The relationship between salmon prices and attributes were explored using the samples collected in supermarkets in Shanghai,China.The results showed that the price of the salmon did not have a significant relationship...The relationship between salmon prices and attributes were explored using the samples collected in supermarkets in Shanghai,China.The results showed that the price of the salmon did not have a significant relationship with the depth of orange color of salmon,unlike the results of stated preferences of western consumers in the previous studies.Whereas,smoked products had a positive relationship with price in the linear model form,and as the main importing country,Norway has the strongest positive relationship with price.In China salmon demand is expected to increase in future,salmon attributes highly appreciated in the market are different from western countries and salmon exporters need to recognize China as a special market for effective market.展开更多
The assembly quality of the tube system,which serves as the“blood vessels”and“trachea”of the aircraft,has a crucial impact on the stable and reliable service of aircraft.At present,the tightening control method of...The assembly quality of the tube system,which serves as the“blood vessels”and“trachea”of the aircraft,has a crucial impact on the stable and reliable service of aircraft.At present,the tightening control method of the tube system is mainly the torque control method,which exhibits considerable discreteness and has difficulty achieving precise control of the assembly quality.This paper constructed a torque-angle tightening control model based on the torque–force relationship and angle-force relationship of aviation tube systems.Through tightening experiments with five tube diameters,the initial tightening degree,re-tightening operation,lubrication condition,tube material,and connector material were investigated by comparing the torque-angle tightening curves.Results showed that the re-tightening operation can increase the tightening torque by at least%,the lubrication condition can reduce the target torque by about 16%,and the control angle range can be reduced by about 10°.Further theoretical and experimental analysis revealed that the system stiffness remained stable at 90000N/mm when the tube diameter was greater than mm.The torque–tension coefficient remained stable at around 0.16,while the angle-tension coefficient gradually decreased with the increase in the tube diameter.展开更多
文摘The relationship between salmon prices and attributes were explored using the samples collected in supermarkets in Shanghai,China.The results showed that the price of the salmon did not have a significant relationship with the depth of orange color of salmon,unlike the results of stated preferences of western consumers in the previous studies.Whereas,smoked products had a positive relationship with price in the linear model form,and as the main importing country,Norway has the strongest positive relationship with price.In China salmon demand is expected to increase in future,salmon attributes highly appreciated in the market are different from western countries and salmon exporters need to recognize China as a special market for effective market.
文摘The assembly quality of the tube system,which serves as the“blood vessels”and“trachea”of the aircraft,has a crucial impact on the stable and reliable service of aircraft.At present,the tightening control method of the tube system is mainly the torque control method,which exhibits considerable discreteness and has difficulty achieving precise control of the assembly quality.This paper constructed a torque-angle tightening control model based on the torque–force relationship and angle-force relationship of aviation tube systems.Through tightening experiments with five tube diameters,the initial tightening degree,re-tightening operation,lubrication condition,tube material,and connector material were investigated by comparing the torque-angle tightening curves.Results showed that the re-tightening operation can increase the tightening torque by at least%,the lubrication condition can reduce the target torque by about 16%,and the control angle range can be reduced by about 10°.Further theoretical and experimental analysis revealed that the system stiffness remained stable at 90000N/mm when the tube diameter was greater than mm.The torque–tension coefficient remained stable at around 0.16,while the angle-tension coefficient gradually decreased with the increase in the tube diameter.
