The Ariadne's Clew Algorithm

We present a new approach to path planning, called the "Ariadne's clew algorithm". It is designed to find paths in high-dimensional continuous spaces and applies to robots with many degrees of freedom in static, as well as dynamic environments - ones where obstacles may move. The Ariadne's clew algorithm comprises two sub-algorithms, called Search and Explore, applied in an interleaved manner. Explore builds a representation of the accessible space while Search looks for the target. Both are posed as optimization problems. We describe a real implementation of the algorithm to plan paths for a six degrees of freedom arm in a dynamic environment where another six degrees of freedom arm is used as a moving obstacle. Experimental results show that a path is found in about one second without any pre-processing

The Ariadne's Clew Algorithm

We present a new approach to path planning, called the ``Ariadne's clew algorithm''. It is designed to find paths in high-dimensional continuous spaces and applies to robots with many degrees of freedom in static, as well as dynamic environments --- ones where obstacles may move. The Ariadne's clew algorithm comprises two sub-algorithms, called SEARCH and EXPLORE, applied in an interleaved manner. EXPLORE builds a representation of the accessible space while SEARCH looks for the target. Both are posed as optimization problems. We describe a real implementation of the algorithm to plan paths for a six degrees of freedom arm in a dynamic environment where another six degrees of freedom arm is used as a moving obstacle. Experimental results show that a path is found in about one second without any pre-processing

Laban Movement Analysis Using a Bayesian Model and Perspective Projections

Human body movements are meant to move a, or some, body parts to a specific location along a certain trajectory. A person observing the movement might be able to recognize it through the spatial pathway alone. Kendon (Kendon, 2004) holds the view that willingly or not, humans, when in co-presence, continuously inform one another about their intentions

Biodegradación de ftalatos por Pleurotus ostreatus y Fusarium culmorum crecidos en medio líquido

Los ftalatos son diésteres aromáticos ampliamente utilizados como plastificantes, estos compuestos además de ser contaminantes desempeñan un papel como disruptores endócrinos. El ftalato más empleado es el di (2-etilhexil) ftalato (DEHF), seguido por dibutil ftalato (DBF), estos compuestos han sido detectados en suelo, agua, alimentos, pescado y efluentes industriales. En esta investigación se evaluaron diferentes parámetros para los hongos Fusarium culmorum y Pleurotus ostreatus crecidos en concentraciones de 1000 y 500 mg/l de DEHF y DBF, como la velocidad específica de crecimiento (µ) y la biomasa máxima producida (Xmáx), el consumo de glucosa, la constante de biodegradación (k) para DBF y DEHF la eficiencia de remoción (%), actividades enzimáticas de lacasas y esterasas al igual que los rendimientos de las enzimas con respecto al sustrato (YE/X), la productividad enzimática (P= Emáx/h), la actividad enzimática máxima (Emáx) y la tasa específica de formación de la enzima qp= (μ) (YE/X). Se identificaron diferentes intermediarios en la biodegradación de DEHF y DBF por GC-MS y a partir de eso se propusieron rutas de degradación para estos compuestos empleando un modelo de química cuántica. Fusarium culmorum mostró la mayor μ (0.05 h-1) en el medio con 1000 mg/l de DEHF. Tanto P. ostreatus como F. culmorum consumieron alrededor de un 95 % de la glucosa en los medios que contenían DEHF 1000 mg/l durante las 360 y 144 h de crecimiento, respectivamente. La mayor Xmáx y el mayor YX/S se presentaron tanto para P. ostreatus como para F. culmorum en el medio conteniendo 1000 mg/l de DEHF. Pleurotus ostreatus mostró la mayor Xmáx y el v mayor YX/S obteniendo un valor de 7.69 g/l y 0.76 gX/gS, respectivamente. El pH de los cultivos de P. ostreatus que contenían ftalatos disminuyeron mostrando valores cercanos a un pH de 4. El pH de los cultivos de F. culmorum incrementaron sus valores obteniendo un pH cercano del valor neutro. Pleurotus ostreatus mostró la mayor producción y Emáx de enzimas lacasas en el medio que contenía 1000 mg/l de DEHF, mostrando valores de 11508 U/l. La mayor actividad y Emáx de enzimas esterasas fue de 4765 U/l, producida por el hongo F. culmorum en el medio conteniendo 1000 mg/l de DEHF. Los mayores parámetros cinéticos enzimáticos los presentó P. ostreatus para las enzimas lacasas en el medio conteniendo 1000 mg/l de DEHF. Fusarium culmorum mostró los mayores parámetros cinéticos de enzimas esterasas en los medios que contenían 1000 mg/l de DEHF y DBF. Pleurotus ostreatus y F. culmorum obtuvieron más del 90 % de remoción de ambos ftalatos a partir de las 300 y 72 h de crecimiento, respectivamente. Con base en los estudios de química cuántica se pudo observar que P. ostreatus siguió una ruta de degradación metabolizando el DEHF a ácido ftálico, ácido acético y hexanal. El DBF fue metabolizado a ácido ftálico y ácido acético. Éste, posteriormente, lo mineralizó completamente a CO2. Fusarium culmorum fue capaz de metabolizar el DEHF obteniendo como producto final butanediol y el DBF lo metabolizó a ácido fumárico y ácido málico, metabolitos detectados por GC-MS y analizados por el intercambio de electrones que nos permitió observar el estudio de química cuántica. P. ostreatus y F. culmorum ofrecen un gran potencial en la biorremediación de lugares contaminado con DEHF y DBF, ya que utilizan estos contaminantes como fuente de carbono y energía.Phthalates are aromatic diesters widely used as plasticizers. These compounds are also pollutants and endocrine disruptors. The most commonly used phthalate is di (2 ethylhexyl) phthalate (DEHP), followed by dibutyl phthalate (DBP). These compounds have been detected in soil, water, food, fish and industrial effluents. Growth kinetics (μ and Xmáx), glucose consumption, constant biodegradation (k) for dibutyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP), percentage of removal efficiency, laccases and esterase activities and enzymatic performance were evaluated for Fusarium culmorum and Pleurotus ostreatus grown on media containing glucose and different concentrations of DEHP and DBP (0, 500 and 1000 mg/l). Different intermediates in the biodegradation of DEHP and DBF by GC-MS were identified and degradation pathways for these compounds were proposed using quantum chemical modeling. The greatest µ (0.05 h-1) occurred in media supplemented with 1000 mg/l of DEHP/l. P. ostreatus and F. culmorum consumed 95% of glucose in media containing 1000 mg/l de DEHP/l within 360 and 144 h of growth, respectively. The greatest Xmáx and the largest YX/S occurred in media supplemented with 1000 mg/l of DEHP/l for these fungi. The pH of cultures of P. ostreatus containing phthalates decreased, presenting values close to pH 4 while pH of F. culmorum increased pH close neutral value. The greatest production and laccase activity were observed in media containing 1000 mg/l of DEHP/l for P. ostreatus. The greatest production and esterase activity were observed in media containing 1000 mg/l de DEHP/l for F. culmorum. The higher enzymatic yield parameters occurred in media supplemented with 1000 mg/l de DEHP/l for these fungi. vii These fungi could degrade more than 90% of both phthalates and metabolized to intermediates of different metabolic pathways (Krebs Cycle and butanediol fermentation). The compounds of biodegradation of DEHP were identified by GC˗MS. A DEHP and DBP biodegradation pathway by F. culmorum and P. ostreatus were proposed using quantum chemical modeling. P. ostreatus and F. culmorum offer great potential in bioremediation of sites contaminated with DEHP and DBF as they use these pollutants as carbon and energy source

Los coréos en Chignautla, Puebla: la danza y su relación con las concepciones de la naturaleza

"Los diversos procesos de homogeneización económica, social y cultural que son causados por el actual sistema de globalización mundial han impactado negativamente en la realización de las diversas expresiones dancístico-musicales tradicionales y populares del país. En consonancia a estos fenómenos de estandarización, la Danza de los Coreos de Chignautla, Puebla, ha experimentado un decrecimiento en su realización, así como una paulatina desarticulación con el sistema festivo-religioso de Chignautla, Puebla. Por lo cual se es de vital importancia abordar mediante la investigación etnocoreológica la Danza de los Coreos y su imbricación con la fiesta patronal y el sistema de danzas de la región de Chignautla, Puebla, con los objetivos de evidenciar y comprender los diversos procesos de construcción identitaria que se fundamentan en las complejas relaciones de los actores sociales de Chignautla, Puebla con la divinidad y con la naturaleza"

Allyl 4-hydroxy­phenyl carbonate

The title mol­ecule, C10H10O4, is a functionalized carbonate used in the synthetic route to organic glasses. The central CH fragment of the allyl group is disordered over two positions, with occupancies in a 0.758 (10):0.242 (10)ratio. This disorder reflects the torsional flexibility of the oxygen–allyl group, although both disordered parts present the expected anti­clinal conformation, with O—CH2—CH=CH2 torsion angles of −111 (2) and 119.1 (4)°. The crystal structure is based on chains parallel to [010], formed by O⋯H—O hydrogen bonds involving hydroxyl and carbonyl groups as donors and acceptors, respectively. The mol­ecular packing is further stabilized by two weak C—H⋯π contacts from the benzene ring of the asymmetric unit with two benzene rings of neighboring mol­ecules

General Solutions to Functional and Kinematic Redundancy

A systematic and general approach to represent functional redundancy is presented. It is shown how this approach allows the freedom provided by functional redundancy to be integrated into the inverse geometric problem for real-time applications and how it can be utilised to improve performance. A set of new iterative solutions to the inverse geometric problem, well suited for kinematically redundant manipulators, is also presented

Iterative Solutions to the Inverse Geometric Problem for Manipulators with no Closed Form Solution

A set of new iterative solutions to the inverse geometric problem is presented. The approach is general and does not depend on intersecting axes or calculation of the Jacobian. The solution can be applied to any manipulator and is well suited for manipulators for which convergence is poor for conventional Jacobian-based iterative algorithms. For kinematically redundant manipulators, weights can be applied to each joint to introduce stiffness and for collision avoidance. The algorithm uses the unit quaternion to represent the position of each joint and calculates analytically the optimal position of the joint when only the respective joint is considered. This sub-problem is computationally very efficient due to the analytical solution. Several algorithms based on the solution of this sub-problem are presented. For difficult problems, for which the initial condition is far from a solution or the geometry of the manipulator makes the solution hard to reach, it is shown that the algorithm finds a solution fairly close to the solution in only a few iterations