Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

1999

Utah State University

Discipline
Keyword
Publication
Publication Type

Articles 1 - 30 of 72

Full-Text Articles in Physical Sciences and Mathematics

Video And Photometric Observations Of A Sprite In Coincidence With A Meteor-Triggered Jet Event, D. M. Suszcynsky, R. Strabley, R. Roussel-Dupre, E. M.D. Symbalisty, R. A. Armstrong, W. A. Lyons, Michael J. Taylor Dec 1999

Video And Photometric Observations Of A Sprite In Coincidence With A Meteor-Triggered Jet Event, D. M. Suszcynsky, R. Strabley, R. Roussel-Dupre, E. M.D. Symbalisty, R. A. Armstrong, W. A. Lyons, Michael J. Taylor

All Physics Faculty Publications

Video and photometric observations of a meteor-triggered “jet” event in association with the occurrence of a sprite were collected during the SPRITES '98 campaign. The event raises interest in the question of possible meteoric triggering of upper atmospheric transients as originally suggested by Muller [1995]. The event consisted of three stages: (1) the observation of a moderately bright meteor, (2) the development of a sprite in the immediate vicinity of the meteor as the meteor reached no lower than ∼70 km altitude, and (3) a slower-forming jet of luminosity that appeared during the late stages of the sprite and propagated …


Environmental Assessment, Decision Record, And Finding Of No Significant Impact For The Ixc Communications, Inc.'S Proposed Fiber Optic Telecommunications System, Denver, Colorado, To Salt Lake City, Utah, U.S. Department Of The Interior, Bureau Of Land Management Nov 1999

Environmental Assessment, Decision Record, And Finding Of No Significant Impact For The Ixc Communications, Inc.'S Proposed Fiber Optic Telecommunications System, Denver, Colorado, To Salt Lake City, Utah, U.S. Department Of The Interior, Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

IXC proposes to install and operate a telecommunications system from Denver, Colorado, to Salt Lake City, Utah, to provide service to these and other western cities. The approximately 611-mile long cable would cross 116 miles of federal land administered by the BLM (all within Wyoming), 1 mile of National Forest lands administered by the Forest Service (all within Utah), and 494 miles of state, county, municipal, and private lands. Three 1.9-inch and three 2.4-inch high-density polyethylene conduits would be installed simultaneously and a fiber optic cable would be installed in one conduit; the other conduits would be used for future …


1991-1992 & 1996 Utah Usage Of Ems Services By Children: Year Iii Research Report, Intermountain Injury Control Research Center, U.S. Department Of Commerce Nov 1999

1991-1992 & 1996 Utah Usage Of Ems Services By Children: Year Iii Research Report, Intermountain Injury Control Research Center, U.S. Department Of Commerce

All U.S. Government Documents (Utah Regional Depository)

This study examined how Utah children used emergency medical services (EMS) and related hospital care in 1991-1992. The EMS and hospital records were linked using special software (probabilistic linkage) . The principal findings of the study concerned the care of young children less than 5 years of age. They received fewer procedures prior to being transported to a hospital and required more time at the scene for assessment. Some interventions such as splinting of fractured arms prior to transport to a hospital were related to reduced hospital charges. Ambulance and hospital charges for children were estimated to by $35,000,000 not …


Conformal Actions In Any Dimension, Andre Wehner, James Thomas Wheeler Sep 1999

Conformal Actions In Any Dimension, Andre Wehner, James Thomas Wheeler

All Physics Faculty Publications

Biconformal gauging of the conformal group gives a scale-invariant volume form, permitting a single form of the action to be invariant in any dimension. We display several 2n-dimensional scale-invariant polynomial actions and a dual action. We solve the field equations for the most general action linear in the curvatures for a minimal torsion geometry. In any dimension n > 2, the solution is foliated by equivalent n-dimensional Ricci-flat Riemannian space-times, and the full 2n-dimensional space is symplectic. Two fields defined entirely on the Riemannian submanifolds completely determine the solution: a metric eμα, and …


Effects Of The Vertical Plasma Drift Velocity On The Generation And Evolution Of Equatorial Spread F, Bela G. Fejer, L. Scherliess, E. R. De Paula Sep 1999

Effects Of The Vertical Plasma Drift Velocity On The Generation And Evolution Of Equatorial Spread F, Bela G. Fejer, L. Scherliess, E. R. De Paula

Bela G. Fejer

We use radar observations from the Jicamarca Observatory from 1968 to 1992 to study the effects of the F region vertical plasma drift velocity on the generation and evolution of equatorial spread F. The dependence of these irregularities on season, solar cycle, and magnetic activity can be explained as resulting from the corresponding effects on the evening and nighttime vertical drifts. In the early night sector, the bottomside of the F layer is almost always unstable. The evolution of the unstable layer is controlled by the history of the vertical drift velocity. When the drift velocities are large enough, the …


Final Intrinsic Remediation, Engineering Evaluation/Cost Analysis Addendum For Ust Site 870, Hill Air Force Base, Ogden, Utah, Parsons Engineering Science, Inc. Sep 1999

Final Intrinsic Remediation, Engineering Evaluation/Cost Analysis Addendum For Ust Site 870, Hill Air Force Base, Ogden, Utah, Parsons Engineering Science, Inc.

All U.S. Government Documents (Utah Regional Depository)

This report was prepared for the Air Force Center for Environmental Excellence (AFCEE) by Parsons Engineering Science, Inc. (parsons ES) as an update to the Final Intrinsic Remediation Engineering Evaluation/Cost Analysis (EE/CA) for Underground Storage Tank (UST) Site 870, Hill Air Force Base (AFB), Utah (parsons ES, 1995). The EE/CA was conducted to evaluate the use of intrinsic remediation with long-term monitoring (LTM) for remediation of fuel hydrocarbon contamination dissolved in groundwater at UST Site 870. This update summarizes the results of the third sampling event performed as part of longterm groundwater monitoring at the site. This sampling was conducted …


Equatorial And Low Latitude Thermospheric Winds: Measured Quiet Time Variations With Season And Solar Flux From 1980 To 1990, M. A. Biondi, S. Y. Sazykin, Bela G. Fejer, J. W. Meriwether, C. G. Fesen Aug 1999

Equatorial And Low Latitude Thermospheric Winds: Measured Quiet Time Variations With Season And Solar Flux From 1980 To 1990, M. A. Biondi, S. Y. Sazykin, Bela G. Fejer, J. W. Meriwether, C. G. Fesen

Bela G. Fejer

Thermospheric winds have been systematically determined at Arequipa, Peru, and Arecibo, Puerto Rico, from Fabry-Perot interferometer measurements of Doppler shifts in the nightglow 630 nm line. The wind databases (1983 – 1990 at Arequipa and 1980 – 1990 at Arecibo) have been edited to eliminate measurements during geomagnetically disturbed conditions, then sorted by season and solar flux level. Following this, they were averaged to obtain the climatological behavior of the nighttime wind variations at the two locations. A new averaging technique, multivariate regression analysis, has been applied to the data, and the results compared to our prior binning averages. The …


Natural Resources Conservation Laws A Report On 17 States And Their Selected Counties And Townships, Huong N. Tran, Liu-Hsiung Chuang, Carolyne L. Guss, Resource Economics And Social Sciences Division, Natural Resources Conservation Service, U.S. Department Of Agriculture Jul 1999

Natural Resources Conservation Laws A Report On 17 States And Their Selected Counties And Townships, Huong N. Tran, Liu-Hsiung Chuang, Carolyne L. Guss, Resource Economics And Social Sciences Division, Natural Resources Conservation Service, U.S. Department Of Agriculture

All U.S. Government Documents (Utah Regional Depository)

Laws are social institutions that guide social functions, declare social programs, and even project the visions of a governed society. In a democracy like the United States of America, laws exist at every level of government. Federal, state, and local agencies that have related missions work together as partners, and their staffs need to understand the legal requirements and limitations to better serve the constituents. Private citizens can also benefit from being aware of the laws of other jurisdictions that might serve as models for improving their laws and regulations. With this awareness the public spirit can be enhanced and …


Natural Resources Conservation Laws: A Report On 17 States And Their Selected Counties And Townships, Huong N. Tran, Liu-Hsiung Chuang, Carolyne L. Guss, Resource Economics And Social Sciences Division, Natural Resources Conservation Service, U.S. Department Of Agriculture Jul 1999

Natural Resources Conservation Laws: A Report On 17 States And Their Selected Counties And Townships, Huong N. Tran, Liu-Hsiung Chuang, Carolyne L. Guss, Resource Economics And Social Sciences Division, Natural Resources Conservation Service, U.S. Department Of Agriculture

All U.S. Government Documents (Utah Regional Depository)

Laws are social institutions that guide social functions, declare social programs, and even project the visions of a governed society. In a democracy like the United States of America, laws exist at every level of government. Federal, state, and local agencies that have related missions work together as partners, and their staffs need to understand the legal requirements and limitations to better serve the constituents. Private citizens can also benefit from being aware of the laws of other jurisdictions that might serve as models for improving their laws and regulations. With this awareness the public spirit can be enhanced and …


Criteria For Elves And Sprites On Schumann Resonance Observations, E. W. Huang, E. R. Williams, R. Boldi, S. Heckman, W. Lyons, Michael J. Taylor, C. Wong, T. Nelson Jul 1999

Criteria For Elves And Sprites On Schumann Resonance Observations, E. W. Huang, E. R. Williams, R. Boldi, S. Heckman, W. Lyons, Michael J. Taylor, C. Wong, T. Nelson

All Physics Faculty Publications

Ground flashes with positive polarity associated with both sprites and elves excite the Earth's Schumann resonances to amplitudes several times greater than the background resonances. Theoretical predictions for dielectric breakdown in the mesosphere are tested using ELF methods to evaluate vertical charge moments of positive ground flashes. Comparisons of the measured time constants for lightning charge transfer with the electrostatic relaxation time at altitudes of nighttime sprite initiation (50–70 km) generally validate the electrostatic assumption in predictions made initially by Wilson [1925]. The measured charge moments (Q dS = 200–2000 C-km) are large in comparison with ordinary negative lightning but …


Rare, Imperiled, And Recently Extinct Or Extirpated Mollusks Of Utah: A Literature Review, George V. Oliver, William R. Bosworth, Iii, State Of Utah Department Of Natural Resources Jun 1999

Rare, Imperiled, And Recently Extinct Or Extirpated Mollusks Of Utah: A Literature Review, George V. Oliver, William R. Bosworth, Iii, State Of Utah Department Of Natural Resources

All U.S. Government Documents (Utah Regional Depository)

About 139 species of mollusks are known to occur, or within historical times to have occurred, in Utah. The number of known Utah mollusks is not fixed and can be expected to continue to change, increasing as new molluscan discoveries are made in Utah and possibly decreasing as taxonomic revisions change our concept of how many valid mollusk species exist. This report represents one of the end products of a review of literature—published journal articles and books as well as unpublished agency reports—dealing with mollusks in Utah. The goals of this review were to determine (1) which species have been …


Final Environmental Impact Statement: Ferron Natural Gas Project, United States Department Of The Interior, Bureau Of Land Management, Utah, Usda Forest Service, Utah Division Of Oil, Gas, And Mining Jun 1999

Final Environmental Impact Statement: Ferron Natural Gas Project, United States Department Of The Interior, Bureau Of Land Management, Utah, Usda Forest Service, Utah Division Of Oil, Gas, And Mining

Elusive Documents

Anadarko Petroleum Corporation, Chandler and Associates, LLC, and Texaco Exploration and Production, Inc. propose to develop two separate areas northeast and southwest of Price, Utah and extract natural gas. Questar Pipeline Company proposes to develop a new natural gas transmission pipeline as part of the Proposed Action. With the pipeline corridor, the Proposed Action encompasses a total of about 111 ,781 acres. The developments would involve drilling a maximum of 285 natural gas wells on Federal, State and private lands, constructing roads and gathering pipelines for natural gas and produced water, drilling wells for disposing of produced water, and construction …


A Social Analysis Of Grazing Management On National Forest Lands: A Case Study In Catron County, New Mexico, Alexis S. Watts May 1999

A Social Analysis Of Grazing Management On National Forest Lands: A Case Study In Catron County, New Mexico, Alexis S. Watts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The rural west in this country faces increased national pressure concerning the management of natural resources on public lands. Issues regarding natural resource management are becoming more important as they continue to affect rural communities and capture the attention of a variety of interest groups. Natural resource managers are increasingly required to consider social dimensions of resource use and management. Lack of consideration in these areas can lead to dissatisfied, and even hostile, local residents and interest groups. Often land managers face criticism from many groups at once as a result of management decisions.

This study analyzed a particular resource …


The Role Of Iron And Reactive Oxygen Species In Particulate Air Pollution-Dependent Biochemical And Biological Activities, Kevin Richard Smith May 1999

The Role Of Iron And Reactive Oxygen Species In Particulate Air Pollution-Dependent Biochemical And Biological Activities, Kevin Richard Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particulate air pollution is known to exacerbate respiratory diseases, such as asthma and chronic obstructive pulmonary disease, in humans. It has been proposed that transition meta ls from inhaled particles may play a role in this exacerbation by generating radical species leading to damage in the lungs.

The aim of this research was to determine the role that iron from particulate air pollution played in the generation of reactive oxygen species and subsequently the induction of inflammatory mediators in cells in culture. The production of reactive oxygen species by particulate air pollution was found to be dependent on the mobilization …


Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca May 1999

Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cultures. The amo genes have excellent potential as molecular markers; since AMO is only found in the AOB and is essential for their metabolism, …


Vessiot: A Maple Package For Varational And Tensor Calculus In Multiple Coordinate Frames, Charles E. Miller May 1999

Vessiot: A Maple Package For Varational And Tensor Calculus In Multiple Coordinate Frames, Charles E. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Maple V package Vessiot is an extensive set of procedures for performing computations in variational and tensor calculus. Vessiot is an extension of a previous package, Helmholtz, which was written by Cinnamon Hillyard for performing operations in the calculus of variations. The original set of commands included standard operators on differential forms, Euler-Lagrange operators, the Lie bracket operator, Lie derivatives, and homotopy operators. These capabilities are preserved in Vessiot, and enhanced so as to function in a multiple coordinate frame context. In addition, a substantial number of general tensor operations have been added to the package. These include standard …


Construction And Analysis Of A Family Of Numerical Methods For Hyperbolic Conservation Laws With Stiff Source Terms, Cinnamon Hillyard May 1999

Construction And Analysis Of A Family Of Numerical Methods For Hyperbolic Conservation Laws With Stiff Source Terms, Cinnamon Hillyard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Numerical schemes for the partial differential equations used to characterize stiffly forced conservation laws are constructed and analyzed. Partial differential equations of this form are found in many physical applications including modeling gas dynamics, fluid flow, and combustion. Many difficulties arise when trying to approximate solutions to stiffly forced conservation laws numerically. Some of these numerical difficulties are investigated.

A new class of numerical schemes is developed to overcome some of these problems. The numerical schemes are constructed using an infinite sequence of conservation laws.

Restrictions are given on the schemes that guarantee they maintain a uniform bound and satisfy …


Evaluating Snowmelt Runoff, Infiltration, And Erosion In A Sagebrush-Steppe Ecosystem, Eric K. Duffin May 1999

Evaluating Snowmelt Runoff, Infiltration, And Erosion In A Sagebrush-Steppe Ecosystem, Eric K. Duffin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Production of low-level radioactive waste (LLRW) has created a need for safe storage facilities. These facilities must be capable of isolating radioactive waste and preventing contamination from physical or biological intrusion until the waste material is isotopically stable. At the present time, managers of the Idaho National Engineering and Environmental Laboratory (INEEL) have a substantial database characterizing rainfall events and the subsequent impact on integrity of shallow land burial sites used for storage of LLRW. Little information has been gathered describing the processes of snow accumulation/ablation and the resulting impact on storage facilities. This study examines snowmelt runoff, infiltration, and …


Sequence Stratigraphy And Paleoecology Of The Middle Cambrian Spence Shale Member Of The Langston Formation Of Northeastern Utah And Southeastern Idaho, Scott H. Wright May 1999

Sequence Stratigraphy And Paleoecology Of The Middle Cambrian Spence Shale Member Of The Langston Formation Of Northeastern Utah And Southeastern Idaho, Scott H. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Spence Shale Member contains meter-scale, shallowing-up cycles (parasequences) and record approximately 360 ky of deposition. These meter-scale cycles are nested within transgressive systems tracts (TST) and highstand systems tracts (HST) which reflect different stages of a lower-order, higher-magnitude sea-level excursion.

Fossil assemblages are located in stratigraphic positions within the Spence Shale Member that can be predicted on the basis of sequence architecture. The cycle architecture, taphonomy, and geochemistry of the Spence parasequences confirm synthetic sections and theoretical models of meter-scale cycles developed in other studies. Delineation of meter-scale cycles, based on taphonomic and sedimentologic criteria, allows high-resolution …


Prediction Of Suburban Encroachment On The Ethan Allen Firing Range And Camp Johnson, Chittenden County, Vermont, John D. Calandrelli May 1999

Prediction Of Suburban Encroachment On The Ethan Allen Firing Range And Camp Johnson, Chittenden County, Vermont, John D. Calandrelli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Suburban encroachment is a growing concern for many National Guard training installations. The Ethan Allen. Firing Range and Camp Johnson, Vermont, are either experiencing or are completely enclosed by urban encroachment. The objective of this study was to analyze the trends of suburban growth within Chittenden County, Vermont, to evaluate growth and explore future training site viability of the Ethan Allen Firing Range and Camp Johnson.

This study focused on historical data, recent real estate transactions, population projections, and county plans for growth. Using historical and contemporary data, I developed a predictive model of suburban encroachment on Camp Johnson and …


Investigation Of The Determinants Of African Savanna Vegetation Distribution: A Case Study From The Lower Omo Basin, Ethiopia, Catherine A. Schloeder May 1999

Investigation Of The Determinants Of African Savanna Vegetation Distribution: A Case Study From The Lower Omo Basin, Ethiopia, Catherine A. Schloeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ethiopian Wildlife Conservation Organization has little information on the extent and ecological determinants of plant species composition and distribution in Omo National Park. Elsewhere, the determinants of African savanna vegetation dynamics have been the focus of numerous investigations, yet our understanding of the hierarchical nature and relative importance of any relationships remains very general. As well, our ability to derive predictions about vegetation responses is limited to extreme generalizations. African savanna landscape ecotones have received even less attention than most landscapes. In this dissertation, I test hypotheses about plant species distribution-determinant relationships in Omo National Park, a park that …


Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad May 1999

Ultraviolet-B Radiation: Effects On Pollen Of 34 Taxa, And Inheritance Patterns And Carryover Of Radiation Response In Arabidopsis, Javad Torabinejad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although considerable research has addressed effects of elevated ultraviolet-B (UV-8) radiation on vegetative plant structures and processes, the reproductive biology and patterns of inheritance of UV-B tolerance have received much less attention. I examined the effects of UV-B radiation on pollen of 34 taxa. I also addressed questions concerning the patterns of inheritance of UV-B tolerance in Arabidopsis thaliana and examined potential cumulative carryover effects of UV-B exposure through multiple generations of this species.

In the first study, a significant reduction in pollen germination occurred in only five species, but pollen tube growth in more than half of the species …


Chemical And Hydrostratigraphic Characterization Of Ground Water And Surface Water Interactions In Cache Valley, Utah, J. Mike Robinson May 1999

Chemical And Hydrostratigraphic Characterization Of Ground Water And Surface Water Interactions In Cache Valley, Utah, J. Mike Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of five east-west and two north-south hydrostratigraphic cross sections were drawn from drillers' logs of water wells within the southern half of Cache Valley, Utah. These cross-sections demonstrate that ground water flow to streams is restricted by a continuous low- II permeability layer, nearly 100-feet thick. This layer was correlated to the lake-bottom deposits of the Bonneville (30,000 -13,000 years ago) and Little Valley (140,000 - 90,000 years ago) cycles of the ancient Lake Bonneville.

The most productive aquifers in the valley, collectively termed the principal aquifer , are in the southeast corner , approximately between Smithfield and …


Cenozoic Structural And Stratigraphic Evolution Of The Southeastern Salmon Basin, East-Central Idaho, James J. Blankenau May 1999

Cenozoic Structural And Stratigraphic Evolution Of The Southeastern Salmon Basin, East-Central Idaho, James J. Blankenau

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The southeastern Salmon basin (SB) of east-central Idaho is a complex east-dipping half graben containing four unconformity-bounded sequences of Tertiary volcanic, alluvial fan, lacustrine, and fluvial deposits. From oldest to youngest these are the Challis volcanic group, sedimentary rocks of Tendoy (new name), sedimentary rocks of Sacajaweja (new name), and Quaternary-Tertiary deposits . The thick sequence of volcanic rocks was deposited in a southeast-trending paleovalley . New mapping, cross-cutting relationships, 40Ar/39Ar age determinations, and angular unconformities show that the SB has experienced at least four episodes of extension, and that it lies in the core of an …


Measurement Of Angle-Resolved Secondary Electron Spectra, Robert Davies May 1999

Measurement Of Angle-Resolved Secondary Electron Spectra, Robert Davies

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Theoretical formulations of secondary electron emission over the past 20 years have exceeded the confirming ability of available measurements. An instrument has been developed and tested for the purpose of obtaining simultaneous angle- and energy-resolved (AER) secondary and backscattered electron measurements for energetic electrons incident on conducting surfaces. The instrument is found to be in good working order and the data quality found to be excellent for nearly all angles and energies investigated. A representative set of AER measurements has been acquired for 1500 eV electrons normally incident on polycrystalline gold. The data have been used to construct angle-resolved (AR) …


Tertiary Stratigraphy And Structural Geology, Wellsville Mountains To Junction Hills, North-Central Utah, Kathryn M. Goessel May 1999

Tertiary Stratigraphy And Structural Geology, Wellsville Mountains To Junction Hills, North-Central Utah, Kathryn M. Goessel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study integrates detailed mapping of Tertiary deposits along the divide between the lower Bear River basin and the Cache Valley basin with several other techniques to generate a depositional model, define extension-related structures, and compile a geologic history for this part of the northeastern Basin and Range province. The study area is situated along the topographic divide between Box Elder and Cache Counties, Utah, from the Wellsville Mountains north almost to Clarkston Mountain. These ranges are cored by folded and thrusted Paleozoic rocks. They are bound on the west by normal faults of the Wasatch fault zone and on …


Radar And Satellite Global Equatorial F-Region Vertical Drift Model, L. Scherliess, Bela G. Fejer Apr 1999

Radar And Satellite Global Equatorial F-Region Vertical Drift Model, L. Scherliess, Bela G. Fejer

Bela G. Fejer

We present the first global empirical model for the quiet time F region equatorial vertical drifts based on combined incoherent scatter radar observations at Jicamarca and Ion Drift Meter observations on board the Atmospheric Explorer E satellite. This analytical model, based on products of cubic-B splines and with nearly conservative electric fields, describes the diurnal and seasonal variations of the equatorial vertical drifts for a continuous range of all longitudes and solar flux values. Our results indicate that during solar minimum, the evening prereversal velocity enhancement exhibits only small longitudinal variations during equinox with amplitudes of about 15–20 m/s, is …


Race, Ethnicity And Use Of The National Park System, Dr. Myron Floyd, National Park Service, Department Of The Interior Apr 1999

Race, Ethnicity And Use Of The National Park System, Dr. Myron Floyd, National Park Service, Department Of The Interior

All U.S. Government Documents (Utah Regional Depository)

This paper reviews the social science literature on racial and ethnic minority use of the National Park System. Four theoretical perspectives are examined--the marginality hypothesis, subcultural hypothesis, assimilation theory, and the discrimination hypothesis. Each perspective is described, and its strengths and limitations discussed. Research on race, ethnicity, and participation in outdoor recreation is also examined. Studies consistently show that racial and ethnic groups visit national parks and participate in recreation activities at differing rates. The style and pattern of park use also vary among racial and ethnic groups. Social science research on this topic can help park managers serve the …


Pretty Tree Bench Vegetation Project, Draft Environmental Impact Statement, Usda Forest Service Apr 1999

Pretty Tree Bench Vegetation Project, Draft Environmental Impact Statement, Usda Forest Service

All U.S. Government Documents (Utah Regional Depository)

This Draft Environmental Impact Statement documents the analysis of the No Action, Proposed Action, and three action alternatives developed for the Pretty Tree Bench Project area. The Proposed Action and action alternatives considered in detail, are consistent with current management direction. Each alternative responds differently to the issues associated with the Proposed Action.

The Proposed Action prescribes disturbances within a number of different vegetation types throughout the project area. One disturbance practice uses prescribed fire. The acres of treatment by vegetation type through the use of prescribed fire are: Sagebrush (200-250 acres), Gambel Oak (450-500 acres), Pinyon/Juniper (3000-3500 acres), Ponderosa …


Classification Of Great Basin Plant Communities Occurring On Dugway Proving Ground, Utah, Vel Emrick, Alison Hill Mar 1999

Classification Of Great Basin Plant Communities Occurring On Dugway Proving Ground, Utah, Vel Emrick, Alison Hill

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.