• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.23-29
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• 2008

Simple Keggin type tungsten and molybdenum heteropoly acids, H3PW12O40 and H3PMo12O40, were usedas water-tolerant catalysts for the oxidation of alcohols with 34% hydrogen peroxide in normal drinking water. Accordingto our findings, H3PW12O40 may be used as a simple, effective, and cheap catalyst for this type of transformation in nor-mal drinking water with excelent yields. Efects of diferent solvents at 25-80oC and changing concentration of catalystand substrate on the reaction progress were also studied.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.8 s.251
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• pp.741-748
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• 2006

This paper numerically investigates the effects of pass arrangement on the flow distribution characteristics and the performance of a multi-pass multi-branch heat exchanger. Four cases of pass arrangement (2, 4, 6, 8 pass) are chosen to select a proper pass arrangement. A JF factor is used as an evaluation characteristic value to consider the heat transfer and the pressure drop. The present results indicate that 4-pass heat exchanger shows the best performance, and the design parameters in 4-pass heat exchanger are optimized. The design parameters are the locations of the inlet, outlet and separator, and are optimized using a response surface methodology. The JF factor of the optimum model is increased by about 9.3%, compared to that of the reference model (2-pass heat exchanger).

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.203-204
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• 1995

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.2
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• pp.91-97
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• 2002

The present study concerns an experiment on the supply-air control in variable air volume (VAV) system with a Pl control logic. A thermal chamber with a Pl control logic is constructed to verify the previously suggested multi-zone model. The stratified thermal model is adopted in the control logic for a thermal chamber cooling test. The effects of taler- mal parameters and control parameters such as supply air temperature and Pl control factor are investigated by implementing the thermal chamber cooling test. The experimental results obtained show that the transient behavior of the air-conditioned space temperature are in good agreement with the simulation results of the stratified thermal model.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.2
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• pp.74-79
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• 2009

The performance of cryogenic refrigerator greatly depends on the effectiveness of heat exchanger, which generates major entropy at low temperature. There are numerous types of heat exchanger available, but it is not easy to apply most of them to cryogenic application because the cryogenic heat exchanger must have high effectiveness value as well as small conduction loss in the environment of considerable temperature difference. In this paper, two kinds of heat exchanger are noticeably introduced for high-effectiveness miniature cryogenic recuperator(recuperative heat ex-changer). Also, the flow mal-distribution problem, which is a critical issue of performance deterioration in a high-effectiveness recuperator, is addressed with simplified model, and its alleviation method is discussed.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.409-420
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• 1999

$\ulcorner$GANPYUN CHOSUN YORI-JEBUP$\lrcorner$,a book of cooking was written in Korean in 1934. The kinds of food were analyzed of cooking method, materials, measuring unit of materials by this book. Findings from this book are summarized as follows: 1. There were 8 kinds of Bap and 18 kinds of Zook. 2. There were 31 kinds of Korean Soup. 10 kinds of Ziggae, 4 kinds of Jun-gol. 3. There were Side-dishes including 6 kinds of Jim, 5 kinds of Jijimee, 7 kinds of Sanjuk, 9 kinds of Junyua. 18 kinds of Na-mool, 4 kinds of Moo-chim, 3 kinds of Ho, and 15 kinds of Po and were 8 kinds of dry side-dish. 4. Utensil to be used che(sieve), sot(pot). nambi(pan), Sugarak(spoon), and yang peon(bowl). 5. The measuring units were various. for example mal, dei, hob, etc. 6. The processing of cooking included preparation and boiling process. The processing of preparation were puting. mixing, and being cold, and the processing of heating were steaming and boiling.

• Proceedings of the Korea Association of Information Systems Conference
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• 2005.12a
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• pp.235-248
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• 2005

This paper examines internet shopping mall e-loyalty behaviors. Conceptually, the paper relied on the relatively established literature on ' traditional ' store image and technology acceptance research. And proposes an integrated model including factors on customer e-loyalty in shopping environment. For this purpose, internet shopping mall user's image is proposed to affect trust, and commitment, and consequently to influence customer loyalty behaviors. The empirical results indicated that shopping mal image take significant effect on trust and customer loyalty behaviors. And commitment variable are effective mediators linking internet shopping mall user's trust and their loyalty behaviors. The proposed model and empirical results would contribute to setting up strategy shopping mall industry, and also to future research in information systems and internet marketing.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1419-1427
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• 2008

This paper shows the kernel Poisson regression which can be applied in the claims reserving, where the row effect is assumed to be a nonlinear function of the row index. The paper concentrates on the chain-ladder technique, within the framework of the chain-ladder linear model. It is shown that the proposed method can provide better reserve estimates than the Poisson model. The cross validation function is introduced to choose optimal hyper-parameters in the procedure. Experimental results are then presented which indicate the performance of the proposed model.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.964-966
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• 1998

The TC curve of recloser which used in KEPCO's distribution line is a little different in a pattern with the TC curve of sub-station OCR. So it sometimes fails in protection coordination. And the recloser sometimes does mis-open/close owing to the inrush current of CB reclosing when a fault occurred on the source-side of the recloser. The mis-open/close is another trouble maker. This Paper Present a new delay TC curve of recloser which has the same pattern with the TC curve of OCR, and a new instantaneous TC curve of recloser which doesn't mal-function to the inrush current. In addition, this paper present another two TC curves for the serial positioning of 2 reclosers. So we accomplished the simple protection coordination of OCR-recloser-fuse.

• Biomedical Science Letters
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• v.15 no.1
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• pp.73-80
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• 2009

Bloodstream infections (BSI) are caused by planktonic microorganisms, sometimes leading to serious infections such as bacteremia and sepsis. BSI occurs more frequently to the patients wearing the central venous catheter (CVC). The ciprofloxacin-incorporated CVC (CFX-CVC) has been reported previously to possess antimicrobial activity. In this study, the antibacterial activity of CFX-CVC and its mechanism against planktonic BSI cells were explored by using the shake flask test and by examining the release rate of 260 nm-absorbing substances from the bacterial cells indicative of the membrane damage of the bacterial cells. CFX-CVC reduced more than 99.9% of the viable planktonic BSI cells demonstrating its potent antibacterial activity. It provoked bacteriolysis causing leakage of a large amount of 260 nm-absorbing materials from the planktonic bacterial cells like S. aureus and E. coli. These results provide evidence that the antibacterial activity of CFX-CVC came from the inhibition of the stability of the planktonic bacterial cells.