• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.73-80
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• 2013

An efficient synthesis of quinoxalines derivatives is described using magnetic material separated from coal fly ash. Coal fly ash is a waste material generated in huge amount by burning of coal for the generation of electricity in thermal power station. It contains $SiO_2$, $Al_2O_3$ and magnetic material in significant amounts, from which magnetic material was separated by using magnetic separation method. These separated magnetic material further characterized by XPS, XRD, EDS, FTIR, SEM, TEM and BET techniques. The merits of present method are mild reaction conditions, and also excellent yields and short reaction times.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.669-677
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• 2015

A mechanistic model for void fraction prediction with improved interfacial friction factor in nearly horizontal tubes has been proposed in connection with the development of a condensation model package for the passive auxiliary feedwater system of the Korean Advanced Power Reactor Plus. The model is based on two-phase momentum balance equations to cover various types of fluids, flow conditions, and inclination angles of the flow channel in a separated flow. The void fraction is calculated without any discontinuity at flow regime transitions by considering continuous changes of the interfacial geometric characteristics and interfacial friction factors across three typical separated flows, namely stratified-smooth, stratified-wavy, and annular flows. An evaluation of the proposed model against available experimental data covering various types of fluids and flow regimes showed a satisfactory agreement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.196-197
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• 2009

In Video, key frame generated from the scene change detection is to perform character recognition through the projections. The separation between the text are separated by a vertical projection. Phoneme is separated Cho-sung, Jung-sung, and Jong-sung and is divided 6 types. Phoneme pattern is separated to suitable 6 types through the horizontal projection. Phoneme are separated horizontal, vertical, diagonal, reverse-diagonal direction. Phoneme is recognized using the 4-direction projection and location information.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.383-390
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• 1997

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.459-466
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• 2017

Objective: This study examined two traffic signals with a countdown indicator in terms of driver's reaction time and subjective satisfaction score and their performance was compared with a standard traffic signal in driving simulation. Background: Dilemma zone is created when a traffic light changes at intersections. It often pushes drivers to rush in urgent and premature decision making whether to go or stop and thus induces unnecessary mental load among drivers, which may lead to sudden conflicts with following vehicles at intersections. Method: Forty college students (male: 20, female: 20) participated in this driving simulation study. Three traffic signals were employed: (1) standard traffic signal; (2) countdown-separated signal; and (3) countdown-overlaid signal. The countdown-separated and countdown-overlaid signals were designed to inform drivers of the remaining time of a green light before tuning to an amber light. Reaction times (sec) and satisfaction scores (7-point scale) for the two signals with a countdown indicator were compared with those for the standard traffic signal. Results: Reaction times of the countdown-separated (0.49 sec) and countdown-overlaid (0.43 sec) signals were significantly shorter than that of the standard signal (0.67 sec). Satisfaction scores of the countdown-separated (5.3 point) and countdown-overlaid (5.6 point) signals were greater than that of the standard signal (3.8 point). Lastly, the countdown-overlaid signal showed better performance than the countdown-separated signal, but their differences in reaction time (0.06 sec) and satisfaction score (0.3 point) were small. Conclusion: Traffic signals with a countdown indicator can improve drivers' reaction time and satisfaction score than the standard traffic signal. Application: Traffic signals with a countdown indicator will be useful for reducing the length of dilemma zone at intersections, by allowing drivers to predict the remaining time of a green light.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.153-167
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• 1995

Recycling is receiving increasing social attention today as our nation begins to grapple with the significant problems caused by huge amount of municipal solid waste. The topic of recycling is not simple but extremely complicated. This study attempts to provide basic data and policy options for expanding and improving separated collection and recycling in public residential areas, through three case study of apartment housing areas in Taegu Metropolitan City. The main results of this study are summarized as follows. For the significant period of time, all three case areas had in common the extreme difficulty in establishing and operating the system of connecting public participation, collection and storage, transportation, and actual recycling of materials because of a variety of problems involved in this process. Both amounts of and prices for collected materials fluctuated considerably over time mainly due to monthly changes in recyclable home materials and the dynamic nature of recycling markets. Public questionnaire survey revealed the very high level of participation in separated collection, not only because almost all respondents well understood the necessity and importance of recycling, but because they also knew how to do separated collection. But overall activities were rated low and most respondents suggested the enlargement of public participation, the improvement of collection and storage facilities, and collection transportation networks. In particular, most respondents had little experience of using recycled Products and used mainly reproduced soap and bathroom tissue. Furthermore, they were considerably unsatisfied with low variety and quality of recycled products, their high prices and low availability in the market. Finally potential policy options and activities for improving separated collection and recycling are suggested.

• Reproductive and Developmental Biology
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• v.34 no.1
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• pp.41-46
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• 2010

The objective of this study was to evaluated the efficiency of sperm cryosurvival using each extenders Triladyl and LEY containing egg yolk to the cryopreservation of separated sperm by percoll in miniature pig. The ejaculated semen from miniature pig was separated by 65% percoll and un-separated sperm as a control before freezing. The freezing of diluted semen added with Triladyl containing egg yolk and LEY solution (solution I: 11% Lactose or Triladyl + egg yolk; solution II: solution I + glycerol + OEP). Analysis of sperm ability was estimated by viability, capacitation acrosome reaction using chlortetracycline (CIC) the morphologic abnormality and hypoosmotic swelling test(HOST). The groups were designed that as separated sperm by Percoll with Triladyl(ST) or LEY(SL) for cryopreservation. And unseparated sperm with Triladyl(UT) or LEY(UL). As a results, the viability was higher significantly(p<0.05) in ST, SL, UT than UL extender. The morphologic abnormality was measured significantly (p<0.05) lower in ST than other extenders. The AR-patterned in CTC analysis was measured significantly(p<0.05) lower in SL and UL than other extenders. In conclusion, using Triladyl extender resulted in viability and morphology of separated sperm by percoll that were effective than using LEY extender, but it resulted in capacitation acrosome reaction was lower than using LEY extender.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.167-175
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• 2000

This paper describes the magnetic orientation of bull sperm separated into the head and the flagellum treated by DTT or heparin in a 5,400G static field. Semen samples collected from four bulls (Japanese Black) were mixed to the same sperm density. One percentage triton X-100 was used to extract the plasma membrane. The intact and demembranated sperm suspensions were treated with 20, 200, 2,000 mM DTT, 100, 1,000 or 10,000 units heparin solutions at $4^{\circ}C$ for 6 days. The decondensation of the sperm nuclei treated by DTT or heparin was examined by measuring the head area at 1, 3 and 6 days. After measuring the area, each sample was exposed to a 5,400G static magnetic field generated by Nd-Fe-B permanent magnets for 24 hours at room temperature. Results showed that the sperms were separated into the head and the flagellum through the DTT treatment. Almost of the separated heads showed that their long axis oriented perpendicularly to the magnetic lines of force, and most of the long axis perpendicularly oriented heads showed that their flat plane oriented perpendicularly in a 5,400G magnetic field. Also, the demembranation of the head tended to increase those perpendicular orientations, while those perpendicular orientations of the head declined with the decondensation of the sperm nuclei. These findings suggest that strong magnetic anisotropy for the perpendicular orientation of the long axis and the flat plane of the head occurs in the sperm nuclei in a 5,400G magnetic field. The separated flagellum showed lower parallel orientation, and the separated and demembranated flagellum showed parallel orientation to the magnetic lines of force in this magnetic field. These findings suggest that weak magnetic anisotropy of the parallel orientation of the flagellum occurs in the inside components in a 5,400G field.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.929-930
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• 2012

• Honam Mathematical Journal
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• v.28 no.1
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• pp.69-81
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• 2006

First, we give a complete description of the multiplication modules over local Dedekind domains. Second, if R is the pullback ring of two local Dedekind domains over a common factor field then we give a complete description of separated multiplication modules over R.