geophysical techniques remain the only ways to remotely and non-destructively sense the earth’s near subsurface and as such have the most promising prospect for rapid and accurate detection of underground tunnels. today, electrical resistivity and seismic refraction geophysical methods have been greatly developed to identify structures and underground cavities. in this study, the ability of the...

because of urgent needs of groundwater resources in the tochal region of north tehran, an integration of electric and electromagnetic methods was applied to investigate the location and the direction of water bearing fractures. first, the vlf electromagnetic profiling was performed on suitable places and two locations were detected for supplementary resistivity surveys. then, a number of vertic...

magnetotelluric (mt) method is an electromagnetic technique that uses the earth natural field to map the electrical resistivity changes in subsurface structures. because of the high penetration depth of the electromagnetic fields in this method (tens of meters to tens of kilometers), the mt data is used to investigate the shallow to deep subsurface geoelectrical structures and their dimensions....

In this paper, a nonlocal foundation model is proposed to analyze the vibration and instability of a Y-shaped single-walled carbon nanotube (Y-SWCNT) conveying fluid. In order to achieve more accurate results, fourth order beam theory is utilized to obtain strain-displacement relations. For the first time, a nonlocal model is presented based on nonlocal elasticity and the effects of nonlocal fo...

the direct way to access the petrophysical property of hydrocarbon reservoir is based on well data but due to its high cost, the seismic data has been used to obtain these parameters. for this purpose, many different methods are available and each has its own advantages and limitations. from these methods the seismic inversion is the best tool to study the reservoir characterization. the outcom...

The skin effect and topological edge states in non-Hermitian system have been well-studied, the second-order corner modes also proposed recently. In this paper, we construct nested tight-binding formalism to research analytically, which is a direct description of generic model without other assumptions. Within formalism, obtain exact solutions zero-energy for four-band model. We validate hybrid...