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New upper limit on the cosmological constant from solar system dynamics

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Research in Astronomy and Astrophysics 2014年第5期14卷 527-532页

作者： shuang liang Yi Xie School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

The cosmological constant A is the simplest model for explaining the dark energy which supposedly drives the observed accelerated expansion rate of the Universe. Together with the concept of cold dark matter, it satisfactorily accommo- dates a wealth of observations related to cosmology. Due to its assumed constancy throughout the Universe, A might also affect the dynamics of the planets in the so- lar system, although with extremely small effects. However, modern high-precision ephemerides provide a promising tool for constraining it. Using the supplementary advances in the perihelia provided by current INPOP10a and EPM2011 ephemerides, we obtain a new upper limit on A in the solar system when the Lense-Thirring ef- fect due to the Sun＇s angular momentum and the uncertainty of the Sun＇s quadrupole moment are properly taken into account. These two factors were mostly absent in pre- vious works dealing with A. We find that INPOP10a yields an upper limit of A = （0.26±1.45） × 10^-43 m^-2 and EPM2011 gives A = （-0.44 4±8.93） × 10^-43 m^-2. Such bounds are about 10 times less than previously estimated results.

关键词： cosmology theory -- celestial mechanics -- ephemerides -- relativity

Model of a Composite Energy Storage System for Urban Rail Trains

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Computer Systems Science & Engineering 2022年第3期40卷 1145-1152页

作者： liang Jin Qinghui Meng shuang liang Department of Mechanical and Electrical Henan Polytechnic InstituteNanyang473000China University of Florence Firenze50041Italy

Urban rail transit can solve the current inconvenient transportation problem for China’s large urban population.A compound onboard energy storage system can meet vehicles’traction requirements and recover energy in vehicles’braking stage to improve energy ***,the composite onboard energy storage system has several concerns,such as its power and energy demand,battery aging,and maintenance ***,the NSGA-II algorithm is proposed to optimise matching the composite energy storage system parameters for urban rail *** NSGA-II algorithm was used with an improved elite retention strategy to optimise the parameters matching of the composite power *** optimisation’s objective concerns the replacement costs and economy of the composite power *** method increases the vertical diversity of searching and avoids genetic *** NSGA-II algorithm calls the simulation model of composite power supply in real-time and simultaneously optimises the composite power supply and control *** Pareto set of optimisation objectives and corresponding parameters and control strategies of composite power supply are *** NSGA-II algorithm can optimise the composite energy storage system’s parameters and improve the train and the composite power supply’s performance *** algorithm greatly reduces the composite power supply’s capacitance and reduces the system’s total energy ***,the multi-component energy loss caused by the multi-power source system can be effectively *** total capacitance is reduced by 12.1%,the battery life is prolonged by 18.86%,and the optimised composite power supply’s energy storage is increased by 17.6%.

关键词： Manuscript preparation typeset format

Operation Optimal Control of Urban Rail Train Based on Multi-Objective Particle Swarm Optimization

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Computer Systems Science & Engineering 2022年第7期42卷 387-395页

作者： liang Jin Qinghui Meng shuang liang Department of Mechanical and Electrical Henan Polytechnic InstituteNanyang Henan473000China University of Florence Firenze50041Italy

The energy consumption of train operation occupies a large proportion of the total consumption of railway *** order to improve the oper-ating energy utilization rate of trains,a multi-objective particle swarm optimiza-tion(MPSO)algorithm with energy consumption,punctuality and parking accuracy as the objective and safety as the constraint is *** accelerate its the convergence process,the train operation progression is divided into several modes according to the train speed-distance curve.A human-computer interactive particle swarm optimization algorithm is proposed,which presents the optimized results after a certain number of iterations to the decision maker,and the satisfac-tory outcomes can be obtained after a limited number of *** multi-objective particle swarm optimization(MPSO)algorithm is used to optimize the train operation *** algorithm based on the important relationship between the objective and the preference information of the given reference points is sug-gested to overcome the shortcomings of the existing *** methods signiﬁcantly increase the computational complexity and convergence of the *** adaptive fuzzy logic system that can simultaneously utilize experience information andﬁeld data information is proposed to adjust the consequences of off-line optimization in real time,thereby eliminating the inﬂuence of uncertainty on train *** optimization and adjustment,the whole running time has been increased by 0.5 s,the energy consumption has been reduced by 12%,the parking accuracy has been increased by 8%,and the comprehensive performance has been enhanced.

关键词： Particle swarm optimization multi-objective urban rail train optimal control

Response of Bi-disperse Polyelectrolyte Brushes to External Electric Fields A Numerical Self-consistent Field Theory Study

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Chinese Journal of Polymer Science 2017年第1期35卷 98-107页

作者： Cong Kang shuang-liang Zhao 童朝晖 Department of Physics Ningbo University Ningbo 315211 China College of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

The self-consistent field theory has been employed to numerically study the response of bi-disperse flexible polyelectrolyte （PE） brushes grafted on an electrode to electric fields generated by opposite surface charges on the PE-grafted electrode and a second parallel electrode. The numerical study reveals that, under a positive external electric field, the shorter and negatively charged PE chains are more responsive than the longer PE chains in terms of the relative changes in their respective brush heights. Whereas under a negative external electric field, the opposite was observed. The total electric force on the grafted PE chains was calculated and it was found that, under a positive external electric field, the magnitude of the total electric force acting on one shorter PE chain is larger than that on one longer PE chain, or vice versa. The underlying mechanism was unraveled through analyzing the total electric field across the two oppositely charged electrodes.

关键词： Polyelectrolyte brushes Self-consistent field theory Electrical stimulus Polydispersity

State transitions triggered by inverse magnetic field: probably applied in high-mass X-ray binaries?

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Research in Astronomy and Astrophysics 2016年第3期16卷 107-110页

作者： shuang-liang Li Zhen Yan Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

Previous works suggested that the state transitions in an X-ray binary can be triggered by accret- ing an inverse magnetic field from its companion star. A key point of this mechanism is the accretion and magnification of large-scale magnetic fields from the outer boundary of a thin disk. However, how such a process can be realized is still an open question. In this work, we check this issue in a realistic X-ray binary system. According to our calculations, a quite strong initial magnetic field, B - 10^2 - 10^3 G, is required in order to assure that the large-scale magnetic field can be effectively dragged inward and magnified with the accretion of gas. Thus, such a picture probably can be present in high-mass X-ray binaries possessing a strong stellar magnetic field, e.g., Cyg X-1.

关键词： accretion accretion disks-- blackhole physics-- (magnetohydrodynamics)MHD--X-rays binaries

Regularity for anisotropic solutions to some nonlinear elliptic system

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Frontiers of Mathematics in China 2016年第1期11卷 77-87页

作者： Hongya GAO shuang liang Yi CUI College of Mathematics and Information Science Hebei University Baoding 071002 China

Abstract This paper deals with anisotropic solutions u∈W1,（pi）（Ω,RN）to-n∑i=1Di（aα/i（x,Du（x）））=-n∑i=1DiFα/i（x）,α=1,2...,*** present a rnonotonicity inequality for the matrix a=（aα/i）∈Rn×n,whichg... 详细信息

关键词： Regularity anisotropic solution nonlinear elliptic system

Predictive Control Algorithm for Urban Rail Train Brake Control System Based on T-S Fuzzy Model

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Computers, Materials & Continua 2020年第9期64卷 1859-1867页

作者： Xiaokan Wang Qiong Wang shuang liang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China Henan Mechanical and Electrical Vocational College Xinzheng451191China University of Florence Via Sandro PertiniFirenze50041Italy

Urban rail transit has the advantages of large traffic capacity,high punctuality and zero congestion,and it plays an increasingly important role in modern urban *** system is an important system of urban rail train,which directly affects the performance and safety of train operation and impacts passenger *** braking performance of urban rail trains is directly related to the improvement of train speed and transportation ***,urban rail transit has the characteristics of high speed,short station distance,frequent starting,and frequent *** makes the braking control system constitute a time-varying,time-delaying and nonlinear control system,especially the braking force changes directly disturb the parking accuracy and *** solve these issues,a predictive control algorithm based on T-S fuzzy model was proposed and applied to the train braking control *** with the traditional PID control algorithm and self-adaptive fuzzy PID control algorithm,the braking capacity of urban rail train was improved by 8%.The algorithm can achieve fast and accurate synchronous braking,thereby overcoming the dynamic influence of the uncertainty,hysteresis and time-varying factors of the controlled ***,the desired control objectives can be achieved,the system will have superior robustness,stability and comfort.

关键词： Predictive control T-S fuzzy model urban rail train algorithm

Employment Quality EvaluationModel Based on Hybrid Intelligent Algorithm

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Computers, Materials & Continua 2023年第1期74卷 131-139页

作者： Xianhui Gu Xiaokan Wang shuang liang Henan Mechanical Electrical Vocational College Xinzheng Hennan451191China University of Florence Firenze50041Italy

In order to solve the defect of large error in current employment quality evaluation,an employment quality evaluation model based on grey correlation degree method and fuzzy C-means(FCM)is ***,it analyzes the related research work of employment quality evaluation,establishes the employment quality evaluation index system,collects the index data,and normalizes the index data;Then,the weight value of employment quality evaluation index is determined by Grey relational analysis method,and some unimportant indexes are removed;Finally,the employment quality evaluation model is established by using fuzzy cluster analysis algorithm,and compared with other employment quality evaluation *** test results show that the employment quality evaluation accuracy of the design model exceeds 93%,the employment quality evaluation error can meet the requirements of practical application,and the employment quality evaluation effect is much better than the comparison *** comparison test verifies the superiority of the model.

关键词： Employment quality fuzzy c-means clustering algorithm grey correlation analysis method evaluation model index system comparative test

Structural controllability of Boolean control networks with an unknown function structure

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Science China(Information Sciences) 2020年第11期63卷 321-323页

作者： shuang liang Haitao LI Shuling WANG School of Mathematics and Statistics Shandong Normal University

Dear editor,Boolean networks represent one of the most popular models for gene regulatory networks. In a Boolean network, genes are perceived as nodes in a network graph, and the dynamics of each node are determined b... 详细信息

关键词： Boolean control network Structural controllability Algebraic state space representation Semi-tensor product Gene regulatory network