997 resultados para timber industry


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The publication provides a snapshot of the forest and timber industry’s contribution to the Queensland economy and highlights the scope, innovation and features of the state’s forest and timber products that are produced from Queensland’s unique resources.

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Measuring the extent to which a piece of structural timber has distorted at a macroscopic scale is fundamental to assessing its viability as a structural component. From the sawmill to the construction site, as structural timber dries, distortion can render it unsuitable for its intended purposes. This rejection of unusable timber is a considerable source of waste to the timber industry and the wider construction sector. As such, ensuring accurate measurement of distortion is a key step in addressing ineffciencies within timber processing. Currently, the FRITS frame method is the established approach used to gain an understanding of timber surface profile. The method, while reliable, is dependent upon relatively few measurements taken across a limited area of the overall surface, with a great deal of interpolation required. Further, the process is unavoidably slow and cumbersome, the immobile scanning equipment limiting where and when measurements can be taken and constricting the process as a whole. This thesis seeks to introduce LiDAR scanning as a new, alternative approach to distortion feature measurement. In its infancy as a measurement technique within timber research, the practicalities of using LiDAR scanning as a measurement method are herein demonstrated, exploiting many of the advantages the technology has over current approaches. LiDAR scanning creates a much more comprehensive image of a timber surface, generating input data multiple magnitudes larger than that of the FRITS frame. Set-up and scanning time for LiDAR is also much quicker and more flexible than existing methods. With LiDAR scanning the measurement process is freed from many of the constraints of the FRITS frame and can be done in almost any environment. For this thesis, surface scans were carried out on seven Sitka spruce samples of dimensions 48.5x102x3000mm using both the FRITS frame and LiDAR scanner. The samples used presented marked levels of distortion and were relatively free from knots. A computational measurement model was created to extract feature measurements from the raw LiDAR data, enabling an assessment of each piece of timber to be carried out in accordance with existing standards. Assessment of distortion features focused primarily on the measurement of twist due to its strong prevalence in spruce and the considerable concern it generates within the construction industry. Additional measurements of surface inclination and bow were also made with each method to further establish LiDAR's credentials as a viable alternative. Overall, feature measurements as generated by the new LiDAR method compared well with those of the established FRITS method. From these investigations recommendations were made to address inadequacies within existing measurement standards, namely their reliance on generalised and interpretative descriptions of distortion. The potential for further uses of LiDAR scanning within timber researches was also discussed.

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The sustainability of current harvest practices for high-value Meliaceae can be assessed by quantifying logging intensity and projecting growth and survival by post-logging populations over anticipated intervals between harvests. From 100%-area inventories of big-leaf mahogany (Swietenia macrophylla) covering 204 ha or more at eight logged and unlogged forest sites across southern Brazilian Amazonia, we report generally higher landscape-scale densities and smaller population-level mean diameters in eastern forests compared to western forests, where most commercial stocks survive. Density of trees >= 20 cm diameter varied by two orders of magnitude and peaked at 1.17 ha(-1). Size class frequency distributions appeared unimodal at two high-density sites, but were essentially arnodal or flat elsewhere; diameter increment patterns indicate that populations were multi- or all-aged. At two high-density sites, conventional logging removed 93-95% of commercial trees (>= 45 cm diameter at the time of logging), illegally eliminated 31-47% of sub-merchantable trees, and targeted trees as small as 20 cm diameter. Projected recovery by commercial stems during 30 years after conventional logging represented 9.9-37.5% of initial densities and was highly dependent on initial logging intensity and size class frequency distributions of commercial trees. We simulated post-logging recovery over the same period at all sites according to the 2003 regulatory framework for mahogany in Brazil, which raised the minimum diameter cutting limit to 60 cm and requires retention during the first harvest of 20% of commercial-sized trees. Recovery during 30 years ranged from approximately 0 to 31% over 20% retention densities at seven of eight sites. At only one site where sub-merchantable trees dominated the population did the simulated density of harvestable stems after 30 years exceed initial commercial densities. These results indicate that 80% harvest intensity will not be sustainable over multiple cutting cycles for most populations without silvicultural interventions ensuring establishment and long-term growth of artificial regeneration to augment depleted natural stocks, including repeated tending of outplanted seedlings. Without improved harvest protocols for mahogany in Brazil as explored in this paper, future commercial supplies of this species as well as other high-value tropical timbers are endangered. Rapid changes in the timber industry and land-use in the Amazon are also significant challenges to sustainable management of mahogany. (C) 2007 Elsevier B.V. All rights reserved.

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Alternative land uses make different contributions to the conservation of biodiversity and have different implementation and management costs. Conservation planning analyses to date have generally assumed that land is either protected or unprotected, and that the unprotected portion does not contribute to conservation goals. We develop and apply a new planning approach that explicitly accounts for the contribution of a diverse range of land uses to achieving conservation goals. Using East Kalimantan (Indonesian Borneo) as a case study, we prioritize investments in alternative conservation strategies and account for the relative contribution of land uses ranging from production forest to well-managed protected areas. We employ data on the distribution of mammals and assign species-specific conservation targets to achieve equitable protection by accounting for life history characteristics and home range sizes. The relative sensitivity of each species to forest degradation determines the contribution of each land use to achieving targets. We compare the cost effectiveness of our approach to a plan that considers only the contribution of protected areas to biodiversity conservation, and to a plan that assumes that the cost of conservation is represented by only the opportunity costs of conservation to the timber industry. Our preliminary results will require further development and substantial stakeholder engagement prior to implementation; nonetheless we reveal that, by accounting for the contribution of unprotected land, we can obtain more refined estimates of the costs of conservation. Using traditional planning approaches would overestimate the cost of achieving the conservation targets by an order of magnitude. Our approach reveals not only where to invest, but which strategies to invest in, in order to effectively and efficiently conserve biodiversity.

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Bin planning (arrangements) is a key factor in the timber industry. Improper planning of the storage bins may lead to inefficient transportation of resources, which threaten the overall efficiency and thereby limit the profit margins of sawmills. To address this challenge, a simulation model has been developed. However, as numerous alternatives are available for arranging bins, simulating all possibilities will take an enormous amount of time and it is computationally infeasible. A discrete-event simulation model incorporating meta-heuristic algorithms has therefore been investigated in this study. Preliminary investigations indicate that the results achieved by GA based simulation model are promising and better than the other meta-heuristic algorithm. Further, a sensitivity analysis has been done on the GA based optimal arrangement which contributes to gaining insights and knowledge about the real system that ultimately leads to improved and enhanced efficiency in sawmill yards. It is expected that the results achieved in the work will support timber industries in making optimal decisions with respect to arrangement of storage bins in a sawmill yard.

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O processo constante de avaliação técnica e econômica dos sistemas de colheita de madeira é intrínseco às empresas florestais, devido ao fato de corresponder a uma fase de suma importância que despende elevado investimento financeiro. No experimento deste trabalho, estudaram-se o rendimento operacional e custos operacionais e de produção do processador florestal Hypro. A análise técnica englobou estudos de tempos e movimentos pelo método de tempo contínuo. O rendimento operacional foi determinado através do volume, em metros cúbicos de madeira processada. A análise econômica incorporou os parâmetros do custo operacional, custo de processamento da madeira e rendimento energético. A análise dos dados evidenciou que o rendimento operacional por hora efetiva de trabalho foi de 38 árvores e, em metros cúbicos sem casca por hora efetiva de trabalho, de 11,68 m³ h-1, com custo de processamento de madeira sem casca de US$ 6.85 por metro cúbico.

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Use of natural fibres as a reinforcement material in the manufacture of composites show a series of advantages: availability, biodegradability, low weight and regeneration in relation to synthetic fibres, thus justifying its utilization. In the present research work, composites were developed with chicken feathers (KF), using unsaturated polyester resin as matrix, for diversified applications, mainly in the furniture/timber industry.At present, in Brazil the chicken feathers are used as part of the animal feed, even though this material possesses low aggregated value. The chicken feathers are hollow, light and resistant. After washing with water at room temperature, a part of the chicken feathers were treated with 2% NaOH. Composites were manufactured using treated and untreated chicken feathers with unsaturated orthothalic polyester resin and 1% peroxide as catalyser, obtained in the commerce. Samples with size 150x25x3 mm for mechanical tests were cut by laser in the composite plate. Mechanical analyses were carried out in the Laboratório de Metais e Ensaios Mecânicos UFRN. All the analyses were in accordance with ASTM standards. SEM analyses were also carried out on the samples.In the analyses of the results obtained, it was observed that the composites made with untreated chicken feathers showed better results (Traction 11.406 MPa and 9.107 MPa Bending 34.947 and 20.918 MPa for samples with and without treatment respectively) compared to the composite with treated feathers. Very low values of the water absorption results, evidenced the impermeability characteristic of the feathers. From the SEM images, the structure, fracture and the fibre/matrix adsorption can be evidenced. In the flammability test, it was observed that despite the feathers having sulfur as a constituent, natural inhibitor of flame, no burning support of the composites, because the manufacturing process of the composite

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This study evaluated the Eucalyptus grandis drying defects acting on boards diametrical position and on log steaming. Half of the logs, with diameter from 20 to <25, 25 to <30 and 30 to <35cm, were steamed during 20 hours at 90°C of temperature. Subsequently, the logs (control and steamed) were sawn. The boards were dried in the dry-kiln pilot and the resulting defects from the drying process were measured. The results indicate that: (1) the boards coming from control logs presented different magnitude defects in function of the diametrical position. The split and spring to increase in direction to pith, the bow to increase in direction to bark and cupping were bigger in intermediary boards; (2) the boards coming from steamed logs presented a reduction from drying defects in function of logs diameter and its more homogeneous index in the pith-bark direction.

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Com o avanço do desmatamento na Amazônia brasileira, a comunidade científica internacional tem feito grande esforço na busca por formas de aproveitamento da floresta que reconciliem desenvolvimento e conservação. Desde o final da década de 1980, os pesquisadores têm explorado o papel que o extrativismo dos Produtos Florestais Não Madeireiros (PFNM) pode possuir para a economia, o bem-estar e o meio ambiente dos moradores de área de floresta. Esta dissertação explora o papel dos PFNM na vida de comunidades rurais em áreas de fronteiras da atividade madeireira ao longo do Rio Capim, no Estado do Pará. Com o avanço da indústria madeireira sobre novas fronteiras da bacia amazônica, muitas comunidades estão tendo a oportunidade de vender os direitos de exploração de sua madeira. As comunidades consideram vários aspectos para avaliar o valor dos produtos florestais. Além do valor sócio-econômico e ecológico (valor real), há um valor relativo que influencia fortemente a forma como os recursos são explorados. Este valor relativo é baseado em representações que consideram a importância dos produtos florestais e no contexto em que essas representações são construídas. Para explorar essa temática, este trabalho parte do histórico de uma comunidade cabocla enfocando na forma como ela se apropriou e explorou seus recursos florestais. Para as famílias da comunidade, a madeira sempre representou uma herança com valor de troca e uso não conflituoso. A madeira foi o produto que pôde ser gasto ao longo do tempo, pois possuía valor de mercado e suas primeiras explorações não reduziram o acesso a outros produtos florestais. Representada dessa forma, a madeira apareceu como uma possibilidade estratégica para a melhoria das condições de vida das famílias. Foram identificados quatro fatores sócio-econômicos que influenciaram a comunidade a vender a madeira: 1) relações paternalistas entre os compradores da madeira e os caboclos; 2) dificuldades de gestão comum dos recursos; 3) especialização na extração de madeira e dependência de produtos externos e; 4) crescente interesse em ter acesso a produtos provenientes do mercado. Tais fatores influenciaram a comunidade a manter a venda da madeira, mesmo depois de se tornarem evidentes as perdas no consumo de PFNM. Compreender a influência do valor atribuído pelas comunidades aos produtos florestais é fundamental para identificar a verdadeira alternativa que os PFNM podem representar diante das demais opções de uso da terra.

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Este estudo teve como objetivo avaliar o emprego do resíduo da indústria madeireira da região da Amazônia brasileira na produção de material compósito cimento-madeira. Foi avaliada a compatibilidade de seis espécies de dicotiledôneas nativas da Amazônia com o cimento CP V ARI por meio da realização de ensaios de compressão axial em corpos de prova cilíndricos. Os resíduos foram utilizados ao natural e submetidos ao tratamento de lavagem em água quente por 2 h. A relação cimento-madeira foi de 3:1, em massa, juntamente com os aditivos aceleradores de pega sulfato de alumínio a 3% e cloreto de cálcio a 3% e 5%. Os resultados dos ensaios de compressão indicaram como potencial de uso os resíduos de três espécies combinado ao tratamento com o acelerador de pega cloreto de cálcio a 5%. Foram confeccionadas chapas cimento-madeira com resíduos das espécies Cedrela Odorata L. (Cedro), Vochysia máxima Ducke (Quaruba), Hymenaea courbaril L. (Jatobá) e mais a mistura delas. Os resultados dos ensaios das propriedades físicas e mecânicas das chapas mostraram que todas apresentaram características adequadas para a finalidade, e as chapas da espécie cedro apresentaram o melhor desempenho.

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The Sanding is a complex process involving many variables that affect the quality of the part produced, working mainly in the timber industry in the production of panels (MDF, MDP, HDF, etc...) and furniture. However, these industries use the sanding process empirically, not optimizing it. The aim of this study was to compare the behavior of sandpaper white aluminum oxide (OA-white) and Black silicon carbide (SiC-black), analyzing variables in the process as: strength, power, emission, vibration, wear particle size of sanding, and its consequences on the surface finish of the workpiece. Made the process of plane grinding samples of Pinus elliottii, processed in parallel to the fibers, which were sanded with sandpaper grain OA white and black 3-SiC abrasive conditions (new, moderately eroded and severely eroded) grain sizes in 3 (80, 100, and 120 mesh). 6 replicates was performed for each condition tested. Each trial was captured output variables of the sanding process: strength, power, emission and vibration. With two stages totaling 108 trials. After the sanded samples, it has the same surface quality by raising the surface roughness Ra. Through experiment, it can be concluded that abrasives OA-white tended to have higher strength, power, emissions and less vibration in the sanding process, compared to the SiC-black. However, surface finish exhibited similar to the particle size of 80 to 100 mesh, worn abrasive conditions. However, the particle size of 120 mesh, obtained by the roughness of sandpaper OA-bank was higher compared to SiC-black to all conditions of sandpaper due to its toughness