Summary of Engineering Research Preview

The 2001 Summary of Engineering Research is on the Web and available on CD-ROM by request. Published since the early 1900s, this resource offers program descriptions, project summaries, and publication lists that represent the research efforts of College of Engineering faculty during the calendar year 2000.

The research program, a more than $160-million endeavor, involves some 650 researchers as well as numerous graduate and undergraduate students working on projects directed by engineering faculty. More than 1,600 projects are under way and nearly 3,000 publications are reported. Following is just a sampling of projects researchers reported in 2001. (Principal investigators are designated with an asterisk.)

Silicon-Germanium Modulation-doped Field Effect Transistors

I. Adesida,* K. Ismail*

National Science Foundation, ECS 97-10418 (In cooperation with the Microelectronics Laboratory)

This collaborative program with IBM Corp. is intended to significantly advance the growth and fabrication technologies for SiGe/Si modulation-doped field effect transistors (MODFETs) needed for low-power, high-speed microwave and digital applications. Specific goals are to study the physics of short gate-length p-type, n-type, and complementary MODFETs and to demonstrate simple circuits.

Advancing the Performance-Based Seismic Design of Buildings

M. Aschheim,* I. Cuesta

National Science Foundation CAREER Award

This work will develop and validate simple techniques for the performance-based seismic design and rehabilitation of multistory buildings. Design techniques will utilize Yield Point Spectra, a variant of the Capacity Spectrum Method. Simple graphical techniques for determining combinations of strength and stiffness to achieve arbitrary performance objectives will be validated. Various strategies for addressing higher modes in design will be investigated to determine those for which response amplitudes are predicted well using a single mode analogy. Advanced multivariate statistical techniques will be applied to identify mode shapes in the results obtained from nonlinear dynamic analyses. Improved techniques for estimating peak interstory drifts will be evaluated. A laboratory module will be developed for use by the 22 undergraduate institutions nationwide that are acquiring bench-top shaking tables through the NSF CCLI program. Groups of students will design, build, instrument, and test small multistory frames. Data acquired will be postprocessed to identify fundamental response characteristics. The performance of the system as well as the utility of the design methodology will be assessed.

Building Dynamic Interoperable Security Architecture for Active Networks

R. Campbell,* M. D. Mickunas, Z. Liu, P. Naldburg, S. Yi

Defense Advanced Research Projects Agency, F30602-98-1-0192

Current active network research efforts propose novel network architectures to enable fast protocol and service deployment. However, the dynamic and proactive nature of these active networks increases the malicious usage of the networks. There is little research into the nature of the security provisions. Researchers working on this project believe that the security architecture should be dynamic, reconfigurable, extensible, and interoperable. The active security architecture supports dynamic security policies interoperability among different security domains, active capabilities providing application-specific security functions, and defense against distributed denial of science attacks.

Hysteresis, Noise, and Domain Wall Dynamics in Systems Ranging from Magnets to Earthquakes

K. A. Dahmen*

National Science Foundation, NSF DMR99-72783/66 (In cooperation with the NFS-funded Materials Computation Center and the Frederick Seitz Materials Research Laboratory)

Magnets, earthquake faults, and many other systems respond to slowly changing external conditions with discrete, impulsive events that span a huge range of sizes (Barkhausen noise or avalanches in the case of magnets, and earthquakes in the case of the earth). Researchers study Barkhausen noise in disordered magnets as a representative of these systems and compute predictions for the universal aspects of the behavior on long-length scales as a function of disorder, field sweep rate, history, and temperature. This research uses ideas from phase transitions, the renormalization group, and disordered systems theory.

The "Quick Fiber" Process to Enhance Dry-Grind Ethanol Profitability

S. R. Eckhoff,* K. D. Rausch, V. Singh, A. McAloon

Illinois Corn Marketing Board; Illinois Council on Food and Agricultural Research External Competitive Grants Program; Council of Great Lakes Governors; Illinois Biomass Energy Program

The "quick fiber" process recovers pericarp fiber from degerminated corn for use in dry-grind ethanol facilities. Optimal operating conditions are used to recover fiber and to determine the economic benefits to dry-grind ethanol producers removing the fiber. Preliminary analysis indicated approximately a $0.04 per gallon ($0.10 per bushel) advantage of the quick fiber process. Most of the economic benefit is from increased capacity in the fermentors. The fiber has also been shown to contain significant levels of cholesterol-lowering ferulate esters.

Real-Time Security Monitoring and Control

G. Gross*

National Science Foundation

Researchers have prepared a White Paper that outlines the scope of issues, challenges, and opportunities in the area of real-time security monitoring and control (RTSMC) of power systems in the restructured electricity industry. The counterpart of power system reliability in real-time operations is security—the ability of the power system to withstand contingencies. This White Paper is part of a set of six papers on reliability aspects of the electric power system prepared for the U.S. Department of Energy by the Consortium of Electric Reliability Technology Solutions (CERTS).

Theory of Compositional Ordering in Ternary Metallic Alloys

D. D. Johnson*

U.S. Department of Energy, DE-FG02-96ER45439 (In cooperation with the Frederick Seitz Materials Research Laboratory and Sandia National Laboratories)

The degree to which ordering (chemical and magnetic) exists in high-temperature alloys can be probed by diffuse scattering experiments. Researchers develop and apply a first-principles theory of alloys to compare directly and explain experimental data based on the underlying electronic and magnetic interactions. For the first time, the results of the scattering experiments can be related directly to the electronic structure of metallic alloys, thereby elucidating the microscopic reasons for the structural ordering and providing valuable guidance in the design of new and improved alloys. This represents a significant advance in alloy theory.

Dynamics of Phase Inversion Related to Drug Delivery

A. J. McHugh,* J. R. DesNoyer, K. J. Brodbeck

National Science Foundation, CTS 97-31509; Alza Corp.

The principles of phase inversion are being applied in studies of injectable drug delivery systems consisting of a water-insoluble polymer, biocompatible solvent, and bioactive agent. In situ optical measurement techniques are used to quantify the interaction of liquid demixing, gelation, and drug release rates in solutions quenched into an aqueous environment. Water influx rates and bath-side mass transfer dynamics are correlated with the drug release rate and morphology of the formed gel. Systems under study include poly (lactide-co-glycolide) (PLGA) copolymers of various molecular weights and composition, a variety of biocompatible solvent systems, and model protein systems such as chicken egg lysozyme.

Turbulence Simulation for Solid-Rocket Applications

R. D. Moser,* R. J. Adrian, S. Balachandar, P. Venugopal, F. Najjar, Z. Deng

U.S. Department of Energy, Center for Simulation of Advanced Rockets

New large-eddy simulation (LES) model and simulation techniques are being developed for use in the simulation of solid-rocket motors. Solid-rocket flows present interesting challenges to turbulence simulation, including large transpiration, combustion, large-temperature and density variations, and burning particles. These complications will be treated using the optimum LES modeling technique based on stochastic estimation.

Neural Control, Active Sensing, and Sensorimotor Integration in Hexapod Robots

M. Nelson,* N. Ahuja*

U.S. Office of Naval Research, N00014-96-1-0657 (Conducted in the Beckman Institute for Advanced Science and Technology)

The overall goal of this research project is to design, construct, and evaluate integrated active sensing and motor control systems for legged robots using insights provided by insect neurobiology. Researchers are developing neurally inspired control systems for insect-like robots that incorporate mechanosensory signals from leg sensors and visual signals from an active vision system to carry out visually guided behavior in complex environments that may include obstacles and irregular terrain. The biological basis for this work is provided by a large body of anatomical, physiological, and behavioral studies of cockroaches, walking sticks, crickets, locusts, and mantids.

Integrated Mesoscopic Cooler Circuits (IMCCs): A Transforming Technology of Robust Ultraefficient Environmental Control for Warriors of the 21st Century

M. L. Philpott,* M. A. Shannon,* J. Economy, A. A. Rockett, C. W. Bullard, A. M. Jacobi, T. A. DeTemple, D. J. Beebe, K. C. Hsieh, N. R. Miller, H. Sehitoglu, P. S. Hrnjak, M. T. A. Saif, N. Aluru

Defense Advanced Research Projects Agency

A system of lightweight micro-coolers is being developed by combining new layered mesoscopic fabrication techniques with a scale-efficient vapor-compression cycle. A network of compliant electrically powered devices approximately 120 mm (4.7 in.) square and 3 mm (< 1/8 in.) thick are meshed together to form an active cooling fabric. The mesoscopic processes under development combine polyimide/thin-film layering technologies with silicon-based electromechanical device fabrication. An important potential application is the cooling of military personnel on active duty in hot climates. Other potential applications include cooling of microelectronics and infrared sensors and weapon systems that can benefit from robust distributed cooling.

An Integrated Framework for Performance Engineering and Resource-Aware Compilation

C. Polychronopoulos,* W. H. Sanders, T. Huang, S. Carroll, Y. Chen, G. Clark, T. Courtney, D. Daly, D. D. Deavours, S. Derisavi, P. Kalogiannis, W. Ko, F. Koopmans, J. Lin, K. Marukawa, N. Petrovic, Q. Tian, P. Webster, Y. Wu, M. Yankelevsky, X. Zhou

National Science Foundation, EIA 99-75019 (In cooperation with the Coordinated Science Laboratory)

Design of next-generation computing and communication systems will be application-driven and will require fundamental advances in performance engineering frameworks, methods, and tools and in adaptive compilation and run-time support techniques. This work takes a systematic and synergetic approach to developing both of these capabilities and will demonstrate their use via application to several important distributed applications. In conducting the work, researchers will make fundamental advances in techniques for system and model composition, multilevel/formalism modeling and performance evaluation, adaptive compilation, and dynamic run-time support.

Context-Sensitive Natural Language Inferences

D. Roth,* A. Carlson

National Science Foundation, IIS-980163; IBM Corp.

The future of intelligent human-machine interaction is in the ability to perform context-sensitive inferences. These are knowledge intensive tasks that are difficult to make without a significant learning component. This research studies a learning approach that targets language-understanding related tasks and directly addresses the issue of scalability. Context-sensitive inferences are required at different levels of sentence processing, from word-sense disambiguation (for example, the use of the word "plant" in different contexts), to phrase interpretation (such as "move the car with the flag"). This project concentrates on the problem of context-sensitive text correction—the task of fixing spelling errors that result in valid words, such as substituting "to" for "too," "out" for "our," "now" for "know," and so on. The system is trained directly from data (sentences read from on-line newspapers) and in its current form can represent (and correct mistakes for) about 1,000 words. The approach developed can be applied to support a variety of inferences of the sort required in intelligent human-machine interactions as demonstrated in this project by developing a system that exhibits a wide coverage and accurate context-sensitive spelling correction. A demonstration of the context-sensitive text correction system is available at http://L2R.cs.uiuc.edu/~cogcomp/. This work received the American Association of Artificial Intelligence (AAAI) 2001 Innovative Applications of AI Award.

3-D Influence Correction Scheme for Application to 2-D Design

M. S. Selig,* M. D. Soso

Ford Motor Co.

Two-dimensional airfoils designed for racecar applications undergo significant performance changes when their low aspect ratio, 3-D counterparts are used in the real situation. To compensate for these changes, endplates are attached to both ends of the wings. Research is being carried out to develop a 3-D influence correction scheme that incorporates the effective aspect ratio of the endplates into the initial 2-D airfoil design. This should allow closer matching of the initial design characteristics with the final product.

Characterization of Scales in the Chicago Water Distribution System

V. L. Snoeyink,* P. Sarin, D. Frommell, W. Kriven

City of Chicago, Ill.

The objective of this project is to determine the chemical composition of scales that have been found on cement- and mortar-lined distribution pipes and to determine ways to control the formation of this scale. The approach involves use of energy dispersive spectroscopy to determine elemental composition and nuclear magnetic resonance spectroscopy to determine chemical structure. A pipe-loop system with lead pipe harvested from the Chicago system is being used to show the impact of any changes in aluminum concentration and phosphate dose on lead release.

Development of Virtual Prototyping Systems

R. S. Sreenivas,* W. R. Norris

Caterpillar, Inc.

The notion of "steering quality" is difficult to quantify in the design of steering systems for earth-moving vehicles. Researchers envision an expert driver operating a simulated vehicle within a virtual environment where the parameters in the design of a steering system can be altered instantaneously. In this paradigm, the process of trial-and-error design becomes a viable option. This project involves the derivation of vehicle models of appropriate complexity and detail that can be simulated in real-time within a virtual environment. To improve the real-time performance of these models, particular attention is focused on artificial neural networks.

Characterizing Dual Magnetic Resonance Imaging and Boron Neutron Capture Therapy Reagents

E. Wiener,* N. Pederson

National Institutes of Health, PHS 2P41 RR 05964-06

Neutron capture therapy (NCT) is a binary technique that delivers a nonradioactive agent to the tumor followed by neutron irradiation and conversion of the agent into a radioactive compound. To predict the efficacy of the treatment, one must run dosimetric calculations. This implies an a priori knowledge of the drug concentration. One technique uses a method based on the tumor enhancement achieved with gadolinium labeled derivatives and magnetic resonance imaging (MRI). This requires an understanding of the magnetic properties of the agents under physiological conditions. The focus of this research is on characterizing a gadolinium-labeled carbon derivative for dual MRI and NCt applications.

Look for a link to the 2001 Summary of Engineering Research on the "Research" area of the College of Engineering website, http//:www.engr.uiuc.edu/. Inquiries about the CD-ROM or engineering research at the University of Illinois may be sent to Summary of Engineering Research .	The 2001 Summary of Engineering Research is on the Web and available on CD-ROM by request. Published since the early 1900s, this resource offers program descriptions, project summaries, and publication lists that represent the research efforts of College of Engineering faculty during the calendar year 2000. The research program, a more than $160-million endeavor, involves some 650 researchers as well as numerous graduate and undergraduate students working on projects directed by engineering faculty. More than 1,600 projects are under way and nearly 3,000 publications are reported. Following is just a sampling of projects researchers reported in 2001. (Principal investigators are designated with an asterisk.) Silicon-Germanium Modulation-doped Field Effect Transistors I. Adesida,* K. Ismail* National Science Foundation, ECS 97-10418 (In cooperation with the Microelectronics Laboratory) This collaborative program with IBM Corp. is intended to significantly advance the growth and fabrication technologies for SiGe/Si modulation-doped field effect transistors (MODFETs) needed for low-power, high-speed microwave and digital applications. Specific goals are to study the physics of short gate-length p-type, n-type, and complementary MODFETs and to demonstrate simple circuits. Advancing the Performance-Based Seismic Design of Buildings M. Aschheim,* I. Cuesta National Science Foundation CAREER Award This work will develop and validate simple techniques for the performance-based seismic design and rehabilitation of multistory buildings. Design techniques will utilize Yield Point Spectra, a variant of the Capacity Spectrum Method. Simple graphical techniques for determining combinations of strength and stiffness to achieve arbitrary performance objectives will be validated. Various strategies for addressing higher modes in design will be investigated to determine those for which response amplitudes are predicted well using a single mode analogy. Advanced multivariate statistical techniques will be applied to identify mode shapes in the results obtained from nonlinear dynamic analyses. Improved techniques for estimating peak interstory drifts will be evaluated. A laboratory module will be developed for use by the 22 undergraduate institutions nationwide that are acquiring bench-top shaking tables through the NSF CCLI program. Groups of students will design, build, instrument, and test small multistory frames. Data acquired will be postprocessed to identify fundamental response characteristics. The performance of the system as well as the utility of the design methodology will be assessed. Building Dynamic Interoperable Security Architecture for Active Networks R. Campbell,* M. D. Mickunas, Z. Liu, P. Naldburg, S. Yi Defense Advanced Research Projects Agency, F30602-98-1-0192 Current active network research efforts propose novel network architectures to enable fast protocol and service deployment. However, the dynamic and proactive nature of these active networks increases the malicious usage of the networks. There is little research into the nature of the security provisions. Researchers working on this project believe that the security architecture should be dynamic, reconfigurable, extensible, and interoperable. The active security architecture supports dynamic security policies interoperability among different security domains, active capabilities providing application-specific security functions, and defense against distributed denial of science attacks. Hysteresis, Noise, and Domain Wall Dynamics in Systems Ranging from Magnets to Earthquakes K. A. Dahmen* National Science Foundation, NSF DMR99-72783/66 (In cooperation with the NFS-funded Materials Computation Center and the Frederick Seitz Materials Research Laboratory) Magnets, earthquake faults, and many other systems respond to slowly changing external conditions with discrete, impulsive events that span a huge range of sizes (Barkhausen noise or avalanches in the case of magnets, and earthquakes in the case of the earth). Researchers study Barkhausen noise in disordered magnets as a representative of these systems and compute predictions for the universal aspects of the behavior on long-length scales as a function of disorder, field sweep rate, history, and temperature. This research uses ideas from phase transitions, the renormalization group, and disordered systems theory. The "Quick Fiber" Process to Enhance Dry-Grind Ethanol Profitability S. R. Eckhoff,* K. D. Rausch, V. Singh, A. McAloon Illinois Corn Marketing Board; Illinois Council on Food and Agricultural Research External Competitive Grants Program; Council of Great Lakes Governors; Illinois Biomass Energy Program The "quick fiber" process recovers pericarp fiber from degerminated corn for use in dry-grind ethanol facilities. Optimal operating conditions are used to recover fiber and to determine the economic benefits to dry-grind ethanol producers removing the fiber. Preliminary analysis indicated approximately a $0.04 per gallon ($0.10 per bushel) advantage of the quick fiber process. Most of the economic benefit is from increased capacity in the fermentors. The fiber has also been shown to contain significant levels of cholesterol-lowering ferulate esters. Real-Time Security Monitoring and Control G. Gross* National Science Foundation Researchers have prepared a White Paper that outlines the scope of issues, challenges, and opportunities in the area of real-time security monitoring and control (RTSMC) of power systems in the restructured electricity industry. The counterpart of power system reliability in real-time operations is security—the ability of the power system to withstand contingencies. This White Paper is part of a set of six papers on reliability aspects of the electric power system prepared for the U.S. Department of Energy by the Consortium of Electric Reliability Technology Solutions (CERTS). Theory of Compositional Ordering in Ternary Metallic Alloys D. D. Johnson* U.S. Department of Energy, DE-FG02-96ER45439 (In cooperation with the Frederick Seitz Materials Research Laboratory and Sandia National Laboratories) The degree to which ordering (chemical and magnetic) exists in high-temperature alloys can be probed by diffuse scattering experiments. Researchers develop and apply a first-principles theory of alloys to compare directly and explain experimental data based on the underlying electronic and magnetic interactions. For the first time, the results of the scattering experiments can be related directly to the electronic structure of metallic alloys, thereby elucidating the microscopic reasons for the structural ordering and providing valuable guidance in the design of new and improved alloys. This represents a significant advance in alloy theory. Dynamics of Phase Inversion Related to Drug Delivery A. J. McHugh,* J. R. DesNoyer, K. J. Brodbeck National Science Foundation, CTS 97-31509; Alza Corp. The principles of phase inversion are being applied in studies of injectable drug delivery systems consisting of a water-insoluble polymer, biocompatible solvent, and bioactive agent. In situ optical measurement techniques are used to quantify the interaction of liquid demixing, gelation, and drug release rates in solutions quenched into an aqueous environment. Water influx rates and bath-side mass transfer dynamics are correlated with the drug release rate and morphology of the formed gel. Systems under study include poly (lactide-co-glycolide) (PLGA) copolymers of various molecular weights and composition, a variety of biocompatible solvent systems, and model protein systems such as chicken egg lysozyme. Turbulence Simulation for Solid-Rocket Applications R. D. Moser,* R. J. Adrian, S. Balachandar, P. Venugopal, F. Najjar, Z. Deng U.S. Department of Energy, Center for Simulation of Advanced Rockets New large-eddy simulation (LES) model and simulation techniques are being developed for use in the simulation of solid-rocket motors. Solid-rocket flows present interesting challenges to turbulence simulation, including large transpiration, combustion, large-temperature and density variations, and burning particles. These complications will be treated using the optimum LES modeling technique based on stochastic estimation. Neural Control, Active Sensing, and Sensorimotor Integration in Hexapod Robots M. Nelson,* N. Ahuja* U.S. Office of Naval Research, N00014-96-1-0657 (Conducted in the Beckman Institute for Advanced Science and Technology) The overall goal of this research project is to design, construct, and evaluate integrated active sensing and motor control systems for legged robots using insights provided by insect neurobiology. Researchers are developing neurally inspired control systems for insect-like robots that incorporate mechanosensory signals from leg sensors and visual signals from an active vision system to carry out visually guided behavior in complex environments that may include obstacles and irregular terrain. The biological basis for this work is provided by a large body of anatomical, physiological, and behavioral studies of cockroaches, walking sticks, crickets, locusts, and mantids. Integrated Mesoscopic Cooler Circuits (IMCCs): A Transforming Technology of Robust Ultraefficient Environmental Control for Warriors of the 21st Century M. L. Philpott,* M. A. Shannon,* J. Economy, A. A. Rockett, C. W. Bullard, A. M. Jacobi, T. A. DeTemple, D. J. Beebe, K. C. Hsieh, N. R. Miller, H. Sehitoglu, P. S. Hrnjak, M. T. A. Saif, N. Aluru Defense Advanced Research Projects Agency A system of lightweight micro-coolers is being developed by combining new layered mesoscopic fabrication techniques with a scale-efficient vapor-compression cycle. A network of compliant electrically powered devices approximately 120 mm (4.7 in.) square and 3 mm (< 1/8 in.) thick are meshed together to form an active cooling fabric. The mesoscopic processes under development combine polyimide/thin-film layering technologies with silicon-based electromechanical device fabrication. An important potential application is the cooling of military personnel on active duty in hot climates. Other potential applications include cooling of microelectronics and infrared sensors and weapon systems that can benefit from robust distributed cooling. An Integrated Framework for Performance Engineering and Resource-Aware Compilation C. Polychronopoulos,* W. H. Sanders, T. Huang, S. Carroll, Y. Chen, G. Clark, T. Courtney, D. Daly, D. D. Deavours, S. Derisavi, P. Kalogiannis, W. Ko, F. Koopmans, J. Lin, K. Marukawa, N. Petrovic, Q. Tian, P. Webster, Y. Wu, M. Yankelevsky, X. Zhou National Science Foundation, EIA 99-75019 (In cooperation with the Coordinated Science Laboratory) Design of next-generation computing and communication systems will be application-driven and will require fundamental advances in performance engineering frameworks, methods, and tools and in adaptive compilation and run-time support techniques. This work takes a systematic and synergetic approach to developing both of these capabilities and will demonstrate their use via application to several important distributed applications. In conducting the work, researchers will make fundamental advances in techniques for system and model composition, multilevel/formalism modeling and performance evaluation, adaptive compilation, and dynamic run-time support. Context-Sensitive Natural Language Inferences D. Roth,* A. Carlson National Science Foundation, IIS-980163; IBM Corp. The future of intelligent human-machine interaction is in the ability to perform context-sensitive inferences. These are knowledge intensive tasks that are difficult to make without a significant learning component. This research studies a learning approach that targets language-understanding related tasks and directly addresses the issue of scalability. Context-sensitive inferences are required at different levels of sentence processing, from word-sense disambiguation (for example, the use of the word "plant" in different contexts), to phrase interpretation (such as "move the car with the flag"). This project concentrates on the problem of context-sensitive text correction—the task of fixing spelling errors that result in valid words, such as substituting "to" for "too," "out" for "our," "now" for "know," and so on. The system is trained directly from data (sentences read from on-line newspapers) and in its current form can represent (and correct mistakes for) about 1,000 words. The approach developed can be applied to support a variety of inferences of the sort required in intelligent human-machine interactions as demonstrated in this project by developing a system that exhibits a wide coverage and accurate context-sensitive spelling correction. A demonstration of the context-sensitive text correction system is available at http://L2R.cs.uiuc.edu/~cogcomp/. This work received the American Association of Artificial Intelligence (AAAI) 2001 Innovative Applications of AI Award. 3-D Influence Correction Scheme for Application to 2-D Design M. S. Selig,* M. D. Soso Ford Motor Co. Two-dimensional airfoils designed for racecar applications undergo significant performance changes when their low aspect ratio, 3-D counterparts are used in the real situation. To compensate for these changes, endplates are attached to both ends of the wings. Research is being carried out to develop a 3-D influence correction scheme that incorporates the effective aspect ratio of the endplates into the initial 2-D airfoil design. This should allow closer matching of the initial design characteristics with the final product. Characterization of Scales in the Chicago Water Distribution System V. L. Snoeyink,* P. Sarin, D. Frommell, W. Kriven City of Chicago, Ill. The objective of this project is to determine the chemical composition of scales that have been found on cement- and mortar-lined distribution pipes and to determine ways to control the formation of this scale. The approach involves use of energy dispersive spectroscopy to determine elemental composition and nuclear magnetic resonance spectroscopy to determine chemical structure. A pipe-loop system with lead pipe harvested from the Chicago system is being used to show the impact of any changes in aluminum concentration and phosphate dose on lead release. Development of Virtual Prototyping Systems R. S. Sreenivas,* W. R. Norris Caterpillar, Inc. The notion of "steering quality" is difficult to quantify in the design of steering systems for earth-moving vehicles. Researchers envision an expert driver operating a simulated vehicle within a virtual environment where the parameters in the design of a steering system can be altered instantaneously. In this paradigm, the process of trial-and-error design becomes a viable option. This project involves the derivation of vehicle models of appropriate complexity and detail that can be simulated in real-time within a virtual environment. To improve the real-time performance of these models, particular attention is focused on artificial neural networks. Characterizing Dual Magnetic Resonance Imaging and Boron Neutron Capture Therapy Reagents E. Wiener,* N. Pederson National Institutes of Health, PHS 2P41 RR 05964-06 Neutron capture therapy (NCT) is a binary technique that delivers a nonradioactive agent to the tumor followed by neutron irradiation and conversion of the agent into a radioactive compound. To predict the efficacy of the treatment, one must run dosimetric calculations. This implies an a priori knowledge of the drug concentration. One technique uses a method based on the tumor enhancement achieved with gadolinium labeled derivatives and magnetic resonance imaging (MRI). This requires an understanding of the magnetic properties of the agents under physiological conditions. The focus of this research is on characterizing a gadolinium-labeled carbon derivative for dual MRI and NCt applications.
Turbulence simulation of a solid rocket flow.