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open access

Analyzing the Effects of a Performance Pay Plan on Manager Performance in an Accounting Firm

Description: This study examined the effect of a score card¬-based performance pay plan in a professional services firm. The plan was implemented in response to a decreasing trend in productivity and a desire for a formal incentive compensation plan. Performance of manager and senior manager accountants were analyzed across two departments over a five year period. A definitive account of the effects of the intervention is limited by the case-¬study design, but the data does suggest that the performance pay plans used did not adversely affect performances. Design limitations of the plan and future research are also discussed.
Date: May 2007
Creator: McDaniel, Sarah Curran
Partner: UNT Libraries
open access

Conditional Discrimination and Stimulus Equivalence: Effects of Suppressing Derived Symmetrical Responses on the Emergence of Transitivity.

Description: Symmetry suppression was conducted for five subjects who demonstrated a tendency to derive equivalence relations based on conditional discrimination training in a match-to-sample procedure. Symmetry suppression was applied in three consecutive sessions in which symmetrical responses were suppressed for one stimulus class in the first condition, two stimulus classes in the second condition, and all three stimulus classes in the final condition. Symmetry suppression slowed the emergence of transitivity for two subjects and prevented it for the other three. Results indicated that unplanned features of stimulus configurations emerged as discriminative variables that controlled selection responses and altered the function of consequent stimuli. Disruption of cognitive development by conflicting contingencies in natural learning environments is discussed.
Date: May 2007
Creator: Jones, Aaron A.
Partner: UNT Libraries
open access

FPGA Prototyping of a Watermarking Algorithm for MPEG-4

Description: In the immediate future, multimedia product distribution through the Internet will become main stream. However, it can also have the side effect of unauthorized duplication and distribution of multimedia products. That effect could be a critical challenge to the legal ownership of copyright and intellectual property. Many schemes have been proposed to address these issues; one is digital watermarking which is appropriate for image and video copyright protection. Videos distributed via the Internet must be processed by compression for low bit rate, due to bandwidth limitations. The most widely adapted video compression standard is MPEG-4. Discrete cosine transform (DCT) domain watermarking is a secure algorithm which could survive video compression procedures and, most importantly, attacks attempting to remove the watermark, with a visibly degraded video quality result after the watermark attacks. For a commercial broadcasting video system, real-time response is always required. For this reason, an FPGA hardware implementation is studied in this work. This thesis deals with video compression, watermarking algorithms and their hardware implementation with FPGAs. A prototyping VLSI architecture will implement video compression and watermarking algorithms with the FPGA. The prototype is evaluated with video and watermarking quality metrics. Finally, it is seen that the video qualities of the watermarking at the uncompressed vs. the compressed domain are only 1dB of PSNR lower. However, the cost of compressed domain watermarking is the complexity of drift compensation for canceling the drifting effect.
Date: May 2007
Creator: Cai, Wei
Partner: UNT Libraries
open access

Study of Substituted Benzenesulfonate-Containing Layered Double Hydroxides and Investigation of the Hexamethylenetetramine Route of LDH Synthesis

Description: Benzenesulfonates, para-substituted with amine, chloride and methyl groups were successfully incorporated into layered double hydroxides of two different compositions, 2:1 Mg-Al LDH and 2:1 Zn-Al LDH. These parent materials were also doped with small amounts of nickel and the differences in the two systems were studied. The hexamethylenetetramine route of layered double hydroxide synthesis was investigated to verify if the mechanism is indeed homogeneous. This included attempting preparation of 2:1 Mg-Al LDH, 2:1 Zn-Al LDH and 2:1 Zn-Cr LDH with two different concentrations of hexamethylenetetramine. The analytical data of the products suggest that the homogeneous precipitation may not be the true mechanism of reaction involved in LDH synthesis by this method.
Date: May 2007
Creator: Ambadapadi, Sriram
Partner: UNT Libraries
open access

What's Real Anymore: A Comparison of World of Warcraft, SecondLife and Online Experiences

Description: The proliferation of the Internet and online-based social interactions has become an increasingly popular topic with communication scholars. The goal of this study was to explore how massively multi-player online role playing game (MMORPG) players make sense of and negotiate their online social interactions. This study (N = 292) examined how players of SecondLife and World of Warcraft evaluated their online relationships compared to their offline relationships and investigated how different levels of realism within different MMORPGs effected player's online experiences. The results indicated that players of SecondLife placed higher values of emotional closeness to their online relationships when compared to players of World of Warcraft and SecondLife was rated more real by its players than World of Warcraft. Results further indicated that players of SecondLife had higher levels of perceived online emotional closeness when compared to perceived offline emotional closeness. Implications of this study focus on developing a bottom up holistic profile of online game players as opposed to the current top down research model.
Date: May 2009
Creator: Tran, Chris
Partner: UNT Libraries
open access

Developing a Wildlife Tracking Extension for ArcGIS

Description: Wildlife tracking is an essential task to gain better understanding of the migration pattern and use of space of the wildlife. Advances in computer technology and global positioning systems (GPS) have lowered costs, reduced processing time, and improved accuracy for tracking wild animals. In this thesis, a wildlife tracking extension is developed for ArcGIS 9.x, which allows biologists and ecologists to effectively track, visualize and analyze the movement patterns of wild animals. The extension has four major components: (1) data import; (2) tracking; (3) spatial and temporal analysis; and (4) data export. Compared with existing software tools for wildlife tracking, the major features of the extension include: (1) wildlife tracking capabilities using a dynamic data layer supported by a file geodatabase with 1 TB storage limit; (2) spatial clustering of wildlife locations; (3) lacunarity analysis of one-dimensional individual animal trajectories and two-dimensional animal locations for better understanding of animal movement patterns; and (4) herds evolvement modeling and graphic representation. The application of the extension is demonstrated using simulated data, test data collected by a GPS collar, and a real dataset collected by ARGOS satellite telemetry for albatrosses in the Pacific Ocean.
Date: May 2009
Creator: Chen, Cai
Partner: UNT Libraries
open access

No place to call home: Cultural homelessness, self-esteem and cross-cultural identities.

Description: The study examined relations between a cross-cultural geographically mobile childhood and adult cultural identity, attachment to cross-cultural identities (CCIs) and self-esteem. CCIs are loosely defined identities (e.g., third culture kids [TCKs], military brats, missionary kids) that describe some individuals' childhood cross-cultural experience. The 475 participants spent at least two years before age 18 in a culture different from their parents' and completed an online survey including childhood cross-cultural experiences, Cultural Homelessness Criteria, Rosenberg Self-esteem Scale, and Self Label Identity Measure (SLIM) that captured strength of affirmation, belonging and commitment to any CCI. Cultural homelessness (CH) was related to lower self-esteem; higher SLIM scores was related to higher self-esteem and lower CH. TCKs reported lower self-esteem than non-TCKs and older participants experienced less CH and higher self-esteem. SLIM scores buffered the CH-self-esteem relationship, whereas a TCK CCI and having more cross-culturally experienced social networks did not.
Date: May 2009
Creator: Hoersting, Raquel Carvalho
Partner: UNT Libraries
open access

FPGA Implementation of Low Density Party Check Codes Decoder

Description: Reliable communication over the noisy channel has become one of the major concerns in the field of digital wireless communications. The low density parity check codes (LDPC) has gained lot of attention recently because of their excellent error-correcting capacity. It was first proposed by Robert G. Gallager in 1960. LDPC codes belong to the class of linear block codes. Near capacity performance is achievable on a large collection of data transmission and storage.In my thesis I have focused on hardware implementation of (3, 6) - regular LDPC codes. A fully parallel decoder will require too high complexity of hardware realization. Partly parallel decoder has the advantage of effective compromise between decoding throughput and high hardware complexity. The decoding of the codeword follows the belief propagation alias probability propagation algorithm in log domain. A 9216 bit, (3, 6) regular LDPC code with code rate ½ was implemented on FPGA targeting Xilinx Virtex 4 XC4VLX80 device with package FF1148. This decoder achieves a maximum throughput of 82 Mbps. The entire model was designed in VHDL in the Xilinx ISE 9.2 environment.
Date: August 2009
Creator: Vijayakumar, Suresh
Partner: UNT Libraries
open access

What you teach makes a difference: Direct and collateral outcomes of an autism sibling intervention.

Description: Training siblings as change agents for children diagnosed with autism spectrum disorders (ASD) has been shown to be beneficial in teaching a sibling to teach their brother or sister. There are very few interventions, however, that explore the range of effects that targeting particular skills has on sibling interactions. The purpose of this study was to assess the direct and collateral effects of training behavioral teaching techniques to a typically developing sibling. Four experimental conditions were assessed: baseline, sibling teaching toy play, baseline, and sibling teaching social play. Across all conditions, measures of teaching components and siblings' interactions were assessed. Results of the assessment showed that the sibling was an effective change agent and that more favorable interaction and engagement occurred when social play skills were taught. The results of this sibling intervention and guidelines for condition changes are discussed in terms of sibling relationships.
Date: May 2009
Creator: Czekalski, Sara
Partner: UNT Libraries
open access

Immediate and Subsequent Effects of Fixed-Time Delivery of Therapist Attention on Problem Behavior Maintained by Attention

Description: The purpose of the current study was to investigate the immediate and subsequent effects of fixed-time attention on problem behavior maintained by therapist attention utilizing a three-component multiple-schedule design. The treatment analysis indicated that fixed-time attention produced a significant immediate decrease in the frequency of physically disruptive behavior (PDB), represented by low frequencies of PDB in Component 2, as well as a continued subsequent effect, represented by lower frequencies of problem behavior in Component 3 when compared to Component 1. The possible behavioral mechanisms responsible for the observed suppression in Component 2 of the treatment analysis are discussed. Evidence of behavioral contrast was observed in Components 1 and 3 of the treatment analysis in conditions in which Component 2 contained a fixed-time schedule of stimulus delivery. In addition, limitations and future research are outlined.
Date: August 2009
Creator: Walker, Stephen Frank
Partner: UNT Libraries
open access

The Effects of PECS Training on Symbolic Matching Skills in Learners with Autism

Description: This study evaluated whether picture exchange communication system (PECS) training would result in the development of conditional relations among corresponding pictures, objects (reinforcers) and spoken words used in PECS training with learners with developmental disabilities. Three participants with autism and mental retardation were trained to use PECS. Match-to-sample procedures were used to assess all possible conditional relations among stimuli before, during, and after PECS training. None of the three participants in this study acquired conditional discriminations involving the pictures, reinforcers, and spoken words used in their PECS training.
Date: May 2009
Creator: Cranmer, Elizabeth
Partner: UNT Libraries
open access

Factor Structure of the Neurocognitive Battery in a Geriatric Sample with Cognitive Impairments

Description: The present study was designed to empirically validate six theoretically derived cognitive domains (verbal memory, visual memory, working memory, attention-concentration, executive functions, and visuospatial abilities) assessed by a comprehensive battery of neuropsychological tests used in the Geriatric Memory Clinic at the University of North Texas Health Science Center in Fort Worth, Texas. The study examined the extent to which various cognitive dimensions are tapped by this battery in a heterogeneous geriatric sample of 114 patients with cognitive impairments. The proposed six-factor model of cognitive functioning has not been supported. Further exploratory factor analysis arrived at a five-factor solution. Factor pattern of the 23 tests supported the following five dimensions: memory, executive control, attention, visuospatial abilities, and cognitive flexibility.
Date: May 2007
Creator: Serova, Svetlana
Partner: UNT Libraries
open access

A nano-CMOS based universal voltage level converter for multi-VDD SoCs.

Description: Power dissipation of integrated circuits is the most demanding issue for very large scale integration (VLSI) design engineers, especially for portable and mobile applications. Use of multiple supply voltages systems, which employs level converter between two voltage islands is one of the most effective ways to reduce power consumption. In this thesis work, a unique level converter known as universal level converter (ULC), capable of four distinct level converting operations, is proposed. The schematic and layout of ULC are built and simulated using CADENCE. The ULC is characterized by performing three analysis such as parametric, power, and load analysis which prove that the design has an average power consumption reduction of about 85-97% and capable of producing stable output at low voltages like 0.45V even under varying load conditions.
Date: May 2007
Creator: Vadlmudi, Tripurasuparna
Partner: UNT Libraries
open access

Criminal Investigations: The Impact of Patrol Officers on Solving Crime

Description: This two-part study of the criminal investigation process first evaluated the frequency with which patrol officers solve cases assigned to the investigations division and then examined how detectives spent their time, both on case assignments and on other activity not related to current case assignment. Cases assigned to the investigations division for follow up were examined to determine how often a case was cleared by the patrol officer. The detective's time was then evaluated in order to determine how much time detectives spent on investigative tasks and other activities. This study confirms that the patrol officer should be given more time to conduct preliminary investigations for specific cases, and that tasks performed by detectives could be shifted to other personnel in the department. Both actions should serve to positively impact case clearance rates.
Date: May 2007
Creator: Womack, Charissa L.
Partner: UNT Libraries
open access

Multiple-respondent anecdotal assessments for behavior disorders; An analysis of interrater agreement and correspondence with treatment outcomes.

Description: The current study was designed to further evaluate the usefulness of anecdotal assessments. The goal of this study was to evaluate the overall agreement between multiple respondents on the primary function of aberrant behavior using the Motivation Assessment Scale (MAS) and the Functional Analysis Screening Tool (FAST) and, if agreement was obtained, to assess the effectiveness of treatment based on the outcome of the assessments. Results showed that anecdotal assessments were able to identify the general type of contingency maintaining two participants' problem behavior. However, for one participant the assessments did not correctly identify the specific form of reinforcement (attention or tangible items) that maintained the aberrant behavior.
Date: May 2007
Creator: Wolf, Roxanne
Partner: UNT Libraries
open access

Preliminary design of a cryogenic thermoelectric generator.

Description: A cryogenic thermoelectric generator is proposed to increase the efficiency of a vehicle propulsion system that uses liquid nitrogen as its fuel. The proposed design captures some of the heat required for vaporizing or initial heating of the liquid nitrogen to produce electricity. The thermoelectric generator uses pressurized liquid nitrogen as its cold reservoir and ambient air as the high-temperature reservoir to generate power. This study concentrated on the selection of thermoelectric materials whose properties would result in the highest efficiency over the operating temperature range and on estimating the initial size of the generator. The preliminary selection of materials is based upon their figure of merit at the operating temperatures. The results of this preliminary design investigation of the cryogenic thermoelectric generator indicate that sufficient additional energy can be used to increase overall efficiency of the thermodynamic cycle of a vehicle propulsion system.
Date: May 2007
Creator: Sivapurapu, Sai Vinay Kumar
Partner: UNT Libraries
open access

Map-based cloning of the NIP gene in model legume Medicago truncatula.

Description: Large amounts of industrial fertilizers are used to maximize crop yields. Unfortunately, they are not completely consumed by plants; consequently, this leads to soil pollution and negative effects on aquatic systems. An alternative to industrial fertilizers can be found in legume plants that provide a nitrogen source that is not harmful for the environment. Legume plants, through their symbiosis with soil bacteria called rhizobia, are able to reduce atmospheric nitrogen into ammonia, a biological nitrogen source. Establishment of the symbiosis requires communication on the molecular level between the two symbionts, which leads to changes on the cellular level and ultimately results in nitrogen-fixing nodule development. Inside the nodules hypoxic environment, the bacterial enzyme nitrogenase reduces atmospheric nitrogen to ammonia. Medicago truncatula is the model legume plant that is used to study symbiosis with mycorrhiza and with the bacteria Sinorhizobium meliloti. The focus of this work is the M. truncatula nodulation mutant nip (numerous infections and polyphenolics). The NIP gene plays a role in the formation and differentiation of nodules, and development of lateral roots. Studying this mutant will contribute knowledge to understanding the plant response to infection and how the invasion by rhizobia is regulated. Previous genetic mapping placed NIP at the top of linkage group 1 of the M. truncatula genome. A NIP mapping population was established with the purpose of performing fine mapping in the region containing NIP. DNA from two M. truncatula ecotypes A17 and A20 can be distinguished through polymorphisms. Positional mapping of the NIP gene is based on the A17/A20 genetic map of M. truncatula. The NIP mapping population of 2277 plants was scored for their nodulation phenotype and genotyped with flanking molecular genetic markers 146o17 and 23c16d, which are located ~1.5 cM apart and on either side of NIP. This resulted in the identification …
Date: May 2007
Creator: Morris, Viktoriya
Partner: UNT Libraries
open access

A Study of Standards for Industrial Arts Housing Facilities for Industrial Arts at Arlington Heights Senior High School, Fort Worth, Texas

Description: This is a study of the standards and current practices as related to housing facilities for industrial arts programs with recommendations concerning the proposed housing facilities for industrial arts in the Arlington Heights Senior High School, Fort Worth, Texas, based upon present and future estimated scholastic enrollment and accepted standards and practices.
Date: 1953
Creator: Wylie, Harry V.
Partner: UNT Libraries
open access

The Development of Teaching Aids for Elementary Electricity

Description: The purpose of this study is to develop a teaching program of instructional aids which will enrich the teaching of elementary electricity in the junior and senior high schools. It is hoped that the information and materials developed and presented will be of practical value to the teachers engaged in the teaching of electricity.
Date: 1953
Creator: Briggs, Cecil Lee
Partner: UNT Libraries
open access

A Study of a Selected Number of Stories Suitable for Dramatization in the Third Grade

Description: The writer purposes to discover the types of stories that appeal to the interest and imagination of children of the third grade, and to determine whether the literary qualities and the dramatic possibilities of the stories are within the understanding and ability of the group.
Date: 1948
Creator: Putnam, Gustave
Partner: UNT Libraries
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