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991.
Robert Mier Wim Wiewel 《Journal of the American Planning Association. American Planning Association》2013,79(3):316-325
All over the country community organizations are starting new community based businesses designed to fight unemployment, generate needed income, or respond to their own growth needs. This article addresses the questions of whether these new approaches can be used to plan and implement economic development efforts, what their political and ideological content is likely to be, what impact they will have on their neighborhoods, and what roles planners can play. The analysis is based on the authors' experiences as planners and technical assistants to such efforts, and on a detailed analysis of case studies. 相似文献
992.
Robert Lowe 《Building Research & Information》2013,41(3):159-175
The magnitude and implications for the construction industry of reductions in carbon dioxide emissions that will ultimately be required globally and in industrialized countries are critically examined. As a result of the problem of climate change, these reductions are found to be in the region of 80–90% by 2050- much larger than those presently under discussion in national and global political fora. The technological feasibility of buildings with low energy requirements and low carbon emissions suggests that existing technology is capable of delivering reductions in this range. Unfortunately, the progress that is being made at the cutting edge is, with very few exceptions, not carried over into building stocks as a whole. Regulatory, fiscal and market-based policy and strategy mechanisms for improving the performance both of new build and the existing stock are critically examined. The achievement of meaningful reductions will require a coordinated and strategic approach, which makes use of the complementarity between these mechanisms. Regulation alone, in the absence of clear and consistent price signals provided through mechanisms such as carbon taxation, is unlikely to deliver the reductions in carbon emissions that will be needed to stabilize the global atmosphere and climate. L'ampleur et les implications pour l'industrie de construction des réductions des émissions de dioxyde de carbone qui seront généralement exigées en fin de compte font l'objet d'un examen critque dans les pays industrialisés. Suite au problème des changements de climat, on a trouvé qu'en 2050 ces réductions d'émissions devraient se situer dans une zone de 80 à 90 % - c'est à dire, beaucoup plus grands que celle qu'on trouve dans les discussions et symposiums politiques nationaux et mondiaux. La faisabilité technologique de constructions nécessitant peu d'énergie et à faible émission de carbone suggére que la technologie actuelle est capable d'apporter des solutions à ces réductions. Malheureusement, à de rares exceptions prés, les progrés qui sont faits dans ces domaines de pointe ne sont pas appliqués dans leur totalité au secteur du bâtiment. La politique coordinatrice et fiscale, basée sur le marché ainsi que les mécanismes stratégiques visant à améliorer les performances concernant aussi bien les nouvelles constructions que celles existantes, sont examinés d'une façon critique. L'obtention de réductions significatives exigera une approche coordonnée et stratégique mettant en oeuvre ces deux mécanismes complémentaires. La seule réglementation, en l'absence d'arguments de prix clairs et cohérents comme par exemple la taxation sur l'oxyde de carbone, ne va vraisemblablement pas entrâner les réductions d'émissions de gaz carbonique qui seraient nécessaires afin de stabilizer l'atmosphère et le climat au niveau mondial. 相似文献
993.
Robert Home 《Planning Perspectives》2013,28(3):365-373
Self‐help housing in peri‐urban areas (usually outside municipal boundaries) is a feature, not only of rapidly urbanizing countries now in the South, but was also in Victorian England, where it was often initiated by freehold land societies, created by the Chartist movement in order to expand the franchise. These bodies bought and subdivided land for sale to their members, and laid out roads, using legal powers conferred upon the building societies. The societies made a significant contribution to housing for the urban working class, and preceded the garden city and town planning movement promoted by Liberal politicians. A case study is presented of one successful provincial society, the Ipswich and Suffolk Freehold Land Society. 相似文献
994.
995.
Robert B. Black 《Journal of the American Planning Association. American Planning Association》2013,79(3):28-35
Abstract A SYMPOSIUM OF CURRENT PLANNING THEORY: Planning for America , By GEORGE B. GALLOWAY AND ASSOCIATES. Henry Holt and Co., New York; 713 pages, price $3. A TEXTBOOK ON SUBDIVISION: Subdivision Regulations: An Analysis of Land Subdivision Control Practices. By HAROLD W. LAUTNER. Public Administration Service; 346 pages, price $3.75. EMPLOYMENT IN THE REGIONAL DEVELOPMENT OF RESOURCES: Development of Resources and Stabilization of Employment in the United States. By THE NATIONAL RESOURCES PLANNING BOARD; 409 pages, price $1.20. 相似文献
996.
Robert Freestone 《Planning Perspectives》2013,28(1):11-15
Sir Peter Hall passed away at the age of 82 in July 2014. As a leading figure in the fields of planning, geography, urban regeneration, regional studies and transportation, numerous tributes and obituaries have already been published. In this memoir, Associate Editor Rob Freestone draws from his essay in the 2014 book which he co-edited with Mark Tewdwr-Jones and Nicholas Phelps, entitled The Planning Imagination: Peter Hall and the Study of Urban and Regional Planning (2014), to reflect on Peter's approach and contributions to the study of planning history. 相似文献
997.
A new approach to modelling probabilistic and stochastic engineering systems using graph theory is outlined. This approach emphasizes the introduction of probabilistic and stochastic concepts at the very beginning of the model building process. This is in marked contrast to past tendencies to add probabilistic concepts to the end of an otherwise deterministic model building process. The development of topological models founded on oriented probabilistic measurements is given. which leads to the identification of some useful statistical properties of the’ random interconnection equations’. The development of probabilistic component models is given, where a component can be characterized independently of other components. Methods for automatically building the second moment representation of the Mixed Nodal Tableau are discussed. The application of the above theory to the probabilistic analysis of a pipe network problem is briefly described. 相似文献
998.
Robert Hrelja 《Planning Theory & Practice》2013,14(4):511-524
Though new goals for sustainable cities and transport systems have been developed, decisions and planning at a local level often fail to achieve these ambitions. The purpose of this article is to analyse the factors in local decision-making and planning practice that conduce to urban sprawl and increased car traffic. The article analyses how the conscious application of so-called “day-to-day decision-making and planning”, results in a diminution of planning's role as a strategic tool, in concealment of the environmental impact of increased traffic, in the deprioritization of environmental goals in favour of growth, and in the “tyranny of small decisions”, where the need to make many individual decisions distracts from the achievement of sustainable city and transport systems. Day-to-day decision-making and planning are analysed and described in a case study centring on retail trade on the outskirts of the Swedish town of Örebro. 相似文献
999.
Matthew W. Liberatore Brittany N. Peterson Theresa Nottoli Joshua M. McCulloch Robert E. Jinkerson Nanette R. Boyle 《分离科学与技术》2016,51(5):892-898
A method to flocculate algal cultures of Chlamydomonas reinhardtii using four different industrially produced polymers is presented. Starting with a 1 wt% stock polymer solution, flocculation times less than 60 min were observed for 0.1 to 0.6 g polymer per L of algae culture, while control samples took greater than 1400 min to flocculate. Cell counts showed that 99% of the cells were flocculated using the polymers compared to 73% for the control. Finally, the flocculation process was successful at both 5 and 40 mL batch sizes for one polymer; therefore, the method is efficient, effective and may be scalable. 相似文献
1000.
Effects of ultrahigh speed twin screw extrusion on the thermal and mechanical degradation of polystyrene 下载免费PDF全文
Azadeh Farahanchi Robert Malloy Margaret J. Sobkowicz 《Polymer Engineering and Science》2016,56(7):743-751
This article characterizes a novel twin screw extrusion (TSE) process with the capability of rotating at speeds up to 4500 rpm. The resulting extreme high shear rate is expected to result in molecular weight changes due to thermomechanical degradation of the polymeric materials being extruded, polystyrene (PS) in this case. In order to differentiate between mechanical and thermal factors affecting degradation of PS running at ultrahigh speeds and also to evaluate the relative importance of the two mechanisms, PS has been extruded at different screw speeds and different barrel temperatures with corresponding melt temperatures. Viscosity measurements and size exclusion chromatography measurements show the extent of degradation due to mechanical stress as a result of high screw rotational speeds. Furthermore, through analyzing the kinetics of PS depolymerization, the reaction rate and hypothetical apparent temperatures at each screw speed have been calculated. All results support the idea that the mechanical shear stress can be considered as the controlling factor of polymer degradation in ultrahigh speed TSE. POLYM. ENG. SCI., 56:743–751, 2016. © 2016 Society of Plastics Engineers 相似文献