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Smart Bubble Sort:A Novel and Dynamic Variant of Bubble Sort Algorithm
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作者 Mohammad Khalid Imam Rahmani 《Computers, Materials & Continua》 SCIE EI 2022年第6期4895-4913,共19页
In the present era,a very huge volume of data is being stored in online and offline databases.Enterprise houses,research,medical as well as healthcare organizations,and academic institutions store data in databases an... In the present era,a very huge volume of data is being stored in online and offline databases.Enterprise houses,research,medical as well as healthcare organizations,and academic institutions store data in databases and their subsequent retrievals are performed for further processing.Finding the required data from a given database within the minimum possible time is one of the key factors in achieving the best possible performance of any computer-based application.If the data is already sorted,finding or searching is comparatively faster.In real-life scenarios,the data collected from different sources may not be in sorted order.Sorting algorithms are required to arrange the data in some order in the least possible time.In this paper,I propose an intelligent approach towards designing a smart variant of the bubble sort algorithm.I call it Smart Bubble sort that exhibits dynamic footprint:The capability of adapting itself from the average-case to the best-case scenario.It is an in-place sorting algorithm and its best-case time complexity isΩ(n).It is linear and better than bubble sort,selection sort,and merge sort.In averagecase and worst-case analyses,the complexity estimates are based on its static footprint analyses.Its complexity in worst-case is O(n2)and in average-case isΘ(n^(2)).Smart Bubble sort is capable of adapting itself to the best-case scenario from the average-case scenario at any subsequent stages due to its dynamic and intelligent nature.The Smart Bubble sort outperforms bubble sort,selection sort,and merge sort in the best-case scenario whereas it outperforms bubble sort in the average-case scenario. 展开更多
关键词 sorting algorithms smart bubble sort FOOTPRINT dynamic footprint time complexity asymptotic analysis
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Improving path planning efficiency for underwater gravity-aided navigation based on a new depth sorting fast search algorithm
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作者 Xiaocong Zhou Wei Zheng +2 位作者 Zhaowei Li Panlong Wu Yongjin Sun 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期285-296,共12页
This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapi... This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results. 展开更多
关键词 Depth sorting Fast Search algorithm Underwater gravity-aided navigation Path planning efficiency Quick Rapidly-exploring Random Trees*(QRRT*)
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Accelerating Large-Scale Sorting through Parallel Algorithms
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作者 Yahya Alhabboub Fares Almutairi +3 位作者 Mohammed Safhi Yazan Alqahtani Adam Almeedani Yasir Alguwaifli 《Journal of Computer and Communications》 2024年第1期131-138,共8页
This study explores the application of parallel algorithms to enhance large-scale sorting, focusing on the QuickSort method. Implemented in both sequential and parallel forms, the paper provides a detailed comparison ... This study explores the application of parallel algorithms to enhance large-scale sorting, focusing on the QuickSort method. Implemented in both sequential and parallel forms, the paper provides a detailed comparison of their performance. This study investigates the efficacy of both techniques through the lens of array generation and pivot selection to manage datasets of varying sizes. This study meticulously documents the performance metrics, recording 16,499.2 milliseconds for the serial implementation and 16,339 milliseconds for the parallel implementation when sorting an array by using C++ chrono library. These results suggest that while the performance gains of the parallel approach over its serial counterpart are not immediately pronounced for smaller datasets, the benefits are expected to be more substantial as the dataset size increases. 展开更多
关键词 sorting algorithm Quick sort Quicksort Parallel Parallel algorithms
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A decoupled multi-objective optimization algorithm for cut order planning of multi-color garment
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作者 DONG Hui LYU Jinyang +3 位作者 LIN Wenjie WU Xiang WU Mincheng HUANG Guangpu 《High Technology Letters》 2025年第1期53-62,共10页
This work addresses the cut order planning(COP)problem for multi-color garment production,which is the first step in the clothing industry.First,a multi-objective optimization model of multicolor COP(MCOP)is establish... This work addresses the cut order planning(COP)problem for multi-color garment production,which is the first step in the clothing industry.First,a multi-objective optimization model of multicolor COP(MCOP)is established with production error and production cost as optimization objectives,combined with constraints such as the number of equipment and the number of layers.Second,a decoupled multi-objective optimization algorithm(DMOA)is proposed based on the linear programming decoupling strategy and non-dominated sorting in genetic algorithmsⅡ(NSGAII).The size-combination matrix and the fabric-layer matrix are decoupled to improve the accuracy of the algorithm.Meanwhile,an improved NSGAII algorithm is designed to obtain the optimal Pareto solution to the MCOP problem,thereby constructing a practical intelligent production optimization algorithm.Finally,the effectiveness and superiority of the proposed DMOA are verified through practical cases and comparative experiments,which can effectively optimize the production process for garment enterprises. 展开更多
关键词 multi-objective optimization non-dominated sorting in genetic algorithmsⅡ(NSGAII) cut order planning(COP) multi-color garment linear programming decoupling strategy
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Improvement of Counting Sorting Algorithm
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作者 Chenglong Song Haiming Li 《Journal of Computer and Communications》 2023年第10期12-22,共11页
By analyzing the internal features of counting sorting algorithm. Two improvements of counting sorting algorithms are proposed, which have a wide range of applications and better efficiency than the original counting ... By analyzing the internal features of counting sorting algorithm. Two improvements of counting sorting algorithms are proposed, which have a wide range of applications and better efficiency than the original counting sort while maintaining the original stability. Compared with the original counting sort, it has a wider scope of application and better time and space efficiency. In addition, the accuracy of the above conclusions can be proved by a large amount of experimental data. 展开更多
关键词 sort algorithm Counting sorting algorithms COMPLEXITY Internal Features
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Improved non-dominated sorting genetic algorithm (NSGA)-II in multi-objective optimization studies of wind turbine blades 被引量:28
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作者 王珑 王同光 罗源 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第6期739-748,共10页
The non-dominated sorting genetic algorithm (NSGA) is improved with the controlled elitism and dynamic crowding distance. A novel multi-objective optimization algorithm is obtained for wind turbine blades. As an exa... The non-dominated sorting genetic algorithm (NSGA) is improved with the controlled elitism and dynamic crowding distance. A novel multi-objective optimization algorithm is obtained for wind turbine blades. As an example, a 5 MW wind turbine blade design is presented by taking the maximum power coefficient and the minimum blade mass as the optimization objectives. The optimal results show that this algorithm has good performance in handling the multi-objective optimization of wind turbines, and it gives a Pareto-optimal solution set rather than the optimum solutions to the conventional multi objective optimization problems. The wind turbine blade optimization method presented in this paper provides a new and general algorithm for the multi-objective optimization of wind turbines. 展开更多
关键词 wind turbine multi-objective optimization Pareto-optimal solution non-dominated sorting genetic algorithm (NSGA)-II
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Multi-objective optimization of water supply network rehabilitation with non-dominated sorting Genetic Algorithm-II 被引量:3
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作者 Xi JIN Jie ZHANG +1 位作者 Jin-liang GAO Wen-yan WU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第3期391-400,共10页
Through the transformation of hydraulic constraints into the objective functions associated with a water supply network rehabilitation problem, a non-dominated sorting Genetic Algorithm-II (NSGA-II) can be used to sol... Through the transformation of hydraulic constraints into the objective functions associated with a water supply network rehabilitation problem, a non-dominated sorting Genetic Algorithm-II (NSGA-II) can be used to solve the altered multi-objective optimization model. The introduction of NSGA-II into water supply network optimal rehabilitation problem solves the conflict between one fitness value of standard genetic algorithm (SGA) and multi-objectives of rehabilitation problem. And the uncertainties brought by using weight coefficients or punish functions in conventional methods are controlled. And also by in-troduction of artificial inducement mutation (AIM) operation, the convergence speed of population is accelerated;this operation not only improves the convergence speed, but also improves the rationality and feasibility of solutions. 展开更多
关键词 Water supply system Water supply network Optimal rehabilitation MULTI-OBJECTIVE Non-dominated sorting Ge-netic algorithm (NSGA)
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GREEDY NON-DOMINATED SORTING IN GENETIC ALGORITHM-ⅡFOR VEHICLE ROUTING PROBLEM IN DISTRIBUTION 被引量:4
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作者 WEI Tian FAN Wenhui XU Huayu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第6期18-24,共7页
Vehicle routing problem in distribution (VRPD) is a widely used type of vehicle routing problem (VRP), which has been proved as NP-Hard, and it is usually modeled as single objective optimization problem when mode... Vehicle routing problem in distribution (VRPD) is a widely used type of vehicle routing problem (VRP), which has been proved as NP-Hard, and it is usually modeled as single objective optimization problem when modeling. For multi-objective optimization model, most researches consider two objectives. A multi-objective mathematical model for VRP is proposed, which considers the number of vehicles used, the length of route and the time arrived at each client. Genetic algorithm is one of the most widely used algorithms to solve VRP. As a type of genetic algorithm (GA), non-dominated sorting in genetic algorithm-Ⅱ (NSGA-Ⅱ) also suffers from premature convergence and enclosure competition. In order to avoid these kinds of shortage, a greedy NSGA-Ⅱ (GNSGA-Ⅱ) is proposed for VRP problem. Greedy algorithm is implemented in generating the initial population, cross-over and mutation. All these procedures ensure that NSGA-Ⅱ is prevented from premature convergence and refine the performance of NSGA-Ⅱ at each step. In the distribution problem of a distribution center in Michigan, US, the GNSGA-Ⅱ is compared with NSGA-Ⅱ. As a result, the GNSGA-Ⅱ is the most efficient one and can get the most optimized solution to VRP problem. Also, in GNSGA-Ⅱ, premature convergence is better avoided and search efficiency has been improved sharply. 展开更多
关键词 Greedy non-dominated sorting in genetic algorithm-Ⅱ (GNSGA-Ⅱ) Vehicle routing problem (VRP) Multi-objective optimization
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基于SORT映射的IRCMFDE在旋转机械故障诊断中的应用 被引量:2
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作者 王潞红 邹平吉 《机电工程》 北大核心 2024年第1期11-21,共11页
针对旋转机械振动信号的强非线性和非平稳性,导致故障特征提取困难的问题,提出了一种基于SORT映射的改进精细复合多尺度波动散布熵(IRCMFDE)和蝙蝠算法优化的相关向量机(BA-RVM)的旋转机械故障诊断方法。首先,利用SORT映射函数替换了精... 针对旋转机械振动信号的强非线性和非平稳性,导致故障特征提取困难的问题,提出了一种基于SORT映射的改进精细复合多尺度波动散布熵(IRCMFDE)和蝙蝠算法优化的相关向量机(BA-RVM)的旋转机械故障诊断方法。首先,利用SORT映射函数替换了精细复合多尺度波动散布熵(RCMFDE)方法的正态累积分布函数,同时对RCMFDE方法的粗粒化方式进行了改进,提出了基于SORT映射的IRCMFDE方法;随后,利用IRCMFDE方法提取了旋转机械振动信号的故障特征,构造了故障特征集;最后,采用BA-RVM分类器对旋转机械的故障类型进行了智能化的识别和分类;将基于IRCMFDE和BA-RVM的故障诊断方法应用于滚动轴承、离心泵和齿轮箱的实验数据分析,并将其与现有故障诊断方法进行了对比分析。研究结果表明:基于IRCMFDE和BA-RVM的故障诊断方法能够有效地识别旋转机械的故障状态,识别准确率分别达到了100%、98%和99%,相比基于RCMFDE、精细复合多尺度熵、精细复合多尺度模糊熵、精细复合多尺度排列熵和精细复合多尺度散布熵的故障特征提取方法,该故障诊断方法的效率和平均识别准确率均优于对比方法,其更适合应用于旋转机械的在线实时故障监测。 展开更多
关键词 改进精细复合多尺度波动散布熵 sort映射 蝙蝠算法优化的相关向量机 旋转机械 故障分类识别
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An Only-Once-Sorting Algorithm
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作者 Xu Xusong Zhou Jianqin Guo Feng (School of Management,Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期38-41,共4页
This paper provides a new sorting algorithm called 'Only-Once-Sorting' algorithm a mathemati cal formula,this algorithm can put elements in the positions they should be stored only once,then compacts them.The ... This paper provides a new sorting algorithm called 'Only-Once-Sorting' algorithm a mathemati cal formula,this algorithm can put elements in the positions they should be stored only once,then compacts them.The algorithm completes sorting a sequence of n elements in a calculation time of O(n ). 展开更多
关键词 mathematical formula onlv-once-sorting sorting algorithm
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PMS-Sorting:A New Sorting Algorithm Based on Similarity
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作者 Hongbin Wang Lianke Zhou +4 位作者 Guodong Zhao Nianbin Wang Jianguo Sun Yue Zheng Lei Chen 《Computers, Materials & Continua》 SCIE EI 2019年第4期229-237,共9页
Borda sorting algorithm is a kind of improvement algorithm based on weighted position sorting algorithm,it is mainly suitable for the high duplication of search results,for the independent search results,the effect is... Borda sorting algorithm is a kind of improvement algorithm based on weighted position sorting algorithm,it is mainly suitable for the high duplication of search results,for the independent search results,the effect is not very good and the computing method of relative score in Borda sorting algorithm is according to the rule of the linear regressive,but position relationship cannot fully represent the correlation changes.aimed at this drawback,the new sorting algorithm is proposed in this paper,named PMS-Sorting algorithm,firstly the position score of the returned results is standardized processing,and the similarity retrieval word string with the query results is combined into the algorithm,the similarity calculation method is also improved,through the experiment,the improved algorithm is superior to traditional sorting algorithm. 展开更多
关键词 Meta search engine result sorting query similarity Borda sorting algorithm position relationship
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An Optimization Approach for Convolutional Neural Network Using Non-Dominated Sorted Genetic Algorithm-Ⅱ
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作者 Afia Zafar Muhammad Aamir +6 位作者 Nazri Mohd Nawi Ali Arshad Saman Riaz Abdulrahman Alruban Ashit Kumar Dutta Badr Almutairi Sultan Almotairi 《Computers, Materials & Continua》 SCIE EI 2023年第3期5641-5661,共21页
In computer vision,convolutional neural networks have a wide range of uses.Images representmost of today’s data,so it’s important to know how to handle these large amounts of data efficiently.Convolutional neural ne... In computer vision,convolutional neural networks have a wide range of uses.Images representmost of today’s data,so it’s important to know how to handle these large amounts of data efficiently.Convolutional neural networks have been shown to solve image processing problems effectively.However,when designing the network structure for a particular problem,you need to adjust the hyperparameters for higher accuracy.This technique is time consuming and requires a lot of work and domain knowledge.Designing a convolutional neural network architecture is a classic NP-hard optimization challenge.On the other hand,different datasets require different combinations of models or hyperparameters,which can be time consuming and inconvenient.Various approaches have been proposed to overcome this problem,such as grid search limited to low-dimensional space and queuing by random selection.To address this issue,we propose an evolutionary algorithm-based approach that dynamically enhances the structure of Convolution Neural Networks(CNNs)using optimized hyperparameters.This study proposes a method using Non-dominated sorted genetic algorithms(NSGA)to improve the hyperparameters of the CNN model.In addition,different types and parameter ranges of existing genetic algorithms are used.Acomparative study was conducted with various state-of-the-art methodologies and algorithms.Experiments have shown that our proposed approach is superior to previous methods in terms of classification accuracy,and the results are published in modern computing literature. 展开更多
关键词 Non-dominated sorted genetic algorithm convolutional neural network hyper-parameter OPTIMIZATION
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基于SORT算法的图像轨迹跟踪混合控制方法 被引量:1
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作者 杜磊 《现代电子技术》 北大核心 2024年第13期32-35,共4页
当目标物体被其他物体部分或完全遮挡时,目标的有效特征点数量会逐渐减少,跟踪器无法继续准确地锁定目标,导致目标轨迹中断。为此,文中研究基于SORT算法的图像轨迹跟踪混合控制方法。选取FCOS算法,利用特征金字塔结构,依据检测头层输出... 当目标物体被其他物体部分或完全遮挡时,目标的有效特征点数量会逐渐减少,跟踪器无法继续准确地锁定目标,导致目标轨迹中断。为此,文中研究基于SORT算法的图像轨迹跟踪混合控制方法。选取FCOS算法,利用特征金字塔结构,依据检测头层输出的目标分类得分、位置回归结果以及中心度检测图像目标。将目标检测结果作为卡尔曼滤波器的输入,利用离散控制过程系统描述视频图像中的目标运动状态,预测目标轨迹。利用SORT算法控制图像目标检测结果与目标轨迹预测结果进行级联匹配与IoU匹配,输出匹配成功的目标,即图像目标轨迹跟踪结果。实验结果表明,该方法可有效地跟踪视频图像目标轨迹,未出现ID变更情况,轨迹中断占比低于0.2%。 展开更多
关键词 sort算法 图像轨迹跟踪 混合控制方法 FCOS算法 卡尔曼滤波器 级联匹配
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Modeling and Optimization of Electrical Discharge Machining of SiC Parameters, Using Neural Network and Non-Dominating Sorting Genetic Algorithm (NSGA II)
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作者 Ramezan Ali MahdaviNejad 《Materials Sciences and Applications》 2011年第6期669-675,共7页
Silicon Carbide (SiC) machining by traditional methods with regards to its high hardness is not possible. Electro Discharge Machining, among non-traditional machining methods, is used for machining of SiC. The present... Silicon Carbide (SiC) machining by traditional methods with regards to its high hardness is not possible. Electro Discharge Machining, among non-traditional machining methods, is used for machining of SiC. The present work is aimed to optimize the surface roughness and material removal rate of electro discharge machining of SiC parameters simultaneously. As the output parameters are conflicting in nature, so there is no single combination of machining parameters, which provides the best machining performance. Artificial neural network (ANN) with back propagation algorithm is used to model the process. A multi-objective optimization method, non-dominating sorting genetic algorithm-II is used to optimize the process. Affects of three important input parameters of process viz., discharge current, pulse on time (Ton), pulse off time (Toff) on electric discharge machining of SiC are considered. Experiments have been conducted over a wide range of considered input parameters for training and verification of the model. Testing results demonstrate that the model is suitable for predicting the response parameters. A pareto-optimal set has been predicted in this work. 展开更多
关键词 Electro DISCHARGE MACHINING Non-Dominating sortING algorithm Neural Network REFEL SIC
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Strengthened Dominance Relation NSGA-Ⅲ Algorithm Based on Differential Evolution to Solve Job Shop Scheduling Problem
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作者 Liang Zeng Junyang Shi +2 位作者 Yanyan Li Shanshan Wang Weigang Li 《Computers, Materials & Continua》 SCIE EI 2024年第1期375-392,共18页
The job shop scheduling problem is a classical combinatorial optimization challenge frequently encountered in manufacturing systems.It involves determining the optimal execution sequences for a set of jobs on various ... The job shop scheduling problem is a classical combinatorial optimization challenge frequently encountered in manufacturing systems.It involves determining the optimal execution sequences for a set of jobs on various machines to maximize production efficiency and meet multiple objectives.The Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ)is an effective approach for solving the multi-objective job shop scheduling problem.Nevertheless,it has some limitations in solving scheduling problems,including inadequate global search capability,susceptibility to premature convergence,and challenges in balancing convergence and diversity.To enhance its performance,this paper introduces a strengthened dominance relation NSGA-Ⅲ algorithm based on differential evolution(NSGA-Ⅲ-SD).By incorporating constrained differential evolution and simulated binary crossover genetic operators,this algorithm effectively improves NSGA-Ⅲ’s global search capability while mitigating pre-mature convergence issues.Furthermore,it introduces a reinforced dominance relation to address the trade-off between convergence and diversity in NSGA-Ⅲ.Additionally,effective encoding and decoding methods for discrete job shop scheduling are proposed,which can improve the overall performance of the algorithm without complex computation.To validate the algorithm’s effectiveness,NSGA-Ⅲ-SD is extensively compared with other advanced multi-objective optimization algorithms using 20 job shop scheduling test instances.The experimental results demonstrate that NSGA-Ⅲ-SD achieves better solution quality and diversity,proving its effectiveness in solving the multi-objective job shop scheduling problem. 展开更多
关键词 Multi-objective job shop scheduling non-dominated sorting genetic algorithm differential evolution simulated binary crossover
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An NC Algorithm for Sorting Real Numbers in <em>O</em>(nlogn/√<span style="font-size: 14px;font-weight: bold;margin-left:-2px;margin-right:2px;border-top:2px solid black;">loglogn</span>) Operations
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作者 Yijie Han Sneha Mishra Md Usman Gani Syed 《Open Journal of Applied Sciences》 2019年第5期403-408,共6页
We apply the recent important result of serial sorting of n real numbers in time to the design of a parallel algorithm for sorting real numbers in time and operations. This is the first NC algorithm known to take oper... We apply the recent important result of serial sorting of n real numbers in time to the design of a parallel algorithm for sorting real numbers in time and operations. This is the first NC algorithm known to take operations for sorting real numbers. 展开更多
关键词 Parallel algorithms sortING sort Real Numbers Complexity
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基于非支配排序遗传算法NSGA-Ⅲ的多目标屏蔽智能优化研究
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作者 王梦琪 郑征 +3 位作者 梅其良 彭超 高静 周岩 《原子能科学技术》 北大核心 2025年第2期422-428,共7页
本文基于第3代非支配排序遗传算法(NSGA-Ⅲ)开展了多目标屏蔽智能优化方法研究。以乏燃料运输船舶为对象,采用多目标智能优化程序建立一维离散纵标计算模型,针对舱盖上方区域屏蔽结构(混凝土和聚乙烯厚度)进行优化设计,最终得到1组优化... 本文基于第3代非支配排序遗传算法(NSGA-Ⅲ)开展了多目标屏蔽智能优化方法研究。以乏燃料运输船舶为对象,采用多目标智能优化程序建立一维离散纵标计算模型,针对舱盖上方区域屏蔽结构(混凝土和聚乙烯厚度)进行优化设计,最终得到1组优化的屏蔽方案。基于优化后的屏蔽方案,建立真实的三维蒙特卡罗计算模型,和基于混凝土、聚乙烯或含硼硅树脂的方案进行对比,评估优化方案的屏蔽效果。评价指标包括屏蔽厚度、重量、总剂量率和价格等。结果显示,基于所开发的多目标屏蔽智能优化方法优化得到的方案各有特点,包含了多个优选的方案,为设计者提供了更丰富的选择。 展开更多
关键词 多目标优化算法 屏蔽 乏燃料运输船舶 第3代非支配排序遗传算法
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发夹式换热器壳程流体传热特性及多目标优化
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作者 李雅侠 王鑫 +2 位作者 李百慧 张丽 张静 《北京化工大学学报(自然科学版)》 北大核心 2025年第2期26-33,共8页
采用数值模拟方法研究了发夹式换热器的壳程流体换热特性,并以提高综合性能指标PEC(总换热量与总功耗之比)和减小无量纲材料成本M'(换热器材料成本与原结构材料成本之比)为目标建立神经网络模型,采用非支配排序遗传算法(NSGA-Ⅱ)对... 采用数值模拟方法研究了发夹式换热器的壳程流体换热特性,并以提高综合性能指标PEC(总换热量与总功耗之比)和减小无量纲材料成本M'(换热器材料成本与原结构材料成本之比)为目标建立神经网络模型,采用非支配排序遗传算法(NSGA-Ⅱ)对无量纲参数折流板间距l'、折流板缺口高度h'、曲率半径r'和雷诺数Re这4个设计变量进行多目标优化。结果显示:在本研究范围内,弯管段的换热量占换热器总换热量的5.0%~16.3%,而功耗仅占总功耗的0.5%~1.0%,说明弯管段结构的存在使得发夹式换热器在功耗小幅增加的情况下换热性能显著提高;参数优化后,得到l'的最佳取值为2.50,h'、r'、Re的最佳取值范围分别为0.33~0.45、0.80~1.30、8000~11000。从优化解集中选取两个代表性解,与原结构相比,优化结构1的PEC提高了25.12%,M'基本不变;优化结构2的PEC提高了17.93%,M'值降低了6.56%,结果表明多目标优化对发夹式换热器结构参数的优化效果明显。 展开更多
关键词 发夹式换热器 结构参数 强化传热 非支配排序遗传算法(NSGA-Ⅱ) 多目标优化
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需求不确定下基于不同碳税机制的双目标多式联运路径优化
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作者 张旭 张海燕 +1 位作者 袁旭梅 秦怡华 《公路交通科技》 北大核心 2025年第2期41-51,共11页
【目标】针对不同碳税机制下的多式联运路径优化问题,考虑了突发性补货或季节性变化等意外因素带来的需求不确定性。【方法】分别在统一碳税机制和分段累进碳税机制下,以总成本和总碳排放量最小为目标,构建随机需求下的双目标0-1路径优... 【目标】针对不同碳税机制下的多式联运路径优化问题,考虑了突发性补货或季节性变化等意外因素带来的需求不确定性。【方法】分别在统一碳税机制和分段累进碳税机制下,以总成本和总碳排放量最小为目标,构建随机需求下的双目标0-1路径优化模型,并基于Monte Carlo模拟和大数定律极大化不确定目标的期望值对模型进行转换。设计改进的非支配排序遗传算法对模型求解以获得满足目标要求的相对较优解。该算法能够在避免“早熟”缺陷的基础上扩大搜索空间与范围以期获得更加优秀的个体与方案。通过具体算例分析模型与算法对于双碳背景下运输问题的适用性,同时探讨不同碳税机制对总成本和总碳排放量的影响及其在需求波动条件下的适用范围和有效性。【结果】双目标策略下企业仅需略微提高成本即可取得一定的减排效果,更适合双碳背景下的运输场景。【结论】企业的碳排放控制效果在固定碳税机制或分段累进碳税机制下均会受到碳税率的影响,但相比统一碳税机制,分段累进碳税机制在高需求不确定时具有更加明显的减排效果与优势,应考虑企业现有能力与减排技术水平,确定合适的碳税率与排放阈值,以调动企业减排积极性。 展开更多
关键词 运输经济 双目标路径优化 改进的非支配排序遗传算法 多式联运 需求不确定 碳税机制
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考虑转港调度的内河港口群多泊位联合配置策略
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作者 高攀 黄柳森 赵旭 《交通运输系统工程与信息》 北大核心 2025年第2期328-337,共10页
为缓解内河港口泊位资源供需时空不匹配问题,将单港泊位分配拓展到腹地高度重叠的内河港口群中,通过考虑不同港口之间的转港调度作业,探索多泊位联合配置优化策略。本文以船舶总成本和在港总时间最小化为目标,建立港口群多泊位联合配置... 为缓解内河港口泊位资源供需时空不匹配问题,将单港泊位分配拓展到腹地高度重叠的内河港口群中,通过考虑不同港口之间的转港调度作业,探索多泊位联合配置优化策略。本文以船舶总成本和在港总时间最小化为目标,建立港口群多泊位联合配置优化模型。依据模型特点,设计改进的非支配排序遗传算法求解模型,并探讨调度实施前后的优化效果。以我国某内河流域的一个港口群为例,对配置模型和优化算法进行可行性验证。实验结果显示:实行联合配置策略的船舶总成本和在港总时间比独立配置均有所降低,且当船舶到港规模由20艘增加到80艘时,实施联合配置策略前后的成本和时间的降低比例平均分别提升至24%和40%左右。同时,当允许转港的船舶数量比例从0增加到20%时,船舶总成本和在港总时间的下降幅度较大;比例超过20%后,呈现边际递减效应。因此,需充分考虑转港调度成本,通过设置适当的转港数量阈值,提升港口群运作效率。 展开更多
关键词 水路运输 联合配置策略 非支配排序遗传算法 内河港口群 多目标优化
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