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181.
The last two decades have witnessed a significant increase in discussions about the different dimensions of knowledge and knowledge management (KM). This is especially true in the construction context. Many factors have contributed to this growing interest including globalisation, increased competition, diffusion of new ICTs (information and communication technologies) and new procurement routes, among others. There are a range of techniques and technologies that can be used for KM in construction organisations. The use of techniques for KM is not new, but many technologies for KM are fairly new and still evolving. This paper begins with a review of different KM techniques and technologies and then reports the findings of case studies of selected U.K. construction organisations, carried out with the aim of establishing what tools are currently being used in U.K. construction organisations to support knowledge processes. Case study findings indicate that most organisations do not adopt a structured approach for selecting KM technologies and techniques. The use of KM techniques is more evident compared to KM technologies. There is also reluctance among construction companies to invest in highly specialised KM technologies. The high costs of specialist KM technologies are viewed as the barrier to their adoption. In conclusion, the paper advocates integrated use of KM techniques and technologies in construction organisations.  相似文献   
182.
The assessment of nutrition and activity in athletes requires accurate and precise methods. The aim of this study was to validate a protocol for parallel assessment of diet and exercise against doubly labelled water, 24-h urea excretion, and respiratory gas exchange. The participants were 14 male triathletes under normal training conditions. Energy intake and doubly labelled water were weakly associated with each other (r = 0.69, standard error of estimate [SEE] = 304 kcal x day(-1)). Protein intake was strongly correlated with 24-h urea (r = 0.89) but showed considerable individual variation (SEE = 0.34 g kg(-1) x day(-1)). Total energy expenditure based on recorded activities was highly correlated with doubly labelled water (r = 0.95, SEE = 195 kcal x day(-1)) but was proportionally biased. During running and cycling, estimated exercise energy expenditure was highly correlated with gas exchange (running: r = 0.89, SEE = 1.6 kcal x min(-1); cycling: r = 0.95, SEE = 1.4 kcal x min(-1)). High exercise energy expenditure was slightly underestimated during running. For nutrition data, variations appear too large for precise measurements in individual athletes, which is a common problem of dietary assessment methods. Despite the high correlations of total energy expenditure and exercise energy expenditure with reference methods, a correction for systematic errors is necessary for the valid estimation of energetic requirements in individual athletes.  相似文献   
183.
Previous research has demonstrated the potential of examining log-file data from computer-based assessments to understand student interactions with complex inquiry tasks. Rather than solely providing information about what has been achieved or the accuracy of student responses (product data), students' log files offer additional insights into how the responses were produced (process data). In this study, we examined students' log files to detect patterns of students' interactions with computer-based assessment and to determine whether unique characteristics of these interactions emerge as distinct profiles of inquiry performance. Knowledge about the characteristics of these profiles can shed light on why some students are more successful at solving simulated inquiry tasks than others and how to support student understanding of scientific inquiry through computer-based environments. We analyzed the Norwegian PISA 2015 log-file data, science performance as well as background questionnaire (N = 1,222 students) by focusing on two inquiry tasks, which required scientific reasoning skills: coordinating the effects of multiple variables and coordinating theory and evidence. Using a mixture modeling approach, we identified three distinct profiles of students' inquiry performance: strategic, emergent, and disengaged. These profiles revealed different characteristics of students' exploration behavior, inquiry strategy, time-on-task, and item accuracy. Further analyses showed that students' assignment to these profiles varied according to their demographic characteristics (gender, socio-economic status, and language at home), attitudes (enjoyment in science, self-efficacy, and test anxiety), and science achievement. Although students' profiles on the two inquiry tasks were significantly related, we also found some variations in the proportion of students' transitions between profiles. Our study contributes to understanding how students interact with complex simulated inquiry tasks and showcases how log-file data from PISA 2015 can aid this understanding.  相似文献   
184.
The aim of this study was to develop a measurement instrument which is compatible with literature, of which validity and reliability are proved with the aim of determining interaction perceived by learners in online learning environments. Accordingly, literature review was made, and outline form of the scale was formed with item pool by taking 14 expert opinions. As a result of exploratory factor analysis of data obtained from participation of 177 learners from eight different universities, it was seen that the scale consisted of 30 items and 3 dimensions. These dimensions are learner–content interaction, learner–instructor interaction and learner–learner interaction. Cronbach Alpha reliability coefficient of the whole scale was .95. Confirmatory factor analysis showed that fit indexes of the structure provided a good and acceptable fit. Based on these findings, Perceptions of Online Interaction Scale is a valid and reliable tool that may be used in measuring interaction occurring in online learning environments.  相似文献   
185.
186.
Spatial abilities vary during the menstrual cycle. The effects of a similar rhythm in men are unknown. Mental rotation and spatial visualization of young healthy volunteers (29 females and 31 males) were tested during the menstrual and periovulatory phase of the menstrual cycle in women, and during the low-testosterone and high-testosterone phases of the circatrigintan rhythm in men in random order. Men outperformed women in both tests. In women, higher scores were achieved during the periovulatory phase, in men during the low-testosterone phase. The correlation between actual salivary testosterone levels and spatial abilities were positive in women and negative in men. According to our knowledge, this is the first study showing effects of a male infradian rhythm on cognitive abilities.  相似文献   
187.

Introduction:

Non insulin dependent diabetes mellitus is the most common type of diabetes. Genetic factors, lipid profiles, hypertension are potential risk factors for diabetes mellitus. Adenosine binding cassette transporter proteins 1 (ABCA1) plays a role in cholesterol metabolism, especially high density lipoprotein (HDL-cholesterol). There are multiple mechanisms by which HDL-cholesterol can be atheroprotective, it is clear that the relative activity of ABCA1 plays a major role. We aimed to investigate association of ABCA1 C69T gene polymorphism with lipid levels in Turkish type 2 diabetic patients.

Materials and methods:

After isolation of DNA by ethanol precipitation we determined ABCA1 gene polymorphism by using polimerase chain reaction - restriction fragment lenght polymorphism (PCR-RFLP) method in 107 type 2 diabetic patients and 50 healthy controls.

Results:

We have observed that the frequency of TT genotype is significantly higher in healthy controls compared to patients (14% vs. 3%; P = 0.008). Also frequency of T allele was higher in controls than in patients (34% vs. 21%; P = 0.020; OR (95% CI) = 0.52 (0.30–0.88)). There was no association of lipid levels and ABCA1 C69T polymorphism subgroups.

Conclusion:

We have found significantly higher frequency of both T allele and genotype in control group when compared to patients that made us think that T allele may be a protective factor against diabetes mellitus. But, we could not find a relationship between genotypes and lipid concentrations in our two groups. Larger studies will help us to understand the relationship between ABCA1 C69T genotype and lipid parameters in diabetes mellitus.  相似文献   
188.
The primary aim of this study was to examine the reliability and validity of a Turkish version of the Distance Education Learning Environment Survey (DELES) in post-secondary distance education. The second aim was to investigate empirically the conceptualisation of the distance education learning environment as a singular latent construct, within a second-order factorial structure that consists of six first-order factors. The DELES is a 34-item instrument for assessing social-psychological perceptions among distance education students. The tested hypotheses concerned key antecedents and consequences of the factorial structure of DELES in the Turkish context using confirmatory factor analyses. Principal component analysis of the Turkish data revealed six main factors of interest, which corresponded to the hypothesised constructs in the original DELES. The data suggested good reliability and validity for the Turkish DELES (DELES-TR) relative to the original version. Further, second-order analyses were conducted with two complementary samples to demonstrate the validity of six dimensions of the DELES-TR and their contributions to an overall factorial structure of social-psychological learning environment in distance education. Initial support for the second-order factorial validity of DELES-TR was found. Results indicate that a dimensional model of DELES-TR with the six first-order factors provided a superior fit to the data than first-order DELES-TR with six factors. Additionally, an investigation was conducted regarding associations between the DELES-TR’s psychosocial scales and a student satisfaction scale. This study is unique in its focus on the learning environment in distance education in the Turkish setting.  相似文献   
189.
Stone consolidation is one of the major restoration treatments used for historical monuments preservation. A natural stone is a complicated heterogeneous porous system making the process of consolidation dependent on many variables. In practical restoration aims, for a given stone type, the selection of a suitable consolidant and consolidation conditions therefore remains a complex issue. The impregnation depth is a key factor for the assessment of the treatment efficiency. The combination of state-of-the-art hybrid pixel semiconductor detectors with newly available micro-focus X-ray sources makes possible to apply X-ray radiography, an ideal non-destructive tool, for penetration depth monitoring. In this study, high-resolution X-ray radiography is used for monitoring the penetration depth of organosilicon consolidants in the Opuka stone. The penetration depth has been evaluated in relation to the time of consolidation, stone porosity and consolidation mixtures properties. The exact influence of the X-ray contrast agent on the consolidation depth has been investigated as well. The information obtained provides supplementary knowledge on the suitability of investigated products for the treatment of this type of stone. In our study, the capabilities of X-ray radiography have been demonstrated on X-ray radiography simple projections, high-resolution computed tomography (CT) as well as on the dynamic processes monitoring. The results thus can serve also as an instrumental and methodological example applicable for consolidation monitoring of other stone types.  相似文献   
190.
This article reviews the policies for disadvantaged children in western countries since the mid‐sixties. First, it analyses the design and results of the ‘classic programmes’ of positive discrimination such as the American Title I programme, and the English, Dutch, Flemish and French priority areas policies. It discusses the differences and similarities in approach and the disappointing results. Second, the article explores some of the ‘alternatives’ such as pre‐schooling, reducing class size, restructuring the school year, and teacher incentives.  相似文献   
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