• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.4 s.235
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• pp.495-503
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• 2005

Experiments were conducted in a low speed stationary annular cascade to investigate local heat transfer characteristics on the tip and shroud and the effect of inlet Reynolds number on the tip and shroud heat transfer. Detailed mass transfer coefficients on the blade tip and the shroud were obtained using a naphthalene sublimation technique. The turbine test section has a single stage composed of sixteen guide vanes and blades. The chord length and the height of the tested blade are 150 mm and about 125 mm, respectively. The blade has flat tip geometry and the mean tip clearance is about $2.5{\%}$of the blade chord. The inlet flow Reynolds number based on chord length and incoming flow velocity is changed from $1.0{\times}10^{5}\;to\;2.3{\times}10^{5}.$ to investigate the effect of Reynolds number. Flow reattachment after the recirculation near the pressure side edge dominates the heat transfer on the tip surface. Shroud surface has very intricate heat/mass transfer distributions due to complex flow patterns such as acceleration, relaminarization, transition to turbulent flow and tip leakage vortex. Heat/mass transfer coefficient on the blade tip is about 1.7 times as high as that on the shroud or blade surface. Overall averaged heat/mass transfer coefficients on the tip and shroud are proportional to $Re_{c}^{0.65}\;and\;Re_{c}^{0.71},$ respectively.

• The Research Journal of the Costume Culture
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• v.8 no.6
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• pp.887-898
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• 2000

Mourning & funeral ritual means a various kinds of ritual procedures which begins at the time of death, buried and created a graveyard, a manner of wearing funeral garment being mourning the death, finally go back to everyday life. Our mourning & funeral custom was burial at first time. After going through the era of the Three kingdoms, The unified Shilla and Korea dynasty, cremation method has been prevailed. However, based on Chu-tzu celebration in Chosun dynasty, the burial custom has been widely spread again. Nowadays, due to effective land utilization issue, excessive cost for burial and the change of thinking for cremation, the cremation is recognized as remedy of righteous funeral system. At this point, a shroud following existing burial custom burdens considerably for quality, price, size and design of it. Accordingly, it needs anew style of shroud corresponding to cremation system. As an alternative, the shroud is required simplification and standardization ; Firstly, in size, a shroud should be larger than plain clothes and differentiated in small, medium and large. Secondly, the material of a shroud would be white cotton, which can keep from pollution during burning time. Thirdly, it unifies the item. In case of man, 바지(把特, those are trousers), 저고리(赤古里, Korean-style jacket) and Durumagi(周衣, Korean topcoat). In case of woman, 치마(赤　, those are skirt), 저고리(赤古里, Koran-style jacket) and Durumagi(周衣, Korean topcoat).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.117-122
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• 2012

A blisk with rotor shroud is usually adopted in LRE turbine to maximize its performance. However it experiences severe thermal load and resulting damage during engine stating and stop. Shroud splitting is devised to relieve thermal stress on the turbine rotor. Structural analysis confirmed the reduction of plastic strain at the blade hub and tip. However, split gap at the rotor shroud entails additional tip leakage and results performance degradation. In order to assess the effect of shroud split on the turbine performance, tests have been performed for various settings of shroud split. For the maximum number of shroud splitting, measured efficiency reduction ratio was 2.65% to the value of original shape rotor.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.4
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• pp.25-31
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• 2013

A blisk with rotor shroud is usually adopted in LRE turbine to maximize its performance. However it experiences the severe thermal load and resulting damage during engine stating and stop. Shroud splitting is devised to relieve the thermal stress on the turbine rotor. Structural analysis confirmed the reduction of plastic strain at the blade hub and tip. However, split gap at the rotor shroud entails additional tip leakage and results performance degradation. In order to assess the effect of shroud split on the turbine performance, tests have been performed for various settings of shroud split. For the maximum number of shroud splitting, measured efficiency reduction ratio was 2.65% to the value of original shape rotor.

• Journal of the Korean Society of Costume
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• v.52 no.6
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• pp.115-126
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• 2002

This study is regarding on the shroud of Jeonjoo Lee (Inpyoung clan's lady) excavated from the Andong Gwon's grave. who had passed away at 1722. Through this research, we understood the way of fetal ceremony by 18 centuries' royal family, and the costume style in those days. The style and size of shrouds were likely similar with ordinary dress. For the upper dress, Lady Andong Gwon wore a piece of undershirt (sosam), 3 layed jacket(Joggoli), an upper jacket (dangui) with patched badge as well as a gold brocade formal dress(wonsam). And for the lower dress, 2 layed underpants(dansokot) and 2 layed long skirts were worn. Especially, prototype of the waist band for shroud(gowdo) and a kind of headgear(gokdoli) was found in this study along with the headdress for woman's shroud(yomo) and the shoes for woman's shroud(chahwea). In this study, understanding the costume of upper class at 18 centuries during Chosun Dynasty.

• Journal of ILASS-Korea
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• v.9 no.3
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• pp.35-41
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• 2004

The spray characteristics were investigated to study the effect of shroud air with swirl flow on simplex type fuel injector for gas turbine combustor. The spray tests using PDA(Phase Doppler Anemometry) technique were conducted to compare the performance of simplex atomizer with $0^{\circ},\;40^{\circ},\;50^{\circ}$ swirled-shroud air conditions. In this study. we found that the injector with strong swirled-shroud air has the better atomization Performance compared with weaker swirled and non-swirled conditions.

• Journal of the Korean Society of Costume
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• v.53 no.3
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• pp.73-87
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• 2003

The custom and shroud for funeral rites of the early 17th Century based on the excavated costume from the grave of Mrs. Jung (1565 - 1614) are studied in this paper. The grave was located in the Pohang, Kyungbuk Province and was excavated in, April 1999. The remains consist of one set of epitaphs, 33 pieces of costume, 7 pieces of cloths, and 14 pieces of funeral accessaries. From these remains, this study newly reveals : 1) a specific funeral custom for the upper class from the fact that her husband, Ja-Hun Ki, was in the position of Prime Minister for the Chosun government when she died, 2) a fact that women also wore a formal dress with round-shaped collar (Dalryoung) and a concubine could use rectangular tablets ((Hyungbae) with peacock pattern according to her husband's rank, 3) a whole set of shroud used for women in the early 17th Century, and 4) specific construction methods for individual shroud.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.256-260
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• 2013

The fan-shroud plays the important role in cooling down the engine heat by the forced convection. As the fan-shroud is made by injection molding, the unbalance of the fan blades is inevitable, and its low frequency characteristics makes it easy to excite the resonances of the environmental structures. So controlling its vibration, specially the dominant vibration source of unbalance vibration, is one of key factor to improve the sound and vibration quality of the modern vehicles. This paper introduces the plane balancing method, the most appropriate way of controlling the fan-shroud by generating the acceleration orbit measured from 2 accelerometers, and proves its balancing effect by the experiment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.859-862
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• 2002

The Core Support Barrel (CSB) is a major component of Reactor Internals, and is designed to support and protect the Reactor Core. In this study, Reactor Core, Core Shroud and CSB were simplified to coaxial cylinders and then the offset of Reactor Core & Core Shroud to the dynamic characteristic of CSB was analyzed. For the beam modes, natural frequencies of the cantilevered cylinder are compared with those of the cantilevered beam. And it was found out that shear modulus must be used correctly to convert the shell model to the equivalent beam model. From the dynamic characteristics of the beam model, it was found out that natural frequencies are proportional to the length of Reactor Core & Core Shroud and inversely proportional to the mass. From the comparison with the dynamic characteristics of a beam model and a lumped-mass model it was found out that the size of lumped-mass must be determined considering both the length and the mass of Reactor Core & Core Shroud.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.5
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• pp.408-415
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• 2011

Advanced tanks in the future combat system are expected to have the trends of large caliber, high explosive shell and light weight for destructive power and improvement in mobility. Their guns are required to have longer barrels to meet increased muzzle exit velocities. However, as the length of the barrel is extended, the vibrations induced by the breech forces in fire and the terrain lead to increased muzzle pointing errors. Therefore, the fire-induced and terrain-induced vibrations must be attenuated. A method to reduce these vibrations without the significant increase of the gun mass is to use the forward thermal shroud as part of a tuned mass damper. In this study, the dynamically-tuned-shroud using this shroud and leaf springs is introduced and its effectiveness on the vibration attenuations of the barrel are verified. The parametric studies on the stiffness of these leaf springs are performed and the analytical results are verified using the experimental model of the dynamically-tuned-shroud.