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In this work, an attempt is made to simulate the skin temperature profile of breasts in the presence of Cysts. For the first time a study comparing the temperature profiles of normal breasts with Breast Cysts is undertaken. Heat transfer mechanism is modelled as the Penne's Bio-heat equation on 2D breast sections. The equation is solved using the Finite Element Method. The Cysts are simulated for typical depths and sizes. It is observed that for Cysts at depths greater than and of sizes less than . the effect on the surface temperature is negligible. It is also found that in all configurations surface temperature drops. Cyst of maximum radius when placed closest to the skin surface, the temperature declines the most. Therefore this study seems to help in reducing the false positive rate during screening and in the early diagnosis of breast cancer using infrared imaging.

Recently published experimental works on remotely bonded fiber Bragg grating (FBG) ultrasound (US) sensors show that they display some unique characteristics that are not observed with directly bonded FBG sensors. These studies suggest that the bonding of the optical fiber strongly influences how the ultrasound waves are coupled from the structure to the FBG sensor. In this paper, the analytical model of the structure-adhesive-optical fiber section, treated as an ultrasound coupler, is derived and analyzed to explain the observed experimental phenomena. The resulting dispersion curve shows that the ultrasound coupler possesses a cutoff frequency, above which a dispersive longitudinal mode exists. The low propagation speed of the dispersive longitudinal mode leads to multiple resonances at and above the cutoff frequency. To characterize the resonant characteristics of the ultrasound coupler, a semi-analytical model is implemented and the scattering parameters (S-parameters) are introduced for broadband time-frequency analysis. The simulation was able to reproduce the experiment observations reported by other researchers. Furthuremore, the behaviors of the remotely bonded FBG sensors can be explained based on its resonant characteristics.

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We investigate the relationship between the average profile height and the average plastic strain of a grain in a polycrystalline material under plastic tensile strain using Crystal Plasticity Finite Element Method (CPFEM). The simulation consists of using an anisotropic grain embedded in an isotropic sample undergoing tensile plastic deformation. 150 different lattice orientations for the embedded anisotropic grain are used to represent all possible grain orientations. We found that plastic strain in the loading direction is not related to the surface profile height. However, the plastic strains in the direction normal to the surface and the transverse direction are linearly proportional to the average profile heights, irrespective of the grain orientation. The magnitude of the plastic strain in the direction normal to the surface decreases with increasing surface profile height. It is vice versa for plastic strains in the transverse direction. These results establish a possibility of determining a grain’s plastic strains from the profile height.