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2022

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Articles 5821 - 5850 of 9379

Full-Text Articles in Engineering

Characterizing Hydrostratigraphic Communication Of The Semi-Consolidated Sediment Aquifers Of The Flathead Valley In Northwestern Montana Through Hydrogeophysical Surveys, Elizabeth Katherine Breitmeyer Apr 2022

Characterizing Hydrostratigraphic Communication Of The Semi-Consolidated Sediment Aquifers Of The Flathead Valley In Northwestern Montana Through Hydrogeophysical Surveys, Elizabeth Katherine Breitmeyer

Graduate Theses & Non-Theses

To accurately forecast the cascading effects of increased stress to a hydrologic system, characterization of the continuity and permeability of the primary confining layer (PCL) separating the shallow and deep intermontane alluvial aquifers is required. Geophysical methods provide a faster cost-effective alternative to drilling to acquire additional information on the changes of hydrostratigraphy with depth. Geoelectric resistivity models recovered through inversion of TEM central loop sounding data to delineate changes in geoelectric properties with depth, providing information on the depth, thickness and resistivity of the hydrostratigraphy. Comparison of geoelectric resistivity models with well completion report lithologies yield information about the …


Treatment Of Mine Tailings Through Two Methods Of Calcite Precipitation: (I) Using Natural Mineral Trona, (Ii) Microbially Induced Calcite Precipitation Via Denitrification, Nathaniel Small Apr 2022

Treatment Of Mine Tailings Through Two Methods Of Calcite Precipitation: (I) Using Natural Mineral Trona, (Ii) Microbially Induced Calcite Precipitation Via Denitrification, Nathaniel Small

Graduate Theses & Non-Theses

Mine tailings not only pose environmental risks such as dust emission and acid mine drainage but also present geotechnical risks in cases of tailings dam failures which could lead to loss of human life and severe damages to infrastructure. In-situ cementation of tailings has the potential to reduce the risks associated with such failures as well as the related environmental problems. Over the years, different methods of chemically and microbially induced cementation of tailings have been examined many of which have shown promising results on a laboratory scale and some even on a ϐield scale. In this paper, a new …


A Parallelizable Algorithm For Stabilizing Large Sparse Linear Systems With Uncertain Interconnections, Aleksandar Zečević, Maryam Khanbaghi Apr 2022

A Parallelizable Algorithm For Stabilizing Large Sparse Linear Systems With Uncertain Interconnections, Aleksandar Zečević, Maryam Khanbaghi

Electrical and Computer Engineering

This paper proposes a new method for permuting sparse matrices into an upper block triangular from. The algorithm is highly parallelizable, which makes it suitable for large-scale systems with uncertain interconnection patterns. In such cases, the proposed decomposition can be used to develop flexible decentralized control strategies that produce a different gain matrix whenever the configuration changes. Applications to interconnected microgrids and supply and demand networks are provided to illustrate the versatility of the proposed approach.


Modelling And Validation Of A Gas-Solid Fluidized Bed Using Advanced Measurement Techniques, Sebastián Uribe, Haidar Taofeeq, Muthanna H. Al-Dahhan Apr 2022

Modelling And Validation Of A Gas-Solid Fluidized Bed Using Advanced Measurement Techniques, Sebastián Uribe, Haidar Taofeeq, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

With a Euler-two-phase (E2P) approach, through computational fluid dynamics (CFD) techniques, a mathematical model for the prediction of the local hydrodynamic behavior of a gas-solid fluidized bed was implemented. Simulations are conducted for a fluidized bed of 0.14 m internal diameter packed with Gerdart B glass beads particles, with an average diameter of 365 μm, at dimensionless inlet velocities ranging from (Formula presented.). The implemented model considers the multiphase and multiscale interactions through the inclusion of three sub-models, which allows the model to have a broad range of applicability. Predictions were compared against experimental measurements reported on previous contributions for …


Integrated Direct Air Capture And Oxidative Dehydrogenation Of Propane With Co2 At Isothermal Conditions, Shane Lawson, Khaled Baamran, Kyle Newport, Turki Alghamadi, Gary Jacobs, Fateme Rezaei, Ali A. Rownaghi Apr 2022

Integrated Direct Air Capture And Oxidative Dehydrogenation Of Propane With Co2 At Isothermal Conditions, Shane Lawson, Khaled Baamran, Kyle Newport, Turki Alghamadi, Gary Jacobs, Fateme Rezaei, Ali A. Rownaghi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Developing routes of utilizing CO2 emissions is important for long-term environmental preservation, as storing such emissions underground will eventually become unsustainable. One way of utilizing CO2 emissions is as a light-oxidant feedstock for oxidative dehydrogenation of propane (ODHP) to propylene. However, the adsorption and reaction steps typically occur at widely different temperatures, meaning that the thermal gradients – and by extension process energy requirements – are often unreasonably high. In recent years, dual-functional materials (DFMs) – i.e., materials comprised of a high temperature adsorbent phase alongside a heterogeneous catalyst – have been employed for combined CO2 adsorption …


Information-Based Particle Flow With Convergence Control, Kari C. Ward, Kyle J. Demars Apr 2022

Information-Based Particle Flow With Convergence Control, Kari C. Ward, Kyle J. Demars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A new formulation of the Gaussian particle flow filter is presented using an information theoretic approach. The developed information-based form advances the Gaussian particle flow framework in two ways: it imparts physical meaning to the flow dynamics and provides the ability to easily include modifications for a non-Bayesian update. An orbit determination simulation with high initial uncertainty is used to demonstrate the consistent, robust performance of the information flow filter in situations where the extended Kalman filter fails.


The Oxidation Of The Hisimo Cast Irons Alloyed With Cr/Al At 800 °C, Wenhui Zhu, Bruce A. Pint, Yang Huo, Larry Godlewski, Bita Ghaffari, Simon Lekakh, Carlos Engler-Pinto, Mei Li Apr 2022

The Oxidation Of The Hisimo Cast Irons Alloyed With Cr/Al At 800 °C, Wenhui Zhu, Bruce A. Pint, Yang Huo, Larry Godlewski, Bita Ghaffari, Simon Lekakh, Carlos Engler-Pinto, Mei Li

Materials Science and Engineering Faculty Research & Creative Works

To improve the oxidation resistance of cast iron containing Si and Mo (HiSiMo), 1wt.% Cr and 3wt.% Al were added into the base alloy to improve high temperature oxidation resistance for exhaust manifold applications. Oxidation tests were performed in both dry and wet air (air + 10% H2O) at 800 °C for 1, 10, 24, and 50 h. The mass change and oxide thickness were measured to evaluate the oxidation resistance. Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) and transmission electron microscopy (TEM) were employed to characterize the oxidized samples. The results showed that the additions of Al …


Effect Of Micro-Structural Dispersity Of Simo Ductile Iron On High Temperature Performance During Static Oxidation, Simon N. Lekakh, Asebi Bofah, Larry A. Godlewski, Mei Li Apr 2022

Effect Of Micro-Structural Dispersity Of Simo Ductile Iron On High Temperature Performance During Static Oxidation, Simon N. Lekakh, Asebi Bofah, Larry A. Godlewski, Mei Li

Materials Science and Engineering Faculty Research & Creative Works

High silicon and molybdenum (SiMo) ductile iron is commonly used for car exhaust systems, and its micro-structural dispersity depends on intrinsic parameters, which include alloy composition and inoculation efficiency, as well as extrinsic factors, such as casting wall thickness and molding material, which define cooling rate during solidification. Micro-structural dispersity is referred to as the degree of heterogeneity of sizes of structural constituencies within the microstructure. A variation in the micro-structural dispersity could impact the high temperature performance of SiMo ductile iron during static oxidation and transient thermo-mechanical loading conditions. In this study, static high temperature tests were performed on …


Topology-Based Accurate Modeling Of Current-Mode Voltage Regulator Modules For Power Distribution Network Design, Jingdong Sun, Yimajian Yan, Hanfeng Wang, Emil Chen, Ken Wu, Jun Fan Apr 2022

Topology-Based Accurate Modeling Of Current-Mode Voltage Regulator Modules For Power Distribution Network Design, Jingdong Sun, Yimajian Yan, Hanfeng Wang, Emil Chen, Ken Wu, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Power distribution network (PDN) is essential in electronic systems to provide reliable power for load devices. Thus, modeling of PDNs in printed circuit boards and packages has been extensively studied in the past few decades. However, with the higher integration levels and operation bandwidths of modern voltage regulator module (VRM), there lacks an accurate model for transient load responses based on the widely used current-mode control topology. In this work, a topology-based behavior model, including both the power stage and control loops, is developed for the current-mode buck VRM. A novel method is also proposed to unify the modeling of …


Analyzing The Influence Of Imbalanced Two- Or Three-Wire Vhf Lisn On Radiated Emissions From Ac Cables, Hossein Rezaei, Morten Sorensen, Wei Huang, Daryl G. Beetner, David Pommerenke Apr 2022

Analyzing The Influence Of Imbalanced Two- Or Three-Wire Vhf Lisn On Radiated Emissions From Ac Cables, Hossein Rezaei, Morten Sorensen, Wei Huang, Daryl G. Beetner, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

This article investigates using imbalanced two- and three-wire terminations for ac main cables, as suggested by the standard group. These terminations provide the basis for a new line impedance stabilization network (LISN) whose objective is to improve test repeatability between labs while also providing better estimation of real-world emissions. Standard balanced LISNs do not reproduce the imbalanced terminations seen in practice. An imbalanced two- or three-wire very high-frequency LISN was built, which can handle up to 15 A on each line. The LISN operates from 30 to 200 MHz and provides greater than 50-dB isolation between the input and output. …


A Compact High-Isolation Wideband Three-Sector Linear Array, Sheng Wu, Lidong Chi, Fuhai Li, Francesco De Paulis, Yihong Qi Apr 2022

A Compact High-Isolation Wideband Three-Sector Linear Array, Sheng Wu, Lidong Chi, Fuhai Li, Francesco De Paulis, Yihong Qi

Electrical and Computer Engineering Faculty Research & Creative Works

A compact and highly isolated three-sector linear array is proposed targeting point-to-point or point-to-multipoint data communication in Central Business District (CBD) and residential subdivision applications. It features wide bandwidth, high isolation among the units, low wind load, and low manufacturing and installation costs within the 400-500 MHz band. The driving element of the array unit is a wideband high-efficiency electromagnetic structure (WHEMS) applied in combination with the metal rods as passive elements for isolation purposes. The parasitic rod, shared by the adjacent units, decouples the mutual coupling by reducing the distance, which realizes not only the high isolation capability but …


Towards Improved Inertial Navigation By Reducing Errors Using Deep Learning Methodology, Hua Chen, Tarek M. Taha, Vamsy P. Chodavarapu Apr 2022

Towards Improved Inertial Navigation By Reducing Errors Using Deep Learning Methodology, Hua Chen, Tarek M. Taha, Vamsy P. Chodavarapu

Electrical and Computer Engineering Faculty Publications

Autonomous vehicles make use of an Inertial Navigation System (INS) as part of vehicular sensor fusion in many situations including GPS-denied environments such as dense urban places, multi-level parking structures, and areas with thick tree-coverage. The INS unit incorporates an Inertial Measurement Unit (IMU) to process the linear acceleration and angular velocity data to obtain orientation, position, and velocity information using mechanization equations. In this work, we describe a novel deep-learning-based methodology, using Convolutional Neural Networks (CNN), to reduce errors from MEMS IMU sensors. We develop a CNN-based approach that can learn from the responses of a particular inertial sensor …


Forecast Of Community Total Electric Load And Hvac Component Disaggregation Through A New Lstm-Based Method, Huangjie Gong, Rosemary E. Alden, Aron Patrick, Dan Ionel Apr 2022

Forecast Of Community Total Electric Load And Hvac Component Disaggregation Through A New Lstm-Based Method, Huangjie Gong, Rosemary E. Alden, Aron Patrick, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

The forecast and estimation of total electric power demand of a residential community, its baseload, and its heating ventilation and air-conditioning (HVAC) power component, which represents a very large portion of a community electricity usage, are important enablers for optimal energy controls and utility planning. This paper proposes a method that employs machine learning in a multi-step integrated approach. An LSTM model for total electric power at the main circuit feeder is trained using historic multi-year hourly data, outdoor temperature, and solar irradiance. New key temperature indicators, TmHAVC, corresponding to the standby zero-power operation for HVAC systems for summer cooling …


A Coupled Smoothed Particle Hydrodynamics-Discrete Element Method Framework For The Dynamic Response Of Saturated Geotechnical Systems, Saman Farzi Sizkow Apr 2022

A Coupled Smoothed Particle Hydrodynamics-Discrete Element Method Framework For The Dynamic Response Of Saturated Geotechnical Systems, Saman Farzi Sizkow

Civil and Environmental Engineering Theses and Dissertations

Investigating the past failures of various geotechnical systems during major seismic events, reveals the importance of developing a robust framework that can reliably analyze complex geotechnical systems. Up to now, fully continuum techniques have been the most popular choice for this type of problems. These methods use sophisticated constitutive models which need careful fine-tuning to successfully mimic the macro-scale dynamic behavior of coupled systems. The discrete element method (DEM) is, by nature, the best option for discontinuous systems such as soil. Furthermore, it has effective means to handle soil-structure interaction. Therefore, many attempts have been made to couple DEM with …


Remote Sensing For Energy Resources: Introduction, K. S. Sajinkumar, Thomas Oommen Apr 2022

Remote Sensing For Energy Resources: Introduction, K. S. Sajinkumar, Thomas Oommen

Michigan Tech Publications, Part 1

No abstract provided.


Site-Specific Site Response Analysis And Cascadia Subduction Zone Ground Motions Evaluation For A Site Near Portland, Brian Ackerman Apr 2022

Site-Specific Site Response Analysis And Cascadia Subduction Zone Ground Motions Evaluation For A Site Near Portland, Brian Ackerman

Civil and Environmental Engineering Master's Project Reports

Site-specific ground motions, site-specific site response analysis, and development of site-specific acceleration ground spectra at the ground surface was developed per ASCE 7-10 for the Kirkland Renaissance Boardwalk, a site in Vancouver, Washington.

Synthetic broadband ground motions developed specifically for Cascadia Subduction Zone (CSZ) megathrust earthquake were used for site-response analysis. The results of site-specific site response analyses using the strong motions were compared with the results from the 5 motions considered for the ASCE 7-10 procedure. The effect of motion duration and other ground motion intensity measures on the results of the site-specific site response analysis was investigated.

Similar …


Thermal Simulation Of Additive Manufacturing From G-Code, Noah Foster Apr 2022

Thermal Simulation Of Additive Manufacturing From G-Code, Noah Foster

Honors Capstones

No abstract provided.


Analytical, Numerical, And Computational Simulation Of The Free Convection Cooling Of An Electronics Enclosure For Assistive Painting Device, Jack Clement Apr 2022

Analytical, Numerical, And Computational Simulation Of The Free Convection Cooling Of An Electronics Enclosure For Assistive Painting Device, Jack Clement

Honors Capstones

No abstract provided.


Directed 3d Chemotaxis Of Cancer Cells In Response To Oscillating Chemical Gradients Using A Microfluidic Device, Trevor R. Thrasher Apr 2022

Directed 3d Chemotaxis Of Cancer Cells In Response To Oscillating Chemical Gradients Using A Microfluidic Device, Trevor R. Thrasher

Honors Capstones

No abstract provided.


Low-Intensity Blast Induces Acute Glutamatergic Hyperexcitability In Mouse Hippocampus Leading To Long-Term Learning Deficits And Altered Expression Of Proteins Involved In Synaptic Plasticity And Serine Protease Inhibitors, Shanyan Chen, Heather R. Siedhoff, Hua Zhang, Pei Liu, Ashley Balderrama, Runting Li, Catherine E. Johnson, C. Michael Greenlief, Bastijn Koopmans, Timothy Hoffman, Ralph G. Depalma, De Pei Li, Jiankun Cui, Zezong Gu Apr 2022

Low-Intensity Blast Induces Acute Glutamatergic Hyperexcitability In Mouse Hippocampus Leading To Long-Term Learning Deficits And Altered Expression Of Proteins Involved In Synaptic Plasticity And Serine Protease Inhibitors, Shanyan Chen, Heather R. Siedhoff, Hua Zhang, Pei Liu, Ashley Balderrama, Runting Li, Catherine E. Johnson, C. Michael Greenlief, Bastijn Koopmans, Timothy Hoffman, Ralph G. Depalma, De Pei Li, Jiankun Cui, Zezong Gu

Mining Engineering Faculty Research & Creative Works

Neurocognitive consequences of blast-induced traumatic brain injury (bTBI) pose significant concerns for military service members and veterans with the majority of "invisible injury." However, the underlying mechanism of such mild bTBI by low-intensity blast (LIB) exposure for long-term cognitive and mental deficits remains elusive. Our previous studies have shown that mice exposed to LIB result in nanoscale ultrastructural abnormalities in the absence of gross or apparent cellular damage in the brain. Here we tested the hypothesis that glutamatergic hyperexcitability may contribute to long-term learning deficits. Using brain slice electrophysiological recordings, we found an increase in averaged frequencies with a burst …


Measuring Volatile Emissions From Moss Gametophytes: A Review Of Methodologies And New Applications, Danlyn L. Brennan, Leslie M. Kollar, Scott Kiel, Timea Deakova, Aurélie Laguerre, Stuart F. Mcdaniel, Sarah Eppley, Elliott T. Gall, Todd Rosenstiel Apr 2022

Measuring Volatile Emissions From Moss Gametophytes: A Review Of Methodologies And New Applications, Danlyn L. Brennan, Leslie M. Kollar, Scott Kiel, Timea Deakova, Aurélie Laguerre, Stuart F. Mcdaniel, Sarah Eppley, Elliott T. Gall, Todd Rosenstiel

Center for Life in Extreme Environments Publications

Mosses inhabit nearly all terrestrial ecosystems and engage in important interactions with nitrogen-fixing microbes, sperm-dispersing arthropods, and other plants. It is hypothesized that these interactions could be mediated by biogenic volatile organic compounds (BVOCs). Moss BVOCs may play fundamental roles in influencing local ecologies, such as biosphere–atmosphere–hydrosphere communications, physiological and evolutionary dynamics, plant–microbe interactions, and gametophyte stress physiology. Further progress in quantifying the composition, magnitude, and variability of moss BVOC emissions, and their response to environmental drivers and metabolic requirements, is limited by methodological and analytical challenges. We review several sampling techniques with various analytical approaches and describe best practices …


Development Of A Ppg Sensor Array As A Wearable Device For Monitoring Cardiovascular Metrics, Jose Ignacio Rodriguez-Labra Apr 2022

Development Of A Ppg Sensor Array As A Wearable Device For Monitoring Cardiovascular Metrics, Jose Ignacio Rodriguez-Labra

Masters Theses

Wearable devices with integrated sensors for tracking human vitals are widely used for a variety of applications, including exercise, wellness, and health monitoring. Photoplethysmography (PPG) sensors use pulse oximetry to measure pulse rate, cardiac cycle, oxygen saturation, and blood flow by passing a light beam of variable wavelength through the skin and measuring its reflection. A multi-channel PPG wearable system was developed to include multiple nodes of pulse oximeters, each capable of using different wavelengths of light. The system uses sensor fusion along with a machine learning model to perform feature extraction of relevant cardiovascular metrics across multiple pulse oximeters …


Dynamic Maneuvers For Satellite On-Orbit Servicing Utilizing Novel Continuum Robotics: Development & Experimentation, Nathan Dalton Apr 2022

Dynamic Maneuvers For Satellite On-Orbit Servicing Utilizing Novel Continuum Robotics: Development & Experimentation, Nathan Dalton

Masters Theses

Robotic on-orbit servicing is a developing technology that seeks to increase the longevity and repairability of faulty or aging resident space objects. In this research, the development of a flexible continuum manipulator for a small satellite system that performs low-complexity on-orbit servicing or debris removal is presented. Derivations of manipulator kinematics are described in detail, a non-linear control scheme has been developed, and the accuracy and servicing applications for the prototype are evaluated and discussed. The manipulator has been tested on an air-bearing dynamics simulator, and the results are extensively analyzed. System recommendations and future work suggestions are presented.


Development And Characterization Of Magnesium Phosphate Cement Based Ultra-High Performance Concrete, Jihui Qin, Fumin Dai, Hongyan Ma, Xiaobing Dai, Zhen Li, Xingwen Jia, Jueshi Qian Apr 2022

Development And Characterization Of Magnesium Phosphate Cement Based Ultra-High Performance Concrete, Jihui Qin, Fumin Dai, Hongyan Ma, Xiaobing Dai, Zhen Li, Xingwen Jia, Jueshi Qian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims at the development of magnesium phosphate cement-based ultra-high performance concrete (MPC-UHPC). To this end, MPC paste phase was designed by using high magnesia-to-phosphate (M/P, 3.5) and low water-to-cement (W/C, 0.10–0.16) mass ratios, and certain amounts of ultra-fine fly ash (UFA, 5%–15%). Fresh and hardened properties, and microstructure of the developed MPC-UHPC were evaluated, and compared with those of conventional UHPC as well. Test results showed that lower W/C resulted in higher mechanical strengths and lower drying shrinkage, but the sharp decrease of workability and increase of autogenous shrinkage. At a constant W/C, the addition of UFA effectively …


Pumping Of Concrete: Understanding A Common Placement Method With Lots Of Challenges, Dimitri Feys, Geert De Schutter, Shirin Fataei, Nicos S. Martys, Viktor Mechtcherine Apr 2022

Pumping Of Concrete: Understanding A Common Placement Method With Lots Of Challenges, Dimitri Feys, Geert De Schutter, Shirin Fataei, Nicos S. Martys, Viktor Mechtcherine

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Several million cubic meters of concrete are pumped daily, as this technique permits fast concrete placement. Fundamental research has been performed and practical guidelines have been developed to increase the knowledge of concrete behavior in pipes. However, the pumping process and concrete behavior are not fully understood. This paper gives an overview of the current knowledge of concrete pumping. At first, the known physics governing the flow of concrete in pipes are introduced. A series of experimental techniques characterizing concrete flow behavior near a smooth wall to predict pressure-flow rate relationships are discussed, followed by recent developments in the use …


Effect Of Carbon Nanotube And Graphite Nanoplatelet On Composition, Structure, And Nano-Mechanical Properties Of C-S-H In Uhpc, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu Apr 2022

Effect Of Carbon Nanotube And Graphite Nanoplatelet On Composition, Structure, And Nano-Mechanical Properties Of C-S-H In Uhpc, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper studied the influence of carbon nanotube (CNT) and graphite nanoplatelet (GNP) used at 0 to 0.3%, by mass of binder, on composition, structure, and nano-mechanical characteristics of C-S-H of ultra-high performance concrete (UHPC). Hydration kinetics, pore structure, and mechanical properties of UHPC were also investigated. The non-proprietary UHPC was proportioned with 17% lightweight sand for internal curing. Test results indicated that the addition of 0.3% CNT or GNP led to approximately 20 MPa increase in compressive strengths of non-fibrous UHPC mortar and fibrous UHPC (2% steel fibers), compared to those prepared without any nanomaterial. Such enhancement is attributed …


Policy Strategies To Solve The U.S. Recycling Crisis, Flavia M. Scotto D'Antuono Apr 2022

Policy Strategies To Solve The U.S. Recycling Crisis, Flavia M. Scotto D'Antuono

Student Publications

Following China’s Operation National Sword in 2018, the politics and economics of recycling have increasingly come under scrutiny as many examine whether it remains a worthwhile endeavor. Differences across municipalities, changing prices of goods, contamination, mislabeling, and involvement by the plastics industry has further confused the issue. This paper examines to what extent a national recycling policy would be effective and what form it may take using several case studies - whether it be mandatory recycled content minimums, extended producer responsibility, or allowing the industry to phase out completely,


Evaluation Of Manual Infrared Brake Screening Technologies, Joseph Crabtree, Brian Beaven, Jennifer Walton Apr 2022

Evaluation Of Manual Infrared Brake Screening Technologies, Joseph Crabtree, Brian Beaven, Jennifer Walton

Kentucky Transportation Center Research Report

The purpose of this project was to install and operate two manual infrared (IR) brake screening systems at Kentucky inspection facilities to enhance the quality of Level 1 safety inspections. A radio button in the inspection software allowed enforcement personnel to indicate when the IR equipment was used to select a truck for inspection. This feature allowed a direct comparison of performance measures (e.g., number of violations identified per inspection, out-of-service rate, etc.) for IR-generated inspections versus all inspections.

The evaluation focused on inspections at the Lyon County site for a 60-day period during September and October 2021. Analysis of …


Radio-Frequency Interference Estimation For Multiple Random Noise Sources, Ling Zhang, Haochen Yang, Xiangrui Su, Qiaolei Huang, Jagan Rajagopalan, Deepak Pai, Chulsoon Hwang, Jun Fan Apr 2022

Radio-Frequency Interference Estimation For Multiple Random Noise Sources, Ling Zhang, Haochen Yang, Xiangrui Su, Qiaolei Huang, Jagan Rajagopalan, Deepak Pai, Chulsoon Hwang, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

As more compact designs and more assembled function modules are utilized in modern electronic devices, radio-frequency interference (RFI) source reconstruction is becoming more challenging because different noise sources may contribute simultaneously. This article presents a novel methodology to reconstruct multiple random noise sources on a real-world product, including several double-data-rate (DDR) memory modules and a high-speed connector. The DDR modules located beneath a heatsink cause random noise-like signals, which renders phase measurements challenging. An approach based on the tuned-receiver mode of a vector network analyzer is developed to measure the field phase from the random DDR signals, which can be …


Frequency Domain Modeling And Optimal Parameter Tuning Of Power Converters For Dynamic Analysis Of The Grid Integration Of Photovoltaic Systems, Hussein Abdulrazzaq Lafta Alameri Apr 2022

Frequency Domain Modeling And Optimal Parameter Tuning Of Power Converters For Dynamic Analysis Of The Grid Integration Of Photovoltaic Systems, Hussein Abdulrazzaq Lafta Alameri

Dissertations

Power electronic converters are essential devices for the effective interconnection of renewable energy sources to the power grid, such as DC-DC, DC-AC, and AC-DC converters. Therefore, power converter models that provide an accurate mathematical representation of their interconnection with other grid components are crucial for reliable transient and steady state analyses during normal or abnormal grid operating conditions.

This dissertation introduces a Laplace domain-based modeling approach for the study of transient converter-grid interactions. The proposed approach is based on the development of two-port admittance models of converters and other components, combined with the use of numerical Laplace transforms (NLT). The …