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Hydrodynamics of the interceptor on a 2-D flat plate by CFD and experiments

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Journal of Hydrodynamics 2015年第6期27卷 919-933页

作者： mANSOORI m. fernandes A.C. Department of Naval and Ocean Engineering Federal University of Rio de Janeiro

Nowadays, the use of interceptor by both partial and total dynamic lift crafts is quite common. In this article, a lot of evidence is given regarding the effectiveness of interceptor. The interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. This study focuses on hydrodynamic effects of interceptors on a 2-D fiat plate based on both computational fluid dynamic （CFD） and experimental approaches. The Reynolds average Navier-Stokes （RANS） equations are used to model the flow around a fixed flat plate with an interceptor at different heights and attack angles. Based on finite volume method and SImPLE algorithm which uses static structures, this model can be analyzed and the RANS results can be compared with the experimental data obtained in the current channel of the laboratory of waves and current of COPPE/UFRJ （LOC in Portuguese acronym）. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. The presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynamic drag did not grow as fast as the lift coefficient did. The lift coefficient increased much more. Furthermore, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optimum choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat must be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average Navier-Stokes (RANS) pressure distribution,computational fluid dynamic drag

Effect of operating conditions and potassium content on Fischer-Tropsch liquid products produced by potassium-promoted iron catalysts

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Journal of Natural Gas Chemistry 2008年第2期17卷 175-178页

作者： Francisco E.m.Farias Fernando G.Sales Fabiano A.N.fernandes Universidade Federal do Ceará Departamento de Engenharia QuímicaCampus do PiciBloco 70960455-760 Fortaleza-CEBrazil

The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures （25 to 30 arm） favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure （20 arm） using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content.

关键词： Fischer-Tropsch synthesis liquid fuels iron-based catalyst potassium

Lactate Dehydrogenase Isoenzymes in mammalian Cells Exposed to Isophenphos

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Biomedical and Environmental Sciences 1995年第1期8卷 18-22页

作者： m.A.LAR.RODRIGUES m.J.B.fernandes 等 InstitutoBiologico CaixaPostal7119010641－970SaoPauloBrazil InstitutoBiologico CaixaPostal71190106

The cytotoalcity of isophenphos, an organophosphorus insecticide that has the potential to cause delayed polyneuropathy, was evaluated in GBK and V79 ce1ls. A 72 h time course following isophenphos exposure indicated a dose-dependent growth inhibition as dctermined by cell counts. The administration of isophenphos (20g/ml) to GBK cells cultured at high densities indicated a decrease in the activities of LDH isocnzymes. Analysis of V79 cells revealed a decrease of LDH3, the only LDH isocnzyme detected in these cells.

关键词： In lung LDH Lactate Dehydrogenase Isoenzymes in mammalian Cells Exposed to Isophenphos

Evaluation of bearing, gears and gearboxes performance with different wind turbine gear oils

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Friction 2015年第4期3卷 275-286页

作者： Ramiro Carneiro mARTINS Carlos m.C.G.fernandes Jorge H.O.SEABRA INEGI Universidade do PortoPortoPortugal Faculdade de Engenharia Universidade do PortoPortoPortugal

The oil viscosity specification for wind turbine gear oils is ISO VG 320,although there are quite different viscosity indexes oils for that viscosity *** work evaluates the behaviour of different base oil formulations,since polyalphaolefin(PAO),mineral,ester and polyalkeleneglycol(PAG)that withstand quite different viscosity *** oils evaluation was done in rolling bearing tests and gear *** behaviour was compared for operating conditions in the range observable in a wind turbine *** experimental results showed considerable differences between the different oils and it was observed that depending on the contact type the relative behaviour of the lubricants would change,i.e.,the best lubricant for the rolling bearing would not imply the best result on the gear *** gear geometry is also very important toward the transmission efficiency,once using a low loss gear concept a decrease of up to 25%in torque loss could be *** models were implemented with the purpose of performing a better simulation of the mechanical system and also to obtain the friction coefficient promoted by the tested oils.

关键词： gears rolling bearings friction coefficient lubricants efficiency

Effect of Noisy Fitness in Real-Time Strategy Games Player Behaviour Optimisation Using Evolutionary Algorithms

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Journal of Computer Science & Technology 2012年第5期27卷 1007-1023页

作者： Antonio m. mora Antonio Fernndez-Ares Juan J. merelo Pablo García-Snchez Carlos m. fernandes Computer Architecture and Technology Department University of Granada Institute for Systems and Robotics Technical University of Lisbon

This paper investigates the performance and the results of an evolutionary algorithm （EA） specifically designed for evolving the decision engine of a program （which, in this context, is called bot） that plays Planet Wars. This game, which was chosen for the Google Artificial Intelligence Challenge in 2010, requires the bot to deal with multiple target planets, while achieving a certain degree of adaptability in order to defeat different opponents in different scenarios. The decision engine of the bot is initially based on a set of rules that have been defined after an empirical study, and a genetic algorithm （GA） is used for tuning the set of constants, weights and probabilities that those rules include, and therefore, the general behaviour of the bot. Then, the bot is supplied with the evolved decision engine and the results obtained when competing with other bots （a bot offered by Google as a sparring partner, and a scripted bot with a pre-established behaviour） are thoroughly analysed. The evaluation of the candidate solutions is based on the result of non-deterministic battles （and environmental interactions） against other bots, whose outcome depends on random draws as well as on the opponents＇ actions. Therefore, the proposed GA is dealing with a noisy fitness function. After analysing the effects of the noisy fitness, we conclude that tackling randomness via repeated combats and reevaluations reduces this effect and makes the GA a highly valuable approach for solving this problem.

关键词： real-time strategy game genetic algorithm noisy fitness player behaviour optimisation parameter adaptation

Evaluation of Soil Quality Indicators in Sugarcane management in Sandy Loam Soil

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Pedosphere 2009年第3期19卷 312-322页

作者： S.A.C.SANT'ANNA m.F.fernandes W.m.P.m.IVO J.L.S.COSTA Brazilian Agricultural Research Corporation (Embrapa Coastal Tablelands) Av. Beira Mar 3250 Aracaju SE 49025- 040 (Brazil) Departament of Physiology Universidade Federal de Sergipe So Cristóvo SE 49100-000 (Brazil) Brazilian Agricultural Research Corporation (Embrapa Coastal Tablelands) Av. Beira Mar 3250 Aracaju SE 49025-040 (Brazil) Brazilian Agricultural Research Corporation (Embrapa) Brasília DF 70770-901 (Brazil)

An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To select soil quality indicator variables in sugarcane (Saccharum officinarum L.) production areas that fulfill the criteria of sensitivity to management practices and between-season consistency in the management discrimination, ten composite soil samples (0–10 cm) were collected in July 2005 (rainy season) and again in march 2006 (dry season) from areas under cultivation of organic sugarcane (OS), green sugarcane (GS), burned sugarcane (BS) and from an adjacent native forest (NF) area at Usina Triunfo, Boca da mata, Alagoas, Brazil. microbial biomass-C (mBC), total organic C (TOC), soil enzyme activity expressed as the rate of fluorescein diacetate (FDA) hydrolysis, mean weight diameter of water-stable soil aggregates (mWD), and percentage of water-stable macroaggregates (PWSA) were analyzed. Although mBC and TOC were higher in NF than in the cultivated areas, no differences were observed in these C pools between the three sugarcane systems. The response of FDA to the site management was dependent on the sampling time. In the rainy period, the activity followed the order: NF > OS > GS > BS, whereas in the dry season, only NF differed from the other treatments. Irrespective of the sampling time, mWD and PWSA decreased in the order NF > OS = GS > BS. The variables mWD and PWSA are quite sensitive for discriminating between site management histories regardless the sampling season.

关键词： fiuorescein diacetate green-sugarcane organic matter management sugarcane (Saccharum oJficinarum L.) sustainable agricultural use

Chromium from Hydrolyzed Leather Affects Soybean Growth and Nodulation

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Pedosphere 2019年第1期29卷 95-101页

作者： Jovana BAVARESCO Jess R.FINK moacir T.mORAES Antonio R.SNCHEZ-RODRGUEZ Ibanor ANGHINONI Department of Soils Federal University of Rio Grande do Sul Laboratory of Soil Federal Institute of Paraná Department of Agronomy University of C'ordoba

Hydrolyzed leather, obtained from industrial leather waste, is an organic nitrogenous fertilizer with a high chromium(Cr) *** crops can be adversely affected by the presence of residual Cr in soil after application of hydrolyzed leather fertilizer. The aim of this work was to assess the effect of hydrolyzed leather on Cr absorption, root development, and symbiotic nodulation of soybean plants grown on three different soils including two Lixisols and a Gleysol. These soils were previously fertilized with hydrolyzed leather at three different rates(0.0, 0.1, and 0.8 kg m^(-2)). Soybean shoot height, root development, nodulation, and mineral nutrient concentrations in plant tissues were determined after 45 d of crop growth. The application of hydrolyzed leather significantly increased Cr content in soil and Cr uptake by plants. Surprisingly, Cr was stored mainly in the aerial part of the plants. The presence of Cr had an adverse impact on shoot dry matter(41% reduction) and number of nodules(49% reduction) per plant grown on the soil with the lowest cation exchange capacity. However, no other significant effect was observed in nodule weight, diameter, or any other measured parameters.

关键词： Cr absorption Cr accumulation plant growth root development symbiotic nodulation

An Adaptive Load Stepping Algorithm for Path-Dependent Problems Based on Estimated Convergence Rates

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Computer modeling in Engineering & Sciences 2017年第3期113卷 325-342页

作者： m.T.C.Araújo fernandes C.O.Cardoso W.J.mansur Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil Petrobras/Cenpes Av.Horácio Macedo950Ilha do Fundao21941-915 Rio de JaneiroRJBrazil Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil

A new adaptive(automatic)time stepping algorithm,called RCA(Rate of Convergence Algorithm)is *** new algorithm was applied in nonlinear finite element analysis of path-dependent *** step size is adjusted by monitoring the estimated convergence rate of the nonlinear iterative *** RCA algorithm is relatively simple to implement,robust and its performance is comparable to,and in some cases better than,the automatic load incrementaion algorithm existent in commercial *** about the convergence rate of nonlinear iterative processes,an estimation of the rate and a study of the parameters of the RCA algorithm are *** show the capacity of the algorithm to adjust the increment size,detailed discussions based on results for different limit load analyses are *** results obtained by RCA algorithm are compared with those by ABAQUS?,one of the most powerful nonlinear FEA(Finite Element Analysis)commercial software,in order to verify the capability of RCA algorithm to adjust the increment size along nonlinear analyses.

关键词： Rate of convergence nonlinear automatic load incrementation limit load

Vegetation Composition and Structure of Some Neotropicamountain Grasslands in Brazil

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Journal of mountain Science 2015年第4期12卷 864-877页

作者： LE STRADIC Soizig BUISSON Elise fernandes G.Wilson Gembloux Agro-Bio Tech Université de Liège Biodiversité et paysage Passage des Déportés 2 5030 Gembloux Belgium Institut méditerranéen de Biodiversité et d’Ecologie marine et continentale (ImBE) Université d’Avignon et des Pays de Vaucluse UMR CNRS IRD Aix Marseille Université IUT site Agroparc BP 61207 F-84911 Avignon cedex 09 France Ecologia Evolutiva & Biodiversidade/Instituto de Ciências Biológicas Universidade Federal de Minas Gerais 30161-970 Belo Horizonte MG CP 486 Brazil Department of Biology Stanford University

The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be *** rupestres, some Neotropical mountain grasslands located in central Brazil and part of the Cerrado biome(covering 2 million km2) host unique plant communities, currently threatened by quarrying and *** grassy matrix of campos rupestres, has long been considered a rich mosaic under the control of local topography and the nature of substrate, but this affirmation has not been well *** analyzed whether plant communities varied in relation to edaphic factors within the stony substrate and the sandy substrate of this grassy *** selected 5 sites where occur both grasslands on stony substrate and on sandy substrate, and we carried out vegetation surveys and soil *** counted 222 plant species within our communities, among which38.6% are exclusively found on campos *** results show that both soil-types are strongly acidic, nutrient poor and exhibit a seasonal *** increases and p H and organic carbon decrease during the dry *** soils areslightly richer in nutrients than sandy soils and differences in soil granulometry and composition have led to the formation of distinct plant *** species are confined to either one or the other grassland-type, which makes the plant composition of each community *** in edaphic factors generate heterogeneous grasslands favorable to a high plant *** programs and restoration actions have to maintain or recreate this *** presence of distinct plant communities implies that different strategies might be adopted to improve the restoration of these ecosystems.

关键词： Biodiversity Campos rupestres Herbaceous community Rupestrian grassland Edaphic factor Serra do Cipó