Surface data of three differently oriented forming mats were obtained by profile measuring sensor and by digital camera. Surface profile data were obtained by a profile measuring sensor whereas digital image data obtained by a digital camera. Each data was analyzed in two ways, namely two-dimensional fast Fourier transform analyses and image processing. Orientation functions were compared with chip orientation data obtained by visual inspections. Orientation degrees were calculated from orientation functions. Averaging filter, Laplacian filters and threshold filter were adopted to surface profile data and digital image data to enhance chip edge points. In order to evaluate accuracy of edge enhancing, the number of edge point numbers were counted and were judged whether they are on edge or not by visual inspections. Percentiles of correct edge points were calculated from filtered images. The results can be summarized as follows :
1) FFT analyses can be used to estimate chip orientation on surface profile data and digital image data.
2) Orientation degree obtained from surface profiles and digital images, and chip orientation from visual inspections agreed approximately.

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Today, the probabilistic model adopting Monte Carlo simulation is the established method to predict the modulus of rupture (MOR) of glued-laminated beams.
However, it would be significant to calculate the MOR by another numerical analytical method. Therefore, we propose in this paper an elasto-plastic analytical method to predict the bending properties of glued-laminated timber beams.
The method is the application of the Rigid Bodies-Spring Model (RBSM). Load-deflection curves, proportional-limit bending stresses (σ_p) and MOR of glued-laminated beams were analyzed using the following assumptions.
1) Glued-laminated beams were assumed to be multi-layered beams.
2) Stiffness equations for simple beams were applied to the spring elements parallel to the longitudinal direction of the beams. Stiffness equations for two-dimensional plane-stress problems were applied to the spring elements perpendicular to the longitudinal direction.
3) A quadratic formula considering bending moment and axial force was adopted as the failure criterion of the beams.
To verify the validity of the present expression, the calculated σ_p and MOR of glulam beams were compared with previous results. A good correlation was demonstrated between the predictions of our theoretical model and experimental and calculated ones obtained by other researchers. Consequently, the analytical method based on the RBSM proposed in this study has been shown to be valid.

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Lagscrewbolts were developed as a simple and economical moment-resisting connector for glulam frame constructions. This new type of connector is expected to show high pull-out resistance due to the shear resistance between the top of the thread and the glulam. In order to quantify this performance, a theory of pull-out resistance of an embedded lagscrewbolt parallel to the grain direction was developed on the basis of Volkersen theory, which was originally developed for the shear stress analysis of rivet joints. The applicability of our theoretical approach was verified based on experimental results. Shear strength f_v and shear stiffness Γ, both necessary parameters of the theoretical formula, were determined by pull-out tests of thin 15-mm glulam specimens, assuming that in thin specimens the shear stress distribution would be almost uniform. Verification experiments were conducted using three kinds of Lagscrewbolts, with top thread diameters of 25, 30 and 35 mm, and the influence of various embedment depths ranging from 60 to 450 mm on the pull-out properties was examined. The developed theory predicted maximum pull-out load and slip modulus well.

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Gypsum-bonded particleboards overlaid with kenaf bast fiber mats on top and bottom surfaces were manufactured. The effects of the kenaf fiber overlay on the mechanical and dimensional properties of the boards were examined. The combustibility of various types of gypsum-bonded particleboards was examined.
The results are as follows:
1) Modulus of rupture (MOR) in the direction of kenaf fiber orientation in both dry and wet conditions, modulus of elasticity (MOE), and thickness swelling (TS) of gypsum-bonded particleboards were improved by the reinforcement with kenaf fiber mats.
2) The gypsum-bonded particleboards with particle/gypsum-dihydrate weight ratios less than 1/5 conformed to the standard requirements of quasi-noncombustible materials. Gypsum-bonded particleboards with a density greater than 0.8 g/cm³ reinforced with non-woven glass fabrics or kenaf fiber mats conformed to the standard for quasi-noncombustible materials.
3) Gypsum-bonded particleboards reinforced with non-woven glass fabrics or kenaf fiber mats could conform to the standard for noncombustible materials without a decrease in the bending properties of the boards.

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The properties of bark and wood of sugi (Cryptomeria japonica D. Don) as high bench culture media for strawberries were investigated. Three cultivars, “Toyonoka”, “Kentarou” and “HS-138” were cultured with sugi bark or wood beds. Yield, fruit weight and sugar content of strawberries were measured, and the results were compared with those using standard compost.
The yield of standard sizes with bark was 77% of the standard compost. The components and the water holding capacity of bark seemed to affect the yield. In the water extracts of the bark (bark : water ; 1 : 10, w/w), vanillic acid (4.7 mM), vanillin (0.1 mM), p-hydroxybenzoic acid (5.1 mM) and 3-hydroxy-4-methoxybenzaldehyde (0.6×10^-2 mM) were detected by GC-MS. These compounds indicated the inhibitory effects on the growth of komatsuna (Brassica campestris L. var. perviridis) in 0.5 mM.
The yield of strawberries with bark was lower than that with the standard compost even after curing in open air. When the medium was composed of two layers (upper layer : standard compost, lower layer : bark), the yield of strawberries was equal to that with the standard compost. As a result, high permeability and low water holding capacity of the bark would cause a decrease of water content of the medium and low yield of strawberries. The yield of standard sizes with wood stored in open-air was lower than that with green wood. It was considered that the water absorption and water holding ability were decreased by open-air storing. Therefore, the open-air stored wood had a tendency to lose its water easily and affected the growth of strawberries.
It was considered that the components of the bark would be decrease by watering during production of strawberries ; therefore, the water holding ability of bark and wood rather than their components would affect the yield of strawberries.

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We investigated the humidity control capacity of charcoals from wood carbonized at 500, 700 and 900°C. As an index of the capacity, we adopted the slope (B) of the linear equation approximating the relationship between logarithm of relative humidity and temperature in a closed steel box (volume : V = 0.0197 m³) containing charcoal (weight : W kg). The value of B of charcoal blocks was affected by the period of temperature change, while that of charcoal grains (5.5∼8.0 mm) was independent of the period and comparable to that of activated carbon or wood powder. There was no significant difference in the capacity between charcoals carbonized at 500 and 700°C. However, the capacity of charcoals carbonized at 900°C was slightly inferior to that of charcoals carbonized at 500 and 700°C. Charcoal capacity was much inferior to that of silica gels when used for humidity conditioning in repositories of museums below a W/V value of 0.5 kg/m³ as recommended by the silica gel maker. However, above a W/V value of 1.0 kg/m³, there is only a small difference in capacity between charcoal and silica gel. In silica gels, differences in wave shape of temperature changes had no recognizable effect on the value of B. The quantity of absorbed or desorbed moisture per unit weight of material was abruptly increased by decreasing W/V, especially in silica gels. However, at W/V greater than 1.5 kg/m³, it showed almost the same value of 1∼2 g/kg regardless of the material.

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Aldehydes and volatile organic compounds (VOCs) emission from plywood of various formaldehyde emission grades were measured using a small chamber method (JIS A 1901). The effect of the formaldehyde emission grade on emission of the other aldehydes and VOCs was discussed. Formaldehyde emission rates of F_????????_ grade plywood were determined to be below 5 μg/m²h by the small chamber method after 21 days. Formaldehyde emission from plywood greatly depended on the adhesives and wood species, and the emission of other aldehydes was not related to the formaldehyde emission grade. The formaldehyde scavenger used in this study had no reducing effect on the emission of aldehydes other than formaldehyde. The primary VOC emission from plywood was terpenes derived from the wood. The amount and variety of VOC emission from plywood depended on the wood species.

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