Precise leveling of the very long Qinling mountain tunnel

Tunnel Leveling, Depth, and Bridge Numbers

We use the theory of tunnel number 1 knots introduced in an earlier paper to strengthen the Tunnel Leveling Theorem of Goda, Scharlemann, and Thompson. This yields considerable information about bridge numbers of tunnel number 1 knots. In particular, we calculate the minimum bridge number of a knot as a function of the maximum depth invariant d of its tunnels. The growth of this value is on the...

Precise geodesy with the Very Long Baseline Array

We report on a program of geodetic measurements between 1994 and 2007 which used the Very Long Baseline Array and up to 10 globally distributed antennas. One of the goals of this program was to monitor positions of the array at a 1 millimeter level of accuracy and to tie the VLBA into the International Terrestrial Reference Frame. We describe the analysis of these data and report several intere...

Troposphere Modeling and Filtering for Precise GPS Leveling

00 8 Tunnel Leveling , Depth , and Bridge Numbers

We use the theory of tunnel number 1 knots introduced in [5] to strengthen the Tunnel Leveling Theorem of Goda, Scharlemann, and Thompson. This yields considerable information about bridge numbers of tunnel number 1 knots. In particular, we calculate the minimum bridge number of a knot as a function of the maximum depth invariant d of its tunnels. The growth of this value is on the order of (1 ...

Precise Long Tunnel Survey using the Riegl VMX-250 Mobile Laser Scanning System

Our company has been using the RIEGL VMX-250 since July 2010 in diverse scenarios, especially where data acquisition productivity is pertinent. In this presentation, we will be describing a long tunnel survey project. Spain has the longest high speed trail network in Europe. Recently, two parallel 25 km long tunnels were built and an accurate 3D survey was demanded by the Spanish authorities. A...