26,829 research outputs found
A New Perspective on the Nonextremal Enhancon Solution
We discuss the nonextremal generalisation of the enhancon mechanism. We find
that the nonextremal shell branch solution does not violate the Weak Energy
Condition when the nonextremality parameter is small, in contrast to earlier
discussions of this subject. We show that this physical shell branch solution
fills the mass gap between the extremal enhancon solution and the nonextremal
horizon branch solution.Comment: 10 pages, 3 figures, reference adde
Measures of metacognition on signal-detection theoretic models
Analysing metacognition, specifically knowledge of accuracy of internal perceptual,
memorial or other knowledge states, is vital for many strands of psychology, including
determining the accuracy of feelings of knowing, and discriminating conscious from
unconscious cognition. Quantifying metacognitive sensitivity is however more challenging
than quantifying basic stimulus sensitivity. Under popular signal detection theory (SDT)
models for stimulus classification tasks, approaches based on type II receiver-operator
characteristic (ROC) curves or type II d-prime risk confounding metacognition with
response biases in either the type I (classification) or type II (metacognitive) tasks. A new
approach introduces meta-dâ˛: the type I d-prime that would have led to the observed type
II data had the subject used all the type I information. Here we (i) further establish the
inconsistency of the type II d-prime and ROC approaches with new explicit analyses of
the standard SDT model, and (ii) analyse, for the first time, the behaviour of meta-dâ˛
under non-trivial scenarios, such as when metacognitive judgments utilize enhanced or
degraded versions of the type I evidence. Analytically, meta-dⲠvalues typically reflect the
underlying model well, and are stable under changes in decision criteria; however, in
relatively extreme cases meta-dⲠcan become unstable. We explore bias and variance of
in-sample measurements of meta-dⲠand supply MATLAB code for estimation in general
cases. Our results support meta-dⲠas a useful measure of metacognition, and provide
rigorous methodology for its application. Our recommendations are useful for any
researchers interested in assessing metacognitive accuracy
Granger causality analysis in neuroscience and neuroimaging
No description supplie
An analysis of imagery in listening to orchestral music in grades six and seven
Thesis (M.A.)--Boston Universit
Pathos: a web facility that uses metabolic maps to display experimental changes in metabolites identified by mass spectrometry
This work describes a freely available web-based facility which can be used to analyse raw or processed mass spectrometric data from metabolomics experiments and display the metabolites identified â and changes in their experimental abundance â in the context of the metabolic pathways in which they occur. The facility, Pathos (http://motif.gla.ac.uk/Pathos/), employs Java servlets and is underpinned by a relational database populated from the Kyoto Encyclopaedia of Genes and Genomes (KEGG). Input files can contain either raw m/z values from experiments conducted in different modes, or KEGG or MetaCyc IDs assigned by the user on the basis of the m/z values and other criteria. The textual output lists the KEGG pathways on an XHTML page according to the number of metabolites or potential metabolites that they contain. Filtering by organism is also available. For metabolic pathways of interest, the user is able to retrieve a pathway map with identified metabolites highlighted. A particular feature of Pathos is its ability to process relative quantification data for metabolites identified under different experimental conditions, and to present this in an easily comprehensible manner. Results are colour-coded according to the degree of experimental change, and bar charts of the results can be generated interactively from either the text listings or the pathway maps. The visual presentation of the output from Pathos is designed to allow the rapid identification of metabolic areas of potential interest, after which particular results may be examined in detail
The identification of cloud types in LANDSAT MSS images
The author has identified the following significant results. Five general families of clouds were identified: cumulonimbiform, cumuliform, stratiform, stratocumuliform, and cirriform. Four members of this five-fold primary division of clouds were further divided into a number of subgroups. The MSS observed and recorded earth radiation in four different wavebands. Two of these bands (4 and 5) image in the visible portion of the electromagnetic spectrum, while the others (6 and 7) image the short wave portion, or just into the infrared. The main differences between the appearances of clouds in the four wavebands are related to the background brightness of land and sea surfaces
Comparisons of cloud cover evaluated from LANDSAT imagery and meteorological stations across the British Isles
The author has identified the following significant results. This stage of the study has confirmed the initial supposition that LANDSAT data could be analyzed to provide useful data on cloud amount, and that useful light would be thrown thereby on the performance of the ground observer of this aspect of the state of the sky. This study, in comparison with previous studies of a similar nature using data from meteorological satellites, has benefited greatly from the much higher resolution data provided by LANDSAT. This has permitted consideration of not only the overall performance of the surface observer in estimating total cloud cover, but also his performance under different sky conditions
Temperature dependent nonlinear metal matrix laminae behavior
An analytical method is described for computing the nonlinear thermal and mechanical response of laminated plates. The material model focuses upon the behavior of metal matrix materials by relating the nonlinear composite response to plasticity effects in the matrix. The foundation of the analysis is the unidirectional material model which is used to compute the instantaneous properties of the lamina based upon the properties of the fibers and matrix. The unidirectional model assumes that the fibers properties are constant with temperature and assumes that the matrix can be modelled as a temperature dependent, bilinear, kinematically hardening material. An incremental approach is used to compute average stresses in the fibers and matrix caused by arbitrary mechanical and thermal loads. The layer model is incorporated in an incremental laminated plate theory to compute the nonlinear response of laminated metal matrix composites of general orientation and stacking sequence. The report includes comparisons of the method with other analytical approaches and compares theoretical calculations with measured experimental material behavior. A section is included which describes the limitations of the material model
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