Burnout and Its Antecedents:Considering Both Work and Household Time Claims, and Flexibility in Relation to Burnout

This study contributes to the previous literature by examining how flexible work arrangements interact with work and family time claims to affect burnout. It does so by providing a theoretical framework and empirical test of the interaction of flexibility with the effect of work and family time claims on burnout. Hypotheses and predictions based on previous literature are tested by Ordinary Least Squared regression models using data from the Time Competition Survey, constituting a sample of 1,058 employees of 89 function groups within 30 organizations. We found no main effects of work and family time claims or flexible work arrangements on burnout. However, the results do show an interaction of flexible working hours with the effect of work and family time claims on burnout. Specifically, the higher an individual's work and family time claims, the more this person benefits from having flexible working hours. In general, the results support the proposition that the relationship between work and family time claims and burnout differs for individuals with different levels of flexible work arrangements.</p

Tur\'an Graphs, Stability Number, and Fibonacci Index

The Fibonacci index of a graph is the number of its stable sets. This parameter is widely studied and has applications in chemical graph theory. In this paper, we establish tight upper bounds for the Fibonacci index in terms of the stability number and the order of general graphs and connected graphs. Tur\'an graphs frequently appear in extremal graph theory. We show that Tur\'an graphs and a connected variant of them are also extremal for these particular problems.Comment: 11 pages, 3 figure

Exploiting lattice structures in shape grammar implementations

The ability to work with ambiguity and compute new designs based on both defined and emergent shapes are unique advantages of shape grammars. Realizing these benefits in design practice requires the implementation of general purpose shape grammar interpreters that support: (a) the detection of arbitrary subshapes in arbitrary shapes and (b) the application of shape rules that use these subshapes to create new shapes. The complexity of currently available interpreters results from their combination of shape computation (for subshape detection and the application of rules) with computational geometry (for the geometric operations need to generate new shapes). This paper proposes a shape grammar implementation method for three-dimensional circular arcs represented as rational quadratic Bézier curves based on lattice theory that reduces this complexity by separating steps in a shape computation process from the geometrical operations associated with specific grammars and shapes. The method is demonstrated through application to two well-known shape grammars: Stiny's triangles grammar and Jowers and Earl's trefoil grammar. A prototype computer implementation of an interpreter kernel has been built and its application to both grammars is presented. The use of Bézier curves in three dimensions opens the possibility to extend shape grammar implementations to cover the wider range of applications that are needed before practical implementations for use in real life product design and development processes become feasible

A search for VHE counterparts of Galactic Fermi bright sources and MeV to TeV spectral characterization

Very high-energy (VHE; E>100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as pulsar wind nebulae (PWNe), supernova remnants (SNRs), giant molecular clouds, gamma-ray binaries, the Galactic Center, active galactic nuclei (AGN), radio galaxies, starburst galaxies, and possibly star-forming regions as well. At lower energies, observations using the Large Area Telescope (LAT) onboard Fermi provide a rich set of data which can be used to study the behavior of cosmic accelerators in the MeV to TeV energy bands. In particular, the improved angular resolution of current telescopes in both bands compared to previous instruments significantly reduces source confusion and facilitates the identification of associated counterparts at lower energies. In this paper, a comprehensive search for VHE gamma-ray sources which are spatially coincident with Galactic Fermi/LAT bright sources is performed, and the available MeV to TeV spectra of coincident sources are compared. It is found that bright LAT GeV sources are correlated with TeV sources, in contrast to previous studies using EGRET data. Moreover, a single spectral component seems unable to describe the MeV to TeV spectra of many coincident GeV/TeV sources. It has been suggested that gamma-ray pulsars may be accompanied by VHE gamma-ray emitting nebulae, a hypothesis that can be tested with VHE observations of these pulsars.Comment: Astronomy and Astrophysics, in press, 17 pages, 12 figures, 5 table

A generalized likelihood ratio test statistic for Cherenkov telescope data

Astrophysical sources of TeV gamma rays are usually established by Cherenkov telescope observations. These counting type instruments have a field of view of few degrees in diameter and record large numbers of particle air showers via their Cherenkov radiation in the atmosphere. The showers are either induced by gamma rays or diffuse cosmic ray background. The commonly used test statistic to evaluate a possible gamma-ray excess is Li and Ma (1983), Eq. 17, which can be applied to independent on- and off-source observations, or scenarios that can be approximated as such. This formula however is unsuitable if the data are taken in so-called "wobble" mode (pointing to several offset positions around the source), if at the same time the acceptance shape is irregular or even depends on operating parameters such as the pointing direction or telescope multiplicity. To provide a robust test statistic in such cases, this paper explores a possible generalization of the likelihood ratio concept on which the formula of Li and Ma is based. In doing so, the multi-pointing nature of the data and the typically known instrument point spread function are fully exploited to derive a new, semi-numerical test statistic. Due to its flexibility and robustness against systematic uncertainties, it is not only useful for detection purposes, but also for skymapping and source shape fitting. Simplified Monte Carlo simulations are presented to verify the results, and several applications and further generalizations of the concept are discussed.Comment: 27 pages, 8 figure

Testing CP Violation in ZZH Interactions at the LHC

We study genuine CP-odd observables at the LHC to test the CP property of the ZZH interaction for a Higgs boson with mass below the threshold to a pair of gauge bosons via the process p,p -> Z,H -> l+,l-,b,bbar. We illustrate the analysis by including a CP-odd ZZH coupling, and show how to extract the CP asymmetries in the signal events. After selective kinematical cuts to suppress the SM backgrounds plus an optimal Log-likelihood analysis, we find that, with a CP violating coupling btilde = 0.25, a CP asymmetry may be established at a 3 sigma (5 sigma) level with an integrated luminosity of about 30 (50) fb^-1 at the LHC.Comment: 14 pages, 13 figures, revtex

Hydrothermal Carbonization: Modeling, Final Properties Design and Applications: A Review

Active research on biomass hydrothermal carbonization (HTC) continues to demonstrate its advantages over other thermochemical processes, in particular the interesting benefits that are associated with carbonaceous solid products, called hydrochar (HC). The areas of applications of HC range from biofuel to doped porous material for adsorption, energy storage, and catalysis. At the same time, intensive research has been aimed at better elucidating the process mechanisms and kinetics, and how the experimental variables (temperature, time, biomass load, feedstock composition, as well as their interactions) affect the distribution between phases and their composition. This review provides an analysis of the state of the art on HTC, mainly with regard to the effect of variables on the process, the associated kinetics, and the characteristics of the solid phase (HC), as well as some of the more studied applications so far. The focus is on research made over the last five years on these topics. © 2018 by the authors. Licensee MDPI, Basel, Switzerland

K^+ momentum spectrum from (K^-,K^+) reactions in intranuclear cascade model

In a framework of intranuclear cascade (INC) type calculation, we study a momentum spectrum in reactions \KK at a beam momentum of 1.65 GeV/c. INC model calculations are compared with the relativistic impulse approximation (RIA) calculations to perform the detailed study of the reaction mechanism. We find that the INC model can reproduce the experimental data on various targets. Especially, in the low-momentum region, the forward-angle cross sections of the $(K^-,K^+)$ reaction on from light to heavy targets are consistently explained with the two-step strangeness exchange and production processes with various intermediate mesons, and $\phi$, $a_0$ and $f_0$ productions and their decay into $K^+K^-$. In the two-step processes, inclusion of meson and hyperon resonances is found to be essential.Comment: LaTeX file and 12ps figure

Hydrothermal carbonization: modeling, final properties design and applications: a review

La investigación activa sobre la carbonización hidrotermal de la biomasa (HTC) sigue demostrando sus ventajas sobre otros procesos termoquímicos, en particular los interesantes beneficios que se asocian a los productos sólidos carbonosos, llamados hidrocarburos (HC). Las esferas de aplicación del HC van desde el biocombustible hasta el material poroso dopado para la adsorción, el almacenamiento de energía y la catálisis. Al mismo tiempo, se han realizado intensas investigaciones para dilucidar mejor los mecanismos y la cinética del proceso, y la forma en que las variables experimentales (temperatura, tiempo, carga de biomasa, composición de la materia prima, así como sus interacciones) afectan a la distribución entre las fases y a su composición. En este examen se analiza el estado de la técnica en materia de HTC, principalmente en lo que respecta al efecto de las variables en el proceso, la cinética asociada y las características de la fase sólida (HC), así como algunas de las aplicaciones más estudiadas hasta ahora. El foco de atención se centra en las investigaciones realizadas en los últimos cinco años sobre estos temas.Active research on biomass hydrothermal carbonization (HTC) continues to demonstrate its advantages over other thermochemical processes, in particular the interesting benefits that are associated with carbonaceous solid products, called hydrochar (HC). The areas of applications of HC range from biofuel to doped porous material for adsorption, energy storage, and catalysis. At the same time, intensive research has been aimed at better elucidating the process mechanisms and kinetics, and how the experimental variables (temperature, time, biomass load, feedstock composition, as well as their interactions) affect the distribution between phases and their composition. This review provides an analysis of the state of the art on HTC, mainly with regard to the effect of variables on the process, the associated kinetics, and the characteristics of the solid phase (HC), as well as some of the more studied applications so far. The focus is on research made over the last five years on these topics.• Junta de Extremadura. Proyecto GR15034 • Ministerio de Economía y Competitividad. Proyectos CTM2014-55998-R (I+D+i), CTM2016-75937-R • USDA-Agricultural Research Service National Program 212peerReviewe