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  • 1.
    Johansson, Jimmy
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Sandberg, Dick
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Automatic sorting of sawn birch: Defect detection possibilities on sawn and planed wood surfaces2010Ingår i: Hardwood research and utilisation in Europe: New Challanges / [ed] Robert Nemeth and Alfred Teischinger, Sopron: University of West Hungary Press , 2010, 206-213 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the production of sawn hardwood a critical processing step is the quality grading. The grading has normally been handled manually in the hardwood sawmills. The process has been labour intensive and a problematic working environment. With the help from existing scanning technology it is possible to automate the process with several benefits as a result. These are e.g. a decreased need of labour, a better working environment and the possibility to use more complicated grading rules. Thereby the wood could be used in a more optimal way with both cost and environmental benefits.

    One problem when grading hardwood is that camera and laser based scanning technology has mainly been used on planed surfaces. Normally the quality grading in hardwood sawmills is performed before planing. The wood may then be cross-cutted to components before planing in order to minimise the volume losses because of deformations of the wood pieces.

    In order to investigate the possibilities to scan the sawn wood before planing rip-sawn birch boards (Betula pubescens Ehrh., Betula pendula Roth.) was scanned before and after planing the wood. The used scanner was a commercial system for automatic sorting of wood. Before the scanning it was estimated that the sawn surfaces exposed to the surrounding environment during drying would not generate any usable results from the scanning. Therefore only the two rip-sawn surfaces were used for evaluation before and after planing. The evaluation was made by comparing the results from the quality grading before and after the planing based on grading rules used by Swedish hardwood sawmill. The results show that there are possibilities to grade the birch wood before planing. The study, however, shows that the scanner has difficulties in detecting small colour variations as brown streaks and fresh knots. It is also difficult to detect fibre angle deviations because of loose fibres on the sawn surface. The possibilities to scan the birch wood are thereby related to the grading rules, i.e. if the mentioned quality parameters are allowed or not.

  • 2.
    Johansson, Jimmy
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Kifetew, Girma
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    CT-scanning and modelling of the capillary water uptake in aspen, oak and pine2010Ingår i: European Journal of Wood and Wood Products, ISSN 0018-3768, Vol. 68, nr 1, 77-85 s.Artikel i tidskrift (Refereegranskat)
  • 3.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Chavenetidou, Marina
    Aristotle University, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Effect of cambium age and ring width on density and fibre length of black locust and chestnut wood2010Ingår i: Wood research, ISSN 1336-4561, Vol. 55, nr 3, 25-36 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The relationship between wood density (WD) and fibre length (FL) with cambium age (CA) and ring width (RW) was studied in two ring-porous species, black locust and coppice-grown chestnut, collected in the Sithonia Peninsula, Chalkidiki, Greece. Using regression analysis methods, models of WD and FL in relation to CA and RW were obtained. It was found that the effect of CA and RW on WD and FL was similar for both species examined. WD of black locust and chestnut was predicted better through a model using CA and RW. A model for FL variations was also obtained with CA and RW and was more accurate than the simple models based on the two factors, CA and RW, separately. The multiple regression models suggested that the use of cambial age of growth rings together with their width might explain better their effects on WD and FL of black locust and chestnut.

  • 4.
    Johansson, Jimmy
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Sandberg, Dick
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Improved use and production of hardwood with the PrimWood Method2010Ingår i: Broadleaved forests in southern Sweden: management for multiple goals / [ed] Magnus Löf , Jörg Brunet, Leif Mattsson och Mats Nylinder, Oxford: Wiley-Blackwell, 2010, Vol. 53, 51-59 s.Kapitel i bok, del av antologi (Refereegranskat)
  • 5.
    Devine, Åsa
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Internationalization and Performance among Small and Medium-sized Firms: A study of furniture producers in Sweden2010Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Furniture production in Sweden still exists on a comparably small scale. The majority, or more than 99 percent, of all furniture producers in Sweden are small and medium sized enterprises (SMEs) with less than 250 employees. Despite their size, these firms are, to a large extent, involved in export. This is fully in line with the accelerating trend of internationalization found among firms of all sizes. However, research focused on internationalization has been primarily concentrated on larger firms, which is unfortunate considering that the vast majority of all firms within the European Union can be described as SMEs. The purpose of this research is, therefore, to extend our understanding of internationalization and performance among small and medium sized firms by explaining export involvement and performance among small and medium sized furniture producers in Sweden.

    This research is completed within the theoretical framework of the modified PSE model, which consists of four components: perception of export barriers, strategy competence, export involvement, and performance. A quantitative survey was conducted among 324 firms, yielding a response rate of 56 percent. The empirical data was analyzed using the methods of multiple linear regression, logistic regression, and ordinal regression.

    The result suggests that strategy competence, measured in terms of relatedness and market knowledge, explains the main export mode and performance among exporting SMEs. In addition, main export mode seems to explain performance. The main findings of this research are visualized through a new model, SCEMPER. Another finding is that barriers originating with the owner/key decision-maker of a firm seem to prevent firms from becoming involved in export. In addition, attitude towards export and the age of the firm appear to be important determinants of export involvement and performance among SMEs.

  • 6.
    Fagerberg, Nils
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Kontinuitetsskogsbruk2010Ingår i: Åter, ISSN 1650-3546, nr 4, 14-15 s.Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Det finns alternativ för skogsägare som inte vill skapa ett kalhygge inpå husknuten och som vill värna de mossor, lavar, svampar och skalbaggar som hotas av det moderna skogsbruket. Kontinuitetsskogsbruk innebär att man hela tiden behåller ett trädskikt i den skötta skogen. Genom att bedömma och styra trädens inbördes förhållanden kan man använda skogens egna mekanismer till att med små medel få mycket virke till bra kvalitet ur sin skog -samtidigt som man har den kvar.

  • 7.
    Konnerth, Johannes
    et al.
    BOKU-University of Natural Resources and Applied Life Sciences, Austria.
    Eiser, Martina
    Competence Center for Wood Composites and Wood Chemistry, Austria.
    Jäger, Andreas
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Follrich, Jürgen
    Competence Center for Wood Composites and Wood Chemistry, Austria.
    Ters, Thomas
    BOKU-University of Natural Resources and Applied Life Sciences, Austria.
    Hansmann, Christian
    Competence Center for Wood Composites and Wood Chemistry, Austria.
    Wimmer, Rupert
    ood Technology and Wood-based Composites Unit, Germany.
    Macro- and micro-mechanical properties of red oak wood (Quercus rubra L.) treated with hemicellulases2010Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 64, nr 4, 447-453 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Red oak wood (Quercus rubra L.) samples were submitted to an enzymatic treatment with a commercial mixture of hemicellulases aiming at the selective depolymerization and removal of the hemicelluloses. Mechanical properties of treated samples were characterized and compared with untreated samples at two hierarchical levels. At the macrolevel, tensile properties revealed to be less sensitive to degradation of the cell wall matrix compared to compression and hardness properties. Results obtained through indentation at the microlevel indicated that hardness and the so-called reduced modulus of treated wood were significantly lowered. Accordingly, hardness and reduced elastic modulus have proven to be most sensitive to modification of the cell wall matrix by reducing the content of hemicelluloses. It is proposed that transversal and shear stresses, which are mainly carried by the cell wall matrix, are additional parameters having strong effects on elastic modulus obtained by nanoindentation. Micromechanical modeling was employed to confirm the observed changes. There is consistency between the measured and the modeled properties, obtained at both the microlevel and the macrolevel of wood.

  • 8.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Hellmich, Christian
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Multiscale Microporomechanics of Softwood: Applications and Experimental Model Validation2010Ingår i: IV European Conference on Computational Mechanics (ECCM 2010), Paris, France: European Community on Computional Methods in Applied Sciences (ECCOMAS), 2010Konferensbidrag (Övrigt vetenskapligt)
  • 9.
    Blom, Åsa
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Thörnqvist, Thomas
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Bergström, Mikael
    Outdoor exposure of untreated Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst) wood samples2010Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, Vol. 5, nr 3-4, 204-210 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Untreated Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) samples were exposed above ground in a durability test for six years. The samples consisted of three pieces of wood, 22x95x500 mm, screwed together; two pieces lengthwise with a third piece overlapping. Weight was measured, to calculate moisture content (MC), and samples checked regularly for cracks and fungal growth. Parameters investigated were heartwood/sapwood (pine), annual ring orientation (spruce), stand site, annual ring width and density.

    Stand site, annual ring width or density had no influence on MC or fungal growth for neither pine nor spruce. Spruce samples with vertical annual rings had lesser amounts of cracks than samples with horizontal annual rings.

    Regarding pine sapwood samples, they showed high MC and large amount of rot fungi, while heartwood had lower MC and no rot. Most spruce samples were similar to pine heartwood, except from a few samples that had high MC and fungal growth. Those were all sawn from the outer part of the log. Therefore, it can be stated that spruce sawn from the inner part has almost the same properties as pine heartwood while spruce from the outer part of the log has properties similar to pine sapwood.

  • 10.
    Mantanis, George
    et al.
    Laboratory of Wood Technology, Greece.
    Adamopoulos, Stergios
    Technological Education Institute of Larissa, Greece.
    Rammou, Ekaterina
    Laboratory of Wood Technology, Greece.
    Physical and mechanical properties of Pinus leucodermis wood2010Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, Vol. 5, nr 1, 50-52 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present work reports on the main physical and mechanical properties of Pinus leucodermis mature wood, one of the least studied coniferous species in south-east Europe. Pinus leucodermis heartwood specimens were found to have average density values of 0.73 g cm−3 at equilibrium moisture content of 11.5% and average density of 0.64 g cm−3 under oven-dry conditions. The overall tangential shrinkage was 3.4% and the radial shrinkage was 1.9%. The modulus of rupture was on average 77 N mm−2, while the static modulus of elasticity averaged 7087 N mm−2. The hardness of P. leucodermis heartwood using the modified Janka test was 33.4 N mm−2 in the transverse direction and 48.0 N mm−2 in the longitudinal direction, while its compression strength parallel to grain was approximately 41.6 N mm−2.

  • 11. Bader, Thomas K.
    et al.
    Hofstetter, Karin
    Technische Universität, Austria.
    Pilzabbau von Holz: Quantifizierung des Steifigkeitsverlusts auf Basis von mikromechanischen Überlegungen2010Ingår i: Wiener Holzschutztage 2010: 25. - 26. November 2010, Wien, Wien: Wiener Holzschutztage , 2010, Vol. 28, 50-55 s.Konferensbidrag (Övrigt vetenskapligt)
    Abstract [de]

    Pilzbefall bewirkt eine Zersetzung des Materials durch Mikroorganismen und damit unweigerlich auch eine Veränderung des mechanischen Verhaltens von Holz. Die Auswirkung der mikrostrukturellen Änderungen auf makroskopisch beobachtbare mechanische Materialkennwerte wie Steifigkeit und Festigkeit lassen sich mittels Mehrskalenmodellierung abschätzen und quantifizieren. Die Eignung solcher Mehrskalenmodelle als Prognosewerkzeuge für Dauerhaftigkeitsbetrachtungen wurde im WoodWisdom-Netzwerk „WoodExter“ im Rahmen eines umfangreichen Testprogramms untersucht. Es wurde dabei sowohl ein Braunfäule verursachender Pilz (Gloephyllum trabeum) als auch ein Weißfäule verursachender Pilz (Trametes versicolor) verwendet. Die Vorgehensweise sowie die gewonnenen Einblicke und Erkenntnisse sind in diesem Beitrag zusammengefasst. Nach einer Kurzbeschreibung der hierarchischen Struktur von Holz und deren Modifikation durch Pilze folgt ein Abriss über die verwendeten Verfahren der Mehrskalenmodellierung. Der Schwerpunkt liegt in der Präsentation der Ergebnisse sowie der experimentellen Validierung des Modells durch Vergleich von Messwerten mit zugehörigen Modellvorhersagen. Schließlich werden im Ausblick mögliche Anwendungen der Modellierung skizziert. 

  • 12.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Hellmich, Christian
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Poromechanical scale transitions of failure stresses in wood: from the lignin to the spruce level2010Ingår i: Zeitschrift für angewandte Mathematik und Mechanik, ISSN 0044-2267, E-ISSN 1521-4001, Vol. 90, nr 10-11, 750-767 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wood strength is highly anisotropic, due to the inherent structural hierarchy of the material. In the framework of a combined random-periodic multiscale poro-micromechanics model, we here translate compositional information throughout this hierarchy into the resulting anisotropic strength at the softwood level, based on “universal” elastic properties of cellulose, hemicellulose, and lignin, and on the shear strength of the latter elementary constituent. Relating, through elastic energy-derived higher-order strains in a poromechanical representative volume element, the (quasi-)brittle failure of lignin to overall softwood failure, results in a macroscopic microstructure-dependent failure criterion for softwood. The latter satisfactorily predicts the biaxial strength of spruce at various loading angles with respect to the grain direction. The model also predicts the experimentally well-established fact that uniaxial tensile and compressive strengths, as well as the shear strength of softwood, depend quasi-linearly on the cell water content, but highly nonlinearly on the lumen porosity.

  • 13.
    Hameed, Mahmood
    et al.
    Damascus University, Syria.
    Al-Douhji, Ziad
    Preliminary Study for the Possibility of using Infra-density to determinate the Density of Medium Density Fiber Board (MDF).2010Ingår i: Minia Journal of Agricultural Research and Development., ISSN 1110-0257, Vol. 32, nr 2, 195-209 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This investigation has established the possibility of using Infra-density to determine the density of medium density fiber board (MDF). The statistical analysis has proved that there is a high significant correlation between the values of density and infra-density. There is a homogeneity between the method of density and infra-density measurements. Whereas the value of the correlation coefficient  reached 0.85 and the mean of density 0.667 g/cm3 while the mean of infra-density was 0.668.

     

  • 14.
    Hameed, Mahmood
    Damascus University, Syria.
    Production of organic fertilizer (compost)  via fermentation of various agricultural wastes2010Ingår i: Minia Journal of Agricultural Research and Development, ISSN 1110-0257, Vol. 30, nr 2, 259-281 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The wastes of vineyard and olive pruning and olive pulp are abundant in Syria.  Therefore, these wastes were used as raw materials for compost production. The effect of microorganism (yeast) on fermentation process under aerobic and anaerobic condition was studied. The Chemical characteristics of the resulting compost were measured.

    The results showed that treatment of the wastes with yeast during fermentation process recorded superiority in the chemical and physical properties of the compost as compared to those without yeast addition. This may indicate the role played by yeast in stimulating the other microorganisms which are responsible for decomposition of wastes. The chemical properties of the compost produced by fermentation of pruning wastes treated with yeast were much better than the other treatments.

     

  • 15.
    Gustafsson, Åsa
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Rask, Lars-Olof
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Proposing a Research Agenda for Swedish Sawmill Distribution Channel Challenges2010Ingår i: Presented at SSFE 2010 / [ed] Bo Jellesmark Thorsen, 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose; The purpose of this study is to identify distribution channel research needs given the variety of distribution channel challenges among Swedish sawmill companies.

    Design / methodology / approach; Explorative case study research

    Findings: The paper proposes a typology of sawmill distribution channel challenges, as well as aligns research needs with distribution channel type. The typology is based on i) number of sawmill units within the firm, in combination with ii) distribution channel heterogeneity. Significant management decisions and research needs are identified for the different types.

    Research limitations / implications; This research makes tentative statements regarding typology of sawmill distribution channel challenges and potential research needs in the Swedish sawmill industry with regards to the respective typology. However, further research is needed in order to validate these results.

    What is original/value of paper: This paper focus on the sawmill industry distribution channels, which is a neglected but important area for sawmill’s competitive advantage. The paper also contributes to research by applying contingency theory and typology as an approach to deal with the variety of sawmills distribution channel challenges.

    Keywords; Typology, distribution channel challenges, research needs, and Swedish sawmill industry

  • 16.
    Girhammar, Ulf Arne
    et al.
    Umeå universitet, Institutionen för tillämpad fysik och elektronik.
    Källsner, Bo
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Daerga, Per Anders
    Umeå universitet, Institutionen för tillämpad fysik och elektronik.
    Recommendations for design of anchoring devices for bottom rails in partially anchored timber frame shear walls2010Ingår i: Proceedings of the 11th World Conference on Timber Engineering / [ed] Ario Ceccotti, 2010Konferensbidrag (Refereegranskat)
  • 17.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Relationship of the toughness and the modulus of elasticity in static bending of small clear spruce wood specimens2010Ingår i: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 68, nr 1, 109-111 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Unlike static bending, toughness is a mechanical property less commonly measured in clear wood. The paper presents results on the relationship of toughness and modulus of elasticity in static bending based on DIN standard tests on small, clear specimens of spruce, 2×2 cm2 in cross section.

  • 18.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Passialis, Costas
    Aristotle University, Greece.
    Voulgaridis, Elias
    Aristotle University, Greece.
    Ring width, latewood proportion and density relationships in black locust wood of different origins and clones2010Ingår i: IAWA Journal, ISSN 0928-1541, Vol. 31, nr 2, 169-178 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cross-sectional discs were cut at breast height from 19 black locust trees aged 18–39 years of different clones and origin (Greece, Bulgaria and Hungarian clones J, U and NY). Ring width, latewood proportion and dry density were measured according to standard laboratory techniques in order to examine their relationships. Latewood proportion was found to increase (except for one tree from Bulgaria) with increasing ring width and logarithmic equations were calculated with relatively high correlation coefficients. A positive relation between dry density and latewood proportion was found in black locust of Bulgarian origin and in the Hungarian clone NY while in all other cases no meaningful relationship was observed. In mature wood, improved positive linear correlations were observed between dry density and latewood proportion with the exception of the Hungarian clone U. Regression analysis revealed low correlations between dry density and ring width and only black locust from Bulgaria had a high positive correlation. The positive correlations between dry density and ring width were slightly improved in mature wood with the exception of clone J from Hungary.

  • 19.
    Hameed, Mahmood
    Damascus University, Syria.
    The Influence of Parafin emulsion on the physical- and mechanical Properties of Medium Density Fiber board (MDF) from Cotton Stems (Gossypium sp.) bonded with Urea formaldehyde    resin (UF).2010Ingår i: Damascus University Journal for the agricultural Science., Vol. 26, nr 2, 179-192 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This investigation has established the Possibility of improving the values of physical-(Water absorption and cross-swelling after 2, 24, and 48 hours) and mechanical Properties (binding strength and cross-tensile strength) of Medium Density Fiber board (MDF) from Cotton Stems (Gossypium sp.) bonded with Urea formaldehyde    resin (UF) by adding Parafin emulsion (0.5 % or 1 % to the dry weight of the fibers) when producing the Medium Density Fiber board (MDF) to reach the mean of values for the physical-(Water absorption and cross-swelling after 2, 24, and 48 hours) and mechanical Properties (binding strength and cross-tensile strength) of Medium Density Fiber board (MDF) in the European Standard.                                                           

  • 20.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Hellmich, Christian
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    The poroelastic role of water in cell walls of the hierarchical composite “softwood”2010Ingår i: Acta Mechanica, ISSN 0001-5970, E-ISSN 1619-6937, Vol. 217, nr 1, 75-100 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wood is an anisotropic, hierarchically organized material, and the question how the hierarchical organization governs the anisotropy of its mechanical properties (such as stiffness and strength) has kept researchers busy for decades. While the honeycomb structure of softwood or the chemical composition of the cell wall has been fairly well established, the mechanical role of the cell wall water is less understood. The question arises how its capability to carry compressive loads (but not tensile loads) and its pressurization state affect mechanical deformations of the hierarchical composite “wood”. By extending the framework of poro-micromechanics to more than two material phases, we here provide corresponding answers from a novel hierarchical set of matrix-inclusion problems with eigenstresses: (i) Biot tensors, expressing how much of the cell wall water-induced pore pressure is transferred to the boundary of an overall deformation-free representative volume element (RVE), and (ii) Biot moduli, expressing the porosity changes invoked by a pore pressure within such an RVE, are reported as functions of the material’s composition, in particular of its water content and its lumen space. At the level of softwood, where we transform a periodic homogenization scheme into an equivalent matrix-inclusion problem, all Biot tensor components are found to increase with decreasing lumen volume fraction. A further research finding concerns the strong anisotropy of the Biot tensor with respect to the water content: Transverse components increase with increasing water content, while the relationship “longitudinal Biot tensor component versus volume fraction of water within the wood cell wall” exhibits a maximum, representing a trade-off between pore pressure increase (increasing the longitudinal Biot tensor component, dominantly at low water content) and softening of the cell wall (reducing this component, dominantly at high water contents). Soft cell wall matrices reinforced with very stiff cellulose fibers may even result in negative longitudinal Biot tensor components. The aforementioned maximum effect is also noted for the Biot modulus.

  • 21.
    Boje, Lis
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Hannerz, Mats
    Löf, Magnus
    Southern Swedish Forest Research Centre, SLU.
    The role of internet in knowledge-building among private forest owners in Sweden2010Ingår i: Broadleaved forests in southern Sweden: Management for multiple goals / [ed] Magnus Löf, Jörg Brunet, Leif Mattsson, Mats Nylinder, Wiley-Blackwell, 2010, 225-234 s.Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    The major part of the temperate broadleaved forests in Sweden is owned by non-industrial private forest owners. The daily decisions on management of these forests therefore rely on a diverse owner population with various experience, age, education and attitudes. This study investigated how the forest owners obtain their information needed for their decisions. The use of internet as an information channel was specifically focused. Analyses were made of a postal questionnaire with responses from 327 private forest owners in southern Sweden. The respondents were sorted into groups of different age, education, gender, property size and residency (living on or off the property). For all groups, personal advisory was the most important channel for knowledge-building, followed by forest magazines and newsletters from forest organizations. Meetings and courses were also considered important, while internet had a lower rank. Still, 29% of all respondents considered internet as an important channel for knowledge-building in silviculture. Three-quarters of the respondents had internet access in their homes, and 40% used internet daily. Internet was used for forestry purposes at least monthly by 30% of the respondents. Age and education had a significant influence on the scored importance of internet as a communication channel for forest information, with younger forest owners (

    50 yr) and owners with a university degree being the most devoted internet users. Owners >65 yr and owners with only primary school education were much less inclined to rely on internet for their information needs.

     

  • 22.
    Petersson, Hans
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Use of optical and laser scanning techniques as tools for obtaining improved FE-input data for strength and shape stability analysis of wood and timber.2010Ingår i: V European Conference on Computational Mechanics, Paris, France, May 16-21, 2010,, 2010, Full paper, No 350, 10 pages- s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The paper assesses the potential of quality sorting of timber by use of modern scanning techniques, employing both fluorescent lighting and lighting from a large number of laser point sources. Tests were performed using wood-scanning equipment from one of its major manufactures. The results appear promising, especially in providing reasonably accurate predictions of grain-angle distributions on the wood surfaces, as well as rather accurate descriptions of knot locations and of fibre-angle disturbances around knots. A close characterization of end cross sections with respect to radial and tangential directions alike and of annual ring widths was also obtained. Characterization of the growth of annual rings in early to late wood was rather successful too. The techniques employed are illustrated by results of ongoing studies of both planed boards and of glued laminated beams.

  • 23.
    Eliasson, Lars
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Kifetew, Girma
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Volume yield and profit in the production of clear finger-jointed Scots pine (Pinus sylvestrisL.) boards2010Ingår i: European Journal of Wood and Wood Products, ISSN 0018-3768, Vol. 68, nr 2, 189-195 s.Artikel i tidskrift (Refereegranskat)
  • 24.
    Hameed, Mahmood
    Damascus University, Syria.
    Wood Science and Forest Products (Text-book)2010 (uppl. 2)Bok (Övrigt vetenskapligt)
    Abstract [ar]

     

    الفهرس

     

    مقدمة..................................................................................... 7

    الفصل الأول:

    نمو الشجرة وإنتاج الخشب

     Tree growth and production of woody tissue........................ 13

    الفصل الثاني:

    تمايز الخشب ، صفاته الظاهرية و التشريحية

    Lignifications of wood, macroscopic microscopic character of wood          27

    الفصل الثالث:

    بناء الأخشاب الطرية و القاسية

     Structure of soft- and heartwood....................................... 67

    الفصل الرابع:

    سلوك الخشب العصاري و الخشب القلبي تجاه المواد اللاصقة الصناعية

    The Behavior of sap- and heartwood towards synthetic Binder. 101

     

    الفصل الخامس:

    ديمومة  الخشب و المنتجات الخشبية و تدهورها

    Durability and deterioration of wood and wood products........ 153

     

     

    الفصل السادس:

    التربية والتنمية وجودة الخشب

    Silvicultural Practices and Wood quality.............................. 163

    الفصل السابع:

    المستخلصات الخشبية و منتجات الغابة

     Wood Extractives and Forest Products.............................. 175

    الفصل الثامن:

    الصناعات الخشبية

    Wood Industries............................................................ 217

     

    الفصل التاسع:

    تكنولوجيا صناعة الورق

    Paper manufacturing technology........................................ 263

     

    الفصل العاشر:

    الخشب و الفحم الخشبي باعتباره طاقة

    Wood and charcoal for Energy................................................. 289

     

    المراجع................................................................................ 297

    المصطلحات........................................................................... 311

     

    الجزء العملي.......................................................................... 331

     

  • 25.
    Hameed, Mahmood
    Damascus University, Syria.
    Wood Science and Forest Products (Work-book)2010 (uppl. 2)Bok (Övrigt vetenskapligt)
    Abstract [ar]

    الفهرس

     

    مقدمة................................................................................... 335

    مصطلحات علمية و تعاريف............................................................. 337

    الجلسة العملية الأولى:

    التعرف على خشب كل من المخروطيات وعريضات الأوراق....................... 347

    الجلسة العملية الثانية:

    كيفية التعرف على الأنواع الخشبية وتمييزها....................................... 349

    الجلسة العملية الثالثة:

    البناء الميكروسكوبي للخشب..................................................... 355

    الجلسة العملية الرابعة والخامسة:

    الخصائص الفيزيائية للخشب والمادة الخشبية المصنعة............................ 357

    الجلسة العملية السادسة والسابعة:

    الخصائص الميكانيكية للخشب والمادة الخشبية المصنعة.......................... 395

    الجلسة العملية الثامنة:

    الكشف عن عيوب الخشب ...................................................... 423

    الجلسة العملية التاسعة:

    تصنيف الأخشاب .............................................................. 425

    الجلسة العملية العاشرة:

    مشكلة إصدارات الفورم ألدهيد من المادة الخشبية المصنعة......................... 427

    الجلسة العملية الحادية عشرة:

    التعرف على أهم منتجات الغابة غير الخشبية..................................... 429

    الجلسة العملية الثانية عشرة:

    الصفات التكنولوجية لأهم الأنواع الخشبية المحلية و المدخلة في سورية............ 433

     

    الجلسة العملية الثالثة عشرة:

    أهم الأخشاب المصنعة........................................................... 453

    الجلسة العملية الرابعة عشرة:

    تكنولوجيا صناعة الورق.......................................................... 459

     

    ملحق :

            I-أهم الاختبارات الفيزيائية للفحم الخشبي........................................ 471

           II-أهم الاختبارات الفيزيائية للمواد اللاصقة....................................... 473

           III-أهم الاختبارات الكيميائية للخشب و المادة الخشبية المصنعة.................. 477

     

    المراجع :

    المراجع الألمانية......................................................................... 479

    المراجع الإنكليزية........................................................................ 481

    المراجع العربية........................................................................... 482

     

    المصطلحات...................................................................... 483-502

  • 26.
    Voulgaridis, Elias
    et al.
    Aristotle University of Thessaloniki, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    Adamopoulos, Stergios
    Technological Educational Institute of Larissa, Greece.
    ΑΝΑΓΝΩΡΙΣΗ ΞΥΛΙΝΩΝ ΕΥΡΗΜΑΤΩΝ ΑΠΟ TON ΤΑΦΙΚΟ ΤΥΜΒΟ ΤΗΣ ΜΙΚΡΗΣ ΔΟΞΙΠΑΡΑΣ-ΖΩΝΗΣ: Identification of the wooden finds from the Tumulus of Mikri Doxipara-Zoni2010Ingår i: ΑΛΟΓΑ ΚΑΙ ΑΜΑΞΕΣ ΣΤΟΝ ΑΡΧΑΙΟ ΚΟΣΜΟ: ΠΡΑΚΤΙΚΑ ΕΠΙΣΤΗΜΟΝΙΚΗΣ ΣΥΝΑΝΤΗΣΗΣ ΟΡΕΣΤΙΑΔΑ 30 ΣΕΠΤΕΜΒΡΙΟΥ 2006: Horses and Wagons in the Ancient World: Proceedings of One Day Scientific Meeting, Orestiada-Greece September 30, 2006 / [ed] Diamantis Triantafyllos, Domna Terzopoulou, Νομαρχία Έβρου , 2010, 151-173 s.Konferensbidrag (Övrigt vetenskapligt)
1 - 26 av 26
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