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A structural model with interventions for new Zealand sawn timber production  [PDF]
Dongwen Luo,Geoffrey Jones,Judith Dennis
Advances in Decision Sciences , 2006, DOI: 10.1155/jamds/2006/12619
Abstract: Timber production in New Zealand was privatized in 1987. We examine the effects of this change on the level of New Zealand sawn timber production, and changes in the seasonal pattern, using a state-space model with intervention variables. We describe the formulation and estimation of the state-space model, and show how it can be used to examine both the structural changes around the time of privatization and the gradually evolving seasonal pattern in production. We also show how the model can be used to forecast future production.
Quality of Pinus elliottii sawn timber from tapped forests  [PDF]
Pedro Henrique Gonzalez de Cademartori,Darci Alberto Gatto,Diego Martins Stangerlin,Eduardo Schneid
CERNE , 2012,
Abstract: This study aimed to characterize the quality of Pinus elliottii sawn timber extracted from tapped forests and processed in a sawmill in S o José do Norte (RS). Four butt logs and four upper logs for each of the three existing diameter grades were selected and sawed. The wood pieces were analyzed after sawing and after kiln drying. The presence of knots, which occurred due to the absence of forest management and influenced the qualitative classification of the wood pieces, was observed mainly in the samples from upper logs. The process of resin tapping contributed to a higher incidence of resin pockets in the samples from butt logs, also influencing the qualitative classification of the samples. The appearance of drying defects did not modify the classification of the wood samples from butt and upper logs.
INFLUENCE OF TANGENTIAL BREAK DOWN METHODS ON THE YIELD AND ON THE QUALITY OF Eucalyptus spp SAWN TIMBER
Sérgio Ferreira,José Tarcísio Lima,Sebasti?o Carlos da Silva Rosado,Paulo Fernando Trugilho
CERNE , 2004,
Abstract: This work evaluated the production and the quality of green sawn timber of ten clones of Eucalyptus hybrids. The logs were classified according to their defects and were sawn in a band saw, using three variations of the balanced tangential method: parallel to the centre of the log (M1), cutting slabs at 1/3 of the log ray (M2) and parallel to the bark (M3). Following the logs breakdown, the yield was calculated and the sawn timber was sorted in terms of warp and splits. All clones presented logs with small taper, low bowing and high circularity; the smaller end splits of the logs were presented by clones 280, 36 and 299; clones 62, 2 58 and 36 presented the smallest pith eccentricity. The average lumber recovery between clones, obtained in the three breakdown methods were 35.2 % for the method M1; 30.1 % for the method M2 and 37.2 % for the method M3. These figures were increased when the production of the central plank and rips, removed from the slabs were considered in the account. Clones 44a, 62 and 36 presented highest lumber recovery. Bowing was small in all clones (average = 3.0 mm/m) presenting small variation among the three tested breakdown methods; similar behaviour was observed for lumber crook (average = 0.93 mm/m); the clone 44a presented the smallest lumber checks in the three tested breakdown methods (average = 5.7 %). Cluster Analysis, indicated to verify that clones 44a and 62 presented best sawn timber recovery and check performance.
Mechanical characterization of sawn timber for structural use, graded visually in accordance with Spanish standard UNE 56544
Fernández-Golfín, J. I.,Díez Barra, M. R.,Gutiérrez Oliva, A.
Materiales de Construccion , 1998,
Abstract: The employment of timber in structures in Spain was hurting of the nonexistence of accepted calculation procedures. The recent adoption and publication of the Eurocode 5 compels to the employment of the characteristic values of the material in the structural calculation by the method of the finite elements. This report sets forth the results of the experiments carried out at INIA's Forest Research Centre (CIFOR-INIA) regarding the mechanical characterization of sawn timber of size 150x50x3.000 mm and the structural uses of "Pinus sylvestris, P. radiata and P. pinaster" from different Spanish provenances. The characteristic values and strength classes corresponding with the grades stated in the Spanish standard UNE 56544 are also provided. The report compares and analyses the results of these experiments, and presents the conclusions drawn from the different behaviour shown by the four species. An analysis of the Spanish standard for the visual grading of structural timber is carried out on the three species. El empleo de la madera en la construcción en Espa a adolecía de la inexistencia de procedimientos de cálculo normalizados. La reciente adopción y publicación del Eurocódigo 5 obliga al empleo de los valores característicos del material en el cálculo estructural de la madera por el método de los elementos finitos. Se presentan los resultados de la caracterización mecánica de la madera aserrada de tama o (150x50x3.000 mm) y usos estructurales de "Pinus sylvestris, P. radiata y P. pinaster" de diferentes procedencias, llevada a cabo en el Centro de Investigación Forestal (CIFOR) del INIA. Se aportan los valores característicos y clases de resistencia que corresponden a las clases de calidad definidas en la norma UNE 56544. Se efectúa una comparación y análisis de los resultados obtenidos, extrayendo conclusiones respecto del diferente comportamiento observado para las cuatro especies. Se analiza la adecuación de la norma de clasificación visual de la madera aserrada UNE 56544para las tres especies.
中国锯材进口变化及影响因素的实证分析
An Empirical Analysis on China’s Sawn Timber Import and Its Influencing Factors
 [PDF]

李秋娟,陈绍志,赵荣
- , 2018, DOI: 10.3969/j.issn.1001-7461.2018.04.45
Abstract: 分析中国锯材进口变化趋势及影响因素,为优化锯材进口贸易结构和保障国内木材供需平衡提供科学依据。运用1997-2015年中国与10个主要锯材进口贸易国的面板数据,在传统贸易引力模型的基础上,根据锯材进口贸易的特点,引入新的变量构建扩展的贸易引力模型,分析了影响中国锯材进口的主要因素及其影响方向和程度。结果表明,贸易伙伴国的国内生产总值GDPjt的估计系数为0.312,表明在其他条件不变的情况下,贸易伙伴国的国内生产总值每增长1%,中国锯材进口量将增加0.312%;两国之间的距离Dijt的估计系数为-1.765,说明中国与锯材进口来源国之间的距离每增长1%,中国锯材进口量将减少1.765%;两国人均蓄积量的差异ADFVijt的估计系数为0.451,说明两国人均森林蓄积差异每增加1%,中国锯材进口量将增加0.451%;中国经济增长对锯材进口影响并不明显,主要靠木材下游产业出口的拉动;进口锯材是出口木家具的主要原材料,中国木家具出口量FEit的估计系数为0.413,说明中国木家具出口量每增加1%,中国锯材进口量将增加0.413%;两国之间汇率Rijt的估计系数为0.037,说明人民币对锯材进口贸易国货币汇率每升值1%,中国从贸易国进口锯材量将增加0.037%;中国实施的天然林保护政策以及贸易伙伴国实施的原木出口限制政策均刺激了中国锯材进口量的增长。因此,应从促进锯材市场多元化、降低贸易运输成本、扩大植树造林、提高营林技术以及木材综合利用率等方面着手优化锯材进口贸易结构,降低锯材对外依存度,保障国内木材供需平衡。
With the promotion of natural forest protection policy,the shortage of China?s timber and the increase of imports of sawn timber have gradually been attracted the attention of the industry.Using the panel data of China and the top 10 importing countries of sawn timber during 1997 to 2015,the extended gravity model was established with the introduction of new variables based on classic gravity model and the characteristics of China?s sawn timber import,and the influencing factors of China’s sawn timber import trade and its influencing direction and degree were analyzed in this paper.The empirical results showed as follows.If other conditions remain unchanged,each increase of 1% per capital gross domestic product (GDP) of trading partners will result an 0.312% increase of China’s sawn timber imports; each increase of 1% of the distance between China and trading partner will reduce 1.765% of China’s sawn timber imports; each increase of 1% of the difference of per capita forest volume between China and trade partners will increase 0.451% of China’s sawn timber imports.China’s economic growth on the impact of sawn timber imports was not significant,and the sawn timber imports was mainly driven by the exports of downstream timber industry.Imported sawn timber was the important material of exported wooden furniture,and each increase of 1% of China’s wooden furniture exports will increase 0.413% of China’s sawn timber imports; each increase of 1% of currency exchange rate between China and trading partners will increase 0.037% of China’s sawn timber imports.The implementations of China’s natural forest protection policy and the log export restriction policy of the trade partners stimulated the growth of China’s imports of sawn timber.Furthermore,some recommendations were proposed to optimize the import trade structure of sawn timber,reduce the foreign trade dependence and guarantee the balance of
Eucalipto, madeira serrada, metodologia de amostragem, regress o multivariada. Log sampling of Eucalyptus grandis trees submitted to selection for sawn timber and energy purposes Amostragem de toras de árvores de Eucalyptus grandis selecionadas para finalidades de serraria e energia
Paulo Eduardo Telles dos Santos,Osmir José Lavoranti,Laurindo Salante
Pesquisa Florestal Brasileira , 2010, DOI: 10.4336/2012.pfb.54.53
Abstract: By the assessment of ten technological traits of eucalypt wood for sawn timber and energy purposes, it was developed a multivariate statistical procedure in order to determine the sequence of logs to be sampled, in such a way to represent all statistical variation contained within the tree and, accordingly, to establish the appropriate sampling intensity. In the present work, it was used a total of 40 logs from four trees of Eucalyptus grandis provenance Concórdia-SC aged 18 years. By using principal components regression analysis and stepwise selection techniques, it was showed that only two logs, corresponding to the first (0.05 m to 2.60 m) and fourth (8.85 m to 11.40 m) positions into the tree, contained 99.2 % of the total variation detected originally. In the case of adopting a single log, the recommendation was over the fourth log, which represented 97.5 % of the total amount of the original variation. For the referred population, the statistical procedure contributed substantially to reduce the high time-consuming and financial costs that are normally associated to studies oriented to this goal, without affecting the original statistical information exhibited by the whole group of logs that would be usually sampled. A partir da avalia o de dez características tecnológicas de madeira de eucalipto para fins de serraria e energia, desenvolveu-se procedimento estatístico multivariado para se determinar a seqüência de toras a ser amostrada, de forma a representar acumuladamente toda a varia o estatística presente na árvore e, com isso, estabelecer a intensidade adequada de amostragem. Neste estudo, foram utilizadas 40 toras oriundas de quatro árvores de Eucalyptus grandis aos 18 anos de idade procedentes de Concórdia, SC. Com o uso de técnicas de regress o multivariada de componentes principais e sele o por etapas, chegou-se à conclus o que amostrandose apenas duas toras, correspondentes à primeira (0,05 m a 2,60 m) e quarta (8,85 m a 11,40 m) posi es dentro da árvore, foi possível abranger 99,2 % de toda a varia o inicialmente detectada. No caso de optar-se por utilizar apenas uma única tora, a indica o recaiu para a quarta tora da árvore, a qual representou 97,5 % de toda a varia o contida nos dados originais. Para a referida popula o, o procedimento estatístico adotado evidenciou a possibilidade de se reduzir substancialmente os elevados gastos, de tempo e de recursos financeiros, associados a avalia es dessa natureza, sem comprometer a qualidade da informa o estatística original contida em todas as toras que seriam convencionalmente a
Ensayos de eficacia cuarentenaria de tres formulaciones de antimanchas comercializadas en Chile para un proceso simulado de exportación de madera aserrada de Pinus radiata Quarantine efficacy of three anti-bluestain formulas sold in Chile, in a simulated export process involving sawn Pinus radiata timber  [cached]
ISABEL VIVES,SANDRA IDE,HERNAN PEREDO
Bosque (Valdivia) , 2004,
Abstract: Se ensayaron tres productos antimancha en madera aserrada de Pinus radiata tanto en la Octava como en la Décima Región de Chile. Los productos fungicidas fueron Combo Antiblu (mezcla de Antiblu 375 y Antiblu CC), Wolsin FL 12215 y Sinesto B. De los resultados obtenidos se pudo comprobar que los productos utilizados fueron más efectivos en la Décima que en la Octava Región. De los tres productos ensayados Combo Antiblu tuvo el mejor resultado en ambas regiones al proteger la madera. Three anti-sapstain products were tested on sawn Pinus radiata timber in the Eighth as well as in the Tenth Regions of Chile. The fungicide products were Combo Antiblu (a mixture of Antiblu 375 and Antiblu CC), Wolsin FL 12215 and Sinesto B. Results showed that the products were more effective in the Tenth Region than in the Eighth Region. Of the three products tested, Combo Antiblu had the best characteristics in both Regions.
Management analysis of the timber industry in Lavras, Minas Gerais state  [PDF]
Rosa Maria Miranda Armond Carvalho,Lourival Marin Mendes,Rommel Noce,Rafael Farinassi Mendes
CERNE , 2009,
Abstract: This study analyzed the sawn timber industry in Lavras county MG state with emphasis on aspects of contextualand structural subsystems. A survey was conducted with organizations composing the local timber production chain to establishagreement rating measures related to the aspects in question. It was noted that, regardless of their position in the timber productionchain, organizations did not present significant differences concerning adjustment and development of contextual and structuralsubsystems.
Brazilian sawn wood price and income elasticity  [PDF]
Rommel Noce,José Luiz Pereira de Rezende,Agostinho Lopes de Souza,Lourival Marin Mendes
CERNE , 2010,
Abstract: This study estimated the sawn wood demand price and income elasticity. Specifically it was estimated the priceelasticity of sawn wood, the cross price elasticity of wood panels and the income elasticity of Brazilian GDP. A log-log model withcorrection through outline of the mobile average (MA(1)) was used, adjusted for the period of 1971 to 2006, which showed to bestable, with satisfactory significance levels. It was observed that sawn wood demand is inelastic in relation to price and elastic inrelation to income.
Estimates of genetic parameters of wood traits for sawn timber production in Eucalyptus grandis
Santos, Paulo Eduardo Telles dos;Geraldi, Isaias Olívio;Garcia, José Nivaldo;
Genetics and Molecular Biology , 2004, DOI: 10.1590/S1415-47572004000400017
Abstract: in this study, the breeding perspectives of 41 open-pollinated progenies of eucalyptus grandis were evaluated based on their wood traits. the progenies were distributed in two experiments in a randomized complete block design, with three replicates and linear plots containing six plants each. the traits were assessed at eight years of age. two trees from each plot were selected for this assessment based on better growth, stem form and phytosanity. significant differences in basic density, sapwood/heartwood ratio, bowing, specific gravity, parallel compression and static bending were detected among the progenies. these traits were potentially promising for breeding programs, with heritability coefficients that varied from 0.34 to 0.61 on a progeny mean basis. there was no genetic variation in the moisture content, board end-splitting, log volume under bark, log eccentricity, bark content, crooking, and shear strength of the progenies. intermediate to highly significant genetic correlations were detected among the physical and mechanical properties, as well as between pairs of traits such as basic density and log end-splitting, basic density and bowing, specific gravity and bowing, sapwood/heartwood ratio and bowing, log volume and bowing, and log volume and log end-splitting. these results show that the levels of growth stress in trees can be reduced by selection using indirect traits such as the sapwood/heartwood ratio and bowing.
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