• Journal of Chest Surgery
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• v.31 no.7
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• pp.650-659
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• 1998

Between August 1996 and August 1997, 22 patients underwent extracardiac Fontan operations. The basic diagnoses included univentricular heart of the right ventricular type (n=12); univentricular heart of the left ventricular type (n=4); tricuspid atresia (n=4); left isomerism, transposition of great arteries, ventricular septal defect and pulmonary stenosis (n=1); and criss-cross heart with uneven ventricle (n=1). The median age of the 14 men and 8 women was 29 months (range from 21 months to 26 years). Previous procedures included bidirectional cavopulmonary shunt (n=15, interval=15.6$\pm$3.4 months), Kawashima operation (n=4, interval=37.5$\pm$20 months), and classic Glenn shunt (n=1, interval=14 years). In 2 patients, extracardiac Fontan operations were done without any previous procedures. A 16- to 22-mm flexible Gore-Tex tube graft (n=18), Hemashield graft (n=3), or, alternatively, a nonvalved aortic allograft (n=1) was cut and anastomosed end-to-end between inferior vena cava and undersurface of pulmonary artery using Gore-Tex or Prolene suture in a running fashion. In risk Fontan patients (n=12), a communication between the extracardiac conduit and the right atrium was constructed. In the most 13 recent patients, the procedures were done without cross-clamping of the aorta and with a beating heart. Operative mortality was 9.1% (n=2). Complications included persistent chest tube drainage for more than 7 days (n=5), chorea (n=2), and low cardiac output (n=1). There were no late deaths. Follow-up echocardiogram (mean: 6 months) demonstrated satisfactory hemodynamic results in the surviving 20 patients. Potential advantages of this technique consist of minimization of surgical manipulation of atrial tissue, reduction or elimination of myocardial ischemia, creationof a uniform and stable inferior vena cava-to-pulmonary artery conduit, and increased flexibility and safety in certain high-risk patients such as those with increased pulmonary vascular resistance, pulmonary hypertension, and impaired ventricular function. Further investigations during a longer follow-up are needed to confirm the intermediate and long-term results, especially the reduction of late atrial arrhythmias.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.187-187
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• 1999

fcc(110) 표면이나 bcc(110) 표면과 같이 2-fold 대칭성을 갖는 표면 위에 초미세 박막을 성장시킬 경우 토대표면의 두 방향에 대한 비 대칭성으로 흡착물이 비대칭적인 cluster 형태로 성장되는 것이 보고되고 있다. 최근 STM에 의한 Ps(110) 표면 위에나 Si(100) 또는 W(110) 표면 위에 성장 실험은 흡착물이 길게 늘어선 한 줄 형태의 성장 또는 가로 세로가 비대칭적인 cluster 형태로 성장되는 것을 보고하고 있고, 이러한 특정 형태의 성장의 원인으로 흡착 원자의 방향에 따른 분산 속도의 비대칭성, 인접 원자와의 비대칭적인 상호작용, 또는 cluster 경계 방향의 분산 속도 등을 들고 있다. 그러나 아직 대부분의 물질계에 비해 흡착원자의 분산속도 또는 분산 장벽에 대해서는 잘 알려져 있지 않다. 원하는 원자 단위 구조물 제작을 위해서는 흡착물의 분산속도에 대한 이해가 필수적이며, 본 연구는 KMC 시뮬레이션과 실험 결과를 비교하는 방법을 통하여 위치와 조건에 따른 각각의 분산 속도를 구하고자 하는 시도이다. 특히 비대칭적 토대 위에서의 나타나는 다양한 형태의 미시적 성장구조에 관심을 가지며, 연구 방법으로는 KMC 시뮬레이션을 이용한다. 미시적 성장 양식은 분산 장벽 형태에 의해 크게 결정된다. 분산장벽 중에서 성장에 비교적 큰 영향을 미치는 것으로는 테라스 위의 원자가 이동할 때의 분산장벽인 Ed, 계단 끝에 부착된 원자가 분리될 때의 장벽인 Ep, 그리고 위 테라스에서 계단 아래로 떨어져 내려갈 때 만나는 Schwoebel 장벽들이 있다. 먼저 대칭적인 fcc(100) 표면 위에서의 성장 구조를 정리해보면 분산 장벽에 따라 다양한 미시적 성장형태를 볼 수 있었다. 다층 성장의 경우도 그 양식은 sub-ML 성장과 동일한 형태를 가지므로 sub-ML 성장구조로 전체 성장 양식을 예견할 수 있다. 일반적인 경향은 Ep가 커질수록 fractal 성장형태가 되며, Ed가 적을수록 cluster 밀도가 작아지나, 같은 Ed+Ep에 대해서는 동일한 크기의 팔 넓이(수평 수직 방향 cluster 두께)를 가진다. 따라서 실험으로부터 얻은 cluster의 팔 넓이로부터 Ed+Ep 값을 결정할 수 있고, cluster 밀도와 fractal 차원으로부터 각각 Ed와 Ep값을 분리하여 얻을 수 있다. 또한 다층 성장에 대한 거칠기(roughness) 값으로부터 Es값도 구할 수 있다. 양방향 대칭성을 갖지 않은 fcc(110) 표면과 같은 경우, 형태는 다양하지만 동일한 방법으로 추정이 가능하다. (110) 표면의 경우 nearest neighbor 원자가 한 축으로 형성되고 따라서 이 축과 이것과 수직인 축에 대한 상호작용이나 분산 장벽 모두가 비대칭적이다. 따라서 분산 장벽도 x-축, y-축 방향에 따라 분리하여 Edx, E요, Epx, Epy 등과 같이 방향에 따라 다르게 고려해야 한다. 이러한 비대칭적인 분산 장벽을 고려하여 KMC 시뮬레이션을 수행하면 수평축과 수직축의 분산 장벽의 비에 따라 cluster의 두께비가 달라지는 성장을 볼 수 있었고, 한 축 방향으로의 팔 넓이는 fcc(100) 표면의 경우 동일한 Ed+Ep값에 대응하는 팔 넓이와 거의 동일한 결과가 나타나는 것을 볼 수 있다. 따라서 이러한 비대칭적인 모양을 가지는 성장의 경우도 cluster 밀도, cluster 모양, cluster의 양 축 방향 길이 비, 양 축 방향의 평균 팔 넓이로부터 각 축 방향의 분산 장벽을 얻어낼 수 있을 것으로 보인다.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.5
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• pp.25-36
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• 2016

The goal of the SmartGrid is to maximize energy efficiency by exchanging bi-directional real-time power information with the help of ICT(Information and Communication Technology). In this paper, we propose a "JRS-MS" (Joint Routing and Scheduling for Multi-channel SmartGrid) algorithm that uses numerical modeling methods in IEEE 802.11s based STDMA multi-channel SmartGrid NAN networks. The proposed algorithm controls the amount of data transmission adaptively at the link layer and finds a high data-rate path which has the least interference between traffic flows in multi-channel SmartGrid NAN networks. The proposed algorithm improve transmission performance by enhancing network utilization. By comparing the results of performance analysis between the proposed algorithm and the JRS-SG algorithm in the previous paper, we showed that the JRS-MS algorithm can improve transmission performance by maximally utilizing given network resources when the number of flows are increasing in the multi-hop NAN wireless mesh networks.

• Korea Journal of Hospital Management
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• v.3 no.1
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• pp.134-164
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• 1998

The purpose of this study is to provide the data for the co-operative treatment of western and oriental hospital. The studies were made a questionnaire to analyze inpatients' awareness on the systems of co-operative treatment and to observe the differences in medical service satisfaction between inpatients who had experienced the co-operative treatment of western and oriental hospital(Group 1) and those who did not (Group 2). The survey was conducted in February 1998, on 250 inpatients who were in a hospital which provided co-operative treatment of western and oriental medicine in Pusan. Korea. The results of this study were disclosed as follows: 54.2% of western hospital inpatients and 90.5% of oriental hospital inpatients suffered from diseases of the nervous system 88.9% of Group 1 and 72.2% of Group 2 believed that the co-operative treatment of western and oriental hospital was more effective in curing diseases of the nervous system. 33.5% or inpatiens in the western hospital and 87.4% of inpatients in the oriental hospital had received the co-operative treatment. In the case of the oriental hospital inpatients who had experienced western treatment, 36.8% received an examination radiologic, 30.7% received a laboratory test, 17.8% received physical therapy, and 14.1% received medication. Whereas, in case of the western hospital inpatients who had experienced oriental treatment, 71.8% received acupuncture, 23.9% received herbal medicine, and 2.8% received oriental medical tests. As to the opinion on the systems of co-operative treatment, 49.6% of Group 1 agreed that 'New medical institutions that adopt the merits of both western and oriental medicine are absolutely necessary.', and 48.9% of Group 1 agreed that 'Since there are strong points and weak points in both western and oriental medicine, partial and gradual introduction of the two systems would be better.' Whereas, 49.6% of Group 2 agreed that the partial and gradual introduction, and 35.7% of Group 2 agreed that the necessity of the new medical institutions. As to the motives for visiting the hospital, the most popular reason for all the inpatients was "others' advice". In the case of Group 1, however, the most popular reason was "the possibility of co-operative treatment". In regards to medical cost, the oriental hospital inpatients felt that their medical cost was too expensive. On the other hand, a smaller percentage of the western hospital inpatients felt that western hospital medical cost were too expensive. And between Group 1 and Group 2, a higher percentage of Group 1 felt that their medical cost was too expensive.

• Korea Journal of Hospital Management
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• v.3 no.1
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• pp.34-61
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• 1998

A study on cooperative medical treatment system between oriental and western medical practitioners was conducted from March through August 1997 in order to determine a productive model of cooperation of two medical parts for treatment of patients. Questionnaires were distributed to 195 medical doctors(M.D.) and 195 doctors of oriental medicine(O.M.D.) working in clinics and hospitals in six major cities. Statistical analysis tools used for this study were frequency, t-test and multiple regression by using SPSS/P.C package. The results are summarized as follows: 1. The respondents were composed of male docotors(78%) and female doctors(22%) and 68.2% of M.D. and 97% of O.M.D. were interested in the other medical part. The doctors of both disciplines had some limitation on treatment of patients but they were reluctant to refer their patients to other doctors in different discipline. 2. M.D assumed that oriental medicine was more effective for chronic diseases, and O.M.D. thought that western medicine was more effective for acute diseases. 92.3% of O.M.D.s responded that even though they do not utilize western medical technology for diagnosis, they believed the results of diagnoses by western medical technology. 3. 60.5% of O.M. and 93.3% of O.M.D. said that cooperative medical treatment system could be necessary for patients and it would be effective for control of diseases and 69% of western medical doctors and 99% of oriental medical doctors agreed that oriental medical practice would be more effective for cerebellar vascular accidents than other diseases. 77.4% of western medical doctors and 92.3% of oriental medical doctors responded that the students of two different disciplines have to be taught on the other disciplines. 82.6% of western medical doctors and 83.3% oriental medical doctors agreed that it would be necessary to have collaborative research between scientists in two disciplines. 81.5% of M.D.s and 93.3% of O.M.D.s believed that they had prejudice and distrust on other discipline 4.90% of the doctors were not satisfied with the government medical policies on health insurance, legal matters, and health delivery system. 5. 75.4% of M.D.s and 50.2% of O.M.D.s said that two medical disciplines should be integrated, but they were skeptical on that. 75.3% of M.D.s thought that western hospitals should employ O.M.D.s Finally this study recommended that western medical students study oriental medicine and the vice versa, and M.D.s and O.M.D.s should have seminars and workshops to exchange knowledge, and experiences. It is also recommended that medical laws be revised to allow medical doctors refer the patients whom they can not handle to oriental medical doctors and the vice versa.

• Information Systems Review
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• v.12 no.2
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• pp.145-166
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• 2010

As the service industry is advancing, the meaning of service innovation has been evolved. Recently, service innovation embraces all creative activities about service offering or relevant to service offerings and emphasizes the importance of customers in innovation process as a key driver. The innovation in services is often the result from a collaborative process between KIBS firms and client firms. Many researchers have pointed out about how the KIBS firms drive the innovation through service. In spite of the importance of service innovation, previous studies did not address the questions about what kinds of factors affect service innovation in KIBS firms still remain, or what are the effects of different knowledge on the innovation process. Therefore, the purpose of this study is to investigate the effect of the interactivity that KIBS firms have with their customers on various types of innovations in KIBS firms. Interactivity has been touted to be the most important starting point for and the basis of service innovations. This study also examines the effect of knowledge types (tacit or explicit) on the relationship between interactivity and service innovation. To test the proposed hypotheses, we developed measurement items and distributed survey questionnaires to domestic companies. 230 survey questionnaires were distributed and 81 were returned among which 76 were usable. The results of this study show that interactivity may be a significant indicator of innovation within KIBS firms. It also represents that the effect of knowledge types on the relationship between interactivity and innovation. These results indicate that KIBS firms need to improve the various activities of interaction with customers for innovation. This study provides a blueprint to further investigation of the critical role of service in service science perspectives.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.5
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• pp.809-822
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• 2018

A quantitative risk assessment has been introduced to quantitatively evaluate fire risk as a means of performance based fire protection design in the design of railway tunnel disaster prevention facilities. However, there are insufficient studies to examine the effect of various risk factors on the risk. Therefore, in this study, the risk assessment was conducted on the model tunnel in order to examine the effects of the evacuation start time delay and the fire growth curve on the quantitative risk assessment. As a result of the analysis of the scenario, the fatalities occurred mainly when escapes in the same direction as the direction of the fire smoke movement. In addition, after the FED exceeded 0.3, the maximum fatalities occurred within 10 minutes. In the range of relatively low risk, distance between cross passages, evacuation delay time and fire growth curve were found to affect the risk, but they were found to have little effect on the condition that the risk reached the limit. Especially, in this study, it was evaluated that the evacuation delay time reduction, fire intensity and duration reduction effect were not observed when the distance between cross passages was more than 1500 m.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.34-47
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• 1996

We have seen a sharp increase in the utilization rate of medical services since the launch of Nation Health Insurance system in 1989. However, the market share of oriental medicine in the Korean health sector has been gradually diminished mainly due to low insurance coverage and high price. Especially high price as an entry barrier to oriental medical services has played a major role in decreasing market share. This paper investigated the effects of price discount on the financial condition and market share of oriental medical institutions. Microeconomic theory and multiple regression analysis were used as a methodology in testing the alternative hypothesis: price discount of enveloped herb drug will result in increases in both the revenue and market share of oriental medical institutions. Data was collected from the statistical yearbook and sample survey. The price elasticity of demand for enveloped herb drug was estimated at 5.8 during 1987-1995 period, which means that a 1% decrease in price will bring about a 5.8% increase in the utilization of oriental medical services. The empirical result shows that a drastic price discount for the enveloped herb drug will eventually improve the financial status of the oriental medical institutions and enlarge the market share of oriental medicine in the Korean health care sector.

• The Journal of the Korea Contents Association
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• v.10 no.3
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• pp.92-100
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• 2010

Due to the development of digital appliance, role of TV causes both-way by introducing IPTV, and SNS service causes big change of watching environment and residence environment. There are good conditions on the role of integrated control because it is arranged in the living room which secures movement most effectively and because family members can easily use, and the degree of use is high. Therefore, we infer user's needs by analyzing user scenario and current role of TV in home network environment. Primarily, we collect surveys of development scenario and technology which companies suggest TV applied by home network service, and secondly, we comparatively study scenario which the companies mentioned above suggest through observing user scenario, and study the role of IPTV in the future through actual scenario-based experiment by ethnography. After analyzing user scenario through case study and experiment, there are integrated device studies mainly in company study because it can be made up inside home, security and entertainment. On the other hand, there are patterns of user behavior by scenario experiment mainly in auto-tainment, security, and it showed that it is insufficient for interaction between TV and home media peripheral. Through this paper, we analyze context of home user, and based on this, we could suggest effective use of service development. Also after analyzing user form, we could know it also should be considered of ratio between activity inside home and activity outside home.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.536-545
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• 2016

Most universities have been concerned about Liberal Education; whether is it on universal truth, or on training job-specialists? In consequence, the curricula have been reformed and promoted diversely. In this aspect, has been developed as convergence education. I selected two easy and short texts and tried to make the students practice and memorize the dialogues as many as possible. At the end of the class, the students presented given assignments, with theatrical performance. This study carried out the research of students' presentation and theatrical performances on the basis of group study, together with a survey of the results of questionnaires and lecture evaluation. Therefore it was a exploratory study to check out significance of variables through the correlation analysis. The students' questionnaires showed the improvement of their English ability, together with their knowledge about literature and drama, cultivating humanities through the theatrical performance. It may be said that has achieved multi-functional effects of English class converged literature, theatre and humanities even for one semester.