• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.67-74
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• 2006

This study was carried out to investigate the changes of essential oils in flue-cured leaf tobacco during aging for 21 months. The threshed leaf tobacco(BlO) produced in 2002 crop year was aged for 21 months in the warehouse of Oc-Cheon Leaf Tobacco Processing Factory. The leaf tobacco were sampled at three month intervals for analysis of volatile compounds. Volatile compounds were identified by GC/MS and comparison of gas chromatographic retention time with those of the authentic standard. The total of 75 compounds from the steam volatile concentrate of the flue-cured leaf tobacco were identified; they were 15 hydrocarbons, 12 alcohols, 3 aldehydes, 18 ketones, 7 esters, 10 acids, 3 phenols, 4 furans, 2 pyrrols and 1 pyridine. The major components of essential oil were neophytadiene, solanone, megastigmatrienone and phytol. After a aging period of 21 months, most of volatile compounds showed a gradual increasing tendency.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.1
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• pp.107-117
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• 2016

This study investigates design strategies for improving the educational quality of multimedia contents for early childhood education. It emphasizes both traditional education theory and developmental aspects in its exploration of interactive and educational qualitative multimedia contents for early children. Accordingly, for an effective early childhood education, it is necessary to experience of the playful learning for the conception of ideas and the understanding of the social life. Because this study 1) possibility of multimedia contents for early childhood education, 2) computer application method for early childhood education, 3) examines used in the designing of multimedia contents for early childhood education according to traditional education theory. Multimedia early childhood education system is possible to organize information such as test, image, sound and video based on hyperlink system. I use Microsoft's Ms-office and Asymetrix's ToolBook software that are useful for hyperlink and parameter. Multimedia contents and other pages are used by Dynamic Data Exchange(DDE). Therefore multimedia contents for early childhood education is a useful tool for students of early childhood education department, parents, and children.

• New & Renewable Energy
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• v.19 no.3
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• pp.22-33
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• 2023

The number of fire and explosion accidents caused by pyrolysis oil and gas at waste plastic pyrolysis plants is increasing, but accident status and safety conditions have not been clearly identified. Therefore, the aim of the study was to identify the risks of the waste plastic pyrolysis process and suggest appropriate safety management measures. We collected information on 19 cases of fire and explosion accidents that occurred between 2010 and 2021 at 26 waste plastic pyrolysis plants using the Korea Occupational Safety and Health Agency (KOSHA) database and media reports. The mechanical, managerial, personnel-related, and environmental problems within a plant and problems related to government agencies and the design, manufacturing, and installation companies involved with pyrolysis equipment were analyzed using the 4Ms of Machines, Management, Man, and Media, as well as the System-Theoretic Accident Model and Processes (STAMP) methodology for seven accident cases with accident investigation reports. Study findings indicate the need for establishing legal and institutional support measures for waste plastic pyrolysis plants in order to prevent fire and explosion accidents in the pyrolysis process. In addition, ensuring safety from the design and manufacturing stages of facilities is essential, as are measures that ensure systematic operations after the installation of safety devices.

• Journal of The Korean Association of Information Education
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• v.9 no.4
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• pp.571-579
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• 2005

교수-학습과정에서 학습자가 가지고 있는 학습 장애는 학습 결과에 많은 영향을 미친다. 학습자의 학습 장애를 정확하게 진단하고 이를 고려한 수업 활동이 전개되어야 효과적인 교수-학습 활동이 이루어 질 수 있다. 학습 장애의 특성상 장애 진단과 처방과정에서는 비공개적인 접근이 요구된다. 인터넷 기반의 온라인 학습 장애 진단과 처방시스템은 이와 같은 문제를 해결할 수 있는 유용한 방안 중의 하나가 될 것이다. 하지만 기 구축되어 운영 중인 온라인 기반 학습 장애 관련 사이트들은 학습 장애를 진단해 주고 처방해 주기 보다는 학습 장애 정보를 안내해 주는 정도의 수준에 에 그치고 있다. 단순히 웹문서 형태의 정보제공 체제이거나 텍스트 기반의 지식 전달 체계로 인하여 학습자 개개인의 특성을 고려한 장애 진단에 한계점을 가지고 있다. 학습 장애에 대한 지식을 체계화함과 동시에 일정한 기준에 의해 연관성을 지어 줄 수 있는 의미 분석과 추론 등의 방법에 사용되어지는 온톨로지를 활용하게 되면 기존의 시스템이 가지는 제한점들을 극복할 수 있을 것이다. 이에 본 연구에서는 온라인 상황에서 학습자의 학습 장애를 정확하게 진단하기 위해 온톨로지를 이용하여 학습장애 진단 시스템을 설계하고 구현하였다. 온톨로지의 구축에 사용된 도구는 protege-2000을 사용하였다. 진단시스템 개발 환경으로 학습자의 인터페이스는 Visual C++, 교사의 인터페이스는 Visual Studio.NET을 사용하였으며, DBMS는 Microsoft Office Access와 MS-SQL Server를 사용하였다. 이 연구는 OWL 온톨로지를 사용하여 보다 지능화된 학습 장애 진단시스템을 개발함으로써 실현 가능성을 제안하고 있는 것이 연구의 의의이다.

• Journal of Engineering Education Research
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• v.27 no.3
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• pp.14-25
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• 2024

The purpose of this study was to conduct a needs analysis among experts regarding the curriculum in the field of new and renewable energy for the future experts. To achieve this goal, purposive sampling was employed to select 30 experts from the reginal, industrial, academic, and research sectors in the new and renewable energy field, who participated in needs surveys and expert Delphi surveys. Needs assessments for 53 courses and suitability evaluations for 6 curriculums were conducted, and comprehensive advisory opinions were gathered. Data were analyzed using t-tests, Brich's needs assessment, the locus for focus model, and content analysis methods, with the assistance of MS Office Excel 2018 and SPSS 25.0 software. The key findings include: (a) 18 courses should be given top priority for operation, while 4 courses should be considered secondarily; (b) All 6 curriculums received positive evaluations; (c) Improvements are needed in curriculum development to cater to both generalist and specialist training needs, incorporating the acquisition of new technology and project-based learning experiences. The results of this study provide implications for the development of customized curriculums in the new and renewable energy industry.

• Journal of Plant Biotechnology
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• v.39 no.2
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• pp.114-120
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• 2012

An efficient in vitro propagation was established by using axillary bud explants of roseroot (Rhodiola rosea L.), which has been known as a medicinal plant in East Asia. Among various media tested, MS medium supplemented with 1.0 mg/L BA and 1.0 mg/L $GA_3$ was found to be the best for multiple shoot formation (15 axillary shoots per axillary bud). In addition 1/2MS medium containing 50 g/L sucrose was best for shoot elongation (7.8 cm) and increasing total chlorophyll contents (8.64 mg/g) best. Maximum number of roots (17.7 roots per explant) was observed on the medium without plant growth regulators. Propagated plants were successfully acclimatized to ex vitro conditions, with a survival frequency of 97% after 12 weeks. Most rooted shoots grew well and produced viable seeds when grown in vitro culture conditions. Therefore, R. rosea can be effectively propagated in vitro by the system we developed in this study.

• The Journal of the Korea Contents Association
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• v.4 no.4
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• pp.123-131
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• 2004

Internet is absolutely contributed to information technology revolution nowadays. Internet services such as voice and data, etc. are provided home or small office via home gateway. The development of communication equipment via home gateway is implemented rapidly, and its product various. This paper presents the design and implementation of the VoIP equipment including the telephone function based on the embedded environment and being connected to the home gateway and the PC because of taking 2-ethernet LAN ports. As developing environment, the STLC1502 developed at ST Microelectronics as single chip solution, VxWorks as RTOS, and C language as coding mechanism are used. The verification of the developed systems for the voice test is carried out for the gatekeeper via Internet. The performance parameter is considered as the call processing capacity measuring the time of the call setup and clearing, and the data processing capacity for the file transfer. As a call setup and clearing is about 95ms, the call processing capacity is about 10 calls per second. The data processing capacity is 5.7Mbps in case of file transfer of server and client environment. Therefore the performance result is satisfied in the aspect of the call processing time and the data transfer time in Internet.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.294-302
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• 2015

BACKGROUND: Chemical accidents have increased owing to chemical usage, human error and technical failures during the last decades. Many countries have organized supervisory authorities in charge of enforcing related rules and regulations to prevent chemical accidents. A very important part in chemical accidents has been coping with comprehensive first aid tool. Therefore, the present research has provided information with the initial applications concern to the rapid analysis of hazardous material using instruments in vehicle of field mode after chemical accidents. METHODS AND RESULTS: Mobile measurement vehicle was manufactured to obtain information regarding field assessments of chemical accidents. This vehicle was equipped with four instruments including gas chromatography with mass spectrometry (GC/MS), Fourier Transform Infrared Spectroscopy (FT-IR), Ion Chromatography (IC), and UV/Vis spectrometer (UV) to analyses of accident preparedness substances, volatile compounds, and organic gases. Moreover, this work was the first examined the evaluation of applicability for analysis instruments using 20 chemicals in various accident preparedness substances (GC/MS; 6 chemicals, FT-IR; 2 chemicals, IC; 11 chemicals, and UV; 1 chemical) and their calibration curves were obtained with high linearity ( r ² > 0.991). Our results were observed the advantage of the high chromatographic peak capacity, fast analysis, and good sensitivity as well as resolution. CONCLUSION: When chemical accidents are occurred, the posted measurement vehicle may be utilized as tool an effective for qualitative and quantitative information in the scene of an accident owing to the rapid analysis of hazardous material.

• 보존과학연구
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• s.22
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• pp.5-25
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• 2001

The germicidal and insecticidal properties of volatile components extracted from star anise(Illicium verum Hooker filius) and clove (Eugenia caryophyllata THUNBERG)were evaluated against five microorganisms and three insects for the purpose of developing biocidal active substances from medicinal plants. The volatile components of star anise and clove showed strong antimicrobial effect against Aspergillus niger, Penicillium funiculosum, Mucor hiemalis, Trichoderma viride, and Aureobasidium pullulans. The extracts of each medicine also showed insecticidal effects against Sitophilusoryzae L., Lyctus linearis GOZE, and Reticulitermes spertus kyushuensis Morimoto. Fumigant toxicities to adult insects were determined. In the case of fumiganttoxicity, the extract of star anise showed 100% mortality against R. spertus, S.oryzae, and L. linearis at rates of $2.5\mu\ell$, $50\mu\ell$, $250\mu\ell$/filter paper, respectively but showed no killing effects by clove. The volatile components of star anise and clove were investigated by means of GC/MS. The main constitute, anethole among 20components from star anise and eugenol among 9 components from clove were identified. The mixture of star anise and clove as the volume ratio of 2 : 1 showed higher properties for antimicrobial and insecticidal effect than each volatile component. A. niger was inhibited by the mixture(125ml/$m^3$) for up to 10 days of exposure. Also, from the result of observing state change of organic materials by volatile extracts of star anise and clove, volatile extracts effects have no effect on natural organic materials of organic cultural properties and can be used as biological control agent. As research contents as above, the insecticidal and germicidal agents from star anise and clove and the mixture of them were more efficient and high level to prevent biological damage for conservation of organic cultural properties. So they may be used in new development of biologicalinsecticidal and germicidal agents for conservation of cultural properties.

• Atmosphere
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• v.19 no.1
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• pp.37-51
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• 2009

Kinematic characteristics of a heavy rainfall event occurred in Changma front are analyzed using synoptic weather charts, satellite imagery and NCEP(National Centers for Environmental Prediction) / NCAR(National Centers for Atmospheric Research) reanalysis data. The heavy rainfall is accompanied with mesoscale rain clouds developing over the Southwest region of Korea during the period from 0300 LST to 2100 LST 25 June 2006. The surface cyclone in the Changma front is generated and developed rapidly when it meets following vertical conditions: The maximum value of relative vorticity is appeared at 700 hPa and is extended gradually near the surface. It is thought that the vertical structure of relative vorticity is closely related with the descent of strong wind zone exceeding $10ms^{-1}$. The jet core at 200 hPa is shifted southward and extended downward and the low-level jet stream associated with upper-level jet stream appeared at 850 hPa. Kinematic features of heavy rainfall system at cyclone-generating point are as follows: In the generating stage of cyclone, the relative vorticity below 850 hPa increased and the convergence below 850 hPa and the divergence at 400 hPa are intensified by southward movement of jet core at 200 hPa. The heavy rainfall system seems to locate to the south of the exit region of upper-level jet streak; In the developing stage of cyclone, the relative vorticity below 850 hPa and the convergence near surface are further strengthened and upward vertical velocity between 850 hPa and 200 hPa is increased.