Physical Sciences and Mathematics Commons^™

Automatic Estimation Of The Seafloor Geomorphology Of The Santos Basin, Brazil, Brian R. Calder, Luciano E. Fonseca, Joao B. Francolin

Center for Coastal and Ocean Mapping

The bathymetry and acoustic backscatter of Santos Basin, Brazil were mapped using a SeaBeam 2112 (12 kHz, 151 beam) Multibeam Echosounder (MBES) aboard the R/V Falcon Explorer. This MBES data was acquired from January-November, 2000, during a high-resolution multi-channel 3D seismic survey, resulting in 380 parallel lines of 90 km length, spaced 250 m apart. The final survey mapped an area of 5,000 km${}^2$ in water depths of 900--2000 m. These closely spaced multibeam tracks resulted in an average overlap between swaths of 1000%, thereby ensonifying most areas of the seafloor at least ten times. Traditional (hand) processing of a …

Computer Sciences At Purdue University 1962 To 2000, John R. Rice, Saul Rosen

Department of Computer Science Technical Reports

No abstract provided.

Periodicity Detection In Time Series Databases, Mohamed G. Elfeky, Walid G. Aref, Mikhail J. Atallah

Department of Computer Science Technical Reports

No abstract provided.

Multi-Dimenstional Traversals For Normalization Constants, Jorge R. Ramos, Vernon J. Rego

Department of Computer Science Technical Reports

No abstract provided.

Performance Of Multi-Dimensional Space- Filling Curves, Mohamed F. Mokbel, Walid G. Aref, Ibrahim Kamel

Department of Computer Science Technical Reports

No abstract provided.

Si Doping Of High-Al-Mole Fraction Alxga1-Xn Alloys With Rf Plasma-Induced Molecular-Beam-Epitaxy, Jeonghyun Hwang, William J. Schaff, Lester F. Eastman, Shawn T. Bradley, Leonard J. Brillson, David C. Look, J. Wu, Wladek Walukiewicz, Madalina Furis, Alexander N. Cartwright

Physics Faculty Publications

Very high levels of n-type doping of Al_xGa_1−xN alloys were recently achieved by rf plasma-induced molecular-beam epitaxy on sapphire substrates and Si as a dopant. Electron concentrations were obtained up to 1.25×10²⁰ cm⁻³ when the Al mole fraction was 50%, and 8.5×10¹⁹ cm⁻³ electrons were measured even when the Al mole fraction was 80%. Other material properties were determined by optical absorption, photoluminescence, cathodoluminescence, x-ray diffraction, and atomic force microscopy measurements and high optical and morphological qualities were shown.

Recombination Of Excitons Bound To Oxygen And Silicon Donors In Freestanding Gan, A. Wysmolek, K. P. Korona, R. Stepniewski, J. M. Baranowsky, J. Bloniarz, M. Potemski, R. L. Jones, David C. Look, J. Kuhl, S. S. Park, S. K. Lee

Physics Faculty Publications

The neutral donor bound exciton recombination processes in freestanding GaN have been studied. The photoluminescence spectrum shows emission lines related to silicon and oxygen donors. Time-resolved luminescence allows us to correlate the principal donor bound exciton lines with their two-electron satellites. The magnetic field splitting of the two-electron lines is well described by the theory of the hydrogen atom in a magnetic field. For the oxygen donor a 1.5 meV chemical shift and a 30.8 meV effective Rydberg have been evaluated. Two-electron satellites involving excitations to the 2p and 2s donor states are separated by an energy of 1.0 and …

Normal Forms For Two-Inputs Nonlinear Control Systems, Issa Amadou Tall, Witold Respondek

Miscellaneous (presentations, translations, interviews, etc)

We study the feedback group action on two-inputs non-linear control systems. We follow an approach proposed by Kang and Krener which consists of analyzing the system and the feedback group step by step. We construct a normal form which generalizes that obtained in the single-input case. We also give homogeneous m-invariants of the action of the group of homogeneous transformations on the homogeneous systems of the same degree. We illustrate our results by analyzing the normal form and invariants of homogeneous systems of degree two.

An Observational Test Of The Spherical Model Atmospheres For The M Class Giants: The Case Of Δ2 Lyrae, Jeffrey J. Sudol, J. A. Benson, H. M. Dyck, M. Scholz

Physics & Engineering Faculty Publications

No abstract provided.

An Efficient Burst-Arrival And Batch- Departure Algoriths For Round-Robin Service, Jorge R. Ramos, Janche Sang

Department of Computer Science Technical Reports

No abstract provided.

Review Of "The Future Of Life," By Edward O. Wilson, Bryan Erickson

The University of New Hampshire Law Review

[Excerpt] "It is refreshing to read an environmental diatribe where the writer has both the authority of a world expert and a willingness to compromise to pursue realistic solutions. Wilson is a Harvard biology professor, two-time Pulitzer Prize winner, and a director of the Nature Conservancy. In The Future of Life, he presents a succinct evaluation of the great ecological issues of our day, focusing on the rapid pace of species extinctions, and on the promise of finding a balance between conservation and human activity that will bring the extinctions to a halt."

Electronic-Structure Modifications Induced By Surface Segregation In La0.65Pb0.35Mno3 Thin Films, C.N. Borca, B. Xu, T. Komesu, H.-K. Jeong, M.T. Liu, Sy_Hwang Liou, Shane Stadler, Y. Idzerda, Peter A. Dowben

Peter Dowben Publications

Using spin-polarized inverse photoemission and X-ray absorption spectroscopy techniques, we show that the electronic structure of La_0.65Pb_0.35MnO₃ thin films depends on the composition at the surface. With a gentle annealing procedure, the surface provides a maximum of 80% spin asymmetry at 0.5 eV above the Fermi level in spite of extensive Pb segregation. A heavily annealed (restructured) surface exhibits a reduced surface "ordering" temperature of 240 K (compared to the approximately 335 K bulk value) as well as a reduced spin asymmetry value of 40% at 0.5 eV above Fermi energy.

The Prairie Naturalist Volume 34, No. 3/4 September/December 2002

The Prairie Naturalist

SEASONAL FOOD HABITS OF COYOTES IN NORTHEASTERN KANSAS ▪ J. F. Kamler, P. S. Gipson, and C. C. Perchellet

SELECTION OF NESTING HABITAT BY SHARP-TAILED GROUSE IN THE NEBRASKA SANDHILLS ▪ B. L. Prose, B. S. Cade, and D. Hein

PATTERNS OF REPRODUCTION FOR WESTERN HARVEST MICE IN NORTH-CENTRAL KANSAS ▪ J. R. Goheen, G. A. Kaufman, and D. W. Kaufman

THE IMPACT OF RECREATIONAL TRAILS AND GRAZING ON SMALL MAMMALS IN THE COLORADO PIEDMONT ▪ C. A. Meaney, A. K. Ruggles, N. W. Clippinger, and B. C. Lubow

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA 2001 ▪ R. N. Randall …

Review Of "The Health Of Nations: Infectious Disease, Environmental Change, And Their Effects On National Security And Development," By Andrew T. Price-Smith, Andrew Mierins

The University of New Hampshire Law Review

[Excerpt] "Andrew T. Price-Smith, author of The Health of Nations: Infectious Disease, Environmental Change, and Their Effects on National Security and Development, provides a well documented and reasoned analysis of the need for world leaders, including the United States, to place the threat of infectious disease on the front burner of consideration when shaping both national and international policy. Professor Price-Smith has provided both empirical data and historical analysis to support the impassioned plea for this natural threat to be taken seriously. The book is geared toward the academic community and policy analysts; however, other professionals not involved in these …

The Role Of Climate In Modern Water Planning And Related Decisions: Nebraska Case Study, Donna L. Woudenberg

Open Access Master's Theses (through 2010)

Climate and weather play an integral role in the planning and decision-making processes for those involved in agricultural and natural resource fields. This project was conducted to determine whether climate and weather data are being efficiently and effectively used in these processes.

A survey was mailed to those who work in water-related fields in Nebraska and post-survey interviews were conducted to obtain greater detail. Survey results were analyzed in the following three ways: as a whole; stratified by respondent’s agency; and stratified by the educational background of respondents. It was found that climate and weather data are more likely to …

On Choosing And Bounding Probability Metrics, Alison L. Gibbs, Francis E. Su

All HMC Faculty Publications and Research

When studying convergence of measures, an important issue is the choice of probability metric. We provide a summary and some new results concerning bounds among some important probability metrics/distances that are used by statisticians and probabilists. Knowledge of other metrics can provide a means of deriving bounds for another one in an applied problem. Considering other metrics can also provide alternate insights. We also give examples that show that rates of convergence can strongly depend on the metric chosen. Careful consideration is necessary when choosing a metric.

On Computing Condensed Frequent Pattern Bases, Jian Pei, Guozhu Dong, Wei Zou, Jiawei Han

Kno.e.sis Publications

Frequent pattern mining has been studied extensively. However, the effectiveness and efficiency of this mining is often limited, since the number of frequent patterns generated is often too large. In many applications it is sufficient to generate and examine only frequent patterns with support frequency in close-enough approximation instead of in full precision. Such a compact but close-enough frequent pattern base is called a condensed frequent patterns-base.

In this paper, we propose and examine several alternatives at the design, representation, and implementation of such condensed frequent pattern-bases. A few algorithms for computing such pattern-bases are proposed. Their effectiveness at pattern …

Web Service Technologies And Their Synergy With Simulation, Senthilanand Chandrasekaran, Gregory S. Silver, John A. Miller, Jorge Cardoso, Amit P. Sheth

Kno.e.sis Publications

The World Wide Web has had a huge influence on the computing field in general as well as simulation in particular (e.g., Web-Based Simulation). A new wave of development based upon XML has started. Two of the most interesting aspects of this development are the Semantic Web and Web Services. This paper examines the synergy between Web service technology and simulation. In one direction, Web service processes can be simulated for the purpose of correcting/improving the design. In the other direction, simulation models/components can be built out of Web services. Work on seamlessly using simulation as a part of Web …

Historical Development Of The Linear Nonthreshold Dose-Response Model As Applied To Radiation, Ronald L. Kathren

The University of New Hampshire Law Review

[Excerpt] "Despite the nearly universal adoption of the linear nonthreshold dose response model (LNT) as the primary basis for radiation protection standards for the past half century, the LNT remains highly controversial and a contentious topic of discussion among health physicists, radiation biologists, and other radiological scientists. Indeed, it has been pointed out that the LNT has assumed the status of a paradigm, synonymous with an ideal, standard, or paragon or perhaps to some, a sacred cow. Reduced to its very basics, the LNT postulates that every increment of ionizing radiation dose, however small, carries with it a commensurate increase …

Interactive Learning Tools: Animating Statics, Nancy Hubing, David B. Oglesby, Timothy A. Philpot, Vikas Yellamraju, Richard H. Hall, Ralph E. Flori

Business and Information Technology Faculty Research & Creative Works

Computer-Based Modules for Engineering Instruction Must Be Concise, Flexible, Educational and Engaging in Order to Effectively Supplement Traditional Classroom Teaching Tools. a Computer Example that Takes More Time Than a Chalkboard Presentation is Not Likely to Be Useful in Today's Engineering Classroom. Flexible Navigation is Necessary So that the Instructor Can Quickly and Easily Respond to Student Questions. Useful Modules Must Also Improve Problem-Solving Skills or Clarify Troublesome Concepts in Order to Be Considered Worthy of Inclusion in the Limited Class Time Available. Finally, and Perhaps Most Importantly, Effective Computer-Based Modules Must Meet the Challenge of Holding the Student's Attention. …

Upper Spokane River Model: Boundary Conditions And Model Setup, 2001, Spencer Slominski, Robert Leslie Annear, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Washington Department of Ecology is interested in a water quality model for the Upper Spokane River system for use in developing Total Maximum Daily Loads (TMDLs). The goals of this modeling effort are to:

• Gather data to construct a computer simulation model of the Spokane River system including Long Lake Reservoir and the pools behind Nine Mile dam, Upper Falls dam and Upriver dam for 2001 based on the calibration conducted for 1991 and 2000 data sets, (Annear et al, 2001).

• Ensure that the model accurately represents the system hydrodynamics and water quality (flow, temperature, dissolved oxygen …

Load-Sensitive Transmission Power Control In Wireless Ad-Hoc Networks, Seung Jong Park, Raghupathy Sivakumar

Computer Science Faculty Research & Creative Works

Transmission power control in ad-hoc networks has hitherto been used only for achieving connectivity of networks. It has been implicitly assumed that the optimal throughput performance in ad-hoc networks can be achieved when using the minimum transmission power required to keep the network connected. However, in this paper we argue that such an assumption remains valid only under high node densities, which is not the characteristic of typical ad-hoc networks. Using both throughput and throughput per unit energy as the optimization criteria, we demonstrate that the optimal transmission power depends on several network characteristics such as the number of stations, …

Superfluidity In The Solar Interior: Implications For Solar Eruptions And Climate, Oliver Manuel, Barry W. Ninham, Stig Friberg

Chemistry Faculty Research & Creative Works

Efforts to understand unusual weather or abrupt changes in climate have been plagued by deficiencies of the standard solar model (SSM) [1]. Although it assumes that our primary source of energy began as a homogeneous ball of hydrogen (H) with a steady, well-behaved H-fusion reactor at its core, observations instead reveal a very heterogeneous, dynamic Sun. As examples, the upward acceleration and departure of H⁺ ions from the surface of the quiet Sun and abrupt climatic changes, including geomagnetic reversals and periodic magnetic storms that eject material from the solar surface are not explained by the SSM. The present …

Coexistence Of Ferromagnetic And Glassy States In Mechanically Milled Gdal2, C. Stark, P. M. Shand, T. M. Pekarek, D. Williams, R. Brown, Lanping Yue, Diandra Leslie-Pelecky

Diandra Leslie-Pelecky Publications

Measurements of DC susceptibility, AC susceptibility, and AC susceptibility with an applied DC bias field were performed on mechanically milled GdAl₂. A paramagnetic phase exists above a temperature T ≈ 140 K. However, there are significant deviations from the Curie-Weiss Law in this temperature regime, suggesting multiple magnetic components. Fits to the high temperature data show that two Curie-Weiss terms represent the data quite well. Below 140 K one of these magnetic components becomes ferromagnetic as indicated by a shoulder in the AC susceptibility and DC susceptibility data. This ferromagnetic component is suppressed by the application of sufficiently …

On Rank-Based Considerations For Generalized Linear Models And Generalized Estimating Equation Models, Diana R. Cucos

Dissertations

This study discusses rank-based robust methods for estimation of parameters and hypotheses testing in the generalized linear models (GLM) and generalized estimating equations (GEE) setting. The robust estimates are obtained by minimizing a Wilcoxon drop in dispersion function for linear or nonlinear regression models. In addition, diagnostic tools for outliers and influential observations are being developed. These models are generalizations of linear and nonlinear models. They allow for both nonlinear mean functions and heteroscedasticity of their random errors. This makes them quite useful in practice. Rank-based inference has been developed for linear models over the last thirty years. This inference …

Robust Residuals And Diagnostics In Autoregressive Time Series, Kirk W. Anderson

Dissertations

One of the goals of model diagnostics is outlier detection. In particular, we would like to use the residuals, appropriately standardized, to “flag” outliers. Hopefully, our (robust) procedure has yielded a fit that resists undue influence by outlying points, while simultaneously drawing attention to these interesting points via residual analysis. In this study we consider several different methods of standardizing the residuals resulting from autoregression. A large sample approximation for the variance of rank-based first order autoregressive time series residuals is developed. This provides studentized residuals, specific to the time series model and estimation procedure. Simulation studies are presented that …

Analysis Of Integrated Farming Systems In Eastern Nebraska, Lori A. Hoagland

School of Natural Resources: Dissertations, Theses, and Student Research

Agroecosystems in the U.S. are beset with social, ecological and environmental problems as large industrial farming methods are edging out small family-sized farms and replacing ecological services provided by biodiversity with synthetic inputs and practices. While many of the benefits of smaller diversified or integrated farming systems are well known, farm producers need a concrete model that shows how integration is possible and with what crops. The objective of this study was to investigate some of these supplemental farm activities, and identify and evaluate whether they were compatible given the time and resource constraints of a typical eastern Nebraska farm. …

Load Balancing And Congestion Avoidance Routing, Konstantinos N. Kokkinos

Dissertations

Today’s high speed backbone networks are expected to support a wide range of communication-intensive applications. One of the most important issues in Quality of Service (QoS) is efficient routing. Many QoS routing solutions have been published lately for different criteria of QoS requirements and resource constraints. In this dissertation we focus on the design of regular network topologies and suggest efficient routing schemes to reduce the probability of hot spot creation in the network. Furthermore, we provide a detection of congestion mechanism that reroutes traffic to maintain balancing with small communication cost. Several theoretical results relatively to network traffic balancing …

Geoelectrical Response Of An Aged Lnapl Plume: Implications For Monitoring Natural Attenuation, Douglas D. Werkema Jr.

Dissertations

The geoelectric stratigraphy at a site impacted with light non-aqueous phase liquids (LNAPLs) is investigated for its link to natural biodegradation, its contribution to the conductive model for aged (i.e. mature) LNAPL contaminated sites, and the relationship to the natural hydrologic regime. The highest conductivities (lowest resistivities) were observed in portions o f soils where LNAPL was in residual and free phase. Corroborating evidence from bacteria enumeration from soil close to the vertical resistivity probe (VRP) installations show orders-of-magnitude increase in both heterotrophic and oil degrading microbes at the depths where the conductivity was at a maximum. The coincidence o …

Data Mining With Newton's Method., James Dale Cloyd

Electronic Theses and Dissertations

Capable and well-organized data mining algorithms are essential and fundamental to helpful, useful, and successful knowledge discovery in databases. We discuss several data mining algorithms including genetic algorithms (GAs). In addition, we propose a modified multivariate Newton's method (NM) approach to data mining of technical data. Several strategies are employed to stabilize Newton's method to pathological function behavior. NM is compared to GAs and to the simplex evolutionary operation algorithm (EVOP). We find that GAs, NM, and EVOP all perform efficiently for well-behaved global optimization functions with NM providing an exponential improvement in convergence rate. For local optimization problems, we …