Current Search: Electrical Circuits (x)
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- Title
- Triggered Sweep Generators Using Modern Integrated Circuits.
- Creator
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Klinger, Arthur Russell, null, null, Engineering
- Abstract / Description
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Florida Technological University College of Engineering Thesis; The oscilloscope is undoubtedly one of the most important tools in any electronics shop. Presently there are many relatively inexpensive oscilloscopes available, but triggered sweep capability is still reserved for those oscilloscopes costing more than 200 - 500 dollars. The goal of this project was to develop a respectably performing triggered sweep system at a low enough cost to allow inclusion of this valuable feature in any...
Show moreFlorida Technological University College of Engineering Thesis; The oscilloscope is undoubtedly one of the most important tools in any electronics shop. Presently there are many relatively inexpensive oscilloscopes available, but triggered sweep capability is still reserved for those oscilloscopes costing more than 200 - 500 dollars. The goal of this project was to develop a respectably performing triggered sweep system at a low enough cost to allow inclusion of this valuable feature in any oscilloscope. Two of the most important specifications of an oscilloscope are the bandwidth of the vertical amplifier, and the maximum sweep frequency. The broad class of "inexpensive oscilloscope" would include those with a maximum vertical response of 500 KHz to 5 MHz , and a maximum sweep rate of 50 KHz to 500 KHz . Most of these oscilloscopes would not have triggered sweep capability. For about double the cost, the next step upward would be a semi- professional triggered - sweep oscilloscope having a typical vertical response of 1511Hz and a sweep to roughly 2 MHz (500 nsec). Using these classifications as guidelines, a "respectably performing" triggered sweep for inexpensive oscilloscopes may be loosely defined as one having a 500 KHz (2 nsec) sweep, triggerable to at least 5 MHz. Depending on actual cost and application , greater or lesser performance could be considered entirely acceptable. A number of design variations are possible, all of which appear to be a fraction of the cost and complexity of previous designs having comparable specifications . Making this possible are integrated circuits in general, and a modern linear IC "timer" in particular. This report first describes this timer, then uses it as the main element in the generation of a linear ramp. Several trigger and gating circuits are then described. Finally, several of these subcircuits are combined to form three (out of many possible) complete triggered sweep generator systems. As an example of the results, the most expensive circuit costs about 15 dollars in single quantity, yet offers 10 volt per 200 nsec sweep rates, trigger capability from OC to above 15 MHz, trigger level and phase control, and blanking pulse output.
Show less - Date Issued
- 1973
- Identifier
- CFR0003511, ucf:53002
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0003511
- Title
- WEB-BASED CIRCUIT DESIGN SIMULATION PACKAGE FOR SOLVING ELECTRICAL ENGINEERING CIRCUITS.
- Creator
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Harb, Shadi, Batarseh, Issa, University of Central Florida
- Abstract / Description
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A Web-based circuit design package has been improved and evaluated to provide students with an enhanced and innovative teaching tools package for the electrical circuit design course. The project objectives can be summarized as follows: 1) developing enhanced problem solving skills using a Web-based environment, 2) developing the design skills and sharpening the critical thinking process, 3) developing a generic and comprehensive teaching/learning circuit package as an extention to the...
Show moreA Web-based circuit design package has been improved and evaluated to provide students with an enhanced and innovative teaching tools package for the electrical circuit design course. The project objectives can be summarized as follows: 1) developing enhanced problem solving skills using a Web-based environment, 2) developing the design skills and sharpening the critical thinking process, 3) developing a generic and comprehensive teaching/learning circuit package as an extention to the Electrical Engineering virtual lab environment, which gives students the capability to practice and experience all the circuit design skills with minimum cost and effort. The project provides the students with an enhanced and powerful graphical computer aided design (CAD) tool by which students can carry out an online simulation of AC and DC designs with the capability to plot simulation results graphically. The proposed prototype is implemented by JAVA, which is used to to implement Web-based applications with different platform support. The project provides students with an enhanced graphical user interface (GUI) by which they can build any electrical circuit using either text or schematic entry format, generate the Netlist, which describes all circuit information (circuit topology, circuit attributes and so on), and simulate the design by parsing the Netlist to CIRML format, which is sent over the network to the remote server. The server will process the CIRML data and run the simulation using PSPICE and eventually send back the simulation results to the client for display.
Show less - Date Issued
- 2004
- Identifier
- CFE0000315, ucf:46316
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000315
- Title
- Energy aware design and analysis for synchronous and asynchronous circuits.
- Creator
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Di, Jia, Yuan, Jiann S., Engineering and Computer Science
- Abstract / Description
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University of Central Florida College of Engineering Thesis; Power dissipation has become a major concern for IC designers. Various low power design techniques have been developed for synchronous circuits. Asynchronous circuits, however have gained more interests recently due to their benefits in lower noise, easy timing control, etc. But few publications on energy reduction techniques for asynchronous logic are available. Power awareness indicates the ability of the system power to scale...
Show moreUniversity of Central Florida College of Engineering Thesis; Power dissipation has become a major concern for IC designers. Various low power design techniques have been developed for synchronous circuits. Asynchronous circuits, however have gained more interests recently due to their benefits in lower noise, easy timing control, etc. But few publications on energy reduction techniques for asynchronous logic are available. Power awareness indicates the ability of the system power to scale with changing conditions and quality requirements. Scalability is an important figure-of-merit since it allows the end user to implement operational policy just like the user of mobile multimedia equipment needs to select between better quality and longer battery operation time. This dissertation discusses power /energy optimization and performs analysis on both synchronous and asynchronous logic.
Show less - Date Issued
- 2004
- Identifier
- CFR0001720, ucf:52913
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0001720
- Title
- Multi-Physics Model of Key Components In High Efficiency Vehicle Drive.
- Creator
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Lin, Shao Hua, Wu, Xinzhang, Sundaram, Kalpathy, Wahid, Parveen, Wei, Lei, Chow, Louis, University of Central Florida
- Abstract / Description
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Hybrid Electric Vehicles (HEVs) and Electric Vehicles (EVs) are crucial technologies for the automotive industry to meet society's demands for cleaner, more energy efficient transportation. Meeting the need to provide power which sustains HEVs and EVs is an immediate area of concern that research and development within the automotive community must address. Electric batteries and electrical motors are the key components in HEV and EV power generation and transmission, and their performance...
Show moreHybrid Electric Vehicles (HEVs) and Electric Vehicles (EVs) are crucial technologies for the automotive industry to meet society's demands for cleaner, more energy efficient transportation. Meeting the need to provide power which sustains HEVs and EVs is an immediate area of concern that research and development within the automotive community must address. Electric batteries and electrical motors are the key components in HEV and EV power generation and transmission, and their performance plays very important role in the overall performance of the modern high efficiency vehicles. Therefore, in this dissertation, we are motivated to study the electric batteries, interior permanent motor (IPM), in the context of modern hybrid electric/electric drive systems, from both multi-physics and system level perspectives. Electrical circuit theory, electromagnetic Finite Element Analysis (FEA), and Computational Fluid Dynamic (CFD) finite volume method will be used primarily in this work. The work has total of five parts, and they are introduced in the following.Firstly, Battery thermal management design is critical in HEV and EV development. Accurate temperature distribution of the battery cells during vehicle operation is required for achieving optimized design. We propose a novel electrical-thermal battery modeling technique that couples a temperature dependent battery circuit model and a physics-based CFD model to meet this need. The electrical circuit model serves as a heat generation mechanism for the CFD model, and the CFD model provides the temperature distribution of the battery cells, which can also impact the heat generation of the electrical battery model. In this part of work, simulation data has been derived from the model respective to electrical performance of the battery as well as the temperature distribution simultaneously in consideration of the physical dimensions, material properties, and cooling conditions. The proposed model is validated against a battery model that couples the same electrical model with a known equivalent thermal model.Secondly, we propose an accurate system level Foster network thermal model. The parameters of the model are extracted from step responses of the CFD battery thermal model. The Foster network model and the CFD model give the same results. The Foster network can couple with battery circuit model to form an electric-thermal battery model for system simulation.Thirdly, IPM electric machines are important in high performance drive systems. During normal operations, irreversible demagnetization can occur due to temperature rise and various loading conditions. We investigate the performance of an IPM using 3d time stepping electromagnetic FEA considering magnet's temperature dependency. Torque, flux linkage, induced voltage, inductance and saliency of the IPM will be studied in details. Finally, we use CFD to predict the non-uniform temperature distribution of the IPM machine and the impact of this distribution on motor performance. Fourthly, we will switch gear to investigate the IPM motor on the system level. A reduced order IPM model is proposed to consider the effect of demagnetization of permanent magnet due to temperature effect. The proposed model is validated by comparing its results to the FEA results.Finally, a HEV is a vehicle that has both conventional mechanical (i.e. internal combustion engine) and electrical propulsion systems. The electrical powertrain is used to work with the conventional powertrain to achieve higher fuel economy and lower emissions. Computer based modeling and simulation techniques are therefore essential to help reduce the design cost and optimize system performance. Due to the complexity of hybrid vehicles, multi-domain modeling ability is preferred for both component modeling and system simulation. We present a HEV library developed using VHDL-AMS.
Show less - Date Issued
- 2013
- Identifier
- CFE0005024, ucf:50016
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005024
- Title
- Nonlinear dynamic modeling, simulation and characterization of the mesoscale neuron-electrode interface.
- Creator
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Thakore, Vaibhav, Hickman, James, Mucciolo, Eduardo, Rahman, Talat, Johnson, Michael, Behal, Aman, Molnar, Peter, University of Central Florida
- Abstract / Description
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Extracellular neuroelectronic interfacing has important applications in the fields of neural prosthetics, biological computation and whole-cell biosensing for drug screening and toxin detection. While the field of neuroelectronic interfacing holds great promise, the recording of high-fidelity signals from extracellular devices has long suffered from the problem of low signal-to-noise ratios and changes in signal shapes due to the presence of highly dispersive dielectric medium in the neuron...
Show moreExtracellular neuroelectronic interfacing has important applications in the fields of neural prosthetics, biological computation and whole-cell biosensing for drug screening and toxin detection. While the field of neuroelectronic interfacing holds great promise, the recording of high-fidelity signals from extracellular devices has long suffered from the problem of low signal-to-noise ratios and changes in signal shapes due to the presence of highly dispersive dielectric medium in the neuron-microelectrode cleft. This has made it difficult to correlate the extracellularly recorded signals with the intracellular signals recorded using conventional patch-clamp electrophysiology. For bringing about an improvement in the signal-to-noise ratio of the signals recorded on the extracellular microelectrodes and to explore strategies for engineering the neuron-electrode interface there exists a need to model, simulate and characterize the cell-sensor interface to better understand the mechanism of signal transduction across the interface. Efforts to date for modeling the neuron-electrode interface have primarily focused on the use of point or area contact linear equivalent circuit models for a description of the interface with an assumption of passive linearity for the dynamics of the interfacial medium in the cell-electrode cleft. In this dissertation, results are presented from a nonlinear dynamic characterization of the neuroelectronic junction based on Volterra-Wiener modeling which showed that the process of signal transduction at the interface may have nonlinear contributions from the interfacial medium. An optimization based study of linear equivalent circuit models for representing signals recorded at the neuron-electrode interface subsequently proved conclusively that the process of signal transduction across the interface is indeed nonlinear. Following this a theoretical framework for the extraction of the complex nonlinear material parameters of the interfacial medium like the dielectric permittivity, conductivity and diffusivity tensors based on dynamic nonlinear Volterra-Wiener modeling was developed. Within this framework, the use of Gaussian bandlimited white noise for nonlinear impedance spectroscopy was shown to offer considerable advantages over the use of sinusoidal inputs for nonlinear harmonic analysis currently employed in impedance characterization of nonlinear electrochemical systems. Signal transduction at the neuron-microelectrode interface is mediated by the interfacial medium confined to a thin cleft with thickness on the scale of 20-110 nm giving rise to Knudsen numbers (ratio of mean free path to characteristic system length) in the range of 0.015 and 0.003 for ionic electrodiffusion. At these Knudsen numbers, the continuum assumptions made in the use of Poisson-Nernst-Planck system of equations for modeling ionic electrodiffusion are not valid. Therefore, a lattice Boltzmann method (LBM) based multiphysics solver suitable for modeling ionic electrodiffusion at the mesoscale neuron-microelectrode interface was developed. Additionally, a molecular speed dependent relaxation time was proposed for use in the lattice Boltzmann equation. Such a relaxation time holds promise for enhancing the numerical stability of lattice Boltzmann algorithms as it helped recover a physically correct description of microscopic phenomena related to particle collisions governed by their local density on the lattice. Next, using this multiphysics solver simulations were carried out for the charge relaxation dynamics of an electrolytic nanocapacitor with the intention of ultimately employing it for a simulation of the capacitive coupling between the neuron and the planar microelectrode on a microelectrode array (MEA). Simulations of the charge relaxation dynamics for a step potential applied at t = 0 to the capacitor electrodes were carried out for varying conditions of electric double layer (EDL) overlap, solvent viscosity, electrode spacing and ratio of cation to anion diffusivity. For a large EDL overlap, an anomalous plasma-like collective behavior of oscillating ions at a frequency much lower than the plasma frequency of the electrolyte was observed and as such it appears to be purely an effect of nanoscale confinement. Results from these simulations are then discussed in the context of the dynamics of the interfacial medium in the neuron-microelectrode cleft. In conclusion, a synergistic approach to engineering the neuron-microelectrode interface is outlined through a use of the nonlinear dynamic modeling, simulation and characterization tools developed as part of this dissertation research.
Show less - Date Issued
- 2012
- Identifier
- CFE0004797, ucf:49718
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004797