• Macromolecular Research
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• 제15권1호
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• pp.74-81
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• 2007

A series of photoreactive mesogens based on chalcone were prepared and their morphological behavior and reactivity were studied according to a variable number of alkyloxy tail carbons. The linear ester compounds 3a-h comprised two chalcone units connected to a benzene ring through ester linkages. All linear ester compounds showed enantiotropic liquid crystalline phases. The X-ray diffractograms for the mesophases of compounds 3a-h showed a set of reflections in the small-angle region which consisted of more than three sharp diffraction peaks with d spacings in the ratio of 1:1/2:1/3, confirming the well defined smectic A structures of the compounds. Compounds 3a-h were considered to be bifunctional monomers due to the presence of two photoreactive chalcone groups. Upon UV irradiation, its polymerization proceeded through the [2+2] addition reaction between chalcone units in a stepwise manner. An image pattern was obtained by the photopolymerization of the liquid crystal of the compound (3h) with decyloxy tails through a photomask. The irradiated part became dark while the masked part remained birefringent under polarized optical microscopy, which was ascribed to the production via the UV irradiation of a polymer or a dimer having cyclobutane rings by [2+2] addition, which thereby disrupted the alignment of the molecules.

• 한국발생생물학회지:발생과생식
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• 제15권3호
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• pp.239-247
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• 2011

Spermatogenesis and taxonomic values of mature sperm morphology of in male Septifer (Mytilisepta) virgatus were investigated by transmission electron microscope observations. The morphologies of the sperm nucleus and the acrosome of this species are the cylinder shape and cone shape, respectively. Spermatozoa are approximately 45-50 ${\mu}m$ in length including a sperm nucleus (about 1.26 ${\mu}m$ long), an acrosome (about 0.99 ${\mu}m$ long), and tail flagellum (about 45-47 ${\mu}m$). Several electron-dense proacrosomal vesicles become later the definitive acrosomal vesicle by the fusion of several Golgi-derived vesicles. The acrosome of this species has two regions of differing electron density: there is a thin, outer electron-dense opaque region (part) at the anterior end, behind which is a thicker, more electron-lucent region (part). In genus Septifer in Mytilidae, an axial rod does not find and also a mid-central line hole does not appear in the sperm nucleus. However, in genus Mytilus in Mytilidae, in subclass Pteriomorphia, an axial rod and a mid-central line hole appeared in the sperm nucleus. These morphological differences of the acrosome and sperm nucleus between the genuses Septifer and Mytilus can be used for phylogenetic and taxonomic analyses as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as seen in subclass Pteriomorphia.

• Animal Systematics, Evolution and Diversity
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• nspc9호
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• pp.1-9
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• 2016

Two Spirostomum species were collected from freshwater in Jindo Island, Korea and identified as Spirostomum ambiguum (Muller, 1786) Ehrenberg, 1835 and Spirostomum minus Roux, 1901. This study is the first known morphological record of these two species being found in Korea. The description is based on the observation of living specimens and protargol impregnated specimens. Diagnostics of Spirostomum ambiguum: body size $340-930{\times}45-80{\mu}m$ in vivo; long and slender body with truncated posterior part; macronucleus moniliform with 7-22 nodules; cortical granules irregularly arranged 4-5 rows in between somatic kineties; 24-58 somatic kineties arranged longitudinally; adoral zone of membranelles (AZM) covered about 60-80% of body length. Diagnostics of Spirostomum minus: body size $500-730{\times}35-45{\mu}m$ in vivo; long and slender body with truncated posterior part; macronucleus moniliform with 11-16 nodules; micronucleus 20-37 oval shape; cortical granules regularly arranged 3-4 rows in between somatic kineties; 20-30 somatic kineties arranged longitudinally; AZM covered about 40-50% of body length with 120-150 adoral membranelles.

• Mycobiology
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• 제33권2호
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• pp.69-76
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• 2005

Conidial development of Cordyceps militaris was observed from germinating ascospores and vegetative hyphae through light and scanning electron microscopy (SEM). Ascospores were discharged from fresh specimens of C. militaris in sterile water as well as Sabouraud Dextrose agar plus Yeast Extract (SDAY) plates. We observed ascospore germination and conidial formation periodically. Under submerged condition in sterile water, most part-spores germinated unidirectionally and conidia were developed directly from the tips of germinating hyphae of part-spores within 36 h after ascospore discharge, showing microcyclic conidiation. First-formed conidia were cylindrical or clavate followed by globose and ellipsoidal ones. Germination of ascospores and conidial development were observed on SDAY agar by SEM. Slimy heads of conidia on variously arranged phialides, from solitary to whorl, developed 5 days after ascospore discharge. Besides, two distinct types of conidia, elongated pyriform or cylindrical and globose, were observed in the same slimy heads by SEM. Conidia were shown to be uninucleate with 4,6-diamidino-2-phenylindole staining. Conidiogenous cells were more slender than vegetative hyphae, having attenuated tips. Microcyclic conidiation, undifferentiated conidiogenous hyphae (phialides), polymorphic conidia and solitary, opposite to whorled type of phialidic arrangement are reported here as the characteristic features of asexual stage of C. militaris, which can be distinguished from other Cordyceps species.

• 한국자동차공학회논문집
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• 제17권1호
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• pp.96-104
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• 2009

An anatomically detailed elderly human body model is under development. Using the anthropometric database of domestic nation-wide size survey, SizeKorea, a standard size and shape of 50th %tile elderly was constructed. Through the local recruitment process, a male volunteer with 71 years of age, 163cm of height and 63kg of weight has been selected. The exterior (skin) and interior (skeleton and organ) geometries were acquired from whole body 3D laser scan and various medical images such as CT, X-ray, and Ultrasonic of the volunteer. A particular attention has been paid into the combining process of exterior and interior geometries especially for joint articulation positions since they were measured at different postures (sitting vs. supine). A whole ribcage of PMHS which possessed similar anthropometry and age of standard 50th %tile elderly was prepared and dissected for the precise gauge of cortical rib bone thickness distributions. After completing the morphological construction of elderly human body, the finite element modeling will be processed by meshing elements and assigning mechanical properties to various biological tissues which reflect the aging effect.

• 천문학회지
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• 제26권1호
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• pp.33-45
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• 1993

We have conducted surface photometry of a spiral galaxy NGC4419, by making use of photographic plates in U, B, V and R-bands taken by 105cm Schmidt Camera at Kiso Observatory. Two dimensional surface brightness distributions as well as luminosity profiles along the major axis are examined in detail to decipher the morphological properties of the galaxy. Analysis of the color distributions of NGC4419 shows that B-V and U-B colors remain constant throughout the galaxy with a weak trend of blue bulge in B-V color. The blue bulge might indicate an active star formation in the nucleus of NGC4419. For a quantitative analysis of the luminosity distribution of NGC4419, the observed luminosity profiles are decomposed into bulge and disk components, assuming the bulge component to follow de Vaucouleurs $\gamma^{1/4}-law$ while the disk component is assumed to be exponential. The fitting generally fails at the central part and at the shoulder near r = 15' where bulge and disk components overlap. The failure at the central part cannot be attributed wholly by the seeing disk since the core-radius of the central plateau is much larger than the width of point spread function. The failure at shoulder could be due to the luminosities from the spiral arms.

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권1호
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• pp.178-178
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• 1999

Most stochastic taggers can not resolve some morphological ambiguities that can be resolved only by referring to lexical contexts because they use only contextual probabilities based ontag n-grams and lexical probabilities. Existing lexical rules are effective for resolving such ambiguitiesbecause they can refer to lexical contexts. However, they have two limitations. One is that humanexperts tend to make erroneous rules because they are deterministic rules. Another is that it is hardand time-consuming to acquire rules because they should be manually acquired. In this paper, wepropose context-dependent lexical rules, which are lexical rules based on the statistics of a taggedcorpus, and an ambiguity-driven teaming method, which is the method of automatically acquiring theproposed rules from a tagged corpus. By using the proposed rules, the proposed tagger can partiallyannotate an unseen corpus with high accuracy because it is a kind of memorizing tagger that canannotate a training corpus with 100% accuracy. So, the proposed tagger is useful to improve theaccuracy of a stochastic tagger. And also, it is effectively used for detecting and correcting taggingerrors in a manually tagged corpus. Moreover, the experimental results show that the proposed methodis also effective for English part-of-speech tagging.

• 한국동물학회지
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• 제33권2호
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• pp.241-245
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• 1990

한국산 칼납자루 Acheilognathus limbata(Temminck et Schlegel)의 분류학적 재 검토를 위하여 일본산과 한국산의 표본에 대한 난의 형태와 발생과정 및 외부 형태 형질을 비교 분석하였다. 한국산 표본은 난의 형태가 장타원형이고 난할시 동물극에서 세포 분열이 이루어지지만 일본산 표본의 난형은 둥근 타원형이고 난황의 측면에서 세포 분열이 이루어지고 있어 발생학적인 차이가 현저하다. 한편 17개의 계수 계측 형질의 비교에서 두장에 대한 문장의 비가 일본산은 한국산에 비하여 작고, 양안 간격의 비에 있어서도 일본산이 한국산에 비하여 현저하게 다른 점등으로 한국산 표본은 일본산 Acheilognathus limbata와 동종이라기 보다 분류학적을 구분되는 별종일 가능성이 있어 이에 대하여 논의 하였다.

• 한국균학회지
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• 제46권2호
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• pp.105-113
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• 2018

본 연구에서는 2016년 5월에서 9월까지 제주 동부지역에서 채집된 317종의 버섯들 중 국내 미기록된 4종을 보고하고자 한다. 미기록종으로 추정되는 버섯의 정확한 동정을 위하여 채집된 자실체에서 분리한 DNA의 염기서열을 버섯의 유전자은행을 통하여 비교 분석한 결과 Agaricus flocculosipes, Amanita concentrica, Coprinopsis strossmayeri, Favolus acervatus로 동정되었으며 이들은 모두 국내 미기록종으로 확인되었다. 한편 현미경을 이용하여 버섯의 미세구조를 관찰한 결과는 모두 DNA 염기서열을 분석하여 동정한 버섯과 일치하였다.

• 비교문화연구
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• 제38권
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• pp.461-500
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• 2015

This study aims to investigate the effective method to improve the competence of the Vocabulary by the image and listening towards the ELF. In the first part, we observed the problems and point improvement on learning vocabulary based on learner survey. In the second part, we analyzed two remarkable studies: - consistent and adapt method, communicational context - method based on the lexical, morphological semantical, notional and thematic field Then we proposed effective methods that are applicable to the vocabulary's learning in the class : - learning vocabulary by combining the words - learning vocabulary based on the meaning field - learning vocabulary as concrete characters - learning vocabulary by the descriptive character - learning vocabulary with the type "who am I?" - learning vocabulary by listening For teachers, one of the difficulties to the conduct of vocabulary course is that learners take passive position. Specifically, it is the teachers who play an important role because it runs in the direction of the course. However, learners do not show the active attitude for vocabulary lessons despite the course to take to improve their vocabulary skills. Therefore, teachers must prepare course materials that can both improve the competence of the vocabulary of learners and cause their interest or desire on the current vocabulary. This is why teachers should exploit various materials depending on the skill level of the learner vocabulary.