A Method to Develop the Driver-Adaptive Lane-Keeping Assistance System Based on Real Driver Preferences.

To satisfy the preference of each driver, the development of a Lane-Keeping Assistance (LKA) system that can adapt to individual drivers has become a research hotspot in recent years. However, existing studies have mostly relied on the assumption that the LKA characteristic aligned with the driver's preference is consistent with this driver's naturalistic driving characteristic. Nevertheless, this assumption may not always hold true, causing limitations to the effectiveness of this method. This paper proposes a novel method for a Driver-Adaptive Lane-Keeping Assistance (DALKA) system based on drivers' real preferences. First, metrics are extracted from collected naturalistic driving data using action point theory to describe drivers' naturalistic driving characteristics. Then, the subjective and objective evaluation method is introduced to obtain the real preference of each test driver for the LKA system. Finally, machine learning methods are employed to train a model that relates naturalistic driving characteristics to the drivers' real preferences, and the model-predicted preferences are integrated into the DALKA system. The developed DALKA system is then subjectively evaluated by the drivers. The results show that our DALKA system, developed using this method, can enhance or maintain the subjective evaluations of the LKA system for most drivers.

Controlled Switching of the Number of Skyrmions in a Magnetic Nanodot by Electric Fields.

Magnetic skyrmions are topological swirling spin configurations that hold promise for building future magnetic memories and logic circuits. Skyrmionic devices typically rely on the electrical manipulation of a single skyrmion, but controllably manipulating a group of skyrmions can lead to more compact and memory-efficient devices. Here, an electric-field-driven cascading transition of skyrmion clusters in a nanostructured ferromagnetic/ferroelectric multiferroic heterostructure is reported, which allows a continuous multilevel transition of the number of skyrmions in a one-by-one manner. Most notably, the transition is non-volatile and reversible, which is crucial for multi-bit memory applications. Combined experiments and theoretical simulations reveal that the switching of skyrmion clusters is induced by the strain-mediated modification of both the interfacial Dzyaloshinskii-Moriya interaction and effective uniaxial anisotropy. The results not only open up a new direction for constructing low-power-consuming, non-volatile, and multi-bit skyrmionic devices, but also offer valuable insights into the fundamental physics underlying the voltage manipulation of skyrmion clusters.

The toxicity study on marine low-temperature lysozyme.

Marine low-temperature lysozyme is purified from a marine bacterium. The lysozyme can keep high activity at low-temperature and has broad-spectrum antibiotic reaction. This study was undertaken to investigate the major characteristics, acute and subchronic toxicity of marine low-temperature lysozyme. The relative molecular weight of this lysozyme was determined as approximate 16 kD; its optimum pH value and temperature towards Micrococcus lysodleikticus were pH 6.5 and 35 degrees C, respectively. The lysozyme activity was slightly enhanced by Zn(2+) and Cu(2+) and slightly inhibited by Mn(2+) and Ag(+). The lysozyme showed good compatibility to many common chemical agents such as EDTA (0.1%), KH(2)PO(4) (1.0%), etc. In experiments on acute toxicity, the drug was injected through the tail vein of mice, and intoxication symptoms and date of death were recorded. The 50% lethal dose (LD(50)) of Marine low-temperature lysozyme and 95%, 99% confidence interval (CI) was calculated. The subchronic study was designed to determine whether effects progressed with repeated Marine low-temperature lysozyme exposure. Wistar rats were tested by daily intragastric administration of Marine low-temperature lysozyme at the doses of 1.0; 0.5; 0.25 g/kg bw for 90 days. The LD(50) value of lysozyme was 4530 mg/kg bw; 90 days of Marine low-temperature lysozyme treatment at three doses, and there is no significant difference on blood biochemistry and organ index in drug treatment groups compared to saline treatment group. There is no affirmative pathologic change of all the observed organs in this study. The present results suggest that Marine low-temperature lysozyme can be safely used at the dose of experiment applied.