• Journal of the Korean Wood Science and Technology
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• v.31 no.3
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• pp.50-60
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• 2003

The main purpose of this study was to propose the development direction and application method of wood as a landscape material by analysis and investigation of the present condition and characteristics of wood, which is a quite interesting natural material for its beauty as an exterior material. This study is based on the relationships between the establishment of development direction and practical use of exterior wood as a landscape material. The research method used was fieldwork and data analysis. On the analysis of the present condition of wood utilization, it was investigated to need of complement of a design aspect, use method, the limit of use type, and use range. The direction of a durable design for the practical use of exterior wood as landscape materials was established. On the use of exterior wood, first, the characteristics of wood have to be understood. Then exterior wood can be used while preserving its safety and beauty over a long time by physical and chemical treatment. At the same time, an application plan for the practical and effective use of wood as an outdoor landscape material, we concluded that future research in design aspects is needed in consideration of physical, chemical, and structural properties of durable wood materials used in outdoor facilities.

• KIEAE Journal
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• v.6 no.4
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• pp.33-39
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• 2006

This study aims to investigate the method to reduce the surface temperature caused by insolation. To achieve this goal, surface temperature of building is measured and the effects of exterior material's color and brilliance were checked with infrared imaging. And also, exterior material's absorptances due to outdoor surface heat transfer coefficients were measured. After surface temperature measurement of 37 specimen of 5 categories, the temperature is the highest on wood($53.62^{\circ}C$) and panel($52.05^{\circ}C$). Dryvit, stone, brick is the rating of order. For exterior material's absorptances, panel(0.883) and wood(0.868) were high and Dryvit, stone, brick follows wood and panel.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.264-273
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• 2016

The insulation of a building envelope influences the hygrothermal performance as well as the thermal performance of the building. While most of Korean wood frame houses have an interior insulation system, the exterior insulation system with high thermal performance has recently been applied. While it can be effective in energy savings for better insulation performance, without consideration of the moisture, condensation and mould growth can occur. Therefore, in this study, hygrothermal behaviour, water content, and mould growth were analyzed using hygrothermal simulation of an exterior wall of a wood frame house with which the interior insulation and exterior insulation systems were applied. The wall layer included Wall A (Interior insulation) and Wall B (Exterior insulation). The U-values were identified as 0.173 and $0.157W/m^2K$, respectively. The total water content and OSB absolute water content of Wall A were confirmed to be higher than those of Wall B, but the absolute water content did not exceed the reference value of 20%. The moisture content of the two walls was determined to be stable in the selected areas. However, mould growth risk analysis confirmed that both Wall A and Wall B were at risk of mould growth. It was confirmed that as the indoor setting temperature decreased, the mould index and growth rate in the same area increased. Therefore, the mould growth risk was affected more by indoor and outdoor climate conditions than by the position of the insulation. Consequently, the thermal performance of Wall B was superior to that of Wall A but the hygrothermal performances were confirmed to be similar.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.118-119
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• 2019

The exterior finish not only has a relationship to the functionality of building, but also the spatial aesthetics and visual perception. Common exterior finishes are wood, stone or acrylic based and etc. However, these finishes have different attributes which can alter the quality of the architecture, such as durability, moisture and fire resistance. To make up for the short-comings of these materials, we have used iron based resources for optimization. However, iron materials are expensive, so they have limitations in general use. In this study, we have experimented with various forms of exterior finishes using cement, which is the most efficient and widely used building material with several economic advantages. We experimented with different materials to use as the formwork for the gloss of the cement matrix. As a result, the gloss show that order of urethane, steel, and wood material.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.409-418
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• 2017

This work attempted to manufacture glued-laminated timber (Glulam) bonded with melamine-urea-formaldehyde (MUF) resin adhesives at various melamine contents from 20% to 50% under high frequency (HF) heating for a very short time. Two preparation methods were employed to prepare MUF resin adhesives with different melamine contents: one-batch method of synthesizing MUF resins in a single batch, and two-batch method of mixing urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized separately. As the melamine content increased, the gelation time and peak temperature of MUF resins decreased. The adhesion performance of plywood showed that the one-batch MUF resin adhesive with 50% melamine content only satisfied the standard requirement of water resistance. Thus, the one-batch MUF resin adhesive with 50% melamine content was applied for bonding wood lamina from four softwood species such as Japanese larch, Korean red pine, Korean pine and Japanese cedar to manufacture Glulam under HF heating. All Glulam samples bonded with the one-batch MUF resin adhesives with 50% melamine content except those from Korean Red Pine satisfied the requirement in water soaking or boiling water delamination test as an exterior grade Glulam. The presence of rosin in Korean Red Pine was believed to be responsible for its poor adhesion. These results showed that the one-batch MUF resin adhesives with 50% melamine content provided acceptable water resistance with exterior grade Glulam manufactured under HF heating.

• Journal of the Korean Wood Science and Technology
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• v.20 no.1
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• pp.15-22
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• 1992

This study was performed to investigate the corrosion of metal fasteners in waterborne preservative-treated wood. Of all the metal tested, steel exhibited the greatest amount of corrosion across all preservatives and exposure conditions whereas stainless steel was totally inert. Galvanized steel corroded at a much lower rate compared to steel and the corrosion of brass was negligible. Among the preservatives, CCA-Type B was the most corrosive system tested. The sequence for the average corrosivity across all metals was: CCA-type B>CCA-Type C${\geq}$ACC${\geq}$CCA-Type A. Across all metals and retentions the salt formulations were more corrosive than the oxide and the corrosion was increased with the increse in the amount of preservative loadings. The amount of corrosion was also increased with the increase in exposure relative humidity (RH) across all metals and presevatives However, at the 60% RH exposure condition, the corrosion of metals was very negligible. Consequently, it can be concluded that across all metals oxide-type preservatives should be used to prevent the corrosion problem of metal fasteners in contact with treated wood and the use of steel nail preservative-treated wood should be avoided without distinction of end-use location, i.e., exterior or interior, and the use of stainless steel or at least brass nail in damp exterior condition was strongly recommended.

• Journal of the Korean Wood Science and Technology
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• v.39 no.2
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• pp.179-186
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• 2011

In an effort to understand the hydrolytic degradation process of cured urea-formaldehyde (UF) resins responsible for the formaldehyde emission of wood-based composite panels, this study analyzed the influence of acid hydrolysis on the morphology of cured UF resins with different formaldehyde/urea (F/U) mole ratios such as 1.6, 1.4, 1.2 and 1.0. Field emission-scanning electron microscopy (FE-SEM) was employed to observe both exterior and fracture surfaces on thin films of cured UF resins before and after the etching with hydrochloric acid as a simulation of the hydrolytic degradation process. FE-SEM images showed that the exterior surface of cured UF resin with the F/U mole ratio of 1.0 had spherical structures after the acid hydrolysis while the other cured UF resins were not the case. However, the fracture surface observation showed that all the samples possessed spherical structures in the cured state of UF resins although their occurrence and size decreased as the F/U mole ratio increased. For the first time, we found the spherical structures in cured UF resins of higher F/U mole ratio of 1.4. After the acid hydrolysis, the spherical structures became a much predominant at the fracture surface. These results indicated that the spherical structures in cured UF resinswere much more resistant to the hydrolytic degradation by the acid than amorphous region.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.449-470
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• 2018

A review of research trends on wood surface protection for exterior use obtained the following conclusions: It has been reported that inorganic compounds such as chrome and copper used as wood preservatives can protect wood from weathering. It has been shown that precoating with hydrophobic substances such as wax and oil, UV absorbers, and HALS (Hindered Amine Light Stabilizers) enhances weathering resistance on the surface of ACQ-treated wood. Opaque coatings of paint/stains and semitransparent stains on the surface of preservative treated wood can increase the synergistic effects on prevention of weathering deterioration. Also the need for repainting periodically for the protection of the preservative treated wood surface has also been suggested. ZnO or $TiO_2$ of fine particles, metal ions such as Co, Cr, Fe, Mn, Ni and Ti, and UV absorbers such as tris-resorcinol triazine derivatives, triazine and benzotriazole were introduced as additives for preventing UV in the transparent coating on wood. Several reports showed that chemical modification such as methylation, acetylation, or alkylations have made some increases the effects of preventing weathering with the increasing weight gain of chemical formulas. In heat-treated wood, there were various contradictory reports on the resistance of weathering, and there were some other reports emphasizing the necessity of painting with UV resistance, which leads to the necessity of more advanced studies.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.465-469
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• 2010

In order to develop effective recycling technologies of disused railway wood ties, wood properties and residual creosote oil of wood ties were investigated. Among the total 50 wood ties, 32 wood ties were identified as tropical hardwood tree, such as, Keruing (Dipterocarpus spp.), Kempas (Koompassia malaccensis), Kapur (Dryobalanops spp.) Naytoh (Palaquium rostratum), and so on. Disused wood ties showed mostly sound structure without degradation of cell walls by decay fungi. Disused wood ties showed high strengths of bending and compressive parallel to grain because degradation of wood properties was hardly occurred in use under exterior condition. Disused railway wood ties had relatively poor depth of penetration and residual of creosote oil because of refractory wood structures. These results suggest that disused railway wood ties may be useful as recycling wood wastes.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.9-14
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• 1993

Weathering of wood in a region of acid rain was performed by the test which thin veneers of Sitka spruce were exposed to outdoor weathering for a total of 18 weeks, with a daily soaking for 30 minutes in acidified water in the pH range 2~5.6. The weathering measured by weight loss and loss in maximum failure load in tension was accelerated by the increase in the acidity of acidified water and in the period of outdoor exposure. It was also shown that the weathering was accelerated even with low acidic conditions in the case of long exposure period, although the weathering was rapidly accelerated with high acidic conditions. When compared the degree of weight loss with that of loss in failure load by weathering, the latter was much greater. From the results of this research, it could be concluded that at pH 4.0 or below of precipitation, the acceleration of weathering of exterior wood would become serious problems, which would be caused deterioration in performance of exterior wood.