7,493 research outputs found
The measurement of training opportunities course outcomes: an effective policy tool?
Training Opportunities is an active labour market policy initiative, and part of a response to the entrenched problems of unemployment in Aotearoa New Zealand. The funding and implementation of Training Opportunities are determined in part by a particular system for measuring course outcomes. This paper argues that this measuring system should not be used for policy development, due to measurement errors and problems assigning causality to the intervention. Consequently, various disincentives arise that contradict the objectives of Training Opportunities. While accountability is important, the over-reliance on the narrowly defined Training Opportunities outcomes undermines the ability of providers to assist the unemployed, and thereby contribute to the policy goals of reducing unemployment and labour market disadvantage in New Zealand
Framing Social Values:\ud An Experimental Study of Culture and Cognition
How and why does a given social value come to shape the way an individual thinks, feels,and acts in a specific social situation? This study links ideas from Goffman’s frame analysis to other lines of research, proposing that dramatic narratives of variable content, vividness,and language-in-use produce variation in the accessibility of schematic, internal cultural frameworks, and, thereby, variation in the social value frames that gain situational primacy. Hypotheses derived from the argument are experimentally supported, and results encourage further research on the process of social value framing, which operates as a person crosses oundaries in the complex subcultural mosaic
Model Predictive Control Based Trajectory Generation for Autonomous Vehicles - An Architectural Approach
Research in the field of automated driving has created promising results in
the last years. Some research groups have shown perception systems which are
able to capture even complicated urban scenarios in great detail. Yet, what is
often missing are general-purpose path- or trajectory planners which are not
designed for a specific purpose. In this paper we look at path- and trajectory
planning from an architectural point of view and show how model predictive
frameworks can contribute to generalized path- and trajectory generation
approaches for generating safe trajectories even in cases of system failures.Comment: Presented at IEEE Intelligent Vehicles Symposium 2017, Los Angeles,
CA, US
Internal dynamics and membership of the NGC 3603 Young Cluster from microarcsecond astrometry
We have analyzed two epochs of HST/WFPC2 observations of the young Galactic
starburst cluster in NGC 3603 with the aim to study its internal dynamics and
stellar population. Relative proper motions measured over 10.15 yrs of more
than 800 stars enable us to distinguish cluster members from field stars. The
best-fitting isochrone yields Av=4.6-4.7 mag, a distance of 6.6-6.9 kpc, and an
age of 1 Myr for NGC 3603 Young Cluster (NYC). We identify
pre-main-sequence/main-sequence transition stars located in the short-lived
radiative-convective gap, which in the NYC occurs in the mass range 3.5-3.8
Msun. We also identify a sparse population of stars with an age of 4 Myr, which
appear to be the lower mass counterparts to previously discovered blue
supergiants located in the giant HII region NGC 3603. For the first time, we
are able to measure the internal velocity dispersion of a starburst cluster
from 234 stars with I < 18.5 mag to {\sigma}_pm1D=141+/-27 {\mu}as/yr
(4.5+/-0.8 km/s at a distance of 6.75 kpc). As stars with masses between 1.7
and 9 Msun all exhibit the same velocity dispersion, the cluster stars have not
yet reached equipartition of kinetic energy (i.e., the cluster is not in virial
equilibrium). The results highlight the power of combining high-precision
astrometry and photometry, and emphasize the role of NYC as a benchmark object
for testing stellar evolution models and dynamical models for young clusters
and as a template for extragalactic starburst clusters.Comment: 5 pages, 2 figure
Describing the soil physical characteristics of soil samples with cubical splines
The Mualem-Van Genuchten equations have become very popular in recent decades. Problems were encountered fitting the equations¿ parameters through sets of data measured in the laboratory: parameters were found which yielded results that were not monotonic increasing or decreasing. Due to the interaction between the soil moisture retention and the hydraulic conductivity relationship, some data sets yield a fit that seems not to be optimal. So the search for alternatives started. We ended with the cubical spline approximation of the soil physical characteristics. Software was developed to fit the spline-based curves to sets of measured data. Five different objective functions are tested and their results are compared for four different data sets. It is shown that the well-known least-square approximation does not always perform best. The distance between the measured points and the fitted curve, as can be evaluated numerically in a simple way, appears to yield good fits when applied as a criterion in the optimization procedure. Despite an increase in computational effort, this method is recommended over the least square method
The Discovery of a Very Massive Star in W49
Very massive stars (M>100 M) are very rare objects, but have a
strong influence on their environment. The formation of this kind of objects is
of prime importance in star formation, but observationally still poorly
constrained. We report on the identification of a very massive star in the
central cluster of the star-forming region W49. We investigate near-infrared
K-band spectroscopic observations of W49 from VLT/ISAAC together with JHK
images obtained with NTT/SOFI and LBT/LUCI. We derive a spectral type of
W49nr1, the brightest star in the dense core of the central cluster of W49. On
the basis of its K-band spectrum, W49nr1 is classified as an O2-3.5If* star
with a K-band absolute magnitude of -6.270.10 mag. The effective
temperature and bolometric correction are estimated from stars of similar
spectral type. After comparison to the Geneva evolutionary models, we find an
initial mass between 100 M and 180 M. Varying the
extinction law results in a larger initial mass range of 90 - 250 M.Comment: 5 pages, 3 figures, 1 table, accepted for publication in A&A Letter
Reconstructing the Arches I: Constraining the Initial Conditions
We have performed a series of N-body simulations to model the Arches cluster.
Our aim is to find the best fitting model for the Arches cluster by comparing
our simulations with observational data and to constrain the parameters for the
initial conditions of the cluster. By neglecting the Galactic potential and
stellar evolution, we are able to efficiently search through a large parameter
space to determine e.g. the IMF, size, and mass of the cluster. We find, that
the cluster's observed present-day mass function can be well explained with an
initial Salpeter IMF. The lower mass-limit of the IMF cannot be well
constrained from our models. In our best models, the total mass and the virial
radius of the cluster are initially (5.1 +/- 0.8) 10^4 Msun and 0.76 +/- 0.12
pc, respectively. The concentration parameter of the initial King model is w0 =
3-5.Comment: 12 pages, 14 Figures, revised and accepted for publication in MNRA
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