20,384 research outputs found
Application of ride quality technology to predict ride satisfaction for commuter-type aircraft
A method was developed to predict passenger satisfaction with the ride environment of a transportation vehicle. This method, a general approach, was applied to a commuter-type aircraft for illustrative purposes. The effect of terrain, altitude and seat location were examined. The method predicts the variation in passengers satisfied for any set of flight conditions. In addition several noncommuter aircraft were analyzed for comparison and other uses of the model described. The method has advantages for design, evaluation, and operating decisions
ALMA data suggest the presence of a spiral structure in the inner wind of CW Leo
(abbreviated) We aim to study the inner wind of the well-known AGB star CW
Leo. Different diagnostics probing different geometrical scales have pointed
toward a non-homogeneous mass-loss process: dust clumps are observed at
milli-arcsec scale, a bipolar structure is seen at arcsecond-scale and
multi-concentric shells are detected beyond 1". We present the first ALMA Cycle
0 band 9 data around 650 GHz. The full-resolution data have a spatial
resolution of 0".42x0".24, allowing us to study the morpho-kinematical
structure within ~6". Results: We have detected 25 molecular lines. The
emission of all but one line is spatially resolved. The dust and molecular
lines are centered around the continuum peak position. The dust emission has an
asymmetric distribution with a central peak flux density of ~2 Jy. The
molecular emission lines trace different regions in the wind acceleration
region and suggest that the wind velocity increases rapidly from about 5 R*
almost reaching the terminal velocity at ~11 R*. The channel maps for the
brighter lines show a complex structure; specifically for the 13CO J=6-5 line
different arcs are detected within the first few arcseconds. The curved
structure present in the PV map of the 13CO J=6-5 line can be explained by a
spiral structure in the inner wind, probably induced by a binary companion.
From modeling the ALMA data, we deduce that the potential orbital axis for the
binary system lies at a position angle of ~10-20 deg to the North-East and that
the spiral structure is seen almost edge-on. We infer an orbital period of 55
yr and a binary separation of 25 au (or ~8.2 R*). We tentatively estimate that
the companion is an unevolved low-mass main-sequence star. The ALMA data hence
provide us for the first time with the crucial kinematical link between the
dust clumps seen at milli-arcsecond scale and the almost concentric arcs seen
at arcsecond scale.Comment: 22 pages, 18 Figures, Astronomy & Astrophysic
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A content, pedagogy and technology [CPT] approach to TPACK
TPACK is a framework for the learning process in which educators combine Technological, Pedagogical and Content Knowledge to deliver the learning experience. Therefore, TPACK can be defined as a complex interaction between the
technology, pedagogy and content. TPACK expresses the overlap between these factors in a two-dimensional space, placing TPACK at the centre. Educators can place their teaching episode within this space and ask, if I place my delivery at this point is it the best point in the TPACK space? Secondly educators may ask how can the best point within the space be determined? The CPT model proposes an attempt to address these questions by recasting TPACK as a three-dimensional pseudo-vector space allowing expected
outcomes and observed outcomes to be analysed. For the study presented here our null hypothesis is: H0 = there is no significant difference between the observed and expected outcomes
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Developing a predictive model for the enhanced learning outcomes by the use of technology
This paper reports on the initial outcomes of a study to develop a model to identify the relationship between technological facilities such as iPad, MacBook, Apps and software etc., pedagogy (that can be defined as any conscious activity by one person designed to enhance learning in another (Watkins and Mortimore, 1999 [1])), curriculum and learning. The new model can be called CPT Model. This is a new area of study. The model will test the difference between the observed learning outcomes and the learning outcomes predicted. This model can predict the outcomes for assessing the students’ progress. Using a three-dimensional vector space in the form of 3D equations, after the integration between the ICT and the education, students’ observed and predicted progress (that was calculated using the CPT model) were compared. These rates were very close to each other. Therefore the null hypothesis, "there is not a significant difference between the observed (actual) and expected outcomes"
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