• Journal of Advanced Marine Engineering and Technology
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• v.27 no.5
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• pp.624-632
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• 2003

In the gasoline engine industry. there has been a trend towards the development of high performance engines with improved fuel efficiency, reduced weight and smaller sizes. These trends help to solved engine problems related to thermal load and abnormal combustion. In order to investigate these Problems, a thin film-type probe for instantaneously measuring temperatures has been suggested. A method for manufacturing such a probe was established in this study. The instantaneous surface temperature of a constant volume combustion chamber was measured by this probe and the heat flux was obtained through Fourier analysis. A peak instantaneous temperature was obtained after 55∼60 ms from ignition and the temperature increased according to an equivalence ratio and varied differently according to the position of the probe. Total heat loss during combustion period was affected by the equivalence ratio and differed widely in accordance to the position of the probe.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.2
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• pp.265-273
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• 2003

Numerical analysis of bubble motion during nucleate boiling is performed by imposing a constant heat flux condition at the base of a heater which occurs in most of boiling experiments. The temporal and spatial variation of a solid surface temperature associated with the bubble growth and departure is investigated by solving a conjugate problem involving conduction in the solid. The vapor-liquid interface is tracked by a level set method which is modified to include the effects of phase change at the interface, contact angle at the wall and evaporative heat flux in a thin liquid micro-layer. Based on the numerical results, the bubble growth pattern and its interaction with the heating solid are discussed. Also, the effect of heating condition on the bubble growth under a micro-gravity condition is investigated.

• Journal of Veterinary Clinics
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• v.33 no.3
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• pp.179-182
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• 2016

An 11-year-old castrated male Maltese had vomiting, diarrhea, and abdominal distension for over two weeks and weight loss for several months. Clinical laboratory studies were not remarkable. Abdominal radiographs showed severe dilated intestine with a gravel sign. Colon was empty with normal diameter in the pneumocolon study. On ultrasonographs, most small bowel loops were dilated without normal peristalsis and showed abnormal thin wall. Barium contrast study revealed remarkably delayed gastric emptying and transit time up to $6^{th}$ day. On exploratory laparotomy, there were no mechanical obstruction and extra-intestinal abnormalities except severe dilated small intestine. Chronic fibrosing lymphohistiocytic leiomyositis with atrophy of tunica muscularis in the small intestines and colon was identified through full thickness biopsy and histopathology. Therefore, primary myopathic chronic intestinal pseudo-obstruction was diagnosed. This dog is survival with symptomatic treatments for eight months.

• The Microorganisms and Industry
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• v.20 no.1
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• pp.50-52
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• 1994

Ultrastructural observations of mycelial and tissue phase with dimorphic fungal pathogen Coccidioides immitis were studied by electron microscopy of thin sections. 1. In mycelial phase of C.immitis contains normal cell components such as nucleus, mitochondria, endoplamsic reticulum, intracytoplasmic membrane system, cell wall and cell membrane as observed in the other encaryotic cells. 2. In tissue phase of C. immitis was larger than mycelial phase in cell size and observed much more vacuoles than mycelial phase. 3. In the contrast of mycelial phase of C. immitis, the tissue phase of cells were observed fibril form of capsular layer.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.238-240
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• 1991

Langmuir-Blodgett(L.B) method is one of the most possible candidate for the fabrication of the micro scale memory or electrical devices. As for a fundamental study on the conduction mechanism in the organic thin membrane, N-alkyl quinolium-TCNQ complexes were synthesized and their physical properties were examined spectroscopically. LB film was produced by using Moving Wall Type LB Apparatus. The average area per molecule (N-docosylquinolium-TCNQ) was $67.97{\AA}^2$ which is ${\AA}^2$ larger than N-docosyl quinolium-TCNQ.

• Korean Journal of Microbiology
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• v.9 no.4
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• pp.169-174
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• 1971

Ultrastructural observations of mycelial and tissue phase with dimorphic fungal pathogen Coccidioides immitis were studied by electron microscopy of thin sections. 1. In mycelial phase of C.immitis contains normal cell components such as nucleus, mitochondria, endoplamsic reticulum, intracytoplasmic membrane system, cell wall and cell membrane as observed in the other encaryotic cells. 2. In tissue phase of C. immitis was larger than mycelial phase in cell size and observed much more vacuoles than mycelial phase. 3. In the contrast of mycelial phase of C. immitis, the tissue phase of cells were observed fibril form of capsular layer.

• Nuclear Engineering and Technology
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• v.29 no.2
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• pp.175-180
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• 1997

It has been known that eater-side corrosion of fuel rods in nuclear reactor is accompanied with the metallic loss of wall thickness and hydrogen pickup in the fuel dadding tube. The fuel dad corrosion is one of the major factors to be controlled to maintain the fuel integrity during reactor operation. An oxide later thickness measuring device equipped with ECT probe system was developed by KAERI, and whose performance test was carried out in NDT(Non-destructive Test) hot-cell or PIE(Post Irradiation Examination) Facility. At first, the calibration/performance test was executed for the unirradiated standard specimen rod fabricated with several kinds of plastic thin films whose thickness ore predetermined, and the result of which showed a good precision within 10% of discrepancy. And then, hot test us peformed for the irradiated fuel rod selectively extracted from J44 fuel assembly discharged from Kori Unit-2. The data obtained with this device were compared with the metallographic result obtained from destructive examination in PIEF hot-cell on the same fuel rod to verify the validity of the measurement data.

• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.280-283
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• 2011

In the present work, a new approach is proposed for via interconnects of semiconductor devices, where multi-wall carbon nanotubes (MWCNTs) are used instead of conventional metals. In order to implement a selective growth of carbon nanotubes (CNTs) for via interconnect, the buried catalyst method is selected which is the most compatible with semiconductor processes. The cobalt catalyst for CNT growth is pre-deposited before via hole patterning, and to achieve the via etch stop on the thin catalyst layer (ca. 3nm), a novel 2-step etch scheme is designed; the first step is a conventional oxide etch while the second step chemically etches the silicon nitride layer to lower the damage of the catalyst layer. The results show that the 2-step etch scheme is a feasible candidate for the realization of CNT interconnects in conventional semiconductor devices.

• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.233-238
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• 2011

In the present work, a new approach is proposed for via interconnects of semiconductor devices, where multi-wall carbon nanotubes (MWCNTs) are used instead of conventional metals. In order to implement a selective growth of carbon nanotubes (CNTs) for via interconnect, the buried catalyst method is selected which is the most compatible with semiconductor processes. The cobalt catalyst for CNT growth is pre-deposited before via hole patterning, and to achieve the via etch stop on the thin catalyst layer (ca. 3nm), a novel 2-step etch scheme is designed; the first step is a conventional oxide etch while the second step chemically etches the silicon nitride layer to lower the damage of the catalyst layer. The results show that the 2-step etch scheme is a feasible candidate for the realization of CNT interconnects in conventional semiconductor devices.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.532-537
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• 2007

Nano imprint lithography(NIL) is a cost-efficient, high-throughput processing technique to transfer nano-scale patterns onto thin polymer films. Polymers used as the resist include UV cured resins as well as thermoplastics such as polymethyl-methacrylate(PMMA). In this study, an analytic investigation was performed for the NIL process of transferring nano scale patterns onto polymeric films. Process optimization calls for a thorough understanding of resist flow during the process. We carried out 2D and 3D numerical analyses of resist flow during NIL process. The simulation incorporated continuum-hypothesis and the effects of surface tension were taken into account. For a more effective prediction of free surface, fixed grid scheme with the volume of fluid (VOF) method were used. The simulation results were verified with experimental results qualitatively. And the parametric study was performed for various process conditions.