UNT Theses and Dissertations - 18,578 Matching Results

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Effect of Surface Treatment on the Performance of CARALL, Carbon Fiber Reinforced Aluminum Joints

Description: Fiber-metal laminates (FML) are the advanced materials that are developed to improve the high performance of lightweight structures that are rapidly becoming a superior substitute for metal structures. The reasons behind their emerging usage are the mechanical properties without a compromise in weight other than the traditional metals. The bond remains a concern. This thesis reviews the effect of pre-treatments, say heat, P2 etch and laser treatments on the substrate which modifies the surface composition/roughness to impact the bond strength. The constituents that make up the FMLs in our present study are the Aluminum 2024 alloy as the substrate and the carbon fiber prepregs are the fibers. These composite samples are manufactured in a compression molding process after each pre-treatment and are then subjected to different tests to investigate its properties in tension, compression, flexural and lap shear strength. The results indicate that heat treatment adversely affects properties of the metal and the joint while laser treatments provide the best bond and joint strength.
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Date: August 2017
Creator: Bandi, Raghava
Partner: UNT Libraries

Effect of Task Appropriateness, Social Comparison, and Feedback on Female Goals, Performance, and Self-Confidence with a Motor Task

Description: Lenney (1977) concluded that achievement gender differences were predicted by females' lower self confidence and expectancies in competitive situations, identifying three variables that mediated female self confidence in achievement situations, (1) task appropriateness. (2) social comparison, and (3) feedback. The present study manipulated all three mediating variables with 240 undergraduate 18-25 year old female subjects with the pursuit rotor task that requires tracking a moving (40 rpm's) white light with a hand-held stylus for 60 seconds. Response measurement was based upon time on target. Subjects were tested over five trials while setting goals for each trial. Females were randomly assigned to a male appropriate, female appropriate, or gender neutral task condition, a competition or alone condition, and to one of four feedback conditions (no feedback, feedback about own performance only, feedback about own performance that provided the perception that subject was performing better than an opponent and/or average on each trial, or feedback about own performance that provided the perception that subject was performing poorer than an opponent and/or average on each of the five trials). Results from the 2 (social comparison) X 3 (task appropriateness) X 4 (feedback) ANOVA were contradictory to previous findings (Corbin, 1981; Petruzzello & Corbin, 1988) as females performed significantly better in competition than alone. Data support the conclusion that presentation of clear and unambiguous feedback enhanced female self-confidence (Corbin, 1981; Petruzzello & Corbin, 1988; Lenney, 1977). Data also provide null findings for the task appropriateness condition which contradicts the previous research (Corbin, 1981; Lenney, 1977) in that females perceiving the task as male appropriate did not exhibit less self-confidence and perform poorer than when the task was perceived as either female appropriate or gender neutral. Conclusions reflect methodological differences from previous research and changes in gender role identification that have significantly impacted on female ...
Date: May 1990
Creator: Adler, William P.
Partner: UNT Libraries

The Effect of Teacher Participation iIn Writing Assignments on Children's Attitudes Towards Writing and on Children's Abilities to Write

Description: The purpose of this study was to determine whether students' attitudes towards writing and their abilities to write were affected by their teacher's participation in their writing assignments. The null hypotheses that no significant differences would be found were supported. The control group and two experimental groups were all composed of fourth, fifth, and sixth graders from a racially mixed elementary school in a large metropolitan school district. The two experimental groups received identical instruction in writing skills except that the teacher wrote with one group and not with the other. The attitude scale, constructed for this experiment, proved to be statistically invalid and unreliable.
Date: August 1982
Creator: McIntosh, Margaret E.
Partner: UNT Libraries

The effect of teacher training in the use of computer graphing software on the achievement of Algebra II students

Description: The purpose of this study was to investigate the effectiveness of carefully designed teacher training in the use of the computer to teach graphing skills associated with Algebra II conic sections. Three areas were studied: the teachers' attitude toward mathematics, and the effect on students' achievement in the area of graphing skills.
Date: August 1991
Creator: Loop, Sallie Bell Jackson
Partner: UNT Libraries

The effect of teacher training on internet usage in the classroom

Description: The purpose of this study is to determine the impact on student use of electronic information systems when teachers have been given instruction on their use. By providing teachers with a solid introduction to the technology, a handy reference book, and an easy-to-use evaluation tool, it is expected that they will incorporate information found on the internet into their lessons at least twice a month. In addition, teachers will allow students to access information on their own, provided computers and Internet access are available, at least once a month.
Date: August 1996
Creator: Meyer, Gay Lyn
Partner: UNT Libraries

The Effect of Teachers' Self-Esteem on Student Achievement

Description: The purpose of this study was to examine the effect of the level of teachers' self-esteem on student achievement. This study surveys and analyzes factors of teachers' self-esteem. Its results are based on (1) a review of the literature to develop an understanding of historical perspectives and research, (2) the factors involved in the development of self-esteem, (3) the role of the parents, and (4) the role of the teacher. Forty-three teachers of grades three and five in North Central Texas completed the Gordon Personal Profile-Inventoiy to assess their levels of self-esteem. Six teachers with mid-range scores were eliminated from the study. The remaining 37 teachers were divided into high and low self-esteem categories. Students' Texas Learning Index scores on the Texas Assessment of Academic Skills were matched with the appropriate teachers' scores. The findings of the study indicate that the students with teachers in the high level of self-esteem category scored an average of 5.67 points higher than those students with teachers in the low level of self-esteem categoiy. Findings resulting from the study led to the conclusion that teachers with high levels of self-esteem have a positive influence on the achievement of their students.
Date: May 1997
Creator: Hartley, Melba Lynn
Partner: UNT Libraries

The Effect of Teaching Beginning College Mathematics by Television

Description: The purposes of this study were (1) to compare the achievement levels of students enrolled in a beginning college mathematics course when taught by (a) closed-circuit television followed by student-assisted study periods, (b) closed circuit television followed by access to videotape replay with no supervised study periods, (c) closed-circuit television followed by unsupervised study and discussion, and (d) regular lecture-recitation methods conducted by the television instructor, and (2) to ascertain the students' attitudes toward their instructor, course, and method of instruction.
Date: August 1970
Creator: Backens, Vern W. (Vern William)
Partner: UNT Libraries

Effect of Technology Integration Education on the Attitudes of Teachers and their Students

Description: This study analyzed the effect of technology integration education on teachers' and students' attitudes toward information technology. Two instruments measuring similar attributes were used to assess teachers' and students' attitudes. Differences in pre- and post-test scores were used to determine changes that occurred during the course of the study.
Date: December 1997
Creator: Christensen, Rhonda
Partner: UNT Libraries

The Effect of Test Anxiety Reduction Intervention on United States Air Force Allied Health Care Students

Description: This study examined the effects of test anxiety reduction strategies on U.S. Air Force allied health care students and had a fourfold purpose. The first was to estimate the extent of student test anxiety in allied health care students. The second was to determine the predictors of student test anxiety. The third was to determine if the Student Learning Center provides an effective method of reducing test anxiety in the subjects. The final purpose was to recommend areas for future research.
Date: December 1996
Creator: Sterling, Jimmy L. (Jimmy Lee)
Partner: UNT Libraries

The Effect of Texas Charter High Schools on Diploma Graduation and General Educational Development (Ged) Attainment

Description: This dissertation is a study of the effect of Texas's charter high schools on diploma graduation and General Educational Development (GED) attainment. Utilizing data from the Texas Schools Project at the University of Texas at Dallas, the study follows a cohort of Texas students enrolled as 10th graders in the fall of 1999 and tracks their graduation outcomes through the summer of 2002 when they were expected to have completed high school. The analysis uses case study research and probit regression techniques to estimate the effect of charter school attendance on graduation and GED outcomes as well as the effect of individual charter school characteristics on charter students' graduation outcomes. The study's results indicate that charter school attendance has a strong negative effect on diploma graduation and a strong positive effect on GED attainment. In addition, the study finds that charter schools that offer vocational training, open entry/exit enrollment options, and charters that are operated in multiple sites or "chain" charters have positive effects on charter students' diploma graduation outcomes. Charters that offer accelerated instruction demonstrate a negative effect on diploma graduation. The study finds that charter school graduation outcomes improve as charters gain experience and that racially isolated minority charter schools experience reduced graduation outcomes. The study's results also indicate that Texas's charter high schools may be providing district schools with a means through which to offload students who may be difficult to educate. The analysis finds that districts may be pushing low-performing high school students with attendance and discipline problems into charter schools in order to avoid the effort of educating them and to improve district performance on accountability measures related to standardized test scores and graduation rates. This finding suggests that that competition from charter high schools will not provide much incentive for districts to improve their ...
Date: August 2005
Creator: Maloney, Catherine
Partner: UNT Libraries

The Effect of Text Structure and Signaling Devices on Recall of Freshman Arab Students

Description: The problem of this study was to examine the effect of text structure and signaling devices on immediate and delayed recalls of freshman Arabic-speaking students after reading a text. Subjects for the study were forty-five freshman Arabic-speaking students enrolled in three freshman English courses at a state university. All subjects were male students. The subjects-were chosen on a voluntary basis. The subjects were given the Reading Comprehension Section of the TOEFL. They were then divided into groups of good, average, and poor readers according to their performance on the TOEFL. Two well—organized passages of expository text with clearly identifiable top-level structure of problem/solution and appropriate reading levels were selected for the study. Two versions of each passage were adapted — one with the signaling devices included in the passage and the other with the signaling devices deleted. Each subject read one version of each of the two passages. The immediate and delayed recalls of the subjects were scored by an unbiased scorer. The scorer was an expert teacher of English to foreign students. Hypothesis I stated that good readers would be able to utilize the writer's rhetorical mode of the text at a significantly higher level than average and poor readers. This hypothesis was supported. The results of Chi square analysis was significant at the .03 level for immediate recall, and at the .01 level for the delayed recall. Hypothesis II stated that readers of each of the three groups who followed the original rhetorical mode of the text would recall significantly more information than those who failed to do so. This hypothesis was also supported. The results of the Two-way Analysis of Variance were significant at the .01 level for both immediate and delayed recalls. Hypothesis III stated that the students of all three groups would recall significantly more ...
Date: May 1986
Creator: Qandil, Mahmoud Ahmed
Partner: UNT Libraries

The effect of the assimilation of the La Reunion colonists on the development of Dallas and Dallas County|cby Velma Irene Sandell

Description: This study examines the impact of the citizens of the La Reunion colony on the development of Dallas and Dallas County. The French, Belgian, and Swiss families that formed the utopian colony broughta blend of European culture and education to the Texas frontier in 1853. The founding of La Reunion and a record of its short existence is covered briefly in the first two chapters. The major part of the research, however, deals with the colonists who remained in Dallas County after the colony failed in 1856. Chapters three and four make use of city, county, and state records along with personal collections from the Dallas Historical Society Archives and the Dallas Public Library to examine the colonists effect on the government and business community. Chapter five explores the cultural development of the area through city and county records and personal collections.
Date: December 1986
Creator: Sandell, Velma Irene
Partner: UNT Libraries

The Effect of the Conflict Between Instructional Leadership and Building Management Roles on Job Satisfaction of the Texas Public High School Principal

Description: The problem of this study was the conflict perceived by Texas Public High School Principals involving two roles which have been described as contradictory in nature; namely as an instructional leader and as a building manager. This study was also concerned with the level of job satisfaction of the Texas Public High School Principal. 1,205 Texas Public High School Principals identified by the Texas Education Agency and University Interscholastic League were mailed a three part questionnaire survey. 700 principals (or 58.09% of the entire population) returned the completed surveys. The questionnaire "Demographic Survey for Texas Public High School Principals" consisted of eight questions. The thirty-four statement "Questionnaire for Texas High School Principals" allowed principals to provide their perceptions of the roles and responsibilities for their present position as well as an ideal position. The final questionnaire, the four question "Survey of Job Satisfaction", assessed the level of job satisfaction for each principal. Hypothesis one was analyzed with a one-way ANOVA to determine if principals differed in their perceptions of their job roles and job positions. These positions included both the present job position and a more desired or ideal job position. The differences in these positions resulted in conflict. Hypothesis two utilized a point bi-serial correlation to find a significant difference in the number of satisfied and dissatisfied principals. Research questions one through three compared the responses from the surveys by the demographic variables. Significant differences for perceptions of instructional leadership and building management, job satisfaction, and conflict respectively were reported. A summary, findings, conclusions, implications, and recommendations for further study, conclude the dissertation. Findings of the study conclude that the more assistance a principal has, the less conflict the principal seems to have between the roles of instructional leader and building manager.
Date: August 1990
Creator: Hulen, Chris Wendell
Partner: UNT Libraries

Effect of the Home Environment on Children's 10 Scores and the Influence of Family Socioeconomic Status

Description: Contributions of home environment and family socioeconomic status (SES) on the intelligence test performance of 24 exceptional children aged five through seven years were investigated. It was hypothesized that higher SES would enrich the children's environment providing a more stimulating learning experience, and would reflect a positive correlation with measures of the home environment. Additional hypotheses were that both HOME scores and SES scales would show a positive correlation with intelligence test performance. The positive association found between SES and HOME Inventory scores suggests that families with a higher SES have the ability to direct more resources toward their children. However, according to the present study, this does not affect the intelligence test performance of exceptional children.
Date: May 1994
Creator: Singer, David D.
Partner: UNT Libraries

The Effect of the Mental Hygiene of the Adult on the Mental Hygiene of the Child in This Emergency

Description: The purpose of this study is to determine the relationship which the thought patterns of parents have upon the ideas of the children in the present national and world emergency. Attention is also given to the background study of the present conflict, the attitudes that should prevail, and the stress that should be placed upon democracy.
Date: 1942
Creator: Miller, Ethel Lee
Partner: UNT Libraries

Effect of the New Criteria for Accreditation on Reaffirmation of Accreditation in the South

Description: This study was concerned with characteristics of the process of reaffirmation of accreditation in the Southern region among institutions that completed reaffirmation under the revised _Criteria for Accreditation_ and those that completed reaffirmation under the former _Standards of the College Delegate Assembly._ The institutions that had completed reaffirmation under the new _Criteria_ were identified. A matching group of equivalent institutions which had last completed reaffirmation under the _Standards_ was created. Each group contained 66 institutions. Data were collected using the records of the Commission on Colleges of the Southern Association of Colleges and Schools. Four areas were identified in which the implementation of the _Criteria_ might affect the process of reaffirmation of accreditation: (a) institutional organization for the self-study, (b) visiting committee composition, (c) number of recommendations by visiting committees, and (d) substance of recommendations by visiting committees. A series of nine hypotheses were tested to assess these effects. The process of reaffirmation of accreditation does not appear to have been substantially affected by the implementation of the new _Criteria for Accreditation._ Institutional organization for the self-study appears unaffected by the implementation of the Criteria for most institutions. There appears, however, to be evidence that the _Criteria_ have effected change for a minority of institutions. The implementation of the _Criteria for Accreditation_ does not appear to have influenced either the size or the composition of visiting committees of peers. The implementation of the _Criteria for Accreditation_ has not increased the average number of recommendations by visiting committees of peers, but there appears to be evidence that it has created a minimum core of recommendations common to many institutions. The addition of the criterion on institutional effectiveness apparently has created a new and proportionately overrepresented focus for visiting committee recommendations.
Date: May 1988
Creator: Freeman, Irving
Partner: UNT Libraries

The Effect of the Socio-Economic Status of Sixth-Grade Pupils on Arithmetic Attainment

Description: The purposeof this study is to determine the effect of the socio-economic status of the homes of sixth-grade pupils on their arithmatic attainment. It also aims to point out the effect of social and economic factors of home environment on each of the four arithmatical abilities through a critical analysis and interpretation of the data.
Date: August 1938
Creator: Webb, Mary Carlisle
Partner: UNT Libraries

The Effect of the Specific Teaching of Mathematical Concepts in Second Year Algebra

Description: The purpose of this study was to correlate the Vegetation of the Woodbine Sands with the edaphic factors. In the laboratory an analysis of the edephic factors was made of the twenty-two soil types collected from the three formations. The results of these and other analysis are shown in tables and graphs. The results indicate that the vegetational cover of an area that is uniform in its origin and in its resident soil factors is determined by the edaphic factors present.
Date: August 1936
Creator: Gross, John Milton
Partner: UNT Libraries

The Effect of the Tonic Neck Reflex upon Fatigue of the Extensor Leg Muscles

Description: The purpose of the investigation was to determine the effect of the tonic neck posture upon fatigue induced by exhaustive exercise of the knee extensor muscles of college women. The subjects were college females enrolled in physical education activity classes at North Texas State University. The F ratio was used to determine significance of the difference in fatigue measures in the three head positions. The results of the present investigation revealed no statistically significant difference between the three head positions with respect to their influence on endurance of the leg extensors. Conclusions were that the tonic neck reflex does not facilitate or inhibit leg extensor endurance.
Date: August 1974
Creator: Cate, Susan Carol
Partner: UNT Libraries