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  • 1. Duning, Solomon 3D Textile PMC Damage Evolution: Effects of Fiber Volume Fraction and Morphology Variation

    Master of Science (M.S.), University of Dayton, 2016, Mechanical Engineering

    3D textile polymer matrix composites (PMC) exhibit geometric and material state variances due to differences in manufacturing processes and a variety of other factors. Developing a more thorough understanding of these strength and damage variations is a vital aspect of generating an accurate predictive model for the material response of a 3D textile PMC. This work entails both experimental and modeling efforts in order to gain a more thorough understanding of how tow level geometric variations relate to damage evolution in a 3D textile PMC. A 3D orthogonal weave textile is imaged utilizing an X-Ray micro-CT to examine the fiber volume fraction and fiber path distributions within the composite. Additionally, damage evolution is observed at different load steps and CT images are utilized for Digital Volume Correlation analysis. Modeling efforts are primarily focused on tow morphology simulations within the software package- Virtual Textile Morphology Suite (VTMS). Damage evolution analysis on the VTMS models are performed using an advanced Regularized eXtended Finite Element Method (RX-FEM) within the Air Force Research Laboratory developed B-Spline Analysis Method (BSAM) program. Local fiber volume fraction variation in the specimens is examined through serially sectioned images obtained using Robo-Met 3D. Fiber volume fraction distributions are compared to VTMS predictions and VTMS predictions are modified to reflect experimental values. The effect of these local fiber volume fraction distributions on damage evolution in the composite are examined through experimentation and modeling efforts.

    Committee: Margaret Pinnell Ph.D. (Advisor); David Mollenhauer Ph.D. (Committee Member); Tom Whitney Ph.D. (Committee Member) Subjects: Engineering; Materials Science; Mechanical Engineering; Mechanics
  • 2. Atluri, Lava Kumar Design Automation Flow using Library Adaptation for Variation Aware Logic Synthesis

    MS, University of Cincinnati, 2014, Engineering and Applied Science: Computer Engineering

    As semiconductor technology reaches to nanometer scale, the impact of process uncertainties are increasing, leading to performance and power loss, and consequently reducing the yield. These process parameter variations necessitate the use of suitable variation-aware design techniques. There are some architecture level, circuit level, and post silicon techniques with certain overheads to reduce the effect of such variations. Along with good design techniques, variation-aware analysis plays a major role in determining the efficacy of variation tolerant design. Conventional way of min-max static timing analysis is no more a reliable option; we need to use Statistical Static Timing Analysis (SSTA). Although various techniques for variation tolerant design have been proposed, no major emphasis was given to the initial design phases of the ASIC design flow. In this work, we focused on logic synthesis stage to nullify the effects of process variations. For that, we proposed a novel technique called Library Adaptation for Variation Aware (LAVA) technique and automated the flow for the creation of process variation tolerant design. In LAVA technique a new approach is used to create variation aware libraries by re-characterization of existing libraries and new variation tolerant standard cells are created on demand. This work proposes a design methodology from RTL to GDSII that incorporates LAVA technique at logic synthesis stage for creating variation tolerant design with negligible overhead. The primary goal of our methodology is to capture the statistical aspects of variation from transistor-level of abstraction into gate-level i.e., standard cell library. This newly created variation-aware standard cell library is provided to the existing logic synthesis tool to select the better design at higher level of design cycle, thus making the design more robust to process variations. We have used accurate SSTA using PrimeTime VX by providing variation aware libraries (open full item for complete abstract)

    Committee: Ranganadha Vemuri Ph.D. (Committee Chair); Wen Ben Jone Ph.D. (Committee Member); Carla Purdy Ph.D. (Committee Member) Subjects: Computer Engineering
  • 3. Sosnoskie, Lynn Investigations in weed biology: studies at the plant, population, and community levels

    Doctor of Philosophy, The Ohio State University, 2005, Horticulture and Crop Science

    Studies were conducted at the plant, population, and community level to address questions concerning (1) seed germination in Alliaria petiolata (2) weed community composition and structure in response to tillage, rotation and herbicide, and (3) variation in Abutilon theophrasti. Alliaria petiolata seeds are dormant at maturity, requiring approximately 90 to 105 days cold-moist stratification at 4 to 5 °C for germination to occur. Mechanically scarified, and H2O2 and H2SO4 treated seeds germinated within 35 days when GA3 was applied exogenously. The composition of the weed-seedbank community was characterized 35 years after the implementation of a long-term study involving cropping sequence (continuous corn, corn-soybean, corn-oat-hay) and tillage system (conventional-, minimum-, and no-tillage). Values of S, J, and H' recorded for all combinations of the three-crop sequence were typically greater than the values of S, J, and H' reported for either the one and two-crop rotations. As the intensity of soil disturbance decreased, values for S increased. Mean germinable weed seed density was greatest in the no-tillage treatments across rotations and years. Results suggest that the weed seed community in a corn-oat-hay rotational system differs in structure and composition from communities associated with continuous corn and corn-soybean systems. There is concern that the widespread use of genetically-modified glyphosate-tolerant crops (GTCs) will alter agricultural weed community dynamics with respect to glyphosate-tolerance and emergence phenology. Species associated with individual tillage and rotation treatments were not different from species recorded in the same plots prior to the exclusive use of GTCs and glyphosate, suggesting that significant changes in weed community composition and structure have not occurred. Abutilon theophrasti is a noxious weed in modern row-crop agriculture. This study characterized the morphological, phonological, and genetic variation ve (open full item for complete abstract)

    Committee: John Cardina (Advisor) Subjects: Agriculture, Agronomy
  • 4. Ramos-Pellicia, Michelle Language contact and dialect contact: cross-generational phonological variation in a Puerto Rican community in the midwest of the United States

    Doctor of Philosophy, The Ohio State University, 2004, Linguistics

    This study describes phonological variation in a variety of Spanish found in Lorain, Ohio, considering the dynamics of interaction of two minority dialects, Lorain Puerto Rican Spanish (henceforth LPRS) and Mexican American Spanish (hereafter MAS), in the context of American English (henceforth AE) as a majority language. This work examines five variables (raising of /e/ and /o/, and the realization of an affricate, /r/, and /b/) across three LPRS generations. This project also explores the phonology of rural Island Puerto Rican Spanish (hereafter IPRS) transported to Lorain to determine if LPRS and IPRS display similar or different patterns of use of the variables. One hundred four people representing the Puerto Ricans, Mexicans and AE speakers of Lorain and the Puerto Ricans of the island were recorded. These groups were subdivided by generation and gender. All subjects read a word-list and a paragraph and participated in an informal conversation with the interviewer. In addition, a long-term observation of the community was conducted. The phonological variables were correlated with extralinguistic factors using VARBRUL. LPRS shows almost nonexistent (e) and (o) raising, preserving the pattern found in IPRS. Lorain MAS and LPRS are converging in their use of (j), but the merger varies within each age and generation. The two groups are diverging in their use of (r), presenting different degrees of divergence depending on generation and age group. The Spanish spoken by second and third generation LPRS speakers shows influence from AE in the use of a labiodental [v] for (b) and a retroflex for (r). Indirectly, AE influences first generation speakers not proficient in AE through contact with those speakers of the first generation with more exposure to AE. In general, the results reveal that LPRS exhibits continuity from IPRS preserving many of the features transmitted from IPRS though it also diverges from the latter to some extent. Although predictions are speculativ (open full item for complete abstract)

    Committee: Donald Winford Brian Joseph (Advisor) Subjects: Language, Linguistics
  • 5. Ndoci, Rexhina The Linguistic Construction of Albanianness in Greece: Memes, Names, and Name-calling

    Doctor of Philosophy, The Ohio State University, 2024, Linguistics

    As a result of migration starting in 1990 Albanians constitute the largest ethnic minority and a considerable part of the population of Greece today. This work examines how Albanianness is constructed in Greece through various avenues. First, a linguistic and thematic analysis of internet memes that target the Greek of Albanians shows that the stigmatization of Albanians is still present in the Greek society as it was when they first arrived albeit is less direct. The analysis also shows the enregisterment of a Mock Albanian Greek or a Pan-foreign L2 Greek that is evident and is disseminated through the internet memes. Second, an analysis of semi-structured interviews with Albanian migrants in Greece shows the strategies Albanians have developed in order to navigate this hostile environment in which they live. One of them is to reject ethnic labels such as Αλβανος [alvanos] ‘Albanian.MASC' and Αλβανεζα [alvaneza] ‘Albanian.FEM' that have come to be ethnoracial slurs in Greek along with being used as labels of ethnicity. These are replaced by high register forms that do not carry the slur potential such as Αλβανη [alvani] ‘Albanian.FEM' or have been reclaimed and imbued with positive meanings that express ethnic solidarity. Others reject ethnic labels altogether and show preference for periphrastic constructions centering nationality such as απο την Αλβανια ‘from Albania'. Periphrasis allows them to make a cautious claim to Albanianness but not the negative indexicality of Albanianness, as well as to cautiously suggest a claim to Greekness. While Greekness is not something the second-generation can openly claim despite most of them holding Greek citizenships and spending their formative years in Greece, they feel that Greekness describes part of their identities. Another strategy by which Albanians navigate xenophobia is family and personal name changes and Hellenizations which deracialize them, removing the indexical link to their Albanianness, and reracialize them (open full item for complete abstract)

    Committee: Brian Joseph (Advisor); Anna Babel (Committee Member); Kathryn Campbell-Kibler (Committee Member) Subjects: Linguistics
  • 6. Rohrer, Thomas Applying the Inhibitory Cascade Model to Molar Series of Two Human Population Samples

    Master of Arts, The Ohio State University, 2022, Anthropology

    The Inhibitory Cascade Model (ICM) is a model of molar development positing that molar tooth germs influence one another's growth by a balance of activator and inhibitor molecules as they form in series. Previous research on mammals has generally validated the model, but conformation of human molars to ICM predictions has been questioned. Previous work on humans has also not assessed the extent to which population variation in molar proportions conforms to ICM predictions. Here, two different human population samples are assessed based on expectations of the ICM. Both are expected to exhibit a pattern of decreasing size across molar series, as has been shown to be the most frequent pattern in previous studies for humans. However, the two populations are predicted to differ in terms of molar size ratios given that one population sample (Seminole Nation) derives from an ancestry group that exhibits high frequencies of third molar agenesis, while the other (Gullah-Geechee) does not. If the ICM influences differences in third molar agenesis between peoples of Native American vs. African ancestry, then it is expected that molar sizes will decrease across the molar row to a greater extent in the Seminole than they do in the Gullah. Such a difference, though not definitively demonstrating a role for the ICM in third molar agenesis, would be consistent with the possibility that in the Seminole, there is greater inhibition of growth across the molar row than there is in the Gullah. Buccolingual (BL), mesiodistal (MD), and area (BL x MD) dimensions of the teeth were analyzed. Frequencies of size proportion relationships for molar areas were analyzed, with attention to patterns consistent with ICM expectations. Molar size ratios for the BL and MD dimensions as well as for areas were compared for the two population samples in simple and multiple linear regression models. Across the entire sample set, there is a clear pattern aligned with expectations of the ICM, with greatest (open full item for complete abstract)

    Committee: Debbie Guatelli-Steinberg Dr. (Advisor); John Hunter Dr. (Committee Member); Hubbe Mark Dr. (Committee Member); Barbara Piperata Dr. (Committee Member) Subjects: Physical Anthropology
  • 7. Weakley, Jacob Late Holocene Chronoclinal Variation in White-tailed Deer (Odocoileus Virginianus) Associated with Human Behavior in the Ohio River Valley

    MA, University of Cincinnati, 2021, Arts and Sciences: Anthropology

    This study investigates the influence of climate change and human behavior in the Ohio River Valley, USA, on white-tailed deer (Odocoileus virginianus) body mass during the middle to late Holocene. White-tailed deer astragali were selected from four sites with various ages spanning different climates and human activity levels: the Late Archaic Dupont Village (33Ha11) (4834 to 4515 calibrated years before present; Cal BP), Middle Woodland Twin Mounds Village (33Ha24) (1179 to 972 Cal BP), Middle Fort Ancient Stateline Village (33Ha58) (724 to 553 Cal BP), and Late Fort Ancient Wynema Village (33Ha837) (500 to 422 Cal BP). When climate was cold (Middle Woodland and Late Fort Ancient periods), deer body mass should be large; when climate was warm (Late Archaic and Late Fort Ancient periods), body mass should be small. Additionally, deer body mass would be expected to increase as human activity promoting agriculture increased (starting at the Middle Woodland period), as this leads to an increase in the available food supply of white-tailed deer. Astragalus medial depth, length, and distal width were measured and used to estimate overall deer body mass. Male white-tailed deer were largest during the Late Fort Ancient cultural period and smallest during the Middle Woodland cultural period. Female deer did not show significant body mass differences over time, suggesting impacts on male body mass were not as influential on female deer. These trends are inconsistent with those expected if climate were the only factor influencing body mass. Instead, changes in white-tailed deer body mass are most likely the result of a combination of climate and human behavior. In particular, the data suggest human behavior via the initiation of agriculture and earthwork construction (as seen during the Middle Woodland period) had a negative impact on deer body mass due to the rapid human-led environmental change.

    Committee: Kenneth Tankersley Ph.D. (Committee Chair); Brooke Crowley Ph.D. (Committee Member) Subjects: Archaeology
  • 8. Reed, Andrew Biogeography of West Nile Virus in Ohio

    Master of Science (MS), Bowling Green State University, 2021, Biological Sciences

    The West Nile virus (WNV), part of the flavivirus group, is one of the most recognized arboviruses in the world. Following its 1937 discovery in Uganda, it subsequently expanded into the Middle East, then to Europe, and ultimately established a presence in North American in 1999. The virus is maintained in the environment as an enzootic cycle primarily between Culex species of mosquitoes and various avian hosts. WNV has gained much attention for both its effect on avian hosts and for its ability to cause serious infections in dead-end hosts such as humans. With the WNV circulating within the United States now for 20 years, significant mutational changes have occurred resulting in the selection of a new, more virulent WNV genotype. There are limited studies on potential factors involved in the selection of new WNV phenotypes. Further study of potential factors, geographical correlation, and variants found in WNV genome warrants investigation. WNV samples collected in Ohio to screen for incidence provide a resource for investigation of potential genetic variation of WNV relative to specific biomes. This study has piloted a strategy wherein cDNA from WNV positive RNA extracts and subsequent amplification by the polymerase chain reaction (PCR) affords WNV genetic material for evaluation. Because major changes in WNV pathogenicity have corresponded to changes in the envelope gene product, my study has targeted that region of the WNV genome. These efforts resulted in the amplification and sequence determination of a region of the envelope gene that showed variation relative to WNV isolates from other regions of North America.

    Committee: Raymond Larsen Dr. (Advisor); Julia Halo Dr. (Committee Member); Daniel Pavuk Dr. (Committee Member) Subjects: Biology; Ecology; Molecular Biology
  • 9. Willie, Nigani Plasmodium falciparum Histidine-rich Protein 2 Gene Variation and Malaria Detection in Madagascar and Papua New Guinea

    Master of Sciences, Case Western Reserve University, 2018, Biology

    Plasmodium falciparum histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, parasites lacking the pfhrp2 gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. In this study, the performance of the SD Bioline Malaria Ag P.f/Pan RDT together with pfhrp2 variation in Madagascar was evaluated. The study also evaluated pfhrp2 gene variation in PNG. Genomic DNA isolated from patient blood samples from Madagascar (n = 260) and PNG (n = 169) were subjected to molecular detection (18S rRNA PCR, followed by post-PCR LDR-FMA) for the identification of Plasmodium spp. infections. PCR amplification of the pfhrp2 gene, sequencing and gene analysis enabled studying of gene variation. PCR diagnosis showed that 28.8% (75/260) in Madagascar and 81.1% (137/169) in PNG had Plasmodium infections. 94.6% (71/75) and 91.2% (125/137), of the infections were P. falciparum in Madagascar and PNG, respectively. Compared to molecular detection, the sensitivity and specificity of the RDT (in Madagascar) for P. falciparum detection were 87% and 89%, respectively. From randomly selected pfhrp2 gene-positive samples, 16 pfhrp2 gene sequences from Madagascar and 18 pfhrp2 gene sequences from PNG were generated. Although extensive variations of the pfhrp2 gene were observed in both countries, this study showed that there was no indication of pfhrp2 deletion. The study also did not observe a clear correlation between pfhrp2 sequence structure and RDT detection rates. Although the absence of pfhrp2 deletion from the samples screened here is encouraging, continued monitoring of the efficacy of RDTs currently used in Madagascar and PNG is warranted.

    Committee: Peter Zimmerman A. (Advisor); Daniel Tisch J. (Committee Member); Emmitt Jolly R. (Committee Member); Hillel Chiel (Committee Chair) Subjects: Biology; Epidemiology; Genetics; Molecular Biology; Parasitology
  • 10. Tadepally, Harika Spatiotemporal Variation of Continuous PM2.5 In Cincinnati: Analyzing The Impacts of Local-Scale Emissions Versus Meteorological Variability

    MS, University of Cincinnati, 2017, Engineering and Applied Science: Environmental Engineering

    This study focusses on analyzing the spatiotemporal trends of continuous PM2.5 in the Greater Cincinnati region. The study area consists of seven monitoring stations maintained and operated by the Southwest Ohio Air Quality Agency. PM2.5 data from August of 2011 to June of 2016 was analyzed to delineate the trends in the 24-hour, four-hour averaged and hourly data sets; along with understanding the meteorological variability at the selected sites. Statistical analyses were performed using Pearson's correlations, Analysis of Variance (ANOVA), Tukey's Honest Significant Differences (HSD), K-means clustering, silhouette analysis. Pearson's correlations were calculated for hourly, four-hour and 24-hour temporal scaled, while, ANOVA and Tukey's HSD tests were conducted on the 24-hour, weekday-weekend, and on the hourly data grouped into six activities, to check for site-by-site variability. The 24-hour aggregated meteorological data was clustered and PM2.5 within each cluster was analyzed. The yearly trends suggest significant decrease (~20%) of pollutant concentrations from 2011 to 2016 across all the sites. The seasonal trends indicate that during summers in Cincinnati, higher concentrations are observed at all sites except Colerain, where winters are the highest. The Pearson's correlations suggested ~20% variability among all the sites, while the diurnal patterns indicated higher correlations during the day. The trends observed in the correlations of four-hour integrated dataset are similar to what was detected in the hourly data, thereby underscoring the hourly data's validity. The results of ANOVA suggested a statistically significant variation among all the sites (p < 2e-16), while the Tukey's HSD indicated that 16 out of 21 site-pairs were spatially variable at the 24-hour level. The spatial variability reduced to 12 out 21 site-pairs on weekends when compared to 14 site-pairs on weekdays, suggesting that local transportation patterns play an important role i (open full item for complete abstract)

    Committee: Sivaraman Balachandran Ph.D. (Committee Chair); Jonathan Corey Ph.D. (Committee Member); Mingming Lu Ph.D. (Committee Member) Subjects: Environmental Engineering
  • 11. Cowen, Benjamin Bregman Operator Splitting with Variable Stepsize for Total Generalized Variation Based Multi-Channel MRI Reconstruction

    Master of Sciences, Case Western Reserve University, 2015, Applied Mathematics

    This paper presents a fast algorithm for total generalized variation (TGV) based image reconstruction of magnetic resonance images collected by a technique known as partial parallel imaging (PPI). TGV is a generalization of the commonly employed total variation (TV) regularizer. TV reconstructs piecewise constant images and is known to produce oil-painting artifacts, while TGV reconstructs images with piecewise polynomial intensities and largely avoids this issue. The proposed algorithm combines the Bregman Operator Splitting with Variable Stepsize (BOSVS) approach derived by Chen, Hager, et al. [8] with the closed-form expressions for the TGV subproblem that arises in the alternating directional method of multipliers, derived by Guo, Qin and Yin [13]. The ill-conditioned inversion matrix that comes from PPI is approximated according to a stepsize rule similar to that in BOSVS. The stepsize rule starts with a Barzilai-Borwein step, then uses a line search to ensure convergence and eciency. The proposed regularizer is shown to achieve better results than TV, especially for reconstructing smooth details, in sampling conditions as low as 7.87%.

    Committee: Weihong Guo PhD (Advisor); Steven Izen PhD (Committee Member); Julia Dobrosotskaya PhD (Committee Member) Subjects: Applied Mathematics
  • 12. Russ, Robert Examining Regional Variation Through Online Geotagged Corpora

    Master of Arts, The Ohio State University, 2013, Linguistics

    Large-scale dialect surveys have long been a fundamental component of sociolinguistics and variation studies, but they have traditionally required significant investments of time and resources to collect relatively small amounts of data. In this study, I examine whether textual corpora collected from the Internet, particularly the social-networking website Twitter, can be used to conduct such surveys more quickly with less effort. I discuss the utility of Twitter as a linguistic data source, explain the computational and linguistic methods necessary to collect and process worthwhile data, and use corpora from Twitter to plot the distribution of three regional variables in American English: soft drink terminology, the use of `hella' as an intensifier, and the morphosyntactic construction `needs X-ed'. I find that these corpora can replicate the findings of previous surveys (as seen with soft drink terms), reveal the existence of previously undocumented regional divides (as seen with `hella'), and highlight possible examples of ongoing linguistic diffusion (as seen with `needs X-ed'). I conclude that, although this method has issues with tracking certain types of sociolinguistic variables, it is still a promising source of data for conducting rapid studies in many areas of regional linguistic variation.

    Committee: Kathryn Campbell-Kibler (Advisor); Brian Joseph (Committee Member) Subjects: Computer Science; Linguistics; Sociolinguistics
  • 13. BASU, SHUBHANKAR Performance Modeling and Optimization Techniques in the Presence of Random Process Variations to Improve Parametric Yield of VLSI Circuits

    PhD, University of Cincinnati, 2008, Engineering : Computer Engineering

    As semiconductor industry continues to follow Moore's Law of doubled devicecount every 18 months, it is challenged by the rising uncertainties in the manufacturing process for nanometer technologies. Manufacturing defects lead to a random variation in physical parameters like the dopant density, critical dimensions and oxide thickness. These physical defects manifest themselves as variations in device process parameters like threshold voltage and effective channel length of transistors. The randomness in process parameters affect the performance of VLSI circuits which leads to a loss in parametric yield. Conventional design methodologies, with corner case based analysis techniques fail to predict the performance of circuits reliably in the presence of random process variations. Moreover, the analysis techniques for detection of defects in the later stages of the design cycle result in significant overhead in cost due to re-spins. In recent times, VLSI computer aided design methodologies have shifted to statistical analysis techniques for performance measurements with specific yield targets. However, the adoption of statistical techniques in commercial design flows has been limited by the complexity of their usage and the need for generating specially characterized models. This also makes them unsuitable in repeated loops during the synthesis process. In this dissertation, we present an alternate approach to model and optimize the performance of digital and analog circuits in the presence of random process variations. Our work is targeted for a bottom-up methodology providing incremental tolerance to the circuits under the impact of random process variations. The methodologies presented, can be used to generate fast evaluating accurate macromodels to compute the bounds of performance due to the underlying variations in device parameters. The primary goal of our methodology is to capture the statistical aspects of variation in the lower levels of abstraction, while (open full item for complete abstract)

    Committee: Ranga Vemuri PhD (Committee Chair); Harold Carter PhD (Committee Member); Wen-Ben Jone PhD (Committee Member); Carla Purdy PhD (Committee Member); Srinivas Katkoori PhD (Committee Member) Subjects: Computer Science
  • 14. Cigeroglu, Ender Development of microslip friction models and forced response prediction methods for frictionally constrained turbine blades

    Doctor of Philosophy, The Ohio State University, 2007, Mechanical Engineering

    High cycle fatigue failure of turbine and compressor blades due to resonance in the operating frequency range is one of the main problems in the design of gas turbine engines. In order to suppress excessive vibration of blades, dry friction dampers are used by engine manufacturers. Because of its mathematical simplicity, macroslip models are widely used and they perform well if the contact pressure acting on the friction interface is low. However, in case of high contact pressure and/or large contact areas, partial slip in the friction interface occurs. In order to obtain accurate forced response predictions for frictionally constrained bladed disks, microslip modeling is necessary. However, due its mathematical complexity, microslip friction models in literature are developed for simple cases, which leave the realistic bladed disk models unaddressed. In this research, it is aimed to develop microslip friction models and forced response prediction methods, which can be used in realistic bladed disk models, and can handle complex contact kinematics resulting in friction damper applications. This leads to the development of the following microslip friction models: one-dimensional dynamic microslip friction model, microslip friction model for one-dimensional motion with normal load variation induced by normal motion, microslip friction model for two-dimensional periodic motion with normal load variation, three-dimensional microslip friction model with normal load variation. A wedge damper model and forced prediction method for frictionally constrained blades is developed. The model developed considers the damper as a solid body with rigid body modes and elastic modes, where dampers and blades are modeled by finite elements. Damper moves freely in between adjacent blades; therefore, damper motion is not constrained artificially. The microslip friction models developed are associated with contact stiffness through out the contact interface. Unlike other model parameters, (open full item for complete abstract)

    Committee: Chia-Hsiang Menq (Advisor) Subjects: Engineering, Mechanical
  • 15. Temple, Daniel Human biological variation during the agricultural transition in prehistoric Japan

    Doctor of Philosophy, The Ohio State University, 2007, Anthropology

    This dissertation reconstructs behavioral and biological variation among prehistoric Jomon foragers and Yayoi agriculturalists using bioarchaeological data. The Jomon were a group of foragers from Japan dating to approximately 13,000 until 2500 BP. The Yayoi were the first agriculturally dependent people on the Japanese islands, dating from 2500 until 1700 BP. Data collected from human skeletal remains were used to test the following hypotheses about these groups: 1) Patterns of systemic stress among prehistoric Jomon foragers was variable; 2) Systemic stress increased following the transition to agriculture; 3) Systemic stress patterns among Yayoi agriculturalists was variable; 4) Differences in body size and proportions will be observed among and between Jomon foragers and Yayoi agriculturalists; 5) Systemic stress experienced during the agricultural transition in prehistoric Japan was greater than other East Asian agriculturalists and improved compared with North American agriculturalists. Non-specific indicators of stress suggest the Jomon from western Japan experienced greater disease loads than those from eastern Japan. This trend is associated with plant dependent diets and resource scarcity in western Japan. Stature variation is, however, not recorded between these two groups indicating that systemic stress severity was not different between the eastern and western Jomon. Oral health declined following the transition to agriculture in prehistoric Japan in association with increased consumption of carbohydrates. Non-specific indicators of stress reduced in frequency following the transition to agriculture. These trends indicate that the quality of life for prehistoric Japanese was generally improved compared to prehistoric North American agriculturalists and similar to that observed in prehistoric East Asian agriculturalists. In addition, patterns of health observed among Yayoi agriculturalists, specifically enamel hypoplasia and stature variation, indicates (open full item for complete abstract)

    Committee: Clark Larsen (Advisor) Subjects: Anthropology, Physical
  • 16. Yavaş, Gökhan Algorithms for Characterizing Structural Variation in Human Genome

    Doctor of Philosophy, Case Western Reserve University, 2010, EECS - Computer and Information Sciences

    Until fairly recently, single nucleotide polymorphisms (SNPs) were thought to be the main source of variation in the human genome. With the advent of high-throughput genome scanning technologies, it has been revealed that there are other forms of genomic variation beyond single base-pair substitutions. These structural alterations include insertions, deletions, inversions, translocations, tandem repeats of DNA sequences and copy number variants (CNVs). Concisely, all of these alterations are referred as structural variations. CNVs represent the segments of the genome that are polymorphic with regard to genomic copy number. Copy number polymorphisms (CNPs), which can be considered as a specific category CNVs, are defined to be copy number variants that are present, with identical boundaries (and are therefore likely identical-by-descent), in at least 1% of the human population. Tandem repeats, on the other hand, are described as serially repeated segments of the human genome which may have repeat units several hundred kilobases in size. CNVs, which have been shown to have a role in various diseases such as Alzheimer disease, Crohn's disease, autism and schizophrenia, can be caused by various structural mutations such as duplications and deletions. In the effort to scan the entire genome of human populations, as well as individuals, for CNVs (also CNPs) and tandem repeats, SNP arrays and paired end sequence mapping data have emerged as important tools. In this thesis, we study the problem of identifying CNVs, CNPs and tandem repeats from these data sources. We first frame CNV identification as an optimization problem with an objective function that is explicitly designed so that its optimal solution is the most accurate set of CNV calls. Our method, termed COKGEN, finds the best solution using a variant of the well-known heuristic simulated annealing. Next, we present a method for identifying and genotyping common CNPs. The proposed method, POLYGON, draws strength fr (open full item for complete abstract)

    Committee: Mehmet Koyuturk (Committee Chair); Thomas LaFramboise (Committee Member); Meral Ozsoyoglu (Committee Member); Jing Li (Committee Member) Subjects: Bioinformatics; Computer Science
  • 17. Donelson, Nathan Inter- and Intraspecific Variation in the Superfamily Pneumoroidea

    Doctor of Philosophy (Ph.D.), Bowling Green State University, 2007, Biological Sciences

    This dissertation concerns phenotypic plasticity of male morphology within South African bladder grasshoppers (Orthoptera: Pneumoroidea) from an individual to the species level. Wings and a large inflated abdomen used for acoustic courtship and communication are characteristic of adult male pneumoroids. However, a secondary (‘alternate') male morph has been identified in three species, which completely lacks the appearance and associated dispersal and signaling behaviors. These characteristics are shared with three monotypic genera formerly raised to accommodate taxa with atypical males. As the aforementioned characteristics are critical for mate localization, the absence of such structures and behaviors demands explanation. The first chapter examines three pneumoroid species that possess both male morphs to determine how similar the uninflated morph is across taxa. The morphology of each species and morph was compared using Multivariate Analysis of Variance (MANOVA) and linear regression. Results show that the morphological differences between inflated and uninflated males is similar across species. This demonstrates that the uninflated phenotype is largely conserved within the Bullacris genus. The second chapter takes a broader comparative approach. It expands the morphometric analysis to investigate three strictly uninflated species and asks whether they are in fact uninflated morphs of inflated species with which they are sympatric. Based on results from chapter 1, we propose that the known differences between morphs can be used to create ‘hypothetical' uninflated males for any inflated taxa. MANOVA and Discriminant Function Analysis (DFA) then compare the hypothetical males to the actual uninflated taxa. Our results suggest that each of the uninflated male taxa can be placed into inflated taxa. This now places dual morphologies in at least three genera and perhaps the entire superfamily. The third chapter uses geographic and morphological data of two widespread (open full item for complete abstract)

    Committee: Moira van Staaden (Advisor) Subjects:
  • 18. Hayes, Matthew Algorithms to Resolve Large Scale and Complex Structural Variants in the Human Genome

    Doctor of Philosophy, Case Western Reserve University, 2013, EECS - Computer and Information Sciences

    It has been shown that large scale genomic structural variants (SV) are closely associated with disease onset. In particular, the presence of these abnormalities may contribute to the onset and susceptibility of cancer through various mechanisms. Knowing the location and type of these variants can assist medical researchers in making insights into methods for diagnosis and treatment. It is also important to develop efficient methods to locate these variants. This thesis presents several algorithms for identifying and characterizing structural variants using array comparative genomic hybridization (aCGH) and high throughput next-generation sequencing (NGS) platforms. The aCGH-based algorithm (CGH-Triangulator) is considerably faster than a state-of-the-art method for identifying change points in aCGH data, and it has greater prediction power on datasets with low-to-moderate levels of noise. The NGS-based algorithms include methods to identify basic SV types, including deletions, inversions, translocations, and tandem repeats. They also include methods to identify double minute chromosomes, which are more complex structural variants. These methods use a hybrid strategy to identify variants at base-pair resolution. Using two primary prostate cancer datasets and simulated datasets, we compared our methods to previously published NGS algorithms. Overall, our methods had favorable performance with respect to breakpoint prediction accuracy, sensitivity, and specificity. In particular, this thesis presents one of the first attempts to algorithmically detect double minute chromosomes, which are complex rearrangements that are present in many cancers.

    Committee: Jing Li (Advisor) Subjects: Bioinformatics; Computer Science; Molecular Biology
  • 19. Arur, Manohar Analysis of latitude observations for detection of crustal movements /

    Master of Science, The Ohio State University, 1970, Graduate School

    Committee: Not Provided (Other) Subjects:
  • 20. Kline, Joshua On Local and Nonlocal Least Gradient Problems in Metric Measure Spaces

    PhD, University of Cincinnati, 2024, Arts and Sciences: Mathematical Sciences

    In this dissertation, we study variational problems related to functions of bounded variation, sets of finite perimeter, and their nonlocal analogs in the metric measure space setting. We begin by considering the least gradient problem, min\{||Du||(Ω): u∊BV(Ω), u=f on ∂Ω}, where Ω⊂X is a bounded domain, f∊L^1(∂Ω) is a prescribed boundary function, and ||Du||(Ω) is the BV-energy of u in Ω. For domains satisfying certain geometric assumptions, we study the sub-class of L^1-boundary data for which solutions to the least gradient problem exist. While solutions are known to exist for continuous boundary data, it is also known that not all L^1-boundary data admit solutions, even in the Euclidean setting. We provide examples in the Euclidean setting which illustrate that the class of solvable L^1-boundary data is nonlocal in a certain sense and does not in general form a vector space. We then prove existence of solutions for various discontinuous boundary data in the metric measure space setting. In the second portion of this dissertation, we introduce and study the following modification of the least gradient problem in the metric measure space setting: min{||Du||(Ω):ψ_1≤ u ≤ψ_2 in Ω, f≤u≤g on ∂Ω}. Here, ψ_1 and ψ_2 are obstacle functions in the domain, and f and g are prescribed L^1-boundary data. We construct solutions to this problem when the obstacle functions and boundary data are continuous. As candidate functions need not be fixed on the boundary, standard compactness arguments fail to yield weak solutions of the form related to the standard least gradient problem. To overcome this issue, we introduce a notion of ε-weak solutions, which minimize BV-energy in slight enlargements of the domain. In the last portion of this dissertation, we adapt a nonlocal variational problem, originally studied by Caffarelli, Roquejoffre, and Savin in ℝ^n, to the metric measure space setting. This minimization problem involves sets of finite fractional perimete (open full item for complete abstract)

    Committee: Nageswari Shanmugalingam Ph.D. (Committee Chair); Panu Kalevi Lahti Ph.D M.A B.A. (Committee Member); Stephan Pelikan Ph.D. (Committee Member); Gareth Speight Ph.D. (Committee Member) Subjects: Mathematics