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During the torque phase, appropriate coordination between two clutches is of vital importance to the dual-clutch transmission so that a high-quality shift is achieved without clutch interaction and engine flare, because a poor-quality shift definitely extends the shift time and increases the friction work. Concerning this problem, two different power flow conditions during the torque phase are discussed in detail, after investigation of the dual-clutch transmission downshift process and the design of an H∞ robust controller for the inertia phase. The results obtained indicate that, if two clutches are slipping simultaneously during the torque phase, either power interruption or power circulation occurs. Thus, by optimizing the relationship between the two clutches, a novel control strategy is proposed for the dual-clutch transmission so that the downshift process is accomplished with only one slipping clutch, in order to obtain the highest system efficiency. The system model was established on the MATLAB/Simulink platform and used to study the variations in the torque and the speed output in response to different control strategies. The simulation results show that, with the smooth inertia phase guaranteed by the robust controller, the proposed control strategy not only can avoid power interruption or power circulation during the torque phase but also can shorten the shift time (from 1.1 s to 0.8 s) and reduce the jerk level (from 6.8 m/s3 to 5.7 m/s3) effectively, in comparison with the conventional control strategy. Finally, to validate the effectiveness of the proposed control strategy, bench tests on a dual-clutch transmission were carried out, and the test data obtained show good agreement with the simulation results.

International audienceIn 2011, Li presented clockwise collision analysis on nonprotected Advanced Encryption Standard (AES) hardware implementation. In this brief, we first propose a new clockwise collision attack, called fault rate analysis (FRA), on masked AES. Then, we analyze the critical and noncritical paths of the S-box and find that, for its three input bytes, namely, the input value, the input mask, and the output mask, the path relating to the output mask is much shorter than those relating to the other two inputs. Therefore, some sophisticated glitch cycles can be chosen such that the values in the critical path of the whole S-box are destroyed but this short path is not affected. As a result, the output mask does not offer protection to the S-box, which leads to a more efficient attack. Compared with three attacks on masking countermeasures at the Workshop on Cryptographic Hardware and Embedded Systems 2010 and 2011, our method only costs about 8% of their time and 4% of their storage space

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Based on the electrochemical and thermal model, a coupled electro-thermal runaway model was developed and implemented using finite element methods. The thermal decomposition reactions when the battery temperature exceeds the material decomposition temperature were embedded into the model. The temperature variations of a lithium titanate battery during a series of charge-discharge cycles under different current rates were simulated. The results of temperature and heat generation rate demonstrate that the greater the current, the faster the battery temperature is rising. Furthermore, the thermal influence of the overheated cell on surrounding batteries in the module was simulated, and the variation of temperature and heat generation during thermal runaway was obtained. It was found that the overheated cell can induce thermal runaway in other adjacent cells within 3 mm distance in the battery module if the accumulated heat is not dissipated rapidly.