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Data Augmentation For Improving Emotion Recognition In Software Engineering Communication, Mia Mohammad Imran, Yashasvi Jain, Preetha Chatterjee, Kostadin Damevski Sep 2022

Data Augmentation For Improving Emotion Recognition In Software Engineering Communication, Mia Mohammad Imran, Yashasvi Jain, Preetha Chatterjee, Kostadin Damevski

Computer Science Faculty Research & Creative Works

Emotions (e.g., Joy, Anger) are prevalent in daily software engineering (SE) activities, and are known to be significant indicators of work productivity (e.g., bug fixing efficiency). Recent studies have shown that directly applying general purpose emotion classification tools to SE corpora is not effective. Even within the SE domain, tool performance degrades significantly when trained on one communication channel and evaluated on another (e.g., Stack Overflow vs. GitHub comments). Retraining a tool with channel-specific data takes significant effort since manually annotating a large dataset of ground truth data is expensive. In this paper, we address this data scarcity problem by …

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Long-Time Kinetic Impact On Key Factors Affecting Asphaltene Precipitation, Ato Kwamena Quainoo, Abdulmohsin Imqam Sep 2022

Long-Time Kinetic Impact On Key Factors Affecting Asphaltene Precipitation, Ato Kwamena Quainoo, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The employment of predictive techniques combining kinetic and thermodynamic analyses is the succinct solution to effectively control asphaltene precipitation during crude oil production. Although thermodynamic processes and conditions have been well studied in the literature, the effect of long-time kinetics on the key factors affecting the precipitation of asphaltenes was not critically studied. This work employed a model oil for asphaltene precipitation long-time kinetic observations. Filtration and confocal microscopy experimentations for time periods of 0-7200 min were utilized to study asphaltene yields and sizes at room and high temperatures (25, 50, and 70 °C), rotation speeds (60 and 150 rpm), …

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Reliability Of Bridge Inspection Technologies, Glenn A. Washer Sep 2022

Reliability Of Bridge Inspection Technologies, Glenn A. Washer

INSPIRE Archived Webinars

This presentation will discuss the reliability of inspection technologies used for the condition assessment of highway bridges. Data from condition assessments are critical to asset management and decision-making. The methodologies used to assess condition are usually subjective methods, such as visual inspections, that can vary as a result of human factors and differences in training and interpretation of inspection procedures. Nondestructive evaluation technologies (NDE) are implemented on a more limited basis and rely on indirect measurements to infer the presence of damage, and these assessments are affected by environmental factors, materials variability, and limitations in the interpretation of the resulting …

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Study Of Asymptotic Velocity In The Bondi–Hoyle Accretion Flows In The Domain Of Kerr And 4-D Einstein–Gauss–Bonnet Gravities, Orhan Donmez, Fatih Dogan, Tuba Sahin Sep 2022

Study Of Asymptotic Velocity In The Bondi–Hoyle Accretion Flows In The Domain Of Kerr And 4-D Einstein–Gauss–Bonnet Gravities, Orhan Donmez, Fatih Dogan, Tuba Sahin

Materials Science and Engineering Faculty Research & Creative Works

Understanding the physical structures of the accreted matter very close to a black hole in quasars and active galactic nucleus (AGN) is an important milestone to constrain the activities occurring in their centers. In this paper, we numerically investigate the effects of the asymptotic velocities on the physical structures of the accretion disk around the Kerr and Einstein–Gauss–Bonnet (EGB) rapidly rotating black holes. The Bondi–Hoyle accretion is considered with a falling gas towards the black hole in an upstream region of the computational domain. Shock cones are naturally formed in the downstream part of the flow around both black holes. …

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Accelerated Bs/Ms Program In Electrical And Computer Engineering, Robert S. Woodley, Steve Eugene Watkins Sep 2022

Accelerated Bs/Ms Program In Electrical And Computer Engineering, Robert S. Woodley, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

The Electrical and Computer Engineering Department at Missouri University of Science and Technology implemented an Accelerated BS/MS Program in 2019. This program is designed to encourage and facilitate undergraduate majors in electrical and computer engineering to pursue a masters program. It is similar to engineering programs at other institutions that are identified with titles such as accelerated masters, combined BS/MS, and 4+1 options. It reduces the time needed for undergraduates to earn a graduate degree and exposes these students to research work. It provides a route for faculty to obtain quality graduate students and it builds enrollment for the department. …

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Some New Insights For Inferring Diapycnal (Irreversible) Diffusivity In Stably Stratified Turbulence, Amrapalli Garanaik, Subhas Karan Venayagamoorthy Sep 2022

Some New Insights For Inferring Diapycnal (Irreversible) Diffusivity In Stably Stratified Turbulence, Amrapalli Garanaik, Subhas Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

New insight for inferring diapycnal diffusivity in stably stratified turbulent flows is obtained based on physical scaling arguments and tested using high-resolution direct numerical simulation data. It is shown that the irreversible diapycnal diffusivity can be decomposed into a diapycnal length scale that represents an inner scale of turbulence and a diapycnal velocity scale. Furthermore, it is shown that the diapycnal length scale and velocity scale can be related to the measurable Ellison length scale (LE) that represents outer scale of turbulence and vertical turbulent velocity scale (w ′) through a turbulent Froude number scaling analysis. The turbulent Froude number …

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Be Smart, Save I/O: A Probabilistic Approach To Avoid Uncorrectable Errors In Storage Systems, Md Arifuzzaman, Masudul Bhuiyan, Mehmet Gumus, Engin Arslan Sep 2022

Be Smart, Save I/O: A Probabilistic Approach To Avoid Uncorrectable Errors In Storage Systems, Md Arifuzzaman, Masudul Bhuiyan, Mehmet Gumus, Engin Arslan

Computer Science Faculty Research & Creative Works

Silent data corruption poses a significant risk to the integrity of data in storage systems. Although error correction codes (ECC) can recover the majority of such errors, a nonnegligible portion of them escape ECC, referred as uncorrectable errors (UEs). Despite being rare in nature, increasing scale of storage systems and fast-growing I/O rates decreased the mean time between UEs from months to hours. Yet, unlike disk failures, UEs are hard to predict with high precision, making it difficult to adopt proactive measures. In this paper, we introduce a probabilistic approach to deploy UE mitigation strategies that can capture significant portion …

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Crystal Structure, Electronic Structure, And Optical Properties Of The Novel Li4cdge2s7, A Wide-Bandgap Quaternary Sulfide With A Polar Structure Derived From Lonsdaleite, Andrew J. Craig, Seung Han Shin, Jeong Bin Cho, Srikanth Balijapelly, Jordan C. Kelly, Stanislav S. Stoyko, Amitava Choudhury, Joon I. Jang, Jennifer A. Aitken, A. Sarjeant Sep 2022

Crystal Structure, Electronic Structure, And Optical Properties Of The Novel Li4cdge2s7, A Wide-Bandgap Quaternary Sulfide With A Polar Structure Derived From Lonsdaleite, Andrew J. Craig, Seung Han Shin, Jeong Bin Cho, Srikanth Balijapelly, Jordan C. Kelly, Stanislav S. Stoyko, Amitava Choudhury, Joon I. Jang, Jennifer A. Aitken, A. Sarjeant

Chemistry Faculty Research & Creative Works

The novel quaternary thiogermanate Li4CdGe2S7 (tetralithium cadmium digermanium heptasulfide) was discovered from a solid-state reaction at 750 °C. Single-crystal X-ray diffraction data were collected and used to solve and refine the structure. Li4CdGe2S7 is a member of the small, but growing, class of I4-II-IV2-VI7 diamond-like materials. The compound adopts the Cu5Si2S7 structure type, which is a derivative of lonsdaleite. Crystallizing in the polar space group Cc, Li4CdGe2S7 contains 14 crystallographically unique ions, all residing on …

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Study On Apparent Permeability Model For Gas Transport In Shale Inorganic Nanopores, Shuda Zhao, Hongji Liu, Enyuan Jiang, Nan Zhao, Chaohua Guo, Baojun Bai Sep 2022

Study On Apparent Permeability Model For Gas Transport In Shale Inorganic Nanopores, Shuda Zhao, Hongji Liu, Enyuan Jiang, Nan Zhao, Chaohua Guo, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Inorganic nanopores occurring in the shale matrix have strong hydrophilicity and irreducible water (IW) film can be formed on the inner surface of the pores making gas flow mechanisms in the pores more complex. In this paper, the existence of irreducible water (IW) in inorganic pores is considered, and, based on the Knudsen number (K (Formula presented.)) correction in shale pores, a shale gas apparent permeability model of inorganic nano-pores is established. The effect of the K (Formula presented.) correction on the apparent permeability, the ratio of flow with pore radius and the effect of IW on the apparent permeability …

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A Database Of Teleseismic Shear-Wave Splitting Measurements For The Ordos Block And Adjacent Areas, Lin Liu, Stephen S. Gao, Kelly H. Liu, Tu Xue, Yan Jia, Sanzhong Li Sep 2022

A Database Of Teleseismic Shear-Wave Splitting Measurements For The Ordos Block And Adjacent Areas, Lin Liu, Stephen S. Gao, Kelly H. Liu, Tu Xue, Yan Jia, Sanzhong Li

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Ordos block of the north China craton and its surrounding regions are affected by the India-Eurasia collision to the southwest and the subduction of the Pacific beneath the Eurasian plates to the east. To provide the foundation for delineating lithospheric deformation and asthenospheric flow beneath this tectonically diverse region, we have created a database of individual shear-wave splitting (SWS) parameters by applying a uniform set of data processing procedures. After automatic data processing and manual checking, a total of 16,228 pairs of well-defined PKS, SKKS, and SKS splitting parameters (fast orientations and splitting times) are obtained from 1023 broadband …

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Fabrications And Applications Of Micro/Nanofluidics In Oil And Gas Recovery: A Comprehensive Review, Junchen Liu, Yandong Zhang, Mingzhen Wei, Xiaoming He, Baojun Bai Sep 2022

Fabrications And Applications Of Micro/Nanofluidics In Oil And Gas Recovery: A Comprehensive Review, Junchen Liu, Yandong Zhang, Mingzhen Wei, Xiaoming He, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Understanding fluid flow characteristics in porous medium, which determines the development of oil and gas oilfields, has been a significant research subject for decades. Although using core samples is still essential, micro/nanofluidics have been attracting increasing attention in oil recovery fields since it offers direct visualization and quantification of fluid flow at the pore level. This work provides the latest techniques and development history of micro/nanofluidics in oil and gas recovery by summarizing and discussing the fabrication methods, materials and corresponding applications. Compared with other reviews of micro/nanofluidics, this comprehensive review is in the perspective of solving specific issues in …

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Nbt (No-Boundary Thinking): Needed To Attend To Ethical Implications Of Data And Ai, Joan Peckham, Andy Perkins, Tayo Obafemi-Ajayi, Xiuzhen Huang Aug 2022

Nbt (No-Boundary Thinking): Needed To Attend To Ethical Implications Of Data And Ai, Joan Peckham, Andy Perkins, Tayo Obafemi-Ajayi, Xiuzhen Huang

Electrical and Computer Engineering Faculty Research & Creative Works

In this era of Big Data and AI, expertise in multiple aspects of data, computing, and the domains of application is needed. This calls for teams of experts with different training and perspectives. Because data analysis can have serious ethical implications, it is important that these teams are well and deeply integrated. No-Boundary Thinking (NBT) teams can provide support for team formation and maintenance, thereby attending to the many dimensions of the ethics of data and analysis. In this NBT workshop session, we discuss the ethical concerns that arise from the use of data and AI, and the implications for …

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Superhard Single-Phase (Ti,Cr)B2 Ceramics, Lun Feng, William Fahrenholtz, Gregory E. Hilmas, Laura Silvestroni Aug 2022

Superhard Single-Phase (Ti,Cr)B2 Ceramics, Lun Feng, William Fahrenholtz, Gregory E. Hilmas, Laura Silvestroni

Materials Science and Engineering Faculty Research & Creative Works

A nominally pure and dense (Ti0.9Cr0.1)B2 ceramic was produced by spark plasma sintering of powders synthesized by boro/carbothermal reduction of oxides. The synthesized powders were a single phase and had an average particle of 0.4 ± 0.1 μm and an oxygen content of 1.2 wt%. Average Vickers hardness values of the resulting ceramics increased from 25.9 ± 0.8 GPa at a load of 9.81 N, to 46.3 ± 0.8 GPa at a load of 0.49 N. Compared to the nominally pure TiB2 ceramic obtained under the same processing conditions, the (Ti0.9Cr0.1)B2 ceramic had higher values under the same load due …

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Estimation Of Coal Density Using A 3d Imaging System: Rhovol, F. Nakhaei, Q. P. Campbell, M. Le Roux, S. Botlhoko Aug 2022

Estimation Of Coal Density Using A 3d Imaging System: Rhovol, F. Nakhaei, Q. P. Campbell, M. Le Roux, S. Botlhoko

Mining Engineering Faculty Research & Creative Works

The results of coal sink and float tests are plotted as washability curves. Analysis of these curves indicates the most effective method by which the coal can be cleaned. Sink and float experiments are sampling-dependent, destructive, and use toxic chemicals. The present research introduces an alternative method based on a 3D imaging system called RhoVol, in which the density of individual particles is determined from mass and volume measurements. A quantitative error analysis was conducted on coal sample density measurements obtained by RhoVol, and the main factors influencing the errors identified and investigated. The results show that the drawback of …

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Z-Source-Based High Step-Up Dc-Dc Converters For Photovoltaic Applications, Ramin Rahimi, Saeed Habibi, Mehdi Ferdowsi, Pourya Shamsi Aug 2022

Z-Source-Based High Step-Up Dc-Dc Converters For Photovoltaic Applications, Ramin Rahimi, Saeed Habibi, Mehdi Ferdowsi, Pourya Shamsi

Electrical and Computer Engineering Faculty Research & Creative Works

This article proposes three high step-up Z-source (ZS)-based dc-dc converters by integrating the conventional ZS network with switched-capacitor (SC) cells. The proposed converters offer a simple structure with a smooth input current, a high-voltage gain, and low voltage stress on the semiconductor devices. In addition, the proposed converters, unlike some existing ZS-based topologies in the literature, do not impose any limitation on the duty cycle of the power switch. These characteristics make the proposed converters excellent candidates to interface a low-voltage solar photovoltaic (PV) panel with a high-voltage dc bus in PV applications. Among the proposed three converters, the operating …

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Frame Of Reference Training For Content Analysis With Structured Teams (Fort-Cast): A Framework For Content Analysis Of Open-Ended Survey Questions Using Multidisciplinary Coders, Sandra J. Galura, Kristin A. Horan, Joy Parchment, Daleen Penoyer, Ann Schlotzhauer, Kenzie Dye, Emily Hill Aug 2022

Frame Of Reference Training For Content Analysis With Structured Teams (Fort-Cast): A Framework For Content Analysis Of Open-Ended Survey Questions Using Multidisciplinary Coders, Sandra J. Galura, Kristin A. Horan, Joy Parchment, Daleen Penoyer, Ann Schlotzhauer, Kenzie Dye, Emily Hill

Psychological Science Faculty Research & Creative Works

In the context of a global pandemic, the need for reliable analysis of qualitative data in healthcare has never been more pressing. Open-ended questions are a feasible way for both researchers and organizational stakeholders to gain deeper insight into complex situations when timely research is needed. However, the interpretation of brief, textual responses can prove problematic. Both manual and automated/semiautomated methods of coding qualitative data have been associated with errors and costly temporal delays. Data obtained from the qualitative analysis of open-ended questions have been questioned for lacking robust insights. The present article introduces an innovative, manual, team-based method of …

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Inducing Spin-Order With An Impurity: Phase Diagram Of The Magnetic Bose Polaron, Simeon I. Mistakidis, G. M. Koutentakis, F. Grusdt, P. Schmelcher, H. R. Sadeghpour Aug 2022

Inducing Spin-Order With An Impurity: Phase Diagram Of The Magnetic Bose Polaron, Simeon I. Mistakidis, G. M. Koutentakis, F. Grusdt, P. Schmelcher, H. R. Sadeghpour

Physics Faculty Research & Creative Works

We Investigate The Formation Of Magnetic Bose Polaron, An Impurity Atom Dressed By Spin-Wave Excitations, In A One-Dimensional Spinor Bose Gas. Within An Effective Potential Model, The Impurity Is Strongly Confined By The Host Excitations Which Can Even Overcome The Impurity-Medium Repulsion Leading To A Self-Localized Quasi-Particle State. The Phase Diagram Of The Attractive And Self-Bound Repulsive Magnetic Polaron, Repulsive Non-Magnetic (Fröhlich-Type) Polaron And Impurity-Medium Phase-Separation Regimes Is Explored With Respect To The Rabi-Coupling Between The Spin Components, Spin-Spin Interactions And Impurity-Medium Coupling. The Residue Of Such Magnetic Polarons Decreases Substantially In Both Strong Attractive And Repulsive Branches With Strong …

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Huber Kalman Filter For Wi-Fi Based Vehicle Driver's Respiration Detection, Yang Yang, Yunlong Luo, Alex Qi, Ge Shi, Miao Miao, Jun Fan, Jianhua Ma, Yihong Qi Aug 2022

Huber Kalman Filter For Wi-Fi Based Vehicle Driver's Respiration Detection, Yang Yang, Yunlong Luo, Alex Qi, Ge Shi, Miao Miao, Jun Fan, Jianhua Ma, Yihong Qi

Electrical and Computer Engineering Faculty Research & Creative Works

The use of breath detection in vehicles can reduce the number of vehicular accidents caused by drivers in poor physical condition. Prior studies of contactless respiration detection mainly targeted a static person. However, there are emerging applications to sense a driver, with emphasis on contactless methods. For example, being able to detect a driver's respiration while driving by using a vehicular Wi-Fi system can significantly enhance driving safety. The sensing system can be mounted on the back of the driver's seat, and it can sense the tiny chest displacement of the driver via Wi-Fi signals. The body displacement and car …

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Llam-Mdcnet For Detecting Remote Sensing Images Of Dead Tree Clusters, Zongchen Li, Ruoli Yang, Weiwei Cai, Yongfei Xue, Yaowen Hu, Liujun Li Aug 2022

Llam-Mdcnet For Detecting Remote Sensing Images Of Dead Tree Clusters, Zongchen Li, Ruoli Yang, Weiwei Cai, Yongfei Xue, Yaowen Hu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Clusters of dead trees are forest fires-prone. To maintain ecological balance and realize its protection, timely detection of dead trees in forest remote sensing images using existing computer vision methods is of great significance. Remote sensing images captured by Unmanned aerial vehicles (UAVs) typically have several issues, e.g., mixed distribution of adjacent but different tree classes, interference of redundant information, and high differences in scales of dead tree clusters, making the detection of dead tree clusters much more challenging. Therefore, based on the Multipath dense composite network (MDCN), an object detection method called LLAM-MDCNet is proposed in this paper. First, …

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Enhanced Supervised Descent Learning Technique For Electromagnetic Inverse Scattering Problems By The Deep Convolutional Neural Networks, He Ming Yao, Rui Guo, Maokun Li, Lijun Jiang, Michael Kwok Po Ng Aug 2022

Enhanced Supervised Descent Learning Technique For Electromagnetic Inverse Scattering Problems By The Deep Convolutional Neural Networks, He Ming Yao, Rui Guo, Maokun Li, Lijun Jiang, Michael Kwok Po Ng

Electrical and Computer Engineering Faculty Research & Creative Works

This work proposes a novel deep learning (DL) framework to solve the electromagnetic inverse scattering (EMIS) problems. The proposed framework integrates the complex-valued deep convolutional neural network (DConvNet) into the supervised descent method (SDM) to realize both off-line training and on-line 'imaging' prediction for EMIS. The offline training consists of two parts: 1) DConvNet training: the training dataset is created, and the proposed DConvNet is trained to realize the EM forward process and 2) SDM training: the trained DConvNet is integrated into the SDM framework, and the average descent directions between the initial prediction and the true label of SDM …

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A Millimeter-Wave Frequency-Reconfigurable Fabry-Pérot Cavity Antenna, Min Li, Muhammad Yasir Jamal, Xiaoqiang Li, Kwan Lawrence Yeung, Lijun Jiang, Tatsuo Itoh, Ross Murch Aug 2022

A Millimeter-Wave Frequency-Reconfigurable Fabry-Pérot Cavity Antenna, Min Li, Muhammad Yasir Jamal, Xiaoqiang Li, Kwan Lawrence Yeung, Lijun Jiang, Tatsuo Itoh, Ross Murch

Electrical and Computer Engineering Faculty Research & Creative Works

This letter introduces a method for implementing a frequency-reconfigurable Fabry-Pérot cavity (FPC) antenna utilizing polarization standing waves (PSWs). The PSW is supported by two metasurfaces (MSs) at cavity ends. The resonant condition allows the antenna to have frequency-reconfigurable characteristic by mechanically rotating the top MS around the center and relative to the bottom MS, without adjusting the physical dimension. The antenna is prototyped at 60 GHz for millimeter-wave applications. Simulated and measured results demonstrate that a tunable frequency range of 60.8-66.2 GHz with a maximum boresight gain of around 22.2 dBi can be attained, verifying the antenna concept.

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Optimization Of High-Speed Channel For Signal Integrity With Deep Genetic Algorithm, Huan Huan Zhang, Zhao Sheng Xue, Xin Yi Liu, Ping Li, Lijun Jiang, Guang Ming Shi Aug 2022

Optimization Of High-Speed Channel For Signal Integrity With Deep Genetic Algorithm, Huan Huan Zhang, Zhao Sheng Xue, Xin Yi Liu, Ping Li, Lijun Jiang, Guang Ming Shi

Electrical and Computer Engineering Faculty Research & Creative Works

A deep genetic algorithm (GA) is proposed to optimize the high-speed channel for signal integrity. In the traditional genetic algorithm-based high-speed channel optimization method, the eye height and eye width of the eye diagram are obtained by eye diagram simulation based on the full-wave algorithm, which is computationally expensive. In this letter, a deep neural network (DNN) is trained to predict the eye diagram information corresponding to a set of given design parameters of the high-speed channel. This DNN is embedded into the genetic algorithm to carry out the evaluation operation, which can greatly accelerate the evaluation process. A high-speed …

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Using Coherence And Interference To Study The Few Body Dynamics In Simple Atomic Collisions Systems, Sujan Bastola Aug 2022

Using Coherence And Interference To Study The Few Body Dynamics In Simple Atomic Collisions Systems, Sujan Bastola

Doctoral Dissertations

"Atomic Collision experiments are best suited to sensitively test the few-body dynamics of simple systems. The few-body dynamics, in turn, can be sensitively affected by interference effects. However, an important requirement to observe interference effects in atomic scattering experiments is that the incoming projectile beam must be coherent. The coherence properties of the incoming projectile can be controlled by the geometry of the collimating slit placed before the target. We performed a kinematically complete experiment where a 75 keV proton beam is crossed with a molecular hydrogen beam to study the dissociative capture process. The motivation for this project was …

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Hydroclimate Variability In Central America During The Holocene Inferred From Lacustrine Sediments In Lake Izabal, Eastern Guatemala, Edward Fernando Duarte Aug 2022

Hydroclimate Variability In Central America During The Holocene Inferred From Lacustrine Sediments In Lake Izabal, Eastern Guatemala, Edward Fernando Duarte

Doctoral Dissertations

"Holocene hydroclimate reconstructions have contributed to our understanding of the mechanisms controlling precipitation in Central America. Recent hydroclimate proxy records from the region, however, have revealed considerable spatiotemporal complexity in precipitation variability. This complexity is hypothesized to result from the interaction between multiple oceanic-atmospheric processes that converge in the region. This project analyzed three sediment cores from Lake Izabal, eastern lowland Guatemala, with the goal of understanding changes in precipitation, lake productivity, and lake water chemistry during the Holocene. Our proxy results indicate that precipitation in the region increased from the early to the middle Holocene, when Lake Izabal became …

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Studies Of Multiphase Distribution And Flow In Bubble/ Slurry Bubble Columns With /Without Internals And Advanced Sustainable Construction Materials Using Sophisticated Measurement Techniques, Omar Farid Aug 2022

Studies Of Multiphase Distribution And Flow In Bubble/ Slurry Bubble Columns With /Without Internals And Advanced Sustainable Construction Materials Using Sophisticated Measurement Techniques, Omar Farid

Doctoral Dissertations

"Bubble/slurry bubble columns have been widely studied and employed as multiphase flow reactors with and without vertical heat-exchanging tubes. In order to understand more deeply the effect of the dense internals on the hydrodynamics of bubble/slurry bubble column, systematic experiments were performed to visualize and quantify using the radioactive particle tracking (RPT) technique. A new methodology for implementing the radioactive particle tracking (RPT) technique has been developed to investigate the effect of the dense internals on the hydrodynamics of the bubble/slurry column reactor. Monte Carlo N-Particle (MCNP) simulation has been implemented to simulate the system to generate a large number …

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Social Media Analytics With Applications In Disaster Management And Covid-19 Events, Md Yasin Kabir Aug 2022

Social Media Analytics With Applications In Disaster Management And Covid-19 Events, Md Yasin Kabir

Doctoral Dissertations

"Social media such as Twitter offers a tremendous amount of data throughout an event or a disastrous situation. Leveraging social media data during a disaster is beneficial for effective and efficient disaster management. Information extraction, trend identification, and determining public reactions might help in the future disaster or even avert such an event. However, during a disaster situation, a robust system is required that can be deployed faster and process relevant information with satisfactory performance in real-time. This work outlines the research contributions toward developing such an effective system for disaster management, where it is paramount to develop automated machine-enabled …

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Secured Information Dissemination And Misbehavior Detection In Vanets, Ayan Roy Aug 2022

Secured Information Dissemination And Misbehavior Detection In Vanets, Ayan Roy

Doctoral Dissertations

"In a connected vehicle environment, the vehicles in a region can form a distributed network (Vehicular Ad-hoc Network or VANETs) where they can share traffic-related information such as congestion or no-congestion with other vehicles within its proximity, or with a centralized entity via. the roadside units (RSUs). However, false or fabricated information injected by an attacker (or a malicious vehicle) within the network can disrupt the decision-making process of surrounding vehicles or any traffic-monitoring system. Since in VANETs the size of the distributed network constituting the vehicles can be small, it is not difficult for an attacker to propagate an …

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Advanced Topologies Of High Step-Up Dc-Dc Converters For Renewable Energy Applications, Ramin Rahimi Aug 2022

Advanced Topologies Of High Step-Up Dc-Dc Converters For Renewable Energy Applications, Ramin Rahimi

Doctoral Dissertations

"This research is focused on developing several advanced topologies of high step-up DC-DC converters to connect low-voltage renewable energy (RE) sources, such as photovoltaic (PV) panels and fuel cells (FCs), into a high-voltage DC bus in renewable energy applications. The proposed converters are based on the combinations of various voltage-boosting (VB) techniques, including interleaved and quadratic structures, switched-capacitor (SC)-based voltage multiplier (VM) cells, and magnetically coupled inductor (CI) and built-in-transformer (BIT). The proposed converters offer outstanding features, including high voltage gain with low or medium duty cycle, a small number of components, low current and voltage stresses on the components, …

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Semiparametric Estimation With Clustered Right Censored Data Via Multivariate Gaussian Random Fields, Fathima Zahra Sainul Abdeen Aug 2022

Semiparametric Estimation With Clustered Right Censored Data Via Multivariate Gaussian Random Fields, Fathima Zahra Sainul Abdeen

Doctoral Dissertations

Consider a fixed number of clustered areas identified by their geographical coordinate that are monitored for the occurrences of an event such as pandemic, epidemic, migration to name a few. Data collected on units at all areas include time varying covariates and other environmental factors that may affect event occurrences. The event times in every area can be independent. They can also be correlated with correlation between two units induced by an unobservable frailty. In both cases, the collected data is considered pairwise to account for spatial correlation between all pair of areas. The pairwise right censored data is probit-transformed …

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Development Of Flood Prediction Models Using Machine Learning Techniques, Bhanu Kanwar Aug 2022

Development Of Flood Prediction Models Using Machine Learning Techniques, Bhanu Kanwar

Doctoral Dissertations

"Flooding and flash flooding events damage infrastructure elements and pose a significant threat to the safety of the people residing in susceptible regions. There are some methods that government authorities rely on to assist in predicting these events in advance to provide warning, but such methodologies have not kept pace with modern machine learning. To leverage these algorithms, new models must be developed to efficiently capture the relationships among the variables that influence these events in a given region. These models can be used by emergency management personnel to develop more robust flood management plans for susceptible areas. The research …

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