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Research on Scholarship Evaluation System based on Decision Tree Algorithm 被引量:1
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作者 YIN Xiao WANG Ming-yu 《电脑知识与技术》 2015年第3X期11-13,共3页
Under the modern education system of China, the annual scholarship evaluation is a vital thing for many of the collegestudents. This paper adopts the classification algorithm of decision tree C4.5 based on the betteri... Under the modern education system of China, the annual scholarship evaluation is a vital thing for many of the collegestudents. This paper adopts the classification algorithm of decision tree C4.5 based on the bettering of ID3 algorithm and constructa data set of the scholarship evaluation system through the analysis of the related attributes in scholarship evaluation information.And also having found some factors that plays a significant role in the growing up of the college students through analysis and re-search of moral education, intellectural education and culture&PE. 展开更多
关键词 data mining scholarship evaluation system decision tree algorithm C4.5 algorithm
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The Design of the Minimum Spanning Tree Algorithms
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作者 Zhicheng LIU Bo JIANG 《Intelligent Information Management》 2009年第1期56-59,共4页
Based on the graphic theory and improved genetic algorithm,an improved genetic algorithm to search the minimum spanning trees is given . The algorithm uses binary code to represent the problem of minimum spanning tree... Based on the graphic theory and improved genetic algorithm,an improved genetic algorithm to search the minimum spanning trees is given . The algorithm uses binary code to represent the problem of minimum spanning trees. It designs the corresponding fitness function,operator and few controlling strategies to improve its speed and evolutionary efficiency.Only one solution can be gotten with running traditional al-gorithem atone time.The new algorithm can get a set of the solutions with higher probability in a shorter time.The experiment shows that it has a better performance than traditional methods. 展开更多
关键词 minimum SPANNING tree GENETIC algorithm PATTERN
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基于关联分析FP-Tree算法的企业风险信息数据在线挖掘方法
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作者 庞泰 翁巍 +2 位作者 孟灿 赵蕾 牛红伟 《无线互联科技》 2024年第11期75-77,共3页
现阶段的数据挖掘方法缺少对数据关联分析的过程,挖掘效果较差,故文章提出基于关联分析频繁模式树(FrequentPattern Tree, FP-Tree)算法的企业风险信息数据在线挖掘方法。选取与企业风险相关的信息指标,收集有关数据并进行预处理操作后... 现阶段的数据挖掘方法缺少对数据关联分析的过程,挖掘效果较差,故文章提出基于关联分析频繁模式树(FrequentPattern Tree, FP-Tree)算法的企业风险信息数据在线挖掘方法。选取与企业风险相关的信息指标,收集有关数据并进行预处理操作后,设计一种考虑关联分析的FP-Tree算法,生成FP-Tree节点的条件模式树挖掘频繁项集,计算满足最小置信度的频繁项集,实现企业风险信息数据在线挖掘。实验结果表明,所用方法挖掘量和挖掘效率较高。 展开更多
关键词 关联分析FP-tree算法 企业风险信息数据 在线挖掘方法 数据挖掘
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ball tree优化的自动驾驶仿真测试场景生成方法 被引量:1
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作者 秦琴 谷文军 《计算机应用研究》 CSCD 北大核心 2023年第9期2781-2784,2791,共5页
基于场景的仿真测试方法可以有效加速自动驾驶汽车的测试进程,但是传统的采样方法面对高维度采样空间时无法维持高效性,提出了一种ball tree优化的仿真测试场景采样方法,并基于Carla模拟器构建了仿真测试场景自动化生成框架验证算法的... 基于场景的仿真测试方法可以有效加速自动驾驶汽车的测试进程,但是传统的采样方法面对高维度采样空间时无法维持高效性,提出了一种ball tree优化的仿真测试场景采样方法,并基于Carla模拟器构建了仿真测试场景自动化生成框架验证算法的有效性。分别使用随机采样方法、基于KD tree结构的最近邻采样方法与基于ball tree结构的最近邻采样方法进行场景参数采样,并生成不同天气要素下的仿真测试场景进行验证。最后将仿真过程与人工方法进行对比。结果表明,提出方法相对于人工方法具有11.38倍场景制作速度的提升,且相对于KD tree结构的采样方法的场景生成速度提升了27.97%。 展开更多
关键词 自动驾驶 场景生成 最近邻算法 ball tree CARLA
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Extracting impervious surfaces from multi-source satellite imagery based on unified conceptual model by decision tree algorithm 被引量:4
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作者 QIAO Yu,LIU HuiPing,BAI Mu,WANG XiaoDong & ZHOU XiaoLuo School of Geography,Beijing Normal University,Beijing 100875,China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第S1期68-74,共7页
Extraction of impervious surfaces is one of the necessary processes in urban change detection.This paper derived a unified conceptual model (UCM) from the vegetation-impervious surface-soil (VIS) model to make the ext... Extraction of impervious surfaces is one of the necessary processes in urban change detection.This paper derived a unified conceptual model (UCM) from the vegetation-impervious surface-soil (VIS) model to make the extraction more effective and accurate.UCM uses the decision tree algorithm with indices of spectrum and texture,etc.In this model,we found both dependent and independent indices for multi-source satellite imagery according to their similarity and dissimilarity.The purpose of the indices is to remove the other land-use and land-cover types (e.g.,vegetation and soil) from the imagery,and delineate the impervious surfaces as the result.UCM has the same steps conducted by decision tree algorithm.The Landsat-5 TM image (30 m) and the Satellite Probatoire d’Observation de la Terre (SPOT-4) image (20 m) from Chaoyang District (Beijing) in 2007 were used in this paper.The results show that the overall accuracy in Landsat-5 TM image is 88%,while 86.75% in SPOT-4 image.It is an appropriate method to meet the demand of urban change detection. 展开更多
关键词 MULTI-SOURCE satellite IMAGERY impervious surfaces extraction VIS model DECISION tree algorithm
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Enhancing Navigability:An Algorithm for Constructing Tag Trees 被引量:1
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作者 Chong Chen Pengcheng Luo 《Journal of Data and Information Science》 CSCD 2017年第2期56-75,共20页
Purpose: This study introduces an algorithm to construct tag trees that can be used as a userfriendly navigation tool for knowledge sharing and retrieval by solving two issues of previous studies, i.e. semantic drift... Purpose: This study introduces an algorithm to construct tag trees that can be used as a userfriendly navigation tool for knowledge sharing and retrieval by solving two issues of previous studies, i.e. semantic drift and structural skew.Design/methodology/approach: Inspired by the generality based methods, this study builds tag trees from a co-occurrence tag network and uses the h-degree as a node generality metric. The proposed algorithm is characterized by the following four features:(1) the ancestors should be more representative than the descendants,(2) the semantic meaning along the ancestor-descendant paths needs to be coherent,(3) the children of one parent are collectively exhaustive and mutually exclusive in describing their parent, and(4) tags are roughly evenly distributed to their upper-level parents to avoid structural skew. Findings: The proposed algorithm has been compared with a well-established solution Heymann Tag Tree(HTT). The experimental results using a social tag dataset showed that the proposed algorithm with its default condition outperformed HTT in precision based on Open Directory Project(ODP) classification. It has been verified that h-degree can be applied as a better node generality metric compared with degree centrality.Research limitations: A thorough investigation into the evaluation methodology is needed, including user studies and a set of metrics for evaluating semantic coherence and navigation performance.Practical implications: The algorithm will benefit the use of digital resources by generating a flexible domain knowledge structure that is easy to navigate. It could be used to manage multiple resource collections even without social annotations since tags can be keywords created by authors or experts, as well as automatically extracted from text.Originality/value: Few previous studies paid attention to the issue of whether the tagging systems are easy to navigate for users. The contributions of this study are twofold:(1) an algorithm was developed to construct tag trees with consideration given to both semanticcoherence and structural balance and(2) the effectiveness of a node generality metric, h-degree, was investigated in a tag co-occurrence network. 展开更多
关键词 Semantic coherence Structural balance Tag tree Resources navigation algorithm
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Improved Ternary-tree Algorithm for Contention Resolution over Random Multi-access Channel
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作者 GAOFei ZHAODong-feng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2001年第2期35-39,共5页
This paper studies the tree based contention resolution algorithm over a random multi access channel, and proposes a new algorithm model which is named Improved Ternary tree Algorithm( ITA ). The channel throughp... This paper studies the tree based contention resolution algorithm over a random multi access channel, and proposes a new algorithm model which is named Improved Ternary tree Algorithm( ITA ). The channel throughput over blocked access reaches 0 422. The analytical expression and computer simulation results indicate that the performance of ITA is better than the basic binary and ternary tree algorithm. 展开更多
关键词 contention resolution tree based algorithms mean slot length THROUGHPUT blocked access
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An efficient embedding tree matching algorithm based on metaphoric dependency syntax tree
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作者 冯少荣 肖文俊 《Journal of Central South University》 SCIE EI CAS 2009年第2期275-279,共5页
To find out all dependency relationships in which metaphors probably exist between syntax constituents in a given sentence,a dependency tree matching algorithm oriented to Chinese metaphor processing is proposed based... To find out all dependency relationships in which metaphors probably exist between syntax constituents in a given sentence,a dependency tree matching algorithm oriented to Chinese metaphor processing is proposed based on a research of unordered tree inclusion matching.In this algorithm,the pattern library is composed of formalization dependency syntax trees that are derived from large-scale metaphor sentences.These kinds of metaphor sentences are saved in the pattern library in advance.The main process of this algorithm is up-down searching and bottom-up backtracking revising.The algorithm discovers potential metaphoric structures in Chinese sentences from metaphoric dependency pattern library.Finally,the feasibility and efficiency of the new matching algorithm are further testified by the results of a series of experiments on dependency pattern library.Hence,accurate dependency relationships can be achieved through this algorithm. 展开更多
关键词 pattern recognition tree matching algorithm dependency tree rule matching metaphor information processing
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Algorithms for degree-constrained Euclidean Steiner minimal tree 被引量:1
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作者 Zhang Jin Ma Liang Zhang Liantang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期735-741,共7页
A new problem of degree-constrained Euclidean Steiner minimal tree is discussed, which is quite useful in several fields. Although it is slightly different from the traditional degree-constrained minimal spanning tree... A new problem of degree-constrained Euclidean Steiner minimal tree is discussed, which is quite useful in several fields. Although it is slightly different from the traditional degree-constrained minimal spanning tree, it is also NP-hard. Two intelligent algorithms are proposed in an attempt to solve this difficult problem. Series of numerical examples are tested, which demonstrate that the algorithms also work well in practice. 展开更多
关键词 DEGREE-CONSTRAINED Euclidean Steiner minimal tree simulated annealing ant algorithm
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TREE ENUMERATION AND TREE ALGORITHM COMPLEXITY COMPUTATION
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作者 王振宇 《Chinese Science Bulletin》 SCIE EI CAS 1992年第23期2004-2009,共6页
Algorithm complexity analysis over tree structures has drawn much attention in recent years. Ph. Flajolet made the complexity analysis for recursive descent algorithm over trees by establishing a complexity measure ta... Algorithm complexity analysis over tree structures has drawn much attention in recent years. Ph. Flajolet made the complexity analysis for recursive descent algorithm over trees by establishing a complexity measure table for constructions in a formal tree algorithm description language. The so-called concept 'additive complexity algorithm over tree structures' was also introduced, which is parallel to the concept 'additive enumeration problems over trees', and some results that could only be used to recursive algorithms were obtained. 展开更多
关键词 tree ENUMERATION algorithm COMPLEXITY analysis simply GENERATED tree FAMILY
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Generating Decision Trees Method Based on Improved ID3 Algorithm
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作者 杨明 郭树旭 王隽 《China Communications》 SCIE CSCD 2011年第5期151-156,共6页
The ID3 algorithm is a classical learning algorithm of decision tree in data mining.The algorithm trends to choosing the attribute with more values,affect the efficiency of classification and prediction for building a... The ID3 algorithm is a classical learning algorithm of decision tree in data mining.The algorithm trends to choosing the attribute with more values,affect the efficiency of classification and prediction for building a decision tree.This article proposes a new approach based on an improved ID3 algorithm.The new algorithm introduces the importance factor λ when calculating the information entropy.It can strengthen the label of important attributes of a tree and reduce the label of non-important attributes.The algorithm overcomes the flaw of the traditional ID3 algorithm which tends to choose the attributes with more values,and also improves the efficiency and flexibility in the process of generating decision trees. 展开更多
关键词 decision tree ID3 algorithm importance factor attribute value
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Constructing Multicast Routing Tree for Inter-cloud Data Transmission:An Approximation Algorithmic Perspective
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作者 Jun Huang Shihao Li Qiang Duan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期514-522,共9页
Networking plays a crucial role in cloud computing especially in an inter-cloud environment, where data communications among data centers located at different geographical sites form the foundation of inter-cloud fede... Networking plays a crucial role in cloud computing especially in an inter-cloud environment, where data communications among data centers located at different geographical sites form the foundation of inter-cloud federation. Data transmissions required for inter-cloud federation in the complex inter-cloud networking system are often point-to-multi points, which calls for a more effective and efficient multicast routing algorithm in complex networking systems. In this paper, we investigate the multicast routing problem in the inter-cloud context with K constraints where K ≥ 2. Unlike most of existing algorithms that are too complex to be applied in practical scenarios, a novel and fast algorithm for establishing multicast routing tree for interclouds is proposed. The proposed algorithm leverages an entropybased process to aggregate all weights into a comprehensive metric, and then uses it to search a multicast tree(MT) on the basis of the shortest path tree(SPT). We conduct complexity analysis and extensive simulations for the proposed algorithm from the approximation perspective. Both analytical and experimental results demonstrate that the algorithm is more efficient than a representative multi-constrained multicast routing algorithm in terms of both speed and accuracy, and thus we believe that the proposed algorithm is applicable to the inter-cloud environment. 展开更多
关键词 Index Terms--Entropy inter-clouds multicast tree (MT) rout-ing algorithm shortest path tree (SPT).
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Efficient Binary Tree Multiclass SVM Using Genetic Algorithms for Vowels Recognition
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作者 Boutkhil Sidaoui Kaddour Sadouni 《通讯和计算机(中英文版)》 2012年第10期1116-1123,共8页
关键词 元音识别 遗传算法 SVM 二叉树 支持向量机 多类分类 测试阶段 训练时间
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A Dynamic Programming Algorithm for the Ridersharing Problem Restricted with Unique Destination and Zero Detour on Trees
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作者 Yiming Li Huiqiang Lu +1 位作者 Zhiqian Ye Xiao Zhou 《Journal of Applied Mathematics and Physics》 2017年第9期1678-1685,共8页
We deal with the problem of sharing vehicles by individuals with similar itineraries which is to find the minimum number of drivers, each of which has a vehicle capacity and a detour to realize all trips. Recently, Gu... We deal with the problem of sharing vehicles by individuals with similar itineraries which is to find the minimum number of drivers, each of which has a vehicle capacity and a detour to realize all trips. Recently, Gu et al. showed that the problem is NP-hard even for star graphs restricted with unique destination, and gave a polynomial-time algorithm to solve the problem for paths restricted with unique destination and zero detour. In this paper we will give a dynamic programming algorithm to solve the problem in polynomial time for trees restricted with unique destination and zero detour. In our best knowledge it is a first polynomial-time algorithm for trees. 展开更多
关键词 Dynamic PROGRAMMING algorithm Rideshare tree
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STATE SPACE TREE METHOD AND EXACT DECOMPOSITION ALGORITHM FOR FINDING NETWORK OVERALL RELIABILITY
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作者 黄汝激 《Journal of Electronics(China)》 1990年第4期296-305,共10页
First,the state space tree method for finding communication network overall re-liability is presented.It directly generates one disjoint tree multilevel polynomial of a networkgraph.Its advantages are smaller computat... First,the state space tree method for finding communication network overall re-liability is presented.It directly generates one disjoint tree multilevel polynomial of a networkgraph.Its advantages are smaller computational effort(its computing time complexity is O(en_l),where e is the number of edges and n_l is the number of leaves)and shorter resulting expression.Second,based on it an exact decomposition algorithm for finding communication network overallreliability is presented by applying the hypergraph theory.If we use it to carry out the m-timedecomposition of a network graph,the communication network scale which can be analyzed by acomputer can be extended to m-fold. 展开更多
关键词 Communication NETWORK Overall RELIABILITY GRAPH HYPERGRAPH State space tree EXACT decomposition algorithm
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Nearest neighbor search algorithm for GBD tree spatial data structure
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作者 Yutaka Ohsawa Takanobu Kurihara Ayaka Ohki 《重庆邮电大学学报(自然科学版)》 2007年第3期253-259,共7页
This paper describes the nearest neighbor (NN) search algorithm on the GBD(generalized BD) tree. The GBD tree is a spatial data structure suitable for two-or three-dimensional data and has good performance characteris... This paper describes the nearest neighbor (NN) search algorithm on the GBD(generalized BD) tree. The GBD tree is a spatial data structure suitable for two-or three-dimensional data and has good performance characteristics with respect to the dynamic data environment. On GIS and CAD systems, the R-tree and its successors have been used. In addition, the NN search algorithm is also proposed in an attempt to obtain good performance from the R-tree. On the other hand, the GBD tree is superior to the R-tree with respect to exact match retrieval, because the GBD tree has auxiliary data that uniquely determines the position of the object in the structure. The proposed NN search algorithm depends on the property of the GBD tree described above. The NN search algorithm on the GBD tree was studied and the performance thereof was evaluated through experiments. 展开更多
关键词 邻居搜索算法 GBD树 空间数据结构 动态数据环境 地理信息系统 计算机辅助设计
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位姿约束下的双向扩展机械臂路径规划方法 被引量:1
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作者 刘光辉 高嘉豪 +2 位作者 孟月波 徐胜军 韩九强 《计算机集成制造系统》 EI CSCD 北大核心 2024年第7期2389-2405,共17页
针对机械臂路径规划方法存在的规划效率低、连杆通过性差、路径粗糙等问题,以渐进最优快速随机搜索树RRT*为基础,提出一种位姿约束下的双向扩展机械臂路径规划方法(PCO-BT-RRT*)。首先,设计目标偏置引导的双向扩展RRT*算法(BT-RRT*),改... 针对机械臂路径规划方法存在的规划效率低、连杆通过性差、路径粗糙等问题,以渐进最优快速随机搜索树RRT*为基础,提出一种位姿约束下的双向扩展机械臂路径规划方法(PCO-BT-RRT*)。首先,设计目标偏置引导的双向扩展RRT*算法(BT-RRT*),改进了RRT*算法的初始化过程,将起始点和目标点分别作为两棵随机树的初始节点,并通过目标偏置策略引导其以一定概率相向生长,加快探索未知区域,在保证路径代价较低的同时提升路径生成速度。其次,提出一种位姿约束路径优化策略(PCO),采用机械臂运动学模型和碰撞检测规则共同约束新节点扩展过程,寻找机械臂可达空间内的避障路径;对生成路径剪枝剔冗,缩短可行路径长度,同时对消冗节点以迭代调整的方式进行平滑优化,提高路径生成质量。通过仿真实验分析,验证了所提方法在路径规划问题上的显著性成效;在自主研发的BIM信息融合下建筑砌筑系统进行真机避障测试,验证了该方法的实用性。 展开更多
关键词 机械臂路径规划 RRT*算法 双向扩展 位姿约束 路径平滑
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Efficient Minimum Spanning Tree Algorithms on the Reconfigurable Mesh
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作者 万颖瑜 许胤龙 +1 位作者 顾晓东 陈国良 《Journal of Computer Science & Technology》 SCIE EI CSCD 2000年第2期116-125,共10页
The reconfigurable mesh consists of an array of processors interconnected by a reconfigurable bus system. The bus system can be used to dynamically obtain various interconnection patterns among the processors. Recent... The reconfigurable mesh consists of an array of processors interconnected by a reconfigurable bus system. The bus system can be used to dynamically obtain various interconnection patterns among the processors. Recently, this model has attracted a lot of attention. In this paper, two efficient algorithms are proposed for computing the minimum spanning tree of an n-vertex undirected graph. One runs on an n×n reconfigurable mesh with time complexity of O(log^2 n). The other runs with time complexity of O(log n) on an n^(1+E)×n reconfigurable mesh, where < E < 1 is a constant. All these improve the previously known results on the reconfigurable mesh. 展开更多
关键词 parallel algorithm reconfigurable mesh graph algorithm minimum spanning tree
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A Multi-Objective Optimal Evolutionary Algorithm Based on Tree-Ranking 被引量:1
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作者 Shi Chuan, Kang Li-shan, Li Yan, Yan Zhen-yuState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期207-211,共5页
Multi-objective optimal evolutionary algorithms (MOEAs) are a kind of new effective algorithms to solve Multi-objective optimal problem (MOP). Because ranking, a method which is used by most MOEAs to solve MOP, has so... Multi-objective optimal evolutionary algorithms (MOEAs) are a kind of new effective algorithms to solve Multi-objective optimal problem (MOP). Because ranking, a method which is used by most MOEAs to solve MOP, has some shortcoming s, in this paper, we proposed a new method using tree structure to express the relationship of solutions. Experiments prove that the method can reach the Pare-to front, retain the diversity of the population, and use less time. 展开更多
关键词 multi-objective optimal problem multi-objective optimal evolutionary algorithm Pareto dominance tree structure dynamic space-compressed mutative operator
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A Tree Pattern Matching Algorithm for XML Queries with Structural Preferences
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作者 Maurice Tchoupé Tchendji Lionel Tadonfouet Thomas Tébougang Tchendji 《Journal of Computer and Communications》 2019年第1期61-83,共23页
In the XML community, exact queries allow users to specify exactly what they want to check and/or retrieve in an XML document. When they are applied to a semi-structured document or to a document with an overly comple... In the XML community, exact queries allow users to specify exactly what they want to check and/or retrieve in an XML document. When they are applied to a semi-structured document or to a document with an overly complex model, the lack or the ignorance of the explicit document model (DTD—Document Type Definition, Schema, etc.) increases the risk of obtaining an empty result set when the query is too specific, or, too large result set when it is too vague (e.g. it contains wildcards such as “*”). The reason is that in both cases, users write queries according to the document model they have in mind;this can be very far from the one that can actually be extracted from the document. Opposed to exact queries, preference queries are more flexible and can be relaxed to expand the search space during their evaluations. Indeed, during their evaluation, certain constraints (the preferences they contain) can be relaxed if necessary to avoid precisely empty results;moreover, the returned answers can be filtered to retain only the best ones. This paper presents an algorithm for evaluating such queries inspired by the TreeMatch algorithm proposed by Yao et al. for exact queries. In the proposed algorithm, the best answers are obtained by using an adaptation of the Skyline operator (defined in relational databases) in the context of documents (trees) to incrementally filter into the partial solutions set, those which satisfy the maximum of preferential constraints. The only restriction imposed on documents is No-Self-Containment. 展开更多
关键词 SEMI-STRUCTURED Documents Preference QUERIES tree Pattern Matching treeMatch algorithm XML The SKYLINE Operator
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