Alon@mekkaokereke @14mission Or why the tunnel boring is the most solved part of urban infrastructure tunnel construction. The US has a huge cost premium, but little of it is the tunnel boring (except in San Jose, which is doing stupid things with the BART subway) - the premium is mostly in everything else, like ancillary structures, systems, junctions, subway stations, etc.
GNU social JP is a social network, courtesy of GNU social JP管理人. It runs on GNU social, version 2.0.2-dev, available under the GNU Affero General Public License.
All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.