8,612 research outputs found
Piezoelectric and pyroelectric effects of a crystalline polymer
Polyvinylidene flouride (PVDF) is a crystalline polymer to both piezoelectric and pyroelectric nature. Piezoelectricity produces electrical signals when mechanically deformed, and pyroelectricity is the electrical polarization induced by thermal absorption in crystals. To demonstrate the piezoelectric effect PVDF is subjected to impact loads which produce electrical charges proportional to mechanical stresses. A heat source was used to demonstrate the pyroelectric nature of PVDF. The rise in temperature due to absorbed energy by the polymer produces electrical output. The qualitative test results obtained are graphically reproduced
Parameter Estimates of General Failure Rate Model: A Bayesian Approach
The failure rate function plays an important role in studying the lifetime
distributions in reliability theory and life testing models. A study of the
general failure rate model , under squared error loss
function taking and independent exponential random variables has been
analyzed in the literature. In this article, we consider and not
necessarily independent. The estimates of the parameters and under
squared error loss, linex loss and entropy loss functions are obtained here
- …