• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.145-145
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• 2012

반도체 집적회로의 집적도가 증가함에 따라 RC delay가 증가하며, 금속 배선의 spiking, electromigration 등의 문제로 인해 기존의 알루미늄 금속을 대체하기 위하여 구리를 배선재료로 사용하게 되었다. 하지만 구리는 실리콘 및 산화물 내에서 매우 빠른 확산도를 가지고 있으므로, 구리의 확산을 막아 줄 확산방지막이 필요로 하다. 이러한 확산방지막의 증착은, 소자의 크기가 작아짐에 따라 via/contact과 같은 고단차 구조에도 적용이 가능하도록 기존의 sputtering 증착 방법에서 이를 개선한 collimated sputter, long-throw sputter, ion-metal plasma 등의 방법으로 물리적인 증착법이 지속되어 왔지만, 근본적인 증착방법을 바꾸지 않는 한 한계에 도달하게 될 것이다. 원자층 증착법(ALD)은 CVD 증착법의 하나로, 소스와 반응물질을 주입하는 시간을 분리함으로써 증착하고자 하는 표면에서의 반응을 유도하여 원자층 단위로 원하는 박막을 얻을 수 있는 증착방법이다. 이를 이용하여 물리적 증기 증착법(PVD)보다 우수한 단차피복성과 함께 정교하게 증착두께를 컨트롤을 할 수 있다. 본 연구에서는 이러한 원자층 증착법을 이용하여 구리 배선을 위한 확산방지막으로 텅스텐질화막을 형성하였다. 텅스텐 질화막을 형성하기 위하여 금속-유기물 전구체와 함께 할라이드 계열인 WF6를 텅스텐 소스로 이용하였으며, 이에 대한 원자층 증착방법으로 이루어진 박막의 물성을 비교 평가하여 분석하였다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.1
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• pp.33-42
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• 2009

Recently, there have been many researches about anonymous credential systems for supporting the user anonymity. However, these systems only hold a high security level, even though they must be able to be applied to various application that might require access control, conditional traceability, etc. As new challenges to these systems, some researches that several entities store the link information that associates identities and pseudonyms each other have been performed. In this paper, based on the oblivious transfer, we suggest a new pseudonym protocol that solves the pseudonym exhaustion problem which the original pseudonym retrieval protocol suffers from. By using the universal re-encryption and one-way function, we can also archive other requirements like the pseudonym unlinkability from the outside.

• Journal of the Daesoon Academy of Sciences
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• v.19
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• pp.193-211
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• 2005

Korean religionist have actively participated in the movements of national security and peace, human rights and dignity, freedom and equal rights, and other social issues. Recently, either progressive or conservative religionists have strongly shown their different approaches in solving social issues, i.e., national security and peace in connection of 'national security law.' A few religious leaders' public views have been misused by some politicians. It is important for both the religionists and journalists in religious newspapers how to bring a harmonious resolution among the people who are either in conservatism or in progressivism. Social participation of religionists is both to respond to the timely situation of civil society and to realize freedom, equality, and peace to the society. Although the principle of the separation of religion and state was established to secure both the right of politics and the freedom of beliefs, political groups have either utilized or suppressed religions. Some politicians have also wrongly applied separation of religion and state by excluding religious aspects in public schools. Religionists and journalists of the religious newspapers should not provide one-sided prejudice but to provide objective information and its righteous analysis to guide people in the right direction to solve social problems. Also, religious newspapers should open a field of discussion how to resolve some issues between the 'national security law' and freedom.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.8-10
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• 2023

삼킴장애는 음식물이 입에서 식도로 가지않고 걸리거나 기도(Trachea)로 흡입되는 문제를 갖는 상태이다. 특히 노인이나 신경계 질환을 앓는 환자의 경우 기도로 흡입된 음식덩이가 폐렴을 일으키고 결국에는 사망으로 이어지기에 적절한 치료와 관리가 요구된다. 보통 영상으로 판단할 수 있는 삼킴단계는 구강준비단계(Oral Preparatory Phase), 구강단계(Oral Phase), 인두단계(Pharyngeal Phase), 식도단계(Esophageal Phase) 4가지로 분류하고 삼킴장애는 침습(Penetration)과 흡인(Aspiration)으로 크게 2가지로 분류한다. 본 논문에서는 이러한 6가지 클래스를 가지는 삼킴장애 환자 비디오 파일을 라벨링하기 위한 웹 애플리케이션을 제안한다. 이를 구현하기 위해서 대용량 멀티프레임 이미지를 수신해서 분리하여 저장하도록 개발하였다. 또한 음식덩이를 정교하게 분할할 수 있도록 GrabCut 알고리즘을 적용하여 라벨링할 수 있도록 하였다. 차후 라벨러와 전문의 간의 협업이 가능하도록 라벨링 데이터의 상태를 관리할 수 있도록 개발하고자 한다.

• Management & Information Systems Review
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• v.34 no.4
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• pp.15-29
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• 2015

This study aims to empirically analyze the relationship between management ownership and corporate performance and stock returns indicates the ownership structure of the company to target the listed companies in China over the past five years from 2010 to 2014. The empirical results are as follows: Management ownership gave an impact on stock returns, especially high-stakes management ownership showed significant positive effect with the stock returns. But management ownership don't have significant positive effect with ROA. The contribution of this study is as follows. Chinese companies have the efficiency of the management through the separation of ownership and management in accordance with the changes realized in capitalism. And this study is reflecting the fact of China using the Chinese data. This study has limitations of that. Management ownership measurement of governance structure don't expand the range, and measurement of governance structure is just one. The following studies are expected to be more sophisticated by comparison of countries.

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.385-393
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• 1997

다세포 생물에서 몸의 효율적 생존을 위한 각 기관의 homeostasis는 세포 증식과 사망에 의해 조절된다. 따라서, apoptosis라 명명된 세포사망은 정교한 기전에 의한 능동적이고 자발적인 사망기전으로써 몸의 정상적 유지를 위한 필수적인 현상이다. 발생기 세포나 신경세포 또는 흉선세포 분화 동안 과다한 세포의 제거가 apoptosis의 대표적인 예이며, 각종 호르몬에 의해 그 기능이 조절되는 난소세포에서도 apoptosis가 활발히 일어난다. Rat난소에는 태어날 때 수십 만개의 난포를 지니고 있는데, 이 중 단지 1%만이 배란에 사용되어질 뿐이고 나머지는 모두 사망하게 된다. 이러한 난포사망은 난소의 적절한 세포 수를 유지하기 위한 필수적 과정이며, 인위적으로 apoptosis를 억제하는 유전자인 bcl-2를 과다 발현시키면 난소암이 발생하는 연구결과가 이를 입증해주고 있다. 이처럼 중요한 난포 사망기전은 apoptosis라는 개념이 정립되면서 최근 들어 점차 그 연구가 활발해지고 있다. Apoptosis의 특징 중 뚜렷한 점은 DNA가 일정한 간격으로(180∼200 bp)잘려지는 DNA fragmentation현상으로, 이를 이용하여 DNA3'-end 부위에 방사선동위원소를 label한 후 이를 전기영동으로 분리하면 apoptosis를 손쉽게 측정할 수 있다. 난소의 기능은 시상하부호르몬인 LH와 FSH 뿐만 아니라 난소에서 분비되는 각종 난소국부호르몬들에 의해 조절된다. 특정한 발육단계의 난포는 특정한 호르몬에 의해 그 기능을 조절 받는데, 이러한 난소기능 조절기작은 매우 복잡한 경로를 지니고 있다. 이러한 복잡한 기작으로 인해 초기 연구에서첨 생체 내에서 밝히려는 연구 시도는 어려움에 부딪치게 되었다. 생체내 실험은 난소가 다양한 발육단계의 난포를 동시에 지니고 있어 특정한 발육단계의 난포 사망기전을 연구하기 어렵다. 또한 난포는 생체 내에서 다양한 호르몬을 동시에 분비하기 때문에 특정한 난소국부호르몬이 사망기전에 미치는 영향을 조사하기 힘든 점이 있다. 최근 들어 난포체외배양이 다양하게 개발되면서, 이러한 어려운 점을 극복할 수 있게 되었다. 본 논문은 각 발육단계의 난포를 절단해 체외배양하면서, apoptosis DNA 절단 현상을 이용하여 각종 난소국부 호르몬들이 난포발육단계별로 사망기전에 미치는 영향을 요약해 보였다. 난포는 발육하면서 점차 복잡한 호르몬 경로를 생존을 위해 필요로 한다. Prevulatory난포생존에 필요한 난소국부호르몬들은 early antral 단계의 난포에서는 그 미치는 영향이 감소되다가 preantral단계의 난포에서는 영향을 전혀 미치지 못했다. 단지 예외는 cGMP처리로써, 세포내 cGMP수준을 일정하게 유지시켜주는 것이 난포발육단계에 무관하게 생존에 중요한 인자로, 장래 연구는 난포 세포내의 cGMP수준을 조절하는 기작을 규명하는데 있을 것이다.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.303-314
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• 2020

Bottled water companies submit monthly hydrologic data including periodical environmental effects investigation, daily water production capacity, water production, water level, water chemistry (pH, EC, temperature) per hour and strictly manage groundwater by periodical analyses. Thus few problems concerning drawdown due to excess intake of groundwater take place. Nevertheless, bottled water companies are imprinted as a contribution to civil affairs resulted regarding groundwater near the companies. Therefore, a new method is required during water balance analysis in environmental effects evaluation, which should be compatible with the evaluation by hydrologic experts as well more accessible to non-experts. In this study, water level of surface water and recharge rate in subcatchment where water production wells are located were measured and monthly baseflow rates were separated from normal streams. Besides, recharge properties of groundwater and surface water in the same catchment area were estimated using analyses of oxygen and hydrogen isotopes in groundwater (production well), surface water, and rainfall.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.253-268
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• 2020

In this study, recharge rates are estimated using SWAT-K (a distributed hydrological model). The validity of the estimated recharge rates were evaluated by employing the baseflow separation method based on observed hydrological data. The exploitable groundwater is typically determined as the 10-year drought frequency recharge rate that is calculated by average recharge ratio multiplied by 10-year drought frequency precipitation. In practice, however, recharge rates typically decrease in line with precipitation; therefore, exploitable groundwater could be overestimated when average recharge rates are used without considering precipitation. To resolve this overestimation, exploitable groundwater was calculated by re-estimating recharge rates that consider precipitation intensity. By applying this method to the Uiwang, Gwacheon, and Seongnam sub-basins, the exploitable groundwater decreased by 55.5~77.6%, compared with recharge rates obtained using the existing method.

• Journal of the Korean Chemical Society
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• v.43 no.6
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• pp.699-706
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• 1999

The purpose of this study was to investigate high school students' conceptions and conceptual types on molecular kinetic theory of gases. Data was collected by a series of semi-structured and in-depth interviews, and has been analyzed. This study showed that the students came to science classes with various prior conceptions of many disciplinary topics. Their conceptual types of their prior knowledge were distinguished as superficial terms-speaking, partial sense-making, and causal sense-making by the degrees of organization and elaboration of conceptual networks. These conceptual types had influence on the ways students understand and think of science, a stability of their conceptions, a tendency to distinguish school science from everyday science, and building a meaning of concept in contexts. It was referred that the students didn't have proper understanding on the nature of scientific knowledge and had been limited their participations as active learners. Therefore, in order for students to experience conceptual change, they must have opportunities of manifesting their own thinking, taking part in discussions, and promoting their motivations and metacognition of knowing and learning science.

• Journal of Korea Water Resources Association
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• v.43 no.4
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• pp.367-381
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• 2010

Recent urbanization and abnormal weather have induced enormous changes in the characteristics of both runoff and pollutant occurrence. Thus, sophisticated watershed modeling of water quality is required. In order to manage non point sources in a watershed, quantitative analysis should be preliminarily performed. However, it is difficult to conduct quantitative analysis since complex natural phenomenon need to be reflected in the modeling. Also, travel time analysis for pollutants and separation of point and non point sources are not easy to carry out. The objective of this study is to quantify non point sources in watershed using soil and land use map and to make the full use of the results in managing non point sources. To do this, non point sources are quantified using a watershed model, SWAT (Soil and Water Assessment Tools). The result of study conform with result of National Institute of Environmental Research.