Digital Commons Network^™

An Image Recognition And Multi-Parameter Quantitative Characterization System For Fractures In Roadway Rocks, Xiong Yu, Jiang Lichun, Kong Dezhong, Li Jinzhu

Coal Geology & Exploration

Objective Conventional measurement methods for rock fractures suffer from low efficiency and high subjectivity. On the other hand, simple image recognition techniques struggle to achieve high-precision multi-parameter integrated analysis of rock fractures in complex roadway environments. To address these challenges, this study aims to develop an image recognition and multi-parameter quantitative characterization system for rock fractures. Methods At the core of the system is the formulation of a combined image preprocessing strategy. Specifically, fracture segmentation is conducted based on adaptive threshold binarization, isolated noise points are removed using morphological opening, and median filtering is introduced to perform the refined polishing …

A Method Of Reflected In-Seam Wave Imaging Based On The Structural Similarity Index Of Adjacent Gathers, Wang Ji, Wei Zhongli, Ye Hongxing, Wu Guoqing, Liu Shuo, Niu Huan, Su Xiaoyun

Coal Geology & Exploration

Background Reflected in-seam wave detection represents a major method for exploring geological anomalies in underground coal mines. This method is well suited to detecting concealed structures (e.g., faults and collapse columns) within coal seams in the tunneling direction of roadways or along their side walls. In recent years, to meet the safety requirements of green mine construction, explosive sources have been substituted with mechanical hammer impacts in increasing reflected in-seam wave detection. However, compared to conventional explosive sources, hammer impacts exhibit significantly lower instantaneous energy intensity and consistency. These limitations lead to reduced quality of reflected in-seam wave imaging, thus …

A Seismic Prediction Technology For Coalbed Methane Sweet Spots And Its Engineering Application In The Ordos Basin, Zhang Mengbo, Li Fei, Zhang Dong, Peng Jiankang, Cui Xiaojie, Ni Na, Long Shengfang, Tao Yu, Zhu Jun

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) reservoirs tend to exhibit significant tuning effects of thin interbeds, leading to challenging localization of actual coal seam boundaries, limited identification accuracy of micro-amplitude structures in the coal seam roof, and poor stability of the seismic responses of the reservoirs' gas-bearing properties. To address these challenges, this study investigated the No. 8 coal seam of the Benxi Formation in the Mizhi area, Ordos Basin. Accordingly, a method with the prediction of gas-bearing properties as the primary controlling factor was developed for the seismic prediction and comprehensive evaluation of CBM sweet spots. Methods First, the actual …

Assessment Of The Radionuclide Concentration Levels Of Water And Sediments Along The Mara River, Gasper Kachenge, Abubakary Salama, Abdalah Kileo, Furaha Chuma

Tanzania Journal of Science

For many years, several factors have impacted the water quality of the Mara River, including population growth, agricultural expansion, livestock keeping, mining, and industrial activities. These factors have intensified water pollution and climate change effects around the river. While previous studies have mainly focused on assessing heavy metal pollution risks on the Mara River, this study evaluates the concentration levels of radionuclides in boreholes, water, and sediments along the river and its tributaries. Naturally occurring radioactive materials, including 226Ra, ²³²Th, and ⁴⁰K, were evaluated. A high-purity germanium radiation detector (HPGe) with a coaxial detector system coupled with Gamma Vision software …

The Effectiveness Of Bacillus-Coated Npk Fertilizer On Broccoli Growth, Nutrient Status, Rhizosphere Bacillus Population, Yield, And Flower Quality, Betty Natalie Fitriatin, Rara Rahmatika Risanti, Reginawanti Hindersah, Fasa Aditya Hanindipto, Gita Bina Nugraha

Jurnal Kultivasi

Efforts to increase the availability of macronutrients in soil have relied on inorganic fertilization, particularly NPK fertilizers. However, global challenges in the fertilizer raw material supply chain, including price fluctuations and availability, are driving the need for more efficient and sustainable fertilizer alternatives. The field experiment was conducted in Baruajak, Lembang District, West Java, Indonesia, to evaluate the effectiveness of Bacillus-coated NPK fertilizer on broccoli (Brassica oleracea var. italica) growth, nutrient status, rhizosphere Bacillus population, yield, and flower quality. The experiment used a randomized complete block design with 15 fertilizer treatments and three replications. Treatments consisted of two coated NPK …

Effects Of Ab Mix Hydroponic Solution And Ameliorant Mixtures On Cayenne Pepper Growth And Yield In An Inceptisols, Tien Turmuktini, Betty Natalie Fitriatin, Tualar Simarmata, Firda Widayanti, Nuryanti, Lia Amalia, Elly Roosma Ria, Linlin Parlinah

Jurnal Kultivasi

Cayenne pepper (Capsicum frustescens L.) cultivation faces several problems, including acidic pH and inadequate nutrient management. These problems can be addressed by using a mixture of various ameliorants and AB mix nutrient solutions. This study aimed to determine the effect of ameliorant mixture dosage and AB mix solution concentration on soil chemical properties, growth, and yield of cayenne pepper. The experiment used a randomized block design, consisting of two factors: nutrient solution concentration and ameliorant dosage. The factor of nutrient solution concentration consisted of four levels, i.e., 700, 1000, 1300, and 1600 ppm, while the factor of ameliorant dosage also …

Earthquake-Resistant Design And Base Isolation Techniques, Christian George, Jacob Sweeten, Gabriela Cotto, Savion Stewart

Discovery Day - Daytona Beach

Earthquake-resistant design has become a critical feature in construction near active fault lines, where seismic activity is most frequent and potentially destructive. In recent years, technological advancements have significantly improved methods for protecting buildings from earthquake damage. Among these innovations, base isolation systems have appeared as one of the most effective solutions. By decoupling a building from ground motion, base isolators reduce the transmission of seismic forces, helping to prevent structural damage and support building stability during earthquakes. In addition to improving safety, base isolation systems can also reduce long-term costs associated with earthquake-related repairs and maintenance. Base-isolated structures are …

System And Method For Detecting Subsurface Voids Using Controlled Heat Addition, Chase Nilsson

Discovery Day - Daytona Beach

This study evaluates controlled heat addition in a confined space to estimate enclosed volumes for irregularly shaped spaces. The intent is to detect hidden voids in cave environments. Conventional methods for identifying such voids are often costly, logistically difficult, and limited in accuracy. Preliminary experiments were conducted with a controlled heat source, a temporary thermal barrier to isolate the test chamber, and simple temperature sensors. Temperatures were recorded for the pre-test baseline, the heating interval, followed by a cooling period. The thermal response showed clear engineering trends that warrant further exploration and modeling. Preliminary results indicate that transient temperature changes …

Temperature And Hydrologic Context Influence Methane Variability In A Low-Salinity Marsh, Zoie Brauser

Dissertations and Theses

Coastal wetlands are biogeochemical hotspots that capture and transform carbon and nutrients. Wetland restoration is increasingly used as a climate mitigation strategy because of wetlands' capacity to sequester large amounts of carbon. However, low-salinity tidal marshes exhibit high variability in methane (CH₄) emissions, which could partially offset carbon sequestration under certain conditions. Understanding the drivers of CH₄ variability is crucial for restoration and conservation work. This project uses an observational research approach to assess the relationships between environmental factors and carbon dioxide (CO₂) and CH₄ soil gas fluxes in a restored low-salinity tidal marsh …

Understanding The Long-Term Patterns Of Change Of A Tidal Marsh In Mission Bay, San Diego, California, Carrie A. Shuster, Theresa Sinicrope Talley Ph.D., Drew Talley Ph.D., Zhi-Yong Yin Ph.D., Kellie Uyeda Ph.D.

Theses

Coastal marshes are among California’s most productive ecosystems and the most impacted, having been extensively modified by dredging, filling, and urban development. This thesis investigates over a century of change for a marsh in Northern Mission Bay, San Diego, California using ecological and spatial analyses.

Chapter 1 provides an overview of the environmental history and current land use of the Northern Mission Bay marsh, tracing changes from pre-contact Indigenous stewardship through colonial and modern urban development. It also introduces a restoration plant palette derived from historical and contemporary species occurrences, ecological functions, and documented cultural uses. By integrating ethnobotanical knowledge …

Spatiotemporal Analyses Of The Biological Condition Gradient (Bcg) For Florida’S Coral Reef, Maya Becker

All HCAS Student Capstones, Theses, and Dissertations

A conceptual model known as the Biological Condition Gradient (BCG) was originally constructed for biological assessments and has recently been adopted for use on Florida’s coral reef after repeated anthropogenic stressors have been linked to declines within the state of the reef. Anthropogenic pressures have reduced water quality, exacerbating coral disease and associated mortality disrupting ecosystem services and biological function throughout Florida’s coral reefs (FCR). The intention of the BCG model is to assess biological condition against increasing levels of anthropogenic stress and to identify biological attributes and measurable increments of change from long term monitoring data. Differences in spatial …

Process From Noise: Erosion Threshold Variability And The Morphology Of Gravel-Bed Rivers, Robert Paul Kostynick

Arts & Sciences Graduate Student Theses and Dissertations

Rivers are remarkably consistent as their geometry, width, depth, and slope change systematically downstream in response to differences in fluid discharge and sediment transport throughout a channel. Rivers move both water and sediment through terrains that depend on these downstream geometric adjustments influencing water quality, ecology, infrastructure, channel morphology, and landscape evolution at increasing timescales respectively. Rivers thus influence all aspects of life and define our spatial landscapes that shape boundaries, whether physical, politically, or socially. Nevertheless, a river is dynamic and does not adhere to human-defined boundaries, making it vital that we understand how these features change over time …

Wavelet-Based Multiscale Analysis Of Cave Co₂ Concentration In Response To Short-Term High-Intensity Tourism Activities: Spatiotemporal Heterogeneity And Lag Characteristics, Mingda Cao, Wenwen Song, Yan Zhang, Jie Zhang, Zhiqiang Yao

International Journal of Speleology

High-intensity tourism activities can cause a significant increase in cave air CO₂ concentration, thereby affecting the cave micro-environment and secondary carbonate deposition. During the 2023 National Day Golden Week, high-frequency continuous monitoring of cave air CO₂ partial pressure (PCO_2(A)) and visitor numbers was conducted in Dawang Cave, Anhui Province. Wavelet transform and cross-correlation analyses were used to reveal the multi-scale response characteristics of CO₂ concentration to tourism activities. The results show that: (1) PCO_2(A) exhibited clear diurnal variations (higher during the day, lower at night) and decreased spatially with enhanced ventilation, controlled jointly by …

Mono Gold: An Informal Account Of The Geology, Production, And History Of Mono County Gold And Silver Mining Districts, D. D. Trent

Eastern Sierra History Journal

Mono Gold explores the mining production, technology, and history of the Eastern Sierra, with a special focus on Mono County. Author Dee Trent, a geologist, spent decades visiting, researching, and photographing each of the mining operations discussed in this book-length monograph.

Alaska Earthquake Center Quarterly Review October-December 2025, Heather Mcfarland, Beth Grassi, Austin Holland, Nate Murphy, Elisabeth Nadin, Carolyn Parcheta, Michael West

Alaska Earthquake Center Reports

This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, fieldwork, our online presence, public outreach, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report.

Greenhouse Gas Flux Response In Biochar- And Compost-Amended Lawn Soils Under Simulated Water Saturation Conditions, Angel Salinas, Chu-Lin Cheng, Engil Pereira, Rafael M. Almeida, James Jihoon Kang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Understanding greenhouse gas emission dynamics in lawn soils is important for improving climate change mitigation strategies in urban and suburban landscapes. In this greenhouse mesocosm study, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes were measured from 12 turfgrass soil columns arranged in an unreplicated, completely randomized 4 × 3 factorial design. Four amendment treatments (biochar, compost, bio-com [1:1 volume ratio of biochar and compost], and unamended control) were combined with three water-table conditions (full saturation, half saturation, and unsaturated), with a single column representing each treatment combination. Columns were irrigated at 1 cm day−1 for 24 days, …

Forest Cover Effects On Canopy Interception Loss, Evapotranspiration, And Soil Infiltration On Stormwater Detention Basins, Alexandria N. C. Perez

Electronic Theses and Dissertations

Developing cities and increased impervious surfaces has resulted in more surface runoff and severe flooding. Harris County, Texas has experienced major flooding events, such as Hurricane Harvey in 2017 which was estimated to be a 9,000-year flood event. The Harris County Flood Control District (HCFCD) is dedicated to creating, maintaining, and finding new ways to reduce flooding damage such as the use of detention basins as green infrastructure. These basins are either populated by grass or are planted with various tree species. This study will identify the planted trees’ canopy interception loss, reference evapotranspiration, and enhanced soil infiltration effects within …

Characterizing Microplastics In Flood Sediments After Hurricane Helene In Asheville, North Carolina, Abigail Sgan

All Theses

Microplastics are contaminants of emerging concern whose ubiquity across natural environments results in their involvement in many kinds of natural processes, including transportation and deposition in natural systems. The purpose of this thesis is to characterize microplastics and determine the mechanisms that affect their distribution, transport, and sequestration within known Hurricane Helene flood deposits in fluvial and Southern Appalachian wetland environments after Hurricane Helene in Asheville, North Carolina. Four fluvial and four Southern Appalachian wetland environments were sampled after Hurricane Helene. Samples collected in fluvial environments were taken as grab samples from surficial sandy flood deposits left behind by flooding …

Evaluation Of High Temperature Thermal Energy Storage At A Field Site, Samuel R. Jennings

All Theses

A pilot-scale high-temperature thermal energy storage site has been developed at Clemson University and began operation in April 2025. High-temperature heat transfer fluid is circulated through a hexagonal array of borehole heat exchangers, which are installed up to 35 ft deep in the subsurface. The thermal energy is stored in the ground and is extracted by circulating the heat transfer fluid at a lower temperature. This test was expected to last more than six months and there was no way to evaluate the temperature data being measured. Since only temperature was being monitored, it was difficult to predict when key …

Implementation Of A Practical Sharp Interface Saltwater Intrusion Model To Assess Future Sea-Level Impacts, Alexandra G. Defalco

All Theses

Rising sea levels caused by global warming exacerbate saltwater intrusion, the inland movement of seawater into coastal aquifers. These processes increase susceptibility to freshwater contamination, surface flooding, and infrastructure damage. Numerical models are utilized to assess hazards to coastal aquifers on a regional scale.

The U.S. Navy is currently developing a robust, reduced-order groundwater modeling platform, SWI6, that uses the sharp interface approach to approximate the location of the freshwater-saltwater interface to define the extent of saltwater intrusion within an aquifer. Featuring compatibility with MODFLOW 6 unstructured grid formats and the Newton-Raphson formulation for better solution stability, SWI6 improves upon …

New Procedures Of Preserving Beet Tops, Hedvika Maskova, Jiri Havelik

IGC Proceedings (1977-2023)

The possibility was tested of preserving chopped (homogenized) beet tops in experimental tower silos. The treatments without preservatives were compared with treatments using pro­pionic acid (0.5 %) and allylisothiocyanate (1: 10,000). Silage quality, dry matter losses, and secondary fermentation 24, 72, 168, and 240 hours after unloading were determined. Chopping of beet tops was found to have a positive effect on the utilization of the silo volume and on the mechanization of silage handling, and to avoid the need of supple­mental compaction. Allylisothiocyanate and propionic acid had a favourable effect on the preservation process and helped to cut losses caused …

Environmental Dna For Endangered Freshwater Mussel Monitoring: A Review On Global Synthesis Of Edna Methods, Challenges, And Innovative Strategies, Mizanur Rahman, Md. Saydur Rahman, Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Freshwater mussels (family Unionidae) are among the most endangered aquatic species worldwide, making effective monitoring vital for their conservation. Traditional surveys are laborious, time-consuming, and often miss rare or low-density populations. Environmental DNA (eDNA) is a highly sensitive, non-invasive approach for freshwater mussel detection and monitoring; however, uncertainties in ecological interpretation continue to limit its broader application in freshwater biodiversity monitoring. We conducted a systematic review of 49 peer-reviewed studies, identified through an extensive literature search, to assess temporal research trends, methodological advancements, ecological contexts, and regulatory readiness of freshwater mussel eDNA monitoring. Findings show that freshwater mussel eDNA research …

Reading The Martian Surface: Impact Crater Distributions And Geochemical Signatures In Gale Crater As Recorded By The Curiosity Rover, Megan E. Hoffman

Earth and Planetary Sciences ETDs

The Curiosity rover has been exploring Gale crater, a large impact basin near the Mars equator since 2012. This mission has greatly improved our ability to explore the surface of Mars with a suite of geologic tools and cameras and has revealed that Mars likely once resembled present-day Earth. In this dissertation, I utilize measurements and data taken by Curiosity to analyze the distribution and preservation of small impact craters at meter scales, I quantify the formation characteristics of a small impact crater cluster, and I examine the presence of barium in a geologic unit with high-Si to constrain sediment …

Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby

Civil Engineering ETDs

Wildfires alter the water quantity and quality in downstream river networks. Fires promote biodiversity, maintain habitat, and provide many ecosystem services in a fire-adapted landscape. However, changes in the natural fire regimes can alter ecosystem function and threaten the water security of impacted downstream communities. The magnitude, timing, and persistence of these impacts are difficult to predict due to the lack of high-resolution datasets with adequate coverage to evaluate spatiotemporal trends after a fire. This dissertation moves us beyond the status quo to evaluate post-fire fluvial responses across scales, from the event-scale impacts after the Hermit’s Peak-Calf Canyon wildfire in …

History, Current Status, And Implications Of The Exploration And Exploitation Of Coal Resources In Guangxi, China, Wang Hui, Han Xiaozhong, Peng Zhilong, Li Huoying, Qin Baojian, Lu Ankang, Qin Xiaoyan, Peng Feifei, Xu Huiheng, Lan Bingui

Coal Geology & Exploration

Objective Based on a comprehensive review of the history and current status of coal exploration and exploitation, this study presents an analysis of both the endowment characteristics and the exploration and research levels of coal resources in Guangxi Zhuang Autonomous Region. From the perspective of coal self-sufficiency capacity and energy security guarantee, this study proposes several recommendations for the exploration and exploitation of coal resources in the region. Methods The exploration level, current status of exploitation, and supply-demand imbalance of coal resources in Guangxi are determined through a systematic literature review, surveys of coal mine enterprises, and exchanges with relevant …

Research And Practice Of Four-Dimensional In-Situ Stress Fields For Deep Coalbed Methane Production: A Case Study Of The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Chen Yiyu, Gao Deli, Zhao Haifeng, Chen Gaojie

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs are characterized by well-developed microstructures and natural fractures, along with highly heterogeneous rock mechanical properties and in-situ stress field distribution. The CBM production of the reservoirs tends to cause constantly evolving formation pressure and in-situ stress within the control ranges of CBM wells, further enhancing the complexity of stress distribution. Additionally, severe fracturing channeling can be observed between new and old wells. This phenomenon is primarily triggered by in-situ stress variations induced by large-scale fracturing and CBM production. Therefore, accurately assessing the dynamic evolutionary patterns of in-situ stresses in reservoirs after fracturing and during …

Enrichment Mechanisms Of U And Th Elements In The Bauxite Rock Series Of The Benxi Formation, Lower Carboniferous, Central North China Block, Bian Yukang, Zhang Xiaoyang, Chen Jinfeng, Lyu Dawei, Zhu Dongya, Liu Quanyou, Meng Qingqiang, Shen Xiaoli, Li Qing, Kong Weijiang, Dou Yunfei

Coal Geology & Exploration

Objective Uranium (U) and thorium (Th) in rocks and minerals are the material basis for the generation and release of crust-derived helium. Methods The enrichment characteristics and mechanisms of U and Th are key to understanding the accumulation of crust-derived helium reservoirs. Taking the bauxite series of the Benxi Formation in the central North China Block as the research object, this study reveals the enrichment mechanisms of U and Th in the bauxite series and calculates the helium generation rate by means of petrogeochemical and chronological research methods, combined with detrital zircon dating, sedimentary environment identification, and mass balance calculation. …

Sand Tank Experiments On The Seepage And Water Pressure Distribution During Single-Well Dewatering At The Bottom Of A Confined Aquifer, Wang Wenxue, Zhang Mengying, Li Yang, Fang Yuan, Zhao Shuli, Shen Mengjun

Coal Geology & Exploration

Background Depressurization through dewatering using inclined wells arranged at the aquifer bottom represents a crucial technical approach to the prevention and control of water-sand inrush disasters during coal mining beneath aquifers. However, the mechanisms underlying seepage-pressure interactions and water-preserved depressurization remain poorly understood. Methods Based on the water-yield properties of confined aquifers and the distribution characteristics of inclined wells for dewatering, this study developed a fan-shaped sand tank experimental system for simulating dewatering and seepage from confined aquifers. Using the experimental system, this study carried out seepage experiments using a partially penetrating well at the bottom of a confined aquifer …

Load Sharing Patterns And Their Key Influencing Factors For The Composite Structure Of A Lined Hard Rock Cavern For Compressed Air Energy Storage, Hu Lihua, Zhou Qiming, Zhang Kai, Yu Liyuan, Liang Xin, Sun Qiang, Wu Yun, Hu Chengguo, Li Wei

Coal Geology & Exploration

Objective Compressed air energy storage (CAES) in a lined hard rock cavern holds great prospects. However, the load sharing mechanisms of the cavern’s composite structure, comprising a sealing layer, lining, and surrounding rocks, remain poorly understood.Methods Based on the elastic analytical solutions of stress fields, this first study derived the radial load equilibrium equations for the composite structure of a lined hard rock cavern for CAES. Accordingly, a novel method for calculating the load sharing ratios of the composite structure was developed. Then, an analysis scheme for the load sharing ratios was designed. Using this scheme, this study investigated …

Cnn-Based Assessment Of The Degrees Of Fracture Development In Bedrocks And Classification Of Bedrock Weathering Zones, Lei Jian, Lu Haifeng, Fan Yufei

Coal Geology & Exploration

Background Bedrock weathering zones exhibit distinct vertical gradational characteristics. Accurately identifying the degrees of fracture development in the zones is critical to the safe production of mines in shallowly buried coal seams covered by thick water-bearing unconsolidated layers. Methods Focusing on the Qinan coal mine in Anhui Province, this study proposed a hybrid convolutional neural network (CNN) model, which enabled feature extraction using a synergistic architecture consisting of conventional convolutional layers and inception modules. Specifically, based on conventional log data and calculated shale content and fracture development index, combined with core observations, this study constructed a dataset containing labels that …