Interacting open p-branes

The Kalb-Ramond action, derived for interacting strings through an action-at-a-distance force, is generalized to the case of interacting p-dimensional objects (p-branes) in D-dimensional space-time. The open p-brane version of the theory is especially taken up. On account of the existence of their boundary surface, the fields mediating interactions between open p-branes are obtained as massive gauge fields, quite in contrast to massless gauge ones for closed p-branes.Comment: 10 pages, LaTe

Kalb-Ramond interaction for a closed p-brane

The Kalb-Ramond action for an interacting string is generalized to the case of a high-dimensional object (p-brane). The interaction is found to be mediated by a gauge boson of a completely antisymmetric tensor of rank $p+1$.Comment: 7 page

Seafloor crustal deformation data along the subduction zones around Japan obtained by GNSS-A observations

Crustal deformation data obtained by geodetic observation networks are foundations in the fields of geodesy and seismology. These data are essential for understanding plate motion and earthquake sources and for simulating earthquake and tsunami disasters. Although relatively scarce, seafloor geodetic data are particularly important for monitoring the behaviour of undersea interplate boundary regions. Since the mid-1990s, we have been developing the combined Global Navigation Satellite System-Acoustic ranging (GNSS-A) technique for realizing seafloor geodesy. This technique allows us to collect time series of seafloor crustal deformation. Our published data can be used to investigate several seismological phenomena along the subduction zones around Japan, namely the Nankai Trough, Sagami Trough and Japan Trench. These regions are globally important places in geodesy and seismology and are also suitable for comparison with other geophysical datasets. Our intention is for these data to promote further understanding of megathrust zones.Comment: 16 pages, 6 figures, 4 table

Effects of Ground Improvement and Armored Embankment to the Displacements of the Seawalls and Back Fill During Earthquake

Large shaking table tests of the caisson type seawalls under various conditions were conducted in order to investigate the effects of the armored embankment and the improvement of sandy seabed and backfill by densification to the deformation of the seawalls during earthquake. Main results obtained from the shaking table tests were as follows : (1) Seaward horizontal displacement and tilting of the caisson were drastically reduced by the existence of the armored embankment in front of the caisson. (2) Improvement of the sandy seabed by densification method just under the rubble mound was much effective to reduction of the displacements of the caisson. (3) It was possible that the lateral movement of the liquefied backfill was reduced by the improvement of a part of the backfill just behind the caisson even though without the armored embankment in front of the caisson