408 research outputs found
PACCE: Perl Algorithm to Compute Continuum and Equivalent Widths
We present Perl Algorithm to Compute continuum and Equivalent Widths (pacce).
We describe the methods used in the computations and the requirements for its
usage. We compare the measurements made with pacce and "manual" ones made using
iraf splot task. These tests show that for SSP models the equivalent widths
strengths are very similar (differences <0.2A) for both measurements. In real
stellar spectra, the correlation between both values is still very good, but
with differences of up to 0.5A. pacce is also able to determine mean continuum
and continuum at line center values, which are helpful in stellar population
studies. In addition, it is also able to compute the uncertainties in the
equivalent widths using photon statistics. The code is made available for the
community through the web at http://www.if.ufrgs.br/~riffel/software.html.Comment: 8 pages, 5 figures, accepted by Astrophysics and Space Scienc
Blur Reduction in Ultrasonic Images Using Pseudo Three-Dimensional Wiener Filtering
The ability to quantitatively image material anomalies with ultrasonic methods is severely restricted by the axial and lateral resolution of the interrogating transducer. Axial resolution is controlled by the pulse duration of the transducer with shorter pulse durations yielding better axial resolution. Lateral resolution is controlled by the width of the interrogating beam with narrower beams providing better lateral resolutio
Information and participation in decision-making about treatments: A qualitative study of the perceptions and preferences of patients with rheumatoid arthritis
ABSTRACT Objectives: To elicit the perceptions and preferences of patients with rheumatoid arthritis regarding information and participation in treatment decision-making
Illness perceptions and quality of life in patients with non-small-cell lung cancer
__Purpose:__ Examine illness perceptions, functional health and quality of life of lung cancer patients throughout chemotherapy treatment.
__Patients and Methods:__ Longitudinal design with baseline measure 12 days after the first chemotherapy and follow-up measure 3 months later, where illness perceptions (BIPQ), functional health, and quality of life (EORTC QLQ-C-30) were measured. A total of 21 patients with non-small-cell lung cancer took part. Non-parametric testing was performed given the pilot nature of the study and the associated relatively small sample size.
__Results:__ Small to medium changes in illness perceptions and functional health between the two measurement points were detected, with both becoming more positive. More negative illness perceptions at the beginning of the treatment were associated with less functioning and lower quality of life at both beginning and end of treatment.
__Conclusion:__ Addressing illness perceptions seems a clinically relevant approach in improving functioning and quality of life of patients with non-small-cell lung cancer
Two Dimensional Pseudo-Wiener Filtering in Ultrasonic Imaging for Nondestructive Evaluation Applications
This paper deals with the use of a two dimensional pseudo-Wiener filter for ultrasonic image enhancement. Experimental results are presented to demonstrate the effectiveness of the technique for the improvement of the lateral resolution and image enhancement of ultrasonic images in materials such as graphite/epoxy composites and stainless steel. The difficulties encountered in the implementation of the filter will be delineated. Methods of overcoming some of these ‘implementational hurdles’ will be suggested
Spectroscopic variability of two Oe stars
The Oe stars HD45314 and HD60848 have recently been found to exhibit very
different X-ray properties: whilst HD60848 has an X-ray spectrum and emission
level typical of most OB stars, HD45314 features a much harder and brighter
X-ray emission, making it a so-called gamma Cas analogue. Monitoring the
optical spectra could provide hints towards the origin of these very different
behaviours. We analyse a large set of spectroscopic observations of HD45314 and
HD60848, extending over 20 years. We further attempt to fit the H-alpha line
profiles of both stars with a simple model of emission line formation in a
Keplerian disk. Strong variations in the strengths of the H-alpha, H-beta, and
He I 5876 emission lines are observed for both stars. In the case of HD60848,
we find a time lag between the variations in the equivalent widths of these
lines. The emission lines are double peaked with nearly identical strengths of
the violet and red peaks. The H-alpha profile of this star can be successfully
reproduced by our model of a disk seen under an inclination of 30 degrees. In
the case of HD45314, the emission lines are highly asymmetric and display
strong line profile variations. We find a major change in behaviour between the
2002 outburst and the one observed in 2013. This concerns both the relationship
between the equivalent widths of the various lines and their morphologies at
maximum strength (double-peaked in 2002 versus single-peaked in 2013). Our
simple disk model fails to reproduce the observed H-alpha line profiles of
HD45314. Our results further support the interpretation that Oe stars do have
decretion disks similar to those of Be stars. Whilst the emission lines of
HD60848 are explained by a disk with a Keplerian velocity field, the disk of
HD45314 seems to have a significantly more complex velocity field that could be
related to the phenomenon that produces its peculiar X-ray emission.Comment: Accepted for Publication in A&
C and N abundances of MS and SGB stars in NGC 1851
We present the first chemical analysis of stars on the double subgiant branch
(SGB) of the globular cluster NGC 1851. We obtained 48 Magellan IMACS spectra
of subgiants and fainter stars covering the spectral region between
3650-6750\AA, to derive C and N abundances from the spectral features at
4300\AA (G-band) and at ~ 3883\AA (CN). We added to our sample ~ 45 unvevolved
stars previously observed with FORS2 at the VLT. These two datasets were
homogeneously reduced and analyzed. We derived abundances of C and N for a
total of 64 stars and found considerable star-to-star variations in both [C/H]
and [N/H] at all luminosities extending to the red giant branch (RGB) base
(V~18.9). These abundances appear to be strongly anticorrelated, as would be
expected from the CN-cycle enrichment, but we did not detect any bimodality in
the C or N content. We used HST and ground-based photometry to select two
groups of faint- and bright-SGB stars from the visual and Str\"omgren
color-magnitude diagrams. Significant variations in the carbon and nitrogen
abundances are present among stars of each group, which indicates that each SGB
hosts multiple subgenerations of stars. Bright- and faint-SGB stars differ in
the total C+N content, where the fainter SGB have about 2.5 times the C+N
content of the brighter ones. Coupling our results with literature photometric
data and abundance determinations from high-resolution studies, we identify the
fainter SGB with the red-RGB population, which also should be richer on average
in Ba and other s-process elements, as well as in Na and N, when compared to
brighter SGB and the blue-RGB population.Comment: 17 pages, 3 tables, 16 figures; typos corrected, added checks on
temperature scale; A&A accepted (in press
Measuring Servitization Progress and Outcome:The Case of ‘Advanced Services’
The purpose of this paper is to establish a framework for assessing the progress and outcome of a manufacturer’s transformation towards becoming a provider of ‘advanced services’ – a complex bundling of products and services, whereby manufacturers offer capabilities and outcomes instead of products alone. ‘Advanced services’ represent the most complex offering in the current servitization trend among manufacturers. However, current performance measures lack the breadth and focus to assess progress or outcomes, and so support research and practice of organisational transformation efforts required. To address this gap the paper investigates how a manufacturer’s efforts to become an ‘advanced services’ provider can be comprehensively measured, and develops a framework for assessing the transformation journey towards becoming an ‘advanced services’ provider. The research method is based on (1) a systematic literature review process to create a comprehensive set of service-related performance measures that are available to assess a manufacturer’s servitization efforts, followed by (2) an engagement with an expert panel to synthesise the identified measures and create a set of ‘advanced services’ performance measures. The proposed framework is presented as a scorecard that can be used in practice to assess the progress and outcome of a manufacturer’s transformation towards becoming a provider of ‘advanced services’
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