Author
Thiago de Castro Martins
Bio: Thiago de Castro Martins is an academic researcher from University of São Paulo. The author has contributed to research in topics: Simulated annealing & Electrical impedance tomography. The author has an hindex of 17, co-authored 95 publications receiving 771 citations.
Papers published on a yearly basis
Papers
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TL;DR: In the proposed SA algorithm, the sensitivity of each continuous parameter is evaluated at each iteration increasing the number of accepted solutions, and each parameter is associated to its probability distribution in the definition of the next candidate.
Abstract: Simulated annealing (SA) is an optimization technique that can process cost functions with degrees of nonlinearities, discontinuities and stochasticity It can process arbitrary boundary conditions and constraints imposed on these cost functions The SA technique is applied to the problem of robot path planning Three situations are considered here: the path is represented as a polyline; as a Bezier curve; and as a spline interpolated curve In the proposed SA algorithm, the sensitivity of each continuous parameter is evaluated at each iteration increasing the number of accepted solutions The sensitivity of each parameter is associated to its probability distribution in the definition of the next candidate
62 citations
TL;DR: A review of some procedures that are contributing to improve spatial resolution and material properties accuracy, admitivitty or impeditivity accuracy of Electrical Impedance Tomography is presented.
54 citations
TL;DR: A variation of SA is proposed in which the objective function is evaluated only partially, while ensuring boundaries on the behavior of the modified algorithm.
Abstract: Electrical impedance tomography (EIT) is an imaging technique that attempts to reconstruct the impedance distribution inside an object from the impedance between electrodes placed on the object surface. The EIT reconstruction problem can be approached as a nonlinear nonconvex optimization problem in which one tries to maximize the matching between a simulated impedance problem and the observed data. This nonlinear optimization problem is often ill-posed, and not very suited to methods that evaluate derivatives of the objective function. It may be approached by simulated annealing (SA), but at a large computational cost due to the expensive evaluation process of the objective function, which involves a full simulation of the impedance problem at each iteration. A variation of SA is proposed in which the objective function is evaluated only partially, while ensuring boundaries on the behavior of the modified algorithm.
44 citations
TL;DR: A crystallization heuristic is proposed, in order to increase the number of accepted solutions in the problem of minimizing the waste of space that occurs on a rotational placement of a set of irregular two dimensional polygons inside a two dimensional container.
Abstract: This work deals with the problem of minimizing the waste of space that occurs on a rotational placement of a set of irregular two dimensional polygons inside a two dimensional container. This problem is approached with an heuristic based on simulated annealing. Traditional ''external penalization'' techniques are avoided through the application of the no-fit polygon, that determinates the collision free area for each polygon before its placement. The simulated annealing controls: the rotation applied, the placement and the sequence of placement of the polygons. For each non placed polygon, a limited depth binary search is performed to find a scale factor that when applied to the polygon, would allow it to be fitted in the container. It is proposed a crystallization heuristic, in order to increase the number of accepted solutions. The bottom left and larger first deterministic heuristics were also studied. The proposed process is suited for non convex polygons and containers, the containers can have holes inside.
43 citations
TL;DR: In this article, the skip-m current pattern is defined as a pair-wise injection strategy in which the number of non-current injecting electrodes enclosed between two injection electrodes is m.
41 citations
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TL;DR: Several new operations/improvements such as the particle update method based on random sampling and uniform mutation, the infeasible archive, the constrained domination relationship based on collision times with obstacles, are incorporated into the proposed algorithm to improve its effectiveness.
328 citations
23 May 2017
TL;DR: The present article focuses on the study of the intelligent navigation techniques, which are capable of navigating a mobile robot autonomously in static as well as dynamic environments.
Abstract: Mobile robot is an autonomous agent capable of navigating intelligently anywhere using sensor actuator control techniques The applications of the autonomous mobile robot in many fields such as industry space defence and transportation and other social sectors are growing day by day The mobile robot performs many tasks such as rescue operation patrolling disaster relief planetary exploration and material handling etc Therefore an intelligent mobile robot is required that could travel autonomously in various static and dynamic environments Several techniques have been applied by the various researchers for mobile robot navigation and obstacle avoidance The present article focuses on the study of the intelligent navigation techniques which are capable of navigating a mobile robot autonomously in static as well as dynamic environments
175 citations
TL;DR: A new method of global path planning by combining BBO, PSO and approximate voronoi boundary network (AVBN) in a static environment is presented and results in simulation show that the proposed method is feasible and effective.
116 citations
TL;DR: A methodology that hybridizes cuckoo search and guided local search optimization techniques is proposed, which aims to minimize the length of the sheet while having all polygons inside the sheet without overlap.
97 citations