Meanwhile, prices of many Japanese imports - from baby formula to lotions to fish - have surged due to a supply crunch following the disaster, state media reports said.
And the three optimization problems are solved respectively by the conjugate gradient method, the adaptive bivariate shrinking and the gradient descent method.
Technological change may well reinforce that shift: the skills that complement computers, from management knowhow to creativity, do not necessarily decline with age.
But lately Japan has been forced to rethink that, prompted by a declining market for passenger and freight traffic at home, as well as a flurry of overseas opportunities.
Japan's declining birth rate means that by 2015 more than one in four Japanese will be 65 or over, while the working population is forecast to shrink almost 10 per cent by 2030.
Long run economic constraints include declining oil production and exports and pressure on water supplies caused by rapid population growth, industrial expansion, and increased water pollution.
The slump in interest has been partly caused by declining skills among young people and the rise in popularity of ready-to-assemble flat-pack furniture .
Although the Danish shipping line transported more containers, this was not enough to offset the impact from declining freight rates caused by an excess of capacity.