Engineering Commons^™

Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi

Electronic Theses and Dissertations

Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of σ3' are small (10-81 …

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism …

Fatigue Of Older Bridges In Northern Indiana Due To Overweight And Oversized Loads, Volume 1: Bridge And Weigh-In-Motion Measurements, James A. Reisert, Mark D. Bowman

JTRP Technical Reports

This report is the first of a two-volume final report presenting the findings of the research work that was undertaken to evaluate the fatigue behavior of steel highway bridges on the extra heavy weight truck corridor in Northwest Indiana. The purpose of the study was to evaluate the type and magnitude of the loads that travel along the corridor and then assess the effect of those loads on the fatigue strength of the steel bridge structures on the corridor. This volume presents the results of the experimental field study conducted to evaluate the load and load effects on one steel …

Hma Pavement Performance And Durability, Eliana Del Pilar Vivar, John E. Haddock

JTRP Technical Reports

It has long been argued that at densities higher than approximately 92 percent (air void contents lower than 8 percent), a hotmix asphalt mixture is impermeable to water. However, as densities become lower (air void contents higher) than this, small decreases in the density can yield exponential increases in permeability. The objectives of this study were to better understand the increases in hot-mix asphalt pavement performance and durability that can be gained by increasing the initial pavement density and to better quantify the inter-relationship among pavement density, permeability, and moisture-induced damage. The long-term performance and durability of four hot-mix asphalt …

Flood Frequency Relationships For Indiana, A. Ramachandra Rao

JTRP Technical Reports

The objective of the research presented in this report is the development of relationships to estimate flood magnitudes for Indiana streams. In order to achieve this goal several probability distributions were evaluated. The Pearson (3) (LP(3)) and the Generalized Extreme Value (GEV) distributions were found to be the best distributions for Indiana data. Because of the requirement that Log Pearson (3) (LP(3)) distribution must be used in federally-funded projects it was retained in the study.

Relationships were developed for the flood frequencies to be estimated by the LP(3) distributions. The State of Indiana has been divided into regions, seven of …

Vendor Comparison Of Video Detection Systems, Avery Rhodes, Edward J. Smaglik, Darcy M. Bullock

JTRP Technical Reports

Video detection has become increasingly popular for presence detection at signalized intersections because of its versatility. However, several reports have documented performance problems in specific systems. This paper quantifies the performance of three different commercially available video detection systems. The systems were tested in May and September 2005 for presence detection accuracy. Prior to the May 2005 test, a representative from each vendor configured the video detection zones to match the loop detection zone as closely as possible. The outputs from the loop detection for the through-right and left-turn lane groups were compared with the corresponding output from each of …

Ramp Metering And High Occupancy Vehicle Facilities: A Synthesis Study, Abhishek Bhargava, Euridice A. Oware, Samuel Labi, Kumares C. Sinha

JTRP Technical Reports

High Occupancy Vehicle (HOV) lanes and ramp metering have been implemented at several places in the country to improve traffic conditions on freeways. This report presents a comprehensive study of the state of the art and state of the practice of these facilities in the U.S. and their effectiveness in improving traffic conditions on the freeway. The various types of HOV facilities have been discussed along with other system components such as park-and-ride facilities, ridership programs, enforcement areas and policies, ingress/egress facilities. The cost of several HOV facilities in the country has been presented and a set of guidelines have …

Advanced Compaction Quality Control, Carlos Zambrano, Vincent P. Drnevich, Philippe L. Bourdeau

JTRP Technical Reports

This Synthesis Study gathered the current knowledge on the topic of Intelligent Compaction and provides INDOT with recommendations for action. It appears that totally embracing this technology at this time is premature. On the other hand, it also appears that prudent use of this technology could provide tremendous benefit-to-cost ratios over the long term and position Indiana as a leader among the States in adopting it. After examining the technological developments over the last decade it is concluded that Intelligent Compaction is a near certainty in the future. The big question is: When is the right time to begin working …

Primary Emergency Routes For Transportation Security, Srinivas Peeta, Georgios Kalafatas

JTRP Technical Reports

Security threats and natural disasters (such as hurricanes and cyclones) are events that have historically led to large scale evacuations. Evacuation operations are strongly characterized by traffic volumes that substantially exceed the network capacity, and consequently, the potential for severely degraded network performance. The efficient management of evacuations entails long-term planning and real-time operational paradigms that are, ideally, integrated. This study focuses primarily on the planning aspects of evacuation, while providing important insights for operations. Identifying capacity as a key element to efficient evacuation, the evacuation planning seeks to determine links where additional capacity is desired, as well as the …

Muskegon Wastewater Land Treatment System: Fate And Transport Of Phosphorus In Soils And Life Expectancy Of The System, C. Hu, Tian Zhang, Y. H. Huang, Mohamed F. Dahab, D. Kendrick, R. Surampalli

Department of Civil and Environmental Engineering: Faculty Publications

The build-up of phosphorus (P) in soil is a major factor limiting the operating life of a wastewater land treatment system. In this study, effects of long-term wastewater application on changes in chemical properties, P profiles, and P adsorption capacity were evaluated in soils of the Muskegon wastewater land treatment plant that has been treating wastewater for > 30 years. Results indicate that the major soil properties have been changed. In the 15 cm topsoil, the pH increased from &#;&#;5–6 in 1973 to &#;&#;7.4–7.8 in 2003; the soil’s total organic carbon (TOC) increased by 10–71 %; and the level of exchangeable …

Interview No. 1656, Robert W. Pitt

Combined Interviews

Robert Pitt was born in Detroit, MI on November 20, 1933; his family relocated a lot, he first remembers living in Portland, OR, later moved to Phoenix, AZ where he remembers the bombing of Pearl Harbor and followed the progress of World War II at home; he recounts moving to Los Angeles, CA for a year, his time as a batboy for the Los Angeles Angels and his love of baseball; he moved again to Chicago, IL to attend Morgan Park Military Academy, his father died when he was fifteen. Mr. Pitt describes time at Northwestern University in Evanston, IL …

Ecue: A Spam Filter That Uses Machine Learning To Track Concept Drift, Sarah Jane Delany, Padraig Cunningham, Barry Smyth

Conference papers

While text classification has been identified for some time as a promising application area for Artificial Intelligence, so far few deployed applications have been described. In this paper we present a spam filtering system that uses example-based machine learning techniques to train a classifier from examples of spam and legitimate email. This approach has the advantage that it can personalise to the specifics of the user’s filtering preferences. This classifier can also automatically adjust over time to account for the changing nature of spam (and indeed changes in the profile of legitimate email). A significant software engineering challenge in developing …

Learning Traditional Irish Music Using A Pda, Bryan Duggan

Conference papers

A common problem experienced by musicians in traditional music sessions is that of recalling tunes on demand from a large repertoire. Traditional music is largely an oral medium and musicians may recall a name or player of a tune or set, but require hearing the first few notes to start the tune. In this paper, we present our work developing TunePal, a tool that can be used by musicians for the storage and retrieval of traditional music melodies for learning purposes. TunePal is specifically desiged to be used by musicians playing Irish traditional music in sessions as it supports the …

Employee Commitment And Turnover: Literature And Data Analysis Of Correlations, Jean-Paul M. Arnaout, Gamze Karayaz, Andres Sousa-Poza

Engineering Management & Systems Engineering Faculty Publications

Due to the current turbulent environment, companies had to evolve form their traditional rigid structures to flexible and efficient ones, in order to better adapt to the continuous changes in the environment. New practices have emerged in the workplace, particularly the large layoffs of employees due to budget cuts, leading to an increase in the organizations' turnover. Thus, in today's world, a company is subject to high turnovers at any time of its life cycle; a suggested approach for reducing this turnover is through the improvement of organizational commitment. This paper addresses the following question: "Do all forms of employee …

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 …

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Building Services Engineering

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Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek

Physics Faculty Publications and Presentations

The crystallographic phase and morphology of many materials change with the crystal size so that new needs arise to determine the crystallography of nanocrystals. Direct space high-resolution phase-contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) when combined with tools for image-based nanocrystallography in two (2D) and three (3D) dimensions possess the capacity to meet these needs. After a concise discussion of lattice-fringe visibility spheres and maps, this paper discusses lattice-fringe fingerprinting in 2D and tilt protocol applications. On-line database developments at Portland State University (PSU) that support image-based nanocrystallography are also mentioned.

Lattice Fringe Fingerprinting In Two Dimensions With Database Support, Peter Moeck, B. Seipel, R. Bjorge, P. Fraundorf

Physics Faculty Publications and Presentations

A brief introduction to lattice fringe fingerprinting in two dimensions (2D) with database support is given. The method is employed for the identification of the crystal phase of a small ensemble of nanocrystals. The enhanced viability of this method in aberration-corrected transmission electron microscopes (TEMs) and scanning TEMs (STEMs) is also illustrated.

Designing Computer Agents With Facial Personality To Improve Human-Machine Collaboration, Brian Esley Tidball

Browse all Theses and Dissertations

The development of computer agents to enhance human-computer interfaces is an evolving field of study. This study examined whether people perceive personality in static digital faces that portray expressions of emotion, and if the digital faces would influence human performance on a simple human-machine collaborative task. The first experiment measured user-perception of personality, based on the emotional expression in two sets of five static digital faces. The results from this first phase revealed that participants provided different ratings, of the Big-Five personality model sub-traits, based on the emotional expression of a static digital face. This indicates a perception of personality …

Digital Channelized Wide Band Receiver Implemented With A Systolic Array Of Multi-Rate Fir Filters, David M. Rodney

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This thesis proposes the use of a Systolic Array of Multi-Rate FIR Filters to improve performance by eliminating the requirement of the FFT and De-Multiplexer associated with the conventional receiver while achieving the same functionality. The FFT is a major bottle neck for improving system performance for the conventional DCWBR because many complex multiplications and additions are required. The proposed new architecture is designed and evaluated in MATLAB to illustrate its viability. Two approaches for improved channel arbitration are accessed in MATLAB, namely, channel bin’s rms comparison and parallelism of the Systolic Array Multi-Rate FIR Filters. The FIR filters (high-pass …

Fpga Frequency Domain Based Gps Coarse Acquisition Processor Using Fft, Cyprian D. Sajabi

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The Global Positioning System or GPS is a satellite based technology that has gained widespread use worldwide in civilian and military applications. Direct Sequence Spread spectrum (DSSS) is the method whereby the data transmitted by the satellite and received by user is kept secure, low power and relatively noise-immune. The first step required in the GPS operation is to perform a lock on the incoming signal, both with respect to time synchronization and frequency resolution. Because of the need for reduced time to lock and also reduced hardware, algorithms based in the frequency domain have been developed. These algorithms take …

Flexible Sigma Delta Time-Interleaved Bandpass Analog-To-Digital Converter, Ryan Edward Mcginnis

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Conversion of analog signals to their digital equivalent earlier in a circuit’s topology facilitates faster and more efficient exploitation of the information contained within. Analog-to-digital converters (ADCs) form the link between the analog and digital realms. In high frequency circuits ADCs must often be implemented further downstream after several stages of down-conversion, or through the use of more expensive technologies such as Bi-polar Junction Transistors or Gallium Arsenide. This thesis presents a technique to utilize Complimentary Metal Oxide Semiconductor technology in a parallel time-interleaved architecture. This will reduce circuit complexity and allow the ADC to be placed further upstream reducing …

Design And Evaluation Of A Discrete Wavelet Transform Based Multi-Signal Receiver, Tony Chiang

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General purpose receivers of today are designed with a broad bandwidth so that the receiver can accept a wide range of signal frequencies. These receivers usually accept one signal along with any interference that is included. To increase the signal detection capabilities of the wideband receiver, a design for a receiver that can detect two signals is needed. One of the requirements for this receiver is that the second weak signal needs to be processed in a timely manner so that the receiver can recognize it. To remedy the problem, a module was developed using wavelet-based techniques to remove spurs …

Dissipated Energy At A Bimaterial Crack Tip Under Cyclic Loading, Jeremy S. Daily

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A new theory of fatigue crack growth in ductile solids has recently been proposed based on the total plastic energy dissipation per cycle ahead of the crack. This, and previous energy-based approaches in the literature, suggest that the total plastic dissipation per cycle can be closely correlated with fatigue crack growth rates under mode I loading. The goal of the current research is to extend the dissipated energy approach to steady-state crack growth under mixed-mode I/II loading conditions, with application to cyclic delamination of ductile bimaterial interfaces. Such systems can occur in brazing, soldering, welding, and a variety of layered …

Human-Centered Time-Pressured Decision Making In Dynamic Complex Systems, Subhashini Ganapathy

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Many real-world applications are complex, dynamic, and uncertain. Human operators play an important role in ensuring the safety and in achieving operational effectiveness in such systems. During task performance, both humans and computerized processes bring in varying strengths and limitations. Research on human-centered automation in aviation, satellite ground control, and nuclear power plant control has resulted in broad guidelines on system design involving human and computerized processes in supervisory control. However, problems such as increased human error, lack of situational awareness, and opacity from poorly automated systems remain, particularly in scenarios where human operators must make decisions in time-pressured planning. …

Cognitively-Engineered Multisensor Data Fusion Systems For Military Applications, Amanda Christine Muller

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The fusion of imagery from multiple sensors is a field of research that has been gaining prominence in the scientific community in recent years. The technical aspects of combining multisensory information have been and are currently being studied extensively. However, the cognitive aspects of multisensor data fusion have not received so much attention. Prior research in the field of cognitive engineering has shown that the cognitive aspects of any human-machine system should be taken into consideration in order to achieve systems that are both safe and useful. The goal of this research was to model how humans interpret multisensory data, …

Implementation Of A Multi-Layered Fuzzy Controller On An Fpga, Ajit Paal Singh Khatra

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The uses of Autonomous Mobile robots range from the teleoperated Sojourner on the Mars Pathfinder mission to cleaning robots in the Paris Metro. They have overtaken tasks which are too difficult or dangerous to perform or require the repetition of the same procedure over and over again and can become dull for a human to perform. The objective of this thesis is to develop and implement a multilayered fuzzy controller on an FPGA for the navigational control of an autonomous mobile robot (AMR). The navigational algorithm assists the robot in navigating through complex environments of passages and hallways. The FPGA …

Fabrication Of Oxide Superconducting Thin Films Using Colloid Of Nanoparticles As Precursor, Vamsee K. Chintamaneni

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This thesis reports the development of a new approach for the fabrication of superconducting thin films. Among the liquid phase methods of fabricating high temperature superconductors having critical current density about 1 MA/cm², metalorganic deposition using metal trifluoroacetates (TFA-MOD) is the best known method. In this project, detailed spectroscopic and microscopic analysis was performed at every stage of the TFA-MOD process to understand the evolution of crystalline superconducting film. It was observed that the TFA-MOD has some inherent disadvantages such as long process time, evolution of HF gas and results porosity in films. A new liquid phase process …

Direct Digital Frequency Synthesizer Implementation Using A High Speed Rom Alternative In Ibm 0.13u Technology, Matthew R. Gerald

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The direct digital synthesizer is a method of signal generation with many benefits. DDS designs are able to switch frequencies very quickly and also tune precisely to many different frequencies with the use of a constant operating frequency. There is a need for a low power, high speed DDS in the form an ASIC design. One major bottleneck in common DDS systems is the slow access time of a ROM. There is also a need for a high speed ROM alternative. This thesis delivers a high speed ASIC Direct Digital Synthesizer which operates at a 1 GHz operating frequency. This …

A Comparison Of Agent-Based Optimization Approaches Applied To The Weapons To Targets Assignment Planning Problem, Hitesh Deepak Soneji

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Real-world complex optimization problems are difficult to solve. Agent-based optimization approaches have proved useful in solving a wide variety of problems including optimization problems. Agent-based techniques can be used in military planning for solving allocation problems such as the weapons to targets assignment problem. Classical methods like linear programming (LP) have been used for solving weapons to targets assignment problems. LP approaches provide optimal solutions quickly, but in real-time planning when there are minor changes to input, LP exhibits widely varied solutions. This can be a problem in practice. This research study considers two agent-based optimization approaches, the Stable Marriage …