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Resources Events Agents (REA) ontology is a profound business modeling ontology that was developed to define the architecture of accounting information systems. Nevertheless, REA did not manage to get the same attention as other business modeling ontologies. One reason of such abandon is the absence of a meaningful visual notation for the ontology, which has resulted in an abstruse ontology to non-academic audience. Another reason for this abandon is the fact that REA does not have a standard formal representation. This has resulted in a humble amount of researches which have focused on defining meta-models of the ontology while neglecting the wider purpose of REA-based information systems development. Consequently, the ontology was deviated away from its original purpose, and rather used in business schools. To solve the aforementioned issues, this research presents a Model Driven Development (MDD) technique in the form of a REA-based Domain Specific Visual Language (DSVL) that is implemented within a modeling and code generation editor. This effort was taken in order to answer the question of “How would a REA-DSVL based tool make the REA ontology implementable in the domain of information systems development?” In order to answer the research question, a design science methodology (DSRM) was implemented as the structure of this research. The DSRM was chosen because this research aims to develop three main artifacts. These are; a meta-model of REA, a visual notation of REA, and a REA-DSVL-based modeling and code generation tool. The first phase of the DSRM was to identify the problems which were mentioned earlier, followed by the requirements identification phase which drew the outline of the; meta-model, the visual notation, and the tool. After that, the development phase was conducted in order to develop the aforementioned artifacts. The editor was then demonstrated using a case study of a local company in Stockholm-Sweden. Finally, the resulted artifacts were evaluated based on the collected requirements and the results from the case study. Based on the analyses of the artifacts and the case study, this research was concluded with the result that a REA-based DSVL tool can help in boosting the planning and analysis phases of the software development lifecycle (SDLC). This is achieved by automating some of the conventional software planning and design tasks, which would lead to more accurate systems’ designs; thus, minimizing the time of the planning and design phases. And it can be achieved by abstracting the direct logic of REA through providing functionalities that help users from different backgrounds (academic and professional) to embrace a business modeling editor rather than an ontology; thus, attracting a wider users base for implementing REA.

Indiana University-Purdue University Indianapolis (IUPUI) / This thesis investigates integrating recommender systems into model-driven engineering tools powered by domain-specific modeling languages. The objective of integrating recommender systems into such tools is overcome a shortcoming of proactive modeling where the modeler must inform the model intelligence engine how to progress when it cannot automatically determine the next modeling action to execute (e.g., add, delete, or edit). To evaluate our objective, we integrated a recommender system into the Proactive Modeling Engine, which is a add-on for the Generic Modeling Environment (GME). We then conducted experiments to both subjective and objectively evaluate the enhancements to the Proactive Modeling Engine. The results of our experiments show that integrating recommender system into the Proactive Modeling Engine results in an Average Reciprocal Hit-Rank (ARHR) of 0.871. Likewise, the integration results in System Usability Scale (SUS) rating of 77. Finally, user feedback shows that the integration of the recommender system to the Proactive Modeling Engine increases the usability and learnability of domain-speci c modeling tools.

Master of Science / Department of Computing and Information Sciences / John M. Hatcliff / Guardol, a domain-specific language (DSL) developed by Rockwell Collins, was designed to streamline the process of specifying, implementing, and verifying Cross Domain Solution (CDS) security policies. Guardol’s syntax and intended computational behavior tightly resembles the core of many functional programming languages, but a number of features have been added to ease the development of high assurance cross domain solutions. A significant portion of the formalization and implementation of Guardol’s grammar and type system was performed by the SAnToS group at Kansas State University. This report summarizes the key conceptual components of Guardol’s grammar and tool- chain architecture. The focus of the report is a detailed description of Guardol’s type system implementation and formalization. A great deal of effort was put into a formalization which provided a high level of assurance that the specification of types and data structures were maintained in the intended implementation.

Massively Parallel Processors provide significantly higher peak performance figures than other forms of general purpose processors. However, this comes at a cost to the developer, who needs to deal with an increasingly complicated piece of hardware, for which applications need to be tweaked and optimised to achieve high performance. Domain-specific languages have been proposed as a potential solution to this complexity problem: generating GPU applications from high-level, declarative specifications. This thesis explores two related ideas: firstly, is it practical to synthesise DSLs from high-level languages, and secondly, how can we simplify the creation of such DSLs? This thesis proposes a novel approach whereby rather than considering single domains, we consider collections of collaborative domains in order to share common features and thus reduce the cost of development. We achieve this using a DSLs-within-a-DSL approach: a custom designed host language, into which extensions may be embedded. In order to ground our approach in a real case-study, we propose, design and develop a DSLs-within-a-DSL framework for bioinformatics. We use a restricted recursive functional language as the host language, and embed new DSLs into this language. Importantly, we describe how we can use a combination of novel and adopted automatic parallelisation techniques to synthesise a massively-parallel program for a GPU. This automatic parallelisation, achieved through the discovery of a schedule, and program synthesis techniques using the polyhedral model, interacts productively with our embedded extensions. To further simplify development, we provide a series of customisable heuristics for defining GPU parameters such as the block size (number of threads), grid size and location in the memory hierarchy of data-structures. This encapsulates GPU expertise within the compiler itself. We finally demonstrate that the total combination of these techniques results in applications with competitive performance, at much lower development cost and greater flexibility than comparable hand-coded applications.

Numerous studies indicate that amongst the various types of security threats, the problem of insider misuse of IT systems can have serious consequences for the health of computing infrastructures. Although incidents of external origin are also dangerous, the insider IT misuse problem is difficult to address for a number of reasons. A fundamental reason that makes the problem mitigation difficult relates to the level of trust legitimate users possess inside the organization. The trust factor makes it difficult to detect threats originating from the actions and credentials of individual users. An equally important difficulty in the process of mitigating insider IT threats is based on the variability of the problem. The nature of Insider IT misuse varies amongst organizations. Hence, the problem of expressing what constitutes a threat, as well as the process of detecting and predicting it are non trivial tasks that add up to the multi- factorial nature of insider IT misuse. This thesis is concerned with the process of systematizing the specification of insider threats, focusing on their system-level detection and prediction. The design of suitable user audit mechanisms and semantics form a Domain Specific Language to detect and predict insider misuse incidents. As a result, the thesis proposes in detail ways to construct standardized descriptions (signatures) of insider threat incidents, as means of aiding researchers and IT system experts mitigate the problem of insider IT misuse. The produced audit engine (LUARM – Logging User Actions in Relational Mode) and the Insider Threat Prediction and Specification Language (ITPSL) are two utilities that can be added to the IT insider misuse mitigation arsenal. LUARM is a novel audit engine designed specifically to address the needs of monitoring insider actions. These needs cannot be met by traditional open source audit utilities. ITPSL is an XML based markup that can standardize the description of incidents and threats and thus make use of the LUARM audit data. Its novelty lies on the fact that it can be used to detect as well as predict instances of threats, a task that has not been achieved to this date by a domain specific language to address threats. The research project evaluated the produced language using a cyber-misuse experiment approach derived from real world misuse incident data. The results of the experiment showed that the ITPSL and its associated audit engine LUARM provide a good foundation for insider threat specification and prediction. Some language deficiencies relate to the fact that the insider threat specification process requires a good knowledge of the software applications used in a computer system. As the language is easily expandable, future developments to improve the language towards this direction are suggested.

Avec l’émergence de l’informatique dans les nuages, la capacité d’hébergement des centres de données ne cesse d’augmenter afin de répondre à une demande de plus en plus forte. La gestion, appelée l’administration, d’un centre de données entraîne des opérations fréquentes sur des machines virtuelles (VM) ainsi que sur des serveurs. De plus, chaque VM hébergée possède des besoins spécifiques au regard de sa qualité de service, de ses ressources et de son placement qui doit être compatible avec les mécanismes de tolérance aux pannes et la configuration réseau. Les outils de « l’Infrastructure As A Service » tels que Open Nebula et Vmware vSphere simplifient la création et le déploiement de VM. Cependant, l’administration d’une infrastructure virtualisée repose encore sur des changements manuels décidés par les administrateurs. Cette approche n’est plus pertinente pour la gestion d’infrastructures virtualisées de milliers de VM. En effet, les administrateurs ne peuvent pas manipuler des ensembles importants de VM tout en assurant la compatibilité des reconfigurations exécutées avec les besoins des VM. De nouvelles approches d’administration d’infrastructures proposent l’automatisation de certaines tâches d’administration. L’outil décrit dans ce document utilise des langages dédiés pour répondre aux besoins d’administration infrastructures virtualisées de taille conséquente. Dans un premier temps, l’outil propose aux administrateurs des opérations d’introspection pour observer l’organisation des ressources déployées sur l’infrastructure et les reconfigurations habituelles comme le démarrage, l’arrêt et le redémarrage de VM et de serveurs. Dans un second temps les administrateurs définissent le placement des VM à partir de règles de placement. À partir de ces règles, l’outil d’administration vérifie chaque reconfiguration et chaque ajout de règles exécutés par l’administrateur. Si une reconfiguration ou une règle est invalide, l’outil détecte un conflit et avertit l’administrateur de l’échec de l’opération. L’outil d’administration, à l’aide d’algorithmes d’ordonnancement peut calculer un plan de reconfigurations résolvant les conflits. Ces algorithmes peuvent aussi être utilisés pour mettre en place des politiques d’ordonnancement comme la consolidation ou l’équilibrage de charge. / With the emergence of cloud computing, the hosting capacity of the data centers has been continuously growing to support the non stop increasing clients demand. Managing a data center implies to regularly manipulate both virtual machines (VM) and servers. Each hosted VM has specific expectations regarding its quality of service, its resource requirements and its placement that may be compatible with fault tolerance mechanisms and the networking configuration. Infrastructure As A Service solutions such as Open Nebula and VMWare vSphere extremely simplify creations and deployments of VM but virtualized infrastructure management is still relying on manual changes on the environment. This approach is no longer compatible with an infrastructure composed of thousand of VM. Indeed, a system administrator can not manipulate a large set of VMinsuring that its reconfigurations are compatible with the expected VM requirements. This situation has led to new approaches for the infrastructure management employing automation to replace the traditional manual approach. The tool described in this document deals with VM management from Domain Specific Languages. On the one hand, this tool proposes to administrators introspection operations to monitor the infrastructure resources and common reconfigurations including starting, halting, rebooting, of serversand VM. On the other hand, administrators define the VM placement from placement rules. Then, the system checks, according to active rules, the validity of all reconfigurations and rules performed by administrators. If a reconfiguration or a rule is invalid, the administrative tool detects conflicts and warns administrators. To resolve a conflict, the system, by interacting with scheduling algorithms, computes a reconfiguration plan that satisfies all rules.The reconfiguration plan can also apply scheduling policies as consolidation or load balancing with respect to placement rules.

Les sciences qui traitent de la réalité, qu'elles soient naturelles, de la société ou de la vie, fonctionnent avec des modèles. Une partie de ces modèles décrivent les relations entre certaines grandeurs mesurables de la réalité, sans aller jusqu'au détail des interactions entre les éléments qui la composent. D'autres modèles décrivent ces interactions en prenant le point de vue des individus qui constituent le système, le comportement global n'est alors plus décrit à priori, mais observé à posteriori. Nous faisons le constat que dans les deux cas le scientifique a peu de liberté pour décrire les structures, en particulier spatiales, susceptibles de porter ces interactions. Nous proposons une approche de modélisation que l'on peut situer à mi-chemin entre les deux, et qui incite à étudier un système à travers la nature de ses interactions et des structures de graphes qui peuvent les porter. En plaçant au même niveau les relations spatiales, fonctionnelles, sociales ou hiérarchiques, nous tentons aussi de nous affranchir des contraintes induites par le choix effectué souvent à priori d'une forme de représentation de l'espace. Nous avons formalisé les concepts de base de cette approche, et ceux-ci ont constitué les éléments d'un langage métier, nommé Ocelet, que nous avons défini. Les outils permettant la mise en œuvre de ce langage ont été développés et intégrés sous la forme d'un environnement de modélisation et de simulation. Enfin nous avons pu expérimenter notre nouvelle approche de modélisation et le langage Ocelet à travers la réalisation de plusieurs modèles présentant des situations variées de dynamiques paysagères / Sciences dealing with reality be it related to nature, society or life, use models. Some of these models describe the relations that exist between measurable properties of that reality, without detailing the interactions between its components. Other models describe those interactions from the point of view of the individuals that form the system, in which case the overall behaviour is not defined a priori but observed a posteriori. In both cases, it can be noted that the scientist is often limited in its capacity to describe the structures, especially those spatial, which support the interactions. We propose a modelling approach that can be considered intermediate, where the system is studied by examining the nature of the interactions involved and the graph structures needed to support them. By unifying the description of spatial, functional, social or hierarchical relationships, we attempt to lift constraints induced by the form of spatial representation that are often chosen a priori. The basic concepts of this approach have been formalized, and were used to define and build a domain specific language, called Ocelet. The tools related to the implementation of the language have also been developed and assembled into an integrated modelling and simulation environment. It was then possible to experiment our new modelling approach and the Ocelet language by developing models for a variety of dynamic landscapes situations

Les langages dédiés (DSL) sont de plus en plus utilisés parce qu’ils permettent aux utilisateurs qui ne sont pas des experts en programmation d’exprimer des solutions avec des langages simples qui capturent l’expertise de leur domaine. C’est encore plus vrai pour les langages dédiés graphiques (DSML) qui ont un niveau d’abstraction plus élevé que les langages dédiés de programmation. Implémenter un DSML revient généralement à fournir un éditeur dédié qui permette aux utilisateurs de manipuler les abstractions de leur domaine (d’instancier le langage). Les expériences ont montré que l’implémentation d’un tel éditeur dédié graphique est coûteuse en termes de temps et de ressources humaines. Nous constatons que la plupart des plates-formes permettant de construire ce type d’éditeur (EMF/GMF, DSL Tools, Obeo Designer, ...) sont génériques. Elles essayent d’adresser le maximum de domaines possibles, ce qui les rend complexes et inadaptées à des cas d’utilisation spécifiques. Si la spécialisation aux domaines a été un succès pour les langages, pourquoi ne pas l’appliquer aux plates-formes de construction d’éditeurs ? Cela reviendrait à concevoir pour un domaine donné, une plate-forme permettant de construire facilement des éditeurs dédiés pour ce domaine. Cette plate-forme n’aurait pas les défauts d’une plate-forme totalement générique parce qu’elle serait restreinte au domaine ciblé. Ce type de plate-forme spécifique à un domaine, nous l’appelons Domain Specific Modeling Framework (DSMF). Le principal inconvénient d’un DSMF est qu’on ne peut l’utiliser que dans le cadre du domaine pour lequel il a été conçu. Cela implique qu’il faille construire un DSMF par domaine et c’est une solution coûteuse. Toutefois, nous pensons que cette approche sur les DSMF peut être généralisée afin d’adresser un grand nombre de domaines. Cette thèse a donc consisté à concevoir et à implanter un environnement qui permet de construire des DSMF de façon modulaire. / Domain Specific Languages (DSLs) are increasingly used in many fields as they allow users to express strategies without being programming experts. This is particularly true for graphical DSLs called Domain Specific Modeling Languages (DSMLs) which are more intuitive than programming DSLs. Implementing a DSML means providing a specific editor which allow users to express the language’s constructions (instantiate the language). Many experiments showed that implementing specific graphical editors is much manpower consuming. Our analysis is that most frameworks for building such editors (e.g. EMF/GMF) are generic, i.e. aim at fulfilling the requirements of any field, which leads to increased complexity and costs a lot in terms of development time. If domain specialization was successful for languages, why don’t we apply it to frameworks ? Specializing such a framework according to the constraints of a domain would allow keeping the definition of a specific editor simple, while fulfilling the requirements of the considered domain. Domain specific frameworks for building DSML editors in specific application fields is a promising approach. Such a framework does not have the limits of generic frameworks because it is restricted to a particular domain. It is more intuitive and simpler to use as it only proposes abstraction of the domain for building DSMLs. We call this type of framework Domain Specific Modeling Framework (DSMF). For example, if we consider the component domain, there are several DSMLs in this domain which share the same layout requirements. We implemented a DSMF for this family of DSMLs. This DSMF is specialized according to the constraints and layout requirements of the component domain (Components, connectors, Bindings, . . .). This specialization allows simple and rapid generation of specific editors devoted to component-based architectures. The principal drawback of a DSMF is its restricted scope to one specific domain. This approach requires to develop one DSMF per domain and the development cost can be significant. A solution may be to generalise the DSMF approach in order to address many application fields. We designed a Generic framework for building DSMFs in a modular way. This thesis is based on the implementation of this framework.

La programmation par contraintes est souvent décrite, utopiquement, comme un paradigme déclaratif dans lequel l’utilisateur décrit son problème et le solveur le résout. Bien entendu, la réalité des solveurs de contraintes est plus complexe, et les besoins de personnalisation des techniques de modélisation et de résolution évoluent avec le degré d’expertise des utilisateurs. Cette thèse porte sur l’enrichissement de l’arsenal des techniques disponibles dans les solveurs de contraintes. D’une part, nous étudions la contribution d’un système d’explications à l’exploration de l’espace de recherche, dans le cadre spécifique d’une recherche locale. Deux heuristiques de voisinages génériques exploitant singulièrement les explications sont décrites. La première se base sur la difficulté de réparer une solution partiellement détruite, la seconde repose sur la nature non-optimale de la solution courante. Ces heuristiques mettent à jour la structure interne des problèmes traités pour construire des voisins de bonne qualité pour une recherche à voisinage large. Elles sont complémentaires d’autres heuristiques de voisinages génériques, avec lesquels elles peuvent être combinées efficacement. De plus, nous proposons de rendre le système d’explications paresseux afin d’en minimiser l’empreinte. D’autre part, nous effectuons un état des lieux des savoir-faire relatifs aux moteurs de propagation pour les solveurs de contraintes. Ces données sont exploitées opérationnellement à travers un langage dédié qui permet de personnaliser la propagation au sein d’un solveur, en fournissant des structures d’implémentation et en définissant des points de contrôle dans le solveur. Ce langage offre des concepts de haut niveau permettant à l’utilisateur d’ignorer les détails de mise en œuvre du solveur, tout en conservant un bon niveau de flexibilité et certaines garanties. Il permet l’expression de schémas de propagation spécifiques à la structure interne de chaque problème. La mise en œuvre et les expérimentations ont été effectués dans le solveur de contraintes Choco. Cette thèse a donné lieu à une nouvelle version de l’outil globalement plus efficace et nativement expliqué. / Constraint programming is often described, idealistically, as a declarative paradigm in which the user describes the problem and the solver solves it. Obviously, the reality of constraint solvers is more complex, and the needs in customization of modeling and solving techniques change with the level of expertise of users. This thesis focuses on enriching the arsenal of available techniques in constraint solvers. On the one hand, we study the contribution of an explanation system to the exploration of the search space in the specific context of a local search. Two generic neighborhood heuristics which exploit explanations singularly are described. The first one is based on the difficulty of repairing a partially destroyed solution, the second one is based on the non-optimal nature of the current solution. These heuristics discover the internal structure of the problems to build good neighbors for large neighborhood search. They are complementary to other generic neighborhood heuristics, with which they can be combined effectively. In addition, we propose to make the explanation system lazy in order to minimize its footprint. On the other hand, we undertake an inventory of know-how relative to propagation engines of constraint solvers. These data are used operationally through a domain specific language that allows users to customize the propagation schema, providing implementation structures and defining check points within the solver. This language offershigh-level concepts that allow the user to ignore the implementation details, while maintaining a good level of flexibility and some guarantees. It allows the expression of propagation schemas specific to the internal structure of each problem solved. Implementation and experiments were carried out in the Choco constraint solver, developed in this thesis. This has resulted in a new version of the overall effectiveness and natively explained tool.