We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuratio...We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.展开更多
In the process of spectrum perception,in order to realize accurate perception of the channel state,the method of multi-node cooperative perception can usually be used.However,the first problem to be considered is how ...In the process of spectrum perception,in order to realize accurate perception of the channel state,the method of multi-node cooperative perception can usually be used.However,the first problem to be considered is how to complete information fusion and obtain more accurate and reliable judgment results based on multi-node perception results.The ideas put forward in this paper are as follows:firstly,the perceived results of each node are obtained on the premise of limiting detection probability and false alarm probability.Then,on the one hand,the weighted fusion criterion of decision-making weight optimization of each node is realized based on a genetic algorithm,and the useless nodes also can be screened out to reduce energy loss;on the other hand,through the linear fitting ability of RBF neural network,the self-inspection of the perceptive nodes can be realized to ensure the normal operation of the perceptive work of each node.What's more,the real-time training data can be obtained by spectral segmentation technology to ensure the real-time accuracy of the optimization results.Finally,the simulation results show that this method can effectively improve the accuracy and stability of channel perception results,optimize the structure of the cooperative network and reduce energy consumption.展开更多
Rolling element bearing is the most common machine element in rotating machinery.An extended life is among the foremost imperative standards in the optimal design of rolling element bearings,which confide on the fatig...Rolling element bearing is the most common machine element in rotating machinery.An extended life is among the foremost imperative standards in the optimal design of rolling element bearings,which confide on the fatigue failure,wear,and thermal conditions of bearings.To fill the gap,in the current work,all three objectives of a tapered roller bearing have been innovatively considered respectively,which are the dynamic capacity,elasto-hydrodynamic lubrication(EHL)minimum film⁃thickness,and maximum bearing temperature.These objective function formulations are presented,associated design variables are identified,and constraints are discussed.To solve complex non⁃linear constrained optimization formulations,a best⁃practice design procedure was investigated using the Artificial Bee Colony(ABC)algorithms.A sensitivity analysis of several geometric design variables was conducted to observe the difference in all three objectives.An excellent enhancement was found in the bearing designs that have been optimized as compared with bearing standards and previously published works.The present study will definitely add to the present experience based design followed in bearing industries to save time and obtain assessment of bearing performance before manufacturing.To verify the improvement,an experimental investigation is worthwhile conducting.展开更多
The lightning protection design of "Feilongzaitian" roller coaster of Fangte in Zigong was discussed, and the lightning protection measures of "Feilongzaitian" roller coaster were analyzed from the...The lightning protection design of "Feilongzaitian" roller coaster of Fangte in Zigong was discussed, and the lightning protection measures of "Feilongzaitian" roller coaster were analyzed from the aspects of direct lightning protection, grounding and lightning electromagnetic impulse protection.展开更多
The article presents a structural diagram and the principle of operation of the installation of a sewing machine for applying a polymer composition to the stitch lines of tarpaulin materials. The calculation schemes a...The article presents a structural diagram and the principle of operation of the installation of a sewing machine for applying a polymer composition to the stitch lines of tarpaulin materials. The calculation schemes and the mathematical model of oscillations of the axis of the composite roller during the application of the polymer composition along the lines of tarpaulin materials are presented. Based on the numerical solution of the problem, the regularities of roller oscillations are presented. The main parameters of the system are substantiated.展开更多
文摘We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.
文摘In the process of spectrum perception,in order to realize accurate perception of the channel state,the method of multi-node cooperative perception can usually be used.However,the first problem to be considered is how to complete information fusion and obtain more accurate and reliable judgment results based on multi-node perception results.The ideas put forward in this paper are as follows:firstly,the perceived results of each node are obtained on the premise of limiting detection probability and false alarm probability.Then,on the one hand,the weighted fusion criterion of decision-making weight optimization of each node is realized based on a genetic algorithm,and the useless nodes also can be screened out to reduce energy loss;on the other hand,through the linear fitting ability of RBF neural network,the self-inspection of the perceptive nodes can be realized to ensure the normal operation of the perceptive work of each node.What's more,the real-time training data can be obtained by spectral segmentation technology to ensure the real-time accuracy of the optimization results.Finally,the simulation results show that this method can effectively improve the accuracy and stability of channel perception results,optimize the structure of the cooperative network and reduce energy consumption.
文摘Rolling element bearing is the most common machine element in rotating machinery.An extended life is among the foremost imperative standards in the optimal design of rolling element bearings,which confide on the fatigue failure,wear,and thermal conditions of bearings.To fill the gap,in the current work,all three objectives of a tapered roller bearing have been innovatively considered respectively,which are the dynamic capacity,elasto-hydrodynamic lubrication(EHL)minimum film⁃thickness,and maximum bearing temperature.These objective function formulations are presented,associated design variables are identified,and constraints are discussed.To solve complex non⁃linear constrained optimization formulations,a best⁃practice design procedure was investigated using the Artificial Bee Colony(ABC)algorithms.A sensitivity analysis of several geometric design variables was conducted to observe the difference in all three objectives.An excellent enhancement was found in the bearing designs that have been optimized as compared with bearing standards and previously published works.The present study will definitely add to the present experience based design followed in bearing industries to save time and obtain assessment of bearing performance before manufacturing.To verify the improvement,an experimental investigation is worthwhile conducting.
文摘The lightning protection design of "Feilongzaitian" roller coaster of Fangte in Zigong was discussed, and the lightning protection measures of "Feilongzaitian" roller coaster were analyzed from the aspects of direct lightning protection, grounding and lightning electromagnetic impulse protection.
文摘The article presents a structural diagram and the principle of operation of the installation of a sewing machine for applying a polymer composition to the stitch lines of tarpaulin materials. The calculation schemes and the mathematical model of oscillations of the axis of the composite roller during the application of the polymer composition along the lines of tarpaulin materials are presented. Based on the numerical solution of the problem, the regularities of roller oscillations are presented. The main parameters of the system are substantiated.
