Taking wind into account in the design of waste stabilisation ponds.

Up to now, most investigations on the dependency of the fluid flow patterns and performance of waste stabilisation ponds (WSPs) on wind speed and direction and pond layout have been performed using 2D and 3D CFD steady state isothermal models. 3D non steady state models integrating thermal processes and boundary conditions taking into account the full influence of meteorological factors are likely to provide more realistic predictions of WSP performance. Such modelling was undertaken for 4 pond layouts, 2 without baffles and 2 with baffles. Wind speed and direction were kept constant throughout each simulation while other meteorological forcings were derived from field measurements. Twelve wind directions and 2, 4 and 6 m s(-1) wind speeds were considered for each WSP layout. Simulations allowed verifying that the pond performance is dependent on the wind direction and velocity, that baffles may improve WSP performance and that the addition of well-designed baffles has the advantage of reducing its sensitivity to the wind.

Urban flooding: one-dimensional modelling of the distribution of the discharges through cross-road intersections accounting for energy losses.

Many investigations have been carried out in order to develop models which allow the understanding of complex physical processes involved in urban flooding. The modelling of the interactions between overland flows on streets and flooding flows from rivers and sewer networks is one of the main objectives of recent and current research programs in hydraulics and urban hydrology. However, the modelling of the discharge distribution in the street network with crossroad needs further research due to the complexity of the flow through junctions. This paper outlines the ability of the improved one-dimensional CANOE software to simulate the street flows through the virtual network (developed under the Hy(2)Ville French National project framework) with several cross-roads. The improvements are done by adding in CANOE the energy losses coefficients deriving from the calibration phase based on the experimental study of the flow through small scale physical model of cross-road channels. Comparisons between 1D and 2D simulated distribution of discharges through the virtual network show a good agreement for the global distribution. However, large differences are observed focusing on the individual cross-road intersections in the virtual network.

Fluid flow pattern and water residence time in waste stabilisation ponds.

As treatment processes are kinetic-dependent, a consistent description of water residence times is essential to the prediction of waste stabilization ponds performance. A physically-based 3D transient CFD model simulating the water velocity, temperature and concentration fields as a function of all influent meteorological factors--wind speed and direction, solar radiation, air temperature and relative humidity--was used to identify the relationships between the meteorological conditions and the hydrodynamic patterns and water residence times distributions in a polishing pond. The required meteorological data were recorded on site and water temperatures recorded at 10 sampling sites for 141 days. Stratification events appear on very calm days for wind speeds lower than 3 m s(-1) and on sunny days for wind speeds lower than 5 m s(-1). De-stratification is related to two mixing processes: nightly convection cells and global mixing patterns. Numerical tracer experiments show that the results of the flow patterns can be evaluated using the dispersed flow regime approximation and, for wind speeds exceeding 6 m s(-1), the completely stirred tank reactor assumption.

One-dimensional modelling of the interactions between heavy rainfall-runoff in an urban area and flooding flows from sewer networks and rivers.

Many investigations have been carried out in order to develop models which allow the linking of complex physical processes involved in urban flooding. The modelling of the interactions between overland flows on streets and flooding flows from rivers and sewer networks is one of the main objectives of recent and current research programs in hydraulics and urban hydrology. This paper outlines the original one-dimensional linking of heavy rainfall-runoff in urban areas and flooding flows from rivers and sewer networks under the RIVES project framework (Estimation of Scenario and Risks of Urban Floods). The first part of the paper highlights the capacity of Canoe software to simulate the street flows. In the second part, we show the original method of connection which enables the modelling of interactions between processes in urban flooding. Comparisons between simulated results and the results of Despotovic et al. or Gomez & Mur show a good agreement for the calibrated one-dimensional connection model. The connection operates likes a manhole with the orifice/weir coefficients used as calibration parameters. The influence of flooding flows from river was taken into account as a variable water depth boundary condition.

Resultados de la terapia grupal en un programa multicomponente para dejar de fumar / Results of group therapy in a multicomponent program to quit smoking

Objetivos: La descripción y la evaluación de la eficacia de la terapia para el tratamiento del tabaquismo, con un programa multicomponente y de intervención grupal para la deshabituación del tabaco. Pacientes y método: Los grupos de tratamiento de tabaquismo se ofrecían en la sede de la Junta Provincial de la AECC en Valencia. El programa multicomponente se desarrollo durante siete sesiones con una frecuencia semanal, y dos sesiones más de seguimiento, constaban de una sesión de información médica y seis sesiones de terapia psicológica. La intervención psicológica se distribuía en cuatro fases: la fase de toma de decisión, la fase de preparación, la fase de abandono y la fase de mantenimiento. Se realizaron un total de 12 grupos, el número total de participantes fue de 119. Se realizaron análisis descriptivos de los datos. Resultados: La adherencia al tratamiento es del 82,4% (n = 98)de los 119 sujetos que iniciaron el tratamiento. Respecto a la eficacia del tratamiento que persigue el abandono del hábito de fumar, se consiguieron al finalizar las siete semanas que dura la terapia en un 60%, manteniendo una abstinencia continua. En los seguimientos el porcentaje de abandono va de un 34% al mes a un 20% a los cuatro meses de finalizarla terapia. Conclusiones: La eficacia de la intervención varía de un 60% a las siete semanas del día del abandono a un 20% a las 19 semanas del día D. Pensamos que las 19 primeras semanas después de haber dejado el hábito de fumar son las más críticas para la recaída, y que se debería incidir más en los contenidos y pautas de prevención de recaída (AU)

Objectives: The description and evaluation of the efficacy of therapy for treatment of the smoking habit with a multicomponent program and group intervention for the dehabituation of smoking. Patients and method: The groups for smoking cessation treatment are offered in the site of the Provincial Board of the Spanish Association Against Cancer in Valencia. The multicomponent program is conducted for 7 weekly sessions and 2 more follow-up sessions. They are made up of a medical information session and six psychological therapy sessions. The psychological intervention is distributed into four phases: decision making phase, preparation phase, abandonment phase and maintenance phase. A total of 12 groups were held, and the total number of participants was 119. Descriptive analyses of the data were made. Results: Treatment adherence is 82.4% (n = 98) of the 119 subjects who initiated treatment. Regarding efficacy of the treatment to quit the smoking habit, at the end of the seven week duration of the therapy, 60% achieved it, with continuous abstinence. In the follow-ups, the percentage of abandonment went from 34% at one month to 20% at four months of completing the therapy. Conclusions: The efficacy of the intervention varies from 60% at 7 weeks from the day of abandonment to 20% at 19 weeks of day D. We think that the first 19 weeks after having quit smoking are the most critical for relapse and that more emphasis should be made on the contents and guidelines for relapse prevention (AU)