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Saturated super-twisting sliding mode missile guidance

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Chinese Journal of Aeronautics 2022年第10期35卷 292-300页

作者： Mian GONG di ZHOU Xinguang ZOU School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Electronics and information Engineering Harbin Institute of TechnologyHarbin 150001China

This paper concentrates on developing a missile terminal guidance law against a highly maneuvering target whose maneuvering acceleration is very close to that of the missile or even exceeds the missile normal acceleration in a finite period of time.A new saturated super-twisting algorithm is proposed and applied to the design of missile guidance *** proposed algorithm has the advantages of simple structure,easy parameter tuning rules and a full utilization of the limit control *** designed saturated super-twisting sliding mode guidance law is then employed in a missile guidance *** and its superior performance against strong maneuvering targets is demonstrated.

关键词： Highly maneuvering target input saturation Missile guidance control Robust control Sliding mode control Super-twisting algorithm

Dual-radiation-chamber coordinated overall energy efficiency scheduling solution for ethylene cracking process regarding multi-parameter setting and multi-flow allocation

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Chinese Journal of Chemical Engineering 2021年第6期34卷 180-197页

作者： di Meng Cheng Shao Li Zhu institute of Advanced Control Technology Dalian University of TechnologyDalian 116024China

Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy *** of the interdependent relationships between multi-flow allocation and multi-parameter setting in cracking process,it is difficult to find the overall energy efficiency scheduling for the purpose of saving *** traditional scheduling solutions with optimal economic benefit are not applicable for energy efficiency scheduling issue due to the neglecting of recycle and lost energy,as well as critical operation parameters as coil outlet pressure(COP)and dilution *** addition,the scheduling solutions mostly regard each cracking furnace as an elementary unit,regardless of the coordinated operation of internal dual radiation chambers(DRC).Therefore,to improve energy utilization and production operation,a novel energy efficiency scheduling solution for ethylene cracking process is proposed in this ***,steam heat recycle and exhaust heat loss are considered in cracking process based on 6 types of extreme learning machine(ELM)based cracking models incorporating DRC operation and three operation parameters as coil outlet temperature(COT),COP,and dilution ratio according to semi-mechanism *** to provide long-term decision-making basis for energy efficiency scheduling,overall energy efficiency indexes,including overall output per unit net energy input(OONE),output-input ratio per unit net energy input(ORNE),exhaust gas heat loss ratio(EGHL),are designed based on input-output analysis in terms of material and energy ***,a multiobjective evolutionary algorithm based on decomposition(MOEA/D)is employed to solve the formulated multi-objective mixed-integer nonlinear programming(MOMiNLP)*** validities of the proposed scheduling solution are illustrated through a case *** scheduling results demonstrate that an optimal balance between multi-flow allocation,multi-parameter setting,and D

关键词： Ethylene cracking process Energy efficiency scheduling Overall energy efficiency indexes Dual radiation chamber Multiple operation parameters Multiple energy flows

Flow field design and experimental investigation of electrochemical machining on blisk

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Chinese Journal of Aeronautics 2022年第8期35卷 295-303页

作者： Jianwei GUO Dong ZHU di ZHU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Flow field is a crucial factor to influence the stability and surface quality in the electrochemical machining(ECM)of blisks.A four-way flow mode was proposed to eliminate mixing regions of electrolyte at the leading and tailing *** flow field models were described separately in this report:a W-shaped flow mode and a four-way flow *** flow field was analyzed through a finite element *** results showed that,in comparison with the W-shaped flow mode,the distribution of electrolyte flow was more uniformed and the mixed region in the flow channel was *** pressure of the leading and tailing edges inlets was optimized,and optimal pressure of 0.6 MPa was *** addition,verification experiments were performed,and the results showed that the stability,efficiency,and quality of the profiles of the blisk blade manufactured by ECM were enhanced in the new flow mode.

关键词： Blisk Electrochemical machining Electrolyte Flow field Surface quality

Robust load-balanced backbone-based multicast routing in mobile opportunistic networks

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Frontiers of Computer Science 2023年第4期17卷 109-125页

作者： di ZHANG Dong ZHAO uadong MA Beijing Key Laboratory of intelligent Telecommunications Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China

Mobile opportunistic network(MON)is an efficient way of communication when there is no persistent connection between *** in MONs can be used to efficiently deliver messages to multiple destination ***,because multiple destination nodes are involved,multicast routing is more complex than unicast and brings a higher communication ***-based routing can effectively reduce the network overhead and the complexity of routing ***,the load of backbone nodes is larger than that of regular *** the backbone node’s buffer is exhausted,it will have a significant impact on the performance of the routing *** balancing can improve the ability of backbone to deal with the change of network load,and backbone maintenance algorithm can provide backbone *** this paper,we propose a robust load-balanced backbone-based multicast routing scheme in *** the backbone construction algorithm,we transform the problem of backbone construction into a multi-objective optimization problem,and propose a multi-objective evolutionary algorithmbased backbone construction algorithm,namely LBMBCMOEA *** addition,in order to increase the robustness of the backbone-based routing scheme,we propose a localized multicast backbone maintenance algorithm(MBMA)to deal with the buffer exhaustion of backbone *** a backbone node’s residual buffer is insufficient,MBMA algorithm selects other nodes to replace the backbone *** results on extensive simulations show that when considering the node buffer size constraints,compared with previous backbone-based multicast routing schemes,our proposed algorithm has better performance,and when the node’s residual buffer is insufficient,MBMA algorithm can significantly improve the performance of the backbone-based multicast routing scheme.

关键词： mobile opportunistic network multicast multiobjective optimization backbone construction backbone maintenance

GridNet:efficiently learning deep hierarchical representation for 3D point cloud understanding

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Frontiers of Computer Science 2022年第1期16卷 1-9页

作者： Huiqun WANG di HUANG Yunhong WANG Laboratory of intelligent Recognition and image Processing School of Computer Science and EngineeringBeihang UniversityBeijing100191China

in this paper,we propose a novel and effective approach,namely GridNet,to hierarchically learn deep representation of 3D point *** incorporates the ability of regular holistic description and fast data processing in a single framework,which is able to abstract powerful features progressively in an efficient ***,to capture more accurate internal geometry attributes,anchors are inferred within local neighborhoods,in contrast to the fixed or the sampled ones used in existing methods,and the learned features are thus more representative and discriminative to local point *** delivers very competitive results compared with the state of the art methods in both the object classification and segmentation tasks.

关键词： 3D point clouds deep representations

Extreme Risk Measurement of Carbon Market Considering Multifractal Characteristics

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Journal of Systems Science & Complexity 2023年第6期36卷 2497-2514页

作者： ZHU Dandan ZHANG Chen PAN di School of Management Hefei University of TechnologyHefei230009China School of Economics and Management Shanghai University of Political Science and LawShanghai201701China Key Laboratory of Process Optimization and intelligent Decision-Making Hefei University of TechnologyHefei230009China

influenced by the global economy,politics,energy and other factors,the price of carbon market fluctuates *** is of great practical significance to explore a suitable measurement method of extreme risk of carbon *** that the return series of carbon market has the characteristics of leptokurtosis,fat tail,skewness and multifractal,and there maybe many extreme risk values in the carbon market,this paper introduces the Skewed-t distribution which can describe the characteristics of leptokurtosis,fat tail and skewness of return series into MSM model which can describe multifractal characteristic of return series to model volatility of carbon *** the basis,based on the extreme value theory,this paper constructs Skewed-t-MSM-EVT model to measure extreme risk of carbon *** paper chooses EUA market as the object to study extreme risk of carbon market,and draws the following conclusions:Skewed-t-MSM-EVT model has significantly higher prediction accuracy for carbon market's Va R than MSM-EVT models under other distributions(including normal distribution,t distribution,GED distribution);Skewed-t-MSM-EVT model is superior to traditional Skewed-t-FiGARCH-EVT and Skewed-t-GARCH-EVT models in predicting carbon market's Va *** research has important practical significance for accurately grasping the risk of carbon market and promoting energy conservation and emission reduction.

关键词： Carbon market extreme value theory multifractal Skewed-t distribution VaR

Signed PageRank on Online Rating Systems

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Journal of Systems Science & Complexity 2022年第1期35卷 58-80页

作者： GU Ke FAN Ying di Zengru Department of information Management Economics and Management CollegeBeijing Institute of Petrochemical TechnologyBeijing 102617China School of Systems Science Beijing Normal UniversityBeijing 100875China.

The ratings in many user-object online rating systems can reflect whether users like or dislike the objects,and in some online rating systems,users can directly choose whether to like an *** these systems can be represented by signed bipartite networks,but the original unsigned node evaluation algorithm cannot be directly used on the signed *** paper proposes the Signed Page Rank algorithm for signed bipartite networks to evaluate the object and user nodes at the same *** on the global information,the nodes can be sorted by the Signed Page Rank values in descending order,and the result is SR *** authors analyze the characteristics of top and bottom nodes of the real networks and find out that for objects,the SR Ranking can provide a more reasonable ranking which combines the degree and rating of node,and the algorithm also can help us to identify users with specific rating *** discussing the location of negative edges and the sensitivity of object SR Ranking to negative edges,the authors also explore that the negative edges play an important role in the algorithm and explain that why the bad reviews are more important in real networks.

关键词： Negative edges node evaluation online rating systems signed Page Rank

Control of a flexible rotor active magnetic bearing test rig: a characteristic model based all-coefficient adaptive control approach

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Control Theory and Technology 2014年第1期12卷 1-12页

作者： Long di Zongli LiN Charles L. Brown Department of Electrical and Computer Engineering University of VirginiaP.O. Box 400743 Charlottesville VA 22904-4743 U.S.A.

Active magnetic bearings （AMBs） have found a wide range of applications in high-speed rotating machinery industry. The instability and nonlinearity of AMBs make controller designs difficult, and when AMBs are coupled with a flexible rotor, the resulting complex dynamics make the problems of stabilization and disturbance rejection, which are critical for a stable and smooth operation of the rotor AMB system, even more difficult. Proportional-integral-derivative （PiD） control dominates the current AMB applications in the field. Even though PiD controllers are easy to implement, there are critical performance limitations associated with them that prevent the more advanced applications of AMBs, which usually require stronger robustness and performance offered by modern control methods such as H-infinity control and if-synthesis. However, these advanced control designs rely heavily on the relatively accurate plant models and uncertainty characterizations, which are sometimes difficult to obtain. in this paper, we explore and report on the use of the characteristic model based all-coefficient adaptive control method to stabilize a flexible rotor AMB test rig. in spite of the simple structure of such a characteristic model based all-coefficient adaptive controller, both simulation and experimental results show its strong performance.

关键词： Active magnetic bearings Adaptive control Characteristic modeling Flexible rotor Robustness

Rapid-developing Mg-based biodegradable materials:The editorial of the special issue on Mg-based functional materials-biomaterials section

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Journal of Magnesium and Alloys 2021年第6期9卷 2226-2228页

作者： di Mei Shaokang Guan School of Materials Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy Zhengzhou UniversityZhengzhou 450001HenanChina

Since physician Edward *** firstly tried to stop bleeding blood vessels with Mg wires in 1878[1],the history of Mg and its alloys as biomaterials has gone through more than 140 ***,in the latest 20 years,scientists from all over the world have carried out all-around research on Mg-based materials for the applications of vascular stents.

关键词： biomaterials bleeding alloys