• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.133-143
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• 2019

Various problems regarding the wet floor method such as its complicated process and waste of thermal storage have been raised, but the usage of dry floor recommended for long-life housing has declined due to lack of confidence on the performance of dry floor. The purpose of this study is to secure the credibility of dry floor. Under this purpose, this study considered precedent studies and established directions to secure the performance of long-life housing infill, and thus, 9 performance items (Impact sound, Smoothness, thermal comfort, sensation hardness while walking, falling safety, impact resistance, local compression load, local strength and strain at heating) were drawn. In addition, the experiment was carried out for 5 performances except for legal performance, some dry floor performances and whole spatial performance. As a result, an appropriate result from all performances except was obtained. The performance of dry floor was verified for each item from these results and it is expected to use such results as basic data on dry floor in the future.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.4
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• pp.483-491
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• 2004

The purpose of this study is to develop an ozone passive sampler and to evaluate its performance p-Acetamidophenol using as the reagent for ozone reacts specifically with the ambient ozone to produce a fluorescence material (p-acetamidopheonl dimer). The volume of absorbent solution and the extraction time determined at suitable conditions for measuring ozone were 100$\mu$L and 60 min, respectively. The changes of fluorescence were observed with incresing the storage period of passive samplers in ambient air. but the cool storage in a refrigerator did not remarkably influence the increase of fluorescence. The measurement for the precision oi the passive sampling was carried out with duplicate measurement of passive samplers. The intra-class correlation coefficients of passive samplers using dry and wet filters were 0.992 and 0.962, respectively The results from field validation tests indicated practical agreement (dry filter: r=0.963, wet filter: r=0.995) between the passive sampler and an UV photometric $O_3$ analyzer. The limit of quantification of ozone passive samplers with sampling time of 8 hr (wet filter) and 24 hr (dry filter) were 8.0 ppb and 2.7 ppb, respectively.

• Nuclear Engineering and Technology
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• v.52 no.8
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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 ΔT_TSSD-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.

• Food Science of Animal Resources
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• v.39 no.6
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• pp.934-942
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• 2019

Previous studies on dry aged beef, which substantially increases the value of low-grade raw beef and non-preferred cuts, are currently limited to the observation of aged beef changes in laboratory settings or under particular aging conditions, whereas the factors influencing aging have so far been underexplored. Herein, we attempt to establish a technique for distinguishing between fresh and aged beef by observing changes in quality during beef aging. Specifically, we analyzed the effect of time on the quality of aged beef sourced from three Korean manufacturers and identified quality indicators that can be used to distinguish between fresh and aged beef, regardless of supplier. Storage/trimming/aging/cooking losses, moisture/fat/protein/collagen contents, and water holding capacity were tested as potential indicators, among other parameters. As a result, the quality of dry aged beef was shown to be supplier-dependent, which made the identification of factors for the above origin-independent discrimination difficult. Nevertheless, as storage loss, water holding capacity, and cooking loss significantly changed with dry aging time in all cases, these parameters were concluded to be potentially suited for discrimination purposes. The insights gained in this work may help promoting further research in this field and contribute to the development of a standard for consistent aged beef production.

• Animal Bioscience
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• v.36 no.5
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• pp.797-809
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• 2023

Objective: Many scientists have investigated solutions to reduce microbiological risks in dry-aged meat after the dry-aging technology was revived for high quality and value-added premium meat product in the market. This study aimed to investigate the effect of scoria powder in onggi (Korean earthenware) on the meat quality of pork loins during 21 days of dry aging and to elucidate its mechanism of action. Methods: The pork loins were randomly divided into three groups: aged in vacuum-packaging, onggi containing red clay only (OR), and onggi containing 30% red clay and 70% scoria powder (OS). Microbial analyses (total plate count and Lactobacillus spp.) and physicochemical analyses (pH, shear force, volatile basic nitrogen [VBN], water activity, 2-thiobarbituric acid reactive substances, water content, water holding capacity, cooking loss, and color analysis) of aged meat were conducted. Far-infrared ray emission, quantification of immobilized L. sakei and microstructure of onggi were investigated to understand the mechanism. Results: On day 21, the meat aged in OS exhibited lower pH, shear force, VBN, and water activity than those aged in OR, along with an increase in the number of Lactobacillus spp. OS had a smaller pore diameter than OR, implying lower gas permeability, which could promote the growth of L. sakei. Conclusion: OS improved the microbiological safety and storage stability of pork loin during dry aging by increasing number of Lactobacillus spp. possibly due to low permeability of OS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.382-388
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• 1994

For the comparision of the differences in dry matter weight and the chemical composition of soybean seeds in relation to utilization styles and storage durations, the seed coats and cotyledons including embryo axis separated from the seeds of 3 recommended cultivars stored for 3 years and of 5 recommended cultivars and 2 local varieties with black seed coat and green cotyledons were observed in dry weight, germination percentage, protein, oil, soluble sugar, oilgosaccharide, and starch. In the seeds stored for 3 years, dry weight and germination rate were decreased distinctively. This decrease of seed dry matter resulted from the decrease of the cotyledon weight, and the ratio of seed coat to whole seed was increased. For the change of chemical compositions by the decrement of seed dry weight during the storage, protein, oil, and carbohydrate contents of the seed coat were decreased, and protein content of the cotyledon was markedly decreased in the seeds stored for 3 years. The ratio of seed coat to whole seed was higher in small seed than large seed cultivars. In the local varieties, protein and oil contents were 43.59% and 18.25% in the cotyledons, respectively, which were lower than those of recommended cultivars. But starch and sugar contents were 5.70% and 11.58%, respectively, which were higher than those of recommended cultivars. Sucrose, raffinose and stachyose contents were also higher in the cotyledon of the local varieties.

• Journal of computational fluids engineering
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• v.21 no.2
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• pp.47-53
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• 2016

This study investigated natural convection flow behavior in airflow path designed in concrete dry storage cask to remove the decay heat from spent nuclear fuels. Using FLUENT 16.1 code, thermal analysis for natural convection was carried out for three dimensional, 1/4 symmetry model under the normal condition that inlet ducts are 100% open. The maximum temperatures on other components except the fuel regions were satisfied with allowable values suggested in nuclear regulation-1536. From velocity and temperature distributions along the flow direction, the flow behavior in horizontal duct of air inlet and outlet duct, annular flow-path and bent pipe was delineated in detail. Theses results will be used as the theoretical background for the composing of airflow path for the designing of passive heat removal system by understanding the flow phenomena in airflow path.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.4
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• pp.503-516
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• 2023

A transfer cask serves as the container for transporting and handling canisters loaded with spent nuclear fuels from light water reactors. This study focuses on a cylindrical transfer cask, standing at 5,300 mm with an external diameter of 2,170 mm, featuring impact limiters on the top and bottom sides. The base of the cask body has an openable/closable lid for loading canisters with storage modules. The transfer cask houses a canister containing spent nuclear fuels from lightweight reactors, serving as the confinement boundary while the cask itself lacks the confinement structure. The objective of this study was to conduct a structural analysis evaluation of the transfer cask, currently under development in Korea, ensuring its safety. This evaluation encompasses analyses of loads under normal, off-normal, and accident conditions, adhering to NUREG-2215. Structural integrity was assessed by comparing combined results for each load against stress limits. The results confirm that the transfer cask meets stress limits across normal, off-normal, and accident conditions, establishing its structural safety.

• Plant Resources
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• v.6 no.1
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• pp.53-56
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• 2003

To develop optimal storage method of root of Anemarrhena Rhizome, which has been grown as major cultural herbal medicine material, root of Anemarrhena Rhizome was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The rot ratio of root during the storage period was not significantly different among packing materials but was significantly different among sealing conditions. Conclusively vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Anemarrhena Rhizome.

• Plant Resources
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• v.5 no.2
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• pp.114-117
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• 2002

To develop optimal storage method of root of Peucedani Radix, which has been grown as major cultural herbal medicine material, root of Peucedani Radix was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between packing materials but was significantly different between sealing conditions. Conclusively vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Peucedani Radix.