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Full-Text Articles in Physical Sciences and Mathematics

A Bayesian Programming Approach To Car-Following Model Calibration And Validation Using Limited Data, Franklin Abodo Jun 2022

A Bayesian Programming Approach To Car-Following Model Calibration And Validation Using Limited Data, Franklin Abodo

FIU Electronic Theses and Dissertations

Traffic simulation software is used by transportation researchers and engineers to design and evaluate changes to roadway networks. Underlying these simulators are mathematical models of microscopic driver behavior from which macroscopic measures of flow and congestion can be recovered. Many models are intended to apply to only a subset of possible traffic scenarios and roadway configurations, while others do not have any explicit constraint on their applicability. Work zones on highways are one scenario for which no model invented to date has been shown to accurately reproduce realistic driving behavior. This makes it difficult to optimize for safety and other …


Do Home Invasion Serial Killers Warrant A Distinct Classification From Other Serial Killer Location Types? A Retrospective Comparative Examination, Caroline V. Comerford Mar 2022

Do Home Invasion Serial Killers Warrant A Distinct Classification From Other Serial Killer Location Types? A Retrospective Comparative Examination, Caroline V. Comerford

FIU Electronic Theses and Dissertations

This dissertation seeks to address the research gap in serial homicide regarding home invasion serial killers (HISKs) and add to existing policy by providing insight and approaches to assist in serial murder investigations of such killers. Data for the study was obtained from the 2019 Radford University/Florida Gulf Coast University Serial Killer Database (RU/FGCU SKD) and additional public information searches. A retrospective comparative design and proportionate stratified random sampling of 326 serial killers from the RU/FGCU SKD (2019) were used to examine the differences and classifications of HISKs and non-home invasion serial killers (non-HISKs) in three investigations: (1) common characteristics; …


Examining The Effects Of Individual And Neighborhood Factors On Hiv Transmission Risk Potential Among People With Hiv, Semiu Olatunde Gbadamosi Mar 2022

Examining The Effects Of Individual And Neighborhood Factors On Hiv Transmission Risk Potential Among People With Hiv, Semiu Olatunde Gbadamosi

FIU Electronic Theses and Dissertations

HIV transmission risk significantly increases in late-diagnosed HIV and at HIV viral load (VL) >1500 copies/mL. The objective of this dissertation was to examine factors associated with HIV transmission risk potential for persons with HIV (PWH) using measures of time from HIV infection to diagnosis and trajectories of VL suppression. Additionally, we sought to determine whether a single yearly VL measure—the current standard to track the HIV epidemic in the United States—is reliable in assessing viral suppression for PWH. The first study estimated the distribution of time from HIV infection to diagnosis in Florida using a CD4 depletion model and …


A Machine Learning Framework For Identifying Molecular Biomarkers From Transcriptomic Cancer Data, Md Abdullah Al Mamun Mar 2022

A Machine Learning Framework For Identifying Molecular Biomarkers From Transcriptomic Cancer Data, Md Abdullah Al Mamun

FIU Electronic Theses and Dissertations

Cancer is a complex molecular process due to abnormal changes in the genome, such as mutation and copy number variation, and epigenetic aberrations such as dysregulations of long non-coding RNA (lncRNA). These abnormal changes are reflected in transcriptome by turning oncogenes on and tumor suppressor genes off, which are considered cancer biomarkers.

However, transcriptomic data is high dimensional, and finding the best subset of genes (features) related to causing cancer is computationally challenging and expensive. Thus, developing a feature selection framework to discover molecular biomarkers for cancer is critical.

Traditional approaches for biomarker discovery calculate the fold change for each …


Volitional Control Of Lower-Limb Prosthesis With Vision-Assisted Environmental Awareness, S M Shafiul Hasan Mar 2022

Volitional Control Of Lower-Limb Prosthesis With Vision-Assisted Environmental Awareness, S M Shafiul Hasan

FIU Electronic Theses and Dissertations

Early and reliable prediction of user’s intention to change locomotion mode or speed is critical for a smooth and natural lower limb prosthesis. Meanwhile, incorporation of explicit environmental feedback can facilitate context aware intelligent prosthesis which allows seamless operation in a variety of gait demands. This dissertation introduces environmental awareness through computer vision and enables early and accurate prediction of intention to start, stop or change speeds while walking. Electromyography (EMG), Electroencephalography (EEG), Inertial Measurement Unit (IMU), and Ground Reaction Force (GRF) sensors were used to predict intention to start, stop or increase walking speed. Furthermore, it was investigated whether …


Integrating Compound Flood Conditions Through 2d Hydraulic Modeling For Simulating Flood Risk Processes In Coastal Cities, Francisco Pena Guerra Mr. Oct 2021

Integrating Compound Flood Conditions Through 2d Hydraulic Modeling For Simulating Flood Risk Processes In Coastal Cities, Francisco Pena Guerra Mr.

FIU Electronic Theses and Dissertations

Low elevation coastal karst environments are highly vulnerable to flooding conditions due to climate change. Trends in rising global temperatures have increased the frequency and intensity of extreme precipitation, hydrometeorological phenomena and sea level rise, exacerbating the impact of pluvial, fluvial, coastal and groundwater flood hazards. Compound flooding events amplify flood hazards and pose a higher threat to residents and infrastructure in unison compared to independent phenomena. Recent advancements in coupling hydrologic and hydraulic modeling frameworks have improved our ability to account for the combined effects of extreme pluvial, fluvial, and coastal flood hazards. This innovation in the hydroinformatics field …


A Review Of Logistic Regression And Its Application, Sultana Mubarika Rahman Chowdhury Jun 2021

A Review Of Logistic Regression And Its Application, Sultana Mubarika Rahman Chowdhury

FIU Electronic Theses and Dissertations

The purpose of this thesis is to do an in-depth review of logistic regression and its application. Additionally, comparison of four different methods of coefficient standardization was done using Heart Disease Dataset. These methods were compared based on testing accuracy, training accuracy, area under the curve, sensitivity, and specificity. Furthermore, logistic regression analysis was applied to National Longitudinal Study of Adolescence Health Survey (Add health) dataset to examine the relationship between anxiety or panic disorder and history of childhood maltreatment, medical conditions such as ADHD, PTSD, some socio-economic conditions and addiction. Results indicated; history of abuse has a significant effect …


Exercise, Cognition, And Cannabis Use In Adolescents, Ileana Pacheco-Colón May 2021

Exercise, Cognition, And Cannabis Use In Adolescents, Ileana Pacheco-Colón

FIU Electronic Theses and Dissertations

Heavy and/or chronic cannabis use has been associated with neurocognitive impairment and decline, often in domains such as memory and executive functioning. On the other hand, exercise has been linked to positive effects on brain and cognitive health across the lifespan, as well as to better substance use outcomes. Despite this, little is known about the ways in which exercise could help prevent or ameliorate adverse cannabis-related outcomes among adolescents.

Through three separate studies, the current dissertation examines interrelations among exercise, cognition, and cannabis use in children and adolescents in an effort to determine whether exercise can prevent or ameliorate …


Evaluation Of Parametric And Nonparametric Statistical Models In Wrong-Way Driving Crash Severity Prediction, Sajidur Rahman Nafis Mar 2021

Evaluation Of Parametric And Nonparametric Statistical Models In Wrong-Way Driving Crash Severity Prediction, Sajidur Rahman Nafis

FIU Electronic Theses and Dissertations

Wrong-way driving (WWD) crashes result in more fatalities per crash, involve more vehicles, and cause extended road closures compared to other types of crashes. Although crashes involving wrong-way drivers are relatively few, they often lead to fatalities and serious injuries. Researchers have been using parametric statistical models to identify factors that affect WWD crash severity. However, these parametric models are generally based on several assumptions, and the results could generate numerous errors and become questionable when these assumptions are violated. On the other hand, nonparametric methods such as data mining or machine learning techniques do not use a predetermined functional …


Statistical Modeling Of Private Sector Participation In Disaster Risk Reduction Data, Wupeng Yin Nov 2020

Statistical Modeling Of Private Sector Participation In Disaster Risk Reduction Data, Wupeng Yin

FIU Electronic Theses and Dissertations

The impacts of disaster on the private sector are inevitable, but their risks can be managed and reduced by preventively evaluative measures. Disaster risk reduction index (DRRI) and Disaster Experience (DE) variables were investigated in a survey study in six Western Hemisphere cities within the private sector of various business sizes. Our thesis built and evaluated 16 predictive models of DRRI with 36 categorical predictors and N = 1162 observations. Four statistical methods for linear regression and five for classification as well as seven machine learning methods were utilized. We also used stepwise selection and regulation methods for variable selection. …


Development Of A Dna Methylation Multiplex Assay For Body Fluid Identification And Age Determination, Quentin Gauthier Nov 2020

Development Of A Dna Methylation Multiplex Assay For Body Fluid Identification And Age Determination, Quentin Gauthier

FIU Electronic Theses and Dissertations

For forensic laboratories, the determination of body fluid origin of samples collected at a crime scene are typically presumptive and often destructive. However, given that in certain cases the presence of DNA is not in dispute and rather where the DNA came from is of primary concern, new methodologies are needed. Epigenetic modifications, such as DNA methylation, affect gene expression in every cell of every mammal. These DNA methylation patterns typically are observed as the addition of a methyl group on the 5’ carbon of a cytosine followed by guanine (CpG). Methylation patterns have been observed to change in response …


Development Of Gaussian Learning Algorithms For Early Detection Of Alzheimer's Disease, Chen Fang Mar 2020

Development Of Gaussian Learning Algorithms For Early Detection Of Alzheimer's Disease, Chen Fang

FIU Electronic Theses and Dissertations

Alzheimer’s disease (AD) is the most common form of dementia affecting 10% of the population over the age of 65 and the growing costs in managing AD are estimated to be $259 billion, according to data reported in the 2017 by the Alzheimer's Association. Moreover, with cognitive decline, daily life of the affected persons and their families are severely impacted. Taking advantage of the diagnosis of AD and its prodromal stage of mild cognitive impairment (MCI), an early treatment may help patients preserve the quality of life and slow the progression of the disease, even though the underlying disease cannot …


Best Probable Subset: A New Method For Reducing Data Dimensionality In Linear Regression, Elieser Nodarse Apr 2019

Best Probable Subset: A New Method For Reducing Data Dimensionality In Linear Regression, Elieser Nodarse

FIU Electronic Theses and Dissertations

Regression is a statistical technique for modeling the relationship between a dependent variable Y and two or more predictor variables, also known as regressors. In the broad field of regression, there exists a special case in which the relationship between the dependent variable and the regressor(s) is linear. This is known as linear regression.

The purpose of this paper is to create a useful method that effectively selects a subset of regressors when dealing with high dimensional data and/or collinearity in linear regression. As the name depicts it, high dimensional data occurs when the number of predictor variables is far …


Computational Analysis Of Large-Scale Trends And Dynamics In Eukaryotic Protein Family Evolution, Joseph Boehm Ahrens Mar 2019

Computational Analysis Of Large-Scale Trends And Dynamics In Eukaryotic Protein Family Evolution, Joseph Boehm Ahrens

FIU Electronic Theses and Dissertations

The myriad protein-coding genes found in present-day eukaryotes arose from a combination of speciation and gene duplication events, spanning more than one billion years of evolution. Notably, as these proteins evolved, the individual residues at each site in their amino acid sequences were replaced at markedly different rates. The relationship between protein structure, protein function, and site-specific rates of amino acid replacement is a topic of ongoing research. Additionally, there is much interest in the different evolutionary constraints imposed on sequences related by speciation (orthologs) versus sequences related by gene duplication (paralogs). A principal aim of this dissertation is to …


Cloud Workload Allocation Approaches For Quality Of Service Guarantee And Cybersecurity Risk Management, Soamar Homsi Mar 2019

Cloud Workload Allocation Approaches For Quality Of Service Guarantee And Cybersecurity Risk Management, Soamar Homsi

FIU Electronic Theses and Dissertations

It has become a dominant trend in industry to adopt cloud computing --thanks to its unique advantages in flexibility, scalability, elasticity and cost efficiency -- for providing online cloud services over the Internet using large-scale data centers. In the meantime, the relentless increase in demand for affordable and high-quality cloud-based services, for individuals and businesses, has led to tremendously high power consumption and operating expense and thus has posed pressing challenges on cloud service providers in finding efficient resource allocation policies.

Allowing several services or Virtual Machines (VMs) to commonly share the cloud's infrastructure enables cloud providers to optimize resource …


Context-Aware Personalized Point-Of-Interest Recommendation System, Ramesh Raj Baral Feb 2019

Context-Aware Personalized Point-Of-Interest Recommendation System, Ramesh Raj Baral

FIU Electronic Theses and Dissertations

The increasing volume of information has created overwhelming challenges to extract the relevant items manually. Fortunately, the online systems, such as e-commerce (e.g., Amazon), location-based social networks (LBSNs) (e.g., Facebook) among many others have the ability to track end users' browsing and consumption experiences. Such explicit experiences (e.g., ratings) and many implicit contexts (e.g., social, spatial, temporal, and categorical) are useful in preference elicitation and recommendation. As an emerging branch of information filtering, the recommendation systems are already popular in many domains, such as movies (e.g., YouTube), music (e.g., Pandora), and Point-of-Interest (POI) (e.g., Yelp).

The POI domain has many …


The Use Of Elemental Databases In Forensic Science: Studies On Vehicle Glass Interpretation And Milk Powder Provenancing, Tricia Marie Hoffman May 2018

The Use Of Elemental Databases In Forensic Science: Studies On Vehicle Glass Interpretation And Milk Powder Provenancing, Tricia Marie Hoffman

FIU Electronic Theses and Dissertations

The first study focuses on the development of a laser based method for the elemental analysis of solid milk powder. Milk powder samples originating from five different countries were analyzed to determine any geographic differences. A LA-ICP-MS method was developed and compared to k0-INAA for several milk samples as well as a reference sample. Precision of 10% RSD or better and a bias of 10% was achieved for both techniques for most elements with LA-ICP-MS producing lower limits of detection (~ 1 ppm) for Sr. The comparison of LA-ICP-MS to k0-INAA showed overlap of the 95% …


Exposure To Estrogenic Endocrine Disrupting Chemicals And Brain Health, Mark Preciados May 2018

Exposure To Estrogenic Endocrine Disrupting Chemicals And Brain Health, Mark Preciados

FIU Electronic Theses and Dissertations

The overall objective of this dissertation was to examine exposures to the estrogenic endocrine disrupting chemicals (EEDCs), phthalates, bisphenol-A (BPA), and the metalloestrogens cadmium (Cd), arsenic (As), and manganese (Mn) in an older geriatric aged-population and examine associations with brain health. Given the evidence that EEDCs affect brain health and play a role in the development of cognitive dysfunction and neurodegenerative disease, and the constant environmental exposure through foods and everyday products has led this to becoming a great public health concern. Using a bioinformatic approach to find nuclear respiratory factor 1 (NRF1) gene targets involved in mitochondrial dysfunction, that …


User-Centric Privacy Preservation In Mobile And Location-Aware Applications, Mingming Guo Apr 2018

User-Centric Privacy Preservation In Mobile And Location-Aware Applications, Mingming Guo

FIU Electronic Theses and Dissertations

The mobile and wireless community has brought a significant growth of location-aware devices including smart phones, connected vehicles and IoT devices. The combination of location-aware sensing, data processing and wireless communication in these devices leads to the rapid development of mobile and location-aware applications. Meanwhile, user privacy is becoming an indispensable concern. These mobile and location-aware applications, which collect data from mobile sensors carried by users or vehicles, return valuable data collection services (e.g., health condition monitoring, traffic monitoring, and natural disaster forecasting) in real time. The sequential spatial-temporal data queries sent by users provide their location trajectory information. The …


Sabermetrics - Statistical Modeling Of Run Creation And Prevention In Baseball, Parker Chernoff Mar 2018

Sabermetrics - Statistical Modeling Of Run Creation And Prevention In Baseball, Parker Chernoff

FIU Electronic Theses and Dissertations

The focus of this thesis was to investigate which baseball metrics are most conducive to run creation and prevention. Stepwise regression and Liu estimation were used to formulate two models for the dependent variables and also used for cross validation. Finally, the predicted values were fed into the Pythagorean Expectation formula to predict a team’s most important goal: winning.

Each model fit strongly and collinearity amongst offensive predictors was considered using variance inflation factors. Hits, walks, and home runs allowed, infield putouts, errors, defense-independent earned run average ratio, defensive efficiency ratio, saves, runners left on base, shutouts, and walks per …


On Some Ridge Regression Estimators For Logistic Regression Models, Ulyana P. Williams Mar 2018

On Some Ridge Regression Estimators For Logistic Regression Models, Ulyana P. Williams

FIU Electronic Theses and Dissertations

The purpose of this research is to investigate the performance of some ridge regression estimators for the logistic regression model in the presence of moderate to high correlation among the explanatory variables. As a performance criterion, we use the mean square error (MSE), the mean absolute percentage error (MAPE), the magnitude of bias, and the percentage of times the ridge regression estimator produces a higher MSE than the maximum likelihood estimator. A Monto Carlo simulation study has been executed to compare the performance of the ridge regression estimators under different experimental conditions. The degree of correlation, sample size, number of …


On The Performance Of Some Poisson Ridge Regression Estimators, Cynthia Zaldivar Mar 2018

On The Performance Of Some Poisson Ridge Regression Estimators, Cynthia Zaldivar

FIU Electronic Theses and Dissertations

Multiple regression models play an important role in analyzing and making predictions about data. Prediction accuracy becomes lower when two or more explanatory variables in the model are highly correlated. One solution is to use ridge regression. The purpose of this thesis is to study the performance of available ridge regression estimators for Poisson regression models in the presence of moderately to highly correlated variables. As performance criteria, we use mean square error (MSE), mean absolute percentage error (MAPE), and percentage of times the maximum likelihood (ML) estimator produces a higher MSE than the ridge regression estimator. A Monte Carlo …


An Investigation Of The Effects Of Taking Remedial Math In College On Degree Attainment And College Gpa Using Multiple Imputation And Propensity Score Matching, Meghan A. Clovis Mar 2018

An Investigation Of The Effects Of Taking Remedial Math In College On Degree Attainment And College Gpa Using Multiple Imputation And Propensity Score Matching, Meghan A. Clovis

FIU Electronic Theses and Dissertations

Enrollment in degree-granting postsecondary institutions in the U.S. is increasing, as are the numbers of students entering academically underprepared. Students in remedial mathematics represent the largest percentage of total enrollment in remedial courses, and national statistics indicate that less than half of these students pass all of the remedial math courses in which they enroll. In response to the low pass rates, numerous studies have been conducted into the use of alternative modes of instruction to increase passing rates. Despite myriad studies into course redesign, passing rates have seen no large-scale improvement. Lacking is a thorough investigation into preexisting differences …


Trend And Acceleration: A Multi-Model Approach To Key West Sea Level Rise, John Tenenholtz Nov 2017

Trend And Acceleration: A Multi-Model Approach To Key West Sea Level Rise, John Tenenholtz

FIU Electronic Theses and Dissertations

Sea level rise (SLR) varies depending on location. It is therefore important to local residents, businesses and government to analyze SLR locally. Further, because of increasing ice melt and other effects of climate change, rates of SLR may change. It is therefore also important to evaluate rates of change of SLR, which we call sea level acceleration (SLA) or deceleration.

The present thesis will review the annual average sea level data compiled at the Key West tidal gauge in Key West, Florida. We use a multi-model approach that compares the results of various models on that data set. The goal …


A Comparison Of Some Confidence Intervals For Estimating The Kurtosis Parameter, Guensley Jerome Jun 2017

A Comparison Of Some Confidence Intervals For Estimating The Kurtosis Parameter, Guensley Jerome

FIU Electronic Theses and Dissertations

Several methods have been proposed to estimate the kurtosis of a distribution. The three common estimators are: g2, G2 and b2. This thesis addressed the performance of these estimators by comparing them under the same simulation environments and conditions. The performance of these estimators are compared through confidence intervals by determining the average width and probabilities of capturing the kurtosis parameter of a distribution. We considered and compared classical and non-parametric methods in constructing these intervals. Classical method assumes normality to construct the confidence intervals while the non-parametric methods rely on bootstrap techniques. The bootstrap …


Maximum Likelihood Estimation Of Parameters In Exponential Power Distribution With Upper Record Values, Tianchen Zhi Mar 2017

Maximum Likelihood Estimation Of Parameters In Exponential Power Distribution With Upper Record Values, Tianchen Zhi

FIU Electronic Theses and Dissertations

The exponential power (EP) distribution is a very important distribution that was used by survival analysis and related with asymmetrical EP distribution. Many researchers have discussed statistical inference about the parameters in EP distribution using i.i.d random samples. However, sometimes available data might contain only record values, or it is more convenient for researchers to collect record values. We aim to resolve this problem. We estimated two parameters of the EP distribution by MLE using upper record values. According to simulation study, we used the Bias and MSE of the estimators for studying the efficiency of the proposed estimation method. …


The Interactions Of Relationships, Interest, And Self-Efficacy In Undergraduate Physics, Remy Dou Mar 2017

The Interactions Of Relationships, Interest, And Self-Efficacy In Undergraduate Physics, Remy Dou

FIU Electronic Theses and Dissertations

This collected papers dissertation explores students’ academic interactions in an active learning, introductory physics settings as they relate to the development of physics self-efficacy and interest. The motivation for this work extends from the national call to increase participation of students in the pursuit of science, technology, engineering, and mathematics (STEM) careers. Self-efficacy and interest are factors that play prominent roles in popular, evidence-based, career theories, including the Social cognitive career theory (SCCT) and the identity framework. Understanding how these constructs develop in light of the most pervasive characteristic of the active learning introductory physics classroom (i.e., peer-to-peer interactions) has …


The Impacts Of Telecommuting On The Time-Space Distribution Of Daily Activities, Mario Benito Rojas Iv Nov 2016

The Impacts Of Telecommuting On The Time-Space Distribution Of Daily Activities, Mario Benito Rojas Iv

FIU Electronic Theses and Dissertations

As major cities have aged, they have also met or exceeded their transportation infrastructure’s capacity. This has led to many negative impacts such as increased greenhouse gas emissions, delay, travel time, congestion, as well as decreased energy independence, standard of living for the cities’ inhabitants and the world as a whole. As a result, these cities will undoubtedly suffer and will struggle to meet the needs of their citizens. It is becoming more evident, and relevant, that the solution to today’s and tomorrow’s transportation problems will be overcome through the use of policy as well as innovative strategies, one of …


Biogeographical Patterns Of Soil Microbial Communities: Ecological, Structural, And Functional Diversity And Their Application To Soil Provenance, Natalie Damaso Oct 2016

Biogeographical Patterns Of Soil Microbial Communities: Ecological, Structural, And Functional Diversity And Their Application To Soil Provenance, Natalie Damaso

FIU Electronic Theses and Dissertations

The current ecological hypothesis states that the soil type (e.g., chemical and physical properties) determines which microbes occupy a particular soil and provides the foundation for soil provenance studies. As human profiles are used to determine a match between evidence from a crime scene and a suspect, a soil microbial profile can be used to determine a match between soil found on the suspect’s shoes or clothing to the soil at a crime scene. However, for a robust tool to be applied in forensic application, an understanding of the uncertainty associated with any comparisons and the parameters that can significantly …


On Some Test Statistics For Testing The Population Skewness And Kurtosis: An Empirical Study, Yawen Guo Aug 2016

On Some Test Statistics For Testing The Population Skewness And Kurtosis: An Empirical Study, Yawen Guo

FIU Electronic Theses and Dissertations

The purpose of this thesis is to propose some test statistics for testing the skewness and kurtosis parameters of a distribution, not limited to a normal distribution. Since a theoretical comparison is not possible, a simulation study has been conducted to compare the performance of the test statistics. We have compared both parametric methods (classical method with normality assumption) and non-parametric methods (bootstrap in Bias Corrected Standard Method, Efron’s Percentile Method, Hall’s Percentile Method and Bias Corrected Percentile Method). Our simulation results for testing the skewness parameter indicate that the power of the tests differs significantly across sample sizes, the …