• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.401-407
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• 2012

The recent manufacturing process in the thin wafers and flat panel necessitate new approaches to reduce handling fragile and surface-sensitive damage of components. This paper presents a new pneumatic levitation for non-contact handling of parts and substrates. This levitation can achieve non-contact handling by blowing air into an air pressure pick-up head with radial passages to generate a negative pressure region. Negative pressure is caused by the radial air flow by nozzle throat and through holes connecting to the bottom region. The numerical analysis deals with the levitational motion with different design factors. The dynamic motion is examined in terms of force balance(dynamic equilibrium) occurring to the flow field between two objects. The stable equilibrium position and the safe separation distance are determined by analyzing the local pressure distribution in the fluid motion. They make considerable design factors consisting the air pressure pick-up head. As a result, in case that the safe separation distance is beyond 0.7mm, the proposed pick-up head can levitate stably at the equilibrium position. Furthermore, it can provide little effect of torque, and obtain more wide picking region according to the head size.

• Journal of Korea Foundry Society
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• v.24 no.1
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• pp.26-33
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• 2004

The pressure of the mold flux acting on the meniscus shell was investigated through the coupling analysis of heat transfer in the mold and fluid flow in the flux caused by the mold oscillation. Finite element method was employed to solve the conservation equation associated with appropriate boundary conditions. As reported by previous workers, the axial pressure is positive on the negative strip time and negative on the positive strip time. A maximum pressure is predicted toward the top of the meniscus shell which has the thin shell arid a maximum value is in proportion to the relative mold oscillation velocity. The relative mold oscillation velocity was changed by the effect of meniscus level fluctuation. Therefore the pressure of the mold flux acting on the meniscus shell was different each cycle of the mold oscillation due to the irregularity of relative mold oscillation velocity.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.621-625
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• 2001

Objectives: We examined if their hematological status could be changed by blood loss in patients treated with bleeding pressure therapy. Methods: The patients were divided into two groups as follows: The Subject group(B) were 42 cases treated with bleeding pressure therapy. The Control group(N) were 43 cases treated with negative bleeding pressure therapy, We checked CBC & differ cell count of two groups. Results: The means of RBC, Hb count and Hct were slightly decreased after 1 week. but they were recovered after 2 weeks. Conclusions: These results indicate that Bleeding Pressure Therapy don't reduced RBC, Hb count and Hct in Patients.

• Advances in aircraft and spacecraft science
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• v.6 no.6
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• pp.515-528
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• 2019

The structural vibrations of a flat plate induced by fluctuating wall pressures within wall-bounded transonic jet flow downstream of a high-aspect ratio rectangular nozzle are simulated. The wall pressures are calculated using Hybrid RANS/LES CFD, where LES models the large-scale turbulence in the shear layers downstream of the nozzle. The structural vibrations are computed using modes from a finite element model and a time-domain forced response calculation methodology. At low flow speeds, the convecting turbulence in the shear layers loads the plate in a manner similar to that of turbulent boundary layer flow. However, at high nozzle pressure ratio discharge conditions the flow over the panel becomes transonic, and the shear layer turbulence scatters from shock cells just downstream of the nozzle, generating backward traveling low frequency surface pressure loads that also drive the plate. The structural mode shapes and subsonic and transonic surface pressure fields are transformed to wavenumber space to better understand the nature of the loading distributions and individual modal responses. Modes with wavenumber distributions which align well with those of the pressure field respond strongly. Negative wavenumber loading components are clearly visible in the transforms of the supersonic flow wall pressures near the nozzle, indicating backward propagating pressure fields. In those cases the modal joint acceptances include significant contributions from negative wavenumber terms.

• Korean Journal of Community Nutrition
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• v.4 no.1
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• pp.57-63
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• 1999

This study was done to investigate the blood pressure, BMI and serum lipids of cerebrovascular accident patients in Seoul. The subjects were 195 Korean urban cerebrovascular accident patients who were hospitalized at Dong Seo Oriental Hospital in Seoul from June, 1997 to December, 1997. There were more cerebral infarction patients(164) than cerebral hemorrhage patients(31). Cerebral infraction patients were prevalent for subjects in their sixties, but cerebral hemorrhage patients were most commonly in their fifties. The BMI of cerebral infarction accidents was significantly higher than that of cerebral hemorrhage patients(p<0.05). Mean diastolic blood pressure of cerebral hemorrhage patients was significantly higher than that of the cerebral infarction patients(p<0.05). The mean systolic blood pressure of the cerebral hemorrhage patients was higher than that of the cerebral infarction patients, not statistically significant. The serum total cholesterol and glucose levels of the cerebral infarction patients was significantly higher than those of the cerebral hemorrhage patients(p<0.05). Serum total cholesterol(p<0.01), triglyceride(p<0.05) and LDH(p<0.01) levels of female subjects were significantly higher than those of male subjects. Serum total cholesterol has a negative correlation with serum GOT and GPT, but has a positive correlation with triglyceride. Serum triglyceride has a negative correlation with diastolic blood pressure but has a positive compellation with serum glucose.

• Journal of Haehwa Medicine
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• v.16 no.2
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• pp.199-210
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• 2007

Objective & Methods : The case report is to observe 27 case of venesection with negative pressure therapy(buhang) operated at CV17 (Danjuong) on sudden palpitation. We carried out to analyze the distribution and Martin's evaluation and weighted scale by sex & age, patient conditional grade, accompanied symptoms, duration, number of treatments as well. Results : 1. Forties is significantly distributed on sudden palpitation. 2. Depression instance out of many accompanied symptoms is significantly distributed. 3. Mean of operant frequency is significantly resulted on 10 or 11 times. 4. The improvement on the weighted scale is over one grade. 5. Younger is high on the assessment of treatment on Martin's evaluation and weighted scale by age, while older is low. 6. Lesser one year and more three years is some significantly resulted on the assessment of treatment on Martin's evaluation and weighted scale by duration. 7. Pleurodynia, insomnia, distress in the stomach are effective more 90%, and depression, asthma are more 80% on the assessment of treatment on Martin's evaluation by accompanied symptoms, while asthma and pleurodynia are very significantly resulted on the assessment of treatment on weighted scale. 8. The assessment of treatment on Martin's evaluation and weighted scale have no connection with operant frequency. Conclusion : These results suggest that venesection with negative pressure therapy(buhang) operated at CV17 (Danjuong) has a therapeutic effect on on sudden palpitation.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.3
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• pp.37-44
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• 2023

Purpose: To decrease cross-infection, it's essential to analyze the spatial composition of the 'PPE doffing area'. Instead of solely relying on manpower standards, we should focus on responding to infectious diseases within the context of space planning. By doing so, we can lower the risk for healthcare workers' infection and ensure a level of safety in various environmental changes or new manpower input situations. Methods: This analysis is conducted specifically for facilities with negative pressure isolation wards. Additionally, interview surveys to obtain feedback from healthcare workers and incorporate their expertise into the design of the 'PPE doffing area' have been carried. Results: In a PPE doffing area, the standard spaces include a PPE doffing room, a shower room, and a clothing room. Depending on the facility environment or the level of infectious diseases, a Decontamination room or Anteroom can be optionally added. Healthcare workers who remove their PPE in the PPE doffing room should avoid re-entering the Negative pressure room. The shower room is often underutilized. When planning for a future PPE doffing area, an aisle space or passageway must be included even if a shower room is planned. Implications: This study examined the space used by healthcare workers rather than patients, with a focus on infection prevention through architectural planning rather than individual efforts. However, the investigation was limited to facilities that have been converted from general wards to negative pressure isolation wards, so it cannot be generalized to all infectious disease facilities.

• Journal of Oriental Medical Thermology
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• v.4 no.1
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• pp.15-22
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• 2005

Thermal change of thermogram can be induced by heat, drugs, diseases, stress, treatments and so on. Because they changed blood circulation of body surface. Negative treatment have been used in oriental medicine to decrease pain and to purify fluids and it can also change blood circulation of body surface. The purpose of this study was to observe the detail changes of temperature after negative treatment and to know the differences according to the negative pressures by thermography. This study was carried for 5 days and thermogram was operated 15 times. The patient had been treated on the back with electromotive type negative treatment and the treated sites was devides into 4 parts with different negative pressure. The results was that the temperature of all parts rised after treatment and the highest point was 10 minutes after treatment. The differences according to the negative pressures was that the temperature of the 55mmHg part rised particularly than the others and it continued until 40 minutes after treatment. There were no differences between 30mmHg and 40mmHg part. The temperature of 50mmHg part were low than the others during all thermogram.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.3
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• pp.235-242
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• 2014

To investigate pressure distributions on the shaft surface of the air bearing, the commercial CFD software was employed to study three different nozzle geometries to improve the nozzle performance: general drill-shaped, matched cube-shaped and trimmed exit nozzles. Under the influence of stagnation point, the maximum pressure was observed at the center of shaft surface for all cases. Owing to the blocking effect of a fine gap between the shaft surface and the nozzle exit, the drill-shaped nozzle has the rapid local pressure increase near the nozzle exit corner, generating the ring vortex in the radial direction within pressure ratio of 6.92, and its pressure becomes negative in a certain range of downstream. In comparison, the contoured nozzle showed a local pressure increase in the measured range of pressure ratios, but a negative pressure appeared within the pressure ratio of about 10. The trimmed nozzle was seemed to extend the high pressure zone near the stagnation point in the radial direction substantially, and no negative pressure was appeared in the whole range. Based on these observations, it is found that trimming nozzle exit becomes more effective for improving the performance than modifying the nozzle inside contour.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.1
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• pp.92-99
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• 1994

Diamond thin film was deposited on n type (100) Si substrate by MPECVD(Microwave plasma Enhanced Chemical Vapor Deposition). For the increase in nucleation density of diamond, Si substrate was pretreated by diamond powder or negative bias voltage was applied to the substrate during the initial deposition. In the case of retreated Si substrate, the diamond thin film quality was enhanced with increasing the total pressure in the range of 20~150 Torr. For the negative bias voltage, the formation condition of the diamond was seriously affected by $CH_4$ concentration and total pressure. The formation condition will be discussed with electrical current of substrate generated by plasma ions which depend on $CH_4$concentration, bias voltage, and total pressure.