56 research outputs found
Optimizing Associative Information Transfer within Content-addressable Memory
Original article can be found at: http://www.oldcitypublishing.com/IJUC/IJUC.htmlPeer reviewe
A Process-Oriented Architecture for Complex System Modelling
A fine-grained massively-parallel process-oriented model of platelets (potentially artificial) within a blood vessel is presented. This is a CSP inspired design, expressed and implemented using the occam-pi language. It is part of the TUNA pilot study on nanite assemblers at the universities of York, Surrey and Kent. The aim for this model is to engineer emergent behaviour from the platelets, such that they respond to a wound in the blood vessel wall in a way similar to that found in the human body -- i.e. the formation of clots to stem blood flow from the wound and facilitate healing. An architecture for a three dimensional model (relying strongly on the dynamic and mobile capabilities of occam-pi) is given, along with mechanisms for visualisation and interaction. The biological accuracy of the current model is very approximate. However, its process-oriented nature enables simple refinement (through the addition of processes modelling different stimulants/inhibitors of the clotting reaction, different platelet types and other participating organelles) to greater and greater realism. Even with the current system, simple experiments are possible and have scientific interest (e.g. the effect of platelet density on the success of the clotting mechanism in stemming blood flow: too high or too low and the process fails). General principles for the design of large and complex system models are drawn. The described case study runs to millions of processes engaged in ever-changing communication topologies. It is free from deadlock, livelock, race hazards and starvation em by design, employing a small set of synchronisation patterns for which we have proven safety theorems
"Going back to our roots": second generation biocomputing
Researchers in the field of biocomputing have, for many years, successfully
"harvested and exploited" the natural world for inspiration in developing
systems that are robust, adaptable and capable of generating novel and even
"creative" solutions to human-defined problems. However, in this position paper
we argue that the time has now come for a reassessment of how we exploit
biology to generate new computational systems. Previous solutions (the "first
generation" of biocomputing techniques), whilst reasonably effective, are crude
analogues of actual biological systems. We believe that a new, inherently
inter-disciplinary approach is needed for the development of the emerging
"second generation" of bio-inspired methods. This new modus operandi will
require much closer interaction between the engineering and life sciences
communities, as well as a bidirectional flow of concepts, applications and
expertise. We support our argument by examining, in this new light, three
existing areas of biocomputing (genetic programming, artificial immune systems
and evolvable hardware), as well as an emerging area (natural genetic
engineering) which may provide useful pointers as to the way forward.Comment: Submitted to the International Journal of Unconventional Computin
El mundo de las ciencias de la complejidad
La situación es verdaderamente apasionante. Mientras que en el mundo
llamado real –y entonces se hace referencia a dominios como la política, la
economía, los conflictos militares y sociales, por ejemplo–, la percepción
natural –digamos: de los medios y la opinión pública– es que el país y el
mundo se encuentran en condiciones difíciles; en algunos casos, dramática;
y en muchas ocasiones trágica, en el campo del progreso del conocimiento
asistimos a una magnífica vitalidad. Esta vitalidad se expresa en la ciencia de
punta y, notablemente, en las ciencias de la complejidad.
Mientras que la ciencia normal –para volver a la expresión de Kuhn– se
encuentra literalmente a la defensiva en numerosos campos, temas y problemas
–digamos, a la defensiva con respecto al decurso de los acontecimientos
y a las dinámicas del mundo contemporáneo–, en el contexto del estudio de
los sistemas complejos adaptativos asistimos a una vitalidad que es prácticamente
desconocida para la corriente principal de académicos –independientemente
de los niveles en los que trabajan–, de científicos, de administradores
de educación y de ciencia y tecnología (por ejemplo rectores, vicerrectores,
decanos, directores de departamentos, tomadores de decisión, políticos y gobernantes).
La corriente principal del conocimiento (mainstream) desconoce
una circunstancia, un proceso, una dinámica que sí es conocida por parte de
quienes trabajan e investigan activamente en el campo de las ciencias de la
complejidad
Diverse Exploration via InfoMax Options
In this paper, we study the problem of autonomously discovering temporally
abstracted actions, or options, for exploration in reinforcement learning. For
learning diverse options suitable for exploration, we introduce the infomax
termination objective defined as the mutual information between options and
their corresponding state transitions. We derive a scalable optimization scheme
for maximizing this objective via the termination condition of options,
yielding the InfoMax Option Critic (IMOC) algorithm. Through illustrative
experiments, we empirically show that IMOC learns diverse options and utilizes
them for exploration. Moreover, we show that IMOC scales well to continuous
control tasks.Comment: Preprint. Under revie
Development and Evaluation of Sensor Concepts for Ageless Aerospace Vehicles: Report 6 - Development and Demonstration of a Self-Organizing Diagnostic System for Structural Health Monitoring
This report describes a significant advance in the capability of the CSIRO/NASA structural health monitoring Concept Demonstrator (CD). The main thrust of the work has been the development of a mobile robotic agent, and the hardware and software modifications and developments required to enable the demonstrator to operate as a single, self-organizing, multi-agent system. This single-robot system is seen as the forerunner of a system in which larger numbers of small robots perform inspection and repair tasks cooperatively, by self-organization. While the goal of demonstrating self-organized damage diagnosis was not fully achieved in the time available, much of the work required for the final element that enables the robot to point the video camera and transmit an image has been completed. A demonstration video of the CD and robotic systems operating will be made and forwarded to NASA
ELDEN: Exploration via Local Dependencies
Tasks with large state space and sparse rewards present a longstanding
challenge to reinforcement learning. In these tasks, an agent needs to explore
the state space efficiently until it finds a reward. To deal with this problem,
the community has proposed to augment the reward function with intrinsic
reward, a bonus signal that encourages the agent to visit interesting states.
In this work, we propose a new way of defining interesting states for
environments with factored state spaces and complex chained dependencies, where
an agent's actions may change the value of one entity that, in order, may
affect the value of another entity. Our insight is that, in these environments,
interesting states for exploration are states where the agent is uncertain
whether (as opposed to how) entities such as the agent or objects have some
influence on each other. We present ELDEN, Exploration via Local DepENdencies,
a novel intrinsic reward that encourages the discovery of new interactions
between entities. ELDEN utilizes a novel scheme -- the partial derivative of
the learned dynamics to model the local dependencies between entities
accurately and computationally efficiently. The uncertainty of the predicted
dependencies is then used as an intrinsic reward to encourage exploration
toward new interactions. We evaluate the performance of ELDEN on four different
domains with complex dependencies, ranging from 2D grid worlds to 3D robotic
tasks. In all domains, ELDEN correctly identifies local dependencies and learns
successful policies, significantly outperforming previous state-of-the-art
exploration methods.Comment: Accepted to NeurIPS 202
OnCreate and the virtual teammate: an analysis of online creative processes and remote collaboration
This paper explores research undertaken by a consortium of 10 universities from across Europe as part of an EU Erasmus Strategic Partnership project called OnCreate. Recent research and experiences prove the importance of the design and implementation of online courses that are learner-centred, include collaboration and integrate rich use of media in authentic environments. The OnCreate project explores the specific challenges of creative processes in such environments. The first research phase comprises a comparative qualitative analysis of collaboration practices in design-related study programmes at the ten participating universities. A key outcome of this research was in identifying the shortcomings of the hierarchical role models of established Learning Management Systems (such as Moodle or Blackboard) and the tendency towards evolving 'mash-up' environments to support creative online collaboration
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