Statistical Methodology Commons^™

Hybrid Patchtst And Physics-Based Framework For Predicting Lithium-Ion Battery State Of Health, Pavan Ravuri

Honors Undergraduate Theses

Accurately forecasting the state of health of lithium-ion batteries is critical for improving performance, reliability and lifetime in energy storage applications. Battery capacity degrades into a nonlinear pattern over cycling due to electrochemical processes where neither purely data driven nor physics-based models can capture alone. This study looks at a hybrid framework combining that PatchTST patch-based transformer architecture with physics-based features derived from the solid electrolyte interphase and pseudo two-dimensional models. Physics inspired proxy features were computed from cycling data and concatenated with electrochemical measurements as added input channels before patch segmentation. There are five model configurations that were evaluated …

An Integrated Data-Driven Framework For Arctic Shipping: Analyzing Vessel Speed, Environmental And Ecological Factors Through Innovative Statistical Spatio-Temporal Methods, Inverse Optimization And Machine Learning, Mauli Pant

Theses and Dissertations

This dissertation develops an integrated data-driven framework to analyze vessel navigation and ecological risk in the United States Arctic from 2010 to 2019. As environmental change and maritime activity increase in the region, understanding how vessels respond to dynamic conditions and how those responses interact with marine ecosystems has become increasingly important. A central theme of this dissertation is the treatment of vessel speed as both an observed outcome and a decision variable reflecting trade- offs among operational, environmental, and ecological factors. The first chapter develops a predictive framework for vessel speed over ground (SOG) using Gaussian Process Boosting (GPBoost), …

Machine Learning-Based Spatio-Temporal Modeling Of Climate Dynamics And Desertification In The Sahara–Sahel Region, Stephen M. Tivenan

Theses and Dissertations

Arid climate classifications are threshold-dependent and easily interpretable mappings that are widely used in ecological, agricultural, and climate-related studies. These classifications inform scientific understanding, support policy and land management decisions, and provide an intuitive summary of environmental conditions. Despite their usefulness, traditional arid climate classifications often fail to quantify uncertainty, incorporate spatial context, or account for complex relationships among relevant environmental variables. Existing approaches to uncertainty assessment have largely relied on comparing classifications across multiple datasets or alternative formulas, but these methods generally overlook important spatial dependence and latent structure in the data.

This dissertation develops three machine learning-based statistical …

A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra

Graduate Theses/Dissertations

Groundwater salinization poses a critical environmental concern for water resource sustainability in arid and semi-arid regions. This study evaluates spatial and temporal patterns of groundwater salinity across the state of Durango, Mexico, using total dissolved solids (TDS), sodium adsorption ratio (SAR), as salinity indicators and nitrate-nitrogen (NO₃–N) as an anthropogenic indicator. Groundwater quality data were obtained from (CONAGUA), a Mexican water agency. To assess salinity variations with respect to time, while minimizing interannual sampling bias, two multi-year sampling periods were selected: 2012-2013, and 2020-2021. Final datasets consisted of 122 wells for 2012–2013 and 131 wells for 2020–2021. The wells were …

A Comparative Evaluation Of Data Imbalance Handling Techniques In Machine Learning Models For One-Year Mortality Prediction In Liver Cirrhosis, Sumiya Hasan Trisha

UNF Graduate Theses and Dissertations

Liver cirrhosis is associated with substantial morbidity and mortality, making one-year mortality prediction a clinically relevant problem. Using a liver cirrhosis dataset as the motivating application, this thesis evaluates five machine learning classifiers—Logistic Regression, Random Forest, XGBoost, LightGBM, and CatBoost—under five class-imbalance handling strategies: Baseline learning, Random Oversampling, SMOTE-NC, ADASYN, and Cost-Sensitive Learning. Hyperparameter tuning was conducted using randomized search, and predictive performance was assessed over 200 iterations of Monte Carlo Cross-Validation using Accuracy, Precision, Recall, Fl-score, and ROC-AUC.

The results suggest that imbalance-handling strategies can materially affect predictive performance, particularly recall. Because the outcome of interest is death within …

Variance Shrinkage In Dunnett-Type Multiple Comparisons With Missing Data, Md Habibullah

UNF Graduate Theses and Dissertations

Dunnett’s procedure is widely used for comparing multiple treatments with a control, but its application becomes challenging in the presence of missing data and multiple com- parisons. An improved Dunnett-type procedure addresses this by using multiple imputation under Rubin’s framework and constructing unified confidence intervals based on a multi- variate t distribution, allowing valid simultaneous inference while controlling the family-wise error rate (FWER). This work further extends the method by incorporating shrinkage-based variance estimation. Specifically, individual group variances are shrunk toward a common value to improve stability. This approach is particularly effective when group variances are similar or moderately different, …

Ridit-Based Adaptive Allocation In Two-Stage Clinical Trials With Binary Outcomes, Dewan Fahim

UNF Graduate Theses and Dissertations

This study explores better ways to assign patients to treatments in clinical trials with binary outcomes, such as success or failure. Adaptive methods are used to learn from early results and adjust treatment assignments during the trial, helping more patients receive better performing treatments while maintaining reliable conclusions. We focus on trials comparing multiple treatments using a two-stage design. In the first stage, several treatments are tested to identify the most promising one; in the second stage, that treatment is compared with a control. Unlike traditional equal assignment, we use adaptive allocation in the second stage to make better use …

A Comparative Study Of Classification Methods For Healthcare Analytics, Xueting Zhao

UNF Graduate Theses and Dissertations

This thesis presents a comparative study of logistic regression, Linear Discriminant Analy- sis (LDA), and Quadratic Discriminant Analysis (QDA) for binary classification in healthcare analytics, integrating theoretical derivation, simulation, and real-data application. A facto- rial simulation study crosses the covariance structure (equal vs. unequal), predictor correla- tion (ρ ∈ {0, 0.5, 0.9}), dimensionality (p ∈ {2, 5, 10}) and sample size (n ∈ {50, 100, 200}) across 54 scenarios with 1,000 Monte Carlo replicates each. Three main findings emerge. Logistic regression and LDA are nearly interchangeable when the assumption of equal-covariance holds. QDA achieves substantially better discrimi- nation when class-specific …

Two-Stage Response-Adaptive Randomization Designs For Multi-Arm Trials With Normal Outcome, Tanjin Tamanna Happy

UNF Graduate Theses and Dissertations

This study focuses on improving how clinical trials compare new treatments with a standard treatment, when the response is quantitative (normally distributed). In a common two-stage design, several new treatments are first evaluated, and the best-performing one is selected if it appears better than the standard. In the second stage, this selected treatment is compared again with the standard using additional data to confirm its effectiveness. This approach is known to be efficient in terms of accuracy and sample size savings. We extend this design by introducing an adaptive method for assigning patients to treatments in the second stage. Instead …

Statistical Quality Control: A Bayesian Framework, Jakia Jaber Tunal

College of Graduate Studies: Theses & Dissertations

In many industries, it is important to assess whether a machine or system is operating within acceptable limits or has gone out of control. This project applies Bayesian statistics to monitor a process over time and detect changes in its behavior. First, initial data are collected to understand the system’s typical performance and to form a starting prior distribution. As new observations arrive over time, the prior is updated through Bayesian inference, combining past information with incoming data. This iterative updating creates a continuous monitoring framework that adapts as more evidence becomes available. When the updated results suggest that the …

Shaking Table Test And Numerical Simulation Of Seismic Response Characteristics Of Rock Slope With Muddy Interlayer, Duan Chenggang, Fang Yanlin, Tian Yeqing, Zhou Zhijun

Journal of China & Foreign Highway

In order to study the seismic macroscopic failure process and dynamic response characteristics of rock slope with muddy interlayer and reveal the influence of muddy interlayer on slope stability,a similar slope model with concave and convex slope types was designed,and shaking table test was carried out;finite element analysis was used for numerical modeling analysis,and the results obtained by the two models were compared.The results show that:① The macroscopic deformation and failure process of the model slope is divided into three stages.Muddy interlayer dislocates,and cracks occur;mud interlayer slips,and cracks expand;slope collapses;② The seismic load has a decisive influence on the stability …

Effect Of Lithium Slag Dosage On Strength And Dry Shrinkage Properties Of Cement Stabilized Recycled Macadam, Zhao Ziyu, Gan Xianyong

Journal of China & Foreign Highway

To improve the mechanical properties and dry shrinkage properties of cement stabilized bases formed by cold in-place recycling of cement concrete pavements,lithium slag was mixed into the recycled mixture in mass ratios of 0%,6%,9%,and 12%.The effects of lithium slag dosage on the mechanical,dry shrinkage,and water stability properties of the recycled base were analyzed through the unconfined compressive strength,splitting,dry shrinkage,and water stability tests,and the mechanism underlying the improving effect of lithium slag on the cement stabilized base formed by cold in-place recycling of the cement concrete pavement was analyzed by X-ray diffraction (XRD ) and scanning electron microscopy (SEM ).The results …

Optimization Of Infill Concrete Dimension In Composite Girder Box Based On Igrnn, Wang Yafeng, Liu Jian, Ke Hongjun

Journal of China & Foreign Highway

The mechanical performance of the negative bending moment zone of steel-concrete composite continuous girders has always been a focus of attention in bridge engineering.Existing research mainly proposes improvement measures for the tension of concrete bridge decks,while paying little attention to the common phenomenon of steel girders bearing pressure.The steel girders in steel-concrete composite girders,especially the steel bottom plate in the negative bending moment area of the pier top,bear the highest compressive stress of the entire bridge.Therefore,by taking a steel-concrete composite girder bridge in Zhejiang Province as the engineering background,it is proposed to partially fill the interior of the box girder …

Research On Cable Force Optimization Of Long-Span Cable-Stayed Bridges Based On Rbfnn+Improved Parti Cle Swarm Optimization Algorithm, Deng Da, He Bowen, Liu Guokun

Journal of China & Foreign Highway

In view of the cable force optimization problem of long-span cable-stayed bridges,a cable force optimization method considering the reliability index of stay cables was proposed based on the response surface fitted by the radial basis function neural network (RBFNN ).The RBFNN-based response surface model for solving the reliability index was established by fitting the structural implicit function through RBFNN training.The improved particle swarm optimization algorithm was used to search for the optimal solution of the cable force optimization model considering the reliability index.The research results show that RBFNN can accurately predict the structural responses and fit the structural implicit performance …

Design Optimization And Experimental Study Of Cfrp Plate Anchorage With Clip-Extension Type, Qi Yijia, Xiao Dan, Wang Zhongqiang

Journal of China & Foreign Highway

Existing anchorage is prone to damaging the carbon-fiber reinforced polymer (CFRP ) plate due to the “notch effect ” and uneven distribution of clamping stress.This study proposed a new clip-extension type anchorage for the CFRP plate.This design utilized the ductility of steel for stress diffusion and guided the compressive stress zone in the CFRP plate away from the notched end,realizing a smooth transition of the clamping force of the CFRP plate at the clip port and effectively reducing the “notch effect ”.The design also reduced the strain difference between the carbon fibers,resulting in a more synchronized lateral deformation of the …

Research And Applicat Ion Of Ultra Large-Scale Consolidated Under-Reamed Drilled Shaft Technology Under Special Environmental And Geological Conditions, Ding Yi, Yu Kun, Shi Haiyang, Pei Xiaofeng, Zhu Bo

Journal of China & Foreign Highway

This article aims to add ress the poor economic efficiency of large-diameter and ultra-long piles,the high risk of hole collapse in thick sandy soil,and the limited space across the canal faced by the Bridge over Yellow River Diversion to Qindao Canal on Zhanhua ‒ Linyi Expressway.According to the comparison of conventional drilled cast-in-place piles with combined pile-end and pile-side post-grouting,the industry ’s under-reamed drilled shaft foundation with the largest disc diameter (4.5 m) and the largest single-pile volume (456 m3) was proposed and designed.At the same time,supporting devices such as three-arm rotary cutting drill bits and long arm borehole diameter …

Analysis Of Influence Of Internal Erosion On Deformation Of Subway Station Structure, Qin Tianxin, Wang Chen, Tan Xuyan, Wei Shengming, Liang Fayun

Journal of China & Foreign Highway

Under the long-term effects of disasters such as rainstorms and floods,the soil layer around subway stations may be affected by internal erosion,threatening the structural safety of urban subway stations.To explore the influence of internal erosion on subway station structures,this study conducted isotropic consolidation and triaxial compression tests on gap-graded sand soil.Eroded soil specimens were simulated by adjusting the fine particle content to explore the pattern of variations in physical and mechanical properties caused by internal erosion.Results indicate that internal erosion alters the stress-strain relationship of gap-graded sand soil,increasing compressibility,decreasing shear strength,and weakening dilatancy.Drucker-Prager (DP) cap model parameters for eroded sand …

Evaluation Method For Nighttime Visual Space Improvement On Mountain Roads, Zhao Yan, Chen Yanli, Chen Jiale

Journal of China & Foreign Highway

To address issues such as poor visual guidance,narrow field of view,and short sight distance during nighttime driving on mountain roads,this study proposed a visual space enhancement evaluation method applicable to mountainous roads at night.By integrating active and passive traffic safety facilities,a visual space enhancement strategy adapted to the nighttime environment of mountain roads was proposed.A multidimensional evaluation indicator for visual space was established based on co-simulation.The effectiveness of the strategy was verified from the perspectives of visual space expansion and driving safety improvement by taking a trunk highway in the Qinling mountainous region as a case study.The results show that …

Utilization Technology And Compaction Quality Control Of Hardened Layer In Beam Yard Of Rock-Filled Roadbed, Cheng Xiaoliang, Tian Wendi, Gao Mengke, Zhou Xujia

Journal of China & Foreign Highway

To investigate the utilization technology and compaction quality control of hardened layers in the beam yard of rock-filled roadbed,the optimization design and construction control methods for rock-filled roadbed under different conditions were proposed based on a highway project in Guangdong Province.When the elevation of the hardened layer was lower than the top surface elevation of the roadbed and the top surface bending and settlement value of the hardened layer was less than that of the rock-filled roadbed,the gravel material could be filled directly on the hardened layer to the top surface elevation of the roadbed,and acceptance and pavement design could …

Reflection Cracking Resistance And Fatigue Performance Of Super-Flexible Fma Mixture, Lan Yong, Deng Xinghe, Zhang Zida, Wu Kuanghuai, Ding Weizhe, Guan Xuebing, Peng Tiekun

Journal of China & Foreign Highway

To investigate the fatigue performance and reflection cracking resistance of super-flexible fluid mastic asphalt (FMA ) mixtures,this study designed a super-flexible FMA- 13 mixture by the mastic flow for filling (MaFF ) method.The effects of temperature and maximum horizontal tensile displacement on the cracking resistance of both FMA- 13 and GAC- 13 (as the control ) mixtures were explored via the Overlay Tester.Additionally,small-scale accelerated pavement loading tests were conducted to analyze the effect of load cycles on the rebound modulus of the FMA- 13 mixture.A nonlinear fatigue damage model was employed to predict the fatigue life of both mixtures.The results …