• 대한전자공학회논문지SD
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• 제41권5호
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• pp.43-50
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• 2004

현재의 반도체 공정은 Deep Sub- Micmn (DSM)으로 발전하면서, 선폭이 줄어들고 구동 주파수가 높아지고 있다. 이로 인해 clock source로부터 clock을 필요로 하는 각 단자(sink)까지의 '지연시간의 최대 차'로 정의되어지는 clock skew가 회로의 속도 향상에 있어 중요 제약요소가 되고 있다. 또한 이를 얼마나 줄이느냐 하는 것은 동기식 회로 설계에 있어 중요한 문제가 되고 있다. 따라서 낮은 clock skew를 위한 배선 기술에 대해 많은 연구들이 이루어지고 있다. 본 논문에서는 clock skew를 줄이기 위한 방법으로서 새로운 Advanced clock Tree Generation(ACTG) 방법을 개발하였다. ACTG는 2단계의 계층적 routing을 통해 최적의 clock tree를 구성한다. 본 논문에서 제안하는 알고리즘을 C 언어로 프로그램하여 구현하 후 벤치마크 테스트 데이터에 대하여 실험한 결과, 주어진 skew 범위를 만족시키면서 지연 시간을 감소시키는 효과를 얻을 수 있었다.

• Journal of Chest Surgery
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• 제11권3호
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• pp.246-252
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• 1978

A three year and seven month old girl with moderate depression deformity of the sternum associated with a huge well defined homogenous hazy mass density of the upper half of the right hemithorax on plain chest x-ray had developed, exertionaI dyspnea (Figs1, 2 and 3). Correction of the funnel chest was carried out with modified Ravitch procedure and resection of the intrathoracic cystic mass was performed through an anterolateral thoracotomy incision in one stage operation satisfactorily (Figs. 7 and 8). On exploration, the mass, $15{\times}12{\times}10$cm in size, was connected to the bronchus at 1cm a bove the carina by a stalk (Fig. 4). The outer surface showed abundant vasculature. The specimen was filled with mucoid material; the inner surface was much trabeculated. glistening and smooth (Fig. 5 and 6). yficroscopically, the cyst was lined with simple or pseudostratified ciliated columnar epithelium. The cystic wall was composed of loose fibrous connective tissue, muscle layers, cartilages with some lymphocytic infiltration (Fig. 9). Isolated cases of funnel chest deformity and congenital bronchogenic cystic disease are not uncommon; however, the assocbtion of the two conditions is yery rare. Therefore. report and review of the literature was done.

• Industrial Engineering and Management Systems
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• 제8권4호
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• pp.228-238
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• 2009

This paper first presents two supply chain design problems: 1) a factory location setting and factory selection problem, and 2) a factory location setting and factory/supplier selection problem. The first involves a number of location known retailers choosing one factory to supply their demands from a number of factories whose locations are to be determined. The goal is to minimize the transportation and manufacturing cost to satisfy the demands. The problem is then augmented into the second problem, where the procurement cost of the raw materials from a chosen material supplier (from a number of suppliers) is considered for each factory. Economic beneficial is taken into account in the cost evaluation. Therefore, the partner selections will influence the cost of the supply chain significantly. To solve these problems, an agent gaming and genetic algorithm hybrid method (AGGAHM) is proposed. The AGGAHM consecutively and alternatively enable and disable the advancement of agent gaming and the evolution of genetic computation. Computation results on solving a number of examples by the AGGAHM were compared with those from methods of a general genetic algorithm and a mutual frozen genetic algorithm. Results showed that the AGGAHM outperforms the methods solely using genetic algorithms. In addition, various parameter settings are tested and discussed to facilitate the supply chain designs.

• Journal of Power Electronics
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• 제18권4호
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• pp.965-974
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• 2018

A new zero-voltage-switching (ZVS) push-pull pulse-width modulation (PWM) converter is proposed in this paper. The wide ZVS condition for all of the switches is obtained by utilizing the energy stored in the output inductor and magnetizing inductance. As a result, the switching losses can be dramatically reduced. A simple auxiliary circuit including two small diodes and one capacitor is added at the secondary side of a high frequency (HF) transformer to reset the primary current during the circulating stage and to clamp the voltage spike across the rectifier diodes, which enables the use of low-voltage and low-cost diodes to reduce the conducting and reverse recovery losses. In addition, there are no active devices or resistors in the auxiliary circuit, which can be realized easily. A detailed steady operation analysis, characteristics, design considerations, experimental results and a loss breakdown are presented for the proposed converter. A 500 W prototype has been constructed to verify the effectiveness of the proposed concept.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.801-803
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• 2005

Fundamentally, success of the competitive electricity market is dependent on efficient market design. However, since electricity incorporates various physical constraints as other commodities, the resource assignment (i.e., dispatch scheduling) is also one of requisites for the successful operation of electricity market. Therefore, efficient dispatch scheduling is an important issue to succeed in the deregulated electricity market and the efficiency of this electricity market may be considerably increased by systematic studies on dispatch scheduling algorithm and corresponding constraints, especially system security. Moreover, contrary to traditional vertically-integrated electric power industry condition, since various decision-makings in deregulated electricity market are directly connected with market participants' benefits, only rational dispatch scheduling algorithm can convince these participants. Therefore, it can provide a basis of grievance prevention. In this paper, we propose an algorithm for security constrained dispatch scheduling with respect to load curtailment. Proposed algorithm decomposes the dispatch problem into a master problem corresponding to basecase optimal power flow (OPF) and several subproblems corresponding a series of contingencies using two-stage optimization technique.

• Journal of Chest Surgery
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• 제26권3호
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• pp.224-227
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• 1993

We experienced one case of orthotopic cardiac transplantation in a patient with end stage dilated cardiomyopathy. This 50 year-old female recipient was suffered from NYHA functional class IV cardiac failure and dependent upon intravenous inotropic support for 2 months [recipient category 1]. Her preoperative condition was grave with left ventricular ejection fraction of 20% and estimated systolic pulmonary arterial pressure [from Doppler study] was 50mmHg. The brain-dead donor was 31 year-old male with head trauma. The body sizes [weight, height] of the donor/recipient were 70 Kg, 165 cm / 43 Kg, 160 cm and appropriately overmatched. Preoperatively, identical ABO/Rh blood group [A+] and nonreacting HLA crossmatching were confirmed. On November 11 1992 cardiac transplantation was performed without complication. Multiple organ procurement team and heart transplantation team were organized the operation schedule appropriately to minimize the ischemic time. The pump time was 126 minutes and aortic crossclamping time of recipient heart was 73 minutes and, as a result, total ischemic time of the transplanted heart was 75 minutes. Postoperatively, the vital signs were stable with minimal inotropic support. The immunosuppressive therapy was commenced from preoperatively and cyclosporine, azathioprine, and corticosteroid were used as a combination therapy as scheduled and monitored with blood drug concentration, WBC count, renal function and most importantly regular endomyocardial biopsy.Now, 5 months after transplantation, the patient is in NYHA functional class II with minimal cardiac drug support.

• 한국토양비료학회지
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• 제27권4호
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• pp.315-320
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• 1994

This survey report introduced briefly peat deposits in SAKHALIN island of eastern SIBERIA continent. Peat industry was promoted as leading resources for development in this island by national control economic plan of central government before CIS. But development of deposit was left suspension of operation due to investment now. In southern area, about 10km from Yuzunosakhalinsk, two deposits of peat field were explored. One of them (Troisk) was suspended at begining stage of peat harvest from 300ha field and the other(Missilop) was producing the compact peat through drying and pulverizing from 350ha peat field which showed long run harvest activities. There are plenty of peat deposits near the Polonai Reika (river) in the central area of this island, At Zbaikaritz, 40km nothern area from Polonaisk, 135ha of peat field was developed. This field was left without working but established field preparation and could be able to be harvested any time if machines and utlities were settled. At southern suburb 10km from Polonaisk, about 40ha field of virgin deposit has been established planning for development. The plan involved estimated amount of peat, deposit depth, water level, drainage and leading road. The most of peat deposits accumulated from sphagnum moss. Texture is coarse but it contains more than 95% of organic carbon near to 0.5% of total nitrogen and acidity showed pH4-5.

• 기본간호학회지
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• 제24권2호
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• pp.95-105
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• 2017

Purpose: A systematic literature review and meta-analysis were conducted to synthesis research findings on relationships of quality of life with multi-dimensional correlates in Korean breast cancer patients. Methods: For the study purpose, 18 studies were selected through a systematic process of searching the literature. Results: Among the general characteristics, variables having a significant relationship with quality of life were age (ES=.19), marital status (ES=.15), education (ES=.19), economic status (ES=.16), job status (ES=.10), and religion (ES=.13). Among the disease characteristics, type of treatment (ES=.12), length of time since diagnosis (ES=.13), stage of disease (ES=.14), length of time since operation (ES=.10), frequency of treatment (ES=.19), wound site and pain (ES=.16) were shown to have a significant relationship with quality of life. Depression (ES=-.60), one of the psychological factor, was the variable most significantly related to quality of life. Conclusion: The findings indicate that the variables which strongly impact quality of life in breast cancer patients are depression and pain.

• Journal of Chest Surgery
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• 제32권6호
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• pp.584-587
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• 1999

DiGeorge증후군은 드문 선천성 기형으로 3번째와 4번째 인후낭의 발생과정 이상에 의한 흉선과 부갑상선의 형성부전과 관련이 있다. 이 증후군은 흔히 선천성 심장기형과 안면기형을 동반한다. 저자들은 DiGeorge증후군을 동반한 선천성 심장기형을 1례 수\ulcorner 치험하였다. 환아는 생후 1개월된 남아로 몸무게는 3.5kg이었다. 동반된 선천성 심장기형은 심실중격결손증, 심방중격결손증, 대동맥축착증 및 동맥관 개존증이었다. 수술은 좌측방 개흉 및 흉골 정중절개를 통하여 일차에 거쳐 시행하였고 환아는 수술 후 별다른 문제없이 회복하였다. 현재 6개월 째 외래 추적관찰 중에 있으며 양호한 상태로 성장하고 있다.

• 대한족부족관절학회지
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• 제14권2호
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• pp.190-193
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• 2010

Both os trigonum syndrome and osteochondral lesion of talus (OLT) are common causes of ankle pain and usually affect ballet dancers or athletes. Lateral osteochondral lesions, which usually result from traumatic event, are mostly located anterolateral talar dome but rare central or posterolateral. Moreover, there are technical difficulties such as position of patient or additional posterior portal to address posterolateral lesion by arthroscopy. Meanwhile, treatment of os trigonum syndrome using arthroscopic approach has been reported in many literatures recently. However, it has not been reported to diagnose both os trigonum syndrome and posterolateral OLT together and treat arthroscopically at one stage. The authors report a case of male patient who was diagnosed as os trigonum syndrome with posterolateral OLT and treated simultaneously by hindfoot arthroscopy. Symptom was improved immediately after the operation, and radiological findings at postoperative 16 months verified remarkable healing.