• Electronic Materials Letters
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• 제14권6호
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• pp.712-717
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• 2018

In this letter, we have introduced copper chloride ($CuCl_2$) as an additive in the $CH_3NH_3PbI_3$ precursor solution to improve the surface morphology and crystallinity of $CH_3NH_3PbI_3$ films in a single solvent system. Our optimized perovskite solar cells (PSCs) with 2.5 mol% $CuCl_2$ additive showed best power conversion efficiency (PCE) of 15.22%. The PCE of the PSCs fabricated by $CuCl_2$ (2.5 mol%) additive engineering was 56% higher than the PSC fabricated with pristine $CH_3NH_3PbI_3$.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.924-927
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• 2009

IT-SoC의 성능 향상과 개발기간 단축을 위한 IP 재사용 (reuse) 기술은 SoC 산업이 본격적으로 성장하기 위한 필수 요소이다. 이러한 IP 기술은 수요기업의 요구에 부응하는 적합한 사양을 결정하고 표준화 하는 일이 매우 중요하며, 무엇보다도 수입에 의존하지 않는 국산 기술의 개발이 중요하다. 본 고에서는 반도체 설계의 지식재산권화의 필요성과 그 재사용에 대한 중요성에 대하여 분석하고 논의한다. 특별히, 미국의 CAST 사에서 수입하여 사용하고 있는 암호화 IP를 예를 들어 문제점을 분석한다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.415-418
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• 2016

IT융합 교육의 핵심은 SW 교육을 통해서 이루어지고 SW 교육의 목적은 CT(Computational Thinking)을 향상하는데 초점이 맞추어 지고 있다. 본 논문은 Unity3D 프로그램을 활용한 소프트웨어 교육이 학습자의 컴퓨팅 사고력과 학습 흥미에 미치는 영향을 조사하기 위하여 실험집단과 통제집단을 구성하고 학습자들의 동질성 여부를 확인한 후 실험집단에 Unity3D를 활용한 소프트웨어 교육을 실시하여 학습자의 컴퓨팅 사고력과 학습 흥미에 어떠한 영향을 미치는지 측정하였다. Unity3D를 활용한 프로그래밍 교육이 EPL(Educational Programming Language)을 활용한 블록 코딩 소프트웨어 교육과 일반 텍스트 언어인 C언어, Phython, Java와 같은 프로그래밍 언어의 중간 단계로서의 적합성을 제안한다.

• 분석과학
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• 제34권1호
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• pp.9-16
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• 2021

In the group of commonly prescribed β-blocker drugs, one of the enantiomers is generally relatively more active than the others. This study aims to develop a technique for the chiral analysis of select β-blockers based on proton nuclear magnetic resonance (1H-NMR) spectrometry. (S)-2-Tert-butyl-2-methyl-1,3-benzodioxole-4-carboxylic acid ((S)-TBMB) was synthesized and utilized as a chiral derivatizing agent. Pure β-blocker enantiomers were isolated from racemates by semi-preparative liquid chromatography prior to derivatization. The reaction time and concentration of (S)-TBMB were controlled to improve the derivatization procedure. No racemization was found during the analysis. High-performance liquid chromatography (HPLC) analysis was also performed for comparative purposes. High agreement between the NMR and HPLC methods was achieved in the determination of (R)-metoprolol in a standard solution of the (S) isomer.

• Journal of Astronomy and Space Sciences
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• 제37권4호
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• pp.249-255
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• 2020

We develop the tissue-equivalent proportional counter (TEPC) type's space radiation dosimeter to measure in-situ aviation radiation. That was originally developed as a payload of small satellite in the low-earth orbit. This dosimeter is based on a TEPC. It is made of an A-150 tissue-equivalent plastic shell of an internal diameter of 6 cm and a thickness of 0.3 cm. TEPC is filled with pure propane at 13.9 torrs to simulate a cell diameter of 2 ㎛. And the associated portable and low power electronics are also implemented. The verification experiments have been performed by the calibration experiments at ground level and compared with Liulin observation at aircraft altitude during the flight between Incheon airport (ICN) and John F. Kennedy airport (JFK). We found that the TEPC dosimeter can be used as a monitor for space radiation dosimeter at aviation altitude based on the verification with Liulin observation.

• 한국수산과학회지
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• 제56권1호
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• pp.124-132
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• 2023

This study aimed to cross between Korean and Japanese pure lines of Neopyropia strains to establish cross breeding technology and identify a superior variety that harbors the strength of both parents. Four crossing combinations were tried using three methods, resulting in 1,476 single conchocelis colonies. The three co-dominant Cleaved Amplified Polymorphic Sequence (CAPS) markers (EF-1α/Mse I, TOP2/Mse I, car A/ApaL I) were used to distinguish heterozygotic sporophytes and their maternal lines obtained from the inter and intraspecific cross-fertilization within the wild type of Neopyropia strains. Of the 1,476 colonies, 26.9% (218) were heterozygotes obtained from the nuclear CAPS markers. Their maternal line was clearly confirmed using organelle CAPS marker and chimeric thallus was obtained from crossing experiment of Japanese N. yezoensis (♀) and Korean N. yezoensis (♂). The use of CAPS markers improved the efficiency of crossbreeding by quickly screening heterozygotes and maternal lines in the conchocelis phase, which otherwise required pigmentation mutants as genetic markers.

• Journal of Forest and Environmental Science
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• 제26권1호
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• pp.17-23
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• 2010

The present study was conducted to quantify wood and leaf litter decomposition and nutrient release of a dominant tree species, Tectona grandis Linn. F. in a tropical dry deciduous forest of Rajasthan, Western India. The mean relative decomposition rate was maximum in the wet summer and minimum during dry summer. Rainfall and its associated variables exhibited greater control over litter decomposition than temperature. The concentrations of N and P increased in decomposing litter with increasing retrieval days. Mass loss was negatively correlated with N and P concentrations. The monthly weight loss was significantly correlated (P < 0.05) with soil moisture and rainfall in both wood and leaf litter. Tectona grandis was found to be most suitable tree species for plantation programmes in dry tropical regions as it has high litter deposition and decomposition rates and thus it has advantages in degraded soil restoration and sustainable land management.

• 한국환경과학회지
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• 제31권12호
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• pp.1061-1068
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• 2022

The purpose of this study was to develop a recycling system for ozone off-gas. Although the ozone transmission rate of the injector method differs slightly depending on the ozone injection rate, it reaches approximately 99%, which is very high. During the increase in water inflow to the ozone recycling system from 2 L/min to 10 L/min, the average ozone recycling rate was 99.4% at a 1 ppm ozone injection rate, 98.6% at a 2 ppm ozone injection rate, 98.1% at a 3 ppm ozone injection rate. Ozone treatment facility operating costs can be divided into the costs of pure oxygen production, ozone production, and maintenance. The annual operating costs of ozone treatment facilities in Korea are estimated to be approximately 38.9 billion won. The annual savings are estimated to be approximately 5.8 billion won when the ozone transfer rate of the diffuser method, which is mostly employed in domestic water treatment plants, is 85% and 15% of the ozone is recycled.

• 시큐리티연구
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• 제6호
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• pp.103-122
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• 2003

Protection sciences are new science. therefore, protection martial arts sciences are will studied be based on study of protection in order to supply high level by request. Moreover, It is reconstruction that protection martial arts masters education, systematic manage, certificate system, protection martial arts recognition certificate, protection martial arts equipment, practice of protection martial arts. Protection martial arts occurs on the unforeseen accident and body guarding, therefore martial arts concept of protection martial arts different general martial arts and sport. In order to develope of protection martial arts First, scientific thesis need of protection martial arts learning. Especially, aims of present protection martial arts is not protect oneself, protect the VIP to safely from all dangers is different thing with aims of general martial arts. Instinct that VIP protect rather than oneself should study and develop. Second, techniques and model of protection martial arts spread to who in connection with security service by systematic and organized. Preferentially, study of protection martial arts Techniques and model possible the protection martial arts learned society, found laboratory and endowed protection martial arts society organize and prevention for random of protection martial arts and must make the original protection martial arts. Third, protection martial arts official certificate and license system must organize in order to training and manage of protection martial art master, Match director(First Second), life physical director(First, Second, Third) is systematically manage by Ministry of Culture & Tourism Republic of Korea. Like this protection martial arts also classify the certificate by scholarship and experience. Fourth, In union to university, private security service company, public institution, police and system that possible leaning to protection martial arts certificate course important. In addition, destroy the commercial character of present martial arts and cultivate the pure martial arts mind, should develop to martial arts in order to improve the humanism and temperament of right body guard.

• 한국통신학회논문지
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• 제29권8A호
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• pp.950-961
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• 2004

이 논문에서는 최근 무선 통신 환경으로 증가하고 있는 지하철 터널 환경에서의 전파 특성을 측정하고 분석하였다. 측정은 지하철 터널에서 2.45㎓와 5.8㎓의 주파수 대역을 가지고 수행하였다. 측정을 위해 사용된 터널의 길이는 LOS(line of sight: LOS)가 175m이고, NLOS(non line of sight: NLOS)가 270m이다. 지하철 터널은 곡선형이며, 그 단면은 마제형(horseshoe type)이다. 측정 시스템은 협대역 시스템과 광대역 시스템을 이용한다. 협대역 시스템은 경로손실(path loss: PL) 측정을 위해 사용되고 광대역 시스템은 전력지연프로파일(power delay profile: PDP) 측정을 위해 사용된다. 특히, 광대역 시스템은 슬라이딩 코릴레이션 기법을 기반으로 80MHz 칩율과 1023길이의 PN 시퀀스 발생기로 구성하였다. 안테나 빔 형태에 따른 전파특성을 분석하기 위해서 무지향성 안테나와 지향성 안테나를 사용하였다. 경로손실은 터널 환경의 순수한 경로손실만을 나타내었다. 지연 프로파일은 평균초과지연(Mean Exess Delay)와 RMS 지연확산(RMS delay spread)에 대해서 분석하였다.