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Chen, WeiDeveloping a Framework for Geographic Question Answering Systems Using GIS, Natural Language Processing, Machine Learning, and Ontologies
Doctor of Philosophy, The Ohio State University, 2014, Geography
Geographic question answering (QA) systems can be used to help make geographic knowledge accessible by directly giving answers to natural language questions. In this dissertation, a geographic question answering (GeoQA) framework is proposed by incorporating techniques from natural language processing, machine learning, ontological reasoning and geographic information system (GIS). We demonstrate that GIS functions provide valuable rule-based knowledge, which may not be available elsewhere, for answering geographic questions. Ontologies of space are developed to interpret the meaning of linguistic spatial terms which are later mapped to components of a query in a GIS; these ontologies are shown to be indispensable during each step of question analysis. A customized classifier based on dynamic programming and a voting algorithm is also developed to classify questions into answerable categories. To prepare a set of geographic questions, we conducted a human survey and generalized four categories that have the most questions for experiments. These categories were later used to train a classifier to classify new questions. Classified natural language questions are converted to spatial SQLs to retrieve data from relational databases. Consequently, our demo system is able to give exact answers to four categories of geographic questions within an average time of two seconds. The system has been evaluated using classical machine learning-based measures and achieved an overall accuracy of 90% on test data. Results show that spatial ontologies and GIS are critical for extending the capabilities of a GeoQA system. Spatial reasoning of GIS makes it a powerful analytical engine to answer geographic questions through spatial data modeling and analysis.

Committee:

Eric Fosler-Lussier, Dr. (Committee Member); Rajiv Ramnath, Dr. (Committee Member); Daniel Sui, Dr. (Committee Member); Ningchuan Xiao, Dr. (Committee Chair)

Subjects:

Cognitive Psychology; Computer Science; Geographic Information Science; Geography; Information Science; Information Systems; Information Technology; Language

Keywords:

geographic information system; GeoQA; geographic question answering framework; geolinguistics; spatial ontologies;

Bedocs, Justin ANames and Geographic Features: An Internship with the U.S. Geological Survey
Master of Environmental Science, Miami University, 2016, Environmental Sciences
Place names are vital to orienting ourselves in the world. In ancient times, people must have had names for places like hunting grounds or berry groves. This act of naming roughly delineates geographic features which can be revisited and described to others, affixing an added cultural meaning to that place. Place naming has since come a long way. Official place names for the United States and its territories are managed by the United States Geological Survey (USGS), National Geospatial Technical Operations Center (NGTOC). This report details my experience working in the Geographic Names Unit. As a Pathways Career Intern, my main duties were to manage the Geographic Names Information System (GNIS), a database containing official place names for features outlined on federal topographic maps. Most of the work involved duplicate names; an issue where there are two name records for one feature, often indicating that one record is a copy and should be deleted. Sometimes the two records were not copies, and the correct locations were identified by visually analyzing historic and recent maps. The coordinates were then updated respectively in the GNIS. I gained valuable experience reading topographic maps, identifying features and managing a large database of geographic names.

Committee:

Robbyn Abbitt, MS (Committee Chair); Suzanne Zazycki, JD (Committee Member); Mark Allen Peterson, PhD (Committee Member)

Subjects:

Cartography; Computer Science; Cultural Anthropology; Earth; Environmental Science; Geographic Information Science; Geography; History; Information Science; Information Technology; Language; Native American Studies

Keywords:

Places; Names; Place Names; Geographic Features; Geography; Cultural Anthropology; Linguistics; Topography; Naming Disputes; Denali; Sense of Belonging; Community; Topographic Maps; Stakeholder Groups; GNIS; Geographic Names Information System

Woodard, John RBUILDING AN ENTERPRISE GEOGRAPHIC INFORMATION SYSTEM FROM AN ENTERPRISE ARCHITECTURE FOUNDATION
MDS, Kent State University, 2017, School of Digital Sciences
The information explosion of today’s society has been paralleled by the growth of Geographic Information Systems (GIS). Geographic Information Systems (GIS) have been leveraged by many fields outside the discipline of geography. Historians have successfully created a digital version of the Battle of Little Bighorn for real-time analysis by creating an artifact location database and then mapping the battle’s progress with GIS. Public Health and Emergency Management officials have used GIS to predict, track, and respond to disease outbreaks around the world. GIS has become a valuable tool to government, industry, and business leaders. The growth and development of many GIS systems has followed an ad hoc pattern. Early successes results in the hiring of a person dedicated to establishing a GIS department or enterprise system that provides services and programs to all levels of the organization. Although the system shares folders, files, data and results of analysis, it is not a true enterprise system because it lacks organization and focus. GIS Professionals can use Enterprise Architecture (EA) to provide order and strategy for chaotic Enterprise GIS systems. This paper is based on research that identified a knowledge gap between Enterprise GIS and Enterprise Architecture. This knowledge gap lies in the fundamental differences in the systems application. The main goal of an Enterprise GIS is to provide access to system tools, data, and analysis to anyone within the organization. Current Enterprise GIS is concerned about spreading GIS philosophy and considers supporting business goals to be a secondary function. This paper provides research that demonstrates Enterprise GIS systems can benefit from Enterprise Architecture ideas and methods. It also guides the reader through the process of using elements of Enterprise Architecture to build an Enterprise GIS system. The final conclusion is that Enterprise GIS can be improved by incorporating the ideas of Enterprise Architecture.

Committee:

Robert Walker (Committee Chair)

Subjects:

Computer Science; Geographic Information Science; Information Science

Keywords:

GIS, Enterprise Architecture, Information Architecture, geospatial,geographic information system,

Fontanella, ShaunIndexing Geographic Information Using the Domain Name System
Master of Science, The Ohio State University, 2012, Environment and Natural Resources
There is a large amount of geographic information (GI) being collected every day all over the world. Governments, the traditional collectors of GI, have a multitude of institutional barriers preventing them from being able to nimbly collect and index GI. This thesis proposes a new and open system that indexes GI using an index built on top of the already ubiquitous Domain Name System called Geographic Domain Name System (GDNS). The GDNS uses a combination of the latitude and longitude of the centroid of a parcel to create a DNS hostname. This hostname points to the source of authoritative data on the internet. A web map acts as a visual search device of the hostnames. A design science research methodology is used to build and critique the thesis software artifacts.

Committee:

Earl Epstein, PhD (Advisor); Ola Ahlqvist, PhD (Committee Member); Brian Slater, PhD (Committee Member)

Subjects:

Geographic Information Science; Geography; Information Science; Information Systems; Information Technology

Keywords:

DNS; Geographic Information; Domain Name System; GDNS

Mierzwiak, Sara M.The Development of the Contaminant Exceedance Rating System (CERS) for Comparing Groundwater Contaminant Data
Master of Arts, University of Toledo, 2012, Geography

The typical approach to mapping groundwater contaminant plumes involves drawing plume contours out to each contaminant’s site-specific cleanup criterion. Cleanup criteria differ between contaminants, sites and U.S. states. For this reason, it is difficult to determine which monitoring wells, plumes and sites are most contaminated within a given area or region. For the same reason, it is also difficult to determine which individual contaminant is most concentrated within a single monitoring well.

The Contaminant Exceedance Rating System (CERS) was developed to address these issues by normalizing groundwater contaminant data against their site-specific cleanup criteria. Each contaminant’s laboratory analytical result is divided by its respective site-specific cleanup criterion and the result is a unitless ratio which is then compared against other CERS Values. The CERS Values are then ranked into a set of CERS Ranking Categories for data grouping purposes and ease of mapping.

The CERS was successfully implemented utilizing data from the Former Wurtsmith Air Force Base (WAFB) in Oscoda, Michigan (provided by the Air Force Center for Engineering and the Environment[AFCEE]). Basewide groundwater volatile organic compound (VOC) data from Summer/Fall 2009 was utilized. ESRI┬┐┬┐ ArcGIS Version 10.0 was used to map the resultant CERS Values, symbolized by their Ranking Categories. By implementing the CERS, the following were successfully determined for this data: the most concentrated contaminant in each sample, the most contaminated well(s) within each site, the most contaminated wells on the entire base, and the most contaminated plumes on the base.

It is recommended that the CERS be further implemented using additional temporal data from the Former WAFB. It is also recommended that the CERS be implemented using contaminant data from other Department of Defense (DoD) installations. The CERS could allow for comparison of maximum degree of contamination between entire installations, with the overall intent being to assist in the DoD-wide remedial funding prioritizing process. CERS Values could also be used to track remedial progress over time when implemented using temporal data. The CERS does not take into consideration such factors as toxicity or receptor analysis. This document serves as a manual for implementation of the CERS using contaminant data from other sites.

Committee:

Patrick Lawrence, PhD (Committee Chair); Peter Lindquist, PhD (Committee Member); Robert Beckwith, PG (Committee Member)

Subjects:

Chemistry; Environmental Economics; Environmental Management; Environmental Science; Environmental Studies; Geochemistry; Geographic Information Science; Geography; Hydrologic Sciences; Hydrology; Information Science; Information Systems; Natural Resource Management; Water Resource Management

Keywords:

groundwater; contamination; monitoring wells; water; pollution; pollutants; ranking; categories; remediation; Department of Defense; Air Force; AFCEE; DoD; Wurtsmith Air Force Base; Air Force Base; GIS; Geographic Information Systems; ArcGIS; ESRI; VOC

Hall, Alexander EdmundEffects of Mulitple Small Impoundments on Hydrologic Regime in Southwestern Ohio
Master of Arts, Miami University, 2012, Geography
Water is used to drink, water crops, generate power, as well as for many other purposes. Today more than ever anthropogenic effects on the hydrologic cycle are being studied, weighed, and considered. There are an estimated 2.6 million small water bodies in the continental United States (Renwick et al. 2005). Despite this large number, they are just beginning to be studied, and their impact on the hydrologic cycle is still largely unknown. A watershed in Southwestern Ohio was modeled to determine the effect of small impoundments on hydrologic regime on a storm-event scale using HEC-HMS. The impoundments have an overall minimal impact on regime. The counteracting forces of the storage effect of impoundments and their increase in surface runoff due to loss of permeable surface area are nearly balanced due to their topographic positions in the watershed.

Committee:

William Renwick, PhD (Committee Chair); John Maingi, PhD (Committee Member); Robbyn Abbitt (Committee Member)

Subjects:

Geographic Information Science; Geography; Hydrology

Keywords:

Hydrology; HEC-HMS; Ohio; HEC-geoHMS

Barsai, GaborDATA REGISTRATION WITHOUT EXPLICIT CORRESPONDENCE FOR ADJUSTMENT OF CAMERA ORIENTATION PARAMETER ESTIMATION
Doctor of Philosophy, The Ohio State University, 2011, Geodetic Science and Surveying

Creating accurate, current digital maps and 3-D scenes is a high priority in today’s fast changing environment. The nation’s maps are in a constant state of revision, with many alterations or new additions each day. Digital maps have become quite common. Google maps, Mapquest and others are examples. These also have 3-D viewing capability. Many details are now included, such as the height of low bridges, in the attribute data for the objects displayed on digital maps and scenes. To expedite the updating of these datasets, they should be created autonomously, without human intervention, from data streams. Though systems exist that attain fast, or even real-time performance mapping and reconstruction, they are typically restricted to creating sketches from the data stream, and not accurate maps or scenes. The ever increasing amount of image data available from private companies, governments and the internet, suggest the development of an automated system is of utmost importance.

The proposed framework can create 3-D views autonomously; which extends the functionality of digital mapping. The first step to creating 3-D views is to reconstruct the scene of the area to be mapped. To reconstruct a scene from heterogeneous sources, the data has to be registered: either to each other or, preferably, to a general, absolute coordinate system. Registering an image is based on the reconstruction of the geometric relationship of the image to the coordinate system at the time of imaging. Registration is the process of determining the geometric transformation parameters of a dataset in one coordinate system, the source, with respect to the other coordinate system, the target. The advantages of fusing these datasets by registration manifests itself by the data contained in the complementary information that different modality datasets have. The complementary characteristics of these systems can be fully utilized only after successful registration of the photogrammetric and alternative data relative to a common reference frame. This research provides a novel approach to finding registration parameters, without the explicit use of conjugate points, but using conjugate features. These features are open or closed free-form linear features, there is no need for a parametric or any other type of representation of these features The proposed method will use different modality datasets of the same area: lidar data, image data and GIS data. There are two datasets: one from the Ohio State University and the other from San Bernardino, California.

The reconstruction of scenes from imagery and range data, using laser and radar data, has been an active research area in the fields of photogrammetry and computer vision. Automatic, or just less human intervention, would have a great impact on alleviating the “bottle-neck” that describes the current state of creating knowledge from data. Pixels or laser points, the output of the sensor, represent a discretization of the real world. By themselves, these data points do not contain representative information. The values that are associated with them, intensity values and coordinates, do not define an object, and thus accurate maps are not possible just from data. Data is not an end product, nor does it directly provide answers to applications, although implicitly, the information about the object in question is contained in the data. In some form, the data from the initial data acquisition by the sensor has to be further processed to create useable information, and this information has to be combined with facts, procedures and heuristics that can be used to make inferences for reconstruction. To reconstruct a scene perfectly, whether it is an urban or rural scene, requires prior knowledge, heuristics. Buildings are, usually, smooth surfaces and many buildings are blocky with orthogonal, straight edges and sides; streets are smooth; vegetation is rough, with different shapes and sizes of trees, bushes. This research provides a path to fuse data from lidar, GIS and digital multispectral images and reconstructing the precise 3-D scene model, without human intervention, regardless of the type of data or features in the data. The data are initially registered to each other using GPS/INS initial positional values, then conjugate features are found in the datasets to refine the registration. The novelty of the research is that no conjugate points are necessary in the various datasets, and registration is performed without human intervention.

The proposed system uses the original lidar and GIS data and finds edges of buildings with the help of the digital images, utilizing the exterior orientation parameters to project the lidar points onto the edge extracted image/map. These edge points are then utilized to orient and locate the datasets, in a correct position with respect to each other.

Committee:

Alper Yilmaz, PhD (Advisor); Carolyn Merry, PhD (Committee Member); Alan Saalfeld, PhD (Committee Member); Ron Li, PhD (Committee Member)

Subjects:

Civil Engineering; Computer Engineering; Geographic Information Science

Keywords:

automatic registration; 3D reconstruction; lidar; GIS; digital image; point free registration

Raje, SatyajeetResearchIQ: An End-To-End Semantic Knowledge Platform For Resource Discovery in Biomedical Research
Master of Science, The Ohio State University, 2012, Computer Science and Engineering

There is a tremendous change in the amount of electronic data available to us and the manner in which we use it. With the on going “Big Data” movement we are facing the challenge of data “volume, variety and velocity.” The linked data movement and semantic web technologies try to address the issue of data variety. The current demand for advanced data analytics and services have triggered the shift from data services to knowledge services and delivery platforms. Semantics plays a major role in providing richer and more comprehensive knowledge services.

We need a stable, sustainable, scalable and verifiable framework for knowledge-based semantic services. We also need a way to validate the “semantic” nature of such services using this framework. Just having a framework is not enough. The usability of this framework should be tested with a good example of a semantic service as a case study in a key research domain. The thesis addresses two research problems.

Problem 1: A generalized framework for the development of end-to-end semantic services needs to be established. The thesis proposes such a framework that provides architecture for developing end–to–end semantic services and metrics for measuring its semantic nature.

Problem 2: To implement a robust knowledge based service using the architecture proposed by the semantic service framework and its semantic nature can be validated using the proposed framework.

ResearchIQ, a semantic search portal for resource discovery in the biomedical research domain, has been implemented. It is intended to serve as the required case study for testing the framework. The architecture of the system follows the design principles of the proposed framework.

The ResearchIQ system is truly semantic from end-to-end. The baseline evaluation metrics of the said framework are used to prove this claim. Several key data sources have been integrated in the first version of the ResearchIQ system. It serves as a framework for semantic data integration in the biomedical domain. It can be used as a platform for development and support of a variety of semantic services and applications in the biomedical domain.

A large part of this thesis is devoted to the details regarding the ResearchIQ project. The document is intended as a report of the ResearchIQ project as a successful implementation of an end-to-end semantic framework.

Committee:

Jayashree Ramanathan, PhD (Advisor); Rajiv Ramnath, PhD (Committee Member)

Subjects:

Biomedical Research; Computer Engineering; Computer Science; Information Science; Information Systems; Information Technology

Keywords:

Semantic Web; Knowledge-based Systems; Ontology; Semantic Search; ETL; Data Integration; Biomedical Informatics

Li, JunSpatial-temporal modeling of ambient PM concentration in Ohio and Franklin County
Master of Arts, The Ohio State University, 2010, Geography

PM2.5 (Particles up to 2.5 µm in diameter) have a wide variety of health effects on human beings, and are found to be related to different kinds of traffic and land use factors. The land use regression (LUR) model has been used in many studies to model air pollution concentration across the world. However, the LUR model does not incorporate the temporal variation, so it can hardly be used in epidemiological studies.

To undertake analysis at a finer spatial and temporal resolution, this paper explores the monthly, daily and hourly PM concentration in Ohio and Franklin County. At the large scale of the Ohio state, PM concentrations within different seasons, months and days are explored and predicted. And at the smaller scale of Franklin County, PM concentrations at 24 hours of 10 days in 2008 are predicted and used to estimate the journey-time exposure when people are moving around Franklin County. To incorporate both the time-varying and time-invariant factors in one regression model, the Generalized Additive Model (GAM), of which the relationship between response and independent variables is cubic spline rather than linear, is used to estimate the short-term variations in air pollution. In the paper, the time-varying factors include meteorological and traffic variables while the time-invariant factors include different land use type, transportation, population density, major roads and highway information.

This paper is the first study that undertakes spatially complex and temporally dynamic time-space modeling in Ohio.

Committee:

Mei-po Kwan (Advisor); Desheng Liu (Advisor); Ningchuan Xiao (Committee Member)

Subjects:

Geographic Information Science

Keywords:

spatial temporal modeling; particulate matter; Ohio

Deshpande, Shubhanan V.Knowledge-based Cyberinfrastructures for Decision Making in Real-World Domains
Master of Science, The Ohio State University, 2011, Computer Science and Engineering
Contemporary domain software such as gaming, training and simulation software successfully captures objects and interactions in the corresponding real-world domains to enable learning and decision-making. However, such systems are designed, developed and operated in isolation, despite the fact that they have objects and interactions that are strikingly similar in the real world. Their features do not exploit commonality, and hence, are a result of independent characterization of a subset of underlying reality. Such disjoint domain modeling has lead to specialized, but isolated software features that ought to be connected as the domains in real world intrinsically are. In this thesis, we propose a cyberinfrastructure framework that allows domain objects, interactions and decisions, and derived knowledge to be inter-related using shared upper ontology. This allows multiple simulation, gaming, and collaboration features to be composed and utilized in new ways to lead to decisions and learning that is more consistent with the real-world. The research enables specialized, dispersed communities of practice to easily leverage knowledge from other related real-world collaborations and solutions, while they continue to collaborate in their own domains of interest. This thesis motivates and develops a framework that is used for connecting real-world domain software at multiple levels – from the domain model to implementation constructs. It implements a reference architecture prototype and applications that illustrate making the tacit knowledge explicit for sharing and reusability. It also sets directions and some leads for the future research.

Committee:

Jayashree Ramanathan, PhD (Advisor); Rajiv Ramnath, PhD (Committee Member); Ola Ahlqvist, PhD (Committee Member)

Subjects:

Computer Engineering; Computer Science; Information Science; Information Systems; Information Technology

Keywords:

cyberinfrastructure; decision-making; ontology; shared ontology; domain knowledge

Hoffman, MarcEfficient Software and Hardware Implementations of the H.264 Entropy Encoders
Master of Science (M.S.), University of Dayton, 2011, Engineering
Part 10 of MPEG-4 describes the Advanced Video Coding (AVC) method widely known as H.264. H.264 is the product of a collaborative effort known as the Joint Video Team(JVT). The final draft of the standard was completed in May of 2003, and since then H.264 has become one of the most commonly used formats for compression of high definition video [9]. The entire H.264/AVC encoder is inherently a sequential process, which typically lends itself to a software solution. Within the H.264 Standard, two entropy decoders are discussed. These two lossless encoding methods are known as Context Adaptive Variable Length Coding (CAVLC) and Context Adaptive Binary Arithmetic Coding (CABAC). CAVLC offers the most basic solution, while CABAC provides increased compression rates at a cost in algorithm complexity. For fast encoding of H.264 bit streams, three solutions are presented in this thesis. Two implementations of CAVLC are discussed, including a software and a hardware solution. Finally, a simple implementation of CABAC is proposed.

Committee:

Eric Balster, PhD (Advisor); Frank Scarpino, PhD (Committee Member); Vijayan Asari, PhD (Committee Member)

Subjects:

Computer Engineering; Electrical Engineering; Information Science

Keywords:

H.264; video compression; image processing

Malizia, Richard WalterAnalyzing Niche Stability in Late Ordovician Articulated Brachiopod Species during the Richmondian Invasion
Master of Science (MS), Ohio University, 2011, Geological Sciences (Arts and Sciences)
In this study, the relative niche stability of Late Ordovician articulate brachiopod species from the Cincinnati Arch were analyzed before, during, and after an immigration of extra-basinal taxa into the Cincinnati, OH region, known as the Richmondian Invasion. The primary hypothesis investigated with this project is whether species preserve (niche conservation) or alter (niche evolution) the parameters of their ecological niche during intervals of biotic (invasive regime) vs. abiotic change (gradual environmental change). Ecological niche modeling (ENM), which is a process that utilizes computer-based algorithms to mathematically estimate a species ecological niche was employed to test this hypothesis. Additionally, the efficacy of the ENM program Maxent for use with fossil data was tested against a well established ENM method (GARP). Results indicate that during intervals of gradual change, species conserve the parameters of their ecological niches to higher degrees than during intervals of ecological rapid biotic change, when niche evolution is common.

Committee:

Alycia Stigall (Advisor); Douglas Green (Committee Member); Elizabeth Gierlowski-Kordesch (Committee Member)

Subjects:

Ecology; Geographic Information Science; Geology; Paleoecology; Paleontology

Keywords:

Ecological niche modeling; Maxent; Cincinnatian; Late Ordovician; Invasive species; Niche stability

Lawlor, Sarah E.Using Advanced Land Imager (ALI) and Landsat Thematic Mapper (TM) for the detection of the invasive shrub Lonicera maackii in southwestern Ohio forests
Master of Arts, Miami University, 2011, Geography
Lonicera maackii, an understory invasive shrub, has an extended leaf phenology that can be detected with remote sensing in the fall when the canopy is leafless and the shrub’s leaves are still green. The purpose of this research was to compare how accurately image data from the Advanced Land Imager (ALI) sensor vs. Landsat Thematic Mapper (TM) identify L. maackii. Point intercept sampling was used to quantify L. maackii in 20 woodlots in two counties in southwestern Ohio. Spectral Vegetation Indices (SVIs) were applied to both images for each plot. Field estimated percent cover was regressed on values for each SVI per image to determine the best predictor of L. maackii cover. Cover of L. maackii was better explained by Landsat TM regressions than ALI. TM image results suggest that the ALI image was acquired too late seasonally to accurately detect the invasive shrub. The analysis did not clearly assess ALI for this research.

Committee:

Mary Henry, PhD (Advisor); David Gorchov, PhD (Committee Member); Jerry Green, PhD (Committee Member)

Subjects:

Geographic Information Science; Geography; Physical Geography; Remote Sensing

Keywords:

Advanced Land Imager; Landsat Thematic Mapper; Lonicera maackii, invasive species

Nwaodua, Emmanuel CLast Deglacial Arctic to Pacific Transgressions via the Bering Strait: Implications for Climate, Meltwater Source, Ecosystems and Southern Ocean Wind Strength
PHD, Kent State University, 2013, College of Arts and Sciences / Department of Geology
The main goal of this research is to provide physical evidence of reverse flow(s), from the Arctic to the North Pacific Ocean, after the Last Glacial Maximum (LGM). This is primarily essential to studies concerned with understanding how the fluctuations in strength of the Southern Ocean Wind (SOW), in conjunction with an open Bering Strait, alter the direction of water flow through the Bering Strait. Visible and Near Infrared (VNIR) derivative spectroscopy; quotient normalization and varimax rotated principal component analysis of diffuse spectral reflectance (DSR) measurements from 234 surface core samples and 2 piston cores, in addition to the USGS spectral library, were used to extract and identify these lithological compositions (in order of importance) within the study location. These compositions are chlorite + muscovite; goethite + phycoerythrin + phycocyanin; smectite; calcite+dolomite; and illite + Chlorophyll a. The Geostatistical tool, kriging, was utilized in creating the sedimentary maps of all the components. These maps were used to determine these components' modern spatial patterns. This aided in the evaluation and downcore interpretation of the component most suited for this study. The illite in illite + Chlorophyll a assemblage was deemed to be the appropriate water mass tracer for a reverse flow from the Arctic into the North Pacific; this is because of its prominence and abundance in the Mackenzie River drainage basin and on the west Arctic Sea shelf. The illite denotes these periods of meltwater pulses (MWP): MWP 1A, ~14,600 and 13,800 Cal yrs. BP, separated by the Older Dryas; MWP 1B, ~11,000-9,200 Cal yrs. BP; and MWP 1C, ~8,000 Cal yrs. BP. The timing of these pulses along with previously published data on the Bering Sea shelf and the North Pacific Ocean enabled these deductions: 1) the initial opening of the Bering Strait and the flow direction after the LGM; 2) the source of these meltwater pulses and the mechanism that might drive them through the Strait; 3) the impact of these pulses on climate change; and 4) the effect of these pulses on the Bering Sea shelf ecosystem.

Committee:

Joseph Ortiz (Advisor); Alison Smith (Committee Member); Elizabeth Griffith (Committee Member); John Portman (Committee Member)

Subjects:

Geochemistry; Geographic Information Science; Geology; Geophysics

Keywords:

Arctic; quotient normalization; spectral; Bering Sea; provenance analysis; diffuse spectral reflectance; carbonates; clay minerals; diatoms; meltwater pulse; North Pacific; Bering Strait; Atlantic Meridional Overturning Circulation; climate; ecosystem

Li, BoSupply Chain Inventory Management with Multiple Types of Customers: Motivated by Chinese Pharmaceutical Supply Chains among Others
Doctor of Philosophy, University of Toledo, 2013, Manufacturing and Technology Management
The healthcare industry in both developed and developing economies is facing many challenges in reducing cost and improving service quality. The $860 billion global pharmaceutical industry is one of the most important components of the healthcare system and it plays a vital role in improving the performance of the healthcare system. The pharmaceutical supply chain is an important business component supporting the pharmaceutical industry. At this time, People's Republic of China is placing a great deal of emphasis on improving its pharmaceutical supply chain, thus opening up this research opportunity.

This research begins by studying the Chinese Pharmaceutical Supply Chain (PSC), through an in-depth analysis of a Chinese PSC member followed up by a survey of a few representative members through a questionnaire. Motivated by this initial study of the Chinese PSC and other similar supply chains, we address the inventory problems faced by such supply chains. The supply chains face multiple customer-types with different characteristics defined by price and demand. We investigate both single and multi-period models with different customer-types. In each case, we develop heuristics that find optimal or near optimal inventory strategies. We use computer simulation to investigate the effectiveness of the heuristics. We also develop some general recommendations for the managers of these supply chains.

Committee:

P.S. Sundararaghavan (Committee Co-Chair); Udayan Nandkeolyar (Committee Co-Chair); Jerzy Kamburowski (Committee Member); Yue Zhang (Committee Member); Donald Saftner (Committee Member); Matthew Franchetti (Committee Member)

Subjects:

Applied Mathematics; Asian Studies; Business Administration; Business Costs; Entrepreneurship; Geographic Information Science; Health Care Management; International Relations; Management; Marketing; Operations Research; Pharmaceuticals; Sustainability

Keywords:

Inventory management; Multiple types of customers; Seasonal demand; Continuous demand; Newsvendor; (Q,r) model; Dynamic pricing; Critical level; Optimization; Simulation; Heuristics; Chinese healthcare supply chain; Global supply chain

Kim, Myung JinOptimization Approaches to Political Redistricting Problems
Doctor of Philosophy, The Ohio State University, 2011, Geography

Political redistricting problems are to divide a region into several districts with respect to several redistricting criteria so that political representatives are elected. These problems are difficult because the number of feasible redistricting plans is exponentially increased with the problem size. Also, several redistricting criteria must be satisfied at the same time, and it is difficult to formulate essential contiguity requirement in a mixed integer programming. A strict equal populated redistricting plan is intractable to solve.

The main purpose of this dissertation is to develop optimization approaches to political redistricting focusing on a strict equal population and contiguity and is to compare them with the existing researches. This dissertation develops two types of exact optimization models to political redistricting based on recent advances in solving land acquisition problems. The new exact models successfully formulate contiguity requirement and satisfy a strict equal population. They are compared with the existing exact model. Computational experiments show that the exact models face computational challenges for large data even though contiguity and a strict equal population are successfully formulated in a mixed integer program. Then, this dissertation moves to implement two different heuristic optimization models, which efficiently finds high-quality solutions. They are evaluated using existing data sets for comparisons. Throughout computational experiments, it is clearly known that all of the heuristics efficiently find near-optimal solutions, and among them the Give-And-Take greedy algorithm shows such efficiency even for the large size problems. Also, all of the heuristics show higher population equality than the existing plan of Iowa in 2000 and Give-And-Take greedy algorithm finds a plan with the highest population equality.

Committee:

Ningchuan Xiao (Advisor); Morton O'Kelly (Committee Member); Mei-Po Kwan (Committee Member)

Subjects:

Geographic Information Science; Geography

Keywords:

Political redistricting; Optimization

Blundell, ShelleyA Descriptive Phenomenological Investigation of the Academic Information Search Process Experience of Remedial Undergraduate Students
PHD, Kent State University, 2015, College of Communication and Information / School of Library and Information Science
This dissertation discusses the qualitative study which explored the academic information search process (AISP) experience of a group of undergraduate students enrolled in a remedial English course at a four-year, state university in Ohio, USA. The researcher used descriptive phenomenological methods to ascertain how participants explained and described their AISP experience, conducted to fulfill the requirements for the course-assigned research paper. Library and information science research bears out that an efficient AISP is connected to the possession of strong information literacy skills, and further, that strong information literacy skills are `intertwined’ with learning and academic progress in general. Because remedial undergraduate students are an academically at-risk population and have much lower graduation rates than their college-ready peers, this researcher wanted to create a research foundation for further investigation into this greatly understudied area in library and information science, toward finding practical ways to address remedial undergraduate students’ hampered academic progress through targeted, needs-based information literacy instruction. Primary findings from the study included the discovery of a pervasive sense of academic hopelessness in participants; the impact that seeking support services’ assistance had on participants’ AISP experience, particularly when their assistance failed participants; and the influence that `ecological’ factors (such as general perspectives on course instruction, feelings and emotions related to the study’s course, and previous college experiences) had on participants’ AISP experience. This study has implications for remedial educators and library and information science practitioners, and for targeted information literacy (IL) instruction. Specifically, this researcher recommends that collaborative IL instruction created through partnerships between remedial educators and academic librarians might be one way to help students overcome their sense of `academic hopelessness’ when conducting AISPs. Additionally, this researcher suggested that instructors consider using multi-modal learning objects within IL instruction and that remedial undergraduates be allowed to autonomously guide their own IL learning process. This researcher plans to engage in broader, quantitative study with similar student populations in the future to gain a deeper understanding of their information needs and behaviors, and ultimately create IL instruction which aids these students improve academically and persist toward graduation.

Committee:

Yin Zhang, Ph.D. (Committee Chair)

Subjects:

Curriculum Development; Education; Educational Evaluation; Educational Tests and Measurements; Higher Education; Information Science; Instructional Design; Library Science; Teacher Education; Teaching

Keywords:

Remedial undergraduate students, information literacy instruction, academic information-seeking, descriptive phenomenology

Wang, QifengEvaluating the Performance of the Freight Transportation System of the Great Lakes Region: An Intermodal Approach to Routing and Forecasting
Doctor of Philosophy, University of Toledo, 2014, Geography
Optimizing the supply chain has been increasingly important for the success of both manufacturers and retailers. This optimization has reduced costs for companies that are involved in the transport process and reduced cost to the end consumers, which brings benefits to both sides of the profit chain. Under difficult economic conditions, such as high fuel prices, mass congestion on major highway corridors, and strict reliability requirements for specific commodity types, the tangible as well as the intangible costs of freight transportation has been increasing rapidly. It swallows profits from the industry, increasing the cost for customers. Intermodal freight transportation has been introduced in recent years and has been more frequently selected by logistics companies, third-party logistics companies, and manufacturers to optimize the whole freight transport process. The trend of using more intermodal freight transportation is discussed in a qualitative perspective in the first part of this dissertation. Then the dissertation introduces a new shortest path algorithm entitled Tree Spanning Method (TSM) for large network processing. The new TSM algorithm is used as the main route planning algorithm throughout the dissertation for software development as well as freight demand forecasting. Due to the lack of specialized intermodal freight planning software in the industry, this dissertation discusses the key techniques in creating a specialized freight planning software, and a beta version of the software entitled "RouteInfo" is developed and introduced. The software works in a fashion similar to the Spatial Decision Support System. It enables users to be fully involved in the decision-making process and is able to determine the least expensive path between origins and designations on an integrated intermodal network. Real data includes USA highways and Canadian highways, and rail and maritime networks are integrated into the graphical user interface. Freight demand forecasting in the Great Lakes region is another focus of this dissertation. By using a four-step freight demand forecasting model at disaggregated (county) level, the travel patterns of freight transportation between 2010 and 2030 are obtained in the research area. The forecasting result is then used to quantitatively analyze the cost benefits of using more intermodal transportation options. Under the current situation of limited budgets, this dissertation proposes an intermodal solution that is able to solve the congestion issue without any highway expansion in the research area. The cost saving of this solution is also analyzed quantitatively. Overall, this dissertation is similar to a comprehensive consulting report. It proposes a new, shortest path algorithm which can be applied to the intermodal route planning. A new intermodal freight planning software is developed under a Python-based framework. The travel pattern of the freight transportation is estimated in the near future, and a solution is proposed to improve the transportation system in the research area in a cost-effective fashion.

Committee:

Peter Lindquist, Ph.D. (Committee Chair); Daniel Hammel, Ph.D. (Committee Member); Eddie Yein Juin Chou, P.E. (Committee Member); Neil Reid, Ph.D. (Committee Member); Yue Zhang, Ph.D. (Committee Member)

Subjects:

Geographic Information Science; Transportation; Transportation Planning

Keywords:

Intermodal Freight Transportation, Freight Demand Forecasting, Freight Flow Optimization, Shortest Path Route Planning, Geographic Information Systems

Shackelford, Philip ClaytonOn the Wings of the Wind: The United States Air Force Security Service and Its Impact on Signals Intelligence in the Cold War
BA, Kent State University, 2014, College of Arts and Sciences / Department of History
The United States Air Force Security Service (USAFSS), created in 1948, was the first signals intelligence organization to be created post-World War II and played an integral role in Cold War intelligence gathering. Indeed, despite its relatively young age compared to its Army and Navy counterparts, the USAFSS soon became the premier agency for signals intelligence in the early Cold War and was responsible for hundreds of secret listening posts around the world. This thesis argues that the USAFSS was able to have such a large impact on the post-World War II intelligence community due to a high level of technological proficiency, dedication, and a close working relationship with the National Security Agency (NSA) after its establishment in 1952. Using oral history interviews and declassified government documents, this thesis explores how the USAFSS was established and how it grew to leave a lasting impact for both contemporary Cold War intelligence agencies and the modern incarnation of Air Force intelligence.

Committee:

Elizabeth Smith-Pryor, Ph.D (Advisor); Timothy Scarnecchia, Ph.D (Committee Member); Fred Endres, Ph.D (Committee Member); Leslie Heaphy, Ph.D (Committee Member)

Subjects:

Armed Forces; Computer Science; Engineering; European History; History; Information Science; Information Technology; International Relations; Mass Communications; Military History; Military Studies; Modern History; Political Science; Russian History; Science History; Technical Communication; Technology; World History

Keywords:

Air Force; United States Air Force; Security Service; National Security; Intelligence; Signals Intelligence; Cold War; Soviet Union; United States; Armed Forces; National Security Agency; NSA; USAFSS; Cold War History; History; United States Military;

Huff, David AllanWater Quality of the Upper Little Miami River Watershed in Ohio: Impacts of Natural and Anthropogenic Processes.
Master of Science (MS), Wright State University, 2015, Earth and Environmental Sciences
Stream water quality is increasingly threatened by expanding anthropogenic activities, mainly through point source discharges and urban and agricultural runoffs of contaminants getting through a water body’s watershed resulting in pollution. Concerns developed as to whether urban or agricultural type activities were causing most water quality impairment issues in the upper Little Miami River watershed in southwest Ohio. Characterizing the upper Little Miami River (LMR) watershed with respect to water chemistry and Land Use/Land Cover (LULC) while evaluating the sources of any higher than expected natural parameter concentrations, with a strong emphasis on the nutrients phosphorus and nitrate, serves as this study’s purpose. Efforts are made to determine the greatest non-point source nutrient contribution by specific LULC type watersheds and compare findings with known point source nutrient contributions. Up to 23 sites were sampled during dry weather conditions covering all seasons except winter, ranging from July 2009 to November 2010. Sampling began near the head works of the upper LMR watershed at LMR mile 102, site #1 and ended with site #23 at LMR mile 51.3. Data obtained from the analysis of these samples has been comparatively graphed, spatially and statistically analyzed, and worked into loading calculations for comparisons to available online data, such as point source information. General water chemistry measurements show trends of specific ion concentrations, such as sodium and chloride, in relation to LULC drainage areas connected to sampled pour points. Nutrients such as phosphorus and nitrate have concentration amounts significantly influenced by non-agricultural anthropogenic activities. Statistical analyses of the generated data support the observed trends through correlation coefficients. Estimated stream/river flows at the sampled sites provide loading value development of specific parameters that further support significant trends and correlations even when at times the site concentration values of specific parameters drop downstream due to dilution by incoming natural waters. Observations of most significance involved the nutrient phosphorus and the salt NaCl, which showed the highest concentrations to be associated with urban type Land Uses/ Land Covers, such as residential, commercial, industrial, transportation, urban grasses, and drainage classes. Further study revealed that Water Reclamation Facilities (WRF) residing within the urban areas, provided the major source of phosphorus. Where WRF discharge loadings could be separated from estimated loadings calculated at the sample sites, though only in a small section of the whole study area, Agricultural as well as Urban Grasses LULC watershed types show to be at least a secondary source of the nutrients phosphorus and nitrate.

Committee:

Songlin Cheng, Ph.D. (Committee Chair); Abinash Agrawal, Ph.D. (Committee Member); Doyle Watts, Ph.D. (Committee Member)

Subjects:

Environmental Education; Environmental Science; Environmental Studies; Geochemistry; Geographic Information Science; Hydrologic Sciences

Keywords:

water quality; water chemistry; river; stream; pollution; LULC; Land Use Land Cover; nitrogen; nitrate; phosphorus; total phosphorus; Little Miami River; Ohio National Scenic River; upper Little Miami River watershed; watershed; delineated sub basins;

Rahman, MunshiEnvironmental and Social Vulnerabilities and Livelihoods of Fishing Communities of Kutubdia Island, Bangladesh
PHD, Kent State University, 2015, College of Arts and Sciences / Department of Geography
Bangladesh is one of the most vulnerable countries in terms of natural hazards due to its location and population density. Fishing communities of the coastal areas of Bangladesh are an especially vulnerable group of people due to natural disasters as well as socio-economic factors. Fishing communities of Kutubdia Island were considered in this study due to the risks driven by environmental change, natural hazards and disasters, and risks associated with fishing as an occupation. Death/disappearing of fishers at sea during fishing activities because of extreme weather events and lack of safety equipment are frequent in Bangladeshi coastal villages. Yet, no such study was available that estimated the number of fishers died or went missing at sea and the consequences of the victims’ families. The objective of this study is to examine the vulnerability associated with the livelihoods of fishing communities of Kutubdia Island, Bangladesh. A pilot study was conducted in May and June 2012, to develop questionnaire for surveys and became familiar with the environment, culture, and local people for conducting the surveys. From May to July 2013, questionnaire surveys were conducted by interviewing 300 households of fishing communities using national voter lists provided by the local government officials. Focus Group Discussion (FGD) was conducted with ordinary fishers and lessors separately. Land cover change detection and assessment of landuse patterns was considered in this study because most of the families involved in fishing are also involved in crop cultivation and salt farming in that region. Geographic Information System (GIS) and remote sensing techniques were used to detect land cover changes from 1972 to 2013, and the 2012 landuse patterns were estimated by using spatial video collected by contour Global Positioning System (GPS). Results of the surveys indicated the number of deaths/disappearing of fishers was 109. There were families that lost more than one household member and relative. Consequences to the families that lost fishers were dire as stated by the victims’ families. Some recommendations for reducing vulnerability of fishing communities are provided. Finally, a model is proposed to address the vulnerability and livelihoods of fishing communities of Kutubdia Island, Bangladesh. This study would be useful for taking initiatives for reducing vulnerability and address the livelihoods of fishing communities of Kutubdia Island. However, besides Bangladesh this study will be helpful to adopt policies and action plans for addressing vulnerability and livelihoods of coastal communities in other developing countries in the world (e.g., India, Sri Lanka, Indonesia, and Kenya) where similar vulnerability and livelihoods exist.

Committee:

Thomas Schmidlin, Ph.D. (Advisor); James Tyner, Ph.D. (Committee Member); Scott Sheridan, Ph.D. (Committee Member); Javed Khan, Ph.D. (Committee Member)

Subjects:

Environmental Studies; Geographic Information Science; Geography; Sustainability

Keywords:

Vulnerability, Livelihoods, Fishing Communities, Landuse landcover change, Kutubdia Island, Coastal Bangladesh

Clunis, Julaine SashanieDesigning an Ontology for Managing the Diets of Hypertensive Individuals
MLIS, Kent State University, 2016, College of Communication and Information / School of Library and Information Science
Making use of semantic technologies to combine various resources into one integrated environment, this study developed an ontology for hypertensive individuals to gain a better understanding of the nutrients in foods and recipes and what effect these have on the disease, prescribed drugs, and their general health. In particular, 10% of a sample of 500 recipes obtained from the web, and 10% of the food items from the USDA nutrient database was used as data in the ontology which had 75 classes, 22 object properties, and 33 data properties. The study established proto-personas to aid in development of competency questions which would be used with the Pellet reasoner to test whether the ontology could inform about nutrition goals for hypertensive individuals. The testing results provide evidence to support the idea that an ontology may be used to provide guidance to individuals with chronic disease, highlighting what foods may be safely consumed and which may cause problems. The conclusion is that an ontology can be successfully used to provide support to medical personnel and advance the cause of patient engagement as they seek to manage chronic illnesses such as hypertension.

Committee:

Marcia Zeng, Ph.D. (Advisor); Rebecca Meehan, Ph.D. (Advisor); Karen Gracy, Ph.D. (Committee Member)

Subjects:

Health; Information Science; Information Systems; Library Science; Web Studies

Keywords:

ontology; ontologies; semantic technologies; integrated environments; linked data; semantic web; hypertension; chronic disease management; knowledge organization systems; knowledge management; recipes; food;

Iannaggi, Corina MExploring Visitors’ Lived Experiences in Memorial Museums
MLIS, Kent State University, 2015, College of Communication and Information / School of Library and Information Science
There has been a surge of interest in what attracts visitors to memorial museums and other sites commemorative of historically significant tragic and violent events. Millions of people are drawn to these places each year, in turn creating a new area of research known as “dark tourism”. While much of the research has focused on the commodification and rise in popularity of dark tourism sites, there is little research from the visitor’s perspective inquiring about the meanings people take away from these sites, what they are experiencing, and what motivates them to visit. In light of this gap, an interpretative phenomenological analysis (IPA) study was conducted at the May 4th Visitors Center in Kent, Ohio. The May 4th Visitors Center commemorates the events leading up to and following the tragic shooting and deaths of several students by the National Guard in 1970. The intent of the study was to learn about visitors’ lived experiences at memorial museums and describe meanings made from these experiences; discover (if any) experiential themes are present across visitors; and determine if current descriptions of dark tourists match with visitors’ lived experiences in memorial museums from this study. After interviewing and analyzing four first-time visitors to the May 4th Visitors Center, four overarching themes were found amongst their experiences: 1. Connecting the past to the present: The person connects events memorialized in the museum to current events; 2. Putting oneself in the situation: The person makes a strong connection with those involved in the events memorialized, and realizes, “that could have been me”, or asks themselves, “what would I have done?”; 3. Justifying emotional reactions: Participants felt a need to explain why they reacted to the information on exhibit in a particular way; and 4. The power of multimodality: There is recognition of an enhanced experience due to the various ways information is presented in the exhibit (i.e. text, graphics, photographs, audio, video). The data suggests that these themes are the center of a multi-faceted experience uniquely felt by each participant and although everyone is different, ultimately it is suggested that the four themes derived from the participants’ experiences in this study can be seen as the foundation of the lived experience to memorial museums. While one cannot make the assumption that these same themes will apply to all visitors in all memorial museums, the results do shed light on how visitors relate to and make meaning of their visit, demonstrating that lived experience research has the potential to enhance our understanding of visitors to memorial museums and other commemorative sites.

Committee:

Kiersten F. Latham (Committee Chair)

Subjects:

Communication; Information Science; Museum Studies; Museums

Keywords:

Memorial museums; dark tourism; IPA; lived experience

Su, XiaoliVariations of Continental Ice Sheets Combining Satellite Gravimetry and Altimetry
Doctor of Philosophy, The Ohio State University, 2015, Geodetic Science and Surveying
Knowledge of mass variations of continental ice sheets including both Greenland ice sheet (GrIS) and Antarctic ice sheet (AIS) is important for quantifying their contribution to present-day sea level rise. Previous estimates for the respective trend of mass variations over both ice sheets using the Gravity Recovery and Climate Experiment (GRACE) data differ widely, primarily contaminated by large uncertainties of glacial isostatic adjustment (GIA) models over Antarctica, inter-annual or longer variations due to the relatively short data span, and also limited by the coarse spatial resolution (~333 km) of GRACE data. Satellite radar altimetry, i.e., the Environmental satellite (Envisat) altimetry, measures ice sheet elevation change with much better spatial resolution (~25 km) especially over polar regions but requires the density of ice/snow associated with measured elevation change to infer mass change. In this study, GRACE-derived mass variations and Envisat-observed elevation changes are investigated primarily at the inter-annual scale, with the focus on estimating nominal density of ice/snow associated with measured inter-annual mass and elevation changes. To process Envisat data, the along-track repeat analysis is modified separately, with surface gradient corrected by the use of digital elevation model (DEM) and collinear method. By comparing the root mean square (RMS), the trends of elevation changes generated from both methods, and the corresponding uncertainties of trends, the modified collinear method is demonstrated to be more effective for surface gradient correction. Moreover, elevation change retrieved by the ice-1 and ice-2 waveform retracking algorithms are compared in three cases over the AIS, with results confirming that for the ice-2 algorithm, empirical corrections from changes in backscatter and waveform shape parameters are needed. The trend of elevation change retrieved by the ice-1 algorithm with only backscatter analysis is consistent with that from the ice-2 algorithm with correction from changes in backscatter and waveform shape parameters. The two inter-annual anomalies of mass change from GRACE data and elevation change from Envisat data are respectively extracted over both ice sheets. Positive correlations are found over most of regions in both ice sheets; negative correlations appear in a small part of Northeast GrIS and parts of East AIS. Furthermore, assuming that both techniques can sense the same geophysical process, nominal densities are estimated separately over 9 regions in the GrIS and 14 regions in the AIS. Over the GrIS, the nominal densities range from 299.15±11.2 kg/m3 to 764.57±43.4 kg/m3 over 7 regions, and are physically unrealistic over the other 2 selected regions. For the AIS, the estimated nominal densities range from 317.49±24.2 kg/m3 to 479.81±25.3 kg/m3 over 4 regions (correlation coefficients >0.7); the nominal density is 450.17±28.8 kg/m3 during 2003–2006 and 812.45±44.3 kg/m3 during 2007–2009, and exhibits time dependence over the Amundsen Sea (AS) sector; for another 4 selected regions, the estimated densities are slightly smaller than snow density. For the other regions, the estimated densities are physically unrealistic. Compared with the results from a previous study, the area of negative correlations is now 21% over Antarctica, showing a significant reduction of 40%.

Committee:

C.K. Shum (Advisor); Christopher Jekeli (Committee Member); Ian Howat (Committee Member); Kenneth Jezek (Committee Member); Michael Bevis (Committee Member)

Subjects:

Climate Change; Geographic Information Science; Geophysics

Keywords:

continental ice sheets; satellite gravimetry; satellite altimetry

Lockshin, SamSpatial characterization of Western Interior Seaway paleoceanography using foraminifera, fuzzy sets and Dempster-Shafer theory
Master of Science (MS), Bowling Green State University, 2016, Geology
The spatial paleoceanography of the entire Western Interior Seaway (WIS) during the Cenomanian-Turonian Oceanic Anoxic Event has been reconstructed quantitatively for the first time using Geographic Information Systems. Models of foraminiferal occurrences—derived from Dempster-Shafer theory and driven by fuzzy sets of stratigraphic and spatial data—reflect water mass distributions during a brief period of rapid biotic turnover and oceanographic changes in a greenhouse world. Dempster-Shafer theory is a general framework for approximate reasoning based on combining information (evidence) to predict the probability (belief) that any phenomenon may occur. Because of the inherent imprecisions associated with paleontological data (e.g., preservational and sampling biases, missing time, reliance on expert knowledge), especially at fine-scale temporal resolutions, Dempster-Shafer theory is an appropriate technique because it factors uncertainty directly into its models. Locality data for four benthic and one planktic foraminiferal species and lithologic and geochemical data from sites distributed throughout the WIS were compiled from four ammonoid biozones of the Upper Cenomanian and Early Turonian stages. Of the 14 environmental parameters included in the dataset, percent silt, percent total carbonate, and depositional environment (essentially water depth) were associated with foraminiferal occurrences. The inductive Dempster-Shafer belief models for foraminiferal occurrences reveal the positions of northern and southern water masses consistent with the oceanographic gyre circulation pattern that dominated in the seaway during the Cenomanian- Turonian Boundary Event. The water-mixing interface in the southwestern part of the WIS was mostly restricted to the Four Corners region of the US, while the zone of overlap of northern and southern waters encompassed a much larger area along the eastern margin, where southern waters occasionally entered from the tropics. In addition to its paleospatial significance, this study introduces a rigorous, quantitative methodology with which to analyze paleontological occurrence data, assess the degree of uncertainty and prioritize regions for additional data collection.

Committee:

Margaret Yacobucci, Dr. (Advisor); Peter Gorsevski, Dr. (Committee Member); Andrew Gregory, Dr. (Committee Member)

Subjects:

Earth; Geographic Information Science; Geography; Geology; Marine Geology; Oceanography; Paleoecology; Paleontology; Statistics

Keywords:

paleontology; GIS; foraminifera; species distribution modeling; fuzzy sets; Dempster-Shafer theory; paleoceanography; Western Interior Seaway; Cenomanian; Turonian; spatial modeling; Bayesian statistics; Oceanic Anoxic Event; uncertainty modeling; ArcGIS

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