• Cement
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• s.66
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• pp.12-15
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• 1977

석회석과 고로수재 slag을 1.6 : 1로 혼합 분쇄한 원료를 1,450$^{\circ}C$에서 소결하여 고$C_3A$ clinker를 얻었다. 이 clinker 중에는 $C_3S$ 40$\%$, $C_2S$ 31$\%$, $C_3A$ 22$\%$, $C_4AF$ 2$\%$를 함유하고 있으며 보통 크링카 보다 $C_3A$ 함량이 2$\~$3배 정도 높고, clinker 색은 연두색을 띄는 것이 특색이다. 이와 같이 $C_3A$ 함량이 높은 시멘트의 특성 및 제조 가능성을 검토한 결과는 다음과 같다. 1) 석회석과 slag를 1.6 : 1(61.5$\%$ : 38.5$\%$)로 사용할 경우 보통 시멘트 제조시 석회석 사용량 보다 약 28$\%$ 정도 절감되나 고품위의 석회석이 요구된다. 2) 동일 free CaO 0.4$\%$를 기준으로 소성할 경우 고$C_3A$ clinker가 보통 clinker 보다 소성 시간이 20분 단축된다. 3) carbonate 분해열을 비교하면 고$C_3A$ 시멘트 원료가 보통 시멘트 원료보다 116Kcal/$\cal{kg}$-cl 절감된다. 4) $C_3A$ 함량이 높아 가소성이 저하되고 표준연도의 시멘트 paste를 얻기 위하여서는 보통 시멘트 보다 많은 물량이 요구되며 응결시간도 빠르다. 5) Blaine 3,000$cm^3$/g으로 분쇄한 고$C_3A$ 시멘트의 3 일강도는 보통 시멘트 보다 40$\~$50$\cal{kg}$/$cm^3$ 더 높으나 28 일 강도는 다소 저하되는 경향이며 Blaine 5,000$cm^2$/g으로 분쇄한 고$C_3A$ 시멘트는 조강 시멘트와 같은 강도 수준이다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.582-586
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• 1999

The processing conditions for producing and edible alginate film from sea tangle were investigated by measuring water vapor permeability (WVP), tensile properties and colors of film. The alginates were extracted with $3\%$ sodium carbonate ($Na_2CO_3$) solution for 5 hrs, and the alginate films were prepared with extracted sodium alginates, D-gluconic acid lactone, $CaCO_3$ and various plasticizers, As the concentration of alginate in making the film was increased, the WVP and elongation of the film were decreased and the tensile strength was increased. The higher amount of plasticizer showed the higher WVP and elongation, and the order of various plasticizers in increasing the WVP and elongation of the film was glycerol, polyethylene glycol, and sorbitol. The addition of sorbitol in the film showed the highest value (89.57) in lightness of Hunter color system and the film added polyethylene glycol had the highest values (-1,12 and 11.4) in redness and yellowness.

• Science of Emotion and Sensibility
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• v.6 no.2
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• pp.37-47
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• 2003

The objectives of this study were to find the relationship between the olfactory sense such as perfume and sense of sight and how it affects the sensibility based on the fact that ,senses are compound feeling from detective parts of human body. First, to build the emotional rate stale we selected the 19 pairs of adjective from the previous studies that overlaps smell, color, and clothes and added one pairs of related clause. Then each pair was divided into 7 level of emotional stage. In the experiment by the selected 15 man and woman from the visual design major student of Hong-ick Univ each student was given floral, jasmin, lavender, papaya and asked them to pick one color from I.R.I Hue & Tone chart for each smell. Then, analyzed the emotional rating of selected color for given smell. The emotional structure of smell and color consists five parts; 'Esthetics', 'Romance', 'Character', 'Intensity', 'Nature', There were significant differences in frequencies of selected colors for each given smell and gender difference also affected the color selected. Average value of emotional rating scale of smell and color was ,similar to the results from previous studies on relationship between smell and emotion.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.11
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• pp.949-956
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• 2016

There are a number of effects by solar radiation in many aerospace industrial fields, such as degradation of mechanical properties, sealing effect of sealants or decolorization. Because it takes long time to investigate these effects by using the light of natural state, new methods are developed for accelerating this phenomenon. In this paper, we developed an apparatus to simulate accelerated solar radiation phenomenon selecting irradiation intensity $1,120W/m^2$ as the designed environment. Epoxy polymer as the composite material was chosen and processed by ASTM-D638, a reference for tensile test of polymer and plastic. Total color shift was selected as the test category to evaluate acceleration of the test. We obtained acceleration factors and numerical model from test data and concluded it can shorten test periods by accelerated irradiation intensity of $1,120W/m^2$.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.815-823
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• 2014

Green tea has been known to show beneficial effects on alleviating stress. The present study was conducted to determine the effects of dietary green tea on quality of eggs, during storage, laid by laying hens treated with corticosterone in order to mimic the current practice of the egg market. Hens were fed for 2 weeks one of three diets containing green tea at 0.0, 0.4 or 1.0%. Each dietary group was divided into two subgroups receiving corticosterone at 0 or 30 mg/kg for 1 week. Eggs, laid at 5-7 days following the initiation of corticosterone treatment, were stored at $10^{\circ}C$ for 1 or 5 weeks and then analyzed for egg quality. After 1 week of storage, egg weight was significantly increased by green tea (p<0.025) but decreased by corticosterone (p<0.0001), but no interaction was observed between both. Corticosterone decreased shell color (p<0.0001) but green tea significantly decreased shell strength (p<0.006). Yolk color, albumen height and Haugh unit were not affected by both treatments. After 5 weeks of storage, corticosterone resulted in reduced egg weight (p<0.01) and eggshell color (p<0.001) and increased shell strength, which were not attenuated by green tea. Taken together, the results of the current study show that dietary corticosterone reduces egg quality during storage, which are attenuated in part by dietary green tea.

• Korean Journal of Dental Materials
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• v.44 no.2
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• pp.129-139
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• 2017

This study investigated the colors and mechanical properties of layered dental composites. Four nanocomposite resins (Aelite LS, Grandio, Tetric EvoCeram, Filtek Z350XT) and a silorane-based composite resin (P90) were used for overlying and underlying materials, respectively, with different thickness combinations. Colors, translucency parameter (TP), flexural and compressive properties were evaluated. All tested specimens had different color coordinates, although all were of A3 shade. Color coordinates and TP values of layered specimens better matched those of the corresponding overlying product as the thickness of the overlying product was increased. High TP values were related with high $b^*$ value differences between specimens (p<0.05). Both flexural strength and modulus, compressive strength and modulus of layered specimens with different thickness combinations were mostly lower than those of the corresponding overlying products, respectively, in their non-layered state.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.3
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• pp.18-29
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• 1993

In single mode fiber optic transmission systems(FOT's) operated at high modulation rates over long fiber spans, chromatic dispersion can produce distortion in the demodulated waveforms, resulting in intersymbol interference(ISI) in the received signal and a reduction of transmission system performance. In this paper, chromatic dispersion limitations for intensity modulation and direct detection(IM-DD) systems are studied by considering the effect of phase modulation to amplitude modulation (PM-AM) conversion noise. Laser phase noise conversion to amplitude noise due to fiber chromatic dispersion is analyzed by deriving the noise power spectral density. We first derive the noise power spectral density of the laser phase noise to intensity noise conver- sion. Next, also evaluate the system power penalty and the transmitter laser linewidth required to avoid PM-AM conversion noise penalties in long-haul nonregenerative transmission system using an external modulator and optical amplifiers. For such system with optical amplifiers, transmission sys- tem length is limited due to fiber chromatic dispersion, even if an ideal external modulator is used.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.101-102
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• 2004

The observed means and standard divisions of the egg texture per generation in korean native chickens were as follow. The egg shell strength, the egg shell thickness and the egg shell colour were 3.8$\pm$0.2~4.2$\pm$0.1 kg/$\textrm{cm}^2$, 356.4$\pm$4.9~368.8$\pm$6.5${\mu}{\textrm}{m}$ and 47.0$\pm$1.7~50.0$\pm$3.3％. The regression coefficients were -0.03~0.03 kg/$\textrm{cm}^2$, -0.84~4.40${\mu}{\textrm}{m}$ and -0.88~-0.36％ respectively.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.22-22
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• 2011

Ramie는 통풍이 잘 되고 시원하며 가볍고 촉감이 깔깔하여 우리 나라에서 예로부터 여름 옷감으로 사용되어 왔다. 그러나 가격이 비싸고 열에 약한 단점이 있어 가격이 저렴하고 형태 안정성이 우수한 PET와 혼방된 제품으로써 많이 생산되고 있다. 혼방물의 염색 시 각 섬유는 본연의 특성에 맞는 염료를 사용하여 염색하게 되는데, 제품으로 사용하기 위해서는 염색 후 두 섬유의 색 강도를 같게 해줘야 한다. 그러므로 Ramie 섬유의 염색에 사용되는 반응성 염료와 PET 섬유의 염색 시 사용되는 분산염료가 같은 색강도를 가질 수있도록 각 염료의 농도를 찾아내는 것이 중요하다. 혼방물의 염색방법에는 각 섬유의 적합한 염색 조건에 맞는 2개의 염욕에서 순차적으로 염색하는 2욕 염색법과 하나의 염욕에서 각 섬유에 적합한 염색을 진행시키는 1욕 염색법이 있다. 2욕 염색법은 각 염료의 최적조건에서 염색하므로 염색성 및 견뢰도를 극대할 수 있다는 장점을 가지고 있는 반면, 소요시간이 길고 폐수의 양이 많다는 점을 고려할 때 향후 1욕 염색법이 경제적, 환경적 측면에서 효율적이라 할 수 있다. 본 연구에서는 Ramie/PET 혼방섬유의 1욕 염색법과 2욕 염색법을 이용한 염색성을 고찰을 통해 1욕 염색법의 적용 가능성을 고찰하였다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.239-241
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• 2008

강도, 경도가 약한 송이석을 골재로 활용한 콘크리트는 포트란트 시멘트로서는 강도가 약하여 제조가 불가능하였다. 강도를 증강시키기 위하여 CSA를 함유한 특수시멘트를 포트란트 시멘트에 40% 첨가함으로서 우수한 성능을 갖는 고기능성 투수콘크리트이 제조가 가능하였다. 자연색을 갖는 콘크리트를 제조하기 위하여 송이석의 분말을 첨가함으로서 개발이 가능하였으며, 송이석이 갖고 있는 물의 정화작용도 갖고 있음이 확인 되었다. 따라서 송이석을 갖는 콘크리트를 시공하면 빗물을 깨끗하게 정화시켜 지하로 보낼 수가 있다. 하천으로 흘러 보내는 빗물을 지하로 보냄으로서 지하수의 보존은 물론이고 깨끗한 지하수를 얻을 수가 있는 고기능성 투수콘크리트의 시공은 저렴한 비용으로 많은 효과를 얻을 수가 있다.