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21.
The theme of a more compact city has been a central feature of planning policy for Sydney's development over the last two decades. Urban consolidation, in the form of attached dwellings in medium- and high-density configurations, has become the predominant form of new residential development since the early 1990s. One of the largely untested claims for this policy is that it provides more housing choice for an increasingly diverse population and that simply building larger amounts of smaller housing in high-density concentrations will be sufficient to meet that demand. As a result, planning for higher density housing has been undertaken with little explicit recognition of the housing sub-markets higher density housing caters for or their specific spatial characteristics within the city. These issues are examined by an analysis of the socio-economic characteristics of areas with high concentrations of attached housing. These data are processed by factor analysis to identify and locate the range of sub-markets within attached housing and additional small area data used to fill out the market profiling. The results reveal that a range of specific housing needs are met by this form of housing with discriminative characteristics in certain locations. In other words, higher density housing is associated with a range of locationally specific and spatially distinctive sub-markets. These findings are particularly relevant and timely as a new metropolitan strategy is in preparation for Sydney where an estimated 60–70 per cent of new dwelling provision in the next 30 years will take place within existing suburbs through higher density redevelopment. Planning for such development must take into account the local markets for such accommodation which have very different characteristics in different parts of the city. 相似文献
22.
多病床非典病房的气流分布研究 总被引:2,自引:0,他引:2
到2003年8月7日止,在全球34个国家和地区相继出现了严重急性呼吸系统综合症(SARS或者非典),其中,共报告有8422例疑似案例,916例死亡案例。2002年11月到2003年6月间的非典流行中,医院医护人员受感染情况最为严重,世界范围内20%的感染群体为医护人员,香港地区22%的确诊案例为医护人员。因此,为减少交叉感染,加强有关工程控制,特别是在非典病房里进行通风设计是非常必要的。本文总结了非典病房气流分布的最新研究。这项研究由非典特工队于2003年4~7月间完成。非典特工队是由香港工程师协会组织,来自7个专家协会的工程师组成的研究小组。在对香港治疗非典医院的现有空调系统进行了解后,非典特工队首先运用计算流体力学模拟确定了在6个床位的病房里减少交叉感染和改善污染物稀释的通风设计;接着,对新设计在香港大学屋宇设备实验室里的全尺寸非典病房里进行了测试。测试表明,新设计方案在这个接近现实的全尺寸非典病房里运行良好。采用床头回风口回风设计可有效地对病人产生的含病毒颗粒进行局部捕获。根据这项研究,作者提出了原则性的设计建议。2003年里,香港政府和医院管理局医院采纳了非典特工队提出的设计基本原理建造了1200多个床位的可用于非典治疗的新病房。另外,气流分布是复杂的紊流过程,送风格栅结构如导流器或散流器的微小改动以及送风参数如风速、温度和风向的微小变化都会引起气流的改变。适当的设计对于减少病人间、病人与医护人员之间的交叉感染以及有效稀释和排除含病菌颗粒都是至关重要的。 相似文献
23.
This paper has the objective of improving on the issue of forecasting new housing construction, and highlights differences between space demand and investment demand in housing markets. Further, it indicates how these differences will affect construction decisions. The first step is to identify the factors associated with estimating residential property prices in Hong Kong, based on a demand-supply adjustment process. Specifically, this study examines the role of population growth, transaction volume, inflation and interest rate in determining house prices. Second, based on these estimations, a methodology is developed to estimate the investment demand schedule and new construction of residential property. 相似文献
24.
S. Herbert Hare Sir Raymond Unwin 《Journal of the American Planning Association. American Planning Association》2013,79(1):20-22
When We Build Again. A Bournville Village Trust Research Publication. George Allen &; Unwin, Ltd., London, 1941. Pp. xii (16), 138. Report Relative to Postwar Reconstruction in the City, Prepared by Improvements and Town Planning Committee, published by The Corporation of London, 1944, pp. 66 plus maps and photographs. The Economic Status of the New York Metropolitan Region in 1944, by The Regional Plan Association, Inc., New York, 1944, xx, 91 pp. 相似文献
25.
Sir Raymond Unwin 《Journal of the American Planning Association. American Planning Association》2013,79(2):37-39
The Economic Reports of The President, January 1948, January 1947 and July 1947. With an Introduction by the Council of Economic Advisors. Reynal &; Hitchcock, New York. 307 plus xiv pages. $2.50. The Master Highway Plan for the Boston Metropolitan Area. By The Joint Board for the Metropolitan Master Highway Plan, Charles A. Maguire &; Associates, De Leuw, Cather &; Co., and J. E. Greiner Co., Consultants, Boston. Feb. 1948. 121 pages and key maps. A Critical Review of Research in Land Economics. By Leonard A. Salter, Jr. The University of Minnesota Press. 1948. 258 pages. $4.00. Land Economics. By Roland R. Renne Harper and Brothers. 1947. 736 pages. $5.00. The Redevelopment of Central Areas. The Ministry of Town and Country Planning. H. M. Stationery Office, London, 1947. 99 pages, illustrated in color. Obtainable in the U.S.A. through the British Information Services, Rockefeller Center, New York. $3.65. Pierre Sur Pierre, Construction du Nouvel Urbanisme. By Gaston Bardet. Plans, photographs, diagrams. Editions L. C. B. Section Batiment, Paris, 1946-47. 290 pages. Planificacion y Sociografia. By Dr. Miguel Figueroa Roman, Instituto de Sociografia, Colegio Libre de Estudios Su-periores, Tucuman, Argentina, 1946. 201 pages. 相似文献
26.
Raymond Bunker 《Planning Perspectives》2013,28(1):59-80
The theory and principles of systematic colonization, propounded most strongly by Edward Gibbon Wakefield, set new rules for British expansion overseas after 1830. This was particularly apparent in the foundation years of South Australia after 1836, and in the early settlement of New Zealand after 1840 in which Wakefield played a personal part. These outworkings developed strong and distinctive town planning themes in which two South Australian Surveyors‐General, William Light and George Goyder figured prominently. The annexation of the Northern Territory of Australia in the 1860s and 1870s, and the expansion of the frontier of settlement in inland South Australia from 1860 to 1890 displayed these themes. This history demonstrates a breadth of concerns in the settlement of these territories which covers political economy; capitalist enterprise; the machinery of government and public policy concerning the survey, sale and use of land; the development of an urban system; and the planning of towns. This has not only left a strong imprint on the landscape but has left some influence on attitudes regarding land and property and on the style of government administration. 相似文献
27.
A key notion in regenerative design is the co-evolutionary, partnered relationship between socio-cultural and ecological systems, which requires an explicit engagement with the implications and consequences of future design decisions. However, despite the extensive literature in other disciplines regarding the co-evolution of socio-cultural and ecological systems, this approach has yet to receive serious scrutiny within the context of the built environment and within the emerging notions of regenerative development and design. Drawing on an interdisciplinary body of literature, a discussion is initiated on how socio-cultural and ecological systems and their co-evolution might connect to the concept of regenerative design. Following a critique of a relevant example highlighting the current practice of regenerative design, the new building for the Centre for Interactive Research on Sustainability at the University of British Columbia, Vancouver, potentially relevant aspects of a socio-ecological system and of evolution theories are examined for the built environment. Several observations are presented on how these may offer a stronger theoretical framing of regenerative design, particularly the shifts in design thinking: from buildings as artefacts to their dynamic role in adaptive processes over time; widening the boundary focus of a building from its site to the neighbourhood. Une notion clé du design régénérateur est la relation coévolutionnaire de partenariat entre les systèmes socioculturels et écologiques, ce qui nécessite un engagement explicite à l'égard des implications et des conséquences des futures décisions en matière de design. Cependant, malgré la vaste littérature existant dans les autres disciplines concernant la coévolution des systèmes socioculturels et écologiques, cette approche doit encore faire l'objet d'un examen sérieux dans le contexte de l'environnement bâti et sous l'angle des notions émergentes de développement et de design régénérateurs. En s'appuyant sur un corpus interdisciplinaire de publications, une discussion est amorcée sur la manière dont les systèmes socioculturels et écologiques et leur coévolution pourraient être reliés au concept de design régénérateur. Après une critique portant sur un exemple pertinent mettant en évidence les pratiques actuelles du design régénérateur, le nouveau bâtiment du Centre de Recherche Interactive sur le Développement Durable de l'Université de Colombie Britannique, à Vancouver, sont examinés les aspects potentiellement pertinents d'un système socioécologique et des théories évolutionnistes, s'agissant de l'environnement bâti. Plusieurs observations sont présentées quant à la manière dont ceux-ci peuvent offrir un cadre théorique plus solide au design régénérateur, concernant en particulier les changements intervenant dans la façon de penser le design : des bâtiments envisagés en tant qu'artéfacts à leur rôle dynamique dans les processus adaptatifs au fil du temps, et un bâtiment dont les limites ne se focalisent plus sur son site, mais sont élargies à son quartier. Mots clés: environnement bâti, coévolution, cadres conceptuels, évolution, design régénérateur, systèmes socioécologiques 相似文献
28.
29.
The 2009 Passive and Low Energy Architecture Conference (PLEA), held in Québec City, Canada, was themed ‘Architecture, Energy and the Occupant's Perspective’, with the ambition of positioning building inhabitants as key ‘active’ determinants of energy performance in ‘passive’ design through adaptive opportunities. Conference delegates committed to a Manifesto that embodied both the key longstanding priorities of PLEA and explicitly conveyed the priorities of the conference hosts. The Manifesto is examined in terms of how it captures and represents a shift in thinking that has occurred over the past few years, away from technological and technocratic solutions to comfort provisioning and towards reframing building energy consumption as a social and ethical challenge in which comfort plays a key role. La Conférence 2009 sur l'Architecture Passive et Basse Energie (PLEA), qui s'est tenue à Québec, au Canada, avait pour thème « Architecture, Energie et la Perspective de l'Occupant », avec pour ambition de positionner les habitants d'immeubles comme principaux déterminants « actifs » de la performance énergétique dans un design « passif » par des opportunités d'adaptation. Les délégués de la conférence se sont engagés en faveur d'un Manifeste qui, tout à la fois, incarne les principales priorités qui sont depuis longtemps celles des Conférences PLEA et traduit explicitement les priorités des hôtes de la conférence. Cet article examine le Manifeste quant à la manière dont il appréhende et reflète le changement intervenu au cours de ces dernières années dans la manière de voir les choses, consistant à se détourner d'un confort fourni par des solutions technologiques et technocratiques et à aller dans le sens d'un recadrage de la consommation énergétique des immeubles considérée comme un défi social et éthique dans lequel le confort joue un rôle clé. Mots clés: comportement adaptatif, agence, confort, fourniture du confort, qualité environnementale intérieure, habitants, manifeste, Conférence sur l'Architecture Passive et Basse Energie (PLEA) 相似文献
30.
Hydrogen and methane production from household solid waste in the two-stage fermentation process 总被引:13,自引:0,他引:13
A two-stage process combined hydrogen and methane production from household solid waste was demonstrated working successfully. The yield of 43 mL H(2)/g volatile solid (VS) added was generated in the first hydrogen production stage and the methane production in the second stage was 500 mL CH(4)/g VS added. This figure was 21% higher than the methane yield from the one-stage process, which was run as control. Sparging of the hydrogen reactor with methane gas resulted in doubling of the hydrogen production. pH was observed as a key factor affecting fermentation pathway in hydrogen production stage. The optimum pH range for hydrogen production in this system was in the range from 5 to 5.5. The short hydraulic retention time (2 days) applied in the first stage was enough to separate acidogenesis from methanogenesis. No additional control for preventing methanogenesis in the first stage was necessary. Furthermore, this study also provided direct evidence in the dynamic fermentation process that, hydrogen production increase was reflected by acetate to butyrate ratio increase in liquid phase. 相似文献