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Generic sequential sampling for metamodel approximations
Metamodels approximate complex multivariate data sets from simulations and experiments. These data sets often are not based on an explicitly defined function. The resulting metamodel represents a complex system's behavior for subsequent analysis or optimization. Often an exhaustive data search to obtain the data for the metalnodel is impossible, so an intelligent sampling strategy is necessary. While inultiple approaches have been advocated, the majority of these approaches were developed in support of a particular class of metamodel, known as a Kriging. A more generic, cotninonsense approach to this problem allows sequential sampling techniques to be applied to other types of metamodeis. This research compares recent search techniques for Kriging inetamodels with a generic, inulti-criteria approach combined with a new type of B-spline metamodel. This B-spline metamodel is competitive with prior results obtained with a Kriging metamodel. Furthermore, the results of this research highlight several important features necessary for these techniques to be extended to more complex domains
The well-aligned orbit of WASP-84b: evidence for disc migration
We report the sky-projected orbital obliquity (spin-orbit angle) of WASP-84b,
a 0.70- planet in a 8.52-day orbit around a G9V/K0V star, to be
. We obtain a true obliquity of from a measurement of the inclination of the stellar spin axis with
respect to the sky plane. Due to the young age and the weak tidal forcing of
the system, we suggest that the orbit of WASP-84b is unlikely to have both
realigned and circularised from the misaligned and/or eccentric orbit likely to
have arisen from high-eccentricity migration. Therefore we conclude that the
planet probably migrated via interaction with the protoplanetary disc. This
would make it the first short-orbit, giant planet to have been shown to have
migrated via this pathway. Further, we argue that the distribution of
obliquities for planets orbiting cool stars ( < 6250 K) suggests
that high-eccentricity migration is an important pathway for the formation of
short-orbit, giant planets.Comment: 6 pages, 3 figures, 1 table, submitted to ApJ
Mixed Methods Use in Project Management Research
Mixed methods research is increasingly being used in business and management disciplines, in spite of positivist traditions. The aim of the study is twofold: (1) to examine the types of mixed methods approaches being used, and (2) to determine the quality of the reporting of mixed methods studies published in the field of project management. A retrospective content analysis of articles from three ranked project management journals was undertaken for a sample period of 2004 to 2010. Our findings suggest the field of project management is in need of capacity building in relation to the good reporting of mixed methods studies
New periodic variable stars coincident with ROSAT sources discovered using SuperWASP
We present optical lightcurves of 428 periodic variable stars coincident with ROSAT X-ray sources, detected using the first run of the SuperWASP photometric survey. Only 68 of these were previously recognised as periodic variables. A further 30 of these objects are previously known pre-main sequence stars, for which we detect a modulation period for the first time. Amongst the newly identified periodic variables, many appear to be close eclipsing binaries, their X-ray emission is presumably the result of RS CVn type behaviour. Others are probably BY Dra stars, pre-main sequence stars and other rapid rotators displaying enhanced coronal activity. A number of previously catalogued pulsating variables (RR Lyr stars and Cepheids) coincident with X-ray sources are also seen, but we show hat these are likely to be misclassifications. We identify four objects which are probable low mass eclipsing binary stars, based on
their very red colour and light curve morphology
WASP-189b: an ultra-hot Jupiter transiting the bright A star HR 5599 in a polar orbit
We report the discovery of WASP-189b: an ultra-hot Jupiter in a 2.72-d
transiting orbit around the A star WASP-189 (HR 5599). We detected
periodic dimmings in the star's lightcurve, first with the WASP-South survey
facility then with the TRAPPIST-South telescope. We confirmed that a planet is
the cause of those dimmings via line-profile tomography and radial-velocity
measurements using the HARPS and CORALIE spectrographs. Those reveal WASP-189b
to be an ultra-hot Jupiter ( = 2.13 0.28 ;
= 1.374 0.082 ) in a polar orbit (; ) around a rapidly rotating
A6IV-V star ( = 8000 100 K; 100
km\, s). We calculate a predicted equilibrium temperature of = 2641 34 K, assuming zero albedo and efficient redistribution,
which is the third hottest for the known exoplanets. WASP-189 is the brightest
known host of a transiting hot Jupiter and the third-brightest known host of
any transiting exoplanet. We note that of the eight hot-Jupiter systems with
7000 K, seven have strongly misaligned orbits, and two of the
three systems with 8000 K have polar orbits (the third is
aligned).Comment: Submitted to MNRAS. 10 pages, 9 figures, 3 table
Team diversity and categorization salience : capturing diversity-blind, intergroup biased, and multicultural perceptions
It is increasingly recognized that team diversity with respect to various social categories (e.g., gender, race) does not automatically result in the cognitive activation of these categories (i.e., categorization salience), and that factors influencing this relationship are important for the effects of diversity. Thus, it is a methodological problem that no measurement technique is available to measure categorization salience in a way that efficiently applies to multiple dimensions of diversity in multiple combinations. Based on insights from artificial intelligence research, we propose a technique to capture the salience of different social categorizations in teams that does not prime the salience of these categories. We illustrate the importance of such measurement by showing how it may be used to distinguish among diversity-blind responses (low categorization salience), multicultural responses (positive responses to categorization salience), and intergroup biased responses (negative responses to categorization salience) in a study of gender and race diversity and the gender by race faultline in 38 manufacturing teams comprising 239 members
WASP-120b, WASP-122b and WASP-123b: Three newly discovered planets from the WASP-South survey
We present the discovery by the WASP-South survey of three planets transiting
moderately bright stars (V ~ 11). WASP-120b is a massive (5.0MJup) planet in a
3.6-day orbit that we find likely to be eccentric (e = 0.059+0.025-0.018)
around an F5 star. WASP-122b is a hot-Jupiter (1.37MJup, 1.79RJup) in a 1.7-day
orbit about a G4 star. Our predicted transit depth variation cause by the
atmosphere of WASP-122b suggests it is well suited to characterisation.
WASP-123b is a hot-Jupiter (0.92MJup, 1.33RJup) in a 3.0-day orbit around an
old (~ 7 Gyr) G5 star.Comment: 15 pages, 10 figures, 5 table
Standard set of health outcome measures for older persons
Background: The International Consortium for Health Outcomes Measurement (ICHOM) was founded in 2012 to propose consensus-based measurement tools and documentation for different conditions and populations.This article describes how the ICHOM Older Person Working Group followed a consensus-driven modified Delphi technique to develop multiple global outcome measures in older persons. The standard set of outcome measures developed by this group will support the ability of healthcare systems to improve their care pathways and quality of care. An additional benefit will be the opportunity to compare variations in outcomes which encourages and supports learning between different health care systems that drives quality improvement. These outcome measures were not developed for use in research. They are aimed at non researchers in healthcare provision and those who pay for these services. Methods: A modified Delphi technique utilising a value based healthcare framework was applied by an international panel to arrive at consensus decisions.To inform the panel meetings, information was sought from literature reviews, longitudinal ageing surveys and a focus group. Results: The outcome measures developed and recommended were participation in decision making, autonomy and control, mood and emotional health, loneliness and isolation, pain, activities of daily living, frailty, time spent in hospital, overall survival, carer burden, polypharmacy, falls and place of death mapped to a three tier value based healthcare framework. Conclusions: The first global health standard set of outcome measures in older persons has been developed to enable health care systems improve the quality of care provided to older persons
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