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Adaptive robust feedback control of moving target tracking for all-Electrical tank with uncertainty

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Defence technology（防务技术） 2022年第4期18卷 626-642页

作者： Yu-ze Ma Guo-lai Yang Qin-qin Sun Xiu-ye Wang Zong-fan Wang The school of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

A moving target tracking control problem for marching tank based on adaptive robust feedback control scheme is addressed.A series of preparations is needed for tank gun before shooting a target,the purpose of this paper is to design a control system to fulfill two requirements in this process:the turretbarrel system of tank needs to be adjusted from off-target position to command position and point to the moving target stably when there are strong uncertainties(modeling error,uncertain disturbance with unknown boundaries and road excitation) in the *** the characteristic of coupled interaction,the first thing we do in this paper is to build a coupled analysis model of turret-barrel system with uncertainty term in state-space ***,an adaptive robust feedback control scheme is proposed by adding adaptive law to overcome the ***,multi-body dynamics software is used to establish the mechanical mechanism of the tank,and DC-motor module is established in SIMULINK environment,thus the target information and tracking error of the control system is collected and transferred,the gear-ball screw is derived directly by the output torque of the DC-motor ***,the control system and the 3D model are combined together by means of Recur Dyn/SIMULINK co-simulation,the turret-barrel system of tank can approximately track the moving target in a certain *** the adaptive robust feedback control,the target action is completely followed when the target location is constantly changing.

关键词： Mechanical system Tank stability Uncertainty Road excitation Adaptive robust feedback control

Hydrothermal Desulfurization on Porous Sulfonated CFR-PEEK Surface Structure Used for Implant Application

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Journal of Bionic Engineering 2023年第2期20卷 748-761页

作者： Jingdan Li Wen Qin Patrick Osei Lartey Yulong Fu Jing Ma school of Material science and Engineering Taiyuan University of TechnologyTaiyuan030024China

The poor wear resistance and bio-inertness surface of polyetheretherketone(PEEK)limits the implant applications of PEEK and its *** fiber(CFR)was used to boost the wear resistance of PEEK;however,the bioactivity of carbon fiber-reinforced polyetheretherketone(CFR-PEEK)composites is even *** bioactivity of CFR-PEEK can be enhanced by constructing 3D porous ***,large number of sulfur component introduced by sulfonation shows cytotoxicity and can cause damage to human ***,the sulfur component affects the cytotoxicity and bioactivity of sulfonated CFR-PEEK(SCFR-PEEK).Hydrothermal treatment can sweep away the sulfur component in the 3D porous structure of ***,the changes in crystallinity and hardness after hydrothermal treatment may also affect the wear ***,the effect of hydrothermal temperature on wear resistance,cytotoxicity and bioactivity of SCFR-PEEK were *** this work,the samples with hydrothermal temperature 90–120℃exhibited high wear *** 3D pore structure of SCFR-PEEK unchanged after hydrothermal treatment,and the sulfur component in the 3D pore structure gradually decreased with increasing hydrothermal temperature by SEM images and EDS *** addition,SCFR-PEEK treated in 90–120℃.Exhibited low cytotoxicity and high bioactivity,which is beneficial for the implant materials.

关键词： Biomaterials Hydrothermal treatment Cytotoxicity Microstructure Surface structure

Adaptive RISE Control of Winding Tension with Active Disturbance Rejection

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 135-145页

作者： Junjie Mi Jianyong Yao Wenxiang Deng school of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A winding system is a time-varying system that considers complex nonlinear characteristics,and how to control the stability of the winding tension during the winding process is the primary problem that has hindered development in this field in recent *** nonlinear factors affect the tension in the winding process,such as friction,structured uncertainties,unstructured uncertainties,and external *** terms severely restrict the tension tracking *** tension control strategies are mainly based on the composite control of the tension and speed loops,and previous studies involve complex decoupling *** to the large number of calculations required for this method,it is inconvenient for practical engineering *** simplify the tension generation mechanism and the influence of the nonlinear characteristics of the winding system,a simpler nonlinear dynamic model of the winding tension was *** adaptive method was applied to update the feedback gain of the continuous robust integral of the sign of the error(RISE).Furthermore,an extended state observer was used to estimate modeling errors and external *** model disturbance term can be compensated for in the designed RISE *** asymptotic stability of the system was proven according to the Lyapunov stability ***,a comparative analysis of the proposed nonlinear controller and several other controllers was *** results indicated that the control of the winding tension was significantly enhanced.

关键词： Winding tension Continuous robust integral of the sign of the error(RISE)control Adaptive control Disturbance compensation Extended state observer(ESO) Tension control

B effects on crystallization and magnetic properties of Pr_(9.44)Fe_(90.56-x)B_x(x=7.16, 4.76) nanocomposite magnets

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Acta Metallurgica Sinica(English Letters) 2010年第5期23卷 321-326页

作者： Caiyin YOU Na TIAN Zhengxin LU Liling GE Xiaotian JING school of Materials science and Engineering Xi an University of Technology Xi an 710048 China

Magnetic properties, phase evolution and microstructures of Pr9.44Fe90.56-xBx （x=7.16 and 4.76） nanocomposite magnets have been investigated. Both as-spun ribbons exhibit two-step demagnetization curves, indicating the feature of partial crystallization. By using di？erential scanning calorimeter （DSC） measurements, remained amorphous phase of ribbon with x=7.16 shows a higher crystallization temperature. At optimum annealing temperature of 650℃ for 10 min, better magnetic properties, Mr=1.01 T, jHc=796 kA/m and （BH）max=136 kJ/m3 were obtained in the sample with x=4.76. Transmission electron microscopy （TEM） observation confirms that the sample with x=4.76 possesses much finer grain size, which causing a better exchange coupling between soft and hard magnetic grains.

关键词： Nanocomposite magnet Melt spinning Exchange coupling Microstructure

Strengthening granulation behavior of specularite concentrates based on matching of characteristics of iron ores in sintering process

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Journal of Iron and Steel Research International 2018年第10期25卷 1017-1025页

作者： Sheng-li Wu Zhi-gang Que Kai-lang Li school of Metallurgical and Ecological EngineeringUniversity of science and technology Beijing Beijing 100083 China

Specularite concentrates have advantages of high ferrous grade, less harmful impurities and low price. However, the small size and poor granulation behavior of specularite concentrates consequently deteriorate the permeability of sinter bed and reduce the productivity of sinter, resulting in un-effective utilization in sintering process. The granulation experiments were carried out when specularite concentrates matched with five kinds of fine or coarse ores, and the effects of surface property and wettability of fine or coarse ores on granulation behavior of specularite concentrates were investigated. Then, the optimized ore blending recipes were proposed to strengthen the granulation behavior of specularite concentrates. The results indicated that the growth index increased with increasing the specific surface area of fine ores and had a positive linear correlation with the circularity degree of coarse ores, whereas negative correlations exist between the growth index and the contact angle of fine or coarse ores. Compared with the concentrates, the growth index increased by approximately 22% scheme of blended ores containing 15 mass% specularite in the case of using Ore-A and Ore-E with greater surface property and higher wettability to replace all of Ore-B and half of Ore-D, respectively. Furthermore, the vertical sintering speed and the productivity of sinter improved by approximately 23% and 20%, respectively.

关键词： Iron ore sinter Granulation behavior Specularite concentrate Surface property Wettability

BEM/FDM Conjugate Heat Transfer Analysis of a Two-dimensional Air-cooled Turbine Blade Boundary Layer

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Journal of Thermal science 2008年第3期17卷 199-206页

作者： Wang Zhenfeng Yan Peigang Guo Zhaoyuan Han Wanjin school of Energy science and Engineering Harbin Institute of Technology Harbin 150001 China

A coupled boundary element method （BEM） and finite difference method （FDM） are applied to solve conjugate heat transfer problem of a two-dimensional air-cooled turbine blade boundary layer. A loosely coupled strategy is adopted, in which each set of field equations is solved to provide boundary conditions for the other. The Navier-Stokes equations are solved by HIT-NS code. In this code, the FDM is adopted and is used to resolve the convective heat transfer in the fluid region. The BEM code is used to resolve the conduction heat transfer in the solid region. An iterated convergence criterion is the continuity of temperature and heat flux at the fluid-solid interface. The numerical results from the BEM adopted in this paper are in good agreement with the results of analytical solution and the results of commercial code, such as Fluent 6.2. The BEM avoids the complicated mesh needed in other computation method and saves the computation time. The results prove that the BEM adopted in this paper can give the same precision in numerical results with less boundary points. Comparing the conjugate results with the numerical results of an adiabatic wall flow solution, it reveals a significant difference in the distribution of metal temperatures. The results from conjugate heat transfer analysis are more accurate and they are closer to realistic thermal environment of turbines.

关键词： Conjugate heat transfer Boundary elements Finite difference Air-cooled gas turbine.

piEnPred:a bi-layered discriminative model for enhancers and their subtypes via novel cascade multi-level subset feature selection algorithm

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Frontiers of Computer science 2021年第6期15卷 175-185页

作者： Zaheer Ullah KHAN Dechang PI Shuanglong YAO Asif NAWAZ Farman ALI Shaukat ALI school of Computer science and technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China school of Computer science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computer science Islamia College University PeshawarPeshawar 25000Pakistan

Enhancers are short DNA cis-elements that can be bound by proteins(activators)to increase the possibility that transcription of a particular gene will *** Enhancers perform a significant role in the formation of proteins and regulating the gene transcription *** diseases such as cancer,inflammatory bowel disease,Parkinson’s,addiction,and schizophrenia are due to genetic variation in *** the current study,we havemade an effort by building,amore robust and novel computational a bi-layered *** representative feature vector was constructed over a linear combination of six *** optimum Hybrid feature vector was obtained via the Novel Cascade Multi-Level Subset Feature selection(CMSFS)*** first layer predicts the enhancer,and the secondary layer carries the prediction of their *** baseline model obtained 87.88%of accuracy,95.29%of sensitivity,80.47%of specificity,0.766 of MCC,and 0.9603 of a roc value on ***,the model obtained 68.24%,65.54%,70.95%,0.3654,and 0.7568 as an Accuracy,sensitivity,specificity,MCC,and ROC values on layer-2 *** an independent dataset on layer-1,the piEnPred secured 80.4%accuracy,82.5%of sensitivity,78.4%of specificity,and 0.6099 as MCC,***,the proposed predictor obtained 72.5%of accuracy,70.0%of sensitivity,75%of specificity,and 0.4506 of MCC on layer-2,*** proposed method remarkably performed in contrast to other state-of-the-art *** the convenience of most experimental scientists,a user-friendly and publicly freely accessible web server@/bienhancer dot pythonanywhere dot com has been developed.

关键词： enhancer enhancer types novel CM-SFS algorithm feature selection SVM

Efficient Direct Decomposition of NO over La_(0.8)A_(0.2)NiO_(3)(A=K, Ba, Y) Catalysts under Microwave Irradiation

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Journal of Wuhan University of technology(Materials science) 2024年第1期39卷 17-23页

作者：王浩 ZHAO Zijian DUAN Xinghui ZHOU Shijia school of Materials science and Engineering Wuhan University of TechnologyWuhan 430070China

La_(0.8)A_(0.2)NiO_(3) (A=K,Ba,Y) catalysts supported on the microwave-absorbing ceramic heating carrier were prepared by the sol-gel *** crystalline phase and the catalytic activity of the La_(0.8)A_(0.2)NiO_(3)catalysts were characterized by XRD and H_(2) temperature-programmed reduction (TPR).The effects of reaction temperature,oxygen concentration,and gas flow rate on the direct decomposition of nitric oxide over the synthesized catalysts were studied under microwave irradiation (2.45 GHz).The XRD results indicated that the La_(0.8)A_(0.2)NiO_(3) catalysts formed an ABO_(3) perovskite structure,and the H_(2)-TPR results revealed that the relative reducibility of the catalysts increased in the order of La_(0.8)K_(0.2)NiO_(3)>La_(0.8)Ba_(0.2)NiO_(3)>La_(0.8)Y_(0.2)Ni O_(3).Under microwave irradiation,the highest NO conversion amounted to 98.9%,which was obtained with the La_(0.8)K_(0.2)NiO_(3) catalyst at 400℃.The oxygen concentration did not inhibit the NO decomposition on the La_(0.8)A_(0.2)NiO_(3) catalysts,thus the N_(2) selectivity exceeded 99.8%under excess oxygen at 550℃.The NOconversion of the La_(0.8)A_(0.2)NiO_(3) catalysts decreased linearly with the increase in the gas flow rate.

关键词： microwave catalysis direct decomposition of NO microwave-absorbing heating ceramics perovskite catalyst

Reinforcement Learning-Empowered Graph Convolutional Network Framework for Data Integrity Attack Detection in Cyber-Physical Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 797-806页

作者： Edeh Vincent Mehdi Korki Mehdi Seyedmahmoudian Alex Stojcevski Saad Mekhilef school of science Computingand Engineering TechnologiesSwinburne University of TechnologyMelbourneAustralia

The massive integration of communication and information technology with the large-scale power grid has enhanced the efficiency, safety, and economical operation of cyber-physical systems. However, the open and diversified communication environment of the smart grid is exposed to cyber-attacks. Data integrity attacks that can bypass conventional security techniques have been considered critical threats to the operation of the grid. Current detection techniques cannot learn the dynamic and heterogeneous characteristics of the smart grid and are unable to deal with non-euclidean data types. To address the issue, we propose a novel Deep-Q-Network scheme empowered with a graph convolutional network (GCN) framework to detect data integrity attacks in cyber-physical systems. The simulation results show that the proposed framework is scalable and achieves higher detection accuracy, unlike other benchmark techniques.

关键词： Deep reinforcement learning graph convolutional network heterogeneous smart grid network