Theses and dissertations represent a wealth of scholarly and artistic content created by masters and doctoral students in the degree-seeking process. One of the first American universities to require ETDs for graduation, UNT began accepting theses and dissertations in electronic format in 1999.

	VLSI Architecture and FPGA Prototyping of a Secure Digital Camera for Biometric Application Date: 2006-08 Creator: Adamo, Oluwayomi Bamidele Description: This thesis presents a secure digital camera (SDC) that inserts biometric data into images found in forms of identification such as the newly proposed electronic passport. However, putting biometric data in passports makes the data vulnerable for theft, causing privacy related issues. An effective solution to combating unauthorized access such as skimming (obtaining data from the passport's owner who did not willingly submit the data) or eavesdropping (intercepting information as it moves from the chip to the reader) could be judicious use of watermarking and encryption at the source end of the biometric process in hardware like digital camera or scanners etc. To address such issues, a novel approach and its architecture in the framework of a digital camera, conceptualized as an SDC is presented. The SDC inserts biometric data into passport image with the aid of watermarking and encryption processes. The VLSI (very large scale integration) architecture of the functional units of the SDC such as watermarking and encryption unit is presented. The result of the hardware implementation of Rijndael advanced encryption standard (AES) and a discrete cosine transform (DCT) based visible and invisible watermarking algorithm is presented. The prototype chip can carry out simultaneous encryption and watermarking, which to our knowledge is the first of its kind. The encryption unit has a throughput of 500 Mbit/s and the visible and invisible watermarking unit has a max frequency of 96.31 MHz and 256 MHz respectively. > more info
	VO2 response profile in heavy intensity cycling after heavy intensity arm or leg exercise. Date: 2006-12 Creator: Ptak, April Louise Description: The elevated CO2 levels, elevated temperature, and lower blood pH that may occur during exercise should enhance O2 delivery to the exercising muscles. It was hypothesized that performance of prior exercise (PE) would result in a faster VO2 response, as well as a reduced slow component contribution, in subsequent exercise bouts. Five women (21 ± 1 yr) and 10 men (23 ± 2 yr) performed nine 6-min bouts of heavy intensity cycle ergometer exercise (i.e., above the ventilatory threshold, individually determined by an incremental test). Three bouts were performed without prior heavy exercise (noPE), three were performed 6 min after a 6-min bout of heavy intensity arm cranking (PEA), and three were performed 6 min after a 6-min bout of heavy intensity cycle ergometer exercise (PEL). Breath-by-breath VO2 data from each of the three sets of three tests were combined and fitted to a two-component model, which ignores the cardiodynamic phase. The primary and slow component amplitudes were truncated to reflect actual increases in VO2 in each phase. The effects of PE on the time constant of the primary component were inconsistent. As hypothesized, the amplitude of the slow component was reduced by PE (noPE vs PEA vs. PEL: 25% > 16% < 14%; p < .05). It is concluded that heavy intensity PE affects characteristics of the VO2 profile in a subsequent bout of heavy intensity leg exercise. > more info
	Validation of clinical screens for suicidality and severe mental disorders for jail inmates. Date: 2005-05 Creator: Harrison, Kimberly S. Description: Psychologists and other mental health professionals working in correctional institutions bear the considerable responsibility for identifying, diagnosing, and treating mentally disordered inmates. The importance of these responsibilities has been recognized in recent years because of the burgeoning population of inmates in general and the higher numbers of inmates with mental illness in particular. Research has demonstrated that the screens currently used in correctional settings to identify mentally disordered and suicidal inmates are either unvalidated or generally ineffective. This study investigates the validity of different mental health screens in a jail population. Inmates from the Grayson County Jail were administered three screens: the Referral Decision Scale (RDS), Personality Assessment Screener (PAS), and the Mental Disability/Suicide Intake Screen (MDSIS). Criterion measures were the Schedule for Affective Disorders and Schizophrenia (SADS) for Axis I disorders and the Suicide Probability Scale (SPS) for suicidal ideation. Results indicate that each screen most effectively assessed one clinical domain: the RDS for psychosis, the MDSIS for suicidality, and the PAS for depression. Gender differences were observed in screen items most effective for classifying inmates by suicide risk level. > more info
	Variability-aware low-power techniques for nanoscale mixed-signal circuits. Date: 2009-05 Creator: Ghai, Dhruva V. Description: New circuit design techniques that accommodate lower supply voltages necessary for portable systems need to be integrated into the semiconductor intellectual property (IP) core. Systems that once worked at 3.3 V or 2.5 V now need to work at 1.8 V or lower, without causing any performance degradation. Also, the fluctuation of device characteristics caused by process variation in nanometer technologies is seen as design yield loss. The numerous parasitic effects induced by layouts, especially for high-performance and high-speed circuits, pose a problem for IC design. Lack of exact layout information during circuit sizing leads to long design iterations involving time-consuming runs of complex tools. There is a strong need for low-power, high-performance, parasitic-aware and process-variation-tolerant circuit design. This dissertation proposes methodologies and techniques to achieve variability, power, performance, and parasitic-aware circuit designs. Three approaches are proposed: the single iteration automatic approach, the hybrid Monte Carlo and design of experiments (DOE) approach, and the corner-based approach. Widely used mixed-signal circuits such as analog-to-digital converter (ADC), voltage controlled oscillator (VCO), voltage level converter and active pixel sensor (APS) have been designed at nanoscale complementary metal oxide semiconductor (CMOS) and subjected to the proposed methodologies. The effectiveness of the proposed methodologies has been demonstrated through exhaustive simulations. Apart from these methodologies, the application of dual-oxide and dual-threshold techniques at circuit level in order to minimize power and leakage is also explored. > more info
	Variations of the Hand Test with young and older adults Date: 2001-08 Creator: Radika, Lisa M. Description: To explore the influence that variations in projective stimuli might have on the respondent's ability to identify with pictorial representations of hands derived from the Hand Test (Wagner, 1961, 1983), 61 young adults (M age = 23) and 60 older adults (M age = 73) were presented with four alternate versions of hand stimuli (young male, young female, old male, and old female) in addition to the original Hand Test. Results indicated main effects for age and gender of respondent, which were primarily consistent with previous Hand Test research. Main effects for gender and age of hand stimuli (p < .05) were also found. Significant interaction effects were revealed for age of respondent by age of hand stimuli and for age of respondent by gender of hand stimuli (p < .05). These interactions resulted in the elicitation of a variety of responses to a differentiated manner than a standard set of Hand Test stimuli. A gender of respondent by gender of hand stimuli interaction effect was also found (p &lt; .05), suggesting that gender alterations of the card may also be beneficial for increasing respondent identification for some individuals. Overall, the results of variations in Hand Test stimuli, as they interact with respondent personal characteristics, indicate the utility of alternate versions of the Hand Test. This is based on the assumption that the respondent will identify with the hand that best resembles his/her hands, resulting in the stimulus performing its projective function to a greater extent. > more info | Use restricted to UNT community
	Viability of the job characteristics model in a team environment: Prediction of job satisfaction and potential moderators. Date: 2006-12 Creator: Hunter, Philip Edward Description: Much of the history of management and motivation theory is rooted in the desire to understand the factors that contribute to having a satisfied workforce. Job satisfaction is the most widely studied construct in the history of industrial/organizational psychology. The job characteristics model (JCM) holds that if jobs are enriched with high levels of specific job characteristics (i.e., task significance, task variety, task identity, autonomy and feedback), employees will report higher levels of job satisfaction. While this claim enjoys wide support in studies conducted in traditional, hierarchically based organizational environments, few studies have tested the JCM in team based organizational designs. This study also evaluated possible moderating influences of growth need strength (GNS; the need for personal growth and development within the job environment) and emotional reactivity (a measure of frustration with perceived obstacles in the work environment). It was hypothesized that employees with higher levels of GNS would respond more positively (via higher job satisfaction ratings) to enriched jobs than would employees with lower levels of GNS. Alternatively, it was hypothesized that employees with lower levels of emotional reactivity would respond more positively (via higher job satisfaction ratings) to enriched jobs than would employees with higher levels of emotional reactivity. Results indicated that four job characteristics (task significance, task variety, task identity and feedback) served as significant positive predictors of job satisfaction, while GNS moderated the relationships between task significance and task variety with job satisfaction in a way that supported the research hypothesis. Emotional reactivity was not found to moderate any of the relationships between individual job characteristics and job satisfaction. Overall, results support the relevance of the JCM to team based organizations, providing support for the assertion that the relationship between enriched jobs and higher levels of job satisfaction persists across professional work contexts, as well as the partial moderating influence of GNS. > more info
	Vicarious Learning: The Relationship Between Perceived Leader Behavior and Work Group Member Behavior Date: 2002-12 Creator: Brown, Diem Description: The relationship between perceived leader behavior and work group behavior was examined. Archival survey data was used in the analyses. The company that developed the survey randomly selected 595 employees to complete the survey. Results suggest there is a strong and significant relationship between leader and subordinate behavior. Group members who report that their leader demonstrates a particular behavior also report that their work group demonstrates the same or similar behavior, suggesting that subordinates may be modeling the behavior of their leader. Leadership behaviors related to trust, availability, respect, conflict, and support seem to be the best predictors of work group behavior. Furthermore, whether or not group members have received team training appears to have an effect on their perceptions of their leader and work group. The challenge for leaders is to understand modeling principles so that they can facilitate the modeling of functional rather than dysfunctional behaviors. > more info
	Vicarious traumatization, secondary traumatic stress, and burnout in sexual assault and domestic violence agency staff and volunteers Date: 1999-08 Creator: Baird, Stephanie Description: Two constructs, vicarious trauma (VT) and secondary traumatic stress (STS), describe therapists’ reactions to clients’ traumatic material. VT (TSI Belief Scale [BSL]), emphasizes cognitive belief system changes resulting from cumulative exposure to survivors. STS, (Compassion Fatigue Self-test for Psychotherapists [CFST]) combines PTSD and burnout symptomatology explaining sudden adverse reactions to survivors. Burnout (BO; Maslach Burnout Inventory [MBI]), links emotional exhaustion, depersonalization, and deficient personal accomplishment to inadequate institutional supports in interpersonally demanding work. This study investigated BSL and CFST validity, counselor trauma history, and client exposure-related VT, STS, and BO in 105 trauma counselors. Results demonstrate concurrent validity between BSL and CFST; other results dispute adequate validity. BO, and client exposure were related. Traumatized counselors scored higher than non-traumatized counselors on CFST, BSL, and SCL-90-R. > more info
	Victims of Hope: Explaining Jewish Behavior in the Treblinka, Sobibór and Birkenau Extermination Camps Date: 2000-08 Creator: Motl, Kevin C. Description: I analyze the behavior of Jews imprisoned in the Treblinka, Sobibór, and Birkenau extermination camps in order to illustrate a systematic process of deception and psychological conditioning, which the Nazis employed during World War II to preclude Jewish resistance to the Final Solution. In Chapter I, I present resistance historiography as it has developed since the end of the war. In Chapter II, I delineate my own argument on Jewish behavior during the Final Solution, limiting my definition of resistance and the applicability of my thesis to behavior in the extermination camp, or closed, environment. In Chapters III, IV, and V, I present a detailed narrative of the Treblinka, Sobibór, and Birkenau revolts using secondary sources and selected survivor testimony. Finally, in Chapter VI, I isolate select parts of the previous narratives and apply my argument to demonstrate its validity as an explanation for Jewish behavior. > more info | Use restricted to UNT community
	Vieques: Island of Conflict and Dreams Date: 2003-12 Creator: Borges, Cristóbal A. Description: This written thesis is a companion to a 30-minute documentary video of the same title. The documentary is a presentation of the historical conflict between the United States Navy and the people of the island of Vieques, Puerto Rico. For over 60 years the island was used by the United States Navy as a military training facility. The documentary attempts to present an analysis of the struggle between citizens of the island and the Navy. This written component presents a summarized history of Puerto Rico, Vieques and the conflict with the United States Navy. In addition, the preproduction, production and post-production process of the documentary are discussed. A theoretical analysis of the filmmaker's approach and technique are addressed and analyzed as well. The thesis's goal is to provide a clear understanding of the Vieques conflict to United States audiences who do not a familiarity with the topic. The thesis is presented from the perspective of a person who grew up in Puerto Rico. > more info