Position Sensorless Control of BLDC Motors Based on Global Fast Terminal Sliding Mode Observer

Xiaoyuan Wang,Tao Fu,Xiaoguang Wang 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.6

The brushless DC motor (BLDCM) has many advantages. As a result, it is widely used in electric vehicle (EV) drive systems. To improve the reliability of the motor control system, a position sensorless control strategy based on a sliding mode observer (SMO) is proposed. The global fast terminal sliding mode observer (GFTSMO) is proposed to enhance the control performance of the SMO control system. The advantages of the linear sliding mode and the nonsingular terminal sliding mode (NTSM) are combined in the control strategy. The convergence speed of the system state is enhanced. The motor commutation point is obtained with the observation of the back EMF, and the instantaneous torque value of the motor is calculated. Therefore, the position sensorless control of the BLDCM is realized. Experimental results show that the proposed control strategy can improve the convergence speed, dynamic characteristics and robustness of the system.

Propagation Dynamics of a Finite-energy Airy Beam with Sinusoidal Phase in Optical Lattice

Xiaoyuan Huang,Manna Chen,Geng Zhang,Ye Liu,Hongcheng Wang 한국광학회 2020 Current Optics and Photonics Vol.4 No.4

The propagation of a truncated Airy beam with spatial phase modulation (SPM) is investigated in Kerr nonlinearity with an optical lattice. Before the truncated Airy beam enters the optical lattice, a sinusoidal phase is introduced on the wave-front of the beam. The effect of the spatial phase modulation and optical lattice on propagation behavior is analyzed by direct numerical simulation. It is found that the propagation direction of a truncated Airy beam can be effectively controlled by adjusting the values of phase shift. The effects of optical amplitude, truncation factor, spatial modulation frequency, lattice period and lattice depth on the propagation are discussed in detail. By choosing a high modulation depth, the finite-energy Airy beam can be deflected with a large deflection angle in an optical lattice.

Mediatory role of K, Cu and Mo over Ru/SiO2 catalysts for glycerol hydrogenolysis

Xiaoyuan Liao,Kewen Li,Xiaomin Xiang,Sheng-Guang Wang,Xichun She,Yulei Zhu,Yongwang Li 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.2

SiO2 supported ruthenium catalysts with and without modifiers were prepared, characterized and tested for glycerol hydrogenation. Addition of K, Cu and Mo affects the reducibility and acidity of the Ru/SiO2catalyst. Characterization data shows that Cu and Mo-modified Ru/SiO2 have stronger acidity. On the contrary, K element on a passive effect on the acidity of Ru based catalyst had been observed. A comparison with the pure Ru/SiO2 indicates the Cu-promoted specimen has better selective to the desired products, acetol, 1,2-propanediol and ethyl glycol, although the reactivity is slightly lower.

Fatty Acid Biosynthesis in Eukaryotic Photosynthetic Microalgae: Identification of a Microsomal Delta 12 Desaturase in Chlamydomonas reinhardtii

Xiaoyuan Chi,Xiaowen Zhang,Xiangyu Guan,Ling Ding,Youxun Li,Mingqing Wang,Hanzhi Lin,Song Qin 한국미생물학회 2008 The journal of microbiology Vol.46 No.2

Polyunsaturated fatty acids (PUFAs) are important components of infant and adult nutrition because they serve as structural elements of cell membranes. Fatty acid desaturases are responsible for the insertion of double bonds into pre-formed fatty acid chains in reactions that require oxygen and reducing equivalents. In this study, the genome-wide characterization of the fatty acid desaturases from seven eukaryotic photosynthetic microalgae was undertaken according to the conserved histidine-rich motifs and phylogenetic profiles. Analysis of these genomes provided insight into the origin and evolution of the pathway of fatty acid biosynthesis in eukaryotic plants. In addition, the candidate enzyme from Chlamydomonas reinhardtii with the highest similarity to the microsomal Δ12 desaturase of Chlorella vulgaris was isolated, and its function was verified by heterologous expression in yeast (Saccharomyces cerevisiae).

Awareness of Child Maltreatment among Professionals in Shanghai

Xiaoyuan Shang and Ilan Katz 한국사회복지학회 2015 Asian Social Work and Policy Review Vol.9 No.3

This study reports on a series of qualitative interviews with professionals in Shanghai, China who work with children. The interviews explored the awareness of child protection issues amongst a range of people who work with children, how they differentiate corporal punishment from maltreatment and what they would do in response to cases of child abuse. Shanghai has one of the most well developed child welfare systems in China, and compared to similar professionals in other cities, those in Shanghai had higher awareness and more training, but were nevertheless reluctant to intervene and did not feel well prepared to deal with cases of child abuse should they be encountered. However there are some indications that practice is improving, and examples of recent developments are provided

CRISPR/Cas9 Nuclease-Mediated Gene Knock-in in Bovine-Induced Pluripotent Cells

Xiaoyuan Quan,Jongpil Kim 한국동물생명공학회(구 한국동물번식학회) 2015 발생공학 국제심포지엄 및 학술대회 Vol.2015 No.10

On-going Research Activities to Mitigate Greenhouse Gas Emission from Paddy Fields in China

Xiaoyuan Yan 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

In vivo therapeutic success of microRNA-155 antagomir in a mouse model of pulmonary fibrosis induced by bleomycin

( Xiaoyuan Sun ),( Yu Kang ),( Shan Xue ),( Jing Zou ),( Jiabo Xu ),( Daoqiang Tang ),( Hui Qin ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.0

Background/Aims: MicroRNAs (miRNAs) play critical regulatory roles in the pathogenesis of pulmonary fibrosis. The aim of this study was to explore whether miRNA antagomirs could serve as potential therapeutic agents in interstitial lung diseases. Methods: A mouse model of pulmonary fibrosis was established by intratracheal injection of bleomycin (BLM). Using microarray analysis, up-regulated miRNAs were identified during the development of pulmonary fibrosis. miR-155 was chosen as the candidate miRNA. Fifteen mice were then randomized into the following three groups: BLM + antagomiR-155 group, treated with BLM plus intravenously injected with antagomiR-155; BLM group, treated with intratracheal BLM plus phosphate-buffered saline (PBS); and a control group, treated with PBS only. Lung tissues were collected for histopathological analysis, hydroxyproline measurement, and Western blotting. Enzyme-linked immunosorbent assays were used for the measurement of cytokines associated with pulmonary fibrosis. Results: Histological changes and hydroxyproline levels induced by BLM were significantly inhibited by antagomiR-155. The levels of interleukin 4 (IL-4) and transforming growth factor-β (TGF-β) expression were increased after BLM treatment. However, miR-155 silencing decreased the expression of IL-4, TGF-β, and interferon-γ. TGF-β-activated kinase 1/mitogen-activated protein kinase kinase kinase 7 (MAP3K7)-binding protein 2 (TAB2) of the mitogen-activated protein kinase (MAPK) signaling pathway, was activated by BLM and inhibited by in vivo silencing of miR-155 via antagomiR-155. Conclusions: In vivo treatment with antagomiR-155 alleviated the pathological changes induced by BLM and may be a promising therapeutic strategy for pulmonary fibrosis.

Book Review - The Pedagogy of English as an International Language : Perspectives from Scholars, Teachers and Students, by Roby Marlina and Ram Ashish Giri (Eds.), Dordrecht, Springer, 2014, 265 pp., 103.99 € (Hardcover), ISBN 978-3-319-06126-9

Xiaoyuan (Doris) Qu 아시아영어교육학회 2016 The Journal of Asia TEFL Vol.13 No.1

신흥국 기업 최고경영자의 정치적 연계가 국제인수합병 시 기업가치에 미치는 영향: 중국기업의 해외인수 분석

LI XIAOYUAN,박용석 한국국제경영학회 2020 國際經營硏究 Vol.31 No.2

The purpose of this study is to examine the impact of CEO political ties on the value of acquirers from emerging markets after cross-border mergers and acquisitions (CBM&As). No consistent findings on the relationship between CEO political ties and the value of cross-border acquirers exist in prior literature. Since CEO political tie can be a strategic resource for acquirers, while it also can lead conflicts of interest between politicians and shareholders, the impact of CEO political ties on the cross- border acquirer value is unclear. To clarify the effect of CEO political ties on the acquirer value after CBM&As, we apply an institutional perspective to analyse the moderating role of home and host market environment. In this study, 359 Chinese CBM&As between 2008 and 2016 are sampled to test our hypotheses. Test results show that Chinese acquirer CEO with political ties has lower stock returns after the announcement of CBM&A because the rent-seeking behavior from government leads the issue of principal-principal conflict. When the home region is more market-oriented, however, the negative correlation between CEO political ties and firm value is weakened after the announcement of CBM&As because investors would judge the firm behavior independent of political connections. By contrast, when the governance of the target country is more stable, the negative correlation between CEO political ties and firm value is strengthened after the announcement of CBM&As because acquirer CEOs with political ties would face greater obstacles when they do business in such country. The conclusion, implications, and limitations are discussed at the end of the paper. 본 연구는 신흥국 기업이 국제인수합병 시 최고경영자의 정치적 연계가 기업가치에 미치는 영향을 살펴보는데 그 목적을 두고 있다. 기존의 연구들에서는 국제인수합병 시 인수기업 최고경영자의 정치적 연계가 기업가치에 미치는 영향에 관해 혼재된 결과를 제시하였다. 국제인수합병 시 인수기업 최고경영자가 갖고 있는 정치적 연계는 전략적 자원으로서 투자자들에게 긍정적인 시그널을 주지만 정치적 연계로 인해 생기는 정부-기업간 이익충돌 문제는 투자자들에게 부정적인 시그널을 주기 때문이다. 따라서 신흥국 기업 최고경영자의 정치적 연계가 국제인수합병 시 기업가치에 미치는 영향을 보다 명확히 분석하기 위해 본 연구는 제도적 관점을 적용하여 시장 환경의 조절효과를 보여준다. 본 연구는 중국 상장기업이 2008년부터 2016년까지 진행한 국제인수합병 359개 사례를 표본으로 실증연구를 진행하였다. 그 결과 국제인수합병 시 인수기업 최고경영자의 정치적 연계는 정부의 지대추구 행위(rent-seeking behavior)로 인해 정부와 기업 사이 주인간 갈등(principal-principal conflict) 문제를 일으켜 투자자들에게 부정적인 시그널을 주어 기업의 시장가치에 단기적으로 부정적인 영향을 미치는 것으로 나타났다. 하지만 중국 인수기업이 위치한 지역의 시장화 정도가 높을수록 투자자들은 정치적 연계와는 상관없이 기업의 행위를 더욱 객관적으로 판단할 수 있기 때문에 국제인수합병 시 최고경영자의 정치적 연계가 기업가치에 미치는 부정적인 영향은 약화되는 것으로 확인되었다. 반면 피인수기업이 위치한 투자국 거버넌스가 좋을수록 최고경영자의 정치적 연계는 인수기업의 부정적인 이미지를 부각하여 국제인수합병 시 최고경영자의 정치적 연계가 기업가치에 미치는 부정적인 영향은 강화되는 것으로 확인되었다. 본 연구의 결론과 시사점 그리고 한계점에 관해서는 논문 마지막 부분에 정리하였다.