• 정보처리학회논문지D
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• 제10D권7호
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• pp.1085-1092
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• 2003

대용량, 고속의 멀티미디어 서비스가 일반화됨에 따라 컨텐츠를 저장하는 서버의 저장 장치 또한 대용량화되고 있다. 그러나 서버를 구성하는 다른 하드웨어 구성 요소에 비해 상대적으로 느린 저장 장치의 입출력 속도와 물리적 또는 논리적인 오류는 시스템 전반의 성능을 저하시키는 원인이 되고 있다. 또한 컨텐츠의 지속적인 증가로 인한 유연한 확장성이 필요하게 되었다. 본 논문에서는 이러한 문제점을 해결하기 위해 소프트웨어 RAID 사용하여 저장 장치의 성능을 향상시키고 신뢰성을 높였으며, LVM을 사용하여 저장 장치에 확장성을 부여하였다. 리눅스 커널 2.4.x에서 제공하는 이러한 기능들을 사용하여 신뢰성과 확장성이 있는 저장 장치를 구현하고 성능을 평가하였다.

• Food Science and Biotechnology
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• 제15권5호
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• pp.683-687
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• 2006

The respiration rate of Chinese quince was measured at 0, 5, 10, and $20^{\circ}C$ to determine its tolerable range of storage temperatures. Based on the measured respiration rates, plastic films covering a wide range of gas permeabilities were used for packaging and storing individual Chinese quince at 0 and $10^{\circ}C$. Chinese quince can be categorized as low respiration fruit. Higher respiratory quotients were observed at higher temperature suggesting that the tolerable temperature range for storage is $0-10^{\circ}C$. Packages containing Chinese quince wrapped in highly gas-permeable polyolefin film PD 941 attained, with progressive decreases in volume, 9.5-10.2% $O_2$ and 1.3-1.8% $CO_2$ at $0^{\circ}C$, 8.1% $O_2$ and 2.4% $CO_2$ at $10^{\circ}C$. At these levels, PD 941 could preserve the fruit at acceptable quality levels for 152 and 50 days at 0 and $10^{\circ}C$, respectively. Less gas-permeable packages built up high $CO_2$ concentrations (above 15.8%) and low $O_2$ concentrations (less than 1.8%) causing free volume expansion and eventual dark discoloration of the fruit. The storage life realized by packaging with polyolefin film PD 941 could facilitate the availability of Chinese quinces in winter and spring for medicinal or ornamental purposes in the fresh state.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.986-990
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• 2009

Using artificial rainfall simulator, the soil loss, which is deemed as most cause of muddy water problem among Non-point source(NPS) pollutant, was studied by the analysis of direct runoff flow, groundwater runoff, and groundwater storage properties concerned with rainfall intensity, slope of area, and land cover. The direct runoff showed increasing tendency in both straw covered and bared boxes which are 5%, 10%, and 20% sloped respectively. Also the direct runoff volume from straw covered surface boxes were much lower than bared surface boxes. It's deemed as that the infiltration capacity of straw covered surface boxes were increased, because the surface sealing by fine material of soil surface didn't occurred due to the straw covering. Under the same rainfall intensity and slope condition, 2.4 ${\sim}$ 8.2 times of sediment yield were occurred from bared surface boxes more than straw covered surface boxes. The volume of infiltrated were increased due to straw cover, the direct runoff flow were decreased with decreasing of tractive force in surface. To understand of relationship the rate of direct runoff flow, groundwater runoff, and groundwater storage by the rainfall intensity, slope, and land cover, the statistical test was performed. It shows good relationship between most of factors, expect between the rate of groundwater storage and rainfall intensity.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.45.2-45.2
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• 2011

Metal organic frameworks (MOF) have generated considerable interests as a potential candidate for hydrogen storage owing to their extremely high surface-to-volume ratio and low density. In this study, Pt nanoparticles of about 3 nm in size were introduced outside MOF-5 [$Zn_4O$(1,4-benzenedicarbocylate)3], which was then encapsulated with hydrophobic microporous carbon black (denoted CB@Pt/MOF-5) in order to enhance hydrogen uptake capacity without decreasing the specific surface area and hydrostability. To study the chemical composition, morphology, crystal information, and properties of the synthesized material, a variety of techniques is employed, including WXRD, XPS, ICP-AES, FE-SEM, HR-TEM, and N2 adsorption-desorption, confirming the formation of novel hybrid composite designated CB@Pt/MOF-5 with highly crystalline structure, large specific surface area and pore volume. In addition, $H_2$ storage capacity for resulting material was measured using magnetic suspension microbalance at 77 and 298 K under high-pressure condition, and the hydrostability was also tested by exposing the sample to 33% relative humidity at $23^{\circ}C$ and measuring XRD as a function of time.

• 한국작물학회지
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• 제56권2호
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• pp.107-112
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• 2011

Oat flour was purchased and investigated for quality characteristics of oat bread. Antioxidant and flour pasting properties of oat flour, and water content, weight, volume, Hunter color value, texture of bread were measured. DPPH radical scavenging capacity (%) of oat extract was 68.49%. Pasting temperature of oat flour ranged between $66.60^{\circ}C$ and $70.93^{\circ}C$. Flour pasting properties of sample added with 10 and 30% oat flour was shown similar results compared with wheat flour. Final viscosity of sample was increased by adding concentration of oat flour (up to 311.65 RVA). Water content (%) of bread was shown increasing trend by adding oat flour. Weight of bread loaf with 100% oat flour was shown higher score than other samples. Volume of loaf by adding oat flour of 10, 30, and 50 % ratio was 550, 450, and 388 mL, respectively. The Hunter color $L^*$ values of bread by adding oat flour was dark compared with wheat bread. Color value of bread added 10% oat flour was similar results with $L^*$ values of bread with wheat flour. The bread added with 20 and 30% oat flours had the higher hardness, gumminess, and chewiness compared with other samples. Cohesiveness of the bread with wheat flour showed higher than that of bread added with oat flour and increased by storage period. The growth of total viable cell was inhibited depending on the concentration of oat flour during storage.

• 한국물환경학회지
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• 제22권1호
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• pp.97-103
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• 2006

Excess sludge treatment and disposal currently represent a rising challenge for domestic or wastewater treatment plants due to economic, environmental and regulation factors. Conventional gravity sedimentation process has been widely used in sludge thickening. The operation method of the process is very simple, but the process requires long detention time for sludge thickening, uses polymers, and shows low sludge thickening efficiency. To solve the problems, we studied on DAF (Dissolved Air Flotation) system. We use bulking sludge of a paper manufacturing plant. The effects of parameters such as SVI (Sludge Volume Index), storage time, initial concentration and wet density of excess sludge were examined. The results showed that the more SVI was low, the more sludge was thickened. As storage time goes by, SVI was increased and thickening performance was deteriorated. In order to improve flotation performance at high concentration, high recycling ratio and pressure did not increase the concentration due to thickening limitation. The addition of 0.8 g/L of loess was increased flotation efficiency of 1.41 times.

• 동아시아식생활학회지
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• 제20권6호
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• pp.863-872
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• 2010

The overall effects of three different beers on white bread were examined in terms of mixograph, pH, fermentation rate, TPA, crumbScan, colorimeter, sensory evaluation, and the hardness of bread through different storage times (0, 1, 2, 3 days), and texture as measured by texture analyzer. According to mixograph, the control (CON), black beer stout (BOB) and Asahi beer (AOB) but not max beer (MOB) were found to be proper between 3 and 5 minutes of peak time. All samples for peak value were at the level of over 60%. AOB showed the highest specific volume, and was the lowest in hardness (i.e. highest in softness) by TPA and storage days. In sensory evaluation, the difference test showed that AOB had the best volume, springiness, moistness, and softness. Moreover, in an overall preference test AOB scored the highest points in texture, flavor, taste, and overall acceptance.

• 한국환경과학회지
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• 제11권4호
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• pp.339-346
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• 2002

Physico-chemical properties of the activated sludges(Suyoung and Changlim treatment plant), such as SVI(sludge volume index), absorbance, specific surface area, and specific resistance using Buchener funnel test were investigated with changing anaerobic storage time. This experimental condition was found that it was possible to estimate a linear relationship between their parameters such as specific surface area specific resistance, and sludge volume index(SVI). The specific surface area and the specific resistance to filtration of the activated sludges of Suyoung and Changlim treatment plant were found as 123.6~136.6$m^2$/gDS and 41.5~44.9$m^2$/gDS(dry solid), and 1.09$\times$10$^{14}$ ~5.48$\times$10$_{14}$ m/kg and 1.05$\times$10$^{14}$ ~2.48$\times$10$^{14}$ m/kg, respectively. The results gave a good linear relationship between the specific surface area and the specific resistance, r=2.25$\times$10$^{12}$ s-8.10$\times$10$^{13}$ ($R^2$=0.8885) at Suyoung treatment plant and r=1.26$\times$10$^{13}$ s-4.75$\times$10$^{14}$ ($R^2$=0.8756) at Changlim treatment plant.

• 한국조리학회지
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• 제13권4호
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• pp.211-219
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• 2007

The objective of this study was to investigate the influence of adding Gastrodiae rhizoma powder on quality attributes of sponge cake. The cake was made with various Gastrodiae rhizoma powder concentration(0.5%, 1%, and 1.5%) added, and it was stored for 5 days at three different temperatures(5, 15, and $25^{\circ}C$). By analyzing the mixogram data of wheat flour-Gastrodiae rhizoma powder composite flour, the ascending angle of the samples containing Gastrodiae rhizoma powder was increased and the descending angle had upper values compared with that of control as the Gastrodiae rhizoma powder addition concentration was increased. The loaf volume of 0.5% Gastrodiae rhizoma powder slightly increased by 5.1% but those of 1% and 1.5% were slightly decreased compared with that of the control. Crumb firmness of the control showed relatively high value compared with those($5{\sim}6\;N$) of other samples containing Gastrodiae rhizoma powder regardless of storage temperature and storage period, and the firmness after 5 day storage at $5^{\circ}C$ showed the highest value(about 9.3 N). Sensory evaluation attributes of sponge cakes did not show significant difference by Gastrodiae rhizoma powder addition up to concentration of 1.5%.

• Journal of the Optical Society of Korea
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• 제6권4호
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• pp.172-179
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• 2002

Like the conventional digital storage systems, volume holographic memory can be deteriorated by burst errors due to its high-density storage characteristics. These burst errors are used byoptical defects such as scratches, dust particles, etc. and are two-dimensional in a data page. To deal with these errors, we introduce some concepts for describing them and propose efficient two- dimensional interleaving schemes. The schemes are two-dimensional lattices of an error-correction code word and have equilateral triangular and square structures. Using these structures, we can minimize the number of code words that are interleaved and improve the efficiency of the system. For large size burst errors, the efficient interleaving structure is an equilateral triangular lattice. However, for some small size burst errors, it is reduced to a square lattice.