2,766 research outputs found
Meta-heuristic algorithms in car engine design: a literature survey
Meta-heuristic algorithms are often inspired by natural phenomena, including the evolution of species in Darwinian natural selection theory, ant behaviors in biology, flock behaviors of some birds, and annealing in metallurgy. Due to their great potential in solving difficult optimization problems, meta-heuristic algorithms have found their way into automobile engine design. There are different optimization problems arising in different areas of car engine management including calibration, control system, fault diagnosis, and modeling. In this paper we review the state-of-the-art applications of different meta-heuristic algorithms in engine management systems. The review covers a wide range of research, including the application of meta-heuristic algorithms in engine calibration, optimizing engine control systems, engine fault diagnosis, and optimizing different parts of engines and modeling. The meta-heuristic algorithms reviewed in this paper include evolutionary algorithms, evolution strategy, evolutionary programming, genetic programming, differential evolution, estimation of distribution algorithm, ant colony optimization, particle swarm optimization, memetic algorithms, and artificial immune system
JPEG steganography with particle swarm optimization accelerated by AVX
Digital steganography aims at hiding secret messages in digital data transmitted over insecure channels. The JPEG format is prevalent in digital communication, and images are often used as cover objects in digital steganography. Optimization methods can improve the properties of images with embedded secret but introduce additional computational complexity to their processing. AVX instructions available in modern CPUs are, in this work, used to accelerate data parallel operations that are part of image steganography with advanced optimizations.Web of Science328art. no. e544
An Effective Power Dispatch of Photovoltaic Generators in DC Networks via the Antlion Optimizer
This paper studies the problem regarding the optimal power dispatch of photovoltaic (PV) distributed generators (DGs) in Direct Current (DC) grid-connected and standalone networks. The mathematical model employed considers the reduction of operating costs, energy losses, and CO2 emissions as objective functions, and it integrates all technical and operating constraints implied by DC grids in a scenario of variable PV generation and power demand. As a solution methodology, a master–slave strategy was proposed, whose master stage employs Antlion Optimizer (ALO) for identifying the values of power to be dispatched by each PV-DG installed in the grid, whereas the slave stage uses a matrix hourly power flow method based on successive approximations to evaluate the objective functions and constraints associated with each solution proposed within the iterative process of the ALO. Two test scenarios were considered: a grid-connected network that considers the operating characteristics of the city of Medellín, Antioquia, and a standalone network that uses data from the municipality of Capurganá, Chocó, both of them located in Colombia. As comparison methods, five continuous optimization methods were used which were proposed in the specialized literature to solve optimal power flow problems in DC grids: the crow search algorithm, the particle swarm optimization algorithm, the multiverse optimization algorithm, the salp swarm algorithm, and the vortex search algorithm. The effectiveness of the proposed method was evaluated in terms of the solution, its repeatability, and its processing times, and it obtained the best results with respect to the comparison methods for both grid types. The simulation results obtained for both test systems evidenced that the proposed methodology obtained the best results with regard to the solution, with short processing times for all of the objective functions analyzed
A Novel Path Planning Optimization Algorithm for Semi-Autonomous UAV in Bird Repellent Systems Based in Particle Swarm Optimization
Bird damage to fruit crops causes significant monetary losses to farmers annually. The
application of traditional bird repelling methods such as bird cannons and tree netting
became inefficient in the long run, keeping high maintenance and reduced mobility. Due to
their versatility, Unmanned Aerial Vehicles (UAVs) can be beneficial to solve this problem.
However, due to their low battery capacity that equals low flight duration, it is necessary to
evolve path planning optimization.
A path planning optimization algorithm of UAVs based on Particle Swarm Optimization
(PSO) is presented in this dissertation. This technique was used due to the need for an easy
implementation optimization algorithm to start the initial tests. The PSO algorithm is
simple and has few control parameters while maintaining a good performance. This path
planning optimization algorithm aims to manage the drone's distance and flight time,
applying optimization and randomness techniques to overcome the disadvantages of the
traditional systems. The proposed algorithm's performance was tested in three study cases:
two of them in simulation to test the variation of each parameter and one in the field to test
the influence on battery management and height influence. All cases were tested in the three
possible situations: same incidence rate, different rates, and different rates with no bird
damage to fruit crops.
The proposed algorithm presents promising results with an outstanding reduced average
error in the total distance for the path planning obtained and low execution time. However,
it is necessary to point out that the path planning optimization algorithm may have difficulty
finding a suitable solution if there is a bad ratio between the total distance for path planning
and points of interest. The field tests were also essential to understand the algorithm's
behavior of the path planning algorithm in the UAV, showing that there is less energy
discharged with fewer points of interest, but that do not correlates with the flight time. Also,
there is no association between the maximum horizontal speed and the flight time, which
means that the function to calculate the total distance for path planning needs to be
adjusted.Anualmente, os danos causados pelas aves em pomares criam perdas monetárias
significativas aos agricultores. A aplicação de métodos tradicionais de dispersão de aves,
como canhões repelentes de aves e redes nas árvores, torna-se ineficiente a longo prazo,
sendo ainda de alta manutenção e de mobilidade reduzida. Devido à sua versatilidade, os
Veículos Aéreos Não Tripulados (VANT) podem ser benéficos para resolver este problema.
No entanto, devido à baixa capacidade das suas baterias, que se traduz num baixo tempo de
voo, é necessário otimizar o planeamento dos caminhos.
Nesta dissertação, é apresentado um algoritmo de otimização para planeamento de
caminhos para VANT baseado no Particle Swarm Optimization (PSO). Para se iniciarem os
primeiros testes do algoritmo proposto, a técnica utilizada foi a supracitada devido à
necessidade de um algoritmo de otimização fácil de implementar. O algoritmo PSO é
simples e possuí poucos parâmetros de controlo, mantendo um bom desempenho. Este
algoritmo de otimização de planeamento de caminhos propõe-se a gerir a distância e o
tempo de voo do drone, aplicando técnicas de otimização e de aleatoriedade para superar a
sua desvantagem relativamente aos sistemas tradicionais. O desempenho do algoritmo de
planeamento de caminhos foi testado em três casos de estudo: dois deles em simulação para
testar a variação de cada parâmetro e outro em campo para testar a capacidade da bateria.
Todos os casos foram testados nas três situações possíveis: mesma taxa de incidência, taxas
diferentes e taxas diferentes sem danos de aves.
Os resultados apresentados pelo algoritmo proposto demonstram um erro médio muto
reduzido na distância total para o planeamento de caminhos obtido e baixo tempo de
execução. Porém, é necessário destacar que o algoritmo pode ter dificuldade em encontrar
uma solução adequada se houver uma má relação entre a distância total para o planeamento
de caminhos e os pontos de interesse. Os testes de campo também foram essenciais para
entender o comportamento do algoritmo na prática, mostrando que há menos energia
consumida com menos pontos de interesse, sendo que este parâmetro não se correlaciona
com o tempo de voo. Além disso, não há associação entre a velocidade horizontal máxima e
o tempo da missão, o que significa que a função de cálculo da distância total para o
planeamento de caminhos requer ser ajustada
Novel metaheuristic hybrid spiral-dynamic bacteria-chemotaxis algorithms for global optimisation
© 2014 Elsevier B.V. All rights reserved. This paper presents hybrid spiral-dynamic bacteria-chemotaxis algorithms for global optimisation and their application to control of a flexible manipulator system. Spiral dynamic algorithm (SDA) has faster convergence speed and good exploitation strategy. However, the incorporation of constant radius and angular displacement in its spiral model causes the exploration strategy to be less effective hence resulting in low accurate solution. Bacteria chemotaxis on the other hand, is the most prominent strategy in bacterial foraging algorithm. However, the incorporation of a constant step-size for the bacteria movement affects the algorithm performance. Defining a large step-size results in faster convergence speed but produces low accuracy while de.ning a small step-size gives high accuracy but produces slower convergence speed. The hybrid algorithms proposed in this paper synergise SDA and bacteria chemotaxis and thus introduce more effective exploration strategy leading to higher accuracy, faster convergence speed and low computation time. The proposed algorithms are tested with several benchmark functions and statistically analysed via nonparametric Friedman and Wilcoxon signed rank tests as well as parametric t-test in comparison to their predecessor algorithms. Moreover, they are used to optimise hybrid Proportional-Derivative-like fuzzy-logic controller for position tracking of a flexible manipulator system. The results show that the proposed algorithms significantly improve both convergence speed as well as fitness accuracy and result in better system response in controlling the flexible manipulator
A Comprehensive Survey on Particle Swarm Optimization Algorithm and Its Applications
Particle swarm optimization (PSO) is a heuristic global optimization method, proposed originally by Kennedy and Eberhart in 1995. It is now one of the most commonly used optimization techniques. This survey presented a comprehensive investigation of PSO. On one hand, we provided advances with PSO, including its modifications (including quantum-behaved PSO, bare-bones PSO, chaotic PSO, and fuzzy PSO), population topology (as fully connected, von Neumann, ring, star, random, etc.), hybridization (with genetic algorithm, simulated annealing, Tabu search, artificial immune system, ant colony algorithm, artificial bee colony, differential evolution, harmonic search, and biogeography-based optimization), extensions (to multiobjective, constrained, discrete, and binary optimization), theoretical analysis (parameter selection and tuning, and convergence analysis), and parallel implementation (in multicore, multiprocessor, GPU, and cloud computing forms). On the other hand, we offered a survey on applications of PSO to the following eight fields: electrical and electronic engineering, automation control systems, communication theory, operations research, mechanical engineering, fuel and energy, medicine, chemistry, and biology. It is hoped that this survey would be beneficial for the researchers studying PSO algorithms
Parallel bio-inspired methods for model optimization and pattern recognition
Nature based computational models are usually inherently parallel. The collaborative intelligence in those models emerges from the simultaneous instruction processing by simple independent units (neurons, ants, swarm members, etc...). This dissertation investigates the benefits of such parallel models in terms of efficiency and accuracy. First, the viability of a parallel implementation of bio-inspired metaheuristics for function optimization on consumer-level graphic cards is studied in detail. Then, in an effort to expose those parallel methods to the research community, the metaheuristic implementations were abstracted and grouped in an open source parameter/function optimization library libCudaOptimize. The library was verified against a well known benchmark for mathematical function minimization, and showed significant gains in both execution time and minimization accuracy. Crossing more into the application side, a parallel model of the human neocortex was developed. This model is able to detect, classify, and predict patterns in time-series data in an unsupervised way. Finally, libCudaOptimize was used to find the best parameters for this neocortex model, adapting it to gesture recognition within publicly available datasets
Agent-based modelling and Swarm Intelligence in systems engineering
El objetivo de la tesis doctoral es evaluar la utilidad de las técnicas Modelado Basado en Agentes, algoritmos de optimización Swarm Intelligence y programación paralela sobre tarjeta gráfica en el campo de la Ingeniería de Sistemas y Automática.
Se ha realizado un revisión bibliográfica y desarrollado un marco de desarrollo de la técnica de Modelado Basado en Agentes. Esta técnica se ha empleado para realizar un modelo de un reactor de fangos activados (que se engloba dentro del proceso de depuración de aguas residuales).
Se ha desarrollado una notación complementaria para la descripción de modelos basados en agentes desde el punto de vista de la ingeniería de sistemas.
Se ha presentado asimismo un algoritmo de optimización basado en agentes bajo la filosofía Swarm Intelligence.
Se han trabajado con las técnicas de paralelización sobre tarjeta gráfica para reducir los tiempos de simulación de modelos y algoritmos.
Se trata por lo tanto de un tesis de integración de varias tecnologías.Departamento de Ingeniería de Sistemas y Automátic
AI Applications to Power Systems
Today, the flow of electricity is bidirectional, and not all electricity is centrally produced in large power plants. With the growing emergence of prosumers and microgrids, the amount of electricity produced by sources other than large, traditional power plants is ever-increasing. These alternative sources include photovoltaic (PV), wind turbine (WT), geothermal, and biomass renewable generation plants. Some renewable energy resources (solar PV and wind turbine generation) are highly dependent on natural processes and parameters (wind speed, wind direction, temperature, solar irradiation, humidity, etc.). Thus, the outputs are so stochastic in nature. New data-science-inspired real-time solutions are needed in order to co-develop digital twins of large intermittent renewable plants whose services can be globally delivered
- …