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Articles 1441 - 1470 of 11750
Full-Text Articles in Entire DC Network
Water Inrush Mechanism And Water-Conducting Fractured Zone’ Developmental Patterns Of A Typical Ultra-Thick Coal Seam In The Huanglong Coalfield During Fully Mechanized Mining, Yan Heping, Li Wenping, Duan Zhonghui, Yang Yugui
Water Inrush Mechanism And Water-Conducting Fractured Zone’ Developmental Patterns Of A Typical Ultra-Thick Coal Seam In The Huanglong Coalfield During Fully Mechanized Mining, Yan Heping, Li Wenping, Duan Zhonghui, Yang Yugui
Coal Geology & Exploration
The mining of thick coal seams in the Huanglong Jurassic coalfield has led to the formation of high water-conducting fractured zones, which are prone to connect the extremely thick sandstone aquifers of the overlying Cretaceous Luohe Formation. Qinggangping Coal Mine in the coalfield exhibits the typical characteristics of pulsed water inrushes during coal mining, posing a severe threat to safe mining. This study investigated the fully mechanized mining face 42105 in Qinggangping Coal Mine. Using 3DEC discrete element simulation, flushing fluid leakage in boreholes, integrated geophysical exploration, and borehole TV, this study examined the developmental patterns of the water-conducting fractured …
Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment, Yang Wenjuan, Zhao Dian, Zhang Xuhui, Chen Xin, Zheng Xili, Liu Yanhui, Zhang Ran, Wan Jicheng
Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment, Yang Wenjuan, Zhao Dian, Zhang Xuhui, Chen Xin, Zheng Xili, Liu Yanhui, Zhang Ran, Wan Jicheng
Coal Geology & Exploration
The automation of excavating and anchoring operation is critical for intelligent excavation of coal mine roadway. Aiming at the challenges of relative pose measurement and collision detection during the alternating operation of the current excavating and anchoring equipment, a digital twin-driven tracking, positioning and collision detection method was proposed. Firstly, in order to overcome the influence of low illumination, high dust and complex background interference in the underground excavating face, the multi-point infrared LED target is taken as the information source, the infrared LED feature point image is collected by industrial camera, the center of the spot is extracted using …
Weight And Resistance Reduction Mechanism Of Drilling Rods For Drilling In Soft Coal Seam And Its Application, Wang Yonglong, Guo Jiakuan, Yu Zaijiang, Du Kang, Sun Yuning
Weight And Resistance Reduction Mechanism Of Drilling Rods For Drilling In Soft Coal Seam And Its Application, Wang Yonglong, Guo Jiakuan, Yu Zaijiang, Du Kang, Sun Yuning
Coal Geology & Exploration
Gas drainage boreholes during construction is a necessary means to control gas hazards. In response to the issues such as high drilling resistance, low drilling efficiency, and high labor intensity caused by the significant self-weight of the drilling rod in drilling into the soft coal seams, a research approach of reducing the self-weight and lowering the drilling resistance by optimizing the drilling rod structure was proposed. Thus, a four-winged concave grooved drilling rod was designed to address both of its advancing resistance and rotating torque losses. Meanwhile, a drilling resistance model for the drilling rod was established. On this basis, …
Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning, Liu Changye, Yang Xianyu, Cai Jihua, Wang Ren, Wang Jianlong, Dai Fanfei, Guo Wanyang, Jiang Guoshe, Feng Yang
Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning, Liu Changye, Yang Xianyu, Cai Jihua, Wang Ren, Wang Jianlong, Dai Fanfei, Guo Wanyang, Jiang Guoshe, Feng Yang
Coal Geology & Exploration
The rheology of drilling fluid, which characterizes its flow and deformation, is vital for transporting and suspending rock cuttings as well as for enhancing the drilling rate. Precise control of drilling fluid rheological parameters is essential to ensure borehole cleanliness and efficient drilling. This paper proposes an intelligent identification method for drilling fluid rheological parameters based on Convolutional Neural Networks (CNNs). The method employs magnetic stirring to generate stable images of drilling fluid flow, uses various data augmentation methods to increase the number of images and create a database, thereby enhancing the model’s robustness and generalization capabilities. The AlexNet CNN …
Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik
Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Engineering And Geological Zoning Of The Distribution Areas Of The Eocene Clays Of Northern Tamdytau, Mirabbas Mirsaatovich Zakirov, Inobat Abduvaxidovna Agzamova, Dilshod Kalandarovich Begimkulov, Golibjon Ernazar Ogli Ochilov, Temur Makhmarajabovich Khudoyberdiyev, Dastan Jamal Uli Madiyarov
Engineering And Geological Zoning Of The Distribution Areas Of The Eocene Clays Of Northern Tamdytau, Mirabbas Mirsaatovich Zakirov, Inobat Abduvaxidovna Agzamova, Dilshod Kalandarovich Begimkulov, Golibjon Ernazar Ogli Ochilov, Temur Makhmarajabovich Khudoyberdiyev, Dastan Jamal Uli Madiyarov
Technical science and innovation
The article discusses scientific research on the integrated assessment of the problem of ensuring the sustainability of buildings and structures for industrial and civil purposes. The relevance is due to the development of various zoning methods to establish territories with reliable results on the spread of special soils. Especially in cases where swelling clays are common in the territory, characterized by high sensitivity to weather and climatic conditions. Based on the above, the purpose of engineering and geological zoning of the areas of distribution of Eocene clays of Northern Tamdytau was to identify areas of new construction, to ensure the …
Burning Calories, Burning Ocean: Metabolic Rate In Bivalves As A Predictor Of Extinction Selectivity Through Time And During Rapid Global Warming, Siddharth Gavirneni
Burning Calories, Burning Ocean: Metabolic Rate In Bivalves As A Predictor Of Extinction Selectivity Through Time And During Rapid Global Warming, Siddharth Gavirneni
Theses - ALL
Organismal metabolic rate is linked to environmental temperature and oxygen consumption, and as such, may be a useful predictor of extinction risk during major climate- driven crises. However, metabolic attributes can be quantified in many ways, highlighting differing aspects of organisms’ ecology. Here, we estimate resting whole-body and mass-specific metabolic rates in post-Carboniferous bivalve taxa using body size and seawater paleotemperature to assess how metabolic rate determines survival both during and outside of intervals of rapid climate warming, or ‘hyperthermals’. Accounting for the effects of geographic range size, we find a pattern of preferential extinction of bivalves with lower total …
Online Temporal Data Mining And Learning: Pursuing Enhanced Efficiency And Robust Algorithms, Sheng Zhong
Online Temporal Data Mining And Learning: Pursuing Enhanced Efficiency And Robust Algorithms, Sheng Zhong
Computer Science ETDs
Time series data mining and learning serve as a cornerstone across various domains, including finance, healthcare, and science. Recent advancements in network and sensor technologies have ignited an increasing interest in real-time temporal data mining and learning techniques. Various tasks benefit from these techniques, such as environmental monitoring, event detection, anomaly identification, and forecasting. However, these techniques still face significant challenges in the online environment settings, encompassing aspects like efficiency, accuracy, robustness, and scarcity of labeled data. This dissertation presents four innovative solutions: FilCorr, DCT-MASS, FewSig, and BitLINK to overcome these challenges. We evaluate each method and showcase their practical …
Deformation Mapping And Modeling Of The Aleutian Volcanoes With Insar And Numerical Models, Jiahui Wang
Deformation Mapping And Modeling Of The Aleutian Volcanoes With Insar And Numerical Models, Jiahui Wang
Earth Sciences Theses and Dissertations
Surface deformation mapping is an essential component for comprehensive monitoring of volcanic activities, serving as a vital tool for discerning crucial insights into magma dynamics, storage, and migration for accurate hazard forecasting, assessment, and mitigation. However, monitoring of the volcanic deformation across the Aleutian volcanic arc is usually limited by the lack of terrestrial sensors deployed due to their remote locations and hostile environmental conditions, necessitating alternative methodologies for data acquisition and analysis.
My PhD study aims at precisely mapping the crustal deformation for the Aleutian volcanoes and tracking the evolution of the magmatic system with Interferometric Synthetic Aperture Radar …
The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright
The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright
Earth Sciences Theses and Dissertations
This thesis presents new data on the origin of the Western Iron Ore Group (W-IOG), a Paleoarchean succession deposited on sialic rocks of the Singhbhum Craton. U-Pb ages from zircons from a tuff overlying the Lower Shales just below a banded iron formation (BIF) pin the age of the section to 3.39 Ga. Unconformably overlying the whole IOG section is the Darjing Group, which contains the Birtola Sandstone (on the basis of this work, now estimated to be 2.35 Ga). The lack of penetrative deformation and low-grade metamorphism makes these rocks excellent subjects for combined radiogenic and stable isotope studies. …
Investigating The Effects Of Suspended Algal Content, Dissolved Oxygen, And Temperature On A High-Frequency Acoustic Attenuation System In A Controlled Laboratory Environment, Noah Watson
Honors Theses
The Single Frequency Acoustic Attenuation System (SFAAS) has been developed at the National Center for Physical Acoustics (NCPA). This system uses acoustic methods to monitor fine suspended sediment concentration in streams. Site-specific calibrations are necessary for this system, and previous research has indicated that algal concentration or dissolved oxygen concentration of water may affect collected data. Temperature, dissolved oxygen concentration, and fluorescence, used as a proxy for algal concentration, were monitored during this system’s use, and calibrations were derived to account for the effect of each of these variables on acoustic measurements. It has been shown that temperature has a …
Climate Change In Mississippi: A Journalistic Exploration Of Education And Activism, Kala Nance
Climate Change In Mississippi: A Journalistic Exploration Of Education And Activism, Kala Nance
Honors Theses
Climate Change in Mississippi: A Journalistic Exploration of Education and Activism takes an investigative, journalistic approach toward climate change in Mississippi. Specifically, how education and awareness have a direct impact on Mississippi industries, people and legislation. The project explored the level of acknowledgement of climate change across the state, and how certain individuals used advocacy to encourage education about climate change to raise awareness of the severity of the situation. This project includes interviews with university professors and researchers, non-profit organizations, educational groups and working individuals in some of Mississippi’s largest areas of employment. Additionally, this project draws on research …
Surface Water Quality Assessment Of Mingo Creek County Park: The Impacts Of Extractive Industries, Mikayla J. Bayto
Surface Water Quality Assessment Of Mingo Creek County Park: The Impacts Of Extractive Industries, Mikayla J. Bayto
Electronic Theses and Dissertations
Historical and current extraction operations and infrastructure, including natural gas pipelines, conventional and unconventional oil and natural gas drilling, longwall coal mining, and strip coal mining, occur throughout the Mingo Creek watershed of Washington County, Pennsylvania, including Mingo Creek County Park. Mingo Creek and several associated tributaries flow through Mingo Creek County Park, eventually discharging into the Monongahela River. An independent water quality study was conducted from June 2020 through July 2023 in Mingo Creek County Park to determine if historical and current extraction activities impact Mingo Creek and its associated tributaries. Weekly sampling of Mingo Creek and associated tributaries …
Evaluation Of Changes In Evaporative Losses From Lake Powell Reservoir Contributions In The Colorado River Basin, Maria Mlinarcik
Evaluation Of Changes In Evaporative Losses From Lake Powell Reservoir Contributions In The Colorado River Basin, Maria Mlinarcik
Electronic Theses and Dissertations
The Colorado River Basin (CRB) is one of the most critical water sources for the western United States (U.S.) and Mexico. For over a century, numerous policies and regulations have been implemented in attempts to manage the Colorado River Basin to address the concern of overuse, collectively referred to as the “Law of the River.” The USGS hydrologist E.C. LaRue warned that the optimistic estimates used in negotiating the Colorado River Compact did not align with the actual water availability in the river. His analysis in 1925 revealed a potential deficit if all allocated water was utilized, exacerbated by overallocation …
The Use Of Repurposed Whole Textiles To Modify The Mechanical And Hydrogeological Properties Of Green Roof Media And Granular Soils, Angelis Almanzar-Chevalie, Yehya Elfgeeh, Calvin O. Walters Jr.
The Use Of Repurposed Whole Textiles To Modify The Mechanical And Hydrogeological Properties Of Green Roof Media And Granular Soils, Angelis Almanzar-Chevalie, Yehya Elfgeeh, Calvin O. Walters Jr.
Publications and Research
This study investigates using repurposed whole textiles to modify the mechanical and hydrogeological properties of lightweight Green Roof media and granular pavement soils.
Green Roof Media Green roofs aim to bring the advantages of suburban agriculture to urban environments while improving energy efficiency and enhancing stormwater management in public, commercial, and residential buildings. Previous studies by City Tech undergraduate research assistants demonstrated significant modification in hydrogeological properties when incorporating textile fabric up to 3% textile by weight (%Tex) at an aspect ratio of 1:1. The effects of mixing repurposed whole textile fiber with Green Roof media is evaluated with regards …
The Influence Of Soil Composition On Stormwater Retention And Runoff In Green Roofs At Portland State, Manuel Edrozo, Lily Green, Mitchell Mcdonald, Nicholas Olmos
The Influence Of Soil Composition On Stormwater Retention And Runoff In Green Roofs At Portland State, Manuel Edrozo, Lily Green, Mitchell Mcdonald, Nicholas Olmos
Student Research Symposium
The purpose of this study is to determine what soil composition is best for green roofs at Portland State; we aim to compare the current soil to the original substrate, to measure which composition retains the most water, and which filters out the most pollutants in stormwater runoff. Five different soil compositions were tested — original, current, layered mixed, solid mixed, and potting soils — and 1,000mL of high and low intensity rainfall (in/hr) was simulated for each of the mixtures. Water was allowed to filter through the soils for a predetermined time (10min for a high application rate and …
Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck
Textural Investigation Into Rapid Welding Transitions In The Tuff Of Leslie Gulch Along Succor Creek At The Mahogany Mountain-Three Fingers Rhyolite Field, Southeastern Oregon, Alicia J. Martinez-Garling, Martin J. Streck
Student Research Symposium
The Mahogany Mountain-Three Fingers Rhyolite Field (MM-TFrf) in southeastern Oregon, associated with mid-Miocene rhyolite activity and Columbia River flood basalts, has been the subject of geological scrutiny. Previous studies proposed separate origins for the tuff of Leslie Gulch (LGT) and Spring Creek, but Benson and Mahood (2006) suggested a single ignimbrite event at 15.8 Ma, prompting a reassessment of MM-TFrf's history. This research focuses on LGT, investigating textural disparities between welded and non-welded tuff formations. Petrographic examinations delve into the transformation stages of pyroclastic tuff deposition, revealing the dynamic influences of volcanological and magmatic processes on welded and non-welded tuff …
Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan
Analyzing Intensifying Storm Events Correlation To Landslide Frequency In Portland’S West Hills, Aurora Villa Juan
Student Research Symposium
As the Pacific Northwest climate changes, extreme weather, such as intensifying storms, and a shift in the type of precipitation experienced with warmer winters causing more precipitation to fall as rain instead of snow, may lead to an increased frequency of landslides. There have been several recent landslides in Portland, noticeable to the public, particularly in areas of high elevation such as Council Crest, which stands at 1,073 feet. Additionally, residents of neighboring homes have observed changes in the landscape, including those on private properties. To better safeguard both public and private property, comprehensive research and mitigation efforts are required. …
Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry
Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry
School of Earth & Environment Departmental Research
Previous studies on microtaphonomy have identified multiple types of organic microstructures in fossil vertebrates from a variety of time periods and past environmental settings. This study investigates potential taphonomic, paleoenvironmental, and paleoclimatic controls on soft tissue and cellular preservation in fossil bone. To this end, fifteen vertebrate fossils were studied: eight fossils collected from the Oligocene Sharps Formation of the Arikaree Group in Badlands National Park, South Dakota, and seven fossils from formations in the underlying White River Group, including the Oligocene Brule Formation of Badlands National Park, and the Eocene Chadron Formation of Flagstaff Rim, Wyoming; Toadstool Geologic Park, …
Reactivity Of Adsorbed Trace Metals At Metal (Oxyhydr)Oxide Surfaces As Probed With Isotope Exchange, Greg Ledingham
Reactivity Of Adsorbed Trace Metals At Metal (Oxyhydr)Oxide Surfaces As Probed With Isotope Exchange, Greg Ledingham
Arts & Sciences Graduate Student Theses and Dissertations
Metal (oxyhydr)oxide surfaces regulate the accessibility of trace metals in soils and aquatic systems. Up to half of the trace metals in urban environments, river systems, and contaminated soils are associated with mineral surfaces yet this pool often remains bioaccessible. Past studies of adsorption-desorption suggest that macroscopic rates of adsorption at mineral surfaces are likely mass transfer-limited and show biphasic rates, with a fast-adsorbing fraction equilibrating in seconds to minutes and a slower-adsorbing pool binding over a timescale of hours to days. In addition, adsorption-desorption hysteresis has been observed for some metals after aging at metal (oxyhydr)oxide surfaces, indicating that …
Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys
Characterizing The Engineering Properties Of Three Lithologies From Montana And Idaho Using Acoustic Emissions And Stress-Strain Measurements, Mary Humphreys
Graduate Theses & Non-Theses
In this study, stress and strain measurements from unconfined compression tests were used to determine the peak stress, yield stress, Young’s modulus, and Poisson’s ratio of 20 specimens representing three lithologies (sandstone, norite, and argillite-quartzite mix) from Idaho and Montana. Along with traditional strength and deformation parameters, crack initiation (CI) and crack damage (CD) values were also interpreted, corresponding to the stress levels associated with the formation and coalescence of microcracks as a specimen is exposed to increasing stress levels. Acoustic emissions (AE) data were collected along with traditional stress-strain data as this has become a popular method for interpreting …
Glacier Lake Inventory And Lake Outburst Flood Hazard Assessment In Kanchenjunga Conservation Area, Nepal, Prabish Khadka Chhetri
Glacier Lake Inventory And Lake Outburst Flood Hazard Assessment In Kanchenjunga Conservation Area, Nepal, Prabish Khadka Chhetri
Theses
This study presents a comprehensive assessment of glacial lakes and land surface temperature (LST) dynamics within the Kanchenjunga Conservation Area (KCA) from 2010 to 2023. The KCA holds significant ecological importance, serving as a critical habitat for diverse flora and fauna, while also playing a vital role in regional hydrological systems. Additionally, its stunning landscapes attract tourists and mountaineers from around the world, further emphasizing the need for understanding environmental changes within the area. Utilizing medium to high-resolution satellite imagery from PlanetScope for glacial mapping and Landsat for LST analysis, the research aimed to achieve two primary objectives: creating an …
Machine Learning And Geostatistical Approaches For Discovery Of Weather And Climate Events Related To El Niño Phenomena, Sachi Perera
Machine Learning And Geostatistical Approaches For Discovery Of Weather And Climate Events Related To El Niño Phenomena, Sachi Perera
Computational and Data Sciences (PhD) Dissertations
El Nino and La Nina are worldwide environmental phenomena brought about by repetitive changes in the water temperature of the Pacific Ocean. Even though the El-Nino impact focuses on a smaller area in the Pacific Ocean near the Equator, these developments have global repercussions, where temperature and precipitation are influenced across the globe, causing droughts and floods simultaneously. In this dissertation, we first derived a drought vulnerability index for the Nile basin, identifying regions with high and low drought risk under ENSO conditions. Next, we evaluated the coherence and periodicity of the ENSO signal to detect its implications on MENA …
The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield
The Olmsted Fault, Southernmost Illinois: A Key To Understanding Seismic Hazard In The Northern New Madrid Seismic Zone, Christopher E. Bexfield
Theses and Dissertations
The northernmost extent of the New Madrid seismic zone in the central USA has been investigated using an integrated approach involving both compressional-wave (P) and horizontally polarized-wave (SH) seismic reflection and regional and dedicated borehole geophysical information in order to assess seismic hazard and risk. Our study area, centered around southernmost Illinois and western Kentucky, USA, represents an area of concentrated facilities (e.g., lock and dam sites and chemical plants on the Ohio River near its confluence with the Mississippi River) as well as an area of high potential soil amplification due to earthquake shaking. Integrated high-resolution seismic reflection profiles …
Free And Forced Vibrations Of Elastically Restrained Cantilever With Lumped Oscillator, Alireza Babaei, Johné Parker, Paria Moshaver
Free And Forced Vibrations Of Elastically Restrained Cantilever With Lumped Oscillator, Alireza Babaei, Johné Parker, Paria Moshaver
Earth and Environmental Sciences Faculty Publications
The efficiency assessment of cantilever-based energy harvesters relies on vibrational analysis, which necessitates modi- fications aimed at enhancing efficiency. These modifications involve manipulating the fundamental frequency to lower values and encompassing a wider range of resonances within a specified bandwidth. Consequently, this paper introduces an original analytical-numerical exploration into the vibratory response of a cantilever with a novel boundary condi- tion involving an elastically restrained oscillator-spring arrangement. At the microbeam’s tip, an oscillator is elastically confined by a linear spring, resulting in a novel set of coupled governing equations and a distinct shearing boundary condition. Microbeam equations is derived from …
A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris Mccaslin, T. Dylan Mikesell, Hans-Peter Marshall
A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris Mccaslin, T. Dylan Mikesell, Hans-Peter Marshall
Geosciences Faculty Publications and Presentations
Accurate knowledge of snow mechanical properties, including Young's modulus, shear modulus, Poisson's ratio, and density, is critical to many areas of snow science and to snow-related engineering problems. To facilitate the assessment of these properties, an innovative non-contacting laser ultrasound system (LUS) has been developed. This system acquires ultrasound waveform data at frequencies ranging from tens to hundreds of kHz in a controlled cold-lab environment. Two different LUS devices were compared in this study to determine which recorded more robust ultrasound in granular ice mix samples. We validated the ultrasound observations with poro-elastic traveltime modeling based on physical and empirical …
Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue
Building And Using A Hydrology Experiment For Place-Based Learning With Native American Students, Michaela Shallue
All Graduate Theses and Dissertations, Fall 2023 to Present
Geoscience has a known diversity problem, specifically a participation gap of ethnic minority representation, and it is especially severe regarding Native American representation. To address this participation gap, an identity gap needs to be addressed first. Native students need to visualize themselves as geoscientists before they can commit to geoscience programs and careers. This project uses a hands-on, place-based learning activity as an opportunity for Native students to better see themselves as geoscientists.
A portable rainfall simulator was constructed, calibrated, and refined for use in teaching concepts about rainfall, runoff, and erosion. It was employed in place-based learning exercises with …
The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba
The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba
Undergraduate Theses
An agricultural system where solar energy generation and agricultural systems are used together for mutual benefit, agrivoltaics reduces loss of water due to evaporation, particularly in drylands. Central California has faced extreme droughts, and water has become a scarce resource. However, the wide-scale use of agrivoltaics has been limited due to lack of knowledge about agrivoltaics and also the lack of funding for start-up agrivoltaics projects. Therefore, this research investigated the potential for agrivoltaics in Central California to reduce irrigation water consumption using a review of multiple crop studies using agrivoltaics to determine an optimal crop for agrivoltaics and a …
Public Horticulture: Process And Design Of The Lincoln Botanical Garden, Brad Kindler
Public Horticulture: Process And Design Of The Lincoln Botanical Garden, Brad Kindler
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Beginning in 2012, the local non-profit, The Lincoln Botanical Garden, began organizing the conceptual design and creation of a glass conservatory within a botanical garden in Lincoln, Nebraska. These proposed urban enhancements seek to fill a gap in garden amenities in the city by providing year-round access to public horticulture programming and education.
This project, Public Horticulture: Process and Design of the Lincoln Botanical Garden, documents these efforts and makes design recommendations for a themed Glacial Erratic Garden that could be constructed within the botanical garden.
Advisors: Ellen Paparozzi and Sam Wortman
Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize–Soybean Rotation In Nebraska, Tanessa Morris
Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize–Soybean Rotation In Nebraska, Tanessa Morris
School of Natural Resources: Dissertations, Theses, and Student Research
The precise measurement of soil water content (SWC) is crucial for effective water resource management. This study utilizes the Cosmic Ray Neutron Sensor (CRNS) for area-averaged SWC measurements, emphasizing the need to consider all hydrogen sources, including the time-variable ones like plant biomass and water content. Chapter 1 presents a background on soil moisture estimation, CRNS technology, and an overview of the study. It discusses various soil moisture measurement techniques, highlights the gap in knowledge addressed by CRNS technology, explains CRNS functionality and advancements, and outlines the study's motivations and methods.
Chapter 2 reports a study conducted near Mead, Nebraska, …