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Nanocrystalline Nio Structure: Preferred Oriented Growthnanocrystalline Nio Structure: Preferred Oriented Growth, Ali Rahmati, Soheila Mardani

Turkish Journal of Physics

Nickel oxide (NiO) nanostructures were deposited on Si (100), potassium bromide (KBr), and glass slide substrates at room temperature by the evaporation technique. The prepared samples were annealed at temperatures of 400 $^{\circ}$C and 600 $^{\circ}$C in air atmosphere. The structure, morphology, crystalline phase, optical properties, and chemical bonding of nanocrystalline nickel oxide were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-visible absorption spectrum, and FT-IR spectroscopy. XRD results and SEM images showed that nickel oxide nanoparticles have preferred orientation with uniform size distribution. The as-deposited films showed preferred orientation (texture) growth. As the films were annealed, the …

External Magnetic Field Effect On Bifacial Silicon Solar Cell''S Electric Power And Conversion Efficiencyexternal Magnetic Field Effect On Bifacial Silicon Solar Cell''S Electric Power And Conversion Efficiency, Issa Zerbo, Martial Zoungrana, Idrissa Sourabie, Adama Ouedraogo, Bernard Zouma, Dieudonne Joseph Bathiebo

Turkish Journal of Physics

This article presents a modelling study of external magnetic field effect on a bifacial silicon solar cell's electric power and conversion efficiency. After the resolution of the magnetotransport equation and continuity equation of excess minority carriers, we calculate the photocurrent density and the photovoltage and then we deduce the solar cell's electric power before discussing the influence of the magnetic field on those electrical parameters. Using the electric power curves versus junction dynamic velocity we determine the maximum electric power, the operating point of the solar cell, and the conversion efficiency according to magnetic field intensity. The numerical data show …

Dust-Ion Acoustic Shock Waves For Nonplanar Geometry With Nonthermal Electrons And Adiabatic Dusty Plasmadust-Ion Acoustic Shock Waves For Nonplanar Geometry With Nonthermal Electrons And Adiabatic Dusty Plasma, Louis Ete Akpabio

Turkish Journal of Physics

The nonplanar Burgers' equation for dust-ion-acoustic shock waves was derived for unmagnetized adiabatic dusty plasmas, comprising static negatively charged dust fluid, nonthermal distributed electrons, and Boltzmann distributed positron and adiabatic ion fluid, by employing the standard reductive perturbation method. The solution of the modified Burgers' equation for nonplanar geometry is numerically analyzed. The dependence of dust-ion-acoustic shock waves on some plasma parameters is explored. It is observed that inclusion of the nonthermal electron distribution modifies the shock wave profile significantly. Likewise, it is found that the nonplanar geometry effects have an important role on the establishment of shock waves. It …

Two Common Terminological Mistakes In Scientific Paperstwo Common Terminological Mistakes In Scientific Papers, Şaki̇r Erkoç

Turkish Journal of Physics

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Estimation Of Tip-Sample Force In Tapping Mode Atomic Force Microscopy Using Neural-Network And Repetitive Control Approaches, Alireza Toghraee

Masters Theses

"Atomic Force Microscopy is one of the most powerful tools for imaging, measuring and manipulating materials at nanometer scale. Among different modes of AFM, tapping mode, in which the oscillating tip touches the sample periodically, is most common mode. During the tip approach and retract, the tip interacts with sample and experiences different force regimes. This tip-sample interaction force contains information about the sample topology, material properties and tip geometry. However, quantitative measurement of the time-varying tip-sample interaction forcing function is challenging in the tapping mode because of the combined dynamic complexities of the cantilever and nonlinear complexity of the …

Determination Of Heavy Metals Concentration In Traditional Herbs Commonly Consumed In The United Arab Emirates, Rania Dghaim, Safa Al Khatib, Husna Rasool, Munawwar Ali Khan

All Works

Copyright © 2015 Rania Dghaim et al. Herbs are extensively consumed in the United Arab Emirates for their flavoring and medicinal properties. This study aimed at determining the concentration of heavy metals in selected traditional herbs consumed in the United Arab Emirates (UAE). A total of 81 samples of seven herbs, parsley (Petroselinumcrispum), basil (Ocimum basilicum), sage (Salvia officinalis), oregano (Origanum vulgare), mint (Mentha spicata), thyme (Thymus vulgaris), and chamomile (Matricaria chamomilla), were purchased from the local market in Dubai and analyzed for their cadmium, lead, copper, iron, and zinc contents. Microwave-assisted digestion was applied for the dissolution of the …

Distributed Computing And Artificial Intelligence, 12th International Conference, Sigeru Omatu, Qutaibah M. Malluhi, Sara Rodríguez González, Grzegorz Bocewicz, Edgardo Bucciarelli, Gianfranco Giulioni, Farkhund Iqbal

All Works

No abstract provided.

Experimental Study Of Crude Oil Emulsion Stability By Surfactants And Nanoparticles, Zainab Alabdulmohsen

Masters Theses

"Surfactants and nanoparticles are materials being widely used for enhanced oil recovery (EOR). Surfactants are mainly used to reduce the interfacial tension between oil and water which could form a stable film of emulsion between these two immiscible fluids. Also, nanotechnology is a potential candidate to offer another solution to improve oil recovery. Nanoparticles can form a solid layer at the droplet's interface and stand as resistant stabilizer under harsh reservoir conditions.

This research investigates whether the combination of surfactants and nanoparticles can provide a more stable emulsion than surfactants only. Two parts of experimental study have been done in …

Online Diagnosis Of Diabetes With Twitter Data, Farheen Ali

Masters Theses

"Innovation in technology enables people to communicate, share information and look for their needs by just sitting in rooms and going through some clicks. While social media has played a very important role in connecting people worldwide, its potential has stretched beyond the innovative idea of connecting people through their social networks. While many thought there was no meeting point for the healthcare sector and social media, it was a surprise when research and innovations have shown that social media could lay a very significant role in the health care sector.

Research has been done in developing models that could …

Determining Rockfall Volumes In Three Sites Along Habs Mountain Road In Southwestern Saudi Arabia, Using Lidar Technology, Abdullah Ayed Al-Otaibi

Masters Theses

"The rugged elevated topography is a characteristic feature of the western and southwestern regions of Saudi Arabia. Few arterial roads connect the scattered villages of these regions to major cities, such as Habs Road in Jazan region. Rock fall poses a serious hazard to people, property and animals along the rock cuts of this road. Although no traditional Rockfall studies have previously been applied to this road, accessibility and rock formation shape and structure variability influenced the choice of using Terrestrial Light Detection And Ranging (LiDAR) technology to calculate the volume of rockfall at selected sites along this road.

Software …

Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik

Masters Theses

"In detonative combustion very high temperatures are attained by the burned gases. As a result, a large amount of thermal energy is produced during the combustion process. This heat can affect the state of the unburned fuel through radiation of heat from the burned gases. In this study a one-dimensional model was deemed appropriate to gain insight into the fundamental structure of the detonation wave. In this model, the detonation wave divides the fluid stream into an upstream region, consisting of fuel and oxidant, and a downstream region, consisting of burned gases. A set of computer programs, some developed during …

Palynological Interpretations Of Deep Sea Drilling Projects Cores In The Gulf Of Mexico And Bahamian Platform, Adam Patrick Barron

Masters Theses

"One hundred drill core samples were from Deep Sea Drilling Project (DSDP) Sites 94, 98, and 540 were investigated for their palynological contents (pollen, spores, acritarchs, dinoflagellate cysts, and dispersed organic matter) to infer the paleoenvironmental and paleoceanographic history of the Gulf of Mexico and the Bahamian Platform during the middle Eocene to middle Miocene interval. At Sites 94 and 540, abundant dinoflagellate cysts (chiefly Operculodinium centrocarpum, Lingulodinium machaerophorum, Impagidinium sp., Nematosphaeropsis sp., and Spiniferites spp.) were used as paleoenvironmental indicators. Two alternating palynofacies assemblages were identified from dispersed organic matter analysis: terrestrially influenced assemblage A and marine dominated assemblage …

Impact Of Configuration Variations On Small Modular Reactor Core Performance, William Kirby Compton

Masters Theses

"One of the most promising new reactor designs is the Small Modular Reactor (SMR). These reactors, which operate under 300 MWe, will help bring cheap and safe nuclear energy to remote and centralized locations alike. Their ease of construction, advanced passive safety features, and cost effectiveness make these reactors an intriguing option for the near future.

In the work presented here, a neutronics analysis of the Westinghouse SMR was performed. Westinghouse's SMR design is a scaled down version of their AP1000 plant and will produce about 225 MWe of power. Though the parameters of the reactor core will be modeled …

Computer Aided Detection Of Oral Lesions On Ct Images, Shaikat Mahmood Galib

Masters Theses

"Oral lesions are important findings on computed tomography images. They are difficult to detect on CT images because of low contrast, arbitrary orientation of objects, complicated topology and lack of clear lines indicating lesions. In this thesis, a fully automatic method to detect oral lesions from dental CT images is proposed to identify (1) Closed boundary lesions and (2) Bone deformation lesions. Two algorithms were developed to recognize these two types of lesions, which cover most of the lesion types that can be found on CT images. The results were validated using a dataset of 52 patients. Using non training …

Comprehensive Benefits Of Green Roofs, Madison R. Gibler

Masters Theses

"Green infrastructure uses vegetation, soils, and natural processes to manage water and create healthier urban environments, providing traditional roof services and alternative stormwater management technologies. Other benefits and impacts are not yet fully understood or valued. Research conducted assesses specific stormwater benefits of green roofs, providing information on nutrient leaching from media; and analyzes potential energy benefits through side-by-side comparisons of full-scale white, traditional black rubber, and green roofs in the mid-continent Missouri climate. Roofing media selection impacted leaching of nutrients, suspended solids, and organic carbon from the tested green roof media. Thermal properties were investigated at the building level, …

Pipeline Leak Detection, Marcia Golmohamadi

Masters Theses

"In the present research two techniques are applied for leak detection in pipelines. The first method is a hardware-based technique which uses ultrasonic wave's emission for pipeline inspection. Ultrasonic waves are propagated in the pipe walls and reflected signal from leakage will be used for pipe analysis. Several Pipes with various dimensions and characteristics are modeled by finite element method using ANSYS. Second order longitudinal modes of ultrasonic waves are emitted in their walls. For this purpose, excited frequency is calculated such that it excites the second order longitude mode. In order to investigate the behavior of emitted wave in …

Model Predictive Current Control Of Switched Reluctance Motor With Inductance Auto-Calibration, Xin Li

Masters Theses

"The thesis is composed of three papers, which investigate the application of Model Predictive Controller (MPC) for current control of Switched Reluctance Motor (SRM). Since the conventional hysteresis current control method is not suitable for high power SRM drive system with low inductance and limited switching frequency, MPC is a promising alternative approach for this application. The proposed MPC can cope with the measurement noise as well as uncertainties within the machine inductance profile. In the first paper, a MPC current control method for Double-Stator Switched Reluctance Motor (DSSRM) drives is presented. A direct adaptive estimator is incorporated to follow …

Spatial And Temporal Modulation Of Heat Source Using Light Modulator For Advanced Thermography, Arvindvivek Ravichandran

Masters Theses

"Thermography is a Non-Destructive Testing (NDT) method that has found increasing use in industry and research. It has the advantages of being non-contact and be able to interrogate a large surface simultaneously. Active thermography using flash lamps as heat source has been demonstrated for identifying blind holes and delamination in composites. Despite these advancements, active thermographic approach fails to defects like cracks. Under uniform illumination heat flow is predominantly 1D and can easily circumvent a narrow feature. This can be overcome by using a focused light/laser source onto the surface to impose a 3D heat flux. The disadvantage is that …

A New Technique For Modeling The Geomorphology Of A Slow Moving, Soft-Slope Landslide Using Terrestrial Lidar, Nathan Bradley Rohrbaugh

Masters Theses

"Soft slope movement is a big problem whether it involves an engineered slope, one that is near infrastructure, or both. Active landslides that fail slowly sometimes allow ample time to affect remedial works. In order to plan effective remedial works, there needs to be a model of the entire geometry of the slide. This thesis describes a new approach to evaluate the morphology of slope geometry using Light Detection and Ranging (LiDAR) data obtained from simple targets strategically positioned on a slide body. The data was gathered in three-month intervals over a period of one year to allow enough time …

Energy Disaggregation In Nialm Using Hidden Markov Models, Anusha Sankara

Masters Theses

"This work presents an appliance disaggregation technique to handle the fundamental goal of the Non-Intrusive Appliance Load Monitoring (NIALM) problem i.e., a simple breakdown of an appliance level energy consumption of a house. It also presents the modeling of individual appliances as load models using hidden Markov models and combined appliances as a single load model using factorial hidden Markov models. Granularity of the power readings of the disaggregated appliances matches with that of the readings collected at the service entrance. Accuracy of the proposed algorithm is evaluated using publicly released Tracebase data sets and UK-DALE data sets at various …

Fuzzy Adaptive Resonance Theory: Applications And Extensions, Clayton Parker Smith

Masters Theses

"Adaptive Resonance Theory, ART, is a powerful clustering tool for learning arbitrary patterns in a self-organizing manner. In this research, two papers are presented that examine the extensibility and applications of ART. The first paper examines a means to boost ART performance by assigning each cluster a vigilance value, instead of a single value for the whole ART module. A Particle Swarm Optimization technique is used to search for desirable vigilance values. In the second paper, it is shown how ART, and clustering in general, can be a useful tool in preprocessing time series data. Clustering quantization attempts to meaningfully …

3d Numerical Modelling Of Micropiles Interaction With Soil & Rock, Audai Kamal Theinat

Masters Theses

"A 5-span bridge along the Foothills Parkway of the Great Smoky Mountains, TN, was recently completed. Two out of the four piers were instrumented to measure the load transfer in the foundations. The foundations consisted of twenty 10-inch micropiles under the pile cap for each pier. Strain gages were installed and monitored at the different stages of construction. The objective of this research is to examine the interaction between the ground and micropiles using the field data performance and numerical modelling. The 3D computer model consists of the micropile foundation within the steep rock bedding planes and overburden soils. The …

Rote-Lcs Learning Classifier System For Classification And Prediction, Benjamin Daniels

Masters Theses

"Machine Learning (ML) involves the use of computer algorithms to solve for approximate solutions to problems with large, complex search spaces. Such problems have no known solution method, and search spaces too large to allow brute force search to be feasible. Evolutionary algorithms (EA) are a subset of machine learning algorithms which simulate fundamental concepts of evolution. EAs do not guarantee a perfect solution, but rather facilitate convergence to a solution of which the accuracy depends on a given EA's learning architecture and the dynamics of the problem.

Learning classifier systems (LCS) are algorithms comprising a subset of EAs. The …

A Novel Entropy Production Based Full-Chip Tsv Fatigue Analysis, Tianchen Wang

Masters Theses

"Through-silicon vias (TSVs) are subject to thermal fatigue due to stress over time, no matter how small the stress is. Existing works on TSV fatigue all rely on measurement-based parameters to estimate the lifetime, and cannot consider detailed thermal profiles. In this paper, we propose a new method for TSV fatigue prediction using entropy production during thermal cycles. By combining thermodynamics and mechanics laws, the fatigue process can be quantitatively evaluated with detailed thermal profiles. Experimental results show that interestingly, the landing pad possesses the most easy-to-fail region, which generates up to 50% more entropy compared with the TSV body. …

Optimal Techno-Economic Sizing Of Wind/Solar/Battery Hybrid Microgrid System Using The Forever Power Method, Sami Hamed Alalwani

Masters Theses

"Advancement in power electronics, energy storage, control, and renewable energy sources has led to the use of integrated renewable energy sources in islanded microgrids (MG). Also, the uses of integrated renewable energy sources have become more technically applicable, more economically feasible, and more environmentally friendly than conventional sources. As a result, electrification of rural villages using renewable energy technologies has started to become widely adopted around the world. Since generating power from renewable energy sources is highly intermittent and difficult to predict, the use of proper energy storage technology is important to eliminate mismatches between the load demand and generation. …

A Valuation Model For Two-Stage Contract Negotiations Over Multiple Interdependent Issues, Nnaemeka U. Amaeshi

Masters Theses

"Most real-world negotiation scenarios involve multiple interdependent issues over which the negotiating parties will seek an agreement. Simultaneous negotiation over multiple interdependent issues is an especially challenging problem because utility functions of negotiating agents are typically nonlinear and difficult to analyze. Also, negotiations often happen under circumstances of incomplete information, where either party has either little or inaccurate information about the preferences or utilities of the other party. Consequently, negotiations may go over multiple rounds until a mutually acceptable agreement is reached. The objective of this research is to create a quantitative model of decision-making that helps one negotiating party …

Cappack Devices For Enhanced Qnmr Measurements In 1H Nmr Spectroscopy, Lingyu Chi

Masters Theses

"Quantitative NMR analyses can be improved by adding well-defined external references for measuring sample properties on absolute scales. Special Capillary-tube Package (CapPack) devices were invented that provide in situ information (e.g., temperature, pH, pressure, integration, chemical shift, lock, etc.) about a sample with spectral imprimaturs. A new microscale glass-sealing technique produced CapPack devices that can survive high temperatures and pressures in harsh environments. Two CapPack devices are discussed: (1) Gradient CapPack-- a device for examining the irradiation bandwidth of solvent-suppression pulse sequences; (2) T₁ CapPack - a device for examining the T₁ robustness of solvent-suppression pulse sequences. A …

Thermodynamic And Chemical Kinetic Coupled Modeling For The Determination Of Cyclic Combustion Phasing In Hcci Engines, Krishawn Michele Goodwin

Masters Theses

"Homogeneous charge compression ignition (HCCI) is a low temperature combustion mode that contains great potential for decreasing emissions while increasing efficiency in internal combustion engines. The limitation is in that it is inherently difficult to control based on the lack of an external combustion trigger. This thesis outlines the potential of using the combustion residual species of carbon monoxide as a method of controlling the location of combustion by using data from a computer model. The model is a nonlinear five-state thermodynamic model that is coupled with a skeletal chemical kinetic model for PRF96. The model computes the amount of …

Design And Implementation Of Low Complexity Wake-Up Receiver For Underwater Acoustic Sensor Networks, Ming Yue

Masters Theses

"This thesis designs a low-complexity dual Pseudorandom Noise (PN) scheme for identity (ID) detection and coarse frame synchronization. The two PN sequences for a node are identical and are separated by a specified length of gap which serves as the ID of different sensor nodes. The dual PN sequences are short in length but are capable of combating severe underwater acoustic (UWA) multipath fading channels that exhibit time varying impulse responses up to 100 taps. The receiver ID detection is implemented on a microcontroller MSP430F5529 by calculating the correlation between the two segments of the PN sequence with the specified …

Fault Interpretation And Reservoir Characterization Of The Farewell Formation Within Kerry Field, Taranaki Basin, New Zealand, Waleed Deefallah M Alotaby

Masters Theses

"The Kerry Field, located in the southern offshore Taranaki Basin, is a large liquid-rich gas accumulation with a thin (20 m) oil rim. The field was discovered by the New Zealand Oil & Gas in 1986 (well Kupe South-1). The gas and oil are trapped within a 9.2 km² fault-dependent three-way dip closure in the Paleocene Farewell Formation reservoir. Pressure, volume, and temperature (PVT) data indicate that the gas and oil columns in the field are in equilibrium with one another and are saturated at current reservoir conditions.

The Farewell Formation is the uppermost formation of the Kapuni Group …