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Recognition of urban rusty textures due to degradation of urban and environmental general appearance, and also the necessity of planning for their destruction or reform due to their low resistance against natural disasters such as flood, earthquake, etc., are important. The first step for recognition of these textures as spatial objects is to provide mapping the extents of old textures and to evaluate their surface areas, followed by computation and evaluation of their destruction or reform costs. Modern scientifi...

Nowadays, airborne electromagnetic methods are widely used to investigate subsurface areas. One of these methods is helicopter electromagnetic method. The basis of inverse modeling of frequency-domain HEM data is to solve Mundry’s integral numerically. Various methods have been invented for numerical solution of this integral, such as Laplace transform, fast Hankel coefficients and Jacobian methods. To analyze helicopter electromagnetic data, we need inverse programs which can assist us to achieve the best or ac...

Nowadays, airborne geophysical data can be obtained in low costs rapidly. Among airborne geophysical systems to acquire magnetic, electromagnetic and radiometric data, helicopter geophysical systems play an important role in exploration of mineral deposits in large areas. In general, using airborne systems to measure electromagnetic data, we can obtain two-dimensional conductivity-depth sections, and then, a threedimensional conductivity model from the subsurface of the survey area. Consequently, the lateral and v...

Electromagnetic (EM) methods are among geophysical methods which have many various applications. Besides, EM surveys are carried out rapidly with low costs. Thus, they are being fast developed. The methods, compared to other geophysical methods, have the most various acquisition systems. EM surveys can be carried out in the land, air, sea and borehole. During 1950s in Canada, airborne EM methods, in which helicopter EM (HEM) method is also included, have assisted in mineral exploration valued more than 10 milliard...