• Journal of the Korea Concrete Institute
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• v.21 no.5
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• pp.557-563
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• 2009

This study is on the properties of inorganic porous calcium silicate material made from silica powder through the autoclaving curing, the results of this study should be utilized fundamental data for the development of noise reduction porous solid material using siliceous byproduct generated by various manufacture process. For the manufacture of autoclave curing specimen, various calcareous materials used and siliceous materials used silica powder. In this study, properties in density and compressive strength according to the change of W/B and C/S ratio, microscopy for the shape of pore, SEM and XRD for the examination of hydrate after autoclave curing are carried out respectively. The test results shown that the more slurry density decrease, the more W/B increase at the fresh state, this tendency shown similar to in hardened state. Among the specimens of C/S ratio, the compressive strength of C/S ratio of 0.85 gave the highest the compressive strength. In the results of XRD, tobermorite generated by autoclaving curing was created all of specimens regardless of C/S ratio. To ascertain pore structure, we compared with existing porous calcium silicate product(ALC, organic sound absorbing porous material). The results of microscope observation, pore structure of specimen of this study was similar to that of existing inorganic sound absorbing foam concrete. therefore, we could conformed a possibility of sound absorbing porous solid material on the basis of the results.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.3
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• pp.35-42
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• 2011

The exterior system of buildings, which is the typical curtain wall, has been made with glass and metal. Theses materials, however, have weaknesses such as inadequate insulating quality, short durability, combustibility and toxic substance. On the other hand, Autoclaved Aerated Concrete(AAC) or Autoclaved Lightweight Concrete(ALC) possess the great energy efficiency and the superb insulating quality as substitute of existing exterior system materials. In this research, strength characteristics and bubble dispersion of hydrothermal synthesis process of AAC based on CaO/$SiO_2$(C/S) ratio are analyzed. C/S ratio is determinated and bubble distribution and compressive strength are studied through the test of varied water-to-solid mineral ratio(W/S). In hydrothermal synthesis program, final C/S ratio is determined as 0.7 consider of the manufacturing process and hydrothermal synthesis is done at $180^{\circ}C$ for 7 hours. The analysis shows slurry has about 2,300cP viscosity and 0.56 specific gravity therefore it is expected AAC has the appropriate facility in the manufacturing process and Hydrates of AAC's Expansion.

• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.189-194
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• 1983

Raw and extruded barleys prepared by three different conditions were powdered and stored for four months at ambient $(25^{\circ}C)$ and accelerated temperatures $(40^{\circ}C)$ with $A_w$ of 0.31 and 0.71, respectively. The stability of the these samples with respect to lipid oxidation was studied. The lipid oxidation of all samples, as measured by the lipid diene conjugation of the extracted oil, increased with increased $A_w$ and temperature and with the storage time elapsed. The ratio of unsaturated to saturated fatty acids (U/S ratio) tended to decreased as the $A_w$ and temperature were increased. The raw sample had a greater increase in lipid conjugation diene but a decrease in U/S ratio than the extruded samples. The extruded sample containing the added sucrose had greater lipid stability than the other extruded samples. Lipid free-amino group content in all samples decreased with increased $A_w$ and temperature.

• Journal of Nutrition and Health
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• v.36 no.3
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• pp.245-254
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• 2003

The aim of this study was to investigate the effects of P/S ratio of fatty acid and antioxidant (vitamin E, selenium) supplements on the serum lipid levels and hepatic antioxidant enzyme activity in rats. Female 16-week-old Sprague-Dawley rats were fed 6 different experimental diets for 4 weeks. While the peroxidizability index (PI) levels of fatty acids in the experimental diets were fixed at 81.22, the levels of P/S ratio of fatty acids were formulated at 0.38, 1.00, 4.81 (LP, MP, HP). These diets were supplemented with vitamin E (1,000 mg/kg diet) and selenium (2.5 mg/kg diet) (LP-S, MP-S, HP-S). This study showed that the serum concentrations of total-cholesterol and HDL-C increased with the increasing of the P/S ratio in the diet (p <0.05). Antioxidant supplementation significantly lowered the concentrations of triglyceride (TG) and VLDL-C of serum (p<0.05). Levels of thiobarbituric acid reactive substance (TBARS) in the liver tended to decrease with the increasing of the P/S ratio in the diet (p<0.001), but antioxidant enzyme activity in the liver was not significantly different. In addition, antioxidant supplementation significantly lowered TBARS level in the liver (p<0.05), but had no effect on antioxidant enzyme activity except for glutathione reductase (p<0.05). In conclusion, it is necessary to consider the properties of dietary fatty acids and antioxidants supplementation for the prevention of cardiovascular diseases.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.545-548
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• 2008

In this study aluminium sulfate, Ca(OH)$_2$, K-R Slag and $Na_2SO_4$ were used as active admixtures and their concentration 1, 3, 5, 7 weight percent in cement. The physical properties of active admixtures cement mortar were investigated by flow test and compressive strength. It was found that the resulting active admixtures exhibited the higher compressive strength than OPC mortar up. From the test results, cement mortars added active admixture have a good fundamental property.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.198-207
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• 1999

Five core sediments acquired from the Lake Shihwa are analyzed for variations of sedimentary environment and heavy metal pollution after the Shihwa seawall construction. The depositional environment of the study area is divided into anoxic, oxic and mixed suboxic conditions based on the C/N ratio and C/S ratios of organic matters. Controlling factors for redox condition are the water depth and the difference in industrial effluents supply. Correlations among geochemical elements (Mn, U, Mo) show a distinctive difference and thus can be used as an indicator of redox condition. The content of Al, Ti are dependent on the sediment characteristics, and the contents of heavy metals (Cr, Ni, Cu, Zn, and Pb) indicate heavy metal pollution. The concentrations of heavy metals are higher near Shiswa-Banwol industrial complexies than the central part of Lake Shihwa. Especially, the accumulation of the heavy metal at the surface sediments near Shihwa-Banwol industrial complex are two to eight times higher than in the center of Lake Shihwa.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.2
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• pp.101-111
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• 2012

In the ALC(Autoclaved lightweight concrete) manufacturing process, if the pre-cured semi-cake is removed after proper time is passed, it will be hard to retain the moisture and be easily cracked. Therefore, in this research, we took the research by multiple regression analysis to find relationship between variables for the prediction the hardness that is the control standard of the removal time. We study the relationship between Independent variables such as the V/T(Vibration Time), V/T movement, expansion height, curing time, placing temperature, Rising and C/S ratio and the Dependent variables, the hardness by multiple regression analysis. In this study, first, we calculated regression equation by the regression analysis, then we tried phased regression analysis, best subset regression analysis and residual analysis. At last, we could verify curing time, placing temperature, Rising and C/S ratio influence to the hardness by the estimated regression equation.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.56-61
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• 1983

Direct production of biomass from starch using amylolytic yeast, Sporobolomyces holsaticus FRI Y-5 was studied with varying the ratios between carbon and other nutrient sources in the medium. It was investigated under condition of constant C/P and C/S ratio to influence the initial concentration of starch $(S_o)$ and C/N ratio on its growth which is described as the specific growth rate $({\mu})$, cell yield (Y), the maximum concentration of cell $(X_m)$, and productivity (P). They were very dependent on both $S_o$ and C/N ratio. The form of the relationship between and ${\mu}$ and $S_o$ was observed to be similar to saturation kinetics at C/N = 100 but presented substrate inhibition at other C/N ratios. As $S_o$ was changed from 22.5 to 90 g/l, Y was observed to vary with C/N ratios but seemed to decrease as a wholes. $X_m$ was linearly related to $S_o$ at more than C/N = 50 but at less than C/N = 10 substrate inhibition was presented. P increased suddenly to $S_o$ = 45 g/l and then changed decreasingly at less than C/N = 50, but at more than C/N = 100 it changed increasingly. The effect of C/P ratio and C/S ratio on the yeast growth was also investigated at constant $S_o$ and C/N ratio. ${\mu}$ was dependent on C/P and C/S ratios, but Y, independent on them. But $X_m$ was reliant upon C/P ratio but not upon C/S ratio.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.184-188
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• 2002

The fatty acid contents of egg yolk from various chicken eggs such as general egg, ginseng egg, gamgoal egg and docosahexaenoic acid (DHA) egg were analysed during storage at 4$^{\circ}C$ for 3 weeks. The major fatty acids of all egg yolk oils were oleic acid (18 : 1) and palmitic acid (16 : 0). The contents of both fatty acids reached maximum at the first or second week and decreased at the third week. DHA was detected from 4 kinds of eggs stored for 2 or 3 weeks. The n-6/n-3 ratio was obtained under recommended intake range in fresh gamgoal egg and in general and DHA eggs stored far 0~3 weeks. For 3 weeks, polyunsaturated fatty acid / monounsaturated fatty acid/ saturated fatty acid (P/M/S) ratio of DHA e99 did not chance, but that of ginseng e99 gradually increased. The P/M/S ratio was generally maintained under recommended intake range in general egg stored for 3 weeks, in ginseng egg stored for 2 weeks and in DHA egg during all the storage period.

• Proceedings of the KSCN Conference
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• 2003.11a
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• pp.1073-1074
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• 2003

본 연구는 고학력 중년 여성을 대상으로 취업 여부에 따른 영양섭취 상태의 차이를 분석하여 고학력 중년 여성의 영양 및 건강관리를 위한 대책 마련의 기초자료로 활용하고자 시행되었다. 연구 대상자의 선정은 유의추출 방법으로 전업 여성은 고학력자 비율이 높은 대전시의 일정 지역에 거주하는 기혼여성으로 하였고, 취업여성은 여러 직업의 특성으로 인한 교란(confounding)을 줄이기 위하여 고학력 여성의 비율이 높은 기혼의 교사로 한정하였다. 연령에 의한 교란을 방지하기 위하여 연령대별로 동일 비율로 무작위 추출하여 전업여성 250명, 취업여성 236명을 대상으로, 24시간 회상법을 이용하여 조사 전일 하루동안의 식이 섭취 내용을 개별 면담으로 조사하였다. 1일 영양소 섭취 조사 결과 취업여성은 전업여성에 비해 인, 비타민 B$_1$, B$_2$를, 전업여성은 취업여성에 비해 지방 및 동물성 지방, 나트륨, 비타민 C, 엽산을 많이 섭취하고 있었다. P/M/S비는 전업여성 1/1.19/1.05, 취업여성 l/l.05/0.87로 나타나 취업여성이 전업여성에 비해서, 그리고 한국인 영양권장량의 기준(1/1/1)에 비해서 포화지방의 비가 낮았다. 또한 지방 에너지 구성비도 전업여성(24.38%)이 취업여성(23.29%)에 비해 높았고, 총 열량에 대한 동물성 지방의 섭취비율이 전업여성 12.44%, 취업여성 11.46%으로 나타나 전업여성이 취업여성에 비해 동물성 지방, 포화지방비, 지방에너지 구성비가 모두 높았다. 영양권장량에 대한 영양소 섭취 백분율에서 전업여성과 취업여성 모두 칼슘과 아연을 권장량에 비해 낮게 섭취하고 있었고, 질적 영양지수(INQ)도 두 군 모두에서 칼슘이 가장 낮게 나타났다. 인의 영양밀도(Nutrient Density)가 취업주부에서 높았던 점 외에는 영양밀도와 영양소 적정섭취비(NAR) 모두에서 비타민 B$_1$, B$_2$가 전업여성에 비해 취업여성이, 비타민 C가 취업여성에 비해 전업여성이 더 높았다. 한편 두 군 모두 INQ가 가장 높은 영양소는 인이었고, INQ가 가장 낮은 영양소는 칼슘으로 나타났으며, INQ가 1 미만인 영양소는 칼슘과 함께 철분으로 나타났다. 이는 1998년도 국민건강영양조사 결과에서 45세 이상 여성의 경우 관절염, 요통.좌골통, 디스크 등 근골격계질환 유병률이 남자보다 3배정도 높게 나타난 결과에 비추어볼 때 이들 관련 영양소에 대한 섭취 방안 지도의 필요성을 제시하고 있다. 결론적으로 고학력 중년 여성중 전업여성에 대해서는 지방 특히 동물성 지방 식품 섭취에 대한 적절한 영양교육과 식사관리 지도가 요구된다 하겠다. 또한 고학력 중년 여성은 취업 여부에 관계없이 칼슘과 철분이 많이 함유된 식품으로 식사량을 증가시켜 주는 영양 지도 및 영양 보강 대책이 요구되며, 칼슘과 인의 적정섭취비가 되도록 인의 섭취를 낮추는 식생활 지도가 필요하다.