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Dynamic characteristics of multi-span spinning beams with elastic constraints under an axial compressive force

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 295-310页

作者： Xiaodong GUO zhu su Lifeng WANG State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is *** displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the *** exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange *** efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other *** effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are *** results show that the present method can freely simulate any boundary constraints without modifying the solution *** elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of *** an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.

关键词： multi-span spinning beam elastic constraint improved Fourier series free vibration semi-analytical solution

Flutter analysis of rotating beams with elastic restraints

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Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 761-776页

作者： Lüsen WANG zhu su Lifeng WANG State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The aeroelastic stability of rotating beams with elastic restraints is *** coupled bending-torsional Euler-Bernoulli beam and Timoshenko beam models are adopted for the structural *** Greenberg aerodynamic model is used to describe the unsteady aerodynamic *** additional centrifugal stiffness effect and elastic boundary conditions are considered in the form of potential energy.A modified Fourier series method is used to assume the displacement field function and solve the governing *** convergence and accuracy of the method are verified by comparison of numerical ***,the flutter analysis of the rotating beam structure is carried out,and the critical rotational velocity of the flutter is *** results show that the elastic boundary reduces the critical flutter velocity of the rotating beam,and the elastic range of torsional spring is larger than the elastic range of linear spring.

关键词： rotating beam modified Fourier series method elastic restraint flutter

Overcoming doping bottleneck by using surfactant and strain

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Frontiers of Materials Science 2011年第4期5卷 335-341页

作者： Junyi zhu su-Huai WEI National Renewable Energy Laboratory Golden Colorado 80401 USA

Overcoming the doping bottleneck in semiconductors, especially in wide band gap semiconductors, has been a challenge in semiconductor physics for many years. In this paper, we review some recent progresses in enhancing doping by surfactant and strain. We show that surfactant and strain are two effective approaches to enhance dopant solubility in epitaxial growth. The surfactant can introduce an energy level deep inside the band gap, making the host compound less stable, thus lower the formation energy of the intentional dopant. The strain enhanced doping is based on the observation that dopant induces volume change in the host. If the external strain is in the same direction as the dopant induced volume change, the formation energy of the dopant is reduced. This effect can be used to tune doping sites, thus doping type, in a host. A hybrid method to both include strain and surfactant is proposed, which can be a promising general method to further enhance doping.

关键词： semiconductor surfactant strain doping band gap

Transverse shear and normal deformation effects on vibration behaviors of functionally graded micro-beams

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Applied Mathematics and Mechanics(English Edition) 2020年第9期41卷 1303-1320页

作者： zhu su Lifeng WANG Kaipeng suN Jie suN State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shanghai Institute of Satellite Engineering Shanghai 201109China

A quasi-three dimensional model is proposed for the vibration analysis of functionally graded(FG)micro-beams with general boundary conditions based on the modified strain gradient *** consider the effects of transverse shear and nor-mal deformations,a general displacement field is achieved by relaxing the assumption of the constant transverse displacement through the *** conventional beam theories including the classical beam theory,the first-order beam theory,and the higher-order beam theory are regarded as the special cases of this *** material proper-ties changing gradually along the thickness direction are calculated by the Mori-Tanaka *** energy-based formulation is derived by a variational method integrated with the penalty function method,where the Chebyshev orthogonal polynomials are used as the basis function of the displacement *** formulation is validated by some comparative examples,and then the parametric studies are conducted to investigate the effects of transverse shear and normal deformations on vibration behaviors.

关键词： quasi-three dimensional theory modified strain gradient theory function-ally graded(FG)micro-beam size effect vibration general boundary condition

surface evolution caused by curvature driven forces based on natural exponential pair potential

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Acta Mechanica Sinica 2019年第2期35卷 445-456页

作者： Dan Wang Yajun Yin Zheng Zhong zhu su Zhili Hu State key laboratory of mechanics and control of mechanical structures College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 211100 China Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing 100084 China School of Aerospace Engineering and Applied Mechanics Tongji University Shanghai 200092 China

Based on the natural exponential pair potential, the interaction potential between curved surface body and on surface particle is studied. Firstly, the interaction potential is written as a function of curvatures through the differential geometry. Secondly, idealized numerical experiments are designed to test the accuracy of curvature-based potential. Then, the driving forces induced by curvatures are analyzed, which confirms that micro/nano curved surface body can induce driving forces, curvatures and the gradient of curvatures are the essential elements forming the driving forces. Finally, by combing with the curvature based potential and driving forces, the movements of on surface particles and the evolution of surface morphology of curved surface body are predicted.

关键词： Curvature-based potential Curvatures and the gradient of curvatures Driving forces surface morphology evolution

Evolvable dialogue state tracking for statistical dialogue management

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Frontiers of Computer Science 2016年第2期10卷 201-215页

作者： Kai YU Lu CHEN Kai suN Qizhe XIE su zhu Key Laboratory of Shanghai Education Commission for Intelligent Interaction and Cognitive EngineeringSpeechLab Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Computer Science Cornell University Ithaca NY 14853 USA

Statistical dialogue management is the core of cognitive spoken dialogue systems （SDS） and has attracted great research interest. In recent years, SDS with the ability of evolution is of particular interest and becomes the cuttingedge of SDS research. Dialogue state tracking （DST） is a process to estimate the distribution of the dialogue states at each dialogue turn, given the previous interaction history. It plays an important role in statistical dialogue management. To provide a common testbed for advancing the research of DST, international DST challenges （DSTC） have been organised and well-attended by major SDS groups in the world. This paper reviews recent progresses on rule-based and statistical approaches during the challenges. In particular, this paper is focused on evolvable DST approaches for dialogue domain extension. The two primary aspects for evolution, semantic parsing and tracker, are discussed. Semantic enhancement and a DST framework which bridges rule-based and statistical models are introduced in detail. By effectively incorporating prior knowledge of dialogue state transition and the ability of being data-driven, the new framework supports reliable domain extension with little data and can continuously improve with more data available. This makes it excellent candidate for DST evolution. Experiments show that the evolvable DST approaches can achieve the state-of-the-art performance and outperform all previously submitted trackers in the third DSTC.

关键词： dialogue management domain extension,evolvable dialogue state tracking parser tracker

Responsive Polymeric Nanoparticles for Biofilm-infection Control

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Chinese Journal of Polymer Science 2021年第11期39卷 1376-1391页

作者： Lin-zhu su Yong Liu Yuan-Feng Li Ying-Li An Lin-Qi Shi State Key Laboratory of Medicinal Chemical Biology Key Laboratory of Functional Polymer MaterialsMinistry of EducationInstitute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China Engineering Research Center of Clinical Functional Materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesOujiang LaboratoryWenzhou 325000China

With the emergence of multidrug resistance(MDR)in many pathogens,bacterial infections are becoming a growing threat to public *** frightening scenario is due largely to the formation of biofilms,in which the bacteria are extremely recalcitrant to the conventional antibiotic *** address the emergence of MDR and biofilm-associated infections,numerous polymer-based materials have been designed and prepared *** subject of this perspective is the recent development of polymer-based materials that have been applied to combat multidrug-resistant pathogens,to prevent the formation of biofilms,or enhance the eradication efficacy to mature biofilms via killing biofilm-bacteria or dispersing *** advantages and shortcomings of these polymer-based materials are discussed,as well as the challenges we are facing in the clinical translation of these systems.

关键词： Antibacterial Biofilm Multidrug resistance Polymeric nanoparticles Stimuli-responsive

Intestinal glucagon-like peptide-1:A new regulator of impaired counterregulatory responses to hypoglycemia in type 1 diabetes mellitus

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World Journal of Diabetes 2025年第1期16卷 217-221页

作者： Le-Rong Liu Yuan-Yuan Luo Pei-zhu su Cong Zhang Zhao-Tao Li Department of Endocrinology and Metabolism Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Endocrinology Chongqing University Three Gorges HospitalChongqing 404100China Chongqing Municipality Clinical Research Center for Endocrinology and Metabolic Diseases Chongqing University Three Gorges HospitalChongqing 404100China Department of Endocrinology The Second Affiliated HospitalChongqing Medical UniversityChongqing 400013China Department of Gastroenterology The First People's Hospital of FoshanFoshan 528000Guangdong ProvinceChina

In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With the global rise of T1DM,there is an increased burden on society and healthcare *** to insulin therapy and islet dysfunction,T1DM patients are highly vulnerable to severe hypoglycemia,a leading cause of *** healthy individuals,counterregulatory mechanisms restore blood glucose during hypoglycemia,but repeated episodes impair these *** et al demonstrated that overexpression of GLP-1 attenuates the sympathetic-adrenal reflex and disrupts the secretion of counterregulatory hormones such as glucagon during hypoglycemia,leading to counterregulatory *** findings highlight the critical role of GLP-1 in the impaired counterregulatory response to hypoglycemia in T1DM patients and provide new insights into the potential application of GLP-1-related therapies in T1DM patients.

关键词： Glucagon-like peptide-1 Impaired counterregulation Type 1 diabetes mellitus Sympathetic-adrenal reflex Glucagon

Myricetin alleviates ovalbumin-induced allergic rhinitis in mice by regulating Th1/Th2 balance

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Asian Pacific Journal of Tropical Biomedicine 2023年第7期13卷 306-314页

作者： Ya-Nan Shi Jin-zhu su Juan Wang Jiang-Qiao Geng Department of Otolaryngology Sanya Women and Children's HospitalSanya572000China Department of Otolaryngology Hebei Children’s HospitalShijiazhuang050031China

Objective:To evaluate the effect of myricetin on ovalbumin(OVA)-induced allergic rhinitis in ***:Mice were sensitized and challenged using OVA(5%,500 mL)intraperitoneally and intranasally,respectively,on an alternative day for 14 days,followed by administration of myricetin(50,100,and 200 mg/kg)till day *** symptoms,biochemical parameters,protein expressions,and histopathology were ***:OVA-induced increased nasal symptoms including rubbing,sneezing,and discharge were significantly reduced by myricetin(100and 200 mg/kg)(P<0.05).Myricetin also protected against histamine challenge and attenuated elevated serum immunoglobulin E(IgE;total and OVA-specific),total IgG1,andβ-hexosaminidase levels,as well as leukotriene C4 and interleukins levels in nasal lavage fluid(P<0.05).Western blot analysis showed that myricetin significantly upregulated the protein expression of T-box expressed in T cells,while downregulating the protein expression of GATA binding protein 3,NF-κB,and IκB-α(P<0.05).Additionally,OVA-induced histopathological abberations in the nasal mucosa was markedly ameliorated by myricetin treatment(P<0.05).Conclusions:Myricetin exerts anti-allergic effects against OVAinduced allergic rhinitis via regulating Th1/Th2 balance.

关键词： Allergic rhinitis GATA3 Interleukins Myricetin Montelukast Ovalbumin Th1/Th2 balance