Search results for " algorithms"

Fuzzy predictive controller design using ant colony optimization algorithm

2014

In this paper, an approach for designing an adaptive fuzzy model predictive control (AFMPC) based on the Ant Colony Optimization (ACO) is studied. On-line adaptive fuzzy identification is used to identify the system parameters. These parameters are used to calculate the objective function based on predictive approach and structure of RST control. The optimization problem is solved based on an ACO algorithm, used at the optimization process in AFMPC to calculate a sequence of future RST control actions. The obtained simulation results show that proposed approach provides better results compared with Proportional Integral-Ant Colony Optimization (PI-ACO) controller and adaptive fuzzy model pr…

A GRASP algorithm for the container stowage slot planning problem

2016

This work presents a generalization of the Slot Planning Problem which raises when the liner shipping industry needs to plan the placement of containers within a vessel (stowage planning). State-of-the-art stowage planning relies on a heuristic decomposition where containers are first distributed in clusters along the vessel. For each of those clusters a specific position for each container must be found. Compared to previous studies, we have introduced two new features: the explicit handling of rolled out containers and the inclusion of separations rules for dangerous cargo. We present a novel integer programming formulation and a Greedy Randomized Adaptive Search Procedure (GRASP) to solv…

Task scheduling control of BGA solder joint process in flexible manufacturing system

2006

This paper describes an open loop control method of the solder joint process in a rework station for faulty printed circuit board (PCBs) containing electronic components in packages ball grid arrays (BGAs). In particular, a mathematical model describing the solder joint process is, first of all, obtained. Then, the desired thermal profile of the junctions BGA-PCB is determined according to the physical constraints of the rework station framework. The control parameters corresponding to the above desired thermal profile are identified using the above mathematical model. Finally, the open loop control algorithm is implemented on the supervisor interface of the rework station in order to carri…

Backcalculation of airport pavement moduli and thickness using the Lévy Ant Colony Optimization Algorithm

2016

Interpretation of NDTdata is crucial in any Airport Pavement Management System (APMS), in order to implement strategies to maintain airport pavementssince they allow to estimate their remaining life and related maintenance needs and activities. In this paper, the AntColony Optimization algorithmwasused for backcalculation of pavement moduli from surface deflection data. The algorithm’s performances are illustrated and improvement in prediction quality is demonstrated both in terms of goodness of fitness and computational effort. Moreover, it is proved that the proposed algorithm is also able to predict layer thicknesses, taking into account their variation too.

An Application of Ant Colony Optimization to Decision Making on Affective Virtual Entities

2007

Learning is a never ending activity for humans; it takes place everywhere and even when we do not realize. However, current learning environments make students deal with lectures, mostly associated with low control of the situation and implicit motivation. In contrast, previous researches have shown that sports, games or hobbies are activities that make people reach optimal experiences where self-motivation, control of the situation, high level of concentration and enjoyment are present. Some current efforts to design next generation of learning environments make use of ubiquitous systems to encourage students to perform learning activities everywhere and at anytime. However, those approach…

Evolutionary design optimization with Nash games and hybridized mesh/meshless methods in computational fluid dynamics

2012

AGO Algorithms for the Treatment of Breast Cancer: Update 2021

2021

Geburtshilfe und Frauenheilkunde 81(10), 1101-1111 (2021). doi:10.1055/a-1519-7089

An Integrated fuzzy Cells-classifier

2006

The term soft-computing has been introduced by Zadeh in 1994. Soft-computing provides an appropriate paradigm to program malleable and smooth concepts. In this paper a genetic algorithm is proposed to fuse the classification results due to different distance functions. The combination is based on the optimization of a vote strategy and it is applied to cells classification.

Strategies for accelerating ant colony optimization algorithms on graphical processing units

2007

Ant colony optimization (ACO) is being used to solve many combinatorial problems. However, existing implementations fail to solve large instances of problems effectively. In this paper we propose two ACO implementations that use graphical processing units to support the needed computation. We also provide experimental results by solving several instances of the well-known orienteering problem to show their features, emphasizing the good properties that make these implementations extremely competitive versus parallel approaches.

On the Greedy Algorithm for the Shortest Common Superstring Problem with Reversals

2015

We study a variation of the classical Shortest Common Superstring (SCS) problem in which a shortest superstring of a finite set of strings $S$ is sought containing as a factor every string of $S$ or its reversal. We call this problem Shortest Common Superstring with Reversals (SCS-R). This problem has been introduced by Jiang et al., who designed a greedy-like algorithm with length approximation ratio $4$. In this paper, we show that a natural adaptation of the classical greedy algorithm for SCS has (optimal) compression ratio $\frac12$, i.e., the sum of the overlaps in the output string is at least half the sum of the overlaps in an optimal solution. We also provide a linear-time implement…