Multipopulation-based multi-level parallel enhanced Jaya algorithms

To solve optimization problems, in the field of engineering optimization, an optimal value of a specific function must be found, in a limited time, within a constrained or unconstrained domain. Metaheuristic methods are useful for a wide range of scientific and engineering applications, which accelerate being able to achieve optimal or near-optimal solutions. The metaheuristic method called Jaya has generated growing interest because of its simplicity and efficiency. We present Jaya-based parallel algorithms to efficiently exploit cluster computing platforms (heterogeneous memory platforms). We propose a multi-level parallel algorithm, in which, to exploit distributed-memory architectures (or multiprocessors), the outermost layer of the Jaya algorithm is parallelized. Moreover, in internal layers, we exploit shared-memory architectures (or multicores) by adding two more levels of parallelization. This two-level internal parallel algorithm is based on both a multipopulation structure and an improved heuristic search path relative to the search path of the sequential algorithm. The multi-level parallel algorithm obtains average efficiency values of 84% using up to 120 and 135 processes, and slightly accelerates the convergence with respect to the sequential Jaya algorithm.This research was supported by the Spanish Ministry of Economy and Competitiveness under Grant TIN2015-66972-C5-4-R and Grant TIN2017-89266-R, co-financed by FEDER funds (MINECO/FEDER/UE)

A comprehensive survey on cultural algorithms

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Enhanced Parallel Sine Cosine Algorithm for Constrained and Unconstrained Optimization

The sine cosine algorithm’s main idea is the sine and cosine-based vacillation outwards or towards the best solution. The first main contribution of this paper proposes an enhanced version of the SCA algorithm called as ESCA algorithm. The supremacy of the proposed algorithm over a set of state-of-the-art algorithms in terms of solution accuracy and convergence speed will be demonstrated by experimental tests. When these algorithms are transferred to the business sector, they must meet time requirements dependent on the industrial process. If these temporal requirements are not met, an efficient solution is to speed them up by designing parallel algorithms. The second major contribution of this work is the design of several parallel algorithms for efficiently exploiting current multicore processor architectures. First, one-level synchronous and asynchronous parallel ESCA algorithms are designed. They have two favors; retain the proposed algorithm’s behavior and provide excellent parallel performance by combining coarse-grained parallelism with fine-grained parallelism. Moreover, the parallel scalability of the proposed algorithms is further improved by employing a two-level parallel strategy. Indeed, the experimental results suggest that the one-level parallel ESCA algorithms reduce the computing time, on average, by 87.4% and 90.8%, respectively, using 12 physical processing cores. The two-level parallel algorithms provide extra reductions of the computing time by 91.4%, 93.1%, and 94.5% with 16, 20, and 24 processing cores, including physical and logical cores. Comparison analysis is carried out on 30 unconstrained benchmark functions and three challenging engineering design problems. The experimental outcomes show that the proposed ESCA algorithm behaves outstandingly well in terms of exploration and exploitation behaviors, local optima avoidance, and convergence speed toward the optimum. The overall performance of the proposed algorithm is statistically validated using three non-parametric statistical tests, namely Friedman, Friedman aligned, and Quade tests.This research was supported by the Spanish Ministry of Science, Innovation and Universities and the Research State Agency under Grant RTI2018-098156-B-C54 cofinanced by FEDER funds and the Ministry of Science and Innovation and the Research State Agency under Grant PID2020-120213RB-I00 cofinanced by FEDER funds

Structural optimization of self-supported dome roof frames under gust wind loads

PhD ThesisDome roofs are large structures often subject to variable wind, snow and other loading conditions, in addition to their own weight. A wide variety of structural designs are used in practice, and finding the optimal arrangement of trusses or girders, along with suitable section properties, is a common subject for structural optimization studies. This thesis focuses on self-supported dome roofs for fuel storage tanks, and a variety of optimization techniques are adapted, developed and compared. Various load conditions have been compared using detailed fluid and stress analysis in ANSYS. From results for full and empty storage tanks, with wind and/or snow external loads, the worst cases are for wind loading alone, i.e., snow loading counters the lift force from the wind. Consequently, the case of an empty fuel storage tank subject to wind loading is used as the basis for the structural optimization. To speed up the optimization, a simplified frame analysis was developed in Matlab and integrated with the optimization code. In addition, the wind loads were modelled in ANSYS for a range of dome radii and imported into the Matlab, and a number of different dome designs were used as case studies: these were ribbed, Schwedler, Lamella and geodesic. The principal method used to optimize the frame is Morphing Evolutionary Structural Optimization (MESO), in which an initial overdesigned frame is iteratively analysed and reduced in overall weight by reducing the sections of key frame members. The frame is progressively weakened, but without compromising the structural integrity, until it is no longer possible to reduce the weight. However, there are additional parameters that MESO is not suited to, such as dome radius and those affecting the overall structure of the dome frame (numbers and placements of rings, etc.), and a variety of metaheuristic optimization techniques have been studied: Artificial Bee Colony (ABC), Bees Algorithm (BA), Differential Evolution (DE), Particle Swarm Optimization (PSO) and Simulated Annealing (SA). These can be used instead of MESO, or in a hybrid form where MESO optimizes the frame member sections. Although the focus in this thesis is on minimizing the total structural weight, the importance of other characteristics of the design, especially structural stiffness, is considered and also integrated with the MESO process. The hybrid methods MESO-ABC and MESO-DE performed best overall.Higher Committee for Education Development (HCED), IRA

Design of an Instrument to Measure Indigenous Cultural Identity: Case Study on the Waorani Amazonian Nationality

Los indígenas latinoamericanos han sufrido cambios de identidad cultural, en especial a partir del contacto con culturas de Occidente. Para determinar el grado de cambio de identidad cultural es necesario disponer de un instrumento de medida. En la Amazonía, las dificultades para obtener datos de campo no han permitido establecer indicadores culturales. Este trabajo presenta un instrumento diseñado desde la óptica indígena que permite medir su identidad cultural. El estudio cualitativo enfocado en la Amazonía ecuatoriana dio como resultado un instrumento que aporta información de treinta subescalas y cinco escalas culturales, y fue sometido exitosamente a pruebas de validez y de fiabilidad. Por último, fue aplicado a tres poblaciones de diferente grado de contacto con la sociedad occidental para determinar sus diferencias.Latin American indigenous people have undergone changes in their cultural identity, especially as a result of their contact with Western cultures. As such, a measuring instrument is required to determine the extent of this change. In the Amazon, difficulties in obtaining field data have not allowed the establishment of cultural indicators. This paper presents an instrument designed from the indigenous perspective that allows us to measure their cultural identity. The qualitative study focusing on the Ecuadorian Amazon resulted in an instrument that provides information on thirty subscale and five cultural scales, and was successfully tested for validity and reliability. Finally, it was applied to three populations with different degrees of contact with Western society in order to determine their differences

Diseño de un instrumento para medir identidad cultural indígena: caso de estudio sobre la nacionalidad amazónica Waorani

Los indígenas latinoamericanos han sufrido cambios de identidad cultural, en especial a partir del contacto con culturas de Occidente. Para determinar el grado de cambio de identidad cultural es necesario disponer de un instrumento de medida. En la Amazonía, las dificultades para obtener datos de campo no han permitido establecer indicadores culturales. Este trabajo presenta un instrumento diseñado desde la óptica indígena que permite medir su identidad cultural. El estudio cualitativo enfocado en la Amazonía ecuatoriana dio como resultado un instrumento que aporta información de treinta subescalas y cinco escalas culturales, y fue sometido exitosamente a pruebas de validez y de fiabilidad. Por último, fue aplicado a tres poblaciones de diferente grado de contacto con la sociedad occidental para determinar sus diferencias.Latin American indigenous people have undergone changes in their cultural identity, especially as a result of their contact with Western cultures. As such, a measuring instrument is required to determine the extent of this change. In the Amazon, difficulties in obtaining field data have not allowed the establishment of cultural indicators. This paper presents an instrument designed from the indigenous perspective that allows us to measure their cultural identity. The qualitative study focusing on the Ecuadorian Amazon resulted in an instrument that provides information on thirty subscale and five cultural scales, and was successfully tested for validity and reliability. Finally, it was applied to three populations with different degrees of contact with Western society in order to determine their differences.Os indígenas latino-americanos têm sofrido mudanças de identidade cultural, em especial, a partir do contato com culturas do Ocidente. Para determinar o grau de mudança de identidade cultural, é necessário dispor de instrumentos de medição. Na Amazônia, as dificuldades para obter dados de trabalhos de campo não permitem estabelecer indicadores culturais. Este trabalho apresenta um instrumento elaborado sob a ótica indígena que permite medir sua identidade cultural. O estudo qualitativo focado na Amazônia equatoriana resultou num instrumento que contribui com informação de 30 subescalas e cinco escalas culturais, e foi submetido, com sucesso, a testes de validade e confiabilidade. Por último, foi aplicado a três povos de diferentes graus de contato com a sociedad

Applied Metaheuristic Computing

For decades, Applied Metaheuristic Computing (AMC) has been a prevailing optimization technique for tackling perplexing engineering and business problems, such as scheduling, routing, ordering, bin packing, assignment, facility layout planning, among others. This is partly because the classic exact methods are constrained with prior assumptions, and partly due to the heuristics being problem-dependent and lacking generalization. AMC, on the contrary, guides the course of low-level heuristics to search beyond the local optimality, which impairs the capability of traditional computation methods. This topic series has collected quality papers proposing cutting-edge methodology and innovative applications which drive the advances of AMC