In order to solve the problem the existing vertical handoff algorithms of vehicle heterogeneous wireless network do not consider the diversification of network's status, an optimized vertical handoff algorithm based on markov process is proposed and discussed in this paper. This algorithm takes into account that the status transformation of available network will affect the quality of service (QoS) of vehicle terminal's communication service. Firstly, Markov process is used to predict the transformation of wireless network's status after the decision via transition probability. Then the weights of evaluating parameters will be determined by fuzzy logic method. Finally, by comparing the total incomes of each wireless network, including handoff decision incomes, handoff execution incomes and communication service incomes after handoff, the optimal network to handoff will be selected. Simulation results show that: the algorithm proposed, compared to the existing algorithm, is able to receive a higher level of load balancing and effectively improves the average blocking rate, packet loss rate and ping-pang effect.
Federated filter was an important method to estimate high-precision navigation parameters based on "SINS/GPS/CNS". A no-feedback federated filter with UD_UKF algorithm was designed in the paper, a threetime amendment scheme to correct navigation parameters was designed at the same time and the mathematical model of SINS/GPS/CNS was established in launch inertial coordinate system too. The paper discussed the simulation conditions and a lot of simulations were carried out to compare 2 aspects: (1)the performance between four navigation mode, which respectively is SINS, SINS/GPS, SINS/CNS, SINS/GPS/CNS;(2)the estimate precision of federated filter and that of centralized Kalman filter. The results of simulation showed that the designed federated filter and amendment scheme based on SINS/GPS/CNS had high estimate precision and led to gain high hitting precision of ballistic missile, that is to say position errors were less than 20 meter and velocity errors were less than 0.1m/s in simulation.
Lichens are important components of macrofungi, and thus they are also main subjects in the Red List Assessment of Macrofungi in China. A total of 2,164 lichen species were evaluated here, including 2,145 ascomycete lichen species and 19 basidiomycete lichen species. These species were organized into 2 phyla, 9 classes, 34 orders, 92 families and 352 genera. The results showed that, of the 28 species identified as threatened, 3 species were Critically Endangered (CR), 7 species were Endangered (EN) and 18 species were Vulnerable (VU). These 28 represented 1.29% of all evaluated species, with 6 other species considered to be Near Threatened (NT) and 657 species assessed as Least Concern (LC). More than half the species, 1,473 (68.07%), were Data Deficient (DD) and could not be further evaluated due to lack of data. This highlights the severe lack of lichen research and the urgent need for lichen taxonomists in China. The extremely slow growth, weak adaptability to habitat degradation, particular sensitivity to air pollution, narrow distribution and small population size characteristic of lichens all contribute to the susceptible state of lichens that face habitat destruction caused by human activities. In addition, it is worth noting that some lichen species evaluated as Vulnerable here, have since been overexploited due to their edibility and well-known medicinal value. These species' conservation status will be further aggravated if they continue to lack effective protection.
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