• YAKHAK HOEJI
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• v.26 no.2
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• pp.91-96
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• 1982

In an attempt to design prodrugs for the Derivatives of the Isothiocyanates R-N=C=S were synthesized eleven novel bis-dithiocarbamates. The best way of preparing the dithiocarbamates was the formation of the dithiocarbonates followed by the reaction of the dithiocarbonates with amines. Thus, the treatment of the diols with carbon disulfide in the presense of potassium hydroxide afforded the potassium salts of the ditniocarbonic acids. The potassium salts were then reacted with alkyl halides to give the dithiocarbonates, which upon treatment with amines produces the dithiocarbamates. In case of vicinal diol (n=o in the above formula), only one of the hydroxy groups was reacted to give the mono-dithiocarbonate. The dithiocarbonates failed to react with amides and aromatic amines. Dithiocarbonates of the different types were obtained when the active double bonds, such as $CH_{2}=CH-Z$ , (Z are electron withdrawing groups), were allowed to react with the free dithiocarbonic acids produced in situ by carefully neutralizing the Potassium salts of the corresponding acids. These compounds are considered to be of some value as prodrugs for the active double bonds.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.30
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• pp.25-34
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• 1994

Mental workload has a improtant place in modern work environment such as human-computer interaction. Designing man-machine system requires knowledge and evaluation of the human cognitive process which controls information flow during our works. Many studies estimate reaction time as a index of menatal workload. This paper investigates what reflacts the workload of human information handling when the informations grow its degree. Experiment result introuce the memory time that explain the information-load more sensitive than react time. And react time shows learning effect but memory time does'nt show that effect So it can be concluded that cognitive learning or work schema needs more time to achieve dexterity than motor skill.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.469-470
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• 2023

내연기관 자동차는 연료 소모로 인해 대기 중에 유해 물질과 온실가스를 배출한다. 반면에 전기 자동차는 전기로 작동되어 대기 중 오염을 줄이고 친환경적인 운행을 제공한다. 전기차 대여 시스템을 도입함으로써, 사용자들에게 친환경적인 교통수단을 이용할 수 있는 기회를 제공하고, 탄소 배출량을 줄이는 데 크게 기여할 수 있기에 해당 연구를 진행하였다. 이 연구에는 React 기반의 Next.js 웹 프레임워크를 이용하여 클라이언트 측과 서버 측 렌더링을 지원하고 사용자들에게 빠른 반응 속도와 사용 편의성을 제공한다. Bootstrap을 이용하여 사용자 인터페이스(UI)를 개발하고, 전기 자동차 대여 서비스에 필요한 화면을 구성하였다. 또한 Node.js 기반의 Express.js 웹 프레임워크를 이용하여 서버 사이드 로직과 RESTful API를 개발하는 데 사용하고 데이터베이스와의 통신, 사용자 인증, 대여 정보 관리 등을 처리하였다. 이러한 기술적 개발을 통해 전기 자동차 대여 시스템은 실용적이고 효율적인 서비스를 제공하며, 환경 보호와 탄소 배출 감소에 기여할 수 있는 프로젝트라고 볼 수 있다.

• Journal of the Korean Chemical Society
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• v.16 no.1
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• pp.40-45
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• 1972

An electron spin resonance study has been made on lysozyme in. frozen aqueous solutions irradiated with $_{60}Co$ r-rays in air at $77^{circ}K.$ Water resonances are dominant when the concentration and the temperature are both below 20% and $130^{circ}K$ respectively. More solute radicals are produced in the solution of higher concentration. Majority of the solute radicals results from direct hit of the radiation. The same types of radicals are induced at $77^{circ}K$ whether the substances are irradiated in the dry state or in frozen aqueous solution. Based on these results, it is assumed that the number of ESR centers produced by the secondary intermolecular radical reacions and stabilized in aqueous solutions may depend on the concentration of the solution, and the presence of water may facilitate the secondary radical reactions occuring in the solute molecules after heat treatment. Majority of the solute radicals above around $193^{circ}K$ are believed to react with oxygen to form peroxytype radicals. However, when the solution is subiected to heat-treatment at $265^{circ}K$ after irradiation at $195^{circ}K$ the peroxy-type resonance was not observed, suggestin that an appreciable amount of oxygen is condensed into the ice, at $77^{circ}K.$ in addition to the oxygen that has already been dissolved in solution and react with solute free radicals during the process of heat-treatment. When the solution contains $H_2O_2$, no water resonance but $HO_2$, type resonance was observed probably indicating that the radiation-induced OH radicals are trapped in $H_2O_2$ aggregates and react readily with $H_2O_2$ molecules to poroduce $HO_2$ type radicals even at $77^{circ}K.$.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.15-21
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• 2000

In chlorine dioxide delignification and bleaching the formation of chlorate is undesirable because it does not react with lignin and is harmful to the environment. Chlorate is mainly formed from the in-situ generated hypochlorus acid which is also the main reason for AOX formation. In previous literature scavengers of hypochlorous acid such as sulfamic aicd, DMSO, and hydrogen peroxide have been added to bleaching stages to reduce AOX formation but less attention has been paid to chlorate reduction. This paper thus focuses on the reduction of chlorate content caused by the following additives, sulfamic acid, DMSO, hydrogen peroxide, and oxalic acid. The results show that only sulfamic acid and DMSO reduce chlorate formation under our chlorine dioxide prebleaching conditions. Results by UV spectroscopy and pH adjustment show that scavengers react with hypochlorous acid much faster than with chlorine. Hydrogen peroxide and oxalic acid react with HClO/$Cl_2$much slower than DMSO and sulfamic acid do. The reason for the ineffectiveness of hydrogen peroxide and oxalic acid is ascribed to their slow reaction rates with HClO compared to that of chlorate formation. The fact that only 30-35% of the chlorate can be reduced by sulfamic acid and DMSO when charged in same mole ratio to chlorine dioxide, suggested that the reaction rate of DMSO and sulfamic acid with hypochlorous aicd are of the same magnitude as that of chlorate formation.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.118-125
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• 1998

This study investigates the react characteristics to suggest the condition of the utilization and disintegration of food garbage as composting by varying the supply amount of air of the fermentation reactors. With the initial temperature and agitation velocity maintained 50$\circ$C and 1 rpm, the supply amount of air gives variety to 0.5, 1, 2, 4 l/kg$\cdot$ min. In the case of the amount of air operated at the 0.5 l/kg$\cdot$ min, reaction temperature shows a rising to the maximum 66$\circ$C after the 48hr, and the oxygen used rate of the micro-organisms shows the largest level at 18.4% after the 8hr. In the case of $NH_3, H_2, H_2S$ and SO$_2$ among the react gas, the sanitary utilization shows the possibility of the microorganisms gas disintegration, with most high gas generate rate. In the case of the amount of air operated at the 1, 2 and 4 l/kg$\cdot$ min, initial react was advanced rapidly and the product of the 72 hr after shows big weight reduction. As the experimentation result, when the amount of air operated at the 1 l/kg$\cdot$ min over, the reduction by disintegration would be more effectively, for the reactor maintains the color tone and shape of the straw (bulking agent).

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.196-196
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• 2011

Molecular $N_2O$ has bee known to react over oxygen vacancy on a reduced rutile $TiO_2$(110)-1${\times}$1 surface to desorb as molecular $N_2$ leaving oxygen atom behind. In the present study, we investigated the reaction of $N_2O$ on rutile $TiO_2$(110) using temperature-programmed desorption (TPD). Our results indicate that $N_2O$ does not react over the oxygen vacancy under a typical UHV experimental condition. On a rutile $TiO_2$(110)-1${\times}$1 with a well-defined oxygen vacancy concentration of 5% ($2.6{\times}10^{13}/cm^2$), $N_2O$ desorption features show a monolayer peak maximum at 135 K followed by a small peak maximum at 170 K. When the oxygen vacancy is blocked with $H_2O$, the $N_2O$ peak at 170 K disappears completely, indicating that the peak is due to molecular $N_2O$ interacting with oxygen vacancy. The integrated amount of desorbed $N_2O$ plotted against the amount of adsorbed $N_2O$ however shows a straight line with no offset indicating no loss of $N_2O$ during our cycles of TPD measurements. In addition, our $N_2O$ uptake measurements at 70~100 K showed no $N_2$ (as a reaction product) desorption except contaminant $N_2$. Also, $H_2O$ TPD taken after $N_2O$ scattering up to 350 K indicates no change in the vacancy-related $H_2O$ desorption peak at 500 K showing no change in the oxygen vacancy concentration after the interaction with $N_2O$.

• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.55-58
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• 2009

Density functional theory was used to investigate the adsorption and reaction of $HfCl_4$ with two hydroxyls on Si (001)-$2{\times}1$ surface in atomic layer deposition (ALD) process. We prepared a reasonable Si substrate which consisted of six inter-dimer dissociated $H_2O$ molecules and two intra-dimer dissociated $H_2O$ molecules. The $HfCl_4$must react with two hydroxyls to be a bulk-like structure. When $HfCl_4$ was adsorbed on a hydroxyl, there was energy benefit of -0.55 eV. Though there was energy loss for $HfCl_4$ to react with H of hydroxyl, thermal energy of ALD chamber would be enough to pass the energy barriers. There were five reaction pathways for $HfCl_4$ to react with two hydroxyls; inter-dimer, intra-dimer, cross-dimer, inter-row, and cross-row. Inter-row, inter-dimer and intra-dimer were relatively favorable among the five reaction pathways based on the energy difference. The electron densities between O and Hf in these three reactions were higher than the others and they had shorter Hf-O and O-O bond lengths than the other two reaction pathways.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.1
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• pp.134-139
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• 2022

Recently, interest in programming and artificial intelligence is continuously increasing, and software education is being implemented as a mandatory education from elementary school. For efficient programming education, it is basically necessary to build a lab environment suitable for students and teachers, but there are performance problems due to the inadequacy of old computers and network equipment. Therefore, in this paper, we propose a web page-based online practice environment and algorithm competition scoring system using React and Spring boot to solve the problem of the programming practice environment. Through this, it is thought that programming learning can be carried out using only a web browser even on low-spec computers. In addition, since various programming languages can be learned irrespective of the language to be learned, it is considered that the time cost for establishing a practice environment can be reduced.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.450-452
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• 2021

Recently, as interest in programming and artificial intelligence has increased, software education has been compulsory from elementary school. In order to achieve this goal of programming education, it is necessary to basically establish a lab environment suitable for students and teachers. However, there is a problem with performance problems caused by old computers in the lab environment of the school, and there is a problem that students must purchase and use the existing online platform while implementing an algorithm contest program in which students access and evaluate their problem-solving ability at the same time. Therefore, in this paper, to solve this problem, we propose a web-based online practice environment and algorithm contest scoring system using React and Spring boot. Through this, it is believed that even in a computer with low specifications, programming can be studied using only a web browser.