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13th Applied Aerodynamics Conference, 1995

作者： Lin, John C. Dominikt, Chet J. Flow Modeling and Control Branch Fluid Mechanics and Acoustics Division NASA Langley Research Center Mail Stop 170 HamptonVA23681-0001 United States Subsonic Aerodynamics Technology Group Advanced Transport Aircraft Development McDonnell Douglas Aerospace 1510 Hughes Way MC 71-35 Long BeachCA90810-1870 United States

ISBN: (纸本)9781563471230

New high-lift components have been designed for a three-element advanced high-lift research airfoil using a state-of-the-art computational method. The new components were designed with the aim to provide high maximum-lift values while maintaining attached flow on the single-segment flap at approach conditions. This three-element airfoil has been tested in the NASA Langley Low-Turbulence Pressure Tunnel at chord Reynolds number up to 16 million. The performance of the NASA research airfoil is compared to a reference advanced high-lift research airfoil. Effects of Reynolds number on slat and flap rigging have been studied experimentally. The performance trend of this new high-lift design is comparable to that predicted by the computational method over much of the angle of attack range. Nevertheless, the method did not accurately predict the airfoil performance or the configuration-based trends near maximum lift. © 1995 by the American Institute of Aeronautics and Astronautics. Inc.

关键词： Airfoils

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ACCURATE DESIGN OF COMPACT FORWARD-COUPLED MICROSTRIP FILTERS USING AN INTEGRAL-EQUATION FIELD SOLVER

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED ENGINEERING 1995年第5期5卷 324-330页

作者： ZHANG, DW LIANG, GC SHIH, CF JOHANSSON, ME WITHERS, RS Conductus Inc. 969 W. Maude Avenue Sunnyvale California 94086 Mane E. Johansson received the BS degree in physics from University of Linkoping Sweden in 1986 where she is now finishing her graduate courses. She joined Conductus Inc. in July 1992. She is currently section head for the device processing group at Conductus. This includes responsibility for process development and production of microwave and MRI/NMR devices and laser deposition of YBCO thin films. She has developed reproducible wet- and dry-etching techniques and passivation methods for processing of these devices. From 1989 to 1991 as a guest researcher at the National Institute of Standards and Technology she developed a process for fabrication of SNS junctions using high temperature superconducting thin films. Ms. Johansson also performed deposition and characterization of these materials. From 1991 to 1992 she was employed at Advanced Fuel Research East Hartford (3 where she was responsible for establishing the processing of YBCO IR-detectors on silicon. Previously she was employed in the microwave technology group at the National Defense Research Institute (FOA) Linkoping Sweden from 1986 to 1989. She developed fabricated and characterized passive microwave devices (based on normal metals).

In this article, we present forward-coupled microstrip filters designed using an integral-equation-based field solver, and fabricated in high-temperature superconducting (HTS) thin films. Two designs were studied, one a nine-pole bandpass filter at 900 MHz with 25-MHz bandwidth, and the other a five-pole bandpass biter at 2 GHz with 24-MHz bandwidth and 10-Ohm resonator characteristic impedance. Both designs were fabricated using YBa2Cu3O7 (YBCO) HTS thin films. Measurements showed excellent agreements with the simulation predictions. For the nine-pole filter design, a measured insertion loss of 0.3 dB, and a measured return loss of 16 dB were achieved in the YBCO filter at 77 K. (C) 1995 John Wiley and Sons, Inc.

关键词： Microwave filters

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AN ENERGY-COST MINIMIZING STRATEGY FOR FERMENTATION DISSOLVED-OXYGEN control

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BIOprocess ENGINEERING 1994年第2期10卷 91-97页

作者： SHIELDS, RW KAO, EI 1. Advanced Process Control Technologies Group Fermentation Process Research and Development Lilly Research Laboratories Eli Lilly and Company Indianapolis USA

A cost-minimizing mathematical model for on-line control of dissolved oxygen using agitation speed and aeration rate was developed. In pilot scale monensin fermentation using Streptomyces cinnamonensis, this algortihm provided stable control of dissolved oxygen at 40%, reducing energy usage 27.8%. The agitation and aeration profiles provided by the algorithm respresent the pathway of least energy cost for control at the desired dissolved oxygen level. Other observed advantages of bivariable control were reduction of foaming, evaporation, and gas holdup. Reduced maintenance of compressors and agitator motors could also be expected due to decreased load. Monensin productivity equivalent to fermentation with constant agitation and aeration was not obtained, however, with potency reduced 14.8% with the dissolved oxygen control strategy.

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ASYNCHRONOUS TRANSFER MODE (ATM) OPERATION VIA SATELLITE - ISSUES, CHALLENGES AND RESOLUTIONS

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 211-222页

作者： CHITRE, DM GOKHALE, DS HENDERSON, T LUNSFORD, JL MATHEWS, N COMSAT Laboratories 22300 Comsat Drive Clarksburg MD 20871 USA. Received his B.Sc. from the University of Bombay India an M.A. in mathematics from the University of Cambridge U.K. and a Ph.D. in physics from the University of Maryland. He is currently an Associate Executive Director of the Network Technology Division at COMSAT Laboratories. He has been involved in research and development activities in ISDN VSAT networks data communications and network systems and architectures. Prior to his current positions Dr. Chitre was a Principal Scientist in the Network Technology Division at COMSAT Laboratories. Dr. Chitre joined COMSAT Laboratories in 1980. He has made major contributions to the analysis and architecture of data communication ISDN and BISDN via satellite. Dr. Chitre directs and participates in the international and national standards activities in ISDN BISDN and data communication as they apply to satellite communication. He was Chairman of the Working Group on Protocols and Network Timing Function of the CCIR/CCITT Joint Ad Hoc Group on ISDN-Satellite Matters during 1990–1992. Currently he is the Chairman of the Working Group on New Technologies in the ITU Intersector Coordinating Group (ICG) on Satellite Matters. Dr. Chitre was a programme manager during 1990 and 1991 on a contract from INTELSAT on systems studies on satellite communications systems architectures for ISDN and broadband ISDN systems. Currently he is the technical manager of the DoD Contract on ATM via satellite demonstration and the programme manager for the INTELSAT contract on analysis and top-level specification of INTELSAT ISDN subnetworks and SDH compatible transport network. Department manager for ISDN/Data Communications in the Network Technology Division of COMSAT Laboratories. His responsibilities include managing the implementation of next generation telecommunication systems for fixed and mobile satellite systems. Current projects include the development of a high data rate gateway switch that provides for the

Key issues regarding the operation of the broadband integrated services digital network (BISDN) via satellite are presented herein. The specific issues, challenges, and their resolutions are detailed. In particular, the impact of error characteristics and propagation delay on the operation of BISDN via satellite is discussed. Solutions are presented for removing adverse effects and providing high-quality service to users of BISDN via satellite.

关键词： ATM BISDN

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HYBRID SATELLITE AND TERRESTRIAL NETWORKS

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 313-327页

作者： CHITRE, DM SHYY, DJ EPHREMIDES, A GUPTA, S COMSAT Laboratories 22300 Comsat Drive Clarksburg MD 20871–9475 USA. Received his B.Sc. from the University of Bombay India an M.A. in mathematics from the University of Cambridge U.K. and a Ph.D. in physics from the University of Maryland. He is currently an Associate Executive Director of the Network Technology Division at COMSAT Laboratories. He has been involved in research and development activities in ISDN VSAT networks data communications and network systems and architectures. Prior to his current positions Dr. Chitre was a Principal Scientist in the Network Technology Division at COMSAT Laboratories. Dr. Chitre joined COMSAT Laboratories in 1980. He has made major contributions to the analysis and architecture of data communication ISDN and BISDN via satellite. Dr. Chitre directs and participates in the international and national standards activities in ISDN BISDN and data communication as they apply to satellite communication. He was Chairman of the Working Group on Protocols and Network Timing Function of the CCIR/CCITT Joint Ad Hoc Group on ISDN/Satellite Matters during 1990–1992. Currently he is the Chairman of the Working Group on New Technologies in the ITU Intersector Coordinating Group (ICG) on Satellite Matters. Dr. Chitre was a programme manager during 1990 and 1991 on a contract from INTELSAT on systems studies on satellite communications systems architectures for ISDN and broadband ISDN systems. Currently he is the technical manager of the DoD Contract on ATM via satellite demonstration and the programme manager for the INTELSAT contract on analysis and top-level specification of INTELSAT ISDN subnetworks and SDH compatible transport network. Received the B.S. degree in electrical engineering from national Chiao-Tung University Hsin-Chu Taiwan in 1983 and the M.S. and Ph.D. degrees in electrical engineering from Georgia Institute of Technology Atlanta GA in 1986 and 1990 respectively. From June 1987 to October 1987 he worked for the Department of Neurology Emory Univers

The role of satellite communications in networks that provide new services, such as frame relay and multimedia, is investigated. Both passive and active (on-board switching/processing) satellite systems are considered. Novel techniques are developed for each system to demonstrate, via detailed analysis and simulation, how the communications bandwidth agility of multipoint/broadcast satellite channels, and the on-board switching/processing, makes it feasible to provide these new services via hybrid satellite and terrestrial networks in a resource-efficient manner.

关键词： HYBRID NETWORKS ON-BOARD processING FRAME RELAY

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ANALYSIS OF A MOVABLE BOUNDARY ACCESS TECHNIQUE FOR A MULTISERVICE MULTIBEAM SATELLITE SYSTEM

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 299-312页

作者： BOHM, S ELHAKEEM, AK MURTHY, KMS HACHICHA, M KADOCH, M Department of Electrical and Computer Engineering Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada . He is ITU's Specialist Consultant and Chief Advisor for a number of ITU/UNDP projects including VSATs Rural Networks Digital Broadc

In this paper, the performance of a new movable boundary accessing (MBA) technique for future integrated services multibeam satellite systems is studied. The multiservice environment considered includes both asynchronous and isochronous traffic consisting of video, voice, file transfer and interactive data. The movable boundary access technique proposed here will maximize the utilization of the up-link frame capacity. It is shown that the potential user population is substantially increased with the use of a moving boundary policy with minimal overhead.

关键词： MOVABLE BOUNDARY ACCESS TECHNIQUE MF-TDMA DAMA MULTIBEAM SATELLITE

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PERFORMANCE OF A PRIORITIZED ON-BOARD BASEBAND SWITCH FOR A MULTISERVICE MULTIBEAM SATELLITE

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 283-297页

作者： BOHM, S ELHAKEEM, AK HACHICHA, M Department of Electrical and Computer Engineering Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada An Associate Director of Advanced Technology & Networks Group VISTAR Telecommunications Inc. Ottawa Canada. He is also an Adjunct Pr

In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, file transfer and interactive data. The prioritized switch uses both input and output buffering, switch speed-up as well as a two-phase head-of-line resolution algorithm, in order to reduce the buffer loss while maintaining acceptable user delays. The minimum required buffer capacity and switch speed-up for each service in a prioritized environment are found under uniform traffic conditions. It is shown that under uniform traffic conditions, only minimal buffering and switch speed-up are needed even for the lowest priority users. The performance dependence on the switch size is also substantially reduced with head of line resolution and buffering even in a prioritized environment.

关键词： SWITCH ON-BOARD BASEBAND MULTIBEAM PRIORITIZED HEAD-OF-LINE UNIFORM LOAD SPEED-UP

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ACQUISITION REFORM AND BEST PRODUCT PROCUREMENT - AN ENGINEERING VIEW

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NAVAL ENGINEERS JOURNAL 1994年第6期106卷 41-57页

作者： FISHER, DA SKOLNICK, A He has been involved with several weapon system developments. Among these were the Trident II fire control and navigation systems the BSY-I Anti-Submarine Warfare System and the Navy standard computers (UYK44 and EMSP). He served as manager of the Digital Circuits Engineering Branch and was then appointed as manager of the Automatic Test Equipment (ATE) Technology Division. As manager of the ATE Technology Division he was responsible for the SP-23 Fire Control System Support Project the SP-24 Navigation Project and the Fleet Progressive Maintenance Program (2M/ATE). This Division was responsible for selection and application of electronic product technology and for developing fleet test and repair techniques. He holds a B.S. in Electrical Engineering from the University of Evansville and is currently pursuing a Masters of Public Administration at Indiana University-Purdue University Indianapolis. Dr. Alfred Skolnick:retired from the Navy in 1983 with the rank of captain. He is president of System Science Consultants (SSC) specializing in strategic planning technical program definition technology assessment and engineering analyses on selected matters of national interest. Dr. Skolnick taught mathematics and management sciences at University of Virginia and Marymount University. He is adjunct faculty at Northern Virginia Community College. From 1985 to 1989 he was president of the American Society of Naval Engineers. In the Navy he served at Applied Physics Laboratory/The Johns Hopkins University then aboard USSBoston(CAG-1) and played leading roles in several weapon system developments inertial navigation (Polaris) deep submergence (DSRV) and advanced ship designs (SES). He later was director Combat System Integration Naval Sea Systems Command and head Combat Projects Naval Ship Engineering Center. In 1975 he became a major project manager and led the Navy's High Energy Lasers Program in 1981 he was assigned all Navy Directed Energy Weapons development efforts. He was vice president advanced tech

The military services are being moved in the direction of performance-based specifications and standards. They are being steered against dictating ''how to'' produce an item since such action forecloses on the ability to gain access to components or technology that may have a commercial equivalent. Why should the engineering community embrace the new approach? Aside from the obvious weight of it being approved policy, therefore currently mandated, it warrants examination because it is the correct approach at this time when applied to appropriate products. Military specifications and standards are to be displaced then, by acceptable alternative contractor design solutions. Industry bidders will be allowed to propose the particular design details, permitting procurement flexibility by contractually citing only system level or interface requirements, both physical and functional. Hopefully, this can broaden the industrial base and increase competition with reduced costs to follow. Conceptually, the approach appears both performance-sensible and cost-attractive (there are, of course, consequent risks) but how does implementation proceed? Is it possible to pursue the goals envisioned along paths that are not in themselves experimental? Can the American postulate, minimal loss of life and limb to U.S. military people, continue to be honored? Experience and track record elsewhere imply encouraging possibilities in select situations-useful prospects are identified and discussed in practical terms.

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LASER CLADDING REFURBISHMENT OF CATAPULT TROUGH COVERS

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NAVAL ENGINEERS JOURNAL 1993年第6期105卷 69-75页

作者： DENNEY, PE LOWRY, RW Paul E. Denney:has been involved with high-powered laser materials processing for over eight years. Mr. Denney received both his BS and MS degrees in metallurgy from MIT in 1980. He was employed for one year by CF&I Steel of Pueblo Colo. before joining the Naval Research Laboratory in Washington D.C. where he was involved with failure analyses and laser materials processing. From 1985 to 1988 Mr. Denney conducted laser materials processing at the Westinghouse Research and Development Center in Pittsburgh Pa. Since 1988 he has been at the Applied Research Laboratory at Pennsylvania State University (ARL Penn State) where he has assisted in the development of the laser metalworking technology transfer facility (in Johnstown Pa.) and the laser processing group within the ARL Penn State Manufacturing Science Department. Mr. Denney directs laser and other advanced thermal processing programs for the Navy Army and many private industrial sponsors. Robert W. Lowry:graduated from Virginia Polytechnic and State University with BS and MS degrees in metallurgical engineering in 1967. He has worked at the Naval Surface Warfare Center for 30 years and has been involved with laser process technology since 1979. Mr. Lowry has worked in fragmentation studies failure analysis materials testing and been associated with such Navy programs as Vertical Launch Standard Missile Guided Projectile and the In-Service Manufacturing Technology Advisory Group (MTAG) Metals Subcommittee. He has submitted two patent applications in laser processing and is current manager of NSWC's high power laser facility. Current emphasis is on laser welding for missile structures. Mr. Lowry has recently been selected as a participant in the Navy Science Advisory Program (NSAP) as a technical advisor at CinCLantFlt Norfolk for fleet maintenance.

A laser cladding process has been developed and is now in production for the cladding of new aircraft carrier catapult components. The Service Life Extension Program (SLEP) Office of Naval Sea Systems Command (NavSea) suggested that this process be utilized for the refurbishment of catapult tracks. Early experiments were conducted by the Naval Surface Warfare Center in conjunction with the IIT research Institute. The program was then transitioned to the Applied research Laboratory, Pennsylvania State University (ARL Penn State) under the sponsorship of the Naval Air Systems Command (NavAir)/Navy MANTECH program, thus providing an effective solution to a NavSea/NavAir interface hardware problem. ARL Penn State was responsible for the production and evaluation of six laser clad aircraft carrier catapult tracks as part of a program sponsored and funded by NavAir Code 5512. Six catapult tracks that had been taken out of service because of excessive wear were laser clad at the Westinghouse Electric research and development Center (Now ''Science and Technology Center'') for ARL Penn State. The composition of the clads was Inconel 625, Stellite 6/Stainless Steel 304, and Ferrelium 255. The tracks were machined and installed on the USS Constellation. Wear measurements were taken for the laser clad tracks and standard tracks ahead and behind the clad tracks. After 7,161 launches, the tracks were removed and returned to ARL Penn State for evaluation. The evaluation indicated that impact damage was observed on one track. No additional defects related to operations were found. Wear data indicated that the wear rate for it was 25%-50% less than non-clad. The results indicated that rejectable tracks (and one piece trough covers) could be successfully laser clad for extended operating life at acceptable costs. With emphasis for the future on a more affordable Navy, the need for viable refurbishment processes will be necessary for extending life and performance for the 21st century

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IMPROVING THE SHIP DESIGN, ACQUISITION AND CONSTRUCTION process

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NAVAL ENGINEERS JOURNAL 1992年第2期104卷 39-57页

作者： RYAN, JC JONS, OP J. Christopher Ryan:earned his bachelor's and master's degrees in Naval Architecture from Webb Institute and MIT respectively. He spent three years at the Advanced Marine Technology Division of Litton Industries working on the DD-963 class ship design and related computer aided design projects. he subsequently went to the Navy Department concentrating on early stage design of surface combatants for 12 years including work on the FFG-7 Sea Control Ship CSGN and CVV aircraft carrier projects. He then shifted focus and became the technical director for the Computer Supported Design Program in NavSea for five years. Mr. Ryan has served in several supervisory positions within the Ship Design Group in NavSea since that time. He is currently the project manager for the Ship Design Acquisition and Construction Process Improvement Project. Otto P. Jons:received a Diplom Ing. in shipbuilding from the Technical University of Hannover W. Germany and an M.S. in naval architecture and marine engineering from the Massachusetts Institute of Technology in 1967. He then joined Litton Ship Systems where he was responsible for the preliminary design of the DD-963 hull structure and then for ship systems as manager LHA Ship Systems Engineering Department. From 1972 to 1974 he was principal research scientist at Hydronautics. In 1976 as technical director he helped establish the local office of Designers and Planners. Otto Jons was one of the co-founders of Advanced Marine Enterprises Inc. in 1976 where he is corporate vice president engineering.

In the spring of 1990, the NavSea Chief Engineer initiated a project to improve the design, acquisition and construction (DAC) of U.S. Navy ships. The project's objectives are to reduce the time and cost of acquiring and operating Navy ships while improving their quality, unlike previous studies on the subject, the project utilizes a rigorous process analysis approach and attempts to use quantitative measures as the basis for recommending improvements. The paper is, of necessity, a status report on the progress of this project. Topics covered include: the DAC process;a look at the current state of ship acquisition time, cost, and quality;the methodology for process improvements;and early findings.

关键词： Naval Vessels

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