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31.
ABSTRACT

The interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes.  相似文献   
32.
敦煌文献中保存了许多唐五代时期地方各级水利官吏的设置运作状况记录。唐代前期设都水令,为当时敦煌“统以千渠”的最高级别水利官员。中唐吐蕃统治时期设“水官”“部落水官”以及“水监”“部落水监”“地方总水监”。晚唐五代归义军时期专设水司,长官为都渠泊使,下设多名水官。敦煌绿洲四界及寿昌灌区分别设置多名有特殊责任的水官“平水”,以“平治水利”,平水“相量”为务。此外,每条灌渠、每座斗门均设渠头或斗门长,属基层一级。这套水利官吏系统层层负责,相互配合,有效保证了农田灌溉顺利进行。同时敦煌民间还自发地组织起一批“渠人社”,这对地方政府水利管理体系是有益的补充。研究历史上水利官吏系统及其运作状况,对今天河湖运行和治理管护也具有借鉴作用。  相似文献   
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34.
The arrival of the term Geographical Information System (GIS) in the 1960s soon created a demand for training and education in the use of this specialist hardware and software. Initially the main focus was on training people to use GIS, formal named degree programmes leading to postgraduate and undergraduate qualifications arrived later. This paper explores the changing landscape of U.K. degree level GIS education drawing on contemporary information from Higher Education Institution websites and a case study of the first single honours degree in GIS in Europe. The paper identifies a rise and fall in the number of named undergraduate “GIS” degrees since the late 1980s sandwiched between the continuation and development of postgraduate qualifications. In parallel with this trend the teaching and learning of GIS skills has emerged as a core component of undergraduate degree programmes with “Geography” in their title and in national school and degree level benchmarking statements for the discipline.  相似文献   
35.
Debates on how to address societal challenges have moved to the forefront of academic and policy concerns. Of particular importance is the growing awareness that to deal with issues such as ageing, it will be necessary to implement concerted efforts on technological, social, institutional or political fronts. Drawing on a number of theoretical perspectives – including socio-technical transitions and embedded state theory – the aim of this paper is to identify and understand different approaches to the governance of such system innovations by comparing state responses to assisted living in two contrasting national systems of care, namely that of the UK and Norway. Its findings highlight that state-supported and funded experimentation projects have been instrumental in designing and implementing system innovation: through their emphasis on co-design and co-creation, these projects demonstrated the value of early implementation pilots to explore the ‘fit’ between novel technologies and prevailing practices and institutional structures in national systems of care. Still, competition, biases or conflicting interests should not be ignored between well-established agents and institutions and experimental solutions whose efficacy remains relatively untested and which involve a combination of new technical, social, organizational and institutional solutions.  相似文献   
36.
The entrepreneurial ecosystem (EE) literature has attracted much attention, especially in policy circles. However, the concept suffers from a number of shortcomings: (1) it lacks a clear analytical framework that makes explicit what is cause and what is effect in an EE; (2) while being a systemic concept, the EE has not yet fully exploited insights from network theory, and it is not always clear in what way the proposed elements are connected in an EE; (3) it remains a challenge what institutions (and at what spatial scale) impact on the structure and performance of EE; (4) studies have often focused on the EE in single regions or clusters, but lack a comparative and multi-scalar perspective and (5) the EE literature tends to provide a static framework taking a snapshot of EE without considering systematically their evolution over time. For each of these shortcomings, we make a number of suggestions to take up in future research on EE.  相似文献   
37.
古建筑木结构的残损点指标是对古建筑木结构进行结构安全评估和加固修缮设计的重要指标,目前主要依据1992年制定的《古建筑木结构维护与加固技术规范》(GB 50165—92)中的规定,为了对该规范中的构架整体性残损点指标进行验证和补充,本研究通过对南方地区传统的穿斗木构体系和抬梁木构体系的典型榫卯节点和构架的试验研究,得出两种木构体系结构的整体性关键残损点指标,并与GB 50165—92规范进行比较分析。结果表明:规范规定的抬梁式木构架和穿斗式木构架的局部倾斜残损点比试验结果小,规范值偏于安全。规范中规定的抬梁式木构架梁柱榫卯连接残损点略小于试验结果,规范值偏于安全;而规范中规定的穿斗式木构架梁柱榫卯连接残损点对于燕尾榫穿斗木构而言是安全的,但对于透榫穿斗木构而言,则是不安全的。  相似文献   
38.
This article explores the levels of fragmentation and fracture patterns in archaeofaunal assemblages from the lower basin of the Colorado River (Argentina) following Outram's methodology. Remains of ungulates (guanaco) have suffered, in these assemblages, a high degree of fragmentation probably caused during the processing of the carcasses. The presence of helical debris and shaft fragments indicates that fragmentation would respond to processing tasks for the consumption of marrow and possibly bone grease. The results of the application of this methodology that were obtained from the analysis of three late Holocene sites (La Primavera, Loma Ruiz 1 and El Tigre) are presented. These results provide new evidence not only for patterns of marrow and bone grease consumption but also for dealing with the subsistence model proposed for the study area. In this sense, the intensification processes already proposed during the final late Holocene (1000–250 bp ) are discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
39.
Dutch neuroscientist Cornelius Ubbo Ariëns Kappers is famous for pioneering neuroembryological work and for establishing the Amsterdam Central Institute for Brain Research. Less well known is his anthropological work, which ultimately played a role in saving Dutch Jews from deportation to their deaths during the Holocaust. Ariëns Kappers extensively campaigned against anti-Semitism and Nazi persecution during the 1930s. During World War II, he utilized his credentials to help create anthropological reports “proving” full-Jews were “actually” partial- or non-Jews to evade Nazi criteria, and at least 300 Jews were thus saved by Ariëns Kappers and colleagues. His earlier work demonstrating differences between Ashkenazic and Sephardic Jewish skull indices became the focus of an attempt to save hundreds of Dutch Portuguese Jews collectively from deportation. Ariëns Kappers and colleagues brilliantly understood how anthropology and neuroscience could be utilized to make a difference and to save lives during a tragic era.  相似文献   
40.
GIS技术在萨拉乌苏考古遗址公园规划设计中的应用   总被引:1,自引:0,他引:1  
传统规划设计工作的技术平台多以计算机辅助设计(CAD)为主,本工作以内蒙古自治区鄂尔多斯萨拉乌苏考古遗址公园规划为例,将Arc GIS Desktop作为技术平台应用到公园的规划设计工作中。首先,通过对规划区的实地踏勘,采集相关数据和资料,进行规划区数据库建设;其次,在数据库建设的基础上,通过GIS技术构建与现实环境对应的虚拟地理信息空间,实现规划区景观的三维可视化;最后,利用三维景观模型对现实地理环境进行模拟、分析及虚拟场景飞行。不同于传统CAD的二维工作平台,本工作借助GIS对空间数据和属性数据的强大处理功能及其三维景观可视化模块,为实现内蒙古鄂尔多斯萨拉乌苏考古遗址公园的科学规划提供辅助。  相似文献   
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