• Electronic Materials Letters
• /
• 제14권6호
• /
• pp.712-717
• /
• 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 $CH_3NH_3PbI_3$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 한국해양정보통신학회 2009년도 추계학술대회
• /
• pp.924-927
• /
• 2009

IP reuse technology, for the sake of out-performance and the reduction of development period of IT-SoC is the most essential factor for the sound growth of SoC industry. As for this IP reuse technology, it is very important to decide the proper specification and the standardization of the requirement from the companies, as well as to develop our own domestic technological know-how which does not depend on import. In this study, we propose to analyze a security core IP with pure domestic technological know-how, mentioning an example from $CAST_{TM}$, which presently is an American company costing royalty.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 한국정보통신학회 2016년도 추계학술대회
• /
• pp.415-418
• /
• 2016

The core of IT Convergence Education is being made through educational SW, SW purpose of education has been focused on improving the CT(Computational Thinking). In this paper, Programming Education Using Unity3D is able to affect learners of computational thinking and learning interest. After configure the experimental and control groups and check the identity of the learner for Influence on it. The impact on the education using Unity3D computational thinking and learning interest of students was measured. This paper proposes a compliance that Programming Education Using Unity3D is an intermediate step of utilizing the EPL software training, and pure text language.

• Analytical Science and Technology
• /
• 제34권1호
• /
• pp.9-16
• /
• 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
• /
• 제37권4호
• /
• pp.249-255
• /
• 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.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• 제56권1호
• /
• pp.124-132
• /
• 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
• /
• 제26권1호
• /
• pp.17-23
• /
• 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.

• Journal of Environmental Science International
• /
• 제31권12호
• /
• pp.1061-1068
• /
• 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.

• Korean Security Journal
• /
• 제6호
• /
• pp.103-122
• /
• 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.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• 제29권8A호
• /
• pp.950-961
• /
• 2004

In this paper, we measured and analyzed propagation characteristics in a subway tunnel that is recently increasingly becoming one of the radio communication environments. The measurements are carried out in a subway tunnel with frequency bands of 2.45㎓ and 5.8㎓. The length of tunnel we used for this study is 175m of LOS (Line-of-sight) and 270m of NLOS (Non Line-of-Sight). The subway tunnel is curved and its cross section is horseshoe type. The measurement systems we employ in this study are a narrow-band system and a wide-band system. The narrow-band system is used to get path loss measurement and the wide-band system is used to figure out delay profile measurement. In particular, the wide-band system consists of 1023 length PN sequence generator using a chip rate of 80MHz based on a sliding correlation technique. The omni-directional antennas and directional antennas are used to analyze propagation characteristics for beam type of antenna. The path loss displays only pure path loss of a tunnel environment. The delay profile indicates the mean excess delay and RMS (root mean square) delay spread.