To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability constraints.However,comp...To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability constraints.However,computational complexities lead to over-conservative pre-settings of transfer limit,which further induce undesirable and non-technical congestion of power transfer.To conquer this barrier,a scenario-classification hybrid-based banding method is proposed.A cluster technique is adopted to separate similarities from historical and generated operating condition dataset.With a practical rule,transfer limits are approximated for each operating cluster.Then,toward an interpretable online transfer limit decision,costsensitive learning is applied to identify cluster affiliation to assign a transfer limit for a given operation.In this stage,critical variables that affect the transfer limit are also picked out via mean impact value.This enables us to construct low-complexity and dispatcher-friendly rules for fast determination of transfer limit.The numerical case studies on the IEEE 39-bus system and a real-world regional power system in China illustrate the effectiveness and conservativeness of the proposed method.展开更多
Anuran skin is a typical natural biomaterial with multifunctional features.A specific comparison of mechanical performance and morphology related to them was performed in the skin of Rana dybowskii and Bufo gargarizan...Anuran skin is a typical natural biomaterial with multifunctional features.A specific comparison of mechanical performance and morphology related to them was performed in the skin of Rana dybowskii and Bufo gargarizans using the tensile testing technique and morphological equipment.Rana dybowskii's skin has soft smooth surface covered by polygonal epidermal cells,while the Bufo gargarizans species has tough and uneven skin surface due to numerous verrucae structures.The collagen fibre bundles in lower dermis of Bufo gargarizans have wavelike organisation while the bundles of Rana dybowskii show a parallel arrangement.The mean elastic modulus of Rana dybowskii was nine times higher than that of Bufo gargarizans.This study clarified that the arrangement of collagen fibres play an important role in the strength and elasticity of skin material.展开更多
In this paper, the stability in Lagrange sense of a class of stochastic static neural networks with mixed time delays is studied. Based on the Lyapunov stability theory and with the help of stochastic analysis techniq...In this paper, the stability in Lagrange sense of a class of stochastic static neural networks with mixed time delays is studied. Based on the Lyapunov stability theory and with the help of stochastic analysis technique, the criteria for the stability in Lagrange sense of stochastic static neural networks with mixed time delays is obtained. One example is given to verify the advantage and applicability of the proposed results.展开更多
基金supported in part by State Grid Corporation of China Project“Research on high penetrated renewable energy oriented intelligent identification for curtailment impacts and aid decision-making for promoting consumption in regional power grids”(No.5108-202135035A-0-0-00).
文摘To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability constraints.However,computational complexities lead to over-conservative pre-settings of transfer limit,which further induce undesirable and non-technical congestion of power transfer.To conquer this barrier,a scenario-classification hybrid-based banding method is proposed.A cluster technique is adopted to separate similarities from historical and generated operating condition dataset.With a practical rule,transfer limits are approximated for each operating cluster.Then,toward an interpretable online transfer limit decision,costsensitive learning is applied to identify cluster affiliation to assign a transfer limit for a given operation.In this stage,critical variables that affect the transfer limit are also picked out via mean impact value.This enables us to construct low-complexity and dispatcher-friendly rules for fast determination of transfer limit.The numerical case studies on the IEEE 39-bus system and a real-world regional power system in China illustrate the effectiveness and conservativeness of the proposed method.
文摘Anuran skin is a typical natural biomaterial with multifunctional features.A specific comparison of mechanical performance and morphology related to them was performed in the skin of Rana dybowskii and Bufo gargarizans using the tensile testing technique and morphological equipment.Rana dybowskii's skin has soft smooth surface covered by polygonal epidermal cells,while the Bufo gargarizans species has tough and uneven skin surface due to numerous verrucae structures.The collagen fibre bundles in lower dermis of Bufo gargarizans have wavelike organisation while the bundles of Rana dybowskii show a parallel arrangement.The mean elastic modulus of Rana dybowskii was nine times higher than that of Bufo gargarizans.This study clarified that the arrangement of collagen fibres play an important role in the strength and elasticity of skin material.
基金supported by the National Natural Science Foundation of China(11171374)Natural Science Foundation of Shandong Province(ZR2011AZ001)
文摘In this paper, the stability in Lagrange sense of a class of stochastic static neural networks with mixed time delays is studied. Based on the Lyapunov stability theory and with the help of stochastic analysis technique, the criteria for the stability in Lagrange sense of stochastic static neural networks with mixed time delays is obtained. One example is given to verify the advantage and applicability of the proposed results.
