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2005

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Articles 3091 - 3120 of 5573

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Relationship Between Software Metrics And Process Models, Sadia Munir Jan 2005

Analysis Of Relationship Between Software Metrics And Process Models, Sadia Munir

Theses

This thesis studies the correlation between software process models and software metrics. To support our studies we have defined a Process - Metric Evaluation Framework and derived an evaluation template from it. The template served as a basic tool in studding the relationships between various process models, artifacts and software metrics.

We have evaluated a number of process models according to our template and have identified suitable software metrics. We have also recommended a root cause analysis approach at various points of the process models.

The suggested software metrics can be derived from various product and process artifacts. They can …


Next Generation Satellite Orbital Control System, Thomas Gerard Nowak Jan 2005

Next Generation Satellite Orbital Control System, Thomas Gerard Nowak

Theses

Selection of the correct software architecture is vital for building successful software-intensive systems. Its realization requires important decisions about the organization of the system and by and large permits or prevents a system's acceptance and quality attributes such as performance and reliability. The correct architecture is essential for program success while the wrong one is a formula for disaster.

In this investigation, potential software architectures for the Next Generation Satellite Orbital Control System (NG-SOCS) are developed from compiled system specifications and a review of existing technologies. From the developed architectures, the recommended architecture is selected based on real-world considerations that …


Performance Evaluation Of Various Allocation Methods In A Heterogeneous Disk Array Architecture, Bogdan Alexandru Branzoi Jan 2005

Performance Evaluation Of Various Allocation Methods In A Heterogeneous Disk Array Architecture, Bogdan Alexandru Branzoi

Theses

Dataset attributes, such as data availability levels and access patterns, make their mapping to certain RAID levels more desirable than others. On the other hand, it is not economically viable for an installation to acquire multiple disk arrays to satisfy diverse data storage requirements. A Heterogeneous Disk Array (HDA) architecture is proposed, which allows device heterogeneity as well as RAID level heterogeneity. In other words, various disks of different types can be incorporated in a single HDA and multiple RAID schemes can coexist in the same array. The goal of this architecture is to utilize the resources of all its …


Digital Libraries And Middleware Technology, Muhammad Umar Qasim Jan 2005

Digital Libraries And Middleware Technology, Muhammad Umar Qasim

Theses

Digital libraries deliver personalized knowledge directly to their users, without being restricted to the contents of a physical library. In a digital library information from any online source can be managed and shared, making more knowledge available to users than before. The information sharing is achieved by integrating many autonomous heterogeneous systems available. The challenge is to provide users with the ability to transparently access digital library contents in spite of the heterogeneity among the information sources.

Research communities have proposed several approaches to accomplish the system integration in digital libraries. In this thesis, the working of currently employed approaches …


Flux Qubits And Readout Device With Two Independent Flux Lines, Britton Plourde, T. L. Robertson Jan 2005

Flux Qubits And Readout Device With Two Independent Flux Lines, Britton Plourde, T. L. Robertson

Physics - All Scholarship

We report measurements on two superconducting flux qubits coupled to a readout Superconducting QUantum Interference Device (SQUID). Two on-chip flux bias lines allow independent flux control of any two of the three elements, as illustrated by a two-dimensional qubit flux map. The application of microwaves yields a frequency-flux dispersion curve for 1- and 2-photon driving of the single-qubit excited state, and coherent manipulation of the single-qubit state results in Rabi oscillations and Ramsey fringes. This architecture should be scalable to many qubits and SQUIDs on a single chip.


Comparison Of Meteor Radar And Na Doppler Lidar Measurements Of Winds In The Mesopause Region Above Maui, Hawaii, S. J. Franke, X. Chu, A. Z. Liu, W. K. Hocking Jan 2005

Comparison Of Meteor Radar And Na Doppler Lidar Measurements Of Winds In The Mesopause Region Above Maui, Hawaii, S. J. Franke, X. Chu, A. Z. Liu, W. K. Hocking

Physical Sciences - Daytona Beach

The coincident measurements span 96 hours and altitudes between 80 and 100 km. Statistical comparisons are carried out on radar/lidar winds with 1 hour and 4 km time and height resolution, respectively. The RMS radar/lidar wind component differences observed in this study are in the range 12–17 m/s at altitudes below 96 km. This is smaller than the RMS differences observed in a previous Na lidar and meteor radar comparison. Lidar wind component variances exceed radar variances, and radar/lidar covariance, is nearly equal to the radar variance. Excess variance observed by the lidar is consistent with the fact that the …


Vertical Heat And Constituent Transport In The Mesopause Region By Dissipating Gravity Waves At Maui, Hawaii (20.7ºn), And Starfire Optical Range, New Mexico (35ºn), Alan Z. Liu, Chester S. Gardner Jan 2005

Vertical Heat And Constituent Transport In The Mesopause Region By Dissipating Gravity Waves At Maui, Hawaii (20.7ºn), And Starfire Optical Range, New Mexico (35ºn), Alan Z. Liu, Chester S. Gardner

Physical Sciences - Daytona Beach

Vertical heat flux profiles induced by dissipating gravity waves in the mesopause region (85–100 km altitude) are derived from Na lidar measurements of winds and temperatures at Maui (20.7ºN, 156.3ºW), Hawaii, and compared with earlier results from Starfire Optical Range (SOR, 35.0ºN, 106.5ºW), New Mexico. The heat flux profile at SOR has a single downward maximum of 2.25 ± 0.3 K m/s at 88 km, while the profile at Maui has two downward maxima of 1.25 ± 0.5 K m/s and 1.40 ± 0.5 K m/s at 87 and 95 km, respectively. The common maximum below 90 km can be …


Maui Mesosphere And Lower Thermosphere (Maui Malt) Observations Of The Evolution Of Kelvin-Helmholtz Billows Formed Near 86 Km Altitude, J. H. Hecht, Alan Z. Liu, R. L. Walterscheid, R. J. Rudy Jan 2005

Maui Mesosphere And Lower Thermosphere (Maui Malt) Observations Of The Evolution Of Kelvin-Helmholtz Billows Formed Near 86 Km Altitude, J. H. Hecht, Alan Z. Liu, R. L. Walterscheid, R. J. Rudy

Physical Sciences - Daytona Beach

Small-scale (less than 15 km horizontal wavelength) structures known as ripples have been seen in OH airglow images for nearly 30 years. The structures have been attributed to either convective or dynamical instabilities; the latter are mainly due to large wind shears, while the former are produced by superadiabatic temperature gradients. Dynamical instabilities produce Kelvin-Helmholtz (KH) billows, which have been known for many years. However, models and laboratory experiments suggest that these billows often spawn a secondary instability that is convective in nature. While laboratory investigations see evidence of such structures, the evolution of these instabilities in the atmosphere has …


Advantageous Goes Ir Results For Ash Mapping At High Latitudes: Cleveland Eruptions 2001, Yingxin Gu, William I. Rose, David J. Schneider, Gregg J. S. Bluth, M. I. Watson Jan 2005

Advantageous Goes Ir Results For Ash Mapping At High Latitudes: Cleveland Eruptions 2001, Yingxin Gu, William I. Rose, David J. Schneider, Gregg J. S. Bluth, M. I. Watson

Department of Geological and Mining Engineering and Sciences Publications

The February 2001 eruption of Cleveland Volcano, Alaska allowed for comparisons of volcanic ash detection using two-band thermal infrared (10–12 μm) remote sensing from MODIS, AVHRR, and GOES 10. Results show that high latitude GOES volcanic cloud sensing the range of about 50 to 65°N is significantly enhanced. For the Cleveland volcanic clouds the MODIS and AVHRR data have zenith angles 6–65 degrees and the GOES has zenith angles that are around 70 degrees. The enhancements are explained by distortion in the satellite view of the cloud's lateral extent because the satellite zenith angles result in a “side-looking” aspect and …


Search For Electroweak Single-Top-Quark Production In Pp̅ Collisions At √S =1.96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Jan 2005

Search For Electroweak Single-Top-Quark Production In Pp̅ Collisions At √S =1.96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We report on a search for standard model t-channel and s-channel single-top quark production in pp̅ collisions at a center of mass energy of 1.96 TeV. We use a data sample corresponding to 162 pb-1 recorded by the upgraded collider detector at Fermilab. We find no significant evidence for electroweak top quark production and set upper limits at the 95% confidence level on the production cross section, consistent with the standard model: 10.1 pb for the t-channel, 13.6 pb for the s-channel and 17.8 pb for the combined cross section of t- and s …


Smartacking: Improving Tcp Performance From The Receiving End, Daniel K. Blandford, Sally A. Goldman, Sergey Gorinsky, Yan Zhou, Daniel R. Dooly Jan 2005

Smartacking: Improving Tcp Performance From The Receiving End, Daniel K. Blandford, Sally A. Goldman, Sergey Gorinsky, Yan Zhou, Daniel R. Dooly

All Computer Science and Engineering Research

We present smartacking, a technique that improves performance of Transmission Control Protocol (TCP) via adaptive generation of acknowledgments (ACKs) at the receiver. When the bottleneck link is underutilized, the receiver transmits an ACK for each delivered data segment and thereby allows the connection to acquire the available capacity promptly. When the bottleneck link is at its capacity, the smartacking receiver sends ACKs with a lower frequency reducing the control traffic overhead and slowing down the congestion window growth to utilize the network capacity more effectively. To promote quick deployment of the technique, our primary implementation of smartacking modifies only the …


Summary Of Nutrient Enrichment Studies Of Natural Phytoplankton Populations In The Lower Hillsborough River, The Palm River, And The Alafia River Conducted On October 18 - 22, 2004, The City Of Tampa Wastewater Department Jan 2005

Summary Of Nutrient Enrichment Studies Of Natural Phytoplankton Populations In The Lower Hillsborough River, The Palm River, And The Alafia River Conducted On October 18 - 22, 2004, The City Of Tampa Wastewater Department

Reports

The Bay Study Group (BSG) conducted nutrient enrichment studies (bioassays) on natural phytoplankton population samples collected in the Lower Hillsborough River, the Palm River, and the Alafia River on October 18, 2004. The Lower Hillsborough River test site was located approximately 200m upriver of the Nebraska Avenue bridge (Lat: 28o 01.171’N; Lon: 82o 27.025’W), the Palm River test site was located approximately 300m downstream from the barrier at Structure-160 (Lat: 27o 57.308’N; Lon: 82o 22.200’W), and the Alafia River test site was located at the Hillsborough County boat ramp at Center Avenue (Lat: 27o 52.842’N; Lon: 82o 18.011’W).


On Some Generalized Transforms For Signal Decomposition And Reconstruction., Yumnam Singh Dr. Jan 2005

On Some Generalized Transforms For Signal Decomposition And Reconstruction., Yumnam Singh Dr.

Doctoral Theses

In this thesis, we propose two new subband transforms entitled ISITRA and YKSK transforms and their possible applications in image compression and encryption. Both these transforms are developed based on a common model of multiplication known as Bino’s model of multiplication. ISITRA is a convolution based transforms i.e., that both forward and inverse transform of ISITRA is based on convolution as in DWT or 2-channel filter bank. However, it is much more general than the existing DWT or 2-channel filter bank scheme in the sense that it we can get different kinds of filters in addition to the filters specified …


Essays On Dynamic Disequilibrium Models., Arpita Dhar Dr. Jan 2005

Essays On Dynamic Disequilibrium Models., Arpita Dhar Dr.

Doctoral Theses

The present dissertation is devoted to the analysis of some problems of economic growth in the framework of what has been called Disequilibrium model.Studies on economic growth have been mostly confined, with few exceptions, to the analysis of equilibrium models. But in reality there are cases where the concept of equilibrium may not be relevant and hence a disequilibrium approach is needed. The present thesis is concerned with analysing some theoretical and empirical aspects of the problem of economic growth in a disequilibrium framework. At the theoretical level, the objective has been to re-examine the conclusions of some existing equilibrium …


Amyloid-Β Protofibrils Differ From Amyloid-Β Aggregates Induced In Dilute Hexafluoroisopropanol In Stability And Morphology, Michael Nichols, Melissa Moss, Dana Reed, Stephanie Cratic-Mcdaniel, Jan Hoh, Terrone Rosenberry Jan 2005

Amyloid-Β Protofibrils Differ From Amyloid-Β Aggregates Induced In Dilute Hexafluoroisopropanol In Stability And Morphology, Michael Nichols, Melissa Moss, Dana Reed, Stephanie Cratic-Mcdaniel, Jan Hoh, Terrone Rosenberry

Chemistry & Biochemistry Faculty Works

The brains of Alzheimer’s disease (AD) patients contain large numbers of amyloid plaques that are rich in fibrils composed of 40- and 42-residue amyloid-β (Aβ) peptides. Several lines of evidence indicate that fibrillar Aβ and especially soluble Aβ aggregates are important in the etiology of AD. Recent reports also stress that amyloid aggregates are polymorphic and that a single polypeptide can fold into multiple amyloid conformations. Here we demonstrate that Aβ-(1–40) can form soluble aggregates with predominant β-structures that differ in stability and morphology. One class of aggregates involved soluble Aβ protofibrils, prepared by vigorous overnight agitation of monomeric Aβ-(1–40) …


Balanced Scaling Vectors Using Linear Combinations Of Existing Scaling Vectors, Bruce Kessler Jan 2005

Balanced Scaling Vectors Using Linear Combinations Of Existing Scaling Vectors, Bruce Kessler

Mathematics Faculty Publications

The majority of the research done into creating balanced multiwavelets has involved establishing a series of conditions on the mask of the new scaling vector by solving a large nonlinear system. The result is a completely different new function vector solution to the dilation equation with the new matrix coefficients. The research presented here will show a way to use previously-constructed orthonormal scaling vectors to generate equivalent orthonormal scaling vectors that are balanced up to the approximation order of the previous scaling vector. The technique uses linear combinations of the integer translates of the previous-constructed scaling vector.


Studies Of The Relationship Between The Structure And Properties Of Interfacial Thin Films, Mark Anderson Jan 2005

Studies Of The Relationship Between The Structure And Properties Of Interfacial Thin Films, Mark Anderson

Mark R. Anderson

No abstract is available at this time.


Amyloid-Β Protofibrils Differ From Amyloid-Β Aggregates Induced In Dilute Hexafluoroisopropanol In Stability And Morphology, Michael Nichols, Melissa A. Moss, Dana K. Reed, Stephanie Cratic-Mcdaniel, Jan H. Hoh, Terrone L. Rosenberry Jan 2005

Amyloid-Β Protofibrils Differ From Amyloid-Β Aggregates Induced In Dilute Hexafluoroisopropanol In Stability And Morphology, Michael Nichols, Melissa A. Moss, Dana K. Reed, Stephanie Cratic-Mcdaniel, Jan H. Hoh, Terrone L. Rosenberry

Michael Nichols

The brains of Alzheimer’s disease (AD) patients contain large numbers of amyloid plaques that are rich in fibrils composed of 40- and 42-residue amyloid-#1; (A#1;) peptides. Several lines of evidence indicate that fibrillar A#1; and especially soluble A#1; aggregates are important in the etiology of AD. Recent reports also stress that amyloid aggregates are polymorphic and that a single polypeptide can fold into multiple amyloid conformations. Here we demonstrate that A#1;-(1–40) can form soluble aggregates with predominant #1;-structures that differ in stability and morphology. One class of aggregates involved soluble A#1; protofibrils, prepared by vigorous overnight agitation of monomeric A#1;-(1–40) …


Circularly Polarized Laser Field-Induced Rescattering Plateaus In Electron-Atom Scattering, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace Jan 2005

Circularly Polarized Laser Field-Induced Rescattering Plateaus In Electron-Atom Scattering, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace

Anthony F. Starace Publications

We analyze the laser ellipticity dependence of n-photon differential cross sections (dσn/dΩ) for electron-atom scattering in an intense elliptically polarized laser field. We show that there exist two plateau-like structures in the dependence of dσn/dΩ on n for any ellipticity, including for the case of circular polarization. We present numerical predictions for e-H scattering in a CO2-laser field and an analytical description of the plateau features in terms of the rescattering scenario.


A Framework For Extraction Plans And Heuristics In An Ontology-Based Data-Extraction System, Alan E. Wessman Jan 2005

A Framework For Extraction Plans And Heuristics In An Ontology-Based Data-Extraction System, Alan E. Wessman

Theses and Dissertations

Extraction of information from semi-structured or unstructured documents, such as Web pages, is a useful yet complex task. Research has demonstrated that ontologies may be used to achieve a high degree of accuracy in data extraction while maintaining resiliency in the face of document changes. Ontologies do not, however, diminish the complexity of a data-extraction system. As research in the field progresses, the need for a modular data-extraction system that de-couples the various functional processes involved continues to grow.

In this thesis we propose a framework for such a system. The nature of the framework allows new algorithms and ideas …


Planar-To-Tubular Structural Transition In Boron Clusters: B20 As The Embryo Of Single-Walled Boron Nanotubes, Boggavarapu Kiran, Satya S. Bulusu, Hua-Jin Zhai, Soohaeng Yoo, Xiao Cheng Zeng, Lai-Sheng Wang Jan 2005

Planar-To-Tubular Structural Transition In Boron Clusters: B20 As The Embryo Of Single-Walled Boron Nanotubes, Boggavarapu Kiran, Satya S. Bulusu, Hua-Jin Zhai, Soohaeng Yoo, Xiao Cheng Zeng, Lai-Sheng Wang

Xiao Cheng Zeng Publications

Experimental and computational simulations revealed that boron clusters, which favor planar (2D) structures up to 18 atoms, prefer 3D structures beginning at 20 atoms. Using global optimization methods, we found that the B20 neutral cluster has a double-ring tubular structure with a diameter of 5.2 Å. For the B20- anion, the tubular structure is shown to be isoenergetic to 2D structures, which were observed and confirmed by photoelectron spectroscopy. The 2D-to-3D structural transition observed at B20, reminiscent of the ring-to-fullerene transition at C20 in carbon clusters, suggests it may be considered as the embryo …


Use Of Michelson And Fabry–Perot Interferometry For Independent Determination Of The Refractive Index And Physical Thickness Of Wafers, Glen D. Gillen, Shekhar Guha Jan 2005

Use Of Michelson And Fabry–Perot Interferometry For Independent Determination Of The Refractive Index And Physical Thickness Of Wafers, Glen D. Gillen, Shekhar Guha

Physics

We present a method to independently measure the refractive index and the thickness of materials having flat and parallel sides by using a combination of Michelson and Fabry-Perot interferometry techniques. The method has been used to determine refractive-index values in the infrared with uncertainties in the third decimal place and thicknesses accurate to within ± 5 µm for materials at room and cryogenic temperatures.


The Clustering Of Regression Models Method With Applications In Gene Expression Data, Li-Xuan Qin, Steven G. Self Jan 2005

The Clustering Of Regression Models Method With Applications In Gene Expression Data, Li-Xuan Qin, Steven G. Self

UW Biostatistics Working Paper Series

Identification of differentially expressed genes and clustering of genes are two important and complementary objectives addressed with gene expression data. For the differential expression question, many "per-gene" analytic methods have been proposed. These methods can generally be characterized as using a regression function to independently model the observations for each gene; various adjustments for multiplicity are then used to interpret the statistical significance of these per-gene regression models over the collection of genes analyzed. Motivated by this common structure of per-gene models, we propose a new model-based clustering method -- the clustering of regression models method, which groups genes that …


Serologic Evidence Of Exposure Of Wild Mammals To Flavivirusesin The Central And Eastern United States , J. Jeffrey Root, Jeffrey S. Hall, Robert G. Mclean, Nicole L. Marlenee, Barry J. Beaty, Justin Gansowski, Larry Clark Jan 2005

Serologic Evidence Of Exposure Of Wild Mammals To Flavivirusesin The Central And Eastern United States , J. Jeffrey Root, Jeffrey S. Hall, Robert G. Mclean, Nicole L. Marlenee, Barry J. Beaty, Justin Gansowski, Larry Clark

United States Department of Agriculture Wildlife Services: Staff Publications

Serosurveys were conducted to obtain flavivirus and West Nile virus (WNV) seroprevalence data from mammals. Sera from 513 small- and medium-sized mammals collected during late summer and fall 2003 from Colorado, Louisiana, New York, Ohio, and Pennsylvania were screened for flavivirus-specific antibodies. Sera samples containing antibody to flaviviruses were screened for WNV-specific antibodies by epitope-blocking enzyme-linked immunosorbent assays and confirmed with plaque reduction neutralization tests. Prevalence of WNV antibodies among study sites ranged from 0% to 42.8% among the mammal communities sampled. High prevalence rates for WNV were noted among raccoons (100%, with a very small sample size, N 2), …


Atomic Force Microscopy-Based Experimental Setup For Studying Domain Switching Dynamics In Ferroelectric Capacitors, C. Dehoff, B. J. Rodriguez, A. I. Kingon, R. J. Nemanich, Alexei Gruverman, J. S. Cross Jan 2005

Atomic Force Microscopy-Based Experimental Setup For Studying Domain Switching Dynamics In Ferroelectric Capacitors, C. Dehoff, B. J. Rodriguez, A. I. Kingon, R. J. Nemanich, Alexei Gruverman, J. S. Cross

Alexei Gruverman Publications

This article describes an experimental setup for combined measurements of domain switching dynamics and switching currents in micrometer scale ferroelectric capacitors. The setup is based on a commercial atomic force microscope (AFM) that is equipped with a piezoresponse mode for domain imaging and with a wide bandwidth current amplifier for switching current recording. The setup allows combined domain/current measurements in capacitors as small as 1 μm2 with switching times resolved down to 10 ns. The incorporation of switching current measurement capability into piezoresponse AFM makes detailed analysis of switching behavior in ferroelectric memory devices possible.


Direct Evidence That The Reaction Intermediate Of Metallo-Β-Lactamase L1 Is Metal Bound, James D. Garrity, Brian Bennett, Michael W. Crowder Jan 2005

Direct Evidence That The Reaction Intermediate Of Metallo-Β-Lactamase L1 Is Metal Bound, James D. Garrity, Brian Bennett, Michael W. Crowder

Physics Faculty Research and Publications

In an effort to probe the structure of the reaction intermediate of metallo-β-lactamase L1 when reacted with nitrocefin and other β-lactams, time-dependent absorption and rapid-freeze-quench (RFQ) EPR spectra were obtained using the Co(II)-substituted form of the enzyme. When using nitrocefin as the substrate, time-dependent absorption spectra demonstrate that Co(II)-substituted L1 utilizes a reaction mechanism, similar to that of the native Zn(II) enzyme, in which a short-lived intermediate forms. RFQ-EPR spectra of this intermediate demonstrate that the binding of substrate results in a change in the electronic properties of one or both of the Co(II)'s in the enzyme …


Effect Of Bio-Optical Parameter Variability On The Remote Estimation Of Chlorophyll-A Concentration In Turbid Productive Waters: Experimental Results, Giorgio Dall'olmo, Anatoly A. Gitelson Jan 2005

Effect Of Bio-Optical Parameter Variability On The Remote Estimation Of Chlorophyll-A Concentration In Turbid Productive Waters: Experimental Results, Giorgio Dall'olmo, Anatoly A. Gitelson

School of Natural Resources: Faculty Publications

The analytical development and underlying hypothesis of a three-band algorithm for estimating chlorophyll-a concentration ([Chla]) in turbid productive waters are presented. The sensitivity of the algorithm to the spectral location of the bands used is analyzed. A large set of experimental observations ([Chla] varied between 4 and 217 mg m-3 and turbidity between 2 and 78 nephelometric turbidity units) was used to calibrate and validate the algorithm. It was found that the variability of the chlorophyll-a fluorescence quantum yield and of the chlorophyll-a specific absorption coefficient can reduce considerably the accuracy of remote predictions of [Chla]. Instead of parameterizing …


In Situ Anomalous Small-Angle X-Ray Scattering From Metal Particles In Supported-Metal Catalysts. Ii. Results, H. Brumberger, D. Hagrman, Jerry Goodisman, K. D. Finkelstein Jan 2005

In Situ Anomalous Small-Angle X-Ray Scattering From Metal Particles In Supported-Metal Catalysts. Ii. Results, H. Brumberger, D. Hagrman, Jerry Goodisman, K. D. Finkelstein

Chemistry - All Scholarship

Information about the metal phase in a supported-metal catalyst can be obtained using anomalous small-angle X-ray scattering (ASAXS). The difference between the scattering profiles for SAXS at two different wavelengths near the metal's absorption edge is essentially the scattering of the metal alone. Novel in situ ASAXS measurements are made on mordenite impregnated with platinum metal while the temperature and composition of gas in the sample cell are changed. Measurements are made 62 times during treatment of the catalyst. The metal particles are assumed to be randomly distributed spheres with N(R)dR = number of spheres with radii between R and …


Five New Extrasolar Planets, Geoffrey W. Marcy, R. Paul Butler, Steve Vogt, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson Jan 2005

Five New Extrasolar Planets, Geoffrey W. Marcy, R. Paul Butler, Steve Vogt, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson

Information Systems and Engineering Management Research Publications

We report multiple Doppler measurements of five nearby FGK main-sequence stars and subgiants obtained during the past 4-6 yr at the Keck Observatory. These stars, namely, HD 183263, HD 117207, HD 188015, HD 45350, and HD 99492, all exhibit coherent variations in their Doppler shifts consistent with a planet in Keplerian motion. The five new planets occupy known realms of planetary parameter space, including a wide range of orbital eccentricities, e = 0-0.78, and semimajor axes, 0.1-3.8 AU, that provide further statistical information about the true distributions of various properties of planetary systems. One of the planets, HD 99492b, has …


Effect Of Scaling On Hydraulic Conductivity In A Karst Aquifer, Vincent J. Difrenna Jan 2005

Effect Of Scaling On Hydraulic Conductivity In A Karst Aquifer, Vincent J. Difrenna

FIU Electronic Theses and Dissertations

Hydraulic conductivity was determined for samples from the Biscayne Aquifer in Miami Florida at bench and field scales. Hydraulic conductivity values obtained were examined for increase due to scale and for anisotropy. Bench scale testing was performed on Key Largo Limestone cubes for total porosity, effective porosity, and hydraulic conductivity. Total porosity was determined by drying and weighing, while effective porosity was determined by submersion. Hydraulic conductivity was determined in a permeameter for each axis of each cube. Field scale testing of hydraulic conductivity was performed with slug tests in the Miami Oolite Formation at the Homestead General Airport. Aquifer …