Fault reconstruction using a LPV sliding mode observer for a class of LPV systems

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.     

The reliability and validity of the pupil behaviour questionnaire: a child classroom behaviour assessment tool

ABSTRACT

This 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 (r_s) = 0.67) and total difficulties score (r_s = 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.     

The Instructional and Emotional Quality of Parent–Child Book Reading and Early Head Start Children's Learning Outcomes

Research Findings: The objective of this study was to understand how two dimensions of parent–child book-reading quality—instructional and emotional—interact and relate to learning in a sample of low-income infants and toddlers. Participants included 81 parents and their children from Early Head Start programs in the rural Midwest. Correlation and multiple regression analyses were used to test the hypothesis that parental book-reading qualities interact and relate to children's concurrent cognitive and language scores. Exploratory analyses examined if patterns of relationships varied for families who had different home languages (i.e., English, Spanish). Results included that book-reading qualities and home language interacted to predict child scores. Practice or Policy: Findings suggest a need to further explore potentially complex patterns of relationships among parental book-reading behaviors and child learning for diverse families. Understanding these patterns could inform the development of culturally-sensitive intervention approaches designed to support high-quality shared book reading.     

Application of velocity loss thresholds during free-weight resistance training: Responses and reproducibility of perceptual,metabolic, and neuromuscular outcomes

ABSTRACT

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s^?1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L^?1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8–11; B[La], 0.8–1.0; CMJ height, 1.6–2.0; CMJ PPO, 1.0–1.8; CMJ PCV, 0.04–0.06; CMJ 100ms-Impulse, 5.7–11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.     

Vulnerability to Bullying: Teacher-reported conduct and emotional problems,hyperactivity, peer relationship difficulties,and prosocial behaviour in primary school children

Twenty five class teachers completed a "Strengths and Difficulties" assessment for 523 children aged from 7 to 11 years of age. Children self-completed a 39-item "My Life in School" questionnaire. One third of the sample were self-reported victims of bullying behaviour. Boys with poor prosocial skills, emotional problems and general difficulties with social interaction, expression of emotion and hyperactivity were at greatest risk of being bullied. There was no significant effect of age. The data support previous research findings that gender influences the prevalence of bullying but not that younger children are more vulnerable. This study provides new evidence that teachers recognise social behaviour and interactions that can significantly affect whether primary school children are bullied.     

The role of school-based research champions in a school–university partnership

The value of teachers’ engagement in and with research is long recognised and it is acknowledged that school–university research partnerships are one way of enabling such engagement. But we know little about how research-based knowledge is negotiated into school practices. Here we draw on data from nine ‘research champions’, who are teachers in schools which are part of the Oxford Education Deanery, a research partnership with a university department. Taking a cultural/historical approach, the study examined the strategic intentions and actions in the activities of the champions as they negotiated research-based knowledge into their schools. Data comprised 59 completed templates that described what they did and why. Findings revealed differences between those with close links with senior leaders—who could take a whole-school approach—and those whose reach was restricted by their position in school practices. Nonetheless, all the champions carefully selected and targeted research in ways that reflected their knowledge of local contexts. The findings point to the need to incorporate the champion role into school systems and for universities to value the role as they develop their own research agenda.     

Editorial

Knowledge Management Research & Practice -     

Editorial

Knowledge Management Research & Practice -