Engineering Commons^™

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

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

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

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

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

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

Honors Program: Senior Projects (Public)

The following project report was a study of the North 14^th 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 14^th Street and the 14^th 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

TLC Newsletter

No abstract provided.

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

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

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

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 …

A Magnetic Nanoparticle-Doped Photopolymer For Holographic Recording, Muhammad Irfan, Suzanne Martin, Muhammad Ahmed Obeidi, Scott Miller, Frank Kuster, Dermot Brabazon, Izabela Naydenova

Articles

Functionalised holograms are important for applications utilising smart diffractive optical elements for light redirection, shaping and in the development of sensors/indicators. This paper reports on holographic recording in novel magnetic nanocomposites and the observed temperature change in dry layers and liquid samples exposed to alternating magnetic field (AMF). The nanocomposite consists of N-isopropylacrylamide (NIPA)-based polymer doped with magnetic nanoparticles (MNPs), and local heating is achieved through magnetic induction. Here, volume transmission holographic gratings (VTHGs) are recorded with up to 24% diffraction efficiency (DE) in the dry layers of magnetic nanocomposites. The dry layers and liquid samples are then exposed to …

Ammonia Cycling And Emerging Particulate Matter Pollutants Under Arable Land-Use Management: A Modelling Approach, Vivien Pohl

Doctoral

Air quality monitoring in Ireland is under the jurisdiction of the Environmental Protection Agency in compliance with the Gothenburg Protocol, EU/national legislation, and the National Clean Air Strategy. Particulate Matter (PM) has been acknowledged as a key atmospheric pollutant, with serious public health impacts and no safe threshold of exposure in place to-date. Ammonia (NH3) emissions are linked to the secondary production of PM through atmospheric reactions occurring with acidic atmospheric components such as sulfuric acid, nitric acid, and hydrochloric acid. These reactions result in the formation of ammonium sulfate, ammonium nitrate and ammonium chloride, among others. More than 95% …

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

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

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

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

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^-/O_{2 …}

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 …

Electromagnetic-Thermal Co-Simulation Of Microstrip Filter, Xin Yi Liu, Zheng Lang Jia, Huan Huan Zhang, Ying Liu, W. E.I. Sha, L. (Lijun) J. Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

An electromagnetic-thermal co-simulation method is proposed for microstrip filter in this paper. The Maxwell equation is solved by discontinuous Galerkin time-domain (DGTD) method, while thermal simulation is carried out based on finite-element time-domain (FETD) method. Electromagnetic and thermal simulations are coupled by power loss and temperature-dependent conductivity. At last, the method is applied to analyze the microstrip low-pass filter.

Dual-Band Decoupling Network For Mimo Antennas, Min Li, Lijun Jiang, Kwan Lawrence Yeung

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel method to design a decoupling network (DN) to increase isolation between dual-band antennas. The DN design is based on the scattering matrix and optimized by the Genetic Algorithm (GA). The decoupling example shows that the DN offers impedance matching and high isolation within desired bands, verifying the concept.

Analysis Of The Shielding Effectiveness Of Chassis Based On Dgtd Method, Zheng Lang Jia, Lei Zhao, Zhao Sheng Xue, Ying Liu, Huan Huan Zhang, L. (Lijun) J. Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

An electromagnetic simulation method is proposed for shielding effectiveness (SE) of chassis in this paper. The discontinuous Galerkin time-domain (DGTD) equation is established based on Maxwell's equation. The uniaxial perfectly matched layer (UPML) is used as an absorbing boundary condition to simulate an open space. At last, the method is applied to analyze the effect of the aspect ratios of rectangular apertures on shielding effectiveness.

Guest Editorial, Ming Yu, Lijun Jiang, Alex M.H. Wong

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A Fast Awe-Augmented Wideband Discontinuous Galerkin Frequency-Domain Method In Solving Electromagnetic Wave Equations, Shi Min Liu, Li (Lijun) Jun Jiang, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

In this research, a discontinuous Galerkin frequency-domain (DGFD) method is proposed to solve the electromagnetic wave equations. Different to the explicit time-domain analysis, the electric-field and magnetic-field in frequency-domain wave equations are coupled together implicitly, thus the established matrix equation is globally coupled, which is computational expensive if solving it directly. To address this issue, a Block-diagonal preconditioner and a restriction operator are applied to the matrix equation, which splits the global matrix into a number of small local matrix systems pertinent to each subdomain. Then, a direct solver can be employed to solve them with a FETI-like procedure. Besides, …

Graphene-Based Terahertz Holographic Conformal Antenna, Peng Fei Ren, Li (Lijun) Jun Jiang, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a conformal graphene holographic antenna designed for terahertz (THz) band is proposed. The radiation principle of the proposed pattern reconfigurable antenna is based on the holographic technology. The surface reactance modulation and pattern steering capability can be easily facilitated by a tunable DC-biased graphene patch array. Thanks to the super thin structure and excellent mechanical property of graphene, the proposed THz graphene holographic antenna can be designed conformal to required platforms easily. Besides, the equal size as well as same spacing of graphene patches make it easy to modeling and manufacture. To verify the proposed idea, an …

Modeling Of Spatial-Temporal Sea Clutter With I/Q Components Based On The Data-Driven Approximation Of Koopman Theory, Y. M. Zhang, L. (Lijun) J. Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel data-driven approximation of the Koopman theory algorithm is proposed to simulate the coherent and spatial-temporal correlated sea clutter. The evolution of sea clutter's in-phase and quadrature (I/Q) components are well simulated on the state space. Meanwhile, the amplitude distribution and the phase retrieval of sea clutter can be extracted and modeled. The experimental sea clutter data measured by the IPIX radar is used to demonstrate that this newly proposed data-driven approximation of the Koopman theory algorithm can simulate the sea clutter with the phase retrieval, the expected amplitude information, and the spatial-temporal relationship. Our work …

Modeling Radiated Emissions From Pcbs In Shielding Enclosures Based On A Numerical Green's Function Approach, Zi An Wang, Li (Lijun) Jun Jiang, Jun Fa Mao, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

To accurately and efficiently model the radiated emissions from printed circuit boards (PCBs) placed in shielding enclosures, in this work, a novel approach based on the numerical Green's function (NGF) is proposed. In terms of Schelkunoff's equivalence principle, if the interior of the shielding enclosure is filled up with perfectly electric conductor (PEC), only tangential electric fields over the ventilation slots are sufficient to obtain the radiated emissions. However, due to the presence of the PEC filled shielding box, the in-situ Green's function is not available. To conquer this problem, the proposed approach can be split into two steps. In …

Proportional Fair Clustered Federated Learning, Mohamed Nafea, Eugine Shin, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

This paper studies federated learning (FL) with non-identical data generating distributions and under the notion of proportional fairness. Users are partitioned into disjoint clusters based on their data distributions, and a distinct model is learnt for each cluster. Different than previous work that considered clustering to optimize personalized learning performance, here clustering is inspected under the disparate impact doctrine which requires that protected classes (e.g., those of certain race or gender) have representations in every cluster that are approximately equal to their representation in the overall set of users. A family of iterative algorithms that balance the learning performance and …

Temperature-Insensitive Inclinometer Based On Transmission Line Fabry-Perot Resonators, Jing Guo, Chen Zhu, Yan Tang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This Article Reports a Novel Self-Compensated Inclinometer with a Wide Dynamic Range and High Measurement Resolution based on Two Hollow Coaxial Cable Fabry-Perot Resonators (HCC-FPRs). the HCC-FPR is Formed between a Metal Post that Shorts the Inner Conductor and the Outer Conductor of the HCC and the Water Level Inside the HCC. Changes in Tilt Angles Result in Variations of the Water Level in the HCC, Leading to Changes in the Cavity Length of the HCC-FPR. by Tracking the Shift of the Resonance Wavelength of the HCC-FPR, a Single HCC-FPR Can Be Used as a Sensor Device for Tilt Measurements. …