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Improved Modified Bacterial Foraging Optimization Algorithm to Solve Constrained Numerical Optimization Problems

Betania Hernández Ocaña (2016)

This paper presents an improved version of the modified bacterial foraging optimization algorithm to solve constrained numerical optimization problems. Four mechanisms are added: (1) two swim operators, one to favor the exploration and another one to focus on the exploitation of the search space, where a dynamic mechanism is considered to deal with the stepsize value, (2) a skew mechanism for a more suitable initial swarm where bacteria are divided in three groups, two of them close to the boundaries of the search space and one distributed in all the search space, (3) a local search operator and (4) a decrease in the usage of the reproduction step to deal with premature convergence. 60 well-known test problems from two benchmarks are solved along three experiments. The first experiment aims to provide preliminary evidence on the suitable behavior of the new mechanism added. The second experiment provides an in-depth comparison of the new version against its previous one based on final results and four performance measures. The third experiment compares the performance of the proposed algorithm against five state-of-the-art nature-inspired algorithms designed to deal with constrained continuous search spaces. The results show that the proposed algorithm clearly provides a better performance against its predecessor by increasing its ability to reach the feasible region and generating better solutions, while obtaining a competitive performance against those compared state-of-the-art algorithms.

Article

Article

INGENIERÍA Y TECNOLOGÍA Nature-inspired optimization evolutionary algorithms swarm intelligence constrained optimization

Improved Modified Bacterial Foraging Optimization Algorithm to Solve Constrained Numerical Optimization Problems

Betania Hernandez Ocaña (2016)

This paper presents an improved version of the modified bacterial foraging optimization algorithm to solve constrained numerical optimization problems. Four mechanisms are added: (1) two swim operators, one to favor the exploration and another one to focus on the exploitation of the search space, where a dynamic mechanism is considered to deal with the stepsize value, (2) a skew mechanism for a more suitable initial swarm where bacteria are divided in three groups, two of them close to the boundaries of the search space and one distributed in all the search space, (3) a local search operator and (4) a decrease in the usage of the reproduction step to deal with premature convergence. 60 well-known test problems from two benchmarks are solved along three experiments. The first experiment aims to provide preliminary evidence on the suitable behavior of the new mechanism added. The second experiment provides an in-depth comparison of the new version against its previous one based on final results and four performance measures. The third experiment compares the performance of the proposed algorithm against five state-of-the-art nature-inspired algorithms designed to deal with constrained continuous search spaces. The results show that the proposed algorithm clearly provides a better performance against its predecessor by increasing its ability to reach the feasible region and generating better solutions, while obtaining a competitive performance against those compared state-of-the-art algorithms.

Article

Article

INGENIERÍA Y TECNOLOGÍA Nature-inspired optimization evolutionary algorithms swarm intelligence constrained optimization

Functional first order definability of LRTp

JOSE RAYMUNDO MARCIAL ROMERO José Antonio Hernández Servín (2010)

The language LRTp is a non-deterministic language for exact real number computation. It has been shown that all computable rst order relations in the sense of Brattka are denable in the language. If we restrict the language to single-valued total relations (e.g. functions), all polynomials are denable in the language. This paper is an expanded version of [12] in which we show that the non-deterministic version of the limit operator, which allows to dene all computable rst order relations, when restricted to single-valued total inputs, produces single-valued total outputs. This implies that not only the polynomials are denable in the language but also allcomputable rst order functions.

Article

Ingeniería Exact real-number computation Sequential Computation PCF Semantics of programming lan- guages INGENIERÍA Y TECNOLOGÍA

Reformulation of the fresnel transform to introduce sampling and recovery region control and its acceleration

MODESTO GUADALUPE MEDINA MELENDREZ (2010)

The Fresnel transform has been used in several applications of digital holography to

recover wave fields from digital holograms. Three-dimensional (3D) reconstruction, 3D

recognition and particle tracking velocimetry can be found among these applications.

Depending on the application, the recovered wave fields should satisfy certain

requirements. Sampling rate control (availability to choose the distance between samples in

the recovered wave field) is a requirement for several digital holography applications;

furthermore, recovery region control (availability to choose the size and position of the

recovered wave fields) can be useful since in most applications only a small region of the

wave fields is required. Nevertheless, none of the actual formulations of the Fresnel

transform can be used to control the sampling rate and the recovery region in the same

formulation. There are a few proposals that completely control the sampling rate of the

wave fields to be recovered, but they use the computation of at least a couple of two dimensional

discrete Fourier transforms with dependency between them. This dependency

restricts the minimum execution time that can be achieved.

In this research, it is proved that implementations of the Fresnel transform with a single

two-dimensional discrete Fourier transform can be used to control the sampling rate and the

recovery region of the wave fields and, at the same time, to reduce the required execution

time. In a proposed software alternative, the use of a single two-dimensional discrete

Fourier transform can achieve shorter execution times for most of the practical applications

than the current alternatives if a small flexibility is permitted in the required sampling rate.

Furthermore, a parallel hardware architecture, where the flexibility is not required, is

proposed. The hardware architecture can achieve shorter execution times than any existing

alternative to compute the Fresnel transform.

The new formulation of the Fresnel transform can require computing only a few

coefficients of the two-dimensional discrete Fourier transform applied to an input array

padded with zeros. In order to reduce the execution time required by the new formulation of

the Fresnel transform, an input and/or output pruning method for composite length discrete

Fourier transforms was proposed. The pruning method avoids computing the

multiplications per zero and non required Fourier coefficients.

Doctoral thesis

Fast fourier transforms Embedded systems Fourier transforms computation Wavefront numerical reconstruction Fresnel transform CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES

Indices de salinidad y calidad de las aguas superficiales de Tlaxcala, Puebla y Veracruz

OSCAR RAÚL MANCILLA VILLA (2012)

Tesis (Doctorado en Ciencias, especialista en Hidrociencias).- Colegio de Postgrauados, 2012.

En la actualidad se utiliza prácticamente toda agua disponible para satisfacer los requerimientos de humedad en diferentes cultivos que se explotan activamente en agricultura de riego, utilizándose aguas superficiales y subterráneas de variada composición química y concentración de sales. En Tlaxcala, Puebla y Veracruz son irrigadas más de 1 022 000 ha con diversos cultivos, otros usos del agua son la industria, la geotermia, la acuicultura y la recreación. Para conocer las características fisicoquímicas de estas aguas, se llevó a cabo una investigación de tipo observacional, prospectiva, transversal y descriptiva, con recorridos científicos y muestreos de agua en 2009, 2010 y 2011, con 548 muestras totales. En cada muestra de agua se realizaron 26 determinaciones físico-químicas; pH, temperatura, CE, 12 iones (Ca2+, Mg2+, Na+, K+, CO32-, HCO3-, Cl-, SO42-, B, PO43-, NO3- y SiO2), RSE y PO, metales pesados y microelementos (As, Cd, Cu, Cr, Hg, Ni, Pb y Zn). Con las 14 248 determinaciones se clasificaron las aguas cualitativa y cuantitativamente, con base en la cantidad y el tipo de sales disueltas en éstas. Se realizó un experimento de reconcentración de sales mediante evaporación de agua de tres sitios, con los valores de la evaporación se estimó la vía evolutiva geoquímica que siguen las aguas analizadas. Desde la perspectiva agrícola, por asociación de variables físico-químicas específicas determinadas en aguas, como RAS, PSI y CSR, se hace inferencia sobre los niveles de sodio intercambiable en los suelos, además de establecer efectos cuantitativos de las concentraciones iónicas en los cultivos. La mayoría de las aguas fueron bicarbonatadas-cálcico-magnésicas, presentaron concentraciones iónicas medias y bajas, considerandose recomendables para riego. El contenido de metales pesados no excedió los límites permisibles. La vía geoquímica que siguen las aguas es la vía alcalina bicarbonatada. _______________ SALINITY INDEXES AND SURFACE WATER QUALITY OF TLAXCALA, PUEBLA AND VERACRUZ. ABSTRACT: Currently all water available is practically used to meet the moisture requirements of different crops that are grown intensively in irrigation agriculture using surface and underground water of varying chemical composition and concentration of salts. In Tlaxcala, Puebla and Veracruz over 1 022 000 ha with various crops are irrigated, other water uses are for industrial, geothermal, aqua-cultural and recreational purposes. To know the physicochemical characteristics of these waters, an observational, prospective, transversal and descriptive research was carried out, with scientific tours and water samples in 2009, 2010 and 2011, with 548 total samples. In each water sample 26 physicochemical determinations were performed; pH, temperature, EC, 12 ions (Ca2+, Mg2+, Na+, K+, CO32-, HCO3-, Cl-, SO42-, B, PO43-, NO3- y SiO2), TSD y OP, heavy metals and microelements (As, Cd, Cu, Cr, Hg, Ni, Pb y Zn). With the 14 248 determinations waters were classified qualitatively and quantitatively, based on the amount and type of salts dissolved in them. An experiment of re-concentration of salts by evaporation of water from three sites was conducted, with the values of the evaporation it was estimated the geochemical evolutionary path that water analyzed follows. From the agricultural perspective, by association of specific physicochemical variables determined in waters, such as SAR, ESP, and RSC inference was made about the levels of exchangeable sodium in soils, in addition to establishing quantitative effects of ion concentrations on crops. Most waters were calcium-magnesium-bicarbonate, showed medium and low ionic concentrations, considered recommendable for irrigation. The content of heavy metals did not exceed permissible limits. The geochemical path that waters follow is the alkaline bicarbonate path.

Doctoral thesis

RAS PSI Riego Metales pesados Vía evolutiva geoquímica SAR ESP Irrigation Heavy metals Geochemical evolutionary path Doctorado Hidrociencias CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Applications of evolutionary algorithms in the design automation of analog integrated circuits

ESTEBAN TLELO CUAUTLE IVICK GUERRA GOMEZ MIGUEL AURELIO DUARTE VILLASEÑOR LUIS GERARDO DE LA FRAGA GEORGINA FLORES BECERRA GERARDO REYES SALGADO CARLOS ALBERTO REYES GARCIA GUSTAVO RODRIGUEZ GOMEZ (2010)

During the last decade, evolutionary algorithms (EAs) have shown its usefulness for solving multi-objective optimization problems. In the field of analog Integrated Circuits (ICs), they provide a set of feasible solutions for the optimal synthesis and sizing of different kinds of linear and nonlinear circuits, namely: amplifiers, filters and oscillators. The optimization of these circuits can enhance the performance for signal processing applications in electronics. In this study we present the state of the art in applying EAs for the synthesis and sizing of analog ICs. A survey of the main people working in this field and recent major advances and discoveries are summarized. Some insights on the behavior of EAs in the optimal design automation of analog ICs are given. Finally, several open research problems are listed mainly devoted to improve the electronic design automation tools for analog ICs by applying EAs.

Article

Electronic design automation Evolucionary electronics Evolucionary algorithms Circuit synthesis Circuit sizing Genetic algorithm Non-sorting genetic algorithm Multi-objective evolutionary algorithm Unity-gain cell Current conveyor CMOS integrated circuits CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

Structural characterization of lignin in four cacti wood: Implications of lignification in the growth form and succulence

Jorge Reyes Rivera Ramón Marcos Soto Hernández GONZALO CANCHE ESCAMILLA Teresa Terrazas (2018)

Wood lignin composition strongly depends on anatomical features and it has been used as a marker for characterizing major plant groups. Wood heterogeneity in Cactaceae is involved in evolutionary and adaptive processes within this group; moreover, it is highly correlated to the species growth form. Here we studied the lignin structure from different types of woods in four Cactaceae species with different stem morphologies (Pereskia lychnidiflora, tree/fibrous wood; Opuntia streptacantha and Pilosocereus chrysacanthus, tree/succulent fibrous wood; Ferocactus hamatacanthus, cylindrical stem/dimorphic wood) in order to determine their relationship with the wood anatomy in an evolutionary-adaptive context. Dioxane lignin was isolated and analyzed by pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The main linkages are the β-O−4′ ether (67–85%), the β-β′ resinol (10–26%) and the β-5′ and α-O−4′ linkages of the phenylcoumaran structures (≤7%). Spirodienone structures have a considerable abundance (5%) in the dimorphic wood of F. hamatacanthus. In addition, low contents (≤3%) of α,β-diaryl ether, α-oxidized β-O−4′ ether and dibenzodioxocin structures were found. The sinapyl- and coniferyl acetates are not part of the wood lignin in any of the studied species. The low (≤5%) γ-acetylation in the F. hamatacanthus and P. chrysacanthus wood lignin is here interpreted as an evidence of a high specialization of the wood elements in the conduction/storage of water. The lignin of the studied Cactaceae is composed predominantly of guaiacyl and syringyl units (S/G: 0.9–16.4). High abundance of syringyl units (62–94%) in three of the four species is considered as a defense mechanism against oxidative agents, it is a very conspicuous trait in the most succulent species with dimorphic wood. Furthermore, it is also associated with ferulates and the herein called γ-acetylated guaiacyl-syringaresinol complexes acting as nucleation sites for lignification and as cross-links between lignin and carbohydrates at the wide-band tracheid-fiber junctions.

Article

CACTACEAE DIMORPHIC WOOD EVOLUTIONARY-ADAPTIVE PROCESSES S-RICH LIGNIN STRUCTURAL PROTECTION SUCCULENCE BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA

Applying Crowdsourcing and Human-Computation Paradigms to a Software Project

García Fernández, Alejandro (2012)

Crowdsourcing and Human-Computation are paradigms that are enabling new forms of collaboration between humans and computers. However when developing such a system as there aren’t many guidelines. In this paper we explore what considerations need to be tak

Master thesis

Crowdsourcing, Human-Computation, Book Digitalization CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Ant-Mimicking Spiders: Strategies for Living with Social Insects

Fadia Sara Ceccarelli (2013)

"Mimicry is a fascinating topic, in particular when viewed in terms of selective forces and evolutionary strategies. Mimicry is a system involving a signaller, a signal receiver, and a model and has evolved independently many times in plants and animals. There are several ways of classifying mimicry based on the interactions and cost-benefit scenarios of the parties involved. In this review, I briefly outline the dynamics of the most common types of mimicry to then apply it to some of the spider-ant associative systems known to date. In addition, this review expands on the strategies that ant-associating (in particular ant-mimicking) spiders have developed to minimise the costs of living close to colonies of potentially dangerous models. The main strategy that has been noted to date is either chemical mimicry or actively avoiding contact with ants. If these strategies warrant protection for the spider (living close to potentially dangerous models), then the benefits of ant associations would outweigh the costs, and the association will prevail."

Article

Ant mimicking spiders, Social insects, Mimicry, Evolutionary strategies, Chemical mimicry BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA

Foraging patterns of four sympatric species of silversides (Atheriniformes: Atherinopsidae) in Lago de Pátzcuaro, Central Mexico

FRANCISCO JAVIER GARCIA DE LEON JUAN PABLO RAMIREZ HERREJON Dean A. Hendrickson (2014)

"Since Barbour proposed sympatric speciation to explain evolution of silversides in the Lerma-Santiago basin, relatively little subsequent study has been done. We assessed foraging patterns of four sympatric silversides species (Chirostoma estor, Chirostoma grandocule,Chirostoma attenuatum and Chirostoma patzcuaro) in Lago de Pátzcuaro to understand resource partitioning and their sympatric coexistence. We assessed the abundance of invertebrate prey in three feeding habitats and measured physical and chemical habitat parameters at two study sites. Fish were collected during the wet (September 1987) and dry (March 1988) seasons; a total of 242 gut contents were analyzed. We evaluated the trophic guild of each species using the index of relative importance (IRI), prey selectivity with the Ivlev Electivity Index (E), dietary diversity using Shannon and Wiener diversity index(H’), and diet overlap using Morisita index. All silverside species were determined to be predaceous carnivores that feed mainly on nekton and periphyton. Dietary diversity and prey selectivity patterns were similar among species and diet overlap was >70%. Our data do not support the proposition that coexistence of these four fish species is maintained by dietary specialization. We hypothesize that sympatric coexistence of atherinopsids in Lago de Pátzcuaro is explained by food resource availability and ontogenetic variation in their diets. This study highlights the importance of analyzing ecological patterns and mechanisms as basic elements for designing conservation strategies of species flocks, especially under habitat loss and introduction of exotic species. Conservation efforts are urgent to preserve the rare evolutionary process of sympatric speciation (habitat segregation) that is occurring in other lakes in central Mexico, and probably already lost in the Lago de Pátzcuaro, as a result of poor management and inadequate conservation strategies."

"Desde que Barbour propuso la especiación simpátrica para explicar la evolución de pescados blancos y charles en la cuenca Lerma-Santiago, poco estudios posteriores se ha hecho. Los patrones de forrajeo de cuatro especies simpátricas del género Chirostoma (Chirostoma estor, Chirostoma grandocule, Chirostoma attenuatum y Chirostoma patzcuaro) fueron evaluadas en el Lago de Pátzcuaro, para entender la repartición de recursos alimenticios y su coexistencia simpátrica. La abundancia de invertebrados presa fue estimada en distintos hábitat alimenticios y se midieron parámetros físicos y químicos del hábitat en dos sitios de estudio. Los peces fueron recolectados durante las temporadas de lluvias (Septiembre 1987) y estiaje (Marzo 1988); 242 tractos digestivos fueron analizados. Se revaluó el gremio trófico, la selectividad de las presas, la diversidad y el traslape de dieta. Las cuatro especies fueron determinadas como carnívoros depredadores que se alimentan principalmente de necton y perifiton. La diversidad de la dieta y los patrones de selectividad de presas fueron similares entre los atherinopsidos y el traslape de dieta fue >70%. Los resultados no apoyan la propuesta de que la coexistencia de estas cuatro especies se mantiene por medio de la especialización de su dieta. Se hipotetizó que la coexistencia simpátrica de los atherinopsidos del Lago de Pátzcuaro se explica por la alta disponibilidad de recursos alimenticios y la variación ontogénica de su dieta. Este estudio resalta la importancia de analizar los patrones y mecanismos ecológicos como elementos básicos para el diseño de estrategias de conservación en especies en enjambre, bajo efectos antropogénicos como la pérdida del hábitat y la introducción de especies exóticas. Los esfuerzos de conservación son urgentes para preservar el raro proceso evolutivo de la especiación simpátrica (segregación del hábitat) que ocurre en otros lagos del centro de México, y que posiblemente se ha perdido en el Lago de Pátzcuaro, como resultado del manejo deficiente y estrategias de conservación inadecuadas."

Article

Atherinopsidae, feeding interactions, species flocks, evolutionary process, conservation interacciones alimenticias, especies en enjambre, procesos evolutivos, conservación BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) GENÉTICA ANIMAL