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Supersymmetry for Fermion Masses

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Communications in Theoretical Physics 2007年第6期47卷 1088-1098页

作者： liu chun Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China

It is proposed that supersymmetry （SUSY） may be used to understand fermion mass hierarchies. A family symmetry ZSL is introduced, which is the cyclic symmetry among the three generation SU（2） doublets. SUSY breaks at a high energy scale - 10^11 GeV. The electroweak energy scale- 100 GeV is unnaturally small No additional global symmetry, like the R-parlty, is imposed. The Yukawa couplings and R-parity violating couplings all take their natural values, which are О（10^0 -10^-2）. Under the family symmetry, only the third generation charged ferrnions get their masses. This family symmetry is broken in the soft SUSY breaking terms, which result in a hierarchical pattern of the fermion masses. It turns out that for the charged leptons, the r mass is from the Higgs vacuum expectation value （VEV） and the sneutrino VEVs, the muon mass is due to the sneutrino VEVs, and the electron gains its mass due to both ZZL and SUSY hreaking. The large neutrino mixing are produced with neutralinos playing the partial role of right-handed neutrinos. │Ve3│, which is for Ve-Vr mixing, is expected to be about 0.1. For the quarks, the third generation masses are from the Higgs VEVs, the second generation masses are from quantum corrections, and the down quark mass due to the sneutrino VEVs. It explains me/ms, ms/me, md 〉 mu and so on. Other aspects of the model are discussed.

关键词： fermion mass family symmetry supersymmetry

Multiobjective evolutionary algorithm for dynamic nonlinear constrained optimization problems

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Journal of Systems Engineering and Electronics 2009年第1期20卷 204-210页

作者： liu chun'an Wang Yuping Dept. of Mathematics Baoji Univ. of Arts and Science Baoji 721013 P. R. China School of Computer Engineering and Technology Xidian Univ. Xi'an 710071 P. R. China

A new method to solve dynamic nonlinear constrained optimization problems （DNCOP） is proposed. First, the time （environment） variable period of DNCOP is divided into several equal subperiods. In each subperiod, the DNCOP is approximated by a static nonlinear constrained optimization problem （SNCOP）. Second, for each SNCOP, inspired by the idea of multiobjective optimization, it is transformed into a static bi-objective optimization problem. As a result, the original DNCOP is approximately transformed into several static bi-objective optimization problems. Third, a new multiobjective evolutionary algorithm is proposed based on a new selection operator and an improved nonuniformity mutation operator. The simulation results indicate that the proposed algorithm is effective for DNCOP.

关键词： dynamic optimization nonlinear constrained optimization evolutionary algorithm optimal solutions

(G'/G)-Expansion Method Equivalent to Extended Tanh Function Method

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Communications in Theoretical Physics 2009年第6期51卷 985-988页

作者： liu chun-Ping Institute of Mathematics Yangzhou University Yangzhou 225002 China

In a recent article [Physics Letters A 372 （2008） 417], Wang et al. proposed a method, which is called the （G′/G）-expansion method, to look for travelling wave solutions of nonlinear evolution equations. The travelling wave solutions involving parameters of the KdV equation, the mKdV equation, the variant Boussinesq equations, and the Hirota-Satsuma equations are obtained by using this method. They think the （G′/G）-expansion method is a new method and more travelling wave solutions of many nonlinear evolution equations can be obtained. In this paper, we will show that the （G′/G）-expansion method is equivalent to the extended tanh function method.

关键词： (G′/G)-expansion method extended tanh function method Riccati equation KdV equation

Numerical Study on the Linear and Nonlinear Behavior of A Fluid-Filled Piezoelectric Membrane Under Gravity Waves

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China Ocean Engineering 2023年第5期37卷 768-780页

作者： liu chun-rong YANG Wen-yu School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China

This study integrated piezoelectric layers in a flexible membrane to form a piezoelectric membrane.A fluid-filled piezoelectric membrane,which can be used as breakwater and wave energy converter simultaneously,was *** mathematical models to describe the interactions of the waves with the piezoelectric membrane were *** dimensionless parameters to control the behavior of the piezoelectric membrane were *** mixed EulerianLagrangian method was employed to simulate the mathematical *** simulation code was *** on the simulation results,the effects of dimensionless elastic modulus of the membrane E^(*),tension of the membrane T_(0)^(*)and the resistance of the load R^(*)on the behavior of the piezoelectric membrane were *** E^(*)is small(E^(*)0.0001),the response of the piezoelectric membrane can be considered as *** linear response,the minimum transmission coefficient and maximum output electric power of the piezoelectric membrane can be achieved simultaneously by adjusting T_(0)^(*)and R^(*).For larger E^(*),nonlinear behavior of the piezoelectric membrane is *** some larger values of E^(*),working frequency of piezoelectric elements can reach eight times the wave *** these cases,higher output electric power can be achieved for smaller strain of the membrane.

关键词： wave energy breakwater piezoelectric membrane nonlinear

Advances in urban information extraction from high-resolution remote sensing imagery

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Science China Earth Sciences 2020年第4期63卷 463-475页

作者： Jianya GONG chun liu Xin HUANG School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

The study of urban area is one of the hottest research topics in the field of remote sensing. With the accumulation of high-resolution(HR) remote sensing data and emerging of new satellite sensors, HR observation of urban areas has become increasingly possible, which provides us with more elaborate urban information. However, the strong heterogeneity in the spectral and spatial domain of HR imagery brings great challenges to urban remote sensing. In recent years, numerous approaches were proposed to deal with HR image interpretation over complex urban scenes, including a series of features from low level to high level, as well as state-of-the-art methods depicting not only the urban extent, but also the intra-urban variations. In this paper, we aim to summarize the major advances in HR urban remote sensing from the aspects of feature representation and information extraction. Moreover, the future trends are discussed from the perspectives of methodology, urban structure and pattern characterization, big data challenge, and global mapping.

关键词： High-resolution Urban remote sensing Feature extraction Land use/land cover classification Change detection

TDDFT-SOS Studies on the Polarizabilities and Second-order Hyperpolarizabilities of Zn_3O_3 II-VI Semiconductor Clusters

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1359-1364页

作者： QIU Yong-Qing liu Yi-chun Advanced Center for Opto-electronic Functional MaterialResearch Northeast Normal University Changchun 130024 China Key Laboratory of Excited State Physics Change＇hun Institute of OpticsFine Mechanics and Physics The Chinese Academy of Sciences Changchun 130021 China

The geometrical structure of semiconductor clusters including Zn3O3 was optimized by the DFT B3LYP method. With the same basis sets, dipole moments, polarizabilities and secondorder hyperpolarizabilities have been calculated and compared with the results obtained by TDDFT B3LYP method combined with sum-over-state （SOS） formula. The calculation results indicate that the dipole moments of the ground state depend on the atom radius and electronegative differences between elements and are their balance point as well. The polarizabilities of the clusters accord with the rule of the corresponding energy transformation from ground to excited state. The results predict an increase of second-order hyperpolarizabilities with increasing the distances between atoms in the clusters as well as a decrease of the polarizabilities and second-order hyperpolarizabilities in the same serial of semiconductor clusters with increasing the dipole moments of the ground states. The changes of dipole moments in ground states are inconsistent with transition moments. Spatial structure, charge transfer and other factors play an important role in composing the transition moments.

关键词： Ⅱ-Ⅵ semiconductor clusters TDDFT method polarizabilities second-order hyperpolarizabilities

Impact of community public health care on treatment effect,health cognition,and self-management in patients with type 2 diabetes

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World Journal of Clinical Cases 2025年第5期13卷 22-29页

作者： Hong Shi chun liu Hong-Yan Luo Department of Infrastructure Operation West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Public Health Minzu Street Community Health Service CenterWuhan 430000Hubei ProvinceChina Caotang Community Health Service Center Chengdu 610031Sichuan ProvinceChina

BACKGROUND At present,China has become the country with the largest number of individuals with diabetes mellitus(DM)in the world,with a total of approximately 140 million patients,the majority of whom have type 2 DM(T2DM).Based on conven-tional nursing methods,community home care has important clinical significance in controlling blood sugar and disease *** To explore the impact of community public health nursing on treatment effect,health cognition,and self-management in patients with *** One hundred patients with T2DM were selected as the research *** patients were divided into either a conventional nursing group or community nursing(CN)group using the random number table *** conventional nursing group(50 cases)received routine care,while the CN group(50 cases)received community public health care in addition to routine care as that for the conventional nursing *** rate of excellent and good blood glucose control,fasting blood glucose before and after care,2-h postprandial blood glucose,health cognition,and self-management ability,and patient satisfaction were compared between the two *** The CN group had a higher rate of excellent blood sugar control than the conventional nursing group(88%vs 70%,P0.05).After nursing,fasting blood glucose and 2-h postprandial blood glucose were reduced to varying degrees in both groups,and both blood glucose levels in the CN group were lower than those of the conventional nursing group(P<0.05).Compared with the scores before care,the cognitive level score for diabetes and self-management ability score improved after care in both *** cognitive level and self-management ability of patients in the CN group were higher than those of the conventional nursing group(P<0.05).The overall satisfaction of the CN group was better than

关键词： Community public health care Type 2 diabetes Blood sugar control Self-management ability Cognition level

Relationship Among Solutions of a Generalized Riccati Equation

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Communications in Theoretical Physics 2007年第4X期48卷 610-614页

作者： liu Xiao-Ping liu chun-Ping Institute of Mathematics Yangzhou University Yangzhou 225002 China Gaoyou Branch Yangzhou Education College Gaoyou 225600 China

In this paper, some solutions of a generalized Riccati equation are investigated, which are given in the recent articles [Chaos, Solitons ＆ Fractals 24 （2005） 257; Phys. Lett. A 336 （2005） 463], and the relations... 详细信息

关键词： generalized Riccati equation nonlinear partial differential equations exact solution

Microstructure Evolution and Strain-Dependent Constitutive Modeling to Predict the Flow Behavior of 20Cr–24Ni–6Mo Super-Austenitic Stainless Steel During Hot Deformation

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Acta Metallurgica Sinica(English Letters) 2018年第4期31卷 401-414页

作者： Yan-Sen Hao Wan-chun liu Zhen-Yu liu State Key Laboratory of Rolling and Automation Northeastern University

Hot compression tests were carried out with specimens of 20Cr-24Ni-6Mo super-austenitic stainless steel at strain rate from 0.01 to 10 s^-1 in the temperature range from 950 to 1150 ℃,and flow behavior was *** analysis indicated that dynamic recrystallization（DRX）behavior was more sensitive to the temperature than strain rate,and full DRX was obtained when the specimen deformed at 1150℃.When the temperature reduced to 1050 ℃,full DRX was completed at the highest strain rate 10 s-l rather than at the lowest strain rate 0.01 s-1 because the adiabatic heating was pronounced at higher strain *** addition,flow behavior reflected in flow curves was inconsistent with the actual microstructural evolution during hot deformation,especially at higher strain rates and lower ***,flow curves were revised in consideration of the effects of adiabatic heating and friction during hot *** results showed that adiabatic heating became greater with the increase of strain level,strain rate and the decrease of temperature,while the frictional effect cannot be neglected at high strain ***,based on the revised flow curves,strain-dependent constitutive modeling was developed and verified by comparing the predicted data with the experimental data and the modified *** result suggested that the developed constitutive modeling can more adequately predict the flow behavior reflected by corrected flow curves than that reflected by experimental flow curves,even though some difference existed at 950℃ and 0.01 s^-*** main reason was that plenty of precipitates generated at this deformation condition and affected the DRX behavior and deformation behavior,eventually resulted in dramatic increase of deformation resistance.

关键词： Super-austenitic stainless steel Hot compression Adiabatic heating Constitutive modeling Microstructure evolution