23,459 research outputs found
Stimulated emission and excited-state absorption at room temperature on the 550 nm-laser transition in Er3+ doped YAlO3
A pump- and probe-beam technique is used for measuring time-resolved and cw-pumped excited-state absorption (ESA) and stimulated-emission (SE) spectra of Er3+:YAlO3 with high resolution. In combination with absorption and fluorescence spectra, detailed information on the wavelengths and cross-sections of ESA and SE at the 550 nm laser transition is provided
Block-Transitive Designs in Affine Spaces
This paper deals with block-transitive - designs in affine
spaces for large , with a focus on the important index case. We
prove that there are no non-trivial 5- designs admitting a
block-transitive group of automorphisms that is of affine type. Moreover, we
show that the corresponding non-existence result holds for 4- designs,
except possibly when the group is one-dimensional affine. Our approach involves
a consideration of the finite 2-homogeneous affine permutation groups.Comment: 10 pages; to appear in: "Designs, Codes and Cryptography
Prime diagnosticity in short-term repetition priming: Is primed evidence discounted, even when it reliably indicates the correct answer?
The authors conducted 4 repetition priming experiments that manipulated prime duration and prime diagnosticity in a visual forced-choice perceptual identification task. The strength and direction of prime diagnosticity produced marked effects on identification accuracy, but those effects were resistant to subsequent changes of diagnosticity. Participants learned to associate different diagnosticities with primes of different durations but not with primes presented in different colors. Regardless of prime diagnosticity, preference for a primed alternative covaried negatively with prime duration, suggesting that even for diagnostic primes, evidence discounting remains an important factor. A computational model, with the assumption that adaptation to the statistics of the experiment modulates the level of evidence discounting, accounted for these results
Numerical Approach to Multi Dimensional Phase Transitions
We present an algorithm to analyze numerically the bounce solution of
first-order phase transitions. Our approach is well suited to treat phase
transitions with several fields. The algorithm consists of two parts. In the
first part the bounce solution without damping is determined, in which case
energy is conserved. In the second part the continuation to the physically
relevant case with damping is performed. The presented approach is numerically
stable and easily implemented.Comment: 18 pages, 8 figures; some comments, a reference and a table adde
An analysis of internally funded learning and teaching project evaluation in higher education
© 2016, © Emerald Group Publishing Limited. Purpose â In the higher education sector, the evaluation of learning and teaching projects is assuming a role as a quality and accountability indicator. The purpose of this paper is to investigate how learning and teaching project evaluation is approached and critiques alignment between evaluation theory and practice. Design/methodology/approach â The emergent realism paradigm provides the theoretical framework with a pragmatic approach to mixed-methods data collection. Thematic analysis was used to analyze the transcripts of interviews with 15 project leaders. Findings â Four key themes on project evaluation emerged: how evaluation is conceptualized, particularly the overlap, even conflation, between evaluation and research; capability building within the sector; resourcing in terms of time and money; and the role of an action-oriented approach to evaluation. The authors conclude that misalignment exists between evaluation theory and the practice of project evaluation and that this relationship can be further inhibited by a project leaderâs perception of evaluation. Practical implications â A series of strategies for developing capacity across the higher education sector for project evaluation are presented. These include the development and provision of: a time allocation for evaluation in future and ongoing project plans with procedures to revisit the project and assess impact; models of how to incorporate evaluation into the research cycle; constructive feedback on evaluation reports from the university funding body; and networking opportunities to disseminate learnings from project evaluations. Originality/value â This study focusses on the under-researched area of evaluation of learning and teaching projects in higher education, providing research-based evidence for strategies to develop sector capacity
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