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11.
Hazard perception tests may not be transferable between different countries, due to differences in traffic culture and infrastructure. Therefore, different instruments might be necessary for assessing hazard perception in various countries. The aim of the current study was to develop the Lithuanian hazard perception test based on static traffic images and test its psychometric properties. Thirty-four experienced drivers participated in a pilot study, and 125 drivers with diverse driving experience took part in the main study. The final test contained 27 static traffic scenes and the participants were asked to respond if they saw a hazard or not. Results demonstrated that the test has satisfactory internal consistency and test-retest reliability. It differentiated between inexperienced and experienced drivers, and between those experienced drivers who had less than three or more than three crashes in their driving history. The test has sufficient psychometric properties for research; still further development is needed in order to apply it for individual testing and decisions about licence provision. 相似文献
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An iterative transmit power allocation (PA) algorithm was proposed for group-wise space-time block coding (G-STBC) systems with group-wise successive interference cancellation (GSIC) receivers. Group-wise interference suppression (GIS) filters are employed to separate each group's transmit signals from other interferences and noise. While the total power on all transmit symbols is constrained, all transmit PA coefficients are updated jointly according to the channel information at each iteration. Through PA, each detection symbol has the same post-detection signal to interference-and-noise ratio (SINR). The simulation results verify that the proposed PA algorithm converges at the equilibrium quickly after few iterations, and it achieves much lower bit error rates than the previous single symbol SIC PA and the fixed ratio PA algorithms for G-STBC systems with GSIC receivers . 相似文献
13.
分析了射频功率放大器的非线性特性,对常见的功率放火器线性化技术的原理和实现方法进行了系统的分析,比较了它们的优缺点,为选择射频功率放大器的线性化技术提供了重要的参考。 相似文献
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OD矩阵与PA矩阵辨析 总被引:1,自引:0,他引:1
OD矩阵与PA矩阵是交通规划时用来说明交通小区之间出行量而定义的两个相似的概念.从他们各自的含义出发,探讨二者之间的联系和区别,说明各自的作用及相互之间的转化,有助于分清他们之间的本质。 相似文献
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