• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.663-666
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• 2005

The geometry stage, which performs the transformation and lighting operations of vertices, became the critical part in 3D graphics pipeline. In this paper, we have planned and designed the Geometry Processor for the better and more efficient way to process the real-time 3D using the floating point unit. We also designed a verification system for Geometry engine. It is implemented with Xilinx-Virtex2 and Visual C++.NET. In the Synopsis, we confirmed 100 MHz performance and 137107 cell area of Geometry Engine.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.253-258
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• 2001

Control of drag force on a circular cylinder using a detached splitter plate is numerically studied for laminar flow. A splitter plate with the same length as the cylinder diameter(d) is placed horizontally in the wake region. Its position is described by the gap ratio(G/d), where G represents the gap between the cylinder base point and the leading edge of the plate. The drag varies with the gap ratio; it has the minimum value at a certain gap ratio for each Reynolds number. The drag sharply increases past the optimum gap ratio; this seems to be related to the sudden change in the bubble size in the wake region. This trend is consistent with the experimental observation currently available in case of turbulent flow. It is also found that the net drag coefficient significantly depends on the variation of base suction coefficient.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.82-85
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• 2004

This paper proposes the development of delay compensator to minimize performance degradation caused by time delays in network-based real-time control systems. The delay compensator uses the time-stamp method as a direct delay measuring method to measure time delays generated between network nodes. The delay compensator predicts the network time delays of next period in the views point of time delays and minimizes performance degradation from network through considering predicted time delays. Control output considering network time delays is generated by the defuzzification of probable time delays of next period. The time delays considered in the delay compensator are modeled by using a timed Petri net model. The proposed delay prediction mechanism for the delay compensator is evaluated through some simulation tests by measuring deviation of the predicted delays from simulated delays.

• Journal of Plant Biology
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• v.15 no.2
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• pp.7-19
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• 1972

The studies of density effect or the effect of population density on plant growth have been done on basis of dry matter production with Raphanus acanthiformis var. simoodaeguen, Brassica campestris var. Pekinensis f. namsounsokoombecheu, Oryza sativa f. kimmajae and O. sativa f. mangyeng grown in the various spacing. 1. In the early period of plant growth in dry weight was not different each other among varying densities, but as time advanced the plant grown vast space grew sufficiently compared with those of narrow one. 2. Iogarithmic relation between the growth of plant (W) and the density (P), log W-log P in the material plants, were approximated by two straight lines, one was horizontal line and another inclined: the former showed non-competition density and the latter competition density addition to these the point interlinking both lines were implied of the optimum density per unit land area at certain growth period. 3. The values of relatvie growth rate (RGR) and net assimilation rate (NAR) were decreased as increase in the density, while those of leaf area ratio (LAR) were rather increased in the same condition, with minor exception. From these results and relation between the productive structure and due to lack of the recieved light intensity owing to the mutal shading among the plants.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.13 no.4
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• pp.237-245
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• 2009

A numerical solution is provided for a jet produced by a flow emerging from a slit at the bottom corner of a quarter plane. The flow is characterized by the Froude number F, based on the net volume flux and the width of the slit. We perform the free-surface flow for various values of F and another parameter corresponding to the position of the vertical wall. A jet with back-flow near the edge of the vertical wall is obtained, and the limiting case is a jet with a stagnation point.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.88-93
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• 1994

The mechanisms controlling the intensity and duration of synaptic transmission are numerous. Once an action potential reaches a nerve terminal, the stored neurotransmitters are released in a quantum fashion into the synaptic cleft. At that point neurotransmitters can act on post-synaptic receptors to elicit an action on the post-synaptic cell or net at so-called auto-receptors that are located on the presynaptic side and which often regulate the further release of the neutotransmitter. Whereas the action of the neurotransmitter receptors is regulated by desensitization phenomenon, the major mechanism by which the intensity and duration of neurotransmitter action is presumably regulated by either its degradation or its removal from the synaptic cleft. In the central nervous system, specialized proteins located in fe plasma membrane of presynaptic terminals function to rapidly remove neurotransmitters from the synaptic cleft in a sodium chloride-dependent fashion. These proteins have been referred to as uptake sites or neurotransmitter transporters. Once taken up by the plasma membrane transporters, neurotransmitters are repackaged into secretory vesicles by distinct transporters which depend on a proton gradient.

• IE interfaces
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• v.17 no.spc
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• pp.62-68
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• 2004

HAPS (High Altitude Platform Station) which is defined as a station located on an object at an altitude of 20 to 50 km and at a specified, nominal, fixed point relative to the earth is a promising technology capable of providing broadband multimedia services. In this study, economical aspects of HAPS service are analyzed by estimating the revenue and costs incurred by the service. To evaluate the profitability of HAPS service, the number of subscribers is estimated and then the net present value (NPV), payback period, and the rate of return on investment (ROI) are calculated under various scenarios.

• Journal of Computing Science and Engineering
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• v.7 no.3
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• pp.198-203
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• 2013

In this paper, we focus on a novel Internet architecture, based on the urbanization of virtual machines. In this approach, virtual networks are built linking specific virtual elements (router, switch, firewall, box, access point, etc.). A virtual network represents a network with an independent protocol stack that shares resources from the underlying network infrastructure. Virtualization divides a real computational environment into virtual computational environments that are isolated from each other, and interact with the upper computational layer, as would be expected from a real, non-virtualized environment. Metamorphic networks enhance several concepts related to future networks, and mainly the urbanization of virtual machines. We present this new paradigm, and the methodology, based on the worldwide metamorphic network platform "M-Net". The metamorphic approach could solve many complex problems, especially related to Cloud computing services.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.520-524
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• 2008

This research verifies the phenomenon of which the Momentum and Reversal effect of stock price would depend on the subject of investment in the point of view of the Behavior Finance hypothesis. For the experiment, this paper uses the KOSPI200 daily data and Net Investment Flow from Jan. 1999 to Dec. 2006. And we analyze the marginal profit and loss with foreigners, individual investors, and institutions. We verify the response of the subjects of investment based on the CAR for 3 days after more than 3 percent rising or drop. We also verify the response with respect to the ascending and descending trend based on the profit trend and subjects' behaviors a week before the drop.

• Satellite Communications and Space Industry
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• v.13 no.1 s.28
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• pp.118-124
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• 2006

HAPS(High Altitude Platform Station) which is defined as a station located on an object at an altitude of 20 to 50 km and at a specified, nominal, fixed point relative to the earth is promising technology capable of providing broadband multimedia services. In this study, economical aspects of HAPS service are analyzed by estimating the revenue and costs incurred by the service. To evaluate the profitability of HAPS service, the number of subscribers is estimated and then the net present value (NPV), payback period, and the rate of return on investment (ROI) are calculated under various scenarios