A two dimensional transient numerical analysis and computational module for simulation of electrical and thermal characteristics during electrode melting and metal transfer involved in Gas-Metal-Arc-Welding （GMAW） p...A two dimensional transient numerical analysis and computational module for simulation of electrical and thermal characteristics during electrode melting and metal transfer involved in Gas-Metal-Arc-Welding （GMAW） processes is presented. Solution of non.linear transient heat transfer equation is carried out using a control volume finite difference technique. The computational module also includes controlling and regulation algorithms of industrial welding power sources. The simulation results are the current and voltage waveforms, mean voltage drops at different parts of circuit, total electric power, cathode, anode and arc powers and arc length. We describe application of the model for normal process （constant voltage） and for pulsed processes with U/I and Ill- modulation modes. The comparisons with experimental waveforms of current and voltage show that the model predicts current, voltage and electric power with a high accuracy. The model is used in simulation package SimWeld for calculation of heat flux into the work-piece and the weld seam formation. From the calculated heat flux and weld pool sizes, an equivalent volumetric heat source according to Goldak model, can be generated. The method was implemented and investigated with the simulation software SimWeld developed by the ISF at RWTH Aachen University.展开更多
The dynamics of complex gene regulation systems can be simulated by the Gillespie algorithm. The classic Gillespie algorithm is appropriate to simulate a stochastic
cyber-space has become increasingly important for human activities,and intelligent algorithms are widely used in cyber-space,we are rapidly entering an intelligent society.Now,algorithmic enforcement and regulations o...cyber-space has become increasingly important for human activities,and intelligent algorithms are widely used in cyber-space,we are rapidly entering an intelligent society.Now,algorithmic enforcement and regulations of law have posed non-negligible issues.As algorithmic enforcement of copyright law was introduced earlier than that of other laws,it provides a helpful observation perspective.The worldwide practice of copyright enforcement has gradually departed from traditional"safe harbor provisions,"and has emphasized prior examination of shared contents uploaded by Internet service providers'(ISPs)users through the following three dimensions:automated infringement detection algorithms voluntarily used by the ISPs,heavier judicial liability of ISPs,and updated legislation principles.Thus,innovations and development have stimulated new mechanisms and regulations for enforcing copyright in cyberspace.Algorithmic enforcement of copyright law in an intelligent society is essential and meaningful.The copyright regulation mechanisms should be guided by jurisprudential principles and concepts featuring the principles of(a)legitimate and efficient flow of information,(b)balance between and among algorithmic power,public power and private rights,(c)boosting the sharing economy and the new gig economy,and(d)promoting social governance philosophy of"coconstruction,co-governance and sharing."These principles are meaningful for creation of a new mechanism for balancing interests between ISPs and their users,and for introducing the pluralistic co-governance mechanism beyond simply practicing"filtering obligations."In addition,these principles are significant for improving a certification with credibility of copyright status and ownership,and for advancing a mechanism for onlinecollegiate-panel dispute resolution.展开更多
文摘A two dimensional transient numerical analysis and computational module for simulation of electrical and thermal characteristics during electrode melting and metal transfer involved in Gas-Metal-Arc-Welding （GMAW） processes is presented. Solution of non.linear transient heat transfer equation is carried out using a control volume finite difference technique. The computational module also includes controlling and regulation algorithms of industrial welding power sources. The simulation results are the current and voltage waveforms, mean voltage drops at different parts of circuit, total electric power, cathode, anode and arc powers and arc length. We describe application of the model for normal process （constant voltage） and for pulsed processes with U/I and Ill- modulation modes. The comparisons with experimental waveforms of current and voltage show that the model predicts current, voltage and electric power with a high accuracy. The model is used in simulation package SimWeld for calculation of heat flux into the work-piece and the weld seam formation. From the calculated heat flux and weld pool sizes, an equivalent volumetric heat source according to Goldak model, can be generated. The method was implemented and investigated with the simulation software SimWeld developed by the ISF at RWTH Aachen University.
文摘The dynamics of complex gene regulation systems can be simulated by the Gillespie algorithm. The classic Gillespie algorithm is appropriate to simulate a stochastic
基金Project of Scientific Research Fund of Renmin University of China(2015030030)supported by the Fundamental Research Funds for the Central Universities.
文摘cyber-space has become increasingly important for human activities,and intelligent algorithms are widely used in cyber-space,we are rapidly entering an intelligent society.Now,algorithmic enforcement and regulations of law have posed non-negligible issues.As algorithmic enforcement of copyright law was introduced earlier than that of other laws,it provides a helpful observation perspective.The worldwide practice of copyright enforcement has gradually departed from traditional"safe harbor provisions,"and has emphasized prior examination of shared contents uploaded by Internet service providers'(ISPs)users through the following three dimensions:automated infringement detection algorithms voluntarily used by the ISPs,heavier judicial liability of ISPs,and updated legislation principles.Thus,innovations and development have stimulated new mechanisms and regulations for enforcing copyright in cyberspace.Algorithmic enforcement of copyright law in an intelligent society is essential and meaningful.The copyright regulation mechanisms should be guided by jurisprudential principles and concepts featuring the principles of(a)legitimate and efficient flow of information,(b)balance between and among algorithmic power,public power and private rights,(c)boosting the sharing economy and the new gig economy,and(d)promoting social governance philosophy of"coconstruction,co-governance and sharing."These principles are meaningful for creation of a new mechanism for balancing interests between ISPs and their users,and for introducing the pluralistic co-governance mechanism beyond simply practicing"filtering obligations."In addition,these principles are significant for improving a certification with credibility of copyright status and ownership,and for advancing a mechanism for onlinecollegiate-panel dispute resolution.
