2,507 research outputs found
Structured computer-based training in the interpretation of neuroradiological images
Computer-based systems may be able to address a recognised need throughout the medical profession for a more structured approach to training. We describe a combined training system for neuroradiology, the MR Tutor that differs from previous approaches to computer-assisted training in radiology in that it provides case-based tuition whereby the system and user communicate in terms of a well-founded Image Description Language. The system implements a novel method of visualisation and interaction with a library of fully described cases utilising statistical models of similarity, typicality and disease categorisation of cases. We describe the rationale, knowledge representation and design of the system, and provide a formative evaluation of its usability and effectiveness
Computer discrimination between diseases of the brain based on MR image features
No description supplie
Independent Distance Learning â is it worth it?
This paper describes an approach to the management of the development of independent distance learning programmes (IDL) adopted by the University of Sunderland. The University through its Faculty of Education and Society has had significant success over many years of delivering a small number of programmes through IDL and this paper shares some of the areas that need to be addressed as more pressure is brought on programme deliverers to adopt the IDL approach. The paper goes on to explore the financial considerations, including the âat riskâ costs and the possible rewards. It is intended to act as a step-by step briefing for non-academic managers of the considerations necessary from idea to implementation, stopping short of delivery. It takes the perspective of, and its intended audience is, the managers of the process â there are many other papers and guides that deal with the distinctive pedagogy of IDL in depth and similarly many written by and for academic staff
Controlling the False Discovery Rate in Astrophysical Data Analysis
The False Discovery Rate (FDR) is a new statistical procedure to control the
number of mistakes made when performing multiple hypothesis tests, i.e. when
comparing many data against a given model hypothesis. The key advantage of FDR
is that it allows one to a priori control the average fraction of false
rejections made (when comparing to the null hypothesis) over the total number
of rejections performed. We compare FDR to the standard procedure of rejecting
all tests that do not match the null hypothesis above some arbitrarily chosen
confidence limit, e.g. 2 sigma, or at the 95% confidence level. When using FDR,
we find a similar rate of correct detections, but with significantly fewer
false detections. Moreover, the FDR procedure is quick and easy to compute and
can be trivially adapted to work with correlated data. The purpose of this
paper is to introduce the FDR procedure to the astrophysics community. We
illustrate the power of FDR through several astronomical examples, including
the detection of features against a smooth one-dimensional function, e.g.
seeing the ``baryon wiggles'' in a power spectrum of matter fluctuations, and
source pixel detection in imaging data. In this era of large datasets and high
precision measurements, FDR provides the means to adaptively control a
scientifically meaningful quantity -- the number of false discoveries made when
conducting multiple hypothesis tests.Comment: 15 pages, 9 figures. Submitted to A
Image-Processing Techniques for the Creation of Presentation-Quality Astronomical Images
The quality of modern astronomical data, the power of modern computers and
the agility of current image-processing software enable the creation of
high-quality images in a purely digital form. The combination of these
technological advancements has created a new ability to make color astronomical
images. And in many ways it has led to a new philosophy towards how to create
them. A practical guide is presented on how to generate astronomical images
from research data with powerful image-processing programs. These programs use
a layering metaphor that allows for an unlimited number of astronomical
datasets to be combined in any desired color scheme, creating an immense
parameter space to be explored using an iterative approach. Several examples of
image creation are presented.
A philosophy is also presented on how to use color and composition to create
images that simultaneously highlight scientific detail and are aesthetically
appealing. This philosophy is necessary because most datasets do not correspond
to the wavelength range of sensitivity of the human eye. The use of visual
grammar, defined as the elements which affect the interpretation of an image,
can maximize the richness and detail in an image while maintaining scientific
accuracy. By properly using visual grammar, one can imply qualities that a
two-dimensional image intrinsically cannot show, such as depth, motion and
energy. In addition, composition can be used to engage viewers and keep them
interested for a longer period of time. The use of these techniques can result
in a striking image that will effectively convey the science within the image,
to scientists and to the public.Comment: 104 pages, 38 figures, submitted to A
iCosmo: an Interactive Cosmology Package
Aims: The interactive software package iCosmo, designed to perform
cosmological calculations is described. Methods: iCosmo is a software package
to perform interactive cosmological calculations for the low redshift universe.
Computing distance measures, the matter power spectrum, and the growth factor
is supported for any values of the cosmological parameters. It also computes
derived observed quantities for several cosmological probes such as cosmic
shear, baryon acoustic oscillations and type Ia supernovae. The associated
errors for these observables can be derived for customised surveys, or for
pre-set values corresponding to current or planned instruments. The code also
allows for the calculation of cosmological forecasts with Fisher matrices which
can be manipulated to combine different surveys and cosmological probes. The
code is written in the IDL language and thus benefits from the convenient
interactive features and scientific library available in this language. iCosmo
can also be used as an engine to perform cosmological calculations in batch
mode, and forms a convenient adaptive platform for the development of further
cosmological modules. With its extensive documentation, it may also serve as a
useful resource for teaching and for newcomers in the field of cosmology.
Results: The iCosmo package is described with various examples and command
sequences. The code is freely available with documentation at
http://www.icosmo.org, along with an interactive web interface and is part of
the Initiative for Cosmology, a common archive for cosmological resources.Comment: 6 pages including 2 tables and 4 figures. Accepted and published in
Astronomy and Astrophysics. Public code and further resources available at
http://www.icosmo.or
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