• Journal of the Korean Institute of Gas
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• v.21 no.3
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• pp.1-8
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• 2017

The purpose of this study is to suggest the rupture disk design(size) and application at the two phase(gas-liquid) flow by runaway reaction at batch reactor. The definition of runaway reaction is abnormally exothermic reaction by the uncontrolled cooling water or deviated operating condition. As a result, the temperature of reactor is rapidly increasing. The causes of runaway reaction are either self-heating reaction or sleeper reaction. General methods of rupture disk size or safety valve are not suitable in the runaway reaction, because of temperature and pressure increasing rapidly in the reactor and the phases of relieving fluid is 2-phase flow. This study case of the reactor incident, the depressurization system such as safety valve and vent installed, however, the system did not relieved the pressure of reactor suitably. The orifice size of the safety valve were designed too small because the size had not been considered the phenomena and character of reaction. The batch reactor design should be considered by referring to the possibility of runaway reaction proposed in this study and the size of rupture disk design method considering 2-phase flow.

• Journal of Chest Surgery
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• v.36 no.1
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• pp.51-54
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• 2003

This patient was an 53-year-old man who had undergone Sengstaken-Blackmore tube insertion for esophageal varix bleeding. Two days after Sengstaken-Blackmore tube insertion, he developed severe left hemothorax and was transferred to our hospital. The esophagoscopic findings revealed a large perforation lengthening 8-cm in the intrathoracic esophagus. A left thoracotomy was performed 33 days after the injury due to repeated varix bleedings and poor conditions. An 8-cm longitudinal perforation of the intrathoracic esophagus with gross suppurative empyema was found. Primary repair and esophageal exclusion was performed 2cm proximal and distal to the perforation, using rows of nonabsorbable staplers(TA stapler 60 $\times$ 4.8) and large bore thoracostomy tubes were placed for local drainage. Six days after intrathoracic esophageal exclusion, an esophagogram revealed a leakage at just above the proximal stapling site. A cervical esophageal exclusion was performed using the same method. One hundred thirty seven days after exclusion operation for the intra-thoracic esophageal perforation, the patient was able to eat per orally without any secondary esophageal reconstructive surgery.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.2 no.2
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• pp.53-61
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• 2009

Purpose: This study was designed to evaluate the clinical usefulness of serial ultrasonography (USG) after arthroscopic rotator cuff repair and to assess the re-tear rate and the re-tear time according to the tear sizes and the repair method. Materials and Methods: Between January 2008 and June 2008, 52 patients were treated with arthroscopic rotator cuff repair, Of the 52 patients, 29 patients that had undergone more than six months follow-up underwent preoperative USG examinations and subsequent arthroscopic examinations. MRI and USG findings were compared with intraoperative results of arthroscopic examinations. The postoperative integrity of the rotator cuff was observed using serial USG examination performed postoperatively at two weeks, six weeks, three months, and six months. Results: Small to medium rotator cuff tear were identified in 10 patients where the double pulley suture bridge (DPSB) technique was performed; the re-tear rate was 20%. For 19 patients with large to massive rotator cuff tears, the re-tear rates was 100% for six patients who had undergone tendon to tendon (TT) repair, the re-tear rate was 50% for two patients who had undergone tendon to tendon and bone to tendon (TTBT) repair and the re-tear rate was 55% for11 patients where the DPSB technique was performed. Re-tear rates according to follow-up periods were 7% from two to six weeks, 66% from six weeks to three months and 27% from three to six months postoperatively. Conclusion: Serial USG examinations after arthroscopic rotator cuff repair were useful to assess the re-tear rate and the re-tear time. In addition, USG examination were useful for treatment planning during postoperative rehabilitation.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.1-5
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• 1998

Rotator cuff disease is the most common cause of shoulder pain. Recent understanding of structure and mechanics enables scientific approach to the treatment of the cuff teat. It is an integral component in the normal movement and function of the shoulder. This article addresses current knowledge of the structure and biomechanics of the rotator cuff, and reviews various kind of operative treatment.

• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.5-16
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• 1969

A design of new burst cartridge detection system for gas-cooled power reactor using a spherical sampling chamber with negative electrode is presented. The results of theoretical calculation indicate that the designed system is feasible for a practical application and sensitive enough to detect a 1 $\textrm{cm}^2$ hole in the fuel clad-ding.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.99-108
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• 2012

Purpose: To evaluate the clinical results of arthroscopic repair with UU-Tension Band suture for full thickness rotator cuff tear above 4 cm sized. Materials and Methods: From January 2006 to October 2011, in 71 full thickness tears above 4 cm sized which is possible to arthroscopic repair to medial margin of greater tuberosity. The group I is 71 patients which is arthroscopic repair with UU-Tension Band suture, and the group II is 20 cases which is arthroscopic repair with simple suture. Both groups were compared with a VAS score for pain, Activity of Daily Living, UCLA score, KSS score in pre operation, 7 months, 1 year and last follow-up. Statistical analysis was performed by student t test and paired t est. Mean age was 63.2 (52~80) year old, mean follow-up was 38.4 (13~62) months. Results: The VAS scores for pain decreased from 8.1 at preoperative period to 1.6 at postoperative last follow-up period in group I (p<0.05), the score decreased from 7.6 at preoperative period to 1.8 postoperative last follow-up period in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). Mean ADL scores increased from 12.5 at preoperative period to 29.0 post operative last follow-up period in group I (p<0.05), the score increased from 11.3 in pre op to 27.5 post-operative last follow-up in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). The UCLA score increased from 12.9 at preoperative period to 28.7 postoperative last follow-up period in group I (p<0.05), the score increased from 13.8 at preoperative period to 30.1 postoperative last follow-up period in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). In comparing of retear which was checked by MRI and ultrasound evaluated at postoperative period 7 months (mean: 27.5 weeks), the retears were 28% in the group I, and 11 shoulders out of 20 shoulders in the group II. The significant differences were noted between two groups (p<0.05). Conclusion: Arthroscopic repair with UU-Tension Band suture and simple suture for full thickness rotator cuff tear above 4 cm sized were not different clinical result between both groups. However, the significant differences were noted in point of failure rate between both groups.

• Journal of the Korean Arthroscopy Society
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• v.13 no.2
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• pp.119-125
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• 2009

The primary purposes of revision repair for a failed rotator cuff repair are a relief of pain and functional improvement. Therefore, revision repair is most proper in patients with the functional deficit accompanied with the shoulder weakness as well as the persistent pain. The important factor that is considered in revision repair is a quality of torn cuff. Especially, Care must be taken to ensure that the revision repair is possible, considering the size of tendon defect, atrophy of the muscle, fatty infiltration and extent of the retraction of tendon. Revision repair of a failed rotator cuff repair is more difficult, and the functional results are less satisfactory than those of primary repair, because excessive bursal scarring and tendon retraction may be exhibited, a large or massive tear is often detected, tear has usually been present for a long time, and a quality of muscle-tendon may be poor. So, we discuss our experiences related to revision repair after a failed cuff repair that has been recently introduced through the articles.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.97-105
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• 2006

PSC box girder bridges usually have a lot of tendons, and the difference of the bursting forces lies in the prestressing order of the tendons. As a result of the lack of studies on the prestressing order for the bridges, the order depends on the designer's intuition and experiences. In this paper, with investigation into various methods determining the bursting force of the anchorage, reasonable prestressing order is determined by analysis of PSC beam bridge and PSC box girder bridge with most suitable method. It may be stated that this study would be useful for determining the reasonable prestressing order of tendons for the PSC box girder bridges.

• Journal of Chest Surgery
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• v.37 no.10
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• pp.872-875
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• 2004

The treatment modalities of the intramural hematoma (IMH) remain controversial. Nowadays, the IMH of the descending thoracic aorta is generally classified in the medical treatment category. We describe a patient with IMH of the descending thoracic aorta who received the medical treatment. During the follow-up, we speculated that the IMH had been aggravated leading to an aortic rupture including hemothorax. Therefore, we performed an emergency operation. Contrary to our expectations, operative findings showed a well-organized aortic wall and serous pleural effusion. The exact diagnosis was IMH of the descending thoracic aorta with penetrating atherosclerotic ulcer (PAU). This case reminded us of the importance of accurate diagnosis and proper treatment.

• Journal of Biomedical Engineering Research
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• v.21 no.2
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• pp.181-187
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• 2000

동맥의 일부분이 팽창하는 동맥류는 파열로 인한 높은 사망률을 야기한다. 동맥류의 발생 및 파열에는 혈관벽의 구조적 약화와 혈류에 의한 응력이 중요한 역할을 하며, 혈류에 의해 혈관벽에 가해지는 전단응력은 간접적으로 혈관벽 구조를 변화시키고, 직접적으로 혈관벽에 응력을 가하므로 동맥류 파열에 영향을 미치는 중요한 혈류역학적 인자이다. 동맥류가 자주 발생하는 복부대동맥류 모델을 제작하여 정상류와 맥동류 유동에서 광색성 염료를 이용한 유동가시화 방법으로 벽 전단변형률을 측정하였다. 벽전단변형률은 동맥류 내부에서 감소하여 음의 값을 가지며, 동맥류 최대확장부 후부에서 다시 증가하여 확장부가 끝나는 위치에서 동맥 벽에 비해 약 1.5배 정도의 큰 전단변형률 값을 가졌다. 동맥류 최대확장부 후부에서는 벽전단변형률의 방향의 바뀌며, 위치에 따른 전단변형률의 변화가 크게 나타났다. 맥동류 유동에서는 동맥류의 위치에 따라 시간에 따른 벽전단형률 파형이 측정되었다. 동맥류 내부에서는 전단변형률의 크기가 작고 그 방향이 시간에 따라 변화가 심하였으므로 혈관벽의 구조변화가 발생하기 쉬운 지역으로 지목된다. 동맥류 최대 확장부 후부는 위치 및 시간에 따른 전단변형률의 변화가 심하며, 혈관벽 응력이 최대값을 갖는 지역이므로 동맥류의 파열이 발생하기 쉬운 지역으로 예측된다.