• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.569-572
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• 2009

The numerical simulations of hydrocarbon fueled scramjet engine have been studied less than them of hydrogen fueled scramjet engine. Ethylene is selected in hydrocarbon because of its good thermochemical properties and a direct-connect scramjet combustor at the American Air Force Research laboratory is taken to a two-dimensional simulation model. Ignition time delay of ethylene was monitored and air throttling was imposed to generate ignition inside the model scramjet.

• Journal of Korea Trade
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• v.23 no.7
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• pp.147-155
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• 2019

Purpose - As the U.S.-China trade war has become considerably worse, the Chinese government is considering applying non-tariff barriers to trade, especially local contents rule. The main purpose of this research is to check whether it is suitable for Korean investors to invest in the current Chinese capital market. Design/methodology - In order to check the stability of the recent Chinese capital market, we investigated the behavior of foreign equity investment (including Korean equity investment) in the Chinese capital market after China announced the Shanghai-Hong Kong Stock Connect (SH-HK Connect). In this paper, we researched whether international portfolio investment would or would not contribute to an increase the volatility of an emerging market's stock market (Chinese capital market) when foreign investors make investment decisions based on the objective of short-term gains by rushing into countries whose markets are booming and fleeing from countries whose markets are falling. Findings - The empirical results indicate that foreign investors show strong, negative feedback trading behavior with regard to the stock index of the Shanghai Stock Exchange (SSE), and when the performance of foreign investors in the Chinese stock market was fairly good. Also, we found evidence that the behavior of foreign investors significantly decreased volatility in SSE stock returns. Consequently, the SH-HK Connect brought on a win-win effect for both the Chinese capital market and foreign investors. Originality/value - It appeared that the Chinese capital market was very suitable for Korean investors after the China's declaration of the SH-HK Connect. However, the win-win effect was brought on by the Chinese government's aggressive capital control but the capital controls could possibly cause financial turmoil in the Chinese capital market. Therefore, Chinese reform in industrial structure and the financial sector should keep pace with suitable capital control policies.

• Plant Resources
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• v.7 no.3
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• pp.233-237
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• 2004

This study was conducted to develop effective production system in greenhouse for leaves and stems of Angelica acutiloba by using connect pots in 2003 and 2004. Seed germination rate and plant biomass of Angelica acutiloba collected in 2004 were higher than those harvested in 2003. Germination rate of Angelica acutiloba seeds collected in 2003 was 10％, while germination rate of seeds collected in 2004 was above 90％. Especially, plant growth and yield of Angelica acutiloba grown in connect pots sized with 4 ${\times}$ 4 ${\times}$ 5cm(length ${\times}$ width ${\times}$ height) were the highest. These results indicate that leaf and stem production of Angelica acutiloba can be improved by using connect pots and optimizing seed collecting time in greenhouse.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.5
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• pp.41-45
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• 2002

Asymmetric bilayered ShuffleNet topology is used to implement the WDM cross-connects as central hubs. The advantage of the implementation is the reduction of the total number of WDM cross connects required by a half, the average number of hops, and average delay.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.04a
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• pp.211-218
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• 1997

Analysis of structures are usually executed under the assumption that connections are either ideally pinned joint or fully rigid joint. But in general all structures is connected under the semi-rigid connections. Semi-rigid connect ions have demerits that is simplification work on connection's behavior, moment-rotation relationships of connect ions , apprehension of nonlinear analysis etc. On the other hand there is merits that is improvements of serviceability, economic efficiency, construction in predicting real behavior frames. This study is to make model of connect ions by based on experimental study and after analysis on frames considering characteristics of semi-rigid connections. semi-rigid connection's influence on the behavior of structures and fundamental data on application of structures that is connected between S H S column and H beam is exhibited.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.2
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• pp.81-89
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• 2022

Purpose: Wireless endodontic handpieces (WEH) are widely used in dental clinics due to their convenience and portability. This study aimed to compare the vibration magnitudes and patterns generated by five WEH. Materials and Methods: Vibration acceleration of five WEH (X-Smart IQ, E connect S, Endo A Class, ENDOIT, and TRAUS ENDO) in the rotary and reciprocating motion was measured with accelerometer The average vibration acceleration was analyzed using the t-test, Welch's ANOVA test, and Dunnett T3 test at P < 0.05. Results: In all WEH, the average vibration acceleration in reciprocating motion was significantly higher than that in rotary motion (P < 0.001). In rotary motion, repeated vibration graphs of constant amplitude were obtained without sudden changes in the magnitude of vibration, and the average vibration acceleration value was high in the order of X Smart IQ, Endo A Class, ENDOIT, E Connect S, and TRAUS ENDO (P < 0.001), there was no statistically significant difference between X Smart IQ and Endo A Class. In reciprocating motion, a vibration graph was obtained in which large amplitude peaks appear at specific points within one cycle are repeated. The average vibration acceleration value was highest in the order of X Smart IQ, E Connect S, Endo A class, ENDOIT, and TRAUS ENDO (P < 0.001). Conclusion: Regardless of the type of WEH, greater vibration occurred in the reciprocating motion than in the rotary motion (P < 0.001). In the reciprocating motion, there was a difference in vibration for all handpieces (P < 0.001).

• Journal of Electrical Engineering and information Science
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• v.3 no.3
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• pp.336-341
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• 1998

We describe the architecture of an optical cross-connect (OXC) which is modular in structure and is able to be upgraded to a virtual wavelength path by adding wavelength converters. The additional feature of the OXC is the all-optical nature. It can be implemented with commercial components including mechanical optical switches. As a result of the test on the experimental OXC, it has been shown that 2.5 Gb/s signal can be transmitted via the OXC through 100 km length o an ordinary single mode fiber with 3 dB penalty.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.215-218
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• 2002

This paper use the USB Bulk Communication for interface of eMbedded system. But existing USB Bulk Communication have defects, it only connect point to point. And then this paper defines several command packet to improve such defects. So it improves Data Packet Layer of existing USB Bulk Communication. And then this paper make up for it's defects and implements multiplex communication Protocol in order to connect many eMbedded systems.

• Education of Primary School Mathematics
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• v.5 no.1
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• pp.1-11
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• 2001

The purpose of the study is to introduce how tessellation can be used and integrated to connect geometry to pattern in elementary mathematics educations. Tessellation examples include transformations such as translational symmetry, rotational symmetry, reflection symmetry, and glide reflection symmetry. In addition, many examples of tessellation using softwares such as Escher, TesselMania!, and LOGO programs. Further, future study will continue to foster students and teachers to try to construct their alive mathematics knowledge. The study of geometry and patterns require a rich teaching and learning environment provided by in-depth understanding of thinking connections to objects in real world.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.160-162
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• 1996

This paper is one-phase fault current analysis of 154kV underground transmission power cable. Its purpose is to gain knowleges of connect ing the CCPU and to show the merits as its method. There are many methods of connect ing CCPU, i.e, a conventional method, CIGRE method, interconnect ion between sheaths with grounding, and interconnect ion between sheaths without grounding. These methods will be compared in this paper.