• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.254-259
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• 1996

The hydraulic tests for 16$\times$16 JDFA were performed to obtain the pressure loss coefficients using the FACTS. The pressure loss coefficients are calculated by converting the each properties of experimental values for inlet region, mixing vane grid, outlet region and core region by performing a power fit of the pressure loss coefficient values to the corresponding Reynolds number. The test results are compared with the existing calculated values and evaluated by using the CALOPR code in terms of pressure drop. It is turned out that the differences between the test results and the calculated values are about by 3.8% for the pressure loss coefficients and by 8.5% for the pressure drop.

• Journal of Environmental Impact Assessment
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• v.20 no.5
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• pp.697-703
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• 2011

The purpose of this study aims to preserve biodiversity in increasingly fragmented green patches for spatial analysis of planting on the eco-corridors and to optimize the target species, the location, width, cross section of the eco-corridors. It was suggested that eco-corridors should have to planned at early stages of road planning so that the number and locations of eco-corridors in advance. Ecological corridor is the facility to connect two habitats fragmented by road, dam, housing and industrial area. And, everyone agree that ecological corridor is important useful structural component that help animal movement in fragmented landscapes. However, ecological corridors have many problems of the recorded the size of corridor, planting species to nearby exiting vegetation species and structure. The most important facts that there are no consideration for location of animal migration and behavior using eco-corridors. This study was carried out to spatial analysis of eco-corridors location, satellite data and GIS were used to analyze for searching optimum location of the eco-corridors.

• Journal for History of Mathematics
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• v.19 no.4
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• pp.13-30
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• 2006

The purpose of this study is to investigate the meaning and roles of rhymes in oriental mathematics. To do this, we consider the rhymes in traditional chinese, korean, indian, arabian mathematical books and the mathematical knowledge which they implicate. And we discuss the reasons for which they were often used and the roles which they played. In addition, we suggest how to use them in teaching mathematics.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.167-170
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• 2001

A low power pulse Doppler radar should integrate a large number of data to provide a required maximum detectable distance. Doppler filter needs a window that has good out-of-bard rejection level to maintain high dynamic range. From these facts, we can apply decimation and presumming to increase the speed of Doppler processing. This Paper investigates the efficiencies of several decimation methods and the loss of presumming. And I propose a method to increase processing speed but to maintain the maximum detectable distance.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.6
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• pp.296-302
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• 2001

This paper proposes a SSSC based on multi-bridge inverters. The dynamic characteristic of the proposed SSSC was analyzed by EMTP simulation and a scaled hardware model, assuming that the SSSC is inserted in the transmission line of the one-machine-infinite-bus power system. The proposed SSSC has 6 multi-bridge inverters per phase, which generates 13 pulses for each half period of power frequency. The proposed SSSC generates a quasi-sinusoidal output voltage by 90 degree phase shift to the line current. The proposed SSSC does not require the coupling transformer for voltage injection, and has a flexibility in operation voltage by increasing the number of series connection.

• Journal of the Ergonomics Society of Korea
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• v.3 no.1
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• pp.3-11
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• 1984

This study aims to investigate the effects of the size of operator's hand and the use of foot on the production quantity and product quality. To find out the facts the survey is conducted by measuring the hand size for the worker who is randomly chosen and by grouping them into the large hand size group and small hand size group on the base of the measuring data. The grouped operators are assigned to their job as usual, and their daily production quantities and qualities are measured. The survey shows that the production quantity of the small hand group are higher than the large hand group, and the number of defects of the small hand group are less than the large hand group.

• ETRI Journal
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• v.28 no.2
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• pp.227-230
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• 2006

There has been a growing need for increased capacity in cellular systems. This has resulted in the adoption of the code division multiple access (CDMA) system as a multiple channel access method. Thus, it is important to obtain the phase offsets of binary codes in the CDMA system because distinct phase offsets of the same code are used to distinguish signals received at the mobile station from different base stations. This letter proposes an efficient algorithm to compute the phase offset of a binary code in the CDMA system through the use of the basic facts of number theory and a new notion of the subcodes of a given code. We also formulate the algorithm in a compact form.

• Journal of the Korean Society of Safety
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• v.7 no.3
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• pp.3-13
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• 1992

In recent years, the study about the high efficiency and low fuel consumption of the internal conbustion engine has been mainly proceeding. To achieve these goals, the improvement of combustion process in Sl engine and the use of substitute energy are suggested. When the methanol blend fuel Is used, the combustion rate of the initial ignition is diminishing by high latent evaporation of methanol. But it attracts the attention because of the high octane number, and lean mixture peculiarity. Considering these facts, the gasoline-methanol blend fuel In engine operation has been used to compare and analyze the pressure development, rate of heat release, mass burned fraction, and combustion process. The results of experiment show the power increase, lean combustion and low harmful component of emission.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.11
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• pp.531-535
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• 2000

A method to compute the reactive powers of the added buses by the decoupled UPFC model for the optimal voltage profile is presented, by which the voltage magnitudes of PQ buses can get closer to the reference value(usually one p.u.). The performance index for assessing how much the voltage magnitude is closer to the reference value is defined as the squared sum of the present voltage minus the reference voltage multiplied by the weighting number associated with the relative importance of the buses. Numerical example in a 10-unit 39-bus power system with 2 UPFC's shows that the performance index can be very much reduced by operating many UPFC's with the reactive powers for the optimal voltage profile proposed in this paper.

• Journal of Korea Port Economic Association
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• v.21 no.3
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• pp.191-217
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• 2005

Ninety percent of an average Chinese manufacturer's time spent is on logistics. Therefore, logistics presents the greatest challenge for multinational companies conducting businesses in China. Although more than 18,000 registered logistics companies exist in China, 85 percent of their revenues are generated from basic trucking and storage services. These facts indicate that China will need increasing presence of high-quality foreign 3PL providers, who are able to provide sophisticated IT systems, industry/operational expertise, standardized operating processes, and international networks, compared to their Chinese counterparts. However, they are facing complicated array of laws and regulations as well as difficulty of finding qualified people to fulfill these needs. There are a number of foreign 3PL providers engaged in China's logistics sector to reap a huge opportunity. Nevertheless, many 3PL foreign providers are still cautious about making large investments. Thus they arelooking for alliances that can provide complementarities instead. Another salient feature of strategy is to take over the transportation assets and warehousing of major Chinese manufacturers and distributors.