• KSBB Journal
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• v.11 no.5
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• pp.586-592
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• 1996

Poly(3-hydroxybutyric-co-3-hydroxyvaleric) acid(PHB/HV) copolymer synthesis by Pseudomonas sp. HJ from glucose and cosubstrate was investigated. Taxonomic analysis suggested that Pseudomonas sp. HJ was best marched to Pseudomonas picketti having 78.8% similarity. Pseudomonas sp. HJ produced PHB/HV copolymer containing 60.8 mol% HV and 44.9 mol% HV when supplied with hexadecane and propionic acid as a cosubstrate, respectively. The HV composition in PHB/HV copolymer was controlled by varying the concentration of hexadecane and propionic acid. Propionic acid added after 24 hours of incubation was incorporated as the HV monomer in the PHB/HV copolymer up to 49.6 mol%.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.595-602
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• 2017

In Korea, much research and development have occurred to enhance the technological competitiveness of tuna purse seining fisheries. Due to these efforts, fishing efficiency has been improved with the development of radar, sonar and global positioning systems for fish detection and revisions to the hull forms of tuna purse seiners. However, for skiff boats, net boats and speed boats, which are auxiliary working boats mounted on tuna purse seiners, technology has lagged behind relative to the modernization of the main vessel. In this study, the hull of an existing propeller-based net boat with steel wire net to protect tuna was changed to the hull of a water jet propulsion vehicle to reduce resistance and improve maneuverability. As a result, a prototype of a water jet propulsion option was produced according to the aluminum structure strength standards specified by the Ministry of Oceans and Fisheries, and safety was confirmed by performing a drop test. Moreover, through a sea trial test, an existing net boat was shown to have a speed of 12.0knots and a towing force of 2,545 kgf at 2,500 RPM. The prototype had a speed of 26.7 knots and a towing force of 2,011 kgf at 3,200 RPM, which satisfied the towing capacity standards of auxiliary working boats mounted on tuna purse seiners.

• Journal of Korea Multimedia Society
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• v.14 no.3
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• pp.348-355
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• 2011

In this paper, we propose an automatic prostate segmentation method from dynamic magnetic resonance (MR) images. Our method detects contrast-enhanced images among the dynamic MR images using an average intensity analysis. Then, the candidate regions of prostate are detected by the B-spline non-rigid registration and subtraction between the pre-contrast and contrast-enhanced MR images. Finally, the prostate is segmented by performing a dilation operation outward, and sequential shape propagation inward. Our method was validated by ten data sets and the results were compared with the manually segmented results. The average volumetric overlap error was 6.8%, and average absolute volumetric measurement error was 2.5%. Our method could be used for the computer-aided prostate diagnosis, which requires an accurate prostate segmentation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.1
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• pp.63-68
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• 2006

Time series of waterline changes during a flood/ebb cycle can be utilized for supplementary data for measuring bottom topography. The waterlines extracted from consecutive images are substituted for depth contours using water level data. The distances between contours are quantified through a rectification image process. This technique is applied to the Keunpoolan beach in the Daeijak Island near Incheon. A camera monitoring technique supported by natural water level changes produces bottom topography with high precision. It is also less time consuming and more economical. The technique also can be utilized effectively to the physical modeling f3r measuring bottom changes in the three dimensional basin.

• Explosives and Blasting
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• v.21 no.3
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• pp.1-10
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• 2003

터널굴착발파공법의 하나인 V-cut발파공법은 터널굴착기술이 발전되는 과정에서 초기에 개발되어진 기술이나 작업의 간편성과 효율성으로 인하여 많은 터널굴착공사에서 이용되고 있는 발파공법이다. V-cut발파공법은 일자유면 상태에서 V형으로 심발공을 발파하고 심발공에 의해 형성된 자유면을 이용하여 확대공으로 굴착공간을 넓히는 발파 방법이며 심발발파의 굴진장에 의해 단일발파당 굴진장이 결정된다. V-cut발파법이 개발된 이래 V-cut발파의 굴진장을 증대시키기 위한 방법으로 심발발파공의 구속저항을 감소시키기 위해 보조심발공을 발파하여 형성된 자유면에 의해 심발공의 최소저항선거리를 줄여 발파하였으나 심발공의 구속저항이 감소되지 않아 발파효율이 증대되지 않았으며 발파진동 또한 가장 크게 발생하였다. 이와 같은 현상은 최소저항선거리의 감소효과에 대한 발파기술상의 이론에 문제가 있기 때문이다. 본 연구에서는 V-cut발파법의 심발공에 대한 구속저항감소효과가 발현될 수 있는 조건들을 검토하여 최소저항선거리의 감소효과가 발현될 수 있는 조건을 제시 하여 심발공의 발파효율을 증대시키고 발파진동이 적어지는 발파방법을 제안하려 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.658-663
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• 2008

In this study, we estimated the influence of electrical pole by FEM(Finite Element Method) and developed protective system by designing and interpreting protective system for electrical pole and overhead optical communication line when abnormal strength worked on messenger wire. Protective system did not shed messenger wire under wind pressure and discontent load but did assign a part to preventing rupture of electrical pole and disconnection of optical communication line through automatically shed messenger wire over fixed strength. Structure of protective system analysis by FEM and prove property by measuring tensile strength for practical product.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.12
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• pp.2241-2248
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• 2017

The coaxial line impedance transformer that performs impedance conversion using the coupling of two or more coaxial lines of the same length is often used for impedance matching in the low frequency region due to many advantages. This paper measures the phase and magnitude characteristics of each coaxial line in a 4:1 coaxial line impedance transformer using two 100mm coaxial lines. This experiment shows that it is more effective to make the length of the auxiliary coaxial line shorter than the main coaxial line by about 5 mm in order to realize a low loss impedance transformer. In addition, it measures the transmission characteristics by directly connecting a 4:1 impedance transformer and a 1:4 impedance transformer. This experiment shows that it is effective to connect a 1pF capacitor between the ground and the outer conductor input point of the main coaxial line in order to increase the operating frequency range.

• ETRI Journal
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• v.9 no.4
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• pp.58-71
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• 1987

No.7 신호방식은 종합정보통신망에서 음성 및 비음성의 회선교환 서비스를 제공하기 위한 국간 신호방식 기능을 수행할 뿐만 아니라, 망을 지능화하고 여러가지 보조서비스들을 제공하며 망을 보다 효율적으로 운용 관리하기 위하여 통신망내의 프로세서들 간에 사용되는 범용적 데이터 통신 프로토콜로서, 디지틀 가입자-망 액세스와 함께 종합정보통신망을 실현하기 위해 필수적으로 요구되는 새로운 신호방식이다. 본 고는 최근의 CCITT 연구결과를 바탕으로 종합 정보통신망과 비관련된 전화사용자부(Telephone User Part)와 데이터 사용자부(Data User Part) 를 제외한 전반적 No. 7 신호방식에 대하여 기술한다. 더불어 이러한 No. 7 신호방식이 운용되는 공통선 신호망에 대하여 간략히 설명한다.

• The Microorganisms and Industry
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• v.19 no.3
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• pp.46-48
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• 1993

현재 유산균은 요구르트, 치즈, 케피어(kefir), 에시도필러스 밀크(acidophilus milk), 비피더스 밀크(bifidus milk), 쿠미스(kumiss), 발효버터(fermented butter), 유산균음료, 빵 등 식품의 천연 방부제, 채소절임, 발효두유(fermented soy milk), 정장제, 구강염증치료제, 사료 첨가제 등등 다양하게 이용되고 있다. 이것은 유산균에 대한 동결건조, 유전자 조작 등 첨단기술이 산업화로 연결되면서 그 이용성이 더욱 확장되고 있다. 유산균을 이용한 건강보조식품도 최근 몇년 사이에 선을 보이고 있지만 아직은 초보적인 단계이며 현재로선 유산균 발효식품과 유산균제제(의약품) 사이에서 뚜렷한 자기자리를 찾지 못하고 있는 실정이다.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.658-660
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• 2005

본 논문에서는 한전 22.9kV 배전선로의 고장전류 및 선로손실 계산의 기초 자료로 활용하고 있는 배전선로 선종별 임피던스 값을 EMTP를 사용하여 계산하였다. EMTP와 그 보조 프로그램인 LINE CONSTANTS와 CABLE CONSTANTS의 간단한 계산 원리와 근거들을 각 항목들별로 자세히 기술하였다. 각 선종별로 기하학적 위치와 물리적은 제정수를 사용하여 계산을 하였으며, 가변 가능한 변수들은 모두 조정하여 상호 비교하였다.