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Begonia ferox C.I Peng & Yan Liu (2013) was rated as endangered according to Red List of Chinese Plants. In this study, we report the complete chloroplast genome of B. ferox. The chloroplast genome is 169,114 bp in length as the circular, with the GC content of 35.5%, composed by a large single-copy (LSC) region of 75,887 bp, a small single-copy (SSC) region of 18,105 bp, and two inverted repeat regions (IRs) of 37,561 bp in each. The genome comprises 174 encoded genes in total, including 114 protein-coding genes, eight ribosomal RNA genes, and 52 transfer RNA genes. Phylogenetic analysis indicated that B. ferox is genetically closest to B. gulongshanensis.

This paper attempts to disclose the features of the mixed traffic flow of manually driven vehicles (MVs) and autonomous vehicles (AVs). Considering dynamic headway, the mixed traffic flow was modelled based on the improved single-land cellular automata (CA) traffic flow model (DHD) proposed by Zhang Ningxi. The established CA model was adopted to obtain the maximum flow of the mixed traffic flow and was analyzed under different proportions of AVs. On this basis, the features of the mixed traffic flow were summarized. The main results are as follows: the proportion of AVs has a significant impact on the mixed traffic flow; when the proportion reached 0.6, the flow of the whole lane was twice that of the MV traffic flow. At a low density, the AV proportion has an obvious influence on mixed traffic flow. At a high density, the mixed traffic flow changed very little, as the AV proportion increased from 0 to 5. The reason is that the flow of the whole lane is constrained by the fact that MVs cannot move faster. However, when the AV proportion reached 0.8, the flow of the whole lane became three times that at the proportion of 0.6. At the speed of 126 km/h, the flow rate was 2.5 times the speed limit of 54 km/h. The findings lay a theoretical basis for the modelling of multilane mixed traffic flow.

The genetic diversity and structure of 4 wild population and 2 ex situ conserved population of Hopea chinensis (Merr.) Hand.-Mazz were analyzed and compared by ISSR marker method. Fifty eight bands were amplified from total genomic DNA with 10 primers in which there were 51 polymorphic, the percentage of polymorphic bands of populations ranged from 53.45 to 79.31, with an average value of 69.82, indicating the presence of high genetic diversity. However, the percentage of polymorphic band, Nei’s diversity index (He) and Shannon information index (I) of wild populations (86.21, 0.3636 and 0.5232, respectively) were higher than those of ex situ conservated populations (77.59, 0.3153 and 0.4597, respectively), which meant that ex situ conservations of Hopea chinensis had a narrow genetic diversity. Population structure analysis revealed that genetic variation of Hopea chinensis was 0.0373, so the genetic differentiation was 3.73% among populations, and 96.27% in populations. Furthermore, the strong gene flow (Nm = 12.8896) would be the main reason of limited population differentiation. It concluded that ex situ population had not yet fully covered the entire genetic diversity of Hopea chinensis.

Traffic simulation models have been extensively used because of their ability to model the dynamic stochastic nature of transportation systems. Parameter calibration is very complex and does not give optimal results easily. Besides, it is also time-consuming especially for large and complex networks. Initially, the procedure of traffic micro-simulation parameter calibration was put forward. A Vehicle Intelligent Simulation Software Model (VISSIM) models were selected for parameter calibration in complex-network, and, the role of Simultaneous Perturbation Genetic Algorithm (SPGA) was examined in the optimization of component. Moreover an automatic calibration methodology for micro-simulation models was developed in order to select the best parameter set based on the observed Intelligent Transportation Systems (ITS) data which proved effective for different networks. Finally, the methodology was applied to calibrate the Beijing city VISSIM models, followed by the comparison of convergence rate of Genetic Algorithm (GA), Simultaneous Perturbation Stochastic Approximation (SPSA) and SPGA algorithm. The results show that the SPGA was effective and had good performance.

Through the research of hydraulic transmission unit in HMCVT, the mathematical model of hydraulic transmission and braking energy recovery unit is established. Based on AMESIM simulation software, the simulation model was established. According the actual situation, and set the related parameters. The working process of the braking energy recovery system is simulated and the influence of the speed mode of the engine input transmission on the performance of the braking energy recovery system is studied. The simulation results show that the speed mode of the engine input transmission has no obvious effect on the braking performance, but has a great influence on the braking energy recovery efficiency of the system. This study provides a basis for the development of braking energy recovery control strategy.

The features of startup process and the reasons which result in the failure of small-scale flat-plate type capillary pumped loop (CPL) evaporator during the preheating stage are analyzed. The unsteady heat transfer model of evaporator in the fully-flooded startup stage is presented, and the model is solved with SIMPLE algorithm. The numerical results show the preheating stage of evaporator requires less time. The average temperature difference between upper surface and bottom surface of wick has a steady maximum value corresponding to different applied heat loads. For the higher heat flux, the preheating stage requires shorter time, and average temperature difference is bigger, it is useful for successful startup of capillary evaporator.