3,076 research outputs found

    MODELLING VIRTUAL ENVIRONMENT FOR ADVANCED NAVAL SIMULATION

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    This thesis proposes a new virtual simulation environment designed as element of an interoperable federation of simulator to support the investigation of complex scenarios over the Extended Maritime Framework (EMF). Extended Maritime Framework is six spaces environment (Underwater, Water surface, Ground, Air, Space, and Cyberspace) where parties involved in Joint Naval Operations act. The amount of unmanned vehicles involved in the simulation arise the importance of the Communication modelling, thus the relevance of Cyberspace. The research is applied to complex cases (one applied to deep waters and one to coast and littoral protection) as examples to validate this approach; these cases involve different kind of traditional assets (e.g. satellites, helicopters, ships, submarines, underwater sensor infrastructure, etc.) interact dynamically and collaborate with new autonomous systems (i.e. AUV, Gliders, USV and UAV). The use of virtual simulation is devoted to support validation of new concepts and investigation of collaborative engineering solutions by providing a virtual representation of the current situation; this approach support the creation of dynamic interoperable immersive framework that could support training for Man in the Loop, education and tactical decision introducing the Man on the Loop concepts. The research and development of the Autonomous Underwater Vehicles requires continuous testing so a time effective approach can result a very useful tool. In this context the simulation can be useful to better understand the behaviour of Unmanned Vehicles and to avoid useless experimentations and their costs finding problems before doing them. This research project proposes the creation of a virtual environment with the aim to see and understand a Joint Naval Scenario. The study will be focusing especially on the integration of Autonomous Systems with traditional assets; the proposed simulation deals especially with collaborative operation involving different types of Autonomous Underwater Vehicles (AUV), Unmanned Surface Vehicles (USV) and UAV (Unmanned Aerial Vehicle). The author develops an interoperable virtual simulation devoted to present the overall situation for supervision considering also the sensor capabilities, communications and mission effectiveness that results dependent of the different asset interaction over a complex heterogeneous network. The aim of this research is to develop a flexible virtual simulation solution as crucial element of an HLA federation able to address the complexity of Extended Maritime Framework (EMF). Indeed this new generation of marine interoperable simulation is a strategic advantage for investigating the problems related to the operational use of autonomous systems and to finding new ways to use them respect to different scenarios. The research deal with the creation of two scenarios, one related to military operations and another one on coastal and littoral protection where the virtual simulation propose the overall situation and allows to navigate into the virtual world considering the complex physics affecting movement, perception, interaction and communication. By this approach, it becomes evident the capability to identify, by experimental analysis within the virtual world, the new solutions in terms of engineering and technological configuration of the different systems and vehicles as well as new operational models and tactics to address the specific mission environment. The case of study is a maritime scenario with a representation of heterogeneous network frameworks that involves multiple vehicles both naval and aerial including AUVs, USVs, gliders, helicopter, ships, submarines, satellite, buoys and sensors. For the sake of clarity aerial communications will be represented divided from underwater ones. A connection point for the latter will be set on the keel line of surface vessels representing communication happening via acoustic modem. To represent limits in underwater communications, underwater signals have been considerably slowed down in order to have a more realistic comparison with aerial ones. A maximum communication distance is set, beyond which no communication can take place. To ensure interoperability the HLA Standard (IEEE 1516 evolved) is adopted to federate other simulators so to allow its extensibility for other case studies. Two different scenarios are modelled in 3D visualization: Open Water and Port Protection. The first one aims to simulate interactions between traditional assets in Extended Maritime Framework (EMF) such as satellite, navy ships, submarines, NATO Research Vessels (NRVs), helicopters, with new generation unmanned assets as AUV, Gliders, UAV, USV and the mutual advantage the subjects involved in the scenario can have; in other word, the increase in persistence, interoperability and efficacy. The second scenario models the behaviour of unmanned assets, an AUV and an USV, patrolling a harbour to find possible threats. This aims to develop an algorithm to lead patrolling path toward an optimum, guaranteeing a high probability of success in the safest way reducing human involvement in the scenario. End users of the simulation face a graphical 3D representation of the scenario where assets would be represented. He can moves in the scenario through a Free Camera in Graphic User Interface (GUI) configured to entitle users to move around the scene and observe the 3D sea scenario. In this way, players are able to move freely in the synthetic environment in order to choose the best perspective of the scene. The work is intended to provide a valid tool to evaluate the defencelessness of on-shore and offshore critical infrastructures that could includes the use of new technologies to take care of security best and preserve themselves against disasters both on economical and environmental ones

    Discovering the New Place of Learning

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    The book explores the potential of learning outside the traditional classroom when students gain real-world experiences in a variety of contexts and public spaces such as built, natural and virtual landscapes, museums, heritage sites, science centres and community venues. The authors of the book promote and put the flexible and ‘plastic’ concept of a place of learning into action by including physical geographical location, digital, virtual and textual spaces into the analysis. The book illuminates the importance of innovative educational strategies in connecting formal, non-formal and informal education – experiential learning in museums, heritage places and communities, inquiry-based pedagogy, digital storytelling, environmental online games, narrative geographies, and the use of geospatial technologies

    All-Electric Ship Design: From Electrical Propulsion to Integrated Electrical and Electronic Power Systems

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    Electrical propulsion is not a novel concept in marine systems. However, the availability of power electronic converters has proved to be the Key Enabling Technology for electrification of large ships. This paper starts with a summary of EP drives, which led to the birth of all-electric ships. Electric power generation and control systems are then presented, which make it possible to exploit the integrated electrical power system. To ease comprehension of the issues in designing such a system, its conventional design process is given. Then, the reasons that are pushing ahead the research in the shipboard power systems sector are discussed. The need for research in the design methods area is demonstrated through an overview of the latest results of technological research. Finally, a summary of the most significant results on the design tools research is given, including early stage design, dependable-oriented design, and the improvements achievable through software simulators and hardware-in-the-loop are discussed. The goal of this paper is to demonstrate why research on design methods is as important as a technological one, on the basis of the needs concerning the design, integration, and management of future 'integrated electrical and electronic power systems' (power systems with power conversion quota approaching 100%)

    Develop a Cyber Physical Security Platform for Supporting Security Countermeasure for Digital Energy System

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    The paper develops a cyber physical system (CPS) security platform for supporting security countermeasures for digital energy systems based on real-time simulators. The CPS platform provides functions that trainers or trainees can be able to operate and test their scenarios with a state-of-the-art integrated solution running at a real-time simulator. Those integrated solutions include energy systems simulation software and communication systems simulation/emulation software. The platform provides practical “hand-on-experiences” for participants and they are able to test, monitor and predict behaviors of both systems at the same time. The platform also helps achieve training’s objectives that meet skilled requirements for the future generation in both smart energy systems evaluation and cyber physical security fields. In particular, we present the CPS platform’s architecture and its functionalities. The developed CPS platform has also been validated and tested within different simulated threat cases and systems.©2022 Mike Mekkanen, Tero Vartiainen, Duong Dang. This work is licensed under a Creative Commons Attribution 4.0 International License.fi=vertaisarvioitu|en=peerReviewed

    The organization and management of nuclear power plants

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    The explanation of aggregate and sectoral investment behavior has been one of the less successful endeavors in empirical economics. Existing econometric models have had little success in explaining or predicting investment spending. This may be because most such models fail to account for the irreversibility of most investment spending. With irreversibility, changes in the riskiness of future cash flows or interest rates should in theory dramatically affect the decision to invest - more so than, say, a change in the levels of interest rates. Here I survey some of the empirical support for this proposition, and discuss the implications for investment modelling.Nuclear power plants are a controversial technology. The future of the industry depends on the ability to manage efficiently and safely, and to effectively manage organizational change as new technologies and practices are introduced and disseminated. This paper provides a conceptual framework and discussion of the management and organization of nuclear power plants around three questions: (1) How should nuclear power plants be organized and managed to ensure that they are operated most safely and efficiently? (2) What does an understanding of the organization and management of nuclear power plants tell us about how they change or resist change? and (3) What indicators or measures of various characteristics and processes of nuclear power plants are needed in order to address the above questions? We review existing literature on the organization and management of nuclear power plants, and suggest how we would structure a research project to address the above questions.Supported by the Center for Energy Policy Research at M.I.T

    The utilization of engine room simulators for freshmen and career personnel : training and assessment

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    Advanced laboratory testing methods using real-time simulation and hardware-in-the-loop techniques : a survey of smart grid international research facility network activities

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    The integration of smart grid technologies in interconnected power system networks presents multiple challenges for the power industry and the scientific community. To address these challenges, researchers are creating new methods for the validation of: control, interoperability, reliability of Internet of Things systems, distributed energy resources, modern power equipment for applications covering power system stability, operation, control, and cybersecurity. Novel methods for laboratory testing of electrical power systems incorporate novel simulation techniques spanning real-time simulation, Power Hardware-in-the-Loop, Controller Hardware-in-the-Loop, Power System-in-the-Loop, and co-simulation technologies. These methods directly support the acceleration of electrical systems and power electronics component research by validating technological solutions in high-fidelity environments. In this paper, members of the Survey of Smart Grid International Research Facility Network task on Advanced Laboratory Testing Methods present a review of methods, test procedures, studies, and experiences employing advanced laboratory techniques for validation of range of research and development prototypes and novel power system solutions
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