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2011

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Articles 4141 - 4170 of 5801

Full-Text Articles in Engineering

Use Of Bio-Ethanol And Bio-Diesel The Key Solution For A More Sustainable Road Transport, Alberto Boretti Jan 2011

Use Of Bio-Ethanol And Bio-Diesel The Key Solution For A More Sustainable Road Transport, Alberto Boretti

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Life Cycle Analysis (LCA) of alternative transportation fuels clearly shows the advantages of reducing the use of nonrenewable fossil fuels vs. renewable biologic novel fuels to reduce the emissions of carbon dioxide. Being based on the natural recycle of carbon dioxide through the use of renewable energy sources, use of these renewable fuels does not imply depletion of natural resources and is therefore sustainable in the long term. Renewable fuels and advanced internal combustion engines and powertrains are the technologies that in addition to be the most likely to produce benefits in term of carbon balance and fossil fuel saving, …


Robust Integral Of Neural Network And Sign Of Tracking Error Control Of Uncertain Nonlinear Affine Systems Using State And Output Feedback, Qinmin Yang, Sarangapani Jagannathan, Youxian Sun Jan 2011

Robust Integral Of Neural Network And Sign Of Tracking Error Control Of Uncertain Nonlinear Affine Systems Using State And Output Feedback, Qinmin Yang, Sarangapani Jagannathan, Youxian Sun

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel state and output feedback control law for the tracking control of a class of multi-input-multi-output (MIMO) continuous time nonlinear systems with unknown dynamics and disturbance input. First the state feedback-based control law is designed which consists of the robust integral of a neural network (NN) output plus the sign of the tracking error signal multiplied with an adaptive gain. the two-layer NN learns the system dynamics in an online manner while the NN residual reconstruction errors and the bounded system disturbances are overcome by the error sign signal. Both of the NN output and error …


High-Strength Selfconsolidating Concrete Girders Subjected To Elevated Compressive Fiber Stresses, Part 2: Structural Behavior, Jared E. Brewe, John J. Myers Jan 2011

High-Strength Selfconsolidating Concrete Girders Subjected To Elevated Compressive Fiber Stresses, Part 2: Structural Behavior, Jared E. Brewe, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The design of prestressed concrete members is restricted by the requirement that the extreme compressive fiber stress at midspan be less than 60% of the concrete compressive strength at release of prestressing. the purported purpose of this limit is to provide serviceability performance, but it places unnecessary limits on the capability of the materials. for this research program, six prestressed concrete girders were produced with high-strength, self-consolidating concrete and subjected to elevated compressive fiber stress levels ranging from 65% to 84% of initial concrete compressive strength at release of prestressing. Part 1 of this series analyzed time-dependent prestress losses and …


Lv-11-C031: Measured Levels Of Hospital Noise Before, During, And After Renovation Of A Hospital Wing, And A Survey Of Resulting Patient Perception, Cassandra H. Wiese, Lily M. Wang Jan 2011

Lv-11-C031: Measured Levels Of Hospital Noise Before, During, And After Renovation Of A Hospital Wing, And A Survey Of Resulting Patient Perception, Cassandra H. Wiese, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Acoustic conditions in hospitals can negatively influence a patient’s physical and psychological health. This paperreports on noise levels measured before, during, and after renovation of a hospital wing in an Omaha, Nebraska, facility thatregularly receives unsatisfactory noise scores on patient satisfaction surveys. Sound pressure levels were logged every 10seconds over four-day periods in three different locations: at the nurses' station, in the hallway, and in a nearby patient’sroom. The resulting data have been analyzed in terms of A-weighted equivalent sound levels (LAeq) as well as variousexceedance levels (Ln). Results indicate that sound levels did not change much due to the …


Industry-Experienced Graduate Student Program: Innovative Collaboration In Architectural Engineering At The University Of Nebraska–Lincoln, Clarence E. Waters, Steve Alvine, Michelle L. Eble-Hankins Jan 2011

Industry-Experienced Graduate Student Program: Innovative Collaboration In Architectural Engineering At The University Of Nebraska–Lincoln, Clarence E. Waters, Steve Alvine, Michelle L. Eble-Hankins

Durham School of Architectural Engineering and Construction: Faculty Publications

In 2001, the Architectural Engineering Department at the University of Nebraska–Lincoln, along with industry partners, established an industry-experienced graduate student program. The program was developed to bring experienced design professionals to collaborate with the industry while pursuing a Ph.D. in architectural engineering. This program is designed to be mutually beneficial to industry partners, -graduate students, the University of Nebraska–Lincoln Architectural Engineering Department, and the building industry at large. The first doctoral candidate in the program graduated, and significant collaborative work was completed for the industry partner. All parties to this initial offering are pleased with the outcome and believe the …


Catalytic Process For The Conversion Of Synthesis Gas To Ethanol For Use As An Alternative Fuel, Nitin Kumar Jan 2011

Catalytic Process For The Conversion Of Synthesis Gas To Ethanol For Use As An Alternative Fuel, Nitin Kumar

LSU Doctoral Dissertations

Higher alcohols are increasing as a proportion of the transportation fuel market, and can be used as neat fuels, or as blends with conventional fuels. For a number of reasons, these C2+-alcohols will be of interest in the foreseeable future. Large-scale production of higher alcohols will likely be carried out via syngas, which can be produced from a number of feedstocks, including coal, natural gas and biomass. Rhodium-based catalysts have been found to be the most active/selective for higher alcohols. However, the literature shows that the yields of C2+-alcohols that can be achieved with current catalysts, even the most active/selective, …


Surface Functionalization Of Crystalline Silicon Substrates, Sri Sai Vegunta Jan 2011

Surface Functionalization Of Crystalline Silicon Substrates, Sri Sai Vegunta

LSU Doctoral Dissertations

In this work, various chemical and electrochemical methods were demonstrated to attach application-specific organic monolayers to crystalline silicon substrates. In one study, alkyl monolayers were anodically electrografted or thermally grafted onto planar (100) silicon substrates using Grignard precursors. The results show electrografted methyl monolayers provide a stable Si-C termination, resisting oxidation on (100) surfaces for approximately 55 days in air. The alkyl termination could provide a potential alternative to defective native oxides and kinetically unstable hydride surfaces. A mechanism involving two electron transfers per grafting event was established for both the thermal and electrochemical routes. In another study, unsaturated organic …


Efficient And Robust Signal Detection Algorithms For The Communication Applications, Lu Lu Jan 2011

Efficient And Robust Signal Detection Algorithms For The Communication Applications, Lu Lu

LSU Doctoral Dissertations

Signal detection and estimation has been prevalent in signal processing and communications for many years. The relevant studies deal with the processing of information-bearing signals for the purpose of information extraction. Nevertheless, new robust and efficient signal detection and estimation techniques are still in demand since there emerge more and more practical applications which rely on them. In this dissertation work, we proposed several novel signal detection schemes for wireless communications applications, such as source localization algorithm, spectrum sensing method, and normality test. The associated theories and practice in robustness, computational complexity, and overall system performance evaluation are also provided.


Technology Management Trends In Law Schools, Carol A. Watson, Larry Reeves Jan 2011

Technology Management Trends In Law Schools, Carol A. Watson, Larry Reeves

Articles, Chapters and Online Publications

Discusses the role of librarians in law school technology management and analyzes technology staffing survey results for 2002, 2006, and 2010. While survey results indicate a trend toward establishing separate information technology departments within law schools, librarians are and will continue to be actively involved in law school technology.


Nanosecond Pulse Electrical Fields Used In Conjunction With Multi-Wall Carbon Nanotubes As A Potential Tumor Treatment, Michael W. Stacey, Christopher Osgood, Bhargava Subhash Kalluri, Wei Cao, Hani Elsayed-Ali, Tarek Abdel-Fattah Jan 2011

Nanosecond Pulse Electrical Fields Used In Conjunction With Multi-Wall Carbon Nanotubes As A Potential Tumor Treatment, Michael W. Stacey, Christopher Osgood, Bhargava Subhash Kalluri, Wei Cao, Hani Elsayed-Ali, Tarek Abdel-Fattah

Bioelectrics Publications

The objectives of this communication were to fabricate pure samples of multi-walled carbon nanotubes (MWCNTs) and to determine their toxicity in tumor cell lines. MWCNTs were dispersed in a concentration of the surfactant T80 that was minimally toxic. Cell-type variation in toxicity to MWCNTs was observed but was not significantly different to unexposed controls. Additionally, we investigated the increased cell killing of the pancreatic cancer cell line PANC1 when exposed to ultrashort (nanosecond) pulsed electrical fields (nsPEF) in the presence of MWCNTs as a potential form of cancer therapy. We hypothesized that the unique electronic properties of MWCNTs disrupt cell …


Nanosecond Pulsed Electric Field Induced Cytoskeleton, Nuclear Membrane And Telomere Damage Adversely Impact Cell Survival, Michael W. Stacey, P. Fox, S. Buescher, Juergen F. Kolb Jan 2011

Nanosecond Pulsed Electric Field Induced Cytoskeleton, Nuclear Membrane And Telomere Damage Adversely Impact Cell Survival, Michael W. Stacey, P. Fox, S. Buescher, Juergen F. Kolb

Bioelectrics Publications

We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and …


Electro-Gene Transfer To Skin Using A Noninvasive Multielectrode Array, Siqi Guo, Amy Donate, Gaurav Basu, Cathryn Lundberg, Loree Heller, Richard Heller Jan 2011

Electro-Gene Transfer To Skin Using A Noninvasive Multielectrode Array, Siqi Guo, Amy Donate, Gaurav Basu, Cathryn Lundberg, Loree Heller, Richard Heller

Bioelectrics Publications

Because of its large surface area and easy access for both delivery and monitoring, the skin is an attractive target for gene therapy for cutaneous diseases, vaccinations and several metabolic disorders. The critical factors for DNA delivery to the skin by electroporation (EP) are effective expression levels and minimal or no tissue damage. Here, we evaluated the non-invasive multielectrode array (MEA) for gene electrotransfer. For these studies we utilized a guinea pig model, which has been shown to have a similar thickness and structure to human skin. Our results demonstrate significantly increased gene expression 2 to 3 logs above injection …


An Apoptosis Targeted Stimulus With Nanosecond Pulsed Electric Fields (Nspefs) In E4 Squamous Cell Carcinoma, Wei Ren, Stephen J. Beebe Jan 2011

An Apoptosis Targeted Stimulus With Nanosecond Pulsed Electric Fields (Nspefs) In E4 Squamous Cell Carcinoma, Wei Ren, Stephen J. Beebe

Bioelectrics Publications

Stimuli directed towards activation of apoptosis mechanisms are an attractive approach to eliminate evasion of apoptosis, a ubiquitous cancer hallmark. In these in vitro studies, kinetics and electric field thresholds for several apoptosis characteristics are defined in E4 squamous carcinoma cells (SCC) exposed to ten 300 ns pulses with increasing electric fields. Cell death was [95% at the highest electric field and coincident with phosphatidylserine externalization, caspase and calpain activation in the presence and absence of cytochrome c release, decreases in Bid and mitochondria membrane potential (Δψm) without apparent changes reactive oxygen species levels or in Bcl2 and Bclxl levels. …


Bond Behavior Of Fiber Reinforced Polymer Bars Under Hinged Beam Conditions, Ryan James Sandstrom Jan 2011

Bond Behavior Of Fiber Reinforced Polymer Bars Under Hinged Beam Conditions, Ryan James Sandstrom

Master's Theses

The research provided in this report examines the behavior of fiber reinforced polymer (FRP) reinforcing bars, embedded in normal weight concrete (NWC) hinged beam-end specimens, tested in accordance with two laboratory conditions. Reinforcing bars of different diameter, material configuration, and finished surface preparation were tested for bond strength parameters determined in accordance with ACI Committee Report 440.3. Bond strength parameters under the first condition were tested within NWC beams at a relatively low compressive strength and minimum embedment length; the second condition allowed testing within NWC beams at twice the design compressive strength of the first condition and moderate embedment …


Analysis Of Partially Electroded Piezoelectric Actuators With Nonuniform Thickness For The Purpose Of Reducing Actuating Shear Stress Concentration By Ansys, Nan Liu, Hongping Hu Jan 2011

Analysis Of Partially Electroded Piezoelectric Actuators With Nonuniform Thickness For The Purpose Of Reducing Actuating Shear Stress Concentration By Ansys, Nan Liu, Hongping Hu

Department of Mechanical and Materials Engineering: Faculty Publications

An elastic plate with thin piezoelectric films bonded on its two major surfaces is a typical smart structure which is used in actuation and sensing. The useful deformation of the smart structure is caused by the shear stress transferring from the actuators to the elastic plate. This shear stress is concentrated at two ends of the interface between the actuator and the plate. This concentration may induce undesirable delamination of the actuator from the plate. It was theoretically proved that actuators with partially covered electrodes have a much less concentrated actuating shear stress than that with fully ones. An actuator …


Simulation Of Electrospun Nanofiber Deposition On Stationary And Moving Substrates, Linhua Liu, Yuris A. Dzenis Jan 2011

Simulation Of Electrospun Nanofiber Deposition On Stationary And Moving Substrates, Linhua Liu, Yuris A. Dzenis

Department of Mechanical and Materials Engineering: Faculty Publications

Electrospinning produces continuous fibers with diameters from single nanometers to microns by jetting polymer solutions in high electric fields. Electrospun non-woven filamentary materials attract rapidly growing interest for broad range of applications. Properties of these materials depend on their nano- and microstructure that is determined in turn by the electric field and nanofiber collector. Despite critical importance, deposition of electrospun fibers on substrates has not yet been extensively studied theoretically and new methods of nanofiber collection continue to be developed mostly empirically. The objective of this Letter was to develop and demonstrate numerical simulation of electrospun nanofiber deposition on moving …


Modeling Of Solvent Evaporation From Polymer Jets In Electrospinning, Xiang-Fa Wu, Yury Salkovskiy, Yuris A. Dzenis Jan 2011

Modeling Of Solvent Evaporation From Polymer Jets In Electrospinning, Xiang-Fa Wu, Yury Salkovskiy, Yuris A. Dzenis

Department of Mechanical and Materials Engineering: Faculty Publications

Solvent evaporation plays a critical role in nanofiber formation in electrospinning. Here, we present a nonlinear mass diffusion-transfer model describing the drying process in dilute polymer solution jets. The model is used to predict transient solvent concentration profiles in polyacrylonitrile/ N,N-dimethylformamide (PAN/DMF) jets with the initial radii ranging from 50µm down to 100 nm. Numerical simulations demonstrate high transient inhomogeneity of solvent concentration over the jet cross-section in microscopic jets. The degree of inhomogeneity decreases for finer, submicron jets. The simulated jet drying time decreases rapidly with the decreasing initial jet radius, from seconds for microjets to single milliseconds for …


The Effects Of System Reliability And Task Uncertainty On Unmanned Aerial Vehicle Operator Performance Under High Time Pressure, Manuela Jaramillo Jan 2011

The Effects Of System Reliability And Task Uncertainty On Unmanned Aerial Vehicle Operator Performance Under High Time Pressure, Manuela Jaramillo

Master's Theses - Daytona Beach

For many years, the military has understood the value and versatility of Unmanned Aerial Systems (UAS). In the recent years, UASs have sparked the interest of other fields, and in the very near future, they will be introduced into the National Airspace System (NAS). With this inclusion come new concerns. Due to the future wide range applications for UASs, it is important to explore factors, which may affect operator performance. The UAS operator task differs from that of a manned aircraft pilot. An UAS operator does not get the same sensory cues as a pilot and their field of vision …


Human Sanitary Wastes And Waste Treatment In New York City, David J. Tonjes, Christine O'Connell, Omkar Aphale, R. Lawrence Swanson Jan 2011

Human Sanitary Wastes And Waste Treatment In New York City, David J. Tonjes, Christine O'Connell, Omkar Aphale, R. Lawrence Swanson

Technology & Society Faculty Publications

Henry Hudson first sailed toNew Yorkharbor 400 years ago. Since then,New York Cityhas both affected and been affected by water quality in greaterNew YorkHarbor. In this paper, we focus on sewers, sewerage, and sewage treatment inManhattanand their effects on theHudson River. It is clear that feedbacks among drinking water quality and quantity, population, public perceptions, regulations, and estuarine water quality exist, although their strength and character have varied over time. Early land uses damaged local water supplies found on ManhattanIsland. New Yorkthen began to exploit the large fresh water resources available to its north, which helped the City to expand …


Kentucky Water Resources Research Institute Annual Technical Report Fy 2010, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2011

Kentucky Water Resources Research Institute Annual Technical Report Fy 2010, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2010 Annual Technical Report for Kentucky consolidates reporting requirements for the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each research project that was conducted during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable awards and achievements during the year.


A Method For Calibration Of Speed-Flow Curves In Hcm 2010 And Determination Of Highway Capacity, Seyed Hadii Khazraee Khoshroozi Jan 2011

A Method For Calibration Of Speed-Flow Curves In Hcm 2010 And Determination Of Highway Capacity, Seyed Hadii Khazraee Khoshroozi

Masters Theses

"This study proposes a method for calibration of speed-flow curves in a format suggested by the Highway Capacity Manual (HCM) 2010 and applies it to two sites in Missouri: a work zone on I-44 around Pacific, and a basic freeway segment on I-270 in St. Louis. The three-regime model proposed is based on the two-regime (free-flow and transition) uncongested relationship suggested by the HCM 2010, complemented with a third regime representing congested conditions. Further, this study proposes a systematic approach based on regression analysis to determine capacity i.e., the break-point (intersection) between the transition and congested regimes. The proposed method …


Laboratory Studies Of Compatibility Of Tamper Detection Materials With Improvised Explosive Device Crater Repairs, Levi Anthony Smith Jan 2011

Laboratory Studies Of Compatibility Of Tamper Detection Materials With Improvised Explosive Device Crater Repairs, Levi Anthony Smith

Masters Theses

"Past methods for road repairs of craters caused by improvised explosive devices (IEDs) on main supply routes (MSRs) and alternative supply routes (ASRs) in Iraq and Afghanistan have been problematic. Traditional temporary and permanent solutions have proven deficient by being easily penetrable or by exposing troops for long periods of time. The use of a pre-blended rapid hardening cementitious material for lED crater repair has solved issues such as quick placement of the repair and high strength of the repair within an hour of placement. However, there are still issues with IEDs being hidden in repairs tampered by or replicated …


Development Of Dna Based Active Macro-Materials For Biology And Medicine: A Review, Frank Xue Jiang, Bernard Yurke, Devendra Verma, Michelle Previtera, Rene Schloss, Noshir A. Langrana Jan 2011

Development Of Dna Based Active Macro-Materials For Biology And Medicine: A Review, Frank Xue Jiang, Bernard Yurke, Devendra Verma, Michelle Previtera, Rene Schloss, Noshir A. Langrana

Electrical and Computer Engineering Faculty Publications and Presentations

DNA was first discovered as the carrier of genetic information for the majority of the known living organisms, encoding the secret of life. Its delicate design based upon double helical structure and base pairing offers a stable and reliable media for storing hereditary codes, laying the foundation for the central dogma (Watson et al. 2003). The impact of this molecule is far reaching into scientific community and our society, as manifested in many fields, for instance, forensics (Budowle et al. 2003), besides medicine. To date, a great deal of research effort has been directed towards understanding


Hybrid Inorganic/Organic Nanostructured Tandem Solar Cells: Simulation And Fabrication Methods, Patrick Michael Boland Jr. Jan 2011

Hybrid Inorganic/Organic Nanostructured Tandem Solar Cells: Simulation And Fabrication Methods, Patrick Michael Boland Jr.

Electrical & Computer Engineering Theses & Dissertations

Organic solar cell technologies continue to be an extremely active area of scientific research. With their promise of providing low-cost, easily-processable, multi-application photovoltaics, these devices could very possibly be the most viable and practical form of renewable energy among many being explored. However, significant technological obstacles remain that must be overcome if this technology is to successfully realize the goal of providing abundant energy while simultaneously reducing dependence on fossil fuel-based sources. Compared with inorganic solar photovoltaics, power conversion efficiencies in organics are still too low to compete economically.

Much research has been accomplished over the past three decades in …


A Database For Estimating Scanner-Specific Ct Dose, Taly Gilat-Schmidt Jan 2011

A Database For Estimating Scanner-Specific Ct Dose, Taly Gilat-Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose: To develop a database for estimating scanner-specific organ dose in a voxelized patient model for any spectral shape and angular tube current modulation setting. The database enables the estimation of organ dose for both existing and novel acquisition techniques without requiring Monte Carlo simulations.

Methods: The transport of monoenergetic photons through three phantoms was simulated with the PENELOPE Monte Carlo radiation transport routines at 5 – 150 keV in 1 keV increments at 1000 projections in 0.36 degree increments. The source-to-detector distance for each simulation was 100 cm, with a source-to-isocenter distance of 50 cm. The lateral and axial …


Ductile Mode Material Removal Of Ceramics And Semiconductors, Deepak Ravindra Jan 2011

Ductile Mode Material Removal Of Ceramics And Semiconductors, Deepak Ravindra

Dissertations

Ceramics and semiconductors are hard, strong, inert and lightweight. They also have good optical properties, wide energy bandgap and high maximum current density. This combination of properties makes them ideal candidates for tribological, semiconductor, MEMS and optoelectronic applications respectively. Manufacturing these materials without causing surface and subsurface damage is extremely challenging due to their high hardness, brittle characteristics and poor machinability. However, ductile regime machining of these materials is possible due to the high-pressure phase transformation occurring in the material caused by the high compressive stresses induced by the single point diamond tool tip. In this study, to further augment …


A Cell Electrofusion Microfluidic Device Integrated With 3d Thin-Film Microelectrode Arrays, Ning Hu, Jun Yang, Shizhi Qian, Sang W. Joo, Xiaolin Zheng Jan 2011

A Cell Electrofusion Microfluidic Device Integrated With 3d Thin-Film Microelectrode Arrays, Ning Hu, Jun Yang, Shizhi Qian, Sang W. Joo, Xiaolin Zheng

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device integrated with 3D thin film microelectrode arrays wrapped around serpentine-shaped microchannel walls has been designed, fabricated and tested for cell electrofusion. Each microelectrode array has 1015 discrete microelectrodes patterned on each side wall, and the adjacent microelectrodes are separated by coplanar dielectric channel wall. The device was tested to electrofuse K562 cells under a relatively low voltage. Under an AC electric field applied between the pair of the microelectrode arrays, cells are paired at the edge of each discrete microelectrode due to the induced positive dielectrophoresis. Subsequently, electric pulse signals are sequentially applied between the microelectrode arrays …


Road Surface Mirage: A Bunch Of Hot Air?, Zhou Huaichun, Huang Zhifeng, Cheng Qiang, Lu Wei, Qiu Kui, Chen Chen, Hsu Pei-Feng Jan 2011

Road Surface Mirage: A Bunch Of Hot Air?, Zhou Huaichun, Huang Zhifeng, Cheng Qiang, Lu Wei, Qiu Kui, Chen Chen, Hsu Pei-Feng

Mechanical and Civil Engineering Faculty Publications

The inferior mirage from road surfaces is a common phenomenon, which can be easily seen in everyday life. It has been recognized in the literature as a light refraction phenomenon due to the refractive index gradient caused by the temperature gradient in the air strata above the road surfaces. However, it was also suggested that the mirage is just a phenomenon of specular reflection at grazing incidence. Because of the lack of reasonable and quantitative evidence, the generally accepted light refraction theory has not yet been refuted. Here we show some mirror-like reflection images captured from a road surface stretch …


Direct Femtosecond Laser Waveguide Writing Inside Zinc Phosphate Glass, Luke B. Fletcher, Jon J. Witcher, Neil Troy, Signo Tadeu Dos Reis, Richard K. Brow, Denise M. Krol Jan 2011

Direct Femtosecond Laser Waveguide Writing Inside Zinc Phosphate Glass, Luke B. Fletcher, Jon J. Witcher, Neil Troy, Signo Tadeu Dos Reis, Richard K. Brow, Denise M. Krol

Materials Science and Engineering Faculty Research & Creative Works

We report the relationship between the initial glass composition and the resulting microstructural changes after direct femtosecond laser waveguide writing with a 1 kHz repetition rate Ti:sapphire laser system. A zinc polyphosphate glass composition with an oxygen to phosphorus ratio of 3.25 has demonstrated positive refractive index changes induced inside the focal volume of a focusing microscope objective for laser pulse energies that can achieve intensities above the modification threshold. The permanent photo-induced changes can be used for direct fabrication of optical waveguides using single scan writing techniques. Changes to the localized glass network structure that produce positive changes in …


Predictive And Adaptive Game Development A Practical Application Of Development Models To The Independent Video Game Industry, Liam A. Hunt Jan 2011

Predictive And Adaptive Game Development A Practical Application Of Development Models To The Independent Video Game Industry, Liam A. Hunt

Theses : Honours

Through the process of researching a number of game and system development models, this study defines two archetypical development models - the predictive and the adaptive. Using each of these models, two video games have been developed in order to measure the practical effect that they can have on the design, development process and player experience of a game. Using the knowledge gained through playtesting and an analysis of the relationship between each game and its development methodology, a number of development guidelines and recommendations have been specifically constructed for use by independent games developers. The practical development and written …