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The micro-Doppler signature is a time-varying frequency modulation imparted on radar echo caused by target's micro-motion. To save the trouble of constructing template in the target classification, this paper investigates the micro-Doppler signature of wheeled and tracked vehicles and proposes a template-free classification method. Firstly, the echo signature is established and the micro-Doppler difference of these two kinds of targets is analysed. Secondly, some new micro-Doppler features are defined according to their difference. The new defined features are micro-Doppler bandwidth, micro-Doppler expansion rate and micro-Doppler peak number. According to the characteristic of the micro-Doppler in the time-frequency domain, we proposed to realise the feature extraction by Hough transformation. Lastly, template-free subjection functions are proposed to define the relationship between the features and the vehicles. By fuzzy comprehensive evaluation, the final classification result is obtained by combining the subjection probabilities together. Experimental results based on the simulated data and measured data are presented, which prove that the algorithm has good performance.

Based on the rank-dependent expected utility model (Quiggin, 1991), hypotheses are formed in this study regarding optimal prize promotion structure with reference to associated probabilistic aspects. Referencing both modeling works and related behavioral theories, we compared several
design schemes. Using purchase scenarios of a low-value product (bread) and a high-value product (cell phone) we determined the optimal design among promotion schemes that differ by winning probability, prize amount, and number of prize value levels. We found that a promotion offering a combination
of high-value prizes plus some low-value prizes was invariably preferred over a promotion offering only high- or low-value prizes. We also explored whether these high- or low-value prizes should be in a series of ascending value or prizes at each value level should be of the same value and
whether or not some moderately valuable prizes should also be included.