The notions of metric sparsification property and finite decomposition complexity are recently introduced in metric geometry to study the coarse Novikov conjecture and the stable Borel conjecture. In this paper, it is...The notions of metric sparsification property and finite decomposition complexity are recently introduced in metric geometry to study the coarse Novikov conjecture and the stable Borel conjecture. In this paper, it is proved that a metric space X has finite decomposition complexity with respect to metric sparsification property if and only if X itself has metric sparsification property. As a consequence, the authors obtain an alternative proof of a very recent result by Guentner, Tessera and Yu that all countable linear groups have the metric sparsification property and hence the operator norm localization property.展开更多
The integrated power system(IPS) is a foundation of all-electrical ships and vessels. The stability of IPS becomes a prerequisite of complicated cruise tasks. Thus, advanced stability analysis and regulation methods f...The integrated power system(IPS) is a foundation of all-electrical ships and vessels. The stability of IPS becomes a prerequisite of complicated cruise tasks. Thus, advanced stability analysis and regulation methods for IPS are of great importance. In this paper, a novel method is proposed for analyzing and enhancing transient stability of IPS, which is regarded as a cyber-physical system comprising of subsystems and connections. Criterions for determining input-output stability of such a system are firstly derived. Then, the stability analysis of IPS can be performed in the following two steps: 1) evaluating local input-output stability features of each subsystem independently through simulations. 2) Checking stability criterions with system topology and subsystem stability features. Moreover, synthetic approaches are proposed for stabilization and stability enhancement of IPS. To avoid system in-stability after major failures or topology changes, the optimal emergency control is performed to reconfigure subsystems. The other optimal regulation is used to strengthen system stability by adjusting subsystems' control parameters during normal operation conditions. Case studies on a typical IPS validate the proposed stability analysis and enhancement approach.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11231002,10971023,10901033,61104154)the Fundamental Research Funds for Central Universities of Chinathe Shanghai Shuguang Project(No.07SG38)
文摘The notions of metric sparsification property and finite decomposition complexity are recently introduced in metric geometry to study the coarse Novikov conjecture and the stable Borel conjecture. In this paper, it is proved that a metric space X has finite decomposition complexity with respect to metric sparsification property if and only if X itself has metric sparsification property. As a consequence, the authors obtain an alternative proof of a very recent result by Guentner, Tessera and Yu that all countable linear groups have the metric sparsification property and hence the operator norm localization property.
基金supported by the National Natural Science Foundation of China(Grant No.51321005)the State Scholarship Fund of China,the National 973 Project(Grant No.613294)State Key Laboratory of Electrical Insulation and Power Equipment(Grant No.EIPE17313)
文摘The integrated power system(IPS) is a foundation of all-electrical ships and vessels. The stability of IPS becomes a prerequisite of complicated cruise tasks. Thus, advanced stability analysis and regulation methods for IPS are of great importance. In this paper, a novel method is proposed for analyzing and enhancing transient stability of IPS, which is regarded as a cyber-physical system comprising of subsystems and connections. Criterions for determining input-output stability of such a system are firstly derived. Then, the stability analysis of IPS can be performed in the following two steps: 1) evaluating local input-output stability features of each subsystem independently through simulations. 2) Checking stability criterions with system topology and subsystem stability features. Moreover, synthetic approaches are proposed for stabilization and stability enhancement of IPS. To avoid system in-stability after major failures or topology changes, the optimal emergency control is performed to reconfigure subsystems. The other optimal regulation is used to strengthen system stability by adjusting subsystems' control parameters during normal operation conditions. Case studies on a typical IPS validate the proposed stability analysis and enhancement approach.
