Navegando por Autor "SANTOS, Paulo Cerqueira dos"

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Acesso aberto (Open Access)
Construction delays: a case study in the Brazilian Amazon
(Universidade Federal do Pará, 2017-09) MAUÉS, Luiz Mauricio Furtado; SANTANA, Wylliam Bessa; SANTOS, Paulo Cerqueira dos; NEVES, Renato Martins das; DUARTE, André Augusto Azevedo Montenegro
The construction industry is one of the industrial sectors with the lowest rates of fulfilment of contract deadlines, especially in developing countries. This fact has been the focus of considerable discussions seeking to identify the causes of the delays. The main purpose of this paper is to use factor analysis to identify the factors that are correlated with delay, contemplating exclusively residential real estate projects and using a city in the Brazilian Amazon as a case study. Based on the database from the government agency that authorises constructions in the city of Belém (City Planning Department - Secretaria Municipal de Urbanismo, SEURB) and data from construction companies, the study investigated 274 construction projects from the past 11 years. Factor analysis and work with the variables that can be identified and measured in the initial phase of the project, i.e., during the feasibility study, demonstrate that the physical characteristics of the apartments and the construction project are the primary causes for variations in construction delays; these causes have not yet been reported in the literature. We hope that the results of this study will contribute to more consistent forecasting of construction time, minimising the risk of delays.
Acesso aberto (Open Access)
O emprego da geoestatística na determinação do tamanho "ótimo" de amostras aleatórias com vistas à obtenção de estimativas dos volumes dos fustes de espécies florestais em Paragominas, estado do Pará
(Instituto Nacional de Pesquisas da Amazônia, 2011) SANTOS, Paulo Cerqueira dos; SANTANA, Antônio Cordeiro de; BARROS, Paulo Luiz Contente de; QUEIROZ, Joaquim Carlos Barbosa; VIEIRA, Tiago de Oliveira
The objective of this study was to determine the appropriate size sample to estimate the stem volumes stems of tree species from a population of trees to be cut in the forest management system of the timber company Cikel Brasil Verde Madeiras – Pará State, Brazil. The methodologies of systematic sampling and geostatistical kriging with sequential simulation were used, respectively, for the choice of samples and estimation of stem volumes of trees. The results showed that the methods can be used to calculate the stem volumes of trees. However, the kriging method has a smoothing effect, which resulted in an underestimation of the volumes. In such case, a correction factor was applied to minimize the effect of smoothing. The sequential simulation indicative presented more accurate results compared to kriging, since this method has certain advantages over kriging, such as not requiring samples with normal distributions and no smoothing effect characteristic of the interpolation methods.
Acesso aberto (Open Access)
Estimação volumétrica de resíduos lenhosos de madeira em uma floresta tropical através da Krigagem Ordinária, Paragominas, Estado do Pará
(2014-12) SANTOS, Paulo Cerqueira dos; SANTANA, Antônio Cordeiro de; QUEIROZ, Joaquim Carlos Barbosa; BARROS, Paulo Luiz Contente de; SANTANA, Ádamo Lima de
The objective of this paper was to test the application of geo-statistical models to estimate the volume of wood timber residues in a forest area managed in Paragominas, state of Pará. The Warren and Olsen's and Ordinary Kriging methods were used to estimate the volume of forest residues in sampled and not sampled points. The results confirm that the applied methods were appropriate, given that the estimates for the volume of wood timber residues, in the area of study, showed a small difference of 5.2%, when compared to the actual value obtained.