• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.38 no.2 s.115
• /
• pp.35-42
• /
• 2006

This study was carried out to develop a new application field of traditional Hanji and obtain the basic data for producing functional Hanji using sawdust ceramics and rice-husk ceramics as an architectural material. The results measuring water vapor permeance and water vapor absorption for using window materials and wallpapers are as follows. Hanji wallpaper has good things in controlling indoor space comfortably. Particularly, ability of controlling humidity of Hanji wallpaper affects indoor space comfort and human health. In the case indoor humidity is higher than outdoor humidity, according to the addition of ceramics, Hanji wallpapers maintain the humidity by retaining water vapor molecules in the pores of ceramics. Thus the Hanji wallpapers with ceramics, in particular rice-husk ceramics, make it superior to non-ceramics Hanji wallpapers in maintaining the humidity indoors.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2006.11a
• /
• pp.297-300
• /
• 2006

Various buildings constructed by environmentally friendly resources are being built in KOREA. Especially the building made by the wood, which has environmental characteristics that the reinforced concrete and brick doesn't have, are acknowledged with its superiority. Then, studies on indoor thermal control capability of the wooden building and influence of its indoor environment to sensory environment of occupants are not enough proceed. Thus, there were proceeded 24 hours measurements for indoor and outdoor thermal environmental elements of Log Cabins and the hourly subjective tests to evaluate indoor amenity of occupants in this study. The results of the study are following: 1) Upon evaluation on thermal environment elements, indoor and outdoor dry bulb temp were 22.0$^{\circ}C$ and -2.9$^{\circ}C$, and Indoor and outdoor average relative humidity were 25.8%and 52.7%. Differences of indoor and outdoor temperature and humidity were 24.9$^{\circ}C$ and 26.9%. 2) Upon contrastive analysis between the results of subjective tests, warm and cold sensation vote, and PMV (Predicted Mean Vote) and PPD (Predicted Percent Dissatisfaction), values of subjective tests W.9

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.3
• /
• pp.61-69
• /
• 2007

The building materials used for improving indoor air quality, the wood charcoal mixed with cement mortar or natural water paint were examined for their potential removing ability of formaldehyde. After the reaction of samples with formaldehyde in the glass flasks designed in our lab, the remaining formaldehyde was collected using DNPH (2,4-dinitrophenyl hydrazine) cartridges, and their concentration was determined using HPLC. From the results, it was found that the removing amount of formaldehyde per one gram sample containing 5, 10, or 15% of wood charcoal was more than three times compared to that of control (100% cement mortar or water paint). Their elimination percentages from the initial formaldehyde was about 80~90%. The experimental results for wood charcoal-water paint showed a similar trend with those of wood charcoal-cement mortar samples. Their elimination percentages from the initial formaldehyde was about 90%. It is proposed that formaldehyde is adsorbed on the adsorbed 'O' or 'OH' groups in the graphene layers formed through the re-arrangement of lignocellulose in the wood during the carbonization procedure.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.5
• /
• pp.24-37
• /
• 2007

The Korean Ministry of Environment started controlling indoor air quality (IAQ) in 2004 through the introduction of a law regulating the use of pollutant emitting building materials. The use of materials with formaldehyde emission levels above $1.25 mg/m^2{\cdot}h$ (JIS A 1901, small chamber method) has been prohibited. This level is equivalent to the $E_2$ grade ($>5.0mg/{\ell}$) of the desiccator method (JIS A 1460). However, the $20{\ell}$ small chamber method requires a 7-day test time to obtain the formaldehyde and volatile organic compound (VOC) emission results from solid building interior materials. As a approach to significantly reduce the test time, the field and laboratory emission cell (FLEC) has been proposed in Europe with a total test time less than one hour. This paper assesses the reproducibility of testing formaldehyde and TVOC emissions from wood-based composites such as medium density fiberboard (MDF), laminate flooring, and engineered flooring using three methods: desiccator, perforator and FLEC. According to the desiccator and perforator standards, the formaldehyde emission level of each flooring was ${\le}E_1$ grade. The formaldehyde emission of MDF was $3.48 mg/{\ell}$ by the desiccator method and 8.57 g/100 g by the perforator method. To determine the formaldehyde emission, the peak areas of each wood-based composite were calculated from aldehyde chromatograms obtained using the FLEC method. Formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and benzaldehyde were detected as aldehyde compounds. The experimental results indicated that MDF emitted chloroform, benzene, trichloroethylene, toluene, ethylbenzene, m,p-xy-lene, styrene, and o-xylene. MDF emitted significantly greater amounts of VOCs than the floorings did.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.3
• /
• pp.79-87
• /
• 2007

This study investigated the effects of lacquer-finishing to prevent discoloration of coloring chestnut wood coated with natural dyes from deteriorating factors such as lights (indoor, 500 lux and outdoor, 50,000~70,000 lux), acid, alkali, and heat through measurement of color difference. Lacquer-finishing coating contributed to protection of intrinsic color of the natural dyeing woods in spite of severe treatment. In particular, dyeing liquor with alkali pH played a great role in prevention of light discoloration.

• Fire Science and Engineering
• /
• v.29 no.4
• /
• pp.49-56
• /
• 2015

Toxic gases from five types of interior building materials were investigated according to Naval Engineering Standard (NES) 713. The materials were plywood, indoor wall coverings (wood wall plate members and pine wood), reinforced Styrofoam insulation, laminate flooring, and PVC. Specimens were measured using an NES 713 toxicity test apparatus to analyze the hazardous substances in combustion gas from the materials. We used the US Department of Defense standard (MIL-DTL, Military Standard) to calculate the toxicity index of the combustion gas. Emissions of $CO_2$ from all specimens did not exceed the NES 713 limit of 100,000 ppm. The amount of CO gas emissions from reinforced Styrofoam insulation was 6,098 ppm. 25 ppm and 49 ppm of formaldehyde were released from the reinforced Styrofoam insulation and PVC flooring, respectively. These values were less than the limit of 400 ppm. The highest emissions were from $NO_X$ emitted by plywood and were above the limit of 250 ppm. The toxicity index of the specimens were calculated as 5.19 for plywood, 4.13 for PVC flooring, 2.35 for reinforced Styrofoam insulation, 2.34 for laminate flooring, and 1.22 for indoor wall coverings (pine wood). Our research helps us to understand the properties of these five interior materials by analyzing the combustion gas and explaining the toxicity of constituents and the toxicity index. Also, it would be useful for giving fundamentals to guide the safe use of interior materials for applications.

• Journal of the Korean Wood Science and Technology
• /
• v.48 no.2
• /
• pp.217-230
• /
• 2020

Global warming has increased interest in reducing greenhouse gas emissions. And a policy has effort to reduce energy consumption as a greenhouse gas reduction plan. In Korea, 25% of total energy is consumed in the building sector. In order to reduce energy consumption of buildings, it is possible to expand the utilization of wood as a structural material or thermal insulation materials with low thermal conductivity. It is also reported that when used as an interior finishing material, the energy consumption of the building is reduced by up to 7% by insulation performance. In this study, the heat transfer characteristics and the heat capacity were compared according to the three type of finishing materials(cement, paulownia coreana, medium density fiberboard) normally used as indoor finish materials. Through this study, most of the heat transfer volumes are transferred in the form of radiant heat, and the result was derived from the highest amount of energy and heat transfer in the use of paulownia coreana. When indoor finishing materials are used as wood, it is deemed that energy efficiency inside the building will be improved.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.4
• /
• pp.357-366
• /
• 2014

Based on fundamental properties and machining characteristics of Yellow poplar (Liriodendron tulipifera L.), it has well performance on machinability or workability, drying, and fine surface. Additionally, yellow poplar is light weight and has bright color with high performance of bending processing, so it could be used for furniture or artworks materials and wood-based panel materials. Recently, public attention has been focused on indoor air quality, and Ministry of environment drift more tight regulation on indoor air quality for an apartment house and public facility with the times. Construction materials has been assessed emission of volatile organic compounds (VOCs) and formaldehyde according to law (No.10789), so yellow poplar is also needed to assess these emission characteristics. Emission of VOC and aldehyde compounds from dry and green wood condition of yellow poplar were investigated with KS M 1998:2009. Based on results, more than 30 compounds were detected from yellow poplar, and lower NVOC (natural VOC) were emitted than AVOC (Anthropogenic VOC) and OVOC (other VOC). Formaldehyde emission was lower than $5{\mu}g/m^3$ and acetaldehyde, ketone, and propionaldehyde were detected from yellow poplar. From dry yellow poplar, m-Tolualdehyde ($33.6{\mu}g/m^3$) was additionally detected while no detection of propionaldehyde. After drying process, amount of ketone emission increased significantly. The unique smell of yellow poplar may not only come from emission of acetaldehyde and propionaldehyde.

• Journal of the Korean Wood Science and Technology
• /
• v.38 no.6
• /
• pp.518-525
• /
• 2010

Infrared (IR) thermography which is the technique for detecting invisible infrared light emitted by objects due to their surface thermal condition and for producing an image of the light has been applied in various field without damaging the objects. It also could be used indirectly to examine the inside of an object. In this study, insulation property of wooden house in Korea Forest Research Institute (KFRI) was evaluated with according to "Thermal performance of building - Quantitative detection of thermal irregularities in building envelopes - infrared method (KS F 2829)". This method uses "Temperature Difference Ratio (TDR)" between outdoor wall surface and indoor wall surface of wooden building for evaluating its thermal performance. The thermal performance of a room on the 2nd floor of the wooden house was focused in this study and IR thermography on the indoor and outdoor surface of the house was captured by IR camera. Heat loss from the corner and the window of the wooden house as well as wall of the house was quantitatively evaluated and the invisible heat loss in the wall was detected. It is expected that the results from this study could contribute to improve the wooden building energy efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.9
• /
• pp.1847-1853
• /
• 2011

Analysis of an indoor propagation channel has conventionally used the ray-tracing method. But, in this paper, we had modelling the channel for three dimensional indoor structure by the finite difference time domain method for three dimensional full wave analysis. An excitation signal of the FDTD method used plane wave. The plane wave was excited using the total field/scattered field method. And absorbing boundary condition used the perfectly matched layer method with 7 layers. An living room for the simulation of indoor channel modeling is surrounded the wall that be composed of the wood, the conductor, the glass and concrete. When there are furniture in the living room or not, it were simulated, respectively. As simulation results, we could identify the fading effect of multipath at indoor propagation environment, calculated mean excess delay and rms delay spread for the receiver design.