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  • 1.
    Aaby, Susanne
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. 1991.
    Carlsson, Henric
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Effektivisering av timmerplan på Kinnaredsågen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sågverken i Sverige letar kontinuerligt efter lösningar för att kunna effektivisera produktionen. I denna studie analyseras specifikt Derome Kinnareds sågens timmerplan. Genom en stopptidsanalys, undersökningar av nya tekniska lösningar, muntliga kommunikationer med personal samt arbetsledare och andra företag införskaffades underlag till analys. Åtgärder som kan utföras för att minimera produktionskostnaderna eller öka produktionen på timmerplan är att implementera ny teknik t.ex. fjärrmätning, digitalisera mätbesked med hjälp av SDC:s arkiv, omorganisera personalstyrkan samt införskaffa bemyndigad mätare. Förslagen indikerar att implementering av dem kan förbättra Kinnaredsågens ekonomi. Beroende på hur mycket företaget är villigt att investera kan det effektiviseras i olika grad. I samband med kommunikation med företagsrepresentanter kom man dock fram till att ny teknik kan vara bättre att implementera vid en nybyggnation.

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  • 2.
    Abrahamsson, Håkan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogstillståndet på ön Blå Jungfrun2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of the study was to investigate the forest in the national park on the Blue Maiden Island and compare with mainland forest data. The study was made in a quantitative way. The results from the field measurement were related to data from the Swedish National Forest Inventory.

    Oak, Scots pine and Lime were the most common tree species and constituted 47, 18 and 16 % of basal area, respectively, on the island.

    The mean heigt was 7 m and the volume of living trees was on average 72 m³/ha and dead wood 30 m³/ha. The average age at breast height was 137 years and the oldest tree was an oak with the age of 335 years at breast height. The amount of dead wood constituted 40 % of the total volume. Disturbances have had influence on the forest on the Island. To what extent cannot be determined without further investigations.

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  • 3.
    Abrahamsson, Max
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Challenges and opportunities for SMEs to adopt GHG calculation tools2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study is made to understand the opportunities and challenges SMEs have to adopt GHG calculation tools. Adoption of GHG calculation tools are common by large organizations and have proven as a consequence to lower their GHG emissions, motivate their employees and establish sustainability goals. Even thou a large amount of large organizations have adopted GHG calculation tools, this is very rare in SMEs. Using the theoretical framework called Rogers diffusion of innovation theory and a survey, the factors behind why or why not SMEs have adopted GHG calculation tools were studied. The results showed that only 9% of SMEs have adopted GHG calculation tools and the reason for this is lack of resources, competence and data. The analysis showed that the characteristics of an organization that affects this the most are leadership, education and regulations. In order to overcome the challenges, organizations should prioritize to have a leadership that motivates employees to engage in sustainability actions. Organizations should enable skill development in the field of sustainability to increase the competence. This would enable more organization to adopt GHG calculation tools and most likely lower their GHG emissions. 

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  • 4.
    Abu-Ragheef, Basil
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Polymer Aging Mechanics: An investigation on a Thermoset Polymer used in the Exterior Structure of a Heavy-duty Vehicle2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The use of plastic materials in the design of vehicle components is primarily driven by the need for vehicle weight and cost reduction. Additionally, these materials give design engineers freedom in creating appealing exterior designs. However, creating self-carrying exterior structures with polymers must fulfill long-term strength, creep and fatigue life requirements. Thus, the polymer polyDicyclopentadiene (pDCPD) has been chosen for this purpose. Its aging mechanics need to be understood by the design engineers to make the right decisions. This thesis has carried out mechanical tests such as uniaxial tensile testing, fatigue, and creep testing. Digital image correlation (DIC) system has been used to capture strain data from tensile tests. In the final analysis, DIC measurements proved more accurate than extensometer data retrieved from the testing machine. The rise in temperature has been captured using thermal imaging. Several degradation processes have been explored including physical aging, thermo-oxidation, photo-oxidation, chemical- and bio- degradations. Test results showed significant changes in mechanical properties after 17 years of aging. Additionally, severe thermal degradation has been observed in one of the tested panels of pDCPD. Temperature can rise to significant levels during cyclic loading at high stresses, which could have an impact on physical aging effects. Viscoelastic behavior has been explored and changes in dynamic and creep properties have been observed. The investigation also reviled that different defects caused by flawed manufacturing also can affect the material severely as one case has proved in this research.

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  • 5.
    Ackerfors, Viktoria
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vilken inställning har Länsstyrelserna till naturvårdsbränningar i områden med fornlämningar och övriga kulturhistoriska lämningar?2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Skogsbränderna har en stor betydelse för den biologiska mångfalden. Det brandpåverkade landskapet och dess dynamik skapar viktiga substrat och livsmiljöer för många pyrofila arter. På grund av att skogsbränderna har minskat i antal sedan 1800-talet, har kontrollerade naturvårdsbränningar utförts som ett komplement för dessa sedan 1980-talet. De kontrollerade naturvårdsbränningarna skapar de miljöer och substrat som många arter är beroende av. Eftersom tidigare mänsklig verksamhet satt prägel på skogarna återfinns idag ett stort antal fornlämningar och övriga kulturhistoriska lämningar i skogsmarkerna. Det är en utmaning att utföra naturvårdsbränningarna så att dessa lämningar inte skadas. Det råder också en brist på tydliga riktlinjer om hur Länsstyrelserna ska förhålla sig till naturvårdsbränningar i områden med lämningar. Denna studies syfte var att undersöka vilken inställning Länsstyrelserna har till naturvårdsbränningar i områden med fornlämningar eller övriga kulturhistoriska lämningar.

    Nyckelord: Naturvårdsbränningar, fornlämningar, övriga kulturhistoriska lämningar, Länsstyrelsen

    Keyword: Prescribed burnings, ancient remains, other cultural-historical remains, County Administrative Boards

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  • 6.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    A laser drilling technique to improve impregnability of spruce and fir2016In: 3rd BASF Wolman Conference, 14 September 2016, Linnaeus University, Växjö, Sweden, 2016Conference paper (Other (popular science, discussion, etc.))
  • 7.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Group of Forest Products2018In: Presented at Symposium "Perspectives in Renewables", 4-5 June 2018, BOKU Vienna, Austria, 2018Conference paper (Other academic)
  • 8.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Morphology, properties and recyclability of modified fibres and papers with different chemicals at laboratory, pilot plant and industrial trials2015Conference paper (Other (popular science, discussion, etc.))
  • 9.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Utilisation of renewable biomass and waste materials in furniture and construction composites2018Conference paper (Other academic)
  • 10.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Wood variation and properties for industrial use2018In: Presented at FRAS workshop “Varierat skogsbruk  - hur påverkar olika skötselstrategier framtidens träprodukter?", 2018Conference paper (Other (popular science, discussion, etc.))
  • 11.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Ahmed, Sheikh Ali
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Lankveld, Chiel
    Accsys Group, Netherlands.
    Acoustic properties of acetylated wood under different humid conditions and its relevance for musical instruments2018In: Proceedings of the 9th European Conference on Wood Modification 2018, Arnhem, The Netherlands / [ed] Jos Creemers, Thomas Houben, Bôke Tjeerdsma, Holger Militz and Brigitte Junge, The Netherlands: Practicum , 2018, p. 236-243Conference paper (Refereed)
    Abstract [en]

    In musical instrument making, less expensive wood species and materials with good characteristics and acoustical properties can provide potentials to find alternatives to the traditional exotic wood species used today. Modified wood could be such a choice if shows similar sound characteristics to wood coming from endangered and expensive tropical species with problematic commercial availability. In musical instruments, the overall functionality depends on the contribution of wood to different material performance indexes like sound radiation coefficient (R), characteristic impedance (z) and acoustic conversion efficiency (ACE). In this study, the performance indexes were measured for acetylated beech, maple and radiata pine and compared with these obtained for the reference wood materials maple, mahogany, alder and ash. A non-destructive free-free flexural vibration test method was used at constant temperature (20oC) but in different humid conditions- dry (35% RH), standard (65% RH) and wet (85% RH). Dimensional changes in the different humid conditions were also taken in account. Acetylated wood showed lower EMC with higher dimensional stability at each humidity level as compared with the reference wood materials. These properties are considered important factors for making quality musical instruments. Based on the acoustical properties, acetylated wood materials, especially radiata pine, showed good potential for use for musical instruments where specific characteristics of sound are required. However, the other types of acetylated wood can also be used for specific musical instruments.

  • 12.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Birmpilis, D
    Technological Educational Institute of Thessaly.
    Use and properties of recovered paper raw materials for the production of corrugated board2015In: Proceedings of the 14th International Conference on Environmental Science and Technology Rhodes, Greece, 3-5 September 2015, Global NEST , 2015Conference paper (Refereed)
    Abstract [en]

    The difficulty of predicting the properties of paper products produced from heterogeneous sources puts several limitations, which therefore lead to severe economic losses and only a comprehensive characterization will enable their better utilization. The project “RF-CORRUG –Quality control of raw materials from recovered fibres for the production of corrugated board”under the NationalStrategic Reference Framework 2007–2013 ARCHIMEDES IIIdeals with this common technical problem of the corrugated board industry. Specifically, the mainobjective of the project is to supportthe competitiveness of the corrugated board companies (mainly SMEs)by creatinga software tool based on practical models that can predict packaging grade paper properties from fibre data (qualitative, quantitative, morphological) used in their production. This paper presents information on the physical and mechanical properties of recovered packaging papers used in corrugated packaging. A number of different category papers (liners, flutings) used for corrugated board production in Greece were examined. The required paper properties included grammage, porosity, bursting strength, SCT, tensile strength and tearing resistance, and were measured by internationally recognized testersand standards. The data will be used to develop predictive models based on advanced statistical methods for the properties and performance of packagingaccording to information of their recovered raw paper materials.

  • 13.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Foti, Dafni
    Aristotle University of Thessaloniki, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Passialis, Costas
    Aristotle University of Thessaloniki, Greece.
    Manufacturing and properties of gypsum-based products with recovered wood and rubber materials2015In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 10, no 3, p. 5573-5585Article in journal (Refereed)
    Abstract [en]

    The experimental production of gypsum-based products (cylindrical samples, solid bricks) using different fractions of wood chips and rubber particles was studied. Recovered rubber and wood materials were mixed with gypsum and water in various proportions to fabricate gypsum-wood and gypsum-rubber cylindrical samples and standard solid bricks with six holes using appropriate molds. It was shown that to manufacture gypsum-wood and gypsum-rubber products with good mechanical strength, coarse fractions of wood and rubber should be used, but the proportion of wood or rubber should not exceed 25%. No thermal conductivity differences were found between the wood-and rubber-type of gypsum products, and particle size and material proportion had no effect. Samples with fine wood and rubber particles present at a lower proportion (25%) exhibited similar sound absorption behavior. The solid bricks had slightly higher strength when loaded at the large surface of their lateral upper side than when loaded at the small surface. The bricks provided better thermal insulation than both the extruded and pressed house bricks but lower than that of insulating bricks. The emission of volatile organic compounds out of the bricks was at an acceptable level according to regulations for construction products.

  • 14.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Karageorgos, Anthony
    Technological Educational Institute of Thessaly, Greece.
    Rapti, Elli
    Center for Research and Technology – Hellas (CERTH), Greece .
    Birbilis, Dimitris
    Technological Educational Institute of Thessaly, Greece.
    Predicting the Properties of Corrugated Base Papers Using Multiple Linear Regression and  Artificial Neural Networks2016In: Drewno, ISSN 1644-3985, Vol. 59, no 198, p. 61-72Article in journal (Refereed)
    Abstract [en]

    The difficulty in predicting the properties and behaviour of paper products produced using heterogeneous raw materials with high percentages of recovered fibres poses restrictions on their efficient and effective use as corrugated packaging materials. This work presents predictive models for the mechanical properties of corrugated base papers (liner and fluting-medium) from fibre and physical property data using multiple linear regression and artificial neural networks. The most significant results were obtained for the prediction of the tensile strength of liners in the cross direction from the origin (wood type, pulp method) of the fibres using linear regression, and the prediction of the compressive strength of fluting-medium in the longitudinal (machine) direction, according to the short-span test, using a neural network with one hidden layer with 6 neurons, with coefficients of determination at 95.14% and 99.28%, respectively

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  • 15.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Karastergiou, Sotirios
    Technological Educational Institute of Thessaly, Greece.
    Foti, Dafni
    Aristotle University, Greece.
    Filippou, Vasileios
    Aristotle University, Greece.
    ΑΝΑΚΤΗΣΗ ΞΥΛΟΤΕΜΑΧΙΔΙΩΝ ΑΠΟ ΑΠΟΣΥΡΟΜΕΝΕΣ ΜΟΡΙΟΠΛΑΚΕΣ ΜΕ ΥΔΡΟ-ΜΗΧΑΝΙΚΕΣ ΜΕΘΟΔΟΥΣ: [ Chips recovered from waste particleboards by hydro-mechanical methods ]2017In: ΠΡΑȀΤǿȀΑ : 18ου Πανελλήνιου Δασολογικού Συνεδρίου : “Η Ελληνική Δασοπονία μπροστά σε σημαντικές προκλήσεις: αειφορική διαχείριση δασών, δασικοί χάρτες, περιβαλλοντικές τεχνολογίες – δικτύωση και προστασία φυσικού περιβάλλοντος”: & International Workshop : “Information Technology, Sustainable Development, Scientific Network & Nature Protection” : 8-11 Οκτωβρίου 2017, ΕΔΕΣΣΑ ΠΕȁȁΑΣ, Περιοχή Βαρόσι, Hellenic Forestry Society , 2017, p. 349-356Conference paper (Refereed)
    Abstract [en]

    It was studied the recovery of wood chips from waste particleboards by immersion in water at ambient temperature and by mechanical treatment (agitation and impact, waterblasting). Four different categories of waste particleboards were used, with and without coating, after their reduction in smaller pieces with dimensions of about 7 × 8 cm.  The investigated methods were: (I) immersion for 3 days-impregnation with vacuum and pressure-agitation and impact (II) immersion for 7 days-drying-rewetting for 12 hours-agitation and impact (III) immersion for 3 days-waterblasting. The maximum thickness swelling (about 90%) was achieved by immersing the particleboards in the water for 3 days, and therefore the vacuum and pressure impregnation step can be omitted in practice. Recovery of wood chips was significantly higher (51.54%) in the case of successive wetting and drying cycles compared to simple immersion in water (17.32%). Both these methods I and II, involving agitation and impact for recovering wood chips from waste particleboards, are easily applicable at the industry. Method III with waterblasting resulted in complete recovery of wood chips within a very short time, but its application requires more research

  • 16.
    Adamopoulos, Stergios
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Säll, Harald
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sjöberg, Samuel
    Relationship between ultrasonic velocity and spiral grain in standing hybrid aspen trees2016In: Proceedings of the Hardwood Conference, Eco-efficient Resource Wood with Special Focus on Hardwoods, 8-9 September, 2016, Sopron, Sopron: University of West Hungary Press , 2016, p. 22-23Conference paper (Refereed)
  • 17.
    Adusei-Fosu, Kwasi
    et al.
    Scion, New Zealand.
    Rolando, Carol A.
    Scion, New Zealand.
    Richardson, Brian
    Scion, New Zealand.
    van Leeuwen, Rebecca
    Scion, New Zealand;Plant Protection Chemistry NZ Ltd, New Zealand.
    Gaskin, Robyn
    Plant Protection Chemistry NZ Ltd, New Zealand.
    Bader, Martin K.-F.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Auckland Univ Technol AUT, New Zealand.
    Pathan, Amin K.
    Minist Primary Ind, New Zealand.
    Evaluating the efficacy of potential fungicide-adjuvant combinations for control of myrtle rust in New Zealand2021In: Journal of Plant Diseases and Protection, ISSN 1861-3829, E-ISSN 1861-3837, Vol. 128, p. 1501-1515Article in journal (Refereed)
    Abstract [en]

    Myrtle rust is a serious fungal disease caused by Austropuccinia psidii affecting a number of Myrtaceae species in New Zealand and elsewhere. Control with fungicides or biologicals provides a mechanism to reduce the build-up of inoculum in the short-term while other strategies are being developed or deployed for long-term management. This study evaluated the efficacy of fungicides for control of myrtle rust under controlled conditions and identified adjuvants that would promote spreading of fungicidal active ingredients across the leaf surface. The spread of fungicide on detached M. excelsa leaves was assessed by applying three different adjuvants in combination with seven fungicides. Subsequently, M. excelsa plants were treated with three fungicides/mixes, (azoxystrobin + epoxiconazole, triademinol or a natural tea-extract) at a single rate followed by inoculation with A. psidii urediniospores on day 0, 7, 14 or 21 days after spraying. The response to infection in M. excelsa plants based on different inoculation timings at days 0, 7 and 21 significantly differed among fungicide treatments. The fungicide azoxystrobin + epoxiconazole was the most effective with infections significantly lower on the adaxial leaf surface than abaxial, despite good surface coverage of fungicide being achieved on both leaf surfaces. There were significant differences among fungicides based on the proportion of infected leaves on M. excelsa plants. Day 21 post-spray inoculation indicated a significant interaction between inoculation time and fungicide on leaf disease ratings. However, this was not the case at either 28 or 35 days post-inoculation. This research contributes to fungicide options for myrtle rust control in New Zealand.

  • 18.
    Agu, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vad tycker skogsägaren? En studie av kundnöjdhet2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med rapporten var att undersöka hur Mellanskog arbetar med kundnöjdhet och hur de skogsägare som anlitar dem för avverkningsuppdrag upplever kundnöjdheten. Resultatet från enkätundersökningen visade att de flesta som anlitat Mellanskog för ett avverkningsuppdrag visade en hög grad av kundnöjdhet. Mellanskog arbetade inte själv aktivt med analyser av kundnöjdhet eller hade ett uttalat arbetssätt kring kundnöjdhet.

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  • 19.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Acoustic properties of modified wood under different humid conditions and their relevance for musical instruments2018In: Applied Acoustics, ISSN 0003-682X, Vol. 140, p. 92-99Article in journal (Refereed)
    Abstract [en]

    In musical instrument making, there is a strong need to find alternatives to the traditional endangered and expensive tropical wood species used today. The present study examined whether different commercial and experimental modified wood materials have the necessary acoustic qualities under different humid conditions (dry, standard and wet) to contribute to the use of raw materials for wooden musical instruments. The materials were thermally-modified wood (ash, aspen and birch), acetylated wood (beech, maple and radiata pine), melamine- and phenol formaldehyde-treated beech and furfurylated Scots pine (Kebony Scots pine). Investigations involved physical (density ρ, Equilibrium moisture content EMC, volumetric shrinkage) and dynamic elastic testing by a free-free flexural vibration method to determine various acoustic characteristics: specific dynamic modulus (MOEdyn/ρ), damping coefficient (tanδ), speed of sound (c), specific acoustic impedance (z), sound radiation coefficient (R) and acoustic conversion efficiency (ACE). The modified materials and especially acetylated wood showed low EMC values and high dimensional stability at each humidity level, which are considered important factors for making quality musical instruments. Based on the obtained value ranges of all acoustical properties, the different modified wood materials could find uses in musical instruments where specific characteristics of sound are required. Furthermore, most of the modified materials showed an excellent acoustic performance in the three humid conditions based on a high ACE and low tanδ. Furfurylated Scots pine and phenol formaldehyde-treated beech showed an inferior acoustic quality with the lowest ACE and the highest tanδ, which is a less favourable combination for most of the musical instruments.

  • 20.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Swedish university of agricultural sciences, Sweden.
    Li, Junqiu
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kovacikova, Janka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Prediction of mechanical performance of acetylated MDF at different humid conditions2020In: Applied Sciences, E-ISSN 2076-3417, Vol. 10, no 23, p. 1-16, article id 8712Article in journal (Refereed)
    Abstract [en]

    Change of relative humidity (RH) in surrounding environment can greatly affect the physical and mechanical properties of wood-based panels. Commercially produced acetylated medium density fiberboard (MDF), Medite Tricoya®, was used in this study to predict strength and stiffness under varying humid conditions by separating samples in parallel (//) and perpendicular (⊥) to the sanding directions. Thickness swelling, static moduli of elasticity (MOEstat) and rupture (MORstat), and internal bond (IB) strength were measured at three different humid conditions, i.e., dry (35% RH), standard (65% RH) and wet (85% RH). Internal bond (IB) strength was also measured after accelerated aging test. A resonance method was used to determine dynamic modulus of elasticity (MOEdyn) at the aforementioned humid conditions. Linear regression and finite element (FE) analyses were used to predict the MDF’s static bending behavior. Results showed that dimensional stability, MOEstat, MORstat and IB strength decreased significantly with an increase in RH. No reduction of IB strength was observed after 426 h of accelerated aging test. A multiple regression model was established using MOEdyn and RH values to predict MOEstat and MORstat. In both directions (// and ⊥), highly significant relationships were observed. The predicted and the measured values of MOEstat and MORstat were satisfactorily related to each other, which indicated that the developed model can be effectively used for evaluating the strength and stiffness of Medite Tricoya® MDF samples at any humid condition. Percent errors of two different simulation techniques (standard and extended FE method) showed highly efficient way of simulating the MDF structures with low fidelity.

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  • 21.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Poggi, Francesco
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Walther, Thomas
    IKEA Industry AB, Sweden.
    Resonance and time-of-flight methods for evaluating the modulus of elasticity of particleboards at different humid conditions2020In: Wood research, ISSN 1336-4561, Vol. 65, no 3, p. 365-380Article in journal (Refereed)
    Abstract [en]

    Non-destructive testing of wood panels by either resonance or time-of-flight (TOF) methods provides possibilities for predicting their static bending properties. In the present study, three non-destructive devices (BING - Beam Identification by Non-destructive Grading by CIRAD, Montpellier, France, Fakopp Ultrasonic Timer and Sylvatest TRIO) were used for measuring the dynamic stiffness of different particleboard types. Fakopp Ultrasonic Timer and Sylvatest TRIO produce ultrasonic pulses to measure the sound velocity while BING uses resonance frequencies. Commercially produced particleboards with different thickness and densities were used to measure the dynamic modulus of elasticity (MOEdyn) in two directions (parallel and perpendicular to the production line) and at three different humidity levels (dry - 35%, standard - 65% and wet - 85% RH in constant temperature of 20°C ). MOEdyn of particleboards were correlated with the static moduli of elasticity (MOEstat) and rupture (MORstat). It was found that the non-destructive methods gave higher MOEdyn values in both production directions than that of MOEstat values. MOEdyn was found to decrease from dry to wet conditions. A very strong and statistically significant correlation existed between MOEdyn and static bending properties. MOEdyn correlated stronger to MOEstat than MORstat. At different humidity level, all three methods- Fakopp Ultrasonic Timer, BING and Sylvatest TRIO analyses showed good predicting capabilities to estimate MOEstat and MORstat of different particleboard types with high level of accuracy.

  • 22.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Michigan Technological University, USA.
    Adamopoulos, Stergios
    Swedish University of Agricultural Sciences, Sweden.
    Micro-Fibrillated Cellulose in Lignin–Phenol–Formaldehyde Adhesives for Plywood Production2023In: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 14, no 11, article id 2249Article in journal (Refereed)
    Abstract [en]

    Petrochemical-based phenol–formaldehyde (PF) adhesives are widely used in plywood production. To substitute phenol in the synthesis of PF adhesives, lignin can be added due to its structural similarity to phenol. Moreover, micro-fibrillated cellulose (MFC) can further enhance the bond performance, mechanical properties, and toughness of adhesive systems. Thus, the aim of this study was to evaluate the adhesion performance of lignin–PF (LPF) adhesives reinforced with MFC. In LPF formulations, three levels of MFC (0, 15, and 30 wt% based on the total solid content of adhesives) were added to the homogenous adhesive mixture. Three-layer plywood panels from birch (Betula pendula Roth.) veneers were assembled after hot pressing at 130 °C under two pressing durations, e.g., 60 and 75 s/mm. Tensile shear strength was measured at dry (20 °C and 65% RH) and wet conditions (water soaked at room temperature for 24 h). The results indicated that the addition of lignin reduced the strength of LPF adhesives in both dry and wet conditions compared to the control PF adhesive. However, MFC reinforcement enhanced the shear strength properties of the plywood. Furthermore, a longer pressing time of 75 s/mm slightly increased the shear strength.

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  • 23.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, The University Administration.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development.
    Brischke, Christian
    University of Goettingen, Germany.
    Adamopoulos, Stergios
    Swedish University of Agricultural Sciences, Sweden.
    Anatomical, Physical, Chemical, and Biological Durability Properties of Two Rattan Species of Different Diameter Classes2022In: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 13, no 1, article id 132Article in journal (Refereed)
    Abstract [en]

    Rattan cane is an important forest product with economic value. Its anatomical, physical, and biological properties vary with the cane height. This makes it difficult to select the appropriate cane diameter for harvesting. Understanding the material properties of rattan cane with different diameter sizes is important to enhance its utilization and performance for different end uses. Thus, the present study was performed on two rattan species, Calamus zollingeri and Calamus ornatus, at two different cane heights (bottom/mature and top/juvenile). Calamus zollingeri was studied at diameter classes of 20 mm and 30 mm, while Calamus ornatus was analyzed at a diameter class of 15 mm. The anatomical properties, basic density, volumetric swelling, dynamic moisture sorption, and biological durability of rattan samples were studied. The results showed that C. zollingeri with a 20 mm diameter exhibited the highest basic density, hydrophobicity, dimensional stability, and durability against mold and white-rot (Trametes versicolor) fungi. As confirmed by anatomical studies, this could be due to the higher vascular bundle frequency and longer thick-walled fibers that led to a denser structure than in the other categories. In addition, the lignin content might have a positive effect on the mass loss of different rattan canes caused by white-rot decay.

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  • 24.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Morén, Tom
    Luleå University of Technology.
    Sehlstedt-Persson, Margot
    Luleå University of Technology.
    Blom, Åsa
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Effect of oil impregnation on water repellency, dimensional stability and mold susceptibility of thermally-modified European aspen and downy birch wood2017In: Journal of Wood Science, ISSN 1435-0211, E-ISSN 1611-4663, Vol. 63, no 1, p. 74-82Article in journal (Refereed)
    Abstract [en]

    Conventional chemical wood preservatives have been banned or restricted in some applications due to human and animal toxicity and their adverse impact on the surrounding environment. New, low-environmental-impact wood treatments that still provide effective protection systems are needed to protect wood. Thermal modification of wood could reduce hygroscopicity, improve dimensional stability and enhance resistance to mold attack. The aim of this study was to investigate if these properties enhanced in thermally modified (TM) wood through treatments with oils. In this study, TM European aspen (Populus tremula) and downy birch (Betula pubescens) wood were impregnated with three different types of oil: water-miscible commercial Elit Träskydd (Beckers oil with propiconazole and 3-iodo-2-propynyl butylcarbamate, IPBC), a pine tar formulation and 100% tung oil. The properties of oil-impregnated wood investigated were water repellency, dimensional stability and mold susceptibility. The treated wood, especially with pine tar and tung oil, showed an increase in water repellency and dimensional stability. However, Beckers oil which contains biocides like propiconazole and IPBC showed better protection against mold compared with pine tar and tung oil. To enhance the dimensional stability of the wood, pine tar and tung oil can be used, but these oil treatments did not significantly improve mold resistance rather sometimes enhanced the mold growth, whereas a significant anti-mold effect was observed on Beckers oil treated samples.

  • 25.
    Aksoy, Samet
    et al.
    Istanbul Technical University, Türkiye.
    Hasan Al Shwayyat, Shouq Zuhter
    Marmara University, Türkiye.
    Nur Topgül, Şule
    Istanbul Technical University, Türkiye.
    Sertel, Elif
    Istanbul Technical University, Türkiye.
    Ünsalan, Cem
    Marmara University, Türkiye.
    Salo, Jari
    University of Helsinki, Finland.
    Holmström, Anton
    Katam Technologies, Sweden.
    Wallerman, Jörgen
    Swedish University of Agricultural Sciences, Sweden.
    Nilsson, Mats
    Swedish University of Agricultural Sciences, Sweden.
    Fransson, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Forest Biophysical Parameter Estimation via Machine Learning and Neural Network Approaches2023In: IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium: Pasadena, CA, USA, 2023, IEEE, 2023, p. 2661-2664Conference paper (Refereed)
    Abstract [en]

    This paper presents the first results of the ongoing development of new forest mapping methods for the Swedish national forest mapping case using Airborne Laser Scanning (ALS) data, utilizing the recent findings in machine learning (ML) and Artificial Intelligence (AI) techniques. We used Random Forest (RF) and eXtreme Gradient Boosting (XGBoost) as ML models. In addition, Neural networks (NN) based approaches were utilized in this study. ALS derived features were used to estimate the stem volume (V), above-ground biomass (AGB), basal area (B), tree height (H), stem diameter (D), and forest stand age (A). XGBoost ML algorithm outperformed RF 1 % to 3 % in the R² metric. NN model performed similar to ML model, however it is superior in the estimation of V, AGB, and B parameters.

  • 26.
    ALAGBADA, SAMUEL
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Comparative analysis of linear and circular manufacturing system paradigms for a steel-based product.: A case study of a mailbox manufacturing company2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The manufacturing industry has exerted a tremendous impact on the natural environment. The aim of this thesis is to evaluate the consequences of shift from linear manufacturing system to circular manufacturing system in order to decouple the environmental burden of production and consumption process in relation to quantity of carbon footprint, cumulative energy demand, natural resource consumption, waste generated and recovered presently.

    In response to this, life cycle assessment (LCA) is used to quantify and compare the associated environmental impact of the current manufacturing system of both Linear manufacturing system and the circular manufacturing system.

    The thesis therefore asserts that circular manufacturing system (CMS) is more sustainable compared to linear manufacturing system (LMS) in relation to its reduction capacity of the prevailing environmental indicators most especially global threat of natural resources depletion and climate change confronting biodiversity. The result shown that CMS seems more sustainable compared to LMS in relation to the studied environmental indicators.

    Further to this, the emerging circular manufacturing system, its transitional shift, challenges, and its relationships with other manufacturing dynamics for consideration are also highlighted and discussed. It was concluded that these prominent challenges are caused by organizational management in relation to leadership and communication (OLC), has the highest impact value. Similarly, the consequential effect was seen on the level of implementation of government policy (GPI) and deployment of state of the art design, knowledge and technology (DTK) for the paradigm shift. So, it is suggested that OLC should be given due consideration.

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  • 27. Alawode, Abiodun
    et al.
    Amiandamhen, Stephen
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Performance evaluation of a natural based adhesive derived from Irvingia kernel extracts on wood panel production2018In: 3rd International Conference on Composites, Biocomposites and Nanocomposites, Port Elizabeth, South Africa, 7th – 9th November 2018, 2018Conference paper (Refereed)
  • 28. Alawode, Abiodun
    et al.
    Amiandamhen, Stephen
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Properties and potential use of Irvingia gabonensis and Irvingia wombolu kernel extracts as an eco-friendly wood adhesive2019In: 73rd Forest Products Society International Convention, Atlanta, Georgia, USA, 25th – 28th June 2019, 2019Conference paper (Refereed)
  • 29.
    Algotsson, Elin
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Östman, Hanna
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Svensk contortatall (Pinus contorta) på en amerikansk marknad?2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Tack vare vissa önskade egenskaper gjordes en storsatsning på contortatall (Pinus contorta) i Sverige på 70-talet. Idag finns cirka 600 000 ha i Sverige som det gjorts provsågningar på och är nu dags att hitta användningsområden till. Syftet med denna studie var att undersöka skillnaden i utbyte mellan contortatall och gran (Picea abies) efter hyvling. Målet var att undersöka om sidobrädor av contortatall kan vara ett substitut till sidobrädor av gran vid hyvling ämnat för den amerikanska marknaden.Efter skanning av brädor samt manuell visuell sortering visade det sig att 92 % av granbrädorna var utan defekt medan 24 % av contortatallen var det. 34 % av contortatallen nedklassades för hål och 3 % av granen. Slutsatsen av studien visar att mängden och storleken på kvistarna är ett problem för contortatallvirket. För att få ett högkvalitativt virke behövs en djupare översyn av tillvägagångssättet för torkning och trädens tillväxtförhållanden.

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  • 30.
    Allert, Camilla
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Nilsson, Bengt
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Svensson, Anders
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Andersson, Ewa K
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Voluntary first responders’ experiences of being dispatched to suspected out-of-hospital cardiac arrest in rural areas: an interview study2024In: BMC Cardiovascular Disorders, E-ISSN 1471-2261Article in journal (Refereed)
    Abstract [en]

    Background: Out-of-hospital cardiac arrest (OHCA) is a leading cause of death, and survival outcomes vary across countries and regions. To improve survival, the European Resuscitation Council Guidelines encourage the implementation of technologies like smartphone applications to alert voluntary first responders (VFRs) who are near a suspected OHCA. VFRs are of great importance in the ´chain of survival´, but there is still a lack of knowledge about their experiences; especially of those operating in rural areas. Understanding those experiences is crucial in developing appropriate interventions to train, encourage, and safeguard VFRs in their mission. Therefore, the aim of this study was to describe VFRs´ experiences of being dispatched to suspected OHCA in rural areas.

    Methods: The study used an inductive design. The data were collected using individual interviews with 16 VFRs and analysed using qualitative content analysis.

    Results: The results are presented in terms of six generic categories ‘‘Being motivated and prepared’’, ‘‘Having strategies to undertake the mission’’, ‘‘Collaborating with others’’, ‘‘Being ethically aware’’, ‘‘Supporting the family members’’, and ‘‘Coping with the mission’’, which formed the basis of the main category ‘Desire to save lives and help others’. The findings showed that VFRs had a genuine desire to contribute to save lives in this rural area. Regardless of the circumstances, they were prepared to leave everything and act to the best for the victim and their family members. In theirs’ missions they collaborated with others at the scene and were guided by ethics while they acted in complex circumstances.

    Conclusions: VFRs dispatched in rural areas express a desire to save lives. In their missions, they acted in complex situations and experienced both emotional and ethical challenges.

    The design, implementation, and evaluation of support interventions directed at VFRs should be prioritised, especially in rural areas, as it can contribute to more people becoming and remaining VFRs, which in turn could contribute to sustainable development.

  • 31.
    Almeida, Juan Pablo
    et al.
    Lund University, Sweden.
    Rosenstock, Nicholas P.
    Lund University, Sweden.
    Forsmark, Benjamin
    Swedish University of Agricultural Sciences, Sweden.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Wallander, Håkan
    Lund University, Sweden.
    Ectomycorrhizal community composition and function in a spruce forest transitioning between nitrogen and phosphorus limitation2019In: Fungal ecology, ISSN 1754-5048, E-ISSN 1878-0083, Vol. 40, p. 20-31Article in journal (Refereed)
    Abstract [en]

    Nitrogen is the main limiting nutrient in boreal ecosystems, but studies in southwest Sweden suggest that certain forests approach phosphorus (P) limitation driven by nitrogen (N) deposition. We added N, P or N + P to a Norway spruce forest in this region, to push the system to N or P limitation. Tree growth and needle nutrient concentrations indicated that the trees are P limited. EMF biomass was reduced only by N + P additions. Soil EMF communities responded more strongly to P than to N. Addition of apatite to ingrowth meshbags altered EMF community composition and enhanced the abundance of Imleria badia in the control and N plots, but not when P was added. The ecological significance of this species is discussed. Effects on tree growth, needle chemistry, and EMF communities indicate a dynamic interaction between EMF fungi and the nutrient status of trees and soils. (C) 2018 Elsevier Ltd and British Mycological Society. All rights reserved.

  • 32.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Jacobsson, Martin
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. LNU.
    A computerised model to enhance the cost-effectiveness of production and maintenance dynamic decisions: A case study at Fiat2013In: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 19, no 2, p. 114-127Article in journal (Refereed)
    Abstract [en]

    Purpose:

    – To develop and test a model and software-based support system for better understanding

    of the interactions between man-machine-maintenance-economy (MMME), and enable cost-effective decisions.

    Design/methodology/approach:

    – The study is based on published knowledge and experience within maintenance, maintenance organization and production, and a case study.

    Findings:

    – Development of a model describing interactions between man-machine-maintenance-economy interactions and MMME software module. MMME test shows its ability to identify, quantify, assess and follow up losses in production time which is necessary when planning effective maintenance actions.

    Research limitations/implications:

    – In the paper the focus is to quantify production time losses in order to identify the root causes of the problem. The case study is performed at a manufacturing plant for truck engines.

    Practical implications:

    – A systematic approach of how to quantify and evaluate losses in production time in order to identify problems and problem areas within the production. This approach is discussed and motivated with the aim of achieving more cost-effective decisions in maintenance.

    Originality/value:

    – The model and software application developed enables a structured way of analyzing production time losses in order to find cost-effective solutions to the problems. The model is very flexible enabling it to be customized for a wide spectrum of branches.

     

  • 33.
    Altgen, Michael
    et al.
    Aalto Univ, Finland.
    Willems, Wim
    FirmoLin Technol BV, Netherlands.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Rautkari, Lauri
    Aalto Univ, Finland.
    Hydroxyl accessibility and dimensional changes of Scots pine sapwood affected by alterations in the cell wall ultrastructure during heattreatment2018In: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 152, p. 244-252Article in journal (Refereed)
    Abstract [en]

    There is a complex link between the water sorption behavior and the presence of accessible hydroxyl groups in the wood cell wall, which can be altered by heat-treatment (HT). This study analyses the effect of changes in the cell wall ultrastructure caused by two HT techniques on the hydroxyl accessibility, water vapor sorption and dimensional changes of Scots pine (Pinus sylvestris L.) sapwood. HT of wood in pressurized hot water at 120-170 °C was applied to cause the preferential bond cleavage, whereas HT of wood in oven-dry state in superheated steam at 180-240 °C was performed to create additional covalent cross-links within the cell wall matrix. Removal of cell wall polymers by HT and water leaching reduced the oven-dry dimensions of wood and enhanced the cellulose aggregation during drying. Cellulose aggregation restricted the cell wall shrinkage in circumferential direction, resulting in inhomogeneous shrinkage of the cell wall with only little changes in lumen volume by HT. Cellulose aggregation also reduced the water-saturated dimensions, but a decrease in swelling was only achieved when additional cross-links were formed by HT in dry state. Additional cross-links in the cell wall matrix also resulted in an additional reduction in water sorption at 25 °C and 93% RH. However, this was not caused by a further reduction in the hydroxyl accessibility. Instead, cross-linking was shown to reduce the amount of accessible OH groups that are simultaneously active in sorption, which was explained based on the concept of sorption of water dimers at hydroxyl group pairs at high RH levels.

  • 34.
    Alvskog, Kristina
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Rotstock av tall: Hur blir den framtida virkeskvaliteten?2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In Sweden the quality of Scots pine (Pinus sylvestris) saw timber has decreased. It is especially due to increased labour cost that has led to rational and effective forest management.

    This study investigated the quality of Scots pine and the potential to produce high quality stems in 9 stands in Bergslagen, Sweden. Two different stand types were investigated: Pruned stands and conventional managed stands. The outcome was a high percentage of valuable stems in the pruned stands (72-94 %), and 46-56 % in the conventional managed stands. It is possible to produce high quality timber of Scots pine with active management, for example by pruning and careful selection of stems in thinnings.

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  • 35.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Adamopoulos, Stergios
    Swedish University of Agricultural Sciences, Sweden.
    Adl-Zarrabi, Bijan
    Chalmers University of Technology, Sweden.
    Yin, Haiyan
    RISE, Sweden.
    Noren, Joakim
    RISE, Sweden.
    Recycling sawmilling wood chips, biomass combustion residues, and tyre fibres into cement-bonded composites: properties of composites and life cycle analysis2021In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 297, article id 123781Article in journal (Refereed)
    Abstract [en]

    This study investigated the properties and sustainability of cement-bonded composites containing industrial residues such as wood chips, tyre fibres and biomass combustion residues, i.e. bottom ash (BA) and fly ash (FA). The effect of cement-to-raw material (wood/tyre fibre) ratio (C/RM) and the aggregate content (BA and FA) on thermal and mechanical properties of the composites were investigated. Scanning electron microscopy (SEM) and life cycle analysis (LCA) were also conducted. The results revealed that as the aggregate content increased in wood composites, the mechanical properties also increased. The mean thermal conductivity and volumetric heat capacity of tyre composite samples were 0.37 W/mK and 1.2 MJ/m3K respectively, while the respective values for wood composite samples were 0.29 W/mK and 0.81 MJ/m3K. SEM analysis showed adequate bonding between wood/tyre fibres and cement matrix. LCA revealed that the materials share of the total primary energy use was about 60% for all analysed composites.

  • 36.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. University of Benin, Nigeria.
    Agwu, Chiedozie
    University of Benin, Nigeria.
    Ezenwaegbu, Pascal
    University of Benin, Nigeria.
    Evaluation of cement-bonded particleboards produced from mixed sawmill residues2021In: Journal of the Indian Academy of Wood Science, ISSN 0972-172X, Vol. 18, no 1, p. 14-19Article in journal (Refereed)
    Abstract [en]

    This study evaluates the application feasibility and properties of cement-bonded particleboards produced from mixed tropical hardwood species. Wood residues from a typical sawmill were collected, dried and used in the manufacturing of the cement composites. The wood residues used were from Ceiba pentandra and Gmelina arborea timber species. The residues were mixed in seven ratios in the production of the composite samples. Two control experimental samples containing unmixed residues of each species were also produced. The test carried out on the boards were flexural strength, water uptake properties and wet and dry screw withdrawal resistance. The effect of the wood mix ratio on the board properties was evaluated. The result showed that all properties except the screw withdrawal resistance were significantly influenced by the mix ratios (p < 0.05). The wet and dry screw withdrawal resistance ranged from 1170 to 1770 N and 1360 to 1830 N, respectively. The optimum wood mix ratio for enhancing mechanical performance of the boards was 1:4 of C. pentandra/G. arborea wood residues. Based on the result of this study, the particleboards produced can be used as wood composite ceiling tiles in building applications.

  • 37.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kumar, Anuj
    Natural Resources Institute Finland (Luke), Finland.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Jones, Dennis
    Luleå university of technology, Sweden;Czech university of life sciences Prague, Czech Republic.
    Nilsson, Bengt
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Bioenergy production and utilization in different sectors in Sweden: A state of the art review2020In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 15, no 4, p. 9834-9857Article in journal (Refereed)
    Abstract [en]

    In the continual desire to reduce the environmental footprints of human activities, research efforts to provide cleaner energy is increasingly becoming vital. The effect of climate change on present and future existence, sustainable processes, and utilizations of renewable resources have been active topics within international discourse. In order to reduce the greenhouse gases emissions from traditional materials and processes, there has been a shift to more environmental friendly alternatives. The conversion of biomass to bioenergy, including biofuels has been considered to contribute to the future of climate change mitigation, although there are concerns about carbon balance from forest utilization. Bioenergy accounts for more than one-third of all energy used in Sweden and biomass has provided about 60% of the fuel for district heating. Apart from heat and electricity supply, the transport sector, with about 30% of global energy use, has a significant role in a sustainable bioenergy system. This review presents the state of the art in the Swedish bioenergy sector based on literature and Swedish Energy Agency’s current statistics. The review also discusses the overall bioenergy production and utilization in different sectors in Sweden. The current potential, challenges, and environmental considerations of bioenergy production are also discussed

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  • 38.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Natural fibre modification and its influence on fibre-matrix interfacial properties in biocomposite materials2020In: Fibers And Polymers, ISSN 1229-9197, E-ISSN 1875-0052, Vol. 21, no 4, p. 677-689Article, review/survey (Refereed)
    Abstract [en]

    Biocomposite materials manufactured from natural fibres and polymer matrix represent a group of engineered composite products with diverse applications. These materials continue to find increasing applications due to their design flexibility, superior properties and aesthetic appeal. The applicability of these biocomposites, however, depends on theinteraction in the fibre-matrix interface. This paper reviews the state of the art research in fibre-matrix interfacial interaction based on published literature. A brief background on biocomposite materials is presented. The focus of this review is the modification of natural fibres and its effect on fibre-matrix interfacial adhesion and properties. In addition, the effect of chemical treatment on fibre composition and fibre-matrix interfacial bonding mechanism are discussed.

  • 39.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Stellenbosch University, South Africa.
    Meincken, Martina
    Stellenbosch University, South Africa.
    Tyhoda, Luvuyo
    Stellenbosch University, South Africa.
    Phosphate bonded natural fibre composites: a state of the art assessment2019In: SN Applied Sciences, ISSN 2523-3963, E-ISSN 2523-3971, Vol. 1, no 8, article id 910Article, review/survey (Refereed)
    Abstract [en]

    Over the last few decades, innovative wood composite products and processes have created markets for new and existing products. Inorganic bonded fibre composites have been developed for high performance applications using conventional cement and concrete. The demands for wood based composites along with increasing economic and environmental concerns on conventional wood products necessitate moving beyond the traditional processing methods to more cost-effective and environmentally friendly approaches. In the wake of the twenty-first century, a fast-setting phosphate binder with a low carbon footprint was developed, which can alternatively be utilized in wood composite development. This paper reviews the recent progress in phosphate bonded composite products, based on published literature from the last two decades. A brief background on Portland cement based natural fibre composites is presented. In addition, the mechanism of the formulation of phosphate binders, the effect of aggregates in the materials and the environmental benefits accruable to such materials are discussed.

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    Appl. Sci.
  • 40.
    Amiandamhen, Stephen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. University of Benin, Nigeria.
    Osadolor, Samson
    University of Tuscia, Italy;University of Benin, Nigeria.
    Recycled waste paper-cement composite panels reinforced with kenaf fibres: durability and mechanical properties2020In: Journal of Material Cycles and Waste Management, ISSN 1438-4957, E-ISSN 1611-8227, Vol. 22, no 5, p. 1492-1500Article in journal (Refereed)
    Abstract [en]

    There is a growing interest on recycling of waste fibres as an alternative to landfill disposal. The aim of the study was to investigate the durability and mechanical properties of waste paper-cement composite panels reinforced with varying kenaf fibre content (FC, 2-10%). The panels produced were evaluated for properties including modulus of rupture (MOR) and apparent modulus of elasticity (MOE). The resistance of the panels was tested in the field for both termite damage and fungi decay for a period of 24 weeks. Accelerated decay test was also performed on selected samples. The results showed that the mean MOR ranged from 3.17 MPa for samples with 10% FC to 4.84 MPa for samples with 8% FC. The mean MOE ranged from 248 MPa for samples with 10% FC to 1298.1 MPa for samples with 8% FC. Statistical analysis showed that the effect of the fibre content was significant on the properties evaluated (p<0.05). The study concluded that the optimum fibre content for improving strength and physical properties of paper-cement composites in a ratio of 1:1 (w/w) using kenaf as reinforcing fibre is 8%. The panels were highly resistant to both termite and fungi attack for the study duration.

  • 41.
    Andersson, Adrian
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Faktorer som bidragit till nyetablering av ädellövskog i Dalsland2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sett över hela landet växer ädellövskog endast på en procent av den produktiva skogsmarken. I det studerade området Dalsland utgörs virkesförrådet uppskattningsvis av tre procent ädla lövträd. Dess förekomst är därför att betrakta som relativt sällsynt. Denna studie hade för avsikt att intervjua markägare som har valt att nyetablera med ädellövskog och genom det förstå vad det är som bidragit till att de föryngrat med dessa trädslag.

    Undersökningen utfördes genom att sex individer som nyetablerat med ädellövskog intervjuades. Resultatet sammanställdes därefter genom att se på gruppen som en helhet och lyfta fram samtliga påverkande faktorer. Utifrån resultatet kunde 13 faktorer identifieras som bidragande och en förståelse kring dem redogöras för. 

    Det kan konstateras att ett flertal faktorer påverkat markägarna i valet att plantera ädellövskog.

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    Ädellövskogsbruk
  • 42.
    Andersson, Andreas
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hur noggrant skattar Katam DGV och GY jämfört med ALS?2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Skattning av skogliga variabler är inte längre begränsade till datainsamling genom manuell fältmätning. Numera kan skattningar göras genom insamling av data från såväl laserskanning (Airborne Laser Scanning, ALS) som mobilapplikationen Katam Forest (KF) som företaget Katam utvecklat. Dessutom kan varje enskilt träd skattas genom att kombinera Katam Treemap (KT), som använder sig av fotogrammetri för att mäta trädhöjd och identifiera träd, med KF (KF+KT) . I denna studie jämfördes skattningar av grundytevägd medeldiameter (DGV) och grundyta (GY) utförda med manuell fältmätning, ALS, KF samt KF+KT, i tre olika grandominerande bestånd. KF+KT beräknades felaktigt varför inga slutsatser kan dras om metoden. KF visade ett lägre relativt RMSE än ALS, 7,8 % jämfört med 9,6 % vid skattning av DGV. För GY var relativ RMSE 22,5 % vid KF, och 23 % vid ALS. KF bedöms med fördel kunna användas likvärdigt med manuell fältmätning.

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  • 43.
    Andersson, Anton
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Davidsson, Adrian
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hur mycket står risskotare stilla på grund av kommunikationsproblem?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The communicative interaction between contractor and subcontractor of residue forwarder plays a crucial role in the efficiency of handling forest residue. Since that type of work is at the end of the harvesting process, it may be that it is not as prioritized as the previous harvesting measures. The study investigates the communicative interaction between subcontractor that drives a residue forwarder and contractor and its connection to work-related production stops. The study was accomplished by a web-based survey and quantitative interviews conducted with eight selectively selected residue forwarder drivers in southern Sweden. The result of the survey showed that the average of all total production stops was one hour and 52 minutes under an average stop period of 25 working days. Most of the stops were caused by other work-related problems. Communication problems accounted for 20% of the number of production stops and the average stop duration was one hour and five minutes. The time when a residue forwarder was inactive seventeen minutes per day. In conclusion, the communicative problems are not the main reason to inactivity for residue forwarders. However, communication plays an important role in productive harvesting and represent the biggest possibility for improvement in the communication between residue forwarder drivers and contractor, which could lead to fewer production stops.  

     

    Residue Forwarders, Communication Problems, Production Stop and Forest residue. 

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  • 44.
    Andersson, Björn
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Utvärdering och utveckling av Fiskarhedens Trävaru AB:s traktdirektiv för slutavverkning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gross felling has accelerated in recent decades, and as a consequence, the requirements for forestry have increased. Today a comprehensive environmental consideration needs to be taken. This also imposes higher demands on the contractors. In order for contractors to be able to live up to the requirements, it is important that the customer of the service hands over a work instruction in connection to the removal of region assignments. This work instruction and work order is created in the form of a region directive. A qualitative region directive is considered important for Fiskarhedens Trävaru AB and for their contractors. A case study has been conducted to evaluate and describe the company's current region directive. The results show that the current region directive is sometimes inadequate due to that they are poorly completed. Important content is therefore not communicated as needed. A proposal of a new improved region directive, where the content is intended to be filled in better, has therefore been developed. With the help of this region directive, Fiskarheden can maintain sustainable forestry.

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  • 45.
    Andersson, Erik
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Noggrannhet och precision vid beståndsuppskattning av mobilapplikationen KATAM2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this essay was to evaluate the mobile application KATAM of accuracy, time, precision and practical use in comparison to volume estimation with data Digital Caliper and harvester report. The result of the diameter comparison showed similar estimates from KATAM and the Digital Caliper respectively. KATAM had a higher mean basel area, 7% and coarser mean diameter, 3.7%, compared to the Digital Caliper. KATAM also had overestimations in volume as compared to the harvesting report and the Digital Caliper concerning the mean stem, from 2.5% to 17.6%, depending on which sample areas were included and which version of KATAM was used. However, the basis of volume estimates was small and had error sources, which made the results of the measurements uncertain. Although the study shows an overestimation of the diameter, the mutual precision indicates that KATAM could be an alternative to the Digital Caliper when estimating the mean diameter.

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  • 46.
    Andersson, Frida
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kolkrediters påverkan på den enskilde skogsägarens ekonomi och kolsänkan i skogen2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Skogen spelar en viktig roll för att minska framtida klimatförändringar. Genom att enskilda skogsägare förlänger omloppstiden på skogsbestånd som uppnått lägsta slutavverkningsålder kommer skogen att bidra till att mer koldioxid binds upp. Detta scenario kan komma att hjälpa till så att Sverigesnår klimatmålet netto noll i koldioxidytsläpp till år 2045.Syftet med denna studie var därför att undersöka vilken ekonomiskt ersättning en enskild skogsägare kan få vid en förlängd omloppstid på 20 år men även om en förlängning av omloppstiden leder till att skogen blir en kolkälla i stället för att vara en aktiv kolsänka.Resultaten visade att vid högre ståndortsindex ökande och koldioxidinlagringen vilket genererade en högre subvention. Under den förlängda omloppstiden var skogen en aktiv kolsänka men att dess kapacitet att binda in koldioxid hade börjar minska. 

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  • 47.
    Andersson, Haidi
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. 1965.
    Hur upplevs estetik i skogsbruket?: How is aesthetics in forestry perceived?2016Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
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  • 48.
    Andersson, Helena W.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogsnäringens kompetensförsörjning: - en studie av hur nyutexaminerade studenters kompetens matchar näringens förväntningar2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Skogsnäringens kompetensförsörjning har beskrivits som en kritisk fråga för näringens fortsatta utveckling. Den skogliga utbildningens kvalitet, konkurrensförmåga och relevans för arbetsmarknadens krav är viktiga faktorer i rekryteringen av kompetenta personer till näringen. Det finns även ett uttalat behov av att öka attraktiviteten i såväl de skogliga utbildningarna som i de skogliga jobben. Detta examensarbete syftade till att studera matchningen mellan de nyutexaminerades kompetens och skogsnäringens förväntningar. En kvalitativ metod valdes för studien och semistrukturerade intervjuer genomfördes med nyanställda och med representanter från skogsnäringen. Resultatet pekar på förbättringsmöjligheter hos de skogliga utbildningarna med mer nischade utbildningsalternativ och praktiska tillämpningar som integreras i utbildningen, men också en tydligare definition av de olika yrkesrollerna inom skogsnäringen. Studien visar på ett behov av dialog och samverkan mellan akademi och skogsnäring. Men framför allt en gemensam syn hos medarbetare och ledning på vilken kompetens som krävs.

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  • 49.
    Andersson, Helena W.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Utvärdering av metoder för att mäta mental arbetsbelastning hos skotarförare - vid delautomatiserat och konventionellt kranarbete i simulatormiljö2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Forward operators are subjected to both physical and mental workload in their work and a way to reduce mental workload and increase productivity is to automating the crane movement. To enable study the impact of automation you need methods to estimate the forwarder operators mental workload in conventional crane work and with semi automation. This study evaluated the psychophysiological parameters; trapezius muscle activity, heart rate, heart rate variability, respiratory rate, skin conductance and finger temperature. To ensure the validity and methodology reliability one need to perform more extensive studies. As for future studies this work propose additional studies of forward operator mental workload in the simulator environment regarding heart rate, heart rate variability and respiration.

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  • 50.
    Andersson, Helena W.
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Rickardson, Anders
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Timmerkvalitet hos björk i blandskog med gran2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Birch is the dominant deciduous tree species in Sweden but only 16 % is found in pure birch stands. The majority of the birch (51 %) is to be found in conifer dominated stands. Swedish forest land comprises approximately of 23 % mixed stands and one problem is that for mixed stands there are few management recommendations. The underlying aim of this thesis was to study the management of mixed forest stands of spruce and birch to achieve good timber quality of birch. The study was based on a literature study and measurement in a field experiment launched in 1998 by the Swedish University of Agricultural Sciences (SLU). This study indicates that it is possible to achieve good timber quality of birch in mixed stands of birch and spruce. However, it requires that birch in mixed stands with spruce should be managed similar to management programs of pure birch stands.

     

    Keywords: Birch, spruce, timber quality, mixed stands.

     

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    Andersson H.W & Rickardson A.
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