779 research outputs found
EXIST's Gamma-Ray Burst Sensitivity
We use semi-analytic techniques to evaluate the burst sensitivity of designs
for the EXIST hard X-ray survey mission. Applying these techniques to the
mission design proposed for the Beyond Einstein program, we find that with its
very large field-of-view and faint gamma-ray burst detection threshold, EXIST
will detect and localize approximately two bursts per day, a large fraction of
which may be at high redshift. We estimate that EXIST's maximum sensitivity
will be ~4 times greater than that of Swift's Burst Alert Telescope. Bursts
will be localized to better than 40 arcsec at threshold, with a burst position
as good as a few arcsec for strong bursts. EXIST's combination of three
different detector systems will provide spectra from 3 keV to more than 10 MeV.
Thus, EXIST will enable a major leap in the understanding of bursts, their
evolution, environment, and utility as cosmological probes.Comment: 25 pages, 10 figures, accepted by Ap
Neural Network-Based Equations for Predicting PGA and PGV in Texas, Oklahoma, and Kansas
Parts of Texas, Oklahoma, and Kansas have experienced increased rates of
seismicity in recent years, providing new datasets of earthquake recordings to
develop ground motion prediction models for this particular region of the
Central and Eastern North America (CENA). This paper outlines a framework for
using Artificial Neural Networks (ANNs) to develop attenuation models from the
ground motion recordings in this region. While attenuation models exist for the
CENA, concerns over the increased rate of seismicity in this region necessitate
investigation of ground motions prediction models particular to these states.
To do so, an ANN-based framework is proposed to predict peak ground
acceleration (PGA) and peak ground velocity (PGV) given magnitude, earthquake
source-to-site distance, and shear wave velocity. In this framework,
approximately 4,500 ground motions with magnitude greater than 3.0 recorded in
these three states (Texas, Oklahoma, and Kansas) since 2005 are considered.
Results from this study suggest that existing ground motion prediction models
developed for CENA do not accurately predict the ground motion intensity
measures for earthquakes in this region, especially for those with low
source-to-site distances or on very soft soil conditions. The proposed ANN
models provide much more accurate prediction of the ground motion intensity
measures at all distances and magnitudes. The proposed ANN models are also
converted to relatively simple mathematical equations so that engineers can
easily use them to predict the ground motion intensity measures for future
events. Finally, through a sensitivity analysis, the contributions of the
predictive parameters to the prediction of the considered intensity measures
are investigated.Comment: 5th Geotechnical Earthquake Engineering and Soil Dynamics Conference,
Austin, TX, USA, June 10-13. (2018
ProtoEXIST: Advanced Prototype CZT Coded Aperture Telescopes for EXIST
{\it ProtoEXIST1} is a pathfinder for the {\it EXIST-HET}, a coded aperture
hard X-ray telescope with a 4.5 m CZT detector plane a 9070 degree
field of view to be flown as the primary instrument on the {\it EXIST} mission
and is intended to monitor the full sky every 3 h in an effort to locate GRBs
and other high energy transients. {\it ProtoEXIST1} consists of a 256 cm
tiled CZT detector plane containing 4096 pixels composed of an 88 array
of individual 1.95 cm 1.95 cm 0.5 cm CZT detector modules
each with a 8 8 pixilated anode configured as a coded aperture
telescope with a fully coded field of view employing
passive side shielding and an active CsI anti-coincidence rear shield, recently
completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009.
During the duration of its 6 hour flight on-board calibration of the detector
plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along
with the simultaneous measurement of the background spectrum and an observation
of Cygnus X-1. Here we recount the events of the flight and report on the
detector performance in a near space environment. We also briefly discuss {\it
ProtoEXIST2}: the next stage of detector development which employs the {\it
NuSTAR} ASIC enabling finer (3232) anode pixilation. When completed
{\it ProtoEXIST2} will consist of a 256 cm tiled array and be flown
simultaneously with the ProtoEXIST1 telescope
Efficacy of Online Training for Improving Camp Staff Competency
Preparing competent staff is a critical issue within the camp community. This quasi-experimental study examined the effectiveness of an online course for improving staff competency in camp healthcare practices among college-aged camp staff and a comparison group (N = 55). We hypothesized that working in camp would increase competency test scores due to opportunities for staff to experientially apply knowledge learned online. Hierarchical linear modeling was used to analyse the cross-level effects of a between-individuals factor (assignment to experimental or comparison group) and within-individual effects of time (pre-test, post-test #1, and post-test #2) on online course test scores. At post-test #2, the difference in average test scores between groups was ~30 points, with the treatment group scoring lower on average than the comparison group. Factors that may have influenced these findings are explored, including fatigue and the limited durability of online learning. Recommendations for research and practice are discussed
EXIST\u27S Gamma-Ray Burst Sensitivity
We use semianalytic techniques to evaluate the burst sensitivity of designs for the EXIST hard X-ray survey mis-sion. Applying these techniques to the mission design proposed for the Beyond Einstein program,we find that with its very large field of view and faint gamma-ray burst detection threshold, EXIST will detect and localize approximately two bursts per day, a large fraction of which may be at high redshift. We estimate that EXIST’s maximum sensitivity will be ~4 times greater than that of Swift’s Burst Alert Telescope. Bursts will be localized to better than 40 at thresh-old, with a burst position as good asa few arcsecondsfor strong bursts. EXIST’s combination of three different detector systems will provide spectra from 3 keV to more than 10 MeV. Thus, EXIST will enable a major leap in the understand-ing of bursts, their evolution, environment, and utility as cosmological probes
Integrating quality into the cycle of therapeutic development
The quality of healthcare, particularly as reflected in current practice versus the available evidence, has become a major focus of national health policy discussions. Key components needed to provide quality care include: 1) development of quality indicators and performance measures from specific practice guidelines, 2) better ways to disseminate such guidelines and measures, and 3) development of support tools to promote standardized practice. Although rational decision-making and development of practice guidelines have relied upon results of randomized trials and outcomes studies, not all questions can be answered by randomized trials, and many treatment decisions necessarily reflect physiology, intuition, and experience when treating individuals. Debate about the role of "evidence-based medicine" also has raised questions about the value of applying trial results in practice, and some skepticism has arisen about whether advocated measures of clinical effectiveness, the basic definition of quality, truly reflect a worthwhile approach to improving medical practice. We provide a perspective on this issue by describing a model that integrates quantitative measurements of quality and performance into the development cycle of existing and future therapeutics. Such a model would serve as a basic approach to cardiovascular medicine that is necessary, but not sufficient, to those wishing to provide the best care for their patients
Preparing to work: dramaturgy, cynicism and normative ‘remote’ control in the socialization of graduate recruits in management consulting
online) This paper examines the socialization of graduate recruits into a knowledge intensive labour
process and organizational culture. Theoretically the paper draws upon the idea of ‘preparing
for work’ to position this early socialization as a crucial moment in the production of
subjectivities suited (and booted) for the labour process of management consulting. Empirically
the paper reports on a two-day induction session for new graduate recruits joining a global
management consultancy and their responses to this training. Particular attention is given to
the use of role-play and a dramaturgical workshop used in part of the training process. The paper
argues that the utilization of dramaturgy in training is consistent with the overall approach to
control developed in the firm in response to the fact that the labour process of consulting is
often conducted on client sites, away from any direct supervisory gaze. As such, the consultants
were subjected to a form of cultural control that was designed to function independently of
direct supervision. This control did not operate directly upon the new employees professed
values, however, but at one step removed so that a ‘cynical distance’ from the content of the
organization’s culture was accepted so long as a professional ‘ethic of behaviour’ was
established. By focusing on an ‘ethic of behaviour’ these young professionals were encouraged
to internalize a self-control akin to that of an actor, rather than internalizing the corporate values
entirely
Exploring older women's confidence during route planning
In-car route guidance is automatic, requiring a minimum of time and thinking. This paper explores the use of personalised information when providing instructions for navigating a journey. We focus on older women with a lifetime of experience. Ten female participants were interviewed to elicit their comfort zone with respect to navigating in a car from their own home. Two routes were then devised for each participant, which extended beyond this comfort zone, and presented to them in two different formats. Participants then navigated the route of their least preferred format. Questionnaires and interviews were used to explore the effects of the formats on their confidence, cognitive effort and use of cognitive mapping facilities. The questionnaire data showed that the more detailed instructions supported cognitive mapping processes and the interviews suggested that this support was valued prio
Tensor Ayy and vector Ay analyzing powers in the H(d,d')X and ^{12}C(d,d')X reactons at initial deuteron momenta of 9 GeV/c in the region of baryonic resonances excitation
The angular dependence of the tensor Ayy and vector Ay analyzing powers in
the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen
and carbon have been measured. The range of measurements corresponds to the
baryonic resonance excitation with masses 2.2--2.6 GeV/c^2. The Ayy data being
in good agreement with the previous results demonstrate an approximate
scaling up to -1.5 (GeV/c)^2. The large values of A_y show a significant role
of the spin-dependent part of the elementary amplitude of the NN->NN* reaction.
The results of the experiment are compared with model predictions of the
plane-wave impulse approximation.Comment: 7 pages, 7 figures. submitted to Yad.Fi
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