Electrical and Computer Engineering Commons^™

Proportional Feedback Control Of Duty Cycle For Dc Hybrid Active Power Filter, Govind N. Malleichervu

University of Kentucky Master's Theses

This thesis deals with the design and implementation of a feedback control scheme for a DC Hybrid Active Power Filter used to filter harmonics from a Switched Reluctance Motor (SRM) Drive load. Power electronic systems are non-linear & dynamic [1,3,5]. Power electronic systems employ switching circuits to maximize their efficiency at the penalty that switching circuits generate electrical noise called ripple current and voltage or conducted electromagnetic interference (EMI). The ripple current drawn by the power electronic systems needs to be attenuated to an acceptable level. Filters attenuate this to an acceptable level. Traditionally filters with passive inductors and capacitors …

An Effective Cache For The Anywhere Pixel Router, Vijai Raghunathan

Theses and Dissertations--Electrical and Computer Engineering

Designing hardware to output pixels for light field displays or multi-projector systems is challenging owing to the memory bandwidth and speed of the application. A new technique of hardware that implements ‗anywhere pixel routing‘ was designed earlier at the University of Kentucky. This technique uses hardware to route pixels from input to output based upon a Look up Table (LUT). The initial design suffered from high memory latency due to random accesses to the DDR SDRAM input buffer. This thesis presents a cache design that alleviates the memory latency issue by reducing the number of random SDRAM accesses.

The cache …

Dynamic Voltage Scaling For Priority-Driven Scheduled Distributed Real-Time Systems, Chenxing Wang

University of Kentucky Doctoral Dissertations

Energy consumption is increasingly affecting battery life and cooling for real- time systems. Dynamic Voltage and frequency Scaling (DVS) has been shown to substantially reduce the energy consumption of uniprocessor real-time systems. It is worthwhile to extend the efficient DVS scheduling algorithms to distributed system with dependent tasks. The dissertation describes how to extend several effective uniprocessor DVS schedul- ing algorithms to distributed system with dependent task set. Task assignment and deadline assignment heuristics are proposed and compared with existing heuristics concerning energy-conserving performance. An admission test and a deadline com- putation algorithm are presented in the dissertation for dynamic …

Packet-Switching Network With Symmetrical Topology And Method Of Routing Packets, Nader F. Mir

Electrical and Computer Engineering Faculty Patents

A mesh network for routing a plurality of data segments therethrough, each of the data segments containing address information. The network includes: a first, second, and third switch element each having a respective external input for routing data segments into the network and a respective external output for routing data segments out of the network; a bi-directional coupling between each of the switch elements; and a first controller for interrogating the address information of each of the data segments inbound into the first switch element. The exit pathway for any inbound data segment received by a switch element is selected …

Optimal Phase Measuring Profilometry Techniques For Static And Dynamic 3d Data Acquisition, Veeraganesh Yalla

University of Kentucky Doctoral Dissertations

Phase measuring Profilometry (PMP) is an important technique used in 3D data acquisition. Many variations of the PMP technique exist in the research world. The technique involves projecting phase shifted versions of sinusoidal patterns with known frequency. The 3D information is obtained from the amount of phase deviation that the target object introduces in the captured patterns. Using patterns based on single frequency result in projecting a large number of patterns necessary to achieve minimal reconstruction errors. By using more than one frequency, that is multi-frequency, the error is reduced with the same number of total patterns projected as in …

Processor Microarchitecture For Implementation Of Ephemeral State Processing Within Network Routers, Muthulakshmi Muthukumarasamy

Theses and Dissertations--Electrical and Computer Engineering

The evolving concept of Ephemeral State Processing (ESP) is overviewed. ESP allows development of new scalable end-to-end network user services. An evolving macro-level language is being developed to support ESP at the network node level. Three approaches for implementing ESP services at network routers can be considered. One approach is to use the existing processing capability within commercially available network routers. Another approach is to add a small scale existing ASIC based general-purpose processor to an existing network router. This thesis research concentrates on a third approach of developing a special-purpose programmable Ephemeral State Processor (ESPR) Instruction Set Architecture (ISA) …

Finger Mouse And Text-To-Speech Application As Additions To The Smart Wheelchair, Karla Conn

Kaleidoscope

The smart wheelchair project is a unique investigation into the possibilities of helping the impaired navigate in a mobile chair. Many disabled people who need the help of a wheelchair to move about also need help communicating orally. This project allows the “walking” wheelchair to do some “talking.” A communication program for the wheelchair was developed, as well as a finger mouse that was implemented into all the programs. The finger mouse is a switch button small enough to wear on one’s finger. When the button is pressed, a signal is sent out from the transmitter and picked up by …

Fault Tolerant Operation Of Field Programmable Gate Arrays, Miron Abramovici, Charles E. Stroud

Electrical and Computer Engineering Faculty Patents

A method of fault tolerant reconfiguration and operation of a field programmable gate array (FPGA) during normal on-line operation includes selecting a programmable logic block as a programmable logic block under test, testing the programmable logic block under test, and detecting the existence of any faults in the programmable logic block under test. During testing, the programmable logic block under test is repeatedly reconfigured in order to test the programmable logic block completely in all possible modes of operation. Based on the results of the test, a test result indication is sent to a controller in communication with a memory …

Method Of Testing And Diagnosing Field Programmable Gate Arrays, Miron Abramovici, Eric Seng-Kar Lee, Charles Eugene Stroud

Electrical and Computer Engineering Faculty Patents

A method of testing field programmable gate arrays (FPGAs) includes establishing a first group of programmable logic blocks as test pattern generators or output response analyzers and a second group of programmable logic blocks as blocks under test. This is followed by generating test patterns and comparing outputs of two blocks under test with one output response analyzer. Next is the combining of results of a plurality of output response analyzers utilizing an iterative comparator in order to produce a pass/fail indication. The method also includes the step of reconfiguring each block under test so that each block under test …

Maintenance Registers With Boundary Scan Interface, Shianling Wu, Ramesh Karri, Charles Eugene Stroud

Electrical and Computer Engineering Faculty Patents

Concurrent Fault Detector Circuits (CFDCs) are test components of a main system, e.g. an Application Specific Integrated Circuit, and provide the results of the tests in parallel to at least one Error Source Register (ESR). Instead of reading out the ESR in parallel, its contents are copied to a serial shadow register so the contents can be read out in series to an error correcting application, thus reducing the number of output pins and the burden on resources of the main system. The ESR's receipt and transfer of information is under the control of a Boundary Scan Interface. In one …

Method And System For Gas Metal Arc Welding, Yuming Zhang, Liguo E

Electrical and Computer Engineering Faculty Patents

An improved method of gas metal arc welding (GMAW) is disclosed. The method includes utilizing a pulsed current having a variable waveform to ensure the detachment of one-droplet-per-pulse of current. During the welding process, the current is sufficient to produce a droplet at the end of a consumable electrode wire. After the droplet reaches a desired size, the current is lowered to induce an oscillation in the droplet. The current is then increased which, in combination with the momentum created by the oscillation, effects droplet detachment. The oscillation may be monitored by observing the arc voltage to determine a preferred …

Method For Testing Field Programmable Gate Arrays, Charles E. Stroud, Miron Abramovici

Electrical and Computer Engineering Faculty Patents

A method of testing field programmable gate arrays (FPGAs) includes the step of configuring programmable logic blocks of the FPGAs for completing a built-in self-test. This is followed by the steps of initiating the built-in self-test, generating test patterns with the programmable logic blocks and analyzing a resulting response to produce a pass/fail indication with the programmable logic blocks. More specifically, the configuring step includes establishing a first group of programmable logic blocks as test pattern generators and output response analyzers and a second group of programmable logic blocks as blocks under test. The blocks under test are then repeatedly …

Method For Testing Field Programmable Gate Arrays, Charles E. Stroud, Miron Abramovici

Electrical and Computer Engineering Faculty Patents

A method of testing field programmable gate arrays (FPGAs) includes the step of configuring programmable logic blocks of the FPGAs for completing a built-in self-test. Specifically, the FPGA under test may be configured to act as an iterative logic array wherein a first group of programmable logic blocks are configured as test pattern generators, output response analyzers and helper cells, and a second group of programmable logic blocks are configured as blocks under test. The blocks under test are then repeatedly reconfigured in order to completely test each block under test in all possible modes of operation. The first and …

Method Of Arc Welding Using Dual Serial Opposed Torches, Yuming Zhang, Shaobin Zhang

Electrical and Computer Engineering Faculty Patents

An improved method of arc welding uses a single power supply connected to opposed welding torches placed on both sides of a workpiece. Each torch is connected to a different polarity lead of the power supply and forms a separate arc with the workpiece. When a current is supplied to the first torch, it is guided from the first electrode, through the first arc, the workpiece, the second arc, and to the electrode of the second torch. This guiding function improves the penetration, concentration, as well as the directional stability of the arc. This permits the effective and efficient welding …

Modeling And Simulation Of Manufacturing Systems Under Signal Kanban Policies, Lawrence E. Holloway

Electrical and Computer Engineering Presentations

A signal kanban system is used to order the production of various parts by processes with lengthy setup times, such as in metal stamping or injection molding. In this paper, we explore the behavior of signal kanban systems using simulations of systems producing two part types. Such simple models allows a visualization of the changes in the inventories of these parts under the signal kanban system. We consider the operation of the common fixed-batch signal kanban system, and a variation that we refer to as a fixed-fill policy. These policies are investigated under variations in demand, occasional disruptions in production, …

Field Calibration Of A Transient Model For Broiler Misting, Richard S. Gates, Douglas G. Overhults, Robert W. Bottcher, Shu Hui Zhang

Biosystems and Agricultural Engineering Faculty Publications

A transient model to predict temperature within a tunnel ventilated broiler house during misting is developed. The model is calibrated with field data to obtain steady-state constants; transient predictions are compared to measured temperatures during cyclic misting for two different size birds. Measured temperatures during cyclic misting are shown to swing between steady-state asymptotes predicted from the model. Transient response of the model was faster than measured temperature data, in part due to temperature sensor dynamic response. The model predicts the length-wise temperature profile within the building during misting, and can be used to investigate alternate misting strategies and designs. …

Mechanical Backup Systems For Electronic Environmental Controllers, Richard S. Gates, Douglas G. Overhults, Larry W. Turner

Biosystems and Agricultural Engineering Faculty Publications

A series of mechanical backup systems for electronic environmental controllers is presented for a typical finishing swine barn and a typical tunnel ventilated broiler house. The systems consist of mechanical thermostats and timers used in parallel with the electronic controller, designed to ensure animal survival in the event of controller or related hardware failure. For swine housing, three distinct mechanical backup functions are identified; for broiler housing, four distinct mechanical backup functions are identified. Schematic diagrams of the mechanical backup functions are provided and their implementation is described.

A Survey Of Electronic Environmental Controllers, Richard S. Gates, Douglas G. Overhults, Larry W. Turner

Biosystems and Agricultural Engineering Faculty Publications

Sixteen commercially available electronic environmental controllers were evaluated. The units were classified according to enclosure type, analog versus microprocessor based control, power supply, sensors, alarms, control relays and triac output, interval timers, outside temperature feedback, and retail price. An assessment of these controllers indicated several critical limitations in the application of this technology.

The use of integrated controllers for animal production has the potential for substantial improvements in production efficiencies. If the limitations observed in the present controller technology, as represented by this sample, are addressed, industry acceptance of the technology can be accelerated. A uniform standard to address this …

Transient Overvoltage Testing Of Environmental Controllers, Richard S. Gates, Larry W. Turner, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

The integrated electronic control system will provide a new method for the day-to-day management of environmental control of animal production systems. No standards are currently accepted for transient overvoltage protection of these controllers. To assess the adequacy of existing designs, a test circuit was designed and used for a transient open circuit over-voltage waveform (ANSI/IEEE C62.41-1980) of 16 environmental control units: a maximum spike of 770 V was applied to the power supplies, and a spike up to 100 V was applied to temperature sensor lines. For these relatively mild tests, no failures were noted due to power supply transients, …

Non-Transposing Mute, Benjamin R. Gossick, Karl A. Schneider

Electrical and Computer Engineering Faculty Patents

A non-transposing mute having a metallic hemispherical resonator with a hollow acoustic filter attached thereto is provided for detachably fitting upon the rim of a brass musical instrument. A variety of tonal quality is available by choice of the particular filter selected by the musician.