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Small-Angle X-Ray Studies Of Soot Inception And Growth, Jan P. Hessler, Soenke Seifert, Randall E. Winans, Thomas H. Fletcher Jan 2001

Small-Angle X-Ray Studies Of Soot Inception And Growth, Jan P. Hessler, Soenke Seifert, Randall E. Winans, Thomas H. Fletcher

Faculty Publications

The high spectral intensity of X-rays produced by the undulator at the Basic Energy Sciences Synchrotron Radiation Center of Argonne's Advanced Photon Source has allowed us to perform small-angle X-ray scattering (SAXS) studies of the initial distribution of soot particles formed by various fuels. SAXS provides an in situ probe of the morphology of soot in the region between 1 and 100 nm and complements the ex situ technique of electron microscopy. The basic aspects of SAXS and its potential are illustrated with measurement on a laminar flame of acetylene in air. The more complex fuel toluene has been studied …

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Holding-Up More Than Half The Sky: Marketization And The Status Of Women In China, Anna M. Han Jan 2001

Holding-Up More Than Half The Sky: Marketization And The Status Of Women In China, Anna M. Han

Faculty Publications

The purpose of this article is to examine generally how Chinese women fared under communism and more specifically, delve into how marketization has adversely impacted the status of women in China. It is this author's contention that despite the overall improvements in the standard of living, Chinese women are increasingly being marginalized economically. The long-term effects of subjugating the advancement of women for the immediate benefits of China's experimentation with a market economy hold vast implications for the future of the country. As China progresses economically, politically and socially, it cannot afford to leave half of its population behind as …

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Magmatic And Hydrothermal Activity In Lena Trough, Arctic Ocean, Jonathan Snow, Eric Hellebrand, Wilfried Jokat, Richard Muhe Jan 2001

Magmatic And Hydrothermal Activity In Lena Trough, Arctic Ocean, Jonathan Snow, Eric Hellebrand, Wilfried Jokat, Richard Muhe

Faculty Publications

No abstract provided.

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Hysteresis During Cycling Of Nickel Hydroxide Active Material, Venkat Srinivasan, John W. Weidner, John Newman Jan 2001

Hysteresis During Cycling Of Nickel Hydroxide Active Material, Venkat Srinivasan, John W. Weidner, John Newman

Faculty Publications

The nickel hydroxide electrode is known to exhibit a stable hysteresis loop, with the potential on charge being higher than that on discharge at every state-of-charge (SOC). What we show here is that this loop created during a complete charge and discharge (i.e., boundary curves) is not sufficient to define the state of the system. Rather, internal paths within the boundary curves (i.e., scanning curves) can be generated that access potentials between the boundary curves. The potential obtained at any SOC, as well as how the material charges and discharges from that point, depends on the …

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Approximate Solutions For Galvanostatic Discharge Of Spherical Particles I. Constant Diffusion Coefficient, Venkat R. Subramanian, James A. Ritter, Ralph E. White Jan 2001

Approximate Solutions For Galvanostatic Discharge Of Spherical Particles I. Constant Diffusion Coefficient, Venkat R. Subramanian, James A. Ritter, Ralph E. White

Faculty Publications

Approximate models are developed, based on second, fourth, and sixth order polynomials, that describe the concentration profile of an electrochemically active species in a spherical electrode particle. Analytical expressions are obtained that describe the way the concentration profiles, surface concentrations, and electrode utilization change during the galvanostatic discharge of an electrode particle. Based on a comparison with an exact analytical model over a wide range of dimensionless current densities, all three approximate models performed extremely well in predicting these quantities. Quantitative criterion for the validity of these models is also developed and shows that the sixth order, four parameter approximate …

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Modeling Of A Nickel-Hydrogen Cell: Phase Reactions In The Nickel Active Material, B. Wu, Ralph E. White Jan 2001

Modeling Of A Nickel-Hydrogen Cell: Phase Reactions In The Nickel Active Material, B. Wu, Ralph E. White

Faculty Publications

No abstract provided.

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Modeling Lithium Intercalation In A Porous Carbon Electrode, Gerardine G. Botte, Ralph E. White Jan 2001

Modeling Lithium Intercalation In A Porous Carbon Electrode, Gerardine G. Botte, Ralph E. White

Faculty Publications

No abstract provided.

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The Jeffersonian Vision Of Legal Education, Davison M. Douglas Jan 2001

The Jeffersonian Vision Of Legal Education, Davison M. Douglas

Faculty Publications

No abstract provided.

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Dynamics Of Stars And Globular Clusters In M87, Aaron J. Romanowsky, C. S. Kochanek Jan 2001

Dynamics Of Stars And Globular Clusters In M87, Aaron J. Romanowsky, C. S. Kochanek

Faculty Publications

We examine the dynamics of the stars and globular clusters in the nearby giant elliptical galaxy M87 and constrain the mass distribution, using all the available data over a large range of radii, including higher order moments of the stellar line-of-sight velocity distributions and the discrete velocities of over 200 globular clusters. We introduce an extension of spherical orbit modeling methods that makes full use of all the information in the data and provides very robust constraints on the mass models. We conclusively rule out a constant mass-to-light ratio model and infer that the radial density profile of the galaxy's …

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Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler Jan 2001

Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler

Faculty Publications

No abstract provided.

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A Non-Authoritative Educational Metadata Ontology For Filtering And Recommending Learning Objects, David Wiley, Mimi M. Recker Jan 2001

A Non-Authoritative Educational Metadata Ontology For Filtering And Recommending Learning Objects, David Wiley, Mimi M. Recker

Faculty Publications

Digital libraries populated with learning objects are becoming popular tools in the creation of instructional technologies. Many current efforts to create standard metadata structures that facilitate the discovery and instructional use of learning objects recommend a single, authoritative metadata record per version of the learning object. However, as we argue in this paper, a single metadata record -- particularly one with fields that emphasize knowledge management and technology, while evading instructional issues -- provides information insufficient to support instructional utilization decisions. To put learning objects to instructional use, users must examine the individual objects, forfeiting the supposed benefits of the …

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Nature Writing, American Literature, And The Idea Of Community: A Conversation With Barry Lopez, David Thomas Sumner Jan 2001

Nature Writing, American Literature, And The Idea Of Community: A Conversation With Barry Lopez, David Thomas Sumner

Faculty Publications

This interview with Barry Lopez is part of a series of conversations with contemporary western writers about the ethical and cultural implications of nature writing.

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Non-Social Play As A Risk Factor In Social And Emotional Development, Charissa S. L. Cheah, Larry J. Nelson, Kenneth H. Rubin Jan 2001

Non-Social Play As A Risk Factor In Social And Emotional Development, Charissa S. L. Cheah, Larry J. Nelson, Kenneth H. Rubin

Faculty Publications

Children spend much of their youthful energy engaged in play. Indeed, play, in its various forms, represents a serious business – not only for the active participations, but also for students of the phenomenon. To many researchers, play is viewed as a generative fore in children's social, emotional, and cognitive development (see Rubin, Fein, & Vandenberg, 1983; Saracho & Spodek, 1998; Fromberg & Bergen, 1998). The extent to which children engage in play with others is of added developmental significance. In light of the complexity and developmental significance of children's play and especially play with peers, it seems important to …

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On Parsing The Within-Stand Variability In Stand Density Measures, Mark J. Ducey, Bruce C. Larson Jan 2001

On Parsing The Within-Stand Variability In Stand Density Measures, Mark J. Ducey, Bruce C. Larson

Faculty Publications

A variety of stand-density measures have become popular in North America for diagnosing thinning needs, predicting thinning outcomes, and to an increasing degree, regulating legal harvesting behavior. The statistical reliability of these measures is seldom included in the analysis, but the confidence limits of the measures must be considered if they are used in these ways.  These indices are designed to measure average stocking, but conventional approaches do not address issues of stand heterogeneity.  If the variability of the sample estimates is calculated in order to determine statistical reliability, it is then tempting to use that variability to address two …

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Probability And Agents, Marco Valtorta, Michael N. Huhns Jan 2001

Probability And Agents, Marco Valtorta, Michael N. Huhns

Faculty Publications

To make sense of the information that agents gather from the Web, they need to reason about it. If the information is precise and correct, they can use engines such as theorem provers to reason logically and derive correct conclusions. Unfortunately, the information is often imprecise and uncertain, which means they will need a probabilistic approach. More than 150 years ago, George Boole presented the logic that bears his name. There is concern that classical logic is not sufficient to model how people do or should reason. Adopting a probabilistic approach in constructing software agents and multiagent systems simplifies some …

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Measurement Of The Neutral Current Cross Section And F2 Structure Function For Deep Inelastic E+P Scattering At Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci Jan 2001

Measurement Of The Neutral Current Cross Section And F2 Structure Function For Deep Inelastic E+P Scattering At Hera, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari, A. Pesci

Faculty Publications

The cross section and the proton structure function F2 for neutral current deep inelastic e+p scattering have been measured with the ZEUS detector at HERA using an integrated luminosity of 30 pb-1. The data were collected in 1996 and 1997 at a centre-of-mass energy of 300 GeV. They cover the kinematic range 2.7 < Q2 < 30000 GeV2 and 6-10-5 < cursive Greek chi < 0.65. The variation of F2 with cursive Greek chi and Q2 is well described by next-to-leading-order perturbative QCD as implemented in the DGLAP evolution equations.

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Measurement Of Open Beauty Production In Photoproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Jan 2001

Measurement Of Open Beauty Production In Photoproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

The production and semi-leptonic decay of heavy quarks have been studied in the photoproduction process e+p → e+ + dijet + e- + X with the ZEUS detector at HERA using an integrated luminosity of 38.5 pb-1. Events with photon-proton centre-of-mass energies, Wγp, between 134 and 269 GeV and a photon virtuality, Q2, less than 1 GeV2 were selected requiring at least two jets of transverse energy Ejet1(2)T > 7(6) GeV and an electron in the final state. The electrons were identified by employing the ionisation energy loss measurement. The contribution of beauty quarks was determined using the transverse momentum of …

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Search For Resonance Decays To A V̄ Plus Jet In E+P Scattering At Desy Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Lacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari Jan 2001

Search For Resonance Decays To A V̄ Plus Jet In E+P Scattering At Desy Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Lacobucci, G. Levi, A. Margotti, T. Massam, R. Nania, F. Palmonari

Faculty Publications

A study of the v̄-jet mass spectrum in e+p→v̄X events at a center-of-mass energy 300 GeV has been performed with the ZEUS detector at the HERA collider at DESY using an integrated luminosity of 47.7 pb-1. The mass spectrum is in good agreement with that expected from standard model processes over the v̄-jet mass range studied. No significant excess attributable to the decay of a narrow resonance is observed. By using both e+p→>e+X and e+p-vX data, mass-dependent limits are set on the s-channel production of scalar and vector resonant states. Couplings to first-generation quarks are considered and limits are …

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Gravitational Descendants And The Moduli Space Of Higher Spin Curves, Tyler J. Jarvis, Takashi Kimura, Arkady Vaintrob Jan 2001

Gravitational Descendants And The Moduli Space Of Higher Spin Curves, Tyler J. Jarvis, Takashi Kimura, Arkady Vaintrob

Faculty Publications

The purpose of this note is introduce a new axiom (called the Descent Axiom) in the theory of r-spin cohomological field theories. This axiom explains the origin of gravitational descendants in this theory. Furthermore, the Descent Axiom immediately implies the Vanishing Axiom, explicating the latter (which has no a priori analog in the theory of Gromov-Witten invariants), in terms of the multiplicativity of the virtual class. We prove that the Descent Axiom holds in the convex case, and consequently in genus zero.

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Microstructure-Sensitive Design Of A Compliant Beam, Brent L. Adams, Alisa J. Millar Henrie, B. Henrie, M. Lyon, H. Garmestani, Surya R. Kalidindi Jan 2001

Microstructure-Sensitive Design Of A Compliant Beam, Brent L. Adams, Alisa J. Millar Henrie, B. Henrie, M. Lyon, H. Garmestani, Surya R. Kalidindi

Faculty Publications

BA acknowledges financial support provided by the MRSEC Program of the National Science Foundation under Award Number DMR-9632556. SK acknowledges financial support from National Science Foundation under Award Number CMS-9732699. BA, SK and HG also acknowledge support from the NSF-CIRE program centered at Florida A&M University, facilitating collaborations. Support was also provided by the College of Engineering and Technology at BYU (AH, BH and ML). Computations were performed on the new SGI Origin 2000 supercomputer at Brigham Young University, donated by Ira Fulton. We show that mechanical design can be conducted where consideration of polycrystalline microstructure as a continuous design …

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Making Classical And Quantum Canonical General Relativity Computable Through A Power Series Expansion In The Inverse Cosmological Constant, Rodolfo Gambini, Jorge Pullin Dec 2000

Making Classical And Quantum Canonical General Relativity Computable Through A Power Series Expansion In The Inverse Cosmological Constant, Rodolfo Gambini, Jorge Pullin

Faculty Publications

Casting ordinary general relativity as a perturbative theory in Λ-1 and starting with background theory in which Λ → ∞ allows one to explicitly compute nondegenerate physical quantum states and observables. The technique is applicable in the theory in general and also in mini-super-space models. In the general theory, the calculations are well defined and tractable, but quite involved. This opens up a program for the quantization of the gravitational field that is well defined computationally and allows contact with the physical observables of the theory, a key ingredient in the road to finding a theory with a semiclassical regime …

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Land Use Impacts On Atmospheric Carbon Monoxide Consumption By Soils, G. M. King Dec 2000

Land Use Impacts On Atmospheric Carbon Monoxide Consumption By Soils, G. M. King

Faculty Publications

Seasonal analyses of in situ CO fluxes from forested and agricultural soils in Maine and Georgia, and more limited comparisons in Hawai'i indicated that agricultural land use consistently enhanced CO consumption. Soils at an agricultural site in Maine consumed approximately 1.9 g CO m-2 yr-1 while uptake in a nearby mixed forest was about 70% lower, 0.6 g CO m-2 yr-1. A similar trend was observed for sites in Georgia, where annual uptake by agricultural sites was approximately 1.0 g CO m-2 while net emission (about -0.5 g CO m-2) was observed for neighboring pine stands. Net CO fluxes in …

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A Simple Surface Temperature Assimilation Scheme For Use In Land Surface Models, Venkataraman Lakshmi Dec 2000

A Simple Surface Temperature Assimilation Scheme For Use In Land Surface Models, Venkataraman Lakshmi

Faculty Publications

This paper examines the utilization of surface temperature as a variable which can be assimilated in off-line land surface hydrological models. The connection between the surface temperature and evapotranspiration is utilized in making adjustments to the model-computed surface soil moisture. This adjustment is a function of the difference between the model-computed and the observed surface temperature. Comparisons between the model-computed and satellite-observed surface temperatures have been carried out. The assimilation of surface temperature is carried out twice a day (corresponding to the A.M. and P.M. overpass of the NOAA 10) over the Red-Arkansas basin in the southwestern United States (31°50′N-36°N, …

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Simplified Calculation Of The Stability Matrix For Semiclassical Propagation, Sophya Garashchuk, John C. Light Dec 2000

Simplified Calculation Of The Stability Matrix For Semiclassical Propagation, Sophya Garashchuk, John C. Light

Faculty Publications

We present a simple method of calculation of the stability (monodromy) matrix that enters the widely used semiclassical propagator of Herman and Kluk and almost all other semiclassical propagators. The method is based on the unitarity of classical propagation and does not involve any approximations. The number of auxiliary differential equations per trajectory scales linearly rather than quadratically with the system size. Just the first derivatives of the potential surface are needed. The method is illustrated on the collinear H[sub 3] system.

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The Environmental Science Minor: A Disciplinary Approach To Interdisciplinary Studies With A Grounding In Undergraduate Research, Brian E. Bodenbender, Edward C. Hansen, Graham F. Peaslee, Jonathan W. Peterson Dec 2000

The Environmental Science Minor: A Disciplinary Approach To Interdisciplinary Studies With A Grounding In Undergraduate Research, Brian E. Bodenbender, Edward C. Hansen, Graham F. Peaslee, Jonathan W. Peterson

Faculty Publications

No abstract provided.

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The Averaging Lemma, Ronald A. Devore, Guergana Petrova Nov 2000

The Averaging Lemma, Ronald A. Devore, Guergana Petrova

Faculty Publications

No abstract provided.

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Parallel Phylogenetic Inference, Mark J. Clement, David Mclaughlin, Quinn O. Snell, Michael Whiting Nov 2000

Parallel Phylogenetic Inference, Mark J. Clement, David Mclaughlin, Quinn O. Snell, Michael Whiting

Faculty Publications

Recent advances in DNA sequencing technology have created large data sets upon which phylogenetic inference can be performed. However, current research is limited by the prohibitive time necessary to perform tree search on even a reasonably sized data set. Some parallel algorithms have been developed but the biological research community does not use them because they don’t trust the results from newly developed parallel software. This paper presents a new phylogenetic algorithm that allows existing, trusted phylogenetic software packages to be executed in parallel using the DOGMA parallel processing system. The results presented here indicate that data sets that currently …

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The Large Cosmological Constant Approximation To Classical And Quantum Gravity: Model Examples, Rodolfo Gambini, Jorge Pullin Nov 2000

The Large Cosmological Constant Approximation To Classical And Quantum Gravity: Model Examples, Rodolfo Gambini, Jorge Pullin

Faculty Publications

We have recently introduced an approach for studying perturbatively classical and quantum canonical general relativity. The perturbative technique appears to preserve many of the attractive features of the non-perturbative quantization approach based on Ashtekar's new variables and spin networks. With this approach one can find perturbatively classical observables (quantities that have vanishing Poisson brackets with the constraints) and quantum states (states that are annihilated by the quantum constraints). The relative ease with which the technique appears to deal with these traditionally hard problems opens up several questions concerning how relevant the results produced can possibly be. Among the questions is …

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Toward Automated Abstraction For Protocols On Branching Networks, Michael D. Jones, Ganesh Gopalakrishnan Nov 2000

Toward Automated Abstraction For Protocols On Branching Networks, Michael D. Jones, Ganesh Gopalakrishnan

Faculty Publications

We have used various manual abstraction techniques to formally verify a transaction ordering property for an IO protocol over bus/bridge networks. In the context of network protocol verification, an abstraction is needed to reduce the unbounded number of network configurations to a small number of representative networks that can be checked using algorithmic methods. The manually derived abstraction was both brittle and difficult to validate. In this report, we discuss the need for abstraction techniques in the formal verification of protocols over networks and present our recent efforts to create an automatic abstraction technique for network protocols using predicate abstraction …

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System Level Microwave Design: Radar-Based Laboratory Projects, Michael A. Jensen, David V. Arnold, Donald E. Crockett Nov 2000

System Level Microwave Design: Radar-Based Laboratory Projects, Michael A. Jensen, David V. Arnold, Donald E. Crockett

Faculty Publications

Two laboratory projects-a Doppler radar and a synthetic aperture radar (SAR)-designed to augment traditional electromagnetics education are proposed. The projects introduce students to component and system level design and expose them to modern computer-aided design (CAD) tools, microstrip and surface mount fabrication technologies, and industry standard test equipment and procedures. Additionally, because the projects result in a working radar system, students gain new enthusiasm for the electromagnetics discipline and directly see its relevance in the engineering field. Implementation of these laboratories within the curriculum have proven to be highly motivational and educational and have even contributed to increased enrolments in …

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