• 항공우주시스템공학회지
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• 제17권6호
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• pp.144-148
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• 2023

항공기 배터리는 항공기의 엔진 시동 전원 및 비상 전원을 공급하는 역할을 하는 핵심 장비이다. 배터리는 안정적인 전원 공급을 위해 언제나 충분한 용량을 보장하도록 충전되어야 하며 높은 신뢰성을 유지해야 한다. T-50 계열 항공기 배터리는 -18 ℃ 이상의 낮은 온도에서 엔진을 최대 2회 시동할 수 있도록 설계하였으나, 겨울철에 엔진 시동에 실패하는 현상이 간헐적으로 발생하였다. 이에 본 논문에서는 배터리의 저온 충전 시 발생하는 실패 현상에 대하여 분석 및 시험을 수행하고 이를 바탕으로 충전 알고리즘을 개선하였다. 또한 저온시동 모사시험을 수행한 결과 저온에서의 배터리 충전 결함이 해결되었으며 충전 성능 향상이 확인되어 새로운 알고리즘의 개선을 확인하였다.

• 한국농공학회지
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• 제17권4호
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• pp.3931-3942
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• 1975

This study was conducted to investigate the strength of soil cement for varied curing temperatures (0,10,20,30,40,50,60$^{\circ}C$) and cement content (3,6,9,12%) in four cement-stabilized soils (KY: sand, MH: sand, SS: sandy loam, JJ:loam). The experimental results obtained from unconfined compressive strength tests were as follows: 1. According to increase of curing temperature as 30,40,50, and 60$^{\circ}C$, the unconfiened compressive strength of soil cement increased, the rate of increase in the early curing period was large, and around 120 hours was suifficient curing time to complete hardening. 2. The strength at 10$^{\circ}C$ decreased to the rate of 30 to 40 percent than that of 20$^{\circ}C$ while the strength at 0$^{\circ}C$ was very small, strength of soil cement increased in cold weather unless that the temperature was below 0$^{\circ}C$ 3. The average maximum temperature, about 30$^{\circ}C$ during July and August in Korea may be recommended for a optimum construction period to increase the strength of soil cement. 4. Accelerated curing time that strength was equivalent to 28-Day norma1 curing decreased in accordance with the increase of curing temperature, and also accelerated curing decreased the effect of cement content. Accelerated curing that strength was equivalent to 28-day normal curing for soil cement of cement content 9% and temperature 60$^{\circ}C$ was 45 hours; KY, 50 hours: MH, 40 hours; SS, 34 hours; JJ. 5. According to the increase of the percent passing of No. 200 sieve, accelerated curing times became shorter to become the required stength. 6. Relation between accelerated curing times and normal curing days was showeda linear of which slope decreased in accordance with the increase of curing temperature, it may be expressed as follows: (1). 30$^{\circ}C$ t=3.6d+6(r=0.97) (2). 40$^{\circ}C$ t=3.2d-5.1(r=0.95) (3). 50$^{\circ}C$ t=2.1d-4.0(r=0.93) (4). 60$^{\circ}C$ t=1.4d+4.0(r=0.90) in which t=accelerate curing time. d=normal curing day. 7. Accelerated curing time that the strength was equivalent to 35kg/$\textrm{cm}^2$ which was the strength of cement brick was 96 hours at temperature 30$^{\circ}C$ to SS 9%, and 120 hours at temperature 50$^{\circ}C$ to JJ 9%, Consequently, a economic soil cement brick may be made in future.

• 한국가금학회지
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• 제41권2호
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• pp.77-85
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• 2014

본 연구는 소시지 제조 시 오리고기와 돼지고기의 혼합비율에 따른 냉장 저장 중 품질 특성을 구명하고자 수행하였다. 처리구는 소시지 제조 시 사용되는 고기 함량을 기준으로 오리고기 100%(T1), 돼지고기 100%(T2), 오리고기 50% + 돼지고기 50%(T3), 오리고기 40% + 돼지고기 60%(T4) 및 오리고기 30% + 돼지고기 70%(T5)로 나누었다. 그 결과, 수분은 다른 처리구에 비해 T1이 유의적으로(p<0.05) 가장 높았고, T2가 유의적으로(p<0.05) 가장 낮게 나타났다. 단백질과 지방함량에 있어서는 T2가 다른 처리구에 비해 유의적으로(p<0.05) 가장 높게 나타났다. 명도의 경우, T1이 전 저장기간 동안 다른 처리구에 비해 유의적으로(p<0.05) 가장 낮은 명도를 보였다. 적색도는 다른 처리구에 비해 T1이 전 저장기간 동안 유의적으로(p<0.05) 가장 높게 나타난 반면, T2는 전 저장기간 동안 유의적으로(p<0.05) 가장 낮은 것으로 나타났다. 경도의 경우, 오리고기 40%와 돼지고기 60%로 제조한 T4가 다른 처리구에 비해 전 저장기간 동안 유의적으로(p<0.05) 높게 나타났다. 응집성의 경우, 냉장 저장 2주까지 T5가 다른 처리구에 비해 유의적으로(p<0.05) 높게 나타났다. 관능평가 결과, 육향, 맛 및 조직감에 있어서는 T5가 유의적으로(p<0.05) 낮은 것으로 나타난 반면, 다른 처리구 간에는 유의적인 차이가 없는 것으로 나타났다. 전체적인 기호도는 T5가 다른 처리구에 비해 유의적으로(p<0.05) 낮은 것으로 나타났다. 이상의 결과를 종합해 볼 때, 오리고기 소시지 제조 시 경도와 기호성을 좋게 하기 위한 근육 단백질의 혼합 비율은 오리고기 40%와 돼지고기 60%의 비율이 적당한 수준인 것으로 사료된다.

• 치위생과학회지
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• 제7권1호
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• pp.31-35
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• 2007

Caesalpinia sappan L. (Leguminosae) is an oriental medicinal herb distributed in China and Taiwan, and its heartwood has been traditionally used as an analgesic, a therapy for thrombosis or tumor. This study was to investigate the proliferation and inhibition effects of Caesalpinia sappan extracts against human epithelial cell and cancer cell lines. The methanol extract of dried C. sappan heartwood was evaporated (KS-6), and then sequentially extracted by hexane (KS-01), chloroform (KS-02), ethyl acetate (KS-03), n-butanol (KS-04), and water (KS-05). After 48 hr of exposure, these fractions at a concentration of $50{\mu}g/ml$ significantly increased, and reduced cell proliferation in both human normal epithelial and cancer cell lines. The ethyl acetate fraction (KS-03) among organic solvent fractions was 120.2% of the most proliferation activity ($50{\mu}g/ml$) against HaCaT human epithelial cell. However, fractions from chloroform, butanolic and methanolic extract had 7.2, 28.7 and 20.8% of antiproliferative effect on HaCaT cell, respectively. In cell proliferation effects of C. sappan extract on HeLa, SiHa and C33A human cervical cancer cells, chloroform fraction (KS-2) was the most antiproliferative activity, its antiproliferative rate (dosage, $50{\mu}g/ml$) relative to control was 25.8, 12.2 and 17.4% for SiHa, HeLa and C33A, respectively. The results indicated that the six extract fractions could induce cell cycle stimulate or arrest in some way. Finally, further investigation is needed to assess the molecular mechanisms mediated anticancer activities of this plant.

• The Journal of Korean Physical Therapy
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• 제25권4호
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• pp.224-231
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• 2013

Purpose: The purpose of this case study was to investigate three poor fibrinolytic responders with chronic ischemic stroke to acute exercise intensity and time. Methods: Three ischemic stroke patients (male) from the stroke center located at Busan metropolitan area in Republic of Korea volunteered at this study. They performed two single session exercises that were a VO2peak test and a single bout treadmill walking (70-75%HRpeak, 30 min, 50min). Fasting blood samples for determination of tissue Plasminogen Activator (tPA) and Plasminogen Activator Inhibitor-1 (PAI-1) were obtained before, immediately after, 30min after acute exercise. SPSS 12.0 was used for analyzing of data and computing mean and standard deviation, and change rate was conducted between times. Results: In fibrinolytic activity according to the intensity and time of acute exercise, tPA change increased steadily during the recovery stage after the VO2peak in the cases, but PAI-1 activity showed different patterns among the cases. In a single bout treadmill walking (70-75%HRpeak, 30 min, 50min), tPA change increased between 30min and 50min. Conclusion: In conclusion, these results suggest that the exercise prescription for poor fibrinolytic responder with three male chronic ischemic stroke patients without motor disability recommend at 70-75%HRpeak, over 30min.

• Journal of Astronomy and Space Sciences
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• 제3권1호
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• pp.53-66
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• 1986

Isophotes and surface brightness distribution were obtained for the late type normal spiral galaxy NGC 7793 (morphological type SA(s)d) which is one of the Sculptor group. The calculated total luminosity $M_{T}$ is obtained as 9.44 and the corrected face on magnitude ${B_T}^{circ}$ is 9.10. The revised distance to this galaxy $\Delta$=3.1 Mpc (de Vaucouleurs and Davoust 1980) is used for calculating the absolute magnitude ${M_T}^{circ}$ = -18.36. From the isophotes, the position angle to the major axis is $101^{circ}$, the mean axial ratio is q=b/a =0.65, and the inclination is i=50$^{circ}$. The concentric indices $C_{21}$=1069 and $C_{32}$ =1.50 are well agreed to the average value of Sd type galaxies.

• Applied Biological Chemistry
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• 제47권2호
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• pp.202-207
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• 2004

어성초 분말을 포함하는 차가버섯 발효 조성물의 물 추출물이 인체 위암 세포 AGS 및 대장암 세포 HCT-15, 그리고 정상세포 NIH3T3 fibroblast의 세포 생육에 미치는 영향을 검토하였다. 세포독성 실험은 세포수 count와 MTT 방법으로 측정하였다. 어성초 분말을 포함하는 차가버섯 발효 조성물의 제조는 차가버섯과 어성초 분말을 혼합하고, 여기에 대두 발효 미생물원을 다시 혼합시켜 습도 $50{\sim}60%$,온도 $30{\sim}37^{\circ}C$에서 30일 정도 발효시킨 후 건조 시킨 분말에서 5% 물 추출물을 얻어 동결건조 시켜 실험에 제공하였다. MTT assay 방법에서 차가버섯 발효 조성물의 수용성 추출물 0.16, 0.4, 0.8, 1.6 및 4.0 mg/ml 첨가 농도에서 AGS 세포 생육은 13, 25, 40, 67 및78% 억제 되었으며, HCT-15세포 생육은 22, 40, 50, 69및 76%씩 각각 억제되었다. 그러나 동일한 실험조건에서 정상 세포수 NIH3T3은 86% 이상의 생존율을 나타내었다. 차가버섯 발효 조성물의 수용성 추출물은 인체 대장암 세포주 HCT-15와 위암 세포수 AGS에 대해 생육억제 작용이 강한 반면, 정상세포 NIH3T3에 대해서는 세포 독성을 거의 나타내지 않아 가장 바람직한 암예방 또는 항암식품 개발가능성을 제시하였다.

• 대한본초학회지
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• 제22권4호
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• pp.35-43
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• 2007

Objective : The aim was to study experimentally the effects of Daeyoungjeon(DYJ) on the hypothyroidism of rats induced by thiouracil. Methods : Spargue-Dawley rats were separated into four groups. Except normal group, the other three groups were treated with thiouracil 0.50g/kg/days for 30 days by oral administration. Among the three groups, one group was treated DYJ extract 0.75g/kg/days for 20 days separately. Another group was treated DYJ extract 1.50g/kg/days for 20 days separately. T3-uptake, T3, T4, TSH, hematological values, enzyme activity, total cholesterol, triglyceride and Na+ content change in the Serum of rats were measured after medication of solid extract of DYJ. Results : As a result of this study, in the serum T3-Uptake and T4 level, hematological values and sodium were increased in DYJ group compared to control group. The serum TSH, total cholesterol, triglyceride, enzyme activity and body weight were decreased in DYJ group compared to control group. Conclusion : According to the above results, it is suggested that DYJ is effective to cure hypothyroidism.

• 대한의생명과학회지
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• 제10권3호
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• pp.263-268
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• 2004

This study was carried out to evaluate the cytotoxic effect of phenolic compound on normal NIH 3T3 fibrolasts. The colorimetric assay for phenol compound, syringic acid was performed by MTT assay or XTT assay. MTT or XTT assays are known as a very sensitive method in measuring the cytotoxic effect of chemical agents in vitro. In the present study, syringic acid on normal Nlli 3T3 fibroblasts did not show any cytotoxicity for MTT assay or XTT assay compared with control after cells were treated with various concentrations of syringic acid for 48 hours. MTT/sub 50/ and XTT/sub 50/ were 3,340.9 μM and 2,462.4 μM of syringic acid, respectively. From the above the results, it is suggested that phenolic compound of syringic acid did not have any cytotoxicity on normal NIH 3T3 fibroblasts.

• 한국시뮬레이션학회논문지
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• 제32권4호
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• pp.27-39
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• 2023

본 연구는 간호대학생을 대상으로 학생주도 팀기반 문제중심학습 시뮬레이션 (SSTPBL) 수업을 개발하고 그 효과를 검증하기 위한 혼합연구이다. 자료수집은 2022년 9월 15일부터 2022년 10월 20일까지 A시 소재 일개 대학 간호학과 4학년 학생 51명에게 설문조사 및 4명을 대상으로 포커스 그룹 인터뷰를 진행하였다. 수집된 자료는 SPSS version 25.0과 주제분석을 활용하여 분석하였다. 양적연구 결과, 시뮬레이션 경험 만족도(t = 3.51, p < .01), vSim 경험 만족도(t = 3.50, p < .01), 예비 간호사로서의 준비 정도(t = 3.73, p < .01), 학습 자기효능감(t = 3.87, p < .01), 협력적 자기효능감(t = 4.30, p < .01), 문제해결 능력(t = 5.26, p < .01), 교육 만족도(t = 3.54, p < .01), 디지털 헬스 형평성(t = 2.18, p < .05)을 향상시키는 데 효과가 있었다. 질적연구에서 도출된 6개 주제는 '임상실습과 유사함', '몰입에 어려움', '타인을 통해 배워감', '자기반성을 통한 배움', '새로운 경험을 통한 자신감 향상', '새로운 수업방식'이었다. 본 연구결과를 바탕으로 팬데믹 이후 임상실습 제한이 커지고 있는 상황에서 학생주도 팀기반 문제중심학습 시뮬레이션 (SSTPBL) 수업이 예비간호사들의 새로운 훈련 방법으로 다양하게 활용될 수 있을 것으로 기대한다.