No abstract

In this paper, a macroslip detection method is proposed for a metal V-belt continuously variable transmission, and a clamping force control strategy is suggested on the basis of a macroslip detection method. Using the rotational accelerations of the primary and secondary pulleys, the velocity of the secondary pulley and the speed ratio of the continuously variable transmission variator, observation signals are defined. The characteristics of the observation signals are investigated by simulations in a vehicle-driving environment. It is found that two observation signals became unsynchronized when macroslip occurs. Considering the oscillations of the acceleration signal and the noise from the sensors or the differentiating process, a signal-processing method for the observation signals is suggested. Based on the signal-processing results, a variable called the ‘amplitude difference rate’ is introduced for slip evaluation. A macroslip detection method that uses the amplitude difference rate is proposed. The effectiveness of the macroslip detection method is validated by experiments. It is found from the experiments that the proposed method can effectively detect macroslip with an acceptable time delay. In addition, a clamping force control strategy based on the macroslip detection method is developed. In this strategy, the clamping force is maintained at a minimum value with a safety factor of 1 in normal driving conditions but an additional clamping force is applied when macroslip is detected. It is found from the simulation results that macroslip is eliminated by clamping force control. It is expected that the efficiency of the continuously variable transmission system can be improved by reducing the marginal clamping force using the proposed macroslip detection method and the clamping force control strategy.

No abstract

Glioma accounts for 80% of all malignant brain tumours and is the most common adult primary brain tumour. Age is an important factor affecting the development of cancer, as somatic mutations accumulate with age. Here, we aimed to analyse the significance of age-dependent non-silent somatic mutations in glioma prognosis. Histological tumour grade depends on age at diagnosis in patients with IDH1, TP53, ATRX, and EGFR mutations. Age of patients with wild-type IDH1 and EGFR increased with increase in tumour grade, while the age of patients with IDH1 or EGFR mutation remained constant. However, the age of patients with EGFR mutation was higher than that of patients with IDH1 mutation. The hierarchical clustering of patients was dominantly separated by IDH1 and EGFR mutations. Furthermore, patients with IDH1 mutation were dominantly separated by TP53 and ATRX double mutation and its double wild-type counterpart. The age of patients with ATRX and TP53 mutation was lower than that of patients with wild-type ATRX and TP53. Patients with the double mutation showed poorer prognosis than those with the double wild type genotype. Unlike IDH1 mutant, IDH1 wild-type showed upregulation of expression of epithelial mesenchymal transition associated genes.