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51.
日本核电力资源开发的特点及问题   总被引:2,自引:1,他引:1  
电力资源供应是否充沛已成为目前制约世界经济稳定增长的主要因素,由于核发电优势明显,利用核动力开发电力资源业已成为一些国家保障经济发展的重要选择。日本是利用核能开发电力资源的大国,长期以来在"国策民营"体制下建立起来的核发电业有效地保障了经济的发展。但另一方面,日本在核发电业的发展过程中也表现出一些问题,这些问题对于意欲大规模发展核能的国家来说不仅具有参考价值,而且在国际合作开发与利用核电非常盛行的今天也具有十分重要的现实意义。  相似文献   
52.
Fuel cell technology is becoming a significant option as an energy technology. Attracting significant research funding, industry research and development (R&D), and commercial anticipation different fuel cell technologies are indicating potential as viable products. One of the anticipated applications of the technology is portable fuel cells. Ranging from small back-up power systems to small micro watt solutions portable fuel cells have been widely demonstrated but lacking widespread commercial exploitation. This paper presents the prospects of portable fuel cells which resulted from a Delphi study.  相似文献   
53.
Long term increases of petrol prices and the threat of a global climate change have created in the automotive industry a new competitive environment based on the development of more sustainable technologies. Using the real option reasoning lens we provide a theoretical framework to better account for the technological and market uncertainties and irreversibilities that impact the investment and innovation decisions of automotive firms supporting the development of more sustainable vehicle technologies. We investigate the case of hybrid vehicles in a transitional perspective by insisting on their potential to influence the dynamic shaping of investment decisions of firms in the car industry. We consider the hybridization strategy as intra-project and inter-project compound growth options to manage the flexibilities and irreversibilities of investment decisions during the transition process. We provide four different-sometimes conflicting-strategic rationales structuring the investment efforts of firms in hybrid vehicles and illustrate them with numerous examples from the automotive industry.  相似文献   
54.
我国商品天然气计量采用的体积计量方式不能反映作为燃气的主要质量指标——热值,以及天然气与人.燃气的热值差别.建议国内商品天然气的计量采用国际上通用的热值计量方式,以使贸易交接更加科学、合理.  相似文献   
55.
美国的燃油税政策及借鉴   总被引:3,自引:0,他引:3  
刘斌 《涉外税务》2007,(8):50-53
本文介绍了美国燃油税的产生、现状和发展趋势。借鉴其政策的经验和教训,对中国制定和实施燃油税政策提出了一些建议:尽早开征、设置合理的税率、税收款专款专用、加强公交基础设施建设以及完善公路税费政策等。  相似文献   
56.
The main forest transitions that took place in south-central Chile from the end of the last glaciation to the present are reviewed here with the aim of identifying the main climatic and socio-economic drivers of land cover change. The first great transition, driven primarily by global warming, is the postglacial expansion of forests, with human populations from about 15,000 cal. yr. BP, restricted to coastlines and river basins and localized impact of forest fire. Charcoal evidence of fire increased in south-central Chile and in global records from about 12,000 to 6000 cal. yr. BP, which could be attributed at least partly to people. The subsequent expansion of agriculture led to much clearing of forests and the spread of weeds and other indicators of open habitats. The Spanish colonial period in America may have been followed by a transient expansion of forest cover into abandoned land, as indigenous population declined rapidly due to disease and slaughter. The 18th and 19th centuries brought about extensive loss of forests due to the massive impact of lumber extraction for mining operations both in central Chile and in western North America. Two centuries of intensive deforestation, coupled to grazing by cattle and extremely variable rainfall had long-lasting effects on forest cover in south-central Chile, which persist until today. The transition from a preindustrial to an industrial society brought about the “golden age” of timber harvest, assisted by mobile sawmills and railway transportation since the late 1800s. These advances led to the exhaustion of native commercial timber by the late 20th century in south-central Chile. In North America, harvestable stands were exhausted in New England and the Midwest around 1920. Settlement of the independent territories in the late 1800s and early 1900s implied vast burning and clearing of land and mounting soil erosion. Industrial forestry, based on government-subsidized massive plantations of short-rotation exotic trees, developed in the late 20th century, in connection with postindustrial displacement of exploitative activities from developed to third-world nations. In the last two decades, economic globalization and free trade promoted the expansion of new crops and further decline of woodlands, despite modest increases in forest cover. These patterns are repeated in many Latin American countries. To prevent further depletion of native forest resources and to provide an insurance against climate change, in the 21st century developing nations should aim at: (1) relocating subsidies from fiber farms to restoring diverse forest cover, (2) promoting ecosystem management of diverse forest and crops within landscapes, and (3) fostering diverse cultural relationships between people and their land.  相似文献   
57.
This paper defines the notion of key inventors — those whose patenting is simultaneously highly productive and also widely cited. By implication, key inventors should be the leaders in any developing new field and we investigate the validity of the notion through an exploration of two emerging technological fields: fuel cell and nanotechnology. The nature of the two groups is compared to discuss the differences between the technological groups.  相似文献   
58.
The key objective of this study is to investigate the interrelationship between fuel economy gaps and to quantify the differential effects of several factors on fuel economy gaps of vehicles operated by the same garage. By using a unique fuel economy database (fueleconomy.gov), users’ self-reported fuel economy estimates and government’s fuel economy ratings are analyzed for more than 7000 garages across the United States. The empirical analysis, nonetheless, is complicated owing to the presence of important methodological concerns including potential interrelationship between vehicles within the same garage and unobserved heterogeneity. To address these concerns, bivariate seemingly unrelated fixed and random parameter models are presented. With government’s test cycle ratings tending to over-estimate the actual on-road fuel economy, a significant variation is observed in the fuel economy gaps for the two vehicles across garages. A wide variety of factors such as driving style, fuel economy calculation method, and several vehicle-specific characteristics are considered. Drivers who drive for maximum gas mileage or drives with the traffic flow have greater on-road fuel economy relative to the government’s ratings. Contrarily, volatile drivers have smaller on-road fuel economy relative to the official ratings. Compared to the previous findings, our analysis suggests that the relationship between fuel type and fuel economy gaps is complex and not unidirectional. Regarding several vehicle and manufacturer related variables, the effects do not just significantly vary in magnitude but also in the direction, underscoring the importance of accounting for within-garage correlation and unobserved heterogeneity for making reliable inferences.  相似文献   
59.
This paper empirically examines the effect of the U.S. Corporate Average Fuel Economy (CAFE) standards on the technological progress in automobile fuel efficiency. Using detailed vehicle attributes data from 1978 through 2018, we find that more stringent fuel economy standards increase the rate of technological improvements in new passenger cars, and this effect is primarily driven by the response of U.S. automakers. We do not find evidence that CAFE standards have a similar effect on the technical change in light-duty trucks. Our results also indicate that higher gasoline prices have a significant and positive effect on the improvement of fuel-saving technology in both passenger cars and light trucks. Using our empirical estimates, we project that the recent rollback of Obama-era CAFE standards would forego an approximately 2-percent increase in cars’ fuel economy over the 2021–2025 period as a result of technological progress.  相似文献   
60.
Global ethanol production has grown rapidly due to national renewable fuel programs. Concern has grown over impacts that land conversion and crop displacement driven by ethanol feedstock production might have on water resources. In this paper, we examine irrigation decisions of agricultural producers in the Kansas portion of the High Plains Aquifer in response to local ethanol market expansion. To identify the effects of ethanol expansion on irrigation decisions, we examine field-level data on irrigation water use, irrigated acreage, and crop decisions for the years 2003–2017 for nearly 23,000 fields in Kansas. We measure the response of three irrigation decisions, (i) irrigated acreage, (ii) irrigation per acre, and (iii) total water use to the introduction and capacity expansion of an ethanol plant. We find that ethanol market expansion did lead to increases in irrigation water use. Specifically, a 10 % increase in ethanol capacity within 50KM increases annual water use by 0.22 % per field (4.8 acre-inches/field). We predict that ethanol markets accounted for about 4% of total irrigated water use in 2017.  相似文献   
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