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The development,performances and applications of the monochromatic X-rays facilities in(0.218–301)keV at NIM,China

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Nuclear Science and Techniques 2021年第6期32卷 108-121页

作者： Si-Ming Guo Jin-jie Wu dong-jie Hou National Institute of Metrology BeijingChina

Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the *** worldwide have launched numerous space exploration *** calibration of the detectors on the ground is a crucial element for space science satellites to obtain observational *** the purpose of providing calibration for various satellite-borne detectors,multiple monochromatic X-rays facilities have been built at the National Institute of Metrology,***(NIM).These facilities mainly pertain to grating diffraction and Bragg diffraction,and the energy range of the produced monochromatic X-rays is 0.218–301 ke *** facilities have a high performance in terms of energy stability,monochromaticity,and flux *** monochromaticity was greater than 3.0%.The energy stability of the facility is 0.02%at 25 ke V over 8 h,and the flux stability was within 1.0%at 25 ke V over 8 *** experiments on the properties of satellite-borne detectors,such as energy linearity,energy resolution,detection efficiency,and temperature response,can be conducted at the *** far,the calibration of two satellites has been completed by the authors,and the work on three other satellites is in *** study will contribute to the advancement of X-ray astronomy the development of Chinese space science.

关键词： Monochromatic X-rays Monochromator Bragg diffraction Energy spectra Calibration

Remaining Useful Life Prediction for a Roller in a Hot Strip Mill Based on Deep Recurrent Neural Networks

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IEEE/CAA Journal of Automatica Sinica 2021年第7期8卷 1345-1354页

作者： Ruihua Jiao Kaixiang Peng jie dong the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083 the AVIC Xi’an Aviation Brake Technology Co. Ltd.Xi’an 710065China the Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Accurate estimation of the remaining useful life(RUL)and health state for rollers is of great significance to hot rolling *** can provide decision support for roller management so as to improve the productivity of the hot rolling *** addition,the RUL prediction for rollers is helpful in transitioning from the current regular maintenance strategy to conditional-based ***,a new method that can extract coarse-grained and fine-grained features from batch data to predict the RUL of the rollers is proposed in this ***,a new deep learning network architecture based on recurrent neural networks that can make full use of the extracted coarsegrained fine-grained features to estimate the heath indicator(HI)is developed,where the HI is able to indicate the health state of the *** that,a state-space model is constructed to describe the HI,and the probabilistic distribution of RUL can be estimated by extrapolating the HI degradation model to a predefined failure ***,application to a hot strip mill is given to verify the effectiveness of the proposed methods using data collected from an industrial site,and the relatively low RMSE and MAE values demonstrate its advantages compared with some other popular deep learning methods.

关键词： Hot strip mill prognostics and health management(PHM) recurrent neural network(RNN) remaining useful life(RUL) roller management.

The texture and its optimization in magnesium alloy

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Journal of Materials Science & Technology 2020年第7期42卷 175-189页

作者： Jialin Wu Li Jin jie dong Fenghua Wang Shuai dong National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong UniversityShanghai 200240China

The crystallographic orientations are generally non-random in wrought Mg alloy,which will lead to their macroscopic physical properties to be *** the texture evolution in processing of Mg alloy billets and its effect on mechanical properties is therefore an important project for all scientists and engineers in material *** paper is concerned with the description of texture,with the mechanisms of texture evolution and with the interrelationships between texture and mechanical properties in Mg *** is a full review of understanding of the basic mechanism on texture evolution,of texture altering by alloying or processing,and of the mechanism of texture ***,it provides theories necessary and available techniques to develop high-performance Mg wrought with optimized texture in the field.

关键词： Magnesium alloy Texture Rare earth(RE) Anisotropic Mechanical property

Modulation instability,rogue waves and conservation laws in higher-order nonlinear Schrodinger equation

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Communications in Theoretical Physics 2021年第2期73卷 1-10页

作者： Min-jie dong Li-Xin Tian School of Mathematical Sciences Nanjing Normal UniversityNanjingJiangsu 210023China Nonlinear Scientific Research Center Jiangsu UniversityZhenjiangJiangsu 212013China

In this paper,the modulation instability(MI),rogue waves(RWs)and conseryation laws of the coupled higher-order nonlinear Schrodinger equation are *** to MI and the 2×2 Lax pair,Darboux-dressing transformation with an asymptotic expansion method,the existence and properties of the one-,second-,and third-order RWs for the higher-order nonlinear Schrodinger equation are *** addition,the main characteristics of these solutions are discussed through some graphics,which are draw widespread attention in a variety of complex systems such as optics,Bose-Einstein condensates,capillary fow,superfluidity,fluid dynamics,and *** addition,infinitely-many conservation laws are established.

关键词： higher-order nonlinear Schrodinger equation modulation instability rogue waves conservation laws

Effects of holding time and Zener-Hollomon parameters on deformation behavior of cast Mg-8Gd-3Y alloy during double-pass hot compression

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Journal of Materials Science & Technology 2018年第11期34卷 2035-2041页

作者： Xi Nie Shuai dong Fenghua Wang Li Jin jie dong National Engineering Research Center of Light Alloy Net Forming School of Material Sciences and EngineeringShanghai Jiao Tong University

Double-pass hot compression tests were carried out over a wide range of holding time（0–180 s） and Zener-Hollomon parameter（1.6 E15–1.3 E20） to study the deformation behavior of cast Mg-8 Gd-3 Y *** flow curves show obvious work hardening and strain softening stages, leading to the peak stress of double-pass hot compression. Holding time and Zener-Hollomon parameter can significantly affect the second pass peak stress. It is found that increasing the holding time can cause a higher peak stress in the second pass deformation. The second pass stress reaches the peak stress of 71 MPa at ZenerHollomom parameter of 1.6 E15. When the parameter rises to 1.3 E20, the second pass peak goes up to237 MPa. In addition, the second pass peak stress is significantly higher than the unloading stress, which is opposite to the flow behavior of aluminum alloys. Residual stored deformation energy caused by the first pass deformation could be consumed by metadynamic recrystallization. Therefore, more strain energy is required for subsequent dynamic recrystallization, resulting in hardening behavior. A hardening fraction is defined to describe the deformation behavior quantitatively, which shows a positive correlation with the metadynamic recrystallization fraction. The metadynamic recrystallization leads to grain growth at the inter pass holding stage, diminishing dynamic recrystallization nucleation positions in the second pass deformation.

关键词： Mg-8Gd-3Y magnesium alloy Double pass hot compression Deformation behavior Metadynamic recrystallization

Future temperature changes over the critical Belt and Road region based on CMIP5 models

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Advances in Climate Change Research 2018年第1期9卷 57-65页

作者： dong Tian-Yun dong Wen-jie GUO Yan CHOU jie-Ming YANG Shi-Li TIAN Di YAN dong-dong State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China School of Atmospheric Sciences Sun Yat-Sen UniversityGuangzhou 510275China Zhuhai Joint Innovative Center for Climate-Environment-Ecosystem Future Earth Research InstituteBeijing Normal UniversityZhuhai 519087China Business School Beijing Normal UniversityBeijing 100875China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyHangzhou310012China

Based on data of 22 models from the Coupled Model Inter-comparison Project Phase 5(CMIP5),the performance of climate simulation is assessed and future changes under RCP2.6,RCP4.5 and RCP8.5 are projected over critical Belt and Road *** with observations,the CMIP5 models simulate the linear trend and spatial distribution of the annual mean surface air temperature(SAT)better in the north(NBR)and south(SBR)of the Belt and Road *** trend of the 22-model ensemble mean(CMIP5 MME)is 0.70/0.50 C per 100 years from 1901 to 2005,and the observed trend is 1.11/0.77 C per 100 years in the NBR/SBR *** 1971,the relative error between CMIP5 MME and observations is 22%/15%in the NBR/SBR ***/nine models are selected in the NBR/SBR to project future SAT changes under three RCP *** 2081e2100,warming in the NBR/SBR is projected to be(1.16±0.29)/(0.72±0.32)C,(2.41±0.54)/(1.55±0.44)C,and(5.23±1.02)/(3.33±0.65)C for RCP2.6,RCP4.5,and RCP8.5,*** the RCP scenarios,the NBR region shows greater warming than the SBR *** most significant warming is expected in Kazakhstan and the northern part of the *** associated uncertainty generally increases with time under the three RCP ***,increases in warming over the Belt and Road region are more remarkable under higher-emission scenarios than lower-emission ones.

关键词： CMIP5 models The Belt and Road region Temperature projection RCPs

Local multi-model integrated soft sensor based on just-in-time learning for mechanical properties of hot strip mill process

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Journal of Iron and Steel Research International 2021年第7期28卷 830-841页

作者： jie dong Ying-ze Tian Kai-xiang Peng Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research Center for Advanced Rolling Technology University of Science and Technology BeijingBeijing 100083China

The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control and optimization of hot rolling *** solve the problem that it is difficult to measure the mechanical properties of hot rolled strip in time and accurately,a soft sensor based on ensemble local modeling was ***,outliers of process data are removed by local outlier *** standardization and transformation,normal data that can be used in the model are ***,in order to avoid redundant variables participating in modeling and reducing performance of models,feature selection was applied combing the mechanism of hot rolling process and mutual information among ***,features of samples were extracted by supervised local preserving projection,and a prediction model was constructed by Gaussian process regression based on just-in-time learning(JITL).Other JITL-based models,such as support vector regression and gradient boosting regression tree models,keep all variables and make up for the lost information during dimension ***,the soft sensor was developed by integrating individual models through stacking *** and reliability of proposed soft sensors were verified by actual process data from a real hot rolling process.

关键词： Soft sensor Just-in-time learning Multi-model Hot rolling

Manufacture of Extra-Thin Wall Steel Pipe by LD Cluster Mill　

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Journal of Iron and Steel Research International 1996年第1期3卷 14-18页

作者： dong jie Central Iron and Steel Research Institute MMI

The manufacture of extra-thin wall steel pipe by LD cluster mill through suitable tool design and process design was described in *** defects in steel pipe produced during rolling were analysed and some measures were taken to improve *** kinds of extra-thin wall steel pipes have been produced successfully,which are as follows:φ18.5mm×0.25 mm,φ15.5mm×0.25 mm,φ11.4mm×0.2mm,φ14- 24mm×0.12 mm,φ21.74mm×0.12 mm.

关键词： rolling extra-thin wall steel pipe LD cluster mill

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Simultaneously improving strength and ductility through laminate structure design in Mg–8.0Gd–3.0Y-0.5Zr alloys

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Journal of Materials Science & Technology 2021年第12期71卷 195-200页

作者： Jing Li Mengjie Zhao Li Jin Fenghua Wang Shuai dong jie dong National Engineering Research Center of Light Alloy Net Forming&State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

The laminate structure was applied to improve the mechanical properties of Mg-8.0 Gd-3.0 Y-0.5 Zr *** types of laminate structures only with different distribution positions of fine grains were produced by friction-stir *** show that the trilayer structure sample exhibits an excellent strengthductility synergy compared to the homogenous structure and bilayer *** enhanced mechanical properties are resulted from the hetero-deformation induced(HDI)stress strengthening and strain hardening which would be enhanced by increasing the quantity of *** observations suggest a crucial role of the number of interfaces in designing the laminate structure.

关键词： Friction-stir processing Mg-Gd-Y-Zr alloy Laminate structure Interface Strength-ductility synergy