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101.
The standard textbook analysis shows that drivers as a group lose from congestion charges. However, it omits taste heterogeneity, shorter travel times far out in the larger network arising from less blocking back of upstream links and the possibility for drivers to reschedule. Taking account of these factors, using a dynamic scheduling model with heterogeneous users we find that all three add significantly to the benefit of the Stockholm congestion charges and that drivers as a group benefit from these charges even without recycling of revenues. This paper also provides an update on the consumer benefits of the Stockholm charges.  相似文献   
102.
The Sustainable Energy Authority of Ireland (SEAI) administers the Better Energy Homes scheme to provide a financial incentive for home owners to engage in energy efficiency retrofits. This study analyses data from the scheme and Building Energy Rating data for participants to the scheme to examine the value for money achieved by households. In addition, this research identifies which retrofit combinations provide greatest value for money, in terms of energy efficiency gains, for the grant provider. We utilize an error-in-variables approach to model the variation in benefits accruing to households of varying characteristics. We find that household and grant provider surplus can be maximized in the short term by retrofitting less energy efficient and larger homes, timber or steel frame homes and houses rather and apartments. The types of retrofits leading to the greatest surplus for both household and grant provider include cavity wall insulation paired with either a boiler with heating controls or heating controls only retrofit.  相似文献   
103.
长久以来,前辈学人对于《史记》中平阳君赵豹“秦以牛田(之)水通粮”一语解释多有不同,或以为是秦“以牛耕田,以水漕粮”,或以为是秦“以发源于‘牛田’之地的河流进行漕粮”,但均未形成定论。本文认为,先秦时期关中水资源丰富,渭河支流多可航运,加上关中水利发达,于是秦国利用与渭河支流连通的田间大渠——“浍”渠进行粮食漕运,即所谓“秦以牛田水通粮”。且战国后期,随着秦对外战争规模的扩大,粮秣耗费日增,使用“牛田水通粮”已十分必要。  相似文献   
104.
This article explores the rhetoric of four energy transitions. It begins by summarising research on the intersection of fantasy, technology and the sociology of expectation. It then looks at how ideas of progress, modernity, cheapness, abundance and hope influence the way society perceives new energy technologies, causing them to overestimate benefits and underestimate challenges. Our rhetorical analysis finds in case studies of steam engines, gasoline automobiles, hydroelectric dams and nuclear reactors that newly ‘discovered’ sources of energy or newly invented technologies are always assumed to provide infinitely abundant energy and to have the potential to create positive utopian changes in society. We conclude by noting the salient implications of these rhetorical themes for energy planners, analysts and scholars.  相似文献   
105.
This study investigates the impact of low-cost carriers (LCCs) on Saudi Arabia's tourism demand. It also provides an understanding of the relationship between air transport development and tourism development in the Gulf region. The Box–Jenkins SARIMA-X models were employed to model and forecast international tourist arrivals to Saudi Arabia, using monthly international tourist arrivals to Saudi Arabia from July 2010 to December 2015. The forecasting models were significantly accurate, with lower values of MAPE, MAP, and RMSE. The findings suggest that an increase in airline capacity, religious travel, and airline competition are associated with the increasing international tourist arrivals to Saudi Arabia. This also indicates that there is a positive relationship between air transport development and tourism development. Further aviation liberalisation in the Gulf region is discussed to give opportunities for the region's LCCs to increase their share of the increasing air travel demand, thereby enhancing tourism development.  相似文献   
106.
When default leads to exclusion from financial markets, the implied loss of consumption smoothing opportunities is more costly when income volatility is high. A rise in income risk thus makes default less attractive, allowing creditors to relax borrowing limits. I show how, in an open economy, this endogenous financial deepening may reduce aggregate foreign assets in response to a rise in individual income risk, against the precautionary savings intuition. Conditions for this depend on whether default constrains complete or uncontingent contracts. The post-1980 rise in US household income risk strongly reduces foreign assets when domestic markets are complete or world interest rates low.  相似文献   
107.
山秋月  吴永强 《科技和产业》2023,23(14):223-227
针对全货运航空公司,研究其货运航线网络的构建问题。基于单分配严格枢纽航线网络,对传统模型进行改进。以各航线上货物的委托运输成本和自有机队的运输成本,取代传统的单位运输成本和折扣因子,考虑枢纽点的中转成本和载运率对路径选择的影响。结合航空货运夜航的特征考虑各机队夜间可用时间的限制,以总成本最小为目标,构建数学模型,采用LINGO优化软件求解,验证模型的有效性,为全货运航空公司构建货运航线网络提供参考。  相似文献   
108.
This article explores the role of regulation as a supporting institution for an energy market. Two aspects are examined: first, the role of regulation in promoting a competitive market for the retail supply of energy, and second, the role of regulation in providing access to the transmission and distribution networks, assumed to be monopolies, that provide services for the retail suppliers. UK regulation promoted retail energy competition until 2008, but in that year changed direction, and since then has been restricting retail competition. In contrast, UK regulation since 2008 has encouraged more customer engagement in the network part of the energy sector. This offers the prospect, at least, of the emergence of a form of competition and choice in the process of setting price controls.  相似文献   
109.
董立伯 《价值工程》2014,(16):26-27
对唐钢南厂区运输与仓储设施存在的问题进行了分析和总结。针对存在的不足,按照厂内运输系统优化的原则,从铁路站场改造、扩大仓储能力以及铁路运输设备重载化、专用化等方面提出运输方案及改造措施并实施,从而增强了唐钢南厂区的运输能力,提高了产品发运的物流服务水平。  相似文献   
110.
This paper empirically investigates the main drivers of airline network concentration in an air transport market subject to rapid growth. We consider the Brazilian air transport industry of the 2000s, in which network concentration rapidly increased and was followed by a period of massive flight delays and cancelations, which resulted in the “big blackout” of 2006–2007. We develop an econometric model of network concentration, accounting for demand, cost and competition variables that may affect the propensity of carriers to concentrate flights and passenger connections on a few airports of a network. The main focus of the paper is on the relation between networks leading to the problems of the blackout episode. We investigate the dynamic pattern of the evolution of concentration before and after the abnormal period of operations and find that concentration began to rise at least six quarters before, and persisted at a high level until two quarters after the blackout – and then plunged steeply toward the end of the decade. We believe that our analysis contributes to an improved understanding of the behavior of air transport systems subject to network concentration and congestion. With respect to methodology, we suggest and employ the use of alternative measures of network concentration to check the robustness and validity of our results.  相似文献   
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