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Asteroseismology of the DBV star CBS 114

Research in Astronomy and Astrophysics 2016年第8期16卷 17-24页

作者： yan-hui chen Institute of Astrophysics Chuxiong Normal University School of Physics and Electronical Science Chuxiong Normal University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

Asteroseismology is a unique and powerful tool to investigate the internal structure of stars. CBS 114 is the sixth known pulsating DBV star. It was observed by Handler, Metcalfe, ＆ Wood at the South African Astronomical Observatory over three weeks in 2001. Then, it was observed by Metcalfe et al. for seven nights （2004 Feb. 19-25） on the 1.8 m telescope at the Bohyunsan Optical Astronomy Observatory and seven nights （2004 Feb. 21-27） on the 2.1 m telescope at the McDonald Observatory. Totally two triplets, four doublets, and five singlets were identified. The frequency splitting values are very different, from 5.2 *** to 11.9 ~tHz, which may reflect differential rotations. We evolve grids of white dwarf models by MESA. Cores, added with He/C envelopes, of those white dwarf models are inserted into WDEC to evolve grids of DBV star models. With those DBV star models, we calculate eigenperiods. Those calculated periods are used to fit observed periods. A best-fitting model is selected. The parameters are T^ff ----- 25 000 K, M, = 0.740 MG and log（MHe/M,） = -4.5. With the relatively large stellar mass, the effective temperature is close to the previous spectroscopic result. In addition, kinetic energy distributions are calculated for the best-fitting model. We find that the observed modes with large frequency splitting values are fitted by the calculated modes with a large amount of kinetic energy distributed in the C/O core. After preliminary analysis, we suggest that the C/O core may rotate at least two times faster than the helium layer for CBS 114.

关键词： stars: oscillations (including pulsations) -- stars: individual (CBS 114) -- white dwarfs

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Asteroseismology of DAV white dwarf stars and G29–38

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Research in Astronomy and Astrophysics 2013年第12期13卷 1438-1444页

作者： yan-hui chen yan Li Yunnan Astronomical Observatory Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

Asteroseismology is a powerful tool used for detecting the inner structure of stars, which is also widely used to study white dwarfs. We discuss the asteroseismology of DAV stars. The period-to-period fitting method is discussed in detail, including its reliability in detecting the inner structure of DAV stars. If we assume that all observed modes of some DAV stars are the l = I cases, the errors associated with model fitting will be always large. If we assume that the observed modes are com- posed of I = 1 and 2 modes, the errors associated with model fitting in this case will be small. However, there will be modes identified as l = 2 that do not have ob- served quintuplets. G29-38 has been observed spectroscopically and photometrically for many years. Thompson et al. made 1 modes identifications in the star through the limb darkening effect. With 11 known I modes, we also study the asteroseismology of G29-38, which reduces the blind l fittings and is a fair choice. Unfortunately, our two best-fitting models are not in line with the previous atmospheric results. Based on factors like only a few observed modes, stability and identification of eigenmodes, identification of spherical degrees, construction of physical and realistic models and so on, detecting the inner structure of DAV stars by asteroseismology needs further development.

关键词： stars: oscillations (including pulsations) - stars: individual (G29-38)- white dwarfs

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Commentary review on peripapillary morphological characteristics in high myopia eyes with glaucoma:diagnostic challenges and strategies

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International Journal of Ophthalmology(English edition) 2021年第4期14卷 600-605页

作者： yan-hui chen Rui-Hua Wei yan-Nian hui Tianjin International Joint Research and Development Centre of Ophthalmology and Vision Science Tianjin 300070China Eye Institute and School of Optometry Tianjin Medical University Eye HospitalTianjin 300384China Department of Ophthalmology Xijing HospitalFourth Military Medical UniversityXi’an 710023Shaanxi ProvinceChina

The incidences of open angle glaucoma(OAG)and high myopia are increasing *** the aging population and concurrent rapid increase in the number of individuals with myopia,the risk of visual defects caused by highly myopic OAG is likely to increase dramatically over the next few ***,precise screening and diagnosis of OAG is challenging because of the tilt and rotation of the optic disc,as well as extensiveβ-zone parapapillary atrophy in highly myopic *** advances in optical coherence tomography(OCT)and OCT angiography(OCTA)technologies imply that both modalities are promising tools for the detection of highly myopic ***,the diagnosis of OAG remains to be determined with the longitudinal changes of functional damages(*** field defect,visual electrophysiological changes).We herein describe some aspects of microvascular and microstructural pathology in patients with highly myopic OAG and proposes a framework for the development of novel diagnostic and therapeutic strategies.

关键词： high myopia open angle glaucoma parapapillary atrophy parapapillary microvasculature optic disc lamina cribrosa optical coherence tomography

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Optimization of the resonant frequency servo loop technique in the resonator micro optic gyro

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 942-950页

作者： yang REN Zhong-he JIN yan chen hui-lian MA Department of Information Science ＆ Electronic Engineering Zhejiang University Hangzhou 310027 China

Proportional integrator (PI) is always adopted in the resonant frequency servo loop in a resonator micro optic gyro (RMOG). The oscillation phenomenon is observed when adjusting the loop gain surpassing a threshold. This phenomenon limits system performance on step response speed and residual error. Based on the experiment system, a simulation model was set up. Further analysis shows that the threshold gain is related to the system loop filter setting and the loop delay. The traditional PI frequency servo loop technique in the RMOG system cannot keep up with the environment's disturbance quickly enough, which leads to a large residual error. A compensating method is proposed to optimize the tracking performance, solve the oscillation problem, and speed up the system response. Simulation and experiment results show that the compensated system is superior in performance. It has less residual error in the stable state and is 10 times quicker than the uncompensated system on the step response.

关键词： Resonator micro optic gyro (RMOG) Resonance frequency servo loop Phase compensating method

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Correction to:Green Vertical-Cavity Surface-Emitting Lasers Based on InGaN Quantum Dots and Short

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Nano-Micro Letters 2024年第4期16卷 432-432页

作者： Tao yang yan‑hui chen Ya‑Chao Wang Wei Ou Lei‑Ying Ying yang Mei Ai‑Qin Tian Jian‑Ping Liu Hao‑Chung Kuo Bao‑Ping Zhang Laboratory of Micro/Nano‑Optoelectronics School of Electronic Science and EngineeringXiamen UniversityXiamen 361005FujianPeople’s Republic of China Suzhou Institute of Nano‑Tech and Nano‑Bionics Chinese Academy of SciencesSuzhou 215123JiangsuPeople’s Republic of China Department of Photonics National Yang Ming Chiao Tung UniversityHsinchu 30010TaiwanPeople’s Republic of China Semiconductor Research Center Honhai Research InstituteNew Taipei 220236TaiwanPeople’s Republic of China

Correction to:Nano-Micro Lett.(2023)15:223 https://***/10.1007/s40820-023-01189-0 In this article the author’s name“Hao-Chung Kuo”was incorrectly written as“Hao-Chung Guo”.And in the last sentence of the first pa... 详细信息

关键词： And has sentence

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An iterative linear quadratic regulator based trajectory tracking controller for wheeled mobile robot

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第8期13卷 593-600页

作者： Hao-jie ZHANG Jian-wei GONG yan JIANG Guang-ming XIONG hui-yan chen Intelligent Vehicle Research Center Beijing Institute of TechnologyBeijing 100081China

We present an iterative linear quadratic regulator(ILQR) method for trajectory tracking control of a wheeled mobile robot *** proposed scheme involves a kinematic model linearization technique,a global trajectory generation algorithm,and trajectory tracking controller design.A lattice planner,which searches over a 3D(x,y,θ) configuration space,is adopted to generate the global *** ILQR method is used to design a local trajectory tracking *** effectiveness of the proposed method is demonstrated in simulation and experiment with a significantly asymmetric differential drive *** performance of the local controller is analyzed and compared with that of the existing linear quadratic regulator(LQR) *** to the experiments,the new controller improves the control sequences(v,ω) iteratively and produces slightly better ***,two trajectories,'S' and '8' courses,are followed with sufficient accuracy using the proposed controller.

关键词： Lattice planner Global trajectory Kinematic model Trajectory tracking controller Iterative linear quadratic regulator (ILQR)

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Clinical manifestations and prenatal diagnosis of Ullrich congenital muscular dystrophy: A case report

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World Journal of Clinical Cases 2022年第1期10卷 338-344页

作者： Jun Hu yan-hui chen Xin Fang Yu Zhou Feng chen Department of Pediatrics Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Obstetrics and Gynecology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Pediatric Surgery Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND Ullrich congenital muscular dystrophy(UCMD)is one of the collagen-VI-related myopathies caused by mutations of COL6A1,COL6A2,and COL6A3 *** individuals are characterized by muscle weakness,proximal joint contracture,distal joint hyperlaxity,and progressive respiratory *** is currently no cure for ***,we report the clinical manifestations and prenatal diagnosis of compound heterozygous mutations of the COL6A2 gene in a Chinese family with *** SUMMARY A 3-year-old boy,his 4-year-old brother,their parents,and a 20-wk-old fetus in the mother’s womb were included in the *** brothers had the typical manifestations of the early-severe subtype:A delayed motor milestone(never walking independently),torticollis,scoliosis,proximal joint contracture,distal joint hyperextension,right hip joint dislocation,and calcaneal *** brothers were found by whole-exome sequencing and Sanger sequencing to carry two mutations of the COL6A2 gene(c.1353_c.1354insC,***453Profs-Ter42/c.2105G>A,***702Ter).The absence of collagen VI staining in the younger brother’s muscle was identified *** counseling and prenatal diagnosis were crucial for the family,as the autosomal recessive genetic disease affected a quarter of the patient’s *** fetus of the mother’s third child underwent prenatal diagnosis and carried the same two mutations of COL6A2,confirmed in the amniotic fluid by multiplex ligation-dependent probe amplification and short tandem *** a painful psychological struggle,the parents finally decided to terminate the *** We report a Chinese family suffering from *** clarifying the COL6A2 mutations in the probands,the parents had the opportunity to opt for voluntary interruption of the third UCMD pregnancy.

关键词： Ullrich congenital muscular dystrophy COL6A2 Mutation Prenatal diagnosis Case report

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The rate of period change in DAV stars

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Research in Astronomy and Astrophysics 2017年第7期17卷 11-24页

作者： yan-hui chen Cai-Yun Ding Wei-Wei Na Hong Shu Institute of Astrophysics Chuxiong Normal University School of Physics and Electronical Science Chuxiong Normal University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences School of Physics and Electronic Engineering Yuxi Normal University

Grids of DAV star models are evolved by WDEC, taking the element diffusion effect into account. The grid parameters are hydrogen mass log（MH/M＊）, helium mass log（MHe/M＊）, stellar mass M＊and effective temperature T_（eff） for DAV stars. The core compositions are from white dwarf models evolved by MESA. Therefore, DAV star models evolved by WDEC have historically viable core compositions. Based on those DAV star models, we studied the rate of period change（P˙（k）） for different values of H, He, M_＊and Teff. The results are consistent with previous work. Two DAV stars G117-B15A and R548 have been observed for around 40 years. The rates of period change of two large-amplitude modes were obtained through the O-C method. We conducted an asteroseismological study on the two DAV stars and then obtained a best-fitting model for each star. Based on the two best-fitting models,the mode identifications（l, k） of the observed modes for G117-B15A and R548 are consistent with previous work. Both the observed modes and the observedP˙ s can be fitted by calculated ones. The results indicate that our method of evolving DAV star models is feasible.

关键词： stars oscillations (including pulsations) - stars individual (G117-B 15A and R548) -white dwarfs

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Properties of PA(polyamide) coating and PA/MoS2 composite coatings by flame spraying

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中国有色金属学会会刊：英文版 2004年第z1期14卷 67-71页

作者： XU Hai-yan ZHOU hui-di chen Jian-min FENG Zhi-zhong State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Lanzhou 730000 China Graduate School Chinese Academy of Science China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Lanzhou 730000 China

PA and PA/MoS2 composite coatings were prepared by flame-spraying. The thermal properties, crystallinity, microstructure and tribological properties were investigated with Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy(SEM), and MM-200 model wear tester. Temperature influences the final morphological structure of the coatings. Tribological experiment results indicate that the MoS2 filled PA coating has different wear resistance compared with the PA coating without MoS2 filler. A high content of MoS2 decreases the hardness of composite coating and enhances the wear rate. The 1 %-3% content of MoS2 has advantages to the tribological ProPerties of PA composite coatings.

关键词： flame spraying polymer coating wear filler

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A new sesquilignan from Selaginella sinensis (Desv.) Spring

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Chinese Chemical Letters 2007年第10期18卷 1224-1226页

作者： yan Zhi Wang hui chen Xiao Ke Zheng Wei Sheng Feng Henan College of Traditional Chinese Medicine Zhengzhou 450008 China

A new sesquilignan, namely sinensiol A, was isolated from the plant of Selaginella sinensis （Desv.） Spring. Its structure was identified on the basis of various spectroscopic data analysis.

关键词： Selaginella sinensis, Sinonsiol A Sesquilignan

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