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971.
随着建筑结构的大型化、复杂化,利用结构健康监测(Structural health monitoring)技术评判结构的安全状态是非常重要的。本文基于BIM技术,结合数据库管理和传感通信技术构建了SHM系统框架,利用参数化设计工具Dynamo,由BIM模型自动访问SHM数据库,通过阈值设定,将损伤构件映射到BIM模型上,实现基于SHM数据进行结构状态评估的可视化预警能力。  相似文献   
972.
Establishing nutrient reference condition (baseline environmental condition) of lakes in ecoregion is a critical consideration in the development of scientifically defensible aquatic nutrient criteria. Three methods were applied to determine reference conditions in Yungui Plateau ecoregion lakes with respect to total phosphorus, total nitrogen, planktonic chlorophyll a (chl a) and Secchi depth. First, minimally developed lake/catchment units were identified based on existing geographical database and visual basin survey. Lakes in these catchments were considered minimally disturbed ‘reference lakes’. Second, the frequency distribution of all of the lake data presently available by each variable was plotted, and the lower 25th percentile was selected as the reference condition for each value. Third, median nutrient, chl a and Secchi depth values were determined for the best one‐third of lakes and applied as indicators of reference condition. The result of model prediction and data from historical record were used to test three techniques for determining reference condition. Reference conditions, as determined by these three methods, broadly agreed for all parameters. Overall, the data suggest that multiple methods can be used to determine reference condition, and that in Yungui lakes, reference condition corresponds to oligotrophic–mesotrophic status.  相似文献   
973.
Stockaded villages of the Qiang nationality that are made up of watchtowers and watch-houses are an important part of its cultural heritage. The earliest documentary records of its blockhouse-styled construction can be found in Biography of the Ethnic Minority Groups in Southwest China of History of Eastern Han. In 2006, watchtowers and stockaded villages of the Qiang nationality was placed in the preparatory declaration list of world cultural heritage in China and became a minority architectural heritage that is of potential value for world cultural heritage. The Wenchuan earthquake, which happened on May 12th, 2008, caused severe damage to settlements of the Qiangs in the upper reaches of Min River, including the “Tangping Qiang village,” which plays a prominent role in Qiang stockaded villages. In conserving this important architectural heritage, we observe the idea “everything for heritage value”. We discuss and draw up a series of salvage conservation countermeasures and research for antiseimatic key technology during post-earthquake reconstruction period of Tibetan and Qiang settlement engineering projects, including six engineering principles on priority of structure rescue, heritage value, former address maintenance, traditional way of use, protection against and mitigation of earthquake disasters, and spot cleaning and separating. We draw up three rules in engineering strategy, namely: (1) we should follow ultimate orientation of heritage value protection in rescue, maintenance, and protection engineering; (2) degrees of priority of engineering measures should be differentiated according to the situation of the disaster and residential situations of stockaded villages and; (3) we should keep local smiths and conventional art as the base, and modern technology as a supplement in rescue, maintenance, and protection engineering.  相似文献   
974.
幕墙作为建筑中的特殊领域,BIM全生命周期应用将是建筑幕墙创新发展的一个里程碑,特别是在复杂幕墙建造中至关重要。本文通过对众多幕墙项目的研究,分析当前环境下实现BIM正向设计存在的难点问题,研究BIM正向设计实现的思路,最后以实际案例分享幕墙BIM正向设计的实践过程。  相似文献   
975.
Introducing the case of the Kids’ Gardens in Yucai No. 3 Primary School in Changsha City, Hunan Province, this study established sociograms upon the contact-frequency-based network with UCINET to systematically analyze the characteristics of different participants in the process of the childfriendly community building and the varying pattern of all social relations, aiming at addressing problems emerging in public participation and multi-stakeholder collaboration in Chinese mainland. It was found that by bonding stakeholders including citizens, the government and party organizations, universities, and public institutions and enterprises, this practice encouraged the school — as a community — to leverage its internal resources. The school finally overcame the organizational inertia and achieved independent operation and growth during the process of community building. The study also demonstrated that the social network of participants was developed and defined with both independent and dependent modes from an overall perspective, of which the former characterized for its dominant internal ties and a dense tree-like hierarchical management structure might be more efficient. From a participant perspective, the brokerage roles in key nodes were critical to the community building. Finally, spatial design strategies, including enhancing the spatial affordance to serve diverse activities, space zoning and allocation, offering “half-done” spaces, and phased development, were provided for similar community building practice.  相似文献   
976.
为研究铁路隧道救援站火灾烟气蔓延的规律并为火灾情况下铁路隧道救援站内控烟方案设计提供技术依据,笔者建立了几何比尺为1∶50的铁路隧道列车行驶模型试验平台。通过室内模型试验,对自然通风以及3种轴流风机风速影响下铁路隧道救援站火灾烟气蔓延规律展开研究。同时,用Flunet数值模拟软件建立了动网格模型,计算了2种火灾工况结果并与模型试验进行对比分析。试验结果表明:隧道内活塞风大小受列车车速的影响,两者成正相关。未开启风机时,离火源较近的前后横通道均会被烟气侵入;开启右线主隧道两端风机进行2 m/s送风后,仅有7号横通道有烟气侵入。  相似文献   
977.
伦敦印象     
陈琦 《城市建筑》2007,(4):94-98
来伦敦前,我对伦敦的印象是一个个零散的片断——古老的城市、世界三大金融中心之一、雾都、著名的塔桥(图1)、泰特美术馆、伦敦古堡(图2)、千年穹顶(图3),当然还有诺曼·福斯特和里查德·罗杰斯。  相似文献   
978.
地表水在供冷供热中应用的现状及分析   总被引:4,自引:0,他引:4  
本文分析了国内外地表水供冷供热技术的应用现状,介绍了一些典型的工程实例。同时分析了我国地表水源热泵的应用前景,并重点介绍了位于湖南省湘潭市城市中心区的开式地表水源热泵区域供冷供热系统。  相似文献   
979.
本文认为方案设计是暖通空调系统设计中最复杂、难度最大的阶段,也是冷热源系统生命周期中最基础而又最重要的环节,是关系到暖通空调系统能否健康、有效运行的关键。系统方案的选择有很多方法。通过综合考虑技术,经济,环境和人文等因素,提出采用价值工程的评价方法在当前仍然是一个比较好的选择。此评价方法中功能重要程度对最终结果影响很大,不同得功能重要程度评判原则不同所得结果不同。  相似文献   
980.
香港的建筑工业化经过短短的十多年就获得了很大的成功.由开始预制部件仅用于政府兴建的公屋,逐渐为私人发展商和建筑公司接受,现已全面推广。在此进程中,香港政府出台的相关政策以及相关部门的引导、监管起到了重要作用。本文的三位作者都曾在香港建筑建材界就过职,亲历香港建筑工业化的过程,希望他们的此篇文章对我们的墙材革新及墙材产品的生产开发有所启示。[编者按]  相似文献   
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