检索结果-内蒙古大学图书馆

PILOT-STUDY RISK ASSESSMENT FOR SELECTED PROBLEMS AT 3 UNITED-STATES-DEPARTMENT-OF-ENERGY FACILITIES

ENVIRONMENT INTERNATIONAL 1994年第5期20卷 585-604页

作者： HAMILTON, LD HOLTZMAN, S MEINHOLD, AF MORRIS, SC PARDI, R ROWE, MD SUN, C ANSPAUGH, LR BOGEN, KT DANIELS, JI LAYTON, DW MCKONE, TE STRAUME, T ANDRICEVIC, R JACOBSON, RL Biomedical and Environmental Assessment Group Department of Applied Science Brookhaven National Laboratory Upton NY 11973-5000 USA Radiological Sciences Division Department of Advanced Technology Brookhaven National Laboratory Upton NY 11973-5000 USA Health and Ecological Assessment Division Geosciences and Environmental Research Program Physics Department Lawrence Livermore National Laboratory Livermore CA 94551-9900 USA Desert Research Institute Water Resources Center University and Community College System of Nevada Las Vegas NV 89132-0040 USA

Objective and realistic human health risk assessments were performed for environmental problems at the Savannah River Site (SRS), the Fernald Environmental Management Project (FEMP), and the Nevada Test Site (NTS). At the SRS, cancer mortality risks were analyzed for projected public exposures to H-3 and Cs-137 released into the Savannah River. For annual human exposures to SRS tritium in Savannah River water, calculated incremental individual lifetime risks in two human receptor populations were small (8x10(-7);upper 95 percentile point of the distribution). The 95th percentile point of the distribution for incremental individual lifetime risks from one year's exposure to Cs-137 is less than 10(-8). No deaths are expected in either population as a result of exposures to tritium or cesium released to the Savannah River from the SRS. Routine releases of radon and radon progeny from the K-65 silos at FEMP resulted in individual lifetime risks greater than 1x10(-4) only for onsite workers and fenceline residents. Population risks were less than 1.0 for all identified receptor populations. Assessment of risks from exposure to uranium in ground water released by the FEMP predicted no toxic effects for human receptors. All estimated cancer risks were small. The largest predicted no individual lifetime risk was for a well close to the facility (1.3x10(-5)). For the various above-ground shot sites at the NTS, the highest predicted lifetime cancer risks are for a resident farmer, assuming a loss of institutional control, and exceed 1x10(-4) at the 95th cumulative percentile level. At 50 000 and 100 000 y in the future, the predicted cancer risks are all below 10(-6). In the assessment of exposure to radionuclides in ground water at the NTS, for an individual onsite near the site boundary, the geometric mean of the maximum potential excess lifetime risk of cancer mortality for an individual is 7x10(-3). For an individual using water offsite, the geometric mean of the maximum

关键词：

来源：评论

学校读者我要写书评

暂无评论

ON MODELING PARTITIONED MULTIPROCESSOR SYSTEMS

引用

International Journal of High Speed Computing 1994年第1期6卷 31-53页

作者： LAWRENCE W. DOWDY MICHAEL R. LEUZE Department of Computer Science Vanderbilt University Nashville Tennessee 37235 USA Supported in part by the Alexander von Humboldt Foundation while on leave to the University of Erlangen-Nürnberg Erlangen FRG. Mathematical Sciences Section Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Supported by the Applied Mathematical Sciences Research Program of the Office of Energy Research U.S. Department of Energy.

In recent years, multiprocessor systems have been developed to exploit parallelism within individual programs. However, a multiprocessor system may be used more efficiently if its processors are partitioned among independent parallel programs. The partitioning of a multiprocessor system is addressed in this paper. A simple yet powerful model is proposed for the analysis of various partitioning schemes. The model parameterizes both a multiprocessor system and its parallel workload. Attention is restricted to a multiprocessor system partitioned between two parallel programs. The model is studied to determine (1) when partitioning is worthwhile, (2) the extent of performance improvement under optimal partitioning, and (3) which of three partition scheduling schemes is best.

关键词： Multiprocessor partitioning multiprocessor performance performance modeling sensitivity analysis workload characterization

来源：评论

学校读者我要写书评

暂无评论

Requirements for the development of GIS-based group decision-support systems

引用

Journal of the Association for Information science and Technology 1994年第9期45卷

作者： Marc P. Armstrong Departments of Geography and Computer Science and Program in Applied Mathematical and Computational Sciences 316 Jessup Hall University of Iowa Iowa City IA 52242

Though GIS technology has progressed rapidly during the past decade, the focus of most research and development activity has been placed on the development of single-user systems. A mismatch exists, however, between the widespread single-user model of GIS and the group-based approach to decision making that is often adopted when semistructured public policy issues are addressed. GIS-based spatial analysis and display methods must be expanded to encompass group decision making processes, and new tools must be developed that will enable group members to generate, evaluate, and illustrate the strong and weak points of alternative scenarios and come to a consensus about how to proceed toward a decision. © 1994 John Wiley & Sons, Inc.

关键词：

来源：评论

学校读者我要写书评

暂无评论

ACQUISITION REFORM AND BEST PRODUCT PROCUREMENT - AN ENGINEERING VIEW

引用

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.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A NEAR-OPTIMAL MANHATTAN CHANNEL ROUTER FOR A CLASS OF NETS WITH THE SHIFT-RIGHT-ONE PATTERN

引用

applied MATHEMATICS LETTERS 1993年第6期6卷 65-69页

作者： TUAN, TC Institute of Applied Mathematics (Computer Science Program) National Sun Yat-sen University Kaohsiung Taiwan 80424 People's Republic of China

The Manhattan channel routing problem of providing a one-to-one rectilinear wire connection (horizontal segments on one layer, while vertical segments are on the other) between two sets of terminals which lie on two horizontal lines, with the smallest width, is NP-hard. In this paper, it is studied for m consecutive shift-right-one nets, and a near-optimal router which produces a layout with width at most 2 more than the theoretical lower bound given in [1] is presented.

关键词：

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Theory of The Active Nonlinear Coupler Laser

Theory of The Active Nonlinear Coupler Laser

引用

Nonlinear Guided-Wave Phenomena, NLGW 1993

作者： Walton, Donnell T. Winful, Herbert G. Applied Physics Program University of Michigan 1301 Beal Ave. Rm 1214 Ann ArborMI48109 United States Department of Electrical and Computer Engineering University of Michigan 1301 Beal Ave. Ann ArborMI48109 United States

来源：评论

学校读者我要写书评

暂无评论

TOMAHAWK NITROGEN PRESSURIZATION MAINTENANCE - WHY

引用

NAVAL ENGINEERS JOURNAL 1993年第2期105卷 66-68页

作者： CIARULA, TA NERADKA, VF Cdr. Thomas A. Ciarula: USN was born in Pottstown Pa. He attended Northrop University in Inglewood Calif. where he earned a bachelor of science degree in aircraft maintenance engineering in September 1971. He was selected for Officer Candidate School where he was commissioned an ensign (Aeronautical Maintenance Duty) in August 1972. Cdr. Ciarula has been assigned to VA-37 The AIMD at NAF Kadena Okinawa Japan VXE-6 and the USS Forrestal. He was the wing maintenance for training officer for Air Wing Three at NAS Chase Field in Beeville Tex. and the AIMD officer at NAS Key West Fla. In 1988 Cdr. Ciarula was assigned to the Cruise Missiles Project (PEO-CU) where he was the TASM class desk officer and the director of logistics. While at the Cruise Missiles Project he was awarded his master of science in general administration from Central Michigan University. He is currently assigned to PMA-205 in the Naval Air Systems Command. Vincent F. Neradka:received B.S. and M.S. degrees from the University of Maryland in aerospace engineering in 1964 and 1969 and an MS in technical management from the Johns Hopkins University in 1986. He joined the Johns Hopkins University Applied Physics Laboratory in 1979 working on the Vertical Launching System of the Aegis cruisers. Since that time he has participated in activities on the Phalanx program the SPS-48E radar and long term involvement with the Cruise Missile Program. On the Cruise Missile Program Mr. Neradka has focused on the specification of and testing related to environments. Simulation activities have included modeling of pneumatic systems and NASTRAN dynamic modeling. Mr. Neradka is a registered professional engineer.

This paper discusses the data that were recorded during a three-month accelerated humidity test of two Tomahawk all-up rounds (AURs), one pressurized with dry nitrogen in accordance with the current practice, and the other left unpressurized. Temperature and humidity were recorded inside the canisters and missiles. Data analysis consisted of psychrometric calculations to determine the moisture intrusion into these missiles during the test. The work was carried out in support of a technical effort directed at changing the storage and stowage environmental protection of the Tomahawk missile.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Methods for Determining Vacancy Formation Thermodynamic

引用

MRS Online Proceedings Library 1992年第1期291卷 455-460页

作者： L. Zhao R. Najafabadl D. J. Srolovitz University of Michigan Applied Physics Program Ann Arbor USA Dept. of Materials Science and Engineering University of Michigan Ann Arbor USA

The vacancy formation thermodynamics in six fcc metals Ag, Au, Cu, Ni, Pd and Pt are determined from atomistic simulations as a function of temperature. This investigation is performed using the Embedded Atom Method interatomic potentials and the finite temperature properties are determined within the local harmonic and the quasiharmonic frameworks. We find that the temperature dependence of the vacancy formation energy can make a significant contribution to the vacancy concentration at high temperatures. An additional goal of the present study is to evaluate the accuracy of the local harmonic method under circumstances in which the excess entropy associated with the formation of a defect is very small. Our data demonstrate that while the errors associated with determining the vacancy formation entropy in the local harmonic model are large, a simple extension to the local harmonic method yields thermodynamic properties comparable to that obtained in the quasiharmonic model, but with much higher computational efficiency.

关键词：

来源：评论

学校读者我要写书评

暂无评论

NUMERICAL STUDY OF A 2-POINT CORRELATION-FUNCTION AND LIOUVILLE FIELD PROPERTIES IN 2-DIMENSIONAL QUANTUM-GRAVITY

引用

MODERN physics LETTERS A 1991年第12期6卷 1115-1131页

作者： AGISHTEIN, ME BENAV, R MIGDAL, AA SOLOMON, S Program in Applied and Computational Mathematics Fine Hall Princeton University Princeton NJ 08544–1000 USA Nuclear Physics Department Weizmann Institute of Science Rehovot 76100 Israel Physics Department and Program in Applied and Computational Mathematics Fine Hall Princeton University Princeton NJ 08544–1000 USA Physics Department Hebrew University Jerusalem Israel

Two-point Green's function is measured on the manifolds of a 2-dimensional quantum gravity. The recursive sampling technique is used to generate the triangulations, lattice sizes being up to hundred thousand triangles. The grid Laplacian was inverted by means of the algebraic multi-grid solver. The free field model of the Quantum Gravity assumes the Gaussian behavior of Liouville field and curvature. We measured histograms as well as six momenta of these fields. Our results support the Gaussian assumption.

关键词：

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：