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Chinese Physics B 2019年第12期28卷 186-190页

作者： H Noverola-Gamas L M Gaggero-Sager O Oubram Instituto de Investigaciones en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos MorelosCuernavaca 62209Mexico division academica de ingeniería y arquitectura Universidad Juárez Autonoma de TabascoCunduacan 8660Mexico Centro de Investigación en ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico Facultad de Ciencias Químicas e ingeniería Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico

In the framework of the Thomas–Fermi(TF) approach, a model for the p-type double-δ-doped(DDD) system in Ga As is presented. This model, unlike other works in the literature, takes into account that the Poisson equation associated with the system is nonlinear. The electronic structure is calculated for heavy and light holes. The changes in the electronic structure result of the distance d between the doped layers are studied. In particular, the relative absorption coefficient as well as the relative refractive index change is calculated as a function of the incident photon energy for heavy holes. The effect of the interlayer distance exhibits, in the absorption coefficient, a red shift of the peak position and a decrease in amplitude when the distance increases. In addition, the relative refractive index change node has a red shift as well as the interlayer distance increases. The calculations show that the effect of the separation between layers has a greater influence on the linear terms. These results are very important for theoretical calculations and engineering of optical and electronic devices based in δ-doped Ga As.

关键词： double delta-doping p-type GaAs layers electronic structure Thomas–Fermi approach nonlinear optical properties

Nonlinear optical properties in n-type quadrupleδ-doped GaAs quantum wells

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Chinese Physics B 2022年第4期31卷 348-351页

作者： Humberto Noverola-Gamas Luis Manuel Gaggero-Sager Outmane Oubram division academica de ingenierıa y arquitectura Universidad Juarez Autonoma de TabascoCarretera Cunduacan-Jalpa de Mendez Km.1 Col.La EsmeraldaCunduacan8660Mexico Centro de Investigacion en ingenierıa y Ciencias Aplicadas Universidad Autonoma del Estado de MorelosAv.Universidad 1001 Col.ChamilpaCuernavaca62209Mexico Facultad de Ciencias Quımicas e ingenierıa Universidad Autonoma del Estado de MorelosAv.Universidad 1001 Col.ChamilpaCuernavaca62209Mexico

The effects of the interlayer distance on the nonlinear optical properties of n-type quadrupleδ-doped GaAs quantum well were theoretically ***,the absorption coefficient and the relative refraction index change were *** the effective mass approach and within the framework of the Thomas-Fermi theory,the Schrodinger equation was ***,the subband energy levels and their respective wave functions were *** variations in the nonlinear optical properties were determined by using the density matrix *** achieved results demonstrate that the interlayer distance causes optical red-shift on nonlinear optical ***,it can be deduced that the suitably chosen interlayer distance can be used to tune optical properties within the infrared spectrum region in optoelectronic devices such as far-infrared photo-detectors,high-speed electronic-optical modulators,and infrared lasers.

关键词： delta-doping n-type GaAs layers electronic structure non-linear optical properties

Fractal interpolation:a sequential approach

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Applied Mathematics(A Journal of Chinese Universities) 2021年第3期36卷 330-341页

作者： N.Vijender M.A.Navascus department of Mathematics Visvesvaraya National Institute of Technology NagpurNagpur 440010India departamento de Matem´atica Aplicada Escuela de Ingenier´ıa y ArquitecturaUniversidad de ZaragozaZaragoza 50018Spain

Fractal interpolation is a modern technique to fit and analyze scientific *** develop a new class of fractal interpolation functions which converge to a data generating(original)function for any choice of the scaling ***,our method offers an alternative to the existing fractal interpolation functions(FIFs).We construct a sequence of-FIFs using a suitable sequence of iterated function systems(IFSs).Without imposing any condition on the scaling vector,we establish constrained interpolation by using fractal *** particular,the constrained interpolation discussed herein includes a method to obtain fractal functions that preserve positivity inherent in the given *** existence of Cr--FIFs is *** identify suitable conditions on the associated scaling factors so that-FIFs preserve r-convexity in addition to the Cr-smoothness of original function.

关键词： fractal interpolation convergence sequence of operators constrained-FIFs fractal splines

From BIM model to 3D construction printing:A framework proposal

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Frontiers of Architectural Research 2024年第4期13卷 912-927页

作者： Rodrigo García-Alvarado Pedro Soza Ginnia Moroni Fernando Pedreros Martín Avendaño Pablo Banda Cristian Berríos depto.Diseño y Teoría de La arquitectura Universidad Del Bío-BíoConcepciónChile depto.arquitectura Universidad de ChileSantiagoChile Facultad de ingeniería Arquitectura y DiseñoUniversidad San SebastiánConcepciónChile Facultad de arquitectura Arte y DiseñoUniversidad Diego PortalesSantiagoChile

The growth of 3D construction printing needs appropriate integration into the planning and execution phases of building *** this aim,the Architecture,Engineering,and Construction sector(AEC)has been increasingly adopting building information modeling(BIM)systems to synchronize design and construction *** study proposes a technical workflow to manage 3D construction printing into BIM models,evaluating various procedures according to construction element *** on mature software platforms,the research details the data transfer process using a case study of a single-story *** case delves into design procedures for constructing walls of varied shapes,adjustments in width,joints,openings,textures,fillings,and the insertion of reinforcements and services while also discussing requirements of other building *** steps for managing design information and controlling printing machines are *** study’s outcome presents a comprehensive information flow,encompassing model segmentation,geometric data transfer,adjustments of details,and the generation of printing ***,it is offered a discussion that underlines the importance of a synergistic digital information flow that merges both design and execution phases,promoting construction efficiency and the embrace of innovative *** contribution of the paper focuses on technical design strategies for 3D construction printing,but also on suggesting an integrated process.

关键词： 3D construction printing Additive manufacturing Architectural design BIM

Fabrication of paper-based devices for in vitro tissue modeling

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Bio-design and Manufacturing 2020年第3期3卷 252-265页

作者： Hongbin Li Feng Cheng Juan A.Robledo-Lara Junlong Liao Zixuan Wang yu Shrike Zhang division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMA 02139USA College of Light Industry and Textile Qiqihar UniversityQiqihar 161000HeilongjiangPeople’s Republic of China departamento de ingeniería Mecatrónica y Eléctrica Escuela de Ingeniería y CienciasTecnológico de MonterreyCP 78211 San Luis PotosíSan Luis PotosíMexico

Paper devices have recently attracted considerable attention as a class of cost-effective cell culture substrates for various biomedical *** paper biomaterial can be used to partially mimic the in vivo cell microenvironments mainly due to its natural three-dimensional *** paper-based devices provide precise control over their structures as well as cell distributions,allowing recapitulation of certain interactions between the cells and the extracellular *** features have shown great potential for the development of normal and diseased human tissue *** this review,we discuss the fabrication of paper-based devices for in vitro tissue modeling,as well as the applications of these devices toward drug screening and personalized *** is believed that paper as a biomaterial will play an essential role in the field of tissue model engineering due to its unique performances,such as good biocompatibility,eco-friendliness,cost-effectiveness,and amenability to various biodesign and manufacturing needs.

关键词： Paper-based devices In vitro Tissue modeling Disease modeling Drug screening Personalized medicine

Comparative carbon emission assessments of recycled and natural aggregate concrete: Environmental influence of cement content

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Geoscience Frontiers 2021年第6期12卷 72-81页

作者： Marian Sab?u Dan V.Bompa Luis F.O.Silva department of Civil and Environmental Engineering Universidad de la Costa department of Civil and Environmental Engineering University of Surrey departamento de ingeniería Civil y arquitectura Universidad de Lima

This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural applications. The environmental influence of cement content, aggregate production, transportation, and waste landfilling is analysed by undertaking a life cycle assessment and considering a life cycle inventory largely specific for the region. To obtain a detailed insight into the optimum life cycle parameters, a sensitivity study is carried out in which supplementary cementitious materials, different values of natural-to-recycled aggregate content ratio and case-specific transportation distances were considered. The results show that carbon emissions were between 323 and 332 kg CO2e per cubic metre of cement only natural aggregate concrete. These values can be reduced by up to 17% by replacing 25% of the cement with fly ash. By contrast, carbon emissions can increase when natural coarse aggregates are replaced by recycled aggregates in proportions of 50% and 100%, and transportation is not included in analysis. However, the concrete with 50% recycled aggregate presented lower increase, only 0.3% and 3.4% for normal and high strength concrete, respectively. In some cases, the relative contribution of transportation to the total carbon emissions increased when cement was replaced by fly ash in proportions of 25%, and case-specific transportation distances were considered. In absolute values, the concrete mixes with 100% recycled aggregates and 25% fly ash had lower carbon emissions than concrete with cement and natural aggregates only. Higher environmental benefits can be obtained when the transportation distances of fly ash are relatively short(15–25 km) and the cement replacement by fly ash is equal or higher than 25%, considering that the mechanical properties are adequate for practical application. The observations from this paper show that recycled aggregate concrete with strength characteristics representative for s

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Comparative carbon emission assessments of recycled and natural aggregate concrete: Environmental influence of cement content

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Geoscience Frontiers 2021年第6期12卷 66-75页

作者： Marian Sabǎu Dan V.Bompa Luis F.O.Silva department of Civil and Environmental Engineering Universidad de la Costa080020 BarranquillaColombia department of Civil and Environmental Engineering University of SurreyGuildford GU27XHUK departamento de ingeniería Civil y arquitectura Universidad de LimaAvenida Javier Prado Este 4600Santiago de Surco 1503Peru

This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural *** environmental influence of cement content,aggregate production,transportation,and waste landfilling is analysed by undertaking a life cycle assessment and considering a life cycle inventory largely specific for the *** obtain a detailed insight into the optimum life cycle parameters,a sensitivity study is carried out in which supplementary cementitious materials,different values of natural-to-recycled aggregate content ratio and case-specific transportation distances were *** results show that carbon emissions were between 323 and 332 kgCO_(2)e per cubic metre of cement only natural aggregate *** values can be reduced by up to 17%by replacing 25%of the cement with fly *** contrast,carbon emissions can increase when natural coarse aggregates are replaced by recycled aggregates in proportions of 50%and 100%,and transportation is not included in ***,the concrete with 50%recycled aggregate presented lower increase,only 0.3%and 3.4%for normal and high strength concrete,*** some cases,the relative contribution of transportation to the total carbon emissions increased when cement was replaced by fly ash in proportions of 25%,and case-specific transportation distances were *** absolute values,the concrete mixes with 100%recycled aggregates and 25%fly ash had lower carbon emissions than concrete with cement and natural aggregates *** environmental benefits can be obtained when the transportation distances of fly ash are relatively short(15–25 km)and the cement replacement by fly ash is equal or higher than 25%,considering that the mechanical properties are adequate for practical *** observations from this paper show that recycled aggregate concrete with strength characteristics representative for structural members can have lowe

关键词： Life cycle assessment Recycled aggregate Natural aggregate Transportation distance OpenLCA

Major Existing Classification Matrices and Future Directions for Internet of Things

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Advances in Internet of Things 2017年第4期7卷 112-120页

作者： Kedir Mamo Basher Juan-Ivan Nieto-Hipolito Maria de Los Angeles Cosio Leon Mabel Vazquez-Briseno Juan de Dios Sánchez López Raymundo Buenrostro Mariscal Facultad de ingeniería Arquitectura y Dise&#241 o UABC Ensenada México

Classification method is a formula, logical description generalizing characteristics of objects of related area. Nowadays, billions of smart objects are immersed in the environment, sensing, interacting, and cooperating with each other to enable efficient services. When we think about IoT, classification is a major challenge particularly if our technology is international level applicable. So, this limitation needs clear and deep analysis of the existing classification matrixes and gives some future directions depending on the different researches in the area. The paper surveys the current state-of-art in the classification of IoT. First, we try to explain commonly existing classification matrixes;Second, cooperation of different methods defending on classification matrixes used. Then analyses challenges that IoT faced from classification angle and finally we give some direction for future IoT classification.

关键词： Internet of Things Classification of IoT IoT Overview Future of IoT Smart Objects

Environmental geochemistry:Introduction

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Geoscience Frontiers 2022年第1期13卷 374-375页

作者： Luis F.O.Silva Marcos L.S.Oliveira department of Civil and Environmental.Universidad de la Costa CUCCalle 58#55-66BarranquillaAtlánticoColombia departamento de ingeniería Civil y arquitectura Universidad de LimaAvenida Javier Prado Este 4600Santiago de Surco 1503Peru

Assessing the physical,geographic,chemical,and geological aspects are important to understand environmental impacts as well as health concerns in view of building a more sustainable planet with circular economies that would last for the foreseeable *** the recent years,the significance of incorporating ecosystem,anthropogenic activities,and climate has fortified from being an academic concern(e.g.,WEF,2011)into a broadly societal concern as the forecasted realities of environmental deterioration and global climate change come to pass.

关键词： geochemistry climate planet

Modelling of phosphorus accumulation in an aeroponic coriander crop

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International Journal of Agricultural and Biological Engineering 2022年第6期15卷 73-79页

作者： Alejandro Rincón Santamaría John E.Candelo-Becerra Fredy E.Hoyos Velasco Grupo de Investigación en desarrollos Tecnológicos y Ambientales-GIDTA Facultad de Ingeniería y ArquitecturaUniversidad Católica de Manizales170002 ManizalesColombia Grupo de Investigación en Microbiología y Biotecnología Agroindustrial-GIMIBAG Instituto de Investigación en Microbiología y Biotecnología AgroindustrialFacultad de Ciencias de la SaludUniversidad Católica de Manizales170002 ManizalesColombia department of Electrical Energy and Automation Faculty of MinesUniversidad Nacional de ColombiaSede MedellínMedellín 050041AntioquiaColombia

A model was developed for phosphorus(P)concentration over time in a closed aeroponic coriander *** addition,the setting and starting up of the soilless culture is described,and the measurements of electrical conductivity(EC),pH and concentration of major ions in the mixing tank are *** using mass balance principles,the dynamics of the nutrient concentration in the mixing tank and in the drainage solution are *** series of continuous stirred tank reactors are considered for the flow structure,using a power law relationship to represent the rate of nutrient removal,considering water volume *** concentration measurements were used for model fitting,and the resulting simulation is in good agreement with data.

关键词： aeroponic culture hydroponics soilless culture nutrient modelling Coriander sativum