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A Data Driven Approach To Quantify The Impact Of Crashes, Obaidur Rahman Kazi
A Data Driven Approach To Quantify The Impact Of Crashes, Obaidur Rahman Kazi
Theses and Dissertations--Civil Engineering
The growth of data has begun to transform the transportation research and policy, and open a new window for analyzing the impact of crashes. Currently for the crash impact analysis, researchers tend to rely on reported incident duration, which may not always be accurate. Further, impact of the crashes could linger a much longer time at upstream, even if the records are correct for the crash spot and it is a challenge to quantify the impact of a crash from the complex dynamics of the recurrent and non-recurrent congested condition. Therefore, a difference-in-speed approach is developed in this research to …
Topics On Register Synthesis Problems, Weihua Liu
Topics On Register Synthesis Problems, Weihua Liu
Theses and Dissertations--Computer Science
Pseudo-random sequences are ubiquitous in modern electronics and information technology. High speed generators of such sequences play essential roles in various engineering applications, such as stream ciphers, radar systems, multiple access systems, and quasi-Monte-Carlo simulation. Given a short prefix of a sequence, it is undesirable to have an efficient algorithm that can synthesize a generator which can predict the whole sequence. Otherwise, a cryptanalytic attack can be launched against the system based on that given sequence.
Linear feedback shift registers (LFSRs) are the most widely studied pseudorandom sequence generators. The LFSR synthesis problem can be solved by the Berlekamp-Massey algorithm, …
Secure And Authenticated Message Dissemination In Vehicular Ad Hoc Networks And An Incentive-Based Architecture For Vehicular Cloud, Kiho Lim
Theses and Dissertations--Computer Science
Vehicular ad hoc Networks (VANETs) allow vehicles to form a self-organized network. VANETs are likely to be widely deployed in the future, given the interest shown by industry in self-driving cars and satisfying their customers various interests. Problems related to Mobile ad hoc Networks (MANETs) such as routing, security, etc.have been extensively studied. Even though VANETs are special type of MANETs, solutions proposed for MANETs cannot be directly applied to VANETs because all problems related to MANETs have been studied for small networks. Moreover, in MANETs, nodes can move randomly. On the other hand, movement of nodes in VANETs are …
Biomedical Word Sense Disambiguation With Neural Word And Concept Embeddings, Akm Sabbir
Biomedical Word Sense Disambiguation With Neural Word And Concept Embeddings, Akm Sabbir
Theses and Dissertations--Computer Science
Addressing ambiguity issues is an important step in natural language processing (NLP) pipelines designed for information extraction and knowledge discovery. This problem is also common in biomedicine where NLP applications have become indispensable to exploit latent information from biomedical literature and clinical narratives from electronic medical records. In this thesis, we propose an ensemble model that employs recent advances in neural word embeddings along with knowledge based approaches to build a biomedical word sense disambiguation (WSD) system. Specifically, our system identities the correct sense from a given set of candidates for each ambiguous word when presented in its context (surrounding …
Dating Deformation In The Palmer Zone Of Transpression, Central Massachusetts: Temporal Constraints On Models For Progressive Deformation In The Middle Crust, James K. Mcculla
Dating Deformation In The Palmer Zone Of Transpression, Central Massachusetts: Temporal Constraints On Models For Progressive Deformation In The Middle Crust, James K. Mcculla
Theses and Dissertations--Earth and Environmental Sciences
The Palmer Zone of Transpression (PZoT) in the Bronson Hill zone of central Massachusetts is an expression of late Paleozoic oblique convergence between Avalonia and Laurentia. The steeply W-dipping, N-S trending PZoT is defined by bounding high strain zones (Mt. Dumplin on west, Central Maine and Conant Brook on east) of opposing shear sense enclosing the Monson orthogneiss. Research was designed to establish the timing of deformation to test the hypothesis that strain in transpressional systems occurs contemporaneously. An understanding of the timing of deformation in this zone could elucidate the mechanisms that formed the zone and contribute to a …
Lithostratigraphic And Geochemical Characterization Of The Upper Pennsylvanian ‘Wolfcamp D’ Shale, Midland Basin (Usa): Implications For Paleoenvironments And Unconventional Petroleum Reserviors, Patrick W. Baldwin
Theses and Dissertations--Earth and Environmental Sciences
An integrated stratigraphic analysis of a ~350 ft drill core from Upton County (Texas) has revealed pervasive variability of several key siliciclastic and carbonate lithofacies in vertical section, where organic-rich siliceous mudrock beds alternate with aluminum-rich mudrocks and calcareous gravity flow deposits. Sediment chemistry, especially major and trace elements derived from x-ray fluorescence, captures this variability with high sensitivity. The high frequency chemostratigraphic variability appears to be cyclic, and it is interpreted to represent the first example of deep-water Late Pennsylvanian cyclothems for the Midland Basin. Positive trace metal (Mo, Cr) correlations to total organic carbon and gamma ray response …
Role Of Hairy-Related (Her) Genes During Vertebrate Retinal Development And Regeneration, Stephen G. Wilson
Role Of Hairy-Related (Her) Genes During Vertebrate Retinal Development And Regeneration, Stephen G. Wilson
Theses and Dissertations--Biology
Development and regeneration of the vertebrate eye are the result of complex interactions of regulatory networks and spatiotemporally controlled gene expression events. During embryonic retinal development, the coordination of cell signaling and transcriptional regulation allows for a relatively homogenous sheet of neuroepithelial cells to proliferate and differentiate in-to a multilayered, light sensitive retinal tissue. Following injury, the retinas of many cold-blooded vertebrates, such as the zebrafish, undergo a proliferative response that results not only in new retinal cells of the correct type in the correct location, but also functional integration of these cells and restoration of vision. In order for …
Integrated Geophysical Methods In Investigation Of Claiborne Aquifer Hydrostratigraphy, Jackson Purchase, Kentucky, Marie Cooper
Integrated Geophysical Methods In Investigation Of Claiborne Aquifer Hydrostratigraphy, Jackson Purchase, Kentucky, Marie Cooper
Theses and Dissertations--Earth and Environmental Sciences
Increased groundwater withdrawals associated with agricultural irrigation in the Jackson Purchase have prompted questions related to groundwater availability and sustainability. Key factors in addressing these questions are understanding the extent and variation in thickness of the local hydrostratigraphic system, which is the upper part of the Mississippi Embayment aquifer system. Correlations of 70 gamma-ray well logs, and 49 resistivity logs were made across parts of the Jackson Purchase in Fulton and Hickman Counties in order to delineate the upper Claiborne aquifer and middle Claiborne confining unit. Commercial software (i.e. Petra 3.8.3) was used to generate cross sections, structure and isopach …
Mobility Of Escherichia Coli Within Karst Terrains, Kentucky, Usa, Ashley M. Bandy
Mobility Of Escherichia Coli Within Karst Terrains, Kentucky, Usa, Ashley M. Bandy
Theses and Dissertations--Earth and Environmental Sciences
Bacterial contamination of karst aquifers is a concern as water quality across the globe deteriorates in the face of decreasing water security. This study examined the transport and attenuation of two non-virulent isolates of Escherichia coli in relation to traditional groundwater tracers such as rhodamine WT dye and latex microspheres in two karst regions in Kentucky. Differential movement between the four tracers was observed in both epikarst and karst aquifer traces, with differences in behavior dependent on flow conditions. Attenuation was greater for the bacterial isolate containing the iha gene, compared to the isolate containing the kps gene. Microspheres of …
Spring Responses To Storms And Seasonal Variations In Recharge In The Middle Atlas Region Of Morocco, Brett Andrew Howell
Spring Responses To Storms And Seasonal Variations In Recharge In The Middle Atlas Region Of Morocco, Brett Andrew Howell
Theses and Dissertations--Earth and Environmental Sciences
Springs in the Middle Atlas Mountains of Morocco are significant sources for public water supply. From March 2014 to May 2015, water temperatures were measured hourly at three springs (Ribaa, Sidi Rached, and Zerouka); water levels were measured hourly at Sidi Rached and Zerouka; and daily turbidity data were obtained from Ribaa. From March 2014 to March 2015, daily water samples were taken at Zerouka for analyses of the stable isotopes deuterium and oxygen-18. Hourly weather data (precipitation and air temperature) were available from March 2014 to May 2015 from Ifrane, near Zerouka. Temperature responses varied between the springs, showing …
Paleoearthquakes Of The Past ~6000 Years At The Dead Mouse Site, West-Central Denali Fault At The Nenana River, Alaska, Joseph K. Carlson
Paleoearthquakes Of The Past ~6000 Years At The Dead Mouse Site, West-Central Denali Fault At The Nenana River, Alaska, Joseph K. Carlson
Theses and Dissertations--Earth and Environmental Sciences
The Denali fault (DF) in south-central Alaska is a major right lateral strike-slip fault that parallels the Alaska Range for much of its length. This fault represents the largest seismogenic source for interior Alaska but due to its remote location and difficulty of access, a dearth of paleoearthquake (PEQ) information exists for this important feature. The fault system is over 1200 km in length and identification of paleoseismic sites that preserve more that 2-3 PEQs has proven challenging. In 2012 and 2015, we developed the ‘Dead Mouse’ site, which provides the first long PEQ record west of the 2002 rupture …
Denali In A Box: Analog Experiments Modeled After A Natural Setting Provide Insight On Gentle Restraining Bend Deformation, Anne M. Fendick
Denali In A Box: Analog Experiments Modeled After A Natural Setting Provide Insight On Gentle Restraining Bend Deformation, Anne M. Fendick
Theses and Dissertations--Earth and Environmental Sciences
The Mount McKinley restraining bend (MMRB) creates an ~18° left-step in the arcuate surface trace of the dextral Denali Fault in south-central Alaska. Despite being a large, crustal-scale fault, little is understood about the controls on deformation within the MMRB. Similarities between previous wet kaolin analog modeling and the MMRB suggest that the first-order deformation patterns may derive from similar mechanisms. We compare uplift patterns, localization of deformation, formation of new faults, and displacement fields from the analog model and the natural setting to assess the influence of different variables on the overall system. Despite strong rheological heterogeneity in the …
Development Of A Semi-Automated Methodology For Discriminating Between Natural And Manmade Seismic Events Using The Oiink Seismic Array, Paul Rodriguez Asihama
Development Of A Semi-Automated Methodology For Discriminating Between Natural And Manmade Seismic Events Using The Oiink Seismic Array, Paul Rodriguez Asihama
Theses and Dissertations--Earth and Environmental Sciences
Broadband waveforms from the Ozark, Indiana, Illinois, Kentucky temporary seismic array OIINK, a Flexible Array in the EarthScope project, were used to develop routines to identify and remove mine blast events from a database of local events and preserve the infrequent, small, natural earthquakes. The approach taken was to first create a database of all seismic events that were detected by the OIINK Seismic Array. False-detections, events detected from outside of the project area (approx. 302 thousand square km), and known (i.e. cataloged) local earthquake were also removed. The remaining in the database were local unknown events. During the Phase …
Stratigraphic, Geochemical, And Well Log Analysis Of The Wolfcamp-D Unconventional Play In The Central Midland Basin, Texas, Patrick Thomas Ryan
Stratigraphic, Geochemical, And Well Log Analysis Of The Wolfcamp-D Unconventional Play In The Central Midland Basin, Texas, Patrick Thomas Ryan
Theses and Dissertations--Earth and Environmental Sciences
This M.S. thesis utilizes diverse subsurface datasets from the central Midland Basin, a recently reinvigorated petroleum producing region, to better understand the depositional history of the prospective Wolfcamp-D interval. An integrated set of methods were applied to ~320 ft of drill core from Midland County (Texas). Elemental chemostratigraphy collected via x-ray fluorescence highlights the pervasive fine-scale variability in the stratigraphy of the core, and aided in the classification of three different mudrock facies types. Organic-rich, siliceous mudrocks are cyclically interbedded with aluminum-rich mudrocks and carbonates throughout the Wolfcamp-D. Trace metal correlations with total organic carbon indicate slow bottom-water recharge from …
Field, Geochronologic, And Geochemical Constraints On Late Precambrian To Early Paleozoic Terrane Accretion In The Southern Appalachian Blue Ridge Province, Emma A. Larkin
Theses and Dissertations--Earth and Environmental Sciences
Xenolith-bearing orthogneiss of Amazonian affinity discovered in the Dellwood quadrangle in the Blue Ridge basement complex represents the oldest crustal component of the southern Appalachians (1.33 – 1.37 Ga: Quinn, 2012). New U-Pb zircon ages for migmatitic paragneiss of the Cartoogechaye terrane exposed in the Dellwood quadrangle reveal two unique detrital zircon age signatures that indicate either a local eastern Laurentian margin source or an exotic source. Detailed mapping, whole rock geochemistry, and U-Pb zircon geochronology were conducted to determine whether this exotic crustal component extends farther south into the Hazelwood 7.5” quadrangle. Lithological similarities exist between paragneisses in the …
Solutions To The LP Mixed Boundary Value Problem In C1,1 Domains, Laura D. Croyle
Solutions To The LP Mixed Boundary Value Problem In C1,1 Domains, Laura D. Croyle
Theses and Dissertations--Mathematics
We look at the mixed boundary value problem for elliptic operators in a bounded C1,1(ℝn) domain. The boundary is decomposed into disjoint parts, D and N, with Dirichlet and Neumann data, respectively. Expanding on work done by Ott and Brown, we find a larger range of values of p, 1 < p < n/(n-1), for which the Lp mixed problem has a unique solution with the non-tangential maximal function of the gradient in Lp(∂Ω).
In Search Of A Class Of Representatives For Su-Cobordism Using The Witten Genus, John E. Mosley
In Search Of A Class Of Representatives For Su-Cobordism Using The Witten Genus, John E. Mosley
Theses and Dissertations--Mathematics
In algebraic topology, we work to classify objects. My research aims to build a better understanding of one important notion of classification of differentiable manifolds called cobordism. Cobordism is an equivalence relation, and the equivalence classes in cobordism form a graded ring, with operations disjoint union and Cartesian product. My dissertation studies this graded ring in two ways:
1. by attempting to find preferred class representatives for each class in the ring.
2. by computing the image of the ring under an interesting ring homomorphism called the Witten Genus.
New Perspectives Of Quantum Analogues, Yue Cai
New Perspectives Of Quantum Analogues, Yue Cai
Theses and Dissertations--Mathematics
In this dissertation we discuss three problems. We first show the classical q-Stirling numbers of the second kind can be expressed more compactly as a pair of statistics on a subset of restricted growth words. We extend this enumerative result via a decomposition of a new poset which we call the Stirling poset of the second kind. The Stirling poset of the second kind supports an algebraic complex and a basis for integer homology is determined. A parallel enumerative, poset theoretic and homological study for the q-Stirling numbers of the first kind is done. We also give a bijective …
On Skew-Constacyclic Codes, Neville Lyons Fogarty
On Skew-Constacyclic Codes, Neville Lyons Fogarty
Theses and Dissertations--Mathematics
Cyclic codes are a well-known class of linear block codes with efficient decoding algorithms. In recent years they have been generalized to skew-constacyclic codes; such a generalization has previously been shown to be useful. We begin with a study of skew-polynomial rings so that we may examine these codes algebraically as quotient modules of non-commutative skew-polynomial rings. We introduce a skew-generalized circulant matrix to aid in examining skew-constacyclic codes, and we use it to recover a well-known result on the duals of skew-constacyclic codes from Boucher/Ulmer in 2011. We also motivate and develop a notion of idempotent elements in these …
Flag F-Vectors Of Polytopes With Few Vertices, Sarah A. Nelson
Flag F-Vectors Of Polytopes With Few Vertices, Sarah A. Nelson
Theses and Dissertations--Mathematics
We may describe a polytope P as the convex hull of n points in space. Here we consider the numbers of chains of faces of P. The toric g-vector and CD-index of P are useful invariants for encoding this information. For a simplicial polytope P, Lee defined the winding number wk in a Gale diagram corresponding to P. He showed that wk in the Gale diagram equals gk of the corresponding polytope. In this dissertation, we fully establish how to compute the g-vector for any polytope with few vertices from its …
Kronecker's Theory Of Binary Bilinear Forms With Applications To Representations Of Integers As Sums Of Three Squares, Jonathan A. Constable
Kronecker's Theory Of Binary Bilinear Forms With Applications To Representations Of Integers As Sums Of Three Squares, Jonathan A. Constable
Theses and Dissertations--Mathematics
In 1883 Leopold Kronecker published a paper containing “a few explanatory remarks” to an earlier paper of his from 1866. His work loosely connected the theory of integral binary bilinear forms to the theory of integral binary quadratic forms. In this dissertation we discover the statements within Kronecker's paper and offer detailed arithmetic proofs. We begin by developing the theory of binary bilinear forms and their automorphs, providing a classification of integral binary bilinear forms up to equivalence, proper equivalence and complete equivalence.
In the second chapter we introduce the class number, proper class number and complete class number as …
Imagination Bound: A Theoretical Imperative, Robert Michael Guerin
Imagination Bound: A Theoretical Imperative, Robert Michael Guerin
Theses and Dissertations--Philosophy
Kant’s theory of productive imagination falls at the center of the critical project. This is evident in the 1781 Critique of Pure Reason, where Kant claims that the productive imagination is a “fundamental faculty of the human soul” and indispensable for the construction of experience. And yet, in the second edition of 1787 Kant seemingly demotes this imagination as a mere “effect of the understanding on sensibility” and all but withdraws its place from the Transcendental Deduction.
In his 1929 Kant and the Problem of Metaphysics, Martin Heidegger provided an explanation for the revisions between 1781 and 1787. …
The Normative Architecture Of Reality: Towards An Object-Oriented Ethics, Justin L. Harmon
The Normative Architecture Of Reality: Towards An Object-Oriented Ethics, Justin L. Harmon
Theses and Dissertations--Philosophy
The fact-value distinction has structured and still structures ongoing debates in metaethics, and all of the major positions in the field (expressivism, cognitivist realism, and moral error theory) subscribe to it. In contrast, I claim that the fact-value distinction is a contingent product of our intellectual history and a prime object for questioning. The most forceful reason for rejecting the distinction is that it presupposes a problematic understanding of the subject-object divide whereby one tends to view humans as the sole source of normativity in the world. My dissertation aims to disclose the background against which human ethical praxis is …
Becoming What We Are: Virtue And Practical Wisdom As Natural Ends, Keith Buhler
Becoming What We Are: Virtue And Practical Wisdom As Natural Ends, Keith Buhler
Theses and Dissertations--Philosophy
This dissertation is about ethical naturalism. Philippa Foot and John McDowell both defend contemporary neo-Aristotelian ethics but each represents a rival expression of the same. They are united in the affirmation that virtue is ‘natural goodness’ for human beings. Nevertheless, they are divided in their rival conceptions of ‘nature.’ McDowell distinguishes second nature or the "space of reasons" from first nature or the “realm of law.” Foot rejects this division.
On Foot's naturalism, natural goodness is just as much a feature of first nature as health is, even though human practical reasoning is unique in the biological world. I defend …
Expectancy-Value In The Enrollment Factor Of Agricultural Education Youth, Morgan Schafbuch
Expectancy-Value In The Enrollment Factor Of Agricultural Education Youth, Morgan Schafbuch
Theses and Dissertations--Community & Leadership Development
This quantitative study considers the motivating factors for enrollment in secondary agricultural education courses from students whose home background is not from a farm. This study utilizes expectancy-value theory, and looks at students (n=211) from different agricultural backgrounds and the impact on their ability beliefs, expectancies for success, and usefulness, importance, and interest for enrollment in agricultural education courses. The results indicate that students who have no affiliation to a farm have the highest ability beliefs and expectancies for success towards agricultural education in relation to students who are from traditional agricultural backgrounds.
Heat And Mass Transfer In Baled Switchgrass For Storage And Bioconversion Applications, Drew F. Schiavone
Heat And Mass Transfer In Baled Switchgrass For Storage And Bioconversion Applications, Drew F. Schiavone
Theses and Dissertations--Biosystems and Agricultural Engineering
The temperature and moisture content of biomass feedstocks both play a critical role in minimizing storage and transportation costs, achieving effective bioconversion, and developing relevant postharvest quality models. Hence, this study characterizes the heat and mass transfer occurring within baled switchgrass through the development of a mathematical model describing the relevant thermal and physical properties of this specific substrate. This mathematical model accounts for the effect of internal heat generation and temperature-induced free convection within the material in order to improve prediction accuracy. Inclusion of these terms is considered novel in terms of similar biomass models.
Two disparate length scales, …
Development In Normal Mixture And Mixture Of Experts Modeling, Meng Qi
Development In Normal Mixture And Mixture Of Experts Modeling, Meng Qi
Theses and Dissertations--Statistics
In this dissertation, first we consider the problem of testing homogeneity and order in a contaminated normal model, when the data is correlated under some known covariance structure. To address this problem, we developed a moment based homogeneity and order test, and design weights for test statistics to increase power for homogeneity test. We applied our test to microarray about Down’s syndrome. This dissertation also studies a singular Bayesian information criterion (sBIC) for a bivariate hierarchical mixture model with varying weights, and develops a new data dependent information criterion (sFLIC).We apply our model and criteria to birth- weight and gestational …
Multi-State Models With Missing Covariates, Wenjie Lou
Multi-State Models With Missing Covariates, Wenjie Lou
Theses and Dissertations--Statistics
Multi-state models have been widely used to analyze longitudinal event history data obtained in medical studies. The tools and methods developed recently in this area require the complete observed datasets. While, in many applications measurements on certain components of the covariate vector are missing on some study subjects. In this dissertation, several likelihood-based methodologies were proposed to deal with datasets with different types of missing covariates efficiently when applying multi-state models.
Firstly, a maximum observed data likelihood method was proposed when the data has a univariate missing pattern and the missing covariate is a categorical variable. The construction of the …
Statistical Methods For Handling Intentional Inaccurate Responders, Kristen J. Mcquerry
Statistical Methods For Handling Intentional Inaccurate Responders, Kristen J. Mcquerry
Theses and Dissertations--Statistics
In self-report data, participants who provide incorrect responses are known as intentional inaccurate responders. This dissertation provides statistical analyses for address intentional inaccurate responses in the data.
Previous work with adolescent self-report, labeled survey participants who intentionally provide inaccurate answers as mischievous responders. This phenomenon also occurs in clinical research. For example, pregnant women who smoke may report that they are nonsmokers. Our advantage is that we do not solely have self-report answers and can verify responses with lab values. Currently, there is no clear method for handling these intentional inaccurate respondents when it comes to making statistical inferences.
We …
Topics In Logistic Regression Analysis, Zhiheng Xie
Topics In Logistic Regression Analysis, Zhiheng Xie
Theses and Dissertations--Statistics
Discrete-time Markov chains have been used to analyze the transition of subjects from intact cognition to dementia with mild cognitive impairment and global impairment as intervening transient states, and death as competing risk. A multinomial logistic regression model is used to estimate the probability distribution in each row of the one-step transition matrix that correspond to the transient states. We investigate some goodness of fit tests for a multinomial distribution with covariates to assess the fit of this model to the data. We propose a modified chi-square test statistic and a score test statistic for the multinomial assumption in each …