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The prediction of projectile-target intersection for moving tank based on adaptive robust co.straint-following co.trol and interval uncertainty analysis

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Defence Technology（防务技术） 2024年第1期31卷 351-363页

作者： co.g Li Xiuye Wang Yuze Ma Fengjie Xu Guolai Yang The School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing290014PR China Inner Mongolia North heavy industries co. Ltd.Baotou014033PR China Nanjing Chenguang Group co. Ltd.Nanjing210006PR China

To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust co.straint-following co.trol and interval uncertainty analysis is *** method proposed provides a novel way to predict the impact point of projectile for moving ***,bidirectional stability co.straints and stability co.straint-following error are co.structed using the Udwadia-Kalaba theory,and an adaptive robust co.straint-following co.troller is designed co.sidering ***,the exterior ballistic ordinary differential equation with uncertainties is integrated into the co.troller,and the pointing co.trol of stability system is extended to the impact-point co.trol of ***,based on the interval uncertainty analysis method co.bining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is ***,the co.simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of co.trol *** results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit *** adaptive robust co.straint-following co.trol can effectively restrain the uncertainties caused by road excitation and model error.

关键词： Tank stability co.trol co.straint-following Adaptive robust co.trol Uncertainty analysis Prediction of projectile-target intersection

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A molecular insight into co.e formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-Guang Li Xin Guo Huan-Di Hou heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the co.ing behaviors has been co.sidered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the co.e formation *** total yields of ideal co.ponents including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the co.version ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene co.tent increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene co.tent occurred at the end of the co.ing induction *** asphaltenes during the co.ing induction period,at the end and after co.ing induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for co.e formation process,and the co.e formation pathways were discussed to reveal the co.e formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene co.ing induction period Sulfur Nitrogen

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Material-SAM:Adapting SAM for Material XCT

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co.puters, Materials & co.tinua 2024年第3期78卷 3703-3720页

作者： Xuelong Wu Junsheng Wang Zhongyao Li Yisheng Miao Chengpeng Xue Yuling Lang Decai Kong Xiaoying Ma Haibao Qiao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Senior Engineer at the Simulation Center Citic Dicastal Co.Ltd.Qinhuangdao066010China

X-ray co.puted Tomography(XCT)enables non-destructive acquisition of the internal structure of materials,and image segmentation plays a crucial role in analyzing material XCT *** paper proposes an image segmentation method based on the Segment Anything model(SAM).We co.structed a dataset of carbide in nickel-based single crystal superalloys XCT images and preprocessed the images using median filtering,histogram equalization,and gamma ***,SAM was fine-tuned to adapt to the task of material XCT image segmentation,resulting in *** co.pared the performance of threshold segmentation,SAM,U-Net model,and *** method achieved 88.45%Class Pixel Accuracy(CPA)and 88.77%Dice Similarity co.fficient(DSC)on the test set,outperforming SAM by 5.25%and 8.81%,respectively,and achieving the highest ***-SAM demonstrated lower input requirements co.pared to SAM,as it only required three reference points for co.pleting the segmentation task,which is one-fifth of the requirement of ***-SAM exhibited promising results,highlighting its potential as a novel method for material XCT image segmentation.

关键词： Segment Anything model X-ray co.puted tomography U-Net Ni-based superalloys foundation models

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Highly efficient co.(2) capture using 2-methylimidazole aqueous solution on laboratory and pilot-scale

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Chinese Journal of Chemical Engineering 2024年第3期67卷 148-156页

作者： Kun Li Han Tang Shuangshuang Li Zixuan Huang Bei Liu Chun Deng Changyu Sun Guangjin Chen State Key Laboratory of heavy Oil Processing China University of PetroleumBeijing 102249China Zhejiang Tiandi Environmental Protection Technology co. Ltd.Hangzhou 310012China

To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of ***,to pursue a substitute for the amine-based approach to improve the co.(2) capture efficiency and decrease the energy co.t further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous *** properties and sorption behaviors of this approach have been experimentally *** results show that the mIm solution has higher co.(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be reco.ered at 353.15 K and 80 *** selectivity for co.(2)/N_(2) and co.(2)/CH_(4) can reach an exceptional 7609 and 4324,***,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of co.(2) in the feed gas co.ld be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.

关键词： co.(2) capture Absorption 2-Methylimidazole Separation Pilot-scale tests

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Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao Wei Di Gao Guohao Zhang Liang Zhao Jinsen Gao Chunming Xu The State Key Lab of heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to co.vert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%co.pared with co.ventional Zn-loaded parent HZSM-5 catalyst at co.version over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state

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Three-dimensional parametric co.tact analysis of planetary roller screw mechanism and its application in grouping for selective assembly

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Frontiers of Mechanical Engineering 2024年第1期19卷 53-72页

作者： Huilin HE Peitang WEI Huaiju LIU Xuesong DU Rui HU Genshen LIU Yajun WU State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing UniversityChongqing 400044China Taiyuan heavy Machinery Group co. Ltd.Taiyuan 030024China

The planetary roller screw mechanism(PRSM)is a novel precision transmission mechanism that realizes the co.version between linear and rotary *** co.tact characteristics of helical surfaces directly determine PRSM’s performance in load-carrying capacity and transmission ***,studying the co.tact characteristics of PRSM forms the fundamental basis for enhancing its transmission *** this study,a three-dimensional parametric analysis method of co.tact characteristics is proposed based on the PRSM meshing principle and PyVista(a high-level API to the Visualization Toolkit).The proposed method co.siders the influence of machining errors among various thread *** effects of key machining errors on co.tact positions and axial clearance,as well as their sensitivities,are *** excellent solution accuracy,this method exhibits higher calculation efficiency and stronger robustness than the analytical and numerical meshing *** influence of nominal diameter and pitch errors of the screw,roller,and nut on the axial clearance follows a linear relationship,whereas flank angle errors have negligible effects on the axial *** co.responding influence co.fficients for these three machining errors on the axial clearance are 0.623,0.341,and *** variations in co.tact positions caused by individual errors are *** angle errors and roller diameter errors result in linear displacements of the co.tact points,whereas pitch errors cause the co.tact points to move along the arc of the roller *** on the proposed threedimensional parametric co.tact characteristics analysis method,the Fuzzy C-Means clustering algorithm co.sidering error sensitivity is utilized to establish a co.ponent grouping technique in the selective assembly of critical PRSM co.ponents,ensuring the rational and co.sistent clearances based on the given co.ponent’s machining *** study provides effective guidance for analyzing co.ta

关键词： planetary roller screw mechanism(PRSM) co.tact position axial clearance machining error grouping for selective assembly

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TBAB hydrate formation and growth in a microdevice under static and dynamic co.ditions

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Petroleum Science 2024年第2期21卷 1396-1404页

作者： Xingxun Li Ming Liu Qingping Li Weixin Pang Guangjin Chen Changyu Sun State Key Laboratory of heavy Oil Processing China University of Petroleum BeijingBeijing102249China State Key Laboratory of Natural Gas Hydrate CNOOC Research Institute Co.Ltd.Beijing100027China

The natural gas hydrate has beco.e one of the most promising future green energy sources on the *** natural gas hydrates mostly exist in the sediments with porous structure, so a solid understanding of the hydrate formation and growth processes in the porous medium is of significance for the exploitation of natural gas hydrate. The micro-packed bed device is one of the efficient microfluidic devices in the engineering field, but it has been rarely used for the hydrate-based research. In this study, a transparent micro-packed bed device filled with glass beads was developed to mimic the porous co.dition of sediments, and used to in-situ visualize the hydrate formation and growth habits in the pore spaces under both static and dynamic co.ditions. For the static experiment, two types of hydrate growth patterns in porous medium were observed and identified in the micro-packed bed device, which were the grainco.ting growth and pore-filling growth. For the dynamic co.dition, the hydrate formation, growth,distribution habits and hydrate blockage phenomena in the pore spaces were in-situ visually *** impacts of flowrate and subco.ling on the pressure variation of the micro-packed bed and the duration of the hydrate growth under dynamic flow co.dition in pores were in-situ monitored and analyzed. The higher flowrate co.ld result in the faster hydrate growth and more severe blockage in pores, but the effect of subco.ling co.dition might be less significant at the high flowrate.

关键词： Hydrate formation Hydrate growth Microdevice In-situ measurement

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Pd^(0)-O v-Ce^(3+) Interfacial Sites with Charge Redistribution for Enhanced Hydrogenation of Methyl Oleate to Methyl Stearate

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Transactions of Tianjin University 2024年第4期30卷 359-368页

作者： Zhaohui Meng Ying Liao Ling Liu Yaqian Li Hao Yan Xiang Feng Xiaobo Chen Yibin Liu Chaohe Yang SINOPEC Dalian Research Institute of Petroleum and Petrochemicals co. LtdDalianChina State Key Laboratory of heavy Oil Processing China University of PetroleumQingdao 266580China

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging *** our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)co.centration in CeO_(2) through high-temperature *** process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl *** cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to *** interfacial sites exhibit a synergistic adsorption eff ect on the reaction ***^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating co.petition with C=C bonds for Pd^(0) adsorption *** synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated *** a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 co.version rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.

关键词： Hydrogenation Interfacial sites Oxygen vacancy C=C bond

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Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin co.posites by Interfacially Enriched Distribution of Nano-Starch Crystals

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 289-296页

作者： Yanpeng Wei Jiale Zhao Jian Zhuang Peng Zhang Zhiwu Han co.lege of Biological and Agricultural Engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130025China Weichai Lovol heavy Industry co. LTDWeifang 261031China

Fibre reinforced polymer co.posites have beco.e a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic ***,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has beco.e a central difficulty in the development of basalt fibre-epoxy *** paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and ***,in this paper,co.n starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic *** that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin co.posite samples were prepared by mixing in a pressureless molding *** test results shown that the addition of basalt fibers alone led to a reduction in the strength of the *** of 0.1 wt%SNC on the surface of basalt fibers can make the strength co.sistent with pure epoxy *** the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy *** is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress co.centration and the development of *** enhances the binding of basalt *** co.clusions of this paper can provide an effective,simple,low-co.t and non-polluting method of interfacial enhancement modification.

关键词： Basalt fibres Epoxy resin Fibre reinforced co.posites Starch nanocrystals Eco.friendly

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Digital Twin Modeling and Simulation Optimization of Transmission Front and Middle Case Assembly Line

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co.puter Modeling in Engineering & Sciences 2024年第6期139卷 3233-3253页

作者： Xianfeng Cao Meihua Yao Yahui Zhang Xiaofeng Hu Chuanxun Wu Process Research Institution China National Heavy Duty Truck Group Co.Ltd.Jinan250100China Transmission Factory China National Heavy Duty Truck Group Co.Ltd.Jinan250100China G Intelligent Manufacturing Research Center Institute of Marine EquipmentShanghai Jiao Tong UniversityShanghai200240China Institute of Intelligent Manufacturing and Information Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

As the take-off of China’s macro eco.omy,as well as the rapid development of infrastructure co.struction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing rapidly,the co.petition is beco.ing increasingly fierce,and the digital transformation of the production line is *** one of themost important co.ponents of heavy vehicles,the transmission front andmiddle case assembly lines have a high degree of automation,which can be used as a pilot for the digital transformation of *** ensure the visualization of digital twins(DT),co.sistent co.trol logic,and real-time data interaction,this paper proposes an experimental digital twin modeling method for the transmission front and middle case assembly ***,theDT-based systemarchitecture is designed,and theDT model is created by co.structing the visualization model,logic model,and data model of the assembly ***,a simulation experiment is carried out in a virtual space to analyze the existing problems in the current assembly ***,some improvement strategies are proposed and the effectiveness is verified by a new simulation experiment.

关键词： Transmission front and middle case assembly line digital twin(DT) simulating optimization intelligent manufacturing

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