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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.
Evaluation of Texas Home Instruction for Parents of Preschool Youngsters Program on Reading and Math Achievement for Grades K to 8
This study was intended to evaluate the impact of socioeconomically disadvantaged children's participation in the Texas Home Instruction for Parents of Preschool Youngsters (TX HIPPY) Program on their school readiness and academic achievement. The study used a quasi-experimental design and applied full and optimal propensity score matching (PSM) to address the evaluation concern of the impact of the TX HIPPY program on HIPPY participants' academic achievement compared to non-HIPPY participants. This evaluation targeted former HIPPY participants and tracked them in the Dallas ISD database through Grade Levels K-8. Data were obtained by administering Istation's Indicators of Progress (ISIP) for kindergarten, TerraNova/SUPERA for Grades K-2, and State of Texas Assessments of Academic Readiness for math and reading (STAAR) for Grades 3-8. HIPPY and non-HIPPY groups were matched using propensity score analysis procedures. The evaluation findings show that the TX HIPPY program positively influences kindergarten students to start school ready to learn. The findings of math and reading achievements suggest that HIPPY children scored at the same level or higher than non-HIPPY children did on math and reading achievement, indicating that TX HIPPY program has achieved its goal of helping children maintain long-term academic success. However, the evaluation findings also indicated that the impact evaluation framework must be designed with attention to higher-level factors beyond academic achievement that influence children's academic success.
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.
Two Argentine Song Sets: A Comparison of Songs by De Rogatis and Ginastera
Latin American classical vocal repertoire is vast, but in the United States, we only hear a fairly limited part of this literature. Much of this repertoire blends western European classical music traditions and native folk music traditions. One example of such a Latin American vocal work that is well-known in the United States is Alberto Ginastera's frequently performed song set from 1943, Cinco canciones populares argentinas. However, another lesser-known, earlier work, Cinco canciones argentinas (1923), by fellow Argentine composer Pascual De Rogatis (1880-1980) deserves attention as well. As with Ginastera's set, De Rogatis' songs are based on Argentine folk genres, but contain stylistic features of European classical music of its time. De Rogatis' neglected songs are a significant, overlooked part of Argentine classical music history, and a full understanding of well-known works such as Ginastera's song set and of the genre as a whole, must include attention to De Rogatis' Cinco canciones argentinas. Beyond vocal repertoire, De Rogatis' songs are an important part of the development of Argentine classical music. While Western musical trends change rapidly, folk music remains largely unchanged. Both De Rogatis and Ginastera were proud of their Argentine heritage, and incorporated traditional music into their compositions. I believe that De Rogatis's composition had a direct influence on Ginastera, and that the similarities between the two sets are not coincidental.
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.
Students' Attitudes toward Educational Gamification in Online Learning Environments
This study explored undergraduate and graduate students' attitudes toward the pleasurability of educational gamification in online learning environments. The study is a sequential explanatory mixed-methods research that investigated students' attitudes quantitatively, then qualitatively. In the quantitative phase, an online survey, the Pleasurable Learning Experiences scale (PLLEXs), was administrated at one of the largest public southwestern universities in the U.S. (N = 119). The qualitative phase involved conducting eight semi-structured interviews with selected participants. The PLLEXs uses a 4-point Likert scale that encompasses 4 subscales: (a) Preferences for Instructions, (b) Preferences for Instructors' Teaching Styles, (c) Preferences for Activities, and (d) Preferences for Learning Effectiveness. A series of analyses of variances (ANOVAs) were used to identify predictors of students' overall attitudes toward educational gamification. The main findings were: (a) students had strong preferences toward educational gamification with Preferences of Instructions rated the highest subscale and Preferences for Activities rated the lowest subscale, (b) major was a statistically significant predictor of students' attitudes toward educational gamification, (c) international students had statistically significant lower preferences toward educational gamification compared with U.S. domestic students, (c) online learning experiences measured by the number of previous online courses and the number of hours spent weekly on computers for academic-related work were statistically significant predictors of students' attitudes toward educational gamification, (d) instructor's feedback was the most important aspect and online collaboration was the most challenging aspect in online learning environments, and (e) the use of multimedia in LMSs can support or hinder teaching and learning activities.
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 …
Online Construction of Android Application Test Suites
Mobile applications play an important role in the dissemination of computing and information resources. They are often used in domains such as mobile banking, e-commerce, and health monitoring. Cost-effective testing techniques in these domains are critical. This dissertation contributes novel techniques for automatic construction of mobile application test suites. In particular, this work provides solutions that focus on the prohibitively large number of possible event sequences that must be sampled in GUI-based mobile applications. This work makes three major contributions: (1) an automated GUI testing tool, Autodroid, that implements a novel online approach to automatic construction of Android application test suites (2) probabilistic and combinatorial-based algorithms that systematically sample the input space of Android applications to generate test suites with GUI/context events and (3) empirical studies to evaluate the cost-effectiveness of our techniques on real-world Android applications. Our experiments show that our techniques achieve better code coverage and event coverage compared to random test generation. We demonstrate that our techniques are useful for automatic construction of Android application test suites in the absence of source code and preexisting abstract models of an Application Under Test (AUT). The insights derived from our empirical studies provide guidance to researchers and practitioners involved in the development of automated GUI testing tools for Android applications.
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.
Increasing Exercise in Sedentary Adults Using a Contingency and Technology-Based Management Package to Begin and Sustain New Levels of Activity
Using a multiple baseline across participants with a changing criterion, this study explored and evaluated the effects of the individualized contingency management package (goal-setting, education, etc.) with sedentary typical adults while focusing on the mentoring component and the use of the technology of the exercise tracker to increase and sustain physical exercise to a level that increased health-benefiting physical activity. During initial mentoring meeting prior to the start of baseline, each participant was given a Garmin Viovsmart 3® exercise tracker, educated on the basic components of the device, and connected to the dashboard through the Garmin Connect™ app on their smartphones. Once each participant's activity stabilized, participant began intervention with weekly mentoring meetings focused on immediate feedback (social reinforcement), goal-setting and education. Through the Connect™ app, experimenter gave social reinforcement on a VR3 schedule to each participant, and participants were encouraged to participate by commenting to other participants through a private group set up for this study. The results indicate that the individualized contingency management package was effective for three of four participants whom increased their total activity minutes from pre-intervention range 0-104 min of weekly activity to post-intervention range of 269-404 min weekly. The two participants that completed two- and six-week maintenance checks continued to increase their total weekly activity minutes. Each of the participants showed increases in exercise during baseline that might suggest the wearable itself, along with basic instruction may be responsible for the increase in activity levels. To our knowledge, this is the first study to isolate an exercise tracker. The exercise tracker created social validity and meaningful change as it allowed participants to choose preferred exercises and plan their own exercise schedules. This helped facilitate natural generalization to their environment. Future research in behavioral health paired with technology will be far-reaching now that real-time assessments …
The Effects of Contingency Type on Accuracy and Reaction Time
Positive and negative reinforcement contingencies have been compared in terms of preference, but the differential effects of positive and negative reinforcement on reaction time and accuracy with other variables controlled remain unclear. Fifteen undergraduate students participated in a sound discrimination task that involved random mixed-trial presentations of positive and negative reinforcement contingencies. The participants' goal was to correctly identify whether the tone was shorter or longer than 600 milliseconds. On positive reinforcement trials, the participants received feedback and money tallies only if they identified the sound length correctly, with each correct response in the positive reinforcement trials earning the participant 10 cents. On negative reinforcement trials, the participants received feedback and money tallies only if they identified the sound length incorrectly, with incorrect trials subtracting 10 cents from the participants' total money (which began at $4.00 to equalize the weights of the positive and negative reinforcement contingencies). Accuracy analyses showed a relatively curvilinear relationship between the number of errors for each participant and the binned duration of the sound stimulus, with no differences across the positive and negative reinforcement conditions. Results also indicated weak linear negative correlations at the single subject level between comparison stimulus duration and reaction time, with similar slopes between positive and negative reinforcement trials, and strong curvilinear correlations at the group level, indicating differences between grouped and individual analyses. Overall our results appear to support abandoning the distinction between positive and negative reinforcement as two separate behavioral processes.
A Study of the Impact and Influence of the Recordings and Pedagogy of David Baldwin
David Baldwin has been the trumpet professor at the University of Minnesota since 1974. His most celebrated accomplishment is his recording of the Charlier 36 Etudes de Transcendantes and the Marcel Bitsch Vingt Etudes. In addition to this recording Baldwin has made recordings of etude books by Small, St. Jacome, Arban, Caffarelli, Smith, and the 32 Etudes de Perfectionnement also by Charlier. The quality of performance on all of these makes them excellent reference recordings. The back cover of the Etudes 32 de Perfectionnement reveals that the two-CD album, with a total run time of 115:35, was recorded over a span of four days. Endurance is a topic that all brass players confront. Baldwin wrote an etude book titled Lips of Steel that also contains two previously published articles on the topic of endurance. His ideas on endurance reveal a unique approach. This study analyzes the pedagogical concepts in those articles and in Lips of Steel. In addition to his recording projects, Baldwin has had many successful students. Thomas Rolfs and Lynn Erickson are both members of full-time professional orchestras. Larry Griffin, Scott Hagarty, and many others built their careers as professors of trumpet. An investigation of Baldwin's influence on his students further reveals how he approaches teaching and how his pedagogy has influenced his students who are now successful college professors.
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 …
Electrically Tunable Absorption and Perfect Absorption Using Aluminum-Doped Zinc Oxide and Graphene Sandwiched in Oxides
Understanding the fundamental physics in light absorption and perfect light absorption is vital for device applications in detector, sensor, solar energy harvesting and imaging. In this research study, a large area fabrication of Al-doped ZnO/Al2O3/graphene/Al2O3/gold/silicon device was enabled by a spin-processable hydrophilic mono-layer graphene oxide. In contrast to the optical properties of noble metals, which cannot be tuned or changed, the permittivity of transparent metal oxides, such as Al-doped ZnO and indium tin oxide, are tunable. Their optical properties can be adjusted via doping or tuned electrically through carrier accumulation and depletion, providing great advantages for designing tunable photonic devices or realizing perfect absorption. A significant shift of Raman frequency up to 360 cm-1 was observed from graphene in the fabricated device reported in this work. The absorption from the device was tunable with a negative voltage applied on the Al-doped ZnO side. The generated absorption change was sustainable when the voltage was off and erasable when a positive voltage was applied. The reflection change was explained by the Fermi level change in graphene. The sustainability of tuned optical property in graphene can lead to a design of device with less power consumption.
Identification and Characterization of an Arabidopsis thaliana Mutant with Tolerance to N-lauroylethanolamine
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.
Information Content of Non-GAAP Earnings of Cross-Listed Companies
To supplement earnings reported under generally accepted accounting principles (GAAP), public companies often voluntarily report alternative measures of earnings called non-GAAP earnings (NGE). These companies assert that NGE exclude the effect of non-recurring transactions, thereby helping users of financial information to better assess the company's past performance and prospects. Because NGE measures are not well defined, managers can exploit the inherent discretion in calculating NGE to mislead users. Prior studies provide arguments and evidence on the informative as well as opportunistic use of NGE. However, the studies have examined the characteristics and informativeness of NGE with a focus on U.S. companies. The results of studies that consider the NGE disclosure by U.S. companies may not be generalizable to the cross-listed companies because foreign financial reporting standards are different from the U.S. GAAP. Further, prior studies report a difference in earnings quality of U.S. firms and cross-listed firms, which can also result in a difference in the informativeness of their NGE. To fill this gap in literature, I examine whether the informativeness of NGE of cross-listed companies is different from that of U.S. companies. This study contributes to the debate on the informativeness of NGE. It provides evidence that in general, NGE are equally informative for U.S. and foreign companies but foreign companies are more opportunistic in excluding recurring items from NGE. The results of this study are of potential interest to investors, regulators, and academics who are interested in and interact with cross-listed companies.
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 …
The Status and Challenges of Online Distance Education Programs in Post-Secondary Institutions in Ghana
The purpose of this study was to identify the status and challenges of online distance education programs in post-secondary institutions in Ghana. This study was a replication of a similar study conducted in Kenya in 2009, at the University of Nairobi and Kenyatta University. This present study was conducted with an online survey using Google survey assessment. The survey requested responses from six post-secondary institutions in Ghana. Out of a total of 450 projected student responses, 309 responses were received with a 69% participation rate. A total of 14 responses were received for instructors out of a projected 30 resulting in 47% participation rate. And for administrators, 8 responses were received out of a projected 12 resulting in a 67% participation rate. Overall the study revealed that Ghana post-secondary institutions have established and incorporated online distance education into their programs, offering both online and blended courses. Some of these institutions established regional centers across the country and incorporated foreign instructors into their programs. The survey also revealed that students were satisfied with the overall online distance education program in their institutions which included the level of instruction, feedback and evaluation. However, there were still challenges revealed from the study that included the high cost of education, frequent power outages, school stoppages as a result of instructor strikes and the need to restructure courses to include projects.
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.
Practical Evaluation of a Software Defined Cellular Network
This thesis proposes a design of a rapidly deployable cellular network prototype that provides voice and data communications and it is interoperable with legacy devices and the existing network infrastructure. The prototype is based on software defined radio and makes use of IEEE 802.11 unlicensed wireless radio frequency (RF) band for backhaul link and an open source GSM implementation software. The prototype is also evaluated in environments where there is limited control of the radio frequency landscape, and using Voice Over Internet Protocol (VoIP) performance metrics to measure the quality of service. It is observed that in environments where the IEEE 802.11 band is not heavily utilized, a large number of calls are supported with good quality of service. However, when this band is heavily utilized only a few calls can be supported as the quality of service rapidly degrades with increasing number of calls, which is due to interference. It is concluded that in order to achieve tolerable voice quality, unused licensed spectrum is needed for backhaul communication between base stations.
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 …
Instructional Personnel Perceptions on Integrating Instructional Technology in K-12 Classrooms: A Case Study
Integrating digital pedagogy into instruction in a manner that promotes critical thinking and drives increased student achievement and engagement in all classrooms is a goal of many campuses and districts that invest heavily in hardware, software, and professional development on an annual basis. Digital pedagogy goals tend to center around preparing students for the 21st century workforce, promoting instruction that is more engaging, and providing deeper learning for all students; however, achieving these goals is not possible without teachers willing and able to effectively implement instructional technology into the content they are teaching. The conceptual framework consists of digital leadership, teacher engagement, and resources and supports. This case study focused on the district-wide integration of technology into instruction through the elements found in the conceptual framework. Educators, from kindergarten through twelfth grade were surveyed about their attitudes, self-efficacy perceptions and willingness to integrate digital pedagogies into their current teaching practices. The online survey that utilized Likert-like scales to gather demographic information as well educator perceptions on digital integration, teaching philosophy, digital self-efficacy, and leadership's focus and expectations regarding instructional technology. Additional data, from a variety of district documents, was also gathered on leadership, professional development, and infrastructure supports utilized to implement instructional technology.
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.
Trajectories of Burden and Depression in Caregivers Following Traumatic Injury: The Role of Resilience
As part of an effort to understand psychological consequences among family members of patients sustaining a traumatic injury, medical research has turned to the role of resilience – or the ability to bounce back from and maintain psychological well-being in the wake of an adverse event— in mitigating the potential distress (i.e., depression and burden) of caregiving (Bonanno, 2004; Roberson et al., under review). This study sought to examine the ability for trait-resilience to predict trajectories of distress over the course of a year among 124 family members and loved ones of patients admitted to a Level I Trauma Center. A cross-lagged path model examining resilience, burden, and depression at baseline, 3, 6, and 12 months after injury showed that, while depression strongly predicted later burden, resilience was not a significant predictor of either outcome in the model. When depression and burden were subjected to a person-centered analysis (i.e., latent growth curve analysis), two major classes were identified: caregivers with high, chronic distress (33% of the sample) and low-moderate distress that declined over time. A three-class solution for caregiver burden further identified a moderate, increasing trajectory class. Predictive discriminant analyses revealed that trait-resilience was a major differentiating trait between class membership (rs = .23 for depression; rs = .32 for burden); further, presence of PTSD symptoms at baseline, gender, and history of depression were shown to be strong factors in distinguishing class membership across both outcomes. This study helps shed insight into the well-being of caregivers in the wake of a loved one's traumatic injury, in addition to possible identifying risk factors while patients are still admitted in the ICU. Lastly, the study provides alternatives for analyses that focus on longitudinal outcomes, particularly person- vs. variable-centered solutions.
Applications of Metallic Clusters and Nanoparticles via Soft Landing Ion Mobility, from Reduced to Ambient Pressures
Nanoparticles, simple yet groundbreaking objects have led to the discovery of invaluable information due to their physiological, chemical, and physical properties, have become a hot topic in various fields of study including but not limited to chemistry, biology, and physics. In the work presented here, demonstrations of various applications of chemical free nanoparticles are explored, from the determination of a non-invasive method for the study of the exposome via using soft-landing ion mobility (SLIM) deposited nanoparticles as a matrix-assisted laser desorption/ionization (MALDI-MS) matrix replacement, to the direct SLIM-exposure of nanoparticles onto living organisms. While there is plenty of published work in soft-landing at operating pressures of 1 Torr, the work presented here shows how this technology can be operated at the less common ambient pressure. The ease of construction of this instrument allows for various modifications to be performed for a wide array of applications, furthermore the flexibility in metallic sample, operating pressure, and deposition time only open doors to many other future applications. The work presented will also show that our ambient SLIM system is also able to be operated for toxicological studies, as the operation at ambient pressure opens the door to new applications where vacuum conditions are not desired.
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.
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