Digital Commons Network^™

A Machine Learning-Assisted Steering And Scheduling Framework For Big-Data Scientific Workflows On Heterogeneous Computing Platforms, Yijie Zhang

Dissertations

In next-generation scientific applications, the exponential growth of big data necessitates advanced techniques for efficient data storage, processing, and analysis. This has led to the construction of intricate computing workflows, managed and orchestrated by powerful engines in big data systems as exemplified by Hadoop. As scientific applications increasingly shift towards simulation-centric approaches, traditional methodologies face new challenges in accommodating the complexity of extreme-scale numerical modeling with numerous tunable parameters. To address these challenges, this dissertation propose to develop a machine learning-assisted framework that enables autonomous computational steering of scientific simulations and optimized execution of big-data workflows on heterogeneous platforms. This …

Development Of Super Hydrophobic Membranes And Their Applications, Sumona Paul

Dissertations

Effective liquid phase separation is vital across industries, especially in aviation, chemicals, fuels, and textiles. Membrane technology offers advantages over traditional methods like distillation, with low energy consumption and protection for heat-sensitive molecules. Membrane performance is assessed based on factors such as materials, surface modification, and interactions. This research targets superhydrophobic membranes for liquid-liquid filtration and antiwetting omniphobic membranes for membrane distillation, focusing on properties like contact angle and thermal resistance.

This study presents a highly hydrophobic membrane achieved by immobilizing carbon nanotubes (CNTs) onto a PTFE microfiltration membrane. It's designed for dewatering organic-water mixtures with trace water content via …

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Borrow Amendment Submittal #1 (Dated May 9, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Final Request For Change (Rfc-Rmap-2024-001), Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Development Of The Nebraska Department Of Transportation Winter Severity Index – Phase Ii, Mark Anderson, Curtis L. Walker, Thomas Kauzlarich

Nebraska Department of Transportation: Research Reports

For the Nebraska Department of Transportation (NDOT), the Nebraska Winter Severity Index (NEWINS) provided an independent framework to calculate a winter season’s severity by categorizing individual winter storms. However, one of the greatest limitations of NEWINS is that it is not predictive. Thus, this study builds on the previously developed NEWINS by creating a predictive winter storm severity index known as NEWINS-Predictive (NEWINS-P). The quantitative precipitation forecast, snow accumulation, ice accumulation, and surface wind speed parameters from the National Digital Forecast Database (NDFD) are used to develop the five components composing the NEWINS-P framework. These components consist of snow severity …

Plas 439: Organic Farming And Food Systems Faculty-Led Inquiry Into Reflective Scholarly Teaching Benchmark Portfolio, Christian Stephenson

UNL Faculty Course Portfolios

Organic Farming and Food Systems is a senior and graduate level course for students in the Department of Agronomy and Horticulture. This course was previously offered but has been significantly modified as I have taken on responsibility for the course. Goals for the course include student comprehension of the methods of organic and regenerative farming and the impacts of those methods on economic, environmental, and social sustainability. An additional goal is to build student competency in the evaluation of primary, secondary, and tertiary information resources and critical thinking surrounding issues in food production. Assessment for the course was through diverse …

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Request For Change (Rfc-Rmap-2024-001) (Dated May 9, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Unreclaimed Sites Field Sampling Plan (Fsp) Package #11: Ur-49 And Ur-50 (Dated May 6, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Request For Change (Rfc-Rmap-2024-001) (Dated May 9, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Unreclaimed Sites Field Sampling Plan (Fsp) Package #11: Ur-49 And Ur-50 (Dated May 6, 2024), Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

What Climate Change Means For Nebraska

United States Environmental Protection Agency: Publications

Nebraska’s climate is changing. In the past century, most of the state has warmed by at least one degree (F). The soil is becoming drier, and rainstorms are becoming more intense. In the coming decades, flooding is likely to increase, yet summers are likely to become increasingly hot and dry, which would reduce yields of some crops, require farmers to use more water, and amplify some risks to human health.

Our climate is changing because the earth is warming. People have increased the amount of carbon dioxide in the air by 40 percent since the late 1700s. Other heat-trapping greenhouse …

Reevaluating Texas Energy Market Forecasts In The Wake Of Recent Extreme Weather Events, Robert A. Derner, Richard W. Butler Ii, Alexandria Neff, Adam R. Ruthford

SMU Data Science Review

This paper provides updated forecasts of energy demand in Texas and recognizes the impact of sustainable energy. It is important that the forecasts of the adoption of sustainable energy are reexamined after Winter Storm Uri crippled the Texas power grid and left many without power. This storm highlighted the issues the Texas power grid had and has continued to struggle with in supplying the state with energy. This paper will offer an overview of the relevant literature on the adoption of sustainable energy and relevant events that have occurred in the state of Texas that will give the reader the …

Re: Conditional Approval Letter Butte Priority Soils Operable Unit Grove Gulch Sedimentation Bay 100% Remedial Design (Dated March 22, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Silver Bow Creek Conservation Area Repository Data Gap Quality Assurance Project Plan (Qapp), Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Silver Bow Creek Conservation Area Repository Data Gap Quality Assurance Project Plan (Qapp), Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final Annual Operations And Maintenance (O&M) Report: Butte Treatment Lagoon (Btl) System – 2023, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Biotechnology For Sustainable Materials: Innovating Today For A Greener Tomorrow, Shashi Kant Bhatia, Saurabh Bhatia, Maria Eugenia Inda-Webb, Konstantina Kourmentza, Tae Seok Moon, Vijai Singh, Vishal Ahuja, Jingbo Li, Sanjeet Mehariya, Jikai Zhao

School of Earth, Environmental, & Marine Sciences Faculty Publications

No abstract provided.

Carbon Sequestration In Peatlands: Using Environmental Proxies To Understand The Impact Of A Changing Climate On Global Carbon Storage, Sarah Schuller, Don Sullivan

DU Undergraduate Research Journal Archive

Peatlands are a type of terrestrial wetland ecosystem in which consistently waterlogged conditions prevent the decomposition of organic matter. These conditions allow for sequestered carbon in plant matter to remain stored in the soil to such a great degree that peatlands store more carbon than all other vegetation types in the world combined. By inhibiting decomposition, the composition of water-rich peat soil remains representative of the environmental conditions during the period in which the peat was formed. The collected peat samples can then be utilized as environmental proxies to determine historical temperature, moisture, and carbon content and extrapolated to predict …

Du Undergraduate Showcase Abstracts: Research, Scholarship, And Creative Works, August Alexander, Kevin Summers, E. Paige Lloyd, Alyssa Aragon, Lauren Wols, Erica Larson, Colton Arciniaga, Lily Baeza, Ellie Barnett-Cashman, Sidney Barbier, Maverick Bartholomew, Ryan Bell, Trevor Briggs, Amanda Brown, Cory Marchi, Maddy Pontius, Jennifer Gallagher, Claire Kwok, Channing Bullock, Alex Mccollister, Kim Gorgens, Daniela Chavez, Yamilet Espinoza Nuñez, Giovanni Valladares Giron, William Christensen, Olivia Kachulis, Daniel Cierasynski, Brandon Cohen, Spenser Dobbs, Lindsay Goolsby, Noah Craver, Nyah Cubbison, Liam Doherty, Nicole Doris, Yan Qin, Alexander Nguyen, Lily Harmon, Shubh Todi, Naichen Zhao, Noah Fagello, Stacia Fritz, Paola Gascot-Chinea, Alex Volkova, Janelyn Geronimo, Elsie Harrington, Shane Simmons, Clarice Hise, Laura Moreno Palmer, Henry Xu, Yesu Leela Pasupula, Emily Fisher, Zachary Hogan, Colin Kleckner, Alyssa Knaus, Erin Kubat, Sam Werkema, Katie Lamberton, Lilliya Larson, Allie Leary, Vanessa Leon-Gamez, James H. Gallagher, E. Dale Broder, Robin M. Tinghitella, Emma Loeber, Alina Mali, Ixchel Marquez, Lauren Mcgrath, Ella Matthews, Grace Naegelen, Audrey Ng, Megan Lucyshyn, Rachel Brough, Alexandra Norman, Joe Ontiveros Rodriguez, Ben Dossett, Ori Miller, Janamejay Sharma, Christopher Reardon, Vincent Pandey, Regan Parish, Ren Pratt, Alisha Pravasi, Sanchari Das, Cari Reichel, Emma Robson, Victoria Rockwell, Jayce Rumsey, Steven Said, Norah Schroder, Alaina Smith, Shannon Murphy, Shujan A. Sharafeldeen, Stanley M. Kanai, James T. Nichols, David E. Clouthier, Macalia R. Augustus, Daniel Silva Rios, Scott Simpson, Anna Sparling, Chase Spurbeck, Kimberly Chiew, Christine Stadnik-Poteroba, Jacqueline Stephenson, Evelyn Stovin, Mia Supan, Lauren Tapper, Will Thrush, Anna Vogt, Michaela Walheim, Jon Weber, Hunter Whitehouse, Kansas Wood, Hayley Sayre, Lydia Mccann, Maread Mclaughlin, Kelly Krumrie, Olivia Wuttke

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Research Showcase.

Double Acting Liberation Of Ni And Co In The Pre-Treatment Process To Increase Recovery Of Nickel From Low-Grade Nickel Laterite, Eni Febriana, Muhamad Irham Mulyadi, Wahyu Mayangsari, Januar Irawan, Iwan Setiawan, Ahmad Maksum, Florentinus Firdiyono, Soesaptri Oediyani, Agus Budi Prasetyo, Johny W. Soedarsono

Journal of Sustainable Mining

This study highlights the effectiveness of employing double-acting liberation to release Ni and Co from the complex phases of the low-grade nickel laterite. It includes the addition of concentrated sulphuric acid and NaF as well as the heat treatment prior to roasting and leaching processes to improve the destruction of the complex phases contained. The finding describes that dehydration of iron sulfate and decomposition of the lizardite at a lower temperature, 270°C, were occurred in the pre-treatment process, followed by hematite formation in the roasting process. It subsequently accelerated Ni and Co extraction in the pregnant solution and omitted Fe …

Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru

Master's Theses

The development of each nation is dependent on its infrastructure, and nations are competing with others in infrastructure, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are cement and asphalt, which pose significant environmental challenges. This thesis explores the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. The study examines the impact of FA and CS percentages and the particle sizes of CS on the compressive strength, …

Estimating Increased Transient Water Storage With Increases In Beaver Dam Activity, Konrad Hafen, Joseph M. Wheaton, Brett B. Roper, Philip Bailey, William W. Macfarlane, Bethany T. Neilson, Christopher J. Tennant

Watershed Sciences Faculty Publications

Dam building by beaver (Castor spp.) slows water movement through montane valleys, increasing transient water storage and the diversity of residence times. In some cases, water storage created by beaver dam construction is correlated to changes in streamflow magnitude and timing. However, the total amount of additional surface and groundwater storage that beaver dams may create (and, thus, their maximum potential impact on streamflow) has not been contextualized in the water balance of larger river basins. We estimate the potential transient water storage increases that could be created at 5, 25, 50, and 100% of maximum modeled beaver dam capacity …

Effect Of Sex On The Accumulation Of Hepatic Mercury In Mallards Wintering In Louisiana, Latorya E. Mason

Master's Theses

The increase in mercury production through anthropogenic activities has led to a global crisis of mercury pollution that poses a significant threat to the health of both humans and wildlife. Aquatic ecosystems are especially at risk due to the creation of methylmercury, a toxic form of mercury, by sulfate-reducing bacteria in anoxic sediments and soils. Methylmercury enters the food chain where it bioaccumulates in individual organisms and then biomagnified with increasing trophic level. Aquatic birds are useful bioindicators of many pollutants, including mercury, due to their abundance and position in the food chain. Previous studies have primarily focused on mercury …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan

Coal Geology & Exploration

The adsorption and desorption mechanisms of coalbed methane (CBM) are foundational for revealing CBM accumulation mechanisms and achieving efficient CBM exploitation. Studies have indicated that coal reservoirs exhibit complex pore structures with fractal features, significantly influencing CBM adsorption at pore-solid interfaces. Based on a comparative analysis of several common adsorption models for gas-solid interfaces and a summary of their characteristics and applicable conditions, this study suggests that all these adsorption models still rely on the stationary assumption of adsorption selectivity for the description and application of CBM adsorption behavior at fractal interfaces while overlooking the scale invariance of the adsorption …

Evolutionary Mechanisms And Models Of Strain, Porosity, And Permeability Of Compacted Broken Coals, Li Lei, Lu Shouqing, Chu Tingxiang, Zhong Xiaoxing, Liu Chongyang, Ren Ting

Coal Geology & Exploration

Residual coal areas in caving zones of goaves in coal mines serve as primary sites for low-temperature reactions between coal and oxygen. Hence, exploring the evolutionary models of the strain, porosity, and permeability of coals in these areas holds great significance for gaining a deep understanding of the spontaneous combustion process and regularity of coals. Based on the self-developed experimental device for gas seepage in compacted broken coals, this study explored the evolutionary patterns of the strain, porosity, and permeability of compacted coals with single/mixed particle sizes during gas seepage. Furthermore, this study analyzed the variations in the strain, porosity, …

Carbon Microspheres In Natural Coke: Optical Microscopic Characteristics And Their Origin And Implications, An Yanfei, Chen Kaixin, Wang Yaqiao, Cheng Shuo, Huang Jian, He Shuyang, Wang Shengjian

Coal Geology & Exploration

Carbon microspheres (CMs) in natural coke are formed when coal seams undergo magma-induced rapid thermal metamorphism. Analyzing the origin of the optical microscopic characteristics of CMs assists in gaining deep insights into the rapid thermal carbonization and metamorphism of coals. This study examined the natural coke samples rich in CMs from Shitai Coal Mine in Huaibei, Anhui Province. Using experiments like high-resolution reflected polarized light microscopy and scanning electron microscopy (SEM), this study characterized the particle sizes, distribution, optical microscopic characteristics, and ultramicrofabrics of CMs in natural coke, revealing the origin and thermal evolution implications of their optical anisotropy. The …

Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars, Chai Jing, Hao Hongru, Yang Jianfeng, Gao Dengyan, Gao Kuiying, Chen Jianhua, Yang Lei, Liu Zeyu

Coal Geology & Exploration

To address potential safety hazards like microcrack initiation, deformation, and failure inside coal pillars, this study monitored the horizontal deformations of coal pillars using the Brillouin optical time-domain reflectometry (BOTDR)—a distributed optical fiber sensing technology. Firstly, this study established a method for converting the axial strain of optical fibers into horizontal deformations based on a theoretical analysis of the failure and bulking characteristics of coal pillars. Secondly, it determined the axial tensile response of metal-based cord-shaped sensing optical fibers by conducting laboratory tests. Then, it corrected the strain coefficient based on the deformation and failure patterns of coal pillars. Finally, …

Exploring A Fly Ash-Based Grouting Material For Toughening Through In Situ Polymerization Of Acrylamide, Zhang Yuehong, Wang Xiaodong, Wang Hai, Wu Boqiang, Ji Zhongkui, Zhu Shibin, Han Le, Feng Longfei

Coal Geology & Exploration

Efficiently controlling the water inflow (loss) of burnt rocks in the roof of coal mining faces requires grouting reinforcement materials with excellent compressive toughness. Silicate cement-based grouting materials, characterized by low costs, have been extensively applied to grouting reinforcement in coal mines. However, their hardened grout is susceptible to deformation, exhibiting poor toughness. By employing the in-situ polymerization of acrylamide (AM) for toughening, this study investigated the effects of AM, cross-linking agent, initiator, and water-cement ratio on the setting time, swelling capacity, compressive strength, and toughness index of the fly ash-based grouting materials. Furthermore, the microstructures of the hardened grout …

Some Reflections On The Application Of Machine Learning To Research Into The Theoretical System Of Mine Water Prevention And Control, Yao Hui, Yin Huichao, Liang Manyu, Yin Shangxian, Hou Enke, Lian Huiqing, Xia Xiangxue, Zhang Jinfu, Wu Chuanshi

Coal Geology & Exploration

The theoretical system of mine water prevention and control encompasses three fundamental aspects: disaster-causing mechanisms, risk evaluation, and disaster prediction. This theoretical system, having undergone rapid development over the past 20 years, aims to gain insights into the behavior characteristics of mine water and predict its evolutionary trend, thus serving the prevention and control of water disasters in mining areas. Applying machine learning, a powerful tool for data analysis and mining in the era of big data, to research into the theoretical system has garnered considerable attention. This study focuses on the specific applications of machine learning to the three …