• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.133-134
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• 2006

A cylindrical capacitive displacement sensor (CCS) was developed and applied for monitoring end milling processes. Dynamic characteristics of a spindle-assembly were measured using the CCS and a designed magnetic exciter. The technique to extract the spindle displacement component caused only by cutting from the measured signals using the CCS was proposed in the paper. Using CCS signals and FRF (Frequency Response Function) derived from dynamics of the spindle tool system, dynamic cutting forces are estimated quantitatively.

• Animal Systematics, Evolution and Diversity
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• v.29 no.2
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• pp.144-151
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• 2013

Two marine hypotrichous ciliates, Anteholosticha petzi and Ponturostyla enigmatica, were collected from the Yellow Sea and the Korea Strait, respectively, and described using live observation and protargol-impregnated specimens. Furthermore, the nuclear small subunit ribosomal RNA gene of each was sequenced and compared to previously annotated sequences retrieved from the GenBank. Anteholosticha petzi is characterized by 3 frontal cirri (FC), 2 frontoterminal cirri (FTC), 8-12 transverse cirri (TC), 1 buccal cirrus (BC), 9-12 midventral pairs (MP), 3 bipolar dorsal kineties (DK), and 3 types of colorless cortical granules. Ponturostyla enigmatica is characterized by 8 FC, 5 ventral cirri (VC), 5-7 TC, 6-7 marginal rows (MR) on each side, 4 complete and 2-3 partial DK, and greenish cortical granules. This is the first identification and description of these 2 species, A. petzi and P. enigmatica, in South Korea.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.635-638
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• 2005

An energy recovery sustaining driver with zero current switching to reduce switching losses and EMI is presented in this paper. The driver with designed snubber circuits reduces ringing voltage significantly on PDP so that the voltage rating of MOSFETs can be lower as well to reduce the cost of switches.

• Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.209-211
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• 2008

Heterotrophic dinoflagellate Pfiesteria piscicida (Dinophyceae) has been claimed to produce potent ichthyotoxins that cause disorientation and eventually death of fish and other marine animals. A real-time PCR probe targeting for SSU rRNA gene was used for detection of P. piscicida in Chinhae Bay, Korea. PCR inhibitors were successfully removed by dilution of template DNA. Positive detections were shown from surface water samples indicating the presence of P. piscicida in Chinhae Bay.

• Mycobiology
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• v.32 no.4
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• pp.179-185
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• 2004

Arbuscular mycorrhizal fungi were observed in Botrychium ternatum native in Korea. The partial small subunit(SSU) of ribosomal DNA gene from the fern roots was amplified with primers AM1/NS31. Nucleotides sequence analysis of the clones revealed that two fragments were close to Glomus proliferum and G. sinuosum. The other three DNA fragments were close to those of G. proliferum with the relatively low similarities($92{\sim}95%$) and speculated to be originated from three different species of Glomus(GLA006, GLA016, and GLA032). Five different nucleotide sequences close to three AM fungal species were found in the roots of B. ternatum native in Korea.

• Mycobiology
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• v.49 no.4
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• pp.297-307
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• 2021

A cordycipitoid fungus infecting Hepialidae sp. in Nepal was supposed to be identical to Cordyceps liangshanensis, originally described from southwestern China, and thus, transferred to the genus Metacordyceps or Papiliomyces in previous studies. However, our multi-gene (nrSSU-nrLSU-tef-1α-rpb1-rpb2) phylogenetic and morphological studies based on the type specimen and additional collections of C. liangshanensis revealed that the fungus belongs to the genus Ophiocordyceps (Ophiocordycipitaceae). Therefore, a new combination O. liangshanensis was made, and a detailed description of this species was provided.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.425-431
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• 2021

New species of arbuscular mycorrhizal fungi (Glomeromycota), Acaulospora jejuensis, was isolated from rhizosphere soils of Miscanthus sinensis in the grassland in Jeju Island of Korea. The species was identified using the morphological characteristics of the spores and the molecular phylogenetic analysis using partial DNA sequences from small subunit rDNA (SSU), internal transcribed spacer (ITS), and large subunit rDNA (LSU). Phylogenetic analysis placed the fungal species in a distinct clade within genus Acaulospora. Also, the species exhibited the morphological characteristics distinct from the other members of the genus. Therefore, Acaulospora jejuensis was described as a novel species from Korea.

• Mycobiology
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• v.49 no.2
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• pp.133-141
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• 2021

A new fungus, Ophiocordyceps alboperitheciata, parasitic on the larva of Noctuidae (Lepidoptera) was identified from a survey of entomopathogenic fungi in Kunming Wild Duck Forest Park, Yunnan Province, China. It can be primarily distinguished from relatives by its longer fertile parts, sterile tips, superficial perithecia, narrower asci, and smaller septa of ascospores. As revealed from phylogenetic analyses inferred from nrSSU, nrLSU, tef-1α, rpb1, and rpb2 sequence data, O. alboperitheciata belongs to the Hirsutella citriformis clade in the genus Ophiocordyceps of Ophiocordycipitaceae, and forms a separated clade from other related species. The uniqueness of the taxon is significantly evidenced by both molecular phylogeny and morphology. Furthermore, the interspecific relationships in the H. citriformis clade are discussed.

• Journal of fish pathology
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• v.34 no.1
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• pp.47-53
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• 2021

Scuticociliates are one of the serious parasitic threats faced by the marine aquaculturists worldwide. To date, Uronema nigricans, Philasterides dicentrarchi, Miamiensis avidus, Uronema marinum, and Pseudocohnilembus persalinus have been reported as the important culprit species causing scuticociliatosis in fish. The present paper reports the finding of an additional scuticociliate isolate from the gill of diseased olive flounder Paralichthys olivaceus in Korea. Based on the morphological characteristics, a scuticociliate in this study was identified as Paranophrys marina. Phylogenetic analysis placed P. marina as a sister lineage to three species of Pseudocohnilembus and Mesanophrys carcini within the order Philasterida.

• Mycobiology
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• v.50 no.3
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• pp.172-180
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• 2022

The new genus and species, Jejulea byssolomoides, is described from Jeju Island, Korea. This lichen is characterized by saxicolous, crustose, pale greenish-gray, partly finely filamentous, matt, smooth thallus, prominent convex brown to dark brown ascomata with a concolorous margin constricted at the dark brown base, 300-800 ㎛ diameter, 200-250 ㎛ high, without a distinct proper margin, adhering to the substratum ending in a minute byssoid white external part of cylindrical cells, fusiform 3-5 septate ascospores (17-23 × 4-5 ㎛). Phylogenetic analyses using ITS and mtSSU sequences place Jejulea in the Pilocarpaceae (Lecanorales). The new taxon is closely related to Byssoloma, a cosmopolitan group of foliicolous lichens, which is most diverse in the tropics. Like Byssoloma, Jejulea also forms a byssoid apothecial margin.