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Interestingly the Japanese shinkansen system has seismic detectors all over the route. If there's enough activity detected then it can automatically stop all tr

Interestingly the Japanese shinkansen system has seismic detectors all over the route. If there's enough activity detected then it can automatically stop all trains. Clever stuff.

bamboozled 6y ago
I’d say this isn’t just clever, it’s absolutely necessary
kalleboo 6y ago
Japan as a country has seismic detectors all over. These are fed into a centralized earthquake early warning system that stops not only Shinkansen, but other trains, elevators, alerts surgeons in hospitals, sends out broadcast push notifications to phones, etc. The system is so fast that the notifications arrive to areas beyond the epicenter before the seismic waves themselves, giving people and devices precious seconds to prepare [0] Compare the number of seismographs in Japan https://www.jma.go.jp/jma/en/Activities/image/earth-fig02.png https://www.jma.go.jp/jma/en/Activities/image/earth-fig02.pn... To California (only the green ones exist, blue are proposals) https://cdn.kqed.org/wp-content/uploads/sites/35/2018/10/CA_EERStation_Status_September2018.jpg https://cdn.kqed.org/wp-content/uploads/sites/35/2018/10/CA_... [0] https://en.wikipedia.org/wiki/Earthquake_Early_Warning_(Japan) https://en.wikipedia.org/wiki/Earthquake_Early_Warning_(Japa...
- JoshuaDavid 6y ago
  For reference, here are the two maps superimposed on one another at the same scale (again, only the green markers are real markers on the California map). [1] https://ibb.co/x5tLwHf https://ibb.co/x5tLwHf
- shalmanese 6y ago
  > The system is so fast that the notifications arrive to areas beyond the epicenter before the seismic waves themselves, giving people and devices precious seconds to prepare TBF, even Twitter is a "notification system fast enough to arrive in areas before the seismic wave". There's been numerous reports of twitter users seeing tweets about an earthquake before experiencing the shock wave. Building a system that can do that reliably is an engineering feat but we're talking on the order of 10s of seconds, not milliseconds.

Interestingly the Japanese shinkansen system has seismic detectors all over the route. If there's enough activity detected then it can automatically stop all trains. Clever stuff.

bamboozled 6y ago

I’d say this isn’t just clever, it’s absolutely necessary

kalleboo 6y ago

Japan as a country has seismic detectors all over. These are fed into a centralized earthquake early warning system that stops not only Shinkansen, but other trains, elevators, alerts surgeons in hospitals, sends out broadcast push notifications to phones, etc. The system is so fast that the notifications arrive to areas beyond the epicenter before the seismic waves themselves, giving people and devices precious seconds to prepare [0] Compare the number of seismographs in Japan https://www.jma.go.jp/jma/en/Activities/image/earth-fig02.png https://www.jma.go.jp/jma/en/Activities/image/earth-fig02.pn... To California (only the green ones exist, blue are proposals) https://cdn.kqed.org/wp-content/uploads/sites/35/2018/10/CA_EERStation_Status_September2018.jpg https://cdn.kqed.org/wp-content/uploads/sites/35/2018/10/CA_... [0] https://en.wikipedia.org/wiki/Earthquake_Early_Warning_(Japan) https://en.wikipedia.org/wiki/Earthquake_Early_Warning_(Japa...

JoshuaDavid 6y ago
For reference, here are the two maps superimposed on one another at the same scale (again, only the green markers are real markers on the California map). [1] https://ibb.co/x5tLwHf https://ibb.co/x5tLwHf
shalmanese 6y ago
> The system is so fast that the notifications arrive to areas beyond the epicenter before the seismic waves themselves, giving people and devices precious seconds to prepare TBF, even Twitter is a "notification system fast enough to arrive in areas before the seismic wave". There's been numerous reports of twitter users seeing tweets about an earthquake before experiencing the shock wave. Building a system that can do that reliably is an engineering feat but we're talking on the order of 10s of seconds, not milliseconds.