• Journal of the Korean Society for Aviation and Aeronautics
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• v.11 no.1
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• pp.41-55
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• 2003

A calibration jet system using separate blower is developed to calibrate a flow sensor effectively. Designed open circuit type mini calibration jet system, which has the dimension of $0.5m(W){\times}1.17m(H)$ is small compared with conventional calibration jet systems. The exit of nozzle has exchangeable contractions with a cross section area of $38.5cm^2$ , and a cross section area of $113.1cm^2$, respectively. The ranges of wind speed at exit of exchangeable nozzles are $7.5{\sim}42\;m/s$ and $1.8{\sim}16.5\;m/s$, respectively. The input power for the high pressure blower is 1.18kW. The turning vanes for corner was rolled flat plate parallel to the flow direction. The flow conditioning screen was located immediately downstream of the wide-angle diffuser. The honeycomb and two flow conditioning screens were located in the stagnation chamber. From the economical point of view and the simplicity of the calibration jet system set up and handling, it can be said that the developed calibration jet system is an effective calibration jet system. This system can also be used to calibrate the flow sensor with high resolution.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.4
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• pp.86-100
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• 1998

The impingement of the fuel spray on the wall within the combustion chamber in compact high-pressure injection engines and on the intake port wall in port-fuel-inje- ction type engines is unavoidable. It is important to understand the characteristics of impinging spray because it influences on the rate of fuel evaporation and droplet distrib- ution etc. In this study, the numerical study for the characteristics of spray/wall interaction is performed to test the applicability and reliability of spray/wall impingement models. The impingement models used are stick model, reflect model, jet model and Watkins and Park's model. The head of wall-jet eminating radilly outward from the spray impingement site contains a vortex. Small droplets are deflected away from the wall by the stagnation flow field and the gas wall-jet flow. While the larger droplets with correspondingly higher momentum are impinged on the wall surface and them are moved along the wall and are rolled up by wall-jet vortex. Using the Watkins and Park's model the predicted results show the most reasonable trend. The rate of increase of spread and the height of the developing wall-spray is predicted to decrease with increased ambient pressure(gas density).

• Korean Journal of Animal Reproduction
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• v.10 no.1
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• pp.66-70
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• 1986

The findings of a study on reproductive disorders and their causes with 685 dairty cows raised on dairy farms located in Cheju city, Jochun, Hallim and Sung-up are summarized as follows; 1. Among a total 685 dairy cows, 149 heads were identified as having reproductive disorders. They were subdivided into 26 genital organ diseases (3.8%), 53 delivery abnormalities (7.7%), 17 stagnation of after-birth (2.5%), 23 long period nonestrus (3.4%) and 30 repeat breeders (4.4%). Also, the regional incidence of those disorders was recorded as high as 30.8-31.5% in Jochun and Cheju city, and as low as 12.6-16.6% in Sung-up and Hallim districts. 2. The regional incidence of delivery abnormalities was estimated as high as 10.7% in the Cheju city area, and gradually reduced to 8.8% in Jochun, 6.8% in Sung-up and 6.2% in the Hallim district. Abortion (3.1%), stillbirth (2.0%) and 욘새챰 (2.6%) were included in the delivery abnormalities.

• International Journal of Fluid Machinery and Systems
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• v.8 no.1
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• pp.1-12
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• 2015

In cardiopulmonary support systems with a membrane oxygenation such as a percutaneous cardiopulmonary support (PCPS) or an extracorporeal membrane oxygenation (ECMO), blood pumps need to generate the pressure rise of approximately 200mmHg or higher, due to the high hydraulic resistances of the membrane oxygenation and of the cannula tubing. In order to realize the blood pump with higher pressure rise, higher anti-hemolysis and thrombosis performances, the development of novel centrifugal blood pump composed of two-stage has been conducted by the authors. In the present paper, effective attempts to decrease the wall shear stress and to suppress the stagnation are introduced for the prevention of hemolysis and thrombosis in blood pumps. The hemolysis test was also carried out and it was clarified that the decrease of wall shear stress is effective as a guideline of design of blood pumps for improving the anti-hemolysis performance.

• Nuclear Engineering and Technology
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• v.45 no.5
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• pp.581-588
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• 2013

This paper deals with the Safety Analysis for $CANDU^{(R)}$ 6 nuclear reactors as affected by main Heat Transport System (HTS) aging. Operational and aging related changes of the HTS throughout its lifetime may lead to restrictions in certain safety system settings and hence some restriction in performance under certain conditions. A step in confirming safe reactor operation is the tracking of relevant data and their corresponding interpretation by the use of appropriate thermal-hydraulic analytic models. Safety analyses ranging from the assessment of safety limits associated with the prevention of intermittent fuel sheath dryout for a slow Loss of Regulation (LOR) analysis and fission gas release after a fuel failure are summarized. Specifically for fission gas release, the thermal-hydraulic analysis for a fresh core and an 11 Effective Full Power Years (EFPY) aged core was summarized, leading to the most severe stagnation break sizes for the inlet feeder break and the channel failure time. Associated coolant conditions provide the input data for fuel analyses. Based on the thermal-hydraulic data, the fission product inventory under normal operating conditions may be calculated for both fresh and aged cores, and the fission gas release may be evaluated during the transient. This analysis plays a major role in determining possible radiation doses to the public after postulated accidents have occurred.

• Journal of Sasang Constitutional Medicine
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• v.27 no.4
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• pp.379-387
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• 2015

Objectives The purpose of this study was to investigate the relevance of Sasang constitution, Qi Blood pattern identification, and tongue diagnosis in subjects complaining of fatigue.Methods Seventy-three subjects who complained of fatigue were assessed using the Chalder Fatigue Scale, tongue diagnosis, pattern identification questionnaire and Sasang constitution diagnosis. The association of tongue diagnosis with Qi Blood pattern identification and Sasang constitution was evaluated.Results 1. There was no significant association between tongue diagnosis and Sasang constitution.2. Tongue color, which is one of the diagnostic indicators in tongue diagnosis, was redder in the Qi stagnation group than in the Qi deficiency and Blood deficiency groups.Conclusions Tongue diagnosis can be utilized in future if proper research regarding Sasang constitution and Sasang constitution pattern identification is conducted.

• The Journal of Korean Obstetrics and Gynecology
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• v.15 no.4
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• pp.238-246
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• 2002

Recently we observed and treated a 49-year-old postmenopausal female with enlarged uterine myoma who taking through the hormone replacement therapy(H.R.T). We regard the cause of this case as insufficiency of kidney-yin(腎陰虛), stagnation or the phlegm and pathologic blood(痰瘀阻滯) and H.R.T. ln general cases, myomas grow in size if estrogen and progesterone is present and do not increase in size if estrogen and progesterone levels are low. So if a woman can get to menopause without having symptoms from the myomas, then it is likely that she will never have problems from the growths that require treatment. But Taking postmenopausal estrogen and progestin replacement therapy can cause myomas to grow. So we recommended her to stop the H.R.T. gave herbal-medicine and acupuncture therapy. Thus we could get a good result as follows. The uterine myomas were significantly declined but no change on it's characters. Hot flush and general conditions were also significantly improved And body weight was lessened for about 4.7kg. But vaginal dryness was appeared, So we planed another therapy for that symptom.

• The Journal of Korean Obstetrics and Gynecology
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• v.15 no.4
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• pp.208-217
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• 2002

We had treated one melasma patient occurred by pregnancy with oriental medicine's method and got a good result. Melasma is often occured in pregnancy and dysmenorrhea. Most common pathology of melasma in oriental medicine is Yin deficiency with Fire and Blood Stasis. The Fire and Blood Stasis are made by Qi stagnation which is occurred by depression and stress. So we used the methods of promoting Qi and Blood, increasing Yin with clearing heat, and the result is very successful. We found out that Oriental Gynecologic therapy is most appropriate for treating woman's melasma, and could provide the treatment model.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1300-1310
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• 1990

Naphthalene sublimation technique is employed to investigate the mass transfer processes from a square cylinder at various Reynolds numbers and various angles of attack. Distribution of the local mass transfer coefficients on each face of the cylinder changes dramatically with the angle of attack. Such variation of local mass transfer rates closely connected with the complex flow phenomena such as stagnation, acceleration, separation, reattachment and vortex shedding. The average Sherwood number has a minimum value at 12.deg.-13.deg., and a maximum value at a=20.deg.-25.deg. A comparison of present mass transfer measurement with other heat transfer measurements, using the heat/mass transfer analogy, shows good agreement in average transfer rates, same trend but notable differences in local values. Therefore, naphthalene sublimation technique can be adopted to explore heat transfer processes in the complex flow situations, which is considered to be hardly possible with the conventional heat transfer measurements.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.12 s.255
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• pp.1236-1242
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• 2006

The local heat flux of spray cooling in the film boiling region were experimentally investigated for the spray region of $D_{max}$ = $0.005{\sim}0.03m^3/(m^2s)$. A twin-fluid full cone spray nozzle was employed for the experiment and the distributions of droplet flow rates were obtained for air-water full cone sprays. A stainless steel block was cooled down from initial temperature of about $800^{\circ}C$ by full cone spray. In the region near the stagnation point, it was found that the experimental data are in good agreement with the results predicted from the correlations between the local heat transfer and the local droplet flow rate proposed in the previous report. However, it was found that the experimental data of $D_r$ > $0.01m^3/(m^2s)$ are a little smaller than the results predicted from the correlations.