Limited Production Policy Becomes Clear And Acute Shortages Of Alumina Exceed Expectations

As the macroeconomic situation is still difficult and there is no substantial stimulus prompted by news,the aluminum prices have fluctuated widely between 16,000-17,000 yuan/ton.Recently,Henan Province announced limited production across the province during the heating season and the Ministry of Environmental Protection also declared that30%limited production during the heating season will not overlap the policy of

Forecasting of China's natural gas production and its policy implications

With the vigorous promotion of energy conservation and implementation of clean energy strategies,China＇s natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important role in China＇s energy structure.This paper uses a Generalized Weng model to forecast Chinese regional natural gas production,where accuracy and reasonableness compared with other predictions are enhanced by taking remaining estimated recoverable resources as a criterion.The forecast shows that China＇s natural gas production will maintain a rapid growth with peak gas of 323 billion cubic meters a year coming in 2036;in 2020,natural gas production will surpass that of oil to become a more important source of energy.Natural gas will play an important role in optimizing China＇s energy consumption structure and will be a strategic replacement of oil.This will require that exploration and development of conventional natural gas is highly valued and its industrial development to be reasonably planned.As well,full use should be made of domestic and international markets.Initiative should also be taken in the exploration and development of unconventional and deepwater gas,which shall form a complement to the development of China＇s conventional natural gas industry.

Optimal production lot size with process deterioration under an extended inspection policy

A mathematical model to determine the optimal production lot size for a deteriorating production system under an extended product inspection policy is developed. The last-K product inspection policy is considered so that the nonconforming items can be reduced, under which the last K products in a production lot are inspected and the nonconforming items from those inspected are reworked. Consider that the products produced towards the end of a production lot are more likely to be nonconforming, is proposed an extended product inspection policy for a deteriorating production system. That is, in a production lot, product inspections are performed among the middle K1 items and after inspections, all of the last K2 products are directly reworked without inspections. Our objective here is the joint optimization of the production lot size and the corresponding extended inspection policy such that the expected total cost per unit time is minimized. Since there is no closed form expression for our optimal policy, the existence for the optimal production inspection policy and an upper bound for the optimal lot size are obtained. Furthermore, an efficient solution procedure is provided to search for the optimal policy. Finally, numerical examples are given to illustrate the proposed model and indicate that the expected total cost per unit time of our product inspection model is less than that of the last-K inspection policy.

Where is the future of China's biogas? Review, forecast,and policy implications

This paper discusses the history and present status of different categories of biogas production in China,most of which are classified into rural household production,agriculture-based engineering production,and industry-based engineering production.To evaluate the future biogas production of China,five models including the Hubbert model,the Weibull model,the generalized Weng model,the H-C-Z model,and the Grey model are applied to analyze and forecast the biogas production of each province and the entire country.It is proved that those models which originated from oil research can also be applied to other energy sources.The simulation results reveal that China＇s total biogas production is unlikely to keep on a fast-growing trend in the next few years,mainly due to a recent decrease in rural household production,and this greatly differs from the previous goal set by the official department.In addition,China＇s biogas production will present a more uneven pattern among regions in the future.This paper will give preliminary explanation for the regional difference of the three biogas sectors and propose some recommendations for instituting corresponding policies and strategies to promote the development of the biogas industry in China.