Dear Editor,This letter proposes a deep synchronization control(DSC) method to synchronize grid-forming converters with power grids. The method involves constructing a novel controller for grid-forming converters base...Dear Editor,This letter proposes a deep synchronization control(DSC) method to synchronize grid-forming converters with power grids. The method involves constructing a novel controller for grid-forming converters based on the stable deep dynamics model. To enhance the performance of the controller, the dynamics model is optimized within the deep reinforcement learning(DRL) framework. Simulation results verify that the proposed method can reduce frequency deviation and improve active power responses.展开更多
Previously, the military establishment has been the primary developer and user of micro technologies associated with unmanned systems. As these technologies become available commercially, a need exists to integrate th...Previously, the military establishment has been the primary developer and user of micro technologies associated with unmanned systems. As these technologies become available commercially, a need exists to integrate the use of the technology into local or regional public safety and homeland security incidents. The purpose of this presentation is to explain several key factors to consider when using micro technologies and unmanned systems in support of public safety and homeland security officials. Real time information is critical to the decision making process for public safety and homeland security officials to make assessments and quickly resolve crisis situations. Unmanned micro-vehicles and micro technologies are well suited to remotely observe, gather essential information, and immediately relay it to incident responders. These technologies can provide extremely important support during responses to hostage situations, hazardous environments, search and rescue, natural disasters, border patrol and many others. The true benefit is having remote resources providing real time support to incident responders. This paper discusses the use of several different types of micro-vehicle platforms in public safety scenarios and their use of associated technologies such as GPS （Global Positioning System） autopilot, communication, and sensor devices.展开更多
The information of seismic response spectra is key to many problems concerned with aseismic structure and is also helpful for earthquake disaster relief if it is generated in time when earthquake happens. While curren...The information of seismic response spectra is key to many problems concerned with aseismic structure and is also helpful for earthquake disaster relief if it is generated in time when earthquake happens. While current numerical calculation methods suffer from poor precision, especially in frequency band near Nyquist frequency, we present a set of improved parameters for precision improvement. It is shown that precision of displacement and velocity response spectra are both further improved compared to current numerical algorithms. A uniform fitting formula is given for computing these parameters for damping ratio range of 0.01-0.9, quite convenient for practical application.展开更多
Ⅰ. EXECUTIVE SUMMARYAuthorities and emergency services used to be at the forefront of mobile communications–after all, respond-ing to emergencies has always required mobility. How-ever, the professionals’ technolog...Ⅰ. EXECUTIVE SUMMARYAuthorities and emergency services used to be at the forefront of mobile communications–after all, respond-ing to emergencies has always required mobility. How-ever, the professionals’ technologically leading position has diminished with the explosive growth of展开更多
The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual proble...The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual problem owing to the diversified geological engineering factors and complexity. The author made a detailed study based on surveys of large amount of geological engineering research on Donggang Power Plant slope project,discussed the comprehensive factors influencing the project,and gave analytical calculation and evaluation to the improved response surface of the slope project. The study result shows that the slope is stable,which can provide scientific basis for designing the slope.展开更多
This study adopts a reliability-based optimization approach for the failure mechanism analysis and design of the retaining wall considering nonlinear soil backfills.The assumed failure mechanism is represented by rigi...This study adopts a reliability-based optimization approach for the failure mechanism analysis and design of the retaining wall considering nonlinear soil backfills.The assumed failure mechanism is represented by rigid blocks within a kinematically admissible framework in a rotational coordinate system.Then the active and passive earth pressures are derived from the optimization procedure.A convenient way for incorporating seepage effects is proposed and implemented in the nonlinear upper bound analysis.Finally,a novel response surface method is employed to calculate the failure probability considering different probabilistic scenarios and distribution types with high calculation efficacy.The accuracy of the proposed method is evaluated using the Monte Carlo simulations with 1 million trials.Sensitivity analysis indicated that soil unit weight and initial cohesion are the critical factors dominating the failure probability of passive and active mechanism,respectively.The reliability-based design can be performed to obtain the safe range of the lateral force against nonlinear soil backfills with a target failure probability.展开更多
基金supported in part by the National Natural Science Foundation of China(62033005,62273270)the Natural Science Foundation of Shaanxi Province(2023JC-XJ17)
文摘Dear Editor,This letter proposes a deep synchronization control(DSC) method to synchronize grid-forming converters with power grids. The method involves constructing a novel controller for grid-forming converters based on the stable deep dynamics model. To enhance the performance of the controller, the dynamics model is optimized within the deep reinforcement learning(DRL) framework. Simulation results verify that the proposed method can reduce frequency deviation and improve active power responses.
文摘Previously, the military establishment has been the primary developer and user of micro technologies associated with unmanned systems. As these technologies become available commercially, a need exists to integrate the use of the technology into local or regional public safety and homeland security incidents. The purpose of this presentation is to explain several key factors to consider when using micro technologies and unmanned systems in support of public safety and homeland security officials. Real time information is critical to the decision making process for public safety and homeland security officials to make assessments and quickly resolve crisis situations. Unmanned micro-vehicles and micro technologies are well suited to remotely observe, gather essential information, and immediately relay it to incident responders. These technologies can provide extremely important support during responses to hostage situations, hazardous environments, search and rescue, natural disasters, border patrol and many others. The true benefit is having remote resources providing real time support to incident responders. This paper discusses the use of several different types of micro-vehicle platforms in public safety scenarios and their use of associated technologies such as GPS （Global Positioning System） autopilot, communication, and sensor devices.
基金supported by Science for Earthquake Resilience (XH12032)
文摘The information of seismic response spectra is key to many problems concerned with aseismic structure and is also helpful for earthquake disaster relief if it is generated in time when earthquake happens. While current numerical calculation methods suffer from poor precision, especially in frequency band near Nyquist frequency, we present a set of improved parameters for precision improvement. It is shown that precision of displacement and velocity response spectra are both further improved compared to current numerical algorithms. A uniform fitting formula is given for computing these parameters for damping ratio range of 0.01-0.9, quite convenient for practical application.
文摘Ⅰ. EXECUTIVE SUMMARYAuthorities and emergency services used to be at the forefront of mobile communications–after all, respond-ing to emergencies has always required mobility. How-ever, the professionals’ technologically leading position has diminished with the explosive growth of
文摘The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual problem owing to the diversified geological engineering factors and complexity. The author made a detailed study based on surveys of large amount of geological engineering research on Donggang Power Plant slope project,discussed the comprehensive factors influencing the project,and gave analytical calculation and evaluation to the improved response surface of the slope project. The study result shows that the slope is stable,which can provide scientific basis for designing the slope.
文摘This study adopts a reliability-based optimization approach for the failure mechanism analysis and design of the retaining wall considering nonlinear soil backfills.The assumed failure mechanism is represented by rigid blocks within a kinematically admissible framework in a rotational coordinate system.Then the active and passive earth pressures are derived from the optimization procedure.A convenient way for incorporating seepage effects is proposed and implemented in the nonlinear upper bound analysis.Finally,a novel response surface method is employed to calculate the failure probability considering different probabilistic scenarios and distribution types with high calculation efficacy.The accuracy of the proposed method is evaluated using the Monte Carlo simulations with 1 million trials.Sensitivity analysis indicated that soil unit weight and initial cohesion are the critical factors dominating the failure probability of passive and active mechanism,respectively.The reliability-based design can be performed to obtain the safe range of the lateral force against nonlinear soil backfills with a target failure probability.
