Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow

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

Extendable and Interchangeable Architecture Description of Distributed Systems Using UML and XML

Abstract. Software Architecture can help people to better understand the gross structure and, with powerful analysis techniques, to evaluate the properties of a software system. To accommodate the dynamic changes and facilitate interop-eration of tools, an architectural description of the distributed system should be extensible and interchangeable. In this paper, we utilize the built-in extension mechanism of the Unified Modeling Language (UML) to describe the architec-tures of distributed systems, with the underlying architectural metadata repre-sented in XML. In particular, the approach has been applied to describe the ar-chitectural model of distributed software in the Graph-Oriented Programming framework. The proposed approach has many desirable features, characterized by being visual, easily extendable and interchangeable, and well supported by tools.

Vorschlag für neue objektorientierte gleichungsbasierte Modellbibliotheken für thermodynamische Systeme

This thesis proposes two new model libraries for fluid properties and for components that can be used for the simulation of thermodynamic systems such as refrigeration, air-conditioning, and heat-pump systems. The new fluid property library is written in C/C++ and can be interfaced from various software tools and programming languages. The new component model library is written in the object-oriented equation-based modeling language Modelica. Furthermore, tools for the automated generation of class diagrams and the visualization of the solution process as well as the numerical results in relevant diagrams are presented. Both new libraries are based on a thorough object-oriented analysis. A set of general design rules for the development of object-oriented component model libraries is formulated to ensure that the resulting library can be used by the entire spectrum of possible users from experienced developers to design engineers. The new object-based fluid property library is based on a generalized approach to include external fluid property computation codes in Modelica. It is simple to extend to additional external fluid property computation codes. It allows for a numerically efficient handling of fluid properties in Modelica and in a number of software tools. The new model library for components and systems was developed based on the newly introduced design rules. It features a structure that is simple to understand and flexible to allow for extensions. All balance equations are formulated in an easy and comprehensible way in base components. The new component model library contains models with different levels of detail to allow for a problem-dependent model selection. Two applications are presented to demonstrate the capabilities of the two new libraries and to demonstrate their extendibility and multidisciplinarity.Diese Arbeit beschreibt zwei neue Modellbibliotheken mit Stoffdaten- und Komponentenmodellen zur Simulation thermodynamischer Systeme wie zum Beispiel Kälteanlagen, Klimaanlagen und Wärmepumpen. Die neue Stoffdatenbibliothek ist basierend auf C/C++ entwickelt worden und verfügt über Schnittstellen für unterschiedliche Anwendungsprogramme und Programmiersprachen. Die neue Komponentenbibliothek ist in der objektorientierten gleichungsbasierten Modellierungssprache Modelica geschrieben. Es werden außerdem Werkzeuge vorgestellt, die die automatische Generierung von Klassenstrukturdiagrammen und die Visualisierung des Lösungsprozesses sowie der numerischen Ergebnisse in thermodynamischen Diagrammen ermöglichen. Beide neuen Bibliotheken basieren auf einer gründlichen objektorientierten Analyse. Es werden des Weiteren allgemeingültige Richtlinien für die Erstellung von objektorientierten Modellbibliotheken entwickelt, die sicherstellen, dass die entwickelte Bibliothek das gesamte Spektrum möglicher Benutzer vom Code-Entwickler bis hin zum Anwender unterstützt. Die neue objektbasierte Stoffdatenbibliothek basiert auf einem generalisierten Ansatz zur Einbindung externer Stoffdatenbibliotheken in Modelica. Der beschriebene Ansatz lässt sich einfach auf weitere externe Bibliotheken zur Stoffdatenberechnung erweitern. Er erlaubt die numerisch effektive Behandlung der eingebundenen Bibliotheken in Modelica sowie in Anwendungsprogrammen. Die neue Modellbibliothek für Komponenten und Systeme verfügt über eine Struktur, die einfach verständlich und flexibel erweiterbar ist. Alle Erhaltungsgleichungen sind in einfach verständlicher Form in Basiskomponenten formuliert. Die neue Komponentenmodellbibliothek enthält Modelle unterschiedlicher Modellierungstiefe, um eine problemabhängige Auswahl von Modellen zu erlauben. Zwei Anwendungen für die beiden neuen Modellbibliotheken werden präsentiert, um die Erweiterbarkeit und die Multidisziplinarität der neuen Bibliotheken zu demonstrieren

The Unstoppable Rise of Computational Linguistics in Deep Learning

In this paper, we trace the history of neural networks applied to natural language understanding tasks, and identify key contributions which the nature of language has made to the development of neural network architectures. We focus on the importance of variable binding and its instantiation in attention-based models, and argue that Transformer is not a sequence model but an induced-structure model. This perspective leads to predictions of the challenges facing research in deep learning architectures for natural language understanding.Comment: 13 pages. Accepted for publication at ACL 2020, in the theme trac

A Catalog of Reusable Design Decisions for Developing UML/MOF-based Domain-specific Modeling Languages

In model-driven development (MDD), domain-specific modeling languages (DSMLs) act as a communication vehicle for aligning the requirements of domain experts with the needs of software engineers. With the rise of the UML as a de facto standard, UML/MOF-based DSMLs are now widely used for MDD. This paper documents design decisions collected from 90 UML/MOF-based DSML projects. These recurring design decisions were gained, on the one hand, by performing a systematic literature review (SLR) on the development of UML/MOF-based DSMLs. Via the SLR, we retrieved 80 related DSML projects for review. On the other hand, we collected decisions from developing ten DSML projects by ourselves. The design decisions are presented in the form of reusable decision records, with each decision record corresponding to a decision point in DSML development processes. Furthermore, we also report on frequently observed (combinations of) decision options as well as on associations between options which may occur within a single decision point or between two decision points. This collection of decision-record documents targets decision makers in DSML development (e.g., DSML engineers, software architects, domain experts).Series: Technical Reports / Institute for Information Systems and New Medi

Robotics Software Engineering: A Perspective from the Service Robotics Domain

Robots that support humans by performing useful tasks (a.k.a., service robots) are booming worldwide. In contrast to industrial robots, the development of service robots comes with severe software engineering challenges, since they require high levels of robustness and autonomy to operate in highly heterogeneous environments. As a domain with critical safety implications, service robotics faces a need for sound software development practices. In this paper, we present the first large-scale empirical study to assess the state of the art and practice of robotics software engineering. We conducted 18 semi-structured interviews with industrial practitioners working in 15 companies from 9 different countries and a survey with 156 respondents (from 26 countries) from the robotics domain. Our results provide a comprehensive picture of (i) the practices applied by robotics industrial and academic practitioners, including processes, paradigms, languages, tools, frameworks, and reuse practices, (ii) the distinguishing characteristics of robotics software engineering, and (iii) recurrent challenges usually faced, together with adopted solutions. The paper concludes by discussing observations, derived hypotheses, and proposed actions for researchers and practitioners.Comment: 11 pages + 1 page for references, 3 figures, 3 tables, in proceedings of ESEC/FSE 202