• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.18 no.1
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• pp.17-23
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• 1982

The corrosion loss of the shell plates and the bulkead plates of the oil tankers, nationalities of which belong to korea are determined and analyzed. The thickness of the plates are determined by use of the ultrasonic thickness meters at the check points set along the fore and aft line and the perpendicular to it. Difference between the original thickness and the determined one are given as the corrosion loss at the present age. 1. On the shell plates (1) The total mean of the corrosion loss shows the greatest value on the load water line in every age classes of the vessels. (2) The total mean of the corrosion loss on the fore and aft line shows little difference, even though it is slightly greater at the fore part, in every age classes of the vessels. (3) The corrosion loss along the perpendicular grows greater in the order of upper bilge line, light water line, freeboard line and load water line at 16 ages of the vessels, and the loss changes in the order of light water line, upper bilge line, freeboard line and load water line at 20 ages of the vessels. (4) The total mean of the corrosion loss along the light water line and upper and lower water line shows the greatest value on the fore part. That along the freeboard line and the load water line shows the greatest value on the midship part and on the after part, respectively. 2. On the bulkhead plates (1) The total mean of the corrosion loss shows the greatest value on the top part at the every age classes of the vessels. (2)The corrosion loss along the perpendicular grows greater in the order of the lower, center and upper part at every age classes of the vessels. (3) The total mean of the corrosion loss at the top part grows greater in the order of the transverse bulkhead of the side oil tank, that of center oil tank, longitudinal bulkhead of center oil tank, and transverse bulkhead of side water tank at the 20 ages of the vessels.

• Journal of Plant Biology
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• v.34 no.1
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• pp.67-75
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• 1991

Anatomical study of the secondary xylem in Malvales plants, including four families, five genera and ten species grown in Korea, was carried out to elucidate relationship among genera or families in the order. Wood of Elaeocarpus is diffuse porous and shows angular vessels in radial multiples of 2-14 cells and a few apotracheal or paratracheal parenchyma. Tiliaceous genera have diffuse porous wood, vessels in solitary distribution and apotracheal parenchyma of sinuous scalariform uniseriate band. In the family, Tilia shows angular vessel. noded and tile-like cell in ray and storied tissue but Grewia has circular vessel. Hibiscus shows ring porous wood, circular solitary vessel and biseriate band of apotracheal and paratracheal parenchyma. Firmiana shows ring porous wood, circular solitary vessel and confluent parenchyma. Many starch grains appear in ray and axial parenchyma. Judging from arrangement, shape, length and diameter of vessel element and angle of end wall to vessel axis, and arrangement and shape of axial parenchyma, the lines of specialization in these genera are from primitive Elaeocarpaceae through less primitive Tiliaceae and less advanced Malvaceae to advanced Sterculiaceae.iaceae.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.45-48
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• 1984

Ion-pair reverse phase HPLC techniques were used to compare the contents of IAA and IAAsp in the embryogenic and non-embryogenic calli derived from ginseng (Panax ginseng C.A. Meyer) root tissues. The contents of IAA and IAAsp of the embryogenic callus were much higher (7 to 18 X respectively) than those of non-embryogenic callus. There is a distinct fluorescent peak of an unknown component in the HPLC profile of the extract for indolic compounds from non-embryo-genic callus. This distinct difference may be employed as a promising parameter to screen the culture pieces for obtaining the calli with high potential for embryoid formation.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.98-105
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• 2021

Understanding the migration patterns and habitats of juvenile birds during the post-fledging stage is very important for conservation and management of individuals. The Chinese Egret is an internationally protected species. During the wintering season, they inhabit South-East Asia, such as the Philippines, Malaysia, and Taiwan, and breed in China, Russia, and uninhabited islands on the west coast of Korea. IIn this study, we attached a GPS telemetry tracking device to six juvenile Chinese Egrets breeding on Chilsan Archipelago in 2018 and 2019 to identify habitats by analyzing the home range during the post-fledging stage in the summer season. The individual CE1801 moved north and then returned to the Yeonggwang Baeksu tidal flat area, and CE1802 and CE1803 migrated north and inhabited Taean-gun. In 2019, CE1901 showed a similar pattern to CE1801, and CE1902 migrated southward to the Wando-gun area, while CE1903 moved south to the Sinan-gun area then returned to the Yeonggwang Baeksu tidal flat area, showing KDE 50%. The study results confirmed that the Chinese Egret moved broadly around the flat tidal area on the west coast to find a stable habitat during the post-fledging stage. Efforts to protect the habitat, such as limiting the development of this area and restricting human access, are necessary.

• Korea Petroleum Association Journal
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• no.3 s.181
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• pp.71-75
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• 1996

• The tire
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• s.72
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• pp.3-7
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• 1977

• The tire
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• s.71
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• pp.12-17
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• 1977

• 해운
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• no.8 s.7
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• pp.46-51
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• 2004

• Journal of Plant Biology
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• v.35 no.3
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• pp.273-281
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• 1992

The origin of the interfascicular cambium from residual meristem can be elucidated by tangential and transverse observation. It is clear that there is structural distinction between interprocambial and interfascicular residual meristem and adjacent parenchyma in both the transverse and tangential view. Consequently, the residual meristem does not convert into parenchyma but, rather, becomes interfascicular cambium. In tangential view, the homogeneous structure of interfascicular residual meristem at an early stage changes gradually into a heterogeneous one at a later stage, with long and short cells from which fusiform and ray initials originate respectively. However, the homogeneous structure of parenchyma adjacent interfascicular residual meristem does not change into a heterogeneous one but remains the same at all stages of development. Therefore, the interfascicular cambium has a direct ontogenetic continuity with the residual meristem, and does not have its secondary origin from differentiated parenchyma. Furthermore, the ontogenetic pattern of the interfascicular cambium is almost the same as that of fascicular cambium.ambium.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.103-112
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• 1995

Six African rice varieties, two each from three types having the characteristics of partially, irregularly, and completely developed abscission layers, were selected and grown 1） to investi-gate the histological differences during the formation and development of the abscission layers and 2） to evaluate the changes in the breaking tensile strength required to detach a grain from its pedicel dur-ing ripening period in relation with developmental stage of the abscission layers. In African rice, the panicle and spikelet grew rapidly from 15 days before heading and almost completely grown in length at five days before heading. The abscission regions were recognized at 15 days before heading. However, any apparently developed abscission layers were not recognized in the lemma side for partially developed abscission layers. A group of parenchymatous cells could be observed sporadically in the abscission layers of the lemma side for irregularly developed ab-scission layers. At ten days before heading, abscission layers consisting of one or two layers of parenchymatous cells were clearly distinguished from neighboring cells due to thickened and lignified cell walls. There were a number of individual parenchymatous cells scattered sporadically in the lemma side of partially developed abscission layers, and a number of grouped parenchymatous cells scattered randomly in the lemma side of irregularly developed abscission layers. At two weeks after heading, the grains became almost fully filled. The cracking of abscission layers between rachilla and pedicel was observed, and the breaking tensile strength required to detach a grain from its pedicel was as low as that at harvest time.