• Journal of Chest Surgery
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• v.29 no.3
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• pp.297-302
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• 1996

From January 1989 to July 1995, 18 patients underwent aortic repair for type A dissections. The e were 9 male and 9 female patients aged 41 to 68 years(mean, 53.8). Thirteen patients underwent the procedure during the acute period, and 5 during the chronic period. During repair of acute dissection, procedures included graft replacement of the ascending aorta only (6 patients), ascending aorta plus partial aortic arch (3), ascending aorta plus total aortic arch (2), Bentall's operation (1), and Bentall's operation plus total aortic arch (1). During repair of chronic dissection, procedures included Bentall's operation (3 patients), ascending aorta only (1), and ascending aorta plus partial aortic arch (1). During repair of the arch, antegrade cerebral perfusion was applied in 4 patients and hypothermic circulatory arrest in 3 patients. There were 4 operative deaths(22.2%), 2 of hemorrhage. and 2 of left ventricular failure in the operating room. Follow-up has been 100% completed and ranged from 2 to 53 months (mean, 17 months). One late death resulted from sepsis following secon operation. Thirteen of the survivors are doing well.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.296-304
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• 2008

This study was carried out to analyze vegetation and soil characteristic, and ordination of Stewartia koreana community. The Stewartia koreana community was classified into Acer mono subcommunity, Pinus densiflora subcommunity, Sapium japonicum subcommunity, and Stewartia koreana typical subcommunity. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable K, exchangeable Ca, exchangeable Mg concentration, cation exchange capacity, and soil pH were ranged from 14.31~34.27%, 0.33~0.77%, 7.83~22.88(mg/kg), 0.23~1.07(me/100 g), 0.29~2.93(me/100 g), 0.33~1.49(me/100 g), 10.47~22.48(me/100 g), and 4.65~4.96, respectively. The area of the Acer mono subcommunity, found in highlands, showed that contained the highest organic substances, nitrogen, available phosphorous, and cation exchangeable capacity concentration among the communities. The low elevation regions where the Pinus densiflor subcommunity is formed, showed the lowest concentrations of exchangeable Ca, and Mg.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.581-587
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• 1988

The solvolysis of substituted benzyl bromides was studied in binary solvent mixtures of acetone-water and ethanol-water at $25^{\circ}C$ and $45^{\circ}C$. The rate constants increase with electron-donating substituents in benzene ring and increasing of water contents in both of solvent mixtures. The sensitivity parameter (m) of the solvolysis of substituted benzyl bromides to solvent ionizing power (Y) was decreased in going from the electron-donating group to electron-withdrawing one, whereas their nucleophilic sensitivity increased continuously in going to above same substituents. It was shown that electron-donating (electron-withdrawing) groups make the transition state looser (tighter). The above results were consisted with the account for the potential energy surface model and the quantum mechanical approach.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.113-120
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• 2007

For the cases of constructing reinforced earth and gabion walls on the soft ground, an appropriate replacement area of soft ground required to maintain the stability of walls was investigated by FEM analyses. Incremental analyses were performed in FEM, in which construction sequences including consolidation of soft soil layer were simulated. As a first step to suggest the appropriate replacement area, a series of analyses for cases varying the replacement depth were conducted to examine the behaviors of wall and adjacent ground according to the construction sequence. The analysis results were, then, evaluated with the proper limiting values of displacements of wall, settlements and shear strains of ground to guarantee the stability of walls, which were specified based on the literature review. Consequently, the typical construction drawings could be suggested, in which appropriate replacement areas for varying wall heights for the ground condition investigated in this study were represented in terms of the ratio of replacement depth to the height of wall.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.12a
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• pp.595-599
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• 1999

본 논문에서는 카오스 현상을 나타내는 수식을 변형하여 암호시스템이나 PN(pseudo-noise)시퀸스에 적용하기 위하여 복잡한 카오스 신호를 발생시키는 하이퍼카오스 VP 사상(HVPM, Hyper chaos Volume Preserving Maps)과 이들간의 카오스 동기화를 제안한다. 단계별 모듈러(modulus) 함수를 이용하여 랜덤한 카오스 신호를 발생시키기 위하여 이산시간(discrete-time) HVPM 모델을 설정하고, 수치해석 실험으로 아날로그 카오틱시퀸스(CAS. chaotic analog sequence)의 특징을 분석한다. 그리고 HVPM의 신호를 기존의 단순한 PC(Pecora, Carroll)방법을 응용한 치환동기화 (synchronous substitution)를 이용하여 구동 및 응답시스템간의 카오스 동기화(chaos synchronization) 제어를 한다. 수치실험에서 카오스 신호가 갖는 특징들을 확인할 수 있었으며, 치환동기시스템에서 효과적인 카오스 동기화가 수행됨을 증명할 수 있었다.

• Clinics in Shoulder and Elbow
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• v.13 no.1
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• pp.153-160
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• 2010

Purpose: The goal of prosthetic replacement of the shoulder is the restoration of the normal anatomy of the joint. Materials and Methods: The physician should review the variations in normal anatomy because it does vary widely and the placement of the prosthetic needs to be modified to accommodate the variations. Results and Conclusion: Several factors including anatomic, prosthetic and surgical ones can lead to the best clinical results, and these are described.

• Journal of Chest Surgery
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• v.35 no.9
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• pp.675-679
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• 2002

In patient with severe adhesion between lung and aorta, there is some limitation in approaching the distal arch or descending thoracic aorta through the usual left thoracotomy. We report a case of a successfully managed distal arch and descending thoracic aortic aneurysm through the median sternotomy without any manipulations of the lung in a 66 year old man who presented hemoptysis.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.166.2-166.2
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• 2016

알루미늄 합금 표면의 도금피막 밀착성을 향상시키는 전처리 방법으로는 아연 치환법[이하; 징케이트(Zincate)처리]이 사용되고 있다. 2중 징케이트 처리에 의해 아연 치환층이 치밀화 하여, 아연 치환층의 일부가 알루미늄과 합금화 한다. 일본에서는 2중 징케이트 처리의 각 과정에 있어서 알루미늄 합금의 표면 상태를 X선 광전자분광장치(XPS)로 조사하였다. 본고에서는 Fe합금 징케이트 처리의 각 공정에 있어서 알루미늄 합금 표면을 XPS로 조사한 결과, 징케이트 처리에 기초한 피막의 구조와 밀착성 개선효과에 관하여 기술하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.1
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• pp.117-124
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• 2012

In this paper, we propose a simple H parity check matrix from the CPM(circulant permutation matrix), which can easily avoid the cycle-4, and approach to flexible code rates and lengths. As a result, the operations of the submatrices will become the multiplications between several CPMs, the calculations of the LDPC(low density parity check) encoding could be simplest. Also we consider the fast encoding problem for LDPC codes. The proposed constructions could lead to fast encoding based on the simplest matrices operations for both regular and irregular LDPC codes.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.2 s.308
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• pp.11-19
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• 2006

In this paper, we propose a method to estimate camera extrinsic parameter based on projective and permutation invariance point features. Because feature informations in previous research is variant to c.:men viewpoint, extraction of correspondent point is difficult. Therefore, in this paper, we propose the extracting method of invariant point features, and new matching method using similarity evaluation function and Graham search method for reducing time complexity and finding correspondent points accurately. In the calculation of camera extrinsic parameter stage, we also propose two-stage motion parameter estimation method for enhancing convergent degree of LM algorithm. In the experiment, we compare and analyse the proposed method with existing method by using various indoor images to demonstrate the superiority of the proposed algorithms.