Doctor of Philosophy / Department of Computing and Information Sciences / Gurdip Singh / Cyber-Physical Systems (CPSs) represent the next-generation systems characterized by strong coupling of computing, sensing, communication, and control technologies. They have the potential to transform our world with more intelligent and efficient systems, such as Smart Home, Intelligent Transportation System, Energy-Aware Building, Smart Power Grid, and Surgical Robot. A CPS is composed of a computational and a physical subsystem. The computational subsystem monitors, coordinates and controls operations of the physical subsystem to create desired physical effects, while the physical subsystem performs physical operations and gives feedback to the computational subsystem. This dissertation contributes to the research of CPSs by proposing a new transaction model for Environmental Resource Dependent Cyber-Physical Systems (ERDCPSs). The physical operations of such type of CPSs rely on environmental resources, and they are commonly seen in areas such as transportation and manufacturing. For example, an autonomous car views road segments as resources to make movements and a warehouse robot views storage spaces as resources to fetch and place goods. The operating environment of such CPSs, CPS Network, contains multiple CPS entities that share common environmental resources and interact with each other through usages of these resources. We model physical operations of an ERDCPS as a set of transactions of different types that achieve different goals, and each transaction consists of a sequence of actions. A transaction or an action may require environmental resources for its operations, and the usage of an environmental resource is precise in both time and space. Moreover, a successful execution of a transaction or an action requires exclusive access to certain resources. Transactions from different CPS entities of a CPS Network constitute a schedule. Since environmental resources are shared, transactions in the schedule may have conflicts in using these resources. A schedule must remain consistent to avoid unexpected consequences caused by resource usage conflicts between transactions. A two-phase commit algorithm is proposed to process transactions. In the pre-commit phase, a transaction is scheduled by reserving usage times of required resources, and potential conflicts are detected and resolved using different strategies, such as Win-Lose, Win-Win, and Transaction Preemption. Two general algorithms are presented to process transactions in the pre-commit phase for both centralized and distributed resource management environments. In the commit phase, a transaction is executed using reserved resources. An exception occurs when the real-time resource usage is different from what has been predicted. By doing internal and external check before a scheduled transaction is executed, exceptions can be detected and handled properly. A simulation platform (CPSNET) is developed to simulate the transaction model. The simulation platform simulates a CPS Network, where different CPS entities coordinate resource usages of their transactions through a Communication Network. Depending on the resource management environment, a Resource Server may exist in the CPS Network to manage resource usages of all CPS entities. The simulation platform is highly configurable and configuration of the simulation environment, CPS entities and two-phase commit algorithm are supported. Moreover, various statistical information and operation logs are provided to monitor and evaluate the platform itself and the transaction model. Seven groups of simulation experiments are carried out to verify the simulation platform and the transaction model. Simulation results show that the platform is capable of simulating a large load of CPS entities and transactions, and entities and components perform their functions correctly with respect to the processing of transactions. The two-phase commit algorithm is evaluated, and the results show that, compared with traditional cases where no conflict resolving is applied or a conflicting transaction is directly aborted, the proposed conflict resolving strategies improve the schedule productivity by allowing more transactions to be executed and the scheduling throughput by maintaining a higher concurrency level.

Comme de nombreux grands projets industriels, Énergie Saguenay a généré sa part de controverse. En effet, de 2014 à aujourd’hui, différents acteurs ont publiquement partagé leurs conceptions du projet. Ils l’ont défini à leur manière, s’opposant et se rejoignant parfois sur certains points. Mon objectif de recherche général est donc de décrire le processus de dispute propre à Énergie Saguenay dans ses caractéristiques rhétoriques et ses effets propres. Pour rendre compte de cet objectif, je mobilise trois littératures scientifiques. Premièrement, la littérature sur les controverses sociotechniques m’a permis de concevoir comment, d’un côté, des réseaux d’acteurs se forment et évoluent par et tout au long d’une controverse et de l’autre, comment les controverses agissent comme un lieu d’apprentissage et d’expression. Deuxièmement, je me suis inspirée de la problématisation, première étape du modèle de la traduction (Callon, 1986), pour identifier les points passages obligés (PPO) de la controverse Énergie Saguenay, soit ses principaux enjeux auxquels les acteurs doivent consentir pour sceller des alliances. Finalement, j’ai fait appel à la théorie des arguments de définition mise de l’avant par Schiappa (2003) et Zarefsky (1997) pour définir dans quel genre de controverse s’inscrit Énergie Saguenay et comment les définitions particulières d’un phénomène, en particulier le gaz en tant qu’énergie de transition, participent à la formulation de PPO. Dans l’ensemble, mon travail de recherche contribue à rendre compte des manières dont les pratiques de définition nous aident à comprendre comment, sur le plan rhétorique, se créent des points de passage obligés dans une controverse. Plus spécifiquement, par l’analyse des mémoires déposés au BAPE par les acteurs qui composent les groupes sociaux qui ont participé à la controverse, mon étude met de l’avant les différentes pratiques de définition et conceptions du gaz naturel qui existent en ce moment au Québec comme autant de PPO permettant aux acteurs de s’allier ou de s’opposer les uns aux autres, tout au long de la controverse. / Like many large industrial projects, Énergie Saguenay has generated its share of controversy. Indeed, from 2014 to today, various groups of social actors have publicly shared their conceptions of the project. They defined it in their own way, agreeing on some points and disagreeing on others. My general research objective is therefore to describe the dispute process specific to Énergie Saguenay in its rhetorical characteristics and its own effects. To account for this objective, I will mobilize three scientific literatures. First, the literature on socio-technical controversies has allowed me to conceive how on the one hand, networks of social actors are formed and evolve during a controversy and on the other, how controversies create a space for learning and expression. Second, I was inspired by problematization, the first stage of the translation model (Callon, 1986), to identify the obligatory points of passage (OPP) of the Énergie Saguenay controversy, i.e., these main issues to which the various groups of social actors must agree to seal alliances. Finally, I appealed to the theory of definition arguments put forward by Schiappa (2003) and Zarefsky (1997) to define what category of controversy Énergie Saguenay fits into and how the specific definitions of a phenomenon (in particular gas as a transition energy) participate in the formulation of OPP. Overall, my research helps capture the ways in which defining practices help us understand how, at the rhetorical level, OPPs are created in controversy. More specifically, by analyzing the briefs submitted to the BAPE by the actors who make up the social groups who had participated in the controversy, my study puts forward the different definition practices that contributed to the conceptions of natural gas that currently exist in Québec, as so many OPPs allow the actors to align or oppose each other throughout the controversy.