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991.
The Contribution of Bioenergy to a New Energy Paradigm   总被引:1,自引:0,他引:1  
Biomass is a widely available resource that is receiving increased consideration as a renewable substitute for fossil fuels. Developed sustainably and used efficiently, it can induce growth in developing countries, reduce oil demand, and address environmental problems. The potential benefits include: reduction of greenhouse gases, recuperation of soil productivity and degraded land, economic benefits from adding value to agricultural activities and improving access to and quality of energy services. The production of bioenergy involves a range of technologies, including solid combustion, gasification, and fermentation. These technologies produce energy from a diverse set of biological resources - traditional crops, crop residues, energy-dedicated crops, dung, and the organic component of urban waste. The results are bioenergy products that provide multiple energy services: cooking fuel, heat, electricity and transportation fuels. It is this very diversity that holds the potential of a win-win-win for the environment, social and economic development. Bioenergy has to be viewed not as a replacement for oil, but as an element of a portfolio of renewable sources of energy. Coherent and mutually supportive environmental and economic policies may be needed to encourage the emergence of a globally dispersed bioenergy industry that will pursue a path of sustainable development.  相似文献   
992.
The share of raw milk meeting fluid quality (Grade A) standards in the United States rose steadily through the latter half of the twentieth century, but a shrinking portion of that was used in fluid products. Grade A milk exceeds the quality standards for the manufactured products for which it has been increasingly used. We present an econometric model that exploits regional and temporal variation in policy implementation to identify the effect of marketing orders on the Grade A share of milk. Results support the hypothesis that marketing orders significantly encouraged the growth in the Grade A share of milk.  相似文献   
993.
994.
This study examines the deliberations of professional MBA students when presented with a dilemma that weighs the difference between commitments to profit- maximization against concerns for fired workers who would need to seek a new job during a recession. Using content analysis, accounting, economic, and ethically based rationales that differ from the profit-maximizing recommendation are categorized. Results also show that those who make non-profit-maximizing recommendations consider, but ultimately reject the profit-maximizing approach to layoffs.  相似文献   
995.
The emergence of new industries is an important phenomenon that remains relatively neglected by researchers. We address several theoretical and methodological problems that impede the study of emerging industries. In doing so, we propose that historical archives represent a critical and under-utilized research resource. More generally, we contend that advancing the study of emerging industries will require scholars to develop several distinct categories of research, to make more extensive use of qualitative and historical data, to collaborate across traditional boundaries of domain and method and to engage key practitioners, including professional archivists and institutional entrepreneurs.  相似文献   
996.
Motivated by numerical representations of robust utility functionals, due to Maccheroni et al., we study the problem of partially hedging a European option H when a hedging strategy is selected through a robust convex loss functional L(·) involving a penalization term γ(·) and a class of absolutely continuous probability measures . We present three results. An optimization problem is defined in a space of stochastic integrals with value function EH(·) . Extending the method of Föllmer and Leukerte, it is shown how to construct an optimal strategy. The optimization problem EH(·) as criterion to select a hedge, is of a “minimax” type. In the second, and main result of this paper, a dual‐representation formula for this value is presented, which is of a “maxmax” type. This leads us to a dual optimization problem. In the third result of this paper, we apply some key arguments in the robust convex‐duality theory developed by Schied to construct optimal solutions to the dual problem, if the loss functional L(·) has an associated convex risk measure ρL(·) which is continuous from below, and if the European option H is essentially bounded.  相似文献   
997.
This article studies how knowledge management (KM) practices improve human capital. We conceptualize KM practices through six dimensions and test the relationship between each dimension and human capital. The empirical study which was carried out in Spanish firms belonging to the biotechnology and telecommunications industries shows that introducing KM practices has a positive impact on the improvement of human capital. In fact, firms that introduce practices related to continuous learning and the development of an innovative culture that encourages R&D projects improve the skills or abilities of their human capital.  相似文献   
998.
This work compares the effects of neoliberal and post-neoliberal land-use policies on forest cover along the Corredor Bioceánico of southeastern Bolivia to determine if rates of agriculturally driven forest clearance have changed since the Morales’ administration came to office in 2005. Satellite image analysis, supported by semi-structured interviews with farmers and representatives of key institutions, shows that deforestation for commercial agriculture in Santa Cruz continues and has increased in certain “hotspots”. Previous research has shown that the environmental effects of neoliberalism on forest cover are varied, but more broadly, reduced state intervention has meant less environmental regulation and greater deforestation, while strong government is better able to curtail deforestation. Although neoliberal policies triggered an unprecedented level of forest clearing in Bolivia, rates have generally continued to increase and can be indirectly linked to the administration's new agrarian reform and pro-environmental regulations. This trend is counterintuitive and stems from unanticipated responses such as deforestation through fire to prove productive use under the reform's socio-economic function requirements. Given increased regulation and enforcement of forest clearing and burning under Morales, in contrast to the neoliberal era, our analyses suggest that rates will continue to increase under the current political climate, which has further polarized the opposition in Santa Cruz.  相似文献   
999.
This study examines the economic impact of sustainable agricultural production systems in Central America. In particular, we investigate the impact of investments promoted by the MARENA Programme in Honduras on the total value of agricultural production (TVAP) of its beneficiaries. Propensity Score Matching techniques along with the Difference‐in‐Differences framework are used to mitigate biases stemming from differences in observed as well as unobserved (time‐invariant) characteristics between beneficiaries and a control group. The econometric estimates suggest that MARENA has had a positive and significant effect on the TVAP of beneficiaries. In addition, the analysis shows that, under alternative scenarios, MARENA yielded higher than expected internal rates of return. The results of this study shed light on the response of small‐scale hillside farmers to economic incentives and lend support to the role of natural resource management projects in Central America as a tool to increase household income while also promoting the conservation of natural resources.  相似文献   
1000.
Abstract

Length-of-stay (LOS) is a key parameter in destination management that determines the number of guest nights relative to arrival numbers, with concomitant repercussions for revenue generation and other performance indicators. This article investigates the development of LOS for 32 destinations in developed and emerging economies as well as Small Islands and Developing States (SIDS). The analysis is based on UNWTO data for 478.5 million international tourist arrivals, or about 40% of the global total in 2015, for the years 1995–2015. Results show considerable differences in LOS between destinations, with a global trend of falling LOS, by 14.8% over the study period. However, in individual destination countries, LOS was found to be increasing. Analyses of LOS trends reveal that these can neither be explained by distance–decay relationships nor business to leisure arrival ratios. Results are discussed with regard for destination management and revenue optimisation, transport infrastructure needs, as well as sector greenhouse gas emissions.  相似文献   
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