• Title/Summary/Keyword: descending

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교반 유무에 따른 수모델을 사용한 액적의 하강 속도에 대한 액적 크기 및 오일 점도의 영향 (Influence of Droplet Size and Oil Viscosity on the Descending Velocity of Droplets Using Water Model With and Without Stirring)

  • 권혁인;;정성용;김선중
    • 자원리싸이클링
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    • 제32권2호
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    • pp.33-42
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    • 2023
  • 금속 에멀젼(metal emulsion)은 제강 공정의 효율성을 높이는 방법으로 수십 년 동안 연구되어 왔습니다. 본 연구는 육안으로 관찰하기 어려운 고온 실험의 단점을 보완하기 위해 상온에서 관찰 가능한 수모델을 이용하여 수행하였다. 슬래그 내 금속 에멀젼의 대신하여 증류수를 실리콘 오일에 적하하여 운동량 균형 방정식에 의한 계산 결과와 비교하는 실험을 하였다. 물방울의 하강 속도는 물방울의 직경과 유체(실리콘 오일)의 점도가 증가함에 따라 감소하였다. 교반 조건에서 실리콘 오일에서 물방울의 하강 속도를 시뮬레이션하기 위해 유체(실리콘 오일)의 유속을 입자 이미지 속도계(PIV) 방법으로 측정하였다. 물방울의 하강 속도 계산은 점성 실리콘 오일을 교반하거나 교반하지 않고 측정된 값과 잘 일치하였다.

외상성 흉부대동맥류치험 1례 보 (Traumatic aneurysm of descending thoracic aorta: report of one case)

  • 안혁;장병철;임승평
    • Journal of Chest Surgery
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    • 제17권1호
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    • pp.67-73
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    • 1984
  • A 25 years old male patient with traumatic aneurysm of descending thoracic aorta was treated successfully. He was admitted due to blunt trauma to the chest wall as falling down into water. He has been treated with closed thoracotomy and close observation. After a month simple chest film showed abnormal mass shadow around the aortic knob. Aortogram revealed aneurysm of descending thoracic aorta. Aneurysm was resected and replaced with woven Dacron graft with aid of Gotts shunt. His postoperative course was uneventful.

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우측 하행 대동맥을 동반한 중복 대동맥궁 - 1례 수술 치험 - (Double Aortic Arch with Right Sided Descending Aorta - Report of 1 case -)

  • 조경수
    • Journal of Chest Surgery
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    • 제23권1호
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    • pp.201-204
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    • 1990
  • The double aortic arch is the commonest anomaly among the vascular rings are relatively rare congenital vascular anomalies. This anomaly is malformation of the aortic arch system may, by compression of the trachea and esophagus, cause respiratory distress and dysphagia. We experienced one case of double aortic arch with right sided descending aorta with predominant right anterior arch treated surgically at Kyung Hee University Medical Center. 1-year-old male patient with acute airway obstruction due to combination of double aortic arch and right descending aorta. The diagnosis was made by simple X-ray & confirmed by barium esophagogram & aortogram. The operative approach was through left thoracotomy & underwent division of the left aortic arch & division of ligamentum arteriosum & suspension of divided proximal end of anterior arch to anterior thoracic wall. The postoperative courses was uneventful and doing well on the 3 years.

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하행흉부대동맥류(下行胸部大動脈瘤) 치험(治驗) 1례(例) (Aneurysm of the Descending Thoracic Aorta -Report of a Case-)

  • 이동준;김상형
    • Journal of Chest Surgery
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    • 제9권1호
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    • pp.44-49
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    • 1976
  • Aneurysm of the Aorta is a grave disease mostly producing disabling symptoms and ultimate death by rupture and hemorrhage without surgical intervention. The author recently experienced one case of surgical correction of descending thoracic aortic aneurysm treated with excision of the aneurysm and replacement of Dacron artificial vessel under temporary external by pass technique in November, 10th, 1975. 9mm internal diameter arterial cannula was inserted into upper and below the aneurysm. Bypass time was about 1 hour. The case was 35 years old women who had small egg sized saccular aneurysm in the upper third of the descending thoracic aorta involving the 1t. subclavian artery. Histopathological diagnosis was arteriosclerotic. Immediate postoperative course had been uneventful except low pressure and pulse of the left arm. The follow-up was possible up to date about 3 months. The patient has been doing well with ordinary activities except mild left chest discomfort.

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하행결장에 발생한 Hirschsprung씨 병의 Pull-through수술 경험 (Surgical Experience with Pull-through Operation in Hirschsprung's Disease of the Descending Colon)

  • 홍정
    • Advances in pediatric surgery
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    • 제10권1호
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    • pp.60-62
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    • 2004
  • Leveling colostomy with a frozen-section biopsy in a Hirschsprung's disease is an important factor for a successful procedure. Two neonatal cases of Hirschsprung's disease in the descending colon are reported. In both cases, loop ileostomy was established because of the unavailability of frozen-section biopsy on an emergency basis. At the time of definitive procedure of the first case, transition zone at the splenic flexure was noted and was compatible with the frozen section biopsy. In the second case, an unexpected longer resection at a higher level than transition zone was required because of the poor vascularity after dissection. In conclusion, a leveling colostomy should be selected as a choice in long-segment Hirschsprung's disease. Confirming preservation of the marginal artery of Drummond is particularly important in case of Hirschsprung's disease in the descending colon.

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신생아에서 심실중격결손증을 동반한 대동맥궁 결손증의 일단계 완전 교정술 -3례 치험- (One Stage Eepair of Interruption of Aortic Arch with VSD in Neonate)

  • 전희재
    • Journal of Chest Surgery
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    • 제28권6호
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    • pp.610-618
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    • 1995
  • Three neonates with interrupted aortic arch with VSD underwent one stage repair using revised technique of cardiopulmonary bypass with short period of circulatory arrest. A left posterolateral thoracotomy was made to permit mobilization of the descending aorta and placement of polytetrafluoroethylene[PTFE graft for distal aortic perfusion. Then the patient was placed in the supine position and a median sternotomy was performed to permit the proximal dissection, VSD repair, and direct anastomosis between the ascending aorta and descending aorta. This technique has advantages to facilitate direct anastomosis between the ascending aorta and the descending aorta, to lessen circulatory arrest time, and to prevent dangerous laceration and post-operative narrowing of the thin small ascending aorta at cannulation site. There was no operative mortality but postoperative stenosis developed in one case which was relieved with balloon aortoplasty.

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Tuberculous Aortitis Complicated with Pseudoaneurysm Formation in the Descending Thoracic Aorta: A Case Report

  • Seo, Dong Ju;Kim, Joon Bum
    • Journal of Chest Surgery
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    • 제45권6호
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    • pp.408-411
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    • 2012
  • A 51-year-old male with sustained fever was diagnosed with military tuberculosis and tuberculous aortitis complicated with pseudoaneurysm formation at the proximal descending aorta. A follow-up computed tomography evaluation showed an increased size of the pseudoaneurysm in this area, suggestive of a contained rupture. Consequently, the patient underwent emergency excision and replacement of the aorta using a left heart bypass. The patient was discharged without postoperative complications on post-operative day 12. During the one-year follow-up period, the patient was free of any complications or recurrence of tuberculosis. We report a case of pseudoaneurysm of the descending aorta that was successfully surgically repaired.

상행 대동맥과 하행 흉부 대동맥에 동시에 발생한 가성 대동맥류 치험 1례 (Pseudoaneurysm Involving Proximal Ascending Aorta and Proximal Descending Thoracic Aorta)

  • 이호철;류한영
    • Journal of Chest Surgery
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    • 제29권3호
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    • pp.337-341
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    • 1996
  • A 40-year-old male patient who had ascending aortic pseudoaneurysm Involving right coronary artery obstruction and thoracic descending aortic pseudoaneurysm was successfully managed by two-stage operation. Repair of intimal tear of ascending aortic pseudoaneurysm with a patch of woven dacron vascular graft and right coronary artery bypass graft with great saphenous vein were performed in first stage operation. On 28 days postoperatively, Repair of intimal tear of descending aortic pseudoaneurysm with a patch of woven dacron vascular graft was done under the femorofemoral partial cardiopulri!onary bypass in second stage operation. The patient was discharged at postoperative 13th days without any evident.

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황제내경(黃帝內經)이 동원(東垣)의 의학사상(醫學思想)에 미친 영향에 관한 연구 (A Study on the Effect of Naegyeong on Lee Dong-yuan's Medical Thought)

  • 남무길;정창현
    • 대한한의학원전학회지
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    • 제18권2호통권29호
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    • pp.85-101
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    • 2005
  • The purpose of this study is to explain the effect of Naegyeong on Lee Dong-yuan's medical thought. Lee is famous physician who studied the theory of spleen and stomach. His general idea of spleen and stomach could be thought as an result of study on Naegyeong. He distinguished between Eum disease and Yang disease and classified into internal injury and external affection. In the contents of Naegyeong, he took note of the four seasons' changes that are continued by the ascending and descending between heaven and earth, also he took note of the fact that movement of human body's organs is represent of ascending and descending. Human body is a site that a singular ascending and descending of Gi of the stomach.

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웨이브렛 변환과 Descending Epsilon 학습방법을 이용한 시계열 예측 (Implement of Time Series Forcasting System Using the Wavelet Transform and Descending Epsilon Learning Method)

  • 윤나미;정유정;이기준;정채영
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2000년도 추계학술발표논문집 (하)
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    • pp.1425-1428
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    • 2000
  • 본 논문에서는 빠르고 정확하게 기후를 예측, 분석하기 위해 웨이브렛 변환을 통해 Data의 특징을 추출하고 이를 신경망의 입력값으로 사용하는 기상예측시스템은 제안하였다. 또한 학습이 잘되지 않는 패턴에 대한 집중적인 학습을 수행할 수 있는 Epsilon Descending 학습방법을 사용하여 정확도를 상승시켰다. 예측실험결과 웨이브렛 변환을 데이터의 전처리 과정에 삽입한 제안 기상예측시스템이 기존의 신경망만을 통한 기상예측시스템에 비해 예측능력면에서 훨씬 더 우수함을 보였다.

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