932 resultados para Field of Library Science
Resumo:
Wavefront coding is a powerful technique that can be used to extend the depth of field of an incoherent imaging system. By adding a suitable phase mask to the aperture plane, the optical transfer function of a conventional imaging system can be made defocus invariant. Since 1995, when a cubic phase mask was first suggested, many kinds of phase masks have been proposed to achieve the goal of depth extension. In this Letter, a phase mask based on sinusoidal function is designed to enrich the family of phase masks. Numerical evaluation demonstrates that the proposed mask is not only less sensitive to focus errors than cubic, exponential, and modified logarithmic masks are, but it also has a smaller point-spread-function shifting effect. (C) 2010 Optical Society of America
Resumo:
Wave-front coding is a well known technique used to extend the depth of field of incoherent imaging system. The core of this technique lies in the design of suitable phase masks, among which the most important one is the cubic phase mask suggested by Dowski and Cathey (1995) [1]. In this paper, we propose a new type called cubic sinusoidal phase mask which is generated by combing the cubic one and another component having the sinusoidal form. Numerical evaluations and real experimental results demonstrate that the composite phase mask is superior to the original cubic phase mask with parameters optimized and provides another choice to achieve the goal of depth extension. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
Urquhart, C., Spink, S. & Thomas, R., Assessing training and professional development needs of library staff. Report for National Library of Health. (2005). Aberystwyth: Department of Information Studies, University of Wales Aberystwyth Sponsorship: National Library for Health (NHS Information Authority)
Resumo:
Schrijver, C.J. and Brown, D.S., 2000, Oscillations in the magnetic field of the solar corona in response to flares near the photosphere, Astrophysical Journal, 537, L69-L72. Sponsorship: PPARC
Resumo:
Listening to children in the field of education: experience in Wales, (2007) 19 Child and Family Law Quarterly 161-182 pp.161-182 RAE2008
Resumo:
http://www.archive.org/details/westchinamiss00unknuoft
Resumo:
A new science curriculum was introduced to primary schools in the Republic of Ireland in 2003. This curriculum, broader in scope than its 1971 predecessor (Curaclam na Bunscoile, 1971), requires teachers at all levels of primary school to teach science. A review carried out in 2008 of children’s experiences of this curriculum found that its implementation throughout the country was uneven. This finding, together with the increasing numbers of teachers who were requesting support to implement this curriculum, suggested the need for a review of Irish primary teachers’ needs in the area of science. The research study described in this thesis was undertaken to establish the extent of Irish primary teachers’ needs in the area of science by conducting a national survey. The data from this survey, together with data from international studies, were used to develop a theoretical framework for a model of Continuing Professional Development (CPD). This theoretical framework was used to design the Whole- School, In-School (WSIS) CPD model which was trialled in two case-study schools. The participants in these ‘action-research’ case-studies acted as co-researchers, who contributed to the development and evolution of the CPD model in each school. Analysis of the data gathered as part of the evaluation of the Whole-School, In- School (WSIS) model of CPD found an improved experience of science for children and improved confidence for teachers teaching at all levels of the primary school. In addition, a template for the establishment of a culture of collaborative CPD in schools has been developed from an analysis of the data
Resumo:
Published Version
Resumo:
© Institute of Mathematical Statistics, 2014.Motivated by recent findings in the field of consumer science, this paper evaluates the causal effect of debit cards on household consumption using population-based data from the Italy Survey on Household Income and Wealth (SHIW). Within the Rubin Causal Model, we focus on the estimand of population average treatment effect for the treated (PATT). We consider three existing estimators, based on regression, mixed matching and regression, propensity score weighting, and propose a new doubly-robust estimator. Semiparametric specification based on power series for the potential outcomes and the propensity score is adopted. Cross-validation is used to select the order of the power series. We conduct a simulation study to compare the performance of the estimators. The key assumptions, overlap and unconfoundedness, are systematically assessed and validated in the application. Our empirical results suggest statistically significant positive effects of debit cards on the monthly household spending in Italy.
Resumo:
This article argues that Irish “traditional” music is modern in its form and history, and explores the ramifications of this thesis for understanding of the peculiarities of Irish modernity and identity. The article exhaustively surveys the historiography of Irish traditional music and uniquely interprets this literature in relation to competing conceptions of identity and modernity articulated by Taylor, Appiah and Žižek. It also interprets Irish traditional music in relation to conceptions of Irish modernity articulated in a wide range of disciplines within Irish studies. Reflecting on the author’s lifelong engagement with traditional music performance, the article argues that the resilience of traditional music within the broader culture is connected to the peculiar character of Irish modernity, and that it suffers from problems of aesthetic exhaustion shared by much modern art in the contemporary conjuncture.