6,080 research outputs found
An Adaptive Genetic Algorithm with Dynamic Population Size for Optimizing Join Queries
The problem of finding the optimal join ordering executing a query to a relational database
management system is a combinatorial optimization problem, which makes deterministic exhaustive solution
search unacceptable for queries with a great number of joined relations. In this work an adaptive genetic
algorithm with dynamic population size is proposed for optimizing large join queries. The performance of the
algorithm is compared with that of several classical non-deterministic optimization algorithms. Experiments have
been performed optimizing several random queries against a randomly generated data dictionary. The proposed
adaptive genetic algorithm with probabilistic selection operator outperforms in a number of test runs the canonical
genetic algorithm with Elitist selection as well as two common random search strategies and proves to be a viable
alternative to existing non-deterministic optimization approaches
Computational intelligence techniques for maximum energy efficiency of cogeneration processes based on internal combustion engines
153 p.El objeto de la tesis consiste en desarrollar estrategias de modelado y optimización del rendimiento energético de plantas de cogeneración basadas en motores de combustión interna (MCI), mediante el uso de las últimas tecnologías de inteligencia computacional. Con esta finalidad se cuenta con datos reales de una planta de cogeneración de energía, propiedad de la compañía EnergyWorks, situada en la localidad de Monzón (provincia de Huesca). La tesis se realiza en el marco de trabajo conjunto del Grupo de Diseño en Electrónica Digital (GDED) de la Universidad del País Vasco UPV/EHU y la empresa Optimitive S.L., empresa dedicada al software avanzado para la mejora en tiempo real de procesos industriale
Distributed classifier based on genetically engineered bacterial cell cultures
We describe a conceptual design of a distributed classifier formed by a
population of genetically engineered microbial cells. The central idea is to
create a complex classifier from a population of weak or simple classifiers. We
create a master population of cells with randomized synthetic biosensor
circuits that have a broad range of sensitivities towards chemical signals of
interest that form the input vectors subject to classification. The randomized
sensitivities are achieved by constructing a library of synthetic gene circuits
with randomized control sequences (e.g. ribosome-binding sites) in the front
element. The training procedure consists in re-shaping of the master population
in such a way that it collectively responds to the "positive" patterns of input
signals by producing above-threshold output (e.g. fluorescent signal), and
below-threshold output in case of the "negative" patterns. The population
re-shaping is achieved by presenting sequential examples and pruning the
population using either graded selection/counterselection or by
fluorescence-activated cell sorting (FACS). We demonstrate the feasibility of
experimental implementation of such system computationally using a realistic
model of the synthetic sensing gene circuits.Comment: 31 pages, 9 figure
Biological Organisms as Semiosic Systems: the importance of strong and weak anticipation
The biological realm is examined as a semiosic system that transforms basic matter into a complex and intimately networked diversity of morphological forms according to generic sets of self‐generated rules of formation. Semiosis is understood to operate as a function f(x)=y where the mediative rules of formation, f, operate within predictive or anticipatory capacities. Strong and weak anticipation are examined and the paper concludes that strong anticipation, operating as a virtual or imaginary hypothesis construction is a basic property of the biological realm. Strong anticipation enables the biological species to develop multiple hypothetical ‘network motifs’ about its future activities within the environment. The species will ‘choose’ one of these probabilities – any of which would be functional – to articulate in actual time and space. This theory rejects random mutation as the source of innovative evolution and adaptation. Weak anticipation is defined as Natural Selection and is described as a post hoc model of strong anticipation’s ‘selected solution’
Simulation Intelligence: Towards a New Generation of Scientific Methods
The original "Seven Motifs" set forth a roadmap of essential methods for the
field of scientific computing, where a motif is an algorithmic method that
captures a pattern of computation and data movement. We present the "Nine
Motifs of Simulation Intelligence", a roadmap for the development and
integration of the essential algorithms necessary for a merger of scientific
computing, scientific simulation, and artificial intelligence. We call this
merger simulation intelligence (SI), for short. We argue the motifs of
simulation intelligence are interconnected and interdependent, much like the
components within the layers of an operating system. Using this metaphor, we
explore the nature of each layer of the simulation intelligence operating
system stack (SI-stack) and the motifs therein: (1) Multi-physics and
multi-scale modeling; (2) Surrogate modeling and emulation; (3)
Simulation-based inference; (4) Causal modeling and inference; (5) Agent-based
modeling; (6) Probabilistic programming; (7) Differentiable programming; (8)
Open-ended optimization; (9) Machine programming. We believe coordinated
efforts between motifs offers immense opportunity to accelerate scientific
discovery, from solving inverse problems in synthetic biology and climate
science, to directing nuclear energy experiments and predicting emergent
behavior in socioeconomic settings. We elaborate on each layer of the SI-stack,
detailing the state-of-art methods, presenting examples to highlight challenges
and opportunities, and advocating for specific ways to advance the motifs and
the synergies from their combinations. Advancing and integrating these
technologies can enable a robust and efficient hypothesis-simulation-analysis
type of scientific method, which we introduce with several use-cases for
human-machine teaming and automated science
Evolutionary strategies in swarm robotics controllers
Nowadays, Unmanned Vehicles (UV) are widespread around the world. Most of these
vehicles require a great level of human control, and mission success is reliant on this
dependency. Therefore, it is important to use machine learning techniques that will train the
robotic controllers to automate the control, making the process more efficient.
Evolutionary strategies may be the key to having robust and adaptive learning in robotic
systems. Many studies involving UV systems and evolutionary strategies have been
conducted in the last years, however, there are still research gaps that need to be addressed,
such as the reality gap. The reality gap occurs when controllers trained in simulated
environments fail to be transferred to real robots.
This work proposes an approach for solving robotic tasks using realistic simulation and
using evolutionary strategies to train controllers. The chosen setup is easily scalable for multirobot
systems or swarm robots.
In this thesis, the simulation architecture and setup are presented, including the drone
simulation model and software. The drone model chosen for the simulations is available in the
real world and widely used, such as the software and flight control unit. This relevant factor
makes the transition to reality smoother and easier. Controllers using behavior trees were
evolved using a developed evolutionary algorithm, and several experiments were conducted.
Results demonstrated that it is possible to evolve a robotic controller in realistic
simulation environments, using a simulated drone model that exists in the real world, and also
the same flight control unit and operating system that is generally used in real world
experiments.Atualmente os Veículos Não Tripulados (VNT) encontram-se difundidos por todo o Mundo.
A maioria destes veículos requerem um elevado controlo humano, e o sucesso das missões
está diretamente dependente deste fator. Assim, é importante utilizar técnicas de
aprendizagem automática que irão treinar os controladores dos VNT, de modo a automatizar o
controlo, tornando o processo mais eficiente.
As estratégias evolutivas podem ser a chave para uma aprendizagem robusta e adaptativa
em sistemas robóticos. Vários estudos têm sido realizados nos últimos anos, contudo, existem
lacunas que precisam de ser abordadas, tais como o reality gap. Este facto ocorre quando os
controladores treinados em ambientes simulados falham ao serem transferidos para VNT
reais.
Este trabalho propõe uma abordagem para a resolução de missões com VNT, utilizando
um simulador realista e estratégias evolutivas para treinar controladores. A arquitetura
escolhida é facilmente escalável para sistemas com múltiplos VNT.
Nesta tese, é apresentada a arquitetura e configuração do ambiente de simulação,
incluindo o modelo e software de simulação do VNT. O modelo de VNT escolhido para as
simulações é um modelo real e amplamente utilizado, assim como o software e a unidade de
controlo de voo. Este fator é relevante e torna a transição para a realidade mais suave. É
desenvolvido um algoritmo evolucionário para treinar um controlador, que utiliza behavior
trees, e realizados diversos testes.
Os resultados demonstram que é possível evoluir um controlador em ambientes de
simulação realistas, utilizando um VNT simulado mas real, assim como utilizando as mesmas
unidades de controlo de voo e software que são amplamente utilizados em ambiente real
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