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21.
This study aimed to identify the maturity-related differences and its influence on the physical fitness, morphological and performance characteristics of young elite paddlers. In total, 89 kayakers and 82 canoeists, aged 13.69 ± 0.57 years (mean ± s), were allocated in three groups depending on their age relative to the age at peak height velocity (pre-APHV, circum-APHV and post-APHV) and discipline (kayak and canoe). Nine anthropometric variables, a battery of four physical fitness tests (overhead medicine ball throw, countermovement jump, sit-and-reach test and 20 m multistage shuttle run test) and three specific performance tests (1000, 500 and 200 m) were assessed. Both disciplines presented significant maturity-based differences in all anthropometric parameters (except for fat and muscle mass percentage), overhead medicine ball throw and all performance times (pre > circum > post; < 0.05). Negative and significant correlations (< 0.01) were detected between performance times, chronological age and anthropometry (body mass, height, sitting height and maturity status), overhead medicine ball throw and sit and reach for all distances. These findings confirm the importance of maturity status in sprint kayaking and canoeing since the more mature paddlers were also those who revealed largest body size, physical fitness level and best paddling performance. Additionally, the most important variables predicting performance times in kayaking and canoeing were maturity status and chronological age, respectively.  相似文献   
22.
Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing.  相似文献   
23.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   
24.
Many services can be self-provided. An individual user or a user firm can, for example, choose to do its own accounting - choose to self-provide that service - instead of hiring an accounting firm to provide it. Since users can ‘serve themselves’ in many cases, it is reasonable to suspect that they can also innovate with respect to the services they self-provide - possibly without the assistance of service providers.In this paper, we conduct the first quantitative exploration of the importance of services innovation by users, focusing on the field of commercial and retail banking services. We find that 55% of today's computerized commercial banking services were first developed and implemented by non-bank firms for their own use, and 44% of today's computerized retail banking services were first developed and implemented by individual service users rather than by commercial financial service providers. Manual precursors to these services - manual procedures that carried out functions similar to computerized services in our sample - were almost always developed by users as self-services.Our empirical findings differ significantly from prevalent producer-centered views of service development. We speculate that the patterns we have observed in banking with respect to the major role of users in service development will prove to be quite general. If so, this will be an important matter: on the order of 75% of GDP in advanced economies today is derived from services. We discuss the implications of our findings for research and practice in service development.  相似文献   
25.
Software must evolve in order to adapt to new demands and scenarios. In the case of packaged software that can be customized, this evolution implies the maintenance of both out-of-the-box and customized functionality alike. New user interface technologies provide a way to interact with applications that software vendors are forced to incorporate in order to meet new user and market requirements. Packaged software vendors are facing software evolution processes in order to attract more customers and conserve the existing ones. This case analysis describes the evolution of packaged software, Meta4 PeopleNet, towards the addiction of Rich Internet Applications features to a Human and Intellectual Capital Management tool. The findings and lessons learned presented in this case study provide useful insights for packaged software vendors facing software product evolution.  相似文献   
26.
For the general population, sharks have a reputation that does not really fit with their biological and ecological nature. Informal surveys often classify sharks as dangerous, aggressive and/or man-eaters. This apparent common knowledge seems difficult to detach from the conscience of many worldwide zoo visitors, even with the help of shark-focused educational programmes. As so, how can zoos and aquariums contribute to a change in this paradigm? Are the education and conservation strategies effective to the average zoo visitor? In this study, young visitors’ perceptions regarding sharks were assessed with the goal of identifying a valid Learning Progression, thus helping to update and develop different and more effective educational strategies and methodologies. The study took place at Zoomarine, an oceanographic park located in southern Portugal, with visitors aged between 8 and 16. A case study was conducted using a qualitative research approach (drawings and interviews) resulting in a Learning Progression Hypothesis. The proposed Learning Progression is composed of three knowledge levels for the participants’ biological perceptions regarding sharks. The results of this study showed a clear predominance of anthropomorphic and anthropocentric visions, as well as a utilitarian view of sharks and ecosystem, thus conditioning the visitors’ epistemological knowledge.  相似文献   
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28.
This article examines the use of shadow education by students of compulsory secondary education in Spain over the period 2000?2010. The study identifies the proportion of the student population that uses this type of education and examines how the use of shadow education has evolved during this period. Data was drawn from the student questionnaire in the PISA report, which gathered information on extra lessons in the four studies conducted between 2000 and 2009. The study also contrasted the data on the use of extra classes with the socioeconomic profile of students and other indicators of social inequality.  相似文献   
29.
This study reviews empirical data from the U.S. Census, American Community Survey (ACS) and academic journals to explore K-12 and higher educational outcomes pertaining to Southeast Asian American (SEAA) males. We argue that the empirical dismissal of SEAA males in social science research reinforces a longstanding agenda of structural neglect and invisibility. By disaggregating some of the existing data for Cambodian, Hmong, Laotian, and Vietnamese subgroups from the broader “Asian” group, we hope to repudiate the model minority myth and stereotypes related to masculinity. Findings revealed that SEAA males had K-12 and higher educational outcomes that contradict the standard conception of academic and financial success. We situate the findings of the article in a discussion of intersectionality and the mainstream cultural forces that impact SEAA males.  相似文献   
30.
Management literature has identified high-skilled human capital as a crucial dimension of innovation processes at the firm level. In this study, we introduce an alternative view of human capital based on the tasks that firms’ workers perform. We propose a measure of cognitive analytical and interpersonal tasks: the degree of abstractism. We argue that the level of abstractism of a firm has an effect on a firm's propensity to innovate and on its product innovation performance. We hypothesize that while the degree of abstractism has a linear positive relationship with the propensity to innovate, the relationship between abstractism and product innovation performance follows an inverted u-shaped relationship. We find partial support to our hypotheses using data from more than six thousand Portuguese firms. We discuss how these results change our understanding of the relationship between human capital and innovation at the firm level.  相似文献   
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