A cost- benefit analysis of routes between the Trans-Korean and Trans-Siberian railways

Anno Eremina,손찬현 인하대학교 정석물류통상연구원 2010 JOURNAL OF INTERNATIONAL LOGISTICS AND TRADE Vol.8 No.2

Recently the route connecting the trans-Korean railway and the trans-Siberian railway has become of particular interest for many academics and policy-makers in East Asian countries. The extensive review of previous studies, however, reveals that literature on the subject is lacking solid analytical framework. Most studies are one-sided, focusing on the political aspects of the issue or paying little attention to the economic aspects of the problem. This study intends to develop an analytical framework through which the most efficient route among four major alternative routes connecting the trans-Korean and trans-Siberian railways can be identified. It attempts to assign priorities to the four alternative routes according to their level of economic efficiency. This study utilizes a simple cost-benefit analysis in evaluating the four routes. Cost side,transportation time, effectiveness of customs procedures, and gauge difference are selected as the main economic factors. The volume of cargo, industrial production in adjacent regions, access to natural resources, and market size and foreign investment climate are used to evaluate the benefits of the routes. The study concludes that Route 3, which connects ‘Busan - Seoul (South Korea)– Pyongyang -Sinuiju (North Korea)– Shenyang– Beijing - Erenhot (China)– Ulaanbaatar (Mongolia)– Ulan-Ude -Moscow (Russia)’ is the most efficient route.

Gain Design of an Adaptive Full-order Observer Using a Pole Placement Technique for Speed Sensorless Induction Motor Drives

Anno Yoo,Sang-Heon Han,Young Ik Son,Young-Doo Yoon,Chanook Hong 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

This paper proposes a design guideline for the feedback gain of the adaptive full-order observer in the speed sensorless control of induction machines. The performance of the adaptive full-order observer is dependent on its feedback gain. This paper presents a pole placement method for the observer feedback gain design to improve the estimation performance of the speed adaptive observer. In the proposed method, the observer poles can be chosen independently of the induction motor poles. Instead, they can be positioned according to the operating speed. An analysis and experimental results obtained with the proposed method reveals better performances under general operating conditions.

Design of Flux Observer Robust to Interior Permanent-Magnet Synchronous Motor Flux Variation

Anno Yoo,Seung-Ki Sul IEEE 2009 IEEE transactions on industry applications Vol.45 No.5

<P>This paper presents a modified flux observer which is robust to the variation of the permanent-magnet flux linkage of an interior permanent-magnet synchronous motor (IPMSM). The IPMSM is driven by a current-regulated inverter, where the <I>d</I>-<I>q</I> axis currents are controlled by two proportional and integral controllers with feedforward cross-coupling decoupling terms. The integrator outputs of the current regulator reflecting flux errors are used to compensate the flux variation according to the operating temperature and manufacturing tolerance. The proposed flux observer shows satisfactory performance not only in maximum torque per ampere operating region but also in flux weakening region. The experimental results reveal the effectiveness of the proposed observer.</P>

Robust On-line Rotor Time Constant Estimation for Induction Machines

Anno Yoo 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.5

This paper proposes an on-line rotor time constant estimation strategy for indirect field oriented induction machines. The performance of the indirect field oriented control is dependent especially on the rotor time constant whose value varies according to the temperature. The proposed method calculates the difference between the nominal rotor time constant and the real value from the d- and q-axis integration terms of a proportional integral (PI) current regulator and the demanded voltages of the induction machine to regulate the current in the steady state. Because the proposed strategy has a simple structure and is available in wide speed and torque ranges, the proposed method can be easily used in the industrial field. The effectiveness of proposed strategy is verified with simulations and a 7.5kW experimental setup.

Analysis of High-Frequency Power Conversion for Series-connected Universal Link AC/DC Power Converter

Anno Yoo,Kyeongseo Kim,Seung-Ki Sul 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper proposes a novel circuit topology for AC/DC power converter based on a high frequency universal link. And the operation principles of the circuit are presented. The proposed power converter has small capacitances at DC-links. The reactive components are minimized, and the circuit has advantage of the reduced volume and increased efficiency. Even though the voltage of the 1<SUP>st</SUP> DC-link is rectified version of input AC voltage and it is variable, the magnitude of series-connected output voltage is constant on the average sense thanks to so called “sine modulation”. The demanded power is transferred by the phase-shift control between the series-connected sinemodulated voltage and the constant 2<SUP>nd</SUP> DC-link voltage. The presented analysis derives the power transfer equation with high-frequency components and some experimental results show the validity of the analysis and the performance of the circuit.

Novel Speed and Rotor Position Estimation Strategy Using a Dual Observer for Low-Resolution Position Sensors

Anno Yoo,Seung-Ki Sul,Dong-Cheol Lee,Cha-Seung Jun IEEE 2009 IEEE transactions on power electronics Vol.24 No.12

<P>Recently, high-performance AC motor drive technologies, including field-oriented control (FOC), have been widely used in home appliance products such as direct-drive drum washing machines. In low-cost AC machine drive systems, speed or position sensors with high resolution are not available due to high costs. Instead, a low-resolution sensor is installed to calculate the speed and rotor position. In the FOC, however, accurate rotor angle information is essential for high performance. In addition to the low resolution of the sensor, its accuracy is poor due to mechanical errors and signal processing. The inaccurate and delayed position information degrades the performance of current regulation and also increases torque ripples, which is the source of mechanical vibration and acoustic noise. In order to overcome this hardware problem, this study proposes a software technique based on a novel dual observer and a position sensor offset compensation strategy. The dual observer can estimate the rotor speed and position without time delay or bumps. Also, with the compensation algorithm for position sensor offset, the misaligned synchronous reference frame d- and q-axis can be corrected. Experimental results verify the effectiveness of the proposed method.</P>

직렬 연결 고주파 변압기를 가지는 교류/직류 전력변환 회로

유안노(Anno Yoo),김명호(Myoungho Kim),설승기(Seung-Ki Sul) 전력전자학회 2010 전력전자학술대회 논문집 Vol.2010 No.7

본 논문에서는 계통 연계가 가능한 새로운 교류/직류 전력변환 장치를 제안한다. 제안된 전력변환 회로는 정현파의 입력상 전류를 가지고, 양방향 전력 전달이 가능하며, 역률 제어가 가능하다는 장점으로 인하여 계통 연계형 전력변환 장치로 적합하다. 특히 제안된 전력변환 장치는 무효전력 소자의 사용을 최소화하여 시스템의 신뢰성을 증대시키고, 전기적 절연을 고주파 변압기를 통하여 얻도록 하여 시스템의 부피를 줄일 수 있다는 장점을 갖는다. 본 논문에서는 제안된 전력변환 회로의 구성 방법과 각 부분 별 동작에 대해서 기술하였으며 실험 장치를 구성하여 그 타당성을 입증하였다.

Gain Design of an Adaptive Full-order Observer Using a Pole Placement Technique for Speed Sensorless Induction Motor Drives

Yoo, Anno,Han, Sang-Heon,Son, Young Ik,Yoon, Young-Doo,Hong, Chanook The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

This paper proposes a design guideline for the feedback gain of the adaptive full-order observer in the speed sensorless control of induction machines. The performance of the adaptive full-order observer is dependent on its feedback gain. This paper presents a pole placement method for the observer feedback gain design to improve the estimation performance of the speed adaptive observer. In the proposed method, the observer poles can be chosen independently of the induction motor poles. Instead, they can be positioned according to the operating speed. An analysis and experimental results obtained with the proposed method reveals better performances under general operating conditions.

日本における韓流

阿武正英 ( Anno Masahide ) 한국일본근대학회 2017 일본근대학연구 Vol.0 No.55

本稿は日本における韓流について、2015年に京都市內の10代から50代までの8人の女性を對象に調査した結果をまとめたものである。日本國內で「韓流は終った」などという否定的な言說が多く見られるなかで、中高年女性の韓流ファンも健在であることと、想像以上にアクチュアルに韓流を享受している若者を發見できた。これまでの日本における韓流硏究は中高年女性の受容形態を分析するものが多かったが、若者の受容形態をさらに調査、分析する必要があるのではないかと思った。 また、韓流という鏡を介して映し出される日本の現狀について考えることで、調査でも聞かれた家族や社會のなかでのコミュニケ一ションの不在や儒敎的な意識の喪失なども見えてくる。このような觀点から、現代日本文化を分析する上でも、韓流の硏究は無意味ではないだろう。 This essay settled the result that I investigated for eight women in Kyoto from the teens to 50 generations in 2015 about the Korean wave in Japan. In late years verbal explanation called "the Korean wave was over" is frequent in Japan. However, as a result of investigation, the Korean fan of the old and middle age woman enjoyed Korean contents without changing. And I understood that a youth enjoyed the Korean wave actively.The study of Korean wave in conventional Japan had many things which analyzed the reception form of the old and middle age woman, but thought that it might be necessary for an investigation to analyze the reception form of the youth more. In addition, the Korean wave in Japan plays a role as the mirror to project Japanese society on. Through the mirror, the Japanese problems such as the loss of absence of the communication in a family and the society asked even about the investigation and the Confucianism-like consciousness are seen. The Study of Korean wave will not be meaningless after analyzing modern Japanese culture from such a point of view.

Robust On-line Rotor Time Constant Estimation for Induction Machines

Yoo, Anno The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.5

This paper proposes an on-line rotor time constant estimation strategy for indirect field oriented induction machines. The performance of the indirect field oriented control is dependent especially on the rotor time constant whose value varies according to the temperature. The proposed method calculates the difference between the nominal rotor time constant and the real value from the d- and q-axis integration terms of a proportional integral (PI) current regulator and the demanded voltages of the induction machine to regulate the current in the steady state. Because the proposed strategy has a simple structure and is available in wide speed and torque ranges, the proposed method can be easily used in the industrial field. The effectiveness of proposed strategy is verified with simulations and a 7.5kW experimental setup.