Research and modeling of tire cornering characteristics considering temperature based on UniTire model

Author(s):  
Lei Lu ◽  
Dang Lu ◽  
Haidong Wu ◽  
Wei Wang ◽  
Lun Li ◽  
...  

Based on the results of tire handling test, the cornering properties of the tire at small side slip under different temperature are obtained, and the variation law of the parameters of tire cornering characteristic with the temperature is obtained. By establishing a tread temperature model and finite element tire model considering the influence of temperature, the mechanism of tire mechanical properties with temperature is clarified, and the expression of tread stiffness and aligning stiffness considering temperature is obtained. Then, based on the above expression and the tire mechanical characteristics with temperature, a complex brush model is established and the relationship between the temperature and the tire cornering properties is obtained. The relationship is used as the basic expression formula to establish the UniTire cornering model considering tire temperature. In order to verify the correctness of the model, four kinds of temperature state cornering data are used for parameter identification, and the tire cornering properties in the other two temperature states is predicted. The error between the simulation results of the prediction model and the experimental results is very small, which effectively proves the predictive ability of the UniTire cornering model considering tire temperature. This research is helpful to improve the application of UniTire model under different temperature condition.

2020 ◽  
Author(s):  
Dang Lu ◽  
Lei Lu ◽  
HaiDong Wu ◽  
Lun Li ◽  
Wei Wang ◽  
...  

Abstract Based on the results of tire handling test, the cornering properties of the tire at a small range of steer angles under different temperature are obtained, and the variation law of the tire cornering characteristic parameters with the tire temperature is obtained. By establishing a tread temperature model and finite element tire model considering temperature, the mechanism of tire mechanical properties with temperature is clarified, and the expression of tread stiffness and aligning stiffness considering temperature is obtained. Then, based on the above expression and the tire brush model considering the tire temperature state, a complex brush model is established. Through the model derivation, the relationship between the temperature and the tire cornering stiffness is obtained. The relationship is used as the basic expression formula to establish the UniTire cornering model considering tire temperature. In order to verify the correctness of the model, four kinds of temperature state cornering data are used for parameter identification, and the tire cornering properties in the other two temperature states is predicted. The error between the simulation results of the prediction model and the experimental results is very small, which effectively proves the predictive ability of the UniTire cornering model considering tire temperature. This research is helpful to improve the application of UniTire model, and provide theoretical and technical support for UniTire model indoor and outdoor expansion applications


2016 ◽  
Vol 41 ◽  
pp. 1660143 ◽  
Author(s):  
R. V. Davydov ◽  
V. I. Antonov ◽  
T. I. Davydova

In this paper a mathematical model for femtosecond laser ablation of metals is proposed, based on standard two-temperature model connected with 1D hydrodynamic equations. Wide-range equation of state has been developed. The simulation results are compared with experimental data for aluminium and copper. A good agreement for both metals with numerical results and experiment shows that this model can be employed for choosing laser parameters to better accuracy in nanoparticles production by ablation of metals.


2018 ◽  
Author(s):  
Meng An ◽  
Qichen Song ◽  
Xiaoxiang Yu ◽  
Han Meng ◽  
Dengke Ma ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pierre Nouvellet ◽  
Sangeeta Bhatia ◽  
Anne Cori ◽  
Kylie E. C. Ainslie ◽  
Marc Baguelin ◽  
...  

AbstractIn response to the COVID-19 pandemic, countries have sought to control SARS-CoV-2 transmission by restricting population movement through social distancing interventions, thus reducing the number of contacts. Mobility data represent an important proxy measure of social distancing, and here, we characterise the relationship between transmission and mobility for 52 countries around the world. Transmission significantly decreased with the initial reduction in mobility in 73% of the countries analysed, but we found evidence of decoupling of transmission and mobility following the relaxation of strict control measures for 80% of countries. For the majority of countries, mobility explained a substantial proportion of the variation in transmissibility (median adjusted R-squared: 48%, interquartile range - IQR - across countries [27–77%]). Where a change in the relationship occurred, predictive ability decreased after the relaxation; from a median adjusted R-squared of 74% (IQR across countries [49–91%]) pre-relaxation, to a median adjusted R-squared of 30% (IQR across countries [12–48%]) post-relaxation. In countries with a clear relationship between mobility and transmission both before and after strict control measures were relaxed, mobility was associated with lower transmission rates after control measures were relaxed indicating that the beneficial effects of ongoing social distancing behaviours were substantial.


1989 ◽  
Vol 19 (1) ◽  
pp. 57-68 ◽  
Author(s):  
Lee N. Robins

SynopsisThere has been concern about whether standardized psychiatric interviews make valid diagnoses. Agreements between the Diagnostic Interview Schedule (DIS), as an example of a standardized interview, with independent assessments by a clinician are reasonably high in most studies, but the clinical assessment is itself of uncertain validity. Using predictive ability is an alternative way of judging validity. Data are presented to show that the DIS is almost as good at prediction as a clinician's assessment, but here too there are problems. Because prediction is probabilistic (i.e. the same disorder can have multiple outcomes, and different disorders can share outcomes), it is not possible to say how good prediction has to be to demonstrate perfect validity.Across varied methods of validity assessment, some disorders are regularly found more validly diagnosed than others, suggesting that part of the source of invalidity lies in the diagnostic grammar of the systems whose criteria standardized interviews evaluate. Sources of invalidity inherent in the content and structure of a variety of diagnoses in DSM-III and its heir, DSM-III-R, are reviewed and illustrated, in part with results from the Epidemiological Catchment Area study.The relationship between diagnostic criteria and standardized interviews is symbiotic. While attempts to adhere closely to existing diagnostic criteria contribute to the diagnostic accuracy of standardized interviews, the exercise of translating official diagnostic criteria into standardized questions highlights problems in the system's diagnostic grammar, enabling standardized interviews to contribute to improvements in diagnostic nosology.


2015 ◽  
Vol 645-646 ◽  
pp. 70-74 ◽  
Author(s):  
Min Zhong ◽  
Yu Hang Zhao ◽  
Shou Mian Chen ◽  
Ming Li ◽  
Shao Hai Zeng ◽  
...  

An embedded SiGe layer was applied in the source/drain areas (S/D) of a field-effect transistor to boost the performance in the p channels. Raised SiGe S/D plays a critical role in strain engineering. In this study, the relationship between the SiGe overfilling and the enhancement of channel stress was investigated. Systematic technology computer aided design (TCAD) simulations of the SiGe overfill height in a 40 nm PMOS were performed. The simulation results indicate that a moderate SiGe overfilling induces the highest stress in the channel. Corresponding epitaxial growth experiments were done and the obtained experimental data was in good agreement with the simulation results. The effect of the SiGe overfilling is briefly discussed. The results and conclusions presented within this paper might serve as useful references for the optimization of the embedded SiGe stressor for 40 nm logic technology node and beyond.


2004 ◽  
Vol 2004 (IAUS226) ◽  
pp. 506-510
Author(s):  
J. H. Guo ◽  
Y. Li ◽  
H. G. Shan

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 3043 ◽  
Author(s):  
Weike Zhang ◽  
Xi Chen ◽  
Kaibo Cui ◽  
Tao Xie ◽  
Naichang Yuan

In order to improve the angle measurement performance of a coprime linear array, this paper proposes a novel direction-of-arrival (DOA) estimation algorithm for a coprime linear array based on the multiple invariance estimation of signal parameters via rotational invariance techniques (MI-ESPRIT) and a lookup table method. The proposed algorithm does not require a spatial spectrum search and uses a lookup table to solve ambiguity, which reduces the computational complexity. To fully use the subarray elements, the DOA estimation precision is higher compared with existing algorithms. Moreover, the algorithm avoids the matching error when multiple signals exist by using the relationship between the signal subspace of two subarrays. Simulation results verify the effectiveness of the proposed algorithm.


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