In this Letter, we report the discovery of a z= 4.88 radio galaxy discovered with a new technique which does not rely on pre‐selection of a sample based on radio properties such as steep‐spectral index or small angular size. This radio galaxy was discovered in the Elais‐N2 field and has a spectral index of α= 0.75, i.e. not ultra‐steep spectrum. It also has a luminosity consistent with being drawn from the break of the radio luminosity function and can therefore be considered as a typical radio galaxy. Using the Spitzer Wide‐Area Infrared Extragalactic Survey (SWIRE) data over this field, we find that the host galaxy is consistent with being similarly massive to the lower redshift powerful radio galaxies (∼1–3L★). However, we note that at z= 4.88, the Hα line is redshifted into the IRAC 3.6 μm filter, and some of the flux in this band may be due to this fact rather than the stellar continuum emission. The discovery of such a distant radio source from our initial spectroscopic observations demonstrates the promise of our survey for finding the most distant radio sources.

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Wind power generation highly depends on the determination of wind power potential, which drives the design and feasibility of the wind energy production investment. This gives an important role to wind power estimation, which creates the need for an accurate wind data analysis and wind energy potential assessments for a given location. Such assessments require the implementation of an accurate and suitable wind distribution model. Therefore, in the quest for a well-fitted model, eight methods for estimating the Weibull parameters are investigated in this paper. The methods were then investigated by employing statistical tools, and their performances have been discussed in terms of various error indicators such as root mean squared error (RMSE), regression error (R2), chi-square (X2), and mean absolute error (MAE). Meteorological data for diverse terrain from 14 provinces with 30 sites scattered across Iran were employed to examine the performance of the investigated methods. The results demonstrated that the empirical method has superiority over the investigated technique in terms of errors.

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