573 research outputs found
Constructivist Learning Verses Explicit Teaching: A Personal Discovery of Balance
This synthesis reflects my exploration of the theories of constructivist learning, explicit teaching, and social learning in the context of my work as instructor at Children\u27s Technology Workshop- a company that runs creative technology programs for children. I provide a description of each theory with examples based on my experience at CTWorkshop and claim that while constructivist learning and explicit teaching do have some noticeable differences, they share the common element of social learning opportunities. Additionally, I argue that constructivist learning and explicit teaching are not necessarily incompatible approaches to education, but can be effectively combined to minimize the deficits and utilize the strengths of each, and such a combined approach to instruction can enhance the social learning opportunities available in the educational environment of CTWorkshop\u27s icamp program. Since this paper is reflective of my own, personal experiences working in a particular educational environment, I do not except that the specific uses of these theories described in this paper will necessarily pertain to the educational settings in which others may work; however, my intent is not to design a plan for others to use in their own instruction, but rather inspire others by my example to think more deeply about their own methods of instruction. As my reflective conclusion explains, the process of working on this project has affected me deeply, and I hope this paper may motivate others to seek their own insights
On identifying the neutron star that was born in the supernova that placed 60Fe onto the Earth
Recently, 60Fe was found in the Earth crust formed in a nearby recent
supernova (SN). If the distance to the SN and mass of the progenitor of that SN
was known, then one could constrain SN models. Knowing the positions, proper
motions, and distances of dozens of young nearby neutron stars, we can
determine their past flight paths and possible kinematic origin. Once the birth
place of a neutron star in a SN is found, we would have determined the distance
of the SN and the mass of the SN progenitor star.Comment: refereed NPA5 conference proceedings, in pres
Neutron stars from young nearby associations the origin of RXJ1605.3+3249
Many neutron stars (NSs) and runaway stars apparently come from the same
regions on the sky. This suggests that they share the same birth places, namely
associations and clusters of young massive stars. To identify NS birth places,
we attempt to and NS-runaway pairs that could be former companions that were
disrupted in a supernova (SN). The remains of recent (<few Myr) nearby (< 150
pc) SNe should still be identifiable by observing the emission of rare
radioisotopes such as 26Al and 60Fe that can also be used as additional
indicators to confirm a possible SN event. We investigated the origin of the
isolated NS RXJ1605.3+3249 and found that it was probably born ~100 pc far from
Earth 0.45 Myr ago in the extended Corona-Australis or Octans associations, or
in Sco OB4 ~1 kpc 3.5 Myr ago. A SN in Octans is supported by the
identification of one to two possible former companions the runaway stars HIP
68228 and HIP 89394, as well as the appearance of a feature in the gamma ray
emission from 26Al decay at the predicted SN place. Both, the progenitor masses
estimated by comparison with theoretical 26Al yields as well as derived from
the life time of the progenitor star, are found to be ~11MSun.Comment: accepted for publication in PASA, special volume Astronomy with
Radioactivities; 10 pages, 4 figures, 5 table
The origin of the Guitar pulsar
Among a sample of 140 OB associations and clusters, we want to identify
probable parent associations for the Guitar pulsar (PSR B2224+65) which would
then also constrain its age. For this purpose, we are using an Euler-Cauchy
technique treating the vertical component of the galactic potential to
calculate the trajectories of the pulsar and each association into the past. To
include errors we use Monte-Carlo simulations varying the initial parameters
within their error intervals. The whole range of possible pulsar radial
velocities is taken into account during the simulations. We find that the
Guitar pulsar most probably originated from the Cygnus OB3 association ~0.8 Myr
ago inferring a current radial velocity of v_r~-30 km/s, consistent with the
inclination of its bow shock.Comment: 4 pages, 1 figure, 3 table
XMM-Newton observation of PSRB2224+65 and its jet
We have investigated the pulsar PSRB2224+65 and its X-ray jet with XMM-Newton. Apart from the long X-ray jet which is almost perpendicular to the direction of proper motion, a putative extended feature at the pulsar position, which is oriented in the opposite direction to the proper motion, is also suggested by this deep X-ray imaging. Non-detection of any coherent X-ray pulsation disfavors the magnetospheric origin of the X-rays observed from the position of PSRB2224+65 and hence suggests that the interpretation of pulsar wind nebula is more viable. We have also probed the origin of PSRB2224+65 and identified a runaway star, which possibly originated from the Cygnus OB9 association, as a candidate for the former binary companion of the neutron star's progenitor. © 2012. The American Astronomical Society. All rights reserved.postprin
The 3 C’s of Consideration for COVID-19 Workplace Fever Detection Device Selection: Context, Calibration & Cost
COVID-19 screening protocols have become normal practice for employees entering workplaces around the world. However, workplace screening programs that include temperature detection via infrared thermometers or thermal detection cameras often violate many technical specifications for the correct use of these devices. Therefore, this article aims to provide practical guidance for non-thermal imaging specialists responsible for selecting thermal detection devices for workplace screening protocols. Focusing on three critical points of consideration, including the context of use, calibration of equipment, and cost of purchase and maintenance, readers are presented with a framework to guide their decision-making. This framework not only prioritizes the health and wellbeing of employees by ensuring the context of use is appropriate but balances the cost of calibration, purchasing and additional supporting supplies. Further, the presented framework extends beyond the COVID-19 pandemic and can be easily adapted to implement any new workplace technology
Transit timing variation and activity in the WASP-10 planetary system
Transit timing analysis may be an effective method of discovering additional
bodies in extrasolar systems which harbour transiting exoplanets. The
deviations from the Keplerian motion, caused by mutual gravitational
interactions between planets, are expected to generate transit timing
variations of transiting exoplanets. In 2009 we collected 9 light curves of 8
transits of the exoplanet WASP-10b. Combining these data with published ones,
we found that transit timing cannot be explained by a constant period but by a
periodic variation. Simplified three-body models which reproduce the observed
variations of timing residuals were identified by numerical simulations. We
found that the configuration with an additional planet of mass of 0.1
and orbital period of 5.23 d, located close to the outer 5:3
mean motion resonance, is the most likely scenario. If the second planet is a
transiter, the estimated flux drop will be 0.3 per cent and can be
observable with a ground-based telescope. Moreover, we present evidence that
the spots on the stellar surface and rotation of the star affect the radial
velocity curve giving rise to spurious eccentricity of the orbit of the first
planet. We argue that the orbit of WASP-10b is essentially circular. Using the
gyrochronology method, the host star was found to be Myr old. This
young age can explain the large radius reported for WASP-10b.Comment: MNRAS accepte
Towards the Rosetta Stone of planet formation
Transiting exoplanets (TEPs) observed just about 10 Myrs after formation of
their host systems may serve as the Rosetta Stone for planet formation
theories. They would give strong constraints on several aspects of planet
formation, e.g. time-scales (planet formation would then be possible within 10
Myrs), the radius of the planet could indicate whether planets form by
gravitational collapse (being larger when young) or accretion growth (being
smaller when young). We present a survey, the main goal of which is to find and
then characterise TEPs in very young open clusters.Comment: Poster contribution to Detection and Dynamics of Transiting
Exoplanets (Haute Provence Observatory Colloquium, 23-27 August 2010
- …