• Journal of Advanced Marine Engineering and Technology
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• v.24 no.2
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• pp.17-23
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• 2000

Experimental investigations were conducted to study the forced convection of fully-developed turbulent flow in horizontal equilateral duct fabricated with the same length and equivalent diameter, but different surface roughness pitch ratio(P/e) of 4, 8 and 16 on the one side wall only. The experiments were performed with the hydraulic diameter based Reynolds number ranged from 70,000 to 10,000. The entire bottom wall of the duct was heated uniformly and the other surfaces were thermally insulated. To understand the mechanisms of the heat transfer enhancement, measurements of the heat transfer were done to investigate the contributive factor of heat transfer promotion, namely, the fin effect. And the results were compared with those of previous investigations for similarly configured channels, at which they were roughened by regularly spaced transverse ribs in the rectangular and circular channels.

• Journal of computational fluids engineering
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• v.3 no.2
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• pp.27-38
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• 1998

Rotating flow of a stratified fluid contained in a circular cylinder with unstable temperature gradient imposed on the side wall of it has been numerically studied. The temperatures at the endwall disks are constant. The top disk of the container is coider than that of the bottob disk, as much as the temperature difference n${\Delta}$T, (0${\leq}$n${\leq}$3). Flows in the vessel are driven by an impulsive rotation of the hot bottom disk with respect to the central axis of the cylinder. Flow details have been acquired. For this flow, the principal balance in the interior core is characterized by a relationship between the radial temperature gradient and the vertical shear in the azimuthal velocity. As the buoyancy effect becomes appreciable, larger portions of the meridional fluid transport are long-circuit from the bottom disk to the interior region via the side wall.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.65-70
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• 2000

Experimental investigations were conducted to study the forced convection of fully-developed turbulent f)on· in horizontal equilateral duct fabricated with the same length and equivalent diameter, but different surface roughness Pitch ratio(P/e) of 4, 8 and 16 on the one side wall only The experiments were performed with the hydraulic diameter based Reynolds number ranged from 70.000 to 10,000 The entire bottom wall of the duct was heated uniformly and the other surfaces were thermally insulated. To understand the mechanisms of the heat transfer enhancement. measurements of the heat transfer were done to investigate the contributive factor of heat transfer promotion. namely the fin effect. And the results were compared with those of Previous investigations for similarly configured channels, at which they were roughened by regularly spaced transverse ribs in the rectangular and circular channels.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.590-593
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• 2009

To identify the detailed 3D flow characteristics of a model scramjet engine, a unified 3D numerical analysis was performed. The numerical domain of concern includes the entire flow path of the model scramjet engine extending from the intake to the nozzle exhaust. Turbulent models($k-{\omega}$ SST and low Reynolds number k-e with Sarkar model) were applied with comparison of experiment result. Intake side wall's effect on flow characteristics was analyzed in view points of flow quality at inlet duct and near the flame holder as well. The code is paralleled with multi-block feature using MPI(Massage Passing Interface) library to speed up the 3D calculation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.166-167
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• 2015

Because of energy crisis at all around the world, there is many method and system which for improving energy efficiency has appeared in construction industry. And then, 20% of entire building energy loss is emissed to exterior of buildings, that is important to building's entire energy efficiency. So, many research has been conducted for imporve exterior energy efficiency and generally it called insulation of wall. Method for wall insulation can be classified interior system and exterior system which defined installation place of insulation board whether interior or exterior of structural wall. However, interior system has thermal problem such as thermal-bridge which can be necessarily occur condensation. and exterior system has constructional problem such as difficult to construction because exterior and finish work so expensive construction cost than other insulation method. Thus, sandwich insulation wall system has been appeared for solving these problems. Sandwich insulation system must using wall connecting things because both side walls is divided by center insulation. At this, Through the heat at wall connecter, it can be occured thermal-bridge and broken insulation board when under construction will be bring negative effect by reducing wall thickness and insulation deficit. At this study, we were compared previous sandwich insulation system and analysis these system's problem for develop the improving constructability and performance of sandwich insulation system.

• The Journal of Korean Medicine
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• v.16 no.1 s.29
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• pp.71-95
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• 1995

To be helpful to the treatment of pulmonary cancer with oriental medicine, we got clinical reports together and analyzed the data. The results were obtained as follows: 1. The treating methods could be summarized as three methods that were reinforcing vital energy, eliminating harmful Qi, and reinforcing vital energy with eliminating harmful Qi. The methods of reinforcing vital energy were supplementing Qi & Yin, increasing pahological heat & reinforcing kidney, augmenting Qi & blood, supplementing vital energy and strengthening fundermental energy, reinforcing spleen and increasing Qi, lubricate Yin and lung, and the other methods of eliminating harmful Qi were transforming pathological fluid and softening, clarifying heat and eliminating poison, dipersing lung and softening, toxicding and softening, guiding Qi and activating blood, clarifying heat and dispersing lung, guiding Qi and counteracting stress etc., and the methods of supplementing vital energy with eliminating poison were reinforcing spleen and transforming pathological fluid, increasing Qi and activating blood, supplementing Yin and clarifying heat, reinforcing spleen and dry the dampness, lubricating lung and transforming patholigical fluid and supplementing Qi and activating blood. 2. The oriental prescriptions used for pulmonary cancer were Chunkeum-Weekyungtang & Sohamhwingtang, Jinhayookgunjatang, Hyulboochukeotang, Bokbangkyogonamtang was reported to be effective in the treatment of metastasis. 3. Bokbangshinjingtang and haewool were applied for the complications of pulmonary cancer, Soshihotang for fever, hangamryung for tumor pain. Prunus ansu Komarov, Eriobotrya japonica Lirdley, Pyrrosiae lingua Farwel, Steomon japonica Miguel, Maximowiczia chinensis Ruprecht var, Morus bombycis Koidzumi for cough, Panax Pseudo-ginseng Wall. var, Bletilla striata Reichenbach f., Acacia catechu(兒茶) for hemoptysis, Lonicerae flos, Aspongopus chinensis(九香蟲) for chest pain, Cypsum Fibrosum, Gazella gutturosa, Scutellaria baicalensis Georgi, Gypsophila oldhamiana Miquel for fever, Lepidii semen descurainiae semen, Belamcanda chinensis D.C, Gnaphalium affine(佛耳草) for asthma. 4. For the reduction of side effect by chemotherapy and radiotherapy it was known that supplementing Qi was used chiefly for side effect of chemotherapy and augmenting Yin applied to side effect of radiotherapy. 5. The oriental presciptions were suggested for the side effect by chemotherapy and radiotherapy ; Sammaekaek(參麥液), Whaebokwontang(化瘀復元湯), Hwangjungomitang(黃精五味湯), Yukmijihwangtang(六味地黃湯), Hyangsayukgunjatang(香砂六君子湯), Samlyeekulsan for side effect by chemotherapy while Geumgweisingiwhan, Hwanglyentang(黃連湯), Hwanglyenhaedoktang(黃連解毒湯), Yangyeunchungpeitang(養陰淸肺湯), Idongtang(二冬湯), Jayeunkanghwatang(滋陰降火湯) for side effect by radiotherapy.

• The Journal of the Acoustical Society of Korea
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• v.16 no.1
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• pp.76-80
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• 1997

Acoustic resonance characteristics were analyzed and their effect on the refrigerating capability were experimentally verified on a fabricated Hofler-type thermoacoustic refrigerating system. Factors governing the overall resonance are the resonator composed of a cavity and two pipes, the loudspeaker driving the resonator, and rear side impedance characteristics of speaker housing. All these are coupled with electric constants of the speaker to exhibit electric resonance. Also the 'wall-effect' within the resonator causes attenuation to reduce the sharpness of the resonance. Analysis and experiments showed housing and the wall-effect of the resonator reduce the sharpness of resonance. Maintaining the accuracy of the resonance is, therefore, very important for efficient refrigeration.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.14-21
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• 2001

An experimental study has been conducted to investigate the heat/mass transfer characteristics within a square film cooling hole with asymmetric inlet flow conditions. The asymmetric inlet flow condition is achieved by making distances between side walls of secondary flow duct and film cooling hole different; one side wall is $2D_h$ apart from the center of film cooling hole, while the other side wall is $1.5D_h$ apart from the center of film cooling hole. The heat/mass transfer experiments for this study have been performed using a naphthalene sublimation method and the flow field has been analyzed by numerical calculation using a commercial code. Swirl flow is generated at the inlet region and the heat/mass transfer pattern with the asymmetric inlet flow condition is changed significantly from that with the symmetric condition. At the exit region, the effect of mainstream on the inside hole flow is reduced with asymmetric condition. The average heat/mass transfer coefficient is higher than that with the symmetric condition due to the swirl flow generated by the asymmetric inlet condition.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.7
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• pp.937-944
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• 2002

An experimental study has been conducted to investigate the heat/mass transfer characteristics within a square film cooling hole with asymmetric inlet now condition. The asymmetric inlet now condition is achieved by making distances between side walls of the secondary now duct and the film cooling hole different; one side wall is $2D_h$ apart from the center of the film cooling hole, while the other side wall is $1.5D_h$ apart from the center of the film cooling hole. The heat/mass transfer experiments for this study have been performed using a naphthalene sublimation method and the now field has been analyzed by numerical calculation using a commercial code. Swirl now is generated at the inlet region and the heat/mass transfer pattem with the asymmetric inlet now condition is changed significantly from that with the symmetric condition. In the exit region, the effect of mainstream on the inside hole now is reduced with the asymmetric condition. The average heat/mass transfer coefficient is higher than that with the symmetric condition due to the swirl now generated by the asymmetric inlet condition.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.5
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• pp.3-11
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• 2011

In this study, the effect of treating 1-dimensional diffusers on the classroom acoustics was investigated to determine if the diffuser are beneficial for performing the preferred acoustical conditions for speech. A 1/10 scale model of a classroom was used to measure the acoustical parameters, T30, $C_{50}$, STI and SNR in that room. The room acoustical conditions were varied by treating diffusers either on the front or side walls of the classroom. When the diffusers were treated on the side walls around the student's areas, a shorter reverberation time at low frequencies was obtained and resulted in performing uniform reverberation times across the frequency bands. The $C_{50}$ values at mid- and high-frequencies were increased by treating the diffusers either on front or side wall surfaces. The highest STI and SNR values were obtained when the diffuser was treated on the front wall around the teacher's areas. It is found that diffusers are beneficial to increase the intelligibility of speech for the rear seats of the rooms.