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Abstract

A large body of evidence now shows that higher protein intakes (2–3 times the protein Recommended Dietary Allowance (RDA) of 0.8 g/kg/d) during periods of energy restriction can enhance fat-free mass (FFM) preservation, particularly when combined with exercise. The mechanisms underpinning the FFM-sparing effect of higher protein diets remain to be fully elucidated but may relate to the maintenance of the anabolic sensitivity of skeletal muscle to protein ingestion. From a practical point of view, athletes aiming to reduce fat mass and preserve FFM should be advised to consume protein intakes in the range of ~1.8–2.7 g kg?1 d?1 (or ~2.3–3.1 g kg?1 FFM) in combination with a moderate energy deficit (?500 kcal) and the performance of some form of resistance exercise. The target level of protein intake within this recommended range requires consideration of a number of case-specific factors including the athlete's body composition, habitual protein intake and broader nutrition goals. Athletes should focus on consuming high-quality protein sources, aiming to consume protein feedings evenly spaced throughout the day. Post-exercise consumption of 0.25–0.3 g protein meal?1 from protein sources with high leucine content and rapid digestion kinetics (i.e. whey protein) is recommended to optimise exercise-induced muscle protein synthesis. When protein is consumed as part of a mixed macronutrient meal and/or before bed slightly higher protein doses may be optimal.  相似文献   
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Multi-document discourse parsing aims to automatically identify the relations among textual spans from different texts on the same topic. Recently, with the growing amount of information and the emergence of new technologies that deal with many sources of information, more precise and efficient parsing techniques are required. The most relevant theory to multi-document relationship, Cross-document Structure Theory (CST), has been used for parsing purposes before, though the results had not been satisfactory. CST has received many critics because of its subjectivity, which may lead to low annotation agreement and, consequently, to poor parsing performance. In this work, we propose a refinement of the original CST, which consists in (i) formalizing the relationship definitions, (ii) pruning and combining some relations based on their meaning, and (iii) organizing the relations in a hierarchical structure. The hypothesis for this refinement is that it will lead to better agreement in the annotation and consequently to better parsing results. For this aim, it was built an annotated corpus according to this refinement and it was observed an improvement in the annotation agreement. Based on this corpus, a parser was developed using machine learning techniques and hand-crafted rules. Specifically, hierarchical techniques were used to capture the hierarchical organization of the relations according to the proposed refinement of CST. These two approaches were used to identify the relations among texts spans and to generate multi-document annotation structure. Results outperformed other CST parsers, showing the adequacy of the proposed refinement in the theory.  相似文献   
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This paper explores the prospective transition of immigrant and native students in France from lower to upper secondary school. Because they are more likely to be tracked to less prestigious (vocational) tracks, immigrant and immigrant‐origin students are significantly disadvantaged at this key academic stage in comparison with the children of native families. Primary and secondary sources of educational disadvantage are explored to explain this phenomenon. Primary effects appear to account for the entire initial disadvantage, while secondary effects could have a positive impact for immigrant‐origin students. Nonetheless, immigrant families appear to be more conservative than native families and may need stronger evidence that their children will succeed in upper secondary school.  相似文献   
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This paper discusses implications of the convergence of legal and organizational issues in the context of developing and implementing digital government projects in large urban settings. By the convergence of legal and organizational issues we refer to two important aspects of urban government: (1) the close relationship between legal/policy structures and the way government is organized and functions, and (2) the way the legal/policy elements interact with organizational dynamics and work cultures to influence digital government projects (and government activities generally). It is our contention that convergence in the organizational and legal/policy context is a powerful determinant of how these projects develop and how likely they are to succeed. Therefore the understanding of this convergence and related dynamics is critically important to planning and designing both policy to promote digital government and particular digital government projects themselves. Illustrations of this convergence and its consequences are presented. They are based on research involving two digital government projects in urban settings: development of a management information system for homeless shelter administration and a developing a system for sharing information among New York City agencies.  相似文献   
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This qualitative multiple-comparative case study investigates (1) The reported experiences and impressions of four pre-service teachers (PTs) on practicum placement in four different classrooms (grades 1–9) where a new Steps to Inquiry (SI) framework was being utilized to support students conducting open inquiry; (2) The relative dispositions of the PTs toward conducting open inquiry, as indicated by their core conceptions regarding science, the purpose of education, effective teaching, and the capacity of students. Findings indicate that (1) although there were differences in the experiences of the four PTs, all four had an opportunity to observe and/or facilitate students conducting open inquiry with the SI framework, and after the practicum, all of them reported that they would like to include open inquiry in their own classrooms in the future; (2) one PT already possessed core conceptions indicative of a favorable disposition toward open inquiry before the placement; another altered her core conceptions substantially toward a favorable disposition during the placement; a third altered her conceptions regarding the capacity of students; and one PT maintained core conceptions indicative of a disposition that was not favorable to open inquiry despite the pronouncements that she would like to conduct open inquiry with students in their own future classroom. Possible reasons for the differences in the responses of the four pre-services teachers to the practicum placement are discussed.  相似文献   
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This research identifies main feedback dynamics associated with social processes necessary to make sense of ambiguous project goals, typical of large digital government projects. The study reports on findings from a case analysis using participatory approaches in system dynamics, based on a digital government project integrating information systems of New York's criminal justice agencies. Findings stress the importance of visuals in the sensemaking process that results from the interaction of technical and social outcomes produced through identifying and continuously re-interpreting main project issues and goals. Project analyses suggest that requisite elements of successfully managing this type of project include 1) facilitation that enables diversity of ideas, 2) shared visuals and re-presentations of participants' efforts to work on the issues, and 3) iterative social construction of objectives, progress, and valid processes for doing the work; each of these plays a role in three different feedback processes sustaining (or undermining) the group engagement needed to yield successful integrative work. The study contributes to the literature in digital government by introducing the lenses of people-centered project management processes, an emerging approach in project management, to underscore the role of social processes in technical projects.  相似文献   
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The minimal realization theory for input–output maps that arise from finite- dimensional, continuous time, bilinear systems is discussed. It is shown that an observed bilinear system (i.e. a bilinear system together with an observation functional, but without a fixed initial state) is completely determined by its input–output correspondence, i.e. its multivalued input–output map. A precise formulation and proof of the result are given that continuous canonical forms for bilinear systems do not exist. This is done by adapting to the bilinear case an idea due to Hazewinkel and Kalman for the case of linear systems. In addition, the proof presented here has the advantage of not involving any algebraic geometry, which makes it considerably simpler than the original proof of the linear systems result.  相似文献   
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