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Full-Text Articles in Engineering

Investigation Of Anomalous Data Trends During Coal Dust Explosibilty Testing, Jacob Lee Miller Jan 2021

Investigation Of Anomalous Data Trends During Coal Dust Explosibilty Testing, Jacob Lee Miller

Doctoral Dissertations

Coal dust explosibility is a health and safety concern that has been a recognized hazard for over 100 years. Initial testing by the Author using a Siwek 20L apparatus recorded a secondary maximum pressure at higher dust concentrations (1,000-7,000g/m3) with Pulverized Pittsburgh Coal (PCC). Higher dust concentrations are beyond the typical ASTM E1226 testing procedure but are possible in mining and processing scenarios. No reference documents have been discovered that show a secondary maximum pressure at higher dust concentrations. Literature reviewed identified that once a coal dust concertation generates a peak pressure, the pressure remains constant or decreases …


An Investigation Of Unsteady Thermal Exchange Processes In Geothermal Heat Exchangers, Ganesh Ravi Shanker Jan 2021

An Investigation Of Unsteady Thermal Exchange Processes In Geothermal Heat Exchangers, Ganesh Ravi Shanker

Doctoral Dissertations

“Geothermal heat exchangers, has become one of the highly recognized non conventional heat exchangers as they utilize renewable energy source earth to initiate the thermal energy transfer. However, these heat exchangers suffer from a expensive installation cost due to their conservative design model, thereby facilitating the need to identify and improve the design. In this dissertation, three gaps, which identifies improvement over conservative design were investigated, to assess the heat exchanger performance. In the first approach, borehole thermal and geometrical properties were investigated keeping the outlet leg of the heat exchanger as adiabatic, which neglects the thermal short-circuiting between the …


Experimental And Numerical Studies Of Novel Thermal Energy Storage Materials For Applications In Concrete And Energy Storage Systems, Wenyu Liao Jan 2021

Experimental And Numerical Studies Of Novel Thermal Energy Storage Materials For Applications In Concrete And Energy Storage Systems, Wenyu Liao

Doctoral Dissertations

In this work, several types of novel thermal energy storage (TES) materials and composites are explored, and a series of numerical simulation models and experimental protocols are developed to evaluate the potentials of these materials to be applied in concrete, pavement, and thermal energy storage systems.

The first two types of novel TES materials/composites are at the micro-scale, which use micro diatomite (DE) and cenosphere (Ceno) as carriers of phase change material (PCM), respectively. The third type of novel TES material is at the macro-scale, utilizing lightweight sand (LWS) and lightweight coarse aggregate as carriers to load PCM. The last …


Establishing Links Between Safety Culture, Climate, Behaviors, And Outcomes Of Long-Haul Truck Drivers, Carlton Washburn Jan 2021

Establishing Links Between Safety Culture, Climate, Behaviors, And Outcomes Of Long-Haul Truck Drivers, Carlton Washburn

Doctoral Dissertations

“This research examines the safety relationships between safety culture, safety influences, safety climate, and safety outcomes for long-haul truck drivers. The relationships focus on the intersection of the electronic logging device (ELD) technology, regulations, and truck drivers that fall into the lone-worker category. Truck drivers were interviewed to understand their beliefs, attitudes, practices, values, and behavior patterns aligned with the phase in of the ELD system. Large truck crashes during the same time period were analyzed to understand associations. Outcomes included both a safety culture and climate were established for long-haul truck drivers. Both positive and negative safety behaviors were …


Investigating The Focusing Effect Of Charge Geometry With Computer Simulations, Witness Plates, And High-Speed Videography, Kelly Ray Williams Jan 2021

Investigating The Focusing Effect Of Charge Geometry With Computer Simulations, Witness Plates, And High-Speed Videography, Kelly Ray Williams

Doctoral Dissertations

"Scaled distance is used to calculate a safe standoff radius from the detonation of a known mass of an explosive. It has been shown that varying only the geometry of the charge significantly overdrives regions of the blast wave potentially resulting in hazardous overpressure levels at scaled distance safe radii. Pressure transducers are used to measure overpressure surrounding spherical, cylindrical, and cubic charges to determine if bridge waves were formed at the edges between flat sides as seen in published studies of cylindrical charges. In the fireball field a witness plate is used to evaluate radial energy distribution with a …


Modeling For Off-Chip High-Speed Designs, Siqi Bai Jan 2021

Modeling For Off-Chip High-Speed Designs, Siqi Bai

Doctoral Dissertations

”Signal integrity (SI) and power integrity (PI) are essential for datacenter application. A typical datacenter rack consists of a switch on the top of the rack, servers, and storage units. Three SI/PI related problems for datacenter application are analyzed in this research.

The first topic is analysis on power via induced Quasi-quarter-wavelength resonance to reduce crosstalk. Using an analytical model and 3D full-wave simulation models, a physical explanation for the unexpected resonance in the differential signal pairs is proposed. Considering the difficulty in changing the pin map of the IC-package, several PCB layouts to eliminate the power via induced quasi-quarter-wavelength …


Inspire Newsletter Spring 2021, Missouri University Of Science And Technology. Inspire - University Transportation Center Jan 2021

Inspire Newsletter Spring 2021, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.


Inspire Newsletter Fall 2021, Missouri University Of Science And Technology. Inspire - University Transportation Center Jan 2021

Inspire Newsletter Fall 2021, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.


An Experimental Study Investigating The Impact Of Miscible And Immiscible Nitrogen Injection On Asphaltene Instability In Nano Shale Pore Structure, Mukhtar Elturki, Abdulmohsin Imqam Jan 2021

An Experimental Study Investigating The Impact Of Miscible And Immiscible Nitrogen Injection On Asphaltene Instability In Nano Shale Pore Structure, Mukhtar Elturki, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Miscible gas injection has become the most used enhanced oil recovery (EOR) method in the oil and gas industry. The deposition and precipitation of asphaltene during the gas injection process is one of the problems during the oil production process. The asphaltene can deposit and plug the pores, which reduces the permeability in a reservoir; thus, decreasing the oil recovery and increasing the production costs. This research investigates the nitrogen (N2) miscible and immiscible pressure injections on asphaltene instability in shale pore structures. First, a slim tube was used to determine the minimum miscibility pressure (MMP) of N2 to ensure …


Will Carbon Dioxide Injection In Shale Reservoirs Produce From The Shale Matrix, Natural Fractures, Or Hydraulic Fractures?, Sherif Fakher, Youssef Elgahawy, Hesham Abdelaal, Abdulmohsin Imqam Jan 2021

Will Carbon Dioxide Injection In Shale Reservoirs Produce From The Shale Matrix, Natural Fractures, Or Hydraulic Fractures?, Sherif Fakher, Youssef Elgahawy, Hesham Abdelaal, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Enhanced oil recovery (EOR) in shale reservoirs has been recently shown to increase oil recovery significantly from this unconventional oil and gas source. One of the most studied EOR methods in shale reservoirs is gas injection, with a focus on carbon Dioxide (CO2) mainly due to the ability to both enhance oil recovery and store the CO2 in the formation. Even though several shale plays have reported an increase in oil recovery using CO2 injection, in some cases this method failed severely. This research attempts to investigate the ability of the CO2 to mobilize crude …


Trust-Empowered, Iot-Driven Legitimate Data Offloading, Zakaria Maamar, Noura Faci, Fadwa Yahya, Ejub Kajan Jan 2021

Trust-Empowered, Iot-Driven Legitimate Data Offloading, Zakaria Maamar, Noura Faci, Fadwa Yahya, Ejub Kajan

All Works

In an IoT environment deployed on top of fog and/or cloud nodes, offloading data between nodes is a common practice that aims at lessening the burden on these nodes and hence, meeting some real-time processing requirements. Existing initiatives put emphasis on “when to offload” and “where to offload” using criteria like resource constraint, load balancing, and data safety during transfer. However, there is limited emphasis on the trustworthiness of those nodes that will accept the offloaded data putting these data at risk of misuse. To address this limited emphasis, this paper advocates for trust as a decision criterion for identifying …


Morphology-Dependent Resonances In Two Concentric Spheres With Variable Refractive Index In The Outer Layer: Analytic Solutions, Umaporn Nuntaplook, John A. Adam Jan 2021

Morphology-Dependent Resonances In Two Concentric Spheres With Variable Refractive Index In The Outer Layer: Analytic Solutions, Umaporn Nuntaplook, John A. Adam

Mathematics & Statistics Faculty Publications

In many applications constant or piecewise constant refractive index profiles are used to study the scattering of plane electromagnetic waves by a spherical object. When the structured media has variable refractive indices, this is more of a challenge. In this paper, we investigate the morphology dependent resonances for the scattering of electromagnetic waves from two concentric spheres when the outer shell has a variable refractive index. The resonance analysis is applied to the general solutions of the radial Debye potential for both transverse magnetic and transverse electric modes. Finally, the analytic conditions to determine the resonance locations for this system …


A Deblurring/Denoising Corrected Scintigraphic Planar Image Reconstruction Model For Targeted Alpha Theory, Charles Ross Schmidtlein, Matthew Maroun, Andrzej Krol, Howard Gifford, Lisa Bodei, Joseph O'Donoghue, Ida Häggström, Yuesheng Xu, Si Li Jan 2021

A Deblurring/Denoising Corrected Scintigraphic Planar Image Reconstruction Model For Targeted Alpha Theory, Charles Ross Schmidtlein, Matthew Maroun, Andrzej Krol, Howard Gifford, Lisa Bodei, Joseph O'Donoghue, Ida Häggström, Yuesheng Xu, Si Li

Mathematics & Statistics Faculty Publications

Scintigraphy is a common nuclear medicine method to image molecular target’s bio-distribution and pharmacokinetics through the use of radiotracers and gamma cameras. The patient’s images are obtained by using a pair of opposing large flat gamma ray detectors equipped with parallel-hole lead or tungsten collimators that preferentially detect gamma-rays that are emitted perpendicular to the plane of the detector. The resulting images form an anterior/posterior (A/P) planar image pairs. The obtained images are contaminated by noise and contain artifacts caused by gamma-ray attenuation, collimator penetration, scatter and other detrimental factors. Post-filtering of the images can reduce the noise, but at …


Telehealth Optimization – Role Of Clinical Athletic Trainers In Orthopedic/Sports Medicine Practice, Katie Harbacheck, Laura Grambo, Shaun Keefer, Eric Klein, Christine Boyd, Carolyn Ford-Hemann, Cameron D’Alpe, Steve Frick, Kevin Shea Jan 2021

Telehealth Optimization – Role Of Clinical Athletic Trainers In Orthopedic/Sports Medicine Practice, Katie Harbacheck, Laura Grambo, Shaun Keefer, Eric Klein, Christine Boyd, Carolyn Ford-Hemann, Cameron D’Alpe, Steve Frick, Kevin Shea

Clinical Practice in Athletic Training

Background: Prior to COVID-19, telehealth (TH) implementation in most health systems was minimal. The transition to high rates of TH was dramatic in response to COVID-19, and many health systems struggled to develop optimal, efficient TH workflows. Hypothesis/Purpose: The primary purpose of this study was to evaluate the role of clinically integrated athletic trainers (ATs) into the TH transition of a major orthopedic academic center through growth of TH visits as well as physician satisfaction. Methods: Workflows and tip sheets were designed to include considerations of TH visit increases, adoption of appropriate technology platforms and optimal staff models. The rapid …


Synthetic Approach Of Ternary Magnesium Niobate (Mg–Nb–O) Compounds, Md. Wasikur Rahman Jan 2021

Synthetic Approach Of Ternary Magnesium Niobate (Mg–Nb–O) Compounds, Md. Wasikur Rahman

Mechanical Engineering Faculty Publications

Magnesium based niobium oxides (Mg–Nb–O) were prepared by solid-state reactions owing to understand the function of transition metal oxides as promoters/catalysts for practical application. Magnesium niobate (Mg3Nb6O11) was synthesized for the first time in nearly pure form reported in this context. MgNb2O6 and Mg4Nb2O9 were prepared in oxidizing conditions; on the contrary, Mg3Nb6O11 preferred reducing environment. Stoichiometric mixtures of the precursor materials MgO, Nb2O5 and/or metallic Nb were annealed for the syntheses which revealed the effect of temperature on phase formation, reaction kinetics and heat of reaction. The products were examined by ex-situ, in-situ X-ray diffraction (XRD) and differential scanning …


Coordination, Adaptation, And Complexity In Decision Fusion, Weiqiang Dong Dec 2020

Coordination, Adaptation, And Complexity In Decision Fusion, Weiqiang Dong

Dissertations

A parallel decentralized binary decision fusion architecture employs a bank of local detectors (LDs) that access a commonly-observed phenomenon. The system makes a binary decision about the phenomenon, accepting one of two hypotheses (H0 (“absent”) or H1 (“present”)). The k 1 LD uses a local decision rule to compress its local observations yk into a binary local decision uk; uk = 0 if the k 1 LD accepts H0 and uk = 1 if it accepts H1. The k 1 LD sends its decision uk over a noiseless dedicated channel to a Data Fusion Center (DFC). The DFC combines the …


Development Of Novel Inks And Approaches For Printing Tissues And Organs, Shen Ji Dec 2020

Development Of Novel Inks And Approaches For Printing Tissues And Organs, Shen Ji

Dissertations

Tissue engineering is a multidisciplinary field that investigates and develops new methods to repair, regenerate and replace damaged tissues and organs, or to develop biomaterial platforms as in vitro models. Tissue engineering approaches require the fabrication of scaffolds using biomaterials or fabrication of living tissues using cells. As the demands of customized, implantable tissue/organs are increasing and becoming more urgent, conventional scaffold fabrication approaches are difficult to meet the requirements, especially for complex large-scale tissue fabrication. In this regard, three-dimensional (3D) printing attracted more interest over the past decades due to its unrivaled ability to fabricate highly customized tissues or …


Drone-Assisted Emergency Communications, Di Wu Dec 2020

Drone-Assisted Emergency Communications, Di Wu

Dissertations

Drone-mounted base stations (DBSs) have been proposed to extend coverage and improve communications between mobile users (MUs) and their corresponding macro base stations (MBSs). Different from the base stations on the ground, DBSs can flexibly fly over and close to MUs to establish a better vantage for communications. Thus, the pathloss between a DBS and an MU can be much smaller than that between the MU and MBS. In addition, by hovering in the air, the DBS can likely establish a Line-of-Sight link to the MBS. DBSs can be leveraged to recover communications in a large natural disaster struck area …


A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek Dec 2020

A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek

Dissertations

The introduction of deep learning and big data analytics may significantly elevate the performance of traffic speed prediction. Work zones become one of the most critical factors causing congestion impact, which reduces the mobility as well as traffic safety. A comprehensive literature review on existing work zone delay prediction models (i.e., parametric, simulation and non-parametric models) is conducted in this research. The research shows the limitations of each model. Moreover, most previous modeling approaches did not consider user delay for connected freeways when predicting traffic speed under work zone conditions. This research proposes Deep Artificial Neural Network (Deep ANN) and …


Human-Robot Interaction For Assistive Robotics, Jiawei Li Dec 2020

Human-Robot Interaction For Assistive Robotics, Jiawei Li

Dissertations

This dissertation presents an in-depth study of human-robot interaction (HRI) withapplication to assistive robotics. In various studies, dexterous in-hand manipulation is included, assistive robots for Sit-To-stand (STS) assistance along with the human intention estimation. In Chapter 1, the background and issues of HRI are explicitly discussed. In Chapter 2, the literature review introduces the recent state-of-the-art research on HRI, such as physical Human-Robot Interaction (HRI), robot STS assistance, dexterous in hand manipulation and human intention estimation. In Chapter 3, various models and control algorithms are described in detail. Chapter 4 introduces the research equipment. Chapter 5 presents innovative theories and …


Experiments And Modeling Of The Chemo-Mechanically Coupled Behavior Of Polymeric Gels, Nikola Bosnjak Dec 2020

Experiments And Modeling Of The Chemo-Mechanically Coupled Behavior Of Polymeric Gels, Nikola Bosnjak

Dissertations

Polymeric materials consist of mutually entangled or chemically crosslinked long njitmolecular chains which form a polymer network. Due to their molecular structure, the njitpolymeric materials are known to undergo large deformation in response to various njitenvironmental stimuli, such as temperature, chemical potential and light.

When a polymer network is exposed to a suitable chemical solvent, the solvent molecules are able to diffuse inside the network, causing it to undergo a large volumetric deformation, known as swelling. In addition to volumetric deformation, this process involves the chemical mixing of the polymer network and solvent molecules, and is typically environmentally responsive. A …


High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv Dec 2020

High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv

Dissertations

This study uses a complex network model to analyze the causes of accidents in high-speed railway operations. By identifying the key factors that led to high-speed railway accidents, hidden safety hazards were discovered. This will help improve the operational safety of the U.S. high-speed rail line under construction.

The analysis uses the regional high-speed railway network in Guangzhou, China as a case study, including the railway (including high-speed railway) accidents that occurred in the company's jurisdiction from 2013 to 2017. With comparative analysis between general railways and high-speed railways, the changes of high-speed railway safety factors are explored. Data analysis …


Dances And Escape Of The Vortex Quartet, Brandon Behring Dec 2020

Dances And Escape Of The Vortex Quartet, Brandon Behring

Dissertations

This dissertation considers the linear stability of a one-parameter family of periodic solutions of the four-vortex problem known as 'leapfrogging' orbits. These solutions, which consist of two pairs of identical yet oppositely-signed vortices, were known to W. Gröbli (1877) and A. E. H. Love (1883) and can be parameterized by a dimensionless parameter related to the geometry of the initial configuration. Simulations by Acheson and numerical Floquet analysis by Tophøj and Aref both indicate, to many digits, that the bifurcation occurs at a value related to the inverse square of the golen ratio. Acheson observed that, after an initial period …


Online Fulfillment: F-Warehouse Order Consolidation And Bops Store Picking Problems, Wen Zhu Dec 2020

Online Fulfillment: F-Warehouse Order Consolidation And Bops Store Picking Problems, Wen Zhu

Dissertations

Fulfillment of online retail orders is a critical challenge for retailers since the legacy infrastructure and control methods are ill suited for online retail. The primary performance goal of online fulfillment is speed or fast fulfillment, requiring received orders to be shipped or ready for pickup within a few hours. Several novel numerical problems characterize fast fulfillment operations and this research solves two such problems. Order fulfillment warehouses (F-Warehouses) are a critical component of the physical internet behind online retail supply chains. Two key distinguishing features of an F-Warehouse are (i) Explosive Storage Policy – A unique item can be …


Characterizing Reactive Iron Mineral Coatings And Their Roles In Natural Attenuation At A Site With Historical Contamination, Han Hua Dec 2020

Characterizing Reactive Iron Mineral Coatings And Their Roles In Natural Attenuation At A Site With Historical Contamination, Han Hua

Dissertations

Reactive iron mineral coatings in redox transition zones play an important role in contaminant attenuation. These mineral coatings include poorly crystalline to crystalline iron sulfides, carbonates, and oxyhydroxides, and are a signature of the biogeochemical processes occurring. To better understand these processes, reactive iron mineral coatings are characterized in an 18-m Anaerobic Core collected from a contaminated industrial site. This study targets redox transition zones uncovered in the core. A suite of complementary analyses is applied to distinguish the surface coating mineralogy using X-ray Diffraction, X-ray fluorescence, and field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray analyzer (EDX). In …


The Aging And Impacts Of Atmospheric Soot: Closing The Gap Between Experiments And Models, Ogochukwu Yvonne Enekwizu Dec 2020

The Aging And Impacts Of Atmospheric Soot: Closing The Gap Between Experiments And Models, Ogochukwu Yvonne Enekwizu

Dissertations

The main goal of this dissertation is to generate data and parameterizations to accurately represent soot aerosols in atmospheric models. Soot from incomplete combustion of fossil fuels and biomass burning is a major air pollutant and a significant contributor to climate warming. The environmental impacts of soot are strongly dependent on the particle morphology and mixing state, which evolve continuously during atmospheric transport via a process known as aging. To make predictions of soot impacts on the environment, most atmospheric models adopt simplifications of particle structure and mixing state, which lead to substantial uncertainties. Using an experimentally constrained modeling approach, …


Performance Optimization Of Big Data Computing Workflows For Batch And Stream Data Processing In Multi-Clouds, Huiyan Cao Dec 2020

Performance Optimization Of Big Data Computing Workflows For Batch And Stream Data Processing In Multi-Clouds, Huiyan Cao

Dissertations

Workflow techniques have been widely used as a major computing solution in many science domains. With the rapid deployment of cloud infrastructures around the globe and the economic benefits of cloud-based computing and storage services, an increasing number of scientific workflows have migrated or are in active transition to clouds. As the scale of scientific applications continues to grow, it is now common to deploy various data- and network-intensive computing workflows such as serial computing workflows, MapReduce/Spark-based workflows, and Storm-based stream data processing workflows in multi-cloud environments, where inter-cloud data transfer oftentimes plays a significant role in both workflow performance …


The Stability Of Nanobubbles And Its Application In Contaminated Sediment Treatment, Shaini Dilsha Aluthgun Hewage Dec 2020

The Stability Of Nanobubbles And Its Application In Contaminated Sediment Treatment, Shaini Dilsha Aluthgun Hewage

Dissertations

This dissertation consists of two sections. First, nanobubbles' stability and behavior are studied using experimental and theoretical approaches. Second, nanobubbles application combined with ultrasound to remediate contaminated sediments is discussed.

The stability study consists of four sections. (i). Laboratory investigation to determine bubble size distributions and zeta potentials for different gases, pH levels, temperatures, and salt conditions. (ii). A theoretical study based on the diffused double layer theory to explain nanobubbles' behavior in different NaCl concentrations. (iii). Nanobubbles' stability in electrolyte solutions under different ion valencies using deionized water, NaCl, Na2SO4, Na3PO4, …


Modeling Mass Transfer And Chemical Reaction In Industrial Nitrocellulose Manufacturing Processes, Francis Patrick Sullivan Dec 2020

Modeling Mass Transfer And Chemical Reaction In Industrial Nitrocellulose Manufacturing Processes, Francis Patrick Sullivan

Dissertations

A series of models are proposed to describe the production of military grade nitrocellulose from dense cellulose materials in mixtures of nitric acid, sulfuric acid, and water. This effort is conducted to provide a predictive capability for analyzing the rate and extent of reaction achieved under a range of reaction conditions used in the industrial nitrocellulose manufacturing process for sheeted cellulose materials. Because this capability does not presently exist, nitrocellulose producers have historically relied on a very narrow range of cellulose raw materials and resorted to trial and error methods to develop processing conditions for new materials. This tool enables …


2020 Scholarly Productivity Report, Missouri University Of Science And Technology Dec 2020

2020 Scholarly Productivity Report, Missouri University Of Science And Technology

Civil, Architectural and Environmental Engineering Scholarly Productivity Reports

No abstract provided.