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Prediction of the Charpy V-notch impact energy of low carbon steel using a shallow neural network and deep learning

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1309-1320页

作者： Si-wei Wu jian Yang guang-ming Cao State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

The impact energy prediction model of low carbon steel was investigated based on industrial data. A three-layer neural network, extreme learning machine, and deep neural network were compared with different activation functions, structure parameters, and training functions. Bayesian optimization was used to determine the optimal hyper-parameters of the deep neural network. The model with the best performance was applied to investigate the importance of process parameter variables on the impact energy of low carbon steel. The results show that the deep neural network obtains better prediction results than those of a shallow neural network because of the multiple hidden layers improving the learning ability of the model. Among the models, the Bayesian optimization deep neural network achieves the highest correlation coefficient of 0.9536, the lowest mean absolute relative error of 0.0843, and the lowest root mean square error of 17.34 J for predicting the impact energy of low carbon steel. Among the variables, the main factors affecting the impact energy of low carbon steel with a final thickness of7.5 mm are the thickness of the original slab, the thickness of intermediate slab, and the rough rolling exit temperature from the specific hot rolling production line.

关键词： prediction shallow neural network deep neural network impact energy low carbon steel

Suppression of Rayleigh-Taylor instability by gyroviscosity and sheared axial flow in imploding plasma pinches

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核聚变与等离子体物理 2007年第2期27卷 87-94页

作者： HUANG Lin jian guang-de QIU Xiao-ming Southwestern In stitute of Physics Chengdu 610041

The synergistic stabilizing effect of gyroviscosity and sheared axial flow on the Rayleigh-Taylor instability in Z-pinch implosions is studied by means of the incompressible viscid magneto-hydrodynamic *** gyroviscosity(or finite Larmor radius) effects are introduced in the momentum equation through an anisotropic ion stress *** relation with the effect of a density discontinuity is *** results indicate that the short-wavelength modes of the Rayleigh-Taylor instability are easily stabilized by the gyroviscosity *** long wavelength modes are stabilized by the sufficient sheared axial ***,the synergistic effects of the finite Larmor radius and sheared axial flow can heavily mitigate the Rayleigh-Taylor *** synergistic effect can compress the Rayleigh-Taylor instability to a narrow wave number *** with a sufficient gyroviscosity and large enough flow velocity,the synergistic effect can completely suppressed the Rayleigh-Taylor instability in whole wave number region.

关键词：雷利-泰勒不稳定性回转粘性内向爆炸等离子体箍缩增敏作用有限拉莫尔旋进半径增长比率

Design and analysis of a scheme for the naval gun test shell entering the bore

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Defence Technology（防务技术） 2021年第4期17卷 1374-1386页

作者： Xin-yun Liu Da-lin Wu jian hou Shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China Naval University of Engineering Wuhan430000China

The test shell without projectile belt is widely used in the teaching,inspection and maintenance of modern automatic naval *** order to ensure the normal work of each mechanism,it is very important to design the buffer and limit of the test shell during the process of entering the *** a certain type of medium caliber naval gun as the research object,the design of colloidal fluid damper and cartridge lock was proposed to ensure the reliability of entering the bore and closing the *** combining the simulation methods of computational fluid dynamics(CFD)and multibody system dynamic(MBD),it was analyzed whether the structural design can meet the engineering *** research results show that the colloidal fluid damper can dissipate a large amount of kinetic energy of the shell,and the cartridge lock can limit the rebound *** combination of the two ensures the smooth process of closing the *** research provides a design method for the process of the test shell entering the bore,and provides theoretical support for the feasibility of the method.

关键词： Naval gun Colloidal fluid damper Cartridge lock CFD MBD

Deep reinforcement learning for optimal denial-of-service attacks scheduling

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Science China(Information Sciences) 2022年第6期65卷 98-106页

作者： Fangyuan hou jian SUN Qiuling YANG Zhonghua PANG State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of Technology

We consider an optimal denial-of-service(DoS) attack scheduling problem of N independent linear time-invariant processes, where sensors have limited computational capability. Sensors transmit measurements to the remote estimator via a communication channel that is exposed to DoS attackers. However,due to limited energy, an attacker can only attack a subset of sensors at each time step. To maximally degrade the estimation performance, a DoS attacker needs to determine which sensors to attack at each time step. In this context, a deep reinforcement learning(DRL) algorithm, which combines Q-learning with a deep neural network, is introduced to solve the Markov decision process(MDP). The DoS attack scheduling optimization problem is formulated as an MDP that is solved by the DRL algorithm. A numerical example is provided to illustrate the efficiency of the optimal DoS attack scheduling scheme using the DRL algorithm.

关键词： optimal denial-of-service attack scheduling optimization limited energy deep reinforcement learning

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优化HS-SPME-GC-MS方法表征香菇不同成熟阶段的关键挥发性化合物

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食品科学 2025年第1期46卷 74-82页

作者：侯振山许贺然夏榕嵘李昀婷王娅飞潘松辛广沈阳农业大学食品学院辽宁沈阳110866

通过优化的顶空固相微萃取结合气相色谱-质谱联用技术鉴定香菇不同成熟阶段挥发性化合物,并采用气味活性值(odor activity value,OAV)和偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)进行分析。结果表明:最... 详细信息

通过优化的顶空固相微萃取结合气相色谱-质谱联用技术鉴定香菇不同成熟阶段挥发性化合物,并采用气味活性值(odor activity value,OAV)和偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)进行分析。结果表明:最佳提取条件为1.0 g香菇样品在50℃提取25 min,解吸3 min;在香菇不同成熟阶段共鉴定出71种挥发性化合物,不同成熟阶段挥发性化合物种类和含量存在显著差异(P1和OAV≥1,是香菇不同成熟阶段最重要的差异挥发性化合物。本研究为探究香菇成熟过程中香气形成机制提供一定理论依据。

关键词：香菇成熟阶段香气挥发性化合物顶空固相微萃取气相色谱-质谱偏最小二乘判别分析

Initial Processes of Hydrogen Adsorption on Si（100） Surface

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Communications in Theoretical Physics 2004年第5X期42卷 795-797页

作者： MALi WANGjian-guang WEIShu-Yi WANGguang-hou NationalLaboratoryofSolidStateMicrostructuresandDepartmentofPhysics NanjingUniversityNanjing210093China CollegeofPhysics&InformationEngineer HenanNormalUniversityXinxiang453002China

The adsorption of one monolayer H atoms on an ideal Si(100) surface is studied by using the self-consistent tight binding linear muffin-tin orbital method. Energies of adsorption systems of H atoms on different sites are *** is found that the adsorbed H atoms are more favorable on B1 site (bridge site) with a distance 0.056 nm above the Si surface. There does not exist reaction barrier at the Si surface. The layer projected density states are calculated and compared with those of the clean surface. The charge transfers are also investigated.

关键词：氢硅化学吸收作用半导体电学性质

Electrochemical behavior of Mg-Al-Zn-Ga-In alloy as the anode for seawater-activated battery

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Journal of Materials Science & Technology 2020年第6期41卷 33-42页

作者： Jiarun Li Zhuoyuan Chen jiangping Jing jian hou Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of Sciences7 Nanhai RoadQingdao266071China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteWenhai RoadQingdao266237China Center for Ocean Mega-Science Chinese Academy of Sciences7 Nanhai RoadQingdao266071China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)No.1 Wenhai RoadQingdao266237China

The effect of indium alloying on the corrosion and discharge behaviors of Mg-Al-Zn-Ga alloys is investigated via materials characterization,immersion test and electrochemical *** results indicate that indium alloying can effectively modify the distribution of intermetallic phases in Mg matrix via promoting the segregation of Al in the form of Mg17Al12 in *** addition of indium can effectively activate Mg-Al-Zn-Ga alloy evidenced by increased hydrogen evolution volume and weight loss,negative shift of corrosion and discharge potentials,increase of corrosion current density,decrease of polarization resistance and promoted Faradic ***,excessive indium alloying(2.0 wt.%)would strikingly deteriorate the electrochemical performance of Mg-Al-Zn-Ga anode due to the exorbitant active *** Mg-6 wt.%Al-3 wt.%Zn-1 wt.%Ga-1 wt.%In in as-cast state with acceptable corrosion rate and desirable discharge performance is a low cost,non-toxic and well-performance magnesium alloy,which is a promising anode materials for seawater-activated batteries.

关键词： Magnesium alloy Corrosion Electrochemical behavior Anode Seawater-activated battery

Current research on electrospinning of silk fibroin and its blends with natural and synthetic biodegradable polymers

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Frontiers of Materials Science 2013年第2期7卷 129-142页

作者： jian-guang ZHANG Xiu-Mei MO Biomaterials and Tissue Engineering Lab College of Chemistry Chemical Engineering & Biotechnology Donghua University Shanghai 201620 China

Silk fibroin （SF） is a kind of natural polymers with a great potential in biomedical application. Due to its good biocompatibility, biodegradability and minimal inflammatory reaction, SF is an excellent candidate for generating tissue engineering scaffolds. Electrospinning is a simple and effective method to fabricate nanofibers, which has several amazing characteristics such as very large surface area to volume ratio, flexibility in surface functionalities, and superior mechanical performance. The electro- spun nanofibers from SF and its blends have been used for varied tissue engineering. This paper will give a brief review about the structure, properties and applications of SF and blend nanofibers via electrospinning.

关键词： electrospinning nanofiber silk fibroin (SF) biodegradable polymer

Isometric Extension Problem Between Strictly Convex Two-dimensional Normed Spaces

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Acta Mathematica Sinica,English Series 2019年第4期35卷 513-518页

作者： guang Gui DING jian Ze LI School of Mathematical Sciences and LPMC Nankai University Electrical and Computer Engineering Ryerson University

In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimens... 详细信息

关键词： Isometric extension strictly convex unit sphere smooth point additive map