DOI: 10.3897/jucs.2020.007

Authors: Anastasija Nikiforova, Janis Bicevskis, Zane Bicevska, Ivo Oditis

Abstract: The paper proposes a new data object-driven approach to data quality evaluation. It consists of three main components: (1) a data object, (2) data quality requirements, and (3) data quality evaluation process. As data quality is of relative nature, the data object and quality requirements are (a) use-case dependent and (b) defined by the user in accordance with his needs. All three components of the presented data quality model are described using graphical Domain Specific Languages (DSLs). In accordance with Model-Driven Architecture (MDA), the data quality model is built in two steps: (1) creating a platform-independent model (PIM), and (2) converting the created PIM into a platform-specific model (PSM). The PIM comprises informal specifications of data quality. The PSM describes the implementation of a data quality model, thus making it executable, enabling data object scanning and detecting data quality defects and anomalies. The proposed approach was applied to open data sets, analysing their quality. At least 3 advantages were highlighted: (1) a graphical data quality model allows the definition of data quality by non-IT and non-data quality experts as the presented diagrams are easy to read, create and modify, (2) the data quality model allows an analysis of "third-party" data without deeper knowledge on how the data were accrued and processed, (3) the quality of the data can be described at least at two levels of abstraction - informally using natural language or formally by including executable artefacts such as SQL statements.

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DOI: 10.3217/jucs-021-11-1439

Authors: Mehedi Masud, M. Hossain, Atif Alamri, Ahmad Almogren, Mohammed Zakariah

Abstract: Data interoperability and synchronization among heterogeneous data providers in collaborative e-health systems are challenging research issues. Efficient data management techniques promote an efficient way of sharing data. This paper describes existing approaches to data interoperability (platform independency) for exchanging and synchronizing data between heterogeneous data sources or various platforms. We also illustrate an update query execution protocol, which can reduce query execution cost and query response time. We further perform different experiments to validate the effectiveness of the proposed approaches.

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DOI: 10.3217/jucs-014-22-3658

Authors: Ismael Caballero, Angélica Caro, Coral Calero, Mario Piattini

Abstract: In order to enhance their global business performance, organizations must be careful with the quality of their information since it is one of their main assets. Analogies to quality management of classical products demonstrate that Information Quality is also preferably attainable through management by integrating some corresponding Information Quality management activities into the organizational processes. To achieve this goal we have developed an Information Quality Management Framework (IQMF). It is articulated on the concept of Information Management Process (IMP), based on the idea of Software Process. An IMP is a combination of two sub-processes: the first, a production process, aimed to manufacture information from raw data, and the second to adequately manage the required Information Quality level of the first. IQMF consists of two main components: an Information Quality Management Maturity Model (IQM3), and a Methodology for the Assessment and Improvement of Information Quality Management (MAIMIQ), which uses IQM3 as a reference model for the assessment and for the improvement goal of an IMP. Therefore, as a result of an assessment with MAIMIQ, an IMP can be said to have raised one of the maturity levels described in IQM3, and as improvement goal, it would be desirable to achieve a higher maturity level. Since an Information System can be seen as a set of several IMPs sharing several resources, it is possible to improve the Information Quality level of the entire Information System by improving the most critical IMPs. This paper is focused only on describing the foundations and structure of IQM3, which is based on staged CMMI.

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DOI: 10.3217/jucs-006-01-0060

Authors: Dana Cristofor, Laurentiu Cristofor, Dan Simovici

Abstract: We investigate the application of Galois connections to the identification of frequent item sets, a central problem in data mining. Starting from the notion of closure generated by a Galois connection, we define the notion of extended closure, and we use these notions to improve the classical Apriori algorithm. Our experimental study shows that in certain situations, the algorithms that we describe outperform the Apriori algorithm. Also, these algorithms scale up linearly. 1 C.S.Calude and G.Stefanescu (eds.). Automata, Logic, and Computability. Special issue dedicated to Professor Sergiu Rudeanu Festschrift.

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DOI: 10.3217/jucs-003-06-0730

Authors: Ahmad Baraani-Dastjerdi, Josef Pieprzyk, Reihaneh Safavi-Naini, Janusz Getta

Abstract: This is a discussion paper which presents a cryptographic solution for discretionary access control in object-oriented databases. Our approach is based on the use of pseudo-random functions and sibling intractable function families (SIFF). Each entity (object or class) in the object-oriented database model is associated with access keys that ensure secure access to that entity and all related entities. The main advantage of our approach is its ability to verify an access request during query processing. Pseudo-random functions and SIFF are applied in such a way that cryptographic keys can be generated from keys of related objects or users. The security of the system depends on the difficulty of predicting the output of pseudo-random functions and on finding extra collision for the sibling intractable function family. The authorization system supports ownership and granting/revoking of privileges.

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