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求解TSP的离散野马优化算法
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作者 蔡延光 方春城 +1 位作者 吴艳林 陈华君 《计算机工程与应用》 CSCD 北大核心 2024年第1期145-153,共9页
针对求解TSP问题,提出一种新的元启发式算法离散野马优化算法(DWHO),应用最小位置匹配值法(MPMV)对求解结果进行离散化解码;为提高算法搜索能力,结合野马放牧、交配、领导者交流与选拔行为,引入变邻域搜索策略,增强了算法的局部搜索能... 针对求解TSP问题,提出一种新的元启发式算法离散野马优化算法(DWHO),应用最小位置匹配值法(MPMV)对求解结果进行离散化解码;为提高算法搜索能力,结合野马放牧、交配、领导者交流与选拔行为,引入变邻域搜索策略,增强了算法的局部搜索能力、加快算法收敛速度。选取TSPLIB标准库33个算例进行实验,并与交换序列人工蜂群算法(ABCSS)、离散蜘蛛猴优化算法(DSMO)两种算法进行比较。实验结果表明,DWHO求得的最优解与ABCSS、DSMO两种算法的最优解相比,最优解改进率最大值分别达到4.52%和3.41%。同时,将离散野马优化算法求解TSP收敛速度与以上两种算法进行比较,其收敛速度具有一定的优势。结果表明离散野马优化算法求解能力和精度具有优势。 展开更多
关键词 离散野马优化算法 旅行商问题 最小位置匹配值法 最优解改进率
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智能算法在TSP问题中的应用研究
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作者 王麟珠 郑晓斌 《机电技术》 2024年第2期4-6,32,共4页
TSP问题是典型的路径优化问题,具有解决物流路径规划等实际应用意义。为解决TSP问题,文章研究了遗传算法、禁忌搜索算法、蚁群算法和模拟退火算法,以遍历31个省会城市为例,运用MATLAB软件编程仿真。结果表明:蚁群算法优化效果较好,且一... TSP问题是典型的路径优化问题,具有解决物流路径规划等实际应用意义。为解决TSP问题,文章研究了遗传算法、禁忌搜索算法、蚁群算法和模拟退火算法,以遍历31个省会城市为例,运用MATLAB软件编程仿真。结果表明:蚁群算法优化效果较好,且一致性高,但运行效率不高,可混合运用遗传算法和蚁群算法,以提高运行效率和求解质量。 展开更多
关键词 tsp 遗传算法 禁忌搜索算法 蚁群算法 模拟退火算法
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TSP问题求解在电气设计过程中的应用
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作者 魏志刚 毛东 张家铭 《建筑电气》 2024年第6期43-47,共5页
通过介绍求解旅行商问题(TSP)的特点,论述采用启发式算法中的最近邻点算法、交叉迁回优化算法的原理和计算方法,提出TSP问题高质量求解的思路,并实现基于AutoLISP编程开发技术在AutoCAD平台上计算机自动生成最优布线功能,可提高工程技... 通过介绍求解旅行商问题(TSP)的特点,论述采用启发式算法中的最近邻点算法、交叉迁回优化算法的原理和计算方法,提出TSP问题高质量求解的思路,并实现基于AutoLISP编程开发技术在AutoCAD平台上计算机自动生成最优布线功能,可提高工程技术人员的设计效率。 展开更多
关键词 tsp问题 最优路径 AuotCAD AUTOLISP编程 最近邻点算法 自动布线 交叉路径 迁回路径
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TSP/OSCE模式联合微课教学在临床护理实践教学中的应用价值
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作者 姚佳 潘立萍 +1 位作者 黄惠桥 陈湘 《中文科技期刊数据库(引文版)教育科学》 2024年第3期41-45,共5页
探究在临床护理实践教学中,采用教师模拟标准化病人(TSP)/临床医师技能培训考试系统(OSCE)联合微课模式的教学效果。方法 研究开展时间为2022年1月—2023年12月,对象为所选取240名医院实习护生,其中2022年的120名护生接受传统培训模式,... 探究在临床护理实践教学中,采用教师模拟标准化病人(TSP)/临床医师技能培训考试系统(OSCE)联合微课模式的教学效果。方法 研究开展时间为2022年1月—2023年12月,对象为所选取240名医院实习护生,其中2022年的120名护生接受传统培训模式,作为对照组;2023年的120护生接受TSP/OSCE模式联合微课的教学模式,作为观察组;于实习期间、实习结束后考察护生的护理操作技能及理论考试平均成绩,利用改良版迷你临床演练评估量表(Mini-CEX)测评护生的临床实践能力,评估评判性思维能力,通过问卷调查形式评价护生对教学满意度。结果 培训后,2组护生护理操作技能、理论考试平均成绩均升高,且观察组升高幅度更大(P<0.05);与对照组做对比,观察组培训后的Mini-CEX(临床评估、查体操作、健康教育、临床判断、组织效能、人文关怀)评分高(P<0.05);实习后2组的CTDI-CV评分均提高,且观察组改变更明显(P<0.05);教学满意度对比,观察组护生明显高(P<0.05)。结论 临床护理实践教学中实行TSP/OSCE模式联合微课教学模式,有利于提高实习生的护理操作技能水平及理论知识掌握程度,并发展其临床实践能力,取得满意的教学效果。 展开更多
关键词 tsp/OSCE模式 微课教学 临床护理实践教学 应用价值
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TSP与瞬变电磁成果三维化在隧道断层含水预报中的应用
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作者 张硕 甄大勇 +1 位作者 刘康 易轲 《中国铁路》 北大核心 2024年第5期75-81,共7页
隧道开挖过程中经常遇到断层、节理发育密集带等地质异常段落,并且断层带易形成地下水的运移通道。提前查清此类地质问题,可以最大程度降低施工过程中的安全风险。隧道超前地质预报为前期勘察工作的延续,在施工期间通过物探、钻探等手... 隧道开挖过程中经常遇到断层、节理发育密集带等地质异常段落,并且断层带易形成地下水的运移通道。提前查清此类地质问题,可以最大程度降低施工过程中的安全风险。隧道超前地质预报为前期勘察工作的延续,在施工期间通过物探、钻探等手段可以有效判释隧道开挖前方一定距离的地质情况。首次将TSP法与瞬变电磁成果三维化相结合,应用于某在建铁路隧道的超前预报工作中。根据前期勘察资料,结合TSP探测成果确定断层发育段落,然后在掌子面附近实施多角度瞬变电磁探测;基于Voxler软件实现瞬变电磁成果的三维化展示,通过三维成果判断断层的含水性,综合分析瞬变电磁低阻异常三维分布特征及TSP波速异常段落,圈定出断层破碎范围及富水性空间分布情况,并对富水区域提前进行钻探泄水。通过实际开挖验证分析,结果表明:2种方法相结合可以准确探测隧道开挖前方的围岩完整性及含水情况,有效降低施工风险,为隧道开挖方案优化提供有效资料。 展开更多
关键词 tsp 瞬变电磁成果三维化 铁路隧道 波速异常 电阻率 超前地质预报
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A Comparative Study of Metaheuristic Optimization Algorithms for Solving Real-World Engineering Design Problems
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作者 Elif Varol Altay Osman Altay Yusuf Ovik 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期1039-1094,共56页
Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as ... Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as industry,automotive,construction,machinery,and interdisciplinary research.However,there are established optimization techniques that have shown effectiveness in addressing these types of issues.This research paper gives a comparative study of the implementation of seventeen new metaheuristic methods in order to optimize twelve distinct engineering design issues.The algorithms used in the study are listed as:transient search optimization(TSO),equilibrium optimizer(EO),grey wolf optimizer(GWO),moth-flame optimization(MFO),whale optimization algorithm(WOA),slimemould algorithm(SMA),harris hawks optimization(HHO),chimp optimization algorithm(COA),coot optimization algorithm(COOT),multi-verse optimization(MVO),arithmetic optimization algorithm(AOA),aquila optimizer(AO),sine cosine algorithm(SCA),smell agent optimization(SAO),and seagull optimization algorithm(SOA),pelican optimization algorithm(POA),and coati optimization algorithm(CA).As far as we know,there is no comparative analysis of recent and popular methods against the concrete conditions of real-world engineering problems.Hence,a remarkable research guideline is presented in the study for researchersworking in the fields of engineering and artificial intelligence,especiallywhen applying the optimization methods that have emerged recently.Future research can rely on this work for a literature search on comparisons of metaheuristic optimization methods in real-world problems under similar conditions. 展开更多
关键词 Metaheuristic optimization algorithms real-world engineering design problems multidisciplinary design optimization problems
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An Effective Meshless Approach for Inverse Cauchy Problems in 2D and 3D Electroelastic Piezoelectric Structures
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作者 Ziqiang Bai Wenzhen Qu Guanghua Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2955-2972,共18页
In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within... In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within each sub-domain,explicit formulas for the necessary partial derivatives of the partial differential equations(PDEs)can be obtained through the application of Taylor series expansion and moving-least square approximation methods.Consequently,the method generates a sparse coefficient matrix,exhibiting a banded structure,making it highly advantageous for large-scale engineering computations.In this study,we present the application of the GFDM to numerically solve inverse Cauchy problems in two-and three-dimensional piezoelectric structures.Through our preliminary numerical experiments,we demonstrate that the proposed GFDMapproach shows great promise for accurately simulating coupled electroelastic equations in inverse problems,even with 3%errors added to the input data. 展开更多
关键词 Generalized finite difference method meshless method inverse Cauchy problems piezoelectric problems electroelastic analysis
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems
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作者 Chein-Shan Liu Chung-Lun Kuo Chih-Wen Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3189-3208,共20页
To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection techniq... To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit function.We can quickly determine the optimal values of the parameters within a preferred rage using the golden section search algorithm.The novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical examples.Moreover,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being ill-posed.The optimal MQ-RBF is extremely accurate.We further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11). 展开更多
关键词 Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method
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Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation
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作者 LI Zhi-yu LI Kun +2 位作者 CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期191-200,共10页
A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in ... A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results. 展开更多
关键词 Sturm-Liouville problem interface condition oscillatory solution
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不同耕作模式下农机作业对PM_(2.5)、PM_(10)和TSP排放的影响
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作者 段改莲 陈卫文 +2 位作者 王揽月 周明源 邢广青 《农业工程》 2024年第3期53-55,共3页
农机可以提高作业效率,但也会加剧农田扬尘的排放,对农田区域大气造成污染,影响空气质量。以北京市昌平区玉米收获与小麦耕种环节农机作业为研究对象,揭示了农机作业对农田PM_(2.5)、PM_(10)和TSP 3种颗粒物排放的影响。结果表明,在小... 农机可以提高作业效率,但也会加剧农田扬尘的排放,对农田区域大气造成污染,影响空气质量。以北京市昌平区玉米收获与小麦耕种环节农机作业为研究对象,揭示了农机作业对农田PM_(2.5)、PM_(10)和TSP 3种颗粒物排放的影响。结果表明,在小麦耕种阶段,农机作业对农田扬尘浓度的影响程度由大到小依次为秸秆切碎、旋耕、免耕播种和传统播种;传统耕作模式排放的颗粒物总量为保护性耕作模式的4.6~6.7倍,保护性耕作模式减少了作业环节,减少了农机下地次数,从根本上减少了农田扬尘。 展开更多
关键词 耕作模式 农机作业 扬尘排放 空气质量 PM_(2.5) PM_(10) tsp
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Problematic Use of Video Games in Schools in Northern Benin (2023)
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作者 Ireti Nethania Elie Ataigba David Sinet Koivogui +6 位作者 Damega Wenkourama Marcos Tohou Eurydice Elvire Djossou Anselme Djidonou Francis Tognon Tchegnonsi Prosper Gandaho Josiane Ezin Houngbe 《Open Journal of Psychiatry》 2024年第2期120-141,共22页
Objective: To study the problematic use of video games among secondary school students in the city of Parakou in 2023. Methods: Descriptive cross-sectional study conducted in the commune of Parakou from December 2022 ... Objective: To study the problematic use of video games among secondary school students in the city of Parakou in 2023. Methods: Descriptive cross-sectional study conducted in the commune of Parakou from December 2022 to July 2023. The study population consisted of students regularly enrolled in public and private secondary schools in the city of Parakou for the 2022-2023 academic year. A two-stage non-proportional stratified sampling technique combined with simple random sampling was adopted. The Problem Video Game Playing (PVP) scale was used to assess problem gambling in the study population, while anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS). Results: A total of 1030 students were included. The mean age of the pupils surveyed was 15.06 ± 2.68 years, with extremes of 10 and 28 years. The [13 - 18] age group was the most represented, with a proportion of 59.6% (614) in the general population. Females predominated, at 52.8% (544), with a sex ratio of 0.89. The prevalence of problematic video game use was 24.9%, measured using the Video Game Playing scale. Associated factors were male gender (p = 0.005), pocket money under 10,000 cfa (p = 0.001) and between 20,000 - 90,000 cfa (p = 0.030), addictive family behavior (p < 0.001), monogamous family (p = 0.023), good relationship with father (p = 0.020), organization of video game competitions (p = 0.001) and definite anxiety (p Conclusion: Substance-free addiction is struggling to attract the attention it deserves, as it did in its infancy everywhere else. This study complements existing data and serves as a reminder of the need to focus on this group of addictions, whose problematic use of video games remains the most frequent due to its accessibility and social tolerance. Preventive action combined with curative measures remains the most effective means of combating the problem at national level. 展开更多
关键词 Gaming problem Video Games BENIN 2023
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Association of preschool children behavior and emotional problems with the parenting behavior of both parents
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作者 Su-Mei Wang Shuang-Qin Yan +4 位作者 Fang-Fang Xie Zhi-Ling Cai Guo-Peng Gao Ting-Ting Weng Fang-Biao Tao 《World Journal of Clinical Cases》 SCIE 2024年第6期1084-1093,共10页
BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.... BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors. 展开更多
关键词 CHILDREN Preschool age PARENTING BEHAVIORAL Parenting problems
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Quafu-Qcover:Explore combinatorial optimization problems on cloud-based quantum computers
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作者 许宏泽 庄伟峰 +29 位作者 王正安 黄凯旋 时运豪 马卫国 李天铭 陈驰通 许凯 冯玉龙 刘培 陈墨 李尚书 杨智鹏 钱辰 靳羽欣 马运恒 肖骁 钱鹏 顾炎武 柴绪丹 普亚南 张翼鹏 魏世杰 增进峰 李行 龙桂鲁 金贻荣 于海峰 范桁 刘东 胡孟军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期104-115,共12页
We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and c... We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight graph.The core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA circuit.Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers.Compared to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed performance.Additionally,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum devices.This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity.The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous processing.Moreover,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization problems.We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers. 展开更多
关键词 quantum cloud platform combinatorial optimization problems quantum software
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TSP结合TEM在风险围岩隧道超前地质预报中的应用
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作者 林川 《铁道勘察》 2024年第1期54-62,共9页
为了排查隧道施工过程中潜在的地质风险、指导隧道安全开挖掘进,针对某高速铁路风险围岩隧道浅埋段和可溶岩段,利用TSP和TEM两种方法开展超前地质预报。TSP预报可对掌子面前方围岩状况进行远距离宏观预测,能划定断层、破碎带、地下水等... 为了排查隧道施工过程中潜在的地质风险、指导隧道安全开挖掘进,针对某高速铁路风险围岩隧道浅埋段和可溶岩段,利用TSP和TEM两种方法开展超前地质预报。TSP预报可对掌子面前方围岩状况进行远距离宏观预测,能划定断层、破碎带、地下水等不良地质体的位置和大致规模;TEM预报可在掌子面附近开展多角度、多方位测量,能判定开挖面前方一定空间范围内不良围岩特征,特别是地下水、岩溶的分布及规模。研究表明,TSP震波对应的负反射和低速异常突出反映围岩岩性变化及岩体破碎程度,依据纵、横波速起伏特征可大致判定地下水发育情况;TEM低阻异常直观体现围岩富水状态,并可推测岩溶发育及分布状况,视电阻率阻值变化密集区对应了围岩岩体破碎。研究结果表明,采用两种或多种方法结合开展综合预报,可提升预报结论的准确度和可靠度,TSP结合TEM成功预报的应用实例可为类似风险围岩隧道的超前地质预报提供参考和借鉴。 展开更多
关键词 高速铁路 风险围岩隧道 浅埋段 可溶岩段 tsp TEM 超前地质预报
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An Immune-Inspired Approach with Interval Allocation in Solving Multimodal Multi-Objective Optimization Problems with Local Pareto Sets
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作者 Weiwei Zhang Jiaqiang Li +2 位作者 Chao Wang Meng Li Zhi Rao 《Computers, Materials & Continua》 SCIE EI 2024年第6期4237-4257,共21页
In practical engineering,multi-objective optimization often encounters situations where multiple Pareto sets(PS)in the decision space correspond to the same Pareto front(PF)in the objective space,known as Multi-Modal ... In practical engineering,multi-objective optimization often encounters situations where multiple Pareto sets(PS)in the decision space correspond to the same Pareto front(PF)in the objective space,known as Multi-Modal Multi-Objective Optimization Problems(MMOP).Locating multiple equivalent global PSs poses a significant challenge in real-world applications,especially considering the existence of local PSs.Effectively identifying and locating both global and local PSs is a major challenge.To tackle this issue,we introduce an immune-inspired reproduction strategy designed to produce more offspring in less crowded,promising regions and regulate the number of offspring in areas that have been thoroughly explored.This approach achieves a balanced trade-off between exploration and exploitation.Furthermore,we present an interval allocation strategy that adaptively assigns fitness levels to each antibody.This strategy ensures a broader survival margin for solutions in their initial stages and progressively amplifies the differences in individual fitness values as the population matures,thus fostering better population convergence.Additionally,we incorporate a multi-population mechanism that precisely manages each subpopulation through the interval allocation strategy,ensuring the preservation of both global and local PSs.Experimental results on 21 test problems,encompassing both global and local PSs,are compared with eight state-of-the-art multimodal multi-objective optimization algorithms.The results demonstrate the effectiveness of our proposed algorithm in simultaneously identifying global Pareto sets and locally high-quality PSs. 展开更多
关键词 Multimodal multi-objective optimization problem local PSs immune-inspired reproduction
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Dirac method for nonlinear and non-homogenous boundary value problems of plates
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作者 Xiaoye MAO Jiabin WU +2 位作者 Junning ZHANG Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期15-38,共24页
The boundary value problem plays a crucial role in the analytical investigation of continuum dynamics. In this paper, an analytical method based on the Dirac operator to solve the nonlinear and non-homogeneous boundar... The boundary value problem plays a crucial role in the analytical investigation of continuum dynamics. In this paper, an analytical method based on the Dirac operator to solve the nonlinear and non-homogeneous boundary value problem of rectangular plates is proposed. The key concept behind this method is to transform the nonlinear or non-homogeneous part on the boundary into a lateral force within the governing function by the Dirac operator, which linearizes and homogenizes the original boundary, allowing one to employ the modal superposition method for obtaining solutions to reconstructive governing equations. Once projected into the modal space, the harmonic balance method(HBM) is utilized to solve coupled ordinary differential equations(ODEs)of truncated systems with nonlinearity. To validate the convergence and accuracy of the proposed Dirac method, the results of typical examples, involving nonlinearly restricted boundaries, moment excitation, and displacement excitation, are compared with those of the differential quadrature element method(DQEM). The results demonstrate that when dealing with nonlinear boundaries, the Dirac method exhibits more excellent accuracy and convergence compared with the DQEM. However, when facing displacement excitation, there exist some discrepancies between the proposed approach and simulations;nevertheless, the proposed method still accurately predicts resonant frequencies while being uniquely capable of handling nonuniform displacement excitations. Overall, this methodology offers a convenient way for addressing nonlinear and non-homogenous plate boundaries. 展开更多
关键词 rectangular plate Dirac operator nonlinear boundary time-dependent boundary boundary value problem
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Using Improved Particle Swarm Optimization Algorithm for Location Problem of Drone Logistics Hub
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作者 Li Zheng Gang Xu Wenbin Chen 《Computers, Materials & Continua》 SCIE EI 2024年第1期935-957,共23页
Drone logistics is a novel method of distribution that will become prevalent.The advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for ... Drone logistics is a novel method of distribution that will become prevalent.The advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for the company’s transportation operations.Logistics firms must discern the ideal location for establishing a logistics hub,which is challenging due to the simplicity of existing models and the intricate delivery factors.To simulate the drone logistics environment,this study presents a new mathematical model.The model not only retains the aspects of the current models,but also considers the degree of transportation difficulty from the logistics hub to the village,the capacity of drones for transportation,and the distribution of logistics hub locations.Moreover,this paper proposes an improved particle swarm optimization(PSO)algorithm which is a diversity-based hybrid PSO(DHPSO)algorithm to solve this model.In DHPSO,the Gaussian random walk can enhance global search in the model space,while the bubble-net attacking strategy can speed convergence.Besides,Archimedes spiral strategy is employed to overcome the local optima trap in the model and improve the exploitation of the algorithm.DHPSO maintains a balance between exploration and exploitation while better defining the distribution of logistics hub locations Numerical experiments show that the newly proposed model always achieves better locations than the current model.Comparing DHPSO with other state-of-the-art intelligent algorithms,the efficiency of the scheme can be improved by 42.58%.This means that logistics companies can reduce distribution costs and consumers can enjoy a more enjoyable shopping experience by using DHPSO’s location selection.All the results show the location of the drone logistics hub is solved by DHPSO effectively. 展开更多
关键词 Drone logistics location problem mathematical model DIVERSITY particle swarm optimization
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Data-Driven Learning Control Algorithms for Unachievable Tracking Problems
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作者 Zeyi Zhang Hao Jiang +1 位作者 Dong Shen Samer S.Saab 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期205-218,共14页
For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to in... For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best approximation.Subsequently, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete information.To address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain design.The input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings. 展开更多
关键词 Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems
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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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