• Journal of computational fluids engineering
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• v.17 no.1
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• pp.36-43
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• 2012

When a high-speed train passes an underground station, large pressure waves are generated due to the piston effect. These pressure waves can cause the problems of vibration and noise as well as the ear discomfort of passengers at the underground station. This work numerically analyzed the pressure wave generation and propagation in an high-speed railway underground station, and the optimal location for vent shafts was studied to improve the passenger comfort by reducing the magnitude of the pressure wave and its rate of change. The evolution of pressure field in the underground station was calculated using a CFD(Computational Fluid Dynamics) software(Fluent), where the axis-symmetric two-dimensional model verified by Wu was used. And this study is applied to modelling of the underground station and the tunnel from Daegok station A-line of GTX(Great Train Express). From the result, we can have a conclusion that the role of vent shafts respectively were different according to the position in and out the underground station. Also Vent shaft in the underground station widely reduced pressure magnitude. And vent shaft out underground station reduced initial pressure peak value. Double vent shafts installed at tunnel toward station entrance and inside of the tunnel are the most efficient to reduce pressure. and pressure reduction increases according to the number of vent shaft.

• Bulletin of the Society of Naval Architects of Korea
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• v.24 no.3
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• pp.17-24
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• 1987

The present paper describes the results of the cooperative experimental study organized by the Resistance Committee of the Korea Towing Tank Conference, which aims to improve model testing technique and accuracy and to self-evaluate their own capabilities. A Series 60, $C_b=0.60$ model was tested at the towing tanks of Korea Institute of Machinery & Metals, Hyundai Maritime Research Institute, Seoul National University, and Inha University. Results for total resistance, wave pattern analysis, wave pattern analysis, wave profile, trim & sinkage and wake measure ments are presented.

• Journal of Genetic Medicine
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• v.19 no.1
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• pp.14-21
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• 2022

Complex chromosome rearrangements (CCRs) are structural chromosomal rearrangements involving at least three chromosomes and more than two breakpoints. CCR carriers are generally phenotypically normal but related to higher risk of recurrent miscarriage and having abnormal offspring with congenital anomalies. However, most of CCR carriers are not aware of their condition until genetic analysis of either abortus or affected baby or parental karyotyping is performed. Herein, we present the case that CCR carrier patients can be identified by preimplantation genetic testing of preimplantation embryos. An infertile male patient with severe oligoasthenoteratozoospermia was diagnosed balanced reciprocal translocation, 46,XY,t(3;11) (p26;p14) at first. After attempting the first preimplantation genetic testing for structural rearrangement (PGT-SR) cycle, we found the recurrent segmental gain or loss on 21q21.3-q22.3 of five out of nine embryos. As a result of karyotype re-analysis, the patient's karyotype showed a balanced CCR involving chromosomes 3, 11, and 21 with three breakpoints 3p26, 11p14, and 21q21. The patient underwent two PGT-SR cycles, and a pregnancy was established after the transfer of an euploid embryo in the second cycle. Amniocentesis confirmed that the baby carried normal karyotype without mosaicism. At 37 weeks gestation, a healthy girl weighting 3,050 g was born.

• Journal of the Korean association of regional geographers
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• v.15 no.6
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• pp.789-802
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• 2009

The purpose of this study is to reveal general features and toponymical characteristics of station names of Seoul metropolitan railway system. Principal results of this study are as follows. At the present time of December, 2009, the number of station which is run is 508, the number of transfer station is 61 and the number of station which has another name is 89. Two-letter station names are 61.99%, and three-letter station names are 20.59%. Geographical names used as station name are classified into three types : administrative, physical, and human placename. In the three types, administrative placename is the most and physical placename is the least. In the administrative placename, the name of 'Dong' is the most. In the physical placename, the name of mountain is the most. In the human placename, the name of facilities is the most.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.387.4-388
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• 2001

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.05a
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• pp.55-55
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• 2003

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.142-143
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• 2003

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.238-239
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.152-153
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• 2000

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.78.2-78
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• 1999