• 한국산학기술학회논문지
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• 제20권12호
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• pp.715-722
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• 2019

콘크리트 구조물은 외부로부터 콘크리트 내부로 침투 및 확산하는 유해 이온(CO₃^2-, Cl^-, SO₄^2- 등)에 의하여 철근의 부식 및 콘크리트 열화가 발생하여 내구성이 저하된다. 따라서 콘크리트의 열화를 방지 또는 지연시키기 위하여 콘크리트 표면 보호용 마감 모르타르의 사용은 매우 중요하다고 할 수 있다. 본 연구에서는 실리카 졸과 칼슘 이온으로 개질한 천연 라텍스 성분을 열화 콘크리트의 보수용 모르타르 또는 콘크리트 표면 보호용 마감 모르타르에 사용할 수 있는 시멘트 모르타르에 사용함으로써 콘크리트의 열화 방지 또는 열화 지연의 가능성에 대해 검토하였다. 연구 결과, 개질 라텍스 성분 중에 함유된 칼슘 이온과 실리카 졸의 성분에 의해 미세한 칼슘 실리케이트 수화물이 시멘트 재료의 공극에 생성되어 시멘트 모르타르의 공극 분포를 감소시켜 유해 이온(CO₃^2-, Cl^-, SO₄^2- 등)의 침투 및 확산을 저감 시키고, 라텍스 성분이 시멘트 경화체의 공극 내부에 존재함으로 내알칼리성 및 중성화 저항성이 향상됨을 확인할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제37권1호
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• pp.12-18
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• 2009

본 연구는 실내마감자재가 실내공기질에 미치는 영향을 조사하기 위하여 목재주택 내 친환경 마감자재로 처리한 시험실 내부의 카르보닐화합물의 방산특성을 조사하였다. 실험 결과 포름알데히드, 아세톤 및 헥사알데히드가 카르보닐화합물의 대부분을 차지하였으며, 이 중 포름알데히드가 25.6~30.5%로 가장 높은 비중을 차지하였다. 시험실 R2-2를 제외한 모든 시험실에서 포름알데히드 방산량이 신축 공동주택의 실내공기질 권고기준치 이하를 나타내었고, 아세트알데히드의 경우 시험실 R1-3을 제외한 나머지 시험실에서 일본 후생노동성에서 제시한 기준($48{\mu}g/m^3$)을 초과하는 것으로 나타났다. 황토벽지를 사용한 R1-1에서 상대적으로 높은 방산량을 나타내었고, 대나무숯 패널을 설치한 R2-2에서 모든 카르보닐화합물에 대해 높은 방산량을 나타내었다. 편백으로 치장한 거실인 시험실 R1-3은 나머지 시험실에 비해 아세톤을 제외하고 전반적으로 낮은 포름알데히드와 카르보닐화합물 방산량을 나타내었다.

• 한국염색가공학회지
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• 제21권6호
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• pp.1-11
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• 2009

Super-hydrophobic surface, with a water contact angle greater than $150^{\circ}$, has a self cleaning effect termed 'lotus effect'. We introduced super-hydrophobicity onto aramid/rayon mixture fabric with dual-scale structure by assembling silica nano-sol. Mixture fabric was treated with silica nano-sol, fluoric polymer using various parameters such as particle size, concentration. Silica nano-sol size were measured using particle size analyzer. Morphological changes by particle size were observed using field emission scanning electron microscopy(FE-SEM), contact angle measurement equipment. The contact angle of water was about $134.0^{\circ}$, $137.0^{\circ}$, $143.0^{\circ}$, $139.5^{\circ}$ and $139.0^{\circ}$ for mixture fabric coated with 100.2nm, 313.7nm, 558.2nm, 628.5nm and 965.4nm silica nano-sol, compared with about $120.0^{\circ}$ for mixture fabric coated with fluoric polymer. When we mixed particle sizes of 100.2nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $146.2^{\circ}$. And we mixed particle sizes of 313.7nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $141.8^{\circ}$. Also we mixed particle sizes of 558.2nm and 965.4nm by 7:3 volume ratio, the best super-hydrophobicity was obtained. In this paper, we fabricated the water-repellent surfaces with various surface structures by using four types of silica nano-sol, and we found that the dual-scale structure was very important for the super-hydrophobicity.

• 대한가정학회지
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• 제11권3호
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• pp.276-284
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• 1973

An experiment, aimed at finding out the adhesive condition when adhesive non-woven fabrics for padding cloths are used for padding cloths of blouse, has been conducted. Materials used were three different kinds-scoured, sanforized, and permanent pressed- of combined fabrics of polyester and cotton. As for padding cloth material, mixed spinning nonwoven fabrics of polyster and viscose rayon have been used. Adhesive conditions were made each at $120^{\circ}C$, $140^{\circ}C$, $160^{\circ}C$ and $180^{\circ}C$, respectively, and adhesive time has been limited to 5, 10, 20, 30, 40 seconds each. External appearance as well as quality have been watched through washing experiment. In case of 12$0^{\circ}C$, all experimental materials were separated at the seventh washing and as for $140^{\circ}C$, all but the material which has been attached on scoured cloth for 40 seconds were separated. In case of 20 seconds only permanent pressed cloth and sanforized cloth were separated. At 30 and 40 seconds, the adhesive conditions have been maintained up to the seventh washing. In case of 5 seconds $180^{\circ}C$it was not turned yellow, but all were separated. In case of 10, 20, 30 and 40 seconds, at above temperature all were turned yellow in the adhesive process. Therefore, the adhesive power could be said strong enough, though it was not very practical. In this experiment, the lower the temperature of iron is, the longer time it has to be touched. At higher temperature however, relatively short time makesn it possible for adhesion and depending upon the finishing methode of cloth, there is slight difference in adhesive power. As a result, the best adhesive condition for all experimental materials is $160^{\circ}C$of iron temperature, and the time of adhesion is between 30 and 40 seconds.

• 한국염색가공학회지
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• 제18권4호
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• pp.43-48
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• 2006

나일론섬유에 대한 프탈로시아닌 반응성 염료의 염착거동을 관찰하기 위하여 온도 및 pH를 변화하여 이에 관한 흡착율(%) 및 고착율(%)의 변화를 관찰하였다. 또한, 염착실험과정과 관련하여 새로운 적용 방법으로 실험적 모델링 방법을 도입하여 흡착율(%) 및 고착율(%)을 예측하고, 이의 결과를 여러 온도 및 pH 조건에서의 실제실험과의 상호작용 및 효과를 확인하였다. 수학적 모델링의 타당성은 Excel 회귀분석단위를 이용하여 확인하였다. 예측 모델에 있어서 얻어진 높은 계수간의 상관관계(흡착율(%) $R^2=0.9895$, 고착율(%) $R^2=0.9932$)는 실제로 진행되지 않은 실험조건에 대한 결과에 있어서도 우수한 예측 정보를 제공할 수 있다. 그리고 실험적 결과로부터 확립된 예측가능한 다항식이 ANOVA 통계적 개념에 의해 자세하게 분석되었다.

• 한국염색가공학회지
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• 제20권2호
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• pp.19-28
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• 2008

The objective of this study was to apply the statistical technique known as design of experiments to optimize the % exhaustion variables for phthalocyanine dyeing of nylon fiber. In this study, a three-factor Central Composite Rotatable Design (CCRD) was used to establish the optimum conditions for the phthalocyanine reactive dyeing of nylon fiber. Temperature, pH and liquor ratio were considered as the variable of interest. Acidic solution with higher temperature and lower liquor ratio were found to be suitable conditions for higher % exhaustion. These three variables were used as independent variables, whose effects on % exhaustion were evaluated. Significant polynomial regression models describing the changes on % exhaustion and % fixation with respect to independent variables were established with coefficient of determination, R2, greater than 0.90. Close agreement between experimental and predicted yields was obtained. Optimum conditions were obtained using surface plots and Monte Carlo simulation techniques where maximum dyeing efficiency is achieved. The significant level of both the main effects and interaction was observed by analysis of variance (ANOVA) approach. Based on the statistical analysis, the results have provided much valuable information on the relationship between response variables and independent variables. This study demonstrates that the CCRD could be efficiently applied for the empirical modeling of % exhaustion and % fixation in dyeing. It also shows that it is an economical way of obtaining the maximum amount of information in a short period of time with least number of experiments.

• 한국가구학회지
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• 제21권5호
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• pp.380-391
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• 2010

Modular furniture's colors, materials, finishing materials and quantities are determined by users' tastes and it's diverse functions, shapes and sizes are determined by the spaces of users. That is, modules satisfy the diversity of consumers, meet differentiated individuals' tastes and enable communications with consumers rather than delivering one-way messages of designers. The contemporary spaces of the 21st century have been gradually shifting from uniform spaces attaching weight on individuals' individuality and tastes and along with it, the consumption of expensive custom-made furniture and foreign branded furniture is increasing to satisfy those small numbers of consumers who want to express diversified individuality. The modular furniture as a concept which is the most suitable to Mass Customization can be produced in large quantities while considering the diverse needs and tastes of individuals and it does not have absolute shapes or sizes. The concept of modular furniture shows similarities to the creation of fractals that forms shapes by self similarities, repeats and similar transformations which is in the same context as the characteristics of a modular design that presents diversity with scales, materials and jointing points. Fractals will be combined with the digital media of today to present great plasticity and influence designers more heavily. Pursuit of new modeling is a requisite for the creation of future spaces and it will require continuous creativity and the transformable modular furniture will contribute to the satisfaction of diverse consumers' needs. This study is to propose the modular furniture that considers the diversity of the public in the 21st century and their individuality and that will enable interactions between designers and consumers.

• 한국염색가공학회지
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• 제27권2호
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• pp.132-141
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• 2015

Fall-arrest systems(maximum arrest force and allowable free-fall) have been widely applied to provide a safe stop during fall incidents for various industrial activities. Fabric structure affects on the mechanical properties of shock energy absorber. The object of this study is to perform the basic research for the evaluation of the capacity of fall arrest energy absorber in relation to the different interlace yarn density. In this work, pack style energy absorber was prepared by weaving 10 types(Interlace yarn density used high tenacity PET 1000D : 60, 59, 58, 57, 56, 55, 54, 53, 52, 51). The paper presents the results of theoretical investigations of the performance of adjustable absorber during fall arrest. Dynamic load tests based on the EU fall protection equipment standard(CE : EN355:2002) were conducted. Results showed that the maximum arrest force by dynamic load test of energy absorber was satisfied with global standard(below 6,000N). Also, Maximum allowable free-fall of energy absorber showed below 1.75m.

• 한국가구학회지
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• 제27권4호
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• pp.335-342
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• 2016

In previous study, volatile organic compounds (VOCs) emission characteristics were highly affected by coating materials for wood finishing. Natural based coating materials showed that about 15~46% lower TVOC emission than typical products. In this study, long-term changes of VOCs emission characteristics from pine panel with three types of coating treatments were determined. Non-treated pine panel emitted $604.7{\mu}g/m^2{\cdot}h$ of TVOC that contained 66% of NVOC ($399.7{\mu}g/m^2{\cdot}h$) at 0 month. After 10 month, TVOC reduced 88% and 93% reduction on NVOC was observed. Natural oil and waterborne stain treated pine panel showed 61% and 77% lower TVOC, respectively, than non-treated pine panel. However, TVOC from finished pine panels showed higher TVOC emission than non-treated pine panel. All samples satisfied the VOC emission regulation (below $4,000{\mu}g/m^2{\cdot}h$) by Korean Ministry of Environment. Toluene emission regulation (below $80{\mu}g/m^2{\cdot}h$) was passed on all sample without varnish treated pine panel at 0 month. According to HB qualification standard for construction materials by Korea Air Cleaning Association (KACA), wood is not qualified to get the best tag due to high TVOC emission. At the 10 months, only non-treated pine panel could get the best tag of HB from KACA.

• 한국토양비료학회지
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• 제49권6호
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• pp.760-767
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• 2016

Food waste (FW) has been recognized as a critical problem in Korea and many research was conducted to efficiently utilize or treat FW. Main purpose of this research was to evaluate a feasibility for producing fermented organic fertilizer with vegetable waste (VW). Three different organic materials (saw dust, coco peat, and waste mushroom media) were mixed with VW at the rate of 30, 40, 50% respectively. Total days of composting experiment were 35 days and each sub samples were collected at every 5 days from starting of composting. Result showed that inner temperature of composting was increased to $60{\pm}4^{\circ}C$ within 5~10 days depending on varied organic materials and mixing ratio. Among different treatment, the highest increase of inner temperature was observed when 30% of saw dust was mixed with VW. After finishing composting experiment, maturity of each compost was evaluated with solvita and germination test. Maturity index (MI) of each treatment was ranged between 5~7 indicating that manufactured fertilizer was curing or finished stage. Calculated germination index (GI) was at the range of 57.83~101.16 depending on organic materials and mixing ratio. Both MI and GI showed that manufactured fertilizer was met for fertilizer criteria while control (VW only) was not adequate for composting. Overall, VW can be utilized for making organic fertilizer mixing with saw dust, coco peat and more research should be conducted to make high quality of organic fertilizer with vegetable waste.