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981.
针对现有自主学习和合作学习模式的不足,提出了大学英语"自主-合作学习"模式。该模式将学习目标、任务特质、学生认知风格、合作动机以及学习情境五个要素作为输入,教师教学、学生自主和合作学习几个环节的整合作为过程,以教学设计、教学实施和学习绩效作为输出,对大学英语教学模式的各要素、环节和结果及其关系予以整体、全面的探讨。模式结合了自主学习和合作学习两者的优势,克服了单一模式的不足,充分发挥教学模式的多重功能,为该模式的实施提供了一个概念框架。 相似文献
982.
983.
近年来基于字典学习的超分辨率重建技术已成为图像处理领域的研究热点,相比基于重建的超分辨率方法,基于学习的方法充分利用了先验知识,在放大倍数较高时,仍可取得较好的效果,因此被公认为一种非常有前途的方法。本文对国内外已有的基于字典学习的超分辨率重建方法进行了系统研究,梳理了3种基于字典学习超分重建算法的基本原理及优缺点。此外,本文根据遥感影像的特点,使用同一数据源进行字典学习,利用不同字典学习算法分别生成高、低联合字典对,采用不同尺寸大小及缩放倍数的测试图像,进行超分辨率重建,对各种算法的重建性能、鲁棒性和复杂度进行综合分析,进一步研究了各种算法对遥感影像不同应用需求的适用性。 相似文献
984.
985.
《Marine Policy》2017
This short communication piece presents guidelines and challenges for organizing fisheries learning exchanges (FLEs). Non-governmental organizations, government agencies, and resource users use FLEs to share best practices and bridge knowledge gaps between small-scale fishing communities and stakeholder groups. Even though FLEs are widely used and have numerous cited benefits, there are challenges associated with planning and implementing FLEs. To overcome these challenges and maximize FLEs’ effectiveness, the authors describe guidelines for FLE organizers. The guidelines are based on the perspectives of over 20 FLE experts collected during 2013 through questionnaires, interviews, discussions, and surveys. The guidelines include steps that organizers should take before, during, and after a FLE. For instance, there was broad consensus that before a FLE, it is important to select a diverse group of participants, including both conservation advocates and critics, and to create an exchange agreement outlining the roles and responsibilities of participants. During a FLE, cultural activities and daily reflections by participants are valuable to the exchange process. After a FLE, activities that formalize the participants’ involvement in the FLE are important, such as welcome-home ceremonies and participation certificates. Follow-up support for FLE participants is perceived as an essential step in the FLE and should be included in the FLE's budget. Finally, challenges in organizing FLEs are explicitly described and potential solutions to overcome those challenges are provided. The authors researched and compiled these guidelines and challenges to inform and improve the increasingly widespread use of FLEs. 相似文献
986.
面向对象的喀斯特地区石漠化遥感信息提取研究——以贵州省大方地区为例 总被引:1,自引:1,他引:0
针对现有基于像素的监督和非监督分类方法在地质环境复杂、地形起伏较大、阴影明显的喀斯特石漠化地区难以满足石漠化信息提取精度要求的问题,采用基于纹理特征数据和地形数据辅助面向对象方法进行喀斯特地区石漠化信息的提取。该方法首先依据石漠化分布在TM/ETM+影像面积大小不均匀的特征,利用纹理和地形因子计算最优分割参数进行多尺度分割;然后根据植被覆盖率、岩石裸露率以及坡度因子构建石漠化分级指标;最后参照石漠化分级标准、光谱信息以及纹理特征等建立的分类规则提取喀斯特地区石漠化信息。选取贵州省石漠化严重的大方县时序TM/ETM+影像进行石漠化信息提取试验,结果表明:与基于像素的监督分类和非监督分类方法相比,基于面向对象的分类可以有效地减少因复杂地形导致石漠化信息提取结果"椒盐化"现象,提取精度明显优于基于像素的监督分类和非监督分类方法。 相似文献
987.
高斯过程机器学习在边坡稳定性评价中的应用 总被引:2,自引:1,他引:1
针对边坡工程是复杂的非线性系统,采用常规的理论分析和数值计算方法难以满足对边坡稳定性评价的高精度与快速性的要求,为此,提出对处理非线性复杂问题具有很好的适应性一种有概率意义的核学习机--高斯过程机器学习方法来解决边坡稳定性的合理评价问题,建立了相应的边坡稳定性预测模型。工程应用研究结果表明,采用高斯过程机器学习方法进行边坡稳定性评价是科学可行的,该方法能很好地表达边坡稳定性与各影响因素之间的非线性映射关系,能方便快捷地给出合理可靠且具有概率意义的边坡稳定状态评价结果,为实现边坡快速设计的工程实践要求提供了一条新的途径。 相似文献
988.
基于组合核函数的高斯过程边坡角智能设计 总被引:2,自引:0,他引:2
高斯过程(GP)是近年来发展迅速的一种全新学习机。与支持向量机(SVM)相比,该方法有着容易实现、超参数可自适应获取及预测输出具有概率意义等优点。结合边坡工程中的边坡角设计,编写了在多种因素影响下边坡角设计的GP程序,为克服单一核函数预测精度和网络泛化能力差的缺点,采用单一核函数相加作为GP的组合核函数,将自动关联性测定参数(ARD)引入其中,建立了关于超参数的GP回归网络模型,使用共轭梯度下降算法导出最优超参数,用ARD超参数进行输入属性相关性分析和特征选取,并以此网络对测试样本进行学习预测,结合支持向量回归方法给出了在回归问题上的应用和对比分析。结果表明:在边坡角智能设计应用中,采用组合核函数的GPR网络ARD参数具有明确的物理意义,预测回归性能优于SVM,且预测输出的概率解释能更好的体现预测值的代表性,为边坡角设计开辟新径。 相似文献
989.
Lost in the field: ensuring student learning in the 'threatened' geography fieldtrip 总被引:1,自引:0,他引:1
Clare Herrick 《Area》2010,42(1):108-116
As a result of its importance to the discipline's identity and epistemology, the nature of fieldwork and the fieldtrip itself have recently come under close scrutiny in the education and geographical literature. Moreover, not only is their pedagogical importance being debated, but also their future viability at a time of increasing pressure on institutions to minimise potential risk situations in the field, offer value for money to students as well as following the increasingly common and popular trend of long-haul fieldtrips. This paper therefore critically interrogates the role and use of fieldwork within geographical teaching and learning in the light of its changing and increasingly contested status within the discipline in three parts. First, it outlines and reflects upon the current debate surrounding the threat to the primacy of fieldtrips in geography at a time of ongoing upheaval in higher education. Second, through the empirical example of personal experiences teaching on second-year undergraduate urban geography fieldtrips to San Francisco in December 2007 and 2008, the paper engages with the current discussions of the pedagogical importance of fieldtrips. Third, the paper asks, to what extent teaching in 'the field' might foster the 'experiential' or 'active' learning needed to inspire the kind of 'deep learning' approaches that hold the kind of 'transformative' potential envisaged as a key goal of education more broadly. Through exploring these ideas with reference to recent and relevant experience, the paper aims to critically interrogate the role and value of fieldtrips at a time when their potential demise is being cast as a fundamental assault on geography's founding identity and pedagogical traditions. The paper concludes that despite the threats it faces, the pedagogical significance of fieldwork means that it must remain a fundamental tenet of the geographical educational experience. 相似文献
990.
John Kinniburgh 《New Zealand geographer》2010,66(1):74-84
The development of the revised New Zealand Curriculum provides an excellent opportunity to investigate GIS-based learning pedagogies within the social sciences classroom. The new curriculum privileges inquiry-based activities with a more participatory approach to learning, providing students with greater autonomy in their studies. This paper emphasises the value of GIS technology for extending student learning when situated within a problem-based learning (PBL) framework. Using GIS, students undertake geographic inquiry through meaningful learning grounded in constructivist learning theory. PBL is well suited as an instructional strategy for integrating GIS as students actively learn when presented with authentic, real-world problems. 相似文献