基于GIS可视化的游乐设施在线监测与评估系统

根据目前国内游乐设施安全的实际情况,充分研究了现阶段的游乐设施的检测方法,结合VB、MAPX,F-AHP(模糊层次分析法)和BP神经网络等技术,开发了一套基于GIS可视化的游乐设施在线监测与评估系统.系统具有良好的人机操作界面,可以在线采集游乐设施的动态数据和分析游乐设施的安全裕度.在某游乐场进行试验后,系统运行效果良好.     

浅谈特种设备检验检测的安全管理

特种设备与我们生活是密不可分的。例如电梯、锅炉、气瓶、起重机械、客运索道、大型游乐设施等等都属于特种设备,与人民的生命财产安全息息相关。特种设备数量多,分布广,涉及生产、生活诸多方面,是人们日常工作、生活中广泛接触且不可缺少的设备设施。有效减少特种设备发生故障的概率,减少事故的发生,增强设备安全运行效率,是特种设备检验检测人员的必备职业素质。特种设备检验检测应该不断学习现代化先进技术,逐步强化工作技能。本文将对特种设备检验检测的安全管理作出讨论,首先分析了特种设备安全管理的可能问题,并提出改进意见。     

游乐设施座椅乘客束缚装置约束有效性研究

游乐设施乘客束缚装置约束是否合理有效,直接关系设备运行及乘客的人身安全.为确保乘载安全,正确选择乘客安全束缚装置至关重要.基于安全带、安全压杠和安全带安全压杠配合3种约束方案,分别建立了游乐设施乘客束缚装置的三维数字模型,并在Hypemesh、LS-PrePost中对模型添加约束,施加载荷,将模型导入LS-DYNA中实...     

基于模糊层次法的配电网停电风险预警系统

为准确及时地对配电网停电风险做出预警，降低电网事故发生概率，设计一种基于模糊层次法的配电网停电风险预警系统。根据设施设备、运行维护与网络架构水平，建立预警指标体系；利用模糊层次法构建指标模糊判断矩阵，获取指标的模糊综合度，经过归一化处理后得到权重集合；确定系统整体架构与工作流程，使系统具备实时监测、辅助决策、安全校验、动态预警与结果可视化等功能，在通信服务中实现数据传输、时序控制等软件性能。仿真实验表明系统能够为配电网安全运行提供技术保障。     

一种基于Multi-Agent的实时监控系统的设计和实现

基于Multi-Agent技术提出了一种多Agent实时安全支持系统结构模型，包括：故障感知Agent、故障诊断Agent和咨询解释Agent。它们的协同工作用于某超高压变电站安全监控环境、为大型实时监控系统的开发提供了一个成功的实例。     

移动Agent系统Mogent的安全设施分析

安全问题是移动Agent技术应用发展中的一个重要主题。本文详细分析了南京大学计算机软件新技术国家重点实验室研制的基于Java的移动Agent系统Mogent(Mobile Agent)的安全设施，主要包括密写操作与密钥管理、安全传输通道、访问控制、授权和电子货币。     

化工企业安全生产故障预警仿真系统

介绍了化工企业生产的特点和事故的特征,阐述了预防化工企业生产事故的技术手段,化工企业安全生产故障预警仿真系统是解决化工企业安全生产的一种有效手段。     

基于云平台的台区故障监测系统设计

传统监测系统在台区故障监测应用中常出现误测现象,且误测率较高,为此提出基于云平台的台区故障监测系统设计。系统硬件部分包括故障信号采集卡、微处理器以及预警器设备,利用故障信号采集卡采集台区故障信号,通过微处理器对故障信号进行处理并且对系统监测命令进行响应,通过预警器对台区故障进行及时预警;系统软件部分设计故障信号编码协议对台区故障信号进行分类,同时对台区故障进行编码,利用云平台分析台区故障信号,计算出台区故障概率,将其分析结果作为系统输出,以此实现基于云平台的台区故障监测系统设计。经实验证明,设计系统对于台区故障的误测率小于当前系统,具有较好的可行性和可靠性。     

基于局部离群因子的城市轨道交通行车安全防护设备状态监控系统

为了实现对城市轨道交通行车安全防护设备的智能化监控,提出基于局部离群因子的城市轨道交通行车安全防护设备状态监控系统设计方法。将安全设备的状态监控系统分为火灾自动报警系统、屏蔽门/安全门、广播系统、乘客信息系统等,结合对城市轨道交通行车安全防护设备安全影响因素,进行车辆段及设备应用配置分析,通过设施配备标准体系优化设计,实现对消防设施和综合监控设施配置,采用软件系统和预警接收单元联合控制的方法,采用局部离群因子检测,实现对城市轨道交通行车安全的烈度速报及视觉控制,实现城市轨道交通行车安全防护设备状态特征分析,提高状态监测的可靠性。测试结果表明,采用该方法进行城市轨道交通行车安全防护设备状态监控的可靠性较高,提高城市轨道交通的安全保障度。     

基于局部离群因子的城市轨道交通行车安全防护设备状态监控系统

为了实现对城市轨道交通行车安全防护设备的智能化监控,提出基于局部离群因子的城市轨道交通行车安全防护设备状态监控系统设计方法。将安全设备的状态监控系统分为火灾自动报警系统、屏蔽门/安全门、广播系统、乘客信息系统等,结合对城市轨道交通行车安全防护设备安全影响因素,进行车辆段及设备应用配置分析,通过设施配备标准体系优化设计,实现对消防设施和综合监控设施配置,采用软件系统和预警接收单元联合控制的方法,采用局部离群因子检测,实现对城市轨道交通行车安全的烈度速报及视觉控制,实现城市轨道交通行车安全防护设备状态特征分析,提高状态监测的可靠性。测试结果表明,采用该方法进行城市轨道交通行车安全防护设备状态监控的可靠性较高,提高城市轨道交通的安全保障度。     

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).