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2004

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Full-Text Articles in Engineering

Immunogold Labeling To Enhance Contrast In Optical Coherence Microscopy Of Tissue Engineered Corneal Constructs, Chris B. Raub, Elizabeth J. Orwin, Richard C. Haskell Sep 2004

Immunogold Labeling To Enhance Contrast In Optical Coherence Microscopy Of Tissue Engineered Corneal Constructs, Chris B. Raub, Elizabeth J. Orwin, Richard C. Haskell

All HMC Faculty Publications and Research

Our lab has used an optical coherence microscope (OCM) to assess both the structure of tissue-engineered corneal constructs and their transparency. Currently, we are not able to resolve cells versus collagen matrix material in the images produced. We would like to distinguish cells in order to determine if they are viable while growing in culture and also if they are significantly contributing to the light scattering in the tissue. In order to do this, we are currently investigating the use of immunogold labeling. Gold nanoparticles are high scatterers and can create contrast in images. We have conjugated gold nanoparticles to …


Optical Modeling Of Iridium Thin Film Erosion Under Oxygen Plasma Exposure*, Li Yan, John A. Woollam Sep 2004

Optical Modeling Of Iridium Thin Film Erosion Under Oxygen Plasma Exposure*, Li Yan, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

This work is motivated by interest in use of iridium metal films in the space environment. Optical metrology is a sensitive tool for study of film roughness, optical constants, and microstructural properties. In the present paper, in situ spectroscopic ellipsometry is applied to monitor oxygen plasma etching of films of iridium/chromium on fused silica substrates, using an electron cyclotron resonance plasma source. Optical modeling allows for a fundamental understanding of the plasma etching mechanism. Analysis of spectroscopic psi and delta data at selected time slices suggests the iridium film is etched away gradually upon plasma irradiation, while showing no signs …


Vertical Wall Loads In A Model Grain Bin With Non-Axial Internal Inserts, Marek Molenda, Michael D. Montross, Jozef Horabik, Sidney A. Thompson Sep 2004

Vertical Wall Loads In A Model Grain Bin With Non-Axial Internal Inserts, Marek Molenda, Michael D. Montross, Jozef Horabik, Sidney A. Thompson

Biosystems and Agricultural Engineering Faculty Publications

A study was conducted to estimate the degree of load asymmetry in a bin with non-axial internal inserts. Internal inserts in the form of an annulus segment were attached to the wall, and their influence on vertical wall loads during centric filling and discharge in a model bin were measured. Wall and floor loads were measured in a corrugated-wall model grain bin with a diameter of 2.44 m and a height of 7.3 m filled with soft red winter wheat to a depth of 6.7 m (height-to-diameter ratio of 2.75). Tests were conducted with inserts that extended circumferentially 30°, 60°, …


Seasonal Aeration Rates For The Eastern United States Based On Long-Term Weather Patterns, Michael D. Montross, Samuel G. Mcneill, Thomas C. Bridges Sep 2004

Seasonal Aeration Rates For The Eastern United States Based On Long-Term Weather Patterns, Michael D. Montross, Samuel G. Mcneill, Thomas C. Bridges

Biosystems and Agricultural Engineering Faculty Publications

Most aeration fans are sized to produce a minimum airflow rate of 0.1 m3/min/t (0.1 cfm/bu) in on-farm grain storage structures. At this airflow rate a significant amount of time is required to move a cooling front completely through a bin. The desired grain temperature and prevailing weather conditions will have a significant effect on required fan size. Thirty years of weather data were analyzed for the eastern United States to determine the amount of time available in temperature windows between 0 to 15.C and 0 to 17.C. Contour maps were generated with ArcMap 8.3 for the percentage …


Mushy-Zone Rayleigh Number To Describe Macrosegregation And Channel Segregate Formation During Directional Solidification Of Metallic Alloys, Surendra N. Tewari, R. Tiwari, G. Magadi Sep 2004

Mushy-Zone Rayleigh Number To Describe Macrosegregation And Channel Segregate Formation During Directional Solidification Of Metallic Alloys, Surendra N. Tewari, R. Tiwari, G. Magadi

Chemical & Biomedical Engineering Faculty Publications

A recently defined mushy-zone Rayleigh number (R-aM) that includes side-branching contributions to the mushy-zone permeability has been examined for its correlation with the longitudinal macrosegregation and channel segregate formation. The Rayleigh number shows (1) a strong correlation between the extent of longitudinal macrosegregation and increase in the mushy-zone convection and (2) a good ability to predict the formation of channel segregates during directional solidification.


Flight Physician - September, 2004, Civil Aviation Medical Association Sep 2004

Flight Physician - September, 2004, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twenty page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.


Logic Programs And Connectionist Networks, Pascal Hitzler, Steffen Holldobler, Anthony K. Seda Sep 2004

Logic Programs And Connectionist Networks, Pascal Hitzler, Steffen Holldobler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

Graphs of the single-step operator for first-order logic programs—displayed in the real plane—exhibit self-similar structures known from topological dynamics, i.e., they appear to be fractals, or more precisely, attractors of iterated function systems. We show that this observation can be made mathematically precise. In particular, we give conditions which ensure that those graphs coincide with attractors of suitably chosen iterated function systems, and conditions which allow the approximation of such graphs by iterated function systems or by fractal interpolation. Since iterated function systems can easily be encoded using recurrent radial basis function networks, we eventually obtain connectionist systems which …


Default Reasoning Over Domains And Concept Hierarchies, Pascal Hitzler Sep 2004

Default Reasoning Over Domains And Concept Hierarchies, Pascal Hitzler

Computer Science and Engineering Faculty Publications

W.C. Rounds and G.-Q. Zhang have proposed to study a form of disjunctive logic programming generalized to algebraic domains [1]. This system allows reasoning with information which is hierarchically structured and forms a (suitable) domain. We extend this framework to include reasoning with default negation, giving rise to a new nonmonotonic reasoning framework on hierarchical knowledge which encompasses answer set programming with extended disjunctive logic programs. We also show that the hierarchically structured knowledge on which programming in this paradigm can be done, arises very naturally from formal concept analysis. Together, we obtain a default reasoning paradigm for conceptual …


Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos Sep 2004

Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos

Electrical and Computer Engineering Faculty Research & Creative Works

To accurately identify the site of origin of a tumor is crucial to cancer diagnosis and treatment. With the emergence of DNA microarray technologies, constructing gene expression profiles for different cancer types has already become a promising means for cancer classification. In addition to binary classification, the discrimination of multiple tumor types is also important semi-supervised ellipsoid ARTMAP (ssEAM) is a novel neural network architecture rooted in adaptive resonance theory suitable for classification tasks. ssEAM can achieve fast, stable and finite learning and create hyper-ellipsoidal clusters inducing complex nonlinear decision boundaries. Here, we demonstrate the capability of ssEAM to discriminate …


Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva Sep 2004

Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

Electrical and Computer Engineering Faculty Publications

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the …


Device Discovery In Frequency Hopping Wireless Ad Hoc Networks, Brian S. Peterson Sep 2004

Device Discovery In Frequency Hopping Wireless Ad Hoc Networks, Brian S. Peterson

Theses and Dissertations

This research develops a method for efficient discovery of wireless devices for a frequency hopping spread spectrum, synchronous, ad hoc network comprised of clustered sub-networks. The Bluetooth wireless protocol serves as the reference protocol. The development of a discovery, or outreach, method for scatternets requires the characterization of performance metrics of Bluetooth piconets, many of which are unavailable in literature. Precise analytical models characterizing the interference caused to Bluetooth network traffic by inquiring devices, the probability mass function of packet error rates between arbitrary pairs of Bluetooth networks, and Bluetooth discovery time distribution are developed. Based on the characterized performance …


Role Of Plasticity On Fretting Fatigue Behavior Of Ti-6al-4v, Kisu Shin Sep 2004

Role Of Plasticity On Fretting Fatigue Behavior Of Ti-6al-4v, Kisu Shin

Theses and Dissertations

Fretting fatigue generally leads to the degradation of the fatigue strength of a material due to cyclic micro-slip between two contacting materials. Fretting fatigue is regarded as an important issue in designing aerospace structures. While many studies have evaluated fretting fatigue behavior under elastic deformation conditions, few studies have focused on fretting fatigue behavior under elastic-plastic deformation conditions. The primary goal of this study was to characterize the fretting fatigue crack initiation behavior in the presence of plasticity. Experimental tests were performed using pad configurations involving elastic-plastic deformations. In order to calculate stress distributions under elastic-plastic fretting fatigue conditions, FEA …


Analytical Solution For Low-Thrust Minimum Time Control Of A Satellite Formation, John Sang-Pil Seo Sep 2004

Analytical Solution For Low-Thrust Minimum Time Control Of A Satellite Formation, John Sang-Pil Seo

Theses and Dissertations

Satellite formations or distributed satellite systems provide advantages not feasible with single satellites. Efficient operation of this platform requires the use of optimal control of the entire satellite formation. While the optimal control theory is well established, only a very simple dynamical system affords an analytical solution. Any practical optimal control problem solves the resulting two-point boundary value (TPBV) problem numerically. The relative satellite dynamics using Hill's coordinate system and approximations made by Clohessy and Wiltshire, combined with body-fixed thruster control, result in a linearized dynamic system. This dissertation provides the analysis for the minimum time satellite formation control by …


Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan Sep 2004

Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

In this study, yttrium-stabilized zirconia (YSZ) thin films 1-2 μm thick electrolyte have been prepared using NiO-YSZ anode as substrates. Fuel cell test was conducted with the single chamber configuration in methane-air gas mixture using (la,Sr)(Co,Fe) O3 (LSCF) as the cathode. Test results showed that the open-circuit voltage to be >0.8 V, with power density as high as 0.12 W cm−2. It was also shown that gas flow rate has a large influence on the performance of the fuel cell, which indicates the importance of the geometrical design for anode support fuel cell system.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 1, September 2004, College Of Engineering And Computer Science, Wright State University Sep 2004

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 1, September 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Sustainable Water Supply In Ireland, Liam Mccarton, Sean O'Hogain Sep 2004

Sustainable Water Supply In Ireland, Liam Mccarton, Sean O'Hogain

Reports

Sustainable water technology is concerned with the complete range of technologies, techniques, products and processes that will enable humankind to reduce the impact of water production and water consumption on the environment and to establish a more sustainable mode of development. The concept of sustainable development has gained wide usage over the past 15 years in an attempt to balance development needs and environmental protection. The Brundtland Report of the World Commission on Environment and Development, Our Common Future (1987) identified sustainable development as a global objective, which involved economic, social and environmental values. It defined sustainable development as ‘ …


Safety And Health Concerns For Kytc And Contractor Personnel, Theodore Hopwood Ii, Sudhir Palle Sep 2004

Safety And Health Concerns For Kytc And Contractor Personnel, Theodore Hopwood Ii, Sudhir Palle

Kentucky Transportation Center Research Report

This study was initiated to provide a review of safety and health issues related to Kentucky Transportation Cabinet (KYTC) construction activities including both KYTC and contractor personnel. Work included a literature search, interviews with KYTC resident engineers, and both a survey of and subsequent meeting with district construction safety coordinators. Recommendations are provided for implementing changes to improve safety and health regulatory compliance for both KYTC and contractor personnel.


Analysis Of Traffic Crash Data In Kentucky (1999 - 2003), Eric R. Green, Kenneth R. Agent, Jerry G. Pigman, Monica L. Barrett Sep 2004

Analysis Of Traffic Crash Data In Kentucky (1999 - 2003), Eric R. Green, Kenneth R. Agent, Jerry G. Pigman, Monica L. Barrett

Kentucky Transportation Center Research Report

This report documents an analysis of traffic crash data in Kentucky for the years of 1999 through 2003. A primary objective of this study was to determine average crash statistics for Kentucky highways. Average and critical numbers and rates of crashes were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky's procedure to identify locations that have abnormal rates or numbers of crashes.

The other primary objective of this study was to provide data that can be used in the preparation of the problem identification portion of Kentucky's Annual Highway Safety …


Run-Time Modification Of The Class Hierarchy In A Live Java Development Environment, Joel R. Brandt, Kenneth J. Goldman Sep 2004

Run-Time Modification Of The Class Hierarchy In A Live Java Development Environment, Joel R. Brandt, Kenneth J. Goldman

All Computer Science and Engineering Research

Class hierarchy design is central to object-oriented software development. However, it is sometimes difficult for developers to anticipate all the implications of a design until implementation is underway. To support experimentation with different designs, we extend prior work on live development environments to allow run-time modification of the class hierarchy. The result is a more fluid object-oriented development process, in which immediate feedback from the executing program can be used to guide hierarchy design. This paper presents a framework and developer support for run-time modification of class inheritance relations in JPie, a live visual programming environment for Java. Most notably, …


Frictional Resistance Of Aggregates For Hot-Mix Asphalt Pavements, Joan Patricia O'Brien, John E. Haddock Sep 2004

Frictional Resistance Of Aggregates For Hot-Mix Asphalt Pavements, Joan Patricia O'Brien, John E. Haddock

JTRP Technical Reports

In 1997 the Indiana Department of Transportation adopted the Superpave mixture design method and attendant specifications for hot-mix asphalt pavements. Prior to Superpave, the Indiana Department of Transportation aggregate frictional requirements were based on average daily traffic volumes and were divided into low, medium, and high volume categories. With the implementation of Superpave in Indiana, aggregate frictional requirements were reassigned to categories based on equivalent single axle load values. The purpose of the research is to determine whether average daily traffic or equivalent single axle load has a greater effect on the frictional resistance of a hot-mix asphalt pavement, to …


Developments Of The Midwest Guardrail System For Standard And Reduced Post Spacing And In Combination With Curbs, Karla A. Polivka, Dean L. Sicking, John R. Rohde, Robert W. Bielenberg M.S.C.E., E.I.T., Ronald K. Faller, John D. Reid, James C. Holloway, Beau D. Kuipers Sep 2004

Developments Of The Midwest Guardrail System For Standard And Reduced Post Spacing And In Combination With Curbs, Karla A. Polivka, Dean L. Sicking, John R. Rohde, Robert W. Bielenberg M.S.C.E., E.I.T., Ronald K. Faller, John D. Reid, James C. Holloway, Beau D. Kuipers

Nebraska Department of Transportation: Research Reports

No abstract provided.


Every Polynomial-Time 1-Degree Collapses If And Only If P=Pspace, Stephen A. Fenner, Stuart A. Kurtz, James S. Royer Sep 2004

Every Polynomial-Time 1-Degree Collapses If And Only If P=Pspace, Stephen A. Fenner, Stuart A. Kurtz, James S. Royer

Faculty Publications

No abstract provided.


Map Estimation For Hyperspectral Image Resolution Enhancement Using An Auxiliary Sensor, Russell C. Hardie, Michael T. Eismann, Gregory L. Wilson Sep 2004

Map Estimation For Hyperspectral Image Resolution Enhancement Using An Auxiliary Sensor, Russell C. Hardie, Michael T. Eismann, Gregory L. Wilson

Electrical and Computer Engineering Faculty Publications

This paper presents a novel maximum a posteriori (MAP) estimator for enhancing the spatial resolution of an image using co-registered high spatial-resolution imagery from an auxiliary sensor. Here we focus on the use of high-resolution panchomatic data to enhance hyperspectral imagery. However, the estimation framework developed allows for any number of spectral bands in the primary and auxiliary image. The proposed technique is suitable for applications where some correlation, either localized or global, exists between the auxiliary image and the image being enhanced. To exploit localized correlations, a spatially varying statistical model, based on vector quantization, is used. Another important …


Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee Sep 2004

Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

The final two papers are concerned with the analysis of novel holograms. Banerjee et al. investigate holographic recording and reconstruction for edge-lit holograms recorded in a 90-degree geometry. Various cases of recording and readout that incorporate propagational diffraction have been modeled. It is shown that the 90-degree geometry can result in beam shaping, as evidenced through preliminary experimental results with photorefractive lithium niobate. Nguyen et al. propose a new approach for designing computer-generated holograms. An artificial neural network is used to initiate the genetic algorithm so that the high computation cost of genetic algorithms for synthesizing holograms is significantly reduced …


Do Microcracks Decrease Or Increase Fatigue Resistance In Cortical Bone?, O. S. Sobelman, J. C. Gibeling, S. M. Stover, S. J. Hazelwood, O. C. Yeh, D. R. Shelton, R. B. Martin Sep 2004

Do Microcracks Decrease Or Increase Fatigue Resistance In Cortical Bone?, O. S. Sobelman, J. C. Gibeling, S. M. Stover, S. J. Hazelwood, O. C. Yeh, D. R. Shelton, R. B. Martin

Biomedical Engineering

Fatigue of cortical bone produces microcracks; it has been hypothesized that these cracks are analogous to those occurring in engineered composite materials and constitute a similar mechanism for fatigue resistance. However, the numbers of these linear microcracks increase substantially with age, suggesting that they contribute to increased fracture incidence among the elderly. To test these opposing hypotheses, we fatigued 20 beams of femoral cortical bone from elderly men and women in load-controlled four point bending having initial strain ranges of 3000 or 5000 microstrain. Loading was stopped at fracture or 106 cycles, whichever occurred first, and microcrack density and length …


Varying The Time Delay Of An Action Potential Elicited With A Neural-Electronic Stimulator, Robert B. Szlavik, Frank Jenkins Sep 2004

Varying The Time Delay Of An Action Potential Elicited With A Neural-Electronic Stimulator, Robert B. Szlavik, Frank Jenkins

Biomedical Engineering

There have been various theoretical and experimental studies presented in the literature that focus on interfacing neurons with discrete electronic devices such as transistors. It has also been demonstrated experimentally that neural-electronic devices can be used to elicit action potentials in a target neuron in close proximity to the neural-electronic stimulator. The time delay between stimulus and the onset of the neural action potential can be varied by varying the pulse amplitude and width generated by the neural-electronic stimulator (transistor).


Determining Suitability Of A Fly Ash For Silica Extraction And Zeolite Synthesis, Natàlia Moreno, Xavier Querol, Angel López-Soler, José Manuel Andres, Maria Janssen, Henk Nugteren, Mark R. Towler, Kenneth Stanton Sep 2004

Determining Suitability Of A Fly Ash For Silica Extraction And Zeolite Synthesis, Natàlia Moreno, Xavier Querol, Angel López-Soler, José Manuel Andres, Maria Janssen, Henk Nugteren, Mark R. Towler, Kenneth Stanton

Chemical and Biochemical Engineering Faculty Research & Creative Works

Zeolitic material is obtained from fly ash both by direct conversion of the ash or from SiO2 extracts obtained from fly ash. This study focuses on determining the suitability of a fly ash for SiO2 extraction and for zeolite synthesis by direct conversion. The SiO2 extraction experiments from different fly ashes show that the main parameters governing the SiO2 extraction are: (a) a high bulk SiO2 content (> 52%, for obtaining an extraction yield of 100 g SiO2 kg-1) in the starting fly ash, (b) a high proportion (> 55%) of the bulk SiO …


Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman Sep 2004

Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

Issues associated with boost converter design and performance are investigated when a low input voltage is used. Low-input-voltage sources include single fuel cells, single solar cells, and thermoelectric devices. The primary context is interfacing single micro fuel cells to portable electronic loads, such as mobile phones. Efficiency and circuit startup are the two most difficult issues for a low-cost design. It is shown in theory and experiment that the boost converter has a voltage collapse point. A simple startup technique is proposed that is appropriate for some applications.


Novel Yttrium-Stabilized Zirconia Polymeric Precursor For The Fabrication Of Thin Films, Roger M. Smith, X.-D. Zhou, Wayne Huebner, Harlan U. Anderson Sep 2004

Novel Yttrium-Stabilized Zirconia Polymeric Precursor For The Fabrication Of Thin Films, Roger M. Smith, X.-D. Zhou, Wayne Huebner, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

An acetate-based polymeric precursor for producing yttrium-stabilized zirconia (YSZ) was developed. The precursor was prepared under ambient conditions and contains only yttrium and zirconium cations. Dense, crack-free films were fabricated with this precursor on alumina substrates at a rate of 60 nm per deposition, producing polycrystalline YSZ at temperatures as low as 600 °C. Grain growth in thin YSZ films followed Arrhenius equation with an activation energy approximately 0.45 eV. The residual strain in YSZ films decreased with increasing annealing temperature from 600 to 900 °C.


Pm Manufacturing Research Boosted By Continuous Sintering Furnace, Joseph William Newkirk Sep 2004

Pm Manufacturing Research Boosted By Continuous Sintering Furnace, Joseph William Newkirk

Materials Science and Engineering Faculty Research & Creative Works

University of Missouri-Rolla has recently acquired a Fluidtherm laboratory continuous sintering furnace. Custom designed and built for PM research, the furnace will allow current efforts in sintering development, pressure gas quenching of PM steels, optimisation of toughness and fatigue properties of PM parts, and production of metal matrix composites to be enhanced and extended.