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971.
Abstract

This study assessed the reliability and validity of segment measured accelerations in comparison to front foot contact (FFC) ground reaction force (GRF) during the delivery stride for cricket pace bowlers. Eleven recreational bowlers completed a 30-delivery bowling spell. Trunk- and tibia-mounted inertial measurement units (IMUs) were used to measure accelerations, converted to force, for comparisons to force plate GRF discrete measures. These measures included peak force, impulse and the continuous force–time curve in the vertical and braking (horizontal) planes. Reliability and validity was determined by intra-class correlation coefficients (ICC), coefficient of variation (CV), Bland–Altman plots, paired sample t-tests, Pearson’s correlation and one-dimensional (1D) statistical parametrical mapping (SPM). All ICC (0.90–0.98) and CV (4.23–7.41%) were acceptable, except for tibia-mounted IMU braking peak force (CV = 12.44%) and impulse (CV = 18.17%) and trunk vertical impulse (CV = 17.93%). Bland–Altman plots revealed wide limits of agreement between discrete IMU force signatures and force plate GRF. The 1D SPM outlined numerous significant (p < 0.01) differences between trunk- and tibia-located IMU-derived measures and force plate GRF traces in vertical and braking (horizontal) planes. The trunk- and tibia-mounted IMUs appeared to not represent the GRF experienced during pace bowling FFC when compared to a gold-standard force plate.  相似文献   
972.
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   
973.
974.
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   
975.
976.
This article assessed changes in the association between single motherhood and children’s verbal cognitive ability at age-11 using data from three cohorts of British children, born in 1958 (n = 10,675), 1970 (n = 8,933) and 2000 (n = 9,989), and mediation analysis. Consistent with previous studies, direct effects were small and insignificant. For those born in 1958 and 1970 indirect effects, operating through reduced economic and parental resources, were associated with −.107-SD to −.156-SD lower attainment. Differences between the two cohorts, and by children’s age when parents separated, were insignificant. For the 2000 cohort, effect sizes for children born to single mothers did not change significantly (−.112-SD) but attenuated for children whose parents separated in early childhood (−.076-SD) or while of school age (−.054-SD).  相似文献   
977.
ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   
978.
ABSTRACT

Charles Spearman and L. L. Thurstone were pioneers in the field of intelligence. They not only developed methods to assess and understand intelligence, but also developed theories about its structure and function. Methodologically, their approaches were not that distinct, but their theories of intelligence were philosophically very different – and this difference is still seen in modern approaches to intellectual assessment. In this article, we describe their theories of intelligence and then trace how these theories have influenced the development and use of intelligence instruments, paying particular attention to score interpretation.  相似文献   
979.
We used data from the 2014–2015 easyCBM assessment system to explore the applied reading intervention characteristics in a sample of 3,074 Grade 1 students (and 5,145 interventions) in school districts applying a multitiered systems of support (MTSS) framework. We describe the number of interventions, number of assessments, the intervention start dates, curricula, instructional strategies, tier, group size, frequency, dosage, total time, and quantitative intensity. We found variance across all instructional variables, with 156 curricula and 59 instructional strategies applied. Based on our data, a “typical” intervention was a Tier 2 intervention that began before October, was delivered for 30 minutes/day for 5 days/week in a group with three to five students, was changed once if at all, and student progress was most likely monitored with word reading fluency measures.  相似文献   
980.
ABSTRACT

This paper analyses to whom Spanish journalists feel responsible. To achieve this objective, we sent out a survey to Spanish journalists to ascertain their opinion on this question. The journalists’ point of view was then compared with that of the general public though six focus groups consisting of Spanish citizens from six cities in Spain (Barcelona, Castellón, Madrid, Sevilla, Mondragón and Santiago de Compostela). Lastly, five in-depth interviews were conducted with journalism experts (e.g., directors of professional journalist associations). The main results show that the journalists feel particularly responsible to their conscience, the journalism code of ethics and their sources. The citizens, in contrast, believe that journalists should be responsible to the audience. We contextualised the Spanish finding in the European context by comparing our results with those derived from a study among European journalists.  相似文献   
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