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1997

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Electron Acceleration By A Laser Wakefield In A Relativistically Self-Guided Channel, R. Wagner, Shouyuan Chen, Anatoly Maksimchuk, Donald P. Umstadter Apr 1997

Electron Acceleration By A Laser Wakefield In A Relativistically Self-Guided Channel, R. Wagner, Shouyuan Chen, Anatoly Maksimchuk, Donald P. Umstadter

Donald Umstadter Publications

Acceleration of electrons to relativistic energies by a multidimensional self-modulated laser wakefield is discussed. Above a power threshold, a relativistically self-guided channel from an intense ultrashort laser pulse (l∼4×1018 W/cm2, λ = 1 μm, τ = 400 fs) was found to increase the laser propagation distance, decrease the electron beam divergence, and increase the energy of the electrons. These electron beam effects occurred even though the propagation distance became significantly longer than the conventional dephasing length.

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Interactive Dsp Course Development/Teaching Environment, Chaouki T. Abdallah, Dalton Arantes, Gregory L. Heileman, Don R. Hush, Ramiro Jordan, Roberto Lotufo, Neeraj Magotra, Howard Pollard, Edl Schamiloglu, Robert Whitman Apr 1997

Interactive Dsp Course Development/Teaching Environment, Chaouki T. Abdallah, Dalton Arantes, Gregory L. Heileman, Don R. Hush, Ramiro Jordan, Roberto Lotufo, Neeraj Magotra, Howard Pollard, Edl Schamiloglu, Robert Whitman

Electrical & Computer Engineering Faculty Publications

The authors have developed an interactive environment for the creation and maintenance of dynamic, active multimedia-based teaching mechanisms. The environment is designed to be user-friendly and to facilitate the creation of educational material. This tool has already been used to create courses in multidimensional signal processing (MDSP) by researchers working together while geographically separated.

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Constraints From 26al Measurements On The Galaxy's Recent Global Star Formation Rate And Core-Collapse Supernovae Rate, F. X. Timmes, R. Diehl, Dieter H. Hartmann Apr 1997

Constraints From 26al Measurements On The Galaxy's Recent Global Star Formation Rate And Core-Collapse Supernovae Rate, F. X. Timmes, R. Diehl, Dieter H. Hartmann

Publications

Gamma rays from the decay of 26Al o†er a stringent constraint on the GalaxyÏs global star formation rate over the past million years, supplementing other methods for quantifying the recent Galactic star formation rate, such as equivalent widths of Ha emission. Advantages and disadvantages of using 26Al gamma-ray measurements as a tracer of the massive star formation rate are analyzed. Estimates of the Galactic 26Al mass derived from COMPTEL measurements are coupled with a simple, analytical model of the 26Al injection rate from massive stars and restrict the GalaxyÏs recent star formation rate to 5^4 yr~1. In addition, we show …

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Optical Rotation Curves Of Distant Field Galaxies: Sub-L, Systems, Nicole P. Vogt, Andrew C. Phillips, S. M. Faber, Jesús Gallego, Caryl Gronwall, R. Guzmán, Garth D. Illingworth, David C. Koo, James D. Lowenthal Apr 1997

Optical Rotation Curves Of Distant Field Galaxies: Sub-L, Systems, Nicole P. Vogt, Andrew C. Phillips, S. M. Faber, Jesús Gallego, Caryl Gronwall, R. Guzmán, Garth D. Illingworth, David C. Koo, James D. Lowenthal

Astronomy: Faculty Publications

Moderate-resolution spectroscopic observations from the Keck 10 m telescope are used to derive internal kinematics for eight faint disk galaxies in the fields flanking the Hubble Deep Field. The spectroscopic data are combined with high-resolution F814W Wide Field Planetary Camera 2 images from the Hubble Space Telescope that provide morphologies, scale lengths, inclinations, and orientations. The eight galaxies have redshifts 0.15 ≲ z ≲ 0.75, magnitudes 18.6 ≤ I ≤ 22.1, and luminosities -21.8 ≤ M ≤ -19.0 (H = 75 km s Mpc and q = 0.05). Terminal disk velocities are derived from the spatially resolved velocity profiles by …

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The Pacifican, April 10, 1997, University Of The Pacific Apr 1997

The Pacifican, April 10, 1997, University Of The Pacific

All Issues - Student Newspaper, The Pacifican, Pacific Weekly

No abstract provided.

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The Multicultural Vantage Program: A Model For Increasing Minority Enrollment In The Medical And Allied Health Fields, Odra W. Bradley Apr 1997

The Multicultural Vantage Program: A Model For Increasing Minority Enrollment In The Medical And Allied Health Fields, Odra W. Bradley

Different Perspectives on Majority Rules: 2nd Annual Conference (1997)

“The cost of attending colleges offering health professions is beyond the reach of al but a few of the underrepresented students being considered.”

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April 18, 1997 Cal Poly Report, Public Affairs Office Apr 1997

April 18, 1997 Cal Poly Report, Public Affairs Office

Cal Poly Report

No abstract provided.

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Empowering African American Students To Learn, Kimberly D. Ewing Apr 1997

Empowering African American Students To Learn, Kimberly D. Ewing

Different Perspectives on Majority Rules: 2nd Annual Conference (1997)

This presentation will encourage students to take African American courses and explore other cultures as well.

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Generalization Of The Bound State Model, Joseph Schechter, Masayasu Harada, Francesco Sannino, Herbert Weigel Apr 1997

Generalization Of The Bound State Model, Joseph Schechter, Masayasu Harada, Francesco Sannino, Herbert Weigel

Physics - All Scholarship

In the bound state approach the heavy baryons are constructed by binding, with any orbital angular momentum, the heavy meson multiplet to the nucleon considered as a soliton in an effective meson theory. We point out that this picture misses an entire family of states, labeled by a different angular momentum quantum number, which are expected to exist according to the geometry of the three-body constituent quark model (for N_C=3). To solve this problem we propose that the bound state model be generalized to include orbitally excited heavy mesons bound to the nucleon. In this approach the missing angular momentum …

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Interview With Barbara Ewing, Judy Carol Dankenbring, Barbara Ewing Apr 1997

Interview With Barbara Ewing, Judy Carol Dankenbring, Barbara Ewing

One-Room Schoolhouse Oral Histories

An interview with Barbara Ewing regarding her experiences in a one-room school house.

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Nathan Mueggenburg Of Godfrey, Ill. Goldwater Scholarship Awarded To Illinois Wesleyan, Bob Aaron Apr 1997

Nathan Mueggenburg Of Godfrey, Ill. Goldwater Scholarship Awarded To Illinois Wesleyan, Bob Aaron

News and Events (Discontinued Series)

No abstract provided.

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Newscast, April 18, 1997, Illinois State University, College Of Applied Science And Technology Apr 1997

Newscast, April 18, 1997, Illinois State University, College Of Applied Science And Technology

newsCAST

Newsletter of the Illinois State University College of Applied Science and Technology

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Crusader, April 18, 1997, College Of The Holy Cross Apr 1997

Crusader, April 18, 1997, College Of The Holy Cross

Student Newspapers

The student newspaper for the College of the Holy Cross in Worcester, Massachusetts. Articles include coverage of campus events and issues, sports, editorials and special features.

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University Of Montana Events Monday, April 21, Through Sunday, April 27, 1997, University Of Montana--Missoula. Office Of University Relations Apr 1997

University Of Montana Events Monday, April 21, Through Sunday, April 27, 1997, University Of Montana--Missoula. Office Of University Relations

University of Montana News Releases, 1928, 1956-present

No abstract provided.

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The Ucf Report, Vol. 19 No. 19, April 18, 1997, University Of Central Florida Apr 1997

The Ucf Report, Vol. 19 No. 19, April 18, 1997, University Of Central Florida

The UCF Report

Faculty and students were honored at the annual Founders Day celebration; Construction projects continue in race to keep pace with UCF's increase in students; New director selected for Library.

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Jeremy Katter Of Springfield, Ill. Goldwater Scholarship Awarded To Illinois Wesleyan Physics, Bob Aaron Apr 1997

Jeremy Katter Of Springfield, Ill. Goldwater Scholarship Awarded To Illinois Wesleyan Physics, Bob Aaron

News and Events (Discontinued Series)

No abstract provided.

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Physics & Math Major 2 Iwu Students Win Goldwater Scholarships, U.S. Supported Awards, Bob Aaron Apr 1997

Physics & Math Major 2 Iwu Students Win Goldwater Scholarships, U.S. Supported Awards, Bob Aaron

News and Events (Discontinued Series)

No abstract provided.

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Lanthorn, Vol. 31, No. 30, April 17, 1997, Grand Valley State University Apr 1997

Lanthorn, Vol. 31, No. 30, April 17, 1997, Grand Valley State University

Volume 31, July 18, 1996 - April 17, 1997

Lanthorn is Grand Valley State's student newspaper, published from 1968 to the present.

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Western News, April 17, 1997, Western Michigan University Apr 1997

Western News, April 17, 1997, Western Michigan University

Western News (1972-2018)

Story highlights: Scott selected as new dean of the Graduate College, Sky Broncos hope to fly high in national competition here, Bronco sculpture to be installed near fieldhouse, Nigerian doctor to present ethics center lecture at 'K’, Researchers team up with schools to improve sportsmanship, Landis earns awards for academic achievement, Gesink honored with award.

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Eastern Progress - 17 Apr 1997, Eastern Kentucky University Apr 1997

Eastern Progress - 17 Apr 1997, Eastern Kentucky University

Eastern Progress 1996-1997

No abstract provided.

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Two-Dimensional Analysis Of Natural Convection And Radiation In Utilidors, Paul W. Richmond Apr 1997

Two-Dimensional Analysis Of Natural Convection And Radiation In Utilidors, Paul W. Richmond

Engineering

Central heating plants are often used on large building complexes such as university campuses or military bases. Utilidors can be used to contain heat distribution lines and other utilities between a utility station and serviced buildings. Traditional thermal analysis of utilidors is one-dimensional, with heat transfer correlations used to estimate the effects of convection, radiation, and two-dimensional geometric effects. The expanding capabilities of computers and numerical methods suggest that more detailed analysis and possibly more energy-efficient designs could be obtained. This work examines current methods of estimating the convection and radiation that occur across an air space in square and …

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The Pan American (1997-04-17), Norma Castillo Apr 1997

The Pan American (1997-04-17), Norma Castillo

UTPA Archives - The Pan American Newspaper

45th Year, No. 28

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Equilibrium Structure And Dynamics Of Near-Earth Plasma Sheet During Magnetospheric Substorms, Lin Zhang Apr 1997

Equilibrium Structure And Dynamics Of Near-Earth Plasma Sheet During Magnetospheric Substorms, Lin Zhang

Physics

A magnetofrictional method and MHD simulation are used to study MHD equilibria and dynamic evolution of the Earth's magnetosphere during a substorm growth phase. I suggest that the new "entropy anti-diffusion instability" associated with plasma transport across field lines leads to an enhanced entropy gradient and accelerates the formation of a thin current sheet during the final substorm growth phase. Based upon the MHD simulations with a pressure diffusion term, I confirm that entropy anti-diffusion instability can lead to a very thin current sheet with $B\sb{z} < 0.5nT$ and thickness $<$1000km in the near-earth magnetotail ($x \sim -8$ to $-20R\sb{e}$) during the growth phase of substorm. The formation of the thin current sheet can explain the observed explosive growth phase of substorms. In the study of magnetotail equilibrium configurations, it is found that the profile of the magnetic field strength B$\sb{z}$ component in the equatorial plane is mainly determined by the entropy $S(A)\ (S = pV\sp\gamma)$ on magnetic flux tubes. I obtain self-consistent equilibria of the Earth's magnetosphere with very strong lobe fields and a monotonically increasing $B\sb{z}$ component towards the Earth. It is also confirmed that an enhancement of the lobe flux favors the formation of a current sheet during the early substorm growth phase. However, my results do not support the notion that a critical amount of the lobe flux is required for a collapse of the tail current sheet.

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The Universal Duty To Alleviate Inflicted Suffering: An Ethical Grounding For Siu's New Discipline Of Panetics, Russell Doyle Amerson Apr 1997

The Universal Duty To Alleviate Inflicted Suffering: An Ethical Grounding For Siu's New Discipline Of Panetics, Russell Doyle Amerson

Other

Dr. Ralph G. H. Siu has challenged the intellectual community with a call for a new academic discipline that he calls Panetics (from the Pali word paneti meaning 'to inflict'). Panetics is the study of humanly engendered suffering, its causes and methods of alleviation. Suffering is measured in units called dukkhas (from the Pali word dukkha meaning suffering), which are the product of the intensity of pain and the amount of time the pain is endured. The result will be in terms of units of suffering, i.e. the dukkha. Dr. Siu has argued that this new academic discipline is not …

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Uas Academic Catalog 1997/1998, N/A N/A Apr 1997

Uas Academic Catalog 1997/1998, N/A N/A

UAS Academic Catalogs (1988/89-2010/11)

No abstract provided.

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Snow And Ice Thickness Distributions In The South Polar Pacific Ocean, Ute Adolphs Apr 1997

Snow And Ice Thickness Distributions In The South Polar Pacific Ocean, Ute Adolphs

Theses (Unassigned)

Two sets of snow and ice thickness data of antarctic sea ice are presented in this study: drilling profiles on individual sea ice floes and spatially more extensive shipboard observations are investigated in order to reveal spatial and temporal characteristics of sea ice. The data were acquired between 1993 and 1995 in the Ross and the Amundsen/Bellinghausen Seas, two different regions of the south polar Pacific Ocean. Sea ice characteristics as well as their spatial distribution and temporal evolution are derived from the data sets. Strong regional trends are observed in ice thickness distributions of the drilling data. A spatial …

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Extent, Timing, And Paleogeographic Significance Of Multiple Pleistocene Glaciations In The Bering Strait Region, Patricia Anne Heiser Apr 1997

Extent, Timing, And Paleogeographic Significance Of Multiple Pleistocene Glaciations In The Bering Strait Region, Patricia Anne Heiser

Theses (Unassigned)

This study utilizes a multidisciplinary approach to the investigation of the extent, timing, and potential effects of repeated Pleistocene glaciation in Bering Strait region. A major focus of this study was directed toward testing the hypothesis that a continental-scale ice sheet existed in Beringia during the Late Wisconsin glacial period. Satellite synthetic aperture radar (SAR) imagery was used to compile a map of glacial moraines in Chukotka, Russia, and to attempt preliminary correlations with the glacial record in Alaska. Geophysical modelling of the solid-earth response to postulated glacial loading, and the reconstruction of regional snowline were combined with the results …

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Thermally Enhanced Bioventing Of Petroleum Hydrocarbons In Cold Regions, Dennis M. Filler Apr 1997

Thermally Enhanced Bioventing Of Petroleum Hydrocarbons In Cold Regions, Dennis M. Filler

Theses (Unassigned)

Petroleum-based contamination of the environment has and will likely continue to be a problem as long as oil and natural gas supply much of the world energy demands. In cold regions, where vast quantities of these fuels are extracted and used, climate and frozen soils limit remedial efforts to a few technologies. Bioventing has shown promise as a viable method for the remediation of spilled petroleum-based fuels in cold regions. An in situ study of bioventing with soil warming was conducted at a Fairbanks, Alaska site. The main purpose of this research effort was to compare the effectiveness of thermal …

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Microbial Ecology And Long-Term Persistence Of Crude Oil In A Taiga Spruce Forest, Jon Eric Lindstrom Apr 1997

Microbial Ecology And Long-Term Persistence Of Crude Oil In A Taiga Spruce Forest, Jon Eric Lindstrom

Theses (Unassigned)

The microbial ecology of a 1976 experimental crude oil spill in an Alaskan taiga black spruce forest was investigated in this study. Substantial oil residue remained in the soil, and several microbial parameters showed evidence of long-term oiling effects. Overall, the data suggest that the surviving community in the oiled plot has shifted toward using oil C for growth. Numbers of hydrocarbon degrading microbes, and specific hydrocarbon mineralization potentials, were significantly elevated in the oiled (OIL) plot compared to an adjacent oil-free, reference (REF) plot. Glutamate mineralization potentials and soil C mineralization, on the other hand, were not different between …

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Proximate And Ultimate Control Of Reproductive Effort In Northern Shovelers (Anas Clypeata) Nesting At Minto Flats, Alaska, Margaret Christine Maccluskie Apr 1997

Proximate And Ultimate Control Of Reproductive Effort In Northern Shovelers (Anas Clypeata) Nesting At Minto Flats, Alaska, Margaret Christine Maccluskie

Theses (Unassigned)

The purpose of this study was to examine factors that influence reproductive effort of female Northern Shovelers (Anas clypeata) nesting at Minto Flats, AK during summer 1991-1993. I investigated the importance of endogenous nutrient reserves to females during egg production and examined changes in organ weights and intestine lengths through the reproductive cycle. Changes in organ weights and intestine length were similar to those of shovelers nesting in Manitoba. Females used neither somatic lipid reserves, protein reserves, nor mineral reserves to produce eggs. Individual variation in somatic lipid reserves was explained by body size and nest initiation date, while variation …

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