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Journal of Natural Gas Chemistry 2010年第5期19卷 471-476页

作者： bo Sun, Gang Li Xiaoxing Wang State Key Laboratory of Fine Chemicals Department of Catalytical Chemistry and Engineering Dalian University of Technology Dalian 116012 Liaoning China

Wormlike/lamellar microporous carbons were prepared by using long alkyl chain primary amine hydrochloride as the template and resorci- nol/formaldehyde as the carbon source under highly acidic conditions. The template can be eliminated by high temperature treatment under an inert atmosphere. The obtained carbon materials were characterized by N2 adsorption-desorption, transmission electron microscopy, ther- mogravimetry and scanning electron microscopy. The results show that dodecylamine hydrochloride surfactant can be used as the template of wormlike micropores structure while octadecylamine hydrochloride results in both lamellar and wormlike micropores. The obtained carbon materials have the similar pore size in the range of 0.5-0.59 nm, but with various morphologies such as monolith, spheres, and coralline. The microporous carbon obtained from dodecylamine hydrochloride surfactant shows good adsorption performance to remove the refractory sulfur compounds and nitrogen-containing compounds in fuel.

关键词： primary amine hydrochloride organic organic self-assemble microporous carbon adsorption

Mobile-robotic machining for large complex components:A review study

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Science China(Technological Sciences) 2019年第8期62卷 1388-1400页

作者： TAO bo ZHAO XingWei DING Han State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and Technology

Even though the robotic machining has achieved great success in machining of small components, it lacks the competence to machine large complex components, such as wind turbine blade, train carriage, and aircraft wing. In order to cope with this issue,the mobile machining robot system, which consists of a robot arm integrated with a mobile platform, is proposed to achieve the large workspace and high dexterity, and thus has the potential to machine the large complex components. However, due to the limitation of motion accuracy and structural stiffness, the current mobile-robots are hard to satisfy the high precision requirement of machining tasks. In this paper, some historical mobile-robotic machining systems are reviewed firstly, followed by some key techniques related to structure optimization, dynamics of the machining process, localization, and control techniques, which are fundamental for the structural stiffness and motion accuracy of mobile-robots. Finally, the prospect of mobile-robotic machining and the open questions are addressed.

关键词： robotic machining industrial robot mobile-robot accuracy stiffness

boundedness and liveness enforcement for labeled Petri nets using transition priority

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Journal of Electronic Science and Technology 2023年第4期21卷 75-90页

作者： Ye-Jia Liu Xun-bo Li School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control.

关键词： boundedness Control strategy Liveness Petri nets Priority Transition invariant

Microscopic states of Kerr black holes from boundary-bulk correspondence

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Chinese Physics C 2021年第1期45卷 383-391页

作者： Jing-bo Wang Institute for Gravitation and Astrophysics College of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China

It was previously claimed by the author that black holes can be considered as topological insulators. both black holes and topological insulators have boundary modes, and the boundary modes can be described by an effective BF theory. In this paper, the boundary modes on the horizons of black holes are analyzed using methods developed for topological insulators. BTZ black holes are analyzed first, and the results are found to be compatible with previous works. The results are then generalized to Kerr black holes, for which new results are obtained: dimensionless right-and left-temperatures can be defined and have well behavior in both the Schwarzschild limit a → 0 and the extremal limit a → M. Upon the Kerr/CFT correspondence, a central charge c = 12 Mr+ can be associated with an arbitrary Kerr black hole. Moreover, the microstates of the Kerr black hole can be identified with the quantum states of this scalar field. From this identification, the number of microstates of the Kerr black hole can be counted, yielding the Bekenstein-Hawking area law for the entropy.

关键词： boundary modes BTZ black hole Kerr black hole

Backstepping Based Global Exponential Stabilization of a Tracked Mobile Robot with Slipping Perturbation

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Journal of Bionic Engineering 2011年第1期8卷 69-76页

作者： bo Zhou Jianda Han Xianzhong Dai Key Laboratory of Measurement and Control of CSE (School of Automation Southeast University) Ministry of Education Nanjing 210096 P. R. China Shenyang Institute of Automation CAS Shenyang 110016 P. R. China

While the nonholonomic robots with no-slipping constraints are studied extensively nowadays, the slipping effect is inevitable in many practical applications and should be considered necessarily to achieve autonomous navigation and control purposes especially in outdoor environments. In this paper the robust point stabilization problem of a tracked mobile robot is discussed in the presence of track slipping, which can be treated as model perturbation that violates the pure nonholonomic constraints. The kinematic model of the tracked vehicle is created, in which the slipping is assumed to be a time-varying pa- rameter under certain assumptions of track-soil interaction. By transforming the original system to the special chained form of nonholonomic system, the integrator backstepping procedure with a state-scaling technique is used to construct the controller to stabilize the system at the kinematic level. The global exponential stability of the final system can be guaranteed by Lyapunov theory. Simulation results with different initial states and slipping parameters demonstrate the fast convergence, robustness and insensitivity to the initial state of the proposed method.

关键词： tracked mobile robot nonholonomic system stabilization backstepping Lyapunov function

A Novel Competition-Based Coordination Model With Dynamic Feedback for Multi-Robot Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第10期10卷 2029-2031页

作者： bo Peng Xuerui Zhang Mingsheng Shang Chongqing Key Laboratory of Big Data and Intelligent Computing Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714 Chongqing School University of Chinese Academy of SciencesChongqing 400714China Chongqing Key Laboratory of Big Data and Intelligent Computing Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China

Dear Editor, Task allocation strategies are important in multi-robot systems and have been intensely investigated by researchers because they are critical in determining the performance of the system. In this letter, a novel competition-based coordination model is proposed to solve the multi-robot task allocation problem and applied to a multi-robot object tracking scenario.

关键词： robot Robot Dynamic

Integral—Type Darboux Transformations for the mKdV Hierarchy with Self—COnsistent Sources

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Communications in Theoretical Physics 2002年第6X期38卷 641-648页

作者： ZENGYun-bo MAWen-Xiu 等 DepartmentofMathematicalSciences TsinghuaUniveersityBeijing100084China DepartmentofMathematics CityUniversityofHongKongKowloonHongKongChina

We present integral-type Darboux transformation for the mKdV hierarchy and for the mKdV hierarchy withself-consistent sources. In contrast with the normal Darboux transformation, the integral-type Darboux transformationscan offer non-auto-Backlund transformation between two (2n + 1)-th mKdV equations with self-consistent sources withdifferent degrees. This kind of Darboux transformation enables us to construct the N-soliton solution for the mKdVhierarchy with self-consistent sources. We also propose the formulas for the m times repeated integral-type Darbouxtransformations for both mKdV hierarchy and mKdV hierarchy with self-consistent sources.

关键词：孤子方程积分型Darboux变换自洽源非线性偏微分方程

Dynamic leakage mechanism of gas drainage borehole and engineering application

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International Journal of Mining Science and Technology 2018年第3期28卷 505-512页

作者： Zhang Junxiang Li bo Sun Yuning School of Energy Science and Engineering Henan Polytechnic University Jiaozuo 454003 China State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University Jiaozuo 454003 China Collaborative Innovation Center of Coal Safety Production of Henan Province Jiaozuo 454003 China State and Local Joint Engineering Laboratory for Gas Drainage & Ground Control of Deep Mines Henan Polytechnic University fiaozuo 454003 China

borehole leakage not only affects the gas drainage effect but also presents considerable risk to human security. For the research on the leakage mechanism of gas drainage borehole, the rheological and visco-elastic-plastic characteristics were considered to establish the mechanical model of coal mass around borehole, which is used to analyze the leakage mechanism and deduce the dynamic leakage model. On the basis of the real coal seam conditions, the variation rules of the stress, leakage ring, and air leakage amount were analyzed through numerical simulation, and the influence factors of air leakage amount were also investigated to provide the theoretical basis for the sealing technology. Results show that the air leakage amount of borehole is inversely proportional to the increase in supporting stress and sealing length, and directly correlated with the increase in borehole radius and softening modulus. Using theoretical analysis, we design a novel active supporting sealing technology that can use grouting material to seal the fractures to reduce the leakage channels and also provide supporting stress to prevent borehole deformation. The engineering test results indicate that the average gas concentration with the novel active supporting sealing technology is increased by 162.12% than that of traditional polyurethane sealing method. Therefore, this technology not only effectively resolves borehole leakage but also significantly improves the gas drainage effect.

关键词： borehole leakage Gas drainage Leakage mechanism Numerical simulation Supporting stress

Intersection theory rules symbology

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 93-104页

作者： Jiaqi Chen bo Feng Lilin Yang Beijing Computational Science Research Center Beijing 100084China Zhejiang Institute of Modern Physics School of PhysicsZhejiang UniversityHangzhou 310027China Peng Huanwu Center for Fundamental Theory Hefei 230026China

We propose a novel method to determine the structure of symbols for any family of polylogarithmic Feynman *** the d log-bases and simple formulas for the leading order and next-to-leading contributions to the intersection numbers,we give a streamlined procedure to compute the entries in the coefficient matrices of canonical differential equations,including the symbol letters and the rational *** also provide a selection rule to decide whether a given matrix element must be *** symbol letters are deeply related to the poles of the integrands and also have interesting connections to the geometry of Newton *** method can be applied to many cutting-edge multi-loop *** simplicity of our results also hints at the possible underlying structure in perturbative quantum field theories.

关键词： scattering amplitude Feynman integral symbology

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Observer-based control for the platform of a tethered space robot

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Chinese Journal of Aeronautics 2018年第8期31卷 1786-1796页

作者： Guang ZHAI Heming ZHENG bo ZHANG Aerospace Engineering School Beijing Institute of TechnologyBeijing 100081China Aerospace System Engineering Shanghai Shanghai 201109China

This paper addresses the attitude control problem of a space tethered robot platform in the presence of unknown external disturbance caused by a connecting elastic tether. The tethergenerated unknown disturbance leads to tremendous challenges for attitude control of the *** this work, the perturbed attitude dynamics of the platform are derived with a consideration of the libration of the elastic tether, and then with the purpose of compensating the unknown disturbance, major attention is dedicated to develop a nonlinear disturbance observer based on gyros measurements, after which, an adaptive attitude scheme is proposed by combining the disturbance observer with a sliding mode controller. Finally, benefits from the observer based on an adaptive controller are validated by series of numerical simulations.

关键词： Adaptive control Attitude dynamics Disturbance observerSliding mode controlTethered space robot