混合能源风机太阳能转化系统

混合能源风光互补转化发电系统,是一种风光互补发电装置,其主要包括太阳能光伏组件、风力发电机、逆变器、风光互补控制器、蓄电池等组件。该转化系统在一定程度上弥补了单一发电系统随环境制约的缺点,大大降低了风光单一发电的不稳定性。系统造价低,可靠性高、转化简单、继而实现能源利用最大化。     

开关磁阻风光互补发电系统最大功率输出研究

针对风能和太阳能等新能源的间歇性、可变等不稳定性特征,利用风能和太阳能的资源互补特性,将风能和太阳能通过转化、储存、控制等手段,形成稳定的电力输出。研究太阳能光伏发电系统和开关磁阻风力发电系统最大功率跟踪策略,提出一种适应天气变化较快的基于输出电压控制的最大功率点跟踪算法,结合蓄电池的智能控制策略,实现智能风光动态互补。MATLAB仿真实验验证了该控制方法的可行性和有效性。     

分布式发电微网控制系统的设计

为了节约能源和保护环境,人们已经努力发展和使用可持续能源。光伏发电、风力发电和燃料电池发电将成为今后主要的分布式发电方式。所设计的分布式发电微网控制系统,将分布式电源发出的最大功率通过微控制器、H桥电路、驱动电路、采样电路双闭环控制、储能装置,在负载或分布式电源输出功率变化时,利用双闭环系统以稳定直流母线电压,该系统使得最大功率跟踪模块能量可以向电网输送,实现能量的双向流动。经过测试,控制系统可以完成光伏电池的最大功率的输出控制,并使得在电压稳定度的范围内很小,且达到很高的稳压精准度。     

网络化数据采集系统在风光互补电厂中的应用

风能、太阳能属于可再生、无污染的清洁能源,风光互补发电系统是利用太阳能和风能的互补性,向负载提供稳定的输出;针对实际风光互补发电厂中各电站较为分散的特点,以及实现对风光互补发电厂的远程监控,运用CAN总线构建了包括各独立风光互补发电站的数据采集点在内的现场总线网络,并利用GPRS网络最终设计了一种新型的集数据采集、控制及远程通信于一体的风光互补发电厂远程监控系统;可对偏远地区无人值守的风光互补发电厂的运行及所获得的电能质量进行有效远程监控。     

基于滑模控制的独立光伏发电系统控制策略

针对独立运行的光伏发电系统,提出了基于滑模控制的最大功率跟踪(MPPT)策略;针对光伏微源输出功率随机性引起的逆变器输入侧直流母线电压波动,通过储能控制实现电压稳定;针对负载变化引起的系统输出电压波动,设计了系统输出电压电流双闭环控制器。通过MatLab/Simulink对提出控制策略进行了仿真验证。分析结果表明,所提出滑模控制策略可实现光伏电池的MPPT;储能控制策略可有效抑制光伏微源输出功率波动引起的直流母线电压波动;输出电压控制策略能稳定系统电压,确保安全可靠运行。     

基于multi-Agent和Petri网的分布式风光互补系统

近年来随着“大机组、高电压、大电网”发供电模式的弊端日益显露, 分散式供电系统成为21世纪电力工业的发展方向.此外, 随着风力、太阳能等可再生能源的飞速发展及其发电效率的不断提高, 使研究风光互补系统的分布式供电有着重要意义. 文中提出一种基于multi-Agent的分布式风光互补混合供电系统, 将分散的风力、太阳能光伏发电装置组成分布式系统, 并采用有色Petri网建立了multi-Agent的协作模型. 通过模拟风力–太阳能的运行情况, 证明了分散控制策略的有效性.     

风光互补发电在河套地区的应用分析

风能和太阳能是绿色、环保的可再生能源,取之不尽,用之不竭。通过对河套地区地形特点的分析,提出风光互补发电已成为新能源发展的趋势。风光互补发电系统就是将发电机组和光伏发电组合起来构成的发电系统,主要由发电系统、蓄电池控制器、逆变器等部分组成。阐述了风光互补发电系统的构成及其各部分特点,提出了河套地区风光互补发电系统的发展方向。     

基于RBF神经网络的风光互补路灯系统MPPT研究

为了提高风光互补路灯的稳定性和使用寿命,根据风光互补路灯系统非线性、多物理量等特性,分别对风力发电和光伏发电采取最大功率点跟踪(MPPT)控制。该方法基于径向基函数(RBF)神经网络,分别以风力发电整流器输出的电压、电流和太阳能电池板输出的电压、电流作为RBF神经网络的输入,通过RBF神经网络直接改变Boost电路的占空比,使风光互补系统工作在最大功率点。仿真和试验结果表明,所提出的MPPT算法与扰动观察法算法相比,有更好的快速性和能量利用效率。     

基于NSGA-II的并网型风光互补发电系统协调控制

针对并网型风光互补发电系统中,系统最大输出功率大于给定功率时,风力发电子系统和光伏发电子系统功率如何协调的问题,提出了一种功率协调控制方法.在该方法中,根据系统并网收益最大和输出电流谐波最小构建目标函数,采用带精英策略的快速非支配排序遗传算法对风力发电子系统和光伏发电子系统的输出功率进行多目标优化,协调控制子系统的发电功率;并以甘肃华电阿克赛风光互补发电项目为例进行了仿真验证.仿真结果表明,与传统的光伏优先接入方式相比,基于NSGA-Ⅱ的并网型风光互补发电系统协调控制方法可以更加合理地利用风能和太阳能,提高新能源电能的电网友好性.     

甘肃地区风能光伏互补发电研究

太阳能光伏发电与风力发电有机地结合在一起,既高效利用土地,又实现了太阳能与风能发电的优势互补,同时利用风电场已建成的送出系统,减少了投资,效益更加显著。风光互补发电系统推动了我国节能环保事业的发展,同时有助于资源节约型和环境友好型社会的建设。甘肃省风能、太阳能资源储量丰富,且分布集中,适宜进行大规模集中开发。本文对甘肃地区风能光伏互补发电进行了探讨。     

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.