An optimized mean variance estimation method for uncertainty quantification of wind power forecasts

A statistical optimized technique for rapid development of reliable prediction intervals (PIs) is presented in this study. The mean-variance estimation (MVE) technique is employed here for quantification of uncertainties related with wind power predictions. In this method, two separate neural network models are used for estimation of wind power generation and its variance. A novel PI-based training algorithm is also presented to enhance the performance of the MVE method and improve the quality of PIs. For an in-depth analysis, comprehensive experiments are conducted with seasonal datasets taken from three geographically dispersed wind farms in Australia. Five confidence levels of PIs are between 50% and 90%. Obtained results show while both traditional and optimized PIs are hypothetically valid, the optimized PIs are much more informative than the traditional MVE PIs. The informativeness of these PIs paves the way for their application in trouble-free operation and smooth integration of wind farms into energy systems. © 2014 Elsevier Ltd. All rights reserved.

Kinematic and kinetic improvements associated with action observation facilitated learning of the power clean in Australian footballers

This study investigated the effectiveness of action observation (AO) on facilitating learning of the power clean technique (kinematics) compared with traditional strength coaching methods and whether improvements in performance (kinetics) were associated with an improvement in lifting technique. Fifteen subjects (age, 20.9 ± 2.3 years) with no experience in performing the power clean exercise attended 12 training and testing sessions over a 4-week period. Subjects were assigned to 2 matched groups, based on preintervention power clean performance and performed 3 sets of 5 repetitions of the power clean exercise at each training session. Subjects in the traditional coaching group (TC; n = 7) received the standard coaching feedback (verbal cues and physical practice), whereas subjects in the AO group (n = 8) received similar verbal coaching cues and physical practice but also observed a video of a skilled model before performing each set. Kinematic data were collected from video recordings of subjects who were fitted with joint center markings during testing, whereas kinetic data were collected from a weightlifting analyzer attached to the barbell. Subjects were tested before intervention, at the end of weeks 2 and 3, and at after intervention at the end of week 4. Faster improvements (3%) were observed in power clean technique with AO-facilitated learning in the first week and performance improvements (mean peak power of the subject's 15 repetitions) over time were significant (p < 0.001). In addition, performance improvement was significantly associated (R = 0.215) with technique improvements. In conclusion, AO combined with verbal coaching and physical practice of the power clean exercise resulted in significantly faster technique improvements and improvement in performance compared with traditional coaching methods.

Structure and thickness optimization of active layer in nanoscale organic solar cells

 This paper presents the development of a two-dimensional model of multilayer bulk heterojunction organic nanoscale solar cells, consisting of the thickness of active layer and morphology of the device. The proposed model is utilized to optimize the device parameters in order to achieve the best performance using particle swarm optimization algorithm. The organic solar cells under research are from poly (3-hexylthiophene) and [6,6]-phenyl C61-butyric acid methyl ester type which are modelled to be investigated for performance enhancement. A three-dimensional fitness function is proposed involving domain size and active layer thickness as variables. The best results out of 20 runs of optimization show that the optimized value for domain size is 17 nm, while the short-circuit current vs. voltage characteristic shows a very good agreement with the experimental results obtained by previous researchers. © 2014 Springer Science+Business Media New York

Prevalence and stability of active play, restricted movement and television viewing in infants

This study describes engagement in and stability of physical activity and sedentary behaviours in early life, and assesses associations with sex, maternal education and developmental stage. Maternal-report data at child age 4, 9 and 20 months were collected from 542 families in the Melbourne Infant Feeding Activity and Nutrition Trial Program. Parents estimated average time per day their child spent in active pursuits or pursuits that restricted movement. With increasing age, children generally spent more time in active pursuits and watching television, and less time in situations that restrict movement. Associations were found with age of developmental milestone attainment but not sex or maternal education. Stability over time was strongest for television viewing (β = 0.34–0.38) and time spent outdoors (β = 0.27–0.33). Contrary to guidelines, television viewing increased and showed stability, suggesting a need to target this behaviour very early in life to achieve optimal longer term outcomes.

Stepping out of our comfort zones: pre-service teachers' responses to a critical analysis of gender/power relations in sexuality education

This paper discusses pre-service teachers' responses to a critical analysis of gender/power relations using examples from a final assessment for an intensive elective unit called Teaching Sexuality in the Middle Years. This unit critically examines gender/ power relations, the production of difference, heteronormativity and pleasure and desire, employing a feminist post-structural framework. Despite the focus on critical thinking, reflection and interrogating structural inequalities in this unit some students were resistant or unable to engage with this approach in their assessments, although appearing to do so in workshops. We consider the broad range of sexuality education discourses mobilised by this unit to try to make sense of what looks like resistance but may be something more complex and difficult to negotiate. The paper ends with a consideration of some of the implications of this approach for practice.

Practices of active citizenship among migrant youth: beyond conventionalities

© 2015 Taylor & Francis This paper discusses the empirical manifestations of the notion of active citizenship in the context of the experiences of migrant youth. It focuses on the practices of active citizenship through involvement in social networks and creative civic engagement. In doing so, the article examines the complex and multi-faceted nature of social networking among migrant youth and the extent to which their approach to engagement is dependent on the specificities of the local environment, the type of social issues involved, and the cultural norms of one's own cultural heritage. Key empirical insights are derived from quantitative and qualitative research conducted among migrant youth of African, Arabic-speaking and Pacific Island backgrounds in Australia. These empirical insights are used to examine the changing perceptions of active citizenship among migrant youth, and the possibilities offered through non-traditional networks to engender civic engagement and social participation.

A comparative study of different power system stabilizers for dynamic stability analysis

Power system stabilizers (PSSs) are extensively used to ensure the dynamic stability of power systems through the modulation of excitation signals supplied to synchronous generators. This paper presents a comparative study of two different PSSs: STAB1 and IEEEST. The stabilizers are designed for the linearized model of a single machine infinite bus (SMIB) system with different loads. Both time-and frequency-domain simulations are carried out to investigate the performance of these stabilizers. For all PSSs, the time-domain simulations are performed by applying a three-phase short-circuit fault at the terminal of the synchronous generator. These simulation results are compared against the open-loop characteristics of the SMIB system where no PSS is implemented. Simulation results demonstrate that the speed-fed PSS provides more damping as compared to frequency- and power-fed stabilizers.

Prescription and over-the-counter pain medication in arthritis: awareness of active ingredients and attitudes to medication borrowing and sharing

Background:
Many Australians with arthritis self-manage their pain with prescription and/or over-the-counter pain medications, containing paracetamol. If taken appropriately, these medications are relatively safe; however, if mismanaged through patients' iinability to understand medication labels and instructions, these medications may cause adverse drug events and/or toxicities.
Aim:
This study explored the prescription and over-the-counter pain medications most commonly used by people with arthritis and the ability of these patients to correctly identify paracetamol as an active ingredient in commonly available preparations. The study also investigated the functional health literacy of these patients and their inclination to borrow and/or share pain medications.
Method:
Adult participants diagnosed with arthritis were invited to complete an anonymous survey which included questions about their prescription and over-the-counter pain medications; their medication borrowing and sharing behaviours; their functional health literacy; and their knowledge about preparations containing paracetamol as an active ingredient.
Results:
Most of the 254 participants used analgesic agents containing paracetamol, as combination tablets (paracetamol 500 mg and codeine 30 mg) or paracetamol-only tablets (paracetamol 665 mg) to self-manage their pain. Respondents with low functional health literacy scores were significantly less likely to identify paracetamol as an active ingredient in both combination and paracetamol-only pharmaceutical products, and were more likely to guess or did not know how to identify that paracetamol was an active ingredient in these products. Almost 30% of the respondents indicated that they had and/or intended to borrow/share their over-the-counter
pain medications whereas less than 10% suggested that they had and/or intended to borrow/share their prescription pain medication.
Conclusion:
Australians with arthritis, especially those with low functional health literacy scores, self-managing their pain with paracetamol-containing products, do not always recognise paracetamol as an active ingredient in combination products, and may risk potential paracetamol-related adverse effects and/or toxicities.

A systematic review of economic analyses of active transport interventions that include physical activity benefits

Physical inactivity is one of the leading causes for the growing prevalence of non-communicable diseases worldwide and there is a need for more evidence on the effectiveness and cost-effectiveness of interventions that aim to increase physical activity at the population level. This study aimed to update a systematic review published in 2008 by searching peer-reviewed and unpublished literature of economic evaluations of transport interventions that incorporate the health related effects of physical activity. Our analysis of methods for the inclusion of physical activity related health effects into transport appraisal over time demonstrates that methodological progress has been made. Thirty-six studies were included, reflecting an increasing recognition of the importance of incorporating these health effects into transport appraisal. However, significant methodological challenges in the incorporation of wider health benefits into transport appraisal still exist. The inclusion of physical activity related health effects is currently limited by paucity of evidence on morbidity effects and of more rigorous evidence on the effectiveness of interventions. Significant scope exists for better quality and more transparent reporting. A more consistent approach to the inclusion of benefits and disbenefits would reinforce the synergies between the health, environmental, transport and other sectors. From a transport sector perspective the inclusion of physical activity related health benefits positively impacts cost effectiveness, with the potential to contribute to a more efficient allocation of scarce resources based on a more comprehensive range of merits. From a public health perspective the inclusion of physical activity related health benefits may result in the funding of more interventions that promote active transport, with the potential to improve population levels of physical activity and to reduce prevalence of physical activity related diseases.

The effect of active video games by ethnicity, sex and fitness: subgroup analysis from a randomised controlled trial

BACKGROUND: The prevention and treatment of childhood obesity is a key public health challenge. However, certain groups within populations have markedly different risk profiles for obesity and related health behaviours. Well-designed subgroup analysis can identify potential differential effects of obesity interventions, which may be important for reducing health inequalities. The study aim was to evaluate the consistency of the effects of active video games across important subgroups in a randomised controlled trial (RCT).

FINDINGS: A two-arm, parallel RCT was conducted in overweight or obese children (n=322; aged 10-14 years) to determine the effect of active video games on body composition. Statistically significant overall treatment effects favouring the intervention group were found for body mass index, body mass index z-score and percentage body fat at 24 weeks. For these outcomes, pre-specified subgroup analyses were conducted among important baseline demographic (ethnicity, sex) and prognostic (cardiovascular fitness) groups. No statistically significant interaction effects were found between the treatment and subgroup terms in the main regression model (p=0.36 to 0.93), indicating a consistent treatment effect across these groups.

CONCLUSIONS: Preliminary evidence suggests an active video games intervention had a consistent positive effect on body composition among important subgroups. This may support the use of these games as a pragmatic public health intervention to displace sedentary behaviour with physical activity in young people.

Effects of active video games on body composition: a randomized controlled trial

BACKGROUND: Sedentary activities such as video gaming are independently associated with obesity. Active video games, in which players physically interact with images on screen, may help increase physical activity and improve body composition.

OBJECTIVE: The aim of this study was to evaluate the effect of active video games over a 6-mo period on weight, body composition, physical activity, and physical fitness.

DESIGN: We conducted a 2-arm, parallel, randomized controlled trial in Auckland, New Zealand. A total of 322 overweight and obese children aged 10-14 y, who were current users of sedentary video games, were randomly assigned at a 1:1 ratio to receive either an active video game upgrade package (intervention, n = 160) or to have no change (control group, n = 162). The primary outcome was the change from baseline in body mass index (BMI; in kg/m(2)). Secondary outcomes were changes in percentage body fat, physical activity, cardiorespiratory fitness, video game play, and food snacking.

RESULTS: At 24 wk, the treatment effect on BMI (-0.24; 95% CI: -0.44, -0.05; P = 0.02) favored the intervention group. The change (±SE) in BMI from baseline increased in the control group (0.34 ± 0.08) but remained the same in the intervention group (0.09 ± 0.08). There was also evidence of a reduction in body fat in the intervention group (-0.83%; 95% CI: -1.54%, -0.12%; P = 0.02). The change in daily time spent playing active video games at 24 wk increased (10.03 min; 95% CI: 6.26, 13.81 min; P < 0.0001) with the intervention accompanied by a reduction in the change in daily time spent playing nonactive video games (-9.39 min; 95% CI: -19.38, 0.59 min; P = 0.06).

CONCLUSION: An active video game intervention has a small but definite effect on BMI and body composition in overweight and obese children.

Parents' and children's perceptions of active video games: a focus group study

Energy expenditure studies have shown that playing Active Video Games (AVGs) is positively associated with increases in heart rate and oxygen consumption. It is proposed that playing AVGs may be a useful means of addressing inactivity and obesity in children. This study explored children's and parents' perceptions of AVGs and the likely facilitators and barriers to sustained use of AVGs. Data were gathered using focus group interviews: seven with children, four with adults. Both children and parents reported that AVGs offered a way to increase activity and improve fitness. Barriers to sustained engagement, according to parents, were the cost of AVGs and lack of space in the home to play the games. According to children, the likelihood of long-term engagement with AVGs depended on game content and child age, with AVGs being seen as more appropriate for younger children than teenagers. It would appear that there is potential for AVGs to reduce inactivity in young people. However, barriers to widespread, sustainable adoption would need to be addressed if this potential is to be realized.