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1.
Benefits analysis of US Federal government research, development, demonstration, and deployment (RD3) programmes for renewable energy (RE) technology improvement typically employs a deterministic forecast of the cost and performance of renewable and non-renewable fuels. The benefits estimate for the programme derives from the difference between two forecasts, with and without the RD3 programme in place. Three deficiencies of this approach are that it ignores: (1) uncertainty in the cost of non-renewable energy (NRE); (2) the possibility of adjustment to the RD3 effort commensurate with the evolving state of the world; and (3) the underlying technical risk associated with RD3. In this paper, an intuitive approach to determining the option value of RE RD3 is developed. This approach seeks to tackle the first two deficiencies noted above by providing an estimate via a compound real option of an RE RD3 programme in a future with uncertain NRE costs. A binomial lattice reveals the economic intuition underlying the decision-making process, while a numerical example illustrates the option components embedded in a simplified representation of current US Federal RE RD3.  相似文献   
2.
Suitability of the negative binomial distribution for use in estimating the probabilities associated with sampling lots of shelled peanuts for aflatoxin analysis has been studied. Large samples, called “minilots,” were drawn from 29 lots of shelled peanuts contaminated with aflatoxin. These minilots were subdivided into ca. 12 lb samples which were analyzed for aflatoxin. The mean and variance of these aflatoxin determinations for each minilot were determined. The shape parameterk and the mean aflatoxin concentrationm were estimated for each minilot. A regression analysis indicated the functional relationship betweenk andm to be:k=(2.0866+2.3898m) × 10−6. The observed distribution of sample concentrations from each of the 29 minilots was compared to the negative binomial distribution by means of the Kolmogorov-Smirnov test. The null hypothesis that each of the true unknown distribution functions was negative binomial was not rejected at the 5% significance level for all 29 comparisons. Journal Series Paper of the North Carolina State University Agricultural Experiment Station, Raleigh, N.C.  相似文献   
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Concerns about global climate change have substantially increased the likelihood that future policy will seek to minimize carbon dioxide emissions. As such, even today, electric utilities are making resource planning and investment decisions that consider the possible implications of these future carbon regulations. In this article, we examine the manner in which utilities assess the financial risks associated with future carbon regulations within their long-term resource plans. We base our analysis on a review of the most recent resource plans filed by 15 electric utilities in the Western United States. Virtually all of these utilities made some effort to quantitatively evaluate the potential cost of future carbon regulations when analyzing alternate supply- and demand-side resource options for meeting customer load. Even without federal climate regulation in the US, the prospect of that regulation is already having an impact on utility decision-making and resource choices. That said, the methods and assumptions used by utilities to analyze carbon regulatory risk, and the impact of that analysis on their choice of a particular resource strategy, vary considerably, revealing a number of opportunities for analytic improvement. Though our review focuses on a subset of US electric utilities, this work holds implications for all electric utilities and energy policymakers who are seeking to minimize the compliance costs associated with future carbon regulations.  相似文献   
5.
Eighteen sessions of cognitive–behavioral (CB) and 13 sessions of psychodynamic–interpersonal therapy obtained from experienced clinicians in a naturalistic setting were investigated to determine the various therapeutic interventions associated with high and low emotional experiencing (EXP). Clients receiving reflections and acknowledgments, affiliative and noncontrolling interventions, or interventions highlighting nonspecific client content were associated with maintained high EXP. Lengthier interventions and interventions rated as affiliative but moderately controlling were associated with shifts to low EXP. For clients of CB therapists, questions, interventions rated affiliative but controlling, and highlighting minimal emotional content were also associated with shifts to low EXP. Male therapists were associated with clients who maintained high EXP and female therapists were associated with clients who shifted to low EXP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
High-volatile bituminous and lignite coals have been studied by means of carbon-13 n.m.r. employing cross-polarization and magic-angle-spinning techniques. The solids spectra have been compared to those of the coal-derived liquids. By artificially broadening the high-resolution spectra of the liquids, a striking similarity in line shape and position is observed when the liquid spectra are compared with those of the corresponding solid coal. It is noted however that certain bands visible in the solid are no longer present in the liquefied state. The significance of these results is discussed in terms of carbon skeletal structures present in the solids but not in the liquids.  相似文献   
7.
A computer model that accounts for sampling, subsampling, and analytical variability was developed to simulate aflatoxin testing programs. Monte Carlo solution techniques were employed to account for conditional probabilities that arise from multiple samples, subsamples, and/or analyses being used in testing programs. The aflatoxin testing program to be used on the 1974 peanut crop was evaluated by use of the described model. ARS, USDA, and Biological and Agricultural Engineering Department, North Carolina State University, Raleigh, NC 27607.  相似文献   
8.
A Fortran IV computer program was developed to calculate the composition at equilibrium of products from a single-stage coal gasification process involving coal, H2 and steam. This program was used to develop equilibrium concentration profiles for various components and heating values of dry product gas as a function of temperature, pressure and percentage steam in a hydrogen-steam mixture feed gas. Based on the results, a useful range for the variables, from the thermodynamic point of view, has been established.  相似文献   
9.
The rate data of the hydrocracking reaction of low-temperature tar are presented. The overall order of the reaction was found to be second order below 1500 psi and first at and above 1500 psi. The rate of gasoline formation from tar was found to be represented by k1g = 0.14 k1N.O + 0.16 k1S + 0.14 k1O + 0.12 k1N + 0.08 where k1N.Ok1Sk1O and k1N are first order rate constants for the hydrocracking of hydrocarbons, and sulphur, oxygen and nitrogen compounds present in tar respectively.  相似文献   
10.
Oil product from the hydrogenolysis of a high-volatile bituminous coal was separated by solubility, fractionated by gel permeation chromotography and characterized by structural analysis. The average structural unit in the hexane-soluble, aromatic oil fraction consists of 1–3 aromatic rings with 0.3-0.5 of the ring carbons substituted by alkyl groups and oxygen containing groups. Molecular weights vary from 200 to 500. The larger molecular weight fractions have longer alkyl chains and lower carbon aromaticities. The molecules are mainly of single unit structures. The average structural units in asphaltene fractions contain from 2.5-4 aromatic rings, are of higher carbon aromaticities and contain shorter alkyl groups. The asphaltene molecules consist of two or more structural units, crosslinked together, and have molecular weights of 300–1400. The oxygen content of the fractions decreases with decreasing molecular weight. Increasing the amount of ZnCl2 catalyst during hydrogenolysis resylts in an increased yield of lower-molecular-weight material, but no change in the structural properties of the product. This is interpreted to mean that ZnCl2 is active in the scission of covalent bonds between structural units during liquefaction and that the hydrogenolysis reaction is mostly cleavage of crosslinks between structural units with minimal reaction of the units themselves.  相似文献   
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