And, in any case, by what sort of accounting was it determined that the method was too expensive?
Agnese Parronchi, the experienced restorer first hired to clean the statue, resigned in April, charging that the officially approved method was too harsh and could cause damage.
Fog has also been cleared by spreading chemicals from a plane that turned some fog into rain, but this method was too costly.
But after having invested almost $2 billion in the technology, the United States Enrichment Corporation, America's privatized nuclear fuel provider, abandoned the technology last year, saying the method was too expensive to commercialize and would probably always be so.
Sarah Haider, head of client engineering at Periscope, said some common moderation techniques involved blacklisting certain words, but that that method was too crude and could not take the context of the conversation into account.
However, the surface roughness of porous silicon wall fabricated by electrochemical etching method was too high even existing bifurcation structure, which seriously restricts the application of electrochemical etching method used to fabricate silicon solid-state nanopore.
