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This study examined the long-term effects of the 11+ on physical performance in adolescent male football (soccer) players. Eighty-two 14- to 16-year-old male football players (11+ = 42 players, control = 40 players) participated. Teams were randomised to control (CON) and intervention (INT) groups. INT applied the 11+ injury prevention programme for 30 weeks at least twice a week as a warm-up. CON performed their standard warm-up. Motor performance tests were conducted 1 week prior and 1 week after the competition season. We used magnitude-based inferences and linear mixed-effects models to analyse performance test results. INT showed superior results compared to CON in the vertical jump height 7.5% (95%-CI 4.4%, 10.7%), the Bosco 15-s-jump test 7.2% (95%-CI 2.2%, 12.4%), and the Illinois agility test ?2.6% (95%-CI ?4.1%, ?1.1%). Possibly beneficial effects in favour of INT were found in the 9.1 m sprint test ?3.1% (95%-CI ?6.1%, 0.1%). Possibly harmful effects (i.e. in favour of CON) were observed in the dribbling test 2.8% (95%-CI ?0.8%, 6.4%). The 11+ warm-up programme can improve different performance measures in football players. Coaches might implement additional dribbling drills next to the 11+ to achieve improvements observed in dribbling ability when using a regular warm-up programme.  相似文献   
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Purpose: The aim of this study was to analyze the motivations of non-conventional innovation actors to engage in innovation processes, how their involvement changed the technology and their own social-professional status, and to analyze their role in the diffusion of the innovation.

Design/methodology/approach: We studied the innovation process of drip irrigation in Morocco. We interviewed 35 farmers in two villages, selected to represent a diversity of farms, and observed their drip irrigation systems. We interviewed several local artisans and traders, and intermediaries about their social-professional pathway, using a checklist to understand their motivations and their involvement with drip irrigation.

Findings: We showed how a variety of non-conventional actors became involved in drip irrigation, leading to the progressive creation of an active inter-related socio-technical network involved in the sales, manufacturing, fitting, and use of drip irrigation systems. This network challenged an imported technology promoted by irrigation companies that targeted large-scale farmers, and transformed it into drip irrigation systems adapted to a wide range of situations and farmers, including small-scale farmers. The involvement of these actors led to reciprocal changes in the technology and in the socio-professional status of the intermediaries, hence accelerating the diffusion of the innovation.

Practical implications: Understanding the motivations of non-conventional innovation actors helps comprehend the multiple pathways of innovation processes, and the socio-professional pathways of innovation actors. It is worth considering integrating these actors in state programs and other planned innovation processes, as they are near to field realities and to innovation users, and are able to adapt a technology to local requirements.

Originality/value: The results of this study contribute to the scientific debate about the mutually beneficial alliance of non-conventional actors and technical innovations.  相似文献   

14.
A rugby scrum’s front row must act uniformly to transfer maximal horizontal force and improve performance. This study investigated the muscle activation patterns of lower extremity muscles in front row forwards during live and machine scrums at professional and amateur levels. Electromyography was collected bilaterally on vastus lateralis, rectus femoris and gastrocnemius muscles of 75 male rugby prop players during live and machine scrums. ANOVAs compared muscle reaction time, rate of change in muscle amplitude and muscle amplitude between groups and conditions. Cross-correlation analysis explored muscle synchronicity. There were significantly greater rates of change in each muscle amplitude in professional players than amateur players. Additionally, there was significantly quicker muscle reaction time in all muscles, and greater amplitude in vastus lateralis and gastrocnemius, during the live scrum vs. machine condition. The professional props produced more synchronised muscle activation than amateur players and all players produced more synchronised muscle activation against the scrum machine vs. live scrummage. The results indicate a higher skill proficiency and muscle synchronicity in professional players. While scrum machine training is ideally suited for functional muscle strengthening during practice, to truly simulate the requirements of the scrum, training should incorporate the live situation as much as possible.  相似文献   
15.
The purpose of this research is to study co-authorship and scientific publications of faculty members at Shahed University, located in Iran, during the period of 2000 to 2008. Scientometrics methods were used to evaluate scientific publications. The rate of co-authorship is high (91.27%) in comparison with single authorship (8.73%). Moreover, there is a great number of scientific collaborations among Shahed University faculty members but international collaboration is low. The article provides insight into co-authorship at Shahed University and provides useful information for researchers who are seeking to learn about the collaboration in scientific works by Iranian researchers at the national and international levels.  相似文献   
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Modeling users in information filtering systems is a difficult challenge due to dimensions such as nature, scope, and variability of interests. Numerous machine-learning approaches have been proposed for user modeling in filtering systems. The focus has been primarily on techniques for user model capture and representation, with relatively simple assumptions made about the type of users' interests. Although many studies claim to deal with adaptive techniques and thus they pay heed to the fact that different types of interests must be modeled or even changes in interests have to be captured, few studies have actually focused on the dynamic nature and the variability of user-interests and their impact on the modeling process. A simulation based information filtering environment called SIMSFITER was developed to overcome some of the barriers associated with conducting studies on user-oriented factors that can impact interests. SIMSIFTER implemented a user modeling approach known as reinforcement learning that has proven to be effective in previous filtering studies involving humans. This paper reports on several studies conducted using SIMSIFTER that examined the impact of key dimensions such as type of interests, rate of change of interests and level of user-involvement on modeling accuracy and ultimately on filtering effectiveness.  相似文献   
18.
Bug reports are an essential part of a software project's life cycle since resolving them improves the project's quality. When a new bug report is received, developers usually need to reproduce the bug and perform code review to locate the bug and assign it to be fixed. However, the huge number of bug reports and the increasing size of software projects make this process tedious and time-consuming. To solve this issue, bug localization techniques try to rank all the source files of a project with respect to how likely they are to contain a bug. This process reduces the search space of source files and helps developers to find relevant source files quicker. In this paper, we propose a multi-component bug localization approach that leverages different textual properties of bug reports and source files as well as the relations between previously fixed bug reports and a newly received one. Our approach uses information retrieval, textual matching, stack trace analysis, and multi-label classification to improve the performance of bug localization. We evaluate the performance of the proposed approach on three open source software projects (i.e., AspectJ, SWT, and ZXing) and the results show that it can rank appropriate source files for more than 52% of bugs by recommending only one source file and 78% by recommending ten files. It also improves the MRR and MAP values compared to several existing state-of-the-art bug localization approaches.  相似文献   
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In this study, the hot backward extrusion of Ti–6Al–4V alloy is considered by finite element analysis and experiments. The effects of reduction and initial billet temperature on the force required for extrusion, on the maximum strain produced and on the formation of surface cracks are discussed. The simulation results show that the increase of temperature at high reduction is considerable and that can be reached 150 °C in the billet and punch interface. Moreover, the maximum strain is predicted at the interface of billet and punch. The study shows that the temperature rise and plastic deformation may induce surface cracks.  相似文献   
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