• Journal of the Korean Ceramic Society
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• v.33 no.10
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• pp.1079-1088
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• 1996

Discontinuous ${\gamma}$-LiAlO2 fibers for fiber-reinforcing MCFC matrixes have been produced by the sol-gel process using the centrifugal spinning apparatus of the Rotary type. Gel fibers could be obtained through spinning of stable LiAlO2 complex polymetric sols under the optimum spinning conditions (hollow-disc rotating velocity 9000 rpm sol feeding rate of 4ml/min flowing N2 temperature of 4$0^{\circ}C$ and flowing N2 pressure of 4 bar). It was found that defect free and densified ${\gamma}$-LiAlO2 fibers with the relative density of 98% and the mean diameter of 4.7${\mu}{\textrm}{m}$ were prepared when the spinned fibers were heat-treated to 100$0^{\circ}C$ on the specified heating schedule. in particular the mean diameter and length of fibers could be controlled by the pressure of flowing N2 and the chopping-sieving method respectively.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.286-288
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• 1990

This paper reports the characteristics of sparkover discharge in flowing air ranging from 0[m/s] to 30 [m/s] under the needle-needle gap. Flowing air duct of this investigation is circular tube. The important results obtained form this study are as follows. 1. the ratio of sparkover voltage to the Reynolds number decreases with increasing the Reynolds number. 2. The duration time of sparkover(t) decreases with increasing the Reynolds number. 3. the empirical equation obtained form this experiment is [ %]${\frac{Vs}{Re}}$ = A + $B{\varepsilon}^{C.Re}$ where A = 10.2 b = 125 c = -4.66 ${\times}$ $10^{-5}$

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.327-329
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• 2006

In this paper, PLC program for flowing type steam boiler control is presented. The function of the implementation are flowing type steam boiler, PLC control, interpretation of PLC command, and temperature scheme. The flowing type steam boiler approach is based on master-slave control concept. To show validity of the developed PLC program, severial experiments are illustrated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.89-92
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• 2006

To investigate the properties of high flowing and high strength concrete with crushed sand and fly ash for CFT structure, many batches were performed by a trial-error method. In the experiment W/B was set up three levels as 0.25, 0.30 and 0.35. Also the variables of the experiment were a substitution ratio of fly ash, a blend ratio of crushed sand and the ages of specimens(3, 7, 28 days). The results of this study are summarized as the follows; 1) The effect a substitution ratio of fly ash on the compressive strength was not consistent with age. For twenty-eight day compressive strength, the best result was come out when cement was substituted by 10% of fly ash. 2) The decrease of the water binder ratio, the increase of compressive strength and elastic modulus. Also the relationship is very similar to the case of a normal concrete

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1798-1800
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• 1997

Object of this paper is to find the best shape of cylinder, flowing velocity of gas and state of pole with the cylinder wire magnet type. Also it is to analysis phenomena arising in the cylinder. So that general program FLUX2D has used for magnetic and electric field analysis at the cylinder wire magnet type. General program PHOENICS has used for cold or hot gases flowing analysis at the cylinder wire type with magnet.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.123-128
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• 2014

In this study, we have investigated the flow rate effects of Ag nanoparticle (NP) suspensions on the progress of the cell cycle by using a microfluidic image cytometry (${\mu}FIC$)-based approach. Compared with the conventional "static" exposure conditions, enhancements in G2 phase arrest were observed for the cells under continuously flowing "dynamic" exposure conditions. The "dynamic" exposure conditions, which mimic in vivo systems, induced an enhanced cytotoxicity by accelerating G2 phase arrest and subsequent apoptosis processes. Moreover, we have also shown that the increases in delivered NP dose due to the continuous supply of Ag NPs contributed dominantly to the enhanced cytotoxicity observed under the "dynamic" exposure conditions, while the shear stress caused by these slowly flowing fluids (i.e., flow rates of 6 and $30{\mu}L/h$) had only a minor influence on the observed enhancement in cytotoxicity.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1615-1618
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• 1994

This paper studied the streaming electrification of the U.H.V. transformer with the spinning cylinder system, and compared and analyzed it with the conventional forced flowing system which uses a pump or gas for oil flowing. Also, accumulated surface voltage in its electrified material was measured with the electrostatic voltmeter, and the effect of insulation oil aging was measured. As results, in spinning cylinder system, characteristics of the streaming electrification to its rotational speed and oil temperature are same tendency as those of tile forced flowing system and it showed the spinning cylinder system is useful to study the streaming electrification. And, aging of insulation oil increases the electricity of streaming electrification at initial stage of aging.

• 레미콘
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• no.7 s.68
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• pp.9-16
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• 2001

Execution of exposed concrete has some problems such as segregation, surface honey comb and insufficient surface flossing due to unsuitable mix proportion and unfavorable construction in our field. Therefore, in this paper, field application of exposed concrete at training center building of Chongju university in Daecheon are carried out based on the mixing data obtained from laboratory test. Base concrete are made in accordance with mixing data. Segregation reducing type superplasticizer developed are applied in order to flow the vase concrete with out segregation of materials. According to test results, air content shows to be reduced after flowing. Compressive strength of flowing concrete is higher than that of base concrete about 7%. Surface glossing is reducing as the age goes on. It is improved about 10% compared to that of vase concrete.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.7
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• pp.567-573
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• 2001

A real-time HVAC system is proposed which implements real-time control of thermal environment for virtual reality. It consists of a pair of hot and cold loops that serve as thermal reservoirs, and a mixing box to mix hot and cold air streams flowing if from loops. Their flow rates are controlled in real-time to meet a set temperature and flow rate. A cascade control algorithm along with gain scheduling is applied to the system and test results shows that the closed-loop response approached set values within 3 to 4 seconds.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.276-282
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• 1996

This study dealt with the properties for fly ash of combined heat power plant and application for concrete industry. For this purpose, fly ash of ulsan combined heat power plant was analyzed for physical and chemical properties and tested the properties of the super flowing concrete. As results of fly ash, contents of SiO2 and Al2O3 in the fly ash of Ulsan were less than those of thermal power plant(Boryung), but contents of CaO were ten times as much as those of Boryung. In order to satisfy the properties of the Super Flowing Concrete using class C fly ash, mixing conditions were determined the optimum water-binder(w/b), volume ratio of fine aggregates(Sr) and coarse aggregates(Gv).