The performance of high resolution particle velocimetry : algorithm, simulations and experiments

In this report we investigate the performance of particle tracking, exploring the influence of an increasing amount of estimators. Basically, a simple method to determine particle matchings was used. Then, first, temporal extrapolation as well as spatial interpolation are employed. Second, a PlY processing step was incorporated. Tests from simulations show that at relatively high seeding densities the performance was increased with a factor of 4 and 13 for the first and second step, respectively. In a physical experiment of a wake behind a heated cylinder a clear performance improvement in the case of PlY preprocessing was observed

The performance of a new PTV algorithm applied in super-resolution PIV

In this paper, we investigate the performance of particle tracking, exploring the influence of an increasing amount of estimators. Basically, a simple method to determine particle matchings was used. Then, first, temporal extrapolation as well as spatial interpolation are employed. Second, a PIV processing step was incorporated. Tests from simulations show that at relatively high seeding densities the performance was increased by a factor of 4 and 13 for the first and second step, respectively. In a physical experiment of a wake behind a heated cylinder, a clear performance improvement in the case of PIV preprocessing was observed

Treatment of defaecation problems in children: the role of education, demystification and toilet training

To evaluate the effect of education in children with chronic defaecation problems, a prospective 6-week intervention study was designed. A total of 54 children (5-14 years) underwent an education programme, with demystification of symptoms and advice about diet and toilet training. The present treatment was continued. After 6 weeks, children with persistent problems received biofeedback training with a follow up of 1 year. The intervention programme was successful in 8 children (15%). Biofeedback training was successful in 49% of the remaining group after 1 year. CONCLUSION: A total of 15% of the children with chronic defaecation problems seen at a referral centre could surprisingly be helped by a simple education programme with, demystification and toilet training. Further studies evaluating treatment in children with defaecation problems should account for the primary effect of these measure