• Journal of Power System Engineering
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• v.18 no.6
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• pp.51-57
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• 2014

High pressure common rail injection technology has revolutionized the diesel industry. Over the last decade it has allowed engine builders to run higher injection pressures as much as above 1,300bar in order to increase engine efficiency, while reducing emissions. This common rail system has low pressure circuit which is consist of low pressure pump, cascade overflow valve and flow metering unit. The low pressure pump's purpose is to feed fuel oil to the high pressure pump. The cascade overflow valve keeps pressure in front of the metering unit constant and provides lubrication for the high pressure pump. The metering unit, known as the MPROP or fuel pressure regulator, regulates the maximum flow rate delivers to the rail. In this paper, we have investigated the performance characteristics of each components and total low pressure circuit of common rail system.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.67-73
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• 2013

This experimental work described the effect of flow control valve type on the performance of wobble plate type fuel pump for the stable DME fuel supply. In order to study this, different four types of flow control valves (ITV, SCV, IMV and MPROP) were installed on the wobble plate fuel pump, and fuel flow rate, torque, and temperature variation of pump were investigated under various operating conditions by using pump performance test system. It was revealed that wobble plate type fuel pump worked well with ITV and SCV control valve, and the flow rate and torque of fuel pump was in proportion to the value of valve open duty. The maximum flow rate and torque of fuel pump were achieved around the 50% duty of control valve. Temperature variation at all pump measuring points were under $60^{\circ}C$ which is acceptable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4473-4482
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• 2010

The examination of pulse, which is a typical palpation technique in the oriental medicine, has been used conventional analog system for discrimination of 28 pulses. However, the clipping phenomenon in the pulses, which used same feature extraction technique with ECG signals, has been occurred in analog system due to feature extraction method and over amplification from the input signals. It caused inaccurate to analyze the pulse signals. In this paper, we propose a digital filter design technique based on Prony's method for signal modeling and C-spline interpolation for feature extraction from pulse signal to compensate analog pulse detection system. In addition, we suggest a compensated electronic pulse detection system comprising new pulse analyzing algorithm and shape analysis technique for pulses, which were difficult to use in analog system. The feasibility for new proposed system has been confirmed comparing output signals between electronic pulse detection system having proposed filter design techniques with pulse analyzing algorithm and conventional analog system.