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Energy expenditure during chewing: a comparison of two measurement methodsYenter, Jaclyn 05 1900 (has links)
Older adults with chewing and swallowing difficulties frequently report increased fatigue and effort, or energy expenditure, during eating. Energy is defined as the ability to perform work. It is most accurately measured through an examination of the gaseous composition of inhaled and exhaled air at rest and during activity using laboratory-based indirect calorimetry. There is a need for a valid measure of energy expenditure that can be used to document the effort involved in eating and swallowing in natural contexts. The purpose of the current study was to determine the concurrent validity of the portable SenseWear® system compared to indirect calorimetry during a simulated eating task. Nineteen university students served as participants. Each was connected simultaneously to indirect calorimetry and SenseWear® systems. Energy expenditure was obtained while participants chewed gum and swallowed repeatedly. Pearson product-moment correlations showed a close relationship (p < 0.05) between the two measurement methods. Mean Mid-Arm Muscle Circumference measures also correlated positively with both measurement methods, reflecting the influence of body mass on energy expenditure. Results support the use of the SenseWear® system to measure energy expenditure in chewing and swallowing in natural contexts, particularly for adults with chewing and swallowing difficulties. / Thesis (M.A.)--Wichita State University, College of Health Professions, Dept. of Communication Sciences and Disorders.
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The impact of MAC contention and route failures on burst losses in saturated ad hoc networksZaman, Shahid 05 1900 (has links)
Medium access contention and route failures in the saturated wireless ad hoc networks increase the average number of transmission attempts required to successfully deliver a frame. MAC contention and route failures also cause burst packet losses at the network layer, which results in the degradation of real-time application quality. In this thesis, the effect of MAC contention and route failures is analyzed on stationary and mobile saturated ad hoc networks for variation in the network size and data rates. In stationary networks, MAC contention has a dominating effect on burst losses. In mobile networks, route failure causes a similar effect. An increase in the data transmission rate affected the burst losses in both stationary and mobile networks / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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Development of low pressure filter testing vessel and analysis of electrospun nanofiber membranes for water treatmentNilsen, Kyle 05 1900 (has links)
Polymeric electrospun nanofibrous membranes were investigated for use in water filtration applications. A customized pressure vessel was designed according to the American
Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) to be used to test the membrane for its filtration properties. Low pressure filtration was focused on due to
previous research that suggested that high pressure water testing of electrospun polymeric
nanofibrous filters could decrease the filtration capability by expanding the pore size within the
membrane. During testing it was found that this technology does reduce pathogens but will only
remove a portion of them per pass, and thus is not adequate for use as a one pass pathogenic
filter. The filter was found to be well suited for the reduction in the amount of suspended and
dissolved solids, increasing clarity, and reduction of odor. A scanning electron microscope
(SEM) was used to study the electrospun fibrous pads to narrow down on an ideal parameter set
that gave the desirable characteristics for the application of filtration. The composition of the polymer, and electrospinning parameters, were also manipulated to give a hydrophilic, or
absorbent, membrane to facilitate a low pressure differential for filtration. It was demonstrated
that this type of filtration membrane can be manufactured inexpensively while not requiring
electricity or other external power source to generate large pressure differentials and flow. This
is desirable because it allows this technology to be used in areas where both basic utilities and
clean water are limited, for example in remote Africa and India. It was also shown that this filter
has benefits over best selling commercial water filters currently on the market. This technology
may be best suited for enhancement of tap water where healthier and cleaner water is desired.
Pre-filtration of reverses osmosis (RO) or other ultrafine filter system, to increase the life of the
primary filter while decreasing fouling and maintenance may be another application. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
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An efficient and low cost 3D compass gait biped an economical platform for control system developmentAshton, John A. 05 1900 (has links)
A compass gait biped is a theoretical model of a human that is physically walking. The
compass gait model is a 2D planer representation that simplifies the calculations required to
mathematically describe the human walking gait. The model assumes stability in the sagitial
plane and also ignores any ‘foot’ contact with the ground plane other than the time assigned and
positionally assigned Plant-Foot.
This thesis starts at and expands from the 2D compass gait model, firstly to a 3D
computer simulated model and secondly to a physical and operational 3D model. The computer
simulation is to provide proof of feasibility, demonstrate that it will be physically operational,
and to document its’ probable power requirements. The models’ purpose is to provide a platform
for a control system, such that the control system can control the 3D model with a resulting
human-like walking gait. The requirements for the 3D model/control system platform are that it
is efficient and extremely economical. It must be very simple to fabricate consisting primarily of
common ‘off the shelf’ parts and it must also be scaleable.
The completed 3D simulation model provided torque data, natural frequency data, and
operational proofing that enabled a virtual straightforward fabrication of the physical model.
The completed physical model walks in a manner that is a near mirror image of the simulated
model. It provides a working human gait simulation that can be easily controlled by an onboard control system and that by design requires minimal control. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
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H2 control of singularly perturbed aircraft systemZaveri, Viral Shailesh 07 1900 (has links)
The objective of this research is to develop an analytical approach to control two-time-scale systems operating under certain noise parameters. This approach addresses two important design criteria: augmentation of large-scale system with disturbance model and its two-time-scale representation, and order reduction of the large-scale systems for reduced controller design complexity. The problem of large-scale system with Gaussian noises is solved as the stochastic system implementing linear-quadratic Gaussian control. Order reduction method uses singular perturbation techniques for the simplicity of control algorithms. Control law design process for a singularly perturbed stochastic system includes implementation and comparative analysis of optimal, composite, and reduced controller techniques. Practical model, longitudinal dynamics of digital fly-by-wire F-8C fighter aircraft, illustrates the validation of the proposed concepts. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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Parametric study of stress concentration of single and double bolted lap joints between adhesive bonded aluminum laminatesVinnakota, Lakshman 07 1900 (has links)
In the distant past, adhesive materials were considered to be a kind of mere glue. But today adhesive materials are used extensively in the field of manufacturing because of the good properties they exhibit. Adhesive bonded aluminum laminates are well known materials that belong to the family of metal laminates. Adhesive bonded aluminum laminates are made by joining several thin sheets of aluminum. These sheets are bonded by an adhesive material in between. The adhesive bonded aluminum laminates when compared to the monolithic aluminum plates, exhibit very good mechanical and chemical properties. They also exhibit some useful properties such as weight reduction, capability of withstanding high loads, thermal resistance, etc. Because of this, they are widely used in aerospace, marine and automobile fields, particularly in manufacturing of doublers plates.
Optimizing the design of structural joint will definitely improve the load carrying capability of the structural joint. Identifying the significant factors that affect the structural joint is one way to avoid failure at the joints. The main purpose of this study is to predict the stress concentration around the hole in single and double lap joints of adhesive bonded aluminum laminate. A three dimensional finite element model is developed in ABAQUS to know the effect of stress concentration and is validated by comparing the results of the finite element model with the results obtained from theoretical closed form solution. The present study shows the relationship between the stress concentration around the hole and the Young‟s modulus of the adhesive material, Radius of the fastener holes, Distance between the fastener holes, position of the adhesive layer and number of the adhesive layers. The results obtained from this parametric study are analyzed in a design of experiments software to determine the significance of each parameter. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
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Application of a global screening method to probe the role of epigenetics in an experimental model of DES-induced, estrogen-dependent uterine cancerSimpson, Megan Odetta 07 1900 (has links)
Diethylstilbestrol (DES), a synthetic estrogen, was widely administered to pregnant women between 1947 and 1971 on account of a misconception that it could prevent miscarriages. Due to the wide use of this estrogen-mimicking drug, at least four million women and their fetuses were exposed to DES. The offspring of these women developed various reproductive tract abnormalities, including cancer. We primarily focus on neonatal DES-induced abnormalities in the uterus and this study analyzed altered DNA methylation patterns.
DNA methylation is a major component of the emerging topic of epigenetics and epigenetic modifications may be just as important to the development of cancer as are the classic genetic phenomena of DNA mutations. We use Syrian golden hamsters to study the consequences of early developmental DES exposure. The methodology of Methylation Sensitive Restriction Fingerprinting (MSRF) was tested as a means to screen for the presence of altered DNA methylation patterns in uteri from control vs. neonatally DES-treated hamsters. As a result of this screening process, we found 9 DNA fragments containing abnormal methylation or demethylation events. Of these 9 fragments, 5 showed enhanced hypermethylation, 2 showed complete hypermethylation, and 2 showed incomplete hypomethylation. Sequence analyses yielded results and alignment matches for 5 of the 9 fragments of interest, 4 of which showed significant homologies to regions of the mouse and rat genomes. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences
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Modeling human leg arteries: a comparison of conditions and diseasesRoodhouse, Amanda 07 1900 (has links)
Peripheral artery disease is a condition that is prevalent among the American population. It is caused by plaque buildup in arteries, known as atherosclerosis, other than those arteries in the heart and brain. While peripheral artery disease is not generally life threatening, complications from this disease can lead to intense pain, amputation and severe loss of quality of life. Most of the studies focusing on the lower limb arteries have been finite element studies looking at the bending effects on stents. These models are useful for stent design; however do not encompass the effects that curvatures, bifurcations and bends have on the fluid mechanics of blood flow.
This thesis creates several computational fluid dynamics models of the Superficial Femoral, Deep Femoral and the Popliteal Arteries in an attempt to evaluate diseases and conditions that may contribute to peripheral artery disease. This includes the varying positions that the artery many take on during ordinary leg movement, the effects of pulsating flow, the effects of stenosis and stents, as well as the effects of increased and decreased viscosity caused by variable hemotocrit count.
The results of these models were examined using various graphs of the mass flow rates, velocity profiles, wall shearing stress and static pressures. It was shown that stead state simulations will underestimate wall shearing stress and that diabetic blood will nearly double the wall shearing stress experienced in the arteries. The curvatures in the arteries will create areas of increased and decreased wall shear stress, as well as generate recirculation zones. Higher hemotocrit count decreases the recirculation zones and lower hemotocrit count increases these zones. These areas of low wall shear stress have a greater chance of forming plaque buildup; whereas the increased areas of stress can cause aneurisms in the arteries and put additional strain on the stent implants, possibly contributing failure. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
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Measurement of energy consumption in Wireless LANs and Radio Frequency Identification systemsRamamoorthy, Suresh 07 1900 (has links)
As mobile hand-held devices such as cell phones and personal digital assistants are battery
operated, it is important to minimize their energy consumption. The limited lifetime of the battery
is always a problem for all portable devices. Although battery technology has undergone a massive
development over the years, it has not kept pace with other technologies. Therefore, research needs
to be done to use the limited life time of the battery in an efficient way.
With developments in science and technology, the power consumption of portable devices
has been brought down due to the decrease in the size of the display and optimization of components.
The trend toward smaller sizes of portable devices involved is responsible for the wireless
network interface consuming a larger share of overall power consumption of a system. In order
to optimize the power consumption of wireless communication, we should be aware of the power
consumption pattern.
Accurate energy models are required for designing and testing energy aware protocols.
The accuracy of these energy models and their contribution toward energy aware protocol design
depend on the accuracy and availability of sufficient data about power consumption of these devices.
This work contributes to the building of such a power consumption database through a
series of measurements of currently available Wireless Network Interface Cards (WNIC) and Radio
Frequency Identification Devices (RFID). These measurements also help in understanding the
behavior of these technologies at the lower levels of the network stack. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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A hybrid approach to forecasting wind power using Artificial Neural Networks and Numeric Weather PredictionPfeifer, Mark B. 07 1900 (has links)
A methodology to forecast wind power production 24 hours ahead is developed using a
hybrid approach of an artificial neural network (ANN) and numerical weather prediction (NWP).
The methodology is simple and designed to be applicable to any wind farm on the globe, using
publicly available NWP data and basic historical power production data from wind farm.
Notably, no historical wind data from on-farm sensors is required as the 0 hour forecast data is
used to train the ANN. The results are encouraging, with a root-mean-square-error of 0.2267 for
a 24 hour ahead forecast, corresponding to a forecast error standard deviation of 0.23 per unit. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.
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