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The practical driving cycle is of great significance in studying the control strategy of vehicles, and effective clustering of micro-trips is the key to obtaining the typical driving cycle. A novel and efficient method for constructing typical driving cycles is presented in this paper. First, by combining the preying behavior and random behavior of the artificial fish swarm algorithm (AFSA) with particle swarm optimization (PSO), a modified particle swarm optimization (MPSO) is proposed. By comparing the means and standard deviations of the optima, MPSO is verified as much more accurate and stable than PSO, AFSA, select particle swarm optimization (SPSO) and cross particle swarm optimization (CPSO) in the optimization calculation of four typical multi-modal benchmark functions. Second, by applying MPSO to optimize the k-means algorithm, the k-MPSO clustering algorithm is obtained. In the case of clustering the Iris standard data set, the average error rates of the k-means algorithm and k-MPSO clustering algorithm are 11.6% and 7.8%, respectively, which means that the k-MPSO clustering algorithm has a stronger searching ability. Finally, with the ECAN Tools software, real-world driving data that include thousands of micro-trips in Jinan are collected, and 19 representative characteristic parameters are selected to fully describe the driving conditions. After principal component analysis (PCA), the k-MPSO clustering algorithm method is applied to cluster the micro-trips into three classes and construct the typical driving cycle in Jinan.

Silvered polyimide films, synthesized by an in-situ self-assembly method, find many applications in the fields of electronics and aerospace materials. In this work, polyimide/siloxanes were introduced into silvered PI films by an in-situ self-assembly process, which were resistant to atomic oxygen. Their atomic oxygen (AO) resistance behaviors were studied, wherein the mass loss of 20% Si-poly(amide acid salt) PAAS film was 30 ug cm−2 after exposure to AO fluence of 1.33 × 1020 O (10.5 h) and 190 ug cm−2 even after 42 h. Additionally, the volume resistivity value of the flexible PI/Ag composite film was 9.9 Ω cm−1 after 260 cycles of bending. The peel strength of PI/Ag/PI composite film was seven times more than that of the coated one (0.7 N cm-1 to 0.1 N cm-1). Moreover, (Dynamic Mechanical Analysis) DMA and (Thermogravimetric Analysis) TGA data also show that the introduction of self-encapsulating PAAS can not only increase the interlayer strength but maintain the performance of PI film. X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy were also employed to test the relative AO resistance behaviors. Thus, the silvered poly(siloxane amic acid) Si-PI composite films have AO resistance, high peel strength and alternating conductivity/ insulative effect, and hence can serve as a flexible printed circuit board for potential applications in low earth orbit.

This paper introduces the UML modeling, and then gives the basic steps of UML for software process modeling with regarding sales management of the modeling process as an example and then using UML visual modeling to approach realization process.