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Engineering Of Hole Transport And Perovskite Absorber Layers To Achieve High Efficiency And Stable Perovskite Solar Cells, Sally Mabrouk Jan 2018

Engineering Of Hole Transport And Perovskite Absorber Layers To Achieve High Efficiency And Stable Perovskite Solar Cells, Sally Mabrouk

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) offer tremendous potential for simple and low-cost solution-based fabrication with high power conversion efficiency, making it a promising renewable energy source alternative to the most common non-renewable energy sources as fossil fuels. The most widely used perovskite for solar cell applications is methylammonium lead triiodide (CH3NH3PbI3). The two structures for PSC are the regular nip device typically fabricated using Spiro- OMeTAD as a hole transport material (HTM), and the inverted pin device fabricated using PEDOT:PSS as a HTM. They have achieved over 20% power conversion efficiency. However, devices are not reproducible or stable and HTMs are …


Development Of Texture Weighted Fuzzy C-Means Algorithm For 3d Brain Mri Segmentation, Ji Young Lee Jan 2018

Development Of Texture Weighted Fuzzy C-Means Algorithm For 3d Brain Mri Segmentation, Ji Young Lee

Electronic Theses and Dissertations

The segmentation of human brain Magnetic Resonance Image is an essential component in the computer-aided medical image processing research. Brain is one of the fields that are attracted to Magnetic Resonance Image segmentation because of its importance to human. Many algorithms have been developed over decades for brain Magnetic Resonance Image segmentation for diagnosing diseases, such as tumors, Alzheimer, and Schizophrenia. Fuzzy C-Means algorithm is one of the practical algorithms for brain Magnetic Resonance Image segmentation. However, Intensity Non- Uniformity problem in brain Magnetic Resonance Image is still challenging to existing Fuzzy C-Means algorithm. In this paper, we propose the …


Development Of Vegetation Mapping With Deep Convolutional Neural Network, Sae-Han Suh Jan 2018

Development Of Vegetation Mapping With Deep Convolutional Neural Network, Sae-Han Suh

Electronic Theses and Dissertations

The Precision Agriculture plays a crucial part in the agricultural industry about improving the decision-making process. It aims to optimally allocate the resources to maintain the sustainable productivity of farmland and reduce the use of chemical compounds. [17] However, the on-site inspection of vegetations often falls to researchers’ trained eye and experience, when it deals with the identification of the non-crop vegetations. Deep Convolution Neural Network (CNN) can be deployed to mitigate the cost of manual classification. Although CNN outperforms the other traditional classifiers, such as Support Vector Machine, it is still in question whether CNN can be deployable in …


Optimization Of Microfluidic Particle Separator Geometry Using Computational Fluid Dynamics, Joseph Petersen Jan 2018

Optimization Of Microfluidic Particle Separator Geometry Using Computational Fluid Dynamics, Joseph Petersen

Electronic Theses and Dissertations

Computational fluid dynamics software was used to simulate the motion of circulating tumor cells in a variety of microfluidic cell isolation devices. Design of several novel microfluidic cell isolation devices was aided by viewing streamlines of fluid in devices in simulation. Devices that performed best in simulation used 5-micrometer wide guiding channels to guide cells to the capture location in the device. While these devices performed better than other devices in simulation and captured all particles regardless of position along inlet, experimental results differ from simulation.


Electro-Magnetic Responsive Ni0.5zn0.5fe2o4 Nano-Particle Composite, Jaiprakash Kanagaraj Jan 2018

Electro-Magnetic Responsive Ni0.5zn0.5fe2o4 Nano-Particle Composite, Jaiprakash Kanagaraj

Electronic Theses and Dissertations

The purpose of this study is to simulate and synthesize a Radar (or Radiation) Absorbent Material (RAM) by using polymers and nickel zinc ferrite (Ni0.5Zn0.5Fe2O4) magnetic nanoparticles. There is an ardent desire in military, space and electronics for lighter, faster, cheaper and widespread bandwidth providing RAM materials. Electromagnetic property such as magnetic permeability and electric permittivity play a major in controlling the radiation. The appropriate combination of permeability and permittivity properties is acquired for the synthesis of RAM providing wide-ranging bandwidth. The apt property is achieved by rule of mixture, mixing of particular composition of epoxy polymer having low permeability …


An Approach To Finding Parking Space Using The Csi-Based Wifi Technology, Yunfan Zhang Jan 2018

An Approach To Finding Parking Space Using The Csi-Based Wifi Technology, Yunfan Zhang

Electronic Theses and Dissertations

With ever-increasing number of vehicles and shortages of parking spaces, parking has always been a very important issue in transportation. It is necessary to use advanced intelligent technologies to help drivers find parking spaces, quickly. In this thesis, an approach to finding empty spaces in parking lots using the CSI-based WiFi technology is presented. First, the channel state information (CSI) of received WiFi signals is analyzed. The features of CSI data that are strongly correlated with the number of empty slots in parking lots are identified and extracted. A machine learning technique to perform multi-class classification that categorizes the input …


Volumetric Three-Component Velocimetry Two-Phase Flow Measurements Of Sediment Suspension Under Regular Plunging Waves, Deryn Ann Beck Jan 2018

Volumetric Three-Component Velocimetry Two-Phase Flow Measurements Of Sediment Suspension Under Regular Plunging Waves, Deryn Ann Beck

Electronic Theses and Dissertations

Breaking waves suspend and transport large amounts of sediment particles in the surf zone. Two important aspects of the problem are the mechanism of sediment suspension and the distribution of the suspended sediment. One approach to solving this problem is to measure the sediment particles’ position and movement simultaneously with the characteristics of the flow field. Previous studies have found that sediment suspension events are related to a number of flow parameters including the vertical velocity, vorticity, horizontal velocity, turbulent kinetic energy, total shear stress, and turbulent shear stress. The objective of this study was to design and conduct an …


Simulation Of Gas Dynamic Cold Spray Process, Sai Rajkumar Vadla Jan 2018

Simulation Of Gas Dynamic Cold Spray Process, Sai Rajkumar Vadla

Electronic Theses and Dissertations

The utilization of computational fluid dynamics (CFD) as a study tool in the aerodynamics and turbomachinery industry reinforces efficiency in the design of aircraft or for understanding the flow through pipes. CFD offer tools to model different geometries and perform a more extensive study of the flow phenomena. This gives the opportunity to model a variety of geometries and analyze their behavior under different operating conditions. A similar approach can be applied to coating technologies. Coating technologies play an essential role in the manufacturing industry. Their ability to form layers of specific materials onto engineering components to enhance mechanical and …


Development Of Polylactic Acid (Pla)-Based Nanocomposite Films For Smart Food Packaging Applications, Zeyad Albahr Jan 2018

Development Of Polylactic Acid (Pla)-Based Nanocomposite Films For Smart Food Packaging Applications, Zeyad Albahr

Electronic Theses and Dissertations

Most of current food packaging resources are non-renewable and nonbiodegradable. The use of these materials has resulted in serious environmental issues. In recent years, the recognition of waste disposal problems and their impacts on the environment has risen the demand for packaging manufactured from renewable materials. However, there are some limitations of using biopolymers for food packaging applications. These limitations include unreliable mechanical and barrier properties. These issues may be addressed by combining biopolymers and nanotechnologies. Nanotechnologies are expected to improve the performance of biopolymer-based packaging materials for food packaging applications. Cellulose nanocrystals (CNC) has shown a potential to be …


Design, Implementation And A Pilot Study Of Mobile Framework For Pedestrian Safety Using Smartphone Sensors, Aawesh Man Shrestha Jan 2018

Design, Implementation And A Pilot Study Of Mobile Framework For Pedestrian Safety Using Smartphone Sensors, Aawesh Man Shrestha

Electronic Theses and Dissertations

Pedestrian distraction from smartphones is a serious social problem that caused an ever increasing number of fatalities especially as virtual reality (VR) games have gained popularity recently. In this thesis, we present the design, implementation, and a pilot study of WiPedCross, a WiFi direct-based pedestrian safety system that senses and evaluates a risk, and alerts accordingly the user to prevent traffic accidents. In order to develop a non-intrusive, accurate, and energy-efficient pedestrian safety system, a number of technical challenges are addressed: to enhance the positioning accuracy of the user for precise risk assessment, a map-matching algorithm based on a Hidden …


Additive Manufacturing With High Density Polyethylene: Mechanical Properties Evaluation, Calvin Wampol Jan 2018

Additive Manufacturing With High Density Polyethylene: Mechanical Properties Evaluation, Calvin Wampol

Electronic Theses and Dissertations

High-density polyethylene is a common recyclable plastic that has a large potential as an additive manufacturing material due its economic and environmental benefits. However, high-density polyethylene has undesirable thermal properties that cause the material to shirk and not adhere to the printing bed during an additive manufacturing processes. Researchers have attempted to combat these thermal properties but have only created novel filaments of high-density polyethylene without being able to create 3D printed specimens for mechanical property testing. This paper presents several methods to create 3D printed specimens with pure high-density polyethylene filament on a fused filament fabrication type 3D printer. …


Nonlinear Stochastic Filtering For Online State Of Charge And Remaining Useful Life Estimation Of Lithium-Ion Battery, Suresh Daravath Jan 2018

Nonlinear Stochastic Filtering For Online State Of Charge And Remaining Useful Life Estimation Of Lithium-Ion Battery, Suresh Daravath

Electronic Theses and Dissertations

Battery state monitoring is one of the key techniques in Battery Management System (BMS). Accurate estimation can help to improve the system performance and to prolong the battery lifetime. The main challenges for the state online estimation of Li-ion batteries are the flat characteristic of open circuit voltage (OCV) with the function of the state of charge. Hence, the focus of this thesis study is to estimation of the state of charge (SOC) of Li-ion with high accuracy, more robustness. A 2nd order RC equivalent circuit model is adapted to battery model for simulation, mathematical model analysis, and dynamics characteristic …


Measuring The Influence Of Bedding On Soil Nitrogen Losses And Corn Crop Nitrogen Characteristics For Fall Applied Solid Beef Cattle Manure In Eastern South Dakota, Mukesh Mehata Jan 2018

Measuring The Influence Of Bedding On Soil Nitrogen Losses And Corn Crop Nitrogen Characteristics For Fall Applied Solid Beef Cattle Manure In Eastern South Dakota, Mukesh Mehata

Electronic Theses and Dissertations

Nitrogen (N) is a major component of chlorophyll which plays a key role in the photosynthesis process in crops. The N is one of the highest demanded nutrients by all plants for their growth and reproduction. Manure or inorganic fertilizer is often applied to fulfill the crops’ N demand. However, the applied N sources have the potential of N losses in different forms from the soil volume in many ways such as ammonia (NH3) volatilization, aerial nitrous oxide (N2O) loss, nitrate (NO3 --N) leaching, and runoff and/or erosion. Soil fertility, crop yield, water quality, and …


Service Integration Design Patterns In Microservices, Meng Wang Jan 2018

Service Integration Design Patterns In Microservices, Meng Wang

Electronic Theses and Dissertations

“Microservices” is a new term in software architecture that was defined in 2014 [1]. It is a method to build a software application with a set of small services. Each service has its process to serve a single purpose and communicates with other services through lightweight mechanisms. Because of a great deal of independently distributed services, it is a challenge to integrate the loose services fully. Too many trivial relationships can be messed up easily during deployment. Also, it is hard to modify the relationships if the services are updated as the source codes need to be re-edited and tested. …


Localization Of Microcalcification On The Mammogram Using Deep Convolutional Neural Network, Jieun Jhang Jan 2018

Localization Of Microcalcification On The Mammogram Using Deep Convolutional Neural Network, Jieun Jhang

Electronic Theses and Dissertations

Breast cancer is the most common cancer in women worldwide, and the mammogram is the most widely used screening technique for breast cancer. To make a diagnosis in the early stage of breast cancer, the appearance of masses and microcalcifications on the mammogram are two crucial indicators. Notably, the early detection of malignant microcalcifications can facilitate the diagnosis and the treatment of breast cancer at the appropriate time. Making an accurate evaluation on microcalcifications is a timeconsuming and challenging task for the radiologists due to the small size and the low contrast of microcalcification. Compared to the background and mammogram …


Location Optimization Of A Coal Power Plant To Balance Coal Supply And Electric Transmission Costs Against Plant’S Emission Exposure, Najam Khan Jan 2018

Location Optimization Of A Coal Power Plant To Balance Coal Supply And Electric Transmission Costs Against Plant’S Emission Exposure, Najam Khan

Electronic Theses and Dissertations

This research is focused on developing a location analysis methodology that can minimize the pollutant exposure to the public while ensuring that the combined costs of electric transmission losses and coal logistics are minimized. Coal power plants will provide a critical contribution towards meeting electricity demands for various nations in the foreseeable future. The site selection for a new coal power plant is extremely important from an investment point of view. The operational costs for running a coal power plant can be minimized by a combined emphasis on placing a coal power plant near coal mines as well as customers. …


Lcd 3d Printing Of A Photocurable Elastomer For Tissue Engineering, Beatriz Luiza De Souza Jan 2018

Lcd 3d Printing Of A Photocurable Elastomer For Tissue Engineering, Beatriz Luiza De Souza

Electronic Theses and Dissertations

Three-dimensional scaffolding is an emerging research area in biomedical and tissue engineering. Scaffolds provide the possibility of growing tissues in a controlled environment, with desired characteristics and properties towards a specific application. A new method to 3D print biodegradable and biocompatible material called Polyglycerol Sebacate Acrylate (PGSA) is demonstrated. PGSA is essentially an acrylated form of PGS using photoinitiator to become a photocurable resin suitable for liquid crystal display (LCD) 3D printing. PGSA was selected because its rheological and crosslinking behavior (and hence its mechanical properties) can be controlled by changes in curing time, temperature, and pressure. This material has …


Mechanical Bar Splices For Accelerated Construction Of Bridge Columns, Puskar Kumar Dahal Jan 2018

Mechanical Bar Splices For Accelerated Construction Of Bridge Columns, Puskar Kumar Dahal

Electronic Theses and Dissertations

Mechanical bar splicing is an alternative method of connecting reinforcing bars in concrete structures compared to conventional lap splicing mainly to reduce bar congestion in joints. Recently, mechanical bar splices, which are also referred to as bar couplers, have been used to connect precast members to accelerate construction of concrete bridges and buildings. Current codes prohibit the use of couplers in the plastic hinge regions of bridge columns in high seismic zones. This may be because of a lack of systematic test data on the coupler performance, limited experimental studies on mechanically spliced bridge columns, and an engineering precaution. The …


Enabling Low Cost Wifi-Based Traffic Monitoring System Using Deep Learning, Sayan Sahu Jan 2018

Enabling Low Cost Wifi-Based Traffic Monitoring System Using Deep Learning, Sayan Sahu

Electronic Theses and Dissertations

A traffic monitoring system (TMS) is an integral part of Intelligent Transportation Systems (ITS) for traffic analysis and planning. However, covering huge miles of rural highways (119,247 miles in U.S.) with a large number of TMSs is a very challenging problem due to the cost issue. This paper aims to address the problem by developing a low-cost and portable TMS called DeepWiTraffic based on COTs WiFi devices. The proposed system enables accurate vehicle detection (counting) and classification by exploiting the unique WiFi Channel State Information (CSI) of passing vehicles. Spatial and temporal correlations of CSI amplitude and phase data are …


Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya Jan 2018

Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya

Electronic Theses and Dissertations

The availability of water resources varies from time to time with the climate conditions. Keeping track of climate conditions would eventually benefit for the future predictions. The objective of this research was to compare and contrast the climate especially for Aberdeen, Ipswich and Eureka, South Dakota utilizing the historical monthly precipitation records and to develop the techniques that are reliable to estimate the missing data. For these necessary statistical analyses were performed using the monthly precipitation data from High Plains Regional Climate Center (HPRCC) for the annual and 8-Year periods for Aberdeen, Ipswich and Eureka, South Dakota. 63 water years …


Optimization Of Heat Sinks In A Range Of Configurations., Archibald Allswell Amoako Jan 2018

Optimization Of Heat Sinks In A Range Of Configurations., Archibald Allswell Amoako

Electronic Theses and Dissertations

In this study, different heatsink geometries used for electronic cooling are studied and compared to each other to determine the most efficient. The goal is to optimize heat transfer of the heat sinks studied in a range of configuration based on fin geometry. Heat sinks are thermal conductive material devices designed to absorb and disperse heat from high-temperature objects (e.g. Computer CPU). Common materials used in the manufacturing of heat sinks are aluminum and copper due to their relatively high thermal conductivity and lightweight [1]. Aluminum is used as the material for the heatsinks studied in this research project. To …


Study Of Seasonal Change And Water Stress Condition In Plant Leaf Using Polarimetric Lidar Measurement, Prabeen Kattel Jan 2018

Study Of Seasonal Change And Water Stress Condition In Plant Leaf Using Polarimetric Lidar Measurement, Prabeen Kattel

Electronic Theses and Dissertations

Study of vegetation is of great importance to the improvement of agriculture and forest management. Although there have been various attempts to characterize vegetation using remote sensing techniques, polarimetric lidar is a novel remote sensing tool that has shown potential in vegetation remote sensing. In this thesis, a near-infrared polarimetric lidar at 1064 nm was used to investigate the effects of seasonal change and water stress condition on plant leaves. Two variables, time and water content, affected the plant leaf laser depolarization ratio measurement. The first study focused on the maple tree in order to figure out how seasonal change …


Wi-Fi Finger-Printing Based Indoor Localization Using Nano-Scale Unmanned Aerial Vehicles, Appala Narasimha Raju Chekuri Jan 2018

Wi-Fi Finger-Printing Based Indoor Localization Using Nano-Scale Unmanned Aerial Vehicles, Appala Narasimha Raju Chekuri

Electronic Theses and Dissertations

Explosive growth in the number of mobile devices like smartphones, tablets, and smartwatches has escalated the demand for localization-based services, spurring development of numerous indoor localization techniques. Especially, widespread deployment of wireless LANs prompted ever increasing interests in WiFi-based indoor localization mechanisms. However, a critical shortcoming of such localization schemes is the intensive time and labor requirements for collecting and building the WiFi fingerprinting database, especially when the system needs to cover a large space. In this thesis, we propose to automate the WiFi fingerprint survey process using a group of nano-scale unmanned aerial vehicles (NAVs). The proposed system significantly …


Low Power Wide Area Networks (Lpwan): Technology Review And Experimental Study On Mobility Effect, Dhaval Patel Jan 2018

Low Power Wide Area Networks (Lpwan): Technology Review And Experimental Study On Mobility Effect, Dhaval Patel

Electronic Theses and Dissertations

In the past decade, we have witnessed explosive growth in the number of low-power embedded and Internet-connected devices, reinforcing the new paradigm, Internet of Things (IoT). IoT devices like smartphones, home security systems, smart electric meters, garage parking indicators, etc., have penetrated deeply into our daily lives. These IoT devices are increasingly attached and operated in mobile objects like unmanned vehicles, trains, airplanes, etc. The low power wide area network (LPWAN), due to its long-range, low-power and low-cost communication capability, is actively considered by academia and industry as the future wireless communication standard for IoT. However, despite the increasing popularity …


Effect Of Poisson’S Ratio On Young's Modulus Characterization Using Ultrasonic Technique By Modeling, Michael Onyetube Jan 2018

Effect Of Poisson’S Ratio On Young's Modulus Characterization Using Ultrasonic Technique By Modeling, Michael Onyetube

Electronic Theses and Dissertations

The past 27 years has witnessed a revolutionary growth in the progress of material development and application in almost all industry and business sectors, and this seems to be continuing even today. So many material-driven innovations have enabled the global spread in technology and improvements in capability, ranging from communications to aerospace and healthcare, to automotive and agriculture. Mechanical behavior of elastic materials is modeled by two main independent constants; Young’s modulus and Poisson’s ratio. An accurate measurement of both constants is necessary in most engineering applications, for example, the standard materials used for the calibration of some equipment, quality …


Development Of Material For 3d Printed Habitats With Extraplanetary Applications, Taylor Wait Jan 2018

Development Of Material For 3d Printed Habitats With Extraplanetary Applications, Taylor Wait

Electronic Theses and Dissertations

3D printing, also called Additive Manufacturing, has increasingly become a focus for research because of the potential to replace complicated assemblies or complex parts with a single printed item. The space industry is very interesting in studying 3d printing with parts being tested and used on rockets, a 3D printer being installed at the International Space Station and is being developed for use in manned exploration of extraplanetary bodies to build habitats. To encourage teams from around the world to develop technologies and materials for autonomous habitat construction using minimal Earth exports, NASA created the 3D Printed Habitat Challenge. NASA …


Techno-Economic Analysis Of Pv Inverter Based Controllers On Low Voltage Distribution Networks, Rupak Mahat Jan 2018

Techno-Economic Analysis Of Pv Inverter Based Controllers On Low Voltage Distribution Networks, Rupak Mahat

Electronic Theses and Dissertations

Voltage-rise due to increasing installation of photovoltaic (PV) systems is a major technical issue in low voltage distribution networks. A cost-effective approach to address the overvoltage problem is to control the active and reactive power provided by the existing PV inverters. Prior research used electro-magnetic transient (EMT) simulation tools to develop inverter control strategies for overvoltage prevention. These type of simulation requires high computational resources and simulation time, and is therefore not suitable for long time period studies (e.g., annual) with many inverters. With the anticipated high penetration of PV, there is a desire for a suitable tool for long …


Simulation Of Different Rib Shapes In Square Channel, Md Sahedul Islam Jan 2018

Simulation Of Different Rib Shapes In Square Channel, Md Sahedul Islam

Electronic Theses and Dissertations

This study investigates heat transfer and pressure drop for rib-roughened square channel without bleed. To optimize the shape of rib, CFD tools were used to model and simulate channel flow with a variety of rib angles and geometries. To validate simulations and determine the turbulence model, experimental results for two-pass channels with ribs at 45˚ angles with BR = 0 and Re = 25,000 was compared. It was found after conducting simulations with different turbulence models that SST turbulence model gave the best results.


Cross Calibration And Validation Of Landsat 8 Oli And Sentinel 2a Msi, M. M. Farhad Jan 2018

Cross Calibration And Validation Of Landsat 8 Oli And Sentinel 2a Msi, M. M. Farhad

Electronic Theses and Dissertations

This work describes a proposed radiometric cross calibration between the Landsat 8 Operational Land Imager (OLI) and Sentinel 2A Multispectral Instrument (MSI) sensors. The cross calibration procedure involves i) correction of the MSI data to account for spectral band differences with the OLI; and ii) correction of BRDF effects in the data from both sensors using a new model accounting for the view zenith/azimuth angles in addition to the solar zenith/view angles. Following application of the spectral and BRDF corrections, standard least-squares linear regression is used to determine the cross calibration gain and offset in each band. Uncertainties related to …


Evaluation Of The Moisture-Induced Damage Potential Of Asphalt Mixes And Asphalt Binder-Aggregate Systems, Rajan Acharya Jan 2018

Evaluation Of The Moisture-Induced Damage Potential Of Asphalt Mixes And Asphalt Binder-Aggregate Systems, Rajan Acharya

Electronic Theses and Dissertations

The current thesis presents the findings of a study conducted on asphalt mixes to evaluate their moisture-induced damage potential through testing of the plant produced asphalt mixes in South Dakota using local aggregates and commonly used asphalt binders. The moisture-induced damage potentials of the asphalt mixes were evaluated by conducting tensile strength ratio (TSR) and modified Semicircular Bend (SCB) tests. The effect of moisture on asphalt binder-aggregate adhesion was evaluated by conducting binder bond strength (BBS) test on binder-aggregate systems. The asphalt mixes tested in this study included a hot mix asphalt (HMA) containing hydrated lime (1% by the weight …