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A New Type of Mei Adiabatic Invariant Induced by Perturbation to Mei Symmetry of Hamiltonian Systems

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Communications in Theoretical Physics 2009年第7期52卷 12-16页

作者： ding Ning fang Jian-Hui Department of Physics and Electronics Science Binzhou University Binzhou 256600 China College of Physics Science and Technology China University of Petroleum Dongying 257061 China

Considering full perturbation to infinitesimal generators in the Mei structure equation,a new type of Meiadiabatic invariant induced by perturbation to Mei symmetry for Hamiltonian system was reported.

关键词： Mei symmetry perturbation Mei adiabatic invariant Hamiltonian system

Perturbation to Mei Symmetry and Noether Adiabatic Invariants for Birkhoffian Systems

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Communications in Theoretical Physics 2008年第6期49卷 1410-1412页

Based on the concept of adiabatic invariant, the perturbation to Mei symmetry and Noether adiabatic invariants for Birkhoffian systems are studied. The exact invariants of Mei symmetry for the system without perturbation are given. The perturbation to Mei symmetry is discussed and the Noether adiabatic invariants induced from the perturbation to Mei symmetry of the system are obtained.

关键词： Mei symmetry perturbation Noether adiabatic invariant Birkhoffian system

Regaining China's Resource Reallocative Efficiency to Boost Growth

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China & World Economy 2023年第1期31卷 5-21页

作者： fang cai Chinese Academy of Social Sciences China

The structural changes that the Chinese economy has been experiencing since its working-age population began to decline pose challenges for its further ***,as it loses its comparative advantage in labor-intensive activities,the share of manufacturing in its GDP has ***,unproductive enterprises that are reluctant to exit the market tend to seek policy protection,which leads to the immobility of resource ***,the reallocation of the labor force from the highly productive manufacturing sector to the low-productivity service sector leads to the degradation of resource *** inadequate exploitation of the potential of resource reallocation implies that the decline in manufacturing is *** is therefore important to combine market competition policy,industrial policy,and social protection policy to stabilize the development of manufacturing.

关键词： labor productivity resource reallocation share of manufacturing total factor productivity

Lie Symmetry and Conserved Quantities for Nonholonomic Vacco Dynamical Systems

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Communications in Theoretical Physics 2006年第2X期46卷 265-268页

作者： ding Ning fang Jian-Hui College of Physics and Technology China University of Petroleum Dongying 257061 China

In this paper the Lie symmetry and conserved quantities for nonholonomic Vacco dynamical systems are studied. The determining equation of the Lie symmetry for the system is given. The general Hojman conserved quantity... 详细信息

关键词： Vacco dynamical system Lie symmetry general Hojman conserved quantity Lutzky conserved quantity

The Second Demographic Dividend as a Driver of China's Growth

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China & World Economy 2020年第5期28卷 26-44页

作者： fang cai Chinese Academy of Social Sciences China

As China’s demographic transition enters a new stage,the“first demographic dividend”-the economic advantage resulting from demographic changes in recent decades-is bound to disappear *** s future development will be characterized by an aging ***“second demographic dividend”refers to new sources of economic growth derived from this later population *** paper reveals major constraints caused by aging in China,which is characterized by a tendency to grow old before becoming *** the population ages,human capital improvement slows,labor force participation declines and consumption power *** paper suggests taking advantage of a population“echo effect”to improve human capital at all ages,to enhance workers’ability to benefit from employment,and to improve the labor participation rate of the elderly,which in turn would increase the income and social security of the *** measures are conducive tofuture economic growth and to the cultivation of the second demographic dividend.

关键词： aging demographic dividend labor force participation population echo effect

Improved Upper Bound for Generalized Acyclic Chromatic Number of Graphs

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 798-800页

作者： Jian-sheng cai Xu-ding ZHU School of Mathematics and Information Sciences Weifang University Weifang 261061 China Department of Mathematics Zhejiang Normal University Jinhua 321004 China

A vertex coloring of a graph G is called r-acyclic if it is a proper vertex coloring such that every cycle D receives at least min{｜D｜, r} colors. The r-acyclic chromatic number of G is the least number of colors in an r-acyclic coloring of G. We prove that for any number r ≥ 4, the r-acyclic chromatic number of any graph G with maximum degree △ ≥ 7 and with girth at least（r-1）△ is at most（4r-3）△.

关键词： girth coloring acyclic coloring τ-acyclic coloring Lopsided local lemma

Axisymmetric Stokes Exterior Problem and Its Numerical Computation

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 115-128页

作者： Neng-sheng fang cai-xiu Liao School of Finance Southwestern University of Finance and Economics Chengdu Sichuan 611130 China School of Mathematical Sciences Xiamen University Fujian 361005 China School of Mathematical Sciences South China Normal University Guangzhou 510631 China

We establish variational formulation and prove the existence and uniqueness of the three dimen- sional axisymmetric Stokes exterior problem in weighted spaces. Error estimates and convergence for P2 - P0 elements with infinite element methods are also obtained. Numerical experiments are presented to verify the theoretical analysis.

关键词： Axisyrnmetric flow Stokes equation exterior problem infinite element method

Hyperbolic Metric and Normal Family

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Acta Mathematica Sinica,English Series 2014年第4期30卷 681-688页

作者： cai Yun fang Xue Cheng PANG School of Mathematical Sciences Fudan University School of Mathematical Sciences Nanjing Normal University Department of Mathematics East China Normal University

In this paper, we study the normality of the family of meromorphic functions from the viewpoint of hyperbolic metric. Then, a new sufficient and necessary condition is obtained, which can determine a given family of m... 详细信息

关键词： Hyperbolic metric normal family holomorphic function meromorphic function

Effects of cilostazol on the progression and regression of symptomatic intracranial artery stenosis:it reduces the risk of ischemic stroke

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Neural Regeneration Research 2015年第4期10卷 667-672页

作者： Wen-hui Zhang fang-fang cai Zhong-min Wen Department of Neurology Second Affiliated Hospital of Soochow University

OBJeCTIve：To assess the efifcacy and safety of cilostazol on the progression and regression of symptomatic intracranial artery stenosis. DATA ReTRIvAL： We searched the main databases for eligible trials including Medline （from 1966 to June 2014）, Embase （from 1980 to June 2014）, Cochrane Library （Issue 6, 2014）, Chinese National Knowledge Infrastructure （from 1995 to June 2014）, Current Controlled Trials （http：//***）, Clinical *** （http：//***）, and Chinese Clinical Trial Registry （http：//***）. All studies regarding prevention and treatment of symptomatic intracranial arterial stenosis by cilostazol were collected. The Mesh or text keywords were the En-glish words： “cilostazol, phosphodiesterase 3 inhibitor, atherosclerosis, and ischemic stroke.” No restrictions were put on publications or publication language. SeLeCTION CRITeRIA：Grade A or B randomized controlled trials were selected according to the quality of evaluation criteria from the Cochrane Collaboration, in which cilostazol and aspi-rin were used to evaluate the effects of cilostazol in the treatment of patients with symptomatic intracranial artery stenosis. The quality of study methodology was evaluated based on criteria de-scribed in Cochrane Reviewer’s Handbook 5.0.1. RevMan 5.2 software was used for data analysis. MAIN OUTCOMe MeASUReS： Clinical efifcacy and safety of cilostazol in stopping progression and promoting regression of symptomatic intracranial artery stenosis were measured by magnet-ic resonance angiography and transcranial Doppler. ReSULTS：Two randomized controlled trials with a total of 203 patients were included in this study. The results showed that while cilostazol was associated with a significantly reduced progression of intracranial artery stenosis （OR = 0.21, 95%CI： 0.09–0.47,P 〈 0.01）, it had no beneifcial effect on symptom regression （OR = 1.42, 95%CI： 0.80–2.51,P = 0.24）. During the follow-up period, although some adverse effects

关键词： nerve regeneration systemic review cilostazol atherosclerosis aspirin stroke,ischemic magnetic resonance angiography transcranial Doppler intracranial artery stenosis follow-up studies neural regeneration