• Journal of Pharmaceutical Investigation
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• v.21 no.4
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• pp.201-213
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• 1991

There are many drugs reproted to show unusual pharmacokinetic behavior by producing a significant secondary peak in the plasma concentration-time curve after oral administration. The drugs are ranitidine, cimetidine, acetaminophen, aspirin, furosemide, bumetanide, piretanide, veralipride, sobrerol, penicillamine and doxycycline etc. Enterohepatic circulation-, two absorption site-, biphasic gastric emptying-, tissue deposition- and multi-fraction absorption theories have been suggested for the mechanisms of this phenomenon. Here, the theories were reviewed and critisized for their validity as a possible mechanism of the multiple peak phenomenon.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.85-88
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• 2002

In order to visually analyze the flow characteristics, gas was injected into the liquid bath through nozzle installed at the center of bottom of the bath. When gas was injected into the liquid bath, several flow patterns were observed bubble-liquid plumb, the spout flow that occurred at the free surface, liquid circulation flow by bubble's behavior, etc. Various bubbles, from small bubbles to Taylor bubbles, consisted of the bubble-liquid plumb. In the pure liquid region, the large and small several vortices were formed and irregularly circulated. These irregular repetition and circulation play a important role of mixing in the bath. The vortices were developed in the upper and the side wall regions and the movement of flow in the low region was very small. It is known as 'dead zone'.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.522-529
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• 2014

Circulating fluidized bed system consists of SEWGS reactor - lower loop seal - regeneration reactor - riser - cyclone - upper loop seal has been used for solid circulation between the SEWGS reactor and the regeneration reactor in a SEWGS system for pre-combustion $CO_2$ capture. A vertical type lower loop seal has been used in current system but this lower loop seal requires high gas flow rate through the lower loop seal for fluidization and smooth solid circulation, and consequently, causes slugging behavior sometimes. To overcome these disadvantages, inclined type lower loop seal was proposed by this study. Solid circulation characteristics with change of lower loop seal geometry were measured and compared in a bubbling - bubbling - riser type circulating fluidized bed using $CO_2$ absorbent (P-78) as bed material at ambient temperature and pressure. We could conclude that the inclined lower loop seal is better than the vertical type lower loop seal from the viewpoints of minimum flow rate requirement for stable solid circulation and solid height change during solid circulation.

• Tribology and Lubricants
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• v.15 no.3
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• pp.278-286
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• 1999

To predict the behavior of the intravascular micro active endoscope in the real human vascular system, a human mock circulation system was developed. The intravascular micro active endoscope which consists of micro active bending catheter and micro drug infusion catheter was driven in the velocity, Re number and temperature controlled flow. The three SMA (Shape Memory Alloy) zigzag type spring in the micro active bending catheter was heated by the electric current generated by PWM controller, and the shape memory effect made the actuator bend to any direction. The micro drug infusion catheter was driven through the inner hole of the micro active bending catheter. A mock circulation system is shaped from Ascending Arota to Femoral artery according to a human data (the data contains many vascular sizes and hydrographs of many control points). We developed a vascular model with glass and silicone tubes, and set the flow system with circulation parts, flow settling parts, and lots of valves. The heater and heat-controller was added to the How system to centre! the temperature of the How at 36.5$^{\circ}C$. The result showed that the developed intravascular micro active endoscope could be induced to any point in the vascular model.

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.149-155
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• 2011

This paper presents simulations of advance evacuation analysis using a cellular automata model for passenger behavior in an emergency of passenger ship. The proposed cellular automata model divides the space in a uniform grid called "cell." Each passenger is located in a cell and moves to another cell according to a set of local rules assumed to be associated with the individual and crowd behaviors of the passengers. To verify the usefulness of the proposed cellular automata model, 11 tests, all of which are specified in International Maritime Organization Maritime Safety Committee/ Circulation 1238 (IMO MSC/Circ. 1238), were implemented, and it was confirmed that all the requirements of these tests had been met.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1085-1089
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• 2001

Metabolites, such as isopropyl alcohol (IPA) produced by rumen fermentation, were intravenously infused into a jugular vein of goats during feeding to explore the mechanism and roles of IPA in ruminating behavior (number of boli and ruminating time). Three female goats were confined in metabolism cages with a stanchion, The ruminating behavior measured by the number of ruminations, ruminating time, number of remastications, and remasticating time decreased (p<0,05) with intravenous IPA infusion. The IPA concentrations and VFA concentrations increased in the blood circulation. Our data suggest that sensitive receptors of rumination to IPA are more likely to be in an area such as the brain stem where they can respond to blood metabolite levels.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.570-575
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• 2005

An efficiency of a refrigeration cycle and a reliability of a compressor can be reduced if a refrigerant including excessive lubricating oil is exhausted from a rotary compressor. Thus, the oil behavior inside the compressor should be analyzed to improve the efficiency. A tested rotary compressor has been manufactured with visualization windows at upper parts in this study to investigate the oil behavior using developed visualization techniques. Discharge pipe with level gage has been visualized to investigate discharged oil amount. The oil behaviors inside the compressor and discharging pipe at various operating conditions have been analyzed. The results of the visualization for the discharging pipe have been compared with those of the upper part to confirm the accuracy.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3320-3325
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• 2023

The scaled water-cooled Reactor Cavity Cooling System (RCCS) experimental facility reproduces a passive safety feature to be implemented in Generation IV nuclear reactors. It keeps the reactor cavity and other internal structures in operational conditions by removing heat leakage from the reactor pressure vessel. The present work uses Flownex one-dimensional thermal-fluid code to model the facility and predict the experimental thermal-hydraulic behavior. Two representative steady-state cases defined by the bulk volumetric flow rate are simulated (Re = 2,409 and Re = 11,524). Results of the cavity outlet temperature, risers' temperature profile, and volumetric flow split in the cooling panel are also compared with the experimental data and RELAP system code simulations. The comparisons are in reasonable agreement with the previous studies, demonstrating the ability of Flownex to simulate the RCCS behavior. It is found that the low Re case of 2,409, temperature and flow split are evenly distributed across the risers. On the contrary, there's an asymmetry trend in both temperature and flow split distributions for the high Re case of 11,524.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1768-1772
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• 2008

The authors previously presented that the experimental technique using fine bubbles generated by electrolysis simulated fire behavior in a tunnel. We improve this experimental setup to enable this to be considered tunnel-ventilation by circulation of salt water. In this paper we introduce the new experimental setup and the visualization of fine hydrogen bubbles simulated smoke in a ventilated tunnel by using a laser sheet are presented.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.236-243
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• 2005

The pre-examination closely beforehand relation between the articles on exhibition and visitors, the visitors and exhibition space, the exhibition space and the articles on exhibition, and the acceptance of various requirements are the matters you should consider in the initial stage when planning the establishment of a museum. Especially, the clear guideline for the layout of exhibition to meet the intention of spectators considered based on the seeing behavior in the exhibition hall (i.e. they see the articles on exhibition in order passively under instructions of the museum or select them by themselves positively etc.), and the moving line of appreciation and the exhibition type seems to be not yet prepared sufficiently. This study can be defined as the study of fundamental background for the architectural guideline for the characteristics of visitor's behavior, the selected moving line in the exhibition hall, the layout against the forced moving line and the type of exhibition space. As a part of this study, we carried out the research and the study for how the movement of visitors and the characteristics of seeing behaviors according to the type of the moving line are shown, based on the type of moving line for seeing suggested by David Dean.