组态监控系统在人工模拟降雨试验中的设计与应用

介绍了一种应用于人工模拟降雨试验的监控系统,它基于力控组态软件,应用现有的人工模拟降雨试验装置,将试验过程的常用设备和工控软件结合在一起,解决了手工调节水压的不方便及原有的控制器不能同步控制多台人工模拟降雨装置的问题,实现了对不同雨强、不同分布、不同历时的人工模拟降雨过程集中控制。采用监控组态系统更好的满足了人工模拟降雨试验的需求。     

野外便携式人工模拟降雨系统的研制与应用

人工模拟降雨系统适用于需要人工模拟降雨并且控制降雨雨强和降雨时间等的各种试验场合。本课题研究了一种野外便携式人工模拟降雨系统,与国内外中小型野外人工降雨模拟装置相比,具有先进、稳定、降雨面积大、降雨雨强变化范围广、经济效果好等特点,是一种较理想的人工模拟降雨装置。     

基于粒子系统的大规模漫游环境实时降雨模拟

降雨是一种重要的自然现象,对降雨的模拟可以大大提高虚拟场景的真实感,粒子系统是模拟降雨的一种有效方法。针对已有降雨模拟方法的不足,提出一种应用于大规模漫游环境下实时降雨的新方法。首先通过分析雨的行为,建立恰当的雨滴粒子模型;其次通过在极坐标内生成雨滴粒子,提高粒子的利用率;最后就风对于雨滴的干扰作用进行计算,模拟出了逼真的雨滴运动过程。实验表明,该方法生成的大规模漫游环境下的雨景真实自然,实时性高,具有一定的实用价值。     

航海雷达测波系统中降雨观测资料的分析与处理

在利用航海雷达进行海浪观测时,降雨的出现会改变海面粗糙度,从而导致雷达所接收到的回波信号强度发生改变。通过对实际海浪观测资料的分析,提出一种对航海雷达测波系统中降雨观测资料的分析与处理方法,运用雷达回波影像的统计特性-均值和变异系数作为降雨与非降雨雷达影像的分类标准,然后利用中值滤波算法对降雨观测资料进行滤波处理,以降低降雨对回波影像的影响,同时探讨了中值滤波算法的适用性。实验结果表明本算法具有较强的鲁棒性和较高的通用性。     

基于SWMM的北京市河流降雨分析

提出了一种基于雨洪管理模型SWMM,并依据北京市河流雨季的径流曲线来分析北京市降雨径流特征,从而来探索北京市雨洪利用的方法.根据北京市河流、卫星资料、密云和北京雨量站的北京市降雨资料及气象资料等,建立了北京市河流降雨的SWMM仿真模型,对北京地区河流不同雨量观测站、同一条河流不同年分降雨及不同河流同一降雨下的降雨径流进行了模拟.从模拟结果可以看出,采用该方法能够模拟计算出北京市河流的降雨径流量,为北京市雨洪利用提供相应的支持.     

虹吸排水自补偿降雨量测量装置

针对传统虹吸式雨量计虹吸时产生计量误差,在野外环境难以实现自动化测量的问题,本文设计了一种基于称重传感器的虹吸排水自补偿降雨量测量装置。通过称重传感器将降雨重量转变为电信号输出,经数据采集处理系统完成电信号的差分放大、模数转换和数据处理,得到降雨量。为了提高降雨测量精度,通过对虹吸过程实验数据的分析,建立了一种高精度虹吸补偿数学模型,消除了降雨随虹吸排水造成的计量误差。该装置通过太阳能供电和完善的电源控制方案实现了能量自给,可以在野外环境长期稳定工作。实验结果表明：虹吸补偿算法提高了降雨测量精度,该装置的降雨测量误差范围在1%以内,并实现了在线实时监测,具有供电方便、通信稳定、测量精度高等优势。     

Ka频段卫星通信上行链路自适应功率控制

为提高Ka频段（30GHz／20GHz）卫星通信系统上行链路功率控制的可靠性,提出一种上行链路自适应功率控制算法。该方法基于自回归滑动平均模型,能由测量到的下行链路降雨衰减值预测出上行链路的降雨衰减值,从而提高功率控制精度。仿真结果表明,该方法对降雨衰减具有较好的补偿效果。     

分布式带电粒子催化人工降雨雪远程综合控制系统

为了解决传统人工降雨技术存在的限制和不足，各国都在积极开展新型人工降雨技术的研究，带电粒子催化人工降雨技术就是新型人工降雨技术的一种，该方法通过架设在野外的带电粒子发生器基站产出带电粒子催化降雨。进行带电粒子催化人工降雨雪实验需要远程控制基站中的各个实验设备，并对实验区域内的气象数据进行实时监测，因此需要实现一个综合控制系统。根据实验的具体需求实现了该系统，系统与不同类型设备连接的软件接口基于大型实验系统控制框架CFET开发，可以便捷地添加设备和管理设备。该系统被设计为通过网络连接的分布式系统，能满足多个实验点集中控制的需求。     

降雨环境下的多阶散射蜂窝系统信号特性分析

为精确研究信道模型的空间和时间特征,提出一种基于椭圆几何并考虑降雨衰减效应的郊区密集乔木林区多阶散射信道模型。推导一阶与二阶散射系统波达信号的到达时间(TOA)和到达角(AOA)的联合概率密度函数(PDF),对该模型进行仿真。仿真结果表明,随着降雨强度的增加,经历多阶散射的波达信号到达时间将产生显著延迟,概率密度更加接近均匀分布,且阶数越高,降雨作用的影响越明显。仿真结果有利于进一步研究蜂窝通信系统功率延迟分布,推导降雨环境下的循环前缀,分析OFDM系统的性能。     

基于图像挖掘技术的降雨预测系统的研究

目前,计算机图像识别技术已经被广泛地应用于天气和降雨预测等气象预报部门,但是对于短期和局部的降雨预测而言,其准确性和快速性都无法满足人们的需求;基于此,提出了一种基于卫星云图挖掘的降雨预测应用系统,通过提取雨量站的局部图像特征以及相关联的降雨量,获得其强关联规则以此作为降雨预测的先验知识库;最后通过对当前云图的特征提取,并依照先验知识库进行推理,最终给出预测结果;实验结果表明,该系统有比较好的实用效果。     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。