• 한국지반공학회논문집
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• 제19권2호
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• pp.57-64
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• 2003

지진하중조건에서 포화된 모래의 액상화 가능성은 심도 있는 연구가 진행되어 왔다. 이러한 연구에서 대표적인것은 실험실에서 반복삼축압축시험에 의하여 모래의 반복강도를 결정하는 것이다. 본 연구는 재성형된 포화 균등모래의 액상화 특성에 있어서 시편의 성형방법에 따른 영향을 검증하기 위하여 수행되었다. 건조시료의 공기중낙하다짐, 습윤층다짐, 습윤진동층다짐 등 3가지 방법에 의하여 동일한 밀도로 다짐된 포화된 균등한 모래에 대하여 삼축압축시험이 수행되었다. 같은 밀도에서 다른 방법에 의하여 성형된 포화된 균등한 모래의 액상화 저항특성인 반복응력비는 크게 다른 것으로 확인되었다.

• 조명전기설비학회논문지
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• 제22권8호
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• pp.59-66
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• 2008

디지털 기술 기반의 차세대 변전시스템의 시스템 성능 검증을 위해 변전소 전력설비의 보호에 있어 가장 중요한 보호요소 중 하나인 차단기 실패 보호 IED를 대상으로 하는 IEC 61850 시스템 성능 시험 절차서를 구현하였다. 디지털 변전소에 대한 통신규격이 단일화되고 시스템이 디지털화됨에 따라 IED들은 상호 통신이 가능해지게 되었으며, 따라서 단일 IED의 전기 접점을 통해 이루어지던 예전의 시험방식에서 네트워크를 통한 시스템 차원의 시험방식으로 변화가 필요하게 되었다. 본 논문에서는 차단기 실패 보호 IED를 시스템적으로 시험할 수 있도록 UML을 이용한 성능시험절차서의 구현내용을 보여주고자 한다.

• 품질경영학회지
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• 제49권1호
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• pp.47-60
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• 2021

Purpose: This study proposes methods and procedures for evaluating imaging security systems quality of cabinet x-ray screening system to enhance performance certification technology. Also, conducted a comparative analysis of the literature of test-kit for imaging security quality evaluation. Methods: Comparative analysis of the test-kits and related documents for image quality assessment of cabinet x-ray screening equipment. This allows assessment items were selected and the methods for each assessment item were proposed. In addition, the configuration method of the assessment team was established by applying the technology readiness assessment(TRA). Results: Four of the assessment items were selected when estimate image quality by a comparative analysis of literature. For each assessment item, the evaluation method and minimum level of availability were determined. Finally, this paper proposes an imaging quality assessment of cabinet X-ray imaging security systems. Conclusion: Development of imaging security systems evaluation procedures for cabinet X-ray screening systems can be help improve performance certification of aviation security equipment.

• 임상간호연구
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• 제27권2호
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• pp.179-186
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• 2021

Purpose: The purpose of our study was to identify the bleeding risk factors and to validate the safety of shortening the bed rest time after bone marrow examination in pediatric hemato-oncologic patients. Methods: From July 2019 to September 2020, 145 patients were enrolled from a single center. Medical records were reviewed retrospectively. Descriptive statistics were presented, and the data were analyzed using 𝑥²-test, Fisher's exact test, and a logistic regression. Results: After two hours of bed rest, most of the patients (91.7%) did not have bleeding complications, and only 8.3% of the patients had a minor bleeding. The rate of major bleeding complications, including hematoma, retroperitoneal hemorrhage rate was zero. The bleeding complications was frequently found on bilateral procedures than unilateral procedures and the difference were statistically significant (p<.05). Conclusion: Two hours of bed rest time after bone marrow examination could be safe and adequate in pediatric hemato-oncologic patients.

• 아동학회지
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• 제29권6호
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• pp.163-176
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• 2008

The purpose of this study was to develop a standardized performance style Multiple Intelligences Test for preschoolers(MIT-P). A total of 270 preschoolers(3~5-years-old) participated in this study. Tools and procedures were developed to measure performance in 7 areas of multiple Intelligences(linguistic, mathematical, science, social, music, art and kinesthetic). The final test set included 138 items. Reliability of the MIT-P was relatively high(Cronbach alpha =.92). Intercorrelations among measures of the 7 areas indicated construct validity. Based on these results, the pilot study of MIT-P is considered adequate to form the basis of a new test that would help teachers and parents to identify children's strengths and weaknesses and may be useful for educational planning.

• 한국추진공학회지
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• 제2권2호
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• pp.108-117
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• 1998

엔진 내구성시험(AMT : Accelerated Mission Test : 또는 임무 가속시험) 기법을 이용한 엔진 부품의 국산화에 따른 품질 보증 시험이 수행되었다. 엔진 내구성시험 기법은 엔진의 개발/구성품 개량, 부품의 기술변경에 따른 인정시험이나, 입증시험을 위한 시험방법으로 1976년부터 적용되기 시작하였다. 본 논문은 국내에서 수행되었던 시험경험을 바탕으로 아직 국내에서 생소한 내구성시험에 대한 개념, 시험수행 절차와 방법 그리고 시험평가 수행 방안을 제시하였으며, 이를 통하여 엔진 부품의 국내 개발/생산시 품질인증을 위한 시험/평가 가능성을 제시하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.124-127
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• 2004

This study is to investigate the bond characteristics of glass fiber reinforced polymer(GFRP) reinforcing bars in concrete by pullout test experimentally. Three different types of GFRP bars with different surface deformations were considered in this study. Also, standard deformed steel reinforcing bar with or without epoxy-coating were included for the comparisons of bond strength. All test procedures including specimens preparation, test apparatus and measuring devices were made according to the recommendation of CSA(Canadian Standards Association) Standard S806-02. From the test results, it was found that small surface indentations contributed to increase the bond strength of GFRP bar significantly. Based on the limited test results till now, the bond strength of GFRP bar with sand-coated deformation commercially available in foreign market is around $80\%$ of that of steel deformed bars.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.205.1-205.1
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• 2011

This study concerns a low head and kaplan turbine efficiency measurement using the acoustic scintillation flow meter(ASFM). The ASFM is one of absolute discharge measurement methods because it measures velocity-area of discharge with couples of transducers. This study shows that the highest efficiency of turbine is 87.7% and the efficiency is 85.8% in the rated output(600kW). The test result is reliable because the efficiency trend from this test is similar to the result of index test conducted in 1986. In this paper, the principle, measurement methods, application and test procedures of the test are discussed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.220-223
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• 2007

Acoustic test of the payload fairing of Korea satellite launch vehicle was conducted to verify the performance of acoustic protection system installed inside the payload fairing. This paper briefly introduces the acoustic test procedures and its results. Overall 148 dB acoustic loads were exerted on the payload fairing structures which mated with the upper stage structure of the launch vehicle. In order to verify the increase of insertion loss by the acoustic protection system, two kinds of test were performed. One is conducted with acoustic protection system and the other without acoustic protection system. Internal acoustic loads as well as external ones were measured and the measured insertion losses were compared with the requirement. The results showed that the acoustic protection system increases the insertion loss by more than 6 dB above 125 Hz. They also indicated that some design modification of Helmholtz resonator array is required to increase the insertion loss at a cavity resonant frequency.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.48.1-48.1
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• 2011

In this presentation, We monitored weather data, such as global irradiance, ambient temperature, temperature of PV module, relative humidity and windspeed for 2 years, for determining accelerated test condition. then, we determined the temperature limit of accelerated test through weather data and FEM analysis. Detailed procedures will be summarized in this work. After analysing outdoor stress such as thermal stress, we decided main failure modes and mechanisms of PV module, especially solder joint of ribbon wire. we carried out the measurement of material properties such as thermal expansion coefficient for planning of accelerated test. we designed accelerated test based on FEM analysis results. we carried out thermal cycling test with 1 cell mini module for 3 months. We monitored the change of electrical performance every 1 week such as Voc, Isc, Pmax, etc. and then, we analized the ribbon wire/electrode intefaces. Detailed results will be summarized in this work.