• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.72.1-72
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• 1998

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.70-77
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• 2013

We suggest a low area and high efficiency switched-mode power supply (SMPS) with a pulse width modulation (PWM) generator based on a pseudo relaxation-oscillating technique. In the proposed circuit, the PWM duty ratio is determined by the voltage slope control of an internal capacitor according to amount of charging current in a PWM generator. Compared to conventional SMPSs, the proposed control method consists of a simple structure without the filter circuits needed for an analog-controlled SMPS or the digital compensator used by a digitally-controlled SMPS. The proposed circuit is able to operate at switching frequency of 1MHz~10MHz, as this frequency can be controlled from the selection of one of the internal capacitors in a PWM generator. The maximum current of the core circuit is 2.7 mA, and the total current of the entire circuit including output buffer driver is 15 mA at 10 MHz switching frequency. The proposed SMPS has a simulated maximum ripple voltage of 7mV. In this paper, to verify the operation of the proposed circuit, we performed simulation using Dongbu Hitek BCD $0.35{\mu}m$ technology and measured the proposed circuit.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.12 no.1
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• pp.71-81
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• 2017

Objectives : It is important to develop a new Chuna manual therapy as a representative of Chuna manual therapy technique at the time of KSCMM's (Korean Society of Chuna manual medicine) joining a $F{\acute{e}}d{\acute{e}}ration$ Internationale de $M{\acute{e}}decine$ Manuelle (FIMM). Therefore, Sunu manual therapy (SMT) will be introduced as a purely new Chuna manual therapy. Main subject : Sunu manual therapy (SMT) was discovered about two decade ago by a Korean Medicine doctor who wanted to develop a new manual therapy to treat a internal disease. It is very important to make the best use of four powers such as a compression force, a torsion force, a bending force, a tension force using a resonance principle and to experience a feeling of spine axis. SMT is different from Chiropractic technique and Osteopathy technique, in that SMT could treat so many disease using only one technique, but other manual therapy could utilize so many technique to treat only one disease. Discussion : Because SMT utilize a power of a moving in silience, it will take several years to totally master a SMT which will make a patient and a doctor experience a feeling of spine axis. As a feeling of spine axis is deeper, a nerve could be excited and treated by a SMT. Also as a feeling of spine axis is shallower, a muscle could be excied and treated by a SMT. Conclusions : SMT could be classed as a craniosacral chuna therapy or visceral chuna therapy to treat a internal disease considering SMT's action and purpose.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.81-89
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• 2010

This study was conducted to evaluate the effects of early revegetation by analyzing the characteristics of germination and growth of Chrysanthemum zawadskii using vegetation-plant in rock slopes. After making up a growing basis of approximately 20-cm depth and 10-cm diameter by using a boring machine, the surface of rock slopes was planted with vegetation-plant. The number of germinating populations by soil media was 41 in H.s, 4 in T.s, 3 in M.s, and 0 in M.g.s. The germination rate (%) by soil media was 20.0% in H.s, 3.3% in T.s, 2.5% in M.s and 0% in M.g.s. In monthly changes of growth rate, the aspect was northwest direction, the soil media was H.s, and the treatment was microorganism plot. The main factors affecting survivorship and growth of population were soil media and treatment plot. The interaction between each factor had a good effects in bearing x treatment plot, soil media x treatment plot. but, it is recommended that the mulching of vegetation plant is highly needed to help the germination of seed and growth of vegetation because of loss of seed and soil media occurred due to rainfall. Therefore, The result suggests that the revegetation technique using boring in rock slope was very efficient in respect of the early revegetation and the landscape.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1177-1178
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• 2013

• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.118-121
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• 1992

This paper presents an optimal Fuzzy Control Technique to control the load frequency control of multiarea power system with a given stepwise load disturbance. The related simulation results show that the optimized fuzzy control technique are more effective than the conventional control technique (TBC, Optimal Control and etc) for reduction of load frequency deviation in transient and stedy-state, and for minimization of settling time.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.4
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• pp.29-36
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• 2012

In order to create a wind resource map, we need wind data, contour map and roughness map. Moving Filter technique was applied to Udo of Jeju Island to improve the accuracy and efficiency of creating roughness map based on the Land Cover Map of the Ministry of Environment. The Land Cover Map was simplified using moving filtering, and the roughness map was created with this Land Cover Map. The wind resource map was created using this roughness map. Finally, we verified the validity and application of moving filter technique for wind resource map. As a result, the wind map which was created using the roughness map with moving filtering showed bias values which were all negative. It means the wind map is underestimated to values of wind energy and RMSE values were also from 0.0237m/s to 0.0253m/s at 50m height. In other words, estimation of wind resource using image filtering provides reliable results at 80m height typically when the wind turbine is installed. Finally, we found that image filtering technique is very useful tool to make wind resource map.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.11a
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• pp.317-320
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• 2003

Nowadays, mobile is one of the leading technique fields. So when the company considers adapting CRM$^1$ through using mobile, the company can establish customer's satisfaction more efficiently. However, it hasn't been much studied in this filed of mobile although there has been remarkable advancement research on the technical area. When it comes to CRM in Korea, CBM is developed at the world status on the technique as well as service. And companies are realizing the importance of emerging customers market on their market strategy, so they are trying to attract new customers and also fasten loyal customers. This research will make us foresee and follow m-CRM trend and also give the companies how companies make a module appropriately for their strategy towards m-CRM$^2$.

• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.3
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• pp.109-117
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• 1993

A carbon/epoxy composite drive shaft used for the power transmission of the automobiles with steel joints. Compared with the metallic drive shaft, the composite one has the weight saving of 50% with equivalent torsional strength and fatigue characteristics. In this study, the filament winding technique for the composite tube and composite/metal joining technique are estabilished. The performance test of the drive shaft is carried out. The optimal condition of the surface roughness of the steel adherend was $1.5{{\mu}m}$ to $2.5{{\mu}m}$, and the optimal condition of the bonding thickness was 0.15mm. Maximum torque and torsional stiffness of the composite drive shaft manufactured by filament winding process were found to be $210kg{\cdot}m$ and $18.5kg{\cdot}m/deg$, respectively.

• Journal of Korea Foundry Society
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• v.17 no.5
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• pp.426-437
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• 1997