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Analysis and parameter extraction of memristive structures based on Strukov's non-linear model

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Journal of Semiconductors 2018年第12期39卷 106-113页

作者： A.Avila Garcia L.Ortega Reyes Centro de Investigacion y de Estudios Avanzados del Instituto Polit6cnico Nacional Departamento de Ingenieria ElectricaSeccion de Electronica del Estado SolidoMexico 07360Mexico

Diverse models have been proposed for explaining the electrical performance of memristive devices. In principle, the behavior of internal variables associated to each one could be extracted from experimental results. In a former work, thermally grown TiOmemristive structures were built and characterized to obtain the constitutive relationship(magnetic flux versus charge). The aim of this work is to continue that analysis by determining the microscopic parameters within the frame of a simple model. We use the already obtained memristance dependence of time and the basic expressions from the non-linear model proposed by Strukov et al. to compute the state-variable,the mobility of the doping species, the speed of the boundary between the doped and the undoped regions, the voltages and the electric fields on the distinct regions. The power dissipation and its time evolution are also presented. Moreover, a quite different window function from those formerly proposed, which was estimated from experimental data, is also determined. This information provides a straightforward picture of the ionic transport during one cycle of a square voltage waveform within the framework of this simple model. Finally, a quality factor is proposed as the key parameter for actual memristors viewed under the same model.

关键词： memristors parameter extraction non-linear model experimental window function

Recent Advances on Early-Stage Fire-Warning Systems: Mechanism, Performance, and Perspective

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Nano-Micro Letters 2022年第12期14卷 106-136页

作者： Xiaolu Li Antonio Vazquez-Lopez Jose Sanchez del Rio Saez de-yi Wang IMdeA Materials Institute C/Eric Kandel228906 GetafeMadridSpain E.T.S.de Ingenieros de Caminos Universidad Politecnica de MadridCalle Profesor Aranguren 328040 MadridSpain departamento de Ingenieria Electrica Electronica Automatica y Fisica AplicadaETSIDIUniversidad Politecnica de MadridRonda de Valencia 328012 MadridSpain

Early-stage fire-warning systems(EFWSs)have attracted significant attention owing to their superiority in detecting fire situations occurring in the pre-combustion *** progress on EFWSs has been achieved recently,and they have presented a considerable possibility for more evacuation time to control constant unintentional fire hazards in our daily *** review mainly makes a comprehensive summary of the current EFWSs,including the working mechanisms and their *** to the different working mechanisms,fire alarms can be classified into graphene oxide-based fire alarms,semiconductor-based fire alarms,thermoelectric-based fire alarms,and fire alarms on other working ***,the challenge and prospect for EFWSs are briefly provided by comparing the art of state of fire *** work can propose a more comprehensive understanding of EFWSs and a guideline for the cutting-edge development direction of EFWSs for readers.

关键词： Smart thermosensitive fire sensors Working mechanism Response time Signal conversion

Time-expanded phase-sensitive optical time-domain reflectometry

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Light(Science & Applications) 2021年第3期10卷 443-454页

作者： Miguel Soriano-Amat Hugo F.Martins Vicente Duran Luis Costa Sonia Martin-Lopez Miguel Gonzalez-Herraez Maria R.Fernandez-Ruiz departamento de electronica Universidad de AlcalaEscuela Politecnica Superior28805 MadridSpain Instituto deóptica"Daza de Valdes" IO-CSICC/Serrano 12128006 MadridSpain GROC-UJI Institute of New Imaging TechnologiesUniversity Jaume112071 CastellonSpain

Phase-sensitive optical time-domain reflectometry(CDOTDR)is a well-established technique that provides spatiotemporal measurements of an environmental variable in real *** unique capability is being leveraged in an everincreasing number of applications,from energy transportation or civil security to *** date,a wide number of different approaches have been implemented,providing a plethora of options in terms of performance(resolution,acquisition bandwidth,sensitivity or range).However,to achieve high spatial resolutions,detection bandwidths in the GHz range are typically required,substantially increasing the system cost and ***,we present a novel OOTDR approach that allows a customized time expansion of the received optical ***,the presented technique reaches cm-scale spatial resolutions over t km while requiring a remarkably low detection bandwidth in the MHz *** approach relies on the use of dual-comb spectrometry to interrogate the fibre and sample the backscattered *** phase-spectral coding is applied to the employed combs to maximize the signal-to-noise ratio of the sensing scheme.A comparison of the proposed method with alternative approaches aimed at similar operation features is provided,along with a thorough analysis of the new *** results demonstrate a radically novel high-resolution OOTDR scheme,which could promote new applications in metrology,borehole monitoring or aerospace.

关键词： optical phase expanded

Verification Protocols for the Lightning Protection of a Large Scale Scientific Instrument in Harsh Environments: A Case Study

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Journal of Power and Energy Engineering 2021年第6期9卷 12-28页

作者： Oibar Martinez Silvia Ronda Clara Oliver Patricia Marquez Jose Miguel Miranda departamento de Estructura de la Materia Fisica Termica y Electronica Facultad de Fisicas Universidad Complutense de Madrid Madrid Spain

This paper is devoted to the study of the most suitable protocols needed to verify the lightning protection and ground resistance quality in a large-scale scientific facility located on a site with high risk of lightning strikes. We illustrate this work by reviewing a case study: the largest telescopes of the Northern Hemisphere Cherenkov Telescope Array, CTA-N. This array hosts sensitive and high-speed optoelectronics instrumentation and sits on a clear, free from obstacle terrain at around 2400 m above sea level. The site offers a top-quality sky but also features challenging conditions for a lightning protection system: the terrain is volcanic and has electrical resistivities well above 1 kOhm·m. In addition, the environment often exhibits humidities well below 5%, and strong winds pose challenging conditions. On the other hand, the high complexity of a Cherenkov telescope structure does not allow a straightforwardyle="font-family:Verdana;"> application of lightning protection standards. We describe here how the risk assessment of direct strike impacts was made and how contact voltages and ground system were both tested. Finite Element Simulation (COMSOL Multiphysics) has been used to estimate the current flowing through the parts of the earthing system designed for the telescopes in the case of a direct strike impact. This work is intended to provide assistance to scientists and managers involved in the construction of scientific installations, particularly those in charge of defining verifiable reliability and safety requirements for lightning protection.

关键词： Lightning Protection Earth Resistance FEM COMSOL

Control of disability glare by means of electrochromic filtering glasses:A pilot study

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Journal of Innovative Optical Health Sciences 2017年第1期10卷 11-20页

作者： Rosa Maria Coco-Martín Ruben Cuadrado-Asensio Ceesar Vega-Colado Ricardo Vergaz Jose M.Sanchez-Pena Ana Viñuales Sergi Peris Pau Artús M.Begona Coco-Martín IOBA Universidad de ValladolidValladolidSpain GDAF-UC3M Grupo de Displays y Aplicaciones Fotonicas Department de Tecnologia Electronica Universidad Carlos III de MadridSpain IK4-CIdeTEC Parque Tecnologico de San Sebastian GuipuzcoaSpain Indo Optical Group Departamento I+D SantCugat del Valles BarcelonaSpain GIDFyS European University Miguel de Cervantes(UEMC)Department of HealthSciencesSpain

Purpose:To evaluate the potential clinical usability of a new prototype of ophthalmic blue light filters developed by using electrochromic technology in pseudophakic patients complaining of ***:A prototype of electrochromic device was developed,with a specific frame that enclosed an electronic driver that allowed personalizing its function for each patient.A pro-spective,observational case series study was performed to test *** patients who had un-dergone cataract surgery with clear intraocular lenses and complaining of glare were included in the *** outcome measures were the results obtained in the satisfaction questionnaire that was delivered to ***,visual acuity,contrast sensitivity,and reading ability data were evaluated with and without the prototype under diferent lighting conditions and different modes of the prototype after a complete month of *** transmittance was also ***:Visual acuity,contrast sensitivity and reading function did not change significantly with prototype *** main activity for which the prototype was used was *** one patient found that the dimming level was *** patients reported variable discomfort when passing tunnels,not sufficiently clear indoors,or put on and remove *** lenses slightly decreased their transmittance at the end of the ***:Glasses based on elect rochromic technology may be acceptable for outdoor/indoor use and for distance-near *** studies with larger samples must be conducted to confirm the clinical usability of these glasses.

关键词： Optical filters electro-optical devices technical visual aids electronic control.

Velocity Monitoring of Molten Steel in a Continuous Casting Mold Using Three Submerged Entry Nozzle designs

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Modeling and Numerical Simulation of Material Science 2016年第4期6卷 59-68页

作者： Raul Miranda Miguel A. Barron Carlos A. Hernandez departamento de electronica Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

The horizontal and vertical velocity components of molten steel in a slab continuous casting mold produced by three different two-port Submerged Entry Nozzle (SEN) designs are monitored and compared using Computational Fluid Dynamics (CFD) simulations. These two ports designs correspond to a conventional cylindrical SEN, a plate SEN and an anchor-shaped SEN. Four monitoring points at the molten steel in the centered vertical plane were selected to track the horizontal and the vertical component of the velocity vector. Two of them are located near the free surface and the remaining two are located in the vicinity of the SEN discharge nozzles. Some statistical values of the time series of above the velocity components are analyzed and correlated with the Kelvin-Helmholtz instability and the Karman vortex streets, which cause mold powder entrapment in the molten steel.

关键词： Computational Fluid Dynamics Continuous Casting Molten Steel Mold Powder Entrapment Submerged Entry Nozzle Velocity Monitoring

Anchor-Shaped design of a Submerged Entry Nozzle for the Continuous Casting of Steel

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Open Journal of Applied Sciences 2016年第9期6卷 593-600页

作者： Carlos A. Hernandez Miguel A. Barron Raul Miranda departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico departamento de electronica Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

An anchor-shaped geometrical design for a Submerged Entry Nozzle for the slab continuous casting of steel is presented in this work. To evaluate its performance, transient 3D multiphase numerical simulations were carried out using the Computational Fluid Dynamics technique. The performance of the proposed nozzle is numerically compared with that of a conventional cylindrical nozzle. Computer results show that the chance of formation of Karman’s vortexes and powder entrapment becomes small for the anchor-shaped SEN.

关键词： Anchor-Shaped SEN Computational Fluid Dynamics Continuous Casting Numerical Simulations Slab Casting Submerged Entry Nozzle

A Review on Genetically Modified Plants designed to Phytoremediate Polluted Soils： Biochemical Responses and International Regulation

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Pedosphere 2018年第5期28卷 697-712页

作者： Edgar VAZQUEZ-NUNEZ Julian M. PENA-CASTRO Fabian FERNANdeZ-LUQUENO Eduardo CEJUDO Maria G. de la ROSA-ALVAREZ Maria C. GARCIA-CASTANED departamento de Ingenierias Quimica Electronica y Biomedica Division de Ciencias e Ingenierlas Universidad de Guanajuato (UG) Campus Leon Loma del Bosque 103 Leon Gto. 37150 (Mexico) Laboratorio de Biotecnologla Vegetal Instituto de Biotecnologia Universidad del Papaloapan Tuxtepec Oaxaca 68333 (Mexico) programa en Sustentabilidad de los Recursos Naturales y Eneryla Cinvestav Saltillo Industria Metalurgica 1062 Parque Industrial Saltillo-Ramos-Arizpe Ramos Arizpe Coahuila 25900 (Mexico) CONACyT Unidad de Ciencias del Agua (UCIA) Centro de Investigacion Cientifica de Yucatan A.C. Cancdn Quintana Roo 77500 (Mexico) Center for the Environmental Implications of Nanotechnology University of California at Los Angeles- University of Texas at El Paso 500 W University Ave El Paso 79968 (USA) CONACyT Universidad de Guanajuato Loma del Bosque 103 Leon Guanajuato 37150 (Mexico)

In recent years,there has been an increasing interest in finding sustainable strategies for the efficient removal of contaminants from *** objective of this review is to examine the biochemical principles of specific genetic modifications in plants,their applications in the field for specific contaminants as phytotechnologies,and their international *** addition,the review presents some biological aspects of rhizosphere-related phenomena,the interactions of organic and inorganic pollutants with plants,and the performance of the phytotechnologies across the *** the last few decades,at least eight genera of genetically modified plants(GMPs)have been tested and used for soil remediation with outstanding ***,Nicotiana,and Oryza are the plant genera most widely *** plant genes such as metal transporters,chelators,metallothioneins,phytochelatins,and oxygenases have been transferred to plants to improve the elimination of contaminants in *** discuss some important aspects of gene manipulation and its application for removal of diverse contaminants.A key challenge faced by phytotechnologies is the final disposal of the generated biomass,from a safety *** argue that the commercial success of phytotechnologies depends on the generation of valuable biomass on contaminated land and its use for bioenergy *** use of such technologies would promote a broader understanding of the importance of plants,especially GMPs,in the environment and their contribution to environmental sustainability.

关键词： bioenergy contaminants gene manipulation phytotechnology plant-microbe interaction regulatory policy soil pollu-tion soil remediation

The Fundamental Mechanisms of the Absorption Process of Si During Rapid Thermal Process

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材料科学与工程（中英文B版） 2012年第10期2卷 517-522页

作者： Ivaldo Torres Cristobal Voz Ramon Alcubilla Grupo LOGOS Departamento EETS Facultad de Ingenierlas y Arquitecturas Universidad de Pamplona Km 1 Via a Bucaramanga Pamplona Norte de Santander Colombia departament d'Engenyeria electronica Universitat Politecnica de Catalunya C/ Gran Capita s/n Campus Nord 08074 Barcelona Espana