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Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme, Eli S. Saber, Wencheng Wu, Kartheek Chandu Dec 2006

Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme, Eli S. Saber, Wencheng Wu, Kartheek Chandu

Articles

We describe a method for automatically classifying image-quality defects on printed documents. The proposed approach accepts a scanned image where the defect has been localized a priori and performs several appropriate image processing steps to reveal the region of interest. A mask is then created from the exposed region to identify bright outliers. Morphological reconstruction techniques are then applied to emphasize relevant local attributes. The classification of the defects is accomplished via a customized tree classifier that utilizes size or shape attributes at corresponding nodes to yield appropriate binary decisions. Applications of this process include automated/assisted diagnosis and repair of …


The Complexity Of Computing The Size Of An Interval, Lane A. Hemaspaandra, Christopher M. Homan, Sven Kosub, Klaus W. Wagner Dec 2006

The Complexity Of Computing The Size Of An Interval, Lane A. Hemaspaandra, Christopher M. Homan, Sven Kosub, Klaus W. Wagner

Articles

Given a p-order A over a universe of strings (i.e., a transitive, reflexive, antisymmetric relation such that if (x, y) ∈ A then |x| is polynomially bounded by |y|), an interval size function of A returns, for each string x in the universe, the number of strings in the interval between strings b(x) and t(x) (with respect to A), where b(x) and t(x) are functions that are polynomial-time computable in the length of x. By choosing sets of interval size functions based on feasibility requirements for their underlying p-orders, we obtain new characterizations of complexity classes. We prove that the …


Cosmological Constraints From The Sdss Luminous Red Galaxies, Max Tegmark, Daniel J. Eisenstein, Michael Strauss, David H. Weinberg, Michael R. Blanton, Joshua A. Frieman, Masataka Fukugita, James E. Gunn, Andrew J. S. Hamilton, Gillian R. Knapp, Robert C. Nichol, Jeremiah P. Ostriker, Nikhil Padmanabhan, Will J. Percival, David J. Schlegel, Donald P. Schneider, Roman Scoccimarro, Uroš Seljak, Hee-Jong Seo, Molly Swanson, Alexander S. Szalay, Michael S. Vogeley, Jaiyul Yoo, Idit Zehavi, Kevork Abazajian, Scott F. Anderson, James Annis, Neta A. Bahcall, Bruce Bassett, Andreas Berlind, John Brinkman, Tamás Budavari, Francisco Castander, Andrew Connolly, Istvan Csabai, Mamoru Doi, Douglas P. Finkbeiner, Bruce Gillespie, Karl Glazebrook, Gregory S. Hennessy, David W. Hogg, Željko Ivezić, Bhuvnesh Jain, David Johnston, Stephen Kent, Donald Q. Lamb, Brian C. Lee, Huan Lin, Jon Loveday, Robert H. Lupton, Jeffrey A. Munn, Kaike Pan, Changbom Park, John Peoples, Jeffrey R. Pier, Adrian Pope, Michael Richmond, Constance Rockosi, Ryan Scranton, Ravi K. Sheth, Albert Stebbins, Christopher Stoughton, István Szapudi, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York Dec 2006

Cosmological Constraints From The Sdss Luminous Red Galaxies, Max Tegmark, Daniel J. Eisenstein, Michael Strauss, David H. Weinberg, Michael R. Blanton, Joshua A. Frieman, Masataka Fukugita, James E. Gunn, Andrew J. S. Hamilton, Gillian R. Knapp, Robert C. Nichol, Jeremiah P. Ostriker, Nikhil Padmanabhan, Will J. Percival, David J. Schlegel, Donald P. Schneider, Roman Scoccimarro, Uroš Seljak, Hee-Jong Seo, Molly Swanson, Alexander S. Szalay, Michael S. Vogeley, Jaiyul Yoo, Idit Zehavi, Kevork Abazajian, Scott F. Anderson, James Annis, Neta A. Bahcall, Bruce Bassett, Andreas Berlind, John Brinkman, Tamás Budavari, Francisco Castander, Andrew Connolly, Istvan Csabai, Mamoru Doi, Douglas P. Finkbeiner, Bruce Gillespie, Karl Glazebrook, Gregory S. Hennessy, David W. Hogg, Željko Ivezić, Bhuvnesh Jain, David Johnston, Stephen Kent, Donald Q. Lamb, Brian C. Lee, Huan Lin, Jon Loveday, Robert H. Lupton, Jeffrey A. Munn, Kaike Pan, Changbom Park, John Peoples, Jeffrey R. Pier, Adrian Pope, Michael Richmond, Constance Rockosi, Ryan Scranton, Ravi K. Sheth, Albert Stebbins, Christopher Stoughton, István Szapudi, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York

Articles

We measure the large-scale real-space power spectrum P(k) using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from the Wilkinson Microwave Anisotropy Probe (WMAP). We employ a matrix-based power spectrum estimation method using Pseudo-Karhunen-Lo`eve eigenmodes, producing uncorrelated minimum-variance measurements in 20 k-bands of both the clustering power and its anisotropy due to redshift-space distortions, with narrow and well-behaved window functions in the range 0.01 h/Mpc < k < 0.2 h/Mpc. Results from the LRG and main galaxy samples are consistent, with the former providing higher signal-to-noise. Our results are robust to omitting angular and radial density fluctuations and are consistent between different parts of the sky. They provide a striking confirmation of the predicted large-scale CDM power spectrum. Combining only SDSS LRG and WMAP data places robust constraints on many cosmological parameters that complement prior analyses of multiple data sets. The LRGs provide independent cross-checks on m and the baryon fraction in good agreement with WMAP. Within the context of flat CDM models, our LRG measurements complementWMAP by sharpening the constraints on the matter density, the neutrino density and the tensor amplitude by about a factor of two, giving m = 0.24±0.02 (1 ), Pmν < 0.9 eV (95%) and r < 0.3 (95%). Baryon oscillations are clearly detected and provide a robust measurement of the comoving distance to the median survey redshift z = 0.35 independent of curvature and dark energy properties. Within the CDM framework, our power spectrum measurement improves the evidence for spatial flatness, sharpening the curvature constraint tot = 1.05±0.05 from WMAP alone to tot = 1.003±0.010. Assuming tot = 1, the equation of state parameter is constrained to w = −0.94±0.09, indicating the potential for more ambitious future LRG measurements to provide precision tests of the nature of dark energy. All these constraints are essentially independent of scales k > 0.1h/Mpc and associated nonlinear complications, yet agree well with more aggressive published analyses where nonlinear modeling is crucial.


The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote Dec 2006

The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote

Articles

We examine the correlation between globular cluster (GC) color and magnitude using HST/ACS imaging for a sample of 79 early-type galaxies (−21.7 < MB < −15.2 mag) with accurate surfacebrightness fluctuation distances from the ACS Virgo Cluster Survey. Using the KMM mixture modeling algorithm, we find a highly significant correlation, z ≡ d(g−z) dz = −0.037 ± 0.004, between color and magnitude for the subpopulation of blue GCs in the co-added GC color-magnitude diagram of the three brightest Virgo cluster galaxies (M49, M87 and M60). The sense of the correlation is such that brighter GCs are redder than their fainter counterparts. For the single GC systems of M87 and M60, we find similar correlations; M49 does not appear to show a significant trend. There is no correlation between (g − z) and Mz for GCs belonging to the red subpopulation. The correlation g ≡ d(g−z) dg for the blue subpopulation is much weaker than z. Using Monte Carlo simulations, we attribute this finding to the fact that the blue subpopulation in Mg extends to higher luminosities than does the red subpopulation, which biases the KMM fit results. The highly significant correlation between color and Mz, however, is a real effect: this conclusion is supported by biweight fits to the same color distributions. We identify two environmental dependencies which influence the derived color-magnitude relation: (1) the slope of the color-magnitude relation decreases in significance with decreasing galaxy luminosity, although it remains detectable over the full luminosity range of our sample; and (2) the slope is stronger for GC populations located at smaller galactocentric distances. These characteristics suggest that the observed trend is, at least partially, shaped by external agents. We examine several physical mechanisms that might give rise to the observed color-magnitude relation including: (1) presence of contaminants like super-clusters, stripped galactic nuclei, or ultra-compact dwarfs; (2) accretion of GCs from low-mass galaxies; (3) stochastic effects; (4) the capture of field stars by individual GCs; and (5) GC self-enrichment. Although none of these scenarios offers a fully satisfactory explanation of the observations, we conclude that self-enrichment and field-star capture, or a combination of these processes, offer the most promising means of explaining our observations.


Tass Mark Iv Photometric Survey Of The Northern Sky, Thomas Droege, Michael Richmond, Michael Sallman, Robert P. Creager Dec 2006

Tass Mark Iv Photometric Survey Of The Northern Sky, Thomas Droege, Michael Richmond, Michael Sallman, Robert P. Creager

Articles

The Amateur Sky Survey (TASS) is a loose confederation of amateur and professional astronomers. We describe the design and construction of our Mark IV systems, a set of wide-field telescopes with CCD cameras which take simultaneous images in the V and IC passbands. We explain our observational procedures and the pipeline which processes and reduces the images into lists of stellar positions and magnitudes. We have compiled a large database of measurements for stars in the northern celestial hemisphere with V -band magnitudes in the range 7 < V < 13. This paper describes data taken over the four-year period starting November, 2001. One of our results is a catalog of repeated measurements on the Johnson-Cousins system for over 4.3 million stars.


Geometry Of Minimal Flows, William Basener Dec 2006

Geometry Of Minimal Flows, William Basener

Articles

Our main result is that a minimal flow on a compact manifold is either topologically conjugate to a Riemannian flow or every parametrization of φ is nowhere equicontinuous, defined as follows. A flow is Riemannian if given any points x, y ∈ M , the value of d(φt (x), φt (y)) is independent of t ∈ R . A flow is nowhere equicontinuous if there exists an


Contribution Of Stellar Tidal Disruptions To The X-Ray Luminosity Function Of Active Galaxies, Miloš Milosavljević, David Merritt, Luis C. Ho Nov 2006

Contribution Of Stellar Tidal Disruptions To The X-Ray Luminosity Function Of Active Galaxies, Miloš Milosavljević, David Merritt, Luis C. Ho

Articles

The luminosity function of active galactic nuclei has been measured down to luminosities ∼ 1042 ergs s-1 in the soft and hard X-rays. Some fraction of this activity is associated with the accretion of the material liberated by the tidal disruption of stars by massive black holes. We estimate the contribution to the X-ray luminosity function from the tidal disruption process. While the contribution depends on a number poorly known parameters, it appears that it can account for the majority of X-ray selected AGN with soft or hard Xray luminosities . 1043 - 1044 ergs s-1. If this is correct, …


Spectral Adaptation: A Reason To Use The Wavenumber Scale, Mark D. Fairchild Nov 2006

Spectral Adaptation: A Reason To Use The Wavenumber Scale, Mark D. Fairchild

Presentations and other scholarship

Chromatic adaptation refers to the ability of the human visual system to adjust to the color of the illumination, or other prevailing stimuli, such that perceived object colors vary far less with changes in illumination than would be expected from simple radiometry or colorimetry. Models of chromatic adaptation are generally formulated as extensions of the von Kries hypothesis of some sort of independent gain control mechanisms operating on the three types of cone signals. This paper introduces a new way to model the phenomenon with no requirement for the first stage chromatic processing. This model is referred to as a …


Alloy, Software Engineering, And Undergraduate Education, Michael J. Lutz Nov 2006

Alloy, Software Engineering, And Undergraduate Education, Michael J. Lutz

Presentations and other scholarship

RIT's undergraduate software engineering program has a strong emphasis on design, including formal mathematical modeling. However students (and professional software engineers) are skeptical about the use of mathematical models in their day-to-day work. Alloy has proven to be successful in addressing some of this skepticism, but further work is needed to make formal modeling a normin software development.


There Is No 2-(22,8,4) Block Design, Richard Bilous, Clement W.H. Lam, Larry H. Thiel, Ben P.C. Li, G.H. John Van Rees, Stanislaw P. Radziszowski, Wolfgang H. Holzmann, Hadi Kharaghani Oct 2006

There Is No 2-(22,8,4) Block Design, Richard Bilous, Clement W.H. Lam, Larry H. Thiel, Ben P.C. Li, G.H. John Van Rees, Stanislaw P. Radziszowski, Wolfgang H. Holzmann, Hadi Kharaghani

Articles

In this paper we show that a 2-(22, 8, 4) design does not exist. This result was obtained by a computer search.


A Nexus Of Education, Inspiration, Research And Play, Andrew Phelps Oct 2006

A Nexus Of Education, Inspiration, Research And Play, Andrew Phelps

Presentations and other scholarship

No abstract provided.


Trends In The Globular Cluster Luminosity Function Of Early-Type Galaxies, Andrés Jordán, Dean E. Mclaughlin, Patrick Côté, David Merritt, Et Al. Oct 2006

Trends In The Globular Cluster Luminosity Function Of Early-Type Galaxies, Andrés Jordán, Dean E. Mclaughlin, Patrick Côté, David Merritt, Et Al.

Articles

We present results from a study of the globular cluster luminosity function (GCLF) in a sample of 89 earlytype galaxies observed as part of the ACS Virgo Cluster Survey. Using a Gaussian parametrization of the GCLF, we find a highly significant correlation between the GCLF dispersion, , and the galaxy luminosity, MB,gal, in the sense that the GC systems in fainter galaxies have narrower luminosity functions. The GCLF dispersions in the Milky Way and M31 are fully consistent with this trend, implying that the correlation between sigma and galaxy luminosity is more fundamental than older suggestions that GCLF shape is …


Effect Of Nanostructure On The Thermal Oxidation Of Atomized Iron, Mohit Kumar, Naveen Rawat, Ksv Santhanam Oct 2006

Effect Of Nanostructure On The Thermal Oxidation Of Atomized Iron, Mohit Kumar, Naveen Rawat, Ksv Santhanam

Presentations and other scholarship

The effect of nanostructure on the thermal oxidation of atomized iron has been investigated. Above 500oC atomized iron is oxidized in the presence of air. However, when iron is compacted with multiwalled carbon nanotubes (MWCNT) this oxidation is shifted by more than 100oC. Iron is protected by the nanostructure environment A large number of compositions of atomic ratios of iron and MWCNT have been examined in this study to understand the effect in detail. The effect of nanostructure in the thermal oxidation of iron is interpreted as due to iron atom experiencing extensive overlap and confinement effect causing spin transfer. …


Evaluating Threat Assessment For Multi-Stage Cyber Attacks, Shanchieh Jay Yang, Jared Holsopple, Moises Sudit Oct 2006

Evaluating Threat Assessment For Multi-Stage Cyber Attacks, Shanchieh Jay Yang, Jared Holsopple, Moises Sudit

Presentations and other scholarship

Current practices to defend against cyber attacks are typically reactive yet passive. Recent research work has been proposed to proactively predict hacker's target entities in the early stage of the attack. With prediction, there comes false alarms and missed attacks. Very little has been reported on how to evaluate a threat assessment algorithm, especially for cyber security. Because of the variety and the constantly changing nature of hacker behavior and network vulnerabilities, a cyber threat assessment algorithm is, perhaps more susceptible that for other application domains. This work sets forth the issues on evaluating cyber threat assessment algorithms, and discusses …


A Hybrid Thermal Video And Ftir Spectrometer System For Rapidly Locating And Characterizing Gas Leaks, David J. Williams, Winthrop Wadsworth, Carl Salvaggio, David W. Messinger Sep 2006

A Hybrid Thermal Video And Ftir Spectrometer System For Rapidly Locating And Characterizing Gas Leaks, David J. Williams, Winthrop Wadsworth, Carl Salvaggio, David W. Messinger

Articles

Undiscovered gas leaks, known as fugitive emissions, in chemical plants and refinery operations can impact regional air quality and present a loss of product for industry. Surveying a facility for potential gas leaks can be a daunting task. Industrial leak detection and repair programs can be expensive to administer. An efficient, accurate and cost effective method for detecting and quantifying gas leaks would both save industries money by identifying production losses and improve regional air quality. Specialized thermal video systems have proven effective in rapidly locating gas leaks. These systems, however, do not have the spectral resolution for compound identification. …


Small Ramsey Numbers, Stanislaw Radziszowski Aug 2006

Small Ramsey Numbers, Stanislaw Radziszowski

Articles

We present data which, to the best of our knowledge, includes all known nontrivial values and bounds for specific graph, hypergraph and multicolor Ramsey numbers, where the avoided graphs are complete or complete without one edge. Many results pertaining to other more studied cases are also presented. We give references to all cited bounds and values, as well as to previous similar compilations. We do not attempt complete coverage of asymptotic behavior of Ramsey numbers, but concentrate on their specific values.


Transverse Disks, Symbolic Dynamics, Homology Direction Bectors, And Thurston-Nielson Theory, William Basener Aug 2006

Transverse Disks, Symbolic Dynamics, Homology Direction Bectors, And Thurston-Nielson Theory, William Basener

Articles

We review some properties of transverse disks and use symbolic dynamics to determine rotation vectors from the return map to a transverse disk. We also prove connections between the symbolic dynamics and Nielson equivalence of orbits.


Minimal Rankings And The A-Rank Number Of A Path, Victor Kostyuk, Darren Narayan, Victoria Shults Jul 2006

Minimal Rankings And The A-Rank Number Of A Path, Victor Kostyuk, Darren Narayan, Victoria Shults

Articles

Given a graph G, a function f:V(G)→ {1,2,…,k} is a k-ranking of G if f(u)=f(v) implies every u-v path contains a vertex w such that f(w)>f(u). A k-ranking is minimal if the reduction of any label greater than 1 violates the described ranking property. The arank number of a graph, denoted ψr(G), is the largest k such that G has a minimal k-ranking. We present new results involving minimal k-rankings of paths. In particular, we determine ψr(Pn), a problem posed by Laskar and Pillone in 2000 (Refer to PDF file for exact formulas).


Achromatic Optical Vortex Lens, Grover Jr Swartzlander Jul 2006

Achromatic Optical Vortex Lens, Grover Jr Swartzlander

Articles

A vortex lens is a useful optical device having applications ranging from astronomy to microscopy. Current vortex masks operate across a narrow bandwidth. Two design schemes are proposed for creating a vortex across a bandwidth exceeding 100 nm in the visible region of the spectrum.


Exploring The Career And Family Orientations Of Entrepreneurs: The Impact Of Gender And Dependent Status, Richard Demartino, Robert Barbato, Paul H. Jacques Jul 2006

Exploring The Career And Family Orientations Of Entrepreneurs: The Impact Of Gender And Dependent Status, Richard Demartino, Robert Barbato, Paul H. Jacques

Presentations and other scholarship

This study explores the career/achievement and family orientations of entrepreneurs - specifically the impact of sex and dependent child status. While a growing body of research has explored the similarities and uniqueness of women, none have explicitly analyzed entrepreneurs employing a career/achievement and family framework. Additionally, no studies have sought to explore the career/achievement and family orientations of female entrepreneurs with female non-entrepreneurs of similar backgrounds. Consequently, this research explores and compares the career/achievement and family orientations of female entrepreneurs with a group of female non-entrepreneurs with similar educational levels, ages, and work experience. It also compares the orientations of …


Modeling The Spectral Effects Of Water And Soil As Surface Contaminants In A High Resolution Optical Image Simulation, Kristin Strackerjan, Lon Smith, John Kerekes Jul 2006

Modeling The Spectral Effects Of Water And Soil As Surface Contaminants In A High Resolution Optical Image Simulation, Kristin Strackerjan, Lon Smith, John Kerekes

Articles

The primary interest of this research is to introduce selected environmental effects into RIT’s Digital Imaging and Remote Sensing Image Generation (DIRSIG) Model. DIRSIG is capable of producing high resolution images (meter scale) using Computer Aided Design models (CAD) of buildings, vehicles, trees, etc. across the full optical spectrum (0.35-25μm). Currently, these objects are modeled in a pristine manner and there is no option to simulate them after exposure to environmental effects. Ideally, we would like to subject a given material to these environmental effects and then accurately model the modified reflected or emitted spectrum. As a first step, we …


A Survey Of Kiloparsec-Scale Radio Outflows In Radio-Quiet Active Galactic Nuclei, Jack F. Gallimore, David Axon, Christopher P. O'Dea, Stefi A. Baum, Alan Pedlar Jun 2006

A Survey Of Kiloparsec-Scale Radio Outflows In Radio-Quiet Active Galactic Nuclei, Jack F. Gallimore, David Axon, Christopher P. O'Dea, Stefi A. Baum, Alan Pedlar

Articles

Seyfert galaxies commonly host compact jets spanning 10—100 pc scales, but larger structures are resolved out in long baseline, aperture synthesis surveys. Previous, targeted studies showed that kiloparsec-scale radio structures (KSRs) may be a common feature of Seyfert and LINER galaxies, and the origin of KSRs may be starburst or AGN. We report a new Very Large Array (VLA) survey of a complete sample of Seyfert and LINER galaxies. Out of all of the surveyed radio-quiet sources, we find that 44% (19 / 43) show extended radio structures at least 1 kpc in total extent that do not match the …


Using Hdr Display Technology And Color Appearance Modeling To Create Display Color Gamuts That Exceed The Spectrum Locus, Rodney Heckaman, Mark Fairchild Jun 2006

Using Hdr Display Technology And Color Appearance Modeling To Create Display Color Gamuts That Exceed The Spectrum Locus, Rodney Heckaman, Mark Fairchild

Presentations and other scholarship

No abstract provided.


Optical Polarimetry Of The Jets Of Nearby Radio Galaxies. I. The Data, Eric Perlman, Alex Padgett, Markos Georganopoulos, Christopher P. O'Dea, Stefi A. Baum, Et Al. Jun 2006

Optical Polarimetry Of The Jets Of Nearby Radio Galaxies. I. The Data, Eric Perlman, Alex Padgett, Markos Georganopoulos, Christopher P. O'Dea, Stefi A. Baum, Et Al.

Articles

In this paper, the first in a series, we present an overview of new Hubble Space Telescope (HST) imaging polarimetry of six nearby radio galaxies (3C 15, 3C 66B, 3C 78, 3C 264, 3C 346, and 3C 371) with optical jets. These observations triple the number of extragalactic jets with subarcsecond-resolution optical polarimetry. We discuss the polarization characteristics of each jet and, as our Stokes I images also represent by far the deepest optical images yet obtained of each of these jets, we also discuss the morphology in total flux of each jet in detail. We find evidence of high …


On The Economics Of Sustainability, Jeffrey Wagner Jun 2006

On The Economics Of Sustainability, Jeffrey Wagner

Articles

Journal Home Page: http://www.elsevier.com/wps/find/journaldescription.cws_home/503305/description#description The purpose of this paper is to work toward reconciliation of the neoclassical consumer choice axiom that "more is better" and the ecological concern that "more is not sustainable." The key is to divide the desired "more" into its rival and nonrival components, for it is the consumption of rival goods (such as plastic) that strains the ecosystem. In contrast, the consumption of nonrival goods (such as bird-watching) leaves little to no footprint . While sustain ability can be enhanced through changing preferences, a menu of taxes, subsidies and/or vouchers can also motivate greater nonrival consumption …


Automatic Tie Point Selection Using Laplacian Of Gaussian (Log) Spatial Filtering, Seth Weith-Glushko, Karl Walli, Carl Salvaggio Jun 2006

Automatic Tie Point Selection Using Laplacian Of Gaussian (Log) Spatial Filtering, Seth Weith-Glushko, Karl Walli, Carl Salvaggio

Articles

This research examines the utility of an automated image registration technique that utilizes the Laplacian of Gaussian filter to extract semi-invariant ground control points, the use of matrix transformations for efficient management of affine image relationships, and wavelet theory for multi-resolution analysis. Additionally, advances in both composite and predictive transformations will be covered. Results will be presented that demonstrate the utility of these techniques for processing large data sets such as HyVista Corporation’s HyMap sensor. Automation techniques will be highlighted, demonstrating the strengths and weaknesses when applied to images with high degrees of parallax, cloud-cover, and other types of temporal …


Mass Deficits, Stalling Radii, And The Merger Histories Of Elliptical Galaxies, David Merritt May 2006

Mass Deficits, Stalling Radii, And The Merger Histories Of Elliptical Galaxies, David Merritt

Articles

A binary supermassive black hole leaves an imprint on a galactic nucleus in the form of a “mass deficit,” a decrease in the mass of the nucleus due to ejection of stars by the binary. The magnitude of the mass deficit is in principle related to the galaxy’s merger history, but the relation has never been quantified. Here, highaccuracy N-body simulations are used to calibrate this relation. Mass deficits are shown to be Mde f ≈ 0.5M12, with M12 the total mass of the binary; the coefficient in this relation depends only weakly on M2/M1 or on the galaxy’s pre-existing …


Service-Oriented Architecture: Technology Selection And Strategic It Management, Brian Payne, James Baroody May 2006

Service-Oriented Architecture: Technology Selection And Strategic It Management, Brian Payne, James Baroody

Presentations and other scholarship

This paper examines the strategic decision making process of managing IT infrastructures. In particular, this paper proposes a methodology that can be employed in making a company's decision to implement a Service Oriented Architecture (SOA). SOA forces us, for the first time, to analyze and truly examine our IT operations through business--not technical--perspectives (DATZ, 2004). Accordingly, the decision to embrace or not to embrace SOA and in what capacity, combines quantitative and qualitative factors from both business and technical perspectives. Therefore, it is not possible to provide a purely objective measure by which the decision to embrace SOA can be …


Semi-Automated Dirsig Scene Modeling From 3d Lidar And Passive Imaging Sources, Steve R. Lach, Scott D. Brown, John P. Kerekes May 2006

Semi-Automated Dirsig Scene Modeling From 3d Lidar And Passive Imaging Sources, Steve R. Lach, Scott D. Brown, John P. Kerekes

Presentations and other scholarship

The Digital Imaging and Remote Sensing Image Generation (DIRSIG) model is an established, first-principles based scene simulation tool that produces synthetic multispectral and hyperspectral images from the visible to long wave infrared (0.4 to 20 microns). Over the last few years, significant enhancements such as spectral polarimetric and active Light Detection and Ranging (LIDAR) models have also been incorporated into the software, providing an extremely powerful tool for algorithm testing and sensor evaluation. However, the extensive time required to create large-scale scenes has limited DIRSIG’s ability to generate scenes “on demand.” To date, scene generation has been a laborious, time-intensive …


A Fundamental Relation Between Compact Stellar Nuclei, Supermassive Black Holes, And Their Host Galaxies, Laura Ferrarese, Patrick Côté, Elena Dalla Bontà, David Merritt, Et Al. May 2006

A Fundamental Relation Between Compact Stellar Nuclei, Supermassive Black Holes, And Their Host Galaxies, Laura Ferrarese, Patrick Côté, Elena Dalla Bontà, David Merritt, Et Al.

Articles

Imaging surveys with the Hubble Space Telescope (HST) have shown that 50–80% of low- and intermediate-luminosity galaxies contain a compact stellar nucleus at their center, regardless of host galaxy morphological type. We combine HST imaging for early-type galaxies from the ACS Virgo Cluster Survey with ground-based long-slit spectra from KPNO to show that the masses of compact stellar nuclei in Virgo Cluster galaxies obey a tight correlation with the masses of the host galaxies. The same correlation is obeyed by the supermassive black holes (SBHs) found in predominantly massive galaxies. The compact stellar nuclei in the Local Group galaxies M33 …