近年来,数字孪生(Digital Twin)一词迅速蹿红,成为一个炙手可热的概念。但随着工业界和学术界对数字孪生的不断解读,其含义却越发扑朔迷离,和其他一些相关概念的界限也越来越模糊。数字孪生到底是什么,能做什么,边界在哪里,它和建模仿...近年来,数字孪生(Digital Twin)一词迅速蹿红,成为一个炙手可热的概念。但随着工业界和学术界对数字孪生的不断解读,其含义却越发扑朔迷离,和其他一些相关概念的界限也越来越模糊。数字孪生到底是什么,能做什么,边界在哪里,它和建模仿真是什么关系等等问题令很多人困惑。本文尝试对其中的一些疑惑进行粗浅的分析。1 Digital Twin到底指什么?展开更多
Digital twin(DT)framework is introduced in the context of application for power grid online analysis.In the development process of a new power grid real-time online analysis system,an online analysis digital twin(OADT...Digital twin(DT)framework is introduced in the context of application for power grid online analysis.In the development process of a new power grid real-time online analysis system,an online analysis digital twin(OADT)has been implemented to realize the new online analysis architecture.The OADT approach is presented and its prominent features are discussed.The presentation,discussion,and performance testing are based on a large-scale grid network model(40K+buses),exported directly from the EMS system of an actual power grid.A plan to apply the OADT approach to digitize power grid dispatching rules is also outlined.展开更多
As the next-generation manufacturing system,intelligent manufacturing enables better quality,higher productivity,lower cost,and increased manufacturing flexibility.The concept of sustainability is receiving increasing...As the next-generation manufacturing system,intelligent manufacturing enables better quality,higher productivity,lower cost,and increased manufacturing flexibility.The concept of sustainability is receiving increasing attention,and sustainable manufacturing is evolving.The digital twin is an emerging technology used in intelligent manufacturing that can grasp the state of intelligent manufacturing systems in real-time and predict system failures.Sustainable intelligent manufacturing based on a digital twin has advantages in practical applications.To fully understand the intelligent manufacturing that provides the digital twin,this study reviews both technologies and discusses the sustainability of intelligent manufacturing.Firstly,the relevant content of intelligent manufacturing,including intelligent manufacturing equipment,systems,and services,is analyzed.In addition,thesustainability of intelligent manufacturing is discussed.Subsequently,a digital twin and its application are introduced along with the development of intelligent manufacturing based on the digital twin technology.Finally,combined with the current status,the future development direction of intelligent manufacturing is presented.展开更多
Compared with using semi-automatic gas shielded arc welding, using automatic TANDEM twin wire welding and twin wire gas metal arc welding （GMAW） to weld Q690 steel, a low-alloy high-strength structural steel used in...Compared with using semi-automatic gas shielded arc welding, using automatic TANDEM twin wire welding and twin wire gas metal arc welding （GMAW） to weld Q690 steel, a low-alloy high-strength structural steel used in the hydraulic support in the fully-mechanized mining face, the welding speed, deposition rate, production environment and welding quality can be obviously improved. Compared with GMAW twin wire welding, a refined micro- structure in the weld and heat-affected zone （HAZ）, narrow HAZ and improved joint strength were achieved with TANDEM on Q690. Also, due to the push-pull pulsed way in TANDEM welding, the droplet transfer, distribution on heat flow and interaction between two arcs were completely different from those in GMAW twin wire system. The heat input of TANDEM is only about 76.6% of GMAW, and correspondingly, the welding speed and welding seam can be obviously improved. The complete oscillation caused by TANDEM pulsed current occurred in the welding pool, which refined the grains in the microstructure. The results show that TANDEM twin wire welding is very suitable in the welding of Q690 used in the hydraulic support.展开更多
Many countries and governments consider smart cities a solution to global warming,population growth,and resource depletion.Numerous challenges arise while creating a smart city.Digital twins,along with the Internet of...Many countries and governments consider smart cities a solution to global warming,population growth,and resource depletion.Numerous challenges arise while creating a smart city.Digital twins,along with the Internet of Things,fifth-generation wireless systems,blockchain,collaborative computing,simulation,and artificial intelligence technologies,offer great potential in the transformation of the current urban governance paradigm toward smart cities.In this paper,the concept of a digital twin city(DTC)is proposed.The characteristics,key technologies,and application scenarios of a DTC are elaborated upon.Further,we discuss the theories,research directions,and framework regarding DTCs.展开更多
In this paper,a new parallel controller is developed for continuous-time linear systems.The main contribution of the method is to establish a new parallel control law,where both state and control are considered as the...In this paper,a new parallel controller is developed for continuous-time linear systems.The main contribution of the method is to establish a new parallel control law,where both state and control are considered as the input.The structure of the parallel control is provided,and the relationship between the parallel control and traditional feedback controls is presented.Considering the situations that the systems are controllable and incompletely controllable,the properties of the parallel control law are analyzed.The parallel controller design algorithms are given under the conditions that the systems are controllable and incompletely controllable.Finally,numerical simulations are carried out to demonstrate the effectiveness and applicability of the present method.Index Terms-Continuous-time linear systems,digital twin,parallel controller,parallel intelligence,parallel systems.展开更多
文摘近年来,数字孪生(Digital Twin)一词迅速蹿红,成为一个炙手可热的概念。但随着工业界和学术界对数字孪生的不断解读,其含义却越发扑朔迷离,和其他一些相关概念的界限也越来越模糊。数字孪生到底是什么,能做什么,边界在哪里,它和建模仿真是什么关系等等问题令很多人困惑。本文尝试对其中的一些疑惑进行粗浅的分析。1 Digital Twin到底指什么?
基金This work was supported by National Natural Science Foundation of China under the Grant U1766214.
文摘Digital twin(DT)framework is introduced in the context of application for power grid online analysis.In the development process of a new power grid real-time online analysis system,an online analysis digital twin(OADT)has been implemented to realize the new online analysis architecture.The OADT approach is presented and its prominent features are discussed.The presentation,discussion,and performance testing are based on a large-scale grid network model(40K+buses),exported directly from the EMS system of an actual power grid.A plan to apply the OADT approach to digitize power grid dispatching rules is also outlined.
基金supported by the National Natural Science Foundation of China(Grant No.51675319)Shanghai Science and Technology Committee Project(Grant No.19511104702).
文摘As the next-generation manufacturing system,intelligent manufacturing enables better quality,higher productivity,lower cost,and increased manufacturing flexibility.The concept of sustainability is receiving increasing attention,and sustainable manufacturing is evolving.The digital twin is an emerging technology used in intelligent manufacturing that can grasp the state of intelligent manufacturing systems in real-time and predict system failures.Sustainable intelligent manufacturing based on a digital twin has advantages in practical applications.To fully understand the intelligent manufacturing that provides the digital twin,this study reviews both technologies and discusses the sustainability of intelligent manufacturing.Firstly,the relevant content of intelligent manufacturing,including intelligent manufacturing equipment,systems,and services,is analyzed.In addition,thesustainability of intelligent manufacturing is discussed.Subsequently,a digital twin and its application are introduced along with the development of intelligent manufacturing based on the digital twin technology.Finally,combined with the current status,the future development direction of intelligent manufacturing is presented.
基金Item Sponsored by National Natural Science Foundation of China(51005106)A Project Funded by Priority Academic Program Development of Jiangsu Higher Education Institutions of ChinaAdvanced Welding Technology Key Laboratory Open Foundation Funded Projects in Jiangsu Province of China
文摘Compared with using semi-automatic gas shielded arc welding, using automatic TANDEM twin wire welding and twin wire gas metal arc welding （GMAW） to weld Q690 steel, a low-alloy high-strength structural steel used in the hydraulic support in the fully-mechanized mining face, the welding speed, deposition rate, production environment and welding quality can be obviously improved. Compared with GMAW twin wire welding, a refined micro- structure in the weld and heat-affected zone （HAZ）, narrow HAZ and improved joint strength were achieved with TANDEM on Q690. Also, due to the push-pull pulsed way in TANDEM welding, the droplet transfer, distribution on heat flow and interaction between two arcs were completely different from those in GMAW twin wire system. The heat input of TANDEM is only about 76.6% of GMAW, and correspondingly, the welding speed and welding seam can be obviously improved. The complete oscillation caused by TANDEM pulsed current occurred in the welding pool, which refined the grains in the microstructure. The results show that TANDEM twin wire welding is very suitable in the welding of Q690 used in the hydraulic support.
文摘Many countries and governments consider smart cities a solution to global warming,population growth,and resource depletion.Numerous challenges arise while creating a smart city.Digital twins,along with the Internet of Things,fifth-generation wireless systems,blockchain,collaborative computing,simulation,and artificial intelligence technologies,offer great potential in the transformation of the current urban governance paradigm toward smart cities.In this paper,the concept of a digital twin city(DTC)is proposed.The characteristics,key technologies,and application scenarios of a DTC are elaborated upon.Further,we discuss the theories,research directions,and framework regarding DTCs.
基金supported in part by the National Key Research and Development Program of China(2018AAA0101502,2018YFB1702300)the National Natural Science Foundation of China(61722312,61533019,U1811463,61533017)。
文摘In this paper,a new parallel controller is developed for continuous-time linear systems.The main contribution of the method is to establish a new parallel control law,where both state and control are considered as the input.The structure of the parallel control is provided,and the relationship between the parallel control and traditional feedback controls is presented.Considering the situations that the systems are controllable and incompletely controllable,the properties of the parallel control law are analyzed.The parallel controller design algorithms are given under the conditions that the systems are controllable and incompletely controllable.Finally,numerical simulations are carried out to demonstrate the effectiveness and applicability of the present method.Index Terms-Continuous-time linear systems,digital twin,parallel controller,parallel intelligence,parallel systems.
