An options pricing approach to ramping rate restrictions at hydro power plants

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.     

A STRUCTURAL RISK‐NEUTRAL MODEL FOR PRICING AND HEDGING POWER DERIVATIVES

We develop a structural risk‐neutral model for energy market modifying along several directions the approach introduced in Aïd et al. In particular, a scarcity function is introduced to allow important deviations of the spot price from the marginal fuel price, producing price spikes. We focus on pricing and hedging electricity derivatives. The hedging instruments are forward contracts on fuels and electricity. The presence of production capacities and electricity demand makes such a market incomplete. We follow a local risk minimization approach to price and hedge energy derivatives. Despite the richness of information included in the spot model, we obtain closed‐form formulae for futures prices and semiexplicit formulae for spread options and European options on electricity forward contracts. An analysis of the electricity price risk premium is provided showing the contribution of demand and capacity to the futures prices. We show that when far from delivery, electricity futures behave like a basket of futures on fuels.     

浅谈施工现场临时用电安全防护措施

分析了在油气田建设工程施工阶段,临时用电存在的设备陈旧、安全管理不到位、保护接地线不按要求连接等安全隐患,提出了安全用电的具体防护措施。     

产品市场定位与消费者忠诚之间的关系——基于浙江产品市场势力调查问卷

以2011年浙江省商务厅向各地市县发放的浙江产品市场势力调查问卷为数据来源,以其中的119家浙江省内商业企业作为研究样本,对浙江产品的市场定位与消费者忠诚之间的关系进行了实证研究。结果表明:产品市场定位与消费者的行为忠诚相关,提高产品的市场定位有利于消费者产生购买企业产品的偏好,进而促使消费者实现实际的、持续的购买行为;产品市场定位的提升尤其对产品客单价、产品销量和销售额的提升有显著的促进作用。因此,浙江企业应积极投入人力、物力,提高其产品的市场定位,以提升消费者忠诚,进而实现企业在市场中的议价能力及市场竞争力的提高。     

西方经济强国模式类型及中国特色经济发展模式的思考

历史上的九个经济强国可分为三种类型,按其特色大致分为四种崛起模式;改革开放以来,形成中的有中国特色的经济发展模式创造了世界经济发展史上奇迹;正在形成中的有中国特色的经济发展模式的已具有六个方面的本质特征;重视中国经济发展模式成长中的困境;加大制度创新,突破发展障碍。     

How does growth need strength influence employee outcomes? The roles of hope,leadership, and cultural value

Abstract

Strong growth need is essential if an employee is to be motivated to complete complex and challenging jobs. It is important for organizations to attract employees with high growth need strength and help them achieve positive outcomes. However, limited research has been conducted to examine the mechanism underlying growth need strength’s positive effect on employee outcomes. Based on hope theory, we hypothesized that hope mediates the effect of growth need strength on job performance and affective commitment by transforming employees’ general desire for personal growth into goal-related cognitive thinking, comprising both ‘will’ and ‘ways’. We further hypothesized the moderating effect of transformational leadership, and the joint moderating effect of transformational leadership and individual power distance on the relationship between growth need strength and hope. We tested our hypotheses with data from a sample of 265 subordinate–supervisor dyads from China. Data analysis results supported the mediating role of hope. We found that growth need strength has a stronger effect on hope when transformational leadership is higher, and this effect is the strongest when both transformational leadership and individual power distance are simultaneously higher. The implications of these findings for human resource management research and practice are discussed.     

The Primacy of Space in Politics: Bargaining Rights,Freedom and Power in an İstanbul Neighborhood

This article explores and theorizes the ways in which urban space and political contestations are mapped onto each other. The ethnography illustrates the multifaceted transformations in a notoriously secularist neighborhood of ?stanbul, Te?vikiye, as it first turns into a high‐consumption locality in the post‐1980s, then into a high‐conflict urban space in the new millennium on the arrival of Muslim high‐spenders, particularly headscarved women. Aiming to fill the gap left by the absence of spatial analysis from political science and political sociology, I argue that the urban neighborhood becomes central for political contestation when both government and opposition fail to protect and secure liberties and rights. Now that devout Muslims are integrated into highly contested urban sites and share bourgeois lifestyles, ordinary people act in defense of their ‘sphere’ of freedom and privacy. This new territoriality is largely symptomatic of increasing fears of losing freedom, privacy and social status. This spatial defensiveness is reinforced by people's decreasing trust in, and increasing demands from, the state for the protection and security of their rights and liberties. My overarching argument is that exclusive attention to the bipolar clash between devout Muslims and secularists under the rubric of ‘neighborhood wars’ obscures multipolar conflicts around the discontents stemming from authoritarianism and democratization.     

The synchronization club: classification of global economic groups by inequality

We find that, from 1970 to 2006, the GDPs of 181 countries are described by a log-normal with a power law tail before 1992, but by a kinked power law distribution after 1992. In the 15 years from 1992 to 2006, there are two obvious scale-free zones for annual GDPs, ranked from the largest to smallest. If the countries in each scaling region are regarded as a group, the world is divided into two groups, each with a roughly stable number of members. The power exponents of the two groups are different and hence lead to different inequalities. Therefore, the basis for classification is the macro-consistent inequality within each group. The wealth grows in a synchronous nonlinear manner within groups that have a stable wealth distribution and rank structure. If each group is considered as a club, we name it a ‘synchronization club’.     

高压变频器在电厂凝结水泵上的应用

文章论述了高压变频器在燃煤发电厂大容量电动机上应用的必要性,介绍了凝结水泵的变频改造方案,分析了高压变频器改造的经济性,为同类型发电厂的节能降耗提供了借鉴经验和参考。     

广播供电系统内高压柜双电源自备投装置的故障处理和分析

随着广播电视工程的扩建升级,高科技广播电视导航设备得到了普及应用。供电系统在供应设备电能使用方面的作用越来越显著。现代广播电视供电系统要求开关柜保持良好的功能状态,设置自检测或自报警功能模块,提前发出系统感应到的异常信号。