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The Digital Business Ecosystem (DBE) theory has evolved to facilitate the functioning of open business networks by adopting the ecosystem paradigm from nature in a shared digital environment. While it enables exhibiting diverse interests, it also places high demands on managing the DBE’s resilience. The current research lacks support for how a DBE-based business model can be integrated with its supporting information system’s data structure to enable the design and monitoring of resilience for indicating the needed adaptations caused by changes in DBE’s actors, their engagement or performance balance. We propose and instantiate a meta-model that describes the DBE’s entities relevant to its design using the CIVIS ecosystem. The meta-model provides a foundation for a modelling language for the management of the resilience of DBE.

Operating high-speed trains imposes excessive vibrations to bridges raising concerns about their safety. In this context, it was shown that some conventional design methods such as those related to the running safety suffer from a vague scientific background questioning their reliability or optimality. Therefore, the current article is devoted to updating the conventional design methodology, using Reliability-Based Design Optimization (RBDO) to propose the minimum allowable mass and stiffness which assures satisfying the target reliability. These proposed minimum design values can conceptually replace the conventional partial safety factor-based design method for running safety without the need for dynamic analysis. If the mass and stiffness resulting from the control of other limit states meet the proposed minimum values, the desired target reliability for running safety will be assured. This is achieved by adaptively training Kriging meta-models as a surrogate for the computational models decoupling the RBDO problem. In this regard, a new stopping criteria is proposed using mis-classification ratio of the cross-validated model; which reduces the generalization error of the trained meta-model and consequently the estimated failure probability. Moreover, due to the dependence of the design variables, the Copula concept is used to refine the augmented space and reformulate the RBDO problem., QC 20230710

Since 2017, Dutch flood defences are assessed according to new safety standards. These standards are based on flooding probabilities and rely on several assumptions and approximations. There are concerns that the combination of these assumptions leads to conservative results. Recently computed probabilities of failure are often much higher than expected by dike managers and the outcomes of former assessment methods. This conservative bias results in a large and expensive reinforcement task in the coming years which can be reduced by improving the current assessment procedure. One of the reasons for the current conservatism is the assumption of mutual independence of dike sections and failure mechanisms. Currently, the different elements are assessed independently, while failure mechanisms and failure at different dike sections are likely to occur during the same extreme load event. Furthermore, correlations in space and between different parameters are present within the subsoil characteristics. Neglecting these correlations results in rather high estimations of the failure probabilities. The aim of this thesis is to investigate how correlations affect the reliability assessment of a dike trajectory. To achieve this, an integral, full probabilistic model is developed that enables simultaneous assessment of dike sections and failure mechanisms while accounting for uncertainties and (spatial) correlations within the model input. The model is based on Monte Carlo simulation. The failure probability of a dike trajectory is computed by counting failure if one or more limit state function 푍푗,푘 for failure mechanism 푗 of dike section 푘 returns a negative realisation. Correlations between the model input parameters are provided by means of a Gaussian copula. A particular aspect of the model is the implementation of metamodeling for the assessment of macrostability. This failure mechanism cannot be described by an analytical limit state function that i, Civil Engineering | Hydraulic Engineering | Coastal Engineering

’Flight’ is a program that uses flight mechanics to estimate the flight range of birds. This program, used by ornithologists, is only available for Windows OS. It requires manual imputation of body measurements and constants (one observation at a time) and this is time-consuming. Therefore, the first task is to implement the methods in R, a programming language that runs on various platforms. The resulting package named flying, has three advantages; first, it can estimate flight range of multiple bird observations, second, it makes it easier to experiment with different settings (e.g. constants) in comparison to Flight and third, it is open-source making contribution relatively easy. Uncertainty and global sen- sitivity analyses are carried out on body measurements separately and with various con- stants. In doing so, the most influential body variables and constants are discovered. This task would have been near impossible to undertake using ’Flight’. A comparison is made amongst the results from a crude partitioning method, generalized additive model, gradi- ent boosting machines and quasi-Monte Carlo method. All of these are based on Sobol’s method for variance decomposition. The results show that fat mass drives the simulations with other inputs playing a secondary role (for example mechanical conversion efficiency and body drag coefficient).

Gamification is increasingly used to build solutions for driving the behaviour of target users' populations. Gameful systems are typically exploited to keep users' involvement in certain activities and/or to modify an initial behaviour through game-like elements, such as awarding points, submitting challenges and/or fostering competition and cooperation with other players. Gamification mechanisms are well-defined and composed of different ingredients that have to be correctly amalgamated together; among these we find single/multi-player challenges targeted to reach a certain goal and providing an adequate award for compensation. Since the current approaches are largely based on hand-coding/tuning, when the game grows in its complexity, keeping track of all the mechanisms and maintaining the implementation can become error-prone and tedious activities. In this paper, we describe a multi-level modelling approach for the definition of gamification mechanisms, from their design to their deployment and runtime adaptation. The approach is implemented by means of JetBrains MPS, a text-based meta-modelling framework, and validated using two gameful systems in the Education and Mobility domains.

Aerospace Engineering

Traditional object-oriented programming languages only support two logical domain classification levels, i.e. classes and objects. However, if the problem involves more than two classification levels, then to model a multi-level scenario within two classification levels, a mapping approach is required which introduces accidental complexity and destroys the desirable property of “direct mapping”. Therefore “Multi-level modeling” was proposed. It supports an unbounded number of classification levels, that can support “direct mapping” without introducing accidental complexity. Many supporting features have been proposed for “multi-level” modeling such as “deep instantiation”, potency, clabjects, etc. To date most of the research effort was focusing on the entities (clabjects), while the relationships between entities were receiving much less attention and remained under-explored. The “Melanee” tool was developed to support multi-level modeling both for academics and practitioners. “Melanee” supports an unbounded number of classification levels for domain modeling and it treats relationships like clabjects. It mainly supports “constructive modeling” by creating models using a “top-down” approach, whereas “explanatory modeling”, which is creating models using “bottom-up” approach, is not well supported and lacks support to ensure the integrity of the created models. Hence, to further explore relationships in multi-level modeling and to provide a better modeling environment, there are two main focuses in this thesis: First, based on existing, I further explore relationships between entities and extend the LML (Level Agnostic Modeling Language) supported by Melanee accordingly. Second, I extend Melanee’s functionality to support “explanatory modeling”. Considering that Melanee is an open source tool I first discuss Melanee’s structure and its principles in order contribute to future extensions to Melanee. The knowledge of Melanee is currently known by its principle develop

Usually, enterprise models consider different aspects and include different abstraction levels of enterprises. It is hence challenging to integrate these models and to maintain their consistency. In the light of these challenges, ontologies seem to be relevant to complement enterprise models since they are intended to support communication, computational inference, consistency checking, querying, and the organization of knowledge. In our contribution, we demonstrate that Enterprise modelling can benefit from these characteristics. In order to check feasibility and pertinence of ontology-based Enterprise Models, we selected the goal modelling part and its relations to actors and resources from the “For Enterprise Modelling” (4EM) method. In more detail, this paper provides (1) a formal OWL representation of the 4EM Goals meta-model; (2) a discussion of goal relations regarding transitivity and domain specific inference; (3) a formalization of the discussed inference rules; and (4) an analysis of an exemplary goals model instance. This paper extends earlier work on the topic by the introduction of inter-model relations, a discussion of formalization alternatives, and a comparison of query results with and without ontology-based reasoning.

Net primary production (NPP) serves as an indicator for plant-based resources such as food, timber and biofuel for human appropriation. It is defined by the annual production of plant matter and is mainly controlled by climate and human activities. Climate change in combination with human activities is altering NPP. As the controls of NPP are expected to further change in the future, it is vital to investigate alterations in NPP and their magnitudes. The impacts of climate change and human activities on NPP can be explored in integrated assessment (IA) frameworks, where sectoral models are coupled and interact rapidly. For such frameworks, parsimonious models are desired because they enable rapid estimates and facilitate easy model coupling for explorations of multiple global change scenarios (i.e. large volumes of data). This thesis aims to advance parsimonious modelling techniques for quantifying current and future NPP on land. This is accomplished by developing and testing rapid models that facilitate easy model coupling to explore the impacts of multiple global change scenarios on NPP. The model development is based on the meta-modelling concept, which can be applied to simplify the dynamic vegetation model LPJ-GUESS in a parsimonious model. For this, multiple climate change and [CO2] perturbations are applied to LPJ-GUESS to simulate NPP. The NPP data are then used to define biophysically motivated relationships between NPP and the driving climate variables along with [CO2]. The relationships are then combined in a synergistic function – the meta-model. Thereafter, the meta-models are assessed for their performance in estimating NPP by comparing them to LPJ-GUESS NPP simulations, to independent field observations and to NPP experiments under enriched [CO2] on biome level. The results provide confidence in the modelled NPP estimates for the most productive biomes, which are important for global quantifications of NPP. The meta-models capture NPP enhancement unde

In geotechnical applications, mechanical properties of soil vary spatially within the soil mass and they are often represented by random fields. When data at certain locations of the soil mass are available, conditional random fields may be used to incorporate them. In this paper, we combine conditional random fields with sparse polynomial chaos expansions to analyze response quantities with otherwise too expensive Monte Carlo-based techniques, such as reliability and sensitivity analysis.

This master thesis looks at the use of business capabilities within enterprisearchitecture, and investigates how the concept is used within the Swedish pension managingcompany Folksam. Based on interviews with stakeholders an enterprise architecture metamodelcentred on the business capability is constructed. The meta-model is then edited andrevised according to a questionnaire aimed at removing irrelevant elements, and a secondset of interviews discussing a capability's health status and well being. This second set ofinterviews resulted in the removal of elements not aecting the well being of a capability.The nal meta-model has the business capability and the capability health status at itscore. It consists of the Capability element, with two attributes, surrounded by nine otherelements connected by eleven relations in total., Detta examensarbete undersoker hur verksamhetsformagor anvandsinom enterprisearkitektur, och vidare hur formage-konceptet anvands pa det svenska pensionsforetaget Folksam. Baserat pa intervjuer med intressenter skapas en metamodell medverksamhetsformagan i centrum. Metamodellen revideras och andras sedan enligt ett frageformular vars mal var att ta bort ej relevanta element, och enligt en andra omgang intervjuerdar en formagas halsa diskuteras. Denna andra omgang intervjuer resulterade i att elementsom inte paverkade formagans halsa togs bort. Den slutgiltiga metamodellen har verksamhetsformagan och dess halsostatus i fokus. Den bestar av formage-elementet, med tvaattribut, omgardat av nio andra element som binds ihop av totalt elva olika relationer.

Usually, enterprise models consider different aspects and include different abstraction levels of enterprises. The application of ontologies as conceptual bases that can clarify relations within and between these abstraction levels is believed to be helpful. This paper investigates the use of ontologies for formalizing enterprise modelling languages and enriching their semantics. The aim is to transform enterprise models into ontologies based on a mapping of the enterprise models’ meta-model into a semantically corresponding ontology. The ontology representation then is used to check logical consistency and to infer new facts regarding the implications of the model beyond what would be possible with a visual modelling language. In order to check feasibility and pertinence of our approach, we selected the goal modelling part of the 4EM method. This paper provides (1) a formal OWL representation of the 4EM goals meta-model; (2) a systematization of transitive goal properties; (3) a set of SWRL rules expressing these transitivity; and (4) an analysis of exemplary goals model instances.

This paper investigates important issues in three types of safety assessment methodologies commonly applied for Nuclear Power Plants (NPP). These methodologies are i) dynamic probabilistic safety assessment (DPSA) where application of genetic algorithm (GA) is shown to improve the efficiency of the analysis, ii) deterministic safety assessment (DSA) with meta model representation of the system using pre-performed computational fluid dynamics (CFD) code and iii) vulnerability search (e.g. identification of accident scenarios in an NPP) with application of neural network (NN). The use of advanced computational tools and methods such as genetic algorithms, neural networks and parallel computations improve the efficiency of safety analysis. To achieve the best effect, these advanced technologies are to be integrated with existing classical methods of safety analysis of the NPP., QC 20150414

In dieser Dissertation, schaue ich auf objekt-orientierte Metamodellierung und wie sie verwendet werden kann, um Computersprachen zu beschreiben. Dabei, fokussiere ich mich nicht nur auf die Beschreibung von Sprachen, sondern auch auf die Verwendung von Sprachbeschreibungen zur automatischen Erzeugung von Sprachwerkzeugen aus Sprachbeschreibungen. Ich nutze die Idee von Metasprachen und Metawerkzeugen. Metasprachen werden verwendet um bestimmte Sprachaspekte, wie Notationen und Semantiken, zu beschreiben, und Metawerkzeuge werden verwendet um Sprachwerkzeuge wie Editoren und Interpreter aus entsprechenden Beschreibungen zu erzeugen. Diese Kombination von Beschreibung und automatischer Entwicklung von Werkzeugen ist als Domänenspezifische Modellierung (DSM) bekannt. Ich verwende DSM basierend auf objekt-orientierter Metamodellierung zur Beschreibung der wichtigen Aspekte ausführbarer Computersprachen. Ich untersuche existierende Metasprachen und Metawerkzeuge für die Beschreibung von Sprachvorkommen, ihrer konkreten Repräsentation und Semantik. Weiter, entwickle ich eine neue Plattform zur Beschreibung von Sprachen basierend auf dem CMOF-Modell der OMG MOF 2.x Empfehlungen. Ich entwickle eine Metasprache und Metawerkzeug für textuelle Notationen. Schlussendlich, entwickle ich eine graphische Metasprache und Metawerkzeug zur Beschreibung von operationaler Semantik von Computersprachen. Um die Anwendbarkeit der vorgestellten Techniken zu prüfen, nehme ich SDL, die Specification and Description Language, als einen Archetypen für textuell notierte Sprachen mit ausführbaren Instanzen. Für diesen Archetyp zeige ich, dass die präsentierten Metasprachen und Metawerkzeuge es erlauben solche Computersprachen zu beschreiben und automatisch Werkzeuge für diese Sprachen zu erzeugen., In this thesis, I look into object-oriented meta-modelling and how it can be used to describe computer languages. Thereby, I do not only focus on describing languages, but also on utilising the language descriptions to automatically create language tools from language descriptions. I use the notion of meta-languages and meta-tools. Meta-languages are used to describe certain language aspects, such as notation or semantics, and meta-tools are used to create language tools, such as editors or interpreters, from corresponding descriptions. This combination of describing and automated development of tools is known as domain specific modelling (DSM). I use DSM based on object-oriented meta-modelling to describe all important aspects of executable computer languages. I look into existing meta-languages and meta-tools for describing language utterances, their concrete representation, and semantics. Furthermore, I develop a new platform to define languages based on the CMOF-model of the OMG MOF 2.x recommendations. I develop a meta-language and meta-tool for textual language notations. Finally, I develop a new graphical meta-language and meta-tool for describing the operational semantics of computer languages. To prove the applicability of the presented techniques, I take SDL, the Specification and Description Language, as an archetype for textually notated languages with executable instances. For this archetype, I show that the presented meta-languages and meta-tools allow to describe such computer languages and allow to automatically create tools for those languages.

A fully functional meta-model co-simulation environment that supports integration of many different simulation tool specific models into a co-simulation is described in this paper. The continuously increasing performance of modern computer systems has a large influence on simulation technologies. It results in more and more detailed simulation models. Different simulation models typically focus on different parts (sub-systems) of the complete system, e.g., the gearbox of a car, the driveline, or even a single bearing inside the gearbox. To fully understand the complete system it is necessary to investigate several or all parts simultaneously. This is especially true for transient (dynamic) simulation models with several interconnected parts. One solution for a more complete and accurate system analysis is to couple different simulation models into one coherent simulation, also called a co-simulation. This also allows existing simulation models to be reused and preserves the investment in these models. Existing co-simulation applications are often capable of interconnecting two specific simulators where a unique interface between these tools is defined. However, a more general solution is needed to make co-simulation modelling applicable for a wider range of tools. Any such solution must also be numerically stable and easy to use in order to be functional for a larger group of people. The presented approach for mechanical system co-simulations is based upon a general framework for co-simulation and meta-modelling [9]. Several tool specific simulation models can be integrated and connected by means of a meta-model. A platform independent, centralised, meta-model simulator is presented that executes and monitors the co-simulation. All simulation tools that participate in the co-simulation implement a single, well defined, external interface that is based on a numerically stable method for force/moment interaction.

It is often beneficial for an autonomous agent that operates in a complex environment to make use of different types of mathematical models to keep track of unobservable parts of the world or to perform prediction, planning and other types of reasoning. Since a model is always a simplification of something else, there always exists a tradeoff between the model’s accuracy and feasibility when it is used within a certain application due to the limited available computational resources. Currently, this tradeoff is to a large extent balanced by humans for model construction in general and for autonomous agents in particular. This thesis investigates different solutions where such agents are more responsible for balancing the tradeoff for models themselves in the context of interleaved task planning and plan execution. The necessary components for an autonomous agent that performs its abstractions and constructs planning models dynamically during task planning and execution are investigated and a method called DARE is developed that is a template for handling the possible situations that can occur such as the rise of unsuitable abstractions and need for dynamic construction of abstraction levels. Implementations of DARE are presented in two case studies where both a fully and partially observable stochastic domain are used, motivated by research with Unmanned Aircraft Systems. The case studies also demonstrate possible ways to perform dynamic abstraction and problem model construction in practice., Report code: LiU-Tek-Lic-2008:21.

The word and the concept of meta are used in virtually all disciplines of computing. Professionals often use it intuitively and in specific contexts in which the meaning of a word containing the meta- prefix is well understood, at least by specialists. For example, all experts in artificial intelligence know what metarules are and where they are useful. However, the meta can imply much more than understanding some concepts in a specific domain. This paper surveys some of the most interesting cases of using the concept of meta in computing in order to help build the big picture.

Many companies are trying to create useful toolboxes for their method application in business development work. The main problem here is to build fruitful links between different methods in use. This paper will show a framework for method combination using chains and alliances of established methods in the market. This framework for working with methods in concert is based on techniques for meta-modelling and method evaluation (Nilsson, 1999). The perspective taken is how a business manager can communicate with a systems expert by applying common methods. A business developer's toolbox consists of a general map of methods för strategic development, process development and systems development and how these methods could interact in a practical situation. The paper was presented at the following scientific conferences: 1. The Eleventh International Conference on Information Systems Development - ISD 2002, 12-14 September 2002, Riga Technical University (RTU), Latvia 2. The Second International Conference on Information Management Methodologies, 3-4 April 1998, Växjö University, Sweden

Many companies are trying to create useful toolboxes for their method application in business development work. The main problem here is to build fruitful links between different methods in use. This chapter will show a framework for method integration using chains and alliances of established methods in the market. The framework is based on some techniques for meta-modelling and method-evaluation. The perspective taken is how a business manager can communicate with a systems expert by applying common methods, Business modelling

Business managers and systems experts often experience frustration when information support for business activities is being discussed. A major part of the problem is due to lack of essential communication. Accusations from both sides is often the result: "The business people do not know what they want!" or "The systems people do not understand what we need!" However, communication is more than talking. It requires a firm base for common understanding, a common language. The main objective is to bridge the communication gap between business managers and systems experts through mutual use of each others methodologies for development work. The purpose of this research project is to investigate and analyze methodologies for business development and how they can be linked to common methodologies for information systems development. In this context we shall also study the effects of applying methodologies in differnet companies. The aim of the project is to produce practical guidelines for integrating business and systems development. The project plan was implemented as suggested in this research report and the Business Modelling project was doumented in the scientific and professional book from Springer Verlag: "Perspectives on Business Modelling" (Nilsson, A.G., Tolis, C., Nellborn, C.) from 1999

Constructing high-speed railway networks received a great attention during pastdecade raising new safety concerns on infrastructure (particularly bridges). It ismainly because of possible excessive vibrations due to higher operating speeds.In this regard, deficiency or vague scientific background for some of designmethodologies are shown by former studies; among which is the adopted safetyfactor for running safety. This limit state occurs if the load path from the trainto the bridge is disturbed by dislocating ballast particles because of excessivevertical accelerations of the bridge deck. Hence, the current article is devotedto update the conventional design methodology. For this objective, reliabilitybaseddesign optimization technique is employed to propose minimum allowablemass and stiffness (or maximum permissible fundamental frequency) which assuressatisfying target reliability level. This is achieved by adaptively trainingKriging meta-models to surrogate the computational models. It seems that theproposed method can result in lighter (economical) bridges in comparison tothe conventional design methodology; however, this beneficial aspect vanishesby increasing span length of the bridge., QC 20211027, Shift2Rail Joint Undertaking under the European Union’s Horizon 2020 research and innovation program, In2Track2