• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.188-192
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• 2015

Gemological and spectroscopic properties of HPHT synthetic diamonds from New Diamond Technology (NDT) company in St. Petersburg (Russia) were examined. Their color (colorless, near-colorless with some boron and Fancy blue with high boron content) and clarity ($VVS-SI_1$) grades were comparable to those of top natural diamonds. NDT synthetic diamonds fluoresced and phosphoresced blue or orange under SWUV light. Photoluminescence spectra revealed H3 center with very small intensity and NV centers. The intensity of H3 in NDT synthetic diamond has very weak in comparison with natural one. Using a combination of gemological and spectroscopic tests, gem-quality synthetic diamonds from NDT can be distinguished from natural diamonds of similar quality.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1345-1355
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• 2000

The main route of exposure of the human population to polychlorinated dibenzop-dioxins(PCDDs) and polychlorinated dibenzofurans(PCDFs) is through the diet. However in Korea, there are few studies on PCDDs/PCDFs levels in environmental samples and foods. The purpose of this study is to analyze concentration of PCDDs/PCDFs in Korean retail foods and to estimate dietary daily intake of them. 9 samples from animal food and 10 samples from plant food were analysed for PCDDs/PCDFs. Concentrations of PCDDs/PCDFs ranged from 0.02(milk) to 5.39(anchovy)pg/g. TEQ levels appeared in order of fish/shellfish, meat, vegetable, cereal, fruit and milk, and these values ranged from 0.0008 to 0.3153pgTEQ/g. The daily intake of PCDDs/PCDFs via food was calculated to be about 37.7pgTEQ/day and these values are equivalent to 0.75 pgTEQ/kg b.w./day, under consideration of 50kg for body weight. The daily intake of PCDDs/PCDFs via food was lower than that in other countries. From these results, it is important to note that fish/shellfish intake is one of the main sources of PCDDs/PCDFs exposure in Korea.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.546-549
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• 2011

• Proceedings of the Optical Society of Korea Conference
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• 1990.07a
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• pp.133-138
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• 1990

점접촉 MIM (Metal-Insulator-Metal) 다이오드는 레이저 광속의 검출기, 고조파 발생기 및 믹서로 사용되며, 그 검출범위가 수십 THz의 주파수 영역까지 가능하다. 이러한 MIM 다이오드의 여러사기 변수들에 대한 감응도를 측정하였으며, 이들의 특성을 조사하기 위한 관원으로는 10P(36) line의 CO2 레이저 광속을 이용했다. 또한 제작된 점접촉 MIM 다이오드를 이용하여 두 CO2레이저 사이의 주파수 차이에 의한 맥놀이 주파수를 측정하였다. 그리고 MIM 다이오드에서 발견된 초퍼의 초핑 주파수에 의한 비선형 현상을 논하였다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.197-198
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• 2002

1977년 네덜란드에서 배출가스 및 집진재에서 다이옥신류를 검출해낸 이후 다이옥신 문제는 현재까지 전 세계적으로 중요한 환경문제로 인식되어 많은 연구가 진행되고 있다 우리나라에서도 '96년 국립환경연구원의 몇몇 쓰레기소각장 배출가스 중 다이옥신농도 발표 및 '97년 6월 환경부의 전국 소각장 다이옥신 배출실태조사결과가 발표되면서 시급히 해결해야 할 중요한 환경문제의 하나로 국민적 관심을 끌기 시작하였다. (중략)

• Journal of the Korean Chemical Society
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• v.50 no.4
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• pp.346-350
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• 2006

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1655-1657
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• 2000

본 논문에서는 세라믹 다이어프램식 압력센서를 설계하기 전에 세라믹 다이어프램의 변위에 대한 최적 조건을 확립하기 위해 세라믹의 기계적 특성, 다이어프램의 두께와 직경 등을 변화시키면서 중심부와 변곡점 부근에서 압력에 대한 다이어프램의 변위를 시뮬레이션 하였다.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.86-87
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• 2003

단일 소자로 외부의 제어회로를 통해 여러 파장으로 발진파장을 제어할 수 있는 파장가변 레이저 다이오드는 고정된 파장으로 발진하는 레이저 다이오드에 비해 여러 경제적 이점을 가지며 보다 유연한 광 네트워크의 구성이 가능하게 한다. 이러한 이유로 현재까지 다양한 구조의 파장가변 레이저 다이오드가 제안되고 개발되어 왔다. 본 논문에서는 새로운 구조의 광대역 파장가변 레이저 다이오드를 제안하였다. (중략)

• Journal of Korean Philosophical Society
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• v.141
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• pp.63-84
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• 2017

In the twentieth century Anscombe's 1958 article "Modern Moral Philosophy" argued that duty-based conceptions of morality are conceptually incoherent for they are based on the idea of a "law without a lawgiver". Concepts such as "morally ought", "morally obligated", and "morally right" require a legislator as the source of moral authority. In the past God occupied the role, but systems that dispense with God are lacking the proper foundation for meaningful employment of those concepts. Aristotle's virtue ethics can do so without appealing to any such lawgiver, and ground morality in the well being of human moral agents. Therefore Anscombe recommends a return to the eudaimonistic ethical theories of the ancients as secular approaches. Eudaimonia is a central concept in Aristotelian ethics, along with the terms "aret?"(translated as virtue or excellence) and "phronesis"(translated as practical wisdom). In Aristotle's works, eudaimonia was used as the term for the highest human good, and so it is the aim of practical philosophy to consider what it really is and how it can be achieved. Eudaimonia is a Greek word commonly translated as well-being, happiness, welfare or "human flourishing". As Aristotle points out, saying that eudaimon life is a life which is objectively desirable, and means living well. Everyone wants to be eudaimon. And everyone agrees that being eudaimon is related to faring well and to an individual's well being. But the really difficult question is to specify just what sort of activities enable one to live well. Aristotle says that the eudaimon life is one of "virtuous activity in accordance with reason," this is a necessary condition of eudaimonia, the pleasure accompanied by virtuous activities is a sufficient condition. Hence we have a more accurate translation of eudaimonia with a review the practical meaning of eudaimonia, and the correlation between eudaimonia and arete, pleasure.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.3
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• pp.309-316
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• 2015

A state-based peridynamic model is able to describe a general constitutive model from the standard continuum theory. The response of a material at a point is dependent on the deformation of all bonds connected to the point within the nonlocal horizon region. Therefore, the state-based peridynamic model permits both the volume and shear changes of the material which is promising to reproduce the complicated dynamic brittle fracture phenomena, such as crack branching, secondary cracks, cascade cracks, crack coalescence, etc. In this paper, the two-dimensional state-based peridynamic model for a linear elastic plane stress solid is employed. The damage model incorporates the energy release rate and the peridynamic energy potential. For brittle glass materials, the impact of the crack-parallel compressive stress waves on the crack branching pattern is investigated. The peridynamic solution for this problem captures the main features, observed experimentally, of dynamic crack propagation and branching. Cascade cracks under strong tensile loading and secondary cracks are also well reproduced with the state-based peridynamic simulations.