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Articles 1501 - 1530 of 3180

Full-Text Articles in Engineering

Discriminating Parkinson's Disease Using Functional Connectivity And Brain Network Analysis, Daniel Gellerup May 2016

Discriminating Parkinson's Disease Using Functional Connectivity And Brain Network Analysis, Daniel Gellerup

Industrial, Manufacturing, and Systems Theses - Archive

In this study, we explored the use of functional connectivity patterns in fMRI data to classify subjects on the basis of Parkinson's disease. We explore various brain networks and features. We partition our fMRI data in 5 filtered frequency ranges. We use a proximal support vector machine paired with a minimum-redundancy and maximum-relevance feature selection method on each frequency range. We use a majority voting ensemble classification method on the results of the proximal support vector machine classification results. We use a double 5-fold cross validation scheme for model validation. We achieve 84% accuracy 74% sensitivity, and 93% specificity. Our …


A System Dynamics Approach Applied To Wind Energy System Sustainability, Jenny Maria Tejeda Carlos May 2016

A System Dynamics Approach Applied To Wind Energy System Sustainability, Jenny Maria Tejeda Carlos

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Sustainability of energy systems is one of the most important challenges currently facing humanity. Access to energy is critical to ensure economic and social development of a nation (UNDP et al., 2000); however, extraction, production and consumption of energy resources are also associated with high volumes of greenhouse gas (GHG) emissions, environmental damage and, in some cases, adverse health effects in communities where energy facilities are located. Renewable energy sources have been considered as an alternative to traditional energy sources to meet energy demand in a sustainable manner (Del Rio and Burguillo, 2008). Wind energy is considered to be one …


Dynamic Constraint Optimal Selection Techniques For Linear Programming, Alireza Noroziroshan May 2016

Dynamic Constraint Optimal Selection Techniques For Linear Programming, Alireza Noroziroshan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Linear programming has been studied for over 60 years. It has been considered as one of the most valuable optimization tool for many industrial problems. The simplex algorithm remains the predominant approach to solving linear programming problems. Here we use the simplex method in an active-set frame work to improve it substantially. In general an active-set method obtains solutions by adding one or more problem constraints at a time to solve smaller problems iteratively. In particular, some of these methods have proven to perform significantly faster than the simplex method. In this dissertation we proposed an e?cient constraint selection metric …


Optimization Of Heterogeneous Wireless Networks With Massive Mimo, Shitong Yuan May 2016

Optimization Of Heterogeneous Wireless Networks With Massive Mimo, Shitong Yuan

Electrical Engineering Dissertations - Archive

In the next generation wireless communication system, multi-layers of Heterogeneous Networks (HetNets) are required to provide high efficiency bandwidth usage and high speed data throughput. Users’ distribution and their quality of service (QoS) request are random, and the number of users may vary through the time. In order to deal with this problem, this thesis builds two games’ models to optimize the resource allocation corresponding to different situations in the first chapter. The spectrum efficiency is analyzed and compared between two games. By playing those games, cells can serve more users inside one cell, and all users are fair to …


Hdr Video Compression Using H.265 (Hevc) Main 10 Profile, Srikanth Vasireddy May 2016

Hdr Video Compression Using H.265 (Hevc) Main 10 Profile, Srikanth Vasireddy

Electrical Engineering Theses - Archive

Increasing the resolution of the video has been the main interest in the television industry for a long time. More recently the industry is studying techniques to increase the range of luminance and color representation in videos. This is achieved through High Dynamic Range/ Wide Color Gamut (HDR/WCG) videos by providing visual quality of experience to the end consumers close to that of real life compared to the Standard Dynamic Range (SDR) videos.In order to deliver high-quality video services to consumers, efficient compression techniques are required to store or transmit a video especially for high resolution video formats whilst maintaining …


Improved Similarity Measures For American Sign Language Recognition Using Manual Handshapes And Hand Appearances, Siddhartha Goutham Swaminathan May 2016

Improved Similarity Measures For American Sign Language Recognition Using Manual Handshapes And Hand Appearances, Siddhartha Goutham Swaminathan

Electrical Engineering Theses - Archive

American sign language is a primary language for approximately 0.5 to 2 million people who are deaf or hard of hearing in the United States[22][23]. When a user encounters an English word which he does not understand, he looks up the meaning for it in a dictionary. However, when an American Sign Language (ASL) user encounters an unknown sign, looking up the meaning of that sign is not an easy task. There are many systems available to access ASL signs that require articulatory properties such as handshapes but these systems fail if there is a slight variation of what the …


Multilayer Perceptron With Adaptive Activation Functions, Chinmay Appa Rane May 2016

Multilayer Perceptron With Adaptive Activation Functions, Chinmay Appa Rane

Electrical Engineering Theses - Archive

A Multilayer perceptron typically has a fixed nonlinear activation function for each hidden unit. In this thesis, an adaptive activation function for individual hidden unit is designed, where the network learns these activation functions at every iteration using a modern second order algorithm. Methods and algorithms for these adaptive activation functions along with several other techniques for training a multilayer perceptron’s weights are discussed. Comparisons between a multilayer perceptron with sigmoidal activation functions and a multilayer perceptron with piecewise linear activation functions are also discussed. The common activation function used is the sigmoidal activations, but it is still not proven …


Multi-Stage Enhancement Scheme For Low Quality Fingerprint Images, Ramakrishna Vighna Venkata Lanka May 2016

Multi-Stage Enhancement Scheme For Low Quality Fingerprint Images, Ramakrishna Vighna Venkata Lanka

Electrical Engineering Theses - Archive

Security and authentication go hand in hand in today’s internet age. The population growth and increase in web-based services have posed a substantial risk of identity theft and fraud. The need for reliable authentication to protect one’s belongings has become essential. The goal of such an authentication system is to recognize a person by validating his/her identity. The traditional identity management systems which validate on the basis of knowledge and tokens such as passwords and identity cards are susceptible to theft and duplication. Hence these systems cannot suffice for reliable identity management. Biometrics on the other hand validate an individual …


Reversible Data Hiding Using Histogram Shifting, Sai Saketh Nandagiri May 2016

Reversible Data Hiding Using Histogram Shifting, Sai Saketh Nandagiri

Electrical Engineering Theses - Archive

With the current state-of-the-art technology, intruders can easily gain access to sensitive information. To avoid this, different methods with improved security to hide information have been developed like, covert channels, hiding data in images, null ciphers, etc. The focus of this work is to enhance the security and data hiding capacity of the current state-of-the-art reversible data hiding algorithms. The proposed data hiding method is designed such that the original image is losslessly restored after extraction of a payload. The proposed framework allows embedding of a binary bit stream into the host or cover image while retaining the quality of …


Future Of Jpeg Xt: Privacy And Security, Maitri Shah May 2016

Future Of Jpeg Xt: Privacy And Security, Maitri Shah

Electrical Engineering Theses - Archive

JPEG is de facto the most important and popular image format since 1992 which provides compressed images to a great extent. JPEG XT, the latest standardization of the JPEG committee, provides some amazing features like: backwards compatibility, support for High Dynamic Range (HDR), lossless and near-lossless coding, and alpha channel coding, which were not provided by the previous JPEG standards. With the increase in the demand for photos- capturing, sharing, editing- privacy concerns have become the primary issue. Leakage of private photos to unauthorized users is unacceptable and hence the need for protecting and developing an algorithm to maintain the …


Compression Artifact Reduction In Hevc Using Adaptive Bilateral Filter, Rohith Reddy Etikala May 2016

Compression Artifact Reduction In Hevc Using Adaptive Bilateral Filter, Rohith Reddy Etikala

Electrical Engineering Theses - Archive

The High Efficiency Video Coding (HEVC) [8] is the latest video standard developed by Joint Collaborative Team on Video Coding (JCT-VC), a group of video coding experts from ITU-T Video Coding Experts Group and ISO/IEC Moving Picture Experts Group (MPEG). As the demand for HD video (4K and 8K) increased, there is a need for higher coding efficiency than H.264/AVC. Also, there is increased use of parallel processors. So, HEVC [8] has been introduced to support increased video resolution and parallel processing. HEVC obtains about 50% reduction in bit rate when compared to its predecessor H.264/AVC at the same visual …


A Switched Capacitor Based Transimpedance Amplifier For Detection Of Hab Through Optical Sensing, Uthra Mahendran May 2016

A Switched Capacitor Based Transimpedance Amplifier For Detection Of Hab Through Optical Sensing, Uthra Mahendran

Electrical Engineering Theses - Archive

In the recent years, there has been a substantial increase in the manifestation of harmful algal blooms. A certain species called cyanobacteria that is commonly present in freshwater bodies are found to release a class of deadly toxins known as microcystin. This toxin poses a threat to humans and wildlife since they can cause severe illness or even death on consumption of contaminated water. Traditional sampling methods are essentially lab based detection methods that are inconvenient and demands extensive manual effort. Hence, large-scale occurrence of harmful blooms in water resources demands the development of efficient and reliable methods for monitoring …


Comparison Of Different Metals As Electrodes For A Flexible Micro Ph Sensor, Pavan Kumar Kota May 2016

Comparison Of Different Metals As Electrodes For A Flexible Micro Ph Sensor, Pavan Kumar Kota

Electrical Engineering Theses - Archive

pH can be explained in general terms as a numerical scale used to state the acidity or basicity of an aqueous solution. Keeping track of pH is very useful in many applications like medicine, civil engineering, chemical engineering, biology, water purification etc. Most commonly used pH sensors employ glass electrodes but there are some disadvantages associated with these kinds of pH sensors. Glass is a rigid, chemically reactive and fragile material. Also, glass electrodes, owing to the size require significant quantity of solution to test for pH which makes it difficult to use in cases where we have very little …


Sustainability Assessment Of Recycled Asphalt Mixtures In Texas, Reza Saeedzadeh May 2016

Sustainability Assessment Of Recycled Asphalt Mixtures In Texas, Reza Saeedzadeh

Civil Engineering Dissertations - Archive

The pavement practitioners use more recycled materials in asphalt mixtures in order to compensate for the high price of petroleum products and save the limited resources of virgin materials. Reclaimed Asphalt Pavement (RAP) and Recycled Asphalt Shingles (RAS) have been in wide use in asphalt mixtures for several decades. Public perception on the utilization of recycled materials is that the mixtures become more cost effective and more environmental friendly. This is true when the initial stage of construction of pavements is assessed. However, a mixture that costs less and/or burdens the environment less at the beginning may require more frequent …


Cooling And Packaging Of Accumulators For Formula Sae Electric Car, Hang Yin May 2016

Cooling And Packaging Of Accumulators For Formula Sae Electric Car, Hang Yin

Mechanical and Aerospace Engineering Theses - Archive

Electric car is the future of automotive industry. The performance of the batteries is vital for that of electric cars. Overheating will compromise the performance of batteries, shorten the life span and even damage the battery permanently. So it is crucial to have an efficient packaging and cooling method. This project using Formula SAE Electric car as the testing ground is dedicated to develop the efficient way of thermal and electronic packaging of accumulators for automobiles.


Development And Flight Test Of Moving-Mass Actuated Unmanned Aerial Vehicle, Sampath Reddy Vengate May 2016

Development And Flight Test Of Moving-Mass Actuated Unmanned Aerial Vehicle, Sampath Reddy Vengate

Mechanical and Aerospace Engineering Theses - Archive

Conventional airplane control is achieved by aerodynamic control surfaces by generating moments around all the three axes of the aircraft. Defections of the control surfaces have some disadvantages such as induced drag, increase in radar signature, and exposure to high temperature in high speed applications. As an alternative moment generation mechanism, prior research proposed internal mass-actuation, which is to generate gravitational moment by changing the center of gravity of the aircraft through motion of internal masses within the aircraft. Prior research investigated the feasibility and benefit of internal mass-actuation in airplane control based on simulation analysis. The main focus of …


Numerical Studies On Spin Coating Of Metals, Varun Nanjunda Rao Viswamithra May 2016

Numerical Studies On Spin Coating Of Metals, Varun Nanjunda Rao Viswamithra

Mechanical and Aerospace Engineering Theses - Archive

Spin coating is a surface coating process which involves spreading a liquid dispensed on the center of a rotating substrate. The liquid is discharged using a suitable method on to the substrate rotating at a constant angular speed. The spinning speed is controlled to obtain a coating of desired thickness with faster spinning resulting in thinner coating. The thickness of the coating also depends on the properties of the fluid and other process parameters. Centrifugal force is introduced into the code as radial component of acceleration. The first part of the code solves the continuity and the Navier-Stokes equations, with …


Cfd Analysis And Design Optimization Of Heat Sink For Oil Immersion Cooling, Koushik Epuri May 2016

Cfd Analysis And Design Optimization Of Heat Sink For Oil Immersion Cooling, Koushik Epuri

Mechanical and Aerospace Engineering Theses - Archive

Air cooling is predominant cooling technique employed in most of the data centers. As the demand for High performance computing (HPC) which deploy large concentration of high-end servers (30 kW to 200 kW per rack) is increasing, it is becoming challenging to cool the systems using air cooling. Liquid cooling has significant advantages over air cooling techniques due to higher heat capacities of fluids. Liquid immersion cooling using dielectric and non-corrosive mineral oils is one of the potential alternative to air cooling methods for high density data centers. In this work, we consider a third generation open compute server optimized …


Design And Stiffness Optimization Of Quadri-Directional Composite Grid Lattice Structures, Gajendra Devanga Gangadara May 2016

Design And Stiffness Optimization Of Quadri-Directional Composite Grid Lattice Structures, Gajendra Devanga Gangadara

Mechanical and Aerospace Engineering Theses - Archive

Composite grid structures are rib stiffeners connected to each other rigidly in a pattern or a lattice such that the whole grid pattern has certain smeared stiffness property and has a certain structural behavior. The main focus of this thesis is to design the geometric pattern of a Quadri-directional composite grid lattice such that it has the prescribed stiffness moduli. The research is divided into three phases, in the first phase, the equation for stiffness moduli, the reduced stiffness matrix [Q] and the laminate stiffness matrices [ABD] of the grid pattern is derived for Quadri-directional grid panels. In the second …


Wireless Power Transfer For Medical And Industrial Applications, Minh Quoc Nguyen May 2016

Wireless Power Transfer For Medical And Industrial Applications, Minh Quoc Nguyen

Electrical Engineering Dissertations - Archive

My primary research focuses on wireless power transfer technology utilizing in two different areas: medical and industrial applications. In the medical applications, my research focuses on design and optimization methods for spiral coils utilized for wireless power transfer in wireless medical implant applications. A theoretical model was examined for near field distributions of spiral-type transmitter antennas in both orthogonal components. Finite element simulations were performed to verify the theoretical radiation patterns. Receiver antenna voltages were measured at planes of interest as a means to map field distributions. Theoretical, simulation and experimental results were conducted in the free space and they …


Design And Resistance Factor Calibration Of Pipe Piles In California, Yujie Hu May 2016

Design And Resistance Factor Calibration Of Pipe Piles In California, Yujie Hu

Civil Engineering Theses - Archive

Steel pipe piles, either open ended or close ended, are widely used in the state of California as bridge foundations due to high load bearing capacity, light weight, and outstanding workability. The design methods currently used by Caltrans were developed based on limited field data and are lack of field validations of the recent development of steel pipe piles. In this thesis study, 45 high quality steel pipe pile load tests performed in various soil conditions were collected from Caltrans’ load test data to evaluate available design methods and calibrate the resistance factors of selected design methods. A total of …


Potential Application Of Ultra-High Performance Fiber-Reinforced Concrete With Wet-Mix Shotcrete System In Tunneling, Jean Gamarra May 2016

Potential Application Of Ultra-High Performance Fiber-Reinforced Concrete With Wet-Mix Shotcrete System In Tunneling, Jean Gamarra

Civil Engineering Theses - Archive

In the tunneling industry, shotcrete has been used for several decades. The use of shotcrete or wet-mix spray-on methods allows the application of this method in complex underground profiles and shapes. The need for time efficient spraying methods and constructability for lining coverage opens the door for technologies like steel and synthetic fiber reinforced shotcrete to achieve a uniform and a good quality product. An important advantage of the application of fiber reinforced concrete in shotcrete systems for tunneling is that almost no steel fixing is required. This leads to several other advantages including safer working conditions during excavation, less …


Comparison Of Construction Methods For Building An Underground Freight Transportation In Texas, Niloofar Rezaei May 2016

Comparison Of Construction Methods For Building An Underground Freight Transportation In Texas, Niloofar Rezaei

Civil Engineering Theses - Archive

Freight transportation by trucks constitutes approximately 80% of total freight transportation in Texas and it is expected to approximately double by the year 2040. Social and environmental costs are adverse impacts of moving freights by trucks. Underground Freight Transportation (UFT) significantly reduces these negative impacts and is more sustainable method of freight transportation. UFT includes close-fitting vehicles carrying freight through underground pipelines or tunnels between terminals. The main objective of this research is to compare two construction methods: (1) tunneling using tunnel boring machine (TBM) and (2) tunneling using open-cut. To conduct this research, a comprehensive literature search on various …


Enhancing Productivity By Using Building Information Modeling Applications In Pipeline Construction Projects, Harsha Vardhan Reddy Guduru Penusila May 2016

Enhancing Productivity By Using Building Information Modeling Applications In Pipeline Construction Projects, Harsha Vardhan Reddy Guduru Penusila

Civil Engineering Theses - Archive

Building Information Modeling (BIM) is a technology and associated set of processes to produce, communicate, and analyze building models. BIM is a new concept within the construction industry. The objective of this thesis is to utilize BIM in pipeline construction projects as one of the pioneering steps to reduce rework and delays due to unforeseen conditions. This thesis presents evaluation and recommendations to help pipeline construction industry’s transition from traditional two-dimensional drawings to a BIM management process aiding owners and contractors to develop and implement a basic form of BIM technique to manage their projects. This thesis uses two pipeline …


Enhanced Seismic Performance Of Special Truss Moment Frames And Staggered Truss Framing System For Seismically Active Areas, Sanputt Simasathien May 2016

Enhanced Seismic Performance Of Special Truss Moment Frames And Staggered Truss Framing System For Seismically Active Areas, Sanputt Simasathien

Civil Engineering Dissertations - Archive

Due to their ability to achieve large column-free floor spaces, special truss moment frames (STMFs) and staggered truss frames (STFs) are unique valuable options for structural engineers. However, although STMFs and STFs offer a wide range of structural, architectural, and economical benefits, limited research data is available on the seismic performance of these systems. STMF system is a relatively new type of steel framing system for use in high seismic areas. STMFs dissipate earthquake energy through ductile special segments located near the mid-span of the truss girders, while the other members outside the special segment, including truss members, columns, and …


Investigation Of Strength-Enhancement Mechanism And Size Effect On Ultimate Shear Strength Of Steel Fiber-Reinforced Concrete (Sfrc) Slender Beams, Mohammad Reza Zarrinpour May 2016

Investigation Of Strength-Enhancement Mechanism And Size Effect On Ultimate Shear Strength Of Steel Fiber-Reinforced Concrete (Sfrc) Slender Beams, Mohammad Reza Zarrinpour

Civil Engineering Dissertations - Archive

This research study consists of two separate phases. In the first phase, an experimental study was conducted to identify the shear-enhancement and failure mechanisms behind the ultimate shear strength of steel fiber-reinforced concrete (SFRC) slender beams by utilizing the full field deformation measuring capability of digital image correlation (DIC) technology. A total of 12 large-scale simply supported SFRC and RC beams with a range of heights including 12 in. (305 mm), 18 in. (457 mm), 24 in. (610 mm), 36 in. (915 mm), and 48 in. (1220 mm) were tested under monotonic point load. The greater shear strength in SFRC …


Manipulating The K-Space For Reduction Of Respiratory Induced Motion Artifacts, Maida Ranjbar May 2016

Manipulating The K-Space For Reduction Of Respiratory Induced Motion Artifacts, Maida Ranjbar

Bioengineering Theses - Archive

Respiratory induced motion artifacts, particularly those occurring in the abdomen and lung, pose a hefty problem in current diagnostic MR imaging. Application of images plagued with such artifacts not only hinder diagnosis, but may result in the enforcement of undesirably large safety margins in radiation therapy due to un-captured tumor characteristics that are concealed by the artifact. While several methods such as gated scans, breath-hold scans, variation of the K-Space acquisition trajectory, and reducing the scan time via partial acquisition or parallel imaging have been proposed as a solution, a robust and yet simple to implement remedy still remains to …


Strengthening Of Lightweight Reinforced Concrete Beams Using Carbon Fiber Reinforced Polymers (Cfrp), Tariq Al Jaafreh May 2016

Strengthening Of Lightweight Reinforced Concrete Beams Using Carbon Fiber Reinforced Polymers (Cfrp), Tariq Al Jaafreh

Civil Engineering Dissertations - Archive

This research aimed to investigate the effect of utilizing “Fiber Reinforced Polymer” (FRP) on the light weight concrete beams. The main hypothesis is that such utilization of the FRP will lead to strengthened lightweight beams. The research that has been done on this relationship is somewhat broad in the scope and have mostly focused on the normal-weight concrete. However, only few studies that have considered the light weight concrete. Eight Beams were tested in this research under four point bending test. Two beams were taken as a control beams without any external bonding of Carbon Fiber Reinforced polymer. Another two …


Effect Of Turbulence And Roughness On Coupled Porous-Medium/Free-Flow Exchange Processes, Thomas Fetzer, Kathleen M. Smits, Rainer Helmig Mar 2016

Effect Of Turbulence And Roughness On Coupled Porous-Medium/Free-Flow Exchange Processes, Thomas Fetzer, Kathleen M. Smits, Rainer Helmig

Civil Engineering Faculty Publications - Archive

The interactions between turbulent free flow and flow in a porous medium are of key interest in different fields, e.g., meteorology, agriculture, building physics, and aerospace engineering. Properly understanding the strongly coupled exchange processes between the two domains is crucial to describing these interactions. In (Mosthaf et al. in Water Resources Research 47(10):W10522, 2011. doi:10.1029/2011WR010685), a concept for coupling laminar compositional single-phase free flow to compositional two-phase porous-medium flow under non-isothermal conditions was presented. In this study, the existing coupling concept is first extended to turbulent free-flow conditions. This includes the interface conditions between a Reynolds-averaged Navier–Stokes free flow using …


Dimensionality Reduction Based Optimization Algorithm For Sparse 3-D Image Reconstruction In Diffuse Optical Tomography, Tanmoy Bhowmik, Hanli Liu, Zhou Ye, Soontorn Oraintara Mar 2016

Dimensionality Reduction Based Optimization Algorithm For Sparse 3-D Image Reconstruction In Diffuse Optical Tomography, Tanmoy Bhowmik, Hanli Liu, Zhou Ye, Soontorn Oraintara

Bioengineering Faculty Publications - Archive

No abstract provided.