• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.7
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• pp.549-556
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• 2001

Heat flow characteristics during hot water extraction process was studied experimentally. Data were taken at various outlet port type for the fixed inlet port type, inlet-outlet temperature differences and mass flow rates. In this study, the temperature distribution in a storage tank and an outlet temperature were measured to predict a flow pattern in the storage tank, and a hot water extraction efficiency was analysed with respect to the variables dominating a extraction process. Experimental results show that the extraction efficiency is high in a low flow rate in case of using modified distributor I(MDI) as a outlet port type.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.557-560
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• 2006

The contact angle of a meniscus and a droplet can be controlled by using electrowetting phenomena. We investigated the dynamic aspect of electrowetting for an oil-electrolyte interface formed inside a closed glass tube. A step input voltage is applied and the subsequent motion of the interface is recorded by a high-speed camera. A kind of capillary instability is observed near the three-phase contact line, which could degrade the reliability of device utilizing electrowetting such as electrowetting liquid lens. The dynamics of interface motion for different input voltages and the fluid viscosities are analyzed and discussed based on the experimental results.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.49-51
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• 2001

현재까지의 고교배정은 지망배정과 무작위배정 방식을 이용한 배정방식으로 원거리 통학자가 다수 발생하는 등의 문제가 있다. 이러한 문제를 해결하기 위해 본 논문에서는 GIS의 네트워크 분석기능에 의해 계산된 학교와 학생간의 도로중심의 거리를 이용하여 원거리억제지향의 배정방식을 도입하였다. 본 논문에서 구현한 시스템을 울산지역에 적용한 결과, 근거리 배정 방식에 의해 배정된 학생(5318명)중 82.39%(4799)가 6Km미만의 근거리, 17.36%(1011명)가 6Km~18Km의 중거리, 0.25%(15명)가 18Km이상의 원거리로 배정되었다. 상기의 시스템은 학생 및 학교의 주소에 대한 자동주소맵핑기능, 학생과 각 학교에 대한 최단 거리의 자동생성, 학교의 정원초과에 의해 불가피하게 발생하는 원거리 학생을 최대한 억제하기 위한 방법 등을 고려하여 설계되었다.

• The KSFM Journal of Fluid Machinery
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• v.13 no.5
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• pp.54-57
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• 2010

The purpose of this article is to diagnosis all aspects of waste pneumatic transportation system, in order to provide everyone interested in the subject with a optimal design and management of the system. The results of the analyzed inlet boxes were especially designed for customers' convenience and automatically operation, side air intake, ensure good wear. And key of pipelines were showed design standard as degree of an angle. Also, the system is mostly equipped with automatic control and watch conducted inside the waste collection facilities, and it will cut down excessive manpower and be able to be managed by least trained personnel.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.6
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• pp.503-511
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• 2002

Heat flow characteristics during hot water extraction process was studied experimentally. Data were taken at various outlet port type for the fixed inlet port type, inlet-outlet temperature differences and mass flow rates. In this study, the temperature distribution in a storage tank and an outlet temperature were measured to predict a degree of stratification in the storage tank, and a useful rate of hot water was analysed with respect to the variables dominating a extraction process. Experimental results show that the degree of stratification and useful rate of hot water are all high in a low flow rate in case of using modified distributor I (MDI) as the outlet port type.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.619-620
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• 2019

도서관에서 사용자들이 책을 빌리거나 반납하기 위해서는 'ㄱ'부터 시작하여 'ㅎ'까지 순서대로 진열이 되어 있는 책의 위치를 찾아가야 한다. 책을 반납할 때, 책을 다시 제자리에 놓는다면 문제가 없지만 사람들이 책을 읽고 진열대에 다시 넣는 과정에서 착오가 생겨, 다른 진열대 넣는 경우, 도선관 사서가 이를 찾아내, 올바른 위치에 놓아야 한다. 또한, 사용자들이 반납한 책들을 도서관 사서가 실수로 다른 곳에 진열할 수도 있다. 본 논문에서는 이러한 문제점을 줄이기 위해, 지능형 모바일 증강현실에 기반한 도서 위치 관리 방법을 제시한다. 제시된 방법에서는 책의 위치 정보, 각도 등 다양한 센싱 정보를 활용하여 진열된 책들이 제자리에 있는지를 실시간으로 점검하고 책의 위치가 잘못 되었을 경우, 도서관 사서에게 이를 알려 책의 위치를 바로 잡도록 하였다.

• Journal of Applied Reliability
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• v.7 no.3
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• pp.127-136
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• 2007

The accelerated life tests(ALTs) and degradation characteristics of image intensifier assembly(KIT-7) under low illuminance and high temperature were investigated. The accelerated life tests were carried out at $5{\times}10^5\;fc-40^{\circ}C,\;10{\times}10^5\;fc-40^{\circ}C,\;5{\times}10^5\;fc-50^{\circ}C,\;10{\times}10^5\;fc-50^{\circ}C$ and relationship related to illuminance and temperature was used as an accelerated life test model. An ALTA program[6] was used to calculate an acceleration factor and the test of life distribution fit, and estimate three parameters of an life test model. To sum up, MTTF 10,000 h at $5{\times}10^{-5}\;fc-40^{\circ}C$ of image intensifier assembly was certificated.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.711-716
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• 1996

발전소 정상운전 및 정지기간 중 2차측 급수를 통하여 증기발생기 안으로 불순물이 유입되며, 운전중에 과열도가 높은 중기발생기 세관과 튜브쉬트등의 틈새에는 불순물의 농축도가 심해지며 이로인해 전열관이 부식손상을 입는다. 잠복불순물은 출력감발 및 정지기간 중에 증기발생기 급수의 냉각에 따라 불순물의 용해도차로 인해 재방출된다. 본 연구에선 89년부터 94년사이에 행하여진 원전 현장의 잠복불순물 방출시험자료를 이용하여 데이터베이스를 작성하였으며, 이중의 일부를 입력자료로 사용하여 Framona 전산코드작업을 수행한 결과 틈새의 pH 변화를 년도별로 비교할 수 있었다. 비교결과 년도가 지날 수록 증기발생기의 틈새에서의 pH는 낮아짐을 볼 수 있었으며 현장의 년도별 증기발생기 세관 관막 음수 증가 경향과 잘 일치하였다.

• Applied Microscopy
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• v.33 no.3
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• pp.243-250
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• 2003

Ultrastructural changes of the male germ cells and structure of spermatozoa in Paralichthys olivaceus were examined by means of the light and transmission electron microscopes. The spermatogonium has a large nucleus with a single nucleus with a single nucleolus in the interphase. Primary spermatocytes are identified by the formation of the synaptonemal complex in the karyoplasm. The secondary spermatocytes are more concentrated and contains numerous cell organelle in the cytoplasm. The nucleus of spermatid in spermiogenesis is more condensed in the karyoplasm, and show spherical structure in shape. Mitochondria of the spermatids are observed in the lower portion of the nucleus. The spermatozoon consists of the head, mid piece and tail. The acrosome is not observed in the head. Axial filaments of the flagellum consists of nine pairs of the peripheral microtubules and one pair of the central microtubules.

• Journal of Aquaculture
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• v.13 no.3
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• pp.215-222
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• 2000

The primordial germ cell of the sweet fish was recognized from the 2-day old fry (tl : 0.66 cm), when it began to protrude into peritoneal cavity between meaonephric duct and gut. The primordial gonad, with the formation of genital ridge, developed on the 30-day old fry. Ovarian differentiation was identified by the presence of ovarian cavity and meiotic oocytes from the 90-day old fry (tl : 3.42 cm). Testicular differentiation was identified by the presence of spermatogonial cells with efferent duct from the 100-day old fry (11 : 4.50 cm). Hence the sweet fish belongs to the differentiated type of gonochoristic teleost.