We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states...We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states is controlled by a short pulse, and the objective is to maximize the collective population on all excited states when we treat all of them as one level. Two cases of the systems are shown to be equivalent to effective two-level systems. When the pulse is weak, simple relations between the original systems and the reduced systems are obtained. When the pulse is strong, these relations are still available for pulses with only one frequency under the first-order approximation.展开更多
Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constrai...Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.展开更多
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.61074052 and No.61072032）. Herschel Rabitz acknowledges the support from Army Research Office （ARO）.
文摘We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states is controlled by a short pulse, and the objective is to maximize the collective population on all excited states when we treat all of them as one level. Two cases of the systems are shown to be equivalent to effective two-level systems. When the pulse is weak, simple relations between the original systems and the reduced systems are obtained. When the pulse is strong, these relations are still available for pulses with only one frequency under the first-order approximation.
基金The National Social Science Foundation of China(17CTY014).
文摘Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.
