Computers from plants we never made. Speculations

We discuss possible designs and prototypes of computing systems that could be based on morphological development of roots, interaction of roots, and analog electrical computation with plants, and plant-derived electronic components. In morphological plant processors data are represented by initial configuration of roots and configurations of sources of attractants and repellents; results of computation are represented by topology of the roots' network. Computation is implemented by the roots following gradients of attractants and repellents, as well as interacting with each other. Problems solvable by plant roots, in principle, include shortest-path, minimum spanning tree, Voronoi diagram, $\alpha$-shapes, convex subdivision of concave polygons. Electrical properties of plants can be modified by loading the plants with functional nanoparticles or coating parts of plants of conductive polymers. Thus, we are in position to make living variable resistors, capacitors, operational amplifiers, multipliers, potentiometers and fixed-function generators. The electrically modified plants can implement summation, integration with respect to time, inversion, multiplication, exponentiation, logarithm, division. Mathematical and engineering problems to be solved can be represented in plant root networks of resistive or reaction elements. Developments in plant-based computing architectures will trigger emergence of a unique community of biologists, electronic engineering and computer scientists working together to produce living electronic devices which future green computers will be made of.Comment: The chapter will be published in "Inspired by Nature. Computing inspired by physics, chemistry and biology. Essays presented to Julian Miller on the occasion of his 60th birthday", Editors: Susan Stepney and Andrew Adamatzky (Springer, 2017

Learning in complex public systems:The case of MINUSMA’s intelligence organization

Public systems are facing increasingly complex challenges such as poverty and terrorism. In this paper, we seek to demonstrate the theoretical as well as practical value of complexity science, by investigating how key characteristics of a Complex Adaptive System (CAS) work out in practice within the intelligence organization of the ongoing nation-building mission in Mali (MINUSMA). Our main finding is that the learning properties of the CAS suffer when its structural properties are not sufficiently developed. In MINUSMA, major improvements can especially be made in (re)developing the minimum specs—in which strategic and operational demands, ideally, converge

Single- and dual-carrier microwave noise abatement in the deep space network

The NASA/JPL Deep Space Network (DSN) microwave ground antenna systems are presented which simultaneously uplink very high power S-band signals while receiving very low level S- and X-band downlinks. Tertiary mechanisms associated with elements give rise to self-interference in the forms of broadband noise burst and coherent intermodulation products. A long-term program to reduce or eliminate both forms of interference is described in detail. Two DSN antennas were subjected to extensive interference testing and practical cleanup program; the initial performance, modification details, and final performance achieved at several planned stages are discussed. Test equipment and field procedures found useful in locating interference sources are discussed. Practices deemed necessary for interference-free operations in the DSN are described. Much of the specific information given is expected to be easily generalized for application in a variety of similar installations. Recommendations for future investigations and individual element design are given

Observations on Human Performance in Air Traffic Control Operations: Preliminaries to a Cognitive Model

We have previously described a computational approach to modeling human performance, built using the Apex architecture [1],in which extended behavioral sequences are automatically constructed from simpler CPMGOMS templates [2]. Here we report on efforts to extend that method to the more complex domain of air traffic control operations. We describe the overall approach and our initial analysis of patterns of human performance observed in a simulation of air traffic control operations conducted by the Federal Aviation Administration. Of particular interest are patterns that characterize how operators manage multiple tasks, and distribute their attention over items. We show how templates in our compositional approach might be structured to accommodate these patterns