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Light(Science & Applications) 2020年第1期9卷 1398-1409页

作者： Jerome Lapointe Jean-Philippe Berube Yannick Ledemi Albert Dupont Vincent Fortin Younes Messaddeq real vallee Centre d’Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalG1V 0A6 QuebecQCCanada

Multiphoton absorption via ultrafast laser focusing is the only technology that allows a three-dimensional structural modification of transparent ***,the magnitude of the refractive index change is rather limited,preventing the technology from being a tool of choice for the manufacture of compact photonic integrated *** propose to address this issue by employing a femtosecond-laser-induced electronic band-gap shift(FLIBGS),which has an exponential impact on the refractive index change for propagating wavelengths approaching the material electronic resonance,as predicted by the Kramers–Kronig *** by theoretical calculations,based on a modified Sellmeier equation,the Tauc law,and waveguide bend loss calculations,we experimentally show that several applications could take advantage of this ***,we demonstrate waveguide bends down to a submillimeter radius,which is of great interest for higher-density integration of fs-laser-written quantum and photonic *** also demonstrate that the refractive index contrast can be switched from negative to positive,allowing direct waveguide inscription in ***,the effect of the FLIBGS can compensate for the fs-laser-induced negative refractive index change,resulting in a zero refractive index change at specific wavelengths,paving the way for new invisibility applications.

关键词： waveguide millimeter refractive

Watt-level and spectrally flat mid-infrared supercontinuum in fluoroindate fibers

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Photonics Research 2018年第6期6卷 609-613页

作者： FRANCIS THEBERGE NANCY BERUBE SAMUEL POULAIN SOLENN COXIC LOUIS-RAFAEL ROBICHAUD MARTIN BERNIER real vallee Defence R&D Canada Valcartier Centre Quebec G3J1X5 Canada Le Verre Fluore Campus KerLann F-35170 Bruz Brittany France Center for Optics Photonics and Lasers (COPL) Universite Laval Quebec G1V0A6 Canada

We report on infrared supercontinuum （SC） generation in step-index fluoroindate-based fiber by using an all-fiber laser source. In comparison to widely used ZBLAN fibers for high-power mid-infrared （MIR） SC generation, fluoroindate fibers have multiphoton absorption edges at significandy longer wavelengths and can sustain similar intensities. Recent developments highlighted in the present study allowed the production of fluoroindate fibers with MIR background loss of 2 dB/km, which is similar to or even better than ZBLAN fibers. By using an all-fiber picosecond laser source based on an erbium amplifier followed by a thulium power amplifier, we demonstrate the generation of 1.0 W infrared SC spanning over 2.25 octaves from 1 μm to 5 μm. The generated MIR SC also exhibits high spectral flatness with a 6 dB spectral bandwidth from 1.91 μm to 4.77 μm and an average power two orders of magnitude greater than in previous demonstrations with a similar spectral distribution.

关键词： Fiber optics infrared Nonlinear optics fibers Supercontinuum generation

Indoor localization for pedestrians with real-time capability using multi-sensor smartphones

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Geo-Spatial Information Science 2019年第2期22卷 73-88,I0001页

作者： Catia real Ehrlich Jörg Blankenbach Geodetic Institute and Chair for Computing in Civil Engineering&Geo Information Systems RWTH Aachen UniversityAachenGermany

The localization of persons or objects usually refers to a position determined in a spatial reference ***,this is usually accomplished with Global Navigation Satellite Systems(GNSS).However,the automatic positioning of people in GNSS-free environments,especially inside of buildings(indoors)poses a huge ***,satellite signals are attenuated,shielded or reflected by building components(*** or ceilings).For selected applications,the automatic indoor positioning is possible based on different technologies(***,RFID,or UWB).However,a standard solution is still not *** indoor positioning systems are only suitable for specific applications or are deployed under certain conditions,*** infrastructures or sensor ***,as popular cost-effective multi-sensor systems,is a promising indoor localization platform for the mass-market and is increasingly coming into ***’s devices are equipped with a variety of sensors that can be used for indoor *** this contribution,an approach to smartphone-based pedestrian indoor localization is *** novelty of this approach refers to a holistic,real-time pedestrian localization inside of buildings based on multisensor smartphones and easy-to-install local positioning *** this purpose,the barometric altitude is estimated in order to derive the floor on which the user is *** 2D position is determined subsequently using the principle of pedestrian dead reckoning based on user's movements extracted from the smartphone *** order to minimize the strong error accumulation in the localization caused by various sensor errors,additional information is integrated into the position *** building model is used to identify permissible(***,passageways)and impermissible(***)building areas for the *** technologies contributing to higher precision and robustness are also *** the fusion of diffe

关键词： Indoor positioning MEMS recursive Bayesian estimation particle filter sensor fusion Bluetooth beacons WLAN fingerprinting magnetic anomalies

Assessment of skeletal muscle alterations and circulating myokines in metabolic dysfunction-associated steatotic liver disease:A crosssectional study

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World Journal of Gastroenterology 2025年第7期31卷 63-73页

作者： Yolanda real Martinez Carlos Ernesto Fernandez-Garcia Esther Fuertes-Yebra Mario Calvo Soto Angela Berlana Vicente Barrios Maria Caldas Leticia Gonzalez Moreno Luisa Garcia-Buey Begoña Molina Baena Miguel Sampedro-Nuñez Maria J Beceiro C García-Monzón Águeda González-Rodríguez Servicio Aparato Digestivo Hospital Universitario La PrincesaInstituto de Investigación Sanitaria La PrincesaUniversidad Autónoma de MadridMadrid 28006Spain Unidad de Investigación Hospital Universitario Santa CristinaInstituto de Investigación Sanitaria La PrincesaMadrid 28009Spain Department of Endocrinology Department of PediatricsHospital Infantil Universitario Niño JesúsInstituto de Investigación La PrincesaMadrid 28009Spain Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición Instituto de Salud Carlos IIIMadrid 28029Spain Servicio de Endocrinología y Nutrición Hospital Universitario La PrincesaInstituto de Investigación Sanitaria La PrincesaUniversidad Autónoma de MadridMadrid 28006Spain Instituto de Investigaciones Biomédicas Sols-Morreale(IIBM) CSIC-UAMMadrid 28029Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas Madrid 28029Spain

BACKGROUND Skeletal muscle alterations(SMAs)are being increasingly recognized in patients with metabolic dysfunctionassociated steatotic liver disease(MASLD)and appear to be associated with deleterious outcomes in these ***,their actual prevalence and pathophysiology remain to be *** To determine the prevalence of SMAs and to assess the significance of circulating myokines as biomarkers in patients with *** Skeletal muscle strength and muscle mass were measured in a cross-sectional study in a cohort of 62 patients fulfilling MASLD criteria,recruited from the outpatient clinics of a tertiary level *** degree of fibrosis and liver steatosis was studied using abdominal ultrasound and transitional *** and metabolic characteristics as well as serum levels of different myokines were also determined in the MASLD *** analysis was performed comparing results according to liver fibrosis and *** No significant differences were found in both skeletal muscle strength and skeletal muscle mass in patients with MASLD between different stages of liver ***,serum levels of fibroblast growth factor-21(FGF21)were significantly higher in patients with MASLD with advanced hepatic fibrosis(F3-F4)than in those with lower fibrosis stages(F0-F2)(197.49±198.27 pg/mL vs 95.62±83.67 pg/mL;P=0.049).In addition,patients with MASLD with severe hepatosteatosis(S3)exhibited significantly higher serum levels of irisin(1116.87±1161.86 pg/mL)than those with lower grades(S1-S2)(385.21±375.98 pg/mL;P=0.001).CONCLUSION SMAs were uncommon in the patients with MASLD *** serum levels of irisin and FGF21 were detected in patients with advanced liver steatosis and fibrosis,respectively,with potential implications as biomarkers.

关键词： Skeletal muscle alterations Myokines Metabolic dysfunction-associated steatotic liver disease Liver fibrosis Hepatosteatosis

Changes in potential mammal diversity in national parks and their implications for conservation

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Current Zoology 2018年第6期64卷 671-679页

作者： Alba ESTRADA A.Marcia BARBOSA Raimundo real Biogeography Diversity and Conservation LabDepartment of Animal BiologyUniversidad de MalagaSpain Research Unit of Biodiversity (UMIB UO-CSIC-PA)Oviedo Univ.-Campus MieresSpain CIBIO/InBIO-University of Evora Portugal

Observed species richness (OSR)is a widely used and well-studied biodiversity ***, non-observed species in favorable ecosystems are also *** metrics that include observed and potential species were recently defined:potential biodiversity (hereafter potential species richness--PSR)and geometric mean of favorabilities (GMF).We used these metrics to evaluate the national park network of mainland Spain at two time periods (2002 and 2015),using terrestrial mammals on a UTM 100-km^2 *** and GMF are based on the favorability function, a species distribution model that assesses how favorable an area is for the presence of a species, over and above its prevalence in the study *** each park and for the whole network,we calculated the mean and sum of OSR,PSR,and GMF in each time period,as well as changes between *** and PSR were higher inside than outside the park network in both time periods. Thus,although the network covers a very small proportion of the country,it performs well for the representation of mammal species and their favorable ***,mean PSR was lower in 2015 than in 2002 inside the national park network,whereas the opposite was the case outside the *** Parks generally not only concentrated highly favorable areas for mammals, but they also showed less favorable areas in 2015 compared to 2002,although the reduction was moderate to *** is a result to consider for future analyses because if the tendency increases, it may have consequences for the conservation of mammals and for the adequacy of the national park network.

关键词： conservation planning dark diversity environmental favorability potential biodiversity protected areas

Analysis of three-dimensional vortexes below the free surface in a continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 397-406页

作者： Cesar A.real-Ramirez Jesus I.Gonzalez-Trejo Universidad Autonoma Metropolitana-Azcapotzalco.San Pablo 180 02200Mexico CityMexico

To study fluctuations of the free surface of liquid steel in the mold,two different models with the same casting conditions but different thicknesses were employed to analyze the hydrodynamic behavior at the top of the *** first model was a standard thickness slab,and the second had a thickness three times *** is found with the second model that above the plane formed by the steel jets,it is possible to observe four three-dimensional vortexes that interact with the submerged entry nozzle（SEN）and mold *** using a biphasic model to simulate the interface between the liquid and air inside the mold,the flow asymmetry and the fluctuations of the free surface can be clearly observed.

关键词： continuous casting molds flow patterns three dimensional vortes mathematical models computer simulation

Complementarity of electric vehicles and pumped-hydro as energy storage in small isolated energy systems:case of La Palma,Canary Islands

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Journal of Modern Power Systems and Clean Energy 2016年第4期4卷 604-614页

作者： Alfredo RAMIREZ-DIAZ Francisco J.RAMOS-real Gustavo A.MARRERO Departamento de Economı´a Contabilidad y FinanzasFacultad de Economı´aEmpresa y TurismoUniversidad de La Laguna38071 La LagunaSpain Instituto Universitario de Ciencias Polı´ticas y Sociales Universidad de La Laguna38071 La LagunaSpain Instituto Universitario de Desarrollo Regional Universidad de La Laguna38071 La LagunaSpain

Isolated energy systems in archipelagos are characterized for having a great dependence on fossil sources due to isolation and territorial *** island of La Palma is situated on the northwest of the Canary Islands,and its electric system is very *** policies planned by local authorities are aimed to increase the share of renewable energies and the reduction of fossil ***,intermittence and the concentration of unmanageable renewable energies in few locations may hinder the operation of the *** order to solve these problems,energy storage plays an essential *** aim of this paper is to analyse the effects of the introduction of two possible alternatives as a way of energy storage:pumped hydro storage and electric *** this,we use a simulation model adapted to the features of La Palma,considering different *** show that,in the most favourable scenario,the installation of an additional 25 MW from renewables(more than double the current power),supported by 20 MW of pumped hydro storage and a fleet of 3361 electric vehicles,would allow the current share of renewables to increase from11%(in 2015)to 49%.Furthermore,this would mean a 26%reduction in CO2 emissions,10%in costs of generated k Wh and 19%in energy dependence.

关键词： Energy storage Electric vehicles Vehicle-to-grid Grid-for-vehicles Pumped-hydro energy storage Isolated systems

Observation of dipolar transport in one-dimensional photonic lattices

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Science Bulletin 2017年第5期62卷 339-344页

作者： Camilo Cantillano Luis Morales-Inostroza Bastián real Santiago Rojas-Rojas Aldo Delgado Alexander Szameit Rodrigo A.Vicencio Departamento de Física MSI-Nucleus on Advanced Opticsand Center for Optics and Photonics(CEFOP)Facultad de CienciasUniversidad de ChileSantiagoChile Center for Optics and Photonics and MSI-Nucleus on Advanced Optics Universidad de ConcepciónCasilla 160-C ConcepcionChile Institute for Physics University of RostockD-18059 RostockGermany

We experimentally study the transport properties of dipolar and fundamental modes on one dimensional(1D) coupled waveguide arrays. By carefully modulating a wide optical beam, we are able to effectively excite dipolar or fundamental modes to study discrete diffraction(single-site excitation) and gaussian beam propagation(multi-site excitation plus a phase gradient). We observe that dipolar modes experience a larger spreading area due to an effective larger coupling constant, which is found to be more than two times larger than the one for fundamental modes. Additionally, we study the effect of non-diagonal disorder and find that while fundamental modes are already trapped on a weakly disorder array, dipoles are still able to propagate across the system.

关键词： Photonic lattices Waveguide arrays Wave propagation Integrated optics

Derailment risk and dynamics of railway vehicles in curved tracks： Analysis of the effect of failed fasteners

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Journal of Modern Transportation 2016年第1期24卷 38-47页

作者： Silvia Morales-Ivorra Julia Irene real Cesar Hernandez Laura Montalbain University Institute for Multidisciplinary Mathematics Polytechnic University of Valencia 46022 Valencia Spain

The effect of the fastener＇s failure in a railway track on the dynamic forces produced in the wheel-rail contact is studied using the simulation software VAMPIRE to assess the derailment risk of two different vehicles in two curves with distinct characteristics. First, a 3D-FEM model of a real track is constructed, paying special attention to fasteners, and calibrated with displacement data obtained experimentally during a train passage. This numerical model is subsequently used to determine the track vertical and lateral stiffness. This study evidences that although the track can practically lose its lateral stiffness as a consequence of the failure of 7 consecutive fasteners, the vehicle stability would not be necessarily compromised in the flawed zone. Moreover, the results reveal that the uncompensated acceleration and the distance along which the fasteners are failed play an important role in the dynamic behavior of the vehicle-track system, influencing strongly the risk of derailment.

关键词： Railway dynamics Fasteners Derailment Curved track

A Computer-Aided FPS-Oriented Approach for Construction Briefing

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Tsinghua Science and Technology 2008年第S1期13卷 292-297页

作者： Xiaochun Luo, Qiping Shen Department of Building and real Estate, the Hong Kong Polytechnic University, Hong Kong, China Department of Building and real Estate the Hong Kong Polytechnic University Hong Kong China

Function performance specification (FPS) is one of the value management (VM) techniques developed for the explicit statement of optimum product definition. This technique is widely used in software engineering and manufacturing industry, and proved to be successful to perform product defining tasks. This paper describes an FPS-oriented approach for construction briefing, which is critical to the successful delivery of construction projects. Three techniques, i.e., function analysis system technique, shared space, and computer-aided toolkit, are incorporated into the proposed approach. A computer-aided toolkit is developed to facilitate the implementation of FPS in the briefing processes. This approach can facilitate systematic, efficient identification, clarification, and representation of client requirements in trail running. The limitations of the approach and future research work are also discussed at the end of the paper.

关键词： briefing value management (VM) functional performance specification (FPS) function analysis system technique shared space computer-aided