UNT Theses and Dissertations - Browse

A Preliminary Controller Design for Drone Carried Directional Communication System
In this thesis, we conduct a preliminary study on the controller design for directional antenna devices carried by drones. The goal of the control system is to ensure the best alignment between two directional antennas so as to enhance the performance of air-to-air communication between the drones. The control system at the current stage relies on the information received from GPS devices. The control system includes two loops: velocity loop and position loop to suppress wind disturbances and to assure the alignment of two directional antennae. The simulation and animation of directional antennae alignment control for two-randomly moving drones was developed using SIMULINK. To facilitate RSSI-based antenna alignment control to be conducted in the future work, a study on initial scanning techniques is also included at the end of this thesis.
My Whine, Your Wine
Grapes hold the flavors of the lands where they grow, and when you make wine from them, those flavors of the land come through. Tasting wine from a place you've been can bring you back to that place with aromas and notes indicative of that place. A bottle of wine changes every day, and how it will taste depends on the moment you choose to release it from the glass walls. I have a vested interest in wine, because it is a living thing. I am compelled to make wine because its characteristics are like personality traits. Although some of those characteristics are harsh at times, I appreciate them all. Each trait plays an important role in the balance, the overall personality. Like my own personality flaws, wine's harsh tones can smooth over time. My relationship with wine is constantly evolving, with every new varietal, vintage, batch and blend. Believe me, after some of the jobs I had before my first day at Su Vino, I cherish every moment of my winemaking career. My Whine, Your Wine is the story of how it all started.
Interfacial Characterization of Chemical Vapor Deposition (Cvd) Grown Graphene and Electrodeposited Bismuth on Ruthenium Surface
Graphene receives enormous attention owing to its distinctive physical and chemical prosperities. Growing and transferring graphene to different substrates have been investigated. The graphene growing on the copper substrate has an advantage of low solubility of carbon on the copper which allow us to grow mostly monolayer graphene. Graphene sheet of few centimeters can be transferred to 300nm silicon oxide and quartz crystal pre-deposited with metal like Cu and Ru. Characterization of the graphene has been done with Raman and contact angle measurement and recently quartz crystal microbalance (QCM) has been employed. The underpotential deposition (UPD) process of Bi on Ru metal surface is studied using electrochemical quartz crystal microbalance (EQCM) and XPS techniques. Both Bi UPD and Bi bulk deposition are clearly observed on Ru in 1mM Bi (NO3)3/0.5M H2SO4. Bi monolayer coverage calculated from mass (MLMass) and from charge (MLCharge) were compared with respect to the potential scanning rates, anions and ambient controls. EQCM results indicate that Bi UPD on Ru is mostly scan rate independent but exhibits interesting difference at the slower scan. Bi UPD monolayer coverage calculated from cathodic frequency change (ΔfCathodic) is significantly smaller than the monolayer coverage derived from integrated charge under the cathodic Bi UPD peak when scan rate is at least 5 mV/s. XPS is utilized to explore the detailed chemical composition of the observed interfacial process of Bi UPD on Ru.
Derivation of the Thematic Material and Intervallic Gestures From the Main Theme in Fantasia Carioca By Sérgio Assad
The quantity of classical guitar literature reached a new peak late in the twentieth century with many famous guitarists publishing their own works for solo classical guitar. This increase in the published guitar literature resulted in a decline of the relative analytical discussions of contemporary guitar works. Sérgio Assad is a perfect example of an active guitarist/composer whose works are frequently performed in guitar recitals and yet very little discussion has been provided attempting to gain a deeper understanding of his compositional language. The purpose of this study is to two-fold: first, to show that Fantasia Carioca (1994) is a very carefully organized work and includes an intricate network of thematic material developed through a spectrum of intervallic gestures, of which all derive from the main theme of the piece; second, to provide a deeper insight into the compositional language of Sérgio Assad through a demonstration of different compositional procedures to which the composer resorts. This one-movement piece reveals a high level of organization present in Sérgio Assad's style. The entire thematic material is carefully derived from the main theme. Each thematic unit shows a set of predetermined characteristics that allow these units to react to particular textures and situations. The thematic organization is interwoven with important intervallic gestures and relationships, which lead the development of the thematic material. The insight into the applied techniques and structural elements provides a highly beneficial pool of information for anybody who decides to perform this piece. The offered arguments also serve as a good starting point for further analytical approaches and examinations of the growing oeuvre of Assad's classical guitar music.
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 mode model was two days and two hours from each experiment, while for the heating mode it was four days and two hours from each experiment.
Cognitive Engagement in Later Life: Descriptive and Explanatory Findings
Findings on the relationship between engagement in lifestyle and cognitive functioning are not consistent; some authors report that engagement in lifestyle predicts an individual's cognitive functioning; while other report that an individual's cognitive functioning predicts the type and level of engagement an individual participates in. The current study will use longitudinal data (N = 235) to investigate the bidirectional relationship between engagement (engaged lifestyle activities) and cognition (crystallized & fluid intelligence). Despite inconsistent findings it is proposed that cognitive functioning may be better understood when examining how stimulation of activity, need for cognition, and openness to experience affect engagement in an active lifestyle. As such the current study will investigate if stimulation of activity, need for cognition, and openness to experience moderate the relationship between engaged lifestyles and cognitive functioning. The results, limitations and implications are discussed.
Jacques-Antoine-Hippolyte, comte de Guibert: Father of the Grande Armée
The eighteenth century was a time of intense upheaval in France. The death of Louis XIV in 1715 and the subsequent reign of Louis XV saw the end of French political and martial hegemony on the continent. While French culture and language remained dominant in Europe, Louis XV's disinterested rule and military stagnation led to the disastrous defeat of the French army at the hands of Frederick the Great of Prussia in the Seven Years War (1756-1763). The battle of Rossbach marked the nadir of the French army in the Seven Years War. Frederick's army routed the French infantry that had bumbled its way into massed Prussian cavalry. Following the war, two reformist elements emerged in the army. Reformers within the government, chiefly Etienne François, duc de Choiseul, sought to rectify the army's poor performance and reconstitute France's military establishment. Outside the traditional army structure, military thinkers looked to military theory to reinvigorate the army from within and without. Foremost among the latter was a young officer named Jacques-Antoine-Hippolyte de Guibert, whose 1772 Essai général de tactique quickly became the most celebrated work of theory in European military circles. The Essai provided a new military constitution for France, proposing wholesale reform to create an army that could face the Prussian juggernaut. His star quickly rising, Guibert became the toast not only of literary Paris but all of Europe. Guibert exerted an overwhelming influence on military theory across Europe for the next fifty years. His military theories laid the foundation for the French army of the Revolutionary and Napoleonic eras. As other nations adopted French methods, Guibert's influence spread across the continent, reigning supreme until the 1830s. Guibert's importance to military theory is analogous to Voltaire's influence on European literature and culture, an area in which Guibert was not unfamiliar. Guibert ...
Jacques-Antoine-Hippolyte, Comte De Guibert: Father of the Grande Armée
Jacques-Antoine-Hippolyte, comte de Guibert (1743-1790) dedicated his life and career to creating a new doctrine for the French army. Little about this doctrine was revolutionary. Indeed, Guibert openly decried the anarchy of popular participation in government and looked askance at the early days of the Revolution. Rather, Guibert’s doctrine marked the culmination of an evolutionary process that commenced decades before his time and reached fruition in the Réglement of 1791, which remained in force until the 1830s. Not content with military reform, Guibert demanded a political and social constitution to match. His reforms required these changes, demanding a disciplined, service-oriented society and a functional, rational government to assist his reformed military. He delved deeply, like no other contemporary writer, into the linkages between society, politics, and the military throughout his career and his writings. Guibert exerted an overwhelming influence on military thought across Europe for the next fifty years. His military theories provided the foundation for military reform during the twilight of the Old Regime. The Revolution, which adopted most of Guibert’s doctrine in 1791, continued his work. A new army and way of war based on Guibert’s reforms emerged to defeat France’s major enemies. In Napoleon’s hands, Guibert’s army all but conquered Europe by 1807. As other nations adopted French methods, Guibert’s influence spread across the Continent, reigning supreme until the 1830s. This dissertation adopts a biographical approach to examine Guibert’s life and influence on the creation of the French military system that led to Napoleon’s conquest of Europe. As no such biography exists in Anglophone literature, such a work will fill a crucial gap in understanding French military success to 1807. It examines the period of French military reform from 1760 to the creation and use of Napoleon’s Grande Armée from 1803 to 1807, illustrating the importance of ...
Source Apportionment Analysis of Measured Volatile Organic Compounds in Corpus Christi, Texas
Corpus Christi among of the largest industrialized coastal urban areas in Texas. The strategic location of the city along the Gulf of Mexico allows for many important industries and an international business to be located. The cluster of industries and businesses in the region contribute to the air pollution from emissions that are harmful to the environment and to the people living in and visiting the area. Volatile organic compounds (VOC) constitute an important class of pollutants measured in the area. The automated gas chromatography (Auto GC) data was collected from Texas Commission of Environmental Quality (TCEQ) and source apportionment analysis was conducted on this data to identify key sources of VOC affecting this study region. EPA PMF 3.0 was employed in this sources apportionment study of measured VOC concentration during 2005 - 2012 in Corpus Christi, Texas. The study identified nine optimal factors (Source) that could explain the concentration of VOC at two urbane monitoring sites in the study region. Natural gas was found to be the largest contributor of VOC in the area, followed by gasoline and vehicular exhaust. Diesel was the third highest contributor with emissions from manufacturing and combustion processes. Refineries gases and evaporative fugitive emissions were other major contributors in the area; Flaring operations, solvents, and petrochemicals also impacted the measured VOC in the urban area. It was noted that he measured VOC concentrations were significantly influenced by the economic downturn in the region and this was highlighted in the annual trends of the apportioned VOC.
Boosting for Learning From Imbalanced, Multiclass Data Sets
In many real-world applications, it is common to have uneven number of examples among multiple classes. The data imbalance, however, usually complicates the learning process, especially for the minority classes, and results in deteriorated performance. Boosting methods were proposed to handle the imbalance problem. These methods need elongated training time and require diversity among the classifiers of the ensemble to achieve improved performance. Additionally, extending the boosting method to handle multi-class data sets is not straightforward. Examples of applications that suffer from imbalanced multi-class data can be found in face recognition, where tens of classes exist, and in capsule endoscopy, which suffers massive imbalance between the classes. This dissertation introduces RegBoost, a new boosting framework to address the imbalanced, multi-class problems. This method applies a weighted stratified sampling technique and incorporates a regularization term that accommodates multi-class data sets and automatically determines the error bound of each base classifier. The regularization parameter penalizes the classifier when it misclassifies instances that were correctly classified in the previous iteration. The parameter additionally reduces the bias towards majority classes. Experiments are conducted using 12 diverse data sets with moderate to high imbalance ratios. The results demonstrate superior performance of the proposed method compared to several state-of-the-art algorithms for imbalanced, multi-class classification problems. More importantly, the sensitivity improvement of the minority classes using RegBoost is accompanied with the improvement of the overall accuracy for all classes. With unpredictability regularization, a diverse group of classifiers are created and the maximum accuracy improvement reaches above 24%. Using stratified undersampling, RegBoost exhibits the best efficiency. The reduction in computational cost is significant reaching above 50%. As the volume of training data increase, the gain of efficiency with the proposed method becomes more significant.
Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications
Poor air quality can greatly affect the public health. Research studies indicate that indoor air can be more polluted than the outdoor air. An indoor air quality monitoring system will help to create an awareness of the quality of air inside which will eventually help in improving it. The objective of this research is to develop a low cost wireless sensor system for indoor air quality monitoring. The major cost reduction of the system is achieved by using low priced sensors. Interface circuits had to be designed to make these sensors more accurate. The system is capable of measuring carbon dioxide, carbon monoxide, ozone, temperature, humidity and volatile organic compounds. The prototype sensor node modules were developed. The sensor nodes were the connected together by Zigbee network. The nodes were developed in such a way that it is compact in size and wireless connection of sensor nodes enable to collect air quality data from multiple locations simultaneously. The collected data was stored in a computer. We employed linear least-square approach for the calibration of each sensor to derive a conversion formula for converting the sensor readings to engineering units. The system was tested with different pollutants and data collected was compared with a professional grade monitoring system for analyzing its performance. The results indicated that the data from our system matched quite well with the professional grade monitoring system.
Ultrafast Laser Sampling of a Plant Tissue and ion Conductivity Measurement for Investigation of Light Stress Generation Mechanisms
In this study we applied ultra-short laser pulses on a biological sample (Arabidopsis), in order to cut it precisely in a square pattern and subsequently use it for studying stress generation mechanisms. For this purpose, we utilized femtosecond laser pulses at 100 fs pulse width and 80 MHz repetition rate. We took two processing parameters into consideration such as laser power, laser exposure time which is related to the stage speed. Therefore, we were able to find the laser optimum conditions for ablation of biological tissues. The mutant and wildtype (control) obtained from laser cutting with a size of 500 µm × 500 µm were directly transferred (in-situ with laser cutting) into a microfabricated chamber containing ~500 nanoliters deionized water for measuring ion conductivity. The ion conductivity is a signature of cell-death mechanisms caused by various stresses. A light with intensity of 100 µmol was exposed to the samples for 2 hours and 20 minutes as a source of stress. A quantitative electrical analysis with high accuracy was assured by utilizing a microchamber, which enables a measurement in nanoliter volume. We measured the impedance which is reciprocal of conductivity using a lock-in amplifier and a precise current source at frequency of 130 Hz. Initially high impedance of mutant sample tended to drop within 2 hours and finally approached the constant value which signified that the cell death mechanism was complete. However, the wildtype sample demonstrated approximately constant impedance (conductivity) during the experiment.
Exploratory Analysis of Social E-health Behavior
Extant literature has documented well that people seek health information via the internet as patients and consumers. Much less, however, is known about interaction and creation behaviors in the development of new online health information and knowledge. More specifically, generalizable sociodemographic data on who engages in this online health behavior via social media is lacking in the sociological literature. The term “social e-health” is introduced to emphasize the difference between seeking behaviors and interaction and creation behaviors. A 2010 dataset of a large nationally representative and randomly sampled telephone survey made freely available from the Pew Research Center is used to examine social e-health behavior according to respondents’ sociodemographics. The dependent variable of social e-health behavior is measured by 13 survey questions from the survey. Gender, race, ethnicity, age, education, and income are used as independent variables. Logistic regression analysis was used to determine the odds of engagement in social e-health behavior based on the sociodemographic predictors. The social determinants of health and digital divide frameworks are used to help explain why socioeconomic variances exist in social e-health behavior. The findings of the current study suggest that predictable sociodemographic patterns along the dimensions of gender, race, age, education, and income exist for those who report engaging in social e-health behavior. This study is important because it underscores the fact that engagement in social e-health behavior is differentially distributed in the general U.S. population according to patterned sociodemographics.
Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View
Faced with the challenges to addressing the novelties of the changing business environments (e.g., new customer requirement, changes in customers taste and preferences, the introduction of new products or services by competitors), organizations seek to build collaboration among their employees who possess complementary knowledge. Integrating complementary knowledge enhances employees' ability to address environmental challenges and foster innovation. Despite the importance of knowledge integration for innovation, integration of such knowledge becomes difficult when employees lack a shared understanding of knowledge, and when the knowledge is newly generated. Because new knowledge is tacit in nature and highly personal to a particular individual, it is difficult to articulate, making knowledge integration (KI) an arduous task. Lack of shared understanding, the presence of new knowledge, and lack of common interests in employees creates three types of knowledge boundaries – syntactic (information processing) boundaries, semantic (interpretive) boundaries, and pragmatic (political) boundaries. The presence of knowledge boundaries makes it difficult for employees to share and access their knowledge with each other. To overcome the challenges related to the knowledge boundaries, employees use boundary-spanning objects, which are common lexicons, common meaning, and common interests, to share and access their knowledge across the boundaries. Although prior studies have emphasized the importance of knowledge integration of various knowledge sources for innovations, examinations of what enhances KI capability of employees for organizational innovation remain limited. In addition, apart from Carlile, (2004) and Franco (2013), which are both case studies, other studies that examine the role of boundary spanning objects for knowledge integration are missing. The knowledge management literature also fails to measures (the success of common lexicons, common meaning, and common interests for achieving KI capability) boundary spanning objects. Therefore, in this study, new measurement items of boundary spanning objects and novelty are developed to test the hypotheses. A survey-based ...
Joint Schemes for Physical Layer Security and Error Correction
The major challenges facing resource constraint wireless devices are error resilience, security and speed. Three joint schemes are presented in this research which could be broadly divided into error correction based and cipher based. The error correction based ciphers take advantage of the properties of LDPC codes and Nordstrom Robinson code. A cipher-based cryptosystem is also presented in this research. The complexity of this scheme is reduced compared to conventional schemes. The securities of the ciphers are analyzed against known-plaintext and chosen-plaintext attacks and are found to be secure. Randomization test was also conducted on these schemes and the results are presented. For the proof of concept, the schemes were implemented in software and hardware and these shows a reduction in hardware usage compared to conventional schemes. As a result, joint schemes for error correction and security provide security to the physical layer of wireless communication systems, a layer in the protocol stack where currently little or no security is implemented. In this physical layer security approach, the properties of powerful error correcting codes are exploited to deliver reliability to the intended parties, high security against eavesdroppers and efficiency in communication system. The notion of a highly secure and reliable physical layer has the potential to significantly change how communication system designers and users think of the physical layer since the error control codes employed in this work will have the dual roles of both reliability and security.
The Relationship Between Supplemental Instruction Leader Learning Style and Study Session Design
The purpose of this qualitative study was to examine the learning styles of supplemental instruction leaders at a large, public university during the fall 2010 semester and determine whether or not their personal learning styles influenced the way they designed and developed out-of-class study sessions. The total population of supplemental instruction leaders was 37, of which 24 were eligible to participate in the study. Of the 24 eligible supplemental instruction leaders, 20 completed the entire study. Participants in the study included nine male and 11 female supplemental instruction leaders with a median age of 22.25 years-old. Seventeen participants indicated their classification as senior, two as junior, and one as sophomore. Of the participants, 16 indicated white as a race or ethnicity, one indicated Asian, two indicated African American, and one indicated both American Indian/Alaska Native and white. Supplemental instruction leader learning style was assessed using the Kolb Learning Style Inventory. Leaders were then interviewed, and their study sessions were analyzed. Through triangulation of data from learning style, interviews and actual study session documents, four major themes emerged. The four themes were: 1) incorporation of personal experience into study session design, 2) the sense of impact on student learning, 3) a feeling of the need to incorporate varied activities into study session design, and 4) the concept that students must take ownership over their own learning. No consistent pattern emerged among the themes; however, the results attributed out-of-class study session design to both the incorporation of personal learning style preferences as identified through the Kolb Learning Style Inventory and training conducted by the institution. Implications for future research include the need for continued research addressing how and if supplemental instruction leader learning style influences out-of-class study session design. Also, as institutions of higher education seek to expand academic support services to ...
Integrating Selective Herbicide and Native Plant Restoration to Control Alternanthera philoxeroides (Alligator Weed)
Exotic invasive aquatic weeds such as alligator weed (Alternanthera philoxeroides) threaten native ecosystems by interfering with native plant communities, disrupting hydrology, and diminishing water quality. Development of new tools to combat invaders is important for the well being of these sensitive areas. Integrated pest management offers managers an approach that combines multiple control methods for better control than any one method used exclusively. In a greenhouse and field study, we tested the effects of selective herbicide application frequency, native competitor plant introduction, and their integration on alligator weed. In the greenhouse study, alligator weed shoot, root, and total biomass were reduced with one herbicide application, and further reduced with two. Alligator weed cumulative stem length and shoot/root ratio was only reduced after two applications. In the greenhouse, introduction of competitors did not affect alligator weed biomass, but did affect shoot/root ratio. The interaction of competitor introduction and herbicide did not significantly influence alligator weed growth in the greenhouse study. In the field, alligator weed cover was reduced after one herbicide application, but not significantly more after a second. Introduction of competitor species had no effect on alligator weed cover, nor did the interaction of competitor species and herbicide application. This study demonstrates that triclopyr amine herbicide can reduce alligator weed biomass and cover, and that two applications are more effective than one. To integrate selective herbicides and native plant introduction successfully for alligator weed control, more research is needed on the influence competition can potentially have on alligator weed growth, and the timing of herbicide application and subsequent introduction of plants.
A Comparative Analysis of Haydn's Horn Concerto and Trumpet Concerto
Among the existing solo instrumental concertos of Joseph Haydn's oeuvre are two concertos for brass instruments. These are the Horn Concerto in D Major (Hob. VIId: 3) and Trumpet Concerto in E-flat Major (Hob. VIIe: 1). In addition to their standing as the only two concertos for solo brass instruments written by Haydn in existence, the two concertos provide a unique opportunity for insight into the history of the concerto genre and Haydn's change in compositional style. This is because of their chronological position within Haydn's oeuvre; the Horn Concerto was composed in 1762 during the early years of Haydn's employment with the Esterházy family and the Trumpet Concerto in 1796 as the last known concerto written by Haydn. Significant changes had occurred during that thirty four year time-span, not only in Haydn's life, but also within the field of music. This dissertation examines some of these changes and provides a comparative analysis of these two pieces. More specifically, it employs Schenkerian analysis of the voice-leading and structure of both concertos to examine the transformation in Haydn's compositional style and show the evolution of concerto form. This evolution in style between the Horn Concerto and Trumpet Concerto is most prominently marked by a loosening of compositional constraints, including freer formal procedures, instrumentation, harmonic structures, and an increase in chromaticism (aided by the new chromatic abilities of the trumpet). This document provides an in-depth comparative analysis within an often overlooked genre of music and gives insight into changes in Haydn's compositional style and the concerto genre.
Dynamic Measurement of Intraoral Pressure and Sound Pressure With Laryngoscopic Characterization During Oboe Performance
Measurements of intraoral pressure (IOP) and sound pressure level (SPL) were taken of four oboists as they performed two sets of musical exercises: (1) crescendo-decrescendo from pp to ff and back to pp on the pitches D4, G4, C5 and A5, and (2) straight and vibrato performances of the same four pitches at mf. Video images of the vocal tract were also made using flexible fiberoptic nasoendoscopy (FFN). IOP and SPL data were captured in real time by the WinDaq®/Lite software package, with the dB meter located 8-9 inches in directly front of the oboe bell. The study yielded minimum and maximum values from 21.04 to 57.81 mm Hg and from 65.53 to 100.89 dB across all pitches examined. Discussion is included for the following topics: (1) the oboe’s sound envelope, or functional range of IOP and SPL values at different pitch levels, including the nonlinearity in the relationship between IOP and SPL on the oboe, (2) the static activation and kinetic maintenance thresholds for reed vibration, (3) the effect of vibrato on IOP/SPL, (4) the utilization of the vocal tract during execution of dynamic changes and vibrato, and (5) the impact of player experience on control of physical variables.
Qos Aware Service Oriented Architecture
Service-oriented architecture enables web services to operate in a loosely-coupled setting and provides an environment for dynamic discovery and use of services over a network using standards such as WSDL, SOAP, and UDDI. Web service has both functional and non-functional characteristics. This thesis work proposes to add QoS descriptions (non-functional properties) to WSDL and compose various services to form a business process. This composition of web services also considers QoS properties along with functional properties and the composed services can again be published as a new Web Service and can be part of any other composition using Composed WSDL.
Determining the Emissivity of Roofing Samples: Asphalt, Ceramic and Coated Cedar
The goal is to perform heat measurements examine of selected roofing material samples. Those roofing materials are asphalt shingles, ceramics, and cedar. It’s important to understand the concept of heat transfer, which consists of conduction, convection, and radiation. Research work was reviewed on different infrared devices to see which one would be suitable for conducting my experiment. In this experiment, the main focus was on a specific property of radiation. That property is the emissivity, which is the amount of heat a material is able to radiate compared to a blackbody. An infrared measuring device, such as the infrared camera was used to determine the emissivity of each sample by using a measurement formula consisting of certain equations. These equations account for the emissivity, transmittance of heat through the atmosphere and temperatures of the samples, atmosphere and background. The experiment verifies how reasonable the data is compared to values in the emissivity table. A blackbody method such as electrical black tape was applied to help generate the correct data. With this data obtained, the emissivity was examined to understand what factors and parameters affect this property of the materials. This experiment was conducted using a suitable heat source to heat up the material samples to high temperature. The measurements were taken during the experiment and displayed by the IR camera. The IR images show the behavior of surface temperatures being distributed throughout the different materials. The main challenge was to determine the most accurate emissivity values for all material samples. The results obtained by the IR camera were displayed in figures and tables at different distances, which was between the heap lamp and materials. The materials exhibited different behaviors in temperature and emissivity at certain distances. The emissivity of each material varied with different temperatures. The results led to suggestions ...
Identification and Characterization of an Arabidopsis Thaliana Mutant with Tolerance to N-lauroylethanolamime
N-Acylethanolamines (NAEs) are fatty acid derivatives in plants that negatively influence seedling growth. N-Lauroylethanolamine (NAE 12:0), one type of NAE, inhibits root length, increases radial swelling of root tips and reduces root hair numbers in a dose dependent manner in Arabidopis thaliana L. (ecotype Columbia). A forward genetics approach was employed by screening a population of T-DNA “activation-tagged” developed by the Salk Institute lines for NAE resistance to identify potential genes involved in NAE signaling events in Arabidopsis thaliana L. (ecotype Columbia). Seeds of the activation tagged lines were grown at 0, 25, 30, 50, 75 and 100 µM N-lauroylethanolamime (NAE 12:0). Ten plants which displayed NAE tolerance (NRA) seedling phenotypes, compared with wildtype (Columbia, Col-0) seedlings were identified. I focused on one mutant line, identified as NRA 25, where the tolerance to NAE 12:0 appears to be mediated by a single dominant, nuclear gene. Thermal asymmetric interlaced (TAIL) PCR identified the location of the T-DNA insert as 3.86 kbp upstream of the locus At1g68510. Quantitative PCR indicated that the transcript level corresponding to At1g68510 is upregulated approximately 20 fold in the mutant relative to wildtype. To determine whether the NAE tolerance in NRA 25 is associated with overexpression of At1g68510 I created overexpressing lines of At1g68510 with and without GFP fusions behind the 2X35S CaMV promoter. As predicted, results with overexpressing lines of At1g68510 also exhibited enhanced resistance to NAE when compared with the wildtype. Confocal images of the fusion proteins suggest that GFP-At1g68510 is concentrated in the nucleus and this was confirmed by counterstaining with 4', 6-Diamidino-2-phenylindol (DAPI). Futhermore, At1g68510 overexpressing lines and NRA 25 line also exhibited tolerance to abscisic acid (ABA) during seedling germination. The findings suggests that At1g68510 overexpression mediates seedling tolerance to both ABA and NAE, a mechanism independent of fatty acid amide hydrolase ...
Knowledge Based System and Decision Making Methodologies in Materials Selection for Aircraft Cabin Metallic Structures
Materials selection processes have been the most important aspects in product design and development. Knowledge-based system (KBS) and some of the methodologies used in the materials selection for the design of aircraft cabin metallic structures are discussed. Overall aircraft weight reduction means substantially less fuel consumption. Part of the solution to this problem is to find a way to reduce overall weight of metallic structures inside the cabin. Among various methodologies of materials selection using Multi Criterion Decision Making (MCDM) techniques, a few of them are demonstrated with examples and the results are compared with those obtained using Ashby's approach in materials selection. Pre-defined constraint values, mainly mechanical properties, are employed as relevant attributes in the process. Aluminum alloys with high strength-to-weight ratio have been second-to-none in most of the aircraft parts manufacturing. Magnesium alloys that are much lighter in weight as alternatives to the Al-alloys currently in use in the structures are tested using the methodologies and ranked results are compared. Each material attribute considered in the design are categorized as benefit and non-benefit attribute. Using Ashby's approach, material indices that are required to be maximized for an optimum performance are determined, and materials are ranked based on the average of consolidated indices ranking. Ranking results are compared for any disparity among the methodologies.
Proteomic Responses in the Gill of Zebrafish Following Exposure to Ibuprofen and Naproxen
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most abundant environmental pharmaceutical contaminants. In this study, a proteomic analysis was conducted to identify proteins differentially expressed in gill tissue of zebrafish (Danio rerio) after a 14-day exposure to the NSAIDs ibuprofen or naproxen. A total of 104 proteins with altered expression as indicated by 2-dimensional electrophoresis were analyzed by liquid chromatography with ion trap mass spectrometry (MS/MS). A total of 14 proteins fulfilled our requirements for identification which included consistency among replicate gels as well as successful MS/MS ion searches with the MASCOT database. The most prominent feature of the differential protein expression observed after NSAID exposure was an up-regulation of proteins belonging to the globin family which are involved in the transport of oxygen from gills and availability of heme molecules required for synthesis of cyclooxygenase. Differential expression was observed at exposure concentrations as low as 1-10 µg/L indicating that altered gene expression may occur in fish subjected to environmentally realistic levels of NSAID exposure.
Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants
This study looked at effects of organic solvents dimethylsulfoxide, dimethylformamide and acetone at 0.01%, 0.05% and 0.1% concentration on germination and seedling development wetland plants. Even at 0.01% level, all solvents affected some aspect of seed germination or seedling growth. Acetone at 0.01% was least toxic. Root morphological characteristics were most sensitive compared to shoot morphological characteristics. This study also looked at bioconcentration patterns of antimicrobial compounds triclosan, triclocarban and methyl-triclosan in wetland plants exposed to Denton Municipal Waste Water Treatment Plant effluent. Bioconcentration patterns of antimicrobial compounds varied among species within groups as well as within organs of species. The highest triclocarban, triclosan and methyltriclosan concentration were in shoot of N. guadalupensis, root of N. lutea and in shoots of P. nodous respectively.
Presence of Wolbachia, A Potential Biocontrol Agent: Screening for Vertebrate Blood Meal Source and West Nile Virus in Mosquitoes in the North Texas Region
West Nile virus (WNV) is a geographically endemic mosquito-borne flavivirus that has spread across the United States infecting birds, mosquitos, humans, horses and other mammals. The wide spread nature of this virus is due to the ability of the mosquito vector to persist in broad, ecological diverse environments across the United States. In this study, mosquito populations in North Texas region were sampled for detection of Wolbachia, blood meal source, and WNV. The ultimate goal of this study was to examine the potential of a biocontrol agent, Wolbachia sp. that colonizes the hindgut of various insects, including mosquitos, as a natural means to interrupt virus transmission from mosquitos to other hosts, including humans. In Australia, Wolbachia sp. from fruit flies (Drosophila melanogaster) have been successfully used to block transmission of a similar pathogenic virus from mosquitos responsible for transmission of Dengue fever. Here, mosquitoes were collected using CDC style Gravid Traps in Denton, Texas, from October 2012 through September 2014. Collected mosquitoes were identified, sexed, and categorized as to the amount of host blood in their alimentary system using a Zeiss Axio Zoom microscope (Carl Zeiss Microscopy, LLC, Thornwood, NY). Culex quinquefaciatus was the dominant blood engorged species collected. Smaller populations of Culex tarsalis and Aedes albopictus, another known vector for WNV were also collected. Mosquito larva were also collected from the UNT water research field station and reared to adults. Cx. tarsalis was the dominant mosquito taken from this habitat. Samples of Cx. quinquefasciatus, Cx. tarsalis and A. albopictus were analyzed for Wolbachia sp. and to identify host blood in the mosquito alimentary system. Total DNA extraction from the pool of mosquito samples was by both commercially available DNA extraction kits (Qiagen, Valencia, CA) and salt extraction technique. Polymerase chain reaction (PCR) was used to amplify and identify Wolbachia ...
Time Series Data Analysis of Single Subject Experimental Designs Using Bayesian Estimation
This study presents a set of data analysis approaches for single subject designs (SSDs). The primary purpose is to establish a series of statistical models to supplement visual analysis in single subject research using Bayesian estimation. Linear modeling approach has been used to study level and trend changes. I propose an alternate approach that treats the phase change-point between the baseline and intervention conditions as an unknown parameter. Similar to some existing approaches, the models take into account changes in slopes and intercepts in the presence of serial dependency. The Bayesian procedure used to estimate the parameters and analyze the data is described. Researchers use a variety of statistical analysis methods to analyze different single subject research designs. This dissertation presents a series of statistical models to model data from various conditions: the baseline phase, A-B design, A-B-A-B design, multiple baseline design, alternating treatments design, and changing criterion design. The change-point evaluation method can provide additional confirmation of causal effect of the treatment on target behavior. Software codes are provided as supplemental materials in the appendices. The applicability for the analyses is demonstrated using five examples from the SSD literature.
Processing, Structure and Tribological Property Relations of Ternary Zn-Ti-O and Quaternary Zn-Ti-Zr-O Nanocrystalline Coatings
Conventional liquid lubricants are faced with limitations under extreme cyclic operating conditions, such as in applications that require lubrication when changing from atmospheric pressure to ultrahigh vacuum and ambient air to dry nitrogen (e.g., satellite components), and room to elevated (>500°C) temperatures (e.g., aerospace bearings). Alternatively, solid lubricant coatings can be used in conditions where synthetic liquid lubricants and greases are not applicable; however, individual solid lubricant phases usually perform best only for a limited range of operating conditions. Therefore, solid lubricants that can adequately perform over a wider range of environmental conditions are needed, especially during thermal cycling with temperatures exceeding 500°C. One potential material class investigated in this dissertation is lubricious oxides, because unlike other solid lubricant coatings they are typically thermodynamically stable in air and at elevated temperatures. While past studies have been focused on binary metal oxide coatings, such as ZnO, there have been very few ternary oxide and no reported quaternary oxide investigations. The premise behind the addition of the third and fourth refractory metals Ti and Zr is to increase the number of hard and wear resistant phases while maintaining solid lubrication with ZnO. Therefore, the major focus of this dissertation is to investigate the processing-structure-tribological property relations of composite ZnO, TiO2 and ZrO2 phases that form ternary (ZnTi)xOy and quaternary (ZnTiZr)xOy nanocrystalline coatings. The coatings were processed by atomic layer deposition (ALD) using a selective variation of ALD parameters. The growth structure and chemical composition of as-deposited and ex situ annealed ternary and quaternary oxide coatings were studied by combined x-ray diffraction/focused ion beam microscopy/cross-sectional transmission electron microscopy, and x-ray photoelectron spectroscopy/Auger electron spectroscopy, respectively. It was determined that the structure varied from purely nanocrystalline (ternary oxides) to composite amorphous/nanocrystalline (quaternary oxides) depending on ALD parameters and annealing temperatures. In particular, the ZnTiO3 ...
Spatial Mismatch Between Hiv Infection and Access to Hiv Service Facilities in Texas
Since 2004, the number of people living with HIV (PLWH) has steadily increased by about 5% and currently, the number in Texas is about 86,000. Though the National HIV/AIDS Strategic Plan seeks to ensure “unfettered access to quality healthcare”, barriers to access still exist especially among minority populations. This study examines the relationship between HIV infection rates and the geographic location of HIV service centers with a focus on 4 counties: namely, Dallas, Denton, Harris and Tarrant. The goal is to show whether there is a spatial mismatch between HIV rates and service providers. Are service facilities located in zip codes where they are most needed? Using the vulnerability framework and the Inverse Care Law (ICL), we address the research question using demographic variables (race/ethnicity, sex, poverty, education attainment) and HIV data. Our results show that extreme vulnerable zip codes have high HIV rates and closest proximity to HIV service providers.
“No Paper Cowboys”: Stories
Equilibrium is paramount in the crafting of a story, and for every writer this sense of balance is different. The writer must manage a balance of showing and telling, of denotation and connotation, and forever strive to find the perfect word in both the denotative and connotative sense, so that the reader and writer can meeting in a living story—both in the ink on the page and the remaining white space.
Determinants of Effort and Associated Cardiovascular Response to a Behavioral Restraint Challenge
This study directly tested implications of motivation intensity theory on effort to restrain against a behavioral urge or impulse (i.e. restraint intensity). Two factors were manipulated—magnitude of an urge and the importance of successfully resisting it—with cardiovascular (CV) responses related to active coping measured. Male and female undergraduate students were presented with a mildly- or strongly evocative film clip with instructions to refrain from showing any facial response. Success was made more or less important through coordinated manipulations of outcome expectancy, ego-involvement, and performance assessment. As expected, systolic blood pressure responses assessed during the performance period were proportional to the evocativeness of the clip when importance was high, but low regardless of evocativeness when importance was low. These findings support a new conceptual analysis concerned with the determinants and CV correlates of restraint intensity. Implications of the study and associations with current self-regulatory literature are discussed.
Family Structure and Marijuana Use Among Adolescents
Family structure as a predictive variable of juvenile delinquency has been studied for the last hundred years. This relationship originated due to societal belief that divorce was detrimental to adolescents. Due to the changing societal roles in the United States, family structure has been changing. More children are growing up in non-intact families, such as single-parent households, households with stepparents, cohabitating families, and households without a parent present. To study the effect family structure has on juvenile delinquency, researchers have utilized social control theory, differential association, self-control theory and general strain theory to conceptualize variables to explain why family structure influences delinquent behavior. A review of previous literature on this topic indicates that living in intact households, which are households with two biological parents who are married, have, on average, the lowest rates of delinquency. This thesis investigates the relationship between family structure and lifetime marijuana use among eighth and tenth grade adolescents in the United States through the use of secondary data analysis of Monitoring the Future Study, 2012. The results provide support for the relationship between family structure and lifetime marijuana use.
Interpersonal Factors Related to the Pursuit of a Higher Education Among First Generation Undergraduate Students
The typical educational stressors experienced by college students, in conjunction with developmental stressors such as separation from parents, individuation, and perceived social support, can interact to impact adaptation significantly. First generation college students (students who are the first in their family to attend college) can experience stressors beyond the typical educational stressors experienced by later generation college students, including lack of support from family and peers as well as financial difficulties that can interact to impact the pursuit of an education beyond the undergraduate level. The present study examined factors that may be especially influential in the pursuit of a higher education for first generation college students. Results indicated that aspects of family enmeshment were related to academic motivation for first generation students, but not for later generation students. Exploratory analysis showed that family and finances were mentioned more often among first generation students when compared to later generation students as stressors that strongly influence the desire to continue beyond the undergraduate level.
Expertise Revisited: Reflecting on the Intersection of Science and Democracy in the Case of Fracking
This dissertation aims to explain the conditions under which expertise can undermine democratic decision making. I argue that the root of the conflict between expertise and democracy lies in what I call insufficiently “representative” expertise – that is forms of scientific research that are not relevant to the policy questions at hand and that fail to make visible their hidden values dimensions. I claim that the scholarly literature on the problem of expertise fails to recognize and address the issue correctly, because it does not open the black box of scientific methodologies. I maintain that only by making sense of the methodological choices of experts in the context of policy making can we determine the relevance of research and reveal the hidden socio-political values and consequences. Using the case of natural gas fracking, I demonstrate how expert contributions – even though epistemically sound – can muddle democratic policy processes. I present four case studies from controversies about fracking to show how to contextualize scientific methodologies in the pertinent political process. I argue that the common problem across all case studies is the failure of expertise to sufficiently represent stakeholders’ problems and concerns. In this context, “representation” has three criteria: (1) the operational research questions on which the qualified experts work are relevant to stakeholders’ problems and concerns; (2) the non-epistemic values and consequences of epistemic choices of experts are compatible with social and political values and priorities; and (3) hidden values attached to facts are fully transparent and openly debated. In the conclusion, I propose a normative version of this representation theory that can be used to evaluate the appropriateness of expertise for democratic policy making. Instead of the value-free science ideal, I propose a new ideal to legitimately allow non-epistemic values in scientific reasoning without compromising the soundness of ...
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 sources to generate four hypothetical scenarios. Ozone sensitivity analysis was performed for a future year of 2018 and it was based on the photochemical simulation that TCEQ had developed for demonstrating ozone attainment under the State Implementation Plan (SIP). Results showed various level of ozone impact at different locations within the DFW region attributed to area and point sources of emissions in the shale region. Maximum ozone impact due to shale gas activities is expected to be in the order of several parts per billion, while lower impacts on design values were predicted. The results from the photochemical modeling can ...
Energy Harvesting Wireless Piezoelectric Resonant Force Sensor
The piezoelectric energy harvester has become a new powering option for some low-power electronic devices such as MEMS (Micro Electrical Mechanical System) sensors. Piezoelectric materials can collect the ambient vibrations energy and convert it to electrical energy. This thesis is intended to demonstrate the behavior of a piezoelectric energy harvester system at elevated temperature from room temperature up to 82°C, and compares the system’s performance using different piezoelectric materials. The systems are structured with a Lead Magnesium Niobate-Lead Titanate (PMN-PT) single crystal patch bonded to an aluminum cantilever beam, Lead Indium Niobate-Lead Magnesium Niobate-Lead Titanate (PIN-PMN-PT) single crystal patch bonded to an aluminum cantilever beam and a bimorph cantilever beam which is made of Lead Zirconate Titanate (PZT). The results of this experimental study show the effects of the temperature on the operation frequency and output power of the piezoelectric energy harvesting system. The harvested electrical energy has been stored in storage circuits including a battery. Then, the stored energy has been used to power up the other part of the system, a wireless resonator force sensor, which uses frequency conversion techniques to convert the sensor’s ultrasonic signal to a microwave signal in order to transmit the signal wirelessly.
General Satisfaction of Students in 100% Online Courses in the Department of Learning Technologies at the University of North Texas
The purpose of this study was to examine whether there are significant relationships between the general satisfaction of students and learner-content interaction, learner-instructor interaction, learner-learner interaction, and learner-technology interaction in 100% online courses. There were 310 responses from the students. This study did not use data from duplicate students and instructors. Excel was used to find duplicate students and instructors; therefore, 128 responses were deleted. After examination of box plots, an additional four cases were removed because they were outliers on seven or more variables. Nineteen responses were deleted because they did not answer all questions of interest, resulting in a total sample of 159 students. Multiple regression analysis was used to examine the relationship between the four independent variables and the dependent variable. In addition to tests for statistical significance, practical significance was evaluated with the multiple R2 , which reported the common variance between independent variables and dependent variable. The two variables of learner-content and learner-instructor interaction play a significant role in predicting online satisfaction. Minimally, the variable learner-technology can predict online satisfaction and is an important construct that must be considered when offering online courses. Results of this study provide help in establishing a valid and reliable survey instrument and in developing an online best learning environment, as well as recommendations for institutions offering online learning or considering the development of online learning courses.
Low Leakage Asymmetric Stacked Sram Cell
Memory is an important part of any digital processing system. On-chip SRAM can be found in various levels of the memory hierarchy in a processor and occupies a considerable area of the chip. Leakage is one of the challenges which shrinking of technology has introduced and the leakage of SRAM constitutes a substantial part of the total leakage power of the chip due to its large area and the fact that many of the cells are idle without any access. In this thesis, we introduce asymmetric SRAM cells using stacked transistors which reduce the leakage up to 26% while increasing the delay of the cell by only 1.2% while reducing the read noise margin of the cell by only 15.7%. We also investigate an asymmetric cell configuration in which increases the delay by 33% while reduces the leakage up to 30% and reducing the read noise margin by only 1.2% compared to a regular SRAM cell.
Space in Space: Privacy Needs for Long-Duration Spaceflight
Space exploration is a uniquely human activity. As humans continue to push the limits of exploring the unknown, they have sought knowledge supporting the sustenance of life in outer space. New technologies, advancements in medicine, and rethinking what it means to be a “community” will need to emerge to support life among the stars. Crews traveling beyond the Moon will rely on the development of new technologies to support the technological aspects of their missions as well as their quality of life while away from Earth. Likewise, through advancements in medicine, scientists will need to address remaining questions regarding the effects of long-duration spaceflight on the human body and crew performance. Space explorers must learn to utilize these new technologies and medical advancements while learning to adapt to their new environment in space and as a space community. It is important that researchers address these issues so that human survival beyond Earth is not only achievable but so that life among the stars is worth living and sustaining. This thesis addressed these issues in an attempt to extend the trajectory of space exploration to new horizons.
The Effects of Adlerian Play Therapy on Maladaptive Perfectionism and Anxiety and in Children
I used singlecase A-B-A experimental design to examine the effectiveness of Adlerian play therapy (AdPT) for children identified with clinical levels of perfectionism on the Conners Parent Rating Scale-Revised and Conners Teacher Rating Scale-Revised. Participants were 2 children, a 10 year-old Hispanic male and a 7 year-old Caucasian female. To examine the effect of AdPT on maladaptive perfectionism and anxiety, the Child-Adolescent Perfectionism Scale and the Revised Children’s Manifest Anxiety Scale were administered to the children twice weekly over 3 phases of the study: baseline (6 administrations), intervention (12-16 administrations), and maintenance (6 administrations) for a total of 24 to 29 data points. Additionally, parents and teachers completed the Conners Rating Scales-Revised5 times: (1) prior to study, (2) following baseline/prior to treatment, (3) midpoint of treatment, (4) following treatment, and (5) following maintenance phase.During the intervention phase, the male and female participants attended 21 and 16 play therapy sessions, their mothers attended 6 and 5 parent consultations, and their teachers attended 6 and 3 teacher consultations, respectively. Analysis of the child self-report assessments indicated mixed and inconclusive results regarding the effects of AdPT on target behaviors. However, results of the parent and teacher reports indicated clinically significant reductionsin maladaptive perfectionism and anxiety over the five points of measurement for both participants. The participants’ maladaptive perfectionism moved from the clinical to the normal range. Implications for practice and future research are indicated.
Photoactivatable Quantum Dots in Super-Resolution Microscopy of Muscle
Super-resolution 3D imaging was achieved using newly synthesized photoactivatable quantum dot (PAQ dot) probes. Quantum dots were modified with a novel quencher system to make them photoactivatable. The unique properties of these PAQ dots enable single-fluorophore localization in three dimensions using a confocal microscopy optical sectioning method. Myosin and tropomyosin of rabbit myofibrilar bundles were specifically labeled with the newly synthesized PAQ dot. A sufficient number of single quantum dots were photoactivated, localized and reduced to their centroid and then reconstructed to a super-resolution image. The acquired super-resolution image shows a lateral and an axial sub-diffraction resolution and demonstrates ultrafine striations with widths less than 70 nm that are not evident by conventional confocal microscopy. The striations appear to be related to nebulin thin filament binding protein. This newly developed imaging system is cutting edge for its high resolution and localization as well its simplicity and convenience.
Determination of the Optimal Number of Strata for Bias Reduction in Propensity Score Matching.
Previous research implementing stratification on the propensity score has generally relied on using five strata, based on prior theoretical groundwork and minimal empirical evidence as to the suitability of quintiles to adequately reduce bias in all cases and across all sample sizes. This study investigates bias reduction across varying number of strata and sample sizes via a large-scale simulation to determine the adequacy of quintiles for bias reduction under all conditions. Sample sizes ranged from 100 to 50,000 and strata from 3 to 20. Both the percentage of bias reduction and the standardized selection bias were examined. The results show that while the particular covariates in the simulation met certain criteria with five strata that greater bias reduction could be achieved by increasing the number of strata, especially with larger sample sizes. Simulation code written in R is included.
Determination of Molecular Descriptors for Illegal Drugs by Gc-fid Using Abraham Solvation Model
The Abraham solvation parameter model is a good approach for analyzing and predicting biological activities and partitioning coefficients. The general solvation equation has been used to predict the solute property (SP) behavior of drug compounds between biological barriers. Gas chromatography (GC) retention time can be used to predict molecular descriptors, such as E, S, A, B & L for existing and newly developed drug compounds. In this research, six columns of different stationary phases were used to predict the Abraham molecular descriptors more accurately. The six stationary phases used were 5% phenylmethyl polysiloxane, 6% cyanopropylphenyl 94% dimethylpolysiloxane, 5% diphenyl 95% dimethylpolysiloxane, 100% dimethylpolysiloxane, polyethylene glycol and 35% diphenyl 65% dimethylpolysiloxane. Retention times (RT) of 75 compounds have been measured and logarithm of experimental average retention time Ln(RTexp) are calculated. The Abraham solvation model is then applied to predict the process coefficients of these compounds using the literature values of the molecular descriptors (Acree Compilation descriptors). Six correlation equations are built up as a training set for each of the six columns. The six equations are then used to predict the molecular descriptors of the illegal drugs as a test set. This work shows the ability to extract molecular information from a new compound by utilizing commonly used GC columns available with the desired stationary phases. One can simply run the new compound in GC using these columns to get the retention time. Plugging in the retention time into the developed equations for each of the column will predict the molecular descriptors for the test compound and will give some information about the properties of the compound.
Routine Leisure Activities and Adolescent Marijuana Use: Moderating Effects of Family Structure
How adolescents spend their time is a crucial predictor of their engagement in delinquency. Activities with peers away from direct supervision of adults are of concern as more opportunities and motivation to use marijuana exist in such situations. However, adolescents may vary in their propensity to use marijuana when faced the opportunity. Especially adolescents living with a single parent may have a higher propensity compared to those from two-parent households to use marijuana due to reduced parental monitoring and increased peer attachment. This thesis investigates the moderating effects of family structure on the routine leisure activities and adolescent marijuana use relationship, using data from Monitoring the Future Study 2007, 12th Grade Survey. The results provide partial support for the moderating effects.
Real Analyticity of Hausdorff Dimension of Disconnected Julia Sets of Cubic Parabolic Polynomials
Consider a family of cubic parabolic polynomials given by for non-zero complex parameters such that for each the polynomial is a parabolic polynomial, that is, the polynomial has a parabolic fixed point and the Julia set of , denoted by , does not contain any critical points of . We also assumed that for each , one finite critical point of the polynomial escapes to the super-attracting fixed point infinity. So, the Julia sets are disconnected. The concern about the family is that the members of this family are generally not even bi-Lipschitz conjugate on their Julia sets. We have proved that the parameter set is open and contains a deleted neighborhood of the origin 0. Our main result is that the Hausdorff dimension function defined by is real analytic. To prove this we have constructed a holomorphic family of holomorphic parabolic graph directed Markov systems whose limit sets coincide with the Julia sets of polynomials up to a countable set, and hence have the same Hausdorff dimension. Then we associate to this holomorphic family of holomorphic parabolic graph directed Markov systems an analytic family, call it , of conformal graph directed Markov systems with infinite number of edges in order to reduce the problem of real analyticity of Hausdorff dimension for the given family of polynomials to prove the corresponding statement for the family .
Consensus Building in Sensor Networks and Long Term Planning for the National Airspace System
In this thesis, I present my study on the impact of multi-group network structure on the performance of consensus building strategies, and the preliminary mathematical formulation of the problem on improving the performance of the National Airspace system (NAS) through long-term investment. The first part of the thesis is concerned with a structural approach to the consensus building problem in multi-group distributed sensor networks (DSNs) that can be represented by bipartite graph. Direct inference of the convergence behavior of consensus strategies from multi-group DSN structure is one of the contributions of this thesis. The insights gained from the analysis facilitate the design and development of DSNs that meet specific performance criteria. The other part of the thesis is concerned with long-term planning and development of the NAS at a network level, by formulating the planning problem as a resource allocation problem for a flow network. The network-level model viewpoint on NAS planning and development will give insight to the structure of future NAS and will allow evaluation of various paradigms for the planning problem.
Evaluating Appropriateness of Emg and Flex Sensors for Classifying Hand Gestures
Hand and arm gestures are a great way of communication when you don't want to be heard, quieter and often more reliable than whispering into a radio mike. In recent years hand gesture identification became a major active area of research due its use in various applications. The objective of my work is to develop an integrated sensor system, which will enable tactical squads and SWAT teams to communicate when there is absence of a Line of Sight or in the presence of any obstacles. The gesture set involved in this work is the standardized hand signals for close range engagement operations used by military and SWAT teams. The gesture sets involved in this work are broadly divided into finger movements and arm movements. The core components of the integrated sensor system are: Surface EMG sensors, Flex sensors and accelerometers. Surface EMG is the electrical activity produced by muscle contractions and measured by sensors directly attached to the skin. Bend Sensors use a piezo resistive material to detect the bend. The sensor output is determined by both the angle between the ends of the sensor as well as the flex radius. Accelerometers sense the dynamic acceleration and inclination in 3 directions simultaneously. EMG sensors are placed on the upper and lower forearm and assist in the classification of the finger and wrist movements. Bend sensors are mounted on a glove that is worn on the hand. The sensors are located over the first knuckle of each figure and can determine if the finger is bent or not. An accelerometer is attached to the glove at the base of the wrist and determines the speed and direction of the arm movement. Classification algorithm SVM is used to classify the gestures.
The Effect of It Process Support, Process Visualization and Process Characteristics on Process Outcomes
Business process re-engineering (part of the Business Process Management domain) is among the top three concerns of Information Technology (IT) leaders and is deemed to be one of many important IT leveraging opportunities. Two major challenges have been identified in relation to BPM and the use of IT. The first challenge is related to involving business process participants in process improvement initiatives using BPM systems. BPM technologies are considered to be primarily targeted for developers and not BPM users, and the need to engage process participants into process improvement initiatives is not addressed, contributing to the business-IT gap. The second challenge is related to potential de-skilling of knowledge workers when knowledge-intensive processes are automated and process knowledge resides in IT, rather than human process participants. The two identified challenges are not separate issues. Process participants need to be knowledgeable about the process in order to actively contribute to BPM initiatives, and the loss of process knowledge as a result of passive use of automated systems may further threaten their participation in process improvement. In response to the call for more research on the individual impacts of business process initiatives, the purpose of this dissertation study is to understand the relationship between IT configurations (particularly process support and process visualization), process characteristics and individual level process outcomes, such as task performance and process knowledge. In the development of the research model we rely on organizational knowledge creation literature and scaffolding in Vygotsky’s Zone of Proximal Development, business process modeling and workflow automation research, as well as research on the influence of IT on individual performance. The theoretical model is tested empirically in experimental settings using a series of two studies. In both studies participants were asked to complete tasks as part of a business process using different versions of a mock-up ...
Interrelated Histories, Practices, and Forms of Communication: Using Arabic Calligraphy to Learn Arabic Typography
In this self-study inquiry, I studied my graphic design practice in a professional setting, focusing on my Arabic typographic skills and knowledge. My roles as researcher and design educator indivisibly intertwined throughout this research. I worked to understand the value of calligraphy in art and design education, highlighting its power as an art form while also emphasizing its pedagogical potentials. I utilized two theoretical approaches suited to investigating and understanding the Arabic letters as text and image, Ibn Arabi’s science of letters, or 'ilm al-hurûf, and semiotics. I applied my theoretical framework to three distinctive artworks to investigate their uses of the Arabic letters, contemplating their roles in modern and contemporary Arab art. Essential to my research was learning Arabic calligraphy through two approaches: 1) I attended a calligraphy workshop, and 2) I conducted three self-study experimentations. I analyzed my experience through visual representations, commentary, and narrative inquiry to assess Arabic calligraphy’s significance for graphic design education. As such, my experimentations confirmed Arabic calligraphy’s aesthetic and educational value. I employed my findings to create a contemporary Arabic typography curriculum suitable for university-level students. This curriculum is built on learning theories such as visual culture analysis, semiotics, constructivist theory, play principles, and critical thinking, aiming to situate Arabic calligraphy as a modern learning model significant for typography education. Finally, I constructed a basic course for Arabic typography to support students’ development of Arabic typography fluency.
Therapist (Dis)continuity, Therapeutic Relationship, and (Premature) Termination in a Psychology Training Clinic
Premature termination is a substantial problem with significant adverse effects for clients, therapists, and treatment organizations. Unfortunately, it is also a relatively common phenomenon within mental healthcare settings. Across varied mental healthcare settings, rates of premature termination have reportedly ranged from 19.7 % to 40 %. Perhaps not surprisingly, the rate of premature termination in training clinics is substantially higher than in community mental health settings and private practice, with 75 to 80 % of clients ending treatment services prematurely. The purpose of this study was to explore the combined effect of intake therapist continuity or discontinuity, and quality of the therapeutic relationship on premature termination. Intake therapist continuity, measures of working alliance, and termination outcome from 524 clients at the University of North Texas Psychology Clinic were utilized for adults receiving individual therapy services between August 2008 and August 2013. Results of the study suggest intake therapist continuity did not predict subjective termination status (X2(2, n = 524) = 1.61, p = 0.45), nor did it predict change in symptomology status (X2(3, n = 453) = 1.14, p = 0.77). Additionally, working alliance predicted subjective termination status (X2(6, n = 212) = 21.17, p < 0.01), but not change in symptomology status (X2(9, n = 208) = 6.27, p = 0.71). The findings of the current study are discussed, as well as suggestions for further research related to client, therapist, treatment, and procedural variables and their impact on premature termination.