Tools for producing formal specifications : a view of current architectures and future directions

During the last decade, one important contribution towards requirements engineering has been the advent of formal specification languages. They offer a well-defined notation that can improve consistency and avoid ambiguity in specifications. However, the process of obtaining formal specifications that are consistent with the requirements is itself a difficult activity. Hence various researchers are developing systems that aid the transition from informal to formal specifications. The kind of problems tackled and the contributions made by these proposed systems are very diverse. This paper brings these studies together to provide a vision for future architectures that aim to aid the transition from informal to formal specifications. The new architecture, which is based on the strengths of existing studies, tackles a number of key issues in requirements engineering such as identifying ambiguities, incompleteness, and reusability. The paper concludes with a discussion of the research problems that need to be addressed in order to realise the proposed architecture

Flexible Views for View-based Model-driven Development

Modern software development faces the problem of fragmentation of information across heterogeneous artefacts in different modelling and programming languages. In this dissertation, the Vitruvius approach for view-based engineering is presented. Flexible views offer a compact definition of user-specific views on software systems, and can be defined the novel ModelJoin language. The process is supported by a change metamodel for metamodel evolution and change impact analysis

A Model Driven Approach to Model Transformations

The OMG's Model Driven Architecture (MDA) initiative has been the focus of much attention in both academia and industry, due to its promise of more rapid and consistent software development through the increased use of models. In order for MDA to reach its full potential, the ability to manipulate and transform models { most obviously from the Platform Independent Model (PIM) to the Platform Specific Models (PSM) { is vital. Recognizing this need, the OMG issued a Request For Proposals (RFP) largely concerned with finding a suitable mechanism for trans- forming models. This paper outlines the relevant background material, summarizes the approach taken by the QVT-Partners (to whom the authors belong), presents a non-trivial example using the QVT-Partners approach, and finally sketches out what the future holds for model transformations

Formal transformation methods for automated fault tree generation from UML diagrams

With a growing complexity in safety critical systems, engaging Systems Engineering with System Safety Engineering as early as possible in the system life cycle becomes ever more important to ensure system safety during system development. Assessing the safety and reliability of system architectural design at the early stage of the system life cycle can bring value to system design by identifying safety issues earlier and maintaining safety traceability throughout the design phase. However, this is not a trivial task and can require upfront investment. Automated transformation from system architecture models to system safety and reliability models offers a potential solution. However, existing methods lack of formal basis. This can potentially lead to unreliable results. Without a formal basis, Fault Tree Analysis of a system, for example, even if performed concurrently with system design may not ensure all safety critical aspects of the design. [Continues.]</div

Traceability support in software product lines

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Informática.Traceability is becoming a necessary quality of any modern software system. The complexity in modern systems is such that, if we cannot rely on good techniques and tools it becomes an unsustainable burden, where software artifacts can hardly be linked to their initial requirements. Modern software systems are composed by a many artifacts (models, code, etc.). Any change in one of them may have repercussions on many components. The assessment of this impact usually comes at a high cost and is highly error-prone. This complexity inherent to software development increases when it comes to Software Product Line Engineering. Traceability aims to respond to this challenge, by linking all the software artifacts that are used, in order to reason about how they influence each others. We propose to specify, design and implement an extensible Traceability Framework that will allow developers to provide traceability for a product line, or the possibility to extend it for other development scenarios. This MSc thesis work is to develop an extensible framework, using Model-Driven techniques and technologies, to provide traceability support for product lines. We also wish to provide basic and advanced traceability queries, and traceability views designed for the needs of each user

Semantic metadata for supporting exploratory OLAP

Cotutela Universitat Politècnica de Catalunya i Aalborg UniversitetOn-Line Analytical Processing (OLAP) is an approach widely used for data analysis. OLAP is based on the multidimensional (MD) data model where factual data are related to their analytical perspectives called dimensions and together they form an n-dimensional data space referred to as data cube. MD data are typically stored in a data warehouse, which integrates data from in-house data sources, and then analyzed by means of OLAP operations, e.g., sales data can be (dis)aggregated along the location dimension. As OLAP proved to be quite intuitive, it became broadly accepted by non-technical and business users. However, as users still encountered difficulties in their analysis, different approaches focused on providing user assistance. These approaches collect situational metadata about users and their actions and provide suggestions and recommendations that can help users' analysis. However, although extensively exploited and evidently needed, little attention is paid to metadata in this context. Furthermore, new emerging tendencies call for expanding the use of OLAP to consider external data sources and heterogeneous settings. This leads to the Exploratory OLAP approach that especially argues for the use of Semantic Web (SW) technologies to facilitate the description and integration of external sources. With data becoming publicly available on the (Semantic) Web, the number and diversity of non-technical users are also significantly increasing. Thus, the metadata to support their analysis become even more relevant. This PhD thesis focuses on metadata for supporting Exploratory OLAP. The study explores the kinds of metadata artifacts used for the user assistance purposes and how they are exploited to provide assistance. Based on these findings, the study then aims at providing theoretical and practical means such as models, algorithms, and tools to address the gaps and challenges identified. First, based on a survey of existing user assistance approaches related to OLAP, the thesis proposes the analytical metadata (AM) framework. The framework includes the definition of the assistance process, the AM artifacts that are classified in a taxonomy, and the artifacts organization and related types of processing to support the user assistance. Second, the thesis proposes a semantic metamodel for AM. Hence, Resource Description Framework (RDF) is used to represent the AM artifacts in a flexible and re-usable manner, while the metamodeling abstraction level is used to overcome the heterogeneity of (meta)data models in the Exploratory OLAP context. Third, focusing on the schema as a fundamental metadata artifact for enabling OLAP, the thesis addresses some important challenges on constructing an MD schema on the SW using RDF. It provides the algorithms, method, and tool to construct an MD schema over statistical linked open data sets. Especially, the focus is on enabling that even non-technical users can perform this task. Lastly, the thesis deals with queries as the second most relevant artifact for user assistance. In the spirit of Exploratory OLAP, the thesis proposes an RDF-based model for OLAP queries created by instantiating the previously proposed metamodel. This model supports the sharing and reuse of queries across the SW and facilitates the metadata preparation for the assistance exploitation purposes. Finally, the results of this thesis provide metadata foundations for supporting Exploratory OLAP and advocate for greater attention to the modeling and use of semantics related to metadata.El processament analític en línia (OLAP) és una tècnica àmpliament utilitzada per a l'anàlisi de dades. OLAP es basa en el model multi-dimensional (MD) de dades, on dades factuals es relacionen amb les seves perspectives analítiques, anomenades dimensions, i conjuntament formen un espai de dades n-dimensional anomenat cub de dades. Les dades MD s'emmagatzemen típicament en un data warehouse (magatzem de dades), el qual integra dades de fonts internes, les quals posteriorment s'analitzen mitjançant operacions OLAP, per exemple, dades de vendes poden ser (des)agregades a partir de la dimensió ubicació. Un cop OLAP va ser provat com a intuïtiu, va ser ampliament acceptat tant per usuaris no tècnics com de negoci. Tanmateix, donat que els usuaris encara trobaven dificultats per a realitzar el seu anàlisi, diferents tècniques s'han enfocat en la seva assistència. Aquestes tècniques recullen metadades situacionals sobre els usuaris i les seves accions, i proporcionen suggerències i recomanacions per tal d'ajudar en aquest anàlisi. Tot i ésser extensivament emprades i necessàries, poca atenció s'ha prestat a les metadades en aquest context. A més a més, les noves tendències demanden l'expansió d'ús d'OLAP per tal de considerar fonts de dades externes en escenaris heterogenis. Això ens porta a la tècnica d'OLAP exploratori, la qual es basa en l'ús de tecnologies en la web semàntica (SW) per tal de facilitar la descripció i integració d'aquestes fonts externes. Amb les dades essent públicament disponibles a la web (semàntica), el nombre i diversitat d'usuaris no tècnics també incrementa signifícativament. Així doncs, les metadades per suportar el seu anàlisi esdevenen més rellevants. Aquesta tesi doctoral s'enfoca en l'ús de metadades per suportar OLAP exploratori. L'estudi explora els tipus d'artefactes de metadades utilitzats per l'assistència a l'usuari, i com aquests són explotats per proporcionar assistència. Basat en aquestes troballes, l'estudi preté proporcionar mitjans teòrics i pràctics, com models, algorismes i eines, per abordar els reptes identificats. Primerament, basant-se en un estudi de tècniques per assistència a l'usuari en OLAP, la tesi proposa el marc de treball de metadades analítiques (AM). Aquest marc inclou la definició del procés d'assistència, on els artefactes d'AM són classificats en una taxonomia, i l'organització dels artefactes i tipus relacionats de processament pel suport d'assistència a l'usuari. En segon lloc, la tesi proposa un meta-model semàntic per AM. Així doncs, s'utilitza el Resource Description Framework (RDF) per representar els artefactes d'AM d'una forma flexible i reusable, mentre que el nivell d'abstracció de metamodel s'utilitza per superar l'heterogeneïtat dels models de (meta)dades en un context d'OLAP exploratori. En tercer lloc, centrant-se en l'esquema com a artefacte fonamental de metadades per a OLAP, la tesi adreça reptes importants en la construcció d'un esquema MD en la SW usant RDF. Proporciona els algorismes, mètodes i eines per construir un esquema MD sobre conjunts de dades estadístics oberts i relacionats. Especialment, el focus rau en permetre que usuaris no tècnics puguin realitzar aquesta tasca. Finalment, la tesi tracta amb consultes com el segon artefacte més rellevant per l'assistència a usuari. En l'esperit d'OLAP exploratori, la tesi proposa un model basat en RDF per consultes OLAP instanciant el meta-model prèviament proposat. Aquest model suporta el compartiment i reutilització de consultes sobre la SW i facilita la preparació de metadades per l'explotació de l'assistència. Finalment, els resultats d'aquesta tesi proporcionen els fonaments en metadades per suportar l'OLAP exploratori i propugnen la major atenció al model i ús de semàntica relacionada a metadades.On-Line Analytical Processing (OLAP) er en bredt anvendt tilgang til dataanalyse. OLAP er baseret på den multidimensionelle (MD) datamodel, hvor faktuelle data relateres til analytiske synsvinkler, såkaldte dimensioner. Tilsammen danner de et n-dimensionelt rum af data kaldet en data cube. Multidimensionelle data er typisk lagret i et data warehouse, der integrerer data fra forskellige interne datakilder, og kan analyseres ved hjælp af OLAPoperationer. For eksempel kan salgsdata disaggregeres langs sted-dimensionen. OLAP har vist sig at være intuitiv at forstå og er blevet taget i brug af ikketekniske og orretningsorienterede brugere. Nye tilgange er siden blevet udviklet i forsøget på at afhjælpe de problemer, som denne slags brugere dog stadig står over for. Disse tilgange indsamler metadata om brugerne og deres handlinger og kommer efterfølgende med forslag og anbefalinger, der kan bidrage til brugernes analyse. På trods af at der er en klar nytteværdi i metadata (givet deres udbredelse), har stadig ikke været meget opmærksomhed på metadata i denne kotekst. Desuden lægger nye fremspirende teknikker nu op til en udvidelse af brugen af OLAP til også at bruge eksterne og uensartede datakilder. Dette har ført til Exploratory OLAP, en tilgang til OLAP, der benytter teknologier fra Semantic Web til at understøtte beskrivelse og integration af eksterne kilder. Efterhånden som mere data gøres offentligt tilgængeligt via Semantic Web, kommer flere og mere forskelligartede ikketekniske brugere også til. Derfor er metadata til understøttelsen af deres dataanalyser endnu mere relevant. Denne ph.d.-afhandling omhandler metadata, der understøtter Exploratory OLAP. Der foretages en undersøgelse af de former for metadata, der benyttes til at hjælpe brugere, og af, hvordan sådanne metadata kan udnyttes. Med grundlag i disse fund søges der løsninger til de identificerede problemer igennem teoretiske såvel som praktiske midler. Det vil sige modeller, algoritmer og værktøjer. På baggrund af en afdækning af eksisterende tilgange til brugerassistance i forbindelse med OLAP præsenteres først rammeværket Analytical Metadata (AM). Det inkluderer definition af assistanceprocessen, en taksonomi over tilhørende artefakter og endelig relaterede processeringsformer til brugerunderstøttelsen. Dernæst præsenteres en semantisk metamodel for AM. Der benyttes Resource Description Framework (RDF) til at repræsentere AM-artefakterne på en genbrugelig og fleksibel facon, mens metamodellens abstraktionsniveau har til formål at nedbringe uensartetheden af (meta)data i Exploratory OLAPs kontekst. Så fokuseres der på skemaet som en fundamental metadata-artefakt i OLAP, og afhandlingen tager fat i vigtige udfordringer i forbindelse med konstruktionen af multidimensionelle skemaer i Semantic Web ved brug af RDF. Der præsenteres algoritmer, metoder og redskaber til at konstruere disse skemaer sammenkoblede åbne statistiske datasæt. Der lægges særlig vægt på, at denne proces skal kunne udføres af ikke-tekniske brugere. Til slut tager afhandlingen fat i forespørgsler som anden vigtig artefakt inden for bruger-assistance. I samme ånd som Exploratory OLAP foreslås en RDF-baseret model for OLAP-forespørgsler, hvor førnævnte metamodel benyttes. Modellen understøtter deling og genbrug af forespørgsler over Semantic Web og fordrer klargørelsen af metadata med øje for assistance-relaterede formål. Endelig leder resultaterne af afhandlingen til fundamenterne for metadata i støttet Exploratory OLAP og opfordrer til en øget opmærksomhed på modelleringen og brugen af semantik i forhold til metadataPostprint (published version

JAMDER: JADE to MULTI-Agent Systems Development Resource

The semantic gap is distinguished by the difference between two descriptions generated using different representations. This difference has a negative impact on the developer productivity and probably, the quality of the written code. In software development context, the coding phase aims at coding the system consistent with the detailed project developed with a group of designed models. This paper presents an endeavor to consolidate different agent type definitions and implementation concepts for Multi-Agent Systems (MAS) involving the adaptation of the JADE framework regarding the theoretical concepts in MAS. Additionally, it contains a standardization of code generation. The main benefit of the proposed extension is to include the agent internal architectures, entities and relationships in an implementation framework and increase the productivity by code generation, ensuring the consistency between design and code. The applicability of the extension is illustrated by developing a multi-agent system for Moodle

MINERVA : Model drIveN and sErvice oRiented framework for the continuous improVement of business process & relAted tools

Organizations are facing several challenges nowadays, one of the most important ones being their ability to react quickly to changes either to their business process (BP) models or to the software implementing them. These changes can come from different sources: external requirements from partners or the market, or new internal requirements for the way that things are carried out by the defined BPs; they may also arise from improvement opportunities detected for the BPs defined, based on BPs execution monitoring and execution evaluation that is done by the organization, and/or its partners and customers. The increasing complexity of both BPs models and the software implementing them, requires the changes needed or the improvements to be carefully weighed against the impact their introduction will have; they ought also to be carried out in a systematic way to assure a successful development. Two key elements are to provide these requirements: the separation of BPs definition from their implementation to minimize the impact of changes in one to the other, and a process to introduce the changes or improvements in the existing BPs and/or software implementing them. Business Process Management (BPM) provides the means for guiding and supporting the modeling, implementation, deployment, execution and evaluation of BPs in an organization, based on the BP lifecycle. The realization of BPs by means of services provides the basis for separating their definition from the technologies implementing them and helps provide a better response to changes in either of the layers defined -definition and implementation of business processes- with minimum impact on the other. Modeling of both BP and services is a key aspect to support this vision, helping provide traceability between elements from one area to the other, so easing the analysis of the impact of changes, among other things. Models have proven to play an important role in the software development process, one of its key uses in the context of BP realization by means of services is that of designing services at a more abstract level than with specific technologies, also promoting reuse by separating services logic from its implementation. MINERVA: Model drIveN & sErvice oRiented framework for the continuous business process improVement & relAted tools is the framework that has been defined in this thesis work; it takes into account all the aspects mentioned, in which the SOC and MDD paradigms are applied to BPs focusing on their continuous improvement, extending an existing BP lifecycle with explicit execution measurement and improvement activities and elements. It is made up of three dimensions: i) conceptual, which defines the concepts that are managed throughout the framework. ii) methodological, which defines a methodology for service oriented development from BPs with automatic generation of SoaML service models from BPMN2 models, along with a continuous improvement process based on execution measurement of the occurrences of BPs in the organization to carry out the improvement effort. iii) tools support for the whole proposal based on several existing tools we have integrated, along with new ones we have developed. The proposals in MINERVA have been validated by means of an experiment and two case studies carried out in the context of real projects in two organizations, from which, as the main result of the applications performed, it can be concluded that MINERVA can be a useful and key guide for the continuous improvement of BPs realized by services and for the development of service oriented systems from BPs, with automatic generation of service models from BP models.Las organizaciones se enfrentan en la actualidad a varios retos, siendo uno de los más importantes su capacidad para reaccionar rápidamente a los cambios ya sea en sus modelos de procesos de negocio (PN) o en el software que los implementa. Estos cambios pueden provenir de distintas fuentes: requisitos externos de socios o del mercado, o nuevos requisitos internos para la forma en que las cosas se llevan a cabo por los PNs definidos; también pueden surgir de las oportunidades de mejora detectadas para los PNs definidos, en base al monitoreo y evaluación de la ejecución de los PNs llevada a cabo por la organización, y/o sus socios y clientes. La creciente complejidad de los modelos de PNs y del software que los implementa, requiere que los cambios o las mejoras sean sopesados cuidadosamente contra el impacto que su introducción tendrá; también deben llevarse a cabo de manera sistemática para asegurar un desarrollo exitoso. Dos elementos son clave para proveer estos requisitos: la separación de la definición de los PNs de su implementación, para minimizar el impacto de los cambios de uno en otro, y un proceso para introducir los cambios o mejoras en los PNs y/o en el software que los implementa. La Gestión de Procesos de Negocio (Business Process Management, BPM) proporciona los medios para guiar y apoyar el modelado, implementación, despliegue, ejecución y evaluación de PNs en una organización, basado en el ciclo de vida de PNs. La realización de PNs con servicios proporciona la base para la separación de su definición de las tecnologías para implementarlos, y ayuda a proporcionar una mejor respuesta a los cambios en cualquiera de las capas definidas -definición e implementación de procesos de negocio- con un impacto mínimo sobre la otra. El modelado de PNs y servicios es un aspecto clave para apoyar esta visión, ayudando a proveer trazabilidad entre los elementos de un área a la otra, por lo tanto facilitando el análisis del impacto de los cambios, entre otras cosas. Los modelos han demostrado jugar un papel importante en el proceso de desarrollo de software, uno de sus usos principales en el contexto de la realización de PNs con servicios es el de diseñar servicios a un nivel más abstracto que con tecnologías específicas, promoviendo la reutilización separando la lógica de los servicios de su implementacion. MINERVA: Model drIveN & sErvice oRiented framework for the continuous business process improVement & relAted tools es el marco que se ha definido en este trabajo de tesis, que toma en cuenta todos los aspectos mencionados, en el cual los paradigmas de Computación Orientada a Servicios (Service Oriented Computing, SOC) y Desarrollo Dirigido por Modelos (Model Driven Development, MDD) se aplican a los PNs con foco en su mejora continua, extendiendo un ciclo de vida PN existente con actividades y elementos explícitos para la medición de la ejecución y mejora de PNs. El marco se compone de tres dimensiones: i) conceptual, que define los conceptos que se manejan en todo el marco. ii) metodológica, que define una metodología para el desarrollo orientado a servicios desde PNs, con generación automática de modelos de servicio en SoaML desde modelos en BPMN2, junto con un proceso de mejora continua basado en la medición de la ejecución de las ocurrencias de los PNs en la organización para llevar a cabo el esfuerzo de mejora. iii) soporte de herramientas para la propuesta completa basado en la integracion de varias herramientas existentes, junto con otras nuevas que hemos desarrollado. Las propuestas de MINERVA han sido validadas por medio de un experimento y dos casos de estudio realizados en el marco de proyectos reales en dos organizaciones, de los cuales, como resultado principal de las aplicaciones realizadas, se puede concluir que MINERVA puede ser una guía útil y clave para la mejora continua de PNs realizados por servicios y para el desarrollo de sistemas orientados a servicios desde PNs, con generación automática de modelos de servicio a partir de modelos de PN