• Transactions of Materials Processing
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• v.21 no.2
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• pp.131-137
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• 2012

With the advantages of power savings, increased life expectancy and fast response time over traditional incandescent bulb, LEDs are increasingly used for many applications including automotive, aviation, display, and special lighting applications. Since the high heat generation of LED chips can reduce service life, degrade luminous efficiency, and cause variation of color temperature, many studies have been carried out on the optimization of LED packaging and heat sinks. In this study, a fin expansion type cooling device using heat pipe, instead of a solid aluminum heat sink, was designed for LED security lightings based on thermal resistance analysis. Numerical analysis and experimental validation were carried out to evaluate its cooling performance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.878-883
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• 1994

최근들어 국내 제조업 분야의 대외 경쟁력을 향상시키기 위해 각 산업체에서는 여러가지 자동화 시스템을 구축하려는 경행이 지배적이다. 자동화 시스템을 구축하는 방법 및 개상은 여러가지가 있을수 있으며 그 중에서 설계를 담당하는 자동화 시스템의 개발은 제품 생산을 위한 독자적인 기술을 확보하기 위해서 반드시 필요한 대상중의 하나이다. 그러나 대개의 경우 설계 과정은 상당히 복잡하고 어려운 작업으로서 최종 제작 도면을 만들어 내기까지에는 몇 가지 단계를 거치게 된다. 이들 과정을 설계를 수행하는 기술자가 보다 쉽고 빠르게 처리할수 있는 자동화 시스템을 구축한다면 제품생산에 상당한 파급효과를 기대할 수 있을 것이다. 본 연구에서는 설계 공리를 이용하여 제품 설계의 전 과정을 분석하고 제품 설계자가 쉽게 설계를 수행할 수 있도록 자동화용 소프트웨어 시스템을 구축하는데 목표를 둔다. 개발된 소프트웨어 대상은 TV브라운관 유리제품(glass bulb) 으로서 현재 수행되고 있는 제품 설계의 전과정을 설계공리의 관점으로 재 조명하고 효율적으로 개선하는 몇 가지 소프트웨어를 구축하였다. 전체 시스템은 메뉴 시스템을 적용한 사용자 인터페이스 기법을 이용하여 사용자가 보다 편리하게 설계과정을 수행할 수 있도록 하였다.

• Journal of Biosystems Engineering
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• v.27 no.6
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• pp.513-520
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• 2002

A 5-row walking garlic harvester with pulling mechanism was developed in the study, based upon a kinematical analysis and related preliminary field tests on the conventional garlic harvesting method. The harvesting efficiency of the developed harvester was more than 98% in the garlic field irrigated before harvesting, 80-85% in the field without irrigation. The harvesting performance of the harvester was 660∼825㎡/hr at the forward speed of harvester of 0.3m/s in the irrigated field before garlic harvesting. For proper garlic drying and collection, the harvester discharged the harvested garlic on the ground uniformly at the angles of 135。∼150。 to its forward direction with the garlic bulb's placing toward the harvester. In the field tests, it was recommended that the forward speed of the harvester be approximately less than 0.2m/s, and that the spacing of planting garlic seeds should be standardized in the future fur increasing its harvesting efficiency.

• Journal of Industrial Technology
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• v.32 no.A
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• pp.35-38
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• 2012

We present a novel non-dispersive infrared (NDIR) $CO_2$ gas sensor with a light source emitting collimated light. Using this thermopile, we also have successfully developed a small, sensitive NDIR $CO_2$ detector module for accurate air quality monitoring systems in energy-saving building and automotive applications. The novel sample cavity comprising specular reflectors around the light bulb is configured to uniformly emit collimated light into the entrance aperture of the cavity in order to enhance the sensitivity of NDIR $CO_2$ detector.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.188-193
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• 2009

유리벌브는 다양한 자동 소화장치 또는 시설에 신뢰성이 높은 감열체로서 각광받고 있다. 당사는 최근 작동온도가 매우 균일하고 하중강도가 우수한 유리벌브를 개발하였고 양산화에도 성공하였다. 본 논문에서는 당사가 개발한 유리벌브의 품질특성을 소개하고자 한다. 특히 본 연구에서는 화재 감지용 감열체로서 유리벌브의 주요 특성치인 반응시간지수 (RTI)에 대해 비중 있는 연구를 진행하여 유리벌브의 RTI를 결정하는 주요 변수들을 도출하고, 이를 설계에 응용하여 유리벌브의 RTI를 조절할 수 있는 툴로서 개발하였다.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.2
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• pp.1-7
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• 1998

Hull form development of the medium size high speed fishery patrol ship was carried out in the CWC at Chosun university. Same size of 15 knots class fishery patrol ship was selected as a parent form(Model number : CU-015), and modified fore and after body hull form under the slightly lengthened lo be suitable for the operation at 20 knots. To minimize the breaking wave in the vicinity of fore body at high speed zone, high bulb and sharp entrance angle were adapted. Meanwhile, to enlarge the engine room space keeping high resistance and sea-keeping Performance, U-type stern hull form was developed. Although the hull form was highly constrained in being limited to modification of a parent hull form significant wave resistance improvement was made.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.104.1-104
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• 2003

To screen for potential biocontrol agents against postharvest disease of garlics caused by Penicillium hirsutum, a total of 933 isolates (432 fungi and 501 bacteria) were isolated from the rhizoshere or rhizoplane of garlics. Among them, Pantoea agglomerans isolate 59-4 (Pa 59-4) was selected for a potential biocontrol agent by in vivo wounded garlic bulb assay, When the spore suspension (10$\^$5/ spores/$m\ell$) of Penicillium hirsutum was co-inoculated with spore or cell suspension of each fungal or bacterial isolate on wounded garlics, the isolate highly suppressed disease development. Soaking garlic bulbs in the suspension of Pa 59-4 significantly reduced garlic decay from p. hirsutum. However, Pa 59-4 did not inhibit the mycelial growth of P. hirsutum in dual-culture with P. hirsutum on Tryptic soy agar. In order to elucidate mode of action of Pa 59-4 nutrient competition between Pa 59-4 and P. hirsutum was investigated using tissue culture plates with cylinder inserts containing defusing membrane reported by Janisiewicz et al. The results showed that Pa 59-4 effectively suppressed spore germination and mycelial growth of blue mold in the low concentration (0.5％) of garlic juice, but did not suppress those of blue mold in the higher concentration (5％) of garlic juice. This result suggests that the mechanism in biocontrol of garlic blue mold by Pa 59-4 may involve in nutrient competition with P. hirsutum on garlic bulbs.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.113-120
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• 2022

Leaf blight disease caused by Stemphylium species is an important disease in Allium crops, specifically onion, garlic and welsh onion. In 2018, leaf blight symptoms were severe and damaged onion and garlic in Jeonnam province in Korea. In addition, small purple spots on garlic burbs were observed in a post-harvest storage warehouse. Several Stemphylium isolates were isolated from diseased leaves from the field and from garlic bulb samples and were analyzed in terms of homology and the phylogenetic relationship based on the internal transcribed spacer region and calmodulin gene sequence. The results showed that among three Stemphylium species identified, S. vesicarium is most prevalent on onion and garlic. S. eturmiunum was for the first time identified as pathogenic to onion and garlic, whereas S. solani was found in welsh onion crops. Although these isolates grew well at the optimum temperature at 20 - 25℃, they could also grow at low temperatures of 10 - 15℃. A pathogenicity test was conducted using S. vesicarium and S. eturmiunum on onion and garlic respectively. These results showed that two Stemphylium species were highly virulent with cross pathogenicity in onion and garlic. The results of this study can support the biological characterization of Stemphylium species in Korea. Moreover, further research will need to develop fungicide application strategies for onion and garlic crops.

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.299-303
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• 2008

An Oriental lily cultivar 'Pacific Wave' was released in 2007 at National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA), Suwon, Korea. The crossing was made in 1999 between Oriental lily 'Simplon', an outward-facing and white colored cultivar, and 'Spinoza', pink colored cultivar. The first selection was done in 2003 with a line of 'O-03-16'. Multiplication and bulb growth, and performance test was conducted from 2004 to 2006. This selection was later on given as 'Pacific Wave' in 2007 at NHRI. Flowering time of 'Pacific Wave' in plastics house culture is mid June and grows average 115 cm. Flowers are upward-facing with 20.1 cm in diameter and white with yellow centered (RHS W155C + Y9A). Mean petal length and width is 12.2 cm and 4.2 cm, respectively. Leaves are 12.3 cm long, 2.9 cm wide. The throat color is green. It shows gray and purple stigma, and red brown pollen. The weight and size of bulb is 82.5 g and 19.6 cm, respectively. Year-round flowering can be by storing the bulb under -1 to $-2^{\circ}C$ conditions. It is necessary to add calcium to the fertilizer or remove side scales to prevent leaf scorch. It is needed to control Botrytis disease in summer wet season.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.750-756
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• 2010

This study was performed to investigate the role of phytohormones in the bulbing of garlic in order to assess the yield and quality. The effect on endogenous plant hormones such as gibberellin (GA) content was also examined during growth stage i.e. clove differentiation to bulbing in garlic. More than 18 gibberellins in garlic were identified with extensive gas chromatograph-mass spectrometry-selected ion monitoring (GC-MS-SIM) quantitative analysis. The results showed that GAs were biosynthesized by both non C-13 hydroxylation pathway (NCH) and early C-13 hydroxylation pathway (ECH) in garlic plant. It was also revealed that NCH pathway leading to synthesis of bioactive $GA_4$ was the more prominent GA biosynthesis pathway than ECH pathway in which bioactive $GA_1$ was synthesized. Total GAs level was gradually increased from clove differentiation to bulbing and later decreased, which portrays the active role of GA in differentiation. The biosynthesis ratio of bioactive $GA_4$ and $GA_1$ concentration was similar to that of total GAs content, which was closely related with bulb development in garlic.