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51.
ABSTRACT

The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R2) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions.  相似文献   
52.
To cope with ambiguous and/or underspecified queries, search result diversification (SRD) is a key technique that has attracted a lot of attention. This paper focuses on implicit SRD, where the subtopics underlying a query are unknown. Many existing methods appeal to the greedy strategy for generating diversified results. A common practice is using a heuristic criterion for making the locally optimal choice at each round. As a result, it is difficult to know whether the failures are caused by the optimization criterion or the setting of parameters. Different from previous studies, we formulate implicit SRD as a process of selecting and ranking k exemplar documents through integer linear programming (ILP). The key idea is that: for a specific query, we expect to maximize the overall relevance of the k exemplar documents. Meanwhile, we wish to maximize the representativeness of the selected exemplar documents with respect to the non-selected documents. Intuitively, if the selected exemplar documents concisely represent the entire set of documents, the novelty and diversity will naturally arise. Moreover, we propose two approaches ILP4ID (Integer Linear Programming for Implicit SRD) and AP4ID (Affinity Propagation for Implicit SRD) for solving the proposed formulation of implicit SRD. In particular, ILP4ID appeals to the strategy of bound-and-branch and is able to obtain the optimal solution. AP4ID being an approximate method transforms the target problem as a maximum-a-posteriori inference problem, and the message passing algorithm is adopted to find the solution. Furthermore, we investigate the differences and connections between the proposed models and prior models by casting them as different variants of the cluster-based paradigm for implicit SRD. To validate the effectiveness and efficiency of the proposed approaches, we conduct a series of experiments on four benchmark TREC diversity collections. The experimental results demonstrate that: (1) The proposed methods, especially ILP4ID, can achieve substantially improved performance over the state-of-the-art unsupervised methods for implicit SRD. (2) The initial runs, the number of input documents, query types, the ways of computing document similarity, the pre-defined cluster number and the optimization algorithm significantly affect the performance of diversification models. Careful examinations of these factors are highly recommended in the development of implicit SRD methods. Based on the in-depth study of different types of methods for implicit SRD, we provide additional insight into the cluster-based paradigm for implicit SRD. In particular, how the methods relying on greedy strategies impact the performance of implicit SRD, and how a particular diversification model should be fine-tuned.  相似文献   
53.
This article presents the first segment of a qualitative study that explores the feasibility of integrating traditional arts in Philippine art and design education. The views of educators on traditional arts were sought to provide an impetus for the study and a springboard for discussion regarding the relevance of traditional Filipino arts in a predominantly Westernised educational system. The educators’ views and opinions on the central question, ‘Why and how should the study of traditional Filipino arts be integrated in the art and design programme?’ will be used to guide a trial integration of the learning of traditional arts in tertiary art and design classes. They will form part of the multiple perspectives that will be gathered from various sectors throughout the course of research. This phenomenological study, on the whole, seeks to uncover the potentials of traditional arts as a rich resource for learning, particularly for students of art and design.  相似文献   
54.
Recent studies indicate that the majority of school psychologists’ time continues to be dedicated to SPED related activities. Despite ongoing calls for school psychologists to expand their roles, why many practitioners do not deliver more comprehensive services is not well understood. This qualitative study investigated facilitators of and barriers to comprehensive and integrated services using the National Association of School Psychologists Model for Comprehensive and Integrated School Psychological Services as the guiding framework. Thirteen full‐time, school‐based practitioners from across the US participated in semi‐structured interviews. Constant‐comparative analysis was used to generate themes. Results indicated that practitioners experienced a number of systemic barriers to (e.g., heavy caseload; inconsistent district policies, priorities, and role definitions; lack of stakeholder involvement) and facilitators of (e.g., resources, graduate training and professional development) comprehensive and integrated service delivery. Participants’ perspectives regarding changes needed to expand their services focused on systemic issues as well. Implications for research and practitioners’ efforts to advocate for systems change are discussed.  相似文献   
55.
56.
Even though several studies have reported positive attitudinal outcomes from context-based chemistry programs, methodological obstacles have prevented researchers from comparing satisfactorily the chemistry-learning outcomes between students who experience a context-based program with those who experience a content-driven program. In this narrative inquiry we are able to address the question: how do the recalled experiences of a student and her teacher in context-based and concept-based chemistry programs compare? From the student’s unique perspective of experiencing both programs with the same teacher, we have constructed our collective account around four themes; namely, the extent to which the student makes connections between chemistry concepts and real-world contexts, developing research independence through engaging in extended experimental investigations related to contexts, learning chemistry concepts through contexts, and conceptual sequencing in a context-based program. The student reported real-world connections between chemistry concepts and contexts, found her engagement in the context-driven tasks interesting and productive, and identified connected sequences of concepts across the contexts studied. Despite difficulties for teachers who are required to shift pedagogies, the student’s lived experiences and outcomes from a context-based program provide some encouragement in working through these issues.  相似文献   
57.
The relationship between the construct of mental attention and “giftedness” is not well established. Gifted individuals could make effective use of their executive functions and this could be related to their mental attentional capacity. The dialectic constructivist model developed by Pascual-Leone introduced the concept of mental attention or “effort”, relating it to mental capacity. The aim of this study is to investigate whether the measurement of mental capacity (M-measurement) is differential for a group of children with high IQs. 110 students between 4 and 18 years old participated in this study. Some were Gifted (n=70) and others Non-Gifted (n=40). Wechsler-R Scale and the Figural Intersection Test were administered to all participants. An interesting pattern was found in the younger groups. The gifted scored higher than the non-gifted in the Figural Intersection Test and much higher than their theoretical M. The non-gifted scored quite close to their theoretical M (based on age). In the oldest group, the gifted again achieved higher scores, but now they scored at the theoretical level, and the non-gifted underperformed.  相似文献   
58.
This study explored pre-service secondary science teachers’ perceptions of classroom emotional climate in the context of the Bhutanese macro-social policy of Gross National Happiness. Drawing upon sociological perspectives of human emotions and using Interaction Ritual Theory this study investigated how pre-service science teachers may be supported in their professional development. It was a multi-method study involving video and audio recordings of teaching episodes supported by interviews and the researcher’s diary. Students also registered their perceptions of the emotional climate of their classroom at 3-minute intervals using audience response technology. In this way, emotional events were identified for video analysis. The findings of this study highlighted that the activities pre-service teachers engaged in matter to them. Positive emotional climate was identified in activities involving students’ presentations using video clips and models, coteaching, and interactive whole class discussions. Decreases in emotional climate were identified during formal lectures and when unprepared presenters led presentations. Emotions such as frustration and disappointment characterized classes with negative emotional climate. The enabling conditions to sustain a positive emotional climate are identified. Implications for sustaining macro-social policy about Gross National Happiness are considered in light of the climate that develops in science teacher education classes.  相似文献   
59.
An interview and an intervention study are reported. Interview findings extend research on the positive relationship of parent involvement to school success. That is, although most of the low income families reported low-moderate participation, a postive relationship was found between parent involvement and school adjustment as early as kindergarten. With respect to negative valuing and barrier interpretations of low participation, the data support the latter; all but a few parents reported positive attitudes toward school involvement, while the majority indicated significant barriers. In comparing Latino and non-Latino groups, the former reported more barriers. Within the Latino group, parents whose children had made a good school adjustment indicated the most participation. Non-English proficient parents reported more barriers than those proficient in English but comparable degrees of involvement. In the intervention study, a simple strategy resulted in more treatment than control parents attending a school event. Differences in attendance were related to ethnicity and language.This work was carried out in conjunction with a dropout prevention demonstration project conducted as a collaborative effort of the School Mental Health unit (Janelle Munn, Director) and Dropout Prevention unit (Pete Martinez, Director) of the Los Angeles Unified School District and the School Mental Health Project at UCLA (Howard Adelman and Linda Taylor, Co-directors). Partial support for the project came from the U.S. Department of Education. The authors, of course, assume full responsibility for the contents, but we want to take this opportunity to acknowledge the contributions of participating schools and project staff (especially Mary Beth DiCecco and Alison McAlpine). And although she declined author credit, this work could not have been accomplished with the many contributions of Linda Taylor, the project director. We would also like to thank Regina DeWitter, Teresa Gonzales, Kathy Eides and the many other UCLA students who assisted in various phases of the research.  相似文献   
60.
茶叶香气成分的研究--乌龙茶与鲜茶香气成分的比较   总被引:9,自引:0,他引:9  
报道了用同时蒸馏-萃取装置分别提取乌龙茶与鲜茶香气成分,测得乌龙茶的香气成分含量为3.65%.鲜茶的香气成分含量为2.40%。用GC/MS法分别从乌龙茶与鲜茶香气成分中分离并确定出42种和19种化学成分,并对香气化学成分及含量进行了对比。  相似文献   
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