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Abstract This study examined dissonance in physical activity (PA) between two youth-specific hip-derived intensity cut-points for the Actiwatch (AW), and compared PA between hip and wrist placements using site-specific cut-points. Twenty-four children aged 11.2?±?0.5 years wore the AW on the right hip and non-dominant wrist during a typical school day. Minutes of sedentary behaviour and vigorous activity were greater using Puyau et al. (2002) cut-points, but light, moderate, and moderate-to-vigorous (MVPA) were greater when derived using Puyau et al. (2004) cut-points (P?0.01). Total hip activity counts were lower than wrist. Sedentary minutes were greater at the hip, but minutes of light, vigorous and MVPA were lower (P?0.01). Moderate minutes were greater at the hip, but differed only when applying the Puyau et al. (2004) cut-points (P?0.01). In conclusion, data comparisons between two hip derived AW cut-points and between hip and wrist data are inappropriate. Future researchers using the AW at the hip should present data reduced using both published cut-points. As hip and wrist data differ, the wrist placement is preferable as it will likely increase children's compliance to monitoring protocols due to reduced obtrusiveness compared to the hip. 相似文献
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This paper proposes a new sliding mode observer for fault reconstruction, applicable for a class of linear parameter varying (LPV) systems. Observer schemes for actuator and sensor fault reconstruction are presented. For the actuator fault reconstruction scheme, a virtual system comprising the system matrix and a fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix is instrumental in simplifying the synthesis procedure to create the observer gains to ensure a stable closed-loop reduced order sliding motion. The ‘output error injection signals’ from the observer are used as the basis for reconstructing the fault signals. For the sensor fault observer design, augmenting the LPV system with a filtered version of the faulty measurements allows the sensor fault reconstruction problem to be posed as an actuator fault reconstruction scenario. Simulation tests based on a high-fidelity nonlinear model of a transport aircraft have been used to demonstrate the proposed actuator and sensor FDI schemes. The simulation results show their efficacy. 相似文献
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Differences in racial socialization practices and their effects were examined in a sample of 241 African American 1st graders (average age 6.59 years) living in an urban area. Child outcomes included cognitive development, receptive language skills, and child problem behavior. The cultural environment of the home was associated with higher cognitive scores for boys living in high negative social climate and low social capital neighborhoods and for girls living in high social capital neighborhoods. The positive association of promotion of mistrust and child behavior problems was magnified in neighborhoods that had low levels of social capital. A high negative social climate in the neighborhood attenuated the positive association between preparation for bias/promotion of mistrust and externalizing problems. 相似文献
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Matt Allwood Kate Allen Anna Price Rachel Hayes Vanessa Edwards Susan Ball 《Emotional and Behavioural Difficulties》2013,18(4):361-371
ABSTRACTThis paper assesses the reliability and validity of the teacher-completed Pupil Behaviour Questionnaire (PBQ), by comparing it to the already extensively validated teacher-completed Strengths and Difficulties Questionnaire (SDQ). Participants included 2074 primary school children participating in a universal school-based trial and 41 vulnerable children who were taking part in a study exploring the impact of exclusion from school. Exploratory factor analysis results (first factor accounts for 80.8% of the variation in the items) and the high Cronbach’s alpha value of 0.85 indicate that the PBQ consists of one substantive factor/dimension. Strong correlations between the total PBQ score and the conduct sub-scale (Spearman’s correlation coefficient (rs) = 0.67) and total difficulties score (rs = 0.59) of the SDQ indicate convergent validity. This study suggests that the PBQ is a reliable measure, and provides some evidence of validity. Further work is needed to test the PBQ in an older, more diverse populations and to measure sensitivity to change. 相似文献
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Matthew S. Crow Richard M. Hough Sr Jason Mosley John Ortiz Smykla Kimberly M. Tatum 《Journal of Criminal Justice Education》2013,24(3):417-431
This article introduces readers to the philosophy and design of team-based learning (TBL), a method developed by Dr. Larry Michaelsen that was influenced by literature in organizational psychology and pedagogy documenting what actually motivates adults to learn and how they master higher order learning skills. We describe how TBL was implemented in several criminal justice courses and illustrate how this method has drastically reduced student apathy, increased attendance, improved performance, and eliminated frustration for both instructors and students. Additionally, we reflect on how this method has reshaped our roles as educators. 相似文献