scholarly journals New Perspectives for LVL Manufacturing from Wood of Heterogeneous Quality—Part. 1: Veneer Mechanical Grading Based on Online Local Wood Fiber Orientation Measurement

Forests ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1264 ◽  
Author(s):  
Robin Duriot ◽  
Guillaume Pot ◽  
Stéphane Girardon ◽  
Benjamin Roux ◽  
Bertrand Marcon ◽  
...  
Keyword(s):  
Fiber Orientation ◽  
Wood Fiber ◽  
Average Density ◽  
Measuring Instrument ◽  
Orientation Measurement ◽  
Sorting Method ◽  
Heterogeneous Quality ◽  
Local Properties ◽  
Sawmilling Industry ◽  
Local Fiber

The grading of wood veneers according to their true mechanical potential is an important issue in the peeling industry. Unlike in the sawmilling industry, this activity does not currently estimate the local properties of production. The potential of the tracheid effect, which enables local fiber orientation measurement, has been widely documented for sawn products. A measuring instrument exploiting this technology and implemented on a peeling line was developed, enabling us to obtain the fiber orientation locally which, together with global density, allowed us to model the local elastic properties of each veneer. A sorting method using this data was developed and is presented here. It was applied to 286 veneers from several logs of French Douglas fir, and was compared to a widely used sorting method based on veneer appearance defects. The effectiveness of both grading approaches was quantified according to mechanical criteria. This study shows that the sorting method used (based on local fiber orientation and average density) allows for better theorical quality discrimination according to the mechanical potential. This article is the first in a series, with the overall aim of enhancing the use of heterogeneous wood veneers in the manufacturing of maximized-performance LVL by veneer grading and optimized positioning as well as material mechanical property modelization.

scholarly journals Oriented collagen fibers direct tumor cell intravasation

2016 ◽  
Vol 113 (40) ◽  
pp. 11208-11213 ◽  
Author(s):  
Weijing Han ◽  
Shaohua Chen ◽  
Wei Yuan ◽  
Qihui Fan ◽  
Jianxiang Tian ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Extracellular Matrix ◽  
Tumor Cell ◽  
Tumor Cells ◽  
Fiber Orientation ◽  
Breast Cancer Cells ◽  
Protein Concentration ◽  
Collagen Fiber ◽  
Fiber Alignment ◽  
Local Fiber

In this work, we constructed a Collagen I–Matrigel composite extracellular matrix (ECM). The composite ECM was used to determine the influence of the local collagen fiber orientation on the collective intravasation ability of tumor cells. We found that the local fiber alignment enhanced cell–ECM interactions. Specifically, metastatic MDA-MB-231 breast cancer cells followed the local fiber alignment direction during the intravasation into rigid Matrigel (∼10 mg/mL protein concentration).

scholarly journals Alterations in Microstructure and Local Fiber Orientation of White Matter Are Associated with Outcome after Mild Traumatic Brain Injury

2020 ◽  
Vol 37 (24) ◽  
pp. 2616-2623
Author(s):  
Mehrbod Mohammadian ◽  
Timo Roine ◽  
Jussi Hirvonen ◽  
Timo Kurki ◽  
Jussi P. Posti ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
White Matter ◽  
Mild Traumatic Brain Injury ◽  
Fiber Orientation ◽  
Local Fiber

Region-of-Interest X-Ray Tomography for the Non-Destructive Characterization of Local Fiber Orientation in Large Fiber Composite Parts

2019 ◽  
Vol 809 ◽  
pp. 587-593
Author(s):  
Simon Zabler ◽  
Katja Schladitz ◽  
Kilian Dremel ◽  
Jonas Graetz ◽  
Dascha Dobrovolskij
Keyword(s):  
Computed Tomography ◽  
Spatial Resolution ◽  
Fiber Orientation ◽  
Fiber Composite ◽  
Three Dimensional ◽  
Region Of Interest ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Anisotropic Thermal Conductivity ◽  
Local Fiber

To detect and characterize materials defects in fiber composites as well as for evaluatingthe three-dimensional local fiber orientation in the latter, X-ray micro-CT is the preferred methodof choice. When micro computed tomography is applied to inspect large components, the method isreferred to as region-of-interest computed tomography. Parts can be as large as 10 cm wide and 1 mlong, while the measurement volume of micro computed tomography is a cylinder of only 4 − 5 mmdiameter (typical wall thickness of fiber composite parts). In this report, the potentials and limits ofregion-of-interest computed tomography are discussed with regard to spatial resolution and precisionwhen evaluating defects and local fiber orientation in squeeze cast components. The micro computedtomography scanner metRIC at Fraunhofer‘s Development Center X-ray Technology EZRT deliversregion-of-interest computed tomography up to a spatial resolution of 2 μm/voxel, which is sufficientfor determining the orientation of natural or synthetic fibers, wood, carbon and glass. The mean localfiber orientation is estimated on an isotropic structuring element of approximately 0.1 mm length bymeans of volume image analysis (MAVI software package by Fraunhofer ITWM). Knowing the exactlocal fiber orientation is critical for estimating anisotropic thermal conductivity and materials strength.

Orientation measurement of graphically simulated nanoscale electrospun fibrous structures using particle-based modeling and 2-D metaball fitting

2018 ◽  
Vol 30 (1) ◽  
pp. 122-136
Author(s):  
Sun Hee Moon ◽  
Kyung Hwa Hong ◽  
Jaewoong Lee ◽  
In Hwan Sul
Keyword(s):  
Boundary Conditions ◽  
Conjugate Gradient ◽  
Fiber Orientation ◽  
Electrospun Fiber ◽  
Time Integration ◽  
Automatic Measurement ◽  
Electrospinning Process ◽  
Preconditioned Conjugate Gradient ◽  
Orientation Measurement ◽  
Content Type

Purpose The purpose of this paper is to provide an efficient tool for simulating electrospinning process in virtual 3D space and optimizing experimental parameters. The fiber orientation from virtual or real electrospinning process can be easily measured using the image analysis technique. Using the semi-implicit Euler integration, the time integration can be more fast and stable, which enabled optimization of the electrospinning process. Also boundary conditions can be easily adopted during conjugate gradient matrix solving step. Design/methodology/approach To simulate the electrospinning process, the authors have adopted a particle-based modeling technique using the molecular dynamics theory, which is known to be suitable for modeling materials with nonlinear and nonhomogeneous behavior such as fibers or fabrics. Gravitational, tensional, and electrostatical forces and their Jacobians were carefully defined and chosen to maintain the stability of the governing equation. Preconditioned conjugate gradient method was used to solve the matrix iteratively with boundary conditions. The 2-D metaball fitting technique, which was applied in the previous research (Sul et al., 2009) on experimental nanofiber scanning electron microscopy images, was utilized with virtual nanofiber images. A staircase function and a new shading language were proposed to automatically calculate the orientation and radius distribution of the graphically simulated electrospun fiber structures. The automatic measurement procedure was verified via graphically designed virtual replica images. Also the orientation tendency acquired from the simulation was compared with that of experimental data. Findings Simulation result of fiber orientation showed linear relationship with the collecting drum speed. Use of particle-based method generated a simple system to simulate electrospinning process. Originality/value The semi-implicit Euler integration was applied to the electrospinning process and the final linear system was numerically stable to solve.

scholarly journals Local fiber orientation from X-ray region-of-interest computed tomography of large fiber reinforced composite components

2019 ◽  
Vol 183 ◽  
pp. 107786 ◽  
Author(s):  
Thomas Baranowski ◽  
Dascha Dobrovolskij ◽  
Kilian Dremel ◽  
Astrid Hölzing ◽  
Günter Lohfink ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Fiber Orientation ◽  
Region Of Interest ◽  
Fiber Reinforced ◽  
Fiber Reinforced Composite ◽  
X Ray ◽  
Reinforced Composite ◽  
Large Fiber ◽  
Local Fiber

Fiber orientation measurement of fiber injection molded nonwovens by image analysis

2020 ◽  
pp. 004051752094890
Author(s):  
Patrick Moll ◽  
Shaofan Wang ◽  
Sven Coutandin ◽  
Jürgen Fleischer
Keyword(s):  
Image Analysis ◽  
Fourier Transform ◽  
Fast Fourier Transform ◽  
Fiber Orientation ◽  
Transmitted Light ◽  
Structure Tensor ◽  
Orientation Measurement ◽  
Tensor Methods ◽  
Fiber Orientation Distribution ◽  
Injection Molded

The fiber injection molding process is an innovative approach for the manufacturing of long fiber nonwoven preforms with little to no waste. An important property for the mechanical characteristics of the composite parts is the fiber orientation of the fiber injection molded nonwovens. In this paper a newly developed assemble method based on Fast Fourier Transform and improved Structure Tensor methods for the computation of the fiber orientation distribution in the local orientation by image analysis of transmitted light images is presented. For the computation of the fiber orientation, the Fast Fourier Transform and Structure Tensor methods are used. The new method is evaluated using simulated images and transmitted light images of real nonwovens to evaluate their accuracy. The computed fiber orientation distributions are compared to reference distributions by means of the Kullback–Leibler divergence. It is shown that the assemble method can perform accurate and reliable measurement of fiber orientation measurement and the modified Structure Tensor method improves results significantly compared to the current state of the art.

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