• 사회경제평론
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• 제31권2호
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• pp.105-126
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• 2018

본 논문은 마르크스 가치론의 이시적 단일체계 해석(TSSI)에 대한 두 가지 비판적 논점을 제시한다. 첫째, 일반적인 조건 하에서 마르크스주의 근본정리가 성립함을 보일 수 있는 것은 TSSI가 유일하다라는 TSSI 논자들의 주장과는 달리, 명목이윤 뿐만 아니라 실질이윤에 대한 두 개의 서로 다른 정의를 모두 고려할 경우, 마르크스주의 근본정리가 TSSI 내에서 성립하는지 여부는 결정되지 않는다. 둘째, 오키시오 정리 비판으로 제시된 클리만 (1996)의 수리모형에 대해, 오키시오 정리에서 중요한 요소인 기술변화의 비용절감 여부를 고려하지 않는다는 점이 기존 문헌에서 지적된 바 있는데, 본 논문에선 이를 수리적으로 확인하는 작업을 통해 클리만 모형의 기술변화는 비용절감적이지 않고 따라서 오키시오 정리에 대한 내재적 비판이라고 할 수 없다는 점을 보인다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.389-393
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• 2003

This paper describes the design of enhanced TSSI RF Power Detector which has wide dynamic range using switch and Log amp. This Power Detector consists of low and high gain loops, and they adaptively switched by output DC voltage which is proportioned to input power level. Because Power Detector needs to separate the channel, so architecture is heterodyne system having 70MHz intermediate frequency. This proposed RF Power Detector is settle to the satisfaction of Closed loop power control system for W-CDMA optic repeater, and the obtained dynamic range cover the higher than 50dB.

• Journal of Power Electronics
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• 제16권5호
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• pp.1791-1801
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• 2016

This paper considers a carrier based signal injection method for use in the three shunt sensing inverter (TSSI) for sensorless motor control. It also analyzes the loss according to the injection axis of the voltage signal. To remove both the phase current and rotor position sensors, a sensorless method and a phase current reconstruction method can be simultaneously considered. However, an interaction between the two methods can be incurred when both methods inject voltage signals simultaneously. In this paper, a signal injection based sensorless method with the 120° OFF Discontinuous PWM (DPWM) is implemented in a TSSI to avoid this interaction problem. Since one leg does not have a switching event for one sampling period in the 120° OFF DPWM, the switching loss is altered according to the injection axis. The switching loss in the d-axis injection case can be up to 32% larger than that in the q-axis injection case. Other losses according to the injection axis are also analyzed.

• 전력전자학회논문지
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• 제22권2호
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• pp.175-180
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• 2017

The measurement of three-phase current is important to control the instantaneous torque of a interior permanent magnet synchronous motor(IPMSM) using a three-phase inverter. Therefore, shunt resistors are used in low-cost motor-driving systems to measure three-phase current instead of additional current sensors that are too expensive for these systems. However, in certain regions of a space vector plane, shunt resistors cannot reconstruct three-phase current in high-speed driving mode. In this paper, predictive current control is used to compensate for the three-phase current in those regions, which results in a reduction of current ripple in a three-shunt sensing inverter(TSSI) and torque ripple in IPMSM.

• Environmental Engineering Research
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• 제21권2호
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• pp.152-163
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• 2016

Present study investigates the potential of cassava peel and rubber tree bark for the removal of Cr (VI) from aqueous solution. Removal efficiency of more than 99% was obtained during the kinetic adsorption experiments with dosage of 3.5 g/L for cassava peel and 8 g/L for rubber tree bark. By comparing popular isotherm models and kinetic models for evaluating the kinetics of mass transfer, it was observed that Redlich-Peterson model and Langmuir model fitted well ($R^2$ > 0.99) resulting in maximum adsorption capacity as 79.37 mg/g and 43.86 mg/g for cassava peel and rubber tree bark respectively. Validation of pseudo-second order model and Elovich model indicated the possibility of chemisorption being the rate limiting step. The multi-linearity in the diffusion model was further addressed using multi-sites models (two-site series interface (TSSI) and two-site parallel interface (TSPI) models). Considering the influence of interface properties on the kinetic nature of sorption, TSSI model resulted in low mass transfer rate (5% for cassava peel and 10% for rubber tree bark) compared to TSPI model. The study highlights the employability of two-site sorption model for simultaneous representation of different stages of kinetic sorption for finding the rate-limiting process, compared to the separate equilibrium and kinetic modeling attempts.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 전력전자학술대회 논문집
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• pp.99-100
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• 2016

In a AC motor used by three phase inverter, the phase current must be measured to control instantaneous torque. It is expensive to use current sensor for measuring current in low cost motor. So, shunt resistor is used to measure current. But, the method sensing the phase current using shunt resistor cannot perform the vector control in high speed because of the area that impossible to restore three phase current. In this paper, predictive current is proposed for reconstructing the current in the impossible current sensing area that reduce the current ripple in TSSI(Three shunt sensing inverter) for PMSM.

• 한국통신학회논문지
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• 제16권12호
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• pp.1300-1312
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• 1991

본 논문에서는 단일버퍼 스위치에서 다중스롯호의 수용에 따른 타임스롯 순서보전을 알아보고, 타임스롯 순서보존을 고려하여 트래픽혼합비의 변화와 타임스롯의 랜덤 탐색횟수의 변화, 그리고 타임스롯의 랜덤탐색방법에 따른 호종별 호손율 톡성을 분석하였다. 이 결과는 TDX IA/B 교환기와 같은 단일 버퍼형식의 스위치망의 구성시 활용될 수 있을 것이다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.224-225
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• 2016

매입형 영구자석 전동기에 가격과 부피를 줄이기 위해 3개의 션트 저항을 이용하는 인버터를 사용하였고 회전자 위치센서를 제거하기 위해 모델기반 센서리스 기법을 사용하였다. TSSI (Three Shunt current Sensing Inverter)의 문제점인 특정 전압 이상에서는 전류를 검출할 수 없는 영역이 생기게 된다. 이를 예측전류를 사용하여 전류복원 불가영역을 개선하였다.