空调系统多工况智能控制

本文分析了空调系统的组成与控制环节，针对空调系统全年节能运行工况分区，提出了基于自动化和产生式规则的多工况控制型和系统控制结构。     

串级控制在空调水系统控制中的应用研究及仿真

在对空调水系统中现有的两种控制策略进行分析后，出于提高系统节能效果的目的，提出了将串级控制方法引入到空调水系统控制中的思想，以西安建筑科技大学变风量空调实验室内的冷水系统为对象，通过最小二乘法辨识出其主、副环的传递函数，最后基于LabVIEW软件进行仿真分析，证明了串级控制策略在空调水系统控制中的研究价值。     

基于LabVIEW的空调水系统优化控制策略研究

在对空调水系统中的压差控制与温差控制两种控制策略进行分析后,为提高系统节能效果,将串级控制方法引入到空调水系统控制中;以西安建筑科技大学变风量空调实验室内的冷冻水系统为对象,提出用最小二乘法辨识串级回路主、副环的传递函数模型,并在此基础上,基于LabVIEW软件对控制系统进行仿真分析和实验研究;仿真和实验结果证明了串级控制策略在空调水系统控制中的有效性和良好的应用价值。     

地铁空调水系统节能控制研究

针对地铁水泵定频运行方式造成的能量浪费问题,对地铁车站冷冻水系统采取一次泵变频方式运行进行研究。根据地铁车站空调负荷规律性变化的特点,结合温差控制显著的节能效果,提出基于前馈-反馈的变温差控制策略,并在瞬时系统模拟仿真平台(TRNSYS)上对节能控制策略进行了仿真验证。实验结果验证了变温差控制策略应用于地铁空调水系统的可行性和正确性,节能效果显著,表明变温差控制策略可作为地铁空调节能控制的研究发展方向。     

智能控制在地铁通风空调系统中的应用

通风空调系统作为地铁中的重要设备系统之一,担负着对地下空间的空气温度、湿度、空气流速和空气品质进行控制的任务,而其能耗约为地下线能耗的30%以上,仅次于车辆牵引用电能耗,节能潜力相对较大。介绍了通风空调系统的运行模式和能耗测量方法,在分析能耗数据及能耗的基础上,提出了空调系统智能控制模块在环境综合监控系统(BAS)中的实现方案。     

中央空调系统的节能改造

中央空调系统的节能改造有很大的降耗空间,本文论述利用变频器和PLC的逻辑控制功能及数据通讯功能对原有空调系统实施改造的技术方案。对原空调的各个重要系统进行分析后,提出了控制系统方案及实现方法,完成了整套节能系统的改造。运行实践表明,该方案对中央空调系统降低能耗和提高效率具有重要意义。     

建筑空调节能控制探析

目的：研究实现智能建筑暖通空调系统节能的有效途径和优化方法。方法：分析比较建筑物内部主要耗能单元的节能措施。结果实现了对BA控制系统（主要是暖通空调系统）的传感器、执行器、控制器、网络等若干环节分级优化,从系统的各种可能结构和参数中找到最佳匹配,使整体效能最佳,从而提高系统的效率。结论：确立智能建筑暖通空调系统能量管理与控制系统优化的基本出发点、优化原则及技术措施对于智能建筑节能实现具有重要的现实意义,BAS系统是实现智能建筑节能的有效途径之一。     

变风量空调的自适应模糊PID复合控制

研究空调系统控制的优化问题,针对变风量空调系统是一个时变、非线性、纯滞后的复杂系统,要求达到舒适节能的环境.传统模糊控制和PID控制方法难以获得较好的控制性能.为解决控制系统中超调量大、振荡和控制精度不高等问题,提出了史密斯预估的自适应模糊- PID复合控制策略.在传统的模糊控制中加入自适应环节,通过模糊自适应校正解决了因模糊规则粗糙而造成控制精度不高,适应能力弱的问题.针对大滞后系统,采用史密斯预估补偿,减小了控制系统的超调和振荡.同时,用模糊与PID相并联的复合控制方式,提高了系统的动态性能指标和稳态精度.仿真结果证明,改进的控制策略响应快、控制精度高、鲁棒性强,为变风量空调系统的智能控制设计提供了参考依据.     

基于动态负荷需求分析的冷冻站测控系统设计

依据某病房办公楼空调系统的历史运行数据,进行了动态负荷需求分析,研究了空调运行冷负荷次数、时间频数和空调系统循环水温差随空调负荷变化趋势,提出了将模块化冷水机组4∶2∶4分组控制和空调水系统恒温差变频控制相结合的按需供冷方案。搭建了以PLC为核心的节能控制系统,经过运行实验,节能率26.1%,达到了很好的节能效果和经济性。     

变风量空调系统动态仿真研究

变风量(VAV)空调系统具有节能、空气品质高的特点,应用前景广阔.建立VAV空凋系统动态模型并进行仿真,对研究VAV空调系统的动态特性具有重要意义.引入容性环节与阻性环节相结合的方法,对VAV空调系统的关键部件进行更为合理的划分,解决了各部件模块间的可连接性问题;从对象工作机理出发,将各风道连接处的部件抽象为节点容积模型,从而简化了建模仿真的复杂度,提高模块的可重用性.利用所建模型对VAV空调系统的动态特性进行了仿真研究,计算结果证实了模型的有效性,并且可以满足实时动态仿真的要求,可以作为各类空调风系统仿真的参考模型.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate