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Designing the counter pressure casting gating system for a large thin-walled cabin by machine learning

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China Foundry 2025年

作者： Xiao-long Zhang Hua Hou Xiao-long pei Zhi-qiang Duan Yu-hong zhao School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-performance Al/Mg Alloy Materials North University of China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Institute of Materials Intelligent Technology Liaoning Academy of Materials

The design of casting gating system directly determines the solidification sequence, defect severity,and overall quality of the casting. A novel machine learning strategy was developed to design the counter pressure casting gating system of a large thin-walled cabin casting. A high-quality dataset was established through orthogonal experiments combined with design criteria for the gating system. Spearman's correlation analysis was used to select high-quality features. The gating system dimensions were predicted using a gated recurrent unit(GRU) recurrent neural network and an elastic network model. Using EasyCast and ProCAST casting software, a comparative analysis of the flow field, temperature field, and solidification field can be conducted to demonstrate the achievement of steady filling and top-down sequential solidification. Compared to the empirical formula method, this method eliminates trial-and-error iterations, reduces porosity, reduces casting defect volume from 11.23 cubic centimeters to 2.23 cubic centimeters, eliminates internal casting defects through the incorporation of an internally cooled iron, fulfilling the goal of intelligent gating system design.

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Effect of lanthanum on microstructure of a nickel-based single crystal superalloy

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China Foundry 2025年第1期22卷 55-64页

作者： hong Gao Kai Guan Ren-jie Cui Jian-chao Qin Zi-han zhao zhao-hui Huang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China

To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.

关键词： single crystal superalloy lanthanum microstructure heat-treatment precipitate phase

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从院系视角探讨大学管理模式

清华大学教育研究 2005年第4期26卷 33-38页

作者：王敏裴兆宏清华大学物理系北京100084 清华大学人事处北京100084

本文考察了中国大学现行的管理模式,并通过对大学管理体系中的学术系统和行政系统的分析,探讨了如何在院系层面加强教师参与管理的力度,进而提出以此为基础构建起行政管理与学术管理有机结合的大学管理模式。

关键词：院系视角大学管理模式

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基于广义S变换的时相调制时频聚集性能优化

北京邮电大学学报 2012年第1期35卷 125-128页

作者：迟华山王红星张敏赵培洪海军航空工程学院电子信息工程系山东烟台264001 清华大学电子工程系北京100084

为了提高时相调制(TPM)信号S变换的时频聚集性能,将广义S变换(GST)应用于TPM信号的时频分析中.GST在标准S变换窗函数的基础上,增加了可控参量,利用优化新增参量的算法,优化时频域各频率点处的时窗宽度,从而达到提高时频聚集性能的目的.... 详细信息

为了提高时相调制(TPM)信号S变换的时频聚集性能,将广义S变换(GST)应用于TPM信号的时频分析中.GST在标准S变换窗函数的基础上,增加了可控参量,利用优化新增参量的算法,优化时频域各频率点处的时窗宽度,从而达到提高时频聚集性能的目的.仿真结果表明,广义S变换方法与标准S变换相比,能有效提高TPM信号的时频聚集性能,同时保持了TPM信号用于携带信息相位突变的特性,有利于下一步的信号检测.

关键词： S变换广义S变换时相调制时频分布时频聚集性

Machine learning for online control of particle accelerators

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 94-104页

作者： Xiaolong Chen Zhijun Wang Yuan He hong zhao Chunguang Su Shuhui Liu Weilong Chen Xiaoying zhao Xin Qi Kunxiang Sun Chao Jin Yimeng Chu hongwei zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technonlogy Guangdong Laboratory Huizhou 516000China Department of Physics Xiamen UniversityXiamen 361005China

Particle accelerators play a critical role in modern scientific ***,existing manual beam control methods heavily rely on experienced operators,leading to significant time consumption and potential challenges in managing next-generation accelerators characterized by higher beam current and stronger nonlinear *** this paper,we establish a dynamical foundation for designing the online adaptive controller of accelerators using machine *** provides a guarantee for dynamic controllability for a class of scientific instruments whose dynamics are described by spatial-temporal equations of motion but only part variables along the instruments under steady states are *** necessity of using historical time series of beam diagnostic data is *** strategies involve also employing a well-established virtual beamline of accelerators,by which various beam calibration scenarios that actual accelerators may encounter are *** the reinforcement learning algorithm is adopted to train the controller with the interaction to the virtual ***,the controller is seamlessly transitioned to real ion accelerators,enabling efficient online adaptive control and ***,the controller demonstrates significant robustness,effectively managing beams with diverse charge mass ratios without requiring *** a controller allows us to achieve the global control within the entire superconducting section of the China Accelerator Facility for Superheavy Elements.

关键词： nonlinear complex system adaptive control machine learning particle accelerator simulation to reality

Comparisons of{100}texture improvement and formability in hot-rolled non-oriented electrical steel by austenite-ferrite phase transformation and shear deformation

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Journal of Iron and Steel Research International 2025年第1期32卷 171-185页

作者： Chi-hao Yu hong-jiang Pan Yan-ping zhao De-ting Tang Hai-jun Wang Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093YunnanChina School of Electronics and Information Engineering Anshun UniversityAnshun561000GuizhouChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina

Over the years,the high magnetic induction of industrial Mn-added electrical steel is assumed to be the enhancement of{100}texture derived from its austenite-ferrite phase transformation during hot rolling(phase transformation(PT)method).However,it is still undetermined without straightforward experimental *** reason for{100}texture improvement of Mn-added electrical steel is experimentally confirmed due to the recrystallization induced by the austenite-ferrite phase transformation during hot ***,a more promising methodology to further improve{100}texture and formability of hot-rolled electrical steel is promoted by the control of hot rolling deformation condition(shear deformation(SD)method).The results show that the nucleation mechanisms of{100}oriented recrystallized grains are different in the samples by SD and PT methods,which are in-depth shear deformation and austenite-ferrite phase transformation,*** this case,coarse{100}oriented recrystallized grains and low residual stress are obtained in the sample by SD method,which is responsible for its superior{100}texture and *** contrast,the sample by PT method forms fine recrystallized grains with random orientations and accumulates severe residual stress.

关键词： Non-oriented electrical steel {100}texture Formability Austenite-ferrite phase transformation Shear deformation

Adaptive Control of a Flexible Manipulator With Unknown Hysteresis and Intermittent Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 148-158页

作者： Shouyan Chen Weitian He Zhijia zhao Yun Feng Zhijie Liu Keum-Shik hong School of Mechanical and Electrical Engineering Guangzhou University the School of Control Science and Engineering Shandong University IEEE the College of Electrical and Information Engineering Hunan University the National Engineering Research Center for Robot Visual Perception and Control Technology Hunan University the School of Intelligence Science and Technology University of Science and Technology Beijing (USTB) the Institute for Future the School of AutomationQingdao University the School of Mechanical Engineering Pusan National University

In this study, we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults. First, an inverse hysteresis dynamics model is introduced, and then the control input is divided into an expected input and an error compensator. Second,a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis. Subsequently,by modifying the adaptive laws and local control laws, a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system. Through the direct Lyapunov theory, the proposed scheme allows the state errors to asymptotically converge to a specified interval. Finally,the effectiveness of the proposed scheme is verified through numerical simulations and experiments.

关键词： Adaptive control flexible manipulator intermittent actuator faults inverse hysteresis dynamics vibration control

Curcumin attenuates ochratoxin A and hypoxia co‑induced liver injury in grass carp(Ctenopharyngodon idella)by dual targeting endoplasmic reticulum stress and apoptosis via reducing ROS content

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Journal of Animal Science and Biotechnology 2025年第1期16卷 408-423页

作者： Liangqin Wu Piao zhao pei Wu Weidan Jiang Yang Liu hongmei Ren Xiaowan Jin Xiaoqiu Zhou Lin Feng Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130China Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceChengduSichuan 611130China

Background Ochratoxin A(OTA)is a toxin widely found in aquafeed ingredients,and hypoxia is a common prob-lem in fish *** practice,aquatic animals tend to be more sensitive to hypoxia while feeds are contaminated with OTA,but no studies exist in this *** research investigated the multiple biotoxicities of OTA and hypoxia combined on the liver of grass carp and explored the mitigating effect of curcumin(CUR).Methods A total of 720 healthy juvenile grass carp(11.06±0.05 g)were selected and assigned randomly to 4 experi-mental groups:control group(without OTA and CUR),1.2 mg/kg OTA group,400 mg/kg CUR group,and 1.2 mg/kg OTA+400 mg/kg CUR group with three replicates each for 60 ***,32 fish were selected,divided into nor-moxia(18 fish)and hypoxia(18 fish)groups,and subjected to hypoxia stress for 96 *** CUR can attenuate histopathological damage caused by coming to OTA and hypoxia by reducing vacu-olation and nuclear *** alleviation of this damage was associated with the attenuation of apoptosis in the mitochondrial pathway by decreasing the expression of the pro-apoptotic proteins Caspase 3,8,9,Bax,and Apaf1 while increasing the expression of the anti-apoptotic protein Bcl-2,and attenuation of endoplasmic reticulum stress(ERS)by reducing Grp78 expression and chop *** may be attributed to the fact that the addi-tion of CUR increased the levels of catalase(CAT)and glutathione reductase(GSH),increased antioxidant capacity,and ensured the proper functioning of respiratory chain complexes I and II,which in turn reduced the high produc-tion of reactive oxygen species(ROS),thus alleviating apoptosis and *** In conclusion,our data demonstrate the effectiveness of CUR in attenuating liver injury caused by the combination of OTA and *** study confirms the feasibility and efficacy of adding natural products to mitigate toxic damage to aquatic animals.

关键词： Apoptosis Curcumin Endoplasmic reticulum stress Grass carp Hypoxia Ochratoxin A Oxidative damage

马銮湾养殖区生物体重金属含量特征与安全性评价

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海洋环境科学 2014年第6期33卷 830-836页

作者：王灶生赵佩红颜昌宙中国科学院城市环境研究所城市环境与健康重点实验室福建厦门362021

调查测定了马銮湾养殖区海水、不同生物体重金属含量,阐述了水域污染水平并着重分析了贝类、虾类、蟹类和鱼类体内重金属富集特征,同时根据有关标准中重金属元素的限量值,对海洋生物体内的重金属污染程度进行单因子评价。结果表明:马銮... 详细信息

调查测定了马銮湾养殖区海水、不同生物体重金属含量,阐述了水域污染水平并着重分析了贝类、虾类、蟹类和鱼类体内重金属富集特征,同时根据有关标准中重金属元素的限量值,对海洋生物体内的重金属污染程度进行单因子评价。结果表明:马銮湾水体受到一定程度的重金属污染;彩虹明樱蛤(Moerella iridescens Benson)对Se具有很高的富集性,与水体中的Cu、Ni与Cr含量分别具有极显著(p<0.01)与显著(p<0.05)的正相关关系,可潜在的作为Cu、Ni与Cr污染的良好指示生物;贝类、虾类和蟹类等杂食性甲壳类生物体重金属的含量明显高于鱼类;目前马銮湾被调查的生物体中Cu,Cd和Pb的含量均未超标准,但Se和部分生物体内的Zn,Cr则超过了限量标准。

关键词：重金属富集特征污染指示安全性评价马銮湾