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Search Results: 1 - 10 of 12757 matches for " Ant?nio Ocimar;Gielow "
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Calibra??o do "simplified simple biosphere model - SSiB" para áreas de pastagem e floresta na Amaz?nia com dados do LBA
Correia, Francis Wagner Silva;Alvalá, Regina Célia dos Santos;Manzi, Antnio Ocimar;Gielow, Ralf;Kubota, Paulo Yoshio;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000200017
Abstract: the parameters of the simplified simple biosphere model - ssib were validated and subsequently calibrated for the fazenda nossa senhora aparecida (62o22'w; 10o45's) pasture site and the reserva biológica do jaru (62o22'w; 10o45's) forest site, both located in the state of rond?nia. micrometeorological and hydrological data collected during the dry period of 2001, as part of the large-scale biosphere-atmosphere experiment in amazonia - lba, were used. the results showed that the model simulated well the net radiation, both at the pasture and at the forest. the latent heat flux was super-estimated in both sites. the model sub-estimated the sensible heat flux at the pasture and at the forest, mainly during the night period; notwithstanding, the values for the forest were nearer to the observed ones. with the calibrated parameters, the model generated better estimations of the latent and the sensible heat fluxes, thus better representing the energy partition both at the forest and at the pasture.
Semi-Empirical Oscillator Strengths and Lifetimes for the P IV Spectrum  [PDF]
Antnio Jamil Mania
Spectral Analysis Review (SAR) , 2017, DOI: 10.4236/sar.2017.54005
Abstract: In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of each energy level. With the existing data from several authors that contributed to the spectrum using different light sources, and optimizing the electrostatic parameters by a least-squares procedure when replacing the theoretical values by the experimental ones in the energy matrices, one obtains closer values and according to the observations for the intensities, and also of the lifetimes closer to those that would be obtained experimentally.
Economic Freedom and Foreign Direct Investment: How Different are the MENA Countries from the EU  [PDF]
José CAETANO, António CALEIRO
iBusiness (IB) , 2009, DOI: 10.4236/ib.2009.12010
Abstract: The risk perceived by investors is crucial in the decision to invest, in particular when it concerns a foreign country. The risk associated to any (foreign) investment is a multi-faceted element given that it reflects many aspects that are relevant to (foreign) investors, such as the level of transparency, corruption, rule of law, governance, etc. In this paper we consider the level of economic freedom, as provided by the “Heritage Foundation”, for the most recent years, in order to analyse how is this measure of risk related to the inward foreign direct investment performance index, as provided by the UNCTAD. Given the subjectivity of risk an appropriate methodology consists on using fuzzy logic clustering, which is applied in the paper in order to verify how different the MENA region is from the set of EU-member states. The results show that economic freedom and inward FDI are positively associated, in particular in the cluster of countries that present a higher economic freedom. Of particular interest is the result that some MENA countries belong to the same cluster of most of the EU-countries.
Megalithic Constructions Discovered in the Azores, Portugal  [PDF]
António Félix Rodrigues
Archaeological Discovery (AD) , 2015, DOI: 10.4236/ad.2015.32006
Abstract: The oldest cave art known is of prehistoric origin, dating back to approximately 40,000 years ago in both Asia and Europe. The megalithic constructions in Western Europe and the Mediterranean Region took place mainly in the Neolithic and continued until the Chalcolithic and Bronze Age. The Azores Islands did not seem to have been occupied before the arrival of the Portuguese navigators in the XVth century. Because of that, it was not expected that megalithic structures would be found, or structures that resembled megalithic tombs and rock art in the Azores Islands, geographically located in the Center of the North Atlantic, at 1500 km west of Lisbon (Portugal) and about 1900 km southeast of Newfoundland (Canada). These findings seem to be, historically, a paradox. In a first moment, an oral presentation was made about these findings by the author at the 16th Annual Mediterranean Studies Association Congress, and after that, a field trip took place with the archeologists present at the stated Congress. The perplexity was the dominant conduct of the guests, and some hypotheses that certain archaeologists mentioned were evolved versions which had not been empirically corroborated. Afterwards, new findings were registered at Grota do Medo site, helping to make clear that larger stones had been used to construct structures or monuments. The rock art surrounding the megalithic constructions in the Azores also has similarities with those found in Europe. If these findings belong to the Bronze Age or Iron Age, it can reopen new scientific questions about ancient mid-Atlantic crossings. The present article tries to establish ties among the megalith constructions found in the Azores with those known in Europe.
Spondylodiscitis Caused by Streptococcus dysgalactiae Subspecies Equisimilis: A Case Report of an Increasingly Recognized Pathogenic Organism  [PDF]
Sara Be?a, Sandra Xerinda, António Sarmento
Advances in Infectious Diseases (AID) , 2014, DOI: 10.4236/aid.2014.41004
Abstract:

Streptococcus dysgalactiae subspecies equisimilis (SDSE) is a β-hemolytic Streptococcus that possesses genetic and clinical similarities to Streptococcus pyogenes. It is increasingly recognized as the etiological microorganism of invasive diseases. We report a case of a 74-year-old male who was admitted to this hospital with lower back and neck pain and infected with leg ulcer. The diagnosis of spondylodiscitis C2-C3 and L1-L3 caused by Streptococcus dysgalactiae subsp. equisimilis was made. The present case demonstrates the risk of older patients of developing invasive disease upon skin infection with Streptococcus dysgalactiae subsp. equisimilis, even when risk factors are absent or well controlled (as was diabetes mellitus in this case), suggesting that the pathogenic potential of SDSE should not be underestimated.

Numerical Uncertainty and Its Implications  [PDF]
António F. Rodrigues, Nuno O. Martins
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.23004
Abstract:

A scrutiny of the contributions of key mathematicians and scientists shows that there has been much controversy (throughout the development of mathematics and science) concerning the use of mathematics and the nature of mathematics too. In this work, we try to show that arithmetical operations of approximation lead to the existence of a numerical uncertainty, which is quantic, path dependent and also dependent on the number system used, with mathematical and physical implications. When we explore the algebraic equations for the fine structure constant, the conditions exposed in this work generate paradoxical physical conditions, where the solution to the paradox may be in the fact that the fine-structure constant is calculated through different ways in order to obtain the same value, but there is no relationship between the fundamental physical processes which underlie the calculations, since we are merely dealing with algebraic relations, despite the expressions having the same physical dimensions.

Fast Fading Channel Neural Equalization Using Levenberg-Marquardt Training Algorithm and Pulse Shaping Filters  [PDF]
Tiago Mota, Jorgean Leal, Antnio Lima
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2014, DOI: 10.4236/ijcns.2014.72008
Abstract:

Artificial Neural Network (ANN) equalizers have been successfully applied to mitigate Inter symbolic Interference (ISI) due to distortions introduced by linear or nonlinear communication channels. The ANN architecture is chosen according to the type of ISI produced by fixed, fast or slow fading channels. In this work, we propose a combination of two techniques in order to minimize ISI yield by fast fading channels, i.e., pulse shape filtering and ANN equalizer. Levenberg-Marquardt algorithm is used to update the synaptic weights of an ANN comprise only by two recurrent perceptrons. The proposed system outperformed more complex structures such as those based on Kalman filtering approach.

The Impact of Using the Interactive Multimedia Book on Mathematics Learning: A Focus on 7th Grade Students Performance  [PDF]
Guedes António Caetano, Milton Zaro
Creative Education (CE) , 2018, DOI: 10.4236/ce.2018.915185
Abstract: Two experiments were developed to verify how the use of interactive multimedia books improves students’ school performance in 7th grade math learning. The aim of the study was to compare the performance of students using the Multimedia Interactive Book with non-students in 7th grade mathematics at a primary school in Mozambique, and was guided in two hypotheses. The null hypothesis was: the use of the interactive multimedia book in mathematics learning does not improve students performance and the alternative hypothesis was: the use of the interactive multimedia book in mathematics learning improves students performance. The learning object was developed from the free web tool Edilim and 44 students aged between 11 and 17 participated in the study. The first experiment had 20 hours of study while the second experiment was 60 hours of study, totalling 80 hours of study. To assess the participants’ cognitive development stage, the clinical method was used: operative tests of number, fluid and length preservation. The results of both experiments indicate that the use of the interactive multimedia book does not improve students’ performance in math learning, corroborating with studies and theses that warn that the use of computers and multimedia resources does not improve students’ performance in math learning.
A model of bone adaptation as a topology optimization process with contact  [PDF]
António Andrade-Campos, António Ramos, José A. Sim?es
Journal of Biomedical Science and Engineering (JBiSE) , 2012, DOI: 10.4236/jbise.2012.55030
Abstract: Topology optimization is presently used in most diverse scientific, technologic and industrial areas, including biomechanics. Bone remodelling models and structural optimization has mutually provided inspiration for new developments in biomechanics and biomedicine. Considering that bone has the ability to adapt its internal structure to mechanical loading (Wolff’s law and Roux’s paradigm), it is possible to model the behaviour of the bone structure by the use of a topology optimization methodology whose optimization variables can be the relative densities and the orthotropic directions. In this work, the internal bone adaptation of a proximal femur is considered. The bone-remodelling scheme is numerically described by a time-dependent evolutionary procedure with anisotropic material parameters. The remodelling rate equation is obtained from the structural optimization task of maximizing the stiffness subject to a biological cost associated with metabolic maintenance of bone tissue in time. The situation of multiple load conditions is considered for a three-dimensional finite element model of the proximal femur. The bone density distribution of a real femur is used as the initial design for the onset of the remodelling mechanism. Examples of bone adaptation resulting from load changes are presented. The three-dimensional finite element model of the proximal femur with initial bone density distribution was adapted to implant a cementless stem. A remeshing technique is used to assign the bone relative density distribution to the new geometry and mesh. The time adaptation of the bone is assessed considering contact with friction at the bone-stem interface. Results of bone density evolution and osteointegration distribution are obtained.
Self-Learning Skills Perceived in Communities of Inquiry of Portuguese Higher Education Students  [PDF]
José António Moreira, António Gomes Ferreira, Ana Cristina Almeida
Psychology (PSYCH) , 2013, DOI: 10.4236/psych.2013.45066
Abstract:

The purpose of this study was to report evidence obtained in Communities of Inquiry (CoI) as framed by the work of Garrison, Anderson and Archer (2000) that was carried out in different groups, and identify the emergent learning skills of its students. The study comprised 510 undergraduate students enrolled in blended online courses offered through Moodle platform during one semester. It considered students from different Portuguese schools, of University and Polytechnic in Health, Education and Psychology Courses. Moreira and Almeida (2011) have suggested that CoI framework is a valid, reliable, and efficient measure of its dimensions within the Portuguese population. Assuming the CoI survey as a useful evaluation tool for providing feedback about the effectiveness of online courses in the construction of effective learning communities, we’ve studied the skills students recognize they acquire in virtual environments of learning, using the adapted Self-Learning Competence Scale (Lima-Santos, Rurato, & Faria, 2000). We’ve concluded that in both institutions, University and Polytechnic, relevant learning experiences have been fostered, towards the emergence of communities of inquiry, in which the students perceived that they have developed self-learning competences.

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