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排序方式: 共有112条查询结果,搜索用时 31 毫秒
41.
武汉城市圈节能建筑的处理方法及利用   总被引:1,自引:0,他引:1  
从武汉城市图建筑节能的重要性及武汉市建筑节能的现状入手,指出为达到建筑节能50%的标准,武汉节能建筑处理方法应从建筑设计、建筑施工、节能技术开发应用及建筑节能管理等多方面下功夫.图8,参7.  相似文献   
42.
An IT perspective on integrated environmental modelling: The SIAT case   总被引:1,自引:0,他引:1  
Policy makers have a growing interest in integrated assessments of policies. The Integrated Assessment Modelling (IAM) community is reacting to this interest by extending the application of model development from pure scientific analysis towards application in decision making or policy context by giving tools a higher capability for analysis targeted at non-experts, but intelligent users. Many parties are involved in the construction of such tools including modellers, domain experts and tool users, resulting in as many views on the proposed tool. During tool development research continues which leads to advanced understanding of the system and may alter early specifications. Accumulation of changes to the initial design obscures the design, usually vastly increasing the number of defects in the software. The software engineering community uses concepts, methods and practices to deal with ambiguous specifications, changing requirements and incompletely conceived visions, and to design and develop maintainable/extensible quality software. The aim of this paper is to introduce modellers to software engineering concepts and methods which have the potential to improve model and tool development using experiences from the development of the Sustainability Impact Assessment Tool. These range from choosing a software development methodology for planning activities and coordinating people, technical design principles impacting maintainability, quality and reusability of the software to prototyping and user involvement. It is argued that adaptive development methods seem to best fit research projects, that typically have unclear upfront and changing requirements. The break-down of a system into elements that overlap as little as possible in features and behaviour helps to divide the work across teams and to achieve a modular and flexible system. However, this must be accompanied by proper automated testing methods and automated continuous integration of the elements. Prototypes, screen sketches and mock-ups are useful to align the different views, build a shared vision of required functionality and to match expectations.  相似文献   
43.
本文简述了我校图书馆自动化建设的历史进程,分析了图书馆自动化建设的现状、达到的效果和尚存在的问题,并针对这些问题,提出了相应的改进措施。  相似文献   
44.
目的 针对实际装备中使用的串联锂离子电池组的不一致性问题,提出一种基于Buck-Boost电路和反激式变压器均衡电路的分层主动均衡构架.方法 以荷电状态(SOC)作为均衡标准,制定均衡策略,建立锂离子电池二阶等效电路模型以及开路电压(OCV)特性曲线来进行参数辨识与SOC估计.实现电池组内相邻电池单体间的能量转移以及电池组间任意模组到整体的能量双向传递.最后在Matlab/Simulink中搭建均衡模型进行仿真验证.结果 分层主动均衡构架相比传统单一相邻电池均衡构架具有更好的均衡结果,其均衡效果提升了43.04%,均衡时间缩短了24.4%,均衡效率提高了12.61%.结论 该分层主动均衡构架充分发挥了两种主动均衡的优点,改善了电池组的不一致性问题,并提高了整个电池组的充放电容量.  相似文献   
45.
复杂电磁环境数字仿真系统研究   总被引:2,自引:2,他引:0  
王东 《装备环境工程》2018,15(1):100-104
目的为夺取未来战场的制电磁权,缩小同国外先进水平的差距,需要构建一套标准化具可行性的复杂电磁环境数字仿真系统。方法从控制显示、武器模型、战场监测以及效能评估等角度出发,提出复杂电磁环境数字仿真系统的基本结构。论述控制系统、武器系统、监测系统、评估系统以及显示系统等各分系统的具体设计方法。结果综合考虑系统的重构性、扩展性、复用性以及操控性,搭建复杂电磁环境数字仿真系统的技术实现架构。结论为复杂电磁环境数字仿真系统的标准化与可行性的发展提供思路。  相似文献   
46.
Using Gall Wasps on Oaks to Test Broad Ecological Concepts   总被引:1,自引:0,他引:1  
Abstract:  Planning conservation of insect herbivores requires knowing what needs to be conserved and developing a set of predictor variables that aid management. We conducted a state-wide survey to examine the species richness of gall wasps (Hymenoptera: Cynipidae) on six oak species dominant in the threatened scrub-oak vegetation in peninsular Florida. Eighty-eight cynipid species were recorded; 23 were new species to Florida (a 35% increase), including 17 species new to science and 6 species newly recorded in the state. The cynipid species represented 68% of cynipids of Florida, on only 24% of oak species sampled. This fauna represents a hotspot of richness, justifying conservation initiatives in scrub-oak habitat and throughout the state. We derived predictor variables from general ecological concepts: (1) the theory of island biogeography that insect species richness increases as host plant geographic area increases and as local abundance increases, (2) the plant-architecture hypothesis that insect species richness increases with increased plant size, and (3) phytochemical patterns in leaves, including nutrients and digestibility reducers predicting suitability for insect herbivores. Concepts 1 and 2, developed for large scales and species numbers, were tested at smaller scales relevant to much conservation research and management. A stepwise multiple regression including all predictor variables accounted for 99% of the variance in cynipid species richness with three variables: foliar hemicellulose concentration (81%), host geographic area (16%), and tree height (2%). The trends were negative, however, and opposite to those predicted by concepts 1 and 2. Ecological theory was not applicable to discovery of predictors of cynipid species richness on six oak species. Thus, we promote caution in applying ecological theory to a narrow set of species without specific testing of how patterns conform to theoretical predictions.  相似文献   
47.
归纳了当前测试系统的主流总线架构形式,对当前各种总线架构的测试系统性能及应用进行了分析,同时对当前测试系统的主要软件设计技术现状进行研究。在此基础上,提出了未来复杂测试系统研制的主要方向,要满足未来复杂测试任务需求,应加大应用LXI总线构建大型高精度混合型分布式测试系统。硬件方面,将VXI/PXI/PXI-E/PCI-E/USB3.0总线进行组网集成,满足大型应用测试中低速、高速、高精度的数据采集与传输测试需求;软件方面,应按照行业标准需求,研制功能完备、满足特定行业应用的软件系统。  相似文献   
48.
Taiwan government specifies that the average roof thermal transmittance must be less than 0.8 (w/(m2·k)) for the design of all residential buildings in order to implement the policy of saving energy. However, self-disciplined architects practice the design of aesthetic roof to blend in with green landscape so that they urgently expect the academia to provide roof greening technical information to support their idea of designing green roofs for residential buildings. In this research, a single-family housing unit is used for investigating the possibility of applying extensive roof greening to achieve building sustainable development. The experiment tasks focused on the soil denudation caused by rainwater washing and replenishing the soil carbon by irrigating the soil with gray water. Using tap water to irrigate the green roof for 12, 16, and 14 weeks causes nitrogen, phosphate, and potassium, respectively, to be reduced to less than the original levels, respectively. Applying gray water to irrigate the green roof soil will raise the soil fertility by improving nitrogen and phosphate but not obvious for potassium.  相似文献   
49.
生态环境大数据建设是一项长期性、系统性的工作,需要科学、合理的顶层设计从全局的角度出发,对任务的各方面、各层次、各要素统筹规划,集中有效资源,高效、快捷地实现既定目标。本文总结了开展总体框架设计面临的主要问题;论述了顶层设计的基本概念和特征、原则和设计方法,阐述了大数据顶层设计与信息化顶层设计的关系,提出了生态环境大数据业务架构的设计方法、总体框架,并探讨了总体框架落地的主要思路。  相似文献   
50.
进入21世纪以来,保护生态环境和可持续发展已成为当下横置在世界各国面前的一道难题.论文根据"REVIT杯盘锦红海滩湿地公园候鸟之家设计大赛"所提供的条件和要求,秉着实现高速可持续发展的同时,最大限度地保留原有自然环境的原则,完成了盘锦红海滩湿地公园候鸟之家的筑内坏境、外环境、能源系统、水系统、材料选择等方面绿色策略的选择与应用.最终力求在人类活动需求与减少建筑对环境的影响之间寻找一个平衡点,从而实现可持续发展,永远保持绿色环境.  相似文献   
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