• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.14-16
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• 2007

본 논문에서는 UHF대역 RFID 통신 시스템 간에 발생하는 리더 간섭을 방지하기 위한 전파흡수체를 설계 및 제작하였다. 먼저 자성손실 재료인 Amorphous와 지지재인 CPE(Chlorinated Polyethylene)를 이용하여 조성비별 전파흡수체 샘플을 제작하였고, 이 전파흡수체 샘플로부터 구한 재료정수를 이용하여 시뮬레이션을 한 결과 최적의 조성비가 Amorphous: CPE = 80 : 20 wt.% 임을 확인하였다. 그리고 시뮬레이션 결과를 토대로 전파흡수체를 실제작하여 전파흡수능을 비교 ${\cdot}$ 분석하였다. 그 결과 Amorphous : CPE = 80 : 20 wt.%의 조성비 일 때, 두께 4mm 의 전파 흡수체가 860 MHz ${\sim}$ 960 MHz의 주파수 범위에서 전파흡수능 20 dB 이상의 특성을 얻음으로써 UHF대역의 RFID 리더 간섭을 억제할 수 있음을 확인하였다.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.691-694
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• 2008

Spray characteristics of the APU simplex fuel nozzle are investigated. Four flight conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power are used as spray experimental conditions. Spray visualization was performed by using ND-YAG laser. Droplet size and velocity were measured by using PDPA(Phase Doppler Particle Analyzer) system. From the test result, SMD is 100 ${\mu}$m�� and velocity is 10 m/s at 20,000 ft idle condition. In this condition, flame unstability could be occurred due to the higher drop diameter. Therefore it is necessary to decrease the droplet diameter in the high altitude condition.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.5
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• pp.552-557
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• 2014

The objective of the This study is to access the speed performance employing the sea trial test and CFD with the our own designed and manufactured one-man boat. The overall design process including hull form design was explained. The sea trial was carried out with a manufactured boat in the clam sea. Brake power at the design speed of a boat through the sea trial was measured as 1680 W. The flow computation was conducted considering free surface and dynamic trim using a commercial CFD code(STAR-CCM+). The result of computation provided the information that residual resistance is bigger than fraction's at design speed. The total efficiency were predicted based on the sea trial and CFD. The Total efficiency was divided into shaft efficiency and quasi-propulsive efficiency. By using quasi-propulsive efficiency, it becomes possible to predict speed performance of boat in future. The results can provide information regarding hull form design, performance analysis and development of a boat in future.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.335-340
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• 2016

This study was conducted to find out the most suitable DNA isolation methods for PCR detection of foodborne pathogens. Four DNA isolation methods including Universal Genomic DNA Extraction Kit (TaKaRa), PrepMan Ultra (Applied Biosystems), boiling method and alkaline lysis method (w/PEG) were tested and compared. The Universal Genomic DNA Extraction kit (TaKaRa) was considered as the more efficient isolation method for Escherichia coli O157:H7 and Staphylococcus aureus in lettuce, fish and beef. Meanwhile to detect the foodborne pathogens directly from foods without enrichment, the four different buffers such as double-distilled water, saline, glycine-saline, glycine-saline with Tween-20 and beef extract were also evaluated. As a result, saline was more suitable buffer for E. coli O157:H7. And double-distilled water was more suitable buffer than saline for S. aureus, respectively

• Journal of Agricultural Extension & Community Development
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• v.20 no.1
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• pp.265-297
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• 2013

This study performed quality study to examine cognition and experience as it is about husband role of wife's perception in rural multicultural family. Specifically the results of in-depth interviews with 13 females in rural multicultural family was analyzed through phenomenological method. The results were as followings: first, wife's cognition about husband role in rural multicultural family, they were 'nice and warm man', 'no special thought', 'clean and cool looking man', 'man without straitening wife', 'husband taking care of housekeeping', 'having independent family' and 'strong responsibility to children'. Females in rural multicultural family did not deeply think about husband's role at international marriage, but it could be known that vague longing for rich country, Korea by Korean wave and its expectation continued to expectation on husband. Second, they were 'good-tempered and nice to me', 'adjust to me', 'irresponsibility and apathy', 'cannot lean to him', 'no housekeeping', 'intermediate role between his family', 'more taking care of children, parents and relatives', 'drink, gambling and violence'. The experience of husband role was little different from cognition of husband role by females in rural mulitcultural family.

• Korean journal of applied entomology
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• v.52 no.2
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• pp.71-74
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• 2013

The moving period and overwinteing site of Scrobipalpa salinella (Zeller) were investigated in Gimje, Jeonbuk, and Shinan, Jeonnam in the glasswort field. Densities of Scrobipalpa salinella larvae were started to increase from mid-September in halophytes, such as Suaeda asparagoides, S. japonica, and S. maritima, rather than glasswort. S. salinella was overwintering inside the halophytes in old larva. Density ratio of overwintering S. salinella in Suaeda asparagoides, S. japonica, and S. maritima were 20.5, 28.4 and 51.1%, respectively. Overwintering population was highest in S. maritima among halophytes. The occurrence of first adult in the next spring was from April 19 to April 20 in Gimje, Jeonbuk, and Shinan, Jeonnam.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.238.2-238.2
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• 2007

• Research in Mathematical Education
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• v.6 no.1
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• pp.29-38
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• 2002

The purpose of this paper was to examine early numerical representations between American and Korean children. Fifty-five first graders (35 Korean and 20 American) participated in the study. According to the findings of the current study, the author concluded that the Korean children had a stronger conception of base ten representations of numbers than that of the American children. The Korean children used various strategic reasoning such as decomposition and recomposition on the basis of base 10 structure to solve addition and subtraction problems effectively. However, the author cannot conclude that language differences would be the largest factor that would make Korean children sapient in the representations of base ten structures.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.180-183
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• 2002

이 논문의 목적은 중고가(15-20 만원) 건강제화상품의 실제 수요자 그룹(40세 이상의 일반인 및 발병 관련 환자 포함)을 설정하고 이들의 발 측정 자료를 근거로 하여 기존의 건강제화용 LAST를 체계적으로 분석하여 주요 LAST 설계인자들을 도출하고, 이들 설계인자들을 고려하여 건강 제화용 라스트를 개발하는데 있다.

• Electronics and Telecommunications Trends
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• v.20 no.6 s.96
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• pp.110-121
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• 2005

LAN에서 사용되던 이더넷 기술은 단순성과 낮은 투자/운용 비용으로 인하여 WAN/MAN 영역으로까지 사용이 급속도로 확산되고 있다. 캐리어급 이더넷 OAM 기술은LAN 중심의 이더넷 기술을 캐리어급 망에서 사용할 수 있게 해주는 주요 기술로IEEE, ITU-T, MEF 등 표준화 기구에서 이에 대한 표준화가 진행되고 있다. 본 논문에서는 크게 PHY 계층과 MAC 계층의 두 부분으로 구성된 이더넷에서 단일 링크 상에서 발생하는 동작들을 처리하는 ETY 계층 OAM 기술과 다중 링크로 연결된 이더넷 경로상에서 발생하는 동작들을 처리하는 ETH 계층 OAM에 대한 기술을 분석하여 정리한다.