Evolutionary optimization in dynamic fitness landscape environments

Non-stationary, or dynamic, problems change over time. There exist a variety of forms of dynamism. The concept of dynamic environments in the context of this paper means that the fitness landscape changes during the run of an evolutionary algorithm. Genetic diversity is crucial to provide the necessary adaptability of the algorithm to unexpected changes. Two key concepts to maintain genetic diversity in the population are incorporated to the algorithm and proposed here: macromutation operators and random immigrants. The algorithm was tested on a set of dynamic testing functions provided by a dynamic fitness problem generator. The main goal was to determine the algorithm ability to face changes and dimensional or multimodal scalability in the functions. The effectiveness and limitations of the proposed algorithm in diverse scenarios of a dynamic environment is discussed from results empirically obtained.Eje: Agentes y Sistemas Inteligentes (ASI)Red de Universidades con Carreras en Informática (RedUNCI

Immune Algorithm for Solving the Dynamic Economic Dispatch Problem

In this paper, an algorithm inspired on the immune system is presented, IA DED stands for Immune Algorithm Dynamic Economic Dispatch, it is used to solve the Dynamic Economic Dispatch problem. IA DED uses as differentiation process a redistribution power operator and the output power are integer values. The proposed approach is val- idated using three problems taken from the specialized literature. Our results are compared with respect to those obtained by several other approaches.XVII Workshop Agentes y Sistemas Inteligentes (WASI).Red de Universidades con Carreras en Informática (RedUNCI

Immune Algorithm for Solving the Dynamic Economic Dispatch Problem

In this paper, an algorithm inspired on the immune system is presented, IA DED stands for Immune Algorithm Dynamic Economic Dispatch, it is used to solve the Dynamic Economic Dispatch problem. IA DED uses as differentiation process a redistribution power operator and the output power are integer values. The proposed approach is val- idated using three problems taken from the specialized literature. Our results are compared with respect to those obtained by several other approaches.XVII Workshop Agentes y Sistemas Inteligentes (WASI).Red de Universidades con Carreras en Informática (RedUNCI

Evolutionary optimization in dynamic fitness landscape environments

Non-stationary, or dynamic, problems change over time. There exist a variety of forms of dynamism. The concept of dynamic environments in the context of this paper means that the fitness landscape changes during the run of an evolutionary algorithm. Genetic diversity is crucial to provide the necessary adaptability of the algorithm to unexpected changes. Two key concepts to maintain genetic diversity in the population are incorporated to the algorithm and proposed here: macromutation operators and random immigrants. The algorithm was tested on a set of dynamic testing functions provided by a dynamic fitness problem generator. The main goal was to determine the algorithm ability to face changes and dimensional or multimodal scalability in the functions. The effectiveness and limitations of the proposed algorithm in diverse scenarios of a dynamic environment is discussed from results empirically obtained.Eje: Agentes y Sistemas Inteligentes (ASI)Red de Universidades con Carreras en Informática (RedUNCI

Solving constrained optimization using a T-Cell artificial immune system

In this paper, we present a novel model of an artificial immune system (AIS), based on the process that suffers the T-Cell. The proposed model is used for solving constrained (numerical) optimization problems. The model operates on three populations: Virgins, Effectors and Memory. Each of them has a different role. Also, the model dynamically adapts the tolerance factor in order to improve the exploration capabilities of the algorithm. We also develop a new mutation operator which incorporates knowledge of the problem. We validate our proposed approach with a set of test functions taken from the specialized literature and we compare our results with respect to Stochastic Ranking (which is an approach representative of the state-of-the-art in the area) and with respect to an AIS previously proposed.En este trabajo, se presenta un nuevo modelo de Sistema Inmune Artificial (SIA), basado en el proceso que sufren las células T. El modelo propuesto se usa para resolver problemas de optimización (numéricos) restringidos. El modelo trabaja sobre tres poblaciones: Vírgenes, Efectoras y de Memoria. Cada una de ellas tiene un rol diferente. Además, el modelo adapta dinamicamente el factor de tolerancia para mejorar las capacidades de exploración del algoritmo. Se desarrolló un nuevo operador de mutación el cual incorpora conocimiento del problema. El modelo fue validado con un conjunto de funciones de prueba tomado de la literatura especializada y se compararon los resultados con respecto a Stochastic Ranking (el cual es un enfoque representativo del estado del arte en el área) y con respecto a un SIA propuesto previamente.VIII Workshop de Agentes y Sistemas InteligentesRed de Universidades con Carreras en Informática (RedUNCI

Composite scaffold obtained by electro-hydrodynamic technique for infection prevention and treatment in bone repair

Bone infection is a devastating condition resulting from implant or orthopaedic surgery. Therapeutic strategies are extremely complicated and may result in serious side effects or disabilities. The development of enhanced 3D scaffolds, able to promote efficient bone regeneration, combined with targeted antibiotic release to prevent bacterial colonization, is a promising tool for the successful repair of bone defects. Herein, polymeric electrospun scaffolds composed of polycaprolactone (PCL) nanofibres decorated with poly(lactic-co-glycolic acid) (PLGA) particles loaded with rifampicin were fabricated to achieve local and sustained drug release for more efficient prevention and treatment of infection. The release profile showed an initial burst of rifampicin in the first six hours, enabling complete elimination of bacteria. Sustained and long-term release was observed until the end of the experiments (28 days), facilitating a prolonged effect on the inhibition of bacterial growth, which is in agreement with the common knowledge concerning the acidic degradation of the microparticles. In addition, bactericidal effects against gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacteria were demonstrated at concentrations of released rifampicin up to 58 ppm after 24 h, with greater efficacy against S. aureus (13 ppm vs 58 ppm for E. coli). Cell morphology and cytocompatibility studies highlighted the suitability of the fabricated scaffolds to support cell growth, as well as their promising clinical application for bone regeneration combined with prevention or treatment of bacterial infection

The First VLT FORS1 spectra of Lyman-break candidates in the HDF-S and AXAF Deep Field

We report on low-resolution multi-object spectroscopy of 30 faint targets (R \~ 24-25) in the HDF-S and AXAF deep field obtained with the VLT Focal Reducer/low dispersion Spectrograph (FORS1). Eight high-redshift galaxies with 2.75< z < 4 have been identified. The spectroscopic redshifts are in good agreement with the photometric ones with a dispersion $\sigma_z = 0.07$ at z<2 and $\sigma_z = 0.16$ at z>2. The inferred star formation rates of the individual objects are moderate, ranging from a few to a few tens solar masses per year. Five out of the eight high-z objects do not show prominent emission lines. One object has a spectrum typical of an AGN. In the AXAF field two relatively close pairs of galaxies have been identified, with separations of 8.7 and 3.1 proper Mpc and mean redshifts of 3.11 and 3.93, respectively.Comment: 5 pages Latex, with 2 PostScript figures. Astronomy and Astrophysics, in pres

Global convergence of a non-convex Douglas-Rachford iteration

We establish a region of convergence for the proto-typical non-convex Douglas-Rachford iteration which finds a point on the intersection of a line and a circle. Previous work on the non-convex iteration [2] was only able to establish local convergence, and was ineffective in that no explicit region of convergence could be given

La gestión en la instrumentación de programas de formación y actualización de profesores por la coordinación de formación docente, Facultad de Química, UNAM

En este trabajo se presentan las acciones de gestión que la Coordinación de Formación Docente de la Secretaría de Extensión Académica de la Facultad de Química de la Universidad Nacional Autónoma de México realiza antes, durante y después de la instrumentación de programas de formación y actualización de profesores de ciencias educación básica, en servicio

An Artificial Immune System for Solving Dynamic Economic Power Dispatch Problems

In this paper, we propose an artificial immune system called IA DED, which stands for Immune Algorithm Dynamic Economic Dispatch. It is designed for solving the Dynamic Economic Dispatch (DED) problem. Our approach considers the DED problem as a dynamic problem whose constraints change over time. IA DED considers the activation process that T cells suffer in order to find partial solutions. The proposed approach is validated using several DED problems taken from the specialized literature. Our results are compared with respect to those obtained by other approaches taken from the specialized literature. We also provide some statistical analysis in order to determine the sensitivity of the performance of our proposed approach to its parameters.XX Workshop Agentes y Sistemas Inteligentes.Red de Universidades con Carreras en Informátic