• Steel and Composite Structures
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• v.13 no.5
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• pp.489-500
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• 2012

Cold-formed steel profile sheets acting as decks have been popularly used in composite slab systems in steel structural works, since it acts as a working platform as well as formwork for concreting during construction stage and also as tension reinforcement for the concrete slab during service. In developing countries like India, this system of flooring is being increasingly used due to the innate advantage of these systems. Three modes of failure have been identified in composite slab such as flexural, vertical shear and longitudinal shear failure. Longitudinal shear failure is the one which is difficult to predict theoretically and therefore experimental methods suggested by Eurocode 4 (EC 4) of four point bending test is in practice throughout world. This paper presents such an experimental investigation on embossed profile sheet acting as a composite deck where in the longitudinal shear bond characteristics values are evaluated. Two stages, brittle and ductile phases were observed during the tests. The cyclic load appears to less effect on the ultimate shear strength of the composite slab.

• Journal of the Korean housing association
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• v.21 no.3
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• pp.67-76
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• 2010

The purposes of this study are to understand residents' needs in regard to living space and to suggest how to provide layout options for the infill, based on their needs, so that the residents can change their living space to suit their own need. This study analyzed residents' needs in terms of living spaces through literature reviews on apartment remodeling and related previous studies. The results are as follows: First, the residents remodeled the various infill, and remodeling works are then classified into five infill groups according to the flexible features: 1) structural elements, such as flooring, ceilings, interior walls, and windows/doors; 2) equipment elements, such as lighting and electricity, electrical wiring, heating arrangements, and water supply & drainage systems: 3) finishing material elements, such as finishing materials for floors, walls, and ceilings, skirting boards, moldings, and art walls; 4) furniture elements, such as built-in wardrobes, storage closets, and kitchen cabinets; and 5) bathroom facility elements such as faucets and sinks. Second, based on the remodeling features, four ways to provide options can be suggested. 1) options are provided for each room; 2) options are provided in connection with structural elements; 3) options are provided for each finishing material element; and 4) options are provided with the combinations of different bathroom facilities.

• KIEAE Journal
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• v.9 no.2
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• pp.59-64
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• 2009

The senior citizens population and welfare institution for them is increased. The senior citizens in welfare institution spend a long time in indoor and their health is greatly affected by the indoor environment. Therefore, the indoor environment of senior citizens welfare institution is very important. This study presents some primary data based on the survey of architectural conditions and the measurements of indoor air quality for senior citizens welfare institution. According to characteristic of region, six of Incheon Area's senior citizens public welfare institution are selected. An investigation and analysis into architectural conditions and indoor air quality including temperature, humidity, CO, $CO_2$, PM10, HCHO, TVOC are conducted. The temperature, humidity and $CO_2$ concentration is some high. The HCHO concentration is very high. The indoor flooring and furniture materials highly impacts on the concentration of HCHO and TVOC.

• Journal of KSNVE
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• v.9 no.3
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• pp.477-484
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• 1999

This study aims to present proper thickness of resilient mount and pattern of chips for the improvement of impact sound isolation. To achieve this aim, field tests were performed to evaluate the performance of impact sound isolation of pilot samples using waste tire chips against light and heavy-weight impacter, which samples were installed over concrete slabs of an apartment housing. In this study, the experiments were performed by the impact sound level of floors in KS F 2810 "Method for field measurement of floor impact level". As results, a flooring structure using waste tire chips as a resilient mount, with no relation to chip's types, has enhanced performance by 1~2 degree in light impact sound isolation, while it has improvement in heavy impact sound isolation. And fiber-type chips have better performance than granule-type ones when they overlaid concrete slab with 15~20 mm of thickness. For the improvement of impact sound isolation, it is recommended that insulating materials should be applied at joints between floating floors and walls, or floating floors and a doorframes, and also waterproof papers should be used for the effective thickness of resilient mount.ent mount.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.13-20
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• 2005

This paper deals with flexural vibration techniques as a means of predicting bending strength properties for quarter-sawn and flat-sawn planes of red pine containing knots. Dynamic modulus of elasticity $(MOE_d)$ was calculated from resonance frequency obtained from the flexural vibration induced by a magnetic driver in quarter-sawn and flat-sawn planes of red pine containing knots. The dynamic MOE were well correlated to bending strength properties. Their correlation coefficients ranged from 0.866 to 0.800 for the regression between dynamic MOE and static bending MOE or MOR. The difference of the values between quarter-sawn and flat-sawn was very small. These values were higher than correlation between percentage of total knot diameter to total width of red pine specimen $(K_T(%))$ as well as $K_O(%)$ base upon ASTM D 3737 and static bending strength properties (correlation coefficient r = 0.448~0.704), and were similar to those between static bending MOE and bending MOR (r = 0.850). These results indicate that dynamic MOE obtained from resonance frequency induced by flexural vibration of magnetic driver is able to effectively use for predicting of static bending strength of red pine containing knots as well as static MOE.

• Journal of Korean Society of Forest Science
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• v.98 no.2
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• pp.203-211
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• 2009

The study was conducted to examine consumers' awareness and perceptions on forest certification and their willingness to buy and pay price premium for certified wood products especially for selected four wood products. A total of 136 residents in Seoul and Gyeonggi Province were interviewed in the autumn of 2008. Although only 24.3 percent of the consumers are aware of forest certification, 82.4 percent of the respondents recognized the need and significance of forest certification. In general, 77.2 percent of the respondents were willing to buy certified wood products. Majority of the respondents, 84 out of 136 respondents (61.8%) expressed their willingness to pay (WTP) from more than 0 percent to less than 10 percent. Consumers' average WTP for certified wood products was estimated to be 5.6 percent. From the results of the study, lower priced wood products, such as copier paper (WTP=9.8%) and wood frame (WTP=11.6%), have higher price premiums than high priced products, such as wood table (WTP=6.8%) and wood flooring (WTP=7.6%). In conclusion, there could be feasible markets for certified wood products in South Korea as four out of five consumer are willing to pay more for such products. For the forest certification system to be adopted and widely accepted, the perceptions of forest stakeholders including consumers should be further increased.

• Journal of the Korean Wood Science and Technology
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• v.23 no.2
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• pp.77-82
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• 1995

With the aim to utilize pine wood(Pinus densiflora Sieb. et Zucc.) as an interior building materials, such as flooring material, monoethylene glycol(MEG) resin solution was impregnated into greenwood. Specimens of three different qualities, that is, normal wood, resinous wood and compression wood, were prepared. Distribution of resin element(phosphorus) in MEG resin solution-impregnated woods and preservative effectiveness against brown rot fungi(Tyromyces palustris and Serpula lacrymans) of these woods were investigated. The results were as follows: 1. The concentration of phosphorus into cell walls of resinous wood and compression wood was lower compared to that of normal wood. This shows that the quality of wood has an influence on the penetration of MEG resin solution into the wood. It was shown from a leaching test that MEG resin could be leached out easily from the cell walls. 2. The resinous wood and compression wood, even without MEG resin solution impregnation had high decay resistance. For normal wood, significant improvement of preservative effectiveness was observed after impregnation of MEG resin solution. It was shown that MEG resin was leached out from the woods after leaching test, resulting in the reduction of preservative effectiveness. From this result, suitability of MEG resin solution-impregnated woods as an interior materials was recognized.

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.440-450
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• 2009

In case of wood flooring, the high emissivity would be one of the most important properties especially as the cover material of underfloor heating system. The FIR (Far Infrared) materials such as wood emit FIR energy by heating, which has been used as the medical therapy such as dry sauna. This research investigated the emissivity and the emission power of wood composites by comparing the amount of the three heat transfer modes transferred by infrared radiation which came from the increased temperature of the bottom board of the plywood box by the heater. The results showed the value of radiation mode was the highest mode for the plywood box, and the convection mode was the main mode for the aluminum box. The rate of convection was 81.8% in the aluminum box and 48.2% in the plywood box, respectively. In case of the rate of radiation, the aluminum box showed only 15.4% and the plywood box showed 51%. The emissivity and the emission power of birch plywood showed the same values as those of wood. The amount of energy required for the temperature rising of water within vial in the aluminum box and in the plywood box were 3.32 kJ and 6.70 kJ respectively, which showed that the vial temperature of the plywood box was two times higher than that of the aluminum box.

• Journal of the Korea Furniture Society
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• v.22 no.3
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• pp.219-229
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• 2011

Sick building syndrome symptoms that are experienced by building occupants may be caused by toxic substances such as formaldehyde and VOCs, which are known to be emitted from building materials and wood composite products such as wood-based panel, furniture, engineered flooring and construction adhesive. In Korea, the use of wood composite products for indoor environments has increased over the last decade. Recently, wood composite products have been installed in approximately 95% of newly constructed residential buildings. The use of these products has resulted in problems related to human health, and consequently a realization about the importance of indoor air quality. In addition, consumer demand is increasing for natural materials because conventional building materials and wood composite products are made by adding urea-formaldehyde resin or they contain formaldehyde-based resin. More recently, many efforts have been made to reduce formaldehyde emission from building materials that laid in the indoor environment. Especially, if conventional formaldehyde-based adhesives are replaced with green adhesives for residential spaces, it is possible to reduce most of the emission amounts of formaldehyde in indoor environments. In line with this expectation, many researches are being conducted using natural materials such as tannin and cashew nut shell liquid (CNSL). This study discussed the affects and possibilities of green adhesives to reduce formaldehyde emission in indoor environments.

• Physical Therapy Korea
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• v.14 no.2
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• pp.85-90
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• 2007

In many manufacturing occupations, industrial workers reported foot or lower leg problems such as discomfort, pain or orthopedic deformities. This study investigated the effects of two different working conditions upon assembly worker's perception of discomfort and foot pain associated with various body parts. Twenty-three male volunteers performed work in the factory. Ergonomic intervention has been to modify the flooring in an attempt to alleviate the problems associated with constrained standing and walking work. The worker's standing conditions consisted of standing on a hard floor while wearing shoe insoles. Questions were asked regarding body discomfort and foot pain. Significant differences in body discomfort and foot pain were found when comparing the overall effects of wearing shoe insoles on a hard floor (p<.05). This investigation indicated that shoe insoles reduced body discomfort and foot pain (p<.05).