Master of Science, The Ohio State University, 2023, Civil Engineering

Slip formed concrete has been used extensively for pavements, barriers, and bridge railings due to its ease and speed of construction compared to cast in place concrete. It involves continuously pouring concrete into a formwork that moves slowly upward and as the concrete is poured, it hardens, creating a seamless, continuous structure. However, despite decades of use, slip formed concrete deterioration persists and often exceeds that of other construction methods. The Ohio Department of Transportation has identified the problems of horizontal cracking at longitudinal rebar level in the slip-formed parapet of the bridges across all the districts of Ohio state. The horizontal crack at the rebar level can be contributed by the different factors such as mix design, poor quality of materials used in construction, inadequate curing of the concrete, or improper design and construction techniques, weak bond strength of rebar and concrete, temperature variation and moisture content. The objective of this study was to detect the internal flaws, particularly, the horizontal crack around the top longitudinal reinforcement of the slip form concrete barrier with the use of the nondestructive testing method: Ultrasonic Pulse Velocity (UPV) and MIRA, and to provide the recommendation of the use of the nondestructive testing method to ODOT, so that the timely correction steps can be taken to detect and fix the deterioration and extend the service life of the slip formed concrete railing. Initially iv the concrete blocks with and without the defect characteristics, such as varying sizes and locations were cast in the lab and the UPV wave velocity was studied at the different locations of both samples. Based on these results, UPV wave velocity results obtained from the field testing were compared and interpreted to detect the presence voids around the top rebar.

Committee: Lisa Burris (Advisor); Anthony Massari (Committee Member); Abdollah Shafieezadeh (Committee Member) Subjects: Civil Engineering

Master of Science (MS), Bowling Green State University, 2018, Physics

Photographic plates in the Harvard collection show the star V1835 Aql brightening by a factor of 100 in flux over four years starting in 1899, remaining at maximum for four years, then declining below the depth of the plates \cite{williams2005}. This nova-like behavior is very atypical for most variable stars and as a result there has been much debate over the exact nature of V1835 Aql. This debate was ended by the discovery of a Raman scattered emission line at 6824 \AA, which is unique to symbiotic binaries and unequivocally identifies V1835 Aql as a symbiotic star \cite{bk12}. Our research hopes to expand upon our knowledge of V1835 Aql through analysis of five years worth of multi-band optical time-series photometry. From this we have found the period of this star to be 419 days. This long period confirms that V1835 Aql is a symbiotic star and not its closer orbiting cousin, a cataclysmic variable. We have also determined the properties of all the other variable star candidates near V1835 Aql, of which there are 31.

Committee: Andrew Layden (Advisor); John Laird (Committee Member); Dale Smith (Committee Member) Subjects: Astronomy; Astrophysics; Physics

Master of Science (MS), Bowling Green State University, 2017, Physics

We present the results of a 6-year observing campaign conducted using the PROMPT-5 telescope to detect, identify and characterize long-period variable (LPV) stars in the metal-rich globular cluster NGC 6388. LPV stars are asymptotic giant branch stars that exist on a Mira-to-semi-regular-to-irregular continuum in terms of the regularity of their variable behavior. The long time-baseline was found to be fruitful in characterizing that aspect of LPV pulsation that cannot be captured in shorter campaigns. The ISIS image subtraction package is used for variability detection and the production of flux difference photometric data. We have also manually recovered known variable stars with use of their published celestial coordinates. Newly detected sources of variability were ranked on the basis of a variability index. An attempt was also made to quantitatively characterize the positions of LPV stars on the regularity spectrum with a newly defined regularity index, with partial success in the case of known variables. The known and new variables are discussed and characterized and their cluster membership determined with the use of a color-magnitude diagram and the variable's projected distance from the cluster center. Out of 72 variables studied, two of which were found to be duplicated in the literature, 56 are known variables that were detected or recovered. The LPVs detected number to 26 and 16 known and new, respectively. Almost all LPVs' periods are determined using the period-dispersion minimization method. A list of suspected variables, which require higher-resolution observations to confirm, amounts to an additional 22 stars. A period-luminosity relation is determined using the available literature data and our own data.

Committee: Andrew Layden Dr. (Advisor); John Laird Dr. (Committee Member); Dale Smith Dr. (Committee Member) Subjects: Astronomy; Astrophysics; Physics

Master of Arts (MA), Bowling Green State University, 2014, Popular Culture

In this thesis, I explore the ways in which several characters in the anime Fullmetal Alchemist: Brotherhood play with gender, and what impact that gender play has on larger social structures within the narrative. I use a close reading of the text, and of four characters in particular (Lust the Lascivious, Envy the Jealous, and the Armstrong siblings), to deduce how hegemonic patriarchal powers influence and control gender performance for those characters closely related to them, and spur on gender play in characters defying said powers. These characters occupy a liminal space between generations that is vital to their gender play. I argue that views on gender in this particular series are a symptom of shifts in generational understandings of the world overall, not just in relation to gender performance.

Committee: Kristen Rudisill (Committee Chair); Satomi Saito (Committee Member); Becca Cragin (Committee Member) Subjects: Gender; Gender Studies; Mass Media

Doctor of Philosophy, The Ohio State University, 2010, Spanish and Portuguese

Based on a 2007 Fulbright funded documentary film project; this dissertation concerns the highland Afro-Ecuadorian communities of the Chota-Mira valley. The afrochotenos are the direct descendents of enslaved Africans brought to the region by Jesuits to labor the local sugar-cane plantations during the seventeenth century. Their particular history, cultural traditions, beliefs, customs, and ways of life distinguish them from Ecuador's indigenous, mestizo, and coastal black population. Despite their contribution to the nation's development and identity as a pluri-cultural state, the afrochotenos face extreme social, political, and economic marginalization as a result of their displacement and origins with the trans-Atlantic slave trade, subjugation and oppression as slaves, uneven integration, and continued exploitation and discrimination post emancipation. As such, the afrochotenos are made invisible in representations of the nation's history and culture, save only for their presence on the national soccer team. While academic interest in topics concerning Afro-Hispanic and Afro-Andean communities is growing, much work remains in not only documenting, but critically exploring these subaltern histories and traditions in terms of the stories of oppression, struggle, resistance, and hope they tell. I thus examine the afrochoteno song and dance genre known as La Bomba in relation to the socio-historical development and struggles of the afrochoteno communities as a means of illuminating afrochoteno culture and their condition as subalterns. Though marginalized for much of the twentieth century, La Bomba is today recognized nationally as a symbol of afrochoteno identity thanks in part to a revival spurred by the cultural preservation efforts of the Afro-Ecuadorian socio-political project and movement known as etnoeducacion. This initiative seeks to validate and strengthen afrochoteno identity in reclaiming local traditions and educating afrochoteno youth about Afro-Ecuad (open full item for complete abstract)

Committee: Ileana Rodriguez (Advisor); Lúcia Costigan (Committee Member); Samuel Amell (Committee Member) Subjects: Latin American History; Latin American Literature; Music

Master of Science (MS), Bowling Green State University, 2011, Physics

Studying the late stages of stars is essential to understand the process of stellar evolution. Depending on their masses and properties, some stars become unstable at the end of their evolutionary state and hence they start pulsating. Their brightness and surface temperature change with their pulsations and hence we see them as variable stars. We are looking for long period variable stars (LPVs) in the globular cluster NGC 6496. We observed the cluster from February 2009 till October 2010 using a 0.41m telescope in the V and I bandpasses. We have identified 11 variable stars in the cluster. 6 of them are new discovered LPVs in which 3 of them are semiregular LPVs and the rest 3 are irregular LPVs. We plotted the color magnitude diagram (CMD) of this cluster and all our LPVs were detected on the RGB/AGB. 5 of the 11 variable stars are short period variable stars in which 4 of them are W UMa binary stars and 1 is an Algol binary star. The light curves of all these stars are plotted in this paper and the periods were detected using different period-finding methods.

Committee: Layden Andrew PhD (Committee Chair); John Laird PhD (Committee Member); Dale Smith PhD (Committee Member) Subjects: Astronomy; Astrophysics; Physics

Master of Science (MS), Bowling Green State University, 2011, Physics

We have searched for Long Period Variable (LPV) stars in the metal-rich cluster NGC 6388 using time series photometry in the V and I bandpasses. A CMD was created, which displays the tilted red HB at V = 17.5 mag. and the unusual prominent blue HB at V = 17 to 18 mag. Time-series photometry and periods have been presented for 63 variable stars, of which 30 are newly discovered variables. Of the known variables nine are LPVs. We are the first to present light curves for these stars and to classify their variability types. We find 3 LPVs as Mira, 6 as Semi-regulars (SR) and 1 as Irregular (Irr.), 18 are RR Lyrae, of which we present complementary time series and period for 14 of these stars, and 7 are Population II Cepheids, of which we present complementary time series and period for 4 of them. The newly discovered variables are all suspected LPV stars and we classified them, using time series photometry and periods, as Mira for 1 star, SR for 15 stars, Irr for 7 stars, Suspected Variables for 7 stars, out of which there are 3 very bright stars that could have overexposed the CCD, with no definite borderline between the SR and Irr stars. Once classified we used probable distance for the cluster center and location on the CMD to establish possible membership, which left us with 63 possible cluster members, but the crowdedness of the cluster and the fact that the cluster is located near the bulge of the Milky Way prevents us from establishing a better certainty for its membership.

Committee: Andrew C. Layden Dr. (Advisor); John Laird Dr. (Committee Member); Dale W. Smith Dr. (Committee Member) Subjects: Astronomy; Astrophysics; Physics

Master of Science (MS), Bowling Green State University, 2010, Physics

Photometry for the metal-rich globular cluster NGC 6553 has been done and is presented in both V and I banpasses. A color magnitude diagram for this cluster was created which indicates the presence of two distinct giant branches that separate the cluster population from the field population at I = 12.2 mag. Time-series photometry is presented for 49 stars, 22 of which are considered cluster members. Cluster membership was found by locating them on the cluster giant branch. Ten of these 22 cluster members are new discoveries while the other twelve were found during a study done by Lloyed Evans and Menzies in 1972. Where possible, properties, such as average period, average amplitude, and the observed range of magnitudes of the variable star candidates are discussed. Lloyd Evans and Menzies did not investigate the stars' properties, but they provided generalized sub-classifications for them. Their findings included eleven irregular/semi-regular variables and one Mira variable. We, on the other hand, provide specific sub-classifiactions for the individual stars. Comparing our results of the same twelve stars to Lloyd Evans and Menzies', we find that we sub-classified them as ten irregular/semi-regular variables, one Mira variable, and one possible binary star system. We do not find a definite borderline between the irregular and the semi-regular variable star classes. Also, we have made the observation that there is no trend of sub-classes with respect to the position on the giant branch. This leads to the conclusion that there is no smooth transition from the position of irregular/semi-regular variables to the position occupied by Mira-type variables, but rather a sudden jump. This same phenomenon has been observed by Lebzelter and Wood in a paper published in 2005.

Committee: Andrew Layden (Advisor); John Laird (Committee Member); Dale Smith (Committee Member) Subjects: Astronomy; Astrophysics; Physics