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Startup drift compensation of RLG based on monotone constrained RBF neural network

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Chinese Journal of Aeronautics 2024年第11期37卷 355-365页

作者： Songlai HAN Mingcun ZHAO xuesong liu Xuecong liu Research Institute of Aerospace Technology Central South UniversityChangsha 410083China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Serious startup drift of the Ring Laser Gyroscope(RLG)is observed during cold startup process,which will dramatically degrade the performances of the corresponding Inertial Navigation System(INS).In this paper,correlation analysis method,which analyzes the relationship between the startup drift of the RLG and the temperature change,is used to determine the significant temperature-related terms during gyroscope *** on the significant temperature-related terms and the startup time length,a startup drift compensation model for RLG based on monotonicity-constrained Radial Basis Function(RBF)neural network is proposed and *** with the raw RLG data without compensation,the standard deviation of the RLG output with the proposed constrained RBF network model is decreased by more than 46%,and the peak-to-peak value is decreased by more than 35%.Compared with the traditional multiple regression model,the standard deviation and peak-to-peak value of the RLG output are decreased by more than 10%and 6%,*** with the common RBF network model,the standard deviation and peak-to-peak value of the RLG output are decreased by more than 8%and 3%,*** experiments also validate the effectiveness of the compensation model.

关键词： RLG Thermal effects Startup drift RBF Temperature compensation

Effect of Sheet Configuration on Microstructure and Mechanical Behaviors of Dissimilar Al–Mg–Si/Al–Zn–Mg Aluminum Alloys Friction Stir Welding Joints

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Journal of Materials Science & Technology 2016年第12期32卷 1378-1385页

作者： Zhongjie Yan xuesong liu Hongyuan Fang State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

Friction stir welding（FSW） was used to weld dissimilar Al-Mg-Si/Al-Zn-Mg aluminum alloys in this *** of sheet configuration on microstructure and mechanical properties of the joints were mainly *** showed that rather different joint cross sections were obtained when using different sheet *** β＇ phases can be observed at the heat affected zone（HAZ） of the Al-Mg-Si alloy side,which was the main factor affecting the tensile properties and the fatigue *** strengths of the dissimilar Al-Mg-Si/Al-Zn-Mg joints using both configurations were higher than that of the Al-Mg-Si FSW *** the Al-Zn-Mg alloy was located at the advancing side（AS）,the joints owned better fatigue properties due to the bridging effect of the big secondary phase particles.

关键词： Friction stir welding Dissimilar aluminum alloys Microstructure Tensile properties Fatigue life

Understanding the role of nano-TiO2 on the toxicity of Pb on *** through modeling-Is it additive or synergistic?

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Frontiers of Environmental Science & Engineering 2022年第5期16卷 57-67页

作者： xuesong liu Jianmin Wang Yue-Wern Huang Department of Civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65409USA The Center for Research in Energy and Environment(CREE) Missouri University of Science and TechnologyRollaMO 65409USA Department of Biological Sciences Missouri University of Science and TechnologyRollaMO 65409USA State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

Nano-TiO_(2) can remarkably increase lead(Pb)toxicity in aquatic ***,the mechanism of this toxicity,additive or synergistic,is not well *** explore this mechanism,we inspected the role of nano-TiO_(2) in the toxicity of Pb on Ceriodaphnia dubia(***),a model water flea species typically used for ecotoxicity *** effect of algae,a diet for aquatic organisms,on the effect of this binary mixture was also investigated.A two-compartment toxicokinetic(TK)-toxicodynamic(TD)modeling approach was used to quantify the Pb toxicity under these complex conditions and to develop critical parameters for understanding the mechanism of *** twocompartment modeling approach adequately described the Pb accumulation in the gut and in the rest of the body tissue under different nano-TiO_(2) concentrations,with and without algae,and predicted the toxicity response of *** indicated that increasing the nano-TiO_(2) concentration reduced the Pb tolerance level and concurrently increased the killing rate constant of ***,nano-TiO_(2) synergistically enhanced Pb *** remarkably reduced the toxicity of this binary mixture through reducing the Pb transfer rate to the body tissue and the killing rate,although it did not affect the Pb tolerance *** two-compartment modeling approach is useful in understanding the role of nanoparticles when assessing the overall toxicity of nanoparticles and other toxic elements in the environment.

关键词： Algae C.dubia Lead Nano-TiO2 Synergistic toxicity Two-compartment toxicokinetic-toxicodynamic model

Insight into the high-temperature tribological mechanism of VAlTiCrW high entropy alloy film:AlV_(3)O_(9)from tribochemistry

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Friction 2023年第7期11卷 1165-1176页

作者： xuesong liu Jun FAN Jibin PU Zhaoxia LU College of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Key Laboratory of Marine Materials and Related Technologies Key Laboratory of Marine Materials and Protective Technologies of Zhejiang ProvinceNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

High-entropy alloys have made significant progress in high mechanical properties,wear resistance,and corrosion resistance *** tribological properties,especially high-temperature lubrication,have become another sought *** this work,VAlTiCrW high-entropy alloy film with body-centered cubic(BCC)structure was prepared on superalloy substrate by magnetron *** is found that the VAlTiCrW film shows very low friction coefficient of 0.15 and a low wear rate of 10^(-5) orders of magnitude at 800℃.After 800℃oxidation,the film can still obtain a friction coefficient of no more than 0.2 at 700℃.XRD and TEM revealed the formation of ternary oxide AlV_(3)O_(9)with preferred orientation of(002)crystal plane with large spacing of 0.71 nm on the wear surface of the film,a high-temperature lubricating phase that has not been reported,realizes the low friction *** AlV_(3)O_(9)can be formed by tribochemical reaction under the thermal-mechanical action at 700℃,but pre-oxidation at 800℃is the prerequisite in order to form the precursors of V-rich and Al-rich oxide layer.

关键词： high entropy alloy high temperature friction AlV_(3)O_(9) oxide

Removal of airborne microorganisms emitted from a wastewater treatment oxidation ditch by adsorption on activated carbon

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Journal of Environmental Sciences 2011年第5期23卷 711-717页

作者： Lin Li Min Gao Junxin liu xuesong Guo Department of Water Pollution Control Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Bioaerosol emissions from wastewater and wastewater treatment processes are a significant subgroup of atmospheric aerosols. Most previous work has focused on the evaluation of their biological risks. In this study, however, the adsorption method was applied to reduce airborne microorganisms generated from a pilot scale wastewater treatment facility with oxidation ditch. Results showed adsorption on granule activated carbon （GAC） was an efficient method for the purification of airborne microorganisms. The GAC itself had a maximum adsorption capacity of 2217 CFU/g for airborne bacteria and 225 CFU/g for fungi with a flow rate of 1.50 m^3/hr. Over 85% of airborne bacteria and fungi emitted from the oxidation ditch were adsorbed within 80 hr of continuous operation mode. Most of them had a particle size of 0.65-4.7 μm. Those airborne microorganisms with small particle size were apt to be adsorbed. The SEM/EDAX, BET and Boehm＇s titration methods were applied to analyse the physicochemical characteristics of the GAC. Relationships between GAC surface characteristics and its adsorption performance demonstrated that porous structure, large surface area, and hydrophobicity rendered GAC an effective absorber of airborne microorganisms. Two regenerate methods, ultraviolet irradiation and high pressure vapor, were compared for the regeneration of used activated carbon. High pressure vapor was an effective technique as it totally destroyed the microorganisms adhered to the activated carbon. Microscopic observation was also carried out to investigate original and used adsorbents.

关键词： activated carbon adsorption airborne microorganisms oxidation ditch wastewater treatment facility

Effect of Welding Technologies on Decreasing Welding Residual Stress of Francis Turbine Runner

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Journal of Materials Science & Technology 2010年第10期26卷 951-956页

作者： Shude Ji Liguo Zhang xuesong liu Jianguo Yang School of Aerospace Engineering Shenyang Aerospace University Shenyang 110034 China State Key laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

On basis of the subsection welding and the local heating s reasonable technological parameters obtained by plane experiment,the welding residual stress field of some Francis turbine runner is regulated and *** the experimental plane with a thickness of 16 mm,the effect of subsection welding on decreasing welding residual stress of the prior welding section is obvious when the distance is less than 50 mm away from the end of latter welding *** the local heating,the best position,where the effect on decreasing the welding residual stress of plane is best,is 60 mm or so away from the edge of heating *** experimental results of runner show that the subsection welding can make the residual compressive stress engender in the blade dangerous area while the stress value is greatly influenced by the length of the welding section of blade *** local heating can further decrease the value of residual stress near blade outlet,while the local heating processed after heat treatment is better than that processed before heat treatment.

关键词： Blade Subsection welding Local heating Welding residual stress

Prediction of Large Structure Welding Residual Stress by Similitude Principles

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Journal of Materials Science & Technology 2009年第6期25卷 861-864页

作者： Shude Ji Liguo Zhang xuesong liu Jianguo Yang School of Aerospace Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

On basis of the similitude principles, the conception of virtual simulative component and the auxiliary value of welding residual stress, which is deduced by the welding conduction theory, the relation of the welding residual stress between the simulative component and the practical component was attained. In order to verify the correctness of the relation, the investigation was done from the view of the welding experiment and the numerical simulation about the simulative component and the practical component. The results show that the distribution of welding residual stress of the simulative component is the same as that of the practical component. The ratio of welding residual stress attained by the experiment or the simulation method between the practical runner and the simulative component was compared with the ratio obtained by the similitude principles. Moreover, the error is less than 10%. This provides a new idea to predict the welding stress distribution of large practical structure by the contractible physical model, which is important for the welding experiment and the numerical simulation.

关键词： Similitude principles Large welding structure Simulative components Welding residual stress

Control of Titanium Alloy Thin Plate Welding Distortion by Trailing Peening

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Journal of Materials Science & Technology 2003年第z1期19卷 184-186页

作者： xuesong liu Hongyuan FANG Shude JI Zhibo DONG State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China

The technology of trailing peening is a kind of promisingly bran-new technology which can be used to control weldingstress and distortion of Ti alloy thin plate. Control of TC4 Ti alloy thn plate welding stress and distortion underthe condition of conventional welding and trailing peening is performed, respectively. The results show that thetechnology of trailing peening effectively reduces deflection and transverse shrinkage of thin plate weldment. Themaximum deflection is decreased from 15 mm under the conditior of conventional welding to 5 mm, while the weldtransverse shrinkage is decreased from 0.5 mm to about 0.1 mm.

关键词： Control of residual stress and distortion, Trailing peening, TC4 Ti alloy

Decentralized wastewater treatment technologies and management in Chinese villages

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 929-936页

作者： xuesong GUO Zehang liu Meixue CHEN Junxin liu Min YANG State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Problems treating sewage in rural areas in China have attracted increasing attention in recent years. However, only 6% of rural areas had spray drainage and wastewater treatment systems by the end of 2010. It is necessary to assess the technologies currently used so that sewage treatment in rural areas can be developed appropriately, to provide reliable and affordable waste- water treatment, in these areas. We evaluated the sewage treatment technologies currently used in rural areas by conducting case studies on 62 facilities that had each been operating for at least one year. Our study was carried out between 2009 and 2011, and the aim was to assess the situation during that period and assess any problems involved in decentralized sewage treatment in villages. We found that decentralized sewage treatment is the most popular wastewater treatment method in villages, and that the most common primary treatment technology used in rural areas is the septic tank. Our investigation highlights the need to establish standards for assessing effluent quality, including a range of target pollutants. Our results also show that effluents should be reused to meet the local environmental requirements in different areas, especially in ecologically sensitive areas.

关键词： decentralized treatment strategy sustainable development village wastewater treatment situation