Impact of directional illumination control parameters on seismic signals
To improve quality of seismic signals, DICT (directional illumination control technique) of DVAS (the distributed vibrator array system) is developed. It explains DICT theory in seismic wave domain and states why DVAS can generate directional seismic wave with DICT. The property of directional seismic wave can be described with directional factor. From directional factor, some control parameters such as amount of vibrators, arrangement of DVAS and delay time play an important role in seismic wave directivity and reflected waves' SNR (signal signal-to-noise ratio). To study parameters of directional illumination system, receiving signals are simulated by numerical method. The results show that reflected wave' SNR can be improved with more vibrators and small space between adjacent source in the same line. When the amount and space of source are settled down, a long delay time can increase reflected wave' SNR in shallow lays and a short delay time can boost signal SNR in deep lays. It concludes that DICT is a better control method to achieve high SNR signals with proper parameters. Furthermore, it offers some rules on how to determine parameters.
Detection performance of a diffusive wave phased array.
Diffusive wave phased arrays have been demonstrated to be a sensitive method of detecting inhomogeneities embedded in heavily scattering media. However, the increase in sensitivity is coupled with an increase in noise, so that the optimum performance may not be obtained when the sources are modulated in antiphase. The performance of a range of configurations in the presence of Gaussian noise is investigated by using probabilistic detection theory. A model of diffusive wave propagation through scattering media is used to demonstrate that the phase performance can be improved by controlling the relative phase difference between the two sources. However, the best performance is obtained by using the amplitude response of a single source system. The major benefit of a phased array system is therefore the rejection of common systematic noise.
Two weddings and a lawsuit: Marriage litigation in fourteenth-century Portugal
Based on one of the few surviving records of marriage cases brought before
 ecclesiastical courts in fourteenth-century Portugal, this article offers a rare
 glimpse of marriage practice in a small village in a remote corner of Western Europe
 and the complex ties that bound its inhabitants and which secular and ecclesiastical
 authorities sought to regulate. Clear parallels can be drawn with the patterns of
 marriage litigation observed in England and Northern France, but evidence also
 suggests that royal legislation played an important part in the resolution of marital
 disputes and in the shaping of conjugal behaviour.