ON THE SEISMIC VULNERABILITY OF EXISTING UNREINFORCED MASONRY BUILDINGS

A large part of the building population in Switzerland is made of unreinforced masonry. For the assessment of the seismic risk the evaluation of the seismic vulnerability of existing unreinforced masonry buildings is therefore crucial. In this paper a method to evaluate existing buildings, which was developed for the earthquake scenario project for Switzerland, is briefly introduced and discussed in more detail for unreinforced masonry buildings. The method is based on a non-linear static approach where the seismic demand on the building is compared with the capacity of the building. In-plane and out-of-plane behaviour are considered. Comparisons with test results from model buildings show that the proposed method suitably forecasts the capacity of a building. Finally, a numerical example of the application of the method to a building in the city of Basel is given.     

INFLUENCE OF CAPACITY DESIGN METHOD ON THE SEISMIC RESPONSE OF R/C COLUMNS

Abstract

This paper aims at assessing the influence of the design procedure followed in designing the columns of a reinforced concrete (R/C) building on the performance of the columns, aa well as of the structure as a whole, when subjected to seismic loading; to identify potential weaknesses in currently adopted procedures; and to present a new procedure which is based on currently-available, powerful analytical tools, and results in increased reliability with regard to seismic loading. Two case studies are presented, involving multistorey reinforced concrete buildings with frame and dual structural systems subjected to various appropriately-scaled input accelerograms. The results obtained indicate that capacity design of columns results in adequate safety margins against failure, even when the adopted overstrength factors are quite low, but hinging in columns is not avoided unless very high overstrength factors are used. The suggested novel technique of capacity design led to very satisfactory seismic performance, and offers the possibility of cost reduction by achieving an appropriate balance between provided flexural strength and corresponding confinement.     

The Nigerian oil palm industry

Some 10,000 years ago with the disappearance of the last Devensian ice, the climate of the British Isles began a slow but general warming. This continued until the middle of the fifteenth century when the Little Ice Age developed, ushering in several centuries of colder weather and violent fluctuations in weather associated with the expansion of the circumpolar vortex. Detailed information of the effect on Scotland's weather of this major climatic disturbance is rare but The Chronicle of Fife written in the seventeenth century by John Lamont does provide some remarkable insights.     

百年来“春秋决狱”研究的突破性进展

百年来关于“春秋决狱”的研究,成果卓著。学者们不懈地努力,丰富了我们的学术视野。收集这些零散的学术观点,进行归纳整理,肯定成绩,找出问题,无疑会为以后的研究奠定良好的基础。     

Resource and environmental management: connecting the academy with practice

The rewards and challenges related to a research program that involves interactions between basic and applied research are shared. Specific experience is examined regarding integrated water resource management, capacity enhancement in developing countries and writing textbooks. Key lessons include the manner in which applied research and practice inform and enhance basic research, the role of theoretical and conceptual frameworks in guiding applied research, the need to understand the distinction between multidisciplinary and interdisciplinary models and the importance of facilitating evolution from visions, strategies and plans to action.     

Screening Climatic and Non‐Climatic Risks to Australian Catchments

Emerging and future climatic change across the Australian continent has been identified as a significant threat to the successful sustainable management of the nation's water resources. However, the impacts of climate change must be viewed within the context of past, present and future climatic variability and human agency. A qualitative screening‐level risk assessment was undertaken for Australia's 325 surface water management areas by aggregating a suite of six relevant risk indicators. Four indicators addressed the antecedent conditions upon which future climate change will act. These included 50‐year trends in rainfall, the status of surface and groundwater development, and catchment condition. Two indicators addressed future drivers of supply and demand; specifically, projected changes in runoff and population. The results indicate that the management challenges currently experienced in Australia's population centres and key agricultural areas such as the Murray‐Darling Basin are likely to increase in future decades. Furthermore, the geographic distribution of net risk, inclusive of multiple biophysical and socioeconomic drivers, is more extensive than is suggested by consideration of surface water development and availability alone. Comparison of at‐risk catchments with the spatial distribution of various social and environmental assets identified a high degree of overlap among catchment risk and human populations, water storages, irrigated agricultural land, and wetlands of international significance. This suggests that the catchments of the greatest value are also those judged to be at greatest risk. Though considerable work remains in evaluating the security of Australia's water resources to climatic and other stressors, this study provides a first‐order scheme for prioritising the risks to which catchments are exposed and an assessment of how some key drivers are likely to interact to drive risk.     

中国计划经济的重新审视与评价

中国经济体制在20世纪的后50年里,就经济运行来说,经历了一个由计划与市场并存向计划经济转变、再由计划经济向市场经济转变的螺旋式发展过程。中国在50年代之所以选择计划经济体制,除主观认识因素外,当时的工业化压力、资源短缺和政府动员能力强也是重要因素。计划经济体制形成后的20年里,尽管它在集中资源加快独立工业体系的建立方面发挥了重要作用,并基本保持了高积累下的社会稳定,但是它最大的缺陷是不能长久实现社会主义所追求的高效率,而这正是计划经济被社会主义市场经济所取代的真正原因。     

百年来的"春秋决狱"研究评析

百年来关于“春秋决狱”的研究,成果卓著,学者们为此而付出了不懈地努力。笔者收集这些零散的学术观点和相关资料,进行归纳整理,对其肯定成绩,找出问题,意在为以后的研究选准突破口,奠定良好基础。     

关于我国旅游业国际竞争力的思考

研究旅游业国际竞争力具有十分重要的意义。本用波特国家竞争优势理论对我国旅游业国际竞争力现状进行了分析,认为我国旅游业虽具有某些优势,但现有的国际竞争力较弱。同时,作认为研究旅游业国际竞争力应具有多相测度。     

THE CONCEPT OF CRITICAL ENVIRONMENTAL ASSESSMENT (EA) EDUCATION

The paper explores the role of education in environmental assessment (ea), identifies the range of techniques used to conduct ea education, and develops a rationale for the concept of critical ea education. The literature on public involvement in ea indicates that public education plays a significant, but poorly defined, role in current thinking on public involvement and reveals a diverse range of education techniques. To clarify the role that education can potentially play in the ea process, consideration of the theories of critical pedagogy and transformative learning led to the concept of critical ea education. Empirical support for critical ea education is presented through consideration of the recent Manitoba ea case involving the Pembina Valley Water Supply System. Nonparametric statistical analysis of variables at work in the Pembina Valley case reveal strong correlations that support the principles of critical ea education. Cette communication explique le rôle que l'gducation joue dans l'haluation de I'environnement (EE), elle identifie la gamme de techniques utilisées dans cette éducation, et elle développe un raisonnement pour le concept de l'importance de l'gducation dans l'EE. La littgrature qui traite le rdle du public dans l'EE indique que l'gducation publique joue un rôle important, mais mal défini, dans la penske courante au sujet de la participation du public dans DE. Cette littgrature révde ggalement toute une gamme de techniques pgdagogiques. Afin de mettre à jour le rôle que l'gducation pourrait jouer dans 1'EE, une considgration des théories de l'gducation critique et de l'apprentissage de la transformation a abouti au concept de l'importance de l'éducation dans 1'EE. Nous présentons en tant qu'appui empirique de l'importance de l'gducation dans l'EE une discussion du cas récent au Manitoba qui concerne le Système deau de la vallée Pembina. Une analyse statistique non-parametrique des variables qui jouent un rôle dam ce cas révélent dimportantes corrdations qui servent à appuyer les principes de l'importance de l'bducation dans 1'EE.