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Cluster based hierarchical resource searching model in P2P network 被引量:1
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作者 Yang Ruijuan Liu Jian Tian Jingwen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期188-194,共7页
For the problem of large network load generated by the Gnutella resource-searching model in Peer to Peer (P2P) network, a improved model to decrease the network expense is proposed, which establishes a duster in P2P... For the problem of large network load generated by the Gnutella resource-searching model in Peer to Peer (P2P) network, a improved model to decrease the network expense is proposed, which establishes a duster in P2P network, auto-organizes logical layers, and applies a hybrid mechanism of directional searching and flooding. The performance analysis and simulation results show that the proposed hierarchical searching model has availably reduced the generated message load and that its searching-response time performance is as fairly good as that of the Gnutella model. 展开更多
关键词 Communication and information system Resource-searching model in P2P network GNUTELLA CLUSTER Hierarchical network
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Research on the User Interest Modeling of Personalized Search Engine 被引量:2
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作者 LI Zhengwei XIA Shixiong NIU Qiang XIA Zhanguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期893-896,共4页
At present, how to enable Search Engine to construct user personal interest model initially, master user's personalized information timely and provide personalized services accurately have become the hotspot in the r... At present, how to enable Search Engine to construct user personal interest model initially, master user's personalized information timely and provide personalized services accurately have become the hotspot in the research of Search Engine area. Aiming at the problems of user model's construction and combining techniques of manual customization modeling and automatic analytical modeling, a User Interest Model (UIM) is proposed in the paper. On the basis of it, the corresponding establishment and update algorithms of User lnterest Profile (UIP) are presented subsequently. Simulation tests proved that the UIM proposed and corresponding algorithms could enhance the retrieval precision effectively and have superior adaptability. 展开更多
关键词 PERSONALIZATION search Engine User Interest model intellectual agent
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Euler Characteristic Scheme of Globally Searching for Flaws in Surface Modeling
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作者 Yukun Liu Yong Yue +1 位作者 Dongwen Zhang Chunhua Li 《Advances in Pure Mathematics》 2020年第2期57-85,共29页
This paper presents a new scheme of flaw searching in surface modeling based on Euler Characteristic. This scheme can be applied to surface construction or reconstruction in computer. It is referred to as Euler Accomp... This paper presents a new scheme of flaw searching in surface modeling based on Euler Characteristic. This scheme can be applied to surface construction or reconstruction in computer. It is referred to as Euler Accompanying Test (EAT) algorithm in this paper. Two propositions in algebraic topology are presented, which are the foundation of the EAT algorithm. As the modeling is the first step for rendering in the animation and visualization, or computer-aided design (CAD) in related applications, the flaws can bring some serious problems in the final image or product, such as an artificial sense in animation rendering or a mistaken product in industry. To verify the EAT progressive procedure, a three-dimensional (3D) stamp model is constructed. The modeling process is accompanied by the EAT procedure. The EAT scheme is verified as the flaws in the stamp model are found and modified. 展开更多
关键词 ALGEBRAIC Topology EULER Characteristic FLAW searchING Surface modeling Topologic CONSISTENCE
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Algebraic or Algorithmic: Searching for Optimal Solutions in Multi-Stage Supply Chain Models
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作者 Ab Rahman Ahmad Borkistang Mohamad Sami M. Halawani 《Journal of Software Engineering and Applications》 2017年第8期663-676,共14页
In this paper we proposed an AMH Supply Chain model to obtain optimal solutions for Two-, Three- and Four-Stage for deterministic models. Besides deriving its algebraic solutions, a simple searching method is successf... In this paper we proposed an AMH Supply Chain model to obtain optimal solutions for Two-, Three- and Four-Stage for deterministic models. Besides deriving its algebraic solutions, a simple searching method is successfully applied in obtaining optimal total costs and its integer multipliers. Our model has shown promising results in comparison to Equal Cycle Time and other existing ones. The tests focused on obtaining optimal total annual costs and other related details of Two-, Three- and Four-Stage for deterministic models. The results are run under Visual Basic Programming platform using Intel? CoreTM2 Duo T6500 Processor. 展开更多
关键词 AMH model ALGEBRAIC Solution INVENTORY Coordination MULTI-STAGE Supply Chain modelS Simple search Algorithm
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基于改进POT模型的土石坝渗流监控指标拟定方法
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作者 周扬 李初寅 +1 位作者 庞锐 徐斌 《大连理工大学学报》 北大核心 2026年第1期103-110,共8页
针对现有土石坝渗流监控指标拟定方法存在主观性较强和精度较低的不足,基于智能算法改进的超阈值(peaks over threshold,POT)模型,提出了优化的土石坝渗流监控指标拟定方法.以3σ准则为确定最优阈值的理论基础,采用基于混沌映射、结合L... 针对现有土石坝渗流监控指标拟定方法存在主观性较强和精度较低的不足,基于智能算法改进的超阈值(peaks over threshold,POT)模型,提出了优化的土石坝渗流监控指标拟定方法.以3σ准则为确定最优阈值的理论基础,采用基于混沌映射、结合Levy飞行和逆向学习的动态选择策略改进的麻雀搜索算法(improved chaos sparrow search algorithm,ICSSA),对POT模型中阈值的选取方法进行优化.建立了ICSSA-POT模型,实现对监测资料尾部数据的拟合,从而得到更为合理的土石坝渗流监控指标.研究表明,相比于传统方法,所提方法可有效避免主观性与随机误差,得到的监测资料尾部数据的拟合决定系数提高了5%,具有更高的计算精度,拟定的渗流监控指标更偏于安全,对防范土石坝渗流破坏、确保土石坝安全长效运行具有较强的指导意义. 展开更多
关键词 土石坝 渗流监测 POT模型 麻雀搜索算法 参数优化
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Free Search算法率定的Sacramento模型在东北寒旱区的应用 被引量:6
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作者 王斌 黄金柏 +2 位作者 宫兴龙 朱士江 王贵作 《农业机械学报》 EI CAS CSCD 北大核心 2016年第6期171-177,共7页
采用模型对比研究方法,以萨克拉门托(Sacramento,SAC)模型为研究对象,以新安江模型为参考,采用基于动物群体的自由搜索(Free search,FS)算法作为率定水文模型的优化算法,选取松花江水系和辽河水系的3个集水区为实证流域,通过对比FS算法... 采用模型对比研究方法,以萨克拉门托(Sacramento,SAC)模型为研究对象,以新安江模型为参考,采用基于动物群体的自由搜索(Free search,FS)算法作为率定水文模型的优化算法,选取松花江水系和辽河水系的3个集水区为实证流域,通过对比FS算法率定的SAC模型和新安江模型在3个流域的模拟效果,验证SAC模型在东北寒旱区流域的适用性。研究结果表明,FS算法迭代计算过程简单,需要设置的算法参数较少,在率定SAC模型和新安江模型时效率较高;在相同的模拟条件下,FS算法率定的SAC模型模拟效果更好,其Nash模型效率系数高于新安江模型,表明SAC模型适用于东北寒旱区流域;但SAC模型在东北寒旱区的模拟精度还有待提升,模型尚需进一步发展和完善。 展开更多
关键词 Sacramento模型 新安江模型 Free search算法 东北寒旱区
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基于ElasticSearch的元数据搜索与共享平台 被引量:26
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作者 姜康 冯钧 +1 位作者 唐志贤 王超 《计算机与现代化》 2015年第2期117-121,126,共6页
随着水利行业信息化的发展,针对海量、多源、异构数据的共享与发现成为行业研究的热点。本文设计与实现一种基于Elastic Search的水利元数据搜索与共享平台,提出针对水利异构数据的解决方案并对海量数据建立索引,利用多租户访问控制策略... 随着水利行业信息化的发展,针对海量、多源、异构数据的共享与发现成为行业研究的热点。本文设计与实现一种基于Elastic Search的水利元数据搜索与共享平台,提出针对水利异构数据的解决方案并对海量数据建立索引,利用多租户访问控制策略,保证用户索引数据的一致性与安全性。通过Rest服务对索引资源进行封装,提供搜索与多粒度的共享方式。应用表明,平台能够保证用户准确高效地获得水利行业数据,节约了水利单位构建搜索系统的成本。 展开更多
关键词 元数据检索 多租户访问控制 分布式 RESTful服务 异构数据
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地下空间异构无人系统分布式协同搜索路径规划方法
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作者 詹浩 周同乐 +1 位作者 陈谋 杨家文 《哈尔滨工业大学学报》 北大核心 2026年第1期12-23,共12页
为解决地下空间中空地异构无人系统协同区域搜索效率低下的问题,本文综合考虑空中与地面障碍物的双重约束,构建了三维栅格地下空间模型。基于此,利用自适应高度的无人系统三维传感器模型,量化分析了探测距离对探测性能的影响,并采用信... 为解决地下空间中空地异构无人系统协同区域搜索效率低下的问题,本文综合考虑空中与地面障碍物的双重约束,构建了三维栅格地下空间模型。基于此,利用自适应高度的无人系统三维传感器模型,量化分析了探测距离对探测性能的影响,并采用信息素图机制,通过信息素的扩散与挥发动态更新环境信息。在分布式模型预测控制(distributed model predictive control,DMPC)框架下,融合差分变异、三角形游走、高斯扰动和t分布自适应扰动策略,提出了一种融合信息素图机制的改进人工旅鼠算法(improved artificial lemming algorithm-pheromone map,IDALA-PM),以实现多空地异构无人系统的分布式实时路径规划。仿真结果表明,所提出的IDALA-PM算法能够有效完成地下空间搜索任务,相比传统算法,搜索效率提高了54.2%。 展开更多
关键词 地下空间 空地异构无人系统 协同搜索路径规划 DMPC IDALA-PM
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Optimal search for moving targets with sensing capabilities using multiple UAVs 被引量:13
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作者 Xiaoxuan Hu Yanhong Liu Guoqiang Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期526-535,共10页
This paper studies the problem of using multiple unmanned air vehicles (UAVs) to search for moving targets with sensing capabilities. When multiple UAVs (multi-UAV) search for a number of moving targets in the mission... This paper studies the problem of using multiple unmanned air vehicles (UAVs) to search for moving targets with sensing capabilities. When multiple UAVs (multi-UAV) search for a number of moving targets in the mission area, the targets can intermittently obtain the position information of the UAVs from sensing devices, and take appropriate actions to increase the distance between themselves and the UAVs. Aiming at this problem, an environment model is established using the search map, and the updating method of the search map is extended by considering the sensing capabilities of the moving targets. A multi-UAV search path planning optimization model based on the model predictive control (MPC) method is constructed, and a hybrid particle swarm optimization algorithm with a crossover operator is designed to solve the model. Simulation results show that the proposed method can effectively improve the cooperative search efficiency and can find more targets per unit time compared with the coverage search method and the random search method. 展开更多
关键词 unmanned air vehicle (UAV) moving target search model predictive control path planning hybrid particle swarm optimization
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A Novel Search Engine for Internet of Everything Based on Dynamic Prediction 被引量:1
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作者 Hui Lu Shen Su +1 位作者 Zhihong Tian Chunsheng Zhu 《China Communications》 SCIE CSCD 2019年第3期42-52,共11页
In recent years, with the rapid development of sensing technology and deployment of various Internet of Everything devices, it becomes a crucial and practical challenge to enable real-time search queries for objects, ... In recent years, with the rapid development of sensing technology and deployment of various Internet of Everything devices, it becomes a crucial and practical challenge to enable real-time search queries for objects, data, and services in the Internet of Everything. Moreover, such efficient query processing techniques can provide strong facilitate the research on Internet of Everything security issues. By looking into the unique characteristics in the IoE application environment, such as high heterogeneity, high dynamics, and distributed, we develop a novel search engine model, and build a dynamic prediction model of the IoE sensor time series to meet the real-time requirements for the Internet of Everything search environment. We validated the accuracy and effectiveness of the dynamic prediction model using a public sensor dataset from Intel Lab. 展开更多
关键词 IoE search ENGINE IoE SECURITY real-time search model dynamic PREDICTION model time series PREDICTION
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基于SPSS Modeler质量控制关键点的监控与应用 被引量:1
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作者 蔡清秀 李超 +3 位作者 于海岐 崔福祥 李海峰 赵文涛 《鞍钢技术》 CAS 2021年第2期30-35,共6页
为了提高炼钢过程中数据查询、提取的工作效率,使用数据挖掘工具SPSS Modeler,对重点钢种生产质量关键点数据进行自动提取,并进一步处理分析和应用,不仅提高了数据的处理效率,同时利用关键点数据对现行质量控制标准进行优化,提高生产质... 为了提高炼钢过程中数据查询、提取的工作效率,使用数据挖掘工具SPSS Modeler,对重点钢种生产质量关键点数据进行自动提取,并进一步处理分析和应用,不仅提高了数据的处理效率,同时利用关键点数据对现行质量控制标准进行优化,提高生产质量管理水平。 展开更多
关键词 炼钢 数据查询 数据提取 数据挖掘 SPSS modeler 质量控制关键点
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Review on the Work of Agriculture Ontology Research Group 被引量:1
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作者 SU Xiao-lu LI Jing +2 位作者 CUI Yun-peng MENG Xian-xue WANG Yi-qian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第5期720-730,共11页
This paper introduces efforts and achievements of Agriculture Ontology Service Research Group of Agricultural Information Institute of Chinese Academy of Agriculture Sciences in last 10 years. It summarizes the resear... This paper introduces efforts and achievements of Agriculture Ontology Service Research Group of Agricultural Information Institute of Chinese Academy of Agriculture Sciences in last 10 years. It summarizes the research on ontology construction methodology, ontology management system, ontology application and etc. 展开更多
关键词 agriculture ontology service ontology search knowledge domain model ontology development
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Optimal Posture Searching Algorithm on Mobile Welding Robot 被引量:2
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作者 张涛 陈善本 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第1期84-87,共4页
An independently developed mobile welding robot system is introduced. Kinematics model is the base of robot planning. With the Denavit-Hartenberg method, robot kinematics equation can be gotten. The robot welding torc... An independently developed mobile welding robot system is introduced. Kinematics model is the base of robot planning. With the Denavit-Hartenberg method, robot kinematics equation can be gotten. The robot welding torch inclination angle consists of the working and moving angles. According to the kinematics model,both the two angles and torch position can be calculated. Under special moving angle, a two-step algorithm is used to obtain the optimal manipulator posture. The calculation result shows that the algorithm has high precision. 展开更多
关键词 mobile welding robot kinematics model posture searching algorithm
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基于Free Search的植被叶面积指数Logistic模型研究 被引量:2
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作者 朱伟峰 王斌 杨军明 《节水灌溉》 北大核心 2018年第7期94-97,103,共5页
针对利用归一化植被指数NDVI反演的植被叶面积指数LAI时间分辨率不足的问题,对传统Logistic模型进行了改进,并引入自由搜索(Free Search,FS)算法率定模型参数,建立了一种能够模拟植被逐日LAI的Logistic模型。首先,以NOAA-AVHRR提供的月N... 针对利用归一化植被指数NDVI反演的植被叶面积指数LAI时间分辨率不足的问题,对传统Logistic模型进行了改进,并引入自由搜索(Free Search,FS)算法率定模型参数,建立了一种能够模拟植被逐日LAI的Logistic模型。首先,以NOAA-AVHRR提供的月NDVI作为反演植被LAI的基础数据,采用简单生物圈模型(Si B2)反演不同土地覆被类型下的植被月LAI;其次,借鉴传统Logistic模型模拟作物干物质的思路建立了一种改进的Logistic模型,并将FS单个动物每步探查行走的位置向量作为模型参数值,利用FS的动物群体迁移行为识别改进Logistic模型的最优参数,从而研究改进Logistic模型对植被月LAI的模拟效果。呼兰河流域的应用结果表明,利用FS识别参数的改进Logistic模型对呼兰河流域6种植被的月LAI模拟效果较好,为模拟植被LAI的逐日变化过程提供了一种新方法。 展开更多
关键词 叶面积指数 土地覆被 LOGISTIC模型 自由搜索
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Scatter Search Based Particle Swarm Optimization Algorithm for Earliness/Tardiness Flowshop Scheduling with Uncertainty 被引量:2
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作者 Jia-Can Geng Zhe Cui Xing-Sheng Gu 《International Journal of Automation and computing》 EI CSCD 2016年第3期285-295,共11页
Considering the imprecise nature of the data in real-world problems, the earliness/tardiness (E/T) fiowshop scheduling problem with uncertain processing time and distinct due windows is concerned in this paper. A fu... Considering the imprecise nature of the data in real-world problems, the earliness/tardiness (E/T) fiowshop scheduling problem with uncertain processing time and distinct due windows is concerned in this paper. A fuzzy scheduling model is established and then transformed into a deterministic one by employing the method of maximizing the membership function of middle value. Moreover, an effective scatter search based particle swarm optimization (SSPSO) algorithm is proposed to minimize the sum of total earliness and tardiness penalties. The proposed SSPSO algorithm incorporates the scatter search (SS) algorithm into the frame of particle swarm optimization (PSO) algorithm and gives full play to their characteristics of fast convergence and high diversity. Besides, a differential evolution (DE) scheme is used to generate solutions in the SS. In addition, the dynamic update strategy and critical conditions are adopted to improve the performance of SSPSO. The simulation results indicate the superiority of SSPSO in terms of effectiveness and efficiency. 展开更多
关键词 Earliness/tardiness (E/T) SCHEDULING fuzzy modeling scatter search (SS) particle swarm optimization (PSO).
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Blog Opinion Retrieval with Generation Model and Mixture Model
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作者 Jie Chen Zhendong Niu +1 位作者 Xi Li Lizhe Song 《Journal of Beijing Institute of Technology》 EI CAS 2017年第3期396-403,共8页
Blog opinion retrieval aims to find blogs with opinionated information related to a given topic.Its main problem is to compute the opinion score,which balances topic relevance and opinion relevance.To deal with this p... Blog opinion retrieval aims to find blogs with opinionated information related to a given topic.Its main problem is to compute the opinion score,which balances topic relevance and opinion relevance.To deal with this problem a generative model deduced by a Bayesian approach is pro-posed,and an improved mixture model is proposed to estimate the opinion relevance between a blog and a given topic in our retrieval framework.Moreover,pointwise mutual information is used to expand sentiment words for different topics based on a general sentimental lexicon.The correlation between topic and candidate words is applied in the process of both expanding sentiment words and estimating sentence opinion scores.Experimental results show that the proposed approaches improve upon the state-of-the-art opinion retrieval method on TREC2010 dataset. 展开更多
关键词 blog opinion retrieval opinion mining blog site search hybrid model
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An approach to implementing an intelligent web search
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作者 Vitaly Klyuev 《通讯和计算机(中英文版)》 2009年第7期52-56,67,共6页
关键词 WEB 计算机网络 电子邮件 信息系统
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SNS model for providing social network channels through queries
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作者 Ilyong Shin Gunwook Lee +2 位作者 Mihyang Lee Taesup Yoon Younghwan Lim 《Journal of Measurement Science and Instrumentation》 CAS 2012年第2期173-178,共6页
Users can obtain the information through a basic web searching and find the answer to the questions directly,but maybe the expected answer does not exist.Besides,we do not know the update of new information in time.Th... Users can obtain the information through a basic web searching and find the answer to the questions directly,but maybe the expected answer does not exist.Besides,we do not know the update of new information in time.The online social networking services spread quickly and store many user data,but these data are worth less and may be unreliable answer to users’ questions.Users can obtain the simple answer but can not expect more additional information in knowledge question-answering(QA)system.In this paper,we design the system with the advantages of knowledge QA system,web searching and characteristics of social networking service for providing social network channel based on the query and answer without users’ contact network.The user can obtain real-time answers by the user network interested in users’ querires through the network channel of this system,get the additional information effectively and share it with others in the social network channel in this system. 展开更多
关键词 social networking service(SNS) model QUERY search communication channel
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动态顺序统计树类结构的函数式建模及其自动化验证 被引量:1
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作者 左正康 刘增鑫 +2 位作者 柯雨含 游珍 王昌晶 《软件学报》 北大核心 2025年第8期3531-3553,共23页
动态顺序统计树结构是一类融合了动态集合、顺序统计量以及搜索树结构特性的数据结构,支持高效的数据检索操作,广泛应用于数据库系统、内存管理和文件管理等领域.然而,当前工作侧重讨论结构不变性,如平衡性,而忽略了功能正确性的讨论.... 动态顺序统计树结构是一类融合了动态集合、顺序统计量以及搜索树结构特性的数据结构,支持高效的数据检索操作,广泛应用于数据库系统、内存管理和文件管理等领域.然而,当前工作侧重讨论结构不变性,如平衡性,而忽略了功能正确性的讨论.且现有研究方法主要针对具体的算法程序进行手工推导或交互式机械化验证,缺乏成熟且可靠的通用验证模式,自动化水平较低.为此,设计动态顺序统计搜索树类结构的Isabelle函数式建模框架和自动化验证框架,构建经过验证的通用验证引理库,可以节省开发人员验证代码的时间和成本.基于函数式建模框架,选取不平衡的二叉搜索树、平衡的二叉搜索树(以红黑树为代表)和平衡的多叉搜索树(以2−3树为代表)作为实例化的案例来展示.借助自动验证框架,多个实例化案例可自动验证,仅需要使用归纳法并调用一次auto方法或使用try命令即可,为复杂数据结构算法功能和结构正确性的自动化验证提供了参考. 展开更多
关键词 动态顺序统计树 搜索树 函数式建模 自动化验证 Isabelle定理证明器
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An Emergency Scenario Reconstruction System Based on ESMM Event Situation Model
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作者 LI Shuoming CHEN Lei +1 位作者 LIU Yu CHEN Shihong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第6期482-488,共7页
In order to keep decision-makers better informed with emergencies, it is useful to retrieve the user-oriented disaster relevant event information in an aggregated results list through meta-search engine. However, emer... In order to keep decision-makers better informed with emergencies, it is useful to retrieve the user-oriented disaster relevant event information in an aggregated results list through meta-search engine. However, emergent event is dynamic which makes it difficult to use fixed search word or word combinations. This paper proposes an event situation monitoring model(ESMM) event detection model, which realizes heuristic query word vector dynamic expanding by adopting emergency fuzzy scenario reasoning ontology cluster. Disaster event facet information automatic searching is discussed as an example in this paper. The experimental results show that the proposed method can increase accuracy and extra clues not supplied by commercial search engines, which can be used as a supplement information source for government and individuals. 展开更多
关键词 meta search event situation monitoring model(ESMM) model ONTOLOGY event scenario
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