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971.
972.
Silver (Ag) is a precious metal of increasing importance. Besides its classical use as a valuable, it is applied in an increasing number of industrial products due to its advantageous chemical properties. As silver is considered a non-renewable resource, it is becoming more and more relevant for individual countries to gain a better understanding of their domestic silver material flows. In our study, a material flow analysis (MFA) of silver in Austria for the period 2012 was carried out, the results of which reveal the major silver flows in the country as well as the imports and exports outside the country. As there is no extraction of silver ore in Austria, the country is depending on silver imports and recycling. Furthermore, the role of the silver coin production that is of considerable importance in Austria is highlighted. The results may help, on a policy level, to determine silver use indicators and support the development of strategies for resource, waste and environmental management of silver. On a modeling level, the results may function as an example for future silver MFA studies in different countries. 相似文献
973.
我国陕西省榆林市、甘肃省白银市、辽宁省抚顺市及四川省古蔺县等地区,依托丰富的铜、煤炭、天然气等矿产资源带动了当地经济的快速发展。然而,对资源的过度依赖和开发,使地方经济无可回避地面临"资源诅咒"和"生态赤字"问题。本文在界定"资源诅咒"和"生态赤字"概念,及其产生的经济学根源的基础上,对"榆林市"、"白银市"等典型资源型城市的"生态赤字"现状予以分析,提出基于"3E系统模型"视角下,解决资源型城市"资源诅咒"和"生态赤字"问题,实现地方经济可持续发展的路径选择。 相似文献
974.
Spiros M. Karakostas 《Journal of Land Use Science》2016,11(5):595-617
The successful implementation of major development initiatives relies on the sound allocation of land uses against critical design criteria and constraints. The discovery of optimum development plans introduces severe complexities in formulating and solving the underlying multi-objective optimization problem. Moreover, in the presence of conflicting planning criteria decision-makers should be provided with a set of alterative-yet-optimum solutions that uniformly cover the spectrum of feasible maps. The introduction of sophisticated optimization algorithms addresses this challenge by pursuing a complete approximation of the Pareto front containing all prominent spatial allocations. This study demonstrates the effectiveness of a new evolutionary algorithm (UDT-MOEA) against the results of an established multi-objective genetic algorithm (NSGA-II) when applied on a major greenfield initiative against the optimum location(s), size and shape of three new land uses. Each algorithm performs best in different areas of the feasible objective space, providing planning alternatives with distinct characteristics. 相似文献
975.
An interval joint-probabilistic programming method for solid waste management: a case study for the city of Tianjin, China 总被引:1,自引:0,他引:1
Yi XU Shunze WU Hongkuan ZANG Guiguang HOU 《Frontiers of Environmental Science & Engineering》2014,8(2):239-255
Currently, environmental protection and resources conservation continue to be challenges faced by solid-waste managers in China. These challenges are being further compounded by rapid socioeconomic devel- opment and population growth associated with increased waste generation rates and decreased waste disposal capacities. In response to these challenges, an interval joint-probabilistic mixed-integer programming (IJMP) method is developed for supporting long-term planning of waste management activities in the city of Tianjin, which is one of the largest municipalities in the northern part of China. In the IJMP, joint probabilistic constraints are introduced into an interval-parameter mixed-integer programming framework, such that uncertainties presented in terms of interval values and random variables can be reflected. Moreover, a number of violation levels for the waste-management-capacity constraints are examined, which can facilitate in-depth analyses of tradeoffs among economic objective and system-failure risk. The results indicate that reasonable solutions have been generated. They are valuable for supporting the adjustment of the city's existing waste-management practices and the long- term planning of the city's waste-management facilities. 相似文献
976.
Mark Kammerbauer 《Disasters》2013,37(3):401-419
This paper examines a city and a natural disaster, specifically New Orleans, Louisiana, after Hurricane Katrina of August 2005. Recovery here is ongoing and the process of return is incomplete, with long‐term dislocation to other cities in the United States, such as Houston, Texas. The question arises as to how planning and stratification influence evacuation and return/dislocation and how they result in a particular practice of adaptation. This interrelated process is conceptually integrated and termed ‘schismo‐urbanism’ and is analysed within a multidimensional theoretical framework to evaluate aspects of urban sociology and natural disasters. Empirical research is based on a quantitative and qualitative mixed‐method case study. Data were collected during two rounds of field research in New Orleans and Houston in 2007 and 2009. As a comparative socio‐spatial study of affected and receptor communities, it makes a novel theoretical and methodological contribution to research on urban disasters in the context of continuing and rapid social change, and is targeted at disaster researchers, planning theorists and practitioners, and urbanists. 相似文献
977.
《Environmental Hazards》2013,12(3-4):291-310
This study uses multilevel regression analysis to examine the effect of social characteristics and the built environment on clearance time under an evacuation scenario. The primary unit of analysis is the US Census tract (N?=?1660), nested within 31 incorporated places spanning five US states. The dependent variable is an estimate of clearance time in hours derived using network analysis techniques within a geographic information system. We find that tracts with a more peripheral location, more female residents, a higher proportion of Hispanic residents, and higher median household incomes are associated with higher clearance times, on average. Our research suggests the relationship between suburbanization and clearance time is complex and evolving, mediated by past investments in the built environment and shifting social conditions. In addition to facilitating the evacuation of areas with low access to personal vehicles, urban planners and emergency management officials should also consider how the degree of connectivity in the street network impacts congestion and clearance time. 相似文献
978.
X. Wang 《国际发展与全球生态学杂志》2013,20(4):239-249
Based on the case study of Shenzhen Special Economic Zone, China, this paper investigates the theories and application of ecological planning for promoting urban sustainable development. The stated significance of such development is to promote the co-ordination of relationships between man and nature, and man and the environment. 相似文献
979.
H. Briassoulis 《国际发展与全球生态学杂志》2013,20(2):110-120
The central argument of the paper is that effective pollution prevention can be achieved only by integrated land-use planning which offers the broad framework for co-ordinating technological and non-technological means to achieve sustainable development. The paper first reviews the role of land-use in preventing or contributing to pollution over time, focusing especially on contemporary efforts to promote environmental protection through land-use planning and management. The relationship between land-use, pollution and sustainable development is analysed by examining the most important types of land-use-related problems, discussing their causes and identifying a number of land-use-related constraints to sustainable development. Finally, a land-use planning and policy framework approach to pollution prevention for sustainable development is outlined which emphasizes the need for integrated analysis of pollution problems and adoption of comprehensive approaches to their solution. Scientific, spatial, temporal and policy issues are addressed in the context of the proposed approach. 相似文献
980.
Because of the expanding population in our cities with its demands for more diversified services, we cannot afford a piecemeal type of urban underground growth. Utilization of the urban street system for buried utilities has a serious adverse effect on other street functions because of the continuing necessity to perform excavations for the repair of existing lines and the installation of new ones. The excavations not only are a serious cause of traffic delay and congestion but also create noise and aesthetic disturbances, and result in excessive street maintenance requirements and in shortened overall street life. Consider the enhancing effects in quietness on abutting properties and users of the street, and the benefits become very great. Unfortunately, the lack of data and the difficulty in quantifying the intangibles have made it impossible to arrive at a reasonably accurate figure of overall negative impact on the urban environment of street cuts. However, if drivers are sufficiently strong to merit the use of utility tunnels, then sustainable municipal policies improving living quality will be implemented. 相似文献