2,876 research outputs found
Photometric catalog of nearby globular clusters (I)
We present the first part of the first large and homogeneous CCD
color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular
clusters (GGC) imaged in the V and I bands using only two telescopes (one for
each hemisphere). The observed clusters represent 75% of the known Galactic
globulars with (m-M)v<=16.15 mag, cover most of the globular cluster
metallicity range (-2.2 <= [Fe/H] <= -0.4), and span Galactocentric distances
from ~1.2 to ~18.5 kpc.
In this paper, the CMDs for the 39 GGCs observed in the southern hemisphere
are presented. The remaining 13 northern hemisphere clusters of the catalog are
presented in a companion paper. For four clusters (NGC 4833, NGC 5986, NGC
6543, and NGC 6638) we present for the first time a CMD from CCD data. The
typical CMD spans from the 22nd V magnitude to the tip of the red giant branch.
Based on a large number of standard stars, the absolute photometric calibration
is reliable to the ~0.02 mag level in both filters.
This catalog, because of its homogeneity, is expected to represent a useful
data base for the measurement of the main absolute and relative parameters
characterizing the CMD of GGCs.Comment: 34 pages, 108 figures, Astronomy & Astrophysics Supplement Series, in
press. Full resolution figures can be obtained from the authors upon reques
Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia
Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are
at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the
contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of
the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives
may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze
different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and
aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features
and mathematical modelling over time was compared with the accepted model for predicting the amount of
pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2
= 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described
in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios
únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está
recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de
muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero
no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite
envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas
afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del
aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del
aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo
aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos
matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la
vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2
-ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-
Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia
Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are
at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the
contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of
the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives
may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze
different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and
aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features
and mathematical modelling over time was compared with the accepted model for predicting the amount of
pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2
= 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described
in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios
únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está
recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de
muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero
no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite
envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas
afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del
aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del
aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo
aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos
matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la
vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2
-ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-
Ronny Someck: Música d'Um Kulzum a Tel-Aviv
Rony Someck nasqué a Bagdad l'any 1951 i emigrà a Israel quan tenia a penes dos anys. Estudià literatura i filosofia hebrees a la Universitat de Tel-Aviv, ciutat on resideix i on treballa com a mestre d'Institut. El 1989, li va ser atorgat l'important premi del Primer Ministre, que és un guardó al mèrit poètic lliurat pel Primer Ministre d'Israel. Els seus poemes han estat traduïts a nombroses llengües, inclòs l'àrab, La infantesa de Ronny Someck, enmig de les tendes de campanya i de les precàries cases de ciutats de nova planta aixecades al voltant de la metròpoli de Tel-Aviv, es veu reflectida en alguns dels seus poemes. Bagdad i les palmeres a les ribes de l'Eufrat es converteixen en un paisatge perdut i enyorat. Ronny Someck poua la seva imatgeria de la cultura pop del Tel-Aviv de la seva joventut.Ronny Someck: Um Kulzum's music in Tel-Aviv
Without breaking away from the preceding generation (the one that was
born to poetic life in the first years after the establishment of the State of Israel)
as far as the tone of their speech is concerned, but showing a radical change in
their aesthetics and in their reasons for writing poetry, the present generation of
Israeli poets has given a new direction to Hebrew poetry. Pop culture, cinema,
modern art, in addition to science and philosophy, are the new elements being
used by Israeli poets in their poetic tasks.
Ronny Someck is outstanding among these writers. He was born in Baghdad
in 1951 and emigrated to Israel when he was scarcely two years old because
of the prevailing political conditions at that time. Indeed, more than
130,000 Jews left ancient Babylon between 1950 and 1953. Someck's childhood,
spent in temporary tents and precarious housing around Tel-Aviv, is reflected
in many of his poems, which also abound in social criticism and plaintive
memories of his family's uprooting. Baghdad and the palm-groves on the banks of the Euphrates stand in the rather distant background of many of his
poems.
Ronny Someck studied Hebrew literature and philosophy at Tel-Aviv University.
He lives in Tel-Aviv and teaches at a secondary school. In 1989 he was
awarded the prestigious Prime Minister's Prize for poetic excellence. Somesk's
poetic development fully justifies this award. His poems have been translated
into a number of European languages, as well as into Arabic, and they have
been included in some anthologies published in Europe and America as one of
the finest specimens of present-day Israeli poetry.
Someck's style is characterized by a concise expression and a resourceful language
that draws on the pop culture that prevailed in the Tel-Aviv of his youth.
Actors and actresses, rock singers, sportsmen, cowboys, gunmen, motorcyclists,
wild beasts recur in his poems, in which all shades of his past landscapes mix
with those of his fantasy, making a blend of vivid colours.
The article presents the Catalan translation of a selection of poems from
amongst the various books published by Ronny Someck
Centralisme monàrquic i resposta estamental: l'ambaixada valenciana del senyor de Cortes (1667-1668)
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Detection of advanced persistent threat using machine-learning correlation analysis
As one of the most serious types of cyber attack, Advanced Persistent Threats (APT) have caused major concerns on a global scale. APT refers to a persistent, multi-stage attack with the intention to compromise the system and gain information from the targeted system, which has the potential to cause significant damage and substantial financial loss. The accurate detection and prediction of APT is an ongoing challenge. This work proposes a novel machine learning-based system entitled MLAPT, which can accurately and rapidly detect and predict APT attacks in a systematic way. The MLAPT runs through three main phases: (1) Threat detection, in which eight methods have been developed to detect different techniques used during the various APT steps. The implementation and validation of these methods with real traffic is a significant contribution to the current body of research; (2) Alert correlation, in which a correlation framework is designed to link the outputs of the detection methods, aims to identify alerts that could be related and belong to a single APT scenario; and (3) Attack prediction, in which a machine learning-based prediction module is proposed based on the correlation framework output, to be used by the network security team to determine the probability of the early alerts to develop a complete APT attack. MLAPT is experimentally evaluated and the presented sy
Determinants adoption of computer assisted auditing tools (CAATs)
During the last fifteen years, several studies on technology acceptance have been pursued, and several new models have been proposed. This paper presents a theoretical background on individual acceptance of Computer-assisted Audit Tools (CAATs) in the context of statutory auditors of a European country. The adoption of technologies in auditing is considered an important factor for efficiency increasing and effectiveness of auditing work. This study identifies the adoption determinants of CAATs; and develops a CAATs, adoption model. Quantitative research was carried out and operationalized by a survey to statutory auditors. Findings indicate that the perceived usefulness of CAATs, the effort expectancy, the facilitating conditions, and the number of auditors are the main drivers of the adoption and use of CAATs. This research presents significant contributions impacting the various stakeholders: Statutory Auditors, Statutory Auditors Firms, Institutes of Statutory Auditors, and Academy.info:eu-repo/semantics/acceptedVersio
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