UML is still inconsistent! How to improve OCL Constraints in the UML 2.3 Superstructure

Since the first OMG specification of the Unified Modeling Language (UML), the Object Constraint Language (OCL) has been used for the definition of well-formedness rules in the UML specification. These rules have been specified within the early OCL years, when no appropriate tooling existed. Thus, they could not be checked for syntactical and static semantics correctness. In this paper we present an analysis of the static correctness of all OCL rules specified in the UML 2.3 superstructure document. We categorise found errors and propose changes for both the UML specification process and the OCL language to improve the UML specification’s correctness in future versions

A Feature Model for an IDE4OCL

An Integrated OCL Development Environment (IDE4OCL) can significantly improve the pragmatics and practice of OCL. Therefore we started a comprehensive requirement analysis with the long term vision of a multisite IDE4OCL project. In this paper we present a feature model for the IDE4OCL vision based on this analysis. In an earlier work we identified domain concepts, tool–level interactions with IDE4OCL, and use cases for OCL developers including a set predefined features. In the second step, we asked the OCL community members for their feedback on our proposal. Around 100 researchers, tool developers and practitioners who gained experience with OCL have voted in an online–survey. The results gave us a valuable insight in the needs of OCL usage both in usual and advanced OCL applications. One of the important results is a collection of features that have been proposed additionally to our predefined features. We analysed all the comments of the participants of the survey and consolidated them into an extended set of IDE4OCL features and eventually into a feature model

A Framework for Generating Query Language Code from OCL Invariants

The semantical integrity of business data is of great importance for the implementation of business applications. Model-Driven Software Development (MDSD) allows for specifying the relevant domain concepts, their interrelations and their concise semantics using a plethora of modelling languages. Since model transformations enable an automatic mapping of platform independent models (PIMs) to platform specific models (PSMs) and code, it is reasonable to utilise them to derive data schemas and integrity rules for business applications. Most current approaches only focus on transforming structural descriptions of software systems while semantical specifications are neglected. However, to preserve also the semantical integrity rules we propose a Query Code Generation Framework that enables Model-Driven Integrity Engineering. This framework allows for mapping UML models to arbitrary data schemas and for mapping OCL invariants to sentences in corresponding declarative query languages, enforcing semantical data integrity on implementation level. This supersedes the manual translation of integrity constraints and, thus, decreases development costs while increasing software quality

Requirements Analysis for an Integrated OCL Development Environment

An Integrated OCL Development Environment (IDE4OCL) can significantly improve the pragmatics and praxis of OCL. We present the domain concepts, toolâlevel interactions with OCL and the use cases we identified in a systematic analysis of requirements for an IDE4OCL. The domain concepts is an important contribution of our work as it attempts to clarify inconsistencies in the relevant specifications. Because OCL is not a standâalone language, the OCL landscape includes several interacting tools including an IDE4OCL. The use cases describe our vision of the desired functionality unique to an IDE4OCL. The results of our analysis and the long term vision of our work should be relevant to developers of OCL tools as well as to the OMG Request for Information regarding the UML Futures1. Our work is relevant to the UML Futures Roadmap because providing OCL for the constraints in the UML specification has been a longstanding problem at the OMG

Risiken in der Softwareentwicklung

The overall costs of software production are of crucial importance to many companies, as software is involved in a constantly increasing number of business processes and products. On the other hand, the completion of software projects in accordance with defined quality, time and cost requirements involves a high level risk. This paper enumerates specific risks within software development, outlines possibilities for risk prevention and illustrates the treatment of risks within the software development process. The increasing application of software within embedded systems also founds a necessity of knowledge concerning the risks in software development for the established engineering disciplines.Die Kosten der Softwareproduktion sind für viele Firmen von entscheidender Bedeutung, da Software in einer ständig wachsenden Anzahl von Firmenprozessen und Produkten eingesetzt wird und immer mehr Anwendungsbereiche durchdringt. Allerdings birgt die qualitäts-, zeit- und kostengerechte Fertigstellung von Softwareprojekten enorme Risiken. Dieses Papier nennt spezifische Risiken der Softwareentwicklung anhand von fehlgeschlagenen Projekten, skizziert die Möglichkeiten der Risikovermeidung in der Softwareentwicklung und die Behandlung des Risikomanagements im Prozess der Softwareentwicklung. Der zunehmende Einsatz von Software in eingebetteten Systemen begründet die Notwendigkeit des Wissens um Risiken der Softwareentwicklung auch in den klassischen Ingenieurdisziplinen

Growth-based Theories for Declining Regions? A Note on Conceptualisations of Demographic Change for Regional Economic Development

This article aims to critically assess the economic growth paradigm, which typically underlies most approaches to regional policymaking for demographic change. While population losses, ageing and outmigration – i.e. phenomena that are addressed as demographic change – have become a matter of urgency for many European regions, most regional economic development theories remain silent about the population decline affecting the economic growth and development prospects of regions. Consequently, regional policies usually rely on the concept of economic growth, yet neglect the complexity and importance of demographic change and how it relates to the economic sphere. Due to this lack in nuance, we argue that regional policymaking fails to design adequate policy support for regions facing persistent demographic change and economic stagnation or decline as a result. Based on these observations, the paper examines a selection of regional economic development theories in search for alternative concepts of growth and development in the context of demographic change. To this aim, globalisation peripheries are introduced as a fruitful conceptual point of reference and, in combination with endogenous regional development theories, discussed as an alternative approach for regional policymaking.publishedVersio

Low molecular weight cellulose ethers as aerosols for the the consolidation of cohesively weak paint layers

Due to Edvard Munch’s (1863-1944) unconventional painting technique, choice of materials, and the unstable climate conditions of his studios, where the paintings were stored during his lifetime, many of his paintings, now housed at MUNCH, have cohesively weak and loose paint layers. As a result, consolidation and re-adhesion of these fragile paint layers are the most frequently performed conservation treatments on his paintings. A selection of low molecular weight (lmw) hydroxypropyl methylcellulose ethers (HPMC), new to the field of conservation, have been evaluated in comparison to methylcellulose (MC) A4C and sturgeon glue regarding their suitability for the consolidation of cohesively weak paint layers. The mock-ups used for these investigations were of a similar composition (pigment, binding medium and pigment-binding medium ratio) and porosity to a paint sample from the painting “Beach Landscape with Trees and Boats” from 1905-06 by Edvard Munch. Viscosity and surface tension of aqueous solutions of the consolidants and their influence on the imbibition time and depth into porous paint layers were investigated. Fluorescence labelling was used to visualize the imbibition depth of an aqueous solution of the lmw HPMC E3 and MC A4C, applied as an aerosol. With this method it could be shown that the applied amount and the application method of the consolidant (with or without intermediate drying steps) can play a crucial role in the imbibition depth. To evaluate the consolidation effect of the tested polymers, the aerosols of their aqueous solutions were applied on the paint mock-ups in a reproducible and standardized way, using an automated two-axis-table. A customised abrasion test was developed to evaluate the comparative increase of the paint layer cohesion after consolidation. These preliminary investigations show lmw HPMC as promising alternatives to established consolidants. They allow for an ultrasonic nebulisation in higher concentrations and thus for the paint layer’s consolidation in a lower number of applications

OCL Tools Report based on the IDE4OCL Feature Model

Previously we have developed the idea of an Integrated Development Environment for OCL (IDE4OCL). Based on the OCL community's feedback we have also designed and published an IDE4OCL feature model. Here we present a report on selected OCL tools developed by the authors and their teams. Each author gives an overview of their OCL tool, provides a top level architecture, and gives an evaluation of the tool features in a web framework. The framework can also be used by other potential OCL users and tool developers. For users it may serve as an aid to choose a suitable tool for their OCL use scenarios. For tool developers it provides a comparative view for further development of the OCL tools. Our plans are to maintain the collected data and extend this web framework by further OCL tools. Additionally, we would like to encourage sharing of OCL development resources

Report on the Aachen OCL meeting

As a continuation of the OCL workshop during the MODELS 2013 conference in October 2013, a number of OCL experts decided to meet in November 2013 in Aachen for two days to discuss possible short term improvements of OCL for an upcoming OMG meeting and to envision possible future long-term developments of the language. This paper is a sort of "minutes of the meeting" and intended to quickly inform the OCL community about the discussion topics