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ADVANCED AVIONICS ARCHITECTURE - THE NAVAIR STUDY

NAVAL ENGINEERS JOURNAL 1994年第6期106卷 31-40页

作者： KATZ, RS JAHNKE, L JEWETT, CE Cdr. Larry Jahnke USN:is presently Head of the Architecture Branch of the Avionics Engineering division AIR-546 of the Naval Air Systems Command. Among his current responsibilities is to lead implementation activities of the NAVAIR Advanced Avionics Architecture study described in this paper. Cdr. Jahnke graduated from the University of Minnesota with a B.S. degree in aeronautical engineering and was commissioned in 1974. After flight training as a Naval flight officer he was assigned to Naval Air Station Barbers Point Hawaii where he served as Tactical Coordinator for P-3B aircraft. He was assigned to the Communications Directorate of the Joint Staff in 1990 where he participated in support of Desert Shield/Desert Storm and was part of the original cadre of officers responsible for the “C41 for the Warrior” concept. Cdr. Jahnke also has a Master of Science degree from the University of Southern California and is a 1990 graduate of the Industrial College of the Armed Forces. Cdr. Charles E. Jewett USN:is currently the Common Avionics Requirements Officer for Naval Aircraft Programs. He has served the Navy as an Aeronautical Engineering Duty Officer since 1982 with previous defense acquisition assignments as the Avionics Architecture and Engineering Branch Head Fighter/Attack Avionics systems Engineering Branch Head and A-12 Avionics Officer and A-6F Deputy Program Manager and the A-6 Avionics Officer. Cdr. Jewett entered the Navy as an Aviation Officer Candidate in 1971 receiving his commission and earning his wings as a Naval Flight Officer the same year. After graduating from the U.S. Naval Test Pilot School in 1976 he was assigned to the Strike Aircraft Test Directorate of the Naval Air Test Center where he participated in various electronic warfare electro-optics and software update evaluations for A-6 EA-6B and OV-10 aircraft. In Cdr. Jewett's previous assignment at NAVAIRSYSCOM he led a major Avionics Architecture Study (the subject of this paper) that surveyed cutting-edge avionics technol

To establish a planning basis for future avionics systems, the Naval Air systems Command (NAVAIR) conducted an avionics architecture investigation during 1992-1993, culminating in a final report published in August 1993. In the course of the study, U.S. Industry provided significant information to a NAVAIR avionics database for both technologies and systems integration methods. From the study emerged an implementation strategy to allow NAVAIR to develop effective avionics systems in the future that use commercial products and standards where applicable but also allow the ready use of new and emerging technologies. Recommended strategies concentrate on the development process, especially the use of sound systems engineering techniques and the maximum practical use of commercial standards and products. This paper reviews the methodology employed during the NAVAIR investigation, and presents the key findings and resulting implementation strategies. The paper concludes with a brief summary of current implementation plans at NAVAIR.

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FUEL-CELL POWER-PLANTS FOR SURFACE FLEET APPLICATIONS

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NAVAL ENGINEERS JOURNAL 1994年第3期106卷 59-76页

作者： GOUBAULT, P GREENBERG, M HEIDENREICH, T WOERNER, J Philippe Goubault:graduated in 1983 from the “Ecole Nationale Superieure de Techniques Avancees” in Paris with a major in naval architecture. After one year of military service with the French navy he worked as naval architect and program director for the French navy between 1984 and 1988. He was in charge of the development of AGNES200 Surface Effect Ship design which completed its sea trials in 1992. He also was responsible for the construction of five ships (four hydrographic vessels and one experimental MCM vessel) which entered service between 1988 and 1991. He has been involved in a number of projects and studies for the U.S. Navy U.S. Coast Guard and other foreign and domestic customers. At Band Lavis & Associates Inc. Mr. Goubault has expanded the computer tools used to conduct parametric analysis of advanced hullforms and has developed cost-effectiveness assessment tools and methodologies for both commercial and military ships. Mr. Goubault is a member of ASNE. Marc Greenberg:is employed as a cost analyst at the cost and economic analysis branch systems assessment and engineering division Naval Surface Warfare Center. He provides cost estimates and analyses of Navy ship and submarine technologies and has assisted in the development of parametric cost models since 1991. Employed as an electronics engineer by the U.S. Army Information Systems Command from 1989 to 1991 he provided support in simulation design and construction of high frequency and microwave communication systems. Mr. Greenberg received his BS degree in ceramic science and engineering from the Pennsylvania State University May 1987. He is a member of MORS. Todd Heidenreich:is employed in the design analysis and tools branch systems assessment and engineering division of the Carde-rock Division Naval Surface Warfare Center. He is involved as a project naval architect in the conceptual design of future surface ship designs future technology impact assessments and the assessment of current domestic and foreign surface ship desig

This paper describes the results of a study undertaken to determine the impact of fuel cell technology on the design and effectiveness of future naval surface combatants. The study involved the collection of data to characterize four different fuel cell technologies: proton exchange membrane, molten carbonate, phosphoric acid, and solid oxide fuel cells. This information was used to expand current computer models to develop specific fuel cell plants that met the power requirements for several applications on a nominal 5000 Lton destroyer and a nominal 2000 Lton corvette. Each of the fuel cell technologies was incorporated into several applications aboard the destroyer and the corvette. These applications included combinations of centralized and distributed ship service power, and propulsion power. In addition, the impact of fuel cell technology was determined for a ship service power backfit option aboard a DDG-51 class destroyer. The results of the impact on the ship designs were analyzed and a military effectiveness assessment was conducted to address such issues as the impact of fuel cells on mobility, survivability, affordability, and on the environment. The paper identifies which aspects of the fuel cell technologies have the greatest impact upon the ship designs and their operational costs. Recommendations are given for future technology development efforts required to make fuel cells suitable for Navy service.

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THE CALLING(SM) NETWORK - A GLOBAL WIRELESS COMMUNICATION-SYSTEM

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 45-61页

作者： TUCK, EF PATTERSON, DP STUART, JR LAWRENCE, MH Calling Communications Corporation. 1900 West Garvey Ave South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation manufactures of Global Positioning System receivers Applied Digital Access manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl

There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion Laboratory and on recently-declassified work done on the Strategic Defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.

关键词： LOW EARTH ORBIT SATELLITE COMMUNICATIONS FAST PACKET SWITCHING EARTH FIXED CELLS ADAPTIVE ROUTEING LIGHT SPACECRAFT K(A) BAND PHASED-ARRAY ANTENNAS

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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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On the discrepancy between serial and parallel of zero-knowledge protocols 12th

On the discrepancy between serial and parallel of zero-knowl...

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12th Annual International Cryptology Conference, CRYPTO 1992

作者： Sakurai, Kouichi Itoh, Toshiya Computer and Information Systems Laboratory Mitsubishi Electric Corporation 5-1-1 Ofuna Kamakura247 Japan Department of Information Processing Interdisciplinary Graduate School of Science and Engineering Tokyo Institute of Technology 4259 Nagatsuta Midori-ku Yokohama227 Japan

ISBN: (纸本)9783540573401

In this paper, we investigate the discrepancy between a serìal version and a parallel version of zero-knowledge protocols, and clarify the information "leaked" in the parallel version, which is not zero-knowledge unlike the case of the serial version. We consider two sides: one negative and the other positive in the parallel version of zero-knowledge protocols, especially of the Fiat-Sbamir scheme. © Springer-Verlag Berlin Heidelberg 1993.

关键词： computers

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PERFORMANCE TESTING OF SHIPBOARD ELECTRONIC systems

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NAVAL ENGINEERS JOURNAL 1993年第3期105卷 118-124页

作者： HARDER, G MARTIN, RA PE George Harder:is an electronics engineer for Naval Undersea Warfare Center Detachment Norfolk's Electromagnetic Engineering Branch located at the Norfolk Shipboard Electronic Systems Evaluation Facility (SESEF) site. He is responsible for fleet electromagnetic readiness (FEMR) inspections on board Navy ships and provides computer programming support to SESEF. Mr. Harder has a bachelor of science degree in electrical engineering from the University of Florida and has qualified for his professional engineering license in the state of Virginia. Robert A. Martin:is a supervisor electronics engineer employed by the Naval Undersea Warfare Center Detachment Norfolk. He functions as the branch head for the Electromagnetic Engineering Office which is responsible for the operation of the Norfolk Shipboard Electronic Systems Evaluation Facility (SESEF) and the Fleet Electromagnetic Readiness (FEMR) Program. Mr. Martin received a bachelor of science degree in electrical engineering from the University of Akron.

Performance evaluation of shipboard electronic systems entails debugging the systems in a laboratory environment, placing them in service and relving on svstem operators to provide feedback. General testing can be performed at selected sites by system designers, but each site where equipment is to be installed can offer unique problems. It is impossible to predict all the scenarios. Unique problems are more the rule than the exception when equipment is destined for Navy ships. Ship deployments make for difficult logistics when sending test teams to evaluate system failures. So, out of necessity, if newly installed equipment receives the proper inputs and generates the proper outputs, it is accepted and becomes the sailor's responsibilitv to maintain. In cases where documentation is ambiguous or incomplete, it is left to the sailor's ingenuity to continue testing and training on equipment. This is generallv obtained through computer simulations and back-to-back testing which can provide results for ideal conditions, but does not take the dynamics of interference into account. Remote site testing is the only way to get a true representation of equipment performance and training problems. Electronic system operators on board Navy vessels are fortunate, thev have help. There exists an organization available near major naval ports worldwide whose existence is to test electronic systems performance. The testing utilizes electronic systems as they would normally be configured for operations. This organization is the Shipboard Electronic Svstem Evaluation Facility (SESEF).

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Binding Energies of Double-Λ Hypernuclei and ΛΛG-Matrix

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Progress of Theoretical Physics 1993年第1期89卷 109-117页

作者： Himeno, Hiroyuki Sakuda, Toshimi Nagata, Sinobu Yamamoto, Yasuo Graduate School of Science and Technology Niigata University Niigata 950-21 Department of Physics Miyazaki University Miyazaki 889-21 Department of Computer Science and Systems Engineering Miyazaki University Miyazaki 889-21 Institute for Nuclear Study University of Tokyo Tanashi 188 and Physics Section Tsuru University Tsuru 402*)

Binding energies of double-Λ hypernuclei10ΛΛBe,13ΛΛB and6ΛΛHe are calculated on the basis ofG-matrix theory in finite nuclei. The core + Λ+ Λ three-body model is adopted and theG-matrix for ΛΛ interaction is treated consistently with the model space. As the bare interaction the Nijmegen model D and model F are used. It is discussed that the consistency of the interaction with the model space is very important to calculate reliably the binding energies. It is shown that if the new event of double-Λ hypernuclei is interpreted as13ΛΛB, model D reproduces the experimental data very well, whereas model F does not.

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AN OVERVIEW OF IN-SITU AIR SPARGING

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GROUND WATER MONITORING AND REMEDIATION 1993年第4期13卷 127-135页

作者： JOHNSON, RL JOHNSON, PC MCWHORTER, DB HINCHEE, RE GOODMAN, I Dr. Richard L. Johnson is an associate professor in the Department of Environmental Science and Engineering at the Oregon Graduate Institute (P.O. Box 91000 Portland OR 97291). He is also the director of the OGI Center for Groundwater Research and the OGI Large Experimental Aquifer Program. Dr. Paul C. Johnson is a senior research engineer at Shell Development Co. (Westhollow Research Center P.O. Box 1380 Houston TX 77251). Dr. David B. McWhorter is a professor in the Department of Agricultural and Chemical Engineering at Colorado State University (Engineering Research Center Foothills Campus Fort Collins CO 80523). Dr. Robert Hinchee is a research leader in the Environmental Technology Department at Battelle Memorial Institute (505 King Ave. Columbus OH 43201). Iris Goodman is an environmental scientist with the Advanced Monitoring Systems Division at the U.S. EPA Environmental Monitoring Systems Laboratory (P.O. Box 93478 Las Vegas NV 89192).

In situ air sparging (IAS) is becoming a widely used technology for remediating sites contaminated by volatile organic materials such as petroleum hydrocarbons. Published data indicate that the injection of air into subsurface water saturated areas coupled with soil vapor extraction (SVE) can increase removal rates in comparison to SVE alone for cases where hydrocarbons are distributed within the water saturated zone. However, the technology is still in its infancy and has not been subject to adequate research, nor have adequate monitoring methods been employed or even developed. Consequently, most IAS applications are, designed, operated, and monitored based upon the experience of the individual practitioner. The use of in situ air sparging poses risks not generally associated with most practiced remedial technologies: air injection can enhance the undesirable off-site migration of vapors and ground water contamination plumes. Migration of previously immobile liquid hydrocarbons con also be induced. Thus, them is an added incentive to fully understand this technology prior to application. This overview of the current state of the practice of air sparging is a review of available published literature, consultation with practitioners, a range of unpublished data reports, as well as theoretical considerations. Potential strengths and weaknesses of the technology are discussed and recommendations for future investigations given.

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HYDROCARBON VAPOR DIFFUSION IN INTACT CORE SLEEVES

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GROUND WATER MONITORING AND REMEDIATION 1993年第1期13卷 139-150页

作者： OSTENDORF, DW MOYER, EE XIE, YF RAJAN, RV David W. Ostendorf (Civil Engineering Department University of Massachusetts Amherst MA 01003) is an associate professor in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Ostendorf is a Registered Professional Engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Ground Water Association. Ellen E. Moyer (Civil Engineering Department University of Massachusetts Amherst MA 01003) is a doctoral candidate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst with an M.S. degree in environmental engineering from that institution. Her research interests include subsurface investigation soil venting bioremediation and analytical modeling of subsurface contamination. She has six years of professional experience managing hazardous waste site investigation and cleanup projects and is a member of the National Ground Water Association and the American Society of Civil Engineers. Yuefeng Xie (Civil Engineering Department University of Massachusetts Amherst MA 01003) is a postdoctoral research associate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include environmental analyses drinking water treatment and the chemical characterization and removal of disinfection by-products. A graduate with a Ph.D. and an M.S. in environmental engineering and a B.S. in chemistry and chemical engineeering from Tsinghua University Beijing China Xie is a member of the American Water Works Association and the Water Poll

The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors out of residually contaminated sandy soil from the U.S. Environmental Protection Agency (EPA) field research site at Traverse City, Michigan, was measured and modeled. The headspace of an intact core sleeve sample was swept with nitrogen gas to simulate the diffusive release of hydrocarbon vapors from residual aviation gasoline in and immediately above the capillary fringe to a soil-venting air flow in the unsaturated zone. The resulting steady-state profile was modeled using existing diffusivity and air porosity estimates in a balance of diffusive flux and a first order source term. The source strength, which was calibrated with the observed flux of 2,2,4-TMP leaving the sleeve, varied with the residual gasoline remaining in the core, but was independent of the headspace sweep flow rate. This finding suggested that lower soil-venting air flow rates were in principle as effective as higher air flow rates in venting LNAPL vapors from contaminated soils. The saturated vapor concentration ratio of 2,2,4-TMP to 2,2,5-TMH decreased from 6.6 to 3.5 over the duration of the experiments in an expression of distillation effects. The vertical profile model was tested against sample port data in four separate experiments for both species, yielding mean errors ranging from 0 to -24 percent in magnitude.

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Interactive analysis of propagation in optical fibers

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computer Applications in engineering Education 1993年第3期1卷 197-197页

作者： Aicklen, G.H. Tamil, L.S. Erik Jonsson School of Engineering and Computer Science and Center for Applied Optics The University of Texas at Dallas Richardson 75080 Prior to returning to graduate study in 1987 Mr. Aicklen had industrial experience with the Defense Systems and Electronics Group at Texas Instruments in Dallas. In 1985 he left Texas Instruments to pursue a private venture. In 1987 he joined the staff of The University of Texas at Dallas as a research associate in the Erik Jonsson School of Engineering and Computer Science. Mr. Aicklen's research interests include fiber optics nonlinear guided wave optics integrated optical devices and numerical methods in optics. Dr. Tamil is a member of Sigma Xi Optical Society of America Electromagnetics Academy and is a elected member of Commission B and D of the International Union of Radio Science.

We have developed a set of computer codes that compute the propagation constants and field patterns for the propagating modes of cylindrical optical fibers. From a simple set of finite difference equations, solutions of the scalar Helmholtz wave-equation may be computed across a range of normalized frequencies to generate curves describing the dispersion characteristics of the fiber. Accurate cutoff frequencies for any mode can also be computed. We designed the computer codes around α-index profiles since these profiles have been extensively covered in the literature, but our system also supports arbitrary profiles within the limits of the “small index gradient” and “weakly guiding” approximations. The computer codes are accurate and fast. They may be used interactively to explore dispersion in optical fibers and the effects of finite cladding width on dispersion.

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