43,958 research outputs found
Estimative for the size of the compactification radius of a one extra dimension Universe
In this work, we use the Casimir effect to probe the existence of one extra
dimension. We begin by evaluating the Casimir pressure between two plates in a
manifold, and then use an appropriate statistical analysis in
order to compare the theoretical expression with a recent experimental data and
set bounds for the compactification radius
Emergentism and musicology: an alternative perspective to the understanding of dissonance.
In this paper we develop an approach to musicology within the
discussion of emergentism. First of all, we claim that some theories of
musicology could be insufficient in describing and explaining musical
phenomena when emergent properties are not taken into account. Actually,
musicology usually considers just syntactical elements, structures and
processes and puts only a little emphasis, if any, over perceptual aspects of
human hearing. On the other hand, recent research efforts are currently being
directed towards an understanding of the emergent properties of auditory
perception, especially in fields such as cognitive science. Such research leads
to other views concerning old issues in musicology and could create a fruitful
approach, filling the gap between musicology and auditory perception
Improving Small Object Proposals for Company Logo Detection
Many modern approaches for object detection are two-staged pipelines. The
first stage identifies regions of interest which are then classified in the
second stage. Faster R-CNN is such an approach for object detection which
combines both stages into a single pipeline. In this paper we apply Faster
R-CNN to the task of company logo detection. Motivated by its weak performance
on small object instances, we examine in detail both the proposal and the
classification stage with respect to a wide range of object sizes. We
investigate the influence of feature map resolution on the performance of those
stages.
Based on theoretical considerations, we introduce an improved scheme for
generating anchor proposals and propose a modification to Faster R-CNN which
leverages higher-resolution feature maps for small objects. We evaluate our
approach on the FlickrLogos dataset improving the RPN performance from 0.52 to
0.71 (MABO) and the detection performance from 0.52 to 0.67 (mAP).Comment: 8 Pages, ICMR 201
Divergência genética em população pré-selecionada de bacuri (Platonia insignis).
Os frutos da Amazônia têm despertado grande interesse nos últimos anos, tanto em nível nacional quanto internacional em decorrência dos seus sabores exóticos, por apresentarem altos teores de vitaminas e antioxidantes e pelo aproveitamento de suas polpas no agronegócio e na indústria farmacêutica (FERNANDES et al., 2003; FRAZON, 2004). As demandas do mercado para a polpa do bacuri são semelhantes às do açaí e do cupuaçu, em que se verifica um evidente conflito entre a oferta natural e a crescente pressão da demanda dessas fruteiras devido sua sazonalidade (MENEZES et al., 2012). Os programas de melhoramento precisam se adequar e ser direcionados para atender as especificidades das diversas regiões e assim suprir as demandas de mercado e as restrições de produção (BATISTA, 2013). Em muitas situações, principalmente naquelas voltadas para fins de melhoramento genético, têm sido comum o estudo da diversidade genética com a finalidade de identificar genitores adequados ao cruzamento tendo em vista a obtenção de híbridos de maiores efeitos heteróticos que proporcionem maior segregação em recombinações e possibilitem o aparecimento de transgressivos (CRUZ et al., 2011). O bacuri apresenta flores perfeitas de tamanho grande, assim, a emasculação e os cruzamentos controlados se darão de maneira relativamente simples entre os genitores geneticamente divergentes, para a obtenção dos híbridos (progênies) do segundo ciclo de seleção recorrente. O objetivo deste trabalho foi determinar os grupos geneticamente divergentes entre genótipos de bacuri pré-selecionados para os atributos agrotecnológicos
Non-Gaussian two-mode squeezing and continuous variable entanglement of linearly and circularly polarized light beams interacting with cold atoms
We investigate how entangled coherent states and superpositions of low
intensity coherent states of non-Gaussian nature can be generated via
non-resonant interaction between either two linearly or circularly polarized
field modes and an ensemble of X-like four-level atoms placed in an optical
cavity. We compare our results to recent experimental observations and argue
that the non-Gaussian structure of the field states may be present in those
systems.Comment: 10 pages, 7 figures, replaced with final published versio
Multimode Hong-Ou-Mandel interference
We consider multimode two-photon interference at a beam splitter by photons
created by spontaneous parametric down-conversion. The resulting interference
pattern is shown to depend upon the transverse spatial symmetry of the pump
beam. In an experiment, we employ the first-order Hermite-Gaussian modes in
order to show that, by manipulating the pump beam, one can control the
resulting two-photon interference behavior. We expect these results to play an
important role in the engineering of quantum states of light for use in quantum
information processing and quantum imaging.Comment: 4 pages, 6 figures, submitted to PR
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