89,177 research outputs found
Remarriage After Divorce: A Longitudinal Analysis of Well Being, 1979
No full textThis study is a follow-up of Spanier (1977) "Adjustment to Separation and Divorce," also archived at the center (Log# 00738). The purpose of the follow-up was to investigate the changing patterns of remarriage and to examine the possibility that the form and functioning of first and second marriages might be different.
One hundred eighty-one of the original 205 respondents participated in the follow-up. The sample is white with a range of social classes. Sixty-two of the participants had remarried by the time of the second interview, and their spouses were interviewed as well.
Structured interviews were conducted by the Institute for Survey Research (ISR) of Temple University, covering the following topics: background information on current relationship, children living in the household, parenting and the division of responsibilities for child rearing, visitation of children not living in the household, attitudes toward stepchildren, plans for more children, relationship with former and current spouse, social network, plans for and attitudes about remarriage, physical and mental health, and economics. Many of the questions are directly comparable to those in the original data collection
Remarriage After Divorce: A Longitudinal Analysis of Well Being, 1979
No full textThis study is a follow-up of Spanier (1977) "Adjustment to Separation and Divorce," also archived at the center (Log# 00738). The purpose of the follow-up was to investigate the changing patterns of remarriage and to examine the possibility that the form and functioning of first and second marriages might be different.
One hundred eighty-one of the original 205 respondents participated in the follow-up. The sample is white with a range of social classes. Sixty-two of the participants had remarried by the time of the second interview, and their spouses were interviewed as well.
Structured interviews were conducted by the Institute for Survey Research (ISR) of Temple University, covering the following topics: background information on current relationship, children living in the household, parenting and the division of responsibilities for child rearing, visitation of children not living in the household, attitudes toward stepchildren, plans for more children, relationship with former and current spouse, social network, plans for and attitudes about remarriage, physical and mental health, and economics. Many of the questions are directly comparable to those in the original data collection
The Dubins-Spanier optimization problem in fair division theory.
No full textAbstractAn optimality criterion for fair division theory, introduced by Dubins and Spanier in 1961, is recalled with the purpose of analyzing its structure in relationship with other optimal solutions (Pareto- and equi-optimal partitions). A geometric dual approach is also defined, with the purpose of characterizing and identifying the Dubins–Spanier optimal solutions
A self-consistent and time-dependent hybrid blazar emission model
No full textAims. A time-dependent emission model for blazar jets, taking acceleration due to Fermi-I and Fermi-II processes for electrons and
protons as well as all relevant radiative processes self-consistently into account, is presented.
Methods. The presence of highly relativistic protons within the jet extends the simple synchrotron self-Compton case not only in the
very high energy radiation of blazars, but also in the X-ray regime, introducing non-linear behaviour in the emitting region of the
model by photon-meson production and emerging electron positron pair cascades.
Results. We are able to investigate the variability patterns of blazars in terms of our model in all energy bands, thus narrowing
down the parameters used. The blazar 1 ES 1011+496 serves as an example of how this model is applied to high frequency peaked
BL Lac objects in the presence of non-thermal protons within the jet. Typical multiband patterns are derived, which are experimentally
accessibl
A numerical model of parsec-scale SSC morphologies and their radio emission
No full textIn current models for jets of active galactic nuclei and their emission a shortcoming in the description and understanding of the connection between the largest and smallest scales exists. In this work we present a spatially resolved synchrotron self-Compton model extended to parsec scales, which opens the possibility of probing the connections between the radio and high-energy properties. We simulate an environment that leads to Fermi-I acceleration of leptonic particles and includes the full time dependence of this process. Omitting the restriction of a finite downstream region, we find that the spectral energy distribution produced by the accelerated particles strongly depends on their radial confinement behind the shock. The requirement, for both the restriction of high-energy emission to a small region around the shock and the production of a flat radio spectrum, is an initial linear increase of the radius immediately behind the shock, which then slows down with increasing distance from the shock. A good representation of the data for the blazar Mrk 501 is achieved by a parameterized log function. The prediction for the shape of the radio blob is given by the flux distribution with respect to shock distanc
AGN neutrino flux estimates for a realistic hybrid model
No full textRecent reports of possible correlations between high energy neutrinos observed by IceCube and Active Galactic Nuclei (AGN) activity sparked a burst of publications that attempt to predict the neutrino flux of these sources. However, often rather crude estimates are used to derive the neutrino rate from the observed photon spectra. In this work neutrino fluxes were computed in a wide parameter space. The starting point of the model was a representation of the full spectral energy density (SED) of 3C 279. The time-dependent hybrid model that was used for this study takes into account the full pγ reaction chain as well as proton synchrotron, electron-positron-pair cascades and the full SSC scheme. We compare our results to estimates frequently used in the literature. This allows to identify regions in the parameter space for which such estimates are still valid and those in which they can produce significant errors. Furthermore, if estimates for the Doppler factor, magnetic field, proton and electron densities of a source exist, the expected IceCube detection rate is readily availabl
Afterlive: A performant code for Vlasov-Hybrid simulations
No full textA parallelized implementation of the Vlasov-Hybrid method (Nunn, 1993) is presented. This method is a hybrid between a gridded Eulerian description and Lagrangian meta-particles. Unlike the Particle-in-Cell method (Dawson, 1983) which simply adds up the contribution of meta-particles, this method does a reconstruction of the distribution function f in every time step for each species. This interpolation method combines meta-particles with different weights in such a way that particles with large weight do not drown out particles that represent small contributions to the phase space density. These core properties allow the use of a much larger range of macro factors and can thus represent a much larger dynamic range in phase space density. The reconstructed phase space density f is used to calculate momenta of the distribution function such as the charge density p. The charge density p is also used as input into a spectral solver that calculates the self-consistent electrostatic field which is used to update the particles for the next time-step. Afterlive (A Fourier-based Tool in the Electrostatic limit for the Rapid Low-noise Integration of the Vlasov Equation) is fully parallelized using MPI and writes output using parallel HDF5. The input to the simulation is read from a JSON description that sets the initial particle distributions as well as domain size and discretization constraints. The implementation presented here is intentionally limited to one spatial dimension and resolves one or three dimensions in velocity space. Additional spatial dimensions can be added in a straight forward way, but make runs computationally even more costly
Entwurf und prototypische Implementierung eines Metadaten-Rahmenwerks für die Digitalisierung an der Universitätsbibliothek Regensburg
No full textAn der Universitätsbibliothek Regensburg werden in mittlerem Umfang Digitalisate erstellt. Bislang fehlte für die Digitalisate eine Erschließung mit deskriptiven, administrativen und strukturellen Metadaten, die in geeigneter Weise die Benutzbarkeit und die Langzeitarchivierung der digitalen Dokumente unterstützt hätte. Eine vergleichende Untersuchung bibliothekarischer Metadatenmodelle und -formate für die Digitalisierung ergab die besondere Eignung des Metadata Encoding and Transmission Standard (METS) als Metadatenformat für die Digitalisierung an der Universitätsbibliothek Regensburg. Der METS unterstützt ausdrücklich die Funktionalitäten des Referenzmodells eines Open Archival Information System (OAIS) und läßt sich durch standardisierte Erweiterungen an zukünftige Bedürfnisse anpassen. Die neuartige Erschließung ließ sich problemlos in den Geschäftsgang integrieren.
Ausgehend vom METS implementierte ich prototypisch ein Java-basiertes Erschließungswerkzeug, das komplett modular gestaltet ist, um größtmögliche Flexibilität für die Verarbeitung unterschiedlicher Dokumente und Dateiformate sowie für zukünftige Erweiterungen zu erreichen. Das Programm ist plattformunabhängig und als Client-Applikation konzipiert. Es soll die Erschließung der Digitalisate soweit wie möglich automatisieren.
Bei der Planung des Metadaten-Rahmenwerks erwies sich ein System zur Vergabe von Persistent Identifiern (PIDs) als notwendig. PIDs werden für CD-ROMs, METS-Dokumente und Dateien benötigt. Beim Übergang von der Speicherung der digitalen Dokumente auf CD-ROMs zu einem Online-System können die CD-ROM-PIDs entfallen. Das implementierte System zur Vergabe von PIDs kann jederzeit leicht zu einem URN-System mit Resolver weiterentwickelt werden. Neben der PID-Vergabe dient es auch der Authentizitätsprüfung für die digitalen Dokumente.
Ich demonstrierte die mögliche Erzeugung von Präsentationsformen der digitalen Dokumente, mittels XSLT aus den in METS-Dokumenten kodierten Metadaten. Dadurch ließ sich die Benutzbarkeit der Digitalisate deutlich verbessern
Aplicaciones de la cohomología de Alexander-Spanier en dinámica discreta
No full textTesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Matemáticas, leída el 23-03-2023En este trabajo, relacionamos los autovalores y autovectores de la aplicación inducida de f :X → X en homología o cohomología con propiedades dinámicas del sistema dinámico (X, f). Las teorías que mejor se adaptan a este problema son las de ˇCech ya que son las más adecuadas para describir espacios con malas propiedades locales que son situaciones comunes en dinámica, por ejemplo, los atractores extraños. Para abordar el problema anterior, utilizamos aproximaciones intrínsecas de la homología y cohomología de ˇCech (no pasamos por los complejos simpliciales para construir los complejos de cadenas o cocadenas) como las dadas en [Giraldo, Morón, Ruiz del Portal, y Sanjurjo(2001)]y [Spanier (1948)], respectivamente, que desarrollamos en el Capítulo 1. También describimos en detalle los 0 y 1-ésimos grupos de homología, y el 0-ésimo grupo de cohomología de ˇCech...In this work, we relate the eigen values and the eigen vectors of the induced map by a continuous map f : X → X on homology or cohomology to dynamic properties of the dynamical system (X, f).The theories that best fit to this problem are ˇCech's because they are the most suitable for describing spaces with bad local properties that are commun situations in dynamic, for example, strange attractors. To address the previous problem, we use intrisic approximations of ˇCech homology and cohomology (we do not go through the simplicial complex to build the chain or cochain complex) like those given in [Giraldo, Mor´on, Ruiz del Portal, y Sanjurjo(2001)] and [Spanier(1948)], respectively, that we develop in the Chapter 1. Also we describe in detail the 0th and the 1st ˇCechhomology groups, and the 0th ˇCech cohomology group...Fac. de Ciencias MatemáticasTRUEunpu
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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