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891.
ABSTRACT. This study investigates economies associated with size of New England water utilities. Regression analysis techniques were applied to annual water cost and production data reported in the American Directory of Water Utilities (1968-1969). Modest economies of size in the production of water were found. Because in large communities more water is used per person, total cost increases at a slightly faster rate than population increases, but per unit costs of producing water decline. Substantial economies occurred when the number of customers was held constant and volume of water per customer increased. This study indicates possible economies when two or more of the many very small utilities combine activities to form a larger unit and by encouraging present customers to use more water.  相似文献   
892.
The characteristics of scour holes were discussed including the problems created by them in relation to the hydraulic structures associated with their formation. The philosophy on the design and use of deflector buckets together with the need for plunge basins to dissipate the energy of the high velocity jets were reviewed. Laboratory observations were made to study the erosion of beds of gravel caused by water jets projected from spillway buckets. Flip buckets with 15, 30, 45 and 60 degrees exit angles were utilized. One-quarter inch and %-inch nominal size bed materials were used in the investigation. The gravel was placed in a large comprehensive scour basin to observe their behavior when subjected to the water jets. Besides the formula derived for the maximum depth of scour, a set of dimensionless equations were developed to describe the three-dimensional configuration of scour holes. The dimensions of stable plunge basins could be obtained from these profiles.  相似文献   
893.
This study explores the relationship between electricity consumption, real gross domestic product per capita and carbon dioxide emissions in Zimbabwe. To achieve this, the study set off by examining the stationarity properties of the variables under review with the Zivot-Andrews (1992 Zivot, E., and D.W.K. Andrews. 1992. Further evidence on the great crash, the oil-price shock, and the unit-root hypothesis. Journal Of Business and Economic Statistics 10:251-270. doi: http://dx.doi.org/10.2307/1391541.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) unit root test that accounts for a single structural break. Subsequently, Maki (2012 Maki, Daiki. 2012. “Tests for Cointegration Allowing for an Unknown Number of Breaks.” Economic Modelling 29 (5): 2011–15. https://doi.org/10.1016/J.ECONMOD.2012.04.022 [Google Scholar]) cointegration test, which accounts for multiple structural breaks, is applied for equilibrium relationship between the variables under review while the long run regression of dynamic ordinary least square (DOLS) is employed for long-run coefficients as estimation procedures. In order to account for the direction of causality flow, the Toda-Yamamoto (1995 Toda, H Y.., and Taku Yamamoto. 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal Of Econometrics 66 (1–2):22550. doi: 10.1016/0304-4076(94)01616-8.[Crossref], [Web of Science ®] [Google Scholar]) causality test is used for annual frequency data set spanning from 1971–2014. Empirical evidence from the Maki cointegration test shows that there exists a long-run equilibrium relationship between electricity consumption, carbon dioxide emissions and real gross domestic product per capita over the sampled period. The long-run regression suggests that there exist a positive statistically significant relationship between real income and electricity consumption. Thus, corroborating the electricity-led growth hypothesis. This result is supported by the causality test, as one-way causality is observed running from electricity consumption to real gross domestic product. Thus, this is suggestive to government administrators and policymakers that the Zimbabwean economy is electricity dependent. However, there is a tradeoff for environmental quality. As the increase in electricity consumption increases carbon dioxide emissions. The need for diversification of Zimbabwe energy portfolio to cleaner and environmentally friendly energy sources is recommended, given the world global consciousness for cleaner energy consumption.  相似文献   
894.
Increasingly, the public and governmental agencies are concerned about remediating and reclaiming contaminated sites. Understanding the ecological resources on-site and valuing those resources in terms of future uses is important for determining suitable future land uses. In this article, we suggest the major categories of natural resource information required by managers, policy makers, and the general public for making initial future land-use determinations. We then use a dataset of 25 Department of Energy (DOE) sites slated for remediation to explore whether such data are readily available and whether the data can be used to assess natural resource value. Although information is available for almost all sites on federally endangered and threatened species, this information is less available for state-listed species. Biodiversity information is available only for some sites for birds (N = 17), mammals (N = 15), reptiles (N = 14), amphibians (N = 13), and plants (N = 11) and is almost nonexistent for invertebrates (N = 2). Some information is available for invasive species (N = 9). The number of available habitats is directly related to total acres and nonindustrial acres. Biodiversity of birds, mammals, and reptiles (but not amphibians) is directly related to both total acres and total nonindustrial acres of sites. These data suggest that even over a wide geographical area (from eastern to western United States), biodiversity relates to habitat size and number of habitats available. This information will be useful not only to DOE managers but also to natural resource trustees, ecologists, state and federal regulators, and the general public in the discourse over future uses of these lands.*Published online Author to whom correspondence should be addressed; Joanna Burger  相似文献   
895.
Indicators for sustainable energy development: Brazil's case study   总被引:3,自引:0,他引:3  
This article summarizes the results of the project on indicators for sustainable energy development (ISED) in Brazil. The project's aim was to present energy related economic, social and environmental data to policy makers in a coherent and consistent form, showing interlinkages, time‐series and cross‐sectoral analyses and assess energy policy. Two priority areas assessed by these indicators, regarding the country's energy supply and demand, helped in the identification of a number of energy policy options that focused on specific aspects of the country's energy sector. On the supply side, these options include the development and stimulation of renewable energy, such as small‐scale hydroelectric, wind, solar photovoltaic power and bagasse cogeneration; stimulation of programmes for ethanol use as automotive fuel and sugarcane bagasse cogeneration; and implementation of natural gas‐fired, combined heat and power (CHP) plants. On the demand side, policy options include: the full implementation of the law on efficiency standards for appliances; expansion of utility investment in end‐use energy efficiency; adoption of targets and protocols to reduce energy intensity in the industrial sector; improvement of passenger transport efficiency; and the creation of a fund to improve energy affordability for the poor.  相似文献   
896.
Indicators for sustainable energy development in Mexico   总被引:1,自引:0,他引:1  
This article presents a summary of a study on the application to the Mexican energy sector of a core set of indicators for sustainable energy development (ISED), developed by the International Atomic Energy Agency (IAEA). The study focused on the elaboration of socio‐economic and environmental indicators related to energy production and use, and was aimed at assessing Mexico's existing energy policies and identifying strategies and possible policies that could bring about improvements in major priority areas: energy intensity, atmospheric emissions, energy import dependency and use of renewables. While positive trends have been observed in relation to energy intensity and atmospheric emissions, Mexico is becoming more dependent on imports of gasoline, natural gas and other high‐value secondary energy sources, while exporting significant amounts of primary fuels, such as crude oil. Also, no significant increase has been observed in the use of renewable sources of energy. Social, economic and environmental policies need to be formulated for the energy sector and related investments (public and private) reinforced so that all economic sectors have access to energy from cleaner and more diverse sources.  相似文献   
897.
This article presents an assessment of Russia's energy sector, its current state and planned future direction. The analysis of Russia's energy trends is based on a set of indicators for sustainable energy development (ISED), developed under the leadership of the International Atomic Energy Agency (IAEA). The article discusses Russia's Energy Strategy to 2020, and outlines major developments and challenges of the country's energy system. Russia's energy priorities, captured in the Strategy to 2020, emphasize securing a stable and uninterrupted energy supply; reducing energy intensity and improving energy efficiency; developing the domestic energy resource base; reducing negative environmental impacts; and ensuring affordable energy for the poorer segments of the population. Energy needs and challenges are discussed in relation to the three aspects of sustainability as defined in Agenda 21: economic, social and environmental. Concerns are expressed regarding environmental repercussions of energy development, in particular since Russia's 1998 economic rebound. There are also concerns, despite the economic recovery, that anticipated increases in energy tariffs may exceed the affordability of poorer segments of the population.  相似文献   
898.
我国石油消费现状及其战略思考   总被引:1,自引:0,他引:1  
石油是支撑经济发展和国防现代化的基本能源之一。在当今国际社会中 ,石油已成为世界政治、经济、军事和外交斗争的特殊武器 ,成为一国经济发展、社会稳定以及国家安全的重要保障条件。我国目前石油供需形势严峻 ,主要表现为 :石油储量接替准备不足 ,老油田稳产面临严峻形势 ;需求增长过快 ;对外依存度较高 ;运输和贮存能力较小等方面。石油的安全及其保障问题关系到我国的经济安全和国家安全 ,因此 ,有必要研究我国的石油消费现状及发展战略。笔者针对我国的石油消费现状 ,分析了目前我国石油战略中存在的问题 ,探讨了我国的石油战略。  相似文献   
899.
提高垃圾焚烧电厂热能利用效率的几个途径   总被引:2,自引:0,他引:2  
采用能量分析的方法,从几个侧面对垃圾焚烧发电厂热能利用效率低下的原因进行分析,提出了解决垃圾焚烧发电厂热能利用效率的途径:选择合适的炉型,降低散热损失以提高锅炉效率;对进厂垃圾进行堆酵以沥出其中水分,提高入炉垃圾低位热值;提高锅炉出口蒸汽参数,采用回热循环等措施增加蒸汽的可用能,提高系统发电效率。  相似文献   
900.
论我国能源利用方式及大气污染防治   总被引:2,自引:0,他引:2  
通过对我国能源结构和利用方式的论述,以及能源燃烧产生的主要大气污染物对环境影响定性和定量的分析,提出了相应的污染防治对策。  相似文献   
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