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On the Singular Effects in the Relativistic Landau Levels in Graphene with a Disclination

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Communications in Theoretical Physics 2018年第12期69卷 817-822页

作者： Rosinildo f.do Nascimento Diego Cogollo Edilberto O.silva Moisés Rojas Cleverson filgueiras Instituto de fisica Universidade Federal de UberlandiaUberlandiaMGBrasil Unidade Academica de fisica Universidade Federal de Campina GrandePOB 1007158109-970Campina Grande-PB Brazil departamento de fisica Universidade Federal do Maranhao65085-580Sao Luis-MABrazil departamento de fisica Universidade Federal de LavrasCaixa Postal 303737200-000Lavras-MGBrazil

The effect of a pseudo Aharonov-Bohm(AB) magnetic field generated by a disclination on a two-dimensional electron gas in graphene is addressed in the continuum limit within the geometric approach. The influence of the coupling between the spinor fields and the singular conical curvature is investigated, which shows that singularities have pronounced impact in the Hall conductivity. Moreover, the degeneracy related to the Dirac valleys is broken for negative values of the angular momentum quantum numbers, ?, including ? ≡ 0. In this case, a Hall plateau develops at the null filling factor. Obtaining the Hall conductivity by summing over the positive and the negative ?′s, the null Landau level is recovered and the plateau at the null filling factor disappears. In any case, the standard plateaus, which are seen in a flat graphene are not obtained with these curvature and singular effects.

关键词： Landau Levels Hall conductivity Graphene Elastic deformations

Dynamic Analysis of Steel Platforms When Subjected to Mechanical Equipment-Induced Vibrations

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Journal of Civil Engineering and Architecture 2016年第10期10卷 1103-1113页

作者： Jose Guilherme S. da silva Ana Cristina C. f. Sieir~ Luis A. P. Simoes da silva Bruno D. Rimola Structural Engineering department (ESTR) State University of Rio de Janeiro (UERJ) Rio de Janeiro 20550-900 Brazil Civil Engineering Post-graduate Programme (PGECIV) State University of Rio de Janeiro (UERJ) Rio de Janeiro 20550-900Brazil Civil Engineering department University of Coimbra Coimbra 3030-788 Portugal

The competitive trends of the world market have long been forcing structural engineers to develop minimum weight and labour cost solutions. A direct consequence of this new design trend has been a considerable increase in problems related to undesired floor vibrations. for this reason, structural floor systems can become vulnerable to excessive vibrations that are produced by, for example, impacts due to mechanical equipment （e.g., rotating machinery）. This study investigates the dynamic behaviour of a production platform constructed of steel and located in the Santos Basin （Merluza field）, Sao Paulo/SP, Brazil, when subjected to impacts produced by mechanical equipment （rotating machinery）. The structural model consists of two steel decks with a total area of 1,915 m^2 （upper deck： 445 m^2, lower deck： 1,470 m^2） and supported by piles. A numerical analysis is performed to assess the dynamic impacts on the deck structure originating from the electrical generators and compressors. Based on the peak acceleration values obtained for the structure steady-state response, it is possible to evaluate the structural model performance in terms of human comfort, the maximum tolerances of the mechanical equipment and the vibration serviceability limit states of the structure.

关键词： Dynamic analysis steel structures production platforms human comfort structural behaviour computational modelling

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航空轮胎胎面胶配方

现代橡胶技术 2018年第2期44卷 31-40页

作者：文兴 José Carlos araujo da silva Aurélie TRIGUEL

本发明是有关航空轮胎的发明。本发明轮胎的胎面胶配方至少有一种二烯系橡胶、一种补强填充剂和一种交联体系。二烯系橡胶为乙烯、α-烯烃和非共轭二烯的三元聚合物。本发明轮胎可明显改善着陆性能,特别是可明显改善在非常高速下的轮胎... 详细信息

本发明是有关航空轮胎的发明。本发明轮胎的胎面胶配方至少有一种二烯系橡胶、一种补强填充剂和一种交联体系。二烯系橡胶为乙烯、α-烯烃和非共轭二烯的三元聚合物。本发明轮胎可明显改善着陆性能,特别是可明显改善在非常高速下的轮胎耐磨性。

关键词：航空轮胎胎面胶配方耐磨性

Health, Aging and Quality of Life: An Evaluation of Experience in family Health Unit through Popular Education

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Health 2014年第15期6卷 1959-1963页

作者： Cristina Katya torres Teixeira Mendes fabia Barbosa de Andrade danielle Nóbrega de Castro Maria do Socorro feitosa Alves Gilson de Vasconcelos torres Maria Adelaide Paredes Moreira Antonia Oliveira silva department of dentistry Federal University of Rio Grande do Norte Natal Brazil department of Nursing FACISA Federal University of Rio Grande do Norte Natal Brazil department of Nursing Federal University of Rio Grande do Norte Natal Brazil department of Public Health and Psychiatry Federal University of Paraíba Jo&atilde o Pessoa Brazil Municipal Health Jo&atilde o Pessoa Paraíba Brazil Nursing Federal University of Paraíba Jo&atilde o Pessoa Brazil Nursing Federal University of Rio Grande do Norte Natal Brazil

This study aims to assess the implementation of the Health, Aging and Quality of Life. The specific objectives were executed by conducting activities with the elderly through generative themes with an emphasis on health, aging and quality of life;evaluation of the experience of older people in Unity family Health with Popular Education;analyzing the evolution of indicators of health and quality of life of elderly patients after two years and ascertaining the effectiveness of Popular Education in the elderly group in the family Health Unit. This is an exploratory study approved by the Ethics and Research Committee UfPB/CCS, number 0598/08 held on Primary Health Care. The project consists of two lines of integrated activities: Group Active Ageing (GEA), which brings together seniors for addressing issues related to healthy aging and the Multidimensional Health Assessment and Quality of Life through the WHOQOL-BREf. The activities were built in fortnightly meetings from the dialogue where experiences are shared and collective needs. Thus, relevant topics were suggested for the group: guidelines on physical activity, nutrition, chronic disease prevention, self-esteem, among others, and group dynamics as body stretching, stretching exercises, respiratory, metabolic and relaxation. The observed results are the very satisfactions group, reported through testimonies and translated by the enthusiasm and diligence in participation. This project promoted a better bio-psycho-social development of the elderly, reinforcing its identity by promoting and facilitating the expression of their potential positive and arousing them to a better future life prospects and community socialization feelings.

关键词： Health Aging Quality of Life

detection of delayed Hypersensitivity to fonsecaea pedrosoi Metabolic Antigen （Chromomycin）in Healthy People in an Endemic Area

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Journal of Life Sciences 2013年第3期7卷 267-275页

作者： Conceiao de Maria Pedrozo e silva de Azevedo Antonio Augusto Moura da silva Sirlei Garcia Marques Oscar Brufia-Romero Gilnara fontinelle silval Cecilia silva de Lima flaivia Raquel femandes do Nascimento Maria Aparecida de Resende Stoianoff department of Medicine Federal University of Maranh6o S6o Luis City 65604010 Maranh6o Brazil department of Microbiology Federal University of Minas Gerais Belo Horizonte 31270901 Minas Gerais Brazil

The CBM （chromoblastomycosis） is a disease caused by dematiaceous fungi, which has the species fonsecaea pedrosoi as main agent. This fungus is found in warm and moist climates, characteristically found in the amazonic lands of the region, where its environmental isolation was once described. This research aimed to identify the healthy population exposed to agent f. pedrosoi in four villages located in the Legal Amazon. In order to clarify the risk factors for allergic immune exposure, a survey was conducted by the technique of delayed skin reaction （IDR） with the metabolic antigen （chromomycin） in 449 healthy individuals. The results showed that 14.9% （67 subjects） were IDR positive, with induration 〉 5 mm. Multivariate analysis with logistic regression for risk factors： living in the village of Z6 Pedro （municipality of Bacabeira in the state of Maranhao, Brazil）,

关键词： fonsecaeapedrosoi chromomycin risk factor.

Co-Creation in the Game Industry:A Case Study in a Brazilian developer

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Social Networking 2018年第1期7卷 63-78页

作者： Marcos Vinicius Cardoso Huoston Rodrigues Batista Ernani Marques da silva Marcos Antonio Gaspar Ivanir Costa fábio Luís falchi de Magalhaes Universidade Anhembi Morumbi Sao PauloBrazil Graduate Program in Informatics and Knowledge Management Universidade Nove de Julho(UNINOVE)Sao PauloBrazil

The objective of this work is to understand how the process of co-creation occurs within the creative industry of video games. for this, concepts of the creative industry, co-creation, information and communication technologies (ICTs) and innovation were studied. Since this is an exploratory and qualitative research, a single case study was chosen as a method. The analysis was done in a Brazilian company that develops games for mobile devices. The results show that the consumer (gamer) participates in value creation in the company’s products, mainly in the initial production stages. In the later phases, after the launch and other steps of the life cycle, although there is a relationship with the users, the joint creation of value is little explored by the organization. Also, it was verified that the co-creation process is supported by different information and communication tools, which provide agility to the process.

关键词： Co-Creation Empirical Studies Gaming Communities Information and Communication Technologies Innovation

Numerical Solution of the Upper-Convected Maxwell Model for Three-Dimensional free Surface flows

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Communications in Computational Physics 2009年第7期6卷 367-395页

作者： Murilo f.Tome Renato A.P.silva Cassio M.Oishi Sean McKee departamento de Matematica Aplicada e Estatıstica Instituto de Ciencias Matematicas e de Computa¸caoUniversidade de Sao PauloSao CarlosBrazil department of Mathematics University of StrathclydeGlasgowUK

This work presents a finite difference technique for simulating three-dimensional free surface flows governed by the Upper-Convected Maxwell(UCM)constitutive equation.A Marker-and-Cell approach is employed to represent the fluid free surface and formulations for calculating the non-Newtonian stress tensor on solid boundaries are *** complete free surface stress conditions are *** momentum equation is solved by an implicit technique while the UCM constitutive equation is integrated by the explicit Euler *** resulting equations are solved by the finite difference method on a 3D-staggered *** using an exact solution for fully developed flow inside a pipe,validation and convergence results are *** results include the simulation of the transient extrudate swell and the comparison between jet buckling of UCM and Newtonian fluids.

关键词： Viscoelastic flow Upper-Convected Maxwell finite difference free surface implicit techniques Marker-and-Cell

Charged Gravastar in a dark Energy Universe

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Journal of Modern Physics 2013年第6期4卷 869-878页

作者： C.f.C.Brandt R.Chan M.f.A.da silva P.Rocha departamento de fisica Teorica Instituto de FisicaUniversidade do Estado do Rio de JaneiroRua Sao Francisco Xavier 524MaracanaRio de Janeiro-RJBrasil Coordenacao de Astronomia e Astrofisica Observatorio NacionalRua General Jose Cristino77Sao CristovaoRio de JaneiroRJBrazil IST-Instituto Superior de Tecnologia de Paracambi FAETECRua Sebastiao de Lacerda s/nBairro da FabricaParacambiRJBrazil

Here we constructed a charged gravastar model formed by an interior de Sitter spacetime, a charged dynamical infinitely thin shell with an equation of state and an exterior de Sitter-Reissner-Nordstrom spacetime. We find that the presence of the charge is crucial to the stability of these structures. It can as much favor the stability of a bounded excursion gravastar, and still converting it in a stable gravastar, as make disappear a stable gravastar, depending on the range of the charge considered. There is also formation of black holes and, above certain values, the presence of the charge allows the formation of naked singularity. This is an important example in which a naked singularity emerges as a consequence of unstabilities of a gravastar model, which reinforces that gravastar is not an alternative model to black hole.

关键词： Gravastar Charge de Sitter-Reissner-Nordstrom Spacetime Black Hole Naked Singularity dark Energy

Proposed Relief Map of the Suitability of the Maranhão River Basin, Brazil, for Anthropogenic Use

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Journal of Geographic Information System 2016年第3期8卷 351-360页

作者： Valdir A. Steinke Ercilia torres Steinke Mario Diniz araujo Neto Maria Ligia Cassol Pinto University of Brasilia Brasília Brazil

In this paper, we proposed a method for mapping the suitability of land for intensive anthropogenic use in the Maranhao River Basin, in the state of Goiás, Brazil. We analyzed existing 1:250,000 maps of the local geology, drainage system topography and geomorphological features. We generated new information based on our analysis, including a compilation of basic morphometric data and a map of the slopes in the basin, which we used to construct the geomorphological suitability map of the watershed. Our results indicate that 40% of the study area can support intensive anthropogenic use;the remaining 60% of the basin area is categorized as “fragile” regarding the expansion of intensive land use.

关键词： Morphometry GIS Environmental Management Suitability of the Watershed Land Use Policy