This study presents the experimental results of time-temperature dependent viscoelastic behavior and cure kinetics of two commercial carbon fiber/epoxy prepregs, IM7/977-2 unidirectional tape (UD) and IM7/977-2 plain weave fabric (PW). An in-depth study on the oscillatory and transient rheological behavior of prepreg composites is conducted using a dynamic mechanical analyzer (DMA) and the study of cure kinetics is conducted using a differential scanning calorimeter (DSC). A novel experimental methodology is proposed in this study to describe the stress relaxation behavior of prepreg composites during cure. Time- and cure-dependent stress relaxation behavior of prepreg composites is studied in three in-plane directions: 0, 45, and 90 degrees of the laminates. Several other factors, such as the mismatch of fiber orientation of adjoining plies, stacking sequence of the laminate, and relative position of the plies with respect to the neutral axis are considered to study their effects on the stress relaxation behavior during cure. The stress relaxation behavior of cured composites is obtained by utilizing the time-temperature superposition (TTS) principle. TTS study on UD laminates (in 0, 45, and 90 degree fiber directions) is conducted at four distinct cure states, whereas the PW laminate is studied in the same fiber directions but at a fully cured state only. Experimental results are used to predict the life cycle of the composite products by generating the stress relaxation master curves for different combinations of fiber orientation and cure states. The study shows that the relaxation modulus during cure is case dependent, which leads to the assumption that the relaxation of process-induced stresses during cure varies for different conditions. Moreover, when comparing the performance of UD and PW prepregs, it shows that the PW laminate relaxes more residual stress than the UD laminate during cure. At cured condition, the PW material shows better long-term mechanical performance than UD material. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering

Childhood obesity is on the rise, and many critics claim that environmental factors, such as screen-based media, are a contributing factor to this epidemic. Video games have gained popularity among this age group, especially exergames, which have researchers pondering the physiological effects of playing exergames. The purpose of this study is to examine the differences in heart rate achieved and maximum heart rate achieved between three exergaming systems, and to analyze the intensity level achieved while playing exergames. Twenty males and females ages 8-12 were in this study. Participants were allowed three sessions to become familiarized with equipment and were allowed to play three game systems: (1) Nintendo Wii, (2) Dance Dance Revolution (DDR), (3) Xbox Kinect. Heart rate monitors were worn on the wrist by each participant and were used to record heart rates during six exergaming sessions. Participants played one type of exergaming system for 30 minutes each session, collecting heart rate seven times. Heart rate data were compared to baseline measures, between the threeexergaming systems, and to heart rate thresholds of 50 percent and 70 percent of maximum heart rate. Repeated Measures ANOVA did not show significance for heart rate achieved and heart rate ranges achieved (p=0.563, p= 0.738 respectively). Sixty-four percent of participants achieved heart rates that ranged between set thresholds of 50 percent and 75 percent on all three exergaming systems. Thus, exergaming can be used as physical activity to supplement other forms of physical activity. / Thesis (M.Ed.)--Wichita State University, College of Education, Dept. of Human Performance Studies

The onset of dysphagia (swallowing difficulty) is associated with increasing age and the diseases that frequently occur with increasing age. Dysphagia increases the risk of dehydration and malnutrition with subsequent declines in body composition, physical health, and quality of life. The purpose of the present study was to administer a set of valid objective and perceptual measures to document (a) physical health, and (b) nutrition and hydration, relative to (c) swallowing function in 15 self-reported healthy older women in a Continuing Care Retirement Community. Statistically significant (p < 0.05) correlations were identified between perceived physical health, emotional well-being, and reflux symptoms and objective measures of breathing capacity, blood oxygen level, and tongue strength and endurance. The consumption of a regular, unrestricted diet was significantly associated with Eating Duration and Eating Desire on the Swallowing Quality of Life (SWAL-QOL) survey. Objective measures and participants��� responses on the SWAL-QOL identified a subgroup of older adults who were experiencing swallowing difficulties. Results confirm the importance of including both objective and perceptual measures of physical health, nutrition, hydration, and swallowing function in a screening protocol for older adults in residential care to identify those at-risk for developing dysphagia. / Thesis (M.A.)--Wichita State University, College of Health Professions, Dept. of Communication Sciences and Disorders

The study of cavity flows has played a crucial role in understanding the aeroacoustics and aerodynamics of bodies with cavities. This new understanding has allowed challenges such as reduction in noise levels to be addressed. It has also helped in the reduction of structural resonance and fatigue, and to ensure the proper release of weaponry. In this thesis, a brief study was conducted on the flow-field characteristics of various cavity geometries. These cavities were partially covered, and the depth of the trailing edge of the cavities was varied. The flow field was set at Mach 0.7, and sound pressure levels were obtained using numerical simulations. Detached eddy simulations, which have proven to be successful in previous research work, were used in the present study. The simulations were carried out for a flow time of 0.05 sec. The cavity with the highest trailing edge depth was found to have a greater sound pressure levels; however, no resonance phenomenon was observed. A grid-independency study and a validation study were conducted using detached eddy simulations, and the convergence and stability of the results were investigated. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering

For an efficient damper design, a design engineer always faces the challenge of providing the largest forces in the most compact and efficient envelope. It is important to identify the nature of the force required at the output in order to configure the damper to produce more force in less space. This thesis takes into consideration the role of MagnetoRheological (MR) fluids played when used in conjunction with dampers. In order to achieve this purpose, a finite element model is constructed to analyze and examine a 2-D axisymmetric MR damper. The results obtained in this thesis will help designers to create more efficient and reliable MR dampers. With the help of finite element tools, some design analyses are created to change the shape of the piston in the damper or other parameters in the model. The main benefit of this research is to show a 2-D MR damper and generate the magnetic flux density along the MR Fluid gap. The magnetic saturation is detected by looking at the nodal solution for the magnetic flux density. Increasing the current in the model, results in an increase in magnetic induction. Three different configurations of an MR damper piston were studied in order to determine how changing the shape of the piston affects the maximum force which the damper provides. The variations provided in the MR fluid gap were plotted for magnetic flux density contour before and after reaching the rheological saturation. By increasing the current, the color spectrum of the magnetic flux density will shift from the MR fluid gap to the piston centerline. As the current provided to a reasonably good amount, the force obtained was to a good extent. But it reaches saturation at around 2 amps. Thus for constraint or heat build up limitations, the second model could work the best among the three designs that we considered. For cases where higher electrical currents can be tolerated, model 2 would be the most advantageous design, since it provides the largest force among the three models. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "December 2006."

Access to mobile communication technology is a characteristic that makes today’s learners different and presents challenges and opportunities to develop twenty-first century skills in a globalized society. This qualitative study involved students and teachers using synchronous and asynchronous web-based social networks and recording software to communicate and compose music. Dialogue was captured and analyzed for levels of interaction and mindsets to determine if such a collaborative could cultivate an awareness of others’ perspectives and the feasibility of using social networks in K-12 educational settings for this purpose. There were strong indications that global reach projects using technologies in K-12 education do have the potential for students to become aware of others’ perspectives; however changes in educational policy are needed. / Thesis (Ph.D.)--Wichita State University, College of Education, Dept. of Educational Leadership

This research attempted to find the relationship between the consistent practice of Sustained Silent Reading (SSR) and a student’s lexile score. Two English I classes in an urban high school completed surveys that focused on a student’s attitude toward recreational and school reading. The Scholastic Reading Inventory (SRI) provided the two English I classes a lexile score. Class A practiced SSR three days a week, while Class B did not. After the research period of twelve weeks, the two English I classes were given post-surveys similar to the pre-surveys and the SRI. The post-surveys from Class A were compared to the post-surveys from Class B. The post-SRI scores of Class A were compared to the post-SRI scores of Class B. Any changes or shifts in student attitude were measured. The hypothesis was found plausible. Significant differences were found in both the survey and SRI data. Class A had higher SRI scores than Class B. Additionally Class A had a better overall attitude toward reading than Class B. / by Kellie Sue Birmingham. / Thesis (M.Ed.)--Wichita State University, College of Education, Dept. of Curriculum and Instruction / Includes bibliographic references (leaves 34-37). / "May 2006."

Improving students’ reading fluency is a major challenge heard throughout many classrooms, and identified by the National Reading Panel. Several research studies indicate that one way to improve fluency is through reader’s theater. Those studies also point out that the positive impact from reader’s theater goes beyond fluency to also boost readers’ confidence, motivation, and comprehension. This thesis was designed to examine the effects of reader’s theater on sixth grade students’ fluency, comprehension, and reading attitude. It was also designed to measure the interrelatedness of all of those aspects. The findings indicated statistical significant differences between the fluency pre and post test scores. Statistically, significant differences did not emerge from comprehension, self-concept, and value of reading pre and post test scores; however, qualitatively gains were seen in the area of self-concept and value of reading. / by Jennifer K. Sailer. / Thesis (M.Ed.)--Wichita State University, College of Education, Dept. of Curriculum and Instruction / Includes bibliographic references (leaves 27-29).

Students with learning disabilities use prior knowledge differently than students without learning disabilities. This paper examines what happens to reading fluency, words per minute, and reading comprehension when prior knowledge is activated. By using two reading passages at the fourth grade level, students read one passage without prior knowledge activation and another with prior knowledge activation. The students were timed for words per minute. The reading errors were noted for fluency, and questions were asked to measure comprehension. While students’ individual scores both increased and decreased in all areas when prior knowledge was activated, students with learning disabilities did increase their reading comprehension on average. / by Amber D. Warsnak. / Thesis (M.Ed.)--Wichita State University, College of Education, Dept. of Curriculum and Instruction / Includes bibliographic references (leaves 35-39). / "May 2006."

Composite anisotropic materials are rapidly gaining popularity in various applications. A global trend is towards an increases utilization of these advanced materials in a variety of structural applications. The pump and pipeline industry, and aerospace industry are the areas where use of fiber reinforced plastics have potential advantages over conventional materials. This thesis presents the results of an investigation to predict the behavior of filament wound glass fiber reinforced composite pipe subjected to different types of biaxial loading which typically occur in vertical diffuser pumps. In this study the influence of lay-up configuration and stacking sequence on the failure strength of a multi-angle glass fiber reinforced polymer composite tube was investigated by using finite element analysis. Published experimental results are taken as the basis for validation of the finite element analysis results. MSC-PATRAN was used to create a half model of the composite tube, and LS-DYNA software was used to perform the analysis. It was observed from the analysis that, the winding angle and the stacking sequence have a significant effect on the structural failure strength of the tube. Additional testing would be needed to verify these results; however the study demonstrated that finite element simulations could be used to accurately predict the performance of glass fiber composite tube under biaxial loading, and can be effectively used for direct applications in designing tubular structural components in centrifugal pump and other industries. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering. / "May 2006." / Includes bibliographic references (leaves 87-90)