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Mems Piezoresistive Pressure Sensor On Flexible Substrates Using Nichrome And Cnt/Polyimide Nanocomposites Piezoresistors, Gaviraj Nadvi 2010 University of Texas at Arlington

Mems Piezoresistive Pressure Sensor On Flexible Substrates Using Nichrome And Cnt/Polyimide Nanocomposites Piezoresistors, Gaviraj Nadvi

Electrical Engineering Theses

Micro pressure sensors using nichrome as piezoresistor were fabricated on silicon and flexible substrates. The pressure sensors on flexible substrate can be used for prosthetic skin applications. The devices were successfully tested using different methods.Micromachined pressure/force sensors using nickel chromium piezoresistors have been investigated experimentally and through finite element mesh analysis. The pressure/force sensors were designed using a suspended aluminum oxide membrane with optimally placed piezoresistors to measure the strain in the membrane when deflected with an applied force or pressure. Different devices, each with varying size and shape of both the membrane and the piezoresistors were designed, fabricated, and …


Tutorial On Network Quality And Ims Services Used In Lte, Ayush Maheshwari 2010 University of Texas at Arlington

Tutorial On Network Quality And Ims Services Used In Lte, Ayush Maheshwari

Electrical Engineering Theses

3rd Generation or 3G technologies like WCDMA, HSPA and GPRS are very advanced technologies in themselves. They allow data downlink speeds of up to 7Mbps and will soon be offering up to 14Mbps. The number of people using these networks has crossed 70 million users worldwide and with ever increasing users we need to provide a solution to handle the new and improved services which are being designed daily to work on mobile devices. Long Term Evolution (LTE), will be one of the two technologies which will meet the ITU's IMT-Advanced requirements for 4G technologies. 3G Partnership Project (3GPP) is …


Charge Pump Circuit, Paras Shah 2010 University of Texas at Arlington

Charge Pump Circuit, Paras Shah

Electrical Engineering Theses

The sole aim of this work is to show how to generate higher voltages greater than the power supply voltage. This idea is implemented using transistors and capacitors on silicon and is called a charge pump circuit. A charge pump circuit is implemented as a voltage doubler circuit in this work using 0.25um gate length technology. A 6-stage Dickson charge pump circuit was designed to produce a 15 V output from a 5 V supply using two phase non-overlapping clock signals that drive the charge pump. It also describes the advanced architectures with complex circuit design and dynamic techniques for …


Develpoment Of An Electronically Controlled Cold Plasma Reformer For Hydrogen Harvest From Bio-Fuels, Job Brunet 2010 University of Texas at Arlington

Develpoment Of An Electronically Controlled Cold Plasma Reformer For Hydrogen Harvest From Bio-Fuels, Job Brunet

Electrical Engineering Theses

The energy demand on the world market due to the limited resources has forced governments and scientists to find an alternative source of fuel to ease the burden on its populous and environment. Moreover, the rate of global warming is increasing with the rate of carbon dioxide released from emissions from coal burning power plants and also from vehicle exhaust. This trend of burn now and fix later has to end and a new source of fuel must be developed. Wind, solar, and even nuclear are great substitutes for reducing the global pollution but a new tangible fuel is required. …


A Tutorial On Lte Evolved Utran (Eutran) And Lte Self Organizing Networks (Son), Dhruv Sunil Shah 2010 University of Texas at Arlington

A Tutorial On Lte Evolved Utran (Eutran) And Lte Self Organizing Networks (Son), Dhruv Sunil Shah

Electrical Engineering Theses

The third-generation (3G) cellular communication technology, Universal Mobile Terrestrial System (UMTS), based on Wideband Code-Division Multiple Access (WCDMA), has been widely deployed all over the world providing faster download speeds for data (packet) communications. To further improve the throughput and overall performance of the cellular communication system established by UMTS, the Third Generation Partnership Project (3GPP) in November 2004 launched an ambitious project called the Long Term Evolution (LTE) of UMTS. This would ensure the continued competitiveness of the UMTS in the future. The technical specifications of the LTE project are formally known as the Evolved UMTS Terrestrial Radio Access …


Detection And Severity Classification Of Rotor Imbalance Faults In Induction Machines, Himanshu Jain 2010 University of Texas at Arlington

Detection And Severity Classification Of Rotor Imbalance Faults In Induction Machines, Himanshu Jain

Electrical Engineering Theses

As world economy continues to globalize, increased competition has lead to a reduction in profit margins. To remain competitive in such an economy, an industry needs to reduce the downtime of critical components even for maintenance purposes. However, this should not jeopardize the genuine maintenance needs of the equipments. In other words, an optimized maintenance strategy is needed, in which maintenance is performed only when a need for it arises; unlike the currently popular periodic maintenance. Condition based Maintenance (CBM) is one such strategy. Induction machines are work horse of an industry. Their criticality to industry may be gauged by …


Passive Rf Sensors And Wireless Sensor Interrogation, Srikar Deshmukh 2010 University of Texas at Arlington

Passive Rf Sensors And Wireless Sensor Interrogation, Srikar Deshmukh

Electrical Engineering Theses

Recently, a new type of passive sensor called the antenna sensor has been developed. The antenna sensor incorporates a patch antenna as the sensing element as well as the data transmitting element. Physical factors such as strain and ground plane crack cause the patch antenna resonant frequency to change. By measuring the change in patch antenna resonant frequency these physical factors can be quantified.Conventional resonant frequency measurement methods require a wired connection to the antenna sensor. The wireless interrogation technique eliminates this requirement while offering all the advantages that a wireless sensor interface offers over a wired sensor interface. In …


An Ultra Wide Band Cmos Low Noise Amplifier Design, Nahusha Bhadravati Mohankumar 2010 University of Texas at Arlington

An Ultra Wide Band Cmos Low Noise Amplifier Design, Nahusha Bhadravati Mohankumar

Electrical Engineering Theses

An RF ultra wide band low noise amplifier designed for the frequency range of 12-18 GHz of operation is presented in this paper. The low noise amplifier is designed using the state-of-the-art complementary metal oxide semiconductor 45 nm technology. Berkeley's Predictive Technology Model (PTM) is used to generate a fairly accurate mathematical model and the SPICE data is implemented into the BSIM 4 version of the Advanced Design Systems (ADS) program. The low noise design strategy is mainly based on the analysis of high frequency CMOS operation. This LNA has two stages: the first stage is a RL feedback amplifier …


A Comparison Method To Evaluate Motion Splicing Techniques, George Thekkanath Raphael 2010 University of Texas at Arlington

A Comparison Method To Evaluate Motion Splicing Techniques, George Thekkanath Raphael

Electrical Engineering Theses

The development of methods for the re-use and modification of motion data is an activearea of research. Among these methods, we find automatic techniques to generate a spliced motion by combining different actions recorded in separate sessions. Motion splicing allows capturing motion independently and later combining them to create a new natural looking motion. Even though there have been a lot of research on motion editing techniques, less focus has been given to evaluate these edited motions. In this thesis, we present a novel methodology to quantitatively evaluate the synthesized motion generated by different motion editing techniques. We implemented three …


Low Complexity H.264 Encoder Using Machine Learning., Thejaswini Purushotham 2010 University of Texas at Arlington

Low Complexity H.264 Encoder Using Machine Learning., Thejaswini Purushotham

Electrical Engineering Theses

H.264 is currently one of the most widely accepted video coding standards in the industry. Several software and hardware solutions for the H.264 video encoder exist in the market at present. H.264 is used in such applications as Blu-ray Disc, videos on the internet, digital video broadcast, direct-broadcast satellite television service, cable television services, and real-time videoconferencing. This thesis uses the WEKA (Waikato Environment for Knowledge Analysis) tool to generate the classification rule. WEKA is detailed in Chapter 3. The input attributes to the WEKA have been calculated from the video sequence to be encoded. The procedure has been elaborated …


A Ph Sensor Based On A Flexible Substrate, Wen-Ding Huang 2010 University of Texas at Arlington

A Ph Sensor Based On A Flexible Substrate, Wen-Ding Huang

Electrical Engineering Dissertations

pH sensor is an essential component used in many chemical, food, and bio-material industries. Conventional glass electrodes have been used to construct pH sensors, however, have some disadvantages. Glass electrodes are easily affected by alkaline or HF solution, they require a high input impedance pH meter, they often exhibit a sluggish response. In some specific applications, it is also difficult to use glass electrodes for in vivo biomedical or food monitoring applications due to the difficulty of size miniaturization, planarization and polymerization based on current manufacturing technologies. In this work, we have demonstrated a novel flexible pH sensor based on …


Position Sensorless Control Of A Magnetically Levitated (Maglev) System, Esteban Ricardo Noboa 2010 University of Texas at Arlington

Position Sensorless Control Of A Magnetically Levitated (Maglev) System, Esteban Ricardo Noboa

Electrical Engineering Dissertations

The main focus of this investigation is the development and implementation of a sensorless position estimation method and hysteresis position controller for a laboratory-based Maglev system. The proposed estimation method and controller are first validated through modeling and simulation. This sensorless scheme makes use of the maglev system's magnetic signature, namely, its inductance and requires only active phase current measurements. These measurements are then used along with the phase voltage equation to estimate position information that is in a one-to-one correspondence with the system's inductance. The theoretical aspects of the sensorless scheme are described. Finite element analysis (FEA) as well …


Distribution Network Contingency Analysis And Contingency Detection With The Consideration Of Load Models, Qiaohui Hu 2010 University of Texas at Arlington

Distribution Network Contingency Analysis And Contingency Detection With The Consideration Of Load Models, Qiaohui Hu

Electrical Engineering Dissertations

The electric utility market environment has changed quite radically during recent years due to the process of deregulation. This has changed the asset management towards a capital controlled business where owners are trying to maximize their profits with cost optimization. To keep up with the increase demands on high reliability and high quality delivery systems, many utilities endeavor to rationalize their system operations with more intelligent control schemes and facilities. A lot of issues under uncertainty such as load growth, quality of supply and environmental impact affect the reliability of the distribution system. Power outage is the most serious challenge …


Development Of Su-8 And Pdms Miniatured Boats And Flotillas, Hao Li 2010 University of Texas at Arlington

Development Of Su-8 And Pdms Miniatured Boats And Flotillas, Hao Li

Electrical Engineering Dissertations

In this work, we developed miniaturized SU-8 and PDMS miniaturized boats and flotillas, and explored their designs, fabrication, actuation, motions and driving mechanisms. Like large-scale boats and flotillas, these miniaturized boat and flotillas can be potentially applied to transport designed targets to desired locations in small fluidic systems. They may also be employed as mixers, rotators and so on. We first develop a SU-8 boat, and studied its design, fabrication, actuation and motions. In three types of tests conducted on water free surfaces of different heights in a 30-cm-long channel, the microboat had a speed in the order of 0.1 …


Light Trapping And Absorption Enhancement For High Performance Solar Cells And Infrared Photodetectors, Li Chen 2010 University of Texas at Arlington

Light Trapping And Absorption Enhancement For High Performance Solar Cells And Infrared Photodetectors, Li Chen

Electrical Engineering Dissertations

This dissertation presents the work on light trapping and absorption enhancement in solar cells and infrared photodetectors. Hemispherical microstructure based omni-directional anti reflection (Omni-AR) coating has been designed and developed for solar cells, based on rigorous coupled-wave analysis (RCWA) and convective coating process. Omni-AR coating enhances light absorption in solar cells, due to the reduced reflection on the structured solar cell surfaces, and the increased optical path length (OPL) inside the solar cells. Omni-AR coating has been demonstrated as a cost-effective light trapping approach for different material systems, with very low reflection and high transmission over a large range of …


Real Time Condition Monitoring Of Chemical Batteries, Anahita Banaei 2010 University of Texas at Arlington

Real Time Condition Monitoring Of Chemical Batteries, Anahita Banaei

Electrical Engineering Dissertations

Li-Ion batteries are suitable rechargeable choices for electric and hybrid electric vehicle (EV/HEV) applications due to their relatively high level of energy and power density. One of the important issues in automotive batteries is to monitor their online state-of-charge (SOC) and state-of-health (SOH).Hence, development of an efficient method for monitoring their online state-of-charge (SOC) and state-of-health (SOH) is of high importance for vehicular applications. Open circuit voltage, as one parameter used for predicting the SOC of the battery, is not readily available during charge and discharge cycles. A wide variety of research has been done on SOC and SOH estimation …


Multi-Wavelength All-Optical 2r Regeneration, Pallavi Govind Patki 2010 University of Texas at Arlington

Multi-Wavelength All-Optical 2r Regeneration, Pallavi Govind Patki

Electrical Engineering Dissertations

We experimentally demonstrate, for the first time to our knowledge, simultaneous all-optical 2R regeneration of multiple WDM channels. In the recent work [1], our group has proposed an all-optical 2R regeneration scheme capable of handling multiple WDM channels simultaneously. Our proposed multi-channel regenerator is a modified configuration of Mamyshev's 2R regenerator [2], in which a conventional highly-nonlinear-fiber (HNLF) is replaced by a novel dispersion-managed nonlinear medium. The proposed multi-channel regeneration scheme uses multiple concatenated dispersion-managed sections, where each dispersion-managed section contains a piece of HNLF and a periodic-group-delay device (PGDD). For the proof-of-principle demonstration of the regenerator we have built …


Zeolite Synthesised From Fused Coal Fly Ash At Low Temperature Using Seawater For Crystallization, Claudia Belviso, Francesco Cavalcante, Antonio Lettino, Saverio Fiore 2010 Laboratory of Environmental and Medical Geology, IMAA–CNR, Tito Scalo (PZ), 85050, Italy

Zeolite Synthesised From Fused Coal Fly Ash At Low Temperature Using Seawater For Crystallization, Claudia Belviso, Francesco Cavalcante, Antonio Lettino, Saverio Fiore

Coal Combustion and Gasification Products Journal Archive

A sample of coal fly ash from an Italian thermoelectric power plant was used in order to synthesize zeolite by hydrothermal activation after a pre-treatment fusion with NaOH. The experiments involved were performed at different temperatures of crystallization, ranging from 35 up to 60uC, with seawater and distilled water, separately, during hydrothermal process. A comparison between the results obtained from the use of the different kinds of water showed that at low temperature (35–40 uC) the synthesis yield of zeolite X is higher using seawater as crystallizing agent than using distilled water. This implies a possible application for seawater in …


Solid-State Tunneling Spectroscopy Of Individual Quantum Dots, Ramkumar Subramanian 2010 University of Texas at Arlington

Solid-State Tunneling Spectroscopy Of Individual Quantum Dots, Ramkumar Subramanian

Material Science and Engineering Dissertations

Quantum dots are gaining importance for their potential applications in the fields of energy harvesting, bio-labeling and treatment, in opto-electronic devices and in photonic devices. For all these applications, it is imperative to know their electronic structure. Although currently several spectroscopic techniques exist to study the electronic structure of these quantum dots, they are accompanied by other effects and do not give purely the electronic structure of the individual quantum dot. The main goals of this research are to:o To study the energy level structure of `single' quantum dots.o Develop a new spectroscopic technique that allows the measurement of the …


Nanoparticle Bridge Dna Biosensor, Hong-Wen Huang 2010 University of Texas at Arlington

Nanoparticle Bridge Dna Biosensor, Hong-Wen Huang

Material Science and Engineering Dissertations

A new DNA sensing method is demonstrated in which DNA hybridization events lead to the formation of nanoparticle satellites that bridge two electrodes and are detected electrically. The hybridization events are exclusively carried out only on specific locations, the surfaces of C-ssDNA modified 50 nm GNPs. The uniqueness of this work is that only a small number of T-ccDNA molecules (<10) is required to form the nanoparticle satellites, allowing ultra-sensitive DNA sensing. The principle of this new DNA sensing technique has been demonstrated using target DNA and three-base-pair-mismatched DNA in 20nM concentrations. Three single-stranded DNA (ssDNA) system is used in our experiment which includes Capture-ssDNA (C-ssDNA), Target-ssDNA (T-ssDNA) and Probe-ssDNA (P-ssDNA). Both C-ssDNA and P-ssDNA are modified by a thiol group and can hybridize with different portions of T-ssDNA. T-ssDNA requires no modification in three ssDNA system, which is beneficial in many applications. C-ssDNA modified 50nm gold nanoparticle (C-50au) and P-ssDNA modified 30nm gold nanoparticle (P-30au) are prepared through the reaction of thiol-gold chemical bonding between thiolated ssDNA and gold nanoparticle (GNP) (C-ssDNA with 50nm GNP, P-ssDNA with 30nm GNP). We controllably place the C-50au only on the SiO2 band surface (~ 90nm width) between two gold electrodes (source and drain electrodes) by forming positively- and negatively-charged self-assembled monolayers (SAMs) on SiO2 and gold surface, respectively. DNA modified GNP is negatively charged due to ionization of phosphate group on DNA back bone. C-50au therefore is negatively charged and can only be attracted toward SiO2 area (repelled by negatively charged gold electrode surface). The amine group of positively-charged SAMs on SiO2 surface is then passivated by converting to non-polar methyl functional group after C-50au placement. P-30au is first hybridized with T-ssDNA in the solution phase (T-P-30au formed) and is introduced into DNA detection device in which C-50au are immobilized on ~90nm width SiO2 band (between two gold electrodes). The passivation step ensures every T-P-30au are attached only to C-50au through hybridization (T-P-30au will not be attracted toward SiO2 surface or gold electrodes). GNP bridges are formed across the electrodes and provide an electrical path between two gold electrodes.We ensure that every T-P-30au only hybridizes on the surface of C-50au by (1) accurately controlling C-50au placement between two gold electrodes, (2) passivating positively-charged SAMs on SiO2 surface after C-50au immobilization. When T-P-30au hybridize with C-50au on ~90nm wide SiO2 surface, GNP bridges form and provide an electrical path between two gold electrodes even with only a few hybridization events. Experimental results show that even a few GNP bridges formed on SiO2 band can provide a significant conductance change from an open circuit to a conductive circuit (current = 0.5 uA at voltage = 0.1 V with four GNP bridge). We also used 3-base-pair-mismatched ssDNA (3mm-ssDNA) as a control experiment, which always resulted in an open circuit (no GNP bridge formed). Our detection device is compatible with current CMOS fabrication technology and can be manufactured on a wafer scale. The direct electrical output of this DNA detection technique provides a promising basis for high-throughput screening (can be fabricated on a wafer scale) with no expensive equipment required.


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