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New coordination scheme for multi-robot systems based on state space models

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Journal of Systems Engineering and Electronics 2008年第4期19卷 722-734页

作者： Xie Wenlong Su jianbo Lin Zongli Dept. of Automation Shanghai Jiaotong Univ. Shanghai 200240 P. R. China Charles L. Brown Dept. of Electrical and Computer Engineering Univ of Virginia Charlottesville VA 22904-4743 USA

A new coordination scheme for multi-robot systems is proposed. A state space model of the multi- robot system is defined and constructed in which the system＇s initial and goal states are included along with the task definition and the system＇s internal and external constraints. Task accomplishment is considered a transition of the system state in its state space （SS） under the system＇s constraints. Therefore, if there exists a connectable path within reachable area of the SS from the initial state to the goal state, the task is realizable. The optimal strategy for the task realization under constraints is investigated and reached by searching for the optimal state transition trajectory of the robot system in the SS. Moreover, if there is no connectable path, which means the task cannot be performed Successfully, the task could be transformed to be realizable by making the initial state and the goal state connectable and finding a path connecting them in the system＇s SS. This might be done via adjusting the system＇s configuration and/or task constraints. Experiments of multi-robot formation control with obstacles in the environment are conducted and simulation results show the validity of the proposed method.

关键词： multi-robot system coordination state space formation maneuver subgoal

High frequency S wave envelope synthesis using a multiple non-isotropic scattering model: application to aftershocks from the 2008 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 185-194页

作者： Lin Gao Jing Yueling Li jianbo The State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Earthquake Engineering Research Division Dalian University of Technology

Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the initial intensity spectral density of a seismic wave is incorporated into the integral equation of seismic wave energy density. And, a recursive formula of Green＇s function is derived to obtain the higher order Green＇s function, which is included to describe the stronger non-isotropic scattering process. Then, the effect of the scattering pattern on the energy density envelope is investigated by the modified scattering theory. Significant differences arc found in the decay of the energy density envelopes with distances using different scattering patterns. The envelope synthesized by the forward dominated scattering pattern is larger than the results obtained by the isotropic and backward dominated scattering pattern. Different scattering patterns are also used to fit the observation data from the aftershocks of the 2008 Wenchuan earthquake. It is concluded that the envelopes synthesized by the forward scattering pattern can match the data better than the isotropic and backward dominated scattering cases, and a new interpretation of the coda wave is given. Finally, using the forward dominated scattering pattern, the envelope broadening of the observed data is reproduced.

关键词： non-isotropic scattering coda wave envelope broadening energy transport theory (radiative transfer theory) directional scattering coefficient ground motion

First Principles Study of Structural Stability and Magnetic Property of Non-equilibrium Co–Mo Alloys

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1057-1062页

作者： Shunning Li Baixin Liu jianbo Liu Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University

First principles calculations are carried out to investigate the structural stability of several non-equilibrium intermetallic phases in the cobalt（Co）–Mo system using spin polarized projected augmented-wave potentials. It is revealed that the Co3Mo, CoMo, and CoMo3 alloys are energetically favored to be in D019, B11, and A15 structures, respectively,and that the magnetic moments of Co atoms would decrease rapidly with an increasing percentage of Mo content and would most probably disappear when the content of Mo is no less than 50 at%. Generally, the calculated results in the present work match well with the available experimental observations.

关键词： First principles calculation Transition metals Cobalt Magnetic property Electronic structure

Cooperative guidance of seeker-less missile considering localization error

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Chinese Journal of Aeronautics 2019年第8期32卷 1933-1945页

作者： jianbo ZHAO Shuxing YANG Fenfen XIONG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Xi’an Modern Control and Technology Institute Xi’an 710065China

To perform an accurate fire-and-forget attack of seeker-less missile with the consideration of the localization error, a new cooperative guidance strategy of multi-missiles is proposed in this work. Firstly, an estimated position of the seeker-less missile is carefully selected, based on which the slant angle of the line between the estimated and real positions of the seeker-less missile is approximately derived inspired by the localization theory of GPS(Global Position System).Then, respectively based on the guidance law considering the impact angle and time constraints, the consensus theory and the finite-time convergence approach, three cooperative guidance laws employing the previously obtained slant angle are derived for intensive attack to address either a stationary or maneuvering target. Simulation results well demonstrate the effectiveness and advantages of the proposed cooperative guidance strategy.

关键词： Cooperative guidance Fire-and-forget Intensive attack Localization error Missile guidance Seeker-less

Review of characterization and modeling of polymer electrolyte fuel cell catalyst layer： The blessing and curse of ionomer

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Frontiers in Energy 2017年第3期11卷 334-364页

作者： Jun HUANG Zhe LI jianbo ZHANG Department of Automotive Engineering State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Beijing Co-innovation Center for Electric Vehicles Beijing Institute of Technology Beijing 100081 China

Ionomer impregnation represents a milestone in the evolution of polymer electrolyte fuel cell （PEFC） catalyst layers. Ionomer acts as the binder, facilitates proton transport, and thereby drastically improves catalyst utilization and effectiveness. However, advanced morpho- logical and functional characterizations have revealed that up to 60% of Pt nanoparticles can be trapped in the micropores of carbon support particles. Ionomer clusters and oxygen molecules can hardly enter into micropores, leading to low Pt utilization and effectiveness. Moreover, the ionomer thin-films covering Pt nanoparticles can cause significant mass transport loss especially at high current densities. Ionomer-free ultra-thin catalyst layers （UTCLs） emerge as a promising alternative to reduce Pt loading by improving catalyst utilization and effectiveness, while theoretical issues such as the proton conduction mechan- ism remain puzzling and practical issues such as the rather narrow operation window remain unsettled. At present, the development of PEFC catalyst layer has come to a crossroads： staying ionomer-impregnated or going iono- mer-free. It is always beneficial to look back into the past when coming to a crossroads. This paper addresses the characterization and modeling of both the conventional ionomer-impregnated catalyst layer and the emerging ionomer-free UTCLs, featuring advances in characterizing microscale distributions of Pt particles, ionomer, support particles and unraveling their interactions; advances in fundamental understandings of proton conduction and flooding behaviors in ionomer-free UTCLs; advances in modeling of conventional catalyst layers and especially UTCLs; and discussions on high-impact research topics in characterizing and modeling of catalyst layers.

关键词： polymer electrolyte fuel cell ultra-thin cata-lyst layer electrostatic interactions characterization andmodeling structure-property-performance relation watermanagement

Dynamic interaction numerical models in the time domain based on the high performance scaled boundary finite element method

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 541-546页

作者： Li jianbo Liu Jun Lin Gao The State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Institute of Earthquake Engineering School of Hydraulic EngineeringDalian University of Technology

Consideration of structure-foundation-soil dynamic interaction is a basic requirement in the evaluation of the seismic safety of nuclear power facilities. An efficient and accurate dynamic interaction numerical model in the time domain has become an important topic of current research. In this study, the scaled boundary finite element method （SBFEM） is improved for use as an effective numerical approach with good application prospects. This method has several advantages, including dimensionality reduction, accuracy of the radial analytical solution, and unlike other boundary element methods, it does not require a fundamental solution. This study focuses on establishing a high performance scaled boundary finite element interaction analysis model in the time domain based on the acceleration unit-impulse response matrix, in which several new solution techniques, such as a dimensionless method to solve the interaction force, are applied to improve the numerical stability of the actual soil parameters and reduce the amount of calculation. Finally, the feasibility of the time domain methods are illustrated by the response of the nuclear power structure and the accuracy of the algorithms are dynamically verified by comparison with the refinement of a large-scale viscoelastic soil model.

关键词： time domain analysis dynamic interaction acceleration impulse response function scaled boundary finiteelement method viscoelastic boundary

Biogenic volatile organic compound analyses by PTR-TOF-MS: Calibration, humidity effect and reduced electric field dependency

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Journal of Environmental Sciences 2015年第6期27卷 196-206页

作者： Xiaobing pang Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and Technology

Green leaf volatiles（GLVs） emitted by plants after stress or damage induction are a major part of biogenic volatile organic compounds（BVOCs）. Proton transfer reaction time-of-flight mass spectrometry（PTR-TOF-MS） is a high-resolution and sensitive technique for in situ GLV analyses, while its performance is dramatically influenced by humidity, electric field,etc. In this study the influence of gas humidity and the effect of reduced field（E/N） were examined in addition to measuring calibration curves for the GLVs. Calibration curves measured for seven of the GLVs in dry air were linear, with sensitivities ranging from 5 to10 ncps/ppbv（normalized counts per second/parts per billion by volume）. The sensitivities for most GLV analyses were found to increase by between 20% and 35% when the humidity of the sample gas was raised from 0% to 70% relative humidity（RH） at 21°C, with the exception of（E）-2-hexenol. Product ion branching ratios were also affected by humidity,with the relative abundance of the protonated molecular ions and higher mass fragment ions increasing with humidity. The effect of reduced field（E/N） on the fragmentation of GLVs was examined in the drift tube of the PTR-TOF-MS. The structurally similar GLVs are acutely susceptible to fragmentation following ionization and the fragmentation patterns are highly dependent on E/N. Overall the measured fragmentation patterns contain sufficient information to permit at least partial separation and identification of the isomeric GLVs by looking at differences in their fragmentation patterns at high and low E/N.

关键词： Biogenic volatile organic compound PTR-TOF-MS Humidity effect Reduced electric field

A New Cluster Updating for 2-D SU(2)×SU(2) Chiral Model

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Chinese Physics Letters 1993年第9期10卷 554-557页

作者： ZHANG jianbo JI Daren Zhejiang Institute of Modern Physics Zhejiang UniversityHangzhou 310027

We propose a variant version of Wolffs cluster algorithm,which may be extended to SU(N)×SU(N)dural model,and test it in 2-diniensiontil SU(2)×SU(2)chiral *** results show that the new method can efficiently reduce t... 详细信息

关键词： SU(2) model. chiral

Molecular mechanism and research progress of traditional Chinese medicine in the treatment of prostate cancer

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Traditional Medicine Research 2025年第1期10卷 62-72页

作者： Hai-Luo Wang Ruo-Ran Zhang Hao Wang Peng Xu Jing-Kai Wang Bo Chen Hao Xu Deng Pan Yu-Yang Ma Kun pang Department of Urology Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical CollegeXuzhou 221009China Graduate School Jiangsu UniversityZhenjiang 212013China Graduate School Bengbu Medical UniversityBengbu 233040China Department of Urology The Peixian People’s HospitalXuzhou 221699China.

Prostate cancer(PCa)is one of the most common malignant tumors in the male genitourinary system,ranking second in incidence *** Chinese medicine(TCM),as an important component of complementary and alternative medicine,shows unique advantages in cancer *** herbal medicine is usually composed of multiple ingredients and involves multiple signaling pathways,which showed function of inducing apoptosis of cancer cells,arresting the cell cycle,inhibiting invasion and metastasis,reducing drug resistance,and regulating immune *** therapy is also an important treatment of ***,Physical therapy such as acupuncture or Tai Chi and Qigong are gaining increased recognition in the management of PCa,particularly in addressing issues like urinary incontinence and bone metastasis-related *** article reviews the TCM treatment and therapy of PCa,in order to provide new research avenues and treatment options for the treatment of PCa with TCM and improve the quality of life of patients.

关键词： traditional Chinese medicine prostate cancer Chinese herbal medicine physical therapy