基于分布式温度监测的大空间半导体制冷系统

针对装甲车辆驾驶舱温度调节的迫切需求,对基于半导体制冷的大空间温度调节装置进行试验研究。设计了大空间试验箱、半导体制冷系统和基于分布式传感器的温度监测系统。选择不同类型的制冷片,使其工作在不同电流工况和散热条件下,得到了制冷片两端的温差与箱体内平均温度随制冷片工作时间的变化。结果表明:温度监测系统能够实时采集显示半导体制冷片冷热端与箱体内温度的变化情况;制冷片和制冷片工作电流的选择要与制冷系统的散热强度相适应才能达到良好的制冷效果;适当增加制冷片冷端的散冷能力,有助于降低制冷片两端的温差,提高制冷效果。     

基于最大制冷系数调节算法的井下制冷器设计

为了提高井下电子仪器的应用温度范围,创新性地设计了基于半导体制冷技术的井下制冷器为仪器降温。通过分析半导体制冷片的性能特性,得到了最大制冷系数工况的实现条件,据此设计了能够均衡最大制冷系数工况和最大制冷量工况的分段调节控温算法,以达到高效制冷的目标。为了实现控温算法的系统设计,使用微控制器控制高精度温度传感器采集多点温度,同时用特殊功率运算放大器设计了精密电压-电流转换器为半导体制冷片供电。仿真及实验测量结果表明,该井下制冷器具有制冷效率高、自产热低、可耐高温等特点,使较低温度级别的井下电子仪器在较高的环境温度下能够正常工作,有利于降低钻井成本。     

半导体制冷技术及应用路径研究

半导体制冷技术也称为热电制冷技术,是广泛应用于空调制冷、电池散热等领域的新型制冷技术,与传统制冷技术相比,半导体制冷能够有效调整温度,提升元器件的使用效率,增强制冷装置的可靠性与实效性,并使制冷变面积呈现出最大化、最优化的应用特征。本文结合半导体制冷的原理,探析半导体制冷特点及方式,提出相应的应用路径。     

半导体制冷应用二例

半导体制冷又称热电制冷或温差制冷,是利用特殊的半导体材料通过直流电时产生低温的一种制冷方式,在生活中应用广泛。如:小冷藏箱/柜、冷热座垫、冷饮水机、空调机、冷热床/枕/帽、冷冻治疗器、冷探针等。本文以半导体小冰箱(冷热两用)、冷饮水机二例产品的制作加以介绍。     

多功能光伏书包的设计

考虑到目前户外旅行是一个热门的趋势,户外旅行者需要更先进的户外装备,因此设计了一个多功能太阳能书包,实现制冷、制热、制水和供电等功能。本装置基于光伏发电和热电制冷的原理设计而成,由太阳能电池板、导线、半导体制冷片、USB接口、开关、水杯、圆形磁铁组成。太阳能电池板在光下利用半导体的光电效应生成直流电,电流再通过导线分别通向半导体制冷片和USB接口。当开关闭合后,利用半导体材料的帕尔帖效应,当直流电通过两种不同半导体材料串联成的电偶时,在电偶的两端即可分别吸收热量和放出热量,可以实现制冷或者制热的目的。将半导体制冷片通过圆形磁铁固定在水杯上,通电之后产生制冷效应,将空气温度降低到露点温度以下,使得空气中的水蒸气凝结为小水滴,以达到制水的效果。     

基于半导体制冷器件的小型温度控制系统

本文介绍了基于半导体制冷器件的小型温度控制系统的设计思想以及实现方法。重点研究了半导体制冷器件的基本原理、系统构成、以及PID控制方法的单片机（SCM）实现。系统经实际测试,温度可在-2．5℃到60℃范围内设定,设定精度0．1℃,超调量不超过2℃,稳定后最大波动0．5℃以下。采用此方法设计的小型温度控制系统摒弃了传统使用压缩机的制冷技术而采用半导体制冷器件,因而具有控制灵活,控制精度高的优点,并显著降低了成本。能够满足生物、医学以及一些工业领域对小型恒温箱的要求,具有一定的推广应用价值和市场前景。     

小型温控系统的研究

本文介绍了基于ADuC841单片机和半导体加热制冷片的小型温度控制系统设计.本设计采用半导体加热制冷片作为温度控制的执行部件,温度传感器DS18B20进行温度检测并提供反馈信号,在控制器单片机上实现增量式PID控制算法.本设计的应用为实现快速、精确的小型温度控制系统提供了一种体积小、功耗低、经济有效的解决方案.     

基于半导体制冷技术的恒温控制仿真

基于半导体制冷技术,针对航天、军事、医疗、生物制品、车载等特殊有限工作空间的独特需求,设计了体积小、成本低、性能高、结构合理紧凑、功耗低且节能环保的微型半导体温控箱箱体,并对温控箱的温度及变化速率等各种参数能够实时精确控制,为高性能生物制剂、功能材料等的实验室制备方法以及性能研究提供技术支撑。本文选用TEC-12706半导体制冷片并进行了半导体制冷原理进行验证实验。半导体恒温箱采用强制对流方式,提高了储藏室空气之间的热交换率,由此在距离储藏室内胆一定距离的三维空间区域形成一个恒温控制区,该区域内温度均匀无差异,且能迅速响应半导体片的温度切换。仿真表明,该系统具有结构简单、控制精度高、可靠性好、性能稳定等优点,具有广泛的应用前景。     

智能降温——捷波坚鸟96智冷版显卡

捷波坚鸟96智冷版显卡采用了ATI Radeon 9600移动版的显示核心，核心／显存频率为325MHz／440MH2，容量为64MB，位宽为128bit。最特别的是该显卡采用了半导体制冷技术，通过CPU和散热片之间的一块制冷片，利用半导体珀尔帖效应，可迅速地将制冷片一端的温度降至零下10℃以下，以达到制冷的效果。     

冰箱制冷速度检测系统

描述了一种实现对４８台冰箱冷冻，冷藏室温度及对变化情况进行连续８ｈ检测的系统。本系统利用抗干扰能力强，适合于工业现场等恶劣环境下工作ＳＴＤ总线工业控制机作为主机，以温度稳定性高，电阻－温度关系线性度好的铂电阻作为温度传感器，将温度转换成相应的大小的阻值，并由不平衡电桥转换成电压，经Ａ／Ｄ转换后送入工控机。由于软件进行温度的检测，并进而分析冰箱的制冷效果、制冷速度、开停机时间、次数等技术指标。为输入     

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.