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The methodology used in the design of this research was descriptive and correlational, using direct observation of the phenomenon, to record and interpret the different depths to which the suction pipe was submerged and to experimentally study the effects of changes in the variables; flow, diameter and position of the suction pipe on the critical submergence in pumping systems placed in reservoirs with liquid at relative rest to the imminence of the vortex. A correlation between the independent variables and the water level above the top of the suction pipe was sought, performing a series of tests with a vortices generator device, coupled to a pumping system in recirculation, designed and built to simulate different operating conditions for various arrangements, making discrete changes in the diameters and positions of the pipe, as well as the suction flow. The experimental data were analyzed and represented graphically, deducing a dimensionless predictive equation, with the relative submergence as a function of the Reynolds and Froude numbers, which allows the determination of the critical submergence for different fluids and/or different operating conditions. This led to the conclusion that there is a strong functional dependence of the critical submergence respect to the flow and the internal diameter of the suction pipe. This relationship between the critical submergence and the pump flow is direct, and between the critical submergence and the inner diameter of the suction pipe is reverse. [ABSTRACT FROM AUTHOR]

Habitat destruction may cause wildlife population fragmentation and is considered an important factor in small population species extinction. As wildlife populations become smaller, threats to their stability and persistence arise as a result of demographic, environmental and genetic stochastic factors. The aim of this work was to study the effects of population fragmentation on the long term viability of Alouatta palliata and Cebus capucinus populations, at Refugio de Vida Silvestre Privado Nogal, Sarapiquí (RVSPN), Heredia. For this we used the computer software VORTEX to run a population viability analysis (PVA) for both species. The input data of the PVA were taken from the demography structure of the RVSPN, literature sources from the species and from PVA related papers. We evaluated two sets of scenarios: small fragmented populations to reflect the population current state, and one larger and continuous population, to reflect the effect of reforestation actions followed by RVSPN to connect forest fragments. Results suggest that both A. palliata and C. capucinus can survive in isolated forest fragments. However, if different factors as inbreeding depression, catastrophes or habitat loss were incorporated to the scenarios, the small fragmented populations become unstable and the risk of extinction increased for both species. Continuous and larger populations were more robust against the threats incorporated in the scenarios when compared to the current situation of smaller and fragmented populations. The best management option for both species would be to continue reforestation efforts in the area to connect forest fragments, with the result of larger and continuous populations of both species. It is important to continue the observation of both species populations, and to promote a habitat management to reduce the negative effects of stochastic environmental events. [ABSTRACT FROM AUTHOR]

In this work starting from the vortical movement in the space simulation of bagasse particles, that is, in upward helical form, they are gotten the longitude and the height reached by the particles in several conditions, and are shown their behaviour graphics in relation to other parameters that intervene in the process, like a posterior phase of the study done by other national authors and foreigners on the movement of these particles. [ABSTRACT FROM AUTHOR]