In the present electricity market, where renewable energy power plants have been included in the power systems, there is a lot of unpredictability in the demand and generation. There are many conventional and evolutio...In the present electricity market, where renewable energy power plants have been included in the power systems, there is a lot of unpredictability in the demand and generation. There are many conventional and evolutionary programming techniques used for solving the unit commitment （UC） problem. Dynamic programming （DP） is a conventional algorithm used to solve the deterministic problem. In this paper DP is used to solve the stochastic model of UC problem. The stochastic modeling for load and generation side has been formulated using an approximate state decision approach. The programs were developed in a MATLAB environment and were exten- sively tested for a four-unit eight-hour system. The results obtained from these techniques were validated with the available literature and outcome was good. The commitment is in such a way that the total cost is minimal. The novelty of this paper lies in the fact that DP is used for solving the stochastic UC problem.展开更多
This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) ...This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) that is fractional in time and homogeneous in space.展开更多
Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low fre- quencies, especially at ultra-low frequencies under conditions of different moisture conce...Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low fre- quencies, especially at ultra-low frequencies under conditions of different moisture concentrations and temperatures, which is recognized as the low frequency dispersion (LFD). In order to explain this dispersion, a new mechanism of dielectric response of LFD of oil-paper insula- tion is proposed. A simplified one-dimensional mathematical model of concentration polarization carrier caused by slow migration is developed and solved, which indicates that ion mobility is closely related to the size of gap and the adsorption capacity of cellulose molecu- lar chains to ions. A stochastic statistical model of the carrier mobility induced LFD is also developed. Moreover, actual tests under 50 °C and 2% moisture content were put forward, as well as simulations with according current waveforms. The simulation results agreed well with the experimental data in that concentration polarization of carriers caused by slow migration is the probable cause of low frequency dispersion of dielectric response for oil-paper insulation diagnosis.展开更多
研究了正、负两类顾客的离散时间Geo/Geo/1多重工作休假排队模型,并加入N策略和启动时间,负顾客不接受服务,并只起一对一抵消队首正接受服务的顾客的作用,即服从RCH(Remove customer from head)策略。使用拟生灭过程及矩阵几何解方法得...研究了正、负两类顾客的离散时间Geo/Geo/1多重工作休假排队模型,并加入N策略和启动时间,负顾客不接受服务,并只起一对一抵消队首正接受服务的顾客的作用,即服从RCH(Remove customer from head)策略。使用拟生灭过程及矩阵几何解方法得到队长的稳态分布,进一步得出了系统队长的随机分解的结果。展开更多
文摘In the present electricity market, where renewable energy power plants have been included in the power systems, there is a lot of unpredictability in the demand and generation. There are many conventional and evolutionary programming techniques used for solving the unit commitment （UC） problem. Dynamic programming （DP） is a conventional algorithm used to solve the deterministic problem. In this paper DP is used to solve the stochastic model of UC problem. The stochastic modeling for load and generation side has been formulated using an approximate state decision approach. The programs were developed in a MATLAB environment and were exten- sively tested for a four-unit eight-hour system. The results obtained from these techniques were validated with the available literature and outcome was good. The commitment is in such a way that the total cost is minimal. The novelty of this paper lies in the fact that DP is used for solving the stochastic UC problem.
基金Research partially supported by the “1000 Talents Plan” from Jilin University,Jilin Province and Chinese Governmentby the Simons Foundation(244767)
文摘This article establishes the precise asymptotics Eu^m(t, x)(t → ∞ or m → ∞) for the stochastic heat equation ?u/?t(t, x) =1/2?u(t, x) + u(t, x)(t, x)?W/?t(t, x) with the time-derivative Gaussian noise W?/?t(t, x) that is fractional in time and homogeneous in space.
基金Project supported by National Nature Science Foundation of China （51107105）, Sichuan Science Fund for Young Scholars （2011JQ0009）.
文摘Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low fre- quencies, especially at ultra-low frequencies under conditions of different moisture concentrations and temperatures, which is recognized as the low frequency dispersion (LFD). In order to explain this dispersion, a new mechanism of dielectric response of LFD of oil-paper insula- tion is proposed. A simplified one-dimensional mathematical model of concentration polarization carrier caused by slow migration is developed and solved, which indicates that ion mobility is closely related to the size of gap and the adsorption capacity of cellulose molecu- lar chains to ions. A stochastic statistical model of the carrier mobility induced LFD is also developed. Moreover, actual tests under 50 °C and 2% moisture content were put forward, as well as simulations with according current waveforms. The simulation results agreed well with the experimental data in that concentration polarization of carriers caused by slow migration is the probable cause of low frequency dispersion of dielectric response for oil-paper insulation diagnosis.
文摘研究了正、负两类顾客的离散时间Geo/Geo/1多重工作休假排队模型,并加入N策略和启动时间,负顾客不接受服务,并只起一对一抵消队首正接受服务的顾客的作用,即服从RCH(Remove customer from head)策略。使用拟生灭过程及矩阵几何解方法得到队长的稳态分布,进一步得出了系统队长的随机分解的结果。
