컨테이너 검색기 이송대차 추진용 선형 유도전동기의 2차측 리액션플레이트 재질에 따른 특성 연구

정재훈(Jae-Hoon Jeong),최장영(Jang-Young Choi),성소영(So-Young Sung),박종원(Jong-Won Park),임재원(Jaewon Lim) 대한전기학회 2016 전기학회논문지 Vol.65 No.1

This paper presents the analysis of the analysis of thrust characteristics of linear induction motors(LIMs) according to secondary reaction plate. LIMs are well known as high speed transport systems, which can obtain thrust directly without gears and links, or auxiliary mechanisms. A simple structure, easy maintenance, and less environmental pollution are advantages of LIMs. In transport systems using LIMs, the secondary reaction plate is an important design factor, because it has considerable impact on the cost of the railway as well as the performance of the LIMs. This paper deals analyzed the characteristics of linear induction motor used for moving the vehicle of container scanner. Thrust, efficiency and load characteristic were interpreted with FEM regarding two models whose material of secondary reaction plate was copper and aluminum. It suggested the interpretation of thrust, efficiency and power factor characteristic along slip and compared the operation ability of linear induction motor through characteristics analysis along the load.

Thrust Analysis and Experiments on Low-Speed Single-Sided Linear Induction Motor

Jae-Hoon Jeong,Jang-Young Choi,So-Young Sung,Jong-Won Park,Jaewon Lim 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

When the characteristics of a linear induction motor (LIM) are analyzed using finite element analysis (FEA), it is desirable to set the voltage source as an input. If the voltage source is set as an input in FEA, the leakage inductance and primary resistance of the equivalent circuit must be entered by direct calculation, and the magnetizing inductance and secondary reaction effects are directly considered in FEA. Exact calculation is necessary because the primary winding resistance and leakage inductance directly entered will have a significant effect on the LIM output. Therefore, in this study, we accurately calculated the primary leakage inductance and analyzed the resulting LIM characteristics. We calculated the leakage inductance using an analytical equation and FEA, and we confirmed the accuracy by comparing the results with the value experimentally calculated using a manufactured model. We also analyzed the instrument performance and thrust of the LIM as a function of the difference in the leakage inductance. Finally, we present the conclusions on the precise analysis based on the calculation of the leakage inductance.

A Study on Optimal Operating Point of Linear Induction Motor Considering Normal Force and Efficiency in MAGLEV Vehicle

Lim, Jaewon,Park, Doh-Young,Jeong, Jae-Hoon IEEE 2018 IEEE transactions on magnetics Vol.54 No.11

<P>This paper presents the electromagnetic characteristics of a linear induction motor (LIM) for a semi-high-speed magnetic levitation or maglev vehicle. The propulsion system of the maglev train provides excellent ride quality, but still has a disadvantage in that the propulsion efficiency is low owing to its inherent characteristics. In particular, in the propulsion system of maglev trains with a relatively large air gap, the increase in the propulsion efficiency remains an important issue. The propulsion system generates a vertical force during propulsion control. To ensure the stability of the propulsion system, the electromagnetic characteristics of the propulsion system’s vertical force need to be interpreted accurately. The normal force and thrust are analyzed with the finite-element method considering the varying speed and slip. To improve the propulsion efficiency, variable slip-frequency operation is proposed without deteriorating the levitation performance. The thrust map of the LIM with allowable slip frequency is also presented.</P>

자기부상열차 선형견인전동기의 직선형 및 아크형 모델에 따른 추력 특성 비교

임재원(Jaewon Lim),정재훈(Jae-Hoon Jeong),박도영(Doh-Young Park) 한국자동차공학회 2016 한국자동차공학회 부문종합 학술대회 Vol.2016 No.5

Thrust Analysis and Experiments on Low-Speed Single-Sided Linear Induction Motor

Jeong, Jae-Hoon,Choi, Jang-Young,Sung, So-Young,Park, Jong-Won,Lim, Jaewon The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

When the characteristics of a linear induction motor (LIM) are analyzed using finite element analysis (FEA), it is desirable to set the voltage source as an input. If the voltage source is set as an input in FEA, the leakage inductance and primary resistance of the equivalent circuit must be entered by direct calculation, and the magnetizing inductance and secondary reaction effects are directly considered in FEA. Exact calculation is necessary because the primary winding resistance and leakage inductance directly entered will have a significant effect on the LIM output. Therefore, in this study, we accurately calculated the primary leakage inductance and analyzed the resulting LIM characteristics. We calculated the leakage inductance using an analytical equation and FEA, and we confirmed the accuracy by comparing the results with the value experimentally calculated using a manufactured model. We also analyzed the instrument performance and thrust of the LIM as a function of the difference in the leakage inductance. Finally, we present the conclusions on the precise analysis based on the calculation of the leakage inductance.

Upregulation of TNF-α by Triglycerides is Mediated by MEK1 Activation in Jurkat T Cells

Jaewon Lim,Eun Ju Yang,Jeong Hyun Chang 대한의생명과학회 2018 Biomedical Science Letters Vol.24 No.3

Triglyceride (TG) is known to be associated with inflammatory disease including atherosclerosis. In a variety of atherosclerosis models, T lymphocytes are localized in the earliest lesions of atherosclerosis. T cell associated cytokines such as TNF-α and IFN-γ have pre-dominant inflammatory effects in chronic vascular diseases. In our previous study, we found that the expression of TNF-α and its receptor, TNF-αR was increased when Jurkat T lymphocyte cell lines were exposed to TGs. Therefore, experiments were conducted to determine which cell signaling pathway are involved in the increase of TNF-α and TNF-αR expression by TGs. To identify signal transduction pathways involved in TG-induced upregulation of TNF-α, we treated TG-exposed Jurkat T cells with specific inhibitors for MEK1, PI3K, NF-κB and PKC. We found that inhibition of the MEK1 pathway blocked TG-induced upregulation of TNF-α. However, the expression level of TNF-αR did not change with any signal transduction inhibitor. Based on this observation, we suggest that increase of exogenous TG induces increase of TNF-α expression through MEK1 pathway in Jurkat T cells. In addition, it was confirmed that the increase of TNF-α and TNF-αR expression by TGs occurs via different pathways.

Rapid Molecular Diagnosis using Real-time Nucleic Acid Sequence Based Amplification (NASBA) for Detection of Influenza A Virus Subtypes

Jaewon Lim,In Soo Lee,Yoonjung Cho,Hyunwoo Jin,Yeonim Choi,Hyeyoung Lee,Tae Ue Kim 대한의생명과학회 2011 Biomedical Science Letters Vol.17 No.4

Influenza A virus of the Orthomyxoviridae family is a contagious respiratory pathogen that continues to evolve and burden in the human public health. It is able to spread efficiently from human to human and have the potential to cause pandemics with significant morbidity and mortality. It has been estimated that every year about 500 million people are infected with this virus, causing about approximately 0.25 to 0.5 million people deaths worldwide. Influenza A viruses are classified into different subtypes by antigenicity based on their hemagglutinin (HA) and neuraminidase (NA) proteins. The sudden emergence of influenza A virus subtypes and access for epidemiological analysis of this subtypes demanded a rapid development of specific diagnostic tools. Also, rapid identification of the subtypes can help to determine the antiviral treatment, because the different subtypes have a different antiviral drug resistance patterns. In this study, our aim is to detect influenza A virus subtypes by using real-time nucleic acid sequence based amplification (NASBA) which has high sensitivity and specificity through molecular beacon. Real-time NASBA is a method that able to shorten the time compare to other molecular diagnostic tools and is performed by isothermal condition. We selected major pandemic influenza A virus subtypes, H3N2 and H5N1. Three influenza A virus gene fragments such as HA, NA and matrix protein (M) gene were targeted. M gene is distinguished influenza A virus from other influenza virus. We designed specific primers and molecular beacons for HA, NA and M gene, respectively. In brief, the results showed that the specificity of the real-time NASBA was higher than reverse transcription polymerase chain reaction (RT-PCR). In addition, time to positivity (TTP) of this method was shorter than real-time PCR. This study suggests that the rapid detection of neo-appearance pandemic influenza A virus using real-time NASBA has the potential to determine the subtypes.

Analysis and Experimental Evaluation of Normal Force of Linear Induction Motor for Maglev Vehicle

Lim, Jaewon,Jeong, Jae-Hoon,Kim, Chang-Hyun,Ha, Chang-Wan,Park, Doh-Young IEEE 2017 IEEE transactions on magnetics Vol.53 No.11

<P>This paper presents the analysis and experimental of the effective normal force and power consumption in a maglev vehicle. A maglev vehicle employs the electromagnets as suspension and linear motors for propulsion. These components give the higher ride comfort but suffered from energy efficiency. Therefore, a vector control-based algorithm and various air gaps are employed to increase the propulsion efficiency and lower the system energy consumption. The effective levitation load according to the levitation gap and normal force of a linear induction motor is calculated by power consumption in a levitation system and compared with finite-element analysis results. The experiment is carried out with the full-scaled train in test line and the efficiency of a propulsion system is also presented.</P>

Design of an Electromagnet with Low Detent Force and its Control for a Maglev Super-speed Vehicle

Lim, Jaewon,Kim, C.H.,Han, J.B.,Han, H.S. The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.4

The vibration and noise caused by the dynamic interaction between electromagnetic suspension and the linear synchronous motor stator beneath a flexible guideway remain problems in designing attractive Maglev trains. One possible method to reduce the sources of vibration is to minimize the detent force in the linear synchronous motor that creates variations in both lift force and thrust. This paper proposes lowering detent force by using separated core instead of single united core. The magnet is designed to adapt to the deflected guideway at a speed of 550km/h. This study will analyze the electromagnetic field and control performance, and how they relate to lift forces and dynamic responses.

Triglyceride Up-regulates Expression of ABCG1 in PMA-induced THP-1 Macrophages Through Activation of JNK and p38 MAPK Pathways

Jaewon Lim,Sung Hoon Kim,Yeo Wool Kang,Byung Chul Jung,Hyun-Kyung Kim,Juyeon Lee,Dongsup Lee,Ki-Jong Rhee,Yoon Suk Kim 대한의생명과학회 2014 Biomedical Science Letters Vol.20 No.4

Triglyceride (TG) can cause death of macrophages and formation of foam cells thereby increasing inflammation in atherosclerotic plaques. Accumulation of cholesterol in macrophages is another critical event that promotes development of inflammatory cardiovascular diseases. Several proteins are known to transport intracellular cholesterol outside of the cell and these proteins are thought to be protective against atherosclerosis pathogenesis. It is unknown whether TG can affect cholesterol efflux in macrophages. In the current study, we examined mRNA expression levels of genes that promote efflux of cholesterol (ABCA1, ABCG1 and SR-B1). We found that TG treated THP-1 macrophages exhibited an increase in ABCG1 expression in a dose- and time-dependent manner. In contrast, the expression of ABCA1 and SR-B1 remained unchanged. To identify cell signaling pathways that participate in up-regulation of ABCG1, THP-1 macrophages were treated with various cell signaling inhibitors. We found that inhibition of the JNK and p38 MAPK pathway completely abrogated up-regulation of ABCG1 whereas inhibition of MEK1 further enhanced ABCG1 expression in TG treated THP-1 macrophages. Also, TG induced phosphorylation of JNK and p38 MAPK in THP-1 macrophages. These results suggest that TG may potentially influence cholesterol efflux in macrophages.