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231.
Anticipated climate policies are ineffective when fossil fuel owners respond by shifting supply intertemporally (the green paradox). This mechanism relies crucially on the exhaustibility of fossil fuels. We analyze the effect of anticipated climate policies on emissions in a simple model with two fossil fuels: one scarce and dirty (e.g. oil), the other abundant and dirtier (e.g. coal). We derive conditions for a ‘green orthodox’: anticipated climate policies may reduce current emissions. The model can also be used to analyze spatial carbon leakage. Calibrations suggest that intertemporal carbon leakage (from 0% to 8%) is a relatively minor concern.  相似文献   
232.
We study how government green procurement policies influence private-sector demand for similar products. Specifically, we measure the impact of municipal policies requiring governments to construct green buildings on private-sector adoption of the US Green Building Council?s Leadership in Energy and Environmental Design (LEED) standard. Using matching methods, panel data, and instrumental variables, we find that government procurement rules produce spillover effects that stimulate both private-sector adoption of the LEED standard and investments in green building expertise by local suppliers. These findings suggest that government procurement policies can accelerate the diffusion of new environmental standards that require coordinated complementary investments by various types of private adopter.  相似文献   
233.
492Q发动机分层进气燃烧净化节油系统的研究,是为了使国产492Q发动机的油耗水平下降,同时也降低其排放对大气的污染。为此,采用稀薄燃烧原理,使发动机在空燃比(AF)为18左右也可正常燃烧,达到降低油耗,同时也减少了CH、CO、NO_x的排放。   相似文献   
234.
Cut-off grade is defined as the grade which discriminates between ore and waste within a given orebody. Determination of a complete optimum cut-off grade policy is a very important function during mine life. Using the modified optimum cut-off grade model presented in this paper not only the net present value of a porphyry copper mining project is maximized, but also the adverse environmental impacts of the project are minimized simultaneously. This methodology is more effective in long-range planning. For showing the effectiveness of the model, two scenarios are considered in a hypothetical deposit and the results show that incorporating the modified optimum cut-off grade policy, the net present value will be increased by 3.6% in comparison with the Base Case.  相似文献   
235.
This, our second reply to Östensson, supplements our earlier more technical analysis with a simple intuitive explanation of how investor demand can be driving commodity prices higher even when investor stocks are falling.  相似文献   
236.
In the mining sector, local communities have emerged as particularly important governance actors. Conventional approaches to mineral development no longer suffice for these communities, which have demanded a greater share of benefits and increased involvement in decision making. These trends have been spurred by the growth of the sustainable development paradigm and governance shifts that have increasingly transferred governing authority towards non-state actors. Accordingly, there is now widespread recognition that mineral developers need to gain a ‘social license to operate’ (SLO) from local communities in order to avoid potentially costly conflict and exposure to social risks. A social license can be considered to exist when a mining project is seen as having the ongoing approval and broad acceptance of society to conduct its activities. Due to the concept's relatively recent emergence, however, only a limited body of scholarship has developed around SLO. Drawing on examples from northern Canada, this paper uses governance and sustainability theories to conceptualize the origins of SLO in the mining sector and describe some of the associated implications. Further research is needed to determine governance arrangements which help facilitate establishment of SLO in different mineral development contexts.  相似文献   
237.
In order to better manage artisanal and small-scale gold mining, the Burkinabe authorities have planned to build a suitable methodological support as an aid to elaborating appropriate policies and actions. The developed methodology concerns (a) at a spatial level, the generation and analysis of a geological resources map needed by the artisanal miners and (b) at a socioeconomic level, analysis of the miners' activity. This paper reports and discusses the results of our suggestion to also introduce the use of an approach known as multi-agent system (MAS) as a complementary part of this initial methodology, at a downstage level to the above two analysis stages. MAS methodology could be used to develop simulation models to forecast the future of the activity. MAS is appropriate for describing the dynamics of systems where it is impossible to obtain all output data of a model from a purely mathematical or statistical transformation of input data. Our suggestion involves (i) demonstrating the capacity of the approach to simulate all parameters needed by mining policy makers and (ii) evaluating to what extent the methodology is accepted by them, as well as, at a more scientific level, the literature regarding mining system simulation.  相似文献   
238.
This paper argues that the current formalization system for small-scale gold miners in Ghana has been undermined and the small-scale mining laws no longer capture the reality of the sector’s activities. The paper will examine the small-scale mining system and shows that registered and unregistered actors operate not only in parallel but are actually intertwined and highly dependent on one another. The paper shows that the perceived dichotomy of formal and informal actors in the sector does not actually exist. The sector has instead evolved into a highly intertwined group of semi-formal sectors operating with varying degrees of legal registrations. The paper concludes that political leniency and law enforcement corruption has resulted in a booming small-scale gold system under poor government control. The paper recommends that politicians move to enact reforms to regularize the small-scale mining sector and curtail ubiquitous environmental and occupational safety problems. Anti-corruption initiatives and law enforcement reforms are the most urgent. However, reforming the laws is also necessary to capture and regulate the technological innovations the sector is currently using.  相似文献   
239.
Over the last fifteen years, large-scale mining companies have started engaging in Corporate Social Responsibility (CSR), with the aim of contributing to developing local communities affected by their operations. Large-scale mining companies, together with the World Bank, have formulated voluntary principles and benchmarks to guide these company–community relations. Recently, it has been argued that CSR is also crucial in the early stages of exploration. Nowadays, mining consultants propagate a process approach to company–community relations, from early exploration to post-mining planning.  相似文献   
240.
Since the liberalisation of its investment regime in the 1990s, Argentina has seen a rise in foreign direct investment into large-scale exploration and exploitation of mineral resources. However, many social groups (local communities, grassroots movement and the church) often strongly oppose new mining projects on the grounds of environmental, ethical and economic concerns. In a situation marked by widespread conflict, mining companies continue operating and develop Corporate Social Responsibility (CSR) initiatives which are often promoted as a means of contributing to the sustainability and development of the nation. The paper develops a framework to highlight how the principles of stakeholder theory could be used as conceptual and practical guidance for conflict-resolution oriented CSR policies. The framework is further used to analyse two case studies of conflictive mining projects in Argentina. The paper explores how key stakeholders perceive contribution of CSR to welfare and the socio-economic development of mining communities and sustainable development of the nation. It demonstrates that institutional and social stakeholder networks often strongly oppose the idea of voluntary self-regulation implied by CSR in situations characterised by weak governance. Even though the CSR of companies could be improved in areas of corporate communication, transparency, stakeholder engagement and dialogue, it is not seen as a panacea for the social conflicts in the sector.  相似文献   
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