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Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca Jan 2009

Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability for irrigation throughout the world has been reduced in recent years due to a combination of frequent droughts and competition for water resources among agricultural, industrial, and urban users. In addition, some major agricultural areas face moderate to significant reductions of rainfall, or changes in timing of stream flow due to changes in timing of snowmelt, as a result of global climate change. Under such conditions, sophisticated irrigation water management will be required to optimize water use efficiency and maintain sufficient levels of crop productivity and quality. A key factor to achieve these targets is the estimation of …


Regional Co2 And Latent Heat Surface Fluxes In The Southern Great Plains: Measurements, Modeling, And Scaling, W. J. Riley, Sebastien C. Biraud, Margaret S. Torn, Marc L. Fischer, David P. Billesbach, Joe A. Berry Jan 2009

Regional Co2 And Latent Heat Surface Fluxes In The Southern Great Plains: Measurements, Modeling, And Scaling, W. J. Riley, Sebastien C. Biraud, Margaret S. Torn, Marc L. Fischer, David P. Billesbach, Joe A. Berry

Department of Agricultural and Biological Systems Engineering: Faculty Publications

[1] Characterizing net ecosystem exchanges (NEE) of CO2 and sensible and latent heat fluxes in heterogeneous landscapes is difficult, yet critical given expected changes in climate and land use. We report here a measurement and modeling study designed to improve our understanding of surface to atmosphere gas exchanges under very heterogeneous land cover in the mostly agricultural U.S. Southern Great Plains (SGP). We combined three years of site-level, eddy covariance measurements in several of the dominant land cover types with regional-scale climate data from the distributed Mesonet stations and Next Generation Weather Radar precipitation measurements to calibrate a land surface …


Multi-Component Nanofibrous Scaffolds With Tunable Properties For Bone Tissue Engineering, Moncy V. Jose Jan 2009

Multi-Component Nanofibrous Scaffolds With Tunable Properties For Bone Tissue Engineering, Moncy V. Jose

All ETDs from UAB

Bone is a highly complex tissue which is an integral part of vertebrates and hence any damage has a major negative effect on the quality of life. Tissue engineering is regarded as an ideal route to resolve the issues related to the scarcity of tissue and organ for transplantation. Apart from cell line and growth factors, the choice of materials and fabrication technique for scaffold are equally important. The goal of this work was to develop a multi-component nanofibrous scaffold based on a synthetic polymer (poly(lactic-co-glycolide) (PLGA)), a biopolymer (collagen) and a biomineral (nano-hydroxyapatite (na-no-HA)) by electrospinning technique, which mimics …


Optical Nonlinear Interactions In Dielectric Nano-Suspensions, Ramy El-Ganainy Jan 2009

Optical Nonlinear Interactions In Dielectric Nano-Suspensions, Ramy El-Ganainy

Electronic Theses and Dissertations

This work is divided into two main parts. In the first part (chapters 2-7) we consider the nonlinear response of nano-particle colloidal systems. Starting from the Nernst-Planck and Smoluchowski equations, we demonstrate that in these arrangements the underlying nonlinearities as well as the nonlinear Rayleigh losses depend exponentially on optical intensity. Two different nonlinear regimes are identified depending on the refractive index contrast of the nanoparticles involved and the interesting prospect of self-induced transparency is demonstrated. Soliton stability is systematically analyzed for both 1D and 2D configurations and their propagation dynamics in the presence of Rayleigh losses is examined. We …


Gabor Domain Optical Coherence Microscopy, Supraja Murali Jan 2009

Gabor Domain Optical Coherence Microscopy, Supraja Murali

Electronic Theses and Dissertations

Time domain Optical Coherence Tomography (TD-OCT), first reported in 1991, makes use of the low temporal coherence properties of a NIR broadband laser to create depth sectioning of up to 2mm under the surface using optical interferometry and point to point scanning. Prior and ongoing work in OCT in the research community has concentrated on improving axial resolution through the development of broadband sources and speed of image acquisition through new techniques such as Spectral domain OCT (SD-OCT). In SD-OCT, an entire depth scan is acquired at once with a low numerical aperture (NA) objective lens focused at a fixed …


Femtosecond Laser Written Volumetric Diffractive Optical Elements And Their Applications, Jiyeon Choi Jan 2009

Femtosecond Laser Written Volumetric Diffractive Optical Elements And Their Applications, Jiyeon Choi

Electronic Theses and Dissertations

Since the first demonstration of femtosecond laser written waveguides in 1996, femtosecond laser direct writing (FLDW) has been providing a versatile means to fabricate embedded 3-D microstructures in transparent materials. The key mechanisms are nonlinear absorption processes that occur when a laser beam is tightly focused into a material and the intensity of the focused beam reaches the range creating enough free electrons to induce structural modification. One of the most useful features that can be exploited in fabricating photonic structures is the refractive index change which results from the localized energy deposition. The laser processing system for FLDW can …


Development Of Measurement And Modeling Techniques To Quantify Atmospheric Deposition Of Persistent, Bioaccumulative And Toxic Chemicals In The Great Lakes, Mark D. Rowe Jan 2009

Development Of Measurement And Modeling Techniques To Quantify Atmospheric Deposition Of Persistent, Bioaccumulative And Toxic Chemicals In The Great Lakes, Mark D. Rowe

Dissertations, Master's Theses and Master's Reports - Open

Measurement and modeling techniques were developed to improve over-water gaseous air-water exchange measurements for persistent bioaccumulative and toxic chemicals (PBTs). Analytical methods were applied to atmospheric measurements of hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Additionally, the sampling and analytical methods are well suited to study semivolatile organic compounds (SOCs) in air with applications related to secondary organic aerosol formation, urban, and indoor air quality.

A novel gas-phase cleanup method is described for use with thermal desorption methods for analysis of atmospheric SOCs using multicapillary denuders. The cleanup selectively removed hydrogen-bonding chemicals from samples, including much of …


Identifying Indicators Of Sustainable Development Using The Global Sustainability Quadrant Approach , Andres B. Tarte Jan 2009

Identifying Indicators Of Sustainable Development Using The Global Sustainability Quadrant Approach , Andres B. Tarte

Dissertations, Master's Theses and Master's Reports - Open

Advances in information technology and global data availability have opened the door for assessments of sustainable development at a truly macro scale. It is now fairly easy to conduct a study of sustainability using the entire planet as the unit of analysis; this is precisely what this work set out to accomplish.

The study began by examining some of the best known composite indicator frameworks developed to measure sustainability at the country level today. Most of these were found to value human development factors and a clean local environment, but to gravely overlook consumption of (remote) resources in relation …


Me-Em 2009 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Jan 2009

Me-Em 2009 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

  • Energy Systems
  • Health Systems
  • Faculty & Staff
  • Students
  • Alumni
  • Resources
  • Graduates
  • Publications
  • ME-EM Community


Modeling Integrated Decisions For A Municipal Water System With Recourse And Uncertainties: Amman, Jordan, David E. Rosenberg, Jay Lund Jan 2009

Modeling Integrated Decisions For A Municipal Water System With Recourse And Uncertainties: Amman, Jordan, David E. Rosenberg, Jay Lund

Civil and Environmental Engineering Faculty Publications

Stochastic mixed-integer optimization is used to identify a portfolio of long- and short-term supply and conservation actions for a municipal water system to cost-effectively accommodate a distribution of water shortages. Alternative robust, grey-number, and best/worst case formulations systematically explore implications of uncertainties in action costs, life spans, water volumes gained or saved, shortage levels, and shortage probabilities. A detailed example for Amman, Jordan considers 23 potential actions. Results show: (1) remarkable consistency occurs across the different modeling approaches. (2) Conserving water—reducing leakage and targeting select customers to install water efficient appliances—plays an important and growing role over time. (3) A …


An Algorithm For Identifying Novel Targets Of Transcription Factor Families: Application To Hypoxia-Inducible Factor 1 Targets, Yue Jiang, Bojan Cukic, Donald A. Adjeroh, Heath D. Skinner, Jie Lin, Qingxi J. Shen, Bing-Hua Jiang Jan 2009

An Algorithm For Identifying Novel Targets Of Transcription Factor Families: Application To Hypoxia-Inducible Factor 1 Targets, Yue Jiang, Bojan Cukic, Donald A. Adjeroh, Heath D. Skinner, Jie Lin, Qingxi J. Shen, Bing-Hua Jiang

Electrical & Computer Engineering Faculty Research

Efficient and effective analysis of the growing genomic databases requires the development of adequate computational tools. We introduce a fast method based on the suffix tree data structure for predicting novel targets of hypoxia-inducible factor 1 (HIF-1) from huge genome databases. The suffix tree data structure has two powerful applications here: one is to extract unknown patterns from multiple strings/sequences in linear time; the other is to search multiple strings/sequences using multiple patterns in linear time. Using 15 known HIF-1 target gene sequences as a training set, we extracted 105 common patterns that all occur in the 15 training genes …


Model For Alumina Nanopore-Based Optical Filter, Nathan Lehman, Rama Venkat, Robert A. Schill Jan 2009

Model For Alumina Nanopore-Based Optical Filter, Nathan Lehman, Rama Venkat, Robert A. Schill

Electrical & Computer Engineering Faculty Research

Alumina nanopore structures find applications in magnetic sensors, optical filters, and various biological devices. In this work, we present a ray-optics model for the optical filter. We present a detailed simulation and a simplified analytical expression for the reflectance as a function of the alumina parameters such as pore diameter, pore density, alumina thickness, and a function of the wavelength and angle of incidence of the illuminating plane electromagnetic wave. The reflectance vs wavelength in the range of 400–800nm obtained from the simulation and the analytical expression are compared with that of the experiments for thin and thick alumina. All …


Softcomputing Identification Techniques Of Asynchronous Machine Parameters: Evolutionary Strategy And Chemotaxis Algorithm, Nouri Benaïdja Jan 2009

Softcomputing Identification Techniques Of Asynchronous Machine Parameters: Evolutionary Strategy And Chemotaxis Algorithm, Nouri Benaïdja

Turkish Journal of Electrical Engineering and Computer Sciences

Softcomputing techniques are receiving attention as optimisation techniques for many industrial applications. Although these techniques eliminate the need for derivatives computation, they require much work to adjust their parameters at the stage of research and development. Issues such as speed, stability, and parameters convergence remain much to be investigated. This paper discusses the application of the method of reference model to determine parameters of asynchronous machines using two optimisation techniques. Softcomputing techniques used in this paper are evolutionary strategy and the chemotaxis algorithm. Identification results using the two techniques are presented and compared with respect to the conventional simplex technique …


An Intelligent Face Features Generation System From Fingerprints, Şeref Sağiroğlu, Necla Özkaya Jan 2009

An Intelligent Face Features Generation System From Fingerprints, Şeref Sağiroğlu, Necla Özkaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a novel intelligent system based on artificial neural networks was designed and introduced for generating faces from fingerprints with high accuracy. The proposed system has a number of modules including two feature enrolment modules for acquiring the fingerprints and faces into the system, two feature extractors for extracting the feature sets of fingerprint and face biometrics, an artificial neural network module that was configured with the help of Taguchi experimental design method for establishing relationships among the biometric features, a face re-constructor for building up face features from the results of the system, and a test module …


Asynchronous Replication Of Metadata Across Multi-Master Servers In Distributed Data Storage Systems, Ismail Akturk Jan 2009

Asynchronous Replication Of Metadata Across Multi-Master Servers In Distributed Data Storage Systems, Ismail Akturk

LSU Master's Theses

In recent years, scientific applications have become increasingly data intensive. The increase in the size of data generated by scientific applications necessitates collaboration and sharing data among the nation's education and research institutions. To address this, distributed storage systems spanning multiple institutions over wide area networks have been developed. One of the important features of distributed storage systems is providing global unified name space across all participating institutions, which enables easy data sharing without the knowledge of actual physical location of data. This feature depends on the ``location metadata'' of all data sets in the system being available to all …


Formation Feedback Control Of Uav Flight, Stephen Stegall Jan 2009

Formation Feedback Control Of Uav Flight, Stephen Stegall

Doctoral Dissertations and Master's Theses

This thesis is a study of formation control with autonomous unmanned aerial vehicles using the formation as feedback. There is also an investigation of formation methods presenting insight into different algorithms for formations. A rigid formation is achieved using a proportional-derivative virtual structure with a formation feedback controller. There is an emphasis on stick controlled aerodynamics. The rigid formation is verified by a simulation of a longitudinal model. Formation control ideas are presented for rigid formations.


An Experimental And Numerical Investigation Of Flapping And Plunging Wings, Taylor A. Swanson Jan 2009

An Experimental And Numerical Investigation Of Flapping And Plunging Wings, Taylor A. Swanson

Doctoral Dissertations

"Micro air vehicles, or MAVs, are of current interest for a multitude of uses to which they, being small, unmanned vehicles, are uniquely suited. Among the proposed uses are exploration, reconnaissance, and communications. They can be deployed inside buildings, where their small size, hovering capability, and maneuverability, are important factors. Due to their small size, they operate at low Reynolds numbers where conventional flying mechanisms are not advantageous. Thus, attempts have been made to learn from natural flyers like insects and birds. Natural flight is accomplished by flapping wings, and this idea has been proposed for certain types of MAVs …


Titanium Dioxide Nanoparticles Induce Oxidative Stress And Dna-Adduct Formation But Not Dna-Breakage In Human Lung Cells, Kunal Bhattacharya, Maria Davoren, Jens Boertz, Roel P.F. Schins, Eik Hoffmann, Elke Dopp Jan 2009

Titanium Dioxide Nanoparticles Induce Oxidative Stress And Dna-Adduct Formation But Not Dna-Breakage In Human Lung Cells, Kunal Bhattacharya, Maria Davoren, Jens Boertz, Roel P.F. Schins, Eik Hoffmann, Elke Dopp

Articles

Titanium dioxide (TiO2), also known as titanium (IV) oxide or anatase, is the naturally occurring oxide of titanium. It is also one of the most commercially used form. To date, no parameter has been set for the average ambient air concentration of TiO2 nanoparticles (NP) by any regulatory agency. Previously conducted studies had established these nanoparticles to be mainly non-cyto- and -genotoxic, although they had been found to generate free radicals both acellularly (specially through photocatalytic activity) and intracellularly. The present study determines the role of TiO2-NP (anatase, ∅ < 100 nm) using several parameters such as cyto- and genotoxicity, DNA-adduct formation and generation of free radicals following its uptake by human lung cells in vitro. For comparison, iron containing nanoparticles (hematite, Fe2O3, ∅ < 100 nm) were used. The results of this study showed that both types of NP were located in the cytosol near the nucleus. No particles were found inside the nucleus, in mitochondria or ribosomes. Human lung fibroblasts (IMR-90) were more sensitive regarding cyto- and genotoxic effects caused by the NP than human bronchial epithelial cells (BEAS-2B). In contrast to hematite NP, TiO2-NP did not induce DNA-breakage measured by the Comet-assay in both cell types. Generation of reactive oxygen species (ROS) was measured acellularly (without any photocatalytic activity) as well as intracellularly for both types of particles, however, the iron-containing NP needed special reducing conditions before pronounced radical generation. A high level of DNA adduct formation (8-OHdG) was observed in IMR-90 cells exposed to TiO2-NP, but not in cells exposed to hematite NP. Our study demonstrates different modes of action for TiO2- and Fe2O3-NP. Whereas TiO2-NP were able to generate elevated amounts of free radicals, which induced indirect genotoxicity mainly by DNA-adduct formation, Fe2O3-NP were clastogenic (induction of DNA-breakage) and required reducing conditions for radical formation.


Providing Academic Leadership Through The Role Of Senior Lecturer 1 (Teaching) Using The Theme Of 'Sustainable Energy' As An Example, Jim Mcgovern Jan 2009

Providing Academic Leadership Through The Role Of Senior Lecturer 1 (Teaching) Using The Theme Of 'Sustainable Energy' As An Example, Jim Mcgovern

Articles

An academic leader should lead in their particular area and should love what they are doing. An example of leadership in the area of 'sustainable energy use' is presented that involves leading through identifying and participating in the development of emerging technologies. Excellent academic leadership can be provided by a Senior Lecturer through active research, incorporating the latest developments in student-centred learning in their work and providing example and encouragement for colleagues and learners.


Regeneration Of Damaged Growth Plate Using Igf-I Plasmid-Releasing Porous Plga Scaffolds, Nirmal Ravi Jan 2009

Regeneration Of Damaged Growth Plate Using Igf-I Plasmid-Releasing Porous Plga Scaffolds, Nirmal Ravi

University of Kentucky Doctoral Dissertations

Growth plate injuries account for 15-30% of long bone fractures in children. About 10% of these result in significant growth disturbances due to formation of a boney bar. If not treated correctly, this can lead to life-lasting consequences of limb length inequalities and angular deformities. Current treatments for growth plate injuries include removal of boney bar and insertion of fat, silicone, bone cement, etc.. This treatment y is inadequate, leaving almost half of these patients with continued deformities. This dissertation reports characterization of a DNA–containing porous poly(lactic-co-glycolic acid) (PLGA) scaffold system, chondrogenesis using insulin-like growth factor I (IGF-I) plasmid-releasing scaffolds …


Design And Analysis Of Nano-Gap Enhanced Surface Plasmon Resonance Sensors, Phillip Donald Keathley Jan 2009

Design And Analysis Of Nano-Gap Enhanced Surface Plasmon Resonance Sensors, Phillip Donald Keathley

University of Kentucky Master's Theses

Surface plasmon resonance (SPR) sensors are advantageous to other techniques of sensing chemical binding, offering quantitative, real-time, label-free results. Previous work has demonstrated the effectiveness of using dual-mode SPR sensors to differentiate between surface and background effects, making the sensors more robust to dynamic environments. This work demonstrates a technique that improves upon a previously optimized planar film dual-mode SPR sensor’s LOD by introducing a periodic array of subwavelength nano-gaps throughout the plasmon supporting material. First, general figures of merit for a sensor having an arbitrary number of modes are studied. Next, the mode effective index dispersion and magnetic field …


Electronic Forms-Based Computing For Evidentiary Analysis, Andy Luse, Brian Mennecke, Anthony M. Townsend Jan 2009

Electronic Forms-Based Computing For Evidentiary Analysis, Andy Luse, Brian Mennecke, Anthony M. Townsend

Journal of Digital Forensics, Security and Law

The paperwork associated with evidentiary collection and analysis is a highly repetitive and time-consuming process which often involves duplication of work and can frequently result in documentary errors. Electronic entry of evidencerelated information can facilitate greater accuracy and less time spent on data entry. This manuscript describes a general framework for the implementation of an electronic tablet-based system for evidentiary processing. This framework is then utilized in the design and implementation of an electronic tablet-based evidentiary input prototype system developed for use by forensic laboratories which serves as a verification of the proposed framework. The manuscript concludes with a discussion …


Experimental And Numerical Study Of A Proton Exchange Membrane Electrolyzer For Hydrogen Production, Sachin S. Deshmukh Jan 2009

Experimental And Numerical Study Of A Proton Exchange Membrane Electrolyzer For Hydrogen Production, Sachin S. Deshmukh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hydrogen as a fuel source has received attention from researchers globally due to its potential to replace fossil based fuels for energy production. Research is being performed on hydrogen production, storage and utilization methods to make its use economically feasible relative to current energy sources. The PEM electrolyzer is used to produce hydrogen and oxygen using water and electricity. Focus of our study is to provide a benchmark experiment and numerical model of a single cell electrolyzer that can assist in improving the current state of understanding of this system. Parametric analysis of an experimental cell was performed to understand …


Dc Electrokinetic Transport Of Cylindrical Cells In Straight Microchannels, Ye Ai, Ali Beskok, David T. Gauthier, Sang W. Joo, Shizhi Qian Jan 2009

Dc Electrokinetic Transport Of Cylindrical Cells In Straight Microchannels, Ye Ai, Ali Beskok, David T. Gauthier, Sang W. Joo, Shizhi Qian

Biological Sciences Faculty Publications

Electrokinetic transport of cylindrical cells under dc electric fields in a straight microfluidic channel is experimentally and numerically investigated with emphasis on the dielectrophoretic (DEP) effect on their orientation variations. A two-dimensional multiphysics model, composed of the Navier-Stokes equations for the fluid flow and the Laplace equation for the electric potential defined in an arbitrary Lagrangian-Eulerian framework, is employed to capture the transient electrokinetic motion of cylindrical cells. The numerical predictions of the particle transport are in quantitative agreement with the obtained experimental results, suggesting that the DEP effect should be taken into account to study the electrokinetic transport of …


Biocompatibility Of Poly-Ε-Caprolactone-Hydroxyapatite Composite On Mouse Bone Marrow-Derived Osteoblasts And Endothelial Cells, Haiying Yu, Paul H. Wooley, Shang-You Yang Jan 2009

Biocompatibility Of Poly-Ε-Caprolactone-Hydroxyapatite Composite On Mouse Bone Marrow-Derived Osteoblasts And Endothelial Cells, Haiying Yu, Paul H. Wooley, Shang-You Yang

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Tissue-engineered bone may be developed by seeding the cells capable of both osteogenesis and vascularization on biocompatible composite scaffolds. The current study investigated the performance of mice bone marrow-derived osteogenic cells and endothelial cells as seeded on hydroxyapatite (HA) and poly-ε-caprolactone (PCL) composite scaffolds.

Methods

Mononuclear cells were induced to osteoblasts and endothelial cells respectively, which were defined by the expression of osteocalcin, alkaline phosphatase (ALP), and deposits of calcium-containing crystal for osteoblasts, or by the expression of vascular endothelial growth factor receptor-2 (VEGFR-2) and von Willebrand factor (vWF), and the formation of a capillary network in Matrigel™ …


Compensating For Expressiveness In Queries To A Content Based Music Information Retrieval System, Bryan Duggan, Brendan O'Shea, Mikel Gainza, Padraig Cunningham Jan 2009

Compensating For Expressiveness In Queries To A Content Based Music Information Retrieval System, Bryan Duggan, Brendan O'Shea, Mikel Gainza, Padraig Cunningham

Conference papers

MATT2 is a content based music information retrieval system adapted to the characteristics of traditional Irish dance music. MATT2 compensates for expressive artefacts commonly employed by traditional musicians. Specifically these are ornamentation, "the long note", reversing and phrasing. In this paper we describe the main components of MATT2 and present an experiment where we demonstrate that using this higher level knowledge of melodic similarity in traditional Irish dance music results in a significant improvement in annotation accuracy over standard approaches from the MIR literature.


Measurement Of Phonemic Degradation In Sensorineural Hearing Loss Using A Computational Model Of The Auditory Periphery, Andrew Hines, Naomi Harte Jan 2009

Measurement Of Phonemic Degradation In Sensorineural Hearing Loss Using A Computational Model Of The Auditory Periphery, Andrew Hines, Naomi Harte

Conference papers

A computational model of the auditory periphery enables faster investigation of new signal processing algorithms for hearing aids. This paper presents a study of the degradation of auditory nerve (AN) responses at a phonetic level for a range of sensorineural hearing losses. The AN model of Zilany & Bruce was used to compute responses to a diverse set of phoneme rich sentences from the TIMIT database. The characteristics of both the average discharge rate and spike timing of the responses are discussed. The experiments demonstrate that the model responses are consistent with respect to impairment and inaudible thresholds.


Error Metrics For Impaired Auditory Nerve Responses Of Different Phoneme Groups, Andrew Hines, Naomi Harte Jan 2009

Error Metrics For Impaired Auditory Nerve Responses Of Different Phoneme Groups, Andrew Hines, Naomi Harte

Conference papers

An auditory nerve model allows faster investigation of new signal processing algorithms for hearing aids. This paper presents a study of the degradation of auditory nerve (AN) responses at a phonetic level for a range of sensorineural hearing losses and flat audiograms. The AN model of Zilany & Bruce was used to compute responses to a diverse set of phoneme rich sentences from the TIMIT database. The characteristics of both the average discharge rate and spike timing of the responses are discussed. The experiments demonstrate that a mean absolute error metric provides a useful measure of average discharge rates but …


Tunable Laser Interrogation Of Surface Plasmon Resonance Sensors, Vaibhav Badjatya Jan 2009

Tunable Laser Interrogation Of Surface Plasmon Resonance Sensors, Vaibhav Badjatya

University of Kentucky Master's Theses

Surface plasmons are bound TM polarized electromagnetic waves that propagate along the interface of two materials with real dielectric constants of opposite signs. Surface plasmon resonance (SPR) sensors make use of the surface plasmon waves to detect refractive index changes occurring near this interface. For sensing purposes, this interface typically consists of a metal layer, usually gold or silver, and a liquid dielectric. SPR sensors usually measure the shift in resonance wavelength or resonance angle due to index changes adjacent to the metal layer. However this restricts the limit of detection (LOD), as the regions of low slope (intensity vs. …


Utilizing Mixed Surfactants For Simultaneous Pore Templating And Active Site Formation In Metal Oxides, Mohammed Shahidur Rahman Jan 2009

Utilizing Mixed Surfactants For Simultaneous Pore Templating And Active Site Formation In Metal Oxides, Mohammed Shahidur Rahman

University of Kentucky Doctoral Dissertations

Self-assembled nonionic alkyl glycoside surfactants are of interest for creating functional adsorption and catalytic sites at the surface of mesoporous metal oxides, but they typically impart poor long-range order when used as pore templates. Improved order and control over the functional site density may be achieved by mixing them with a cationic surfactant. To confirm this hypothesis, we investigate the lyotropic liquid crystalline (LLC) phase behavior of aqueous solutions of the functional nonionic surfactant n-dodecyl β-D-maltoside (C12G2) and cationic cetyltrimethylammonium bromide (C16TAB). A ternary phase diagram of the C16TAB-C12G2 …