Evaluation of Functional Data Models for Database Design and Use

The problems of design, operation, and maintenance of databases using the three most popular database management systems (Hierarchical, CQDASYL/DBTG, and Relational) are well known. Users wishing to use these systems have to make conscious and often complex mappings between the real-world structures and the data structuring options (data models) provided by these systems. In addition, much of the semantics associated with the data either does not get expressed at all or gets embedded procedurally in application programs in an ad-hoc way. In recent years, a large number of data models (called semantic data models) have been proposed with the aim of simplifying database design and use. However, the lack of usable implementations of these proposals has so far inhibited the widespread use of these concepts. The present work reports on an effort to evaluate and extend one such semantic model by means of an implementation. It is based on the functional data model proposed earlier by Shipman[SHIP81). We call this 'Extended Functional Data Model' (EFDM). EFDM, like Shipman's proposals, is a marriage of three of the advanced modelling concepts found in both database and artificial intelligence research: the concept of entity to represent an object in the real world, the concept of type hierarchy among entity types, and the concept of derived data for modelling procedural knowledge. The functional notation of the model lends itself to high level data manipulation languages. The data selection in these languages is expressed simply as function application. Further, the functional approach makes it possible to incorporate general purpose computation facilities in the data languages without having to embed them in procedural languages. In addition to providing the usual database facilities, the implementation also provides a mechanism to specify multiple user views of the database

Studies related to the process of program development

The submitted work consists of a collection of publications arising from research carried out at Rhodes University (1970-1980) and at Heriot-Watt University (1980-1992). The theme of this research is the process of program development, i.e. the process of creating a computer program to solve some particular problem. The papers presented cover a number of different topics which relate to this process, viz. (a) Programming methodology programming. (b) Properties of programming languages. aspects of structured. (c) Formal specification of programming languages. (d) Compiler techniques. (e) Declarative programming languages. (f) Program development aids. (g) Automatic program generation. (h) Databases. (i) Algorithms and applications

Performance optimisation of biological pathway data storage, retrieval, analysis and its interactive visualisation

The aim of this research was to optimise the performance of the storage, retrieval, analysis and interactive visualisation of biomolecular pathways data. This was achieved by the adoption of new technologies and a variety of highly optimised data structures, algorithms and strategies across the different layers of the software. The first challenge to overcome was the creation of a long-lasting, large-scale web application to enable pathways navigation; the Pathway Browser. This tool had to aggregate different modules to allow users to browse pathway content and use their own data to perform pathway analysis. Another challenge was the development of a high-performance pathway analysis tool to enable the analysis of genome-wide datasets within seconds. Once developed, it was also integrated into the Pathway Browser allowing interactive exploration and analysis of high throughput data. The Pathways Overview layout and widget were created to enable the representation of the complex parent-child relationships present in the pathways hierarchical organisation. This module provides a means to overlay analysis results in such a way that the user can easily distinguish the most significant areas of biology represented in their data. Although an existing force-directed layout algorithm was initially utilised for the graphical representation, it did not achieve the expected results and a custom radial layout algorithm was developed instead. A new version of the pathway Diagram Viewer was engineered to achieve loading and rendering of 97% of the target diagrams in less than 1 second. Combining the multi-layer HTML5 Canvas strategy with a space partitioning data structure minimised CPU workload, enabling the introduction of new features that further enhance user experience. On the server side, the work focused on the adoption of a graph database (Neo4j) and the creation of the new Content Service (REST API) that provides access to these data. The Neo4j graph database and its query language, Cypher, enabled efficient access to the complex pathway data model, facilitating easy traversal and knowledge discovery. The adoption of this technology greatly improved query efficiency, reducing the average query time by 93%

Data bases and data base systems related to NASA's aerospace program. A bibliography with indexes

This bibliography lists 1778 reports, articles, and other documents introduced into the NASA scientific and technical information system, 1975 through 1980