• Advances in concrete construction
• /
• 제15권2호
• /
• pp.75-84
• /
• 2023

Currently, polymer matrix nanocomposites (PMCs) are a prominent area of research due to their outstanding mechanical, thermal, and durability properties. The increase in recent studies justifies the possibility of using PMCs in structural retrofitting and reconstruction of damaged infrastructure and serving as new structural material. Using nanotechnology, nanocomposite panels in flooring combine concrete and steel, providing a very high level of performance. In sports flooring, high-performance concrete has become a challenge for reducing sports injuries and refinement in rehabilitation. As a composite material, this type of resistant concrete is one of the most durable and complex multi-phase materials. This article uses polyvinyl alcohol polymer (PVC) and multi-walled carbon nanotubes as concrete matrix fillers. Solution methods have been used for dispersing PVC and carbon nanotubes in concrete. The water-cement ratio, carbon nanotube weight ratio, and heat treatment parameters influenced the concrete nanocomposite's tensile and compressive strength. The dispersion of carbon nanotubes in cement paste and the observation of nano-microcracks in concrete was evaluated by scanning electron microscope (SEM).

• 한국대기환경학회지
• /
• 제25권1호
• /
• pp.38-45
• /
• 2009

Since the seventies and the oil crisis, energy-saving measures have led to a reduction in the ventilation of room. The use of synthetic materials which emit various chemical substances had led to an increase in the concentration of indoor pollutants. "Sick building syndrome (SBS)" and "Sick house syndrome (SHS)" are worldwide problems. Also, the number of complaints about indoor air pollution caused by VOCs (Volatile organic compound) and HCHO (Formaldehyde) has increased. It is important that evaluating and understanding emission of indoor air pollutant from building materials. The object of this study was to evaluate emission test method for flooring such as wood based flooring, carpet tile, rubber tile, PVC sheet and tile, and to determine emission of TVOC and form-aldehyde. The quantity of TVOC and carbonyl compounds emission were sampled and measured by Tenax TA and gas chromatography/mass spectrometry (GC/MSD), 2,4-DNPH cartrige with ozone scrubber and high performance liquid from flooring. The TVOC concentration emitted from carpet tile was ($7.419\;mg/m^2 h$) the highest among 5 groups of test materials. In wood based flooring and PVC tile, the emitted concentration of toluene was high. And the dodecane emission was highest in carpet. The concentration of TVOC decreased by an increase in emission test period. After 7 days, the concentration of TVOC from floorings were about 50% below of the concentration at the first day. TVOC emission from wood based flooring, carpet tile, rubber tile, PVC sheet and tile were decreased in 28 days and remained steady after about 15 days. The concentration of formaldehyde emission from floorings showed extremely low.

• 한국주거학회논문집
• /
• 제25권2호
• /
• pp.19-26
• /
• 2014

The number of elderly who wants to access to Nursing Homes (NH) will increase due to the rapid aging society and domestic changes. Those who move into NH expect 24/7 care service in safe environment. Providing space free from danger, especially from fall, for the frail elderly is essential. The purpose of this study is to categorize performance needs of flooring materials in the aspect of safety, and analyze materials so that adequate ones for each space in NH can be suggested. Performance needs are as follows; slip resistance (dry/wet), fire resistance, resilience, water resistance, soil retardant, anti-bacterial, gloss, sound absorbtion. maintenance, durability, ease replacement, color and pattern variety, visual and tactual texture, tactile warmth, IAQ, sustainable material (before use), impact to nature (after use). They are categorized under function, economy, sensibility and sustainability. It was found that there are better materials than common ones that has been used repeatedly in NHs, such as vinyl sheets and VCT. In overall, Cork flooring and nylon carpet met all four categories, followed by wool carpet, rubber and linoleum. For bedroom, wood flooring, Cork, rubber, wool carpet, nylon carpets were suggested. In bathroom with shower, rubber, vinyl sheet and porcelain tiles were safe materials. As living/dining room and corridor floors, wool carpet, nylon carpet, cork flooring would be excellent as they are resilient and durable. The result of this paper can be used by both NH managers and material companies, resulting better quality of life of the elderly by providing safe environment.

• 한국가스학회지
• /
• 제18권4호
• /
• pp.35-43
• /
• 2014

무기질 바닥마감재로 기존 위험물 저장시설의 유기질계 바닥재의 문제점을 극복할 수 있다. 하지만 기존 시공된 바닥재를 제거하는데 있어서 제거기와 바닥재의 물리적 충돌에 의해 불꽃이 발생될 수 있다. 이러한 위험물 저장시설에서의 폭발에 의한 화재가 발생할 수 있는 위험요소를 억제하도록 기존 바닥재를 제거하지 않고 시공할 수 있다. 또한, 상도제는 대전방지제가 함유되어 있어 위험물 저장시설에 있어서 바닥마감재 시공 후 발생될 수 있는 정전기에 의한 2차적 피해를 억제 할 수 있어 효과적이다. 따라서 본 연구에서 개발된 무기질 바닥마감재는 점검자의 안전 관리적 측면과 경제적 측면에 효과가 있을 것으로 기대된다.

• 대한가정학회지
• /
• 제31권1호
• /
• pp.211-223
• /
• 1993

바닥마감재료가 다른 여름철의 찬바닥이 인체피부온도 및 온열적 쾌적감에 미치는 영향을 검토하기 위하여, 주위벽 및 천장의 온도를 기온과 거의 같게 한 항온실을 이용해서 바닥에 앉은 자세, 의자에 앉은 자세, 서 있는 자세별로 검토했다. 그 결과를 요약하면 다음과 같다. (1) 평균피부온도는 기온이 낮고 수온이 낮을수록 낮았다. Carpet 마감재료는 서 있는 자세, 바닥에 앉은 자세의 평균피부온도가 낮고 의자에 앉은 자세가 높았다. Cork 마감재료가 Carpet, Flooring 마감재료에 비해 평균피부온도가 낮았다. (2) 온냉감평가는 흑구온도가 낮게 되면$\ulcorner$중성이다$\lrcorner$혹은$\ulcorner$서늘하다$\lrcorner$쪽으로 평가하고, Cork, Carpet, Flooring 마감재료의 순으로 $\ulcorner$서늘하다$\lrcorner$쪽으로 평가 하였다. (3) 쾌적감평가는 바닥에 앉은 자세와 서 있는 자세가 의자에 앉은 자세보다 쾌적한 것으로 평가하였다. 마감재료는 Cork, Flooring, Carpet 순으로 쾌적하다고 평가 하였다. (4) 바닥마감재료에 대한 평가는 바닥에 앉은 자세의 경우, Carpet 마감재료는$\ulcorner$차가운$\lrcorner$$\ulcorner$습기찬$\lrcorner$의 평가점수가 높고, Cork 마감재료는$\ulcorner$평활한$\lrcorner$$\ulcorner$차가운$\lrcorner$$\ulcorner$감촉이 좋은$\lrcorner$$\ulcorner$딱딱한$\lrcorner$의 평가점수가 높고, Flooring 마감재료는$\ulcorner$평활한$\lrcorner$$\ulcorner$탄력성이 없는$\lrcorner$$\ulcorner$딱딱한$\lrcorner$의 평가점수가 높았다.$\ulcorner$따듯한$\lrcorner$-$\ulcorner$차가운$\lrcorner$의 평가는 바닥온도의 영향을 받아서, Cork, Flooring 마감재료가 Carpet 마감재료보다$\ulcorner$차가운$\lrcorner$의 높은 점수평가를 하였다. (5) Carpet 마감재료는 평균피부온도가 34$^{\circ}C$를 넘어도$\ulcorner$약간 시원하다$\lrcorner$는 평가이고, 서 있는 자세와 의자에 앉은 자세가 바닥에 앉는 자세보다 쾌적하다고 평가한다. Cork 마감재료는 3자세 모두 평균피부온도 33~34$^{\circ}C$의 사이에서 가장 쾌적하다. Flooring 마감재료는 온열적중성, 쾌적감의 중성의 평가가 많다. 이상의결과를 종합하면, 찬바닥이 인체에 미치는 영향은 바닥마감재료로는 Cork, Flooring이 보다 좋은 평가를 하였음으로, 여름철 바닥마감재료로서는 Cork, Flooring 마감재료가 바람직하다고 생각된다. 자세별로는 서 있는 자세는 바닥에 앉은 자세와 거의 같은 경향을 보이고, 의자에 앉은 자세는 바닥에 앉은 자세와 서 있는 자세 만큼 영향을 받지 않았다. 이후 실험결과를 중심으로 찬바닥의 경우, 보다 쾌적한 온열환경범위를 제안하려고 한다.

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 2008년도 춘계학술대회 논문집
• /
• pp.174-175
• /
• 2008

• Journal of the Korean Wood Science and Technology
• /
• 제33권4호통권132호
• /
• pp.23-29
• /
• 2005

대표적인 고부가가치 목질판상 재료인 마루판은 육안 분류 작업에 의한 오차로 마루판 시공 시에 무늬목간의 색상 차가 생기고 있다. 이는 조건등색(metamerism)에 의해 식별 후 혹은 마루판 시공 시에 오차가 큰 것으로 나타났다. 따라서 본 연구에서는 Light와 Dark 두 단계로 육안 식별한 피나무, 자작나무, 단풍나무 3수종의 무늬목을 사용한 마루판을 CIELAB를 이용하여 분류하고, CIERGＢ에서 각각의 문턱 값(threshold)을 조사하고, 인간의 색 인지에 기반을 둔 HSI (hue, saturation, intensity)색상모델을 응용하여 색상, 채도, 명도 값의 범위를 조사하였다. HSI색상모델의 색상과 채도, 명도를 이용하여 마루판의 색상분류에 사용할 경우 명도 값을 이용하는 것이 유리할 것으로 보인다. 그리고 색상의 범위가 3종류 모두 $45{\sim}55^{\circ}$ 사이 범위 값을 가지고 있는 것으로 보이며, RGB성분의 문턱값을 이용한 분류의 경우 특정 색상 성분 값만으로는 마루판 무늬목의 분류가 어려울 것으로 보인다.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2005년도 동계학술발표대회 논문집
• /
• pp.3-8
• /
• 2005

Building parts of Multi-Family Houses are consisted of several building material assembly. Therefore, after selecting building materials with test result of emission intensity and their feature, composed building materials are made equally with actual construction methods, and experimented emission intensity. 7 days after experiment, formaldehyde emission intensity appeared low in an order of Tile Wall, Wood Flooring, Wallpaper, Reum Flooring, Silk Wallpaper, and 20 days after experiment, TVOC emission intensity appeared low in an order of Tile Wall, Reum Flooring, Silk Wallpaper, Wood Flooring, Wallpaper. There was a clear difference in TVOC emission intensity according to kind of building materials. Composed building materials that weight per unit area is big and omission intensity is high, they effect continuously to indoor air because decrement is small.

• 음성과학
• /
• 제8권4호
• /
• pp.17-33
• /
• 2001

In this paper, we implement the large variable vocabulary speech recognition system, which is characterized by no additional pre-training process and no limitation of recognized word list. We have designed the system in order to achieve the high recognition rate using the decision tree based state tying algorithm and in order to reduce the processing time using the gaussian selection based variable flooring algorithm, the limitation algorithm of the number of nodes and ENNS algorithm. The gaussian selection based variable flooring algorithm shows that it can reduce the total processing time by more than half of the recognition time, but it brings about the reduction of recognition rate. In other words, there is a trade off between the recognition rate and the processing time. The limitation algorithm of the number of nodes shows the best performance when the number of gaussian mixtures is a three. Both of the off-line and on-line experiments show the same performance. In our experiments, there are some differences of the recognition rate and the average recognition time according to the distinction of genders, speakers, and the number of vocabulary.

• Environmental Engineering Research
• /
• 제23권4호
• /
• pp.354-363
• /
• 2018

We examined the levels of brominated flame-retardants (BFRs) including polybrominateddiphenyl ethers (PBDEs), tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), and phthalates in indoor dusts in residential houses in Korea, and their distribution patterns depending on building characteristics. Mean concentrations of phthalate esters ($1,825{\mu}g\;g^{-1}$) were significantly higher than that of BFRs (PBDE: $1,332ng\;g^{-1}$, HBCDs: $459ng\;g^{-1}$, and TBBPA: $213ng\;g^{-1}$), indicating more frequent use of phthalate-containing products such as PVC flooring in the Korean houses. PVC flooring house was associated with higher concentrations of DEHP (p = 0.001) and BBP (p = 0.012), indicating that exposure to phthalate was higher in the PVC flooring house. Building age was significantly related with levels of PBDEs especially BDE-47 (p = 0.062), BDE-203 (p = 0.007), DEHP (p = 0.004), and BBP (p = 0.070), respectively, indicating that older buildings can produce higher amounts of PBDEs and phthalates. Our study can provide important information on the sources of BFRs and phthalates in residential houses in Korea.