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Orbit Weighting Scheme in the Context of Vector Space Information Retrieval
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作者 Ahmad Ababneh Yousef Sanjalawe +2 位作者 Salam Fraihat Salam Al-E’mari Hamzah Alqudah 《Computers, Materials & Continua》 SCIE EI 2024年第7期1347-1379,共33页
This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schem... This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schemes like tf-idf and BM25.These conventional methods often struggle with accurately capturing document relevance,leading to inefficiencies in both retrieval performance and index size management.OWS proposes a dynamic weighting mechanism that evaluates the significance of terms based on their orbital position within the vector space,emphasizing term relationships and distribution patterns overlooked by existing models.Our research focuses on evaluating OWS’s impact on model accuracy using Information Retrieval metrics like Recall,Precision,InterpolatedAverage Precision(IAP),andMeanAverage Precision(MAP).Additionally,we assessOWS’s effectiveness in reducing the inverted index size,crucial for model efficiency.We compare OWS-based retrieval models against others using different schemes,including tf-idf variations and BM25Delta.Results reveal OWS’s superiority,achieving a 54%Recall and 81%MAP,and a notable 38%reduction in the inverted index size.This highlights OWS’s potential in optimizing retrieval processes and underscores the need for further research in this underrepresented area to fully leverage OWS’s capabilities in information retrieval methodologies. 展开更多
关键词 information retrieval orbit weighting scheme semantic text analysis Tf-Idf weighting scheme vector space model
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Database Search Behaviors: Insight from a Survey of Information Retrieval Practices
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作者 Babita Trivedi Brijender Dahiya +2 位作者 Anjali Maan Rajesh Giri Vinod Prasad 《Intelligent Information Management》 2024年第5期195-218,共24页
This study examines the database search behaviors of individuals, focusing on gender differences and the impact of planning habits on information retrieval. Data were collected from a survey of 198 respondents, catego... This study examines the database search behaviors of individuals, focusing on gender differences and the impact of planning habits on information retrieval. Data were collected from a survey of 198 respondents, categorized by their discipline, schooling background, internet usage, and information retrieval preferences. Key findings indicate that females are more likely to plan their searches in advance and prefer structured methods of information retrieval, such as using library portals and leading university websites. Males, however, tend to use web search engines and self-archiving methods more frequently. This analysis provides valuable insights for educational institutions and libraries to optimize their resources and services based on user behavior patterns. 展开更多
关键词 information retrieval Database Search User Behavior Patterns
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Similarity matching method of power distribution system operating data based on neural information retrieval
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作者 Kai Xiao Daoxing Li +2 位作者 Pengtian Guo Xiaohui Wang Yong Chen 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期15-25,共11页
Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of dat... Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of data-driven operation management,intelligent analysis,and mining is urgently required.To investigate and explore similar regularities of the historical operating section of the power distribution system and assist the power grid in obtaining high-value historical operation,maintenance experience,and knowledge by rule and line,a neural information retrieval model with an attention mechanism is proposed based on graph data computing technology.Based on the processing flow of the operating data of the power distribution system,a technical framework of neural information retrieval is established.Combined with the natural graph characteristics of the power distribution system,a unified graph data structure and a data fusion method of data access,data complement,and multi-source data are constructed.Further,a graph node feature-embedding representation learning algorithm and a neural information retrieval algorithm model are constructed.The neural information retrieval algorithm model is trained and tested using the generated graph node feature representation vector set.The model is verified on the operating section of the power distribution system of a provincial grid area.The results show that the proposed method demonstrates high accuracy in the similarity matching of historical operation characteristics and effectively supports intelligent fault diagnosis and elimination in power distribution systems. 展开更多
关键词 Neural information retrieval Power distribution Graph data Operating section Similarity matching
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硬件损伤下IRS辅助的SWIPT系统安全波束成形设计
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作者 董洋帆 李陶深 葛志辉 《小型微型计算机系统》 CSCD 北大核心 2024年第7期1741-1748,共8页
为了提高无线携能通信(Simultaneous Wireless nformation and Power Transfer,SWIPT)通信系统的安全性,同时克服系统收发机硬件损伤(Hardware Impairments,HIs)的影响,提出一种硬件损伤下的智能反射面(Intelligent Reflecting Surface,... 为了提高无线携能通信(Simultaneous Wireless nformation and Power Transfer,SWIPT)通信系统的安全性,同时克服系统收发机硬件损伤(Hardware Impairments,HIs)的影响,提出一种硬件损伤下的智能反射面(Intelligent Reflecting Surface,IRS)辅助的SWIPT系统安全波束成形设计方法.考虑能量接收设备为潜在的窃听者,在基站最大发射功率、最小接收能量和IRS相移约束下,通过联合优化基站波束赋形矢量、人工噪声矢量和IRS的相移矩阵,构建系统安全速率最大化问题.针对该优化问题是非凸的,且优化变量是耦合的,提出一种基于交替优化和半正定松弛的有效算法来次优地解决该问题.仿真结果表明,本文所提算法能够在保障能量需求的同时,提升系统的安全性和抗硬件损伤能力. 展开更多
关键词 硬件损伤 智能反射面 无线携能通信 安全波束成形 安全速率
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复杂环境下结合EMD的GPS-IR水位反演方法 被引量:1
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作者 李玉豪 王盼 +1 位作者 张迪 唐旭 《南京信息工程大学学报》 CAS 北大核心 2024年第2期261-269,共9页
利用法国布雷斯特(Brest)港BRST测站和英国塞文大桥监测系统GNSS双频观测数据,分别在静态和高动态环境下进行GPS-IR水位反演,探究传统GNSS监测系统进行水位反演的可行性与精度.结果表明:L1波段反演精度高于L2波段;在静态场景下,GPS-IR... 利用法国布雷斯特(Brest)港BRST测站和英国塞文大桥监测系统GNSS双频观测数据,分别在静态和高动态环境下进行GPS-IR水位反演,探究传统GNSS监测系统进行水位反演的可行性与精度.结果表明:L1波段反演精度高于L2波段;在静态场景下,GPS-IR水位反演结果与验潮站数据相关系数大于0.98,在高动态场景下,桥梁GPS-IR水位反演精度稍低.利用经验模态分解(EMD)方法对算法进行改进,提高了在桥梁复杂环境下GPS-IR水位反演结果的精度,均方根误差(RMSE)相比经典方法降低约50%.本文方法提高了GPS-IR技术在不同水域环境下的适用性,在水位监测中具有很好的应用前景. 展开更多
关键词 全球定位系统干涉反射测量 信噪比 经验模态分解 水位反演
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IRS辅助大规模MIMO系统中抑制残余硬件损伤的AQBFO无源波束赋形方案
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作者 彭坤 梁彦 李飞 《数据采集与处理》 CSCD 北大核心 2024年第2期433-444,共12页
由通信收发机硬件非理想特性导致的残余硬件损伤在智能反射面(Intelligent reflecting surface,IRS)辅助的大规模多输入多输出(Multiple-input multiple-output,MIMO)系统中难以避免,并且会严重降低上行用户的可达和速率。针对这一问题... 由通信收发机硬件非理想特性导致的残余硬件损伤在智能反射面(Intelligent reflecting surface,IRS)辅助的大规模多输入多输出(Multiple-input multiple-output,MIMO)系统中难以避免,并且会严重降低上行用户的可达和速率。针对这一问题,本文提出了一种基于自适应量子菌群觅食优化(Adaptive quantum bacterial foraging optimization,AQBFO)算法的无源波束赋形方案,用于抑制残余硬件损伤对系统性能的影响。首先,基于统计信道状态信息(Channel state information,CSI)推导出系统上行可达和速率的近似解析表达式。然后,以最大化和速率为目标,基于AQBFO算法对无源波束赋形进行优化。仿真结果验证了在IRS辅助大规模MIMO系统中,基于AQBFO算法的无源波束赋形方案能够有效抑制残余硬件损伤的影响,并显著提升系统的上行遍历和速率。 展开更多
关键词 大规模多输入多输出 智能反射面 残余硬件损伤 统计信道状态信息 自适应量子菌群觅食优化
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Intelligent Reflecting Surface Assisted Transmission Optimization Strategies in Wireless Networks
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作者 He Xinxin Qi Xuan +2 位作者 Meng Wei Liu Wei Yin Changchuan 《China Communications》 SCIE CSCD 2024年第4期120-135,共16页
Wireless Power Transfer(WPT)technology can provide real-time power for many terminal devices in Internet of Things(IoT)through millimeterWave(mmWave)to support applications with large capacity and low latency.Although... Wireless Power Transfer(WPT)technology can provide real-time power for many terminal devices in Internet of Things(IoT)through millimeterWave(mmWave)to support applications with large capacity and low latency.Although the intelligent reflecting surface(IRS)can be adopted to create effective virtual links to address the mmWave blockage problem,the conventional solutions only adopt IRS in the downlink from the Base Station(BS)to the users to enhance the received signal strength.In practice,the reflection of IRS is also applicable to the uplink to improve the spectral efficiency.It is a challenging to jointly optimize IRS beamforming and system resource allocation for wireless energy acquisition and information transmission.In this paper,we first design a Low-Energy Adaptive Clustering Hierarchy(LEACH)clustering protocol for clustering and data collection.Then,the problem of maximizing the minimum system spectral efficiency is constructed by jointly optimizing the transmit power of sensor devices,the uplink and downlink transmission times,the active beamforming at the BS,and the IRS dynamic beamforming.To solve this non-convex optimization problem,we propose an alternating optimization(AO)-based joint solution algorithm.Simulation results show that the use of IRS dynamic beamforming can significantly improve the spectral efficiency of the system,and ensure the reliability of equipment communication and the sustainability of energy supply under NLOS link. 展开更多
关键词 intelligent reflecting surface(irS) joint optimization millimeter wave wireless information transmission(WIT) wireless power transfer(WPT)
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IRS增强信息与能量同传赋能物联网的鲁棒公平性资源分配算法
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作者 李世党 陈锦 +3 位作者 陈影影 龙春梅 徐劲松 李春国 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第1期129-137,共9页
针对6G物联网中信道误差影响与用户采集能量的公平性问题,该文在用户信干噪比受限、发射功率约束和反射相位模一约束的条件下,研究了智能反射面(IRS)辅助的信息与能量同传(SWIPT)系统中公平性采集能量最大化问题。为了解决该非凸问题,... 针对6G物联网中信道误差影响与用户采集能量的公平性问题,该文在用户信干噪比受限、发射功率约束和反射相位模一约束的条件下,研究了智能反射面(IRS)辅助的信息与能量同传(SWIPT)系统中公平性采集能量最大化问题。为了解决该非凸问题,分别运用Schur-Complement和S-Procedure将无限维约束转换为有限维的矩阵线性不等式,然后利用罚函数和连续凸逼近的方法将难以求解的原问题转化为标准的凸优化问题,进而提出了一种迭代的鲁棒公平性能量采集算法。数值结果表明,所提鲁棒优化算法能够明显提升网络采集的公平性能量。 展开更多
关键词 智能反射面 信息与能量同传 采集能量最大化 鲁棒优化算法
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The Preliminary Design and Implement of Plant Digital Information Retrieval System 被引量:3
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作者 樊永军 闫伟 +2 位作者 王黎元 杨秀丽 刘学威 《Agricultural Science & Technology》 CAS 2011年第5期751-755,共5页
[Objective] The aim was to set up a plant digital information retrieval system.[Method] Plant digital information retrieval system was designed by combining with Microsoft Visual Basic 6.0 Enterprise Edition database ... [Objective] The aim was to set up a plant digital information retrieval system.[Method] Plant digital information retrieval system was designed by combining with Microsoft Visual Basic 6.0 Enterprise Edition database management system and Structure Query Language.[Result] The system realized electronic management and retrieval of local plant information.The key words of retrieval included family,genus,formal name,Chinese name,Latin,morphological characteristics,habitat,collection people,collection places,and protect class and so on.[Conclusion] It provided reference for these problems of species identification and digital management of herbarium. 展开更多
关键词 Plant digital information retrieval system DATABASE Design and implement
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Query Expansion for Chinese Information Retrieval by Using a Decaying Co-occurrence Model 被引量:3
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作者 贺宏朝 何丕廉 +1 位作者 高剑峰 黄昌宁 《Transactions of Tianjin University》 EI CAS 2002年第3期183-186,共4页
Query expansion with thesaurus is one of the useful techniques in modern information retrieval (IR). In this paper, a method of query expansion for Chinese IR by using a decaying co-occurrence model is proposed and re... Query expansion with thesaurus is one of the useful techniques in modern information retrieval (IR). In this paper, a method of query expansion for Chinese IR by using a decaying co-occurrence model is proposed and realized. The model is an extension of the traditional co-occurrence model by adding a decaying factor that decreases the mutual information when the distance between the terms increases. Experimental results on TREC-9 collections show this query expansion method results in significant improvements over the IR without query expansion. 展开更多
关键词 query expansion Chinese language information retrieval
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Concept-based approach for information retrieval 被引量:1
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作者 吴晨 张全 贾宁 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期324-329,共6页
A concept-based approach is expected to resolve the word sense ambiguities in information retrieval and apply the semantic importance of the concepts, instead of the term frequency, to representing the contents of a d... A concept-based approach is expected to resolve the word sense ambiguities in information retrieval and apply the semantic importance of the concepts, instead of the term frequency, to representing the contents of a document. Consequently, a formalized document framework is proposed. The document framework is used to express the meaning of a document with the concepts which are expressed by high semantic importance. The framework consists of two parts: the "domain" information and the "situation & background" information of a document. A document-extracting algorithm and a two-stage smoothing method are also proposed. The quantification of the similarity between the query and the document framework depends on the smoothing method. The experiments on the TREC6 collection demonstrate the feasibility and effectiveness of the proposed approach in information retrieval tasks. The average recall level precision of the model using the proposed approach is about 10% higher than that of traditional ones. 展开更多
关键词 information retrieval CONCEPT semantic knowledge content representation
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Agriculture Information Retrieval System Based on Comprehensive Information Theory 被引量:7
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作者 吴启明 《Agricultural Science & Technology》 CAS 2010年第2期143-145,共3页
Through analyzing syntactic,semantic,pragmatic information,the retrieval system ACIS based on comprehensive information was established,which could achieve personalized information exaction to guide user s information... Through analyzing syntactic,semantic,pragmatic information,the retrieval system ACIS based on comprehensive information was established,which could achieve personalized information exaction to guide user s information retrieval. 展开更多
关键词 Comprehensive information theory AGRICULTURE information retrieval system
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A Multi-Tuple Rough Set Approach for Information Retrieval
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作者 马志锋 邢汉承 郑晓妹 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期63-68,共6页
How to deal with the imprecise information retrieval has become more and more important in the present information society. An efficient and effective method of information retrieval based on multi tuple rough set is... How to deal with the imprecise information retrieval has become more and more important in the present information society. An efficient and effective method of information retrieval based on multi tuple rough set is discussed in this paper. The new approach is considered as a generalization of the original rough set model for flexible information retrieval. The imprecise query results can be obtained by multi tuple approximations. 展开更多
关键词 multi tuple rough set information retrieval information system
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Web Information Retrieval的分析与展望 被引量:1
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作者 徐武 李琳 +1 位作者 陶红亮 杨印根 《景德镇高专学报》 2006年第4期15-17,共3页
网络的飞速发展使得网络信息检索成为人们迫切的需求。本文对网络信息检索技术进行了介绍、分析和比较,在此基础上,对未来的应用前景进行了展望。
关键词 网络信息检索 查准率 查全率
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An Ontology-Based Information Retrieval Model for Vegetables E-Commerce 被引量:6
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作者 TAO Teng-yang ZHAO Ming 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第5期800-807,共8页
With the rapid increment of the information on the web, traditional information retrieval based on the keywords is far from user's satisfaction in recall and precision. In order to improve the recall ratio and the pr... With the rapid increment of the information on the web, traditional information retrieval based on the keywords is far from user's satisfaction in recall and precision. In order to improve the recall ratio and the precision radio of IR engine in the vegetables e-commerce, an information retrieval model based on the vegetables e-commerce ontology is presented in this paper, vegetables e-commerce ontology was constructed by gathering and the analyzing vegetables e-commerce domain information on the web. The vegetables e-commerce ontology is composed of some kinds of vegetable classes and hierarchy relationship of vegetables classes. In the process of information retrieval, domain ontology helps to index information and information inference. An ontology-based information retrieval model is implemented, and which has more functions than the keyword-based web information retrieval engines. The experiment results show that the recall ratio and the precision ratio of ontology-based information retrieval model are higher than that of the information retrieval engine based on keyword at a certain extent. 展开更多
关键词 domain-ontology vegetables e-commerce information retrieval
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Hybrid Chinese Information Retrieval Model Based on the Combination of Keyword and Concept 被引量:2
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作者 樊孝忠 李宏乔 李良富 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期120-123,共4页
A hybrid model that is based on the Combination of keywords and concept was put forward. The hybrid model is built on vector space model and probabilistic reasoning network. It not only can exert the advantages of key... A hybrid model that is based on the Combination of keywords and concept was put forward. The hybrid model is built on vector space model and probabilistic reasoning network. It not only can exert the advantages of keywords retrieval and concept retrieval but also can compensate for their shortcomings. Their parameters can be adjusted according to different usage in order to accept the best information retrieval result, and it has been proved by our experiments. 展开更多
关键词 hybrid information retrieval model concept retrieval vector space model probabilistic reasoning network
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Research and Application on Web Information Retrieval Based on Improved FP-Growth Algorithm 被引量:2
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作者 JIAO Minghai YAN Ping JIANG Huiyan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1065-1068,共4页
A kind of single linked lists named aggregative chain is introduced to the algorithm, thus improving the architecture of FP tree. The new FP tree is a one-way tree and only the pointers that point its parent at each n... A kind of single linked lists named aggregative chain is introduced to the algorithm, thus improving the architecture of FP tree. The new FP tree is a one-way tree and only the pointers that point its parent at each node are kept. Route information of different nodes in a same item are compressed into aggregative chains so that the frequent patterns will be produced in aggregative chains without generating node links and conditional pattern bases. An example of Web key words retrieval is given to analyze and verify the frequent pattern algorithm in this paper. 展开更多
关键词 data mining CHAINS FP-growth algorithm frequent pattern aggregative information retrieval
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New Approach on the Techniques of Content-Based Image Retrieval (CBIR) Using Color, Texture and Shape Features 被引量:3
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作者 Mohd Afizi Mohd Shukran Muhamad Naim Abdullah Mohd Sidek Fadhil Mohd Yunus 《Journal of Materials Science and Chemical Engineering》 2021年第1期51-57,共7页
<div style="text-align:justify;"> Digital image collection as rapidly increased along with the development of computer network. Image retrieval system was developed purposely to provide an efficient to... <div style="text-align:justify;"> Digital image collection as rapidly increased along with the development of computer network. Image retrieval system was developed purposely to provide an efficient tool for a set of images from a collection of images in the database that matches the user’s requirements in similarity evaluations such as image content similarity, edge, and color similarity. Retrieving images based on the content which is color, texture, and shape is called content based image retrieval (CBIR). The content is actually the feature of an image and these features are extracted and used as the basis for a similarity check between images. The algorithms used to calculate the similarity between extracted features. There are two kinds of content based image retrieval which are general image retrieval and application specific image retrieval. For the general image retrieval, the goal of the query is to obtain images with the same object as the query. Such CBIR imitates web search engines for images rather than for text. For application specific, the purpose tries to match a query image to a collection of images of a specific type such as fingerprints image and x-ray. In this paper, the general architecture, various functional components, and techniques of CBIR system are discussed. CBIR techniques discussed in this paper are categorized as CBIR using color, CBIR using texture, and CBIR using shape features. This paper also describe about the comparison study about color features, texture features, shape features, and combined features (hybrid techniques) in terms of several parameters. The parameters are precision, recall and response time. </div> 展开更多
关键词 Content-Based Image retrieval Image retrieval information retrieval
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ORDINAL REGRESSION FOR INFORMATION RETRIEVAL 被引量:2
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作者 Qi Haoliang Li Sheng +2 位作者 Gao Jianfeng Han Zhongyuan Xia Xinsong 《Journal of Electronics(China)》 2008年第1期120-124,共5页
This letter presents a new discriminative model for Information Retrieval (IR), referred to as Ordinal Regression Model (ORM). ORM is different from most existing models in that it views IR as ordinal regression probl... This letter presents a new discriminative model for Information Retrieval (IR), referred to as Ordinal Regression Model (ORM). ORM is different from most existing models in that it views IR as ordinal regression problem (i.e. ranking problem) instead of binary classification. It is noted that the task of IR is to rank documents according to the user information needed, so IR can be viewed as ordinal regression problem. Two parameter learning algorithms for ORM are presented. One is a perceptron-based algorithm. The other is the ranking Support Vector Machine (SVM). The effec- tiveness of the proposed approach has been evaluated on the task of ad hoc retrieval using three English Text REtrieval Conference (TREC) sets and two Chinese TREC sets. Results show that ORM sig- nificantly outperforms the state-of-the-art language model approaches and OKAPI system in all test sets; and it is more appropriate to view IR as ordinal regression other than binary classification. 展开更多
关键词 information retrieval ir Ordinal Regression PERCEPTRON Ranking Support Vector Machine (SVM)
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Intelligent Agent-Based System for Digital Library Information Retrieval 被引量:1
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作者 师雪霖 牛振东 +1 位作者 宋瀚涛 宋丽哲 《Journal of Beijing Institute of Technology》 EI CAS 2003年第4期450-454,共5页
A new information search model is reported and the design and implementation of a system based on intelligent agent is presented. The system is an assistant information retrieval system which helps users to search wha... A new information search model is reported and the design and implementation of a system based on intelligent agent is presented. The system is an assistant information retrieval system which helps users to search what they need. The system consists of four main components: interface agent, information retrieval agent, broker agent and learning agent. They collaborate to implement system functions. The agents apply learning mechanisms based on an improved ID3 algorithm. 展开更多
关键词 intelligent agent information retrieval agent cooperation machine learning
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