Multi-frictional disks are employed to transmit the torque in speeding wetclutch, and the oil thickness within frictional disks could be adjusted for practical outputspeeding. As oil combined with alpha-hydrocarbon or...Multi-frictional disks are employed to transmit the torque in speeding wetclutch, and the oil thickness within frictional disks could be adjusted for practical outputspeeding. As oil combined with alpha-hydrocarbon or polyester is getting widely used as lubricantand the speeding wet clutch works within hydrodynamic lubrication, mixture lubrication, boundarylubrication and contact situation, established the thermal analysis model for investigating thebehavior of frictional disks in speeding wet clutch, which covers the power-law fluid model,Patir-Cheng average flow model, GT asperity contact model, oil film inertia and heat effects, meanenergy equation, and heat conduction equation. The formulas in the model are deduced. The numeralcalculation and analysis for hydrodynamic lubrication and mixture lubrication are executed.Relationships and variations among transmitting torque, mean push pressure, output speed, and loadare presented. Thermal effect should be considered during the hydrodynamic lubrication and largertransmitting torque makes earlier entrance to mixture lubrication.展开更多
The present research aimed to identify critical factors that affect speeding behavior.For that purpose,high-resolution smartphone data collected from a naturalistic driving experiment of 88 drivers were utilized,augme...The present research aimed to identify critical factors that affect speeding behavior.For that purpose,high-resolution smartphone data collected from a naturalistic driving experiment of 88 drivers were utilized,augmented with data from self-reported questionnaires.Using risk exposure and driving behavior indicators calculated from smartphone sensor data,as well as demographic characteristics and self-reported driving performance,statistical analysis was carried out for modelling the percentage of driving time over the speed limit,namely by means of generalized linear mixed-effects models.More precisely,an overall model was developed for all road environments,and additional separate models were developed for driving on urban and rural roads.The results from the interpretation of the estimated parameters of the models can be summarized as follows:the parameters of trip distance and mobile phone use while driving have been determined as statistically significant and positively correlated with the percentage of speeding time during a driver's trip.In the same context,male drivers and drivers in the age group of18-34 also increase the percentages of speeding instances while driving.Regarding driving behavior as stated on the questionnaire,it seems that low frequencies of self-declared speeding(never or rarely)are statistically significant and negatively correlated with the percentage of speeding time.It is expected that this research can provide considerable gains to society,since the stakeholders including policy makers and industry could rely on the results and recommendations regarding risk factors that appear to be critical for safe driving.展开更多
The spherical harmonic series expression of electromagnetic fields excited by ELF/SLF vertical electric dipole in the spherical earth-ionosphere cavity is derived when the earth and ionosphere are regarded as non-idea...The spherical harmonic series expression of electromagnetic fields excited by ELF/SLF vertical electric dipole in the spherical earth-ionosphere cavity is derived when the earth and ionosphere are regarded as non-ideal conductors.A method of speeding numerical convergence has been presented.The electromagnetic fields in the cavity are calculated by this algorithm,and the results show that the electromagnetic fields between the earth and the ionosphere are the sum of two traveling waves in the SLF band.Moreover,the results are in complete agreement with that of the well-known spherical second-order approximation in the SLF band.The electromagnetic fields in the cavity are a type of standing wave in the ELF band and the variation of the amplitude versus frequency coincides with Schumann’s resonance.展开更多
文摘Multi-frictional disks are employed to transmit the torque in speeding wetclutch, and the oil thickness within frictional disks could be adjusted for practical outputspeeding. As oil combined with alpha-hydrocarbon or polyester is getting widely used as lubricantand the speeding wet clutch works within hydrodynamic lubrication, mixture lubrication, boundarylubrication and contact situation, established the thermal analysis model for investigating thebehavior of frictional disks in speeding wet clutch, which covers the power-law fluid model,Patir-Cheng average flow model, GT asperity contact model, oil film inertia and heat effects, meanenergy equation, and heat conduction equation. The formulas in the model are deduced. The numeralcalculation and analysis for hydrodynamic lubrication and mixture lubrication are executed.Relationships and variations among transmitting torque, mean push pressure, output speed, and loadare presented. Thermal effect should be considered during the hydrodynamic lubrication and largertransmitting torque makes earlier entrance to mixture lubrication.
基金co-financed by the European Union-European Regional Development Fund (ERDF)and Greek national funds through the Operational Program“Competitiveness,Entrepreneurship and Innovation” (EPAnEK)of the National Strategic Reference Framework (NSRF)-Research Funding Program:BeSmart-multi-modal driver behavior and safety support system on the basis of smartphone applications。
文摘The present research aimed to identify critical factors that affect speeding behavior.For that purpose,high-resolution smartphone data collected from a naturalistic driving experiment of 88 drivers were utilized,augmented with data from self-reported questionnaires.Using risk exposure and driving behavior indicators calculated from smartphone sensor data,as well as demographic characteristics and self-reported driving performance,statistical analysis was carried out for modelling the percentage of driving time over the speed limit,namely by means of generalized linear mixed-effects models.More precisely,an overall model was developed for all road environments,and additional separate models were developed for driving on urban and rural roads.The results from the interpretation of the estimated parameters of the models can be summarized as follows:the parameters of trip distance and mobile phone use while driving have been determined as statistically significant and positively correlated with the percentage of speeding time during a driver's trip.In the same context,male drivers and drivers in the age group of18-34 also increase the percentages of speeding instances while driving.Regarding driving behavior as stated on the questionnaire,it seems that low frequencies of self-declared speeding(never or rarely)are statistically significant and negatively correlated with the percentage of speeding time.It is expected that this research can provide considerable gains to society,since the stakeholders including policy makers and industry could rely on the results and recommendations regarding risk factors that appear to be critical for safe driving.
文摘The spherical harmonic series expression of electromagnetic fields excited by ELF/SLF vertical electric dipole in the spherical earth-ionosphere cavity is derived when the earth and ionosphere are regarded as non-ideal conductors.A method of speeding numerical convergence has been presented.The electromagnetic fields in the cavity are calculated by this algorithm,and the results show that the electromagnetic fields between the earth and the ionosphere are the sum of two traveling waves in the SLF band.Moreover,the results are in complete agreement with that of the well-known spherical second-order approximation in the SLF band.The electromagnetic fields in the cavity are a type of standing wave in the ELF band and the variation of the amplitude versus frequency coincides with Schumann’s resonance.