• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.10
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• pp.967-974
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• 2009

Experiments were conducted to measure the heat flux and temperature over a protuberance, using an impulse hypersonic shock tunnel-coaxial thermocouples and a blowdown hypersonic wind tunnel-temperature sensitive paints(TSP). Experimental data were compared with the heat flux data using a blowdown hypersonic wind tunnel-heat flux gauges and it was confirmed data sets agreed well. The measured heat flux is large when the height of the protuberance is large. Also, the heat flux measurements at the upper positions are larger than at the lower positions. For high protuberances, a severe jump in the heat flux is observed, from about 0.6~0.7 of the height of the protuberances. However, when the protuberance is sufficiently short, a rise in the heat flux is rarely observed as the protuberance is submerged totally under the separation region.

• Archives of Craniofacial Surgery
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• v.17 no.1
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• pp.25-27
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• 2016

Cutaneous horns are conical, circumscribed protuberances formed by densely layered keratin. These lesions originate from basal keratinocytes and may manifest as benign, premalignant, or malignant cutaneous pathology in chronically sun-damaged areas. Complete surgical excision with histologic examination is needed for potential malignancy. In this report, we describe two elderly women presenting with solitary facial cutaneous horns, which were respectively diagnosed as actinic keratosis and squamous cell carcinoma.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.363-366
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• 2003

In nanomachining processes, chemical effects are more dominant factor compared with physical deformation. For example, during the nanoscratch on a silicon surface in the atmosphere, micro protuberances are formed due to the mechanochemical reaction between the diamond tip and the surface. On the contrary, in case of chemically stable materials, such as ceramics or glasse, the surface protuberance are not formed. The purpose of this study is to understand effects of the mechanochemical reaction between tip and surfaces on deformation behaviors of hard-brittle materials. Nanometerscale elasoplastic deformation behavior of single crystal silicon (100) was characterized with the surface protuberance phenomena, and compared with that of borosilicate (Pyrex glass 7740).

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.6
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• pp.721-727
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• 2003

Freezing of turbulent water flow between two horizontal cooled parallel plates with the separated region has been investigated experimentally. The flow separation was induced by vertical plates (two-dimensional plates) situated at the inlet of the rectangular channel. The degree of flow separation was varied by employing vertical thin plates with various heights. Three kinds of the vertical plates with 8.0, 9.8 and 12.5 mm in height were utilized. The Reynolds number and cooling temperature ratio were ranged from $3.45\times10^3 to 1.73\times10^4$ and 7.0 to 20.0 respectively, The measurements show that the flow separation influenced remarkably on the local ice formation characteristics. The location of the first ice layer and the average heat transfer at the ice surface were found be correlated as a function of the Reynolds number, the cooling temperature ratio, and the orifice height ratio.

• Journal of Plant Biology
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• v.33 no.2
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• pp.127-134
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• 1990

Three marine species of Cladophora (Cladophoraceae, Chlorophyta) commonly occurred on the coast of Cheju Island, Cladophora conchopheria Sakai, C. gracilis (Griff.) Kutzing and C. wrightiana Harvey were described morphologically, considering their taxonomic characters. C. conchopheria Sakai, specifically growing on the surface of Lunella coronata, is a very minute plant of 550-990 ${\mu}{\textrm}{m}$ in height and has intracuticular adventitious rhizoids borne from the lower portion of the first to fourth segments. C. gracilis occurs on calm habitat and shows a pseudosympodial growth with pectinate branchlets. c. wrightiana always produces protoplasmic protuberances at the node of middle portion of thallus. It grows to 30 cm or more in height and is dark green in subtidal bottom.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.7
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• pp.58-68
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• 1995

Polysilicon capacitors with pyrogenic oxide and TEOX oxide as insulators were fabricated to develop capacitors which can be applied to analog CMOS IC, and the characteristics of the capacitors were compared with each other. The morphology of bottom polysilicon in pyrogenic oxide capacitor is degraded due to the generaged protuberances of the polysilicon grain during oxidataion. The polysilican capacitor with pyrogenic oxide of 57 nm thickness showed that the effective potential barrier height of 0.45 eV is much less than that of MOS capacitor (3.2 eV)when the top electrode is biased with a positive volgate. The morphology of the polysilicon capacitor with TEOS oxide, however, was not degraded during oxide deposition by LPCVD. The polysilicon capacitor with TEOS oxide of 54 nm thickness showed the effective potential barrier height of 1.28 eV when the top electrode is biased with a negative voltage. Therefore, it is concluded that the polysilicon capacitor with TEOS oxide is more applicable to analog CMOS IC than the pyrogenic oxide polysilicon capacitor.

• Animal cells and systems
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• v.9 no.3
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• pp.113-122
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• 2005

A new species of free-living marine draconematid nematode, Dracogalerus koreanus n. sp., is described from the shallow subtidal coarse sediments and various invertebrates of Jeju Island, Korea. This is the first record of this genus from Korea. Dracogalerus koreanus n. sp. is morphologically most similar to D. cryptocephalus (Irwin-Smith) in having similar head shape (rostrum broadly rounded anteriorly) and eight cephalic adhesion tubes, but differs by the small number of rounded protuberances on the ventral side of non-annulated tail end (5 vs 6), small number of posterior subventral adhesion tubes in male (5-6 vs 8), intermingled somatic setae (5-6 vs absent), spicules (slightly curved and relatively thick vs strongly curved and very slender), and higher 'c' value in male (8.8 vs 7.5).

• Electrical & Electronic Materials
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• v.8 no.5
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• pp.564-571
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• 1995

This paper deals with the arc discharge characteristics of kerosene oil as a basic study on electrical discharge machine. Using needle electrode the discharge voltage, discharge current, discharge energy and the shape of discharge crater are measured. In consequence, it becomes clear that the discharge crater(depth, height, diameter) is depending on the discharge energy. Rapid increase in depth, height and diameter of discharge crater was observed during initial discharge, where discharge energy is large. However, rather slow decrease of those values was found when discharge energy is low or N is more than 3. As the ratio of $I_p$$T_on$ increase, the shape of discharge crater gets near circle. The protuberances of the discharge crater were not formed by the melted needle electrode but by the that of work piece.

• Parasites, Hosts and Diseases
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• v.38 no.3
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• pp.173-175
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• 2000

The present study examined postmetacercarial changes in the excysted metacercariae of Echinostoma caproni maintained in the defined medium Mixture 199 plus 20% calf serum for 7 days at $41^{\circ}C$. The gas phase was atmospheric air. Each culture was inoculated with 25 excysted metacerariae. Cultures were maintained upright in closed 15 ml plastic centrifuge tubes each containing 10 ml of medium plus 200 units of penicillin/ml and $200{\;}\mu\textrm{g}$ of streptomycin/ml. By 4 days in culture, most metacercariae had voided their excretory concretions. Organisms were clumped or solitary at the bottom of the cultures. Many organisms showed flaring of the oral collar and extension of both the collar and tegumentary spines. By 4 days in culture, posterior protuberances or bumps were noted on many of the organisms and some organisms showed abnormal vesicular growths or blebs at their posterior ends. Some mortality was noted in culture by day 5, but most organisms were still alive when the cultures were terminated on day 7.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.319-328
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• 2018

The morphology, anatomy and reproduction (tetra/bisporic and male) of Lithothamnion japonicum Foslie was studied, using holotype material and materials collected from Korea. Lithothamnion japonicum is characterized based on the presence of encrusting, warty to fruticose thallus, branched or unbranched short and cylindrical protuberances, conical shaped spermatangial conceptacles, branched (dendroid) spermatangial systems formed on floor, walls, and roof of conceptacle chamber, cylindrical shaped spermatangial conceptacle canal, 9-10 cell layered spermatangial conceptacle roof, raised tetra/bisporangial conceptacles without rims, flattened tetra/bisporangial conceptacle pore plate, 16-50 pores on each pore plate, 6-8 rosette cells surrounded by each pore, pore canal lining filaments composed of tetra/bisporangial conceptacle roof, and buried senescent tetra/bisporangial conceptacles completely infilled with relatively large and irregularly arranged calcified sterile cells. In this study, we report a new record of Lithothamnion japonicum from Korean coasts.