• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.1
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• pp.16-24
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• 1998

In this study, Ocean General Circulation Model (OGCM) has been developed as a counterpart of Atmospheric General Circulation (AGCM) for the study of coupled ocean-atmosphere climate system. The oceanic responses to given atmospheric boundary conditions have been investigated using the OGCM. In an integration carried out over 100 simulated years with climatological monthly mean data (EXP 1), most parts of the model reached a quasi-equilibrium climate reproducing many of the observed large-scale oceanic features remarkably well. Some observed narrow currents, however, such as North Equatorial Counter Current, were inevitably distorted due to the model's relatively coarse resolution. The seasonal changes in sea ice cover over the southern oceans around Antarctica were also simulated. In an experiment (EXP 2) under boundary condition of 10-year monthly data (1982-1991) from NCEP/NCAR Reanalysis Project model properly reproduced major oceanic changes during the period, including El Ni$\tilde{n}$os of 1982-1983 and 1986-87. During the ENSO periods, the experiment showed eastward expansion of warm surface waters and a negative vertical velocity anomalies along' the equator in response to expansion of westerly current velocity anomalies as westerly wind anomalies propagated eastward. Simulated anomalous distribution and the time behavior in response to El Ni$\tilde{n}$o events is consistent with that of the observations. These experiments showed that the model has an ability to reproduce major mean and anomalous oceanic features and can be effectively used for the study of ocean-atmosphere coupling system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.177-184
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• 2000

The effect of the buyancy and thermocapillarity for differnent aspect ratio of flow field on melt motion and mass transfer has been numerically investigated in magnetic Czochralski crystal growth of silicon. During the process of crystal growth, the melt depth of crucible reduces so the aspect ratio of flow field also reduces. Therefore the shape of magnetic field of the flow field changes and the flow pattern also changes significantly. Together with the melt flow which forms the Marangoni convection (or thermocapillary flow) that comes from the inside the flow field, a flow circulation is observed near the corner close both to the crucible wall and the free surface. Due to this circulation, buoyancy effect has been turned out to be local rather than global. As the aspect ratio decreases, the radial component of the magnetic field prevails compared with the axial component in the flow field. Under the influence of this magnetic field, the melt flow and the temperature distribution in a meridional plane tend to depend on the radial position. As the aspect ratio decreases, the temperature gradient near the edge of the crystal decreases yielding smaller thermocapillarity, and the oxygen concentration near the crystal and the oxygen incorporation rate also decrease.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.3
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• pp.129-138
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• 1988

In order to develop the design and operational criteria in sewage treatment by indirect aerating submerged biofilter, experimental investigations were performed for the reasonable oxygen supply and effecting factors of treatment efficiency. The experiments were executed for the up-flowing synthetic wastewater and aerated water in the submerged biofilter at $20^{\circ}C$. The obtained results are as follows: 1) Appropriate mean diameter of gravels was about 11mm. 2) $BOD_5$ loading rate based on biofilter volume was more reasonable than that on surface area of gravel for operational criteria. 3) To remove the influent $BOD_5$ more than 90%, $BOD_5$ loading rate must be less than $1.0kg-BOD_5/m^3{\cdot}d$ and circulating flowrate must be more than $189m^3/m^3{\cdot}d$. 4) Reaction rate coefficient $K_1$ is related to diameter of gravel and circulating flow rate based on biofilter volume.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.339-342
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• 2003

Sea level variations and sea surface circulations inthe Korean seas were observed by Topex/Poseidon altimeter data from 1993 through 1997. In sea level variations, the West and South Sea showed relatively high variations with comparison to the East Sea. Then, the northern and southern area in the West Sea showed the range of 20-30cm and 18-24cm, and the northern west of Jeju island and the southern west of Tsushima island in the South Sea showed the range of 15-20cm and 10-15cm, respectively. High variations in the West Sea was results to the inflow in sea surface of Yellow Sea Warm Current (YSWC) and bottom topography. Sea level variations in the South Sea was due to two branch currents (Jeju Warm Current and East Korea Warm Current) originated from Kuroshio Current (KC). In sea surface circulations, there existed remarkably three eddies circulations in the East Sea that are mainly connected with North Korea Cold Current (NKCC), East Korea Warm Current (EKWC) and Tushima Warm Current (TWC). Their eddies are caused basically to the influence of currents in sea surface circulations; Cyclone (0.03 cm/sec) in the Wonsan bay on shore with NKCC, and anticyclone (0.06 cm/sec) in the southwestern area of Ulleung island with EKWC, and cyclone (0.01 cm/set) in the northeastern area of Tushima island with TWC, respectively.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.162-165
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• 2006

The innominate artery aneurysm is an uncommon entity. A 36-year-old man was transferred to our hospital because of incidental finding of right superior mediastinal mass. He had a history of blunt chest trauma due to automobile accident 16 years earlier. Computed tomography scanning demonstrated 5-cm sized sacular aneurysm with thrombus at the innominate artery. The prosthetic bifurcated bypass grafting from the ascending aorta to the right common carotid artery and right subclavian artery was performed under the moderate hypothermic cardioplumonary bypass. We report a successful surgical treatment for a rare case of the innominate artery aneurysm.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.4
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• pp.353-358
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• 2002

In this paper, improved ZCS-PWM boost converter is proposed. The proposed converter eliminates additional conduction loss of a main switch by flowing circulating current oかy through an auxiliary switch. The operation modes of proposed converter are explained. And design procedure of resonant parameters is established. Experimental results are presented to verify the theoretic analysis of the proposed converter.

• Annual Conference on Human and Language Technology
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• 1994.11a
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• pp.326-332
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• 1994

본 연구에서는 중사전 규모의 현대국어사전에서 약 5,000 개의 표제항목의 뜻풀이 8,000여 항에 사용된 어휘를 분석한 결과를 제시하였다. 분석 결과 명사류의 의미구조에서 최상위계층에 속하는 것들이 사전의 뜻풀이에 자주 사용됨을 확인할 수 있었고, 아울러 뜻풀이에 사용되는 단어들이 어느 정도 통제된 상태임을 알 수 있었다. 그러나 표제항목과 뜻풀이에 사용된 단어들 사이의 관계만을 바탕으로 해서는 의미망을 구축하기 어려웠는데, 그것은 국어사전에서의 뜻풀이가 지니고 있는 구조적 문제에서 기인하는 것이다. 즉 일부 한자어의 경우에는 명사로 정의되지 않으며, 그 결과 표제명사와 뜻풀이에 사용된 명사 사이의 관계를 바탕으로 한 의미망의 구축에 포함되지 않는 것이다. 또한 순환적 뜻풀이의 경우 역시 의미망 구축에 장애요소로 작용함을 밝혔다.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.536-538
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• 2009

현재 세계 각 국은 폐차에 의한 환경오염을 줄이기 위하여 규제를 강화하고 있으며 특히 EU(European Union)에서는 현재 85%에 머무르고 있는 재활용율을 2015년까지 95%로 올릴 것을 요구하고 있다. 이에 발맞추어 2007년 우리나라도 "전기전자제품 및 자동차의 자원순환에 관한 법률"을 제정하였다. 자동차 중량의 75%를 차지하는 철은 비교적 높은 재활용율을 보이고 있으나 나머지 25%를 구성하는 플라스틱, 유리 고무 등의 비금속류와 구리, 니켈 알루미늄 등의 비철금속류는 재활용율이 이에 미치지 못하고 있다. 본 논문에서는 자동차에서 많이 사용되는 대표적인 비철금속인 구리에 대하여 재활용의 현주소를 점검하고 앞으로의 개선책을 논의하고자 한다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.10a
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• pp.117-118
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• 2016

염증류장치의 효율 향상 및 조업 편의성을 제고하기 위하여 염회수용기를 하부 플랜지에 삽입하여 일체형 증류장치를 개발하기 위한 연구를 수행하였다. 플랜지-염회수용기 일체형 진공증류장치는 응축조에 염회수용기를 따로 두지 않고, 하부 플랜지가 염회수 용기의 역할을 할 수 있도록 함으로써 냉각 기체와 접촉면이 증가하므로 냉각 효율을 높였고, 냉각 플랜지를 상하 회전하여 회수된 염을 탈착함으로써 염의 재순환 작업이 매우 편리할 것으로 판단된다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.115-125
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• 1998

딸기는 숙근성 초본이며 내한성이 강한 과채류로 노지면적은 계속 감소하여 1996년에 907 ha이나, 시설재배면적은 계속 증가하여 6236 ha를 나타내고 있다. 이와 같이 딸기는 이제 대부분의 생산량이 시설 내에서 생산되고 있다. 유럽과 일본 등에서 딸기의 양액 재배 면적은 급속히 증가하고 있는데 비해 국내에서의 딸기 양액재배 면적은 극히 적은 면적에 지나지 않지만, 앞으로 생산성과 품질의 증가가 기대되는 작물이기 때문에 재배 면적의 증가가 기대되는 채소작물 중 하나이다. (중략)