Digital Commons Network^™

Applying Radom Forest And Support Vector Machine For Land-Use Classification In Phu Giao District Vietnam, Trong Dieu Hien Le, Linh Truong Vinh

Applied Environmental Research

Machine learning algorithms are currently widely used to classify satellite images to create surface maps of the earth. Support vector machines (SVMs) and random forests (RFs) are more effective ML algorithms and more accurate classifications than other methods. The aim of this study is to analyze the performance of these two algorithms in land-use and land cover classification. For this purpose, the Landsat 8 OLI satellite image freely provided by the United States Geological Survey (USGS) was used to classify land use in the Phu Giao District, Binh Duong Province, Vietnam, where forestland is being strongly converted into rubber plantations …

Effects Of Herbicides On 2,4-D-Resistant Soil Microorganisms In Maize Cultivation In Lopburi Province, Thailand, Boontarik Chimchart, Jitra Kokaew, Amnat Eamvijarn, Kanokon Bunpha, Sontaya Khamtib, Monchai Manassila, Tawatchai Inboonchuay

Applied Environmental Research

This study aimed to assess the impact of herbicide application on soil micro-organism density and to identify microorganisms resistant to 2,4-D-dimethyl-ammonium (2,4-D) for potential biodegradation. Research was conducted in maize plots in Lopburi Province, where 2,4-D was applied at a rate of 120 g of active ingredient per 160 m2. The soil samples were collected at various intervals: before application; 2 and 4 hours postapplication; and 1, 3, and 7 days after application. The analyses included soil property and microorganism population analyses. The results indicated that 2,4-D applications significantly increased bacteria and fungi in the treated plots compared with those …

Kinetics Of Hexavalent Chromium Adsorption And Reduction By Living Cells Of The Marine Bacterium Bacillus Cereus, Jittima Charoenpanich, Wachiraphorn Cherdchoo, Jutamas Pantab, Jariya Supakrit

Applied Environmental Research

This study identified Bacillus cereus, an efficient Cr(VI) bioreducer, isolated from marine sediment in Thailand. Batch experiments verified the complete removal of 25 mg L-1Cr(VI) from synthetic wastewater (pH 7.0) after 6 days at 37 °C, 50 rpm,and a biomass concentration of 25% (v/v) culture inoculum. The Freundlich isotherm model demonstrated the best correlation with the Cr(VI) adsorption equilibrium data in the 25–100 mg L-1concentration range (R2= 0.9831). Kinetic analyses indicated that the removal of Cr(VI) by living B. cereusfollowed a pseudo-second-order adsorption model (R2= 0.9875) and a pseudo-second-order reduction model (R2= 0.9807). The adsorption rate can be accuratelycharacterizedvia the …

Government Support And Local Residents’ Behavior In E-Waste Management: Evidence From Thailand, Peeranart Kiddee, Somsiri Decharat, Suttiporn Bunmak

Applied Environmental Research

Electronic waste (e-waste) management is a critical global pollution concern. This study investigates government support; local residents' perceptions, knowledge, attitudes, and behaviors related to e-waste management; and collaborative governance in southern Thailand. Employing both quantitative and qualitative methods, this research involves expert government officers who are well versed in e-waste management and local residents. The study utilized in-depth interviews, questionnaires, and workshops. The results revealed that the government is responsible for four e-waste management approaches, encompassing various e-waste collection, transportation, and disposal methods. Local residents exhibited low perceptions of e-waste news but possessed substantial knowledge and positive attitudes toward e-waste …

Landslide Susceptibility Mapping Via Dempster-Shafer, Statistical Index, And Certainty Factor Models In Gis And Their Comparison At Pidie Recency In Aceh, Indonesia, Septianto Aldiansyah, Amniar Ati, Fitriyani Saudi

Applied Environmental Research

Landslides are natural disasters that are active if there is an interaction of environmental factors that are considered to control them, especially in mountainous areas. This study developed a landslide susceptibility map in Pidie Regency via the Dempster-Shafer (DS), statistical index (SI), and certainty factor (CF) models. A total of 957 landslide events were mapped, 70% of which were used for modeling, whereas the remaining events were used to validate the model output. Fourteen layers of conditioning factors were used: elevation, slope, aspect, curvature, TWI, SPI, STI, NDVI, rainfall, distance from river, distance from road, distance from fault, LULC, and …

Assessment Of Landslide Susceptibility And Settlement Exposure Via Geospatial Techniques In Bulambuli Distrcit, Eastern Uganda, Andrew Mulabbi, John Calvin Esagu, Gertrude Akello, Remigio Turyahabwe

Applied Environmental Research

Landslide susceptibility is a significant concern in Elgon County, Uganda, particularly during the rainy season. This vulnerability is attributable to several factors, including steep slopes, fertile soils, and dense settlements on volcanic ridges. Landslide susceptibility maps are important in mitigating the risk particularly at the local level. The objectives of this study were 1) to model landslide susceptibility via an interpretable machine-learning model, 2) to identify the most influential factors for landslide susceptibility in the study area, and 3) to assess the exposure of settlements to landslide risk. This study employed the XGBoost model trained on nine conditioning factors via …

Exploration Of Indigeneous Biosurfactant-Producing Bacillus Sp. From Petroleum Hydrocarbon-Contaminated Soil In Indonesia, Rizky Danang Susetyo, Wahyu Wilopo, Suwarno Hadisusanto, Endah Retnaningrum

Applied Environmental Research

Hydrocarbonolastic bacteria are valuable for the remediation of petroleum-polluted environments. The production of biosurfactants by such bacteria significantly enhances hydrocarbon bioavailability and increases remediation efficiency. One genus of hydrocarbonolastic bacteria with the potential to produce biosurfactants is Bacillus, yet strain-level diversity and local adaptations remain underexplored.Tthis study aimed to isolate and characterize hydrocarbonolastic bacteria belonging to the Bacillus genus from soil samples collected at Geopetroleum Teksas Wonocolo, Kedewan District, Bojonegoro Regency, Indonesia, which is a historically underreported hydrocarbon site. Additionally, the capacity of Bacillus to synthesize biosurfactants was examined. Bacillus strains capable of biosur-factant production were identified via a polyphasic …

Design And Comparative Analysis Of Electric Motors With “Flux-Switching” Effect Having Reluctance Rotors And Pm Or Dc Stator Excitation, Oluwaseun A. Badewa, Ali Mohammadi, Donovin D. Lewis, Somasundaram Essakiappan, Madhav Manjrekar, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper introduces innovative designs for synchronous electric motors with phase coils and permanent magnets (PM) or DC-excitation coils embedded in the stator. Alongside concentrated phase coils in dedicated slots, the spoke-type PMs offer high flux intensification, while the option for DC-excitation coils eliminates demagnetization risks. Since the rotor has no active electromagnetic components, the machine can achieve high-speed operation while enabling advanced cooling systems focused solely on the stator. A special implementation with a “wave” or “serpentine” DC-excitation winding which has the potential for reduced losses depending on the motor aspect ratio is presented. The operation, control, and polarity …

Harmonic And Non-Linear Effects On The Parameters And Performance Of A Vernier Machine With Flux Concentrating Spoke Rotor, Ali Mohammadi, Yaser Chulaee, Aaron M. Cramer, Ion G. Boldea, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents a systematic study on the MAGNUS machine, which is an innovative dual-stator axial flux permanent magnet vernier machine (AFPMVM). The MAGNUS machine features a novel single-wound dual-stator design with minimal slots and an exceptionally high-polarity spoke-type permanent magnet rotor, which enables a very high flux concentration ratio. The operating principle of vernier machines is derived, showing the possible slot-pole combinations. Inductance components are introduced, and multiple methods are employed to determine the direct and quadrature axis inductances, revealing that despite its spoke-type rotor, due to a high harmonic content and a high differential leakage inductance, the MAGNUS …

Drone Medical Package Delivery For Improved Transportation And Better Patient Outcomes Final Implementation Report, Amro El-Adle, Madeline Alden, Yin-Hsuen Chen, Melissa Davidson

Information Technology & Decision Sciences Faculty Publications

The Drone Medical Package Delivery for Improved Transportation and Better Patient Outcomes planning and prototyping grant involves five partners, including Accomack-Northampton Planning District Commission (A-NPDC), Riverside Health System, Old Dominion University (ODU), Virginia Institute for Spaceflight & Autonomy (VISA), Virginia Innovation Partnership Corporation (VIPC), and DroneUp. The partners worked together to address access, safety, reliability and sustainability for medical and emergency response package delivery via drone, specifically, where the use of aerial drones could lead to better patient outcomes and improved safety and emergency response.

The goal of the project was to develop an operational prototype that woul evolve into …

Comparing Funders' Altruism Versus Self-Interest: Leveraging The Context Of Crisis, Dan Liu, Guangzhi Shang, Cynthia Fan Yang

Journal of International Technology and Information Management

While reward-based crowdfunding has widespread popularity, the motivations driving funders, balancing self-interest and altruism, have remained puzzling. Prior research has been constrained by examination methods and produced mixed findings regarding the weight of altruism versus self-interest among funders. Our study takes a fresh perspective, delving into funder behavior amid a major crisis—the tumultuous backdrop of the COVID-19 pandemic. Our findings reveal that funders not only display an increased willingness to contribute but also significantly amplify their contributions, particularly to projects in crisis-affected regions, irrespective of external incentives like rewards. This underscores the prevalence of altruistic motives among funders in challenging …

Understanding The Determinants Of Blockchain Adoption: An Empirical Study, Amarpreet Kohli, Nihar Kumthekar, Piyush Shah, Rebecca Jauch

Journal of International Technology and Information Management

Blockchain technology (BT) has the potential to enhance security and robustness of transactions through a distributed ledger bookkeeping process. This study employs technology-organization-environment (TOE) framework and threat-rigidity theory (TRT) to examine whether perceived disruption caused by COVID-19 pandemic significantly impacted the adoption of BT, and inclination to adopt BT in the US. The COVID-19 pandemic provided a unique backdrop, as it affected businesses across all industries, sizes, and geographies. Results show a non-significant effect of perceived pandemic disruption on the current stage of BT adoption and intention to adopt BT. However, disruption readiness positively influences the current stage of BT …

Comparing Vr And Tv In Nigeria And The U.S.: Impacts On Empathy, Engagement, And Enjoyment, Jinhee Yoo, Eugene A. Ohu, Radosław Mącik

Journal of International Technology and Information Management

This study (N = 170), involving participants from Nigeria and the U.S., investigated how different technologies (TV and VR) affect users' empathy (α = .93), engagement (α = .93), enjoyment (α = .93), preferences, and likelihood of technology use. Participants watched an animated documentary titled “Is Anna OK?” at two different time points, utilizing VR (Oculus Rift S) and TV, following which they completed measuring empathy, engagement, enjoyment, device preference, and usage likelihood. Analysis via one-way ANOVA and chi-square tests revealed that VR users reported significantly higher empathy and enjoyment compared to TV viewers, particularly on second viewing. Combining both …

The Effect Of Liquid Conductivity On A Helium Plasma Jet And The Hydrogen Peroxide Production, Edwin A. Oshin, M. Ziaur Rahman, Chunqi Jiang

Bioelectrics Publications

Understanding plasma-liquid interactions and the impact of the electrical conductivity (σ) of liquid on plasma is important for plasma applications in water treatment and medicine. Ultrapure water, phosphate-buffered saline (PBS) solution, biological media, and sodium chloride (NaCl) solutions at various concentrations were used in this study to provide a broad range of conductivity values ranging from 0.055 μS cm⁻¹ to 222 mS cm⁻¹. A helium atmospheric pressure plasma jet (APPJ) impinging on liquid was generated in ambient air using a hollow-needle electrode that was powered by 200 ns, 7 kV pulses at a pulse repetition frequency of …

Human Perception Of Ai Capabilities At Classifying Perturbed Roadway Signs, Katherine R. Garcia, Jing Chen, Yanru Xiao, Scott Mishler, Cong Wang, Bin Hu

Psychology Faculty Publications

Artificial Intelligence (AI) is crucial to numerous functions required for driving automation systems, including the computer vision techniques used to detect the roadway environment and make real-time decisions. However, the images used as inputs to the AI system may be maliciously perturbed, or manipulated, causing the AI system to make an incorrect classification. In this study, we examined humans’ perception of the AI’s computer vision capability of classifying various road sign images, including the original images, images with two different types of malicious attacks, and images that are scrambled randomly at the pixel level. Our results showed that participants rated …

Food Waste Crisis In The United States Of America: The Known, The Overlooked And The Undisclosed, Sagarika Srivastava, David J. Tonjes

Technology & Society Faculty Publications

With a loss of 1,250 calories per day per person or 140 kg/p/yr, the United States (U.S.) has a large problem with food waste. The later a product is wasted in the supply chain, the greater its environmental cost. Many food waste mitigation efforts focus on the retail and consumer stages, but there is also considerable food waste in the production phase, which includes growing, harvesting, transportation, storage and processing. The study is conducted in two steps: a bibliometric analysis of 218 articles on food waste in the U.S., followed by an investigation of options to meet food waste recovery …

Salinity Effects On Cu(Ii) Bioremediation By Chlamydomonas Reinhardtii Microalgae, Jennifer Hughes

Honors Undergraduate Theses

Microalgae offer a sustainable approach to wastewater treatment by removing pollutants such as excess nutrients, CO₂, and heavy metals. Among various species, Chlamydomonas reinhardtii shows strong potential in removing Cu(II) ions from wastewater. In addition, salinity stress in C. reinhardtii has been linked to morphological and metabolic changes that enhance lipid and phytochemical production. While salinity stress has been studied for enhancing biofuel production, its impact on microalgal removal of heavy metals, particularly Cu(II), remains largely unexplored. Understanding how varying salinity conditions affect both algal growth and the efficiency of Cu(II) remediation could provide critical insights for improving integrated wastewater …

Traction Force Microscopy Using An Epifluorescence Microscope: Experimental Considerations And Caveats, Zaria Booth, Mazen Mezher, Rudra Patel, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Forces exerted by cells due to their internal contractility play fundamental roles in a host of processes, including adhesion, migration, survival and differentiation. Traction force microscopy (TFM) enables the determination of forces exerted by cells or cell collectives on their environment, which is typically taken to be an extra-cellular matrix (ECM)-coated substrate. Sample preparation for TFM involves the plating of cells onto an environment embedded with fiducial markers. The imaging of these fiducial markers in the presence and absence of the cells then enables calculation of the displacement of localized regions of the environment, and, consequently, the spatial distribution of …

Flexural Strength Of (Hf,Nb,Ta,Ti,Zr)B2–(Hf,Nb,Ta,Ti,Zr)C High-Entropy Dual-Phase Ceramics, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas, Jeremy Watts

Materials Science and Engineering Faculty Research & Creative Works

The room and elevated temperature flexural strengths were measured for (Hf,Nb,Ta,Ti,Zr)B2–(Hf,Nb,Ta,Ti,Zr)C high-entropy dual-phase ceramics. The fracture of ceramics originated from two distinct flaw populations that were either surface defects introduced during specimen preparation or volume defects introduced during processing. The average strength at room temperature was 638 ± 94 MPa with individual bars strengths as high as ∼800 MPa. At 1800°C, average strength increased to 786 ± 265 MPa with individual bar strengths as high as ∼1050 MPa. Above 1800°C, creep dominated resulting in deformation of the bars without fracture. The fracture mode changed from completely trans granular at room …

Optimization Of Persulfate Activation System Using Ferrous Sulfate For Toc Removal From Real Domestic Wastewater, Mohamed Fouad, Mohamed Mossad, Mohamed Gar Alalm, Mahmoud Samy

Mansoura Engineering Journal

The reuse of treated wastewater is increasingly recognized as a sustainable solution to address global water shortage. This study investigates the effectiveness of a persulfate-based advanced oxidation process (AOP) using sodium persulfate (Na2S2O8) activated by ferrous sulfate (FeSO4) as a tertiary treatment for secondary effluents. Real municipal wastewater was collected from Agouzain Wastewater Treatment Plant (WWTP) in Kafr El-Sheikh, Egypt. A Box Benkhen design (BBD) was employed to optimize three key variables: FeSO4 dose (0.5–2.0 g/L), Na2S2O8 dose (0.5–2.0 g/L), and pH (3.0–9.0), with total organic carbon (TOC) removal as the main response. Under optimized conditions (0.50 g/L FeSO4, 2.00 …

Introducing Sustainable Development Goals In College Curricula: A Way Forward, Christy Ashley, Jason D. Oliver, Hillary Leonard

Markets, Globalization & Development Review

The commentary proposes a blueprint to help guide curriculum innovations, partnerships, and teaching interventions that incorporate the United Nations sustainable development goals (SDGs) into the curriculum. It suggests the utilization of AACSB’s Societal Impact Canvas with Ancona et al.’s (2007) Leadership Capabilities (Sensemaking, Relating, Visioning, Inventing) to provide a blueprint for mission-aligned SDG integration at a local level. It provides an illustrative example from the University of Rhode Island (USA), where the focus is on the Blue Economy. It aims to provide practical guidance for how a college or university can efficiently organize to gain stakeholder input that helps enhance …

Axial Flux Permanent Magnet Generators For Direct-Drive Wind Turbines - Review And Optimal Design Studies, Matin Vatani, Ali Mohammadi, Donovin D. Lewis, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents a comprehensive analysis of the feasibility, cost, and electromagnetic performance of five distinct types of axial flux permanent magnet (AFPM) generators designed for direct-drive wind turbines. The generator configurations investigated include a single-sided AFPM generator with a surface-mounted PM rotor (AFPMG), a double-sided AFPM generator featuring PMs on the stator and a reluctance rotor (AFPMG-RR), a coreless stator AFPM generator with surface PMs (CAFPMG-SPM), and a coreless stator AFPM generator with a Halbach PM array rotor (CAFPMG-Hal). Each generator’s operating principles and configurations are thoroughly explained and compared. Large-scale multi-objective design optimizations were conducted on each type, …

Review Of Coreless Axial Flux Permanent Magnet Machines With Applications Including Electric Aircraft Propulsion, Matin Vatani, Donovin D. Lewis, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Axial flux permanent magnet (AFPM) machines with entirely or stator coreless configurations offer significant advantages, including low rotational losses, the absence of cogging torque, minimal torque ripple, and the potential for high specific power density. Advances in permanent magnet (PM) technology and cooling techniques have enabled fully coreless AFPM machines to achieve high magnetic and current loadings without core saturation, making them suitable for high performance applications like electric aircraft propulsion. This paper reviews recent advancements in coreless AFPM machines, tracing their historical and chronological development. Various topologies, including single- and double-sided and multi-disk designs, are examined to identify the …

Speed Variation Based Power Regulation Concept For Dynamic Wireless Charging, Donovin D. Lewis, Sudarshan T. Harave, Omer Onar, Mostak Mohammad, Veda Prakash Galigekere, Gui-Jia Su, Dan Ionel

Electrical and Computer Engineering Graduate Research

On-road wireless charging of electric vehicles (EVs) in-motion could potentially reduce range anxiety or battery size with wide-spread deployment. The planning and implementation of such systems are greatly complicated due to their susceptibility to load variation inherent to traffic flow. This paper proposes a method for derisking the potential for traffic slowdowns by compensating for reduced vehicle speed and investigates how implementation may affect system performance. A load modeling case study is presented at 200kW for a mile of high-speed roadway employing speed-based power regulation with results indicating average power usage and maximum car hosting capability can be reduced by …

Fault-Tolerant High-Power Two-Phase Coreless Afpm Motor-Drive System Concept, Yaser Chulaee, Ali Mohammadi, Matin Vatani, Aaron M. Cramer, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper proposes a fault-tolerant, high-power two-phase coreless axial flux permanent magnet (AFPM) motor drive system concept. Initially, the performance of a two-phase variant of the coreless AFPM machine is compared with that of its three-phase counterpart using both 3D finite element analysis (FEA) and experiments. Thanks to the intrinsic unique features of coreless AFPM machines, the analysis of the results demonstrates that the two-phase configuration has comparable power density (kW/kg) and efficiency. In terms of fault tolerance, the two-phase configuration exhibits superior performance, as the mutual inductance between phases is zero, resulting in an electric machine with magnetically decoupled …

Two-Level Multi-Objective Design Optimization Including Torque Ripple Minimization For Stator Excited Synchronous And Flux Switching Machines, Ali Mohammadi, Oluwaseun A. Badewa, Yaser Chulaee, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Electric machine performance can be enhanced through torque ripple mitigation, which reduces mechanical vibrations and improves system stability and operation. This paper proposes a novel two-level optimization method for synchronous flux-switching and hybrid excitation machines, featuring an innovative multi-point spline shaping approach for torque ripple minimization. The study employs experimentally validated models based on a prototype with a similar topology. The optimization process is implemented on two distinct designs: a 20-pole inner rotor PM-excited stator machine and a 28-pole outer rotor DC-excited stator machine. Analysis results demonstrate that the proposed innovative method significantly reduces torque ripple in both configurations. Force …

Electromagnetic Design Characterization Of Synchronous Machines With Flux Switching Effect Employing Reluctance Rotors And Stators With Pms And Ac Concentrated Coils, Oluwaseun A. Badewa, Ali Mohammadi, Donovin D. Lewis, Somasundaram Essakiappan, Madhav Manjrekar, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper introduces an innovative design for a synchronous electric motor that has phase coils and permanent magnets (PM) embedded in the stator. The electric machine contains both concentrated winded phase coils in dedicated slots and spoke-type permanent magnets solely in the stator. The spoke-type magnet arrangement achieves a high flux intensity even with low remanence non-rare earth permanent magnets. As the rotor has no active electromagnetic components, the risk for demagnetization is reduced and advanced cooling applied to the stator can enable high-speed operation. The principle of operation and polarity of the motor are investigated with a unique approach …

Adaptation For Whom? Understanding The Impacts Of Dyke Policies On Small-Scale Farmers In Ca Mau Province Of Vietnam, Nguyen Minh Quang, Nguyen Van Minh, Nguyen Vo Chau Ngan, Martha B. Lerski

Publications and Research

Low-lying deltas worldwide are extremely vulnerable to sea-level rise. As the risks of climate-induced flooding become increasingly clear, the thirst for infrastructure-driven adaptation increases. This highlights a patent need to understand the impacts of engineering adaptation solutions, especially those targeting built structures such as dykes and sluices, on farmers from a bottom-up, farmer-centred perspective. The study addresses this call by examining cases where dyke policies, while successful in some dimensions, have undermined small-scale farmer livelihoods in Ca Mau ― Vietnam’s southernmost rural province. It identifies areas in need of attention and adds empirical data related to this group of farmers. …

Smartphones On Wheels In Southeast Asia: A Crossroads For Data Governance, Attamongkol Tantratian, Gunn Jiravuttipong

Journal of Law and Mobility

While the transformation of automobiles into data-generating “smartphones on wheels” has revolutionized mobility, it has also raised critical concerns over data privacy and sovereignty. Equipped with sensors and connected technologies, smart vehicles collect vast amounts of data, including personal information, driving patterns, and biometric identifiers. While auto-exporting jurisdictions such as the United States, the European Union, and China have introduced regulatory measures to address these challenges, countries importing smart vehicles remain vulnerable due to their limited influence over the auto companies’ integrated technology and data policies.

This Article examines the regulatory and economic challenges faced by developing nations integrating foreign-designed …

The Design Of A Bioinspired Impact Mitigation System Towards The Prevention Of Brain Injuries, Bryce H. Reimer

Master’s Theses

Traumatic brain injuries (TBIs), including concussions and chronic traumatic encephalopathy (CTE), remain a major concern across contact sports, military operations, and transportation. Despite advancements in protective equipment, current strategies often fall short in preventing the mechanical conditions that contribute to long-term neurological damage. This thesis presents the design and validation of a bioinspired impact mitigation system modeled after bighorn sheep horn structures, which have evolved to endure high-energy collisions without apparent brain injury.

Using biomimetic principles, the research integrates experimental and computational methods to evaluate how horn-like geometries reduce impact-induced accelerations. A custom drop tower was built to test dynamic …