In this paper, the thermal field of double wire welding is simulated by using ANSYS software. Simulation results were shown that the total heat input (E) is the most significant parameters to change the value of t8/5;...In this paper, the thermal field of double wire welding is simulated by using ANSYS software. Simulation results were shown that the total heat input (E) is the most significant parameters to change the value of t8/5;By the mean of rationally controlling the proportion of the front arc heat input (E1) in the total heat input (E) and appropriately selecting double wire spacing (L), It is effective means to get the double wire welding thermal cycle. By the way of simulation, it is possible to manage the thermal input in the double welding wires and to control the temperature field and cooling rate that are fundamental for the final joint quality, it is great importance guidance to optimize the double wire welding process parameters.展开更多
We theoretically investigate the spin filtering transport of double parallel quantum wires(QWs) side-coupled to a grapheme sheet and sandwiched between two ferromagnetic(FM) leads.The dependences of the wire-graphene ...We theoretically investigate the spin filtering transport of double parallel quantum wires(QWs) side-coupled to a grapheme sheet and sandwiched between two ferromagnetic(FM) leads.The dependences of the wire-graphene coupling strength,wire-wire coupling strength,as well as the spin polarization of the ferromagnetic leads are studied.It is found that the wire-graphene coupling strength tends to reduce the current and the wire-wire coupling strength can first reinforce and then decrease the current.The spin polarization strength has an enhanced(identical) effect on the current under the parallel(anti-parallel) alignment of the FM leads,which gives rise to an obvious spin-filter and tunnel magnetoresistance(TMR) effect.Our results suggest that such a theoretical model can stimulate some experimental investigations about the spin-filter devices.展开更多
At present, 220kV transmission line usually adopts double split wire in order to meet the electrical characteristics, reduce the surface potential gradient, avoid the electromagnetic force between the wires, make the ...At present, 220kV transmission line usually adopts double split wire in order to meet the electrical characteristics, reduce the surface potential gradient, avoid the electromagnetic force between the wires, make the current between the two wires, will not produce a big pull, or even if the moment of pull, it can also be restored to the original position after the accident. The spacer rod on the double split wire is not correct or disturbed by the vibration during the wire, which will cause loosening and damage to threaten the normal operation of the power system. This paper describes a special tool to replace or add the isolation rod to replace and install the double-wire isolation rod. The results of this study can provide a reference for replacing 220kV double split wire spacers.展开更多
Amongst the many known techniques used for the management of fractures of the patella, the tension band wire fixation is a reliable treatment modality and has given consistently good results. In transverse patellar fr...Amongst the many known techniques used for the management of fractures of the patella, the tension band wire fixation is a reliable treatment modality and has given consistently good results. In transverse patellar fractures, a combination of cerclage wiring and tension band fixation gives a good mechanical stability and an environment conducive to healing. The fracture described herein is classified as 45-C1 (based on Orthopaedic Trauma Association classification) of the right knee of a forty three years old male patient. It was fixed with three vertical 1.5 mm K wires and double cerclage wire looped proximally through the quadriceps tendon and distally through the patellar ligament in a double figure-of-eight configuration. The average follow-up period was 7 months. The Activity of Daily Living Scale (ADLS) of the Knee Outcome Survey was used to assess symptoms and functional capability of the knee. The fracture union was achieved at an average of 10 weeks. Full range of knee motion was achieved by end of the third postoperative month. No complications, such as infection and implant failure were noted. The technique aims to stress the advantage of giving a balanced fixation addressing the bony elements (the fractured ends) as well as the soft tissue (the extensor apparatus).展开更多
Introduction Endoscopic ultrasound-guided hepaticogastrostomy(EUS-HGS)is widely used;however,it may be associated with adverse events(AEs),such as stent migration,bleeding,bile leakage,and bile peritonitis[1].Safer te...Introduction Endoscopic ultrasound-guided hepaticogastrostomy(EUS-HGS)is widely used;however,it may be associated with adverse events(AEs),such as stent migration,bleeding,bile leakage,and bile peritonitis[1].Safer techniques are needed to improve patient outcomes and facilitate effective trainee education.展开更多
As an improvement of the combinatorial realization of totally positive matrices via the essential positive weightings of certain planar network by S.Fomin and A.Zelevinsky[7],in this paper,we give a test method of pos...As an improvement of the combinatorial realization of totally positive matrices via the essential positive weightings of certain planar network by S.Fomin and A.Zelevinsky[7],in this paper,we give a test method of positive definite matrices via the planar networks and the so-called mixing-type sub-cluster algebras respectively,introduced here originally.This work firstly gives a combinatorial realization of all matrices through planar network,and then sets up a test method for positive definite matrices by LDU-decompositions and the horizontal weightings of all lines in their planar networks.On the other hand,mainly the relationship is built between positive definite matrices and mixing-type sub-cluster algebras.展开更多
The common vibration of cable caused by rain-wind combination has been known as most typical type and a lot kind of its countermeasures has been proposed for suppressing this phenomenon. Recently, stayed-cables were a...The common vibration of cable caused by rain-wind combination has been known as most typical type and a lot kind of its countermeasures has been proposed for suppressing this phenomenon. Recently, stayed-cables were also proved that they could be excited in dry state （without rain）, which is called dry-galloping. Recently, its mechanisms have been explained by axial flow, Reynolds number and so on. To clarify the characteristics of this galloping, wind tunnel test of a cable model with various kinds of wind angle was conducted. Then, three types of countermeasure were examined to suppress dry- galloping of bridge cable. The tests confirmed that the occurrence of dry-galloping depends on relative wind attacked angles and onset reduced wind speed. Furthermore, single spiral wire, double spiral wire and circular ring were found to have high effectiveness in mitigating this galloping when those are installed properly.展开更多
文摘In this paper, the thermal field of double wire welding is simulated by using ANSYS software. Simulation results were shown that the total heat input (E) is the most significant parameters to change the value of t8/5;By the mean of rationally controlling the proportion of the front arc heat input (E1) in the total heat input (E) and appropriately selecting double wire spacing (L), It is effective means to get the double wire welding thermal cycle. By the way of simulation, it is possible to manage the thermal input in the double welding wires and to control the temperature field and cooling rate that are fundamental for the final joint quality, it is great importance guidance to optimize the double wire welding process parameters.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11174214,11204192the NSAF Joint Fund Jointly set up by the National Natural Science Foundation of Chinathe Chinese Academy of Engineering Physics under Grant Nos.U1230201and U1430117
文摘We theoretically investigate the spin filtering transport of double parallel quantum wires(QWs) side-coupled to a grapheme sheet and sandwiched between two ferromagnetic(FM) leads.The dependences of the wire-graphene coupling strength,wire-wire coupling strength,as well as the spin polarization of the ferromagnetic leads are studied.It is found that the wire-graphene coupling strength tends to reduce the current and the wire-wire coupling strength can first reinforce and then decrease the current.The spin polarization strength has an enhanced(identical) effect on the current under the parallel(anti-parallel) alignment of the FM leads,which gives rise to an obvious spin-filter and tunnel magnetoresistance(TMR) effect.Our results suggest that such a theoretical model can stimulate some experimental investigations about the spin-filter devices.
文摘At present, 220kV transmission line usually adopts double split wire in order to meet the electrical characteristics, reduce the surface potential gradient, avoid the electromagnetic force between the wires, make the current between the two wires, will not produce a big pull, or even if the moment of pull, it can also be restored to the original position after the accident. The spacer rod on the double split wire is not correct or disturbed by the vibration during the wire, which will cause loosening and damage to threaten the normal operation of the power system. This paper describes a special tool to replace or add the isolation rod to replace and install the double-wire isolation rod. The results of this study can provide a reference for replacing 220kV double split wire spacers.
文摘Amongst the many known techniques used for the management of fractures of the patella, the tension band wire fixation is a reliable treatment modality and has given consistently good results. In transverse patellar fractures, a combination of cerclage wiring and tension band fixation gives a good mechanical stability and an environment conducive to healing. The fracture described herein is classified as 45-C1 (based on Orthopaedic Trauma Association classification) of the right knee of a forty three years old male patient. It was fixed with three vertical 1.5 mm K wires and double cerclage wire looped proximally through the quadriceps tendon and distally through the patellar ligament in a double figure-of-eight configuration. The average follow-up period was 7 months. The Activity of Daily Living Scale (ADLS) of the Knee Outcome Survey was used to assess symptoms and functional capability of the knee. The fracture union was achieved at an average of 10 weeks. Full range of knee motion was achieved by end of the third postoperative month. No complications, such as infection and implant failure were noted. The technique aims to stress the advantage of giving a balanced fixation addressing the bony elements (the fractured ends) as well as the soft tissue (the extensor apparatus).
文摘Introduction Endoscopic ultrasound-guided hepaticogastrostomy(EUS-HGS)is widely used;however,it may be associated with adverse events(AEs),such as stent migration,bleeding,bile leakage,and bile peritonitis[1].Safer techniques are needed to improve patient outcomes and facilitate effective trainee education.
基金Supported by the National Natural Science Foundation of China(11671350,11571173,11801043)Natural Science Foundation for Youths of Jiangsu Province(BK20181031).
文摘As an improvement of the combinatorial realization of totally positive matrices via the essential positive weightings of certain planar network by S.Fomin and A.Zelevinsky[7],in this paper,we give a test method of positive definite matrices via the planar networks and the so-called mixing-type sub-cluster algebras respectively,introduced here originally.This work firstly gives a combinatorial realization of all matrices through planar network,and then sets up a test method for positive definite matrices by LDU-decompositions and the horizontal weightings of all lines in their planar networks.On the other hand,mainly the relationship is built between positive definite matrices and mixing-type sub-cluster algebras.
文摘The common vibration of cable caused by rain-wind combination has been known as most typical type and a lot kind of its countermeasures has been proposed for suppressing this phenomenon. Recently, stayed-cables were also proved that they could be excited in dry state （without rain）, which is called dry-galloping. Recently, its mechanisms have been explained by axial flow, Reynolds number and so on. To clarify the characteristics of this galloping, wind tunnel test of a cable model with various kinds of wind angle was conducted. Then, three types of countermeasure were examined to suppress dry- galloping of bridge cable. The tests confirmed that the occurrence of dry-galloping depends on relative wind attacked angles and onset reduced wind speed. Furthermore, single spiral wire, double spiral wire and circular ring were found to have high effectiveness in mitigating this galloping when those are installed properly.
