*****  To join INSNA, visit  *****

Looking forward to seeing some/many of you at the ASAs in Philly next 
Meanwhile, enjoy Lord Simcoe Day, Ontario's finest hoiday!

   Barry Wellman

   Step by step, link by link, putting it together--Streisand/Sondheim
        The earth to be spannd, connected by network--Walt Whitman
              It's Always Something--Roseanne Roseannadanna
   NetLab Network      			                            FRSC
   Distinguished Visiting Scholar   Social Media Lab   Ryerson University
         Founder, International Network for Social Network Analysis
   NETWORKED: The New Social Operating System  Lee Rainie & Barry Wellman  

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Date: Mon, 6 Aug 2018 11:04:25 +0000
From: "[utf-8] Complexity Digest" <[log in to unmask]>
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Subject: [utf-8] Latest Complexity Digest Posts

Learn about the latest and greatest related to complex systems research. More at

Optimized flocking of autonomous drones in confined environments

We address a fundamental issue of collective motion of aerial robots: how to ensure that large flocks of autonomous drones seamlessly navigate in confined spaces. The numerous existing flocking models are rarely tested on actual hardware because they typically neglect some crucial aspects of multirobot systems. Constrained motion and communication capabilities, delays, perturbations, or the presence of barriers should be modeled and treated explicitly because they have large effects on collective behavior during the cooperation of real agents. Handling these issues properly results in additional model complexity and a natural increase in the number of tunable parameters, which calls for appropriate optimization methods to be coupled tightly to model development. In this paper, we propose such a flocking model for real drones incorporating an evolutionary optimization framework with carefully chosen order parameters and fitness functions. We numerically demonstrated that the
induced swarm behavior remained stable under realistic conditions for large flock sizes and notably for large velocities. We showed that coherent and realistic collective motion patterns persisted even around perturbing obstacles. Furthermore, we validated our model on real hardware, carrying out field experiments with a self-organized swarm of 30 drones. This is the largest of such aerial outdoor systems without central control reported to date exhibiting flocking with collective collision and object avoidance. The results confirmed the adequacy of our approach. Successfully controlling dozens of quadcopters will enable substantially more efficient task management in various contexts involving drones.

Optimized flocking of autonomous drones in confined environments
Gábor Vásárhelyi, Csaba Virágh, Gerg˙˙ Somorjai, Tamás Nepusz, Agoston E. Eiben and Tamás Vicsek
Science Robotics  18 Jul 2018:
Vol. 3, Issue 20, eaat3536
DOI: 10.1126/scirobotics.aat3536

Source: (

Evidence for a conserved quantity in human mobility

Recent seminal works on human mobility have shown that individuals constantly exploit a small set of repeatedly visited locations1,2,3. A concurrent study has emphasized the explorative nature of human behaviour, showing that the number of visited places grows steadily over time4,5,6,7. How to reconcile these seemingly contradicting facts remains an open question. Here, we analyse high-resolution multi-year traces of ~40,000 individuals from 4 datasets and show that this tension vanishes when the long-term evolution of mobility patterns is considered. We reveal that mobility patterns evolve significantly yet smoothly, and that the number of familiar locations an individual visits at any point is a conserved quantity with a typical size of ~25. We use this finding to improve state-of-the-art modelling of human mobility4,8. Furthermore, shifting the attention from aggregated quantities to individual behaviour, we show that the size of an individual˙˙s set of preferred locations
correlates with their number of social interactions. This result suggests a connection between the conserved quantity we identify, which as we show cannot be understood purely on the basis of time constraints, and the ˙˙Dunbar number˙˙9,10 describing a cognitive upper limit to an individual˙˙s number of social relations. We anticipate that our work will spark further research linking the study of human mobility and the cognitive and behavioural sciences.

Evidence for a conserved quantity in human mobility
Laura Alessandretti, Piotr Sapiezynski, Vedran Sekara, Sune Lehmann & Andrea Baronchelli
Nature Human Behaviour volume 2, pages 485˙˙491 (2018)

Source: (

Does putting your emotions into words make you feel better? Measuring the minute-scale dynamics of emotions from online data

    Studies of affect labeling, i.e. putting your feelings into words, indicate that it can attenuate positive and negative emotions. Here we track the evolution of individual emotions for tens of thousands of Twitter users by analyzing the emotional content of their tweets before and after they explicitly report having a strong emotion. Our results reveal how emotions and their expression evolve at the temporal resolution of one minute. While the expression of positive emotions is preceded by a short but steep increase in positive valence and followed by short decay to normal levels, negative emotions build up more slowly, followed by a sharp reversal to previous levels, matching earlier findings of the attenuating effects of affect labeling. We estimate that positive and negative emotions last approximately 1.25 and 1.5 hours from onset to evanescence. A separate analysis for male and female subjects is suggestive of possible gender-specific differences in emotional dynamics.

Does putting your emotions into words make you feel better? Measuring the minute-scale dynamics of emotions from online data

Rui Fan, Ali Varamesh, Onur Varol, Alexander Barron, Ingrid van de Leemput, Marten Scheffer, Johan Bollen

Source: (

Boolean Networks and Their Applications in Science and Engineering, Special Issue in Complexity

In the last decades, Boolean networks (BNs) have emerged as an effective mathematical tool to model not only computational processes, but also several phenomena from science and engineering. For this reason, the development of the theory of such models has become a compelling need that has attracted the interest of many research groups in applied mathematics in recent years. Dynamics of BNs are traditionally associated with complexity, since they are composed of many identical elemental units whose behavior is relatively simple in comparison with the behavior of the entire system.

Submission Deadline Friday, 28 December 2018

Publication Date May 2019

Source: (

Complexcity@POLITO ˙˙ Turin, Italy, October 29-30 2018

    The workshop is the 13th of a series of tutorial workshops annually organized to explore the emergence of new research fields in which modeling, analysis and control of nonlinear and complex systems play a role of growing importance. These workshops have been traditionally devoted to an interdisciplinary audience with particular attention to PhD students and young researchers. The theme of this year is ˙˙Complexity and The City˙˙ with a unique focus on interactions, mobility, epidemics, information and misinformation spreading, and many other complex phenomena occurring in urban environments.

The workshop will gather scholars, students, and practitioners for two days of presentations and debates around complex systems science and its interplay with urban environments. A series of plenary lectures from renowned scholars is planned, while PhD students and young researchers will have dedicated sessions to present their research activity in an effective and appealing way. Social events will foster interaction and creation of collaboration opportunities.

Source: (

Sponsored by the Complex Systems Society.
Founding Editor: Gottfried Mayer.
Editor-in-Chief: Carlos Gershenson.

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