• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.217-218
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• 2011

The advantages of blast-furnace slag concrete may include lower hydration heating velocity, restraint on concrete temperature increase, long-age strength improvement due to latent hydraulic reaction, improved water tightness, and repulsion to chemical erosion. These advantages contribute to the high quality of the blast-furnace slag concrete. However, the blast-furnace slag concrete has its limitations as well. These disadvantages may include retarded setting and elongated retention of mold due to the weak strength of early-age. Nevertheless, much research is currently under way to improve the aforementioned issues. To improve activity of blast furnace slag powder, alkaline irritants has been used. In this study, we analyze effect on activity fineness and rate of substitution of Alkali Activator toward activity.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.83.2-83.2
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• 2017

We report observations of light bridge (LB) jets taken with the New Solar Telescope. Jets as dark, fine threads occurred lined along both edges of a LB of a sunspot, which is a bright and elongated structure that divides a sunspot's umbra into two or more parts. This LB jets are observed for about three hours with $H{\alpha}$ filtergraph at ${\pm}0.4{\AA}$, ${\pm}0.8{\AA}$ from the line center, TiO filtergraph, and near infra-red imaging spectropolarimeter (NIRIS). High resolution $H{\alpha}$ data revealed that subsequent ejection of LB jets were associated with subsequent brightening along the edge of the LB. Also, this subsequent brightening was spatially correlated with both photospheric flow and magnetic field change detected from the TiO and NIRIS data, respectively. Preliminary results of LB jet observation and discussions on its formation mechanism will be presented.

• 한국전산유체공학회:학술대회논문집
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• 2006.10a
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• pp.66-69
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• 2006

In the present study, we propose a virtual boundary method for simulation of massive inextensible flexible strings immersed in viscous fluid flow. The fluid motion is governed by the Navier-Stokes equations and a momentum forcing is added in order to bring the fluid to move at the same velocity with the immersed surface. A massive inextensible flexible string model is described by another set of equations with an additional momentum forcing which is a result of the fluid viscosity and the pressure difference across the string. The momentum forcing is calculated by a feedback loop. Simulations of several numerical examples are carried out, inlcuding a hanging string which starts moving under gravity without ambient fluid, a string swimming within a uniform flow and a uniform flow over two side-by side strings. The numerical results agree well with the theoretical analysis and previous experimental observations. Preliminary results of a swimming elongated fishlike body will also be presented.

• Toxicological Research
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• v.11 no.2
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• pp.169-173
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• 1995

The effects of tumor necrosis factor alpha $(TNF-{\alpha})$ on growth and tubular formation of bovine aortic endothelial cells were examined using an in vitro angiogenesis model system. The growth of endothelial cells was enhanced in a dose-dependent manner when the cells were cultured with $TNF-{\alpha}$ for 3 days, but $TNF-{\alpha}$, at the concentration of 1 nM or higher, produced a growth inhibition of endothelial cells when the cells were cultured for 8 days. The endothelial cells incubated with $TNF-{\alpha}$ for 48-h exhibited a typical morphologic change. Then, they showed a fibroblastoid organization of overlapping, elongated, and spindle-shaped cells. $TNF-{\alpha}$, at the concentration of O. 1 nM or higher, inhibited the tubular formation of vascular endothelial cells in an in vitro anglogenesis model using a 3-dimensional culture system.

• Computers and Concrete
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• v.2 no.2
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• pp.147-164
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• 2005

This paper summarizes an experimental study on the seismic behavior of lower stories of a mid-rise reinforced concrete frame building. Two reinforced concrete frames with two stories and one span were tested and each frame represents lower two stories of an 11-story RC frame building. Both frames were designed in accordance with Japanese design guidelines and were identical except in the variation of axial force. The tests demonstrated that the overall load-displacement relations of the two frames were nearly the same and the first-story column shear was closely related to the column axial load. The columns and beams elongated during both of the tests, with the second-floor beam elongation exceeding 1.5% of the beam clear span length. The frame with higher axial loads developed more cracks that the frame under moderate axial load.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.115-122
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• 2005

This study analyzed the characteristics of four kinds of bridge rubber pads and suggested how to determine the stiffness the pads. The stiffness of rubber pads can be estimated by a direct static test. In the procedure to estimate the stiffness of a pad, the dead load(preload) of a bridge and live load of a vehicle are considered. The polyurethane rubber pads have larger hardness than natural and chloroprene rubber pads and thus carry larger load bearing capacity. In addition, they showed higher stiffness with the same shape factor than the others and thus are more avaliable as for bridge bearings. Although natural and chloroprene rubber pads are elongated to large deformation in horizontal direction due to vertical loads, polyurethane rubber pads almost do not generate horizontal deformation due to vertical loads regardless to the thickness and hardness of the pads. Therefore, they do not need reinforced plate to restrict horizontal deformation.

• Journal of Plant Biology
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• v.38 no.3
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• pp.281-288
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• 1995

The progressive differentiation of interfascicular cambium from residual meristem in the first internode of Ginkgo biloba seedlings was elucidated by light and electron microscopy. The cells of residual meristem were small and homogeneous and heterogeneous in their arrangement but those of the adjacent cortex and pith were large and homogeneous. Some interprocambial residual meristem progressively became elongated and vacuolated during the process of the differentiation. In tangential section, residual meristem composed of long and short cells. The eventual interfascicular cambium had long fusiform initials and short ray initials. Storage materials in the cells progressively disappeared from the interprocambial residual meristem and were absent in early interfascicular cambium. Both the radial and tangential walls of cells of the interprocambial residual meristem were almost the same, but the radial wall became progressively thicker than the tangential wall during differentiation of interfascicular cambium. From these results, it is clear that interfascicular cambium is gradually differentiated from residual meristem.

• Journal of Plant Biology
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• v.34 no.4
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• pp.311-316
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• 1991

The origin of cambial initials from procambium was studied in the seedling root of Acer saccharinum. In transverse view, the first periclinal divisions of procambial cells occurred just outside of each early metaxylem and resulted in meristematic strips. As root development progressed, the division activities appeared subsequently outside of each late metaxylem and then in pericycle cells opposite the four protoxylem poles. Eventually, such meristematic strips were connected completely each other. Thus, a nearly rectangular shaped meristematic layer in outline was formed outside the xylem in a whole root transectioned. In tangential section, early procambium showed a homogeneous structure consisted of uniform short cells with transverse end walls. However, some of the procambial cells did elongate, whereas others divided transversely. The former become more elongate, tapered, and vacuolated. Finally, they differentiated into fusiform initials. Short cells consisting axial strands divided continuousely in transverse plane and became ray initials, while some short cells elongated and transformed into long cells. The early ontogeny of vascular cambium in Acer saccharinum root was interpreted to be established by a gradual process.

• Journal of Plant Biology
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• v.34 no.4
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• pp.274-281
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• 1991

The relationship between elongation of hypocotyl and its vascular transition was studied with seedling of Glycine max. the hypocotyl elongation proceeded acropetally from the base of hypocotyl toward the cotyledonary node. The vascular transition did not occur in the basal region of the hypocotyl, which did not nearly elongate, with exarch radial vascular bundles. However, the vascular transition was almost completed at the middle part of the hypocoty, more or less elongated, with endarch collateral vascular bundles. Such bundles also appeared in the uppermost region of the hypocotyl, in which the elongation was the most striking. These results suggested that the vascular transition was related to the hypocotyl elongation and that the transition of primary vascular system in Glycine max seedling was established by rather rapid process. Our observations of the serial sections from root to hypocotyl revealed that the vascular system through the root-hypocotyl-cotyledon was a unit, to which one of the epicotyl that did not participate in transition was superimposed.

• The Korean Journal of Cytopathology
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• v.6 no.1
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• pp.80-83
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• 1995

Malignant fibrous histiocytoma is the most common soft tissue sarcoma of late adult life, but it is rare in the pleura. We recently experienced a case of cytology of malignant fibrous histiocytoma in plural fluid. The smear revealed histiocytic malignant cells, spindle malignant cells and inflammatory cells. The histiocytic cells showed abundant, pale cytoplasm and ovoid, irregular eccentrically-placed nuclei. The spindle cells showed elongated nuclei. Intercellular collagen was also present.