Physical Sciences and Mathematics Commons^™

Research And Development Of Optically Transparent Join With Low Processing Temperatures, Eric Kevin Muskovin

Masters Theses

The purpose of this study was to investigate durable solar cell cover glass joins produced by diffusion bonding with deep eutectic solvents (DES) and to develop a novel process of joining optically transparent materials at low temperatures. A joined PV cell-glass specimen was characterized using Raman, μ-FTIR, SEM-EDS, and thin-film XRD. DESs were created with malonic acid (MAL) and choline chloride (ChCl) of varying composition factors (CF; CF=MAL/ChCl). Joining borosilicate glass coupons was attempted using DESs with CF = 0.65 and 1 at temperatures between 100-150 °C for 20 hours. Joining the glass coupons failed at all temperatures and oxygen …

Analyzing Large Scale Trajectory Data To Identify Users With Similar Behavior, Tyler Clark Percy

Masters Theses

"In today's society, social networks are a popular way to connect with friends and family and share what's going on in your life. With the Internet connecting us all closer than ever before, it is increasingly common to use social networks to meet new friends online that share similar interests instead of only connecting with those you already know. For the problem of attempting to connect people with similar interests, this paper proposes the foundation for a Geo-social network that aims to extract the semantic meaning from users' location history and use this information to find the similarity between users. …

Bridge Deck Assessment Using Visual Inspection, Ground Penetrating Radar, Portable Seismic Property Analyzer-Ultrasonic Surface Wave, Hammer Sounding And Chain Drag, Abdullah Hadi Zaid Alhaj

Masters Theses

"Integrated non-destructive techniques were utilized to assess the condition of a reinforced concrete bridge deck. There were two main objectives accomplished.

The first objective was to assess the integrity of the reinforced concrete bridge deck using four non-destructive techniques, namely visual inspection, ground penetrating radar, portable seismic property analyzer-ultrasonic surface wave, and hammer sounding and chain drag. Visual inspection data were used to identify signs of deterioration on surface of the bridge deck such as cracking, concrete leaching, and reinforcement corrosion. Ground penetrating radar data were used to determine the relative condition of the bridge deck. However, due to the …

Application Of Seismic Attributes For 3-D Seismic Visualization Contributed In Structural And Stratigraphic Interpretation Of The Tangahoe And Farewell Formations In The Kupe Field, Taranaki Basin, New Zealand, Housam Hussein Grabeel

Masters Theses

"Taranaki Basin is a mainly offshore basin covering an area of approximately 100,000 km², elongated across the western margin of New Zealand's north island. However, the modern limit of the basin is extended toward the deep water to cover about 330,000 km². The basin is divided by tectonic activities into northern and southern grabens. The southern region has become the most extensively researched district in recent years as its prime lithology and structural trap distributions provide numerous hydrocarbon fields. One such field is the Kupe Field (256 km²), which lies on a northerly-plunging, reverse-faulted, …

Smart Augmented Reality Instructional System For Mechanical Assembly, Ze-Hao Lai

Masters Theses

"Quality and efficiency are pivotal indicators of a manufacturing company. Many companies are suffering from shortage of experienced workers across the production line to perform complex assembly tasks such as assembly of an aircraft engine. This could lead to a significant financial loss. In order to further reduce time and error in an assembly, a smart system consisting of multi-modal Augmented Reality (AR) instructions with the support of a deep learning network for tool detection is introduced. The multi-modal smart AR is designed to provide on-site information including various visual renderings with a fine-tuned Region-based Convolutional Neural Network, which is …

Classification Of Eeg Signals Of User States In Gaming Using Machine Learning, Chandana Mallapragada

Masters Theses

"In this research, brain activity of user states was analyzed using machine learning algorithms. When a user interacts with a computer-based system including playing computer games like Tetris, he or she may experience user states such as boredom, flow, and anxiety. The purpose of this research is to apply machine learning models to Electroencephalogram (EEG) signals of three user states -- boredom, flow and anxiety -- to identify and classify the EEG correlates for these user states. We focus on three research questions: (i) How well do machine learning models like support vector machine, random forests, multinomial logistic regression, and …

Modulated Photothermal Radiometry: Detector Sensitivity Study And Experimental Setup, Jessica Nicole Seals

Masters Theses

"This thesis outlines the development of a system used for determining the surface thermal diffusivity of both non-irradiated and irradiated materials. The motivation for this work is to establish a modulated photothermal radiometry (PTR) system on the campus of Missouri University of Science and Technology. One of the main efforts described in this thesis is the design and construction of the physical apparatus. Along the way, it was necessary to perform a detailed sensitivity analysis of the system to determine whether the expected signal emitted from the sample falls within the bounds of detectivity for the HgCdTe (MCT) detector used …

Salt Mobility Under Different Geological Regimes, Oznur Surek

Masters Theses

"This study investigates the evolution of Dan Salt Structure in the southern salt dome province, Danish Central Graben and Mars-Ursa Basin in the Northern Gulf of Mexico to understand salt and sediment interaction over time under different geologic regimes. An integration of structural and stratigraphic analyses is conducted to understand the relationship between halokinesis and sedimentation.

Interpretation of the seismic data in Dan Salt Structure shows that the structure has a complex geometry, which is divided into upper and lower parts. The evolutionary stage of both the upper and lower parts of the structure has been influenced by salt. The …

Improved Crpd Analysis And A Secure Scheduler Against Information Leakage In Real-Time Systems, Ying Zhang

Masters Theses

"Real-time systems are widely applied to the time-critical fields. In order to guarantee that all tasks can be completed on time, predictability becomes a necessary factor when designing a real-time system. Due to more and more requirements about the performance in the real-time embedded system, the cache memory is introduced to the real-time embedded systems.

However, the cache behavior is difficult to predict since the data will be loaded either on the cache or the memory. In order to taking the unexpected overhead, execution time are often enlarged by a certain (huge) factor. However, this will cause a waste of …

Multiscale Approaches Toward Advanced Lithium-Ion Battery: From Nano To Meso Scale, Susmita Sarkar

Masters Theses

“Battery performance and its degradation are determined by various aspects such as the transport of ions and electrons through heterogeneous internal structures composed of constituent particles, kinetic reactions at the interfaces, and a corresponding interplay between mechanical, chemical, and thermal responses. Further, modern battery materials require a variety of engineering processes such as coating, doping and mixing. As a result, in order to fully understand the behavior of the battery material and improve battery performance, it is necessary to understand and control the individual particle behavior and then connect it to the electrode. This study elucidated the physical phenomena associated …

Solidification Rate Detection Through Solid-Liquid Interface Tracking, Wei Luo

Masters Theses

”Studying the melt pool dynamics in laser powder bed fusion (LPBF) additive manufacturing is vital to predict the microstructure of the built part. High-speed synchrotron hard X-ray imaging is an advanced technique to monitor the LPBF process in situ and in real time. However, it is very challenging to track the solid-liquid interface due to the low image contrast, high image noise and unstable intensity of the image sequences.

In this paper, we propose an solid-liquid interface detector with human interaction to track the interface to compute the solidification rate of the melt pool. The proposed method includes six independent …

Tensorviz: Visualizing The Training Of Convolutional Neural Network Using Paraview, Xinyu Chen, Qiang Guan, Xin Liang, Li-Ta Lo, Simon Su, Trilce Estrada, James Ahrens

Computer Science Faculty Research & Creative Works

Deep Convolutional Networks have been very successful in visual recognition tasks recently. Previous works visualize learned features at different layers o help people to understand how CNNs learn visual recognition tasks. However they do not help to accelerate the training process. We use Paraview to provides both qualitative and quantitative visualization that help understand the learning procedure, tune the learning parameters and direct merging and pruning of neural networks.

Tensorviz: Visualizing The Training Of Convolutional Neural Network Using Paraview (Poster), Xinyu Chen, Qiang Guan, Xin Liang, Li-Ta Lo, Simon Su, Trilce Estrada, James Ahrens

Computer Science Faculty Research & Creative Works

Deep Convolutional Networks have been very successful in visual recognition tasks recently. Lots of previous works aimed to help people to get senses of why those biology-inspired networks achieved such good performances. Deconvnet[1], Guided propagation[2] and a comprehensive visualization tool box[3] can help people to see features learned at different layers of the networks. These works in some extent provided understanding and support for the biology origin of how convolutional networks emulate visual recognition tasks. However, due to the complexity of searching in very high dimensional parameter space, the whole training remains in black-boxes. Normally a large network needs weeks …

Estimating The Contribution Of Dynamical Ejecta In The Kilonova Associated With Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The source of the gravitational-wave (GW) signal GW170817, very likely a binary neutron star merger, was also observed electromagnetically, providing the first multi-messenger observations of this type. The two-week-long electromagnetic (EM) counterpart had a signature indicative of an r-process-induced optical transient known as a kilonova. This Letter examines how the mass of the dynamical ejecta can be estimated without a direct electromagnetic observation of the kilonova, using GW measurements and a phenomenological model calibrated to numerical simulations of mergers with dynamical ejecta. Specifically, we apply the model to the binary masses inferred from the GW measurements, and use the …

Nematic Topological Superconducting Phase In Nb-Doped Bi₂Se₃, Junying Shen, Wen-Yu He, Noah Fan Qi Yuan, Zengle Huang, Chang-Woo Cho, Seng Huat Lee, Yew San Hor, Kam Tuen Law, Rolf Lortz

Physics Faculty Research & Creative Works

A nematic topological superconductor has an order parameter symmetry, which spontaneously breaks the crystalline symmetry in its superconducting state. This state can be observed, for example, by thermodynamic or upper critical field experiments in which a magnetic field is rotated with respect to the crystalline axes. The corresponding physical quantity then directly reflects the symmetry of the order parameter. We present a study on the superconducting upper critical field of the Nb-doped topological insulator Nb_xBi₂Se₃ for various magnetic field orientations parallel and perpendicular to the basal plane of the Bi₂Se₃ layers. The …

Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The 410 and 660 km discontinuities (d410 and d660, respectively) beneath Alaska and adjacent areas are imaged by stacking 75,296 radial receiver functions recorded by 438 broadband seismic stations with up to 30 years of recording period. When the 1-D IASP91 Earth model is used for moveout correction and time depth conversion, significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of the d410 and d660 for the entire study area is 417 ± 12 km and 665 ± 12 km, respectively, and the mean mantle transition zone (MTZ) …

Ab Initio Structural Studies Of Cyclobutylmethyl Cations: Effect Of Fluoroalkyl Groups On The Relative Stability Of The Carbocations, Prakash Reddy, Golam Rasul, G. K. Surya Prakash

Chemistry Faculty Research & Creative Works

Ab initio calculations at MP2/cc-pVTZ level show that the trifluoromethyl group has a strong destabilizing effect on the nonclassical, σ-bridged cyclobutylmethyl cations. The GIAO-MP2 derived ¹³C NMR chemical shifts indicate substantial charge delocalization from the neighboring cyclobutyl ring for carbocations with an α-fluorolkyl group as compared to the 1-cyclobutylethyl cation, and this enhanced charge delocalization in case of the α-(trifluoromethyl)cyclobutylmethyl cation would lead to the ring-opening rearrangement to form the relatively more stable nonclassical primary cyclobutylmethyl cation, in which the carbocation center is farthest from the strongly electron-withdrawing trifluoromethyl group.

First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars …

Many-Body Quantum Dynamics In The Decay Of Bent Dark Solitons Of Bose-Einstein Condensates, Garyfallia C. Katsimiga, Simeon I. Mistakidis, G. M. Koutentakis, P. G. Kevrekidis, P. Schmelcher

Physics Faculty Research & Creative Works

The Beyond Mean-Field (MF) Dynamics Of A Bent Dark Soliton (BDS) Embedded In A Two-Dimensional Repulsively Interacting Bose-Einstein Condensate Is Explored. We Examine The Case Of A Single BDS Comparing The MF Dynamics To A Correlated Approach, The Multi-Configuration Time-Dependent Hartree Method For Bosons. Dynamical Snaking Of This Bent Structure Is Observed, Signaling The Onset Of Fragmentation Which Becomes Significant During The Vortex Nucleation. In Contrast To The MF Approximation 'filling' Of The Vortex Core Is Observed, Leading In Turn To The Formation Of Filled-Core Vortices, Instead Of The MF Vortex-Antivortex Pairs. The Resulting Smearing Effect In The Density Is …

Gw170608: Observation Of A 19 Solar-Mass Binary Black Hole Coalescence, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

On 2017 June 8 at 02:01:16.49 UTC, a gravitational-wave (GW) signal from the merger of two stellar-mass blackholes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with a network signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with component masses of 12⁺⁷ _-2M⊙⁺²_-2M⊙ (90% credible intervals). These lie in the range of measured black hole masses in low-mass X-ray binaries, thus allowing us to compare black holes detected through GWs with electromagnetic observations. The source's luminosity distance is 340⁺¹⁴⁰ _-140 corresponding to redshift -0.07 …

The Stripe 82 Massive Galaxy Project. Iii. A Lack Of Growth Among Massive Galaxies, Kevin Bundy, Alexie Leauthaud, Shun Saito, Claudia Maraston, David A. Wake, Daniel Thomas

Physics Faculty Research & Creative Works

The average stellar mass (M_*) of high-mass galaxies (log M_*/M_⊙ > 11.5) is expected to grow by ∼30% since z ~ 1, largely through ongoing mergers that are also invoked to explain the observed increase in galaxy sizes. Direct evidence for the corresponding growth in stellar mass has been elusive, however, in part because the volumes sampled by previous redshift surveys have been too small to yield reliable statistics. In this work, we make use of the Stripe 82 Massive Galaxy Catalog (S82-MGC) to build a mass-limited sample of 41,770 galaxies log M_*/M_{⊙ …}

On The Progenitor Of Binary Neutron Star Merger Gw170817, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

On 2017 August 17 the merger of two compact objects with masses consistent with two neutron stars was discovered through gravitational-wave (GW170817), gamma-ray (GRB 170817A), and optical (SSS17a/AT 2017gfo) observations. The optical source was associated with the early-type galaxy NGC 4993 at a distance of just ∼40 Mpc, consistent with the gravitational-wave measurement, and the merger was localized to be at a projected distance of ∼2 kpc away from the galaxy's center. We use this minimal set of facts and the mass posteriors of the two neutron stars to derive the first constraints on the progenitor of GW170817 at the …

Identification Of Aspergillus Fumigatus Udp-Galactopyranose Mutase Inhibitors, Julia S.Martin Del Campo, Meital Eckshtain-Levi, Nancy J. Vogelaar, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Aspergillus fumigatus is an opportunistic human pathogen responsible for deadly, invasive infections in immunocompromised patients. The A. fumigatus cell wall is a complex network of polysaccharides among them galactofuran, which is absent in humans. UDP-galactopyranose mutase (UGM) catalyzes the conversion of UDP-galactofuranose (UDP-Galf) to UDP-galactopyranose (UDP-Galp) and is an important virulence factor. UGM is a flavin-dependent enzyme that requires the reduced flavin for activity; flavin reduction is achieved by reaction with NADPH. The aim of this work was to discover inhibitors of UGM by targeting the NADPH binding site using an ADP-TAMRA probe in a high-throughput screening assay. The flavonoids …

First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100 Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7 …

Long-Range Interactions For Hydrogen: 6p-1s And 6p-2s Systems, Ulrich D. Jentschura, Chandra M. Adhikari

Physics Faculty Research & Creative Works

The collisional shift of a transition constitutes an important systematic effect in highprecision spectroscopy. Accurate values for van der Waals interaction coefficients are required in order to evaluate the distance-dependent frequency shift. We here consider the interaction of excited hydrogen 6P atoms with metastable atoms (in the 2S state), in order to explore the influence of quasi-degenerate 2P and 6S states on the dipole-dipole interaction. The motivation for the calculation is given by planned high-precision measurements of the transition. Due to the presence of quasi-degenerate levels, one can use the non-retarded approximation for the interaction terms over wide distance ranges.

Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The mantle transition zone (MTZ) discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System are imaged by stacking over 7,100 receiver functions. The mean thickness of the MTZ beneath the Western Branch and Tanzania Craton is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an up to 30 km thinning of the MTZ is observed and is attributable to upwelling of higher temperature materials from either the upper MTZ …

A Prograding Margin During Global Sea-Level Maxima: An Example From Mahajanga Basin, Northwest Madagascar, Jonathan Obrist-Farner, Philip J. Ball, Thomas A. (Mac) Mcgilvery, Raymond R. Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Mesozoic shelf margin in the Mahajanga Basin, northwest Madagascar, provides an example where inherited palaeobathymetry, coupled with sea-level changes, high sediment supply and fluctuations in accommodation influenced the stacking patterns and geometry of clinoforms that accreted onto a passive rifted margin. Two-dimensional (2D) seismic profiles are integrated with existing field data and geological maps to study the evolution of the margin. The basin contains complete records of transgression, highstand, regression and lowstand phases that took place from Jurassic to Cretaceous. Of particular interest is the Cretaceous, Albian to Turonian (ca. 113-93 Ma), siliciclastic shelf margin that prograded …

Convergence Analysis And Error Estimates For A Second Order Accurate Finite Element Method For The Cahn–Hilliard–Navier–Stokes System, Amanda E. Diegel, Cheng Wang, Xiaoming Wang, Steven M. Wise

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we present a novel second order in time mixed finite element scheme for the Cahn–Hilliard–Navier–Stokes equations with matched densities. the scheme combines a standard second order Crank–Nicolson method for the Navier–Stokes equations and a modification to the Crank–Nicolson method for the Cahn–Hilliard equation. in particular, a second order Adams-Bashforth extrapolation and a trapezoidal rule are included to help preserve the energy stability natural to the Cahn–Hilliard equation. We show that our scheme is unconditionally energy stable with respect to a modification of the continuous free energy of the PDE system. Specifically, the discrete phase variable is shown …

Air-Oxidation Of Phenolic Resin Aerogels: Backbone Reorganization, Formation Of Ring-Fused Pyrylium Cations, And The Effect On Microporous Carbons With Enhanced Surface Areas, Hojat Majedi Far, Suraj Donthula, Tahereh Taghvaee, Adnan Malik Saeed, Zachary Garr, Chariklia Sotiriou-Leventis, Nicholas Leventis

Chemistry Faculty Research & Creative Works

This paper is a thorough investigation of the chemical transformations during pyrolytic conversion of phenolic resins to carbons, and reports that all carbons obtained from main-stream phenolic resins including phloroglucinol-formaldehyde (FPOL), phloroglucinol-terephthalaldehyde (TPOL), resorcinol-formaldehyde (RF), and phenol-formaldehyde (PF) contain fused pyrylium rings and charge-compensating phenoxides. Those four phenolic resins were prepared via a fast HCl-catalyzed process as low-density nanostructured solids classified as aerogels, which, owing to their open porosity, allowed air circulation through their bulk. In that regard, the first step of this study was the air-oxidation of those phenolic resin aerogels at 240 °C. In FPOL and TPOL aerogels, …

Design The Capacity Of Onsite Generation System With Renewable Sources For Manufacturing Plant, Xiao Zhong, Md Monirul Islam, Haoyi Xiong, Zeyi Sun

Computer Science Faculty Research & Creative Works

The utilization of onsite generation system with renewable sources in manufacturing plants plays a critical role in improving the resilience, enhancing the sustainability, and bettering the cost effectiveness for manufacturers. When designing the capacity of onsite generation system, the manufacturing energy load needs to be met and the cost for building and operating such onsite system with renewable sources are two critical factors need to be carefully quantified. Due to the randomness of machine failures and the variation of local weather, it is challenging to determine the energy load and onsite generation supply at different time periods. In this paper, …