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1.
The message of this research is that in the standard calibrated setting of Computational General Equilibrium (CGE) models, the welfare measures typically used to compare benchmark with counterfactuals are numéraire dependent. This evaluation bias affects the compensating variation and the Konüs index of cost of living. We show that the equivalent variation is neutral regarding the choice of value units in calibrated models but would be affected as well in uncalibrated CGE models. We illustrate with a simple example and propose an even simpler theoretical solution to overcome these biases; all that is required to have correct welfare estimates is to compensate normalizing with a suitable price index. This type of correction is necessary to overcome the sometimes blind implementation of welfare measures in numerical general equilibrium analysis. We show that the induced quantitative errors may be substantial providing biased welfare estimates and misleading results.  相似文献   
2.
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.  相似文献   
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Household Consumption and Expenditures Surveys (HCES) are increasingly being used to make inferences about individual food consumption, despite the fact that they collect food data at only the household level. Usually the analysis assumes that the household’s food is distributed among its members in direct proportion to each member’s share of the household’s total energy requirements; what is referred to as the adult male equivalent (AME) approach. Using the 2011–2012 Bangladesh Integrated Household Survey—which collected consumption data for all members of rural households using combined 24-hour recall (24HR) and food weighing methods—this study directly compared probability-based average estimates of intakes, intake gaps, and the prevalence of inadequacies as estimated by the 24HR and those calculated using the AME approach for energy and each of four micronutrients: vitamin A, iron, zinc, and calcium.At the population level, for iron, vitamin A, and calcium, more than 97% of all individuals had the same estimated prevalence of adequate or inadequate nutrient intakes using 24HR and AME-based estimates. In the case of energy and zinc, roughly 77 and 83% of the sample population had identical adequacy statuses, respectively. The magnitude of inadequacies (the nutrient gaps) differed by 8 percentage points for energy and less than 3 percentage points for the four micronutrients. Disaggregating intakes and inadequacies by age groups revealed that the vast majority of variance between the two methods was highly concentrated in the first few years of life. Children 3 years of age and younger constituted 7.5% of the population but had 13.1% of the inconsistencies in intake adequacy status. 54% of children 3 and under had at least one pair of inconsistent prevalence estimates. While there are important differences in the levels of estimated energy and micronutrient intakes using 24HR and the AME-based estimates for children 3 and under, the results are remarkably comparable for the rest of the population.  相似文献   
5.
基于数值仿真计算和微波网络理论,提出了一种多层介质中频率选择表面(FSS)等效电路的分析方法。该方法物理过程直观,计算量小,适用于二维任意形状FSS等效电路的精确求解。以方形贴片型FSS为例验证了等效电路模型的准确性,并分析了多层介质对其等效电路参数的影响规律。最后,基于滤波器理论与FSS等效电路模型设计了双层带通型FSS,计算结果表明全波仿真结果与理论计算结果基本一致,为多层FSS的综合设计提供了一种精确设计方法。  相似文献   
6.
This paper proposes four criteria for the selection of a better measure of living standards: it should be comprehensive, correlation sensitive, preference based, and fairness based. These criteria are applied to the following measures: income, equivalent income, capabilities, and satisfaction. The paper then explores the relationship between the space of goods and services, the space of budgets, and the more fundamental space of the aspects of life that people really care about. The importance of the fairness principles guiding interpersonal comparisons is highlighted.  相似文献   
7.
研究土地利用率的核心意义,原于其能够缓解土地资源禀赋稀缺的现状;发展厚朴林和杜仲林间作玉米与大豆系统可以提高土地利用率,促进林农集约经营,有效保护生物多样性,促进中药材产业发展,增加农民的经济收益,推动社会主义新农村建设。  相似文献   
8.
在税收实务中,视同销售是一个重要内容。视同销售涉及税种广泛,内容丰富,增加了纳税风险。本文试从视同销售的相关规定出发,比较分析视同销售在各个税种税法规定的异同,以便较为清晰的认识视同销售行为,减少纳税人的纳税风险。  相似文献   
9.
陈斗 《价值工程》2010,29(7):255-256
为了培养学生的认知能力、应用能力和创新能力,从教学目标、学情、教学方法、教学组织、教学效果等5个方面对《等效电源定理》这一课的教学设计进行说明。  相似文献   
10.
We consider the incomplete assets market and assume that the market has no-arbitrage. Then there are many equivalent martingale measures associated with the market. Among them, a probability measure which minimizes the relative entropy with respect to the original probability measure P, has a special importance. Such a measure is called the minimal entropy martingale measure (MEMM). In a previous paper, we have proved the existence theorem of the MEMM for the price processes given in the form of the diffusion type stochastic differential equation. In this article we discuss the MEMM of the jump type price processes, or especially of the log Lévy processes, and we give the explicit form of MEMM.  相似文献   
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