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1.
The concept of value is central to mineral economics as it is all branches of economics. In the minerals sphere particular problems are posed for a theory of value by, firstly, the non- renewability of mineral resources, secondly the substantial effort that must be made to convert a mineral into a useful product, and finally the perception of minerals, both economically and symbolically, as peculiarly national forms of wealth. Some thoughts are offered on different approaches to mineral resource valuation and on the frequently conflicting principles of exploitation to which these various approaches give rise.  相似文献   

2.
This article discusses the concept of public space management and its evolution in a context of wider changes to urban governance. Public space management is taken as a sphere of urban governance in which conflicting societal demands on, and aspirations for, public space are interpreted through a set of processes and practices. Four interlinked dimensions for public space management are proposed: the co-ordination of interventions; the regulation of uses and conflicts between uses; the definition and deployment of maintenance routines; and investment in public spaces and their services. Within this conceptual framework, the paper looks at recent changes in public space management in England to suggest the emergence of alternative models of management. These are based on the roles ascribed to the state, to private agents and to user organisations, and on different approaches to dealing with the four management dimensions. Although the discussion shows that these models are more than just abstract formulations, and have been used to deal with a variety of public space problems, an important purpose for the paper is to provide an analytical framework through which to examine emergent practices in the management of public space and their potential consequences.  相似文献   

3.
There are frequent suggestions that countries specializing in mineral and energy extraction have a type of growth that is bad for the poor. Others claim that extraction-led growth is particularly good for the poor. Both claims are made without the support of substantial empirical evidence. This paper uses longitudinal data on income growth by quintile in 57 developed and developing countries to statistically assess how mineral and energy extraction has affected the relationship between growth and the poor. We can find no evidence that the data support either the claim that extraction-led growth is good for the poor or that extraction-led growth is bad for the poor. This finding does not rule out that extractive activity can have special positive or negative impacts on the poor in some countries or regions. Rather, it simply brings to light that such effects are not evident as a persistent statistical phenomenon in the national level data that are available, which may be why the debate tends to move along without resolution.  相似文献   

4.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach.  相似文献   

5.
本文对国内外脱硫技术进行了综合性比较,分析了国内研究现状,同时对引进的脱硫工艺作了分析汇总,在此基础上,预测了脱硫技术在我国的应用前景,并就开展脱硫工艺提出相关建议。  相似文献   

6.
Hilkert Colby, Elizabeth J., Thomas M. Young, Peter G. Green, and Jeannie L. Darby, 2010. Costs of Arsenic Treatment for Potable Water in California and Comparison to U.S. Environmental Protection Agency Affordability Metrics. Journal of the American Water Resources Association (JAWRA) 46(6):1238–1254. DOI: 10.1111/j.1752-1688.2010.00488.x Abstract: The United States (U.S.) federal standard for arsenic in potable water systems is only the second water quality standard in which the U.S. Environmental Protection Agency (USEPA) administrator used “discretionary authority to establish a less stringent standard” based on the results of cost-benefit analyses. Based on the findings that a “standard of 3 μg/l would be feasible but not justified,” the revised maximum contaminant level (MCL) lowered the allowable arsenic concentration from 50 to 10 μg/l in 2002. In 2009, approximately 145 systems in California were out of compliance. The objectives were to gather performance and cost data from arsenic treatment systems in California to compare with data from the USEPA demonstration sites as well as with the USEPA affordability metrics for drinking water. The median cost of compliance with the revised arsenic MCL for the 36 surveyed systems was $1.95/1,000 gallons (2008 dollars), which is 69% of the average cost of delivered tap water in the U.S. in 2008 ($2.81/1,000 gallons). Additionally, 22% of the surveyed systems in California paid more than the maximum predicted cost of compliance with the revised arsenic MCL ($5.05/1,000 gallons). The largest variation in cost was seen in the systems that treated <500 gpm. For the systems utilizing adsorption, systems obtained between 20 and 80% of the expected bed volumes prior to breakthrough, indicating the need for better prediction of performance.  相似文献   

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