898 research outputs found
From Small Talk To Academic Dialogue: An Online Professional Development Course For The English Language Proficiency Standards For Adult Education
The purpose of this capstone project was to explore the English Literacy Proficiency (ELP) Standards for Adult Education (AE) (AIR, 2016). I studied the ELP Standards for AE in order to understand how to integrate academic language learning into instruction in order to support adult English language learners in transitioning to careers and postsecondary education. This knowledge was used to design an online professional development course that supported the use and implementation of the standards. The four-week online course engaged participants in course content through integrated discussions, assignments, and materials that utilized a constructivist approach to learning
Five go to a country house: reflections on developing a residential programme for undergraduate management students.
For the academic year 2015-16, a new route was devised for undergraduate students in year three of their four-year Management degree. This route, denoted 'Connect to Business', was designed to allow students to participate in short work placements in SMEs or Third Sector organisations for two-three days per week. These placements were undertaken alongside a focused programme of personal and professional development, and taught project modules in enterprise and business consultancy. In addition, at the start of the Connect to Business year, the students were given the opportunity to take part in a three-day residential module devoted to a range of enterprise and employability topics. The design of this residential drew on lessons learned from our leadership of residential courses for students on summer placements in the Highlands and Islands of Scotland (the ScotGrad Placement Programme) and represented part of our commitment to the embedding of learning from that programme into our own curriculum. The purpose of this paper is to provide a reflective account of the Connect to Business residential programme viewed from both the student and academic perspectives. We include thoughts on programme structure and coverage, benefits realised, and challenges encountered. The points highlighted in this brief paper will be discussed more fully during the conference presentation, and the lessons learned will be discussed. The presentation will include discussion of how the changing learning and employment environment opens up opportunities to offer students new ways of learning and preparing for the world of work
Evidence for Steady Heating: Observations of an Active Region Core with Hinode and TRACE
Previous observations have not been able to exclude the possibility that high
temperature active region loops are actually composed of many small scale
threads that are in various stages of heating and cooling and only appear to be
in equilibrium. With new observations from the EUV Imaging Spectrometer (EIS)
and X-ray Telescope (XRT) on \textit{Hinode} we have the ability to investigate
the properties of high temperature coronal plasma in extraordinary detail. We
examine the emission in the core of an active region and find three independent
lines of evidence for steady heating. We find that the emission observed in XRT
is generally steady for hours, with a fluctuation level of approximately 15% in
an individual pixel. Short-lived impulsive heating events are observed, but
they appear to be unrelated to the steady emission that dominates the active
region. Furthermore, we find no evidence for warm emission that is spatially
correlated with the hot emission, as would be expected if the high temperature
loops are the result of impulsive heating. Finally, we also find that
intensities in the "moss", the footpoints of high temperature loops, are
consistent with steady heating models provided that we account for the local
expansion of the loop from the base of the transition region to the corona. In
combination, these results provide strong evidence that the heating in the core
of an active region is effectively steady, that is, the time between heating
events is short relative to the relevant radiative and conductive cooling
times.Comment: Minor changes based on the final report from the referee; Movies are
available from the first autho
Using a Differential Emission Measure and Density Measurements in an Active Region Core to Test a Steady Heating Model
The frequency of heating events in the corona is an important constraint on
the coronal heating mechanisms. Observations indicate that the intensities and
velocities measured in active region cores are effectively steady, suggesting
that heating events occur rapidly enough to keep high temperature active region
loops close to equilibrium. In this paper, we couple observations of Active
Region 10955 made with XRT and EIS on \textit{Hinode} to test a simple steady
heating model. First we calculate the differential emission measure of the apex
region of the loops in the active region core. We find the DEM to be broad and
peaked around 3\,MK. We then determine the densities in the corresponding
footpoint regions. Using potential field extrapolations to approximate the loop
lengths and the density-sensitive line ratios to infer the magnitude of the
heating, we build a steady heating model for the active region core and find
that we can match the general properties of the observed DEM for the
temperature range of 6.3 Log T 6.7. This model, for the first time,
accounts for the base pressure, loop length, and distribution of apex
temperatures of the core loops. We find that the density-sensitive spectral
line intensities and the bulk of the hot emission in the active region core are
consistent with steady heating. We also find, however, that the steady heating
model cannot address the emission observed at lower temperatures. This emission
may be due to foreground or background structures, or may indicate that the
heating in the core is more complicated. Different heating scenarios must be
tested to determine if they have the same level of agreement.Comment: 16 pages, 9 figures, accepted to Ap
2-Hydroxy-10-propargylpyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione monohydrate
The title compound, C15H14N2O3·H2O, consists of a benzodiazepinedione system fused to a pyrrole system. The seven-membered ring adopts a boat-shaped conformation (with the methine C atom as the prow); the five-membered ring adopts an enveloped-shaped conformation (with the hydroxy-bearing C atom as the flap). In the crystal, adjacent molecules are linked by O—H⋯O hydrogen bonds into sheets parallel to (102). In addition, Cacetylinic—H⋯O hydrogen bonds occur
A nanoflare model for active region radiance: application of artificial neural networks
Context. Nanoflares are small impulsive bursts of energy that blend with and
possibly make up much of the solar background emission. Determining their
frequency and energy input is central to understanding the heating of the solar
corona. One method is to extrapolate the energy frequency distribution of
larger individually observed flares to lower energies. Only if the power law
exponent is greater than 2, is it considered possible that nanoflares
contribute significantly to the energy input.
Aims. Time sequences of ultraviolet line radiances observed in the corona of
an active region are modelled with the aim of determining the power law
exponent of the nanoflare energy distribution.
Methods. A simple nanoflare model based on three key parameters (the flare
rate, the flare duration time, and the power law exponent of the flare energy
frequency distribution) is used to simulate emission line radiances from the
ions Fe XIX, Ca XIII, and Si iii, observed by SUMER in the corona of an active
region as it rotates around the east limb of the Sun. Light curve pattern
recognition by an Artificial Neural Network (ANN) scheme is used to determine
the values.
Results. The power law exponents, alpha 2.8, 2.8, and 2.6 for Fe XIX, Ca
XIII, and Si iii respectively.
Conclusions. The light curve simulations imply a power law exponent greater
than the critical value of 2 for all ion species. This implies that if the
energy of flare-like events is extrapolated to low energies, nanoflares could
provide a significant contribution to the heating of active region coronae.Comment: 4 pages, 5 figure
Flows in the solar atmosphere due to the eruptions on the 15th July, 2002
<p>Which kind of flows are present during flares? Are they compatible with the present understanding of energy release and which model best describes the observations? We analyze successive flare events in order to answer these questions. The flares were observed in the magnetically complex NOAA active region (AR) 10030 on 15 July 2002. One of them is of GOES X-class. The description of these flares and how they relate to the break-out model is presented in Gary & Moore (2004). The Coronal Diagnostic Spectrometer on board SOHO observed this active region for around 14 h. The observed emission lines provided data from the transition region to the corona with a field of view covering more than half of the active region. In this paper we analyse the spatially resolved flows seen in the atmosphere from the preflare to the flare stages. We find evidence for evaporation occurring before the impulsive phase. During the main phase, the ongoing magnetic reconnection is demonstrated by upflows located at the edges of the flare loops (while downflows are found in the flare loops themselves). We also report the impact of a filament eruption on the atmosphere, with flows up to 300 km s<sup>-1</sup> observed at transition-region temperatures in regions well away from the location of the pre-eruptive filament. Our results are consistent with the predictions of the break out model before the impulsive phase of the flare; while, as the flare progresses, the directions of the flows are consistent with flare models invoking evaporation followed by cooling and downward plasma motions in the flare loops.</p>
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Ambient solar wind's effect on ICME transit times
Most empirical and numerical models of Interplanetary Coronal Mass Ejection (ICME) propagation use the initial CME velocity as their primary, if not only, observational input. These models generally predict a wide spread of 1 AU transit times for ICMEs with the same initial velocity. We use a 3D coupled MHD model of the corona and heliosphere to determine the ambient solar wind's effect on the propagation of ICMEs from 30 solar radii to 1 AU. We quantitatively characterize this deceleration by the velocity of the upstream ambient solar wind. The effects of varying solar wind parameters on the ICME transit time are quantified and can explain the observed spread in transit times for ICMEs of the same initial velocity. We develop an adjustment formula that can be used in conjunction with other models to reduce the spread in predicted transit times of Earth-directed ICMEs
EUV spectral line formation and the temperature structure of active region fan loops: observations with Hinode/EIS and SDO/AIA
With the aim of studying AR fan loops using Hinode/EIS and SDO/AIA, we
investigate a number of inconsistencies in modeling the absolute intensities of
Fe VIII and Si VII lines, and address why their images look very similar
despite the fact that they have significantly different formation temperatures
in ionization equilibrium: log T/K = 5.6 and 5.8. These issues are important to
resolve because confidence has been undermined in their use for DEM analysis,
and Fe VIII is the main contributor to the AIA 131A channel at low
temperatures. Furthermore, they are the best EIS lines to use for velocity
studies, and for assigning the correct temperature to velocity measurements in
the fans. We find that the Fe VIII 185.213A line is particularly sensitive to
the slope of the DEM, leading to disproportionate changes in its effective
formation temperature. If the DEM has a steep gradient in the log T/K = 5.6 to
5.8 range, or is strongly peaked, Fe VIII 185.213A and Si VII 275.368A will be
formed at the same temperature. We show that this effect explains the
similarity of these images in the fans. Furthermore, we show that the most
recent ionization balance compilations resolve the discrepancies in absolute
intensities. We then combine EIS and AIA to determine the temperature structure
of a number of fan loops and find that they have peak temperatures of
0.8--1.2MK. The EIS data indicate that the temperature distribution has a
finite (but narrow) width < log sigma/K = 5.5 which, in one case, is found to
broaden substantially towards the loop base. AIA and EIS yield similar results
on the temperature, emission measure, and thermal distribution in the fans,
though sometimes the AIA data suggest a relatively larger thermal width. The
result is that both the Fe VIII 185.213A and Si VII 275.368A lines are formed
at log T/K ~ 5.9 in the fans, and the AIA 131A response also shifts to this
temperature.Comment: To be published in ApJ. Figure 6 is reduced resolution to meet size
limits. The abstract has been significantly shortened (original in PDF file
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