The use of electric vehicles is increasing year by year, and a large number of them are connected to the distribution network, which has a negative impact on the normal operation of the power grid. By optimizing the c...
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ISBN:
(纸本)9781665479141
The use of electric vehicles is increasing year by year, and a large number of them are connected to the distribution network, which has a negative impact on the normal operation of the power grid. By optimizing the configuration of charging facilities, the economy of the construction of charging facilities and the stability of the operation of the distribution network can be realized. This paper uses crisscross optimization algorithm (CSO) to select the location and capacity of the electric vehicle charging facilities. The upper layer considers its construction cost and operation and maintenance cost, and also considers the transportation cost from the users of each node to the nearest configured node;the lower layer will configure the location based on the configuration result of the upper layer. The stable and economic operation of the power grid is also introduced into the location and capacity of charging facilities, considering the influence of the power distribution network loss and voltage offset, and achieving the optimal configuration of charging facilities through the joint action of the upper and lower layers. Through the coupling of the 33-node system and the 25-node transportation system, the location and capacity of electric vehicle charging facilities are selected, which verifies the effectiveness and feasibility of the proposed method.
Wind speed forecasting is of great significance for wind farm management and safe integration into electric power grid. As wind speed is characterized by high autocorrelation and inherent volatility, it is difficult t...
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Wind speed forecasting is of great significance for wind farm management and safe integration into electric power grid. As wind speed is characterized by high autocorrelation and inherent volatility, it is difficult to predict with a single model. The aim of this study is to develop a new hybrid model for predicting the short wind speed at 1 h intervals up to 5 h based on wavelet packet decomposition, crisscross optimization algorithm and artificial neural networks. In the data pre-processing phase, the wavelet packet technique is used to decompose the original wind speed series into subseries. For each transformed components with different frequency sub-bands, the back-propagation neural network optimized by crisscross optimization algorithm is employed to predict the multi-step ahead wind speed. The eventual predicted results are obtained through aggregate calculation. To validate the effectiveness of the proposed approach, two wind speed series collected from a wind observation station located in the Netherlands are used to do the multi-step wind speed forecasting. To reduce the statistical errors, all forecasting methods are executed 50 times independently. The results of this study show that: (1) the proposed crisscross optimization algorithm has significant advantage over the back-propagation algorithm and particle swarm optimization in addressing the prematurity problems when applied to train the neural network. (2) Compared with the previous hybrid models used in this study, the proposed hybrid model consistently has the minimum mean absolute percentage error regardless of one-step, three step or five-step prediction. (C) 2016 Elsevier Ltd. All rights reserved.
Distributed generation (DG) systems are integral parts in future distribution networks. In this paper, a novel approach integrating crisscross optimization algorithm and Monte Carlo simulation (CSO-MCS) is implemented...
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Distributed generation (DG) systems are integral parts in future distribution networks. In this paper, a novel approach integrating crisscross optimization algorithm and Monte Carlo simulation (CSO-MCS) is implemented to solve the optimal DG allocation (ODGA) problem. The feature of applying CSO to address the ODGA problem lies in three interacting operators, namely horizontal crossover, vertical crossover and competitive operator. The horizontal crossover can search new solutions in a hypercube space with a larger probability while in the periphery of each hypercube with a decreasing probability. The vertical crossover can effectively facilitate those stagnant dimensions of a population to escape from premature convergence. The competitive operator allows the crisscross search to always maintain in a historical best position to quicken the converge rate. It is the combination of the double search strategies and competitive mechanism that enables CSO significant advantage in convergence speed and accuracy. Moreover, to deal with system uncertainties such as the output power of wind turbine and photovoltaic generators, an MCS-based method is adopted to solve the probabilistic power flow. The effectiveness of the CSO-MCS method is validated on the typical 33-bus and 69-bus test system, and results substantiate the suitability of CSO-MCS for multi-objective ODGA problem.
DED (Dynamic economic dispatch) considering valve-point effects is a complicated non-convex optimization problem in power system. For large-scale DED problem with hundreds of generators, how to avoid the curse of dime...
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DED (Dynamic economic dispatch) considering valve-point effects is a complicated non-convex optimization problem in power system. For large-scale DED problem with hundreds of generators, how to avoid the curse of dimensionality remains a big challenge due to the exponential growth of search space. In allusion to this problem, this paper presents a promising heuristic approach named CSO (crisscrossoptimization) algorithm, which generates high quality solutions in large space by applying two interacting search operators, namely horizontal crossover and vertical crossover. The former has powerful global search ability while the latter can effectively alleviate the premature convergence problem. Their combination leads to a magical effect on improving solution quality and convergence rate especially for large-scale DED problems with valve-point effects. The feasibility and effectiveness of the proposed CSO algorithm is validated by seven test systems consisting of different numbers of generators. The results are compared with those of other heuristic methods reported in the literature. It is shown that the proposed method is capable of yielding higher quality solutions. To examine the availability of CSO in large power system, three new systems with 200-1000 generators are also tested, the obtained results confirm its suitability for large-scale DED problem. (C) 2015 Elsevier Ltd. All rights reserved.
As cogeneration plays an increasingly important role in energy utilization, the combined heat and power economic dispatch (CHPED) becomes an important task in power system operation. In this paper, a novel crisscross ...
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As cogeneration plays an increasingly important role in energy utilization, the combined heat and power economic dispatch (CHPED) becomes an important task in power system operation. In this paper, a novel crisscrossoptimization (CSO) algorithm is implemented to solve the large scale CHPED problem, which is a challenging non-convex optimization problem with a large number of local minima. The feature of applying CSO to address the CHPED problem lies in two interacting operators, namely horizontal crossover and vertical crossover. The horizontal crossover searches for the new solutions within a half population of hyper-cubes with a large probability while in their respective peripheries with a decreasing probability. The vertical crossover provides a effective mechanism for those stagnant dimensions of a population to escape from premature convergence. The combination of both gifts CSO with a powerful global search ability. The effectiveness of the proposed method is validated on six cogeneration systems with different characteristics. The numeric results demonstrates that the proposed CSO method achieves much better results than other methods reported in the literature. To investigate the robustness and applicability of CSO in large power system, two new systems with 96 and 192 units by duplicating the system of case 4 two times and four times are also studied. The results obtained substantiates the suitability of CSO for large-scale constrained CHPED problem. (C) 2015 Elsevier Ltd. All rights reserved.
Obtaining the optimal travel time on dynamic traffic assignment(DTA) is very important for intelligent traffic system (ITS). A lot of approaches have been applied for DTA to make the travel time costing least, but cur...
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ISBN:
(纸本)9781509039067
Obtaining the optimal travel time on dynamic traffic assignment(DTA) is very important for intelligent traffic system (ITS). A lot of approaches have been applied for DTA to make the travel time costing least, but current algorithms cannot be solved to guarantee optimality. In this paper, a method based on crisscross optimization algorithm(CSO) is introduced to solve DTA problem. This novel algorithm adopts a double-crisscross search mechanism. It differs from algorithms given in introduction. It uses crisscross programming to enhance performance. This paper aims at time-varying flows in dynamic system optimal model and using CSO algorithm to solve it. At last, we obtain traffic flow distribution data by designing a numerical example and employing simulation. We realized this algorithm converges to the optimal final solution.
How to improve the global search ability without significantly impairing the convergence speed is still a big challenge for most of the meta-heuristic optimizationalgorithms. In this paper, a concept for the optimiza...
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How to improve the global search ability without significantly impairing the convergence speed is still a big challenge for most of the meta-heuristic optimizationalgorithms. In this paper, a concept for the optimization of continuous nonlinear functions applying crisscross optimization algorithm is introduced. The crisscross optimization algorithm is a new search algorithm inspired by Confucian doctrine of gold mean and the crossover operation in genetic algorithm, which has distinct advantages in solution accuracy as well as convergence rate compared to other complex optimizationalgorithms. The procedures and related concepts of the proposed algorithm are presented. On this basis, we discuss the behavior of the main search operators such as horizontal crossover and vertical crossover. It is just because of the perfect combination of both, leading to a magical effect on improving the convergence speed and solution accuracy when addressing complex optimization problems. Twelve benchmark functions, including unimodal, multimodal, shifted and rotated functions, are used to test the feasibility and efficiency of the proposed algorithm. The experimental results show that the crisscross optimization algorithm has an excellent performance on most of the test functions, compared to other heuristic algorithms. At the end, the crisscross optimization algorithm is successfully applied to the optimization of a large-scale economic dispatch problem in electric power system. It is concluded that the crisscross optimization algorithm is not only robust in solving continuous nonlinear functions, but also suitable for addressing the complex real-world engineering optimization problems. (C) 2014 Elsevier B.V. All rights reserved.
The persistently high incidence of breast cancer emphasizes the need for precise detection in its ***-aided medical systems are designed to provide accurate information and reduce human errors,in which accurate and ef...
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The persistently high incidence of breast cancer emphasizes the need for precise detection in its ***-aided medical systems are designed to provide accurate information and reduce human errors,in which accurate and effective segmentation of medical images plays a pivotal role in improving clinical *** Threshold Image Segmentation(MTIS)is widely favored due to its stability and straightforward *** when dealing with sophisticated anatomical structures,high-level thresholding is a crucial technique in identifying fine *** enhance the accuracy of complex breast cancer image segmentation,this paper proposes an improved version of RIME optimizer EECRIME,denoted as the double Enhanced solution quality crisscross RIME *** original RIME initially conducts an efficient optimization to target promising *** double-enhanced solution quality(EESQ)mechanism is proposed for thorough exploitation without falling into local *** contrast,the crisscross operations perform a further local exploration of the generated feasible *** performance of EECRIME is verified with basic and advanced algorithms on IEEE CEC2017 benchmark ***,an EECRIME-based MTIS method in combination with Kapur’s entropy is applied to segment breast Infiltrating Ductal Carcinoma(IDC)histology *** results demonstrate that the developed model significantly surpasses its competitors,establishing it as a practical approach for complex medical image processing.
In this paper, an enhanced hybrid chameleon swarm algorithm (CSA) is proposed and applied to the degree reduction problem of disk Wang-Ball (DWB) curve. CSA is a novel population-based algorithm inspired by the huntin...
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In this paper, an enhanced hybrid chameleon swarm algorithm (CSA) is proposed and applied to the degree reduction problem of disk Wang-Ball (DWB) curve. CSA is a novel population-based algorithm inspired by the hunting behavior of chameleons, its simplicity and easy implementation make it applied to different fields. However, it suffers from premature convergence and easy to fall into local optimum, especially in the face of complex optimization problems. Therefore, this paper proposes an enhanced hybrid CSA (CCECSA, for short). Compared with the classic CSA, the proposed CCECSA mainly introduces three improvements: (1) The crisscross optimization algorithm is mixed to avoid premature convergence, in which the horizontal and vertical crossover can generate moderation solutions to increase the diversity of the population. (2) Elite guidance mechanism is introduced to speed up the convergence. (3) Competitive substitution mechanism is added to replace the worst individual, and an interference strategy is set to prevent the algorithm from falling into a local optimum. The efficiency and robustness of the proposed CCECSA are demonstrated by the comparison results with some advanced meta-heuristic algorithms on CEC2014, CEC2017, and 4 engineering design examples. In addition, for the degree reduction problem of DWB curves, the multi-degree reduction optimization models of its center curve and radius function are established respectively. At the same time, the optimal center curve and radius function of the approximating DWB curves of lower degree are obtained by the proposed CCECSA. The experimental results show that the proposed CCECSA achieves the optimal solution with better convergence and robustness. The source code of CCECSA is publicly available in the supplementary material related to this article.(c) 2022 International Association for Mathematics and Computers in Simulation (IMACS). Published by Elsevier B.V. All rights reserved.
Accurate wind power forecasting is of great significance for power system operation. In this study, a triple-stage multi-step wind power forecasting approach is proposed by applying attention-based deep residual gated...
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Accurate wind power forecasting is of great significance for power system operation. In this study, a triple-stage multi-step wind power forecasting approach is proposed by applying attention-based deep residual gated recurrent unit (GRU) network combined with ensemble empirical mode decomposition (EEMD) and crisscross optimization algorithm (CSO). In the data processing stage, the EEMD is used to decompose the wind power/speed time series and a bi-attention mechanism (BA) is applied to enhance the sensitivity of model to the important information from both time and feature dimension. In the prediction stage, a series-connected deep learning model called RGRU consisting of the residual network and GRU is proposed as the forecasting model, aiming to make full use of extracting the static and dy-namic coupling relationship among the input features. In the retraining-stage, a high-performance CSO algorithm is adopted to further optimize the fully-connected layer of RGRU model so as to improve the generalization ability of the model. The proposed method is validated on a wind farm located in Spain and the experimental results demonstrate that the proposed hybrid model has significant advantage over other state-of-the-art models involved in this study in terms of prediction accuracy and stability. (c) 2021 Elsevier Ltd. All rights reserved.
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