提出了一种基于m次重启的简化广义最小残差法(simpler generalized minimal residual algorithm of m times restart,SGMRES(m))的电力系统暂态稳定仿真新算法,即采用SGMRES(m)方法对暂态稳定仿真中形成的线性方程组进行求解,通过修正...提出了一种基于m次重启的简化广义最小残差法(simpler generalized minimal residual algorithm of m times restart,SGMRES(m))的电力系统暂态稳定仿真新算法,即采用SGMRES(m)方法对暂态稳定仿真中形成的线性方程组进行求解,通过修正标准正交基的生成过程,使得m阶上Hessenberg矩阵成为上三角矩阵。这样,只要通过简单的上三角线性方程组的求解即可求得解的修正量,避免了求解广义最小残差法每次迭代中的最小二乘问题,从而有效地减少了计算量。为进一步加快计算速度,文中算法进一步结合了伪牛顿策略和不完全LU预处理技术。多个算例的计算结果表明,所提出方法是有效的。展开更多
This paper investigates the MED （Minimum Entransy Dissipation） optimization of heat transfer processes with the generalized heat transfer law q ∝ （A（T^n））m. For the fixed amount of heat transfer, the optimal te...This paper investigates the MED （Minimum Entransy Dissipation） optimization of heat transfer processes with the generalized heat transfer law q ∝ （A（T^n））m. For the fixed amount of heat transfer, the optimal temperature paths for the MED are obtained The results show that the strategy of the MED with generalized convective law q ∝ （△T）^m is that the temperature difference keeps constant, which is in accordance with the famous temperature-difference-field uniformity principle, while the strategy of the MED with linear phenomenological law q ∝ A（T^-1） is that the temperature ratio keeps constant. For special cases with Dulong-Petit law q ∝ （△T）^1.25 and an imaginary complex law q ∝ （△（T^4））^1.25, numerical examples are provided and further compared with the strategies of the MEG （Minimum Entropy Generation）, CHF （Constant Heat Flux） and CRT （Constant Reservoir Temperature） operations. Besides, influences of the change of the heat transfer amount on the optimization results with various heat resistance models are discussed in detail.展开更多
In this article, we apply the Generalized Uncertainty Principle （GUP）, which is consistent with quantum gravity theories to an elementary particle in a finite potential well, and study the quantum behavior in this s...In this article, we apply the Generalized Uncertainty Principle （GUP）, which is consistent with quantum gravity theories to an elementary particle in a finite potential well, and study the quantum behavior in this system. The generalized Hamiltonian contains two additional terms, which are proportional to ap3 （the result of the maximum momentum assumption） and a2p4 （the result of the minimum length assumption）, where a - 1/MpIc is the GUP parameter. On the basis of the work by Ali et al., we solve the generaiized Schrodinger equation which is extended to include the a2 correction term, and find that the length L of the finite potentiai well must be quantized. Then a generalization to the double-square-well potential is discussed. The result shows that all the measurable lengths especially the distance between the two potential wells are quantized in units of aolp1 in GUP scenario.展开更多
文摘提出了一种基于m次重启的简化广义最小残差法(simpler generalized minimal residual algorithm of m times restart,SGMRES(m))的电力系统暂态稳定仿真新算法,即采用SGMRES(m)方法对暂态稳定仿真中形成的线性方程组进行求解,通过修正标准正交基的生成过程,使得m阶上Hessenberg矩阵成为上三角矩阵。这样,只要通过简单的上三角线性方程组的求解即可求得解的修正量,避免了求解广义最小残差法每次迭代中的最小二乘问题,从而有效地减少了计算量。为进一步加快计算速度,文中算法进一步结合了伪牛顿策略和不完全LU预处理技术。多个算例的计算结果表明,所提出方法是有效的。
基金supported by the National Natural Science Foundation of China(Grant Nos.51576207,51356001&51579244)
文摘This paper investigates the MED （Minimum Entransy Dissipation） optimization of heat transfer processes with the generalized heat transfer law q ∝ （A（T^n））m. For the fixed amount of heat transfer, the optimal temperature paths for the MED are obtained The results show that the strategy of the MED with generalized convective law q ∝ （△T）^m is that the temperature difference keeps constant, which is in accordance with the famous temperature-difference-field uniformity principle, while the strategy of the MED with linear phenomenological law q ∝ A（T^-1） is that the temperature ratio keeps constant. For special cases with Dulong-Petit law q ∝ （△T）^1.25 and an imaginary complex law q ∝ （△（T^4））^1.25, numerical examples are provided and further compared with the strategies of the MEG （Minimum Entropy Generation）, CHF （Constant Heat Flux） and CRT （Constant Reservoir Temperature） operations. Besides, influences of the change of the heat transfer amount on the optimization results with various heat resistance models are discussed in detail.
基金Supported by National Natural Science Foundation of China under Grant Nos.10865003 and 11464005
文摘In this article, we apply the Generalized Uncertainty Principle （GUP）, which is consistent with quantum gravity theories to an elementary particle in a finite potential well, and study the quantum behavior in this system. The generalized Hamiltonian contains two additional terms, which are proportional to ap3 （the result of the maximum momentum assumption） and a2p4 （the result of the minimum length assumption）, where a - 1/MpIc is the GUP parameter. On the basis of the work by Ali et al., we solve the generaiized Schrodinger equation which is extended to include the a2 correction term, and find that the length L of the finite potentiai well must be quantized. Then a generalization to the double-square-well potential is discussed. The result shows that all the measurable lengths especially the distance between the two potential wells are quantized in units of aolp1 in GUP scenario.
