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This paper extends the line of research attempting to link innovation to economic growth by addressing some unexplored questions. Using global patent data, this paper empirically investigates the importance of both the quantity and quality of innovation on economic growth, controlling for past measures of inventive inputs. Moreover, our research examines how innovation inputs can be translated into per capita growth under the various economic structures and stages of economic development. Based on a sample of 58 countries for the period 1980–2003, our empirical results indicate that countries hosting firms with higher quality patents also have higher economic growth. Furthermore, we have some evidence that those countries that increase the level of patenting also witness a concomitant increase in economic growth.  相似文献   
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The main purpose of this study was to explore the factors mediating the translation of second grade teachers’ nature of science (NOS) views into classroom practice after completing a graduate level NOS course. Four second grade in-service elementary teachers comprised the sample of this study. Data were collected from several sources during the course of this study. The primary data sources were (a) assessment of the elementary teachers’ NOS views before and after the graduate level NOS course using the Views of Nature of Science Questionnaire Version B (VNOS-B) (Lederman et al., 2002) coupled with interviews, and (b) a classroom observation and videotaped recording of the elementary teachers’ best NOS lessons coupled with interview. We identified three distinct but related factors that mediated the translation of NOS views into classroom practice: the teachers’ perspectives about the developmental appropriateness of the NOS aspect, the teachers’ selection of target NOS aspects, and the relative importance placed by teachers on each NOS aspect.  相似文献   
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The objectives of the study were to validate a substantiated Teacher Change Beliefs Model (TCBM) and an instrument to identify critical components of teacher change beliefs (TCB) in Malaysian secondary schools. Five different pilot test approaches were applied to ensure the validity and reliability of the instrument. A total of 936 teachers from 47 high-performing secondary schools completed the survey. Structural equation modelling was applied to test the models. Exploratory factor analysis was employed to identify the underlying factors, whereas confirmatory factor analysis was applied to test the measurement models. The analysis yielded a three-factor TCBM: (1) discrepancy, (2) efficacy and (3) principal support. The results demonstrated a good fit of the model: normed χ2 = 3.156, Tucker-Lewis Fix Index = .987, Comparative Fix Index = .991 and Root Mean Square Error of Approximation = .048. The results also provided evidence for convergent validity, discriminant validity and construct reliability. The TCBM is an empirically tested model derived in a local Malaysian cultural education setting. It provides direction for practitioners in planning and designing training programmes of change management for school principals in the enhancement of TCB among teachers in schools. Besides, Teacher Change Beliefs Scale is a promising and welcome tool for both practitioners and researchers. With only nine items, it is easy to administer and not time-consuming.  相似文献   
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The robust stabilization of some classes of nonlinear delay systems with nominal linear delay system is addressed. The form of the controller is not an a priori proposal, but it is the result of a synthesis relying on the use of complete type Lyapunov–Krasovskii functionals, leading to distributed delay linear or nonlinear robust control laws. Simulation results of the stabilization of a chemical refining process demonstrate the good performance of the proposed approaches.  相似文献   
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Farm programmes (FPs) of varied categories have been developed and aired over several decades by Bangladesh Betar, the national radio of Bangladesh for the diffusion of farm technologies. The study aimed to produce an in-depth academic evaluation of their effectiveness in educating farmers in Bangladesh. A sample of 465 respondents from the Khulna and Rajshahi divisions in Bangladesh was randomly selected for a questionnaire survey. To analyse the data, relevant documents were collected from the Ministry of Information, the Ministry of Agriculture, and the Ministry of Fisheries and Livestock of Bangladesh. Frequency distribution, z-test, and binary logistic regression analysis were used as statistical tools. The farm knowledge levels of the farmers were considered the predictors for evaluating the effectiveness of FPs. The results revealed that 93.33% of the sample did not listen to the FPs, while only very few of the listeners listened regularly. Despite this, at the ‘weak’ and ‘average’ levels of knowledge significant differences were noted between listener and non-listener farmers of FPs. The binary logistic regression analysis (Model 1) identified that the farmers who listened to the FPs were likely to acquire farm knowledge 6.62 times more than the farmers who did not listen to the FPs. The farmers who listened to the FPs were likely to have farm knowledge 2.64 times more than the farmers who did not listen to the FPs but consulted with other sources of farming information (Model 2). Similarly, a listener of FPs with farm training was likely to acquire farm knowledge 5.76 times more than a non-listener with farm training (Model 3). The FPs were found to be very effective and could be used to better complement other mechanisms for educating farmers. Regular access to the FPs ought to be ensured through appropriate stimulants for the diffusion of farm technologies.  相似文献   
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Priya Hasan 《Resonance》2017,22(3):213-224
This article will briefly review the theory of star formation (SF) and its development using observations. This is very relevant in the present context since planet formation appears to be a by-product of SF, and the whole question of life in the universe and its origin can be viewed with a new perspective.  相似文献   
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The task of answering complex questions requires inferencing and synthesizing information from multiple documents that can be seen as a kind of topic-oriented, informative multi-document summarization. In generic summarization the stochastic, graph-based random walk method to compute the relative importance of textual units (i.e. sentences) is proved to be very successful. However, the major limitation of the TF*IDF approach is that it only retains the frequency of the words and does not take into account the sequence, syntactic and semantic information. This paper presents the impact of syntactic and semantic information in the graph-based random walk method for answering complex questions. Initially, we apply tree kernel functions to perform the similarity measures between sentences in the random walk framework. Then, we extend our work further to incorporate the Extended String Subsequence Kernel (ESSK) to perform the task in a similar manner. Experimental results show the effectiveness of the use of kernels to include the syntactic and semantic information for this task.  相似文献   
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The set of papers [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999) deals with the behavior of the uniform two-dimensional cellular automata over binary fields (Z2). Some structural properties and precise mathematical models using matrix algebra over the field Z2 are reported for characterizing the behavior of two-dimensional nearest neighborhood linear cellular automata with null and periodic boundary conditions [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999). In this paper, we characterize two-dimensional linear cellular automata transformations by using matrix algebra built on Z3. We analyze some results for two-dimensional CA with rule numbers 2460N and 2460P. Finally, we investigate the dimension of the kernel of two-dimensional cellular automata defined by the rule number 2460N.  相似文献   
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