Engineering Commons^™

Feasibility Study Of Energy Storage Technologies For Remote Microgrid’S Energy Management System, Md Habib Ullah

Electronic Theses and Dissertations

Energy storage systems (ESSs) play a significant role in remote microgrids energy management system (EMS) with the large penetration rate of renewable energy which is intermittent in nature. Energy storage improves system reliability and efficiency in remote microgrids by optimizing the power demand and generation to reduce operational costs. Moreover, it increases the dispatch ability of the energy sources in remote microgrid systems. Lead acid battery (PbA) can be used as an energy storage device in remote microgrids due to its low cost; however, the response rate, short life cycle, and depth of discharge (DoD) lead to high operational costs. …

Foundation Design Of Low Volume Roads: Evaluation And Performance, Alyssa Clemen

Electronic Theses and Dissertations

A majority of roads in the state of SD are low volume roads (LVRs). The SDDOT has developed simplified methods for LVR pavement thickness selection. These guides allow users to obtain recommended asphalt surfacing and base course layer thickness based on the subgrade support and the average daily traffic (ADT) of the road. The main objective of this study is to relate the surface condition of LVRs to their ADT, layer thicknesses, foundation material properties, and maintenance. A secondary objective was to evaluate if the Dynamic Cone Penetrometer (DCP) is an acceptable tool in determining the subgrade support by using …

Plasma Treatment Of Zinc Oxide Thin Film And Temperature Sensing Using The Zinc Oxide Thin Film, Al-Ahsan Talukder

Electronic Theses and Dissertations

Zinc oxide is a direct and wide bandgap, II-VI semiconductor. It has large exciton binding energy, large piezoelectric constant, strong luminescence, and high thermal conductivity. These properties make zinc oxide as a suitable material for various optoelectronic applications. Vacuum based processes of fabrication of zinc oxide thin film dominate the market for their better electrical and optical properties. In this work, zinc oxide thin films were prepared by easy and low cost solution method with oriented crystal growth along (002) plane. To improve electrical and optical property of the fabricated zinc oxide thin films, films were treated with oxygen, hydrogen, …

Efficiency And Reliability Analysis Of Ac And 380v Dc Data Centers, Bijen Raj Shrestha

Electronic Theses and Dissertations

The rapid growth of the Internet has resulted in colossal increase in the number of data centers. A data center consume a tremendous amount of electricity resulting in high operation cost. Even a slight improvement in the power distribution system of a data center could save millions of dollars in electricity bills. Benchmarks for both AC and 380V DC data centers are developed and efficiency analyses thereof have been performed for an entire year. The efficiency of the power distribution system can be increased if number of power conversion stages can be reduced and more efficient converters are used. Use …

Nanoscale Study Of Perovskite Solar Cells For Efficient Charge Transport, Nirmal Adhikari

Electronic Theses and Dissertations

The effect of temperature, humidity and water on the grain boundary potential and charge transport within the grains of pervoskite films prepared by sequential deposition technique. Grain boundary potential of perovskite films exhibited variation in electrical properties with humidity level, temperature and water concentration in methyl ammonium iodide solution. X-ray diffraction (XRD) indicates the formation of PbI₂ phase in perovskite film with increasing temperature, humidity and adding larger quantity of water in methyl ammonium iodide solution. It is found that optimum amount of lead iodide helps for the passivation of perovskite film. Spatial mapping of surface potential in the …

Impacts Of Land Use And Climate Changes On Hydrological Processes In South Dakota Watersheds, Manashi Paul

Electronic Theses and Dissertations

This study aims to evaluate the impacts of climate and land use change on the hydrology of South Dakota’s watersheds using the Soil and Water Assessment Tool (SWAT). The study analyzed the hydrologic impacts of climate and land use changes in two ways. The first aspect consists of characterizing hydrological changes between two recent decades in three representative watersheds – Bad River watershed, Skunk Creek watershed and Upper Big Sioux River watershed. Two historical land use maps (NLCD 1992 and 2011) were used to represent land use change on these watersheds, and two historical climate datasets (1981-1990 and 2005-2014) were …

Effects Of Defects On The Performance Of Hierarchical Honeycomb Metamaterials Realized Through Additive Manufacturing, Kazi Moshiur Rahman

Electronic Theses and Dissertations

Cellular metamaterials are of immense interest for many current engineering applications. Tailoring the structural organization of cellular structures leads to new metamaterials with superior properties providing lightweight and very strong/stiff structures. The incorporation of hierarchy to regular cellular structures enhances the properties and introduces novel tailorable metamaterials. For many complex cellular metamaterials, the only realistic manufacturing process is additive manufacturing (AM). The use of AM to manufacture large structures may lead to several types of defects during the manufacturing process, such as imperfect cell walls, irregular thickness, flawed joints, partially missing layers, and irregular elastic plastic behavior due to toolpath. …

Evaluating Steel Byproducts And Natural Minerals For Phosphate Adsorption From Agricultural Subsurface Drainage, Bjorn Sellner

Electronic Theses and Dissertations

The loss of phosphorus (P) from agricultural soils to surface waters is recognized as a key contributing factor to eutrophication in surface waters. Recent studies have shown that in addition to surface runoff, subsurface drainage can contribute substantially to the loss of P from soils. The use of adsorption materials to bind P has emerged as a promising technology for P removal. The objective of this study was to perform batch and column experiments to investigate the P adsorption potential of several materials for agricultural subsurface drainage treatment. Laboratory batch adsorption experiments were performed to determine the P adsorption capacities …

Nitrogen Gas Flooding For Naturally Fractured Carbonate Reservoir: Visualisation Experiment And Numerical Simulation, Zhaojie Song, Jirui Hou, Zhongchun Liu, Fenglan Zhao, Shijun Huang, Yong Wang, Jieheng Wu, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Tahe Naturally Fractured Carbonate Reservoir has implemented nitrogen gas flooding since 2013, with daily oil production of 7580 bbls and oil recovery increment of 0.83% by the end of 2015. However, the presence of fractures significantly affects gas swept volume and production performance, so large amount of oil reserves is poorly flooded due to gas channeling through fractures. The fluid flow mechanisms in fractured models were discussed in order to improve field gas flooding efficiency. Based on the geological constrains of Tahe Oilfield, fractured models with different apertures were fabricated using acrylic glass to model carbonate matrix wettability and for …

A Need For Evidence-Based And Multidisciplinary Research To Study The Effects Of The Interaction Of School Environmental Conditions On Student Achievement, Josephine Lau, Lily M. Wang, Clarence E. Waters, James A. Bovaird

Durham School of Architectural Engineering and Construction: Faculty Publications

With funding from the U.S. Environmental Protection Agency’s (EPA) Healthy Schools initiative, a research team from the University of Nebraska– Lincoln (UNL) is currently working on establishing how environmental conditions in K-12 school buildings impact student scholastic achievement. The objectives of the research project are: (1) to study comprehensively the impacts of a wide set of indoor environmental factors (including indoor air quality, thermal, lighting and acoustic conditions) on student achievement; (2) to investigate how these environmental conditions interact with each other to impact student achievement; (3) to rank order the environmental variables in terms of their relative impact on …

Fault Diagnosis Of Refrigerant Charge Based On Pca And Decision Tree For Variable Refrigerant Flow Systems, Jiangyan Liu, Huanxin Chen, Jiangyu Wang, Guannan Li, Haorong Li, Wenju Hu

Durham School of Architectural Engineering and Construction: Faculty Publications

Variable refrigerant flow (VRF) systems are easily subjected to performance degradation due to refrigerant leakage, mechanical failure or improper maintenance after years of operation. Ideal VRF systems should equip with fault detection and diagnosis (FDD) program to sustain its normal operation. This paper presents the fault diagnosis method for refrigerant charge faults of variable refrigerant flow (VRF) systems. It is developed based on the classification and regression tree (CART) algorithm. Data of the experimental VRF system is used to test the advantages of the CART method. Results show that the decision tree can achieve desirable diagnosis efficiency on undercharge faults, …

Tio2-Based Nanomaterials For Advanced Environmental And Energy-Related Applications, Xujie Lü, Baoyu Xia, Yefeng Yang, Hao Tang

Physics Faculty Publications

No abstract provided.

Effect Of Twisted Fiber Anisotropy In Cardiac Tissue On Ablation With Pulsed Electric Fields, Fei Xie, Christian W. Zemlin

Bioelectrics Publications

Background: Ablation of cardiac tissue with pulsed electric fields is a promising alternative to current thermal ablation methods, and it critically depends on the electric field distribution in the heart.

Methods: We developed a model that incorporates the twisted anisotropy of cardiac tissue and computed the electric field distribution in the tissue. We also performed experiments in rabbit ventricles to validate our model. We find that the model agrees well with the experimentally determined ablation volume if we assume that all tissue that is exposed to a field greater than 3 kV/cm is ablated. In our numerical analysis, we considered …

Cell Electrosensitization Exists Only In Certain Electroporation Buffers, Janja Dermol, Olga N. Pakhomova, Andrei G. Pakhomov, Damijan Miklavčič

Bioelectrics Publications

Electroporation-induced cell sensitization was described as the occurrence of a delayed hypersensitivity to electric pulses caused by pretreating cells with electric pulses. It was achieved by increasing the duration of the electroporation treatment at the same cumulative energy input. It could be exploited in electroporation-based treatments such as electrochemotherapy and tissue ablation with irreversible electroporation. The mechanisms responsible for cell sensitization, however, have not yet been identified. We investigated cell sensitization dynamics in five different electroporation buffers. We split a pulse train into two trains varying the delay between them and measured the propidium uptake by fluorescence microscopy. By fitting …

Cytosolic Dna Sensor Upregulation Accompanies Dna Electrotransfer In B16.F10 Melanoma Cells, Katarina Znidar, Masa Bosnjak, Maja Cemazar, Loree C. Heller

Bioelectrics Publications

In several preclinical tumor models, antitumor effects occur after intratumoral electroporation, also known as electrotransfer, of plasmid DNA devoid of a therapeutic gene. In mouse melanomas, these effects are preceded by significant elevation of several proinflammatory cytokines. These observations implicate the binding and activation of intracellular DNA-specific pattern recognition receptors or DNA sensors in response to DNA electrotransfer. In tumors, IFN β mRNA and protein levels significantly increased. The mRNAs of several DNA sensors were detected, and DAI, DDX60, and p204 tended to be upregulated. These effects were accompanied with reduced tumor growth and increased tumor necrosis. In B16. F10 …

The Next Billion: Lessons In Off-Grid Electricity Development From The Global South, Peter Mcdonough

Graduate Student Theses, Dissertations, & Professional Papers

Today about a third of the world’s population has no access to electricity, and another third has only limited access. Driven by the push for development on one hand and the reality of climate change on the other, a combination of for-profit companies, NGOs, missions, and aid organizations is looking for the silver bullet to sustainable electricity development. In order to understand the challenges facing off-grid electricity projects I used recent literature in the form of peer-reviewed journals, agency reports, news articles, and technical documents; stakeholder interviews; and on-site observations in selected case studies in Nepal, India, and Tanzania. In …

Analysis Of Ca²⁺ Mobilization Of Nanosecond Pulses In Cells, Iurii Semenov

Bioelectrics Publications

Exposure to nanosecond electric pulses (nsEPs) evokes transient rise of cytosolic free Ca²⁺ concentration ([Ca²⁺]i) in the cells. We quantified the external Ca²⁺ uptake, intracellular Ca²⁺ release and uncover interplay of these processes for CHO-K1 cells upon exposure to single 60 ns pulse in the range of amplitudes from 0 to 30 kV/cm. NsEPs are distinguished by the ability to electroporate intracellular membranes. We studied how duration of nsEPs is related to efficiency of intracellular membranes electroporation comparing ability of single 300-, 60- and 10 ns pulses to recruit Ca²⁺ from endoplasmic reticulum (ER) in respect to the uptake of …

Electrosensitization Assists Cell Ablation By Nanosecond Pulsed Electric Field In 3d Cultures, Claudia Muratori, Andrei G. Pakhomov, Shu Xiao, Olga N. Pakhomova

Bioelectrics Publications

Previous studies reported a delayed increase of sensitivity to electroporation (termed "electrosensitization") in mammalian cells that had been subjected to electroporation. Electrosensitization facilitated membrane permeabilization and reduced survival in cell suspensions when the electric pulse treatments were split in fractions. The present study was aimed to visualize the effect of sensitization and establish its utility for cell ablation. We used KLN 205 squamous carcinoma cells embedded in an agarose gel and cell spheroids in Matrigel. A local ablation was created by a train of 200 to 600 of 300-ns pulses (50 Hz, 300-600 V) delivered by a two-needle probe with …

The Protective Role Of Mlcp-Mediated Erm Dephosphorylation In Endotoxin-Induced Lung Injury In Vitro And In Vivo, Anita Kovacs-Kasa, Boris A. Gorshkov, Kyung-Mi Kim, Sanjiv Kumar, Stephen M. Black, David J. Fulton, Christiana Dimitropoulou, John D. Catravas, Alexander D. Verin

Bioelectrics Publications

The goal of this study was to investigate the role of MLC phosphatase (MLCP) in a LPS model of acute lung injury (ALI). We demonstrate that ectopic expression of a constitutively-active (C/A) MLCP regulatory subunit (MYPT1) attenuates the ability of LPS to increase endothelial (EC) permeability. Down-regulation of MYPT1 exacerbates LPS-induced expression of ICAM1 suggesting an anti-inflammatory role of MLCP. To determine whether MLCP contributes to LPS-induced ALI in vivo, we utilized a nanoparticle DNA delivery method to specifically target lung EC. Expression of a C/A MYPT1 reduced LPS-induced lung inflammation and vascular permeability. Further, increased expression of the …

Activation Of Dna Pattern Recognition Receptors After Plasmid Electrotransfer In Melanoma Cells And Tumors, Loree Heller, Masa Bosnjak, Katarina Znidar, Maja Cemazar

Bioelectrics Publications

(First sentence) In vivo electroporation or electrotransfer, the application of controlled electric pulses, enhances delivery of plasmid DNA to a wide variety of healthy tissues as well as tumor types.

A Dielectric Rod Antenna For Picosecond Pulse Stimulation Of Neurological Tissue, Ross A. Petrella, Karl H. Schoenbach, Shu Xiao

Bioelectrics Publications

A dielectrically loaded wideband rod antenna has been studied as a pulse delivery system to subcutaneous tissues. Simulation results applying 100-ps electrical pulse show that it allows us to generate a critical electric field for biological effects, such as brain stimulation, in the range of several centimeters. In order to reach the critical electric field for biological effects, which is similar to 20 kV/cm, at a depth of 2 cm, the input voltage needs to be 175 kV. The electric field spot size in the brain at this position is similar to 1 cm(2). Experimental studies in free space with …

Comparison Between Electropositive And Electronegative Cold Atmospheric-Pressure Plasmas: A Modelling Study, Ding X. Liu, Jia F. Li, Ai J. Yang, Xiao H. Wang, Ming Z. Rong, Michael G. Kong

Bioelectrics Publications

Cold atmospheric-pressure He + N₂ and He + O₂ plasmas are chosen as the representatives for electropositive and electronegative plasmas, of which the discharge characteristics are studied and then compared to each other by fluid models. As the increase of the impurity (N₂ or O₂) fraction from 0 to 10%, for He + N₂ plasmas the electron density and ion density increase, the spatiotemporal distributions of electron density, ion density, electron temperature and electron generation rate change a little. On contrast, for He + O₂ plasmas the electron density decreases, the ion density …

Laboratory Exercise- Mapping The Risk Of Structural Failure In Schools Due To An Earthquake, Joel Barker, Kimberly Sowards, Casey Webb

Engineering Applications of GIS - Laboratory Exercises

Utah’s present geology has been greatly dictated by tectonic stresses that have occurred over the last 0.7 Ga. A determining factor in much of this Geology is the Hingeline that runs through Salt Lake County. Throughout the history of the western North America, this has been an important weak zone. It is no surprise that this same zone is now home to the Wasatch Fault System, which accommodates some of the extension of Western North America. The steep mountains facing west toward Salt Lake City were formed from the tectonic processes of the Fault. The Wasatch Fault is a normal …

Laboratory Exercise X – Most Dangerous Places To Live In The United States Based On Natural Disasters, Joshua Alpers, Luke Kevan, Santiago Tovar

Engineering Applications of GIS - Laboratory Exercises

This laboratory assignment simulates the most dangerous places to live in the United States based on natural disasters. The natural disasters that will be used in this assignment include wild fires, earthquakes, landslides, hurricanes, tornadoes, and flooding. These inputs will be required in creating a heat map of the United States showing what locations are most likely to have a high probability of natural disasters.

Laboratory Exercise – Ideal Locations For A Family, Benjamin Barrett, Colin Esplin, Chris Garcia

Engineering Applications of GIS - Laboratory Exercises

Upon the successful completion of a college degree, many students (and their families) are offered job positions in various locations throughout the Unites States. As a result, these young families are tasked with the challenge of finding a suitable place to live in an area they are completely unfamiliar with. By using a model in ArcMap this task can be made much easier. In this lab a model will be created in ArcGIS Model Builder along with a corresponding map showing suitable locations.

Final Laboratory Project – Emergency Landing Site Map, John Chadwick, Daniel Pope, Todd Weichers

Engineering Applications of GIS - Laboratory Exercises

Utah County is constantly developing and expanding. New developments require new roads, new power lines, and changes to existing topography. GIS data is maintained and made available for the state of Utah by Utah AGRC (Automated Geographic Reference Center). GIS can be used to make an easy to update map that will display the current situation of roads, power lines, population density, and terrain. In this exercise a model will be created that will execute to create a map that will display safe emergency landing sites for recreational aircraft in Utah County.

Laboratory Exercise – Determining Evacuation Route For Deer Creek Dam Failure, Eleise Hinton, Matt Randall, Brian Packer

Engineering Applications of GIS - Laboratory Exercises

Deer Creek Reservoir holds a volume of approximately 153,000 acre-ft of water. All of this water is held back by Deer Creek dam. Below the dam, the Provo River flows through Provo Canyon and down into Provo before terminating at Utah Lake. While the chance of a dam break is considered unlikely, an extreme event such as a major earthquake could trigger a break. In the case of a dam break, residents of Provo who live in the flood path will need to know where to evacuate. This exercise will create a model to show the nearest evacuation sites for …

Laboratory Exercise — Safety On Roads, Elise Estep, Kyungmin Kim, Danielle Nixon

Engineering Applications of GIS - Laboratory Exercises

In transportation study area, safety is a great issue. GIS is appropriate to perform spatial analysis the accident history in define area. Specifically, GIS allow researchers to find an area or road segment that have high probability of any type of car accident such as Vehicle to Vehicle, Vehicle to Pedestrian, and Vehicle to Bicycle.

Final Laboratory Project - Finding The Ideal Camping Location In The Uintas, Jeffrey Baker, Josh Curtis, Ryan Egbert

Engineering Applications of GIS - Laboratory Exercises

GIS is used extensively by the United States Forest Service in mapping and research. Many resources are available online including raster data and shapefiles. The use of GIS tools allows for analyzing entire forests and finding specific points within large areas that meet certain criteria. The Ashley National Forest, High Uinta Mountains Wilderness, in northeastern Utah contains many shapefiles including roads, forest, highway, points of interest, lakes, streams, etc. The purpose of this lab is to use these available datasets to identify ideal locations to set up camp in the Uinta Mountains.

Child Safety Near Pot Shops In Denver, Jacob Flansberg, Elise Jackson, Amelia Theobald

Engineering Applications of GIS - Laboratory Exercises

Some major factors in deciding where one’s family should live include relative safety of the neighborhood, available green space such as parks and schools, grocery stores, and other commercial retail in the area. With the legalization of marijuana in states such as Colorado, proximity of these marijuana dispensaries has become another factor. The Normalized Difference Vegetation Index (NDVI) can be used as a measure of vegetation, and to determine areas with high levels of irrigated vegetation. Using ArcGIS Modelbuilder, the data from an NDVI analysis can be used to determine the proximity of marijuana shops to these types of greenspaces …