http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 申玟圭 (검색결과 287 건)
- 무료
- 기관 내 무료
- 유료
-
액체 로켓 엔진 연소 불안정 모사를 위한 음향 가진 장치 설계 및 검증
신민규,오정화,차정열,노승환,고영성,김홍집 한국항공우주학회 2024 韓國航空宇宙學會誌 Vol.52 No.4
본 연구에서는 액체 로켓 연소기의 연소 불안정 모사를 위한 음향 가진 장치를 개발하였다. 1T 모드 모사를 위한 비원통형 연소기에 보조 노즐과 가진 장치가 구성되며, 가진 장치는 서보모터와 가진 휠로 구성된다. 제작된 가진장치는 상온 실험과 연소 실험을 통해 가진장치를 검증하였다. 상온 실험 결과 음향 공진 주파수는 이론값에 가깝게 구현되었으며, 동압 센서 위치에 따라 각 모드에 상응하는 위상 차이를 확인할 수 있었다. 또한 1T 모드에서 연소실 압력의 5% 이상을 교란할 수 있음을 확인하였다. 연소 실험에서는 연소 가스의 음속 변화로 인하여 1T 모드가 아닌 1T1L 모드를 모사하였지만, 가진 장치의 교란 성능은 검증이 되었다. 이를 통해 연소 불안정 모사에 사용되는 가진장치 검증 시험을 성공적으로 수행하였다. In this study, an acoustic excitation device was developed to simulate the combustion instability of a liquid rocket combustor. A non-cylindrical combustor for 1T mode simulation was composed of an auxiliary nozzle and excitation device, and the excitation device consisted of a servo motor and excitation wheel. The designed excitation device was verified through cold test and combustion test. As a result of the cold test, the acoustic resonance frequency was observed to be close to the theoretical value. Additionally, the phase difference corresponding to each mode could be confirmed according to the position of the dynamic pressure sensor. It was also confirmed that more than 5% of the combustion chamber pressure can be disturbed in the 1T mode. During the combustion test, changes in the sonic velocity of combustion gas led to the simulation of the 1T1L mode instead of the 1T mode. Despite this, the excitation device's disturbance performance was successfully verified. The verification test of the excitation device used for combustion instability simulation was successfully performed.
-
-
-
-
-
벤질 알코올 후처리를 통한 고성능 역삼투 분리막 제조공정
신민규,전성권,이정현 한국막학회 2018 한국막학회 총회 및 학술발표회 Vol.2018 No.11
Recently, many efforts to enhance separation performance of the reverse osmosis (RO) membranes have been made. Among them, the post treatment with organic solvent, so called solvent activation, has been recognized as an effective method to improve membrane performance. However, solvent activation enhances water flux along with the loss of NaCl rejection. Furthermore, there have been no clear mechanisms and reliable criteria of the solvent activation effects. In this study, we demonstrate that a new type of organic solvent, benzyl alcohol, can effectively activate the RO membrane to significantly enhance water permeation without deteriorating NaCl. Based on this results, we elucidate the underlying solvent activation mechanism and propose a reliable indicator of the solvent activation effect.
-
-
-
증식당뇨망막병증환자에서 유리체절제술 전 유리체강내 베바시주맙 주입의 효과
신민규,김나미,이지은,엄부섭 대한안과학회 2009 대한안과학회지 Vol.50 No.5
Purpose: The effect of preoperative intravitreal bevacizumab (AvastinⓇ) injection was investigated in primary vitrectomy forsevere proliferative diabetic retinopathy. Methods: Eyes that underwent vitectomy for proliferative diabetic retinopathy were followed up at least 6 months and werereviewed retrospectively. The authors reviewed functional outcomes, complications, and operation time between preoperativebevacizumab injection (group I) and non-injection groups(group II). Results: Among 93 eyes of 87 patients, the injection group consisted of 44 eyes of 41 patients and the non-injection gauge groupconsisted of 49 eyes of 46 patients. The mean interval between injection and vitrectomy was 5.8 days. Final visual acuitysignificantly improved as compared to preoperative visual acuity, and group I showed better visual acuity than group II (p=0.008). Visual acuity improved logMAR 0.2 or more in 36 eyes in group I and 43 eyes in group II (p=0.167). The average duration ofpostoperative vitreous hemorrhage was 1.02 days in group I, and 4.02 days in group II (p=0.2.08). Recurrence of vitreoushemorrhage was not observed in group I or in 2 eyes of group II (p=0.274). Epiretinal membrane occurred in 2 eyes of group I,and in 9 eyes of group II (p=0.031). Only a single eye in group I had neovascular glaucoma after vitrectomy (p=0.527). The operationtime of group I was 64.8 minutes, which was significantly shorter than 78.1 minutes of group II (p=0.018). Conclusions: Intravitreal bevacizumab injection before vitrectomy in proliferative diabetic retinopathy facilitated removal of thefibrovascular membrane, and leads to less postoperative complications and better functional outcomes. Intravitreal bevacizumabinjection before vitrectomy can be considered as an effective preoperative adjuvant. 목적: 증식당뇨망막병증에서 술 전 유리체강 속 bevacizumab (AvastinⓇ) 주입의 효과를 알아보았다. 대상과 방법: 증식당뇨망막병증으로 유리체절제술 후 6개월 이상 경과 관찰이 가능했던 환자를 대상으로 술 전 bevacizumab 주입군(Ⅰ군)과 미주입군(Ⅱ군)으로 나누어 시력, 합병증 및 수술시간을 비교하였다. 결과: 총 93눈(87명) 중, Ⅰ군 44눈(41명), Ⅱ군 49눈(46명)이었다. Bevacizumab은 술 전 평균 5.8일째 주사하였으며, 최종시력은 양군모두 유의하게 상승하였고, 술 후 6개월째 Ⅰ군의 시력이 유의하게 좋았다(p=0.008). Ⅰ군 36눈, Ⅱ군 43눈에서 logMAR 0.2 이상의유의한 시력상승을 보였다(p=0.167). 술 후 유리체출혈 평균 잔존기간은 Ⅰ군 1.02일, Ⅱ군 4.02일 이었다(p=0.208). 술 후 새로운 유리체출혈은 Ⅰ군은 없었고, Ⅱ군에 2눈, 망막앞막은 Ⅰ군 2눈, Ⅱ군 9눈, 신생혈관녹내장은Ⅰ군은 없었고, Ⅱ군에 1눈에서 생겼다(p=0.274,0.031, 0.527). 수술시간은 평균 64.8분, 78.1분으로 Ⅰ군이 짧았다(p=0.018). 결론: 증식당뇨망막병증환자의 수술 전 유리체강 속 bevacizumab 주사는 수술 중 증식막을 용이하게 제거할 수 있도록 하며 술 후합병증을 줄여 더 나은 시력을 얻을 수 있게 하였다. 그러므로 전처치로 유용할 것으로 사료된다.
-
굴절교정레이저각막절제술 10년 후 각막조직의 공초점현미경 소견
신민규,구기홍,이종수,Min Kyu Shin,Gi Hong Koo,Jong Soo Lee 대한안과학회 2009 대한안과학회지 Vol.50 No.2
Purpose: The present study compares, using a new generation high‐resolution in vivo confocal microscope, the corneas of patients who underwent photorefractive keratectomy (PRK) 10 years previously with those of healthy persons. Case Summary: A confocal microscope (Confoscan 4.0, Fortune Technology, Italy) was used to get the data from healthy volunteers and patients. Corneal cross‐sectional images of the epithelium, Bowman's layer, stromal layer (anterior, middle and posterior keratocyte), Descemet's membrane, and endothelium were compared. In PRK corneas, the superficial epithelium was nearly intact and the subbasal nerve plexus was visible, but some hyperreflective areas were also found in the nerve plexus. Because of the absence of the Bowman's layer, some ECM and keratocytes were visualized in their optical section. Although anterior keratocytes showed uneven distribution with less cellularity, middle and posterior keratocytes looked unaffected. Likewise, there were no differences in the endothelium between the two groups. Conclusions: Ten years after PRK, the subbasal nerve plexus and anterior keratocytes showed histologic changes after corneal wound recovery.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
