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Medical Imaging II 1988

作者： Aarsvold, J.N. Barrett, H.H. Chen, J. Landesman, A.L. Milster, T.D. Patton, D.D. Roney, T.J. Rowe, R.K. Seacat, R.H. Strimbu, L.M. University of Arizona Program in Applied Mathematics TucsonAZ85721 United States University of Arizona Optical Sciences Center TucsonAZ85721 United States University of Arizona Department of Radiology University Medical Center TucsonAZ85724 United States University of Arizona Department of Physics TucsonAZ85721 United States IBM Corporation General Products Division Department 78G/21-2 TucsonAZ85744 United States University of Arizona Department of Electrical and Computer Engineering TucsonAZ85721 United States

Modular scintillation cameras are gamma cameras with relatively small crystal faces, a small number of photomultiplier tubes (PMTs), and independent processing electronics. Our prototypical module has a 10 cm square crystal face, four PMTs, and digital processing electronics. Scintillation event information is transferred to images by mapping digitized PMT response combinations to optimal position estimates of event locations. In our prototype, a look-up table is used to perform this mapping. To encode scintillation event information more effectively, we use nonlinear compression of each of the PMT signals. Also introduced are logarithmic matched filtering and likelihood windowing, two processing techniques that result from exploitations of the Poisson model of the distribution of photopeak events. Logarithmic matched filtering is a method of obtaining estimates of mean detector response functions having greater accuracy than that indicated by the digitization of the PMT responses. Likelihood windowing is the utilization of a likelihood threshold, rather than the familiar energy window, as a discriminant of photopeak and scatter events. We have implemented each of the above on our prototypical module. Performance characteristics of this module include energy resolution of 10% full width at half maximum (FWHM) at 140 keV and spatial resolution of better than 4mm FWHM over 90% of the crystal. © 1988 SPIE. All rights reserved.

关键词： Photomultipliers

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Rectilinear versus constrained one-dimensional motion

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European Journal of physics 1988年第3期9卷

作者： James M Supplee Keith Andrew Applied Physics Program Stockton State College Pomona NJ 08240 USA Department of Applied Physics and Engineering Physics Stevens Institute of Technology Hoboken NJ 07030 USA Physics Department Eastern Illinois University Charleston IL 61920 USA

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THE IMPROVED 16-INCH GUN WEAPON SYSTEM

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 194-203页

作者： WHITE, RW ANTONIUK, TH LCdr. Richard W. White USN: is a mechanical engineering instructor at the United States Naval Academy. He holds a BS in naval architecture from the Naval Academy (Class of 1977) and an MS in mechanical engineering from the Naval Postgraduate School. An engineering duty officer and a weapons systems subspecialist LCdr. White served as 16-in. ammunition technical direction agent and project manager for battleship improvement programs at the Naval Surface Warfare Center Dahlgren Va. Thomas H. Antoniuk:holds a BS in physics from Seton Hall University and an MBA from the University of Delaware. A Reserve engineering duty officer he has been serving as system analyst for the 16 inch Naval Gunfire Improvement Program for two years at the Naval Surface Warfare Center Dahlgren Va. He previously performed an analysis on the Soviet 100-mm and 130-mm gun systems. He is currently examining the feasibility and operational utility of integrating veloci-meters into the Mk 92 Gun Fire Control System.

The Iowa class battleships are being returned to active service without significant modifications to their 16-inch Gun Weapon System (GWS). The ordnance, 16-in. guns and associated fire control equipment are currently 1940's vintage technology. The reactivation was accomplished without significant modernization to the gun systems due primarily to funding limitations. In the late 1970s naval gunfire had fallen out of vogue and no pressing need for 16-in. GWS improvements existed. With the development and subsequent deployment of the landing craft air cushion (LCAC) and the MV-22A Osprey, naval surface fire support (NSFS) of Marine amphibious operations was reexamined. Specifically, the means of generating supporting fire from surface combatants required extensive analysis. The resulting analysis indicated that the most cost-effective partial solution to the problem was an extensive modernization of the battleship's 16-in./50 GWS. With such a modernization, the range, lethality, and response time of the weapon would be significantly improved. Except for the gun turrets themselves, the 16-in. GWS will be almost completely modernized. Extensive modification of the ordnance and fire control system will be accomplished. This paper first discusses the reasons for the improvement in the 16-in. GWS. It describes, in detail, the new 16-in. ordnance under development, highlighting the operational issues which drive the engineering approach. Finally, the new gun fire control system (FCS) is described. The advantages of streamlining with digital equipment are highlighted. Some unique features of the FCS, which are appropriate in its operational environment, are discussed.

关键词： WARSHIPS

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ROCKET MOTOR DESIGN FOR UNDERWATER SHOCK

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 215-225页

作者： YAGLA, JJ The authorreceived his B.A. degree in science (physics) from the Slate College of Iowa in 1965. He received his M.S. degree in engineering mechanics in 1968 and his Ph.D. in aerospace engineering and engineering science in 1981 from Arizona State University. He has done analytical and experimental research in the field of weapons blast and dynamical response since 1965 at the Naval Surface Warfare Center in Dahlgren Virginia. As a supervisory research mechanical engineer he was previously head of the Physical Response Analysis Branch Blast Effects Branch and Ship Engineering Branch. Dr. Yagla is the test development agent and was test conductor for the gun and missile structural test firings in USSIowaclass battleships. He is a consultant to the Naval Sea Systems Command battleship combat system engineer and the Naval Air Systems Command Cruise Missile Project for blast and structural response. He has been involved in the development of Standard missile and its launching systems since 1969. He participated in the design of shock tests for the Mk 104 rocket motor and analyzed the data. He is presently analyzing shock and vibration problems for the Standard Missile Program Office.

Naval ships and equipment are designed to survive underwater shock. The underwater shock can result from a nearby explosion of a bomb or missile, or the underwater detonation of a nuclear weapon. The shock wave travels through the water and applies an impulsive pressure load to the ship. The ship responds by a sudden acceleration in a direction up and away from the explosion. The motion of the ship is imparted to its weapons and equipment. In the case of Standard missile, impulsive loads are applied to the missiles stowed in the magazines. The evolutionary design of rocket motor chambers and launch shoes for Standard missile for underwater shock is traced from the early Tartar missile to the latest version of Standard missile. As the weight of the missile has increased and the performance requirements have become more demanding, the design of the weapon for underwater shock has become more difficult. The paper explains the design approaches and techniques. Theoretical and experimental methods have been required. Finally, the paper highlights the experiences and problems in conducting underwater shock experiments with production systems in ships at sea.

关键词： WARSHIPS

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Mechanisms for thermally enhanced target coupling by repetitively pulsed lasers

Mechanisms for thermally enhanced target coupling by repetit...

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作者： Jumper, E.J. Jackson, J.P. Couick, J.R. McKee, L.L. Bohn, C.L. Crawford, M.L. Department of Aeronautics and Astronautics Air Force Institute of Technology Wright-Patterson Air Force BaseOH United States Energy Program KAMAN Sciences Corporation Colorado SpringsCO United States Department of Engineering Physics Air Force Institute of Technology Wright-Patterson Air Force BaseOH United States Department of Physics United States Air Force Academy Colorado SpringsCO United States Air Force Weapons Laboatory Kirtland AFBNM United States

This paper describes the results of computations of the heat and mass transfer to and from an aluminum target when irradiated by an intense 10.6 μm laser pulse, for the case when a laser-supported detonation (LSD) wave is ignited. The results of the computations are compared to an experiment performed by Maher and Hall where a thermal-coupling coefficient of 17.5% was observed. The computations indicate that convective and radiative heat transfer alone are unable to explain the high thermal coupling;vapor recondensation is also investigated as a possible mechanism for explaining the observed coupling coefficient, and does appear to be compatible with the observations. Conclusions are drawn about the possible physical mechanisms at work both during the early phases of the pulse and during the time the LSD wave propagates away from the target. © 1987 American Institute of Aeronautics and Astronautics Inc.. All rights reserved.

关键词： Pulsed lasers

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Summary Abstract: A nondestructive synchrotron radiation photoemission study of the band lineup for buried GaSb–AlSb interfaces

Journal of Vacuum Science & Technology B: Microelectronics P...

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Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena 1987年第4期5卷 1286-1287页

作者： D. W. Niles B. Lai J. T. McKinley G. Margaritondo G. Wells F. Cerrina G. J. Gualtieri G. P. Schwartz Department of Physics and Synchrotron Radiation Center University of Wisconsin Madison Wisconsin 53706 Department of Electrical Engineering and Materials Science Program University of Wisconsin Madison Wisconsin 53706 AT&T Bell Laboratories Murray Hill New Jersey 07974

D. W. Niles, B. Lai, J. T. McKinley, G. Margaritondo, G. Wells, F. Cerrina, G. J. Gualtieri, G. P. Schwartz; Summary Abstract: A nondestructive synchrotron radi

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STUDY OF MATCHING LOAD ON NONUNIFORM COAXIAL TRANSMISSION LINE AND ITS APPLICATION TO WIDEBAND IMPEDANCE TRANSFORMER.

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Electronics and Communications in Japan, Part II: Electronics (English translation of Denshi Tsushin Gakkai Ronbunshi) 1987年第8期70卷 43-50页

作者： Sano, Seigo Mochizuki, Manabu Muto, Shinzo Ito, Chiaki Ito, Hiroshi Member Faculty of Engineering Yamanashi University Koufu Japan 400 Nonmember Shinzu Muto graduated from Yamanashi University Dept. of Electrical Engineering in 1970 and completed the Master's program in 1972. He became an Assistant at Yamanashi University Dept. of Electrical Engineering in 1973. He was on leave at Tohoku University in 1979. He has worked on organic dye lasers laser applications and waveguide devices. Member Applied Physics Society and Laser Society. Members

Two nonuniform coaxial transmission lines have been fabricated in which the primary parameters of the line vary parabolically and cosinusoidally. The characteristic impedances and the matched loads have been measured and the application to a broadband impedance transformer has been studied. The results show that the characteristic impedance distribution of the nonuniform coaxial transmission line does not coincide with the nominal characteristic impedance but agrees with the solution of the differential equation for the impedance derived from the telegrapher's equation. The condition providing for an effective matched load is determined and it is found that under this matched condition both of the nonuniform coaxial transmission line elements operate as an impedance transformer over an extremely wide frequency range exceeding 0. 5 GHz.

关键词： TELECOMMUNICATION LINES, HIGH FREQUENCY

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16-IN GUN BLAST AND THE BATTLESHIP REACTIVATION program

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NAVAL ENGINEERS JOURNAL 1987年第3期99卷 227-238页

作者： YAGLA, JJ The authorreceived his B. A. degree in science (physics) from the State College of Iowa in 1965. He received his M. S. degree in engineering mechanics in 1968 and his Ph.D in aerospace engineering and engineering science in 1981 from Arizona State University. He has done analytical and experimental research in the field of weapons blast since 1965 at the Naval Surface Weapons Center in Dahlgren Virginia. As a supervisory research mechanical engineer he was previously head of the Physical Response Analysis Branch Blast Effects Branch and Ship Engineering Branch. Dr. Yagla is the test development agent and was test conductor for the gun and missile structural test firings in USS Iowa class battleships. He is a consultant to the Naval Sea Systems Command battleship combat system engineer and the Naval Air Systems Command Cruise Missile Project for blast and structural response. He is presently analyzing shock and vibration problems for the Standard Missile Program Office.

Reactivated and modernized USS Iowa class battleships employ many new systems, none of which were designed to withstand blast from 16-inch guns. Placement of the new equipment was driven by the need to impose the smallest possible restrictions on the guns. The design problem was complicated by two factors: first, the blast overpressure field surrounding the gun had not been accurately measured with modern instruments. Second, the blast overpressure tolerance of several important systems was unknown. The problem was solved through judicious placement of the equipment so that work could begin on the ship. Meanwhile the pressure surrounding a 16-inch gun was measured at the Dahlgren Laboratory. Mathematical functions describing the blast field were then used to design shipboard experiments in which the guns were fired at progressively more severe angles of train and elevation, while the equipment performance was carefully monitored. Four sets of shipboard experiments were required. Limiting values for the firing arcs have been determined, and the consequences of exceeding the recommended limits are now known.

关键词： WARSHIPS

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SYSTEMS AND EQUIPMENT MAINTENANCE MONITORING FOR SURFACE SHIPS (SEMMSS) program

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NAVAL ENGINEERS JOURNAL 1987年第6期99卷 63-69页

作者： CHAPMAN, CL JOLLEY, R Charles L. Chapman:graduated from the University of Maine with a B.S. degree in engineering physics in 1961. He worked with the General Electric Company from 1961 to 1966 as a field engineer during installation checkout and maintenance of the Talos missile systems. He also became proficient in field engineering support of the Mk 44 and later the Mk 46 torpedo. In 1966 he joined the Naval Underseas Center at Newport RI as a torpedo engineer. In 1967 this functional responsibility was transferred to the newly instituted Naval Ordnance Systems Support Organization Atlantic. After transferring to Naval Sea Support Center Atlantic he became the Torpedo Division head then the ASW Surface Ships' Division head and subsequently was promoted to his present position as SEMMSS program manager Atlantic. He is an extremely active member in ASNÈ receiving the first annual award for the “Top Recruiter.” He is a member of Sigma Pi Sigma the physics honorary society. USN Cdr. Ronald Jolley USN: graduated from Duke University in 1964 with a B.S. degree in mechanical engineering and earned an M.S. degree in electrical engineering in 1974 at the U.S. Naval Postgraduate School Monterey. In his 22 years in the Navy he has served on a number of ships and in ship support assignments. Sea tour assignments included chief engineer electronics material officer and executive officer of a destroyer and main propulsion assistant on an aircraft carrier. His shore assignments included positions as head Tactical Data Systems Division at Commander Operational Test and Evaluation Force executive officer of the Naval Sea Support Center Atlantic SEMMSS project officer Atlantic and currently the staff Commander Naval Forces Korea. Cdr. Jolley is a subspecialist in the material support field both naval engineering and naval electronics. His professional affiliations include membership in Pi Tau Sigma (national honorary mechanical engineering fraternity) since 1963 and Eta Kappa Nu Association (electrical engineering honorary s

The SEMMSS program is a little more than two years old and, like its submarine forerunner Submarine Maintenance Monitoring Support Office (SMMSO), provides many benefits to the fleet support community. Most of these benefits, such as improved readiness, improved repair definition, reduced voyage repairs, and continued technical contact with ships, are of special value. The program, when fully expanded to include combat systems, will provide a methodology for an integrated systems, whole-ship approach to shipboard performance monitoring. This paper presents an overview of the SEMMSS program, addresses implementation of the combat systems portion of the program, and outlines efforts to document program effectiveness.

关键词： WARSHIPS

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EVALUATION OF POTENTIAL RADON EXPOSURE FROM DEVELOPMENT OF GEORGIA PHOSPHATE DEPOSITS.

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Mining engineering 1986年第3期38卷 195-196页

作者： Eichholz, G.G. Ambrose, J.P. Skowroski, M.G. Georgia Inst of Technology Nuclear Engineering & Health Physics Program Atlanta GA USA Georgia Inst of Technology Nuclear Engineering & Health Physics Program Atlanta GA USA

This paper estimates the magnitude of any radon-based health effects that might arise from future mining operations in selected areas of the Georgia coastal region. To do this, a model was developed that took into account the mining operations themselves, the atmospheric dispersion of the radon released, and the radon daughter concentrations in nearby towns. The model was applied to both extremes. The first application was a hypothetical mining operation in Echols County. The second application was a site near Savannah, Georgia.

关键词： PHOSPHATE DEPOSITS

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