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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

The war between wheat and Fusarum: fighting with an alien weapon

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Science China(Life Sciences) 2020年第9期63卷 1425-1427页

作者： chun-Ming liu Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China

Wheat, as one of the most important staple food crops in the world, has been domesticated and cultivated for over5,000 years. The flour of common wheat (Triticum aestivum L.) is used daily to make different types of foods in different regions, typically bread, pizza and pasta for western countries, and noodle, dumpling and steamed bread for Asian countries. Infections of Fusarium species cause impactful diseases for cereal crops including wheat, rice, maize and barley. Outbreaks of devastating infections by Fusarium species may lead to up to 50%yield loss in these crops and the contaminations of trichothecene mycotoxins. Therefore,it is an important issue for both food security and food safety.

关键词： crops Wheat cultivated

New year,new look,and new goals

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Journal of Integrative Plant Biology 2014年第1期56卷 2-3页

作者： chun-Ming liu JIPB Institute of Botany the Chinese Academy of Sciences Beijing China

Each year, January offers me the opportunity to reflect on what has happened in the past years and to anticipate what is going to happen in coming years. The last few years have without a doubt been an exciting period for JIPB, it has continued to progress, and become a prestigious international journal （liu 2012）. In 5 years, JIPB＇s subscriptions have grown from 7,853 to over 14,300 libraries worldwide, and the impact factor has increased from 0.859 to 3.75. The number of full- text downloads has increased from 68,851 to 200,000 （liu 2013）. As we step into 2014, you will notice some important changes, and of course some challenges we will have to face.

关键词： UK New year,new look,and new goals

JIPB Board,supporting the plant science community through teamwork

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Journal of Integrative Plant Biology 2015年第4期57卷 326-327页

作者： chun-Ming liu The Chinese Academy of Sciences

The purpose of scientific journals is to serve as a public depository for research endeavors, allowing people to share research results and opinions with their peers. In the fast-developing modern world, various tools are available to evaluate the track record, or publication profile of a scientist. Pursuits to achieve research results that are published in the highest impact factor （IF） journals has often become the aim of the ＂game＂, Consequently, manipulating publications to obtain higher impact factors has also become the aim of game in some journals. However, at JIPB, we do things differently.

关键词： Mo USA JIPB Board,supporting the plant science community through teamwork

(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

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Sepsis heterogeneity

World Journal of Pediatrics 2023年第10期19卷 919-927页

作者： Wei Wang chun-Feng liu Department of Pediatrics ShengJing Hospital of China Medical UniversityNo.36SanHao StreetShenyang CityLiaoning Province 110004China

Background Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection,with extremely high ***,sepsis is a heterogeneous syndrome characterized by a vast,multidimensional array of clinical and biologic features,which has hindered advances in the therapeutic field beyond the current *** sources We used PubMed to search the subject-related medical literature by searching for the following single and/or combination keywords:sepsis,heterogeneity,personalized treatment,host response,infection,epidemiology,mortality,incidence,age,children,sex,comorbidities,gene susceptibility,infection sites,bacteria,fungi,virus,host response,organ dysfunction and *** We found that host factors(age,biological sex,comorbidities,and genetics),infection etiology,host response dysregulation and multiple organ dysfunctions can all result in different disease manifestations,progression,and response to treatment,which make it difficult to effectively treat and manage sepsis *** Herein,we have summarized contributing factors to sepsis heterogeneity,including host factors,infection etiology,host response dysregulation,and multiple organ dysfunctions,from the key elements of pathogenesis of *** in-depth understanding of the factors that contribute to the heterogeneity of sepsis will help clinicians understand the complexity of sepsis and enable researchers to conduct more personalized clinical studies for homogenous patients.

关键词： Heterogeneity Host response Infection Personalized treatment Sepsis