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Hot methanol extraction for the analysis of volatile organic chemicals in subsurface core samples from Dover Air Force Base, Delaware

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GROUND WATER MONITORING AND REMEDIATION 1997年第1期17卷 104-121页

作者： Ball, WP Xia, G Durfee, DP Wilson, RD Brown, MJ Mackay, DM William P. Ball is an assistant professor in the Department of Geography and environmental engineering at Johns Hopkins University (313 Ames Hall 3400 N. Charles St. Baltimore MD 21218). His research interests are in the physical and chemical processes that control contaminant fate in aqueous systems both in the natural environment and in engineered processes of treatment and remediation. Recent work has included both laboratory and computer modeling studies related to contaminant fate and transport in subsurface environments. Ball holds M.S. and Ph.D. degrees in environmental engineering and science from Stanford University and a B.S. degree in civil engineering from the University of Virginia. He is a registered pro-fessional engineer in the state of Virginia. Guoshou Xia is a Ph.D. candidate at Johns Hopkins University He was previously a lecturer in the Department of Civil Engineering at Southeast University in China. He received his B.S. degree in chemistry from Hefei University and his M.S. degree in environmental engineering from East China University of Chemical Technology. His current research interests are in the area ofsubsurface contaminant transport with emphasis on better understanding the nature of organic contaminant interactions with subsurface solids. Donald P. Durfee received his M.S. degree in environmental engineering from Johns Hopkins University in 1993 and is currently a Ph.D. student at Johns Hopkins. He is studying contaminant fate and transport in the subsurface and is also interested in site characterization and remediation issues. Ryan D. Wilson is a research associate and Ph.D. student in the Department of Earth Sciences at the University of Waterloo Waterloo Ontario. His research interests include field and modeling studies of semipassive remediation technologies and the behavior of gaseous tracers. Wilson received his B.Sc. in geology from the University of Alberta in 1987 and his M.Sc. in earth sciences (hydrogeology) from the University of Waterloo in 1993. Michael J. Br

The evaluation of contaminant concentrations in ground water and soil is an essential aspect of most hazardous waste remedial investigations. This paper describes methods applied toward obtaining, preserving, and analyzing subsurface samples for the determination of VOC concentrations in the saturated region of an unconfined coastal plain aquifer at Dover Air Force Base (DAFB), Delaware. The described protocol involved headspace-free subsampling of cores, field preservation of subsamples in methanol, and overnight extraction of the VOCs at elevated temperature (70 degrees C). Methanol-extracted compounds were subsequently transferred to hexane and analyzed by gas chromatography. The method was found to achieve quantitative extraction from the aquifer sands in a single step, although extraction from fine-grained and more strongly sorbing aquitard samples required multiple methanol extractions to achieve comparable recovery. An extensive set of DAFB results is presented as an indication of how these methods can be applied toward characterizing field-scale contamination with a high degree of resolution and accuracy. These data have enabled a quantitative estimate of the contaminant distribution at this site and offer valuable insight into processes of contaminant migration into the underlying aquitard. In these regards, the methods used are believed to have provided much more accurate results than could have been obtained using more commonly applied techniques.

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Developing a prototype concurrent design tool for composite topside structures

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NAVAL ENGINEERS JOURNAL 1997年第3期109卷 279-290页

作者： Dirlik, S Hambric, S Azarm, S Marquardt, M Hellman, A Bartlett, S Castelli, V Steve Dirlik:began his career at the Naval Surface Warfare Center Carderock Division in 1981 as an aerospace engineer co-op student. He completed his bachelor of science degree in aeropace and ocean engineering from Virginia Polytechnic Institute and State University in 1985 and his master of science degree in aerospace engineering from the University of Maryland in 1990. Mr. Dirlik recently completed a master of science program in applied physics at The Johns Hopins University and currently works in the Radar Cross Section and Target Physics Branch of the Signatures Directorate at the Naval Surface Warfare Center Corderoke Division. He has worked on Navy low observable programs since 1990. Stephen Hambric:is a research associate at the Applied Research Laboratory at The Pennsylvania State University. He received his B. S. and M.S. degree in mechanical engineering from Virginia Polytechnic Institute and State University and his D. Sc. in mechnical engineering from the George Washington University. He has worked on several computer aided multidiscikplinary design and optimization projects over the years including an automated propeller design system and a structural acoustic optimization capability. Dr. Shpour Azarm:is currently working as an associate professor with the Design and Manufacturing Group of the Department of Mechanical Engineering at the University of maryland at College Park. Dr Azarm's expertise is in the areas of optimization-based designed and concurrent design and optimization of multidisciplinary systems. He was a consultant at Black & Decker Corporation (summer 1996) and worked as a Navy senior summer faculty fellow (summer 1995) and a NASA summer faculty fellow (summer 1994). He was a visiting scientist at NASA Langley Research Center for Multidisciplinary Analysis and Applied Structural Optimzatiom at the University of Siegen in Germany (spring 1992) and the Design Institute of the Technical University of Denmark (summer 1990). Dr Azarm was an associate technical editor of the ASME Jour

A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent engineering of Layered Structures, provides designers with an immediate assessment of the impacts of their decisions on several disciplines which are important to the performance of a modern naval topside structure, including electromagnetic interference effects (EMI), radar cross section (RCS), structural integrity, cost, and weight. Preliminary analysis modules in each of these disciplines are integrated to operate from a common set of design variables and a common materials database. Performance in each discipline and an overall fitness function for the concept are then evaluated. A graphical user interface (GUI) is used to define requirements and to display the results from the technical analysis modules. Optimization techniques, including feasible sequential quadratic programming (FSQP) and exhaustive search are used to modify the design variables to satisfy all requirements simultaneously. The development of this tool, the technical modules, and their integration are discussed noting the decisions and compromises required to develop and integrate the modules into a prototype conceptual design tool.

关键词： Warships

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Operational systems, logistics engineering and technology insertion

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NAVAL ENGINEERS JOURNAL 1997年第3期109卷 205-220页

作者： Grubb, MJ Skolnick, A Michael J. Grubb:has perfomzed naval engineering at the Crane Division Naval Surface Warfare Center (NSWC) for more than twenty-five years. He currently the program manager for the Sustainable Hardware and Affordable Readiness Practice Program (SHARP). is a Navy-wide logistics research and development prgram aimed at the successful transiton of proved technologies inot the fleet. SHARP focuses on reducing acquisition performance capability reliability maintainability and readiness of these systems. Mr. Grubb has served as a department director for the past eleven years. His most recent assignment was as director of the Tactical Computer Resources and Test Equipment Department. This organization provided acquisition and in-service engineering support of the Navy's tectical embedded computers priphirals displays and mass memory storage devices. The organization also provided a complete range of product engineering and metrology engineerig services for SSP NevSeaSysCom and the Trident Program. Prior to this appointment Mr. Grubb was deptuy director psysical security programs department and site responsible for program management and system integration of ashore integrated security systems. Mr. Grubb holds a B.S. degree in industrial engineering from Iowa State Universtiy an M.S. degree in industrial engineering from Purdue University and has copleted the course work (Dec.'96 for a master's degree in public and environment affairs at Indiana University-Purdue Univeristy Indianapolis. Dr. Alfred Skolnick operates System Science Consultants (SSC) specilizing in strategic planning technical program definiton technology assessment and engineering analyses on selected matters of national interest. He has taught physics mathematics and management sciences at University of Virginia and Marymount University and is currently adjunct professor of mathematics at Northern Virginia Community College. Form 1985 to 1989 he was president of the American Society of Noval Engineers. Dr. Skolnick served at Applied Physic

In an era of fiscal austerity, downsizing and unforgiving pressure upon human and economic capital, it is an Augean task to identify resources for fresh and creative work. The realities of the day and the practical demands of more immediate fleet needs can often dictate higher priorities. Yet, the Navy must avoid eating its seed corn. Exercising both technical insight and management foresight, the fleet, the R&D community, the Office of the Chief of Naval Operations (OpNav) and the product engineering expertise of the Naval Surface Warfare Center (NSWC) are joined and underway with integrated efforts to marry new, fully demonstrated technologies and operational urgencies. Defense funding today cannot sponsor all work that can be mission-justified over the long term because budgets are insufficient to support product maturation within the classical development cycle. However, by rigorous technical filtering and astute engineering of both marketplace capabilities and currently available components, it is possible in a few select cases to compress and, in effect, integrate advanced development (6.3), engineering development (6.4), weapon procurement (WPN), ship construction (SCN), operation and maintenance (O&M,N) budgetary categories when fleet criticalities and technology opportunities can happily meet. In short, 6.3 funds can be applied directly to ''ripe gateways'' so modern technology is inserted into existing troubled or aging systems, sidestepping the lengthy, traditional development cycle and accelerating practical payoffs to recurrent fleet problems. To produce such constructive results has required a remarkable convergence of sponsor prescience and engineering workforce excellence. The paper describes, extensively, the philosophy of approach, transition strategy, polling of fleet needs, technology assessment, and management team requirements. The process for culling and selecting specific candidate tasks for SHARP sponsorship (matching operational need with t

关键词： Naval vessels

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Influence of human engineering on manning levels and human performance on ships

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NAVAL ENGINEERS JOURNAL 1997年第5期109卷 67-76页

作者： Anderson, DE Oberman, FR Malone, TB Baker, CC David E. Anderson:has a bachelor of science degree in environmental engineering from Florida Technological University and a master's degree in environmental engineering from the University of Central Florida. He is a graduate of the Naval Sea Systems Command's Engineer-In-Training (EIT) Program. Mr. Anderson was instrumental in introducing the collective protection system (CPS) in the U.S. Navy developing the initial forward-fit package for the USS Gunston Hall and the engineering change proposal (ECP) for the USS Wasp. In 1990 he joined the Human Systems Integration (HSI) Division (SEA 55W5) where he was task leader for auxiliary ships. He is currently the HSI manager for the future technology variant of the SeaLift ship and the future carrier. Association of Scientists and Engineers 33rdAnnual Technical Symposium 26 April 1996. Fred R. Oberman:has B.A. and M.A. degrees from the University of Chicago and Loyola University (experimental psychology) and an M.S. degree in industrial engineering and operations research from Virginia Polytechnic Institute (VPI). He has more than 30 years experience in HSI management planning research analysis design and testing in government and private sector positions. He is currently responsible for NavSea HSI generic research and tool development efforts. He is responsible for Human Engineering Specifications and Standards (Commercial Hypertext) and is the NavSea 03D7 representative on HSI in Performance Specifications and for integration of HSI within Integrated Logistic Support (ILS). He has served as DoD HSI SubTAG chair and member of the Simulation and Modeling Test and Evaluation Display and Control Systems Human Computer Interaction Specifications and Standards and Systems Design Sub Tags as a member of the Society of Naval Architects and Marine Engineers (SNAME) Systems Safety Panel and a member of NATO RSG 14 on man-machine analysis. Thomas B. Malone: CHFEP received a Ph.D. in experimental psychology from Fordham University in 1964. He is president of Carlow

The objectives of Human engineering (HE) are generally viewed as increasing human performance, reducing human error, enhancing personnel and equipment safety, and reducing training and related personnel costs. There are other benefits that are thoroughly consistent with the direction of the Navy of the future, chief among these is reduction of required numbers of personnel to operate and maintain Navy ships. The Naval Research Advisory Committee (NRAC) report on Man-Machine Technology in the Navy estimated that one of the benefits from increased application of man-machine technology to Navy ship design is personnel reduction as well as improving system availability, effectiveness, and safety The objective of this paper is to discuss aspects of the human engineering design of ships and systems that affect manning requirements, and impact human-performance and safety The paper will also discuss how the application of human engineering leads to improved performance, and crew safety, and reduced workload, all of which influence manning levels. Finally, the paper presents a discussion of tools and case studies of good human engineering design practices which reduce manning.

关键词： Human engineering

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Null-additive fuzzy measures on S-compact spaces

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INTERNATIONAL JOURNAL OF GENERAL systems 1996年第3期25卷 219-228页

作者： Jiang, QS Klir, GJ Wang, ZY On leave from Department of Mathematics Chiba Institute of Technology Shibazono Narashino 275 Japan Department of Systems Science and Industrial Engineering Thomas J. Watson School of Engineering and Applied Science State University of New York at Binghamton Binghamton New York 13902-6000 U.S.A. Department of Systems Science and Industrial Engineering Thomas J. Watson School of Engineering and Applied Science State University of New York at Binghamton Binghamton New York 13902-6000 U.S.A.

In this paper, a further research on structural characteristics of fuzzy measures on S-compact spaces is made. The relations among the null-additivity, pseudometric generating property and autocontinuity are depicted ... 详细信息

关键词： S-compact spaces fuzzy measures null-additivity autocontinuity exhaustivity pseudometric generating property

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Some possible new applications of a partial-discharge (PD) model and its relation to PD-detection sensitivity

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EUROPEAN TRANSACTIONS ON ELECTRICAL POWER 1996年第6期6卷 445-448页

作者： Danikas, MG [?]Dr. Michael Danikas (1957) received the B. Sc. in Electrical and Electronic Engineering from the University of Newcastle-upon-Tynel England the M. Sc. from the same University and the Ph. D. from Queen Mary College University of Londod England in 1980. 1982 and 1985 respectively. He is presently Assistant mfessor at Democritus University of Thnce/Greece Department of Electrical and Computer Engineering. His research interests are mechanism of partial discharges composite insulating systems under high electrical and thermal stresses polymer outdoor insulation insulating materials at very low temperatures and breakdown mechanism in insulating liquids. (Democritus University of Thrace. Department of Ekctrical anti Computer Engineering Electric Energy Systems Laboratory. GR-67100 Xanthi/Greece T +30541/79979 Fax +30-541127954.

In this paper some possibilities of further applications of a known ''Streamer Partial-Discharge Model'' are proposed. These possibilities refer to the relation between the observed partial-discharge (PD) magnitude and the applied field to the insulation. Furthermore, the model is a useful tool to investigate the sensitivity of a PD detector and also to compare the sensitivities between various PD detectors.

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Adaptive synchronization of Chua's oscillators

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INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS 1996年第1期6卷 189-201页

作者： Chua, LO Yang, T Zhong, GQ Wu, CW Electronics Research Laboratory Department of Electrical Engineering and Computer Sciences University of California at Berkeley Berkeley CA 94720 USA Visiting scholar on leave from the Department of Automatic Control Engineering Shanghai University of Technology 149 Yan Chang Road Shanghai 200072 P. R. China. Visiting scholar on leave from Guangzhou Institute of Electronic Technology Academia Sinica Guangzhou 510070 P. R. China.

In this letter, we study the use of adaptive controllers to maintain the synchronization of two Chua's oscillators when the channel and circuit parameters are time-varying. We present both computer simulation resu...

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Reliability evaluation of highly reliable computer control systems for energy generation, transmission and distribution

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EUROPEAN TRANSACTIONS ON ELECTRICAL POWER 1996年第2期6卷 111-118页

作者： Kochs, HD Dieterle, W Dittmar, E [?]Prof. Dr.-Ing. Hans-Dieter Kochs (1943) VDE is head of the Department of Computer Science and Information Processing Systems at the Gerhard Mercator-University of Duisburgl Germany. He received the Dip1.-Ing. degree in Electrical Engineering and the Dr.-Ing. degree from the RWTH Aached Germany in 1972 and 1976 respectively. From 1979 to 1991 he was system engineer and division leader in the areas of R & D of highly-reliable large-scale control and information systems (AEGIDaimler FAG-Kugelfischer). Since 199 1 he has been Professor at the University of Duisburg. His current R & D areas are reliability safety and fault tolerance of technical systems especially automation systems and hybridknowledge based systems including fuzzy-logic and neural networks. (Gerhard-Menxitor-University-GH Duisburg FB 71FG 10 Lotharstr. 1 D-47048 Duisburg T +49203/379-2204 Fax +49203I379-2205)

The paper presents the results of an application-based reliability study of distributed computer control systems with very high reliability demand, e.g. for supervision and control of power plants and energy distribution systems. A reliability classification scheme is presented and typical redundant control system structures are evaluated and classified due to their system reliability Special focus is placed on assessing the influence of the communication system on total system reliability.

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Soliton system evaluations using fibers with dispersion and loss fluctuations

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第4期79卷 77-84页

作者： Ishiba, K Komatsu, T Takahara, M Faculty of Engineering Yamanashi University Kofu Japan 400 Graduated in 1994 from the Department of Electronic and Information Engineering where he is currently in the Master's program. He has been engaged in research on optical fiber soliton transmission. Received his B.S. and M.S. degrees in 1993 and 1995 respectively from the Department of Electronic and Information Engineering Yamanashi University. He joined NTT in April 1995. He has been engaged in research on simulation of the optical fiber soliton transmission and on the transmission system with flexibility in transmission speed. Graduated from the Department of Electrical Engineering Yamanashi University in 1965 and received his M.S. degree in 1967. He received his Ph.D. degree later. In 1967 he became a Research Associate of the Department of Electronic Engineering Yamanashi University. In 1991 he became a Professor of Electronic and Information Engineering. He has been engaged in research on special function theory nonlinear circuits optical communication systems and LAN systems. In 1984 he received a Book Award from I.E.I.C.E. In 1990–91 he was on leave at Southampton University. He is a member of IEEE.

In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity system. Several long-distance transmission experiments for high-density transmission by wavelength demultiplexing method (WDM) have been reported recently. However, more of the experimental examples have reported on soliton transmission than on WDM systems. Hence, the former is considered more advanced. It is necessary to prepare a fiber of a length of approximately 10,000 km for ultralong-distance transmission experiment. Since this is difficult to obtain, repetitive experiments are often the case. However, such an experiment does not disclose the effects of dispersion and loss fluctuation in the fiber. In this paper, the effect of fluctuation in dispersion and loss in the fiber is studied by simulation so that the resilience of the soliton to the variations of the fiber characteristics is evaluated.

关键词： optical soliton dispersion fluctuation loss fluctuation Gordon-Haus jitter

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Fast and accurate method to measure interharmonics in power systems

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EUROPEAN TRANSACTIONS ON ELECTRICAL POWER 1996年第3期6卷 169-174页

作者： Dai, X Gretsch, R [?]Associate Prof. Dr.-Ing. Xianzhong Dai (1954) received the Dr. degree (Elec. Eng.) from Tsinghua University of China in 1986. In 1988 he joined Southeast University as Associate Professor. In 1991 he became Humboldt Research Fellow and worked for two years at University of Erlangen-Nurnberg/Germany. His research work is focused to real-time control measurement and computer application on reactive power and harmonics compensation in power systems. (Automatic Control Engineering Department Southeast University Nanjing Jiangsu P. R. China)

In order to improve the resolution of spectrum analysis, the traditional method is to take more sampling periods, e. g. 50 sampling periods corresponding to the spectrum interval of I Hz. This method is not suitable to the interharmonic measurement, because most interharmonics vary rather quickly with the time and so the analysis results based on long time sampling may be useless. In this paper the zero-padding technique with short sampling time is used to resolve interharmonics, and the zoom FFT is used to decrease the computation time in order to meet the needs of real-time measurement. The simulating computation shows that the resolution for two adjacent frequency components is usually sufficient to measure harmonics and interharmonics in power systems with acceptable short sampling and computation time. This method is also suited to analyse harmonics and interharmonics when there exists an undesirable asynchronous deviation between the sampling period and the signal period.

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