• 한국수학교육학회지시리즈B:순수및응용수학
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• 제13권1호
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• pp.1-10
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• 2006

The unsteady Hartmann flow of an electrically conducting, viscous, incompressible fluid bounded by two parallel non-conducting porous plates is studied with heat transfer. An external uniform magnetic field and a uniform suction and injection are applied perpendicular to the plates while the fluid motion is subjected to a constant pressure gradient. The two plates are kept at different but constant temperatures while the Joule and viscous dissipations are included in the energy equation. The effect of the magnetic field and the uniform suction and injection on both the velocity and temperature distributions is examined.

• 한국광학회:학술대회논문집
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• 한국광학회 1999년도 제16회 광학 및 양자전자 학술발표회Proceedings of 16th Optics and Quantum Electronics Conference, 1999
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• pp.218-219
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• 1999

• Journal of Radiation Protection and Research
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• 제38권3호
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• pp.157-165
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• 2013

To determine the factors affecting the external radiation dose rates of patients undergoing PET-MRI examinations and to assess the trends of these differences, we measured the changes in the dose rates of $^{18}F$-FDG during a set period of time for each body region. Consistent with theoretical predictions, the dose rate decreased over time in patients undergoing PET-MRI examinations. Furthermore, immediately after the $^{18}F$-FDG injection, the dose rate in the chest region was the highest, followed by the abdominal region, the head region, and the foot region. The dose rate decreased drastically as time passed, by 2.47-fold, from $339.23{\pm}74.70mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection to $102.71{\pm}26.17mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. In the foot region, there were no significant changes over time, from $32.05{\pm}20.23mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection, to $23.89{\pm}9.14mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. The dose rate is dependent on the individual characteristics of the patient, and differed depending on the body region and time point. However, the dose rates were higher in patients who had a lower body weight, shorter stature, fewer urinations, lower fluid intake, and history of diabetes mellitus. To decrease radiation exposure, it is difficult or impossible to change factors inherent to the patient, such as sex, age, height, body weight, obesity, and history of diabetes mellitus. However, factors which can be changed, such as the $^{18}F$-FDG dose, fasting time, fluid intake, number of urinations, and contrast agent dose can be controlled to minimize the external radiation exposure of the patient.

• 한국세라믹학회지
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• 제43권12호
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• pp.829-832
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• 2006

In this study, the influence of the magnetic field on ferrite slurry's injection time during the slurry forming process was investigated. The evaluation system of the slurry's injection time under the strong magnetic field was designed with FEM and manufactured. Studied parameters were the applied magnetic field, the input pressure of the slurry, and the supplying tube materials. As the results, the injection time was increased with the external magnetic field strength and rapidly decreased with increasing the input pressure of the slurry. Also the injection time was decreased when the supplying tube was manufactured with the magnetic material having the higher magnetic permeability than the ferrite.

• Archives of Plastic Surgery
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• 제47권1호
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• pp.54-61
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• 2020

Background Conventional methods of external bleeding for congested fingertip replants exhibit notable problems, including uncontrollable bleeding and unpredictable survival of the replant. We have added a local injection of heparin calcium to the routine use of systemic heparinization for inducing external bleeding. We retrospectively examined patients who underwent external bleeding using our method. Methods Local subcutaneous injections of heparin calcium were made in 15 congested replants in addition to systemic heparinization. Each injection ranged from 500 to 5,000 U. The average duration of the injections was 4.1 days. Surgical outcomes were analyzed and compared with a control group of patients who underwent external bleeding without heparin calcium. Results The overall survival rate was 93.3%, which was higher than that of the control group (83.3%), but the difference was not statistically significant (P=0.569). The survival rate for subzones I and II by the Ishikawa subzone classification was 100%, whereas it was 87.5% in subzones III and IV. No statistically significant difference was observed. The rate of partial necrosis was 0% in subzones I and II, whereas it was significantly higher (66.7%) in subzones III and IV (P=0.015). The mean total blood loss via external bleeding was 588 g in 10 fingers. No patients required blood transfusion. Conclusions Congestion of a replanted fingertip can be successfully managed without blood transfusion by our method. Although complete relief from congestion in replants in subzones I and II is achievable, there is a higher risk of partial necrosis in subzones III and IV.

• Clinics in Shoulder and Elbow
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• 제18권3호
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• pp.120-127
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• 2015

Background: We prospectively compared the response to blind and ultrasound-guided glenohumeral injection of corticosteroids for treatment of shoulder stiffness. Methods: A total of 77 patients with shoulder stiffness between April 2008 and March 2012 were recruited. Patients were randomized to receive either a blind (group 1, n=39) or ultrasound-guided (group 2, n=38) glenohumeral injection of 40 mg triamcinolone. The clinical outcomes and shoulder range of motion (ROM) before injection, at 3, 6, and 12 months after injection and at the last follow-up were assessed. The same rehabilitation program was applied in both groups during the follow-up period. Results: There was no significant difference in demographic data on age, sex, ROM, and symptom duration before injection between groups (p>0.05). There were no significant differences in ROM including forward flexion, external rotation at the side, external rotation at $90^{\circ}$ abduction, and internal rotation, visual analogue scale for pain and functional outcomes including American Shoulder and Elbow Surgeons score, Simple Shoulder test between the two groups at any time point (p>0.05). Conclusions: Based on the current data, the result of ultrasound-guided glenohumeral injection was not superior to that of blind injection in the treatment of shoulder stiffness. We suggest that ultrasound-guided glenohumeral injection could be performed according to the patient's compliance and the surgeon's preference. Once familiar with the non-imaging-guided glenohumeral injection, it is an efficient and reliable method for the experienced surgeon. Ultrasound could be performed according to the surgeon's preference.

• 산업기술연구
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• 제32권A호
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• pp.65-70
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• 2012

Carboxy-guns are used for rapid and precise injection of $CO_2$ gas to the target skin area using external power source. In the design of carboxy-gun, the most important thing is how to precisely control injection volume of $CO_2$ gas. This paper deals with the control scheme of injection volume of carboxy-gun using solenoid valve. First the amount of volume that passes through the solenoid valve under on-off time ratio control is estimated based on the assumption of compressible gas flow. The flow rate of gas is experimentally measured under the varying pressure of the gas reservoir. Two results showed good correlation to each other, thus demonstrating the validity of the volume control strategy.

• 드라이브 ㆍ 컨트롤
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• 제9권3호
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• pp.1-7
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• 2012

This paper deals with the issue of model reference adaptive control strategy to control the injection molding machine. Prior to controller design, a pair of transfer functions are derived for the injection and dwelling process based on mathematical models of components. As external disturbances to examine the robustness of the proposed controller, nozzle clogging and contraction of molded objects are considered and realized by proportional valve. The overall simulation system, consisting of hydraulic components, controller and sensors, is implemented using the components of commercial software SimulationX. The simulation results confirm the proposed scheme's efficiency and robustness.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.535-538
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• 2008

Insert-injection molding can inject two different materials or two colors in the same mold and process. If this injection process use, product has ability because the base part maintain strength and specified part can inject soft-material. It makes the cost down by single operation automatically for saving wages. In this paper, we designed double-injection mold for automobile remote control to inject secondary using this part as insert after inject external appearance of product. CAE analysis was progressed gate location and runner size as variable and analysis result is reflected in mold design process. As a result, it could solved badness that is generated at the conventional mold. Additionally, cost is downed by reducing loss of runner as well as could omit painting process because surface of finished product is improved through new mold.

• ETRI Journal
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• 제34권5호
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• pp.690-695
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• 2012

We investigate the light-emitting performances of blue phosphorescent organic light-emitting diodes (PHOLEDs) with three different electron injection and transport materials, that is, bathocuproine(2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) (Bphen), 1,3,5-tri(m-pyrid-3-yl-phenyl)benzene (Tm3PyPB), and 2,6-bis(3-(carbazol-9-yl)phenyl)pyridine (26DCzPPy), which are partially doped with cesium metal. We find that the device characteristics are very dependent on the nature of the introduced electron injection layer (EIL) and electron transporting layer (ETL). When the appropriate EIL and ETL are combined, the peak external quantum efficiency and peak power efficiency improve up to 20.7% and 45.6 lm/W, respectively. Moreover, this blue PHOLED even maintains high external quantum efficiency of 19.6% and 16.9% at a luminance of $1,000cd/m^2$ and $10,000cd/m^2$, respectively.