Author: MICHEL GARCIA GARCIA

Evaluación del riesgo por contaminantes criterio y formaldehído en la ciudad de México

Agustin Garcia Michel Grutter DANIEL CINTORA JUAREZ (2007)

Se elaboró un estudio de riesgo ambiental para la Ciudad de México sobre contaminantes criterio (O3, NO2, SO2 y PM10) y formaldehído (HCHO). La metodología utiliza en el caso de efectos no cancerígenos el índice de peligrosidad (IP), para el caso de efectos cancerígenos la probabilidad de cáncer en el tiempo de vida (R) y la pérdida de esperanza de vida (PEV). Estos estimados cuantitativos pueden aplicarse a otras ciudades, y tienen la capacidad de indicar que contaminantes pueden afectar a la salud a partir de las concentraciones medidas. Se encontró que el formaldehído es un compuesto importante en la degradación de la calidad del aire para la zona de estudio, teniendo un índice de peligrosidad de 3.4 en exposición crónica para la población con una probabilidad de riesgo de cáncer de 61.2×10-6 y una pérdida de esperanza de vida de 67 días. Por otra parte, el ozono representa el contaminante más influyente en el caso de exposición aguda ya que llega a tener un índice de peligrosidad mayor a 1 para algunas horas del día.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA riesgo ambiental Ciudad de México formaldehído contaminación atmosférica

Evaluación del riesgo por contaminantes criterio y formaldehído en la ciudad de México

Agustin Garcia Michel Grutter DANIEL CINTORA JUAREZ (2007)

Se elaboró un estudio de riesgo ambiental para la Ciudad de México sobre contaminantes criterio (O3, NO2, SO2 y PM10) y formaldehído (HCHO). La metodología utiliza en el caso de efectos no cancerígenos el índice de peligrosidad (IP), para el caso de efectos cancerígenos la probabilidad de cáncer en el tiempo de vida (R) y la pérdida de esperanza de vida (PEV). Estos estimados cuantitativos pueden aplicarse a otras ciudades, y tienen la capacidad de indicar que contaminantes pueden afectar a la salud a partir de las concentraciones medidas. Se encontró que el formaldehído es un compuesto importante en la degradación de la calidad del aire para la zona de estudio, teniendo un índice de peligrosidad de 3.4 en exposición crónica para la población con una probabilidad de riesgo de cáncer de 61.2×10-6 y una pérdida de esperanza de vida de 67 días. Por otra parte, el ozono representa el contaminante más influyente en el caso de exposición aguda ya que llega a tener un índice de peligrosidad mayor a 1 para algunas horas del día.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA riesgo ambiental Ciudad de México formaldehído contaminación atmosférica

Determine routes using an algorithm search with information in a simulated environment using player / stage and robot Pioneer

MICHEL GARCIA GARCIA CINHTIA MARIBEL GONZALEZ SEGURA SERGIO ALEJANDRO GONZALEZ SEGURA (2015)

In this paper it implements a depth-first search algorithm performed in the C ++ programming language implemented on the Player / Stage, that allows the use of a robot Pioneer in a simulated environment. The program developed solves a maze that was represented as a binary tree; the results show a solution to the maze with path previously found, the robot travels the map from an initial state, and using its sensors to detect obstacles, the robot take a decision based on the information obtained with his sensors to solve map, same that allows you to reach a destination point.

Article

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS stage Robot Pionner Simulated environment Depth search Maze search

Generation of maps using a Pioneer 2DX mobile robot in a simulated environment player/stage

JOSE GUILLERMO CEME CANUL MICHEL GARCIA GARCIA CINHTIA MARIBEL GONZALEZ SEGURA SERGIO ALEJANDRO GONZALEZ SEGURA (2014)

This paper describes the implementation of an algorithm that creates maps of an unknown environment for a robot. The algorithm is tested using a model of the Pioneer 2DX mobile robot found in the Player/Stage simulator, and a virtual environment that reflects a real place in the Autonomous University of Yucatan. The tests run simulations of the mobile robot traveling through the virtual environment. A joystick is used to manually control the robot, and a laser sensor is used for the detection of obstacles and walls. Maps obtained using the algorithms are able to represent the environment with the required precision for the robot to navigate.

Article

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS Map building Mobile robot Simulated environment Player stage Pionner 2DX

Supercontinuum Generation in Standard Telecom Fiber Using Picoseconds Pulses

OLIVIER JEAN MICHEL POTTIEZ JUAN CARLOS HERNANDEZ GARCIA (2012)

We reported Supercontinuum (SC) generation in standard telecom fiber using picosecond pulses of microchip

laser. The pulses width is 700 ps at 1064 nm, using 57 m long of standard fiber, and the spectra extend from 700 to

above 1700 nm, some 100 nm further into the visible. The physical processes leading to the formation of the continuum

spectrum were studied by monitoring the growth of the SC while increasing the input power. The coupling efficiency of

ours experimental setup between the microchip laser and the telecom fiber helped us to obtain this wide spectrum.

Conference paper

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Improving the security of Fallahpour’s audio watermarking scheme

JOSE JUAN GARCIA HERNANDEZ CLAUDIA FEREGRINO URIBE RENE ARMANDO CUMPLIDO PARRA RAMON PARRA MICHEL (2010)

The audio watermarking scheme recently proposed by Fallahpour in [1] is one of the schemes with highest payload published to date. In this letter a key-based security improvement is proposed for that scheme. It is achieved by adding a Pseudo-Random Number Sequence (PRNS) in the frequency domain to the data samples, before applying the insertion algorithm. Experimental results show that the proposed enhancement keeps the perceptual transparency and the robustness to all attacks originally reported by Fallahpour’s scheme and the payload is not significantly affected.

Article

Watermarking Spline interpolation Audio signals Keybased security CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES CIENCIA DE LOS ORDENADORES

Polarization stabilization of vector solitons in circularly birefringent fibers induced by Raman effect.

EVGENY KUZIN BALDEMAR IBARRA ESCAMILLA Andrés Gonzalez Garcia OLIVIER JEAN MICHEL POTTIEZ MANUEL DURAN SANCHEZ (2013)

Common optical fibers are randomly birefringent, and solitons traveling in them develop random polarization states

upon propagation. However it is desirable to have solitons with a well-defined polarization. We analyzed the two

coupled propagation equations in a circularly birefringent fiber. Our equations included the soliton self frequency shift.

For our best knowledge this set of equation was analyzed for the first time. We performed a transformation of equations

which reduces them to a form of perturbed Manakov task. The difference between our equations and the integrable

Manakov case was considered as a perturbation. The perturbation method gives us an equations for evolution of the

polarization state of pulse. The evaluation equation shows that in a circularly birefringent (twisted) fiber the cross–

polarization Raman term leads to unidirectional energy transfer from the slow circularly polarized component to the fast

one. The magnitude of this effect is determined by the product of birefringence and amplitudes of both polarization

components. Thus, solitons with any initial polarization state will eventually evolve stable circularly polarized solitons.

We also solved equations using a split-step Fourier method. The parameters of a standard fiber were used with delay

between left- and right- circular polarizations of 1 ps/km that corresponds a fiber twisted by 6 turns/m.

Conference paper

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Dual-wavelength operation of continuous-wave and mode-locked erbium-doped fiber lasers

OLIVIER JEAN MICHEL POTTIEZ ALEJANDRO MARTINEZ RIOS DAVID MONZON HERNANDEZ BALDEMAR IBARRA ESCAMILLA JUAN CARLOS HERNANDEZ GARCIA (2012)

We study numerically and experimentally multiple-wavelength operation of an erbium-doped figure-eight fiber laser

including a multiple-bandpass optical filter formed by two concatenated fiber tapers. Both continuous-wave and pulsed

operations are considered. In the continuous-wave regime, stable long-term operation at multiple closely spaced

wavelengths is only obtained if fine adjustments of the cavity losses are performed. Under these conditions,

simultaneous lasing at up to four wavelengths separated by 1.5 nm was observed experimentally. Tunable singlewavelength

operation over more than 20 nm is also observed in the continuous-wave regime. In the passive mode

locking regime, numerical simulations indicate that mechanisms involving the filter losses and the nonlinear

transmission characteristic of the NOLM contribute in principle to stabilize dual-wavelength operation, allowing less

demanding cavity loss adjustments. In this regime, the problem of synchronization between the pulse trains generated at

each wavelength adds an additional dimension to the problem. In presence of cavity dispersion, the pulses at each

wavelength tend to be asynchronous if the wavelength separation is large, however they can be synchronous in the case

of closely spaced wavelengths, if cross-phase modulation is able to compensate for the dispersion-induced walkoff.

Experimentally, fundamental and 2nd-order harmonic mode locking was observed, characterized by the generation of

noise-like pulses. Finally, a regime of multi-wavelength passive Q-switching was also observed. We believe that this

work will be helpful to guide the design of multiple-wavelength fiber laser sources, which are attractive for a wide range

of applications including Wavelength Division Multiplexing transmissions, signal processing and sensing.

Keywords: Nonlinear Optical Loop Mirror, Wavelength filtering devices, Mode-locked fiber lasers, Erbium fiber lasers

Conference paper

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

EMERGENCIA Y CRECIMIENTO DE PLÁNTULAS DE VARIEDADES DE ALBAHACA (Ocimum basilicum L.) SOMETIDAS A ESTRÉS HÍDRICO

CARLOS MICHEL OJEDA SILVERA Alejandra Nieto Garibay ENRIQUE TROYO DIEGUEZ FRANCISCO HIGINIO RUIZ ESPINOZA José Luis García Hernández (2014)

La poca disponibilidad de agua para la agricultura en las zonas áridas del mundo, y en especial en México, debido a la demanda cada vez mayor de la población en constante aumento, exige realizar estudios encaminados a lograr producciones agrícolas mayores con menos recursos hídricos. Este estudio se realizó con el objetivo de determinar el efecto del estrés hídrico en 20 variedades de albahaca, sometidas a tres niveles de potencial hídrico (0, -0,75 y -1.50 MPa) en un diseño completamente al azar con cuatro repeticiones. Las variables medidas fueron porcentaje y tasa de emergencia, longitud de radícula, altura de plántula, biomasa fresca y seca de radícula, y de la parte aérea. Los resultados mostraron que la variedad con mayor porcentaje y tasa de emergencia bajo estrés fue Red Rubin, en tanto que Mrs Burns no logró la emergencia a un nivel de estrés severo (-1.50 MPa). Thai, Dark Opal, Emily, Dolly y Napoletano presentaron mayor longitud de radícula cuando se les aplicó estrés hídrico; por su parte, Cinnamon, Purple Ruffles, Genovese, Genovese Italian, Dolce Vita y Napoletano no lograron desarrollarse cuando el potencial hídrico se igualó a -1.50 MPa, mientras que Sweet Dani presentó mayor biomasa fresca de parte aérea y radícula. Las variedades de mayor biomasa seca en estrés severo (-1.50 MPa) fueron Siam Queen y Thai en parte aérea; Emily y Thai para radícula en estrés moderado (-0.75 MPa).

Article

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Sequía Semilla Tasa de emergencia Hierbas aromáticas

Activation of Methanogenesis by Cadmium in the Marine Archaeon Methanosarcina acetivorans.

Elizabeth Lira Silva Michel Geovanni Santiago Martinez Viridiana Hernández Rodolfo Garcia Contreras Rafael Moreno Sanchez Ricardo Jasso Chavez (2012)

Methanosarcina acetivorans was cultured in the presence of CdCl(2) to determine the metal effect on cell growth and biogas production. With methanol as substrate, cell growth and methane synthesis were not altered by cadmium, whereas with acetate, cadmium slightly increased both, growth and methane rate synthesis. In cultures metabolically active, incubations for short-term (minutes) with 10 µM total cadmium increased the methanogenesis rate by 6 and 9 folds in methanol- and acetate-grown cells, respectively. Cobalt and zinc but not copper or iron also activated the methane production rate. Methanogenic carbonic anhydrase and acetate kinase were directly activated by cadmium. Indeed, cells cultured in 100 µM total cadmium removed 41-69% of the heavy metal from the culture and accumulated 231-539 nmol Cd/mg cell protein. This is the first report showing that (i) Cd(2+) has an activating effect on methanogenesis, a biotechnological relevant process in the bio-fuels field; and (ii) a methanogenic archaea is able to remove a heavy metal from aquatic environments.

Article

Ecología Metanógenos Cadmio Metano Metales pesados Contaminación del agua BIOLOGÍA Y QUÍMICA