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141.
Aging population has increased a global concern to keep seniors active and healthy. Civic participation, in particular, has been highlighted for its social and community benefits and its impact on elders’ health and well-being. To date, however, most studies have explored volunteering; other types of civic activities, such as political participation, are largely overlooked. This study analyzes the relationship between older people’s active involvement in political organizations, generativity, and hedonic and eudaimonic well-being. We selected two samples of Spanish older people: a sample of elders actively involved in political organizations (n = 97) and a comparison group (n = 85). Measures of generative concern, hedonic well-being, and eudaimonic well-being were applied. Results showed that politically active elders obtained higher scores on generative concern than comparison group individuals. Furthermore, generative concern predicted higher scores on both eudaimonic and hedonic well-being. However, active involvement in political organizations was not related to higher levels of well-being in the multivariate analyses. Translating generative concerns into effective behaviors, for instance political activities, may imply sacrifices and efforts, such that higher levels of well-being do not necessarily result from these activities. Thus, results from this study call into question the positive effect of civic participation on elders’ well-being, showing that this may not be necessarily the case for those who are actively involved in political organizations. Future research may build on these results to compare the differential effect of different kinds of generative activities on older people’s well-being.  相似文献   
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SEAD method estimates the direction-of-arrival angles on an uniformly linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.  相似文献   
144.
This study aimed to assess the effects of post-activation potentiation in the strength related variables of a kick start. Thirteen competitive swimmers performed three kick starts after a standardized warm up (denoted USUAL) and another after inducing post-activation through five isotonic repetitions on an eccentric flywheel (denoted PAP). A T-test was used to quantify differences between USUAL and PAP warm up. The best trial of each subject achieved by natural conditions (denoted PEAK) was compared with data obtained after PAP. An instrumented starting block with independent triaxial force plates, collected the strength variables related with the impulse at take off. Improvements in the vertical components of force were observed after PAP compared with USUAL, meanwhile no differences were detected on the horizontal components of it. The velocity at take off was higher after PAP compared with USUAL (4.32 ± 0.88 vs 3.93 ± 0.60 m*s-1; p = 0.02). No differences in force or velocity were detected comparing PAP with PEAK (4.13 ± 0.62 m*s-1, p = 0.11). The PAP warm-up increased vertical force and it was transferred to a higher resultant velocity at take-off. This improvement would equal the best result possible obtained in natural conditions after some trials.  相似文献   
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146.
This study explores an activist approach for co-creating a prototype pedagogical model of sport for working with boys from socially vulnerable backgrounds. This paper addresses the key features that emerged when we identified what facilitated and hindered the boys’ engagement in sport. This study was an activist research project that was conducted between July 2013 and December 2013 in a soccer program in a socially and economically disadvantaged neighborhood in Brazil. The lead author, supervised by the second author, worked with a soccer class of 17 boys between ages 13 and 15, 4 coaches, a pedagogical coordinator and a social worker. Multiple sources of data were collected, including 38 field journal/observations and audio records of: 18 youth work sessions, 16 coaches’ work sessions and 3 combined coaches and youth work sessions. In addition, the first and second author had 36 90-minute debriefing and planning sessions. By using an activist approach, three features were identified as being essential: an ethic of care, an attentiveness to the community and a community of sport. Findings suggest that it is possible to use sport as a cultural asset to benefit youth from socially vulnerable backgrounds by offering them a place where they can feel protected and dream about possible futures.  相似文献   
147.
The early history of the Jewish and Muslim communities living under Christian rule in the Ebro Valleys tends to be overlooked in favour of the source-rich thirteenth and fourteenth centuries. However, the nature and organisation of these groups should not be taken as a constant, as they underwent a significant transformation over the course of the twelfth century. Through the case study of Tudela, this article proposes to re-examine the dynamics of administration and judicial practice that developed in the immediate aftermath of the Navarro-Aragonese conquest. This town has a rich corpus of charters that allows us to contrast the administrative layout enshrined in the franchise charters known as fueros with the legal practice reflected in some particular bilingual interlineated purchase-sale contracts. A comparison of both sets of documents emphasises the use of the fuero in inter-communal negotiation, both in framing encounters and in guaranteeing each group's autonomy, during a key period in the gestation of Jewish and Muslim administrative and judicial practices under Christian rule.

Abbreviations: DAr = Mercedes García-Arenal, “Documentos árabes de Tudela Y Tarazona”, Al-Qan?ara: Revista de Estudios Árabes 3 (1982): 27–72; FdN = Luis Javier Fortún Pérez de Ciriza, “Colección de ‘fueros menores’ de Navarra y otros privilegios locales (I)”, Príncipe de Viana 165 (1982): 273–348  相似文献   
148.
The aim of this study was to investigate the effects of different types of practice on learning the o soto gari, focusing on the kuzushi (unbalancing the opponent). A total of 64 children (mean age 9.19 ± 1.41 years) were assigned to one of four groups: (1) static traditional practice, i.e., uchikomi – repetition of the moving pattern that characterises the technique up to the point of throwing; (2) in motion traditional practice – uchikomi with the tori (player executing the technique) moving/walking; (3) whole practice with pre-kuzushi – full technique with a preparatory component for kuzushi; (4) progressive parts practice with pre-kuzushi – progressively introducing kuzushi, tsukuri (set-up to execute the technique) and kake (final part of the technique; projection) with pre-kuzushi. Pre-test, acquisition, post-test and retention test were carried out. Movements were video recorded and analysed regarding three aspects: global technique of the tori, occurrence of a movement pattern performed by the tori to unbalance the uke (player receiving the “attack”), and occurrence of actual unbalance (kuzushi). Results showed no significant differences between-groups. However, different within-groups improvements suggest that using a uchikomi with pre-kuzushi can help learners deal with the motor actions of pulling and pushing in order to unbalance the opponent.  相似文献   
149.
ABSTRACT

Previous studies have been limited to describe asymmetries during pedalling and suggest possible repercussion on performance and/or injury risks. However, few studies have presented strategies to mitigate asymmetries. The purpose of this study was to assess the effectiveness of a pedalling retraining intervention to reduce bilateral pedal force asymmetries. Twenty cyclists were assessed and 10 enrolled in a pedalling retraining method receiving visual and verbal feedback of pedal forces. The asymmetry index was computed for comparison of bilateral peak pedal forces and used during retraining (12 trials at 70% of peak power). Significantly larger asymmetry was observed for asymmetrical cyclists at the first three trials (P < 0.01 and ES = 1.39), which was reduced when post-retraining was compared to measures from symmetrical cyclists (P = 0.69 and ES = 0.18). Cyclists with larger asymmetry (>20%) in bilateral pedal forces reduce their asymmetries using sessions of pedalling retraining and achieve asymmetry indices similar to symmetrical cyclists.  相似文献   
150.
The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test-retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h(-1) was increased by 1.2 km · h(-1) every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO(2max) (v-VO(2max)). Peak running velocity in Carminatti's test was strongly correlated with v-VO(2max) (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = -0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.  相似文献   
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