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Evaluation and Selection of the Optimal Scheme of Industrial Structure Adjustment Based on DEA 被引量:1
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作者 FU Lifang GE Jiaqi MENG Jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第1期69-72,共4页
in the paper, the advanced assessment method of DEA (Date Envelopment Analysis) had been used to evaluate relative efficiency and select the optimal scheme of agricultural industrial structure adjustment. According ... in the paper, the advanced assessment method of DEA (Date Envelopment Analysis) had been used to evaluate relative efficiency and select the optimal scheme of agricultural industrial structure adjustment. According to the results of DEA models, we analyzed scale benefits of every optional schemes, probed deeply the ultimate reason for not DEA efficient, which clarified the method and approach to improve these optional schemes. Finally, a new method had been proposed to rank and select the optimal scheme. The research is significant to direct the practice of the adjustment of agricultural industrial structure. 展开更多
关键词 adjustment of industrial structure DEA efficient ranking of DMUs
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Multi-scale pore fractal characteristics of differently ranked coal and its impact on gas adsorption 被引量:5
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作者 Zhongbei Li Ting Ren +4 位作者 Xiangchun Li Ming Qiao Xiaohan Yang Lihai Tan Baisheng Nie 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第4期389-401,共13页
Well-developed pores and cracks in coal reservoirs are the main venues for gas storage and migration.To investigate the multi-scale pore fractal characteristics,six coal samples of different rankings were studied usin... Well-developed pores and cracks in coal reservoirs are the main venues for gas storage and migration.To investigate the multi-scale pore fractal characteristics,six coal samples of different rankings were studied using high-pressure mercury injection(HPMI),low-pressure nitrogen adsorption(LPGA-N2),and scanning electron microscopy(SEM)test methods.Based on the Frankel,Halsey and Hill(FHH)fractal theory,the Menger sponge model,Pores and Cracks Analysis System(PCAS),pore volume complexity(D_(v)),coal surface irregularity(Ds)and pore distribution heterogeneity(D_(p))were studied and evaluated,respectively.The effect of three fractal dimensions on the gas adsorption ability was also analyzed with high-pressure isothermal gas adsorption experiments.Results show that pore structures within these coal samples have obvious fractal characteristics.A noticeable segmentation effect appears in the Dv1and Dv2fitting process,with the boundary size ranging from 36.00 to 182.95 nm,which helps differentiate diffusion pores and seepage fractures.The D values show an asymmetric U-shaped trend as the coal metamorphism increases,demonstrating that coalification greatly affects the pore fractal dimensions.The three fractal dimensions can characterize the difference in coal microstructure and reflect their influence on gas adsorption ability.Langmuir volume(V_(L))has an evident and positive correlation with Dsvalues,whereas Langmuir pressure(P_(L))is mainly affected by the combined action of Dvand Dp.This study will provide valuable knowledge for the appraisal of coal seam gas reservoirs of differently ranked coals. 展开更多
关键词 Multi-scale pore structure Fractal theory Fractal characteristics Differently ranked coal Coalbed gas adsorption
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Evaluation Method of Web Site Structure Based on Web Structure Mining 被引量:1
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作者 Li Jun\|e 1 , Zhou Dong\|ru 2 1. Computer Center,Wuhan University, Wuhan 430072, Hubei, China 2. School of Computer,Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期791-796,共6页
The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From th... The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From the point of view of software engineering, every period in the software life must be evaluated before starting the next period's work. It is very important and essential to search relevant methods for evaluating Web structure before the site is completed. In this work, after studying the related work about the Web structure mining and analyzing the major structure mining methods (Page\|rank and Hub/Authority), a method based on the Page\|rank for Web structure evaluation in design stage is proposed. A Web structure modeling language WSML is designed, and the implement strategies for evaluating system of the Web site structure are given out. Web structure mining has being used mainly in search engines before. It is the first time to employ the Web structure mining technology to evaluate a Web structure in the design period of a Web site. It contributes to the formalization of the design documents for Web site and the improving of software engineering for large scale Web site, and the evaluating system is a practical tool for Web site construction. 展开更多
关键词 web structure mining page\|rank web structure evaluation modeling language for web structure
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Ranking all decision making units based on their elementary differences 被引量:1
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作者 Yang Feng Liang Liang Bi Gongbing Ling Liuyi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期732-740,共9页
Traditional DEA-based ranking techniques have some pitfalls such as ignoring the inherent differences among decision making units (DMUs), or lacking a common weight-based ranking, etc. To overcome these obstacles, t... Traditional DEA-based ranking techniques have some pitfalls such as ignoring the inherent differences among decision making units (DMUs), or lacking a common weight-based ranking, etc. To overcome these obstacles, the paper first examines the possible differences among all DMUs such as the technical efficiency difference, the preference structure difference and the within-group position difference. Based upon the above differences this paper induces an integrated ranking measurement which helps to give a fair and full ranking for all DMUs under evaluation. Following the three types of differences, this approach behaves greatly elaborately, accurately and reasonably. Finally, the results from the Olympics achievement evaluation approve the acceptability of this approach. 展开更多
关键词 data envelopment analysis technical efficiency preference structure within-group position cluster analysis ranking.
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System Reliability Analysis of Offshore Strctures and Component Safety Rank Assessment 被引量:1
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作者 YANG Zhiyong and XIAO Xi Lecturer, School of Naval Architecture and Ocean Engineering, Shanghai Jiaotong University (SJTU), Shanghai 200030, P. R. China. Professor, School of Naval Architecture and Ocean Engineering, SJTU, Shanghai 200030, P. R. China. 《China Ocean Engineering》 SCIE EI 1998年第2期173-181,共9页
Offshore structures will encounter serious environmental load, so it is important to study the structural system reliability and to evaluate the structural component safety rank. In this paper, the bracnch-and-bound m... Offshore structures will encounter serious environmental load, so it is important to study the structural system reliability and to evaluate the structural component safety rank. In this paper, the bracnch-and-bound method is adopted to search the main failure path, and the Ditlevsen bound method is used to calculate the system failure probability. The structure is then assessed by the fuzzy comprehensive assessment method, which evaluates the structural component safety rank. The ultimate equation of the tubular cross- section is analyzed on the basis of ultimate stregnth analysis. The influence of effect coefficients on the structural system failure probability is investigated, and basic results are obtained. A general program for spatial frame structures by means of the above method is developed, and verified by the numerical examples. 展开更多
关键词 structural system reliability branch-and-bound method fuzzy comprehensive assessment safety rank offshore structure PLATFORM
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Optimal Scheme Selection of Agricultural Production Structure Adjustment——Based on DEA Model; Punjab(Pakistan) 被引量:1
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作者 Zeeshan Ahmad Meng Jun +3 位作者 Muhammad Abdullah Mazhar Nadeem Ishaq Majid Lateef Imran Khan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第4期48-52,共5页
This paper used the modern evaluation method of DEA (Data Envelopment Analysis) to assess the comparative efficiency and then on the basis of this among multiple schemes chose the optimal scheme of agricultural prod... This paper used the modern evaluation method of DEA (Data Envelopment Analysis) to assess the comparative efficiency and then on the basis of this among multiple schemes chose the optimal scheme of agricultural production structure adjustment. Based on the results of DEA model, we dissected scale advantages of each discretionary scheme or plan. We examined scale advantages of each discretionary scheme, tested profoundly a definitive purpose behind not-DEA efficient, which elucidated the system and methodology to enhance these discretionary plans. At the end, another method had been proposed to rank and select the optimal scheme. The research was important to guide the practice if the modification of agricultural production industrial structure was carded on. 展开更多
关键词 agricultural industrial structure adjustment agricultural production structure DEA efficient DMU's ranking PUNJAB
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Damage Detection of Offshore Jacket Structures Using Frequency Domain Selective Measurements 被引量:1
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作者 M. Kianian A.A. Golafshani E. Ghodrati 《Journal of Marine Science and Application》 2013年第2期193-199,共7页
The development of damage detection techniques for offshore jacket structures is vital to prevent catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitori... The development of damage detection techniques for offshore jacket structures is vital to prevent catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitoring. In efforts to fulfill this task, concept of the minimum rank perturbation theory has been utilized. The present article introduces a promising methodology to select frequency points effectively. To achieve this goal, modal strain energy ratio of each member was evaluated at different natural frequencies of structure in order to identify the sensitive frequency domain for damage detection. The proposed methodology opens up the possibility of much greater detection efficiency. In addition, the performance of the proposed method was evaluated in relation to multiple damages. The aforementioned points are illustrated using the numerical study of a two dimensional jacket platform, and the results proved to be satisfactory utilizing the proposed methodology. 展开更多
关键词 damage detection structural health monitoring frequency response function offshore jacket platform minimum rank perturbation theory element modal strain energy ratio
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Computing Approximation GCD of Several Polynomials by Structured Total Least Norm
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作者 Xuefeng Duan Xinjun Zhang Qingwen Wang 《Advances in Linear Algebra & Matrix Theory》 2013年第4期39-46,共8页
The task of determining the greatest common divisors (GCD) for several polynomials which arises in image compression, computer algebra and speech encoding can be formulated as a low rank approximation problem with Syl... The task of determining the greatest common divisors (GCD) for several polynomials which arises in image compression, computer algebra and speech encoding can be formulated as a low rank approximation problem with Sylvester matrix. This paper demonstrates a method based on structured total least norm (STLN) algorithm for matrices with Sylvester structure. We demonstrate the algorithm to compute an approximate GCD. Both the theoretical analysis and the computational results show that the method is feasible. 展开更多
关键词 SYLVESTER Matrix Approximate GREATEST Common DIVISOR Low rank APPROXIMATION structureD TOTAL Least Norm Numerical Method
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Probability Distribution of Edge in Adjacent Matrix of Aviation Network of China and Algorithm of Searching Non-overlap Community Structure Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Wei Chong 《Journal of Traffic and Transportation Engineering》 2021年第1期1-7,共7页
In order to discover the probability distribution feature of edge in aviation network adjacent matrix of China and on the basis of this feature to establish an algorithm of searching non-overlap community structure in... In order to discover the probability distribution feature of edge in aviation network adjacent matrix of China and on the basis of this feature to establish an algorithm of searching non-overlap community structure in network to reveal the inner principle of complex network with the feature of small world in aspect of adjacent matrix and community structure,aviation network adjacent matrix of China was transformed according to the node rank and the matrix was arranged on the basis of ascending node rank with the center point as original point.Adjacent probability from the original point to extension around in approximate area was calculated.Through fitting probability distribution curve,power function of probability distribution of edge in adjacent matrix arranged by ascending node rank was found.According to the feature of adjacent probability distribution,deleting step by step with node rank ascending algorithm was set up to search non-overlap community structure in network and the flow chart of algorithm was given.A non-overlap community structure with 10 different scale communities in aviation network of China was found by the computer program written on the basis of this algorithm. 展开更多
关键词 Air transportation adjacent matrix deleting step by step with node rank ascending algorithm aviation network of China network community structure
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Numerical Computation of Structured Singular Values for Companion Matrices
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作者 Mutti-Ur Rehman Shabana Tabassum 《Journal of Applied Mathematics and Physics》 2017年第5期1057-1072,共16页
In this article, the computation of μ-values known as Structured Singular Values SSV for the companion matrices is presented. The comparison of lower bounds with the well-known MATLAB routine mussv is investigated. T... In this article, the computation of μ-values known as Structured Singular Values SSV for the companion matrices is presented. The comparison of lower bounds with the well-known MATLAB routine mussv is investigated. The Structured Singular Values provides important tools to analyze the stability and instability analysis of closed loop time invariant systems in the linear control theory as well as in structured eigenvalue perturbation theory. 展开更多
关键词 structureD SINGULAR Value Block DIAGONAL MATRICES Spectral RADIUS Low-rank Approximation
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An efficient block variant of robust structured multifrontal factorization method
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作者 左宪禹 莫则尧 谷同祥 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期225-232,共8页
Based on the two-dimensional three-temperature (2D3T) radiation diffusion equations and its discrete system, using the block diagonal structure of the three-temperature matrix, the reordering and symbolic decomposit... Based on the two-dimensional three-temperature (2D3T) radiation diffusion equations and its discrete system, using the block diagonal structure of the three-temperature matrix, the reordering and symbolic decomposition parts of the RSMF method are replaced with corresponding block operation in order to improve the solution efficiency. We call this block form method block RSMF (in brief, BRSMF) method. The new BRSMF method not only makes the reordering and symbolic decomposition become more effective, but also keeps the cost of numerical factorization from increasing and ensures the precision of solution very well. The theoretical analysis of the computation complexity about the new BRSMF method shows that the solution efficiency about the BRSMF method is higher than the original RSMF method. The numerical experiments also show that the new BRSMF method is more effective than the original RSMF method. 展开更多
关键词 HSS structure low-rank property multifrontal method two-dimensional three-temperature radia-tive diffusion equations
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Filtering algorithm of line structured light for long-distance obstacle detection
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作者 邵海燕 张振海 李科杰 《Journal of Beijing Institute of Technology》 EI CAS 2016年第4期521-525,共5页
Since unmanned ground vehicles often encounter concave and convex obstacles in wild ground, a filtering algorithm using line structured light to detect these long distance obstacles is proposed. For the line structure... Since unmanned ground vehicles often encounter concave and convex obstacles in wild ground, a filtering algorithm using line structured light to detect these long distance obstacles is proposed. For the line structured light image, a ranked-order based adaptively extremum median (RAEM) filter algorithm on salt and pepper noise is presented. In the algorithm, firstly effective points and noise points in a filtering window are differentiated; then the gray values of noise points are replaced by the medium of gray values of the effective pixels, with the efficient points' gray values unchanged; in the end this algorithm is proved to be efficient by experiments. Experimental resuits demonstrate that the image blur, resulting into proposed algorithm can remove noise points effectively and minimize the protecting the edge information as much as possible. 展开更多
关键词 unmanned ground vehicles line structured light concave and convex obstacles detec-tion ranked-order based adaptively extremum median (RAEM) filter filter algorithm
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世界一流大学结构特征与功能表现的关系研究--基于THE世界大学排名2019年数据的分析 被引量:5
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作者 张妍 《黑龙江高教研究》 北大核心 2020年第3期45-50,共6页
建设世界一流大学是提升国家核心竞争力的重要举措,是我国高等教育发展的重要战略。通过对"学生规模、生师比、研究生比例和留学生比例"等四个大学结构维度的分类,基于THE世界大学排名2019年数据,比较分析不同结构类型世界一... 建设世界一流大学是提升国家核心竞争力的重要举措,是我国高等教育发展的重要战略。通过对"学生规模、生师比、研究生比例和留学生比例"等四个大学结构维度的分类,基于THE世界大学排名2019年数据,比较分析不同结构类型世界一流大学在"人才培养、科学研究、社会服务和国际化"等四个大学功能维度上的差距。研究发现,具备"小型学生规模、大生师比、中研究生比例和高留学生比例"结构特征的世界一流大学在其大学整体功能发挥方面表现更佳。 展开更多
关键词 世界一流大学 大学结构 大学功能 the世界大学排名
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Fuzzy Earthwork Dynamic Allocation and Optimization for Construction of High Concrete Face Rockfill Dam 被引量:2
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作者 刘宁 崔博 钟登华 《Transactions of Tianjin University》 EI CAS 2012年第6期426-431,共6页
Due to the complexity of earthwork allocation system for the construction of high concrete face rockfill dam,traditional allocation and planning are not able to function properly in the construction process with stron... Due to the complexity of earthwork allocation system for the construction of high concrete face rockfill dam,traditional allocation and planning are not able to function properly in the construction process with strong randomness.In this paper,the working mechanism of earthwork dynamic allocation system is analyzed comprehensively and a solution to fuzzy earthwork dynamic allocation is proposed on the basis of uncertain factors in the earthwork allocation of a hydropower project.Under the premise of actual situation and the experience of the construction site,an all-coefficient-fuzzy linear programming mathematical model with fuzzy parameters and constraints for earthwork allocation is established according to the structure unit weighted ranking criteria.In this way,the deficiency of certain allocation model can be overcome.The application results indicate that the proposed method is more rational compared with traditional earthwork allocation. 展开更多
关键词 high concrete face rockfill dam fuzzy number earthwork dynamic allocation structure unit weighted ranking
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Answer Ranking with Discourse Structure Feature 被引量:1
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作者 Mao Cunli Chen Fangqiong +2 位作者 Yu Zhengtao Guo Jianyi Zong Huanyun 《China Communications》 SCIE CSCD 2012年第3期110-123,共14页
For the complex questions of Chinese question answering system, we propose an answer extraction method with discourse structure feature combination. This method uses the relevance of questions and answers to learn to ... For the complex questions of Chinese question answering system, we propose an answer extraction method with discourse structure feature combination. This method uses the relevance of questions and answers to learn to rank the answers. Firstly, the method analyses questions to generate the query string, and then submits the query string to search engines to retrieve relevant documents. Sec- ondly, the method makes retrieved documents seg- mentation and identifies the most relevant candidate answers, in addition, it uses the rhetorical relations of rhetorical structure theory to analyze the relationship to determine the inherent relationship between para- graphs or sentences and generate the answer candi- date paragraphs or sentences. Thirdly, we construct the answer ranking model,, and extract five feature groups and adopt Ranking Support Vector Machine (SVM) algorithm to train ranking model. Finally, it re-ranks the answers with the training model and fred the optimal answers. Experiments show that the proposed method combined with discourse structure features can effectively improve the answer extrac- ting accuracy and the quality of non-factoid an- swers. The Mean Reciprocal Rank (MRR) of the an- swer extraction reaches 69.53%. 展开更多
关键词 complex questions discourse structure learning to rank answer extracting
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基于PROMETHEE-2TUPLE群决策的信息外包商选择
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作者 彭杰 梁志杰 《西部论坛》 2010年第3期100-105,共6页
在信息不对称的复杂竞争环境下,中小企业的IT外包商选择是一个很复杂的过程,很难对模糊性和不确定的因素进行量化。通过构建中小企业IT外包商的决策模型,采用数值、区间数、语义三种异值评判信息对评估准则进行刻画,可以为中小企业信息... 在信息不对称的复杂竞争环境下,中小企业的IT外包商选择是一个很复杂的过程,很难对模糊性和不确定的因素进行量化。通过构建中小企业IT外包商的决策模型,采用数值、区间数、语义三种异值评判信息对评估准则进行刻画,可以为中小企业信息系统外包决策提供合理指导;其中,运用二元语义及其集结运算算子进行语言评价信息的处理,有效避免了以往采用的语言信息处理方法所产生的信息损失和扭曲,保持了信息的完整性。 展开更多
关键词 IT外包 外包商选择 偏好顺序结构评估法 二元语义 群决策
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RGBD Salient Object Detection by Structured Low-Rank Matrix Recovery and Laplacian Constraint 被引量:1
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作者 Chang Tang Chunping Hou 《Transactions of Tianjin University》 EI CAS 2017年第2期176-183,共8页
A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the s... A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the sparsity term. Secondly, the depth information is fused into the model by a Laplacian regularization term to ensure that the image regions which share similar depth value will be allocated to similar saliency value. Thirdly, a variation of alternating direction method is proposed to solve the proposed model. Finally, both quantitative and qualitative experimental results on NLPR1000 and NJU400 show the advantage of the proposed RGBD salient object detection model. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Laplace transforms Object recognition RECOVERY
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一种有效的本体排序算法MIDSRank 被引量:5
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作者 张志强 宋伟涛 谢晓芹 《计算机研究与发展》 EI CSCD 北大核心 2011年第6期1077-1088,共12页
本体已经在很多的领域中得到了广泛的应用,网络上的本体也越来越多,为了节约本体构建的成本避免从头构建本体,人们经常首先从网络上获取候选者,然后再以此为基础构建自己的本体.而随之而来的本体排序问题则成为一个研究热点.通过对现有... 本体已经在很多的领域中得到了广泛的应用,网络上的本体也越来越多,为了节约本体构建的成本避免从头构建本体,人们经常首先从网络上获取候选者,然后再以此为基础构建自己的本体.而随之而来的本体排序问题则成为一个研究热点.通过对现有本体排序算法的总结与分析,将现有本体排序算法划分为两大类,分别阐述了其基本思想以及存在的问题.然后,提出了一种经过改进的本体排序方法,该方法结合了原有方法的优点并提高了本体搜索的质量.最后讨论了未来研究的方向和注意事项. 展开更多
关键词 本体 本体排序 概念结构 连接分析 内容
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基于PageRank算法的权威值不均衡分配问题 被引量:20
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作者 田甜 倪林 《计算机工程》 CAS CSCD 北大核心 2007年第18期53-55,共3页
PageRank对所链接的网页的"权威值"存在平均分配的思想,由于互联网的网页是千差万别的,因此这种方法存在一定的局限性。该文利用了Web链接结构,提出了一种权威值不均衡分配的方法(IPR),通过与PageRank算法相比,IPR的排序结果... PageRank对所链接的网页的"权威值"存在平均分配的思想,由于互联网的网页是千差万别的,因此这种方法存在一定的局限性。该文利用了Web链接结构,提出了一种权威值不均衡分配的方法(IPR),通过与PageRank算法相比,IPR的排序结果比PageRank提高了近90%的相关度。 展开更多
关键词 网页结构挖掘 网页排序 改进的Pagerank
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基于网页链接与用户反馈的PageRank算法改进研究 被引量:13
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作者 曹姗姗 王冲 《计算机科学》 CSCD 北大核心 2014年第12期179-182,共4页
在网页链接结构的排序算法PageRank的基础上,提出了一种改进的Bias PageRank(BPR)算法。为了提高用户对网页排序结果的满意度,该算法结合网页链接结构与用户反馈信息(点击率、最近一次点击时间等)进行综合分析,从而从网页设计与用户角... 在网页链接结构的排序算法PageRank的基础上,提出了一种改进的Bias PageRank(BPR)算法。为了提高用户对网页排序结果的满意度,该算法结合网页链接结构与用户反馈信息(点击率、最近一次点击时间等)进行综合分析,从而从网页设计与用户角度共同对网页PR值进行合理分配,以在一定程度上达到高质量网页尽量排序靠前、信息价值低的网页尽量下沉的目的。仿真实验表明,BPR算法在一定程度上改善了排序效果,提升了用户信息检索满意度。 展开更多
关键词 网页排序 链接结构 用户反馈 PAGErank 算法改进
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