• 한국세라믹학회지
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• 제40권1호
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• pp.104-108
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• 2003

스크래칭 시험(scratching test)을 이용하여 단결정 실리콘의 수직하중에 대한 마찰계수, AE(Acoustic Emission) 신호와 긁힌 자취의 미세균열을 관찰하고 그 결정구조를 분석하였다. 스크래칭 시험은 하중인가속도(loading rate)를 100N/min으로 하고 스크래칭 속도(scratching speed)를 1, 3, 6, 10mm/min의 4가지로 하여 최대 30N이 될 때까지 행하였다. 그 결과, 수직하중 또는 스크래칭 속도가 증가할 때 마찰계수, AE, 균열밀도는 증가하는 경향을 나타내었다. 스크래칭, 자취에 대한 마이크로 라만 분광법을 이용한 결정구조 분석결과, 스크래칭 속도가 느린 조건에서 압력인가에 따른 실리콘의 다이아몬드 구조에서 다른 고압상의 구조로의 상전이 현상을 관찰할 수 있었다.

• Archives of Pharmacal Research
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• 제26권2호
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• pp.143-146
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• 2003

Triterpenoids, ursolic acid (1) and 23-hydroxyursolic acid (2) were obtained from the hydrolysis of BuOH fraction of Cussonia bancoensis extract to test anti nociceptive and anti-inflammatory effect of C. bancoensis (Araliaceae). Compound 1 and 2 exhibited anti-nociceptive effects, which were determined by acetic acid-induced writhing test and hot plate test. The effect of 2 was much more potent in acetic acid-induced writhing test than in hot plate test. Compound 1 and 2 significantly inhibited 1％-carrageenan-induced edema in the rat. These results suggest that the two triterpenes, ursolic acid and 23-hydroxyursolic acid, are responsible for the antinociceptive and anti-inflammatory effect of C. bancoesnsis.

• 한국통신학회논문지
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• 제30권6C호
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• pp.532-540
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• 2005

이 논문에서는 새로운 약신호 검파 기법을 얻어, 그 기법과 국소 최적 검파 기법을 바탕으로 순차 검파 방식을 이끌어낸다. 먼저, 1부에서는 새로운 약신호 검파 기법을 제안하고, 흥미로운 문턱값 성질을 몇가지 밝히며, 여러 가지 잡음 분포에서 문턱값 보기를 다룬다. 한편, 2부에서는 제안한 순차 검파 방식의 성능을 고정 표본 검파 방식, 순차 확률비 검파 방식, 끝을 자른 순차 확률비 검파 방식의 성능과 견주어 본다.

• 한국군사과학기술학회지
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• 제22권5호
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• pp.637-643
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• 2019

Wind tunnel testing for flow-through model is necessary for performance prediction of an aircraft with air-breathing jet engine. Internal drag correction and wall correction are performed to acquire preciser wind tunnel test data. Many test runs are generally required to correct internal drag and wall interference in wind tunnel test. In this study we investigated more effective correction schemes using the response surface method. Even though the number of tests required for these schemes was much smaller than that for conventional methods, the differences between corrections using these schemes and conventional methods were similar level with the uncertainty of measurement except for the data near the boundaries.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.870-875
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• 2023

In this paper, we analyzed the revised guidance on electromagnetic (EM) interference qualification of Regulatory Guide 1.180 (Revision 2), which is published by the U.S. Nuclear Regulatory Commission for electromagnetic compatibility qualification for nuclear safety, by comparing it with that of the previous version. We confirmed that the test methods and the acceptance criteria of both CE101 and CE102 tests for conductive emission and RE102 test for radiating emission are changed in the recently revised Regulatory Guide 1.180 (Revision 2). Furthermore, we found that the revised Regulatory Guide 1.180 provides flexibility in the use of alternative methods for EM interference (EMI) qualification, in that a mix of the various base-standards is technically allowed. In addition, the primary revision of the updated Regulatory. Guide 1.180 is that MIL-STD-461G is to be adopted as the latest base-standard, instead of MIL-STD-461E. To evaluate the influence on EMI qualification for nuclear safety due to the endorsement of MIL-STD-461G, we thoroughly analyzed the modifications in the acceptance criteria and test methods for EMI qualification, and then validated the analyzed effect on the EMI qualification, which is caused by the revision of MIL-STD-461, by performing electromagnetic simulation for equipment under RE102 test.

• 대한수의학회지
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• 제29권3호
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• pp.283-289
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• 1989

In order to measure in vitro cell mediated immunity in the guinea pigs sensitized with the killed bacilli of Mycobacterium bovis ($AN_5$), M avium (serotype 2), M tuberculosis and M intracellulare (serotype 8), leukocyte adherence inhibition (LAI) test was established using the antigens of purified protein derivatives (PPD) tuberculin. By using LAI test, specificity of cell-mediated immune responses of the guinea pigs inoculated with various Mycobacterium spp was investigated, and comparison between values of LAI and skin test was also made to evaluate the specificity of the newly designed test. The results obtained throughout the experiments were summarized as follows; 1. The optimal concentration of PPD antigens for LAI test was 1 to 2mg per ml of medium. 2. When the leukocytes of guinea pigs sensitized with both M bovis($AN_5$) and M avium (serotype 2) for 2 to 8 weeks were incubated with homologous or heterologous PPD antigens, mean values of LAI test were $61.2{\pm}11.2$ and $65.6{\pm}5.1%$ in homologous PPD antigens respectively, while $30.0{\pm}3.7$ and $32.8{\pm}5.7%$ in heteNlogous PPD antigens, showing the prominently high value of LAI in the homologous syst,em (p<0.01). 3. When the leukocytes of guinea pigs sensitized with both M tuberculosis and M intracellulare (serotype 8) for 2 to 8 weeks were incubated with homologous and heterologous PPD antigens, mean values of LAI test were $67.9{\pm}2.9$ and $66.9{\pm}5.0%$ in homologous PPD antigens, while $27.4{\pm}7.4$ and $24.4{\pm}7.1%$ in heterologous PPD antigens, showing the prominently high value of LAI in the homologous system (p<0.01). 4. Comparing with the specificity of LAI and skin tests on the basis of the value obtained from the homologous system, deviation of reaction was revealed to be 49.5 to 100.2 in LAI test, and -15.9 to 52.0 in skin test.

• 대한물리의학회지
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• 제7권1호
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• pp.77-85
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• 2012

Purpose : The purpose of this study was to investigate the effects of trunk exercises on the balancing ability of elderly Hansen's disease patients with lower extremity dysfunction. Method : A total of 24 elderly Hansen's disease patients were divided into two groups: 10 without lower extremity dysfunction and 14 with lower extremity dysfunction. The groups exercised for 60 minutes, two days a week, for a total 12 weeks; balancing ability was measured with the one leg standing test, tandem walking test, and timed up-and-go test. The patients were tested and their results were compared both before and after the completion of their exercise programs. Lower extremity dysfunction was assessed according to the following criteria: unilateral foot-drop, toe-loss, and below-knee amputation. Results : After the exercises, participants in both groups showed a positive, statistically significant difference in balance, compared with before the exercises (the one leg standing test, tandem walking test, and timed up-and-go test; p<.05). For comparison purposes, the group with dysfunction and the group without dysfunction were tested before and after the completion of their exercises. Before the exercises, there was a statistically significant difference in the one leg standing test, tandem walking test, and timed up-and-go test (p<.05). However, after the exercises, there was no significant difference in the one leg standing test, tandem walking test, and timed up-and-go test (p>.05). Conclusion : Ultimately, balancing ability was improved in both of the groups after trunk exercises were performed. Although balancing ability was improved, elements of lower extremity dysfunction remained, such as unilateral foot-drop, toe-loss, and below-knee amputation.

• 항공우주기술
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• 제8권1호
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• pp.1-9
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• 2009

스마트무인기는 수직이착륙과 고속비행이 동시에 가능하도록 헬리콥터와 고정익 항공기 의 장점을 결합한 틸트로터 항공기이다. 현재 지상통합시험을 수행중이며, 4자유도 지상치구시험과 안전줄 호버시험을 거쳐 비행시험을 수행할 예정이다. 스마트무인기에 적용된 제어법칙을 검증하기 위해서 40%축소기를 개발하여 비행시험을 수행하였다. 비행시험결과 예측하기 어려웠던 틸트로터 항공기의 고유한 기술적인 문제점들이 발생하였으며, 이러한 문제점을 해결하여 전자동 비행시험을 완료하였다. 본 논문에서는 국내 최초로 수행된 축소형 틸트로터 항공기의 비행시험 과정 중에 발생한 주요한 문제점을 서술하고, 그 해결과정을 상세하게 기술하였다. 축소형 틸트로터 항공기의 전자동 비행시험 수행을 통해 경험한 시행착오와 개선사항은 향후 계획된 스마트 무인기의 실물기 비행시험을 성공할 수 있는 훌륭한 초석이 될 것이다.

• 대한디지털의료영상학회논문지
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• 제13권4호
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• pp.177-183
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• 2011

This study intends to investigate patients' exact exposure doses by comparatively measuring ESD (Entrance Surface Dose) with the DAP meter, which excludes scattered rays, and ESD with the Xi multifunction meter, which includes scattered rays, by posture changes for Esophagography test and UGI test. The materialwere examined through Sonialvision-SafireII SPEC overtube system. ESD was measured by using the DAP meter, and as a tool to measure ESD including scattered rays on the plane of incidence of human phantom, the Xi multifunction meter was used. The average fluoroscopic time of Esophagography test was 4.192 minutes and the average number of images was 47.7, while the average fluoroscopic time of UGI test was 6.881 minutes and the average number of images was 37.8. The ratios of the incident dose of DAP meter and the ESD of Xi meter were calculated bydividing the fluoroscopic time and the number of images by each posture change. As for Esophagography test, the dose increased by 21.6~55.5% in the fluoroscopic test and by 4.8~24.7% in the spot test. In the front spot test, however, the does increased by as little as 5.3%. As for UGI test, the dose increased by 21.1~49.5% in the fluoroscopic test and by 10.1~34.9% in the spot test. It is expected that measuring doses in consideration of scattered rays by posture changes will be an important index in evaluating and managing patients' exact exposure doses for each test above. Furthermore, it is judged that this sort of study is inevitable and desirable to reduce patients' exposure doses after all.

• 문화기술의 융합
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• 제7권1호
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• pp.194-201
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• 2021

본 연구는 간호대학생을 대상으로 지각된 스트레스, 자아존중감, 전공만족도가 시험불안에 미치는 영향을 확인하여 시험불안을 조절하기 위한 기초자료를 제공하고자 시도되었다. 연구참여자는 B시의 간호대학생 251명을 대상으로 하였다. 자료분석은 SPSS 22.0 프로그램을 이용하여 실수, 백분율, 평균, 표준편차, t-test, ANOVA, 피어슨 상관계수, 다중회귀분석으로 분석하였다. 대상자의 시험불안은 2.97±.54점이었고, 일반적 특성에 따른 시험불안의 차이를 분석한 결과 성별(t=-3.241, p=.001), 대학생활만족도(F=5.682, p=.004)에서 유의한 차이를 나타냈다. 연구대상자의 시험불안은 지각된 스트레스(r=.361, p<.001)와는 정적상관관계, 자아존중감(r=-.186, p=.003)과는 부적상관관계를 나타냈다. 대상자의 시험불안에 영향을 미치는 요인은 지각된 스트레스, 성별로 나타났고, 설명력은 14%로 확인되었다. 본 연구결과를 통하여 간호대학생을 대상으로 시험불안에 영향을 미치는 요인을 확인함으로써 시험불안을 중재할 수 있는 기초자료로 활용할 수 있을 것이다.