This paper provides a first-order structural feasibility assessment for a conceptual 150-meter class, robotically constructed optical space telescope. The greatest engineering challenges are assumed to reside in the d...
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ISBN:
(纸本)1563478927
This paper provides a first-order structural feasibility assessment for a conceptual 150-meter class, robotically constructed optical space telescope. The greatest engineering challenges are assumed to reside in the design and assembly of the 150-m diameter primary reflector. This study focuses on a structural analysis of that component, with technology developed for construction of the primary assumed to be applicable to the construction of all smaller optical structures (secondary, tertiary, etc.). A representative set of ground and onorbit loading constraints were evaluated using a "Hedgepeth-based" structural analysis approach to define and assess performance requirements of the primary reflector. Results of the surface precision analysis show that active adjustment of the primary structure is necessary to meet the stringent optical surface requirements. Two potential actuation strategies are discussed along with potential actuation devices extrapolated from the current state of the art. Distortions of the primary reflector backing truss structure due to thermal effects are also considered. Results from this analysis suggest that very tight tolerances on thermal gradients within the truss structural elements will be the most challenging engineering problem to overcome for constructing space telescope structures at this scale.
Plug and Play spacecraft offer the potential for simplified flight software development, rapid spacecraft assembly and integration, late addition of new components and technologies, and more automated testing and post...
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ISBN:
(纸本)1563478935
Plug and Play spacecraft offer the potential for simplified flight software development, rapid spacecraft assembly and integration, late addition of new components and technologies, and more automated testing and post-deployment flexibility. The Air Force Research Laboratory (AFRL) has established a program to develop standards for Space Plug and Play Avionics (SPA) that is based on commercial technologies, including USB. One of the outstanding issues in SPA is the development of a common data vocabulary that uniquely defines a finite set of spacecraft components and their structural and functional relationships. This common data vocabulary would form the core of an easy-to-use tool set that would assist non-experts in defining the bus and payload for rapid-response spacecraft. The common data vocabulary would also enable true Plug and Play functionality by automatically defining component interfaces above the physical networking layer. Recently, the NASA New Millennium program (NMP) and The Aerospace Corporation developed a spacecraft taxonomy and ontology database known as XCALIBR (XML Capability Analysis Library). This paper describes the potential application of the XCALIBR ontology and development process to the SPA common data vocabulary problem.
Future In-Space propulsion systems for exploration programs will invariably require data collection from a large number of sensors. Consider the sensors needed for monitoring several vehicle systems' states of hea...
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ISBN:
(纸本)1563478188
Future In-Space propulsion systems for exploration programs will invariably require data collection from a large number of sensors. Consider the sensors needed for monitoring several vehicle systems' states of health, including the collection of structural health data, over a large area. This would include the fuel tanks, habitat structure, and science containment of systems required for Lunar, Mars, or deep space exploration. Such a system would consist of several hundred or even thousands of sensors. Conventional avionics system design will require these sensors to be connected to a few Remote Health Units (RHU), which are connected to robust, micro flight computers through a serial bus. This results in a large mass of cabling and unacceptable weight. This paper first gives a survey of several techniques that may reduce the cabling mass for sensors. These techniques can be categorized into four classes: power line communication, serial sensor buses, compound serial buses, and wireless network. The power line communication approach uses the power line to carry both power and data, so that the conventional data lines can be eliminated. The serial sensor bus approach reduces most of the cabling by connecting all the sensors with a single (or redundant) serial bus. Many standard buses for industrial control and sensor buses can support several hundreds of nodes, however, have not been space qualified. Conventional avionics serial buses such as the Mil-Std-1553B bus and IEEE 1394a are space qualified but can support only a limited number of nodes. The third approach is to combine avionics buses to increase their addressability. The reliability, EMI/EMC, and flight qualification issues of wireless networks have to be addressed. Several wireless networks such as the IEEE 802.11 and Ultra Wide Band are surveyed in this paper. The placement of sensors can also affect cable mass. Excessive sensors increase the number of cables unnecessarily. Insufficient number of sensors m
This paper examines the relationship between retail land use and neighborhood satisfaction along with the moderating and mediating effects of trees and shrubs. Neighborhood satisfaction has been related to a number of...
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Aboard current ships, such as the DDG 51, engineering control and damage control activities are manpower intensive. It is anticipated that, for future combatants, the workload demand arising from operation of systems ...
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Aboard current ships, such as the DDG 51, engineering control and damage control activities are manpower intensive. It is anticipated that, for future combatants, the workload demand arising from operation of systems under conditions of normal steaming and during casualty response will need to be markedly reduced via automated monitoring, autonomous control, and other technology initiatives. Current DDG 51 class ships can be considered as a manpower baseline and under Condition III typical engineering control involves seven to eight watchstanders at manned stations in the Central Control Station, the engine rooms and other machinery spaces. In contrast to this manning level, initiatives such as DD 21 and the integrated engineering plant (IEP) envision a partnership between the operator and the automation system, with more and more of the operator's functions being shifted to the automation system as manning levels decrease. This paper describes some human systems integration studies of workload demand reduction and, consequently, manning reduction that can be achieved due to application of several advanced technology concepts. Advanced system concept studies in relation to workload demand are described and reviewed including. Piecemeal applications of diverse automation and remote control technology concepts to selected high driver tasks in current DDG 51 activities. development of the reduced ship's crew by virtual presence system that will provide automated monitoring and display to operators of machinery health, compartment conditions, and personnel health. The IEP envisions the machinery control system as a provider of resources that are used by various consumers around the ship. Resource needs and consumer priorities are at all times dependent upon the ship's current mission and the availability of equipment pawnbrokers.
作者:
Baker, CKrull, RSnyder, GLincoln, WMalone, TBClifford C. Baker
CIE CHFEP is a senior staff scientist at Carlow International Incorporated. He has applied most of his 24 years of experience in the application of human engineering technology to maritime systems. Mr. Baker has directed much of Carlow's efforts to reduce ship workload and to improve human performance and maritime safety through application of human factors methods and data. He is a Certified Industrial Ergonomist (CIE) as well as a Certified Human Factors Engineering Professional (CHFEP). Both certifications were granted by Oxford Research where Mr. Baker also serves as an Advisory Board member. Russell D. Krull
P.E. is a senior engineer with A&T/Proteus Engineering with more than 18 years of experi-ence in marine engineering naval architecture and program management including 16 years of active duty in the U.S. Coast Guard. Recent experience includes advanced ship design studies engineering software development technical support for the USMC Advanced Amphibious Assault Vehicle propulsion systems analyses ship structural engineering and cargo handling systems engineering. Mr. Krull has an M.S.E. in naval architecture and marine engineering and an M.S.E. in industrial and operations engineering from University of Michigan and a B.S. in ocean engineering from the U.S. Coast Guard Academy. Capt. Glenn L. Snyder
USCG. Regrettably since this paper was originally written Capt. Snyder has passed away. At the time of his death he was an operations specialist assigned to the Coast Guard's Deepwater Capabilities Replacement Project as Chief of Human Systems Integration. He served as commanding officer of the patrol boat Cape George (WPB-95306) the icebreaking tug Biscayne Bay (WTGB-104) and the cutter Legare (WMEC-911). A 1975 graduate of the U.S. Coast Guard Academy Capt. Snyder held an M.A. in national security and strategic studies from the U.S. Naval War College and an M.A. in international relations from Salve Regina College. In addition he was a 1998 fellow of the Foreign Service
The U.S. Coast Guard is in the concept exploration phase of its Integrated Deepwater System (IDS) acquisition project. This project will define the next generation of surface, air and command, control, communications,...
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The U.S. Coast Guard is in the concept exploration phase of its Integrated Deepwater System (IDS) acquisition project. This project will define the next generation of surface, air and command, control, communications, computers, intelligence, surveillance, and reconnaissance (C4ISR) assets used to perform the Coast Guard's missions in the IDS environment (>50 NM off the U. S. coastline). As part of early technology investigations, the needs exist to: (1) analyze the workload requirements of the IDS, (2) identify alternative means to perform ship's work, and (3) optimize ship manning consistent with ship workload, performance criteria, and the available tools and equipment aboard. To reduce shipboard work requires an understanding of the mission and support requirements placed on the vessel and crew, how these requirements are currently met, and how requirements might otherwise be met to reduce workload and crew size. This study examined currently implemented workload and manpower reducing approaches of commercial maritime fleets, U.S. and foreign navies, and foreign coastguards. These approaches were analyzed according to evaluation criteria approved by the IDS acquisition project team. From this, strategies for shipboard work reduction that may be considered for adoption by the IDS were identified and analyzed according to performance and costs factors. Ten workload-reducing strategies were identified: damage control, bridge, multiple crewing, engineering, risk acceptance, modularity, deck, enabling technologies, ship/personnel readiness, and operability and maintainability.
作者:
Kopack, DSmith, GKim, DErne, DLDavid F. Kopack:is a Program Manager in the Naval Sea Systems Command
Office of Environmenta1 Protection Occupational Safety and Health SEA 00T. Mr. Kopack received his bachelor and master of science degrees in the physical sciences and management from the University of Maryland. Mr. Kopack has 20 years of experience in ship design and engineering industrial facility operations and program management. Gordon D. Smith:is a Chemical Engineer with the Carderock Division Naval Surface Warfare Center in Bethesda
Maryland and is working in the Naval Sea Systems Command Environmental and Auxiliary Systems Group. SEA 03L. Mr. Smith received his bachelor of science degree in chemical engineering from The Ohio State University. He has over 13 years of ronmental issues. In addition to supporting the development of Uniform National Discharge Standards he has been involved in research design testing and development of pollution abatement technologies suitable for use aboard Navy Ships. Don K. Kim:is a Senior Mechanical Engineer with the naval architecture and marine engineering firm of M. Rosenblatt & Son
Inc. in Arlington Virginia. Mr. Kim received his bachelor of science and master of engineering degrees in mechanical engineering from the University of Virginia. He is a registered Professional Engineer in the Commonwealth of Virgina. Mr. Kim has ten years of experience in the design installation maintenance and repair of shipboard mechanical systems equipment and components with specific expertise in compressor pump and fan design and operation. He is a member of the American Society of Naval Engineers and the American Society of Mechanical Engineer. David L. Erne:is an Associate with Booz Allen and Hamilton
Inc. in Arlington Virginia. Mr. Erne received his bachelor of science degree in chemical engineering from the University of Idaho. He has over twelve years of experience in environmental program management and consulting. In addition to his support for the Uniform National Discharge Standards prog
In the Fiscal Year 1996 National Defense Authorization Act, Congress amended the Clean Water Act to provide the department of Defense and the Environmental Protection Agency authority to jointly establish standards fo...
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In the Fiscal Year 1996 National Defense Authorization Act, Congress amended the Clean Water Act to provide the department of Defense and the Environmental Protection Agency authority to jointly establish standards for incidental discharges from Armed Forces' vessels. The uniform national standards would apply to discharges from vessels of the Navy, Military Sealift Command, Army, Marine Corps, Air Force, and Coast Guard to the navigable waters and contiguous zone of the U.S. and its territories. Uniform National Discharge Standards (UNDS) will require control of discharges, by either a technology or management practice. UNDS will facilitate the Armed Forces' ability to better design and build future vessels to be environmentally sound and to maintain the operational flexibility of Armed Forces' vessels both domestically and internationally. The development of standards for Armed Forces' vessel discharges may have greater impact on naval engineering requirements for future vessels than any other single environmental issue, These standards are expected to stimulate the development of innovative vessel pollution control technologies, which on be used for both Armed Forces' vessels and commercial shipping vessels. This paper provides an overview of UNDS development, summarizes the results of UNDS Phase I, provides a summary overview of the preliminary approach for accomplishing UNDS Phase Il, and discusses implications for future naval engineering efforts.
In this paper, a methodology and guidelines for applying risk methods in design and operation of maritime systems were developed and demonstrated using a case study of marine diesel generators. The methodology consist...
In this paper, a methodology and guidelines for applying risk methods in design and operation of maritime systems were developed and demonstrated using a case study of marine diesel generators. The methodology consists of several modules that include system definition based on functional and performance requirements, definition of dependencies among subsystems, data collection and reduction, reliability and risk analyses, and results reduction for use in decision analysis. The methodology was used to assess and analyze typical service diesel generators found onboard ships. The analysis included the generation of cut sets for the overall reliability of the system. The most likely failure scenarios were determined by demonstration as the failure of fuel supply components. The results are consistent with previous findings of the U.S. Coast Guard.
作者:
Arntson, SLind, WTurner, JJBlaiklock, WCTedesco, MStephen G. Arntson is an independent consultant. A degree Naval Architect
he has over 38 years of experience in the design construction and maintenance of surface ships. His experience includes 28 yeus with the Naval Sea Systems Command Naval Ship Engineering Centerl Bureau of Ships specializing in the structural design of Naval surface ships and 7 years with ABS Specializing in the application of commercial ship design practices. Most recently he worked with both NASSCO and ABS MZ the Arsenal Ship Program. Steve was very active with the Ships Structure Committee in developing R&D programs for ship structure and he is a member of the ASNE Journal Committee. Steve received a BS in Mechanical Engineering (Naval Architecture Option) from Virginia Polytechnic Institute in 1964. He is a member of the ASNE TAU BETA PI PI TAU SIGMA and PHI KAPPA PHI. William 1. Lind joined ABS in 1992 after ten years with Sparkman and Stephens
Inc. He is currently ABS Amekas Manager of Engineering jm New Orleans and Cleveland. Both ofices conduct plan reviews for militavy commercial and private marine craft fm self-propelled vessels under 300 feet in length and bargus unlimited in length. As Vice-Chaimn ojthe Western Rivers Technical Committee Great Lakes Technical Committee and the Small Vessel Committee Bill participated in the writing of the 1997 ABS Guide for Building and Classing High Speed Craft and the 1997 ABS Rules for Building and Classing Steel Vessels Under 9OM. Bill received an MBA from Florida Atlantic University in 1995 a BS in Mechanical Engineering from New York Institute of Technology in 1986 and a BA in Histoy from Colgate University in 1976. He is Chaimn of SNAME HS-9 Composite Panel Testing & Fire Protection and a member of ASNE. John J. Turner is Senior Vice President of SYNTEK Technologies
Inc. in Arlington Virginia. SYNTEK specializes in activities of a highly technical nature supporting both industry and government in domestic and international markets. He is a registered Professional Engineer
The Defense Advanced Research Project Agency (DARPA), in conjunction with the U.S. Navy, initiated a research program for the design and construction of a distinctive warship for the 21st century known as the Arsenal ...
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The Defense Advanced Research Project Agency (DARPA), in conjunction with the U.S. Navy, initiated a research program for the design and construction of a distinctive warship for the 21st century known as the Arsenal Ship. By using an innovative development and acquisition approach it was hoped to streamline the procurement process and reduce costs. In an environment where budgets are being cut, both industry and Government were challenged to develop, design, and produce the innovative ship and related mission systems to meet specific performance capabilities within strict affordability constraints. A key element of this innovative acquisition approach was a new certification scheme designed to replace the traditional test and evaluation (T&E) and acceptance process. The purpose of this paper is to describe the development of the certification plan during Phase LI of the Arsenal Ship program by the American Bureau of Shipping and the contending Shipyard teams, and to discuss the potential benefits of this alternative certification approach. Although the Arsenal Ship program was canceled late in 1997, insight derived from the exploration of new certification concepts could benefit future design and building programs.
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