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Csar 62 Spin Curve, Mohsen Azadi, Georgia Griggs, Glen de Villafranca, Gerald Lopez 2018 Singh Center for Nanotechnology

Csar 62 Spin Curve, Mohsen Azadi, Georgia Griggs, Glen De Villafranca, Gerald Lopez

Protocols and Reports

No abstract provided.


Jpk.Pdf, jpk sonick 2018 Eastern Washington University

Jpk.Pdf, Jpk Sonick

jpk sonick

Kami menerima jasa refill tabung pemadam kebakaran untuk berbagai merk yang berada di pasaran dan untuk berbagai media


Icdcs2018_Dumitru_Paper_1243.Pdf, Ion Dumitru 2018 Boral Ltd

Icdcs2018_Dumitru_Paper_1243.Pdf, Ion Dumitru

Ion Dumitru

Remedial work for an iconic building in Sydney, Australia is currently being carried out. Two façade mortars, capable of matching the current exposed quartz aggregate finish and achieving a 40 years design life, are required. In order to ensure the quality of the imported quartz aggregates for this project, test have been carried out for particle size distribution, density, wet/dry strength variation, sodium sulphate soundness and Los Angeles Abrasion value. The two mortar mixes employed for repair work (Form & Pour and Hand Applied mixes) were comprehensively assessed for mix workability, compressive strength in warm and cold conditions, drying shrinkage ...


Systems Engineering Analysis For Optimum Selection Protocol For Thermal Expansion Measurement Of A Carbon Fiber Reinforced Composite Tube, Ronald Uchimiya 2018 Loyola Marymount University

Systems Engineering Analysis For Optimum Selection Protocol For Thermal Expansion Measurement Of A Carbon Fiber Reinforced Composite Tube, Ronald Uchimiya

LMU/LLS Theses and Dissertations

A material’s Coefficient of Thermal Expansion (CTE) is a valuable physical property, particularly for structural fiber reinforced composites that are routinely used in satellite/aerospace applications. Satellite space structures are routinely designed with a high degree of dimensional and thermal stability. Designing and verifying for near zero CTE performance is a common design requirement. The CTE is routinely a physical property with known values for common materials. However, the strength, stiffness and CTE properties on a multi-ply graphite fiber reinforced laminate composite can be tailored to specific engineering requirements. Because of this, a method of verification (testing) is routinely ...


Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall 2018 Utah State University

Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall

All Graduate Theses and Dissertations

A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the ...


Size-Scale Effects Of Nonlinear Weir Hydraulics, Nathan L. Young 2018 Utah State University

Size-Scale Effects Of Nonlinear Weir Hydraulics, Nathan L. Young

All Graduate Theses and Dissertations

Experimental physical model studies of hydraulic structures are often conducted to replicate flow behavior that may occur at the prototype scale. Geometric similitude is most often maintained between the prototype and model when studying reservoir and open channel hydraulic structures to account for the dominant gravity and inertia forces while other fluid forces (e.g., viscosity,surface tension) are assumed negligible. However, as model size and/or upstream head decreases, other fluid forces can exceed the negligible level and influence model flow behavior. This phenomenon is referred to as size-scale effects and is one potential origin of error in predicting ...


Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal 2018 Utah State University

Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal

All Graduate Theses and Dissertations

Deeper understanding of relationships between flow in river sand various hydrologic elements such as rainfall, land use, and soil type is imperative to solve water related problems like droughts and floods. Advanced computer models are becoming essential in helping us understand such relationships. However, preparing such models requires huge investment of time and resources, much of which are concentrated on acquisition and curation of data. This work introduces agree and open source web Application (web App) that provides researchers with simplified access to hydrological data and modeling functionality. The web App helps in the creation of both hydrologic models, and ...


Simulation And Optimization Models To Evaluate Performance Of Aquifer Storage And Recovery Wells In Fresh Water Aquifers, Ali Forghani 2018 Utah State University

Simulation And Optimization Models To Evaluate Performance Of Aquifer Storage And Recovery Wells In Fresh Water Aquifers, Ali Forghani

All Graduate Theses and Dissertations

Aquifer storage and recovery (ASR) involves artificially recharging an aquifer through well(s) using surplus water for later recovery in high-demand months. The operators of the studied ASR system developed the system as a means of receiving additional water rights to supplement their pre-existing water rights for extraction in dry months. However, the region’s water regulators define the performance of this ASR system as the amount of the injected water that is recoverable from the same wells during extraction periods. The study proposes recovery effectiveness (REN) as the performance index of this ASR system. REN equals the injectate proportion ...


Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor 2018 Utah State University

Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor

All Graduate Theses and Dissertations

The design of an aircraft wing often involves the use of mathematical methods for simultaneous aerodynamic and structural design. The goal of many of these methods is to minimize the drag on the wing. A variety of computer models exist for this purpose, but some require the use of expensive time and computational resources to give meaningful results. As an alternative, some mathematical methods have been developed that give reason ably accurate results without the need for a computer. However, most of these methods can only be used for wings with specific shapes and payload distributions. In this thesis, a ...


Evaluating Water Filtration And Disinfection For Household, Using Slow Sand Filters Plus Solar Disinfection, Mariana Demitry 2018 Utah State University

Evaluating Water Filtration And Disinfection For Household, Using Slow Sand Filters Plus Solar Disinfection, Mariana Demitry

All Graduate Theses and Dissertations

In this research, a household water treatment system was built and evaluated as a trial for improving the drinking water quality of the Nile River for the low-income communities. The system consisted of household-scale slow sand filters, and transparent polyethylene terephthalate-bottles for solar disinfection. The evaluation of the system depended on the removal/inactivation of some surrogates for the reference pathogens, and turbidity. The reference pathogens are pathogens specified by the World Health Organization to evaluate the efficiency of the household water treatment options. They were chosen to represent the classes of pathogens in water (bacteria, viruses, protozoa). The surrogates ...


Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens 2018 Utah State University

Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens

All Graduate Theses and Dissertations

Limitations in the quality of transformation rates used with water quality models such as QUAL2K have led to the need to identify methods that can effectively and accurately determine these rates. During the early stages of method development of a Utah Department of Environmental Quality (Utah DEQ) funded project seeking to identify such methods, it was determined that under certain situations external carbon amendment may be required to successfully determine denitrification rates.

The focus of this study was to evaluate the potential impacts that introducing external carbon sources may have on estimating the laboratory denitrification rates resulting from these methods ...


Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris 2018 Utah State University

Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris

All Graduate Theses and Dissertations

Graphene is a form of carbon with unique thermal and structural properties, giving it high potential in many applications, from electronics to driveway heating. Advanced fabrication techniques putting small, graphene-like structures in a polymer matrix could allow for incorporation of some of the benefits of graphene into very lightweight materials, and allow for broader commercialization. Measuring the thermal properties of these thin-film samples is a technical capability in need of development for use with the specific specimens used in this study. Relating those thermal properties to the microstructural composition was the focus of this work.

Several conclusions could be drawn ...


Enhancement Of Dibenzothiophene Hydrodesulphurization Via Hydrogenation Route On Nimow Catalyst Supported On Hms Modified With Ti, Rafael Maya-Yescas 2018 Universidad Michoacana de San Nicolas de Hidalgo

Enhancement Of Dibenzothiophene Hydrodesulphurization Via Hydrogenation Route On Nimow Catalyst Supported On Hms Modified With Ti, Rafael Maya-Yescas

Rafael Maya-Yescas

This study shows that ternary Ni-Mo-W sulfide catalysts supported on hexagonal mesoporous silica modified with Ti (HMS-Ti) showed a high enhancement of dibenzothiophene (DBT) transformation via hydrogenation route with respect to their Ti-free counterpart. The reaction of hydrodesulphurization (HDS) of DBT was carried out at in a batch reactor at 320 °C and 5.5 MPa of total H2 pressure. The catalysts were characterized by a variety of techniques (chemical analysis, N2 adsorption-desorption isotherms, low- and wide-angles XRD, TPR, TPDNH, DRS UV–vis, TPO/TG and HRTEM). At reaction time of 5 h, all synthetized catalysts exhibited higher DBT conversion ...


Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey 2018 Marquette University

Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey

Master's Theses (2009 -)

The objective of this thesis is to design a hybrid sensorless closed-loop motor controller using a combination of Field-Oriented Control (FOC) and Direct Torque Control (DTC) for brushless DC motors used in multi-rotor aerial vehicles. The primary challenge is the wide range of desired working speeds, which can quickly vary from low speed to high speed. For this range, the control approach must be efficient, effective, and low-cost in order to provide fast response times during initial startup, steady-state, and transient operation. Additional design challenges include minimal response time to desired speed changes and small steady-state speed errors. Finally, the ...


On Condition Monitoring Of High Switching Frequency Power Gan Converters With Adaptive Prognostics.Pdf, Mehrdad Biglarbegian 2018 University of North Carolina at Charlotte

On Condition Monitoring Of High Switching Frequency Power Gan Converters With Adaptive Prognostics.Pdf, Mehrdad Biglarbegian

Mehrdad Biglarbegian

There is no doubt that in the future, a need for higher switching frequency is inevitable to extract the full benefits of reliable Gallium Nitride (GaN) device characteristics. Along with the reliability enhancement for GaN-based power converters, it is essential to monitor a precursor signature identification for diagnostics/prognostics techniques. With the availability of the most granular information deduced from advanced devices, a new data-driven scheme is proposed for system monitoring and possible lifetime extension of 400W power GaN converters at 100kHz. The approach relies on the real-time R_ds(on) data extraction from the power converter, and calibration of an ...


Multi-Purpose Generic Board For Hands-On Power Electronics Education Of Different Power Converter Topologies In Pv Applications.Pdf, Mehrdad Biglarbegian 2018 University of North Carolina at Charlotte

Multi-Purpose Generic Board For Hands-On Power Electronics Education Of Different Power Converter Topologies In Pv Applications.Pdf, Mehrdad Biglarbegian

Mehrdad Biglarbegian

This paper presents the development of a multi-purpose generic board for hands-on power electronics education lab session focusing on Photovoltaic (PV) power electronics applications. The presented work tries to apply advanced methods for circuit designs and firmware developments of a DC/DC and a DC/AC converter for helping students to get familiar with system/subsystem level learning. The developed advanced converters can be used for interconnection of low voltage PV systems. Besides, the objective is to expedite the transferring of theory to practical purposes and to provide hands-on experiences for the development of power electronics systems.


Development Of Isolated Sensegan Current Monitoring For Boundary Conduction Mode Control Of Power Converters, Mehrdad Biglarbegian 2018 University of North Carolina at Charlotte

Development Of Isolated Sensegan Current Monitoring For Boundary Conduction Mode Control Of Power Converters, Mehrdad Biglarbegian

Mehrdad Biglarbegian

This paper presents the design of the Isolated SenseGaN (Iso-SenseGaN) current sensing technique using Gallium Nitride (GaN) transistors. The isolation technique for the SenseGaN brings an opportunity for integration of sensing element with the power modules, and enables many control schemes in power converters. This could effectively open broader area for smart device monitoring, implementation of current controlling techniques at high frequency, and proper feedback for diagnostics/prognostics developments. In this work, the focus is on the practical challenges for the SenseGaN technique and presenting the inductor-based galvanic isolation. Using the current mirroring method, the authors defined a cursor for ...


Sample.Docx, bepress support 169, Willie Test 2018 bepress

Sample.Docx, Bepress Support 169, Willie Test

bepress support 169

No abstract provided.


Correlation For Sessile Drop Evaporation Over A Wide Range Of Drop Volatilities, Ambient Gases And Pressures, Peter Kelly-Zion, Christopher J. Pursell, Gregory N. Wassom, Brenton V. Mandelkorn, Chris Nkinthorn 2018 Trinity University

Correlation For Sessile Drop Evaporation Over A Wide Range Of Drop Volatilities, Ambient Gases And Pressures, Peter Kelly-Zion, Christopher J. Pursell, Gregory N. Wassom, Brenton V. Mandelkorn, Chris Nkinthorn

Engineering Faculty Research

A correlation for the evaporation of sessile drops over a very broad range of conditions was developed based on measured evaporation rate data obtained for drops of acetone, methanol, and six hydrocarbons ranging from hexane to isooctane, evaporating in air, helium, argon, and krypton, over a range of ambient pressures from 96 kPa to 615 kPa. The experiments were designed to produce a large variation in the rates of diffusion and buoyancy-induced (natural) convection of the vapor phase amongst the experimental conditions. The correlation, which fits the measurements with an RMS relative error of 5.2%, is a simple equation ...


In Operando Mechanism Analysis On Nanocrystalline Silicon Anode Material For Reversible And Ultrafast Sodium Storage, Lei Zhang, Xianluo Hu, Chaoji Chen, Haipeng Guo, Xiaoxiao Liu, Gengzhao Xu, Haijian Zhong, Shuang Cheng, Peng Wu, Jiashen Meng, Yunhui Huang, Shi Xue Dou, Hua-Kun Liu 2018 University of Wollongong

In Operando Mechanism Analysis On Nanocrystalline Silicon Anode Material For Reversible And Ultrafast Sodium Storage, Lei Zhang, Xianluo Hu, Chaoji Chen, Haipeng Guo, Xiaoxiao Liu, Gengzhao Xu, Haijian Zhong, Shuang Cheng, Peng Wu, Jiashen Meng, Yunhui Huang, Shi Xue Dou, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Presently, lithium-ion batteries (LIBs) are the most promising commercialized electrochemical energy storage systems. Unfortunately, the limited resource of Li results in increasing cost for its scalable application and a general consciousness of the need to find new type of energy storage technologies. Very recently, substantial effort has been invested to sodium-ion batteries (SIBs) due to their effectively unlimited nature of sodium resources. Furthermore, the potential of Li/Li+ is 0.3 V lower than that of Na/Na+, which makes it more effective to limit the electrolyte degradation on the outer surface of the electrode.[1] Nevertheless, one major obstacle ...


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