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11.
Abstract

Adults constitute a continually increasing proportion of students at two-year colleges. While adult students presumably have special needs, little is known about them. This study focused on the characteristics and needs of 17,137 students enrolled in 100 randomly selected two-year colleges across the country, separately for different age levels. Using a wide variety of variables collected at entrance, after one term, at graduation, and three years after graduation, differences by sex among the following four age groups were ascertained: age 19 or younger, 20–24, 25–39, and 40 or older. Major trends with age, differences among age groups, and interactions between age and sex were found for a number of variables: abilities, grades, attrition, self-perceptions, aspirations and goals, competencies, job values and preferences, satisfaction with and rating of various aspects of the college, expressed needs for help, extracurricular participation, outside work during school, postgraduate jobs obtained and how obtained, job satisfaction, percent going to and graduating from four-year programs, and preference for entering a two-year program if they had to do it all over again. Adult students do have many special needs that vary with age level. We think a repeat of the study but comparing across other groupings of adults would be desirable, even though extreme diversity also exists within such groups. Another consideration is that many new kinds of adult students will in the future be entering postsecondary education in large numbers.  相似文献   
12.
Mismatched uncertainty and chattering appear as two challenges in sliding mode control. To overcome the problem of mismatched uncertainty, multiple sliding surfaces with virtual inputs are proposed. Accordingly, we have proposed two new methods based on designed neural observer: sliding mode control (SMC) and dynamic sliding mode control (DSMC) methods. Although, the proposed SMC can significantly cope with the mismatched uncertainties, but it suffers from chattering phenomenon. The chattering problem can be removed in DSMC, because an integrator is placed before the system. This results in increased number of the system states. This new state can be identified with the proposed neural observer. Note that in both proposed approaches, the robust performance (invariance property) of system is reserved, even in the presence of mismatch uncertainties. Then, to have a valid comparison the proposed DSMC is also designed using loop transfer recovery observer (LTRO). This comparison shows the good performance of the DSMC based neural networks. Moreover, the upper bound of uncertainties is not used in SMC and DSMC controllers and also in the neural observer and LTRO, which is important in practical implementation. Finally, comparing the equations, one can see the simplicity of DSMC in concept and also in realization.  相似文献   
13.
Adult benefits for participants in Project CARE were compared with those of the Abecedarian Project, a closely related randomized study of early childhood educational intervention for children from low-income families who were at risk of developmental delays and school failure. CARE replicated Abecedarian's young adult treatment-related educational and vocational attainment gains. CARE data also supported the Abecedarian reduction in marijuana use. Treated individuals in both studies reported adopting a more active life style. The average age at birth of a first child, the number of children, and the proportion of teen parents were positively affected in the Abecedarian sample but not in CARE. Finding significant educational and vocational gains lasting into young adulthood in the CARE study reinforces Abecedarian young adult findings and strengthens the case for early childhood intervention for children from low-income families.  相似文献   
14.
15.
This paper examines alternative techniques for projecting freshman enrollment in specific academic departments. Departmental enrollment projections provided by four different projection models are compared to actual departmental enrollments at a selected institution. Two of the models use only historical data, while the other two models are sensitized to current developments as indicated by the expressed major choices of prospective freshmen. The use of discriminant analysis to establish differential enrollment probabilities is also explored.Although different models do a better job for different curricular departments, the smallest mean squared error across all departments was obtained with the simplest projection technique. The use of the preliminary major choice of prospective freshmen did not improve departmental projections, and the student characteristics explored in this study did not differentiate enrolled from non-enrolled students adequately enough to improve enrollment projection accuracy.Based on the results obtained at this one institution, therefore, it would appear that simple and straightforward projection models can be as useful as complex and sophisticated models.This is an expanded version of an earlier paper read at the 1971 Association of Institutional Research Forum in Denver, Colorado.  相似文献   
16.
The association between time devoted to homework and children's academic achievement has long been an issue of great debate. A small number of mainly correlational studies have been conducted into this issue in a primary school setting, but have produced somewhat mixed results. In this paper we contribute to this literature by investigating the relationship between time spent upon homework and children's outcomes across 24 countries. By using a student fixed-effects approach, capturing differences in homework time amongst the same student across different school subjects, we argue that our results are likely to be subject to less confounding than much of the existing literature. We find little evidence that the amount of homework time primary school children are assigned is related to their academic achievement. This holds true across a large number of countries, survives various robustness tests and does not vary by gender or socio-economic status. We interpret this finding as suggesting that the homework assigned to primary school pupils may not be adequate to produce a positive association, and needs be improved if this time-consuming activity is ever going to bring benefits for children's academic achievement.  相似文献   
17.
Although Communities of Practice have become a core concept in understanding how knowledge is managed within organizations, there have been few studies of the praxis of formation of Communities of Practice. In this article, we report on a Grounded Theory study of the members of a previously identified Community of Practice within the UK Higher Education Academy Psychology Network. In addition to providing data on the functioning of the community, the study also revealed a hitherto unrecognized form of community that exhibits all of the characteristics of CoPs yet has only a transient existence that seems to nucleate around an existing core community. Drawing on the metaphor of quantum behaviour, we termed these communities Quantum Communities of Practice. We describe a theory to explain this phenomenon that is grounded in the data from the study. We conclude by discussing the value and validity of our findings and methodology and indicating the next steps we will take in our research.  相似文献   
18.
Objective: To analyze the possible dose-response association between components of sports participation (intensity, volume and previous engagement) and 4-year mortality rates among Brazilian adults.

Methods: 679 males and females (mean age among men = 66.7 ± 9.3 years old and mean age among women = 64.8 ± 8.9 years old) composed the study sample. Sports participation was assessed using Baecke’s questionnaire, which considers intensity, duration and previous engagement. Medical records were used to identify the cause of the death. Cox regression analysis was performed to determine the independent associations of exercise components and mortality.

Results: Participants that reported exercising at moderate-vigorous intensity (Moderate/vigorous: 4.1% versus None/light: 10.3% [p-value = 0.012]; HR = 0.42 [0.1 to 0.94)] and for more than four months (≥4 months: 5.3% versus <4 months: 10.2% [p-value = 0.038]; HR = 0.47 [0.24 to 0.94]) had lower mortality risk. The percentage of survival according to all-cause mortality was significantly higher for participants engaged in sports at moderate-vigorous intensity (p-value = 0.014), as well as for those engaged in sports for periods superior than four months (p-value = 0.036).

Conclusion: We found higher percentage of survival among adults engaged in sports at moderate-vigorous intensity and with at least four months of previous engagement.  相似文献   

19.
Individuals in five European countries—Finland, France, Germany, Spain, and the United Kingdom (n = 1184)—completed a survey exploring the relationship between organizational dissent and workplace freedom of speech. Results revealed workplace freedom of speech is positively correlated with dissent among the entire sample in France and in Germany. Results in Spain were nonsignificant. In the United Kingdom, there was a negative relationship between workplace freedom of speech and dissent. There was a negative relationship between workplace freedom of speech and articulated dissent and a positive relationship with latent dissent in Finland. Moreover, MANCOVA testing showed nationality to have a significant effect on organizational dissent and workplace freedom of speech. Germans scored the highest on dissent and workplace freedom with Spain scoring the lowest.  相似文献   
20.
The aim of this study was to analyze the effects of resistance training (RT) performed with 1 or 3 sets per exercise on osteosarcopenic obesity (OSO) syndrome parameters in older women. Sixty-two older women (68.0 ± 4.3 years, 26.8 ± 4.4 kg/m2) participated in a 12-week RT program. Participants were randomly assigned into one of the three groups: two training groups that performed either 1 set (G1S, n = 21) or 3 sets (G3S, n = 20) 3 times weekly, or a control group (CG, n = 21). Body composition was assessed by dual X-ray absorptiometry, strength was evaluated by 1 repetition maximum testing. The G3S presented significantly higher strength changes than G1S. The changes for percentage of body fat were higher for G3S compared to G1S. There was no difference in skeletal muscle mass between G3S and G1S, however both training groups displayed greater increases in this outcome compared to CG. There was no effect for bone mineral density. The overall analysis indicated higher (< 0.05) positive changes for G3S than G1S (composed Z-score: G3S = 0.62 ± 0.40; G1S = 0.11 ± 0.48). The results suggest that a 12-week RT period is effective to improve the risk factors of OSO, and that 3 sets induce higher improvements than a single set.  相似文献   
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