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Search Results: 1 - 10 of 215763 matches for " Elias de Paulo Silva "
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Avalia??o ergon?mica de modelos de cabos aéreos utilizados na extra??o florestal
Penna, Eduardo Silva;Machado, Carlos Cardoso;Souza, Amaury Paulo de;Silva, Elias;Silva, Elizabeth Neire da;
Revista árvore , 2011, DOI: 10.1590/S0100-67622011000300019
Abstract: this study was conducted in a forest company, located in the municipality of cerro azul, pr. the objective of this study was the ergonomics evaluation of using three skyline models, k301, k501 and k601 used in the extraction of full pinus spp. trees in mountainous regions. it was used a questionary answered by the operators of three existing towers, evaluating the following variables: access to cabinet work, working position of the operator, operator seat, controls and instrumentation, climate in the cabin, the cockpit visibility to the field, exhaust fumes and dust, and vibration. the models k301 and k501 models do not meet the ergonomic requirements, therefore their operators are susceptible to risks in their working hours, whereas the model k601 has satisfactory ergonomic conditions.
Uso de parcelas de areia para o monitoramento de impacto de estradas sobre a riqueza de espécies de mamíferos
Scoss, Leandro Moraes;Marco Júnior, Paulo de;Silva, Elias;Martins, Sebasti?o Venancio;
Revista árvore , 2004, DOI: 10.1590/S0100-67622004000100016
Abstract: faunal monitoring is an essential procedure to evaluate the efficiency of a conservation unit. the aims of this paper were to evaluate the use of sand-plots to record mammal tracks for estimating species richness in habitats crossed by roads and to analyze the applicability of this method to propose a monitoring program. the survey was carried out in rio doce state park, mg, in two sampling grids composed by 3 parallel transects at different distances from the forest (12, 82 and 152 m ), monitored from march to november 2000. species richness estimates were obtained by applying the estimates program and the monitor program to calculate the power of the analysis to estimate a probability of detection (p=0.90) of a decline (5%)in the number of species on the road borders. species richness estimates in the transects varied between 5.99 (sd 0.99) and 15.07 (sd 1.75). the results indicate that a monitoring program needs at least 3 surveys per year during 4 consecutive years using the same sampling protocol to detect a 5% decline in species richness on the road, with 0.90 probability. the use of sand plots is an easy-to use method that can be applied to estimate mammal species richness, and provide important information to management and conservation of these species.
Volume de enxurrada e perda de solo em estradas florestais em condi??es de chuva natural
Garcia, Alessandra Reis;Machado, Carlos Cardoso;Silva, Elias;Souza, Amaury Paulo de;Pereira, Reginaldo Sérgio;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000400014
Abstract: the total runoff volume and soil loss caused by the production of sediments derived from forest road segments under normal rainfall conditions were determined. segment slopes from 1 and 7% were analyzed, with segment lengths ranging from 20 and 40 m and width of 4 m. the road segments were marked with 0.30 m wide boards, protected with a plastic, waterproof film. rainfall volume and intensity data were daily obtained by means of pluviometers and pluviographs. data collection period was one year, concentrated in the rainy season. runoff volume was most affected by segment length while soil loss was most affected by steepness. soil sediment mass increased exponentially in function of the increased runoff volume.
Diagnóstico ambiental no contexto da paisagem de fragmentos florestais naturais "ipucas" no município de Lagoa da Confus?o, Tocantins
Martins, Iracy Coelho de Menezes;Soares, Vicente Paulo;Silva, Elias;Brites, Ricardo Seixas;
Revista árvore , 2002, DOI: 10.1590/S0100-67622002000300005
Abstract: this study was carried out at the county lagoa da confus?o, tocantins, brasil, aiming to diagnose natural forest fragments, denominated "ipucas", as well as to map different phytophysiognomic features and anthropic land uses. the basic tool used was a geographic information system (gis - idrisi 2.0 for windows). the main results achieved were: the disturbance history of the region increased after creation of the state of tocantins and the implementation of the rio formoso rice crop project; 11 cover types were identified and mapped in the area; seventy three "ipuca" natural forest fragments could be individualized and mapped, being 56% smaller than 5.00 ha and only four greater than 100.00; about 50% of these fragments have elongated shape, indicating a high perimeter/area relationship, while only three presented a circularity index close to 1.00; eight neighborhood types were identified, with five from natural environments and three resulting from anthropic effects.
Diagnóstico ambiental no contexto da paisagem de fragmentos florestais naturais "ipucas" no município de Lagoa da Confus o, Tocantins
Martins Iracy Coelho de Menezes,Soares Vicente Paulo,Silva Elias,Brites Ricardo Seixas
Revista árvore , 2002,
Abstract: Este estudo foi conduzido em uma área localizada no município de Lagoa da Confus o, Estado do Tocantins, com os objetivos de diagnosticar fragmentos florestais naturais, denominados regionalmente de "ipucas", e mapear as diferentes fei es fision micas e o uso antrópico da área. Para realiza o deste estudo utilizou-se um sistema de informa es geográficas, IDRISI 2.0. O principal resultado obtido foi o histórico de perturba o que se intensificou a partir da cria o do Estado do Tocantins e da implanta o do Projeto Rio Formoso para o cultivo de arroz irrigado; em rela o à classifica o fision mica e ao uso antrópico foram individualizadas 73 "ipucas". A partir das variáveis consideradas verificou-se que, em rela o à área, 56,16% dos fragmentos possuem áreas de até 5,00 ha e apenas quatro apresentaram áreas superiores a 100,00 ha. Aproximadamente 50% destas possuem formas alongadas, o que indica alta rela o perímetro/área. Apenas três "ipucas" apresentaram índice de circularidade (C) próximo de 1. Foram identificadas oito fei es circunvizinhas às "ipucas". Destas, cinco s o ambientes naturais (varj o-sujo, varj o-limpo, pastagem natural, corpos d'água e afloramento rochoso) e as demais resultantes de a es antrópicas (área agrícola, pastagem plantada e rede viária).
Volume de enxurrada e perda de solo em estradas florestais em condi es de chuva natural
Garcia Alessandra Reis,Machado Carlos Cardoso,Silva Elias,Souza Amaury Paulo de
Revista árvore , 2003,
Abstract: Foram determinados o volume total de água escoada e a perda de solo através da produ o de sedimentos provenientes de segmentos de estradas florestais em condi es de chuva natural, com diferentes valores de precipita es. As inclina es dos segmentos de 1 e 7% foram analisadas, enquanto os comprimentos variaram de 20 e 40 m, com 4 m de largura. Os segmentos de estrada foram delimitados com tábuas de 0,30 m de largura, envolvidas em lona plástica, para sua impermeabiliza o. Os dados de volume e intensidade de precipita o diária foram obtidos com a instala o de pluvi metro e pluviógrafo no local. O período de coleta de dados foi de um ano, concentrando-se na época das chuvas. O volume de enxurrada foi mais afetado pelo comprimento do segmento, ao passo que a massa de solo sofreu maior influência da declividade. A massa de solo erosinado cresceu exponencialmente em fun o do incremento do volume de enxurrada.
Advanced ceramics: evaluation of the mechanism of stock removal and ground surface quality
Bianchi Eduardo Carlos,Silva Eraldo Jannone da,Silva Júnior Carlos Elias da,Aguiar Paulo Roberto de
Journal of the Brazilian Society of Mechanical Sciences , 2001,
Abstract: The aim of this work is to evaluate the mechanism of stock removal and the ground surface quality of advanced ceramics machined by a surface grinding process using diamond grinding wheels. The analysis of the grinding performance was done regarding the cutting surface wear behavior of the grinding wheel for ceramic workpieces. The ground surface was evaluated using Scanning Electron Microscopy (SEM). As a result it can be said that the mechanism of material removal in the grinding of ceramic is largely one of brittle fracture. The increase of the h max can reduce the tangential force required by the process. Although, it results in an increase in the surface damage, reducing the mechanical properties of the ground component.
Rela??es solo-geoambiente em áreas de ocorrências de Ipucas na planície do Médio Araguaia - Estado de Tocantins
Martins, Alan Kardec Elias;Schaefer, Carlos Ernesto G. R.;Silva, Elias;Soares, Vicente Paulo;Corrêa, Guilherme Resende;Mendon?a, Bruno Araújo Furtado de;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000200017
Abstract: amongst the landscape features of mid araguaia river valley, there are vast coalesced floodplains and waterlogging depressions, all seasonally inundated. there, scattered forest fragments are found, being regionally called 'ipucas', with peculiar floristic and geomorphic features. these forest fragments are elements of the natural transition zone (ecotone) between amazonia forest and cerrado. we selected an area of approximately 8.200 ha in the municipality of 'lagoa da confus?o', for detailed studies of nine soil profiles. all pedoenvironments were characterized, with emphasis on the ipucas and their ecological relationships. there is a dominance of nutrient-depleted soils, most with gleying and plinthite, with varying amounts of organic carbon. except for the eutrophic haplic cambisols on calcareous substrate from the elevated border, all soils from the floodplain (dystrophic plinthosols and gleysols) are acid and nutrient-poor, even under 'ipucas' forest formation. in the ipucas, organic matter accumulates due to acid-reducing condition, being extremely fragile to human intervention. for this reason, and considering the low degree of connection between forest fragments, ipucas should be considered as permanent protected areas, being closely related to the overall hydrological cycle of the araguaia floodplain.
Níveis de proteína e fósforo em ra??es com fitase para frangos de corte, na fase de 14 a 21 dias de idade: 2. valores energéticos e digestibilidade de nutrientes
Silva, Yolanda Lopes da;Rodrigues, Paulo Borges;Freitas, Rilke Tadeu Fonseca de;Zangeronimo, Márcio Gilberto;Fialho, Elias Tadeu;
Revista Brasileira de Zootecnia , 2008, DOI: 10.1590/S1516-35982008000300012
Abstract: a digestibility assay was carried out to determine the apparent metabolizable energy values (amen), dry matter digestibility coefficients (dmdc), the excretion and apparent retention coefficient of phosphorus (p), nitrogen (n), calcium (ca), potassium (k), copper (cu) and zinc (zn), using 250 cobb male broiler chickens receiving the treatments distributed in a factorial schedule 3 ′ 3 + 1 (available phosphorus level - 0.25; 0.34 and 0.45% and crude protein level [cp]- 15.0; 17.0 and 19.0% and a control diet, with normal nutritional levels), with five replicates of five birds each. in the diets with reduced levels of available phosphorus (ap), 500 ftu of phytase were added and calcium requirement was reduced in 17%. except for control treatment, all the diets were formulated on digestible amino acids basis. the energetic values of the diets with 15.0 and 17.0% cp, independently of the ap levels used or the phytase supplementation, presented higher amen that the control diet possibility regarding to supplemental amino acids addition. the dmdc of the diets with reduced cp levels and different levels of ap were higher than the control diet. the cp reduction in the diet associated to lower ap levels and phytase enzyme supplementation allowed to reduce the minerals excretion, which showed better retention coefficients, except for zinc that presented lower retention coefficient than the the control diet. however, all minerals excretion, as relatively compared to the control diet, was minimized when lower levels of cp and ap was used in the diet, supplemented with phytase. the manipulation of the protein and phosphorus levels in diets supplemented with amino acids and phytase could reduce mainly the excretion of nitrogen, p and cu, minimizing the environment pollution caused by these elements.
Application of the Minimum Quantity Lubrication (MQL) technique in the plunge cylindrical grinding operation
Alves, José Augusto Camargo;Fernandes, Ulysses de Barros;Silva Júnior, Carlos Elias da;Bianchi, Eduardo Carlos;Aguiar, Paulo Roberto de;Silva, Eraldo Jannone da;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2009, DOI: 10.1590/S1678-58782009000100001
Abstract: precision cylindrical grinding is used extensively in the manufacture of precision components in the metal-mechanical industry in general. modern cnc grinding machines have improved this process with respect to the positioning and rigidity of the machine-workpiece-tool system, allowing the production of high precision parts with low dimensional tolerances. besides the difficulties inherent to the process, awareness has grown in recent years regarding the environmental issues of cutting fluids. as a response, the industry has begun to seek alternative lubrication and cooling methods. among the various existing techniques, minimum quantity lubrication (mql) has been considered as an alternative. this technique can be understood as a combination of conventional lubrication and cooling methods and dry machining, in which a small quantity of lubricating oil mixed with compressed air flow is delivered in the wheel-workpiece interface. the mql technique is already widely employed in machining processes with tools of defined geometry (e.g. turning), in which produces very satisfactory results. however, the mql technique has been little explored in grinding processes (non-defined tool geometry), in which the really effective heat removal methods are required due to the frictional heat generation in the grinding zone. consequently, the aim of this study was to evaluate the plunge cylindrical internal grinding operation when using the mql technique and the conventional cooling method. roughness and roundness were the outputparameters. as a result, it was found that the best values of roughness ra were obtained with the conventional lubrication method. the mql technique applied as proposed was not able to flush the chips away from the grinding zone, leading to the highest ra values. no significant differences were detected among the cooling methods when analyzing the roundness results. the workpiece fixture method selected was responsible for the overall unsatisfactory results.
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