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Parametros dendrométricos e correla？？es com propriedades tecnológicas em um híbrido clonal de Eucalyptus urophylla x Eucalyptus grandis
Gon？alves, Fabricio Gomes;Oliveira, José Tarcísio da Silva;Silva, Gilson Fernandes da;Nappo, Mauro Eloi;Tomazelo Filho, Mario;
Revista árvore , 2010, DOI: 10.1590/S0100-67622010000500020
Abstract: wood quality is apparently associated with the dendrometric characteristics that are influenced by growth conditions. the aim of this study was the dendrometric characterization and realization of pearson correlations among some technological parameters in the clonal hybrid wood eucalyptus urophylla x eucalyptus grandis grown in three silvicultural extracts. the dendrometric data were analyzed by regression analysis. the results show that the hybrid presents similar behavior to other eucalypt of the same species grown in other places with sapwood thickness in e1 (coppice with 70 months and one thinning), with little variation along the stem. all evaluated trees presented, in general, a low taper along the stem with very little bark volume among the extracts. the pearson correlation studied nine dendrometric parameters, seven physical and three mechanical properties. the parameters were evaluated, longitudinally, in three meter sections along the stem and in the pith-bark position in the first two logs according to the pearson's correlation. the coefficients demonstrated a strong correlation among the properties, with basic density being highly correlated to the other characteristics and anisotropic coefficient, important in the process of sawing and drying wood, as well as sapwood thickness. the correlation to the height relationship wasn't significant to the linear and volumetric shrinkage. radial variation showed a good correlation among all the evaluated mechanical properties in the two first logs. on the other hand, the physical properties in the radial position didn't present significant correlations with tangential shrinkage.
Evaluation of taper functions aiming Eucalyptus sp stem optimizatio for multi-products
Adriano Ribeiro de Mendon？a,Gilson Fernandes da Silva,José Tarcísio da Silva Oliveira,Gilciano Saraiva Nogueira
CERNE , 2007,
Abstract: This work evaluate different models for estimating volume and height along the stem, in order to guarantee more precise inputs in the optimization systems for obtaining multi-products. It was tested the taper equations proposed by Demaerschalk, Ormerod, Schoepfer and Hradelzky. These models were tested for the commercial diameter of 7 and 28 cm in Eucalyptus sp. trees. The database was obtained from upper stem diameter measurements of 16 years-old trees, in a total of 32 sample trees for the model fitting and 27 sample trees for the validation test. Based on the graphic residual analysis, on the statistics (correlation coefficient, relative standard error, “bias” (B), average of the differences (MD) and standard deviation of the differences (DPD) and on the test of Leite & Oliveira (2002), it was verified that the Ormerod model presented better volume estimates and the Schoepfer model provided better height results.
Influencia de diferentes fontes de erro sobre as medi？？es de alturas de árvores
Silva, Gilson Fernandes da;Oliveira, Onair Mendes de;Souza, Carlos Alberto Martinelli de;Soares, Carlos Pedro Boechat;Lemos, Ronielly;
CERNE , 2012, DOI: 10.1590/S0104-77602012000300006
Abstract: the objective of this study was to evaluate the influence of different sources of variation in tree height measurements using hypsometers based on trigonometric principles. the use of this type of device requires that the measurement is at a known distance from the tree. therefore, if these distances are small or too big, oscillations can occur during the reading of the device or difficulties to visualize the tree tops, causing errors in the height measurement. thereby, in this study a set of tree heights were measured with a hypsometer at different distances and by three different individuals. afterwards, the results were compared with the actual heights of the trees obtained by climbing them. finally, after the analysis, the results indicated that the distance of measurement, along with the hypsometer used, affects in obtaining estimation of the total height.
Influence of different sources of errors on the measurements of heights of trees
Gilson Fernandes da Silva,Onair Mendes de Oliveira,Carlos Alberto Martinelli de Souza,Carlos Pedro Boechat Soares
CERNE , 2012,
Abstract: The objective of this study was to evaluate the influence of different sources of variation in tree height measurements using hypsometers based on trigonometric principles. The use of this type of device requires that the measurement is at a known distance from the tree. Therefore, if these distances are small or too big, oscillations can occur during the reading of the device or difficulties to visualize the tree tops, causing errors in the height measurement. Thereby, in this study a set of tree heights were measured with a hypsometer at different distances and by three different individuals. Afterwards, the results were compared with the actual heights of the trees obtained by climbing them. Finally, after the analysis, the results indicated that the distance of measurement, along with the hypsometer used, affects in obtaining estimation of the total height.
Characterization socio-demographic of patients with venous ulcers treated at a university hospital
Eurides Araújo Bezerra de Macêdo, Aminna Kelly Almeida de Oliveira, Gabriela de Sousa Martins Melo, Walkíria Gomes da Nóbrega, Isabelle Katherinne Fernandes Costa, Daniele Vieira Dantas, Felismina Rosa Parreira Mendes, Gilson de Vasconcelos Torres
Revista de Enfermagem UFPE On Line , 2010,
Abstract: Objective: Characterize sociodemographic patients with venous ulcers (UV) participating in a study developed at University Hospital, Natal / RN. Methodology: This is an analytical type of therapeutic intervention intra-group is not randomized 18 patients performed with UV outpatient clinic of Angiology of a university hospital in Natal / RN. Was approved by the Ethics and Research / CEP HUOL UFRN (no 276/09). The data collection was performed in four months, through a survey instrument consisting of a structured interview applied in the patient's admission to the study and an observation script checks implemented in the ten checks subsequent admission. The data were categorized in Microsoft Excel and processed using the SPSS 15.0 by descriptive statistics. Results: identified himself a predominance among patients with UV female (88.9%), equality in the two age ranges, mostly with low education (83.3%) and low family income (77.8%), with any profession (94,4%), and for the current occupation most patients were retired or unemployed (55.6%). Conclusion: it was noticed a trend of emergence of UV, in females, with socio-economic conditions unfavorable and with low education
Convexity Analysis of Snake Models Based on Hamiltonian Formulation
Gilson Antonio Giraldi,Antonio Alberto Fernandes de Oliveira
Computer Science , 2005,
Abstract: This paper presents a convexity analysis for the dynamic snake model based on the Potential Energy functional and the Hamiltonian formulation of the classical mechanics. First we see the snake model as a dynamical system whose singular points are the borders we seek. Next we show that a necessary condition for a singular point to be an attractor is that the energy functional is strictly convex in a neighborhood of it, that means, if the singular point is a local minimum of the potential energy. As a consequence of this analysis, a local expression relating the dynamic parameters and the rate of convergence arises. Such results link the convexity analysis of the potential energy and the dynamic snake model and point forward to the necessity of a physical quantity whose convexity analysis is related to the dynamic and which incorporate the velocity space. Such a quantity is exactly the (conservative) Hamiltonian of the system.
Uma proposta para a gera？？o de amostras aleatórias nos problemas de simula？？o em modelos de planejamento
Peternelli, Luiz Alexandre;Silva, Gilson Fernandes da;Leite, Helio Garcia;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000500008
Abstract: a cellulose price prediction model was adjusted using time and lagged price as covariates. from the model parameter estimates, 48 possible trends were proposed for future cellulose price. following, three simulation methods were used to predict the future values defined by the various trends: m1t pcel.f = μ; m2 t pcel.f = μ + ef, e m3 μf + ef, where m is the systematic part and ef is the stochastic component. the monte carlo method and a triangular distribution were used for the simulation. to compare the values simulated by the methods and the future values of the various trends, the average relative difference was used. in case of no trend, m1 and m2 were satisfactory, although m2 included disturbances around the mean. in the case of a real trend, m3 had the best performance, though it was influenced by the accuracy in the predicted trend.
Análise fitossociológica da Floresta Nacional de Pacotuba, Cachoeiro de Itapemirim, ES - Brasil
Abreu, Karla Maria Pedra de;Silva, Gilson Fernandes da;Silva, Aderbal Gomes da;
CERNE , 2013, DOI: 10.1590/S0104-77602013000100019
Abstract: this study evaluated the structure of the tree community of pacotuba national forest, in cachoeiro de itapemirim - es. for the phytossociological inventory, 12 sample plots of 40 x 50 m each were systematically laid out. all trees with dbh≥5 cm were measured and identified. the phytossociological analysis was based on the absolute and relative parameters of density, dominance, frequency, importance values and basal area values. the diametric structure was analyzed using diameter class histograms defined by spiegel's formula a total of 3570 individuals, 253 species and 52 families were sampled. the species with the highest importance value (iv) were: senefeldera verticillata, actinostemon estrellensis, anadenanthera peregrina. the diametric curves (j-reverse shape) and values of liocourt' s 'q' quotient suggested problems involving lack of regeneration. the value of basal area (25,72 m2.ha-1) and the highest dominance of few species classified this fragment as in the intermediate stage of succession. however, due to the expressive species richness and the presence of some endangered tree, this remnant forest should be considered as a priority area for establishment of conservation and management practices.
Problemas com o uso de programa o linear com posterior arredondamento da solu o ótima, em regula o florestal
Silva Gilson Fernandes da,Leite Helio Garcia,Silva Márcio Lopes da,Rodrigues Flávio Lopes
Revista árvore , 2003,
Abstract: O principal objetivo deste trabalho foi avaliar, com a ajuda da Programa o Inteira, as conseqüências do uso da Programa o Linear com posterior arredondamento das respostas, com ênfase na regula o de florestas eqüianeas. Para isto, um problema de regula o florestal simplificado foi idealizado e resolvido pelo modelo I, por meio de Programa o Linear, Programa o Linear com posterior arredondamento e Programa o Inteira. Ao final, concluiu-se que o arredondamento das respostas obtidas pelo modelo resolvido por Programa o Linear levou a uma solu o inviável para o problema de regula o proposto. O mesmo n o ocorreu com o modelo de Programa o Inteira, que apresentou um plano de regula o factível e otimizado, mostrando que, do ponto de vista matemático, respostas com arredondamento da solu o de modelos de Programa o Linear n o devem ser adotadas.
INFLUêNCIA DE ESTIMATIVAS DE PRODU O DE MADEIRA EM PROCESSOS DE REGULA O FLORESTAL UTILIZANDO PROGRAMA O LINEAR
Gilson Fernandes da Silva,Helio Garcia Leite,Carlos Pedro Boechat Soares,Márcio Lopes da Silva
Ciência Florestal , 2002,
Abstract: Este trabalho teve como principal objetivo avaliar as conseqüências do uso de estimativas de produ o oriundas de diferentes modelos de crescimento e produ o em um modelo de Programa o Linear aplicado à regula o florestal. Assim, utilizando dados de um inventário florestal contínuo, obtiveram-se diferentes estimativas da produ o futura em volume, pelo ajuste de um modelo de produ o em fun o da idade, outro em fun o da idade e do índice de local e por um terceiro modelo que incluiu, além da idade e do índice de local, a densidade, representada pela área basal por hectare. Testou-se também um modelo baseado nos dados de inventário florestal contínuo que utiliza os dados de volume de um período para fazer proje es lineares da produ o para o período seguinte. Em seguida, um problema de regula o florestal simplificado foi idealizado e resolvido pelo modelo I por meio de Programa o Linear, utilizando dados oriundos dos quatro modelos de predi o do volume. Ao final, concluiu-se: a) que modelos de regula o florestal, alimentados por estimativas provenientes de diferentes modelos de produ o, quando resolvidos por Programa o Linear, resultam em diferentes maneiras de se conduzir a floresta; b) que a matriz de coeficientes tecnológicos, alimentada por diferentes dados de produ o e para uma mesma fun o objetivo, afeta, de maneira significativa, o processo de tomada de decis o.
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