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Meta-analysis of potentially confounding effect of class size on associations between object-oriented metrics and maintainability
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作者 卢红敏 周毓明 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期281-283,共3页
This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented(OO)metrics and maintainability... This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented(OO)metrics and maintainability.To draw as many general conclusions as possible,the confounding effect of class size is analyzed on 127 C++ systems and 113 Java systems.For each OO metric,the indirect effect that represents the distortion of the association caused by class size and its variance for individual systems is first computed.Then,a statistical meta-analysis technique is used to compute the average indirect effect over all the systems and to determine if it is significantly different from zero.The experimental results show that the confounding effects of class size on the associations between OO metrics and maintainability generally exist,regardless of whatever size metric is used.Therefore,empirical studies validating OO metrics on maintainability should consider class size as a confounding variable. 展开更多
关键词 object-oriented metrics VALIDATION class size CONFOUNDING MAINTAINABILITY
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Flood predictions from metrics to classes by multiple machine learning algorithms coupling with clustering-deduced membership degree
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作者 ZHAI Xiaoyan ZHANG Yongyong +5 位作者 XIA Jun ZHANG Yongqiang TANG Qiuhong SHAO Quanxi CHEN Junxu ZHANG Fan 《Journal of Geographical Sciences》 2026年第1期149-176,共28页
Accurate prediction of flood events is important for flood control and risk management.Machine learning techniques contributed greatly to advances in flood predictions,and existing studies mainly focused on predicting... Accurate prediction of flood events is important for flood control and risk management.Machine learning techniques contributed greatly to advances in flood predictions,and existing studies mainly focused on predicting flood resource variables using single or hybrid machine learning techniques.However,class-based flood predictions have rarely been investigated,which can aid in quickly diagnosing comprehensive flood characteristics and proposing targeted management strategies.This study proposed a prediction approach of flood regime metrics and event classes coupling machine learning algorithms with clustering-deduced membership degrees.Five algorithms were adopted for this exploration.Results showed that the class membership degrees accurately determined event classes with class hit rates up to 100%,compared with the four classes clustered from nine regime metrics.The nonlinear algorithms(Multiple Linear Regression,Random Forest,and least squares-Support Vector Machine)outperformed the linear techniques(Multiple Linear Regression and Stepwise Regression)in predicting flood regime metrics.The proposed approach well predicted flood event classes with average class hit rates of 66.0%-85.4%and 47.2%-76.0%in calibration and validation periods,respectively,particularly for the slow and late flood events.The predictive capability of the proposed prediction approach for flood regime metrics and classes was considerably stronger than that of hydrological modeling approach. 展开更多
关键词 flood regime metrics class prediction machine learning algorithms hydrological model
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Detecting Design Patterns in Object-Oriented Program Source Code by Using Metrics and Machine Learning 被引量:4
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作者 Satoru Uchiyama Atsuto Kubo +1 位作者 Hironori Washizaki Yoshiaki Fukazawa 《Journal of Software Engineering and Applications》 2014年第12期983-998,共16页
Detecting well-known design patterns in object-oriented program source code can help maintainers understand the design of a program. Through the detection, the understandability, maintainability, and reusability of ob... Detecting well-known design patterns in object-oriented program source code can help maintainers understand the design of a program. Through the detection, the understandability, maintainability, and reusability of object-oriented programs can be improved. There are automated detection techniques;however, many existing techniques are based on static analysis and use strict conditions composed on class structure data. Hence, it is difficult for them to detect and distinguish design patterns in which the class structures are similar. Moreover, it is difficult for them to deal with diversity in design pattern applications. To solve these problems in existing techniques, we propose a design pattern detection technique using source code metrics and machine learning. Our technique judges candidates for the roles that compose design patterns by using machine learning and measurements of several metrics, and it detects design patterns by analyzing the relations between candidates. It suppresses false negatives and distinguishes patterns in which the class structures are similar. As a result of experimental evaluations with a set of programs, we confirmed that our technique is more accurate than two conventional techniques. 展开更多
关键词 Design PATTERNS SOFTWARE metrics MACHINE LEARNING object-oriented PROGRAMMING SOFTWARE Maintenance
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Empirical Analysis of Object-Oriented Design Metrics for Predicting Unit Testing Effort of Classes
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作者 Mourad Badri Fadel Toure 《Journal of Software Engineering and Applications》 2012年第7期513-526,共14页
In this paper, we investigate empirically the relationship between object-oriented design metrics and testability of classes. We address testability from the point of view of unit testing effort. We collected data fro... In this paper, we investigate empirically the relationship between object-oriented design metrics and testability of classes. We address testability from the point of view of unit testing effort. We collected data from three open source Java software systems for which JUnit test cases exist. To capture the testing effort of classes, we used metrics to quantify the corresponding JUnit test cases. Classes were classified, according to the required unit testing effort, in two categories: high and low. In order to evaluate the relationship between object-oriented design metrics and unit testing effort of classes, we used logistic regression methods. We used the univariate logistic regression analysis to evaluate the individual effect of each metric on the unit testing effort of classes. The multivariate logistic regression analysis was used to explore the combined effect of the metrics. The performance of the prediction models was evaluated using Receiver Operating Characteristic analysis. The results indicate that: 1) complexity, size, cohesion and (to some extent) coupling were found significant predictors of the unit testing effort of classes and 2) multivariate regression models based on object-oriented design metrics are able to accurately predict the unit testing effort of classes. 展开更多
关键词 Software TESTABILITY Unit TESTING TESTING EFFORT metrics RELATIONSHIP Prediction and Empirical Analysis
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A Survey on the Existence of Harmonic Metrics on Vector Bundles
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作者 SHEN Zhenghan ZHANG Xi 《数学进展》 北大核心 2025年第2期390-404,共15页
In this paper,we give a survey on the existence of Hermitian-Einstein metrics and harmonic metrics.
关键词 Hermitian-Einstein metric harmonic metric holomorphic vector bundle non-Hermitian Yang-Mills bundle
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Some analytic results and applications in extremal Hermitian metrics
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作者 SANG Haoxin WU Yingyi 《中国科学院大学学报(中英文)》 北大核心 2025年第5期589-599,共11页
In this paper,we introduce and prove three analytic results related to uniform convergence,properties of Newtonian potential,and convergence of sequences in Sobolev space constrained by their Laplacian.Then,utilizing ... In this paper,we introduce and prove three analytic results related to uniform convergence,properties of Newtonian potential,and convergence of sequences in Sobolev space constrained by their Laplacian.Then,utilizing our analytic results,we develop a complete proof of a crucial estimate appearing in the results of Guofang Wang and Xiaohua Zhu,which states the classification of extremal Hermitian metrics with finite energy and area on compact Riemann surfaces and finite singularities satisfying small singular angles. 展开更多
关键词 extremal Hermitian metrics conical singularities of metrics Newtonian potential
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Data-driven distributionally robust Kelly portfolio optimization based on coherent Wasserstein metrics
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作者 Yimeng Sun Zhenfeng Zou 《中国科学技术大学学报》 北大核心 2025年第8期48-58,I0002,共12页
The Kelly strategy is a common approach in portfolio optimization problems that aims to maximize the expected portfolio growth rate in the long term.Its computation requires complete knowledge of the asset return dist... The Kelly strategy is a common approach in portfolio optimization problems that aims to maximize the expected portfolio growth rate in the long term.Its computation requires complete knowledge of the asset return distribution,which is obviously not observable,but can be inferred from sample data.Motivated by recent developments in data-driven optimization methods,we propose a new class of coherent Wasserstein data-driven Kelly portfolio optimization models.In particular,we establish a class of ambiguity sets based on coherent Wasserstein metrics,and these new metrics can strike a good balance between robustness and data-drivenness,thus providing richer choices for ambiguity set design.The Kelly portfolio optimization model,which is data-driven and based on coherent Wasserstein balls,can be solved efficiently as a finite-dimensional convex program.This model also provides a robust data-driven solution.In addition,we numerically investigate the proposed model and find that it outperforms the type-1 Wasserstein-Kelly portfolio,especially the classical Kelly portfolio.Moreover,it indicates that we can obtain a portfolio with higher final value and stability,especially in controlling volatility and maximum drawdown. 展开更多
关键词 distributionally robust optimization Kelly strategy coherent Wasserstein metrics
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The Gravitational Potential and the Gravitational Force According to the Correct Reissner-Nordstrøm, Kerr and Kerr-Newman Metrics
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作者 Carlo Maria Pace 《Journal of Modern Physics》 2025年第1期52-92,共41页
In a recent article, we have corrected the traditional derivation of the Schwarzschild metric, thus obtaining the formulation of the correct Schwarzschild metric, which is different from the traditional Schwarzschild ... In a recent article, we have corrected the traditional derivation of the Schwarzschild metric, thus obtaining the formulation of the correct Schwarzschild metric, which is different from the traditional Schwarzschild metric. Then, in another article by starting from this correct Schwarzschild metric, we have corrected also the Reissner-Nordstrøm, Kerr and Kerr-Newman metrics. On the other hand, in a third article, always by starting from this correct Schwarzschild metric, we have obtained the formulas of the correct gravitational potential and of the correct gravitational force in the case described by this metric. Now, in this article, by starting from these correct Reissner-Nordstrøm, Kerr and Kerr-Newman metrics and proceeding in a manner analogous to this third article, we obtain the formulas of the correct gravitational potential and of the correct gravitational force in the cases described by these metrics. Moreover, we analyze these correct results and their consequences. Finally, we propose some possible crucial experiments between the commonly accepted theory and the same theory corrected according to this article. 展开更多
关键词 General Theory of Relativity SCHWARZSCHILD Reissner-Nordstrøm KERR Kerr-Newman metric Gravitational Potential Gravitational Force Orbital Motion
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EXISTENCE OF SOME SPECIAL CONFORMALLY-KAHLER METRICS ON CERTAIN CP1 BUNDLES
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作者 Jing CHEN Daniel GUAN 《Acta Mathematica Scientia》 2025年第2期525-539,共15页
In this paper,we prove that for certain fiber bundles there is a k-Futaki-Ono conformally Kahler metric related to a metric in any given Kahler class for any k≥2.
关键词 Hermitian metrics conformally-Kahler metrics complex manifolds scalar curvature fiber bundle almost homogeneous manifolds
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X-OODM:Leveraging Explainable Object-Oriented Design Methodology for Multi-Domain Sentiment Analysis
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作者 Abqa Javed Muhammad Shoaib +2 位作者 Abdul Jaleel Mohamed Deriche Sharjeel Nawaz 《Computers, Materials & Continua》 2025年第3期4977-4994,共18页
Incorporation of explainability features in the decision-making web-based systems is considered a primary concern to enhance accountability,transparency,and trust in the community.Multi-domain Sentiment Analysis is a ... Incorporation of explainability features in the decision-making web-based systems is considered a primary concern to enhance accountability,transparency,and trust in the community.Multi-domain Sentiment Analysis is a significant web-based system where the explainability feature is essential for achieving user satisfaction.Conventional design methodologies such as object-oriented design methodology(OODM)have been proposed for web-based application development,which facilitates code reuse,quantification,and security at the design level.However,OODM did not provide the feature of explainability in web-based decision-making systems.X-OODM modifies the OODM with added explainable models to introduce the explainability feature for such systems.This research introduces an explainable model leveraging X-OODM for designing transparent applications for multidomain sentiment analysis.The proposed design is evaluated using the design quality metrics defined for the evaluation of the X-OODM explainable model under user context.The design quality metrics,transferability,simulatability,informativeness,and decomposability were introduced one after another over time to the evaluation of the X-OODM user context.Auxiliary metrics of accessibility and algorithmic transparency were added to increase the degree of explainability for the design.The study results reveal that introducing such explainability parameters with X-OODM appropriately increases system transparency,trustworthiness,and user understanding.The experimental results validate the enhancement of decision-making for multi-domain sentiment analysis with integration at the design level of explainability.Future work can be built in this direction by extending this work to apply the proposed X-OODM framework over different datasets and sentiment analysis applications to further scrutinize its effectiveness in real-world scenarios. 展开更多
关键词 Measurable explainable web-based application object-oriented design sentiment analysis MULTI-DOMAIN
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Distributional scalar curvature and Einstein metrics
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作者 ZHANG Huai-yu ZHANG Jiang-wei 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期458-479,共22页
In this paper,we study scalar curvature rigidity of non-smooth metrics on smooth manifolds with non-positive Yamabe invariant.We prove that if the scalar curvature is not less than the Yamabe invariant in the distribu... In this paper,we study scalar curvature rigidity of non-smooth metrics on smooth manifolds with non-positive Yamabe invariant.We prove that if the scalar curvature is not less than the Yamabe invariant in the distributional sense,then the manifold must be isometric to an Einstein manifold.This result extends Theorem 1.4 in Jiang,Sheng and Zhang[27],from a special case where the manifolds have zero Yamabe invariant to general cases where the manifolds have non-positive Yamabe invariant. 展开更多
关键词 scalar curvature Einstein metric Yamabe invariant
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Petroleum Exploration and Development ranks top in core evaluation metrics among Chinese scientific and technical journals
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作者 Editorial Office of Petroleum Exploration and Development 《Petroleum Exploration and Development》 2025年第6期F0002-F0002,共1页
According to the 2025 edition of Chinese Science and Technology Journal Citation Reports(Core Edition)released by the Institute of Scientific and Technical Information of China,Petroleum Exploration and Development ac... According to the 2025 edition of Chinese Science and Technology Journal Citation Reports(Core Edition)released by the Institute of Scientific and Technical Information of China,Petroleum Exploration and Development achieved a core impact factor of 6.246 in 2024.It ranked 2nd among 2,202 core journals of natural sciences and 1st among 41 journals in the petroleum and natural gas engineering category,with a total core citation frequency of 7,502. 展开更多
关键词 chinese scientific technical journals exploration development development natural sciences chinese science technology journal citation reports institute scientific technical information china core evaluation metrics petroleum exploration
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美国STAR METRICS项目及其对我国科技评价的启示 被引量:13
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作者 杨国梁 肖小溪 李晓轩 《科学学与科学技术管理》 CSSCI 北大核心 2011年第12期12-17,25,共7页
联邦政府投资于科学,其产生的益处或者价值是什么?这是一个社会各界普遍关注的问题。2008年全球金融危机爆发之后,奥巴马政府出台了总额为7 870亿美元的一揽子刺激经济复苏方案,其中76亿美元被直接用于科学研究。为了向公众展示科学研... 联邦政府投资于科学,其产生的益处或者价值是什么?这是一个社会各界普遍关注的问题。2008年全球金融危机爆发之后,奥巴马政府出台了总额为7 870亿美元的一揽子刺激经济复苏方案,其中76亿美元被直接用于科学研究。为了向公众展示科学研究资金如何对美国经济社会产生影响,美国政府提出了STAR METRICS项目,旨在通过联邦政府和研究机构之间的合作,创建跨部门共享的数据库以及数据展示工具,从而对联邦R&D投入的影响进行评价。对STAR METRICS项目的情况进行了深入地调研和分析,并在此基础上提出对我国科技评价的若干思考。 展开更多
关键词 科技评价 R&D投入 STAR metrics
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Effect of slice scope on data slice-based class cohesion metrics 被引量:3
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作者 周毓明 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期174-177,共4页
This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are c... This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope. 展开更多
关键词 COHESION class data slice metrics object-oriented
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电子资源使用评估与E-Metrics 被引量:13
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作者 张玲 孙坦 《图书馆杂志》 CSSCI 北大核心 2005年第3期24-27,共4页
E-Metrics 项目是美国研究图书馆协会新评估计划的5个子项目之一。本文对E-Metrics 项目的产生背景及发展历程进行较为详细的介绍,并对整个项目进行简要的评价。
关键词 E—metrics项目 图书馆 电子资源 网络环境
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Altmetrics在论文影响力评价中的应用研究 被引量:10
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作者 赵蓉英 张扬 陈婧 《情报科学》 CSSCI 北大核心 2018年第6期3-8,39,共7页
【目的/意义】综合国内外对Altmetrics研究的相关论文,介绍了Altmetrics的定义、产生和发展过程,指出Altmetrics与传统计量学的联系与区别,着重分析了Altmetrics服务提供平台、Altmetrics计量指标及工具应用研究现状。【方法/过程】针... 【目的/意义】综合国内外对Altmetrics研究的相关论文,介绍了Altmetrics的定义、产生和发展过程,指出Altmetrics与传统计量学的联系与区别,着重分析了Altmetrics服务提供平台、Altmetrics计量指标及工具应用研究现状。【方法/过程】针对目前国内外学者关于Altmetrics指标研究的疑问,以PLOS ONE为例选取图书情报领域论文进行浏览量与被引量的相关性分析。【结果/结论】得出了PLOS ONE相应计量指标能够有效指示高被引文献的结论。证明了Altmetrics能够有效体现文献学术影响力以及社会影响力。最后正对Altmetrics研究现状进行了表达了自己的见解,指出后续可能的研究方向和待解决的问题。 展开更多
关键词 Altmetrics 评价指标 计量工具 PLOS ONE
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STAR METRICS__美国色彩浓厚的科技评价框架 被引量:2
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作者 李攀 雷二庆 《科研管理》 CSSCI 北大核心 2015年第S1期390-395,共6页
为向公众展示联邦政府科学投入产生的成效和影响,美国提出并实施了STAR METRICS项目,旨在研发一种基于测度的评价框架,用以评价美国联邦政府R&D投资的效益,从而促进政策制定、明确责任、提高公众参与度。2013年7月,兰德公司在"... 为向公众展示联邦政府科学投入产生的成效和影响,美国提出并实施了STAR METRICS项目,旨在研发一种基于测度的评价框架,用以评价美国联邦政府R&D投资的效益,从而促进政策制定、明确责任、提高公众参与度。2013年7月,兰德公司在"如何测量科研工作:框架与方法指南"的研究报告中,讨论了包括STAR METRICS在内的全球14个评价框架。本文基于该报告内容及相关资料,着重概括了STAR METRICS评价框架的应用情况和发展前景,并提出了对我国科技评价的几点启示。总体来看,该框架突出的特点是强调自由、强调实用,具有浓厚的美国文化色彩。 展开更多
关键词 STAR metrics 评价框架 兰德公司
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基于Credit Metrics的城投公司结构性风险评价研究 被引量:2
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作者 孙慧 高磊 《兰州交通大学学报》 CAS 2014年第6期82-87,共6页
随着我国城市基础设施建设规模的快速扩大,城市基础设施建设投资公司项目类型多元化与融资方式多元化匹配造成的结构性风险已经成为影响其健康发展的主要问题.在分析了城投公司结构性风险的发生机理及传导机制的基础上,针对城投公司债... 随着我国城市基础设施建设规模的快速扩大,城市基础设施建设投资公司项目类型多元化与融资方式多元化匹配造成的结构性风险已经成为影响其健康发展的主要问题.在分析了城投公司结构性风险的发生机理及传导机制的基础上,针对城投公司债务的信用转移问题,运用Credit Metrics模型对城投公司结构性风险进行评价研究.结果表明,城投公司存在结构性风险且隐患巨大.一旦资金链出现问题,城投公司的债务将出现严重的违约情况. 展开更多
关键词 城投公司 结构性风险 CREDIT metrics VAR
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Google Scholar Metrics、Web of Science和Scopus数据库比较研究──以图书情报学科为例 被引量:4
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作者 徐速 《情报科学》 CSSCI 北大核心 2016年第3期98-101,共4页
作为基于引文分析的期刊评价工具,Google Scholar Metrics打破了Web of Science和Scopus在科学评价领域的垄断地位。本文以图书情报学科为例,通过对三个数据库资源覆盖程度的比较和期刊排名的相关性分析,了解Google Scholar Metrics和... 作为基于引文分析的期刊评价工具,Google Scholar Metrics打破了Web of Science和Scopus在科学评价领域的垄断地位。本文以图书情报学科为例,通过对三个数据库资源覆盖程度的比较和期刊排名的相关性分析,了解Google Scholar Metrics和传统引文数据库的差异和联系。研究表明,Google Scholar Metrics不仅覆盖了广泛的资源,而且在期刊排名方面,同Web of Science和Scopus具有很高的相关性,能够提供可靠有效的评价结果。 展开更多
关键词 图书情报学科 Google SCHOLAR metrics Web of Science SCOPUS 期刊评价
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