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

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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Interactive tools for signal processing education. The signal processing instructional facility (SPIF lab) at Washington State University

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computer applications in engineering Education 1993年第6期1卷 517-517页

作者： Bamberger, R.H. Signal Processing Instructional Facility School of Electrical Engineering and Computer Science Washington State University Pullman WA 99164-2752 Dr. Roberto H. Bamberger:was born on January 30 1965 in Buenos Aires Argentina. He received his B.E.E and PhD from the Georgia Institute of Technology in 1986 and 1990 respectively. Currently Dr. Bamberger is an assistant professor in the School of Electrical Engineering and Computer Science at Washington State University. Dr. Bamberger's research program is focused on the design implementation and application of multidimensional multirate filter banks subband image and video compression analysis of nonstationary data and application of digital signal processing techniques in the design of analog and mixed-mode integrated circuits. Dr. Bamberger is the founder and director of the Signal Processing Instructional Facility (SPIF Lab) at Washington State University. The SPIF Lab features interactive multimedia-based tools for teaching concepts related to linear systems theory. Dr. Bamberger is active in developing multimedia-based instructional laboratories for a variety of other topics as well. In addition to his teaching and research programs Dr. Bamberger is an associate editor for theIEEE Transactions on Signal Processingand a member of the editorial board forComputer Applications in Engineering Education. Dr. Bamberger is also advisor to the WSU Student Branch of the IEEE and assistant director of the WSU Cougar Marching Band. Dr. Bamberger is a member of Phi Eta Sigma Eta Kappa Nu Tau Beta Pi and Kappa Kappa Psi.

The Signal Processing Instructional Facility (SPIF Lab) is an experiment in using in interactive multimedia for teaching concepts related to linear systems theory and signal processing. The goals of the SPIF lab are to augment, enhance, and interconnect sophomore, junior, and senior level courses with the common thread of linear systems and transforms by unifying the experimentation medium. In this fashion, physical phenomenon is returned to the forefront of engineering education. The laboratory features powerful Mathematica Notebooks (a form of hypertext) and interactive applications that use dedicated DSP microprocessors.

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CONCURRENT BOUNDARY-ELEMENT COMPUTATION

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INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1993年第2期6卷 83-98页

作者： MCDOWALL, DS LEE, TW FUSCO, VF Microwave Research Group Department of Electrical and Electronic Engineering The Queen's University of Belfast Ashby Building Stranmillis Road Belfast BT9 5AH Northern Ireland U.K. D. Stewart McDowall was born in Dublin epublic of Ireland in 1967. He received the M. Eng. degree in Electrical and Electronic Engineering from the Queen's University of Belfast in 1990. In the same year he was presented with a Distinction Award from the Department of Education of Northern Ireland and he is currently pursuing his Ph.D. in the Microwave Research Group at Q.U.B. His principal research area is the electromagnetic field mapping of microwave systems using concurrient programming. He is an Associate Member of the Institute of Electrical Engineers. Lee Thaim Wee was awarded the degree of B. Eng. in Electronics from the Queen's University of Belfast in July 1991. He is currently serving in the Malaysian Armed Forces. Vincent F. Fusco was educated at the Queen's Univeristy of Belfast where he obtained the degree of Ph.D. in 1982. He has worked as a research engineer on short-range radar and radio telementry systems. Currently he is a reader in Microwave Communications in the School of Electrical Engineering and Computer Science the Queen's Univeristy of Belfast. His current research interests include non-linear microwave circuit simulation and concurrent programming techniques for electromagnetic field problems with particular emphasis on EMC applications. He has published numerous research papers in these areas. He is the author of the bookMicrowave Circuits Analysis and Computer Aided Design Prentice-Hall 1987. Dr Fusco is a Chartered Electrical Engineer and a Member of the Institute of Electrical Engineers.

A major limitation of the boundary element method (BEM) for the solution of electrical potential problems is the long computational time required. However, a large portion of the calculations involved can be viewed as being parallel in nature and can therefore be computed concurrently. This paper makes an effort to increase the efficiency of the BEM process using transputer-based multiprocessor computing techniques. The algorithms developed may equally well be applied to any multiprocessor system. The application selected to demonstrate the technique is the solution of an electrostatic problem governed by a two-dimensional Laplace equation. A parallel algorithm for problem setup and field extraction using BEM is designed and implemented on a transputer array. Special attention is directed to the utilization of the parallel processors to achieve maximum efficiency. The analysis in this work concentrates on the communication strategies for passing data between processors as well as a consideration of the workload attributed to each processor. The parallel algorithms were implemented using 3L Parallel Fortran;however, the choice of topology for the overall BEM implementation was limited by the fact that certain parts of the algorithm could only utilize a pipeline configuration of processors. Comprehensive results for the parallel BEM algorithm are given and they are encouraging, indicating that parallel processing has much to offer when applied to the boundary element method.

关键词： Boundary element method

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STATISTICAL PROCESS-CONTROL FOR SOFTWARE IN THE MAINTENANCE PHASE

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NAVAL ENGINEERS JOURNAL 1993年第3期105卷 192-200页

作者： LUKE, SR JACOBS, DA REED, BM Stephen R. Luke:is a registered professional engineer in the Commonwealth of Virginia. He received his B.S. in mechanical engineering from Virginia Polytechnic Institute in 1983 and is presently pursuing a master's degree in engineering management at Old Dominion University. Mr. Luke is experienced as a test engineer at the Norfolk Naval Shipyard (1978–1989) and as a reliability/quality engineer at the Naval Undersea Warfare Center Detachment Norfolk (1989-Present). Currently he is the group leader of the RMA/QA group for the AN/SQQ-89(V) Antisubmarine Warfare System at Naval Undersea Warfare Center Detachment Norfolk. Mr. Luke is a member of ASNE IEEE (Reliability Society) and ASQC and is an ASQC certified quality engineer and reliability engineer. Derya Alasya Jacobs:is an assistant professor in the Engineering Management Department at Old Dominion University (ODU). She has a B.S. in computer science and an M.S. and Ph.D in engineering management from the University of Missouri-Rolla. Prior to joining ODU Dr. Jacobs worked as a research engineer at the Center for Technology Transfer and Economic Development at the University of Missouri-Rolla. During the same period she served as a consultant in software development for Missouri Enterprise Rolla Missouri. Dr. Jacobs' research interests are in the areas of applied artificial intelligence decision support systems operations research and computer integrated manufacturing. Billie M. Reed:is an assistant professor in the Engineering Management Department at Old Dominion University. He received a B.S. degree in mechanical engineering from Auburn University in 1971. After completing undergraduate studies Dr. Reed was commissioned as an officer in the U.S. Navy where he served in the nuclear submarine force until 1982. Following his military career Dr. Reed worked for nine years as a systems engineer and human-machine interface designer of complex interactive computer based systems for use in aircraft space and ship systems. He received his M.S. and Ph

As technology advances and our dependency on software increases, the requirement to develop the correct means to improve quality in both the deveiopment phase and the maintenance phase of software life cycle support becomes increasingly significant. The focus of this paper is on the dilemma facing software engineering in maintaining quality within the constraints of the maintenance phase. The paper further proposes that the software maintenance process can also be analvzed and improved using statistical process control (SPC) techniques. The methods discussed in this paper have been proposed for use in the Software Maintenance project at NUWC Detachment Norfolk. Upon successful testing at NUWC Detachment Norfolk, they will be forwarded to the AN/SQQ-89(V) (interagencv) Software Quality Evaluation Committee for use by other agencies which are developing and maintaining AN/SQQ-89(V) software.

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An approach to the direct analysis of transient stability

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European Transactions on Electrical Power 1993年第3期3卷 241-248页

作者： Djukanovic, M.B. Sobajic, D.J. Pao, Y.‐H. Miodrag B. Djukanovic (1959) received his B.S. M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Belgrade/Yugoslavia in 1982 1985 and 1992 respectively specializing in electric power systems. In 1984 he joined the Electrical Engineering Institute “Nikola Tesla” in Belgrade where he was working on the scientific studies in the field of power systems planning operation and control. In 1985 and 1990 he was appointed as a research scholar at the Royal Institute of Technology Stockholm and Case Western Reserve University Cleveland Ohio. His major in- terests are in the area of power system analysis steady-state and dynamic security and application of neural networks in electric power systems. (Electrical Engineering Institute “Nicola Tesla” ul. Koste Glavinica 8A YU-11000 Belgrad T +3811/2351-619 Fax + 3811/2351-823) Dejan J. Sobajic (1949) received the B.S.E.E. and the M.S.E.E. degrees from the University of Belgrade/Yugoslavia in 1972 and 1976 respectively and the Ph.D. degree from Case Western Reserve University Cleveland Ohio in 1988. At present he is with the Department of Electrical Engineering and Applied Physics Case Western Reserve University Cleveland. He is also the Engineering Manager of A1 WARE Inc. Cleveland. His current research interests include power system operation and control neuralnet systems and adaptive control. He is a member of the IEEE Task Force on Neural-Network Applications in Power Systems and of the IEEE Intelligent Controls Committee. He is the Chairman of the International Neural-Networks Society Special Interest Group on Power Engineering. (Case Western Reserve University Department of Electrial Engineering and Computer Sciences Glennan Building Ohio 44 106 USA T + 1216/421-2380 Fax +1216/368-8776) Yoh-Han Pao (1922) has been a Professor of Electrical Engineering and Computer Science at Case Westem Reserve University (CWRU) Cleveland Ohio since 1967. He has served as chairman of the University's Electrical Engineering Department

The Transient Energy Function (TEF) method has been intensely investigated over the last decade as a reliable and accurate tool for transient stability assessment of multimachine power systems. In this paper we propose the Potential Energy Boundary Surface (PEBS) based method for direct analysis of transient stability. The critical value of transient energy and the Critical Clearing Time (T_CCT) are evaluated without the need for successive calculation and memorization of the system kinetic and potential energy values along the sustained fault trajectory. The method is used for determination of output features in the training phase of the neural‐net based transient security assessment. The proposed approach is tested on the well‐known ten‐generator New England test system demonstrating the validity and accuracy of obtained results. Copyright © 1993 John Wiley & Sons, Ltd.

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A computer-controlled environmental test system for high pin-count integrated circuit packages

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Quality and Reliability engineering International 1993年第2期9卷

作者： John Barrett John Ó Donavan Thomas Hayes Seán C.Ó Mathúna National Microelectronics Research Centre University College Lee Maltings Prospect Row Cork Ireland John Ö Donavan received the B.E. (Electrical) degree from University College Cork in 1991. During 1990 and 1991 he worked with the IC Packaging Group at NMRC Ireland on computer-controlled reliability evaluation of IC packages and printed circuit boards for space applications. He is at present pursuing a postgraduate degree at NMRC Ireland on CAD for integrated circuit design as part of the JESSI CADFRAME research programme. Thomas F. Hayes received the B.E. degree in electrical engineering and the M. Eng. Sc. degree in microelectronics from University College Cork in 1987 and 1989 respectively. Since 1989 he has been working as a Research Scientist with the Interconnection and Packaging Group at NMRC Ireland. His research interests include analysis and design of the electrical parameters of high pin-count packaging and of numerical modelling of thermomechanical stresses in packaging structures. Sean Cian Ö Mathúna received the B.E. degree in electrical engineering in 1982 and the M. Eng. Sc. degree in microelectronics in 1984 both from University College Cork Ireland. He has worked in the Interconnection and Packaging Laboratory at the National Microelectronics Research Centre University College Cork Ireland since 1982. He is currently a senior research scientist within the laboratory with responsibility for IC package thermal and thermo-mechanical characterization thermal/thermo mechanical modelling and failure analysis of packaging structures. His research interests include hermetic and plastic packaging IC package performance characterization surface mount technology TAB and multi-chip module technologies environmental testing failure analysis and modelling. He is chairperson of SMART Group-Ireland a national technical support group for companies involved in surface mount and related technologies which currently has 70 member companies.

An automated environmental stress testing system, designed and assembled for testing of high pin-count integrated circuit packages and surface mount solder joint reliability is described. Details are given of the software and hardware used in the control of the environment chambers used, in monitoring of test specimen reliability parameters and in control and monitoring of special purpose integrated circuits for testing of IC package reliability. In addition, an automatic system for monitoring of the resistance of fine pitch surface mount solder joints and for detection and recording of thermally induced intermittent open circuits in these joints is described.

关键词： Environmental test Intergrated circuits IC packages solders joints Reliability

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Optimal dynamic fitting and identification of aerobomb's fitting drag coefficient curve 1

Optimal dynamic fitting and identification of aerobomb's fit...

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1st IEEE Conference on Control applications, CCA 1992

作者： Chen, Yangquan Lu, Deye Dou, Huifang Qing, Yingxiao Computer Application Research Group Dept. of Electrical Engineering Xi'in Inst. of Tech. Box 209 Xi'an710032 China Technical Support Center Baichen Proving Ground Baichen Jiling137001 China Mechatronics Research Group Dept. of Mechanical Engineering Xi'an Inst. of Tech. Xi'an710032 China PLA Lanzhou Airforce Xi'an710045 China

ISBN: (纸本)0780300475

Optimal dynamic fitting concept is proposed and applied to an aero-dynamic coefficient curve identification problem. Extracting aerobomb's optimal fitting drag coefficient curve Cdf(M) from 3-dimensional theolo-dite film data is reguarded as an optimal trucking control problem(OTCP) where Cdf(M) is control profile. From engineering application point of view, with some parametric description structure for Cdf(M), this functional minimization problem(OTCP) is converted to multivariable minimization problem. Cubic splines with deficiency 2 is employed to guarantee thecontinuity and fitting flexibility of Cdf(M). The quasi-Newton-Raphson iterative scheme is used to reduce the computational cost. The correction of initial states of trajectory eqations is discussed also. Practical test data reduction results of three bombing flight paths show that the optimal dynamic fitting concept has great applicable potentials in aerodynamic coefficient CURVE identification and in other similar application cases. The identified optimal fitting drag coefficient curve Cdf(M) can find its positive position in the applications like more accurate bombing table generation and mechanism studies about interference air flow field between aircraft and aerobombs etc.. © 1992 IEEE.

关键词： Data reduction

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Probability of error, maximum mutual information, and size minimization of neural networks

Probability of error, maximum mutual information, and size m...

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International Joint Conference on Neural Networks (IJCNN)

作者： W. Fakhr M. Kamel M.I. Elmastry VLSI Research Group Electrical and Computer Engineering Department University of Waterloo Waterloo ONT Canada PAMI Research Group System Design Engineering Department University of Waterloo Waterloo ONT Canada Waterloo Univ. Ont. Canada

An upper bound of the Bayes error probability is used as a generalization performance criterion for supervised neural network classifiers. It is shown that the maximization of the mutual information is equivalent to the minimization of this bound, and leads to a direct implementation of the Bayes framework for classification. This criterion is used both in training neural networks and in minimizing their size by adaptive pruning. A top-down heuristic for adaptively pruning nodes (weights) is proposed. The approach is applied both on probabilistic neural networks and the multilayer perceptron. Two benchmark problem results are given, verifying the validity of the approach.< >

关键词： Mutual information Neural networks Upper bound Training data Very large scale integration Error probability Parameter estimation Complex networks Adaptive systems Multi-layer neural network

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IMPROVING THE SHIP design, ACQUISITION AND CONSTRUCTION PROCESS

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

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

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

关键词： Naval Vessels

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COMPARISON OF DOWNHOLE AND SURFACE SAMPLING FOR THE DETERMINATION OF VOLATILE ORGANIC-COMPOUNDS (VOCS) IN GROUND-WATER

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GROUND WATER MONITORING AND REMEDIATION 1992年第1期12卷 126-133页

作者： ROSEN, ME PANKOW, JF GIBS, J IMBRIGIOTTA, TE Michael E. Rosen received his B.A. in chemistry from the State University of New York at Binghamton in 1981 and a Ph.D. in environmental science and engineering from the Oregon Graduate Institute in 1988. His research interests include trace environmental analysis of organic compounds. He is now manager of the Voluntary Cleanup Section of the Oregon Department of Environmental Quality (Environmental Cleanup Division 811 S.W. 6th Ave. Portland OR 97204) where he is working to develop streamlined procedures and processes for the investigation and cleanup of hazardous substance sites. James F. Pankow is professor and chairman of the Department of Environmental Science and Engineering at the Oregon Graduate Institute (Oregon Graduate Institute of Science and Technology Department of Environmental Science and Engineering 19600 N.W. von Neumann Dr. Beaverton OR 97006–1999). He received his B.A. in chemistry in 1973 from the State University of New York in Binghamton and his Ph.D. in environmental engineering science from the California Institute of Technology in Pasadena California in 1979. His group is involved in the study of the physical and chemical processes affecting the behavior of organic and inorganic chemicals in the environment. This work includes the development and application of sensitive analytical methods for the determination of trace organic contaminants in ground water systems. Jacob Gibs is an environmental engineer with the U.S. Geological Survey Water Resources Division (810 Bear Tavern Rd. Ste. 207 West Trenton NJ 08628). He received a B.S. in mechanical engineering in 1968 an M.S. in environmental engineering in 1975 and a Ph.D. in environmental engineering in 1983 all from Drexel University Philadelphia Pennsylvania. He is currently project chief of a study on representative sampling of ground water for trace levels of organic compounds. His research interests include evaluating ground water sampling techniques and devices for purgeable organic compounds design of sampling

The relative precision and accuracy of sampling and analysis methods for the determination of trace concentrations of volatile organic compounds (VOCs) in ground water were compared. Samples were collected from a well containing nanogram-per-liter (ng/L) to microgram-per-liter (mu-g/L) levels of VOCs. A Keck helical rotor submersible pump was used to collect samples at the surface for analysis by purge and trap (P&T) and for analysis by adsorption/thermal desorption (ATD). Downhole samples were collected by passing water through an ATD cartridge. Although slight spontaneous bubble outgassing occurred when the water was brought to the surface, the relative precisions and comparabilities of the surface and downhole methods were generally found to be equivalent from a statistical point of view. A main conclusion of this study is that bringing sample water to the surface for placement in VOC vials (and subsequent analysis by P&T) can be done reliably under many circumstances. However, care must still be taken to prevent adsorption losses and cross contamination. Samples subject to strong bubble outgassing will need to be handled in a special fashion (e.g., by downhole ATD) to minimize volatilization losses. Additionally, the higher sensitivity of the ATD method allows lower detection limits than are possible with P&T. For example, several compounds present at the ng/L level could be determined with confidence by ATD, but not by P&T.

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