Decomposition theory is concerned with the structures that arise in the decomposition of systems. It states from the premise that any method of system decomposition is based, either explicitly or implicitly, on some c...
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Decomposition theory is concerned with the structures that arise in the decomposition of systems. It states from the premise that any method of system decomposition is based, either explicitly or implicitly, on some concept of dependence. The formal setting of decomposition theory is the dependence, an ordered-triple ( E , M , D ), where E is a nonempty set, M is a collection of subsets of E , and D is a relation from nonempty subsets of M to subsets of M . If ( A , B )∈ D , it is said that ` A depends on B '. Duality is considered here. In particular, given a dependence ( E , M , D ), its dual is a dependence ( E , M , D '). Duality plays a role here similar to duality in other formal systems such as graphs, matroids, lattices, circuits, control systems, and so forth. It deepens our understanding of dependence by pairing seemingly different concepts.
The potential use of rudders as anti-roll devices has long been recognized. However, the possible interference of this secondary function of the rudder with its primary role as the steering mechanism has prevented, fo...
The potential use of rudders as anti-roll devices has long been recognized. However, the possible interference of this secondary function of the rudder with its primary role as the steering mechanism has prevented, for many years, the development of practical rudder roll stabilizers. The practical feasibility of rudder roll stabilization has, however, in recent years been demonstrated by two systems designed and developed for operational evaluation aboard two different U.S. C oast G uard Cutters, i.e., Jarvis and Mellon of the 3,000-ton, 378-foot HAMILTON Class. The authors describe the major components of the rudder roll stabilization (RRS) system, along with the design goals and methodology as applied to these first two prototypes. In addition, a brief history of the hardware development is provided in order to show some of the lessons learned. The near flawless performance of the prototypes over the past four years of operational use in the North Pacific is documented. Results from various sea trials and reports of the ship operators are cited and discussed. The paper concludes with a discussion of the costs and benefits of roll stabilization achieved using both a modern anti-roll fin system, as well as two different performance level RRS systems. The benefits of roll stabilization are demonstrated by the relative expansion in the operational envelopes of the USS OLIVER HAZARD PERRY (FFG-7) Class. The varying levels of roll stabilization suggest that the merits of fins and RRS systems are strongly dependent on mission requirements and the environment. The demonstrated performance of the reliable RRS system offers the naval ship acquisition manager a good economical stabilization system.
The structural design of a ship's section is a complicated, repetitive and time consuming task. With the advent of new technology, high speed computers have enabled the ship designer to accomplish in a matter of s...
The structural design of a ship's section is a complicated, repetitive and time consuming task. With the advent of new technology, high speed computers have enabled the ship designer to accomplish in a matter of seconds what would formerly take days to accomplish by hand. The Structural Synthesis Design program (SSDP) is a N avy developed computer-aided design tool which is used to design (or to analyze) the longitudinal scantlings for a variety of ship cross sections, consisting of any practical combinations of decks, platforms, bulkheads and materials, i.e., various steel and aluminum alloys. The final hull section design will have the lowest practical weight for the chosen geometric configuration, structural arrangements, and imposed loadings. The scantling developed by the program will satisfy all U.S. N avy ship structural design criteria. An explanation of the objective and design elements of N avy ship structures is included. The rationale behind the SSDP design philosophy is developed along with the significant program capabilities. In an attempt to highlight the influence of automated design procedures on the current naval ship design process, the effect of the SSDP on the DDG 51 destroyer structural development is addressed.
Vehicle operating policies are developed and a longitudinal controller is designed to satisfy the stringent performance criteria of an Automated Guideway Transit (AGT) System operating under model-reference control. T...
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Vehicle operating policies are developed and a longitudinal controller is designed to satisfy the stringent performance criteria of an Automated Guideway Transit (AGT) System operating under model-reference control. The complete control system is comprised of two parts, a model generator and a vehicle controller. The generation of a model velocity, based on ideal vehicle kinematics which include jerk and acceleration limiting, is examined with respect to the performance criteria required for safe operation. Using the phase-plane follower spacing policy, a vehicle controller is designed, evaluated, and implemented on an 8-bit microprocessor to control the vehicle through various maneuvers as simulated on an analog computer.
One of the most serious problems encountered in Naval steam plants following World War II was the unreliable performance of boiler and main feedpump pneumatic control systems. In addition to control component and syst...
One of the most serious problems encountered in Naval steam plants following World War II was the unreliable performance of boiler and main feedpump pneumatic control systems. In addition to control component and system design deficiencies, these control systems suffered from inadequate methods to measure and adjust system alignment. This paper describes the development of a set of procedures for on-line alignment verification (OLV) of pneumatic main boiler and feedpump control systems. The procedures are designed for use by N avy control system technicians and, in addition to on-line alignment verification, provide guidance for troubleshooting and for performing system alignment. Procedure static checks measure steady state steaming performance and OLV procedure dynamic checks measure the ability of the boiler and control systems to respond to load changes. The paper describes typical control system characteristics that influence OLV procedure content and the supporting analysis that was used to establish alignment criteria ranges that satisfy both steady state and transient performance requirements. Also described is the alignment criteria tolerance analysis along with the steps involved in a typical OLV check procedure development. Descriptions of the various OLV checks, troubleshooting procedures and alignment procedures are provided. Typical shipboard implementation requirements are described and experience to date with the procedures is provided along with a status report on OLV procedure implementations.
作者:
FLUK, HThe authorgraduated from New York University in 1952 as an Aeronautical Engineer and entered the United States Air Force (USAF). He attended the USAF Institute of Technology for graduate Aerodynamics
and following that served three years as a Project Officer in the field of Special Weapons. Returning to civilian life in 1957 he joined Curtiss-Wright Corporation's Engine Division and shortly thereafter transferred to the company's Model 200 V/STOL Aircraft Program later to become the Tri-Service X-19. His responsibilities variously included Flight Loads and Controls Aerodynamic Research and publication of the X-19 Aircraft Technology. In 1966 he joined Boeing's VERTOL Division initially working in helicopter stability and then in downwash and autorotation characteristics. This was followed by research and development and long-range planning and then assignment to introduce new computer services to the Engineering Department. In 1975 he joined the Naval Air Engineering Center Lakehurst N.J. to provide technology in horizontal and vertical engine jet flows and at the present time is Manager for Systems Studies in the Advanced Systems Office where he works with the Aircraft and Ship Communities to enhance military effectiveness at sea.
A weapons system has been configured specifically to counter (or preempt) the long-range standoff missile threat. Rationale for this system starts with a discussion of cost and weight, and shows why modern multi-missi...
A weapons system has been configured specifically to counter (or preempt) the long-range standoff missile threat. Rationale for this system starts with a discussion of cost and weight, and shows why modern multi-mission systems have become intolerably expensive. Questions are raised regarding the advantages and disadvantages of building future naval aviation forces solely around the Aircraft Carrier Battle Group. The application of a few small modern ships, forming a future Battle Force, holds promise for large economies. Likewise, some accepted views regarding CTOL (Conventional Take Off & Laundry) and V/STOL (Vertical Short Take Off & Launding) aircraft are revisted in terms of their relative costs. A weapons system is proposed which, at one-fourth the weight of an Aircraft Carrier Battle Group, may be produced and operated for one-third the cost.
作者:
RESNER, MEKLOMPARENS, SHLYNCH, JPMr. Michael E. Resner:received an Engineering Degree from Texas A&M University in 1966 and has done graduate work in management at American University. He is Director
Machinery Arrangements/Control Systems and Industrial Facilities Division (SEA 525) at the Naval Sea Systems Command. His previous positions have included Program Manager Solar Total Energy Program at the Department of Energy and Branch Chief Machinery Control Systems Branch at the Naval Ship Engineering Center. Mr. Stephen H. Klomparens:is a Naval Architect at Designers & Planners
Inc. and is engaged in development of computer aids for ship design. He received his B.S.E. degree in Naval Architecture and Marine Engineering from the University of Michigan in 1973 and his M.S. degree in Computer Science from the Johns Hopkins University. Mr. Kolmparens began his professional career at Hydronautics Inc. in 1974 where he was involved in the use of marine laboratory facilities for test and development of conventional and advanced marine craft. Since 1977 he has been involved with naval and commercial ship design and with development of computer-aided ship design tools. Mr. John P. Lynch:is a Principal Marine Engineer with Hydronautics
Inc. He was previously employed in the auxiliary machinery and computer-aided design divisions of the David W. Taylor Naval Ship R&D Center the machinery design division of the New York Naval Shipyard and the machinery arrangement code of the Bureau of Ships. His active naval service was as a ship superintendent in the production department of the Long Beach Naval Shipyard. Mr. Lynch received his B. S. degree in Marine Engineering from the New York State Maritime College and his M.S. degree in Mechanical Engineering from Columbia University. He is a licensed Professional Engineer in the State of New York and a member of ASNE.
The machinery arrangement design process has remained relatively unchanged over the years. Recently, external demands have been placed on both the product and the producers that call for changes to this process. This ...
The machinery arrangement design process has remained relatively unchanged over the years. Recently, external demands have been placed on both the product and the producers that call for changes to this process. This paper cites these external demands and traces the evolution of the process changes from the rule-of-thumb machinery box sizing routines up to the current automated procedures. The machinery arrangement design practice is presented, and existing analytic and graphics aids are discussed. The user requirements for improved design aids are presented, with implementation guidelines and hardware/software alternatives.
Database management systems have evolved to the point of general acceptance and wide application;however a major problem still facmg the user is the effective utihzatlon of these systems. Important to achmving effecti...
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This paper discusses the Interactive Graphics System used by the General Electric Company, Medium Steam Turbine Department (engineering & Manufacturing) for designing, drafting, and manufacturing applications. A b...
This paper discusses the Interactive Graphics System used by the General Electric Company, Medium Steam Turbine Department (engineering & Manufacturing) for designing, drafting, and manufacturing applications. A brief overview of the hardware malting up the system is described, followed by a more detailed description of the actual applications. Two-dimensional applications described include a Heat Balance Analysis, Flow Diagrams, and Electrical Schematics. A more fruitful area for increased productivity gains is described in the three-dimensional or mechanical applications including turbine design & layout and bucket design. coordination of the design with manufacturing for numerical control tape generation is described through CAM and Plate Frame Cutting applications. Finally, a short review of the engineering design work using Interactive Graphics is discussed. Productivity gains of 2.6 to 1 are being realized, and the overall savings to the Medium Steam Department are outlined.
This paper presents an integrated approach to computer-Aided Ship Design for U.S. Navy preliminary and contract design. An integrated Hull Design System (HDS), currently under development by the Hull Group of the Nava...
This paper presents an integrated approach to computer-Aided Ship Design for U.S. Navy preliminary and contract design. An integrated Hull Design System (HDS), currently under development by the Hull Group of the Naval Sea Systems Command (NAVSEA 32). is the vehicle for the discussion. This paper is directed toward practicing ship design professionals and the managers of the ship design process. Primary emphasis of this paper, and of the development effort currently under way, is on aiding ship design professionals in their work. Focus is on integration and management control of the extremely complex set of processes which make up naval ship design. The terminology of the Ship Designer and Design Manager is used. The reader needs no familiarity with the technologies of computer science.
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