校正后再进行计数显示。采用上述三种方法进行非线性校正,其校正精度常常低于0.1%,且通用性差,不能同时对多种型号温度传感器的非线性实现校正,对不同型号传感器,需设置不同的校正电路或改变电路参数,从而给仪表制造与使用带来诸多不便,为此,设计一种精度更高、通用性强、成本低的非线性校正电路很有必要,也是仪表设计必须考虑的一个重要问题。笔者设计了一种校正精度高于0.05%,可配接不同型号温度传感器的通用型非线性校正电路,且成本低,调试方便,工作稳定可靠。     

基于神经网络的传感器非线性误差校正

介绍了用神经网络校正传感器系统非线性误差的原理和方法,提出了一种基于RBF神经网络的传感器非线性校正模型及其算法,并与采用BP神经网络校正非线性误差进行了比较,并给出一个仿真实验,实验结果表明:采用RBF神经网络的传感器非线性校正精度和网络训练速度均大大优于BP神经网络,能满足实用要求.     

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。     

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.     

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.     

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     

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.     

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.     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.