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Search Results: 1 - 10 of 15094 matches for " Samuel Soares; "
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Seguran a e defesa no Cone Sul: transi es com transforma es?
Soares, Samuel Alves
Estudos Ibero Americanos , 2008,
Abstract: As novas condicionantes da seguran a internacional, em que n o somente as soberanias e rela es inter-estatais possuem peso significativo, têm ensejado mudan as nas possibilidades e exigências para as políticas de defesa. Países do Cone Sul procuram estabelecer novos parametros na defini o de suas políticas, mas se encontram tensionados entre estabelecer políticas dissuasórias, como no passado, ou instituir mecanismos de coopera o com seus vizinhos. Por outro lado, etas políticas, pela sua natureza e amplitude, inserem-se sobre temas que n o s o exclusivamente militares. O objetivo do artigo é analisar as condicionantes estratégicas e defini es estatais acerca da dissuas o e da coopera o em seguran a internacional, e identificar o grau de autonomia e a natureza das concep es originadas das for as armadas na defini o das políticas de defesa. Enfim, trata-se de verificar o grau de dire o política do poder civil nas defini es das políticas de defesa. The new conditions of international security don’t only attach importance to sovereignty and interstate relations. This new framework has led to changes in the scope and requirements for Politics of Defense. Countries of the Southern Cone seek to establish new parameters in the definition of their policies, but need to define between dissuasive policies, as in the past, or establish mechanisms for cooperation with their neighbors. Furthermore, these policies, by their nature and size, are not exclusively militaries. The purpose of this article is to examine the definitions constraints on strategic deterrence and cooperation in international security, and identify the degree of autonomy and the nature of the concepts derived from the armed forces in shaping Politics of Defense. Finally, we try to check the level of civil policy direction in defining those policies.
Florística e estrutura de comunidades arbóreas em cerrados de Rond?nia,Brasil
Miranda, Izildinha Souza;Almeida, Samuel Soares;Dantas, Paulo Jorge;
Acta Amazonica , 2006, DOI: 10.1590/S0044-59672006000400004
Abstract: the neotropical savannas, locally called "cerrado", are brazil's second largest and diverse biome, constituting a heterogeneous physiognomic and floristic mosaic from which more than 6,000 species have been reported to date. this study describes and analyzes the floras and structures of four tree communities from dry savannas in the municipality of vilhena, rond?nia, brazil. the study areas were: savanna with trees "cerrad?o" (area 1), savannas wich bushes or "campo sujo" (area 2), and two savanna woodlands or "cerrado" sensu stricto (areas 3 and 4). in each area an transect measuring 10 x 1,000 m (1 ha) was placed at random and divided into 100 quadrats of 10 x 10 m. all living and dead woody plants with circumference 3 10 cm at ground level were included in the survey. "cerrad?o" was the richest in species, had the greatest plant diversity, and showed the largest basal area. the percentages of dead trees were highest in areas that had been recently burned. the most species-rich and abundant plant families were vochysiaceae, ochnaceae, guttiferae, malpighiaceae and melastomataceae. the most important species were qualea multiflora and byrsonima crassifolia (area 1), eugenia sp. and miconia sp.1. (area 2), ouratea hexasperma and caraipa savannarum (area 3) ouratea hexasperma and pouteria sp3. (area 4). most species (53%; n=92 spp.) were found in only one of the four areas, indicating that the selection of priority areas for biological conservation should take into account the whole of the savanna mosaic. tree mortality caused by fire was different among the four study areas, probably as a function of burning recurrency, the degree of flammability, and historical factors involving land use.
LóGICA FUZZY NO MAPEAMENTO DE VARIáVEIS INDICADORAS DE FERTILIDADE DO SOLO
Assis Silva,Samuel de; Soares de Souza Lima,Juli?o;
Idesia (Arica) , 2009, DOI: 10.4067/S0718-34292009000300007
Abstract: the objective of his experiment was to use fuzzy logic to map the sum of bases (sb), cation exchange capacity (ctc) and base saturation (v%) in an area with arabica coffee variety catucai, considering the spatial variability . the samples of soil were held in a loop with 50 sampling points in the projection of the crown of the plants. the data were subjected to a descriptive analysis and exploratory. we used a classification system in the integration of fuzzy values of attributes. then preceded a geistatistic analysis to quantify the degree of dependence of the possibilities of spatial attributes. based on the attributes evaluated, the area has low possibility of development and yield of crops, since these attributes showed a low possibility of availability.
Multivariate analysis and geostatistics of the fertility of a humic rhodic hapludox under coffee cultivation
Silva, Samuel de Assis;Lima, Juli?o Soares de Souza;
Revista Brasileira de Ciência do Solo , 2012, DOI: 10.1590/S0100-06832012000200016
Abstract: the spatial variability of soil and plant properties exerts great influence on the yeld of agricultural crops. this study analyzed the spatial variability of the fertility of a humic rhodic hapludox with arabic coffee, using principal component analysis, cluster analysis and geostatistics in combination. the experiment was carried out in an area under coffea arabica l., variety catucai 20/15 - 479. the soil was sampled at a depth 0.20 m, at 50 points of a sampling grid. the following chemical properties were determined: p, k+, ca2+, mg2+, na+, s, al3+, ph, h + al, sb, t, t, v, m, om, na saturation index (ssi), remaining phosphorus (p-rem), and micronutrients (zn, fe, mn, cu and b). the data were analyzed with descriptive statistics, followed by principal component and cluster analyses. geostatistics were used to check and quantify the degree of spatial dependence of properties, represented by principal components. the principal component analysis allowed a dimensional reduction of the problem, providing interpretable components, with little information loss. despite the characteristic information loss of principal component analysis, the combination of this technique with geostatistical analysis was efficient for the quantification and determination of the structure of spatial dependence of soil fertility. in general, the availability of soil mineral nutrients was low and the levels of acidity and exchangeable al were high.
Número de postos pluviométricos necessários para a estimativa da precipita??o mensal no estado do Espírito Santo, Brasil
Silva, Samuel de Assis;Lima, Juli?o Soares de Souza;
Revista Brasileira de Meteorologia , 2011, DOI: 10.1590/S0102-77862011000400005
Abstract: the objectives proposed in this study were to determine the spatial distribution of monthly average rainfall in the state, using the altitude of the rain gauge stations as co-variable and determining the number of points necessary to map the precipitation, considering the spatial dependence. the used data in this study include precipitation series ranging from 33 to 72 years, totaling 55 rain gauge stations. the data series were subjected to descriptive analysis and geostatistics. the co-kriging using the altitude as the covariateble showed considerable accuracy in the estimation of precipitation. the kriging cross variogram showed that 37 rain gauges are enough to characterize the monthly precipitation with spatial dependence over the state.
Avalia??o da variabilidade do estado nutricional e produtividade de café por meio da análise de componentes principais e geoestatística
Silva, Samuel de Assis;Lima, Juli?o Soares de Souza;
Revista Ceres , 2012, DOI: 10.1590/S0034-737X2012000200017
Abstract: evaluation of plant nutritional status brings several contributions to the coffee crop, especially when considering the spatial variation in the production fields. this experiment aimed to analyze the spatial variability in the nutritional status and yield of arabic coffee, using the principal component analysis (pca) and geostatistics. the experiment was conducted in a grid of 50 sampling points in a field of coffea arabica l., cv. catuaí. leaf samples were taken for macro and micronutrient analyses, and fruit were collected for yield evaluation. data were subjected to pca for transformation of nutrient values into new variables and then submitted to geostatistics to quantify the degree of spatial dependence of the main components and yield. the combined use of pca and geostatistics allowed the efficient study of the nutritional status of the plants. the crop showed nutritional imbalance, with excess n and cu limiting yield even in areas with adequate leaf concentration of the other nutrients.
Integrando o custeio baseado em atividades com a Teoria das Restri es: a aplica o do ABC operacional em uma odontoclínica.
Anderson Soares Silva,Luiz Claudio Otranto Alves,Samuel Cogan
Revista de Administra??o Mackenzie , 2007,
Abstract: O custeio baseado em atividades (ABC) tem sido criticado por sua incapacidade de dar suporte às decis es de produ o baseadas no curto prazo, sendo, por isso, considerado uma sistemática de aloca o de custos para o longo prazo. Robert Kee, no artigo “Evaluating the economics of short-and long-run production decisions”, desenvolve um modelo de ABC, denominado operacional, que incorpora custos flexíveis de recursos de atividades e restri o de capacidade para decis es de mix ótimo de produ o no curto prazo. Ao apresentar um exemplo numérico hipotético, Kee mostra que seu modelo de ABC operacional apresenta, no curto prazo, resultados superiores ao modelo de ABC tradicional e a outro modelo de ABC que leva em conta t o-somente a restri o de capacidade. O presente artigo analisa o modelo proposto por Kee (2001) mediante sua aplica o em uma odontoclínica da administra o pública federal, comparando os resultados obtidos pela referida sistemática com os encontrados pelo ABC tradicional e pela teoria das restri es (TOC), aplicados à mesma organiza o, concluindo pela superioridade do modelo de Kee.
LóGICA FUZZY NO MAPEAMENTO DE VARIáVEIS INDICADORAS DE FERTILIDADE DO SOLO FUZZY LOGIC TO MAP OF VARIABLES INDICATIVE OF SOIL FERTILITY
Samuel de Assis Silva,Juli?o Soares de Souza Lima
IDESIA , 2009,
Abstract: O objetivo desse experimento foi utilizar a lógica fuzzy no mapeamento da soma de bases (SB), capacidade de troca de cátions (CTC) e da satura o por bases (V%) em urna área cultivada com café arábica variedade catucaí, considerando a variabilidade espacial. As coletas de solo foram realizadas em urna malha com 50 pontos amostráis na proje o da copa das plantas. Os dados foram submetidos a urna análise descritiva e exploratoria. Utilizou-se um sistema de classifica o fuzzy na integra o dos valores dos atributos. Em seguida procedeu-se a análise geoestatística, para quantificar o grau de dependência espacial das possibilidades dos atributos. Com base nos atributos avaliados, a área apresenta baixa possibilidade de desenvolvimento e rendimento da cultura, urna vez que esses atributos apresentaram baixa possibilidade de disponibilidade. The objective of his experiment was to use fuzzy logic to map the sum of bases (SB), cation exchange capacity (CTC) and base saturation (V%) in an area with Arabica coffee variety Catucai, considering the spatial variability . The samples of soil were held in a loop with 50 sampling points in the projection of the crown of the plants. The data were subjected to a descriptive analysis and exploratory. We used a classification system in the integration of fuzzy values of attributes. Then preceded a geistatistic analysis to quantify the degree of dependence of the possibilities of spatial attributes. Based on the attributes evaluated, the area has low possibility of development and yield of crops, since these attributes showed a low possibility of availability.
Market Opportunity of Some Aluminium Silicon Alloys Materials through Changing the Casting Process
George CHIRITA,Mioara CHIRITA,Delfim SOARES,Samuel SILVA
Annals of Dun?rea de Jos University. Fascicle I : Economics and Applied Informatics , 2012,
Abstract: Fatigue is considered to be the most common mechanism by which engineering components fail, and it accounts for at least 90% of all service failures attributed to mechanical causes. Mechanical properties (tensile strength, tensile strain, Young modulus, etc) as well as fatigue properties (fatigue life) are very dependent on casting method. The most direct effects of casting techniques are on the metallurgical microstructure that bounds the mechanical properties. One of the important variables affected by the casting technique is the cooling rate which is well known to strongly restrict the microstructure. In the present research has been done a comparison of fatigue properties of two aluminum silicon alloys obtained by two casting techniques. It was observed that the fatigue life is increasing with 24% for Al12Si and 31% for AL18Si by using centrifugal casting process instead of gravity casting. This increasing in fatigue life means that a component tailored from materials obtained by centrifugal casting will stay longer in service. It was made an estimation of the time required to recover the costs of technology in order to use the centrifuge process that will allow to obtain materials with improved properties. The amortization can be achieved by using two different marketing techniques: through the release of the product at the old price and with much longer life of the component which means "same price - longer life", or increasing price, by highlighting new product performance which means "higher price - higher properties".
Effect of trace elements on the interface reactions between two lead-free solders and copper or nickel substrates
Soares D.,Vilarinho C.,Barbosa J.,Samuel F.
Journal of Mining and Metallurgy, Section B : Metallurgy , 2007, DOI: 10.2298/jmmb0702131s
Abstract: Traditional Sn-Pb solder alloys are being replaced, because of environmental and health concerns about lead toxicity. Among some alternative alloy systems, the Sn-Zn and Sn-Cu base alloy systems have been studied and reveal promising properties. The reliability of a solder joint is affected by the solder/substrate interaction and the nature of the layers formed at the interface. The solder/substrate reactions, for Sn-Zn and Sn-Cu base solder alloys, were evaluated in what concerns the morphology and chemical composition of the interface layers. The effect of the addition of P, at low levels, on the chemical composition of the layers present at the interface was studied. The phases formed at the interface between the Cu or Ni substrate and a molten lead-free solder at 250oC, were studied for different stage times and alloy compositions. The melting temperatures, of the studied alloys, were determined by Differential Scanning Calorimetry (DSC). Identification of equilibrium phases formed at the interface layer, and the evaluation of their chemical composition were performed by Scanning Electron Microscopy (SEM/EDS). Different interface characteristics were obtained, namely for the alloys containing Zn. The obtained IML layer thickness was compared, for both types of alloy systems.
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