Four-factor mutual authentication scheme for health-care based on wireless body area network

The Journal of Supercomputing - Health-care is one of the major concerns for every individual; however, it is not always possible to physically visit the health-care center in emergency situations....     

Damage-mechanics-based modelling of failure of squeeze-cast AM50 magnesium alloy

Static and impact tests on bars and plates of squeeze-cast AM50 were used to calibrate a failure surface that depends on tri-axiality and Lode angle. Both notched and un-notched bars and plates were tested. Assuming isotropic plastic response, but asymmetry of work hardening in compression and tension, a damage-mechanics-based model is used to model static and impact loading. Predictions using the model are found to be in reasonable agreement with the experimental results; peak loads and ductility are well described by the model, particularly, for engineering applications. Qualitatively, the model predicts the crack growth in good agreement with observations for experiments wherein the tri-axiality is higher. Likewise, the predicted deformation and failure response are in good agreement with the experimental deformation and failure for higher tri-axiality experiments. We suggest that owing to the coarse grain size, at high levels of deformation, the response is not uniform which make continuum-based modelling a challenge. Nevertheless, the present effort is suitable for predictions of failure in engineering practice.     

Out-of-plane dual flexure MEMS piezoresistive accelerometer with low cross axis sensitivity

Microsystem Technologies - Accelerometers are one of the widely explored microsensors with many transduction mechanisms. One of the primary concerns with piezoresistive microaccelerometers is their...     

Triple diffusive flow of nanofluid with buoyancy forces and nonlinear thermal radiation over a horizontal plate

The present attempt is made to elaborate the features of triple diffusive convective flow of an incompressible nanoliquid induced by horizontal surface under buoyancy forces. The effect of nonlinear thermal radiation is taken into account. Heat flux model of radiation is formulated through Rosseland's approximation. The radiation phenomenon plays a key role in modern solar energy equipment's. The nondimensional variables are introduced to convert the dimensional mathematical expressions into dimensionless single independent variable. Numerical scheme is developed to obtain the solution of mathematical model. The importance of controlling constraints on flow quantities are characterized through plots. The quantities of engineering importance are computed and elaborated graphically. It is noticed that the presence of salts and nanoparticles enhance the thermal performance of base liquid. The liquid temperature and its relevant thickness of thermal layer improved significantly with an increment in the values of radiative parameter. The larger values of parameters of Brownian motion and thermophoretic correspond to higher temperature profiles.     

Conjugate natural convection in a fluid-saturated porous enclosure with two solid vertical partitions

Conjugate natural convection in a fluid-saturated square porous enclosure with two solid vertical partitions of finite and equal thickness equispaced from center of enclosure is investigated in this paper. The primary objective is to attenuate the Nusselt number (Nu) and hence the heat transfer rate across a differentially heated enclosure. Darcy's model is considered. Numerical computation is performed using successive accelerated replacement and explicit scheme. Partition ratio, partition length, thermal conductivity ratio, and modified Rayleigh number are the parameters under study. Fluid flow is analyzed by observing transient changes of streamlines and isotherms for partition length 0.3-1, thermal conductivity ratio 0.5-2, partition ratio 0.1-0.3 and modified Rayleigh number 100 and 1000 where partition ratio is the ratio of distance between center of enclosure and either of the partition center to the total length of the enclosure; while Nusselt number is calculated to estimate the heat transfer rate for each configuration. It is found that, employing a solid partition within the enclosure most definitely reduces the Nusselt number. The drop in Nusselt number is more for partition length 0-0.6 after which it does show a drop in Nu but only very subtle. Further, Nu is the least for partition ratio 0.2. Also, Nusselt number is proportional to thermal conductivity ratio which is the ratio of thermal conductivity of solid to porous medium.