This paper gives a necessary and sufficient condition on the existence and uniquenessof 2π-periodic solution of Duffing equation d^2x/dt^2+g(x)=p(t) (=P(t+2π)).
1 The Investment Situation of Auto Industrial Powers in China Chinese auto industry has made rapid progress after development of 50 years. However it is still at the infant stage. The government has to protect it by m...1 The Investment Situation of Auto Industrial Powers in China Chinese auto industry has made rapid progress after development of 50 years. However it is still at the infant stage. The government has to protect it by means of long-term, rigorous tariff and non-tariff devices. But the U.S., Japan and other European countries have made investment into Chinese auto industry, because it’s incontrovertible that China is the most potential market in the world.展开更多
文摘This paper gives a necessary and sufficient condition on the existence and uniquenessof 2π-periodic solution of Duffing equation d^2x/dt^2+g(x)=p(t) (=P(t+2π)).
文摘1 The Investment Situation of Auto Industrial Powers in China Chinese auto industry has made rapid progress after development of 50 years. However it is still at the infant stage. The government has to protect it by means of long-term, rigorous tariff and non-tariff devices. But the U.S., Japan and other European countries have made investment into Chinese auto industry, because it’s incontrovertible that China is the most potential market in the world.
