Tungsten current price was transformed yearly to its constant price since 1900, which is roughly decomposed into four components as trend, cycle, impact and random. The core prices, consisting of the trend and the cyc...Tungsten current price was transformed yearly to its constant price since 1900, which is roughly decomposed into four components as trend, cycle, impact and random. The core prices, consisting of the trend and the cycle, present regularities that a long-run cycle is embedded within two major cycles, and major cycle is composed of low-price period and high-price period, along with the rapid rise into a tower, and along with deep down into next trough; three sharply upward shocks occur by the events in a tower. Fluctuations in prices trend to slow cycles and expand the bands. It can be expected that tungsten price will highly stand over 17 a, and is is a advice that reducing production and restricting export maybe maintain a high price level.展开更多
As one of the largest enterprises in China, Zhongyuan Petroleum Exploration Bureau. Sinopec (ZPEB) has become a medium-sized onshore oilfield with its exploration and development for more than thirty years. Its annu...As one of the largest enterprises in China, Zhongyuan Petroleum Exploration Bureau. Sinopec (ZPEB) has become a medium-sized onshore oilfield with its exploration and development for more than thirty years. Its annual output with crude oil of several milliontons and natnral gas of several billion cubicmeters has been kept for two decades.展开更多
基金Project(2013ZK2001)supported by the Major Soft Science Program of Hunan Provice,ChinaProjects(1382ZD024,13BGL105)supported by the National Social Science Foundation of China
文摘Tungsten current price was transformed yearly to its constant price since 1900, which is roughly decomposed into four components as trend, cycle, impact and random. The core prices, consisting of the trend and the cycle, present regularities that a long-run cycle is embedded within two major cycles, and major cycle is composed of low-price period and high-price period, along with the rapid rise into a tower, and along with deep down into next trough; three sharply upward shocks occur by the events in a tower. Fluctuations in prices trend to slow cycles and expand the bands. It can be expected that tungsten price will highly stand over 17 a, and is is a advice that reducing production and restricting export maybe maintain a high price level.
文摘As one of the largest enterprises in China, Zhongyuan Petroleum Exploration Bureau. Sinopec (ZPEB) has become a medium-sized onshore oilfield with its exploration and development for more than thirty years. Its annual output with crude oil of several milliontons and natnral gas of several billion cubicmeters has been kept for two decades.