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Miradas sobre dinámicas territoriales en México

EDGAR TALLEDOS SANCHEZ (2016)

"En 1973, Jean Gottmann (1915-1994) arguyó que el concepto de territorio poco se había explorado en la explicación de la “organización política del espacio”, en las relaciones con las comunidades y sus relaciones de vecindad. Hoy esta categoría de análisis es ampliamente usada en las ciencias sociales para explicar diversos fenómenos culturales, económicos y políticos. El libro que aquí se presenta explora este tema, la forma en cómo se ha acondicionado, acomodado, en otras palabras, construido en México."

Review

Asentamientos humanos Territorio nacional – México CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOGRAFÍA GEOGRAFÍA

Transmission function of the collinear acousto-optical filter controlled by acoustic waves of the finite amplitude

ALEXANDER SHCHERBAKOV Adán Omar Arellanes Bernabe (2013)

An opportunity to exploit specific mechanisms of the acousto-optic nonlinearity to regulate performances of the collinear acousto-optical filter, realizing the sequential spectrum analysis of optical signals, is considered. This possibility is theoretically analyzed and experimentally confirmed with an advanced filter based on calcium molybdate (CaMoO4) single-crystal with a 15-μs time-aperture. It is able to operate over red and near-infrared light at relatively low radio-wave frequencies providing almost lossless regime for controlling acoustic waves of the finite amplitude. Under certain conditions, the transmission function of electronically tunable filter exhibits a marked dependence on the applied acoustic power density, and as a result, one can significantly squeeze the transmission function, i.e., improve the spectral resolution of this filter at the cost of decreasing the efficiency of the device partially. The identified and observed non-linear effect makes possible varying the performance data of similar advanced collinear acousto-optical filter governed by external signals of the finite amplitude. © 2013 Society of Photo-Optical Instrumentation Engineers (SPIE) [DOI: 10.1117/1.OE.52.6.064001]

Article

Collinear acousto-optical interaction Optical filter Acousto-optical nonlinearity Transmission function Spectral resolution Waves of the finite amplitude CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Transmission function of collinear acousto-optical interaction occurred by acoustic waves of finite amplitude

ALEXANDER SHCHERBAKOV Adán Omar Arellanes Bernabe (2013)

New physical aspects of collinear acousto-optical interaction, occurred by acoustic waves of finite amplitude, are revealed and analyzed in crystalline materials exhibiting moderate linear acoustic losses. The analysis is performed in the regime of continuous traveling waves allowing a specific mechanism of the acousto-optic nonlinearity. Our consideration has shown that such nonlinearity together with linear acoustic losses is able to affect the transmission function inherent in collinear interaction. In particular, the mere presence of linear acoustic losses by themselves leads to broadening the width of the transmission function beginning already from very low levels of the applied acoustic power. Moreover, the transmission function exhibits a marked and quasi-periodical dependence on the applied acoustic power density, and that periodicity is governed by the linear acoustic losses. As a result, the transmission function can be significantly narrowed near isolated points at the cost of decreasing the interaction efficiency. These novelties related to collinear acousto-optical interaction accompanied by moderate linear acoustic losses have been studied and confirmed experimentally with an advanced acousto-optical cell based on calcium molybdate (CaMoO4) single crystal and controlled by acoustic waves of finite amplitude. © 2013 Optical Society of America

Article

Dynamic gratings Nonlinear optics Parametric processes Acousto-optical devices CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Spatio-temporal land-use changes in the Colima-Villa de Álvarez metropolitan area, and their relationship to floodings

Spatio-temporal land-use changes in the Colima-Villa de Álvarez metropolitan area, and their relationship to floodings

MYRNA LORENA PEREZ GONZALEZ LUCIA CAPRA PEDOL NORMA ANGELICA DAVILA HERNANDEZ LORENZO BORSELLI SARA SOLIS VALDEZ AZALEA JUDITH ORTIZ RODRIGUEZ (2017)

Demographic growth and consequent land-use changes are consid - ered one of the main factors causing inundations in many cities in de - veloping countries. During the last decade, the city of Colima, Mexico, has suffered from an increase in flooding events. These episodes mostly occurred during tropical rainstorms associated to hurricanes (such as Jova in 2011, Manuel in 2013, and Patricia in 2015, all with average accumulated rainfall of 200 mm in 24 h), as well as during short- duration, high-intensity rainfall events at the beginning of the rainy season. To define the mechanisms leading to the increased occurrence of floodings, a space-time analysis of land-use changes, coupled with the characterization of natural and urban soils, are presented here for the Colima metropolitan area. Three land-use categories were created: native land (N1), urban land (N4), and cultivated land (N5). Each of these categories has subcategories depending on vegetative cover and/ or level of urbanization. SPOT imagery acquired in 2005, 2009, and 2015 was classified to analyze the spatial and temporal changes in land use. Thirty-two soil samples representative of different land uses were analyzed to obtain their physical and chemical properties such as granulometry, bulk and particle densities, porosity, and organic matter content. Hydraulic conductivity tests were performed in situ using a drip-infiltrometer device. The temporal and spatial analysis of SPOT images revealed that most changes in land use correspond to urban area and cultivated land, the former showing an increase and the latter a drastic decrease, especially towards the northern part of the city, where urban growth is evident for the 20052009 period. Analyzed soils from cultivated land have the highest permeability, and engineered soils correspond to the least permeable soils in the area; consequently, replacement of agriculture with housing has significant impacts on the rainfall-runoff process. These results indicate that as more permeable land area is substituted by disturbed urban soils, the infiltration capability will be reduced, leading to increasing flooding frequency in the Colima-Villa de Álvarez metropolitan area. To prevent and reduce the disruptive im - pact of inundation in the Colima metropolitan area, it is recommended to have adequate management of land-use change and to conserve the permeable areas around the city. In addition, it is necessary to revise the hydraulic infrastructure of the existing urban areas and to properly define the most suitable locations for future ones. Avoiding develop - ment in flood-prone areas through planning and zoning ordinances may reduce loss of life and damage to property.

Article

Ciencias de la Tierra Flooding land use hydraulic conductivity SPOT images Colima Mexico Ciencias de la Tierra Flooding land use hydraulic conductivity SPOT images Colima Mexico CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Aguadas de Calakmul, santuarios de vida silvestre

Rafael Reyna-Hurtado (2019)

Decir que el agua es fuente de vida es un lugar común, pero cierto. En la Reserva de la Biósfera Calakmul las aguadas son un elemento fundamental del paisaje, y especies como el jaguar, el pecarí de labios blancos o el tapir centroamericano recorren grandes distancias en su búsqueda, pues están dispersas y no son abundantes. Estas pequeñas lagunas superficiales son imprescindibles para la sobrevivencia de la fauna silvestre.

Article

Aguadas Aguas superficiales Vida silvestre Especies en peligro de extinción Hábitat (Ecología) Reserva de la Biosfera Calakmul (Campeche, México) CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO HIDROLOGÍA AGUAS SUPERFICIALES AGUAS SUPERFICIALES

Study of the properties of cosmic-rays using the ALICE-LHC detector

EMMA GONZALEZ HERNANDEZ (2021)

"ALICE is one of the four main experiments at the CERN Large Hadron Collider. The

location of ALICE detector allows the study the muonic component of cosmic-rays, since

it is located 52 meters underground with 28 meters of rock above it. The ALICE detector

is able to detect atmospheric muons from extensive air showers, making possible the study

of cosmic-rays physics. At this depth, only atmospheric muons with energies greater

than 16 GeV can reach the detection zone of ALICE. A study of cosmic charge ratio is

presented for events of atmospheric showers collected in 2015, 2016, 2017 and 2018 by the

ALICE experiment. The whole data sample corresponds to 62.5 days of data taking. The

analysis of the multiplicity distribution of atmospheric muons reconstructed by the Time

Projection Chamber (TPC) of ALICE is also presented. The rate of high muon multiplicity

events (number of muons >100) was estimated and compared with the predictions given

by QGSJET-II-04, SIBYLL and EPOS-LHC."

Doctoral thesis

Astrofísica nuclear Erupciones de rayos gamma Geomagnetismo Espectroscopía astronómica Rayos cósmicos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Subinché

Fernando Nuno Dias Marques Simoes (2021)

Registro de informacion general multidisciplinaria de cenotes de la peninsula de yucatan, proveniente de la base de datos de cenoteando.mx

Dataset

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA BIOLOGÍA Y QUÍMICA CIENCIAS SOCIALES

X-Pakay

Fernando Nuno Dias Marques Simoes (2021)

Registro de informacion general multidisciplinaria de cenotes de la peninsula de yucatan, proveniente de la base de datos de cenoteando.mx

Dataset

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA BIOLOGÍA Y QUÍMICA CIENCIAS SOCIALES

Popola

Fernando Nuno Dias Marques Simoes (2021)

Registro de informacion general multidisciplinaria de cenotes de la peninsula de yucatan, proveniente de la base de datos de cenoteando.mx

Dataset

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA BIOLOGÍA Y QUÍMICA CIENCIAS SOCIALES

Dzitox

Fernando Nuno Dias Marques Simoes (2021)

Registro de informacion general multidisciplinaria de cenotes de la peninsula de yucatan, proveniente de la base de datos de cenoteando.mx

Dataset

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA BIOLOGÍA Y QUÍMICA CIENCIAS SOCIALES