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151.
A field study was conducted in Israel to identify emblematic gestures recognized and used by Hebrew speakers. Studies which have identified the emblematic gestures of particular ethnic or national groups are reviewed and criticized. This study seeks to contribute increased rigor and systematology to the identification of particular groups' emblematic gestures.Twenty-six gestures commonly used in classroom interaction were selected for testing. The instrument used was Schneller's form, “Investigations of Interpersonal Communication in Israel.” Subjects included college students, members of YMCA classes for pensioners, and others. On the instrument, subjects noted their recognition and interpretations of the investigator's encoding intentions, their certainty or interpretation and where they learned each gesture.Whereas previous studies of this nature accepted around 70% interpretive agreement among subjects, this study indicates that at least 90% is a more reliable measure by which to label gestures “emblems.” In addition, correlations were tabulated for the effects of subjects' age, ethnicity, years in Israel, certainty about interpretation, and accuracy of interpretation.The findings of this study were: (a) eight gestures were identified as emblems, and three more gestures identified as possible emblems, (b) slightly negative although insignificant correlations were found between increased age, years in Israel, expressed certainty of interpretation and accuracy of interpretation, and (c) natives and subjects from 20–24 years of age tended to have the highest rates of expressed certainty of interpretation as well as accuracy of interpretation.The findings are compared with those of three other studies of Jews' gesturing and differences between the studies are considered. Recommendations include continuing such studies and comparing the results of related projects in order to form a comprehensive picture of particular groups of people.Limitations are discussed. These include: (a) a less than representative sample, (b) lack of a consistent conversational context, (c) potential for distortion in the decoding process, (d) the lack of a unified gesture labeling system, and (e) the possibility of cultural or researcher bias.  相似文献   
152.
All live systems acquire and use knowledge to ensure appropriate efficiency in the mutual intercourse with the surrounding environment. Knowledge can be communicated only when the subject's internal model of the object of reality is objectified by means of a certain set of physical signs. Such an externalized model, a communicate, is to be accepted, adequately understood and evaluated by other relevant live systems. The information value of a communicate is therefore a function not only of the communicate itself but of the needs, aims, expectations and possibilities of relevant live systems as well. The information value of the same communicate can vary within a set of those systems. The determination of regularities in the relations between the information value of communicates, their content similarity and distinctive features of live systems producing and using them is a problem for experimental and empirical studies.  相似文献   
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This paper examines Brazil’s Sector Funds, an emerging research and development policy that seeks to increase public-private research collaboration. The first section sets the context of the ‘policy problem’. The second section discusses the policy’s implementation, and discusses its likely implications for Brazil and beyond.  相似文献   
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157.
Electrosprays are a powerful technique to generate charged micro/nanodroplets. In the last century, the technique has been extensively studied, developed, and recognized with a shared Nobel price in Chemistry in 2002 for its wide spread application in mass spectrometry. However, nowadays techniques based on microfluidic devices are competing to be the next generation in atomization techniques. Therefore, an interesting development would be to integrate the electrospray technique into a microfluidic liquid-liquid device. Several works in the literature have attempted to build a microfluidic electrospray with disputable results. The main problem for its integration is the lack of knowledge of the working parameters of the liquid-liquid electrospray. The “submerged electrosprays” share similar properties as their counterparts in air. However, in the microfluidic generation of micro/nanodroplets, the liquid-liquid interfaces are normally stabilized with surface active agents, which might have critical effects on the electrospray behavior. In this work, we review the main properties of the submerged electrosprays in liquid baths with no surfactant, and we methodically study the behavior of the system for increasing surfactant concentrations. The different regimes found are then analyzed and compared with both classical and more recent experimental, theoretical and numerical studies. A very rich phenomenology is found when the surface tension is allowed to vary in the system. More concretely, the lower states of electrification achieved with the reduced surface tension regimes might be of interest in biological or biomedical applications in which excessive electrification can be hazardous for the encapsulated entities.  相似文献   
158.
Abstract The aim of this study was to examine the effect of positioning on the correctness of decision making of top-class referees and assistant referees during international games. Match analyses were carried out during the Fédération Internationale de Football Association (FIFA) Confederations Cup 2009 and 380 foul play incidents and 165 offside situations were examined. The error percentage for the referees when indicating the incidents averaged 14%. The lowest error percentage occurred in the central area of the field, where the collaboration of the assistant referee is limited, and was achieved when indicating the incidents from a distance of 11-15?m, whereas this percentage peaked (23%) in the last 15-min match period. The error rate for the assistant referees was 13%. Distance of the assistant referee to the offside line did not have an impact on the quality of the offside decision. The risk of making incorrect decisions was reduced when the assistant referees viewed the offside situations from an angle between 46 and 60°. Incorrect offside decisions occurred twice as often in the second as in the first half of the games. Perceptual-cognitive training sessions specific to the requirements of the game should be implemented in the weekly schedule of football officials to reduce the overall error rate.  相似文献   
159.
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
160.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.  相似文献   
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