• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.431-432
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• 2008

In order to develop and inspect the electronic controller of propulsion system, It must emulate the electronic signal similar to actual signal. The applied signals on propulsion system are engine speed, turbine speed, various kinds of temperatue signal, pressure signal, LVDT/RVDT position signal and so forth. Contents are the development of emulator that simulate the electronic signals similar to actual signals.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.416-422
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• 2007

Prime movers in most large merchant ships adapt two stroke low speed diesel engine which has higher efficiency, mobility and durability. However, severe torsional vibration in these diesel engines may be induced by higher fluctuation of combustion pressures. Consequently, it may lead sometimes to propulsion shafting failure due to the accumulated fatigue stresses. Shaft fatigue strength analysis had been done traditionally in time domain but this method is complicated and difficult in analysing bi-modal vibration system such as the case of cylinder misfiring condition. In this paper authors introduce an assessment method of fatigue strength estimation for propulsion shafting system with two stroke low speed diesel engine in the frequency domain.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.11 no.1
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• pp.21-25
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• 1975

Authors studied the propulsion efficiency of G. T. 280 to 300 class tuna longliners used in Korea. At first authors calculated the ratios and factors of the ship by use of principal dimensions. In cordance with this ratios and factors authors, examined the effective horse power, propulsion ficiency and brake horse power, and following results are obtained. (1) EHP is slightly increased according to the increasing of Froude number and speed. (2) Value of propulsion coefficient is obtained in the range of 51-54% at the cruising speed an its average is 52% in 6-13 knot of the speed. (3) EHP and BHP are increased according to the increasing of prismatic coefficient at the same speed.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.6
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• pp.946-951
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• 2009

An induction motor based on DTC(Direct Torque Control) is being increasingly used in various industrial applications. DTC offers faster torque response and better speed control with lesser hardware and processing costs in compared with other controlled drives. This study was to evaluate performance of DTC for induction motor of electric propulsion ship. The simulation results indicated good speed and torque response from the low to middle speed range. Also, DTC has advantages such as the independency on motor parameter.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.576-588
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• 2000

The study was carried out about the design of the propulsion and the control systems for Korean High Speed Train. The propulsion system was studied to run the maximum operating speed of 350km/h, The capacity of the main equipment is decided for the train to run tile maximum operating speed of 350km/h with the configuration of 2 power cars, 4 motorized trailers and 14 intermediate trailers. The control system was studied to two parts the supply and the control of high and low voltages used at train, The performance study of control system would be continued to update through system analysis according to propulsion system developing.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.225-232
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• 2007

This work intends to investigate the effects of shift characteristics on the propulsion performance of a manual wheelchair with an automatic transmission. A planetary gear train is employed to generate a two-stage shift automatically, based on the distance traveled from rest. Motion analysis has been performed for measuring kinematic properties of the arm and then the inverse dynamics has been applied for estimating joint forces/torques. Then, a parametric study has been performed to find a set of the shift ratios and the shift intervals for optimizing propulsion performance. Results show that the propulsion performance is closely related to the shift condition. It is found that a short shift interval is desirable for a short distance propulsion. However, an optimum shift interval for a long distance propulsion is inversely proportional to the shift ratio approximately. Consequently, the automatic transmission can greatly lower the joint loadings by the speed reduction, which eventually contribute to prevent joint injuries of wheelchair users.

• Journal of the Korean Society of Propulsion Engineers
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• v.7 no.3
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• pp.38-44
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• 2003

In this study, a performance model of the smart UAV propulsion system with ducts, tip jets and variable main nozzle, which has flight capability of the rotary wing mode for the take-off/landing and low speed forward flight as well as the fixed wing mode for high speed forward flight, has been newly developed With the proposed model, steady-state performance analysis was performed at various flight modes such as rotary wing mode, fixed wing mode, compound ing mode and altitude as well as at flight speed conditions. In investigation of performance analysis. it was noted that the operational capability of the propulsion system was limited due to the duct losses depending on each flight mode, and the limitation with the altitude variation case had much greater than that with the flight speed variation case.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.177-182
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• 2003

In this study, a performance model of the Smart UAV propulsion system with ducts, tip jets and variable main nozzle, which has flight capability of the rotary wing mode for the take-off/landing and low speed forward flight as welt as the fixed wing mode for high speed forward flight, has been newly developed. With the proposed model, steady-state performance analysis was performed at various flight modes and conditions, such as rotary wing mode, fixed wing mode, compound wing, mode altitude and flight speed. In investigation of performance analysis, it was noted that the operational capability of the propulsion system was limited due to the duct losses depending on each flight mode, and the limitation with the altitude variation case has much greater than that with the flight speed variation case.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.461-469
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• 2010

Up to now, High speed train was widely used in France, Germany and Japan. In korea, High speed train was introduced from France train model and operation was made in year 2004. With this high speed operation Know-How, HSR-350 train was developed with our own technology. And now KTX-II which was made by our own technology are running in commercial line. High speed rolling stock system acceleration technology is train propulsion system and this is composed with traction motor, Power transfer system and auxiliary power system. This paper, introduced the performance of the traction propulsion system and other equipment that has been installed at the KTX-II will be secured.

• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.200-206
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• 2012

In order to develop a deep-underground great train express (GTX) in South Korea, the specifications decision and development of a traction control system (including an inverter and a traction motor), which considers a variety of route conditions, must be advanced. In this study, we examined the running resistance properties of a high-speed traction system based on a variety of tunnel types and vehicle organization methods. Then, we studied the power requirements necessary for the traction motor to maintain balanced speed in the high-speed traction system. From this, we determined the design criteria for the development of a high-speed traction system for use in the deep-underground GTX. Finally, we designed a linear induction motor (LIM) for a propulsion system, and we used the finite element method (FEM) to analyze its performance as it travelled through deep-underground tunnels.