Digital Commons Network^™

Effect Of Material Anomalies On Fatigue Life Of Turbine Disks, Jace A. Carter

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There is an economic need to extend the fatigue life of turbine engine rotor disks. The probability of failure during the operation life must be quantified as components remain in service beyond their traditional safe-life limit. Fracture mechanics based probabilistic methods are utilized to predict the probability of failure of components containing manufacturing and fatigue anomalies. Total fatigue life is defined in terms of crack initiation and propagation phases. A micromechanical initiation model uses material properties at the micro-scale to characterize the initiation phase, while short and long fatigue-crack growth models predict the crack propagation phase. A Monte Carlo simulation …

Selective Automatic Image Feature Detection, Aijing Wang

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To allow automatic assessment of computed tomography (CT) images of long bones, the identification of the location of regions of interest is important. The distance between the distal and proximal styloids may act as reference points for bone length; however, the locations of the distal and proximal growth plates represent further important reference features. The current methods to locate these feature positions are manual. In this project, we attempt to find these feature positions automatically.

A CT data set was split into two subsets, a development set, and a validation set. We first extracted basic information from the stack and …

Semi-Supervised Contrafold For Rna Secondary Structure Prediction: A Maximum Entropy Approach, Jianping Feng

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A novel probabilistic discriminative model based on conditional random fields, CONTRAfold, has recently been proposed for single sequence RNA secondary structure prediction. By incorporating most of the features which closely mirror the local interaction terms of thermodynamics-based models, the CONTRAfold model has outperformed both probabilistic and physics-based techniques, and received the highest single sequence prediction accuracies. CONTRAfold, like most other RNA secondary structure prediction techniques, requires a collection of RNA sequences with known secondary structure to serve as training data for the algorithm. Manual annotation of RNA sequences is both expensive and time-consuming, and there remains a great deal more …

Niyama Based Taper Optimizations In Steel Alloy Castings, Daniel A. Gorsky

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In the casting process, regions of shrinkage porosity can be reduced or eliminated through the implementation of taper, or small angled additions of mass on the boundaries of the part design, before risers are placed on the casting. Taper supplements the effect of risers so that a smaller riser volume is necessary to make a casting sound. Typically, taper is determined for a casting by using industry guidelines that were developed for simple two-dimensional simplifications of a complex casting. There is no accepted method of defining taper directly on part geometry aside from using expert opinions to make final decisions …

Process Sequencing For Fatigue Life Extension Of Large Scale Laser Peened Components, Thomas Joshua Spradlin

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Mechanical surface enhancement techniques have been used to successfully increase the fatigue life of metallic components. These techniques impart compressive surface residual stresses that reduce the tensile stresses experienced during service loading. Laser Peening (LP) is a surface enhancement technique that uses high intensity, short duration laser pulses to create plastic shockwaves in metallic components. Experimental investigations and limited simulation studies have been conducted to determine the effects on the fatigue life of simple coupons when key LP parameters are varied. Used primarily in the aerospace and biomedical engineering fields, LP has been limited to industries that can afford its …

Optimizing Memory Cost With Loop Transformations, Hailong Shi

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Embedded systems are usually constrained in terms of timing, power, and memory. Many embedded applications, especially in the multi-media and telecom domains, are inherently data dominant. These embedded DSP applications usually exhibit intensive computations in the form of multi-level loops. The performance of these embedded DSP applications mainly depends on the code quality of the loops and the memory hierarchy design. During the design phase of the embedded system, it is important to estimate the overall storage requirement to guide the memory system design and take advantage of the memory system by program transformations and loop transformations.

Loop transformations including …

Methylmercury In Mosquitoes: Impact Of A Large Coal-Fired Power Station In Central Ohio, Matthew J. Konkler

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Emissions from coal-fired utilities are the major anthropogenic source of mercury (Hg) to the atmosphere. Because emitted Hg may be deposited near the source, there are concerns on levels of toxic monomethylmercury (MeHg) in local biota. We investigated the potential impact of a large Hg-emitting (> 500 kg Hg y-1) coal-fired power station on MeHg levels in mosquitoes near the Conesville power station in central Ohio. Mosquitoes were sampled with CO2-baited traps at 23 locations within a 60 km radius of the utility and at three reference sites distant from Hg combustion sources. MeHg in mosquitoes within a 30-km radius …

Discretion Without Choice: Sexual Offender Legislation And Judicial Discretion, Jonathan C. Varhola

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In a historically recent development, sex offenders have arguably become a focal point of attention in discourses surrounding sexuality, childhood, and crime. Much research has been accomplished regarding the treatment and recidivism of such offenders, as well as consequences of sex offender legislation and policy initiatives. However, little research has been done regarding specifically the discretion of criminal justice agency professionals involved in the day-to-day handling of these types of cases. This study focused on the effects of such policies on judicial discretion, as measured by sentencing outcomes. Data was collected from publicly available internet sexual offender registries and county …

Role Of Hyperglycemia And Aldosterone On Renal Ace2 And Albuminuria In Db/Db Mice, Harshita Chodavarapu

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Diabetic nephropathy (DN) is one of the microvascular complications of type II diabetes and a leading cause for the development of end stage renal disease. Renin angiotensin system (RAS) plays a pivotal role in the development and progression of diabetic nephropathy. Hyperglycemia activates RAS and increases tissue and circulating levels of angiotensin II (Ang II) and aldosterone. A new component of RAS, angiotensin converting enzyme 2 (ACE2), has been shown to be renoprotective in early stages of diabetes. The aim of this study is to test the hypothesis that strict glycemic control using rosiglitazone or treatment with mineralocorticoid receptor (MR) …

Near Equilibrium Dissolution Of Calcite Using A Flow-Through Reactor (Ftr), Michael Mante

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In mineral dissolution reactions, surface morphologies play important roles particularly in near equilibrium fluids where generation of new sites of reactivity (e.g., pit nuclei) is thermodynamically disfavored. Following CO₂ injection in geologic formations, dissolution of primary carbonate minerals and crack-sealing cements will occur. The impact of these reactions on fluid chemistry requires better understanding of the reaction kinetics of major minerals at close-to-equilibrium conditions. Initial investigations have focused on quantifying calcite dissolution using short residence time (~ 10 min) flow through reactors to obtain dissolution rates at 60°C, pH = 8.33 and Pco₂ = 3.8 x 10^{-4 …}

A Comparison Of Work-Specific And General Personality Measures As Predictors Of Ocbs And Cwbs In China And The United States, Qiang Wang

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Previous studies on frame-of-reference effects have focused on domain-specific personality measures as predictors of performance in North America. The current study expands on this research by comparing work-specific and general personality as predictors of CWBs and OCBs in an East Asian culture (i.e., China). Consistent with the literature on frame-of-reference effects in personality assessment, I found that three Big Five personality dimensions, including agreeableness, conscientiousness, and emotional stability, were significantly related with OCBs and CWBs. Also, use of a frame of reference that is conceptually relevant to the criterion led to increased validity as a result of the decrement in …

Multipurpose Map Designs For Gps Surface-Vehicle Navigation: Spatial Knowledge And Advisory Functions, Caitlan A. Rizzardo

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Current car navigation systems primarily utilize track-up maps with spatial turn arrows, which facilitate turn decision-making but do not facilitate acquisition of spatial knowledge of the region. North-up maps do facilitate acquisition of regional spatial knowledge, however, these displays sometimes have arrows heading in directions misaligned with a driver's forward view, such as when the car is heading south. Drivers have difficulty making turn decisions in these misaligned maps because of stimulus-response reversals (Chan and Chan, 2005; Levine, 1982; Levine, Marchon and Hanley, 1984; Montello, 2010). A new display was designed using a fixed orientation north-up map and added a …

An Exploratory Study Of Mixed-Width Aisle Layouts For Order Picking In Distribution Centers, Corinne H. Mowrey

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Order picking is arguably the most expensive operational activity for a distribution center (DC), constituting upwards of 50% of total operating costs. Designing an optimum order picking system (OPS) for a DC depends on several system parameters, such as aisle layout, storage system configuration, storage policy, picking method, and picking strategy. From an aisle layout standpoint, traditional DCs utilize either entirely wide or entirely narrow aisles in their picking systems. Wide aisles allow pickers to pass each other, reducing blocking and requiring fewer pickers. However, the space required for wide-aisle systems is high. Narrow aisles utilize less space than wide …

Developing A Word Fragment Completion Task For Measuring Trait Aggression, Steven Khazon

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The goal of this paper was to develop a test that uses the implicit processing style to assess aggression. This paper begins by reviewing current aggression theories and how aggression is assessed. Next it discusses the implicit and explicit processing styles and how scholars have used these methods of information processing to create psychological assessments. Afterwards, it presents a new indirect test of trait aggression that is based on the word fragment completion task and attempts to evaluate its validity in three experiments. In Study 1, psychometric methods are used to derive a 9-item trait aggression scale and initial support …

Synaptic Contact Localization In Three Dimensional Space Using A Center Distance Algorithm, Benjamin D. Ausdenmoore

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Spatial distribution of synaptic inputs on the dendritic tree of a neuron can have significant influence on neuronal function. Consequently, accurate anatomical reconstructions of neuron morphology and synaptic localization are critical when modeling and predicting physiological responses of individual neurons. Historically, generation of three-dimensional (3D) neuronal reconstructions together with comprehensive mapping of synaptic inputs has been an extensive task requiring manual identification of putative synaptic contacts directly from tissue samples or digital images. Recent developments in neuronal tracing software applications have improved the speed and accuracy of 3D reconstructions, but localization of synaptic sites through the use of pre- and/or …

Impact Of Insulin Resistance On Behavioral And Neurochemical Deficits In Db/Db Mice, Ajaykumar Narayan Sharma

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There is a high comorbidity of type-2 diabetes and neuropsychiatric disorders. However, there is paucity of preclinical research to study this phenomenon. The validity of the db/db mouse as an animal model to study type-2 diabetes and related macrovascular and microvascular complications is well established. The first part of this dissertation was designed to investigate comprehensively the db/db mouse behavior as preclinical evidence of type-2 diabetes related major neurobehavioral complications. Juvenile (5-6 weeks) and adult (10-11 weeks) db/db mice were screened for behavioral depression in forced swim test (FST), psychosis-like symptoms using pre-pulse inhibition (PPI) test, anxiety behavior employing elevated …

Towards Optimal Resource Provisioning For Running Mapreduce Programs In Public Clouds, Fengguang Tian

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Running MapReduce programs in the public cloud introduces the important problem: how to optimize resource provisioning to minimize the financial charge for a specific job? In this thesis, We study the whole process of MapReduce processing and build up a cost function that explicitly models the relationship between the amount of input data, the available system resources (Map and Reduce slots), and the complexity of the Reduce function for the target MapReduce job. The model parameters can be learned from test runs with a small number of nodes on a small amount of data. Based on this cost model, we …

Synthesis Of Isatin Derivatives Used For The Inhibition Of Pro-Apoptotic Jurkat T Cells, Charles Michael Clay

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A range of substituted 1H-indole-2,3-diones (isatins) was synthesized to assess their capability to inhibit caspases and prevent apoptosis in Jurkat T cells. The key steps in the synthesis of such molecules involved electrophilic substitution of the C-5 position of the isatin nucleus (if necessary), N-alkylation, Wolff-Kishner reduction of the C-3 carbonyl group and finally, Knoevenagel condensation. The design and synthesis of such potential inhibitors was guided by SAR studies of peptide based inhibitors such as "Q-VD-O-Ph", as well as small-molecule inhibitors based upon the isatins scaffold. Previously, 3-(2,6-difluorobenzylidene)-5-nitroindolin-2-one has been shown to inhibit apoptosis in human Jurkat T cells at …

Lithium-Ion Battery Anodes Of Randomly Dispersed Carbon Nanotubes, Nanofibers, And Tin-Oxide Nanoparticles, Gerard Klint Simon

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Lithium-ion battery anodes with a nanostructure of randomly dispersed carbon nanofibers (CNFs), carbon nanotubes (CNTs), and nanoparticles of tin-oxide or silicon were fabricated and tested in order to develop high capacity, easily manufactured anodes. In these anodes, a mesh of CNTs and CNFs form a conductive network within which the nanoparticles of tin-oxide are suspended. The CNT network directs electron flow to and from the nanoparticles while accommodating their volume changes. The CNFs were intended to aid electron transport by serving as conduction channels between the CNTs and the current collector. Secondarily, the CNFs reinforce the physical structure of the …

Graphene Based Rf/Microwave Impedance Sensing And Low Loss Conductor For Rf Applications, Iramnaaz Iramnaaz

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Biosensors are becoming more popular recently and expanding due to their broad applications in detecting disease and infectious agents, monitoring of environmental toxins, etc. Recognition and quantification of biochemical molecules and molecular interactions present great challenges in biosensing [38]. Impedance sensing at radio frequency (RF) /microwave frequency becomes very attractive as bio-molecules exhibits large distinct dielectric properties, and also because the ionic conductivity of water in most physiological systems is greatly diminished. For example, it has been reported that tumoral cells exhibits large value of electrical conductivity and permittivity which can result in significant variation of the impedance when compared …

3-D Model Characterization And Identification From Intrinsic Landmarks, John L. Camp

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A method to automatically characterize and identify 3-D range scans based on intrinsic landmarks is presented. Intrinsic landmarks represent locally unique, intrinsic properties of a scanned surface, regardless of scale or rotation. The number, location, and characteristics of landmarks are used to characterize the scanned models. This method contains a selection process to identify stable, intrinsic landmarks for range scans as well as the identification of those scans. The selection process requires no user interaction or surface assumptions. It uses the principal curvatures at the range points to select the landmarks. First, a large number of landmarks are generated by …

Analysis Of Archived Dried Blood Spots By Mass Spectrometry For Vitamin D And Real-Time Pcr For Its Enzymes And Receptor, Amod N. Joshi

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Vitamin D is an essential micronutrient required for maintenance of the skeletal system and its deficiency leads to diminished availability of calcium for maintaining bone mineralization. Vitamin D deficiency (VDD) during pregnancy and/or in early infancy can lead to rickets and a fragile bone state resulting in fractures with minimal forces. Such multiple unexplained fractures (MUF) present in infants at less than 6 months of age are often misdiagnosed as cases of child abuse. Therefore, it is important to evaluate the status of vitamin D in early infancy. The analysis of dried blood spots (DBS) provides a unique screening method …

Performance Analysis Of Radar Waveforms For Congested Spectrums, Shaun W. Frost

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With more users populating the RF spectrum and hence less available contiguous bandwidth, radar and communication waveforms are slowly forced to become more efficient at using their available frequencies. Two scenarios are considered: operation in a colored interference environment and operation in discontiguous spectral bands. Unconstrained algorithms for designing transmit waveforms and receive filters are evaluated, wherein varying a convex weight trades performance between spectral flatness and side lobe levels. An empirical study provides performance bounds for constrained radar waveform designs for an instantiation of the interference spectrum.

Closed-form predictions for integrated sidelobe ratio (ISLR) and peak-to-sidelobe ratio (PSLR) for …

Cetyltrimethylammonium Halide-Coated Electrodes For The Detection Of Dopamine In The Presence Of Interferents, Amber J. Yeary

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Specially constructed carbon paste electrodes were coated with 10 mM cetyltrimethylammonium halide (CTAX) solutions, bromide and chloride being the counter anions. These surfactant modified electrodes were used to detect the catecholamine neurotransmitter dopamine using cyclic voltammetry. The coated electrodes gave reproducible quasi-reversible behavior for the analyte dopamine over a range of concentrations from 1 mM to 200 mM. When combined in solution with common interferents ascorbic acid (1 mM) and uric acid (300 μM), all cathodic and anodic current peaks maintained resolution at the biological pH of 7.4. When the coating solutions were below the critical micelle concentration (0.5 mM), …

Functional Metabolomics' Enhances Assessment Of Tissue Dysfunction As Demonstrated In A Rat Model Of Sub-Acute D-Serine Exposure, Isaie Sibomana

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We describe a methodology that combines urinary metabolomics with a tissue-specific stressor administration to enhance assessment of tissue function. Kidney function in rats was mildly compromised with a sub-acute dose of D-serine and stressed with furosemide. NMR-based metabolomics analyses showed no detectable effects due to D-serine alone; but furosemide or D-serine + furosemide groups, classified separately from each other, and from control. Furosemide alone caused a ca. 2-fold increase in glucose, lactate, choline, and a 30% decrease in TCA intermediates (p≤0.05). D-serine suppressed these effects and produced a 1.7-fold increase in a p-phenolic acid-derivative of tyrosine (PAdY) relative to control …

Distribution Of Cellular Interferon Beta (Ifn-Β) In Murine Fibroblast Cell Lines Upon Infection Of Hsv-1, Rachael E. Curtis

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The hypothesis for this study was: IFN-β expression differs between murine fibroblasts (A2R1 and L929) of different mouse strains upon infection of HSV-1. Fluorescent microscopy was used to examine localization of IFN-β in the different murine fibroblast and keratinocyte cell lines after 6 hours of infection with herpes simplex virus type-1 (HSV-1). Because keratinocytes cell lines HEL-30 and PAM-212 grew in clusters, staining patterns in individual cells could not be determined. A notable difference in localization of IFN-β immune staining was seen between the two cell lines when infected with HSV-1. The A2R1 cell line showed perinuclear (PN) localization, while …

Multi-Locus Evidence Of A Late Pleistocene Divergence And Sex-Biased Dispersal In The North American Wood Duck (Aix Sponsa), Christopher T. Bigley

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The Pleistocene was characterized by fluctuations in climate causing repeated advances and retreats of glacial ice. The advancing ice sheets caused habitat fragmentation which initiated population divergence and speciation events between eastern and western avian populations within northern temperate forests. Based on mitochondrial DNA (mtDNA) control region sequences, North American Wood Duck (Aix sponsa) populations fit this model of divergence. However, mtDNA is maternally inherited, and thus may not reflect the genomic history of this species, because of male biased-dispersal, selection, or stochastic lineage sorting. To test the "Late Pleistocene divergence" hypothesis, I sequenced 11 independent nuclear introns (nuDNA) for …

Targeted Knockdown Of Amp-Activated Protein Kinase Alpha 1 And Alpha 2 Catalytic Subunits, Larissa J. Tangeman

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AMP-activated protein kinase (AMPK) regulates cellular metabolism and promotes ATP production when energy is depleted. Evidence suggests that AMPK may be involved in oxygen sensing by carotid body cells, which are responsible for regulating the breathing rate to maintain proper blood oxygen levels. There are two isoforms of the catalytic alpha subunit, AMPKalpha1 and AMPKalpha2, which could be involved in oxygen sensing. Here, the production of a short hairpin RNA (shRNA) targeting both catalytic isoforms of AMPK in human, mouse, and rat is described. The shRNA causes significant knockdown of both isoforms of AMPK alpha in mouse and human cells …

Frequency Diverse Array Receiver Architectures, Aaron M. Jones

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Typical radar systems are limited to energy distribution characteristics that are range independent. However, operators are generally interested in obtaining information at particular ranges and discarding elsewhere. It seems appropriate then to attempt to put energy solely at the range(s) of interest, thus minimizing exposure to clutter, jammers and other range-dependent interferences sources. The frequency diverse array (FDA) can provide a mechanism to achieve range-dependent beamforming and the spatial energy distribution properties are investigated on transmit and receive for different architectures herein.

While simplified FDA receive architectures have been explored, they exclude the return signals from transmitters that are not …

Dynamic Footed With Clock Overlapping And Load Balancing In Multiple Paths For Noise Tolerance In Dynamic Cmos Circuits, Ramadan U. Buzakuk

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Dynamic CMOS circuits are used in microprocessors as well as in circuits that require high speed and small areas. Dynamic CMOS circuits have many advantages but are not robust in noise tolerance in comparison with the legacy static CMOS circuits. In this thesis several noise tolerance techniques that can be implemented with Dynamic CMOS circuits for robust noise tolerance are studied. A dynamic footed with clock overlapping technique integrated with a load balancing multiple-path transistor sizing algorithm for optimizing performance of noise tolerance and speed while in consideration of process variations is presented. Using the 2-bit weighted binary-to-thermometric converter implemented …