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Software has emerged as a significant part of many domains, including financial service platforms, social networks, medical devices and vehicle control. In critical domains, standards organizations have responded to this by creating regulations to address issues such as safety, security and privacy. In this context, compliance of software with standards has emerged as a key issue. For companies, compliance is a complex and costly goal to achieve and is often accomplished by producing so-called assurance cases, which demonstrate that the system indeed satisfies the property imposed by a standard (e.g., safety, security, privacy) by linking evidence to support claims made about the system. However, as systems undergo evolution for a variety of reasons, including fixing bugs, adding functionality or improving system quality, maintaining assurance cases multiplies the effort. Increasingly, models and model-driven engineering are being used as a means to facilitate communication and collaboration between the stakeholders in the compliance value chain and, further, to introduce automation into regulatory compliance tasks. A complexity problem also exists with the proliferation of software models in model-based software development, and the field of Model Management has emerged to address this challenge. Model Management focuses on a high-level view in which entire models and their relationships (i.e., mappings between models) can be manipulated using specialized operators to achieve useful outcomes. In this thesis, we exploit this connection between model driven engineering and regulatory compliance, and explore how to use Model Management techniques to address software compliance management issues, focusing on assurance case change impact assessment, evolution and reuse. We support the presented approach with tooling and a case study. Although the main contributions of this thesis are not domain specific, for validation, we ground our approaches in the automotive domain and the ISO 26262 standard for functional safety of road vehicles. / Thesis / Doctor of Philosophy (PhD)

Due to the ever increasing complexity of safety-critical applications, handwritten code is being replaced by automatically generated code derived from a high level specification. Code generation from high level specification requires a model of computation with an underlying formalism and correctness-preserving refinement steps to generate the lower level application code. Such software synthesis techniques are said to be 'correct-by-construction'. Synchronous programming languages such as Esterel, LUSTRE, which are based on a synchronous model of computation are used for sequential code generation. They work on a synchrony assumption (zero time intraprocess computation and zero time inter process communication) at the specification level. Early versions of synchronous languages followed an execution pattern where an iteration of software was mapped to an interval between ticks of an external reference clock. Since this external reference tick was unrelated to variables (or signals) within the software, redundant operations such as reading of ports, computation of guards were performed for each tick. In this dissertation, we highlight some of these performance issues and missed optimization opportunities. Also we show how a multi-clock (or polychronous) formalism, where each variable has an independent rate of execution associated with it, can avoid these problems. An existing polychronous language named SIGNAL, creates a hierarchy of clocks based on the rate of execution of individual variables, to form a root clock which acts a reference tick. We seek to replace the clock analysis with a technique to form a unique order of events without a reference time line. For this purpose, we present a new polychronous formalism termed Multi-rate Instantaneous Channel connected Data Flow (MRICDF). Our new synthesis technique inspects the specification to identify a master trigger at a Boolean equation level to act as the reference tick. Furthermore, we attempt to make polychronous specification based software synthesis more accessible to practicing engineers, by constructing a software tool EmCodeSyn, with a visual environment for specification and a more intuitive analysis technique. Our Boolean approach to sequential synthesis of embedded software has multiple implementations, each of which utilizes existing academic software tools. Optimizations are proposed to minimize synthesis time by simplifying the input to these external tools. Weaknesses in causal loop analysis techniques applied by existing synthesis tools are highlighted and solutions for performing time efficient loop analysis are integrated into EmCodeSyn. We have also determined that a part of the non-synthesizable polychronous specifications can be used to generate correct multi-threaded code. Additionally, we investigate composition of polychronous modules and propose properties that are necessary to guarantee agreement on shared signals. / Ph. D.

This dissertation addresses two important problems in reusing intellectual properties (IPs) in the form of reusable design or verification components. The first problem is associated with fast and effective integration of reusable design components into a System-on-chip (SoC), so faster design turn-around time can be achieved, leading to faster time-to-market. The second problem has the same goals of faster product design cycle, but emphasizes on verification model reuse, rather than design component reuse. It specifically addresses reuse of reusable verification IPs to enable a "write once, use many times" verification strategy. This dissertation is accordingly divided into part I and part II which are related but describe the two problems and our solutions to them. These two related but distinctive problems faced by system design companies have been tackled through a unique approach which hither-to-fore only have been used in the software engineering domain. This approach is called metamodeling, which allows creating customized meta-language to describe the syntax and semantics for a modeling domain. It provides a way to create, transform and analyze domain specific languages, which are themselves described by metamodels, and the transformation and processing of models in such languages are also described by metamodels. This makes machine based interpretation and translation from these models an easier and formal task. In part I, we consider the problem of rapid system-level model integration of existing reusable components such that (i) the required architecture of the SoC can be expressed formally, (ii) automatic selection of components from an IP library to match the need of the system being integrated can be done, (iii) integrability of the components is provable, or checkable automatically, and (iv) structural and behavioral type systems for each component can be utilized through inferencing and matching techniques to ensure their compatibility. Our solutions include a component composition language, algorithms for component selection, type matching and inferencing algorithms, temporal property based behavioral typing, and finally a software system on top of an existing metamodeling environment. In part II, we use the same metamodeling environment to create a framework for modeling generative verification IPs. Our main contributions relate to INTEL's microprocessor verification environment, and our solution spans various abstraction levels (System, architectural, and microarchitecture) to perform verification. We provide a unified language that can be used to model verification IPs at all abstraction levels, and verification collaterals such as testbenches, simulators, and coverage monitors can be generated from these models, thereby enhancing reuse in verification. / Ph. D.

La visión de la "Internet de las Cosas", hace énfasis en la integración entre elementos del mundo real y los Sistemas de Información. Gracias a tecnologías de Identificación Automática (Auto-ID) cómo RFID, los sistemas pueden percibir objetos del mundo físico. Cuando éstos participan de manera activa en los procesos de negocio, se evita el uso de los seres humanos como transportadores de información. Por tanto, el número de errores se reduce y la eficiencia de los procesos aumenta. Aunque actualmente ya es posible el desarrollo de estos sistemas, la heterogeneidad tecnológica en Auto-ID y los requisitos cambiantes de los procesos de negocio dificultan su construcción, mantenimiento y evolución. Por lo tanto, es necesaria la definición de soluciones que afronten la construcción de estos sistemas mediante métodos sólidos de desarrollo para garantizar la calidad final del producto. Partiendo de las bases de la Ingeniería Dirigida por Modelos (MDE), esta tesis presenta un proceso de desarrollo para la construcción de este tipo de sistemas. Este proceso cubre desde la especificación del sistema hasta su implementación, centrándose en los requisitos particulares del enlace entre los mundos físico y virtual. Para la especificación de los sistemas se ha definido un Lenguaje de modelado adaptado a los requisitos de la "Internet de las Cosas". A partir de esta especificación se puede obtener una solución software de manera sistemática. Como validación de la propuesta, ésta se ha aplicado en la práctica con usuarios finales. Pese a que el proceso de desarrollo no ofrece una automatización completa, las guías ofrecidas y la formalización de los conceptos implicados ha demostrado ser útil a la hora de elevar el nivel de abstracción en el desarrollo, evitando el esfuerzo de enfrentarse a detalles tecnológicos. / Giner Blasco, P. (2010). Automating the development of Physical Mobile Workflows. A Model Driven Engineering approach [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8272

Actualmente existe una creciente demanda de sistemas flexibles, adaptables y con gran escalabilidad para apoyar las interacciones de personas e instituciones distribuidas en entornos heterogéneos. Esto se debe principalmente al incremento en la necesidad de trabajo colaborativo y la descentralización de los procesos en muchos dominios de aplicación. Por lo general, estas aplicaciones de software deben seguir legislaciones y normativas específicas, es decir, las entidades que participan en el sistema tienen derechos, deberes y restricciones específicas. Al igual que en otros trabajos del área, en esta tesis se utiliza el término sistemas normativos abiertos para referirse a los sistemas de este tipo. El desarrollo de sistemas normativos abiertos puede producir importantes beneficios para las compañías que los usen, ya que permiten la comunicación de instituciones, entidades heterogéneas y diferentes dispositivos con el fin de lograr tanto los objetivos globales del sistema como los individuales de cada institución y entidad. Sin embargo, también hay algunas cuestiones importantes que potencialmente pueden complicar el análisis, diseño e implementación de estos sistemas. La mayoría de estos problemas están relacionados con la interoperabilidad de sus procesos, la privacidad, la combinación de los objetivos individuales y la combinación de las restricciones y la legislación de cada una de las entidades del sistema. Por lo tanto, es necesario el uso de métodos de ingeniería del software y herramientas de desarrollo para hacer frente a estos problemas y guiar a los desarrolladores durante el proceso de desarrollo. La tecnología basada en sistemas multiagente (SMA) es considerada una buena candidata para el desarrollo de sistemas normativos abiertos. Durante los últimos años, el uso de las tecnologías SMA se ha incrementado no sólo en el ámbito académico, sino también en el desarrollo e implementación de aplicaciones industriales. Los SMA se han establecido como un paradigma de la ingeniería de software para la creación de sistemas adaptativos complejos, en entornos distribuidos y heterogéneos. Esta tesis se centra en el análisis y diseño de sistemas normativos abiertos utilizando la tecnología SMA. Algunas metodologías SMA se dedican al desarrollo de sistemas de este tipo. Sin embargo, después de analizar en qué medida las metodologías SMA actuales soportan el análisis y el diseño de estos sistemas, podemos concluir que todavía hay importantes problemas a resolver en el área. Algunos de estos problemas son la integración del contexto normativo del sistema durante el proceso de desarrollo, la falta de directrices para identificar y formalizar este contexto normativo, la falta de técnicas de validación y verificación que garanticen la coherencia del diseño final respecto a los requisitos del sistema, la coherencia entre los objetivos individuales, y la coherencia de las restricciones de cada entidad respecto al contexto normativo del sistema global. La principal aportación de esta tesis es una nueva metodología SMA llamada ROMAS (Sistemas Multiagente Regulados y Abiertos), que se centra en el análisis y diseño de procesos para el desarrollo de sistemas multiagente organizacionales, donde los agentes interactúan por medio de servicios estándares, y donde las relaciones sociales y contractuales se formalizan mediante normas y contratos. La metodología ROMAS define un proceso de desarrollo orientado a agentes y proporciona guías específicas para identificar y formalizar el marco normativo del sistema, así como las comunicaciones y los intercambios de servicios y recursos. ROMAS especifica tanto el comportamiento global del sistema como las características individuales de cada entidad. En la metodología ROMAS, agentes, roles y organizaciones se definen a través de una estructura social formal basada en un arquitectura orientada a servicios. Aquí, las organizaciones representan un conjunto de personas e instituciones que tienen que coor / Garcia Marques, ME. (2013). Engineering Regulated Open Multiagent Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/28588

The instruction-set based general purpose processors are not energy-efficient for event-driven applications. The E-textiles group at Virginia Tech proposed a novel data-flow processor architecture design to bridge the gap between event-driven applications and the target architecture. The architecture, although promising in terms of performance and energy-efficiency, was explored for limited number of applications. This thesis presents a model-driven approach for the design of an application framework, facilitating rapid development of software applications to test the architecture performance. The application framework is integrated with the prior automation framework bringing software applications at the right level of abstraction. The processor architecture design is made flexible and scalable, making it suitable for a wide range of applications. Additionally, an embedded flash memory based architecture design for reduction in the static power consumption is proposed. This thesis estimates significant reduction in overall power consumption with the incorporation of flash memory. / Master of Science

We describe CoSMo, a Cognitively Inspired Service and Model Architecture for situational awareness and monitoring of vehicular traffic in urban transportation systems using a network of wireless sensors. The system architecture combines (i) a cognitively inspired internal representation for analyzing and answering queries concerning the observed system and (ii) a service oriented architecture that facilitates interaction among individual modules, of the internal representation, the observed system and the user. The cognitively inspired model architecture allows effective deductive as well as inductive reasoning by combining simulation based dynamic models for planning with traditional relational databases for knowledge and data representation. On the other hand the service oriented design of interaction allows one to build flexible, extensible and scalable systems that can be deployed in practical settings. To illustrate our concepts and the novel features of our architecture, we have recently completed a prototype implementation of CoSMo. The prototype illustrates advantages of our approach over other traditional approaches for designing scalable software for situational awareness in large complex systems. The basic architecture and its prototype implementation are generic and can be applied for monitoring other complex systems. This thesis describes the design of cognitively-inspired model architecture and its corresponding prototype. Two important contributions include the following: • The cognitively-inspired architecture: In contrast to earlier work in model driven architecture, CoSMo contains a number of cognitively inspired features, including perception, memory and learning. Apart from illustrating interesting trade-offs between computational cost (e.g. access time, memory), and correctness available to a user, it also allows users specified deductive and inductive queries. • Distributed Data Integration and Fusion: In keeping with the cognitively-inspired model-driven approach, the system allows for an efficient data fusion from heterogeneous sensors, simulation based dynamic models and databases that are continually updated with real world and simulated data. It is capable of supporting a rich class of queries. / Master of Science

La complexité croissante des systèmes d'information modernes a motivé l'apparition de nouveaux paradigmes (objets, composants, services, etc), permettant de mieux appréhender et maîtriser la masse critique de leurs fonctionnalités. Ces systèmes sont construits de façon modulaire et adaptable afin de minimiser les temps d'arrêts dus aux évolutions ou à la maintenance de ceux-ci. Afin de garantir des propriétés non fonctionnelles (par ex. maintien du temps de réponse malgré un nombre croissant de requêtes), ces systèmes sont également amenés à être distribués sur différentes ressources de calcul (grilles). Outre l'apport en puissance de calcul, la distribution peut également intervenir pour distribuer une tâche sur des nœuds aux propriétés spécifiques. C'est le cas dans le cas des terminaux mobiles proches des utilisateurs ou encore des objets et capteurs connectés proches physiquement du contexte de mesure. L'adaptation d'un système et de ses ressources nécessite cependant une connaissance de son état courant afin d'adapter son architecture et sa topologie aux nouveaux besoins. Un nouvel état doit ensuite être propagé à l'ensemble des nœuds de calcul. Le maintien de la cohérence et le partage de cet état est rendu particulièrement difficile à cause des connexions sporadiques inhérentes à la distribution, pouvant amener des sous-systèmes à diverger. En réponse à ces défi scientifiques, cette thèse propose une abstraction de conception et de déploiement pour systèmes distribués dynamiquement adaptables, grâce au principe du Model@Runtime. Cette approche propose la construction d'une couche de réflexion distribuée qui permet la manipulation abstraite de systèmes répartis sur des nœuds hétérogènes. En outre, cette contribution introduit dans la modélisation des systèmes adaptables la notion de cohérence variable, permettant ainsi de capturer la divergence des nœuds de calcul dans leur propre conception. Cette couche de réflexion, désormais cohérente "à terme", permet d'envisager la construction de systèmes adaptatifs hétérogènes, regroupant des nœuds mobiles et embarqués dont la connectivité peut être intermittente. Cette contribution a été concrétisée par un projet nommé ''Kevoree'' dont la validation démontre l'applicabilité de l'approche proposée pour des cas d'usages aussi hétérogènes qu'un réseau de capteurs ou une flotte de terminaux mobiles. / The growing complexity of modern IT systems has motivated the development of new paradigms (objects, components, services,...) to better cope with the critical size of their functionalities. Such systems are then built as a modular and dynamically adaptable compositions, allowing them to minimise their down-times while performing evolutions or fixes. In order to ensure non-functional properties (i.e. request latency) such systems are distributed across different computation nodes. Besides the added value in term of computational power (cloud), this distribution can also target nodes with dedicated properties such as mobile nodes and sensors (internet of things), physically close to users for interactions. Adapting a system requires knowledge about its current state in order to adapt its architecture to its evolving needs. A new state must be then disseminated to other nodes to synchronise them. Maintaining its consistency and sharing this state is a difficult task especially in case of sporadic connexions which lead to divergent state between sub-systems. To tackle these scientific problems, this thesis proposes an abstraction to design and deploy distributed adaptive systems following the Model@Runtime paradigm. From this abstraction, the proposed approach allows defining a distributed reflexive layer to manipulate heterogeneous distributed nodes. In particular, this contribution introduces variable consistencies in model definition and divergence in system conception. This reflexive layer, eventually consistent allows the construction of distributed adapted systems even on mobile nodes with intermittent connectivity. This work has been realized in an open source project named Kevoree, and validated on various distributed systems ranging from sensor networks to “cloud” computing.

Modeliais grįsta sistemų architektūra (MDA) yra „Object Management Group“ (OMG) konsorciumo iniciatyva apibrėžti naują požiūrį į programų sistemų kūrimą remiantis modeliais ir automatizuota jų transformacija į programinį kodą. Siekdama standartizuoti šį požiūrį, OMG patvirtino visą eilę standartų, bet esminiai MDA principai ir praktikos glūdi modeliais grįstame sistemų kūrimo stiliuje, kuris yra fundamentalus programų sistemų inžinerijoje. MDA idėjos, pradžioje sukėlusios didelį entuziazmą IT bendruomenėje, ilgainiui peraugo į skepticizmą ir kai kurie autoriai atvirai pradėjo abejoti modeliais grįsto sistemų kūrimo perspektyva. Šiame darbe analizuojamos praktinio MDA taikymo programų sistemų kūrimo procese aspektai ir galimybės, analizuojami galimi sprendimai ir kliūtys, dėl kurių MDA požiūris gali būti sunkiai pritaikomas. Įvairių autorių įvardijami praktiniai MDA taikymo programų sistemų kūrimo procese sunkumai, didelės tam reikalingos investicijos, pastangos ir resursai, tinkamų instrumentų trūkumas, didelė standartų įvairovė ir sudėtingos technologijos iš dalies lėmė išaugusį skepticizmą MDA paradigmai. MDA apibrėžia naujus sistemų kūrimo principus ir standartais apibrėžia technologijas, kurios pagrindžia šiuos principus. Tai neišvengiamai įtakoja patį programų sistemų kūrimo procesą, kuris turi pasipildyti naujomis veiklomis, praktikomis ir technologijomis, kaip kurti sistemas taikant MDA požiūrį. Šiame kontekste būtinas tam tikras pragmatinis požiūris į MDA ir su juo... [toliau žr. visą tekstą] / Model Driven Architecture (MDA) is an approach to using models in software development, which states that models and model-based transformations are a key part of effective automated software development. The Object Management Group (OMG) has defined standards for representing MDA models, but the principles and practice of MDA are rooted in model-based styles of development that have been fundamental to software engineering from its earliest days. Unfortunately, early enthusiasm for Model Driven Architecture (MDA) has dissipated to the point that many people are openly skeptical of the value of any model-driven approach. This paper examines the practical realities of MDA, difficulties and challenges in adopting an MDA approach to software engineering process. While MDA requires additional efforts and high investment to be adopted in software engineering process, it doesn’t provide any means or guidelines for this. This paper argues that to be successful, a pragmatic MDA approach must be executed in context of a sound Enterprise Architecture providing an integrated business architecture and governance structure that enables an organization to respond to business requirements quickly and appropriately.