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Research on the principle of space high-precision temperature control system of liquid crystals based Stokes polarimeter

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Research in Astronomy and Astrophysics 2021年第1期21卷 97-104页

作者： Xin-Wei Zhang Yang Zhang Jia-Ben Lin jun-feng hou Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic *** crystals based Stokes polarimeter is a novel technology,and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China,Advanced Space-based Solar ***,the liquid crystals based Stokes polarimeter in space is not a mature ***,it is of great scientific significance to study the control method and characteristics of the *** retardation produced by a liquid crystal variable retarder is sensitive to the temperature,and the retardation changes 0.09°per 0.10℃.The error in polarization measurement caused by this change is 0.016,which affects the accuracy of magnetic field *** order to ensure the stability of its performance,this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in *** order to optimize the structure design and temperature control system,the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method,and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed *** analyzing the principle of highprecision temperature measurement in space,a high-precision temperature measurement circuit based on integrated operational amplifier,programmable amplifier and 12 bit A/D is designed,and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating *** experimental results show that the effect of temperature control is accurate and stable,whenever the liquid crystals based Stokes polarimeter is either in the air or *** temperature stability is within±0.0150℃,which demonstrates greatly improved stability for the liquid crystals based Stokes polarim

关键词： liquid crystals based Stokes polarimeter high-precision temperature measurement space high-precision temperature control temperature field analysis PID control

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Lossless Compression Method for the Magnetic and Helioseismic Imager(MHI)Payload

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Research in Astronomy and Astrophysics 2024年第4期24卷 214-221页

作者： Li-Yue Tong Jia-Ben Lin Yuan-Yong Deng Kai-Fan Ji jun-feng hou Quan Wang Xiao Yang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

The Solar Polar-orbit Observatory(SPO),proposed by Chinese scientists,is designed to observe the solar polar regions in an unprecedented way with a spacecraft traveling in a large solar inclination angle and a small ***,one of the most significant challenges lies in ultra-long-distance data transmission,particularly for the Magnetic and Helioseismic Imager(MHI),which is the most important payload and generates the largest volume of data in *** this paper,we propose a tailored lossless data compression method based on the measurement mode and characteristics of MHI *** background out of the solar disk is removed to decrease the pixel number of an image under *** predictive coding methods are combined to eliminate the redundancy utilizing the correlation(space,spectrum,and polarization)in data set,improving the compression *** results demonstrate that our method achieves an average compression ratio of *** compression time is also less than the general observation *** method exhibits strong feasibility and can be easily adapted to MHI.

关键词： methods:data analysis techniques:image processing Sun:magnetic fields Sun:photosphere

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Interference effect on the liquid-crystal-based Stokes polarimeter

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Chinese Physics B 2020年第12期29卷 286-296页

作者： jun-feng hou Dong-Guang Wang Yuan-Yong Deng Zhi-Yong Zhang Ying-Zi Sun Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The Stokes polarimeter based on liquid crystal variable retarders(LCVRs)is envisaged as a promising novel technique for polarization measurement in space applications due to the inherent advantage of eliminating the need for conventional rotating polarizing optics and increasing the measuring ***,the intrinsic multi-beam interference in LCVRs limits its polarization accuracy by several *** to eliminate the influence of the interference effect becomes an urgent issue for the liquid-crystal-based Stokes *** present study introduces a simplified but effective interference model based on the thin-film optics and polarized light theory to simulate the relationship between the interference effect of the LCVRs-based Stokes polarimeter and the polarization *** simulation results show that the transmittance variation of LCVR with the derived voltage is caused by multi beam interference between the indium tin oxide(ITO)film and the liquid crystal within LCVR,which produces a few percent of instrumental *** instrumental polarization is about 0.01 and different for different *** optimization method was proposed to reduce the instrumental polarization to 0.002,effectively improving the polarization sensitivity of the Stokes polarimeter limited by the *** addition,an experimental setup was built up to measure and analyze the influence of the interference effect of the LCVRs-based Stokes polarimeter on the polarization accuracy before and after the *** experiment results are in good agreement with the simulation.

关键词： polarimetry liquid crystal variable retarder(LCVR) interference effect

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Spectro-polarimetric observations at the NVST:*** polarization calibration and primary measurements

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Research in Astronomy and Astrophysics 2020年第4期20卷 7-18页

作者： jun-feng hou Zhi Xu Shu Yuan Yu-Chao Chen Jian-Guo Peng Dong-Guang Wang jun Xu Yuan-Yong Deng Zhen-Yu Jin Kai-Fan Ji Zhong Liu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope(NVST)of China since 2017,and our aim is to precisely evaluate the real polarimetric accuracy and sensitivity of this polarimetry by using full Stokes spectro-polarimetric observations of the photospheric line Fe I 532.4 *** the work,we briefly describe the salient characteristic of the NVST as a polarimeter in terms of technology and then characterize its instrumental polarization based on the operation in 2017 and *** is verified that the calibration method utilizing the instrumental polarization calibration unit(ICU)is stable and *** calibration accuracy can reach up to 3×10^-*** on the scientific observation of NOAA Active Region 12645 on 2017 April 5,we estimate that the residual cross-talk from Stokes I to Stokes Q,U and V,after the instrumental polarization calibration,is about 4×10^-3 on average,which is consistent with the calibration accuracy and close to the photon *** polarimetric sensitivity(i.e.,the detection limit)for polarized light is of the order of 10-3 with an integration time over 20 *** modulation rate is indeed an issue for the present *** present NVST polarimeter is expected to be integrated with a high-order adaptive optics system and a field scanner to realize 2 D vector magnetic field measurements in the following instrumentation update.

关键词： techniques:polarimetric techniques:spectroscopic Sun:magnetic fields

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Irradiation study of liquid crystal variable retarder for Full-disk Magneto-Graph payload onboard ASO-S mission

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Chinese Physics B 2020年第7期29卷 346-355页

作者： jun-feng hou Hai-feng Wang Gang Wang Yong-Quan Luo Hong-Wei Li Zhen-Long Zhang Dong-Guang Wang Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed by the Chinese Solar Physics Commu*** one of the three payloads of ASO-S,the Full-disc Magneto-Graph(FMG)will measure the photospheric magnetic fields of the entire solar disk with high spatial and temporal resolution,and high magnetic sensitivity,where liquid crystal variable retarder(LCVR)is the key to whether FMG can achieve its scientific *** far,there is no space flight experience for ***,irradiation study for LCVRs becomes more important and urgent in order to make sure their safety and reliability in space *** this paper,γirradiation,proton irradiation,and ultra-violet(UV)irradiation are tested for LCVRs *** optical and chemical properties during irradiation tests are measured and *** optical properties,there is no significant change in those parameters FMG payload concerned except the *** there is no drastic degradation in the retardation versus voltage during irradiations,the amount of retardation variation is much higher than the instrument ***,an in-flight retardation versus voltage should be added in FMG payload,reducing or even avoiding the impact of retardation *** chemical properties,the clearing point and birefringence of the LC materials almost have no change;the ion density dose not change below 60 krad[Si],but begin to increase dramatically above 60 krad[Si].

关键词： solar telescope liquid crystal variable retarder(LCVR) irradiation

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Pegylated interferon α-2b up-regulates specific CD8+ T cells in patients with chronic hepatitis B

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World Journal of Gastroenterology 2010年第48期16卷 6145-6150页

作者： Ji Chen,Yan Wang,Xue-Jie Wu,jun Li,feng-Qin hou,Gui-Qiang Wang,Department of Infectious Diseases,Center for Liver Diseases,Peking University First Hospital,Beijing 100034,China Department of Infectious Diseases Center for Liver Diseases Peking University First Hospital No. 8 Xishiku Street Xicheng District Beijing 10034 China. wanggq@***

AIM:To investigate the effect of pegylated interferon (IFN) α-2b on specific CD8+ T lymphocytes in patients with chronic hepatitis B (CHB). METHODS:Twenty-one patients with CHB were treated with pegylated IFN α-2b. Periphery blood mononuclear cells were isolated from fresh heparinized blood by Ficoll-Hypaque density gradient centrifugation (density:1.077 g/L,Pharmingen) at weeks 0,4,8,12,and 24,respectively. Frequency of circulating hepatitis B virus (HBV) epitope-specific CD8 T cells was detected by flow cytometry. Cytokines were detected by cytometric bead assay. RESULTS:The frequency of circulating HBV core or env-specific CD8 T cells was higher (P < 0.05),the number of HBV core specific CD8 T cells was greater at week 24 (P < 0.05),the level of Th1-type cytokines [interleukin (IL)-12,tumor necrosis factor-α,and IFN-γ] was higher,while that of Th2-type cytokines (IL-4,IL-6,and IL-10) was lower in responders than in nonresponders (P < 0.05) after pegylated IFN α-2b treatment. The IL-6 level was correlated with HBV DNA (r = 0.597,P = 0.04),while the inducible protein-10 (IP-10) level was correlated with serum alanine aminotransferase (ALT) (r = 0.545,P = 0.005). The IP-10 level at week 8 after pegylated IFN α-2b treatment could predict the normalization of ALT in CHB patients (positive predict value = 56%,negative predict value = 92%). CONCLUSION:Pegylated IFN α-2b can enhance the immune response of CHB patients by increasing the frequency of HBV specific CD8+ T cells and regulating the Th1/Th2 cytokines.

关键词： Chronic hepatitis B Pegylated interferon α-2b therapy Immune response Cytokine

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Design of the Full-disk Magneto Graph (FMG) onboard the ASO-S

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Research in Astronomy and Astrophysics 2019年第11期19卷 11-22页

作者： Yuan-Yong Deng Hai-Ying Zhang Jian-feng Yang Fu Li Jia-Ben Lin jun-feng hou Zhen Wu Qian Song Wei Duan Xian-Yong Bai Dong-Guang Wang Juan Lv Wei Ge Jia-Ning Wang Zhao-Ying Zheng Chen-Jie Wang Nan-Ge Wang hou-Kun Ni Yi-Zhong Zeng Yang Zhang Xiao Yang Ying-Zi Sun Zhi-Yong Zhang Xiao-Fan Wang Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The Full-disk Magneto Graph(FMG),a payload onboard the Advanced Space Solar Observatory(ASO-S),will measure the vector magnetic field in the *** instrument consists of a frontwindow filter,a telescope,an LCVR polarimeter,an image-stabilization system,a seven-stage tunable Lyot filter,a CMOS camera with 4096×4096 pixels and a pair of calibration/focus *** this paper,we describe the design of the FMG instrument and provide a summary of test observations carried out with the FMG prototype.

关键词： Sun magnetic fields-space vehicles instruments-methods observational-techniques polarimetric

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High energy diets-induced metabolic and prediabetic painful polyneuropathy in rats

High energy diets-induced metabolic and prediabetic painful ...

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中国神经科学学会第十届全国学术会议

作者： Han FU Fang XIE jun-feng hou Kai JIAO Michael COSTIGAN jun CHEN Institute for Biomedical Sciences of Pain Tangdu HospitalThe Fourth Military Medical University Department of Endocrinology Tangdu HospitalThe Fourth Military Medical University F.M.Kirby Neurobiology Center Children's Hospital Boston

Objective Peripheral neuropathy,with clinical manifestations of pain,sensory,autonomic and even motor dysfunctions,is a major common complication of both diabetes and ***,the link between prediabetes and polyneuropathy is *** establish the role of the metabolic state in the pathogenesis of polyneuropathy,an age- and sex-matched,longitudinal study in rats fed high-fat and high-sucrose diets（HFSD） or high-fat,high-sucrose and high-salt diets（HFSSD） relative to controls was *** Time courses of body weight,systolic blood pressure,fasting plasma glucose（FPG）,insulin,free fatty acids（FFA）,homeostasis model assessment-insulin resistance index（HOMA-IR）,thermal and mechanical sensitivity and motor coordination were measured in ***,large and small myelinated fibers（LMF,SMF） as well as unmyelinated fibers（UMF） in the sciatic nerves and ascending fibers in the spinal dorsal column were quantitatively assessed under electron *** The results showed that early metabolic syndrome（hyperinsulinemia,dyslipidemia,and hypertension） and prediabetic conditions（impaired fasting glucose） could be induced by high energy diet,and these animals later developed painful polyneuropathy characterized by myelin breakdown and LMF loss in both peripheral and central nervous *** contrast SMF and UMF in the sciatic nerves were changed little,in the same *** the phenomenon that high energy diets induce bilateral mechanical,but not thermal,pain hypersensitivity is reflected by severe damage to LMF,but mild damage to SMF and ***,dietary sodium（high-salt） deteriorates the neuropathic pathological process induced by high energy diets,but paradoxically high salt consumption,may reduce,at least temporarily,chronic pain perception in these *** High energy diet can result in prediabetes and metabolic syndrome that cause myelin damage and axonal degeneration in LMF and slight changes in UMF,which may cont

关键词： high energy diets painful neuropathy metabolic syndrome insulin resistance prediabetes neuropathic pain myelin breakdown axonal loss

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独立董事团队异质性对企业内部控制缺陷披露质量的影响

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商业研究 2017年第9期 127-134页

作者：冯均科侯玮马晨西北大学经济管理学院西安710127

规范的独立董事能够有效改善上市公司的治理结构,有助于提升公司内部控制的有效性。基于团队异质性、高层梯队等理论,本文以2007-2015年我国沪深A股上市公司为样本,实证分析独立董事异质性对内部控制缺陷披露质量的影响。结果表明:教育... 详细信息

规范的独立董事能够有效改善上市公司的治理结构,有助于提升公司内部控制的有效性。基于团队异质性、高层梯队等理论,本文以2007-2015年我国沪深A股上市公司为样本,实证分析独立董事异质性对内部控制缺陷披露质量的影响。结果表明:教育以及兼职数异质性对内部控制缺陷披露质量存在显著正相关性,任期异质性、薪酬异质性与内部控制缺陷披露质量具有负相关性,而年龄、性别、专业背景、学术背景与职业背景异质性对其影响不显著。上述结果不仅增强了对内部控制建设重要性的关注,还有利于上市公司从管理者团队特征的角度加强公司独立董事团队的建设,有利于公司治理水平的提升,深层次地拓展了有关于内部控制缺陷披露质量的研究。

关键词：独立董事异质性内部控制缺陷披露质量

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Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin jun Xu Delong Jiang Jiayang hou Ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Lithium-ion battery State-of-health estimation Data-driven Machine learning Ensemble learning Ensemble diversity

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