Quality-aware model-driven service engineering

Service engineering and service-oriented architecture as an integration and platform technology is a recent approach to software systems integration. Quality aspects ranging from interoperability to maintainability to performance are of central importance for the integration of heterogeneous, distributed service-based systems. Architecture models can substantially influence quality attributes of the implemented software systems. Besides the benefits of explicit architectures on maintainability and reuse, architectural constraints such as styles, reference architectures and architectural patterns can influence observable software properties such as performance. Empirical performance evaluation is a process of measuring and evaluating the performance of implemented software. We present an approach for addressing the quality of services and service-based systems at the model-level in the context of model-driven service engineering. The focus on architecture-level models is a consequence of the black-box character of services

Model-to-Model Transformation - From UML Class Diagrams to Labeled Property Graphs

Conceptual schemas are the basis to build well-grounded Information Systems, by representing the main concepts of a domain of knowledge, as well as the relationships among them. Since conceptual schemas focus on the concepts, they are independent of the specific technological platform used to implement them. This allows a single conceptual schema to be transformed into different platform-specific models according to the implementation requirements. This is a non-trivial process that is crucial for the performance and maintainability of the system, as well as for the accomplishment of the domain data requirements. Much research has been done on transforming conceptual schemas into relational data models. Nevertheless, less work has been done on transforming conceptual schemas into property graphs, a data structure indispensable to building appropriate and efficient systems based on graph databases. The work proposes a systematic approach to transform conceptual schemas, represented as UML class diagrams, into property graphs by using a set of transformation rules and patterns applied in a systematic way. Besides a practical example used to help the presentation of the proposed approach, the evaluation has been done by measuring different quality dimensions such as semantic equivalence, readability, maintainability, complexity, size, and performance

The Scalability-Efficiency/Maintainability-Portability Trade-off in Simulation Software Engineering: Examples and a Preliminary Systematic Literature Review

Large-scale simulations play a central role in science and the industry. Several challenges occur when building simulation software, because simulations require complex software developed in a dynamic construction process. That is why simulation software engineering (SSE) is emerging lately as a research focus. The dichotomous trade-off between scalability and efficiency (SE) on the one hand and maintainability and portability (MP) on the other hand is one of the core challenges. We report on the SE/MP trade-off in the context of an ongoing systematic literature review (SLR). After characterizing the issue of the SE/MP trade-off using two examples from our own research, we (1) review the 33 identified articles that assess the trade-off, (2) summarize the proposed solutions for the trade-off, and (3) discuss the findings for SSE and future work. Overall, we see evidence for the SE/MP trade-off and first solution approaches. However, a strong empirical foundation has yet to be established; general quantitative metrics and methods supporting software developers in addressing the trade-off have to be developed. We foresee considerable future work in SSE across scientific communities.Comment: 9 pages, 2 figures. Accepted for presentation at the Fourth International Workshop on Software Engineering for High Performance Computing in Computational Science and Engineering (SEHPCCSE 2016

Determination and evaluation of web accessibility

The Web is the most pervasive collaborative technology in widespread use today; however, access to the web and its many applications cannot be taken for granted. Web accessibility encompasses a variety of concerns ranging from societal, political, and economic to individual, physical, and intellectual through to the purely technical. Thus, there are many perspectives from which web accessibility can be understood and evaluated. In order to discuss these concerns and to gain a better understanding of web accessibility, an accessibility framework is proposed using as its base a layered evaluation framework from Computer Supported Co-operative Work research and the ISO standard, ISO/IEC 9126 on software quality. The former is employed in recognition of the collaborative nature of the web and its importance in facilitating communication. The latter is employed to refine and extend the technical issues and to highlight the need for considering accessibility from the viewpoint of the web developer and maintainer as well as the web user. A technically inaccessible web is unlikely to be evolved over time. A final goal of the accessibility framework is to provide web developers and maintainers with a practical basis for considering web accessibility through the development of a set of accessibility factors associated with each identified layer