1D Printing of Recyclable Robots

Recent advances in 3D printing are revolutionizing manufacturing, enabling the fabrication of structures with unprecedented complexity and functionality. Yet biological systems are able to fabricate systems with far greater complexity using a process that involves assembling and folding a linear string. Here, we demonstrate a 1D printing system that uses an approach inspired by the ribosome to fabricate a variety of specialized robotic automata from a single string of source material. This proof-of-concept system involves both a novel manufacturing platform that configures the source material using folding and a computational optimization tool that allows designs to be produced from the specification of high-level goals. We show that our 1D printing system is able to produce three distinct robots from the same source material, each of which is capable of accomplishing a specialized locomotion task. Moreover, we demonstrate the ability of the printer to use recycled material to produce new designs, enabling an autonomous manufacturing ecosystem capable of repurposing previous iterations to accomplish new tasks.

 

Title: 1D Printing of  Recyclable Robots
Authors: Daniel Cellucci, Robert MacCurdy, Hod Lipson, Sebastian Risi (2017)
In: EEE Robotics and Automation Letters (RA-L).
Link: http://ieeexplore.ieee.org/document/7950924/
PDF: http://sebastianrisi.com/wp-content/uploads/cellucci_ral17.pdf
Video: https://youtu.be/ElW0O2IiuXA

Source: ieeexplore.ieee.org

Limited individual attention and online virality of low-quality information

Social media are massive marketplaces where ideas and news compete for our attention. Previous studies have shown that quality is not a necessary condition for online virality and that knowledge about peer choices can distort the relationship between quality and popularity. However, these results do not explain the viral spread of low-quality information, such as the digital misinformation that threatens our democracy. We investigate quality discrimination in a stylized model of an online social network, where individual agents prefer quality information, but have behavioural limitations in managing a heavy flow of information. We measure the relationship between the quality of an idea and its likelihood of becoming prevalent at the system level. We find that both information overload and limited attention contribute to a degradation of the market’s discriminative power. A good tradeoff between discriminative power and diversity of information is possible according to the model. However, calibration with empirical data characterizing information load and finite attention in real social media reveals a weak correlation between quality and popularity of information. In these realistic conditions, the model predicts that low-quality information is just as likely to go viral, providing an interpretation for the high volume of misinformation we observe online.

 

Limited individual attention and online virality of low-quality information
Xiaoyan Qiu, Diego F. M. Oliveira, Alireza Sahami Shirazi, Alessandro Flammini & Filippo Menczer

Nature Human Behaviour 1, Article number: 0132 (2017)
doi:10.1038/s41562-017-0132

Source: www.nature.com

Efficient Integration in Multi-Community Networks

We study structures for efficient integration of multi-community networks where building bridges across communities incur an additional link cost compared to links within a community. Building on the connections models with direct link cost and direct and indirect benefits, we show that the efficient structure for homogeneous cost and benefit parameters, and for communities of arbitrary size, always has a diameter no greater than 3. We further show that if the internal cost is not small enough to justify a full graph for each community, integration always follows one of these two structures: Either a single star, or a new structure we introduce in this paper, called parallel-hyperstar, which is a special multi-core/periphery structure with parallel links among core nodes of different communities. We offer cost and benefit conditions where each structure is efficient and discuss the stability conditions of those structures.

Source: papers.ssrn.com

Entropy 2018: From Physics to Information Sciences and Geometry

One of the most frequently used scientific words, is the word “Entropy”. The reason is that it is related to two main scientific domains: physics and information theory. Its origin goes back to the start of physics (thermodynamics), but since Shannon, it has become related to information theory. This conference is an opportunity to bring researchers of these two communities together and create a synergy. The main topics and sessions of the conference cover:

  • Physics: classical Thermodynamics and Quantum
  • Statistical physics and Bayesian computation
  • Geometrical science of information, topology and metrics
  • Maximum entropy principle and inference
  • Kullback and Bayes or information theory and Bayesian inference
  • Entropy in action (applications)

The inter-disciplinary nature of contributions from both theoretical and applied perspectives are very welcome, including papers addressing conceptual and methodological developments, as well as new applications of entropy and information theory.

 

Entropy 2018: From Physics to Information Sciences and Geometry

  14-16 May 2018
Auditorium Enric Casassas, Faculty of Chemistry, University of Barcelona, Barcelona, Spain

Source: sciforum.net

The Evolution of Beauty: How Darwin’s Forgotten Theory of Mate Choice Shapes the Animal World – and Us

A major reimagining of how evolutionary forces work, revealing how mating preferences—what Darwin termed “the taste for the beautiful”—create the extraordinary range of ornament in the animal world.

In the great halls of science, dogma holds that Darwin’s theory of natural selection explains every branch on the tree of life: which species thrive, which wither away to extinction, and what features each evolves. But can adaptation by natural selection really account for everything we see in nature?
     Yale University ornithologist Richard Prum—reviving Darwin’s own views—thinks not. Deep in tropical jungles around the world are birds with a dizzying array of appearances and mating displays: Club-winged Manakins who sing with their wings, Great Argus Pheasants who dazzle prospective mates with a four-foot-wide cone of feathers covered in golden 3D spheres, Red-capped Manakins who moonwalk. In thirty years of fieldwork, Prum has seen numerous display traits that seem disconnected from, if not outright contrary to, selection for individual survival. To explain this, he dusts off Darwin’s long-neglected theory of sexual selection in which the act of choosing a mate for purely aesthetic reasons—for the mere pleasure of it—is an independent engine of evolutionary change.
    Mate choice can drive ornamental traits from the constraints of adaptive evolution, allowing them to grow ever more elaborate. It also sets the stakes for sexual conflict, in which the sexual autonomy of the female evolves in response to male sexual control. Most crucially, this framework provides important insights into the evolution of human sexuality, particularly the ways in which female preferences have changed male bodies, and even maleness itself, through evolutionary time.
     The Evolution of Beauty presents a unique scientific vision for how nature’s splendor contributes to a more complete understanding of evolution and of ourselves.

Source: www.amazon.com