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61.
静态安全约束下基于Benders分解算法的可用传输容量计算 总被引:22,自引:8,他引:22
在电力市场环境下,可用传输容量(ATC)是反映输电线路可用于交易的剩余容量的重要指标。文中以最优潮流为基础,采用Benders分解方法将考虑静态安全约束的ATC计算问题分解为一个基态主问题和一系列与各预想事故有关的子问题。主问题用来处理基态潮流和相应约束以及由子问题所返回的Benders割(cut)约束,而各子问题用来处理各预想事故和形成相应的静态安全约束。文章给出了相应的数学模型,并提出了两种改进的求解策略。4节点和IEEE30节点系统的计算结果表明了该方法和求解策略的有效性。 相似文献
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Rhode Heyns G. Weiss Schwaibold Steingroever Hans Müller Kanitz H. J. Steinbeck K. Felix K. Höll P. de Fremery Edward Hofmann Konrad Lang O. Windhausen Trendtel W. Leithe W. Schulze Ilse Gaede v. Noël Jesser H. Elsner Pieper W. Schreiber Rudolf Abderhalden Renate Teske Hanson I. Stahn Krzywanek Fr. Bartschat Lars Erlandsen Ad. Hanak W. Bartels Kluge E. -E. Bauke Karl Bernhard G. Steinhoff W. Hämmerle C. I. Kruisheer Brüning Reichard K. J. Demeter M. Gordienko Flössner Jahr Diemair H. Mohler 《European Food Research and Technology》1939,78(1):48-112
65.
Leila Sharifi Llorenç Cerdà-Alabern Felix Freitag Luís Veiga 《Journal of Grid Computing》2016,14(2):299-325
The cost of power and its associated delivery are becoming significant factors in the total expenditure of large-scale data centers. Numerous techniques have been proposed to address the energy efficiency issue in cloud systems. Recently, some efforts have been made to decentralize the cloud via distributing data centers in diverse geographical positions, at different scales. In this paper, we elaborate on the energy effectiveness of service provisioning on different cloud architectures, from a mega-data center to a nano data center, which provides the extreme decentralization in terms of cloud architecture, as well as P2P-clouds or community network clouds. We study the energy consumption through an analytical and simulation framework for video streaming and MapReduce applications. 相似文献
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The authors of this paper review how complex entities, composed of many interdependent subsystems, such as international rail operators, can improve their ability to recover from incidents through the better management of key interfaces. The principles of Normal Accident Theory and resilience engineering are discussed, and the case study of the Eurostar incident of 18–19 December 2009 is considered in detail. Lessons learnt from resilience engineering are applied to the case study to extract recommendations by which incident management for open access international rail transport may be improved. 相似文献
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This paper shows that a turned trochoidal function disturbance may lead to peripheral drops production. The resulting model is used to describe that a turned trochoidal disturbance leads to peripheral drops production on the liquid jet surface without the necessity for superimposed disturbances. The trochoid is a non-unique parametric function. Only non-unique parametric functions disturbances may lead to peripheral drops production. The trochoidal function disturbance is decomposed to Fourier series. Every Fourier element receives an amplification factor in accordance to the Rayleigh inviscid jet model. Peripheral drops are received on the jet surface. The paper shows that all trochoidal disturbance functions, prolate cycloid, cycloid and curtate cycloid have a capability of peripheral drops producing. A limited capability of peripheral drops production is introduced for the trochoidal curtate cycloid. Produced drops size are reduced for increasing the jet velocity and wave number. Smaller drops are also received by transition from the prolate cycloid to curtate cycloid disturbance. 相似文献
70.
Felix Kogan Corresponding author Bangjie Yang Guo Wei Pei Zhiyuan Jiao Xianfeng 《International journal of remote sensing》2013,34(11):2325-2336
Weather‐related crop losses have always been a concern for farmers, governments, traders and policy makers for the purpose of balanced food supplies, demands, trade, and distribution of aid to nations in need. Therefore, early crop loss assessment in response to weather fluctuations is an important issue. This paper discusses the utility of Advanced Very High Resolution Radiometer (AVHRR)‐based vegetation health indices as a proxy for modelling corn yield and for early warning of drought‐related losses of agricultural production in China. The indices were tested in Jilin province on corn yield during 1982–2001 using correlation and regression analysis. A strong correlation between corn yield and the vegetation health indices were found during the critical period of corn growth, which starts 2–3 weeks before and 2–3 weeks after corn tassel. Following the results of correlation analysis, several regression equations were constructed where vegetation health indices were used as independent variables. The estimates of corn yield can be carried out well in advance of harvest and the errors of the estimates are 7–10%. The errors become smaller when the estimations are related to losses in corn yield due to drought. 相似文献