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Using numerical modelling it is possible to anticipate unfavorable wave conditions for port activity. In particular, using coupled numerical models it is possible to include a larger number of variables, parameters, processes and interactions with focus on improving the representation and precision of processes that occur in the environment. This paper presents a numerical simulation system applied to the coast of central Chile using a coupled tool, which includes the wave model Wavewatch III (WW3), the hydrodynamic model Coastal and Regional Ocean Community (CROCO) and the atmospheric model Weather Research and Forecasting (WRF). The coupled modeling system accounts a oneway coupling from the WRF variables that CROCO and WW3 use as input, and a two-way coupling between the CROCO and WW3 models. The latter is developed through the implementation of the coupler software Ocean Atmosphere Sea Ice Soil (OASIS-MCT3) and the use of coupling tools provided by CROCO. Model results are contrasted with wave instrumental observations made by the National Hydrographic and Oceanographic Data Center of Chile (CENDHOC) using statistics error parameters such as bias, mean square error, and correlation. The hydrodynamic coupled simulations present a better adjustment to the measurements compared to those without coupling revealing a lower bias for significant wave height and mean directions. Likewise, higher values of the correlation coefficients are found in significant wave height with the hydrodynamic coupled tool. [ABSTRACT FROM AUTHOR]

This paper analyzes the impact it causes on the rates of electric power quality, a significant number of nonlinear loads belonging to a computer center and connected to a three-phase. A simple computational method is presented that can be used to analyze the effects caused by loads with a high level of distortion. Different models of personal computers (PCs), monitors and printers were tested in laboratory for the purpose of recording the current signals and the main electrical parameters. With these results and ATP (Alternative Transient Program) program assistance equivalent models of equipment were simulated to evaluate the different phenomena that cause the current harmonic components. The effects of attenuation and diversity are analyzed considering different scenarios: models of PCs identical but on different operating systems, PCs, monitors and printers combined. Simulations showed that a major natural harmonic mitigation occurs due to changes in rates of current harmonic distortion of the devices studied, and the impedance of the power line. For any combination of equipment there is a reduction THDI 14% and 40% depending on the inductive reactance-resistance ratio of the power line. The simulated results were compared with measurements in the data center of a utility company with 120 PCs distributed in a three-phase network. The monitoring was performed using a network analyzer over a week, recording line currents, rates of current and voltage distortion with their harmonic components. [ABSTRACT FROM AUTHOR]