Purpose -The aim of this paper is to present and evaluate a methodology for automatically constructing and applying the physiologically-realistic boundary/loading conditions for use in the structural finite element analysis of the femur during various exertion tasks (e.g. gait/walking). Design/methodology/approach -To obtain physiologically-realistic boundary/loading conditions needed in the femur structural finite element analysis, a whole-body musculoskeletal inverse dynamics analysis is carried out and the resulting muscle forces and joint reaction forces/moments extracted. Findings -The finite element results obtained are compared with their counterparts available in literature and it is found that the overall agreement is acceptable while the highly automated procedure for the finite element model generation developed in the present work made the analysis fairly easy and computationally highly efficient. Potential sources of errors in the current procedure have been identified and the measures for their mitigation recommended. Originality/value -The present approach enables a more accurate determination of the physiological loads experienced by the orthopedic implants which can be of great value to implant designers and orthopedic surgeons.

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We propose a dual-polarization optimization method for the bulk sensitivity of silicon-on-insulator (SOI) waveguides by defining a multi-objective function that accounts for the substrate leakage losses. The proposed optimization method was used to design micro-ring resonator bulk sensors with strip, slot, subwavelength grating, and subwavelength grating slot waveguides. The subwavelength grating slot waveguide has a bulk sensitivity of 520 nm/RIU and 325 nm/RIU for the TE and TM modes, respectively, both of which are higher than the bulk sensitivities of strip, slot, and subwavelength grating waveguides. Moreover, our Monte Carlo analysis shows that the subwavelength grating slot waveguide has the highest immunity to fabrication errors.

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To address the necessity for a predictive computational tool for layout design in crack lithography, a tool for nanowire fabrication, a computational study is carried out using finite element analysis, where crack-free edge and crack-crack interactions are studied for various material combinations. While the first scenario addresses the ability to induce a controlled curvature in a nanowire, the latter provides an estimation of the minimum distance which can be kept between two straight nanowires. The computational study is accompanied by an experimental demonstration on Si/SiO2 multilayers. Finite element results are found to be well aligned with experimental observations and theoretical predictions. Stronger interaction is evident with a curved crack front modeling as well as with increasing first and decreasing second Dundurs' parameters. Therefore cracks can be packed closer with decreasing film stiffness.