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151.
田辰洋 《价值工程》2015,(12):164-167
本文主要分析了高速铁路在不同的供电方式下,容易出现的问题及产生的影响,在此基础上提出了解决的措施和建议,希望通过相关的改进措施达到更好地保护铁路沿线人员和设备安全的目的。  相似文献   
152.
矿井供电系统防越级跳闸技术研究成果于2014年10月在付煤公司35/6KV变电所、井下中央变电所、南翼集中变电所、北翼集中变电所、北翼一变、东四一变、东四三变以及各变电所外围需要装表计量的配电点得到全面应用。  相似文献   
153.
《Economic Systems》2015,39(3):491-501
The present paper applies the logic of John Kenneth Gailbraith's institutional economics analysis of corporate power to inquiring into the societal role of the nonprofit sector. Building on Galbraith's insight that corporations cause subtle but pervasive societal imbalances, the paper locates the role of nonprofit organizations in compensating for these imbalances, thus showing corporations and nonprofit organizations to be mutually complementary rather than antagonistic actors. This argument is supported by Niklas Luhmann's vision of the precarious relationship between the complexity and sustainability of social systems as well as by Kenneth Boulding's analysis of the farmer and labor movement. Luhmann's and Boulding's perspectives show profit-seeking corporations to be social systems developing high technological complexity at the cost of sacrificing their societal sustainability, while the improvement of the latter constitutes the rationale of many nonprofit organizations. The same systems-theoretic logic suggests, however, that nonprofit organizations may tend to underestimate the technological complexity of implementing their mission-related activities, thereby undermining their own effectiveness.  相似文献   
154.
双电源切换装置是一级负荷和其他重要负荷等用电设备中经常使用的关键设备。随着科技发展,双电源切换装置已有多种产品和型式供用户选择。本文重点对“Y”型和“H”型双电源切换装置的原理、发展过程、特点等进行论述,为电气设计、采购、及维护人员提供技术参考。  相似文献   
155.
张朝  雷同飞 《价值工程》2015,34(9):49-51
本文主要研究了一种基于温差发电的混合动力自行车,并就其改装和发动机尾气余热利用的系统优化设计进行了集中分析,最终得出了相关结论。  相似文献   
156.
European power producers have a major influence on the EU ETS, given that both their CO2 emissions and their EUA (European Union Allowance) allocations account for more than half of the total volumes of the scheme. Fuel switching is often considered as the main short-term abatement measure under the EU ETS. It consists in substituting combined cycle gas turbines (CCGTs) for hard-coal plants in power generation. Thereby coal plants run for shorter periods, and CO2 emissions are reduced. This paper provides the first theoretical analysis of fuel switching, in a context where power plants involved are not equally efficient. We begin with a preliminary work using illustrative examples and sensitivity analyses, which enables us to observe how differences in the efficiency of power plants impact the cost of fuel switching, and how this is related to the level of switching effort. Based on this, we build a theoretical model taking into account the effect of differences in the efficiency of power plants involved in fuel switching. We also investigate the effect of the timing of fuel switching abatements, within the temporally defined environment of our dynamic model. Results demonstrate that the gas price and uncontrolled CO2 emissions act together on the carbon price. We show that the influence of the gas price on the carbon price depends on the level of uncontrolled CO2 emissions, due to heterogeneity of power plants that are used in the fuel switching process. Furthermore, we show that the time of occurrence of uncontrolled emissions matters so that shocks have a stronger impact when they occur in a period that is closed to the end of the phase.  相似文献   
157.
This study integrates recent advances in interdependence theory with the literature on commitment‐based HR practices. New research on interdependence theory suggests that differences, or asymmetries, in task dependence among organisational members can cause interests to diverge. Prior research has shown that this can negatively affect interpersonal relations, individual outcomes and team processes. However, these insights gained on the dyadic, individual and team levels of analysis have not yet been explored at the organisational level and, until now, no research had yet connected these advances in interdependence theory to the field of HRM research. Hence, the current study investigates (a) whether asymmetries in task dependence do (or do not) matter at the organisational level and affect organisational effectiveness, (b) why this relationship may work by assessing a key mediator, namely, trust climate and (c) if and how these relationships can be altered by commitment‐based HR practices. Our moderated‐mediation model was tested and fully supported by a multi‐source data set of 8,390 employees from 67 organisations.  相似文献   
158.
The purpose of this paper is to argue that the implementation of the accrual-based IPSASs in European-influenced developing and transition economy countries is not an appropriate reform unless preceded or accompanied by other, essentially managerial, reforms. The nature and extent of these prior reforms depend upon the political and cultural context and, not least, upon the power relationships within and between public institutions. The advocates of the application of the IPSASs appear not to recognize that for the reform to be effective it cannot be treated as simply a technical accounting reform, yet this is what is occurring. The issues identified in this paper are based upon the author’s practical experiences of working in many of these countries.  相似文献   
159.
夏睿 《改革与战略》2014,(5):134-136
自从中国加入世贸组织以来,我国大豆对外贸易逆差越来越大。大豆进口量逐年增长以及对进口依存度过高等现象的存在,给国内大豆种植生产带来了一定的影响。文章主要从中国大豆对外贸易的现状着手,分别从中国大豆定价权的缺失、转基因大豆对我国大豆行业的冲击、国内政策对大豆产业的支持力度不够、大豆进口管理机制有待完善等四个方面阐述了中国大豆对外贸易所存在的问题。  相似文献   
160.
This paper investigates the impact of ramping rate restrictions imposed on hydro operations to protect aquatic ecosystems. The optimal ramping decision is specified as an optimal control problem which results in a Hamilton Jacobi Bellman (HJB) equation. Electricity prices are modelled as a regime switching stochastic process. The optimal control is determined by solving the HJB equation numerically using a fully implicit finite difference approach with semi-Lagrangian time stepping. The paper focuses on the effect of ramping restrictions on a hydro plant׳s value and optimal operations, and provides an analysis of which factors cause ramping restrictions to have a greater or lesser impact on profitability. It is shown that hydro plant value is negatively affected by ramping restrictions, but the extent of the impact depends on key parameters which determine the desirability of frequent changes in water release rates. Interestingly for the case considered, value is not sensitive to ramping restrictions over a large range of restrictions. The results point to the importance of accurately modelling electricity prices in gauging the trade offs involved in imposing restrictions on hydro operators which may hinder their ability to respond to volatile electricity prices and meet peak demands.  相似文献   
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