Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moist...
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Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moisture resistance, and flammability and toxicity as well as cost and availability of thermoset and thermoplastic composite materials are presented. Methods for testing and reducing the flammability and toxicity are discussed. Many commercially available composite systems are reported to provide favorable characteristics for marine applications. Although there seems to be a need for improved production technology for thermoplastics, they present potential advantages in physical properties over thermoset composites.
作者:
BARROWS, LROCCHIO, JELarry Barrows received his M.S. and Ph.D. degrees in geophysics from the Colorado School of Mines in 1973 and 1978
respectively. He has worked as a systems engineer on Skylab remote-sensing experiments and as an exploration geophysicist in frontier areas of Alaska. Since 1979 he has specialized in geophysical surveying for ground water and hazardous waste site investigations first as the project geophysicist on a radioactive waste disposal program and then as a research scientist for the U.S. EPA. In 1988 he joined Earth Science and Engineering Inc. and LaCoste and Romberg Gravity Meters Inc. (4807 Spicewood Springs Rd. Bldg. 2 Austin TX 78759). Current projects include using microgravity to detect solution conduits in karst terrains and using seismicgroundroll to determine near-surface shear moduli. Judith E. Rocchio is the future air resource specialist on the Stanislaus National Forest (1977 Greenley Rd.
Sonora CA 95370). She will obtain the position upon completion of her M.A. degree in air resource management at Colorado State University Department of Natural Resources (1990). She was with Lockheed Engineering Management Services Co. Las Vegas Nevada prior to attending CSU where she was involved in several environmental monitoring programs and coauthored the paper with Dr. Barrows. From 1981 to 1986 Rocchio was a project geologist for Gower Oil Co. and Consolidation Coal Co. Denver Colorado. She received her B.S. in geology (1981) from the University of Nevada Las Vegas.
Field tests were conducted to determine representative total-intensity magnetic anomalies due to the presence of underground storage tanks and 55-gallon steel drums. Three different drums were suspended from a non-mag...
Field tests were conducted to determine representative total-intensity magnetic anomalies due to the presence of underground storage tanks and 55-gallon steel drums. Three different drums were suspended from a non-magnetic tripod and the underlying field surveyed with each drum in an upright and a flipped plus rotated orientation. At drum-to-sensor separations of 11 feet, the anomalies had peak values of around 50 gammas and half-widths about equal to the drum-to-sensor separation. Remanent and induced magnetizations were comparable; crushing one of the drums significantly reduced both. A profile over a single underground storage tank had a 1000-gamma anomaly, which was similar to the modeled anomaly due to an infinitely long cylinder horizontally magnetized perpendicular to its axis. A profile over two adjacent tanks had a smooth 350-gamma single-peak anomaly even though models of two tanks produceddual-peaked anomalies. demagnetization could explain why crushing a drum reduced its induced magnetization and why two adjacent tanks produced a single-peak anomaly. A 40-acre abandoned landfill was surveyed on a 50- by 100-foot rectangular grid and along several detailed profiles. The observed field had broad positive and negative anomalies that were similar to modeled anomalies due to thickness variations in a layer of uniformly magnetized material. It was not comparable to the anomalies due to induced magnetization in multiple, randomly located, randomly sized, independent spheres, suggesting that demagnetization may have limited the effective susceptibility of the landfill material. A different 6-acre site survey conducted on a 10- by 10-foot grid was analyzed to determine the maximum station spacing and line separation that could have been used. Essentially, all of the anomalies at this site would have been resolved by a survey conducted on a 20- by 20-foot grid and the larger anomalies would have been detected by a 50- by 50-foot grid.
A significant tonnage of HY-100 steel has been used in the structural designs of new ships and submarines for weight reduction, where HT and HY-80 steels had been previously used. A reduction in hull fabrication costs...
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A significant tonnage of HY-100 steel has been used in the structural designs of new ships and submarines for weight reduction, where HT and HY-80 steels had been previously used. A reduction in hull fabrication costs and higher productivity can be achieved by substitution of an HSLA steel for HY-100. The significant factor in cost savings through use of HSLA steel in fabrication is the reduction or elimination of preheat for welding. Based on the success of the HSLA-80 steel system, a program was initiated to develop and certify an HSLA-100 steel as a replacement for HY-100 in order to reduce fabrication costs. The alloy development and evaluation to support the certification of HSLA-100 steel plate and weldments for surface combatant structural and ballistic protection applications are summarized. HSLA-100 development consisted of three phases: (1) laboratory alloy development to formulate an interim specification; (2) trial steel mill plate production; and (3) plate production for the certification program. An interim specification for HSLA-100 steel plate was used as the basis for the commercial production of over 200 tons of HSLA-100 by domestic steel plate mills. The alloy design of HSLA-100 represents a significantly different metallurgy and microstructure than HSLA-80 steel, but retains the wettability of very low carbon steel. The certification program was conducted to establish the properties, welding characteristics, fabricability, and structural performance of HSLA-100 steel plate over a range of gages from 1/4 to 3 3/4 inches. The certification program included the characterization of production HSLA-100 steel plate mechanical, physical, and fracture properties; evaluation of wettability and welding process limits for structures of high restraint; studies of fatigue properties and effects of marine environments on HSLA-100; and the fabrication and evaluation of large scale structural models to validate the laboratory developed welding process parameters
The estimation of an absolute life expectancy of a structure is a complex process and the results are expected to have relatively large levels of uncertainty. In this study, a comparative analysis is undertaken betwee...
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The estimation of an absolute life expectancy of a structure is a complex process and the results are expected to have relatively large levels of uncertainty. In this study, a comparative analysis is undertaken between two different patrol boats. This is an approach which results in a higher confidence level because certain factors common to both boats can be eliminated by assuming them to be at constant normal levels. The study is limited to the critical forward bottom plating and takes into account the differences in material, plate dimensions, operational profile, structure and loading of the two vessels. Two failure modes, plastic plate deformation and fatigue, are considered, and a novel approach to plate wastage is included. Many factors affect the structural life of a vessel. They include structural type, operational profile, structural details, loads, inspection and maintenance, design methods, safety factors, corrosion, and environmental factors. There are three types of uncertainty associated with these factors; namely, physical randomness, statistical uncertainties, and model uncertainties. The methoddescribed is designed to address these uncertainties. The objective of the paper is to present the reliability-based structural life assessment method, and then to use it to evaluate and compare the structural performance of the forward bottom plating of the two patrol boats. The results of the evaluation are presented in the form of graphs and tables in order to facilitate the comparative evaluation. The method is performed within a computer-based format which allows parametric sensitivity analysis of several variables including the size of the plating panel, thickness, operational profile and loading. The sensitivity of the structural life expectancy of the forward bottom plating to variations in these parameters is evaluated.
作者:
BERKOWITZ, dBDavid B. Berkowitz
VMD Ph.D. is with the Food Safety and Inspection Service U.S. Department of Agriculture South Building Room 4911 Washington DC 20250. These opinions are the author's own and do not necessarily reflect those of the Food Safety and Inspection Service.REFERENCES Seidel G.E. 1989. Genetics in the Pasture. Technology Review. 92: 42.|ISI|Hayes A.W. 1982. Principles and Methods of Toxicology. Raven Press New York.Capecchi M.R. 1989. Altering the genome by homologous recombination. Science 244: 1288.|Article|PubMed|ISI|ChemPort|Ross E.M. and Gilman A.G. 1985. In The Pharmacological Basis of Therapeutics. A. G. Gilman L. S.Goodman T. W.Rall and F. Murad (eds.) Macmillan Publishing Company New York.Darnell J. Lodish H. and Baltimore D. 1986. Molecular Cell Biology. Scientific American Books New York.Stuber C.W. and Goodman M.M. 1983. Allozyme genotypes for popular and historically important inbred lines of corn Zea mays L. U.S. Department of Agriculture ARR-S-16. Washington DC.Nevo E. 1978. Genetic Variation in Natural Populations:Patterns and Theory. Theoretical Population Biology 13: 121.|PubMed|ISI|ChemPort|Bell K. 1983. The blood groups of domestic animals In Red Blood Cells of Domestic Animals. N. S. Agar and P. G. Board (eds.) Elsevier Amsterdam.Jacob F. 1982. The possible and the actual. Pantheon Books New York.Yanagisawa M. Kurihara H. Kimura S. Tomobe Y. Kobayashi M. Mitsui Y. Yazaki Y. Goto K. and Masaki T. 1988. A novel potent vasoconstrictor peptide produced by vascular endothelial cells. Nature 332: 411.|Article|PubMed|ISI|ChemPort|Granger D.N. Barrowman J.A. and Kvietys P.R. 1985. Clinical Gastrointestinal Physiology. W.B. Saunders Company Philadelphia.Smith E.L. Hill R.L. Lehman I.R. Lefkowitz R.J. Handler P. and White A. 1983. Principles of Biochemistry. McGraw-Hill Book Company New York.Goodman R.M. Hauptli H. Crossway A. and Knauf V.C. 1987. Gene transfer in crop improvement. Science 236: 48.|ISI|ChemPort|Gi
作者:
ZITZMAN, LHFALATKO, SMPAPACH, JLDr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group
Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin
This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis comp...
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This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computer architecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computer architecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages anddevelopment environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination anddevelopment of a coherent multi-warfare tactical picture supporting the future combatant command st
作者:
THOMSEN, KOCHAUdHRY, MAdOVANTZIS, KRIESING, RRKurt O. Thomsen
Ph.D. CPG is a project manager with PRC Environmental Management Inc. (303 E. Wacker Dr. Chicago IL 60601). He has 18 years of experience in performing hydrogeologic investigations hazardous waste site remedial actions and feasibility studies RCRA and CERCLA compliance evaluations and field investigations. He has planned and directed two Superfund projects as well as numerous remedial investigations for industrial clients. Thomsen received a B.A. in mathematics and an M.S. in earth science from Northeastern Illinois University and a Ph.D. in environmental engineering from the Illinois Institute of Technology. He is a registered geologist in Delaware Indiana and Virginia. Majid A. Chaudhry
Ph.D. P.E. is a project manager with PRC Environmental Management Inc. (303 E. Wacker Dr. Chicago IL 60601). He has more than 17 years of experience in environmental management including remedial investigations feasibility studies design of waste treatment processes water quality monitoring and hydrogeologic assessment. Chaudhry received a Ph.D. in environmental engineering from West Virginia University and is a registered professional engineer in Illinois Ohio and Tennessee. Kostas Dovantzis
Ph.D. is a project environmental engineer with PRC Environmental Management Inc. (303 E. Wacker Dr. Chicago IL 60601). He has experience in conceptual design of water and waste water treatment processes feasibility studies and mathematical modeling of the fate and transport of organic contaminants in aquatic environments and engineered systems. Dovantzis received a Ph.D. in environmental engineering from the University of North Carolina in Chapel Hill. Ronald R. Riesing
P.E. is a group leader with PRC Environmental Management Inc. (303 E. Wacker Dr. Chicago IL 60601). He has more than 17 years of experience in environmental management including remedial investigations feasibility studies design of waste treatment processes and water quality monitoring. Riesing received an M.S. in engineerin
Ground water remediation of volatile organic compound (VOC) contamination at a site in Michigan was initiated as a result of a consent agreement between the Michigan department of Natural Resources (MdNR) and the resp...
Ground water remediation of volatile organic compound (VOC) contamination at a site in Michigan was initiated as a result of a consent agreement between the Michigan department of Natural Resources (MdNR) and the responsible party. Under the direction of the MdNR, the responsible party conducted a remedial investigation/feasibility study using federal guidelines to define the extent of contamination at the site and to select a response action for site remediation. The selected alternative included a combination of ground water extraction, treatment, and recharge, and soil flushing. The extraction system withdraws ground water from various depths in heavily contaminated areas. The ground water is treated using an air stripper. A spray distribution system spreads effluent from the stripper over a recharge basin constructed over the most contaminated areas. Additional contaminant removal is achieved by volatilization from the spray and percolation through the gravel bed. Recharge water moves downward through the contaminated soils, thus flushing residual soil contaminants. The initial operating data demonstrated that the system can effectively remove trichloroethylene (TCE) from ground water (approximately 95 percent overall removal efficiency). The annualized capital and operation and maintenance (O & M) costs of the remedial action were estimated for several operating periods (15, 20, and 30 years).
作者:
KYRTATOS, NPNICHOLAS P. KYRTATOS
PH.D. is associate professor of marine engineering at the National Technical University of Athens Greece. He obtained a 1st Class Hons. B.Sc. degree in marine engineering from the University of Newcastle upon Tyne (1975) and a Ph.D. degree in mechanical engineering from the Imperial College of Science and Technology London University (1979). He was postdoctoral research associate at Imperial College London (1979–1980). He was visiting professor in the Department of Mechanical Engineering McGill University Montreal Canada (1980–1982). He served at the Greek Airforce Research Centre Athens (1982–1984). He was assistant professor of marine engineering at NTUA (1984–1988).
The increasing use of on-board computers will make the utilization of sophisticated engine simulation models within integrated computerized ship propulsion plant management systems possible. These models can be used t...
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The increasing use of on-board computers will make the utilization of sophisticated engine simulation models within integrated computerized ship propulsion plant management systems possible. These models can be used to provide reference performance data for advanced control, performance optimisation, fault diagnosis, and predictive maintenance systems. This paper describes briefly the structure of advanced engine performance prediction models, commenting on the areas which require further development in view of the above applications. An engine simulation model originally developed on a mainframe computer was adapted to run on a microcomputer. Selected results are presented, using the model to predict the performance of a large slow-speed marine diesel engine, simulating various typical fault conditions.
作者:
RAINS, dADEAN A. RAINS
PH.D is president Decision Engineering Pascagoula Mississippi and has been an active member of ASNE since 1970 a frequent contributor to theNaval Engineers Journal and a participant at ASNE Day meetings as both an author and discusser. He was chairman of the Cruiser Destroyer and Frigate Technology Symposium held in Biloxi Mississippi in 1982. He was paper chairman for the 1986 Symposium. He is currently Councilor in the Pascagoula Section of ASNE. He has been program chairman of the Pascagoula Section for the past two years. He has 33 years of engineering experience and is a graduate of the California Institute of Technology from which he received his B.S. M.S. and Ph.D. degrees all in mechanical engineering.
The usual design approach for combatants is to select the combat system and ship performance parameters and then determine all of the ship characteristics including the power plant size. described in this paper is an ...
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The usual design approach for combatants is to select the combat system and ship performance parameters and then determine all of the ship characteristics including the power plant size. described in this paper is an alternative design approach wherein the power plant and electrical plant are selected after a sustained speed is chosen. Then the hull design, propulsor, transmission system and the various other subsystems can be selected to maximize the payload. The payload items are selected to match the weight and space available. The implication of the hull, mechanical and electrical (HM&E) selections are discussed. A series of examples is used to illustrate the importance of sustained speed, hull form, drag reduction approaches, propulsor and subsystem selection on payload size or combat system capability. The approach can also be used to assess the merits of various HM&E technologies for increasing the size of allowable payload. Twenty technologies are assessed using this approach and compared to each other for payload weight and volume increases. Four power limited ship designs, all using two gas turbine engines for main propulsion power, are compared in detail as examples of the approach. The designs are compared and assessed using survivability and mission effectiveness analyses. This assessment may assist and guide future design efforts. The viability and value of the power limited approach is discussed and conclusions are drawn.
作者:
EMERY, FTWU, JLDr. Franklin T. Emery:is a senior engineer in the Electromechanical Systems Department at the Westinghouse R&D Center
Pittsburgh Pa. Dr. Emery received his B.S. (1974) M.S. (1977) and Ph.D. (1983) degrees in electrical engineering from the University of Pittsburgh Pittsburgh Pa. His primary work is in applied research on electrical systems associated with large power systems both for Navy ship applications and for the commercial power industry. He is presently involved in the development of the electronics for a high current high speed interrupter for use in the protection of power distribution systems on board Navy surface ships. His prior experience is in fiber optic technology design and application for both SDI and Navy applications. He is a Senior Member of IEEE and is a professional registered engineer in Pennsylvania and Florida. Dr. Jiing L. Wu:is a senior research scientist in the Electromechanical Systems Department at the Westinghouse R&D Center
Pittsburgh Pa. Dr. Wu received his B.S. degree in mechanical engineering from Taiwan Cheag Kung University Taiwan in 1965 M.S. in mechanical engineering from the University of Wisconsin Madison in 1969 and Ph.D. in engineering science from the State University of New York Buffalo New York in 1974. He has participated in research and development work in pulsed power switching devices for electromagnetic launchers circuit breakers for commercial and naval electrical systems and fault current limiting devices. He is presently the principal investigator and project manager of a team developing the current limiting protector for the Naval Sea Systems Command.
A pyrotechnic current limiting interrupter (CLI) has been developed for use in high current, 60-Hz, 480-volt, 3-phase electrical bus circuits. The interrupter design combines a high continuous current (4800 A rms) rat...
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A pyrotechnic current limiting interrupter (CLI) has been developed for use in high current, 60-Hz, 480-volt, 3-phase electrical bus circuits. The interrupter design combines a high continuous current (4800 A rms) rating with a high current (210 kA rms sym.) interruption capability. Its electrical power loss is low and its mechanical construction uses no complex moving mechanisms. The CLI is used with a current sensor, electronic logic, and energy storage circuitry. The current sensor continuously monitors the current through the CLI and provides input to logic circuits which analyze anddetermine the validity of the fault condition. Both the fault current magnitude and rate of current increase are used in combination to make the decision when to activate the CLI. Using stored electrical energy, a detonator is activated causing an explosive cord to generate shock waves sufficient to cut the current carrying conductors. detection and initiation of the interruption process occurs within 1/4 cycle for a symmetrical fault and within 1/2 cycle for an asymmetrical fault. The first peak in the fault current is limited to the first half cycle.
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