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1.
针对高原地区航材配送中心选址决策特点,构建了航材配送中心选址指标体系,提出了基于二元语义的群决策选址方法,给出了基于二元语义群决策的航材配送中心选址步骤.通过实例得出了备选点的综合评价值,证明了该方法的有效性.  相似文献   

2.
评估两个句子的语义相似性是文本检索和文本摘要等自然语言处理任务的重要组成部分.学者利用深度神经网络执行该任务,然而它们依赖于上下文独立词向量,从而导致性能不佳.为了缓解该问题,采用预训练模型BERT替换传统的词向量,并提出交叉自注意力以增强两个句子的语义,然后与BERT结合.在提出的模型中,为了实现交叉自注意力操作,设计了向量的对齐方法.最后,将BERT输出输入一个双向循环神经网络,以稳定性能,克服BERT自身带来的波动性.实验中,采用3个公开数据集DBMI2019、CDD-ref和CDD-ful对提出的混合模型进行评价.实验结果表明,由于使用了BERT生成的语境词向量,提出模型的性能始终优于现存方法;交叉自注意力实现了彼此的语义交互而增强了句对的语义,使得相似句对的语义差异更小,而不相似句对的语义差异更大,提高了相似性评估的性能.最终,提出模型在DBMI2019、CDD-ref和CDD-ful上分别取得了0.846,0.849和0.845的皮尔逊相关系数,超越了直接以[CLS]输出向量作为评估的方法.  相似文献   

3.
深入研究了犹豫模糊二元语义多属性决策问题。首先利用幂均算子给出了犹豫模糊二元语义集的均值函数,并基于均匀分布概率准则和二元语义的距离测度提出了犹豫模糊二元语义集两两比较的可能度公式,进一步给出了可能度排序公式的性质。针对属性值为犹豫模糊二元语义集的多属性决策问题,提出了一种基于熵权的多属性决策方法。最后结合实际问题,验证了该方法的有效性和可行性。  相似文献   

4.
针对高原地区航材配送中心选址决策特点,构建了航材配送中心选址指标体系,提出了基于二元语义的群决策选址方法,给出了基于二元语义群决策的航材配送中心选址步骤.通过实例得出了备选点的综合评价值,证明了方法的有效性.  相似文献   

5.
针对具有多粒度语言评价信息的多属性群决策问题,提出了一种基于二元语义信息处理和相对熵的群决策方法。该方法首先给出了多粒度语言评价信息一致化为由基本语言评价集表示的相同粒度二元语义信息的方法,然后对于属性权重信息不完全的情形,建立了基于相对熵的多目标规划模型获得相应的属性权重,并利用二元语义的集结算子对语言评价信息进行加权集成,从而获得各个决策方案的排序和择优结果;最后给出一个实例分析,说明了该方法的有效性和可行性。  相似文献   

6.
软件Agent遇到语义二义性时无法正确地为用户解决矛盾问题.利用本体支持语义互操作的特点,在软件Agent策略生成机制中引入复合元本体,加入Agent智能引导的人机交互方法,实现了具有语义歧义消除能力的可拓策略生成系统.当用户输入的问题信息语义模糊时,Agent根据本体中的知识与用户交互,逐步理解用户的信息语义,直到能为用户生成解决矛盾问题的策略.以旅游与购物问题为例进行了实验,结果表明了软件Agent策略生成的语义互操作能力得到了提高.  相似文献   

7.
针对专家给出二维语言评价信息的低碳供应商评选问题,提出一种基于二维二元语义和模糊AHP-TODIM的方法。该方法首先提出改进的二元语义模型,基于此定义二维二元语义及其加权平均算子。接着构建低碳供应商评价的指标体系。最后,将专家给出的二维语言评价信息转化为二维二元语义,使用模糊AHP法计算指标权重,并利用二维二元语义加权平均算子集结信息,在此基础上将TODIM方法扩展到二维二元语义环境以获取低碳供应商排序。案例分析说明了所提出的方法的有效性。  相似文献   

8.
针对具有不同粒度语言评价矩阵和属性未知的群决策问题,给出了一种基于二元语义和TOPSIS算法的群决策方法。在该方法中,首先给出了不同粒度语言评价矩阵一致化为由基本语言评价集表示的二元语义信息的方法;然后引入TOPSIS的方法,结合二元语义形式计算规则,确定未知的属性客观权重,利用二元语义集结算子,得到单个决策者对方案的评价值;再通过T-OWA算子对各决策者给出的评价信息进行集结和方案选优;最后给出了一个算例。  相似文献   

9.
基于二元语义信息处理的项目群决策方法   总被引:1,自引:0,他引:1  
项目群的决策是项目群管理的一个重要组成部分,是一个涉及众多不确定性因素的系统工程。本文给出项目群中子项目的评价依据,在此基础上,将二元语义信息处理的方法应用于项目群决策,给出了基于二元语义信息处理的项目群决策的算法步骤,最后通过一个算例,说明该方法的有效性和实用性。  相似文献   

10.
相辉 《运筹与管理》2009,18(4):44-49,59
提出了"时序多属性群决策"的新问题,并选用"二元语义"方法对语言型时序多属性群决策方法进行了研究.构建了能同时兼顾线性算子与非线性算子特点的二元语义组合加权平均算子,并针对信息集结中综合评价结果对集结路径的依赖问题,确立了基于"偏差缩减"的"多路径集成"思路,同时给出了"方差最小法"、"可靠性加权法"、"客观差异法"等3种合成方法.最后,将方法用于目前理论及实务界广泛关注的"服务创新方案选择"问题中,验证了方法的有效性.  相似文献   

11.
Variations of the latent semantic indexing (LSI) method in information retrieval (IR) require the computation of singular subspaces associated with the k dominant singular values of a large m × n sparse matrix A, where k?min(m,n). The Riemannian SVD was recently generalized to low‐rank matrices arising in IR and shown to be an effective approach for formulating an enhanced semantic model that captures the latent term‐document structure of the data. However, in terms of storage and computation requirements, its implementation can be much improved for large‐scale applications. We discuss an efficient and reliable algorithm, called SPK‐RSVD‐LSI, as an alternative approach for deriving the enhanced semantic model. The algorithm combines the generalized Riemannian SVD and the Lanczos method with full reorthogonalization and explicit restart strategies. We demonstrate that our approach performs as well as the original low‐rank Riemannian SVD method by comparing their retrieval performance on a well‐known benchmark document collection. Copyright 2004 John Wiley & Sons, Ltd.  相似文献   

12.
结合遗传算法全局高效搜索和牛顿法局部细致搜索的优势,充分利用一种算法的优点弥补另一种算法的不足,进而引入一种基于遗传算法和牛顿法的联合算法,并将联合算法应用于反演地表发射率的函数关系中.结果表明,联合算法中由遗传算法提供的初始值使得牛顿法下降的速度快,且很快趋于稳定,达到精度要求;而由任意初始值提供给牛顿法,目标函数下降到一定阶段后反而有所回升,然后才保持稳定,且经和联合算法迭代相同的次数后,目标函数的值仍然非常大,远远达不到要求.因此,从可行性、计算效率上看,联合算法均优于单纯的牛顿法,是一种性能稳定,计算高效的下降方法.  相似文献   

13.
This paper presents an efficient hybrid metaheuristic solution for multi-depot vehicle routing with time windows (MD-VRPTW). MD-VRPTW involves the routing of a set of vehicles with limited capacity from a set of depots to a set of geographically dispersed customers with known demands and predefined time windows. The present work aims at using a hybrid metaheuristic algorithm in the class of High-Level Relay Hybrid (HRH) which works in three levels and uses an efficient genetic algorithm as the main optimization algorithm and tabu search as an improvement method. In the genetic algorithm various heuristics incorporate local exploitation in the evolutionary search. An operator deletion- retrieval strategy is executed which shows the efficiency of the inner working of the proposed method. The proposed algorithm is applied to solve the problems of the standard Cordeau??s Instances. Results show that proposed approach is quite effective, as it provides solutions that are competitive with the best known in the literature.  相似文献   

14.
How might domain knowledge constrain a genetic algorithm and systematically impact the algorithm’s traversal of the search space? In particular, in this paper the hypothesis is advanced that a semantic tree of financial knowledge can be used to influence the results of a genetic algorithm for financial investing problems. An algorithm is described, called the “Memetic Algorithm for Domain Knowledge”, and is instantiated in a software system. In mutation experiments, this system chooses financial ratios to use as inputs to a neural logic network which classifies stocks as likely to increase or decrease in value. The mutation is guided by a semantic tree of financial ratios. In crossover experiments, this system solves a portfolio optimization problem in which components of an individual represent weights on stocks; knowledge in the form of a semantic tree of industries determines the order in which components are sorted in individuals. Both synthetic data and real-world data are used. The experimental results show that knowledge can be used to reach higher fitness individuals more quickly. More interestingly, the results show how conceptual distance in the human knowledge can correspond to distance between evolutionary individuals and their fitness. In other words, knowledge might be dynamically used to at times increase the step size in a search algorithm or at times to decrease the step size. These results shed light on the role of knowledge in evolutionary computation and are part of the larger body of work to delineate how domain knowledge might usefully constrain the genetic algorithm.  相似文献   

15.
16.
Genetic algorithms have attracted a good deal of interest in the heuristic search community. Yet there are several different types of genetic algorithms with varying performance and search characteristics. In this article we look at three genetic algorithms: an elitist simple genetic algorithm, the CHC algorithm and Genitor. One problem in comparing algorithms is that most test problems in the genetic algorithm literature can be solved using simple local search methods. In this article, the three algorithms are compared using new test problems that are not readily solved using simple local search methods. We then compare a local search method to genetic algorithms for geometric matching and examine a hybrid algorithm that combines local and genetic search. The geometric matching problem matches a model (e.g., a line drawing) to a subset of lines contained in a field of line fragments. Local search is currently the best known method for solving general geometric matching problems.  相似文献   

17.
A DERIVATIVE-FREE ALGORITHM FOR UNCONSTRAINED OPTIMIZATION   总被引:1,自引:0,他引:1  
In this paper a hybrid algorithm which combines the pattern search method and the genetic algorithm for unconstrained optimization is presented. The algorithm is a deterministic pattern search algorithm,but in the search step of pattern search algorithm,the trial points are produced by a way like the genetic algorithm. At each iterate, by reduplication,crossover and mutation, a finite set of points can be used. In theory,the algorithm is globally convergent. The most stir is the numerical results showing that it can find the global minimizer for some problems ,which other pattern search algorithms don't bear.  相似文献   

18.
多目标规划的一种混合遗传算法   总被引:3,自引:0,他引:3  
本文利用遗传算法的全局搜索内能力及直接搜索算法的局部优化能力,提出了一种用于多目标规划的混合遗传算法.与Pareto遗传算法相比.本文提出的算法能提高多目标遗传算法优化搜索效率,并保证了能得到适舍决策者要求的Pareto最优解.最后,理论与实践证明其有有效性.  相似文献   

19.
A comparison of local search methods for flow shop scheduling   总被引:1,自引:0,他引:1  
Local search techniques are widely used to obtain approximate solutions to a variety of combinatorial optimization problems. Two important categories of local search methods are neighbourhood search and genetic algorithms. Commonly used neighbourhood search methods include descent, threshold accepting, simulated annealing and tabu search. In this paper, we present a computational study that compares these four neighbourhood search methods, a genetic algorithm, and a hybrid method in which descent is incorporated into the genetic algorithm. The performance of these six local search methods is evaluated on the problem of scheduling jobs in a permutation flow shop to minimize the total weighted completion time. Based on the results of extensive computational tests, simulated annealing is found to generate better quality solutions than the other neighborhood search methods. However, the results also indicate that the hybrid genetic descent algorithm is superior to simulated annealing.  相似文献   

20.
In this paper, both scatter search (SS) and genetic algorithms (GAs) are studied for the NP-Hard optimization variant of the satisfiability problem, namely MAX-SAT. First, we investigate a new selection strategy based on both fitness and diversity to choose individuals to participate in the reproduction phase of a genetic algorithm. The resulting algorithm is enhanced in two ways leading to two genetic algorithm variants: the first one uses a uniform crossover. The second one uses a specific crossover operator (to MAX-SAT). The crossover operator is combined with an improved stochastic local search (SLS). The crossover operator is used to identify promising regions while the stochastic local search performs an intensified search of solutions around these regions. Secondly, we propose a scatter search variant for MAX-SAT. Both the SS and the GAs implementations share the solution selection strategy, the improved SLS method and the combination operator. Experiments on several instances from MAX-SAT libraries are performed to show and compare the effectiveness of our approaches. The computational experiments show that both (SS) and (GAs) with a stochastic local search (SLS) improvement technique outperform a classical genetic algorithm (without SLS). The two metaheuristics are able of balancing search diversification and intensification which leads to good results. In general, the specific genetic algorithm with a (SLS) improvement technique and a specific combination method provides competitive results and finds solutions of a higher quality than a scatter search.  相似文献   

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