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Applying of Switch Strong Tracking UKF in Spacecraft Autonomous Celestial Navigation

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Journal of Harbin Institute of Technology(New Series) 2015年第1期22卷 79-84页

作者： Jingjing Li Huayi Li yingchun zhang Shandong Aerospace Electro-Technology Institute Research Center of Satellite Technology Harbin Institute of Technology

Star & Horizon sensor based autonomous navigation methods play an increasingly important role in spacecraft celestial navigation. However,the measurements of star sensors and horizon sensor are frequently affected by uncertain noises from space environment. To improve the estimation precision,a state estimation algorithm named Switch Strong Tracking Unscented Kalman Filter( SSTUKF) is presented. Firstly,the adaptive fading factor is deduced through the adoption of unknown instrumental diagonal matrixes to real time rectify the measurement covariance matrix. Secondly,according to the deduction of Chebyshev law of large numbers,innovation criterion is introduced during estimation to decrease the unnecessary calculation. Finally,SSTUKF is suggested through the adoption of adaptive fading factor and innovation criterion. The filter can switch between the normal filter mode and adaptive filter mode. As the calculation of innovation criterion is less than the adaptive fading factor,SSTUKF improves the estimation efficiency. To demonstrate the effectiveness,SSTUKF is applied to Star & Horizon sensor based autonomous navigation system with uncertain measurement noises. The simulation results verify the proposed algorithm.

关键词： autonomous navigation adaptive filter unscented tr

Space time clock:An on-chip clock with 10^(-12) instability

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Chinese Journal of Aeronautics 2022年第10期35卷 247-253页

作者： Zhendong XU yingchun zhang Pengfei LI Yongsheng WANG Limin DONG Guodong XU School of Astronautics Harbin Institute of TechnologyHarbin 150001China

High precision and stable clock is extremely important in communication and *** miniaturization of the clocks is considered to be the trend to satisfy the demand for5G and the next generation *** on the concept of meter bar and the principle of the constancy of light velocity,we designed a micro clock,Space Time Clock(STC),with the size smaller than 1 mm×1 mm and the power dissipation less than 2 m *** in integrated circuit of 0.18μm technology,the instability of STC is assessed to be 2.23×10^(-12)and the trend of the instability is reversely proportional toτ.With the potential ability to reach the level of 10instability on chip in the future,the period of the STC’s signal is locked on the delay time defined by the meter bar which keeps the time reference *** of its superior performance,the STC is more suitable for mobile communication,PNT(Positioning,Navigation and Timing),embedded processor and deep space application,and becomes the main payload of the ASRTU satellite scheduled to launch next year and investigate in space environment.

关键词： Communication Embedded processor Instability Positioning navigation and timing Space time clock

Nd^(3)+:YAG-Al_(2)O_(3) nanocrystalline transparent ceramics with high inflexion concentration quenching of Nd^(3+) prepared by amorphous crystallization

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Journal of Advanced Ceramics 2024年第8期13卷 1242-1253页

作者： Xiujuan Wan Guangfan Tan Liang Cai Jie Fu Jianqiang Li yingchun zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100080China State Key Lab for Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Rare earth ion-doped Y_(3)Al_(5)O_(12)(YAG)-based transparent ceramics have been used as important laser gain media for a long time,yet the doping concentration of active ions is limited due to concentration quenching,wherein the inflexion concentration quenching of Nd^(3+)is recognized as 1.0 at%.In this work,YAG-Al_(2)O_(3) nanocrystalline transparent ceramics with a concentration of Nd^(3+)(O-5.0 at%)were fabricated via amorphous crystallization,and the crystal structure evolution,morphology,and optical properties were systematically investigated by differential scanning calorimetry(DSC),X-ray powder diffraction(XRD),transmission electron microscopy(TEM),magnetic resonation(MAS),nuclear magnetic resonation(NMR),and fluorescence *** doping of Nd^(3+)can promote the transition of Al[5]and Al[6]to Al[14],indicating improvements in the ability of the amorphous material to form Nd^(3+):Y_(2)O_(3)-Al_(2)O_(3) vitrified beads,and 1.5 at%Nd^(3+):YAG-Al_(2)O_(3) nanocrystalline transparent ceramics can be obtained by crystallization at 1050℃ with a matrix composed of YAG and concomitant δ-Al_(2)O_(3) and θ-Al_(2)O_(3).The nanocrystalline transparent ceramics show an internal transmitance of 89.56%at 1064 nm,and the strongest emission peak corresponds to the energy transfer from 4F_(3/2) to 4l_(11/2) of Nd^(3+)with a fluorescence lifetime of 231μs when pumped by an 808 nm ***,spectral broadening begins to occur,indicating the onset of concentration quenching,when the concentration of Nd^(3+)exceeds 1.5 at%,substantially higher than the 1.0 at% observed in YAG ***-Al_(2)O_(3) nanocrystalline transparent ceramics obtained by amorphous crystalization can be utilized as the matrix to increase the inflexion point of doping concentration quenching of Nd^(3+),and this material may have great potential as a laser gain medium.

关键词： Y_(3)Al_(5)O_(12)(YAG)-Al_(2)O_(3) nanocrystalline transparent ceramics laser gain medium Nd^(3+)

Influencing factors and mechanism of iodine-induced stress corrosion cracking of zirconium alloy cladding:A review

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 586-598页

作者： Yusha Li Changchun Ge Yanhong Liu Guangbin Li Xiaoxu Dong Zongxing Gu yingchun zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Power Investment Corporation Science and Technology Research Institute Beijing 100029China

Failure of the zirconium alloy claddings due to iodine-induced stress corrosion cracking(I-SCC)will increase the risk of fission product *** progress of I-SCC has been comprehensively investigated in a massive amount of published *** a comprehensive understanding of I-SCC,this review focuses on summarizing the mechanisms and influencing factors of *** show that micropits are formed on the surface of zirconium alloys due to the reaction between iodine and zirconium,and then small pits gradually gather to form pit *** are easily generated in pit clusters and propagate along the grain *** reaching a particular condition,the crack will transform into transgranular direction *** the crack develops,it finally becomes a ductile *** also summarize various factors that may affect *** specific cracking conditions are linked to elements,such as iodine concentration,temperature,microstructure,and alloying ***,the improvement of the I-SCC resistance of zirconium alloys needs to be further *** attention can be paid to material properties,such as alloying elements,microstructure,and surface treatment,to improve the I-SCC resistance of zirconium alloys.

关键词： iodine-induced stress corrosion cracking zirconium fracture

Numerical simulation of a UAV impacting engine fan blades

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Chinese Journal of Aeronautics 2021年第10期34卷 177-190页

作者： Jingyu YU Bingjin LI Jun LIU Naidan HOU yingchun zhang Yafeng WANG Yulong LI School of Aeronautics Northwestern Poly technical UniversityXi'an 710072China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China Shanghai Aircraft Airworthiness Certification Center of CAAC Shanghai 200335China China Aircraft Strength Research Institute Xi'an 710065China

A 3D digital model of a small Unmanned Aerial Vehicle(UAV)is obtained by using the method of scanning reverse modeling and joint mapping.A numerical simulation of a small UAV strikes on rotary engine blades,presented in this paper,was performed with a Transient Nonlinear Finite Element code PAM-CRASH software.A test of motor strike on plate was developed and the dynamic response of the plate were obtained to validate the numerical simulation method of a UAV strike on *** on this,dynamic damage response caused by UAV on the engine blades were *** is indicated that the impact process between the UAV and a single blade can be divided into two typical stages:cutting and *** mainly leads to the failure of the leading edge material,and impact mainly leads to the plastic deformation of the *** the same time,it is compared with the damage impacted by bird with the same *** the same mass of bird and UAV,the damage caused by UAV striking fan blade is more serious,and 1.345 kg UAV striking fan blade of typical civil aviation engine is enough to cause damage to flight safety.

关键词： Airworthiness Bird impact Engine fan blade Explicit dynamics UAV

Therapeutic potential and mechanism of functional oligosaccharides in inflammatory bowel disease: a review

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Food Science and Human Wellness 2023年第6期12卷 2135-2150页

作者： Xiaochun Yang Deyong Zeng Chongyang Li Wenchen Yu Guilin Xie yingchun zhang Weihong Lu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China Sichuan Gongda Southwest Food Research Co. Ltd.Bazhong 636063China The Intelligent Equipment Research Center for the Exploitation of Characteristic Food&Medicine Resources Chongqing Research Institute of Harbin Institute of TechnologyChongqing 401135China

Inflammatory bowel disease(IBD)is characterized by recurrent attacks and long courses,and the number of patients has expanded rapidly year by ***,current conventional strategies exist serious adverse *** this case,it is an urgent issue to find out an effective and safe *** oligosaccharides possess safe and excellent physiological activities,and have attracted enormous attention due to their great therapeutic potential for *** review emphasizes the attenuating effects of distinct functional oligosaccharides on IBD and their structure,and summarizes the main mechanisms from the aspects of regulating intestinal fl ora structure,repairing intestinal barrier,modulating immune function and mediating related signaling pathways in order to reveal the relationship between functional oligosaccharides,immune regulation,intestinal epithelial cells,gut fl ora and IBD *** possess excellent protective effects on IBD,and can be considered as safe and functional ingredients in the health food and pharmaceutical industry.

关键词： Oligosaccharides Colitis Pathogenesis Signaling pathway Action mechanism

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Effects of Space Flight on Expression of Key Proteins in Rice Leaves

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Rice science 2020年第5期27卷 423-433,I0026-I0033页

作者： Zeng Deyong Cui Jie Yin Yishu zhang Meng Shan Shan Gao Xin zhang yingchun Sun Yeqing Lu Weihong School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150000China National and Local Joint Engineering Laboratory For Synthesis Transformation and Separation of Extreme Environmental NutrientsHarbin 150001China Dalian Maritime University Institute of Environmental Systems BiologyDalian 116026China

As a unique form of abiotic stress, the environmental conditions of outer space are expected to induce changes in plant genomes, proteomes and metabolic pathways. However, the effect of outer space conditions on the overall physiology of plants at the protein level has yet to be reported. To investigate the effects of outer space conditions on the growth-and development-related physiological processes and metabolic pathways of rice different stages, the seeds of rice variety DN423 were sent into orbit for 12.5 d aboard the SJ-10 Returning Satellite, and then the seedlings of both treated and control rice were compared at the three-leaf stage(TLS) and tillering stage(TS). In addition to comparing plant growth and reactive oxygen species(ROS) levels, seedling proteomes were also compared using isobaric tags for relative and absolute quantitation(i TRAQ). Space flight increased TLS plant height by 20%, reduced and increased ROS levels of the TLS and TS seedlings, respectively, and affected the expression of 36 and 323 proteins in TLS and TS leaves, respectively. Furthermore, the functions of the differentially abundant proteins were mainly associated with metabolism, energy, and protein synthesis and degradation. These results suggested that the exposure of seeds to outer space conditions affects the subsequent abundance of key signaling proteins, gene expression, and the processes of protein synthesis and degradation, thereby affecting metabolic processes and promoting adaptation to the abiotic stress of outer space. As such, the present study sheds light on the effects of space flight on plants and contributes to a more comprehensive understanding of extraterrestrial biology.

关键词： differentially abundant protein rice proteomics space flight isobaric tags for relative and absolute quantitation

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张迎春运用当归芍药散治疗妊娠疾病经验撷菁

湖北中医杂志 2022年第7期44卷 17-20页

作者：甘雨娟张迎春(指导) 湖北中医药大学湖北武汉430065 湖北省妇幼保健院湖北武汉430070

张迎春教授为第六批全国老中医药专家学术经验继承工作指导老师,湖北中医名师,从事中医妇儿临床工作30余年,擅长应用中西医结合以及中医内外兼治法治疗妇科及妊娠相关疾病。当归芍药散起源于东汉末代著名医家张仲景所著《金匮要略》,起... 详细信息

张迎春教授为第六批全国老中医药专家学术经验继承工作指导老师,湖北中医名师,从事中医妇儿临床工作30余年,擅长应用中西医结合以及中医内外兼治法治疗妇科及妊娠相关疾病。当归芍药散起源于东汉末代著名医家张仲景所著《金匮要略》,起初被用于治疗肝郁脾虚型妊娠腹痛,根据异病同治的原则.

关键词：当归芍药散异病同治妊娠疾病临床经验

CHANGES OF HUMAN PERIPHERAL BLOOD LYMPHOCYTE SUBPOPULATIONS FOLLOWING LOW DOSE X-IRRADIATION IN VITRO

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吉林大学学报(医学版) 1993年第2期 109-114页

作者： Liu Shuzheng, Qi Jin, zhang yingchun (MPH Radiobiology Research Unit, PRO

Human peripheral blood lymphocyte subpopulations were identified by immunofluorescence withlabelled monoclonal antibodies against surface antigens (CD3/CD19, CD3/CD16/CD56 and CD4/CD8) and T, B, NK and T subsets were scored by flow cytometry on a FACScan. Blood samples were irradiated with 25-250 mGy X-rays and cultured for 72 hours in RPMI 1640 medium supplemented with fetal calf serum. It was found that the percentage of total and helper T cells as well as the helper to suppressor T ratio increased with time at the expense of B and NK cells while the suppressor T subset was kept around the normal level. The general pattern of the change with time in culture was not significantly influenced by low dose radiation within 0. 1 Gy. There was no prcferntial deletion of the suppressor T subset with the doses used in the present study. Combining previous data with similar observations on the T subsets in immune organs and peripheral blood in mice after low dose whole-body irradiation, the authors emphasized t

关键词： Low nose radiation Human lymphocyte subpopulations T subsets Flow cytometry Surface antigens