Field Validation of Zero Energy Lab Water-to-Water Ground Coupled Heat Pump Model (open access)

Field Validation of Zero Energy Lab Water-to-Water Ground Coupled Heat Pump Model

Heat pumps are a vital part of each building for their role in keeping the space conditioned for the occupant. This study focuses on developing a model for the ground-source heat pump at the Zero Energy lab at the University of North Texas, and finding the minimum data required for generating the model. The literature includes many models with different approaches to determine the performance of the heat pump. Each method has its pros and cons. In this research the equation-fit method was used to generate a model based on the data collected from the field. Two experiments were conducted for the cooling mode: the first one at the beginning of the season and the second one at the peak of the season to cover all the operation conditions. The same procedure was followed for the heating mode. The models generated based on the collected data were validated against the experiment data. The error of the models was within ±10%. The study showed that the error could be reduced by 20% to 42% when using the field data to generate the model instead of the manufacturer’s catalog data. Also it was found that the minimum period to generate the cooling …
Date: May 2016
Creator: Abdulameer, Saif
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Ozone Pollution of Shale Gas Activities in North Texas (open access)

Ozone Pollution of Shale Gas Activities in North Texas

The effect of shale gas activities on ground-level ozone pollution in the Dallas-Fort Worth area is studied in detail here. Ozone is a highly reactive species with harmful effects on human and environment. Shale gas development, or fracking, involves activities such as hydraulic fracturing, drilling, fluid mixing, and trucks idling that are sources of nitrogen oxides (NOX) and volatile organic compounds (VOC), two of the most important precursors of ozone. In this study two independent approaches have been applied in evaluating the influences on ozone concentrations. In the first approach, the influence of meteorology were removed from ozone time series through the application of Kolmogorov-Zurbenko low-pass filter, logarithmic transformation, and subsequent multi-linear regression. Ozone measurement data were acquired from Texas Commission on Environmental Quality (TCEQ) monitoring stations for 14 years. The comparison between ozone trends in non-shale gas region and shale gas region shows increasing ozone trends at the monitoring stations in close proximity to the Barnett Shale activities. In the second approach, the CAMx photochemical model was used to assess the sensitivity of ozone to the NOX and VOC sources associated with shale oil and gas activities. Brute force method was applied on Barnett Shale and Haynesville Shale emission …
Date: May 2016
Creator: Ahmadi, Mahdi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
"Miss Kathy" (open access)

"Miss Kathy"

Miss Kathy is a documentary film that tells the story of Kathy Griffin-Grinan, a lead recovery coach for prostitution and human trafficking with the Harris County Sheriff’s Office. Her non-profit organization —We’ve Been There, Done That – works in conjunction with law-enforcement to offer the survivors of prostitution a chance at rehabilitation. With endless enthusiasm, she mentors survivors as they struggle to escape a destructive lifestyle. This film also explores the relationship between human trafficking and prostitution, while addressing issues of victimization and exploitation.
Date: May 2015
Creator: Alexander, Jeffrey, 1982-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Nuestra Voz De North Texas (Fort Worth, Tex.), Vol. 1, No. 7, Ed. 1, May/June 2014 (open access)

Nuestra Voz De North Texas (Fort Worth, Tex.), Vol. 1, No. 7, Ed. 1, May/June 2014

Newspaper providing news and information to the Tarrant and Dallas County Latino communities along with advertising.
Date: May 2014
Creator: Alvarado, Felix
Object Type: Newspaper
System: The Portal to Texas History
Nuestra Voz De North Texas (Fort Worth, Tex.), Vol. 2, No. 18, Ed. 1, May 2015 (open access)

Nuestra Voz De North Texas (Fort Worth, Tex.), Vol. 2, No. 18, Ed. 1, May 2015

Monthly newspaper providing news and information to the Tarrant, Dallas, and Denton County Latino communities along with advertising.
Date: May 2015
Creator: Alvarado, Felix
Object Type: Newspaper
System: The Portal to Texas History
Nuestra Voz (Fort Worth, Tex.), Vol. 2, No. 24, Ed. 1, May 2016 (open access)

Nuestra Voz (Fort Worth, Tex.), Vol. 2, No. 24, Ed. 1, May 2016

Monthly newspaper providing news and information to the Tarrant, Dallas, and Denton County Latino communities along with advertising.
Date: May 2016
Creator: Alvarado, Felix
Object Type: Newspaper
System: The Portal to Texas History
Nuestra Voz (Fort Worth, Tex.), Vol. 3, No. 42, Ed. 1, May 2017 (open access)

Nuestra Voz (Fort Worth, Tex.), Vol. 3, No. 42, Ed. 1, May 2017

Monthly newspaper providing news and information to the Tarrant, Dallas, and Denton County Latino communities along with advertising.
Date: May 2017
Creator: Alvarado, Felix
Object Type: Newspaper
System: The Portal to Texas History
Southwest Retort, Volume 62, Number 9, May 2010 (open access)

Southwest Retort, Volume 62, Number 9, May 2010

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2010
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 63, Number 9, May 2012 (open access)

Southwest Retort, Volume 63, Number 9, May 2012

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2011
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 64, Number 8, May 2012 (open access)

Southwest Retort, Volume 64, Number 8, May 2012

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2012
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 65, Number 9, May 2013 (open access)

Southwest Retort, Volume 65, Number 9, May 2013

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2013
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 66, Number 9, May 2014 (open access)

Southwest Retort, Volume 66, Number 9, May 2014

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2014
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 67, Number 9, May 2015 (open access)

Southwest Retort, Volume 67, Number 9, May 2015

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2015
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 68, Number 9, May 2016 (open access)

Southwest Retort, Volume 68, Number 9, May 2016

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2016
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 69, Number 9, May 2017 (open access)

Southwest Retort, Volume 69, Number 9, May 2017

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2017
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 70, Number 9, May 2018 (open access)

Southwest Retort, Volume 70, Number 9, May 2018

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2018
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Southwest Retort, Volume 71, Number 9, May 2019 (open access)

Southwest Retort, Volume 71, Number 9, May 2019

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: May 2019
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
A Comparative Analysis of State Funds on Student Achievement of Economically Disadvantaged Elementary Schools in Independent School Districts and Charter Schools in the State of Texas (open access)

A Comparative Analysis of State Funds on Student Achievement of Economically Disadvantaged Elementary Schools in Independent School Districts and Charter Schools in the State of Texas

The purpose of this study was to evaluate the relationship between the instructional outcomes in the independent school districts and charter schools in relation to the expenditure of public funds for instruction and total operating expenditures from the general fund. The study considered Texas elementary charter schools and independent school districts, whose school populations were identified as having greater than or equal to 50% of economically disadvantaged students, according to the Texas Academic Excellence Indicator System (AEIS). The study made use of multiple regression and was an ex post facto cross-sectional analysis utilizing production function theory. The study’s outcomes reported the difference in student achievement between elementary schools in independent public school districts and charter schools were small to negligible for math and reading achievement. The study also reported, there is no statistically significant difference in per pupil expenditure of public funds between elementary schools in independent public school districts and charter schools. Furthermore, there is no statistically significant relationship between student achievement and per pupil expenditure of public funds on elementary schools in independent public school districts and charter schools.
Date: May 2015
Creator: Applewhite, Gary
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Determinants of Principal Pay in the State of Texas (open access)

Determinants of Principal Pay in the State of Texas

The purpose of the study was to examine district, campus, and community determinants of principal’s salaries using a spatial econometric framework. Among the district variables business tax (p = 0.001), property tax (p < .01), and the Herfindahl Index (measure of competition) were statistically significant indicators of principal salaries. The results suggest that more affluent districts tend to pay principals higher salaries, which was expected. Regarding campus characteristics, the percent of economically disadvantaged was not a statistically sound indicator (p = 0.468), but campus enrollment was significant (p = <.01). Interestingly as the percentage of economically disadvantaged students increased, the principal salary decreased. In contrast, as student enrollment increases the salary of principals increases, suggesting that principals of larger campuses earn higher salaries. Interestingly, student achievement was not a statistically significant predictor of principals’ salary given that pay for performance in Texas is at the forefront of political debate. Among the variables examined at the community level, only the percentage of homes owner occupied (p = 0.002) was found to be a statistically significant indicator of principal salary (p = .002). The lack of evidence on reforms, such as determinants of principal salary, points to data and research deficiencies to …
Date: May 2016
Creator: Asbury, Elizabeth Ann
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Levanten La Mano Si Me Entienden: Receptive Bilinguals’ Linguistic and Cultural Perceptions in Secondary Spanish Classes (open access)

Levanten La Mano Si Me Entienden: Receptive Bilinguals’ Linguistic and Cultural Perceptions in Secondary Spanish Classes

Receptive bilinguals have been in a dilemma of knowing just enough Spanish to write and aurally comprehend the curriculum at the beginning-intermediate levels of a Spanish language course. This dichotomy in classrooms with mixed-ability learners has created a need to reconsider placement and pedagogical structures tailored for these students in foreign language courses. Thus, this descriptive study examined the perceptions of receptive bilinguals, drawn from two secondary Spanish courses regarding receptive bilinguals’ language use, personal Spanish language abilities and confidence, personal beliefs about the language, and contentment with the course. For this study, 31 participants were selected from two public high schools in a suburb of a large metropolitan area in north Texas. Two surveys, a listening assessment and an online questionnaire, were administered at the end of the academic year. The Likert questionnaire items were analyzed using SPSS software, while open-ended questions were coded for recurrent themes. Analyses revealed four major findings. First, with regard to influence on language use, participants’ grandparents created the most interaction with the Spanish language when compared with the other family groups. In addition, Spanish influence through television, literature, radio, and music contributed to students’ early childhood Spanish learning. Second, as to language preference, …
Date: May 2015
Creator: Baker, Adelita Gonzales
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Impact of Teacher and Student Ethnicity on Student Assessments (open access)

Impact of Teacher and Student Ethnicity on Student Assessments

The purpose of the study was to answer the questions: Do students show greater academic success in English language arts/reading as measured by the Texas Assessment of Knowledge and Skills (TAKS) exam scores in secondary education when their teachers are the same ethinicity? Do students show greater academic success in math as measured by the TAKS exam scores in secondary education when their teachers are the same ethnicity? Minority students' success on the TAKS test was compared to the assessment scores of White students from the 2010-2011, 2011-2012, and 2012-13 school year in thre suburban school districts. This topic has been a subject of discussion since the late 10970s when Cardenas and Cardenas (1977) studied the achievement among minority students and their White peers. The conversation continued through authors such as Takei and Shouse (2008), Hays (2011), Ladson-Billings (2006), Dee (2003, 2005), and Brown (2006). To answer these research questions, a hierarchical multiple regression analysis was conducted on the data collected. Although the study verified the achievement gap between minority students and White students, the study indicated no consistent pattern corroborating that minority students were more successful when taught by teachers of the same ethnicity. In many cases, students learned …
Date: May 2016
Creator: Barnes, Barbara (Principal)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Influence of Urban Green Spaces on Declining Bumble Bees (Hymenoptera: Apidae) (open access)

The Influence of Urban Green Spaces on Declining Bumble Bees (Hymenoptera: Apidae)

Bumble bees (Bombus spp.) are adept pollinators of countless cultivated and wild flowering plants, but many species have experienced declines in recent decades. Though urban sprawl has been implicated as a driving force of such losses, urban green spaces hold the potential to serve as habitat islands for bumble bees. As human populations continue to grow and metropolitan areas become larger, the survival of many bumble bee species will hinge on the identification and implementation of appropriate conservation measures at regional and finer scales. North Texas is home to some the fastest-growing urban areas in the country, including Denton County, as well as at least two declining bumble bee species (B. pensylvanicus and B. fraternus). Using a combination of field , molevular DNA and GIS methods I evaluated the persistence of historic bumble bee species in Denton County, and investigated the genetic structure and connectivity of the populations in these spaces. Field sampling resulted in the discovery of both B. pensylvanicus and B. fraternus in Denton County's urban green spaces. While the relative abundance of B. fraternus in these spaces was significantly lower than historic levels gleaned from museum recors, that of B. pensylvanicus was significantly higher. Statistical analyses found …
Date: May 2016
Creator: Beckham, Jessica L.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Identification and Participation of Latino Students in Advanced Mathematics Courses (open access)

The Identification and Participation of Latino Students in Advanced Mathematics Courses

Using a phenomenological approach, this qualitative study examined the perspectives of Latino parents and their involvement in the decision of their child to enroll in an advanced mathematics course in sixth grade. Since enrollment in Algebra I in high school is said to be a strong predictor of college attainment and with the growing number of Latino students across the nation, this study has the potential to help district and campus leaders establish whole-school systems for communicating with Latino parents to encourage their children to enroll in advanced mathematics courses at earlier grades. Participants in this study included four sixth-grade students enrolled in an advanced mathematics course, four enrolled in regular mathematics, their mother or father, two mathematics teachers, a school counselor, and two district administrators. Data analyzed included audio recordings of semi-structured interviews of each of the participants. The findings suggested that the district has proactively developed a systematic process of creating that includes six data points to create a student profile of students that will do well in advanced mathematics. This process is helping the district close the gap between total Latino school enrollment and the enrollment of Latino students in advanced mathematics. The findings also suggested that …
Date: May 2018
Creator: Blanchard, Myrna Elizabeth
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Spatial Econometric Study Examining the Determinants of Principal Salaries (open access)

A Spatial Econometric Study Examining the Determinants of Principal Salaries

The lack of evidence on reforms, such as determinants of principal salary, points to data and research deficiencies to be addressed in order to learn more about their effects and make sound public policies. The purpose of the study was to examine district and community determinants of principals’ salaries using a spatial econometric framework. The findings have implications for education policy development related to pay for contribution, rather than pay based on tenure, experience, or district wealth. The quantitative study used a spatial regression approach to model school, district, and community factors as determinants of Texas high school principal’s salary. Principal salaries are viewed from several lenses in this study by considering effective outcomes of pay defined by actual salaries and market considerations for pay as defined by community, organizational and human capital variables. Literature from the private sector as well as from the public school setting was used as a theoretical underpinning for the hypotheses set forth in this study. The findings provide empirical insights regarding how principal salaries are determined. The study found a statistically significant spatial autocorrelation relationship at p<.05 confirming geographic locations is a robust influence on principal salaries. After controlling for the spatial autocorrelation the …
Date: May 2016
Creator: Bland, J. Edward
Object Type: Thesis or Dissertation
System: The UNT Digital Library