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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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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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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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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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COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE) 被引量:1
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作者 段晓曼 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期78-102,共25页
In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strateg... In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry. 展开更多
关键词 Kahler metrics complete Riemannian metrics open complex manifolds holomorphic bisectional curvature C*bundle almost homogeneous manifolds
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Integrating vegetation phenological characteristics and polarization features with object-oriented techniques for grassland type identification 被引量:1
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作者 Bin Sun Pengyao Qin +5 位作者 Changlong Li Zhihai Gao Alan Grainger Xiaosong Li Yan Wang Wei Yue 《Geo-Spatial Information Science》 CSCD 2024年第3期794-810,共17页
Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depic... Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depiction.This limitation significantly hampers the development of effective evaluation and fine supervision for the rational utilization of grassland resources.To address this issue,this study concentrates on the representative grassland of Zhenglan Banner in Inner Mongolia as the study area.It integrates the strengths of Sentinel-1 and Sentinel-2 active-passive synergistic observations and introduces innovative object-oriented techniques for grassland type classification,thereby enhancing the accuracy and refinement of grassland classification.The results demonstrate the following:(1)To meet the supervision requirements of grassland resources,we propose a grassland type classification system based on remote sensing and the vegetation-habitat classification method,specifically applicable to natural grasslands in northern China.(2)By utilizing the high-spatial-resolution Normalized Difference Vegetation Index(NDVI)synthesized through the Spatial and Temporal Non-Local Filter-based Fusion Model(STNLFFM),we are able to capture the NDVI time profiles of grassland types,accurately extract vegetation phenological information within the year,and further enhance the temporal resolution.(3)The integration of multi-seasonal spectral,polarization,and phenological characteristics significantly improves the classification accuracy of grassland types.The overall accuracy reaches 82.61%,with a kappa coefficient of 0.79.Compared to using only multi-seasonal spectral features,the accuracy and kappa coefficient have improved by 15.94%and 0.19,respectively.Notably,the accuracy improvement of the gently sloping steppe is the highest,exceeding 38%.(4)Sandy grassland is the most widespread in the study area,and the growth season of grassland vegetation mainly occurs from May to September.The sandy meadow exhibits a longer growing season compared with typical grassland and meadow,and the distinct differences in phenological characteristics contribute to the accurate identification of various grassland types. 展开更多
关键词 Grassland types vegetation phenological characteristics polarization feature integrated active and passive remote sensing object-oriented classification
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Navigation Finsler metrics on a gradient Ricci soliton
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作者 LI Ying MO Xiao-huan WANG Xiao-yang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期266-275,共10页
In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to b... In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral inequality.Then we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein type.As its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton. 展开更多
关键词 gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton
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Research on Building Extraction Based on Object-oriented CART Classification Algorithm and GF-2 Satellite Images
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作者 HUANG Wei CUI Zhimei +1 位作者 HUANG Zhidu WU Rongrong 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第4期5-18,共14页
As one of the main geographical elements in urban areas,buildings are closely related to the development of the city.Therefore,how to quickly and accurately extract building information from remote sensing images is o... As one of the main geographical elements in urban areas,buildings are closely related to the development of the city.Therefore,how to quickly and accurately extract building information from remote sensing images is of great significance for urban map updating,urban planning and construction,etc.Extracting building information around power facilities,especially obtaining this information from high-resolution images,has become one of the current hot topics in remote sensing technology research.This study made full use of the characteristics of GF-2 satellite remote sensing images,adopted an object-oriented classification method,combined with multi-scale segmentation technology and CART classification algorithm,and successfully extracted the buildings in the study area.The research results showed that the overall classification accuracy reached 89.5%and the Kappa coefficient was 0.86.Using the object-oriented CART classification algorithm for building extraction could be closer to actual ground objects and had higher accuracy.The extraction of buildings in the city contributed to urban development planning and provided decision support for management. 展开更多
关键词 object-oriented high-resolution image image segmentation CART decision tree building extraction
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Green analytical chemistry metrics for evaluating the greenness of analytical procedures
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作者 Lei Yin Luyao Yu +7 位作者 Yingxia Guo Chuya Wang Yuncheng Ge Xinyue Zheng Ning Zhang jiansong You Yong Zhang Meiyun Shi 《Journal of Pharmaceutical Analysis》 CSCD 2024年第11期1542-1555,共14页
Green analytical chemistry(GAC)focuses on mitigating the adverse effects of analytical activities on human safety,human health,and environment.In addition to the 12 principles of GAC,proper GAC tools should be develop... Green analytical chemistry(GAC)focuses on mitigating the adverse effects of analytical activities on human safety,human health,and environment.In addition to the 12 principles of GAC,proper GAC tools should be developed and employed to assess the greenness of different analytical assays.The 15 widely used GAC metrics,i.e.,national environmental methods index(NEMI),advanced NEMI,assessment of green profile(AGP),chloroform-oriented toxicity estimation scale(ChlorTox Scale),Analytical Eco-Scale,Green Certificate Modified Eco-Scale,analytical method greenness score(AMGS),green analytical procedure index(GAPI),ComplexGAPI,red-green-blue(RGB)additive color model,RGB 12 algorithm,analytical greenness calculator(AGREE),AGREE preparation(AGREEprep),HEXAGON,and blue applicability grade index(BAGI),are selected as the typical tools.This article comprehensively presents and elucidates the principles,characteristics,merits,and demerits of 15 widely used GAC tools.This review is helpful for researchers to use the current GAC metrics to assess the environmental sustainability of analytical assays. 展开更多
关键词 Greenness metric Green analytical chemistry Analytical methods Environmental sustainability
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The Correct Reissner-Nordstrøm, Kerr and Kerr-Newman Metrics
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作者 Carlo Maria Pace 《Journal of Modern Physics》 2024年第10期1502-1522,共21页
In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. I... In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. In this article, starting from this correct Schwarzschild metric, I also propose corrections to the other traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics on the basis of the fact that these metrics should be equal to the correct Schwarzschild metric in the borderline case in which they reduce to the case described by this metric. In this way, we see that, like the correct Schwarzschild metric, also the correct Reissner-Nordstrøm, Kerr and Kerr-Newman metrics do not present any event horizon (and therefore do not present any black hole) unlike the traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics. 展开更多
关键词 General Theory of Relativity SCHWARZSCHILD Reissner-Nordstrøm KERR Kerr-Newman metric Event Horizon Black Hole
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An Approach to Detect Structural Development Defects in Object-Oriented Programs
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作者 Maxime Seraphin Gnagne Mouhamadou Dosso +1 位作者 Mamadou Diarra Souleymane Oumtanaga 《Open Journal of Applied Sciences》 2024年第2期494-510,共17页
Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detecti... Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detection approaches, ranging from traditional heuristic algorithms to machine learning methods, are used to identify these defects. Ensemble learning methods have strengthened the detection of these defects. However, existing approaches do not simultaneously exploit the capabilities of extracting relevant features from pre-trained models and the performance of neural networks for the classification task. Therefore, our goal has been to design a model that combines a pre-trained model to extract relevant features from code excerpts through transfer learning and a bagging method with a base estimator, a dense neural network, for defect classification. To achieve this, we composed multiple samples of the same size with replacements from the imbalanced dataset MLCQ1. For all the samples, we used the CodeT5-small variant to extract features and trained a bagging method with the neural network Roberta Classification Head to classify defects based on these features. We then compared this model to RandomForest, one of the ensemble methods that yields good results. Our experiments showed that the number of base estimators to use for bagging depends on the defect to be detected. Next, we observed that it was not necessary to use a data balancing technique with our model when the imbalance rate was 23%. Finally, for blob detection, RandomForest had a median MCC value of 0.36 compared to 0.12 for our method. However, our method was predominant in Long Method detection with a median MCC value of 0.53 compared to 0.42 for RandomForest. These results suggest that the performance of ensemble methods in detecting structural development defects is dependent on specific defects. 展开更多
关键词 object-oriented Programming Structural Development Defect Detection Software Maintenance Pre-Trained Models Features Extraction BAGGING Neural Network
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Quantum Metric, Topology and Second Harmonic Generation
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作者 En Wang Yaxian Wang Sheng Meng 《Chinese Physics Letters》 2025年第4期99-113,共15页
The quantum metric manifested as the Riemannian metric in the parameter space of Bloch bands,characterizes the topology and geometry of quantum states.The second harmonic generation(SHG),as one of the fundamental nonl... The quantum metric manifested as the Riemannian metric in the parameter space of Bloch bands,characterizes the topology and geometry of quantum states.The second harmonic generation(SHG),as one of the fundamental nonlinear optical responses that links geometry of optical transitions to physical observables,despite being widely studied in various materials,its relation to quantum metric,especially in the dynamical regime,stays obscure. 展开更多
关键词 second harmonic generation shg quantum metric quantum metricespecially geometry optical transitions nonlinear optical responses bloch bandscharacterizes riemannian metric TOPOLOGY
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GÂTEAUX DIRECTIONAL DIFFERENTIABILITY OF THE GENERALIZED METRIC PROJECTION IN BANACH SPACES
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作者 Jinlu LI 《Acta Mathematica Scientia》 2025年第4期1597-1618,共22页
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap... Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC. 展开更多
关键词 uniformly convex and uniformly smooth Banach space the generalized metric projection directional differentiability of the generalized metric projection directional derivative of the generalized metric projection
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科学论文政策影响力计量的数据库选择——基于Altmetric与Overton的比较
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作者 方志超 郑尔特 《图书情报知识》 北大核心 2025年第1期18-28,共11页
[目的/意义]各类政策引文数据库因索引范围的差异,可能导致围绕科学论文的政策计量分析结果的不同。需要通过比较研究来理解不同数据库所能提供的数据基础的差异,以更好地支持科研成果的政策影响力计量与评价。[研究设计/方法]比较了同... [目的/意义]各类政策引文数据库因索引范围的差异,可能导致围绕科学论文的政策计量分析结果的不同。需要通过比较研究来理解不同数据库所能提供的数据基础的差异,以更好地支持科研成果的政策影响力计量与评价。[研究设计/方法]比较了同时期内Altmetric和Overton两大主流政策引文数据库收录的政策文件范围的异同。并面向约1,700万篇科学论文,比较了Altmetric和Overton数据库提供的政策引文数据在覆盖范围、数据体量、学科分布等方面的差异。[结论/发现]相比于Altmetric,Overton提供了范围更广、数量更多的政策文件和政策引文,表现出显著的数据优势。但Altmetric与Overton收录的政策文件仅有小部分重合,二者代表了不同决策主体不同的政策观点和科学证据使用行为,难以相互替代,可以互为补充。[创新/价值]在科研成果的政策影响力定量评价中,应注意和警示政策引文数据库选择对结果可能造成的影响,制定合理的数据获取策略,以实现更负责任的评价。 展开更多
关键词 政策计量 科研评价 社会影响力 科学计量学 替代计量学
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