• 대한예방의학회:학술대회논문집
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• 1994.02a
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• pp.481-544
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• 1994

• Communications of the Korean Mathematical Society
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• v.33 no.3
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• pp.973-983
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• 2018

Fuzzy linear regression model has been widely studied with many successful applications but there have been only a few studies on the fuzzy regression model with monotonic response function as a generalization of the linear response function. In this paper, we propose the fuzzy regression model with the monotonic response function and the algorithm to construct the proposed model by using ${\alpha}-level$ set of fuzzy number and the resolution identity theorem. To estimate parameters of the proposed model, the least squares (LS) method and the least absolute deviation (LAD) method have been used in this paper. In addition, to evaluate the performance of the proposed model, two performance measures of goodness of fit are introduced. The numerical examples indicate that the fuzzy regression model with the monotonic response function is preferable to the fuzzy linear regression model when the fuzzy data represent the non-linear pattern.

• Journal of the Korean Society of Industry Convergence
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• v.12 no.1
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• pp.27-33
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• 2009

In this paper, a computational analysis using a lumped system model is performed to investigate the hemodynamics of coronary circulation under the operation of T-PLS relevant to the cardiac arrest cases. The coronary circulation system is assumed to be comprised of three compartments: coronary arteries, coronary capillaries, and coronary veins. The effect of myocardial muscle contraction or relaxation is represented by temporal variations in the bias pressure. To verify the present method, we analyzed the coronary circulation for normal case and then compared the results with the existing data. Numerical results on the cardiac arrest model showed that T-PLS can increase LAD flow significantly.

• English Language & Literature Teaching
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• v.9 no.1
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• pp.49-66
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• 2003

This paper explores the language acquisition mechanism within a recent theoretical nativist framework that assumes some computational principles. We will review previous accounts of the logical problem of language acquisition, arguing that language acquisition is part of general cognitive mechanism or at least associated with maturation of cognitive skills. For a theoretical framework, we will adopt the minimalist program and its principles. To support our theoretical argument, we will introduce empirical evidence from ESL (English as a Second Language) and SLI (Specific Language Impairment) data. The two types of data will illustrate that there might be some relationship between the development of language skills and that of the cognitive skills.

• Journal of Chest Surgery
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• v.32 no.12
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• pp.1127-1130
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• 1999

Percutaneous coronary intervention including intracoronary stenting is currently an accepted treatment modality in the treatment of coronary artery disease and is widely performed to treat the patient with multivessel disease with decreased morbidities and less cost compared with conventional coronary rtery bypass grafting(CABG), Repeated interventions due to restenosis even after successful angioplasty are the major disadvantage of the angioplsty especially when the lesion is located inthe left anterior descending artery(LAD) Recently CABG through left anterior small thoracotomy using the left internal thoracic artery to revascularize the LAD territory without cardiopulmonary bypass so called Minimally Invasive Direct Coronary Artery Bypass(MIDCAB) was intrduced and performed with comparable early outcomes. In this regard the integrated approach with percutaneous coronary intervention and minimally invasive direct coronary artery bypass surgery so called 'Hybrid CABG' was suggested to be an effective treatment in suitable patients with multivessel coronary artery disease. We report three cases of Hybrid CABG.

• Educational Technology International
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• v.18 no.2
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• pp.73-99
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• 2017

The learning analytics dashboard (LAD) is a supporting tool for teaching and learning in its personalized, automatic, and visual aspects. While several studies have focused on the effect of using dashboard on learning achievement, there is a research gap concerning the impacts of learners' characteristics on it. Accordingly, this study attempted to verify the differences in learning achievement depending on learning motivation level (high vs. low) and dashboard intervention (use vs. non-use). The final participants were 231 university students enrolled in a basic statistics course. As a research design, a 2 × 2 factorial design was employed. The results showed that learning achievement varied with dashboard intervention and the interaction effect was significant between learning motivation and dashboard intervention. The results imply that the impact of LAD may vary depending on learner characteristics. Consequently, this study suggests that the dashboard interventions should be offered after careful consideration of individual students' differences, particularly their learning motivation.

• Journal of Chest Surgery
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• v.47 no.2
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• pp.106-110
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• 2014

Background: There are several modalities of coronary artery revascularization for multivessel coronary artery disease. Hybrid coronary revascularization (HCR) with minimally invasive direct coronary artery bypass grafting was introduced for high-risk patients, and recently, many centers have been using it. Limited incisional full sternotomy coronary artery bypass (LIFCAB) involves left internal thoracic artery (LITA)-to-left anterior descending coronary artery (LAD) anastomosis through a sternotomy with a minimal skin incision; it could be considered another technique for minimally invasive LITA-to-LAD anastomosis. Our center has performed HCR using LIFCAB, and in this paper, we report our short-term results, obtained in the past 3 years. Methods: The medical records of 38 patients from May 2010 to June 2013 were analyzed retrospectively. The observation period after HCR was 1 to 37 months (average, $18.3{\pm}10.3$ months). The patency of revascularization was confirmed with postoperative coronary angio-computerized tomography or coronary angiography. Results: There were 3 superficial wound complications, but no mortalities. All the LITA-to-LAD anastomoses were patent in the immediate postoperative and follow-up studies, but stenosis was detected in 3 cases of percutaneous coronary intervention. Conclusion: HCR using LIFCAB is safe and yields satisfactory results from the viewpoint of revascularization for multivessel disease.

• The Research Journal of the Costume Culture
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• v.8 no.2
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• pp.197-204
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• 2000

With the current of the end of a century and social, economic, political, and cultural turbulence, people take advantage of the various ways to express their stagnation. This study introduces the term representativity and it will explain the men's fashion of the end of a century. On a theoretical basis, the concept of the representativity, image, symbol and imitation which are used as a tool for expression will be examined, and together with this, inner representation and outer representation will be categorized. The inner representation of the men's fashion in the end of a century can be taken for the purpose of connecting the image of masculinity. The image of masculinity is widely spread owing to the mass communication of a consumption-oriented society, so its hard to define that image as one thing specific. Hence, in order to discuss the male gender and mens fashion, New Man phenomenon should be noticed of. 1980's New Man influence has lasted till now. New Man images were largely categorized into two images like New Lad and Iron John after the mid 1990's. Therefore, the image of masculinity is largely classified New lad, who desires success and pursues the hedonistic life style and Iron John, who enjoys thrill and follows economical life style. The image of masculinity has influence on the outer representation how it is imitated and symbolized via many designer's works and street fashion. Two masculinity images are dominant over the men's fashion of the end of a century. One is inhumane and rational corporate power look that stems from symbolization and imitation of New Lad. The other is outdoor casual that originated from the symbolization and imitation of Iron John.

• Journal of Chest Surgery
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• v.19 no.4
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• pp.606-617
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• 1986

During the period from November 1981 through June 1986, 18 cases of coronary arterial bypass graft were performed at Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital. They consisted of 13 males and 5 females with the mean age of 49 [range: 28-69 years]. History of myocardial infarction was noted in 50% of the patients and cardiomegaly on chest PA in 2 patients with preserved LV function. On resting EKG, except the evidences of old myocardial infarction, the findings of LVH were noted in 7 cases, acute myocardial infarction in 2, diffuse myocardial ischemia in 1, and significant ventricular arrhythmia in 2 cases. The angina by type of presentation is stable in 3 patients, unstable in 15 patients with resting, postinfarction and progressive angina as the criteria of unstability. The patterns of involvement of significant disease were single vessel involvement [5 cases] double vessel involvement [8 cases], and triple vessel involvement [5 cases] including 5 cases of left main coronary arterial diseases. The pattern of coronary arterial disease in individual patient was one or more stenosis of the proximal left coronary arterial system with or without right coronary involvement, in every case. We performed 9 cases of double bypass and 9 cases of triple bypass with great saphenous vein using single anastomosis technique except in 4 cases, One of the 4 cases is our first case, sequential anastomosis between LAD and diagonal was performed due to shortage of the prepared vein graft. In the other 3 cases, our latest experience, we adopted the left internal mammary artery for the left anterior descending coronary revascularization. The distribution of sites of distal anastomosis revealed more striking predilection to LAD, showing our attention on the significance of the revascularization of LAD system. The ischemic time was 35 minutes per graft and mean number of grafts per patient was 2.5. Of the 18 patients, 13 [77.2%] had complete revascularization, and incomplete in 5 cases with the causes of incompleteness as presented. The early results of operation were as followed: surgical death in 2 [11%], perioperative infarction 2 [11%], need of inotropic support 5 [28%], arrhythmia 2 [11%], wound problem, bleeding, and emotional dysfunction. The actuarial anginal free survival during the period of 6 months through 2 years was 85.2% with excellent symptomatic control according to the angina classification of Canadian Cardiovascular Society.

• Journal of Chest Surgery
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• v.33 no.4
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• pp.277-284
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• 2000

Background: Coronary artery bypases grafting in the old aged is associated with high mortality and morbidity, and it is difficult to perform if the coronary artery is diffusely disease. Recently it has been known that platelet derived growth factor(PDGF), especially PDGF-BB, stimulates angiogenesis. Material and Method: New Zealand white rabbit were used. In an attempt to achieve effevtive cardiac revasculatrization without vascular anastmosis, we divided into three groups(group I : Left anterior descending artery(LAD) was occluded by ligature, group II : Bilateral internal mammary vascular pedicles were dissected and implanted into myocardium, group III : The vascular pedicles were implanted into myocardium and PDGF-BB was injected into the myocardial tissue). Two weeks after IMA implantation, the proximal region of implanted LAD was ligated. Four days after LAD ligation angiogram, triphenyl tetrazolium chloride(TTD) staining and hematoxylin eosin staining were performed. Result: 1. Survival rate in group II was significantly higher than that in group I (P<0.05), and survival rate in group III was signficantly higher than that in group II(53% vs 93%, P<0.01). 2. There were significant differences in the ratio of area of necrosis to area at risk between group I and group II, and between group II and group III (P<0.01). 3. Microangiogram for angiogenic response revealed wide area of extensive revascularization with patent vessels in group III. 4. Histologic findings of three groups showed that polymorphonuclear leukocyte infiltration was minimal in group II and none in group III. Conclusion: PDGF-BB can establish functinal cardiac revasculatization through systemic vessels implanted directly into the myocardium.