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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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Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature 被引量:1
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作者 Tong Lu Li Mei +2 位作者 Bao-Chao Li Zi-Wei Huang Huang Li 《World Journal of Clinical Cases》 SCIE 2024年第2期431-442,共12页
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or... BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases. 展开更多
关键词 Temporomandibular disorder Skeletal class II Deep overbite Dual bite Invisible mandibular advancement appliance Case report
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Existence of Two Limit Cycles in Zeeman’s Class 30 for 3D Lotka-Volterra Competitive System
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作者 Yaoqi Li 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1584-1590,共7页
Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which ... Gyllenberg and Yan(Discrete Contin Dyn Syst Ser B 11(2):347–352,2009)presented a system in Zeeman’s class 30 of 3-dimensional Lotka-Volterra(3D LV)competitive systems to admit at least two limit cycles,one of which is generated by the Hopf bifurcation and the other is obtained by the Poincaré-Bendixson theorem.Yu et al.(J Math Anal Appl 436:521–555,2016,Sect.3.4)recalculated the first Liapunov coefficient of Gyllenberg and Yan’s system to be positive,rather than negative as in Gyllenberg and Yan(2009),and pointed out that the Poincaré-Bendixson theorem is not applicable for that system.Jiang et al.(J Differ Equ 284:183–218,2021,p.213)proposed an open question:“whether Zeeman’s class 30 can be rigorously proved to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem?”This paper provides four systems in Zeeman’s class 30 to admit at least two limit cycles by the Hopf theorem and the Poincaré-Bendixson theorem and gives an answer to the above question. 展开更多
关键词 3-dimensional Lotka-Volterra(3D LV)competitive system Zeeman’s class 30 Fine focus Hopf bifurcation Poincaré-Bendixson theorem Limit cycle
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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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World Class Elite Breaststrokers Downward Kick EMG Muscle Activity of the Gluteus Maximus, Quadriceps Femoris, Hamstring, Gastrocnemius Medialis, Rectus Abdominal, and Erector Spinae
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作者 Takahisa Ide William F.Johnson +10 位作者 Sadafumi Takise Noriko Inada Hiromasa Fujimori Takeharu Fujimori Emi Moronuki Ai Soma Kazuki Watanabe Asahi Nagahata Iryna Glavnyk Mark Nikolaev Bogdan Plavin 《Psychology Research》 2024年第2期64-69,共6页
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua... This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke. 展开更多
关键词 swimming breaststroke downward kick EMG imagination world class elite swimmers
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Analysis of the Energy and Environmental Sustainability of a Built Space System: The Case of Patte d’Oie University Campus in Ouagadougou
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作者 Daouda Sawadogo Ousmane Coulibaly +1 位作者 Xavier Chesneau Belkacem Zeghmati 《Energy and Power Engineering》 2024年第5期197-215,共19页
The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and... The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and modeling tool, supported by various methodological references, formed the basis of our approach. Adopting a systemic perspective, we described the structural and functional aspects of the systems making up built spaces, as well as the associated energy flows. Our approach was also based on a typology, taking into account typical days, structural and functional configurations at different scales and angles of observation. The analysis tool we developed in Java was applied to the built space system of the Patte d’Oie university campus in Ouagadougou. Annual electricity consumption was measured at 124387.34 kWh, closely aligned with the average annual electricity bill (125224.31 kWh), with a maximum relative deviation of 1%, followed by a carbon emission balance of 58337.66 kg eq CO<sub>2</sub> per year. This validation confirmed the effectiveness of our tool. In addition, following the analysis of electricity consumption using our tool, the university campus was classified in energy class B and environmental class C. These results will be based on the emission factors of the energy mix of the West African Economic and Monetary Union (WAEMU) territory, with particular emphasis on Burkina Faso. 展开更多
关键词 Energy Function Energy class Carbon Footprint Built Space Consumption Item systemic Approach Typological Approach
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The Integration Strategy of Class Teacher Management and Mathematics Teaching
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作者 Chao Wen 《Journal of Contemporary Educational Research》 2024年第6期142-147,共6页
The professional and moral education of high school mathematics teachers will make classroom management work better,but their work pressure will also lead to classroom management problems.To do a good job in high scho... The professional and moral education of high school mathematics teachers will make classroom management work better,but their work pressure will also lead to classroom management problems.To do a good job in high school class teacher management and organically integrate it with mathematics teaching,we need to start from two aspects:mathematics teaching class teachers and class teacher work teaching,and penetrate mathematical thinking into daily classroom management,moral education,and classroom culture construction.Based on the attributes of the subject,we guide high school students to reflect after class to stimulate their self-management initiative through the cultivation of qualified class representatives.In addition,it is necessary to skillfully resolve classroom generative problems,change the roles of teachers and students,and integrate classroom management with mathematics teaching. 展开更多
关键词 High school class teacher class teacher management Mathematics teaching Integration strategies
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基于CLASS促进幼儿教师提升师幼互动能力的策略
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作者 龚方刚 《小学教学研究》 2024年第8期92-93,96,共3页
师幼互动是学前教育课程实施的主要过程,也是学前儿童在幼儿园一日活动中的生活体验、学习体验和情感体验的重要载体。师幼互动的质量对学前教育的质量起决定性作用。CLASS(课堂评价评分系统)不仅可以用来评价课堂师幼互动的质量,还可... 师幼互动是学前教育课程实施的主要过程,也是学前儿童在幼儿园一日活动中的生活体验、学习体验和情感体验的重要载体。师幼互动的质量对学前教育的质量起决定性作用。CLASS(课堂评价评分系统)不仅可以用来评价课堂师幼互动的质量,还可以用于提升教师师幼互动的能力。基于CLASS,文章提出了一系列提升教师师幼互动能力的相关策略。 展开更多
关键词 教师专业发展 幼儿教师 class 师幼互动
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幼儿园体育活动中师幼互动质量分析及策略研究——基于ClASS课堂互动评估系统的观察分析
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作者 李化树 骆倩 《福建教育》 2023年第47期18-22,共5页
本研究以ClASS课堂互动评估系统为测量工具,对M市6所幼儿园的31个体育集体教学活动视频进行反复观察,以“情感支持”“班级管理”“教育支持”三个维度为切入点,对案例中的师幼互动质量进行评分和分析,揭示当前幼儿园体育活动中师幼互... 本研究以ClASS课堂互动评估系统为测量工具,对M市6所幼儿园的31个体育集体教学活动视频进行反复观察,以“情感支持”“班级管理”“教育支持”三个维度为切入点,对案例中的师幼互动质量进行评分和分析,揭示当前幼儿园体育活动中师幼互动水平。研究结果显示,幼儿园体育活动中师幼互动质量整体上处于中上水平;师幼互动各维度间存在相关性、交融性;不同组织形式的体育活动师幼互动质量存在显著差异。在此基础上,提出相关建议院关注情感支持,构建平等亲密的师幼关系;优化教育行为,营造良好的体育活动生态;重视教育支持,促进幼儿高阶思维发展。 展开更多
关键词 体育活动 师幼互动质量 class课堂互动评估系统
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Prevalence of angle class III malocclusion: A systematic review and meta-analysis 被引量:15
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作者 Daniel K. Hardy Yltze P. Cubas Maria F. Orellana 《Open Journal of Epidemiology》 2012年第4期75-82,共8页
Objective: This study seeks to review current and relevant literature on global Angle class III malocclusion prevalence. Materials and Methods: The electronic databases PubMed, ISI Web of Knowledge, and the Cochrane D... Objective: This study seeks to review current and relevant literature on global Angle class III malocclusion prevalence. Materials and Methods: The electronic databases PubMed, ISI Web of Knowledge, and the Cochrane Database of Systematic Review were searched using specific inclusion criteria to obtain applicable articles. All pertinent references were also examined for acceptability. Results: A total of 20 articles were identified using the inclusion criteria. The prevalence of Angle class III malocclusion ranged from 0 to 26.7% in different populations reported in the literature examined. Meta-regression analysis showed no statistically significant association between prevalence rates and the method of assessment, age group and year of the study. However, much of the study-to-study variation (approximately 40%) could be explained by population. Conclusion: These results suggest that the prevalence of Angle class III malocclusion varies greatly within different races and geographic regions. Chinese and Malaysian populations have a higher prevalence of Angle class III malocclusion compared to other racial groups, while Indian populations have a lower prevalence than all other racial groups examined. 展开更多
关键词 MALOCCLUSION class III PREVALENCE systematic REVIEW META-ANALYSIS
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Classification and Net Primary Productivity of the Southern China's Grasslands Ecosystem Based on Improved Comprehensive and Sequential Classification System(CSCS) Approach 被引量:6
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作者 SUN Zheng-guo SUN Cheng-ming +2 位作者 ZHOU Wei JU Wei-min LI Jian-long 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期893-903,共11页
This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed ... This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed 5 thermal grades and 6 humidity grades. Four classes of grasslands vegetation were recognized by improved CSCS, namely, tundra grassland class, typical grassland class, mixed grassland class and alpine grassland class. At the type level, 14 types of vegetations (9 grasslands and 5 forests) were classified. The NPP had a trend to decrease from east to west and south to north, and the annual mean NPP was estimated to be 656.3 g C m-2 yr-1. The NPP value of alpine grassland class was relatively high, generally more than 1200 g C m2 yr-1. The NPP value of mixed grassland class was in a range from 1 000 to 1200 g C m-2 yr-1. Tundra grassland class was located in southeastern Tibet with high elevation, and its NPP value was the lowest (〈600 g C m'2yrl). The typical grassland class distributed in most of the area, and its NPP value was generally from 600 to 1000 g C m-2 yr-1. The total NPP value in the study area was 68.46 Tg C. The NPP value of typical grassland class was the highest (48.44 Tg C), and mixed grassland class was the second (16.54 Tg C), followed by alpine grassland class (3.22 Tg C), with tundra grassland class being the lowest (0.25 Tg C). For all the grasslands types, the total NPP of forest meadow was the highest (34.81 Tg C), followed by sparse forest brush (16.54 Tg C), and montane meadow was the lowest (0.01 Tg C). 展开更多
关键词 improved CSCS hydro-thermal pattern southem China grasslands classes and types net primary productivity (NPP)
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N SOLITON SOLUTION FOR A CLASS OF THE SYSTEM OF LS NONLINEAR WAVE INTERACTION 被引量:4
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作者 GUO Boling PAN Xiude 《Chinese Physics Letters》 SCIE CAS CSCD 1990年第6期241-244,共4页
In this note,the explicit form of the N soliton solutions for a class of the system of LS nonlinear wave interaction have been obtained by using Hirota's method.
关键词 METHOD class SOLITON
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Attributes reduct and decision rules optimization based on maximal tolerance classification in incomplete information systems with fuzzy decisions 被引量:1
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作者 Fang Yang Yanyong Guan +1 位作者 Shujin Li Lei Du 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期995-999,共5页
A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classe... A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classes, and fuzzy approximations are defined based on them. Three types of relative reducts of maximal tolerance classes are then proposed, and three types of fuzzy decision rules based on the proposed attribute description are defined. The judgment theorems and approximation discernibility functions with respect to them are presented to compute the relative reduct by using Boolean reasoning techniques, from which we can derive optimal fuzzy decision rules from the systems. At last, three types of relative reducts of the system and their computing methods are given. 展开更多
关键词 rough sets information systems maximal tolerance class attribute reduct decision rules.
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EXISTENCE AND NONEXISTENCE FOR THE INITIAL BOUNDARY VALUE PROBLEM OF ONE CLASS OF SYSTEM OF MULTIDIMENSIONAL NONLINEAR SCHRDINGER EQUATIONS WITH OPERATOR AND THEIR SOLITON SOLUTIONS 被引量:3
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作者 郭柏灵 《Acta Mathematica Scientia》 SCIE CSCD 1989年第1期45-56,共12页
The nonlinear interactions between the monochromatic wave have been considered by K. Matsunchi, who also proposed one class of the nonlinear Schrdinger equation system with wave operator. We also obtain the same type ... The nonlinear interactions between the monochromatic wave have been considered by K. Matsunchi, who also proposed one class of the nonlinear Schrdinger equation system with wave operator. We also obtain the same type of equations, which are satisfied by transverse velocity of higher frequency electron, as we study soliton in plasma physics. In this paper, under some condition we study the existence and nonexistence for this equations in the cases possessing different signs in nonlinear term. 展开更多
关键词 DINGER EQUATIONS WITH OPERATOR AND THEIR SOLITON SOLUTIONS EXISTENCE AND NONEXISTENCE FOR THE INITIAL BOUNDARY VALUE PROBLEM OF ONE class OF system OF MULTIDIMENSIONAL NONLINEAR SCHR
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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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小学低学段语文优质课堂师生互动特征研究--基于CLASS 课堂评价打分系统的分析
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作者 高振宇 占紫蓉 《北京教育学院学报》 2023年第4期36-47,共12页
采用美国弗吉尼亚大学研究团队开发的课堂评价打分系统(CLASS),围绕情感支持、课堂组织、教学支持三个领域及下设的十个维度,对20节小学低学段语文优质课堂的师生互动状况进行深度观察,探索优质课堂环境下师生互动的整体水平及各维度之... 采用美国弗吉尼亚大学研究团队开发的课堂评价打分系统(CLASS),围绕情感支持、课堂组织、教学支持三个领域及下设的十个维度,对20节小学低学段语文优质课堂的师生互动状况进行深度观察,探索优质课堂环境下师生互动的整体水平及各维度之间的相互关系,并综合量化数据和质性分析得出研究结论。研究发现,小学低学段语文优质课堂在情感支持方面,能较好地激发教师的职业热情,并培养学生自主自立的精神与能力;在课堂组织方面,能以课堂实效为目标,创设高品质的教学活动;在教学支持方面,能营造安全的思维环境,促进师生深度互动。 展开更多
关键词 师生互动 语文优质课 课堂评价打分系统 小学语文
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NECESSARY AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM 被引量:1
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作者 刘德明 《Acta Mathematica Scientia》 SCIE CSCD 1991年第1期65-71,共7页
In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We ... In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We prove that (1) possesses at most one limit cycle and give out the necessary and sufficient conditions of existence and uniqueness of limit cycles. 展开更多
关键词 NECESSARY AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A class OF POLYNOMIAL system LIM
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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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Orthodontic-surgical treatment for severe skeletal class Ⅱ malocclusion with vertical maxillary excess and four premolars extraction: A case report 被引量:2
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作者 Yi-Wen Zhou Yan-Yi Wang +3 位作者 Zhi-Feng He Ming-Xing Lu Gui-Feng Li Huang Li 《World Journal of Clinical Cases》 SCIE 2023年第5期1106-1114,共9页
BACKGROUND Patient satisfaction with facial appearance at the end of orthodontic camouflage treatment is very important, especially for skeletal malocclusion. This case report highlights the importance of the treatmen... BACKGROUND Patient satisfaction with facial appearance at the end of orthodontic camouflage treatment is very important, especially for skeletal malocclusion. This case report highlights the importance of the treatment plan for a patient initially treated with four-premolar-extraction camouflage, despite indications for orthognathic surgery.CASE SUMMARY A 23-year-old male sought treatment complaining about his unsatisfactory facial appearance. His maxillary first premolars and mandibular second premolars had been extracted, and a fixed appliance had been used to retract his anterior teeth for two years without improvement. He had a convex profile, a gummy smile, lip incompetence, inadequate maxillary incisor inclination, and almost a class I molar relationship. Cephalometric analysis showed severe skeletal class Ⅱ malocclusion(A point-nasion-B point = 11.5°) with a retrognathic mandible(sella-nasion-B point = 75.9°), a protruded maxilla(sella-nasion-A point = 87.4°), and vertical maxillary excess(upper incisor to palatal plane = 33.2 mm). The excessive lingual inclination of the maxillary incisors(upper incisor to nasion-A point line =-5.5°)was due to previous treatment attempts to compensate for the skeletal class Ⅱ malocclusion. The patient was successfully retreated with decompensating orthodontic treatment combined with orthognathic surgery. The maxillary incisors were repositioned and proclined in the alveolar bone, the overjet was increased, and a space was created for orthognathic surgery, including maxillary impaction, anterior maxillary back-setting, and bilateral sagittal split ramus osteotomy to correct his skeletal anteroposterior discrepancy. Gingival display was reduced, and lip competence was restored. In addition, the results remained stable after 2 years. The patient was satisfied with his new profile as well as with the functional malocclusion at the end of treatment.CONCLUSION This case report provides orthodontists a good example of how to treat an adult with severe skeletal class Ⅱ malocclusion with vertical maxillary excess after an unsatisfactory orthodontic camouflage treatment. Orthodontic and orthognathic treatment can significantly correct a patient’s facial appearance. 展开更多
关键词 Case report Skeletal classⅡmalocclusion Vertical excess Gummy smile Camouflage treatment Orthognathic surgery
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Infl uence of altitude and tree class on climate-growth relationships in a larch plantation in subtropical China 被引量:1
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作者 Chunyan Wu Dongsheng Chen +1 位作者 Xiaomei Sun Shougong Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1869-1880,共12页
Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains ... Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships. 展开更多
关键词 Tree-ring width index CHRONOLOGY Correlation coeffi cient Additive mixed models Tree classes
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