In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries...In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries. The proposed model is composed of several connected coil springs in series. The sum of torsion deformation on every coil is equivalent to the soft tissue surface deformation. The calculation of the model is simple because the method for calculating the torsion deformation for each coil spring is the same. The virtual surgery simulation system is established on PHANTOM OMNI haptic device based on the Open GL 3 D graphic interface and VC + + software,and it is used to simulate the torsion deformation of virtual legs and arms. Experimental results show that the proposed model can effectively simulate the torsion deformation of soft tissue while being of real-time performance and simplicity,which can well meet requirements of virtual operation simulations.展开更多
A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting c...A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting coils,the quench protection(QP)system,which employs fuse-based commutation technology,is designed.This paper presents an analytical model to investigate the commutation process in the QP circuit.The model consists of the QP circuit equations,the breaker arc model,the fuse pre-arc model,and the fuse arc model.The model is employed in the whole commutation process including current transfer from breaker branch to the fuse branch model,then from fuse branch to the discharge resistor branch,and current decrease to zero in the discharge resistor.The experiment result verified the effectiveness of the presented model.The model might be helpful for design of the fuse and optimization of the commutation circuit.展开更多
No-insulation(NI)coils emerged as a viable alternative to traditional insulated(INS)high temperature super-conducting(HTS)coils primarily due to their inherent ability to self-protect during quench and enhanced me-cha...No-insulation(NI)coils emerged as a viable alternative to traditional insulated(INS)high temperature super-conducting(HTS)coils primarily due to their inherent ability to self-protect during quench and enhanced me-chanical stability.When coils carrying direct current(DC)are exposed to an external alternating current(AC)magnetic field,total loss in the coil is the sum of magnetisation loss due to the AC field and dynamic loss arising from the interaction between the DC current and the AC field.In this work,we numerically study the total loss and its components in NI and INS double-pancake coils(DPCs)of identical dimensions,wound with 4 mm wide SuperPower Rare-earth barium copper oxide(ReBCO)coated conductor(CC)tapes at 77 K.The analysis is carried out for external AC magnetic fields up to 200 mT at 72.73 Hz,with the coil carrying DC current up to 90%of the coil self-field critical current.The results show that under a perpendicular magnetic field,the total loss and its components in the INS-DPC are higher than in the NI-DPC,which is attributed to the presence of insu-lation which hinders the current bypass.The NI-DPC and INS-DPC coils show similar electromagnetic behaviour under the perpendicular field,and the evolution of dynamic resistance,which gives rise to dynamic loss,is also similar.Under parallel field the loss in the NI-DPC is higher than that for the perpendicular field,and the coil level shielding similar to bulk superconductor is also observed.Surprisingly,under parallel fields,a dynamic resistance higher than that under perpendicular fields is evident in the NI-DPC,arising from a finite average electric field over a cycle.展开更多
基金Supported by the National Natural Science Foundation of China(No.61502240,61502096,61304205,61773219)the Natural Science Foundation of Jiangsu Province(No.BK20141002,BK20150634)
文摘In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries. The proposed model is composed of several connected coil springs in series. The sum of torsion deformation on every coil is equivalent to the soft tissue surface deformation. The calculation of the model is simple because the method for calculating the torsion deformation for each coil spring is the same. The virtual surgery simulation system is established on PHANTOM OMNI haptic device based on the Open GL 3 D graphic interface and VC + + software,and it is used to simulate the torsion deformation of virtual legs and arms. Experimental results show that the proposed model can effectively simulate the torsion deformation of soft tissue while being of real-time performance and simplicity,which can well meet requirements of virtual operation simulations.
文摘A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting coils,the quench protection(QP)system,which employs fuse-based commutation technology,is designed.This paper presents an analytical model to investigate the commutation process in the QP circuit.The model consists of the QP circuit equations,the breaker arc model,the fuse pre-arc model,and the fuse arc model.The model is employed in the whole commutation process including current transfer from breaker branch to the fuse branch model,then from fuse branch to the discharge resistor branch,and current decrease to zero in the discharge resistor.The experiment result verified the effectiveness of the presented model.The model might be helpful for design of the fuse and optimization of the commutation circuit.
基金supported in part by MBIE New Zealand through the Advanced Energy Technology Platform program‘High Power Electric Motors for Large-Scale Transport’(contract RTVU2004)by the Air Force Office of Scientific Research(award FA2386-22-1-4054)+1 种基金by the Royal Society Marsden Fund of New Zealand Vice-Chancellors’Committee(grant MFP-VUW2205)‘Underpinning High-Temperature Superconducting Nuclear Fusion Reactor Technology’.
文摘No-insulation(NI)coils emerged as a viable alternative to traditional insulated(INS)high temperature super-conducting(HTS)coils primarily due to their inherent ability to self-protect during quench and enhanced me-chanical stability.When coils carrying direct current(DC)are exposed to an external alternating current(AC)magnetic field,total loss in the coil is the sum of magnetisation loss due to the AC field and dynamic loss arising from the interaction between the DC current and the AC field.In this work,we numerically study the total loss and its components in NI and INS double-pancake coils(DPCs)of identical dimensions,wound with 4 mm wide SuperPower Rare-earth barium copper oxide(ReBCO)coated conductor(CC)tapes at 77 K.The analysis is carried out for external AC magnetic fields up to 200 mT at 72.73 Hz,with the coil carrying DC current up to 90%of the coil self-field critical current.The results show that under a perpendicular magnetic field,the total loss and its components in the INS-DPC are higher than in the NI-DPC,which is attributed to the presence of insu-lation which hinders the current bypass.The NI-DPC and INS-DPC coils show similar electromagnetic behaviour under the perpendicular field,and the evolution of dynamic resistance,which gives rise to dynamic loss,is also similar.Under parallel field the loss in the NI-DPC is higher than that for the perpendicular field,and the coil level shielding similar to bulk superconductor is also observed.Surprisingly,under parallel fields,a dynamic resistance higher than that under perpendicular fields is evident in the NI-DPC,arising from a finite average electric field over a cycle.
