Hi Marco, great! You should send a link to the appropriate ministeries. Regards Hans

Dear Kotaro,

thank you very much for your reply. I really like your posts and the tricks you teach there have become very useful to me. Thanks a lot!

Unfortunately, I have not yet seen a data file of the Japanese bridges, but found that there are about 700000 bridges (of length 2 m or more) in Japan. about 50% of the bridges appear to be more than 50 years old. I am also not sure how large the effect of potential earth quakes is on the bridges. This might lead to additional tear and wear.

There is a non-Japan related paper that investigates bridges and they use a machine learning approach to analyse the quality/state of bridges. They use sensor data that will be difficult to get, but I would love to try something like that, if I could lay hands on data like that.

I see that Fujitsu use deep learning to study the internal damage to bridge infrastructure. They use data from RAIMS (Research Association for Infrastructure Monitoring System). Unfortunately, I get lost very quickly, because many links lead to websites in Japanese and I am out of my depth there.

Best wishes from Aberdeen,

Marco

Dear Henrik,

thank you again for your kind words!

Yes, you are quite right: it is strange that we see such great differences between the different states. I have tried to find out how these things are paid for, and it seems to be quite complicated. I couldn't find any reliable data about the contributions of states, local communities, and federal government. It appears that some states do not "request" all the money of the federal government for infrastructure, because they have to co-finance. It appears that some only request a tiny fraction of the available budget.

I must admit that I have no idea how this works. Here are some vaguely related ideas: I have found some data on the total length of streets in the different states. That might also eat-up some of the available funds. Here is a BarChart of the number of bridges in the different states (apparently including jointly owned/managed bridges):

weltData = Import["/Users/thiel/Desktop/DIE WELT_ Zustand der Fernstraßenbrücken - 
Daten.tsv"];

BarChart[#[[All, 2]], ChartLabels -> ( Rotate[#, Pi/2] & /@ #[[All, 1]]), AspectRatio -> 1/4, LabelStyle -> Directive[Bold, 12]] &@Reverse@SortBy[Tally[weltData[[2 ;;, 3]]], Last]

Perhaps we can find data telling us whether the money invested into/given to the states is roughly proportional to the number of bridges?

It would be quite interesting to see this, I guess. Also, these infrastructure funds might be spent for other types of infrastructure (railways etc). It would be nice to see whether the decisions taken on where to invest explain the differences.

I find it a bit frightening how little I know about these things... If there are others like me out there, the Wolfram Language might help to shed some light on this.

Best wishes,

Marco