Supporting multidisciplinary vehicle modeling : towards an ontology-based knowledge sharing in collaborative model based systems engineering environment

Simulation models are widely used by industries as an aid for decision making to explore and optimize a broad range of complex industrial systems’ architectures. The increased complexity of industrial systems (cars, airplanes, etc.), ecological and economic concerns implies a need for exploring and analysing innovative system architectures efficiently and effectively by using simulation models. However, simulations designers currently suffer from limitations which make simulation models difficult to design and develop in a collaborative, multidisciplinary design environment. The multidisciplinary nature of simulation models requires a specific understanding of each phenomenon to simulate and a thorough description of the system architecture, its components and connections between components. To accomplish these objectives, the Model-Based Systems Engineering (MBSE) and Information Systems’ (IS) methodologies were used to support the simulation designer’s analysing capabilities in terms of methods, processes and design tool solutions. The objective of this thesis is twofold. The first concerns the development of a methodology and tools to build accurate simulation models. The second focuses on the introduction of an innovative approach to design, product and integrate the simulation models in a “plug and play" manner by ensuring the expected model fidelity. However, today, one of the major challenges in full-vehicle simulation model creation is to get domain level simulation models from different domain experts while detecting any potential inconsistency problem before the IVVQ (Integration, Verification, Validation, and Qualification) phase. In the current simulation model development process, most of the defects such as interface mismatch and interoperability problems are discovered late, during the IVVQ phase. This may create multiple wastes, including rework and, may-be the most harmful, incorrect simulation models, which are subsequently used as basis for design decisions. In order to address this problem, this work aims to reduce late inconsistency detection by ensuring early stage collaborations between the different suppliers and OEM. Thus, this work integrates first a Detailed Model Design Phase to the current model development process and, second, the roles have been re-organized and delegated between design actors. Finally an alternative architecture design tool is supported by an ontology-based DSL (Domain Specific Language) called Model Identity Card (MIC). The design tools and mentioned activities perspectives (e.g. decisions, views and viewpoints) are structured by inspiration from Enterprise Architecture Frameworks. To demonstrate the applicability of our proposed solution, engine-after treatment, hybrid parallel propulsion and electric transmission models are tested across automotive and aeronautic industries.Les systèmes industriels (automobile, aérospatial, etc.) sont de plus en plus complexes à cause des contraintes économiques et écologiques. Cette complexité croissante impose des nouvelles contraintes au niveau du développement. La question de la maitrise de la capacité d’analyse de leurs architectures est alors posée. Pour résoudre cette question, les outils de modélisation et de simulation sont devenus une pratique courante dans les milieux industriels afin de comparer les multiples architectures candidates. Ces outils de simulations sont devenus incontournables pour conforter les décisions. Pourtant, la mise en œuvre des modèles physiques est de plus en plus complexe et nécessite une compréhension spécifique de chaque phénomène simulé ainsi qu’une description approfondie de l’architecture du système, de ses composants et des liaisons entre composants. L’objectif de cette thèse est double. Le premier concerne le développement d’une méthodologie et des outils nécessaires pour construire avec précision les modèles de simulation des architectures de systèmes qu’on désire étudier. Le deuxième s’intéresse à l’introduction d’une approche innovante pour la conception, la production et l’intégration des modèles de simulations en mode « plug and play » afin de garantir la conformité des résultats aux attentes, notamment aux niveaux de la qualité et de la maturité. Pour accomplir ces objectifs, des méthodologies et des processus d’ingénierie des systèmes basés sur les modèles (MBSE) ainsi que les systèmes d’information ont été utilisés. Ce travail de thèse propose pour la première fois un processus détaillé et un outil pour la conception des modèles de simulation. Un référentiel commun nommé « Modèle de carte d'identité (MIC) » a été développé pour standardiser et renforcer les interfaces entre les métiers et les fournisseurs sur les plans organisationnels et techniques. MIC garantit l’évolution et la gestion de la cohérence de l’ensemble des règles et les spécifications des connaissances des domaines métiers dont la sémantique est multiple. MIC renforce également la cohérence du modèle et réduit les anomalies qui peuvent interférer pendant la phase dite IVVQ pour Intégration, Vérification, Validation, Qualification. Finalement, afin de structurer les processus de conception des modèles de simulation, le travail s’est inspiré des cadres de l’Architecture d’Entreprise en reflétant les exigences d’intégration et de standardisation du modèle opératoire de l’entreprise. Pour valider les concepts introduits dans le cadre de cette thèse, des études de cas tirés des domaines automobile et aérospatiale ont été réalisées. L'objectif de cette validation est d'observer l'amélioration significative du processus actuel en termes d'efficacité, de réduction de l'ambiguïté et des malentendus dans la modélisation et la simulation du système à concevoir

Changing the Paradigm: Using an Integrative Approach to Improve Understanding of Tuberculosis Control in Michigan.

Background. In the U.S., tuberculosis (TB) continues to disproportionately affect the poor, racial/ethnic minorities, and urban dwellers, yet traditional methods of TB control focus primarily on biomedical predictors for treatment and less on social factors that could direct prevention. Although characteristics of the social and physical environment increase vulnerability to TB, declining concern over those with disease and diminished resources have stunted understanding of risk and reduced the ability to respond. Methods. Using TB case surveillance data combined with genotypic testing of samples from the Michigan Department of Health and Human Service and a novel socio-demographic survey, this dissertation takes an integrative approach to understanding the patterns of TB incidence and transmission. Research has involved: 1. Analyzing risk factors for TB incidence in Michigan; 2. Evaluating which risk factors both at the individual- and neighborhood levels were associated with pathogen genotypic and temporal clustering; and 3. Analyzing social characteristics of TB cases diagnosed in Metro Detroit to better understand how social vulnerability and behavioral contacts augment risk. Results. From 2004 through 2012, the incidence of TB throughout Michigan declined by an average of 8% per year. However, significant disparities in the average incidence rate were observed by race and nativity. Overall, 22% of the foreign-born cases of TB were estimated to be resulting from recent transmission of TB compared to 52% of the U.S.-born cases. For the U.S.-born, recent transmission was predicted more by individual-level and neighborhood-level socio-demographic factors than by clinical risk factors. Preliminary results from the socio-demographic survey suggest that while individuals with TB in Metro Detroit may be employed and have access to stable housing, they still experience significant financial strain. Conclusions: The results of this dissertation highlight some of the ways in which TB incidence is socially patterned. Interventions aimed at reducing the incidence of TB in the foreign-born population should focus on reducing reactivation of latent TB infections. However, reducing the incidence of TB among the U.S.-born will require strategies that can reduce transmission of TB among socially disadvantaged groups, both at the individual- and neighborhood-level.PhDEpidemiological ScienceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/120803/1/gnoppert_1.pd

A METHODOLOGY FOR THE MODULARIZATION OF OPERATIONAL SCENARIOS FOR MODELLING AND SIMULATION

As military operating environments and potential global threats rapidly evolve, military planning processes required to maintain international security and national defense increase in complexity and involve unavoidable uncertainties. The challenges in the field are diverse, including dealing with reemergence of long-term, strategic competition over destabilizing effects of rogue regimes, and the asymmetric non-state actors’ threats such as terrorism and international crime. The military forces are expected to handle increased multi-role, multi-mission demands because of the interconnected character of these threats. The objective of this thesis is to discuss enhancing system-of-systems analysis capabilities by considering diverse operational requirements and operational ways in a parameterized fashion within Capabilities Based Assessments process. These assessments require an open-ended exploratory approach of means and ways, situated in the early stages of planning and acquisition processes. In order to enhance the reflection of increased demands in the process, the integration of multi-scenario capabilities into a process with low-fidelity modelling and simulation is of particular interest. This allows the consideration of a high quantity of feasible alternatives in a timely manner, spanning across a diverse set of dimensions and its parameters. A methodology has been devised as an enhanced Capabilities Based Assessment approach to provide for a formalized process for the consideration and infusion of operational scenarios, and properly constrain the design space prior to computational analysis. In this context, operational scenarios are a representative set of statements and conditions that address a defined problem and include testable metrics to analyze performance and effectiveness. The scenario formalization uses an adjusted elementary definition approach to decompose, define, and recompose operational scenarios to create standardized architectures, allowing their rapid infusion into environments, and to enable the consideration of diverse operational requirements in a conjoint approach overall. Pursuant to this process, discrete event simulations as low-fidelity approach are employed to reflect the elementary structure of the scenarios. In addition, the exploration of the design and options space is formalized, including the collection of alternative approaches within different materiel and non-materiel dimensions and subsequent analysis of their relationship prior to the creation of combinatorial test cases. In the progress of this thesis, the devised methodology as a whole and the two developed augmentations to the Capabilities Based Assessment are tested and validated in a series of experiments. As an overall case study, the decision-making process surrounding the deployment of vertical airlift assets of varying type and quantity for Humanitarian Aid and Disaster Relief operations is utilized. A demonstration experiment is provided exercising the entire methodology to test specifically for its suitability to handle a variety of different scenarios through process, as well as a comprehensive set of materiel and non-materiel parameters. Based on a mission statement and performance targets, the status quo could be evaluated and alternative options for the required performance improvements could be presented. The methodology created in this thesis enables the Capabilities Based Assessment and general defense acquisition considerations to be initially approached in a more open and less constrained manner. This capability is provided through the use of low-fidelity modelling and simulation that enables the evaluation of a large amount of alternatives. In advances to the state of the art, the methodology presented removes subject-matter expert and operator driven constraints, allowing the discovery of solutions that would not be considered in a traditional process. It will support the work of not only defense acquisition analysts and decision-makers, but also provide benefits to policy planners through its ability to instantly revise and analyze cases in a rapid fashion.Ph.D

Ecología y sociedad: gestión del conejo de monte en la Península Ibérica

The European rabbit (Oryctolagus cuniculus) is considered a key species of Mediterranean ecosystems, to which it is native. In 2019, the IUCN reassessed the status of the species to that of threatened in the Iberian Peninsula due to the decline that had experienced its populations during the last decades. Paradoxically, the species has increased its presence in some Iberian areas, being considered a "plague" for damaging crops and infrastructures. Thus, there is debate among managers, farmers and hunters regarding the objectives of rabbit management (i.e., for population control or increase). A plausible hypothesis to explain this paradoxical situation is the existence of two independent evolutionary units recognized by the IUCN as two subspecies (O.c.cuniculus and O.c.algirus). They present well-defined geographical distributions as well as genetic and morphological differences that even led Darwin to consider them different species. In fact, increasing research indicates that both genetic groups are in an advanced process of speciation, suggesting the need to establish different management measures for each one. The general objective of this doctoral thesis is to develop scientific knowledge to understand the situation of the rabbit and its subspecies in the Peninsula and provide optimal management recommendations for this species in its various contexts. To do this, it pays simultaneous attention to two aspects that have barely been explored in the scientific literature to date: the rabbit subspecies and the study of the social dimension related to its management. In general, an interdisciplinary approach is used for this purpose, combining both ecological and sociological studies. The results highlight the existence of notable differences between the rabbit subspecies, which can support an independent management framework and may help to guarantee the conservation of the O.c.algirus. In addition, the results of this doctoral thesis also suggest an apparent disconnection between the social perception of rabbit problems and research-based knowledge, which emphasizes the need to involve all parties in charge of rabbit management in the construction and communication of knowledge. Such an approach can reduce existing conflict and polarization in the management of the species. Regardless of future decisions about where to draw the boundaries between rabbit subspecies, this study emphasizes the need to understand the social and ecological factors under which the species is managed. In addition, this research on subspecies and the social aspects associated with their management, as well as the practical recommendations offered, could be extended to any other species in similar circumstances.El conejo europeo (Oryctolagus cuniculus) es considerada una especie clave de los ecosistemas mediterráneos, de los que es autóctona. En 2019, la UICN reevaluó el estatus de la especie al de amenazada en la Península Ibérica como consecuencia del declive que han experimentado sus poblaciones en las últimas décadas. Paradójicamente, la especie ha aumentado su presencia en algunas zonas de cultivo ibéricas, siendo considerada una "plaga" por dañar cultivos e infraestructuras. Existe pues un debate cada vez mayor entre los gestores, agricultores y cazadores con respecto a los objetivos de gestion del conejo (es decir, para el control o aumento de la población). Una hipótesis plausible para explicar esta paradójica situación es la existencia de dos unidades evolutivas independientes reconocidas por la UICN como dos subespecies (O.c.cuniculus y O.c.algirus). Presentan distribuciones geográficas bien definidas así como diferencias genéticas y morfológicas que incluso llevaron a Darwin a considerarlas especies distintas. De hecho, cada vez más investigaciones señalan que ambos grupos genéticos se encuentran en un proceso avanzado de especiación, lo que sugiere la necesidad de establecer diferentes medidas de gestión para cada uno. El objetivo general de esta tesis doctoral es desarrollar conocimiento científico que ayude a comprender la situación del conejo y de sus subespecies en la Península con el fin de proporcionar recomendaciones de gestión óptimas para esta especie en sus diversos contextos. Para ello, presta atención simultánea a dos aspectos escasamente explorados en la literatura científica hasta la fecha: las subespecies des de conejo y el estudio de la dimensión social relativa a su gestión. En general, con este fin se emplea un enfoque interdisciplinar que combina estudios tanto ecológicos como sociológicos. Los resultados destacan la existencia de diferencias notables entre las subespecies de conejo, lo que puede apoyar la necesidad de un manejo independiente que garantice la conservación de O.c.algirus. Además, los resultados de esta tesis doctoral también sugieren una aparente desconexión entre la percepción social que se tiene sobre los problemas del conejo y el conocimiento basado en la investigación, lo que enfatiza la necesidad de involucrar a todas las partes encargadas de la gestión del conejo en la construcción y comunicación del conocimiento. Tal enfoque puede reducir el conflicto existente y la polarización en la gestión de la especie. Independientemente de las decisiones futuras sobre dónde trazar los límites entre las subespecies de conejo, este estudio enfatiza la necesidad de comprender los factores sociales y ecológicos en los que se gestiona la especie. En general, las investigaciones sobre las subespecies y los aspectos sociales asociados a su gestión, así como las recomendaciones prácticas que se ofrecen, podrían extenderse a cualquier otra especie en circunstancias similares

Context Dependency of Community Dynamics: Predator-Prey Interactions Under Ecological Disturbances

Numerous studies have focused on the drivers of diversity and stability of communities, especially under global change. However, multi-dimensionality of ecosystems due to biotic components (e.g predation, competition and adaptive dynamics) and abiotic factors (e.g. disturbances, resource dynamics and their distinct attributes) cause context-dependent outcomes and challenge the predictions. There are still controversies around complex community dynamics under varying regimes, however, finding mechanistical explanations will illuminate the fate of multispecies assemblages. Using model microbial communities, consisting of bacterial prey and protist predator, combined with simulation modelling and advanced statistics, this thesis investigated the impact of imposed disturbances (i.e. increased dilution rates that simulate density-independent mortality as press or pulse disturbances) (i) on transient recovery dynamics of a simple microbial food web, and (ii) on bacterial abundance, diversity and community structure in the absence or presence of a protist predator. In addition, this thesis questioned the impacts of species interactions and rapid trait shifts, as a response to predation and competition, on the community dynamics and stability. Our results revealed that the predator suffered more from disturbances over longer time periods. Reduced predation pressure caused a transient phase of prey release during and even after disturbances. Recovery time depended on the strength and duration of disturbances, however, coupling to an alternative resource increased the chance of fast recovery and stabilized the communities. In multi-species prey communities, bacterial abundance, diversity, and community composition were more affected by predation than by the disturbances and resource dynamics. Predator abundance, on the other hand, was strongly affected by the type of disturbance imposed. Importantly, community attributes had differential sensitivities, as reflected by their different response and recovery dynamics. Prey community dynamics varied more temporally andwere less stable under predation stress, while prey diversity increased significantly. Predation rapidly induced anti-predation traits, which altered population dynamics of both prey and predator. More importantly, predator and the resistant prey, in turn, elevated the number of direct cause-effect relationships between the community members. Our findings are not limited to the studied system and can be used to understand the dynamic response and recovery potential of many natural predator-prey or host-pathogen systems. They can be used as a base for future studies to illuminate the debates on the future communities.:Summary Zusammenfassung 1 Scope and Outline 2 General Introduction 2.1 Context dependency of community dynamics 2.2 Ecological disturbances 2.2.1 Transient dynamics and stability 2.2.2 Catastrophic shifts 2.3 Species interactions and evolutionary dynamics under environmental change 2.3.1 Species interactions and coexistence 2.4 Eco-evolutionary dynamics 2.5 Community assembly mechanisms 2.6 Dealing with complexities 2.6.1 Microbial model systems as a tool in ecology 2.6.2 Correlation, causation and the future of predictions 2.7 Aims of this study 3 Community Dynamics under Disturbances 3.1 Transient recovery dynamics of a predator-prey system 4 Interactions of Community Drivers 4.1 Interactions between predation and disturbances shape prey communities 5 Species Interactions and Evolutionary Dynamics Shaping Communities 5.1 Summary 5.2 Introduction 5.2.1 Predator-Prey Dynamics and Community Stability 5.2.2 Causal inferences 5.3 Aim of the study 5.4 Methods 5.4.1 Organisms 5.4.2 Microcosm experiments and estimation of species abundances 5.4.3 Statistical analysis 5.5 Results 5.5.1 Community dynamics 5.5.2 Dynamics of prey diversity and community stability 5.5.3 Causal links between the species dynamics 5.6 Discussion 5.7 Synopsis 6 General Discussion 6.1 Communities under disturbances: Predator{ prey dynamics 6.2 Temporal species dynamics and community assembly Synthesis and Outlook 7.1 Increasing complexity of species interactions 7.2 Going further from causal links 7.3 Metacommunities References 8 Appendix 8.1 Declaration of the authorship 8.2 Author contributions of published articles 8.3 List of publications and conference contributions 8.4 Acknowledgments 8.5 Supplementary material for Chapter 3 8.6 Supplementary material for Chapter 4 8.7 Supplementary material for Chapter