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951.
The purpose of professional education programs is to prepare aspiring professionals for the challenges of practice within a particular profession. These programs typically seek to ensure the acquisition of necessary knowledge and skills, as well as providing opportunities for their application. While not denying the importance of knowledge and skills, this paper reconfigures professional education as a process of becoming. Learning to become a professional involves not only what we know and can do, but also who we are (becoming). It involves integration of knowing, acting, and being in the form of professional ways of being that unfold over time. When a professional education program focuses on the acquisition and application of knowledge and skills, it falls short of facilitating their integration into professional ways of being. In addition, through such a focus on epistemology (or theory of knowing), ontology (or theory of being) is overlooked. This paper explores what it means to develop professional ways of being where the focus is becoming, not simply knowing as an end in itself.  相似文献   
952.
This paper explores 30 students' views on the purposes for studying US history. Twelve students were 5th graders, 12 were 8th graders, and six were high school students. Responses were drawn from detailed interview protocol data compiled over three years in the context of a larger research programme that extensively studied the teaching and learning practices in five American history classrooms, two at 5th grade, two at 8th grade, and one at the high school level. Two questions from the protocol frame this exploration:'Why do you think they teach you American history in school?' and 'How might learning American history help you in your life away from school?'. Responses indicated that (a )all the students were able to construct some answer to the questions; (b ) rationales for learning history varied considerably by age, interest and ethnic background, but versions of the Santayanan rationale and utilitarian responses were most common; (c ) students seemed initially puzzled by the questions as though they had never considered them before; and (d ) students appeared to hold a 'stabilized', consensus view of history, meaning that they thought of history as a collection of putative facts and that their task was to learn them. Implications are considered against the backdrop of teaching and learning American history and the current history curriculum.  相似文献   
953.
Thinking historically   总被引:1,自引:1,他引:0  
  相似文献   
954.
955.
To assess the possible effects of mechanical loading on the conservation of historical wooden musical instruments, a research project was carried out on the violin Guarneri “del Gesù” (1743), known as the “Cannone”. This paper refers to the results obtained by studying the deformations to which a violin is subjected after being tuned, with special attention to the viscous and mechano-sorptive behaviour (as in a concert environment for example). The amount of viscoelastic creep was quantified under normal tuning conditions, and the mechano-sorptive creep was quantified using a dead mass resulting in 55% of the elastic deformation obtained after tuning. The viscoelastic and mechano-sorptive deformations were clearly observed. These deformations were completely recovered once the violin was unloaded, demonstrating that this violin structure is appropriately dimensioned for the applied stresses.  相似文献   
956.
Three‐dimensional (3‐D) high‐speed cinematographic techniques were used to record topspin and backspin forehand approach shots hit down‐the‐line by high‐performance players. The direct linear transformation (DLT) technique was used in the 3‐D space reconstruction from 2‐D images recorded via laterally placed phase‐locked cameras operating at 200 Hz. A Mann‐Whitney U‐test was calculated for the different aspects of the topspin and backspin shots to test for significance (P<0.05).

A significant difference was recorded between topspin and backspin shots in the angle of the racket at the completion of the backswing. The racket was taken 0.48 rad past a line drawn perpendicular to the back fence for topspin trials, but only rotated 0.86 rad from a line parallel to the net in the backspin shot. Maximum racket velocities occurred prior to impact and were significantly higher in topspin (26.5 m s‐1) compared to backspin (16.6 m s‐1) trials. This resulted in the topspin trials recording a significantly higher ball velocity compared to backspin trials (27.6 m s‐1 vs 21.7 m s‐1). Pre‐impact racket trajectories revealed that in topspin shots the racket moved on an upward path of 0.48 rad while in backspin shots it moved down at an angle of 0.34 rad. In the topspin trials impact occurred significantly further forward of the front foot than in backspin shots (0.26 m vs 0.05 m) while the angle of the racket was the same for both strokes (0.14 rad behind a line parallel to the net). The mean angle of the racket‐face at impact was inclined backwards by 0.11 rad for backspin strokes and rotated forward by 0.13 rad for topspin strokes. Angles of incidence and reflection of the impact between the ball and the court showed that backspin trials had larger angles of incidence and reflection than topspin strokes.  相似文献   
957.
Three‐dimensional (3‐D) high‐speed cinematography was used to record the penalty throw in water polo by six elite male (M) and six elite female (F) players. The direct linear transformation technique (DLT) was used in the 3‐D space reconstruction from 2‐D images recorded via laterally placed phase‐locked cameras operating at 200 Hz. Five of the twelve subjects lifted the ball from underneath at the start of the throw whilst the remaining subjects opted for a rotation lift. As the ball was brought behind the head the females used very little hip and shoulder rotation compared to the male players so that four of the six female subjects were square on to the target at the rear point. At the completion of the backswing the wrist was flexed to a similar angle (M‐162°; F‐158°); the elbow angle showed significantly greater flexion for females (85°) than males (107°).

During the forward swing, from rear point to release, the wrist joint of the female players flexed from a rear point angle of 158° to 148° at release. The wrist movement for male subjects was different from the females in that it flexed from 162° to 147°, 0.10 s prior to release and then extended to 159° at palmar release before again flexing to 156° at release. The amount of elbow extension during the forward swing was 48° for both groups; however, the females actually released the ball with the forearm vertical (89°) compared to the male forearm angle of 78°. Maximum angular velocity of the wrist and elbow occurred at release for 9 of the 12 subjects. Both the wrist and elbow joints (F‐148°; M‐156° at wrist and F‐126°; M‐148° at elbow) demonstrated greater flexion at release in female subjects, compared with males. Maximum linear endpoint velocities for the forearm and hand segments occurred at ball release resulting in mean ball velocities of 19.1 m s ‐1 and 14.7 m s‐ 1 for male and female subjects respectively.  相似文献   
958.
959.
Abstract

We assessed the attentional demands of drawing and passing in rugby league players and investigated the effects of single-task and dual-task training on the acquisition, retention, and transfer of skill in these athletes. In Study 1, high-skilled and lesser-skilled rugby league players performed a standardized 2-on-1 drill under single-task (primary skill in isolation) and dual-task (primary skill while performing a secondary verbal tone recognition task) conditions. No differences were detected in primary task performance between groups, although the performance of the high-skilled players was more resistant to skill decrement under dual-task conditions. In Study 2, high-performance rugby league players were randomly allocated to either a single-task or dual-task training group. Each group underwent 8 weeks of training between the pre- and post-test sessions. While the mean improvement for draw and pass proficiency under dual-task conditions in the dual-task training group was greater than in the single-task training group (10.0% vs. 2.3%), the differences, while providing a moderate effect size (d = 0.57), were not statistically significant. These results suggest that the attentional demands of drawing and passing are reduced in high-skilled rugby league players compared with their lesser-skilled counterparts. In addition, compared with single-task training, dual-task training appears to improve the ability to perform dual-task draw and pass tasks (possibly through an improvement in time-sharing skills). Further studies are required to verify the efficacy of dual-task training as a training stimulus.  相似文献   
960.
Abstract

A study of the effect of fatigue on the mechanical characteristics of running during a 10,000 meter race was undertaken using high speed cinematography and a computer analysis technique. Eight highly skilled male subjects were filmed at four intervals throughout the event. An analysis of variance for trends was conducted for each of the dependent variables indicating the adjustments made by the runners that accompanied fatigue over the four stages of the event. Runners countered fatigue by changing sections of their total gait pattern (stride length, stride rate, segmental body positions) and reducing running velocity. Toward the end of the race the runners became less competent in the positioning of the foot and leg at foot-strike, which increased the potential for a retarding effect. A more extended lower limb increased the energy requirements of the recovery phase during the latter stages of the race. Fatigue caused these highly skilled runners to systematically alter their technique throughout the race. These adjustments, however, were not excessive.  相似文献   
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