Physical Sciences and Mathematics Commons^™

Identification Of Spatial And Temporal Patterns Of Secondary Succession Changes In Altamira, Brazil: Integrating Remote Sensing And Gis Technology, Hui Li

All-Inclusive List of Electronic Theses and Dissertations

There has been extensive use of remote sensing to study secondary succession of moist tropical forests in the Amazon Basin. However, scientists have not totally understood the dynamic processes of secondary succession of Amazon forests. A lack of consensus remains about what is the best approach for biomass estimation in the Amazon Basin using remotely sensed data. It is not clear which spectral wavelength bands have the best relationship with biomass values and what are the specific relationships between biomass and TM satellite radiance. The strategies in this research, based on analysis of detailed ground-based data and satellite TM image …

The Effect Of Prescribed Burns On Cation Exchange Capacity In An Oak Savanna, Christopher Michael Gentry

All-Inclusive List of Electronic Theses and Dissertations

The Indiana Department of Natural Resources estimates that fire-maintained, tallgrass savannas once covered approximately 15% oflndiana. During the 1800's, settlers cleared savannas for their rich soils, which are well suited for agricultural use, and fire was suppressed from the remaining savannas because of the threat to farmland. Today, prescribed bums are being used in savannas as a management tool to reduce competition from non-native species, encourage community density, and promote patch dynamics. This research examines how fire affects Cation Exchange Capacity (CEC) in post fire soil samples. CEC is an important soil characteristic that helps to describe soil fertility. With …

New Studies Initiated By The U.S. Geological Survey: Effects Of Nutrient Enrichment On Stream Ecosystems, Mark D. Munn, Pixie A. Hamilton

United States Geological Survey: Publications

In 2001, the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Program began an intensive study of nutrient enrichment—elevated concentrations of nitrogen and phosphorus— in streams in five agricultural basins across the Nation (see map, p. 2). This study is providing nationally consistent and comparable data and analyses of nutrient conditions, including how these conditions vary as a result of natural and human-related factors, and how nutrient conditions affect algae and other biological communities. This information will benefit stakeholders, including the U.S. Environmental Protection Agency (USEPA) and its partners, who are developing nutrient criteria to protect the aquatic health of streams …

“Don’T Tell Me, I’Ll Find Out”: Robert Karplus—A Science Education Pioneer, Robert Fuller

Robert G. Fuller Publications

Robert Karplus (1927–90), who began his career as a brilliant theoretical physicist, switched to science education in the early 1960s. He made many substantial contributions to this field in addition to developing a complete K–6 hands-on science curriculum. Karplus provided his curriculum with a sound epistemological foundation, based on the work of Piaget. He developed an effective classroom teaching strategy, the learning cycle. He and his team used a scientific approach to curriculum development. They focused on teacher development. Karplus was committed to science for ALL students. Through science activities he sought to share the joy of discovery. A recent …

Flocking Over 3d Terrain, Joel Gompert

School of Computing: Technical Reports

A method is presented for animating herds of animals that can follow terrain while being efficient enough to run in real-time. This method involves making simple modifications to Reynolds’ agent-based flocking algorithm. The modifications use only local properties of the terrain, and thus have low complexity. This method focuses on using terrain that can be described as an elevation grid, but it may be extendible to arbitrary terrain. The flocking algorithm with these modifications produces naturally behaving herds that follow the terrain. They will swerve around hills and attempt to follow paths that reduce energy expenditure. The terrain-following rule added …

Reviewed Work(S): Electronic Tagging And Tracking In Marine Fisheries., David W. Kerstetter

Marine & Environmental Sciences Faculty Articles

No abstract provided.

Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor

Computer Science Faculty Publications and Presentations

In this paper we design a proportional-period optimal controller for allocating CPU to real rate multimedia applications on a general-purpose computer system. We model this computer system problem in to state space form. We design a controller based on dynamic optimization LQR tracking techniques to minimize short term and long term time deviation from the current time stamp and also CPU usage. Preliminary results on an experimental set up are encouraging.

Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A. R. Frederickson, John R. Dennison

All Physics Faculty Publications

Improved experimental methods are discussed for laboratory measurement of conductivity and electric field in insulating spacecraft material intended for space radiation and plasma environments. These measurement techniques investigate the following features: 1) measurements of conductivity are up to four orders of magnitude smaller than those determined by existing standard methods. 2) Conductivity is altered as radiation accumulates and trapping states fill with electrons. 3) With intense kiloelectronvolt electron irradiation, electrons are continually emitted for hours from the irradiated surface after the irradiation ceases. 4) Charging induced by electron irradiation is strongly modified by the electron-hole pairs that the irradiation generates …

A Modeling Experiment On The Grounding Of An Ice Shelf In The Central Arctic Ocean During Mis 6, Martin Jakobsson, M Siegert, Mark Paton

Center for Coastal and Ocean Mapping

High-resolution chirp sonar subbottom profiles from the Lomonosov Ridge in the central Arctic Ocean, acquired from the Swedish icebreaker Oden in 1996, revealed large-scale erosion of the ridge crest down to depths of 1000 m below present sea level [Jakobsson, 1999]. Subsequent acoustic mapping during the SCICEX nuclear submarine expedition in 1999 showed glacial fluting at the deepest eroded areas and subparallel ice scours from 950 m water depth to the shallowest parts of the ridge crest [Polyak et al., 2001]. The directions of the mapped glaciogenic bed-forms and the redeposition of eroded material on the Amerasian side of the …

Acknowledgements, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Age, Growth And The Annual Cycles Of Lipogenesis And Reproduction Of Acanthurus Bahianus In Southeastern Florida, Stacy M. Wolfe

HCNSO Student Theses and Dissertations

The ocean surgeon, Acanthurus bahianus, is a coral reef fish inhabiting the tropical and subtropical waters of the western Atlantic, including southeastern Florida. This study was a 23-month analysis of the reproductive cycle correlated with the annual build up and depletion of fat reserves in the fish. In addition, an age and growth analysis of this species was conducted. A total of 507 fish were analyzed for length, weight, gonad weight and fat body weight. 478 were aged by microscopic examination of the transverse section of the sagittae otolith. The von Bertalannfy growth equation was used to determine length at …

Pyro: A Python-Based Versatile Programming Environment For Teaching Robotics, D. Blank, D. Kumar, Lisa A. Meeden, H. Yanco

Computer Science Faculty Works

In this article we describe a programming framework called Pyro, which provides a set of abstractions that allows students to write platform-independent robot programs. This project is unique because of its focus on the pedagogical implications of teaching mobile robotics via a top-down approach. We describe the background of the project, its novel abstractions, its library of objects, and the many learning modules that have been created from which curricula for different types of courses can be drawn. Finally, we explore Pyro from the students' perspective in a case study.

Notes From The Director, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Mcnair Scholars Program, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Message From The Provost, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Full Issue, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Effect Of Heavy Metals On Bacteria, Elena Vratonjic

Theses and Dissertations

Heavy metals have become devastating environmental contaminants due to their widespread use in the manufacture of electronics, plastics, batteries and dyes. The discharge of heavy metals into the environment has caused concern about their effects on the ecosystem. Many metals are essential for growth in small amounts. However, at higher concentrations heavy metals are toxic because they bind to organic compounds. This accounts for their effects on some important parts of the cell structure, like their ability to denature protein molecules. The initial objective of this study was to find out the growth rate of E.coli and M.roseus in the …

Enabling Computer Decisions Based On Eeg Input, Benjamin J. Culpepper, Robert M. Keller

All HMC Faculty Publications and Research

Multilayer neural networks were successfully trained to classify segments of 12-channel electroencephalogram (EEG) data into one of five classes corresponding to five cognitive tasks performed by a subject. Independent component analysis (ICA) was used to segregate obvious artifact EEG components from other sources, and a frequency-band representation was used to represent the sources computed by ICA. Examples of results include an 85% accuracy rate on differentiation between two tasks, using a segment of EEG only 0.05 s long and a 95% accuracy rate using a 0.5-s-long segment.

Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A Robb Frederickson, Jr Dennison

Journal Articles

Improved experimental methods are discussed for laboratory measurement of conductivity and electric field in insulating spacecraft material intended for space radiation and plasma environments. These measurement techniques investigate the following features: 1) Measurements of conductivity are up to four orders of magnitude smaller than those determined by existing standard methods. 2) Conductivity is altered as radiation accumulates and trapping states fill with electrons. 3) With intense keV electron irradiation, electrons are continually emitted for hours from the irradiated surface after the irradiation ceases. 4) Charging induced by electron irradiation is strongly modified by the electron-hole pairs that the irradiation generates …

Global Solutions To The Lake Equations With Isolated Vortex Regions, Chaocheng Huang

Mathematics and Statistics Faculty Publications

The vorticity formulation for the lake equations in R² is studied.

Comparisons Of Electron Fluxes Measured In The Crustal Fields At Mars By The Mgs Magnetometer/Electron Reflectometer Instrument With A B Field-Dependent Transport Code, Michael W. Liemohn, David L. Mitchell, Andrew F. Nagy, Jane L. Fox, Tamara W. Reimer, Yingjuan J. Ma

Physics Faculty Publications

We compare Mars Global Surveyor (MGS) magnetometer/electron reflectometer data with results from a B field–dependent kinetic transport code for ‘‘superthermal’’ electrons. The photoelectrons created on crustal field loops, when they are on the dayside, allow for the exploration of the magnetic topology and the upper atmospheric density structure. A case study of a typical orbit of the MGS satellite through the strong crustal field region in the southern hemisphere of Mars is examined. The results indicate that the low solar wind dynamic pressure during the selected orbit allowed for the expansion of the crustal field line to relatively high altitudes. …

Fabrication And Characterization Of N-Zno/P-Algan Heterojunction Light-Emitting Diodes On 6h-Sic Substrates, Ya I. Alivov, E. V. Kalinina, A. E. Cherenkov, David C. Look, B. M. Ataev, A. K. Omaev, M. V. Chukichev, D. M. Bagnall

Physics Faculty Publications

We report on the fabrication of n-ZnO/p-AlGaN heterojunction light-emitting diodes on 6H-SiC substrates. Hydride vapor phase epitaxy was used to grow p-type AlGaN, while chemical vapor deposition was used to produce the n-type ZnO layers. Diode-like, rectifying I-V characteristics, with threshold voltage ~3.2 V and low reverse leakage current ~10^-7 A, are observed at room temperature. Intense ultraviolet emission with a peak wavelength near 389 nm is observed when the diode is forward biased; this emission is found to be stable at temperatures up to 500 K and shown to originate from recombination within the ZnO.

Development And Optimization Of Hplc-Icpms For The Determination Of Iodine Speciation In Groundwater, Yun Qiu

All-Inclusive List of Electronic Theses and Dissertations

High performance liquid chromatography has been coupled with online inductively coupled plasma mass spectrometry detection for the determination of iodine speciation in drinking and groundwaters. Using ion exchange chromatography, the method is applied to quantify the concentrations of iodine species in groundwaters. The HPLC-UV detection was used first to examine the separation efficiency of the HPLC method. The limit of quantification was obtained for the HPLC-UV analysis. Direct ICPMS analysis of iodine species has been validated and optimized using an HC03"/C03 2 - aqueous solvent. HPLC was then interfaced to the ICPMS T-shape connection to allow online addition of internal …

The Role Of Facial Pits In The Thermoregulatory Behavior Of Pitvipers (Viperidae: Crotalinae) Behavioral, Ecological And Phylogenetic Perspectives, Aaron R. Krochmal

All-Inclusive List of Electronic Theses and Dissertations

Pitvipers (Viperidae: Crotalinae) possess unique sensory organs, the facial pits, capable of sensing subtle fluctuations in thermal radiation. Prey acquisition has long been regarded as the sole function of the facial pits. However, the ability to sense thermal radiation could also direct thermoregulatory behavior by remotely sensing nearby surface temperatures. Using a series ofbehavioral arenas of varying spatial complexity and ecological relevance, I surveyed the ability of western diamondback rattlesnakes (Crotalus atrox) to direct successful thermoregulatory movements with either functional or disabled facial pits. I found that western diamondback rattlesnakes could base thermoregulatory decisions on thermal radiation cues when their …

Biological Permanent Magnets, Richard B. Frankel

Physics

Magnetotactic bacteria orient and migrate along magnetic field lines. Each cell is essentially a self-propelled magnetic dipole. The magnetic properties of these bacteria have been determined by a variety of techniques, including pulsed hysteresis measurements on single cells.

Objectivity, Information, And Maxwell's Demon, Steven Weinstein

Dartmouth Scholarship

This paper examines some common measures of complexity, structure, and information, with an eye toward understanding the extent to which complexity or information‐content may be regarded as objective properties of individual objects. A form of contextual objectivity is proposed which renders the measures objective, and which largely resolves the puzzle of Maxwell's Demon.

Geophysical Characterization Of A Former Refinery Site, Kalamazoo, Michigan, Baraka Damas Kinabo

Masters Theses

Lakeside, a former refinery site, in Kalamazoo, Michigan, is contaminated with hydrocarbon products. The contamination resulted from the refining and storage activities that took place at the site for over 50 years. The contamination is scattered in isolated pockets.

In an attempt to better define the contamination zones and therefore assist the remediation efforts, this study uses shallow geophysical methods including Electromagnetic induction using the EM 31 system, Magnetic, Ground Penetrating Radar (GPR), and Resistivity methods. The hand auger was used to further characterize some EM 31 anomalies. The EM 31 conductivity results show elevated values resulting from the biodegradation …

Optimization And Feedback Control Of Constrained Parabolic Systems Under Uncertain Perturbations, Boris S. Mordukhovich, Ilya Shvartsman

Mathematics Research Reports

This paper concerns a minimax control design problem for a class of parabolic systems with nonregular boundary conditions and uncertain distributed perturbations under pointwise control and state constraints. We deal with boundary controllers acting through Dirichlet boundary conditions that are the most challenging for the parabolic dynamics.

Modelling Growth And Testing Of Multilayer Cavity Structures Incorporating Birefringent Materials, Nour-Eddine El Khachia

Masters

A simple one-dimensional photonic bandgap structure, which is also known as a Fabry-Perot Microcavity (FPM) structure was studied theoretically and experimentally. In particular this project addressed introducing an optically birefringent material in the cavity. This FPM consists of two grown regular Distributed Bragg Reflector (DBR) mirrors that can be put together as a sandwich with a space between them, which will lead to the creation of the desired cavity. Each mirror, or one-dimensional dielectric stack structure, was grown using the Vacuum Evaporation Technique and consists of multiple layers of alternating high-and low-refractive index dielectric materials arranged periodically. The project covers …

Viewer-Based Directional Querying For Mobile Applications, Keith Gardiner, James Carswell

Conference papers

With the steady and fast advancements in the integration of geographic information systems and mobile location-based services, interest in exploiting this technology for Cultural Heritage (CH) data sharing has become apparent. In this area there has been an increasing need to integrate positional information with non-positional data and add a spatial dimension to the definition of a users “context”. In this paper we describe an implementation of a viewer-based directional query processor that operates on an Oracle Spatial database. The spatial position and orientation are taken from the viewer’s perspective. Using this frame of reference a view-port is defined in …