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ABSTRACT With the widespread worldwide adoption of location‐based service technologies, accurate and reliable driving trajectories have become crucial. However, because of the inherent deficiencies of sensor devices, accurate road matching results may not always be obtained directly from trajectory data, which poses a challenge for many location and trajectory based services. Existing map‐matching techniques mainly focus on high‐sampling‐rate trajectory data while paying relatively less attention to low‐frequency trajectory data. Low‐sampling‐rate trajectory data have greater matching difficulties than high‐sampling‐rate data owing to the limited available information. Moreover, in the case of signal loss or interference, the accuracy of map‐matching algorithms can decrease significantly for low‐sampling‐rate data. To achieve accurate map‐matching results for low‐sampling‐rate trajectory data, this study proposes a map‐matching algorithm based on probability interpolation. First, the trajectory data are denoised to eliminate redundant trajectory points. Second, the concept of the probability truth value is introduced to handle the relationship between the interpolated virtual points and actual sampled trajectory points accurately. A higher probability truth value indicates a higher confidence level of the interpolation. Third, the denoised trajectory data are interpolated and a probability truth value is assigned based on the interpolation accuracy. Finally, a comprehensive probability composed of the probability truth value, emission probability, and transition probability is used to determine the correctly matched road segments. Experimental results on real trajectory datasets demonstrated that the proposed algorithm outperformed several advanced algorithms in terms of accuracy and performance. [ABSTRACT FROM AUTHOR]

Bursaphelenchus xylophilus is a pest that interferes with the health of forests and hinders the development of the forestry industry, and its spread is influenced by changes in abiotic factors and human activities. The potential distribution areas of B. xylophilus in China under four shared-economic pathways were predicted using the optimized MaxEnt model (version 3.4.3), combining data from a variety of environmental variables: (1) prediction of natural environmental variables predicted under current climate models; (2) prediction of natural environmental variables + human activities under current climate models; and (3) prediction of natural environmental variables under the future climate models (2050s and 2070s). Meanwhile, whether the niche of B. xylophilus has changed over time is analyzed. The results showed that human activities, precipitation in the driest month, annual precipitation, and elevation had significant effects on the distribution of B. xylophilus. In the current conditions, human activities greatly reduced the survival area of B. xylophilus, and its suitable distribution area was mainly concentrated in the southwestern and central regions of China. Under the influence of climate change in the future, the habitat of B. xylophilus will gradually spread to the northeast. In addition, the ecological niche overlap analysis showed that B. xylophilus in future climate was greater than 0.74. This study provides important information for understanding the ecological adaptation and potential risk of B. xylophilus, which can help guide the decision making of pest control and forest protection. [ABSTRACT FROM AUTHOR]

Repeated programmability has emerged as a desired property in smart device engineering, but the programmability will fatigue upon repeated applications due to the unmatched mechanical property between the layer materials and the polymeric glue that is required to integrate the two individual oriented layers. It is reported here that glue‐free antifatigue programmable laminate materials can be made with films resulted from solid‐phase molecular self‐assembly (SPMSA). The SPMSA films are created by squeezing the precipitates of oppositely charged polyelectrolytes and DTAB with a noodle machine, where the hydrophobic DTAB molecules self‐assembled into wormlike micelles and oriented along the squeezing direction. The surface molecules in this film are endowed with sufficient mobility in the presence of hydration water, so that two such films are able to be pressed into a laminate material owing to the hydrophobic and electrostatic interactions between the molecules on the two adjacent surfaces. As the water evaporated gradually, the left laminate materials are glue‐free with the same composition. When many of such films are integrated with specific designs, complicated shape programming is able to be achieved, and the programmability is reversible without fatigue. The current strategy is envisioned as a potent intriguing pathway leading to advanced programable materials. [ABSTRACT FROM AUTHOR]