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21.
基于油气管道第三方破坏半定量风险评估,利用已获得的大量的半定量风险值,结合物元与可拓集合理论对管道第三方破坏风险等级进行划分。通过输入第三方破坏评价指标不同的评分值,运用层次分析法对各评价指标权重赋值,计算可拓集合关联函数得到相应的风险等级,进而为管道运营单位风险管理提供理论上的决策依据。该分析方法具有较强的普适性与可操作性,能很好地结合评价人员的专业知识,综合评价管道第三方破坏的风险水平,使油气管道第三方破坏风险等级的划分更加科学合理。 相似文献
22.
浅析天然气管道运输定价 总被引:2,自引:0,他引:2
天然气管道运输定价对于天然气市场的发展有着重要的作用,我国传统的天然气定价机制不能够适应天然气管输的特性,与我国天然气市场的需求已不相适应,本文将我国现阶段的一部制天然气定价方法与国外成熟的两部制天然气定价方法相比较,为我国的天然气管输定价机制的改革提出了合理性建议。 相似文献
23.
In this article, we forecast employment growth for Germany with data for the period from November 2008 to November 2015. Hutter and Weber (2015) introduced an innovative unemployment indicator and evaluated the performance of several leading indicators, including the Ifo Employment Barometer (IEB), to predict unemployment changes. Since the IEB focuses on employment growth instead of unemployment developments, we mirror the study by Hutter and Weber (2015). It turns out that in our case, and in contrast to their article, the IEB outperforms their newly developed indicator. Additionally, consumers’ unemployment expectations and hard data such as new orders exhibit a high forecasting accuracy. 相似文献
24.
“撤县设区”能促进区域发展吗——基于浙江省1993-2013年县际面板数据的分析 总被引:1,自引:0,他引:1
本文通过对国内外学者在县(区)域经济领域十几年研究成果的梳理,整理浙江省原69(现58)个县(市)近30年经济发展的数据,对县域经济进行规模分析和产业结构分析。首次对柯布-道格拉斯生产函数模型改进,把技术增长中重要的因素,即劳动力要素的受教育程度内生化分析,并运用该模型对县域经济和"撤县设区"后区(以余杭市等为例)经济作对比研究,证明"撤县设区"的政策并没有促进区域经济的发展。 相似文献
25.
We study Arrow–Debreu equilibria for a one‐period‐two‐date pure exchange economy with rank‐dependent utility agents having heterogeneous probability weighting and outcome utility functions. In particular, we allow the economy to have a mix of expected utility agents and rank‐dependent utility ones, with nonconvex probability weighting functions. The standard approach for convex economy equilibria fails due to the incompatibility with second‐order stochastic dominance. The representative agent approach devised in Xia and Zhou (2016) does not work either due to the heterogeneity of the weighting functions. We overcome these difficulties by considering the comonotone allocations, on which the rank‐dependent utilities become concave. Accordingly, we introduce the notion of comonotone Pareto optima, and derive their characterizing conditions. With the aid of the auxiliary problem of price equilibria with transfers, we provide a sufficient condition in terms of the model primitives under which an Arrow–Debreu equilibrium exists, along with the explicit expression of the state‐price density in equilibrium. This new, general sufficient condition distinguishes the paper from previous related studies with homogeneous and/or convex probability weightings. 相似文献
26.
针对不完备信息系统条件下的辐射源威胁等级判定问题,提出了一种基于改进容差关系粗糙集(ITR-RS)的不完备信息系统辐射源威胁等级判定方法。该方法将粗糙集中的不完备信息系统理论引入辐射源威胁等级判定中,并构建一套完备的决策规则提取模型。此外,利用辨识矩阵实现对属性的约简,在降低系统所需处理数据量的同时,提高了算法的实时性;在容差关系粗糙集的基础上,提出一种改进的容差关系,在属性主、客权重相结合的基础上引入阈值来划分加权阈值容差类,得到更为合理、准确的决策规则。仿真试验及分析表明,与经典RS算法相比,所提算法的威胁等级判定正确率提高了23%,可用于信息系统不完备条件下的辐射源威胁等级判定。 相似文献
27.
This paper analyses factors determining open environmental innovation (EI) and explores the possibility of embracing their tensions to achieve integrated environmental strategic goals. Building on recent literature linking open innovation and EI, the study assumes open EI strategic goals as a multidimensional construct based on the “synergistic and interwoven nature” of four identified enabling factors, that is, partners, knowledge, benefits, and motivations. A fuzzy‐set qualitative comparative analysis (fsQCA) based on Boolean algebra is conducted to analyse a set of 186 European companies operating in the telecommunication and information and communication technology (ICT) service industries. Making important theoretical, managerial, and policy contributions, this paper offers insights into the key factors enabling open EI and the tensional relationships within and between them. In doing so, it captures the non‐linear effects among these factors and the strategic goals related to an open EI strategy. It also suggests how the paradox theory might help in addressing the tensional dilemma of open EI strategy. 相似文献
28.
We consider optional time-of-use (TOU) pricing for residential consumers, offered by a publicly regulated electricity supplier, as an alternative to a single TOU or flat rate structure. An equilibrium model explores and quantifies the effects of such pricing on welfare, consumption, and production costs. The supplier offers to each household a menu of possible rate structures obtained by maximizing a collective welfare function subject to three restrictions: Pareto efficiency, incentive compatibility, sufficiency of supplier revenue to cover costs. Simulations based on realistic calibration of the model demonstrate that optional pricing can increase overall consumer welfare and reduce average cost. 相似文献
29.
ABSTRACTThis paper seeks to compare the capabilities of assorted measures of consumer and economic sentiment in predicting the growth of household expenditure. An analysis of quarterly data on five European countries shows that for none of these can the model which incorporates the EU’s headline consumer confidence indicator be deemed to be significantly inferior to any of its seven rivals. However, the rankings of the sentiment variables are seen to be influenced by: the proportion of total spending by households that is devoted to durable goods; and the nature of the behaviour of consumption over the forecast interval. 相似文献
30.
Alexander Kunith Roman Mendelevitch Dietmar Goehlich 《International Journal of Sustainable Transportation》2017,11(10):707-720
The deployment of battery-powered electric bus systems within the public transportation sector plays an important role in increasing energy efficiency and abating emissions. Rising attention is given to bus systems using fast charging technology. This concept requires a comprehensive infrastructure to equip bus routes with charging stations. The combination of charging infrastructure and bus batteries needs a reliable energy supply to maintain a stable bus operation even under demanding conditions. An efficient layout of the charging infrastructure and an appropriate dimensioning of battery capacity are crucial to minimize the total cost of ownership and to enable an energetically feasible bus operation. In this work, the central issue of jointly optimizing the charging infrastructure and battery capacity is described by a capacitated set covering problem. A mixed-integer linear optimization model is developed to determine the minimum number and location of required charging stations for a bus network as well as the adequate battery capacity for each bus line. The bus energy consumption for each route segment is determined based on individual route, bus type, traffic, and other information. Different scenarios are examined in order to assess the influence of charging power, climate, and changing operating conditions. The findings reveal significant differences in terms of required infrastructure. Moreover, the results highlight a trade-off between battery capacity and charging infrastructure under different operational and infrastructure conditions. This paper addresses upcoming challenges for transport authorities during the electrification process of the bus fleets and sharpens the focus on infrastructural issues related to the fast charging concept. 相似文献