• Proceedings of the KAN Conference
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• 2004.11a
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• pp.57-63
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• 2004

• The Bulletin of The Korean Astronomical Society
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• v.11
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• pp.9.3-10
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• 1986

• Proceedings of the KSRS Conference
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• v.2
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• pp.993-996
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• 2006

NOAA operational bulk SST product (Reynolds et al, 2002) is very popular global SST data sets and is extensively used for various studies. However, the original time resolution is weekly and relatively large. On the other hand, there exist many new global SST data sets at present. In this study, we compare many global SST data sets including NOAA operational bulk SST product, CAOS OI SST product, Microwave Optimum Interpolation (MWOI) SST, Real Time Global (RTG) SST and JMA merged satellite and in situ Global Daily (MGD) SST.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2471-2476
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• 2007

A series of titanium complexes containing terdentate β-ketoiminate ligands were found to be efficient for the ring-opening polymerization of ε-caprolactone (ε-CL), producing poly(ε-caprolactone) (PCL) with bimodal distribution. Steric factors imposed by methyl substituents on the back bone of the alkoxy group affected significantly the polymerization rate and physical properties of the resulting PCL. Intra- and intermolecular transesterifications rather than disproportional rearrangements were responsible for the bimodal behavior and for the change in the molecular weight (Mw). Dilution with toluene reduced yield, and lowered polydispersity (PDI) and Mw of PCL, while the catalytic activities of the dimeric complex, [Ti(Oi-Pr)2(N-alkoxy-β- ketoiminate)]2 and Ti(Oi-Pr)4 were not sensitive to the added solvent. The dimeric complex showed living character, while other catalysts suffered from chain termination reactions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.385-388
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• 1997

As the environmental regulations become stricter, new machining technologies are being developed which takes envi ronmenta 1 aspects into account . Since cut t ing oi I has some impact on environment. many researches are being carried out to minimize the use of cutting oi I. The methods for minimizing cutting oil usage includes the following techniques: I ) Cooling of tools and work piece. 2) Useage of compressed cooling air for the removal of chip. 3) Minimal useage of environment-friendly vegetable cutt:ngoiI for lubrication between chip and tools. Since the turning machine is continuous, tools are under constant thermal load and tool wear increases as the lubricative performance degrades. Also surface roughnesses have a direct influence on turning. In order to examine the characteristics of turningmachining, this work investigates experimentally the degree of tool wear and characteristics of surface roughness in relation to machining conditions, supply methods, and cooling methods.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.6
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• pp.259-263
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• 2001

The continuum model of transient point defect dynamics to predict the concentrations of interstitial and vacancy is established by estimating expressions for the thermophysical properties of intrinsic point defects. And the point defect distribution in a Czochralski-grown 200 mm silicon crystal and the location of oxidation-induced stacking fault ring(OiSF-ring) created during the cooling of crystals are calculated by using the numerical analysis. The purpose of this paper is to show that his approach lead to predictions that are consistent with experimental results. Predicted point defect distributions by transient point defect dynamic analysis are in good qualitative agreement with experimental data under widely and abruptly varying crystal pull rates when correlated with the position of the OiSF-ring .

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.360-366
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• 2009

AQUA/AMSR-E 인공위성 자료를 활용하여 3차원 최적내삽 해수면온도 합성장을 생산하였고 시간평균장과 비교하여 문제점과 한계점을 기술하였다. 3-D SST 합성장은 북태평양 중앙부에서 전체적으로 $0.05^{\circ}C$ 이하의 작은 오차를 보였으나, 위성 결측이 있는 연안에서는 $0.4^{\circ}C$ 이상의 비교적 큰 오차를 유발하였다. 강한 강수나 구름으로 인한 결측이 있는 부분에서는 $0.1\sim0.15^{\circ}C$에 달하는 오차를 보였다. 시간평균장과 비교한 결과, 구름 부근의 화소에서는 해수면온도를 낮게 계산하는 경향이 있었으며, 해수면온도의 공간적 구배를 감소시키는 평활화가 전체적으로 나타났다. 저위도에서 OI SST는 실제 해수면온도에는 없는 불연속성을 만드는 경향이 있었고, 이는 OI 과정에서 사용한 윈도우의 크기와 해양 현상의 수평 규모가 위도에 따라 변화하는데서 기인하였다. 현상의 공간 규모의 척도인 로스비 내부 변형 반경은 북태평양에서 O(1) 정도로 위도에 따른 공간적 변화가 큰 것으로 나타났다. 본 연구는 SST 합성장 생산 과정에 위도와 해수의 수직적 밀도 구조와 밀접한 관련이 있는 해양 현상의 수평적 규모의 시공간적 변동 특성을 고려해야 함을 제시한다.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.209-218
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• 2012

In this study, suitable types and measures of Wildlife Crossing Structures (WCS) for mammals of Korea were analyzed to suggest basic information for design guidelines of WCS. In order to find the types and measures, we conducted field surveys on 79 WCS and literature reviews on 159 WCS. The results of our study were as follows; Small-medium sized carnivores usually use all measures of wildlife underpass, meanwhile large sized herbivores as water deer need lager measures than 0.7 Openness Index(OI). Furthermore, we found that wildlife overpasses were usually used at the measure of 6.8 m width by every mammal. Therefore, we concluded that the proper measures should be lager than 0.7 OI for underpass and 7 m width for overpass.

• Journal of Audiology & Otology
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• v.25 no.4
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• pp.230-234
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• 2021

Otosclerosis, a hereditary disorder characterized by disordered resorption and deposition of bone, results in progressive hearing loss. Osteogenesis imperfecta (OI) is a genetic disorder characterized by recurrent fractures, blue sclera, and varying degrees of hearing impairment; and is a known risk factor for otosclerosis. After adolescence, the risk of fracture decreases, reducing the need for follow-up in OI. However, otosclerosis is a progressive disorder. In this report, we discuss two cases of familial otosclerosis with different clinical features. We hypothesize that the difference in hearing level correlates with the difference in computed tomography findings. The mother, whose case was considered severe, was prescribed hearing aids, while the daughter, who had normal hearing level, was regularly followed up.

• Korean Journal of Audiology
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• v.25 no.4
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• pp.230-234
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• 2021

Otosclerosis, a hereditary disorder characterized by disordered resorption and deposition of bone, results in progressive hearing loss. Osteogenesis imperfecta (OI) is a genetic disorder characterized by recurrent fractures, blue sclera, and varying degrees of hearing impairment; and is a known risk factor for otosclerosis. After adolescence, the risk of fracture decreases, reducing the need for follow-up in OI. However, otosclerosis is a progressive disorder. In this report, we discuss two cases of familial otosclerosis with different clinical features. We hypothesize that the difference in hearing level correlates with the difference in computed tomography findings. The mother, whose case was considered severe, was prescribed hearing aids, while the daughter, who had normal hearing level, was regularly followed up.