• Journal of Plant Biology
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• v.28 no.3
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• pp.199-206
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• 1985

Antithamnion miharae (Tokida) Itono was investigated in field and laboratory culture. The plant grows in lower littoral zone through out the year in Korea. The gland cells occur scarcely or commonly according to the populations, but the terminal hairs in the female plants are not observed. The structure of vegetative thallus and the reproductive organs in culture are similar to those of field materials, except for the number of gonimoblasts, which become five to six in contrast to one to three of the field. A typical Polysiphonia-type life history is repeated in culture. This species which produces tetrahedral tetrasporangia is markedly distinguished from Antithamnion glandulifera sensu Kylin (=Antithamnionella glandulifera (Kylin) Wollaston) which produces cruciate tetrasporangia, while the plants reported by Dawson (1962) and Wollaston (1971) as A. glandulifera seem to be conspecific with A. miharae by the fact that they have the tetrahedral tetrasporangia in stead of cruciate ones.

• ALGAE
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• v.22 no.3
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• pp.159-165
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• 2007

Morphological and anatomical characters of Amphiroa rigida Lamouroux were investigated with field materials and taxonomic accounts are given to the species. The species grows in the subtidal zone of Cheju island, and is characterized by semiendophytic habit in Hydrolithon onkodes. The species is well defined by about 1 cm height, loosely tufted thallus with irregular branches, two-tiered geniculum with equal length, geniculum tier connecting by oblique end walls, and conceptacles buried in cortices of intergeniculum. Korean isolates have etrasporangial, male and female conceptacles. The structure and developmental patterns of conceptacles are very similar to those shown in previous studies.

• Korean Journal of Pharmacognosy
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• v.25 no.2
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• pp.117-120
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• 1994

As part of search for new biologically active substances from marine organism, we have isolated a glyecrol glycoside from the marine red alga Gracilaria verrucosa. The structure of the glycerol glycoside was elucidated as 2-O-${\alpha}-_D$-galactopyranosylglycerol[floridoside(4)] on the basis of spectroscopic and physicochemical evidences.

• Journal of the Korean Institute of Telematics and Electronics
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• v.9 no.5
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• pp.34-42
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• 1972

Current noise is an important indication of quality in deposited carbon film resistors. Imperfections in the resistive film create high current densities and consequently high current noise. The magnitude of current noise is depend upon many inherent properties of the resistor such as resistive material and others such as processing, fabrication and packing of resistive elements, etc. Performance tests have definitely established a correlation between current noise and electrical performance of carbon film resistors. To interprete the normal distribution of the current noise index for representative groups of resistors would serve as a powerful tool in judging the Quality control and product uniformity by the manufacturer.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.301-307
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• 1997

In this study, a new modified independent modal space control (IMSC), which relaxes the fundamental hardware limitation of IMSC, is suggested to handle vibration control problems using a virtual passive controller. This method has adapted a new stable switching algorithm between controlled modes and a virtual vibration absorber as a virtual passive controller in the independent modal space. It has been found that the new modified IMSC suggested in this paper, which can reduce the number of actuators, is shown to be simple and efficient in a realistic example of vibration control of a cantilever beam.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.77-78
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• 2008

최근 이산화탄소 흡수원으로 해조류의 배양과 이산화탄소 고정에 대한 영향 분석연구가 세계적으로 활발하게 진행되고 있다. 또한, 해조류에서 바이오에너지를 얻기 위한 연구와 해조류의 구성성분인 섬유, 당 및 지질을 이용하기 위한 연구도 다양하게 진행되고 있다. 해조류 섬유는 주로 종이 및 바이오복합재료 제조에 사용되며 추출물은 식품 등에 사용될 수 있다. 특히, 해조류 섬유는 셀룰로오스 섬유와 유사한 특성을 가지기 때문에 바이오복합재료의 천연섬유 보강재로서 사용이 가능하다. 바이오복합재료는 천연섬유를 보강재로 사용한 에너지절약과 친환경 특성을 가진 고분자복합재료로서 현재 자동차 및 건축물의 내장재로 사용되고 있는 유리섬유 보강 고분자복합재료를 대체할 수 있는 신소재이다. 본 논문에서는 해조류 기반 친환경 에너지소재의 세계적 연구동향 및 해조류 섬유를 이용한 신소재 개발연구로서 홍조류 섬유 보강 바이오복합재료에 대한 연구결과를 소개하고자 한다.

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.2
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• pp.45-57
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• 2007

Properties of newly developed paper from Red Algae Pulp (RAP) were examined. The paper samples were prepared according tomixing RAP fiber with wood fibers, HwBKP and SwBKP, to form a paper with $60\;g/m^2$ in weight. It was prepared in three to four different levels of refining degree and pressure so that it can reveal different bulk level in order to clearly compare the opacity at equivalent bulk for each furnish compositions. printability of RAP fiber revealed superior effect on print through repression and initial ink absorption. Those properties are expected to improve further if printability improvement effect due to smoothness improvement is added.

• Journal of Plant Biology
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• v.12 no.4
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• pp.1-8
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• 1969

According to the mode of development of antheridia and antheridial mother cells, the antheridium formation of Rhodymeniales is divided into two types. I. Separate Type; Antheridial mother cells are separate one another. Antheridia and the mother cell are surrounded by the common wall. The superficial gelatinous wall covering antheridial sori disappears during the antheridium formation. Spermatia are comparatively large. Halosaccion saccatum, H. firmum, Rhodymenia palmata and Rh. marginicrassa. II. Seriate Type; Antheridial mother cells, originated from the same epidermal cell, are seriate one another with a pit-connection. Antheridia and the mother cell do not have the common wall. The superficial gelatinous wall remains during the antheridium formation. Spermatia are comparatively small. Rhodymenia intricata, Rh. pertusa, Chrysymenia wrightii, Lomentaria hakodatensis, L. catenata, Binghamia californica and Champia parvula.

• Journal of Plant Biology
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• v.27 no.4
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• pp.233-239
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• 1984

Reproductives structures of Pachymeniopsis elliptica (Holmes) Yamade (Rhodophyta, Grateloupiaceae) are investigated. In female gametophyte the carpogonial branch and auxiliary cell are produced in separate accessory branch system, the primary ampullar filament originated from mid-cortical layer. After fertilization, auxiliary cell joined with connecting filament becomes a fusion cell by fusing with several neighboring ampullar cells. The fusion cell produces a gonimoblast initial. It divides into gonimoblast cells, which later convert to carposporangia. In male gametophyte superficial cortical cells of vegetative filament produce two spermatangial mother cells which cut off up to three spermatangia respectively. Tetrasporangial initials are formed from the 6th to 12th cells of the cortical layer in tetrasporophyte, and divided cruciately to form tetrasporangium. Some of the sporangia are, however, divided zonately.

• Journal of Plant Biology
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• v.26 no.3
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• pp.141-150
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• 1983

Antithamnion sparsum Tokida isolated from the southern and western coasts of Korea was investigated in culture, comparing the morphological character with A. defectum Kylin from the Pacific North America. A. sparsum basically showed a Polysiphonia-type life history. However, it sometimes exhibited a monoecious reproducton and the carpospores released from the cystocarp by self-fertilization unexpectedly developed into the plants bearing spermatangia alone. These male plants were not functional up to 60 days culture. The results of intraspecific crosses between populations of A. sparsum were positive and the hybrid carpospores gave rise to normal tetrasporophytes. On the other hand, theinterspecific crosses between A. sparsum and A. defectum were successful partly, evidenced by the gonimoblast development and the release of carpospores in case of A. sparsum (male)$\times$A. defectum (female), but not in case of A. sparsum (female)$\times$A. defectum (male). Thus, the both species were still under the speciation.