http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
여승동,임승평,Yeo, Seung-Dong,Im, Seung-Pyeong 대한흉부심장혈관외과학회 1991 Journal of Chest Surgery (J Chest Surg) Vol.24 No.4
Atrial fibrillation[Af] is closely related to thrombus in left atrium, systemic embolism, and loss of the contribution of atrial contraction to cardiac output. Therefore maintenance of sinus rhythm[SR] is undoubtedly hemodynamically superior to Af in the clinical course of mitral valvular disease especially in the unstable period immediately after surgery. In this article, the conversion rate and the factors influencing the conversion of Af to SR after surgery were studied. Ninety-three patients with mitral valvular replacement at Chungnam National University Hospital were analysed with electrocardiography before and after surgery during the period from June 1985 to June 1990. Eighty patients presented Af before surgery. Twenty-four[30Yo] of the patients were converted to SR[A group] and fifty six presented continuous Af after surgery[B group]. The duration of preoperative Af, preoperative left atrial dimension[LAD], preoperative functional status[NYHA classification] and cardiothoracic[CT] ratio were factors influencing the conversion of Af to SR after surgery. The mean preoperative duration of Af was 3.5$\pm$2.6yr in group A and 7.6$\pm$4.9yr in group B. The mean preoperative LAD was 53. 7$\pm$9.4mm in group A and 62.5$\pm$11.2mm in group B. Before surgery, eleven patients[46%] were belong to NYHA class I, II in group A and eight[14%] in group B. The preoperative CT ratio was 62$\pm$6% in group A and 69$\pm$8% in group B.
이재갑(Jae-Kab Lee),여승동(Seung-Dong Yeo) 한국자동차공학회 1997 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1997 No.6_2
The vibrational characteristics of of the engine structure are highly responsible for the emitted overall noise. Together with oil pan the engine structure in general radiates more than 50% of total engine noise. Additionally the structural vibrations coupled with crank shaft flexible motion are easily transferred from the block through engine mounts into the car, in turns has the bad dffects on the sound quality. In this paper the mechanisms of the crank shaft rumbling are explained, and the influences of dynamic characteristics of engine structure on its noise are investigated, followed by discussions on the test results of the features necessary for the design of low noise engine.<br/>