Indiana University-Purdue University Indianapolis (IUPUI) / Systems Engineering is catching pace in many segments of product manufacturing industries. Model-Based Systems Engineering (MBSE) is the formalized application of modeling to perform systems engineering activities. In order to effectively utilize the complete potential of MBSE, a methodology consisting of appropriate processes, methods and tools is a key necessity. In the last decade, several MBSE projects have been implemented in industries varying from aerospace and defense to automotive, healthcare and transportation. The Systems Modeling Language (SysML) standard has been a key enabler of these projects at many companies. Although SysML is capable of providing a rich representation of any system through various viewpoints, the journey towards adopting SysML to realize the true potential of MBSE has been a challenge. Among all, one of the common roadblocks faced by systems engineers across industries has been the software engineering-based nature of SysML which leads to difficulties in grasping the modeling concepts for people that do not possess a software engineering background. As a consequence, developing a system (or a system of systems) architecture model using SysML has been a challenging task for many engineers even after a decade of its inception and multiple successive iterations of the language specification. Being a modeling language, SysML is method-agnostic, but its associated limitations outweigh the advantages. ARCADIA (Architecture Analysis and Design Integrated Approach) is a systems and software architecture engineering method based on architecture-centric and model-based engineering activities. If applied properly, ARCADIA allows for a very effective way to model the architecture of multi-domain systems, and overcome many of the limitations faced in traditional SysML implementation. This thesis evaluates the architecture development capabilities of ARCADIA/Capella versus SysML following the Object-Oriented Systems Engineering Method (OOSEM). The study focuses on the key equivalences and differences between the two MBSE solutions from a model development perspective and provides several criteria to evaluate their effectiveness for architecture development using a conceptual case of Adaptive Cruise Control (ACC). The evaluation is based on three perspectives namely, architecture quality, ability to support key process deliverables, and the overall methodology. Towards this end, an industry-wide survey of MBSE practitioners and thought leaders was conducted to identify several concerns in using models but also to validate the results of the study. The case study demonstrates how the ARCADIA/Capella approach addresses several challenges that are currently faced in SysML implementation. From a process point of view, ARCADIA/Capella and SysML equally support the provision of the key deliverable artifacts required in the systems engineering process. However, the candidate architectures developed using the two approaches show a considerable difference in various aspects such as the mapping of the form to function, creating functional architectures, etc. The ARCADIA/Capella approach allows to develop a ‘good’ system architecture representation efficiently and intuitively. The study also provides answers to several useful criteria pertaining to the overall candidate methodologies while serving as a practitioner’s reference in selecting the most suitable approach.

Indiana University-Purdue University Indianapolis (IUPUI) / Ceramics have been extensively used in aerospace, automotive, medical, and energy industries due to their unique combination of mechanical, thermal, and chemical properties. The objective of this thesis is to develop an extrusion based ceramic 3D printing process to digitally produce a casting mold. To achieve the objective, an in-house designed ceramic 3D printer was developed by converting a filament based plastic 3D printer. For mold making applications, zircon was selected because it is an ultra-high temperature ceramic with high toughness and good refractory properties. Additionally, alumina, bioglass, and zirconia slurries were formulated and used as the feedstock material for the ceramic 3D printer. The developed 3D printing system was used to demonstrate successful printing of special feature parts such as thin-walled high aspect ratio structures and biomimetically inspired complex structures. Also, proof of concept with regard to the application of 3D printing for producing zircon molds and casting of metal parts was also successfully demonstrated. To characterize the printed parts, microhardness test, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses were conducted. The zircon samples showed an increase in hardness value with an initial increase in heat treatment temperature followed by a drop due to the development of porosity in the microstructure, caused by the decomposition of the binder. The peak hardness value for zircon was observed to be 101±10 HV0.2. Similarly, the microhardness values of the other 3D printed ceramic specimens were observed to increase from 37±3 to 112±5 HV0.2 for alumina, 23±5 to 35±1 HV0.2 for bioglass, and 22±5 to 31±3 HV0.2 for zirconia, before and after the heat-treatment process, respectively. Finally, a system model for the ceramic 3D printing system was developed through the application of the model-based systems engineering (MBSE) approach using the MagicGrid framework. Through the system engineering effort, a logical level solution architecture was modeled, which captured the different system requirements, the system behaviors, and the system functionalities. Also, a traceability matrix for the system from a very abstract logical level to the definition of physical requirements for the subsystems was demonstrated.

Aircraft developers like other development and manufacturing companies, are experiencing increasing complexity in their products and growing competition in the global market. One way to confront the challenges is to make the development process more efficient and to shorten time to market for new products/variants by using design and development methods based on models. Model Based Systems Engineering (MBSE) is introduced to, in a structured way, support engineers with aids and rules in order to engineer systems in a new way. In this thesis, model based strategies for aircraft and avionics development are studied. A background to avionics architectures and in particular Integrated Modular Avionics is described. The integrating discipline Systems Engineering, MBSE and applicable standards are also described. A survey on available and emerging modeling techniques and tools, such as Hosted Simulation, is presented and Modeling Domains are defined in order to analyze the engineering environment with all its vital parts to support an MBSE approach. Time and money may be saved by using modeling techniques that enable understanding of the engineering problem, state-of-the-art analysis and team communication, with preserved or increased quality and sense of control. Dynamic simulation is an activity increasingly used in aerospace, for several reasons; to prove the product concept, to validate stated requirements, and to verify the final implementation. Simulation is also used for end-user training, with specialized training simulators, but with the same underlying models. As models grow in complexity, and the set of simulation platforms is expanded, new needs for specification, model building and configuration support arise, which requires a modeling framework to be efficient.

This dissertation contributes to the theoretical foundations of systems engineering (SE) and exposes an unstudied SE area of definition of verification models. In practice, verification models are largely qualitatively defined based on heuristic assumptions rather than science-based approach. For example, we may state the desire for representativeness of a verification model in qualitative terms of low, medium, or high fidelity in early phases of a system lifecycle when verification requirements are typically defined. Given that fidelity is defined as a measure of approximation from reality and that the (real) final product does (or may) not exist in early phases, we are stating desire for and making assumptions of representative equivalence that may not be true. Therefore, this dissertation contends that verification models can and should be defined on the scientific basis of systems theoretic principles. Furthermore, the practice of SE is undergoing a digital transformation and corresponding desire to enhance SE educationally and as a discipline, which this research proposes to address through a science-based approach that is grounded in the mathematical formalism of systems theory. The maturity of engineering disciplines is reflected in their science-based approach, such as computational fluid dynamics and finite element analysis. Much of the discipline of SE remains qualitatively descriptive, which may suffer from interpretation discrepancies; rather than being grounded in, inherently analytical, theoretical foundations such as is a stated goal of the SE professional organization the International Council on Systems Engineering (INCOSE). Additionally, along with the increased complexity of modern engineered systems comes the impracticality of verification through traditional means, which has resulted in verification being described as broken and in need of theoretical foundations. The relationships used to define verification models are explored through building on the systems theoretic lineage of A. Wayne Wymore; such as computational systems theory, theory of system design, and theory of problem formulation. Core systems theoretic concepts used to frame the relationship-based definition of verification models are the notions of system morphisms that characterize equivalence between pairs, problem spaces of functions that bound the acceptability of solution systems, and hierarchy of system specification that characterizes stratification. The research inquisition was in regard to how verification models should be defined and hypothesized that verification models should be defined through a combination of systems theoretic relationships between verification artifacts; system requirements, system designs, verification requirements, and verification models. The conclusions of this research provide a science-based metamodel for defining verification models through systems theoretic principles. The verification models were shown to be indirectly defined from system requirements, through system designs and verification requirements. Verification models are expected to be morphically equivalent to corresponding system designs; however, there may exist infinite equivalence which may be reduced through defining bounding conditions. These bounding conditions were found to be defined through verification requirements that are formed as (1) verification requirement problem spaces that characterize the verification activity on the basis of morphic equivalence to the system requirements and (2) morphic conditions that specify desired equivalence between a system design and verification model. An output of this research is a system theoretic metamodel of verification artifacts, which may be used for a science-based approach to define verification models and advancement of the maturity of the SE discipline. / Doctor of Philosophy / We conduct verification to increase our confidence that the system design will do what is desired as defined in the requirements. However, it is not feasible to perform verification on the final product design within the full scope of the requirements; due to cost, schedule, and availability. As a result, we leverage surrogates, such as verification models, to conduct verification and determine our confidence in the system design. A challenge to our confidence in the system design exists in that we accept the representativeness of the surrogates based on faith alone; rather than scientific proof. This dissertation defines science-based approach to determining the representativeness of substitutes. In the discipline and practice of systems engineering, verification models serve as substitutes for the system design; and verification requirement problem spaces serve as substitutes the requirements. The research used mathematical principles to determine representative equivalence and to find that a combination of relationship framing is needed for sufficient selection of verification models. The framing includes relationships to the system being engineered and to the substitute conditions under which the verification model is examined relative to the conditions under which the engineered system is expected to operate. A comparison to the state of the discipline and practice to the research findings was conducted and resulted in confirming unique contribution of the dissertation research. In regard to framing the acceptability of verification models, this research established the foundations for a science-based method to advance the field of Systems Engineering.

Over the past few decades, not only have systems continued to increase in complexity, but they are expected to be delivered in the same timeframe and cost range. Technology has advanced us into what some refer to as the 4th Industrial Revolution. Digital is becoming the expectation in all areas of people's lives. Model-Based Systems Engineering (MBSE) represents the transition of systems into this new digital age, promising many improvements over the previous Document-Based Systems Engineering. This transition, however, is not simple. MBSE is a major paradigm shift for systems engineers, especially for those who have been in this field for many years. In order to work as intended, MBSE requires the participation of many different disciplines and functionalities in an organization. Gaining this level of organizational collaboration, however, is no easy task. Organizational structure and culture have intuitively been believed to be critical barriers to the successful adoption of MBSE, but little work has been done to discover what the impacts of these organizational factors are. The purpose of this research is to further explore the MBSE adoption process in the context of the organization. There were three research objectives designed to address the research question: how does organizational structure influence the adoption and implementation of MBSE? Research objective one was: relate organizational structure characteristics to MBSE adoption and implementation measures. Research objective two was: discover how organizational factors contribute to decisions made and other aspects of the MBSE adoption process. Research objective three was: connect different organizational structure and adoption variables together to derive critical variables in the adoption process. Research objective one was carried out using a survey as the instrument. The objective of the survey was to examine what the effects of organizational structure are on MBSE adoption and implementation. Organizational structure was represented by seven variables: Size, Formalization, Centralization, Specialization, Vertical Differentiation, Flexibility, and Interconnectedness. These are different characteristics of organizational structure that can be measured on a scale. MBSE adoption and implementation was represented by one adoption and three implementation variables. These include Adoption Process, Maturity of MBSE, Use of MBSE, and Influence on organizational outcomes. A total of 51 survey responses were received that met the inclusion criteria. Factor analysis was done for variables with multi-item measures. The factors were then analyzed using pairwise correlations to determine which relationships were significant. Formalization, Flexibility, and Interconnectedness were found to have positive correlations with adoption and implementation variables. Size and Vertical Differentiation had a negative correlation with Use of MBSE (implementation). Centralization was found to have negative correlations with adoption and implementation. Specialization did not have any significant correlations. Research objective two utilized semi-structured interviews as the main instrument. Survey participants had the opportunity to provide more detailed explanations of their organizations' experiences in the form of follow-up interviews. Eighteen survey participants agreed to this follow-up interview focused on MBSE adoption. Two of the participants shared failed adoption experiences, with the rest were at various stages of the adoption process. One of the most emergent themes out of the interviews was the idea of integration. Integration needs to occur at the organizational level, and the technical level. The technical level refers to the fact that tools, models, and/or data repositories need to be linked together in some way. Integration also has to occur at the organizational level, because a lot of different functional areas need to come together for MBSE. The way that organizations can address the issue of integration is through coordination mechanisms. The ultimate goal is to achieve implicit coordination through the use of connected models, but getting to that point will require coordination between different subunits. Interview responses were evaluated for coordination mechanisms, or situations that showed a distinct lack of a coordination mechanism. The lack of coordination mechanisms largely consists of a lack of standardization, lack of communication between subunits, and issues of authority. The final research objective of this work was carried out through a causal analysis using the data obtained from the survey and interviews. The purpose of this analysis was to visualize and better understand the adoption process. According to the calculated measures of centrality, the important nodes in this model are Improved organizational outcomes, Coordination between subunits, Projects use tools/methods, and People willing to use tools. Improved organizational outcomes is part of a key loop in the causal model. Improved organizational outcomes contributes to leaders and employees' willingness to support and use MBSE methods and tools, which contribute to actual use of tools and methods. This creates more Improved organizational outcomes, completing the loop. The survey results showed that Formalization, Decentralization, Flexibility, and Interconnectedness all have positive correlations with the Influence on organizational outcomes. So these organizational structure components are external factors that can be used to positively impact the adoption loop. Overall, this work provided several contributions to the field regarding the MBSE adoption process in an organizational setting. Organizational structure was shown to have significant correlations with adoption and implementation of MBSE. Coordination mechanisms were identified as a method to achieve integration across different functional areas of the organization. Improved organizational outcomes was shown to be a critical variable in the adoption process as an avenue for organizational structure factors to have a positive effect on the adoption process. / Doctor of Philosophy / Over the past few decades, not only have systems continued to increase in complexity, but they are expected to be delivered in the same timeframe and cost range. Technology has advanced us into what some refer to as the 4th Industrial Revolution. Digital is becoming the expectation in all areas of people's lives. Model-Based Systems Engineering (MBSE) represents the transition of systems into this new digital age, promising many improvements over the previous Document-Based Systems Engineering. This transition, however, is not simple. MBSE is a major mindset change for systems engineers, especially for those who have been in this field for many years. In order to work as intended, MBSE requires the participation of many different disciplines and functionalities in an organization. Gaining this level of organizational collaboration, however, is no easy task. Organizational structure and culture have intuitively been believed to be critical barriers to the successful adoption of MBSE, but little work has been done to discover what the impacts of these organizational factors are. This research looks into how organizational structure may have an impact on MBSE adoption and implementation. This research was carried out with the use of three different methods: an online survey, semi-structured interviews, and a causal analysis. The data obtained from the survey and interviews was used to construct a causal model depicting the MBSE adoption process. Overall, this work provided several contributions to the field regarding the MBSE adoption process in an organizational setting. Organizational structural variables were shown to have significant correlations with adoption and implementation of MBSE. Formalization, Flexibility, and Interconnectedness were found to have positive correlations with adoption and implementation variables, while Centralization had negative correlations with adoption and implementation. Coordination mechanisms were identified as a method to achieve integration across different functional areas of the organization. Interview responses were evaluated for coordination mechanisms, or situations that showed a distinct lack of a coordination mechanism. The lack of coordination mechanisms largely consists of a lack of standardization, lack of communication between subunits, and issues of authority. The causal analysis showed that Improved organizational outcomes, Coordination between subunits, Projects use tools/methods, and People willing to use tools were the critical variables in the MBSE adoption process.

Este trabalho desenvolve um método para a comparação de soluções logísticas de armazenamento e recuperação, com aplicações em centros de distribuição, depósitos, armazéns e demais estruturas equivalentes. Tais soluções podem implicar desde o uso de paleteiras manuais e empilhadeiras contra-balanceadas, até em arranjos mais complexos, envolvendo trans-elevadores operando em corredores de prateleiras com vários metros de altura. A literatura existente para o design e a escolha de tais soluções ressalta o prevalecimento de métodos proprietários e ad-hoc, auxiliados por ferramentas de software demasiadamente genéricas. Assim, o método aqui proposto é elaborado seguindo os princípios da Engenharia de Sistemas Baseada em Modelos (MBSE), sendo expresso através da linguagem OMG SysMLTM, e montado com o auxílio de ferramenta de software CASE (computer aided systems engineering) disponível comercialmente. Utilizando-se das técnicas mencionadas, este trabalho demonstra o passo-apasso da construção do método proposto, incluindo a formulação de um template de requisitos e de um modelo de referência, orientado a objetos, para sistemas logísticos de armazenamento e recuperação. Concluída a apresentação do método, o mesmo é aplicado em dois exemplos de estudos de viabilidade (trade-studies) que determinam soluções ótimas para um dado conjunto de requisitos de negócio. No primeiro exemplo tem-se como fator limitante o no de endereços de armazenamento, e no segundo a área disponível para construção do armazém. O principal resultado obtido com esse trabalho é capacidade de simular, em um único ambiente, escolhas de soluções logísticas de armazenamento que consideram parâmetros do sistema como um todo, e não apenas de seus sub-sistemas isoladamente. Isto tornou possível mensurar como alterações nas especificações de um dado ponto de vista, como o estrutural, impactam na satisfação dos requisitos de outros pontos de vista, como o dinâmico ou financeiro. A MBSE, entretanto, ainda não pode ser considerada uma disciplina madura. As ferramentas de software que a ela dão suporte, bem como as listas de melhores práticas de suas aplicações estão em constante evolução e aprimoramento. Dessa forma, a aplicação dos princípios da MBSE no design e seleção de soluções logísticas de armazenamento, com adoção da orientação a objetos, pode ser tida como uma ideia inovadora. / This work presents a method for warehouse storage solutions comparison. The existing research regarding the design and selection of such logistic solutions highlights the predominance of ad-hoc procedures, as well as the use of generic software tools. Therefore, the method herein presented shall be developed according to the model-based systems engineering (MBSE) principles, being describe through the system modeling language (SysML), and built inside a computer-aided system engineering (CASE) software tool, commercially available. The method\'s steps shall be thoroughly detailed, including the creation of a reference model for warehouse storage systems, and its further use in trade studies execution. Once the method is properly described, its validation is demonstrated through two case studies designed to compare storage solutions according to the number of pallet-positions oered, and its dimensional footprint. This work\'s main achievement is the possibility to simulate, in a single environment, warehouse storage solution\'s options that take into account parameters of the system as a whole, and not only its sub-systems separately. With that, it is possible to measure how changes in the specifications of a given view point, such as structural, impact the requirement\'s satisfaction of other view points, such as dynamic or financial. The MBSE, however, still can not be considered a mature discipline. The software tools that support it, as well as the lists of best practices of its applications are constantly evolving and improving. Thus, the application of MBSE\'s principles in the design, and comparison, of warehouse storage solutions, with the adoption of object orientation, can be considered an innovative idea.

Este trabalho desenvolve um método para a comparação de soluções logísticas de armazenamento e recuperação, com aplicações em centros de distribuição, depósitos, armazéns e demais estruturas equivalentes. Tais soluções podem implicar desde o uso de paleteiras manuais e empilhadeiras contra-balanceadas, até em arranjos mais complexos, envolvendo trans-elevadores operando em corredores de prateleiras com vários metros de altura. A literatura existente para o design e a escolha de tais soluções ressalta o prevalecimento de métodos proprietários e ad-hoc, auxiliados por ferramentas de software demasiadamente genéricas. Assim, o método aqui proposto é elaborado seguindo os princípios da Engenharia de Sistemas Baseada em Modelos (MBSE), sendo expresso através da linguagem OMG SysMLTM, e montado com o auxílio de ferramenta de software CASE (computer aided systems engineering) disponível comercialmente. Utilizando-se das técnicas mencionadas, este trabalho demonstra o passo-apasso da construção do método proposto, incluindo a formulação de um template de requisitos e de um modelo de referência, orientado a objetos, para sistemas logísticos de armazenamento e recuperação. Concluída a apresentação do método, o mesmo é aplicado em dois exemplos de estudos de viabilidade (trade-studies) que determinam soluções ótimas para um dado conjunto de requisitos de negócio. No primeiro exemplo tem-se como fator limitante o no de endereços de armazenamento, e no segundo a área disponível para construção do armazém. O principal resultado obtido com esse trabalho é capacidade de simular, em um único ambiente, escolhas de soluções logísticas de armazenamento que consideram parâmetros do sistema como um todo, e não apenas de seus sub-sistemas isoladamente. Isto tornou possível mensurar como alterações nas especificações de um dado ponto de vista, como o estrutural, impactam na satisfação dos requisitos de outros pontos de vista, como o dinâmico ou financeiro. A MBSE, entretanto, ainda não pode ser considerada uma disciplina madura. As ferramentas de software que a ela dão suporte, bem como as listas de melhores práticas de suas aplicações estão em constante evolução e aprimoramento. Dessa forma, a aplicação dos princípios da MBSE no design e seleção de soluções logísticas de armazenamento, com adoção da orientação a objetos, pode ser tida como uma ideia inovadora. / This work presents a method for warehouse storage solutions comparison. The existing research regarding the design and selection of such logistic solutions highlights the predominance of ad-hoc procedures, as well as the use of generic software tools. Therefore, the method herein presented shall be developed according to the model-based systems engineering (MBSE) principles, being describe through the system modeling language (SysML), and built inside a computer-aided system engineering (CASE) software tool, commercially available. The method\'s steps shall be thoroughly detailed, including the creation of a reference model for warehouse storage systems, and its further use in trade studies execution. Once the method is properly described, its validation is demonstrated through two case studies designed to compare storage solutions according to the number of pallet-positions oered, and its dimensional footprint. This work\'s main achievement is the possibility to simulate, in a single environment, warehouse storage solution\'s options that take into account parameters of the system as a whole, and not only its sub-systems separately. With that, it is possible to measure how changes in the specifications of a given view point, such as structural, impact the requirement\'s satisfaction of other view points, such as dynamic or financial. The MBSE, however, still can not be considered a mature discipline. The software tools that support it, as well as the lists of best practices of its applications are constantly evolving and improving. Thus, the application of MBSE\'s principles in the design, and comparison, of warehouse storage solutions, with the adoption of object orientation, can be considered an innovative idea.

L'Ingénierie des Systèmes (IS) est une approche pluridisciplinaire et collaborative pour mener à bâtir et structurer la conception puis la réalisation et le développement de systèmes complexes. L’IS repose à la fois sur une approche processus et sur la mise en oeuvre de modèles de systèmes s'appuyant de fait dans un contexte basé ou dirigé par des modèles. On parle alors d’Ingénierie Système Basée sur des Modèles (ISBM ou Model based Systems Engineering MBSE). L’ISBM introduit des concepts, méthodes et techniques pour construire et gérer des modèles. Elle a pour objectif l’atteinte et l’amélioration de leur qualité afin de procurer aux parties prenantes un degré de confiance jugé suffisant pour aider la prise des décisions de conception, d'amélioration et de réalisation. Ces décisions conditionnent le fonctionnement, la sûreté, la sécurité, les coûts, et plus généralement tout un ensemble de propriétés attendues à la fois du modèle comme du système modélisé, tout au long de la phase aval de l’ingénierie et de développement, jusqu’à la réalisation et au déploiement du système. La qualité des modèles est obtenue au travers des processus de Vérification et Validation (V&V). Les objectifs sont alors d’assurer que les modèles soient cohérents, bien formés, bien construits et représentés correctement. En effet, aux yeux des parties prenantes, les modèles doivent être fiables, fidèles et pertinents au regard des besoins des concepteurs, représentant aussi précisément que possible le point de vue du système en cours de conception. Des langages de modélisation dit « métier » (Domain Specific Modelling Languages ou DSML) sont spécifiquement créés pour pouvoir fournir des représentations i.e. des modèles dans les différents points de vue sur le système. Un DSML est basé sur une syntaxe et sur une sémantique. La sémantique de ces langages est en général fournie par des approches externes (vérificateurs de modèles). Ces dernières sont, à notre sens, une limitation clé pour le déploiement des stratégies de V&V dans le contexte de l’ISBM. En réponse à cette limitation, la contribution conceptuelle de cette thèse est présentée sous la forme d’un nouveau langage de métamodélisation, nommé xviCore (noyau exécutable, vérifiable et interopérable). xviCore fournit les concepts et les principes pour définir puis vérifier et valdier la syntaxe et la sémantique en phase de construction de tels DSML en combinant trois métalangages : un métalangage orienté objet pour la conception de la partie syntaxique, un métalangage pour la conception du comportement et un métalangage pour la conception de propriétés formelles. La contribution méthodologique de ces travaux permet ensuite le déploiement d’une stratégie de V&V «directe» en lieu et place des traditionnelles approches externes. Elle est basée sur la simulation et la preuve formelle de propriétés. Le mécanisme de simulation permet d’observer le comportement des modèles de systèmes au travers de leur exécution, tandis que le mécanisme de preuve permet de spécifier et ensuite de vérifier des propriétés formelles. La contribution technique se compose d’un ensemble des plugins Eclipse qui implémentent le métalangage xviCore, le mécanisme de simulation et le mécanisme de la preuve formelle. / Systems Engineering (SE) is an interdisciplinary and collaborative approach for successful design and management of large scale complex systems. Among other principles, SE promotes and mandates a model-based (or model-driven) approach for all stages of system design processes, denoted Model-Based Systems Engineering (MBSE). This implies concepts, techniques and tools for creating and managing various systems models for the purpose of stakeholders, and for reaching and improving the quality of models helping then stakeholders during decision-making processes, to make decisions faster and efficiently with enough confidence. Indeed, these decisions impact all along the downstream phases of system engineering and development until the realization and deployment of the real system, its functioning, safety, security, induced costs and so on. In this work, a particular attention is given to model verification and validation (V&V). The goals are to assure prior to decision-making processes, first, that models are coherent, well-formed and correctly build and represented, and second, that they are trustworthy and relevant, representing as accurately as possible the viewpoints of a system under design as expected by stakeholders.Such models provide stakeholders with confidence and trust, aiding them in making, but also in arguing decisions. Models are created by using modeling languages that are specifically tailored for a given viewpoint of a system, denoted Domain Specific Modeling Languages (DSMLs).The basic principles on which a DSML is based are its syntax and its semantics, but current DSMLs have been more studied from the syntactical point than from the semantical one that is often neglected or, when needed, provided by means of translating the DSML into third party formalisms. This is the key limitation preventing the deployment of a successful V&V strategy in MBSE context. To overcome this shortcoming, this thesis proposes first a conceptual contribution consisting of a new metamodeling language, called eXecutable, Verifiable and Interoperable Core (xviCore), allowing stakeholders to build DSMLs (called xviDSMLs), that along with their syntax also integrates semantics. Our solution combines, three meta-languages, an object-oriented metamodeling language for the specification of the syntactical part with a formal behavioral modeling language and a property modeling language for the semantical part. The methodological contribution of this work allows the deployment of successful V&V strategies allowing for direct (without transformation) model verification by simulation and properties proof. We propose a mechanism to simulate the expected behavior of a SoI through model execution based on the blackboard-based communication model, and a mechanism for specification and verification of formal properties. The technical contribution consists of an Eclipse-EMF deployable plug-in that implements the metamodeling language xviCore and the mechanisms for simulation and formal property verification.

The master's thesis describes how complexity measurement can enhance product development or design processes in collaboration with Scania CV AB. Scania has a strong track record in vehicle modularization and thus wanted to investigate the possibility of using complexity measures when architecting, developing, and maintaining complex engineering products such as electrified or self-driving trucks and buses to gain various types of benefits. The section YMPI at Scania, where the project is conducted, had, however, little experience in complexity measurements wants to identify and investigate which complexity measure effectively captures the complexity of a complex system. A fairly complicated industrial case of a conceptual Battery Electric Vehicle (BEV) variant was utilized to demonstrate the newly proposed complexity metric methodology and demonstrate its ability to determine the technical complexity of a system. As a result, the thesis author found a specific case study at Scania and used appropriate methodologies to determine the complexity of the chosen subsystem using the newly proposed complexity measure. This was done by adapting the DSM (Design Structure Matrix) before clustering it with the IGTA++ clustering algorithm. The proposed complexity metric yields a higher complexity number when compared to the traditional product complexity metric.  Another purpose of the thesis was to answer the research questions and conduct a literature review in the field of Model Based System Engineering and product architecting to define the state-of-the-art. The thesis concludes that the newly proposed complexity metric, when implemented on the chosen subsystem, yields a higher complexity number when compared to the number obtained from product complexity, implying that including the directions of an interaction between the components and taking into account the active interacting components improves the accuracy of the complexity measure.  Therefore, it is recommended to Scania to use this proposed method to find the complexity of the system and to compare how the system gets complex when incorporating new technologies or modifying the system or product architecture, as well as to utilize this as a safety and a performance factor for a system. / I examensarbetet beskrivs hur komplexitetsmätning kan förbättra produktutvecklings- eller designprocesser i samarbete med Scania CV AB. Scania har en stark erfarenhet av fordonsmodularisering och önskade därför undersöka möjligheten att använda komplexitetsmått för arkitektur, utveckling och underhåll av komplexa tekniska produkter som elektrifierade eller självkörande lastbilar och bussar för att få olika typer av fördelar. Sektionen YMPI på Scania, där projektet genomförs, hade dock lite erfarenhet av komplexitetsmått och sökte identifiera och undersöka vilket komplexitetsmått som effektivt fångar komplexiteten hos ett komplext system. Ett ganska komplicerat industriellt fall av en konceptuell variant av ett elektriskt batterifordon (BEV) användes för att demonstrera den nyligen föreslagna metoden för komplexitetsmätning och för att visa dess förmåga att fastställa ett systems tekniska komplexitet. Som ett resultat av detta hittade avhandlingsförfattaren en specifik fallstudie hos Scania och använde lämpliga metoder för att bestämma komplexiteten hos det valda delsystemet med hjälp av det nyligen föreslagna komplexitetsmåttet. Detta gjordes genom att anpassa DSM (Design Structure Matrix) innan den klustrades med klusteralgoritmen IGTA++. Det föreslagna komplexitetsmåttet ger ett högre komplexitetstal jämfört med det traditionella produktkomplexitetsmåttet.  Ett annat syfte med avhandlingen var att besvara forskningsfrågorna och genomföra en litteraturstudie inom området modellbaserad systemteknik och produktarkitektur för att definiera den senaste tekniken. I avhandlingen dras slutsatsen att det nyligen föreslagna komplexitetsmåttet, när det tillämpas på det valda delsystemet, ger ett högre komplexitetstal jämfört med det tal som erhålls från produktkomplexitet, vilket innebär att om man inkluderar riktningarna för en interaktion mellan komponenterna och tar hänsyn till de aktiva interagerande komponenterna förbättras komplexitetsmåttets noggrannhet.  Därför rekommenderas Scania att använda den föreslagna metod för att fastställa systemets komplexitet och jämföra hur systemet blir mer komplext när ny teknik införlivas eller när system- eller produktarkitekturen ändras, samt att använda detta som en säkerhets- och prestandafaktor för ett system.

Globale Krisen, Rohstoffengpässe oder Preisschwankungen stellen die globalisierten Lieferkettensysteme der westlichen Produzenten vor große Herausforderungen. Das Konzept der Kreislaufwirtschaft ist eine Möglichkeit, sich angesichts dieser Herausforderungen robuster zu positionieren, um weniger abhängig von äußeren Einflüssen zu sein. Die größte Hürde bei dem Aufbau von Netzwerken für Kreislaufwirtschaftsprozesse ist die Identifikation von potentiellen Partnern auf Basis von Stoffstrommodellen. Ein erfolgreiches Mapping ist von vielen Faktoren abhängig. Aktuell existiert kein Ansatz, um die Stoffströme so zu modellieren, dass die Darstellung und Berechnung für eine Partnersuche in der Kreislaufwirtschaft geeignet ist. Um der Komplexität, sowohl der Stoffstrommodellierung, als auch der Partnersuche gerecht zu werden, wird hier ein MBSE-Ansatz gewählt - ein überlegener Modellierungsansatz im Detaillierungsgrad und der Adaptionsfähigkeit. Das Modell verknüpft die 3 Hauptelemente der Wertstromanalyse (Produktionsprozess, Materialfluss und Geschäftsprozess) und ermöglicht dadurch neuartige Kennzahlen zu ermitteln. Diese Kennzahlen und die detaillierte Modellierung schaffen eine verbesserte Informationslage, auf Basis derer die Effektivität der Partnersuche in der Kreislaufwirtschaft signifikant gesteigert wird. Nach einer theoretischen Herleitung der Modellierungslogik und der Erweiterung des bestehenden Ansatzes der nachhaltigen Wertstromanalyse (engl. Sustainable Value Stream Mapping – Sus-VSM) wird anhand eines Beispiels das MBSE-Modell implementiert und validiert. Dieser MBSE-Ansatz besitzt das Potential, die Beschreibung industrieller Produktions- und Herstellungsprozesse erheblich zu verfeinern und dadurch Analysen und Berechnungen zu optimieren, was zu einer besseren Vernetzung der Industrie führt. Die dadurch identifizierten industriellen Symbiosen fördern die Kreislaufwirtschaft maßgeblich und helfen Ressourcen nachhaltiger zu nutzen.