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141.
In this paper we introduce a novel approach, relying on intelligent engineering, whereby the maximum speed limit at which vehicles on the road can cruise is controlled from some central or distributed facility. The system, as designed, leverages the use of the ubiquitous cellular infrastructure to cut down the costs involved that would otherwise accrue as a result of the need to build a dedicated traffic control system.In the new system maximum speed limits are transmitted from a Central Control Facility (CCF) to all stretches of roads and highways dispersed across urban areas in a highly dynamic manner. The system uses information arriving via a dynamic feedback system on prevailing weather conditions, road conditions, and bulk of traffic, amongst others, before it would broadcast maximum speed limit information to various destinations. When deployed in its final release, this will be done using a highly automated system with little human intervention.The work presented in this paper elaborates the TTC Network Design and RSU Network Distribution for the Tele-Traffic Speed Control System, to remotely manage, enforce, and control the maximum speed limit allowed on road stretches in rural and urban areas for different vehicle categories.The new system has been deployed successfully in a laboratory controlled environment on three vehicle categories; one category representing passenger vehicles, another buses and commuter transport, while the third representing trucks and freight traffic. It is expected that when the system is fully deployed on the wireless infrastructure, speed-related traffic accidents will witness a drop by more than 65-70% according to known accident statistics.  相似文献   
142.
Taxonomy of e-readiness assessment measures   总被引:1,自引:0,他引:1  
To benefit from the advantages of information society, on the one hand, and to be afraid of being left further behind by Global Society and the increase in the digital divide, on the other hand, stimulate countries to be part of Global Information Society. These issues have led policymakers to move towards such a society by identifying the objectives, goals and targets. Planning to achieve these objectives needs a real understanding of the current situation, which is obtained by e-readiness assessment measures. There has been a proliferation of e-readiness assessment measures in recent years that each one has a certain objective. This paper elaborates on and categorizes these measures that help scholars and policymakers to (1) select the measures that fit in with their objectives, (2) prevent the repetitive research, (3) identify the defects and flaws of previous measures and correct them in their own measures, and (4) use the experiences of previous measures to construct their own ones. Based on definitions, objectives, dimensions, methods and approaches, in this paper, the measures are categorized and finally, a measure for e-readiness assessment is presented. Since this measure is a convergence of e-readiness assessment measures, the experienced modelers have consensus on it and it is more suitable to measure e-readiness of countries. Also, it can be exploited as the basis and standard for internationally comparable information society statistics.  相似文献   
143.
A fast and efficient page ranking mechanism for web crawling and retrieval remains as a challenging issue. Recently, several link based ranking algorithms like PageRank, HITS and OPIC have been proposed. In this paper, we propose a novel recursive method based on reinforcement learning which considers distance between pages as punishment, called “DistanceRank” to compute ranks of web pages. The distance is defined as the number of “average clicks” between two pages. The objective is to minimize punishment or distance so that a page with less distance to have a higher rank. Experimental results indicate that DistanceRank outperforms other ranking algorithms in page ranking and crawling scheduling. Furthermore, the complexity of DistanceRank is low. We have used University of California at Berkeley’s web for our experiments.  相似文献   
144.
Free iron in serum has been found in several disease conditions including diabetes. In the present work, we studied the relationship between free iron, fasting blood glucose (FBG) and glycated haemoglobin (HbA1c). Study was carried out on 50 type 2 diabetes cases under poor glycemic control associated with complications, 53 type 2 diabetes cases under good glycemic control and 40 healthy controls. We estimated free iron, both ferrous (Fe+2) and ferric (Fe+3) form, protein thiols, lipid hydroperoxides, FBG, HbA1c and serum ferritin levels in serum. There was a significant increase in free iron in Fe+3 state (p <0.01), HbA1c (p<0.01), serum ferritin (p<0.01), lipid hydroperoxides (p<0.01) and significant decrease in protein thiols (<0.01) in diabetes cases under poor glycemic control compared to diabetes cases under good glycemic control and healthy controls. Free iron correlated positively with HbA1c (p<0.01). Poor glycemic control and increase in glycation of haemoglobin is contributing to the increase in free iron pool which is known to increase oxidant generation.  相似文献   
145.
There is growing evidence that damage to spermatozoa by reactive oxygen species play a key role in male infertility. The aim of this study was to assess seminal plasma free 8-Isoprostane levels in men with asthenozoospermia, asthenoteratozoospermia and oligoasthenoteratozoospermia compared to normozoospermic males and its correlation with seminal parameters. The case group consisted of men with asthenozoospermia (n=15), asthenoteratozoospermia (n=16) and oligoasthenoteratozoospermia (n=15). The control group consisted of 16 males with normozoospermia. After Purification of Free 8-Isoprostane by affinity column, its concentration was measured by enzyme immunoassay method. Free 8-Isoprostane evaluation showed significantly greater values in the total case group (n=46) versus control group (18.23±3.56 vs 2.6±0.38 ng/ml). In each case group free 8-Isoprostane also showed a significant increasing compared to normozoospermic males. Free 8-Isoprostane showed an inversely significant correlation with sperm motility and sperm morphology. Lipid peroxidation could have significant role in etiology of sperm abnormalities. Measurement of 8-Isoprostane can be used as a specific biomarker for assessing lipid peoxidation in sperm.  相似文献   
146.
The data used in this paper were derived from a larger project which had the aim of critically evaluating the Turkish vocational education system on a number of different levels. This article examines the administrative and organisational practices in a selected group of secondary vocational schools in Turkey from the point of view of school administrators, teachers and industrial managers. The results indicate that the Turkish vocational education system is characterised by a centralised, top-down bureaucracy, which inhibits innovative capacity. The authors argue that a degree of decentralisation is necessary at various levels of the system.  相似文献   
147.
ABSTRACT

This study aimed to present a model of intercultural communicative competence (ICC) by incorporating international posture, motivational disposition (ideal L2 self), second language (L2) self-confidence, and metacognitive learning strategies. To this end, 150 Iranian L2 learners, selected through convenience sampling procedure, took part in the research. The findings of structural equation modelling revealed that the proposed model showed adequate fit to the data, implying that the model is appropriate in Iranian English as a foreign language (EFL) context. Also, the results indicated that learners with a high level of international posture are more likely to bridge the gap between their present and ideal selves. This was, additionally, argued that internationally oriented and ideally motivated learners become confident of their abilities to get engaged in interaction with L2 target communities. Furthermore, metacognitive learning strategies were found to be directly associated with ICC, implicating that the learners who continuously reflect on their learning and evaluate their performances are more prone to have a higher level of ICC. Finally, suggestions were offered for language teachers and policy-makers to inspire their learners to be more competent in communication with people of other cultures and languages.  相似文献   
148.
Purpose: A systematic review was conducted to identify facilitators and barriers to movement integration (MI) in elementary school classrooms. Method: Online databases (Educational Resources Information Center, Google Scholar, PsycINFO, and PubMed) served as data sources for the study. Following the PRISMA guidelines, relevant published research on MI was identified and screened for inclusion in a qualitative synthesis. Content analysis of the included articles (N = 28) was used to identify themes of MI facilitators and barriers. Facilitators and barriers were then categorized using a social-ecological framework. Results: A total of 12 themes of MI facilitators and barriers were identified and categorized into two social-ecological levels: institutional factors (e.g., administrative support, resources) and intrapersonal factors (e.g., teacher confidence, ease of implementation). Conclusion: This review can inform research and practice aimed at supporting the implementation of MI in elementary classrooms.  相似文献   
149.
150.
Although luster potteries are frequently excavated at archeological sites in Iran, a thorough scientific study of their provenance has not yet been performed. In this work, 43 pieces of Iranian luster pottery (bowl, dish and tile) excavated from Rayy, Kashan, Maragheh, Alamoot, Takht-i-Sulayman and Jiroft were analyzed in order to investigate their origin. The luster shards which belong to Seljuks and Il-Khanids dynasties (12th–13th centuries) were analyzed using proton induced X-ray emission (PIXE) technique. To classify the fragments according to their location and origin, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to the chemical compositions of the body of the shards. We were able to classify the samples into three distinct groups using PIXE.  相似文献   
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