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Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： Xing-yuan Miao Hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

优质油菜大地95在西藏主要农区的适应性分析

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作物杂志 2023年第2期 51-56页

作者：赵彩霞袁玉婷西藏自治区农牧科学院农业研究所西藏拉萨850032

为研究优质油菜大地95在西藏主要农区的适应性,在拉萨、堆龙、墨竹、贡嘎、扎囊、白朗、拉孜、昌都、林芝、阿里等10个县市进行试验示范,研究其农艺性状和产量,并分析了经济效益。结果表明,大地95在西藏海拔3100~4000m农区种植可以正常... 详细信息

为研究优质油菜大地95在西藏主要农区的适应性,在拉萨、堆龙、墨竹、贡嘎、扎囊、白朗、拉孜、昌都、林芝、阿里等10个县市进行试验示范,研究其农艺性状和产量,并分析了经济效益。结果表明,大地95在西藏海拔3100~4000m农区种植可以正常成熟,2014-2020年在西藏10个示范点农艺性状差异较大,总产量为1475.51t,总经济效益为1180.40万元,比对照品种增效明显。总之,大地95适宜西藏主要农区生态条件,其推广应用将提高农民的种植效益,促进西藏优质油菜产业的稳定发展。

关键词：油菜大地95 适应性经济效益

A FINITE DIFFERENCE METHOD FOR TWO DIMENSIONAL ELLIPTIC INTERFACE PROBLEMS WITH IMPERFECT CONTACT

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Journal of Computational Mathematics 2024年第5期42卷 1328-1355页

作者： Fujun Cao Dongfang yuan Dongxu Jia Guangwei yuan School of Science Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina School of Science Tianjin University of TechnologyTianjin 300384China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsP.O.Box 8009Beijing 100088China

In this paper two dimensional elliptic interface problem with imperfect contact is considered,which is featured by the implicit jump condition imposed on the imperfect contact interface,and the jumping quantity of the unknown is related to the flux across the interface.A finite difference method is constructed for the 2D elliptic interface problems with straight and curve interface ***,the stability and convergence analysis are given for the constructed ***,in particular case,it is proved to be *** examples for elliptic interface problems with straight and curve interface shapes are tested to verify the performance of the *** numerical results demonstrate that it obtains approximately second-order accuracy for elliptic interface equations with implicit jump condition.

关键词： Finite difference method Elliptic interface problem Imperfect contact

定向凝固Al-Ni-Y三元共晶合金的相组成与凝固特征

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中国稀土学报 2010年第4期28卷 448-453页

作者：王晓书苑玉婷张静徐瑞燕山大学材料科学与工程学院亚稳材料制备技术与科学国家重点实验室河北秦皇岛066004

在5 ***-1温度梯度下,选用1,5,10 ***-1三种拉速率对成分为96.0%Al,1.0%Ni,3.0%Y的三元共晶合金进行定向凝固实验,研究下拉速率对合金组织演化的影响规律。通过X射线衍射和光学显微镜分析表明合金由α-Al相、Al3Y相、Al23Ni6Y4相三相组... 详细信息

在5 ***-1温度梯度下,选用1,5,10 ***-1三种拉速率对成分为96.0%Al,1.0%Ni,3.0%Y的三元共晶合金进行定向凝固实验,研究下拉速率对合金组织演化的影响规律。通过X射线衍射和光学显微镜分析表明合金由α-Al相、Al3Y相、Al23Ni6Y4相三相组成。当下拉速率为1 ***-1时,合金组织呈现三相共晶结构,纵截面有定向凝固趋势;下拉速率为5和10 ***-1时,合金组织演变成两种二相共晶:一种是Al3Y相与α-Al相形成菊花状的不规则二相共晶组织,另一种是Al23Ni6Y4相与α-Al相形成层片状的规则二相共晶组织,纵截面上均有明显的定向凝固特征。

关键词：定向凝固下拉速度三相共晶稀土

Global Spherically Symmetric Solutions for a Coupled Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： Chang Ming SONG Jian Lin ZHANG yuan yuan WANG Department of Applied Mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-Cahn equation spherically symmetry

Motor cortical circuit adaptations in parkinsonism

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Neural Regeneration Research 2024年第10期19卷 2107-2108页

作者： Hong-yuan Chu Department of Neurodegenerative Science Van Andel Research InstituteGrand RapidsMIUSA Aligning Science Across Parkinson’s(ASAP)Collaborative Research Network

Parkinson's disease is a chronic and progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta,which leads to the featured motor impairment of parki... 详细信息

关键词： parkin impairment rigidity

A modified stochastic model for LS+AR hybrid method and its application in polar motion short-term prediction

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Geodesy and Geodynamics 2024年第1期15卷 100-105页

作者： Fei Ye Yunbin yuan State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China BeiDou High-precision Satellite Navigation and Location Service Hunan Engineering Research Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China Hunan Continuously Operating Reference Stations(HNCORS)Data Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame ***,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM ***,the weighted LS+AR hybrid method performs well for PM short-term ***,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR *** this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid *** using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid *** to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,***,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.

关键词： Stochastic model LS+AR Short-term prediction The earth rotation parameter(ERP) Observation model

MOF glass foam: a blueprint to porous membrane scaling-up

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Science China Chemistry 2024年第3期67卷 746-748页

作者： yuan Peng Weishen Yang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

In comparison with conventional energy-intensive separation technologies, such as distillation and crystallization,membrane separation is labelled as an advanced technology with low energy consumption, a small carbon footprint,continuous operation, etc. Metal-organic frameworks(MOFs) are a burgeoning category of crystalline materials consisting of metal ions/clusters coordinated with organic ligands.

关键词： separation porous distillation

Gate Tunable Labyrinth Domain Structures in a van der Waals Itinerant Ferromagnet Cr_(7)Te_(8)

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Chinese Physics Letters 2024年第9期41卷 122-132页

作者： Kui Meng Zeya Li Yicheng Shen Xiangyu Bi Junhao Rao yuting Qian Zhansheng Gao Peng Chen Caiyu Qiu Feng Qin Jinxiong Wu Feng Luo Junwei Huang Hongtao yuan National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210000China Center for the Physics of Low-Dimensional Materials Henan Joint International Research Laboratory of New Energy Materials and DevicesSchool of Physics and ElectronicsHenan UniversityKaifeng 475004China Tianjin Key Lab for Rare Earth Materials and Applications Center for Rare Earth and Inorganic Functional MaterialsSmart Sensor Interdisciplinary Science CenterSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China

Manipulating magnetic domain structure plays a key role in advanced spintronics *** rationale is that the labyrinthine domain structure,normally appearing in ferromagnetic thin films with strong magnetic anisotropy,shows a great potential to increase data storage density for designing magnetic nonvolatile memory and logic ***,an electrical control of labyrinthine domain structure remains ***,we demonstrate the gate-driven evolution of labyrinthine domain structures in an itinerant ferromagnet Cr_(7)Te_(8).By combining electric transport measurements and micromagnetic finite difference simulations,we find that the hysteresis loop of anomalous Hall effect in Cr_(7)Te_(8)samples shows distinct features corresponding to the generation of labyrinthine domain *** labyrinthine domain structures are found to be electrically tunable via Li-electrolyte gating,and such gate-driven evolution in Cr_(7)Te_(8)originates from the reduction of the magnetic anisotropic energy with gating,revealed by our micromagnetic *** results on the gate control of anomalous Hall effect in an itinerant magnetic material provide an opportunity to understand the formation and evolution of labyrinthine domain structures,paving a new route towards electric-field driven spintronics.

关键词： rational electrolyte ferromagnetic