基于B/S结构的企业远程实时测控系统

介绍了一种新型的基于B／S结构的生产企业远程实时测控和数据发布方法，给出了一个由web服务器、应用服务器、实时数据库服务器、嵌入式Web服务器和ActiveX通讯插件组成的自来水厂实时监控模型，详细介绍了嵌入式Web服务器设计方案及能够提高系统实时性能的ActiveX通信插件的设计方法。     

数据库访问方法

当今的Web数据库开发工具提供了通过一个浏览器对一个公司数据库进行访问的多种策略，Web化的快速应用程序开发RAD方案可以通过利用插件或ActiveX控件在您的浏览器中实现。结合ActiveX或Java技术的HTML语言是数据库设计的最典型的方式，而纯HTML语言所提供的客户方的功能范围有限，一些工具为您的应用程序开发提供了诸多选项。     

基于指标结构基因模型的评价驱动型产品设计

针对产品方案设计中用户反馈信息处理、转化问题,提出了交互式产品设计方法,建立了以用户交互式评价为核心的"指标-结构-基因"产品设计模型。该模型应用模糊集与粗糙集理论处理用户评价信息;利用灰色系统理论,应用层次分析法建立评价指标体系,实现由指标体系到产品结构的转换;采用遗传算法,通过产品结构基因编码,根据用户交互式评价,获得产品进化设计方案。以某企业婴儿手推车产品方案设计为例,阐述了应用该方法进行产品方案设计的一般步骤。     

虚拟企业下基于Web的三维协同设计研究

产品的三维模型是虚拟企业中各方人员组成的多功能团队进行产品协同设计的关键，采用Web技术以及当前流行的三维设计软件Pro/Engineer，对设计人员（包括客户)在虚拟企业环境下进行异地实时设计和装配作了探讨，提出一个软件框架模型，并初步规划了协同设计的过程，得到一些有意义的结论。     

基于Web的交互式三维建模

OpenGL作为一个性能优越的图形应用程序设计界面(API),适用于广泛的计算机环境,可实现高性能的三维图形功能,被认为是高性能图形和交互式场景处理的标准。随着Internet的迅猛发展,Web已经成为世界范围内最大和最有效的信息获取和发布媒体。ActiveX控件是一个在Internet上自动传送的可执行程序,通常在浏览器中运行,运行速度快,功能强大。本文详述了使用ActiveX控件和OpenGL相结合的方法从而实现基于Web的交互式三维建模。     

Web环境下基于Brower／Server模式的工艺卡片设计系统研究

本文介绍一个在Web环境下，利用ASP/ADO技术和ActiveX控件技术开发基于Brower/Server方式的工艺卡片设计系统的基本原理和功能特点，并讨论了工艺文件模型的表达方法和工艺数据库的建立、基于Web的工艺卡片信息集成与输出等关键技术，最后用一个实例来描述工艺设计过程，验证了本文所提出的思想。     

基于客户定制的产品配置

为了给客户提供一个直观和可视化的产品配置工具,研究了基于客户定制的产品配置模型,包括产品族功能模型、产品族装配模型以及产品配置知识的表达模型.利用该模型构建了一种面向客户基于Web的虚拟产品定制和展示环境,使得用户在该环境下可以提交需求目标,系统根据用户的需求进行配置,生成的产品三维实体模型可在浏览器中动态地观察和操作.     

ASP技术应用：用ASP技术得到主页被访问次数的三种方法

ASP是Microsoft Active Server Pages的缩写,即动态服务器主页。它是服务器端脚本编写环境,在Web服务器上解释脚本,可以组合HTML页、脚本命令和ActiveX组件来创建动态、交互式、高效率的Web页和基于Web的功能强大的服务器应用程序。ASP可以在Microsoft的任何Web服务器上发布各种动态数据,而且ASP应用程序很容易开发和修改。     

基于Web服务的超图图像的动态生成及发布

在产品创新设计过程中,来自用户的评价可以帮助设计人员对产品进行创新和完善。本文给出一个利用ASP．NET技术开发的产品信息Web服务实例,可以动态生成并发布超图图像,使设计人员和用户能够获取产品模型信息,然后返回对产品的意见。该Web服务使用标准协议,能被跨平台的客户端应用访问,而且采用了动态生成图像的技术,可以有效地节省图像的存储空间。     

开发应用文摘

用ActiveX控件制作交互式多媒体演示的方法廉育功ActiveX是Mcrosoft提供的一项多媒体技术。它有很多功能强大的控件可供用户方便快速地设计Internet的Web页面或开发其他应用程序。在Office97／2000中,Microsoft已将ActiveX控件集成到World.EXcel.PowerPoint等软件中,使得这些著名的工具软件又上了一个新台阶。要全面了解和掌握ActiveX控件并非一日之功,本文仅从一个侧面用实例简要介绍怎样在PowerPolnt环境下电ActiveX控件开发交互式多媒体演示程序。4CtjV6I控件用于刚川开发王勃动态Web页面DHTM的开发方｝去很多如使用扩展标记…     

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。     

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.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

Enhancing a leaf radiative transfer model to estimate concentrations and in vivo specific absorption coefficients of total carotenoids and chlorophylls a and b from single-needle reflectance and transmittance

The relative concentrations of different pigments within a leaf have significant physiological and spectral consequences. Photosynthesis, light use efficiency, mass and energy exchange, and stress response are dependent on relationships among an ensemble of pigments. This ensemble also determines the visible characteristics of a leaf, which can be measured remotely and used to quantify leaf biochemistry and structure. But current remote sensing approaches are limited in their ability to resolve individual pigments. This paper focuses on the incorporation of three pigments—chlorophyll a, chlorophyll b, and total carotenoids—into the LIBERTY leaf radiative transfer model to better understand relationships between leaf biochemical, biophysical, and spectral properties.Pinus ponderosa and Pinus jeffreyi needles were collected from three sites in the California Sierra Nevada. Hemispheric single-leaf visible reflectance and transmittance and concentrations of chlorophylls a and b and total carotenoids of fresh needles were measured. These data were input to the enhanced LIBERTY model to estimate optical and biochemical properties of pine needles. The enhanced model successfully estimated reflectance (RMSE = 0.0255, BIAS = 0.00477, RMS%E = 16.7%), had variable success estimating transmittance (RMSE = 0.0442, BIAS = 0.0294, RMS%E = 181%), and generated very good estimates of carotenoid concentrations (RMSE = 2.48 µg/cm², BIAS = 0.143 µg/cm², RMS%E = 20.4%), good estimates of chlorophyll a concentrations (RMSE = 10.7 µg/cm², BIAS = − 0.992 µg/cm², RMS%E = 21.1%), and fair estimates of chlorophyll b concentrations (RMSE = 7.49 µg/cm², BIAS = − 2.12 µg/cm², RMS%E = 43.7%). Overall root mean squared errors of reflectance, transmittance, and pigment concentration estimates were lower for the three-pigment model than for the single-pigment model. The algorithm to estimate three in vivo specific absorption coefficients is robust, although estimated values are distorted by inconsistencies in model biophysics. The capacity to invert the model from single-leaf reflectance and transmittance was added to the model so it could be coupled with vegetation canopy models to estimate canopy biochemistry from remotely sensed data.     

Mr. Twinn’s bombes

This article discusses the history and design of the special versions of the bombe key-finding machines used by Britain’s Government Code & Cypher School (GC&CS) during World War II to attack the Enigma traffic of the Abwehr (the German military intelligence service). These special bombes were based on the design of their more numerous counterparts used against the traffic of the German armed services, but differed from them in important ways that highlight the adaptability of the British bombe design, and the power and flexibility of the diagonal board. Also discussed are the changes in the Abwehr indicating system that drove the development of these machines, the ingenious ways in which they were used, and some related developments involving the bombes used by the U.S. Navy’s cryptanalytic unit (OP-20-G).