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Calculations of electric quadrupole moments and charge radii for high-K isomers

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2037-2041页

作者： liu hongliang XU FuRong Department of Applied Physics School of ScienceXi'an Jiaotong University State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University

Configuration-constrained potential-energy-surface calculations are performed to investigate high-K isomers in97Y,130Ba,176Yb,177Lu,and178Hf that were observed to have increased electric quadrupole moments but decreased charge radii relative to the states on which they are *** into account the efects of deformation change and unpaired protons,our calculations can reproduce the enhancement of electric quadrupole moments for the isomers in97Y,130Ba,176Yb,177Lu and the Kπ=8 isomer in178Hf,and can reproduce the reduction of charge radii for the Kπ=27/2 isomer in97Y and the Kπ=16+isomer in178Hf.

关键词： high-K isomer electric quadrupole moment charge radius

An Effective Feature Modeling Approach for 3D Structural Topology Design Optimization

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Computer Modeling in Engineering & Sciences 2021年第4期127卷 43-57页

作者： Fusheng Qiu hongliang liu Hongjuan Zhao College of Aerospace Engineering Shenyang Aerospace UniversityShenyang110136China Chengdu Aircraft Industrial(Group)Co. Ltd.Chengdu610092China

This paper presents a feature modeling approach to address the 3D structural topology design optimization withfeature constraints. In the proposed algorithm, various features are formed into searchable shape features bythe feature modeling technology, and the models of feature elements are established. The feature elements thatmeet the design requirements are found by employing a feature matching technology, and the constraint factorscombined with the pseudo density of elements are initialized according to the optimized feature elements. Then,through controlling the constraint factors and utilizing the optimization criterion method along with the filteringtechnology of independent mesh, the structural design optimization is implemented. The present feature modelingapproach is applied to the feature-based structural topology optimization using empirical data. Meanwhile, theimproved mathematical model based on the density method with the constraint factors and the correspondingsolution processes are also presented. Compared with the traditional method which requires complicated constraintprocessing, the present approach is flexibly applied to the 3D structural design optimization with added holesby changing the constraint factors, thus it can design a structure with predetermined features more directly andeasily. Numerical examples show effectiveness of the proposed feature modeling approach, which is suitable for thepractical engineering design.

关键词： Topology optimization feature modeling feature constraint constraint factor density method

Improved descriptions of collective and non-collective rotations in the superheavy nucleus ^(256)Rf

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Chinese Science Bulletin 2014年第1期59卷 11-15页

作者： hongliang liu Furong Xu Department of Applied Physics School of Science Xi’an Jiaotong University State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University

The superheavy nucleus256Rf,where rotational band and multi-quasiparticle isomer have been observed recently,has been investigated using total Routhian surface calculations and configuration-constrained calculations of potential energy surface,with the inclusion of *** experimental moment of inertial is well reproduced,indicating that the alignment is delayed due to the b6deformation.A K p=5-or 8-state could form a two-quasiparticle isomer that is calculated to have higher fission barrier than the ground state.

关键词：超重核集体异构体准粒子转动带计算势能面位能面

Linearization threshold condition and stability analysis of a stochastic dynamic model of one-machine infinite-bus (OMIB) power systems

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Protection and Control of Modern Power Systems 2021年第1期6卷 242-252页

作者： Lijuan Li Yongdong Chen Bin Zhou hongliang liu Yongfei liu College of Automation and Electronic Information Hunan Engineering Research Center of Multi energy Cooperative Control TechnologyXiangtan UniversityXiangtan411105China College of Automation and Electronic Information Xiangtan UniversityXiangtan411105China College of Electrical and Information Engineering Hunan UniversityChangsha410082China College of Mathematics and Computational Science Xiangtan UniversityXiangtan411105China State Grid Jiangsu Electric Power Co.Electric Power Research Institute Nanjing210000China

With the increase in the proportion of multiple renewable energy sources, power electronics equipment and new loads, power systems are gradually evolving towards the integration of multi-energy, multi-network and multi-subject affected by more stochastic excitation with greater intensity. There is a problem of establishing an effective stochastic dynamic model and algorithm under different stochastic excitation intensities. A Milstein-Euler predictor-corrector method for a nonlinear and linearized stochastic dynamic model of a power system is constructed to numerically discretize the models. The optimal threshold model of stochastic excitation intensity for linearizing the nonlinear stochastic dynamic model is proposed to obtain the corresponding linearization threshold condition. The simulation results of one-machine infinite-bus (OMIB) systems show the correctness and rationality of the predictor-corrector method and the linearization threshold condition for the power system stochastic dynamic model. This study provides a reference for stochastic modelling and efficient simulation of power systems with multiple stochastic excitations and has important application value for stability judgment and security evaluation.

关键词： Power system stability Stochastic dynamic model Stochastic excitation Stochastic processes Threshold condition

Legendre Neural Network for Solving Linear Variable Coefficients Delay Differential-Algebraic Equations with Weak Discontinuities

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Advances in Applied Mathematics and Mechanics 2021年第1期13卷 101-118页

作者： hongliang liu Jingwen Song Huini liu Jie Xu Lijuan Li School of Mathematics and Computational Science&Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan UniversityXiangtanHunan 411105China School of Automation and Electronic Information Xiangtan UniversityXiangtanHunan 411105China

In this paper,we propose a novel Legendre neural network combined with the extreme learning machine algorithm to solve variable coefficients linear delay differential-algebraic equations with weak ***,the solution interval is divided into multiple subintervals by weak discontinuity ***,Legendre neural network is used to eliminate the hidden layer by expanding the input pattern using Legendre polynomials on each ***,the parameters of the neural network are obtained by training with the extreme learning *** numerical examples show that the proposed method can effectively deal with the difficulty of numerical simulation caused by the discontinuities.

关键词： Convergence delay differential-algebraic equations Legendre activation function,neural network.

Effect of Rare Earth Elements on Transformation Behavior and Microstructure Characteristics in X80 Pipeline Steel

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稀有金属材料与工程 2011年第S3期40卷 51-55页

作者： liu Chengjun, liu hongliang, Jiang Maofa Northeastern University, Shengyang 110004, China Northeastern Univ Sch Met & Mat Shenyang 110004 Peoples R China

The studies of the rare earth elements (RE) in low carbon steels suggest that the RE inhibits the ferrite transformation, which is the same effect as Mo alloying in pipeline steels. The purpose of this work is to discuss the relationships between the RE microalloying and the microstructure in pipeline steels. The X80 pipeline steels with different RE and Mo additions have been produced by vacuum induction furnace. The Gleeble-2000 thermal simulator, optical microscopy, and scanning electron microscopy with EBSD have been used. The continuous cooling transformation (CCT) curve was obtained and analyzed, combined with the study of microstructure. The results indicate that the microstructure of thermal simulator test metal is characteristic of quasi-polygonal ferrite and bainite, and trace RE could significantly inhibit the transformation of quasi-polygonal ferrite. The 0.0040wt% content of RE plays the same role as 0.1 wt% content of Mo alloying in pipeline steels. What’s more, the fine bainite grained structure is obtained with RE microalloying. Theoretically RE could be employed in pipeline steels as microalloying, and a partial substitution of Mo by RE is possible.

关键词： rare earth elements pipeline steel transformation microstructure CCT

A model and experimental study of phosphate uptake kinetics in algae:Considering surface adsorption and P-stress

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Journal of Environmental Sciences 2011年第2期23卷 189-198页

作者： Bo Yao Beidou Xi Chunming Hu Shouliang Huo Jing Su hongliang liu School of Environment Beijing Normal University Beijing 100875 China Chinese Research Academy of Environmental Sciences Beijing 100012 China College of Life Science Northeast Agriculture University Harbin 150030 China

Phosphorus is an important limiting nutrient in many ecosystems. Consequently, there is increasing interest on phosphate uptake and algal growth due to the increasing frequency and magnitude of algal blooms induced by eutrophication. The co-existence of surface adsorbed and intracellular phosphorus pools indicate that phosphate uptake by phytoplankton is, to some extent, a two-stage kinetic process. However, almost all previous uptake models considered the internal uptake stage only and ignored the possible impact of surface adsorption. In this article, a two-stage kinetic uptake model considering both surface adsorption and P-stress on phosphate uptake by algae was constructed and compared to conventional one-stage models, based on experimental data on short-term uptake kinetics of a green algae S. quadricauda. Results indicated that with suitable parameters, the two-stage uptake model not only fit the experimental data better, but also gave more reasonable and realistic explanations to the phosphate uptake process. The results are meaningful as surface-adsorption of phosphate may affect the uptake process of phosphate and assist in understanding realistic phosphate uptake kinetics in phytoplankton.

关键词： phosnhate uotake surface adsorption P-starvation nhvtoplankton

Stability and Convergence of the Canonical Euler Splitting Method for Nonlinear Composite Stiff Functional Differential-Algebraic Equations

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Advances in Applied Mathematics and Mechanics 2022年第6期14卷 1276-1301页

作者： hongliang liu Yameng Zhang Haodong Li Shoufu Li School of Mathematics and Computational Science&Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan UniversityXiangtanHunan 411105China

A novel canonical Euler splitting method is proposed for nonlinear compositestiff functional differential-algebraic equations, the stability and convergence of themethod is evidenced, theoretical results are further confirmed by some numerical ***, the numerical method and its theories can be applied to specialcases, such as delay differential-algebraic equations and integral differential-algebraicequations.

关键词： Canonical Euler splitting method nonlinear composite stiff functional differentialalgebraic equations stability convergence.

Topology Optimization for Harmonic Excitation Structures with Minimum Length Scale Control Using the Discrete Variable Method

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 1941-1964页

作者： hongliang liu Peijin Wang Yuan Liang Kai Long Dixiong Yang Key Laboratory of Liaoning Province for Composite Structural Analysis of Aerocraft and Simulation College of Aerospace EngineeringShenyang Aerospace UniversityShenyang110136China State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian116023China State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206China

Continuumtopology optimization considering the vibration response is of great value in the engineering structure *** aimof this studyis toaddress the topological designoptimizationof harmonic excitationstructureswith minimumlength scale control to facilitate *** topology design based on discrete variables is proposed to avoid localized vibration modes,gray regions and fuzzy boundaries in harmonic excitation topology *** topological design model and sensitivity formulation are *** requirement of minimum size control is transformed into a geometric constraint using the discrete ***,thin bars,small holes,and sharp corners,which are not conducive to the manufacturing process,can be eliminated from the design *** present optimization design can efficiently achieve a 0–1 topology configuration with a significantly improved resonance frequency in a wide range of excitation ***,the optimal solution for harmonic excitation topology optimization is not necessarily symmetric when the load and support are symmetric,which is a distinct difference fromthe static optimization ***,one-half of the design domain cannot be selected according to the load and support *** examples are presented to demonstrate the effectiveness of the discrete variable design for excitation frequency topology optimization,and to improve the design manufacturability.

关键词： Discrete variable topology optimization harmonic excitation minimumlength scale control geometric constraint manufacturability