Based on the experimental results of the references [1] and [2], i. e., the contact resistance increases due to the contaminants formed on contact surface with the operating cycles,the physical model and math model of...Based on the experimental results of the references [1] and [2], i. e., the contact resistance increases due to the contaminants formed on contact surface with the operating cycles,the physical model and math model of contact failure on small current contacts under mechanical actions are proposed through deep theoretical analysis in this paper.展开更多
The linear and non-linear math models of the switched reluctance generator (SRG) in generator mode were established in this work. The phase current and energy conversion process during generator operation were simulat...The linear and non-linear math models of the switched reluctance generator (SRG) in generator mode were established in this work. The phase current and energy conversion process during generator operation were simulated by the linear math model. The non-linear math model was used to analyze the characteristics of the SRG operation in self-excitation mode and in separately-excitation mode. Some important findings on how the SRG is operated and controlled were obtained in this study, which provides theoretical basis for further design and experimental study.展开更多
During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply ...During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply trial calculation method and graphic method,and improve the calculate precision,the mathematical model has been built up,the writer combines example to explain the train of thought,the result shows that the calculation precision is high,the correctness is tested and verified by the result which is calculated by hand.It can be referred to the hydroelectric works.展开更多
Providing comfortable indoor air quality control in residential construction is an exceedingly important issue.This is due to the structure of the fast response controller of air quality.The presented work shows the b...Providing comfortable indoor air quality control in residential construction is an exceedingly important issue.This is due to the structure of the fast response controller of air quality.The presented work shows the breakdown and creation of a mathematical model for an interactive,nonlinear system for the required comfortable air quality.Furthermore,the paper refers to designing traditional proportional integral derivative regulators and proportional,integral,derivative regulators with independent parameters based on a backpropagation neural network.In the end,we perform the experimental outputs of a suggested backpropagation neural network-based proportional,integral,derivative controller and analyze model results by applying the proposed system.The obtained results demonstrated that the proposed controller can provide the required level of clean air in the room.The proposed developed model takes into consideration international Heating,Refrigerating,and air conditioning standards as ASHRAE AND ISO.Based on the findings,we concluded that it is possible to implement a proposed system in homes and offer equivalent indoor air quality with continuous mechanical ventilation without a profuse amount of energy.展开更多
Realistic 3D-animation is used in all motion simulation systems of mechanisms and other mechanicals systems. It provides a high-quality illustration of time processes, but it has a weak capability for analysis of thei...Realistic 3D-animation is used in all motion simulation systems of mechanisms and other mechanicals systems. It provides a high-quality illustration of time processes, but it has a weak capability for analysis of their dynamics, for simultaneous display of contact interaction and functioning of mechanisms of different motion types. A spacecraft docking is characterized by a complex contact interaction of docking assemblies with mechanisms and devices of different motion types. Integration and time synchronization of the animation, plots and numerical values greatly facilitates the understanding of dynamics features of these processes. Usage of simple wireframe graphical models allows displaying all contact points. A changing of the set of graphical elements focuses attention on major events of a simulated process. Graphical models developed with consideration of these features and used for spacecraft docking simulation analysis are called dynamic diagrams and described in this paper.展开更多
MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler is introduced to research the relations be-tween thickness of UHMWPE’s wear debris and positive pressure of tribological system.Research re-sults show that thic...MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler is introduced to research the relations be-tween thickness of UHMWPE’s wear debris and positive pressure of tribological system.Research re-sults show that thickness of wear debris owns evident classification,and the first grade thickness math model and the second grade thickness math model are built.By the second grade thickness math model,the true force condition in the tribological system can be gotten,and the model can be used as a tool to modify simulating parameters of the tribological system,and it is an important inspecting method to the airtight system which cannot be examined in real time.The first grade thickness math model can describe the true working load and surface condition of work piece in the tribological sys-tem,and is an effective description method for the running condition of frictional pairs.The research results at different lubricating conditions testify the relations between thicknesses of wear debris and positive pressure of the tribological system.The fractal relation between maximal thickness of wear debris and positive pressure is discussed.The conceptions of the immutability principle and charac-teristic granularity of wear debris thickness are brought forward and discussed.In conclusion,as a stable tribological parameter owning mechanical theory basis,wear debris thickness will play an im-portant part in fault diagnosis,especially for the airtight system such as artificial joint.展开更多
文摘Based on the experimental results of the references [1] and [2], i. e., the contact resistance increases due to the contaminants formed on contact surface with the operating cycles,the physical model and math model of contact failure on small current contacts under mechanical actions are proposed through deep theoretical analysis in this paper.
文摘The linear and non-linear math models of the switched reluctance generator (SRG) in generator mode were established in this work. The phase current and energy conversion process during generator operation were simulated by the linear math model. The non-linear math model was used to analyze the characteristics of the SRG operation in self-excitation mode and in separately-excitation mode. Some important findings on how the SRG is operated and controlled were obtained in this study, which provides theoretical basis for further design and experimental study.
文摘During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply trial calculation method and graphic method,and improve the calculate precision,the mathematical model has been built up,the writer combines example to explain the train of thought,the result shows that the calculation precision is high,the correctness is tested and verified by the result which is calculated by hand.It can be referred to the hydroelectric works.
文摘Providing comfortable indoor air quality control in residential construction is an exceedingly important issue.This is due to the structure of the fast response controller of air quality.The presented work shows the breakdown and creation of a mathematical model for an interactive,nonlinear system for the required comfortable air quality.Furthermore,the paper refers to designing traditional proportional integral derivative regulators and proportional,integral,derivative regulators with independent parameters based on a backpropagation neural network.In the end,we perform the experimental outputs of a suggested backpropagation neural network-based proportional,integral,derivative controller and analyze model results by applying the proposed system.The obtained results demonstrated that the proposed controller can provide the required level of clean air in the room.The proposed developed model takes into consideration international Heating,Refrigerating,and air conditioning standards as ASHRAE AND ISO.Based on the findings,we concluded that it is possible to implement a proposed system in homes and offer equivalent indoor air quality with continuous mechanical ventilation without a profuse amount of energy.
文摘Realistic 3D-animation is used in all motion simulation systems of mechanisms and other mechanicals systems. It provides a high-quality illustration of time processes, but it has a weak capability for analysis of their dynamics, for simultaneous display of contact interaction and functioning of mechanisms of different motion types. A spacecraft docking is characterized by a complex contact interaction of docking assemblies with mechanisms and devices of different motion types. Integration and time synchronization of the animation, plots and numerical values greatly facilitates the understanding of dynamics features of these processes. Usage of simple wireframe graphical models allows displaying all contact points. A changing of the set of graphical elements focuses attention on major events of a simulated process. Graphical models developed with consideration of these features and used for spacecraft docking simulation analysis are called dynamic diagrams and described in this paper.
基金Supported by the Key Program of the National Natural Science Foundation of China(Grant No.50535050)the National Basic Research Development Program of China(Grant No.2007CB607605)
文摘MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler is introduced to research the relations be-tween thickness of UHMWPE’s wear debris and positive pressure of tribological system.Research re-sults show that thickness of wear debris owns evident classification,and the first grade thickness math model and the second grade thickness math model are built.By the second grade thickness math model,the true force condition in the tribological system can be gotten,and the model can be used as a tool to modify simulating parameters of the tribological system,and it is an important inspecting method to the airtight system which cannot be examined in real time.The first grade thickness math model can describe the true working load and surface condition of work piece in the tribological sys-tem,and is an effective description method for the running condition of frictional pairs.The research results at different lubricating conditions testify the relations between thicknesses of wear debris and positive pressure of the tribological system.The fractal relation between maximal thickness of wear debris and positive pressure is discussed.The conceptions of the immutability principle and charac-teristic granularity of wear debris thickness are brought forward and discussed.In conclusion,as a stable tribological parameter owning mechanical theory basis,wear debris thickness will play an im-portant part in fault diagnosis,especially for the airtight system such as artificial joint.
