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Feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia
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作者 Michael S.Lukubwe Daniel Velarde-Garcéz +3 位作者 Fernando Sequeira Susana Lopes Adrian J.F.K.Craig Vanessa A.Mata 《Avian Research》 SCIE CSCD 2024年第3期336-344,共9页
As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic relationships.Due to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the... As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic relationships.Due to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be variable.In addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the host.Here,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(B.erythrorhynchus)in northeastern Namibia.In contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same samples.With this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod species.Our findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an individual.We observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal host.We noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal hosts.This study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission. 展开更多
关键词 COMMENSALISM Diet DNA metabarcoding Oxpeckers PARASITISM Trophic ecology
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A Stacking Machine Learning Model for Student Performance Prediction Based on Class Activities in E-Learning
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作者 Mohammad Javad Shayegan Rosa Akhtari 《Computer Systems Science & Engineering》 2024年第5期1251-1272,共22页
After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation ... After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation of vast amounts of valuable data,making it an attractive resource for predicting student performance.In this study,we aimed to predict student performance based on the analysis of data collected from the OULAD and Deeds datasets.The stacking method was employed for modeling in this research.The proposed model utilized weak learners,including nearest neighbor,decision tree,random forest,enhanced gradient,simple Bayes,and logistic regression algorithms.After a trial-and-error process,the logistic regression algorithm was selected as the final learner for the proposed model.The results of experiments with the above algorithms are reported separately for the pass and fail classes.The findings indicate that the accuracy of the proposed model on the OULAD dataset reached 98%.Overall,the proposed method improved accuracy by 4%on the OULAD dataset. 展开更多
关键词 STACKING e-learning student performance prediction machine learning CLASSIFICATION
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A bibliometric analysis using machine learning to track paradigm shifts and analytical advances in forest ecology and forestry journal publications from 2010 to 2022
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作者 Jin Zhao Liyu Li +4 位作者 Jian Liu Yimei Yan Qian Wang Chris Newman Youbing Zhou 《Forest Ecosystems》 SCIE CSCD 2024年第5期770-779,共10页
Forest habitats are critical for biodiversity,ecosystem services,human livelihoods,and well-being.Capacity to conduct theoretical and applied forest ecology research addressing direct(e.g.,deforestation)and indirect(e... Forest habitats are critical for biodiversity,ecosystem services,human livelihoods,and well-being.Capacity to conduct theoretical and applied forest ecology research addressing direct(e.g.,deforestation)and indirect(e.g.,climate change)anthropogenic pressures has benefited considerably from new field-and statistical-techniques.We used machine learning and bibliometric structural topic modelling to identify 20 latent topics comprising four principal fields from a corpus of 16,952 forest ecology/forestry articles published in eight ecology and five forestry journals between 2010 and 2022.Articles published per year increased from 820 in 2010 to 2,354 in 2021,shifting toward more applied topics.Publications from China and some countries in North America and Europe dominated,with relatively fewer articles from some countries in West and Central Africa and West Asia,despite globally important forest resources.Most study sites were in some countries in North America,Central Asia,and South America,and Australia.Articles utilizing R statistical software predominated,increasing from 29.5%in 2010 to 71.4%in 2022.The most frequently used packages included lme4,vegan,nlme,MuMIn,ggplot2,car,MASS,mgcv,multcomp and raster.R was more often used in forest ecology than applied forestry articles.R software offers advantages in script and workflow-sharing compared to other statistical packages.Our findings demonstrate that the disciplines of forest ecology/forestry are expanding both in number and scope,aided by more sophisticated statistical tools,to tackle the challenges of redressing forest habitat loss and the socio-economic impacts of deforestation. 展开更多
关键词 Forest ecology FORESTRY R software Structural topic modelling Machine learning PUBLICATION
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Efficient Intelligent E-Learning Behavior-Based Analytics of Student’s Performance Using Deep Forest Model
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作者 Raed Alotaibi Omar Reyad Mohamed Esmail Karar 《Computer Systems Science & Engineering》 2024年第5期1133-1147,共15页
E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analyt... E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analytics systemto support academic evaluation for students via e-learning activities to overcome the challenges faced by traditional learning environments.The proposed e-learning analytics system includes a new deep forest model.It consists of multistage cascade random forests with minimal hyperparameters compared to traditional deep neural networks.The developed forest model can analyze each student’s activities during the use of an e-learning platform to give accurate expectations of the student’s performance before ending the semester and/or the final exam.Experiments have been conducted on the Open University Learning Analytics Dataset(OULAD)of 32,593 students.Our proposed deep model showed a competitive accuracy score of 98.0%compared to artificial intelligence-based models,such as ConvolutionalNeuralNetwork(CNN)and Long Short-TermMemory(LSTM)in previous studies.That allows academic advisors to support expected failed students significantly and improve their academic level at the right time.Consequently,the proposed analytics system can enhance the quality of educational services for students in an innovative e-learning framework. 展开更多
关键词 e-learning behavior data student evaluation artificial intelligence machine learning
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Landscape Architecture Planning and Design Based on Landscape Ecology Theory:A Case Study of Waterfront Landscape Planning and Design of Dapo Town
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作者 WANG Sangju XIAO Shizhen 《Journal of Landscape Research》 2024年第1期35-39,42,共6页
With the rapid development of urbanization,landscape architecture has become an indispensable component of daily life.In order to achieve better landscape effects and protect the ecological environment,landscape ecolo... With the rapid development of urbanization,landscape architecture has become an indispensable component of daily life.In order to achieve better landscape effects and protect the ecological environment,landscape ecology theory can be integrated into landscape planning to carry out disciplinary crossing and integration research between landscape ecology and landscape architecture.In this study,based on the basic theories of landscape ecology,the waterfront landscape of Dapo Town was designed,with the aim to achieve ecological balance in planning,showcase biodiversity,and create a harmonious landscape ecological environment which can benefit both nature and people.This design combined artificial and natural elements while improving the natural environment,which promoted a harmonious relationship between humans and nature,thus enriching the spatial organization of the city,and playing a role in regulating the urban environment and climate. 展开更多
关键词 Landscape ecology theory Landscape architecture planning and design Dapo Town Waterfront landscape
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Study on the Aesthetic Deformation of Micro Short Drama Audience from the Perspective of Media Ecology
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作者 LI Ming-xia LI Jia-xin 《Journal of Literature and Art Studies》 2024年第10期908-915,共8页
Micro short drama is a new form of fictional narrative in the environment of digital intelligent media,which attracts the attention of the audience in the era of fragmentation and forms an explosive growth of the indu... Micro short drama is a new form of fictional narrative in the environment of digital intelligent media,which attracts the attention of the audience in the era of fragmentation and forms an explosive growth of the industrial market with the characteristics of short content,concentrated dramatic conflict and quick plot reversal.However,the“viral”dissemination of micro short drama makes the audience’s aesthetics show the aesthetic deformation characteristics of earthy,ugly and non-reality.The article applies media ecology Neil Postman’s theories of“entertainment to death”and“technological monopoly”to observe the impact of micro short dramas on audience aesthetics in order to optimize the market of micro short dramas and guide the healthy development of audience aesthetics. 展开更多
关键词 micro short drama media ecology aesthetic deformation
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Floristic and Structural Analysis of Urban Tree Canopy: From Its Ecology to Its Social Issues
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作者 Richieri Antonio Sartori Ana Paula Balderi +3 位作者 Camila Conti Anna Thereza Carcamo Henrique Rajão Jakeline Prata de Assis Pires 《Journal of Geoscience and Environment Protection》 2024年第11期1-28,共28页
Currently, urban areas are the largest segment of the world’s population, and they can reach up to 80% of it in some countries. Understanding green areas is of paramount importance to also understand the population’... Currently, urban areas are the largest segment of the world’s population, and they can reach up to 80% of it in some countries. Understanding green areas is of paramount importance to also understand the population’s mental health and well-being, as well as to achieve ecological understanding and its impact on urban infrastructure. Thus, the aim of the present study is to carry out a survey on both urban afforestation structure and on its social impact on a Brazilian municipality. It also sought to understand the damages caused by these species to urban infrastructure in comparison to data collected in 2009, to assess forest coverage in this municipality and tree planting underutilized capacity. Accordingly, all the streets in this municipality’s urban area, the botanical data of each tree and its damage to the city’s infrastructure and phytosanitary conditions were surveyed (from 1 to 5). Data were compared to those from the 2009 census, and social issues were analyzed. In total, 5044 individuals belonging to 189 species were recorded. The most often found species were Lagerstroemia indica and Murraya paniculata. Out of the total number of trees, 458 trees scored at least one score “5” in one of the criteria, and this number represents 8.9% of the total of the trees. L. indica was the species accounting for the highest rates of phytosanitary and infrastructure issues. Data comparison evidenced that urban tree canopy lost 25% of its vegetation between the two measurements taken herein, but the number of species has increased. When it comes to damages, many trees started showing phytosanitary issues or damage to urban infrastructure. 展开更多
关键词 Urban ecology Urban Tree Canopy Impact on Urban Infrastructure Socorro-SP Green Coverage
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Ecology
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作者 《疯狂英语(初中天地)》 2024年第10期52-54,共3页
What is it?Ecology is the science of how humans,animals and plants live together.For example,in the city you can find birds,rats,insects and plants that all live in the same space.Many of them eat things that people ... What is it?Ecology is the science of how humans,animals and plants live together.For example,in the city you can find birds,rats,insects and plants that all live in the same space.Many of them eat things that people don’t want any more.If you go to a forest,you can see different kinds of plants,insects,small animals like rabbits and birds living there;they all eat different things in the forest,and some eat each other! 展开更多
关键词 FOREST space. ecology
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Discussion on Influencing Factors of Water Resources Environment and Strategies for Protecting Water Ecology
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作者 Wangzi Zhou Jing Dong +1 位作者 Qianyi Zhao Qianxun Li 《Journal of World Architecture》 2024年第5期36-41,共6页
At present,the major problems facing the water resource environment worldwide include water pollution,water resource shortage,and water ecosystem degradation.The discharge of industrial wastewater,agricultural non-poi... At present,the major problems facing the water resource environment worldwide include water pollution,water resource shortage,and water ecosystem degradation.The discharge of industrial wastewater,agricultural non-point source pollution,and the discharge of urban sewage lead to a serious decline in water quality,which directly affects the safety of human drinking water and the living environment of aquatic organisms.Additionally,the unbalanced distribution and excessive exploitation of water resources lead to the problem of water shortage in many areas,which then leads to social and economic contradictions and ecological crises.In terms of ecosystems,the phenomena of water ecological degradation and reduction of biodiversity are increasingly obvious,and the carrying capacity of aquatic ecosystems are gradually declining.This paper aims to analyze the natural,social,and economic factors affecting the water resource environment,and propose effective strategies to protect the water ecology.To provide a theoretical basis and practical guidance for the sustainable utilization of water resources and the long-term development of the water ecosystem. 展开更多
关键词 Water resources Environmental impact Water ecology Protection strategy
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基于E-learning的混合式教学模式研究 被引量:46
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作者 魏绍蓉 王晓英 +1 位作者 刘志强 樊丽华 《实验技术与管理》 CAS 北大核心 2014年第12期20-22,共3页
在通过对当前教育环境的发展变化和E-Learning的发展与创新进行研究分析的基础上,对ELearning与传统教学模式进行比较,提出将基于先进的网络技术的E-learning教学模式与传统的教学模式有机地结合,互相补充,最大限度地体现各自教学模式... 在通过对当前教育环境的发展变化和E-Learning的发展与创新进行研究分析的基础上,对ELearning与传统教学模式进行比较,提出将基于先进的网络技术的E-learning教学模式与传统的教学模式有机地结合,互相补充,最大限度地体现各自教学模式的精华,强烈地激发学生主动学习的潜力,最终形成基于E-Learning的混合式教学模式。这是一种开放性、创新性的教育思想和模式,从而有效突破了传统校园教育的局限,提高了教学资源利用率,并促进了教学质量的提升,同时也增进了各高校之间的教学联系和学术交流,带来了更多的知识创新成果,最终提高了教育质量。 展开更多
关键词 e-learning 教育环境 教学模式
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E-learning 3.0:内涵、挑战与生态框架 被引量:5
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作者 上超望 尹爱青 +2 位作者 吴圆圆 段智辰 周孟 《现代教育技术》 CSSCI 2016年第12期18-23,共6页
E-learning 3.0实现了随时随地的连接和学习,为学习与教育带来了新的机遇与挑战。文章通过E-learning 3.0的历史变迁和E-learning 3.0与Web 3.0的关系,对E-learning 3.0的内涵进行了界定,探讨了E-learning 3.0面临的挑战,并提出了一种... E-learning 3.0实现了随时随地的连接和学习,为学习与教育带来了新的机遇与挑战。文章通过E-learning 3.0的历史变迁和E-learning 3.0与Web 3.0的关系,对E-learning 3.0的内涵进行了界定,探讨了E-learning 3.0面临的挑战,并提出了一种基于可持续发展理念的E-learning 3.0的生态框架,分析了其生态框架中各要素的功能与层级关系,旨在为数字教育的协调发展与创新提供有益的借鉴。 展开更多
关键词 e-learning 3.0 内涵 生态框架 协调发展
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企业E-learning现状调查与分析——以TCL集团为研究个案 被引量:14
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作者 丁新 龚静红 陈立勇 《开放教育研究》 CSSCI 2008年第2期100-104,共5页
借助互联网的应用热潮,E-learning这一数字化学习方式已经成为各大企业开展员工培训的重要方式。TCL集团作为我国"数字化学习港"教学改革项目唯一的企业示范点,正努力探索"数字化学习型企业"的建设及运行规律;而企... 借助互联网的应用热潮,E-learning这一数字化学习方式已经成为各大企业开展员工培训的重要方式。TCL集团作为我国"数字化学习港"教学改革项目唯一的企业示范点,正努力探索"数字化学习型企业"的建设及运行规律;而企业管理者和员工对E-learning的认识、需求及习惯是创建"数字化学习型企业"的重要依据。本文以TCL集团为个案,通过对其下属公司管理者和员工的问卷调查、访谈与分析,发现企业培训主管和企业员工都对采用E-learning培训有强烈愿望并持肯定态度,但对E-learning的认识尚不够深入;同时企业在E-learning的组织实施及提供学习支持服务等方面仍需进一步探索。 展开更多
关键词 企业 e-learning 调查 分析
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本体驱动的e-Learning知识资源个性化推荐研究 被引量:20
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作者 赵蔚 姜强 +1 位作者 王朋娇 王丽萍 《中国电化教育》 CSSCI 北大核心 2015年第5期84-89,共6页
e-Learning重要特点就是能够根据学习者特性、需求,适应性呈现学习资源和学习路径,实现个性化学习,有效促进学习目标达成。为实现e-Learning知识资源个性化推荐,该文采用基于知识推荐技术,同时基于本体技术创建学习者知识和知识资源,在... e-Learning重要特点就是能够根据学习者特性、需求,适应性呈现学习资源和学习路径,实现个性化学习,有效促进学习目标达成。为实现e-Learning知识资源个性化推荐,该文采用基于知识推荐技术,同时基于本体技术创建学习者知识和知识资源,在教学模式的指导下实现知识资源个性化推荐。实验结果表明:学生能够很好理解本体概念,愿意学习本体知识,同时认为本体驱动的知识资源个性化推荐很有用,能够满足个性化学习需求、激发学习者学习动机、增强网络自主学习能力及优化学习过程。本文研究的意义:一是基于学习者特征讨论了合适的推荐技术;二是设计了学习者知识和学习资源的通用本体;三是为知识资源个性化推荐设计了有效指导教学模式。 展开更多
关键词 本体 个性化 e-learning 基于知识推荐 知识资源
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E-learning网络平台的构建及应用效果分析 被引量:19
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作者 黄华兴 袁艺标 +6 位作者 刘力嘉 杨海源 沈历宗 夏添松 秦超 叶俊 王水 《实验室研究与探索》 CAS 北大核心 2017年第2期200-203,共4页
目的:传统课程以面对面授课为主,不能满足现代教学发展的需要。Elearning是在线学习新方式,通过计算机互联网或手机无线网络进行网络授课、答疑和论坛交流。方法:通过E-learning网络平台的构建及应用,对比分析网络平台应用前后学生掌握... 目的:传统课程以面对面授课为主,不能满足现代教学发展的需要。Elearning是在线学习新方式,通过计算机互联网或手机无线网络进行网络授课、答疑和论坛交流。方法:通过E-learning网络平台的构建及应用,对比分析网络平台应用前后学生掌握知识的程度和师生交流的密切程度,实验组与对照组医学生的实验考核、理论考试成绩输入Excel 2007,并用Stata 19.0统计分析。结果:常规课堂教学以外开发E-learning平台并强化利用,确能提高学生成绩,促进师生互动,不失为传统授课方式的有益补充。结论:课堂教学为主,E-learning学习为辅的教学模式符合当前信息社会的发展趋势和学生的学习规律,相辅相成,共同促进医学生知识的掌握和临床技能水平的提高。但E-learning平台建设是一项系统工程,必须长远规划,循序渐进,逐步完善,方能发挥更大效能。 展开更多
关键词 外科学基础 e-learning平台 医学院 教学模式
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基于情境感知和本体的E-Learning系统研究 被引量:15
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作者 赵海燕 詹永照 王传安 《计算机工程与应用》 CSCD 2012年第16期51-56,共6页
为了合理、有效地描述E-Learning环境中学习者的学习情形,利用本体论具有知识组织清晰、概念和关系定义明确的特性,建立了E-Learning环境中的情境信息本体模型。为提高学习者的学习兴趣和学习效率,对采集到的情境信息进行情境推理后,采... 为了合理、有效地描述E-Learning环境中学习者的学习情形,利用本体论具有知识组织清晰、概念和关系定义明确的特性,建立了E-Learning环境中的情境信息本体模型。为提高学习者的学习兴趣和学习效率,对采集到的情境信息进行情境推理后,采用资源调度控制算法调用相应的学习资源服务及时向学习者提供。应用实例验证了基于情境感知的本体E-Learning系统的服务性能。 展开更多
关键词 情境感知 e-learning 本体 情境信息
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通过《Landscape Ecology》杂志看国际景观生态学研究动向 被引量:10
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作者 冷文芳 肖笃宁 +2 位作者 李月辉 胡远满 贺红士 《生态学杂志》 CAS CSCD 北大核心 2004年第5期140-144,共5页
《LandscapeEcology》是刊载景观生态学文章的重要期刊。本文以该期刊为研究对象 ,总结自 1987年创刊以来所刊载的 5 72篇文章的关键词所体现出的景观生态学的学科体系 (理论 -原理、研究方法、实际应用 )、研究内容 (景观格局、景观过... 《LandscapeEcology》是刊载景观生态学文章的重要期刊。本文以该期刊为研究对象 ,总结自 1987年创刊以来所刊载的 5 72篇文章的关键词所体现出的景观生态学的学科体系 (理论 -原理、研究方法、实际应用 )、研究内容 (景观格局、景观过程、景观变化 )和研究对象 (景观类型、景观要素 )的发展历程 ,并对这些关键词进行时段归类和统计分析 ,提炼出各时段的研究热点并分析未来景观生态学热点发展方向。 展开更多
关键词 《Landscape ecology》杂志 关键词统计 景观原理 研究方法 实际应用 格局 过程 变化 景观类型 景观要素
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面向e-Learning的概念知识元表征模型研究 被引量:15
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作者 吴林静 刘清堂 +2 位作者 黄景修 刘? 毛刚 《电化教育研究》 CSSCI 北大核心 2015年第4期44-49,共6页
知识表征是个性化学习系统的基础。由于知识本身具有多粒度、多维度的特征,而且知识点与知识点之间存在着复杂的语义联系,因此通用的"资源—索引—元数据"的三级资源组织模式不能很好地满足学习者知识学习的需要。针对这一现... 知识表征是个性化学习系统的基础。由于知识本身具有多粒度、多维度的特征,而且知识点与知识点之间存在着复杂的语义联系,因此通用的"资源—索引—元数据"的三级资源组织模式不能很好地满足学习者知识学习的需要。针对这一现象,提出了面向e-Learning的概念知识元表征模型,并给出了基于概念知识元的知识组织方法。通过知识元的链接、聚合和融合,形成领域的全局主题图,以描述领域的全局知识结构。为了说明模型的有效性,以教育技术学中的"调查研究法"和初等数学中的"勾股定理"为例,给出了概念知识元的实例,并通过RDF的描述方式,对概念知识元进行了描述和存储。最后探讨了知识元模型在e-Learning中的典型应用,并介绍了基于概念知识元模型的教育技术学科元知识搜索系统。实践证明,该系统在概念学习中能起到良好的辅助作用。 展开更多
关键词 e-learning 知识表征 概念知识元 RDF
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知识管理技术与e-Learning资源库建设研究 被引量:47
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作者 张一春 祝智庭 《电化教育研究》 CSSCI 北大核心 2003年第5期53-58,共6页
资源库是网络化学习的重要基础 ,是教育领域一个全新的增长点。而知识管理是目前在国际管理领域成功运作的一种科学的、高效的管理办法。把知识管理技术引入资源库建设 ,是一种尝试 ,它可以使我们高瞻远瞩 ,清晰地把握资源库建设的方方... 资源库是网络化学习的重要基础 ,是教育领域一个全新的增长点。而知识管理是目前在国际管理领域成功运作的一种科学的、高效的管理办法。把知识管理技术引入资源库建设 ,是一种尝试 ,它可以使我们高瞻远瞩 ,清晰地把握资源库建设的方方面面 ,成功建设与管理 e- L earning资源库。本文从资源库的现状出发 ,剖析和介绍了知识管理技术 ,并用知识管理技术分析 e- L earning资源库建设的几个问题 ,探讨教学资源库建设的途径与方法 ,并对资源库的发展提出了一些看法。 展开更多
关键词 知识管理 KM e-learning 资源库
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学习交互的现状与未来发展——从课堂学习到e-Learning,m-Learning再到u-Learning 被引量:37
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作者 杨刚 徐晓东 《中国电化教育》 CSSCI 北大核心 2010年第7期52-58,共7页
学习交互已成为影响教育活动的关键因素之一。本文以学习环境发展历程作为学习交互的分析视角,以交互作为探讨的经纬,分别从不同学习形式,即从课堂学习,到e-Learning,再到m-Learning,未来发展为u-learning学习来研究交互在教育教学中的... 学习交互已成为影响教育活动的关键因素之一。本文以学习环境发展历程作为学习交互的分析视角,以交互作为探讨的经纬,分别从不同学习形式,即从课堂学习,到e-Learning,再到m-Learning,未来发展为u-learning学习来研究交互在教育教学中的不同表现形式、理论基础和特征等,并对未来学习交互进行了展望。笔者希望通过本文对未来学习交互的探讨,能够引起更多的研究者对此问题的关注,并引发对未来教育改革的思考。 展开更多
关键词 学习交互 e-learning M-LEARNING U-LEARNING 普适技术
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Application of N: P Stoichiometry to Ecology Studies 被引量:88
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作者 张丽霞 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2003年第9期1009-1018,共10页
Stoichiometry has long been addressed in the studies of ecosystem ecology, but it was almost ignored for a long time. Until recently, ecologists have become aware that stoichiometry could provide a new tool to study e... Stoichiometry has long been addressed in the studies of ecosystem ecology, but it was almost ignored for a long time. Until recently, ecologists have become aware that stoichiometry could provide a new tool to study ecology from genes to the biosphere. Among this trend, N:P stoichiometry is used actively in ecological interactions since nitrogen (N) and phosphorus (P) are the two most important elements in most ecosystems. This article reviews the application of N:P stoichiometry to the studies of ecological problems at different levels, including ecosystem, community and species. Meanwhile, we also provide the cellular basis of N:P stoichiometry, identify the shortages in the use of N:P stoichiometry theory, and put forward some perspectives for future research to be conducted. 展开更多
关键词 trophic interaction trophic dynamics ecological interactions nutrient limitation
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