• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 7
  • 7
  • 2
  • 1
  • 1
  • Tagged with
  • 36
  • 36
  • 11
  • 8
  • 8
  • 7
  • 7
  • 5
  • 5
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Modeling of Distributed Naval Ship Systems using Architecture Flow Optimization

Robinson, Kevin Michael 06 July 2018 (has links)
Successful future surface combatants in the US Navy must embrace the growing integration and interdependency of propulsive and combat systems. Traditionally, the development of Hull, Mechanical and Electrical systems has been segregated from the development of weapons and sensors. However, with the incorporation of high energy weapons into future ship configurations, ship design processes must evolve to embrace the concept of a System of Systems being the only way to achieve affordable capability in our future fleets. This thesis bridges the gap between the physical architecture of components within a ship and the way in which they are logically connected to model the energy flow through a representative design and provide insight into sizing requirements of both system components and their connections using an Architecture Flow Optimization (AFO). This thesis presents a unique method and tool to optimize naval ship system logical and physical architecture considering necessary operational conditions and possible damage scenarios. The particular and unique contributions of this thesis are: 1) initially only energy flow is considered without explicit consideration of commodity flow (electric, mechanical, chilled water, etc.), which is calculated in post-processing; 2) AFO is applied to a large and complex naval surface combatant system of systems, demonstrating its scalability; 3) data necessary for the AFO is extracted directly from a naval ship synthesis model at a concept exploration level of detail demonstrating its value in early stage design; and 4) it uses network-based methods which make it adaptable to future knowledge-based network analysis methods and approaches. / Master of Science
22

Network-Based Naval Ship Distributed System Design using Architecture Flow Optimization

Parsons, Mark A. January 2019 (has links)
This thesis describes the application of a distributed system architecture framework and Architecture Flow Optimization (AFO) to naval ship Concept & Requirements Exploration (C&RE). It describes refinements to both C&RE and AFO, and naval surface combatant concept design case studies. The architectural framework decomposes naval ship distributed systems into the physical, logical, and operational architectures representing the spatial, functional, and temporal relationships of distributed systems respectively. This decomposition greatly simplifies the Mission, Power, and Energy System (MPES) design process for use in C&RE. AFO is a network-based linear programming optimization method used to design and analyze MPES at a sufficient level of detail to understand system energy flow, define MPES architecture and sizing, reduce system vulnerability and improve system reliability. AFO incorporates system topologies, energy coefficient component models, preliminary arrangements, and (nominal and damaged) steady state scenarios to minimize the energy flow cost required to satisfy all operational scenario demands and constraints. This thesis provides an overview of design tools developed to implement this process and methods, including objective attribute metrics for cost, effectiveness and risk, ship synthesis model, hullform exploration and MPES explorations using design of experiments (DOEs) and response surface models. / M.S. / The design of modern warships presents many unique challenges not faced in the design of most commercial ships or past generations of warships. The objectives of warship design (e.g. effectiveness, design risk, and total lifecycle cost) cannot be summarized in a single quantitative metric as commonly done in commercial ship design (e.g. required freight rate: the minimum market price of a commodity to make a commercial ship design with a certain cargo capacity profitable). Furthermore, misison, power, and energy systems (MPES) of modern warships have become increasingly interdependent and complex, especially those of naval surface combatants (non-submarine warships designed to engage in direct combat with other ships). Determining quantitative metrics for these objectives is a difficult task to begin with. Determining accurate values for these metrics in early stage design (when designs have little detailed specifications and some technologies may even be still be in development) is another challenge altogether. This thesis describes simple and robust methods and processes to evaluate a warship’s arrangement and operational characteristics. Survivability characteristics, characteristics related to a warship’s ability to complete missions despite battle damage, are of particular interest in these methods. These methods incorporate physics and energy-based means of assessment rather than using historical parametric models that are insufficient in assessing new and revolutionary warship designs.
23

"SEA ARCHER" Distributed Aviation Platform

Keller, Joe, Ivey, James, Dalakos, Antonios, Okan, Orhan, Kuchler, Ryan, Cooke, Rabon, Stallings, Brad, Searles, Scot, Gokee, Mersin, Lashomb, Pete, Byers, David, Papoulias, Fotis, Ciezki, John, Ng, Ivan 12 1900 (has links)
Includes supplemental material. / This report outlines the results of a two quarter Total Ship Systems Engineering (TSSE) Capstone design project undertaken by the students at the Naval Postgraduate School. The project was under the direction of Professors C.N. Calvano and R.Harney. / Currently, no system exists that provides a sea-based distributed aviation platform capability. The emergence of Unmanned Air Vehicles (UAVs) / Unmanned Combat Air Vehicles (UCAVs), the continued U.S. Navy focus on the littorals, the desire for force distribution, the need for operational cost reductions, and the advent of Network Centric Warfare (NCW) all continue to support the requirement to re-evaluate how littoral operations will be conducted in the future. Given this background, a bottom-up design of a ship supporting a primarily UAV/UCAV air wing in a low to medium threat environment is of significant interest. SEA ARCHER meets this interest. This report outlines a design that meets the future needs for distributed aviation with a high-speed, highly automated platform. Large gains in reduced manning through automated systems for both operation and damage control helpmeet the demanding needs for the future of the Navy at reduced operational costs. The report will outline both the Mission Needs Statement (MNS) and Operational Requirements Document (ORD) for the ship that was developed. The analysis of alternatives that was conducted to determine relative size requirements for the ship in presented in the next section. The concept design that resulted as a result of the Total Ship Systems Engineeing process in then presented. Finally, a detailed look at the analysis and trade studies that were conducted in presented in order to show the more detailed analysis that was conducted in designing the ship.
24

Innovation in Ship Design

McKesson, Christopher B 17 May 2013 (has links)
What is innovation in ship design? Is it a capability that is inherent in all naval architects? Is it the result of the application of a certain set of tools, or of operation within a certain organizational structure? Can innovation be taught? Innovation is a creative act that results in a new and game-changing product. The emergence of an innovative product creates an asymmetric market. The emergence of an innovative weapon creates an asymmetric battlefield. It is clearly in the economic and military interest of the United States to be able to develop and deploy innovative products, including innovative ships. But the process of ship design is usually one of incremental development and slow evolution. Engineers are taught to develop their product by paying close attention to previous developments. This approach is viewed by some people as anti-innovative. And yet the author has made a career of innovation in ship design. How has this been possible? This dissertation will answer the four questions posed above. It will show what innovation in ship design is, and where innovative naval architecture lies in the taxonomy of human creative endeavor. It will then describe those human attributes which have been found to be essential to successful innovation. It will also describe some of the many tools that innovators use. Some of those tools are used unconsciously. Some of those tools are formal products supported by research institutes and teaching academies. Finally, given the fact that innovation in ship design is a component of engineering – which is a subject taught in Universities – and that it is facilitated by the use of tools – and tool use can be taught – the author will conclude that innovation itself can be taught. Whether it can be mastered will depend upon the individual, just as with most other creative skills.
25

Architecture Flow Optimization - Refinement and Application for Naval Ship Concept Design

Bonsall, Jaxson Todd 31 May 2024 (has links)
This thesis describes the refinement of an Architecture Flow Optimization (AFO) tool for naval surface ship design, specifically focusing on the development of new network and matrix-based methods for AFO formulation and their application in Concept Development. The AFO tool analyzes and optimizes the flow of energy through the ship's Vital Components (VCs) interfacing with a Ship Synthesis and Product Model (SSM), ensuring that all physical and operational constraints are satisfied while minimizing system cost across multiple intact and damaged operational scenarios. The total ship system is described by physical and logical architectures in a network structure comprised of vital component nodes and arcs. These elements form the basis of a linear system of equations in matrix form, the manipulation of which relies heavily on linear algebra and matrix operations. The matrix system of equations is solved using linear programming with a significant improvement in computational efficiency. The solution supports the sizing of individual vital components and the refinement of system logical architecture. It also provides the basic AFO engine necessary to support future refinement of a dynamic architecture flow optimization (DAFO) with the computational speed necessary for rapid solution of dynamic mission scenarios insuring optimized and feasible warfighting reconfiguration, with and without damage. / Master of Science / This thesis describes the refinement of an Architecture Flow Optimization (AFO) tool for naval surface ship design, specifically focusing on the development of new network and matrix-based methods for AFO formulation and their application in naval ship Concept Development processes. The Architecture Flow Optimization tool analyzes and optimizes the flow of energy through the ship's Vital Components (VCs). The AFO tool completes this task by interfacing with a Ship Synthesis and Product Model (SSM), ensuring that all of the ship's physical and operational constraints are satisfied. This is done while minimizing the ship system cost across multiple intact and damaged operational scenarios. The total ship system is described by physical and logical architectures in a network structure comprised of vital components (nodes) and their connections (arcs). These elements form the basis of a linear system of equations in matrix form, the manipulation of which relies heavily on linear algebra and matrix operations. The matrix system of equations is solved using a linear programming algorithm with a significant improvement in computational speed. The solution provided from the optimization supports the sizing of individual vital components and the refinement of the ship system logical architecture. It also provides the basic AFO engine necessary to support future refinement of a dynamic architecture flow optimization (DAFO) with the computational speed necessary for rapid solution of dynamic mission scenarios insuring optimized and feasible warfighting reconfiguration, with and without damage.
26

Development and Application of Dynamic Architecture Flow Optimization to Assess the Impact of Energy Storage on Naval Ship Mission Effectiveness, System Vulnerability and Recoverability

Kara, Mustafa Yasin 20 May 2022 (has links)
This dissertation presents the development and application of a naval ship distributed system architecture framework, Architecture Flow Optimization (AFO), Dynamic Architecture Flow Optimization (DAFO), and Energy Storage System (ESS) model in naval ship Concept and Requirements Exploration (CandRE). The particular objective of this dissertation is to determine and assess Energy Storage System (ESS) capacity, charging and discharging capabilities in a complex naval ship system of systems to minimize vulnerability and maximize recoverability and effectiveness. The architecture framework is implemented through integrated Ship Behavior Interaction Models (SBIMs) that include the following: Warfighting Model (WM), Ship Operational Model (OM), Capability Model (CM), and Dynamic Architecture Flow Optimization (DAFO). These models provide a critical interface between logical, physical, and operational architectures, quantifying warfighting and propulsion capabilities through system measures of performance at specific capability nodes. This decomposition greatly simplifies the Mission, Power, and Energy System (MPES) design process for use in CandRE. AFO and DAFO are network-based, linear programming optimization methods used to design and analyze MPESs at a sufficient level of detail to understand system energy flow, define MPES architecture and sizing, model operations, reduce system vulnerability and improve system effectiveness and recoverability with ESS capabilities. AFO incorporates system topologies, energy coefficient component models, preliminary arrangements, and (nominal and damaged) steady state scenarios to minimize the energy flow cost required to satisfy all operational scenario demands and constraints. The refined DAFO applies the same principles as AFO, but adds two more capabilities, Propulsion and ESS charging, and maximizes effectiveness at each scenario timestep. DAFO also integrates with a warfighting model, operational model, and capabilities model that quantify the performance of tasks enabled by capabilities through system measures of performance at specific capability nodes. This dissertation provides a description of the design tools developed to implement these processes and methods, including a ship synthesis model, hullform exploration, MPES explorations and objective attribute metrics for cost, effectiveness and risk, using design of experiments (DOEs) response surface models (RSMs) and Energy Storage System (ESS) applications. / Doctor of Philosophy / This dissertation presents the development and application of a naval ship distributed system architecture framework, Architecture Flow Optimization (AFO), Dynamic Architecture Flow Optimization (DAFO), and Energy Storage System (ESS) design in naval ship Concept and Requirements Exploration (CandRE). The particular objective of this dissertation is to determine and assess Energy Storage System (ESS) capacity, charging and discharging capabilities in a complex naval ship system of systems to minimize vulnerability and maximize recoverability and effectiveness. The architecture framework is implemented through integrated Ship Behavior Interaction Models (SBIMs) that include the following: Warfighting Model (WM), Ship Operational Model (OM), Capability Model (CM), and Dynamic Architecture Flow Optimization (DAFO). These models provide a critical interface between logical, physical, and operational architectures, quantifying warfighting and propulsion capabilities through system measures of performance at specific capability nodes. This decomposition greatly simplifies the Mission, Power, and Energy System (MPES) design process for use in CandRE. AFO and DAFO are network-based, linear programming optimization methods used to design and analyze MPESs at a sufficient level of detail to understand system energy flow, define MPES architecture and sizing, model operations, reduce system vulnerability and improve system effectiveness and recoverability with ESS capabilities. AFO incorporates system topologies, energy coefficient component models, preliminary arrangements, and (nominal and damaged) steady state scenarios to minimize the energy flow cost required to satisfy all operational scenario demands and constraints. DAFO applies the same principles as AFO, but adds two more capabilities, Propulsion and ESS charging, and maximizes effectiveness at each scenario timestep. DAFO also integrates with a warfighting model, operational model, and capabilities model that quantify the performance of tasks enabled by capabilities through system measures of performance at specific capability nodes. This dissertation provides an overview of the design tools developed to implement these process and methods, including a ship synthesis model, hullform exploration, MPES explorations and objective attribute metrics for cost, effectiveness and risk, using design of experiments (DOEs) response surface models (RSMs) and Energy Storage System (ESS) applications.
27

Refinement of Surface Combatant Ship Synthesis Model for Network-Based System Design

Stinson, Nicholas Taylor 17 June 2019 (has links)
This thesis describes an adaptable component level machinery system weight and size estimation tool used in the context of a ship distributed system architecture framework and ship synthesis model for naval ship concept design. The system architecture framework decomposes the system of systems into three intersecting architectures: physical, logical, and operational to describe the spatial and functional relationships of the system together with their temporal behavior characteristics. Following an Architecture Flow Optimization (AFO), or energy flow analysis based on this framework, vital components are sized based on their energy flow requirements for application in the ship synthesis model (SSM). Previously, components were sized manually or parametrically. This was not workable for assessing many designs in concept exploration and outdated parametric models based on historical data were not sufficiently applicable to new ship designs. The new methodology presented in this thesis uses the energy flow analysis, baseline component data, and physical limitations to individually calculate sizes and weights for each vital component in a ship power and energy system. The methodology allows for new technologies to be quickly and accurately implemented to assess their overall impact on the design. The optimized flow analysis combined with the component level data creates a higher fidelity design that can be analyzed to assess the impact of various systems and operational cases on the overall design. This thesis describes the SSM, discusses the AFO's contribution, and provides background on the component sizing methodology including the underlying theory, baseline data, energy conversion, and physical assumptions. / Master of Science / This thesis describes an adaptable component level machinery system weight and size estimation tool used in the context of a preliminary ship system design and naval ship concept design. The system design decomposes the system of systems into three intersecting areas: physical, logical, and operational to describe the spatial and functional relationships of the system together with their time dependent behavior characteristics. Following an Architecture Flow Optimization (AFO), or energy flow analysis based on this system design, vital components are sized based on their energy flow requirements for application in the ship synthesis model (SSM). Previously, components were sized manually or with estimated equations. This was not workable for assessing many designs in concept exploration and outdated equation models based on historical data were not sufficiently applicable to new ship designs. The new methodology presented in this thesis uses the energy flow analysis, baseline component data, and physical limitations to individually calculate sizes and weights for each vital component in a ship power and energy system. The methodology allows for new technologies to be quickly and accurately implemented to assess their overall impact on the design. The optimized flow analysis combined with the component level data creates a more accurate design that can be analyzed to assess the impact of various systems and operational cases on the overall design. This thesis describes the SSM, discusses the AFO’s contribution, and provides background on the component sizing methodology including the underlying theory, baseline data, energy conversion, and physical assumptions.
28

Naval Ship Design and Synthesis Model Architecture Using a Model-Based Systems Engineering Approach

Kerns, Corey Michael 26 May 2011 (has links)
The Concept and Requirements Exploration process used at Virginia Tech is based on a Multi-Objective Optimization approach that explores the design space to produce a Non-Dominated set of ship design solutions ranked objectively by Cost, Risk, and Effectiveness. Prior research and effort has also been made to leverage the validation and verification of the U.S. Navy's ship synthesis design tool, ASSET, into the Virginia Tech Ship Synthesis Model. This thesis applies Design Structure Matrix theory to analyze and optimize the ASSET synthesis process by reducing or removing the feedback dependencies that require the iterative convergence process. This optimized ASSET synthesis process is used as the basis to develop a new Simplified Ship Synthesis Model (SSSM) using Commercial Off-The-Shelf (COTS) software, ASSET Response Surface Models (RSMs) and simplified parametric equations to build the individual synthesis modules. The current method of calculating an Overall Measure of Effectiveness (OMOE) used at Virginia Tech is based on expert opinion and pairwise comparison. This thesis researches methods for building a Design Reference Mission (DRM) composed of multiple operational situations (OpSits) required by the ship's mission. The DRM is defined using a Model Based Systems Engineering (MBSE) approach and an overall Ship Design System Architecture to define and understand the relationships between various aspects of the ship design. The system architecture includes the DRM and enables the development of Operational Effectiveness Models (OEMs) as an alternative to an expert opinion-based OMOE. The system architecture also provides the means for redefining and optimizing the entire ship design process by capturing the entire process and all related data into a single repository. This thesis concludes with a preliminary assessment of the utility of these various system engineering tools to the naval ship design process. / Master of Science
29

Development of a Quantitative Methodology to Forecast Naval Warship Propulsion Architectures

Waller, Brian S 15 May 2015 (has links)
This paper is an investigation into a quantitative selection process of either a mechanical or electrical system architecture for the transmission of propulsion power in naval combatant vessels. A database of historical naval ship characteristics was statistically analyzed to determine if there were any predominant ship parameters that could be used to predict whether a ship should be designed with a mechanical power transmission system or an electric one. A Principal Component Analysis was performed to determine the minimum number of dimensions required to define the relationship between the propulsion transmission architecture and the independent variables. Combining the results of the statistical analysis and the PCA, neural networks were trained and tested to separately predict the transmission architecture or the installed electrical generation capacity of a given class of naval combatant.
30

Sea TENTACLE: Track, Engage, & Neutralize Threats - Asymmetric & Conventional - in the Littoral Environment

Black, Brian C., Bollock, Laura H., Bouabid, Sinene, Glova, Michael A., Hall, Jason A., Harden, Glynn M., Hickle, Curtis J., Hosoglu, Selcuk, Majewicz, Peter, Mullenix, Kenneth R., Nozik, Andrew B., Sarar, Stephen F., Ucar, Hakan 01 1900 (has links)
Includes supplementary material. / Sea TENTACLE is a proposed afloat platform whose primary mission is to utilize the state-of-the-art technology of unmanned vehicles to monitor and neutralize all subsurface enemy threats in the littorals. This mission can be specified further as anti-submarine warfare, mine warfare and maritime surveillance. The design philosophy of Sea TENTACLE embodies the ideal of providing a multi-mission capable sea frame extending network-centric warfare into the littorals. The design goals of the TSSE team were first to develop a platform to deploy, recover, and maintain unmanned vehicle (e.g. UUVs, USVs, UAVs) and second to enableto ship to act as an afloat network operations center for distributed assets. Allowing all units to work together seamlessly to conduct focused missions in the littorals makes the Sea TENTACLE a creitical component within the network-centric environment. The versatility of its cargo hold and modular design allows Sea TENTACLE to be outfitted dynamically to complete a veriety of secondary missions including humanitarian aid, salvage and spacial operations support. Sea TENTACLE's combat management and operations system will employ the Enterprise architecture design enabling C4ISR capabilities that will meet emerging network centric warfare needs.

Page generated in 0.0377 seconds