• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.391-399
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• 2015

This study modeled the compressive strength and elastic modulus of hardened cement that had been treated with an expansive additive to reduce shrinkage, in order to determine the mechanical properties of the material. In hardened cement paste with an expansive additive, hydrates are generated as a result of the hydration between the cement and expansive additive. These hydrates then fill up the pores in the hardened cement. Consequently, a dense, compact structure is formed through the contact between the particles of the expansive additive and the cement, which leads to the manifestation of the strength and elastic modulus. Hence, in this study, the compressive strength and elastic modulus were modeled based on the concept of the mutual contact area of the particles, taking into consideration the extent of the cohesion between particles and the structure formation by the particles. The compressive strength of the material was modeled by considering the relationship between the porosity and the distributional probability of the weakest points, i.e., points that could lead to fracture, in the continuum. The approach used for modeling the elastic modulus considered the pore structure between the particles, which are responsible for transmitting the tensile force, along with the state of compaction of the hydration products, as described by the coefficient of the effective radius. The results of an experimental verification of the model showed that the values predicted by the model correlated closely with the experimental values.

• Applied Microscopy
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• v.46 no.1
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• pp.51-57
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• 2016

The histology and anatomy of the olfactory organ in Luciogobius guttatus was investigated using a light microscopy and scanning electron microscopy. The paired olfactory organs in the dorsal part of the snout are situated in between the upper lip and the eyes. They consist of two nostrils, one anterior and the other posterior openings, and a single olfactory cavity. The anterior nostril, an incurrent opening, forms a short tubular structure from the skin. The posterior nostril, an excurrent opening, forms a circular structure opened to the exterior. The distributional pattern of the sensory epithelium is a continuous type. The sensory epithelium with numerous-motile cilia is made up of receptor cells, supporting cells, basal cells, and mucous cells. In contrast, the non-sensory epithelium is comprised of stratified epithelial cells and two types of mucous cells, acidic and neutral cells. The cilia number of the receptor cell is in range of 3 to 4 units. Such results in L. guttatus may reflect its ecological habit and microhabitat in the tidal zone with a periodic tide.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.463-468
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• 2007

The abnormal sound of generator frame is analyzed by a acceleration signal. The spike-like time signal is major characteristics of impacting force. The distributional map of vibration level is one of visualization method. With map, noise source was easily detected. After de_assembly of generator, loose part of internal component is the source of impact force by mechanical movement of stator inherently. In contact condition of part with clearance, the level of impact signal is different at each revolution and impact signal did not happens periodically.

• Korean Journal of Environmental Biology
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• v.21 no.4
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• pp.428-438
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• 2003

Benthic marine algal community of Hakampo in the western coast of Korea was investigated qualitatively and quantitatively. Seasonal assessments of species composition, biomass, dominant species in biomass and vertical distributional pattern were carried out from spring to winter. A total of 121 species was identified; 6 blue-green, 18 green, 16 brown, 81 red algae. In three sites investigated, 96 species were collected at Bunjeomdo, 75 at Maoe, and 57 at Doranggol, respectively. Dermocarpa sp. and Acrochaetium microscopicum were collected for the first time in Korea through this investigation. Dominant species in specific proportions of biomass were Sargassum thunbergii, Gloiopeltis furcata, Corallina spp., Symphyocladia latiuscula and Monostroma nitidum. Seasonal fluctuations of mean biomass were 31.59-427.69 g dry wt$.$$\mu \textrm m^{-2}$ at Bunjeomdo and 20.98-473.48 g dry wt$.$$\mu \textrm m^{-2}$ at Maoe, respectively, which were comparatively high in the western coast of Korea. Vertical distribution in intertidal zones was Gloiopeltis furcata-Gloiopeltis furcata and Corallina spp.-Corallina spp. and Sargassum thunbergii.

• Journal of Plant Biology
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• v.33 no.4
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• pp.225-236
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• 1990

Intertidal algal communities of Muchangpo and Maryangri in western coast of Korea were investigated qualitatively and quantitatively. Seasonal assessments of species composition, biomass, dominant species in biomass and vertical distributional pattern were conducted from July 1986 to April 1988. Ninety-nine species of marine algae (13 Cyanophyta, 12 Chlorophyta, 24 Phaeophyta and 50 Rhodophyta) were observed, of which 90 (13 Cyanophyta, 11 Chlorophyta, 23 Phaeophyta and 43 Rhodophyta) were from Muchangpo and 83 (10 Cyanophyta, 11 Chlorophyta, 21 Phaeophyta and 41 Rhodophyta) were from Maryangri, respectively. Ordination by detrended correspondence analysis based on the floristic data from nine localities indicated that, on the whole, marine algal distribution in western coast of Korea might be divided into two regions, i.e. the north and the south, being separated at the Taean Peninsula, the mid-western coast. Seasonal fluctuations of mean biomass were 44.55-201.19g-dry wt/$m^2$ at Muchangpo and 19.59-134.76g-dry wt/$m^2$ at Maryangri. Important species determined by the specific proportion of biomass were Sargassum thunbergii, Pelvetia siliquosa and Corallina pilulifera at Muchangpo, and Sargassum thunbergii and Corallina pilulifera at Maryangri.

• Language and Information
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• v.13 no.1
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• pp.57-75
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• 2009

English floating quantifiers (FQ) are both limited and complex in the sense that they are introduced by a limited set of words, all, both, and each, and display free distributional possibilities. This paper provides a non-movement approach to the syntax of English floating quantifier constructions. The non-movement analysis we develop here is different from stranding movement analyses in that all the FQs are base-generated while the linkage with their antecedent refers to grammatical features such as SUBJ and PRD. The analysis avoids the postulation of abstract levels as well as empty elements in capturing the flexibility of English FQ constructions, making the grammar of English simpler.

• 한국생태학회:학술대회논문집
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• 2002.08a
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• pp.133-139
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• 2002

Regeneration process of the Korean beech (Fagus multinervis Nakai) forest was studied in relation to the distributional pattern and age structure. In this study, it was clarified that the Korean beech forest is regenerated in both way: seedlings(sexual reproduction) and sprouts(vegetative reproduction) formations. In the large gaps, seedling may be established, resulting in clusters of even-aged individuals. But in the small-sized gaps, there may filed by the extention of surrounding trees and/or by the young trunks, which have sprouted from the base of stumps. As most gaps in the F. multinervis forest were derived from falling of a single stem, regeneration by sprouts seems to be more common than that by the seedlings.

• Applied Microscopy
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• v.25 no.1
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• pp.15-29
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• 1995

Legumin was purified from the endosperm cells of the ginseng seed and analyzed its characteristics. Distributional patterns of the legumin in the endosperm cells were identified using the immunocytochemical method. Legumin was glycoprotein composed of two subunits, molecular weights about 33,000 and 25,000 respectively. The molecular shape of purified legumin stained negatively seems to have hexagonal structure about 10 nm in size. It was localized at the rER, dictyosomes, and in the vacuoles at the early developing stage. Legumin was glycosylated in the dictyosomes and transported from the dictyosomes to the vacuoles. Legumin was accumulated into the central vacuole via the dictyosomes while the endosperm cells were developing. The armorphous proteins containing legumin were scattered randomly within the central vacuoles, which were aggregated together and became gradually spherical shape. Legumin was distributed within the globular protein bodies in the endosperm cells of matured seed. However legumin was not found in the globoids located in the protein bodies.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.267-273
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• 2002

Regeneration process of the Korean beech (Fagus multinervis Nakai) forest was studied in relation to the distributional pattern and age structure. In this study, it was clarified that the Korean beech forest is regenerated in both way: seedlings(sexual reproduction) and sprouts(vegetative reproduction) formations. In the large gaps, seedling may be established, resulting in clusters of even-aged individuals. But in the small-sized gaps, there may filled by the extention of surrounding trees and/or by the young trunks, which have sprouted from the base of stumps. As most gaps in the F. multinervis forest were derived from falling of a single stem, regeneration by sprouts seems to be more common than that by the seedlings.

• Ocean and Polar Research
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• v.28 no.1
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• pp.13-23
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• 2006

This study was conducted to investigate the community structure and distributional pattern of meiobenthos on the sediment of the mangrove forest and seagrass bed in the Chuuk lagoon. The samples were collected by an acryl corer at 14 stations. Nematodes were the most abundant meiobenthos, followed by ciliophorans and polychaetes; these taxa comprised more than 70% of the total abundance at all stations. The meiofuuna sampled in seagrass bed were more diverse than those of mangrove substrates. Total densities were higher in mangrove stations than other sites, averaging 1,671 to $2,967inds/10cm^2$. Densities in seagrass area ranged between 605 and $1,053inds/10cm^2$. Biomasses, however, were higher in seagrass bed $(975-2,167{\mu}g\;free\;dry\;weight/10cm^2)$ than in mangrove area $(1,064-1,180{\mu}g\;free\;dry\;weight/10cm^2)$. Ordination chart by MDS of major meiofaunal density in each station showed difference between mangrove area and seagrass area in terms of habitat of meiobenthos.