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  • 201.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    The most cost-effective energy solution in renovating a multi-family house2019In: Cold Climate HVAC 2018, The 9th International Cold Climate Conference Sustainable new and renovated buildings in cold climates Kiruna – Sweden 12-15, March 2018 / [ed] Johansson, Dennis, Bagge, Hans, Wahlström, Åsa, Springer, 2019Conference paper (Refereed)
    Abstract [en]

    The Swedish government aims to reduce total energy demand per heated building area by 50% until 2050.  A large number of residential buildings, built within the so-called “Million homes program” in Sweden, need major renovations, which offers an opportunity to implement energy efficiency measures and thereby, reduce total energy demand. The best way to encourage the implementation of a major renovation is to demonstrate a practical method which reduces energy demand and provides economic benefits. Hence, this study aims to determine the most cost-effective energy solution in renovating a multi-family residential building. Multiple energy renovation measures were simulated on a case study to reduce the space heating and domestic hot water by 50%.  The case study building was built within the “Million homes program” and is located in Växjö, Swedish climate zone 3. Design Builder software was used for analysing the pre-renovation energy performance of the building. The renovation measures comprised different insulation thicknesses of external walls, attic and ground floors, windows with different U-values, a mechanical ventilation with heat recovery system, and solar system for supporting space heating and domestic hot water. Later, a multi-objective optimization was accomplished for analysing every possible combination of renovation measures.  The most cost-effective energy solution was obtained by calculating the net present value in a lifetime of 30 and 50 years and discount rate of 1%, 3% and 5%. Comparing the implications of two different lifetimes on net present value with implications of three different discount rates on net present value shows that lifetime has more influence on net present value. Furthermore, the results show the capability of the multi-objective optimization method in analysing multiple renovation solution.

  • 202.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Pardalis, Georgios
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Johansson, Jimmy
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Johansson, Peter
    Jönköping University.
    Application of multi-objective optimization for resolving conflicts when selecting windows2019In: The 9th International Conference on Sustainable Development in the Building and Environment(SuDBE2019)& the International Forum of Green and Healthy Buildings., Reading and Cambridge, UK, 2019Conference paper (Refereed)
    Abstract [en]

    Sweden passed legislation to achieve a target of net zero greenhouse gas emissions by the end of 2045. The Energy Performance of Building Directive further obliged European countries to ensure zero-energy building codes and improve the quality of indoor environments when buildings are renovated, as approximately 40% of total greenhouse gas emissions in Sweden are produced while heating buildings. Windows currently play a significant role in improving the quality of indoor environments and cutting total energy consumption, thereby reducing greenhouse gas emissions and mitigating environmental impact. Selecting a suitable window design is a complicated task compounded by two main difficulties: i) the availability of multiple window designs, each with a different glazing system, size, form and position; and ii) conflict between visual comfort, thermal comfort and energy consumption. Previous studies have primarily analysed a limited selection of window designs; however, analysing a wide variety of glazing systems, sizes, forms and positions will help resolve the abovementioned difficulties, thereby ensuring zero-energy building codes while improving the quality of an indoor environment. A multi-objective optimization was therefore completed to analyse the performance of a wide variety of window design variables and select suitable designs for an office room in Sweden. The results show the potential of multi-objective optimisation to resolve the difficulties of selecting suitable window designs.

  • 203.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Pardalis, Georgios
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Vadiee, Amir
    Mälardalen University, Sweden.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Profitability of various energy supply systems when renovating a single-family house in Sweden: case study2019In: International Conference on Applied Energy (ICAE 2019). August 12-15, Västerås, Sweden, 2019Conference paper (Refereed)
    Abstract [en]

    The majority of single-family houses in Sweden are affected by deteriorations in building envelopes as well as heating, ventilation and air conditioning systems, since they are about 30 years old. Theses house are therefore in need of extensive renovation, which provides an excellent opportunity to incorporate energy efficiency measures to reduce both the energy consumption and also operational. Although former studies analyzed the cost effectiveness of various renovation packages, they mainly excluded the evaluation of energy price implications on cost effectiveness of different renovation package in Sweden. Accordingly, this study considers three energy prices and quantifies the payback period (PBP) and internal rate of return (IRR) of the packages, when renovating a single-family house in Sweden. The renovation packages included three distinct energy supply systems, commonly installed when implementing energy renovations: ground source heat pump (GSHP), photovoltaic solar panels (PV), and an integrated GSHP and PV system. The analyses of results show that a the GSHP system provides higher IRR and the lowest PBP compared to the other two renovation packages, due to its high performance in reducing energy consumption and its relatively low investment cost. Furthermore, results show that raising the energy price can increase the IRR and reduce the PBP of the renovation packages and respectively. Moreover, increasing the interest rate adds on PBP of renovation packages, since it depreciates the cost for saved energy. 

  • 204.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vadiee, Amir
    Mälardalen University, Sweden.
    Johansson, Peter
    Jönköping University, Sweden.
    Achieving a trade‐off construction solution using BIM, an optimization algorithm, and a multi‐criteria decision‐making method2019In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 9, no 4, p. 1-14, article id 81Article in journal (Refereed)
    Abstract [en]

    The Energy Performance of Building Directive obligated all European countries to reduce the energy requirements of buildings while simultaneously improving indoor environment quality. Any such improvements not only enhance the health of the occupants and their productivity, but also provide further economic benefits at the national level. Accomplishing this task requires a method that allows building professionals to resolve conflicts between visual and thermal comfort, energy demands, and life‐cycle costs. To overcome these conflicts, this study exploits the incorporation of building information modelling (BIM), the design of experiments as an optimization algorithm, and the analytical hierarchy process (AHP) into a multi‐criteria decision‐ making method. Any such incorporation can (i) create constructive communication between building professionals, such as architects, engineers, and energy experts; (ii) allow the analysis of the performance of multiple construction solutions with respect to visual and thermal comfort, energy demand, and life‐cycle costs; and (iii) help to select a trade‐off solution, thereby making a suitable decision. Three types of energy‐efficient windows, and five types of ground floors, roofs, and external wall constructions were considered as optimization variables. The incorporation of several methods allowed the analysis of the performance of 375 construction solutions based on a combination of optimization variables, and helped to select a trade‐off solution. The results showed the strength of incorporation for analyzing big‐data through the intelligent use of BIM and a simulation in the field of the built environment, energy, and costs. However, when applying AHP, the results are strongly contingent on pairwise comparisons

  • 205.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vadiee, Amir
    Mälardalen University, Sweden.
    Johansson, Peter
    Jönköping University, Sweden.
    The profitability of various energy supply systems considering variations in future climate conditions2019In: International Conference on Applied Energy (ICAE 2019). August 12-15, Västerås, Sweden, 2019Conference paper (Refereed)
    Abstract [en]

    Ambitious targets were set in Sweden to increase the share of renewable energy resources and reduce greenhouse gas emissions. Renovating old detached houses can assist in achieving the abovementioned targets, since they make up a great share of the final energy consumption and carbon dioxide emissions in Sweden. Although, several attempts were taken to improve the energy performance of the detached houses, the implementation of energy efficient renovation is yet low due to mainly high investment cost. Former studies evaluated the cost effectiveness of various energy efficient renovations in renovating detached houses in Sweden, but they provided no information how possible climate futures affect the determination and adoption of energy efficiency policies, such as monetary instruments. Accordingly, this study considered three distinct energy renovation packages and analyzed the subsidies required for implementing renovation packages for given interest rates and lifetimes. Furthermore, three different climate scenarios were considered to analyze the effect of possible climate futures on subsidies required. The analyses of results show that increasing the lifetime have greater impact on required subsidies than increasing the interest rate. Furthermore, the results show that variation in future climate conditions changes the required subsidies when implementing energy efficiency renovations. Results can be used as an aid when adopting energy efficiency policies. 

  • 206.
    Jensen, Anna M.
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Löf, Magnus
    Swedish University of Agricultural Sciences.
    Effects of interspecific competition from surrounding vegetation on mortality, growth and stem development in young oaks (Quercus robur)2017In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 392, p. 176-183Article in journal (Refereed)
    Abstract [en]

    Facilitation by a neighboring woody understory has been suggested as a cost-effective and sustainable way to regenerate oaks. However, concerns about reduced plant growth and quality due to competing neighboring vegetation have hindered implementation. Here we studied competitive effects from herbaceous and woody vegetation on survival, growth, canopy development and stem quality in pedunculate oak (Quercus robur) in an open-field experiment in southern Sweden. Oaks were grown for eight years in four different competition treatments: no competing vegetation, with herbaceous vegetation (mainly grasses), with woody vegetation, and with both herbaceous and woody vegetation. During the first four years, competition had little effect on oak survival. However, after eight growing seasons, survival rates decreased to about 20% for oaks surrounded by woody vegetation, in contrast to oaks grown with only herbaceous vegetation that had a survival rate of near 100%. Competition from herbaceous and woody vegetation both reduced oak stem diameter and height growth, but they affected height growth differently. During the first growing seasons, oaks in the treatment with woody vegetation were able to keep up with the height growth of the surrounding vegetation. Thereafter, height growth stagnated, and after eight growing seasons heights of oaks in the treatment with woody competitors were only 30–39% that of oaks in the treatment without competing vegetation. In contrast, competition from herbaceous vegetation only restricted oak height development marginally. Interspecific competition not only restricted growth and survival but also shifted shoot architecture, resulting in a greater frequency of oaks with straight monopodial stems. Although competition from both herbaceous- and woody vegetation positively affected stem straightness, plots with woody vegetation had a greater proportion (0.42) of oaks with a single straight monopodial stem. Our results demonstrate that the facilitative competitive effects from herbaceous and woody vegetation could be used to control allocation patterns in young oaks, promoting development of tall straight monopodial stems. Considering the observed trade-off between high stem quality and survival, we recommend long-term assessment of this trade-off prior to application in practical forestry.

  • 207.
    Jensen, Anna M.
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Malmqvist, Cecilia
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Att mäta skog2019Book (Refereed)
  • 208.
    Jensen, Anna M.
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Oak Ridge National Laboratory, USA.
    Warren, Jeffrey M.
    Oak Ridge National Laboratory, USA.
    King, Anthony W.
    Oak Ridge National Laboratory, USA.
    Ricciuto,, Daniel M.
    Oak Ridge National Laboratory, USA.
    Hanson, Paul J.
    Oak Ridge National Laboratory, USA.
    Wullschleger, Stan D.
    Oak Ridge National Laboratory, USA.
    Simulated projections of boreal forest peatland ecosystem productivity are sensitive to observed seasonality in leaf physiology2019In: Tree Physiology, ISSN 0829-318X, E-ISSN 1758-4469, Vol. 39, no 4, p. 556-572Article in journal (Refereed)
    Abstract [en]

    We quantified seasonal CO2 assimilation capacities for seven dominant vascular species in a wet boreal forest peatland then applied data to a land surface model parametrized to the site (ELM-SPRUCE) to test if seasonality in photosynthetic parameters results in differences in simulated plant responses to elevated CO2 and temperature. We collected seasonal leaf-level gas exchange, nutrient content and stand allometric data from the field-layer community (i.e., Maianthemum trifolium (L.) Sloboda), understory shrubs (Rhododendron groenlandicum (Oeder) Kron and Judd, Chamaedaphne calyculata (L.) Moench., Kalmia polifolia Wangenh. and Vaccinium angustifolium Alton.) and overstory trees (Picea mariana (Mill.) B.S.P. and Larix laricina (Du Roi) K. Koch). We found significant interspecific seasonal differences in specific leaf area, nitrogen content (by area; Na) and photosynthetic parameters (i.e., maximum rates of Rubisco carboxylation (Vcmax25°C), electron transport (Jmax25°C) and dark respiration (Rd25°C)), but minimal correlation between foliar Na and Vcmax25°C, Jmax25°C or Rd25°C, which illustrates that nitrogen alone is not a good correlate for physiological processes such as Rubisco activity that can change seasonally in this system. ELM-SPRUCE was sensitive to the introduction of observed interspecific seasonality in Vcmax25°C, Jmax25°C and Rd25°C, leading to simulated enhancement of net primary production (NPP) using seasonally dynamic parameters as compared with use of static parameters. This pattern was particularly pronounced under simulations with higher temperature and elevated CO2, suggesting a key hypothesis to address with future empirical or observational studies as climate changes. Inclusion of species-specific seasonal photosynthetic parameters should improve estimates of boreal ecosystem-level NPP, especially if impacts of seasonal physiological ontogeny can be separated from seasonal thermal acclimation.

  • 209.
    Jiang, Wen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kumar, Anuj
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Natural Resources Institute Finland (Luke), Finland.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Liquefaction of lignocellulosic materials and its applications in wood adhesives — A review2018In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 124, p. 325-342Article in journal (Refereed)
    Abstract [en]

    Liquefaction, a useful method of turning whole biomass into liquids, provides advantages for energy andpolymers and finds applications in many sectors. This paper reviews the different liquefaction technologies andrecent advances in the development of sustainable wood adhesives. Current liquefaction technologies includehydrothermal liquefaction (HTL) and moderate acid-catalyzed liquefaction (MACL). HTL produces bio-oils asprimary products, and solid residues and gases as by-products. MACL depends on the solvent types used, whichare grouped to polyhydric alcohols and phenols. Bio-polyols from alcohol liquefaction, phenolated biomass fromphenol liquefaction and phenolic compounds rich-HTL bio-oils have been used in the production of liquefiedbiomass-based adhesives, which have shown competitive properties but face challenges for industrial uses. Yet, abetter understanding of reaction pathways and optimization of the liquefaction processes is needed.

  • 210.
    Joel, Gräsman
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Effekten av gödsling på björkars (Betula pendula) specifika bladarea (SLA) och tillväxt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The number one highest growth-limiting factor in Swedish forests is nitrogen, because of that fertilization often gives a significant growth increase, wherever you are in Sweden. Specific leaf area (SLA) can be used as a standard measurement of how much resources a tre has to use to build up light absorbing leaf area of needles/leaves. Since there is a strong linear relationship between tree growth and leaf area, there should also be a clear correlation between each leaf area of single trees and its diameter, basal area and volume growth (Xiao, 2005).The datamaterial for the study was collected at the forest estate, Toftaholm, near Ljungby in Kronoberg County (57 ° 0´N; 14 ° 3`E). Data were collected from birches growing in both in fertilized and unfertilized young stands of Birch during the growing season of 2018. The biomass sampling occured in May, July and August. At each occasion, samples were taken from 40 birches (a total of 120 samples were collected).The average value of SLA for all samples on the fertilized treatment was 17.33 m² / kg and 16.41 m² / kg for the non-fertilized treatment (Figure 4). The significance analysis obtained a p-value of 0.019 (Table 2), which confirms that there is a significant difference between the fertilized and the unfertilized treatment.In the significance analysis, it could be concluded that with a 95% probability, there is a significant difference between the comparison of all samples from the fertilized (G) and non-fertilized (OG) treatment.

  • 211.
    Johansson, Amanda
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Granvirkes permeabilitet beroende av dess fysikaliska utformning och applicerat färgsystem2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Densitetsmätningar och permeabilitetstest enligt EN 927-5 har utförts för att studera huruvida granvirkes fysikaliska egenskaper i kombination med applicerat färgsystem påverkar permeabiliteten. De egenskaper som studerats är frod- och senvuxenhet, splint- och kärnved samt densitet. Aktuella färgsystem som studerats är alkyd, akrylat och linolja, vilka jämförts med omålad referens. Studien påvisar inget samband mellan virkets densitet och permeabilitet, bestruket eller ej. Det som istället tycks påverka vattenabsorptionen är närvaro av splint-/kärnved samt frod-/senvuxenhet. Senvuxen kärnved var den bestrukna vedtyp som absorberade mest vatten gällande samtliga färgsystem. Vedtyp som hade lägst vattenabsorption varierade dock. Linolja var generellt det färgsystem som gav lägst permeabilitet, främst på frodvuxen kärnved. Denna kombination hade lägst absorption genom hela försöket.

  • 212.
    Johansson, Anders
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Olika markberedningsmetoders effekt på granplantors (Picea abies) överlevnad och höjdtillväxt vid Siljansfors försökspark2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Soil preparation is common when reforestation occurs after harvesting. Which method is chosen is governed by various factors such as soil moisture, humus layer thickness and depth of mineral soil. An experiment was made at SLU's experimental park in Siljansfors, about 20 km SW about Mora. The study comprises two different experimental areas, Sf 284 and Sf 287, where Picea abies was planted in 2004 and 2007 respectively. The soil is a moraine, the soil moisture class is fresh and the vegetation type is blueberry and lingonberry type. The site is located approximately 210 m above sea level. The purpose of this study was to evaluate and compare three different soil preparation methods regarding to survival and height growth of Picea abies during the first years after planting. In the case of planting without soil preparation and without chemically treated plants, the risk of a high mortality due to the damage caused by pine weevil (Hylobius abietis L.) is high during the first years. The soil preparation methods that were compared were mounding, patch scarification and the inverse method. These three methods were compared to each other as well as to no soil preparation at all. In the total aggregate plant material, half were chemically treated against pine weevil. The distribution of chemically treated and untreated plant material was evenly distributed throughout all trials and repeats. The study also included an evaluation of the so-called "edge effect", i.e. the effect of placing the plants closer than, respectively, longer than 10 cm from the edge of the scarified patch. In July 2009, plant height and survival were measured in the experimental areas. The result is presented as averages in the form of bar charts. The survival rate was increased by soil preparation, permetrin treatment and selection of planting point relative to humus edge. It was above all mounding and inverse soil preparation that favored the height of the plants.

  • 213.
    Johansson, Anna
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Trakhyggesbruk och hyggesfritt skogsbruk: En jämförelse av värderingar hos medlemmar i olika intresseorganisationer2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is a debate about clearcutting versus continuous-cover forestry in Sweden. In other studies forest owners and the general public have been seen to prefer different values. The aim of this study was to compare how members of various associations value clearcutting and continuous-cover forestry due to its effects on environmental-, social- and economical values. And also to understand the members motives for clearcutting and continuous-cover forestry, respectively. Through a web-based questionnaire this study found that members of all associations valued continuous cover forestry the highest, but members of Södra ranked clearcutting almost as high.  It was also found that Södra-members differed by favoring clearcutting, whilst members of Friluftsfrämjandet and Svenska Naturskyddsföreningen instead preferred continuous-cover forestry. Clearcutting had mostly economical motives and continous-cover forestry had mostly environmental- and social motives. This confirms former studies and points out a need for dialogues and exchange of knowledge when striving for sustainable development.

  • 214.
    Johansson, Ingvor Laila
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Tillväxt på gran och tall efter dikesrensning i Jönköpings län2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work was carried out for the Swedish Forest Agency as a follow-up on consultation for cleansing ditches in the district of Jönköping from autumn 2004 to 2009.The following things were studied: How was the consultation and results of cleansing perceived? How was the cleansing carried out? Has the forest responded to the cleansing through increased growth and if so how soon and how much? Has the ground flora changed? Were there any other positive or negative effects after the cleaning? Interviews were carried out with the property owners and the forest inventoried in the field.The work has been carried out in two stages, partly in the form of a market interview of 7 different properties and then as a field inviting with data collection. Based on the first visit, 10 stocks were selected for inventory of 4 properties, 2 pine (Pinus sylvestris) and 8 spruces (Picea abies) stands with a total of 136 trees, 27 pines and 109 spruces were measured. 122 trees were drilled for growth ring analysis 27 pines and 95 spruces. The drill cores were analyzed in WinDENDRO's growth ring program, summaries were made in Microsoft Excel and variance analysis was performed in SAS's statistical program.Trees that were closest to the ditch showed on average a higher radial growth after cleaning than before compared to trees that were farther from the ditch.6 out of 10 stands had after 4-7 years of cleansing still 20-50% bear- and white moss in the bottom layer. All landowners could see an improved profitability after cleaning and four out of seven could noticeably see better growth. Two had problems with troubling grass growth, but no one had seen any other positive or negative effects on the ground flora.

  • 215.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Blom, Åsa
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Dvinskikh, Sergey
    KTH Royal Institute of Technology.
    NMR-measurements for determination of local moisture content of coated wood2013In: JCT Research, ISSN 1547-0091, E-ISSN 2168-8028, Vol. 10, no 5, p. 601-607Article in journal (Refereed)
    Abstract [en]

    Local increased moisture content (MC) in wood constructions may result in different kinds of mechanical and, especially, biological degrading problems. Therefore, it is of great importance to control the MC of the material. However, there is at present no appropriate method for determining local MC in wood without destroying the product itself. Nondestructive measurements of local MC in wood is significant for the possibility of, for instance, monitoring the in situ MC in wood constructions over time, and thereby predicting potential problems. The nuclear magnetic resonance (NMR) technique has been shown to be valuable for the measurement of MC in wood. In this study, the possibility of utilizing this technique for local MC measurement in wood has been tested on wood samples exposed to water absorption for 72 h. The samples came from three different wood species treated with paint systems available on the market. In the wood samples an artificial “crack” had been created in the paint to introduce an area where the water could easily gain access to the wood. The results show the possibility of using the NMR technique for local MC measurements in wood. The measurement area, however, must be related to the properties of the material. In the case of wood, the measurement spot must be related to the early/latewood proportions. Further, a calibration of the NMR measurement must be made in relation to the expected density variations of the material.

  • 216.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Blomqvist, Lars
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nilson, Henrietta
    Linnaeus University, School of Business and Economics, Department of Organisation and Entrepreneurship.
    Landscheidt, Steffen
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Influencing factors to enable automation of wood furniture production2016In: Proceedings of the 12th meeting of the Northern European Networkfor Wood Science and Engineering (WSE): Wood science andengineering – a key factor on the transition to Bioeconomy / [ed] Bruno Andersons and Arnis Kokorevics, Riga, Latvia: Latvian State Institute of Wood Chemistry , 2016, p. 208-213Conference paper (Refereed)
    Abstract [en]

    The wood furniture industry in Sweden has an identified need of technological development in order to stay competitive. Especially the necessity to focus on automation has been identified. In the industry there are often needs to handle large levels of customization at the same time as keeping the production effective. This requires flexible automation solutions, often described as automated equipment that can rapidly be reconfigured for new products.Before automated applications are implemented in an industry there are issues to solve related to organisational, human and technological aspects. Based on this, the project - Flexible automation in manufacturing of laminated veneer products was initiated. The project is running since January 1, 2016 and is a two year national Swedish project. The aim of the project is to investigate challenges concerning automation in the wood furniture industry and especially focusing on bended laminated veneer products.In the project a case-study with the aim of identifying factors important for successful automation implementation in an involved wood manufacturing industry was performed. Key persons and staff of the company were asked to tell their life stories and a process mapping of the production was conducted.The results indicate a problematic relation between the management and the production staff, which partly can be referred to the shift from a family business to a private owned firm. Based on the process mapping, internal transport and handling are identified improvement areas. Productivity is disturbed by stops caused by processing residues and poorly defined materials. There is potential for improvement by adapting a process-oriented approach and defining the materials used.The case–study confirms the need to consider organizational and human aspects in production before initiating production. The study concludes the need to consider the special aspects of the wood material in production development.

  • 217.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Blomqvist, Lars
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sandberg, Dick
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Challenges using dielectric heating for THM processing of solid wood2013In: Evaluation, processing and predicting of THM treated wood behaviour by experimental and numerical methods / [ed] Carmen-Mihaela Popescu and Maria-Cristina Popescu, Iasi, Romania, 2013, p. 55-56Conference paper (Refereed)
  • 218.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sandberg, Dick
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Luleå University of Technology.
    Integrated use of product data for improved wood material utilization in the furniture and joinery production2013In: Pro Ligno, ISSN 1841-4737, E-ISSN 2069-7430, Vol. 9, no 4, p. 321-327Article in journal (Refereed)
    Abstract [en]

    Quality communication from customer to supplier is crucial for the effectiveness of a value chain. In the forest products industry, a mutual understanding of quality requirements between customer and supplier in relation to material characteristics and production conditions is important if the material is to be utilized effectively.

     

    In the mechanical wood industry, hardwood has normally been quality graded manually. This has been a work-intensive operation and a problematic working environment. Automatic grading equipment based mainly on camera and laser technology is therefore gradually replacing the manual grading operation which relies on the human eye. The cross-cutting of sawn wood into shorter components with well-defined quality parameters is a process which needs to be automated. This makes it possible for the sawmill to redefine the quality grading process with e.g. more complex grading rules. To gain full benefits from the new technology, however, the grading process must be redefined in cooperation with the customers. There is also an expressed need for tools to communicate the quality of products produced by sawmills.

     

    In this study, three case studies were therefore performed where the communication of requirements between sawmills and customers was studied with regard to three different components delivered from two sawmills. In one sawmill, two products were studied; one intended for a furniture producer and one for a joinery producer. In the other sawmill, the studied product was intended for a producer of solid wood panels. The idea has been to study the need for product information expressed by both the customer and supplier through the automatic grading process and to utilise this equipment for data collection and visualisation.

     

    The requirements for a communication and data exchange tool have been derived. There is often an expressed need to measure how different raw materials affect the volume yield in a process and how different quality requirements affect the volume yield. Sharing this information between customer and supplier has been shown to yield a mutual understanding of how and why deviations occur. Visualisation possibilities are a prerequisite for a mutual understanding of quality conceptions.

  • 219.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Schauerte, Tobias
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Lindblad, Fredrik
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Balancing the production flow in prefabrication of wooden houses2018In: Tools for sustainability, Forest Products Society, 2018Conference paper (Refereed)
    Abstract [en]

    The industrialization of wooden house building processes from traditional on-site production to off-site prefabrication is challenging, concerning the possibility of effective handling of numerous product variants, where each house is more or less unique. To obtain high productivity in the production, a well-balanced flow with minimization of waste is of great importance. In Sweden, many off-site house producers are in the starting phases of introducing advanced automation technologies in their production processes and the need for a more detailed process control therefore increases. In previous studies, the installation of windows has been identified as a demanding step in the prefabrication process, since it often creates a bottleneck i.e. the most overloaded part of process (Slack et al., 2016) and thus negatively affects the cycle-time and a balanced production flow.This study aims to understand, how the effectiveness of windows installations could be improved. By using a multiple case-study methodology, processes of several companies are compared and discussed. Further, suggestions for improvements are made for one case company. The results show that a replacement of the windows installation could (a) shorten the cycle-time of one wall by more than 10 %, (b) reduce the queueing time for the entire wall assembly process by more than 48 % and consequently (c) help to create a more balanced production flow.

  • 220.
    Johansson, Jimmy
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Woxblom, Lotta
    Sveriges lantbruksuniversitet.
    Prerequisites for the Realization of the Transnational Communication Platform WoodApps.2013In: Proceeding of ISCHP2013 - International Scientific Conference on Hardwood Processing, October 7-9, Florence, Italy., 2013Conference paper (Other academic)
  • 221.
    Johansson, Maria
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kopplingar mellan planteringskvalitet och plantors överlevnad hos SCA Skog, Ångermanland.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Using the right planting spots when planting can provide a lot of advantages forthe plant more nutrients, less competition and redused risk of damage from pineweevil. In this study comparisons have been made between quality follow upsfor not approved and approved plantings made by SCA in the distrikt ofÅngermanland. Few significant differences were found but not approvedplantings had more opportunitis for improvement than approved plantings. Moreplantings vere not approved on moist sites.

  • 222.
    Johansson, Marie
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Vessby, Johan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Blom, Åsa
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Olsson, Anders
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Expert competence for sustainable timber engineering: a master program in close cooperation between industry and academia2014In: WCTE 2014 - World Conference on Timber Engineering, Proceedings, 2014Conference paper (Refereed)
    Abstract [en]

    From a legislative point of view it has been possible to build timber buildings with arbitrary number of storeys in Sweden during almost two decades. Several buildings up to eight storeys have been completed during that time, but the competence for planning and building such structures are limited to a handful of actors. This fact has been recognized by funders of research/education and an educational program for spreading the knowledge within the industry led by Linnaeus University is financed since about two years. Particularly interesting in the programme is that the courses are developed in cooperation between the industry and the academia. The courses are to fulfil needs with respect to knowledge, but also with respect to format so that the main target group, skilled engineers within the industry, can find the motivation to follow a course or lager parts of the program.

  • 223.
    Johansson, Marie
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Säll, Harald
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Lundqvist, Sven-Olof
    Innventia.
    Properties of materials from Birch – Variations and relationships: Part 2. Mechanical and physical properties2013Report (Other academic)
    Abstract [en]

    Birch regarded as Sweden’s third largest tree species. The two birch species, Silver- and Downy birch represents about 12% of total Swedish timber volume. For forestry, birch an important tree species which today mainly used for the manufacture of pulp and paper.

    The aim of this project was to describe mechanical and physical properties of birch. The properties that have been studied are stiffness, bending strength, shrinkage, spiral gran angle, density and microfibril angle in the cell wall and vessel cells, from different parts of the birch stems grown at different rates. The mapped properties have been compared also with those of other tree species, mainly spruce. The long term aim is to increase the knowledge of the birch wood properties to provide better predict their impact on products as well as provide a basis for better utilization of Swedish birch raw material and hopefully using birch as future structural timber.

    Three birch stands with different growth was chosen: Two stands where the birch growth has been different in a mixed forests stand of spruce and pine, and a fast growing stand with improved birch seedlings. Samples were taken from four different heights in the trees. The main thing that has been analyzed is the bending strength, modulus of elasticity, shrinkage coefficients in different directions and spiral grain. The mechanical tests are carried out on tines that are 20 x 20 x 300 mm and the fiber angle measurements were carried out on discs. These results have supplemented by the results of analyzes conducted with lnnventias SilviScan instruments that are able to recognize variations of year ring wood properties. Some of these are density, and microfibril angle, which is also included in this report.

    The results show that the wood from normal growth and fast growth improved birch receive equivalent wood properties. The results also show that birch wood properties are slightly better than that in Norway spruce.

    The material in this project was limited to only three stands and 11 sampled trees and therefore it can´t provide complete answers to the birch trees different wood properties. Limitations include genetic origin, growth rate, earlier silvicultural treatment and number of sample trees.

  • 224.
    Johansson, Mattias
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Naturlig föryngring med frötallar empiriskt utfall gentemot teori: fältstudie från Norbergs kommun2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Föreliggande rapport studerar naturlig föryngring med frötallar. Syftet är att studera och förstå vilka faktorer som påverkar utfallet av naturlig föryngring med hjälp av fröträd genom att titta på rådande teoribildning på området samt jämföra denna med resultat från en egen genomförd fältstudie.

     

    Metodmässigt har studien genomförts som en fältstudie där två hyggen belägna i Norbergs kommun i Västmanland studerats ca 10 år slutavverkning.

     

    Slutsatserna, baserade på resultaten från fältstudien, visar att sammantaget har den naturliga föryngringen givit tillfredställande resultat, även om de olika inventeringsmetoderna ger något olika resultat. Vidare finner man att såväl läge, karaktäristika som ljusförhållanden, i enlighet med teorin, har en tydlig inverkan på föryngringsresultatet. Både provytans läge och karaktäristika på hygget samt skillnader mellan de två hyggena stödjer dessa resultat.

    Fältstudiens resultat ger vidare att det råder ett tydligt samband mellan god föryngringskvalitet och provytans närhet till frötallar.

    Avseende plantornas höjdfördelning konstateras att resultaten skiljer sig åt ganska markant dels mellan provytor samt speciellt mellan hyggena, vilket troligen kan sammankopplas med mer gynnsammare ljusförhållanden på det ena hygget. Vidare kan det skönjas att provytor med ett högt antal uppmätta plantor inte sällan också visade en hög höjd på plantorna.

    Resultaten gav även att inslaget av andra träslag än tall är stort på båda hyggena och står för mer än en tredjedel av antalet föryngrade plantor. 

  • 225.
    Johansson, Per Olof
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    En fallstudie av en gallringsfri skötselmetod för gran i Västra Götaland2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Results from three stands of Norway spruce in Vaestra Goetaland in Sweden. The age of the stands are 30, 50 and 50 years old. Each sample area was 100 m2. The stands have grown without any thinning and fertilizer. The maintenance method is called “Hyssnametoden”. The purpose of the study was to describe, follow-up and evaluate the impact of an alternative silvicultural method. The result shows that volume growth is higher than expected in this field.

  • 226.
    Jones, Grace
    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.
    Liziniewicz, Mateusz
    Swedish Forestry Research Institute, Sweden.
    Lindeberg, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Nondestructive wood density testing in downy birch and silver birch genetics field trial, southern Sweden2019In: 21st International Nondestructive Testing and Evaluation of Wood Symposium,: Freiburg, Germany, 2019 / [ed] Wang, Xiping; Sauter, Udo H.; Ross, Robert J.,, U.S. Department of Agriculture (USDA) , 2019, p. 79-86Conference paper (Refereed)
    Abstract [en]

    Non-destructive testing of wood density, as is already done for Eucalyptus, can allow for earlyselection of birch trees for breeding programmes and stands for harvesting. In this work, external stemquality traits were visually assessed in a family trial of downy (Betula pendula) and silver (B.pubescens) birch in southern Sweden. A subsample of trees was measured for wood density using thePilodyn resistometer portable NDT tool. An X-ray microdensitometric analysis of the subsample oftrees was completed using the Itrax X-ray machine for increment cores taken from the south face,through the pith to the north bark at 1.3 m stem height. The Pearson’s r value for Itrax density andPilodyn density was high (0.580 for downy birch and 0.795 for silver birch), and this correlationmeans Pilodyn should provide a good estimate of average birch wood density. Neither species hadstable wood density values at age 13 and both species’ density increased over time from pith to bark.Ring width influence on stem density was minor or non-existant, and may vary between birch species

  • 227.
    Jonsson, Björn
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vad motiverar skogsmaskinförare?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish forestry industry has since the beginning of the mechanization in the 1950´s had a technology development that streamlined the industry and reduced costs. The role of lumberjacks has changed a lot since hand tools were replaced by high-tech forestry machines. Previous studies indicate that the profession suffers from a poor working environment and poor organizational governance, in terms of lack work management, working hours and high demands and stress levels. This has led forest machine operators choosing to quit their jobs. The purpose of the study was to identify key factors that motivate forest machine operators and how their attitude is to monetary rewards. The survey was carried out as a survey study at the forest industry company SCA, where a questionnaire on motivation factors was sent to all forest machine operators. Swedish Cellulose is one of Sweden´s largest forest companies and Europe´s largest private forest owner. 48 machine operators responded to the questionnaire, the number of respondents to the whole brand was small, but a total survey for SCA. For a more generalizable result at brand level, more respondents had been desirable. Most of all work task and colleagues motivates the forest machine operators. Their motivation is disturbed by the lack of career opportunities and the lack of opportunities to influence decisions. The forest machine operators would get more motivation through more varied tasks and they think the most important thing about their work is to develop and become more professionally skilled. Performance-based monetary rewards motivate forest machine operators. Additional pay motivates them more than other forms of rewards, and they positively endorse the performance-based payroll system that exists at SCA today. Suggestions to needed measures to make forest machine operators motivated are more feedback from the leadership as well as involving the machine operators in decisions that are made. Communication between the leadership and machine operators needs to be improved to increase job satisfaction and maintain the motivation of employees. In order to increase their motivation, their work and duties need to vary more than they do today. What the responds consider would increase the variation in their work is unclear, and needs to be explored more closely.

  • 228.
    Jonsson, Cathrine
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Norrskogs distansskogsägare, deras upplevelse av nuvarande tjänsteutbud samt vilka tjänster de efterfrågar i framtiden2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Urbanization has reduced the population in rural areas while the urban population has increased in Sweden. As a consequence, also the number of distance forest owners increases continuously and today they own one third of Sweden's privately-owned forests. The purpose of this study was to describe the forest owner cooperative Norrskog’s distance forest owners, their perception of Norrskog's current services and their demand for services in the future. Data was collected through a web-based and a postal questionnaire. The results showed that the average age of Norrskog's distance forest owners was 63 years, a large proportion lived in metropolitan areas and a majority had more than 500 km to their forest property. Most of them owned their forest property together with relatives, 67 % were quite or very satisfied with their forest management, although most of them thought they had little knowledge of forest management. According to forest ownership, management of the family's land was valued the highest along with the feeling of ownership. Maximum yield and growth were valued the lowest.

    It was found that the forest owners in general were satisfied with the services offered by Norrskog. Thinning and precommercial cleaning got the highest average rating values and forest management plan and property valuation got the lowest. Among services for the future, - documentation of implemented silvicultural measures in the forestry plan was the most popular. Among Norrskog's distance forest owners many generational changes will likely occur soon. The new owners may be more interested in new ways of communication and services and therefore Norrskog should broaden its service portfolio to ease distance forest ownership.

  • 229.
    Jonsson, Jonas
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Höjdtillväxt, överlevnad och skador i praktiska etableringar av hybridaspbestånd i södra Norrland, anlagda 2004-20112015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Hybrid aspen is a crossbreed between European and North American aspen. It is a fast growing tree species that has shown strong growth in the South of Sweden. The follow-ups that have been made on hybrid aspen stands, have mainly been done on plant material in the South of Sweden. In the North of Sweden, only occasional studies have been made, and the knowledge of Northern hybrid aspen stands is, thus, unsatisfactory.

    In the South of Norrland, land owners have planted hybrid aspen, but what kind of plants it is, and how well these stands have established, is not ascertained, since data has not been compiled on the subject.

    The objective of this study is to evaluate practical plantations of hybrid aspen in the South of Norrland regarding height growth, survival and damages. The ambition is to increase the knowledge about practical plantations regarding height growth, survival and damages, and from the conclusions thereof, give recommendations for future establishments of hybrid aspen in the area.

    For the study, eight hybrid aspen stands in the South of Norrland were localised. Inventories were made of the stands, the land owners were interviewed and the material was compiled and analysed.

    Annual height growth varied amongst the stands between 0,4 and 1 meter and was in average 0,6 meter.

    Survival varied between 41 and 100 percent, with a mean value of 70 percent.

    The proportion of damaged stems varied between 0 and 85 percent, with a mean value of the stands of 27 percent.

    Plant mortality was explained by the land owners to be a result of field-mouse damages, which is confirmed by earlier research.

    The examined hybrid aspen stands in the South of Norrland demonstrate varying results in terms of height growth, survival and damages, but mainly a result that makes the tree species interesting as an alternative to traditional tree species.

  • 230.
    Jägervall, Filip
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Johansson, Bennie
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Efterfrågan av små skogsmaskiner vid gallring i södra Sverige2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Thinning with small forest machines is noticeably more expensive than thinning with normal sized forest machines. The demand for small machines is at present not researched, which means that the forest industry does not know at what extension the forest owners want to use small machines in thinning.

    The purpose of this study was to investigate south Swedish private forest owner’s demand of small machines in thinning.

    The study had both a quantitative and qualitative approach through a questionnaire and qualitative interviews. The questionnaire was sent to 500 forest owners.

    83 % of the respondents would choose/in some cases choose small machines in thinning if offered by a forest company.

    There was a relatively high demand (43 %) for small machines in first thinning in southern Sweden even if the felling cost increased with 45 SEK/ m³ solid volume excl. bark. With an increased felling cost over 45 SEK/ m³ solid volume excl. bark 21 % would choose small machines in first thinning.

  • 231.
    Karlsson, Eric
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sturesson, Brian
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Ett verktyg för sågoptimering av kubb2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta examensarbete har ett användarvänligt verktyg skapats för att möjliggöra undersökningar av värdeutfallet vid kubbsågning på VIDA Alvesta AB. Verktyget har skapats i Microsoft Excel som för många är en känd miljö. Just nu är det svårt att få lönsamhet inom sågverksbranschen. Råvaran är dyr och det tvingar sågverken att effektivisera sin produktion. Det här verktyget har vankantsandel som viktigaste variabel eftersom det maximerar värdeutbytet genom att använda maximalt tillåtna vankanter.

    En undersökning för produkten 47x100 har gjorts med avseende att dölja vankanter med hjälp av rundade hörn med radie 3 och 5 mm. Undersökningen visade att det går att dölja en större vankant genom att öka hörnradien från 3 till 5 mm. En ytterligare åtgärd som kan utföras för att utnyttja råvaran på ett bättre sätt är att minska på råmåtten. Om råmåttet minskas med 3 % kan en ekonomisk vinning erhållas.

  • 232.
    Karlsson, Josef
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Högläggning eller harvning: En jämförande studie av planteringspunkter och markpåverkan vid olika terrängförhållanden. 2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A comparing study of planting spots and terrain impact in different types of terrain.

  • 233.
    Karlsson, Ulrik
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    En jämförelse av antalet kvarvarande stammar mellan beståndsgående och stickvägsgående skördare i förstagallring2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In thinnings two types of machines, strip road and stand-thinning machines are used. The study's purpose was to see if there was any difference in the number of stems per ha after thinning with the various machine types. To find out whether there was any difference between the types of machines circular plots were used, 5,64 m, to count the stem number and basal area. The results showed differences in the number of stems per ha and also showed a difference in basal area. Stand-thinning machines creates conditions for stable stands since wide strip roads doesn`t occur.

  • 234.
    Keisu, Tanja
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Barrandel och fukthalt i färsk grot från gran i södra Sverige2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The forest is a renewable source of energy, enabling a reduction in dependence on fossil fuels. From a political point of view both climate impact as the dependence on imported energy from troubled parts of the world can be reduced by making use of forest fuel locally. In Sweden sawmill byproducts are fully exploited and therefore there is a potential to increase the proportion of forest fuels, particularly the removal of logging residues in form of branches and tops.

    Needles is a contentious issue in connection with the utilization of logging residues. The needles accounts for a small proportion of the biomass, but for a large part of the nutrients in a forest stand. Therefore, it is desirable that as much needles as possible is left in the harvesting area. If the needle proportion in fresh logging residues is known, it can also be used to calculate how much needles actually is left in the harvesting area. The energy converting industry does not want too much needles in the fuel, as it seems to create problems with combustion.

    The study is a field experiment conducted on 10 different harvesting areas in southern Sweden during March and April 2015. A pile of logging residues were loaded on a car trailer and then transported to Skogsbränsle Småland's chipper for decomposition. The test material was then processed at Linnaeus University, where needle and moisture content was determined.

    The results of this study conducted in the south of Sweden indicate that the average value of the needle content in fresh logging residues from spruce in southern Sweden is 22.2 %. The variation between different harvesting areas can vary greatly (17,5–32,4 %). This study showed a mean moisture content of fresh logging residues from spruce in southern Sweden of 38.7 %, which is lower than previous studies found. Softwood has the lowest moisture during early spring, during the implementation of this study, which may explain a relatively low moisture content which otherwise generally tend to be 50–55 %.

    This study found that the needle content in fresh logging residues from spruce in the south of Sweden is lower than the established range of 20–30 %. It has also been noted that there are large local variations in the needle content, therefore concluded that it is not right to adopt an overall value of the needle content. A general adoption of the needle content means e.g. that the assessment of how much needles left on the harvesting area becomes misleading. The needle content in fresh logging residues has a great impact on how much needles is left. Furthermore, this study found that the moisture content of logging residues from spruce is lower during early spring.

  • 235.
    Keskitalo, E. Carina H.
    et al.
    Umeå University.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Felton, Adam
    Swedish University of Agricultural Sciences.
    Björkman, Christer
    Swedish University of Agricultural Sciences.
    Berlin, Mats
    Uppsala Science Park.
    Axelsson, Petter
    Swedish University of Agricultural Sciences.
    Ring, Eva
    Uppsala Science Park.
    Agren, Anneli
    Swedish University of Agricultural Sciences.
    Roberge, Jean-Michel
    Swedish University of Agricultural Sciences.
    Klapwijk, Maartje J.
    Swedish University of Agricultural Sciences.
    Boberg, Johanna
    Swedish University of Agricultural Sciences.
    Adaptation to Climate Change in Swedish Forestry2016In: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 7, no 2, article id 28Article in journal (Refereed)
    Abstract [en]

    Adaptation to climate change in forestry has become a growing concern, in part due to the impact of storms and other events that have raised the awareness of such risks amongst forest owners. Sweden is one of Europe's most densely-forested countries, with this sector playing a major role economically. However adaptation has, to a large extent, been limited to the provision of recommendations to forest managers, most of which have only been partially implemented. This paper summarizes research with direct implications for adaptation to climate change within the forestry sector in Sweden. The focus is based in particular on providing examples of adaptations that illustrate the specific Swedish orientation to adaptation, in line with its relatively intensive forest management system. The paper thus illustrates a specific Swedish orientation to adaptation through active management, which can be contrasted with approaches to adaptation in other forestry systems, in particular those with limited management or management based on maintaining natural forests in particular.

  • 236.
    Klapwijk, M. J.
    et al.
    Swedish University of Agricultural Sciences.
    Boberg, J.
    Swedish University of Agricultural Sciences.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Bishop, K.
    Swedish University of Agricultural Sciences.
    Björkman, C.
    Swedish University of Agricultural Sciences.
    Ellison, D.
    Ellison Consulting, Switzerland.
    Felton, A.
    Swedish University of Agricultural Sciences.
    Lidskog, R.
    Örebro University.
    Lundmark, T.
    Swedish University of Agricultural Sciences.
    Keskitalo, E. C. H.
    Umeå University.
    Sonesson, J.
    Skogforsk, Uppsala.
    Nordin, A.
    Swedish University of Agricultural Sciences.
    Nordström, E-M
    Swedish University of Agricultural Sciences.
    Stenlid, J.
    Swedish University of Agricultural Sciences.
    Marald, E.
    Umeå University.
    Capturing complexity: Forests, decision-making and climate change mitigation action2018In: Global Environmental Change, ISSN 0959-3780, E-ISSN 1872-9495, Vol. 52, p. 238-247Article in journal (Refereed)
    Abstract [en]

    Managed forests can play an important role in climate change mitigation due to their capacity to sequester carbon. However, it has proven difficult to harness their full potential for climate change mitigation. Managed forests are often referred to as socio-ecological systems as the human dimension is an integral part of the system. When attempting to change systems that are influenced by factors such as collective knowledge, social organization, understanding of the situation and values represented in society, initial intentions often shift due to the complexity of political, social and scientific interactions. Currently, the scientific literature is dispersed over the different factors related to the socio-ecological system. To examine the level of dispersion and to obtain a holistic view, we review climate change mitigation in the context of Swedish forest research. We introduce a heuristic framework to understand decision-making connected to climate change mitigation. We apply our framework to two themes which span different dimensions in the socio-ecological system: carbon accounting and bioenergy. A key finding in the literature was the perception that current uncertainties regarding the reliability of different methods of carbon accounting inhibits international agreement on the use of forests for climate change mitigation. This feeds into a strategic obstacle affecting the willingness of individual countries to implement forest related carbon emission reduction policies. Decisions on the utilization of forests for bioenergy are impeded by a lack of knowledge regarding the resultant biophysical and social consequences. This interacts negatively with the development of institutional incentives regarding the production of bioenergy using forest products. Normative disagreement about acceptable forest use further affects these scientific discussions and therefore is an over-arching influence on decision-making. With our framework, we capture this complexity and make obstacles to decision-making more transparent to enable their more effective resolution. We have identified the main research areas concerned with the use of managed forest in climate change mitigation and the obstacles that are connected to decision making.

  • 237.
    Kroon, Johan
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Skogforsk, Sweden.
    Bergsten, Urban
    Swedish university of agricultural sciences, Sweden.
    Sonesson, Johan
    Skogforsk, Sweden.
    Increasing production value in Scots pine plantation through mixing with lodgepole pine2019In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 34, no 8, p. 689-698Article in journal (Refereed)
    Abstract [en]

    Mixing tree species could be a silviculture model that allows early harvest of short-rotation trees, while longer-rotation crop trees remain in the stand. We examined the effects on growth and tree characteristics in a planted experiment with lodgepole pine (LP) and elite-bred Scots pine (SP) in mixed (50/50) and monospecific plots in three different spacings (at 28 years of age after planting). The future development under different thinning regimes, including net present value for one rotation, was analyzed using the Heureka simulation software. As expected, LP had higher survival and initially more rapid growth than SP, with highest stand productivity and biomass production in LP monoculture during a rotation period as a result. However, intimate mixtures of SP and LP at the two widest spacings could give greater production and economic benefits, compared to SP in monoculture. It seems that elite-bred SP will differ in competitiveness against LP, depending on spacing for growth and some quality traits (branch and bark thickness, height of green crown). The findings support developing management systems for combining sparsely planted, and expensive, elite-bred SP in mixture with other trees that maintains high stem volume production and secures certain properties of trees and stands.

  • 238.
    Kuai, Le
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Parametrized Finite Element Simulation of Multi-Storey Timber Structures2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the acceleration of global urbanization trends, more and more intentions are put on multi-storey buildings. As the world leading area of wood construction, European countries started the construction of multi-storey timber building for a decade ago. However, unlike the traditional buildings made of reinforced concrete, the design of wooden high-rise timber buildings would face a substantial amount of new challenges because such high-rise timber buildings are touching the limitations of the timber engineering field. In this thesis, a parameterized three-dimensional FE-model (in ABAQUS) of a multi-storey timber frame building is created. Variable geometrical parameters, connection stiffness as well as boundary connections and applied wind and gravity loads are defined in a Python script to make it possible to analyze the influence of these parameters on the global structural behavior of the studied multi-storey timber frame building. The results and analysis implied that the script successfully worked and was capable to create different complex building geometries in an wasy way for the finite element analysis.

  • 239.
    Kumar, Anuj
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Czech Technical University in Prague, Czech Republic.
    Richter, Jan
    Czech Technical University in Prague, Czech Republic.
    Tywoniak, Jan
    Czech Technical University in Prague, Czech Republic.
    Hajek, Petr
    Czech Technical University in Prague, Czech Republic.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Šegedin, Urban
    University of Ljublijana, Slovenia.
    Marko, Petrič
    University of Ljublijana, Slovenia.
    Surface modification of Norway spruce wood by octadecyltrichlorosilane (OTS) nanosol by dipping and water vapour diffusion properties of the OTS-modified wood2018In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 72, no 1, p. 45-56Article in journal (Refereed)
    Abstract [en]

    The present research deals with a simple dipping method to insert octadecyltrichlorosilane (OTS) into cell walls of spruce wood and to deposit OTS layers on its inner and outer surfaces. Distribution and chemical interactions of OTS with wood polymers has been investigated by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. The OTS/n-hexane solution penetrated into wood via capillary forces through ray tracheids and bordered pits and was deposited as OTS organic-inorganic layers on wood cell walls. The hypothesis is supported by the results, according to which the OTS molecules are hydrolysed by the wood moisture and by free OH groups of the cell wall components. The hydrolysed OTS molecules react with the OH groups and elevate the hydrophobicity of wood.

  • 240.
    Kumar, Anuj
    et al.
    Natural Resources Institute Finland (Luke), Finland;Czech Technical University in Prague, Czech Republic.
    Ryparovà, Pavla
    Czech Technical University in Prague, Czech Republic.
    Kasal, Bohumil
    Wilhelm-Klauditz-Institut WKI, Germany.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hajek, Petr
    Czech Technical University in Prague, Czech Republic.
    Resistance of bamboo scrimber against white-rot and brown-rot fungi2020In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 15, no 1, p. 57-63Article in journal (Refereed)
    Abstract [en]

    Bamboo scrimber is one of the most emerging structural materials for future building applications andit possesses properties comparable to other natural wood-based engineered materials such as glulam,laminated veneer lumber and cross-laminated timber. The goal of this work was to study the decayresistance of bamboo scrimber against white-rot (Trametes versicolor) and brown-rot fungi (Serpulalacrymans). Bamboo scrimber samples were incubated in petri dishes with the wood-decaying fungiand the weight loss after 12 weeks was measured. The surface morphology of fungal-degradedbamboo scrimber was evaluated using optical microscopy. Based on the percentage weight loss,bamboo scrimber could be classified as highly resistant against bio-deterioration by white andbrown-rot fungi.

  • 241.
    Kumar, Anuj
    et al.
    Natural Resources Institute Finland (Luke), Finland.
    Ryparová, Pavla
    Czech Technical University in Prague, Czech Republic.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Prošek, Zdeněk
    Czech Technical University in Prague, Czech Republic.
    Žigone, Jure
    Czech Technical University in Prague, Czech Republic.
    Petrič, Marko
    University of Ljubljana, Slovenia.
    Hydrophobicity and resistance against microorganisms of heat and chemically crosslinked poly(vinyl alcohol) nanofibrous membranes2019In: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 360, p. 788-796Article in journal (Refereed)
    Abstract [en]

    Poly(vinyl alcohol) (PVA) is a water-soluble, semi-ionic and biocompatible polymer with excellent chemical and thermal stability. The chemical crosslinking of PVA membrane improve its stability towards humidity and water. In the present work, PVA nanofibrous membranes were fabricated using roller electrospinning techniques. The prepared membranes were crosslinked by heat treatment, glutaraldehyde dipping, and glutaraldehyde vapour. Furthermore, octadecyltrichlorosilane (OTS) treatment was used for hydrophobization of the crosslinked membranes. The prepared crosslinked membranes were analysed by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). The hydrophobization of PVA nanofibrous membranes were analysed by employing optical goniometer and auto-dynamic vapour sorption (AVS) techniques. Further, the PVA membranes were tested against algae and mould growth at in-vitro laboratory conditions. The SEM and FTIR results revealed significant differences in the morphology of the PVA nanofibrous membranes and in chemical bond formation due to crosslinking treatments. Water contact angle and AVS data confirmed a hydrophobization of PVA membranes by the treatments.

  • 242.
    Kumar, Anuj
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vlach, Tomáš
    Czech Technical University in Prague, Czech Republic.
    Ryparovà, Pavla
    Czech Technical University in Prague, Czech Republic.
    Sever Škapin, Andrijana
    Slovenian National Building and Civil Engineering Institute, Slovenia.
    Kovač, Janez
    Jožef Stefan Institute, Slovenia.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hajek, Petr
    Czech Technical University in Prague, Czech Republic.
    Petrič, Marko
    University of Ljubljana, Slovenia.
    Influence of liquefied wood polyol on the physical-mechanical and thermal properties of epoxy based polymer2017In: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 64, p. 207-216Article in journal (Refereed)
    Abstract [en]

    Epoxy resins are mostly produced from petroleum-based bisphenol A and epicholorhydrin. Bisphenol A is synthesized from non-renewable petroleum-based phenol and acetone. Biomass derived epoxy-based polymers (EBPs) are becoming the most promising alternative for petroleum-based counterparts, but still these biomass-based EBPs have inferior properties. In the present work, two types of epoxy resins were prepared with different weight percentages of resin (bisphenol A) and hardener. They were then modified with different weight percentages of liquefied wood from spruce sawdust. The derived EBPs were analysed in terms of tensile strength and tensile modulus, fractured surface morphology, thermal stability, long-term water adsorption and resistance to brown-rot fungus decay. The results revealed that the percentages of hardener and liquefied wood significantly influenced the overall properties of the EBPs.

  • 243.
    Kumarathunge, Dushan P.
    et al.
    Western Sydney University, Australia;Coconut Research Institute of Sri Lanka, Sri Lanka.
    Medlyn, Belinda E.
    Western Sydney University, Australia.
    Drake, John E.
    State University of New York, USA.
    Tjoelker, Mark G.
    Western Sydney University, Australia.
    Aspinwall, Michael J.
    University of North Florida, USA.
    Battaglia, Michael
    CSIRO Agriculture and Food, Australia.
    Cano, Francisco J.
    Western Sydney University, Australia.
    Carter, Kelsey R.
    Michigan Technological University, USA.
    Cavaleri, Molly A.
    Michigan Technological University, USA.
    Cernusak, Lucas A.
    James Cook University, Australia.
    Chambers, Jeffrey Q.
    University of California Berkeley, USA.
    Crous, Kristine Y.
    Western Sydney University, Australia.
    De Kauwe, Martin G.
    University of New South Wales, Australia.
    Dillaway, Dylan N.
    Unity College, USA.
    Dreyer, Erwin
    Université de Lorraine, France.
    Ellsworth, David S.
    Western Sydney University, Australia.
    Ghannoum, Oula
    Western Sydney University, Australia.
    Han, Qingmin
    Forestry and Forest Products Research Institute (FFPRI), Japan.
    Hikosaka, Kouki
    Tohoku University, Japan.
    Jensen, Anna M.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kelly, Jeff W. G.
    University of Washington, USA.
    Kruger, Eric L.
    University of Wisconsin‐Madison, USA.
    Mercado, Lina M.
    University of Exeter, UK;Centre for Ecology and Hydrology, UK.
    Onoda, Yusuke
    Kyoto University, Japan.
    Reich, Peter B.
    Western Sydney University, Australia.
    Rogers, Alistair
    Brookhaven National Laboratory, USA.
    Slot, Martijn
    Smithsonian Tropical Research Institute, Panama.
    Smith, Nicholas G.
    Texas Tech University, USA.
    Tarvainen, Lasse
    Swedish University of Agricultural Sciences, Sweden;University of Gothenburg, Sweden.
    Tissue, David T.
    Western Sydney University, USA.
    Togashi, Henrique F.
    Macquarie University, Australia.
    Tribuzy, Edgard S.
    Universidade Federal do Oeste do Pará (UFOPA), Brazil.
    Uddling, Johan
    University of Gothenburg, Sweden.
    Vårhammar, Angelica
    Western Sydney University, Australia.
    Wallin, Göran
    University of Gothenburg, Sweden.
    Warren, Jeffrey M.
    Oak Ridge National Laboratory, USA.
    Way, Danielle A.
    The University of Western Ontario, Canada;Duke University, USA.
    Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale2019In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 222, no 2, p. 768-784Article in journal (Refereed)
    Abstract [en]

    The temperature response of photosynthesis is one of the key factors determining predicted responses to warming in global vegetation models (GVMs). The response may vary geographically, owing to genetic adaptation to climate, and temporally, as a result of acclimation to changes in ambient temperature. Our goal was to develop a robust quantitative global model representing acclimation and adaptation of photosynthetic temperature responses.

    We quantified and modelled key mechanisms responsible for photosynthetic temperature acclimation and adaptation using a global dataset of photosynthetic CO2 response curves, including data from 141 C3 species from tropical rainforest to Arctic tundra. We separated temperature acclimation and adaptation processes by considering seasonal and common-garden datasets, respectively.

    The observed global variation in the temperature optimum of photosynthesis was primarily explained by biochemical limitations to photosynthesis, rather than stomatal conductance or respiration. We found acclimation to growth temperature to be a stronger driver of this variation than adaptation to temperature at climate of origin.

    We developed a summary model to represent photosynthetic temperature responses and showed that it predicted the observed global variation in optimal temperatures with high accuracy. This novel algorithm should enable improved prediction of the function of global ecosystems in a warming climate.

  • 244.
    Laisi, Andreas
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Varför somliga granar undgår angrepp av granbarkborren2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    After the storms Gudrun and Per, about 3 million cubic meters of standing forest were attacked. The cost of the both storms are estimated to have cost the Swedish forestry sector approximately 1.2 billion SEK. The study investigated why some of the spruces had survived the substantial attacks of the spruce bark beetles in Nyteboda forest nature reserve. Stem related variables and the environment the spruces grew in were investigated. Young trees with a high proportion of crown and a low diameter at breast height seem to avoid attacks to a greater extent. The environment they grow in, the microclimate also proved to be of great importance whether they are able to avoid attacks, as there were stems that had beneficial properties but still were attacked. 

  • 245.
    Landscheidt, Steffen
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Robotic Automation in Swedish Wood Product Industries2016In: Presented at Young Researchers Challenge - Marcus Wallenberg Prize, 10-13 October, 2016, Stockholm, Sweden, 2016Conference paper (Other academic)
  • 246.
    Landscheidt, Steffen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Automation Practices in Wood Product Industries: Lessons learned, current Practices and Future Perspectives2016In: The 7th Swedish Production Symposium SPS, 25-27 October, 2016, Lund, Sweden, Lund, Sweden: Lund University , 2016, , p. 9article id E1Conference paper (Refereed)
    Abstract [en]

    Wood product industries are a cornerstone of the Swedish industry and contribute vastly to the total Swedish export value. Wood as material itself has a promising perspective of becoming one of the most valuable resources. Sweden in particular has a long tradition and the knowledge of how to cultivate forests. In comparison to the highly automated forest industries, production systems of Swedish wood products industries are mostly characterized by a low degree of automation, tough manual labour and a relative low competency of the workforce. Facing fiercer competition on a global market, Swedish wood product industries are starting to lose touch with wood working industries in other industrialized European countries. Based upon established literature, this paper systematizes the status of automation practices in wood processing industries. The outcome of this study also outlines the expected effects and the future perspectives of digitalization and robotic automation for wood processing industries in high-1are not ready to implement the necessary standards to enter Industry 4.0. Not only are the technical prerequisites not fulfilled, but also a lack of appropriate production organization, logistics and economic basis is affecting negatively.

  • 247.
    Landscheidt, Steffen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Method for Assessing the Total Cost of Ownership of Industrial Robots2016In: 49th CIRP Conference on Manufacturing Systems, CIRP-CMS 2016, Commundo Tagungs Hotel Stuttgar,; Germany, 25 May 2016 through 27 May 2016 / [ed] Bauernhansl T.,Westkamper E., Elsevier, 2016, Vol. 57, p. 746-751Conference paper (Refereed)
    Abstract [en]

    With the launch of Industry 4.0, automation has increasingly been put into focus as one of the key factors for future production. The introduction of industrial robots is widely seen as an effective strategy against rising competition and outsourcing to low-cost countries. The investment into industrial robot cells is often based on the initial offering and its pay-off time. However, procurement decisions based only on the initial price are often poor decisions since they do not consider hidden cost factors such as maintenance or energy consumption. Evaluating the total cost of ownership (TCO) of industrial robots is a far better alternative to calculate all costs involved during their company ownership. Thus far, only a few models concerning TCO or similar cost analysis techniques for industrial robots have been published and empirical studies of the economic aspects of robotic implementation are scarce. The key contribution of this paper is the development of a conceptual model for TCO calculation of industrial robots, which can be used during the decision making process. The developed model was tested in two case studies, one for material handling robots and one for arc welding. The goal was to identify the most crucial factors allowing an easily estimated calculation of the TCO based on the net present value. As most contributing factors, operators’ wages, spare parts and energy consumption are identified. However, this paper also shows that retrieving necessary data from companies turned out to be complicated, because of the low awareness of these companies’ expenditures for the costs generated by their automation equipment. In accordance with the results, both, a simple template was created in order to support the people involved in the decision making process with additional investment information and crucial factors are pointed out for measuring and evaluation in of future digitalized robot systems.

  • 248.
    Landscheidt, Steffen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Winroth, Mats
    Chalmers University of Technology.
    Differences on automation practices in wooden single-family houses manufacturing: Four case studies2017In: 23rd International Wood Machining Seminar Proceedings / [ed] Marcin Zbiec and Kazimierz Orlowski, Warsaw, Poland: Warsaw University of Life Sciences , 2017, p. 350-359Conference paper (Refereed)
    Abstract [en]

    In densely forested countries, forest and wood-based products are an important contributing factor to the country’s economy and also a valuable resource for house manufacturing. With rising demand for housing in Europe, wooden houses have become more of an alternative to concrete houses. Although wooden houses have always been popular in Nordic countries, higher demand puts more pressure on seemingly outdated production facilities and personnel in order to supply the market. Whereas many other industries strive to modern production concepts such as Industry 4.0 to adapt to new market conditions, industrial timber house building is still characterized by a high amount of manual labor.

    In Europe´s highly industrialized countries, labor costs influence wooden house manufacturers rather negatively and exert great pressure on them to stay competitive. Some companies have chosen outsourcing of their operations and production as means to survive. Another way, already successfully proven in other industries, is the automation and digitalization of production processes. Effective implementation of automation equipment depends on several factors, e.g. production volume, applied material, chosen application or cycle times. It is not entirely clear which factors are contributing to the successful change to a more automated production.

    Based on an Industry 4.0 readiness model, the purpose of this study is to seek out which dimensions correlate with each other in order to support improved production processes and efficiency for wooden single-house manufactures. 

    By applying a comparative case study approach, automation standards and practices in Sweden, Germany and Austria, are described and compared. Results of this case study reveal that a production strategy together with sound digital support and information sharing leads to the best production systems for single-wooden houses manufacturers.

  • 249.
    Landscheidt, Steffen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Winroth, Mats
    Chalmers University of Technology.
    Opportunities for robotic automation in wood product industries: The supplier and system integrators' perspective2017In: 27th International Conference on Flexible Automation and Intelligent Manufacturing, FAIM2017 / [ed] Pellicciari, M; Peruzzini, M, Elsevier, 2017, p. 233-240Conference paper (Refereed)
    Abstract [en]

    In this study, the opportunities for automation in the poorly automated wood product industry are highlighted. This isaccomplished by conducting a qualitative interview study of suppliers and system integrators for industrial robots active in thisparticular industry sector. Five case companies are chosen in order to explore the unique dimensions responsible for successfulautomation implantation in wood product companies. Results show that a low understanding of automation opportunities, unclearrequirements specifications, and small production volumes are the main problems for suitable automation solutions. Althoughwood is a fragile and changeable material, existing technology allows its manipulation with industrial robots.

  • 250.
    Landscheidt, Steffen
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Winroth, Mats
    Chalmers University of Technology.
    Wester, Hans
    Yaskawa Nordic AB.
    The future of industrial robot business: Product or performance based?2018In: Proceedings of the 8th Swedish Production Symposium (SPS 2018) / [ed] Mauro Onori, Lihui Wang, Xi Vincent Wang, Wei Ji, Elsevier, 2018, Vol. 25, p. 495-502Conference paper (Refereed)
    Abstract [en]

    The robot market today is mainly based on product-centered sales concepts. In the future, traditional procurement of industrial robots can be expected to become less important and the business models will shift the focus towards leasing or even pay-per-use. This paper discusses how these new business models should be designed and what components and features are needed for successful implementation. Digitalization, circular economy, cultural barriers, business traditions and fear of new philosophies are investigated and put into the context of the advantages offered. A possible transformation process is set into the context of the product-process matrix.

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