The new approach to designing of innovative thin-walled structures

Для визначення раціональних технічних рішень для інноваційних виробів, у складі яких є тонкостінні машинобудівні конструкції, запропоновано постадійний процес. Цей процес передбачає визначення структури і параметрів тонкостінних машинобудівних конструкцій, які задовольняють традиційним критеріям та обмеженням. Надалі здійснюється варіативний аналіз та будується функція відгуку, яка характеризує залежність техніко-економічних показників від варіювання певної групи параметрів. Після цього проектні параметри обираються із умови незначної зміни техніко-економічних показників при варіюванні проектних та економічних умов. Завдяки такій процедурі визначається технічне рішення та проектні параметри, які забезпечують задовільні техніко-економічні показники для визначеної області варіювання усіх обставин життєвого циклу виробу.To determine the rational technical solutions for innovative products, which include thin-walled machine-building constructions, a fast-moving process is proposed. This process involves structure and parameters determining of thin-walled engineering constructions that meet the traditional criteria and constraints. Then the variational analysis is carried out and a response function is constructed, which characterizes dependence of technical and economic factors on parameters variation. After that, design parameters are chosen from condition of slight technical and economic factors change with variation of design and economic conditions. This procedure determines the technical solution and design parameters that provide satisfactory technical and economic performance for a given region of all circumstances variation in the product life cycle

Time-dependent trading strategies in a continuous double auction

We model a continuous double auction with heterogenous agents and compute approximate optimal trading strategies using evolution strategies. Agents privately know their values and costs and have a limited time to transact. We focus on equilibrium strategies that are developed taking into account the number of traders that submitted orders previously, as well as the number of who will submit subsequently. We find that it is optimal to place increasingly aggressive orders, according to a roughly linear schedule, and test the resulting equilibrium for robustness and accuracy.Continuous double auction, equilibrium trading strategies, evolution strategies.

CONTAINER LOADING ALLOCATION TO IMPROVE SPACE AND LOADING UTILIZATION OF FLEET COMPARTMENT CAPACITY BY USING GENETIC ALGORITHM

PT. XYZ is the current leading automotive company, the supplier that is part of its subsidiary company provides services in form of supply and distribution of raw material. Based on data collected from January till March, the problem appears is the compartment fleet utilization that is far from the maximum capacity. According to the plan production control department, the desired average loading utilization is 16 ton per delivery, while the average loading utilization is 42% or 6,8 ton per delivery. In addition, there are also some deliveries exceeding maximum capacity allowed. Therefore in this research, the most suitable loading pattern is needed to improve utilization of fleet compartment with heterogeneous fleet and heterogeneous material dimension. Loading pattern is also needed as supporting tools for the department by considering weight limit, physical dimension of material and compartment fleet dimension, so that overloaded and unburdened deliveries can be avoided. The research is conducted in plan production control department to gain more information about the fleet, production demand, and raw material properties. Genetic algorithm is used as method for solving the problem and visualize the loading pattern by using Matlab. The calculation is conducted toward loading and space utilization of compartment fleet. From the research, the utilization of space can be optimized to 6% and loading utilization can be optimized up to 50%

Tuning struggle strategy in genetic algorithms for scheduling in computational grids

Job Scheduling on Computational Grids is gaining importance due to the need for efficient large-scale Grid-enabled applications. Among different optimization techniques addressed for the problem, Genetic Algorithm (GA) is a popular class of solution methods. As GAs are high level algorithms, specific algorithms can be designed by choosing the genetic operators as well as the evolutionary strategies. In this paper we focus on Struggle GAs and their tuning for the scheduling of independent jobs in computational grids. Our results showed that a careful hash implementation for computing the similarity of solutions was able to alleviate the computational burden of Struggle GA and perform better than standard similarity measures.Peer ReviewedPostprint (published version

Diseño De Los Parámetros De Un Estabilizador De Sistemas De Potencia (PSS) Basado En Una Técnica Evolutiva

En este artículo se presenta un método de diseño basado en un algoritmo evolutivo para encontrar los parámetros de un estabilizador del sistema de potencia clásico PSS. Se utiliza una técnica evolutiva que realiza un ajuste a los parámetros del PSS. El análisis de los autovalores y los resultados de la simulación lineal y no lineal muestran la efectividad del método en el amortiguamiento de oscilaciones del sistema de potencia, ampliando los límites de estabilidad. El análisis fue realizado sobre una máquina síncrona conectada a un barraje infinito (SMIB, single machine infinite bus power system)