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131.
132.
In the last decades, many similarity measures are proposed, such as Jaccard coefficient, cosine similarity, BM25, language model, etc. Despite the effectiveness of the existing similarity measures, we observe that none of them can consistently outperform the others in most typical situations. Choosing which similarity predicate to use is usually treated as an empirical question by evaluating a particular task with a number of different similarity predicates, which is not computationally efficient and the obtained results are not portable. In this paper, we propose a novel approach to combine different similarity predicates together to form a committee so that we do not need to worry about choosing which of them to use. Empirically, we can obtain a better result than any individual similarity predicate, which is quite meaningful in practice. Specifically, our method models the problem of committee generation as a 0–1 integer programming problem based on the confidence of similarity predicates and the reliability of attributes. We demonstrate the effectiveness of our model by applying it on three datasets with controlled errors. Experimental results demonstrate that our similarity predicate committee is more robust and superior over existing individual similarity predicates.  相似文献   
133.
STILL TO COME     
The hundredth anniversary of any organization's founding is an occasion for celebration. At the least, one can celebrate the organization's longevity in surviving for a whole century. The organization has to be doing something right to exist that long. The Religious Education Association has done many good things in its hundred years of existence. These things should be remembered and praised.  相似文献   
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Abstract

High school underrepresented minority students in the US are at an increased risk of dropping out of the STEM pipeline. Based on expectancy-value theory, we examined if Latino students’ perception of support from parents, siblings/cousins, teachers, and friends in 10th grade predicted their science ability self-concepts and values, which in turn predicted their classroom engagement. Survey data were collected from 104 Latino high school students and their science teachers. The findings suggest that adolescents’ perceptions of overall support and home-based support predicted adolescents’ science ability self-concepts at 10th grade while controlling for their 9th grade self-concepts. Although adolescents reported high support from teachers, teacher or school-based support alone was not a strong correlate of their motivational beliefs. Perceived support was indirectly related to classroom engagement through adolescents’ ability self-concepts. Feeling supported across home and school may be necessary to sustain adolescents’ science motivational beliefs and, in turn, their science classroom engagement.  相似文献   
136.
Credit and debit cards have spread and skyrocketed all around the world to become the most popular means of payments in many countries. Despite their enormous popularity, cards are not free of risk. Technology development and e-commerce have exponentially increased internal credit card incidents. This paper identifies and quantifies the different types of credit card fraud and puts into question the effectiveness of the role assigned to cardholders in its detection.  相似文献   
137.

Introduction

The validation process is essential in accredited clinical laboratories. Aim of this study was to validate five kinds of serum vacuum tubes for routine clinical chemistry laboratory testing.

Materials and methods:

Blood specimens from 100 volunteers in five diff erent serum vacuum tubes (Tube I: VACUETTE®, Tube II: LABOR IMPORT®, Tube III: S-Monovette®, Tube IV: SST® and Tube V: SST II®) were collected by a single, expert phlebotomist. The routine clinical chemistry tests were analyzed on cobas® 6000 module. The significance of the diff erences between samples was assessed by paired Student’s t-test after checking for normality. The level of statistical significance was set at P < 0.005. Finally, the biases from Tube I, Tube II, Tube III, Tube IV and Tube V were compared with the current desirable quality specifications for bias (B), derived from biological variation.

Results and conclusions:

Basically, our validation will permit the laboratory or hospital managers to select the brand’s vacuum tubes validated according him/her technical or economical reasons, in order to perform the following laboratory tests: glucose, total cholesterol, high density lipoprotein-cholesterol, triglycerides, total protein, albumin, blood urea nitrogen, uric acid, alkaline phosphatise, aspartate aminotransferase, gamma-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, direct bilirubin, calcium, iron, sodium and potassium. On the contrary special attention will be required if the laboratory already performs creatinine, amylase, phosphate and magnesium determinations and the quality laboratory manager intend to change the serum tubes. We suggest that laboratory management should both standardize the procedures and frequently evaluate the quality of in vitro diagnostic devices.  相似文献   
138.
In this article, we focus on a group of 39 prospective elementary (grades K-6) teachers who had rich experiences with proof, and we examine their ability to construct proofs and evaluate their own constructions. We claim that the combined “construction–evaluation” activity helps illuminate certain aspects of prospective teachers’ and presumably other individuals’ understanding of proof that tend to defy scrutiny when individuals are asked to evaluate given arguments. For example, some prospective teachers in our study provided empirical arguments to mathematical statements, while being aware that their constructions were invalid. Thus, although these constructions considered alone could have been taken as evidence of an empirical conception of proof, the additional consideration of prospective teachers’ evaluations of their own constructions overruled this interpretation and suggested a good understanding of the distinction between proofs and empirical arguments. We offer a possible account of our findings, and we discuss implications for research and instruction.  相似文献   
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In this paper, we report findings from a discourse analysis study of reading instruction in eight primary/elementary school classrooms in the United States. Drawing upon discursive psychology, we specifically examined 96 hours of reading comprehension instruction, with a focus on how teachers talked about the body during the instruction and noted how this gave rise to particular constructions of what it means to be a ‘good’ reader and/or learner. We discuss two patterns from the analysis of our data, including: (1) emphasized versus embedded physical control as essential to being a ‘successful’ reader, and (2), implicit physical control and freedom as essential to literacy learning and to students' identities as readers. We conclude by highlighting implications, with a focus on student identity.  相似文献   
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