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41.
International commercial flights (with the exception of flights between countries in European Union including Iceland, Norway and Liechtenstein) are currently not subject to greenhouse gas emission reduction regulation. To formulate effective and efficiency policy to manage greenhouse gas emissions from air transport, policy makers need to determine the emissions profiles of all airlines currently flying into their country or region. In this paper, we use 2012 data on airlines' aircraft characteristics, passenger load and cargo load (obtained from statistics reported by Australian Government Bureau of Infrastructure, Transport and Regional Economics) to estimate the volume and carbon efficiency on each international route flying to and from Australia. This is the first study to use actual passenger and cargo load data to determine the greenhouse gas (specifically CO2) efficiency of airlines operating in the Australian international aviation market. Airlines' CO2 emission profile is dependent on many factors including but not limited to the aircraft used, payload, route taken, weather conditions. Our results reveal that the airlines’ CO2 emission profile is not only dependent on the aircraft used and the number of passengers but also the amount of cargo on each flight.  相似文献   
42.
天然气输送管线安全运行面临风险,本文主要对天然气输送管线生产管理进行探讨。  相似文献   
43.
In a bid to reduce greenhouse gas emissions, several countries worldwide are implementing policies to promote electric vehicles (EVs). However, contrary to expectations, the diffusion speed of EVs has been rather slow in South Korea. This study analyzes consumer preferences for the technological and environmental attributes of EVs and derives policy and environmental implications to promote market diffusion of EVs in South Korea. We conduct a choice‐based conjoint survey of 1,008 consumers in South Korea and estimate the consumer utility function using a mixed logit model considering consumer heterogeneity. Based on the consumer utility function, we analyze consumers' willingness‐to‐pay (WTP) for EV attributes such as driving range, charging method, charging time, autonomous driving function, carbon dioxide (CO2) reduction rate, and purchase price. The results indicate that the current low acceptance of EVs is due to their relatively high price and lack of a battery charging technology that satisfies consumers' expectations of the charging method and time. One interesting finding is that Korean consumers have a relatively higher WTP for the CO2 reduction rate of EVs than consumers in other countries; however, they do not consider CO2 reduction over other technological attributes when choosing EVs. This implies that the rate of CO2 reduction of EVs is not an important factor for South Korean consumers when buying EVs. We also calculate the effect of CO2 reduction with the market penetration of EVs and find that CO2 reduction through the diffusion of EVs depends on the country's electricity generation mix.  相似文献   
44.
Major climate-cum-energy policies and respective impact projections rest on the widespread belief that increased energy efficiency can be equated with savings in energy use and emissions. This belief is flawed. Due to the rebound effect emissions savings from energy efficiency improvements will be generally less than what is technically feasible, or even be reversed. By means of an analytical general equilibrium model we demonstrate the latter to be true in a case that is both stark and relevant: if electricity generation is subject to a cap-and-trade scheme with partial coverage, increased efficiency of electric devices leads unambiguously to increased carbon emissions. The result implies that a proper distinction between the energy rebound and the carbon rebound is warranted, and that public policy must carefully consider the interactions between energy efficiency promotion and carbon pricing.  相似文献   
45.
本文研究了水轮发电机定子穿心螺杆由于自身的涡流损耗而造成的温升情况,并分析了3种穿心螺杆的绝缘结构,得出了最佳的绝缘结构方案。  相似文献   
46.
We focus on identification and estimation of potentially negative environmental impacts of unconventional natural gas extraction on property values in the United States and advance previous research by contributing new data and new identification strategies for isolating these potential impacts. Our study area consists of two counties in Pennsylvania that are home to large amounts of unconventional natural gas extraction but are otherwise isolated from other resource extraction industries or large urban areas. We deploy parametric, semi-parametric, and matching hedonic regression models that include recent quasi-experimental methods and, in contrast to previous research and much popular intuition, we fail to find robust significance that negative environmental externalities of natural gas extraction are manifested in nearby property values. While there may be plausible risks associated with unconventional natural gas extraction, we do not find consistent evidence to suggest that these risks significantly affect nearby property values.  相似文献   
47.
Recent legislation intended to increase the use of renewable energy sources and lower the amount of carbon dioxide emissions from energy has changed the structure of energy markets. The effect of these policies on carbon-intensive fuel sources is rather obvious. For natural gas, though, the effect is not immediately clear. This letter uses a structural model of natural gas demand to uncover whether these policies have led to increased demand because natural gas is a relatively clean source of energy that couples well with renewables or if these policies have crowded out natural gas on net.  相似文献   
48.
We study the behavior of U.S. natural gas futures and spot prices on and around the weekly announcements by the U.S. Energy Information Administration of the amount of natural gas in storage. We identify an inverse empirical relation between changes in futures prices and surprises in the change in natural gas in storage and that this relation is not driven by the absolute size of the surprise. The evidence also indicates prices react first in the futures market for natural gas with that information then flowing to the spot market. Post 2005, corresponding to a period of significant increases in the production of natural gas in the United States, the response of prices to storage surprises was larger in absolute value. No evidence is found of economically meaningful reactions to the surprise other than on the date the storage news is released. The results demonstrate the importance of fundamental information in the formation of natural gas prices.  相似文献   
49.
本文首先分析了燃气管道可能遭受雷击的主要通道,然后提出了堵塞这些主要危害通道的基本思路和基本技术要求,并对燃气管道防雷设计的基本原则和方法作了详尽的论述,为燃气管道的防雷设计提供了实践依据。  相似文献   
50.
近年来,中国天然气行业市场化改革不断深化,市场原有竞争格局受到挑战,但供应商现有客户评价管理较为粗放,客户评价体系不尽完善。新形势下的天然气行业客户评价及精准营销体系亟待建立,新体系遵循的原则包括:多维衡量,因地制宜;分类细化,量化评价;结合场景,灵活运用。可依据"销量、价格、效益、信用、协作"5个维度及15个指标,选取所需指标并赋予权重,获取指标数据源,运用分数归类定级方法进行判断。客户评价是工具,精准营销是措施。建议从做好精准营销基础项目、立足本职工作替客户分忧、运用大数据探索精准营销3个层面进行规划与升级。  相似文献   
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