12,251 research outputs found
Computational paradigm for dynamic logic-gates in neuronal activity
In 1943 McCulloch and Pitts suggested that the brain is composed of reliable
logic-gates similar to the logic at the core of today's computers. This
framework had a limited impact on neuroscience, since neurons exhibit far
richer dynamics. Here we propose a new experimentally corroborated paradigm in
which the truth tables of the brain's logic-gates are time dependent, i.e.
dynamic logicgates (DLGs). The truth tables of the DLGs depend on the history
of their activity and the stimulation frequencies of their input neurons. Our
experimental results are based on a procedure where conditioned stimulations
were enforced on circuits of neurons embedded within a large-scale network of
cortical cells in-vitro. We demonstrate that the underlying biological
mechanism is the unavoidable increase of neuronal response latencies to ongoing
stimulations, which imposes a nonuniform gradual stretching of network delays.
The limited experimental results are confirmed and extended by simulations and
theoretical arguments based on identical neurons with a fixed increase of the
neuronal response latency per evoked spike. We anticipate our results to lead
to better understanding of the suitability of this computational paradigm to
account for the brain's functionalities and will require the development of new
systematic mathematical methods beyond the methods developed for traditional
Boolean algebra.Comment: 32 pages, 14 figures, 1 tabl
A Sound and Complete Axiomatization of Majority-n Logic
Manipulating logic functions via majority operators recently drew the
attention of researchers in computer science. For example, circuit optimization
based on majority operators enables superior results as compared to traditional
logic systems. Also, the Boolean satisfiability problem finds new solving
approaches when described in terms of majority decisions. To support computer
logic applications based on majority a sound and complete set of axioms is
required. Most of the recent advances in majority logic deal only with ternary
majority (MAJ- 3) operators because the axiomatization with solely MAJ-3 and
complementation operators is well understood. However, it is of interest
extending such axiomatization to n-ary majority operators (MAJ-n) from both the
theoretical and practical perspective. In this work, we address this issue by
introducing a sound and complete axiomatization of MAJ-n logic. Our
axiomatization naturally includes existing majority logic systems. Based on
this general set of axioms, computer applications can now fully exploit the
expressive power of majority logic.Comment: Accepted by the IEEE Transactions on Computer
Design Automation and Design Space Exploration for Quantum Computers
A major hurdle to the deployment of quantum linear systems algorithms and
recent quantum simulation algorithms lies in the difficulty to find inexpensive
reversible circuits for arithmetic using existing hand coded methods. Motivated
by recent advances in reversible logic synthesis, we synthesize arithmetic
circuits using classical design automation flows and tools. The combination of
classical and reversible logic synthesis enables the automatic design of large
components in reversible logic starting from well-known hardware description
languages such as Verilog. As a prototype example for our approach we
automatically generate high quality networks for the reciprocal , which is
necessary for quantum linear systems algorithms.Comment: 6 pages, 1 figure, in 2017 Design, Automation & Test in Europe
Conference & Exhibition, DATE 2017, Lausanne, Switzerland, March 27-31, 201
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,
-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
Mathematical Estimation of Logical Masking Capability of Majority/Minority Gates Used in Nanoelectronic Circuits
In nanoelectronic circuit synthesis, the majority gate and the inverter form
the basic combinational logic primitives. This paper deduces the mathematical
formulae to estimate the logical masking capability of majority gates, which
are used extensively in nanoelectronic digital circuit synthesis. The
mathematical formulae derived to evaluate the logical masking capability of
majority gates holds well for minority gates, and a comparison with the logical
masking capability of conventional gates such as NOT, AND/NAND, OR/NOR, and
XOR/XNOR is provided. It is inferred from this research work that the logical
masking capability of majority/minority gates is similar to that of XOR/XNOR
gates, and with an increase of fan-in the logical masking capability of
majority/minority gates also increases
Synthesis and Optimization of Reversible Circuits - A Survey
Reversible logic circuits have been historically motivated by theoretical
research in low-power electronics as well as practical improvement of
bit-manipulation transforms in cryptography and computer graphics. Recently,
reversible circuits have attracted interest as components of quantum
algorithms, as well as in photonic and nano-computing technologies where some
switching devices offer no signal gain. Research in generating reversible logic
distinguishes between circuit synthesis, post-synthesis optimization, and
technology mapping. In this survey, we review algorithmic paradigms ---
search-based, cycle-based, transformation-based, and BDD-based --- as well as
specific algorithms for reversible synthesis, both exact and heuristic. We
conclude the survey by outlining key open challenges in synthesis of reversible
and quantum logic, as well as most common misconceptions.Comment: 34 pages, 15 figures, 2 table
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