Digital Commons Network^™

Marine Ecosystem Services Disruption And Social Violence, Rafael Hurtado-Valdivieso

Graduate Thesis and Dissertation post-2024

Over the past century, human activities have profoundly altered ocean and coastal ecosystems, significantly impacting communities whose livelihoods depend on these environments. This dissertation explores how disruptions in marine ecosystem services contribute to the emergence of social violence in coastal communities, with a specific focus on the Colombian Caribbean. While prior research suggests a potential link between environmental degradation and conflict, empirical evidence remains limited and inconclusive. This study addresses that gap through a multi-method, interdisciplinary approach that integrates environmental science, political science, and computational modeling to examine the mechanisms linking ecosystem disruption to social violence.

The research follows a …

Bridging Data Gaps And Forecasting Challenges In Water Quality Monitoring Using Deep Learning, Rohan Gudla

Graduate Thesis and Dissertation post-2024

Reliable water quality monitoring is critical for protecting public health and enabling sustainable environmental management. However, high rates of missing data often exceed 40% due to sensor failures and operational disruptions severely undermine the utility of environmental monitoring systems. To address this challenge, this thesis presents a three-stage deep learning framework designed to enhance the accuracy and resilience of water quality forecasting. First, a Bidirectional Long Short-Term Memory model with Attention and Autoencoder Modules (BiLSTM-AAM) is introduced to impute long, irregular gaps in multivariate time series. Applied to real-world data from the St. Lucie River Basin, the model achieved a …

Enhancing Intelligent Transportation Systems: Scalability, Emulation, And Applications Of V2x Communication For Connected And Autonomous Vehicles, Ghayoor Shah

Graduate Thesis and Dissertation post-2024

The integration of Vehicle-to-Everything (V2X) communication is a key advancement for Connected and Autonomous Vehicles (CAVs), enhancing the safety, efficiency, and intelligence of modern Intelligent Transportation Systems (ITS). While Autonomous Vehicles (AVs) rely heavily on onboard sensor data for situational awareness, they remain limited in non-line-of-sight scenarios, which can lead to critical driver errors and accidents. V2X communication extends this awareness by enabling real-time exchange of information beyond sensor range, improving decision-making and reducing collisions.

Two primary V2X technologies are Dedicated Short-Range Communication (DSRC) and Cellular-V2X (C-V2X). While DSRC, based on IEEE 802.11p, was initially prominent in research, C-V2X, standardized …

Accurate And Efficient Orbit Probability Approximation Framework For Space Situational Awareness, Pugazhenthi Sivasankar

Graduate Thesis and Dissertation post-2024

Uncertainty Propagation in astrodynamics has gained importance in space situational awareness (SSA) problems such as space debris tracking, collision avoidance, and Cislunar operations. In this dissertation, the technique of Orbit Probability Approximation (OPA) is developed. OPA propagates orbital uncertainty using Liouville’s theorem with different functional approximations. First, OPA is formulated with Chebyshev polynomials to propagate the uncertainty on a geocentric planar orbit problem and then validated using two sources of satellite data: GRACE navigation data from the Jet Propulsion Laboratory (JPL) database, and FireOPAL ground-based observer provided by Lockheed Martin. In this validation process, OPA propagates uncertainty without using any …

Computational Approaches For Rna Structural Motif Analysis: Similarities, Variations, And Spatial Relationships, Md Mahfuzur Rahaman

Graduate Thesis and Dissertation post-2024

The three-dimensional structures of RNA play a critical role in understanding their functions. One way to study the RNA 3D structure is by analyzing recurrent segments within the loop regions of RNAs, known as RNA structural motifs. These motifs can be grouped into families based on their structural features. However, the inherent structural diversity presents challenges in characterizing the similarities, variations, and spatial relationships within RNA motif families. This dissertation presents three computational methods that together provide a comprehensive framework for RNA structural motif analysis. First, RNAMotifComp establishes and visualizes relational networks among structural motif families. By analyzing instances of …

From Failure To Fidelity: Enabling Scalable Sim2real Lidar Perception Through Realistic Digital Twins, Muhammad Shahbaz

Graduate Thesis and Dissertation post-2024

LiDAR technology plays a key role in enabling intelligent perception across urban systems. Its ability to capture accurate 3D data regardless of lighting conditions makes it well-suited for applications in autonomous vehicles, traffic monitoring, security, and privacy-aware smart city infrastructure, offering advantages over camera-based systems in depth, precision, and reliability. However, scaling deployment faces substantial challenges due to the time, effort, and cost of gathering and labeling LiDAR data used to train and test perception algorithms. This dissertation addresses these challenges by tracing a comprehensive research trajectory from early failures to a successful, fidelity-driven solution. Initially, (1) it explores transfer …

"Please Hold Space For Them": The Role Of Mental Health Professionals In Supporting Bipoc Female Survivors Of Campus Sexual Assault, Brianna Josefine Ortega

Doctoral Dissertations

Campus sexual assault (CSA) remains a pervasive issue in the United States, disproportionately affecting women. Despite this, the experiences of Black, Indigenous, and other Persons of Color (BIPOC) women are often underrepresented in the literature, limiting understanding of how best to support them. Based on intersectionality theory, this qualitative study explores how mental health professionals (MHPs) support BIPOC female survivors of CSA. Semi-structured interviews were conducted with six MHPs, and a thematic analysis framework uncovered seven key themes: disclosure (subtheme: barriers to disclosure), impacts of campus culture, fear and distrust, impact of campus sexual assault, coping, resources available for survivors, …

American Muslim Women’S Experiences With Pregnancy And Childbirth In The United States Healthcare System, Salema Mohamed

Graduate Thesis and Dissertation post-2024

Muslim women adhere to specific religious beliefs and practices, which can inform their healthcare decisions and requirements during pregnancy and childbirth. Despite an increase in the Muslim population in the U.S., there is currently limited research on Muslim women's maternity care and experiences. To address the gaps in knowledge, this study explored Muslim women’s experiences with pregnancy and childbirth in the U.S. Data consists of interviews from 20 Muslim women who had pregnancy and childbirth in the U.S. A thematic analysis was used to analyze and report the findings. The findings revealed that modesty was a significant concern during pregnancy …

“Rights Not Rescue”: How Stigma Influences Harmful Legislation Toward Sex Workers In The Deep South, Abigail Mckenzie Conover

Graduate Thesis and Dissertation post-2024

In the United States, while prostitution or sex work is not explicitly illegal at a federal level, certain characteristics have been criminalized, mainly in indirect ways. This is significant when considering the different ways that sex work is regarded (both positively and negatively) at an institutional level. The current study examines the potential correlation between structural/institutional stigma regarding sex work/sex workers and legislation meant to directly or indirectly harm sex workers. The overall goal of this research was to answer the following question: How does structural/institutional stigma against sex workers present itself in legislation? To accomplish this, I conducted a …

The Association Between The Social Determinants Of Health And Shared Decision Making: An Investigation Of The National Survey Of Children's Health, Vernon T. Headley

Graduate Thesis and Dissertation post-2024

Objective: Shared decision-making (SDM) is defined as a clinical approach that allows both physicians and patients to communicate on the best treatment options that will improve the patient's overall health outcomes. Shared decision-making plays a vital role in how parents engage with their physicians regarding the healthcare needs of their children. This dissertation assessed the association between the social determinants of health and shared decision-making regarding children’s health-related issues.

Methods: The data for the current research were the National Survey of Children’s Health (NSCH), combined 2017-2020. The dependent variable was shared decision-making and included discussing treatment options, raising concerns regarding …

Podcast Narratives Of Cybercrime Perpetration, Rebeka Rocco

Graduate Thesis and Dissertation post-2024

The growth of the internet and cybertechnology has created the opportunity for new types of crime. Given the recency of these developments, little is known about cybercrime perpetration and there is scant existing data gathered from those who have perpetrated cybercrime. This project applied thematic analysis to 30 episodes of a popular podcast focused on cybercrime to explore pathways men take to committing and continuing to commit cybercrimes against networks and information, financial cybercrime, and sales of products on illegal online marketplaces. Findings suggest that podcast narratives of perpetration reveal shifting motivations, gradual immersion in online deviant and criminal communities, …

Nueva Metodología De Análisis Para Determinar El Delito Ambiental De Ecocidio Por Glifosato En Cultivos Permanentes De Coca En Colombia, Rosalina González Forero, Jerry H. Kavouras, Érika González Ruiz

Biology Department Faculty Articles

El crimen organizado transnacional ha sido nefasto para el territorio colombiano, en especial el asociado a la producción de coca en la última década, lo que ha generado impactos económicos y sociales debido al aumento del conflicto e inseguridad en las zonas de influencia del cultivo. Esto se debe a que en el 2023 se tenían 230 000 hectáreas sembradas, lo que representa el 20 % de la superficie del país, con un impacto ambiental no cuantificado en términos penales. Este requiere de acciones de entidades estatales, así como de cooperación internacional, para adaptar estrategias y poder judicializar estos delitos …

Settlement Calculation Method For Composite Foundations Reinforced With Geo-Encased Stone Columns, Long Jun, Tan Jingpeng

Journal of China & Foreign Highway

Geo-encased stone columns (GESCs ),known for their cost-effectiveness and simple construction,are widely employed in the reinforcement of soft soil foundations in practical engineering,and the analysis of their settlement serves as a crucial foundation for the design process.However,existing research mainly focuses on experimental and numerical methods,with relatively limited progress in theoretical calculations.Based on the load transfer mechanism of GESC-reinforced composite foundations and the bulging deformation of the pile body within a certain depth of the pile top under vertical loading,the reinforced zone was divided into a bulging section and a non-bulging section,and the total settlement of the pile was regarded as …

Study On Deformation Characteristics Induced By Deep Foundation Pit Excavation Sharing Diaphragm Wall With Existing Subway Station, Ling Tonghua, Zou Nanwei, Zhou Kun, Feng Wei, Wu Xing, Zhang Liang

Journal of China & Foreign Highway

To investigate the deformation induced by deep foundation pit excavation sharing a diaphragm wall with an existing subway station,this study took the foundation pit project of Gongming Square Station of Shenzhen Metro as an example.A three-dimensional numerical model was established by FLAC3D software to analyze the deformation characteristics of the surrounding ground surface,retaining structures,and the subway station during the excavation process.In addition,field monitoring was conducted to measure the vertical and horizontal displacements of the pit sidewall and the subway station sharing the diaphragm wall.The results show that after excavation,the ground surface settlement behind the retaining wall exhibits an approximately elliptical …

Study On Chloride Ion Diffusion Behavior In Cracked Cement Mortar With High Fly Ash Content, Liu Yang, Mao Shengzhe, Lu Naiwei

Journal of China & Foreign Highway

In order to explore the diffusion behavior of chloride ions in cracked cement mortar with high fly ash (FA) content,this study fabricated cement mortar specimens with different FA contents and crack widths by artificially prefabricating cracks.The chloride ion content in cracks was measured after natural soaking for 30 days and 60 days.The results show that the cracks accelerate the diffusion of chloride ions in cement mortar.The increase in the diffusion coefficient caused by 0.05 mm and 0.1 mm cracks is similar,while that caused by a 0.2 mm crack is significantly higher.After 30 days of soaking,the chloride ion content of the …

Relationship Between Fractal Characteristics And Shear Strength Of Highway Spoil Site Materials, Luo Shixin, Luo Hongming, Zou Fei, Cai Lei

Journal of China & Foreign Highway

Highway spoil features a wide range of particle sizes and poor gradation,and their strength characteristics serve as key factors affecting the stability of spoil slopes.To explore the relationship between fractal characteristics of particle size and strength,this study examined 21 spoil sites along the Guizhou section of the Duyun ‒ Shangri-La Expressway.Based on the field investigation,particle size analysis tests,and laboratory shear tests,the particle composition and shear strength parameters of spoil were obtained.Based on fractal theory,the fractal characteristics of particle size under different gradation scaling methods were analyzed,and the relationship between shear strength parameters and the fractal dimensions of particle size was …

Research On Improvement Of Adhesive Properties Of Asphalt And Granite Gravel, Li Yu, Zhang Yingxue, Qiu Chao, Wang Mo, Liu Li

Journal of China & Foreign Highway

In view of the poor adhesion of acidic granite gravel and asphalt and the shortage of alkaline stone in asphalt pavement in China ’s expressway construction,this study evaluated the improvement effects of schemes,including single use of amine anti-stripping agent DRD-K 1,single use of non-amine anti-stripping agent AMR- 3,single use of cement,and combined use of anti-stripping agent and cement,on the asphalt-aggregate adhesion properties.Through the tests of three major indexes before and after asphalt aging,aggregate adhesion test,and improved water immersion method,the adhesion of asphalt was evaluated,and the optimal amount for use was proposed.The results show that the non-amine anti-stripping agent AMR- 3 …

Factors Influencing Fatigue Damage In Manufactured Sand-Based Ecological Self-Compacting Concrete Pavement, Fu Suanzi, Li Hongyan

Journal of China & Foreign Highway

Ecological-self-compacting concrete (Eco-SCC ) pavements offer advantages such as reduced cement consumption,lower carbon emissions,and improved economic performance.However,their durability has not been sufficiently studied.Based on the literature review and fatigue test data,the fatigue parameters of Eco-SCC were determined using the Chaboche damage evolution model.A finite element model of fatigue damage in Eco-SCC pavement structures was established to compare the fatigue damage distribution under different loading positions,identify the unfavorable loading positions,and analyze the influence of slab thickness and modulus on the durability of Eco-SCC pavements.SCC plate thickness and modulus on the durability of Eco-SCC pavement.The results show that fatigue damage under different …

Adhesion Mechanism Of Geopolymer-Modified Emulsified Asphalt Slurry At Interface With Aggregate, Zhong Chao, Yang Hao, Lin Juntao, Xiao Yue

Journal of China & Foreign Highway

In order to investigate the adhesion mechanism at the interface between geopolymer-modified emulsified asphalt slurry and aggregate,the interfacial adhesion performance was studied by the molecular dynamics method and compared with that of cement-modified emulsified asphalt slurry.In addition,macro-scale splitting strength tests were performed for verification.The results indicate that van der Waals forces play a major role in the adhesion at the slurry-aggregate interface.Under equivalent mix ratios,the interfacial binding energy between the geopolymer-modified emulsified asphalt slurry and aggregate is 6.84% ‒19.99% higher than that of the cement system.The adhesion performance is closely related to the diffusion properties and atomic distribution of the …

Experimental Study On Workability Of Alkali-Activated Red Mud-Based Controlled Low-Strength Materials, Wu Yun, Fang Mingjing², Lin Zhiyang², Liu Zhengwei³, Beng Jianping³

Journal of China & Foreign Highway

This study aims to optimize the mix design of alkali-activated red mud-based controlled low-strength materials (CLSMs ) to enhance their applicability in road engineering backfilling.The effects of red mud content (20% ‒ 50%),water-to-solid ratio (0.30‒0.36),sand-to-soil ratio (7∶3‒4∶6),polycarboxylate superplasticizer (PEC ) dosage (0%‒2.1%),and fly ash to mineral powder ratio (5∶1‒0.5∶1) on the flowability and bleeding resistance of the materials were systematically investigated.The results are as follows:① The water-to-solid ratio significantly influences flowability.Increasing it to 0.32‒0.34 improves flowability by 39%‒78%,but when the ratio exceeds 0.34,the bleeding rate increases significantly (up to 4.89%);② When the red mud content is 30%‒40%,the high specific surface …

Damage Localization Of Simp Ly Supported Beams Based On Deflection Influence Surfaces Calculated By Three-Dimensional Boundary Face Method, Yin Xinfeng, Luo Zonghao, Yan Wanli, Kaiersaer ∙Tuerdi

Journal of China & Foreign Highway

The deflection influence surface (DIS) of a spatial structure is difficult to calculate using the existing two-dimensional boundary element method.To address this issue,a damage localization method based on DIS calculated using the three-dimensional boundary face method (BFM ) was proposed.A custom BFM program with an internal loop was developed,and the internal forces and deformations of a square plate and a supported T-beam structure were calculated using the static method.By specifying the domain of the order of a bivariate polynomial function (BPF ),a secondary optimization program for influence surfaces was established,and the DIS with the minimum mean square error was obtained.The …

Research On Construction Monitoring Of Continuous Rigid Frame Bridge Based On Knn Algorithm, Liu Jianlin, Pan Kai, Yang Gang, Wang Junming

Journal of China & Foreign Highway

To address common issues in bridge construction monitoring,such as sensor damage and failure in strain and displacement measurements,this study took the Nanliu Jialing River Bridge as a case and proposed a method based on the K-nearest neighbor (KNN ) algorithm to reconstruct missing construction monitoring data.ANSYS Workbench was used to establish a finite element model (FEM ) of the bridge construction process to verify the effectiveness of the KNN algorithm in the presence of missing bridge construction monitoring data.The results show:① KNN algorithm can assist in filling short-term data gaps caused by damage to strain and displacement sensors during bridge …

Shear Strength Test Of Uhpc-Nc Bonding Surface, Zhang Shichang, Yan Donghuang, Liu Yun, Yuan Sheng, Wang Shuo

Journal of China & Foreign Highway

As a cement-based composite material with excellent mechanical properties,ultra-high performance concrete (UHPC ) demonstrates outstanding performance in tensile and compressive strength,durability,and impermeability.This material is suitable for the reinforcement and repair of normal concrete (NC) bridge structures.To study the shear behavior of the UHPC-NC bonding interface and its reinforcement effect,this paper conducted interface shear tests using Z-shaped specimens and designed a total of six sets of comparative specimens.The influence of parameters such as the planted bar ratio,implantation depth,and bonding surface size on the shear strength was explored.Through experiments,the load –slip curve and the shear strength data were obtained.The results show that:① …

Field Measurement And Analysis Of Wind Characteristics At Xuefenghu Bridge Site, Yu Wenhao, Yi Lu

Journal of China & Foreign Highway

Wind field parameters at bridge sites serve as an important basis for wind-resistant bridge design.The terrain surrounding the Xuefenghu Bridge is unique-mountains flank both sides in the bridge-aligned direction,and the bridge spans the wide surface of the Zhexi Reservoir.In order to investigate the wind field characteristics under such complex topographic conditions,an observation,acquisition,and wireless data transmission system was established at the bridge site.A one-year in-situ wind measurement campaign was conducted,and the characteristics of average wind and fluctuating wind were deeply analyzed.The results show that the average wind speed at the bridge site generally follows a Weibull distribution,and the average wind direction …

Experimental Study On Shear Resistance Of Existing Prestressed Concrete Hollow Slabs, Lu Youfu, Di Jin, Qin Fengjiang, Sun Yifei

Journal of China & Foreign Highway

Prestressed concrete hollow slabs are widely used in small- and medium-sized span highway bridges in China.With the increase in load ratings,many hollow slab bridges built in early periods fail to meet the current specifications for shear bearing capacity.Nevertheless,these hollow slabs continue to function adequately under existing vehicle loads,making it essential to conduct an in-depth investigation into their shear bearing capacity.Shear bearing capacity tests were conducted on five 16 m-span hollow slabs dismantled from a renovation and expansion project,including three top slabs with a 15 cm cast-in-place concrete structural layer.Various parameters,such as load-displacement curves,web concrete strain,cracking loads,crack development patterns,failure modes,and ultimate …

Analysis Of Flexural Bearin G Ca Pacity Of Concrete Box Girders Reinforced With, Cfrp Mesh End Anchorshu Guihua

Journal of China & Foreign Highway

Carb on fiber reinforced polymer (CFRP ) composite s have significant advantages in the reinforcement of concrete structures.It is worth systematically studying the effect and mechanism of applying this material in embedded end-anchored reinforcement of concrete box girders on improving the load-bearing capacity of the component.Based on the Abaqus finite element analysis (FEA ) platform,two numerical analysis models considering slip contact and full bonding contact between CFRP mesh and polymer mortar were established.A full-scale concrete box girder model test was conducted for validation.The results show that the FEA results are in good agreement with the experimental results.The FEA model that …

Wind Tunnel Test On Wind-Resistant Performance Of Suspended Monorail Cable-Stayed Bridge, Chen Yujiang

Journal of China & Foreign Highway

To investigate the wind-induced vibration of a suspended monorail bridge,a full-bridge aeroelastic model at a 1∶40 scale was designed and fabricated according to the geometrical parameters and dynamic characteristics of the real bridge.Wind tunnel tests on the bridge in both the completed state and the maximum cantilever state were conducted under different conditions,including uniform flow and turbulent flow,yaw angles of ± 45°,±30°,±15°,and 0°,and wind attack angles of ‒ 3°,0°,and + 3°.Both vertical and torsional displacements of the structure under different wind speeds were measured.The test results show that the vertical displacements and torsional responses of the cable-stayed bridge increase when …

Research On Autonomous Deviation Correction Of Tunnel Boring Machines And Parameters Based On Machine Learning, Zhang Jun, Li Maopeng

Journal of China & Foreign Highway

In order to solve the problem of realizing the autonomous deviation correction of tunnel boring machines (TBMs ), a TBM deviation correction control method that integrated the random forest (RF) algorithm with the genetic algorithm (GA) was proposed based on actual engineering data.The method combined a prediction model with an optimization model,using target deviation values as input to invert and output the required TBM deviation correction parameter values,thereby further improving the automation level of TBM deviation correction.By comparing it with the actual data,the feasibility of the model was verified.The results show that the RF algorithm-based prediction model achieves an R2 …

Study On Mechanical Effect Of Backfill Construction In Orthogonal Underpass Section Of An Open-Cut Interchange Tunnel, Li Qingda, Li Dexing, Yu Tingshun, Han Xi, Liu Jiansong

Journal of China & Foreign Highway

This study investigated the mechanical effects of backfill construction in the orthogonal underpass section of a full-section complex open-cut interchange tunnel.The research was based on the small-clear-distance interchange tunnel project at the extension section of Jinzhou Avenue and Xingguang Avenue in Chongqing.A combined approach of numerical simulation and on-site in-situ test measurement was adopted to analyze the influence of different backfill materials,tunnel cross-section types,and complex construction procedures on the mechanical behavior of the underpass tunnel.The mechanical effects of backfill construction in the orthogonal underpass section were determined.The following findings are revealed:During the backfill construction process,the displacement and internal force of …

Research On Automatic Review Method Of Highway Bim Based On Knowledge Graph, Wang Wuyu, Shao Kebo, Zhang Feng

Journal of China & Foreign Highway

Building information modeling (BIM ),characterized by multi-dimensional modeling and multi-source data integration,is becoming a key technology to promote the innovation and digital transformation of the highway design industry.Taking BIM as the design deliverable is an inevitable trend in the future development of highway engineering design.However,the current highway BIM review is mainly conducted manually,which brings about problems such as low efficiency,susceptibility to errors,and high subjectivity.This makes it difficult to adapt to the review requirements of the three-dimensional (3D) digital design mode.To this end,this study proposed an automatic review method of highway BIM based on a knowledge graph.By constructing the knowledge graph …