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Full-Text Articles in Engineering

Linking Channel Stability And Bed Sediment Characteristics To Biological Integrity In Tennessee Ridge And Valley Streams, Kelley H. Williams Dec 2005

Linking Channel Stability And Bed Sediment Characteristics To Biological Integrity In Tennessee Ridge And Valley Streams, Kelley H. Williams

Masters Theses

Streambed sedimentation has plagued waterways since the beginning of civilization, whether as a natural flow process or human disturbances on the landscape in more recent times. Due to the continual degradation in the quantity and diversity of aquatic organisms within streams, the issue has finally surfaced as a significant concern. The need to develop better Total Maximum Daily Load (TMDL) assessment tools to link sediment impairment to biological integrity was the driving force behind this study.

Within the Ridge and Valley Ecoregion, 76 stream reaches were analyzed to investigate the impacts of stability issues and bed sediment characteristics on stream …


Automated Analysis Of Fluorescent Microscopic Images To Identify Protein-Protein Interactions, Sankar Venkataraman Dec 2005

Automated Analysis Of Fluorescent Microscopic Images To Identify Protein-Protein Interactions, Sankar Venkataraman

Masters Theses

The identification and confirmation of protein interactions significantly challenges the field of systems biology and related bio-computational efforts. The identification of protein-protein interactions along with their spatial and temporal localization is useful for assigning functional information to proteins. Fluorescence microscopy is an ideal method for assessing protein localization and interactions as a number of techniques and reagents have been described. Historically, data sets obtained from fluorescence microscopy have been analyzed manually, a process that is both time consuming and tedious. The development of an automated system that can measure the location and dynamics of interacting proteins inside a live cell …


Synthesis, Microstructure, And Mechanical Behavior Of Fe-Cu Composites, Jin-Woo Jeon Dec 2005

Synthesis, Microstructure, And Mechanical Behavior Of Fe-Cu Composites, Jin-Woo Jeon

Masters Theses

The synthesis, microstructure, and mechanical properties of ball-milled nanocrystalline (nc) Fe powder and immiscible Fe-Cu alloy composites are investigated in this thesis. Experimental approaches are described for the characterization of the grain size and hardness of nc Fe powders and the internal stress state of bulk Fe-Cu alloy composites are presented.

The grain size measurements of ball-milled Fe powders obtained from the XRD line broadening analysis (15 nm) and TEM observation (18 nm) showed good agreement between two results. From the nanoindentation tests, the hardness values of the ball-milled Fe powders were increased from 3.5 to 10.5 GPa as the …


A Dynamic Ampacity Model For The Testing Of Advanced Conductors, Matthew Benjamin Sooter Dec 2005

A Dynamic Ampacity Model For The Testing Of Advanced Conductors, Matthew Benjamin Sooter

Masters Theses

Advanced Conductors are an intriguing new technology that promises to help the utility industry increase the transmission capacity available in the United States. Manufacturers of advanced conductors promise double the current carrying capacity of normal Aluminum Clad Steel Reinforced conductor through a combination of increased thermal limits and decreased thermal elongation.

This thesis will outline a control developed for the Power Line Conductor Accelerated Test Facility at Oak Ridge National Laboratory. This custom facility is designed for the testing and rapid aging of advanced overhead conductors as part of a U.S. Department of Energy initiative to assist the development and …


Optimization Of Dsss Receivers Using Hardware-In-The-Loop Simulations, Balbir Kaur Dhillon Dec 2005

Optimization Of Dsss Receivers Using Hardware-In-The-Loop Simulations, Balbir Kaur Dhillon

Masters Theses

Over the years, there has been significant interest in defining a hardware abstraction layer to facilitate code reuse in software defined radio (SDR) applications. Designers are looking for a way to enable application software to specify a waveform, configure the platform, and control digital signal processing (DSP) functions in a hardware platform in a way that insulates it from the details of realization.

This thesis presents a tool-based methodolgy for developing and optimizing a Direct Sequence Spread Spectrum (DSSS) transceiver deployed in custom hardware like Field Programmble Gate Arrays (FPGAs). The system model consists of a tranmitter which employs a …


Topology Optimization Of Carbon Nanotube Reinforced Polymer Damping Structures, Seshadri Mohan Varma Damu Dec 2005

Topology Optimization Of Carbon Nanotube Reinforced Polymer Damping Structures, Seshadri Mohan Varma Damu

Masters Theses

Topology optimization has been successfully used for improving vibration damping in constrained layer damping structures. Reinforcing carbon nanotubes in a polymer matrix greatly influence the mechanical properties of the polymer. Such nanotube-reinforced polymers (NRP) can be used to further enhance the damping properties of the constrained layer structures. In this work, topology optimization is performed on constrained damping layer structures using NRP in order to maximize the loss factor for the first resonance frequency of the base beam. In addition to the material fractions of the NRP and elastic material, the volume fraction of the nanotubes in the polymer is …


Characterizing Turbulence Structure Along Woody Vegetated Banks In Incised Channels: Implications For Stream Restoration, Frank James Dworak Dec 2005

Characterizing Turbulence Structure Along Woody Vegetated Banks In Incised Channels: Implications For Stream Restoration, Frank James Dworak

Masters Theses

The impacts of urbanization have modified natural watersheds and stream hydraulic, hydrologic, and geomorphic processes that have lead to geomorphic and ecological disturbances in natural stream systems. These alterations have resulted in channel incision and the loss of channel-scale hydraulic characteristics responsible for initiating and maintaining pool-riffle bedforms, which are capable of supporting diverse biological stream ecosystems. Through the use of FLOW-3D, a 3-dimensional computational fluid dynamics model, three scenarios of an urban, incised, and channelized stream were simulated to characterize the turbulent, hydraulic structure during bankfull discharge. The simulations were conducted with trees inhibiting bankfull flow (representing the channel’s …


Comparison Of Microscopic Modalities For The 3d Model Reconstruction Of Nanodevices, Christopher Robert Kammerud Dec 2005

Comparison Of Microscopic Modalities For The 3d Model Reconstruction Of Nanodevices, Christopher Robert Kammerud

Masters Theses

As manufacturing capabilities push nanotechnology to smaller and smaller scales, novel inspection schemes must be developed to ensure product quality. The objective of our research was to implement, refine, and compare 3D reconstruction algorithms that could aid manufacturers in their ability to visualize and inspect nanodevices. Data was collected from three different microscopes: the atomic force microscope (AFM), the scanning electron microscope (SEM), and the laser scanning confocal microscope (LSCM). For each of these microscopes, a specific algorithm was implemented to generate 3D models from the raw microscope data. Scans from the AFM microscope give range information similar to laser …


A Statistical Based Model To Manage Perishable Goods Within A Cold Supply Chain, Amanda Rhiana Hicks Dec 2005

A Statistical Based Model To Manage Perishable Goods Within A Cold Supply Chain, Amanda Rhiana Hicks

Masters Theses

"Cold chain" management, the management of a temperature sensitive supply chain, has its own particular set of logistical challenges and issues when compared to a non-temperature sensitive supply chain. Current supply chain management techniques and tools that are utilized today in industry do not take this unique set of challenges into account. This thesis will focus on how using a model that has been built upon the theories of statistical process control techniques that does take the challenges into account, when monitoring and evaluating in-transit shipment of perishable goods throughout the cold supply chain, can assist in continuously improving the …


Viscosity Measurement Technique By Merging Liquid Drops Aboard The International Space Station, Daniel Aaron Lehman Dec 2005

Viscosity Measurement Technique By Merging Liquid Drops Aboard The International Space Station, Daniel Aaron Lehman

Masters Theses

The efforts reported in this thesis has been to analyze the data from two "Fluid Merging Viscosity Measurement" experiments in order to validate this as a viable method for measuring the viscosity of fluids with known surface tensions. This method involves simultaneously using a numerical analysis code and experimental data to produce matching curves of contact radius versus time and from that a determination of viscosity. Two experiments that were performed, used different liquids (glycerin and 125 Poise silicon oil) and different size ratios between the two drops ( 1 to 1 and O. 3 3 to 1 respectively). The …


A Study Of Material Properties And Relevant Microstructure Parameters That May Influence The V50 Ballistic Limit Velocity Of Composite Ceramics, Adolphus Mcdonald Dec 2005

A Study Of Material Properties And Relevant Microstructure Parameters That May Influence The V50 Ballistic Limit Velocity Of Composite Ceramics, Adolphus Mcdonald

Masters Theses

The purpose of this research is to evaluate, compare, and correlate the microstructure and mechanical properties of a selected group of ceramic armor samples to the V50 ballistic limit velocity. This study is to identify any relation between the desired material properties and the relevant microstructure parameters that significantly influence the ballistic limit velocity. The ceramic materials, silicon carbide and boron carbide, were produced and provided by five foreign companies. These companies were under contract by the United States Army, Research, Development, and Engineering Command to provide ceramic armor for comparative testing and material evaluation.

Ballistic testing was carried …


Experimental Aerodynamic Analysis Of A Wing-Flap System With Delta Vortex Generators, Charles Roy Mcconnell Dec 2005

Experimental Aerodynamic Analysis Of A Wing-Flap System With Delta Vortex Generators, Charles Roy Mcconnell

Masters Theses

The principle idea upon which the use of vortex generators (VGs) is based has been to control flow separation. The characteristic of VGs has been used to improve lift and alter the stall characteristics of aircraft and has been a relatively common practice for many years. Due to the seemingly limitless range of VG geometries and arrangements, which are largely dependant upon the desired aerodynamic performance, there has been a broad investigation into VG application.

The purpose of this experimental investigation has been to collect data to be used to establish the effects of various delta shaped vortex generators (delta-VGs) …


Universal Geometric Camera Calibration With Statistical Model Selection, Chistopher Paul Broaddus Dec 2005

Universal Geometric Camera Calibration With Statistical Model Selection, Chistopher Paul Broaddus

Masters Theses

We propose a new universal camera calibration approach that uses statistical information criteria for automatic camera model selection. It requires the camera to observe a planar pattern from different positions, and then closed-form estimates for the intrinsic and extrinsic parameters are computed followed by nonlinear optimization. In lieu of modeling radial distortion, the lens projection of the camera is modeled, and in addition we include decentering distortion. This approach is particularly advantageous for wide angle (fisheye) camera calibration because it often reduces the complexity of the model compared to modeling radial distortion. We then apply statistical information criteria to automatically …


Physical Layer Simulation Study For The Co-Existence Of Wlan Standards, Chad Joseph Kiger Dec 2005

Physical Layer Simulation Study For The Co-Existence Of Wlan Standards, Chad Joseph Kiger

Masters Theses

Interference is a prime factor that limits the performance of devices within the 2.4 GHz ISM Band. Due to the ISM Band being unlicensed and free to all users, there is an abundance of devices within this frequency range. The three most prominent of such devices used for data communication consist of Bluetooth, Wifi, and Zigbee. In order to understand whether these three protocols can co-exist with each other, a physical layer system model will be developed for each protocol. These systems models will be combined and their interaction with each other examined to determine the effects of the interference …


Comparing Material Impact Strength Of Three High Impact Plastic Resins Used In Automotive Grille Using Nonlinear Finite Element Analysis Tools, Jason Santiago Aug 2005

Comparing Material Impact Strength Of Three High Impact Plastic Resins Used In Automotive Grille Using Nonlinear Finite Element Analysis Tools, Jason Santiago

Masters Theses

As a part of Team Value Management program, existing products are benchmarked against the best in class products and their product design and manufacturing reviewed to identify ways to lower costs, such as using less expensive materials or streamlining manufacturing processes.

In this study an effort has been made to compare impact properties of three different plastic resins used in car grilles. The plastic resins being compared are a proprietary grade PC+ABS, an alternate commercial grade PC +ABS and a commercial grade ABS. The results from this study will be used to evaluate the feasibility of replacing PC+ABS with ABS …


Design Of A Reconfigurable State Transition Algorithm For Fuzzy Automata, Paolo A. Tamayo Aug 2005

Design Of A Reconfigurable State Transition Algorithm For Fuzzy Automata, Paolo A. Tamayo

Masters Theses

An Ontological Controller, a type of supervisory controller used for complex industrial systems, is usually characterized by a large global state set. Monitoring the global state set of these systems is impractical when the desired goal path is chosen since the decision on the next state depends only on a small section of the total state space. The approach is to operate only in a small moving window of the large state transition path. The Hybrid Fuzzy-Boolean Finite State Machine (HFB-FSM) is part of the solution to implement this scheme. The HFB-FSM models the state graph along with plant data …


Electron Beam Cured Resins For Wood Composites, Ting Song Aug 2005

Electron Beam Cured Resins For Wood Composites, Ting Song

Masters Theses

Adoption of rapid, low temperature electron beam curable resin systems provide a great potential for energy saving to the wood composites industry. Other considerable advantages benefit from the radiation progression including: cost saving, reduction curing time, increased throughout capacity, minimal volatile emissions, increased the design flexibility.

The research was mainly focused on radiation dose optimization, resin structure-property relationships investigation, and resin-wood bonds evaluation. Resin chemical, physical, and mechanical properties were explored in detail by means of various testing methods. The formulating studies were concentrated on the radiation curable monomers (polyfunctional and monofunctional) and their effects to the network performance. Mechanical …


Reverse-Flow Oxidation Catalyst With Supplemental Fuel Injection For Lean-Burn Natural Gas Engines, Steven Scott Smith Aug 2005

Reverse-Flow Oxidation Catalyst With Supplemental Fuel Injection For Lean-Burn Natural Gas Engines, Steven Scott Smith

Masters Theses

The purpose of this research is to demonstrate that the use of a reverse-flow oxidation catalyst reactor (RFOCR), both with and without supplemental fuel injection (SFI), will result in significant reductions of methane (CH4) in a simulated lean-burn natural gas exhaust mixture. Methane reduction is investigated as a function of the directional duration of the exhaust gases through the oxidation catalyst, gas hourly space velocity (GHSV), and exhaust gas temperature. The CH4 catalytic chemical reaction, at an elevated exhaust gas temperature, is an exothermic reaction and elevating the temperature across the catalyst reactor corresponds to an increase in CH4 conversion. …


Human Factors Evaluation Of Portable Electronic Devices In Tactical Aircraft, Martin Bernard Fuerst Aug 2005

Human Factors Evaluation Of Portable Electronic Devices In Tactical Aircraft, Martin Bernard Fuerst

Masters Theses

As the service life of aging military aircraft are extended and these aircraft are tasked with new missions they were never designed to support, military aircraft are constantly being upgraded with new systems and avionics. Additionally, many legacy aircraft have poor cockpit layouts or incorporate older displays that are not compatible with or require extensive modification to support these new technologies. Unfortunately, many acquisition programs do not have the luxury of an unlimited budget and schedule to complete the required upgrades. One alternative is to incorporate a portable electronic device or PED into the cockpit. These devices can provide moving …


Alkali Silica Reaction In Virgin And Recycles Aggregates: State Of The Art And Experimental Investigation Using Astm C 1260 And The Staining Method, Shadi Sami Bajjali Aug 2005

Alkali Silica Reaction In Virgin And Recycles Aggregates: State Of The Art And Experimental Investigation Using Astm C 1260 And The Staining Method, Shadi Sami Bajjali

Masters Theses

Alkali silica reaction (ASR) is one of the most prevalent causes of concrete deterioration worldwide. A study done in 1995 showing the impact of ASR on structures stated that 104 concrete dams and spillways, massive concrete structures, have been damaged by alkali silica reaction up to date. Since its discovery by Stanton (1940), there has been significant research on ASR, and major advances have been made in understanding the mechanism underlying ASR-induced expansion and in developing methods of preventing ASR in new and existing concrete through proper measures including proper materials selection and mixture proportioning.

This thesis summarizes the findings …


“Modeling Study Of Individual And Group Behavior Of Brazilian Free-Tailed Bats (Tadarida Brasiliensis) And Dynamic Bat Counting Using Real-Time Infrared Thermal Video, Aruna Raghavan Aug 2005

“Modeling Study Of Individual And Group Behavior Of Brazilian Free-Tailed Bats (Tadarida Brasiliensis) And Dynamic Bat Counting Using Real-Time Infrared Thermal Video, Aruna Raghavan

Masters Theses

Brazilian free-tailed bats live as colonies in caves, under bridges and in places where human exploitation is perceived to be minimal. These bats emerge out of their habitats to forage in the fields nearby and help in natural pest control. These bats consume thousands of tons of insects every day in quantities that can amount to 2/3 of the body weight of each bat. The life of these natural pest destroyers are under threat due to human ignorance, exploitation and unknown myths.

For economic reasons, it becomes necessary to study the behavior and movement of these bats and to count …


Microstructural Evolution Of Tial-Intermetallic Alloys Containing W And B, Lan Huang Aug 2005

Microstructural Evolution Of Tial-Intermetallic Alloys Containing W And B, Lan Huang

Masters Theses

The TiAl alloys have been considered as promising candidates for structural-materials applications at around 8000C. In this work, new TiAl alloys, containing tungsten (W) and boron (B), have been developed. Using the scanning-electron microscopy (SEM), electron-microprobe, and transmission-electron microscopy (TEM), the effects of W and B on the microstructural evolution of TiAl alloys, including the colony size and lamellar spacing, were analyzed. It is important to point out that fine uniform microstructures (with the colony size smaller than 50 mm) can be conveniently developed after Hot-Isostatic Pressing (HIP) the as-cast alloys at 1,2500C and 150 MPa …


Clinical Significance Of Hip Separation In Metal On Polyethylene, Metal On Metal, And Ceramic On Ceramic Tha Due To Resonant And Energy Dispersion Effects, Joseph Scott Bader Aug 2005

Clinical Significance Of Hip Separation In Metal On Polyethylene, Metal On Metal, And Ceramic On Ceramic Tha Due To Resonant And Energy Dispersion Effects, Joseph Scott Bader

Masters Theses

Femoral head sliding within the acetabular cup does occur in THA. Since it is
known that impact conditions can lead to component ringing, the present study
investigates the vibrational response of variable bearing surface materials. A further understanding of the physical response resulting from impact during femoral head sliding may lead to valuable insight pertaining to THA failure.
Accelerometers were mounted to synthetic bones which had been implanted with hip prostheses. Data was collected from these sensors as a machine impacted the femoral head into the acetabular cup. These tests were carried out for metal-metal, ceramicceramic, and metal-polyethylene bearing surfaces …


A 2.4 Ghz Lc-Vco Using On-Chip Inductors And Accumulation-Mode Varactors In A Cmos 0.18 Μm Process, Bryant Derand Williamson Aug 2005

A 2.4 Ghz Lc-Vco Using On-Chip Inductors And Accumulation-Mode Varactors In A Cmos 0.18 Μm Process, Bryant Derand Williamson

Masters Theses

The demand for low power, low cost, and low noise RF sub-systems has lead to the development of completely integrated transceivers. Frequency synthesizers containing a PLL and a crystal oscillator are perhaps the most challenging part of a transceiver’s design. One of its nosiest, most power consuming components, the VCO, often makes the PLL a challenging design. For an LC-VCO, the best type of VCO for quality noise performance, the struggle lies in the fully integrated inductor. Despite the vast improvement in additional facets of the LC-VCO, the integrated inductor lags in its accomplishments; and the focus of designers is …


Inverse Problems In Image Processing: Blind Image Restoration, Ravi Viswanathan Aug 2005

Inverse Problems In Image Processing: Blind Image Restoration, Ravi Viswanathan

Masters Theses

Blind Image Restoration pertains to the estimation of degradation in an image, without any prior knowledge of the degradation system, and using this estimation to help restore the original image. Original Image, in this case, refers to that version of the image before it experienced degradation. In this thesis, after estimating the degradation system in the form of Gaussian blur and noise, we employ Deconvolution to help restore the original image.

In this thesis, we use a Redundant Wavelet based technique to estimate blur in the image using high-frequency information in the image itself. Lipschitz exponent – a measure of …


Mechanical Design And Integration Of A Tracking Fluoroscope System, Robert Bradley Cunningham Aug 2005

Mechanical Design And Integration Of A Tracking Fluoroscope System, Robert Bradley Cunningham

Masters Theses

The Tracking Fluoroscope System (TFS) – patent pending serial number 60/606,480 – is a robotic platform designed to follow a patient's natural, uninhibited walking motion and obtain full-range-of-motion x-ray videos of a patient's ankle, knee, or hip. The video data can be used to analyze dynamics within the human body and develop mathematical models of the joints. The TFS can also be used to study artificial implants under various conditions in order to design more effective versions. Similar systems could be used to aid surgeons in artificial implant procedures. Athletic motions could be analyzed to design more effective sports equipment …


Design And Development Of Epics Based Rf Conditioning System For The High Power Rf Components Of Charged Particle Accelerators, S.M. Shajedul Hasan Aug 2005

Design And Development Of Epics Based Rf Conditioning System For The High Power Rf Components Of Charged Particle Accelerators, S.M. Shajedul Hasan

Masters Theses

Charged particle accelerators use various vacuum windows on their accelerating RF cavities to pass very high RF power through for the acceleration of particles. The accelerating cavities and the windows should be cleaned, baked and fully RF conditioned to eliminate poor vacuum caused by outgassing and other contamination. The linear accelerator (Linac) in the Spallation Neutron Source (SNS) contains various accelerating cavity structures and RF conditioning of their high power vacuum windows is necessary for present work as well as future upgrade and development. An example is the coaxial fundamental power coupler (FPC) with an annular alumina ceramic window for …


Design And Analysis Of New Concept Interior Permanent Magnet Synchronous Motor By 3d Finite Element Analysis, Seongtaek Lee Aug 2005

Design And Analysis Of New Concept Interior Permanent Magnet Synchronous Motor By 3d Finite Element Analysis, Seongtaek Lee

Masters Theses

Throughout the years Hybrid Electric Vehicles (HEV) require an electric motor which has high power density and wide constant power operating region as well as low manufacturing cost. For these purposes, a new concept permanent magnet motor is designed and analyzed with the basic theories about Interior Permanent Magnet Synchronous Motor (IPMSM).

This new motor has DC excitation coils and flux paths, which can increase the output torque and be controlled for field weakening operating. The analysis has been conducted by three-dimensional Finite Element Analysis. The results show the possibility of the new motor for HEV applications. The new motor …


Civilian Target Recognition Using Hierarchical Fusion, Balasubramanian Lakshminarayanan Aug 2005

Civilian Target Recognition Using Hierarchical Fusion, Balasubramanian Lakshminarayanan

Masters Theses

The growth of computer vision technology has been marked by attempts to imitate human behavior to impart robustness and confidence to the decision making process of automated systems. Examples of disciplines in computer vision that have been targets of such efforts are Automatic Target Recognition (ATR) and fusion. ATR is the process of aided or unaided target detection and recognition using data from different sensors. Usually, it is synonymous with its military application of recognizing battlefield targets using imaging sensors. Fusion is the process of integrating information from different sources at the data or decision levels so as to provide …


An Investigation Of The Rotor Tip Path Height Of The Mh-60s Helicopter In View Of Forklift Clearance In Support Of The United States Navy Medium Lift Shipboard Logistics Mission, Jonathan Patrick Kline Aug 2005

An Investigation Of The Rotor Tip Path Height Of The Mh-60s Helicopter In View Of Forklift Clearance In Support Of The United States Navy Medium Lift Shipboard Logistics Mission, Jonathan Patrick Kline

Masters Theses

The purpose of this paper is to summarize Department of the Navy tests performed to measure rotor tip path height of the MH-60S helicopter and present an analysis of collected data to determine if safe cargo loading operations on the MH-60S can be conducted with a forklift while the rotor is engaged. Testing was conducted to measure the dynamic height of the rotor tip path plane during incremental cyclic displacements, rotor response to external disturbances, and pilot tendencies when centering the cyclic control stick. Additional information was gathered on representative forklifts in use on U.S. Navy ships, and shipboard operating …