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Related papers: Spectral ageing: a new age perspective

200 papers

Automated facial age assessment systems operate in either estimation mode - predicting age based on facial traits, or verification mode - confirming a claimed age. These systems support access control to age-restricted goods, services, and…

Computers and Society · Computer Science 2025-05-29 Richard Guest , Eva Lievens , Martin Sas , Elena Botoeva , Temitope Adeyemo , Valerie Verdoodt , Elora Fernandes , Chris Allgrove

Two frequency observations, mainly at 1.4 and 5 GHz from the VLA, have been used to study spectral variations along the lobes of some nearby low luminosity radio galaxies that constitute a representative sample selected from the B2…

Astrophysics · Physics 2007-05-23 P. Parma , M. Murgia , R. Morganti , A. Capetti , H. R. de Ruiter , R. Fanti

The physical properties of almost any kind of astronomical object can be derived by fitting synthetic spectra or photometry extracted from theoretical models to observational data. This process usually involves working with multiwavelength…

Various methods for age dating globular clusters in ellipticals are presented. We first present spectroscopy of individual globular clusters (feasible with the advent of the 10m-class telescopes), and the measurement of Balmer line indices.…

Astrophysics · Physics 2007-05-23 Markus Kissler-Patig

The high-frequency integrated spectra of Compact Steep Spectrum (CSS) sources show breaks with a moderate spectral steepening well fitted by continuous injection synchrotron spectra. In lobe-dominated CSS sources the radiative ages deduced…

Astrophysics · Physics 2009-10-31 M. Murgia , C. Fanti , R. Fanti , L. Gregorini , U. Klein , K. -H. Mack , M. Vigotti

The age of an individual star cannot be measured, only estimated through mostly model-dependent or empirical methods, and no single method works well for a broad range of stellar types or for a full range in age. This review presents a…

Solar and Stellar Astrophysics · Physics 2015-05-18 David R. Soderblom

Multifrequency observations with the GMRT and the VLA are used to determine the spectral breaks in consecutive strips along the lobes of a sample of selected giant radio sources (GRSs) in order to estimate their spectral ages. The maximum…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-05 C. Konar , D. J. Saikia , M. Jamrozy , J. Machalski

Motor age determination as a part of condition monitoring heavily employs vibration analysis. This study introduces a new method for such analysis, based on concepts of cepstrum and marginal Hilbert spectrum. This new method, named Berthil…

Data Analysis, Statistics and Probability · Physics 2017-05-29 Harun Siljak , Abdulhamit Subasi

Spectral imaging has recently gained traction for face recognition in biometric systems. We investigate the merits of spectral imaging for face recognition and the current challenges that hamper the widespread deployment of spectral sensors…

Computer Vision and Pattern Recognition · Computer Science 2020-01-06 Rumaisah Munir , Rizwan Ahmed Khan

Spectral imaging is an umbrella term for energy-resolved x-ray imaging in medicine. The technique makes use of the energy dependence of x-ray attenuation to either increase the contrast-to-noise ratio, or to provide quantitative image data…

Medical Physics · Physics 2021-01-05 Erik Fredenberg

We investigate the uncertainties in the synthetic integrated colors of simple stellar populations. Three types of uncertainties are from the stellar models, the population synthesis techniques, and from the spectral libraries. Despite some…

Astrophysics · Physics 2011-07-18 Sukyoung K. Yi

There are three independent techniques for determining the age of the universe: via cosmochronology of long-lived radioactive nuclei, via stellar modelling and population synthesis of the oldest stellar populations, and via the precision…

Astrophysics · Physics 2009-11-06 I. Ferreras , A. Melchiorri , J. Silk

Among the various methods used to age-date stars, methods based on stellar model predictions are widely used, for nearly all kind of stars in large ranges of masses, chemical compositions and evolutionary stages. The precision and accuracy…

Solar and Stellar Astrophysics · Physics 2015-06-23 Yveline Lebreton , Marie-Jo Goupil , J. Montalban

I consider ageing behaviour in two exactly solvable reaction-diffusion systems. Ageing exponents and scaling functions are determined. I discuss in particular a case in which the equality of two critical exponents, known from systems with…

Statistical Mechanics · Physics 2007-05-23 Florian Baumann

We describe the inter-dependence of four properties of classical double radio sources - spectral index, linear size, luminosity and redshift - from an extensive study based on spectroscopically-identified complete samples. We use these…

Astrophysics · Physics 2007-05-23 Katherine Blundell , Steve Rawlings , Chris Willott

Problems solved? Pulsar research must be considered - 35 years after the detection of pulsars - a mature science, where the basic questions have been raised and discussed. One would hope that many if not all generic and important problems…

Astrophysics · Physics 2007-05-23 W. Sieber

Dynamical ages of the opposite lobes determined {\sl independently} of each other suggest that their ratios are between $\sim$1.1 to $\sim$1.4. Demanding similar values of the jet power and the radio core density for the same GRS, we look…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-06 J. Machalski , M. Jamrozy , D. J. Saikia

We consider networked sources that generate update messages with a defined rate and we investigate the age of that information at the receiver. Typical applications are in cyber-physical systems that depend on timely sensor updates. We…

Networking and Internet Architecture · Computer Science 2022-01-26 Mahsa Noroozi , Markus Fidler

In this paper authors present a general methodology for age dependent reliability analysis of degrading or ageing systems, structures and components.The methodology is based on Bayesian methods and inference, its ability to incorporate…

Applications · Statistics 2012-10-19 Robertas Alzbutas , Tomas Iešmantas

The main purpose of this article is to alert spectroscopists, particularly those involved in surveys, to the fact that rapidly pulsating sources induce periodic structures in spectra. This would allow the detection of new classes of objects…

High Energy Astrophysical Phenomena · Physics 2010-03-18 Ermanno F. Borra