A novel mobile self-reconfigurable robot is presented. This robot consists of several independent units. Each unit is composed of modular components including ultrasonic sensor, camera, communication, computation, and...A novel mobile self-reconfigurable robot is presented. This robot consists of several independent units. Each unit is composed of modular components including ultrasonic sensor, camera, communication, computation, and mobility parts, and is capable of simple self-reconfiguring to enhance its mobility by expanding itself. Several units can not only link into a train or other shapes autonomously via camera and sensors to be a united whole robot for obstacle clearing, but also disjoin to be separate units under control after missions. To achieve small overall size, compact mechanical structures are adopted in modular components design, and a miniature advanced RISC machines （ARM） based embedded controller is developed for minimal power consumption and efficient global control. The docking experiment between two units has also been implemented.展开更多
Aims Plant-pollinator interaction networks are dynamic entities,and seasonal variation in plant phenology can reshape their structure on both short and long timescales.However,such seasonal dynamics are rarely conside...Aims Plant-pollinator interaction networks are dynamic entities,and seasonal variation in plant phenology can reshape their structure on both short and long timescales.However,such seasonal dynamics are rarely considered,especially for oceanic island pollination networks.Here,we assess changes in the temporal dynamics of plant-pollinator interactions in response to seasonal variation in floral resource richness in oceanic island communities.Methods We evaluated seasonal variations of pollination networks in the Yongxing Island community.Four temporal qualitative pollination networks were analyzed using plant-pollinator interaction data of the four seasons.We collected data on plant-pollinator interactions during two consecutive months in each of the four seasons.Four network-level indices were calculated to characterize the overall structure of the networks.Statistical analyses of community dissimilarity were used to compare this community across four seasons to explore the underlying factors driving these patterns.We also evaluated the temporal variation in two species-level indices of plant and pollinator functional groups.Important Findings Both network-level specialization and modularity showed a significantly opposite trend compared with plant species richness across four seasons.Increased numbers of plant species might promote greater competition among pollinators,leading to increased niche overlap and causing decreased specialization and modularity and vice versa.Further analyses suggested that the season-to-season turnover of interactions was dominated by interaction rewiring.Thus,the seasonal changes in niche overlap among pollinators lead to interaction rewiring,which drives interaction turnover in this community.Hawkmoths had higher values of specialization and Apidae had higher values of species strength compared with other pollinator functional groups.These findings should be considered when exploring plant-pollinator interactions in ecosystems of isolated oceanic islands and in other ecosystems.展开更多
基金Supported by the National High Technology Research and Development Programme of China ( No. 2004AA420110)Heilongjiang Province Technology Foundation (No. GB04A502)
文摘A novel mobile self-reconfigurable robot is presented. This robot consists of several independent units. Each unit is composed of modular components including ultrasonic sensor, camera, communication, computation, and mobility parts, and is capable of simple self-reconfiguring to enhance its mobility by expanding itself. Several units can not only link into a train or other shapes autonomously via camera and sensors to be a united whole robot for obstacle clearing, but also disjoin to be separate units under control after missions. To achieve small overall size, compact mechanical structures are adopted in modular components design, and a miniature advanced RISC machines （ARM） based embedded controller is developed for minimal power consumption and efficient global control. The docking experiment between two units has also been implemented.
基金supported by the National Natural Science Foundation of China(grant no.31800447)the Chinese Academy of Sciences(grant no.XDA13020504)+1 种基金the Natural Science Foundation of Guangdong Province(grant no.2018A030310385)the National Natural Science Foundation of China(grant no.U1701246).
文摘Aims Plant-pollinator interaction networks are dynamic entities,and seasonal variation in plant phenology can reshape their structure on both short and long timescales.However,such seasonal dynamics are rarely considered,especially for oceanic island pollination networks.Here,we assess changes in the temporal dynamics of plant-pollinator interactions in response to seasonal variation in floral resource richness in oceanic island communities.Methods We evaluated seasonal variations of pollination networks in the Yongxing Island community.Four temporal qualitative pollination networks were analyzed using plant-pollinator interaction data of the four seasons.We collected data on plant-pollinator interactions during two consecutive months in each of the four seasons.Four network-level indices were calculated to characterize the overall structure of the networks.Statistical analyses of community dissimilarity were used to compare this community across four seasons to explore the underlying factors driving these patterns.We also evaluated the temporal variation in two species-level indices of plant and pollinator functional groups.Important Findings Both network-level specialization and modularity showed a significantly opposite trend compared with plant species richness across four seasons.Increased numbers of plant species might promote greater competition among pollinators,leading to increased niche overlap and causing decreased specialization and modularity and vice versa.Further analyses suggested that the season-to-season turnover of interactions was dominated by interaction rewiring.Thus,the seasonal changes in niche overlap among pollinators lead to interaction rewiring,which drives interaction turnover in this community.Hawkmoths had higher values of specialization and Apidae had higher values of species strength compared with other pollinator functional groups.These findings should be considered when exploring plant-pollinator interactions in ecosystems of isolated oceanic islands and in other ecosystems.
