We address the problem of estimating seismic velocities inside the earth which is necessary for obtaining seismic images in regular Cartesian coordinates. We derive a relation between the true seismic velocities and the routinely obtained so called ”time migration velocities”, which are some kind of mean velocities. We formulate an inverse problem and show that it is ill-posed. We suggest three...

objective(s): berberine is one of the main alkaloids and it has been proven to have different pharmacological effects including inhibition of cell cycle and progression of apoptosis in various cancerous cells; however, its effects on cancer metastasis are not well known. cancer cells obtain the ability to change their chemokine system and convert into metastatic cells. in this study, we examine...

Submarine pipelines are a safe and energy-efficient mode of gas transport. However, due to the complex manufacturing process harsh operating environment, submarine subject fatigue cracks under long-term cyclic loading. A comprehensive high-precision characterization strategy for can effectively prevent potential safety hazards have significant economic social repercussions. As matter fact, pipe...

Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the earth, i.e. at commonimage-point gathers (CIPs), carry enough information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. Furthermore, inaccurate anisotropy leaves a distinctive signature in CIPs,...

Objective(s): The study aimed to investigate the effects of resveratrol on colorectal cancer HCT116 cells, including cell viability, apoptosis, and migration, and the partial mechanisms focused on hedgehog/gli-1 signaling pathways. Materials and Methods: We chose the appropriate time and concentration of recombinant human Sonic hedgehog (Shh) stimulation by cell viability. The proportion of cel...

High levels of regulated oncogen-alpha (GRO-a) expression have been observed in the liver. GRO-a stimulates proliferation of epithelial cells and induction of rolling and extravascular migration of neutrophils and mononuclear cells. Given the above observations, this chemokine was chosen to be analyzed in freshly isolated and cultured hepatocytes. In this study, hepatocytes (2×106 cell/ml) were...

The standard reverse-time migration (RTM) algorithm is usually described as zero-lag correlation of the backprojected data with the source wavefield. The data are back-projected by a finite-difference algorithm, where each trace acts as a source-time history of a point source at the geophone location. This is a simple and easily understood migration method, but appears inflexible to improvement...

Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at commonimage-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a chal...

Biogeography-Based Optimization (BBO) has recently gained interest of researchers due to its simplicity in implementation, efficiency and existence of very few parameters. The BBO algorithm is a new type of optimization technique based on biogeography concept. This population-based algorithm uses the idea of the migration strategy of animals or other species for solving optimization problems. t...

Both migration deconvolution (MD) and least squares migration (LSM) are capable of improving the resolution and suppress acquisition footprints in migrated images. In this paper, we investigate the relative performance of these two technologies in enhancing migration image quality, suppressing artifacts and computational efficiency. Both MD and LSM were tested on SEG/EAGE overthrust models. The...