Flow curvature effects on dynamic behaviour of a novel vertical axis tidal current turbine: numerical and experimental analysis

The paper deals with performances analysis of vertical axis turbine to exploit tidal marine currents. Flow curvature effects on performences of a novel vertical axis turbine have been investuigated. It has been shown that the flow curvature effect allows to design properly an accurate airfoil shape to increase turbine performances

Dynamic behavior of novel vertical axis tidal current turbine: numerical and experimental investigations

This paper presents a summary of the recent work done by the authors regarding the design, construction and test of a novel patented vertical axis and variable pitching blade hydro turbine, named KOBOLD, capable of harnessing clean and renewable energy from marine tidal currents. The KOBOLDturbine, currently moored in Messina Strait, between mainland Italy and Sicily island, is the only existing turbine of this type devoted to exploit tidal currents, and has a 25% global system efficiency. Theoretical analysis and numerical prediction performanceshave been compared and validated with experimental test results on both model and real scale turbines. Moreover, the recent activities in terms of numerical and experimental investigations on vertical axis hydro turbines are presente

Dynamic Behaviour of the Patented Kobold Tidal Current Turbine: Numerical and Experimental Aspects

This paper provides a summary of the work done at DPA on numerical and experimental investigations of a novel patented vertical axis and variable pitching blades hydro turbine designed to harness energy from marine tidal currents. Ponte di Archimede S.p.A. Company, located in Messina, Italy, owns the patented KOBOLD turbine that is moored in the Messina Strait, between the mainland and Sicily. The turbine has a rotor with a diameter of 6 meters, three vertical blades of 5 meters span with a 0.4 m chord ad hoc designed curved airfoil, producing high lift with no cavitation. The rated power is 160 kW with 3.5 m/s current speed, which means 25% global system efficiency. The VAWT and VAWT_DYN computer codes, based on Double Multiple Steamtube, have been developed to predict the steady and dynamic performances of a cycloturbine with fixed or self-acting variable pitch straight-blades. A theoretical analysis and a numerical prediction of the turbine performances as well as experimental test results on both a model and the real scale turbine will be presented and discussed.

Effects of pidotimod and bifidobacteria mixture on clinical symptoms and urinary metabolomic profile of children with recurrent respiratory infections: a randomized placebo-controlled trial

Many preschool children develop recurrent respiratory tract infections (RRI). Strategies to prevent RRI include the use of immunomodulators as pidotimod or probiotics, but there is limited evidence of their efficacy on clinical features or on urine metabolic profile

Cardiopulmonary assessment in primary ciliary dyskinesia.

Background Primary ciliary dyskinesia (PCD) is a rare, usually autosomal recessive disorder of ciliary dysfunction associated with lung involvement, which has a great impact on health. There is limited information concerning the aerobic fitness of children and adolescents with PCD. The aim of this study was to assess cardiopulmonary functional capacity and its relationship with pulmonary function and physical activity (PA) levels in patients with PCD. Design Ten patients with PCD (age 13·2±2·8years) underwent spirometry and cardiopulmonary exercise testing. PA was investigated through a questionnaire. Eight age- and body mass index-matched healthy children were enrolled as controls. Main variables were forced expiratory volume at 1s, peak oxygen uptake (VO 2peak) and time spent in PA. Results Forty per cent of patients with PCD had impaired lung function as expressed by FEV 1<85% predicted. Only patients with impaired lung function exhibited reduced VO 2peak (18·1±7·9mL/kg/min). Time spent in total daily PA was slightly lower in patients than controls, with no difference between patients with normal or reduced lung function. In multiple regression models, male gender (??=0·518, P=0·018), age (??=0·752, P=0·035) and time spent in vigorous PA (??=0·353, P=0·049) were independent predictors of aerobic fitness. Conclusions Assessment of resting pulmonary function and cardiopulmonary functional capacity could contribute to the evaluation of pulmonary impairment in PCD. Given the benefit of physical exercise on airway clearance and on general health and quality of life, patients with PCD should be encouraged to adopt an active lifestyle

Assessment of chest high-field magnetic resonance imaging in children and young adults with noncystic fibrosis chronic lung disease: comparison to high-resolution computed tomography and correlation with pulmonary function.

Magnetic resonance imaging (MRI) has been proposed as a radiation-free alternative to high resolution computed tomography (HRCT) for the assessment and follow-up of chest disorders. Thus far, no study has compared the efficacy of high-field MRI and HRCT in children and adults with noncystic fibrosis (CF) chronic lung disease. The aims of our study were: (1) to assess whether chest high-field MRI is as effective as chest HRCT in identifying pulmonary abnormalities; and (2) to investigate the relationships between the severity and extent of lung disease, and functional data in patients with non-CF chronic lung disease. Forty-one subjects (median age, 13.8 years; range, 5.9-29.3 years; 30 children/11 adults) with primary ciliary dyskinesia (n = 14), primary immunodeficiency (n = 14), or recurrent pneumonia (n = 13) underwent pulmonary function tests, chest HRCT (120 kV, dose-modulated mAs) and high-field 3.0-T MRI (HASTE; transversal orientation; repetition time/echo time/flip angle/acquisition time, infinite/92 milliseconds/150 degrees/approximately 90 seconds). HRCT and MRI images were scored in consensus by 2 raters using a modified version of the Helbich scoring system. The maximal score was 25. HRCT and high-field MRI total scores were 11 (range: 1-20) and 11 (range: 1-17), respectively. There was good agreement between the 2 techniques for all scores (r > 0.8). HRCT and MRI total scores, and extent of bronchiectasis scores were significantly related to pulmonary function tests (r = -0.4, P < 0.05). The MRI mucous plugging score was significantly related to pulmonary function tests (r = -0.4, P < 0.05). Chest high-field 3.0-T MRI appears to be as effective as HRCT in assessing the extent and severity of lung abnormalities in non-CF chronic lung diseases, and might be a reliable radiation-free option to HRCT

A Roadmap to Gamify Programming Education

Learning programming relies on practicing it which is often hampered by the barrier of difficulty. The combined use of automated assessment, which provides fast feedback to the students experimenting with their code, and gamification, which provides additional motivation for the students to intensify their learning effort, can help pass the barrier of difficulty in learning programming. In such environment, students keep receiving the relevant feedback no matter how many times they try (thanks to automated assessment), and their engagement is retained (thanks to gamification). While there is a number of open software and programming exercise collections supporting automated assessment, up to this date, there are no available open collections of gamified programming exercises, no open interactive programming learning environment that would support such exercises, and even no open standard for the representation of such exercises so that they could be developed in different educational institutions and shared among them. This gap is addressed by Framework for Gamified Programming Education (FGPE), an international project whose primary objective is to provide necessary prerequisites for the application of gamification to programming education, including a dedicated gamification scheme, a gamified exercise format and exercises conforming to it, software for editing the exercises and an interactive learning environment capable of presenting them to students. This paper presents the FGPE project, its architecture and main components, as well as the results achieved so far. 2012 ACM Subject Classification Social and professional topics ! Computer science education