• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.1
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• pp.74-81
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• 2002

Combustion phenomena in a sub-millimeter scale combustor have been investigated. To evaluate scale effect on flame propagation characteristics, a cylindrical combustion chamber with variable depth was built in-house. The combustor was charged with premixed gas of hydrogen and air and ignited electronically. A piezo electric pressure transducer recorded transient pressure after the ignition. Measurements were made at different test conditions specified with chamber depth and initial pressure as parameters. Visual observation was made through a quartz glass window on top side of the combustion chamber using high speed digital video camera. From the pressure data, available work was estimated and compared with energy input required for stable ignition. The preliminary results suggested that the net thermal energy release is sufficient to generate power and enables a combustor of the size in the present study to be used as the energy source of a micro power devices .

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.180-184
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• 2005

These days, home network connects all home appliances using one of broadband convergence network, is constructed and propagated to more than 10 million house hold. Users can monitor and control statuses of home appliances using mobile terminal through homeserver. For active propagation of home network, high-quality multimedia service is very important. Specially, as digital recorder and digital camera is propagated, new paradigm that private DVDs can be shared in many household shows up. The homeserver is the main part of UbiHome, which can store much multimedia content and through which the user can search and share these contents. For searching and sharing, the metadata of contents is supposed to keep the consistency. These metadata include the description to different format such as Image, movie, and music. Therefore, we intend to provide a RDF model for effectively storing, searching and managing high-quality contents in UbiHome. In this paper, we propose to make Ontology to close semantic approach using RDF/RDF Schema for managing multimedia data in UbiHome. we propose RDF-Based Local Ontology and merging these ontology to RDF-Based Global Ontology.

• Journal of Korean Society of Forest Science
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• v.40 no.1
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• pp.43-50
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• 1978

The elder berry was known to the rich in natural food colour resources and used in as for making wine, confectionary, perfumes, natural food colour, making elder berry juice, jelly, jam and medicinal properties or oils. In the present study, wish was to find the effect of various factors on the success of the vegetative propagation of elder berry by means cutting in the exposed field and green house was carried out and those obtained results can be summarized as follows. 1. Cuttings with dormant cutting stocs in the polyethylen house with heating and water mist spray resulting 100 percent survival. And temperature and the relative humidity in which fraim during the cutting season were around $20{\sim}25^{\circ}C$ and 70-90% respectively and in case as more significant other of the 1% Level. 2. With five varieties tested, resulting 93.8 percent survival, The F. value is not significant. 3. With four organs of cutting stock tested resulting 57.5 percent survival on the cuttings with two knodes of dormant cutting stock served as better cutting stock than others. The F. value is more significantly 1% Level. 4. Dormand bud served as possible cutting stock was found to be 17.66 survival percentage. 5. Both earlier and later stage of germinated Leaves with soft wood cutting stock poor cuttings, and the degree of development of 15th June cutting stock was optimum stage on the principal factor governing the success of cutting in the soft wood cutting showing 54% survival. The F. value is more 1% Level significant.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.273-277
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• 2011

Fusarium oxysporum f. sp. fragariae (Fof), the causal agent of crown and root rot in strawberry, is the most serious soilborne disease of nursery plants in Korea. The possibility of infection by Fof through runner propagation from infected mother plants of strawberry cv. 'Kumhyang' was assessed in stolons and daughter plants hanging from raised beds. The number of daughter plants from an infected mother plant in plastic house and photosynthetic photon flux (PPF) system, 280 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was 2.7 and 3.8 plants after 58 days, respectively. However, healthy mother plants produced 6.5 and 8.4 daughter plants, respectively. The pathogen was detected in the uppermost portion of the stolon after 58 days, but was not detected further down the stolon. After 90 days, it was detected in all portions of the stolon between mother and $1^{st}$ daughter plant and in 60% of all $1^{st}$ daughter plants. The pathogen was not detected in the corresponding portions of the non-infected controls. These results show that infected mother plants can transmit Fof to their daughter plants without passing through the soil and $1^{st}$ daughter was used as mother plant in PPF system for propagating healthy plants.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.2
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• pp.174-180
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• 2017

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the lean combustion limit and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.273-276
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• 1995

In vitro propagation of Neoregeria carorinae 'Tricolor' was achieved by using immature flowers and lateral buds, and the plantlets from tissue culture were transplanted and cultivated in greenhouse. The picking times of explants to decrease disappearance of stripes, and in vivo the growth and flowering of regenerated plantlets as influenced by in vivo healed nun were investigated. The normal plantlet were obtained at a frequency of 67%, in the culture of immature flowers picked at 4 weeks after flower bud differentiation, while all leaf stripes disappeared in the culture of immature flowers picked 1 and 5 weeks after flower bud differentiation. In vivo growth of plantlet from immature flower buds was better than those from lateral buds, and the flowering of 27.8% showed in the greenhouse culture of plantlet from immature culture, but the plantlets from lateral buds did not flower at all. The plantlets rooted on the medium with 0.5 mg/L IBA were the most favorable in green house culture, and the kinds and concentrations of auxin in vitro did not have any influence on variation of plane cultured in greenhouse.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.11
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• pp.1121-1128
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• 2016

Our country of agriculture suffers problems such as aging, population decline, agricultural decline etc. To solve this problem, in the country, it is interest in Smart Farm System, a convenient and efficient system for the production through the convergence of ICT technology and agriculture. However, because of expensive construction costs and difficulty in securing human resources and training for Operating system, they are struggling to spread the actual farmers. Therefore, it is necessary to develop smart farm techniques suitable for such customized domestic environment. This study designed a system for collecting environment date in a greenhouse based on the low-cost embedded devices, and designed and implemented for the Web application that a user can easily use system. The implementation of the system lowers deployment costs and is expected to increase largely the spread of Smart Farm it can be easily accessed by using the smart phone.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.4
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• pp.357-364
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• 2016

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the combustion stability and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.85-94
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• 2013

This paper presents a novel mobile measurement system with multi antennas which enable mobile measurement as well as fixed measurement with telescope mast. Proposed system installed 4 omni directional antennas for the space diversity process and one directional log periodic antenna for the simultaneous conventional fixed measurement. Whole antenna systems are connected to the custom DTV channel analyzers with Ethernet networks respectively and processed by the main controller to calculate real time average receive levels. To prove the performance of proposed system, the typical receive models are categorized as 3 area types - open area, building area and house area, and then intensive field tests were performed through mobile and fixed measurement phases. With these measurement data, the relationships between mobile and fixed measurement are analyzed, and the concept of compensation factor is proposed to assume the average receive level of signal. The field test is fulfilled as a co-work with public broadcasters and the proposed system is applied to the intensive coverage measurement projects for metropolitan areas by the korean government agencies.

• Journal of Animal Environmental Science
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• v.2 no.1
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• pp.1-11
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• 1996

This study was conducted to analyze the present status and the levels of mechanization and automation for raising, feeding, water supply, propagation, health management, ventilation and heat control, data analysis, and etc, and to establish the guide of the future study on development of the optimum production system models of swine facility from the results of this analysis. The scheme of the future study on the development of the optimum production system model of swine facility was established as follows : 1. A Korean and environmental control type slatted windowless swine housing model would be developed according to the following basis : \circled1 Boars, gilts and sows, delivery sows should be raised individually and piglets, growing pigs, and finishing pigs should be raised in group. \circled2 The arrangement of furrowing house were two rows of furrowing crates facing the center aisle. 2. The environmental control system and waste management system that are suitable to Korean and environmental control type slatted windowless swine housing model would be developed. 3. An electronic identification device would be developed. 4. The automatic individual wet feeding system by electronic identification device and computers would be developed. 5. The individual management system would be developed, which could manage individually the breeding pigs by the electronic identification device. 6. An expert system would be developed, which could manage the health and data base of pigs.