In this paper, a portable scanner to determine the 3D shape of logs was evaluated and compared with the measurement result of a computer tomography scanner. Focus was on the accuracy of the shape geometry representation. The objective is to find a feasible method to use for future data collection in Mozambique in order to build up a database of logs of tropical species for sawing simulations. The method chosen here was a 3D phase-shift laser scanner. Two logs, a birch log with bark and a Scots pine log without bark, were scanned, resulting in 450 cross sectional “images” of the pine log and 300 of the birch log. The areas of each point cloud cross section were calculated and compared to that of the corresponding computer tomography cross section. The average area difference between the two methods was 2.23% and 3.73%, with standard deviations of 1.54 and 0.91, for the Scots pine and birch logs, respectively. The differences in results between the two logs are discussed and had mainly to do with presence of bark and mantle surface evenness. Results show that the shape measurements derived from these methods were well correlated, which indicates the applicability of a 3D phase-shift laser scanning technology for gathering log data.

Approximately, 13.5 % of the standing volume of productive forest land in Sweden is covered by birch and aspen, which provides the vast potential to produce value-added products such as densified wood. This study shows whether it is possible to densify those species with a thermo-hygro-mechanical (THM) process using heat, steam, and pressure. In this process, transverse compression on thin European aspen (Populus tremula) and downy birch (Betula pubescens) boards was performed at 200 ºC with a maximum steam pressure of 550 kPa. To obtain a theoretical 50 % compression set, the press’s maximum hydraulic pressure ranged from 1.5 to 7.3 MPa. Preliminary tests showed that ~75 % of the birch boards produced defects (blisters/blows) while only 25 % of the aspen boards did. Mainly, radial delamination associated with internal checks in intrawall and transwall fractures caused small cracks (termed blisters) while blows are characterized by relatively larger areas of delamination visible as a bumpy surface on the panel. Anatomical investigations revealed that birch was more prone to those defects than aspen. However, those defects could be minimized by increasing the pre-treatment time during the THM processing.

The biggest threats to the longevity of a timber bridge are rot and decay. Wood protection by design, inspections, and monitoring of the bridge for elevated moisture content will ensure that the full service life of the structure can be achieved. Today's sensors for moisture content measurements are limited in their functionality and range. This paper presents a sensor that can be both factory installed and retrofitted, which can measure the moisture content through the cross-section of the member in a timber bridge. The sensor has been mounted on Sundbron bridge during manufacturing and retrofitted on Gislaved bridge. The ensuing measurements helped to adjust a design flaw on Gislaved bridge. Monitoring of Sundbron showed that the bridge deck dried up after the bridge had been exposed to sleet and snow during the on-site assembly of the stress laminated bridge deck

One challenge of monitoring and inspecting timber bridges is the difficulty of measuring the moisture content anywhere other than close to the surface. Damage or design mistakes leading to water penetration might not be detected in time, leading to costly repairs. By placing electrodes between the glulam beams, the moisture content through the bridge deck can be measured. Due to the logarithmic decrease of the resistance in wood as a function of electrode length, the model must be calibrated for measurement depth. Two models were created: one for electrode lengths of 50 mm and one for electrode lengths up to 1355 mm. The model for short electrodes differed by no more than 1 percentage points compared with the oven dry specimens. The model for long electrodes differed up to 2 percentage points for lengths up to 905 mm, and over that it could differ up to 4 percentage points.

This paper presents a structural health monitoring system to a timber bridge that will be built in Skellefteå during 2011. The bridge is a cable-stayed timber footbridge spanning 130 meters. The main objectives of using the health monitoring system are to verify the structural design and the long-term behavior of the bridge. The structural health monitoring system consists of GNSS receivers, MEMS accelerometers, laser positioning systems, wireless moisture content sensors, strain gauges and weather stations.

Monitoring displacements and weather impact of complex structures such as a large cable stayed footbridge generates large amount of data. In order to extract, visualize and classify health-monitoring data to get a better comprehension multivariate statistical analysis is a powerful tool. This paper is a screening to evaluate if principal component analysis is useful on health monitoring data. Principal component analysis (PCA) and projections to latent structures by means of partial least squares (PLS) modeling were used to achieve a better understanding of the complex interaction between bridge dynamics and weather effects. The results show that principal component analysis (PCA) give good overview of the collected data, and PLS modeling show that winds from east and west best explain bridge movements.

Construction of modern timber bridges has greatly increased during the last 20 years in Sweden. Wood as a construction material has several advantageous properties, e.g., it is renewable, sustainable, and aesthetically pleasing, but it is also susceptible to deterioration. To protect wood from deterioration and ensure the service life, the wood is either treated or somehow covered. This work evaluates a technology to monitor the moisture content in wood constructions. Monitoring the moisture content is important both to verify the constructive protection and for finding areas with elevated levels of moisture which might lead to a microbiological attack of the wood. In this work, a timber bridge was studied. The structure was equipped with six wireless sensors that measured the moisture content of the wood and the relative humidity every hour. Data for 744 days of the bridge are presented in this paper. Results show that the technology used to monitor the bridge generally works; however, there were issues due to communication problems and malfunction of sensors. This technology is promising for monitoring the state of wood constructions, but a more reliable sensor technology is warranted continuous remote monitoring of wood bridges over long periods of time.

When presenting images of wood obtained through x-ray computed tomography to an audience inexperienced in interpreting radiological images, explaining the correspondence between mass attenuation and features of wood could be time consuming and confusing. Realistically colourised attenuation images might be a suitable option in order to facilitate understanding of the images. Mass attenuation and colour of wood does not have a simple correlation, so naive grey-scale to colour conversion does not work. This paper describes how image quilting can be used to transfer colour information from a image pair where both mass attenuation and colour is known to a target mass attenuation image. An example of this method applied on scots pine shows that it is capable of retaining the major structures of wood, such as year rings and knots. The method could allow for easier understanding of simulation studies where logs scanned using x-ray computed tomography are virtually sawn.

This work evaluated the effect of timber quality features on the full-field mechanics of cross-laminated timber (CLT) panels. Panels were individuallysubjected to destructive out-of-plane loading in the principal panel orientation. A digital image correlation (DIC)-based technique was applied fornon-contact full-field measurement and analysis of panel mechanics. The results for 50 layers show that the stiffness of conventional CLT is largelyreduced by the shear resistance of transverse layers. Notably, heterogeneous timber features, such as knots, can reduce the propagation of shear.These results suggest an optimized panel assembly strategy that can be generalized: If shear is dimensioning in an area, e.g. the transverse or thecentral longitudinal layer, the use of knotty timber in that layers can reduce shear propagation. Knots in the compression zone in longitudinal layershave some negative impact, but knots have the largest negative impact in areas of longitudinal layers under tension. Therefore, it is suggested thecurrent grading criteria in the CLT standard be revised to allow the use of more knotty timber in the transverse layers of CLT; doing so could allowa more profitable use of otherwise low-grade timber while producing a stiffer product. The potential of panels constructed according to such anapproach may allow new applications for CLT in timber construction and should be further explored

This research assessed the mechanics of cross-laminated timber (CLT) panels with different alternating layer directions. A total of 20 industrially produced panels, configured with 0° longitudinal layers and transverse layers alternating at either ±45° or at 90° were subjected to destructive testing in bending. Four-point bending tests showed higher stiffness and strength for panels with ±45° alternating layers compared with the conventional 90° crosswise configuration. A noncontact numerical cross-correlation full-field measurement technique based on digital image correlation (DIC) was used as the main method of analysis for determining the mechanics in different scales. The results of the DIC analysis showed that the shear strain in bending was a more critical parameter in 90° layers than in adjacent 0° longitudinal layers of conventional configurations. Results infer that the use of CLT panels with ±45° can be beneficial to timber engineering construction and can induce an increase in the use of alternating layer laminates, especially in areas with shear.

This research evaluated the mechanics of cross-laminated timber (CLT) panels with different layer orientations. A total of 20 industrially produced panels, configured with 0° longitudinal layers and transverse layers alternating at either ±45° or the conventional 90°, were tested. Each panel was subjected to destructive out-of-plane testing in the principal panel orientation to evaluate stiffness and strength in bending. Four-point bending tests showed higher stiffness and strength for panels with ±45° alternating layers compared to 90°. A non-contact full-field measurement and analysis technique based on digital image correlation (DIC) was utilised for the main mechanical analysis at different scales. DIC evaluations of 100 CLT panel layers showed that a considerable part of the stiffness of conventional CLT is reduced by the shear resistance of transverse layers. Heterogeneous wooden features, such as knots, reduce the propagation of shear fraction along the layers. These results call into question the present grading criteria in the CLT standard: It is suggested that the current lower grading limit be adjusted for increased value-yield. The overall experimental results suggest the use of CLT panels with a ±45° layered configuration would be beneficial for timber engineering construction. They also motivate the use of alternatively angled layered laminates in design and construction, especially in areas subjected to shear. Based on these results, CLT should be further explored as a suitable product to potentially facilitate the use of wooden panels in more construction applications.

Engineered wood products, such as cross-laminated timber (CLT), are becoming more popular in the designs of modern sustainable buildings. This increased production of CLT requires more robust, yet less labour-intensive means to assess the material characteristics of whole CLT panels. In exploring ways of improving efficiency, this study explores multivariate image analysis (MIA) via partial least squares discriminant analysis (PLS-DA) machine learning as a means to classify CLT material features. CLT panels underwent nondestructive testing using near-infrared (NIR) hyperspectral imaging and X-ray computed tomography (CT) analysis. MIA was performed on these results to build predictive models for wood features, such as fibre alignment and knot type. The models showed that it was possible to classify material features on the surface of CLT using NIR alone; whilst when combined with X-ray data, it enhanced the predictive ability of material features throughout the CLT volume. These first results from such modelling have the potential to help map the chemical and physical material properties of CLT, improving the manufacturing efficiency of the product and allowing greater sustainability of engineered wood products.

Increasing awareness of sustainable building materials has led to interest in enhancing the structural performance of engineered wood products. This paper reports mechanical properties of cross-laminated timber (CLT) panels constructed with layers angled in an alternative configuration on a modified industrial CLT production line. Timber lamellae were adhesively bonded together in a single-step press procedure to form CLT panels. Transverse layers were laid at an angle of 45°, instead of the conventional 90° angle with respect to the longitudinal layers’ 0° angle. Tests were carried out on 20 five-layered CLT panels divided into two matched groups with either a 45° or a 90° configuration; an in-plane uniaxial compressive loading was applied in the principal orientation of the panels. These tests showed that the 45°-configured panels had a 30% higher compression stiffness and a 15% higher compression strength than the 90° configuration. The results also revealed that the 45°-configured CLT can be industrially produced without using more material than is required for conventional CLT 90° panels. In addition, the design possibility that the 45°-configured CLT can carry a given load while using less material also suggests that it is possible to use CLT in a wider range of structural applications.

In this paper, a series of experimental bending and compression tests were performed on cross-laminated timber (CLT) products with ±45° alternating layers, to evaluate their performance against conventional panels of 90° orientation. Engineered wood products, such as CLT with ±45° alternating layers can provide opportunities for greater use in larger and more sustainable timber constructions. A total of 40 panels, manufactured in an industrial CLT production line with either of these two configurations, were tested and compared. Panels were evaluated in bending tests n=20 and the remaining ones in compression tests. Results showed that 35% increased the strength in the four-point bending tests for panels containing ±45° alternating layers compared with the 90° alternating layers. Compression strength was increased by 15%. Stiffness increased by 15% in the four-point bending and 30% in the compression. The results indicate that CLT containing ±45° alternating layers has increased strength and stiffness compared to 90° alternating layers. These findings suggest that further developments in CLT are feasible in advanced building applications.

Bending tests were conducted with cross laminated timber (CLT) panels made using an alternating layer arrangement. Boards of Norway spruce were used to manufacture five-layer panels on an industrial CLT production line. In total, 20 samples were tested, consisting of two CLT configurations with 10 samples of each type: transverse layers at 45° and the conventional 90° arrangement. Sample dimensions were 95 mm × 590 mm × 2000 mm. The CLT panels were tested by four point bending in the main load-carrying direction in a flatwise panel layup. The results indicated that bending strength increased by 35% for elements assembled with 45° layers in comparison with 90° layers. Improved mechanical load bearing panel properties could lead to a larger span length with less material.

Wood is a pure, sustainable, renewable material. The increasing use of wood for construction can improve its sustainability. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. However, comparative market and economy studies are still scarce. In this study, the following assembling techniques were compared: laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. The production costs, durability, and ecological considerations were presented. This study was based on reviews of published works and information gathered from 27 leading wood product manufacturing companies in six European countries. The study shows that the various techniques of assembling multi-layer wooden construction panel elements are very different. Cross laminated timber (CLT) exhibited the best results in terms of cost and durability. With regard to ecological concerns, dovetailing is the best. Taking into account both durability and ecological considerations, wooden screw-doweling is the best. These alternatives give manufacturers some freedom of choice regarding the visibility of surfaces and the efficient use of lower-quality timber. CLT is the most cost-effective, is not patented, and is a well-established option on the market today.

Response surface methodology was used to optimize the refining conditions of Pinus massoniana cellulose fiber and to improve the mechanical properties of ultra-low density plant fiber composite (ULD_PFC). The effects and interactions of the pulp consistency (X1), the number of passes (X2), and the beating gap (X3) on the internal bond strength of ULD_PFC were investigated. The results showed that the optimum internal bond strength (91.72 ± 2.28 kPa) was obtained under the conditions of 8.0% pulp consistency, two passes through the refiner, and a 30.0 μm beating gap. Analysis of the physical properties of the fibers and handsheets showed that the fibrillation of fibers with optimum refining conditions was improved. Also, the tear index of the optimal specimen was 13.9% and 24.5% higher than specimen-1 with a lowest beating degree of 24 oSR and specimen-6 with a highest beating degree of 73 oSR, respectively. Consequently, the optimal refining conditions of the fibers are valid for preparing ULD_PFCs.

To obtain a suitable refining process for Pinus massoniana cellulose fibers (PMCF) and China fir cellulose fibers (CFCF), the effects of the beating gap and the pulp consistency on the physical properties and the morphology of the two cellulose fibers were investigated. The results showed that the physical properties of the PMCF and the CFCF were well affected by the beating gap and the pulp consistency. The CFCF showed a smaller weight-average length and width than that of the PMCF. The CFCF exhibited smaller weight-average length, width, and kink index than the PMCF. It is easy to get the high beating degree, indicating it is more easily to be refined. Additionally, the tensile index and burst index of PMCFP and CFCFP increased with increasing beating degree, while the tear index decreased. Compared to the CFCF, the paper made from PMCF had superior strength properties. Consequently, the PMCF was suitable for refining with a high pulp consistency and a medium beating gap, whereas the CFCF had a medium pulp consistency and a big beating gap.

To improve the mechanical properties of ultra-low density plant fiber composite (ULD_PFC), a suitable beating process to improve the fibrillation of cellulose fibers and maintain their length was investigated. The physical properties of cellulose fibers and papers, surface chemical bonds, and internal bond strength (IB) of ULD_PFCs were analyzed. The results showed that the beating degrees, degree of fibrillation, and fiber fines increased with the decreasing of beating gap, except for the fiber weight-average length, width, kink index, and curl index. The tensile index and burst index of paper showed an increasing trend with an increase in beating degree, while the tear index showed a decreasing trend. FTIR results showed that intermolecular and intramolecular hydrogen bonds in ULDF were broken. A suitable beating gap of 30 μm with a beating degree of 35 °SR was obtained. The corresponding IB was 50.9 kPa, which represented an increase of 73.1% over fibers with a beating degree of 13 °SR.

X-ray computed tomography (CT) is a powerful tool for the non-destructive study of dynamic moisture processes in wood and other bio-based materials. In the CT facilities at Luleå University of Technology, it is possible to study wood-moisture relations such as water absorption, drying and related material deformation under a temperature- and humidity-controlled environment.An increase in the use of bio-based materials in building construction has led to an increased interest in capillary phenomena in these materials, because of an increasing number of moisture-related damage in timber and hybrid-timber buildings. This article shows some examples of how different bio-materials used in construction interact with liquid water over time. The overall purpose has been to develop the CT technique as a powerful tool for the determination and visualization of capillary flow that can be a base for modelling and an increased understanding of moisture flow in new bio-based building materials.Early-stage observation of the behaviour of different traditional and new bio-based building materials shows that CT scanning, combined with image processing, has a high potential to be used in performing non-destructive and non-contact tests that can help to increase the knowledge of water-material interactions and develop building materials with an optimized performance.

Laminated self-bonded densified boards were obtained by pressing five veneers of beech(Fagus sylvatica L.) parallel-grain-oriented, without adhesive and without surface activation. Theboards were pressed according to an experimental design based on fifteen different combinations ofpressing parameters: temperature (200, 225, and 250°C), pressure (4, 5, and 6MPa), and time (240,300, and 360s). The image of the 40 board edges (radial sections) was analysed with ImageJ softwarein the red-green-blue (RGB) colour space. Brinell hardness tests were also performed. The resultsshow an almost linear relation between the brightness values (defined as the arithmetic mean of theRGB channels) and the Brinell hardness. It is suggested that brightness is a predictor of strength forself-bonded laminated boards.

Energy efficiency is an increasing requirement in the modern construction industry. The building envelope design plays an important role for increasing energy efficiency. The main objective of this study was to evaluate different roof and wall designs for energy efficiency in order to fulfil the future requirement for a sustainable building envelope. The comparative case studies were carried out by calculation and analysis of the different building parts. Of the roofs compared, the koljern-technique worked best. During the analysis of the wall constructs, an exterior wall with polyisocyanurate (PIR) insulation showed the best results. One of the conclusions was that better insulation is needed to meet future requirements for a sustainable building envelope. Another important finding was that the construction industry should be open to new technologies, such as the koljern-technique and PIR-insulation.

This report describes a measurement method, based on image processing, for calculating the proportion of active wood fractures in a sheet of particle board that has been pulled apart. This method gives an indirect measurement of the effectiveness of the glue in a particle board. The basic procedure is to separate different surfaces on both sides of the tensile fracture. The separation of the glue covered surfaces from wood surfaces has been enhanced by a development process. The separated surfaces for each side, represented in the form of a binary image, are added, and a proportion of the surface with coinciding wood surfaces represents the proportion of wood fractures. The error analysis covers the randomly obtained coinciding surfaces.

This paper presents and discusses the results and work carried out in a feasibility study, in cooperation with Swedish companies and a Japanese company to evaluate the possibility to introduce and adapt a new building system in Europe. The system is a column-beam systems developed in Japan and have been analyzed and evaluated in this project regarding to European conditions. The work carried out for about 18 months starting in June 2008 and finishing in 2010. The choice of the building system is determined by both performance and economy. The build system has a potential for various construction projects and has numerous advantages. The system flexibility should be increased to meet other types of construction and thereby increase its market potential. Each building is a unique object, so there is no pre-given solution what system is the best in each case.

Gran har idag begränsade möjligheter att förädlas till produkter för inomhusbruk på grund av förekomsten av kådlåpor. För att kunna vidareförädla gran i moderna processer krävs automatiska eller manuella metoder att ta reda på eventuell förekomst av defekter inne i materialet som helt kan nedklassa en slutprodukt. Kådlåpor har en form som följer en årsring och har därmed en i huvudsak 2-dimesionell form som följer tangentialytan i trädet. Detta medför att kådlåpan ofta ger upphov till tillfredsställande kontrast i två riktningar men inte vid genomlysning i den tredje i riktningen mot tangentialplanet. Förhållandet mellan kådlåpans tjocklek och övrigt trämaterial blir för litet och kådan/luftfickans annorlunda egenskaper som densitet, elektriska egenskaper eller fasskillnader ger inte urskiljbar kontrast. Kådlåpans varierande innehåll av luft och/eller kåda medför att detekteringssituationen blir mer komplex än om man hade ett homogent material i defekten. Projektet avser att i en förstudie nyttja och utvärdera känd teknik för att välja den sensor eller de kombinerade sensorsystem som kan hitta ej synliga kådlåpor i sågad gran. Slutmålet är detektering i en online lösning. Följande sensorer har testats: * för skanning av ytor: RGB, RGB + Uv belysning, Trakeideffekt, IR * för skanning av medelvärde av absorption i en riktning: Planröntgen * för tredimensionell representation av provkropp: CT-skanning och simulerad Cone-beam ScanningResultaten från ytskanningsförsöken visar att en industriell applikation är möjlig Resultaten från detektion av inre egenskaper är: * att CT -skanning fungerar för automatisk detektering men är ej möjligt att genomföra i realtidsapplikation med tillgänglig teknik* Planröntgen fungerar med kådlåpor parallella med djupdimensionen men inte för kådlåpor parallella med ytan * Cone-beam ger något bättre upplösning än i planröntgenfallet men sämre än CT rekonstruktion i det simulerade fallet. Idag finns inte de 2-D röntgensensorer som krävs för att omsätta detta i en industriell applikation.

Har funnit några lösningar? Ja, men inte inom prioriterade områden.RESULTAT: * Ny metod för förbättrad klassificering av kådlåpor på ytan identifierad och överlämnad till två leverantörer av avsyningssystem för träprodukter. Metoden som går att implementera i realtidssystem nyttjar den fluorescens som uppkommer vid UV belysning av kådlåpor. Kommersiellt intressant. * Möjlig metod att hitta kådlåpor i 3-dimensionella strukturer identifierad genom simulering. Fortfarande saknas kommersiella system och sensorer som kan nyttjas för en realtidslösning. Metoden klarar inte att upplösa kådlåpor i vissa riktningar i den simulerade provbiten och i ännu mindre utsträckning i en stock. * De försök som genomförts för att identifiera kådlåpor i en industriell tomograf visar på en möjlighet att detektera dem med normala bildbehandlings-algoritmer, problemen är för låg upplösningen för mindre kådlåpor samt att den tomograf som testats inte klarar av den miljö som finns i sågverk. * Vi har inte hittat några tecken på att logskannerdata eller andra stockbaserade yttreform- eller densitetsvariationsparametrar kan användas för att prediktera förekomst av kådlåpor i gran. FÖLJANDE KOMPLETTERANDE FÖRSÖK AV ANSATSER FÖR ATT LÖSA PROBLEMET HAR INTE GENOMFÖRTS DÅ LEDNINGSGRUPPEN BESLUTADE AVSLUTA PROJEKTET MED LÄGRE BUDGET ÄN PLANERAT: Beräkning av sannolikhet för förekomst av kådlåpor baserad på frekvensen på synliga ytor i sönderdelad stock. DVS om man hittar en eller flera kådlåpor på en planka skall man då sortera ut den? Sensortest med IR laser för att utreda maxdjup där icke synlig kådlåpa kan detekteras Test av mikrovågssensor

Picea abies , Pinus sylvestris), is reported, showing verified 92-94% correct classification. It is shown that compression wood classification could be reduced to an uncomplicated linear model using just a few spectral components where the most important one is around the limit for visible light going to the Ultraviolet spectra. This almost univariate behaviour for the model is not the common behaviour for other wood surface features

Classifying logs and boards has an essential economic impact on the forest products industry. In a modern production chain, quality control and raw material specifications are essential to fulfill production system demands as well as end user demands. The subject of the thesis is automatic grading of wood represented by its appearance in various stages of decomposition of a tree, i.e. as logs, boards, components or individual surface objects often labelled as defects. The main method used is based on multivariate measurements and data compression by means of principal component analysis (PCA) and prediction modelling with projections to latent structures (PLS). The thesis adresses mainly feature identification and feature extraction of properties that have an impact on automatic grading of sawn softwood boards. The features are modelled by means of their appearance in the multivariate image space obtained by scanning and integrating images utilizing different imaging sensors. The main goals of this thesis are: to introduce multivariate image analysis (MIA) and multivariate image projections to latent structures (MIPLS) combined with experimental design as a research tool for wood feature description and to give a survey of its applications to identify and extract features feasible for classification of softwood surfaces to investigate the use of an imaging spectrograph combined with a smart sensor for real time grading of sawn products to present the necessity of installing human evaluation and system interaction possibilities into automatic wood inspection systems to obtain good performance This thesis contributes to the wood research field by the multivariate approach so far with a limited use in wood technology research with a few outlayers. The main contributions are: the introduction of PLS and MIPLS as soft modelling tools for calibration and prediction modelling of wood features the evaluation of the imaging spectrograph/MIPLS concept to model the spectral behaviour of the interaction between visible light, the wood surface and the sensor the integration of a multisensor, i.e. a combination of sensors such as X-rays, R-waves and CCDs, and how to insert the obtained data into a linear or non linear model utilizing sufficient information from each sensor the recognition of useful information in softwood scanning. Utilizing electromagnetic wave interaction based sensor data, revealing the latent variables and their variations with respect to quality grading.

Projektets syfte är att ta fram kunskap, utveckla metoder och teknik somresulterar i sådana anpassade produktionsprocesser som leder till att produktkvalitet kan definieras i levererade träprodukter. Målsättningen är att anpassa torkningsprocessen utifrån virkets egenskaper så att ökade kvalitetskrav vad gäller fuktinnehåll i specifika slutprodukter säkras. Delresultat av projektet har spridits vid en välbesökt workshop. I detta projekt ska tre konkreta resultat spridas till träindustrin i form av en riktade workshops som visar den simuleringsmodell som ger måluppfyllelse för önskad precision i fuktmätning samt de krav som ställs på process och mätutrustning för att nå dit i den industriella tillämpningen. Ett viktigt resultat i detta projekt är att projektet tillsammans med internationella leverantörer utvärderat existerande in-line fuktkvotsmätare och sedan tillsammans med en av leverantörerna som anslöt till projektet vidareutvecklat kalibreringsmetoder anpassade för industribruk. Det tredje resultatet är kopplat till den nationella dialog och projekt som pågår kring fuktkvot i byggnadsvirke. Ett viktigt delprojekt är att ge en doktorand möjligheten att arbeta med tillämpad FoU i projektet vald teknik. Vi har i projektet valt Mikrovågsbaserad teknik för nästa generation fuktkvotsmätare efter utvärdering. Doktorandens insats är baserat på en egenutvecklade simuleringsmodellen och genomförs med en internationell mätsystemleverantör i samverkan Tekniska Universitet i Wien som utvecklar mikrovågssensorn.

Wood Technology research and education at Lulea University of Technology is located in Skelleftea 800 km north of Stockholm. At the campus about 25 persons are involved in education and research in Wood Technology. We are educating M.Sc. and post- graduate students in Wood Technology. The research at the campus includes the following main fields: -- Wood Machining - - Woodmetrics -- Wood Drying -- Wood Composites/Wood Material Science. Our research strategy is to obtain an individual treatment of every tree, board and piece of wood in order to get highest possible value for the forest products. This shall be accomplished by the aid of advanced scanning technology and computer technology. Woodmetrics means to measure different wood parameters in order to optimize the utilization of the raw material. Today we have the following projects in this field: Automatic wood inspection -- Color changes and moisture flow in drying processes -- Inner quality of logs and lumber - - Stem quality database -- Computer tomography -- Aesthetic properties of wood -- Market/industry/forest relations. In the Woodmetrics field we are using computer tomography, CCD cameras and other sensors in order to find and measure defects in trees and on boards. The signals are analyzed and classified with modern image analyzing techniques and advanced statistical methods.

This paper describes a consortia initiative in New Zealand established to focus on wood quality as a way of enhancing the wood product value, create more valuable forest and get revenue from wood quality tools and IP. Four key research areas has been tailored according to the participants needs supporting solid wood application * Resource characterisation * Improved appearance properties and performance * Improved structural properties and performance * Improved stability and straightness of wood products The idea of the three year program is to * Enhance wood product value by segregation of the resource by quality parameters * Produce a future high performance forest with big and straight trees * Generate Intellectual properties, IP, that support the development of a high technology cluster based on wood quality tools. The NZ, WQI Ltd cluster strategy is compared to similar ones made in the northern part of Sweden, SkeWood, and Träcentrum Norr, TCN. TCN is newly established by the Wood industry, Luleå University of Technology and SP/Trätek institute in terms of strategy, vision and organisation. Skewood is an ongoing academic wood research program with focus areas Wood building, Wood communication and Wood metrics. WQI Ltd and Skewood are analysed after half time in aspects of learning and knowledge building.

Smart Träbro i Smart Stad är ett projekt som genom gränsöverskridande samarbete ska ta fram data, modeller och verktyg för att mäta prestanda och kvalitet på en träbrokonstruktion. Genom ett samarbete mellan Luleå Tekniska Universitet (LTU) och Skellefteå kommun skapas exklusiva förutsättningar för att mäta och analysera träkonstruktioner i syfte att stärka konkurrenskraften för trävaruindustrin.

This study was carried out to test methods for separating knots from clearwood in a digital image stack when scanning for internal defects with a medical CT-scanner. Scots pine knots, represented by its tangential surface density image extracted from a CT-image stack, have been classified by two different methods showing equal results. The knots are classified in four knot types by an Artificial Back-propagation Neural Network (ANN) and a Partial Least Squares Modelling with Latent Variables (PLS) model. The classification precision of aim of four different knot types, is between 85% and 97%. The results indicate that both methods may be useful tools in order to describe and classify knots in concentric surfaces around the pith in CT-images and thereby extract parametrical models from CT raw data image stacks. A simplified classification model has been obtained, by analysing the learning patterns in both the ANN and PLS model, that classify knots and transform density related data to segmented and classified parametrical descriptions.

Resin pockets, common in softwoods, are small lenses of resin oriented along annual rings. When using Norway spruce for making joinery products, resin pockets are considered as serious defect. CT- and RGB-scanning with various illumination were tested for contrast between resin-pockets and other wood properties. UV light in combination with the RGB-sensor showed good possibility to detect resin pockets on open wood surfaces while the other methods showed less contrast between the resin pockets and other wood properties. Segmentation of resin pockets within the 3-D volume was compared for the different sensors using 3-D graphical methods extracting segmentation from 2-D slices of the test piece. The obtained 3-D volumes can be used for investigation of the 3-D spatial representation of resin pockets in spruce.