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Weighted approximation of functions with singularities by Bernstein operators

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2008年第10期9卷 1451-1456页

作者： Bao-rong WEI Yi ZHAO Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Institute of Mathematics Hangzhou Dianzi University Hangzhou 310018 China

As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimates for weighted approximation of functions with singularities by Bernstein operators. The main results are the Jackson＇s estimates of functions f∈ （Wwλ）2 andre Cw, which extends the result of （Della Vecchia et al., 2004）.

关键词： Bemstein operators Functions with singularities Weighted approximation Pointwise estimates

Virtual 3D environment for exploring the spatial ability of students

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Virtual Reality & Intelligent Hardware 2020年第6期2卷 556-568页

作者： Yingqian LI Yang YANG Zhengwei YAO Guangtao XU Department of Educational Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Application Technology Hangzhou Normal UniversityHangzhou 311121China hangzhou normal university China

Background Spatial ability is an unique type of intelligence;it can be distinguished from other forms of intelligence and plays an essential role in an individual's success in many academic fields,particular in this era of ***-assisted 3D technology can display stereo graphics and promote students'understanding of the geometrical structure and characteristics of *** ability includes several *** software programs are available for training different aspects of spatial ability for senior high school *** study aims to explore an effective method for training the spatial ability for senior high school students,and to promote the development of students'independent inquiry *** First,an inquiry design strategy to improve the spatial ability of students is *** on this strategy,unity3D was used to develop a 3D inquiry environment that can use leap motion to complete a gesture ***,researchers carried out experience-based activities and issued user experience questionnaires to participants to verify the application effect of the spatial ability inquiry environment and used interviews to understand the user experience of participants exploring the leap motion device in a 3D inquiry *** 32 learners participated in the *** have a high score for perceived usefulness and willingness to *** with the perceived ease of use and perceived usefulness,the average score of the application effect is relatively *** terms of willingness to use,most of the learners expressed their willingness to use a similar inquiry environment for spatial ability training in the *** The spatial ability inquiry environment can help learners better understand different *** users showed a strong willingness to continue using the *** device also updates the teaching concept to a certain extent and emphasizes the dominant position of a student.

关键词： 3D Inquiry learning Spatial ability 3D inquiry environment Leap motion

Condensation Behavior of Ag Aggregates on Liquid Surfaces

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Chinese Physics Letters 2010年第1期27卷 151-154页

作者：张晓飞张初航吕能谢建平叶高翔 Department of Physics Zhejiang University Hangzhou 310027 Department of Physics Hangzhou Normal University Hangzhou 310036

We report a condensation behavior of silver aggregates on silicone oil surfaces. The deposited Ag atoms diffuse and aggregate on the oil surface, and then form granular clusters and ramified islands. The apparent Ag coverage of the total area increases linearly with the nominal film thickness h for h 〈 0.9nm. However, the coverage exhibits a fluctuation behavior for 1.0 nm 〈 h〈 2.5 nm. It is found that the anomalous behavior of the coverage is resulted from a characteristic material condensation process in the aggregates.

关键词： CONDENSATION SILICONES THIN films THICKNESS measurement SILVER FLUCTUATIONS (Physics)

Bootstrap Inference on the Variance Component Functions in the Two-Way Random Effects Model with Interaction

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Journal of Systems Science & Complexity 2021年第2期34卷 774-791页

作者： YE Rendao GE Wenting LUO Kun School of Economics Hangzhou Dianzi UniversityHangzhou 310018China Alibaba Business College Hangzhou Normal UniversityHangzhou 310036China

In this paper,using the Bootstrap approach and generalized approach,the authors consider the one-sided hypothesis testing problems for variance component functions in the two-way random effects ***,the test statistics and confidence intervals for the sum of variance components are ***,the one-sided hypothesis testing problems for the ratio of variance components are also *** Monte Carlo simulation results indicate that the Bootstrap approach is better than the generalized approach in most ***,the above approaches are applied to the real data examples of mice blood p H and molded plastic part’s dimensions.

关键词： Bootstrap generalized approach two-way random effects model variance component function

Stability and Turing Patterns of a Predator-prey Model with Holling Type Ⅱ Functional Response and Allee Effect in Predator

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 675-695页

作者： Lu CHEN Feng YANG Yong-li SONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121China

In this paper, we are concerned with a predator-prey model with Holling type Ⅱ functional response and Allee effect in predator. We first mathematically explore how the Allee effect affects the existence and stability of the positive equilibrium for the system without diffusion. The explicit dependent condition of the existence of the positive equilibrium on the strength of Allee effect is determined. It has been shown that there exist two positive equilibria for some modulate strength of Allee effect. The influence of the strength of the Allee effect on the stability of the coexistence equilibrium corresponding to high predator biomass is completely investigated and the analytically critical values of Hopf bifurcations are theoretically *** have shown that there exists stability switches induced by Allee effect. Finally, the diffusion-driven Turing instability, which can not occur for the original system without Allee effect in predator, is explored, and it has been shown that there exists diffusion-driven Turing instability for the case when predator spread slower than prey because of the existence of Allee effect in predator.

关键词： predator-prey model Allee effect diffusion stability Turing bifurcation

Bubble nucleation in the two-flavor quark-meson model

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Chinese Physics C 2024年第5期48卷 92-106页

作者：汪俊荣余紫琬毛鸿 School of Physics Hangzhou Normal UniversityHangzhou 311121China

We investigate the dynamics of a first-order quark-hadron transition via homogeneous thermal nucleation in the two-flavor quark-meson *** contribution of the fermionic vacuum loop in the effective thermodynamics potential and phase diagram,together with the location of the critical endpoint(CEP),is obtained in the temperature and chemical potential *** weak and strong first-order phase transitions,by taking the temperature as a variable,the critical bubble profiles,evolutions of the surface tension,and saddle-point action in the presence of a nucleation bubble are numerically calculated in detail when fixing the chemical potentials atμ=306 MeV andμ=309 *** results show that the system could be trapped in the metastable state for a long time as long as the temperature is between the metastable region characterized by the up and low spinodal ***,the surface tension at criticality will rise to approximately 4 MeV/fm2 when the chemical potential is very *** a small surface tension value would favor a mixed phase in the cores of compact stars and may have an important implication in astrophysics.

关键词： quark-meson model nucleation false vacuum decay surface tension first-order phase transition

Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression

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Neural Regeneration Research 2025年第11期20卷 3259-3272页

作者： Huidong Li Faqin Li Zhaoyi Chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang Cheng Long School of Life Sciences South China Normal UniversityGuangzhouGuangdong ProvinceChina School of Life Sciences Guangzhou UniversityGuangzhouGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Major Obstetric Diseases The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina South China normal university-Panyu Central Hospital Joint Laboratory of Translational Medical Research Panyu Central HospitalGuangzhouGuangdong ProvinceChina

Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear ***(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B *** is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly *** studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like ***,the precise role of CYLD in glutamatergic neurons is largely ***,we first proposed involvement of CYLD in cued fear *** next constructed transgenic model mice with specific deletion of Cyld from glutamatergic *** results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male ***,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male ***,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial *** may contribute,at least in part,to cued fear expression.

关键词： basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission

Spiral wave chimeras in populations of oscillators coupled to a slowly varying diffusive environment

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Frontiers of physics 2023年第1期18卷 71-83页

作者： Lei Yang Yuan He Bing-Wei Li School of Physics Hangzhou Normal UniversityHangzhou 311121China

Chimera states are firstly discovered in nonlocally coupled oscillator *** a nonlocal coupling arises typically as oscillators are coupled via an external environment whose characteristic time scaleτis so small(i.e.,τ→0)that it could be eliminated ***,whether the chimera states still exist in the opposite situation(i.e.,τ≫1)is ***,by coupling large populations of Stuart–Landau oscillators to a diffusive environment,we demonstrate that spiral wave chimeras do exist in this oscillator-environment coupling system even whenτis very *** transitions such as from spiral wave chimeras to spiral waves or unstable spiral wave chimeras as functions of the system parameters are explored.A physical picture for explaining the formation of spiral wave chimeras is also *** existence of spiral wave chimeras is further confirmed in ensembles of FitzHugh–Nagumo oscillators with the similar oscillator-environment coupling *** results provide an affirmative answer to the observation of spiral wave chimeras in populations of oscillators mediated via a slowly changing environment and give important hints to generate chimera patterns in both laboratory and realistic chemical or biological systems.

关键词： spiral wave chimeras reaction-diffusion systems oscillator-environment coupling pattern formation

On p-variation of bifractional Brownian motion

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 127-141页

作者： WANG Wen-sheng Department of Mathematics Hangzhou Normal University Hangzhou 310036 China

In this paper we study p-variation of bifractional Brownian motion. As an applica-tion, we introduce a class of estimators of the parameters of a bifractional Brownian motion andprove that both of them are strongly consistent; as another application, we investigate fractalnature related to the box dimension of the graph of bifractional Brownian motion.

关键词： Bifractional Brownian motion variation strongly consistent fractal nature.