Master of Science (MS), Ohio University, 2024, Industrial and Systems Engineering (Engineering and Technology)

In response to escalating inventory costs, dynamic purchasing needs, and the demand for rapid operations in the retail sector, both the warehousing and retail industries have accelerated their pace of innovation. Among these advances, the development of automated warehousing and storage systems stands out. However, despite widespread adoption, a comprehensive framework for effectively implementing these systems remains lacking. Hence, this study proposes a systematic approach that provides a foundational blueprint for harnessing vital information from historical sales data in the deployment of intelligent warehouse systems, incorporating a wide array of Automated Storage and Retrieval Systems (AS/RS) technologies. Specifically, it employs unsupervised machine learning for time series clustering to analyze historical sales data, while adapting and modifying the Recency, Frequency, Monetary (RFM) model to optimize the prioritized management of stock-keeping units (SKUs) in periodic segments.

Committee: Tao Yuan (Advisor); Omar Alhawari (Committee Member); Gary Weckman (Committee Member); Ashley Metcalf (Committee Member) Subjects: Engineering; Industrial Engineering; Management; Sustainability; Systems Design; Technology

Master of Science, Miami University, 2022, Biology

The purpose of this study was to determine whether cold-induced left ventricle hypertrophy in rodents was physiological or pathological in nature. Mice were acclimated to cold (4°C) conditions for 6 weeks to look at the effect of cold exposure and then were kept at room temperature for 10 weeks to look at the recovery from prolonged cold exposure. Hearts from voles collected in summer and winter were also studied. Left ventricular hypertrophy did occur, through eccentric hypertrophy of the heart. Heart function was not impaired after prolonged cold exposure. Mouse hearts were no longer significantly different from controls after the recovery period. Both mice and voles did not show signs of long-term damage from prolonged cold exposure. These results suggest that cold-induced heart enlargement is most like physiological hypertrophy.

Committee: Paul Schaeffer (Advisor); Jennifer Schumacher (Committee Member); Andor Kiss (Committee Member) Subjects: Biology; Physiology

Master of Science, The Ohio State University, 2021, Entomology

Diapause, a period of arrested development that allows mosquitoes to survive inhospitable conditions, is triggered by short daylengths in temperate mosquitoes. Different populations of mosquitoes initiate diapause in response to a specific photoperiod, or daylength, resulting in population-specific differences in annual cycles of abundance. The photoperiod that causes approximately 50% of a population to initiate diapause is known as the critical photoperiod (CPP). In the Northern Hemisphere, northern populations of mosquitoes experience lower temperatures earlier in the year and must be triggered into diapause by longer daylengths than southern populations. CPP is genetically based, but also adapts over time responding to the population's environment. Therefore, CPP has been shown to lengthen 1 hour with an increase of 5 °N latitude or an increase of 122 m altitude, following Bioclimatic Law. While the positive correlation between CPP and latitude/altitude has been established in a few mosquito species, including Aedes albopictus, Ae. triseriatus, Ae. sirennensis and Wyeomyia smithii, we do not know when most other species initiate their seasonal responses. As several of these species transmit important diseases, characterizing the CPP of arthropod vectors could improve existing control by ensuring that surveillance efforts align with the vector's seasonally active period. Additionally, better understanding when mosquitoes and other vectors initiate diapause can reduce the frequency of chemical applications, thereby ameliorating the negative impacts to nontarget insects. Females of Culex pipiens, the primary vector of West Nile virus, enter an adult reproductive diapause. The methods by which Cx. pipiens measures daylength are still unknown. However, clock genes which provide information on the time of day, may also be responsible for the regulation of diapause. Previous studies have shown that the mRNA of several circadian clock genes continue to oscillate throu (open full item for complete abstract)

Committee: Megan Meuti PhD (Advisor); Mary Gardiner PhD (Committee Member); Peter Piermarini PhD (Committee Member) Subjects: Entomology

PHD, Kent State University, 2020, College of Arts and Sciences / Department of Biological Sciences

Freshwater ecosystems are under threat due to ongoing global changes and organic matter decomposition in streams is one at-risk process. The decomposition of organic matter in streams is not only an essential process for downstream food webs, but it also provides direct resources for headwater systems. This dissertation focuses on understanding potential factors influencing the decomposition of leaf litter in both tropical and temperate streams, as well as how these same factors influence invertebrates which feed upon decaying organic matter. First, the importance of seasonal hydrologic patterns on premontane rainforests streams in Costa Rica was studied. Surprisingly, decomposition progressed more rapidly during the dry season than the rainy season, with more macroinvertebrates present during the dry season. Next, in the same premontane rainforest streams experimental rock gabion cages were installed at natural bifurcations to divert small flood disturbances away from one channel, while the other reach remained free flowing. From this, it was determined that small predictable disturbances did alter decay rates, but not detritivore macroinvertebrate communities. In contrast, larger flood disturbances had a consequently greater impact on community dynamics. Finally, we studied the decomposition and invertebrate colonization of non-native invasive Frangula alnus leaves versus native Cornus amomum leaves in Northeast Ohio streams. It was determined that Frangula alnus decomposes more quickly with less invertebrates present, than Cornus amomum which had more macroinvertebrates residing on the leaf litter. This dissertation reveals that the processes control decomposition of leaf litter in streams is complex, and that both environmental, biotic, and abiotic can both influence the rate at which decay progresses.

Committee: Ferenc de Szalay (Advisor); Oscar J. Rocha (Advisor) Subjects: Aquatic Sciences; Biology; Ecology; Entomology; Environmental Studies

Master of Arts, The Ohio State University, 2016, Anthropology

Developmental defects of tooth enamel are generally associated with systemic physiological stress, such as malnutrition and disease, and have recently been linked to seasonal stresses caused by environmental factors such as rainfall and fruit availability. The present study systematically evaluates whether developmental defects of enamel occur with any cyclicity in samples of primates from Southeast Asia, and whether cycles differ between environments, as has been suggested. The chronological sequence of defects was first compared between Bornean and Sumatran orangutans to see whether cycle periodicity differs. A second analysis compared the timing of defect occurrence among seven different primate species all from the same environment and time period (Kinabatangan River, Borneo, 1937). Previous research suggested that environmental factors influence the timing and acquisition of developmental defects and that different environments should be expected to impose different patterns of stress. Here, it was hypothesized that if systemic physiological stresses, such as low caloric intake or disease stress, are strongly influenced by environmental seasonality, then some species might experience these stresses according to a similar schedule. However, given that the causes of developmental enamel defects are multi-factorial, it was alternatively hypothesized that no regular patterning related to environmental cycles would be found across individuals or species either between or within environments. To evaluate whether enamel defects occur cyclically, the entire sequence of enamel growth and not just the intervals between defects had to be considered. This was achieved by creating standard perikymata profiles (SPPs), or standardized teeth, for each sex and species that allowed individual developmental sequences (IDSs) to be generated for each individual, tracking the position of each defect in the context of continuous perikymata (time). The SPPs allowed the number of peri (open full item for complete abstract)

Committee: Debra Guatelli-Steinberg (Advisor); William Scott McGraw (Committee Member); Jeffrey McKee (Committee Member) Subjects: Anatomy and Physiology; Animals; Archaeology; Biology; Evolution and Development; Zoology

Master of Arts, The Ohio State University, 2014, Comparative Studies

The guiding questions of this essay are: What is meant by dwelling? And, how is it that people dwell? In the process of approaching these questions, several key terms are employed. These terms are: dwelling; making; technique; modern technology; and the Gestell of modern technology. Gestell, a term borrowed from the later philosophy of Martin Heidegger, describes an orientation to the physical world unique to the apparatus of modern technology and anathema to dwelling. Dwelling is understood through notions of gathering and relationality: how practices of dwelling weave together a multiplicity of things and experiences. Making, here, refers to that aspect of dwelling which constructs regions and transforms space into made place. Yet, the essay is also attuned to how dwelling takes care, that is, how it makes meaning and thus makes sense. Modern technology represents the process whereby the centrality of technique is made peripheral to production, externalized. It suggests the erosion of meaningful technique in modernity and how this erosion effects the characteristically modern experience of alienation. Four textual sites frame the investigation: First, are selections from the later writings of Heidegger on technology and the plight of dwelling. Second, is an engagement with the writing of anthropologist Tim Ingold. In Ingold, both the dwelling perspective and technique are given a more complex ethnological and environmental elaboration. The other two sites provide the actual sociographic settings in which these terms are enacted and tested: Bronislaw Malinowski's classic, early twentieth-century ethnographic account of Melanesian garden making, Coral Gardens and Their Magic: Soil-tilling and Agricultural Rites in the Trobriand Islands; with particular attention to the process of new garden construction. And Henry David Thoreau's Walden, an experiment in construction and cultivation made in explicit tension with, if not resistance to, the categories and expectations (open full item for complete abstract)

Committee: Leo Coleman (Advisor); Philip Armstrong (Committee Member); Bernhard Malkmus (Committee Member) Subjects: Agriculture; Comparative Literature; Cultural Anthropology; Environmental Studies; Landscaping; Literature; Philosophy

PHD, Kent State University, 2014, College of Arts and Sciences / Department of Geography

Structured into three, interrelated projects, this dissertation is organized under the research themes of climate change and human mortality responses associated with heat and cold events. Using diverse, methodologies which incorporate spatiotemporal variability into seasonal definitions, consistent results were found pertaining to seasonal climate change. Climatological data for 60 U.S. locations was chosen for a lengthy period of record (1948 – 2012), and despite the various delineation methods, results generally indicate earlier starts to summer while winters have become shorter. Using percentile thresholds of daily mean apparent temperature, heat, extreme heat, cold, and extreme cold events (anomalous temperature events or ATEs) were defined and analyzed. In addition to increased frequency and duration, heat and extreme heat events have started earlier over the course of the year since 1948. Conversely, cold and extreme cold have shown the opposite with less frequent, shorter, and later occurring events taking place. While not directly explored, a relationship with ATEs and large-scale teleconnection patterns such as El Nino seems to exist. In bioclimatological research, human health responses have been associated with duration, intensity, and seasonal timing. When comparing mortality responses, a relatively unexplored method in climatology was introduced. More common in epidemiological research, a distributed lag non-linear model (DLNM) assessed the delayed, non-linear responses associated with environmental outcomes. In regards to both heat and cold events, greater risk was associated with early season events compared to later occurring ones. Elevated thresholds of extreme heat and extreme cold showed higher risks when compared to less extreme events. Geographic variability was also shown with higher risks for heat-related mortality in more northern locations while cold-related risks were higher in locations less accustomed to heat. Comparing mor (open full item for complete abstract)

Committee: Scott Sheridan (Advisor); Tom Schmidlin (Committee Member); Andrew Curtis (Committee Member); Lynette Phillips (Committee Member); Ellen Glickman (Committee Member) Subjects: Climate Change; Geography; Public Health

MPH, University of Cincinnati, 2011, Medicine: Public Health - Leadership, Management and Policy

Background: Limited data are available in Honduras describing the etiology and seasonality of childhood acute respiratory infections (ARIs), and better data may lead to improved therapeutic and preventative strategies. Objective: We conducted a prospective sentinel clinic surveillance study to determine the viral etiology of ARIs in rural Honduran children less than 5 years of age to characterize the spectrum and seasonality of viruses associated with acute respiratory infections. Methods: We gathered data on age, sex, medical history, symptoms, demographics, geographic setting, vital signs, and physical exam findings. Nasopharyngeal samples were obtained via flocked swab and shipped to the U.S. in both universal transport medium (UTM) on dry ice and PrimeStore® nucleic acid stabilizing buffer at room temperature. Samples were tested for 14 respiratory viruses using the Luminex Diagnostics polymerase chain reaction (PCR) respiratory viral panel (RVP ID-TagTM). Results: 267 samples were collected from February 2010 – March 2011; 13.9% were positive for influenza, 7.9% for human metapneumovirus, 7.5% for respiratory syncytial virus (RSV), 7.1% for parainfluenza and 2.2% for adenovirus. At least one virus was identified in 194 (72.7%) cases, of which 16 (6.0%) were co-infections. Influenza rose from 1.8% of isolates in February through June to 25.7% of isolates in July through October. No cases of influenza were identified from November 2010 through February 2011. Influenza was present for 5 out of 12 months, and influenza correlated with monthly rainfall in millimeters (R² = 0.2857). Including all tested respiratory viruses except enterovirus/rhinovirus, the presence of a respiratory virus positively correlated with average monthly precipitation (R² = 0.2863). UTM and PrimeStore® results for influenza correlated well (K = 0.767, p<0.0001). Conclusions: These unique results suggest that the spectrum of viruses in rural Honduran children is similar to those found in (open full item for complete abstract)

Committee: William Mase PhD (Committee Chair); Charles Schubert MD (Committee Member); Mark Steinhoff MD (Committee Member) Subjects: Surgery

PhD, University of Cincinnati, 2007, Business Administration : Accounting

This paper explores the economic relevance of the small firm/January effect by examining whether small-firm January returns are positively correlated with contemporaneous accounting earnings. Employing an empirical specification derived from the returns-earnings model set forth by Ohlson (1995) and Feltham and Ohlson (1995), this paper provides evidence that for the second, third and fourth quarters associations between the quarter's first-month returns and the corresponding quarterly earnings are significantly positive. In contrast, the relationship between January returns and first quarter earnings is significantly negative. A novel sample partition which separates small firms that do not experience a January effect from those that do shows that only “January effect” firms exhibit this curious negative relationship between returns and earnings. Results are robust to alternative model specifications. Evidence that January returns are not positively related to contemporaneous accounting earnings calls into question the economic relevance of this market anomaly.

Committee: Dr. Jens Stephan (Advisor) Subjects: Business Administration, Accounting

Doctor of Philosophy, The Ohio State University, 2012, Economics

In my first chapter, ”Unemployment Benefits in a Three State Model of Employment Flows,” I evaluate the welfare effects of unemployment insurance in an incomplete insurance framework where individuals face both employment and earnings risk. I extend the aggregate labor market model of Krusell et al (2011) to include an unemployment insurance (UI) program. The model UI program is similar to UI in the United States and includes a 50 percent replacement rate of income up to a benefit cap, a finite duration of benefits, limited eligibility, and an imperfectly monitored job search requirement. I calibrate the model to match the aggregate labor market moments and flows as well as the size and scope of UI in the United States. The model UI features, especially limited eligibility, limit the steady state welfare effects of UI. As a result, removing UI from the model leads to only a 0.1 percent consumption-equivalent increase in average welfare. The welfare effects are eight times larger when all job losers are eligible for UI. I also find that the moral hazard created by the imperfectly monitored job search requirement and the finite duration of unemployment benefits lead to a spike in the employment hazard of benefit recipients at their benefit expiration, which is consistent with the empirical findings. In contrast, if benefits are uncapped, the overall rate at which benefit recipients search for work is halved in the first two months after a layoff as compared to the baseline model. Thus, modeling the effects of UI in the United States on welfare and individuals' labor supply decisions requires careful modeling of the structure of UI benefits. Recent empirical evidence suggests that the real response of the economy to a monetary shock is seasonally dependent. In my second chapter, ”Seasonality in a Menu Cost Model,” I introduce a seasonal fluctuation into a menu cost model to examine the model's ability to produce an empirically consistent seasonal cycle and a seasonally (open full item for complete abstract)

Committee: Aubhik Khan PhD (Advisor); Paul Evans PhD (Committee Member); Julia Thomas PhD (Committee Member) Subjects: Economics

Doctor of Philosophy, The Ohio State University, 2008, Neuroscience

In this dissertation, I will consider the consequences (physiological, behavioral, and susceptibility to injury) associated with adaptations to both changing biological times and alterations in the social environment. To that end This dissertation is divided into three sections. Section I (chapters 2 and 3) describe a series of experiments that investigate how the social environment regulates inflammatory and behavioral responses to acute administration. Those experiments were designed to determine how animals parse competing behavioral and physiological priorities in order to maximize fitness and survive infection. Section II (chapters 4 and 5) describe the first photoperiodism experiments in this dissertation (see below). Briefly, photoperiodism is the use of day length to regulate seasonal changes in physiology and behavior. Cell-mediated immune responses are typically enhanced in short winter-like day lengths. These experiments were designed to address the role of photoperiod exposure early in life and also the modulatory effects of social housing on photoperiod-mediated changes in the immune system. Section III (chapters 6-9) includes four experiments that investigated temporal and social factors that regulate functional outcomes following cardiac arrest and cardiopulmonary resuscitation. This final set of experiments was conducted to describe and investigate natural fluctuations in ischemic outcomes. I investigated ischemic outcomes at different times of day (chapter 6), after differential social housing (chapter 7), and after sleep deprivation (chapter 8). All of these experiments focused on the role of social and temporal variables in the regulation of inflammatory responses to ischemia.

Committee: Randy Nelson (Advisor); Courtney A Devries (Committee Member); Gary Berntson (Committee Member); Georgia Bishop (Committee Member); Courtney Lynch (Committee Member) Subjects: Biomedical Research

Doctor of Philosophy, The Ohio State University, 2008, Physics

Ecological systems such as forest and lakes can exhibit multiple stable states, abrupt transitions and self-organization as a control parameter is varied. Understanding the dynamics of these systems and devising easily quantifiable measures with predictive capabilities using the theoretical tools of stochastic dynamics and nonequilibrium statistical physics form the focus of this thesis.We study simple ecological models with no spatial degrees of freedom, that show a catastrophic transition as a control parameter is varied and propose a novel early warning signal that exploits two ubiquitous features of ecological systems: nonlinearity and large external fluctuations. It is shown that changes in asymmetry in the distribution of time series data, quantified by changing skewness, is an early warning signal of impending regime shifts. Using simple analytical calculations, model simulations that mimic field measurements and an analysis of real data from abrupt climate change in the Sahara, we study the feasibility of skewness calculations using data available from routine monitoring. We consider a spatially explicit model of collapse of vegetation in one and two spatial dimensions. An analytical calculation based on the mean-field approximation shows that spatial variance and spatial skewness (with an appropriate sign) increase as one approaches the threshold of vegetation collapse. Our numerical calculations show that an increasing spatial variance in conjunction with a reversal in the initial changing trend of spatial skewness is a superior indicator of an impending spatial ecological regime shift when spatially explicit data are available. These results are shown to hold under several different dispersal kernels such as Gaussian, fat tailed and Cauchy. Vegetation in semi-arid regions exhibits striking spatial patterns. Theoretical models often ignore the strong fluctuations in parameters such as those arising from seasonality. We present a fully seasonal rainfall mod (open full item for complete abstract)

Committee: C Jayaprakash PhD (Committee Chair); David Stroud PhD (Committee Member); Dick Furnstahl PhD (Committee Member); Michael Poirier PhD (Committee Member) Subjects: Ecology; Physics

Doctor of Philosophy, The Ohio State University, 2006, Neuroscience

Seasonal adaptations have evolved in animals and are believed to promote survival and reproduction through yearly changes in the environment. These seasonal responses are physiological, morphological, and behavioral and are coordinated by day length (photoperiod) information in non-tropical rodents. In the laboratory, short days promote a winter phenotype, whereas long days promote a summer phenotype. This dissertation was designed to examine the effects of photoperiod on adult plasticity of physiology, brain, and behavior in male white-footed mice (Peromyscus leucopus) that may represent seasonal adaptations to the changing environment. Recent evidence suggests that significant plasticity occurs in adult systems including the central nervous system. The first studies examined the effects of photoperiod on angiogenesis in the periphery and the brain. Short days altered expression of angiogenesis genes in testes and brain and decreased cerebral blood flow compared with long days. The next set of studies was based on the finding that short days decreased brain mass and impaired spatial learning and memory compared with long days. The hippocampus is involved in spatial learning and memory and is one of the few brain regions associated with significant adult plasticity. Short days decreased hippocampal volume, altered hippocampal dendritic spine density, modified the effects of learning experience on neurogenesis, and dampened long-term potentiation compared with long days. Photoperiod alters concentrations of various hormones, some of which affect the hippocampal morphology and function. Testosterone reversed the short-day impairment of spatial learning and memory indirectly of hippocampal steroid receptors, but did not affect long-day performance. Corticosterone altered spatial learning and memory depending on photoperiod and duration of exposure and short days altered the hypothalamic-pituitary-adrenal axis compared with long days. The effects of photoperiod on the o (open full item for complete abstract)

Committee: Randy Nelson (Advisor) Subjects:

Doctor of Philosophy, The Ohio State University, 2005, Psychology

Seasonal mood disorder (SMD) is likely prevalent among children and adolescents; however, there are few empirical investigations of pediatric SMD in the literature. To contribute to the field, the current study investigates the seasonality of mood and behavior among children and adolescents using longitudinal data collected from 1987 to 1998. One hundred eleven youths diagnosed with depression, 369 bereaved youths, 129 community controls, and their parents completed individual assessments at baseline, five, thirteen, and twenty-five months later. Assessment materials include several measures of depressive symptoms and diagnostic instruments. Multilevel analyses were conducted using MlwiN software. According to both parent- and child-report, youths from all three groups earn significantly higher total scores on measures of depression during the winter than the summer. On the other hand, significant seasonal effects do not arise for a measure of overall psychopathology. This implies that seasonality is limited to mood disorders. While this seasonal effect is significant, actual changes of mean scores on measures of depression from the summer to the winter are minimal, suggesting that season may have little affect on the mood and behavior for the majority of participants from each group. It is uncertain whether a few highly seasonal participants influence the mean changes between summer and winter or whether each group as a whole experiences very mild seasonal changes. In either case, the finding that depressed, bereaved, and community controls show similar average levels of seasonality supports the dual vulnerability model of SMD, which posits that seasonality and propensity toward depression are independent. Data collected from the youths, themselves, suggest that seasonality shown on measures of depression arise from seasonal changes in atypical vegetative symptoms as opposed to cognitive or affective symptoms. This is consistent with the hypotheses. However, data c (open full item for complete abstract)

Committee: Mary Fristad (Advisor) Subjects: Psychology, Clinical

Doctor of Philosophy, The Ohio State University, 2003, Anthropology

Health is a complex construct dependent on socio-cultural, economic and biological factors. The concept of health is very complicated; the expression of health is the result of the interaction of many biological, economic and cultural factors and includes both psychological and biological well-being. Health is not static. Humans are plastic, able to respond both behaviorally and biologically to stressors that threaten their well-being. The range of adaptive responses is highly variable and has long been an area of interest to Anthropologists. Human life history responds to stressors. Among women, the reproductive span is particularly sensitive to the environment. Fertility and its biological correlate fecundity are responsive to external stressors and often reflect the health and well-being of women in their environment. This research documents how differences in social settings, health, physical environment and biology interact and affect urban Bhutia women in Sikkim, India and contribute to the low fertility in this population. Individual variables such as nutrition, workloads and health have been found to significantly influence female fecundity by altering the levels of the hormones that make reproduction possible. While the contributions of these individual factors have been studied in detail, very little is known about the interactive effects of these three variables. Moreover, these three variables are significantly impacted by the changes associated with economic and social development and urbanization. Results of this study show that seasonal climatic variation significantly affects urban Bhutia women, their health and well-being. Measurements of energy balance, health, psychosocial stress and fecundity reflect changes in environment. However, responses of these variables to seasonal stressors were not consistent. Seasonal patterns in changes in energy balance, health status and fecundity were unique. Results of this study suggest that health measures influ (open full item for complete abstract)

Committee: Douglas Crews (Advisor) Subjects: Anthropology, Physical

Master of Science, Miami University, 2003, Zoology

Several investigators have documented a negative density-area relationship (i.e. higher population densities in smaller fragments) for Peromyscus leucopus (the white-footed mouse). The purpose of this thesis is to investigate if high densities of P. leucopus are consistent among seasons and if higher densities may be due to greater reproduction, as a result of higher food availability, in small than large fragments. Observations of nest box use suggest that relative density and reproduction in small and large fragments differ among seasons. Higher densities in small than large fragments were only documented during the fall season. Observations of foraging patch use combined with reproductive data suggest that greater food availability in the edge may allow greater reproduction and thus contribute to higher densities in small fragments. Dense edge vegetation may be the primary contributor to greater food availability, although there is some evidence that there may be fewer competitors in small fragments.

Committee: Douglas Meikle (Advisor) Subjects:

MS, University of Cincinnati, 2013, Arts and Sciences: Geology

The response of ice sheets to climate change is of concern because of meltwater introduction to the oceans raising sea level. Yet it is uncertain how the Laurentide Ice Sheet (LIS) responded to the widely studied Younger Dryas (YD) cold interval (~12.9-11.6 cal ka BP). In northwestern Wisconsin and the Upper Peninsula of Michigan, two sites record advances of the LIS before and near the end of the YD. The Two Creeks (~13.7 cal ka BP) and Lake Gribben (~11.6 cal ka BP) forest beds indicate that the ice sheet margin was between those sites during the YD. New geomorphic mapping and synthesis of existing and new chronology for the ice margin, document activity of the ice sheet during the YD. Combined, these data indicate that the ice sheet margin had at least six stationary positions during retreat through the YD interval and a readvance after the YD. When this pattern is compared to the isotopic record from the Greenland ice core, an apparent conflict arises. The ice sheet is retreating at a time generally thought to be cold and correlating with glacial advances. This may imply that seasonality and the corresponding warmer summers during the YD controlled the ice sheet response. Alternatively they may imply caution is needed when interpreting the ice core record.

Committee: Thomas Lowell Ph.D. (Committee Chair); Timothy Gordon Fisher Ph.D. (Committee Member); David Byer Nash Ph.D. (Committee Member) Subjects: Geology

PHD, Kent State University, 2010, College of Business and Entrepreneurship, Ambassador Crawford / Department of Management and Information Systems

The traditional newsvendor model results in a decision to reorder an item whenever the expected profit from the reorder is positive. Candidates for reorder include all items selling more quickly than had been anticipated during preseason forecasts and ordering. Retailers must also decide how to allocate shelf space in order to optimize store profit; any item reordered must be the most profitable option among all items competing for the same shelf space. Overall store profit calculations must incorporate the impact on sales of related items, the cost of stock outs, and characteristics of the reordered item. Seasonal products' abbreviated sales windows and style products' short life cycles add urgency and complexity to the reorder decision. Lack of product availability may limit how much of the most profitable item can be ordered; in these cases, the next most profitable item is the most likely candidate for the remaining available shelf space. In this paper we extend the work of Corstjens and Doyle (1981) and Gallego and Moon (1993) and develop a model encompassing each of these elements: the newsvendor reorder decision, seasonal goods, style goods, multiple discounts, shortage costs, expediting, and shelf space allocation incorporating cross product elasticity. The shelf space allocation is an extension of the knapsack problem requiring not only that the profit calculations include effects on sales of related items, but that the requisite space to hold these related items is available. The model is implemented and validated as a decision support system (DSS). Corstjens and Doyle's (1981), Gallego and Moon's (1993), and the classic newsvendor models are also implemented in the DSS for comparison purposes. Scenario analysis, testing the model's sensitivity of the decision to managers' assumptions, is incorporated as are tools to derive the range of values for which the decision is valid.

Committee: Marvin Troutt PhD (Committee Chair); Alan Brandyberry PhD (Committee Member); Alfred Guiffrida PhD (Committee Member); Milton Harvey PhD (Committee Member) Subjects: Business Administration; Information Systems; Management; Marketing