• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.6
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• pp.479-487
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• 2015

In a reflected shock tunnel, stagnation conditions of a nozzle are determined by the flow behind a reflected shock. When calculating the flow behind the reflected shock, unlike a shock tube, the flow leakage through the nozzle is to be considered. The analytical studies were done to find out the characteristics of the stagnation conditions of the nozzle with various nozzle throat size. Experiments and numerical simulations were also carried out for further understanding of the flow leakage effects. It was found that the nozzle stagnation pressure was diminished by the increase of the size of the nozzle throat. It was also found that the steady pressure in the stagnation were maintained well at the area ratio of the driven tube to the nozzle throat is 4.5.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.11
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• pp.754-761
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• 2011

The present study numerically investigates two-dimensional flow and heat transfer in the multiple confined impinging slot jet. Numerical simulations are performed for the different Reynolds numbers(Re=100 and 200) in the range of nozzles from 1 to 9 and height ratios(H/D) from 2 to 5, where H/D is the ratio of the channel height to the slot width. The vector plots of velocity profile, stagnation and averaged Nusselt number distributions are presented in this paper. The dependency of thermal fields on the Reynolds number, nozzle number and height ratio can be clarified by observing the Nusselt number as heat transfer characteristic at the stagnation point and impingement surface. The Nusselt number at the stagnation point of the central slot shows unsteadiness at H/D=3 and Re=200. The value of Nusselt number at the stagnation point of the central slot decreases with higher Reynolds number and number of nozzle although overall area averaged Nusselt number increases. Hence careful selection of geometrical parameters and number of nozzle are necessary for optimization of the heat transfer performance of multiple slot impinging jet.

• Journal of Haehwa Medicine
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• v.8 no.1
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• pp.371-378
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• 1999

Through the thought of etiology and pathogenesis of convulsion disease in past document, we concluded as follow. 1. Convusion disease brings about some symptoms such as myotonia, neck stiffness, myospasm of four limbs, and in the ancient times it was called in Gye-Jong, Chu-Pung(抽風), Chi. 2. Etiologies of convulsion disease are external invasion of Pung-Han-Seub(風寒濕) and Ybul-Sa(熱邪), mistreatment, great loss of blood, deficiency of Gi-Hyul(氣血), stagnation of phlegm and blood. 3. There are four pathologic cases which arise convulsion disease. They are muscular denutrition from meridian stagnation by external invasion, muscular denutrition of heat injury, stagnation of phlegm and thrombus in meridian, muscular denutrition with deficiency of Gi-Hyul(氣血). 4. The treatment methods of convulsion disease are divided into three. If caused by external invasion, the methods are San-Han-Hae-Gi(散寒解肌), Hwa-Yung-Jo-Joong(和營調中). If caused by deficiency of Gi-Hyul(氣血), the method is Bo-Gi-Ik-Hyul(補氣益血). If caused by stagnation of phlegm and blood, the methods are Hwal-Hyul-So-Eo(活血消瘀), Do-Dam-Gun-Bi(導痰健脾).

• Journal of Haehwa Medicine
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• v.18 no.1
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• pp.49-66
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• 2009

1. Hiccup is usually named as Hae yek, Hyel yek, Yel yek. 2. The cause of hiccup are stomach cold, rising of stomach fire, stagnation of vital energy and stagnationof phlegm, yang deficiency of spleen and kideny, deficiency of stomach-yin, or mental disorder due to the stagnation of phlegm, dyspepsia, depressed vital energy. 3. Vicera and Bowels related with Hiccup are lung, spleen, stomach, and heart. 4. The treatment of hiccup are dispel cold by warming the middle warmer due to stomach cold, expel the heat-evil to loose hollow-organ due to rising up of stomach yin, regulate vital energy and dissipate phlegm due to stagnation of vital energy and stagnation of phlegm, warm and recuperate both of spleen and kidney due to spleen and kidney yang deficiency, nourish the stomach to promote the production of body fluid due to deficiency of stomach yin. 5. Regarding neuropsychiatric aspect of hiccup, qi movement disorder was the main mechanism of disease and qi depression was the main cause. The prescriptions for neuropsychiatric hiccup were Mokhwangjogisan Pyunjakjunghyangsan, Daegwakhyangsan, and Haeaedan.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.3
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• pp.11-19
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• 2015

Objective : This study aimed to develop and preliminary validate the Mibyeong Questionnaire (MQ) based on Deficiency-Stagnation pattern, which was report of a person's health condition that comes directly from the person. Method : The first phage of developing a MQ was to generate and exhaustive list of all MQ issue that are relevant to the domain of interest, using literature research and expert group discussions. Through those steps, we established MQ with 33 items divided into two parts: 21-item deficiency pattern and 12-item stagnation pattern. The second phage, we examined the preliminary tests of reliability and validity including the 16-item Deficiency of MQ (16D-MQ), with data (n=1,890) already collected on the Korean medicine data center in KIOM. Results : Exploratory factor analysis revealed three factors of the 16D-MQ. These factors were fatigue(Qi, 氣); psychic and physical elements(Shen, 神); and skin and hair(Jing, 精). Cronbach's coefficient alpha was 0.876 and the intraclass correlation coefficients was 0.368-0.538. In support of criteria validity, the 16D-MQ was weakly correlated with EQ-5D and physicians's opinion, but it was acceptable. Conclusion : The MQ shows that it has an appropriate level of internal consistency and validity. We think further study to reveal its reliability and validity, including stagnation pattern as well as deficiency pattern, is needed.

• Journal of Korea Water Resources Association
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• v.37 no.8
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• pp.623-630
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• 2004

In this paper, the hydraulic model tests are conducted for the hydraulic characteristics at channel junctions. The experiments are examined through the variation of approaching angle, discharge in the upstream main channel and the discharge ratio between the main channel and the tributary. The experiments are conducted in the channel model having the length of 450cm, the widths of 40cm and 32cm. Four water tanks and pumps are installed in the experimental channel. The length of stagnation zone is increased by Increasing of approaching angle and the discharge in the upstream channel. The length of stagnation increase with the discharge ratio between the main channel and the tributary. However, the variation of the stagnation zone near the channel junctions is little at the same approaching angles and the discharge ratioes between the main channel and tributary. However, the variation of the stagnation zone near the channel junctions is little at the same approaching angles and the discharge ratioes between the main channel and tributary. Accelerating zone of the velocity is occurred in the middle of the channel in the small approaching angle. However, the influence zone of the accelerating velocity is increased by increasing the approaching angle.

• International Journal of Fluid Machinery and Systems
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• v.9 no.4
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• pp.338-353
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• 2016

Information on the surge behaviors and stall stagnation boundaries for a nine-stage axial flow compressor are summarized on the basis of analytical data in comparison with those for a single-stage one, with attention to the pressure ratio effect. The general trends of the surge loop behaviors of the pressure-mass flow are similar for both compressors including the fact that the subharmonic surges tend to appear very near the stall stagnation boundaries. With respect to the nine-stage compressor, however, the mild loops in the subharmonic surges tend to be very small in size relative to the deep loops, and at the same time, insufficient surge recovery phenomenon, which is a kind of subharmonic surge, appears also far from the stagnation boundary for relatively short delivery flow-paths. The latter is found to be a rear-stage surge caused by unstalling and re-stalling of the rear stages with the front-stages kept in stall in the stalled condition of the whole compressor, which situation is caused by stage-wise mismatching in the bottom pressure levels of the in-stall multi-stage compressor. The fundamental information on the stall stagnation boundaries is given by a group of normalized geometrical parameters including relative delivery flow-path length, relative suction flow-path length, and sectional area-pressure ratio, and by another group of normalized frequency parameters including relative surge frequencies, modified reduced resonance frequencies, and modified reduced surge frequencies. Respective groups of the normalized parameters show very similar tendency of behaviors for the nine-stage compressor and the single-stage compressor. The modified reduced resonance frequency could be the more reasonable parameter suggesting the flow-induced oscillation nature of the surge phenomena. It could give the stall stagnation boundary in a more unified manner than the Greitzer's B parameter.

• Journal of Society of Preventive Korean Medicine
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• v.26 no.3
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• pp.87-96
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• 2022

Objective : We examined the literature of <Life Nurturing Method and Conduction Exercise(養生方導引法)> of 《Pathogenesis and Manifestations of Food Stagnation and Indigestion(宿食不消病諸候)》 in 『Treatise on the Pathogenesis and Manifestations of All Diseases(諸病源候論)』 and actually implement its movement to present conduction exercise based on the principle of Korean medicine treatment. Method : We used web services for traditional Eastern Asian medical classics and some literature on 『Treatise on the Pathogenesis and Manifestations of All Diseases(諸病源候論)』 and its <Life Nurturing Method and Conduction Exercise(養生方導引法)〉. The original text was interpreted and the movements of <Life Nurturing Method and Conduction Exercise> were implemented according to the literature. A qi-gong(氣功) expert demonstrated the movements and we took pictures. Results : <Life Nurturing Method and Conduction Exercise(養生方導引法)> was written in the symptom of Food Stagnation and Indigestion(宿食不消候) and the symptom of food damage and excessive eating(食傷飽候) among the chapters of 《Pathogenesis and Manifestations of Food Stagnation and Indigestion(宿食不消病諸候)》. With respect to the movements and breathing, stretching your back allows qi(氣) energy to enter the lower cinnabar field(下丹田) immediately, and when the lower stomach is full of qi it can be transported upper body, leading to better communication of qi around the body. Conclusion : The practical implementation of the movements and postures will contribute to understanding the characteristics, pathology, and contents of diseases related to indigestion, and furthermore it can be widely used clinically for prevention and treatment of digestive disorders.

• Transactions of the Korean Society of Mechanical Engineers
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• v.6 no.4
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• pp.301-307
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• 1982

The purpose of this investigation is to study heat transfer characteristics at a stagnation point on a flat plate caused by upward impinging water jet. At the stagnation point, heat transfer results by impinging water jet are being compared with the ones with supplementary water. Optimum supplementary water quantity are supplied in order to improve the effect of heat transfer for each nozzle-to-plate distance. As the nozzle outlet velocity increases, the heat transfer coefficient at stagnation point consequently increases. Changing the nozzle-to-plate distance, growth rate of heat transfer also varies accordingly. This optimum range of Reynolds number is obtained to improve heat transfer effect.

• Journal of computational fluids engineering
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• v.7 no.3
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• pp.1-8
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• 2002

The counter jet flow which is injected against the free stream at stagnation region of blunt body for improvement of aerodynamic performance has been studied by using upwind Navier-Stokes method. The variations of drag force and upwind forward penetration depth due to changes in the stagnation thermodynamic properties of counter jet flow such as total pressure, Mach number, and total temperature have been studied. The results show that the changes in the stagnation pressure and Mach number have large effects on the wall pressure and drag force, but the total temperature does not affect the wall pressure and drag force.