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Examining the Role of Latitude and Differential Insolation in Asymmetrical Valley Development

Description: Valley development through erosional processes typically tends to create symmetrical valleys. Over time, water cuts through the substrate to create valleys, gorges, and canyons for which the sides are the valley are evenly sloped. However, there are anomalies to this process. Asymmetrical valleys have been well-documented even in areas of uniform substrate or little tectonic uplift. One proposed explanation for the asymmetry of these valleys is differential insolation. This may lead to different microclimates from one slope to another which alter the rate and extent of erosion. Since the differences in received insolation vary with latitude (especially in streams that flow along an east/west axis), it follows that the degree of asymmetry should also vary with latitude if differential insolation is a primary driving factor in the development of these valleys. To evaluate if insolation plays a role in the development of asymmetrical valleys, this study examines variability in asymmetry across 447 valleys in nine study areas located at different latitudes. The degree of asymmetry for each valley was measured by using 30 meter resolution digital elevation models (DEMs) to determine the slope angle of each side of the valley. Asymmetry was measured by computing a ratio of the average slope angle for each side of the valley (larger value divided by smaller). If the resulting value is one, the valley is deemed symmetrical. As the value increases, the degree of asymmetry increases. This investigation found that contrary to expectations, valleys at lower latitudes tend to have a higher degree of asymmetry than those at higher latitudes, which suggests that differential insolation does not play a major role in the development of these valleys. Instead, this study found that high altitudes and low latitudes are more frequently associated with a higher degree of asymmetry. These unexpected findings open the door ...
Date: August 2013
Creator: Curran, Lorna L.

Examining the Shade/flood Tolerance Tradeoff Hypothesis in Bottomland Herbs Through Field Study and Experimentation

Description: While there is growing evidence that shade/flood tolerance tradeoffs may be important in distributions of bottomland hardwood trees and indications that they should apply to herbs, no studies have definitively explored this possibility. Four years of field data following historic flooding were supplemented with a greenhouse experiment designed to identify interactions congruent with tradeoffs. Fifteen bottomland species were grown in two levels of water availability and three levels of shade over 10 weeks. Results indicate responses of Fimbristylis vahlii and Ammannia robusta are consistent with tradeoffs. Modification of classical allometric responses to shade by substrate saturation indicates a potential mechanism for the tradeoff in A. robusta. Responses indicating potential for increased susceptibility to physical flooding disturbance are also discussed.
Date: May 2012
Creator: Sloop, Jordan

Examining Visual Art Experiences for Relationship Building in Shared-site Locations

Description: This study explored the perceptions of 74 activity directors responsible for the intergenerational programming that is currently taking place at shared-sites, facilities where older adults and young people receive services and programs simultaneously in a co-located space. Data for this study was collected through a national survey of 149 shared-sites collected from the Generations United data base. the questionnaire asked respondents about their facility’s intergenerational programming, demographic information, and perceived sense of community exhibited by participants in the intergenerational program. Descriptive data regarding the location, primary emphasis, ages and number served, and specific program characteristics, including visual art programming, at IGSS facilities were collected and analyzed. Results from the analysis were reported with limitations. There was a statistical significance suggested in the association of the frequency and duration of art activities with some of the sense of community variables. the study is valuable in determining the current demographics of IGSS facilities that offer visual art programs. Further research needs to be conducted to answer questions regarding the specific role that the visual arts play in creating a sense of community among intergenerational participants at shared-site facilities.
Date: May 2012
Creator: Whiteland, Susan

Examples and Applications of Infinite Iterated Function Systems

Description: The aim of this work is the study of infinite conformal iterated function systems. More specifically, we investigate some properties of a limit set J associated to such system, its Hausdorff and packing measure and Hausdorff dimension. We provide necessary and sufficient conditions for such systems to be bi-Lipschitz equivalent. We use the concept of scaling functions to obtain some result about 1-dimensional systems. We discuss particular examples of infinite iterated function systems derived from complex continued fraction expansions with restricted entries. Each system is obtained from an infinite number of contractions. We show that under certain conditions the limit sets of such systems possess zero Hausdorff measure and positive finite packing measure. We include an algorithm for an approximation of the Hausdorff dimension of limit sets. One numerical result is presented. In this thesis we also explore the concept of positively recurrent function. We use iterated function systems to construct a natural, wide class of such functions that have strong ergodic properties.
Date: August 2000
Creator: Hanus, Pawel Grzegorz

Exceedance Frequency Analysis of Urban Stormwater Quality and Its Relation to Land Use Change, Denton, Texas

Description: Urbanization causes various environmental issues including water pollution, air pollution, and solid waste. Urbanization of watersheds has a profound influence on the quality of stormwater runoff. The quality of stormwater runoff is highly associated with land use. This study analyzed the exceedance frequency of stormwater quality in five watersheds of Denton over eleven years and also analyzed the relationship between stormwater quality and land use/cover of each watershed. The results showed that the most of the water quality parameters that were examined in the Lower Pecan watershed exceeded their threshold most frequently. The higher frequency of exceedance in this watershed can be attributed to the wastewater treatment plant and landfill site. Total suspended solids and turbidity were frequently exceeded in Hickory and Clear Creek watersheds. Conductivity was found to have highest percentage of exceedance in Upper Pecan and Cooper watersheds. Thus, rural watersheds were related with higher exceedance of TSS and turbidity whereas urban watersheds were related with higher exceedance of conductivity.
Date: August 2015
Creator: Shrestha, Manjul

Exceptional Properties in Friction Stir Processed Beta Titanium Alloys and an Ultra High Strength Steel

Description: The penchant towards development of high performance materials for light weighting engineering systems through various thermomechanical processing routes has been soaring vigorously. Friction stir processing (FSP) - a relatively new thermomechanical processing route had shown an excellent promise towards microstructural modification in many Al and Mg alloy systems. Nevertheless, the expansion of this process to high temperature materials like titanium alloys and steels is restricted by the limited availability of tool materials. Despite it challenges, the current thesis sets a tone for the usage of FSP to tailor the mechanical properties in titanium alloys and steels. FSP was carried out on three near beta titanium alloys, namely Ti6246, Ti185 and Tiβc with increasing β stability index, using various tool rotation rates and at a constant tool traverse speed. Microstructure and mechanical property relationship was studied using experimental techniques such as SEM, TEM, mini tensile testing and synchrotron x-ray diffraction. Two step aging on Ti6246 had resulted in an UTS of 2.2GPa and a specific strength around 500 MPa m3/mg, which is about 40% greater than any commercially available metallic material. Similarly, FSP on an ultra-high strength steel―Eglin steel had resulted in a strength greater than 2GPa with a ductility close to 10% at around 4mm from the top surface of stir zone (SZ). Experimental techniques such as microhardness, mini-tensile testing and SEM were used to correlate the microstructure and properties observed inside SZ and HAZ's of the processed region. A 3D temperature modeling was used to predict the peak temperature and cooling rates during FSP. The exceptional strength ductility combinations inside the SZ is believed to be because of mixed microstructure comprised of various volume fractions of phases such as martensite, bainite and retained austenite.
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Date: May 2017
Creator: Tungala, Vedavyas

Excerpts From the Eva Crane Field Diary: Stories

Description: Male or female, young or old, the characters of this collection inhabit a liminal space of trauma and social dislocation in which elements of the real and fabulous coexist in equal measure. The ghosts that populate the stories are as much the ghosts of the living, as they are the ghosts of the dead. They represent individual conscience and an inescapable connection to the past.
Date: May 2010
Creator: Jacobs, Emily

Excuses for the Universe

Description: We create fictions--personal and literary--to cope with fear, and it is our choice whether or not these inventions affirm life. This collection presents many ways of "making excuses for the universe," both from a personal standpoint and also by using the voices and visions of created characters. The collection contains a section of family poems and three sets of character poems: Beverly and Nanci, Strange Mary, and Blue Donna. Following each section are two related poems for transition or amplification. The poems show a progressive change in writing techniques, especially experimentation with sound, as well as pursuing the central theme that perception is a desirable goal, well worth the price.
Date: August 1985
Creator: Keefe, Martha L. (Martha Lundin)

Execution Time Analysis through Software Monitors

Description: The analysis of an executing program and the isolation of critical code has been a problem since the first program was written. This thesis examines the process of program analysis through the use of a software monitoring system. Since there is a trend toward structured languages a subset of PL/I was developed t~o exhibit source statement monitoring and costing techniques. By filtering a PL/W program through a preorocessor which determines the cost of source statements and inserts monitoring code, a post-execution analysis of the program can be obtained. This analysis displays an estimated time cost for each source statements the number of times the statement w3s executed, and the product of these values. Additionally, a bar graph is printed in order to quickly locate very active code.
Date: December 1977
Creator: Whistler, Wayne C.

Executive Compensation Practices of Twenty-Five Texas Companies

Description: The specific purpose of this study will be: (1) to find what factors determine the amount of pay that executives in twenty-five Texas companies receive, and how personal factors are ranked in setting their salaries; (2) to determine present and proposed utilization of formal job evaluation methods among the twenty-five Texas companies in setting executive salaries; (3) to find which methods of remuneration are used for executives of different levels in the twenty-five Texas companies; (4) to determine who has the final responsibility for the administration of executive salaries in the twenty-five Texas companies; and (5) to determine the means used in appraising executive merit or worth in determining salary adjustments while an individual remains in the same position.
Date: August 1955
Creator: Demetruk, Jack Fredric

Executive Control of Craving: An Examination of College Students

Description: Previous research has shown that alcohol abuse may cause a deficit in frontal lobe functioning, specifically, areas of the frontal lobe that are related to executive function. Additionally, problems with executive function have been related to increased difficulty in managing cravings to addictive substances. The current study explored the relationship between alcohol use and performance on measures of executive functioning in a sample of 121 traditional college students. Students were given 5 measures of executive function designed to explore mental set shifting, updating, inhibition, sustained attention, and planning. These measures were used to examine the relationship between executive function and craving as measured by the Obsessive Compulsive Drinking Scale. Levels of alcohol use were also examined using the Alcohol Use Disorders Identification Test in relation to executive function performance and family history of alcohol abuse.
Date: May 2011
Creator: Yates, Robert Dean, III

Executive Information Seeking and the Corporate Library

Description: This study began with an interest in corporate libraries and a genuine curiosity in the information preferences and resources valued by executive leaders at JET Aircraft Co. Executive information preferences and the downward trend in special libraries initiated the investigation of information seeking among executive leaders and yielded the inquiry: What resources do JET Aircraft Co. executives value when they need information? Employing an ethnographic approach, this study investigated what JET Aircraft Co. executives know about information resources, what they believe about information resources, and how they act when they require information. While JET Aircraft Co. maintained a special corporate library called the Company Research Library (CRL), the purpose of this study was to determine what resources were of value to executives at JET Aircraft Co., understanding that the CRL may or may not be a resource executives’ value. As a byproduct, this study also sought to establish executive information preferences and perceptions of the CRL. Information seeking at the executive level, studied through an ethnographic lens, provided insight into how executives at JET Aircraft Co. work and what they prefer, and it established a baseline for the Company Research Library’s position among the resources valued by executives.
Date: May 2015
Creator: Washburn, Adrianne J.

Executive Order 2010-06 : Governor's Policy on Climate Change

Description: WHEREAS, Arizona was a founding member of the Western Climate Initiative (WCI) in February 2007; WHEREAS, the United States Environmental Protection Agency (USEPA) finalized regulations mandating GHG reporting, effective on December 29, 2009,...WHEREAS, it is critical that Arizona stay informed of and influence any federal regulation and legislation relating to climate change and capping of GHG emission...NOW, THEREFORE, I, Janice K. Brewer, Governor of the State of Arizona,...hereby order and direct as follows: 4. The Climate Change Oversight Group ("Group") is established and charged with monitoring the continued work of the WCI...11. The Group and this Executive Order shall expire December 31, 2012
Date: October 2010
Creator: Brewer, Janice K.

Executive Order - Stewardship of the Ocean, Our Coasts, and the Great Lakes

Description: This order establishes a national policy to ensure the protection, maintenance, and restoration of the health of ocean, coastal, and Great Lakes ecosystems and resources, enhance the sustainability of ocean and coastal economies, preserve maritime heritage, support sustainable uses and access, provide for adaptive management to enhance understanding of and capacity to respond to climate change and ocean acidification, and coordinate with national security and foreign policy interests. This order also provides for the development of coastal and marine spatial plans that build upon and improve existing Federal, State, tribal, local, and regional decision making and planning processes.
Date: July 19, 2010
Creator: United States. President (2009- : Obama)

Executive Participation in Innovation as a Function of Age and Tenure

Description: This study is designed to investigate the relationship between the age and tenure of the chief executive officer of a corporation and his participation in innovation. The chief executive is assumed to be the key participant in the innovation process. Two questions form the basis of the study, Firsts, are younger chief executives more innovative than older executives? And second, does the tenure of chief executives affect performance in innovation?
Date: August 1973
Creator: Donnelly, Clifford V.

Exercise Capacity Following Four Hours of Head-Down Rest in Endurance-Exercise-Trained and Untrained Subjects

Description: Peak oxygen uptake (VO2PEAK) in endurance exercise trained (ET =8) subjects (VO2PEAK = 61.7 1.6 ml 02.kg.min-1) was compared to the V02 PEAK of untrained (UT = 8) subjects (V02 PEAK = 38.4 1.7 ml 02 -kg.min1) after four hours of -6* head-down rest (HDR).Although both groups showed a reduction in blood volume (BV) following HDR, this decrement was greater for ET subjects (delta BV = -3.23 0.46 mi/kg; P <0.05). The ET subjects had a greater decrease in VO2=(delta 02E -5.58 1.05 ml 02-kg.min-1; P <0.05) than their UT peers (VO2PEAK = -2.44 0.79 ml02-kg.min-1). These data suggest that the greater reductions in VO2PE, observed for the ET group were associated with a greater BV loss resulting from 4 h of HDR prior to exercise.
Date: December 1990
Creator: Williamson, Jon W.

An exercise in story repair: A guided written disclosure protocol for fostering narrative completeness of traumatic memories.

Description: Flutists have reported musculoskeletal pain from practicing and performing their instrument. This study was a statistical approach to investigate potential causal risk factors for flute related pain among high school and college students. The study focused on the relationship between flute related pain and musical background or anthropometric measurements including size, strength and flexibility. Subjects included thirty high school and college-aged flutists who were assessed using a questionnaire, bi-lateral anthropometric measurements of the upper-extremities, upper-extremity performance tests for range of motion, isometric strength and rotation speed, and instrument specific questions. Four questions regarding pain associated with flute playing were treated as dependent variables and used for correlation and regression analyses with other independent variables. A six-factor regression model was created and each model was statistically significant. Results of this study show that strength, flexibility, pain spots, and exposure are risk factors for flute related pain. Both left and right pinch strength and right isometric pronation strength were significantly correlated to flutists experiencing pain while playing. Knowledge of these factors in relationship to pain is needed in flute pedagogy to help teachers and performers understand why flutists report pain during and after playing. Additional studies are warranted for replication of this study and for determining the clinical and pedagogical relevance of these findings.
Date: May 2008
Creator: Tomczyk, Daniel A.

Exercises for Preparing Singers to Perform Contemporary Choral Music

Description: This treatise has been prepared largely because of an increasing interest in contemporary music and an awareness on the part of many music educators of its merits in the curriculum of public schools and colleges. Since contemporary music is a controversial subject among directors, it has become necessary to search for specific, positive approaches to the teaching of contemporary music in high school.
Date: August 1967
Creator: Ivey, Milvern K.

Exhaustivity, continuity, and strong additivity in topological Riesz spaces.

Description: In this paper, exhaustivity, continuity, and strong additivity are studied in the setting of topological Riesz spaces. Of particular interest is the link between strong additivity and exhaustive elements of Dedekind s-complete Banach lattices. There is a strong connection between the Diestel-Faires Theorem and the Meyer-Nieberg Lemma in this setting. Also, embedding properties of Banach lattices are linked to the notion of strong additivity. The Meyer-Nieberg Lemma is extended to the setting of topological Riesz spaces and uniform absolute continuity and uniformly exhaustive elements are studied in this setting. Counterexamples are provided to show that the Vitali-Hahn-Saks Theorem and the Brooks-Jewett Theorem cannot be extended to submeasures or to the setting of Banach lattices.
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Date: May 2004
Creator: Muller, Kimberly O.

Exhibit Eh: Canadian Dependency, U.S. Hegemony, and the Amorphousness of English Canadian Culture

Description: This thesis begins by examining the factors that have resulted in the dependent nature of Canada's political and economic structure, and proceeds to examine how this has contributed to the cultural amorphousness of English Canadian identity. The hegemonic authority of American and trans-national interests, established and maintained in the cultural sphere through the extensive monopoly of the distribution of cultural and media products, perpetuates the amorphousness of English Canadian culture through the appropriation of Canadian space by the international image industry. Such categorization of Canadian space reflects and perpetuates the imaginary representation of Canada within the dominant ideology as an indistinct and amorphous entity, and comes to usurp the materiality that constructs the lived identities of English Canadians.
Date: August 1999
Creator: McIntosh, Andrew

The Exhibition as a Medium for Developing Community Awareness to Good Design in Useful Objects Available in Wichita Falls, Texas

Description: Realizing the need on the part of the general public for a better background for selection of useful household objects that combine utility and beauty of line, the author planned an exhibition in an attempt to develop a community awareness to good design in useful objects available in Wichita Falls, Texas.
Date: June 1951
Creator: Tyson, Phoebe W.