电网电力系统稳定器的交互影响分析

随着我国大区域电网互联的发展,低频振荡已是影响电力系统稳定的重要因素之一.目前,在发电机励磁系统上安装电力系统稳定器(PSS)仍是抑制低频振荡的一种较为经济和有效的方法.在分析了多机系统中PSS的交互影响并考虑多机系统PSS的相关性的基础上,采用特征值灵敏度分析法确定机电振荡模式,建立了优化模型.由特征值对PSS增益的灵敏度构成目标函数,实现了发电机对各机电模式的有效参与,从而求得系统中各机电模式与主参与机组PSS的对应关系.某省级电网系统的计算和分析,验证了所述方法的可行性.     

新环境保护法对强化水资源管理的作用与启示

全国人大常委会审议通过的新环境保护法在很多方面有重大创新和突破,建立了对经济技术政策的环境影响评价制度,强化了有关部门监测信息公开义务,建立了环境资源承载能力监测预警机制;赋予了有关部门查封、扣押的权力,建立了跨区域联合防治机制、"黑名单"制度等,完善了公益诉讼制度;设置了更加严厉的法律责任,创设了按日连续处罚和连带责任,增加规定地方政府及有关部门主要负责人"引咎辞职"的政治责任。这些规定对于水资源管理具有重要作用和启示,在水资源管理工作中应当积极运用该法有关规定,借鉴相关制度,完善相应的法规和政策措施,推进最严格水资源管理制度的有效实施。     

城镇化进程中水土保持技术防治措施体系及其作用

近年,随着城镇化建设的快速发展,城市水土保持工作相应也提出了更高要求。在分析城市水土流失的成因、特点、危害的基础上,总结北京市经济技术开发区城市水土保持工作和归纳植物、工程、临时三大措施防治体系及其效益,提出编制专项规划,编写实施方案和设计,完善当地防治措施体系,推广生态措施,重视临时措施等新型城镇化建设中水土流失治理的方法。     

基于数字逻辑的PLC编程新方法

PLC技术的难点是根据工艺流程和控制要求编写控制程序.介绍了PLC技术编程的新方法—运用数字电路的逻辑分析方法进行程序设计.采用数字逻辑法编程的特点是逻辑关系非常简单、程序结构非常简洁,编程费时很短,无需绞尽脑汁,还能节省PLC的输入点,优点显著.     

An integrated new product development framework – an application on green and low-carbon products

Companies need to be innovative to survive in today's competitive market; thus, new product development (NPD) has become very important. This research constructs an integrated NPD framework for developing new products. In stage one, customer attributes (CAs) and engineering characteristics (ECs) for developing products are collected, and fuzzy interpretive structural modelling (FISM) is applied to understand the relationships among these critical factors. Based on quality function deployment (QFD), a house of quality is then built, and fuzzy analytic network process (FANP) is adopted to calculate the relative importance of ECs. In stage two, fuzzy failure mode and effects analysis (FFMEA) is applied to understand the potential failures of the ECs and to determine the importance of ECs with respect to risk control. In stage three, a goal programming (GP) model is constructed to consider the outcome from the FANP-QFD, FFMEA and other objectives, in order to select the most important ECs. Due to pollution and global warming, environmental protection has become an important topic. With both governments and consumers developing environmental consciousness, successful green and low-carbon NPD provides an important competitive advantage, enabling the survival or renewal of firms. The proposed framework is implemented in a panel manufacturing firm for designing a green and low-carbon product.     

试谈化工在中国新能源发展中的作用

阐述了在全球环境日益恶化、中国缺油少气,发展新能源和清洁能源已刻不容缓的形势下,化工行业所面临的挑战与机遇,提出开发研制新能源的新工艺和技术;提供高性能低成本的材料满足技术上的需求;借助化工工艺和设备,在新能源和清洁能源的辅助工序上提供解决方法等助推中国新能源发展的措施。     

关于新型多媒体教室环境合理构建的探讨

随着信息技术在高校教学的广泛应用,新型多媒体教室已经成为运用信息技术手段进行现代化教学的主要场所.从新型多媒体教室的现代化设计、人性化环境建设、基础设施的配置三方面进行了阐述,并探讨了构建合理的、人性化的多媒体教学环境的方法.     

对垃圾邮件过滤技术的问题研究

近年来,电子邮件方便人们的生活,同时,也有大量的垃圾邮件不断涌现,随之也出现了各种垃圾邮件过滤技术。文中主要介绍基于信件源垃圾邮件过滤技术和基于内容的垃圾邮件过滤技术,通过对这两种技术的介绍,分析了垃圾邮件过滤技术的优缺点,并对垃圾邮件过滤技术中存在的问题进行了讨论。垃圾邮件发送者不断改变发送策略以逃避过滤技术的过滤,垃圾邮件发送策略也不断的更新。文中对近年来垃圾邮件发送的新策略进行了详细的阐述,讨论目前垃圾邮件过滤技术研究中遇到的问题和挑战。     

Organometallic Pt(II) containing polymer as silver protection against sulfide tarnishing

In this work, the use of a film of an organometallic polymer, namely Pt‐DEBP, has been tested for the selective capture of sulfides with the aim of protecting silver object. Ag foils were exposed to different environmental conditions in the presence of Pt‐DEBP films. Scanning electron microscopy, energy dispersive spectrometry, and colorimetric studies allowed to assess that the polymeric layer selectively captures H₂S, preventing the tarnishing of the silver substrate over a period at least of 2 months, without any manipulation of the sample. This approach open new perspectives for the prevention of aging effects on silver objects of artistic interest, for which cleaning or coating procedures should be avoid. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

合理选择中密度纤维板生产工艺的思考与探讨

根据我国中密度纤维板生产线建设实践,就剥皮与水洗、干燥与施胶、铺装与预压、热压与砂光等工序生产工艺的合理选择提出了看法与建议。