• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.84-87
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• 2000

Square tubes used for vehicle structure components have an important role on keeping its stiffness and preserving occupant safety in vehicle collision and rollover in which it experience axial collapse, bending collapse or both. Bending collapse, which absorbs kinetic energy of the impact and retains a survival space for the occupant, is a dominant failure mode in oblique collision and rollover. Thus, in this paper, the bending collapse characteristics such as the maximum bending moment and energy absorption capacity of the square tube replaced by light-weight material were evaluated and presented. The bending test of cantilever tubes which were fabricated with aluminum, GFRP and aluminum/ GFRP hybrid by co-curing process was performed. Then the maximum bending moment and the energy absorption capacity from the moment-angle curve were evaluated. Based on the test results, it was found that aluminum/ GFRP hybrid tube can show better specific energy absorption capacity compared to the pure aluminum or GFRP tube and can convert unstable collapse mode which may occur in pure GFRP tube to stable collapse mode like a aluminum tube in which plastic hinge is developed.

• Geomechanics and Engineering
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• 제9권1호
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• pp.83-100
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• 2015

Water and energy supplies are the key factors affecting the economic development and environmental improvement of Turkey. Given their important role and the fact that a large part of Turkey is in seismically active zones dams should be accurately analyzed since failure could have a serious impact on the local population environment and on a wider level could affect the economy. In this paper, a procedure is proposed for the static, slope stability, seepage and dynamic analysis of an earth dam and the Pamukcay embankment dam. The acceleration time history and maximum horizontal peak ground accelerations of the $Bing\ddot{o}l$ (2003) earthquake data was used based on Maximum Design Earthquake (MDE) data. Numerical analysis showed that, the Pamukcay dam is likely to experience moderate deformations during the design earthquake but will remain stable after the earthquake is applied. The result also indicated that, non-linear analysis capable of capturing dominant non-linear mechanism can be used to assess the stability of embankment dams.

• 대한조선학회논문집
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• 제54권2호
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• pp.143-150
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• 2017

Previous methods to evaluate the risk of dropped objects rely on personnel experience of the engineer or operator without analyzed data. However analyzing historical statistic data is the best approach to find the safest operation route and to achieve more reasonable and reliable calculation results. By counting the failure frequency and fatal accident rate the risk can be quantified, and so controlled or mitigated with best economical risk reducing measures. This analysis gives a crane operator with useful information for selecting the best crane operation route, and a designer with an estimation of risk level for the dropped objects from a safety point of view.

• Journal of Chest Surgery
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• 제16권3호
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• pp.337-341
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• 1983

The experience with operative treatment for total correction of Tetralogy of Fallot at the department of Thoracic and Cardiovascular Surgery, Korea University Hospital from January, 1977, through April, 1983 was reviewed. Of the 29 patients reviewed, male to female occurrence ratio was 22:7 Type of V.S.D. was type II in 26 cases[90%] and total conus defect in 3 cases[10%]. Average size of V.S.D. was 19 mm. Type of Right ventricular outflow tract stenosis was highest frequency with pulmonary valvular and infundibular stenosis combined type in 21 cases[72%], and there were 8 deaths In this group. Type of R.V.O.T. reconstruction contains 2 cases of infundibulectomy only, 1 case of infundibulectomy with valvular commissurotomy, 2 cases of pericardial patch, 23 Cases of pericardial patch with Teflon or Dacron felt reinforced and 1 case of pulmonary valved conduit reconstruction. Operative mortality was higher in outflow patch through pulmonary valve ring. Overall mortality was 31%. Major causes of death and postoperative complications were low output syndrome, complete A-V block acute renal failure, ventricular fibrillation, bleeding brain abscess, and sudden cardiac arrest.

• Journal of Chest Surgery
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• 제22권5호
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• pp.781-787
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• 1989

Seven patients [six cases of left atrial myxoma, one case of right atrial myxoma] from 24 to 66 years of age [4 male and 3 female, mean age 48 years] underwent excision of atrial myxoma between 1982 and 1989 at Keimyung University Dongsan Medical Center. All patients presented with congestive heart failure, six with cardiac murmur, three with syncope, two with sinus tachycardia, one each with sinus arrhythmia, atrial fibrillation, pleural effusion, peripheral embolization. Symptoms were present from 1 month to 8 years before operation [mean 28 months], All tumors originated from atrial septum and pedunculated. The myxomas were successfully removed in all patients, either shaving them from atrial septum [n=3] or by excising a portion at normal atrial septum with tumor [n=4]. One case was replaced mitral valve with carbomedics-31mm due to severe mitral regurgitation. Follow up is current. No recurrent myxoma has been identified clinically or by echocardiography. In this series, excellent results were obtained by simple excision of the tumor, with or without a margin of normal atrial septum.

• Journal of Chest Surgery
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• 제3권2호
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• pp.139-142
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• 1970

A Case of thoraco-abdominal aortic aneurysm involving from the lower descending- thoracic aorta to bifurcation of abdominal aorta into both common iliac artery is presented in special view-point of its surgical technic and postoperative complication. Operative technic is the most popular method of Dr. De Bakey's shunt of Dacron which is bridging thoracic aorta to terminal abdominal aorta primarily as temporary shunt but after anastomosing the individual hranch of left Renal, Celiac, Sup. meseateric and right Renal artery to corresponding part of the Dacron tube, the Dacroa graft is fixed as permanent graft in stead of excised thoraco-abdominal aorta. The patient died of acute renal failure and increasing evidence of CNS damage due to respiratory acidosis on 6th postoperative day hut this report will he a good experience in respect of further progress of aortic surgery in Korea.

• Journal of Chest Surgery
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• 제27권5호
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• pp.399-401
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• 1994

We experienced one case of surgical treatment of A-V fistula between the right common iliac artery and the right common iliac vein after lumbar laminectomy. The average vascular surgeon does not have extensive experience with this disorder owing to its rarity. Arteriovenous fistula of the aorta and its major branches present an unparalleled challenge in patient care. Because of their central location, blood flow through these fistulas may be massive;the associated complications are usually dramatic, resulting in severe refractory congestive heart failure, massive venous hypertension, or extensive hemorrhage during an illfated surgical repair.For this reason, it behooves one to become well acquainted with the problem in order to avoid morbid complications and thus ensure optimal patient care.

• Structural Engineering and Mechanics
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• 제59권1호
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• pp.123-132
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• 2016

Many military and commercial aging aircrafts flying beyond their design life may experience severe crack and corrosion damage, and thus lead to catastrophic failures. In this paper, were used in a finite element model to evaluate the effect of corrosion on the adhesive damage in bonded composite repair of aircraft structures. The damage zone theory was implemented in the finite element code in order to achieve this objective. In addition, the effect of the corrosion, on the repair efficiency. Four different patch shapes were chosen to analyze the adhesive damage: rectangular, trapezoidal, circular and elliptical. The modified damage zone theory was implemented in the FE code to evaluate the adhesive damage. The obtained results show that the adhesive damage localized on the level of corrosion and in the sides of patch, and the rectangular patch offers high safety it reduces considerably the risk of the adhesive failure.

• 대한한방부인과학회지
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• 제30권3호
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• pp.128-135
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• 2017

Objectives: This study is to report the effects of acupuncture, moxibustion and herbal medicine on infertility. Methods: From February 2015 to December 2016, 44 women with infertility were treated with acupuncture, moxibustion and herbal medicine. 6 months later, follow up and analysis were performed. Results: Of the total 44 women, 19 were successful in pregnancy. Of the 30 women who were contacted by follow-up after 6 months, 19 (63.3%) were successful in pregnancy. 6 of the 8 women who had abortion experience and 5 of the 6 women without the symptoms were pregnant. And 2 with dysmenorrhea, women with follicular development failure, hydrosalpinx, ectopic pregnancy, anovulatory infertility patients, polycystic ovary syndrome were all successfully pregnant. Conclusions: This study suggests that acupuncture, moxibustion and herbal medicine are useful and shows possibility to increasing pregnancy rates.

• Journal of Dental Anesthesia and Pain Medicine
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• 제21권5호
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• pp.471-474
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• 2021

Methemoglobinemia is rare. It is classified into two types: congenital methemoglobinemia and acquired methemoglobinemia. Methemoglobin is incapable of binding oxygen, leading to complications such as cyanosis, dyspnea, headache, and heart failure. In the present case, a 35-year-old man with congenital methemoglobinemia underwent general anesthesia for thyroidectomy. The patient was diagnosed with hemoglobin M at 7 years of age. Ventilation was performed with FiO₂ 1.0. Arterial blood gas analysis showed that the pH was 7.4, PaO₂ 439 mmHg, PaCO₂ 40.5 mmHg, oxyhemoglobin level of 83.2%, and methemoglobin level of 15.5%. The patient had a stable course, although cyanosis was observed during surgery.