• 전기전자학회논문지
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• 제9권2호
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• pp.115-122
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• 2005

모드잠금 고리형 광섬유 레이저 출력의 단열 쏠리톤 펄스압축에 의해 $1545{\sim}1550\;nm$ 파장영역에서 400 ??토초의 안정성이 뛰어난 변환제한급의 10 GHz의 광 펄스를 발생시켰다. 특별한 슈퍼모드 선택소자를 사용하지 않고도 -123 dB/Hz 이하의 슈퍼모드 비팅 잡음 억제에 의해 $1\;kHz{\sim}100\;MHz$의 잡음대역에서 100 ??토초 미만의 낮은 시간 지터를 얻었다.

• 아동학회지
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• 제28권3호
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• pp.235-250
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• 2007

Using content analysis this study examined Korean people's traditional view on children with disabilities, hoping to contribute to the selection of appropriate picture books for an understanding of disabilities in kindergartens and child care centers. Story book characters with disabilities mainly interacted with their families and village people, had lower positions, did not accomplish their work on their own, and suffered from others' anger and beating. Differences in types of disabilities were that physical disabilities were viewed positively, while mental disabilities were viewed negatively. The former had wider scope of activities and maintained more positive relationships with other characters than the latter; furthermore, the former had higher position than the latter and had cooperative interactions with people without disabilities.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.489-491
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• 1996

This paper describes the Induction-beating high frequency resonant Inverter(0.5MHz, 2KW) with full-bridge circuit using Power-MOSFET. In this paper can be applied to several areas such as induction heating, development of power supply in industrial process etc.

• 한국광학회지
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• 제13권1호
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• pp.70-72
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• 2002

좁은 선폭을 갖는 연속 레이저 빔이 제이조화된 Nd:YAG레이저빔과 Bethune셀을 사용하여 좁은 선폭을 갖는 펄스 레이저빔이 생성되었다. 증폭된 펄스빔의 주파수 chirping정도는 헤테로다인 방법을 이용하여 측정되었으며, 헤테로다인 맥놀이신호로부터 순간적인 위상 변화량을 추출함으로서 분석되었다. 10 ns 펄스에 의해 MHz 이하의 선폭을 가지는 연속 레이저빔으로부터 증폭된 주파수 chirping은 80MHz정도로 매우 좁은 선폭의 증폭된 펄스 레이저빔이 얻어졌다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.134.2-135
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• 2003

The plant-pathogenic species S. scabies, S. acidiscabies, and S. turgidiscabies cause the scab disease of potato and produce the phytotoxins, thaxtomins. necl, a gene conferring a necrogenic phenotype, is involved in pathogenicity and physically linked to the thaxtomin A biosynthetic genes. Identification of the pathogenic strains of Streptomyces from soil was performed through the polymerase chain reaction by using specific pathogenicity primer sets derived from the necl gene sequences of Streptomyces smbies. The DNA was extracted from soil using a bead-beating machine and modifications of the FastPrep system. The DNA was suitable for direct use in the PCR. The PCR products showed the bands of approximately 460 bp. This methods can be very usuful in identifying species responsible for scab diseases and studying on the ecology of plant-pathogenic Streptomyces spp.

• BMB Reports
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• 제48권12호
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• pp.677-684
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• 2015

Cardiovascular function is regulated by the rhythmicity of circadian, infradian and ultradian clocks. Specific time scales of different cell types drive their functions: circadian gene regulation at hours scale, activation-inactivation cycles of ion channels at millisecond scales, the heart's beating rate at hundreds of millisecond scales, and low frequency autonomic signaling at cycles of tens of seconds. Heart rate and rhythm are modulated by a hierarchical clock system: autonomic signaling from the brain releases neurotransmitters from the vagus and sympathetic nerves to the heart's pacemaker cells and activate receptors on the cell. These receptors activating ultradian clock functions embedded within pacemaker cells include sarcoplasmic reticulum rhythmic spontaneous Ca²⁺ cycling, rhythmic ion channel current activation and inactivation, and rhythmic oscillatory mitochondria ATP production. Here we summarize the evidence that intrinsic pacemaker cell mechanisms are the end effector of the hierarchical brain-heart circadian clock system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.228-229
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• 2008

In this study, we propose an effective method to improve the clarity and period of the beat in a ring structure. Ring is an simplified model of a Korean bell, in which beating vibration and sound are very important features. An equivalent ring theory is applied and finite element analysis on the equivalent ring is performed to determine the condition of the asymmetric element for the clear and proper period beat. The clarity and the period of the beat are improved by attacking asymmetric mass and decreasing local thickness. Using the equivalent ring, the amount and position of the local variation for the required beat condition are determined and the results are verified by experiment.

• Journal of Chest Surgery
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• 제19권2호
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• pp.259-264
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• 1986

Broncholithiasis is defined as a cor9ition in which a concretion is present within a bronchus or a cavity in the lung communicating with a bronchus. The usual causes of broncholithiasis are known as tuberculosis, histoplasmosis, silicosis, aspirated calculi, and a few fungal infections. It is generally accepted that the constant motion created by respiration and beating of the heart may cause the peribronchial calcified lymph node to erode into the tracheobronchial tree and to form broncholith. After the analysis of our 6 cases of broncholithiasis which were treated surgically in the Department of Thoracic Surgery, Seoul National University Hospital from 1960 to December, 1985, we could suggest that intrinsic formation of calculi should be regarded as the pathogenesis of broncholithiasis in addition to the extrinsic formation of calculi.

• Journal of Chest Surgery
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• 제22권4호
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• pp.661-666
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• 1989

Congenital coronary arterial fistulae are the most prevalent hemodynamically significant congenital coronary artery malformations. Definition of congenital coronary arterial fistula is a direct communication between a coronary artery and the lumen of one of the four cardiac chambers or coronary sinus or SVC, pulmonary artery or pulmonary vein close to the heart. It is often associated with additional congenital or acquired heart disease. A 49 year old male patient was admitted with the chief complaints of anginal pain and exertional dyspnea for 9 months. He was diagnosed as the right coronary arterial fistula combined with right coronary arteriosclerotic stenosis and old inferior myocardial infarction by cardiac evaluation. The right coronary arterial fistula was communicated between the just distal portion of acute marginal branch and coronary sinus. The operative procedure was as followings; after suture ligation of fistula opening in the coronary sinus under beating heart, coronary arterial bypass grafting with saphenous vein was performed at the just proximal portion of the posterior descending branch under cardiopulmonary bypass. The postoperative course was uneventful and he was discharged without anginal pain at the 8th postoperative day.

• 펄프종이기술
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• 제30권2호
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• pp.24-29
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• 1998

This study was carried out in order to elucidate the deterioration mechanism of paper according to various sizing chemicals. No additive paper and four kinds of papers containing rosin-alum, alum only, alkylketene dimer(AKD)-cation polymer and cation polymer only were treated by UV light to study changes of water-resistant, optical and mechanical properties from the view points of natural deterioration of paper. Since rosin chemicals have UV absorption at the relatively long wavelength region, rosins are degraded to form hydrophilic groups such as carboxylic acid from their double bonds by UV treatments. These phenomena caused the decreasing of sizing degree and wetting time in case of rosin-sized paper, while the UV treatments brought about the slight increase of wetting time in rosin-free papers such as no additive, alum and kymene only paper owing to the auto-sizing effect. Optical properties were primarily influenced by sizing chemicals. Rosin-sized paper showed lower brightness after UV and near UV treatment because of its UV instability.