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131.
We investigate how emission abatement and technological innovation provide different solutions to reduce pollutant emissions. In the case of a stock externality emission abatement leads to a smooth and continuous adjustment of emissions. Conversely, technological innovation has to be interpreted as an option on a less polluted environment and can justify the use of a pollution threshold above which it is optimal to start a research and development programme for a less polluting technology. It is shown that technological innovation interferes with the traditional emission abatement approach. The optimal abatement level is logically lowered once the less polluting technology is available; nevertheless a temporary increase in emissions is optimal during the research and development period. The usual Pigouvian tax system proves to remain an efficient corrective instrument. A numerical application to the Greenhouse effect is provided.  相似文献   
132.
Profitability of cow-calf production is determined largely by market prices, calf weaning weights, and cow productive life. While producers individually have no effect on prices, weaning weights and productive life have genetic influences and hence can be altered by selection programs implemented by producers. We investigate the impact of a mutation in the leptin gene (exon 2; single nucleotide polymorphism [SNP] 305) on cow-calf profitability. Prior research shows that this mutation has effects on performance and traits of fed cattle and milk production in dairy cows. Using data from a teaching-research herd, we find that it is also associated with calf weaning weights and cow productive life. A bio-economic stochastic simulation demonstrates that the mutation has statistically positive impacts on profits, suggesting that producers can profitably make use of this information.  相似文献   
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The international ski tourism industry is highly vulnerable to inter-annual climate variability and climate change. Accordingly, there is a strong need to advance our understanding of climate risk for this multi-billion tourism market that is so important to mountain regions around the world. This study addressed major limitations in the ski tourism literature, while concurrently supporting priority information needs of ski tourism stakeholders. An improved version of SkiSim 2.0 is applied to all 34 alpine ski areas in southern Ontario (Canada) to examine potential changes in the capacity of this regional marketplace. Model improvements include differential snowmaking capacities of individual ski areas, updated snowmaking decision rules, as well as a new indicator, termed ‘terrain-days’, to estimate changes in system capacity. The results project two fundamentally different futures for this ski tourism marketplace under climate change. If the international community succeeds in achieving the?+?2°C Paris Agreement policy goal, then losses in system capacity can be limited to less than 10% in the mid- and late-century. In contrast, a high-end emission scenario (RCP 8.5) would severely disrupt this ski tourism market by mid-century, with system capacity losses between 28% and 73%.  相似文献   
137.
This paper deals with the support of strategically oriented financial planning processes in business firms. In handling a financial planning problem, the decision maker has to deal with a number of complications. In this paper special attention is paid to the risk with regard to the outcomes of the financial plan and the existence of multiple, conflicting goals. An interactive approach to financial planning is presented. Risk is modeled by means of so-called multi-factor risk models and multiple goals are explicitly accounted for through the use of an interactive goal programming method. The use of the interactive approach will be numerically demonstrated by means of an exemplary planning problem.  相似文献   
138.
The diversifying power of inflation-linked (IL) bonds relative to traditional asset classes has changed significantly. In this paper, we study the dynamics of conditional volatilities and correlations for three asset classes, IL bonds, nominal bonds and equities, in the USA and Europe. Using a DCC-MVGARCH for the period 1997–2007, we highlight the change that took place in 2003. Although IL bonds once had definite diversification power, they are now highly correlated with nominal bonds and have reached similar volatility levels. As a result, the two asset classes are practically substitutable. This seems to be due to more stable inflation expectations and to a more liquid IL bond market. Although diversification was a valuable reason for introducing IL bonds in a global portfolio before 2003, this is no longer the case. Dynamic portfolio optimisation using our estimates of conditional correlations and volatilities clearly demonstrates that the optimal weight of IL bonds in a portfolio decreased sharply in 2003 in favour of nominal bonds and equities.  相似文献   
139.
This article deals with goal programming as an aid to resolving transportation problems. The objective of this study is to demonstrate the use of goal programming as an approach to reducing total cost in transportation problems that possess variable supply and demand requirements. A generalized goal programming model is formulated and applied to a series of transportation problem situations based on the empirical data provided by a medium-size trucking firm. Comparison of the results demonstrates the cost advantage of using the goal programming model in place of the transportation method and integer interval linear programming.  相似文献   
140.
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