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31.
基于QUEST定量检测1H MRS大脑代谢物的研究 总被引:1,自引:0,他引:1
利用jMRUI时域分析软件模拟先验知识基础集定量检测1H MRS大脑代谢物. 通过模拟短TE=28 ms的1H MRS的多种代谢物基础集,经HLSVD奇异值分解滤除残余水峰,将先验知识应用在QUEST算法上对1H MRS大脑代谢物信号进行定量估计. 结果显示, 基于QUEST能有效获得1H MRS大脑代谢物的估计浓度. 表明引用先验知识基础集进行1H MRS定量分析可克服短TE时谱线复杂和波峰重叠峰等问题,极大地提取代谢物的信息. 相似文献
32.
吴望名 《高校应用数学学报(A辑)》1992,(1)
In this paper, we get several equivalent conditions of some methods on multidimensional (multicon-ditional) fuzzy reasoning. 相似文献
33.
认知心理学理论认为,人的知识与能力的获得实际上就是信息的加工过程,也即是学习者在能力习得过程的对已有经验的刺激反应过程.大学实验不仅培养学生的动手能力,它也是孕育创新能力的培养课程.实验能力与思维方式、年龄、智商、性别、知识积累和培养方式等诸多因素相关,思维方式与思维路径绝对创新力,反之,借助于创新性实验教学可以提高学生的创造性思维. 相似文献
34.
35.
Domain experts have two major advantages over novices with regard to problem solving: experts more accurately encode deep problem features (feature encoding) and demonstrate better conceptual understanding of critical problem features (feature knowledge). In the current study, we explore the relative contributions of encoding and knowledge of problem features (e.g., negative signs, the equals sign, variables) when beginning algebra students solve simple algebraic equations. Thirty-two students completed problems designed to measure feature encoding, feature knowledge and equation solving. Results indicate that though both feature encoding and feature knowledge were correlated with equation-solving success, only feature knowledge independently predicted success. These results have implications for the design of instruction in algebra, and suggest that helping students to develop feature knowledge within a meaningful conceptual context may improve both encoding and problem-solving performance. 相似文献
36.
Beliefs,Practical Knowledge,and Context: A Longitudinal Study of a Beginning Biology Teacher's 5E Unit 下载免费PDF全文
The purpose of this three‐year case study was to understand how a beginning biology teacher (Alice) designed and taught a 5E unit on natural selection, how the unit changed when she took a position in a different school district, and why the changes occurred. We examined Alice's developing beliefs about science teaching and learning, practical knowledge, and perceptions of school context in relation to the 5E unit. Data sources consisted of interviews, classroom observations, and lesson materials. We found that Alice placed more emphasis on the explore phase, less emphasis on the engage and explain phases, and removed the elaborate phase over time. Alice's beliefs about science teaching and learning acted as a filter for making sense of practical knowledge and perceptions of context. Although her beliefs were student centered, they aligned with discovery learning in which little intervention from the teacher is required. We discuss how her beliefs, practical knowledge, and perceptions of context explained the changes in her practice. This study sheds insight into the nature of beliefs and how they relate to the 5E lesson phases, as well as the different lenses for viewing the 5E instructional model. Implications for science teacher preparation and induction programs are discussed. 相似文献
37.
Assessing the Ability of an Online Environment to Facilitate the Critical Features of Teacher Professional Development 下载免费PDF全文
Providing teachers effective professional development (PD) is an ongoing challenge in the field of education. Emergence of technological innovations in the form of computer‐based asynchronous and synchronous communication has provided new opportunities to improve and expand teacher PD opportunities beyond the physical walls of a school. The purpose of this meta‐analysis is to examine the ability of online learning environments to facilitate the critical features of teacher PD identified in Desimone (2009) as content focus, active learning, coherence, duration, and collective participation. Analysis of the 20 empirical studies sought to reveal the purpose of the study, methodologies utilized, and major findings. Multiple studies indicated the ability of an online environment to engage teachers in active learning, collective participation, and content‐focused learning activities. Additionally, the results of this meta‐analysis revealed a lack of empirical studies that have examined the ability of online teacher PD to support the critical features of coherence and duration. Findings of this research have implications for a future research agenda and policy considerations related to online teacher PD initiatives. 相似文献
38.
以真度为基础,给出二值命题逻辑系统中基于前提信息的相似度和伪距离的概念以及伪距离的真度表示式,对二值命题逻辑中具有前提信息的近似推理问题进行讨论. 相似文献
39.
Mathematical definitions are an important mathematical construct which has been noted as a challenging topic for both teachers and students. This study provides an analysis of the form and content of a set of 308 definitions of quadrilateral types provided by 44 novice pre-service elementary teachers (NPSTs) who had not yet studied geometry or definitions on the college level. Analysis of definition structure including necessary, sufficient, and minimal conditions, as well as hierarchical and partitional structure, provides insight into what NPSTs may think about the form of mathematical definitions in general. Analysis of the properties used in definitions of each shape type and the frequency of those properties reveals the shape types with which NPSTs are most and least familiar. These results are presented alongside possible applications and implications for instruction. 相似文献
40.
Sumeyra Dogan Coskun Mine Isiksal Bostan 《International Journal of Mathematical Education in Science & Technology》2019,50(4):486-505
The purpose of this paper is to examine the cognitive demand levels of tasks used by an in-service primary teacher during length measurement and perimeter instruction and to examine a possible link between these tasks and the teacher’s mathematical knowledge in teaching. For this purpose, a case study approach was used and the data was drawn from classroom observations, semi-structured interviews, and field notes. Specific tasks from length measurement and perimeter instruction were presented and analyzed according to the Mathematical Tasks Framework. Then, how these tasks gave information about the teacher’s mathematical knowledge in teaching in the length measurement and perimeter topics was examined according to the Knowledge Quartet model. According to the findings of the study, the tasks used during length measurement and perimeter instruction were mostly categorized as low-level tasks. In addition, teacher’s mathematical knowledge in teaching affected the implementation of the tasks. 相似文献