• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.577-583
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• 2010

In this study, the effect of void formation resulting from gas hydrate dissociation or loss of some particles within soil structure on the strength of soil is examined. Beag-ma river sands with uniform gradation were used to simulate a gas hydrate bearing or washable soil structure. Empty capsules for medicine are used to mimic large voids, which are bigger than soil particle. Beag-ma river sand was miced with 8% cement ratio and 14% water content and compacted into a shear box. The number and direction embedded into a specimen. After 4 hours curing, a series of direct shear test is performed on the capsule embedded cemented sands. Shear strength of cemented sands with capsules depends on the volume and direction. The volume and direction formed by voids are most important factors in strength. A shear strength of a specimen with large voids decreases up to 39% of a specimen without void. The results of this study can be used to predict the strength degradation of gas hydrate bearing sediments after dissociation and loss of fine particles within soil structure.

• Animal cells and systems
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• v.3 no.4
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• pp.375-383
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• 1999

Gonadal development, gametogenesis, reproductive cycle, and first sexual maturity of Reishia clavigera were investigated monthly from July 1998 to June 1999 through cytological and histological observations. R. clavigera had separate sexes, and was an internal fertilizer. The ma1e penis was located near the two tentacles. The ovary and testis were composed of a great number of oogenic lobules and spermatogenic tubules, respectively. The size of ripe oocyte ranged from 130 to 140 ${\mu}$m in diameter. The peripheral cytoplasm of the germinal vesicle of the ripe oocyte in many cases were surrounded by smaller yolk granules, while the eccentric cytoplasm was occupied with larger ones. The reproductive cycle of R. clavigera could be classified into five successive stages: early active, late active, ripe, spawning, and recovery. Spawning of females occurred from early July to August when the seawater reached above 24.8$^{\circ}C$. Spawning of males occurred from early June to August in the water above 22.8$^{\circ}C$. Minimum size for sexual maturity of both sexes was above 10.0 mm in shell height. Each egg capsule was a cylinder or spindle in shape, 4-6 mm in length and 1-2 mm in width. Colors of newly spawned egg capsules showed yellowish white or pale yellow, while those with veliger larvae showed pale black, and released larvae or dead egg capsules showed black violet. The fecundity in an egg capsule ranged from 70 to 91 eggs (mean＝80.28 eggs).

• Korean Journal of Plant Taxonomy
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• v.44 no.4
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• pp.238-241
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• 2014

A new species, Juncus baekdusanensis M. Kim (Juncaceae), has been named and described from Mt. Baekdu of the Korean peninsula. Juncus baekdusanensis shares several characters (terete leaf blades with leaf sheath auricles, between 1 and 2 flowered inflorescences, and 2 bracteoles) with its related species J. tenuis Willd. It is, however, distinct from J. tenuis which have 1-flowered inflorescences, green perianth, lanceolate perianth segments, acuminate perianth apexes, small capsules, and lowland grassland habitats by having 2-flowered inflorescences, reddish green perianth, ovate perianth segments, acute perianth apexes, large capsules, and highland swamp habitats.

• Korean Journal of Plant Taxonomy
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• v.43 no.3
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• pp.168-170
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• 2013

A new species, Euonymus baekdusanensis M. Kim (Celastraceae), has been named and described from Mt. Baekdu of the Korean peninsula. Euonymus baekdusanensis shares several characteristics (4-merous flowers, 4-angled capsule, warted branches and twigs, etc.) with its related species E. verrucosus Scopoli. It is, however, distinct from E. verrucosus which have small oblong leaves (6-7 cm), short petioles (1-2 mm), and small capsules (6-8 mm) by having large elliptical leaves (11-13 cm), long petioles (6-8 mm), and large capsules (12-15 mm).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.369-370
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• 2006

During demonstrations of a process conditioning spent nuclear fuels, it is necessary to transport and handle Spent fuel road cuts from Post Irradiation Examination facility to Slitting device in The hot cell. the spent fuel pellets which are highly radioactive materials are separated with its clad and are fed into the next conditioning process. For this, a spent fuel rod, 3.5 m long, is cut by 25 cm long which is suitable length for the decladding process. These rod-cuts are packed into the capsule and are moved to the ACPF(Advanced spent nuclear fuel Conditioning Process Facility). In the ACPF, Once the capsule is unloaded in the ACPF, Capsule is taken out one-by-one and installed on the decladding device. In these processes, the crushed spent fuel pellet can be scattered inside the facilities and thus it contaminate the hot cell. In this paper, we developed the specially designed transportation and storage device for spent nuclear fuel capsules.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.89-93
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• 1999

Stability and gastric acid resistance of Lactobacilli and Bifidobacteria in commercial yogurts were invcstigated. It was noted that there was significant differences of stability and gastric acid resistance among yo-wts. The sutvival of Lactobacilli and B#idohacleria in commercial yogurts decreased as a function of time during storage and showed in the range of $10^7$-$10^8$ cfulml. The lower the pH was, the lower survival of Lactobacillus and B~dobaclerium was observed. The survival of Lactobacillz and Bifidobacteria in three yogurts appeared to be $10^3$-10$^4$ cfuIml. In the case of yogurt containing Bifidobncterza- loaded capsules, the gastric acid resistance of the Rifidobncteria was greatly enhanced and the survival after treatment in a gastric juice for 120 min was over 10' cfulml.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.830-839
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• 2016

Germination of Hemerocallis seeds as influenced by cold stratification at $5^{\circ}C$ (CS) and maturity of seeds evaluated using X-ray imaging has not been well investigated. Seeds of H. lilioasphodelus, H. citrina, H. citrina 'April Flower', and H. minor collected from China and H. thunbergii collected from Korea were germinated at $20^{\circ}C$ without pre-temperature treatment, while H. hongdoensis, H. dumortieri, H. minor, and H. vespertina seeds were treated with CS. Harvesting 'Stella de Oro' capsules at 35-40 days after anthesis yielded mature seeds with well-developed embryo and cotyledons analyzed by X-ray images with a 92% germination in 17 days after sowing. Seeds of H. thunbergii and H. citrina germinated in less than 13 days without CS; two weeks of CS did not accelerate seed germination. Seeds of H. hongdoensis germinated in 24 days when seeds were stored at $25^{\circ}C$ without CS and in less than 27 days when cold stratified. Therefore, 'Stella de Oro' capsules should be harvested at 35-40 days after anthesis to harvest mature seeds. Cold stratification is not required to accelerate seed germination in the Hemerocallis taxa evaluated in this study.

• YAKHAK HOEJI
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• v.41 no.5
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• pp.595-601
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• 1997

The optimal synthesis condition based on the yield of thiamine mononitrate has been attained according to Box-wilson experimental design. The optimal condition was as follows : Molar concentration ratio of $SB1{\cdot}HCL=0.6839$, quantity of $NH_4NO_3=50.09g$, agitation velocity=51.6rpm, reaction temperature=22.8$^{\circ}C$. The stabilities of three kinds of thiamine monosalts(thiamine monoiodide, -monobromide, -monorhodanate) were investigated in sterile solution, compressed tablet and multivitamin capsule, respectively. Assay data are given to show that thiamine monosalts are not significantly higher than that of thiamine mononitrate in sterile solutions and the addition of an acidic stabilizer is unnecessary. The solutions were clear and free of precipitate and didn't discolored after storage at room temperature and 40$^{\circ}C$ for 6 months. The tablets and capsules were assayed initially and at predetermined intervals during storage at room temperature and 40$^{\circ}C$ for 6 months. Thiamine monorhodanate was found to be more stable than other thiamine monosalts in these compressed tablets containing other vitamin of the B complex and the data indicate that thiamine monosalts was similar to that of thiamine mononitrate in the multivitamine capsules.

• Solar Energy
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• v.13 no.1
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• pp.39-48
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• 1993

This empirical paper addresses the phenomena of the contact melting of PCM in horizontal capsules of circular and rectangular cross sections with various aspect ratio. The melting-rate tends to increase as the Stefan number increases. The case of rectangular tube displays larger melting-rate than that of circular tube, and the melting-rate increases as the aspect ratio decreasws for rectangular tubes. In case of circular tube, the effect of natural convection on the melting-rate is 6.1%, 8.6% and 11.2% according to Stefan number 0.0772, 0.1287 and 0.1802 respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.352-359
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• 2003

The present study has been conducted for manufacturing MPCM (microencapsulated phase change material) slurry with in-situ polymerization and proving their applicabilities for tooling system. The surface of MPCM is composed of melamine, while tetradecane, paraffin wax, is centered in the MPCM. The produced capsules are observed by the optical microscope and SEM for superficial shapes. Their thermal properties are measured by DSC. Their size distributions are observed by FA particle analyzer. A narrow size distribution from 1 to 10 ${\mu}{\textrm}{m}$ with 5 ${\mu}{\textrm}{m}$ of average diameter was observed. Melting temperature was 6.7$^{\circ}C$. The durability of MPCM was tested with various types of pump such as centrifugal, peristaltic, and mono pumps. During 10000 cycles the fraction of broken capsules was smaller than 6% for the centrifugal and peristaltic pumps, while bigger value of 8% for the mono pump. A cooling system, which adopted MPCM slurry as a media for transporting cold thermal energy, was designed to investigate the performance of the MPCM. The discharging times of 10 and 20 wt% MPCM slurry were lasted up to 105 and 285 minutes longer, respectively, than the water cooling system.