Digital Commons Network^™

Asphaltene Stability In Crude Oil During Carbon Dioxide Injection And Its Impact On Oil Recovery: A Review, Data Analysis, And Experimental Study, Sherif M. Fakher

Masters Theses

"Crude oils are usually associated with many compounds, some of which are favorable and others, which are not. One of the most unfavorable components of crude oil that pose severe operational problems and decreases oil production significantly are asphaltenes. These compounds are solids that are homogenized in the crude oil at room temperature but tend to separate from solution when agitated. They can deposit in the reservoir pores, wellbore, and transportation pipelines thus causing severe operational problems and oil recovery reduction.

Even though researchers have been studying asphaltenes for more than 100 years, there is still an ambiguity concerning asphaltene …

Archaeological Investigation Using Geophysical Methods To Locate Historic Byram's Ford Road, Marshall Seth Foster

Masters Theses

"Ground penetrating radar, a time domain electromagnetic metal detector and a frequency domain electromagnetic metal detector were used with the goal of locating a section of the Byram's Ford Road believed to be intersecting the historic Big Blue Battlefield in the Westport area of Kansas City, Missouri.

Ground penetrating data were acquired at three sites, Site A, Site B, and Site C. The time domain EM metal detector was used to acquire data at Site A, where subsequent ground truthing was conducted using the frequency domain EM metal detector and an excavation tool. Significant anomalies were visible on both the …

Routing Algorithm For The Ground Team In Transmission Line Inspection Using Unmanned Aerial Vehicle, Yu Li

Masters Theses

"With the rapid development of robotics technology, robots are increasingly used to conduct various tasks by utility companies. An unmanned aerial vehicle (UAV) is an efficient robot that can be used to inspect high-voltage transmission lines. UAVs need to stay within a data transmission range from the ground station and periodically land to replace the battery in order to ensure that the power system can support its operation. A routing algorithm must be used in order to guide the motion and deployment of the ground station while using UAV in transmission line inspection. Most existing routing algorithms are dedicated to …

Evolved Parameterized Selection For Evolutionary Algorithms, Samuel Nathan Richter

Masters Theses

"Selection functions enable Evolutionary Algorithms (EAs) to apply selection pressure to a population of individuals, by regulating the probability that an individual's genes survive, typically based on fitness. Various conventional fitness based selection functions exist, each providing a unique method of selecting individuals based on their fitness, fitness ranking within the population, and/or various other factors. However, the full space of selection algorithms is only limited by max algorithm size, and each possible selection algorithm is optimal for some EA configuration applied to a particular problem class. Therefore, improved performance is likely to be obtained by tuning an EA's selection …

Impact Of Framing And Base Size Of Computer Security Risk Information On User Behavior, Xinhui Zhan

Masters Theses

"This research examines the impact of framing and base size of computer security risk information on users' risk perceptions and behavior (i.e., download intention and download decision). It also examines individual differences (i.e., demographic factors, computer security awareness, Internet structural assurance, self-efficacy, and general risk-taking tendencies) associated with users' computer security risk perceptions. This research draws on Prospect Theory, which is a theory in behavioral economics that addresses risky decision-making, to generate hypotheses related to users' decision-making in the computer security context. A 2 x 3 mixed factorial experimental design (N = 178) was conducted to assess the effect of …

Advanced Techniques For Improving Canonical Genetic Programming, Adam Tyler Harter

Masters Theses

"Genetic Programming (GP) is a type of Evolutionary Algorithm (EA) commonly employed for automated program generation and model identification. Despite this, GP, as most forms of EA's, is plagued by long evaluation times, and is thus generally reserved for highly complex problems. Two major impacting factors for the runtime are the heterogeneous evaluation time for the individuals and the choice of algorithmic primitives. The first paper in this thesis utilizes Asynchronous Parallel Evolutionary Algorithms (APEA) for reducing the runtime by eliminating the need to wait for an entire generation to be evaluated before continuing the search. APEA is applied to …

Less Is More: Beating The Market With Recurrent Reinforcement Learning, Louis Kurt Bernhard Steinmeister

Masters Theses

"Multiple recurrent reinforcement learners were implemented to make trading decisions based on real and freely available macro-economic data. The learning algorithm and different reinforcement functions (the Differential Sharpe Ratio, Differential Downside Deviation Ratio and Returns) were revised and the performances were compared while transaction costs were taken into account. (This is important for practical implementations even though many publications ignore this consideration.) It was assumed that the traders make long-short decisions in the S&P500 with complementary 3-month treasury bill investments. Leveraged positions in the S&P500 were disallowed. Notably, the Differential Sharpe Ratio and the Differential Downside Deviation Ratio are risk …

Propagation Of Uncertainty Through Coning, Sculling, And Scrolling Corrections For Inertial Navigation, James Daniel Alan Brouk

Masters Theses

"This thesis investigates the propagation of estimation errors through generalized coning, sculling, and scrolling algorithms used in modern day inertial navigation systems, in order to accurately quantify the uncertainty in the estimation of position, velocity, and attitude. The corrections for coning, sculling, and scrolling algorithms have an often unaccounted for effect on documented and empirically derived error statistics for measurements used to predict the uncertainty in a vehicle's position, velocity, and attitude estimates. Through the development of an error analysis for these generalized algorithms, mappings of the measurement and estimation errors through the correction termare generated. Using the developed mappings, …

Cognitive Computing Meets The Internet Of Things, Zakaria Maamar, Thar Baker, Noura Faci, Emir Ugljanin, Yacine Atif, Mohammed Al-Khafajiy, Mohamed Sellami

All Works

This paper discusses the blend of cognitive computing with the Internet-of-Things that should result into developing cognitive things. Today's things are confined into a data-supplier role, which d ...

Geophysical Imaging Beneath Lake Chesterfield, Missouri, James Daniell Hayes

Masters Theses

"Lake Chesterfield in Wildwood, Missouri, has been leaking since construction of the earth-fill dam was completed in 1986, despite numerous mitigation efforts. The mitigation efforts, including the injection of grouting and the emplacement of clay liners, has not solve the leakage problem.

In the current study, geophysical (subsurface imaging) data was acquired across the drained and dry lake bed and along the base of the earth-fill dam to 1) map variable depth to top of bedrock, 2) determine the variable quality of the bedrock to depths on the order of 80 ft., 3) identify any significant karst features beneath the …

Design And Implementation Of Applications Over Delay Tolerant Networks For Disaster And Battlefield Environment, Karthikeyan Sachidanandam

Masters Theses

"In disaster/battlefield applications, there may not be any centralized network that provides a mechanism for different nodes to connect with each other to share important data. In such cases, we can take advantage of an opportunistic network involving a substantial number of mobile devices that can communicate with each other using Bluetooth and Google Nearby Connections API(it uses Bluetooth, Bluetooth Low Energy (BLE), and Wi-Fi hotspots) when they are close to each other. These devices referred to as nodes form a Delay Tolerant Network (DTN), also known as an opportunistic network. As suggested by its name, DTN can tolerate delays …

Combining Machine Learning And Metaheuristics Algorithms For Classification Method Proaftn, Feras Al-Obeidat, Nabil Belacel, Bruce Spencer

All Works

© Crown 2019. The supervised learning classification algorithms are one of the most well known successful techniques for ambient assisted living environments. However the usual supervised learning classification approaches face issues that limit their application especially in dealing with the knowledge interpretation and with very large unbalanced labeled data set. To address these issues fuzzy classification method PROAFTN was proposed. PROAFTN is part of learning algorithms and enables to determine the fuzzy resemblance measures by generalizing the concordance and discordance indexes used in outranking methods. The main goal of this chapter is to show how the combined meta-heuristics with inductive …

Multiphysics Prediction Model Of Microwave Curing For Thick Polymer Composites, Siva Dasari

Masters Theses

"Microwave curing technologies have many advantages over the traditional thermal curing methods for the manufacturing of fiber reinforced polymers, especially the processing speed and energy efficiency. Energy can be instantaneously transferred through applied electromagnetic fields and heat is generated based on dipolar rotational interactions. Microwave curing processes have been used for glass fiber composites but there are significant challenges associated with microwave curing of carbon fiber composites. Efficient heating may be difficult due to high dielectric loss associated with carbon fibers. Laminate quality will be highly dependent on the uniformity of the electromagnetic field in the material. In this work, …

U-Pb Detrital Zircon Geochronology Of Paleozoic Clastics Of The Ozark Plateau: Implication For Sea-Level Fluctuations And Far-Field Tectonics, Chen Zhao

Masters Theses

"The Ozark Plateau of south-central Missouri is underlain by Ordovician to Pennsylvanian carbonate and clastic strata. Enigmatic, presumably Pennsylvanian 'filled sink' structures are common on the Ozark Plateau and remain a source of controversy. We present results for U-Pb ages of detrital zircons for 13 samples from the OP. We use U-Pb ages from other Paleozoic clastics and 'filled sinks' on the OP, to suggest: 1) FSS record a period of Middle Ordovician erosion and sedimentation and 2) document significant shifts in sediment provenance that reflect regional tectonic events affecting the North American Craton.

The KDE plots of normalized detrital …

The Correlation Between Sleep And Lifespan In Drosophila Melanogaster, Joshua Randall Lisse

Masters Theses

”Adequate sleep is associated with an individual’s health. Too little sleep is associated with many health problems, including cardiovascular disease, obesity, and a general increase in all-cause mortality. Yet the molecular changes that link poor sleep and changes in health are still not well understood. Individuals have a unique daily need for sleep, and deviations from the animal’s regular sleeping patterns can be indicative of, or result in, underlying changes in its health. Therefore, we hypothesize that changes in the sleep architecture in Drosophila melanogaster reflect changes in the fly’s health.

We determined sleep architecture in wild-type male flies over …

Estimating Electromagnetic Emissions From A Site Installation With Multiple Racks Of Server Equipment, Ze Sun

Masters Theses

“There are hundreds, sometimes even thousands, of servers working simultaneously inside a data center. Their radiation can be a problem and cause EMI issues. However, it is not feasible to perform full-wave simulation of these racks because of the large electric size of the model. In this thesis, an algorithm is proposed to predict the emission form rack array. The equivalent dipole source is extracted from EMI measurement data of a single rack and used as the radiation source in the multiple rack model. The coupling between racks cannot be ignored, but through the simulation, it is also found that …

Dependence Measure For Length-Biased Survival Data Using Copulas, Rachid Bentoumi, Mhamed Mesfioui, Mayer Alvo

All Works

© 2019 Rachid Bentoumi et al., published by De Gruyter 2019. The linear correlation coefficient of Bravais-Pearson is considered a powerful indicator when the dependency relationship is linear and the error variate is normally distributed. Unfortunately in finance and in survival analysis the dependency relationship may not be linear. In such case, the use of rank-based measures of dependence, like Kendall's tau or Spearman rho are recommended. In this direction, under length-biased sampling, measures of the degree of dependence between the survival time and the covariates appear to have not received much intention in the literature. Our goal in this …

Pressure-Induced Structural Phase Transition And Electronic Structure Of In$_{1-X}$Ga$_{X}$P Alloys: A Dft Study, Kabita Khoirom, Indrajit Sharma, Brojen Singh, Ramkumar Thapa

Turkish Journal of Physics

We present the density functional calculation to study the pressure-induced structural phase transition and electronic structure of In$_{1-x}$Ga$_{x}$P ($x =$ 0.0, 0.25, 0.5, 0.75, 1) alloys. We report the optimized structural parameters such as lattice constant, bulk modulus, and derivative of the bulk modulus of the alloys. Our calculation confirms that the alloys in the zinc-blende structure are more stable than in the rock-salt structure. The phase transition study from zinc-blende to rock-salt under pressure shows that the transition pressure increases with an increase in doping concentration. The energy band diagram of the alloys in the zinc-blende phase reveals a …

Determination Of Effective Resonance Energies For The $^{185}$Re(N,$\Gamma )^{186}$Re And $^{187}$Re(N,$\Gamma )^{188}$Re Reactions By Cadmium Ratio Method, Mustafa Güray Budak

Turkish Journal of Physics

The effective resonance energy ($\bar{E}_{r})$ values for the $^{185}$Re(n,$\gamma )^{186}$Re and $^{187}$Re(n,$\gamma )^{188}$Re reactions were measured by using the cadmium ratio method. $^{197}$Au and $^{98}$Mo isotopes were selected as dual monitors to determine the epithermal neutron spectrum shape factor in the irradiation sites of a 37 GBq $^{241}$Am-Be neutron source. The analytical grade rhenium(VII) oxide samples were diluted with Al$_{2}$O$_{3}$ powder to reduce neutron self-shielding effects, and they were put into 1-mm thick small cylindrical polytetrafluoroethylene (PTFE) boxes. Samples were irradiated in a $^{241}$Am-Be neutron source. The activation produced in the irradiated samples was measured in close-counting geometry on the …

Higher-Order Differential Cross Section Calculation For The Associated Production Ofa W Boson And Jets In The Electron Decay Channel At A Center-Of-Mass Energy Of 13tev In Proton-Proton Collisions, Kadi̇r Öcalan

Turkish Journal of Physics

Higher-order cross sections for the production of a W boson in association with jets in the electron decay channel are presented in this study. Cross sections were calculated in a fully differential way using a computational framework based on proton-proton collisions at a center-of-mass energy of 13 TeV. The differential cross section predictions in the fiducial phase-space were compared at next-to-leading order (NLO) and next-to-NLO (NNLO) in perturbative quantum chromodynamics (pQCD). The differential results are reported for the variables including the jet multiplicity, the invariant mass of the W boson, transverse momentum, the jet rapidity, and the electron pseudorapidity that …

Electroweak Decays Of Unflavored Mesons In Poincaré Covariant Quark Model, Vadzim Haurysh, Viktor Andreev

Turkish Journal of Physics

This work presents the procedure for obtaining integral representation of the radiative decay constant in the Poincaré-covariant quark model, based on Poincaré-invariant quantum mechanics. In the course of the work the authors give numerical estimates of magnetic moments of the light quarks ($u,d,s$) from the $V\rightarrow P\gamma$ decay, based on the calculation method of the observer that was previously developed. This technique is generalized in the case of the decay $P\rightarrow V\gamma$ with further numerical calculation of mixing angles $\eta-\eta^{\prime}$ of pseudoscalar mesons. Within the framework of the offered approach, we obtain a self-consistent model that describes radiative and leptonic …

Effect Of Low-Temperature Oxidation On The Properties Of Tivn/Vn Multilayer Coatings, Merve Ertaş Uslu, Özge Doğan, Leyla Çolakerol Arslan

Turkish Journal of Physics

An extensive study of the surface oxidation process on the properties of TiVN/VN multilayer coatings deposited by RF magnetron sputtering on Mg alloys was performed. TiVN/VN multilayer coatings with a total thickness of 660 nm and different layer numbers of 5, 11, and 33 were oxidized by annealing at 450K under partial oxygen pressure. Electronic, mechanical, and tribological properties of these coatings were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscope, nanoindentation measurements, and scratch tester. The experimental results showed that the oxidation of TiVN/VN multilayer coatings leads to better performance in terms of surface roughness, hardness, and wear. …

The Influence Of Crosslinking Temperature On The Spectroscopic, Thermal, And Mechanical Properties Of Poly(Vinyl Alcohol)/Zeolite Composites, Cenk Denktaş

Turkish Journal of Physics

The aim of this study was to understand the effect of crosslinking temperature on the spectroscopic, thermal, and mechanical properties of poly(vinyl alcohol) (PVA)/zeolite composites. The PVA nanocomposite films were prepared using the solvent casting method with tartaric acid as the crosslinker. The changes in the structures of pure PVA film and powder clinoptilolite (CL) and nanocomposite films were analyzed by means of ATR-FTIR spectroscopy. The effect of both crosslinking temperature and CL on the composite films prepared by the addition of constant CL to the polymer matrix at different crosslinking temperatures (series II) and pure PVA films prepared with …

The Effect Of Phenylboronic Acid-Based Self-Assembled Monolayers On Theperformance Of Organic Field-Effect Transistors (Ofets), Tuğbahan Yilmaz Aliç

Turkish Journal of Physics

The dielectric/semiconductor interface is one of the most important components strongly affecting the performance of organic field-effect transistors (OFETs). To improve OFET parameters, we applied a series of phenylboronic acid derivatives as self-assembly molecules between dielectric and organic semiconductor layers. Device performance parameters, especially threshold voltage, current on/off ratio, and subthreshold slope, were improved. To elucidate the mechanism, dielectric/semiconductor interfaces were analyzed using atomic force microscope and contact angle techniques.

Nonlinear Frequency Conversion Of Light Inside A Microcavity, Emre Yüce

Turkish Journal of Physics

Changing the color of light in a small mode volume is essential for applications that require on-chip operation. Microcavities are profound structures given their property to confine light in a small mode volume. Here, I numerically investigate the frequency conversion of light in a microcavity and show that the frequency converted light intensity is distinguished from an open medium such as an optical fiber or a nonlinear crystal. I observe that the frequency converted light intensity increases with increased rate of change of the refractive index of the microcavity. Notably, this study shows that the intensity of the frequency converted …

Thin-Shell Wormholes From Kiselev Black Holes, Peter Kuhfittig

Turkish Journal of Physics

This paper discusses the theoretical construction of thin-shell wormholes from Kiselev black holes. We assume a barotropic equation of state for the exotic matter on the shell. While most of these wormholes are unstable to linearized radial perturbations, a limit argument is used to show that under certain conditions, stable solutions can be found.

Synthesis, Characterization, And Magnetic Properties Of Nanosizedzn0.5co0.5erxfe2-Xo4 Prepared By Coprecipitation Method, Zouheir Bitar, Doaa El-Said Bakeer, Ramadan Awad

Turkish Journal of Physics

In the present work, the effect of doping zinc cobalt ferrite by different concentrations of Er3+ on structural, optical, and magnetic properties was studied. Nanosized Zn0.5Co0.5ErxFe2-xO4 (0 ≤ x ≤ 0.2) was synthesized by the coprecipitation method. XRD analysis confirmed the formation of one phase face FCC spinel structure belonging to the Fd3m space group. TEM exhibited that the particle size decreased with the increase of Er3+ content, which is in agreement with XRD results. Two significant absorption bands from FTIR spectra were observed between 400 and 600 cm-1. The band gap energy value obtained from UV-Vis increased with the …

Method For Determination Of Water Hammer Conditions And Consequences Inpressurizers Of Nuclear Reactors, Vladimir Skalozubov, Oleg Chulkin, Denis Pirkovskiy, Igor Kozlov, Yuriy Komarov

Turkish Journal of Physics

Results of known experimental and computed studies of conditions for water hammers (WHs) in reactor pressurizers are analyzed. It is found that when emergency opening of pilot-operated safety valves of the pressurizers of nuclear reactors happens, WHs can be generated on pressurizer elements, and amplitudes of hydrodynamic load pulses significantly override the limiting values. An original method for determination of the WH conditions and consequences in the case of emergency filling of the pressurizers of nuclear reactors is proposed. Unlike the traditional Joukowski formula, the presented method considers the key features and effects of the WH conditions and consequences in …

Application Of The Fractional Oscillator Model To Describe Damped Vibrations, Sergo Rekhviashvili, Arsen Pskhu, Praveen Agarwal, Shilpi Jain

Turkish Journal of Physics

We consider a model of damped vibrations based on fractional differentiation. The model given is completely consistent with the classical model of vibration with viscous damping. We find the relation between the order of fractional differentiation in the equation of motion and Q-factor of an oscillator. The proposed approach seems more appropriate for the physical nature of the described system. The experiment with a vibrating piezoelectric plate, performed as part of the study, showed good agreement with the model and confirmed that the fractional oscillator model can be used to describe strongly damped vibrations.

Comparison Of Geometric And Drive-Induced Nonlinearities In Doubly Clamped,Thermoelastic Nanoelectromechanical Systems, Mehmet Seli̇m Hanay

Turkish Journal of Physics

The performance of resonant sensors based on nanoelectromechanical systems depends critically on the maximum amplitude of oscillation reached in the linear regime. The maximum linear amplitude is determined by nonlinear mechanisms that can originate from the material, geometric and transduction mechanism related factors. Here we compare the two competing effects, the geometric and drive-induced nonlinearities, for a commonly used device family, the thermoelastically driven, doubly clamped beams. We find that the geometric nonlinearity dominates for most of the device designs used in the literature, however the drive-induced nonlinearity becomes the determining factor for thicker beams with small electrode lengths.