On the emergent Semantic Web and overlooked issues

The emergent Semantic Web, despite being in its infancy, has already received a lotof attention from academia and industry. This resulted in an abundance of prototype systems and discussion most of which are centred around the underlying infrastructure. However, when we critically review the work done to date we realise that there is little discussion with respect to the vision of the Semantic Web. In particular, there is an observed dearth of discussion on how to deliver knowledge sharing in an environment such as the Semantic Web in effective and efficient manners. There are a lot of overlooked issues, associated with agents and trust to hidden assumptions made with respect to knowledge representation and robust reasoning in a distributed environment. These issues could potentially hinder further development if not considered at the early stages of designing Semantic Web systems. In this perspectives paper, we aim to help engineers and practitioners of the Semantic Web by raising awareness of these issues

Designing and Implementing a Distributed Database for a Small Multi-Outlet Business

Data is a fundamental and necessary element for businesses. During their operations they generate a certain amount of data that they need to capture, store, and later on retrieve when required. Databases provide the means to store and effectively retrieve data. Such a database can help a business improve its services, be more competitive, and ultimately increase its profits. In this paper, the system requirements of a distributed database are researched for a movie rental and sale store that has at least two outlets in different locations besides the main one. This project investigates the different stages of such a database, namely, the planning, analysis, decision, implementation and testing

Cost and Performance Analysis of Integrity Validation Techniques for a Distributed Database

A principal problem with the use of integrity constraints for monitoring the integrity of a dynamically changing database is their cost of evaluation. This cost which is associated with the performance of the checking mechanisms is the main quantitative measure which has to be supervised carefully. We have developed an integrity constraint subsystem for a relational distributed database (SICSDD) which consists of several techniques that are necessary for efficient constraint checking, particularly in a distributed environment where data distribution is transparent to the application domain. In this paper, we will show how these techniques have effectively reduced the cost of constraint checking in such a distributed environment

On the Quality of Relational Database Schemas in Open-source Software

International audienceThe relational schemas of 512 open-source projects storing their data in MySQL or PostgreSQL databases are investigated by querying the standard information schema, looking for overall design issues. The set of SQL queries used in our research is released as the Salix free software. As it is fully relational and relies on standards, it may be installed in any compliant database to help improve schemas. Our research shows that the overall quality of the surveyed schemas is poor: a majority of projects have at least one table without any primary key or unique constraint to identify a tuple; data security features such as referential integrity or transactional back-ends are hardly used; projects that advertise supporting both databases often have missing tables or attributes. PostgreSQL projects appear to be of higher quality than MySQL projects, and have been updated more recently, suggesting a more active maintenance. This is even better for projects with PostgreSQL-only support. However, the quality difference between both databases management systems is mostly due to MySQL-specific issues. An overall predictor of bad database quality is that a project chooses MySQL or PHP, while good design is found with PostgreSQL and Java. The few declared constraints allow to detect latent bugs, that are worth fixing: more declarations would certainly help unveil more bugs. Our survey also suggests that some features of MySQL and PostgreSQL are particularly error-prone. This first survey on the quality of relational schemas in open-source software provides a unique insight in the data engineering practice of these projects

Database Design and Implementation

The book of Database Design and Implementation is a comprehensive guide that provides a thorough introduction to the principles, concepts, and best practices of database design and implementation. It covers the essential topics required to design, develop, and manage a database system, including data modeling, database normalization, SQL programming, and database administration. The book is designed for students, database administrators, software developers, and anyone interested in learning how to design and implement a database system. It provides a step-by-step approach to database design and implementation, with clear explanations and practical examples. It also includes exercises and quizzes at the end of each chapter to help reinforce the concepts covered. The book begins by introducing the fundamental concepts of database systems and data modeling. It then discusses the process of database design and normalization, which is essential for creating a well-structured and efficient database system. The book also covers SQL programming, which is used for querying, updating, and managing data in a database. Additionally, it includes a comprehensive discussion on database administration, including security, backup and recovery, and performance tuning.https://orc.library.atu.edu/atu_oer/1002/thumbnail.jp

Database machines in support of very large databases

Software database management systems were developed in response to the needs of early data processing applications. Database machine research developed as a result of certain performance deficiencies of these software systems. This thesis discusses the history of database machines designed to improve the performance of database processing and focuses primarily on the Teradata DBC/1012, the only successfully marketed database machine that supports very large databases today. Also reviewed is the response of IBM to the performance needs of its database customers; this response has been in terms of improvements in both software and hardware support for database processing. In conclusion, an analysis is made of the future of database machines, in particular the DBC/1012, in light of recent IBM enhancements and its immense customer base

A semantically-enriched goal-oriented requirements engineering framework for systems of systems using the i* framework applied to cancer care

In recent years, monolithic systems are being composed into bigger systems as Systems of Systems (SoSs). This evolution of SoS raises several software engineering key challenges, such as the management of emerging inconsistent goals and requirements, which may occur among the various Constituent Systems (CSs) themselves, as well as between the entire SoS and the participating CSs. Another significant challenge is that Systems of Systems Engineering (SoSE) involves more stakeholders than traditional systems engineering, i.e. stakeholders at the SoS-level and the CS-level, where each CS has its own needs and objectives which establish a complex stakeholder environment. To respond to these challenges, this research is aimed at investigating the implications of applying a goal-oriented requirements engineering approach in identifying, modelling and managing emerging goals and their conflicts in SoS context. The key artefact of this research is the development of a Semantically-Enriched Goal-Oriented Requirements Engineering Framework for Systems of Systems using the i* framework, namely the OntoSoS.GORE framework.The OntoSoS.GORE is a three-layered framework designed, developed, demonstrated and then evaluated through following multiple iterations of the Design Science Research Methodology (DSRM) phases, to accomplish the following main objectives: (1) identifying and modelling the SoS global goals and the CSs local goals at different levels of an SoS using the i* framework, in which a new process to extract i* modelling elements from existing user documentation is proposed; (2) maintaining the consistency and integrity of SoS goals at multiple levels through developing a semantic Goals Referential Integrity (sGRI) model in SoS context which consists of an SoSGRI model and an ontology-based model; and (3) managing any conflicts that may occur amongst goals at both the SoS-level and the CS-level, by developing and applying a new goal conflict management approach in SoS context, which consists of two main processes: goal conflict detection and goal conflict resolution.The research framework has been instantiated and validated by applying a real Cancer Care case study at King Hussein Cancer Center (KHCC), Amman, Jordan. Results revealed the effectiveness of applying the framework compared to the current approach applied at KHCC, in terms of addressing higher consistency, completeness and correctness with regard to goal management and conflict management in SoS context. Moreover, the framework provides automation of the processes of following the satisfaction of goals and goals’ conflict management at multiple SoS levels, instead of the manual approach applied currently at KHCC. This automation is accomplished through developing a strategic goal-oriented management tool that is anticipated to be delivered and utilised at KHCC, as well as applying it to other SoS organisations as a proposed solution for goal and conflict management. Another contribution to the Cancer Care and SoS domains is developing a reference i* goal-oriented model for access to Cancer Care which provides a wider system engineering perspective and offers an accessible level of abstraction about Cancer Care goals and their dependencies for stakeholders and domain experts. The reference model provides standardisation of common generic concepts about the domain, in which other Cancer Care organisations can considerably reuse to facilitate the process of capturing and specifying goals and requirements for their practice and validating choices among alternative designs