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基于归一分解的并行多目标Dividing Rectangles算法
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作者 李晨 陈逸东 +3 位作者 陆忠华 杨雪莹 王子田 迟学斌 《计算机研究与发展》 EI CSCD 北大核心 2024年第11期3909-3922,共14页
多目标优化问题普遍存在且难以解决,目前多采用多目标进化算法进行求解.然而,这些方法通常在种群初始化阶段和进化过程中包含随机操作以保持多样性,导致了其结果不可复现且缺乏全局收敛的理论保证.鉴于此,提出了一种基于归一分解的多目... 多目标优化问题普遍存在且难以解决,目前多采用多目标进化算法进行求解.然而,这些方法通常在种群初始化阶段和进化过程中包含随机操作以保持多样性,导致了其结果不可复现且缺乏全局收敛的理论保证.鉴于此,提出了一种基于归一分解的多目标Dividing Rectangles(DIRECT)算法,首先通过一种可较好捕捉复杂前沿的归一分解方法将原问题分解为一系列子问题,以降低问题计算复杂度;其次,采用Dividing Rectangles算法同时优化分解得到的子问题,并在优化过程中基于全局关联机制将生成的候选解分配给相应的子问题,以更好地保留优秀候选解并提高算法搜索效率;最后,证明了算法的收敛性.此外,为了进一步提高计算效率,提出了一种基于自适应关联迁移策略的多层次多粒度并行方案,并基于该方案对所提出的算法进行了并行化.将所提算法应用于多个基准优化问题,实验结果表明,相比于NSGA-II,所提串行算法能够产生收敛性、多样性更为优越的帕累托最优解集,并行算法可在大规模缩短问题求解时间的同时,进一步提升帕累托前沿近似精度. 展开更多
关键词 多目标优化 目标空间分解 Dividing Rectangles算法 并行计算 全局优化
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New sigma point filtering algorithms for nonlinear stochastic systems with correlated noises 被引量:2
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作者 王小旭 潘泉 +1 位作者 程咏梅 赵春晖 《Journal of Central South University》 SCIE EI CAS 2012年第4期1010-1020,共11页
New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated no... New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated noises. Based on the minimum mean square error estimation theory, the nonlinear optimal predictive and correction recursive formulas under the hypothesis that the input noise is correlated with the measurement noise are derived and can be described in a unified framework. Then, UKF and DDF with correlated noises are proposed on the basis of approximation of the posterior mean and covariance in the unified framework by using unscented transformation and second order Stirling's interpolation. The proposed UKF and DDF with correlated noises break through the limitation that input noise and measurement noise must be assumed to be uneorrelated in standard UKF and DDF. Two simulation examples show the effectiveness and feasibility of new algorithms for dealing with nonlinear filtering issue with correlated noises. 展开更多
关键词 nonlinear system correlated noise sigma point unscented Kalman filter divided difference filter
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GEOMORPHOLOGICAL STRUCTURE OF KARST DRAINAGE BASIN AND THE EFFECT ON HYDROLOGY
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作者 Yang Mingde Liang HongGuizhou Horaal University,China 《中国岩溶》 CAS CSCD 北大核心 1992年第S1期84-86,共3页
From the viewpoint of system approach, karst drainage basin is the ideel unit in studying structure and evolutional regularity of karst hydrogeomorpholegical system, It is because the drainage basin is a natural unit ... From the viewpoint of system approach, karst drainage basin is the ideel unit in studying structure and evolutional regularity of karst hydrogeomorpholegical system, It is because the drainage basin is a natural unit with clear border which can reflect the internal structure and outside environment of the system and their interrelation. Through the research on karst hydrology and geomorphology, four basic characteristics of the karst drainage basin have been identified. 展开更多
关键词 KARST drainage REGULARITY BORDER CHARA HYDROLOGY viewpoint chang outside divide
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STUDY ON MULTI-RANGE FRACTALS IN FRACTURED SURFACE OF ROCK
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作者 Zhitie Zhang Zheng Xia 《Journal of Central South University》 SCIE EI CAS 1999年第1期49-51,共3页
Some profile of a rock section and some isopleth of a fractured surface of the rock were divided each into three parts. Then three parts were measured by dividers method and lattice method. It was discovered that the... Some profile of a rock section and some isopleth of a fractured surface of the rock were divided each into three parts. Then three parts were measured by dividers method and lattice method. It was discovered that the fractal dimensions of the three parts were remarkably different, so the fractured surface of rock was not simple fractal but multi range fractals. 展开更多
关键词 FRACTAL multi range fractals SURFACE of ROCK dividers METHOD LATTICE METHOD
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QoS-oriented service composition based on mapping relation tree
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作者 张英 刘晓明 +1 位作者 王智学 陈立 《Journal of Central South University》 SCIE EI CAS 2012年第8期2194-2202,共9页
Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service compo... Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service composition efficiently. Firstly, service descriptions were transformed to mapping relations which denote the association between input and output concepts. Then, the service composition problems were resolved by building mapping relation tree dynamically based on the divide and conquer method, and all mapping relation trees were combined without redundant branch to obtain the composition scheme. Finally, the optimal composition scheme was chosen based on quality of service attributes including the preference of service request. Experiment results illustrate that this method can improve the composition efficiency and reduce the searching time by increasing the number of services in repository. 展开更多
关键词 service composition quality of service mapping relation tree divide and conquer
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Gene transfer and therapy with adenoviral vector in rats with diethylnitrosamine-induced hepatocellular carcinoma 被引量:13
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作者 Miguel Idoate Roberto Bilbao +3 位作者 Bruno Sangro Oscar Bruna Jesus Vazquez Jesus Prieto 《中国实验血液学杂志》 CAS CSCD 1997年第3期301-302,共2页
Viral-mediated gene transfer of thymidine kinase ofherpes simplex virus (HSV-tk) has been used to confercytotoxic sensitivity to ganciclovir (GCV) in a variety oftnmor cells. HSV-tk converts GCV into a phosphorylatedc... Viral-mediated gene transfer of thymidine kinase ofherpes simplex virus (HSV-tk) has been used to confercytotoxic sensitivity to ganciclovir (GCV) in a variety oftnmor cells. HSV-tk converts GCV into a phosphorylatedcompound which is toxic for dividing cells by blockingDNA synthesis. Our previous study has shown 展开更多
关键词 THYMIDINE simplex NODULES cytotoxic adenovirus NUDE dividing inhibit ORTHOTOPIC affects
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Infinitesimal dividing modeling method for dual suppliers inventory model with random lead times 被引量:2
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作者 Ji Pengcheng Song Shiji Wu Cheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期527-536,共10页
As one of the basic inventory cost models, the (Q, τ)inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of "effective lead time" and "lead time de... As one of the basic inventory cost models, the (Q, τ)inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of "effective lead time" and "lead time demand", which may lead to an imprecise inventory cost. Through the real-time statistic of the inventory quantities, this paper considers the precise (Q, τ) inventory cost model of dual supplier procurement by using an infinitesimal dividing method. The traditional modeling method of the inventory cost for dual supplier procurement includes complex procedures. To reduce the complexity effectively, the presented method investigates the statistics properties in real-time of the inventory quantities with the application of the infinitesimal dividing method. It is proved that the optimal holding and shortage costs of dual supplier procurement are less than those of single supplier procurement respectively. With the assumption that both suppliers have the same distribution of lead times, the convexity of the cost function per unit time is proved. So the optimal solution can be easily obtained by applying the classical convex optimization methods. The numerical examples are given to verify the main conclusions. 展开更多
关键词 INVENTORY precise model random lead times dual supplier infinitesimal dividing method optimiza- tion.
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Fast image retargeting based on strip dividing and resizing
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作者 Shungang Hua Honglei Wei Tieming Su 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1072-1081,共10页
Based on image strip dividing, an effective and fast image retargeting algorithm is proposed for resizing images. First,we construct the image energy map using gradient magnitude of the pixels and calculate the accumu... Based on image strip dividing, an effective and fast image retargeting algorithm is proposed for resizing images. First,we construct the image energy map using gradient magnitude of the pixels and calculate the accumulated energy of each column,dividing the image into several strips by integrating similar energy columns. The reduced amount of dimension is decided in inverse proportion to the average energy for each strip. Then we retarget the image combining scaling with cropping in terms of each strip's reduced ratio. Experiment results show that the proposed algorithm is capable of implementing fast image retargeting and preserving both the local structures and the global visual effect of the image. 展开更多
关键词 image retargeting strip dividing energy map SCALING CROPPING
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WORLD NEWS IN BRIEF
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《国际展望》 北大核心 1993年第12期32-32,共1页
(June 1-15, 1993) On June 5, the United Nations Environmental Programme held meeting at the Great Hall of the People in Beijing marking the 21st World Environment Day. Over 500 people from across the country and from ... (June 1-15, 1993) On June 5, the United Nations Environmental Programme held meeting at the Great Hall of the People in Beijing marking the 21st World Environment Day. Over 500 people from across the country and from UNEP and other international organizations participated the commemorative conference. 展开更多
关键词 MARKING NEWS UNEP Premier WITHDRAWAL dividing tentative DRAFT hopes trying
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New judging model of fuzzy cluster optimal dividing based on rough sets theory
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作者 Wang Yun Liu Qinghong +1 位作者 Mu Yong Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期392-397,共6页
To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totali... To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totality sample space, two algorithms are proposed on the basis of the data analysis method in rough sets theory: information system discrete algorithm (algorithm 1) and samples representatives judging algorithm (algorithm 2). On the principle of the farthest distance, algorithm 1 transforms continuous data into discrete form which could be transacted by rough sets theory. Taking the approximate precision as a criterion, algorithm 2 chooses the sample space with a good representative. Hence, the clustering sample set in inducing and computing optimal dividing matrix can be achieved. Several theorems are proposed to provide strict theoretic foundations for the execution of the algorithm model. An applied example based on the new algorithm model is given, whose result verifies the feasibility of this new algorithm model. 展开更多
关键词 Rough sets theory Fuzzy optimal dividing matrix Representatives of samples Fuzzy cluster analysis Information system approximate precision.
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