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2022

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Full-Text Articles in Engineering

Design And Performance Analysis Of A Chemically-Etched Flexible Nfc Tag Antenna, Muhammad Enayetur Rahman, Marwan Abdelatti, Manbir Singh Sodhi, Kunal Mankodiya Jan 2022

Design And Performance Analysis Of A Chemically-Etched Flexible Nfc Tag Antenna, Muhammad Enayetur Rahman, Marwan Abdelatti, Manbir Singh Sodhi, Kunal Mankodiya

Electrical & Computer Engineering Faculty Publications

Near Field Communication (NFC) is a perfect example of ubiquitous computing that is secured, short-ranged, low-powered contactless communication. High demand is predicted for NFC, especially with wearables, and the variety of applications may require that this technology be fabricated onto different materials. In this research, we first designed flexible NFC antennas based on mathematical models. A simulation of the NFC coil inductance was performed and verified using the predictive models. Later, two flexible NFC antennas, including 160x80 mm2 (rectangular) and 80x80 mm2 (square) were fabricated through a chemical etching process and verified at 13.56 MHz frequency. Two experiments 1) Read …


Reducing Print Time While Minimizing Loss In Mechanical Properties In Consumer Fdm Parts, Long Le, Mitchel A. Rabsatt, Hamid Eisazadeh, Mona Torabizadeh Jan 2022

Reducing Print Time While Minimizing Loss In Mechanical Properties In Consumer Fdm Parts, Long Le, Mitchel A. Rabsatt, Hamid Eisazadeh, Mona Torabizadeh

Mechanical & Aerospace Engineering Faculty Publications

Fused deposition modeling (FDM), one of various additive manufacturing (AM) technologies, offers a useful and accessible tool for prototyping and manufacturing small volume functional parts. Polylactic acid (PLA) is among the commonly used materials for this process. This study explores the mechanical properties and print time of additively manufactured PLA with consideration to various process parameters. The objective of this study is to optimize the process parameters for the fastest print time possible while minimizing the loss in ultimate strength. Design of experiments (DOE) was employed using a split-plot design with five factors. Analysis of variance (ANOVA) was employed to …


Radiomic Texture Feature Descriptor To Distinguish Recurrent Brain Tumor From Radiation Necrosis Using Multimodal Mri, M. S. Sadique, A. Temtam, E. Lappinen, K. M. Iftekharuddin Jan 2022

Radiomic Texture Feature Descriptor To Distinguish Recurrent Brain Tumor From Radiation Necrosis Using Multimodal Mri, M. S. Sadique, A. Temtam, E. Lappinen, K. M. Iftekharuddin

Electrical & Computer Engineering Faculty Publications

Despite multimodal aggressive treatment with chemo-radiation-therapy, and surgical resection, Glioblastoma Multiforme (GBM) may recur which is known as recurrent brain tumor (rBT), There are several instances where benign and malignant pathologies might appear very similar on radiographic imaging. One such illustration is radiation necrosis (RN) (a moderately benign impact of radiation treatment) which are visually almost indistinguishable from rBT on structural magnetic resonance imaging (MRI). There is hence a need for identification of reliable non-invasive quantitative measurements on routinely acquired brain MRI scans: pre-contrast T1-weighted (T1), post-contrast T1-weighted (T1Gd), T2-weighted (T2), and T2 Fluid Attenuated Inversion Recovery (FLAIR) that can …


Broadband Dielectric Spectroscopic Detection Of Ethanol: A Side-By-Side Comparison Of Zno And Hkust-1 Mofs As Sensing Media, Papa K. Amoah, Zeinab Mohammed Hassan, Pengtao Lin, Engelbert Redel, Helmut Baumgart, Yaw S. Obeng Jan 2022

Broadband Dielectric Spectroscopic Detection Of Ethanol: A Side-By-Side Comparison Of Zno And Hkust-1 Mofs As Sensing Media, Papa K. Amoah, Zeinab Mohammed Hassan, Pengtao Lin, Engelbert Redel, Helmut Baumgart, Yaw S. Obeng

Electrical & Computer Engineering Faculty Publications

The most common gas sensors are based on chemically induced changes in electrical resistivity and necessarily involve making imperfect electrical contacts to the sensing materials, which introduce errors into the measurements. We leverage thermal- and chemical-induced changes in microwave propagation characteristics (i.e., S-parameters) to compare ZnO and surface-anchored metal-organic-framework (HKUST-1 MOF) thin films as sensing materials for detecting ethanol vapor, a typical volatile organic compound (VOC), at low temperatures. We show that the microwave propagation technique can detect ethanol at relatively low temperatures (<100 >°C), and afford new mechanistic insights that are inaccessible with the traditional dc-resistance-based measurements. In addition, …


Precursors Of Email Response To Cybersecurity Scenarios: Factor Exploration And Scale Development, Miguel A. Toro-Jarrin, Pilar Pazos-Lago, Miguel Padilla Jan 2022

Precursors Of Email Response To Cybersecurity Scenarios: Factor Exploration And Scale Development, Miguel A. Toro-Jarrin, Pilar Pazos-Lago, Miguel Padilla

Engineering Management & Systems Engineering Faculty Publications

In the last decade, information security research has further expanded to include human factors as key elements of the organization's cybersecurity infrastructure. Numerous factors from several theories have been explored to explain and predict the multitude of information security-related behaviors in organizations. Lately, there has been a call for the study of specific cybersecurity behaviors in contextualized scenarios that reflect specific and realistic situations of a potential cyber-attack. This paper focuses on precursors of email response in situations that can be the origin of cybersecurity incidents in organizations (i.e., phishing attacks, ransomware, etc.). This study explores participants' intentions to follow …


Grounding Evaluation Capacity Development In Systems Theory, Sarah D. Klier, Raphael J. Nawrotzki, Nataly Salas-Rodríguez, Sven Harten, Charles B. Keating, Polinpapilinho F. Katina Jan 2022

Grounding Evaluation Capacity Development In Systems Theory, Sarah D. Klier, Raphael J. Nawrotzki, Nataly Salas-Rodríguez, Sven Harten, Charles B. Keating, Polinpapilinho F. Katina

Engineering Management & Systems Engineering Faculty Publications

While “systemic thinking” is popular in the context of capacity development and evaluation, there is currently a lack of understanding about the benefits to employing systems theory in evaluation capacity development. Systems theory provides a useful orientation to the work involved in complex systems (e.g. national evaluation systems). This article illustrates how evaluation capacity development practitioners can use systems theory as a conceptual tool to gain a better understanding of the functional aspects and interrelationships present within a given evaluation system. Specifically, the systems theory perspective can help elucidate the reasons for the success or failure of a given evaluation …


A Human Factors Study Of Risk Management Of Complex Agile Scrum Projects In Large Enterprises, Ravi Kalluri Jan 2022

A Human Factors Study Of Risk Management Of Complex Agile Scrum Projects In Large Enterprises, Ravi Kalluri

Engineering Management & Systems Engineering Faculty Publications

Agile Project Management methods have gained phenomenal success in the IT software world in managing projects of high complexity and uncertainty. However, Agile projects come with their unique set of risks. This paper seeks to explore the risks posed by human factors to complex Agile Scrum projects in large enterprises. Project Risk Management is crucial in determining the future performance of a complex project. Increasing project complexity makes it more and more difficult to anticipate potential events that could affect the project and to make effective decisions to reduce project risk exposure. This is even more true for Agile projects …


On The Implementation And Further Validation Of A Time Domain Boundary Element Method Broadband Impedance Boundary Condition, Fang Q. Hu, Douglas M. Nark Jan 2022

On The Implementation And Further Validation Of A Time Domain Boundary Element Method Broadband Impedance Boundary Condition, Fang Q. Hu, Douglas M. Nark

Mathematics & Statistics Faculty Publications

A time domain boundary integral equation with Burton-Miller reformulation is presented for acoustic scattering by surfaces with liners in a uniform mean flow. The Ingard-Myers impedance boundary condition is implemented using a broadband multipole impedance model and converted into time domain differential equations to augment the boundary integral equation. The coupled integral-differential equations are solved numerically by a March-On-in-Time (MOT) scheme. While the Ingard-Myers condition is known to support Kelvin-Helmholtz instability due to its use of a vortex sheet interface between the flow and the liner surface, it is found that by neglecting a second derivative term in the current …


Type-B Energetic Processes And Their Associated Scientific Implications, James Weifu Lee Jan 2022

Type-B Energetic Processes And Their Associated Scientific Implications, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Recently, our work has identified two thermodynamically distinct types (A and B) of energetic processes naturally occurring on Earth. Type-A energy processes such as the classical heat engines, ATP hydrolysis, and many of the known chemical, electrical, and mechanical processes apparently follow well the second law of thermodynamics; Type-B energy processes, for example, the newly discovered thermotropic function that isothermally utilizes environmental heat energy to do useful work in driving ATP synthesis, follow the first law of thermodynamics (conservation of mass and energy) but do not have to be constrained by the second law, owing to its special asymmetric functions. …


Ozonized Biochar Filtrate Effects On The Growth Of Pseudomonas Putida And Cyanobacteria Synechococcus Elongatus Pcc 7942, Oumar Sacko, Nancy L. Engle, Timothy J. Tschaplinski, Sandeep Kumar, James Weifu Lee Jan 2022

Ozonized Biochar Filtrate Effects On The Growth Of Pseudomonas Putida And Cyanobacteria Synechococcus Elongatus Pcc 7942, Oumar Sacko, Nancy L. Engle, Timothy J. Tschaplinski, Sandeep Kumar, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Background

Biochar ozonization was previously shown to dramatically increase its cation exchange capacity, thus improving its nutrient retention capacity. The potential soil application of ozonized biochar warrants the need for a toxicity study that investigates its effects on microorganisms.

Results

In the study presented here, we found that the filtrates collected from ozonized pine 400 biochar and ozonized rogue biochar did not have any inhibitory effects on the soil environmental bacteria Pseudomonas putida, even at high dissolved organic carbon (DOC) concentrations of 300 ppm. However, the growth of Synechococcus elongatus PCC 7942 was inhibited by the ozonized biochar filtrates at …


The Hitran2020 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, R. J. Hargreaves, R. Hashemi, E. V. Karlovets, F. M. Skinner, E. K. Conway, C. Hill, R. V. Kochanov, Y. Tan, P. Wcisło, A.A. Finenko, K. Nelson, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance, A. Coustenis, B. J. Drouin, J.-M. Flaud, R. R. Gamache, J. T. Hodges, D. Jacquemart, E. J. Mlawer, A. V. Nikitin, V.I. Perevalov, M. Rotger, J. Tennyson, G. C. Toon, H. Tran, V. G. Tyuterev, E. M. Adkins, A. Baker, A. Barbe, E. Canè, A. G. Császár, A. Dudaryonok, O. Egorov, A. J. Fleisher, H. Fleurbaey, A. Foltynowicz, T. Furtenbacher, J. J. Harrison, J.M. Hartmann, V.- M. Horneman, X. Huang, T. Karman, J. Karns, S. Kassi, I. Kleiner, V. Kofman, F. Kwabia-Tchana, N.N. Lavrentieva, T. J. Lee, D. A. Long, A. A. Lukashevskaya, O. M. Lyulin, V. Yu Makhnev, W. Matt, S. T. Massie, M. Melosso, S. N. Mikhailenko, D. Mondelain, H.S.P. Müller, O. V. Naumenko, A. Perrin, O. L. Polyansky, E. Raddaoui, P. L. Raston, Z. D. Reed, M. Rey, C. Richard, R. Tóbiás, I. Sadiek, D. W. Schwenke, E. Starikova, K. Sung, F. Tamassia, S. A. Tashkun, J. Vander Auwera, I.A. Vasilenko, A.A. Vigasin, G.L. Villanueva, B. Vispoel, G. Wagner, A. Yachmenev, S. N. Yurchenko Jan 2022

The Hitran2020 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, R. J. Hargreaves, R. Hashemi, E. V. Karlovets, F. M. Skinner, E. K. Conway, C. Hill, R. V. Kochanov, Y. Tan, P. Wcisło, A.A. Finenko, K. Nelson, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance, A. Coustenis, B. J. Drouin, J.-M. Flaud, R. R. Gamache, J. T. Hodges, D. Jacquemart, E. J. Mlawer, A. V. Nikitin, V.I. Perevalov, M. Rotger, J. Tennyson, G. C. Toon, H. Tran, V. G. Tyuterev, E. M. Adkins, A. Baker, A. Barbe, E. Canè, A. G. Császár, A. Dudaryonok, O. Egorov, A. J. Fleisher, H. Fleurbaey, A. Foltynowicz, T. Furtenbacher, J. J. Harrison, J.M. Hartmann, V.- M. Horneman, X. Huang, T. Karman, J. Karns, S. Kassi, I. Kleiner, V. Kofman, F. Kwabia-Tchana, N.N. Lavrentieva, T. J. Lee, D. A. Long, A. A. Lukashevskaya, O. M. Lyulin, V. Yu Makhnev, W. Matt, S. T. Massie, M. Melosso, S. N. Mikhailenko, D. Mondelain, H.S.P. Müller, O. V. Naumenko, A. Perrin, O. L. Polyansky, E. Raddaoui, P. L. Raston, Z. D. Reed, M. Rey, C. Richard, R. Tóbiás, I. Sadiek, D. W. Schwenke, E. Starikova, K. Sung, F. Tamassia, S. A. Tashkun, J. Vander Auwera, I.A. Vasilenko, A.A. Vigasin, G.L. Villanueva, B. Vispoel, G. Wagner, A. Yachmenev, S. N. Yurchenko

Chemistry & Biochemistry Faculty Publications

The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. …


Modular Expandable Multiinput Multioutput (Mimo) High Step-Up Transformerless Dc-Dc Converter, Zahra Saadatizadeh, Pedram Chavoshipour Heris, H. Alan Mantooth Jan 2022

Modular Expandable Multiinput Multioutput (Mimo) High Step-Up Transformerless Dc-Dc Converter, Zahra Saadatizadeh, Pedram Chavoshipour Heris, H. Alan Mantooth

Electrical Engineering Faculty Publications and Presentations

In this paper, a Multi-Input Multi-Output (MIMO) high step-up transformerless DC-DC converter is proposed. The proposed converter can expand the number of ports from both input and output terminals. Also, it has a modular structure using voltage multiplier cells (a switch, two diodes, a capacitor, and an inductor). The proposed converter is useful for a wide range of applications and has the merit of interfacing multiple hybrid voltage sources with each other to supply different loads with various voltage levels. All the output voltages of the output ports can be regulated at the same time by tuning separate controlling parameters. …


North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev Jan 2022

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Program: Senior Projects (Public)

The following project report was a study of the North 14th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14th Street and the 14th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …


Teaching Learning Newsletter Vol 2 Issue 1, Sastra Deemed To Be University Jan 2022

Teaching Learning Newsletter Vol 2 Issue 1, Sastra Deemed To Be University

TLC Newsletter

No abstract provided.


Implementation And Usage Of Low-Cost Turbines For Power Generation In Water Networks, Luis Javier Ortiz Osornio Jan 2022

Implementation And Usage Of Low-Cost Turbines For Power Generation In Water Networks, Luis Javier Ortiz Osornio

All Graduate Theses, Dissertations, and Other Capstone Projects

The following APP is part of an investigation and development, carried out to design, and implement a hydroelectric turbine of horizontal axis, in order to generate electrical energy in rural areas, utilizing existing infrastructure or natural waterways such as irrigation canals, piping, rivers and streams. Every industrialized country, as well as, most of the developing nations, have a stake in agriculture and thus access to the infrastructure required for irrigation purposes. Artificial irrigation canals offer advantages such as a clean continuous flow, with the possibility of flow regulation: this together with their vast availability as agricultural infrastructure constitute the main …


Improved Warehouse For Smt Material Management Using Modern Technology Retrieval System And Better Traceability, Ferdinand Mabeya Jan 2022

Improved Warehouse For Smt Material Management Using Modern Technology Retrieval System And Better Traceability, Ferdinand Mabeya

All Graduate Theses, Dissertations, and Other Capstone Projects

Warehouse plays a vital role in the manufacturing and distributing goods from raw material to manufacturer and finally to the end-user. Optimizing warehouse material management will make an impact on productivity, quality, and on-time delivery. My thesis focuses on material management of surface mount (SMT) from suppliers, receiving and inspection, and warehouse to maximize efficiency. With SMT line costing over 2 million, the warehouse material management is improved. Things like cycle count and picking material are much faster. It makes the overall equipment efficiency (OEE) very low. To make this material management process possible, manufacturers must embrace Six Sigma and …


Printed Circuit Board Defect Detection Using Image Processing, Nandeera Kamalaja De Silva Munaweera Tanthirige Jan 2022

Printed Circuit Board Defect Detection Using Image Processing, Nandeera Kamalaja De Silva Munaweera Tanthirige

All Graduate Theses, Dissertations, and Other Capstone Projects

This study was conducted to verify the hypothesis of the possibility to design an Automated Defect Detection system at a budget using image processing software. Focusing mainly on simplicity of integration with the capability to inspect a high variation of PCB with less user input. Reference comparison method was utilized to construct the defect detection algorithm where a defect free reference PCB gets compared with an inspection image to identify defects and anomalies. The paper discusses the range of possible defects for inspection on non-assembled PCBs, suggests methods for image processing and presents a final inspection algorithm, including their testing. …


Investigating How Speech And Animation Realism Influence The Perceived Personality Of Virtual Characters And Agents, Sean A. Thomas, Ylva Ferstl, Rachel Mcdonnell, Cathy Ennis Jan 2022

Investigating How Speech And Animation Realism Influence The Perceived Personality Of Virtual Characters And Agents, Sean A. Thomas, Ylva Ferstl, Rachel Mcdonnell, Cathy Ennis

Articles

The portrayed personality of virtual characters and agents is understood to influence how we perceive and engage with digital applications. Understanding how the features of speech and animation drive portrayed personality allows us to intentionally design characters to be more personalized and engaging. In this study, we use performance capture data of unscripted conversations from a variety of actors to explore the perceptual outcomes associated with the modalities of speech and motion. Specifically, we contrast full performance-driven characters to those portrayed by generated gestures and synthesized speech, analysing how the features of each influence portrayed personality according to the Big …


Importance Measure-Based Maintenance Strategy Considering Maintenance Costs, Chao Zhang, Yadong Zhang, Hongyan Dui, Shaoping Wang, Mileta M. Tomovic Jan 2022

Importance Measure-Based Maintenance Strategy Considering Maintenance Costs, Chao Zhang, Yadong Zhang, Hongyan Dui, Shaoping Wang, Mileta M. Tomovic

Engineering Technology Faculty Publications

Maintenance is an important way to ensure the best performance of repairable systems. This paper considers how to reduce system maintenance cost while ensuring consistent system performance. Due to budget constraints, preventive maintenance (PM) can be done on only some of the system components. Also, different selections of components to be maintained can have markedly different effects on system performance. On the basis of the above issues, this paper proposes an importance-based maintenance priority (IBMP) model to guide the selection of PM components. Then the model is extended to find the degree of correlation between two components to be maintained …


Performance Degradation Based On Importance Change And Application In Dissimilar Redundancy Actuation System, Yadong Zhang, Chao Zhang, Shaoping Wang, Rentong Chen, Mileta M. Tomovic Jan 2022

Performance Degradation Based On Importance Change And Application In Dissimilar Redundancy Actuation System, Yadong Zhang, Chao Zhang, Shaoping Wang, Rentong Chen, Mileta M. Tomovic

Engineering Technology Faculty Publications

The importance measure is a crucial method to identify and evaluate the system weak link. It is widely used in the optimization design and maintenance decision of aviation, aerospace, nuclear energy and other systems. The dissimilar redundancy actuation system (DRAS) is a key aircraft control subsystem which performs aircraft attitude and flight trajectory control. Its performance and reliability directly affect the aircraft flight quality and flight safety. This paper considers the influence of the Birnbaum importance measure (BIM) and integrated importance measure (IIM) on the reliability changes of key components in DRAS. The differences of physical fault characteristics of different …


A Pilot Course As A Step Towards New Academic Programs In Renewable Energies, Otilia Popescu, Orlando Ayala, Isaac Flory, Jose Fernandez, Vukica Jovanović Jan 2022

A Pilot Course As A Step Towards New Academic Programs In Renewable Energies, Otilia Popescu, Orlando Ayala, Isaac Flory, Jose Fernandez, Vukica Jovanović

Engineering Technology Faculty Publications

The challenges arising from climate change have never before in human history been more pressing for solutions. Addressing pollution and the transition to clean energies are essential problems to solve in the upcoming decades. The process of transitioning to renewable energies has started already, with some states leading the process. As the development of industries sees a fast growth, the supply of qualified engineers and technicians to support these industries needs to keep up. At the community college level, some efforts have already started to introduce courses on renewable energies as well as boot camps or certifications to prepare the …


Reconfigurable Modules For Automatic Creating Robotic Courses, Ana Djuric, Vukica Jovanovic Jan 2022

Reconfigurable Modules For Automatic Creating Robotic Courses, Ana Djuric, Vukica Jovanovic

Engineering Technology Faculty Publications

The main objective of this paper is to describe a teaching tool that can be used for automated creation of different problems that can be used for assessing student knowledge while teaching industrial robotics courses. These materials can be used for instructors who need to create customized questions and answers for different student homework. Wayne State University, Detroit, MI offer different industrial robotics and courses related to fundamental robotic theory: kinematics, dynamics, and control. Old Dominion University, Norfolk, VA offers the course in Introduction to Industrial Robotics. Both programs are Mechanical Engineering Technology under the Engineering Technology departments / division. …


Alkaline Plasma-Activated Water (Paw) As An Innovative Therapeutic Avenue For Cancer Treatment, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Miao Qi, Dehui Xu, Renwu Zhou, Dingxin Liu, Michael G. Kong Jan 2022

Alkaline Plasma-Activated Water (Paw) As An Innovative Therapeutic Avenue For Cancer Treatment, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Miao Qi, Dehui Xu, Renwu Zhou, Dingxin Liu, Michael G. Kong

Bioelectrics Publications

Plasma-activated water (PAW) is considered to be an effective anticancer agent due to the diverse aqueous reactive oxygen and nitrogen species (RONS: ROS and RNS), but the drawback of low dose and short duration of RONS in acidified PAW limits their clinical application. Herein, this Letter presents an innovative therapeutic avenue for cancer treatment with highly-effective alkaline PAW prepared by air surface plasma. This anticancer alkaline formulation is comprised of a rich mixture of highly chemical RONS and exhibited a prolonged half-life compared to acidified PAW. The H2O2, NO2-, and ONOO-/O2 …


Definition And Detection Of Hypervulnerabilities Using A Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo Jan 2022

Definition And Detection Of Hypervulnerabilities Using A Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo

VMASC Publications

Long term plans for maritime ports are identifying investments that will increase their capacity while decreasing their environmental footprint and operating costs. These changes are leading to increases in complexity at a time when leaner practices are driving investments to become more strategic. As such, this work proposes a generalized definition that allows a system or entity to be classified as exceedingly vulnerable by comparing it to other entities. This definition is developed from a set of definitions gathered from disparate fields. From this definition grounded in theory, the initial rules for complex system implementation are developed and demonstrated on …


Tension-Stiffening Effect Consideration For Modeling Deflection Of Cracked Reinforced Uhpc Beams, Le Teng, Rongling Zhang, Kamal Khayat Jan 2022

Tension-Stiffening Effect Consideration For Modeling Deflection Of Cracked Reinforced Uhpc Beams, Le Teng, Rongling Zhang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tension-stiffening effects can significantly influence the flexural performance of cracked reinforced concrete specimens. Such effect is amplified for fiber-reinforced concrete, given the fact that fibers can bridge the cracks. The objective of this study was to develop a model to predict the deflection of cracked reinforced ultra-high performance concrete (R-UHPC) beam elements. The modeling approach characterized the average bending moment of inertia by combining the existing model used for conventional reinforced concrete and the analytical model of stress distribution of UHPC along the cross-section. The finite element analysis (FEA) was employed to evaluate the flexural deflection based on the average …


Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill Jan 2022

Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the recent widespread adoption of LED lighting in outdoor areas, numerous concerns have been raised about the potential for harmful effects on humans, animals, plants, and the night sky. These stem from the high blue light content of some LED bulbs and an incentive to increase lighting levels caused by higher efficiency and lower costs. While new lighting installations are often described as environmentally friendly due to their energy efficiency, factors such as light pollution are often neglected or not given enough weight. This research focuses on optimizing the design of exterior lighting for human, environmental, and economic factors …


Magnetic Field Penetration Technique To Study Field Shielding Of Multilayered Superconductors, Iresha Harshani Senevirathne, Alex Gurevich, Jean R. Delayen, A-M Valente-Feliciano Jan 2022

Magnetic Field Penetration Technique To Study Field Shielding Of Multilayered Superconductors, Iresha Harshani Senevirathne, Alex Gurevich, Jean R. Delayen, A-M Valente-Feliciano

Physics Faculty Publications

The SIS structure which consists of alternative thin layers of superconductors and insulators on a bulk niobium has been proposed to shield niobium cavity surface from high magnetic field and hence increase the accelerating gradient. The study of the behavior of multilayer superconductors in an external magnetic field is essential to optimize their SRF performance. In this work we report the development of a simple and efficient technique to measure penetration of magnetic field into bulk, thin film and multilayer superconductors. Experimental setup contains a small superconducting solenoid which can produce a parallel surface magnetic field up to 0.5 T …


Maintenance Optimization In A Digital Twin For Industry 4.0, Abhijit Gosavi, Vy Khoi Le Jan 2022

Maintenance Optimization In A Digital Twin For Industry 4.0, Abhijit Gosavi, Vy Khoi Le

Engineering Management and Systems Engineering Faculty Research & Creative Works

The advent of Internet of Things and artificial intelligence in the era of Industry 4.0 has transformed decision-making within production systems. In particular, many decisions that previously required significant human activity are now made automatically with minimal human intervention via so-called digital twins (DTs). In the context of maintenance and reliability modeling, this naturally calls for new paradigms that can be seamlessly integrated within DTs for decision-making. The input data for time to failure needed in reliability computations are directly collected from the work center in a digital setting and often do not satisfy a known distribution. A neural network …


Extraction Of Stripline Surface Roughness Using Cross-Section Information And S-Parameter Measurements, Zeyi Sun, Jian Liu, Xiaoyan Xiong, Victor Khilkevich, Donghyun Kim, Darvl Beetner Jan 2022

Extraction Of Stripline Surface Roughness Using Cross-Section Information And S-Parameter Measurements, Zeyi Sun, Jian Liu, Xiaoyan Xiong, Victor Khilkevich, Donghyun Kim, Darvl Beetner

Engineering Management and Systems Engineering Faculty Research & Creative Works

To characterize additional conductor loss introduced by conductor surface roughness, various models have been proposed to describe the relationship between foil roughness levels and surface roughness correction factor. However, all these empirical or physical models require a PCB sample to be manufactured and analyzed in advance. The procedure requires dissecting the PCB and is time- and labor-consuming. To avoid such a process, a new surface roughness extraction process is proposed here. Only the measured S-parameter and nominal cross-sectional information of the board are needed to extract the roughness level of conductor foils. Besides, this method can also deal with boards …


Monte Carlo Particle Simulation Of Avalanche Breakdown In A Reverse Biased Diode With Full Band Structure, Zeyi Sun, Manish Kizhakkeveettil Mathew, Ryan From, Donghyun Kim Jan 2022

Monte Carlo Particle Simulation Of Avalanche Breakdown In A Reverse Biased Diode With Full Band Structure, Zeyi Sun, Manish Kizhakkeveettil Mathew, Ryan From, Donghyun Kim

Engineering Management and Systems Engineering Faculty Research & Creative Works

To model the avalanche breakdown of a voltage regulator diode under reverse bias, a computationally rigorous device physics model using the Monte Carlo method to solve charge carrier Boltzmann transport equations (BTEs) is proposed. The transport of energetic charge carriers is calculated by using the full energy band instead of the non-parabolic band structure. The position-dependent doping profile found in real diodes is modeled accurately and time-efficiently. A two-step method is introduced to accelerate the simulation of avalanche breakdown. With the proposed model, the expected IV characteristics of a voltage regulator diode under reverse bias are simulated. The transport of …