Real Wood Research Articles

In-situ electrochemical impedance analysis of a commercial SOFC stack fueled by real wood gas

The combination of solid oxide fuel cells (SOFCs) and wood gasification has the potential to significantly increase renewable electricity production and decrease emissions. Depending on the quality of the wood gas, degradation processes have a significant impact on the reliability and lifetime of the SOFC. Using electrochemical impedance spectroscopy (EIS) and subsequent distribution of relaxation times (DRT) analysis, the impact on the degradation of coupling wood gasification with a commercial SOFC stack is determined in this study. The thermal behavior of the SOFC stack under various operating conditions, as well as various synthetic wood gas mixtures classified by their hydrogen-to-carbon (H/C) ratio, was assessed. The decrease in the H/C ratio from 8 to 1, observed during syngas and real wood gas operation, leads to a rightward shift in the Nyquist plots, suggesting an increase in the SOFC stack's impedance. Correlations between variations in the H/C ratio and their effects on anodic electrooxidation, ionic conduction, gas transport, and diffusion were identified using DRT analysis to interpret the EIS results. By incorporating an upstream desulfurization system and ensuring an H/C ratio greater than 2, the coupling of biomass gasification with the SOFC stack was stable to degradation issues.

Learned Inference of Annual Ring Pattern of Solid Wood

AbstractWe propose a method for inferring the internal anisotropic volumetric texture of a given wood block from annotated photographs of its external surfaces. The global structure of the annual ring pattern is represented using a continuous spatial scalar field referred to as the growth time field (GTF). First, we train a generic neural model that can represent various GTFs using procedurally generated training data. Next, we fit the generic model to the GTF of a given wood block based on surface annotations. Finally, we convert the GTF to an annual ring field (ARF) revealing the layered pattern and apply neural style transfer to render orientation‐dependent small‐scale features and colors on a cut surface. We show rendered results of various physically cut real wood samples. Our method has physical and virtual applications such as cut‐preview before subtractive fabricating solid wood artifacts and simulating object breaking.

Reducing the impact of biomass combustion in residential units on local air quality by using innovative low-loading Pt-based heterogeneous catalyst

There are several published studies evaluating the potential of platinum and palladium-based catalysts for real flue gas purification, however, the need to reduce the mass fraction of precious metals and the effect of this process is often neglected. This study aimed to assess the influence of two catalysts on the overall flue gas composition formed during combustion in a pellet burner operated to mimic the operation of a real wood log stove. Commercial Pt–Pd-based (CAT A) and Pt-based (CAT B) catalysts with innovative sol-gel coatings and a reduced amount of active substance were used. The CO, OGC and PM conversion rates of CAT A reached 87.8%, 37.0% and 25.2%, while the removal efficiency of CAT B reached 85.8%, 37.8% and 18.8%, respectively. The decrease of organic carbon by the catalysts ranged from 28% to 49% in the case of CAT A and from 13% to 60% in the case of Cat B. The concentrations of PAHs emitted seem to indicate a less carcinogenic composition when catalytic converters are used than without these flue gas treatment units.

Exploring the potential of StyleGAN for modeling high-quality and diverse digital wood textures: Towards advancements in the wood industry

Wood texture is pivotal in maximizing the value of trees and timber resources. Consequently, digital modeling and simulation of wood texture have become essential in wood science and industry. Therefore, researching simulation modeling techniques for digital wood texture has significant implications for advancing wood science and industry. This paper introduces a novel approach to modeling and simulating wood texture, focusing on the perspective of deep learning. The proposed method explored the viability of utilizing the StyleGAN model to generate digital wood texture. Fréchet Inception Distance(FID), visual Turing tests, and 1/f fluctuation spectrum analysis were used to evaluate the effectiveness of the digital wood texture models. Additionally, various control techniques were discussed for generating digital wood texture using StyleGAN models. The experimental results strongly indicated that the StyleGAN model exhibits robust capabilities in generating digital wood texture, as evidenced by an FID index of 13. Moreover, the visual Turing tests revealed that professional identification was similar to random guessing, while the fluctuation spectrum analysis demonstrated pixel distribution frequencies similar to those observed in real wood textures. Furthermore, in terms of controlling the simulation of digital wood texture, the StyleGAN model demonstrated remarkable abilities surpassing any previous models based on physical modeling. By fine-tuning truncation parameters and employing network layer mixing techniques, the model could generate the wood texture of various tree species, demonstrating outstanding generalization capabilities.

Thermal conductivity assessment of wood using micro computed tomography based finite element analysis (μCT-based FEA)

The paper presents a progressive methodology that combines X-ray micro computed tomography (μCT) and finite element analysis (FEA) to test the thermal conductivity of wood at the mesoscale level. μCT enables the three-dimensional (3D) modeling of real wood material with two-phase components (i.e., earlywood and latewood). The analytical wood conductivities from μCT-based FEA agree well with those from the theoretical analysis and the existing experimental findings. Using μCT-based FEA also enables the numerical evaluation of the effects of grain orientation, porosity, and water saturation degree on thermal conductivity of wood. Compared to current testing methods, the proposed μCT-based FEA has the advantages of high-resolution modeling, rapid evaluation, and high reproducibility of wood thermal conduction.

Introduction of a New Line of High-Density Polyethylene (HDPE) Based Furniture

Industrial development usually has an inherent environmental impact due to the unsustainable practice adopted to support this growth. Furniture industry is an example of this trend since its growth is sustained by the exploitation of the forest from where the timber is extracted. High density polyethylene (HDPE) has been selected as a suitable alternative for wood because of its physical properties, economic benefits and environmental friendly characteristics. The reports will illustrate how furniture industry creates environmental pressure, aspects that will be affected by adopting the new sustainable philosophy, cost saving opportunities and example of best practices currently implemented. HDPE based furniture are made from the same material used in containers for milk, shampoo, oil and other products, which makes it highly recyclable. Furthermore, at the end of their working life the product can also be recycle, making them totally eco-friendly and economically profitable. Moreover, these products offer excellent resistance and longevity characteristics that closely resemble and exceed the ones found in real wood. Finally this sustainable practice has already been successfully implemented by many companies around the world for several years.

An object-oriented architecture to couple simulators and their machine learning surrogates models in the context of digital shadows

This article studies a method to couple two digital models in the context of digital twins. The first model is a simulation model which is supposed to be very accurate but computationally intensive. The second is a fast but approximate machine-learning model of the simulation. Both models serve, therefore, the same prediction task in an online environment but have different advantages and drawbacks. An object-oriented architecture is introduced to implement the proposed coupling strategy. Numerical experiment results on four datasets are also provided to evaluate the performances of the proposed strategy and compare it with a baseline. Three of these datasets originate from the University of California, Irvine machine learning repository. The last one originates from the Canadian forest product industry and contains the outputs of sawing simulation for real wood logs. These experiments demonstrate that the proposed method allows to consistently reduce the average error of the couple predictions.

A Study On Algorithm-Generated Assembly Of Curved I And Y Shaped Branches For Temporary Shelters

The aim of the research is to propose a workflow and an assembly tool for architecture based on curved wood in its whole unmodified form e. g., wasted crown wood from producing sawn timber, wood thinnings cut during forest management or just branches found in the woods. This paper describes the workflow from collecting the real wood to algorithmically generating a shelter structure. The authors propose a new spatial system suited for irregular elements along with a computer tool to generate all possible variations out of the input branch data. The merit of this approach is that it could fit any number of randomly sized branches together into combinatorically predefined structural shell surface, made of irregular triangles. The fitting is based on different parameters such as size, weight, curvature of the branches and can be filtered by the structure's height, interior volume, plan area, surface area of the shell, etc. The user can control these parameters to select the best solution to be build. This shelter generation method could be deployed to smart devices and used remotely in disaster mitigation and relief after earthquakes, floods or in times of wildfires and other emergency situations. This approach to architecture could prove useful because of its speed and ease of construction, low market price, as well as introducing a new way of shelter design generation.

Wood anatomy teaching: Example of the Vocational School of Forestry

The teaching of wood anatomy is difficult because of the Latin and foreign terminology and the great number of concepts, definitions, terms, and topics that must be learned and that pose difficulties in understanding for most students. The aim of this study was to describe developed traditional methods and adapt new methods in order to explain wood anatomy more clearly to students in both online and face-to-face education. The teaching of the Wood Structure and Identification course at the Vocational School of Forestry was observed and evaluated over the period of two academic terms (one during the Covid-19 pandemic). Teaching methods used in the wood anatomy course were described in detail. Lesson materials and homework were evaluated. When the usual methods were diversified and enriched with visuals and samples brought to the classroom, the students showed more interest in the lesson. As a result of the student drawing and modelling assignments, the lesson was reviewed and reinforced, which enabled the students to focus on the subject and consequently, to understand and learn more easily. It has determined that all teaching methods can be applied easily in both education periods, except using real wood samples method in online education.

A Modeling Approach on the Correction Model of the Chromatic Aberration of Scanned Wood Grain Images

There always exists subjective and objective color differences between digital wood grain and real wood grain, making it difficult to replicate the color of natural timber. Therefore, we described a novel method of correcting the chromatic aberration of scanned wood grain to maximally restore the objective color information of the real wood grain. A point-to-point correction model of chromatic aberration between the scanned wood grain and the measured wood grain was established based on Circle 1 by adjusting the three channels (sR, sG, and sB) of the scanned images. A conversion of the color space was conducted using the mutual conversion formulas. The color change of the scanned images before and after the correction was evaluated through the L∗a∗b∗ color-mode-based ΔE∗. and the lαβ color-model-based CIQI (Color Image Quality Index) and CQE (Color Quality Enhancement). The experimental results showed that the chromatic aberration ΔE∗ between the scanned wood grain and the measured wood grain decreased and the colorfulness index CIQI of the scanned wood grain increased for most wood specimens after the correction. The values of ΔE∗ of the twenty kinds of wood specimens decreased by an average of 3.1 in Circle 1 and 2.3 in Circle 2, thus the correction model established based on Circle 1 was effective. The color of the scanned wood grain was more consistent with that of the originals after the correction, which would provide a more accurate color information for the reproductions of wood grain and had an important practical significance.

Wood Product Tracking Using an Improved AKAZE Method in Wood Traceability System

Tracking of the wood product is an important technology in the trade activity of rare plants. Normally, the factories use Quick Response (QR) and Radio-Frequency Identification (RFID) to identify the individual wood product, but these technologies are not safe enough because they can be easily falsified. It can be seen that traditional methods are hard to catch the detail of the slim wood texture from the wood product. In this study, a novel method is employed to resolve these problems using a biometric feature on the surface of the real wood product to distinguish the individual wood product. AKAZE is used to extract the key-point of wood texture. A sub-area detection technique along with a serialization method is then developed to improve the rate of identification. The sub-area detection technique deals with picking out a sub-region in which there are enough AKAZE points as small as possible. The serialization method is also utilized to reduce the redundant process of feature extraction. The experimental results demonstrate that the values of accuracy, recall, and F1 reach 0.98, 0.96, and 0.96, respectively. The match time that uses serialized function is reduced to 1/3 of which has no application in the original image. The validated results also reveal that our proposed methodology improves the robustness of the wood product identification, and it can be used in Wood Traceability System (WTS) with the blockchain to resolve the digital trust problem and the fast distinction issues of the real wood product.

Wood assortment tables of Norway spruce (Picea abies Karst.) for Canton 10 of Federation B&H

Current tables of wood assortments for the most important tree species in B&H were made almost 50 years ago. There is an indication that real forest wood assortments are different than the one derived from assortment tables in-use, both in terms of quality and dimensions. In the meantime, from the creation of the existing tables until today, the standards of production of forest wood assortments have changed, so that the fact of inaccuracy of the existing assortment tables is unquestionable. This continually creates a variety of problems in the ongoing operations of forestry companies. The main aim of this paper is to create wood assortment tables whose assortment of wood products will correlate with the current market conditions. The research was conducted in the area of the Canton 10 in FB&H. A sample of 393 spruce trees was used as a database to produce this paper. The bucking of the sample trees was carried out in accordance with the valid norms and customer requirements with regards to the dimensions of forest wood products. Data processing was performed using methods of simple and multiple regressions, variance analysis as well as their combinations by the Generalized Linear Models method. Independent factors were breast diameter (DBH), technical quality class and the height of the trees. The share of wood assortments was determined through 10 different mathematical models, and it was found that all independent variables had a statistically significant influence on the dependent variables- volume of particular assortments or group of assortments. The share of logs is growing rapidly with the increase of tree diameter and decreases with decreasing of their technical quality. The influence of tree height primarily correlated with tree volume increase. Trees having better assortment quality, have tree heights higher than average for the same diameter class. The results of the research are presented in the form of tables as percentage share of wood assortment classes. The obtained results can be used as wood assortment tables in the research area.

Determination of Pyrethroid Residues in Wooden Toys by Gas Chromatography and Gas Chromatography–Mass Spectrometry

A novel method for the determination of pyrethroid pesticide residues in wooden toys was developed. Wooden toy samples were extracted with petroleum ether−acetone (1 : 1, v/v), cleaned up on a florisil solid phase extraction cartridge and determined by gas chromatography equipped with electron capture detector (GC−ECD), followed by validation using gas chromatography−mass spectrometry (GC−MS) with negative chemical ionization. Calibration curves were linear in the range of 0.02–0.5 mg/kg with correlation coefficients exceeding 0.9975 for GC−ECD and GC−MS. At spiked concentrations of 0.1, 0.2 and 0.5 mg/kg, the average recoveries and relative standard deviations were 82–97% and 1.5–7.8%, respectively. The limit of quantification for each analyte was 0.1 mg/kg, which satisfied the current maximum residue limit permitted in wooden toys. Results also showed that the developed method could be successfully applied to determine permethrin, cypermethrin, cyfluthrin, deltamethrin residues in real wooden toy samples.

Digital 3D Wood Texture: UV-Curable Inkjet Printing on Board Surface

Natural wood textures are appreciated in most forest products industries for their appealing visual characteristics including grain and color, but also their fine surface tactile sensation. The following presents an ultraviolet (UV)-curable inkjet technology printing 3D wood texture on wood-based substrate by image processing and surface treatment. The UV printing was created from scanned digital images of a real wood surface and processed in graphics software. The images were converted to grayscale graphics by selecting color range and setting the parameter of fuzziness. The grayscale images were printed as 3D texture height simulation on the substrates and coated by printing the color images as texture mapping. Based on these wood texture digital images, the marquetry art is also considered in the images processing design to increase the artistry of the printed materials. The medium-density fiberboard (MDF) coated printing marquetry surface replicate realistic natural 3D wood texture surface layers on wood-based panels and imitated the effect of handcrafted wood art works. This study proves that printing 3D texture surface material is creative and valuable with ecologically friendly, low-consumption UV-curable inkjet technology and provides a feasible and scalable approach in flooring/furniture/decorative architectural panels.

Short-term and long-term longitudinal load tests of wooden rods

The purpose of the experimental studies was to verify the reliability of the method for solving the stability problem of centrally compressed rods, taking into account the creep of wood. To achieve this goal, it is necessary to have a diagram of deformations of real wood and experimental data on the behavior of rods of the same wood under continuous load. Experimental studies include short-term axial compression tests of small specimens with recording of load-deformation diagrams, as well as short-term and long-term tests of cores of different flexibility for central compression, the description of which is presented in this article. The authors of the paper obtained the values of critical stresses under longitudinal bending for wooden rods with different lengths and flexibility. These results have a high convergence with the values obtained as a result of theoretical calculations.

Computational Parquetry

Parquetry is the art and craft of decorating a surface with a pattern of differently colored veneers of wood, stone, or other materials. Traditionally, the process of designing and making parquetry has been driven by color, using the texture found in real wood only for stylization or as a decorative effect. Here, we introduce a computational pipeline that draws from the rich natural structure of strongly textured real-world veneers as a source of detail to approximate a target image as faithfully as possible using a manageable number of parts. This challenge is closely related to the established problems of patch-based image synthesis and stylization in some ways, but fundamentally different in others. Most importantly, the limited availability of resources (any piece of wood can only be used once) turns the relatively simple problem of finding the right piece for the target location into the combinatorial problem of finding optimal parts while avoiding resource collisions. We introduce an algorithm that efficiently solves an approximation to the problem. It further addresses challenges like gamut mapping, feature characterization, and the search for fabricable cuts. We demonstrate the effectiveness of the system by fabricating a selection of pieces of parquetry from different kinds of unstained wood veneer.

KERAGAMAN JAMUR PADA LOG DAN KAYU GERGAJIAN NYATOH (Palaquium sp)

Wood is one medium that can be a place to grow fungus. The chemical components forming wood in the form of holocellulose and lignin which can be overhauled by fungi into simple compounds are a food source for the fungus. This study aims to identify the type of fungus that grows on the log and or sawn wood of Palaquium sp so that it can provide information about the diversity of fungal species, both useful and those that are pathogenic. The process of identifying mushrooms is done by observing the macroscopic and microscopic characteristics of the fungus. The macroscopic characteristics observed were mushroom color and mushroom fruit body shape. Observations of microscopic features include hyphae, spores, sporangium, conidia, and conidiophores. Macroscopic and microscopic observations identified eight types of fungi that grow on real wood, namely Dacryopinax spathularia, Pycnoporus sanguineus, Schizophyllum commune, Cunninghamella echinulata, Penicillium, Trichoderma, Absidia ramosa and Aspergillus. There are six types of fungi which are wood rot fungi, namely D. spathularia; P. sanguineus; S. commune; Penicillium, Trichoderma, and Aspergillus. The other two types are coloring fungi, namely C. echinulata and A. ramosa.

Bio-based consolidants for waterlogged archaeological wood: Assessment of the performance and optimization of the diagnostic protocol

Abstract New bio-based polymers used as consolidants for waterlogged archaeological wood were studied and their performance on real wooden samples was assessed. In particular, three oligoamides (oligo ethylene- l -tartaramide, oligo esamethylene- l -tartaramide and copolymer between ethylenediamine, adipic and tartaric acids) and allyl α,α′-trehalose/vinyl alcohol (ATR/VOH) copolymer were selected as consolidants. The affinity for wood and the reversibility of the treatments were evaluated together with certain physical properties of treated wood, i.e. maximum water content (MWC), basic density (ρb) and volumetric shrinkage (βv). A specific diagnostic protocol was optimized in order to obtain reproducible and reliable results. A good affinity for a degraded wood rich in lignin was demonstrated for all tested consolidants. For what concerns the reversibility of the treatments, the oligoamides showed higher reversibility than the ATR/VOH copolymer. The penetration ability was good for all selected products. Good results in terms of MWC reduction and ρb increase were obtained with the oligo esamethylene- L -tartaramide, the oligo ethylene- L -tartaramide and the ATR/VOH copolymer.

Small-angle scattering model for efficient characterization of wood nanostructure and moisture behaviour.

Small-angle scattering methods allow an efficient characterization of the hierarchical structure of wood and other cellulosic materials. However, their full utilization would require an analytical model to fit the experimental data. This contribution presents a small-angle scattering model tailored to the analysis of wood samples. The model is based on infinitely long cylinders packed in a hexagonal array with paracrystalline distortion, adapted to the particular purpose of modelling the packing of cellulose microfibrils in the secondary cell wall of wood. The new model has been validated with small-angle neutron and X-ray scattering data from real wood samples at various moisture contents. The model yields reasonable numerical values for the microfibril diameter (2.1-2.5 nm) and packing distance (4 and 3 nm in wet and dry states, respectively) and comparable results between the two methods. It is particularly applicable to wet wood samples and allows changes in the packing of cellulose microfibrils to be followed as a function of moisture content.

Quantitative image analysis of acoustic tomography in woods

The development of acoustic techniques for wood analysis through tomography has enabled the generation of images by means of nondestructive techniques. These images allow for the evaluation of the internal condition of wood trunks. This type of evaluation provides valuable information since the internal defects (e.g. holes) in the wood are difficult to identify—especially in its early stages of development. Whereas there is a substantial body of work that aims to improve these images by applying new interpolation and inspection techniques, the assessment of these techniques has traditionally been carried out via a bare visual analysis or inspection of the real wood trunk. In this work, an approach is proposed to quantitatively assess interpolation methods regarding their ability to correctly detect faults in the wood. This approach is based on a confusion matrix that allows for the computation of accuracy, reliability and recall. An experiment is presented using images from the cross-section of wood trunks generated by two interpolation methods applied for internal-hole detection: (1) an interpolation method using surrounding points and (2) the Ellipse Based Spatial Interpolation. The results demonstrated the effectiveness of the approach in quantitatively assessing and comparing these methods.