Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Acta Geophysica

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Northern Algeria

Sortuj według:

Ogranicz wyniki do:

Regional relations converting the surface and body wave magnitudes to moment magnitude for Northern Algeria using the general orthogonal regression method

Khemis Asma, Athmani Allaeddine

Acta Geophysica

2023

Vol. 71, no. 6

2747--2762

The existence of several magnitude scales in the compiled earthquake catalogs of a specific region has made the development of regional relations connecting magnitude scales a necessity, especially for creating a homogeneous seismic catalog in which all magnitudes should be converted to a preferred magnitude scale. To consistently estimate all magnitude ranges and avoid the saturation problem for large earthquakes, the preference is always given to the moment magnitude Mw scale, wherein the most complete and reliable catalog used worldwide is the Global Centroid Moment Tensor (GCMT). However, to our knowledge, no study has yielded regional (in Algeria) relationships for converting different magnitudes to the moment magnitude (Mw,GCMT). The main reason is typically due to the lack of data pairs of different magnitude scales with Mw (GCMT). To overcome this issue, in this research paper, the moment magnitudes data used for northern Algeria (the area bounded by 32° to 39° N and 3° W to 10° E) have been taken principally from the GCMT catalog and enhanced with the European-Mediterranean Regional Centroid Moment Tensor catalogs RCMT and ZUR-CMT. Regarding this latter, it has been demonstrated in the literature that for the Mediterranean regions, a minor correction should be addressed before merging its data with the GCMT and RCMT catalogs, which are perfectly correlated. To accomplish this task, the magnitude scales tested against Mw are the surface wave magnitude, MS, and the body wave magnitude mb issued from the international seismological sources of ISC and NEIC for the same boundaries. As long as the earthquake magnitudes, in general, are affected by errors of comparable size, the best and most reliable regression method that considers the errors in both dependent and independent variables for linear conversion problems is the General Orthogonal Regression, which is adopted and applied herein to develop the regional relations.

Forecasting daily flow rate-based intelligent hybrid models combining wavelet and Hilbert–Huang transforms in the mediterranean basin in northern Algeria

Abda Z., Chettih M.

Acta Geophysica

2018

Vol. 66, no. 5

1131--1150

The modelling of the rainfall–runoff relationship plays an important role in risk reduction and prevention against water-related disasters and in water resources management. In this research, we have modelled the rainfall–runoff relationship using intelligent hybrid models for forecasting daily flow rates of the Sebaou basin located in northern Algeria. As such, two hybrid approaches of artificial intelligence have been used in this study. These approaches are based on the adaptive neuro-fuzzy inference system combined with hydrological signal decomposition techniques. The first is derived from the Hilbert–Huang transform called the empirical mode decomposition and the other is derived from the discrete wavelet transform called multiresolution analysis. The results obtained seem to be very encouraging and the techniques appear promising. The performances of the hybrid models are relatively much higher than the other models used for comparison in this study. Although the technique of parallel computing has been used and despite the power of the computing station, the relatively long computation time is the main disadvantage of these models.