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Spectrum of Normal Weighted Composition Operators on the Fock Space Over C^N

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Acta Mathematica Sinica,English Series 2019年第9期35卷 1563-1572页

作者： Li Xia FENG lian Kuo zhao School of Mathematics and Computer Science Shanxi Normal University

By using commutative C*-algebra techniques, spectrum and essential spectrum of normal weighted composition operators on the Fock space over CN are completely characterized. As an application, spectrum of self-adjoint ... 详细信息

关键词： Fock space weigh ted composition operator normal spectrum

Observability of Periodically Switched Boolean Control Networks

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Journal of Systems Science & Complexity 2023年第3期36卷 985-1001页

作者： JIANG Chunfeng WANG biao FU Shihua zhao Jianli SUN Min Department of Engineering University of SannioBenevento 82100Italy.Email:chunf jiang@*** School of Management Shandong UniversityJinan 250100China School of Mathematical Sciences Liaocheng UniversityLiaocheng 252000China School of Mathematics and Statistics Zaozhuang UniversityZaozhuang 277160China

In this paper,observability is studied for periodically switched Boolean control networks(PSBCNs),which are managed with periodic switching signal and consist of some Boolean control ***,via semi-tensor product of matrices,PSBCNs are expressed as algebraic ***,a parallel system is constructed by combining two same PSBCNs,based on which,the observability problem of the original PSBCN can be transformed into the set reachability problem of this parallel ***,two necessary and sufficient conditions are obtained to detect reachability of parallel systems and observability of *** addition,the proposed conditions are extended to the case of state ***,a practical example and a numerical example are provided to illustrate the results.

关键词： Boolean control networks observability periodically switched systems semi-tensor product state constraints

An efficient hyper-elastic model for the preforming simulation of Carbon-Kevlar hybrid woven reinforcement

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Chinese Journal of Aeronautics 2022年第12期35卷 321-335页

作者： Sasa GAO Zhengtao QU Yunjie ZHANG Zizhao zhao biao lianG College of Mechanical&Electrical Engineering Shaanxi University of Science&TechnologyXi’an 710021China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

An efficient hyper-elastic model that can reflect the primary mechanical behaviors of Carbon-Kevlar hybrid woven reinforcement was developed and implemented with VUMAT constitutive code for preforming *** model parameters were accurately determined through the uniaxial and bias-extension *** calibrate the simulation code,preforming experiments of hybrid woven reinforcement over the hemisphere mold and tetrahedron mold were respectively conducted to validate the proposed hyper-elastic *** comparison between the simulations and experiments shows that the model can not only accurately capture shear angle distribution and geometry shape after deformation,but also accurately predict the force–displacement curve and potential fiber tensile failure during the preforming *** result indicates that the proposed model can be used to predict the preforming behavior of Carbon-Kevlar hybrid woven reinforcement,and simulate its manufacturing process of complicated geometry.

关键词： Constitutive law Finite element analysis Hybrid woven reinforcement Hyper-elastic Preforming

On the L_p-Dual Mixed Volumes

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1647-1654页

作者： lian Ying CHEN Chang Jian zhao Department of Mathematics China Jiliang University

We establish the cyclic inequality for i-th L p-dual mixed volume and Lp-dual Urysohn inequality between p-mean width and Lp-dual quermassintegral. Moreover, the dual isoperimetric inequality for Lp-dual mixed volume ... 详细信息

关键词： Dual mixed volume Lp-dual mixed volume mean width Lp-mean width dual isoperi-metric inequality Lp-dual quermassintegral

Farmers’Character and Behavior of Fertilizer Application-Evidence from a Survey of Xinxiang County,Henan Province,China

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Agricultural Sciences in China 2009年第10期8卷 1238-1245页

作者： HAN Hong-yun zhao lian-ge Center for Agricultural and Rural Development Zhejiang University Hangzhou 310029 P.R.China College of Economics Zhejiang Gongshang University Hangzhou 310035 P.R. China

Agricultural chemical use has caused a public concern over environmental issue while decisions about applying chemicals are made by individual farmers. The critical decision-making role of farmers relative to agricultural chemical use creates a need for accurate information on their perceptions of various chemical-related hazards and the factors that may influence such judgments. Based on data collected from 177 land operators at Xinxiang County in Henan Province of China, an empirical analysis is conducted to examine the relationship between farmers＇ character and the behavior of fertilizer application. Study findings reveal that： the characteristics of household head and household, and the nature of farming management positively affect the amount of fertilizers applied; information on fertilizers and the knowledge about environmental impact of fertilizer application have negative impacts by contrast. To formulate effective pollution control policies at the farm level, it is imperative for policy-makers to convey information to producers by demonstration projects, technical assistance, and education programs. Under a changed political environment, some combination of education and economic incentives could be lower cost and more effective tools for achieving desired environmental conservative goals.

关键词： nonpoint-pollution farmers' decision fertilizer application

The effects of the non-breaking surface wave-induced vertical mixing on the forecast of tropical cyclone tracks

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Chinese Science Bulletin 2014年第24期59卷 3075-3084页

作者： biao zhao Fangli Qiao Guansuo Wang First Institute of Oceanography State Oceanic Administration

The Weather Research and Forecasting model(WRF)is configured for the region of(15°–41°N,105°–135°E),which covers the same area with the MASNUM(Key *** Science&Numerical Modeling,State Oceanic Administration)wave-tide-circulation coupled operational forecast *** numerical experiments are implemented to investigate the effects of the real-time forecasted sea surface temperature(SST)and the nonbreaking wave-induced vertical mixing(Bv)on the track forecast of all 33 tropical cyclones(TC)in the model domain area during 2008 and *** first experiment employs NCEP FNL(NCEP final analysis)SST as WRF’s bottom condition as the Control run,which is also the default setup of *** second and third experiments use real-time forecasted SST from the MASNUM forecast system with and without Bv,*** forecasted track results are compared with Japan Meteorological Agency’s best track *** 24-h forecast,the averaged TC position error of Experiment with Bv is reduced by 9%compared to the Control experiment,while the forecasted track error of Experiment without Bv is reduced by only2%compared to the Control *** the 48-h forecast,the averaged track errors are reduced by 10%and6%with Bv and without Bv compared to the Control experiment,*** results suggest that the real-time forecasted SST can improve the performance of WRF in forecasting TC track,and the Bv plays an important role in reducing the forecast error of TC ***,Bv can improve more on the track of stronger TC.

关键词：热带气旋路径预报垂直混合重点实验室 WRF模式实时预测面波数值试验最佳轨道

Space-Curved Resonant Line Solitons in a Generalized (2+1)-Dimensional Fifth-Order KdV System

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Chinese Physics Letters 2021年第6期38卷 13-17页

作者： Zequn Qi zhao Zhang biao Li School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

On the basis of N-soliton solutions,space-curved resonant line solitons are derived via a new constraint proposed here,for a generalized (2+1)-dimensional fifth-order KdV *** dynamic properties of these new resonant line solitons are studied in *** then discuss the interaction between a resonance line soliton and a lump wave in greater *** results highlight the distinctions between the generalized (2+1)-dimensional fifth-order KdV system and the classical type.

关键词： soliton resonant solitons

掺杂对TiC_(2)纳米片析氢反应的第一性原理研究

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原子与分子物理学报 2025年第3期42卷 29-34页

作者：孙楠楠赵翠莲潘美玲赵志超张宇河北水利电力学院基础部沧州061000 河北省数据中心相变热管理技术创新中心沧州061000

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明... 详细信息

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明,在高氢覆盖率内,O和V掺杂能有效的降低氢吸附的吉布斯自由能.低密度掺杂可以提高催化能力.我们进一步研究表明,由于V原子在二碳化钛(TiC_(2))单层中具有最低的负形成能,因此比其他过渡金属原子更容易取代Ti原子.期望掺钒TiC_(2)单分子膜能以更高的效率应用于水电解.

关键词：密度泛函理论 TiC_(2)单层片覆盖率掺杂

维普期刊数据库博看期刊

Upper bound solution of supporting pressure for a shallow square tunnel based on the Hoek-Brown failure criterion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第4期13卷 284-292页

作者： Fu HUANG Xiao-li YANG lian-heng zhao School of Civil Engineering Central South UniversityChangsha 410075China

To analyze the stability of a shallow square tunnel, a new curved failure mechanism, representing the mechanical characteristics and collapsing form of this type of tunnel, is constructed. Based on the upper bound theorem of limit analysis and the Hoek-Brown nonlinear failure criterion, the supporting pressure derived from the virtual work rate equation is regarded as an objective function to achieve optimal calculation. By employing variational calculation to optimize the objective function, an upper bound solution for the supporting pressure and the collapsing block shape of a shallow square tunnel are obtained. To evaluate the validity of the failure mechanism proposed in this paper, the solutions computed by the curved failure mechanism are compared with the results calculated by the linear multiple blocks failure mechanism when the Hoek-Brown nonlinear failure criterion is converted into the Mohr-Coulomb linear criterion. The influences of rock mass parameters on the supporting pressure and collapsing block shape are discussed.

关键词： Shallow square tunnel Variational calculation Curved failure mechanism Supporting pressure Shape of collapsingblock Upper bound theorem