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A Human-Computer Integrated Approach Towards Content Based Image Retrieval, Phani Nandan Kidambi 2010 Wright State University

A Human-Computer Integrated Approach Towards Content Based Image Retrieval, Phani Nandan Kidambi

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Digital photography technologies permit quick and easy uploading of any image to the web. Millions of images being are uploaded on the World Wide Web every day by a wide range of users. Most of the uploaded images are not readily accessible as they are not organized so as to allow efficient searching, retrieval, and ultimately browsing. Currently major commercial search engines utilize a process known as Annotation Based Image Retrieval (ABIR) to execute search requests focused on retrieving an image. Even though the information sought is an image, the ABIR technique primarily relies on textual information associated with an …


Design Of Hf Forward Transformer Including Harmonic Eddy Current Losses, Dhivya Ammanambakkam Nagarajan 2010 Wright State University

Design Of Hf Forward Transformer Including Harmonic Eddy Current Losses, Dhivya Ammanambakkam Nagarajan

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Pulse Width Modulated (PWM) Forward DC-DC converter is a buck-derived isolated power converter which is used extensively in low power to medium power applications. Satisfactory operation of the transformer utilized in forward converter plays a crucial role in the overall operation of the forward converter. Hence detailed analysis pertaining to design of forward transformer is important. The forward transformer is unique as the magnetizing inductance is not required to store magnetic energy. Additionally, the forward transformer has a tertiary winding, which is required to reset the core and to prevent core saturation. This adds to the complexity of design and …


An Improved Genetic Algorithm For Knapsack Problems, Taskiran, Gamze Kilincli 2010 Wright State University

An Improved Genetic Algorithm For Knapsack Problems, Taskiran, Gamze Kilincli

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In this study, an improved genetic algorithm (GA) is presented to solve the multidimensional 0-1 knapsack problem (MKP). The MKP is a well-known combinatorial optimization problem and has received wide attention from the operations research community for decades. Although recent advances in computing and optimization technologies have made the solution of small and medium size instances possible, this NP-hard problem, in general, still remains one of the challenging problems yet to be solved.

Of the various algorithms developed to solve the MKP, GA seems to be one of the best methods pointed out in the literature. A GA is an …


The Harmonic Distortion Reduction Of Phase-Angle Fired Scrs Feeding A Resistive Load Using Fuzzy Logic, Matthew A. Clark 2010 Wright State University

The Harmonic Distortion Reduction Of Phase-Angle Fired Scrs Feeding A Resistive Load Using Fuzzy Logic, Matthew A. Clark

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High power silicon controlled rectifiers (SCR) are used in the application of infrared radiation testing. A case study has been performed on a department of defense facility utilizing SCRs to transfer electrical energy to thermal energy. The facility is capable of generating up to 5000 °F across large cross-sectional areas, requiring tens of megawatts of power. The combination of high power, unbalanced loads, and SCR switching generate high harmonic disturbances that offer significant challenges for conventional linear control systems. In addition, unbalanced three-phase distribution systems are difficult to model, specifically during switching transients. Fuzzy logic is used to characterize the …


Population Fit Threshold: Fully Automated Signal Map Generation For Baseline Correction In Nmr-Based Metabolomics, Daniel C. Homer 2010 Wright State University

Population Fit Threshold: Fully Automated Signal Map Generation For Baseline Correction In Nmr-Based Metabolomics, Daniel C. Homer

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Baseline correction of NMR-based metabolomic spectra is a key step in data processing to elucidate biomarkers of diseased and toxic states. Automated baseline correction methods often use human-selected parameters. Presented is a method for automated baseline correction using parameters selected from and without manipulation of the spectrum. The focus is on generating an accurate signal map based on the differentiating characteristics of baseline noise and signal. The presented method of signal map generation and baseline correction was developed and tested on 13C and 1H NMR spectra. The spectra were as simple as chemical standards containing less than 25 signal peaks …


Induction Of P53 Dependent Cellular Senescence Through Hdmx Inhibition Or Ypel3 Expression, Kelly Lynn Robbins Miller 2010 Wright State University

Induction Of P53 Dependent Cellular Senescence Through Hdmx Inhibition Or Ypel3 Expression, Kelly Lynn Robbins Miller

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Mutations in p53 that compromise its function have been reported in approximately half of all human cancers (Vousden et al., 2002). The other half of human tumors that retain wild-type p53 have a dysfunctional p53 pathway through other mechanisms (Wade et al., 2009). Activation of p53 leads to cell cycle arrest, DNA repair, apoptosis and senescence, however, the pathway leading to cellular senescence is the focus of this study. Cellular senescence is a process leading to irreversible arrest of cell division. Under normal physiologic conditions, the activity of p53 is kept in check by its negative regulators, Mdm2 and MdmX. …


Development Of An Efficient Super-Resolution Image Reconstruction Algorithm For Implementation On A Hardware Platform, Pestak Thomas C. 2010 Wright State University

Development Of An Efficient Super-Resolution Image Reconstruction Algorithm For Implementation On A Hardware Platform, Pestak Thomas C.

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There is a growing demand from numerous commercial and military applications for images with ever-improving spatial resolution. However, there are resolution-limiting factors inherent in all imaging systems. Decreasing pixel sizes and/or increasing sensor arrays are not always viable. Super-Resolution (SR) Image Reconstruction is an image processing technique that restores a high-resolution (HR) image from a series of low-resolution (LR) images of a particular scene. Recently, there has been extensive research on robust SR algorithms used for post-processing. The goal of this thesis is to explore the current SR research and design computationally efficient SR algorithms for real-time processing based on …


A Direction Finding System Using Log Periodic Dipole Antennas In A Sparsely Sampled Linear Array, Jonathan Andrew Weldon 2010 Wright State University

A Direction Finding System Using Log Periodic Dipole Antennas In A Sparsely Sampled Linear Array, Jonathan Andrew Weldon

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This thesis explores the use of wide band log periodic dipole array (LPDA) antennas in direction finding systems. A wide band log periodic antenna will be constructed and tested to ensure hardware capability. A novel approach utilizing non-uniform spacing in a linear array will be used to improve the spatial resolution of the direction finding system. These specialized linear arrays are known as minimum redundancy or non-redundant linear arrays.


Frequency Domain Processing Based Chaos Communication For Cognitive Radio, Daniel Y. Sundersingh 2010 Wright State University

Frequency Domain Processing Based Chaos Communication For Cognitive Radio, Daniel Y. Sundersingh

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Chaotic systems are deterministic non-linear dynamical systems which have intrinsic properties such as: irregularity, aperiodicity, and are impossible to predict over long periods of time. Cognitive radio on the other hand, has emerged recently as a powerful means to tackle the spectrum congestion problem. The goal of this thesis is to combine the benefits of the chaos communication system with the cognitive radio to create a robust, highly secure, flexible chaotic cognitive radio system. We first begin with a short survey of chaotic communication and cognitive radio technology. Then we compare chaotic waveforms to other conventional PN sequences and show …


A Study Of Evolvable Hardware Adaptive Oscillators For Augmentation Of Flapping-Wing Micro Air Vehicle Altitude Control, Bharath Venugopal Chengappa 2010 Wright State University

A Study Of Evolvable Hardware Adaptive Oscillators For Augmentation Of Flapping-Wing Micro Air Vehicle Altitude Control, Bharath Venugopal Chengappa

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The control of insect-sized flapping-wing micro air vehicles is fraught with difficulties. Even when adequate control laws are known, limits on computational precision and floating-point processing can render it difficult to field implementations that provide sufficiently accurate and precise vehicle body placement and pose. Augmentation of an existing altitude controller with an Evolvable Adaptive Hardware (EAH) oscillator has been proposed as a means for an on-board altitude controller to correct control precision and accuracy difficulties during normal flight. This thesis examines a range of setting of the internal learning algorithms for the EAH oscillator and provides empirical evidence about which …


Cytochrome C Oxidase From Rhodobacter Sphaeroides: Oligomeric Structure In The Phospholipid Bilayer And The Structural And Functional Effects Of A C-Terminal Truncation In Subunit Iii, Teresa L. Cvetkov 2010 Wright State University

Cytochrome C Oxidase From Rhodobacter Sphaeroides: Oligomeric Structure In The Phospholipid Bilayer And The Structural And Functional Effects Of A C-Terminal Truncation In Subunit Iii, Teresa L. Cvetkov

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Cytochrome c oxidase (COX) of the mitochondrial electron transport chain catalyzes the reduction of oxygen to water while concomitantly translocating protons across the inner mitochondrial membrane. This two part dissertation is a structural and functional investigation of COX using the bacterial model system from Rhodobacter sphaeroides (R.sph.).

First, the oligomeric structure of R.sph. COX within the lipid bilayer was investigated using discontinuous sucrose gradient ultracentrifugation. Utilizing this technique, liposomes containing R.sph. COX (pCOV) were separated from liposomes lacking enzyme (COV). The net buffering capacity and degree of light scattering per COX molecule were reduced in pCOVs, making them well suited …


Analysis Of Amputee Gait Using Virtual Reality Rehabilitation Techniques, Maurissa S. D'Angelo 2010 Wright State University

Analysis Of Amputee Gait Using Virtual Reality Rehabilitation Techniques, Maurissa S. D'Angelo

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This research shows promise in becoming a standard practice for long term amputee rehabilitation. Exceptional rehabilitation is not universally available to all disabled individuals due to circumstances which limit patient care such as a limited number of trained personnel, limited access to therapy in remote areas, limited patient feedback, limited visits under insurance policies and differing expertise of personnel. Providing real-time, objective feedback will help to continuously improve the quality of life of amputee individuals and provide standardized baseline techniques. The research described in this dissertation expands the use of virtual reality systems to amputee rehabilitation. A virtual reality system …


Wideband, High Data Rate Ku-Band Modulator Driver Amplifier For High Reliability Spaceborne Applications, Jeremy D. Gassmann 2010 Wright State University

Wideband, High Data Rate Ku-Band Modulator Driver Amplifier For High Reliability Spaceborne Applications, Jeremy D. Gassmann

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The increased demand for high resolution satellite imagery for government, military, and commercial applications is driving the need for high data rate, millimeter-wave transmission systems to relay imagery information to a ground-based end user. An important aspect of this system which interfaces digital information to the RF domain is the modulator driver. The current trend in miniaturization of electronics leaves systems more vulnerable to single-event radiation effects in spaceborne applications. In an effort to overcome this deficiency, a wideband, high data rate modulator driver circuit has been designed, built, and tested using only high reliability space rated electronic components. To …


Privacy-Preserving Attribute-Based Access Control In A Grid, Sang Mork Park 2010 Wright State University

Privacy-Preserving Attribute-Based Access Control In A Grid, Sang Mork Park

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A Grid community is composed of diverse stake holders, such as data resource providers, computing resource providers, service providers, and the users of the resources and services. In traditional security systems for Grids, most of the authentication and authorization mechanisms are based on the user's identity or the user's classification information. If the authorization mechanism is based on the user's identity, fine-grained access control policies can be implemented but the scalability of the security system would be limited. If the authorization mechanism is based on the user's classification, the scalability can be improved but the fine-grained access control policies may …


Ab Initio Simulations Of Hydrogen And Lithium Adsorption On Silicene, Tim H. Osborn 2010 Wright State University

Ab Initio Simulations Of Hydrogen And Lithium Adsorption On Silicene, Tim H. Osborn

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The energies and temperature-dependent dynamics of hydrogen and lithium chemisorption on a silicon nanosheet, called silicene, were studied using density functional theory and molecular-dynamics (MD) simulations. Silicene has a buckled honeycomb structure, and has been fabricated as suspended monolayer sheets and nanoribbons in recent experiments. We calculated the adsorption energies of hydrogen and lithium on silicene for different adsorption ratios between 3.1% and 100%. The studies will clarify the characteristics of these novel and promising nanomaterials, and pave the way for their applications.

For Hydrogen, the adsorption energy had a maximum of 3.01 eV/H for complete hydrogenation, and decreased by …


A Critical Assessment Of The High Cycle Bending Fatigue Behavior Of Boron-Modified Ti-6al-4v, Casey M. Holycross 2010 Wright State University

A Critical Assessment Of The High Cycle Bending Fatigue Behavior Of Boron-Modified Ti-6al-4v, Casey M. Holycross

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Boron-modified Ti-6Al-4V alloys have shown increased performance in mechanical properties over unmodified alloys and are currently of interest for use in turbine engine applications. These alloys offer up to 40% increase in ultimate tensile strength, up to 30% increase in stiffness, and favorable damage characteristics while maintaining a ductility greater than 10%. These attractive properties are attributed to small additions of boron that refine the microstructure and form strong and stiff TiB whiskers. Previous research has found that these modified alloys compare favorably in fatigue. Samples machined from a powder-metallurgy forging with nominal composition Ti-6Al-4V-1B, were tested in fully-reversed bending …


Impact Of Culture And Age On The Use Of Social Networking Websites, Ramya Reddy Ponnavolu 2010 Wright State University

Impact Of Culture And Age On The Use Of Social Networking Websites, Ramya Reddy Ponnavolu

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Social networking websites have become very popular amongst people of all ages in recent times. These websites have brought into existence a new form of data - 'User generated content'. Companies everywhere have begun to identify the potential of these sites and have commenced efforts to take advantage of the profitable opportunities available. In spite of all this, it is reasonable to say that the latent possibilities in social networking sites are yet to be fully explored. This is due to the fact that the technology is still young and research on its potential is still ongoing. The current research …


Prognosis: A Wearable System For Health Monitoring Of People At Risk, Alexandros A. Pantelopoulos 2010 Wright State University

Prognosis: A Wearable System For Health Monitoring Of People At Risk, Alexandros A. Pantelopoulos

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Wearable Health Monitoring Systems (WHMS) have drawn a lot of attention from the research community and the industry during the last decade. The development of such systems has been motivated mainly by increasing healthcare costs and by the fact that the world population is ageing. In addition to that, RandD in WHMS has been propelled by recent technological advances in miniature bio-sensing devices, smart textiles, microelectronics and wireless communications techniques. These portable health systems can comprise various types of small physiological sensors, which enable continuous monitoring of a variety of human vital signs and other physiological parameters such as heart …


Charaterization Of Chlorpyrifos Toxicity On The Pancreatic Beta Cell Line Rinm5f, Zhongyu Yan 2010 Wright State University

Charaterization Of Chlorpyrifos Toxicity On The Pancreatic Beta Cell Line Rinm5f, Zhongyu Yan

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Chlorpyrifos (CPF) is a well-known organophosphate (OP) insecticide that inhibits acetylcholinesterase (AChE). Organophosphates have been shown to induce hyperglycemia in both humans and animals that cannot be explained by AChE inhibition alone. Pancreatic β-cells are responsible for secreting insulin and playing a fundamental role in glucose homeostasis. The aim of this research was to investigate CPF toxicity on the insulin secreting β-cell line RINm5f (RIN). In the first part of this dissertation, we determined that cytotoxic concentrations of CPF between 50 µM and 200 µM induced a dose-dependent increase in RIN cell apoptotic and necrotic death (p<0.05). Lower doses, i.e., 5-25 µM did not induce apoptosis or necrosis. In further mechanistic studies, inhibitors of c-Jun N-terminal kinase (JNK) and P38 pathways, i.e., SP600125 and SB202190, successfully attenuated CPF-induced apoptosis (p<0.05), suggesting cell death is mediated by JNK and/or p38. In addition, N-Acetyl-L-cysteine (NAC), an antioxidant, inhibited apoptosis suggesting that oxidative stress is also involved in RIN cell death. In the second part of this dissertation, low dose CPF's effects on insulin synthesis and secretion was studied. Our results showed that RIN cells treated with CPF for 4 hr exhibited a dose-dependent decrease in insulin secretion in response to stimulation by 50 mM potassium (p<0.05). Insulin secretion stimulated by 25 mM glucose also showed significant decreases upon incubation with various doses of CPF (p<0.05). Insulin synthesis involves proteolytic cleavage of proinsulin at two specific sites. The enzymes responsible for promoting proinsulin cleavage, i.e, prohormone convertase (PC) 1/3 and 2 (PC2), contain a serine hydrolase catalytic triad, His-Asp-Ser, similar to AChE. CPF modification of PC enzymes similar to AChE, could potentially interrupt the conversion of proinsulin to insulin and disrupt insulin secretion. PC2 enzyme activity was significantly inhibited by CPF at concentrations as low as 10 µM (p<0.01). RIN cells, for the first time, were found to secrete proinsulin was through a constitutive instead of a regulated pathway. In summary, our results show that CPF not only exerts a direct cytotoxic effect at concentrations above 50 µM, but also significantly impairs insulin secretion at lower doses. Low dose CPF could potentially affect endocrine function in vivo by inhibiting the proinsulin processing enzyme PC2.


Fabrication Of Zinc Oxide Thin Films For Renewable Energy And Sensor Applications, Theresa Y. Hill 2010 Wright State University

Fabrication Of Zinc Oxide Thin Films For Renewable Energy And Sensor Applications, Theresa Y. Hill

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Progress in commercializing renewable energy technologies is being advanced by developments in Zinc Oxide material science. The photovoltaic cell, for example, generates electricity by receiving solar energy into the cell, generating electrons, and simultaneously transporting electrical charge out of the cell. Metals are capable of removing electrical charge but block transmission of sunshine. Glass and plastics are capable of transmitting sunshine but block the removal of electrical charge. Therefore an exterior layer that is both optically transparent and electrically conductive is desirable. Transparent conductive oxides (TCOs) are the ideal material for such applications since they are capable of both functions. …


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