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Light(Science & Applications) 2016年第1期5卷 788-795页

作者： Andrey Denisov marcelo A soto Luc Thévenaz EPFL Swiss Federal Institute of Technology Group for Fiber Optics(GFO)SCI-STI-LTStation 11CH-1015 LausanneSwitzerland

Distributed fiber sensing possesses the unique ability to measure the distributed profile of an environmental quantity along many tens of kilometers with spatial resolutions in the meter or even centimeter *** feature enables distributed sensors to provide a large number of resolved points using a single optical ***,in current systems,this number has remained constrained to a few hundreds of thousands due to the finite signal-to-noise ratio(SNR)of the measurements,which imposes significant challenges in the development of more performing ***,we propose and experimentally demonstrate an ultimately optimized distributed fiber sensor capable of resolving 2100000 independent points,which corresponds to a one-orderof-magnitude improvement compared to the *** a Brillouin distributed fiber sensor based on phase-modulation correlation-domain analysis combined with temporal gating of the pump and time-domain acquisition,a spatial resolution of 8.3 mm is demonstrated over a distance of 17.5 *** sensor design addresses the most relevant factors impacting the SNR and the performance of medium-to-long range sensors as well as of sub-meter spatial resolution *** step record in the number of resolved points could be reached due to two theoretical models proposed and experimentally validated in this study:one model describes the spatial resolution of the system and its relation with the sampling interval,and the other describes the amplitude response of the sensor,providing an accurate estimation of the SNR of the measurements.

关键词： distributed fiber sensors optical fibers stimulated Brillouin scattering

Cost-effectiveness of enhanced liver fibrosis test to assess liver fibrosis in chronic hepatitis C virus and alcoholic liver disease patients

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World Journal of Gastroenterology 2017年第17期23卷 3163-3173页

作者： marcelo soto Laura Sampietro-Colom Luis Lasalvia Aurea Mira Wladimiro Jiménez Miquel Navasa FundacióClínic per a la Recerca Biomèdica Health Technology Assessment Unit Hospital Clínic Siemens Healthcare Department of Clinical Microbiology Hospital Clínic Department of Biomedicine University of Barcelona IDIBAPS7.Liver Unit Hospital Clínic

AIM To assess liver fibrosis(LF) in hepatitis C virus(HCV) and alcoholic liver disease(ALD), estimate health outcomes and costs of new noninvasive testing strategies METHODS A Markov model was developed to simulate LF progression in HCV and ALD for a cohort of 40-yearold men with abnormal levels of transaminases. Three different testing alternatives were studied: a single liver biopsy; annual Enhanced liver fibrosis(ELF?) followed by liver stiffness measurement(LSM) imaging as a confirmation test if the ELF test is positive; and annual ELF test without LSM. The analysis was performed from the perspective of a university hospital in *** data were obtained from published literature. Costs were sourced from administrative databases of the hospital. Deterministic and probabilistic sensitivity analyses were *** In HCV patients, annual sequential ELF test/LSM and annual ELF test alone prevented respectively 12.9 and 13.3 liver fibrosis-related deaths per 100 persons tested, compared to biopsy. The incremental costeffectiveness ratios(ICERs) were respectively €13400 and €11500 per quality-adjusted life year(QALY). In ALD, fibrosis-related deaths decreased by 11.7 and 22.1 per 100 persons tested respectively with sequential ELF test/LSM and annual ELF test alone. ICERs were €280 and €190 per QALY, *** The use of the ELF test with or without a confirmation LSM are cost-effective options compared to a single liver biopsy for testing liver fibrosis in HCV and ALD patients in Spain.

关键词： Cost-effectiveness analysis Liver fibrosis Noninvasive diagnostic assessment Alcoholic liver disease Hepatitis C

Strain-Insensitive Fiber Bragg Grating Composite Structure for Wide-Range Temperature Sensing

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Journal of Dynamics, Monitoring and Diagnostics 2024年第3期3卷 199-206页

作者： Pingyu Zhu Tingyu Huang Sheng Fan Yukun Yan Bo Peng Danli Xiong Shuai Zhang marcelo A.soto School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhouChina Zhuzhou Times New Material Technology Co. LtD.ZhuzhouChina Department of Electronics Engineering Universidad Técnica Federico Santa MaríaValparaísoChile

This paper reports on the design,fabrication,and temperature strain sensing performance of a fiber Bragg grating composite structure for surface mounted temperature measurements over a wide temperature range,with highly reduced strain *** fiber Bragg grating sensor is encapsulated in a polyimide tube filled with epoxy resin,forming an arc-shaped *** assembly is then placed between two layers of glass fiber prepreg with a flexible pad in between and cured into *** results,supported by finite element simulations,demonstrate an enhanced temperature sensitivity is 26.3 pm/°C over a wide temperature range of–30°C to 70°C,and high strain transfer isolation of about 99.65%.

关键词： composite structure fiber bragg grating temperature sensing

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Weathering Trump2.0

China Today 2025年第1期74卷 20-21页

作者： AUGUSTO soto Dialogue with China Project in Barcelona Spain

While the 47^(th) *** has declared a trade war on all nations,China has the strength to get ahead despite the complex rivalry.“History doesn’t repeat itself,but it often rhymes.”This saying by celebrated American writer Mark Twain,a contemporary of the American Civil War(1861-1865)and the Crimean War(1853-1856),resonates uncannily once again as Donald Trump takes charge in the United States.

关键词： Trump saying contemporary

Cryotic climate conditions and their eventual implication in the high-mountain surface of the Nevado de Toluca volcano, Mexico

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Journal of Mountain Science 2021年第9期18卷 2273-2286页

作者： soto Victor Facultad de Ciencias Biológicas y Agropecuarias Universidad VeracruzanaPoza Rica-Tuxpan 92870México

The state of the cryosphere in tropical regions is of great importance because the temperature around the glaciers, permafrost and snow cover always fluctuates near the melting point. These thermal conditions and their high sensitivity to climate change cause the accelerated disappearance of these elements;therefore, it is important to know the climatic factors that regulate them, as well as the physical characteristics of each cryospheric element. Unlike glaciers, permafrost and snow cover have not been widely studied. In recent decades, the study of the glacial and periglacial environment has been carried out in intertropical mountains. However, despite the altitude of their relief and the frequent occurrence of snowfall in tropical high mountains, the conditions that determine such events have been barely analyzed;and in the case of Mexico, the volume of snowfall and its thickness have not been quantified either, as well as their corresponding duration. Consequently, this work is aimed to analyze the temperature and precipitation conditions that determine the snowfall at the higher part of the Nevado de Toluca volcano;at the same time, the conditions of the cryotic climate and their possible implication on the surface are studied. The analysis of data from 1965 to 2016, using frequency statistics, allowed to realize that snowfall occurs with low intensity, its accumulation being less than 10 cm thick and 10 mm of snow water equivalent, which causes the snowpack to stay only a few weeks on average. At the same time, it was determined that there is a significant increase in the number of freeze-thaw cycles. Therefore, due to the climate conditions and their influence on the mountain surface, it is probable that the bedrock is subject to a greater gelifraction dynamics, and the unconsolidated soil surface increases;the combination of the above could cause a greater geomorphological dynamic over time, particularly due to debris flows, and by water and wind erosion of

关键词： Air temperature Cryotic conditions High-mountain climatology Periglacial geomorphology Snow precipitation

Bedrock outcropping in the accumulation zone of the largest glacier in Mexico(Glaciar Norte of Citlaltépetl),as evidence of a possible accelerated extinction

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Journal of Mountain Science 2023年第2期20卷 338-354页

作者： soto Víctor Colegio de Geografía Facultad de EconomíaUniversidad VeracruzanaAv.Xalapa s/nObrero Campesina91020XalapaVer.México

The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the *** of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is ***,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been ***,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in *** to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed *** study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study ***,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is *** rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier ***,the ascent of the glacial front to 5102 m *** the modelled altitude of the equilibrium line to 5276 m *** reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done

关键词： Bedrock outcrop Citlaltépetl glacier Glacial accumulation zone Glacier retreat Glacial thickness

Oil recovery tests with ionic liquids: A review and evaluation of 1-decyl-3-methylimidazolium triflate

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Petroleum Science 2022年第4期19卷 1877-1887页

作者： Alba Somoza Alberto Arce Ana soto CRETUS Department of Chemical EngineeringUniversidade de Santiago de CompostelaE-15782Santiago de CompostelaSpain School of Engineering Universidade de A CorunaE-15403FerrolSpain

The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve current chemical oil recovery methods has been presented, focusing on core flooding experiments. With an almost infinite number of possible ionic liquids, the amount of experiments carried out up to now has been very limited. However, results are promising, with additional recovery after secondary flooding of up to 32% of the original oil in place. Most formulations with ionic liquids have been proposed for sandstone reservoirs, the number of studies with carbonate cores being very scarce. The possibilities of a new room temperature surface active ionic liquid, 1-decyl-3-methylimidazolium triflate,for this application were analyzed. It was shown that it is able to drastically reduce the water/oil interfacial tension. An optimized formulation was proposed for carbonate reservoirs. After secondary flooding with brine, an additional recovery of 10.5% of original oil in place was achieved at room conditions. A combination of the proposed method followed by a polymer flooding step with polyacrylamide led to a lesser but still significant recovery, reducing the costs associated to the ionic liquid.

关键词： Enhanced oil recovery(EOR) Ionic liquids Core flooding Interfacial tension 1-Decyl-3-methylimidazolium triflate

Binary Fruit Fly Swarm Algorithms for the Set Covering Problem

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Computers, Materials & Continua 2022年第6期71卷 4295-4318页

作者： Broderick Crawford Ricardo soto Hanns de la Fuente Mella Claudio Elortegui Wenceslao Palma Claudio Torres-Rojas Claudia Vasconcellos-Gaete marcelo Becerra Javier Pena Sanjay Misra Pontificia Universidad Católica de Valparaíso Valparaíso2362807Chile LERIA Universitéd’AngersAngers49000France Department of Computer Science and Communication Ostfold University CollegeHaldenNorway

Currently,the industry is experiencing an exponential increase in dealing with binary-based combinatorial *** this sense,metaheuristics have been a common trend in the field in order to design approaches to solve them ***,a well-known strategy consists in the use of algorithms based on discrete swarms transformed to perform in binary *** the No Free Lunch theorem,we are interested in testing the performance of the Fruit Fly Algorithm,this is a bio-inspired metaheuristic for deducing global optimization in continuous spaces,based on the foraging behavior of the fruit fly,which usually has much better sensory perception of smell and vision than any other *** the other hand,the Set Coverage Problem is a well-known NP-hard problem with many practical applications,including production line balancing,utility installation,and crew scheduling in railroad and mass transit *** this paper,we propose different binarization methods for the Fruit Fly Algorithm,using Sshaped and V-shaped transfer functions and various discretization methods to make the algorithm work in a binary search *** are motivated with this approach,because in this way we can deliver to future researchers interested in this area,a way to be able to work with continuous metaheuristics in binary *** new approach was tested on benchmark instances of the Set Coverage Problem and the computational results show that the proposed algorithm is robust enough to produce good results with low computational cost.

关键词： Set covering problem fruit fly swarm algorithm metaheuristics binarization methods combinatorial optimization problem

Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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Journal of Forestry Research 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-Salazar Marcela Rosas-Chavoya Marín Pompa-García Pablito marcelo López-Serrano Emily García-Montiel Arnulfo Meléndez-soto Sergio Iván Jiménez-Jiménez Instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Instituto de Silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-CENID RASPA Centro Nacional de Investigación Disciplinaria en Relación Agua-Suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from NASA/POWER *** ANOVA explored possible differences in NDVI among the three *** correlation was performed to identify the linear relationship between NDVI and meteorological *** differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

Traces of weighted function spaces: Dyadic norms and Whitney extensions

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Science China Mathematics 2017年第11期60卷 1981-2010页

作者： KOSKELA Pekka soto Tomas WANG Zhuang Department of Mathematics and Statistics University of Jyvskyl

The trace spaces of Sobolev spaces and related fractional smoothness spaces have been an active area of research since the work of Nikolskii, Aronszajn, Slobodetskii, Babich and Gagliardo among others in the 1950's. In this paper, we review the literature concerning such results for a variety of weighted smoothness spaces. For this purpose, we present a characterization of the trace spaces(of fractional order of smoothness),based on integral averages on dyadic cubes, which is well-adapted to extending functions using the Whitney extension operator.

关键词： trace theorems weighted Sobolev spaces Besov spaces Triebel-Lizorkin spaces