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41.
范衡 《价值工程》2014,(24):30-31
随着我国煤矿开采深度的不断加大,煤层的透气性逐渐降低,而瓦斯的压力、浓度、放散量和速度则不断升高,因此加大瓦斯治理力度尤为关键。本文我们将针对当前我国煤矿瓦斯治理的现状,针对当前工作中存在的问题,提出煤矿瓦斯治理工作方面的意见和措施,以期能够提高煤矿的安全性,减少煤矿瓦斯事故的发生。  相似文献   
42.
周新 《价值工程》2014,(5):68-69
本文通过对管道光纤预警工作原理、管道光纤预警系统组成等进行阐述,进而在一定程度上为天然气管道在线预警与定位提供参考依据。  相似文献   
43.
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   
44.
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   
45.
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   
46.
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   
47.
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   
48.
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   
49.
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   
50.
李磊 《价值工程》2014,(24):74-75
本文主要探讨丘陵地区市政排水管道的设计思路,着重分析了丘陵地区排水系统的特点及相应的工程设计方案,确保丘陵地区市政排水管道建设具有可行性。  相似文献   
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