• 제목/요약/키워드: Long-term dry storage

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도시유역 CSOs 처리를 위한 저류형시스템 설계용량 산정 (Estimation of Storage Capacity for CSOs Storage System in Urban Area)

  • 조덕준;이정호;김명수;김중훈;박무종
    • 한국물환경학회지
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    • 제23권4호
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    • pp.490-497
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    • 2007
  • A Combined sewer overflows (CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available (which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a continuous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban drainage system used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range $3{\times}DWF$ (dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a decision of storage volume for CSOs reduction and water quality protection.

도시유역 저류형 시스템 설계를 위한 CSOs 산정 (Storm-Water CSOs for Reservoir System Designs in Urban Area)

  • 조덕준;김명수;이정호;박무종;김중훈
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.1199-1203
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    • 2005
  • Combined sewer overflows(CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available(which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a contiunous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban dranage system used analytical Probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics or the subject area using analytical Probabilistic model. Runoff characteristics manifasted the unique characteristics of the subject area with the infiltration capacity of soil and recovery of depression storage and was examined appropriately by sensitivity analysis. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range 3xDWF(dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a dicision of storage volume for CSOs reduction and water quality protection.

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Cryopreservation and low-temperature storage of seeds of Phaius tankervilleae

  • Hirano, Tomonari;Godo, Toshinari;Miyoshi, Kazumitsu;Ishikawa, Keiko;Ishikawa, Masaya;Mii, Masahiro
    • Plant Biotechnology Reports
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    • 제3권1호
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    • pp.103-109
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    • 2009
  • In this study we established reliable methods for conservation of seeds of Phaius tankervilleae as an orchid genetic resource. The seeds, which were dehydrated to 5% water content and preserved at $4^{\circ}C$, showed no decrease in viability and germinability after three months. After storage for six months, however, the seeds showed a drastic decrease in germinability, even though survival rate was high. For long-term preservation of seeds of P. tankervilleae, cryopreservation is applied to the freshly harvested seeds. When the seeds were cryopreserved by the vitrification method for up to 12 months there was no apparent deterioration effect of storage time. These results indicate that cryopreservation by the vitrification method is useful for long-term conservation of P. tankervilleae seeds, which are difficult to preserve for more than three months under dry and low-temperature conditions.

Storage stability of dry-aged beef: the effects of the packaging method and storage temperature

  • Choe, Juhui;Kim, Kwan Tae;Lee, Hyun Jung;Oh, Jungmin;Kim, Hyun Cheol;Park, Bumjin;Choi, Yang Il;Jo, Cheorun
    • 농업과학연구
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    • 제45권2호
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    • pp.211-218
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    • 2018
  • Different packaging methods and storage temperatures were tested to determine the storage stability of beef dry-aged for 21 days based on microbial, physicochemical, and sensory qualities. After completion of the dry aging, the dried surface of beef sirloin was trimmed off, and the beef was packaged using two different methods (oxygen-permeable wrap or vacuum packaging) and stored at different temperatures ($3{\pm}2^{\circ}C$ or $-23{\pm}2^{\circ}C$) for 0, 7, 14, or 21 days. Lipid oxidation and the sensory quality of the dry-aged beef were not affected by the packaging method and storage temperature during storage. No microbial growth was observed over the storage period in the vacuum-packaged dry-aged beef, regardless of the storage temperature. However, dry-aged beef in the oxygen-permeable wrap packaging showed microbial spoilage with 8.82 log CFU / g at day 7 of the refrigerated storage. The vacuum-packaged dry-aged beef showed the lowest values (p < 0.05) in $a^*$ and chroma at days 14 and 21 at $3^{\circ}C$, and days 7 and 14 at $-23^{\circ}C$, respectively. Therefore, it is recommended that dry-aged beef with wrap packaging stored in refrigerated conditions should be consumed as quickly as possible due to microbial growth. For long-term storage, dry-aged beef should be frozen because freezing can extend the color stability up to day 21 of storage without adverse effects on the hygienic or meat quality aspects of dry-aged beef.

사일리지의 연간급여와 사료성분의 안정성 (Year-long Feeding of Silage and Stability of Feed Quality)

  • 성경일
    • 한국초지조사료학회지
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    • 제12권1호
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    • pp.19-25
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

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사일리지의 연간급여와 사료성분의 안정성 (Year-long Feeding of Silage and Stability of Feed Quality)

  • 성경일
    • 한국초지조사료학회지
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    • 제12권1호
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    • pp.19.1-19.1
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    • 1992
  • This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

REVIEW AND FUTURE ISSUES ON SPENT NUCLEAR FUEL STORAGE

  • Saegusa, T.;Shirai, K.;Arai, T.;Tani, J.;Takeda, H.;Wataru, M.;Sasahara, A.;Winston, P.L.
    • Nuclear Engineering and Technology
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    • 제42권3호
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    • pp.237-248
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    • 2010
  • The safety of metal cask and concrete cask storage technology has been verified by CRIEPI through several research programs on demonstrative testing for the interim storage of spent fuel. The results have been reflected in the safety requirements for dry casks issued by NISA/METI (Nuclear and Industrial Safety Agency, Ministry of Economy, Trade and Industry) of the Japanese government. On top of that, spent fuel integrity has been studied by the Japan Nuclear Energy Safety Organization (JNES). This paper reviews these research programs. Future issues include the long-term integrity of cask components and high burn-up spent fuel.

복식유물 오구의 선택적 제거를 위한 세척방법 및 장기간 보관에 따른 오구 변화 -혈액오구를 중심으로- (Cleaning Method for Selective Removal of Stains from Historic Textiles and Stains Change by Long Period Storage -Focused on Blood Soil-)

  • 노의경;유효선;채정민
    • 한국의류학회지
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    • 제41권2호
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    • pp.341-351
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    • 2017
  • This study evaluates a cleaning method to maintain and minimize the change of blood soil for the selective removal of stains from textiles with historical significance and special meaning. Cotton and silk fabrics were soiled with blood, aged artificially and then washed by wet cleaning or dry cleaning (water, nonionic surfactant; Triton, natural surfactant; saponin, organic solvent; n-Decane). The washed fabrics were stored at room temperature for four years. The change of the blood soil was evaluated by SEM, weight, thickness, and color differences. Subsequently, the shape and the amount of blood adsorption on the fabric varied depending on fiber type and fabric structure characteristics; in addition, long term storage affected changes to blood soil. It was difficult to remove artificially aged blood soil from fabrics by wet or dry cleaning. However, the changes of the blood soil by these cleanings can be explained by the changes on SEM, weight, thickness and fabric color. The changes (especially color) showed over time. Wet cleaning showed that the changes of those factors were slightly lower than those by dry cleaning.

Sensitivity Analysis of Thermal Parameters Affecting the Peak Cladding Temperature of Fuel Assembly

  • Ju-Chan Lee;Doyun Kim;Seung-Hwan Yu;Sungho Ko
    • 방사성폐기물학회지
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    • 제21권3호
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    • pp.359-370
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    • 2023
  • The thermal integrity of spent nuclear fuels has to be maintained during their long-term dry storage. The detailed temperature distributions of spent fuel assemblies are essential for evaluating the integrity of their dry storage systems. In this study, a subchannel analysis model was developed for a canister of a single fuel assembly using the COBRA-SFS code. The thermal parameters affecting the peak cladding temperature (PCT) of the spent fuel assembly were identified, and sensitivity analyses were performed based on these parameters. The subchannel analysis results indicated the presence of a recirculation flow, based on natural convection, between the fuel assembly and downcomer region. The sensitivity analysis of the thermal parameters indicated that the PCT was affected by the emissivity of the fuel cladding and basket, convective heat transfer coefficient, and thermal conductivity of the fluid. However, the effects of the wall friction factor of the canister, form loss coefficient of the grid spacers, and thermal conductivities of the solid materials, on the PCT were predominantly ignored.

Terminal solid solubility of hydrogen of optimized-Zirlo and its effects on hydride reorientation mechanisms under dry storage conditions

  • Kim, Ju-Seong;Kim, Tae-Hoon;Kim, Kyung-min;Kim, Yong-Soo
    • Nuclear Engineering and Technology
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    • 제52권8호
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    • pp.1742-1748
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    • 2020
  • TSSD, TSSP, and TSSP2 of hydrogen for optimized-Zirlo (Zirlo™) alloy were measured by DSC in the range of 53-457 wppm. Solvus curves of the TSSs are derived and proposed in this study. The results show that the temperature gap between TSSD and TSSP solvus lines of Zirlo™ are similar to those of other zirconium alloys, but another gap between the TSSD and TSSP2 line differs significantly. In particular, the TSSP2 solvus line becomes closer to the TSSD solvus line than to TSSP unlike Zircaloy-4, so ΔTTSSD-TSSP2 of Zirlo™ decreases with decreasing temperature. This implies that hydride reorientation can take place more significantly in Zirlo™ than in Zircaloy-4, and the limited temperature variation of 65 ℃ during the vacuum drying and the cooling-down process may not be sufficient to prevent the triggering of hydride reorientation in Zirlo™ cladding under long-term dry storage.