• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.2
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• pp.130-135
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• 1995

In this paper, the numerical simulation of the method of characteristics for a two-stroke SI engine was carried out, and the scavenging efficiency and the performance of single engine with two types of exhaust system, that is, a pipe exhaust system and a tuned exhaust system, were predicted and compared. The conculusions are obtained as follows. (1) The method of characteristics of hometropic flow considering the friction and the variation of area is useful to predict the scavenging efficiency and the performance of the two-stroke engine. (2) The shape of exhaust system effects directly on the scavenging and the trapping efficiency. (3) A tuned exhaust system consisted of the diffuser and the convergent nozzle makes the plugging pulse and therefore enhances the scavenging and the trapping efficiency. (4) It may be possible to design the optimum exhaust system by using the plugging pulse.

• Applied Microscopy
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• v.7 no.1
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• pp.13-20
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• 1977

The ultrastructures of hemocytes of Acrida cinerea Thunberg were studied and 4 types of hemocytes were noticed; prohemocytes, plasmatocytes, granular cells and adipohemocytes. Prohemocytes were the smallest of all cell types with poor cytoplasmic organelles, such as endoplasmic reticulum, Golgi complexes, vacuoles and Iysosomes. Plasmatocytes were round or oval with many cytoplasmic processes, vacuoles, endoplasmic reticulum and even myelinated bodies. Granular cells were spindle-shaped or oval. In both cases, they are characterized by various granules. Adipohemocytes were very rich in lipid droplets and microtublles.

• Journal of Power System Engineering
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• v.4 no.1
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• pp.39-44
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• 2000

The purpose of this study is to investigate the flame structure and combustion characteristics in the model gas turbine combustor changing equivalence ratio. For this purpose, temperature and ion current were measured and these data were analyzed by the PDF and power spectra technique. We found that the flame length is longer while increasing the equivalence ratio in experimental condition, and especially ${\psi}=0.19$, combustion reaction was active by the stable swirl flow. and these flames were governed by the random three dimensional eddy.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.614-615
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• 2010

The propellants distribution of an oxidizer rich preburner was predicted by a simplified physical approach. The Mixing head is composed of honeycomb array of 7 fuel injectors and 24 oxidizer injectors. The OF ratio of the mixing head is 15. As results, the OF ratio of the central area is about 9 and the OF ratio of the wall area is about 30.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1830-1834
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• 2004

In this paper, we present scavenge characteristics in a small subchamber of HCCI. It is very important to enhance scavenge rate because ignition in a chamber sometimes does not happen. To understand this phenomenon numerical tool was performed using the FLUENT which is a commercial code. Focus is given to the effect on the scavenge rate of the geometric factor that is the angle of nozzle injection. The numerical results show that the scavenge ones in the subchamber heavily depend on the nozzle angle. It was found that the scavenge rate is more effective at angled nozzle.

• The Korean Journal of Zoology
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• v.38 no.1
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• pp.38-47
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• 1995

담수에서 해수로 이동하는 동안 환경의 변화에 적응하는 표피의 점액세포와 곤봉상세포의 구조적 기능적 적응기작을 연구하기 위하여 성숙한 뱀장어를 이용하여 본 실험을 행하였다. 높은 염농도로 외부환경이 변화함에 따라 뱀장어의 점액세포와 곤봉상세 포에서 능동적으로 대응하는 여러 현상들이 나타났다 포피전층에 점액세포의 수가 증가하였으며, 점액세포내에서의 세포소기 관이 활성화 되어 활발히 표피외분비를 하는 것이 관찰되었으며, 기저상피세포층과의 경계부위에서 나타나는 미성숙형 점액세포가 성숙형으로 바뀌는 현상이 나타나는 것으로 보아 표피의 점액질량을 증가시키는 것을 알 수 있었다 그리고 곤봉상세포에서도 염분증가에 따라 세포소기 관의 발달을 관찰할 수 있었으며, 중심포에서의 전자염색성의 변화와 함께 집합소포의 수가 증가하며, 중심포가 세분화되어 크기가 작아지는 현상을 관찰하고 그 기능적 의의에 대하여 논의하였다.

• Parasites, Hosts and Diseases
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• v.29 no.4
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• pp.407-410
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• 1991

A 35-year-old housewife living in Seoul complained of a recurrent palpable abdominal mass. Excisional biopsy was done. The cystic mass showed an immature worm of Paragonimus sp. in the cyst cavity. It measured $7{\times }4{\;}mm$ and showed well-developed oral and ventral sucker, uterus, 5-branched ovary and intestine after acetocarmine staining. But the testes and vitelline duct were not developed fully and there was no egg in the uterus. The patient has eaten raw fish. The case of ectopic paragonimiasis in the abdominal subcutaneous tissue was presented.

• 대학교육
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• s.135
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• pp.66-73
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• 2005

우리는 그간 정부 주도의 대학개혁이 소기의 성과를 달성하지 못하고 실패로 끝났던 역사적 사실을 상기해 볼 때 새로운 패러다임은 누군가의 강요가 아닌 구성원들의 합의와 공감대가 형성되었을 때 가능함을 분명히 각인해야 한다.

• 대학교육
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• s.137
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• pp.7-11
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• 2005

산학협력에 있어 중앙정부와 지방정부의 정책적 지원은 더욱 강화되어야 하며, 대학은 경쟁력있고 특성화된 산학협력 모델을 다양하게 개발하여야 하고, 대학과 기업 간의 신뢰 구축과 상호 이해의 폭을 획기적으로 넓혀 나가야 대학의 산학협력단은 소기의 목적을 달성할 수 있다.

• Transportation Technology and Policy
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• v.9 no.2
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• pp.77-85
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• 2012