10,234 research outputs found
An analysis of the general content, grade placement, and philosophy of state courses of study in arithmetic for grades one to six.
Thesis (Ed.M.)--Boston Universit
A hybrid technique for face detection in color images
In this paper, a hybrid technique for face detection in color images is presented. The proposed technique combines three analysis models, namely skin detection, automatic eye localization, and appearance-based face/nonface classification. Using a robust histogram-based skin detection model, skin-like pixels are first identified in the RGB color space. Based on this, face bounding-boxes are extracted from the image. On detecting a face bounding-box, approximate positions of the candidate mouth feature points are identified using the redness property of image pixels. A region-based eye localization step, based on the detected mouth feature points, is then applied to face bounding-boxes to locate possible eye feature points in the image. Based on the distance between the detected eye feature points, face/non-face classification is performed over a normalized search area using the Bayesian discriminating feature (BDF) analysis method. Some subjective evaluation results are presented on images taken using digital cameras and a Webcam, representing both indoor and outdoor scenes
Why Two Renormalization Groups are Better than One
The advantages of using more than one renormalization group (RG) in problems
with more than one important length scale are discussed. It is shown that: i)
using different RG's can lead to complementary information, i.e. what is very
difficult to calculate with an RG based on one flow parameter may be much more
accessible using another; ii) using more than one RG requires less physical
input in order to describe via RG methods the theory as a function of its
parameters; iii) using more than one RG allows one to solve problems with more
than one diverging length scale. The above points are illustrated concretely in
the context of both particle physics and statistical physics using the
techniques of environmentally friendly renormalization. Specifically, finite
temperature theory, an Ising-type system in a film geometry, an
Ising-type system in a transverse magnetic field, the QCD coupling constant at
finite temperature and the crossover between bulk and surface critical
behaviour in a semi-infinite geometry are considered.Comment: 17 pages LaTex; to be published in the Proceedings of RG '96, Dubn
Comment on ``Can Disorder Induce a Finite Thermal Conductivity in 1D Lattices?''
In a recent paper [Phys. Rev. Lett. 86, 63 (2001)], Li et al have reported
that the nonequilibrium heat conducting steady state of a disordered harmonic
chain is not unique. In this comment we point out that for a large class of
stochastic heat baths the uniqueness of the steady state can be proved, and
therefore the findings of Li et al could be either due to their use of
deterministic heat baths or insufficient equilibration times in the
simulations. We give a simple example where the uniquness of the steady state
can be explicitly demonstrated.Comment: 1 page, 1 figure, accepted for publication in Phys. Rev. Let
An interactive and multi-level framework for summarising user generated videos
We present an interactive and multi-level abstraction framework for user-generated video (UGV) summarisation, allowing a user the flexibility to select a summarisation criterion out of a number of methods provided by the system. First, a given raw video is segmented into shots, and each shot is further decomposed into sub-shots in line with the change in dominant camera motion. Secondly, principal component analysis (PCA) is applied to the colour representation of the collection of sub-shots, and a content map is created using the first few components. Each sub-shot is represented with a ``footprint'' on the content map, which reveals its content significance (coverage) and the most dynamic segment. The final stage of abstraction is
devised in a user-assisted manner whereby a user is able to specify a desired summary length, with options to interactively perform abstraction at different granularity of visual comprehension. The results obtained show the potential benefit in significantly alleviating the burden of
laborious user intervention associated with conventional video editing/browsing
Origins of choice-related activity in mouse somatosensory cortex.
During perceptual decisions about faint or ambiguous sensory stimuli, even identical stimuli can produce different choices. Spike trains from sensory cortex neurons can predict trial-to-trial variability in choice. Choice-related spiking is widely studied as a way to link cortical activity to perception, but its origins remain unclear. Using imaging and electrophysiology, we found that mouse primary somatosensory cortex neurons showed robust choice-related activity during a tactile detection task. Spike trains from primary mechanoreceptive neurons did not predict choices about identical stimuli. Spike trains from thalamic relay neurons showed highly transient, weak choice-related activity. Intracellular recordings in cortex revealed a prolonged choice-related depolarization in most neurons that was not accounted for by feed-forward thalamic input. Top-down axons projecting from secondary to primary somatosensory cortex signaled choice. An intracellular measure of stimulus sensitivity determined which neurons converted choice-related depolarization into spiking. Our results reveal how choice-related spiking emerges across neural circuits and within single neurons
A sociometric study of social acceptance in a second grade before and after a remedial program
Thesis (Ed.M.)--Boston Universit
How has neuroscience affected lay understandings of personhood? A review of the evidence.
The prominence of neuroscience in the public sphere has escalated in recent years, provoking questions about how the public engages with neuroscientific ideas. Commentaries on neuroscience's role in society often present it as having revolutionary implications, fundamentally overturning established beliefs about personhood. The purpose of this article is to collate and review the extant empirical evidence on the influence of neuroscience on commonsense understandings of personhood. The article evaluates the scope of neuroscience's presence in public consciousness and examines the empirical evidence for three frequently encountered claims about neuroscience's societal influence: that neuroscience fosters a conception of the self that is based in biology, that neuroscience promotes conceptions of individual fate as predetermined, and that neuroscience attenuates the stigma attached to particular social categories. It concludes that many neuroscientific ideas have assimilated in ways that perpetuate rather than challenge existing modes of understanding self, others and society
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