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Extensive numerical simulations on competitive growth between the Edwards–Wilkinson and Kardar–Parisi–Zhang universality classes
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作者 余成志 刘潇 +1 位作者 唐军 夏辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期298-307,共10页
Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and K... Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and Kardar–Parisi–Zhang(KPZ) universality classes, respectively. The linear growth systems include the EW equation and the model of random deposition with surface relaxation(RDSR), the nonlinear growth systems involve the KPZ equation and typical discrete models including ballistic deposition(BD), etching, and restricted solid on solid(RSOS). The scaling exponents are obtained in both the(1 + 1)-and(2 + 1)-dimensional competitive growth with the nonlinear growth probability p and the linear proportion 1-p. Our results show that, when p changes from 0 to 1, there exist non-trivial crossover effects from EW to KPZ universality classes based on different competitive growth rules. Furthermore, the growth rate and the porosity are also estimated within various linear and nonlinear growths of cooperation and competition. 展开更多
关键词 competitive growth scaling behavior discrete growth model Kardar–Parisi–Zhang universality class
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A Case Study on the Effectiveness of Pre-Class Activities in Higher Vocational English Classes: Taking Pingliang Vocational and Technical College as an Example
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作者 Liuna Yang 《Journal of Contemporary Educational Research》 2024年第8期233-237,共5页
Based on Bloom’s“effective teaching theory,”this paper proposes pre-class activities to improve students’enthusiasm and autonomy in English learning.These include sentence construction,situational dubbing,famous q... Based on Bloom’s“effective teaching theory,”this paper proposes pre-class activities to improve students’enthusiasm and autonomy in English learning.These include sentence construction,situational dubbing,famous quotes,English songs,English games,Chinese stories,regional cultures,and theme debates,which combine life,interest,and inspiration as the main characteristics.The activities can enhance the sense of participation and achievement of all students to achieve the purpose of effective teaching. 展开更多
关键词 Higher vocational college English class Pre-class activity EFFECTIVENESS
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Teaching Large, Heterogeneous English Classes in High School:Some Practical Principles 被引量:1
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作者 雷琨 《海外英语》 2015年第8期21-22,共2页
Teaching large,heterogeneous English class is now a teaching fact in China.It brings a lot of practical problems to English teachers who teach that kind of class because of the existence of differences among learners.... Teaching large,heterogeneous English class is now a teaching fact in China.It brings a lot of practical problems to English teachers who teach that kind of class because of the existence of differences among learners.This paper aims to provide practical principles illustrated by some scholars to address problems appeared in those classes and achieve the aim of better learning for all members of the class. 展开更多
关键词 LARGE class HETEROGENEOUS class TEACHING PRINCIPLES
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On n-K Width of Certain Function Classes Defined by Linear Differential Operators in L_2 Space
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作者 吴嘎日迪 包那 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第4期27-31, ,共5页
Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates... Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates of the n K width d n(W M(A),L 2[0,1]) . 展开更多
关键词 linear operator smooth function class WIDTH
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On n-K Width of Certain Function Classes Defined by Linear Differential Operators in L2 Space 被引量:2
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作者 吴嘎日迪 包那 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第4期27-31,共页
Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates... Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates of the n K width d n(W M(A),L 2[0,1]) . 展开更多
关键词 linear operator smooth function class WIDTH
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Effective Language Teaching in Large Classes
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作者 张丽丽 《语言与文化研究》 2010年第1期115-118,共4页
With more and more people who are jumping into the line of learning the second language (especially English),and also due to the limited resources in language teaching,many foreign language teachers are nowadays confr... With more and more people who are jumping into the line of learning the second language (especially English),and also due to the limited resources in language teaching,many foreign language teachers are nowadays confronting the large classes when teaching.So how to teach foreign language effectively in large classes has become an issue as well as a special field to make researches in. 展开更多
关键词 LANGUAGE TEACHING LARGE classes suggestions
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On management of college English teaching of big classes
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作者 郑冬临 《Sino-US English Teaching》 2007年第11期35-38,共4页
In recent years, the scale of enrollment of college students has been expanded. As a result, in colleges teachers are badly needed for the basic course of college English. To solve this problem, big classes are adopte... In recent years, the scale of enrollment of college students has been expanded. As a result, in colleges teachers are badly needed for the basic course of college English. To solve this problem, big classes are adopted for college English teaching in some universities. And scientific management can guarantee the quality of college English teaching of big classes. Finally, this article introduces four tactics to manage college English teaching of big classes. 展开更多
关键词 college English teaching of big classes teaching management
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A Brief Report on Task-based Translation Teaching in University English Classes in China
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作者 王景怿 《海外英语》 2016年第18期141-142,共2页
Translation teaching in college English classes is highly teacher-centered, so students are not fully motivated and therefore lack basic interests to fulfill these tasks. In order for students to be more involved and ... Translation teaching in college English classes is highly teacher-centered, so students are not fully motivated and therefore lack basic interests to fulfill these tasks. In order for students to be more involved and more learning independent, translation teaching needs to become student-centered and task-based. This paper discusses the theoretical basis of this teaching method and suggests possible ways to use the method. 展开更多
关键词 translation teaching TASK-BASED college English class
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PAD Class教学模式对英语专业学生写作焦虑影响的实证研究
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作者 王颖 《外国语文》 北大核心 2024年第2期197-206,共10页
本研究以英语专业大一120名学生为实验对象,进行了为期16周的实证研究,以探讨PAD class教学模式对英语专业学生写作焦虑的影响。基于《二语写作焦虑量表》调查问卷结果表明:英语专业学生总体焦虑处于中等焦虑水平,PAD Class能有效降低... 本研究以英语专业大一120名学生为实验对象,进行了为期16周的实证研究,以探讨PAD class教学模式对英语专业学生写作焦虑的影响。基于《二语写作焦虑量表》调查问卷结果表明:英语专业学生总体焦虑处于中等焦虑水平,PAD Class能有效降低学生的写作总体焦虑,其中课堂焦虑、构思焦虑、自信焦虑明显降低,但回避焦虑没有达到显著水平;PAD Class模式对高中低不同写作水平学生的写作焦虑都有影响,对中、低水平学生的写作焦虑缓解比对高水平学生的影响效果更明显。 展开更多
关键词 PAD class 英语专业写作 写作焦虑 实证研究
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The Effective Approach to Interactive English Classes --- Group Work 被引量:1
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作者 姜洁 周华 《Sino-US English Teaching》 2006年第4期5-7,共3页
A series of study and investigation has been made on the basis of the theory of group work. The purpose is to study the effectiveness of group work in the interaction class, thus to attract more English teachers' att... A series of study and investigation has been made on the basis of the theory of group work. The purpose is to study the effectiveness of group work in the interaction class, thus to attract more English teachers' attention to seek for the new approach to the breakthrough of traditional English class mode. 展开更多
关键词 group work interaction class EFFECTIVENESS
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n-tilting Torsion Classes and n-cotilting Torsion-free Classes 被引量:2
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作者 HE Dong-lin LI Yu-yan 《Chinese Quarterly Journal of Mathematics》 2019年第2期196-203,共8页
In this paper,we consider some generalizations of tilting torsion classes and cotilting torsion-free classes,give the definition and characterizations of n-tilting torsion classes and n-cotilting torsion-free classes,... In this paper,we consider some generalizations of tilting torsion classes and cotilting torsion-free classes,give the definition and characterizations of n-tilting torsion classes and n-cotilting torsion-free classes,and study n-tilting preenvelopes and n-cotilting precovers. 展开更多
关键词 n-tilting TORSION classes n-cotilting TORSION-FREE classes preenvelopes precovers
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Heterotic Classes and Utilization Patterns in Chinese Foxtail Millet [<i>Setaria italica</i>(L.) P. Beauv] 被引量:7
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作者 Zhengli Liu Guihua Bai +3 位作者 Dadong Zhang Chengsong Zhu Xiaoli Ren Suying Li 《Agricultural Sciences》 2014年第14期1392-1406,共15页
Utilization of heterosis to develop hybrid cultivars can significantly increase yield of most crops including foxtail millet. However, previous foxtail millet hybrid cultivars have been largely developed from crosses ... Utilization of heterosis to develop hybrid cultivars can significantly increase yield of most crops including foxtail millet. However, previous foxtail millet hybrid cultivars have been largely developed from crosses between sterile lines and conventional varieties or between sterile lines and varieties that are geographically distent from the sterile lines. The research on classification of heterotic classes and determinetaion of heterotic patterns has not been reported, which results in uncertainty in selection of parents for crosses and delays progress in utilization of high yielding hybrids in large-scale commercial production. In this study, a core collection of 128 accessions from China was grouped into six classes using combined analyses of population structure, pedigree, and clustering. The classification was conducted based mainly on molecular clustering of genotypic data, also considered the population structure and mathematical clustering using phenotypic data, and was finally validated through pedigree analysis. According to the transgressive and superstandard heterosis for grain yield, plant height, panicle length, panicle diameter, single panicle weight, grain weight per panicle, and 1000-grain weight collected from an incomplete-diallel-cross experiment, we identified six superior heterosis patterns (C2/C1, C2/C4, C2/C5, C2/C6, C1/C5 and C4/C5) and four inferior heterosis patterns (C1/C3, C1/C4, C1/C6 and C4/C6), and explored their potential applications in millet hybrid breeding. This study laid a foundation for effective use of foxtail millet heterosis in improving millet hybrid yield. 展开更多
关键词 Foxtail MILLET Heterotic classes Heterotic Pattern Molecular Clustering POPULATION Structure
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On the Symmetry Classes of Functions 被引量:1
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作者 ZHU Ping~1,2, FAN Yun~3 1. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 2. School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China 3. School of Mathematics and Statistics, Huazhong Normal University, Wuhan 430079, Hubei, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第5期813-816,共4页
Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several... Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes. 展开更多
关键词 symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent
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Effective Ways to Improve Students'Interests in English Classes
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作者 彭茜茜 《海外英语》 2013年第10X期70-71,74,共3页
Interest is the key role in English learning. Thus, English teachers should take effective ways to raise students'interests in teaching classes. Scientific investigation has proved that using effective approaches ... Interest is the key role in English learning. Thus, English teachers should take effective ways to raise students'interests in teaching classes. Scientific investigation has proved that using effective approaches certainly helps arousing students'interests in English teaching. 展开更多
关键词 ENGLISH learning INTEREST teaching WAYS ENGLISH CL
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Needs Analysis of English Culture Background Introduction in Spoken English Classes
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作者 王丛丛 《海外英语》 2013年第2X期54-56,共3页
With globalization there is an increasing need for spoken English for Chinese college students. However, the situation of the teaching system of spoken English in most universities in China is not satisfactory. Influe... With globalization there is an increasing need for spoken English for Chinese college students. However, the situation of the teaching system of spoken English in most universities in China is not satisfactory. Influenced by the exam-oriented teaching system, great importance has been put on English grammar and the skills of reading and writing. As a result, students'enthusiasm in improving their spoken English is diminished. Actually, students need some knowledge about English culture background before they can communicate effectively. It is significant for teachers to find out the students'wants and lacks during their spoken English study. Besides, attentions should be paid to English culture background in spoken English classes by both teachers and students. This paper mainly aimed at finding out the needs of students for English culture background in spoken English classes based on the theory of needs analysis. 展开更多
关键词 needs analysis ENGLISH CULTURE BACKGROUND SPOKEN E
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THE N-WIDTHS FOR A GENERALIZED PERIODIC BESOV CLASSES 被引量:1
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作者 许贵桥 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期663-671,共9页
In this paper, an extension of Besov classes of periodic functions on Td is given. The weak asymptotic results concerning the Kolmogorov n-widths, the linear n-widths, and the Gel'fand n-widths are obtained, respecti... In this paper, an extension of Besov classes of periodic functions on Td is given. The weak asymptotic results concerning the Kolmogorov n-widths, the linear n-widths, and the Gel'fand n-widths are obtained, respectively. 展开更多
关键词 Generalized Besov classes approximation n-widths
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WIDTHS AND AVERAGE WIDTHS OF SOBOLEV CLASSES 被引量:1
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作者 刘永平 许贵桥 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期178-184,共7页
This paper concerns the problem of the Kolmogorov n-width, the linear re-width, the Gel'fand n-width and the Bernstein re-width of Sobolev classes of the periodic multivariate functions in the space Lp(Td) and the... This paper concerns the problem of the Kolmogorov n-width, the linear re-width, the Gel'fand n-width and the Bernstein re-width of Sobolev classes of the periodic multivariate functions in the space Lp(Td) and the average Bernstein o-width, average Kolmogorov o-widths, the average linear o-widths of Sobolev classes of the multivariate functions in the space LP(R ), where p = (p1,…,pd), 1 < Pj < ∞o, j = 1,2,…,d, or pj = ∞,j = 1,2,…, d. Their weak asymptotic behaviors are established for the corresponding quantities. 展开更多
关键词 Multivariate function Sobolev class WIDTH average width
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RELATIVE WIDTH OF SMOOTH CLASSES OF MULTIVARIATE PERIODIC FUNCTIONS WITH RESTRICTIONS ON ITERATED LAPLACE DERIVATIVES IN THE L_2-METRIC 被引量:1
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作者 刘永平 杨连红 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期720-728,共9页
For two subsets W and V of a Banach space X, let Kn(W, V, X) denote the relative Kolmogorov n-width of W relative to V defined by Kn(W,V,X):=inf sup inf/Ln f∈W g∈V∩Ln‖f-g‖x, where the infimum is taken over ... For two subsets W and V of a Banach space X, let Kn(W, V, X) denote the relative Kolmogorov n-width of W relative to V defined by Kn(W,V,X):=inf sup inf/Ln f∈W g∈V∩Ln‖f-g‖x, where the infimum is taken over all n-dimensional linear subspaces Ln of X. Let W2(△^τ) denote the class of 2π-periodic functions f with d-variables satisfying ∫[-π, π]^d|△^τf(x)|^2dx≤1, while △^τ is the r-iterate of Laplace operator △. This article discusses the relative Kolmogorov n-width of W2(△^τ) relative to W2(△^τ) in Lq([-π, π]^d) (1≤ q ≤ ∞), and obtain its weak asymptotic result. 展开更多
关键词 Multivariate function classes WIDTH relative width
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On n-K Width of Certain Function Classes Defined by Linear Operators in L_2 Space 被引量:1
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作者 YU Rui-fang WU Ga-ridi 《Chinese Quarterly Journal of Mathematics》 2016年第1期96-101,共6页
Let M(u) be an N-function, L_r(f, x) and K_r(f, x) are Bak operator and Kantorovich operator, W_M(L_r(f)) and W_M(K_r(f)) are the Sobolev-Orlicz classes defined by L_r(f, x), K_r(f, x) and M(u). In this paper we give ... Let M(u) be an N-function, L_r(f, x) and K_r(f, x) are Bak operator and Kantorovich operator, W_M(L_r(f)) and W_M(K_r(f)) are the Sobolev-Orlicz classes defined by L_r(f, x), K_r(f, x) and M(u). In this paper we give the asymptotic estimates of the n-K widths d_n(W_M(L_r(f)), L_2[0, 1]) and d_n(W_M(K_r(f)), L_2[0, 1]). 展开更多
关键词 linear operator Sobolev-Orlicz class WIDTH
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Muntz Rational Approximation for Special Function Classes in Orlicz Spaces 被引量:1
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作者 Ruifang Yu Garide Wu 《Analysis in Theory and Applications》 CSCD 2017年第1期20-28,共9页
Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of th... Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of these classes under widely con- ditions. Because of the Orlicz Spaces is bigger than continuous function space and the Lp space, so the results of this paper has a certain expansion significance. 展开更多
关键词 Muntz rational approximation bounded variation function class Sobolev functionclass Orlicz space.
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