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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
9861

Effects of Pheromones and Sexual Orientation on Sexual Attraction in Females

Protti, Tracy Anna 03 February 2016 (has links)
<p> This study examined the effect of sweat exposure on sexual attraction in heterosexual and homosexual women. Strictly heterosexual and homosexual female participants were exposed to underarm pads containing sweat. Samples were collected during the Stimulus Preparation Phase from healthy, strictly heterosexual men and women. Women&rsquo;s samples were collected on Day-14 and Day-27 of cycle, and men&rsquo;s from any two days. </p><p> In the Stimulus Exposure Phase, the male sweat and Day-14 female sweat samples were the experimental conditions, and the no male sweat and Day-27 female sweat were the controls. During the exposure phase, sweat samples were hidden and participants completed two computer tasks. First, the key-press task had participants view or skip male and female photographs. Second, the rating-task had participants rate attractiveness of the male and female photographs. The ratings and viewing times were collected then analyzed. </p><p> Heterosexual women showed a strong preference for male photos over female photos only when exposed to male sweat. They also preferred female photos less than homosexual women when exposed to male sweat or Day-14 female sweat. Homosexual women showed a strong preference for female photos over male photos when exposed to male or female Day-14 sweat. </p><p> Homosexual women also preferred female photos more than heterosexual women when exposed to male sweat or Day-14 female sweat. </p><p> The findings of this study suggest that exposure to male sweat may enhance heterosexual women&rsquo;s preference for men and exposure to female sweat from the ovulatory period of the menstrual cycle may inhibit the preference for women of heterosexual women. However, exposure to male sweat and female sweat from the ovulatory period may enhance the preference for women in homosexual women.</p>
9862

Innovation Abandonment| User-Centric vs. Nonuser-Centric Perception of Facebook

Guidry, Donna M. 03 February 2016 (has links)
<p> Facebook is stable and growing in users; however, the social networking site has seen a drop in certain areas of user participation. This study considers the reasons for potential user abandonment of Facebook with a complex analysis into not only the reasons cited by users as to why they abandon Facebook, but also the compilation of those reasons as part of an overall perception formulated about Facebook. Such reasons contribute to the perception of Facebook as user centric or nonuser-centric. The study hypothesizes that through a process of diffusion of innovation, a non-user-centric perception is growing among Facebook&rsquo;s users. Furthermore, the study compounds upon present research on innovation abandonment theory to offer explanation on the correlation between a perception of Facebook as nonuser-centric and Facebook user abandonment. </p><p> <i>Keywords:</i> Facebook, perception, user-centric, nonuser-centric, diffusion of innovation.</p>
9863

Production Optimization Using an In-Situ Steam Generator in a Rejuvenated Heavy Oil Field

Bujarbarua, Vikram 03 February 2016 (has links)
<p> Steam stimulation is by far the most widely used tertiary oil recovery method. Heavy oil finds its most effective way of production in thermal recovery method. Also with technical effectiveness, steam stimulation brings in cost effectiveness. In-situ steam generation and injection is the most important enhancement to the conventional thermal steam injection technique. Blackbird&trade; Energy LLC, has developed and a new generation in-situ steam generator with a view to make an almost unproductive heavy oil reservoir in North East Texas to start producing. </p><p> In this research, a reservoir simulation study has been performed to history match of pure depletion as well as three months of thermal stimulation done on the reservoir. To mimic the reservoir conditions, Schlumberger Eclipse 300 compositional Simulator has been used. Overall this research performs an evaluation of the newly developed in-situ steam generator capabilities. </p><p> The various predictive runs have been made with changing key performance parameters such as location of steam generator and time of application of thermal energy. There has been reported a considerable increase in production of the heavy oil. As a result, in-situ steam injection has been proved to be an effective and environment friendly recovery technique and should be widely considered for replacing conventional steam generators.</p>
9864

Ultra-Low Power RFIC for Space/Medical/Mobile Applications

Yasami, Saeid 03 February 2016 (has links)
<p> State-of-the-arts design, implementation, and optimization of Ultra-Low Power Radio Frequency Integrated Circuits (ULP RFIC) for medical, space, and mobile applications have been proposed. New approximated formulas in modeling of the circuits and systems for CAD development have been suggested which make the computer simulations more accurate. Algorithm optimizations for faster design time and possible automations compared to traditional and manual implementations are also offered that reduce the final release time of the products in a more systematic way. These design methodologies are based on advancements of IC fabrication in scaling to Nano-meter regimes, improvement of powerful software simulation tools especially at high frequencies, and manipulating novel ideas in development phases. Note that these design proposals are not only limited to space, biomedical, and mobile application; as a matter of fact, they can be used in any chip design and development ranging from smart watch to glasses and etc.</p><p> To have a comprehensive understanding of wireless system design and circuit implementation requires years of experiences and research on multi-disciplinary areas ranging from semiconductor at physic level, circuit analysis, software programming for simulation, test and automation purposes, architecture level, high frequency and RF behavior of components and many more. That is why it has been said the RF design is challenging and takes more years to become an expert on these areas. There are still huge shortages for RF and Analog engineers due to the challenges throughout the world both in industry and academia.</p><p> For the circuits presented in this dissertation, frequencies range from ISM band 2.4GHz for mobile application to 10GHz and 24 GHz in microwave applications. The detail analyses for implementations and simulations have been shown to verify the implementations. Optimizations are presented by extensive analysis and iterative simulations. Solutions and tips to simplify design flows are mentioned throughout the dissertation.</p><p> Chapters begin with introductions and motivations; next, detail discussion and investigation are presented in subsequent sections; finally summaries giving at the end of each chapter. At the end of dissertation, the possible future works and research orientation have been proposed.</p>
9865

An Investigation of Struggling Learners' Motivation to Read

Whited, Jennifer E. 03 February 2016 (has links)
<p> This investigation explores the manifestation of motivation as well as the systematic strategies that speech-language pathology graduate students employ to facilitate motivation in struggling learners. A qualitative paradigm was utilized to study three participant dyads, each one consisting of a child with a language disorder and a speech-language pathology graduate student. The primary source of data was video transcript analysis of a total of 17 representative shared reading sessions. The findings of this study demonstrate that motivation to participate in shared reading is manifested in the continued willingness of the child to participate in shared reading and that motivation was facilitated by the graduate clinician via a variety of therapeutic strategies. </p><p> Eleven common patterns emerged. 1) motivation as sustained participation, 2) a distinct set of functional therapeutic strategies were employed, 3) a wide range of therapeutic strategies were employed, 4) variable but systematic application of the different strategies, 5) interweaving of bursts of mediation and singular episodes of mediation, 6) utilization of collaborative therapeutic strategies/culture of co-investigation, 7) a high level of support prior to turn allocation, 8) successful communicative and reading attempts, 9) responsive collaboration by participants, 10) engagement even in the presence of struggle, and 11) rare occurrence of avoidant behaviors. Results indicate that motivation to engage in learning to read was the result of a wide range of instructional, evaluative, and interactional strategies that worked together to promote motivation to read. In response to these strategies, each participant produced responses that were overwhelmingly successful and even expected. These key variables helped to facilitate therapeutic interaction that was characterized by motivation and success.</p><p> Ultimately, it is apparent that motivation to read is best facilitated by complex, multi-faceted strategy use led by instructional strategies with a significant presence of evaluative and interactional strategies. It can be concluded that the participant behaviors that indicate motivation include primarily successful, expected responses that were facilitated by meaningful, strategic interactional devices.</p>
9866

Numerical Modeling of Fluid Flow and Heat Transfers in Porous Media

Spezia, Kyle 03 February 2016 (has links)
<p> Field studies of Cordilleran metamorphic core complexes indicate that meteoric fluids permeated the upper crust down to the detachment shear zone and interacted with highly deformed and recrystallized (mylonitic) rocks. The presence of fluids in the brittle/ductile transition zone is recorded in the oxygen and hydrogen stable isotope compositions of the mylonites, and may play an important role in the thermomechanical evolution of the detachment shear zone. Geochemical data show that fluid flow in the brittle upper crust is primarily controlled by the large-scale fault-zone architecture. </p><p> We conduct finite element numerical modeling of groundwater flow in an idealized cross-section of a metamorphic core complex. The simulations investigate the effects of crust and fault permeability fields on groundwater flow. Results show that fluid migration to mid- to lower-crustal levels is fault-controlled and depends primarily on the permeability contrast between the fault zone and the crustal rocks. High fault/crust permeability ratios lead to channelized flow in the fault and shear zones, while lower ratios allow leakage of the fluids from the fault into the crust.</p>
9867

Category Specific Semantic Impairments

Kline, Valerie 03 February 2016 (has links)
<p> Category-specific semantic deficits (CSSD) result in the inability to recognize, recall, and/or remember objects from a particular semantic category. There is a common pattern of impairments observed in CSSD patients that is reviewed in Section One. In Section Two, I used a tempo-matching speeded word verification task to investigate the early stages of semantic memory to examine the similarities between healthy participants under time pressure and the patient data. Specifically, I sought to produce in the latter the reversal of the basic level effect found in CSSD, and to examine healthy participant data for other CSSD trends. The speeded methodology generally failed to replicate the reversal of the basic level effect, except for several specific items at the shortest response deadline. The final study in Section Two examines the effect of semantic relatedness on this task. Three types of semantic relatedness each reduced the speed and accuracy of responses relative to unrelated conditions. Section Three provides an overview and discussion of the results. The failure to replicate the reversal of the basic level effect suggests that speeded classification of neuropsychologically relevant stimuli does not share a common etiology with CSSD.</p>
9868

Development of an Integrity Evaluation System for Wells in Carbon Sequestration Fields

Li, Ben 03 February 2016 (has links)
<p> Carbon sequestration is a promising solution to mitigate the accumulation of greenhouse gases. Depleted oil and gas reservoirs are desirable vessels for carbon sequestration. It is crucial to maintain the sealing ability of carbon sequestration fields with high concentrations of CO<sub>2</sub>.</p><p> A systematic well integrity evaluation system has been developed and validated for carbon sequestration fields. The system constitutes 1) a newly developed analytical model for assessing cement sheath integrity under various operating conditions, 2) quantifications of well parameters contributing to the probability of well leakage, and 3) genetic-neural network algorithm for data analysis and well-leakage probability assessment.</p><p> A wellbore system consists of well casing, cement sheath, and formation rock. A new analytical stress model was developed. The new analytical model solves for the stresses in the casing-cement sheath formation system loaded by the isotropic and anisotropic horizontal in-situ stresses. Further analyses with the analytical model reveal that Young&rsquo;s modulus of cement sheath is a major factor that contributes to the sealing ability of the cement sheath, while Poisson&rsquo;s ratio and cohesion play less important roles in the cement sheath sealing ability. The cement sheath in the shale formation exhibits higher sealing ability than that in the sandstone formation. The sealing ability of weak cement is higher than that of strong cement.</p><p> Descriptive quantifications of well parameters were made in this study for analyzing their effect on the probability of well leakage. These parameters include well cement placement relative to aquifers and fluid reservoir zones, cement type, cement sheath integrity in operating conditions, well aging, and well plugging conditions. It is the combination of these parameters that controls the probability of well leakage. A significant proportion of wells were identified as risky wells in these two fields. It is concluded that the well trained neural network model can be used to predict the well leakage risk over the CO<sub>2</sub> sequestration lifespan, which can promote prevention activities and mitigations to the CO<sub>2</sub> leakage risky wells.</p>
9869

Warning Label Modalities and Message Order Effects for Digitally Enhanced Models in Advertising

Squyres, Rebecca T. 03 February 2016 (has links)
<p> Unbeknownst to many viewers, models in advertising are often digitally enhanced, meaning that there are digital edits made to the models' faces and bodies. Viewers participate in social comparison when they compare their lives and bodies to the models they see in the media. This social comparison can often lead to negative effects on their self-esteem, social assurance, and body satisfaction. Some U.S. legislatures believe that warning labels could help curb these negative effects. The little research on warning labels for digitally altered models in advertising has demonstrated that warning labels can be a successful tool in limiting social comparison with the model. </p><p> This research will build on the literature by examining the extent to which type of warning label (visual, verbal, both visual and verbal) and placement of warning label (before or after) intervene with participants' self-esteem, social assurance, and body dissatisfaction levels by using a 3 X 2 full factorial experimental design with control group. </p><p> Volunteer participants were selected from CMCN 100 classes. Of the participants, 178 females ages 17&ndash;33 were used in analysis. One-way ANOVA testing disproved any main effects the type or placement of warning labels have on self-esteem, social assurance, and body dissatisfaction. No significant interaction effects were found for warning label type and its placement on self-esteem, social assurance, and body dissatisfaction</p>
9870

Blues signifying and the trickster figure in the improvisations of Johnny Hodges, Charlie Parker, and Ornette Coleman

Calhoun, Fraser C. 03 February 2016 (has links)
<p> The goal of this study is to relate blues characteristics as they appear in the playing of Johnny Hodges, Charlie Parker, and Ornette Coleman, to blues lyrics, Signifying, the artists&rsquo; life experiences, and to the ancient cultural icon Esu-Elegbara. This study reviews the theory of Signifying, discusses existing literature on blues Signifying, and investigates select biographical information of each player. In addition, the study presents and analyzes transcriptions of jazz improvisations for each artist and reveals and investigates their blues characteristics. The study then contextualizes discovered blues characteristics in terms of blues lyrics (and consequently their melodies), the meaning of these lyrics, and later their respective artist&rsquo;s life experiences. Findings show that each artist has personal similarities to the Yoruban cultural figure Esu-Elegbara. These similarities assist in revealing the Signifying nature of the blues characteristics in the case studies&rsquo; improvisations. </p>

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