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THE SOLUTION OF RANDOM EIGENVALUE PROBLEM WITH SMALL STOCHASTIC PROCESSES
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作者 夏宁茂 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期381-391,共11页
This paper considers an eigenvalue problem containing small stochastic processes. For every fixed is, we can use the Prufer substitution to prove the existence of the random solutions lambda(n) and u(n) in the meaning... This paper considers an eigenvalue problem containing small stochastic processes. For every fixed is, we can use the Prufer substitution to prove the existence of the random solutions lambda(n) and u(n) in the meaning of large probability. These solutions can be expanded in epsilon regularly, and their correction terms can be obtained by solving some random linear differential equations. 展开更多
关键词 THE SOLUTION OF random EIGENVALUE problem WITH SMALL STOCHASTIC PROCESSES der
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Random Search Algorithm for the Generalized Weber Problem
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作者 Lev Kazakovtsev 《Journal of Software Engineering and Applications》 2012年第12期59-65,共7页
In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) ... In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) and prove its efficiency for approximate solving this problem by replacing the continuous coordinate values by discrete ones. Version of the algorithm for multiprocessor systems is proposed. Experimental results for a high-performance cluster are given. 展开更多
关键词 DISCRETE Optimization WEBER problem random SEARCH GENETIC Algorithms Parallel ALGORITHM
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孟德尔随机化分析联合PBL教学模式在《牙周病学》本科教学中的探索
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作者 贾睿微 赵浙妤 +3 位作者 朱晓丹 曹金芳 王惠宁 孙晓瑜 《温州医科大学学报》 CAS 2024年第2期169-172,F0003,共5页
目的:将分析疾病因果关系的孟德尔随机化(MR)分析联合以问题为导向的教学方法(PBL)的教学模式应用于《牙周病学》教学,引导学生了解探究牙周病与全身因素之间的关联性,并研究此模式在牙周病教学中的应用效果。方法:以《牙周病学》教材为... 目的:将分析疾病因果关系的孟德尔随机化(MR)分析联合以问题为导向的教学方法(PBL)的教学模式应用于《牙周病学》教学,引导学生了解探究牙周病与全身因素之间的关联性,并研究此模式在牙周病教学中的应用效果。方法:以《牙周病学》教材为主,教授学生MR分析手段为辅,引导学生进行科研探究,提升科研思维和文献查阅能力。选取温州医科大学2019级两个班级的口腔医学专业学生,随机按照班级分为实验组(MR分析联合PBL教学模式)与对照组(课堂授课联合PBL教学模式),实验组53人、对照组54人。课程结束后通过学生课堂表现评分、考试成绩和科研创新思维能力对两种教学模式进行考核评价。结果:经过MR分析联合PBL教学后,实验组学生理论成绩优于对照组,实验组学生试题平均分为84.9±4.6,而对照组的试题平均分为79.2±4.3,差异有统计学意义(P<0.05)。同时,实验组学生课堂表现评分为96.7±5.7,而对照组评分为91.2±4.8,差异有统计学意义(P<0.001)。此外,实验组学生科研创新思维能力优于对照组,具体表现为参与更多科研项目及论文撰写发表。结论:采用MR分析联合PBL的教学模式进行《牙周病学》教学,可加深学生对于牙周疾病与全身疾病关联性的理解与掌握。学生通过查阅科研文献,深入探究补充牙周病与全身疾病之间的关联性,可有效提升学生科研思维能力及文献查阅能力。 展开更多
关键词 孟德尔随机化分析 以问题为导向的教学 牙周病学 教学方法 科研创新思维能力
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增强型群论优化算法求解折扣{0-1}背包问题
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作者 张寒崧 贺毅朝 +2 位作者 王静红 孙菲 李明亮 《计算机科学与探索》 CSCD 北大核心 2024年第6期1526-1542,共17页
群论优化算法(GTOA)是基于群论方法提出的一个离散演化算法,非常适于求解以整型向量为可行解的组合优化问题。为了进一步提高GTOA求解折扣{0-1}背包问题(D{0-1}KP)的性能,首先指出了它的随机线性组合算子(RLCO)未能充分考虑当前个体位... 群论优化算法(GTOA)是基于群论方法提出的一个离散演化算法,非常适于求解以整型向量为可行解的组合优化问题。为了进一步提高GTOA求解折扣{0-1}背包问题(D{0-1}KP)的性能,首先指出了它的随机线性组合算子(RLCO)未能充分考虑当前个体位置信息的不足,基于个体基因保留策略对其进行改进。然后,在随机反向变异算子(IRMO)中引入增强0分量变异策略,用于处理因个体0分量无法及时变异而导致的解的质量下降、种群多样性降低等问题。在改进上述两个算子的基础上,提出了增强型GTOA(EGTOA),并基于它给出求解D{0-1}KP的新方法。随后,将改进策略应用于二进制GTOA(GTOA-2),提出了增强型GTOA-2(EGTOA-2)及其求解D{0-1}KP的新方法。为了验证EGTOA和EGTOA-2的性能提高程度与优异性,分别利用它们求解四类大规模D{0-1}KP实例,通过与GTOA、GTOA-2以及求解D{0-1}KP的已有8个最先进算法的比较表明:EGTOA和EGTOA-2求得最优解的能力比GTOA和GTOA-2提高了至少1.14倍,比8个最先进算法提高了5%~60%,它们的平均性能比GTOA、GTOA-2以及8个最先进算法的性能更佳。因此,EGTOA和EGTOA-2是当前求解D{0-1}KP的最佳算法。 展开更多
关键词 群论优化算法 组合优化问题 折扣{0-1}背包问题 随机变异
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基于离散哈里斯鹰算法求解车辆路径问题
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作者 郭玉洁 徐洪智 《计算机工程与设计》 北大核心 2024年第6期1764-1770,共7页
针对带容量约束车辆路径问题,提出一种离散哈里斯鹰算法。在哈里斯鹰算法的基础上,根据车辆路径的编解码特点,重新定义算法在全局搜索和局部开发阶段的更新策略;在全局搜索阶段利用随机插入和反转策略更新哈里斯鹰个体的位置,提高算法... 针对带容量约束车辆路径问题,提出一种离散哈里斯鹰算法。在哈里斯鹰算法的基础上,根据车辆路径的编解码特点,重新定义算法在全局搜索和局部开发阶段的更新策略;在全局搜索阶段利用随机插入和反转策略更新哈里斯鹰个体的位置,提高算法的全局开发能力;在局部开发阶段利用转移算子和移除算子设计哈里斯鹰个体的更新机制,提高算法的局部精细化搜索能力;通过改进逃逸能量平衡全局搜索和局部开发能力。实验结果表明,重定义的更新策略均能有效提升算法效率,将该算法和其它启发式算法的结果相比较,所提算法在求解精度和稳定性方面更具优势。 展开更多
关键词 离散哈里斯鹰算法 容量约束车辆路径问题 随机反转 插入操作 转移算子 移除算子 改进逃逸能量
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Novel Partitioned Time-Stepping Algorithms for Fast Computation of Random Interface-Coupled Problems with Uncertain Parameters
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作者 Yizhong Sun Jiangshan Wang Haibiao Zheng 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2024年第1期145-180,共36页
The simulation of multi-domain,multi-physics mathematical models with uncertain parameters can be quite demanding in terms of algorithm design and com-putation costs.Our main objective in this paper is to examine a ph... The simulation of multi-domain,multi-physics mathematical models with uncertain parameters can be quite demanding in terms of algorithm design and com-putation costs.Our main objective in this paper is to examine a physical interface coupling between two random dissipative systems with uncertain parameters.Due to the complexity and uncertainty inherent in such interface-coupled problems,un-certain diffusion coefficients or friction parameters often arise,leading to consid-ering random systems.We employ Monte Carlo methods to produce independent and identically distributed deterministic heat-heat model samples to address ran-dom systems,and adroitly integrate the ensemble idea to facilitate the fast calcu-lation of these samples.To achieve unconditional stability,we introduce the scalar auxiliary variable(SAV)method to overcome the time constraints of the ensemble implicit-explicit algorithm.Furthermore,for a more accurate and stable scheme,the ensemble data-passing algorithm is raised,which is unconditionally stable and convergent without any auxiliary variables.These algorithms employ the same co-efficient matrix for multiple linear systems and enable easy parallelization,which can significantly reduce the computational cost.Finally,numerical experiments are conducted to support the theoretical results and showcase the unique features of the proposed algorithms. 展开更多
关键词 Scalar auxiliary variable ensemble algorithm random interface-coupled problems implicit-explicit partitioned method data-passing partitioned method
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On the upper bounds of (1,0)-super solutions for the regular balanced random (k,2s)-SAT problem
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作者 Yongping WANG Daoyun XU Jincheng ZHOU 《Frontiers of Computer Science》 SCIE EI CSCD 2024年第4期139-146,共8页
This paper explores the conditions which make a regular balancedrandom(k,2s)-CNFformula(1,O)-unsatisfiable with high probability.The conditions also make a random instance of the regular balanced(k-1,2(k-1)s)-SAT prob... This paper explores the conditions which make a regular balancedrandom(k,2s)-CNFformula(1,O)-unsatisfiable with high probability.The conditions also make a random instance of the regular balanced(k-1,2(k-1)s)-SAT problem unsatisfiable with high probability,where the instance obeys a distribution which differs from the distribution obeyed by a regular balanced random(k-1,2(k-1)s)-CNF formula.Let F be a regular balanced random(k,2s)-CNF formula where k≥3,then there exists a number so such that F is(1,O)-unsatisfiable with high probability if s>so.A numerical solution of the number so when k e(5,6,...,14)is given to conduct simulated experiments.The simulated experiments verify the theoretical result.Besides,the experiments also suggest that F is(1,O)-satisfiable with high probability if s is less than a certain value. 展开更多
关键词 regular balanced random(k 2s)-SAT problem (1 0)-super solution upper bound
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基于空间聚焦机制的混沌随机蚁群算法
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作者 禹博文 游晓明 刘升 《智能计算机与应用》 2024年第9期1-9,共9页
为了提高蚁群算法在大规模旅行商问题上的性能,本文提出了一种基于空间聚焦机制的混沌随机蚁群算法(CRACS)。首先,使用空间聚焦机制将旅行商问题划分为几个子类;其次,提出了一种改进混沌随机蚁群算法来求解子类;最后,将各个子类路线进... 为了提高蚁群算法在大规模旅行商问题上的性能,本文提出了一种基于空间聚焦机制的混沌随机蚁群算法(CRACS)。首先,使用空间聚焦机制将旅行商问题划分为几个子类;其次,提出了一种改进混沌随机蚁群算法来求解子类;最后,将各个子类路线进行聚焦,选择最优连接路线动态连接各个子类,形成旅行商问题的最优解决方案。本文选取不同规模的典型旅行商问题进行了仿真实验,实验结果表明本文提出的算法在大规模问题上具有优秀的性能,相比于其他智能算法具有更优质的解和更快的搜索速度。 展开更多
关键词 蚁群算法 旅行商问题 空间聚焦机制 混沌随机
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研究生“随机信号处理”课程研究性教学的实践
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作者 李艳玲 占建伟 张辉 《教育教学论坛》 2024年第30期10-13,共4页
围绕研究生的创新能力培养问题,探索与实践研究生“随机信号处理”课程研究性教学,提出并实践了基于知识图谱的问题链条设计、基于“课前自学、课中导学、课后拓学”的研究性教学过程设计,以及基于多元化的研究性教学考核评价等策略或方... 围绕研究生的创新能力培养问题,探索与实践研究生“随机信号处理”课程研究性教学,提出并实践了基于知识图谱的问题链条设计、基于“课前自学、课中导学、课后拓学”的研究性教学过程设计,以及基于多元化的研究性教学考核评价等策略或方法,并以最小均方自适应算法的研究性教学为例,展示了具体的教学过程和学生课后开放性作业的部分成果,实践结果表明研究性教学能有效促进学生的问题意识培养和应用创新能力的提升。 展开更多
关键词 研究性教学 随机信号处理 知识图谱 问题链条 LMS算法
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基于新颖二进制人工蜂群算法求解带权集合覆盖问题
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作者 孙菲 贺毅朝 +3 位作者 张寒崧 李明亮 王丽娜 高泽贤 《计算机应用研究》 CSCD 北大核心 2024年第9期2722-2731,共10页
带权集合覆盖问题(WSCP)是一个著名的NP-hard问题。为了利用人工蜂群算法(ABC)高效求解带权集合覆盖问题,提出了一个新颖二进制ABC(记作nBABC)。在nBABC中,首先提出了随机学习和继承性相结合的全局进化算子,以提高算法的全局勘探能力。... 带权集合覆盖问题(WSCP)是一个著名的NP-hard问题。为了利用人工蜂群算法(ABC)高效求解带权集合覆盖问题,提出了一个新颖二进制ABC(记作nBABC)。在nBABC中,首先提出了随机学习和继承性相结合的全局进化算子,以提高算法的全局勘探能力。其次,基于动态调整策略提出了自适应随机取反算子,以维持勘探与开发的平衡。在借鉴近似算法的思想提出处理WSCP不可行解的修复算法WSCP-GRA和优化算法WSCP-GOA的基础上,利用nBABC给出了求解WSCP的一个新方法。为了验证nBABC求解WSCP的高效性,利用它求解OR-Library中45个WSCP实例,与多个算法的比较表明:nBABC能够求得所有实例的最优值,比已有求解WSCP的算法更具竞争力。 展开更多
关键词 演化算法 带权集合覆盖问题 二进制人工蜂群算法 随机学习机制 修复与优化
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A Proxy Signature Scheme as Secure as Decisional Diffie-Hellman Problem 被引量:1
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作者 LURong-xing CAOZhen-fu 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期186-190,共5页
Based on decisional Difiie-Hcllman problem, we propose a simpleproxy-protected signature scheme In the random oracle model, we also carry out the strict securityproof for the proposed scheme. The security of the propo... Based on decisional Difiie-Hcllman problem, we propose a simpleproxy-protected signature scheme In the random oracle model, we also carry out the strict securityproof for the proposed scheme. The security of the proposed scheme is not loosely related to thediscrete logarithm assumption hut tightly related to the decisional Diffie-Hellman assumption in therandom oracle model. 展开更多
关键词 proxy signature decisional Diffie-Heliman problem random oracle model
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SOLUTIONS FOR A SYSTEM OF NONLINEAR RANDOM INTEGRAL AND DIFFERENTIAL EQUATIONS UNDER WEAK TOPOLOGY
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作者 丁协平 王凡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第8期721-737,共17页
In this paper, a Darbao type random fixed point theorem for a system of weak continuous random operators with random domain is first proved. When, by using the theorem, some existence criteria of random solutions for ... In this paper, a Darbao type random fixed point theorem for a system of weak continuous random operators with random domain is first proved. When, by using the theorem, some existence criteria of random solutions for a systems of nonlinear random Volterra integral equations relative to the weak topology in Banach spaces are given. As applications, some existence theorems of weak random solutions for the random Cauchy problem of a system of nonlinear random differential equations are obtained, as well as the existence of extremal random solutions and random comparison results for these systems of random equations relative to weak topology in Banach spaces. The corresponding results of Szep, Mitchell-Smith, Cramer-Lakshmikantham, Lakshmikantham-Leela and Ding are improved and generalized by these theorems. 展开更多
关键词 system of nonlinear random Volterra integral equations random Cauchy problem extremal random solution comparison result weak topology in Banach space
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Acoustic stop bands in almost-periodic and weakly randomized stratified media:perturbation analysis
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作者 S.Guenneau A.B.Movchan +1 位作者 N.V.Movchan J.Trebicki 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第5期549-556,共8页
In this paper, we analyze the effect of both deter- ministic and random perturbations of a regular multi-layered elastic structure on its stop band properties. The tool of choice is the transfer matrix method, which i... In this paper, we analyze the effect of both deter- ministic and random perturbations of a regular multi-layered elastic structure on its stop band properties. The tool of choice is the transfer matrix method, which is both versatile and easy to implement. In both cases, we find that the stop-bands widen. We observe the appearance of very narrow pass-bands within the stop-bands, which can be observed in other instances in optics. 展开更多
关键词 Transmission problem Small random perturbations Stop bands
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Mean Square Numerical Methods for Initial Value Random Differential Equations
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作者 Magdy A. El-Tawil Mohammed A. Sohaly 《Open Journal of Discrete Mathematics》 2011年第2期66-84,共19页
In this paper, the random Euler and random Runge-Kutta of the second order methods are used in solving random differential initial value problems of first order. The conditions of the mean square convergence of the nu... In this paper, the random Euler and random Runge-Kutta of the second order methods are used in solving random differential initial value problems of first order. The conditions of the mean square convergence of the numerical solutions are studied. The statistical properties of the numerical solutions are computed through numerical case studies. 展开更多
关键词 random Differential Equations Mean SQUARE SENSE Second random Variable Initial Value problems random EULER METHOD random Runge Kutta-2 METHOD
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融合常识库和语法特征的数学应用题题意理解 被引量:1
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作者 刘清堂 马鑫倩 +2 位作者 周洁 吴林静 周鹏霄 《计算机应用》 CSCD 北大核心 2023年第2期356-364,共9页
数学问题的题意理解是实现自动解题的关键,然而现有研究对情境复杂、参数较多等特征的应用题实现题意理解的准确率较低,尚没有很好的优化解决方案。基于此,以语境复杂的古典概型应用题为突破点,提出了融合常识库和语法特征的数学应用题... 数学问题的题意理解是实现自动解题的关键,然而现有研究对情境复杂、参数较多等特征的应用题实现题意理解的准确率较低,尚没有很好的优化解决方案。基于此,以语境复杂的古典概型应用题为突破点,提出了融合常识库和语法特征的数学应用题题意理解方法。首先,结合古典概型应用题的文本和结构特征,构建了包含7类关键解题参数的古典概型题意表征模型;然后,根据该模型将应用题题意理解任务转化为解题参数识别问题,并设计了融合多维语法特征的条件随机场(CRF)题意参数识别方法来解决这个问题。进一步地,针对隐性参数识别问题设计了常识参数补全模块,并提出了融合常识库和语法特征的数学应用题题意理解方法。以新东方在线网站和21世纪教育在线题库中的948道古典概型应用题为实验语料进行实验。实验结果表明,所提方法的各题意参数识别F1平均值达到93.56%,高于最大熵模型(MaxEnt)、双向长短期记忆网络-条件随机场(BiLSTM-CRF)和传统CRF方法;并且题意理解准确率达到66.54%,显著高于上述其他方法,验证了所提方法对古典概型应用题题意理解的有效性。 展开更多
关键词 题意理解 自动解题 条件随机场 古典概型应用题 常识库 语法特征
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Research on Location-Routing Problem with Empirical Analysis for Regional Logistics Distribution
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作者 Qian Zhang 《Applied Mathematics》 2014年第15期2305-2310,共6页
The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate th... The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities. 展开更多
关键词 DISTRIBUTION Facilities MULTI-OBJECTIVE Location-Routing problem (MLRP) MATHEMATICAL Models random Analysis
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Counting and Randomly Generating <i>k</i>-Ary Trees
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作者 James F. Korsh 《Applied Mathematics》 2021年第12期1210-1215,共6页
<em>k</em>-ary trees are one of the most basic data structures in Computer Science. A new method is presented to determine how many there are with n nodes. This method gives additional insight into their s... <em>k</em>-ary trees are one of the most basic data structures in Computer Science. A new method is presented to determine how many there are with n nodes. This method gives additional insight into their structure and provides a new algo-rithm to efficiently generate such a tree randomly. 展开更多
关键词 Combinatorial problems k-Ary Trees random Generation
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An Alternative Algorithm for Vehicle Routing Problem with Time Windows for Daily Deliveries 被引量:2
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作者 Nor Edayu Abdul Ghani S. Sarifah Radiah Shariff Siti Meriam Zahari 《Advances in Pure Mathematics》 2016年第5期342-350,共9页
This study attempts to solve vehicle routing problem with time window (VRPTW). The study first identifies the real problems and suggests some recommendations on the issues. The technique used in this study is Genetic ... This study attempts to solve vehicle routing problem with time window (VRPTW). The study first identifies the real problems and suggests some recommendations on the issues. The technique used in this study is Genetic Algorithm (GA) and initialization applied is random population method. The objective of the study is to assign a number of vehicles to routes that connect customers and depot such that the overall distance travelled is minimized and the delivery operations are completed within the time windows requested by the customers. The analysis reveals that the problems experienced in vehicle routing with time window can be solved by GA and retrieved for optimal solutions. After a thorough study on VRPTW, it is highly recommended that a company should implement the optimal routes derived from the study to increase the efficiency and accuracy of delivery with time insertion. 展开更多
关键词 Vehicle Routing problem with Time Windows (VRPTW) Genetic Algorithm (GA) random Population Method
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指向深度学习的课堂教学
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作者 柏灵 侯影 徐向红 《大学数学》 2023年第4期98-105,共8页
基于内容的结构关联性,针对二维随机变量函数的分布的知识点进行课堂教学设计.层层递进的问题链引导和推动着学生的思考,最终达到高阶性深度学习的目的.课后通过对学生的调查问卷进行对比分析,显示本教学设计对教学内容的分析和拓展得... 基于内容的结构关联性,针对二维随机变量函数的分布的知识点进行课堂教学设计.层层递进的问题链引导和推动着学生的思考,最终达到高阶性深度学习的目的.课后通过对学生的调查问卷进行对比分析,显示本教学设计对教学内容的分析和拓展得到学生的高认可度,教学质量和效果明显提高. 展开更多
关键词 深度学习 问题驱动 概率密度函数 随机变量的函数
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RANDOM MICROSTRUCTURE FINITE ELEMENT METHOD FOR EFFECTIVE NONLINEAR PROPERTIES OF COMPOSITE MATERIALS
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作者 瞿鹏程 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第2期1-6,共6页
Some theoretical methods have been reported to deal with nonlinear problems of composite materials but the accuracy is not so good. In the meantime, a lot of linear problems are difficult to be managed by the theoreti... Some theoretical methods have been reported to deal with nonlinear problems of composite materials but the accuracy is not so good. In the meantime, a lot of linear problems are difficult to be managed by the theoretical methods. The present study aims to use the developed method, the random microstructure finite element method, to deal with these nonlinear problems. In this paper, the random microstructure finite element method is used to deal with all three kinds of nonlinear property problems of composite materials. The analyzed results suggest the influences of the nonlinear phenomena on the effective properties of composite materials are significant and the random microstructure finite element method is an effective tool to investigate the nonlinear problems. 展开更多
关键词 random microstructure finite element method effective property composite materials nonlinear property problems
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