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A Sharding Scheme Based on Graph Partitioning Algorithm for Public Blockchain
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作者 Shujiang Xu Ziye Wang +4 位作者 Lianhai Wang Miodrag J.Mihaljevi′c Shuhui Zhang Wei Shao Qizheng Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3311-3327,共17页
Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business processes.However,tra... Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business processes.However,transaction performance and scalability has become the main challenges hindering the widespread adoption of blockchain.Due to its inability to meet the demands of high-frequency trading,blockchain cannot be adopted in many scenarios.To improve the transaction capacity,researchers have proposed some on-chain scaling technologies,including lightning networks,directed acyclic graph technology,state channels,and shardingmechanisms,inwhich sharding emerges as a potential scaling technology.Nevertheless,excessive cross-shard transactions and uneven shard workloads prevent the sharding mechanism from achieving the expected aim.This paper proposes a graphbased sharding scheme for public blockchain to efficiently balance the transaction distribution.Bymitigating crossshard transactions and evening-out workloads among shards,the scheme reduces transaction confirmation latency and enhances the transaction capacity of the blockchain.Therefore,the scheme can achieve a high-frequency transaction as well as a better blockchain scalability.Experiments results show that the scheme effectively reduces the cross-shard transaction ratio to a range of 35%-56%and significantly decreases the transaction confirmation latency to 6 s in a blockchain with no more than 25 shards. 展开更多
关键词 Blockchain sharding graph partitioning algorithm
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A semi-implicit partition algorithm for fluid-structure coupling problems based on modal force prediction-correction
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作者 Kangdi LI Zili XU +2 位作者 Shizhi ZHAO Lu CHENG Yu FANG 《Chinese Journal of Aeronautics》 2025年第5期275-286,共12页
The implicit partition algorithm used to solve fluid–structure coupling problems has high accuracy,but it requires a long computation time.In this paper,a semi-implicit fluid–structure coupling algorithm based on mo... The implicit partition algorithm used to solve fluid–structure coupling problems has high accuracy,but it requires a long computation time.In this paper,a semi-implicit fluid–structure coupling algorithm based on modal force prediction-correction is proposed to improve the computational efficiency.In the pre-processing stage,the fluid domain is assumed to be a pseudo-elastic solid and merged with the solid domain to form a holistic system,and the normalized modal information of the holistic system is calculated and stored.During the sub-step cycle,the modal superposition method is used to obtain the response of the holistic system with the predicted modal force as the load,so that the deformation of the structure and the updating of the fluid mesh can be achieved simultaneously.After solving the Reynolds-averaged Navier-Stokes equations in the fluid domain,the predicted modal force is corrected and a new sub-step cycle is started until the converged result is obtained.In this method,the computation of the fluid equations and the updating of the dynamic mesh are done implicitly,while the deformation of the structure is done explicitly.Two numerical cases,vortex induced oscillation of an elastic beam and fluid–structure interaction of a final stage blade,are used to verify the efficiency and accuracy of the proposed algorithm.The results show that the proposed method achieves the same accuracy as the implicit method while the computational time is reduced.In the case of the vortex-induced oscillation problem,the computational time can be reduced to 18.6%.In the case of the final stage blade vibration,the computational time can be reduced to 53.8%. 展开更多
关键词 Fluid-structure interaction Fast mesh deformation Semi-implicit partition algorithm Prediction-correction method FLUTTER
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Three stage dynamic partitioning method of active distribution network based on improved sand cat swarm
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作者 ZHANG Maosong ZHANG Luyao +3 位作者 YANG Jie YANG Lingxiao WANG Xiuqin TAO Jun 《High Technology Letters》 2025年第3期211-225,共15页
With the large-scale integration of renewable energy sources into the grid,distribution networks are increasingly challenged by issues related to renewable energy accommodation and the mainte-nance of power quality st... With the large-scale integration of renewable energy sources into the grid,distribution networks are increasingly challenged by issues related to renewable energy accommodation and the mainte-nance of power quality stability.To address the challenge that existing partitioning methods are inad-equate for the planning and operation needs of active distribution networks under frequently changing power flow conditions,a three-stage dynamic partitioning approach is proposed based on an im-proved sand cat swarm optimization(ISCSO)algorithm.Firstly,a comprehensive dynamic partitio-ning index is developed by integrating both structural and functional metrics,including modularity,voltage regulation capability,and regional renewable energy accommodation capacity.Secondly,to overcome the limitations of the conventional sand cat swarm optimization,namely its weak global ex-ploration ability and tendency to fall into local optima in the later optimization stages,chaotic map-ping is employed to initialize a uniformly distributed population.A nonlinear sensitivity mechanism is introduced to balance global exploration and local exploitation,alongside the design of a particle encoding and position updating scheme tailored for dynamic partitioning.Furthermore,a‘state re-tention-local adjustment-global reconstruction’partitioning structure is developed.To avoid unnec-essary partition changes under minor source-load fluctuations,the concept of overlapping nodes is introduced,enabling fine-tuned adjustments under such conditions.Finally,two experimental sce-narios are designed to validate the proposed method.Simulation results demonstrate strong electrical coupling performance and show that the method enhances voltage regulation and renewable energy integration capabilities across regions. 展开更多
关键词 renewable energy consumption dynamic partition MODULARITY voltage regulation sand cat swarm algorithm overlapping nodes
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Fingerprint Directional Image Partitioning Based on Genetic Algorithm
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作者 张朝鸣 刘云超 《Advances in Manufacturing》 SCIE CAS 2000年第S1期98-103,共6页
In this work, we introduce a method of fingerprint directional image partitioning based on GA. According to the fingerprint topology, A set of dynamic partition masks and a cost estimating function are designed to gui... In this work, we introduce a method of fingerprint directional image partitioning based on GA. According to the fingerprint topology, A set of dynamic partition masks and a cost estimating function are designed to guide the partitioning procedure. Finding best fitted mask application is converted to an functional optimizing problem, and we give out a GA solution to the problem. At last, we discuss the application of the proposed method in Fingerprint Classification. 展开更多
关键词 fingerprint classification directional image partitioning dynamic mask cost estimating function genetic algorithm (GA)
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Research on Petri Net System Parallel Subnet Partitioning Completeness Theory and Algorithm 被引量:1
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作者 LI Wenjing LI Songzhao LU Jianbo 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第3期205-217,共13页
In order to solve the parallel algorithm of Petri net system with concurrent function, so as to achieve the parallel control and simulation operation of this system, this paper proposes the function partition complete... In order to solve the parallel algorithm of Petri net system with concurrent function, so as to achieve the parallel control and simulation operation of this system, this paper proposes the function partition completeness theory and algorithms of Petri net parallelization, thereby providing the theoretical support for the realization of Petri parallel algorithms. Firstly, according to the concurrent characteristics of Petri net model, we analyze the parallelism of Petri net system; then, by giving the solving process of place invariants and the function partitioning of Petri net, we propose the function partitioning conditions and determination theorem of Petri net parallelization, and conduct its theoretical proof and practical verification. On this basis, we conduct the theoretical study and analysis on the situation that Petri net system has several kinds of parallel function partitioning, propose the completeness theorem of parallelism function partitioning in Petri net system, and verify it. Finally, we give the algorithms, application examples and simulation experiment results of parallel function partitioning of Petri net systems based on place invariant. The theoretical proof and experimental results show that the function partitioning conditions and completeness theory of Petri net parallelization based on place invariant are correct, and the parallel algorithms under such theoretical basis are also correct and effective. 展开更多
关键词 PETRI NET PARALLELIZATION partitioning conditions COMPLETENESS partitioning algorithm
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Task Graph Reduction Algorithm for Hardware/Software Partitioning 被引量:2
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作者 LI Hui LIU Wenjui +2 位作者 WU Jigang JIANG Guiyuan HAN Honglei 《Wuhan University Journal of Natural Sciences》 CAS 2012年第2期126-130,共5页
Hardware/software(HW/SW) partitioning is one of the key processes in an embedded system.It is used to determine which system components are assigned to hardware and which are processed by software.In contrast with p... Hardware/software(HW/SW) partitioning is one of the key processes in an embedded system.It is used to determine which system components are assigned to hardware and which are processed by software.In contrast with previous research that focuses on developing efficient heuristic,we focus on the pre-process of the task graph before the HW/SW partitioning in this paper,that is,enumerating all the sub-graphs that meet the requirements.Experimental results showed that the original graph can be reduced to 67% in the worst-case scenario and 58% in the best-case scenario.In conclusion,the reduced task graph saved hardware area while improving partitioning speed and accuracy. 展开更多
关键词 HW/SW partitioning task graph algorithm embedded system
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Multi-objective Evolutionary Algorithm Based on Target Space Partitioning Method
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作者 尚兆霞 刘弘 李焱 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期177-181,共5页
Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimizatio... Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimization problem, thus achieve the coherent solution which can meet the requirements of all target functions, and improve the population's overall evolution level. The algorithm which guarantees diversity preservation and fast convergence to the Pareto set is applied to structural optimization problems. The empirical analysis supports the algorithm and gives an example with program. 展开更多
关键词 OPTIMIZATION algorithm MULTI-OBJECTIVE TARGET SPACE partitioning METHOD
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Hardware/software partitioning based on dynamic combination of maximum entropy and chaos optimization algorithm
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作者 张宏烈 张国印 姚爱红 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第4期548-551,共4页
This paper presents an algorithm that combines the chaos optimization algorithm with the maximum entropy ( COA-ME) by using entropy model based on chaos algorithm,in which the maximum entropy is used as the second met... This paper presents an algorithm that combines the chaos optimization algorithm with the maximum entropy ( COA-ME) by using entropy model based on chaos algorithm,in which the maximum entropy is used as the second method of searching the excellent solution. The search direction is improved by chaos optimization algorithm and realizes the selective acceptance of wrong solution. The experimental result shows that the presented algorithm can be used in the partitioning of hardware/software of reconfigurable system. It effectively reduces the local extremum problem,and search speed as well as performance of partitioning is improved. 展开更多
关键词 hardware/software partitioning CHAOS optimization algorithm MAXIMUM ENTROPY RECONFIGURABLE system
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Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method)–Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm
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作者 Zoran Gligoric Milos Gligoric +2 位作者 Igor Miljanovic Suzana Lutovac Aleksandar Milutinovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期955-979,共25页
Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very impor... Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems.Three methods are commonly used for assessing the weights of criteria:objective,subjective,and integrated methods.In this study,an objective approach is proposed to assess the weights of criteria,called SPCmethod(Symmetry Point of Criterion).This point enriches the criterion so that it is balanced and easy to implement in the process of the evaluation of its influence on decision-making.The SPC methodology is systematically presented and supported by detailed calculations related to an artificial example.To validate the developed method,we used our numerical example and calculated the weights of criteria by CRITIC,Entropy,Standard Deviation and MEREC methods.Comparative analysis between these methods and the SPC method reveals that the developedmethod is a very reliable objective way to determine the weights of criteria.Additionally,in this study,we proposed the application of SPCmethod to evaluate the efficiency of themulti-criteria partitioning algorithm.The main idea of the evaluation is based on the following fact:the greater the uniformity of the weights of criteria,the higher the efficiency of the partitioning algorithm.The research demonstrates that the SPC method can be applied to solving different multi-criteria problems. 展开更多
关键词 Multi-criteria decision-making weights of criteria symmetry point of criterion mineral deposit partitioning algorithm performance evaluation
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Algorithm Selection Method Based on Coupling Strength for Partitioned Analysis of Structure-Piezoelectric-Circuit Coupling
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作者 Daisuke Ishihara Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1237-1258,共22页
In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct pi... In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct piezoelectriccoupling and direct piezoelectric and circuit coupling. In the proposed method, implicit and explicit formulationsare used for strong and weak coupling, respectively. Three feasible partitioned algorithms are generated, namely(1) a strongly coupled algorithm that uses a fully implicit formulation for both types of coupling, (2) a weaklycoupled algorithm that uses a fully explicit formulation for both types of coupling, and (3) a partially stronglycoupled and partially weakly coupled algorithm that uses an implicit formulation and an explicit formulation forthe two types of coupling, respectively.Numerical examples using a piezoelectric energy harvester,which is a typicalstructure-piezoelectric-circuit coupling problem, demonstrate that the proposed method selects the most costeffectivealgorithm. 展开更多
关键词 MULTIPHYSICS coupling strength partitioned algorithm structure-piezoelectric-circuit coupling strongly coupled algorithm weakly coupled algorithm
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基于动态区域划分的配电网台区三相不平衡治理策略
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作者 陈晓龙 徐颖 李斌 《电力自动化设备》 北大核心 2025年第8期208-216,共9页
传统三相不平衡治理仅关注变压器关口处的三相不平衡情况,忽略了台区内部不平衡特征,且多采用静态调相策略,难以适应灵活源荷接入下低压配电网运行状态的动态变化。为此,提出了一种基于动态区域划分的三相不平衡治理策略。提出基于分区... 传统三相不平衡治理仅关注变压器关口处的三相不平衡情况,忽略了台区内部不平衡特征,且多采用静态调相策略,难以适应灵活源荷接入下低压配电网运行状态的动态变化。为此,提出了一种基于动态区域划分的三相不平衡治理策略。提出基于分区评价指数与阈值触发机制的动态分区方法,以划定后续相序优化的区域范围。建立考虑多类型灵活调节资源的双层优化模型,上层以各分区三相不平衡度最小为目标优化相序配置,下层构建以运行成本最小为目标的电压优化模型。采用基于云模型改进的遗传算法和Gurobi求解器分别求解上下层模型。基于改进的IEEE 123节点系统和0.38 kV实际配电网台区进行仿真,验证了所提策略的有效性与优越性。 展开更多
关键词 配电网 三相不平衡 动态分区 双层优化模型 相序优化 云模型 遗传算法
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基于动态分区与收敛速度控制器的改进竞争群优化算法
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作者 张伟 伊杰昌 《控制与决策》 北大核心 2025年第10期3019-3028,共10页
为提升竞争群优化(CSO)算法在解决复杂高维优化问题时的性能,提出一种基于分区策略与收敛速度控制器的改进竞争群优化(PCSCCSO)算法.首先,采用适应度变化率驱动的动态分区策略,以增强算法的收敛性和搜索效率;然后,提出一种快速CSO策略,... 为提升竞争群优化(CSO)算法在解决复杂高维优化问题时的性能,提出一种基于分区策略与收敛速度控制器的改进竞争群优化(PCSCCSO)算法.首先,采用适应度变化率驱动的动态分区策略,以增强算法的收敛性和搜索效率;然后,提出一种快速CSO策略,通过三重竞争机制增强算法的寻优能力:获胜粒子通过对立学习策略更新,失败粒子向获胜子群平均位置学习,劣败粒子通过变异增强局部搜索,这些策略能够有效平衡全局探索与局部开发,提高算法的寻优效率;最后,结合粒子与全局最优解间的余弦相似度以及停滞计数,设计自适应的收敛速度控制器,用以调节粒子的搜索行为,从而避免粒子陷入局部最优解,加速全局收敛.理论分析验证了所提出算法的稳定性和收敛性.实验结果表明,与其他改进算法相比,PCSCCSO算法在处理复杂高维优化问题时具有更好的收敛精度和收敛效率. 展开更多
关键词 竞争群优化算法 高维优化 种群分区 三重竞争 快速CSO策略 收敛速度控制器
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CONSTRAINED VITERBI ALGORITHM AND ITS APPLICATION TO ERROR RESILIENT TRANSMISSION OF SPIHT CODED IMAGES 被引量:1
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作者 周霆 许明 +1 位作者 陈东侠 余轮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期155-159,共5页
To overcome some drawbacks of Viterbi algorithm (VA), such as exponential growing complexity of decoding, and its poor performance under bad channel conditions, some available known information must be used as cons... To overcome some drawbacks of Viterbi algorithm (VA), such as exponential growing complexity of decoding, and its poor performance under bad channel conditions, some available known information must be used as constrained condition and apriori knowledge for decoding. A new constrained VA is proposed by adding con- straint bits directly for conventional codec. Compared with the conventional VA, under the bad channel condi- tion, the proposed scheme can improve the peak signal to noise ratio (PSNR) of the decoding image 2--10 dB by changing the number of constrained bits. Experimental results show that it is an efficient error-controlling way for the transmission of set partitioning in hierarchical trees (SPIHT) coded image. 展开更多
关键词 Viterbi algorithm(VA) image communication systems constrained Viterbi algorithm(C-VA) set partitioning in hierachical trees(SPIHT)
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基于任务均衡的双臂三维激光切割机分区算法研究与验证
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作者 王靖 舒雷 +1 位作者 林毓培 段书凯 《西南大学学报(自然科学版)》 北大核心 2025年第6期213-223,共11页
为了提高多切割头三维激光切割机的协同切割效率,提出了一种新的任务均衡分区算法。该算法在路径规划前对切割任务进行了预分区,预分区时综合考虑了待切孔大小和切割辅助耗时等因素,增强了分区的可靠性,在路径规划后依据耗时差值最小的... 为了提高多切割头三维激光切割机的协同切割效率,提出了一种新的任务均衡分区算法。该算法在路径规划前对切割任务进行了预分区,预分区时综合考虑了待切孔大小和切割辅助耗时等因素,增强了分区的可靠性,在路径规划后依据耗时差值最小的原则调整分区,实现了两分区耗时平衡和交错距离最小化。在采用遗传算法的路径规划中引入了位置约束,降低了切割头碰撞风险。将其与模糊C聚类法和KMeans聚类法共同应用于模拟的三维零件和实际生产的汽车车身零件的分区以及路径规划试验中,并以空行程长度、切割耗时和分区间隙为指标对比探究其优劣。结果表明:针对模拟的三维零件,任务均衡法在耗时差值和分区间隙方面均优于聚类法,在空行程长度方面较聚类法稳定性更好;针对实际生产的B柱零件,3种任务分区算法结果完全一致,效果均很好;针对实际生产的车门内板零件,任务均衡法在空行程方面优于聚类法,在耗时差值、最大耗时和分区间隙方面的优势更加明显。 展开更多
关键词 任务均衡 三维激光切割 分区算法 协同 路径规划
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非一致性极值降雨空间聚类和频率及对气候因子响应研究
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作者 曾杭 周洋 +2 位作者 李建柱 杨琦 黄佳期 《水力发电学报》 北大核心 2025年第6期72-88,共17页
随着全球气候变化影响,极值降雨序列的空间聚类演变和气候响应特征对流域暴雨风险估计有非常重要的意义。本文以湘江流域为研究区域,采用基于变差函数F-madogram的围绕中心点划分(PAM)聚类算法将流域极值降雨序列分为3个聚类分区;筛选... 随着全球气候变化影响,极值降雨序列的空间聚类演变和气候响应特征对流域暴雨风险估计有非常重要的意义。本文以湘江流域为研究区域,采用基于变差函数F-madogram的围绕中心点划分(PAM)聚类算法将流域极值降雨序列分为3个聚类分区;筛选出与各聚类分区大部分站点相关性显著的气候驱动因子,以各聚类中心站点为代表,构建基于贝叶斯的非一致性极值降雨频率计算模型。结果表明:极值聚类算法相较K均值聚类法更适用于极值降雨序列;以气候因子为协变量的时变矩模型表现最优,且其不确定性区间最小;当前一年北大西洋涛动为负相、同年西太平洋海面气压升高和东太平洋海面温度上升时,湘江流域上中下游夏季极值降雨频率增加,为湘江流域极值暴雨风险估计和预测提供科学依据。 展开更多
关键词 极值空间聚类 变差函数 围绕中心点划分聚类算法 气候驱动 非一致性极值降雨 湘江流域
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求解大规模图划分问题的混合遗传算法 被引量:2
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作者 曹欢欢 刘红卫 路文军 《吉林大学学报(理学版)》 北大核心 2025年第3期822-828,共7页
针对大规模图划分问题中划分方案数量随顶点数指数级增长而导致的计算复杂性,以及传统遗传算法在处理大规模问题时效率和精度不足的问题,提出一种混合遗传算法.首先,该算法对经过二进制编码的个体进行最佳匹配,通过识别并筛选出优良基因... 针对大规模图划分问题中划分方案数量随顶点数指数级增长而导致的计算复杂性,以及传统遗传算法在处理大规模问题时效率和精度不足的问题,提出一种混合遗传算法.首先,该算法对经过二进制编码的个体进行最佳匹配,通过识别并筛选出优良基因,有效缩小搜索范围,聚焦于更具潜力的搜索区域;其次,为避免传统交叉操作可能产生的非法解,该算法摒弃了随机交叉策略,仅生成一个潜在解;最后,在变异操作中引入禁忌搜索算子,生成完整的个体,从而增强算法的局部搜索能力,实现全局搜索与局部搜索之间的动态平衡.将该混合遗传算法应用于超大规模集成电路划分问题的实验结果表明,该算法可有效改进大规模图二划分问题解的质量. 展开更多
关键词 图划分 遗传算法 最佳匹配 优良基因 禁忌搜索
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基于GN-NSGA-Ⅲ算法的供水管网DMA分区设计
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作者 石可铨 李红艳 +2 位作者 张峰 常子峰 毛立波 《给水排水》 北大核心 2025年第8期153-158,164,共7页
针对现有供水管网分区优化算法存在分区效果差和决策方案滞后等问题,提出了一种基于GN和NSGA-Ⅲ算法的供水管网DMA分区方法。将管道的管径、管长、流量和高程差构建边权比,利用GN算法完成对DMA区域的划分,得到模块度最大的分区结果。优... 针对现有供水管网分区优化算法存在分区效果差和决策方案滞后等问题,提出了一种基于GN和NSGA-Ⅲ算法的供水管网DMA分区方法。将管道的管径、管长、流量和高程差构建边权比,利用GN算法完成对DMA区域的划分,得到模块度最大的分区结果。优先压力满足后,经过二级分区,以管网的节点平均压力、改造费用、节点流量加权平均水龄和模块度为优化目标,使用NSGA-Ⅲ算法优化设计阀门和流量计位置,结合优劣解距离法筛选最终方案。将该方法应用于山西省孝义市管网,通过压力管理,管网平均压力和节点流量加权平均水龄分别降低了2.27 mH_(2)O和0.017 h筛选出降压幅度大、水质条件优和改造费用低的分区方案,具有良好的经济和现实意义。 展开更多
关键词 Girvan-Newman算法 管网DMA分区 优劣解距离法 NSGA-Ⅲ算法
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化学反应器网络自动生成方法在微混燃烧室中的应用
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作者 帅佳玮 雷福林 张哲巅 《热力发电》 北大核心 2025年第9期125-134,共10页
计算流体力学-化学反应器网络(computational fluid dynamics-chemical reactor network,CFD-CRN)模拟是一种适合燃气轮机NO_(x)排放预测的方法,基于此方法开发了具有通用性的CRN自动分区/求解程序,并在天然气微混燃烧室上进行应用与验... 计算流体力学-化学反应器网络(computational fluid dynamics-chemical reactor network,CFD-CRN)模拟是一种适合燃气轮机NO_(x)排放预测的方法,基于此方法开发了具有通用性的CRN自动分区/求解程序,并在天然气微混燃烧室上进行应用与验证。通过CFD软件模拟分析微混燃烧室的流动和燃烧特性,建立CRN分区准则:首先将空气区和燃料区提取出来,然后沿轴向主分区,再根据燃料分级沿径向/周向细分区域。结果表明,CRN自动分区/求解程序使用可扩展标记语言XML(extensible markup language)规范化信息接口增强了通用性,适用于复杂燃烧室结构,对微混燃烧室不同工况的NO_(x)排放预测值与实验值相对误差小于11%,并且CFD网格数对CRN预测NO_(x)排放值的影响较小;同时分析了燃料分配比例对微混燃烧室NO_(x)排放的影响,给出了合适的调节范围。该CRN自动分区/求解算法在燃气轮机NO_(x)排放预测方面具有应用潜力。 展开更多
关键词 微混燃烧室 化学反应器网络 CRN分区算法 燃料分级 NO_(x)排放
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含分布式电源配电网的两阶段电压控制分区方法
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作者 杨爱纲 杨淼然 +1 位作者 谢立君 邵建伟 《电力工程技术》 北大核心 2025年第3期219-227,共9页
针对含分布式电源配电网中数据量大,以及传统基于复杂网络理论的电网分区方法存在分区不合理、区域内部无功调节能力不足等问题,文中提出一种基于复杂网络理论的两阶段分区方法。第一阶段基于映射分区的思想,依据“最小电气距离”原则... 针对含分布式电源配电网中数据量大,以及传统基于复杂网络理论的电网分区方法存在分区不合理、区域内部无功调节能力不足等问题,文中提出一种基于复杂网络理论的两阶段分区方法。第一阶段基于映射分区的思想,依据“最小电气距离”原则对负荷节点进行初始分区,使得无功源能够更好地协调和控制区内负荷节点,同时减小第二阶段的初始社团规模。第二阶段利用Louvain社团发现算法进行分区凝聚,通过改进分区模块度函数对初始分区进行调整,保证分区的无功调节能力。以IEEE 69节点系统为例验证文中所提方法的有效性。采用该方法分区后的分区数量、区域间无功转移量相较传统方法均有所减小,结果表明文中所提分区方法的无功调节能力更强,更适用于配电网的区域电压无功自治控制。 展开更多
关键词 分布式电源 复杂网络理论 无功电压分区 负荷节点 映射分区 Louvain算法
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初级分裂式永磁直线电机的多目标优化 被引量:1
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作者 徐振宇 程洪 +2 位作者 苏金泽 李春雨 程远雄 《微特电机》 2025年第2期7-13,19,共8页
提出了一种初级分裂式永磁直线直驱运动单元结构,其电机运用磁调制原理,可以增大电机推力密度,其永磁体与电枢为整体结构且两者分区布置,能够降低永磁体用量并提供更好的散热条件,适合长行程应用。研究了提升电磁推力的电磁结构设计方法... 提出了一种初级分裂式永磁直线直驱运动单元结构,其电机运用磁调制原理,可以增大电机推力密度,其永磁体与电枢为整体结构且两者分区布置,能够降低永磁体用量并提供更好的散热条件,适合长行程应用。研究了提升电磁推力的电磁结构设计方法,采用电磁场有限元方法计算了磁阻推力,分析了提高磁阻推力和抑制波动的电磁结构影响因素,结果表明,初级分裂结构能有效提高电机的推力水平。针对电磁结构参数复杂、性能目标多的问题,利用有限元计算方法建立了电机的BP神经网络代理模型,并使用NSGA-Ⅱ智能优化算法进行多目标优化,优化后电机推力提升13.93%,电机推力波动降低13.89%。该分裂式电机在直线直驱运动单元领域具有重要的应用潜力。 展开更多
关键词 初级分裂式永磁直线电机 BP神经网络 NSGA-Ⅱ智能算法 电磁场有限元
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