Pulsar timing data used to provide upper limits on a possible stochastic gravitational wave background (SGWB). However, the NANOGrav Collaboration has recently reported strong evidence for common-spectrum process, which we interpret as SGWB in framework of cosmic strings. The signal would correspond string tension $G\mu \in (4 \times 10^{-11}, 10^{-10}) $ at 68% confidence level, with different...

In this work a new resistance model has been presented based on that of Henis-Tripodi which can be used for interpretation of gas permeation data in composite and asymmetric membranes. In contrast to the previous works, in this model the fraction of the support layer surface that includes the pores filled with coating material has been taken into account. The influences of the filled pores on s...