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Gabor superlens with variable focus

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Chinese Optics Letters 2020年第12期18卷 68-72页

作者： A.Garza-Rivera J.E.Gomez-Correa F.J.Renero-Carrillo J.P.Trevino V.Coello INAOE Departtunento de OpticaTonantzintlaPuebla72840Mexico Catedras Conacyt-cicese Unidad MonterwyPUT ApodacaNuevo Leon66629Mexico Tecnoldgico de Monterrey Campus PueblaDepartainento de Bioingenicrfay CicnciasPueblaPuebla72453Mexico cicese Unidad MonterreyPUT ApodacaNuevo Leon66629Alexico

In this Letter,a Gabor superlens with variable focus is presen *** configuration uses tunable liquid lenses in the third microlens array of the Gabor *** applying voltage,the radius of curvature of the microtunable doublet arrays changes,and the Gabor conditions are fulfilled at different focal *** a consequence,the magnification of the image at the focal planes changes,and a zoom effect is *** marginal depth plane for this system goes from 0.86 to 0.89 *** optical simulation,calculations,and results of the simulated optical system performance are presented.

关键词： Gabor superlens micro-tunable lens multi-aperture optics geometric optical design

NORRRM: A Free Software to Calculate the CIPW Norm

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Open Journal of Geology 2016年第1期6卷 30-38页

作者： Reneé González-Guzmán Posgrado en Ciencias de la Tierra CICESE Ensenada Baja California México

This work gives an introduction to the R package NORRRM whose main purpose is to calculate the CIPW Norm. Although there are many softwares and spreadsheets available to estimate the standard mineral assemblages in igneous rocks, this package has the following advantages: a) it has the ability to be run on any operating computer systems (BSD, GNU/Linux, Mac OS X®, Windows®);b) an input argument allows choose different procedures to set the Fe-oxidation ratio;c) the options to use whole-rock major as well as minor oxides and trace elements in the computation;d) the output data yields highly consistent results achieving absolute match between the sum of the input weights of oxides recalculated on an anhydrous basis and the sum of the weights of estimated normative minerals and;e) the functions are written in R language and released under terms that guarantee users the freedom to study, adapt, modify, and distribute the software.

关键词： Igneous Petrology CIPW Norm Fe Oxidation Ratio Free Software

Correcting the Gutenberg–Richter b-value for effects of rounding and noise

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Earthquake Science 2015年第2期28卷 129-134页

作者： V.H.Márquez-Ramírez F.A.Nava F.R.Zúiga UNAM Campus Querétaro México Centro de GeocienciasBlvd.Juriquilla No 3001 76230 México Querétaro México Seismology Department CICESE Carretera Ensenada-Tijuana No 3918 Zona Playitas 22860 Ensenada BC México

The effects of magnitude rounding and of the presence of noise in the rounded magnitudes on the estimation of the Gutenberg-Richter b-value are explored, and the ways to correct for these effects are proposed. For typical values, b = 1 and rounding interval △M = 0.1, the rounding error is approximately -10^-3 and it can be corrected to a negligible approximately -10^-5. For the same typical values, the effect of noise can be larger, depending on the characteristics of the noise distribution; for normally distributed noise with standard deviation σ = 0.1, the correct b-value may be underestimated by a factor - 0.97.

关键词： b-Value Noise Magnitude

Plasmonic metasurface Luneburg lens

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Photonics Research 2019年第10期7卷 1112-1118页

作者： C.E.GARCIA-ORTIZ R.CORTES J.E.GOMEZ-CORREA E.PISANO J.FIUTOWSKI D.A.GARCIA-ORTIZ V.RUIZ-CORTES H.-G.RUBAHN V.COELLO cicese Unidad MonterreyAlianza Centro 504PIITApodacaNL 66629Mexico Catedras CONACYT-Centro de Investigaciones enoptica Alianza Centro 504PIITApodacaNL 66629Mexico Mads Clausen Institute University of Southern DenmarkNanoSYDAlsion 2 DK6400S?nderborgDenmark CICFIM-UANL Av Universidad S/NSan Nicolas de los GarzaNL 66450Mexico Departamento deoptica CICESEEnsenadaBC 22860Mexico

We present a new design of a plasmonic Luneburg lens made from a gradient-index metasurface that was constructed with an array of nanometer-sized holes in a dielectric thin film. The fabricated structure consists of a planar lens with a diameter of 8.7 μm composed of a rectangular array of holes with a periodicity of 300 nm. The experimental characterization includes leakage-radiation microscopy imaging in the direction and frequency space. The former allows for characterization of the point spread function and phase distribution,whereas the latter grants access to qualitative measurements of the effective mode indices inside the plasmonic lens. The experimental results presented here are in good agreement with the expected average performance predicted by the numerical calculations. Nevertheless, the robustness of the characterization techniques presented here is also exploited to determine deviations from the design parameters.

关键词： space. film. characterization

Ellipsometric Study of SiOx Thin Films by Thermal Evaporation

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Open Journal of Inorganic Chemistry 2016年第3期6卷 175-182页

作者： David Salazar Roberto Soto-Molina Eder German Lizarraga-Medina Marco Antonio Felix Nicola Radnev Heriberto Márquez Departamento de óptica CICESE Ensenada México Instituto de Ingeniería Universidad Autónoma de Baja California Mexicali México

This paper presents a study of amorphous SiOx thin films by means of Variable Angle Spectroscopic Ellipsometry (VASE) technique. Tauc Lorentz, Lorentz and Cauchy models have been used to obtain physical thickness and complex refractive index (n and k) from experimental data. In order to obtain a wide range to x stoichiometry values, the films were prepared by vacuum thermal evaporation of SiO on glass substrates, under different and controlled deposition conditions.

关键词： Ellipsometry Refraction Index SiOx Thin Films

Computational Method for Extracting and Modeling Periodicities in Time Series

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Open Journal of Statistics 2015年第6期5卷 604-617页

作者： Eduardo González-Rodríguez Héctor Villalobos Víctor Manuel Gomez-Munoz Alejandro Ramos-Rodríguez Oceanografia Tropical CICESE Unidad La PazLa PazMexico Instituto Politecnico Nacional-CICIMAR La PazB.C.SMexico

Periodicity is common in natural processes, however, extraction tools are typically difficult and cumbersome to use. Here we report a computational method developed in MATLAB through a function called Periods with the aim to find the main harmonic components of time series data. This function is designed to obtain the period, amplitude and lag phase of the main harmonic components in a time series (Periods and lag phase components can be related to climate, social or economic events). It is based on methods of periodic regression with cyclic descent and includes statistical significance testing. The proposed method is very easy to use. Furthermore, it does not require full understanding of time series theory, nor require many inputs from the user. However, it is sufficiently flexible to undertake more complex tasks such as forecasting. Additionally, based on previous knowledge, specific periods can be included or excluded easily. The output results are organized into two groups. One contains the parameters of the adjusted model and their F statistics. The other consists of the harmonic parameters that best fit the original series according to their importance and the summarized statistics of the comparisons between successive models in the cyclic descent process. Periods is tested with both, simulated and actual sunspot and Multivariate ENSO Index data to show its performance and accuracy.

关键词： Time Series Cyclic Descent Harmonic Periodicity Forecasting Sunspot Multivariate ENSO Index

Presence of Sargassum horneri at Todos Santos Bay, Baja California, Mexico: Its Effects on the Local Macroalgae Community

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American Journal of Plant Sciences 2015年第17期6卷 2693-2707页

作者： Giuliana I. Cruz-Trejo Silvia E. Ibarra-Obando Luis E. Aguilar-Rosas Miriam Poumian-Tapia Elena Solana-Arellano Marine Ecology Department CICESE Ensenada México Ocean Resources Department CINVESTAV-IPN Mérida México Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja California Ensenada México

To describe the annual cycle of Sargassum horneri in Mexican waters, we selected two sites differing in their degree of wave exposure and sediment type: Rincón de Ballenas (RB), and Rancho Packard (RP). From June 2009 to April 2010 we followed the seasonal changes in S. horneri density and biomass along two intertidal transects per site. The effects of this non-indigenous species on the local macroalgae community were assessed by comparing their species composition, density, biomass, species richness, and diversity index in quadrats with and without S. horneri. There were significant differences in S. horneri density and biomass between sites (P < 0.001). At RB the invasive alga density average was 2 ± 0.94 individual m-2, with a mean biomass of 4 ± 0.95 g DW m-2. At RP, S. horneri density average was 10 ± 0.96 individual m-2, and mean biomass of 102 ± 0.97 g DW m-2. At RB, the invasive alga promoted a significant reduction in the four selected structural variables, and the corticated macrophytes and the foliose functional forms were severely reduced. At RP, there were only marginally significant effects (P = 0.06) of S. horneri presence on the local macroalgae community, and higher density, biomass, and diversity values were found when S. horneri was present. Most of the functional forms were found, even if the invasive alga was present. At both locations, the highest biomass corresponded to the articulated calcareous functional form. These contrasting results could be due to the fact that the native macroalgae community has already been altered by the early invasion of S. muticum, with the most resilient species and functional forms remaining in place. One of the most important changes we noticed is the severe reduction of the canopy forming species at both sites.

关键词： Annual Cycle Community Structure Diversity Index Functional Forms Invasive Alga Species Richness

A Brief Tour on Exotic Control Objectives in Robotics

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Journal of Mechanics Engineering and Automation 2018年第2期8卷 53-59页

作者： Rafael Kelly Carmen Monroy DET-DFA Division de Fisica Aplicada CICESE Carretera Ensenada-Tijuana No. 3918 Zona Playitas Ensenada B.C. 22860 Mexico ISEP-Sistema Educativo Estatal Zona 01 Ensenada B.C. 22800 Mexico

Formulation of control objectives is a key issue in automatic control systems design. Although at first sight the desired goal （control objective） of a control system seems to be a trivial and obvious matter, for effectiveness of some high level robotic tasks, unusual exotic control objectives may be required. This paper presents a review of some exotic control objectives useful in robotics, such as velocity field control objective and range control objective. The paper also proposes a novel confinement control objective. The usefulness of these exotic control objectives may appear in safe robot-human interaction and self-protection of robots against collisions.

关键词： Control objective robot robot-human confinement range velocity field TEFDA (total energy function with damping assignment) exotic.

Thermal preference, tolerance and temperature-dependent respiration in the California sea hare <i>Aplysia californica</i>

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Agricultural Sciences 2013年第6期4卷 46-52页

作者： Ana Denisse Re Fernando Díaz Alfredo Salas-Garza Marco Gonzalez Victor Cordero Clara E. Galindo-Sanchez Edna Sanchez-Castrejon Adolfo Sánchez Zamora Alexei Licea-Navarro Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja California Ensenada Baja California México Laboratorio de Biología Celular y Molecular Departamento de Biotecnología Marina Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE) Ensenada Baja California México Laboratorio de Ecofisiología de Organismos Acuáticos Departamento de Biotecnología Marina Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE) Ensenada Baja California México Laboratorio de Ecofisiología de Organismos Acuáticos Departamento de Biotecnología Marina Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE) Ensenada Baja California México Laboratorio de Genómica Funcional Departamento de Biotecnología Marina Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE) Ensenada Baja California México Unidad Multidisciplinaria de Docencia e Investigación Facultad de Ciencias Universidad Autónoma de México Sisal México

The thermoregulatory behavior of sea hare Aplysia californica was determined in a horizontal thermal gradient;with a preferred temperature (PT) of 18.3°C for the day cycle and 20.8°C for the night cycle. The displacement velocity demonstrated an initial rate of 30 cm·hˉ1 and gradually the velocity diminished to 18 cm·hˉ1 with several fluctuations mainly at 02:00 am. Critical Temperature Maxima (CTMax refers to the temperature point where at least 50% of the experimental group have a loss of attachment) was measured at three acclimation temperatures (16°C, 19°C and 22°C). At the lowest acclimation temperature (16°C), 50% of the experimental group had an attachment loss at CTMax 32.7°C, and in a higher acclimation temperature (22°C) CTMax was 36.2°C. The Oxygen Consumption Rate (OCR) was closely correlated to acclimation temperature, and at 16°C and 19°C sea hare had a relatively stable metabolic rate, with OCR increasing to 9 mg O2 hˉ1·kgˉ1 w.w. in a higher acclimation temperature.

关键词： Thermoregulatory Behavior CTMax Oxygen Consumption Aplysia californica