10,391 research outputs found
Recommended from our members
Experimental Methods in IIR: The Tension between Rigour and Ethics in Studies Involving Users with Dyslexia
Designing user studies in the interactive information retrieval (IIR) paradigm on people with impairments may sometimes require different methodological considerations than for other users. Consequently, there may be a tension between what the community regards as being a rigorous methodology against what researchers can do ethically with their users. This paper discusses issues to consider when designing IIR studies involving people with dyslexia, such as sampling, informed consent and data collection. The conclusion is that conducting user studies on participants with dyslexia requires special considerations at all stages of the experimental design. The purpose of this paper is to raise awareness and understanding in the research community about experimental methods involving users with dyslexia, and addresses researchers, as well as editors and reviewers. Several of the issues raised do not only apply to people with dyslexia, but have implications when researching other groups, for instance elderly people and users with learning, cognitive, sensory or motor impairments
Lie algebra and invariant tensor technology for g2
Proceeding in analogy with su(n) work on lambda matrices and f- and
d-tensors, this paper develops the technology of the Lie algebra g2, its seven
dimensional defining representation gamma and the full set of invariant tensors
that arise in relation thereto. A comprehensive listing of identities involving
these tensors is given. This includes identities that depend on use of
characteristic equations, especially for gamma, and a good body of results
involving the quadratic, sextic and (the non-primitivity of) other Casimir
operators of g2.Comment: 29 pages, LaTe
Results of post-test psychological examinations of the crewmen from the 90-day manned test of an advanced regenerative life support system
The following material presents the results of two temporally remote administrations of an identical projective personality assessment device (Rorschach Inkblot) using crew members aboard the 90-day test. The first administration took place during preselection crew psychodiagnostic testing in the period extending from mid-December 1969 through mid-January 1970. Second administration took place in late May and early June, 1971, approximately one year after termination of the test. During the 90-day program duration, the subjects participated in the crew training program, were selected and served as onboard crew during the 90-day test. The testing was undertaken in order to determine the character and extent of change (if any) in basic personality dynamics accompanying or caused by participation in the 90-day test program. Results indicate that significant personality changes occurred in three of the four onboard crew members. A detailed discussion of the results is provided. Objective scores which served as the basis for the discussion are presented in the Appendix
On characteristic equations, trace identities and Casimir operators of simple Lie algebras
Two approaches are developed to exploit, for simple complex or compact real
Lie algebras g, the information that stems from the characteristic equations of
representation matrices and Casimir operators. These approaches are selected so
as to be viable not only for `small' Lie algebras and suitable for treatment by
computer algebra. A very large body of new results emerges in the forms, a) of
identities of a tensorial nature, involving structure constants etc. of g, b)
of trace identities for powers of matrices of the adjoint and defining
representations of g, c) of expressions of non-primitive Casimir operators of g
in terms of primitive ones. The methods are sufficiently tractable to allow not
only explicit proof by hand of the non-primitive nature of the quartic Casimir
of g2, f4, e6, but also e.g. of that of the tenth order Casimir of f4.Comment: 39 pages, 8 tables, late
Recommended from our members
Why Local Authorities should prepare Food Brexit Plans
The UK’s food supply will be affected by Brexit whatever the outcome of the Parliamentary vote on the Draft Withdrawal Agreement. As the 29 March 2019 date for leaving the EU approaches, preparations to ensure we maintain a safe, adequate and sustainable food supply need to start urgently. Local Authorities (LAs) have a vital part to play in these preparations. More guidance, paying attention to the food specifics, is felt to be needed.
LAs have a key role in the UK’s food system, with responsibilities including the enforcement of food safety and standards regulation, the control of imported food at ports and airports and the certification of foods for export. They also have unique knowledge of relevant local professionals, institutions, businesses and networks.
This briefing aims to help Local Authorities prepare for Food Brexit. It shows why LAs should prepare Food Brexit Plans, and outlines five courses of action they could consider.
The briefing recommends that Local Authorities:
• Create Food Resilience Teams
• Anticipate and reduce the impact of Food Brexit, particularly on SMEs
• Narrow the information gap and treat the public openly and fairly
• Prepare for public engagement
• Be a local food voice so that central government knows the local realities
7-Li(p,n) Nuclear Data Library for Incident Proton Energies to 150 MeV
We describe evaluation methods that make use of experimental data, and
nuclear model calculations, to develop an ENDF-formatted data library for the
reaction p + Li7 for incident protons with energies up to 150 MeV. The
important 7-Li(p,n_0) and 7-Li(p,n_1) reactions are evaluated from the
experimental data, with their angular distributions represented using Lengendre
polynomial expansions. The decay of the remaining reaction flux is estimated
from GNASH nuclear model calculations. The evaluated ENDF-data are described in
detail, and illustrated in numerous figures. We also illustrate the use of
these data in a representative application by a radiation transport simulation
with the code MCNPX.Comment: 11 pages, 8 figures, LaTeX, submitted to Proc. 2000 ANS/ENS
International Meeting, Nuclear Applications of Accelerator Technology
(AccApp00), November 12-16, Washington, DC, US
Bulk spectral function sum rule in QCD-like theories with a holographic dual
We derive the sum rule for the spectral function of the stress-energy tensor
in the bulk (uniform dilatation) channel in a general class of strongly coupled
field theories. This class includes theories holographically dual to a theory
of gravity coupled to a single scalar field, representing the operator of the
scale anomaly. In the limit when the operator becomes marginal, the sum rule
coincides with that in QCD. Using the holographic model, we verify explicitly
the cancellation between large and small frequency contributions to the
spectral integral required to satisfy the sum rule in such QCD-like theories.Comment: 16 pages, 2 figure
Recommended from our members
Analysing Creative Image Search Information Needs
Creative professionals in advertising, marketing, design and journalism search for images to visually represent a concept for their project. The main purpose of this paper is to present search facets derived from an analysis of documents known as briefs, which are widely used in creative industries as requirement documents describing information needs. The briefs specify the type of image required, such as the content and context of use for the image and represent the topic from which the searcher builds an image query. We take three main sources—user image search behaviour, briefs, and image search engine search facets to examine the search facets for image searching in order to examine the following research question—are search facet schemes for image search engines sufficient for user needs, or is revision needed? We found that there are three main classes of user search facet, which include business, contextual and image related information. The key argument in the paper is that the facet “keyword/tag” is ambiguous and does not support user needs for more generic descriptions to broaden search or specific descriptions to narrow their search — we suggest that a more detailed search facet scheme would be appropriate
Modeling solutions to Tanzania's physician workforce challenge.
BACKGROUND:There is a great need for physicians in Tanzania. In 2012, there were approximately 0.31 physicians per 10,000 individuals nationwide, with a lower ratio in the rural areas, where the majority of the population resides. In response, universities across Tanzania have greatly increased the enrollment of medical students. Yet evidence suggests high attrition of medical graduates to other professions and emigration from rural areas where they are most needed. OBJECTIVE:To estimate the future number of physicians practicing in Tanzania and the potential impact of interventions to improve retention, we built a model that tracks medical students from enrollment through clinical practice, from 1990 to 2025. DESIGN:We designed a Markov process with 92 potential states capturing the movement of 25,000 medical students and physicians from medical training through employment. Work possibilities included clinical practice (divided into rural or urban, public or private), non-clinical work, and emigration. We populated and calibrated the model using a national 2005/2006 physician mapping survey, as well as graduation records, graduate tracking surveys, and other available data. RESULTS:The model projects massive losses to clinical practice between 2016 and 2025, especially in rural areas. Approximately 56% of all medical school students enrolled between 2011 and 2020 will not be practicing medicine in Tanzania in 2025. Even with these losses, the model forecasts an increase in the physician-to-population ratio to 1.4 per 10,000 by 2025. Increasing the absorption of recent graduates into the public sector and/or developing a rural training track would ameliorate physician attrition in the most underserved areas. CONCLUSIONS:Tanzania is making significant investments in the training of physicians. Without linking these doctors to employment and ensuring their retention, the majority of this investment in medical education will be jeopardized
- …
