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基于1553B总线的大规模信息系统设计问题研究

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载人航天 2024年第3期30卷 364-371页

作者：冯帅牛剑李经松董暘暘于丹王磊蔡彪张锦江北京控制工程研究所北京100190

某大型航天器GNC系统应用1553B总线构建了其规模庞大的信息系统,在信息系统设计过程中产生了3个问题:超长总线下的稳定通信、应用层协议的设计、多条总线的管理等。对这3个问题开展研究,描述了3个问题的由来,给出了问题的解决方法,并验... 详细信息

某大型航天器GNC系统应用1553B总线构建了其规模庞大的信息系统,在信息系统设计过程中产生了3个问题:超长总线下的稳定通信、应用层协议的设计、多条总线的管理等。对这3个问题开展研究,描述了3个问题的由来,给出了问题的解决方法,并验证了方法的实际效果。结果表明:总线中继的方法,有效解决了1553B总线在240 m长度下的稳定可靠通信问题;广播帧计数回传的应用层协议,节省了总线数据通讯开销、并提供了丰富的故障诊断信息;遍历寻优的总线管理策略,最大程度上发挥了多机多总线系统的容错能力。

关键词： 1553B总线信息系统总线中继器应用层协议总线管理 GNC

Effect of Hydrostatic Pressure on LPSO Kinking and Microstructure Evolution of Mg–11Gd–4Y–2Zn–0.5Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 248-264页

作者： Ce Zheng shuai-feng Chen Rui-Xue Wang Shi-Hong Zhang Ming Cheng Institute of Metal Research Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China Department of Materials Science and Engineering and Research Institute of Advanced Materials(RIAM) Seoul National UniversitySeoul 08826Republic of Korea

Two different kinds of hot compressions,namely normal-compression and can-compression,were performed on the Mg–11 Gd–4 Y–2 Zn–0.5 Zr alloy,featured with long period stacking ordered(LPSO)*** kinking behavior of LPSO phase and microstructure evolution was investigated to clarify the effect of levels of imposed hydrostatic *** results suggest that the LPSO phases including both the intragranular 14 H-LPSO phase and intergranular 18 R-LPSO phase suffer severe kinking behavior under higher hydrostatic pressure induced by can-compression,which is firstly characterized with more kinking times and smaller relative kinking *** main reason for such enhanced LPSO kinking during cancompression may be mainly ascribed to the higher dislocation density under a higher level of hydrostatic ***,a competitive relationship between the kink behaviors of intergranular 18 R-LPSO phase and intragranular 14 H-LPSO phase was *** is,the intergranular 18 R-LPSO phase only kinks obviously on the condition that the surrounded intragranular 14 H-LPSO phase scarcely *** contrast to the distinctive kinking of LPSO phase,the dynamic recrystallization(DRX)mechanism shows less dependence on the hydrostatic ***,similar DRX fractions and crystallographic texture were attained for two compression processes owing to the similar operation of deformation mode.

关键词： Magnesium alloy Hydrostatic pressure Long period stacking ordered(LPSO)phase Kinking Dynamic recrystallization

Developments of New Sheet Metal Forming Technology and Theory in China

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1452-1470页

作者： Shi-Hong Zhang shuai-feng Chen Yan Ma Hong-Wu Song Ming Cheng Institute of Metal Research Chinese Academy of Sciences

Developments of new sheet metal forming technology and theory in China are reviewed in detail in this *** of crystal plasticity on the deformation mechanism of Mg alloy are firstly described, especially its applications on the prediction of sheet forming process. Then, a new macroscopic constitutive model is introduced, which possesses an enhanced description capacity of tension/compression anisotropy and anisotropic hardening. In order to take into account the twinning process of hexagonal close-packed material, a modified hierarchical multi-scale model is also established with adequate accuracy in a shorter computational time. The advanced forming limit of sheet metal, mainly about aluminum alloy, is also investigated. Besides the above theory developments, some new sheet metal forming technologies are reviewed simultaneously. The warm forming technology of Mg alloy is discussed. New processes to form sheet parts and to bend tubes are proposed by using hard granules. On the other hand, a new kind of ultra-high-strength steel based on typical22 Mn B5 by introducing more residual austenite and Cu-rich phase to increase the elongation and strength and its novel forming method that integrates hot stamping and quenching participation are proposed. Progresses in sheet hydroforming,press forging and electromagnetic forming of sheet metal parts are also summarized.

关键词： Sheet forming Crystal plasticity Constitutive modeling Mg alloy UHSS Hot stamping Hydroforming Aluminum alloy

Modeling the Dynamic Recrystallization of Mg–11Gd–4Y–2Zn–0.4Zr Alloy Considering Non-uniform Deformation and LPSO Kinking During Hot Compression

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Acta Metallurgica Sinica(English Letters) 2019年第9期32卷 1122-1134页

作者： Hong-Xuan Zhang shuai-feng Chen Ming Cheng Ce Zheng Shi-Hong Zhang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Hot compression tests of Mg–11 Gd–4 Y–2 Zn–0.4 Zr alloy(GWZK114)were conducted at a deformation temperature range of 300–500°C and a strain rate range of 0.01–10.0 *** on systematic microstructure observation,it is confirmed that long period stacking ordered(LPSO)phase displays essential and evolving roles on the dynamic recrystallization(DRX)*** results indicate that the plastic deformation is mainly coordinated by simultaneous exist of LPSO kinking of lamella 14 H-LPSO phase and DRX at 350–450℃,and DRX at 500℃.Further,it is found that the LPSO kinking induced during 350–450℃can delay the DRX.A phenomenological DRX model of GWZK114 alloy is established to be XDRX=***[-0.5((ε-εc)/ε^*)0.91].Non-uniform distribution of plastic strain during compression was considered via finite element method and it ensures a good prediction of DRX fraction under a large plastic ***,an enhanced DRX model,taking its formulation as XDRX={***[-0.5((ε-εc)/ε*)0.91]}(T/(226.8)-1)n,n=3.82ε0.083,is proposed for the first time to capture the hindering effect of 14 H-LPSO kinking on DRX *** predicted results of this enhanced DRX model agree well with the experimental cases,where 14 H-LPSO kinking is dominated or partially involved(300–450℃).Besides,a size model of DRX grains is also established and can depict the evolution of DRX grain size for all the investigated compression conditions with accounting for temperature rising at high strain rates(5 s^-1 and 10 s^-1).

关键词： Mg-11 Gd-4Y-2Zn-0.4Zr alloy Modeling Dynamic recrystallization Non-uniform strain-LPSO kinking

Absolute band gaps of a two-dimensional triangular-lattice dielectric photonic crystal with different shapes

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1788-1792页

作者： feng shuai YANG YuPing LAN ChuWen BAI ZhenZhen WANG YiQuan School of Science Minzu University of ChinaBeijing 100081China

Absolute band gaps of a two-dimensional triangular-lattice photonic crystal are calculated with the finite-difference time-domain method in this *** calculating the photonic band structures of the triangular-lattice photonic crystal consisting of Ge rods immersed in air with different shapes,it is found that a large absolute band gap of 0.098 (2c/a) can be obtained for the structures with hollow triangular Ge rods immersed in air,corresponding to 19.8% of the middle *** influence of the different factors on the width of the absolute band gaps is also discussed.

关键词： photonic crystal absolute band gap triangular lattice

Deformation Mechanism of AZ31B Magnesium Alloy Under Different Loading Paths

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1426-1434页

作者： shuai-feng Chen Li Zheng Shi-Hong Zhang Hong-Wu Song Ming Cheng Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering Shenyang University of Technology

Deformation and texture evolution of AZ31 B magnesium（Mg） alloy sheet under uniaxial tension, compression, and reverse loading after different pre-strain（compression and tension） were investigated experimentally. The results indicate that the pre-compressive strain remarkably affects the reverse tensile yield stress and the width of the detwinning-dominant stage during inverse tension process. Similar to stress–strain curve of the uniaxial compression, the curve of reverse tensile yield value also has ‘S＇ shape, and its minimum value is only 38 MPa. The relationship between pre-compressive strain and the width of detwinning-dominant stage presents a linear growth, and the greater the precompressive strain is, the smaller the strain hardening rate of the detwinning-slip-dominant stage is. Compared with the reverse tension under pre-compression, the influence of the pre-tension deformation on the deformation mechanism of subsequent compression is relatively simple. With the increase in pre-tension strain, the yield stress of the reverse loading is rising.

关键词： AZ31B magnesium alloy Loading path Detwinning Texture Yield stress

A review on theoretical models for lithium-sulfur battery cathodes

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InfoMat 2022年第3期4卷 9-33页

作者： shuai feng Zhong-Heng Fu Xiang Chen Qiang Zhang College of Chemistry and Chemical Engineering Taishan UniversityTaianChina'2Beijing Key Laboratory of Green Chemical Reaction Engineering and TechnologyDepartment of Chemical EngineeringTsinghua UniversityBeijingChina

Lithium–sulfur(Li–S)batteries have been considered as promising battery systems due to their huge advantages on theoretical energy density and rich ***,the shuttle effect and sluggish transformation of soluble lithium polysulfides(LiPSs)hinder the practical application of Li–S *** sulfur host materials with unique catalytic activity have been exploited to inhibit the shuttle effect and accelerate LiPSs redox reactions,in which theoretical simulations have been widely *** review aims to summarize the fundamentals and applications of theoretical models in sulfur ***,the integration of theoretical models provides insights into the adsorption and conversion mechanisms of LiPSs and is further utilized in the smart design of catalysts for the exploitation of practical Li–S ***,a perspective on the future combination of calculation technology and theoretical models is provided.

关键词： DFT calculations electrocatalysts Li-S batteries sulfur cathodes theoretical models

An Efficient Algorithm Based on Spectrum Migration for High Frame Rate Ultrasound Imaging

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Computer Modeling in Engineering & Sciences 2021年第2期126卷 739-754页

作者： shuai feng Liu Jin YadanWang Wei Zhao Hu Peng Heyuan Qiao Department of Biomedical Engineering Hefei University of TechnologyHefei230009China Yijishan Hospital ofWannanMedical College Wuhu241001China

The high frame rate(HFR)imaging technique requires only one emission event for ***,it can achieve ultrafast imaging with frame rates up to the kHz regime,which satisfies the frame rate requirements for imaging moving tissues in scientific research and ***’s Fourier migration method is based on a non-diffraction beam to obtain HFR images and can improve computational speed and ***,in order to obtain high-quality images,Fourier migration needs to make full use of the spectrum of echo signals for imaging,which requires a large number of Fast Fourier Transform(FFT)points and increases the complexity of the hardware when the echo frequency is ***,an efficient algorithm using the spectrum migration technique based on the spectrum’s distribution characteristics is proposed to improve the imaging efficiency in HFR *** the actual echo signal spectrum is of limited bandwidth,low-frequency and high-frequency parts with low-energy have little contribution to the imaging *** transform the effective part that provides the main energy in the signal spectrum to the imaging spectrum while the ineffective spectrum components are not utilized for *** can significantly reduce the number of Fourier transform points,improve Fourier imaging efficiency,and ensure the imaging *** proposed method is evaluated on simulated and experimental *** demonstrated that the proposed method could achieve equivalent image quality with a reduced point number for FFT compared to the complete spectrum *** this paper,it only requires a quarter of the FFT points used in the complete spectrum migration,which can improve the computational efficiency;thus,it is more suitable for real-time data *** proposed spectrum migration method has a specific significance for the study and clinical application of HFR imaging.

关键词： High frame rate imaging spectrum migration Fourier migration

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菊苣酸治疗代谢性疾病药理作用研究进展

中国药事 2024年第7期38卷 821-830页

作者：李俊强崔光志吴超张文丽冯帅李峰山东中医药大学济南250355 烟台市食品药品检验检测中心烟台264000 日照市中医医院日照276800 山东药品食品职业学院威海264210 威海百合生物技术股份有限公司威海264300 山东现代学院济南250355

代谢性疾病是一类由物质或能量代谢异常引起的全身多系统代谢异常的疾病,包括糖尿病、肥胖、非酒精性脂肪性肝病、高脂血症、痛风等。代谢性疾病的病因与遗传、饮食、运动、衰老和环境等众多因素相关,其病程发展缓慢不易察觉且发病后难... 详细信息

代谢性疾病是一类由物质或能量代谢异常引起的全身多系统代谢异常的疾病,包括糖尿病、肥胖、非酒精性脂肪性肝病、高脂血症、痛风等。代谢性疾病的病因与遗传、饮食、运动、衰老和环境等众多因素相关,其病程发展缓慢不易察觉且发病后难以治愈,已经成为全球主要的公共卫生问题。从天然化合物中寻找治疗代谢性疾病的有效药物具有重要意义。菊苣酸为蒲公英、菊苣等多种天然药用植物中的重要活性成分,现代药理学研究表明,菊苣酸在抗炎、抗氧化、平衡糖脂代谢、降尿酸、肝脏保护等方面具有显著的生物活性。本文通过汇总国内、外相关文献,全面综述了菊苣酸在治疗糖尿病、肥胖、非酒精性脂肪性肝病、高脂血症、痛风相关代谢性疾病的研究进展,旨在为菊苣酸治疗代谢性疾病药理作用的深入研究提供参考。

关键词：菊苣酸代谢性疾病药理糖尿病肥胖非酒精性脂肪性肝病高脂血症痛风