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1.
风力发电技术经济分析及对策 总被引:2,自引:0,他引:2
介绍了中、美等6个国家的电力构成以及世界风能资源的分布,并对世界风能资源经济效益进行了分析,阐述了风力发电的前景,指出了我国风电产业存在的问题,并提出发展我国风电产业的建议:研发大型风电机组,强化环保法规及给予风电产业以优惠政策. 相似文献
2.
洪永稳 《安徽农业大学学报(社会科学版)》2008,17(5):73-75
“物感说”是中国文论史上关于文艺的本源论和生成论。《淮南子》和《乐记》分别从道、儒两家不同的思想体系立论,对其都作了具体的论述,两家有相同的观点也有相异的看法,对后世都产生了相应的影响。 相似文献
3.
A quantitative criterion for ranking the different scenarios of nuclear and radiological terrorism has been developed. The aim of the model is not to predict terroristic events but only to indicate which scenario has the higher utility from the point of view of a terroristic organization in terms of balance between factors favoring and discouraging the attack, respectively. All these factors were quantified according to a scoring system that takes into account the logarithmic relationship between perceptions and stimuli. The criterion was applied to several scenarios, each of which was modeled in a simple but not trivial way in order to estimate the expected damage in terms of probable life losses from both radiative and nonradiative effects. The outcome from the ranking method indicates that the attractive scenario appears to be the detonation of a low yield improvised nuclear device in the metropolitan area of a major city. 相似文献
4.
一些恒等式在函数论、组合数学、解析数论等学科的研究领域中极为重要。以二项式作为生成函数,给出了几个组合恒等式证明。 相似文献
5.
This paper presents a genetic algorithm (GA) for parallel redundancy optimization in series-parallel power systems exhibiting
multi-state behavior, optimizing the reliability subject to constraints. The components are binary and chosen from a list
of products available in the market, and are being characterized by their feeding capacity, reliability, cost and weight.
System reliability is defined as the ability to satisfy consumer demand and is presented as a piecewise cumulative load curve.
In GA, to handle infeasible solutions penalty strategies are used. Penalty technique keep a certain amount of infeasible solutions
in each generation so as to enforce genetic search towards an optimal solution from sides of, both, feasible and infeasible
regions. We here present a dynamic adaptive penalty function which helps the algorithm to search efficiently for optimal/near
optimal solution. To evaluate system reliability, a fast procedure, based on universal generating function, is used. An example
considering a multi-state series-parallel power system is solved considering both homogeneous and heterogeneous types of redundancy.
Also an example considering price discounts is solved. The effectiveness of the penalty function and the proposed algorithm
is studied and shown graphically. 相似文献
6.
In this paper, a new generalization of alpha-skew-normal distribution is considered. Some properties of this distribution, which is denoted by GASN(α, λ), including moments, maximum likelihood estimation of parameters, and some other properties are studied. Finally, using a real data set, we show that our new distribution is the best-fitted distribution for the used data among normal, skew normal, alpha-skew-normal, and skew-bimodal-normal distributions. 相似文献
7.
陈星 《北京联合大学学报(人文社会科学版)》2012,(3):87-92
随着两岸关系和平发展的持续推进,这项战略已经产生了强大的溢出效应。影响所及,两岸关系结构、台湾民众对两岸关系的认知结构以及台湾岛内话语结构等都发生了根本性变化,这种局面对岛内政党政治的基本生态和未来发展趋势产生了较大影响,两个主要政党都针对环境的变化进行了一定的调整,以求适应台海局势的结构性变化,谋求未来更多的发展空间。 相似文献
8.
《Journal of Statistical Computation and Simulation》2012,82(7):951-979
For any continuous baseline G distribution [G.M. Cordeiro and M. de Castro, A new family of generalized distributions, J. Statist. Comput. Simul. 81 (2011), pp. 883–898], proposed a new generalized distribution (denoted here with the prefix ‘Kw-G’ (Kumaraswamy-G)) with two extra positive parameters. They studied some of its mathematical properties and presented special sub-models. We derive a simple representation for the Kw-G density function as a linear combination of exponentiated-G distributions. Some new distributions are proposed as sub-models of this family, for example, the Kw-Chen [Z.A. Chen, A new two-parameter lifetime distribution with bathtub shape or increasing failure rate function, Statist. Probab. Lett. 49 (2000), pp. 155–161], Kw-XTG [M. Xie, Y. Tang, and T.N. Goh, A modified Weibull extension with bathtub failure rate function, Reliab. Eng. System Safety 76 (2002), pp. 279–285] and Kw-Flexible Weibull [M. Bebbington, C.D. Lai, and R. Zitikis, A flexible Weibull extension, Reliab. Eng. System Safety 92 (2007), pp. 719–726]. New properties of the Kw-G distribution are derived which include asymptotes, shapes, moments, moment generating function, mean deviations, Bonferroni and Lorenz curves, reliability, Rényi entropy and Shannon entropy. New properties of the order statistics are investigated. We discuss the estimation of the parameters by maximum likelihood. We provide two applications to real data sets and discuss a bivariate extension of the Kw-G distribution. 相似文献
9.
针对碳减排后普遍存在的发电成本垂直差异电力市场及其显著的大用户电量偏好差异,本文提出概率性电量供给以及与之对应的概率发电,并利用价格杠杆调控发电商低碳发电尤其高发电成本发电机会与供给效能不足.先后构建发电成本内、外生选择下的概率发电模型,求解发电商的电量供给均衡并分析概率发电策略的最优性.最后,将发电成本内生选择模型拓展到分解市场需求不确定性的概率发电模型.研究发现:相比基准发电,概率发电可以作为一种有利可图的发电容量过剩的解决方法,即使在发电成本内生选择时也是可行的;当发电商采用“强”成本差异的发电策略时,引入折中的概率发电会让产品线上成本水平相互更接近,且大用户的消费者剩余得到提高;与此相反,在市场中实施“弱”成本差异发电,发电商利用概率发电则增大成本分离并降低大用户的消费者剩余;在不确定性市场需求下,当偏好低发电成本电量的大用户对单位发电成本的估价相对于偏好高发电成本电量的大用户对单位发电成本的估价足够高时,概率发电可以以一种管理不利需求状况工具的身份出现. 相似文献
10.
Order statistics from trivariate normal and -distributions in terms of generalized skew-normal and skew- distributions 总被引:1,自引:0,他引:1
We consider here a generalization of the skew-normal distribution, GSN(λ1,λ2,ρ), defined through a standard bivariate normal distribution with correlation ρ, which is a special case of the unified multivariate skew-normal distribution studied recently by Arellano-Valle and Azzalini [2006. On the unification of families of skew-normal distributions. Scand. J. Statist. 33, 561–574]. We then present some simple and useful properties of this distribution and also derive its moment generating function in an explicit form. Next, we show that distributions of order statistics from the trivariate normal distribution are mixtures of these generalized skew-normal distributions; thence, using the established properties of the generalized skew-normal distribution, we derive the moment generating functions of order statistics, and also present expressions for means and variances of these order statistics.Next, we introduce a generalized skew-tν distribution, which is a special case of the unified multivariate skew-elliptical distribution presented by Arellano-Valle and Azzalini [2006. On the unification of families of skew-normal distributions. Scand. J. Statist. 33, 561–574] and is in fact a three-parameter generalization of Azzalini and Capitanio's [2003. Distributions generated by perturbation of symmetry with emphasis on a multivariate skew t distribution. J. Roy. Statist. Soc. Ser. B 65, 367–389] univariate skew-tν form. We then use the relationship between the generalized skew-normal and skew-tν distributions to discuss some properties of generalized skew-tν as well as distributions of order statistics from bivariate and trivariate tν distributions. We show that these distributions of order statistics are indeed mixtures of generalized skew-tν distributions, and then use this property to derive explicit expressions for means and variances of these order statistics. 相似文献