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991.
Top-down power system restoration following a widespread blackout begins with energization of the backbone transmission network. All interconnected regions will be restored as a whole, which needs collaboration of multiple operators. The parallel control and integrated restoration planning issues have to be addressed. In order to conduct an efficient top-down restoration process and guarantee the operational security, a hierarchical coordination mechanism and an online decision support system-based self-healing approach are proposed. Considering the multiple decision-making problems involved, an associated bi-level optimization model is built, which integrates the planning problems of backbone reconfiguration, sub-transmission system restoration, and non-black-start units start-up. Then, a solution methodology is developed to provide online decisions based on the model. Simulation results of Shandong Power System in China show that the restoration performance is significantly improved using the proposed control approach. Additionally, the decision method is proved to be efficient enough for online applications. 相似文献
992.
993.
当前存在的云模型相似性度量仅局限于单粒度空间,缺乏多粒度云模型的相似性度量的相关研究.因此,文中首先证明知识距离框架的相关性质,并建立知识距离与信息度量、信息粒度之间的联系,在分层递阶粒结构上得到如下结论:同一粒结构中粒空间的粒度差异正相关于知识距离,通过知识距离可将随粒度连续变化的粒空间映射到一维坐标上.最后,在知识距离框架的基础上提出云模型相似性度量方法.实验验证上述结论在云模型粒空间上成立. 相似文献
994.
针对当前基于距离测度学习的行人再识别算法中因训练样本少而出现的过拟合问题,提出正则化独立测度矩阵的行人再识别算法.该算法首先在4个不同的颜色空间单独学习测度矩阵,然后分别对相应的测度矩阵进行正则化,测试样本通过正则化后的测度矩阵进行相似性度量,最后结合相似性度量结果得到最终相似度.实验表明,相比原有算法,文中算法在性能上有进一步提升,并可改善训练样本少时出现的过拟合问题. 相似文献
995.
A short study on bromination of multiwalled carbon nanotubes (MWCNTs) through new and convenient methods was reported. Bromine (Br) is chemically attached on MWCNTs surfaces through electrophilic addition and radical reactions using N-Bromosuccinimide (NBS), NH4NO3/NBS and Br2 under thermal and UV conditions. Functionalized CNTs with Bromine groups, were characterized by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), scanning electron microscopy and X-ray diffraction (XRD) methods. 相似文献
996.
《Energy Policy》2016
This paper aims to offer an advanced assessment methodology for sustainable national energy-environment-economic efficiency strategies, based on an extended Data Envelopment Analysis (DEA). The use of novel efficiency-improving approaches based on DEA originates from the so-called Distance Friction Minimisation (DFM) method. To design a feasible improvement strategy for low-efficiency DMUs, we develop here a Target-Oriented (TO) DFM model. However, in many real-world cases input factors may not be flexibly adjusted in the short run. In this study, we integrate the TO-DFM model with a fixed (inflexible) factor (FF) approach to cope with such more realistic circumstances. Super-efficiency DEA is next used in our comparative study on the efficiency assessment of energy-environment-economic targets for the EU, APEC and ASEAN (A&A) countries, employing appropriate data sets from the years 2003 to 2012. We consider two inputs (primary energy consumption and population) and two outputs (CO2 and GDP), including a fixed input factor (viz. population). On the basis of our DEA analysis results, EU countries appear to exhibit generally a higher efficiency than A&A countries. The above-mentioned TO-DFM-FF projection model is able to address realistic circumstances and requirements in an operational sustainability strategy for efficiency improvement in inefficient countries in the A&A region. 相似文献
997.
Supplier selection is a decision-making process to identify and evaluate suppliers for making contracts. Here, we use interval type-2 fuzzy values to show the decision makers’ preferences and also introduce a new formula to compute the distance between two interval type-2 fuzzy sets. The performance of the proposed distance formula in comparison with the normalized Hamming, normalized Hamming based on the Hausdorff metric, normalized Euclidean and the signed distances is evaluated. The results show that the signed distance has the same trend as our method, but the other three methods are not appropriate for interval type-2 fuzzy sets. Using this approach, we propose a hierarchical clustering-based method to solve a supplier selection problem and find the proximity of the suppliers. To illustrate the applicability of the proposed method, first a case study of supplier selection problem with 8 criteria and 8 suppliers are illustrated and next, an example taken from the literature is worked through. Then, to test the hierarchical clustering-based method and compare with the obtained results by two other methods, a comparative study using experimental analysis is designed. The results show that while the proposed hierarchical clustering algorithm provides acceptable results, it is also conveniently appropriate for using interval type-2 fuzzy sets and obtaining proximity of suppliers. 相似文献
998.
Nelly Olivier-Maget Gilles Htreux Jean Marc Le Lann Marie Vronique Le Lann 《Computers & Chemical Engineering》2009,33(10):1617
The complexity and the size of the industrial chemical processes induce the monitoring of a growing number of process variables. Their knowledge is generally based on the measurements of system variables and on the physico-chemical models of the process. Nevertheless, this information is imprecise because of process and measurement noise. So, the research ways aim at developing new and more powerful techniques for the detection of process fault. This article presents a method for the fault detection based on the comparison between the reference model evolution and the real system generated by the extended Kalman filter. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. It is a general object-oriented environment which provides common and reusable components designed for the development and the management of dynamic simulation of industrial systems. The use of this method is illustrated through a didactic example relating to the field of Chemical Process System Engineering. 相似文献
999.
《Measurement》2014
The paper presents the design and the experimental evaluation of prototypes of measurement nodes that are part of the Wireless Active Guardrail System (WAGS). The WAGS is an innovative infrastructure, allowing increasing traffic safety on roads, by monitoring vehicle speed, proximity between vehicle and guardrail, impact of a vehicle with the guardrail, and several environmental parameters. In particular, in this paper, the designs and prototypes of the nodes dealing with speed and proximity measurements are presented. Then, all the phases of their experimental evaluation are reported and discussed. 相似文献
1000.