• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.193-197
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• 1998

Frozen shoulder is known as a self-limited disease. But, its long duration and pain nature can make the patients debilitative. And most patients cannot tolerate a chronically painful extremity and are concerned about the possibility of developing permanent dysfunction. In painful phase of frozen shoulder, some aggressive mordalties as like trigger point injection or suprascapular nerve block can beneficial to: reduce discomfort and pain. In order to document clinical results, we evaluated the results of 134 frozen shoulders treated with trigger point injection and/or suprascapular nerve block at Kyungpook National University Hospital, from January 1995 to April 1997. The treatment group was divided into 3 modalities: 17 cases in trigger point injection(TPI), 39 cases in suprascapular nerve block(SSB), and 78 cases in both methods. The supportive treatment including oral medication, heat and stretching exercise was also applied. The average age at the time of diagnosis was 57 years old and average follow-up time was 18 months. The results were as follows: Average time of significant improvement in pain was 9 days. Eighty-eight percent (119 cases) was improved in pain and range of motion after injecllion treatments; 82%(14/17) with TPI, 85%(33/39) with SSB, and 92%(72/78) with both. Early improvement of paih within 1 week was 72% in the treatment-responsive group, in which TPI group has 100% response(14/14) and sse has 94% response(31/33)

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.328-331
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• 2009

This paper presents the behaviors of transient and conventional grounding impedances of a 30m counterpoise according to the injection point of lightning impulse currents. As a result, the trend of the conventional grounding impedances measured as a function of risetime of impulse current is similar to the transient grounding impedance of counterpoise. The injection point of impulse current greatly influences on the transient grounding impedance characteristics of counterpoise. The transient grounding impedances strongly depend on the injection point and the rising time of impulse current and the soil characteristics.

• Journal of IKEEE
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• v.24 no.3
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• pp.867-876
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• 2020

This paper proposes a neutral-point voltage ripple reduction of high frequency injection sensorless control of IPMSM fed by a three-level inverter. The high frequency voltage injection method has been successfully applied to sensorless control for IPMSM at low speed region. In the process of high frequency voltage injection sensorless control for IPMSM, the neutral-point voltage ripple is increased. It should be reduced because it distorts the output current and decreases a life time of DC-link capacitor. The proposed method in this paper reduces the neutral-point voltage ripple by compensating the reference voltage, and the compensation value is calculated simply with reference voltages and currents. The effectiveness of the proposed method is verified by simulation results.

• Journal of Ocean Engineering and Technology
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• v.13 no.3B
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• pp.38-46
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• 1999

Increasing stringent emissions legislation and requirement of more effective energy used for diesel engine demand the fine control of the fuel injection system. Recently, the electromagnetic fuel injection control system for diesel engine is tried to realize the optimum diesel combustion by the feel back sensing as optical signal of combustion flame. The photo detectors were made for the feed back signal of electromagnetic fuel injection control for small DI diesel engine. Their abilities to detect defining combustion events were examined. By evaluating test results, it was shown that the wider acceptable optical range design of optical probe window face, and selection of installation position and installation method of detector were important point for improving sensing ability. The detector was shown to detect start and end of diffused combustion and maximum point of flame intensity impossible for pressure sensor, and also shown that the maximum point of flame intensity was 75% of accumulated heat release point within the experimental conditions.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1633-1638
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• 2003

In case that in-leakage through the valve disk occurs, a numerical study is performed to estimate on thermal stratification phenomenon in the Safety Injection piping connected with the Reactor Coolant System piping of Nuclear Power Plant. As the leakage flow rate increases, the temperature difference between top and bottom of horizontal piping has the inflection point. In the connection point of valve and piping, the maximum temperature difference between top and bottom was 185K and occurred in the condition of 10 times of standard leakage flow rate. In the connection point of elbow and horizontal piping, the maximum temperature difference was 145K and occurred in the condition of 15 times of standard leakage flow rate. In the vertical piping of Safety Injection piping, the near of connection point between elbow and vertical piping showed the outstanding thermal stratification phenomenon in comparison with another region because of turbulent penetration from Reactor Coolant System piping. In order to prevent damage of piping due to the thermal stratification when in-leakage through the valve disk occurs, the connection points between valve and piping, and the connection points between elbow and piping need to be inspected continually.

• Journal of ILASS-Korea
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• v.28 no.2
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• pp.89-96
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• 2023

This study presents a numerical simulation investigating hydrodynamic characteristics of high-temperature hydrocarbon aviation fuel injected through a plain orifice injector. The analysis encompassed the temperature range up to the critical point, and the obtained results were compared with prior experimental observations. The analysis unveiled that the injector's exit pressure remains equivalent to the ambient pressure when the fuel injection temperature is below the boiling point. However, when the fuel temperature surpasses the boiling point, the exit pressure of the injector transitions to the saturated vapor pressure corresponding to the fuel injection temperature. Consequently, the exit pressure of the injector increases in tandem with the rapid increase of the saturation vapor pressure due to escalating fuel temperatures. This rise in the exit pressure necessitates a proportional increase in fuel injection pressure to ensure a fixed fuel mass flow rate. Furthermore, the investigation revealed that the discharge coefficient obtained by applying the exit pressure instead of the ambient pressure did exhibit no decrease, but rather was maintained at a nearly constant value, comparable to its level below the boiling point.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.9
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• pp.1198-1206
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• 1997

The flow characteristics of an intermittent fuel injection into a stationary ambient air were investigated using gasoline. The measurements were made by two-channel, air cooling type Phase Doppler Anemometer(PDA) system (DANTEC, 750 MW). And a pintle type injector of MPI (Multi-point Port Injection) system was utilized as a fuel injector. The PDA receiver optic was set up in a 60.deg. C forward scatter arrangement to obtain the optimum scattering signal of fuel droplets. The data were obtained by synchronizing PDA system with the fuel injection period, and the axial and radial velocity and turbulent components of fuel droplets were mainly measured for the analysis of temporal and spatial distribution depending upon the fuel injection pressures.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.811-815
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• 2005

We theoretically studied synchronization of chaotic oscillation in semiconductor lasers with chaotic light injection feed-back induced chaotic light generated from a master semiconductor laser was injected into a solitary slave semiconductor laser. The slave laser subsequently exhibited synchronized chaotic output for a wide parameter range with strong injection and frequency detuning within the injection locking scheme. We also analytically examined chaos synchronization based on a linear stability analysis from the view point of synchronization based on a linear stability analysis from the view point of modulation response of injection locked semiconductor lasers to chaotic light signal.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.2
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• pp.42-51
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• 2014

An experiment was conducted to study fuel injection characteristics of high boiling point test fuels (HBPTF), which are newly developed with higher boiling points than conventional aviation fuels, for various injection pressures when the fuel was heated to the temperature higher than their boiling points. The injection characteristics with elevating fuel temperature were quantified by the flow coefficient (${\alpha}$) and the cavitation number ($K_c$), and it was found that the trends between ${\alpha}$ and $K_c$ for various fuels were very similar with each other. In addition, compared with a conventional fuel, HBPTFs not only have higher fuel temperatures at which the effect of fuel boiling on the injection initiates, but also are less affected by the fuel boiling inside the injectors at temperatures over the boiling point.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.548-552
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• 2007

This research is the basic research to develop new anti-inflammatory medicine by feeding Scutellariae Radix extract to lipopolysaccharide(LPS) exposed rats, and analyzed it's effect on inflammatory response by LPS derivation. As a result, Plasma interleukin-$1\beta(IL-1\beta)$ and Plasma interleukin-6(IL-6) concentration showed the highest point at 5h after LPS injection, and in this time, the concentration of $IL-1\beta$ and IL-6 in the Scutellariae Radix extract groups at 200mg/kg and 300mg/kg showed lower values than that of control group. Plasma tumor necrosis $factor-\alpha(TNF-\alpha)$ concentration after LPS injection showed the highest point at 2h and showed similar level till at 5h. $TNF-\alpha$ concentration at 2h after LPS injection showed the low value only in the Scutellariae Radix extract 300mg/kg group compared to others, and in 5h, the all Scutellariae Radix extract groups showed lower value than that of the control group. Plasma interleukin-10(IL-10) concentration increased at 2h after LPS injection and reached the highest at 5h. After LPS injection the IL-10 concentration at 2h, the Scutellariae Radix extract injection group at 300mg/kg showed higher value than that of the others, and in 5h after LPS injection, Scutellariae Radix extract 200mg and 300mg groups showed higher value than the control group. Concluding from the above results, in inflammatory response by LPS derivation, the Scutellariae Radix gives positive effect.