Eigenschaften und Einsatz von Nadelstarkholz | Characteristics and use of large diameter fir and spruce wood

2006 ◽  
Vol 157 (12) ◽  
pp. 530-538
Author(s):  
Gero Becker ◽  
Gerald Bender ◽  
Michael Leenen ◽  
Udo Hans Sauter

The forestry goal of producing large diameter wood seems contradictory to the sawmill industries goal of small to medium diameter wood. Amongst other things, the insufficient knowledge of wood properties of large diameter wood has led to examinations to finding a better way to evaluate wood quality. Based on outer characteristics the quality of fir and spruce round wood has been described and interpretated. At lower parts of the stems a wide variation of inner quality was remarked during the processing of large diameter softwood. Most of the wood is of medium quality; the lowest part of the stems, especially for spruce, was often found to have been damaged by rot caused by logging. Fir and spruce timber have a similar result in quality grading. In conclusion, it must be said that a successful judgement of timber quality based on outer characteristics of the stems is only partially possible.

2006 ◽  
Vol 157 (12) ◽  
pp. 551-555
Author(s):  
Udo Hans Sauter ◽  
Michael Leenen ◽  
Christian Pfeil ◽  
Maria Hehn

Stocks of large dimension wood continue to increase, especially of medium quality classes B and C. Apart from newly built major sawmills, small and medium sized sawmills are also beginning to specialise in the processing of large diameter softwood of 3 – 6 m in length. In its turn, this is leading to changes in wood-logging techniques and quality grading. Different methods of harvesting are presented, as well as a detailed discussion of wood-grading methods.


1995 ◽  
Vol 71 (4) ◽  
pp. 473-478
Author(s):  
Y. H. Chui

Norway spruce [Picea abies (L.) Karst.] is one of the major non-native softwood species in the Maritimes. A project was undertaken to evaluate the grade yields and mechanical properties of Norway spruce. The project also provided comparative information on the wood quality of two Norway spruce provenances from Germany and Poland. Four plantations were selected for the study with two of these plantations containing trees of known provenances. One plantation was mature and the other three were juvenile. In total, 530 pieces of lumber and the same number of matched small clear specimens were tested for bending properties. Prior to testing, the lumber was visually graded according to both British and Canadian specifications. Quality of lumber varied significantly between sites. Lumber from the Polish provenance had slightly better mechanical properties than that from trees of the German provenance. Compared with published information, the plantation-grown Norway spruce had lower clear wood bending properties and specific gravity than primary eastern Canadian spruce species and balsam fir, and natural Norway spruce grown in Europe. Key words: Norway spruce [Picea abies (L.) Karst.], wood quality, bending properties, grade yield


2010 ◽  
Vol 218 (3) ◽  
pp. 175-184 ◽  
Author(s):  
Rüdiger Mutz ◽  
Ute Seeling

The purpose of this article is to discuss new methodological developments, starting with Schilling and Hogge (2001) , aimed at establishing a nomothetic version of the Brunswikian lens model based on multilevel models (multilevel latent class regression). This genuinely person-oriented approach simultaneously allows the idiographic assessment of individual judgment processes and the nomothetic examination of evidence of generalization across individuals. Data of a pilot project on forest persons’ subjective judgment of the quality of wood (“Forstlicher Götterblick”) are used to demonstrate the proposal: In a paper-pencil test, 29 forest persons (forestry students and foresters) each estimated the internal wood quality of 40 trees on a 6-point rating scale using information provided about six well-known external wood properties for each tree. Two judgment strategies were identified (“Take-The-Best” and random) which could also be assigned to two different types of subjects (“novices” vs. “experts”). Summarizing, this approach combines both person-oriented and variable-oriented concepts.


IAWA Journal ◽  
1986 ◽  
Vol 7 (4) ◽  
pp. 399-404 ◽  
Author(s):  
J. A. Evertsen ◽  
M. P. Mac Siurtain ◽  
J. J. Gardiner

In this preliminary study, the influence of industrial emission on the wood quality of Norway spruce was evaluated. Intrinsie wood quality determining properties: ring width (RW), mean annual density, percentage annual 1atewood and the product of (RW × (maximumminimum density)) appear to be affected by the emissions of a fertiliser factory adjoining the stands studied. Fluctuations in the performance of these intrinsic wood properties coincide with the start of production by the factory and a change in the manufacturing process.


2006 ◽  
Vol 157 (12) ◽  
pp. 546-550
Author(s):  
Stefan Möhringer

Modern sawing techniques focus mainly on small and medium diameter round wood due to the easier and higher-performing sawing ability. This evolution was mainly driven by chippercanter sawing technology, which allowed increasing sawing feed speeds. Nowadays, increasing competition between sawmills concerning the raw material turns the focus once again towards large diameter round wood. This contribution intends to give a survey of state-of-the-art sawing technologies, pointing out their specific advantages and inconveniences. In conclusion, the article shows that available sawing technologies can process large diameter round wood in a cost efficient way.


Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 353
Author(s):  
Kun-Cheng Ke ◽  
Ming-Shyan Huang

Conventional methods for assessing the quality of components mass produced using injection molding are expensive and time-consuming or involve imprecise statistical process control parameters. A suitable alternative would be to employ machine learning to classify the quality of parts by using quality indices and quality grading. In this study, we used a multilayer perceptron (MLP) neural network along with a few quality indices to accurately predict the quality of “qualified” and “unqualified” geometric shapes of a finished product. These quality indices, which exhibited a strong correlation with part quality, were extracted from pressure curves and input into the MLP model for learning and prediction. By filtering outliers from the input data and converting the measured quality into quality grades used as output data, we increased the prediction accuracy of the MLP model and classified the quality of finished parts into various quality levels. The MLP model may misjudge datapoints in the “to-be-confirmed” area, which is located between the “qualified” and “unqualified” areas. We classified the “to-be-confirmed” area, and only the quality of products in this area were evaluated further, which reduced the cost of quality control considerably. An integrated circuit tray was manufactured to experimentally demonstrate the feasibility of the proposed method.


1996 ◽  
Vol 1996 ◽  
pp. 138-138
Author(s):  
S. Kavanagh ◽  
P.B. Lynch ◽  
P.J. Caffrey ◽  
W.D. Henry

The benefits of creep feeding in a 3 - 4 week weaning system is uncertain. Sow milk yield peaks at 3 - 4 weeks postpartum and the need for supplementary feed to maintain growth rates of suckling pigs is minimal. The objective of this study was to quantify creep feed intake by suckling pigs and to assess the effect of creep feeding on piglet growth and weight at weaning when weaned at 26.0 (s.e. 0.6) days of age.The results reported here were obtained by combining data from 296 litters of suckling pigs on 5 creep feeding trials. The five trials involved comparison of diets and management systems as follows: (A) effect of quality of creep feed (high quality starter diet vs medium quality starter diet vs a pelleted cooked cereal); (B) comparison of meal and pelleted diets; (C) the effect of form (reconstituted calf milk replacer - 20 % dry matter vs solid pellet vs peat primer offered with a solid pellet); (D) effect of feed freshness (fresh creep vs 30 day old creep vs 60 day old creep feed); (E) effect of creep feeding piglets on pre-weaning performance.


2021 ◽  
Vol 5 (2) ◽  
pp. 149
Author(s):  
Halija Halija ◽  
Jufri Karim ◽  
Sawaludin Sawaludin

Abstrak: Penataan ruang kawasan pesisir harus dipandang sebagai upaya dalam peningkatan kualitas kawasan fisik dan kesejahteraan masyarakat.Permasalahan dalam penelitian ini, yaitu tidak berfungsinya drainase secara optimal belum terdapatnya sarana mandi, cuci, kakus (MCK) dan kondisi faktor fisik rumah yang masih berstruktur kayu dan semi permanan. Tujuan dari penelitian ini, yaitu: (1) menganalisis kondisi fisik permukiman kawasan pesisir; (2) menganalisis kualitas permukiman kawasan pesisir dan merumuskan strategi pemecahan masalah permukiman kawasan pesisir Kecamatan Marobo Kabupaten Muna. Metode penelitian ini, yaitu: (1) kondisi fisik permukiman diketahui dengan melakukan interpertasi citra satelit Google Earth:(2)kualitas permukimandiketahui denganpendekatan keruangan dengan menggunakan Sistem Informasi Geografi pada aplikasi ArcGIS dengan melakukan teknik analisis scoring. Hasil penelitian ini menunjukkan bahwa: (1)nilai kelayakan bangunan rumah hunian Desa Marobo, yaitu 70% dengan luas lantai >7,2, skor  5 bisa di kategorikan cukup luas, kemudian kelurahan Paroha 50 %, dengan luas lantai >7,2 skor  3,  Kelurahan Wadolau nilai kelayakan bangunan rumah hunian, yaitu 30% dengan luas lantai >7,2 skor  2  dan terakhir Kelurahan Tapi-Tapi nilai kelayakan bangunan rumah hunian, yaitu <10% dengan luas lantai>7,2 skor  1, sehingga bisa di kategorikan cukup kecil/sempit; (2) permukiman penduduk di Pesisir Desa Tapi-Tapi, Desa Wadolau, dan Desa Marobo didominasi oleh rumah nelayan, dengan luas pekarangan dan luas rumah tinggal cukup kecil/sempit.  Kondisi fisik rumah tinggal penduduk di Kecamatan Marobo termasuk kategori semipermanen yang tercermin dari jenis bahan dinding rumah yang mayoritas terbuat dari  papan kayu berkualitas sedang.Kata kunci: kondisi fisik, kualitas permukiman, kawasan pesisirAbstract: Coastal spatial planning must be seen as an effort to improve the quality of physical areas and the welfare of the community. The problem in this study are the drainage does not function optimally, among others there are no facilities for bathing, washing, latrines and the physical condition of the house which is still structured in wood and semi-permanent. The purpose of this study are: (1) to analyze the physical condition of the coastal area settlement in Marobo District Muna Regency; (2) to analyze the quality of coastal area settlements and formulate strategies for solving the problem of coastal area settlements in Marobo District Muna Regency. The research methods are: (1) the physical condition of the settlement is known by interpreting Google Earth satellite imagery; (2) settlement quality is known by spatial approach using Geographic Information Systems with ArcGIS by conducting a scoring analysis technique. The results of this study are: (1)the feasibility value of Marobo Village residential building is 70% with a floor area >7,2 score 5 can be categorized quite broadly, Paroha Village 50%, with a floor area >7,2 score 3 Wadolau Village the feasibility value of residential building is 30% with a floor area >7,2, score 2 and lastly the Tapi-Tapi Village feasibility value of residential buildings is <10% with a floor area >7,2 score 1 so that it can be categorized quite small/narrow; (2) the residential settlements in the Tapi-Tapi Village, Wadolau Village and Marobo Village are dominated by fishermen's houses, with a large yard area and a small/narrow residential area. The physical condition of resident houses in Marobo District belongs to the semi-permanent category, which is reflected in the type of wall material of the house which is mostly made of medium quality wood plasterKeywords: physical condition, quality of settlements, coastal area


2016 ◽  
Vol 2016 ◽  
pp. 1-7
Author(s):  
Jian Li ◽  
Yiming Fang ◽  
Jiyong Tang ◽  
Hailin Feng ◽  
Xiongwei Lou

Stress wave based techniques have been developed for evaluating the quality of the wooden materials nondestructively. However the existing techniques have some shortcomings due to the significant variation of the wood properties and are now in need of updating. There are also stress wave based instruments which have been widely used for nondestructive testing of wood. But most of them are inflexible and unsuitable for the tentative studies. This paper proposed and implemented a wood nondestructive testing platform based on NI virtual instrument. Three wood nondestructive testing methods, including peak time interval measurement, cross-correlation, and spectrum analysis, were also tested on this platform with serious decay sample, early decay sample, and defect-free sample. The results show that new methods can be verified easily and the researches of wood nondestructive testing will be accelerated with the designed platform.


2013 ◽  
Vol 43 (1) ◽  
pp. 1-6 ◽  
Author(s):  
S.G. Kennedy ◽  
A.D. Cameron ◽  
S.J. Lee

The trend towards shorter rotations in planted conifer stands has resulted in a reduction in the proportion of mature wood relative to juvenile core wood, raising concerns that the mechanical performance of sawn battens will be affected. The potential to improve the wood quality of the juvenile core of Sitka spruce (Picea sitchensis (Bong.) Carrière) without compromising growth rate was investigated. Rapid and inexpensive indirect methods of assessing wood properties on standing trees using a Pilodyn gun and acoustic velocity were compared with direct measurements made on wood samples cut from the juvenile core. Strong genetic correlations were observed between Pilodyn gun values and direct measures of density (–0.76) and between the square of acoustic velocity and modulus of elasticity (0.73). The genetic correlation between the square of acoustic velocity and microfibril angle was also strong (–0.84). These results suggest that indirect assessments of wood properties within juvenile core wood are sufficiently reliable for these techniques to be used in the Sitka spruce breeding programme. Although a strong negative genetic correlation between diameter at breast height and density was noted (–0.79), sufficient variation exists within the breeding population to select families with both good growth rate and high modulus of elasticity wood.


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