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1.
本文总结多年来实践经验 ,分析研究避暑山庄皇家园林建设和管理中存在的问题 ,多方探索解决途径 ,进行有益尝试 ,提出了因地制宜的改进意见和建议。  相似文献   
2.
举办大型运动会与城市生态环境保护的探讨   总被引:5,自引:0,他引:5  
研究采用实地考察、文献分析以及生态学、城市规划、环境保护基本原理等。通过研究大型运动会城市生态环境问题的产生、特点和表现,提出举办大型运动会与城市生态环境保护协调措施。认为,大型运动会引起城市生态环境的问题主要表现在:(1)体育场馆设施建设;(2)建材的使用与废弃;(3)城市环境污染;(4)场馆设施与交通能源利用;(5)体育场馆设施赛后利用等。在举办大型运动会中,要确保城市生态环境的可持续发展,一是制定大型运动会城市生态环境保护具体规划,二是促进公众参与,加强城市环境治理。  相似文献   
3.
通过录像研究、资料查阅、数理分析等方法,依据能量转化与守恒定律,分析了撑竿跳高过程中的能量来源与转化, 总结出助跑、起跳、团身展体、引体推竿这四个过程是动能获得的根源;在整个跳跃过程中,一部分能量被损耗,另一部分转化为身体重心腾至最高点时的势能和过竿时的水平动能, 并提出:加强能量来源与减少能量损失是获得较高腾高的根本方法.  相似文献   
4.
可持续发展之路——论发展生态经济   总被引:2,自引:0,他引:2  
生态经济是生态与经济协调发展的一种经济形态。为了实现经济社会的可持续发展,必须加快实现生产方式的根本转变,大力发展生态经济。  相似文献   
5.
随着旅游的发展,旅游环境容量问题日益凸现,以普陀山为研究区域,从旅游环境容量的三个分量入手,对其进行阐述,并提出一些参考性的方法。目的是引起人们对此问题的重视,并在实践中不断地探索和完善。  相似文献   
6.
本文研究了矩阵光学中 ,矩阵逆变换和物理逆光路的逻辑自洽问题 ,揭示了抽象的矩阵操作和实际的物理过程的一致性 ,最后指出 ,它们的统一性 ,本质上在于宏观物理现象的宇称守恒性。  相似文献   
7.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   
8.
介绍了广西历代地方志的轸纂概况。分析了广西历代方志的价值,并讨论了广西历代方志的整理与保护问题。  相似文献   
9.
ABSTRACT

Control of relative humidity (RH) for collections care is challenging in U.K. historic houses because they are often highly ventilated with poor heat retention, a porous building fabric and naturally tend to high (60–80%) RH if unheated. The significance of the building means that large-scale modifications and installation of air handling systems may be unfeasible and undesirable for the conservation of the building. In the late 1980s the National Trust, for English, Wales and Northern Ireland, investigated conservation heating as an RH control method that works with the natural environment of historic buildings, mimicking historic heating and requiring only modification of existing heating services or a light touch installation of new heating systems. The National Trust adopted conservation heating as its preferred method for environmental control in historic buildings from the 1990s. This method was presented at the IIC 1994 Ottawa congress on preventive conservation. Conservation heating has since been adopted by many historic house management organisations, particularly across north-west Europe, where it is well suited to the climate. This paper reviews conservation heating developments implemented by the National Trust since 1994, in response to a changing external context, new knowledge and developments in operational practice.  相似文献   
10.
This paper examines how research impact is defined, measured, and generated – with a view to understanding how it can be enhanced within heritage conservation. It examines what is meant by ‘impact’ and how it can be promoted within heritage science through effective inter-disciplinary collaboration. Following a general examination of the current discourse concerning research impact, the study examined: (i) active research networks within heritage science; (ii) research planning and evaluation practices within heritage science; and (iii) the experiences of users (i.e. conservators and other heritage professionals) within research collaborations. Terminologies surrounding the notion of impact and the various phases of the research process were reviewed – from the initial identification of a knowledge gap to the eventual application of new findings in practice. Next, the reach and diversity of research collaborations (as identified through publication co-authorship) were studied to characterise the inter-disciplinary nature of heritage science and its connectedness to users. Findings showed substantial growth in international research collaborations over recent years, predominantly involving academic- and research-oriented institutions – although the engagement of heritage institutions has proportionally decreased. In addition, a worldwide survey of institutional planning and evaluation practices revealed a general reliance on processes driven by the interests of researchers – the systematic consideration of stakeholder opinion and evaluation of research outcomes being less common. Finally, a series of semi-structured interviews with senior heritage professionals explored their experience of collaborative research. The results identified key areas where strategic support is needed to promote user participation and enhance impact. These include training for research readiness, engagement, and impact for both researchers and users; better methods for needs and outcome assessment; affordable open access options and greater diversity of knowledge exchange opportunities. Finally, the need for ethical guidelines for responsible research, and greater emphasis on non-academic impact within research rating systems are discussed.  相似文献   
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