• Journal of Advanced Marine Engineering and Technology
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• 제21권5호
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• pp.535-541
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• 1997

The effect of concentration of each solution( HCI, $H_2SO_4$ and $HNO_3$), scan rate and polished surface condition on the corrosion of AISI 304 Stainless Steel were investigated, utilizing the Method ASTM G5 - 87. It can be concluded that: 1) For the same concentration(i.e. 1N) of each solution the corrosion rate is the highest in HCI and lowest in $HNO_3$. Also, the difference of values of $i_{cirt}$ generated for each solution is significant. 2) As the concentration of the solution $H_2SO_4$ is increased (O.5N, 1N, 2N) the values of $E_{cor}$ $i_{crit}$ and $i_{p}$ are increased. 3) In case of existence of SCN ion of O.OlN, the values of iCTIt and ip generated are approximately 100 times and 1.4 times higher respectively, than in the case of non - existence of $SCN^{-}$. However the existence of $SCN^{-}$ doesn't affect the value of $E_{cor}$ and $E_{p}$. 4) The values of $i_{crit}$ and $i_{p}$ are increased due to the increase of scan rate. But the values of $E_{cor}$ and $E_{p}$ do not depend on the scan rate. 5) The $i_{p}$ value depends greatly on oxygen in the solution, but the changes in values of $E_{cor}$ $i_{crit}$ and $E_{b}$ due to the oxygen are insignificant. 6) If a component is polished using #400, #600 and #800 wet polish paper, the effect of surface condition on variations of values of $i_{crit}$ and $i_{p}$ is slightly significant.

• 한국문헌정보학회지
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• 제9권
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• pp.53-74
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• 1982

On admet Jusqu'ici que le XVe siecle est une $\acute{e}poque$ phare de l'histoire de l'imprimerie avec l'apparition de la typographie en Orient et en Occident, $c'est-\acute{a}-dire$ en $Cor\acute{e}e$ sur le Rhim. Cependant, $l'\acute{e}poque$ de l'invention typographique en $Cor\acute{e}e$ doit $\hat{e}tre$ $devanc\acute{e}e$ encore d'un ou deux siecle. Outre cette question, il est $\acute{a}$ noter ici que les caracteres mobiles $m\acute{e}talliques$ Kyemi, fondus en 1403, ont $jou\acute{e}$ un $r\hat{o}le$ $tr\acute{e}s$ important dans l'histoire de la typographie mondiale et que les $caract\acute{e}res$ kabin qui leur $succ\acute{e}derent$ en 1434 menerent la typographie $cor\acute{e}enne$ a son $apog\acute{e}e$. Or, les recherches $cor\acute{e}ennes$ se satifait de la primaute de l'invention en Coree des caracteres mobiles metalliques, mais n'adoptent pas une attitude suffisament critique. Aussi, l'auteur a-toil voulu s'interroger sur la veritable valeur de la typographie de la dynastie de Choson tant au point de vue de l'histoire de l'imprimerie mondiale. En premier lieu, on etudie, comme une chronique, les caracteres mobiles metalliques importants tout au long de la dynastie de Choson sans donner une interpretation nouvelle. C'est dans deux derniers, qu'on essaie de developper ses idees sur la typographie en Coree notamment la question technologique qui devrait etre le fond des recherches. Aussi, on y etudie, la technique de la typographie ancienne en Coree interpretee selon une methode scientifique et moderne et, enfin, le bilan synthetique en cherchant les raisons qui freinerent son developpement en Coree malgre la performance de ses debuts. A l'issue de ces recherches, on ne peut s'empecher d'eprouver une certaine insatisfaction a cause de l'ambiguite des explications que l'on trouve dans des documents fondamentaux. Avec ce difficulte on a voulu, au moins, exposer des points discutatables qui devraient etre les recherches a futur.

• 대한전자공학회논문지TC
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• 제37권6호
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• pp.381-381
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• 2000

본 논문에서는 ATM 망에서 다중화된 VBR MPEG 비디오소스 전송시 QoS를 보장하는 실시간 대역폭 할당 방법을 제안하였다. 실시간 처리를 위해 다중화소스를 일정시간으로 나눈 '측정구간별로 나누어서 단일 비디오 소스에 사용하였던 선형예측 방법을 수행하고, 이 과정에서 만족할만할 셀 손실율을 얻지 못할 경우 QoS를 보장하기 위한 대역폭 할당방법으로 과할당과 재할당의 두 가지 방법을 제안하였다. 특성이 서로 다른 네 가지 비디오 소스를 랜덤하게 다중화시켜 생성한 랜덤 다중화소스와, 프레임내 I 픽쳐의 배열을 고려해서 생성시킨 GOP 다중화소스를 만들어 모의실험을 하였고 이를 통해 선형예측 방법의 성능평가와 과할당 및 재할당방법의 성능을 비교하였다. 실험 결과, 과할당방법과 재할당 방법 모두 측정구간을 1.8초 이상으로 하면 0.9이상의 대역폭 이용계수값에서 목표 CLR을 만족하면서 낮은 COR(Cell Over Rate)을 얻을 수 있었고, 특히 COR의 경우 재할당방법이 같은 조건하에서 더 좋은 성능을 보임을 알 수 있었다.

• 대한전자공학회논문지TC
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• 제37권6호
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• pp.21-27
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• 2000

본 논문에서는 ATM 망에서 다중화된 VBR MPEG 비디오소스 전송시 QoS를 보장하는 실시간 대역폭 할당 방법을 제안하였다. 실시간 처리를 위해 다중화소스를 일정시간으로 나눈 '측정구간별로 나누어서 단일 비디오 소스에 사용하였던 선형예측 방법을 수행하고, 이 과정에서 만족할만할 셀 손실율을 얻지 못할 경우 QoS를 보장하기 위한 대역폭 할당방법으로 과할당과 재할당의 두 가지 방법을 제안하였다. 특성이 서로 다른 네 가지 비디오 소스를 랜덤하게 다중화시켜 생성한 랜덤 다중화소스와, 프레임내 I 픽쳐의 배열을 고려해서 생성시킨 GOP 다중화소스를 만들어 모의실험을 하였고 이를 통해 선형예측 방법의 성능평가와 과할당 및 재할당방법의 성능을 비교하였다. 실험 결과, 과할당방법과 재할당 방법 모두 측정구간을 1.8초 이상으로 하면 0.9이상의 대역폭 이용계수값에서 목표 CLR을 만족하면서 낮은 COR(Cell Over Rate)을 얻을 수 있었고, 특히 COR의 경우 재할당방법이 같은 조건하에서 더 좋은 성능을 보임을 알 수 있었다.

• Journal of Chest Surgery
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• 제55권2호
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• pp.151-157
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• 2022

Background: We investigated surgical outcomes after the surgical repair of cor triatriatum sinister (CTS). Methods: Thirty-two consecutive patients who underwent surgical repair of CTS from 1993 through 2020 were included in this study. The morphological characteristics, clinical features, and surgical outcomes were described and analyzed. Results: The median age and body weight at operation were 9 months (interquartile range [IQR], 3-238 months) and 7.5 kg (IQR, 5.8-49.6 kg), respectively. There were 16 males (50%). According to the modified Lucas classification, type IA (classical CTS) was most common (n=20, 62.5%). Atrial septal defect was associated in 22 patients (68.8%) and anomalous pulmonary venous return in 8 patients (25%). Pulmonary hypertension was preoperatively suspected with a high probability in 18 patients (56.3%). There was 1 early death (3.1%) after emergent membrane excision and hybrid palliation in a high-risk hypoplastic left heart syndrome patient. There were no late deaths. The overall survival rate was 96.9% at 15 years post-repair. No early survivors required reoperation during follow-up. Most survivors (31 of 32 patients, 96.9%) were in New York Heart Association functional class I at a median follow-up of 74 months (IQR, 39-195 months). At the latest echocardiography performed at a median of 42 months (IQR, 6-112 months) after repair, no residual lesion was observed except in 1 patient who had moderate pulmonary hypertension (mean pulmonary arterial pressure of 36 mm Hg). Conclusion: Surgical repair of cor triatriatum could be performed safely and effectively with an extremely low risk of recurrence.

• Tuberculosis and Respiratory Diseases
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• 제48권6호
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• pp.944-955
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• 2000

연구배경 : 만성폐성심을 시사하는 심전도 소견 유무에 따른 만성 폐쇄성 폐질환 환자의 예후를 평가하고 이 심전도 소견이 폐기능검사 성적 및 동맥혈가스분석 소견등과 연관되어 예후에 어떤 영향을 미치는 가에 대해서 알아 보고자 하였다. 방법 : 만성폐쇄성 폐질환의 급성악화로 입원한 61명의 환자를 대상으로 심전도, 동맥혈가스분석 및 폐기능검사 성적을 비교하였다. 폐성심을 시사하는 심전도 소견은 우심방부하, 우각차단, 우심실비대 low-voltage QRS로 하였으며 심전도상 이상소견이 없는 1군은 36명이었고, 이상소견이 하나 이상인 2군은 25명 이었다. 결과 : 다변량분석 결과 나이 (risk ratio=1.13, 95% confidence interval 1.05-1.23), DLco % pred. (risk ratio=0.97, 95% confidence interval 0.94-0.99), $PaO_2$ (risk ratio=0.95, 95% confidence interval 0.90-0.99), 심전도상 우심방부하(risk ratio=5.27, 95% confidence interval 1.40-19.85) 가 만성폐쇄성 폐질환 환자에서 각각 독립적으로 생존율에 영향을 미치는 인자로 나타났다. 심전도상 우심방부하의 소견이 없는 경우에서는 1년, 2년, 5년 생존율이 각각 95.4%, 81.4%, 50.0% 인데 비해 우심방부하 소견이 있는 경우는 각각 82.4%, 70.6%, 27.5% 로 유의한 차이가 있었다. 결론 : 이상의 결과로 만성폐쇄성 폐질환 환자에서 폐성심을 시사하는 심전도 소견, 특히 우심방부하를 나타내는 심전도 소견은 중요한 예후예측 인자일 것으로 생각된다.

• Journal of Chest Surgery
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• 제18권2호
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• pp.293-298
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• 1985

Cor triatriatum is a rare congenital malformation of the heart in which a septum stretches in a transverse plane through the left atrium, thus creates two left atrial subchambers. The upper one connects with the pulmonary veins, and the lower connects with the left ventricles. Due to the rarity of, and difficulty in diagnosing car triatriatum, data on the surgery of the disease are of necessity and very limited. A case of cor triatriatum combined with atrial septal defect and persistent left superior vena cava was experienced in November, 1984 in Chonnam University Medical School. There was a transverse septum in the left atrium below atrial septal defect, all pulmonary veins were drained into the upper chamber of the left atrium which connected with the right atrium via atrial septal defect and the lower chamber via an oval opening[8mm] in the abnormal septum and the lower chamber was connected with the left atrial appendage, and the left ventricle via mitral valve. There was persistent left superior vena cava drained to left atrium and coronary sinus. The abnormal transverse septum within the left atrium was completely excised and the atrial septal defect was repaired with Woven Dacron patch. The post-operative course was not eventful and the patient was discharged to home with good result on the 15th postoperative day, and has been in good condition upto now.

• 플랜트 저널
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• 제12권1호
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• pp.37-43
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• 2016

플랜트 하부 강파일 기초 주변 토양의 부식성을 평가하기 위해서 현장조사, 현장 보링작업을 통한 시료 채취 및 실험실 분석을 거친 결과를 검토하였다. 토양 분석 결과 강관파일이 타설된 토양은 여러 개의 특성이 다른 토양층으로 구성되어 있었으며, 각 지층의 화학적, 물리적 성질이 다르므로 강관파일의 타설깊이에 따른 부식성의 차이가 발생할 것을 예상할 수 있었다. 분석 결과를 토대로 정성적인 부식성 평가, 평균부식속도 및 최대부식속도를 예측한 결과, 일부 지층에서는 일반적으로 강관파일 설계시 적용되는 부식속도인 0.01-0.02mm/y 이상의 평균부식속도를 보이고 있었다 (0.33mm/y).

• Journal of Chest Surgery
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• 제16권3호
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• pp.331-336
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• 1983

Cor triatriatum is a rare congenital malformation of the heart, in which a septum stretches in a transverse or oblique plane through the left atrium, thus separating it into two compartments. The upper one connects with the pulmonary veins, and the lower one connects with the left ventricle. Due to the rarity of, and great difficulty in-diagnosing, cor trlatrlatum, data On the surgery of this disease are of necessity very limited and so accurate pre-operative diagnosis was very difficult to make. `We experienced a case of the cyanotic congenital heart disease which was diagnosed as a large atrlal septal defect with streaming venous blood from inferior vena cava to left atrium through atrial septal defect in August, 1982. We found that there were transverse septum in the left atrium through atrlal septal defect, the pulmonary venous drainage were located in the upper chamber of the left atrium, and the lower chamber was connected with the left atrial appendage, mitral valve and `left ventricle. But our case had not any opening in this transverse septum and the right atrium was connected with the upper chamber of the left atrium through the upper part of the atrlal septal defect, and was communicated with the lower chamber of the left atrium through the lower part of the atrlal septal defect. We excised the transverse septum and repair this atrial septal defect with Woven Dacron patch accompanying with the drainage of coronary sinus to right atrium. The post-operative course was not eventful and he was discharged with good result on the post-operative 8th day, and has been in good .condition up to now for longer than 10 months.

• Computers and Concrete
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• 제7권2호
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• pp.191-202
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• 2010

A laboratory investigation was conducted to characterize the constitutive property behavior of Cor-Tuf, an ultra-high-performance composite concrete. Mechanical property tests (hydrostatic compression, unconfined compression (UC), triaxial compression (TXC), unconfined direct pull (DP), uniaxial strain, and uniaxial-strain-load/constant-volumetric-strain tests) were performed on specimens prepared from concrete mixtures with and without steel fibers. From the UC and TXC test results, compression failure surfaces were developed for both sets of specimens. Both failure surfaces exhibited a continuous increase in maximum principal stress difference with increasing confining stress. The DP tests results determined the unconfined tensile strengths of the two mixtures. The tensile strength of each mixture was less than the generally assumed tensile strength for conventional strength concrete, which is 10 percent of the unconfined compressive strength. Both concretes behaved similarly, but Cor-Tuf with steel fibers exhibited slightly greater strength with increased confining pressure, and Cor-Tuf without steel fibers displayed slightly greater compressibility.