Digital Commons Network^™

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 …

Multimode Quantitative Scanning Microwave Microscopy Of In Situ Grown Epitaxial Ba1-XSrXTio3 Composition Spreads, K. S. Chang, M. Aronova, O. Famodu, I. Takeuchi, S. E. Lofland, Jason R. Hattrick-Simpers, H. Chang

Faculty Publications

We have performed variable-temperature multimode quantitative microwavemicroscopy of in situepitaxial Ba_1−xSr_xTiO₃ thin-film composition spreads fabricated on (100) LaA₁O₃ substrates. Dielectric properties were mapped as a function of continuously varying composition from BaTiO₃ to SrTiO₃. We have demonstrated nondestructive temperature-dependent dielectric characterization of local thin-film regions. Measurements are simultaneously taken at multiple resonant frequencies of the microscope cavity. The multimode measurements allow frequency dispersion studies. We observe strong composition-dependent dielectric relaxation in Ba_1−xSr_xTiO₃ at microwave frequencies.

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 …

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

Faculty Publications

No abstract provided.

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

Faculty Publications

No abstract provided.

Synthesis And Characterization Of Hydrous Ruthenium Oxide-Carbon Supercapacitors, Manikandan Ramani, Bala S. Haran, Ralph E. White, Branko N. Popov

Faculty Publications

It is shown that composite Ru oxide-carbon based supercapacitors possess superior energy and power densities as compared to bare carbon. An electroless deposition process was used to synthesize the ruthenium oxide-carbon composites. Ru is dispersed on the carbon matrix as small particles. The effect of electrochemical oxidation and temperature treatment on the material performance has been studied extensively. Increasing the oxidation temperature reduces the proton transport rate and also increases the degree of crystallinity of the deposits. This adversely affects the performance of the composite. Loading a small amount of Ru oxide (9 wt %) on carbon increases the capacitance …

Observable Behavior For Implicit User Modeling: A Framework And User Studies, Jinmook Kim, Douglas W. Oard

Faculty Publications

This paper presents a framework for observable behavior that can be used as a basis for user modeling, and it reports the results of a pair of user studies that examine the joint utility of two specific behaviors. User models can be constructed by hand, or they can be learned automatically based on feedback provided by the user about the relevance of documents that they have examined. By observing user behavior, it is possible to obtain implicit feedback without requiring explicit relevance judgments. Four broad categories of potentially observable behavior are identified: examine, retain, reference, and annotate, and examples of …

Modeling Information Content Using Observable Behavior, Douglas W. Oard, Jinmook Kim

Faculty Publications

This paper presents a framework for modeling the content of information objects such as documents and video programs based on observation of how users interact with those objects in the course of information seeking and use. Four categories of potentially observable user behaviors are identified: examination, retention, reference, and annotation. The framework draws together techniques from the information filtering, Web searching and citation indexing, and identifies the natural scope (portion of an object, complete object, or collection of objects) at which each behavior can be observed. The process of using observations as a basis for identifying information that may be …

User Modeling For Information Filtering Based On Implicit Feedback, Jinmook Kim, Douglas W. Oard, Kathleen Romanik

Faculty Publications

No abstract provided.

Center, Margin, And Myth In Fergus Lamont And Lanark, Cristie L. March

Studies in Scottish Literature

No abstract provided.

The Dillow’S Ridge Site And The Production Of Mill Creek Chert Tools, Brian M. Butler, Charles R. Cobb

Faculty Publications

The Dillow's Ridge site (11 U635) is a small Mississippian village situated on an unplowed hilltop near the largest known Mill Creek chert quarry in Union County, Illinois. The site was both a permanent residential settlement and a major workshop where Mill Creek chert tools were produced for nonlocal use. Radiocarbon dates document the occupation from the late 1200s A.D. to A.D. 1450 or 1500. The production debris and rejects indicate that the major “export" products were hoes and Ramey knives. Although the quantity of lithic debris on the site is very impressive, estimates of annual production of large biface …

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 …

December 6, 2000 Faculty Senate Minutes, University Of South Carolina

Faculty Senate

No abstract provided.

High-Quality P-N Junctions With Quaternary Alingan/Ingan Quantum Wells, A. Chitnis, A. Kumar, M. Shatalov, V. Adivarahan, A. Lunev, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur

Faculty Publications

We report on quaternary AlInGaN/InGaN multiple quantum well(MQW)light emitting diode structures grown on sapphire substrates. The structures demonstrate high quality of the p–njunctions with quaternary MQW. At low forward bias (below 2 V), the temperature dependent of current–voltage characteristics are exponential with the ideality factor of 2.28, which is in a good agreement with the model of the injected carrier recombination in the space charge region. This ideality factor value is approximately three times lower than for conventional GaN/InGaN light emitting diodes(LEDs). The obtained data indicate the recombination in p–njunction space charge region to be responsible for a current transport …

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.

Legacy - December 2000, South Carolina Institute Of Archaeology And Anthropology--University Of South Carolina

SCIAA Magazine - Legacy & PastWatch

Contents:

H.L. Hunley Completes the Journey Home.....p. 1
Director’s Notes.....p. 2
Mepkin Wreck Project.....p. 10
Willtown Report.....p. 13
Le Prince Research.....p. 14
Great Pee Dee River Survey.....p. 16
Overcollecting in SC Waters.....p. 17
Delinquent Hobby Diver Reporting.....p. 17
Field Training Course Offered.....p. 17
Allendale 2000 Field Season.....p. 18
African-American Cemetery.....p. 26
Santa Elena Designated as National Landmark.....p. 28
Sandy Island Research.....p. 29
New Book on the Swamp Fox.....p. 31
Digital Mills' Atlas Project.....p. 32
SCIAA Researchers Funded.....p. 34
ART Donors in 2000.....p. 35
ART Board Activities.....p. 36
SC Archaeology Month 2000.....p. 37
George Bass to Speak at Annual ASSC …

Functional Projections Of Predicates: Experimental Evidence From Coordinate Structure Processing, Stanley William Dubinsky, Marie Egan, A. Rene Schumauder, Matthew J. Traxler

Faculty Publications

This paper reports the results of six experiments involving an on-line self-paced reading task that examine the processing of coordinate small clause predicate phrases versus coordinated arguments NPs. The results have particular significance for the analysis of small clause complement constructions, and support accounts wherein the small clause complement has an Agr projection associated with it. An adequate explanation of the processing of small clause coordination is shown to motivate a new parsing principle, Coordination Feature-matching, which accounts for the longer reading times observed for the coordination of predicates in small clause complements.

Storming Normandy: A Recovery Mission To The French Archives Of Rouen And Caen, James D. Spirek

Faculty & Staff Publications

No abstract provided.

The Confessions Of Edward Isham: A Poor White Life Of The Old South, By Edward Isham, Edited By Charles C. Bolton And Scott P. Culclasure, Lacy K. Ford, Jr.

Faculty Publications

A review of The Confessions of Edward Isham: A Poor White Life of the Old South, by Edward Isham, edited by Charles C. Bolton and Scott P. Culclasure

Effect Of Gate Leakage Current On Noise Properties Of Algan/Gan Field Effect Transistors, S. L. Rumyantsev, N. Pala, M. S. Shur, R. Gaska, M. E. Levinshtein, M. Asif Khan, Grigory Simin, X. Hu, J. Yang

Faculty Publications

The effect of the gate leakage current fluctuations on noiseproperties of AlGaN/GaN heterostructurefield effect transistors(HFETs) has been studied in conventional HFET structures and in AlGaN/GaN metal-oxide-semiconductorheterostructurefield effect transistors (MOS-HFETs). The comparison of the noiseproperties of conventional AlGaN/GaN HFETs and AlGaN/GaN MOS-HFETs fabricated on the same wafer, allowed us to estimate the contribution of the gate currentnoise to the HFET’s output noise. The effect of the gate current fluctuations on output noiseproperties of HFETs depends on the level of noise in the AlGaN/GaN HFETs. For the transistors with a relatively high magnitude of the Hooge parameter α∼10⁻³, even a …

Proteolytic Enzymes In The Marine Bacterium Pseudoalteromonas Atlantica: Post-Secretional Activation And Effects Of Environmental Conditions, Monica Hoffman, Alan W. Decho

Faculty Publications

Production and activities of cellular and extracellular proteolytic enzymes associated with the marine bacterium Pseudoalteromonas atlantica were examined in response to physiological state and changing environmental variables under laboratory conditions. Enzymes evidenced by zymography were metalloproteases, as defined by substrate preference and susceptibility to inhibitors (EDTA and 1, 10-phenanthroline). Distinct bands (i.e. molecular-weight [MW] size classes) of enzymes were isolated from within cellular and extracellular compartments. Susceptibility of extracellular enzymes to environmental stressors was related, in part, to the MW size classes of the enzymes. While all bands of enzymes showed some degree of inhibition when pH was decreased, the …

The Averaging Lemma, Ronald A. Devore, Guergana Petrova

Faculty Publications

No abstract provided.

The Use Of Uniaxial And Triaxial Accelerometers To Measure Children's "Free-Play" Physical Activity, Alise E. Ott, Russell R. Pate, Stewart G. Trost, Dianne S. Ward, Ruth P. Saunders

Faculty Publications

In order to effectively measure the physical activity of children, objective monitoring devices must be able to quantify the intermittent and nonlinear movement of free play. The purpose of this study was to investigate the validity of the Computer Science and Applications (CSA) uniaxial accelerometer and the TriTrac-R3D triaxial accelerometer with respect to their ability to measure 8 "free-play" activities of different intensity. The activities ranged from light to very vigorous in intensity and included activities such as throwing and catching, hopscotch, and basketball. Twenty-eight children, ages 9 to 11, wore a CSA and a heart rate monitor while performing …

November 1, 2000 Faculty Senate Minutes, University Of South Carolina

Faculty Senate

No abstract provided.

Flotsam And Jetsam - November 2000, South Carolina Institute Of Archaeology And Anthropology--University Of South Carolina

Sport Diver Newsletters

Contents:

Dive Club Concerned About Overcollection..... p.2
Reminder Notices Sent To Delinquent Hobby Divers..... p.2
Diver Completes Report On Willtown..... p.3
Hunley Raised!..... p.4
Mepkin Wreck Project Continues..... p.6
What I Did This Summer..... p.8
Archival Quest For Le Prince Continues..... p.10
Remote Sensing Survey of Great Pee Dee River To Inventory Underwater Archaeological Sites..... p.11

Dna Binding Properties Of The Arabidopsis Floral Development Protein Aintegumenta, Staci Nole-Wilson, Beth A. Krizek

Faculty Publications

The Arabidopsis protein AINTEGUMENTA (ANT) is a member of a plant-specific family of transcription factors (AP2/EREBP) that share either one or two copies of an approximately 70 amino acid region called the AP2 repeat. DNA binding activity has been demonstrated previously for members of this family containing a single AP2 repeat. Using an in vitro selection procedure, the DNA binding specificity of the two AP2 repeat containing protein ANT was found to be 5'-gCAC(A/G)N(A/T)TcCC(a/g)ANG(c/t)-3'. This consensus site is much longer than sites recognized by proteins containing a single AP2 repeat and neither AP2 repeat of ANT was alone capable of …

Emotion And Group Cohesion In Productive Exchange, Edward J. Lawler, Shane R. Thye, Jeongkoo Yoon

Faculty Publications

This study refines and experimentally tests a theory of relational cohesion that explains how and when actors become committed to one another in the context of multiactor exchange. The theory asserts that frequent social exchange results in (1) positive emotions that solidify and strengthen the person-to-group bond and (2) uncertainty reduction that renders the focal group more salient in relation to others. These two mechanisms produce a sense of psychological group formation and ultimately increase observable acts of commitment. In a “productive exchange” setting, three actors negotiate a joint venture that requires the assent of all members. The exchanges featured …

Archival Quest For Le Prince Continues, James D. Spirek

Faculty & Staff Publications

No abstract provided.

Hop Integrity In Computer Networks, Mohamed G. Gouda, E.N. Elnozahy, Chin-Tser Huang, Tommy M. Mcguire

Faculty Publications

A computer network is said to provide hop integrity iff when any router p in the network receives a message m supposedly from an adjacent router q, then p can check that m was indeed sent by q, was not modified after it was sent, and was not a replay of an old message sent from q to p. We describe three protocols that can be added to the routers in a computer network so that the network can provide hop integrity. These three protocols are a secret exchange protocol, a weak integrity protocol, and a strong integrity protocol. All …

High Performance Micropane Electron Beam Window, Roger A. Dougal, Shengyi Liu

Faculty Publications

A silicon disk etched so that it contains a multitude of microscopic and thin window panes (micropanes) can potentially transmit a larger average electron beam current density and absorb a smaller fraction of the beam energy than a common metal foil window. The enhanced performance is achieved by a combination of decreased power loss due to the extremely small window thickness (~1 μm), and increased conductive cooling due to the small diameter (~50 μm) of the micropanes and the large cross section of the honeycomb structure that supports the micropanes. Beam current densities up to 34 A/cm2 are permitted within …