Results 31 to 40 of about 342,288 (312)
Measuring accessibility: A Big Data perspective on Uber service waiting times [PDF]
RAE: Revista de Administração de Empresas, 2019 This study aims to relate information about the waiting times of ride-sourcing services, with specific reference to Uber, using socioeconomic variables from São Paulo, Brazil.
André Insardi, Rodolfo Oliveira Lorenzo
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Recommendations for Evolving Relational Databases [PDF]
, 2020 Relational databases play a central role in many information systems. Their schemas contain structural and behavioral entity descriptions. Databases must continuously be adapted to new requirements of a world in constant change while: (1) relational database management systems (RDBMS) do not allow inconsistencies in the schema; (2) stored procedure ...
Delplanque, Julien +3 more
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Fuzzy relations and fuzzy relational databases
Computers & Mathematics with Applications, 1991 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Austin Melton, Sujeet Shenoi
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Tạp chí Khoa họcThe paper presents a watermarked scheme based on the most significant bit for public copyright protection for relational databases. A Watermark scheme could openly prove data copyright as often as desired.
Luu Thi Bich Huong
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The Scientific World Journal, 2013 We put forward a fragile zero watermarking scheme to detect and characterize malicious modifications made to a database relation. Most of the existing watermarking schemes for relational databases introduce intentional errors or permanent distortions as ...
Aihab Khan, Syed Afaq Husain
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AKAP12 Expression in HER2-positive Breast Cancer and Its Clinical Significance
Zhongliu Fangzhi Yanjiu, 2020 Objective To investigate the expression of AKAP12 in HER2-positive breast cancer and its relation with clinicopathological factors and clinical significance.
CHENG Qian +5 more
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The Fast Parsing and Generating Method of Airborne Navigation Database Based on Relation Model
Hangkong gongcheng jinzhan, 2019 Navigation database can be used for navigation calculation and automatic tuning management of navigation platform, etc. It is the necessary data sources for flight management system.
Li Li
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Journal of Medical Internet Research, 2023 BackgroundBiomedical relation extraction (RE) is of great importance for researchers to conduct systematic biomedical studies. It not only helps knowledge mining, such as knowledge graphs and novel knowledge discovery, but also ...
Zeyu Zhang +11 more
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Database relations with null values [PDF]
Journal of Computer and System Sciences, 1982 A new formalism for null values is developed, based on the semantics that a null value conveys no information; that it is less informative then either an ''exists but unknown'' or a ''no value'' null. What results is a theory of ''heterogeneous relations'': relations with tuples over different schemes.
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Adequacy of Decompositions of Relational Databases
Journal of Computer and System Sciences, 1980 AbstractWe consider conditions that have appeared in the literature with the purpose of defining a “good” decomposition of a relation scheme. We show that these notions are equivalent in the case that all constraints in the database are functional dependencies. This result solves an open problem of Rissanen.
Fereidoon Sadri +3 more
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