Complexity of inferences in polytree-shaped semi-qualitative probabilistic networks

Semi-qualitative probabilistic networks (SQPNs) merge two important graphical model formalisms: Bayesian networks and qualitative probabilistic networks. They provade a very Complexity of inferences in polytree-shaped semi-qualitative probabilistic networks and qualitative probabilistic networks. They provide a very general modeling framework by allowing the combination of numeric and qualitative assessments over a discrete domain, and can be compactly encoded by exploiting the same factorization of joint probability distributions that are behind the bayesian networks. This paper explores the computational complexity of semi-qualitative probabilistic networks, and takes the polytree-shaped networks as its main target. We show that the inference problem is coNP-Complete for binary polytrees with multiple observed nodes. We also show that interferences can be performed in time linear in the number of nodes if there is a single observed node. Because our proof is construtive, we obtain an efficient linear time algorithm for SQPNs under such assumptions. To the best of our knowledge, this is the first exact polynominal-time algorithm for SQPn. Together these results provide a clear picture of the inferential complexity in polytree-shaped SQPNs.

Overview of semi-sinusoidal stellar variability with the CoRoT satellite

Context. To date, the CoRoT space mission has produced more than 124 471 light curves. Classifying these curves in terms of unambiguous variab ility behavior is mandatory for obtaining an unbi ased statistical view on th eir controlling root-causes. Aims. The present study provides an overview of semi-sinusoidal light curves observed by the CoRoT exo-field CCDs. Methods. We selected a sample of 4206 light curves presenting well-defined semi-si nusoidal signatures. Th e variability periods were computed based on Lomb-Scargle periodograms, harmonic fits, and visual inspection. Results. Color–period diagrams for the present sample show the trend of an increase of the variability periods as long as the stars evolve. This evolutionary behavior is also noticed when comparing the period distribution in the Galactic center and anti-center directions. These aspect s indicate a compatibility with stellar rotation, although more inform ation is needed to confirm their root- causes. Considering this possi bility, we identified a subset of th ree Sun-like candidates by their photometric peri od. Finally, the variability period versus color diagr am behavior was found to be highly depe ndent on the reddening correction.

Diagnósticos de enfermagem em cuidadores de crianças com fissuras orofaciais e anomalias relacionadas internadas em unidade semi-intensiva

Objetivo: Identificar os diagnósticos de enfermagem em cuidadores de crianças com fissura orofaciais e anomalias relacionadas, internadas em unidade de cuidado semi-intensivo. Método: Estudo prospectivo, realizado na unidade de terapia semi-intensiva do Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo, nos meses de maio e junho de 2013. A amostra constou de 20 cuidadores. O critério de inclusão foi à adesão. Por meio da entrevista estruturada, os participantes foram avaliados em dois momentos distintos: na internação da criança e na alta hospitalar. Os diagnósticos foram formalizados segundo a taxonomia da NANDAInternacional, com enfoque psicossocial. Resultados: A amostra foi composta exclusivamente por mães, com idade média de 28,35 anos, ensino médio completo (60%), classe social média (60%), com união estável (75%) e moradia própria (75%). No momento da internação prevaleceram: o domínio papéis e relacionamentos (22%); a classe papéis do cuidador (85%), e os DE: tensão do papel de cuidador (100%), ansiedade (100%), disposição para o conhecimento aumentado (85%), disposição para controle aumentado do regime terapêutico (80%) e padrão de sono prejudicado (55%). No momento da alta prevaleceram: o domínio enfrentamento/tolerância ao estresse (33%); a classe respostas de enfrentamento (72%), e os DE: disposição para maternidade melhorada (50%), disposição para enfrentamento aumentada (50%), disposição para enfrentamento familiar aumentado (50%). Conclusão: Embora inicialmente os cuidadores tenham apresentado estresse, possivelmente devido à necessidade do aprendizado para a manutenção dos cuidados após a alta hospitalar, evidenciou-se posteriormente uma progressão em relação à aceitação situacional/enfrentamento.

A semi-supervised classification technique based on interacting forces

Semi-supervised learning is a classification paradigm in which just a few labeled instances are available for the training process. To overcome this small amount of initial label information, the information provided by the unlabeled instances is also considered. In this paper, we propose a nature-inspired semi-supervised learning technique based on attraction forces. Instances are represented as points in a k-dimensional space, and the movement of data points is modeled as a dynamical system. As the system runs, data items with the same label cooperate with each other, and data items with different labels compete among them to attract unlabeled points by applying a specific force function. In this way, all unlabeled data items can be classified when the system reaches its stable state. Stability analysis for the proposed dynamical system is performed and some heuristics are proposed for parameter setting. Simulation results show that the proposed technique achieves good classification results on artificial data sets and is comparable to well-known semi-supervised techniques using benchmark data sets.

Monte Carlo Semi-Empirical Model for Si(Li) X-Ray Detector: Differences between Nominal and Fitted Parameters.

A detailed characterization of a X-ray Si(Li) detector was performed to obtain the energy dependence of efficiency in the photon energy range of 6.4 - 59.5 keV. which was measured and reproduced by Monte Carlo (MC) simulations. Significant discrepancies between MC and experimental values were found when lhe manufacturer parameters of lhe detector were used in lhe simulation. A complete Computerized Tomagraphy (CT) detector scan allowed to find the correct crystal dimensions and position inside the capsule. The computed efficiencies with the resulting detector model differed with the measured values no more than 10% in most of the energy range.