Search results for "Genetic algorithm"

A hybrid genetic algorithm with local search: I. Discrete variables: optimisation of complementary mobile phases

2001

Abstract A hybrid genetic algorithm was developed for a combinatorial optimisation problem. The assayed hybridation modifies the reproduction pattern of the genetic algorithm through the application of a local search method, which enhances each individual in each generation. The method is applied to the optimisation of the mobile phase composition in liquid chromatography, using two or more mobile phases of complementary behaviour. Each of these phases concerns the optimal separation of certain compounds in the analysed mixture, while the others can remain overlapped. This optimisation approach may be useful in situations where full resolution with a single mobile phase is unfeasible. The o…

Designing Paper Machine Headbox Using GA

2003

Abstract A non-smooth biobjective optimization problem for designing the shape of a slice channel in a paper machine headbox is described. The conflicting goals defining the optimization problem are the ones determining important quality properties of produced paper: 1) basis weight should be even and 2) the wood fibers of paper should mainly be oriented to the machine direction across the width of the whole paper machine. The novelty of the considered approach is that maximum deviations are used instead of least squares when objective functions are formed. For the solution of this problem, a multiobjective genetic algorithm based on nondominated sorting is considered. The numerical results…

An advanced pavement management system based on a genetic algorithm for a motorway network

2013

Maintenance and improvement, through the rehabilitation, of the road infrastructure is a strategic and priority objective for road agencies, nevertheless the economic resources required are often inadequate. Within road management, the pavement management system (PMS) plays an essential role because of both the money needed and the performance that should be provided in terms of safety, ride quality and transport cost. The PMS is based on searching for a balanced solution between the lowest cost and the increased level of performance (i.e. pavement condition). In this paper a PMS multi-objective optimization method, was proposed, using a genetic algorithm (GA) to identify the best solution …

A Domain Decomposition/Nash Equilibrium Methodology for the Solution of Direct and Inverse Problems in Fluid Dynamics with Evolutionary Algorithms

2008

Optimization of Permanent Magnet Shape for Minimum Cogging Torque Using a Genetic Algorithm

2004

The paper presents an approach to minimization of the cogging torque in permanent magnet (PM) machines using surface-mounted magnets with discrete skew angle. For the purpose of determining the proper arrangement of PM-pole slices, an optimization procedure based on a genetic algorithm is applied. The torque and objective function are determined from a simplified model for torque calculation only partially supported by three-dimensional (3-D) field solution. The results are validated against the 3-D finite-element model as well as experimental data obtained from a prototype machine. A new outer-rotor brushless dc motor motor for an electric fan is considered as a sample model.

Expertise and Skill in Minimally Invasive Surgery

2009

New attitudes to medical ethics and demands for efficiency have brought increased attention to surgical skills and training. It is important to characterize the expertise and skill involved in the multidimensional surgical profession. At a time of change, there is a need to discuss the nature of surgical expertise, and also the prospects for resident training, with special reference to new minimally invasive techniques (MIS). In this paper, we selectively review knowledge on surgical expertise and the specific demands placed on a skilled MIS surgeon. In addition, the review contains a selection of studies from those areas that have been seen as important for the future of training in surge…

Population trends and habitat selection of threatened marsh passerines in a protected Mediterranean wetland

2021

2014

This paper investigates an evolutionary-based designing system for automated sizing of analog integrated circuits (ICs). Two evolutionary algorithms, genetic algorithm and PSO (Parswal particle swarm optimization) algorithm, are proposed to design analog ICs with practical user-defined specifications. On the basis of the combination of HSPICE and MATLAB, the system links circuit performances, evaluated through specific electrical simulation, to the optimization system in the MATLAB environment, for the selected topology. The system has been tested by typical and hard-to-design cases, such as complex analog blocks with stringent design requirements. The results show that the design specifica…

Transmission bottlenecks and the evolution of fitness in rapidly evolving RNA viruses

2003

We explored the evolutionary importance of two factors in the adaptation of RNA viruses to their cellular hosts, size of viral inoculum used to initiate a new infection, and mode of transmission (horizontal versus vertical). Transmission bottlenecks should occur in natural populations of viruses and their profound effects on viral adaptation have been previously documented. However, the role of transmission mode has not received the same attention. Here we used a factorial experimental design to test the combined effects of inoculum (bottleneck) size and mode of transmission in evolution of vesicular stomatitis virus (VSV) in tissue culture, and compared our results to the predictions of a …

Total retinal detachment caused by a KIF11 mutation.

2017

Purpose This is a case report of bilateral retinal detachment associated with KIF11 mutation. Methods In our university hospital, an 8-week-old patient presented with a potential bilateral congenital cataract, iris atrophy, and iridocorneal contact in the left eye. An examination revealed microcephaly and edema of the dorsa of the feet. The eye examination showed a clear lens in both eyes with a dislodged anterior chamber in the left eye with vessels drawn from the iris to the lens. A retrolental white bilateral mass with vessels was also observed. The MRI and the ultrasound revealed a potential peritoneal hyperplastic glass body. Bilateral retinal detachment was diagnosed during surgery. R…