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971.
While the magnitude of potential consequences might vary, most hazards encountered in pilot plant operations are the same as those experienced in full scale commercial facilities. For example, safeguarding hazardous chemicals storage and transfer, protecting reaction vessels against catastrophic failure or runaways, all require careful consideration regardless of scale. We, however, want to address some aspects of pilot plants which can introduce hazards unique or more common to their operation. To illustrate, we present some case histories from our own pilot plant experience in BASF's Chemical Engineering Department, and include a brief discussion of some corresponding safeguards to mitigate these situations.  相似文献   
972.
973.
We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   
974.
975.
In this paper the impact of price risk on millet production in Niger is investigated. The hypothesis that farmers respond to output price risk is tested. The results indicate that millet acreage planted decreased when millet price risk increased or when price risk of the competing crop decreased and therefore farmers do respond to changes in risk.  相似文献   
976.
Ranking Crop Yield Models: A Comment   总被引:1,自引:0,他引:1  
This comment discusses key specification issues that may have affected the performance and, therefore, the ranking of parametric models that were compared in a recent AJAE article. A procedure to obtain the most flexible parametric model specification possible, given the particular probability distribution function on which the model is based is presented. These specifications also allow for standardized and, therefore, more valid comparisons across parametric models that are based on different probability distributions. Finally, the comment cautions against generalization of the rankings in that AJAE article and recommends that these more flexible specifications be adopted in future comparisons and applications.  相似文献   
977.
I present a consumption-based dynamic asset pricing model in which international market correlations vary counter-cyclically over time. The driving force in the model is the time-varying effective risk aversion induced by external habit formation. Market returns are driven by fundamental outputs and discount rates. When risk aversion is high, the effect of discount rates on market returns rises with the market price of risk. To the extent that countries share risk, the cross-country correlation of discount rates exceeds the cross-country correlation of fundamental outputs. In bad times, market correlations rise as returns are mostly driven by discount rates. Thus, consistent with the empirical evidence, periods of high risk aversion are associated with high market correlations and high market volatility. After calibration, my model is consistent with the observed variation in market correlations, as well as other features of asset prices including the equity premium and market volatility.  相似文献   
978.
 This paper explains how and why the developed countries are undergoing a fundamental shift away from a managed economy and towards an entrepreneurial economy. This shift is shaping the development of western capitalism and has triggered a shift in government policies away from constraining the freedom of business to contract through regulation, public ownership and antitrust towards a new set of enabling policies which foster the creation and commercialization of new knowledge. The empirical evidence from a cross-section of countries over time suggests that those countries that have experienced a greater shift from the managed to the entrepreneurial economy have had lower levels of unemployment.  相似文献   
979.
Growth in legal gaming in the United States over the past quarter century or so is well-documented. One important factor fueling this growth was the passage of the Indian Gaming Regulatory Act of 1988, which permitted Native American tribes to establish, under agreements or “compacts” with the states in which they are located, casinos offering what is known as Class III gaming: slot machines, blackjack, roulette, and other games. Since the passage of the Act, there have been 21 Native American casinos established in Michigan. Also, three non-Native American casinos opened in Detroit in 1999 and 2000. This growth in the number of casinos has sparked a wide-ranging debate over the social and economic impacts of casino development.The purpose of this research is to focus on the crime issue in the broader casino debate. We investigate the impact of these Michigan casinos on the rates of burglary, robbery, larceny and motor vehicle theft (property crimes) in casino host counties as well as in nearby counties. We employ a panel data set with annual observations on all 83 Michigan counties for the period 1994–2010. The dataset includes crime rates taken from the FBI crime data series, variables for the presence of a casino in a county or in a nearby county, the scale of a casino's operations as measured by revenues, and a variety of control variables suggested by the broader literature investigating the factors that determine crime rates generally.Our results suggest that in most cases the property crime rates studied are not affected by the presence or size of a casino in a county or in a nearby county. The largest such impact, which is negative, is for motor vehicle theft. The size of a casino does have a small positive effect on the motor vehicle theft rate.  相似文献   
980.
Governments around the world are beginning to embrace a new form of environmental regulation – mandatory disclosure of information. While information disclosure programs appear to have an impact on subsequent firm behavior – often resulting in lower levels of pollution – little is known about the costs and benefits of these programs and whether or not they enhance social welfare. This paper presents a simple bargaining model where mandatory information disclosure is used to overcome a lack of information on the part of the public. We characterize the conditions under which information disclosure will lead to a reduction in emissions, and ultimately, the conditions under which it will enhance social welfare. Several extensions of the model are briefly explored, including the effect of two sources of pollution – only one of which is subject to information disclosure. This paper was prepared while V. Santhakumar was a Visiting Scholar at the Vanderbilt Center for Environmental Management Studies, Vanderbilt University.  相似文献   
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