Engineering Commons^™

A Novel Subdomain 2d/Q-2d Finite Element Method For Power/Ground Plate-Pair Analysis, Ping Li, Li (Lijun) Jun Jiang, Min Tang, Yao Jiang Zhang, Shuai Xu, Hakan Bagc

Electrical and Computer Engineering Faculty Research & Creative Works

Upon excitation by a surface magnetic current, a power/ground plate-pair supports only TMz modes. This means that the magnetic field has only azimuthal components permitting a simple but effective domain decomposition method (DDM) to be used. In the proximity of an antipad, field interactions are rigorously modeled by a quasi-two-dimensional (Q-2D) finite element method (FEM) making use of three-dimensional (3D) triangular prism mesh elements. Since high-order TMz modes are confined in the close proximity of the antipad, field interactions in the region away from the antipad only involve the fundamental mode and are rigorously modeled by a 2D FEM. This …

Ebg Common-Mode 20-Ghz Microstrip And Stripline Filters: Sensitivity To Design Parameters, Marina Y. Koledintseva, Sergiu Radu, Joseph Nuebel

Electrical and Computer Engineering Faculty Research & Creative Works

In this article, design and characteristics of 20-GHz electromagnetic bandgap (EBG) common-mode (CM) filters for microstrip (MS) and strip line (SL) differential pairs are considered. CM filter notch (resonance) frequency, depth, and width at the-15 dB level are calculated from the mixed-mode S-parameters. The agreement between the measured and modeled S-parameters of the baseline structures validates the models and allows for further numerical experiments. The systematic analysis of the trends for both MS and SL filter characteristics as functions of various geometrical and material design parameters is presented. Sensitivity to various technological features (conductor surface roughness, trapezoid shape of the …

Systematic Power Integrity Analysis Based On Inductance Decomposition In A Multi-Layered Pcb Pdn, Biyao Zhao, Siqi Bai, Samuel Connor, Stephen Scearce, Matteo Cocchini, Brice Achkir, Albert E. Ruehli, Bruce Archambeault, Jun Fan, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

An approach is presented for power integrity analysis on multi-layer printed circuit boards in this paper. Two critical current paths are analyzed. Inductance decomposition is applied to identify the critical parameters that can influence the PDN input impedance. Two types of stack-ups are used to perform sensitivity analysis to illustrate the effectiveness of PDN design guidelines. Based on the analysis of the inductance contribution from different blocks in the PCB PDN, a systematic approach to obtain a complete understanding of PDN behavior is proposed. The approach can be used to provide design guidance in PDN design practice.

Determine Socket's Inductance And Contact Resistance By Using Prf Method, Tao Wang, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, an accurate socket modeling methodology is proposed for signal integrity and power integrity applications using a quasi-static EM solver and considering the contact resistance of the socket which is a non-negligible component in socket modeling. The contact resistance characterization of a specific pogo-pin socket has been conducted by measuring the socket mounted on a specially designed test vehicle. A Parallel Resonance Frequency (PRF) method [1] is used to validate the EM model and to extract the contact resistance accurately.

Immunity Enhancement Of The Power Distribution Network In Integrated Circuits With Coplanar Meander Lines In Package, Bo Pu, Jun Fan, Wansoo Nah

Electrical and Computer Engineering Faculty Research & Creative Works

Integrated circuits suffer from interference in frequency multibands in real scenarios, and this susceptibility allows them to easily malfunction. In this article, a novel miniature coplanar filter in package to enhance the immunity of integrated circuits is proposed. The coplanar structure of the filter can avoid cost issues of the multilayers and can also be implemented in the substrate or interposer of the package, and also in a flexible/foldable board, with normal board, fabrication process. Analysis of the filtering characteristics and design method of a miniature filter with the required stop bands are demonstrated in detail. The designed band-stop filter …

Preparation And Analysis Of Cement Bricks Based On Rice Straw, Hend Ahmed, Ibrahim M. Ibrahim, M. A. Radwan, M. A. Sadek, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

In Egypt, rice straw is burnt as an easy and the cheap method to get rid of it leads to making a giant black cloud covers Cairo and southern delta governorates. Main purpose of this research is to produce green brick of cement and in-expensive agriculture waste (rice straw) with law price and good characteristics of thermal insulation and acoustic resistance. Different samples of cement brick based on rice straw of many percentages were prepared. First, select best mixture of concrete brick before adding rice straw after preparing and leave for curing time. Then, rice straw is added with various …

A Simplified Method For Experimentally Quantifying Crude Oil Swelling During Immiscible Carbon Dioxide Injection, Sherif Fakher, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Immiscible carbon dioxide (CO₂) injection is one of the highly applied enhanced oil recovery (EOR) methods due to its high oil recovery potential and its ability to store CO₂ in the reservoir. The main mechanism of immiscible CO₂ injection is oil swelling. Generally, oil swelling is measured experimentally or measured using modeling methods. This research conducts oil swelling experiments using a simplified method in order to easily and accurately measure oil swelling and determines some of the most significant factors that may impact oil swelling during CO₂ injection. The impact of varying CO₂ injection …

Measuring Three-Dimensional Temperature Distributions In Steel-Concrete Composite Slabs Subjected To Fire Using Distributed Fiber Optic Sensors, Yi Bao, Matthew S. Hoehler, Christopher M. Smith, Matthew Bundy, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Detailed information about temperature distribution can be important to understand structural behavior in fire. This study develops a method to image three-dimensional temperature distributions in steel–concrete composite slabs using distributed fiber optic sensors. The feasibility of the method is explored using six 1.2 m × 0.9 m steel–concrete composite slabs instrumented with distributed sensors and thermocouples subjected to fire for over 3 h. Dense point clouds of temperature in the slabs were measured using the distributed sensors. The results show that the distributed sensors operated at material temperatures up to 960◦C with acceptable accuracy for many structural fire applications. The …

Microstructural Influence On Mechanical Properties Of A Lightweight Ultrahigh Strength Fe-18mn-10al-0.9c-5ni (Wt%) Steel, Michael Piston, Laura Bartlett, Krista R. Limmer, Daniel M. Field

Materials Science and Engineering Faculty Research & Creative Works

This study evaluates the role of thermomechanical processing and heat treatment on the microstructure and mechanical properties of a hot rolled, annealed, and aged Fe-18Mn-10Al-0.9C-5Ni (wt%) steel. The steel exhibited rapid age hardening kinetics when aged in the temperature range of 500-600 ⁰C for up to 50 h, which has been shown in other work to be the result of B2 ordering in the ferrite and K-carbide precipitation within the austenite matrix. The ultimate tensile strength increased from 1120 MPa in the annealed condition to 1230 MPa after 2 h of aging at 570 ⁰C. Charpy V-notch toughness was evaluated …

Benefits Of Including Sae Bolts, Nuts, And Washers In The Aisi Standard S100, Patrick Bodwell, Perry S. Green

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The addition of SAE J429 bolts along with their associated nuts and washers into the AISI STANDARD S100, North American Specification for the Design of Cold-Formed Members, would be a significant enhancement to the specification by providing practitioners the opportunity to use a broader range of fasteners for the design of cold-formed steel structures. The design of bolted connections using SAE J429 bolts would be advantageous for many types of structures including mechanical support structures, storage rack systems, photovoltaic support structures, carport structures, and conventional repetitive frame structures that all utilize cold-formed steel members. These structures would benefit by having …

An Explainable And Statistically Validated Ensemble Clustering Model Applied To The Identification Of Traumatic Brain Injury Subgroups, Dacosta Yeboah, Louis Steinmeister, Daniel B. Hier, Bassam Hadi, Donald C. Wunsch, Gayla R. Olbricht, Tayo Obafemi-Ajayi

Electrical and Computer Engineering Faculty Research & Creative Works

We present a framework for an explainable and statistically validated ensemble clustering model applied to Traumatic Brain Injury (TBI). The objective of our analysis is to identify patient injury severity subgroups and key phenotypes that delineate these subgroups using varied clinical and computed tomography data. Explainable and statistically-validated models are essential because a data-driven identification of subgroups is an inherently multidisciplinary undertaking. In our case, this procedure yielded six distinct patient subgroups with respect to mechanism of injury, severity of presentation, anatomy, psychometric, and functional outcome. This framework for ensemble cluster analysis fully integrates statistical methods at several stages of …

Factors Affecting Brittleness Behavior Of Coal-Gangue Ceramsite Lightweight Aggregate Concrete, Yunsen Wang, Jingping Qiu, Wen Deng, Jun Xing, Jian Liang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Coal gangue, which is the solid waste produced during the coal processing, causes serious environmental problems. Lightweight concrete by making use of the coal-gangue ceramsite as the aggregate has many advantages as the construction material. However, the high brittleness of lightweight aggregate concrete is one of the problems for its application in building infrastructure. In this paper, the variation regularity, influencing factors and reinforcing/toughening method were studied as the reference data for future practical applications of coal-gangue ceramsite lightweight aggregate concrete (CGCLWAC). The results show that the brittleness of CGCLWAC increases with age, but the rate of the increase of …

An Algorithm For Adaptive Determination Of Radar Coherent Integration Time, Jakob Delong, Joel T. Johnson

Electrical and Computer Engineering Faculty Research & Creative Works

A method for adaptively determining a desirable coherent integration time for radar observations of a moving clutter target is examined. A signal model appropriate for such measurements is first defined, along with an approach for estimating the coherence time from measured data. This coherence time estimate is then used as the coherent integration time in a reprocessing of the measured data. Simulations are shown that illustrate the potential advantages of this approach in reducing the variance of the clutter power estimate, particularly at low clutter to noise ratios, as compared to a purely incoherent integration. However, the initial correlation time …

Hybrid Electro-Plasmonic Neural Stimulation With Visible-Light-Sensitive Gold Nanoparticles, Ratka Damnjanovic, Parveen Bazard, Robert D. Frisina, Venkat R. Bhethanabotla

Chemical and Biochemical Engineering Faculty Research & Creative Works

Biomedical prosthetics utilizing electrical stimulation have limited, effective spatial resolution due to spread of electrical currents to surrounding tissue, causing nonselective stimulation. So, precise spatial resolution is not possible for traditional neural prosthetic devices, such as cochlear implants. More recently, alternative methods utilize optical stimulation, mainly infrared, sometimes paired with nanotechnology for stimulating action potentials. Infrared stimulation has its own drawbacks, as it may cause collateral heating of surrounding tissue. In previous work, we employed a plasmonic method for stimulation of an electrically excitable neuroblastoma cell line, which had limited success. Here, we report the development of a hybrid electro-plasmonic …

Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen

INSPIRE Archived Webinars

This lecture will present an overview of the research, development, validation, and implementation of 'smart' rocks as in-situ agents to assist in remote monitoring of bridge scour in real time. It will start with a brief review of fundamental concepts such as magnet, polarization, magnetic field, and field measurement principle. It will then introduce the concept of ‘smart’ rocks, demonstrate it through small-scale laboratory tests, and design and fabricate gravity-controlled ‘smart’ rocks for field implementation based on river hydrodynamics and riverbed conditions. Next, a ‘smart’ rock localization optimization algorithm will be formulated analytically and validated experimentally in open fields. It …

Nanoparticle Catalyzed Hydrodesulfurization Of Diesel Fuel In A Trickle Bed Reactor: Experimental And Optimization Study, Saba A. Gheni, Saad A. Awad, Safaa M. R. Ahmed, Ghassan Abdullah, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work focuses on the preparation, simulation, and optimization of the hydrodesulfurization (HDS) of dibenzothiophene (DBT) using a nanocatalyst. A homemade nanocatalyst (3 percent Co, 10 percent Mo/γ-Al₂O₃ nanoparticles) was used in a trickle bed reactor (TBR). The HDS kinetic model was estimated based on experimental observations over ranges of operating conditions to evaluate kinetic parameters of the HDS process and apply the key parameters. Based on these parameters, the performance of the TBR catalyzed by the nanocatalyst was evaluated and scaled up to a commercial scale. Also, the selectivity of HDS reactions was also modeled to …

Mathematical Modeling And Pointwise Validation Of A Spouted Bed Using An Enhanced Bed Elasticity Approach, Sebastián Uribe, Binbin Qi, Omar Farid, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

With a Euler-Euler (E2P) approach, a mathematical model for predicting the pointwise hydrodynamic behavior of a spouted bed was implemented though computational fluid dynamics (CFD) techniques. The model considered a bed elasticity approach in order to reduce the number of required sub-models to provide closure for the solids stress strain-tensor. However, no modulus of elasticity sub-model for a bed elasticity approach has been developed for spouted beds, and thus, large deviations in the predictions are obtained with common sub-models reported in literature. To overcome such a limitation, a new modulus of elasticity based on a sensitivity analysis was developed and …

Heterogenous Trip Distance-Based Route Choice Behavior Analysis Using Real-World Large-Scale Taxi Trajectory Data, Yajuan Deng, Meiye Li, Qing Tang, Renjie He, Xianbiao Hu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Most early research on route choice behavior analysis relied on the data collected from the stated preference survey or through small-scale experiments. This manuscript focused on the understanding of commuters' route choice behavior based on the massive amount of trajectory data collected from occupied taxicabs. The underlying assumption was that travel behavior of occupied taxi drivers can be considered as no different than the well-experienced commuters. To this end, the DBSCAN algorithm and Akaike information criterion (AIC) were first used to classify trips into different categories based on the trip length. Next, a total of 9 explanatory variables were defined …

Component Analysis Of Bio-Asphalt Binder Using Crumb Rubber Modifier And Guayule Resin As An Innovative Asphalt Replacer, Ahmed Hemida, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This research seeks to interpret the component analysis of an innovative bio-asphalt binder using guayule resin in addition to crumb rubber modifier (CRM) at high concentrations. Such asphalt modification aims to minimize the dependency on virgin asphalt binder and provide new solutions concerning sustainable, flexible pavement industry. Guayule resin is a promising bioresource for asphalt binder replacement. By now, it could be considered a no value byproduct extracted during the guayule natural rubber production. CRM is a recycled material derived from scrap tires. The provided interpretation could help in understanding the asphalt-rubber-guayule interaction mechanism. Fourier transform infrared spectroscopy (FTIR), supported …

Peritectic Behavior Detection In The Fe-C-Mn-Al-Si Steel System Using Fiber Optic Temperature Mapping, Muhammad Roman, Damilola Balogun, Rex E. Gerald Ii, Laura Bartlett, Jie Huang, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Peritectic reactions can cause surface defects and breakouts in continuous casting and the peritectic region is often avoided by adjusting the chemical composition of the steel to cast outside of the peritectic sensitivity range. However, the combined effects of C, Mn, Al, and Si on the boundaries that map peritectic region are still disputed for many advanced high strength steel grades. An apparatus for performing controlled solidification experiments is being developed to characterize the effects of chemical composition on the uniformity of shell growth during solidification using a copper chill mold with an embedded fiber-optic temperature sensor that enables high …

A Modified Johnson-Cook Model Incorporating The Effect Of Grain Size On Flow Stress, S. Ganguly, Mario F. Buchely, K. Chandrashekhara, Semen Naumovich Lekakh, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

The mechanical properties of steel are influenced by grain size, which can change through mechanisms such as nucleation and growth at elevated temperatures. However, the classic Johnson-Cook model that is widely used in hot deformation simulations does not consider the effect of grain size on flow stress. In this study, the Johnson-Cook model was modified to incorporate the effects of austenite grain size on flow stress. A finite element model was employed to characterize the effects of grain size on the flow stress for different steel grades over a range of temperatures (900⁰ to 1300⁰). Simulation results show good agreement …

Interactions Between Dry Vibratable Tundish Linings And Steel Melts, Tyler M. Richards, Ronald J. O'Malley, Jeffrey D. Smith, Todd P. Sander

Materials Science and Engineering Faculty Research & Creative Works

Interactions between two tundish working linings and molten steel were investigated using industrial samples and laboratory testing. Periclase-based dry vibe linings from two production facilities were sampled and examined after casting: one containing 30 wt.% olivine and one without olivine. Cathodoluminescence imaging, secondary electron microscopy, energydispersive spectroscopy and x-ray diffraction analysis were performed to characterize the interactions. An experiment was developed to replicate the conditions found in a production tundish on the laboratory scale. Results comparing interactions observed in laboratory lining tests and commercial lining samples for the two lining materials are presented and discussed.

Scale Formation On 430 Stainless Steel In A Simulated Slab Combustion Reheat Furnace Atmosphere, Richard Osei, Semen Naumovich Lekakh, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Scale formed during slab reheating can be difficult to remove by high-pressure descaling, having a negative impact hot roll surface quality. A large-capacity thermogravimetric apparatus that replicates the combustion atmosphere and temperature in a slab reheat furnace was used to investigate scale formation on 430 stainless steel. Effects of reheating parameters (temperature, time and atmosphere) on oxidation kinetics were investigated. Oxidized samples were characterized by scanning electron microscopy, Raman spectroscopy and x-ray diffraction to document the microstructure and morphology of scale. Mechanisms for the formation of multi-layered oxide structures that complicate oxidation kinetics and scale removal are discussed.

New Experimental Apparatus To Investigate Hot Tearing Behavior In Steel, Yanru Lu, Laura Bartlett, Ronald J. O'Malley, Semen Naumovich Lekakh, Mario F. Buchely

Materials Science and Engineering Faculty Research & Creative Works

Hot tearing is a complex thermomechanical phenomenon occurring in the semi-solid region. Strain in this region can induce cracking and localized alloying element segregation. An apparatus for investigating hot tearing was developed utilizing a servo-motor controlled cylinder to apply a pre-determined amount of strain to the solidifying shell. A special mold was developed using filling and solidification modeling to ensure that dendrite growth was perpendicular to applied strain. A computer-automated system was utilized to control the strain and strain rate and measure the force and displacement. Solidification experiments utilizing AISI 1020 steel validated the apparatus capabilities and optimized testing parameters.

The Influence Of Ti, Nb And V On The Hot Ductility Of As-Cast Microalloyed Steels, Madhuri Varadarajan, Laura Bartlett, Ronald J. O'Malley, Semen Naumovich Lekakh

Materials Science and Engineering Faculty Research & Creative Works

Microalloying with Ti, Nb and V, both individually and in combination, is a common method for producing steels with high strength and toughness. However, interaction with other elements and impurities can lead to cracking during continuous casting and rolling. The hot ductility of commercially cast V, Nb and Nb-V-Ti steels has been investigated using two experimental methods: tensile testing utilizing a servo-hydraulic load frame with a resistance furnace and thermomechanical testing using rapid joule heating. The temperature-dependent ductility of these steels is compared for both test methods. Factors that influence the ductility of these steels are discussed.

Structural Design Example -- Four Span Metal Building Z-Purlin Line Supporting A Standing Seam Roof, Christopher D. Moen

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This example provides a step-by-step strength calculation of a 4-span continuous Z-purlin system supporting a standing seam roof.

Design inputs are defined first, including cross-section dimensions and orientation, span lengths, roof slope, and bracing provided by the standing seam to the purlin line. The calculations consider gravity (downward) and suction (uplift) loadings.

Bridge Infrastructure Asset Management System: Comparative Computational Machine Learning Approach For Evaluating And Predicting Deck Deterioration Conditions, Rayan Assaad, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Bridge infrastructure asset management system is a prevailing approach toward having an effective and efficient procedure for monitoring bridges through their different development phases including construction, operation, and maintenance. Damage to any structural component of a bridge will negatively affect its safety, integrity, and longevity. Bridge decks are more susceptible to severe deterioration because they are exposed to harsh conditions including heavy traffic, varying temperatures, road salts, and abrasive forces. The ability to forecast the conditions of bridges in an accurate way has been a great challenge to transportation agencies. Many previous research studies highlighted the need to have a …

A Machine-Learning-Enhanced Hierarchical Multiscale Method For Bridging From Molecular Dynamics To Continua, Shaoping Xiao, Renjie Hu, Zhen Li, Siamak Attarian, Kaj Mikael Björk, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

In the Community of Computational Materials Science, One of the Challenges in Hierarchical Multiscale Modeling is Information-Passing from One Scale to Another, especially from the Molecular Model to the Continuum Model. a Machine-Learning-Enhanced Approach, Proposed in This Paper, Provides an Alternative Solution. in the Developed Hierarchical Multiscale Method, Molecular Dynamics Simulations in the Molecular Model Are Conducted First to Generate a Dataset, Which Represents Physical Phenomena at the Nanoscale. the Dataset is Then Used to Train a Material Failure/defect Classification Model and Stress Regression Models. Finally, the Well-Trained Models Are Implemented in the Continuum Model to Study the Mechanical Behaviors …

Application Of Quantum-Markov Open System Models To Human Cognition And Decision, Jerome Busemeyer, Qizi Zhang, S. N. Balakrishnan, Zheng Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Markov processes, such as random walk models, have been successfully used by cognitive and neural scientists to model human choice behavior and decision time for over 50 years. Recently, quantum walk models have been introduced as an alternative way to model the dynamics of human choice and confidence across time. Empirical evidence points to the need for both types of processes, and open system models provide a way to incorporate them both into a single process. However, some of the constraints required by open system models present challenges for achieving this goal. The purpose of this article is to address …

How Does Three-Dimensional Canopy Geometry Affect The Front Propagation Of A Gravity Current?, Jian Zhou, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Large-eddy simulations are performed to investigate how three-dimensional canopy geometry affects the front propagation of an incoming gravity current under a given initial forcing. A regular array of rigid square cylinders are used to represent the distributed canopy elements. It is shown that the conventional geometrical parameter of submerged canopies in constant-density flows (ah, where a is the frontal area per canopy volume and h is the canopy height) is misleading when applied to buoyancy-driven flows due to the additional complexity arising from the internal density gradients. Instead, the present study suggests a new geometrical framework consisting of a canopy …