• Journal of Conservation Science
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• v.36 no.6
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• pp.505-510
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• 2020

In this study, the anti-stain effect of the Traditional Myoung-oil, which has been reproduced through traditional method, the Clean Myoung-oil, which was developed in an eco-friendly method through scientific analysis of Traditional Myoung-oil, and the perilla oil, which is the raw material of Myoung-oil and is currently used as a finishing agent when repairing wooden cultural properties was evaluated. As a result of the evaluation, perilla oil showed almost no anti-stain effect, whereas both types of Myoung-oil showed high anti-stain effect. However, it was confirmed that the anti-stain effect was significantly reduced after 4 weeks of exposure to the strain when Myoung-oil was diluted with terpene oil, a natural solvent. Thus, it was considered that the amount of treatment in the wood affected the anti-stain effect of Myoung-oil. In other words, in constructing wooden buildings, Myoung-o il is more suitable as a finishing agent to suppress mold growth than perilla oil. And, in order to increase the applicability of Myoung-oil, it is suggested that additional research on the optimal treatment amount and treatment method that can inhibit mold growth inhibition in outdoor environments is necessary.

• Journal of Korean Society of Forest Science
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• v.96 no.4
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• pp.432-437
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• 2007

The purpose of this study was to select regional distinctive Non-Timber Forest Products (NTFP) in Gangwon Inland Mountains Area. It was considered as NTFP Pine mushroom, Raw Oak Mushroom, Chestnut, Pinenut, Acorn, Resin, Cultivated Mountain Ginseng, Fernbrake, Chinese bellflower, Lance asiabell, Angelica, Aster scaber, Sap, Wood Vinegar. Regional weight, item weight and forest products quotient were used for the selection of NTFP. Forest products quotient was an application of Location Quotient that is used Input-Output analysis. As a result, Chestnut was selected in Chuncheon. Raw Oak Mushroom was selected in Wonju and Pyeongchang. It was selected Pinenut in Hongcheon, Lance asiabell in Hoengseong and Hwacheon, Acorn in Cheorwon, Aster scaber in Yanggu and Sap in Inje.

• Journal of the Korean Wood Science and Technology
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• v.51 no.5
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• pp.419-430
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• 2023

In this study, the floor impact sound insulation performance of Korean domestic Cross-Laminated Timber (CLT) slabs was evaluated according to their joint types, species and thicknesses in laboratory experiments. The sound insulation performance of the CLT has not been investigated before, thus, this study was conducted to quantify basic data on floor impact sound insulation performance of CLT slabs. 5-ply and 150 mm thick CLT panels made of 2 species, Larix kaempferi and Pinus densiflora, were used for the study. The CLT panels were assembled by 3 types of inter-panel joints to form floor slabs: spline, butt and half-lap. And the 150 mm thick Larix CLT slabs were stacked to the thicknesses of 300 mm and 450 mm. The heavy-weight floor impact sound insulation performance of the 150 mm CLT slabs were evaluated to be 70 dB for the Larix slabs and 71.6 dB for the Pinus slabs, and the light-weight floor impact sound insulation performance, 78.3 dB and 79.6 dB, respectively. No significant difference in the sound insulation performance was found between the slabs of the 2 species or among the 3 types of joints. The reduction of 1 dB in the heavy-weight floor impact sound and 1.6 dB in the light-weight floor impact sound per 30 mm increase in thickness were confirmed through the experiments. This study can be viewed as the basic research for the evaluation of floor impact sound insulation performance of CLT.

• Steel and Composite Structures
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• v.50 no.6
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• pp.689-703
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• 2024

Construction of high-rise structures, formwork systems that can be installed quickly, resistant to external loads, can be used more than once, have become a necessity. Timber and composite timber materials are preferred in the formation of such formwork systems due to their durability, ease of assembly, light weight and easy to use more than one time. Formwork beams are the most commonly used structural component in the formation of such formwork systems, and these beams can be damaged for different reasons during their lifetime. In this study, H20 top P type timber formwork beams with 1800 and 2450 mm length which is among the products of DOKA(c) company is damaged under the effect of static loading up to a high load level of 85% of the maximum ultimate capacity and after being retrofitted using anchored CFRP strips, performance and behavior of the beams under the influence of various loading types such as static, fatigue and impact are investigated experimentally. Two different lengths of retrofitted timber formwork beams were tested by applying monotonic static, fatigue and impact loading and comments were made about the effects of the retrofit method on performance under different loading types.

• Journal of Forest and Environmental Science
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• v.39 no.3
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• pp.155-166
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• 2023

Consumption and selling of Non Timber Forest Products (NTFPs) are important means to meet nutritional requirements and improve the socio-economic conditions of the rural population. The purpose of this study was to document the status and utilization pattern and assess the economic value of NTFPs sold in the markets of the Itanagar Capital Region (ICR) of Arunachal Pradesh. Five major markets with 182 vendors were surveyed, and a total of 94 plant-based products under 63 species belonging to 32 families were found to be sold in the markets. Species like Acmella oleracea, Clerodendrum glandulosum, Dioscorea alata, Houttuynia cordata, Phoebe goalparensis, Piper pedicellatum, Zanthoxylum rhetsa, etc. are found to be highly preferred and have a higher demand in the local markets. The edible products of species like Piper pedicellatum and Phoebe goalparensis though highly consumed in the study area, are used only within the region, and the national and international demands of the species are nil. The animal-base products are not included in the study.

• Journal of the Korean Wood Science and Technology
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• v.34 no.5
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• pp.19-28
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• 2006

There has been considerable research in recent times in light-timber med structures in fires. These structures have included horizontal (floor-like) panels in bending and walls under eccentric and approximately concentric vertical loading. It has been shown that compression properties are the most dominant mechanical properties in affecting structural response of these structures in fire. Compression properties have been obtained by various means as functions of one variable only, temperature. It has always been expected that compression properties would be significantly affected by moisture and stress, as well. However, these variables have been largely ignored to simplify the complex problem of predicting the response of light-timber framed structures in fire. Full-scale experiments on both the panels and walls have demonstrated the high level of significance of moisture and stress for a limited range of conditions. Described in this paper is an overview of these conditions and experiments undertaken to obtain compression properties as a functions of moisture, stress and temperature. The experiments limited temperatures to $20{\sim}100^{\circ}C$. At higher temperatures moisture vaporizes and moisture and stress are less significant. Described also is a creep model for wood at high temperatures.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.231-241
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• 2009

Trade specialization index, import market share, unit value index, market comparative advantage index have been applied to compare the competitiveness of forest products in Korean and European markets for the case of Korea-EU FTA. The results say that no items of non-timber products would show a surge of imports as a result of FTA. Timber products, however, such as non-coniferous plywood, continuously shaped wood (non-coniferous), densified wood, wood wool and flour, other (plywood), other (particle board, 441039)), other (fiberboard), oriented strand board (other), other (particle board, 441090), other (particle board, 441031), Prefabricated buildings of wood, fibreboard (of a density exceeding $0.5g/cm^3$ but not exceeding $0.8g/cm^3$), wooden frames (for paintings, photographs, mirrors or similar objects) and wood marquetry and inlaid wood are expected to increase of their imports by eliminating tariffs. For Korean exports no items of non-timber products have competitiveness in European market. For Korean pyroligneous liquid, which is the only competitive timber product in EU market in terms of MCA and TSI, it is difficult to decide whether it has competitiveness, since the actual exports have taken place occasionally during a period of last five years.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.682-690
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• 2015

The bonding performance of two types of wood adhesives, namely phenol-resorcinol-formaldehyde (PRF) resin and melamine-urea-formaldehyde (MUF) resin for glued laminated timber manufactured by high frequency (HF) heating was evaluated. The HF heating system consists of HF oscillator with dielectric heating system for curing adhesives, and hydraulic press system for clamping glued laminated timber. The designed frequency and output power of the HF system was as 5 MHz and 60 kW, respectively. To verify dielectric heating mechanism under HF oscillation, the heat loss factors of laminae and adhesives were measured. The results show that it is possible to selectively heat adhesives for their curing due to the remarkably higher loss factor of the adhesives than those of wood laminae. The temperature of adhesive in the bonding line reached up to the set temperature within a few seconds by high frequency oscillating, which advanced the curing of adhesive afterwards. The bonding performance, such as shear strength of bonding line, water soaking delamination, and boiling water soaking delamination of PRF resin met the requirement of Korean Standard (KS), however the MUF resin did not meet the KS requirement of boiling water soaking delamination. These results indicate that the HF heating system is successful to manufacture glued laminated timbers with PRF resins to meet the bonding requirements.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.8
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• pp.129-136
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• 2018

Termites are important sub-baits of natural ecosystems and are beneficial insects that are natural decomposer. However, the building materials used by human beings can not coexist with each other on timber which is a termite food. As of 2017, due to fertile forests, warming, and the spread of boilers, termite damage to timber construction is increasingly occurring day by day. Currently, Korea utilizes fumigation, Beit system, preserved wood, etc. of chemical products as termite control measures. But in the case of control measures, timber that has already been eaten by termites can not serve as a structural material and must be repaired. On the other hand, in the case of overseas, Scale of damage to termites the influence on the construction is also large, and a lot of research has been carried out on the prevention methods. In this thesis, investigate such foreign control measures, Would like to suggest a suitable method for Korea.

• Journal of the Korea Furniture Society
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• v.23 no.4
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• pp.460-466
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• 2012

This study was conducted to investigate the surface hardness of thermally-compressed larch wood by compression set and temperature. The surface hardness of thermally-compressed larch wood increased with increasing compression set and temperature. For compression set 60%, the specific gravity was increased as 0.93. However, the surface hardness was lower value as 31.1 N/$mm^2$ compared with a similar specific gravity of the tropical timber. For density profile, less than compression set 40%, compression was observed mainly surface area. On the other hand, more than 50%, density profile variation was reduced by compression of central part. Results of this study indicate that thermally-compressed larch wood can be replace some imported hardwoods such as oak or cherry. However, thermally-compressed larch wood was difficult to replace the tropical timber being imported in terms of surface hardness.