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901.
ABSTRACTOnline learning as a concept and as a keyword has consistently been a focus of education research for over two decades. In this paper, we present results from a systematic literature review for the definitions of online learning because the concept of online learning, though often defined, has a range of meanings attached to it. Authors and scholars use the term to mean very distinct, if not contradictory concepts. We conducted systematic literature for over the last 30 years (1988 to 2018) to investigate the number and content of definitions of online learning. We collected 46 definitions from 37 resources and conducted a content analysis on these sets of definitions. Content analysis of the collected definitions led to an understanding of the core elements for defining online learning, the confusion surrounding the terms and the synonyms used for online learning. An evolution of the definition of the concept of online learning was also mapped to the evolution of technology in the last three decades. 相似文献
902.
Patrick Löffler Marcela Pozas Alexander Kauertz 《International Journal of Science Education》2013,35(16):1935-1956
ABSTRACTIn science education, context-based learning is mostly based on problem-oriented tasks [Gilbert, J. K. (2006). On the nature of “context” in chemical education. International Journal of Science Education, 28(9), 957–976]. Therefore, a relevant question is, how do students integrate the information given in the task into their problem-solving process? The basic assumption is that there is a transition from the situation described in the task to a science model needed to solve the problem [Mestre, J. (2002). Probing adults’ conceptual understanding and transfer of learning via problem posing. Journal of Applied Developmental Psychology, 23(1), 9–50]. The transition needs to be described by parameters of the situation, the science model and the transition process itself. This investigation focuses on the influence of these three elements on the problem-solving process to understand variations in performance [Bennett, J., Lubben, F., & Hogarth, S. (2007). Bringing science to life: A synthesis of the research evidence on the effects of context-based and STS approaches to science teaching. Science Education, 91(3), 347–370]) and the interaction with interest. Despite the large body of research on the mutual influence of context-based problem-solving and interest, research attempting to examine their interplay regarding performance is still lacking. We conducted a hierarchical regression analysis with 178 participants from German high-track schools to investigate three parameters with regard to their influence on affective variables and successful problem-solving: contextualisation of the situation described in the task; the complexity of the scientific model underlying the task; and transparency, which assesses whether and how the learner can identify this model [Löffler, P., & Kauertz, A. (2015). Modellanwendung in kontextualisierten Problemlöseaufgaben [Applying models in contextualised problem solving tasks]. In S. Bernholt (Ed.), Heterogenität und Diversität - Vielfalt der Voraussetzungen im naturwissenschaftlichen Unterricht (Vol. 35, pp. 648–650). Kiel: IPN; Durik, A., & Harackiewicz, J. (2007). Different strokes for different folks: How individual interest moderates the effects of situational factors on task interest. Journal of Educational Psychology, 99(3), 597–610)]. Our findings suggest that these parameters have different effects on how interest is triggered and maintained. Aspects of transparency exhibit small effects on successful problem-solving processes. The results support the assumption that the transition process is the main aspect of context-based problem-solving and can therefore be operationalised as the use of elements of the scientific model in students’ statements. Surprisingly, the usage of such elements cannot be sufficiently explained by pre-knowledge or cognitive abilities. 相似文献
903.
High school students’ difficulties in understanding osmosis 总被引:1,自引:0,他引:1
Yael Friedler Ruth Amir Pinchas Tamir 《International Journal of Science Education》2013,35(5):541-551
Preconceptions and misconceptions of 500 secondary students in years 9‐12 regarding osmosis were studied through the use of five different kinds of instruments: prior learning inventory, self‐report knowledge inventory, true/false test, definitions and clinical interviews. Some of the major findings were: (1) The most frequent explanation offered to osmosis is ‘a desire or drive towards equalizing concentrations’. (2) Hardly any student uses the concept ‘water concentration’. (3) Most students fail to realize that in dynamic equilibrium water molecules keep moving. (4) Students have special difficulty in understanding osmotic relations in plants. (5) Many students have difficulty in grasping solute‐solvent and concentration‐quantity relations. (6) Students often perform laboratory experiments without really understanding the underlying principles. Practical and theoretical implications are discussed. 相似文献
904.
Deirdre Dlugonski Aaron P. Wood Katrina D. DuBose Patrick Rider Alexander M. Schoemann 《Measurement in physical education and exercise science》2013,17(3):272-279
ABSTRACTIntroduction: This study examined the concurrent validity and inter-pair reliability of the proximity detection function on Bluetooth-enabled accelerometers across manufacturer-specified ranges. If valid, this method could be used for objectively measuring shared physical activity participation. Method: Thirty-six dyads aged 21.6 (2.1) years wore two sets of Bluetooth-enabled accelerometers initialized as beacons and receivers to compare accelerometer-measured proximity detection to direct observation under 11 different controlled and free-living conditions. Results: The proportion of minutes in which proximity was detected differed across conditions (p < .001), with the highest proportions in the controlled conditions (.77–1.0). Among the free-living conditions, the different room (.73 ± .20) condition had the highest proximity detection proportions. There were no differences in the proximity detection across accelerometer pairs (p = .265). Conclusion: Proximity detection with Bluetooth-enabled accelerometers was reliable and had the highest detection rates under the controlled treadmill walking conditions. Despite limitations, using Bluetooth-enabled accelerometers is a promising approach for measuring shared physical activity. 相似文献
905.
A continuously waxed ski has been developed that releases a thin film of lubricant under the base of a ski. This replicates the melt water layer observed in snow skis which is caused by frictional and solar heating. The system is particularly effective on artificial (dry) slopes where skiers slide on plastic bristles rather than snow. Speeds comparable to those achieved on snow are achieved using this system and this improves the experience for the skier. Speed enhancements on plastic slopes of up to 50?% have been achieved using solutions of polyethylene glycol in water. There is speed enhancement of approximately 9?% on artificial snow and 2?% on fresh alpine snow. The latter value is highly significant as it can be the difference between winning a medal in ski competitions and finishing outside the top ten. In addition to the quantitative data, qualitative athlete perceptions were also recorded and show that a feel like snow can be achieved on artificial surfaces. Because the lubrication system is attached to the ski, it allows personal performance enhancement irrespective of a water misting system being in operation or not. The design complies with the equipment regulations of the skiing??s international governing body so it can be used in competition. 相似文献
906.
This paper examines the relationship between a firm's strategic framework and business environment and the probability of becoming the target of “copying”, differentiated into (i) unauthorized reproduction of its technological product elements or insignia, and (ii) patent and trademark infringement. Based on bivariate and multivariate analyses of survey data, we show patterns of the links between being (legally or illegally) imitated and IP protection (e.g., defensive publishing), general strategy (e.g., selling products abroad or off-shoring R&D activities) and organizational factors (e.g., firm size). Management implications for successful strategies against the different types of being copied are derived. 相似文献
907.
Abstract Several recent investigations showed that the best marathon time of an individual athlete is also a strong predictor variable for the race time in a 100-km ultra-marathon. We investigated similarities and differences in anthropometry and training characteristics between 166 100-km ultra-marathoners and 126 marathoners in recreational male athletes. The association of anthropometric variables and training characteristics with race time was assessed by using bi- and multi-variate analysis. Regarding anthropometry, the marathoners had a significantly lower calf circumference (P?0.05) and a significantly thicker skinfold at pectoral (P?0.01), axilla (P?0.05), and suprailiacal sites (P?0.05) compared to the ultra-marathoners. Considering training characteristics, the marathoners completed significantly fewer hours (P?0.001) and significantly fewer kilometres (P?0.001) during the week, but they were running significantly faster during training (P?0.001). The multi-variate analysis showed that age (P?0.0001), body mass (P?=?0.011), and percent body fat (P?=?0.019) were positively and weekly running kilometres (P?0.0001) were negatively related to 100-km race times in the ultra-marathoners. In the marathoners, percent body fat (P?=?0.002) was positively and speed in running training (P?0.0001) was negatively associated with marathon race times. In conclusion, these data suggest that performance in both marathoners and 100-km ultra-marathoners is inversely related to body fat. Moreover, marathoners rely more on speed in running during training whereas ultra-marathoners rely on volume in running training. 相似文献
908.
Weitkunat T Knechtle B Knechtle P Rüst CA Rosemann T 《Journal of sports sciences》2012,30(10):1003-1013
Body mass changes during ultra-endurance performances have been described for running, cycling and for swimming in a heated pool. The present field study of 20 male and 11 female open-water swimmers investigated the changes in body composition and hydration status during an ultra-endurance event. Body mass, both estimated fat mass and skeletal muscle mass, haematocrit, plasma sodium concentration ([Na+]) and urine specific gravity were determined. Energy intake, energy expenditure and fluid intake were estimated. Males experienced significant reductions in body mass (-0.5 %) and skeletal muscle mass (-1.1 %) (P < 0.05) during the race compared to females who showed no significant changes with regard to these variables (P > 0.05). Changes in percent body fat, fat mass, and fat-free mass were heterogeneous and did not reach statistical significance (P > 0.05) between gender groups. Fluid intake relative to plasma volume was higher in females than in males during the ultra-endurance event. Compared to males, females' average increase in haematocrit was 3.3 percentage points (pp) higher, urine specific gravity decrease 0.1 pp smaller, and plasma [Na+] 1.3 pp higher. The observed patterns of fluid intake, changes in plasma volume, urine specific gravity, and plasma [Na+] suggest that, particularly in females, a combination of fluid shift from blood vessels to interstitial tissue, facilitated by skeletal muscle damage, as well as exercise-associated hyponatremia had occurred. To summarise, changes in body composition and hydration status are different in male compared to female open-water ultra-endurance swimmers. 相似文献
909.
Robin Alexander 《Literacy》2010,44(3):103-111
Taking the 2009 UKLA conference theme of “making connections and building literate communities” and recalling Hoggart's plea for literacy to be critically and morally engaged rather than merely functional, this paper calls for a reassessment of the pursuit of literacy in schools so as to connect the language of learning with the language of democratic participation. Given what we know about the way classroom talk mediates both learning and culture, the paper takes such talk as its focus, comparing the author's principles of dialogic teaching with Resnick's criteria for accountable talk. The paper then contrasts these idealised versions of the discourse of pedagogy with the public discourses of power, noting the prevalence of four discourse types – derision, dichotomy, myth and meaninglessness – through which, in pursuit of political goals, governments rewrite history, simplify the problematic, dignify the mundane and marginalise unpalatable evidence. This prompts an addition, in the interests of meaningful citizenship as well as effective learning, to Resnick's criteria of accountability to the learning community, standards of reasoning and knowledge: accountability to language itself. 相似文献
910.