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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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Impact of Non-Compliance of Exposure Classes in Reinforced Concrete Structures
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作者 Serigne Touba Thiam Mouhamed Lamine Chérif Aidara Alinté Diatta 《Open Journal of Civil Engineering》 CAS 2023年第1期25-34,共10页
From the National Agency for the Organization and Construction of Infrastructures (ANOCI) program to the Emerging Senegal Plan (PSE), construction in Senegal has improved considerably. However, deficiencies remain in ... From the National Agency for the Organization and Construction of Infrastructures (ANOCI) program to the Emerging Senegal Plan (PSE), construction in Senegal has improved considerably. However, deficiencies remain in the specification of materials used mainly in hydraulic concrete. They are generally related to the specification of aggregates for alkali reactivity and the choice of exposure classes specified in NF EN 206-1. The purpose of this article is to study the incidence of non-compliance with exposure classes in reinforced concrete structures. To carry out this study, surveys were carried out at several sites (districts) in Dakar (Cité Avion, Touba Ouakam, Cité Asecna, Cité Batrain, Cité Comico, Cité Assemblée and Terme Sud) in order to collect information on the formulation and implementation methods used. The comparison of the various readings carried out made it possible to deduce conclusions and to give recommendations when using standard NF EN 206-1. 展开更多
关键词 Common Exposure classes Specific Exposure classes Concrete Alkali-Reaction
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Prioritised identification of structural classes of natural products from higher plants in the expedition of antimalarial drug discovery
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作者 Phanankosi Moyo Luke Invernizzi +5 位作者 Sephora M.Mianda Wiehan Rudolph Andrew W.Andayi Mingxun Wang Neil R.Crouch Vinesh J.Maharaj 《Natural Products and Bioprospecting》 CSCD 2023年第1期348-367,共20页
The emergence and spread of drug-recalcitrant Plasmodium falciparum parasites threaten to reverse the gains made in the fight against malaria.Urgent measures need to be taken to curb this impending challenge.The highe... The emergence and spread of drug-recalcitrant Plasmodium falciparum parasites threaten to reverse the gains made in the fight against malaria.Urgent measures need to be taken to curb this impending challenge.The higher plant-derived sesquiterpene,quinoline alkaloids,and naphthoquinone natural product classes of compounds have previously served as phenomenal chemical scaffolds from which integral antimalarial drugs were developed.Historical successes serve as an inspiration for the continued investigation of plant-derived natural products compounds in search of novel molecular templates from which new antimalarial drugs could be developed.The aim of this study was to identify potential chemical scaffolds for malaria drug discovery following analysis of historical data on phytochemicals screened in vitro against P.falciparum.To identify these novel scaffolds,we queried an in-house manually curated database of plant-derived natural product compounds and their in vitro biological data.Natural products were assigned to different structural classes using NPClassifier.To identify the most promising chemical scaffolds,we then correlated natural compound class with bioactivity and other data,namely(i)potency,(ii)resistance index,(iii)selectivity index and(iv)physicochemical properties.We used an unbiased scoring system to rank the different natural product classes based on the assessment of their bioactivity data.From this analysis we identified the top-ranked natural product pathway as the alkaloids.The top three ranked super classes identified were(i)pseudoalkaloids,(ii)naphthalenes and(iii)tyrosine alkaloids and the top five ranked classes(i)quassinoids(of super class triterpenoids),(ii)steroidal alkaloids(of super class pseudoalkaloids)(iii)cycloeudesmane sesquiterpenoids(of super class triterpenoids)(iv)isoquinoline alkaloids(of super class tyrosine alkaloids)and(v)naphthoquinones(of super class naphthalenes).Launched chemical space of these identified classes of compounds was,by and large,distinct from that of‘legacy’antimalarial drugs.Our study was able to identify chemical scaffolds with acceptable biological properties that are structurally different from current and previously used antimalarial drugs.These molecules have the potential to be developed into new antimalarial drugs. 展开更多
关键词 Natural products Compound classes PHYTOCHEMICALS Plasmodium falciparum Antiplasmodial drug resistance MALARIA Drug development
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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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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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AVERAGE ONESIDED WIDTHS OF SOBOLEV AND BESOV CLASSES
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作者 杨柱元 杨宗文 刘永平 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期148-160,共13页
The article concerns the average onesided widths of the Sobolev and Besov classes and the classes of functions with bounded moduli of smoothness. The weak asymptotic results are obtained for the corresponding quantities.
关键词 average onesided widths Sobolev classes Besov classes
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Characterization of Hereditary Rings ViaInjectivity and Projectivity Classes
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作者 于增海 段海生 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期27-30, ,共4页
In this note,some characterizations of hereditary rings using injectivity classes and projectivity classes are given.These results unify many well known results.
关键词 hereditary ring injectivity classes projectivity classes
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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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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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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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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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Integrating species and successional classes for wood production in a mixed forest restoration system in a neotropical region 被引量:1
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作者 Ananias Francisco Dias Junior Ana Lucia Martins Sodero Pincelli +4 位作者 Ana Paula Camara da Silva Alison Moreira da Silva Natalia Dias de Souza Mario Tommasiello Filho Jose Otavio Brito 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2313-2321,共9页
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow tre... As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow trees for wood production as an economic activity.The objective of this study was to quantify the increment of wood density of four forest species from different successional classes of a mixed system of restoration in a neotropical forest in Brazil.Tree discs were sampled at breast height and analyzed radially by X-ray densitometry to obtain apparent density and basic density.Three trees each of a species from the pioneer,early and late secondary successional stages and of the dominant species in the climax community.The radial profiles indicated increasing density from the pith to bark of trunks,except for some variations due to wood defects and growth.Average density was 0.576 g cm^(-3),0.655 g cm^(-3),0.706 g cm^(-3)and 0.775 g cm^(-3),respectively,for Peltophorum dubium,Schinus terebinthifolius,Cariniana estrellensis and Hymenaea courbaril.Radial profiles indicated higher amplitudes in the apparent densities for slow-growing species.X-ray densitometry generated parameters such as minimum,average and maximum densities,and radial density variations.These parameters are important for understanding the ecological functional role of successional classes of the Atlantic Forest from the Neotropical region. 展开更多
关键词 X-ray densitometry Timber species of neotropical forest Successional classes of forest species Maintenance of forest restoration
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EXACT SOLUTIONS FOR STATIONARY RESPONSES OF SEVERAL CLASSES OF NONLINEAR SYSTEMS TO PARAMETRIC AND/OR EXTERNAL WHITE NOISE EXCITATIONS 被引量:2
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作者 朱位秋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第2期165-175,共11页
The exact solutions for stationary responses of one class of the second order and three classes of higher order nonlinear systems to parametric and/or external while noise excitations are constructed by using Fokkcr-P... The exact solutions for stationary responses of one class of the second order and three classes of higher order nonlinear systems to parametric and/or external while noise excitations are constructed by using Fokkcr-Planck-Kolmogorov et/ualion approach. The conditions for the existence and uniqueness and the behavior of the solutions are discussed. All the systems under consideration are characterized by the dependence ofnonconservative fqrces on the first integrals of the corresponding conservative systems and arc catted generalized-energy-dependent f G.E.D.) systems. It is shown taht for each of the four classes of G.E.D. nonlinear stochastic systems there is a family of non-G.E.D. systems which are equivalent to the G.E.D. system in the sense of having identical stationary solution. The way to find the equivalent stochastic systems for a given G.E.D. system is indicated and. as an example, the equivalent stochastic systems for the second order G.E. D. nonlinear stochastic system are given. It is pointed out and illustrated with example that the exact stationary solutions for many non-G.E.D. nonlinear stochastic systems may he found by searching the equivalent G.E.D. systems. 展开更多
关键词 EXACT SOLUTIONS FOR STATIONARY RESPONSES OF SEVERAL classes OF NONLINEAR SYSTEMS TO PARAMETRIC AND/OR EXTERNAL WHITE NOISE EXCITATIONS
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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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Developing Pragmatic Competence in EFL Speaking Classes: From Theory to Practice 被引量:1
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作者 Yi Tao 《Sino-US English Teaching》 2004年第6期44-49,共6页
Fostering students' pragmatic competence in ESL/EFL classrooms has been the subject of a large number of studies over the last several decades. This paper will examine the importance of pragmatic competence in L2 spo... Fostering students' pragmatic competence in ESL/EFL classrooms has been the subject of a large number of studies over the last several decades. This paper will examine the importance of pragmatic competence in L2 spoken communication and investigate factors leading to pragmatic failures. It will also discuss possible ways to help foster students' pragmatic competence in EFL speaking classes. 展开更多
关键词 pragmatic competence pragmatic failures EFL speaking classes
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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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Research into the Application of Mind Map in English Intensive Reading Classes
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作者 黄丹艳 《海外英语》 2019年第9期255-256,共2页
Mind map has been widely recognized as an effective teaching and learning tool in all levels of education. This paper, based on the writer’s teaching practice, aimed to investigate the potential use of mind map in En... Mind map has been widely recognized as an effective teaching and learning tool in all levels of education. This paper, based on the writer’s teaching practice, aimed to investigate the potential use of mind map in English intensive reading classes of college students, and found that it could help students to understand and memorize the main ideas and important details of reading materials in a systematical way. 展开更多
关键词 MIND MAP ENGLISH INTENSIVE READING classes
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Promoting Learner Autonomy Through Reader- response Approach in EFL Literature Classes 被引量:1
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作者 TANG Hu 《海外英语》 2014年第5X期9-11,共3页
A number of methods and approaches have been practiced in recent communicative language teaching,the applying of the reader-response approach has seen the effectiveness in the EFL literature classes.Learner autonomy i... A number of methods and approaches have been practiced in recent communicative language teaching,the applying of the reader-response approach has seen the effectiveness in the EFL literature classes.Learner autonomy in EFL literature classes is reader’s ability to regard the reading text as his/her own both in the act of reading and after the act of reading. 展开更多
关键词 reader-response APPROACH EFL LITERATURE classes
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A Study on the improvement strategies to Effectiveness of Online Teaching and Learning in EFL Classes in College
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作者 王晶 《海外英语》 2020年第18期275-276,共2页
English online learning has been common trend in the world, how to teach and learn effectively in EFL classes through online environment is an urgent study. The purpose of the study to analyze the factors of affecting... English online learning has been common trend in the world, how to teach and learn effectively in EFL classes through online environment is an urgent study. The purpose of the study to analyze the factors of affecting the effectiveness of online teaching and learning in EFL classes in college. We build up a three-dimensional model in the perspective of teacher, learner and technology. And we propose the strategies of improving the effectiveness of online teaching and learning in EFL classes in college in the dimensions of teacher, learner and technology. 展开更多
关键词 improvement strategies the effectiveness of online teaching and learning EFL classes in college
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