Cornelia Boldyreff

Successful Reuse of Software Components: A Report from the Open Source Perspective

A promising way of software reuse is Component-Based Software Development (CBSD). There is an increasing number of OSS products available that can be freely used in product development. However, OSS communities themselves have not yet taken full advantage of the “reuse mechanism”. Many OSS projects duplicate effort and code, even when sharing the same application domain and topic. One successful counter-example is the FFMpeg multimedia project, since several of its components are widely and consistently reused into other OSS projects. This paper documents the history of the libavcodec library of components from the FFMpeg project, which at present is reused in more than 140 OSS projects. Most of the recipients use it as a black-box component, although a number of OSS projects keep a copy of it in their repositories, and modify it as such. In both cases, we argue that libavcodec is a successful example of reusable OSS library of components.

Architectural studies of games engines — The quake series

The presented approach constitutes a useful resource for games developers who wish to contribute to the further evolution of these games engines; and it provides insights into how the Quake engine architecture has evolved in practice since it was released as an open source project.

Cost-effective virtual world development for serious games

Developing a virtual world environment from scratch normally involves a large number of model creations, animations and event simulations. Such undertakings generally require a large amount of man-hours and expensive software. This paper introduces an open-source approach that will enable developers to easily and quickly create scenario-driven collaborative environments for serious games. A case study based on the development of a virtual crisis room in the Pandora project1 is provided to demonstrate the effectiveness of the approach.

Patterns of creation and usage of Wikipedia content

Wikipedia is the largest online service storing user-generated content. Its pages are open to anyone for addition, deletion and modifications, and the effort of contributors is recorded and can be tracked in time. Although potentially the Wikipedia web content could exhibit unbounded growth, it is still not clear whether the effort of developers and the output generated are actually following patterns of continuous growth. It is also not clear how the users access such content, and if recurring patterns of usage are detectable showing how the Wikipedia content typically is viewed by interested readers. Using the category of Wikipedia as macro-agglomerates, this study reveals that Wikipedia categories face a decreasing growth trend over time, after an initial, exponential phase of development. On the other hand the study demonstrates that the number of views to the pages within the categories follow a linear, unbounded growth. The link between software usefulness and the need for software maintenance over time has been established by Lehman and other; the link between Wikipedia usage and changes to the content, unlike software, appear to follow a two-phase evolution of production followed by consumption.

A High Level Service-Based Approach to Software Component Integration

This paper motivates and sets out a framework for a high-level approach to software component integration. The framework builds on the concept of SaaS (Software as a Service) and uses a service ontology for the annotation of software components with formal specifications. The ontology is used to instruct interoperability between software components through a unified API interface. The impetus for this approach is to provision for smooth integration, management and scalability in a collaborative and distributed development environment.

Payments as We Know Them Are Changing––ebarts the Social eCurrency: Tomorrow’s Cash

ebarts is a mutual exchange digital currency, which enables people to buy and sell without money. It has been created with a strong social purpose to unlock idle skills and resources within communities, and to encourage the growth of a social economy. ebarts are used in a secure, mobile-based marketplace for trading goods and services, and generate value from exchange. In this paper, we discuss the user-centred design process we have employed to build an ebarts marketplace platform, focusing on people’s expectations for creating and using ebarts. Our design reflects our findings that people are geared by a want to reduce waste and generate value from possessions, skills and time that would otherwise be wasted. Correlating people’s responses from focus groups indicates that social entrepreneurship can be nurtured by such marketplaces, and that there is need for a space to be created in society for individuals to engage their entrepreneurial creativity for their own benefit as well as directly affecting their communities. Finally, based on our development of ebarts we present a framework with which to understand the varieties of outcomes an ebarts-based marketplace can achieve and how it can strategically exploit the changes such marketplaces may bring.