• 한국건설순환자원학회논문집
• /
• 제10권2호
• /
• pp.159-167
• /
• 2022

본 연구에서는 보통 포틀랜드시멘트를 사용한 콘크리트와 광물질 혼화재료 및 알칼리활성화제를 첨가한 4종류의 배합으로 시편을 제작한 후 X선 회절분석, 미세구조분석, 압축강도, 동결융해저항성 및 SEM Image 분석을 실시하여 각 배합별 강도발현, 상대동탄성계수, 중량변화 등을 측정하여 기초물성 평가를 진행하였다. 페로니켈슬래그 혼입 삼성분계 시멘트는 보통포틀랜드 시멘트 배합(OPC)과 비슷한 수화물을 생성하는 경향을 보였으며, MgO 성분으로 인한 팽창성 수화물은 확인되지 않았다. 페로니켈슬래그를 혼입 시 3성분계 시멘트(30SP20FN)의 경우 OPC와 비교 시 공극률이 커지는 경향을 보였지만, 알칼리활성화제를 첨가할 경우 공극 분포가 변화하는 경향을 보였다. 또한, 알칼리활성화제의 첨가는 30SP20FN의 장기강도발현을 앞당기는 효과를 보였으며, 18~26 % 가량 강도가 증가함을 확인하였다. 30SP20FN의 경우 dilution effect로 인한 낮은 수화도의 영향으로 동결융해저항성이 떨어졌지만, 알칼리활성화제를 첨가할 경우 높은 상대동탄성계수를 유지하였으며, 동결융해 저항성이 우수한 것을 알 수 있었는데, 이는 변화된 공극 분포 때문인 것으로 사료된다. 본 연구에서 실시한 상대동탄성계수 측정 실험에 사용된 콘크리트 시편 모두 300 사이클에서 상대동탄성계수가 60 % 이상으로 우수한 동결융해 저항성을 나타내었다. 동결융해 작용을 받은 콘크리트의 미세구조를 분석한 결과, OPC 및 30SP20FN 콘크리트의 경우 비정질의 수화물이 서로 결합되어 있지 않고, 미세 균열이 발생함을 확인한 반면, 알칼리 활성화제를 혼입한 배합의 경우 균질한 내부 구조를 유지하였다.

• 한국염색가공학회지
• /
• 제11권4호
• /
• pp.8-15
• /
• 1999

Electroconductive fiber was obtained by acryl fiber treated with $CuSO_4$. The Properties and structure of fiber and fabric such as mechanical property, electrical conductivity, fine structure, electrification were investigated. The experimental results are as follows 1) The electrical conductivity of the conducting fiber was greatly increased but fine structure and physical properties were similar to acryl fiber 2) Fabric made by mix spinning with conducting fiber was shown great electrification effect. 3) In the mix spinning with conducting fiber, it was necessary to use different. finishing such as milled finish because stiffness of fabric made by mix spinning with conducting fiber was increased and elastic recovery was decreased. 4) The antimicrobial activity of electroconductive fiber blended wool was effective by Cu component for shake flask test.

• 디자인학연구
• /
• 제16권4호
• /
• pp.443-452
• /
• 2003

본 연구는 면대면 학습의 장점과 e-Learning의 장점을 혼합한 블렌디드 러닝 방식이 오프라인 대학에서 디자인 교육이 갖는 문제점을 개선할 수 있는 방법으로 가능성이 있는지를 살펴보기 위한 것이다. 연구방법은 디자인 수업을 듣는 36명의 학생들에게 학습효과성에 기초한 다양한 분석요인과 전달방법의 특성을 고려하여 설계한 5단계의 블렌디드 러닝 모델을 적용하여 그에 대한 만족도를 설문을 통해 조사 분석하였다. 설문에 응한 학습자는 27명으로 대부분의 학습자들이 오프라인만의 교육보다 블렌디드 러닝방식을 더 선호한다는 긍정적인 반응을 나타냈다. 이는 블렌디드 러닝 방식이 디자인교육에서 효과적인 교육방법이 될 수 있음을 시사한다고 볼 수 있다. 향후 본 연구에 사용되어진 블렌디드 러닝 모델을 기초로 보다 활발한 천구와 현장 적용이 이루어진다면 디자인교육에서 보다 효과적인 학습모델을 찾을 수 있을 것으로 기대한다.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 1998년도 봄 학술발표회 논문집
• /
• pp.214-219
• /
• 1998

The characteristics of the Cotton/Polyester(C/P) blended slivers produced by drawing process have greatly influenced on the structure and properties of final yarns.$\^$1)/ Especially, since the unevenness of slivers is decreased greatly with passage of drawing, the optimum condition of drawing process is very important to improve the quality of yarns.(omitted)

• 폴리머
• /
• 제38권3호
• /
• pp.265-271
• /
• 2014

In order to investigate the characteristics of the gradient fluorinated polyacrylate and polyurethane latex blend films, the fluorinated polyacrylate emulsion and the polyurethane emulsion were synthesized, and then the both emulsions were blended at a series of ratios. The effects of content of the fluorinated polyacrylate on the gradient structure and surface property of the blended films were assessed by AFM, XPS, SEM-EDX and surface free energy measurements. It appeared that, while the content of the fluorinated polyacrylate latex was up to 30%, the fluorinated polyacrylate particles were selectively gathered on the film-air (F-A) and film-glass (F-G) interfaces at room temperature. When the content of the fluorinated polyacrylate was under 30%, the gradient structure of fluorinated component was not evident. The further increasing of fluorinated polyacrylate in the mixed system facilitated the formation and enlargement of gradient structure, but the adhesion of film decreased a little.

• 한국세라믹학회지
• /
• 제49권3호
• /
• pp.260-265
• /
• 2012

Impedance spectroscopy was used to monitor the hydration in the electrical/dielectric behaviors of chemical mechanical planarization (CMP)-blended cement mixtures. The electrical responses were analyzed using their equivalent circuit models, leading to the separation of the bulk and electrode based responses. The role of the CMP slurry was monitored as a function of the relative compositions of the CMP-blended cements, i.e. water, CMP slurry, and ordinary Portland cement. The presence of $Al_2O_3$ nanocrystals in the CMP slurries appeared to accelerate the hydration process, along with a more tortuous microstructure in the hydration, with enhanced hydration products. The frequency-dependent impedance spectroscopy was proven to be a highly efficient approach for evaluating the electrical/dielectric monitoring of the change in the pore structure evolution that occurs in CMP-blended cements.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 추계학술대회 논문집
• /
• pp.42-42
• /
• 2009

To make up for the disadvantages of PVA gate, we blend PVP(20% wt) with PVA(5% wt) as a gate material. The best ratio for the mixture was 5:5, PVP-PVA blended gate used MIM structure showed better performance in leakage current and capacitance. PVP-PVA blended gate was fabricated by spin-coating process and pentacene was used as an organic TFT channel layer by thermal evaporation. Overall OTFT performance has also increased as PVP-PVA blended gate has relatively lower leakage current and higher capacitance than pure PVA gate has.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
• /
• pp.1229-1234
• /
• 2001

The bottom slab of Inchon LNG in-ground #213 tank is designed as a massive structure witch has a large depth and section. The purpose of this study is to determine the optimum mix design having good workability and low hydration heat for bottom slab concrete and to control the actual concrete quality in site. For this purpose, we select the optimum mix design used ternary blended cement(furnace slag cement＋fly ash) and design factors. As test results of actual application, we have finish placing the bottom slab concrete of 23,180㎥ during 68hours with good success and obtain the good quality of fresh and hardened concrete including slump, air contents, no-segregation, compressive strength and low hydration heat in actual data. All test results are satisfied with our specifications for bottom slab concrete and we cut costs as the use of ternary blended cement and the reduction of placing hours.

• 한국건설순환자원학회논문집
• /
• 제8권1호
• /
• pp.39-48
• /
• 2020

본 연구에서는 철과 니켈의 합금강 제조공정에서 발생하는 산업부산물인 페로니켈슬래그를 혼입하여 기존 결합재와의 화학반응 및 성능을 확인하였다. 고로슬래그 미분말과 페로니켈슬래그를 활용하여 시멘트 대비 치환률 50%까지 삼성분계 치환하여 실험을 통해 기초 물성 및 특징을 평가하였다. 실험 결과에 따르면 페로니켈슬래그를 혼입할 시 포졸란 반응이 기여하여 밀실한 내부 공극 및 수화물이 형성되었고, 수화열과 건조 수축 감소 효과도 나타났다. 압축강도는 초기 재령에는 다소 저조한 강도발현을 나타냈으나, 28일 장기재령으로 갈수록 강도 증가가 나타났다. 추후 최적 배합을 도출하여 용도에 맞게 활용할 경우 시멘트 결합재로서의 활용 가능성이 기대된다.

• 복식문화연구
• /
• 제12권6호
• /
• pp.945-952
• /
• 2004

Shrink-resist effects and properties of the knitted fabrics from wool/acrylic(W/A) fiber blends were determined to find out an optimal blending ratio keeping the quality properties of wool products. The test fabrics were knitted by a weft knitting machine with all needle knitting structure ($0{\times}0$ rib) under the same knitting conditions with five different types of yarns: $W100\%,\;A100\%$, and W/A blended yarns(70/30, 50/50, 30/70). Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of W/A knits. The shrink resistance was significantly enhanced on repeated washing of W/A knits, especially, over $50\%$ acrylic blended knits. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that W/A blend knits can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling. W/A 50/50 blended knits did not bring serious changes to other physical properties comparing with original wool, which helps consumers care wool knitted clothes more conveniently.