Subgrid nonlinear interaction and energy transfer are analyzed using direct numerical simulations of isotropic turbulence. Influences of cutoff wave number at different ranges of scale on the energetics and dynamics h...Subgrid nonlinear interaction and energy transfer are analyzed using direct numerical simulations of isotropic turbulence. Influences of cutoff wave number at different ranges of scale on the energetics and dynamics have been investigated. It is observed that subgrid-subgrid interaction dominates the turbulent dynamics when cut-off wave number locates in the energy-containing range while resolved-subgrid interaction dominates if it is in the dissipation range. By decomposing the subgrid energy transfer and nonlinear interaction into ‘forward’ and ‘backward’ groups according to the sign of triadic interaction, we find that individually each group has very large contribution, but the net of them is much smaller, implying that tremendous cancellation happens between these two groups.展开更多
Advanced Metering Infrastructure （AMI） enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers cha...Advanced Metering Infrastructure （AMI） enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers challenges the current power systems with system integration and cooperation and security issues. In this paper, the authors introduce a service-oriented approach to AMI aiming at solving the intercommunication problem and meanwhile providing a trust and secure environment for smart grids. In this approach heterogeneous systems expose services to the network. System integration and cooperation are done through service composition. A generic service interfacing method is designed to develop standardized services for heterogeneous power systems. Moreover, role-based access control mechanism is used to guarantee the secure access to smart grids. With the seamless communication between consumers and power systems and among power systems themselves, this service-oriented AMI can associate consumers with actual system workload and furthermore support the intelligent running of power systems.展开更多
We fabricate titanium disulfide(TiS2) using a liquid exfoliation method and subsequently a TiS2-based device by optically depositing the TiS2 material onto the microfiber. This device exhibits a strong nonlinear satur...We fabricate titanium disulfide(TiS2) using a liquid exfoliation method and subsequently a TiS2-based device by optically depositing the TiS2 material onto the microfiber. This device exhibits a strong nonlinear saturable absorption property with an optical modulation depth of 8.3% at 1560 nm. With the implementation of this all-fiber TiS2-based saturable absorber, we demonstrate that both mode-locking and Q-switching operation can be obtained in a turn-key all-fiber erbium-doped laser cavity. Our findings constitute the first example, to the best of our knowledge, of a TiS2-based saturable absorber for ultrashort pulse generation and highlight the great potential of such devices in two-dimensional nanomaterials-related photonics.展开更多
文摘Subgrid nonlinear interaction and energy transfer are analyzed using direct numerical simulations of isotropic turbulence. Influences of cutoff wave number at different ranges of scale on the energetics and dynamics have been investigated. It is observed that subgrid-subgrid interaction dominates the turbulent dynamics when cut-off wave number locates in the energy-containing range while resolved-subgrid interaction dominates if it is in the dissipation range. By decomposing the subgrid energy transfer and nonlinear interaction into ‘forward’ and ‘backward’ groups according to the sign of triadic interaction, we find that individually each group has very large contribution, but the net of them is much smaller, implying that tremendous cancellation happens between these two groups.
文摘Advanced Metering Infrastructure （AMI） enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers challenges the current power systems with system integration and cooperation and security issues. In this paper, the authors introduce a service-oriented approach to AMI aiming at solving the intercommunication problem and meanwhile providing a trust and secure environment for smart grids. In this approach heterogeneous systems expose services to the network. System integration and cooperation are done through service composition. A generic service interfacing method is designed to develop standardized services for heterogeneous power systems. Moreover, role-based access control mechanism is used to guarantee the secure access to smart grids. With the seamless communication between consumers and power systems and among power systems themselves, this service-oriented AMI can associate consumers with actual system workload and furthermore support the intelligent running of power systems.
基金Fundamental Research Funds for the Central UniversitiesNational Natural Science Foundation of China(NSFC)(51778030,61505005,61505112)
文摘We fabricate titanium disulfide(TiS2) using a liquid exfoliation method and subsequently a TiS2-based device by optically depositing the TiS2 material onto the microfiber. This device exhibits a strong nonlinear saturable absorption property with an optical modulation depth of 8.3% at 1560 nm. With the implementation of this all-fiber TiS2-based saturable absorber, we demonstrate that both mode-locking and Q-switching operation can be obtained in a turn-key all-fiber erbium-doped laser cavity. Our findings constitute the first example, to the best of our knowledge, of a TiS2-based saturable absorber for ultrashort pulse generation and highlight the great potential of such devices in two-dimensional nanomaterials-related photonics.
