Cette thèse traite de systèmes embarqués contrôlés par un ensemble de processus périodiques non synchronisés. Chaque processus est activé quasi-périodiquement, c'est-à-dire périodiquement avec une gigue bornée. Les délais de communication sont également bornés. De tels systèmes réactifs, appelés 'quasi-périodiques', apparaissent dès que l'on branche ensemble deux processus périodiques. Dans la littérature, ils sont parfois qualifiés de systèmes distribués temps-réels synchrones. Nous nous intéressons aux techniques de conception et d'analyse de ces systèmes qui n'imposent pas de synchronisation globale. Les langages synchrones ont été introduits pour faciliter la conception des systèmes réactifs. Ils offrent un cadre privilégié pour programmer, analyser, et vérifier des systèmes quasi-périodiques. En s'appuyant sur une approche synchrone, les contributions de cette thèse s'organisent selon trois thématiques: vérification,implémentation, et simulation des systèmes quasi périodiques.Vérification: 'L'abstraction quasi-synchrone' est une abstraction discrète proposée par Paul Caspi pour vérifier des propriétés de sûreté des systèmes quasi-périodiques. Nous démontrons que cette abstraction est en général incorrecte et nous donnons des conditions nécessaires et suffisantes sur le graphe de communication et les caractéristiques temps-réel de l'architecture pour assurer sa correction. Ces résultats sont ensuite généralisés aux systèmes multi-périodiques.Implémentation: Les 'LTTAs' sont des protocoles conçus pour assurer l'exécution correcte d'une application sur un système quasi-périodique. Nous proposons d'étudier les LTTA dans un cadre synchrone unifié qui englobe l'application et les contrôleurs introduits par les protocoles. Cette approche nous permet de simplifier les protocoles existants, de proposer des versions optimisées, et de donner de nouvelles preuves de correction. Nous présentons également dans le même cadre un protocole fondé sur une synchronisation d'horloge pour comparer les performances des deux approches.Simulation: Un système quasi-périodique est un exemple de modèle faisant intervenir des caractéristiques temps-réels et des tolérances. Pour ce type de modèle non déterministe, nous proposons une 'simulation symbolique', inspirée des techniques de vérification des automates temporisés. Nous montrons comment compiler un modèle mêlant des composantes temps-réel non déterministes et des contrôleurs discrets en un programme discret qui manipule des ensembles de valeurs. Chaque trace du programme résultant capture un ensemble d'exécutions possibles du programme source. / In this thesis we study embedded controllers implemented as sets of unsynchronized periodic processes. Each process activates quasi-periodically, that is, periodically with bounded jitter, and communicates with bounded transmission delays. Such reactive systems,termed 'quasi-periodic', exist as soon as two periodic processes areconnected together. In the distributed systems literature they arealso known as synchronous real-time models. We focus on techniquesfor the design and analysis of such systems without imposing a globa lclock synchronization. Synchronous languages were introduced as domain specific languages for the design of reactive systems. They offer an ideal framework to program, analyze, and verify quasi-periodic systems. Based on a synchronous approach, this thesis makes contributions to the treatment of quasi-periodic systems along three themes: verification,implementation, and simulation.Verification: The 'quasi-synchronous abstraction' is a discrete abstraction proposed by Paul Caspi for model checking safety properties of quasi-periodic systems. We show that this abstractionis not sound in general and give necessary and sufficient conditionson both the static communication graph of the application and the real-time characteristics of the architecture to recover soundness. We then generalize these results to multirate systems.Implementation: 'Loosely time-triggered architectures' are protocols designed to ensure the correct execution of an application running on a quasi-periodic system. We propose a unified framework that encompasses both the application and the protocol controllers. This framework allows us to simplify existing protocols, propose optimized versions, and give new correctness proofs. We instantiate our framework with a protocol based on clock synchronization to compare the performance of the two approaches.Simulation: Quasi-periodic systems are but one example of timed systems involving real-time characteristics and tolerances. For such nondeterministic models, we propose a 'symbolic simulation' scheme inspired by model checking techniques for timed automata. We show how to compile a model mixing nondeterministic continuous-time and discrete-time dynamics into a discrete program manipulating sets of possible values. Each trace of the resulting program captures a set of possible executions of the source program.

The purpose of this study is to explore and interpret the different meanings and consequences of diversity and its associated practices for the police organization in Sweden. By highlighting possible discourses on the concept of diversity within the police organization and how the police organization presents the concept of diversity, based on that, contribute to an increased understanding of the police organization’s diversity work. Our study is based on a qualitative method, discourse analysis, which has helped us collect the empirical material. The purpose with discourse analysis is to interpret what is written, therefore this study is based on our own interpretations of the empirical material. The empirical material that consists of the police policy documents has in turn been analyzed based on Carol Bacchi’s “What’s the problem represented to be-approach” (WPR-approach) and the neo-institutional theory where concepts such as isomorphism and loosely coupled occur. When studying the police organization, the concept of diversity is seen to be common. The police highlights the importance of having diversity within their organization, which can be seen to have emerged over time. The result of this study indicates that the police organization works actively to make equal treatment a natural part of the organization today. This includes wanting to reflect society and they believe that diversity entails different skills which they want to utilize within the organization. The study also describes three different problem representations which we have identified in the empirical material. These problem representations have in turn helped us to highlight different discourses about the concept of diversity, which has contributed to an increased understanding of the police organization’s diversity work.

This thesis presents an investigation of the possibility of using the fixed-point arithmetic in the inertial navigation systems, which use the local level navigation frame mechanization equations. Two square root filtering methods, the Potter's square root Kalman filter and UD factorized Kalman filter, are compared with respect to the conventional Kalman filter and its Joseph's stabilized form. The effect of rounding errors to the Kalman filter optimality and the covariance matrix or its factors conditioning is evaluated for a various lengths of the fractional part of the fixed-point computational word. Main contribution of this research lies in an evaluation of the minimal fixed-point arithmetic word length for the Phi-angle error model with noise statistics which correspond to the tactical grade inertial measurements units.

Dagens organisationer kontrolleras allt mer, där granskning och mätning tenderar att genomföras av all dokumentation som behandlats i offentlig verksamhet. I förlängningen är utredningar i offentlig verksamhet idag en vanligt förekommande arbetsuppgift för HR specialister och syftet med studien är att undersöka betydelsen av utredningar i kommuner. För att kunna utreda olika typer av ärenden som kan innefatta både arbetsrättsliga och arbetsmiljömässiga problem krävs vissa kunskaper. Mer specifikt innebär det att undersöka betydelsen av och kompetensförutsättningar för utredningar utförda i tre olika kommuner ur ett HR-perspektiv. Under tidigare forskning behandlas frågan om kontroll av medarbetares arbete, ansvarsutkrävning av professioner, värdeskapande organisationer, organisatoriskrättvisa samt, betydelsen av kunskap och New Public Management (NPM), en styrform som vunnit allt mer mark i offentlig verksamhet. Teorier som använts som grund för att analyserainsamlad empiri kring utredningar och dess betydelse är legitimitet, HR-transformation, ny institutionell teori, isomorfism och isärkoppling. För att kunna utreda olika typer av ärenden som kan innefatta både arbetsrättsliga och arbetsmiljömässiga problem krävs vissa kunskaper. Studiens resultat visar att HR-specialister anser att utredningar är betydelsefulla i offentlig verksamhet, både för de individer det berör men även för arbetsmiljön som helhet. De understryker vikten av kunskap i utredningsmetodik för att kunna genomföra utredningar av god kvalitet. Resultatet ger en indikation på att HR-specialister i offentlig verksamhet ser utredningar som värdefulla handlingar som kan bidra till en bättre arbetsmiljö. Dock saknas i organisationerna strukturer för återkoppling och uppföljning av genomförda utredningar, 3vilket innebär att det saknas en vetskap bland respondenterna om vad som sker efter en utfördutredning.

This thesis explores the integration of IoT protocols to enhance supply chain efficiency and sustainability by developing a flexible automated system. The research covers the integration of a palletization optimizer with a flexible robotic platform, a project conducted in collaboration with OpiFlex and Linköping University. Flexibility and sustainability in production, particularly in the food and beverage industry, are critical yet challenging to achieve. This research addresses these challenges by proposing a system that aligns the output with customer needs by combining these technologies. The research employs a combination of case study and exploratory methodologies. The development approach synthesizes elements from Set-Based Design, Point-Based Design, and Agile development frameworks. The primary research questions focus on identifying the best system architecture for integrating the palletization optimizer with a lower-level automation platform and outlining the steps needed to transform this integration into a commercially viable product. The system includes the optimizer, capable of processing customer orders and configuring products on mixed output pallets, integrated with a flexible robotic system provided by OpiFlex. The work involved evaluating communication protocols, MQTT, OPC UA, and TCP/IP, and designing robust interactions and interfaces between the subsystems. The results demonstrate the system's architecture and interaction protocols.  The thesis concludes with a discussion of the results in comparison to the application scenario and the standards consulted. The conclusion is that the chosen interface practices should remain largely intact but be re-developed using an OPC UA-based architecture. The main reasons for this are its support for both pub/sub and client-server models, increased security, and greater support for enterprise application integration. However, depending on the specific application, the downsides of OPC UA may outweigh its benefits.