Burst pulses for positive corona discharges in atmospheric air:the collective movement of charged species

Positive corona burst pulses are an unstable pulse mode.They appear in a small range of the onset stage,and their current pulses result from the collective movement of charged species.This paper focused on the connections between these pulses and the collective movement of charged species.The movement of species is divided into four parts with respect to time:the(1)initial growth of species,(2)formation and development of the streamer region and negative ion sheath,(3)dead time(the time interval between the pulses),and(4)rapid re-growth of species.The movement of the species in the four parts and the correspondence with the current pulse were analyzed.The numerical results indicated the following:the rapid rising of the species matched the rising edge of the pulses,the streamer region,and negative ion sheath appeared in the falling edge of the primary pulse,and the rapid re-growth of species matched the re-ignition of the pulses.The results were in qualitative agreement with deductions and experimental observations in the literature.

Collective Movement Simulation:Methods and Applications

Collective movement simulations are challenging and important in many areas,including life science,mathematics,physics,information science and public safety.In this survey,we provide a comprehensive review of the state-of-the-art techniques for collective movement simulations.We start with a discussion on certain concepts to help beginners understand it more systematically.Then,we analyze the intelligence among different collective objects and the emphasis in different fields.Next,we classify existing collective movement simulation methods into four categories according to their effects,namely versatility,accuracy,dynamic adaptability,and assessment feedback capability.Furthermore,we introduce five applications of layout optimization,emergency control,dispatching,unmanned systems,and other derivative applications.Finally,we summarize possible future research directions.

Infant attraction:why social bridging matters for female leadership in Tibetan macaques

Leadership is a key issue in the study of collective behavior in social animals.Affiliation-leadership models predict that dyadic partner preferences based on grooming relationships or allianee formation positively affect an in dividua I's decision to follow or support a con spec ific.In the case of many primate species,females without young infants are attracted to mother-infant dyads.However,the effects of mother-infant-female associations on affiliation-leadership models remain less clear.In free-rangi ng Tibeta n macaques Macaca thibetana,we used social network analysis to examine the importance of mother-inf a nt-adult female"social bridging eve nts as a predictor of who leads and who follows during group movement.Social bridging is a common behavior in Tibetan macaques and occurs whe n 2 adults,gen erally females,engage in coordinated in fa nt handling.Using eigenvector centrality coefficients of social bridging as a measure of social affiliation,we found that among lactating females,initiating bridging behavior with another female played a sign讦icant role in leadership success,with the assisting female following the mother during group movement.Among non lactati ng females,this was not the case.Our results in dicate that in fa nt attracti on can be a strong trigger in collective action and directing group movement in Tibetan macaques and provides benefits to mothers who require helpers and social support in order to ensure the safety of their infants.Our study provides new insights into the importance of the third-party effect in rethinking affiliation-leadership models in group-living animals.