The effect of hemodynamics on cardiovascular disease (CVD) is very important since CVD is the number one killer nationwide and around the globe. Coronary artery disease (CAD), also called arteriosclerosis, is a common disease found in human arteries, including coronary arteries and the common carotid artery. The abdominal aorta is also affected by atherosclerotic aneurysm. Formation of atherosclerosis obstructs the blood flow in arteries and changes the hemodynamics pattern. Numerical and experimental modeling in a tapered artery using turbulent models has been untouched so far. To investigate the cause of atherosclerosis and atherosclerotic aneurysm, simulations were done using the finite volume method via FLUENT 6.3.26. Wilcox’s two-equation standard κ-ω model was used for numerical simulation of a tapered artery and abdominal aortic aneurysm. The tapered artery had a diameter reduction of 25 percent at the stenosed area. The two-equation turbulence κ-ω model was employed on a geometry to validate the numerical results with velocity profiles of experimental results. Blood was assumed to be Newtonian in all simulations. The main objectives of this thesis were as follows: 1. To study the shear stress and blood streamlines of tapered artery at different Reynolds number using the κ-ω model. 2. To simulate the pulsatile flow conditions on a tapered artery and abdominal aortic aneurysm. 3. To predict and validate the kick-start of atherosclerosis based on hemodynamic conditions. 4. To study the effect of turbulent viscosity on shear stress. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering.

The positive impact of physical activity is well-documented (Rejeski, Shannon, and Mihalko, 2001). Sedentary living takes the risk of morbidity and mortality from coronary heart disease and stroke and doubles it (Troisi, Heinold, Vokonas, & Weiss, 1991). In addition to the health benefits related to physical activity there are also positive psychological implications associated with regular physical activity. In fact, physical activity can help off-set the daily stressors of life. Mood can be enhanced and anxiety reduced through participation in aerobic exercise. Many studies have explored ways that exercise can promote psychological health by improving mood and reducing anxiety (Johannson, 2007). This purpose of this project was to determine the impact a regular physical activity program can have on older adult’s mood regulation. Twentyeight women (X= 71 ± 5 yrs) were recruited. Individuals voluntarily chose to participate in the Well-Rounded Exercise Program (WellREP) and agreed to complete the questionnaires related to their current mood state. Participants were screened using the EASY (Exercise And Screening for You) Screening tool in order to determine the appropriateness of their participation. The Well-Rounded Exercise Program , a 4-componenet routine to increase physical activity, was the intervention. The program includes four components: cardio-respiratory, flexibility, strength, and balance. Mood was evaluated using five concepts: quality of life, well-being, satisfaction with life, self esteem, and happiness. Of the 28 participants who started the study, 15 completed both pre and post testing, thus the program experienced a large amount of attrition which was attributed to the nature of the questionnaires. Result revealed significant improvement in physical activity and one measure of mood – happiness. The lack of improvement on the majority of the mood measures may be attributed to a ceiling effect in which participants were a relatively happy group leaving little room for improvement. / Thesis (M.A.)--Wichita State University, College of Liberal Arts and Science, Dept. of Gerontology.

Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Mathematics and Statistics.

The evolution of hand-held devices and portable machines started the increase in demand for reliable, secure, and faster means of communication from wireless LAN infrastructures. This has lead to an enormous increase in the size of networks, which in turn has increased the cost and power consumption of access points and switches in the network infrastructure. While managing demand, networks become underutilized with less traffic demands and over utilized with more traffic demands. This research tends to discuss the best designs for maximum efficiency in terms of power and cost while retaining the best user experience. Designs were mainly evaluated based on the benefits of a centralized structure and a non-centralized structure. Furthermore, in order to understand the differences and make centralized structure more efficient in terms of power and cost, a new algorithm was designed with convex hull approach and was also implemented in the emulator kind of network testbed generating outstanding results and evaluations. The algorithm proposed in this thesis and the resulting design, if implemented in the future, could mean 60 percent additional savings in power consumption and costs. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.

Buffers are inventory held in between machines to avoid stockout of parts. When a company has large buffer quantities between machines the inventory holding cost increases. Reducing the amount in a buffer increases the chance of stockout and hence will have a direct impact on the throughput of the line. Hence there is a need to maximize the throughput of the production line for a minimum quantity of buffers carried between machines. In large volume manufacturing, homogeneous unreliable serial parallel production lines are typical. For this line, a method is developed to identify the buffer allocation that maximizes the throughput of the line with a constraint on the maximum buffer size that can be held in the line. The developed method is implemented in case studies to identify buffer allocation that maximizes throughput. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering.

In this paper, we introduce a novel cycle identification algorithm using Matlab programming to automatically identify cycles in tidal breathing signals. The algorithm is designed in four steps using filtering, derivation, and other signal processing techniques. To verify the effectiveness of the proposed algorithm, its results are compared with those of cycles identified manually by a human coder. Simulations results show that despite the complexity of the respiratory signals, the proposed algorithm can identify cycles more correctly and more efficiently than cycles identified by hand-coding. This algorithm can serve as an important first step toward timely identification and coding of more complex respiratory signals, such as those underlying speech productions. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.

This thesis explores the bit error rate (BER) characteristics of a convolutional decoder constructed of a backpropagation neural network (NN) using a newly proposed input shifting window. Due to the fact that each NN is independent and unique, multiple NNs are placed in parallel and utilize the majority rule to further improve BER performance. NNs are efficient in complex statistical systems because of their inherently fast parallel-processing speed and pattern-recognition abilities. It was found that with a code rate of ½ and a constraint length of K = 3, a NN with the optimal convolutional code generator polynomial, which is non-systematic, has poor performance and a NN with a systematic convolutional code generator polynomial shows comparable performance to a conventional hard-decision Viterbi decoder using the optimal convolutional code generator polynomial. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.

There has been a long history of research into the possible relationship between anxiety and stuttering. Despite this history, however, relatively little research has focused on components of anxiety and how these components combine to create fear responses in both fluent speakers and persons who stutter. This study was designed to determine if differences existed between fluent speakers (FS) and persons who stutter (PWS) with respect to components of fear described by Reiss’ (1991) expectancy model. Twenty PWS and twenty FS were provided with a hypothetical social communication scenario and asked to complete measures related to predicted anxiety, anxiety sensitivity, fear of negative evaluation, and expectancy. Results indicated that the FS group behaved as predicted by Reiss’ model but the PWS group did not. Results suggested that clinicians working with people who stutter may tend to view their client’s anxiety based upon their own experiences. Clinicians should explore the client’s components of fear and how it is playing a role in their experience of stuttering. / Thesis (M.A.)--Wichita State University, College of Health Professions, Dept. of Communication Sciences and Disorders.

This study looked at the exchange of online and offline social capital among a group of people who share both an online network (Twitter users) and live in the same offline community (Wichita, Kansas). The study, recognizing that communities are social networks, utilized a triangulated methodology including a survey, focus groups and a case study to analyze social capital in online and offline networks, similarities and differences in the experience of social capital online and offline, and the transference of social capital between online and offline networks. Results indicate the presence of both online and offline bridging and bonding relationships and the transference of social capital between them. Implications of these findings for the enhancement of offline communities are discussed. / Thesis (M.A.)--Wichita State University, College of Liberal Arts and Sciences, The Elliott School of Communication.

Metal cutting subjects the material being cut to high strain rates (103 -106/s) and strains>100% within the primary shear zone (PSZ). This thesis is aimed at quantitative measurement of the strain, strain rate and flow stress in the PSZ in order to provide data that can be used to verify and improve high strain rate material models. An experimental study of the cutting forces, chip thickness, and velocity fields in the PSZ, has been carried out during the cutting of AISI 4340 steel in three different tempers; hot rolled steel, hardness 18HRc, referred to as AISI 4340HR; hot rolled steel with additional 50% cold rolling, hardness 27HRc referred to as AISI 4340CR; Heat treated (quenched and tempered) steel, hardness 45HRc, referred to as AISI 4340HT; and Titanium alloy Ti-6Al-4V. Kennametal make KC510M inserts with edge radius 6μm is used for all the cutting experiments reported and is mounted on a tool holder which provides a rake angle of 30o and a clearance angle of 4o. The KC510M inserts are used in an effort to minimize the side spread of the material. A new type of ultra high-speed camera is used to capture sequential and high resolution microphotographs of the PSZ during machining at frame rates ranging from a few kHz to 1MHz. The velocity fields are obtained by 2D cross-correlation of sequential images and the gradient of the velocity field yields the strain rate field. Each experiment yields four to seven strain rate fields from which the average strain rate field is obtained. Average strain rate fields found in multiple experiments are averaged to obtain the overall average strain rate for the cutting condition. As the shear velocity (Vs) needs to be same throughout the chip width for the chip to be moving as a rigid body, the shear angle has to be constant from the sides to the mid-section of the chip. Two independent estimates of the shear angle, from the velocity field and from the chip thickness, show reasonable correlation. The shear angle from chip thickness is an average over each experiment, while the shear angle from velocities is an instantaneous value and is taken to be the true value. The 'indentation' component of the cutting forces is calculated from the measured cutting forces using the ratio of flow stress in the PSZ to the contact pressure observed in finite element analysis (FEA) simulations. The flow stress along the nominal shear plane is computed from the measured shear angle and cutting forces, after removal of the 'indentation' component. The thickness of the PSZ is smaller and the peak strain rate is higher for AISI 4340CR compared to AISI 4340HR, due to reduced work hardening. While the forces are found to be nearly the same, the vii shear angle is larger and the flow stress is smaller for the AISI 4340CR material. For the AISI 4340HT, the flow stress is found to be about 10-20% larger compared to AISI 4340HR. The PSZ is typically parallel sided and shows a single peak in the CD direction along the PSZ while cutting AISI 4340HR, AISI 4340CR, AISI 4340HT and Ti-6Al-4V. The strain rate near the cutting edge is high and gradually decreases as we move towards the free end while cutting AISI 4340HR and AISI 4340CR. The strain rate near the cutting edge and the free end of the PSZ is high but lower in the middle of the PSZ, while cutting AISI 4340HT. The mode of deformation while cutting AISI 4340HR and AISI 4340CR is inhomogeneous, meaning the same regions of the work material accumulate deformation and the shear ‘plane’ moves with the material over time, till eventually switching over to a new shear ‘plane’. The high-speed images of the PSZ while cutting Ti-6Al-4V clearly show localized bands of shear separated by larger bands of less deformed material, implying the deformation continues to concentrate within the same region of the material. The chip is thinner and quantitatively shows that the shear band is at the same region with respect to the workpiece. We have compared and contrasted the deformation process of Ti-6Al-4V with that of AISI 4340HR and AISI 4340CR. For the same cutting speed and feed, the strain rate while machining Ti-6Al-4V is higher and the PSZ narrower when compared to AISI 4340CR. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering.