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An improved artificial bee colony algorithm with MaxTF heuristic rule for two-sided assembly line balancing problem

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Frontiers of Mechanical Engineering 2019年第2期14卷 241-253页

作者： xiaokun duan Bo WU Youmin HU Jie LIU Jing XIONG School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering Hubei Engineering UniversityXiaogan 432000China

Two-sided assembly line is usually used for the assembly of large products such as cars,buses,and *** the development of technical progress,the assembly line needs to be reconfigured and the cycle time of the line should be optimized to satisfy the new assembly ***-sided assembly line balancing with the objective of minimizing the cycle time is called *** paper proposes an improved artificial bee colony(IABC)algorithm with the MaxTF heuristic *** the heuristic initialization process,the MaxTF rule defines a new task's priority *** the basis of priority weight,the assignment of tasks is reasonable and the quality of an initial solution is *** the IABC algorithm,two neighborhood strategies are embedded to balance the exploitation and exploration abilities of the *** employed bees and onlooker bees produce neighboring solutions in different promising regions to accelerate the convergence ***,a well-designed random strategy of scout bees is developed to escape local *** experimental results demonstrate that the proposed MaxTF rule performs better than other heuristic rules,as it can find the best solution for all the 10 test cases.A comparison of the IABC algorithm and other algorithms proves the effectiveness of the proposed IABC *** results also denote that the IABC algorithm is efficient and stable in minimizing the cycle time for the TALBP-2,and it can find 20 new best solutions among 25 large-sized problem cases.

关键词： two-sided assembly line balancing problem artificial bee colony algorithm heuristic rules time boundary

Rapid Screening of Nine Illicit Drugs in Human Blood and Urine by Direct Analysis in Real‑Time Mass Spectrometry

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Journal of Forensic Science and Medicine 2019年第3期5卷 136-140页

作者： Ying Zhang Wenfang Zhang Guobin Xin Li Liu xiaokun duan Charles Liu Forensic Science Service of Beijing Public Security Bureau Key Laboratory of Forensic ToxicologyMinistry of Public SecurityBeijingChina ASPEC Technologies Limited BeijingChina

We aimed to establish for the rapid detection of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in human blood and urine by direct analysis in real‑time coupled with tandem mass spectrometry(DART‑MS/MS).These samples were extracted by acetonitrile‑methanol(V/V=4:1),using DART 12 Dip‑it automatic sampling *** were injected at 400℃,and analyzed by positive ion and multiple reaction monitoring *** detection limits of morphine,O6‑Monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin were 100,50,50,100,20,20,10,1,and 0.01 ng/mL,*** practical cases contained methamphetamine,codeine,cocaine,and O6‑monoacetylmorphine were detected accurately and *** method has the advantages of high sensitivity and good *** sample processing is simple and can be analyzed in a short *** method is suitable for the analysis of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in some practical cases.

关键词： Direct analysis in real‑time mass spectrometry forensic toxicological analysis illicit drugs rapid screening

A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

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Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-Ren duan Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

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Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-Ren duan Center for Control Theory and Guidance Technology Harbin Institute of Technology Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

Stabilization Controller of An Extended Chained Nonholonomic System With Disturbance:An FAS Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1262-1273页

作者： Zhongcai Zhang Guangren duan School of Engineering Qufu Normal UniversityRizhao 276826China Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055 Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

This study examines the stabilization issue of extended chained nonholonomic systems(ECNSs)with external *** the existing approaches,we transform the considered system into a fully actuated system(FAS)model,simplifying the stabilizing controller *** implement a separate controller design and propose exponential stabilization controller and finite-time stabilization controller under finite-time disturbance observer(FTDO)for the two system *** addition,we discuss the specifics of global stabilization control *** approach demonstrates that two system states exponentially or asymptotically converge to zero under the provided switching stabilization control strategy,while all other system states converge to zero within a finite time.

关键词： design stabilization system

Triangle-free Graphs with Three Positive Eigenvalues

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Algebra Colloquium 2024年第3期31卷 525-540页

作者： Fang duan School of Mathematical Sciences Xinjiang Normal UniversityUrumqi 830017China

A graph G is called triangle-free if G does not contain any triangle as its induced *** G_(n)be the set of triangle-free graphs of order n each of which has three positive *** this paper,we find 20 specific graphs in G_(n),each of which has nullity no more than 2,and we show that in terms of three graph transformations all the other graphs of G_(n)can be constructed from these 20 specific ***,we completely characterize the triangle-free graphs with exactly three positive eigenvalues.

关键词： positive(negative)inertia index nullity triangle-free graph

Distributed velocity-free formation tracking control for clustered UAVs under virtual leader-follower framework

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Science China(Technological Sciences) 2024年第5期67卷 1538-1552页

作者： ZHANG ZhaoYu duan HaiBin School of Automation Science and Electrical Engineering Beihang UniversityBeijing100083China

The collective formation control problem of a cluster of rotorcraft unmanned aerial vehicles(UAVs)is investigated in this *** consensus tracking towards formation centroid with following UAVs forming a predefined configuration around the leader is considered as the *** prior studies,the information of the central reference trajectory,which is deemed as a virtual leader in the leader-follower topology,is not directly accessible for partial nodes through the communication ***,a novel distributed formation tracking control scheme is ***,a decentralized saturation observer is employed to estimate the reference acceleration signal of the virtual *** the absence of linear velocity measurement,two sliding manifolds are proposed by introducing the relative discrepancy terms of position and *** a smooth saturation operator in the form of a sigmoid function is applied to generate the command force ***,under the dilemma of constrained capabilities of the airborne sensors equipped on the rotorcrafts,the angular velocity is difficult to *** cascaded auxiliary attitude error systems are established on each rotorcraft system to synthesize the rotating torque with no need to require the angular velocity *** to the strong coupling and nonlinearity of the rotorcraft UAV system,the command angular velocity and the derivatives of command input are hard to *** a continuous nonlinear differentiator is proposed to work with the difficulties in deriving the explicit expression of system ***,a detailed stability analysis is conducted progressively on the angular control loop,reference trajectory observer loop,and the position control loop.A simulation scheme for a cluster of four rotorcraft UAVs tracking sinusoidal trajectory are presented and the formation control results are proven advantageous in comparison with the control protocol in previous literature.

关键词： distributed formation control unmanned rotorcraft clusters velocity-free tracking nonlinear differentiator

A comprehensive research on wear resistance of GH4169 superalloy in longitudinal-torsional ultrasonic vibration side milling with tool wear and surface quality

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Chinese Journal of Aeronautics 2024年第4期37卷 556-573页

作者： Baoqi CHANG Zhaoxi YI Fen ZHANG Lian duan Ji-an duan School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance and Complex Manufacturing Central South UniversityChangsha 410083China School of Physics and Electronics Central South UniversityChangsha 410083China

To improve the service and machining performance of the workpiece, the tool wear mechanisms, surface machining quality, and wear resistance in conventional side milling(CSM)and longitudinal-torsional ultrasonic vibration side milling(LTUVSM) of GH4169 superalloy at different cutting lengths are investigated systematically. Tool wear mechanisms are revealed and the correlation between machined surface quality with tool wear is analyzed correspondingly. Tool wear patterns mainly include adhesive wear, diffusion wear, abrasive wear, and chipping *** surface quality is achieved in LTUVSM due to a maximum reduction of flank wear bandwidth and wear rate by 71.9% and 71.5%, respectively, compared to CSM. The friction coefficient,initial wear stage time, and wear volume of dry sliding wear were measured to evaluate the workpiece wear resistance. The maximum reductions in friction coefficient and wear volume in LTUVSM are 18.2% and 15.8% compared to CSM. The regular ultrasonic vibration textures suppress the friction and the growth of contact nodes in the contact area, decreasing the degree of surface wear, which is demonstrated by a 38.8% increase in initial wear stage time compared to *** conclusion, the workpiece in LTUVSM exhibits higher wear resistance because of the improvement of tool wear and the guarantee of surface quality.

关键词： Dry sliding wear Surface quality Tool wear Ultrasonic vibration Wear resistance

Nanostructured lubricant additives for titanium alloy:Lubrication by the solid-liquid interface with Coulomb repulsion

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Friction 2024年第7期12卷 1564-1579页

作者： Linlin duan Dan JIA Jian LI Jianfang LIU Haitao duan State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials ProtectionWuhan 430030China Hubei Longzhong Laboratory Xiangyang 441000China College of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430030China

In this work,the advantage of Coulomb repulsion in the intermolecular forces experienced by molecules on the solid–liquid nanosized contact interface is taken,and the superior friction-reducing property of Cu_(3)(PO_(4))2·3H_(2)O(CuP)oil-based additives has been confirmed for titanium ***-dimensional(3D)CuP nanoflowers(CuP-Fs)with a strong capillary absorption effect are prepared to achieve the homogeneous mixing of solid CuP and lubricating *** by CuP-Fs additives for titanium alloy,friction coefficient(COF)can be reduced by 73.68%,and wear rate(WR)reduced by 99.69%.It is demonstrated that the extraordinary friction-reducing property is due to the repulsive solid–liquid interface with low viscous shear force originating from Coulomb repulsion between polar water molecules in CuP and non-polar oil ***,any steric hindrance or connection between this repulsive solid–liquid interface will trigger the adhesion and increase the viscous shear force,for example,dispersant,hydrogen bondings,and shaky adsorbed water ***,the lamellar thickness of CuP and the molecular size of lubricant both have a great influence on tribological *** the lubrication mechanism based on interface Coulomb repulsion is proposed that may help broaden the scope of the exploration in low-friction nanomaterial design and new lubricant systems.

关键词： lubrication nanomaterial additive solid-liquid interface wear