In this paper,an oil well production scheduling problem for the light load oil well during petroleum field exploitation was studied.The oil well production scheduling was to determine the turn on/off status and oil fl...In this paper,an oil well production scheduling problem for the light load oil well during petroleum field exploitation was studied.The oil well production scheduling was to determine the turn on/off status and oil flow rates of the wells in a given oil reservoir,subject to a number of constraints such as minimum up/down time limits and well grouping.The problem was formulated as a mixed integer nonlinear programming model that minimized the total production operating cost and start-up cost.Due to the NP-hardness of the problem,an improved particle swarm optimization(PSO) algorithm with a new velocity updating formula was developed to solve the problem approximately.Computational experiments on randomly generated instances were carried out to evaluate the performance of the model and the algorithm's effectiveness.Compared with the commercial solver CPLEX,the improved PSO can obtain high-quality schedules within a much shorter running time for all the instances.展开更多
Atmospheric visibility impairment due to human activities is becoming increasingly significant in metropolitan 8henyang, China. In this study, hourly data of relevant factors throughout the year 2010 in Shenyang were ...Atmospheric visibility impairment due to human activities is becoming increasingly significant in metropolitan 8henyang, China. In this study, hourly data of relevant factors throughout the year 2010 in Shenyang were used to evaluate the local atmospheric extinction properties. The results show that the average coefficient of total extinction and aerosol single-scattering albedo in 2010 were 622.72 Mm^-1 and 0.87, respectively, values that are characteristic of the ＂municipal pollution type＂. Visibility is most impaired during winter and especially in January. The coefficient of total extinction exhibits a single daily cycle with a maximum at 5-6 am and a minimum at 3 pm. The mean extinction contributions of the constituents, from high to low, were particle scattering （87.49%）, particle absorption, gas absorption, and gas scattering. The extinction contribution of gas molecules was little more than 4.5%, far smaller than that of particles. Scattering by particles was the main contributor to extinction, especially in the morning and around midnight.展开更多
1 IntroductionIn our previous work,a systematical method for treating the elastic scattering ofcomposite particles was proposed.The constituents of the impinging and/or target parti-cles in question were considered to...1 IntroductionIn our previous work,a systematical method for treating the elastic scattering ofcomposite particles was proposed.The constituents of the impinging and/or target parti-cles in question were considered to be composed of only one kind of constituent by Ref.[1],but the constituents were considered to be composed of multiconstituents by Ref.[2].Themethod of finding analytical expression is simple and convenient.The Glauber theory isdeveloped and presented in a clear manner.But we have only calculated pp,(?)p and πpin both Refs.[1]and[2].According to quark model,proton consists of two u quarks and展开更多
基金Supported by National High Technology Research and Development Program of China(2013AA040704)the Fund for the National Natural Science Foundation of China(61374203)
文摘In this paper,an oil well production scheduling problem for the light load oil well during petroleum field exploitation was studied.The oil well production scheduling was to determine the turn on/off status and oil flow rates of the wells in a given oil reservoir,subject to a number of constraints such as minimum up/down time limits and well grouping.The problem was formulated as a mixed integer nonlinear programming model that minimized the total production operating cost and start-up cost.Due to the NP-hardness of the problem,an improved particle swarm optimization(PSO) algorithm with a new velocity updating formula was developed to solve the problem approximately.Computational experiments on randomly generated instances were carried out to evaluate the performance of the model and the algorithm's effectiveness.Compared with the commercial solver CPLEX,the improved PSO can obtain high-quality schedules within a much shorter running time for all the instances.
基金financially supported by the Basic Research and Service Fund Item of IAE(No.2013IAE-CMA05)the Integration and Application Item of Meteorological Key Technologies(No. CMAGJ2014M12)+3 种基金the National Science and Technology Pillar Program(No.2014BAC16B04)the Liaoning Province Key Technologies Program of China(No.2013229031)the Public Welfare Professional Item(Meteorology)(Nos.GYHY201406031 and 201206002)National Natural Science Foundation of China(Nos.40705037, 41375146,and 31270480)
文摘Atmospheric visibility impairment due to human activities is becoming increasingly significant in metropolitan 8henyang, China. In this study, hourly data of relevant factors throughout the year 2010 in Shenyang were used to evaluate the local atmospheric extinction properties. The results show that the average coefficient of total extinction and aerosol single-scattering albedo in 2010 were 622.72 Mm^-1 and 0.87, respectively, values that are characteristic of the ＂municipal pollution type＂. Visibility is most impaired during winter and especially in January. The coefficient of total extinction exhibits a single daily cycle with a maximum at 5-6 am and a minimum at 3 pm. The mean extinction contributions of the constituents, from high to low, were particle scattering （87.49%）, particle absorption, gas absorption, and gas scattering. The extinction contribution of gas molecules was little more than 4.5%, far smaller than that of particles. Scattering by particles was the main contributor to extinction, especially in the morning and around midnight.
基金Project supported in part by Fujian Provindal Science Foundation,China.
文摘1 IntroductionIn our previous work,a systematical method for treating the elastic scattering ofcomposite particles was proposed.The constituents of the impinging and/or target parti-cles in question were considered to be composed of only one kind of constituent by Ref.[1],but the constituents were considered to be composed of multiconstituents by Ref.[2].Themethod of finding analytical expression is simple and convenient.The Glauber theory isdeveloped and presented in a clear manner.But we have only calculated pp,(?)p and πpin both Refs.[1]and[2].According to quark model,proton consists of two u quarks and
