The minimum independent dominance set(MIDS)problem is an important version of the dominating set with some other applications.In this work,we present an improved master-apprentice evolutionary algorithm for solving th...The minimum independent dominance set(MIDS)problem is an important version of the dominating set with some other applications.In this work,we present an improved master-apprentice evolutionary algorithm for solving the MIDS problem based on a path-breaking strategy called MAE-PB.The proposed MAE-PB algorithm combines a construction function for the initial solution generation and candidate solution restarting.It is a multiple neighborhood-based local search algorithm that improves the quality of the solution using a path-breaking strategy for solution recombination based on master and apprentice solutions and a perturbation strategy for disturbing the solution when the algorithm cannot improve the solution quality within a certain number of steps.We show the competitiveness of the MAE-PB algorithm by presenting the computational results on classical benchmarks from the literature and a suite of massive graphs from real-world applications.The results show that the MAE-PB algorithm achieves high performance.In particular,for the classical benchmarks,the MAE-PB algorithm obtains the best-known results for seven instances,whereas for several massive graphs,it improves the best-known results for 62 instances.We investigate the proposed key ingredients to determine their impact on the performance of the proposed algorithm.展开更多
A Mg-2Zn-2Gd alloy subjected to a cross rolling and annealing often has a texture with c-axes of grains evenly distributing on a circle approximately 40°away from the normal direction(ND),which can completely rem...A Mg-2Zn-2Gd alloy subjected to a cross rolling and annealing often has a texture with c-axes of grains evenly distributing on a circle approximately 40°away from the normal direction(ND),which can completely remove the planar mechanical anisotropy.The texture memory effect and planar mechanical anisotropy of such a cross-rolled plate after an unidirectional rolling and subsequent annealing were systematically investigated.The results show that the circle-shaped texture is partially retained after the unidirectional rolling and annealing,with basal poles evenly distributing on an ellipse approximately 30°–40°away from the ND.This small texture difference will lead to quite different mechanical anisotropies between the two plates,namely,a quite low anisotropy of yield strength between the rolling direction(RD)and transverse direction(TD)before the unidirectional rolling,in contrast to an obvious mechanical anisotropy after unidirectional rolling.A quantitative calculation shows that tension along the RD of the plate after the unidirectional rolling will activate a much higher fraction of prismatic slip than tension along the TD.The much higher critical resolved shear stress for prismatic slip than that for basal slip or{10■2}twinning accounts for the much higher yield strength of TD tension than that of RDtension.The mechanisms for texture evolution during the unidirectional rolling and annealing were also discussed.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.61806050,61972063,61976050)the Fundamental Research Funds for the Central Universities(2412020FZ030,2412019ZD013,2412019FZ051)Jilin Science and Technology Association(QT202005).
文摘The minimum independent dominance set(MIDS)problem is an important version of the dominating set with some other applications.In this work,we present an improved master-apprentice evolutionary algorithm for solving the MIDS problem based on a path-breaking strategy called MAE-PB.The proposed MAE-PB algorithm combines a construction function for the initial solution generation and candidate solution restarting.It is a multiple neighborhood-based local search algorithm that improves the quality of the solution using a path-breaking strategy for solution recombination based on master and apprentice solutions and a perturbation strategy for disturbing the solution when the algorithm cannot improve the solution quality within a certain number of steps.We show the competitiveness of the MAE-PB algorithm by presenting the computational results on classical benchmarks from the literature and a suite of massive graphs from real-world applications.The results show that the MAE-PB algorithm achieves high performance.In particular,for the classical benchmarks,the MAE-PB algorithm obtains the best-known results for seven instances,whereas for several massive graphs,it improves the best-known results for 62 instances.We investigate the proposed key ingredients to determine their impact on the performance of the proposed algorithm.
基金supported financially by the National Natural Science Foundation of China(Nos.51871032 and 51421001)the Fundamental Research Funds for the Central Universities(No.2019CDQYCL032).
文摘A Mg-2Zn-2Gd alloy subjected to a cross rolling and annealing often has a texture with c-axes of grains evenly distributing on a circle approximately 40°away from the normal direction(ND),which can completely remove the planar mechanical anisotropy.The texture memory effect and planar mechanical anisotropy of such a cross-rolled plate after an unidirectional rolling and subsequent annealing were systematically investigated.The results show that the circle-shaped texture is partially retained after the unidirectional rolling and annealing,with basal poles evenly distributing on an ellipse approximately 30°–40°away from the ND.This small texture difference will lead to quite different mechanical anisotropies between the two plates,namely,a quite low anisotropy of yield strength between the rolling direction(RD)and transverse direction(TD)before the unidirectional rolling,in contrast to an obvious mechanical anisotropy after unidirectional rolling.A quantitative calculation shows that tension along the RD of the plate after the unidirectional rolling will activate a much higher fraction of prismatic slip than tension along the TD.The much higher critical resolved shear stress for prismatic slip than that for basal slip or{10■2}twinning accounts for the much higher yield strength of TD tension than that of RDtension.The mechanisms for texture evolution during the unidirectional rolling and annealing were also discussed.
