1,458 research outputs found

    Model-Based Systems Engineering Approach to Distributed and Hybrid Simulation Systems

    Get PDF
    INCOSE defines Model-Based Systems Engineering (MBSE) as the formalized application of modeling to support system requirements, design, analysis, verification, and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases. One very important development is the utilization of MBSE to develop distributed and hybrid (discrete-continuous) simulation modeling systems. MBSE can help to describe the systems to be modeled and help make the right decisions and partitions to tame complexity. The ability to embrace conceptual modeling and interoperability techniques during systems specification and design presents a great advantage in distributed and hybrid simulation systems development efforts. Our research is aimed at the definition of a methodological framework that uses MBSE languages, methods and tools for the development of these simulation systems. A model-based composition approach is defined at the initial steps to identify distributed systems interoperability requirements and hybrid simulation systems characteristics. Guidelines are developed to adopt simulation interoperability standards and conceptual modeling techniques using MBSE methods and tools. Domain specific system complexity and behavior can be captured with model-based approaches during the system architecture and functional design requirements definition. MBSE can allow simulation engineers to formally model different aspects of a problem ranging from architectures to corresponding behavioral analysis, to functional decompositions and user requirements (Jobe, 2008)

    A collaborative platform for integrating and optimising Computational Fluid Dynamics analysis requests

    Get PDF
    A Virtual Integration Platform (VIP) is described which provides support for the integration of Computer-Aided Design (CAD) and Computational Fluid Dynamics (CFD) analysis tools into an environment that supports the use of these tools in a distributed collaborative manner. The VIP has evolved through previous EU research conducted within the VRShips-ROPAX 2000 (VRShips) project and the current version discussed here was developed predominantly within the VIRTUE project but also within the SAFEDOR project. The VIP is described with respect to the support it provides to designers and analysts in coordinating and optimising CFD analysis requests. Two case studies are provided that illustrate the application of the VIP within HSVA: the use of a panel code for the evaluation of geometry variations in order to improve propeller efficiency; and, the use of a dedicated maritime RANS code (FreSCo) to improve the wake distribution for the VIRTUE tanker. A discussion is included detailing the background, application and results from the use of the VIP within these two case studies as well as how the platform was of benefit during the development and a consideration of how it can benefit HSVA in the future

    Virtue integrated platform : holistic support for distributed ship hydrodynamic design

    Get PDF
    Ship hydrodynamic design today is often still done in a sequential approach. Tools used for the different aspects of CFD (Computational Fluid Dynamics) simulation (e.g. wave resistance, cavitation, seakeeping, and manoeuvring), and even for the different levels of detail within a single aspect, are often poorly integrated. VIRTUE (the VIRtual Tank Utility in Europe) project has the objective to develop a platform that will enable various distributed CFD and design applications to be integrated so that they may operate in a unified and holistic manner. This paper presents an overview of the VIRTUE Integrated Platform (VIP), e.g. research background, objectives, current work, user requirements, system architecture, its implementation, evaluation, and current development and future work

    Towards Managing and Understanding the Risk of Underwater Terrorism

    Get PDF
    This dissertation proposes a methodology to manage and understand the risk of underwater terrorism to critical infrastructures utilizing the parameters of the risk equation. Current methods frequently rely on statistical methods, which suffer from a lack of appropriate historical data to produce distributions and do not integrate epistemic uncertainty. Other methods rely on locating subject matter experts who can provide judgment and then undertaking an associated validation of these judgments. Using experimentation, data from unclassified successful, or near successful, underwater attacks are analyzed and instantiated as a network graph with the key characteristics of the risk of terrorism represented as nodes and the relationship between the key characteristics forming the edges. The values of the key characteristics, instantiated as the length of the edges, are defaulted to absolute uncertainty, the state where there is no information for, or against, a particular causal factor. To facilitate obtaining the value of the nodes, the Malice spectrum is formally defined which provides a dimensionless, methodology independent model to determine the value of any given parameter. The methodology produces a meta-model constructed from the relationships between the parameters of the risk equation, which determines a relative risk value

    A TOSCA-Based Conceptual Architecture to Support the Federation of Heterogeneous MSaaS Infrastructures †

    Get PDF
    Modeling and simulation (M&S) techniques are effectively used in many application domains to support various operational tasks ranging from system analyses to innovative training activities. Any (M&S) effort might strongly benefit from the adoption of service orientation and cloud computing to ease the development and provision of M&S applications. Such an emerging paradigm is commonly referred to as M&S-as-a-Service (MSaaS). The need for orchestrating M&S services provided by different partners in a heterogeneous cloud infrastructure introduces new challenges. In this respect, the adoption of an effective architectural approach might significantly help the design and development of MSaaS infrastructure implementations that cooperate in a federated environment. In this context, this work introduces a MSaaS reference architecture (RA) that aims to investigate innovative approaches to ease the building of inter-cloud MSaaS applications. Moreover, this work presents ArTIC-MS, a conceptual architecture that refines the proposed RA for introducing the TOSCA (topology and orchestration specification for cloud applications) standard. ArTIC-MS’s main objective is to enable effective portability and interoperability among M&S services provided by different partners in heterogeneous federations of cloud-based MSaaS infrastructure. To show the validity of the proposed architectural approach, the results of concrete experimentation are provided

    Development of Mobile Cloud Applications using UML

    Get PDF
    With the proliferation of cloud computing technologies, smartphone users are able to use a variety of cloud computing-based mobile services such as games, education, entertainment, and social networking. Despite the popularity of such a mobile cloud computing, the complicated multi-tier system configuration of the mobile application must be one of the major impediments to develop mobile cloud applications. This paper presents development processes and procedures for developing mobile cloud applications by effectively applying Unified Modeling Language (UML), a representative object-oriented modeling language. The paper is intended to enhance the development productivity of the mobile cloud application and to improve the effectiveness of communication between software developers. In addition, we used the Android mobile platform and Amazon Web Service for cloud computing in order to demonstrate the applicability of the proposed approach to systematically apply the UML profiles and diagrams for cloud-based mobile applications

    Ad hoc HLA simulation model derived from a model-based traffic scenario

    Get PDF
    Modern highly automated and autonomous traffic systems and sub-systems require new approaches to test their functional safety in the context of validation and verification. One approach that has taken a leading role in current research is scenario-based testing. For various reasons, simulation is considered to be the most practicable solution for a wide range of test scenarios. However, this is where many existing simulation systems in research reach their limits. In order to be able to integrate the widest possible range of systems to be tested into the simulation, the use of co-simulation has proven to be particularly useful. In this work, the High-Level Architecture defined in the IEEE 1516-2010 standard is specifically addressed, and a concept is developed that establishes the foundation for the feasible use of scenario-based distributed co-simulation on its basis. The main challenge identified and addressed is the resolution of the double-sided dependency between scenario and simulation models. The solution was to fully automate the generation and instantiation of the simulation environment on the basis of a scenario instance. Finally, the developed concept was implemented as a prototype, and the resulting process for its use is presented here using an example scenario. Based on the experience gained during the creation of the concept and the prototype, the next steps for future work are outlined in conclusion

    Application of Executable Architecture in Early Concept Evaluation using the DoD Architecture Framework

    Get PDF
    The increasing complexity in the development of today\u27s modern warfighting systems demands a systematic evaluation approach in the assessment of the envisaged capability and estimating the cost effectiveness, especially in the early stages of Concept Development. This research focused on the development of early Concept evaluation methodology through the use of Executable Architecture (EA) through the System Architecting process. Particularly, the methodology was applied in the assessment of a proposed Multi-tiered Unmanned Aircraft System System-of-System that is designed provide target acquisition and conduct dynamic strike on Theater Ballistic Missile launchers. Through the implementation of the evaluation methodology using dynamic modeling of the system-under-design, the research was able to provide quantitative assessment of different design parameters on the overall system effectiveness, as measured using a set of pre-determined Measures-of-Effectiveness. Specifically, Innoslate was used to develop the EA model of a fictitious multi-tier Unmanned Aircraft System System-of-Systems, and provided quantitative assessment of the overall system performance due to changes in the design parameters. Specification, the research showed that the proposed evaluation methodology provides system architects with the tool to 1) evaluate different design parameters, 2) understand the overall system capability given sub-system capabilities, and 3) determine sub-system requirement given desired system performance

    Data and knowledge manangement in field studies A case for semantic technologies

    Get PDF
    Ship design is a knowledge-intensive industry. To design safe ship systems for demanding operations, there is an increasing need for comprehensive knowledge of the operational context. Field studies is an important source of relevant knowledge, but current methods and information systems do not realise their full potential. In this paper, we discuss how the field data can be modelled semantically, integrated with relevant domain models, and be more effectively made available to the organisation. We propose a data model and a software architecture to facilitate the collaborative data analysis and modelling process favoured by designers
    • …
    corecore