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To provide a selective bibliography for researchers and practitioners interested in database modeling of engineering information with sources which can help them develop engineering information systems.

Identifies the requirements for engineering information modeling and then investigates how current database models satisfy these requirements at two levels: conceptual data models and logical database models.

Presents the relationships among the conceptual data models and the logical database models for engineering information modeling viewed from database conceptual design.

Currently few papers provide comprehensive discussions about how current engineering information modeling can be supported by database technologies. This paper fills this gap. The contribution of the paper is to identify the direction of database study viewed from engineering applications and provide a guidance of information modeling for engineering design, manufacturing, and production management.

Getting the right information at the right time is one of the success factors of product development. However, there exist a great variety of data formats which make the bi‐directional data interchange among various development groups inefficient and costly. Due to the lack of adequate product and engineering data, design practitioners may find it difficult to transform the customer’s requirements to a value‐added product. This paper attempts to propose a hybrid database approach (HDA) to support effective data exchange among a case based reasoning knowledge repository and a corporate relational database model, presenting an integrated view of a company’s knowledge sources so as to enable better decision‐making by providing immediate access to key business information. To introduce machine learning capability to the whole system, case based reasoning (CBR) is embraced to capture past experience and knowledge for case matching in terms of product development issues. The significance of this research is the provision of a cross‐platform data exchange system, which is able to facilitate the creation of a conducive product development environment.

A database for finite element models and related data is developed and incorporated into a prototype system for integration of non‐linear finite element codes with a product design system. In the prototype system, the database is used as a link for integrating commercial, public domain as well as in‐house codes. In the present system, the public domain finite element codes NIKE2D, NIKE3D, DYNA2D, DYNA3D and TOPAZ2D are integrated with the CIM–system I–DEAS. The prototype system is primarily intended as a platform in research projects for development of integrated environments tuned for simulations of specific manufacturing processes such as quenching, welding, hot rolling, metal powder compaction and hot isostatic pressing.

This research conducted two experiments to understand the performance (correctness and efficiency) of novice database designers, and perceptions of ease of use and preferences of two approaches for modeling relational databases: the semantic‐oriented approach (top‐down, e.g. using the entity‐relationship model) and the logical‐oriented approach (bottom‐up, view decomposition, focusing only on the logical model). The findings indicated that in experiment 1, semantic‐oriented treatments performed better in a complex, written‐text case; logical‐oriented treatments were better in a simple, tabular‐form case. The same situation happened in experiment 2 though the differences were not statistically significant.

The paper aims to focus on so‐called NoSQL databases in the context of cloud computing.

Architectures and basic features of these databases are studied, particularly their horizontal scalability and concurrency model, that is mostly weaker than ACID transactions in relational SQL‐like database systems.

Some characteristics like a data model and querying capabilities of NoSQL databases are discussed in more detail.

The paper shows vary different data models and query possibilities in a common terminology enabling comparison and categorization of NoSQL databases.

It is generally recognised that numeric databases (NDBs) have become essential in information retrieval (IR). NDBs differ from traditional bibliographic databases (BDBs) with respect to their content, structural complexity, data manipulation capabilities, and the complexity of the user interfaces and user charging schemes. Recent trends in user interfaces and user charging for all online IR are towards charging for the information actually retrieved from the database rather than for the connect time. However, the viability of such charging schemes depends on the user's ability to estimate the charges in advance, during the query negotiation phase. This paper presents a systematic and general method for estimating user charges for retrieved information in advance, in the context of NDBs based on the relational data model (RDM). The method accepts relational algebra (RA) queries of any complexity, estimates the sizes of their results, and charges for them on the basis of the descriptions of the original database files. The method is a novel one and is directly applicable to any RDM‐based NDB. Tools based on the method are required in the query interfaces to NDBs in order to make query formulation and reformulation meaningful.

A relational database management system is presented that is tailored for engineering applications. A wide variety of engineering data types is supported and the data definition language (DDL) and data manipulation language (DML) are extended to handle engineering operations. The system can be used either in the stand‐alone mode or through a FORTRAN or PASCAL application program. The query language is of the relational calculus type and allows the user to store, retrieve, update and delete tuples from relations. The relational operations including union, intersect and differ facilitate creation of temporary relations that can be used for manipulating information in a powerful manner. Sample applications are shown to illustrate the creation of data through a FORTRAN program and data manipulation using the TEQUEL DML.

Changes in market and production profiles require a more flexible concept in manufacturing. Computer integrated manufacturing (CIM) describes an integrative concept for joining business and manufacturing islands. In this context, database technology is the key technology for implementing the CIM philosophy. However, CIM applications are more complex and thus more demanding than traditional database applications such as business and administrative applications. Systematically analyses the database requirements for CIM applications including business and manufacturing tasks. Special emphasis is given on integration requirements due to the distributed, partly isolated nature of CIM applications developed over the years. An illustrative sampling of current efforts in the database community to meet the challenge of non‐standard applications such as CIM is presented.

HIFI (ESPRIT Project 6532) creates a set of tools to allow a reader to access a large body of heterogeneous information, managed by external databases created beforehand, through a hypertext interface. Information currently found in information systems is based on different media and is usually managed by different tools, like relational databases and a variety of multimedia database systems. Sometimes the need arises to ‘browse’ through the information using an interactive and intuitive interface. Hypertext is probably the best current means for interactive (and possibly intuitive) navigation through a heterogeneous body of information. Available hypertext tools, however, are usually seen as being for managing their own information rather than being an interface for accessing external databases. The HIFI approach is based on a model‐based description of the hypertext application, as it appears to the reader. A declarative and/or operational mapping translates hypertext operations (search, queries and navigation) into operations on the underlying information base and also ‘materialises’ hypertext objects, using objects of the underlying databases. The system also implements methodologies to support the hypertext interface development process. Real‐life applications will be developed to show the validity of the approach, with the cooperation of important end‐users who will cooperate with the project directly, either as partners or sponsors.

Relational Database Management Systems (RDBMS) have a proven track record for storing and managing many different forms of digital content, and new strategies have been defined to provide RDBMS‐based solutions for XML. Some relational databases now offer special mechanisms to accommodate XML while several technologies have emerged to facilitate the use of XML representations of data housed within an RDBMS. In addition to presenting challenges and opportunities to RDBMS developers, XML and XML‐enabled technologies may find new application for libraries by combining RDBMS concepts with Web‐based services.