• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.6 s.237
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• pp.696-702
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• 2005

The effect of incidence angle on the endwall heat (mass) transfer characteristics within a turbine rotor cascade passage has been investigated by employing the naphthalene sublimation technique. The experiments are carried out at the Reynolds number of $2.78{\times}10^5$ for two incidence angles of -5 and 5 dog. The result shows that the incidence angle has a considerable influence on the transport phenomena over the endwall. The positive incidence angle tends to promote development of the pressure-side leg of a leading-edge horseshoe vortex. The endwall thermal load is augmented by 7.5 percents at i = -5 deg but is reduced by 2.5 percents at i = 5 deg, in comparison with that at the design condition.

• Journal of Korean Society of Steel Construction
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• v.8 no.3 s.28
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• pp.107-116
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• 1996

The studies are conducted to investigate the fatigue and fracture, behavior of preflex girder. In this work, the fatigue tests using by constant amplitude fatigue loading and 4-point-loading to maintain pure bending condition in the mid-span of preflex girder will be performed. It is expected from the results of the studies to provide the fatigue strength and the S-N curve of preflex girders. In addition, it will be ensured that fracture initiation occurs in the welded part of horseshoe-type shear connector as well as in other welded joints.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2002.11a
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• pp.138-138
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• 2002

A 10-day old male calf exhibited multiple congenital anomalies of the urinary and gastrointestinal tracts, including renal fusion (horseshoe kidney), ureteral fusion, rectovesicular fistula, and atresia ani. The single kidney was fused at the caudal poles. The left kidney and cranial half of right kidney were shrunken, while the remaining lobules were hypertrophic. Ureters were fused cranially and bifurcated caudally. The terminal rectum was narrowed and connected with the bladder. The anus was imperforate. The cause of these anomalies could not be determined. This is the first report of this constellation of congenital anomalies in a calf.

• Explosives and Blasting
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• v.14 no.2
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• pp.63-70
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• 1996

This paper describes the method used to determine the optimal section for the horseshoe shaped single tunnel which is utitized widely in constructing subway tunnels. Vehicle and structural gauges conform to the design criteria for the Seoul Subway Line 5. The tunnel sections are determined considering the structural stability, and the tunnel excavation area is optimized so as to minimize design and construction costs.

• Animal cells and systems
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• v.8 no.4
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• pp.235-245
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• 2004

Numerous specimens of adults and juveniles of Draconema japonicum Kito, 1976 have been found in intertidal and subtidal sediments and various algae around coast of South Korea. Draconema japonicum is recognized by the following characteristics: having an elongated loop-shaped amphideal fovea in male and horseshoe-shaped amphideal fovea in female, two pairs of uniformly tapered sublateral anal setae and two pairs of unevenly tapered subventral anal setae in male, eight to ten pairs in male and 13 to 15 pairs in female of posterior sublateral adhesion tubes, and five to six pairs of somatic setae on non-striated tail region. Scanning electron photomicrographs of the species are presented with a detailed morphological description and a key to the species of the genus Draconema Cobb, 1913. This is the first discovery of D. japonicum outside the Japanese waters.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.29-50
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• 2002

Based on the investigation results on the damages of some underground structures due to the severe Kobe Earthquake it concludes that the aseismicity of underground is far superior to that of aboveground structures. Therefore, at first, necessity to reconstruct strong cities especially by good use of underground space will be discussed. Then two non-circular shield-tunneling projects in Japan are discussed. The first is construction of the world's first shield driven double track subway tunnel of rectangular shape for the Kyoto Municipal Subway. This paper presents a report on the overall planning, the tests that were performed in the process of planning, and the results of driving. The second is the design of the Hirakata Tunnel, with three traffic lanes and shoulders on one side, which will be constructed as one of the tunnels for The New Meishin (Nagoya-Kobe) Expressways. This paper presents the feasibility study of the shield tunneling method, using the same design criteria as the non-circular, horseshoe section of mountain tunnel, to the equivalent section of the Hirakata Tunnel.

• Wind and Structures
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• v.10 no.2
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• pp.135-151
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• 2007

This paper examines the extreme gust profiles obtained by conditionally sampling full-scale velocity data obtained in the lower part of the atmospheric boundary layer. It is demonstrated that three different types of behaviour can be observed in the streamwise component of velocity. In all cases the corresponding vertical velocity component illustrates similar behaviour. An idealised horseshoe vortex model and a downburst model are investigated to examine if such structures can explain the behaviour observed. In addition, an empirical model is developed for an isolated gust corresponding to each of the three types of behaviour observed. It is possible that the division of the gust profile into three different types may lead to an improvement in the correlation of extreme gust events with respect to type.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.1
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• pp.37-50
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• 2022

The use of uncertain names for imported crustaceans causes considerable confusion for the establishment of government policies and the public market. Therefore, there have been demands for reestablishment of the domestic names of imported fish to correct the market order and to prevent damage caused by confusion among consumers. A total of 118 species of imported fisheries crustaceans were reviewed (47 crab spp., 36 shrimp spp., 27 lobster and crayfish spp., five mantis shrimp spp., and three horseshoe crab spp.). Although not belonging to the Subphylum Crustacea, three species of the Subphylum Chelicerata and five species of the Order Stomatopoda were included for review. Of these, 49 species that require Korean name assignment and reexamination of domestic names were selected and Korean names were assigned.

• Communications of the Korean Mathematical Society
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• v.38 no.1
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• pp.21-38
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• 2023

Let R be a commutative ring with identity. Let R be an integral domain and M a torsion-free R-module. We investigate the relation between the notion of e-exactness, recently introduced by Akray and Zebari [1], and generalized the concept of homology, and establish a relation between e-exact sequences and homology of modules. We modify some applications of e-exact sequences in homology and reprove some results of homology with e-exact sequences such as horseshoe lemma, long exact sequences, connecting homomorphisms and etc. Next, we generalize two special drived functor T or and Ext, and study some properties of them.

• Journal of Korean Elementary Science Education
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• v.26 no.4
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• pp.440-448
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• 2007

The purpose of this study is to examine elementary students' conceptions of magnetic fields around various magnets by drawing tasks. A total of 105 elementary students from the 3rd and 6th grade levels were asked to draw how iron filings would arrange around magnets. We classified their drawings of magnetic field lines with some criteria to identify conceptions of magnetic forces and checked them through interviewing about their representative drawing. Through analyzing drawings, we discovered that 40% of elementary students drew the correct arrangement of iron filings around a bar magnet. In the case of two bar magnets in opposite directions, 33% of them drew correct patterns of iron dust and around two magnets in the same direction only 20% did well. Only 2.9% and 7.6% of students presented the correct drawings of magnetic fields near a disc and a horseshoe magnet. While 3rd grade students were supposed to be poor in drawings of magnetic fields around a loose and a dense coil which was not learned about, only 31% and 23% of 6th grade students who have just studied electromagnetism properly drew patterns of iron dust. This shows that only one quarter of students understood the magnetic filed lines even after instruction of electromagnetism. Many of 6th grade students learned a solenoid becomes just as a permanent magnet, but very few of them correctly drew a magnetic field line could distinguish between the iron dust around a loose and dense coil. After interviewing students, it is found that students consider magnetic forces to be existed only in parts of magnet because many of them drew magnetic field line of a specific areas around magnets. Students had misconceptions that magnetic forces exist only on the poles not in the middle around a horseshoe magnet. Also the disc-shape magnet made students to reveal various types of misconceptions: N- and S-poles are mixed in a whole magnet and right part of a disc-shape magnet is N-pole, left part is S-pole. Students who had not studied magnetic fields of around a magnet and electromagnets could not draw the correct patterns of iron dust suggest that it is indispensable for students to teach how patterns of iron filings would represent a visual image of magnetic fields in order to understand magnetic fields.