Engineering Commons^™

Investigating Optimum Wavelength(S) For Growth Of Lactuca Sativa, L. Using Tunable Led Sources And Developing Thin-Film Filters For Glass Greenhouses, Jacqualine Anne Thomas

Theses: Doctorates and Masters

With the increase in world population, the continued advances in modern greenhouse agriculture and plant growth practices are expected to help overcome the global problem of future food shortages. This research investigates a way to assist in stemming the problem of food shortage by using optimised light irradiation (within the constraints of the experiment) on a sample plant species of lettuce (Lactuca sativa, L.). Whilst lettuce is often grown in hydroponic systems, the current research is conducted in stand-alone pots with hand watering, due to the requirements of health and safety and available resources.

The experiments were designed …

Towards Overcoming The Curse Of Dimensionality In Predictive Modelling And Uncertainty Quantification, Dan Gabriel Cacuci

Faculty Publications

This invited presentation summarizes new methodologies developed by the author for performing high-order sensitivity analysis, uncertainty quantification and predictive modeling. The presentation commences by summarizing the newly developed 3rd-Order Adjoint Sensitivity Analysis Methodology (3rd-ASAM) for linear systems, which overcomes the “curse of dimensionality” for sensitivity analysis and uncertainty quantification of a large variety of model responses of interest in reactor physics systems. The use of the exact expressions of the 2nd-, and 3rd-order sensitivities computed using the 3rd-ASAM is subsequently illustrated by presenting 3rd-order formulas for the first three cumulants of the response distribution, for quantifying response uncertainties (covariance, skewness) …

Proteomic Analysis Of Fetal Rat Neural Stem Cells After Treatment With Hericium Erinaceus, Bright Adam Test

University of the Pacific Theses and Dissertations

The fungus, Hericium erinaceus, has outstanding chemical properties, displaying health benefits in digestive, hepatic, and nervous tissues. Its ease of accessibility and use makes it one of the most common substances used for treatment in Eastern medicine. More and more recent research is confirming the incredible health benefits of this fungus, especially the impact that is seen on nervous tissue growth and recovery post-treatment. Such neurite outgrowth and myelin sheath regeneration could illustrate the beginning of the cure to lifelong neurodegenerative diseases such as Multiple Sclerosis. In this first-of-its-kind study, we cultured and differentiated fetal rat neural stem cells while …

Smart Communities: From Sensors To Internet Of Things And To A Marketplace Of Services, Stephan Olariu, Nirwan Ansari (Editor), Andreas Ahrens (Editor), Cesar Benavente-Preces (Editor)

Computer Science Faculty Publications

Our paper was inspired by the recent Society 5.0 initiative of the Japanese Government that seeks to create a sustainable human-centric society by putting to work recent advances in technology: sensor networks, edge computing, IoT ecosystems, AI, Big Data, robotics, to name just a few. The main contribution of this work is a vision of how these technological advances can contribute, directly or indirectly, to making Society 5.0 reality. For this purpose we build on a recently-proposed concept of Marketplace of Services that, in our view, will turn out to be one of the cornerstones of Society 5.0. Instead of …

Exploring Strategies For Adapting Traditional Vehicle Design Frameworks To Autonomous Vehicle Design, Alex Munoz

Walden Dissertations and Doctoral Studies

Fully autonomous vehicles are expected to revolutionize transportation, reduce the cost of ownership, contribute to a cleaner environment, and prevent the majority of traffic accidents and related fatalities. Even though promising approaches for achieving full autonomy exist, developers and manufacturers have to overcome a multitude of challenged before these systems could find widespread adoption. This multiple case study explored the strategies some IT hardware and software developers of self-driving cars use to adapt traditional vehicle design frameworks to address consumer and regulatory requirements in autonomous vehicle designs. The population consisted of autonomous driving technology software and hardware developers who are …

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …

Exploring The Career Experiences Of Immigrant Nigerian Women Engineers, Ijeoma Lilian Ozoude

Walden Dissertations and Doctoral Studies

The contribution of immigrant Science, Technology, Engineering and Mathematics (STEM) workers in addressing the projected shortage of U.S. STEM workforce cannot be overemphasized. Despite efforts by U.S. policy makers to provide opportunities for a positive STEM experience and diversify the STEM field by increasing the number of underrepresented minorities and women via The Women and Minorities in STEM Booster Act, changes to the U.S. immigration policy towards Nigeria, including bans on immigrant visas and Diversity visas could impact recruitment of immigrant Nigerian workers in STEM. Using Kingdon’s multiple streams framework and Crenshaw’s intersectionality theory, this study explored the career experiences …

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …

Chlorophyll-Inspired Tunable Metamaterials With Multi-Negative Refractive Index Bands: The Porphyrin Ring And Hydrophobic Tail Effect, Nantakan Wongkasem

Electrical and Computer Engineering Faculty Publications

Tunable negative electromagnetic properties: permittivity, permeability, and refractive index, in mimic Chlorophyll metamaterial structures in the X- and Ku-band regimes are theoretically and numerically demonstrated. A very broad negative permeability covering the majority of the X- and Ku bands, from 8GHz to 16GHz, is observed, while five negative permittivity bands are found within the same range. The two aforementioned properties result in a broad, greater than 25% bandwidth, low-loss negative-refractive index transmission band. These negative electromagnetic properties can be effectively tailored within the low-loss multi-transmission and the high-loss multi-absorption bands in the operating frequency range by modifying the structure’s tiller …

Ensemble Node Embeddings Using Tensor Decomposition: A Case-Study On Deepwalk, Jia Chen, Evangelos E. Papalexakis

Electrical and Computer Engineering Faculty Publications

Node embeddings have been attracting increasing attention during the past years. In this context, we propose a new ensemble node embedding approach, called TENSEMBLE2VEC, by first generating multiple embeddings using the existing techniques and taking them as multiview data input of the state-of-art tensor decomposition model namely PARAFAC2 to learn the shared lower-dimensional representations of the nodes. Contrary to other embedding methods, our TENSEMBLE2VEC takes advantage of the complementary information from different methods or the same method with different hyper-parameters, which bypasses the challenge of choosing models. Extensive tests using real-world data validates the efficiency of the proposed method.

Impact Of The Arrival Distribution Of Primary User Traffic In Dynamic Spectrum Access, Jun Peng

Electrical and Computer Engineering Faculty Publications

In dynamic spectrum access (DSA) a primary user shares the spectrum with one or more secondary users, with or without the primary user knowing the existence of the secondary users and offering assistance to the secondary users. When the primary user is inactive in the channel, the secondary users use the spectrum for data communication. When the primary user becomes active, the secondary users back off to return the spectrum back to the primary user. It is therefore that an arrival of the primary user traffic interrupts the ongoing communication among the secondary users. The arrivals of the primary user …

Deep Learning Based Face Detection And Recognition In Mwir And Visible Bands, Suha Reddy Mokalla

Graduate Theses, Dissertations, and Problem Reports (ETD)

In non-favorable conditions for visible imaging like extreme illumination or nighttime, there is a need to collect images in other spectra, specifically infrared. Mid-Wave infrared (3-5 microm) images can be collected without giving away the location of the sensor in varying illumination conditions. There are many algorithms for face detection, face alignment, face recognition etc. proposed in visible band till date, while the research using MWIR images is highly limited. Face detection is an important pre-processing step for face recognition, which in turn is an important biometric modality. This thesis works towards bridging the gap between MWIR and visible spectrum …

Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil

Graduate Theses, Dissertations, and Problem Reports (ETD)

The life-cycle performance, durability, and aging characteristics of Fiber Reinforced Polymer (FRP or Structural Composites) have been of keen interest to the engineers engaged in the FRP design, construction, and manufacturing. Unlike conventional construction materials such as steel and concrete, the design guidelines to account for the aging of FRP are somewhat scattered or not available in an approved or consistent format. Loss of strength over time or aging of any structural material should be of concern to engineers as the in-service lifespan of many engineering structures is expected to exceed 100 years. Use of durability strength-reduction factors or factors …

An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Improving the quality of equipment training for the Heavy Equipment Operators (HEO) is a critical task in the ever-lasting effort to improve safety and eliminate equipment-related injuries in mining environments. Traditional miner training includes the use of hardcopy documents and video instructions. However, modern mobile and computer technology offers tremendous potential to improve the training process. One major responsibility for the heavy-machine operators is proper machine inspection. Establishing new training methods that utilize modern technologies—such as 360-degree images, videos, and Virtual Reality—and implementing computers for training purposes have a potential to help new operators learn how to conduct proper machine …

Experimental, Computational And Analytical Studies Towards A Predictive Scenario For A Burning Accident, Furkan Kodakoglu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Historically, accidental gas and dust explosions constitute one of the major hazards to both personnel and equipment in the process industries. The current knowledgebase on such explosions does not provide an acceptable level of risk. Therefore, novel preventive mining/fire safety strategies, based on a rigorous predictive scenario for burning accidents, are critically needed. The present dissertation is devoted to such a predictive scenario, with a particular focus on the flame and pressure evolutions in explosions encountered in an enclosure with or without obstructions. The experimental component of this dissertation comprises a series of experiments on explosion venting. Specifically, the influence …

Towards Large Eddy Simulation Of A Staged, Pressurized Oxy-Fuel Combustor, Alain Islas Montero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Identified by the DoE among the novel and transformational technologies, staged-pressurized oxy-fuel combustion (SPOC) is a promising low-cost, low-emission, and highly efficient tool for carbon capture utilization and storage (CCUS), with pulverized coal burning under elevated pressures and low recycled flue gas. A lab-scale SPOC facility, under establishment at Washington University in St. Louis (WUSTL), causes the critical need to develop accurate and reliable computational models to assist the ongoing WUSTL experiments. This constitutes the driving motivation of the present work. Specifically, comprehensive three-dimensional Large-eddy simulations (LES) of the lab-scale SPOC reactor, with most of important characteristics of a multi-phase …

Comparative Study Of Model-Based And Learning-Based Disparity Map Fusion Methods, Douglas E. Kerr Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Creating an accurate depth map has several, valuable applications including augmented/virtual reality, autonomous navigation, indoor/outdoor mapping, object segmentation, and aerial topography. Current hardware solutions for precise 3D scanning are relatively expensive. To combat hardware costs, software alternatives based on stereoscopic images have previously been proposed. However, software solutions are less accurate than hardware solutions, such as laser scanning, and are subject to a variety of irregularities. Notably, disparity maps generated from stereo images typically fall short in cases of occlusion, near object boundaries, and on repetitive texture regions or texture-less regions. Several post-processing methods are examined in an effort to …

Development Of An Activity-Based Windowing Approach To Evaluate Real-World Nox Emissions From Modern Medium And Heavy-Duty Diesel Trucks, Rasik Pondicherry

Graduate Theses, Dissertations, and Problem Reports (ETD)

The introduction of in-use emissions regulations by the United States Environmental Protection Agency (U.S.EPA) requires medium-duty (MD) and heavy-duty (HD) engine manufacturers to demonstrate emissions compliance during in-fleet operation. In the United States (U.S.), the Not-to-Exceed (NTE) method is used to evaluate real-world emissions compliance from on-highway MD and HD trucks. Regulatory agencies, engine manufacturers and research entities have identified that the NTE method incorporates numerous exclusions and evaluates emissions compliance only under selective operating conditions that are favorable for the selective catalytic reduction (SCR) system to reduce oxides of nitrogen (NOx) emissions efficiently. Such operation is typically encountered only …

Interoperability Of Ip-Based Cameras, Faythe C. Maston

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this day and age of advancing technology and increasing crime, more and more citizens are investing in technology to increase their personal security. One such technology is the use of home-based IP security systems. These systems are comprised of one or more IP-based security cameras with owners preferring to have a way to view all camera feeds at once. Since not all security cameras are made to interact with each other, it is necessary to find a program that allows a user to view all security cameras at once, regardless of what brand of cameras they use. After researching, …

Techno-Economic Feasibility Of Solar Powered Electric Vehicle Charging Stations In West Virginia, Houssem Eddine Younes

Graduate Theses, Dissertations, and Problem Reports (ETD)

This project explores the techno-economic feasibility of installing a photovoltaic (PV) system to power electric vehicle (EV) charging stations in West Virginia. A case study of a parking garage charging station is considered. The PV system performance and economic feasibility are assessed for two different system configurations and two financial scenarios. Two system variations one including PV only and another with on-site storage battery are modelled using the System Advisor Model (SAM) developed by the National Renewable Energy Laboratory. Initial technical specifications of the PV system, battery system and EV chargers were selected as a reference case. Through parametric simulation, …

Scaling-Based Robust Predictions Of Periodic Stream Water Quality Variables Across The Contiguous U.S., Mohammad Abu Zafer Siddik

Graduate Theses, Dissertations, and Problem Reports (ETD)

Stream water quality is at the core of the biological and ecological health of streams and rivers. Subject to the environmental variation and in-stream metabolic activities, key water quality indicators such as dissolved oxygen (DO), water temperature (Tw), and chlorophyll a (Chl a, an indicator of primary productivity) typically follow a concave-shaped diurnal cycle. Variation and changes in climatic drivers (e.g., solar radiation, air temperature, and pressure), land uses, and hydrologic variables lead to a high spatiotemporal variability in stream water quality. The spatiotemporal variation challenges the development of robust models for predictions across large scales (e.g., county, state, country), …

Integrated Techno-Economic And Life Cycle Analyses Of Biomass Utilization For Value-Added Bioproducts In The Northeastern United States, Yuxi Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

A multi-stage spatial analysis was first conducted to select locations for lignocellulosic biomass-based bioproduct facility, using Geographical Information System (GIS) spatial analysis, multi-criteria analysis ranking algorithm, and social-economic assessment. A case study was developed to determine locations for lignocellulosic biorefineries using feedstocks including forest residue biomass and three energy crops for 13 states in the northeastern United States. In the entire study area, 11.1% of the counties are high-suitable, 48.8% are medium-suitable for biorefinery siting locations. A non-parametric analysis of cross-group surveys showed that preferences on biorefinery siting are homogeneous for experts in academia and industry groups, but people in …

Modulation Of Semiconductor Photoconversion With Surface Modification And Plasmon, Joeseph Martin Bright

Graduate Theses, Dissertations, and Problem Reports (ETD)

Semiconductor devices are the basis of modern technology. Semiconductor-based photoconversion devices that convert light into electrical signals have shown potential for light energy harvesting and conversion, environmental remediation, and sensors for detection of light, chemicals, and biological substances. Despite this potential for use in many applications, semiconductor photoconversion devices need further improvement in the photoconversion performance. This photoconversion improvement may be manifested as increased photoconversion efficiencies for light harvesting devices for power generation such as photovoltaics and photoelectrochemical (PEC) cells or improved photoconversion modulation to increase the sensitivity of semiconductor photoconversion-based sensors. In addition, alternative semiconductor materials to semiconductors that …

Programming Of Floating-Gate Transistors For Nonvolatile Analog Memory Array, Haifa Abulaiha

Graduate Theses, Dissertations, and Problem Reports (ETD)

Since they were introduced, floating-gate (FG) transistors have been used as non-volatile digital memory. Recent research has shown that floating-gate transistors can be successfully used as analog memory, specifically as programmable voltage and current sources. However, their proliferation has been limited due to the complex programming procedure and the complex testing equipment. Analog applications such as field-programmable analog arrays (FPAAs) require hundreds to thousands of floating-gate transistors on a single chip which makes the programming process even more complicated and very challenging. Therefore, a simplified, compact, and low-power scheme to program FGs are necessary. This work presents an improved version …

Adaptation Of Coal Mine Floor Rating (Cmfr) To Eastern U.S. Coal Mines, Sena Cicek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Floor heave—the excessive deformation and failure of floor strata—is a serious problem for many underground coal mining operations in the U.S. There is an accepted floor heave design methodology developed for the Illinois basin coal mines (Gadde, 2009). However, for Eastern U.S. coal mines in the Appalachian region, there is not any systematic design method to assess floor heave potential. In order to prevent stability problems associated with floor failure and to ensure the safety of the miners in this region, a systematic and proactive method to assess the potential of floor stability that also takes the floor failure mechanisms …

Multi-Objective Optimization Of A Ridesharing System Performance, Mohammad Nasr Azadani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ridesharing is a shared vehicle service with the potential to meet the growing travel demand due to population increase, economic growth, and shortage in transportation infrastructure capacity. Compared to the current system of predominantly using personal vehicles, ridesharing services reduce the number of vehicles while providing mobility services to the same number of people with no additional investment in the transportation infrastructure. One of the big challenges in implementing ridesharing services is matching drivers and riders. Conflicts between matching-objectives to comply with the interests of diverse stakeholders influence the efficiency of ridesharing in a transportation system. This study investigates the …

Characterizing Premixed Syngas Combustion In Micro-Channels, Sunita Pokharel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increasing demands in the next-generation portable power-generation devices such as unmanned aerial vehicles (UAV), microsatellite thrusters, micro-chemical reactors and sensors calls for fuels with high specific energy and low emissions to meet the current demand of green energy. Fuel-lean synthesis gas (syngas) meets both these requirements exhibiting a promising route to a clean and green environment. Thus, it is of critical importance to characterize syngas combustion and understand its properties in the micro-combustion industry. In addition to complicated flame dynamics in microscale systems, varying the syngas-fuel mixture composition as well as the boundary conditions and geometry of a combustor significantly …

Experimental And Field Evaluation Of Frp Pedestrian Bridge Decks, Kalrav Singh Tomer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Traditional materials such as steel, timber, and concrete have continued to dominate their usage in civil infrastructure. They offer great advantages like strength and stiffness but at the same time they pose major issues in terms of durability and maintenance. Fiber reinforced polymer (FRP) exhibits outstanding properties like lightness, excellent corrosion and wear resistance along with superior thermo-mechanical properties. Glass FRPs (GFRPs) have emerged as one of the best alternatives in the field of civil infrastructure. It has been more than four decades since fiber reinforced polymer (FRP) composites have gained notable applications in civil infrastructure industry. However, FRPs have …

Fully Compressible Hydrodynamic Simulation Of Non-Equidiffusive Premixed Flames Propagation In Channels, Olatunde A. Abidakun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Premixed combustion remains of fundamental interest in energy generation and propulsion systems as well as in implementation of safety measures for residential and industrial accidental fire explosions. While the fast pace and complex nature of the combustion process has previously necessitated the analytical and computational studies to employ the simplifying assumption of equidiffusivity, when the Lewis number defined as the thermal-to-mass diffusivities ratio is unity , the ongoing advancements in technology and the requirements for efficiently operating combustors over a wide range of conditions make the combustion process more non-equdiffusive ( ) than ever. The impact of non-equidiffusivity on the …

Evaluating The Polishing Of Skid Aggregates In Asphalt Using The British Pendulum Tester, Allison Nicole Givens

Graduate Theses, Dissertations, and Problem Reports (ETD)

To ensure the pavements in West Virginia have adequate skid resistance the Division of Highways evaluates and approves skid resistant aggregate sources for all wearing courses on roads with an ADT of 3,000 or greater. Unfortunately, the supply of skid aggregates in West Virginia is depleting quickly. To find a potential alternative to using skid resistant aggregates, laboratory polishing of asphalt samples was performed using a Circular Track Polishing Machine, and friction was tested using a British Pendulum Tester. The experiment was designed to investigate how a specific aggregate type provides skid resistance to a hot asphalt mixture.

The objective …