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Full-Text Articles in Physical Sciences and Mathematics

Reduced Row Echelon Form And Non-Linear Approximation For Subspace Segmentation And High-Dimensional Data Clustering, Akram Aldroubi, Ali Sekmen Dec 2013

Reduced Row Echelon Form And Non-Linear Approximation For Subspace Segmentation And High-Dimensional Data Clustering, Akram Aldroubi, Ali Sekmen

Computer Science Faculty Research

Given a set of data W={w1,…,wN}∈RD drawn from a union of subspaces, we focus on determining a nonlinear model of the form U=⋃i∈ISi, where {Si⊂RD}i∈I is a set of subspaces, that is nearest to W. The model is then used to classify W into clusters. Our approach is based on the binary reduced row echelon form of data matrix, combined with an iterative scheme based on a non-linear approximation method. We prove that, in absence of noise, our approach can find the number of subspaces, their dimensions, and an orthonormal basis for each subspace Si. We provide a comprehensive analysis …


Multiperiodicity, Modulations And Flip-Flops In Variable Star Light Curves Ii. Analysis Of Ii Pegasus Photometry During 1979–2010, Marjaana Lindborg, Maarit J. Mantere, Nigul Olspert, Jaan Pelt, Thomas Hackman, Gregory W. Henry, Lauri Jetsu, Klaus G. Strassmeier Nov 2013

Multiperiodicity, Modulations And Flip-Flops In Variable Star Light Curves Ii. Analysis Of Ii Pegasus Photometry During 1979–2010, Marjaana Lindborg, Maarit J. Mantere, Nigul Olspert, Jaan Pelt, Thomas Hackman, Gregory W. Henry, Lauri Jetsu, Klaus G. Strassmeier

Information Systems and Engineering Management Research Publications

Aims. According to previously published Doppler images of the magnetically active primary giant component of the RS CVn binary II Peg, the surface of the star was dominated by one single active longitude that was clearly drifting in the rotational frame of the binary system during 1994-2002; later imaging for 2004–2010, however, showed decreased and chaotic spot activity, with no signs of the drift pattern. Here we set out to investigate from a more extensive photometric dataset whether this drift is a persistent phenomenon, in which case it could be caused either by an azimuthal dynamo wave or be an …


Estimating Loop Length From Cryoem Images At Medium Resolutions, Andrew Mcknight, Dong Si, Kamal Al Nasr, Andrey Chernikov, Nikos Chrisochoides, Jing He Nov 2013

Estimating Loop Length From Cryoem Images At Medium Resolutions, Andrew Mcknight, Dong Si, Kamal Al Nasr, Andrey Chernikov, Nikos Chrisochoides, Jing He

Computer Science Faculty Research

Background

De novo protein modeling approaches utilize 3-dimensional (3D) images derived from electron cryomicroscopy (CryoEM) experiments. The skeleton connecting two secondary structures such as α-helices represent the loop in the 3D image. The accuracy of the skeleton and of the detected secondary structures are critical in De novo modeling. It is important to measure the length along the skeleton accurately since the length can be used as a constraint in modeling the protein.

Results

We have developed a novel computational geometric approach to derive a simplified curve in order to estimate the loop length along the skeleton. The method …


Absolute Properties Of The Eclipsing Binary Vv Corvi, Francis C. Fekel, Gregory W. Henry, James R. Sowell Oct 2013

Absolute Properties Of The Eclipsing Binary Vv Corvi, Francis C. Fekel, Gregory W. Henry, James R. Sowell

Information Systems and Engineering Management Research Publications

We have obtained red-wavelength spectroscopy and Johnson B and V differential photoelectric photometry of the eclipsing binary VV Crv = HR 4821. The system is the secondary of the common proper motion double star ADS 8627, which has a separation of 52. VV Crv has an orbital period of 3.144536 days and a low but non-zero eccentricity of 0.085. With the Wilson–Devinney program we have determined a simultaneous solution of our spectroscopic and photometric observations. Those orbital elements produce masses of M1 = 1.978 ± 0.010 M and M2 = 1.513 ± 0.008 M, and …


Multimedia Data Fusion, Shangbo Zhou, Henry Leung, Fenghui Yao Oct 2013

Multimedia Data Fusion, Shangbo Zhou, Henry Leung, Fenghui Yao

Computer Science Faculty Research

Multimedia data is widely used in the world such as image, video, text, and audio. For obtaining better sensing performance, research on multimedia data fusion (MDF) is active and extensive around the world. In medical systems, a body part could be imaged with different sensors such as computed tomography and magnetic resonance imaging. In video surveillance, the interest is in the identification, recognition, and tracking of people by numerous cameras. All of these cases illustrate the importance of MDF in real-life applications. A number of mathematical methods have been researched in MDF such as statistics, fuzzy mathematical, stochastic differential theory, …


Hubble Space Telescope Hot Jupiter Transmission Spectral Survey: A Detection Of Na And Strong Optical Absorption In Hat-P-1b, Nikolay Nikolov, David K. Sing, Frederic Pont, Adam S. Burrows, Jonathan J. Fortney, Gilda E. Ballester, Thomas M. Evans, Catherine M. Huitson, Hannah R. Wakeford, Paul A. Wilson, Suzanne Aigrain, Drake Deming, Neale P. Gibson, Gregory W. Henry, Heather Knutson, Alain Lecavelier Des Etangs, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle Oct 2013

Hubble Space Telescope Hot Jupiter Transmission Spectral Survey: A Detection Of Na And Strong Optical Absorption In Hat-P-1b, Nikolay Nikolov, David K. Sing, Frederic Pont, Adam S. Burrows, Jonathan J. Fortney, Gilda E. Ballester, Thomas M. Evans, Catherine M. Huitson, Hannah R. Wakeford, Paul A. Wilson, Suzanne Aigrain, Drake Deming, Neale P. Gibson, Gregory W. Henry, Heather Knutson, Alain Lecavelier Des Etangs, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle

Information Systems and Engineering Management Research Publications

We present an optical to near-infrared transmission spectrum of the hot Jupiter HAT-P-1b, based on Hubble Space Telescope observations, covering the spectral regime from 0.29 to 1.027 μm with Space Telescope Imaging Spectrograph (STIS), which is coupled with a recent Wide Field Camera 3 (WFC3) transit (1.087 to 1.687 μm). We derive refined physical parameters of the HAT-P-1 system, including an improved orbital ephemeris. The transmission spectrum shows a strong absorption signature shortward of 0.55 μm, with a strong blueward slope into the near-ultraviolet. We detect atmospheric sodium absorption at a 3.3σ significance level, but find no evidence for the …


Hst Hot-Jupiter Transmission Spectral Survey: Evidence For Aerosols And Lack Of Tio In The Atmosphere Of Wasp-12b, David K. Sing, Alain Lecavelier Des Etangs, Jonathan J. Fortney, Adam Burrows, Frederic Pont, Hannah R. Wakeford, Gilda E. Ballester, Nikolay Nikolov, Gregory W. Henry, Suzanne Aigrain, Drake Deming, Thomas M. Evans, Neale P. Gibson, Catherine M. Huitson, Heather Knutson, Adam P. Showman, Alfred Vidal-Madjar, Paul A. Wilson, Michael H. Williamson, Kevin J. Zahnle Oct 2013

Hst Hot-Jupiter Transmission Spectral Survey: Evidence For Aerosols And Lack Of Tio In The Atmosphere Of Wasp-12b, David K. Sing, Alain Lecavelier Des Etangs, Jonathan J. Fortney, Adam Burrows, Frederic Pont, Hannah R. Wakeford, Gilda E. Ballester, Nikolay Nikolov, Gregory W. Henry, Suzanne Aigrain, Drake Deming, Thomas M. Evans, Neale P. Gibson, Catherine M. Huitson, Heather Knutson, Adam P. Showman, Alfred Vidal-Madjar, Paul A. Wilson, Michael H. Williamson, Kevin J. Zahnle

Information Systems and Engineering Management Research Publications

We present Hubble Space Telescope (HST) optical transmission spectra of the transiting hot-Jupiter WASP-12b, taken with the Space Telescope Imaging Spectrograph instrument. The resulting spectra cover the range 2900–10 300 Å which we combined with archival Wide Field Camera 3 spectra and Spitzer photometry to cover the full optical to infrared wavelength regions. With high spatial resolution, we are able to resolve WASP-12A's stellar companion in both our images and spectra, revealing that the companion is in fact a close binary M0V pair, with the three stars forming a triple-star configuration. We derive refined physical parameters of the WASP-12 system, …


New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Viii. Hr 1528, Hr 6993, 2 Sagittae, And 18 Vulpeculae, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson Oct 2013

New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Viii. Hr 1528, Hr 6993, 2 Sagittae, And 18 Vulpeculae, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson

Information Systems and Engineering Management Research Publications

Improved orbital elements for four A-star double-lined spectroscopic binaries have been determined with numerous new radial velocities. Three of the four systems, HR 1528, 2 Sge, and 18 Vul, have moderately short orbital periods of 7.05, 7.39, and 9.31 days, respectively, and also have circular or nearly circular orbits. Only HR 6993 with a period of 14.68 days has a significantly eccentric orbit. The close visual companion of 2 Sge has been detected spectroscopically, and its velocity measured. The orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) of the …


Hst Hot Jupiter Transmission Spectral Survey: Detection Of Water In Hat-P-1b From Wfc3 Near-Ir Spatial Scan Observations, Hannah R. Wakeford, David K. Sing, Drake Deming, Neale P. Gibson, Jonathan J. Fortney, Adam Burrows, Gilda E. Ballester, Nikolay Nikolov, Suzanne Aigrain, Gregory W. Henry, Heather Knutson, Alain Lecavelier Des Etangs, Frederic Pont, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle Sep 2013

Hst Hot Jupiter Transmission Spectral Survey: Detection Of Water In Hat-P-1b From Wfc3 Near-Ir Spatial Scan Observations, Hannah R. Wakeford, David K. Sing, Drake Deming, Neale P. Gibson, Jonathan J. Fortney, Adam Burrows, Gilda E. Ballester, Nikolay Nikolov, Suzanne Aigrain, Gregory W. Henry, Heather Knutson, Alain Lecavelier Des Etangs, Frederic Pont, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle

Information Systems and Engineering Management Research Publications

We present Hubble Space Telescope near-infrared transmission spectroscopy of the transiting hot-Jupiter HAT-P-1b. We observed one transit with Wide Field Camera 3 using the G141 low-resolution grism to cover the wavelength range 1.087–1.678 μm. These time series observations were taken with the newly available spatial-scan mode that increases the duty cycle by nearly a factor of 2, thus improving the resulting photometric precision of the data. We measure a planet-to-star radius ratio of Rp/R* = 0.117 09 ± 0.000 38 in the white light curve with the centre of transit occurring at 245 6114.345 ± 0.000 133 (JD). We achieve …


Astrometric Mass Ratios For Three Spectroscopic Binaries, Johannes Sahlmann, Francis C. Fekel Aug 2013

Astrometric Mass Ratios For Three Spectroscopic Binaries, Johannes Sahlmann, Francis C. Fekel

Information Systems and Engineering Management Research Publications

The orbits of five single-lined spectroscopic binaries have recently been determined. We now use astrometric measurements that were collected with the HIPPARCOS satellite to constrain the systems’ mass ratios and secondary masses. The barycentric astrometric orbits of three binary systems, HD 140667, HD 158222, and HD 217924, are fully determined and precise estimates of their mass ratios are obtained. Follow-up of these systems with infrared spectroscopy could yield model-independent dynamical masses for all components.


An Hst Optical-To-Near-Ir Transmission Spectrum Of The Hot Jupiter Wasp-19b: Detection Of Atmospheric Water And Likely Absence Of Tio, Catherine M. Huitson, David K. Sing, Frederic Pont, Jonathan J. Fortney, Adam Burrows, Paul A. Wilson, Gilda E. Ballester, Nikolay Nikolov, Neale P. Gibson, Drake Deming, Suzanne Aigrain, Thomas M. Evans, Gregory W. Henry, Alain Lecavelier Des Etangs, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle Jul 2013

An Hst Optical-To-Near-Ir Transmission Spectrum Of The Hot Jupiter Wasp-19b: Detection Of Atmospheric Water And Likely Absence Of Tio, Catherine M. Huitson, David K. Sing, Frederic Pont, Jonathan J. Fortney, Adam Burrows, Paul A. Wilson, Gilda E. Ballester, Nikolay Nikolov, Neale P. Gibson, Drake Deming, Suzanne Aigrain, Thomas M. Evans, Gregory W. Henry, Alain Lecavelier Des Etangs, Adam P. Showman, Alfred Vidal-Madjar, Kevin J. Zahnle

Information Systems and Engineering Management Research Publications

We measure the transmission spectrum of WASP-19b from three transits using low-resolution optical spectroscopy from the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS). The STIS spectra cover a wavelength range of 0.29–1.03 μm, with resolving power R = 500. The optical data are combined with archival near-infrared data from the HST Wide Field Camera 3 (WFC3) G141 grism, covering the wavelength range from 1.087 to 1.687 μm, with resolving power R = 130. We reach signal-to-noise levels between 3000 and 11 000 in 0.1 μm bins when measuring the transmission spectra from 0.53–1.687 μm. WASP-19 is known to …


Responses Of Soil Respiration And Its Temperature/Moisture Sensitivity To Precipitation In Three Subtropical Forests In Southern China, H. Jiang, Qi Deng, Guoyi Zhou, Dafeng Hui, Deqiang Zhang, S. Liu, Guowei Chu, J. Li Jun 2013

Responses Of Soil Respiration And Its Temperature/Moisture Sensitivity To Precipitation In Three Subtropical Forests In Southern China, H. Jiang, Qi Deng, Guoyi Zhou, Dafeng Hui, Deqiang Zhang, S. Liu, Guowei Chu, J. Li

Biology Faculty Research

Both long-term observation data and model simulations suggest an increasing chance of serious drought in the dry season and extreme flood in the wet season in southern China, yet little is known about how changes in precipitation pattern will affect soil respiration in the region. We conducted a field experiment to study the responses of soil respiration to precipitation manipulations – precipitation exclusion to mimic drought, double precipitation to simulate flood, and ambient precipitation as control (abbr. EP, DP and AP, respectively) – in three subtropical forests in southern China. The three forest sites include Masson pine forest (PF), coniferous …


Infrared Spectroscopy Of Symbiotic Stars. Ix. D-Type Symbiotic Novae, Kenneth H. Hinkle, Francis C. Fekel, Richard R. Joyce, Peter R. Wood May 2013

Infrared Spectroscopy Of Symbiotic Stars. Ix. D-Type Symbiotic Novae, Kenneth H. Hinkle, Francis C. Fekel, Richard R. Joyce, Peter R. Wood

Information Systems and Engineering Management Research Publications

Time-series spectra of the near-infrared 1.6 μm region have been obtained for five of the six known D-type symbiotic novae. The spectra map the pulsation kinematics of the Mira component in the Mira–white dwarf binary system and provide the center-of-mass velocity for the Mira. No orbital motion is detected in agreement with previous estimates of orbital periods ≳100 yr and semimajor axes ∼50 AU. The 1–5 μm spectra of the Miras show line weakening during dust obscuration events. This results from scattering and continuum emission by 1000 K dust. In the heavily obscured HM Sge system the 4.6 μm CO …


The Prevalence Of Dust On The Exoplanet Hd 189733b From Hubble And Spitzer Observations, Frederic Pont, David K. Sing, Neale P. Gibson, Suzanne Aigrain, Gregory W. Henry, Nawal Husnoo May 2013

The Prevalence Of Dust On The Exoplanet Hd 189733b From Hubble And Spitzer Observations, Frederic Pont, David K. Sing, Neale P. Gibson, Suzanne Aigrain, Gregory W. Henry, Nawal Husnoo

Information Systems and Engineering Management Research Publications

The hot Jupiter HD 189733b is the most extensively observed exoplanet. Its atmosphere has been detected and characterized in transmission and eclipse spectroscopy, and its phase curve measured at several wavelengths. This paper brings together the results of our campaign to obtain the complete transmission spectrum of the atmosphere of this planet from UV to infrared with the Hubble Space Telescope, using the STIS, ACS and WFC3 instruments. We provide a new tabulation of the transmission spectrum across the entire visible and infrared range. The radius ratio in each wavelength band was re-derived, where necessary, to ensure a consistent treatment …


Host Star Properties And Transit Exclusion For The Hd 38529 Planetary System, Gregory W. Henry, Stephen R. Kane, Sharon X. Wang, Jason T. Wright, Tabetha S. Boyajian, Kaspar Von Braun, David R. Ciardi, Diana Dragomir, Chris D. Farrington, Debra A. Fischer, Natalie R. Hinkel, Andrew W. Howard, Eric Jensen, Gregory Laughlin, Suvrath Mahadevan, Genady Pilyavsky Apr 2013

Host Star Properties And Transit Exclusion For The Hd 38529 Planetary System, Gregory W. Henry, Stephen R. Kane, Sharon X. Wang, Jason T. Wright, Tabetha S. Boyajian, Kaspar Von Braun, David R. Ciardi, Diana Dragomir, Chris D. Farrington, Debra A. Fischer, Natalie R. Hinkel, Andrew W. Howard, Eric Jensen, Gregory Laughlin, Suvrath Mahadevan, Genady Pilyavsky

Information Systems and Engineering Management Research Publications

The transit signature of exoplanets provides an avenue through which characterization of exoplanetary properties may be undertaken, such as studies of mean density, structure, and atmospheric composition. The Transit Ephemeris Refinement and Monitoring Survey is a program to expand the catalog of transiting planets around bright host stars by refining the orbits of known planets discovered with the radial velocity technique. Here we present results for the HD 38529 system. We determine fundamental properties of the host star through direct interferometric measurements of the radius and through spectroscopic analysis. We provide new radial velocity measurements that are used to improve …


Using Photometry To Probe The Circumstellar Environment Of Δ Scorpii, Carol E. Jones, Paul A. Wiegert, Christopher Tycner, Gregory W. Henry, Richard P. Cyr, Robbie J. Halonen, Matthew W. Muterspaugh Apr 2013

Using Photometry To Probe The Circumstellar Environment Of Δ Scorpii, Carol E. Jones, Paul A. Wiegert, Christopher Tycner, Gregory W. Henry, Richard P. Cyr, Robbie J. Halonen, Matthew W. Muterspaugh

Information Systems and Engineering Management Research Publications

We acquired Johnson BV photometry of the binary Be disk system δ Scorpii during its 2009, 2010, 2011, and 2012 observing seasons and used it to probe the innermost regions of the disk. We found that several disk building events have occurred during this time, resulting in an overall brightening in the V band and reddening of the system. In addition to these long-term trends, we found cyclical variability in each observing season on timescales between 60 and 100 days. We were able to reproduce the changes in the magnitude and color of δ Sco using our theoretical models and …


Instrumental Music Ensemble At Tennessee State University: The Early Years (1912-1946), Reginald A. Mcdonald Apr 2013

Instrumental Music Ensemble At Tennessee State University: The Early Years (1912-1946), Reginald A. Mcdonald

The Journal of Tennessee State University

No abstract provided.


The Resilience Of One Tennessee State University Professor In Providing A Path To Excellence For Youths, Sean Daniels Apr 2013

The Resilience Of One Tennessee State University Professor In Providing A Path To Excellence For Youths, Sean Daniels

The Journal of Tennessee State University

No abstract provided.


The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, Francis C. Fekel, Samira Rajabi, Matthew W. Muterspaugh, Michael H. Williamson Mar 2013

The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, Francis C. Fekel, Samira Rajabi, Matthew W. Muterspaugh, Michael H. Williamson

Information Systems and Engineering Management Research Publications

We have determined spectroscopic orbits for five single-lined spectroscopic binaries, HD 100167, HD 135991, HD 140667, HD 158222, HD 217924. Their periods range from 60.6 to 2403 days and the eccentricities from 0.20 to 0.84. Our spectral classes for the stars confirm that they are of solar type, F9–G5, and all are dwarfs. Their [Fe/H] abundances, determined spectroscopically, are close to the solar value and on average are 0.12 greater than abundances from a photometric calibration. Four of the five stars are rotating faster than their predicted pseudosynchronous rotational velocities.


The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, Francis C. Fekel, Michael H. Williamson, Michael Weber, Klaus G. Strassmeier, Dimitri Pourbaix Mar 2013

The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, Francis C. Fekel, Michael H. Williamson, Michael Weber, Klaus G. Strassmeier, Dimitri Pourbaix

Information Systems and Engineering Management Research Publications

We have determined an improved orbit for the bright, evolved, double lined binary γ Canis Minoris. The system has an orbital period of 389.31 days and an eccentricity of 0.2586. We have revised the secondary to primary mass ratio to 0.987. The spectral types of the primary and secondary are K4 III and K1: III, respectively, and the components have a V magnitude difference of 2.2. Orbital fits to the Hipparcos astrometry are not definitive, but they suggest an orbital inclination of ∼ 66°, which produces masses of 1.88 and 1.85 M⊙ for the components. A comparison with evolutionary tracks …


A Novel Algorithm For Validating Peptide Identification From A Shotgun Proteomics Search Engine, Ling Jian, Xinnan Niu, Zhonghang Xia, Parimal Samir, Chiranthani Sumanasekera, Zheng Mu, Jennifer L. Jennings, Kristen L. Hoek, Tara Allos, Leigh M. Howard, Kathryn M. Edwards, P. Anthony Weil, Andrew J. Link Feb 2013

A Novel Algorithm For Validating Peptide Identification From A Shotgun Proteomics Search Engine, Ling Jian, Xinnan Niu, Zhonghang Xia, Parimal Samir, Chiranthani Sumanasekera, Zheng Mu, Jennifer L. Jennings, Kristen L. Hoek, Tara Allos, Leigh M. Howard, Kathryn M. Edwards, P. Anthony Weil, Andrew J. Link

Chemistry Faculty Research

Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) has revolutionized the proteomics analysis of complexes, cells, and tissues. In a typical proteomic analysis, the tandem mass spectra from a LC–MS/MS experiment are assigned to a peptide by a search engine that compares the experimental MS/MS peptide data to theoretical peptide sequences in a protein database. The peptide spectra matches are then used to infer a list of identified proteins in the original sample. However, the search engines often fail to distinguish between correct and incorrect peptides assignments. In this study, we designed and implemented a novel algorithm called De-Noise to …


The Stellar Activity-Rotation Relationship, Nick J. Wright, Jeremy J. Drake, Eric E. Mamajek, Gregory W. Henry Feb 2013

The Stellar Activity-Rotation Relationship, Nick J. Wright, Jeremy J. Drake, Eric E. Mamajek, Gregory W. Henry

Information Systems and Engineering Management Research Publications

Using a new catalog of 824 solar and late-type stars with measured X-ray luminosities and rotation periods we have studied the relationship between rotation and stellar activity that is believed to be a probe of the underlying stellar dynamo. Using an unbiased subset of the sample we calculate the power law slope of the unsaturated regime of the activity-rotation relationship as LX/Lbol α Roβ, where β = –2.70 ± 0.13. Notably this is inconsistent with the canonical β = –2 slope to a confidence of 5σ are argues for an interface-type dynamo. Super-saturation is observed for the fastest rotators in …