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2021

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Articles 3211 - 3240 of 9983

Full-Text Articles in Engineering

Fabrication And Characterization Of Polyvinylidene Fluoride Nanofibers For Energy Harvesting Applications, Jui Vitthal Kharade Aug 2021

Fabrication And Characterization Of Polyvinylidene Fluoride Nanofibers For Energy Harvesting Applications, Jui Vitthal Kharade

Theses and Dissertations

Miniaturization of portable devices demand a power source that does not require recharging or replacement. Piezoelectric energy harvesters are devices that harvest mechanical energy from environment and convert it into electrical energy thus being an ideal candidate for replacing batteries in small devices. Objective of this thesis is to fabricate an energy harvester with efficient energy conversion. In this thesis, the effect of fabricating mechanisms, solvents, and composites on polyvinylidene nanofibers are analysed in order to improve the piezoelectric response of the nanofibers. These nanofibers are then used for fabricating an energy harvester. The energy harvester is implemented in a …

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Electrical Characterization Of Conductive Concrete Containing Graphite Powder, K. I. M. Iqbal Aug 2021

Electrical Characterization Of Conductive Concrete Containing Graphite Powder, K. I. M. Iqbal

Theses and Dissertations

Electrically conductive concrete has various potential non-structural functions such as self-sensing, de-icing, and electromagnetic shielding. Since conductive concrete is a composite containing moisture and discrete conductive additives, its electrical properties are very complex. Understanding these properties is the fundamental requirement for developing its non-structural applications. In this research, graphite powder is used as a conductive additive with varying percentages (0% to 30%) by cement paste volume. Both AC impedance analysis and DC measurement are performed in both wet and dry conditions. The results show that the resistivity measured by DC are not consistent because of polarization before/during the measurement. On …

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Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha Aug 2021

Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha

Theses and Dissertations

Injection molding is one of the most popular techniques for global plastic production. With this automation technique, the plastic product can be manufactured at a low cost with a complex geometrical shape. A manufacturing process with the high productivity of an injection molding machine depends on molding pressure and temperature inside the mold cavity. In this research, an experimental work is performed to determine a process monitoring system using asynchronous data acquisition, through the incorporation of wired piezo-ceramic sensor to acquire pressure of injection molding system. This piezoelectric sensor is designed in such a way that, a Bluetooth device can …

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In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil Aug 2021

In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil

Theses and Dissertations

Primary objective of this research was to study the correlation between energy parameters (temperature, time and pressure) of spark plasma sintering (SPS) and design/structural properties (uniform distribution of elements, sever lattice distortion, density), indirectly proving consolidation of a stable High-entropy alloy (HEA) that consists of minimum of five elements. Therefore, powders of five principal elements (CuCrFeNiTi) and one minor element (Al) in near equimolar ratios were used for HEA consolidation using SPS but without mechanical alloying. Overall results demonstrated that the HEA was not generated using heterogenous solution of CuCrFeNiTiAl using SPS. This suggests that the mechanical alloying of CuCrFeNiTiAl …

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The Cyber Security Evaluation Of A Wireless And Wired Smart Electric Meter, Patrick Nnaji Aug 2021

The Cyber Security Evaluation Of A Wireless And Wired Smart Electric Meter, Patrick Nnaji

Theses and Dissertations

In this thesis, an Experimental cyber security evaluation of Wireless Smart Electric Meter has been performed under cyber security attacks. The security integrity of data collection from EPM 6100 Power Quality Wireless Smart Electric Meter under a wireless cyber-attack was evaluated. After which the security integrity of data collection from the same Wireless Smart Electric Meter was evaluated under a different configuration. In this Thesis, we tested three different smart meters for their connectivity under different cybersecurity attacks. We compared the security integrity of the three different smart meters to measure their response under different cybersecurity attacks.

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Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman Aug 2021

Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman

Theses and Dissertations

Printability is the ability to print a reproducible structure using the bioprinting technique. Constructing the relationships between printability and printing parameters of the extrusion printing process is difficult because of the presence of too many independent and inter-correlated factors. For this reason, it is necessary to identify and limit the number of significantly influential factors. In addition, Scaffold based blood vessel fabrication is a key challenge in 3D Bioprinting. As vascular smooth muscle cell (VSMCs) is a major component of blood vessels, the investigation of the behavior and orientation of VSMCs after printing is required to better understand the 3D …

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Investigation Of Cell Behavior In 3d Printed Lumen Structures For Capillary Regeneration, Victoria Jade Perez Aug 2021

Investigation Of Cell Behavior In 3d Printed Lumen Structures For Capillary Regeneration, Victoria Jade Perez

Theses and Dissertations

This thesis work successfully generated a coaxial printing setup and process to generate 3D printed tubules. A dual syringe pump mechanism was developed to print tubular structures to investigate cell behavior with a goal to generate future capillary beds. The mechanism involves the use of collagen–alginate tubules and the use of EDTA to increase the porosity of the tubule structures to study their interaction with media and incubation techniques as well as behavior and morphology. Tubules of 1.7% sodium alginate and 0.4% collagen I reacting with 3.2% CaCl2 solution proved to be more stable in both the printing process and …

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Production And Characterization Of Polyurethane Fibers By Forcespinning Method And Incorporation Of Luminiscense Nanoparticles, Sunanda Kumar Saha Aug 2021

Production And Characterization Of Polyurethane Fibers By Forcespinning Method And Incorporation Of Luminiscense Nanoparticles, Sunanda Kumar Saha

Theses and Dissertations

In this work, Polyurethane (PU) fine fiber nonwoven mats are generated using the Forcespinning® method. A detailed study focusing on the effect of PU concentration within solutions of N, N Dimethylformamide and the effect of relative humidity (RH) on fiber average diameter and fiber yield is presented. Solutions were prepared with 4 different concentrations, 14, 15, 16 and 17 wt% of PU. It was observed that as concentration of PU increases, average diameter shows a tendency to increase. Production of fibers with RH varying from X to X was analyzed. It was shown that higher RH is convenient for PU …

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Investigation Of The Effect Of Process Parameters By Taguchi Method On Structural And Electrical Properties Of Rf Magnetron Sputtered Sio2 & Psi On Si Substrate, Sajid Mahfuz Uchayash Aug 2021

Investigation Of The Effect Of Process Parameters By Taguchi Method On Structural And Electrical Properties Of Rf Magnetron Sputtered Sio2 & Psi On Si Substrate, Sajid Mahfuz Uchayash

Theses and Dissertations

In this work, Taguchi Signal-to-noise (S/N) analysis was applied to investigate the effect of varying three process parameters, namely- sputtering power, working pressure and Ar gas flow rate on the surface, morphological and electrical properties of the RF sputtered SiO2 and Boron doped pSi over Si substrate. The contribution of a particular process parameter on these properties was also inspected by applying Analysis of Variance (ANOVA). SiO2 and pSi thin films were fabricated over Si substrate using RF magnetron sputtering system. Three sets of inputs for the three mentioned process parameters were chosen for sputtering SiO2 and pSi thin films. …

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Effect Of Obesity On Knee Joint During Walking And Squatting, Simon Vasquez Iii Aug 2021

Effect Of Obesity On Knee Joint During Walking And Squatting, Simon Vasquez Iii

Theses and Dissertations

This paper analyzes the effect of obesity on the knee joints during squats. This was performed on 2 different subjects by having each squat 30 times at their decided comfortable depth to display some fatigue and effects on the knee joints. Using the VICON NEXUS and AMTI force plates equipment at The University of Texas at Rio Grande Valley Biomechanics Lab, the center of pressure, knee flexion angles, velocity, and ground reaction forces were calculated. The subjects performed the exercises with and without additional weight using a body vest and kettlebell. The ground reaction forces showed a significant increase in …

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Investigating Adoption Behavior Of Owned And Shared Autonomous Vehicles: An Updated Technology Acceptance Model, Yellitza Soto Aug 2021

Investigating Adoption Behavior Of Owned And Shared Autonomous Vehicles: An Updated Technology Acceptance Model, Yellitza Soto

Theses and Dissertations

Transportation systems will be likely transformed by the emergence of autonomous vehicles (AVs), either owned privately or used in a shared system (SAVs), which promise for safe, convenient, and efficient mobility, to name a few benefits to the society. The manifestation of (S)AV benefits, however, is still dubious due to the observed public reluctance, or at best neutrality, towards (S)AVs, especially SAVs. The public's perception towards these innovations is still unclear, therefore, a gap remains in the analysis of individuals’ behavioral intention (BI) to use AVs and SAVs. To fill that gap, this study uses a behavioral psychology method. Specifically, …

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Effect Of Deposition Conditions On Properties Of Molybdenum Back Electrode For Cu(In,Ga)Se2 Solar Cell And Cu(In,Ga)Se2 Performance Analysis Through Numerical Simulation, Meah Imtiaz Zulkarnain Aug 2021

Effect Of Deposition Conditions On Properties Of Molybdenum Back Electrode For Cu(In,Ga)Se2 Solar Cell And Cu(In,Ga)Se2 Performance Analysis Through Numerical Simulation, Meah Imtiaz Zulkarnain

Theses and Dissertations

In the first part of this research, the effect of the deposition conditions on properties of molybdenum thin-film were investigated to achieve desired characteristics for its application as the back electrode of Cu(In,Ga)Se2 solar cell. DC and RF magnetron sputtering modes were employed and two sputtering parameters namely, working pressure and sputtering power, were varied to determine the sputtering mode and the sputtering conditions best suited for Mo thin-films having required properties. Sputtered Mo samples were characterized to determine their structural and mechanical properties such as preferred growth orientation, crystallinity, grain size, dislocation density, adhesion, and micro strain, and electrical …

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Using Single-Molecule Dna Flow-Stretching Experiments To See The Effects Of Temperature And Viscosity, Fatema Tuz Zohra Aug 2021

Using Single-Molecule Dna Flow-Stretching Experiments To See The Effects Of Temperature And Viscosity, Fatema Tuz Zohra

Theses and Dissertations

Deoxyribonucleic acid (DNA) is a highly charged long and semi-flexible polymer of which length is much longer than cell dimensions at least by 1,000-folds. A long linear DNA turns into a crumpled structure to fit into a tiny cell volume by the process known as DNA compaction. In nature, DNA fits into the volume of the cell using DNA compaction by packaging genome material. Various types of protein are involved in DNA compaction. To experiment with various proteins as DNA compaction agents, DNA needs to be stretched out. In our thesis, the effect of temperature and buffer viscosity on DNA …

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Comparison Of Two Advanced Oxidation Processes For Their Production Of Hydroxyl Radicals And Evaluation Of A Uv/Ozone Aop At Varying Uv Fluence For Treating Diclofenac, Alexandra Cass Aug 2021

Comparison Of Two Advanced Oxidation Processes For Their Production Of Hydroxyl Radicals And Evaluation Of A Uv/Ozone Aop At Varying Uv Fluence For Treating Diclofenac, Alexandra Cass

Master's Theses

This study explores the efficacy of two advanced oxidation processes for generation of hydroxyl radicals to promote degradation of emerging contaminants. Drought and water shortage have become pressing issues caused by our world’s changing climate. Water reclamation and reuse are increasingly important options for relieving this water stress. Water reuse runs the risk of reintroducing recalcitrant compounds that can accumulate in our bodies and environment. Advanced treatment methods that degrade these compounds are vital to protect our health and the health of the environment while providing necessary water resources. Advanced oxidation processes (AOPs) have shown great promise for removing recalcitrant …

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Develop A Multi-Functional Green Pervious Concrete (Mgpc) Pavement With Polycyclic Aromatic Hydrocarbons (Pahs) Removal Function., Hong Shang Aug 2021

Develop A Multi-Functional Green Pervious Concrete (Mgpc) Pavement With Polycyclic Aromatic Hydrocarbons (Pahs) Removal Function., Hong Shang

Electronic Theses and Dissertations

Stormwater runoff induced Polycyclic Aromatic Hydrocarbons (PAHs) contaminant increasingly imperils the groundwater quality and the sustainable development of human society due to the potential carcinogenic risks. Pavement can be considered as the first line of defense for contaminant removal of the stormwater runoff. New construction materials with stormwater runoff quantity and quality control are in urgent demand for updating the existing pavement system. An innovative material called Multi-functional Green Pervious Concrete (MGPC) was developed in the department of Civil and Environmental Engineering at University of Louisville. This material uses organoclay as the amendment to enhance the PAHs removal capacity of …

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Internet Of Things Security Case Studies And Internet Of Things Core Service Comparions, Jaseong Koo Aug 2021

Internet Of Things Security Case Studies And Internet Of Things Core Service Comparions, Jaseong Koo

Electronic Theses, Projects, and Dissertations

This culminating project conducted an analysis of IoT security breach case studies. The analysis identified numerous vulnerable points: software failure, node tampering attack, eavesdropping, code injection, unauthorized access, social engineering attack, hardware exploitation, and node insertion. It therefor seems that even with the proper tests conducted on vulnerabilities to discover solutions, regular end users are unable to apply patches or other technical solutions to protect themselves. This project solely focuses on analyzing of comprehensive IoT security services that come with devices connected to home network. The devices are those provided by the big three: Amazon, Google, and Microsoft, on the …

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Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea Aug 2021

Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea

Electronic Theses and Dissertations

An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. …

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Bilateral Ground Reaction Force Jumping Asymmetry And Performance, Keith Painter Aug 2021

Bilateral Ground Reaction Force Jumping Asymmetry And Performance, Keith Painter

Electronic Theses and Dissertations

The prevalence of asymmetry in performance research has increased in recent years with mixed results. Much of the performance research has focused on unilateral jumping activities attempting to show relationships to other performance variables. However, bilateral ground reaction forces (bGRF) from jumps are more frequently assessed in athlete monitoring programs and the asymmetry from those jumps could be a simple addition to data already being collected. Research into bGRF asymmetries is lacking and no studies have addressed longitudinal changes. Additionally, research into the relationship of asymmetries to performance have infrequently used athletes. For these reasons, this dissertation will focus on …

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Biofiltration Application At Ethanol Plants: Analysis Of Aqueous Streams And Treatment Of Vocs, Katie Marie Mowat Aug 2021

Biofiltration Application At Ethanol Plants: Analysis Of Aqueous Streams And Treatment Of Vocs, Katie Marie Mowat

Department of Environmental Engineering: Theses and Other Student Research

The United States used 14.5 billion gallons of the biofuel ethanol in 2019 produced primarily (82%) in dry-mill corn ethanol plants. These plants produce volatile organic compounds (VOCs) — some of which are hazardous air pollutants (HAPs) — during production. Traditional treatment methods for gaseous emissions use a large quantity of water or natural gas. Thus, a bio-trickling filter (BTF) is considered an innovative alternative treatment method. A lab-scale BTF was used in this study to look at the effect of ethanol concentration and temperature on the treatment of a HAPs mixture. Gaseous and aqueous testing were performed on the …

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The Effects Of Ceria Loading On Three-Way Catalysts For Passive Scr Operation, Calvin R. Thomas, Josh A. Pihl, Vitaly Y. Prikhodko, Michelle K. Kidder, Jochen A. Lauterbach, Todd J. Toops Aug 2021

The Effects Of Ceria Loading On Three-Way Catalysts For Passive Scr Operation, Calvin R. Thomas, Josh A. Pihl, Vitaly Y. Prikhodko, Michelle K. Kidder, Jochen A. Lauterbach, Todd J. Toops

Faculty Publications

Passive SCR systems, which employ both a three-way catalyst and SCR catalyst, are effective for the reduction of nitrogen oxide (NOx) emissions from lean burn gasoline engines. However, questions remain regarding the effect of three-way catalyst formulations on their performance in these systems. Here, Pd/CeOx/Al2O3 catalysts with variable CeOx loading were synthesized, characterized, and evaluated to determine the effects of CeOx on catalyst performance. While a small amount of ceria was beneficial for promoting essential reactions, excess ceria was detrimental due to the increase in oxygen storage capacity. Additionally, insights into potential reaction pathways for NH3 production were determined.

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Mixing Optimization With Inward Flow Configuration Contra-Rotating Impeller, Baffle-Free Tank, P. Satjaritanun, J. R. Regalbuto, J. A. Regalbuto, N. Tippayawong, Sirivatch Shimpalee Aug 2021

Mixing Optimization With Inward Flow Configuration Contra-Rotating Impeller, Baffle-Free Tank, P. Satjaritanun, J. R. Regalbuto, J. A. Regalbuto, N. Tippayawong, Sirivatch Shimpalee

Faculty Publications

In this study, pitched-blade, contra-rotating impeller, baffle-free tank with opposing inward flow is optimized using various designs of mixers derived from the Taguchi method. Mixing efficiency and torque are used to find the optimal design for the different specific gravities of solid particles employing in both experiments and CFD simulations. The analysis of signal-to-noise ratio shows that the impeller clearance and diameter are significant factors on the fluid flow and thus the mixing efficiency. In this study, 27 cases were studied to determine and report the optimal design parameters. A combination of CFD simulation with a strong design of experiment …

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Microstructure And Microchemistry Of Laser Welds Of Irradiated Austenitic Steels, Yaqiao Wu, Megha Dubey Aug 2021

Microstructure And Microchemistry Of Laser Welds Of Irradiated Austenitic Steels, Yaqiao Wu, Megha Dubey

Materials Science and Engineering Faculty Publications and Presentations

This article investigates the integrity of laser welds on neutron irradiated, He-containing steels. Life extension of the current fleet of light water reactors could necessitate repair of cracks on irreplaceable internal components, but heat input of weld repairs exacerbates the problem by initiating He-induced cracking. Laser welding is a promising low-heat-input technology thought to limit the extent of He-induced cracking. In this study, we produce laser welds in a hot cell on AISI 304L stainless steel plates previously irradiated in the Experimental Breeder Reactor (EBR)-II. We select a systematic set of three specimens spanning fluences ~1–28 displacements per atom (dpa) …

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Learning And Exploiting Shaped Reward Models For Large Scale Multiagent Rl, Arambam James Singh, Akshat Kumar, Hoong Chuin Lau Aug 2021

Learning And Exploiting Shaped Reward Models For Large Scale Multiagent Rl, Arambam James Singh, Akshat Kumar, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Many real world systems involve interaction among large number of agents to achieve a common goal, for example, air traffic control. Several model-free RL algorithms have been proposed for such settings. A key limitation is that the empirical reward signal in model-free case is not very effective in addressing the multiagent credit assignment problem, which determines an agent's contribution to the team's success. This results in lower solution quality and high sample complexity. To address this, we contribute (a) an approach to learn a differentiable reward model for both continuous and discrete action setting by exploiting the collective nature of …

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Vehicle Routing: Review Of Benchmark Datasets, Aldy Gunawan, Graham Kendall, Barry Mccollum, Hsin-Vonn Seow, Lai Soon Lee Aug 2021

Vehicle Routing: Review Of Benchmark Datasets, Aldy Gunawan, Graham Kendall, Barry Mccollum, Hsin-Vonn Seow, Lai Soon Lee

Research Collection School Of Computing and Information Systems

The Vehicle Routing Problem (VRP) was formally presented to the scientific literature in 1959 by Dantzig and Ramser (DOI:10.1287/mnsc.6.1.80). Sixty years on, the problem is still heavily researched, with hundreds of papers having been published addressing this problem and the many variants that now exist. Many datasets have been proposed to enable researchers to compare their algorithms using the same problem instances where either the best known solution is known or, in some cases, the optimal solution is known. In this survey paper, we provide a list of Vehicle Routing Problem datasets, categorized to enable researchers to have easy access …

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Incorporating The 10th Edition Institute Of Traffic Engineers (Ite) Trip Generation Rates Into Virginia Department Of Transportation Guidelines, Kun Xie, Mecit Cetin, Hong Yang, Xiaomeng Dong Aug 2021

Incorporating The 10th Edition Institute Of Traffic Engineers (Ite) Trip Generation Rates Into Virginia Department Of Transportation Guidelines, Kun Xie, Mecit Cetin, Hong Yang, Xiaomeng Dong

Civil & Environmental Engineering Faculty Publications

The Institute of Transportation Engineers (ITE) released the Trip Generation (TG) 10th edition in 2017, which significantly updated its database, and some of its trip generation rates were substantially lower than those of earlier editions. This study aims to investigate the applicability of the TG 10th edition in various Virginia contexts and to recommend how to incorporate the TG 10th edition into state guidelines. The research team surveyed 31 state transportation agencies to obtain a clear understanding of current practices in the adoption of trip rates and trip estimation approaches. We systematically compared trip rates of TG 9th and 10th …

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A Fire Protection Life Safety Analysis Of Multipurpose Building, Dalower Hossain Aug 2021

A Fire Protection Life Safety Analysis Of Multipurpose Building, Dalower Hossain

Fire Protection Engineering: Culminating Experience Project Reports

The following report is a fire and hazard protection analysis of a new building. This new building is a multi-purpose building called MPB locates in Gazipur, Dhaka, Bangladesh. The prescriptive requirements set by the codes and standards used at time of construction of the building have been met. The building has been properly classified with respect to occupancy as S1, Group B and F-1 and construction Type I A Sprinklered. Appropriate designs for interior partitions and exterior wall have been identified. Interior finish requirements have been analyzed for a better understanding of aesthetics guidelines. Based on the sprinkler drawing calculations, …

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Development Of Quantitative Molecular Photoacoustic Imaging For Noninvasive Cancer Diagnostics, Cayla Zandbergen Aug 2021

Development Of Quantitative Molecular Photoacoustic Imaging For Noninvasive Cancer Diagnostics, Cayla Zandbergen

Dissertations and Theses (Open Access)

Traditional diagnostic imaging provides clinicians with anatomical information that guides both diagnosis and treatment planning; however, once a tumor has progressed enough to be visible, it has often reached an advanced stage. Molecular imaging techniques allow for real-time visualization of chemical and biological processes via imaging of specific biomarkers, which can facilitate detection of malignancies before they become visible. One biomarker of interest is blood oxygen saturation (SO2) due to its correlation with hypoxia, which is associated with increased tumor malignancy; some studies have also established SO2 as an independent biomarker of disease progression. Additionally, because cancerous …

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Microstructure, Mechanical Performance, And Corrosion Behavior Of Additively Manufactured Aluminum Alloy 5083 With 0.7 And 1.0 Wt% Zr Addition, Le Zhou, Holden Hyer, Jinfa Chang, Abhishek Mehta, Thinh Huynh, Yang Yang, Yongho Sohn Aug 2021

Microstructure, Mechanical Performance, And Corrosion Behavior Of Additively Manufactured Aluminum Alloy 5083 With 0.7 And 1.0 Wt% Zr Addition, Le Zhou, Holden Hyer, Jinfa Chang, Abhishek Mehta, Thinh Huynh, Yang Yang, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Effect of 0.7 wt% and 1.0 wt% of Zr alloying on the laser powder bed fused (LPBF) printability/buildability of AA5083 alloys was investigated by examination of the microstructure and mechanical property. General corrosion behavior of these Zr-modified AA5083 alloys produced by LPBF in 3.5 wt% NaCl solution was also examined and compared to the LPBF AlSi10Mg alloy and AA5083-H131 alloy. Unmodified AA5083 alloy produced by LPBF exhibited extensive solidification cracks, but alloying it with Zr mitigated the cracking due to the grain refinement from the formation of the primary L12-Al3Zr. Moreover, 1.0 wt% of Zr alloying …

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Effect Of Obesity On Walking To Running And Running To Walking Transitions, Salvador Baruch Alcorta Bautista Aug 2021

Effect Of Obesity On Walking To Running And Running To Walking Transitions, Salvador Baruch Alcorta Bautista

Theses and Dissertations

This work investigates human Walking to Running transition (WRT) and Running to Walking transition (RWT). The focus is to be able to identify the correct WRT and RWT phase jumps. This investigation uses experimental data from the VICON Motion Analysis System (MAS) and of the treadmill WRT and RWT trials. The musculoskeletal model consists of pelvis, femur, tibia, and foot. This investigation uses as reference the work reported in the literature by Diedricj and Warren.. For the calculations in this investigation Excel and Matlab are used to filter the data and calculate the relative phase jumps. This work reports the …

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Machinability Of Carbon Fiber Reinforced Polymer (Cfrp) Composites: Modeling And Optimization Using Taguchi Analysis And Multi-Objective Genetic Algorithm, S M Abdur Rob Aug 2021

Machinability Of Carbon Fiber Reinforced Polymer (Cfrp) Composites: Modeling And Optimization Using Taguchi Analysis And Multi-Objective Genetic Algorithm, S M Abdur Rob

Theses and Dissertations

Carbon Fiber Reinforced Polymer (CFRP) composites have been widely used in aerospace, automotive, nuclear, and biomedical industries due to their high strength to weight ratio, corrosion resistant durability and excellent thermo-mechanical properties in non-oxidative atmospheres. Machining of CFRP composites has always been a challenge for the manufacturers. In this study, turning operation has been performed on CFRP composites to investigate the effects of cutting parameters namely cutting speed, feed rate and depth of cut on the output characteristics including cutting force, surface roughness and tool wear using Taguchi Analysis. Regression Analysis has been used to develop mathematical model for cutting …

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