Search Results

Marital and Social Changes in the Lives of Women who Complete the Ph.D. Degree at Midlife

Description: The percentage of women who receive doctorates has increased by over 300 percent during the past three decades. The consequences of pursuing the Ph.D. degree have always been far reaching and profound, serving as an impetus and springboard for the reconfiguration of one's beliefs, values, and professional life. The purposes of this national study were to ascertain and describe marital and social changes that occurred in the lives of women who were awarded the Ph.D. degree at midlife. A questionnaire was distributed to a sample of three-hundred women who hold the Ph.D. degree and were employed in institutions of higher education in the United States. The study sought to identify the effects of the Ph.D. experience upon the marital relationships, friendships, and social activities of women who completed the degree between the ages of thirty-five and forty-five. Demographic data were collected which were related to their marital status before, during, and after the Ph.D. experience. Both closed and open-ended questions were posed which solicited information pertaining to their post Ph.D. experience. This research reports both quantitative and qualitative findings. The majority of women who complete the Ph.D. experience at midlife undergo and initiate changes in their lives which impact their relationships and activities. Many of these changes are the result of employment which follows the award rather than the degree itself. While some women experience negative effects in some areas of their lives, overall, the findings of this study suggest that changes are perceived positively by the majority of women who receive the Ph.D. at midlife.
Date: August 1995
Creator: Sikes, Debra
Partner: UNT Libraries

Retention and Attrition of Doctoral Candidates in Higher Education

Description: A number of studies have been conducted on the attrition rates of undergraduate and graduate students. However, the body of knowledge concerning attrition for doctoral students, especially those who have attained the level of “all but dissertation” (ABD), is limited. The purpose of this research was to examine retention and attrition factors of doctoral candidates from a typical Higher Education Doctoral Program (Research II Public Institution) who were admitted to candidacy from 1991 through July 2000. Participation of the subject population was limited to those who had attained the level of ABD--those who had previously fulfilled the residency, coursework, foreign language or tool-subject requirements, and successfully completed the comprehensive/qualifying exams. This population included current ABDs, previously attrited ABDs, and graduates of the degree program. The research study was qualitative and intended to identify the effect of specific, predetermined factors that may have influenced or affected the progress of current, previous, and graduated students towards the doctoral degree in higher education. This study obtained responses to questions from the questionnaire/survey instrument concerning factors that affected program completion or attrition. Students had the opportunity to elaborate on factors from their dissertation, advisement, and personal, financial, and employment experiences that affected their ability to complete the program through open-ended question responses. By examining key factors in the doctoral degree experience from the three sample groups (current ABDs, previous ABDs, and graduated Ed.Ds), this study was able to draw some conclusions about doctoral attrition. Reconstructing and comparing the experiences of ABDs from the point of candidacy to the point of attrition or completion of the program determined trends, commonalities, and issues affecting achievement. Results of this study add to the limited research concerning ABD attrition and provide an insight from the student perspective as to the obstacles and support variables in the quest for ...
Date: December 2000
Creator: Malmberg, Eric D.
Partner: UNT Libraries

What makes a quality Ph.D. program in library and information sciences?

Description: The intent of this study was to establish and validate criteria for use to assess the quality of a library and information sciences (LIS) Ph.D. program. The Ph.D. student-centric topology for quality Ph.D. programs was developed from a 2001 position statement by the American Association of Colleges of Nursing (AACN) regarding the quality indicators in research-focused doctoral programs in nursing. Topology components were tested using a survey instrument to establish their importance to the community of practice and their potential use to assess a Ph.D. program. Survey participants were asked to rank terms or concepts in a balanced incomplete block (BIB) design then rate, on a Likert-type scale, statements about the applicability of these terms or concepts to assessing a quality LIS Ph.D. program. Survey participants were from the Association for Library and Information Science Education (ALISE) Open Lib/Info Sci Education Forum jESSE Listserv. Of 225 survey participants affiliated with universities or schools from North America who submitted usable surveys, slightly less than two-thirds (64.4 %) were female while 35.5 % were male. Ninety-eight participants (43.6 %) were faculty, 114 (50.7 %) were Ph.D. students or candidates, and 13 (5.8 %) were in other roles. Statistical analysis of survey responses showed consistent results between the different demographic groups. The topology was validated by the results of the statistical analysis of the research data. Every component of the topology was acknowledged as very important to assess the quality of a LIS Ph.D. program. Faculty was the highest ranked item in the BIB analysis with a statistically significant difference (p < .0001) in the mean rank order from the next highest ranked item, Ph.D. students. The rank order from the BIB analysis was as follows: faculty, Ph.D. students, programs (courses) of study, teaching, learning environment, resources, and evaluation. Faculty was also the ...
Date: December 2006
Creator: Klingler, Scott Lavell
Partner: UNT Libraries

The Doctoral Program in Higher Education at North Texas State University: An Appraisal

Description: Doctoral graduates of the program in Higher Education, Division of Higher Education, North Texas State University, from the fall of 1969 through spring, 1973, were selected as subjects for an evaluation of the program. To appraise the effectiveness of the program, the evaluation attempted to: (1) determine how the graduates viewed various aspects of their doctoral program and experiences at North Texas State University; (2) appraise the effectiveness of the doctoral program in Higher Education in light of the career goals and needs of the graduates and how the program served those needs; (3) present conclusions and recommendations based on the findings of the study which could aid in the administration of the program, provide information for planning new programs and policies, or in supporting those already in existence. A questionnaire was developed and used as the data-gathering instrument, after being revised according to suggestions given by a jury. The questionnaire was mailed to graduates on August 17, 1973, and a follow-up letter was mailed on September 19, 1973, to those non-respondents who could be identified. Of the total number of graduates who received the questionnaire, 69 (71 per cent) responded. Data contained in the questionnaires were numerically coded and recorded on keypunch worksheets. With the aid of the staff from the N.T.S.U. Computing Center, print-outs were produced from the worksheets which contained tabulated data. Tables were made from the data for analysis and interpretation. Analysis of the data led to the following conclusions. The program is producing graduates who have a marketable education with most of them teaching in four-year colleges and universities. The emphases on college teaching and administration are major strengths of the program and graduates rate a strong degree of satisfaction with the major program components, structure and curriculum. Competencies gained in educational research and statistics ...
Date: August 1974
Creator: Brice, Bert Charles
Partner: UNT Libraries

Two-Phase Air-Water Flow Phenomena

Description: Report issued by the Argonne National Laboratory discussing two-phase flow studies that were conducted "to obtain empirical density relationships and pressure drop friction factors for two-phase mixtures" (p. 11). This report includes tables, illustrations, and photographs.
Date: March 1958
Creator: Petrick, Michael
Item Type: Report
Partner: UNT Libraries Government Documents Department

Separation of Azeotropes by Means of Diffusion through Porous Membranes

Description: Thesis discussing experiments to separate azeotropes into pure components testing eleven minimum boiling point azeotropic systems: (1) acetone-methanol, (2) carbon tetrachloride-ethyl acetate, (3) cyclohexane-ethanol, (4) benzene-isopropanol, (5) benzene-n-propanol, (6) benzene-cyclohexane, (7) benzene-methanol, (8) benzene-ethanol, (9) acetone-carbon, (10) isopropoanol-water, and (11) ethanol-water.
Date: October 1953
Creator: Hagerbaumer, Donald H.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Propagation of Density Disturbances in Air-Water Flow

Description: From Introduction: "In this work, a forced-circulation air-water loop was employed for investigating the behavior of void perturbations. Upon attaining steady-state conditions, disturbances in the void fraction were superimposed at very low frequencies (~0.4 cps). A better understanding of hydrodynamic transient behavior will generate more confidence in the design of boiling-water reactor systems."
Date: June 1965
Creator: Nassos, George P.
Item Type: Report
Partner: UNT Libraries Government Documents Department

The Technology of Slate

Description: From Introduction: "The purpose of this bulletin is to point out the most efficient methods and equipment now in use in slate quarries, to describe methods of utilizing the quarried material to best advantage, and to outline means of reducing the proportion of waste, which is now excessive."
Date: 1922
Creator: Bowles, Oliver
Item Type: Report
Partner: UNT Libraries Government Documents Department

Two-Phase Heat Transfer With Gas Injection Through A Porous Boundary Surface

Description: From Introduction: "The purpose of this study is to investigate some of the hydrodyamic aspects of two-phase heat transfer in the lower quality range. The results of this study should contribute to a better and more thorough understanding of the processes and mechanisms affecting two-phase heat transfer, and in this way help in improving its prediction."
Date: March 1964
Creator: Kudirka, A. A.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Condensation of Metal Vapors: Mercury and the Kinetic Theory of Condensation

Description: Report issued by the Argonne National Laboratory discussing condensation theories of metal vapors. As stated in the introduction, "the objectives of this research then are critical analysis of condensation theories and data for metal vapors and experimental evaluation of the resistance to condensation for a representative metal such as mercury" (p. 18). This report includes tables, illustrations, and photographs.
Date: October 1964
Creator: Wilhelm, Donald J.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Dynamic Analysis of Coolant Circulation in Boiling Water Nuclear Reactors

Description: Report concerning the study of the two-phase flow through the cooling channels of a natural-circulation boiling water nuclear reactor. "One-dimensional conservation equations describing the flow through each channel are written in the linearized perturbed form, and Laplace transformation in time is performed." (p. 5)
Date: April 1964
Creator: Sanathanan, Chathilingath K.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Comparative Study of Perceived Barriers to Faculty Participation in Distance Education at a Four-Year University

Description: Bailey, Elizabeth, Comparative study of perceived barriers to faculty participation in distance education at a four-year university. Doctor of Philosophy (Education), December 2015, 103 pp., 21 tables, references. The purpose of this Bailey study was to identify perceived barriers of faculty participation in distance education courses in a four-year university and identify the differences in perceived barriers between the Hebert 2003 study and this Bailey study. The literature review covers numerous studies and articles written within the last 10 years that are related to a variety of barriers perceived by faculty and administrators. There were no statistically significant relationships found between faculty demographics including gender, age, position at the university, tenure status, and number of years faculty have taught in post-secondary education. There were no statistically significant relationships found between the top administrator-ranked motivators and corresponding faculty-ranked motivators, nor between the top administrator-ranked inhibitors and the corresponding faculty-ranked inhibitors. Out of the top four non-participating, faculty-ranked barriers, three were found to have statistically significant relationships with the corresponding administrator-ranked barriers. Statistically significant relationships were found between the faculty-ranked motivators and corresponding administrator identified motivators and between the top ranked barriers identified by non-participating faculty and administrators in Hebert’s study compared to non-participating faculty-ranked and administrator-ranked barriers identified in this study.
Date: May 2016
Creator: Bailey, Elizabeth
Partner: UNT Libraries

A Measurement of the Top Quark Mass in 1.96 TeV Proton-Antiproton Collisions Using a Novel Matrix Element Method

Description: A measurement of the top quark mass in t{bar t} {yields} l + jets candidate events, obtained from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncertainty of the jet momentum reconstruction. As with all matrix element techniques, the method involves an integration using the Standard Model matrix element for t{bar t} production and decay. However, the technique presented is unique in that the matrix element is modified to compensate for kinematic assumptions which are made to reduce computation time. Background events are dealt with through use of an event observable which distinguishes signal from background, as well as through a cut on the value of an event's maximum likelihood. Results are based on a 955 pb{sup -1} data sample, using events with a high-p{sub T} lepton and exactly four high-energy jets, at least one of which is tagged as coming from a b quark; 149 events pass all the selection requirements. They find M{sub meas} = 169.8 {+-} 2.3(stat.) {+-} 1.4(syst.) GeV/c{sup 2}.
Date: September 30, 2007
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department

Latino success stories in higher education: A qualitative study of recent graduates from a health science center.

Description: This study used qualitative research, particularly life history analysis, to determine the personal pathways of success for Latino students who chose to enter a health science center for graduate study and who graduated. By giving voice to individual success stories of Latino students, some of the influences on the life pathways of these graduates were determined. For the purposes of this study, success was defined as graduation from a health science center with either a doctor of philosophy, doctor of public health or doctor of osteopathic medicine degree. Four research subjects agreed to participate in this study from a possible 11 students from the graduating class of 2004-2005 at this health science center. Data were gathered through multiple in-depth interviews of the students themselves over a period of no more than one month for each participant. Data were analyzed using the mind mapping technique and Padilla's unfolding matrix. Findings indicate that each participant traveled a different pathway to achieve educational success although similarities did exist across participants. The influences of family background, cultural background, educational background and personal perceptions and goals did affect the pathways of these four Latino graduates. While three of four participants indicated that family was the most important influence on their academic success, all participants related the importance of family to their success, although their definitions of family seemed to vary and included the concepts of education, culture, and personal perceptions and goals. The concepts of family support of education and a culture of education within the family unit emerged as similar themes among study participants. Other similarities among participants were a high academic self-concept, a strong internal locus of control, the ability to create academic community, and a positive view of potentially negative situations. Individual themes emerged from the narratives within each category for each ...
Date: May 2007
Creator: Colley, Kay Lynne
Partner: UNT Libraries

Extreme ultraviolet lithography: A few more pieces of the puzzle

Description: The work described in this dissertation has improved three essential components of extreme ultraviolet (EUV) lithography: exposure tools, photoresist, and metrology. Exposure tools. A field-averaging illumination stage is presented that enables nonuniform, high-coherence sources to be used in applications where highly uniform illumination is required. In an EUV implementation, it is shown that the illuminator achieves a 6.5% peak-to-valley intensity variation across the entire design field of view. In addition, a design for a stand-alone EUV printing tool capable of delivering 15 nm half-pitch sinusoidal fringes with available sources, gratings and nano-positioning stages is presented. It is shown that the proposed design delivers a near zero line-edge-rougness (LER) aerial image, something extremely attractive for the application of resist testing. Photoresist. Two new methods of quantifying the deprotection blur of EUV photoresists are described and experimentally demonstrated. The deprotection blur, LER, and sensitivity parameters of several EUV photoresists are quantified simultaneously as base weight percent, photoacid generator (PAG) weight percent, and post-exposure bake (PEB) temperature are varied. Two surprising results are found: (1) changing base weight percent does not significantly affect the deprotection blur of EUV photoresist, and (2) increasing PAG weight percent can simultaneously reduce LER and E-size in EUV photoresist. The latter result motivates the development of an EUV exposure statistics model that includes the effects of photon shot noise, the PAG spatial distribution, and the changing of the PAG distribution during the exposure. In addition, a shot noise + deprotection blur model is used to show that as deprotection blur becomes large relative to the size of the printed feature, LER reduction from improved counting statistics becomes dominated by an increase in LER due to reduced deprotection contrast. Metrology. Finally, this dissertation describes MOSAIC, a new wavefront metrology that enables complete wavefront recovery from print or aerial image ...
Date: May 20, 2009
Creator: Anderson, Christopher N.
Partner: UNT Libraries Government Documents Department

Bayesian based design of real-time sensor systems for high-risk indoor contaminants

Description: The sudden release of toxic contaminants that reach indoor spaces can be hazardousto building occupants. To respond effectively, the contaminant release must be quicklydetected and characterized to determine unobserved parameters, such as release locationand strength. Characterizing the release requires solving an inverse problem. Designinga robust real-time sensor system that solves the inverse problem is challenging becausethe fate and transport of contaminants is complex, sensor information is limited andimperfect, and real-time estimation is computationally constrained.This dissertation uses a system-level approach, based on a Bayes Monte Carloframework, to develop sensor-system design concepts and methods. I describe threeinvestigations that explore complex relationships among sensors, network architecture,interpretation algorithms, and system performance. The investigations use data obtainedfrom tracer gas experiments conducted in a real building. The influence of individual sensor characteristics on the sensor-system performance for binary-type contaminant sensors is analyzed. Performance tradeoffs among sensor accuracy, threshold level and response time are identified; these attributes could not be inferred without a system-level analysis. For example, more accurate but slower sensors are found to outperform less accurate but faster sensors. Secondly, I investigate how the sensor-system performance can be understood in terms of contaminant transport processes and the model representation that is used to solve the inverse problem. The determination of release location and mass are shown to be related to and constrained by transport and mixing time scales. These time scales explain performance differences among different sensor networks. For example, the effect of longer sensor response times is comparably less for releases with longer mixing time scales. The third investigation explores how information fusion from heterogeneous sensors may improve the sensor-system performance and offset the need for more contaminant sensors. Physics- and algorithm-based frameworks are presented for selecting and fusing information from noncontaminant sensors. The frameworks are demonstrated with door-position sensors, which are found to ...
Date: December 1, 2007
Creator: Sreedharan, Priya & Sreedharan, Priya
Partner: UNT Libraries Government Documents Department

Intense Ion Beam for Warm Dense Matter Physics

Description: The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam intensity. We present results of beam transport through a solenoid matching section and simultaneous focusing of a singly charged K{sup +} ion bunch at an ion energy of 0.3 MeV. The results include a qualitative comparison of experimental and calculated results after the solenoid matching section, which include time resolved current density, transverse distributions, and phase-space of the beam at different diagnostic planes. Electron cloud and gas measurements in the solenoid lattice and in the vicinity of intercepting diagnostics are also presented. Finally, comparisons of improved experimental and calculated axial focus (> 100 x axial compression, < 2 ns pulses) ...
Date: May 23, 2008
Creator: Coleman, Joshua Eugene
Partner: UNT Libraries Government Documents Department