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31.
《History & Technology》2012,28(3):281-309
Prior to the launch of Sputnik, knowledge about human space travel was widely circulated by spaceflight proponents, scientists and news producers in mainstream culture through print, film and broadcast media and displayed in public sites such as museums and public exhibition spaces. Focusing on the timeframe 1947–1953, this article examines how key members of the British Interplanetary Society used a combination of craft skills, graphical technologies, and communication media to create pictures and models to support rhetorical claims that spaceflight and astronautics are legitimate fields of scientific research and space travel could and should be achieved in the near future. Production and circulation of factual knowledge about space travel was not confined to material and discursive practices in established fields such as astronomy and aeronautical engineering. Actors from other professional, non-professional, and social groups contributed to the realization of future spaceflight as an heterogeneous cultural endeavor or astroculture encompassing an array of technical processes, artifacts, craft skills, and scientific knowledge.  相似文献   
32.
孙淼 《故宫博物院院刊》2012,(1):148-155,161
"明永乐宣德文物特展"是一个全面展现明早期艺术的综合性文物大展。展览的最终目的是要激发大众对传统艺术的兴趣,令其得到文化的熏陶与艺术的启迪,因此,展览陈列设计所要考虑的是一个多层次的体系。首先提炼装饰元素作为视觉主题,将艺术品的美感尽可能展现给观众,同时还要向观者传递时代背景、皇帝的思想境界等信息。此外,设计者还精心挑选不同的装饰材料以营造新颖的展示环境,达到衬托文物高超工艺水平的目的。  相似文献   
33.
Community‐based conservation is experiencing a crisis of identity and purpose as a result of a disappointing track record and unresolved deficiencies. The latter include over‐simplified assumptions and misconceptions of “community,” the imposition of externally designed and driven projects at the community level, a focus on conservation outcomes at the expense of community empowerment and social justice, and limited attention to participatory processes. New approaches are urgently needed to address these weaknesses and to counter a rising trend towards environmental protectionism and a preference for conservation approaches at an eco‐regional scale that threaten the interests of local and Indigenous communities. We propose that three core principles of community‐based participatory research (CBPR)—(1) community‐defined research agenda; (2) collaborative research process; and (3) meaningful research outcomes—hold much promise. Drawing on the experience of a research partnership involving the James Bay Cree community of Wemindji, northern Quebec, and academic researchers from four Canadian universities, we document the process of applying these principles to a community‐based conservation project that uses protected areas as a political strategy to redefine relations with governments in terms of a shared responsibility to care for land and sea. We suggest that basic assumptions of CBPR, including collaborative, equitable partnerships in all phases of the research, promotion of co‐learning and capacity building among all partners, emphasis on local relevance, and commitment to long‐term engagement, can provide the basis for a revamped phase of community‐based conservation that supports environmental protection while strengthening local institutions, building capacity, and contributing to cultural survival.  相似文献   
34.
对隋唐都城设计尺度的还原分析表明,两京的尺度设计分别以数字"九"与"七"为基数控制宫、宫城与皇城、郭城、市、苑囿的东西广度,并以9:10与1:1为基准比例,确定全城的尺度结构与规模。两京的设计与布局方法与萌生于北魏洛阳,并影响到了同时期东亚其他都城的布局设计,同时也对唐以后中国历代王朝都城设计产生重要影响。  相似文献   
35.
L’adaptation aux changements climatiques dans les réseaux d’aires protégées du Canada : état des lieux La Commission mondiale des aires protégées a récemment laissé entendre que les actions en faveur de la conservation sont vouées à l’échec, à moins que ces dernières tiennent compte des changements climatiques. Pour ce faire, les organismes chargés des aires protégées doivent dès maintenant s’assurer de l’intégration des changements climatiques dans les politiques, les cadres de planification et les modes de gestion. Le présent article rend compte des résultats d’une enquête réalisée conjointement par l’Université de Waterloo et le Conseil canadien des aires écologiques. Celle‐ci vise à dresser un état des lieux sur l’adaptation aux changements climatiques dans tout le réseau d’aires protégées du Canada qui relève du palier fédéral, provincial ou territorial. Il se dégage de l’analyse plusieurs constats importants. Tout d’abord, sur l’ensemble des organismes chargés des aires protégées que nous avons interrogés, les trois quarts ont déclaré que les changements climatiques ont déjà des effets visibles sur leur réseau d’aires protégées. Ensuite, 94 pour cent des participants à l’enquête estiment qu’au cours des vingt‐cinq prochaines années, l’enjeu des changements climatiques sera au c?ur de la politique et de la planification des aires protégées. Finalement, malgré la perception voulant que les changements climatiques exercent une pression croissante, la portée des mesures politiques, de planification, de gestion ou de recherche mises de l’avant par la plupart des organismes jusqu’à maintenant demeure limitée. Si 91 pour cent des organismes indiquent ne pas disposer des capacités nécessaires en ce moment pour réagir de façon optimale aux changements climatiques, l’enquête a permis de mettre en évidence un écart significatif entre la perception de la gravité des changements climatiques et la capacité des organismes chargés des aires protégées de s’adapter. La faiblesse du financement, une capacité d’action limitée, et un manque de compréhension des changements climatiques et de leurs répercussions réelles ou potentielles comptent parmi les difficultés auxquelles sont confrontés les organismes canadiens chargés des aires protégées. Il est impératif de les surmonter afin que ces organismes puissent exercer leurs mandats et être en mesure d’assumer leurs responsabilités concernant la protection et la biodiversité des aires, par exemple, la protection de l’intégrité du patrimoine naturel au Canada dans un contexte de changements climatiques accélérés.  相似文献   
36.
Damage phenomena observed in structures subject to intense seismic events are the result of stiffness and strength degradation. This paper studies the damage assessment of hysteretic degrading structures described by means of the Bouc-Wen model, modified to represent the mechanical degradation induced by severe earthquakes. In order to consider randomness of seismic action, the analysis is performed by adopting a stochastic approach and the Park and Ang damage functional is also evaluated in stochastic way. A parametric analysis is carried out with the aim to analyse the effect of mechanical characteristics and measure parameters of earthquake intensity on seismic response and damage level. Damage spectra are finally obtained and they are used to develop, on the basis of the Performance Based Seismic Design, ductility demand spectra.  相似文献   
37.
This article investigates a damage-based design approach for circular reinforced concrete (RC) columns under combined bending, shear, and torsion using decoupled damage index models. The combination of bending moment, shear, axial, and torsional loading affects the structural performance of bridge columns with respect to strength, deformation capacity and progression of damage. The damage index model proposed here permits decoupling these combined actions according to various damage limit states. This work evaluates the interaction between bending and torsional damage indices in terms of progression of damage. It also investigates the effects of the transverse reinforcement ratios and shear span. Based on experimental and analytical results increase of torsion amplified the progression of damage. The increase in transverse reinforcement ratio was found to have delayed the progression of damage and to have changed the torsional dominated behavior to flexural dominated behavior under combined bending and torsion.  相似文献   
38.
A procedure for deformation-controlled, or displacement-based, seismic design of multistorey RC buildings is proposed, implemented and applied for the full design of a four-storey RC structure. It is integrated into the overall structural design, along with the design for the non-seismic actions and consists of a ULS verification against the conventional strain limits for a frequent “serviceability” earthquake and of proportioning the compression reinforcement and the transverse reinforcement of critical regions of members to meet the member peak inelastic chord rotation demands under the “life-safety” seismic action. Quantitative rules and expressions are proposed for the estimation of (a) mean and upper-characteristic peak inelastic chord rotation demands, through appropriate linear-elastic analyses, and (b) mean and lower-characteristic values of member ultimate chord rotations, in terms of member geometric and material data.  相似文献   
39.
The following appraisal is by Eduard M. Murzayev, physical geographer and toponymist, with interests in Mongolia and Central Asia, who was a student of Berg at Leningrad University, and since this graduation in 1930 has been associated with the Institute of Geography of the Academy of Sciences USSR, first in Leningrad and after 1936 in Moscow. This article is based on a talk given by Murzayev in March 1976 at a memorial session of the Geographical Society USSR in Leningrad.  相似文献   
40.
巫濛  白藕 《东南文化》2022,(1):178-184+191-192
历史博物馆展览作为被观看的客体,以历史遗存为基础、以叙事为核心、以沉浸式体验为吸引观众达成展览目标的途径。历史博物馆展览中的景观意味着由文物展品与多种媒介物构成的具有一定叙事与意义表达的空间图示,并具有“器-象-道”三个层面。景观化可以广义地理解为将零散的元素组织成为具有意义指向的整体。“象”作为蕴含着“器”与“道”的感知整体,是营造体验、让观众形成第一印象的关键所在,因而景观化建构应以“象”为先,根据各自的基础条件运用不同的建构途径--利用天然的历史景观、重构历史场景、景观化的文物组合,从而有助于历史博物馆打造更具吸引力与更具传播效能的展览。  相似文献   
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