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Evaluate and Suggest Evidence for the Relationship between Attainment and Learner Variables
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作者 贾颖 《语言与文化研究》 2010年第1期88-96,共9页
English as a popular foreign language in China is learned by many students.The attainment is often considered and talked.There are many factors which affect the learning outcomes. This essay will give a brief introduc... English as a popular foreign language in China is learned by many students.The attainment is often considered and talked.There are many factors which affect the learning outcomes. This essay will give a brief introduction of the aspects concerning the evidence for the relationship between attainment and learner variables. 展开更多
关键词 MOTIVATION strategies attainment learning
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Applying SMART Goal Intervention Leads to Greater Goal Attainment, Need Satisfaction and Positive Affect
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作者 Zeynab Bahrami Atena Heidari Jacquelyn Cranney 《International Journal of Mental Health Promotion》 2022年第6期869-882,共14页
Previous research suggests that planning interventions lead to increased goal attainment, while other researchsuggests that goal attainment leads to increased well-being. This research integrates these two sets of res... Previous research suggests that planning interventions lead to increased goal attainment, while other researchsuggests that goal attainment leads to increased well-being. This research integrates these two sets of researchfindings by investigating the effectiveness of one goal planning intervention, the SMART goal program, on goalattainment, and thus need satisfaction and well-being, in university students. An experimental design across aone-week period was employed to test whether participants in the experimental group, who received the SMARTgoal instructions, better obtained their goal in comparison to control group participants who did not receive thosespecific instructions. Findings indicated that the SMART goal program led to greater rated goal attainment andneed satisfaction, but not greater subjective well-being (SWB). Nevertheless, one component of SWB, positiveaffect, was greater in the Experimental group. Type of individually chosen self-concordant goal content hadno impact on whether participants attained their goal. 展开更多
关键词 SMART goal intervention goal attainment need satisfaction subjective well-being positive affect
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Enhancing the Students’ Rhetoric Attainments in Teaching of College English Intensive Reading
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作者 ZHANG Rong-gen 《Sino-US English Teaching》 2019年第7期300-305,共6页
Beginning with various definitions of rhetoric, the paper gives a survey of some common English rhetoric figures found in College English intensive reading, such as metaphor, simile, transferred epithet, allusion, hyp... Beginning with various definitions of rhetoric, the paper gives a survey of some common English rhetoric figures found in College English intensive reading, such as metaphor, simile, transferred epithet, allusion, hyperbole, personification, metonymy, antithesis, onomatopoeia, double negative, inversion, rhetoric question, parady, transferred negation, and the like. By elaborating the functions of those rhetoric figures, the paper attempts to enhance the students’ rhetoric attainments and arouse their interest in learning English. 展开更多
关键词 RHETORIC attainmentS RHETORIC FIGURES COLLEGE English TEACHING
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Narrowing the Attainment Gap through Parental Engagement
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作者 Bingying Gao 《Review of Educational Theory》 2020年第3期96-100,共5页
Based on the selected policy of Scotland Delivering Excellence and Equity in Scottish Education(2016a)with its context in related concepts and literature support.This essay will focus on the engagement of parents as a... Based on the selected policy of Scotland Delivering Excellence and Equity in Scottish Education(2016a)with its context in related concepts and literature support.This essay will focus on the engagement of parents as a part of narrowing the attainment gap with socio-economic and political factors and what is provided by schools to promote social commitment and achieving equity during the Scottish education process.Critically analysis and reflection of the policy implementation and the way to look forward.As for the main part,the author explains what attainment and attainment gap is,the aim of the policy and discusses the reasonable of the policy through offered evidence.Following the interpretation of“policy as discourse”approach,and whereby how will the Scottish Government and Education Scotland support children and families to closing the attainment gap in this policy.The theory of the forms of social justice will be addressed in this policy.For example,equity,redistribution,recognition,capabilities.After that,the challenges and struggles of the policy implementation will be indicated.Connecting with the practitioner's current situation and concentrates on the relevant skills that will be improved,applied as a practitioner for professional development and the way to cooperate with children’s parents in the context of early years setting.That is why this policy was chosen by the author.Finally,a conclusion with the critical points of the significance of parental involvement during the process of closing the attainment gap will be offered. 展开更多
关键词 attainment gap Parental engagement EQUITY Policy Social commitment
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The effects of Age of Acquisition on an L2 learner’s Ultimate Attainment
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作者 Xinlu Li 《Journal of Contemporary Educational Research》 2020年第5期23-26,共4页
This paper focuses on generalizing different theories towards the age effect on the ultimate attainment of second language learners since it has long been a controversial topic in researchers’mind.In this paper,it gi... This paper focuses on generalizing different theories towards the age effect on the ultimate attainment of second language learners since it has long been a controversial topic in researchers’mind.In this paper,it gives evidences on cases in favor of the Critical Period Hypothesis,which claimed the loss of language learning ability after puberty and presents counter-evidences on the successful acquisition of second language in adult learners.It has reached into a conclusion that consists the viewpoint drawn on previous analysis and confirmed the possibility in ultimate second language attainment for late learners. 展开更多
关键词 Ultimate attainment Critical Period Second Language Acquisition
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Design and demonstration of a next-generation air quality attainment assessment system for PM_(2.5)and O_3 被引量:11
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作者 Hua Wang Yun Zhu +9 位作者 Carey Jang Che-Jen Lin Shuxiao Wang Joshua S.Fu Jian Gao Shuang Deng Junping Xie Dian Ding Xuezhen Qiu Shicheng Long 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第3期178-188,共11页
Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Comm... Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy. 展开更多
关键词 Air quality standards attainment test Air pollution GIS Emission control
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A case study of development and application of a streamlined control and response modeling system for PM_(2.5)attainment assessment in China 被引量:9
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作者 Shicheng Long Yun Zhu +7 位作者 Carey Jang Che-Jen Lin Shuxiao Wang Bin Zhao Jian Gao Shuang Deng Junping Xie Xuezhen Qiu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第3期69-80,共12页
This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streaml... This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_(2.5) attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_(2.5) to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition(SMAT-CE),and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta(YRD) in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality(CMAQ) model simulation results with maximum mean normalized error 〈 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_(2.5) in January and August(e.g.,more than50%contributed by primary emissions in Shanghai),and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China's annual PM_(2.5)National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_(2.5)(and potentially O_3 as well) and streamline air quality data for SMAT-CE to perform attainment assessments. 展开更多
关键词 Response surface model RSM-Linear coupled fitting Air quality modeling attainment assessment PM_(2.5)
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Effect of birth month on educational attainment and adult cognition in Rural China 被引量:1
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作者 Lijun Chen Qiang Ren 《China Population and Development Studies》 2022年第2期163-185,共23页
The association of season of birth with cognitive development,academic perfor-mance and educational attainment has been well documented in western countries.However,little research has been conducted in developing cou... The association of season of birth with cognitive development,academic perfor-mance and educational attainment has been well documented in western countries.However,little research has been conducted in developing countries to examine the seasonality of cognitive achievement.In this study,we analyzed data of a nationally representative sample of over 8500 rural adults born in the 1960s and early 1970s from the 2010 China Family Panel Studies survey.The results of logistic regression models demonstrate a significant association of birth month with educational attain-ment even with relevant individual and parental information controlled.Specially,we found that rural respondents born in the months of March and April are much less likely to obtain a high school degree than those born late in the year from Octo-ber to December.The seasonal pattern is also found to significantly affect current cognitive achievements of the respondents even after their educational attainment and family social economic conditions are taken into account.Finally,we discussed the merits of age position theory and fetal origin interpretation as potential mecha-nisms for the seasonal pattern of education attainment,and suggest that seasonal changes of nutritional intake for pregnant mothers are the most likely cause. 展开更多
关键词 Educational attainment Birth month Cognitive achievement Fetal origin
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The Use of Goal Attainment Scaling in the Acupuncture of Children with Intellectual Disability
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作者 Si-Jia Zhang Dong Lin +4 位作者 Li-Li Lin Shi-Yi Qi Meng Gong Shi-Bin Li Jie Zhang 《World Journal of Traditional Chinese Medicine》 CAS 2022年第4期522-529,共8页
Objective: The therapeutic effect of acupuncture is often evaluated based on the experience and judgment of acupuncturists and the subjective feelings of patients. Thus, we investigated the suitability of goal attainm... Objective: The therapeutic effect of acupuncture is often evaluated based on the experience and judgment of acupuncturists and the subjective feelings of patients. Thus, we investigated the suitability of goal attainment scaling(GAS), an objective outcome measurements, to evaluate the responsiveness of children with intellectual disability to acupuncture therapy. Methods: This is an assessor-blinded, single-group cohort study that included 17 children with intellectual disabilities. The therapeutic effect of acupuncture was assessed by the T scores of GAS at four time points during the 3-month treatment. The responsiveness of GAS to acupuncture therapy was measured using the standardized response mean(SRM). Results: Compared with control, the 4-, 8-, and 12-week scores improved significantly after treatment(P < 0.01, P≤0.001,P≤0.001), with significant differences between each month(P < 0.01, P≤0.001, P≤0.001). Furthermore, all periods assessed GAS(to measure the therapeutic effect of acupuncture) showed marked responsiveness(SRMs >0.8). Conclusion: GAS is responsive in evaluating individual changes in the acupuncture treatment of children with intellectual disabilities. It is a feasible tool to match both the needs of children with intellectual disabilities and the clinical characteristics of acupuncture. 展开更多
关键词 ACUPUNCTURE goal attainment scaling intellectual disability
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The Effect of Sibling Size on Children’s Educational Attainment:Evidence From Indonesia
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作者 冯乃康 《ECNU Review of Education》 2021年第4期830-856,共27页
Purpose:This study examines the effect of sibling size on children’s educational attainment in Indonesia.Design/Approach/Methods:To establish causality,it exploits the exogenous variation of sibling size caused by tw... Purpose:This study examines the effect of sibling size on children’s educational attainment in Indonesia.Design/Approach/Methods:To establish causality,it exploits the exogenous variation of sibling size caused by twin birth in families.Findings:Results of instrumental variable(IV)estimation support a traditional wisdom of quantity-quality trade-off,where sibling size is negatively correlated with the completed years of schooling,educational levels,and likelihood of school attendance.Building on this,the subsample analysis reveals that the negative effect is larger for Muslim children,children with less educated mothers,and children belonging to earlier birth cohorts.Originality/Value:These findings provide insights into both population and education policymaking in developing countries. 展开更多
关键词 Educational attainment family planning Indonesia sibling size
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Development of educational attainment and gender equality in China:new evidence from the 7th National Census
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作者 Haidong Xu Hao Zhou Yuqian Xu 《China Population and Development Studies》 2022年第4期425-451,共27页
This paper discusses the status and changes in educational attainment and gender inequality in education for the Chinese population based on the data from the 7th National Census of China and previous censuses since 1... This paper discusses the status and changes in educational attainment and gender inequality in education for the Chinese population based on the data from the 7th National Census of China and previous censuses since 1982.The results indicate that gender inequality in education has lessened while educational attainment has improved.However,it is necessary to continue to eradicate illiteracy in the West,further promote compulsory education rates,increase the advancement rate to high school,and reduce the urban-rural gap in education to further develop education.This paper indicates that the increased educational opportunities for women combined with their relatively superior academic abilities have resulted in a new reversed gender inequality in that males are at a disadvantage,especially in higher education.The fact that women have benefited more from the expansion of higher education than men have was an unintended consequence of China's one-child fertility policy since the family resources are less diluted by fewer children in a household and daughters are regarded as long-term family members.This paper further reveals that although women outperform men at every level of the educational system,they often voluntarily withdraw from pursuing doctoral degrees due to the increasing pressure as they age and age discrimination which drives them to enter marriage and the labor market earlier than men do. 展开更多
关键词 Educational attainment China Educational structure Gender inequality in education
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An Analysis of the Relationship Between the Education Attainment and Economic Status of the Elderly Population in the Towns and Cities of China
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作者 Sha Jicai Sha Jicai works in the Institute of Population Research,China Academy of Social Science 《China City Planning Review》 1990年第4期52-59,共8页
Viewed from a macro scope,the cultureof a community is closely related to its econ-omy.Economy being the basis,the level ofeconomic growth determines the level ofcultural development.Conversely,culturecan act as the p... Viewed from a macro scope,the cultureof a community is closely related to its econ-omy.Economy being the basis,the level ofeconomic growth determines the level ofcultural development.Conversely,culturecan act as the precursor and cultural devel-opment enhances economic growth.Likewise,the education attainment of an in-dividual reflects the same sort 展开更多
关键词 rate more An Analysis of the Relationship Between the Education attainment and Economic Status of the Elderly Population in the Towns and Cities of China
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A New Era: New Orientation for Development, and New Goals for Attainment
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作者 Chen Shuguang 《Peace》 2018年第1期7-11,共5页
A new era of socialism with Chinese characteristics is the era of inheriting the past and carrying forward into the future, and continuously winning the great victory of socialism with Chinese characteristics under th... A new era of socialism with Chinese characteristics is the era of inheriting the past and carrying forward into the future, and continuously winning the great victory of socialism with Chinese characteristics under the new historical conditions; is the era of making a decisive victory in building a moderately prosperous society in all-respects and building a socialist modern country in an all-round way; is the era for the people of all ethnic groups to unite and strive to continuously create a better life and to gradually realize the common prosperity of all the people; is the era to realize the Chinese dream featuring all the Chinese people making concerted efforts and striving to achieve the great rejuvenation of the Chinese nation; is an era in which China is increasingly approaching the center of the world stage and continuously making greater contributions to human kind. 展开更多
关键词 A New Era New Orientation for Development and New Goals for attainment
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Low-density lipoprotein cholesterol target goal attainment rate and related factors in patients with acute coronary syndrome after percutaneous coronary intervention
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作者 张波 《China Medical Abstracts(Internal Medicine)》 2014年第2期93-93,共1页
Objective To observe the low-density lipoprotein cholesterol(LDL-C)target goal attainment rate and related factors in patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods Fro... Objective To observe the low-density lipoprotein cholesterol(LDL-C)target goal attainment rate and related factors in patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods From March 2011 to March 2012,a total of832 ACS patients were retrospectively evaluated in the Cardiology Department of the First Affiliated Hospital of Dalian Medical University.The target goal 展开更多
关键词 CHOLESTEROL DALIAN prior goals PENDENT prevention attain recommended ESC BASELINE
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基于集成高效热能发电系统的船舶Attained EEDI及燃油消耗量分析 被引量:9
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作者 袁成清 潘鹏程 +3 位作者 孙玉伟 严新平 张彦 汤旭晶 《中国造船》 EI CSCD 北大核心 2018年第1期197-206,共10页
为满足国际海事组织(IMO)关于船舶能效设计指数(energy efficiency design index,EEDI)的强制要求,各国已开始探索高效热能发电技术在船舶能源系统中的集成和应用,以期通过对船舶主动力装置余热进行回收利用,实现降低EEDI、减少燃油消... 为满足国际海事组织(IMO)关于船舶能效设计指数(energy efficiency design index,EEDI)的强制要求,各国已开始探索高效热能发电技术在船舶能源系统中的集成和应用,以期通过对船舶主动力装置余热进行回收利用,实现降低EEDI、减少燃油消耗量和控制废气排放量的目标。论文以超临界二氧化碳布雷顿循环(S-CO_2 Brayton cycle,S-CO_2 BC)发电系统、有机朗肯循环(organic Rankine cycle,ORC)余热发电系统、卡琳娜循环(Kalina cycle,KC)余热发电系统和动力涡轮(power turbine,PT)余热发电系统为具体研究对象,分别就单一新型动力循环发电系统和组合型高效热能发电系统在某型2500TEU支线集装箱船中集成,对船舶达到的能效设计指数(attained EEDI)和燃油消耗量折减进行计算分析。结果表明:采用超临界二氧化碳布雷顿循环发电系统取代1台船舶辅机,并与有机朗肯循环、卡琳娜循环及动力涡轮等新型动力循环余热发电系统构成组合型高效热能余热发电系统技术方案,可实现船舶达到的能效设计指数EA与没有应用任何高效热能发电系统技术方案的指数相比下降33.28%;单一应用有机朗肯循环余热发电技术对减少船舶燃油消耗量的贡献显著,燃油节省率可达到5.99%。这项研究工作可为在船舶上集成应用高效热能发电技术提供理论参考依据。 展开更多
关键词 船舶余热利用 高效热能发电 达到的能效设计指数(attained EEDI) 燃油消耗量
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用Authorware 5 Attain制作二阶液位——流量系统CAI课件
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作者 袁浩 孟祥义 《实验室科学》 2005年第6期48-50,共3页
本文介绍了用Macromedia公司最新推出的多媒体制作软件-Authorware5 Attain制作采用Honeywell UDC3300数字调节器的新型二阶液位-流量综合实验系统的CAI课件.
关键词 AUTHORWARE5 Attain CAI课件 液位-流量
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Computer Assisted Learning for Improving Cattle Palpation Skills of Veterinary Students
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作者 Scott T. Norman Gloria Dall’Alba 《Open Journal of Veterinary Medicine》 2013年第8期319-327,共9页
This study investigated the effect of a computer assisted learning (CAL) tool on the development of skills in palpation of the reproductive tract of the cow per rectum (rectal palpation) by fourth-year students in a B... This study investigated the effect of a computer assisted learning (CAL) tool on the development of skills in palpation of the reproductive tract of the cow per rectum (rectal palpation) by fourth-year students in a Bachelor of Veterinary Science (BVSc) degree program. A secondary aim was to determine if animal welfare could be improved by the CAL intervention. The CAL tool was developed to provide: vivid, three-dimensional interactive graphics of the relevant anatomy and skills;a comprehensive glossary of terminology used in association with the skills;and formative assessment tasks. Prior to its introduction to the course, industry stakeholders assessed the CAL tool graphics as an accurate depiction of the procedures. Two consecutive cohorts of students were surveyed prior to (n = 91) and after the CAL intervention (n = 111). Responses to student surveys suggested that post-intervention skills were learned at approximately the same rate as pre-intervention. However, tutor surveys indicated that students in the pre-intervention group may have had insufficient understanding for accurate self-assessment compared to post-intervention students. According to tutors, substantially more students in the post-intervention group gained practical skills at an improved rate and to a higher level of competency. Both student and tutor surveys indicated that there was a minimal discomfort to animals in these practical classes. From an animal welfare point-of-view, it was concluded that the intervention would not result in a reduction in the number of animals required during practical sessions. However, due to the preparation and reinforcement provided by the CAL tool, animals were used more efficiently by students after the intervention, resulting in the attainment of a higher level of skill. Knowledge gained from this study may be relevant to other disciplines requiring students to develop practical skills associated with animals or humans. 展开更多
关键词 COMPUTER Assisted Learning (CAL) COMPUTER Simulation VETERINARY Science EDUCATION SKILL attainment Professional EDUCATION
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Association between Teacher Candidates'Competency and First-Year Employment in Physical Education:A Comparison Study
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作者 YuChun Chen Brian Myers 《Journal of International Education and Practice》 2021年第3期14-21,共8页
Physical education teacher education(PETE)programs prepare teacher candidates to be competent and employed in P-12 school settings.This study examined the relationship between competency and first-year job obtainment ... Physical education teacher education(PETE)programs prepare teacher candidates to be competent and employed in P-12 school settings.This study examined the relationship between competency and first-year job obtainment in physical education(PE).Participants included 111 teacher candidates from two schools.Participants'competency in content knowledge in Kinesiology and sub-disciplines(CKKH),content knowledge in sport and skill proficiency(CKSP),pedagogical content knowledge(PCK),and first-year job obtainment in PE were collected.Descriptive statistics,independent-samples t tests,and multiple logistic regressions were used to analyze the data.The overall sample showed participants were most competent in PCK,followed by CKSP and CKKH.Female participants were more competent in PCK than their male counterparts,and those at School A performed better in CKSP and PCK than their peers at School B.As a sample,more than half of the participants(55.9%)obtained PE jobs.There was a significance between the overall sample and female participants'competency in CKKH and their first-year employment in PE.This study was limited by sample size,variances in courses between the two schools,and by the defined timeline to clarify first-year PE employment.Implications regarding the importance of CKKH and first-year employment were discussed. 展开更多
关键词 Teacher education Physical education teacher education Content knowledge Pedagogical content knowledge COMPETENCE Job attainment
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Regional distribution of wheat yield and chemical fertilizer requirements in China 被引量:5
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作者 XU Xin-peng HE Ping +7 位作者 CHUAN Li-min LIU Xiao-yan LIU Ying-xia ZHANG Jia-jia HUANG Xiao-meng QIU Shao-jun ZHAO Shi-cheng ZHOU Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第10期2772-2780,共9页
Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a ... Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a total of 5408 field experiments were collected from 2000 to 2015 across the major wheat production regions in China to analyze the spatial distribution of wheat yield,the soil nutrient supply capacity(represented by relative yield,defined as the ratio of the yield under the omission of one of nitrogen(N),phosphorus(P)and potassium(K)to the yield under the full NPK fertilizer application),and N,P and K fertilizer requirements by combining the kriging interpolation method with the Nutrient Expert Decision Support System for Wheat.The results indicated that the average attainable yield was 6.4 t ha^(−1),with a coefficient of variation(CV)of 24.9% across all sites.The yields in North-central China(NCC)and the northern part of the Middle and Lower reaches of the Yangtze River(MLYR)were generally higher than 7 t ha^(−1),whereas the yields in Southwest China(SWC),Northeast China(NEC),and the eastern part of Northwest China(NWC)were usually less than 6 t ha^(−1).The precentage of area having a relative yield above 0.70,0.85,and 0.85 for N,P,and K fertilizers accounted for 52.3,74.7,and 95.9%,respectively.Variation existed in N,P,and K fertilizer requirements,with a CV of 24.8,23.9,and 29.9%,respectively,across all sites.More fertilizer was needed in NCC and the northern part of the MLYR than in other regions.The average fertilizer requirement was 162,72,and 57 kg ha^(−1) for N,P2O5,and K2O fertilizers,respectively,across all sites.The incorporation of the spatial variation of attainable yield and fertilizer requirements into wheat production practices would benefit sustainable wheat production and environmental safety. 展开更多
关键词 WHEAT attainable yield fertilizer requirements nutrient expert system spatial variation
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Prompt efficiency of energy harvesting by magnetic coupling of an improved bi-stable system 被引量:1
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作者 李海涛 秦卫阳 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第11期174-183,共10页
In order to improve the transform efficiency of bi-stable energy harvester(BEH),this paper proposes an advanced bi-stable energy harvester(ABEH),which is composed of two bi-stable beams coupling through their magn... In order to improve the transform efficiency of bi-stable energy harvester(BEH),this paper proposes an advanced bi-stable energy harvester(ABEH),which is composed of two bi-stable beams coupling through their magnets.Theoretical analyzes and simulations for the ABEH are carried out.First,the mathematical model is established and its dynamical equations are derived.The formulas of magnetic force in two directions are given.The potential energy barrier of ABEH is reduced and the snap-through is liable to occur between potential wells.To demonstrate the ABEH's advantage in harvesting energy,comparisons between the ABEH and the BEH are carried out for both harmonic and stochastic excitations.Our results reveal that the ABEH's inter-well response can be elicited by a low-frequency excitation and the harvester can attain frequent jumping between potential wells at fairly weak random excitations.Thus,it can generate a higher output power.The present findings prove that the ABEH is preferable in harvesting energy and can be optimally designed such that it attains the best harvesting performance. 展开更多
关键词 harvesting piezoelectric attain directions liable stochastic fairly clamped dynamical harmonic
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