Friction and lubrication simulation analysis of internal combustion engine bearings are studied. A series of software implementary precepts for mathematical modeling, to analytic calculating and realizing simulation o...Friction and lubrication simulation analysis of internal combustion engine bearings are studied. A series of software implementary precepts for mathematical modeling, to analytic calculating and realizing simulation outcome are brought forward. As a dynamic simulating technique is introduced into the process of engine bearing design, simulation models of the oil film are built and the emulational analysis of the shaft center track is carried out. A software program package “Engine Bearing Friction and Lubrication Dynamic Simulation System” is developed to realize the real time simulation of the working status of bearing during the design process. Through developing virtualized products, the defects of the product design can be found in time and improve the products at once. Thus the purpose of predicting and controlling the cost, quality and design period of the products can be achieved.展开更多
A new method based on cross-spectrum estimation for the verification and validation of computer simulation models is expounded in accordance with the characteristics of missile systems. The new method can expose the d...A new method based on cross-spectrum estimation for the verification and validation of computer simulation models is expounded in accordance with the characteristics of missile systems. The new method can expose the differences between two time processes in several aspects and can also give quantitative analysis results about the statistical consistence between them. An application to an actual anti-tank missile system simulation is presented and the calculated results confirm the effectiveness of the method. The approach can also be employed to verify the simulation models of other dynamic systems.展开更多
In order to better study the dynamic characteristics and the control strategy of parafoil systems,considering the effect of flap deflection as the control mechanism and regarding the parafoil and the payload as a rigi...In order to better study the dynamic characteristics and the control strategy of parafoil systems,considering the effect of flap deflection as the control mechanism and regarding the parafoil and the payload as a rigid body,a six degrees-of-freedom(DOF)dynamic model of a parafoil system including three DOF for translational motion and three DOF for rotational motion,is established according to the K rchhoff motion equation.Since the flexible winged paafoil system flying at low altitude is more susceptibleto winds,the motion characteristics of the parafoil system Wth and Wthout winds are simulated and analyzed.Furthermore,the ardropm test is used to further verify the model.The comparison results show that the simulation trajectory roughly overlaps with the actual flight track.The horzontnl velocity of the simulation model is in good accordance with the airdrop test,with a deviation less than0.5m/s,while its simulated vertical velocity fuctuates slightly under the infuence of the wind,and shows a similar trend to the ardrop test.It is concludedthat the established model can well describe the characteristics of the parafoil system.展开更多
This paper conducts an analysis of HP model of a memristor and memory cells of a differential type memristor,formsa classic array of the memristor using the HP model,and does the stimulation of its storage capacity.Ba...This paper conducts an analysis of HP model of a memristor and memory cells of a differential type memristor,formsa classic array of the memristor using the HP model,and does the stimulation of its storage capacity.Based on differential typememristor cells,this paper proposes an improved crossbar array of the memristor,which can be applied in image storage.Bymeans of theoretical analysis and stimulation,this improved crossbar array of memristor has been proved to have bettergrayscale image storage capacity,and its peak signal-to-noise ratio(PSNR)has been improved by about30%.展开更多
The epidermal growth factor receptor(EGFR)—tyrosine kinase inhibitors(TKIs) monotherapies have limited efficacy in the treatment of EGFR mutation-negative non-small cell lung cancers(NSCLCs). In the present stu...The epidermal growth factor receptor(EGFR)—tyrosine kinase inhibitors(TKIs) monotherapies have limited efficacy in the treatment of EGFR mutation-negative non-small cell lung cancers(NSCLCs). In the present study, we aimed to investigate the combined effect of erlotinib(ER) and cabozantinib(CAB) on NSCLC cell lines harboring wild-type EGFR and to optimize the dosage regimens using pharmacodynamic(PD) modeling and simulation. Therefore, we examined the combined effect of ER and CAB on cell viability, cloning, apoptosis induction, migration and growth dynamics in H1299 and A549 cells. PD modeling and simulation were also performed to quantitatively describe the H1299 cells growth dynamics and to optimize the dosage regimens as well. Our results showed that CAB effectively enhanced the sensitivity of both cell lines to ER. The PD models fitted the data well, and some important parameters were obtained. The exponential(λ_0) and linear(λ_1) growth rates of H1299 cells were 0.0241 h^(–1) and 360 cells?h^(–1), respectively. The Emax of ER and CAB was 0.0091 h^(–1) and 0.0085 h^(–1), and the EC50 was 0.812 μM and 1.16 μM, respectively. The synergistic effect observed in the experiments was further confirmed by the estimated combination index φ(1.37),(95% confidence interval: 1.24–1.50), obtained from PD modeling. Furthermore, the dosage regimens were optimized using simulations. In summary, both the experimental and modeling results demonstrated the synergistic interaction between ER and CAB in NSCLCs without EGFR mutations. Sequential combinations of ER and CAB provided an option for the therapy of the NSCLCs with wild-type EGFR, which would provide some references for preclinical study and translational research as well.展开更多
文摘Friction and lubrication simulation analysis of internal combustion engine bearings are studied. A series of software implementary precepts for mathematical modeling, to analytic calculating and realizing simulation outcome are brought forward. As a dynamic simulating technique is introduced into the process of engine bearing design, simulation models of the oil film are built and the emulational analysis of the shaft center track is carried out. A software program package “Engine Bearing Friction and Lubrication Dynamic Simulation System” is developed to realize the real time simulation of the working status of bearing during the design process. Through developing virtualized products, the defects of the product design can be found in time and improve the products at once. Thus the purpose of predicting and controlling the cost, quality and design period of the products can be achieved.
文摘A new method based on cross-spectrum estimation for the verification and validation of computer simulation models is expounded in accordance with the characteristics of missile systems. The new method can expose the differences between two time processes in several aspects and can also give quantitative analysis results about the statistical consistence between them. An application to an actual anti-tank missile system simulation is presented and the calculated results confirm the effectiveness of the method. The approach can also be employed to verify the simulation models of other dynamic systems.
基金The National Natural Science Foundation of China(No.61273138,61573197)the National Key Technology R&D Program(No.2015BAK06B04)+1 种基金the Key Fund of Tianjin(No.14JCZDJC39300)the Key Technologies R&D Program of Tianjin(No.14ZCZDSF00022)
文摘In order to better study the dynamic characteristics and the control strategy of parafoil systems,considering the effect of flap deflection as the control mechanism and regarding the parafoil and the payload as a rigid body,a six degrees-of-freedom(DOF)dynamic model of a parafoil system including three DOF for translational motion and three DOF for rotational motion,is established according to the K rchhoff motion equation.Since the flexible winged paafoil system flying at low altitude is more susceptibleto winds,the motion characteristics of the parafoil system Wth and Wthout winds are simulated and analyzed.Furthermore,the ardropm test is used to further verify the model.The comparison results show that the simulation trajectory roughly overlaps with the actual flight track.The horzontnl velocity of the simulation model is in good accordance with the airdrop test,with a deviation less than0.5m/s,while its simulated vertical velocity fuctuates slightly under the infuence of the wind,and shows a similar trend to the ardrop test.It is concludedthat the established model can well describe the characteristics of the parafoil system.
基金Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi Province(No.20151101)Shanxi Key R&D Plan(No.2016-40-2)+1 种基金Innovative Training Program for College Students in Shanxi Province(No.2016481)Natural Science Foundation of Shanxi Province(No.201701D121067)
文摘This paper conducts an analysis of HP model of a memristor and memory cells of a differential type memristor,formsa classic array of the memristor using the HP model,and does the stimulation of its storage capacity.Based on differential typememristor cells,this paper proposes an improved crossbar array of the memristor,which can be applied in image storage.Bymeans of theoretical analysis and stimulation,this improved crossbar array of memristor has been proved to have bettergrayscale image storage capacity,and its peak signal-to-noise ratio(PSNR)has been improved by about30%.
基金National Natural Science Foundation of China(NSFC,Grant No.81273583)
文摘The epidermal growth factor receptor(EGFR)—tyrosine kinase inhibitors(TKIs) monotherapies have limited efficacy in the treatment of EGFR mutation-negative non-small cell lung cancers(NSCLCs). In the present study, we aimed to investigate the combined effect of erlotinib(ER) and cabozantinib(CAB) on NSCLC cell lines harboring wild-type EGFR and to optimize the dosage regimens using pharmacodynamic(PD) modeling and simulation. Therefore, we examined the combined effect of ER and CAB on cell viability, cloning, apoptosis induction, migration and growth dynamics in H1299 and A549 cells. PD modeling and simulation were also performed to quantitatively describe the H1299 cells growth dynamics and to optimize the dosage regimens as well. Our results showed that CAB effectively enhanced the sensitivity of both cell lines to ER. The PD models fitted the data well, and some important parameters were obtained. The exponential(λ_0) and linear(λ_1) growth rates of H1299 cells were 0.0241 h^(–1) and 360 cells?h^(–1), respectively. The Emax of ER and CAB was 0.0091 h^(–1) and 0.0085 h^(–1), and the EC50 was 0.812 μM and 1.16 μM, respectively. The synergistic effect observed in the experiments was further confirmed by the estimated combination index φ(1.37),(95% confidence interval: 1.24–1.50), obtained from PD modeling. Furthermore, the dosage regimens were optimized using simulations. In summary, both the experimental and modeling results demonstrated the synergistic interaction between ER and CAB in NSCLCs without EGFR mutations. Sequential combinations of ER and CAB provided an option for the therapy of the NSCLCs with wild-type EGFR, which would provide some references for preclinical study and translational research as well.