Fair exchange protocols allow both or neither of two parties to obtain the other’s items, and this property is essential in e-commerce. In this paper, we construct an optimistic fair exchange protocol that is applicable to any digital signature by prescribing three forms of signatures, namely presignature, post-signature and notarised signature. We set an expiration date for presignature, and t...

The aims of this study are: To find out how the influence CSRD, institutional ownership, leverage and asset growth on firm value in construction, property real estate companies listed Indonesian stock exchange. This research design includes type associative research, namely that seeks or relationship two more variables. Based data, is classified as quantitative uses numbers. Simultaneously simu...

The porous mixed oxide SiO2/TiO2/Sb2O5 obtained by the sol-gel processing method presented a good ion exchange property and a high exchange capacity towards the Li+, Na+ and K+ ions. In the H+/ M+ ion exchange process, the H+ / Na+ could be described as presenting an ideal character. The ion exchange equilibria of Li+ and K+ were quantitatively described with the help of the model of fixed tetr...

Measurements of coherent electron spin dynamics in Ga1-xMnxAs/Al0.4Ga0.6As quantum wells with 0.0006%<x<0.03% show an antiferromagnetic (negative) exchange between s-like conduction band electrons and electrons localized in the d shell of the Mn2+ impurities. The magnitude of the s-d exchange parameter, N0alpha, varies as a function of well width indicative of a large and negative contribution ...