• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.2
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• pp.115-127
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• 1991

In this paper. we dIscussed wIth the ISDN numberIng system of Korea 2digIt of NDC(National Destination Code)is assigned to the common carrier indenttification and an other the service network identification code as conbining the flIst and second dIgIt. The last ot NDC is applicable to for each area code. Resulty. we become 10 digit number for toll system vice 7 digit for local numbering. It is satisfactory to CCITT recommandtion and also. We has been suggested that existing network the mobile. pagget, FAX, TELEX and public networks are able to be connetcted to the ISDN. Near the 1994. we guess that it is fully occupied with 7 digit number to the metropolitan area to solve this problem, after divide to 3 part provincial area southern. nothem and mid-Korea. We suggested that special number system are reorganized with the new and existing service numbers plan. Although, we don't deal with the SA of ISDN numbering systems. Resultly, know that we are to design efficiently number system as 3 digit code for ISDN/NSN.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.515-517
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• 2008

현재 가동 중인 원자적발전소 계측제어설비의 전원공급기를 살펴보면 인버터 또는 별도의 교류를 입력전원으로 사용한다. 직류 전원공급기들은 설비의 중요도예 따라 이중화로 구성된 설비도 있고 그렇지 않은 기기나 설비도 있다. 이중화로 구성된 전원공급기라 해도 교류 입력전원이 동일하다면 교류 입력이 상실될 때 이중화로 구성된 직류전원도 상실되어 관련계통의 가동이 정지된다. 이러한 문제점을 해결하기 위해서는 각기 다른 교류입력전원으로 동작되는 이중화전원공급기로 구성되는 것이 가장 바람직하다. 본 연구개발의 목적은 두 종의 설비에 소요되는 3종의 직류전원 공급기를 원자력 안정성등급으로 국산화하는 연구이다. 기존 제품들은 3종 모두 리니어 방식의 제품이지만, 방사선감시 계통 현장제어기의 5V로직 전원공급기와 공정제어계통 전원공급자는 전력변환효율이 높고 소형, 정량화가 가능한 SMPS(Switched Mode Power Supply) 방식으로 개발하였다. 방사선감시계통 현장제어기의 PCA(Printed Circuit Assembly) 저전압공급기는 다양한 종류의 출력전압과 저 전류형이므로 안정성 면에서 동일한 형식의 리니어 방식으로 개발하였으며 3종류 모두 출력용량을 20% 이상 향상시켰다. 또한, 논문을 통해 SMPS 방식의 전원공급기의 핵심 부품인 Control Module을 Hybrid IC형으로 자체 설계하여 성능이 우수한 제품을 지속적으로 생산할 수 있는 기틀을 마련하고자 한다.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4267-4273
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• 2016

Previous studies suggested that dithio-carbamates are potent apoptosis and anti-apoptosis inducing agents in various cancer cells. Here, the anti-proliferative and apoptosis inducing effects of a new derivative (2-NDC) from the dithio-carbamate family was examined in human leukemia K562 cells. We use thiazolyl blue tetrazolium bromide (MTT) to measure viability and cell growth inhibition. The 2-NDC showed effects on viability in a dose and time-dependent manner, inhibiting proliferation at concentrations of $10-30{\mu}M$ after 24-48 hours of treatment and increasing values after 72 hours at $40-120{\mu}M$. The cytotoxic effect of the compound was calculated with an $IC_{50}$ of $30{\mu}M$ after 24-hour. Apoptosis induction was confirmed by acridine orange-ethidium bromide (AO/EtBr) staining, DNA fragmentation assay, flow cytometric assessment and also caspase-3 activation assay. Furthermore, enzymes level such as superoxide dismutase (SOD) and catalase (CAT) involved in oxidative stress were evaluated. The results of this study demonstrated insignificant increase of intracellular ROS levels for 24 hours and reduction after 48-72 hours. In addition to reduction of intracellular thiol, caspase-3 like activity was also decreased in a time-dependent manner in cells treated with 2-NDC. Thus 2-NDC can be considered as a good candidate for further pharmaceutical evaluations.

• Polymer(Korea)
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• v.35 no.6
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• pp.599-604
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• 2011

The PET-PEN copolymers have been synthesized and the effect of their morphology on the physical properties of polyester flexible substrate was investigated. It was found that the block sequence of synthesized copolymer was varied depending upon DMT/NDC ratio in polymerization. Higher PET-PEN and PEN block sequence in polyester copolymer resulted in the increase of glass transition temperature and it caused the enhancement of dimensional stability as a polyester flexible substrate. The highest coefficient of thermal expansion(CTE) was obtained when DMT/NDC ratio is 50/50. Synthesized PET-PEN copolymer seems to be acceptable as a flexible substrate since it shows that their optical transmittance at 550 nm is over 80% and thermal weight loss at $280^{\circ}C$ for 1 hr is less than 0.4 wt%.

• Journal of Korean Library and Information Science Society
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• v.43 no.4
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• pp.5-22
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• 2012

The purpose of this study aims to provide possible suggestions for the improvement of KDC 5th ed. in Jurisprudence Field. The research methods are as follows. First, to analyze academic fields in Jurisprudence, the contents of Jurisprudence introductory books are investigated. Second, to find out the problem of KDC Jurisprudence field, comparative analysis is done on the three classification schemes - KDC, DDC and NDC. Third, curriculum of domestic law schools are reflected. If above suggestions are adopted, effective literature classification scheme which is suited to domestic circumstances will be certainly prepared.

• Journal of Korean Library and Information Science Society
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• v.39 no.2
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• pp.249-266
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• 2008

This study investigated general problems concerning the subject Chemical Engineering in the KDC(Korean Decimal Classification) 4th edition based on the comparative analysis with DDC, NDC, and Disciplinary Classification System of Korean Research Foundation, and suggested on some ideas for the improvements of them. The subject of chemical Engineering in the KDC 4th edition had to be improved to use current terminology, to choose appropriate headings, and to subdivide the subjects more to introduce new topics.

• Journal of Korean Library and Information Science Society
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• v.41 no.4
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• pp.5-33
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• 2010

This study is intended to present methods improving the classification system of KDC education fields after comparing and analyzing the academic system of education, classification system of KDC, NDC, DDC and LCC, and that of the research field classification system of National Research Foundation of Korea. The results of the analysis have revealed that it is required to improve and correct the KDC 5th edition of education including the addition of classification items that reflect the trend of academic development, proper development in the rank classification terms of education detailed fields, addition of detailed subjects, errors of classification symbols and omission of correlative indexes in the classification items. This study has proposed improved methods to solve those problems.

• Journal of the Korean Society for Library and Information Science
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• v.42 no.4
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• pp.291-310
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• 2008

The U.S. Library of Congress proposal to change the subject heading of Tok Island(in Korea called Dokdo) to Liancourt Rocks was controversial. Therefore the status of Dokdo, national notation(Dokdo or Tokdo), and international notation used to identify the island were examined. In this examination, Tok Island's classification in the Korea Decimal Classification(KDC), Library of Congress Classification(LCC), and Nippon Decimal Classification(NDC) were compared and analysed, and a proposal for the role of libraries in the future was given.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.22 no.3
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• pp.207-228
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• 2011

The notes of the classification system are to improve the accuracy and consistency of classification by providing useful information on classification numbers and items. Even though, several notes are used in KDC, they are not enough to keep up with rapidly developing and expanding knowledge of nowadays. The purpose of this study is to suggest appropriate types and improvements of the notes in KDC 5th edition. In order to achieve these purposes, transition of notes in KDC was analyzed. Notes of DDC 23rd edition, NDC new 9th edition, and KDC 5th edition were also analyzed. Based upon these comparison and analysis, problem and improvement of notes in KDC were suggested.

• Journal of the Korean earth science society
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• v.43 no.1
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• pp.41-59
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• 2022

In accordance with the enactment of 'the Paris Agreement' in 2015 and 'the Framework Act on Carbon Neutrality and Green Growth for Response to the Climate Crisis' in 2021, each local government has set appropriate reduction target of greenhouse gas to achieve the nationally determined contribution (NDC, the reduction target of 40% compared to 2018) of greenhouse gas (GHG) emissions in 2030. In this study, the current distribution of GHG emissions was analyzed in a time series centered on the Chungbuk region for the period from 1990 to 2018, with the aim of reducing GHG emissions in Chungbuk by 2030 based on the 2030 NDC and scenario. In addition, the prospected reduction by 2030 was estimated considering the projected emissions according to Busines As Usual in order to achieve the target reduction of GHG emissions. Our results showed that GHG emissions in Chungbuk and Korea have been increasing since 1990 owing to population and economic growth. GHG emissions in 2018 in Chungbuk were very low (3.9 %) relative to the national value. Moreover, emissions from fuel combustion, such as cement and lime production, manufacturing and construction industries, and transportation industries, were the main sources. Furthermore, the 2030 target of GHG emission reduction in Chungbuk was set at 40.2% relative to the 2018 value, in accordance with the 2030 NDC and 2050 carbon-zero national scenario. Therefore, when projected emissions were considered, the prospected reduction to achieve the target reduction of GHG emissions was estimated to be 46.8% relative to 2018. The above results highlight the importance of meeting the prospected reduction of GHG emissions through reduction means in each sector to achieve the national and local GHG reduction target. In addition, to achieve the 2030 NDC and 2050 carbon zero, the country and each local government, including Chungbuk, need to estimate projected emissions by year, determine reduction targets and prospect reductions every year, and prepare specific means to reduce GHG emissions.