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HYDROCARBON VAPOR DIFFUSION IN INTACT CORE SLEEVES

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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EPAS APPROACH TO VADOSE ZONE MONITORING AT RCRA FACILITIES

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GROUND WATER MONITORING AND REMEDIATION 1993年第1期13卷 151-158页

作者： DURANT, ND MYERS, VB ECCLES, LA Washington D.C. 20460) has worked as an environmental scientist in the RCRA corrective action program at EPA since 1989. After graduating from Colgate University in 1987 Durant worked for GeoTrans Inc. conducting hydrogeologic investigations at numerous waste disposal sites throughout the northeastern United States. At present Durant is pursuing an M.S. degree in environmental science from The Johns Hopkins University. His research is focused on enhancing in situ biodegradation of aromatic organic compounds in the subsurface. Washington D. C. 20460) graduated from The Johns Hopkins University in 1972 with a B.A. degree in natural sciences. Myers received a Ph.D. in oceanography from Florida State University in 1977. During 1978 he held a post doctoral fellowship at University of Florida in the Department of Environmental Engineering and Science. From 1979 to 1983 Myers was employed by the Florida Department of Environmental Regulation where he worked on environmental restoration projects. Since 1984 Myers has worked at EPA managing RCRA ground water monitoring and corrective action programs. Lawrence A. Eccles (U.S. Environmental Protection Agency Environmental Monitoring Systems Laboratory P.O. Box 93478 Las Vegas NV 89193–3478) is a hydrologist with the EPA Environmental Monitoring Systems Research Laboratory in Las Vegas Nevada. Eccles is responsible for the development of vadose zone and in situ monitoring techniques and guidelines. After graduating from Monmouth College with a B.S. degree in chemistry Eccles performed graduate work in chemical engineering at New Mexico State University. He received formal training in hydrology in 1969 from the U.S. Geological Survey in Denver and worked with that agency before joining EPA at Las Vegas in 1984. One of his co-authored articles was chosen for the Best Paper Award by the journal Ground Water in 1975 and another was the subject of a cover story for Water Well Journal in 1977.

The U.S. Environmental Protection Agency (EPA) recently proposed to amend federal regulations to require vadose zone monitoring at certain hazardous waste facilities. To support this proposal, EPA evaluated previous policy on vadose zone monitoring and examined advances in vadose zone monitoring technology. Changes in EPA vadose zone monitoring policy were driven by demonstrated advances in the available monitoring technology and improvements in understanding of vadose zone processes. When used under the appropriate conditions, currently available direct and indirect monitoring methods can effectively detect contamination that may leak from hazardous waste facilities into the vadose zone. Direct techniques examined include soil-core monitoring and soil-pore liquid monitoring. Indirect techniques examined include soil-gas monitoring, neutron moderation, complex resistivity, ground-penetrating radar, and electrical resistivity. Properly designed vadose zone monitoring networks can act as a complement to saturated zone monitoring networks at numerous hazardous waste facilities. At certain facilities, particularly those in arid climates where the saturated zone is relatively deep, effective vadose zone monitoring may allow a reduction in the scope of saturated zone monitoring programs.

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CORONA-POLED NONLINEAR POLYMERIC FILMS: IN SITU ELECTRIC FIELD MEASUREMENT, CHARACTERIZATION AND ULTRASHORT-PULSE APPLICATIONS

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Journal of Nonlinear Optical Physics & Materials 1992年第1期1卷 73-102页

作者： A. KNOESEN N.E. MOLAU D.R. YANKELEVICH M.A. MORTAZAVI A. DIENES Department of Electrical Engineering and Computer Science Organized Research Program on Polymeric Ultrathin Film Systems University of California Davis CA 95616 USA

Electric poling at field intensities approaching the dielectric strength of the film is possible with corona poling. Polymeric thin films with large second-order nonlinearities can be created with this poling technique. In this paper, the corona poling of nonlinear polymeric films at elevated temperatures, processing, characterization and possible ultrashort-pulse applications are reviewed. An experimental technique is presented to measure the electric field during poling of the nonlinear polymeric film. The characterization of orientational order in corona-poled nonlinear polymeric films and the effects associated with the large electric field during poling are discussed. Poled polymeric thin films are uniquely suited for second-order nonlinear optical applications of ultrashort pulses (< 50 fsec) since minimal pulse spreading occurs. The sum-frequency ultrashort-pulse application of nonlinear polymeric thin films and limitations of the thin polymeric films are discussed. Experimental results are presented of a side-chain nonlinear polymer that is ideally suited for ultrashort-pulse applications.

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SIMPLE APPROACH TO REFLECTANCE ANALYSIS OF BIREFRINGENT STRATIFIED FILMS

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APPLIED OPTICS 1991年第28期30卷 4017-4018页

作者： KNOESEN, A []The author is with the Department of Electrical Engineering Computer Science Organized Research Program on Polymeric Ultrathin Film Systems University of California Davis Davis California 95616

A simple analysis is presented of reflectance from a stratified uniaxial media with the optic axes parallel or perpendicular to the plane of incidence.

关键词： UNIAXIAL FILMS POLED POLYMERS THIN FILM BIREFRINGENT

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ROLE OF SIMULATION IN RAPID PROTOTYPING FOR CONCEPT DEVELOPMENT

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 204-211页

作者： KING, JF BARTON, DE J. Fred King:is the manager of the Advanced Technology Department for Unisys in Reston Virginia. He earned his Ph.D. in mathematics from the University of Houston in 1977. He has been principal investigator of research projects in knowledge engineering pattern recognition and heuristic problem-solving. Efforts include the development of a multi-temporal multispectral classifier for identifying graincrops using LANDSAT satellite imagery data for NASA. Also as a member of the research team for a NCI study with Baylor College of Medicine and NASA he helped develop techniques for detection of carcinoma using multispectral microphotometer scans of lung tissue. He established and became technical director of the AI Laboratory for Ford Aerospace where he developed expert scheduling modeling and knowledge acquisition systems for NASA. Since joining Unisys in 1985 he has led the development of object-oriented programming environments blackboard architectures data fusion techniques using neural networks and intelligent data base systems. Douglas E. Barton:is manager of Logistics Information Systems for Unisys in Reston Virginia. He earned his B.A. degree in computer science from the College of William and Mary in 1978 and did postgraduate work in London as a Drapers Company scholar. Since joining Unisys in 1981 his work has concentrated on program management and software engineering of large scale data base management systems and design and implementation of knowledge-based systems in planning and logistics. As chairman of the Logistics Data Subcommittee of the National Security Industrial Association (NSIA) he led an industry initiative which examined concepts in knowledge-based systems in military logistics. His responsibilities also include evaluation development and tailoring of software engineering standards and procedures for data base and knowledge-based systems. He is currently program manager of the Navigation Information Management System which provides support to the Fleet Ballistic Missile Progr

A valuable technique during concept development is rapid prototyping of software for key design components. This approach is particularly useful when the optimum design approach is not readily apparent or several known alternatives need to be rapidly evaluated. A problem inherent in rapid prototyping is the lack of a "target system" with which to interface. Some alternatives are to develop test driver libraries, integrate the prototype with an existing working simulator, or build one for the specific problem. This paper presents a unique approach to concept development using rapid prototyping for concept development and scenario-based simulation for concept verification. The rapid prototyping environment, derived from artificial intelligence technology, is based on a blackboard architecture. The rapid prototype simulation capability is provided through an object-oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious problem. A specific example will be discussed where this approach was used to evolve the logic of a mission controller for an autonomous underwater vehicle.

关键词： Military engineering

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computer-SYSTEM ARCHITECTURE CONCEPTS FOR FUTURE COMBAT systems

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 43-62页

作者： ZITZMAN, LH FALATKO, SM PAPACH, JL Dr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin

This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computer architecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computer architecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages and development environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination and development of a coherent multi-warfare tactical picture supporting the future combatant command st

关键词： computer Architecture

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ELECTRICALLY INDUCED TRANSMISSIVITY MODULATION IN POLYMERIC THIN-FILM FABRY-PEROT ETALONS

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APPLIED OPTICS 1989年第20期28卷 4442-4445页

作者： ELDERING, CA KOWEL, ST KNOESEN, A []The authors are with University of California Davis Department of Electrical Engineering Computer Science Organized Research Program on Polymeric Ultrathin Film Systems Davis California 95616

We report the observation of electrically induced changes in transmissivity in Fabry-Perot devices consisting of spin-cast azo-dye/polymer films deposited between gold mirrors. In poled samples the observed modulation shows a linear dependence on the applied modulating voltage. The ratio of the transmissivity modulation observed using incident transverse magnetic polarization to that observed using transverse electric polarization is used to demonstrate that the electrooptic effect dominates the modulation. This is, to our knowledge, the first reported use of a polymeric thin film linear electrooptic material in a Fabry-Perot structure and demonstrates the use of etalons to enhance electrooptic effects in very thin films.

关键词： Electrooptical effects Electrooptical modulators Materials processing Refractive index Thin film applications Thin films

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Biological image understanding

Biological image understanding

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Medical Imaging III: Image Processing 1989

作者： Dunn, Stanley M. Department of Biomedical Engineering Rutgers University P.O. Box 909 PiscatawayNJ08855-0909 United States Laboratory for Computer Science Research Rutgers University Diagnostics Systems Program New Jersey Dental School NewarkNJ United States

The primary goal of any computer vision system is to construct scene descriptions similar to those formed by the human visual system. Biological image understanding is the automatic processing and interpretation of imagery of natural structures. The key constraint is the absence of explicit models of the objects anticipated to be in the scene. A clinician interprets imagery using principles of physiology and the image acquisition process. He learns to construct explicit models to recognize patterns from these principles, but is also able to infer an interpretation of an unknown structure from examples and physiology. Our overall goal is to develop a computer vision system to be used to interpret imagery of biological data using these principles. In this paper we present a paradigm for constructing image understanding systems designed to process natural images and present some applications of the system to hematology and radiography. The first step of our general approach is data acquisition. The second step is to find intrinsic properties at each pixel. The third step is to group pixels together to for homogeneous regions using the intrinsic properties. The final step is object recognition, where object type and location are determined from the quantitative features of the homogeneous regions. We shall outline the algorithms and data structures used at each step in the process, and their implementation. We shall describe in detail a key feature of this paradigm - forming homogeneous regions by geometry guided segmentation. The fact that classical algorithms do not always yield correct results led us to an algorithm that uses structural information and intensity values to group homogeneous regions. We shall illustrate this problem and the solution, as well as preliminary results of the application of the image understanding system. © 1989 SPIE. All rights reserved.

关键词： Physiology

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THE QUANTIFICATION OF INTEROPERABILITY

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NAVAL ENGINEERS JOURNAL 1989年第3期101卷 251-256页

作者： MENSH, DR KITE, RS DARBY, PH Dennis Roy Mensh:is currently the task leader Interoperability Project with the MITRE Corporation in McLean Va. He received his B.S. and M.S. degrees in applied physics from Loyola College in Baltimore Md. and the American University in Washington D. C. He also has completed his course work towards his Ph.D. degree in computer science specializing in the fields of systems analysis and computer simulation. He has been employed by the Naval Surface Warfare Center White Oak Laboratory Silver Spring Md. for 20 years in the areas of weapon system analysis and the development of weapon systems simulations. Since 1978 he has been involved in the development of tools and methodologies that can be applied to the solution of shipboard combat system/battle force system architecture and engineering problems. Mr. Mensh is a member of ASNE MORS IEEE U.S. Naval Institute MAA and the Sigma Xi Research Society. Robert S. Kite:is a systems engineer with the Naval Warfare Systems Engineering Department of the MITRE Corporation in McLean Va. Mr. Kite received his B.S. degree in electronic engineering from The Johns Hopkins University in Baltimore Md. Mr. Kite retired from the Federal Communications Commission in 1979 and served a project manager of the J-12 Frequency Management Support Project for the Illinois Institute of Technology Research Institute in Annapolis Md. before joining MITRE. Mr. Kite is presently a member of ASNE the Military Operations Research Society and an associate member of Sigma Xi. Paul H. Darby:has worked in the field of interoperability both in the development of interoperability concepts and systems since joining the Department of the Navy in 1967. He was the Navy's program manager for the WestPacNorth TACS/ TADS and IFFN systems. He is currently head of the Interoperability Branch Warfare Systems Engineering Office Space and Naval Warfare Systems Command. He holds a B.S. from the U.S. Naval Academy.

JCS Pub 1 defines interoperability as “The ability of systems, units or forces to provide services to and accept services from other systems, units or forces and to use the services so exchanged to enable them to operate effectively together.” With JCS Pub 1 as a foundation, interoperability of systems, units or forces can be factored into a set of components that can quantify interoperability. These components are: media, languages, standards, requirements, environment, procedures, and human factors. The concept described in this paper uses these components as an analysis tool to enable specific detailed analyses of the interoperability of BFC3 systems, units, or forces for the purpose of uncovering and resolving interoperability issues and problems in the U.S. Navy, Joint, and Allied arenas. Also, as a management tool, the components can help determine potential interoperability characteristics of future U.S. Navy BFC3 systems for compliance with battle force systems architectures. The approach selected for the quantification of interoperability was the development of a set of measures of performance (MOPs) and measures of effectiveness (MOEs). The MOPs/MOEs were integrated with a candidate set of components, which were used to partition the totality of interoperability into measurable entities. The methodology described employs basic truth table theory in conjunction with logic equations to evaluate the interoperability components in terms of MOPs that were aggregated to MOEs. It is believed that this concept, although elementary and based on fundamental principles, represents an operationally significant approach rather than a theoretical approach to the quantification of interoperability. The vehicle used as a means to measure the MOPs and MOEs was the Research Evaluation and systems Analysis (RESA) computer modeling and simulation capability at the Naval Ocean systems Center (NOSC), San Diego, Calif. Data for the measurements were collected during a Tactical I

关键词： Military engineering

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THE AEGIS DATA BUS EXPERIMENT

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NAVAL ENGINEERS JOURNAL 1989年第5期101卷 53-58页

作者： FRINK, JG VERVEN, DM John G. Frink is an assistant group supervisor in the Fleet Systems Department of The Johns Hopkins University Applied Physics Laboratory. He received his B.S. degree in physics from Michigan State University in 1968 and the M.S. degree in computer science from the University of Maryland in 1971. Mr. Frink worked at the Naval Surface Weapons Center White Oak Laboratory on a variety of weapons systems before joining the Applied Physics Laboratory in 1978. Mr. Frink has supervised the development of a large scale battle group simulation that successfully employs the receiver selection paradigm described herein on a hardware suite composed of an extensible number of (currently 15) processors. David M. Verven is a senior electrical engineer in the Fleet Systems Department of The Johns Hopkins University Applied Physics Laboratory. He received the B.S. degree in electrical engineering from the University of Maryland College Park in 1979 and the M. S. degree in the same discipline from The Johns Hopkins University in 1984. Mr. Verven joined the Applied Physics Laboratory in 1979 and initially worked on analysis of Navy sensor systems. In 1981 he was the AN/SPS-49 test team leader for the New Threat Upgrade (NTU) combat system land-based test. In 1982 he became involved in the development of the BBWRS system. Currently he is involved in real-time computer program development for the CEP project.

This paper documents an experiment performed by The Johns Hopkins University Applied Physics Laboratory to measure the effect of inserting a data bus into a combat system. The experiment was conducted at the Aegis computer Center located at the Naval Surface Weapons Center in Dahlgren, Virginia (NSWC/DL). The purpose of the experiment was to determine whether or not the Aegis Weapon System (the core of the Aegis Combat System) could be operated with a portion of its point-to-point interelement cables replaced by a data bus. The data bus chosen for the experiment employs message broadcasting with receiver selection. A primary goal of the experiment was to minimize the amount of Aegis computer program changes required to accommodate the data bus. The results presented in this paper will show that the experiment was a success. Key certification tests were passed with no computer program changes to the tactical elements and minimal changes in the Aegis tactical executive (ATES) program (less than 110 words changed).

关键词： Data Transmission Equipment

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