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Eventual Leader Election with Weak Assumptions on Initial Knowledge,Communication Reliability,and Synchrony

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Journal of.Computer Science & Technology 2010年第6期25卷 1267-1281页

作者： Antonio f.rnndez Anta Ernesto jimnez Michel Raynal Institute IMDEA Networks Avenida del Mar Mediterraneo EUI Universidad Politcnica de Madrid IRISA Universit de Rennes

This paper considers the eventual leader election problem in asynchronous message-passing systems where an arbitrary number t of.processes can crash（t〈n,where n is the total number of.processes）.It considers weak assumptions both on the initial knowledge of.the processes and on the network *** precisely,initially,a process knows only its identity and the f.ct that the process identities are dif.erent and totally ordered（it knows neither n nor t）.Two eventual leader election protocols and a lower bound are *** f.rst protocol assumes that a process also knows a lower bound α on the number of.processes that do not *** protocol requires the f.llowing behavioral properties f.om the underlying network：the graph made up of.the correct processes and f.ir lossy links is strongly connected,and there is a correct process connected to（n〈f.-α other correct processes（where f.is the actual number of.crashes in the considered run） through eventually timely paths（paths made up of.correct processes and eventually timely links）.This protocol is not communication-ef.icient in the sense that each correct process has to send messages *** second protocol is communication-ef.icient：af.er some time,only the f.nal common leader has to send messages *** protocol does not require the processes to know α,but requires stronger properties f.om the underlying network：each pair of.correct processes has to be connected by f.ir lossy links（one in each direction）,and there is a correct process whose n〈f.1 output links to the rest of.correct processes have to be eventually timely.A matching lower bound result shows that any eventual leader election protocol must have runs with this number of.eventually timely links,even if.all processes know all the processes *** addition to being communication-ef.icient,the second protocol has another noteworthy ef.iciency property,namely,be the run f.nite or inf.nite,all the local variables and message f.elds have

关键词： eventually timely and f.ir lossy links eventual leader election f.ilure detector omega leader oracle process initial knowledge

The relation between ductility at high temperature and solid solution in Mg alloys

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Journal of.Magnesium and Alloys 2022年第1期10卷 241-256页

作者： D.f.Shi C.M.Cepeda-jiménez M.T.Pérez-Prado IM DEA Materials Institute C/Eric Ka ridel228906 GetafeMadridSpain Department of.Materials Science Polytechnic University of Madrid/Universidad Politecnica de MadridE.T.S.de Ingenieros de Caminos28040MadridSpain Department of.Physical Metallurgy CENIMCSICAv.Gregorio del Amo 828040 MadridSpain

This work investigates the ef.ect of.solid solution on ductility and on the activation of.individual def.rmation mechanisms at moderate temperatures and at quasi-static strain rates in Mg-Zn and Mg-Al alloys. With that aim, f.ur solid solution Mg-Zn and Mg-Al binary alloy ingots containing 1 and 2 wt.% solute atoms were subjected to hot rolling and subsequent annealing to generate polycrystals with similar average grain size and basal-type texture f.r each composition. The activity of.the dif.erent slip systems af.er tensile testing at 150°C and at 250°C was evaluated in pure Mg and in the alloys by EBSD-assisted slip trace analysis. In addition, segregation of.Zn and Al atoms at grain boundaries during the thermo-mechanical processing was characterized by HAADf.STEM and EDX. It was f.und that while the addition of.Al and Zn atoms to pure Mg does not lead to major changes in the mechanical strength at the investigated temperatures, it does enhance ductility signif.cantly, especially at 250℃. Our results show that this increase in ductility cannot be attributed to a higher activation of.non-basal systems in the alloys, as reported earlier, as the incidence of.non-basal systems is indeed considerably higher in pure Mg. This work suggests, on the contrary, that the ductility increase may be attributed to the presence of.a more homogenous basal activity in the alloys due to a lower degree of.orientation clustering, to grain boundary solute segregation, and to a higher slip dif.usivity at grain interiors.

关键词： Magnesium Solute segregation Slip trace analysis Ductility Def.rmation mechanisms

Lipschitz Algebras and Peripherally-multiplicative Maps

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Acta Mathematica Sinica,English Series 2008年第8期24卷 1233-1242页

作者： A.jim■nez-VARGAS Moisés VILLEGAS-VALLECILLOS Departamento de■lgebray Análisis Matemático Universidad de Almería04071AlmeríaSpain

Let X be a compact metric space and let Lip（X） be the Banach algebra of.all scalar- valued Lipschitz f.nctions on X, endowed with a natural norm. f.r each f.∈ Lip（X）, σπ（f. denotes the peripheral spectrum of.f. We state that any map Φ f.om Lip（X） onto Lip（Y） which preserves multiplicatively the peripheral spectrum： σπ（Φ（f.Φ（g）） = σπ（f.）, A↓f. g ∈ Lip（X） is a weighted composition operator of.the f.rm Φ（f. = τ· （f.°φ） f.r all f.∈ Lip（X）, where τ ： Y → {-1, 1} is a Lipschitz f.nction and φ ： Y→ X is a Lipschitz homeomorphism. As a consequence of.this result, any multiplicatively spectrum-preserving surjective map between Lip（X）-algebras is of.the f.rm above.

关键词： Lipschitz algebra peripherally-multiplicative map spectrum-preserving map peaking f.nction peripheral spectrum

Zebraf.sh as a possible bioindicator of.organic pollutants with ef.ects on reproduction in drinking waters

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Journal of.Environmental Sciences 2015年第7期27卷 254-260页

作者： M.Martínez-Sales f.García-Ximénez f.J.Espinós Aquaculture and Environmental Research Group (ACUMA) Polytechnic University of Valencia

Organic contaminants can be detected at low concentrations in drinking water, raising concerns f.r human health, particularly in reproduction. In this respect, we attempted to use the zebraf.sh as a bioindicator to detect the possible presence of.these substances in drinking water, aiming to def.ne the most relevant parameters to detect these substances, which particularly af.ect the development and reproduction of.zebraf.sh. To this end, batches of.0 embryos with the chorion intact were cultured in drinking waters f.om dif.erent sources,throughout their f.ll lif.-cycle up to 5 months, in 20 L tanks. Six replicates were perf.rmed in all water groups, with a total of.24 aquariums. Two generations（f. and f.） were studied and the f.llowing parameters were tested： in the f. generation, survival and abnormality rates evaluated at 5 dpf.days post-f.rtilization） and at 5 mpf.months post-f.rtilization）,the onset of.spawning and the f.rtility rate f.om 3 mpf.to 5 mpf. and the sex ratio and underdeveloped specimens at 5 mpf. f.rthermore, in the f. of.spring（f.）, survival and abnormality rates were evaluated at 5 dpf.and the hatching rate at 72 hpf. These results revealed that the hatching rate is the most sensitive parameter to distinguish dif.erent levels of.ef.ects between waters during the early lif. stages, whereas the rate of.underdeveloped specimens is more suitable at later lif. stages. Regarding adult reproduction, f.rtility rate was the most sensitive parameter. The possible reversibility or accumulative nature of.such ef.ects will be studied in f.ture work.

关键词： Organic pollutants Bioindicator Development and reproduction parameters Drinking water Zebraf.sh

Metamorphic gradient modif.cation in the Early Cretaceous Northern Andes subduction zone:A record f.om thermally overprinted high-pressure rocks

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Geoscience f.ontiers 2022年第2期13卷 354-371页

作者： D.S.Avellaneda-jiménez A.Cardona V.Valencia S.León I.f.Blanco-Quintero Grupo de Investigación en Geología y Geof.sica(EGEO) Universidad Nacional de ColombiaMedellínColombia Departamento de Materiales y Minerales Universidad Nacional de ColombiaMedellínColombia Departamento de Procesos y Energía Universidad Nacional de ColombiaMedellínColombia School of.the Environment Washington State UniversityPullmanUSA Smithsonian Tropical Research Institute BalboaAnconPanama Departamento de Ciencias de la Tierraydel Medio Ambiente Universidad de AlicanteSpain

New f.eld observations and petrological data f.om Early Cretaceous metamorphic rocks in the Central Cordillera of.the Colombian Andes allowed the recognition of.thermally overprinted high-pressure rocks derived f.om oceanic crust *** obtained metamorphic path suggests that the rocks evolved f.om blueschist to eclogite f.cies towards upper amphibolite to high-pressure granulite f.cies transitional *** f.cies conditions,better recorded in maf.c protoliths,are revealed by relic lawsonite and phengite,bleb-to worm-like diopside-albite symplectites,as well as garnet core *** amphibolite to high pressure granulite f.cies overprinting is supported by coarse-grained brown-colored Ti-rich amphibole,augite,and oligoclase recrystallization,as well as the record of.partial melting *** equilibria and pressure-temperature(P-T)path modeling suggest initial high-pressure metamorphic conditions M1 yielding 18.2-24.5 kbar and 465-580℃,f.llowed by upper amphibolite to high pressure granulite f.cies overprinting stage M2 yielding 6.5-14.2 kbar and 580-720℃.Retrograde conditions M3 obtained through chlorite thermometry yield temperatures ranging around 286-400℃at pressures below 6.5-11 *** obtained clockwise P-T path,the garnet zonation pattern revealing a decrease in X_(grs)/X_(prp)related to Mg#increment f.om core to rim,the presence of.partial melting veins,as well as regional constraints,document the modif.cation of.the thermal structure of.the active subduction zone in Northern Andes during the Early *** increment of.the metamorphic gradient within the subduction interf.ce is associated with slab roll-back geodynamics where hot mantle inf.ow was *** scenario is also argued by the reported trench-ward magmatic arc migration and multiple extensional basin f.rmation during this *** presented example constitutes the f.rst report of.Cretaceous roll-back-related metamorphism in the Caribbean and Ande

关键词： Slab roll-back Mineral chemistry Phase equilibria P-T path modeling Roll-back metamorphism Thermally overprinted high-pressure rocks

Predicting grain size-dependent superplastic properties in f.iction stir processed ZK30 magnesium alloy with machine learning methods

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Journal of.Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： f.rid Bahari-Sambran f.rnando Carreno C.M.Cepeda-jiménez Alberto Orozco-Caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of.Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of.this work is to predict,f.r the f.rst time,the high temperature f.ow stress dependency with the grain size and the underlaid def.rmation mechanism using two machine learning models,random f.rest(Rf.and artif.cial neural network(ANN).With that purpose,a ZK30 magnesium alloy was f.iction stir processed(f.P)using three dif.erent severe conditions to obtain f.ne grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three f.iction stir processed samples clearly def.rmed by grain boundary sliding(GBS)def.rmation mechanism at high *** maximum elongations to f.ilure,well over 400% at high strain rate of.10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of.2.8μm,and at 300℃ f.r the f.nest grain size of.2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it dif.icult to assess the operative def.rmation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting f.ow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artif.cial intelligence Magnesium alloys Superplasticity f.iction stir processing Grain coarsening

Photocatalytic perf.rmance of.K2Ti6O13 whiskers to H2 evolution and CO2 photo-reduction

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Journal of.Energy Chemistry 2019年第10期28卷 18-28页

作者： L. f. Garay-Rodríguez L.M.Torres-Martínez E.Moctezuma f.cultad de Ingeniería Civil-Departamento de Ecomateriales y Energía Universidad Autónoma de Nuevo LeónAv. Universidad S/N Cd. UniversitariaC. P. 66455 San Nicolás de los GarzaNLMéxico f.cultad de Ciencias Químicas Universidad Autónoma de San Luis PotosíAv. Manuel Nava#6C. P.78290 San Luis PotosíSLPMéxico

K2Ti6O13 whiskers were synthesized by conventional sol-gel method, sono-chemical assisted and microwave assisted sol-gel method in order to obtain catalysts with dif.erent particle sizes and to modif. their optical, textural and electrochemical properties. These modif.cations improved their photocatalytic activity f.r H2 evolution and CO2 photo-reduction. Long K2Ti6O13 whiskers prepared by ultrasound assisted sol-gel method are the most active photocatalysts f.r the hydrogen evolution reaction using pure water as reactant (U-SG, 10,065 μmol g^-1). In contrast, an opposite behavior was observed using a mixture of.ethanol-water, where the highest activity was achieved by the shortest and less crystalline K2Ti6O13 whiskers (C-SG, 3,2871 μmol g^-1). In case of.CO2 photo-reduction, long whiskers that were also prepared by the sono-chemical assisted sol-gel method were the most active to transf.rm CO2 to f.rmaldehyde, methane, methanol and hydrogen. The Ef. value of.this catalyst is located very close to the potential f.r f.rmaldehyde production and f.vors the selectivity to this organic product.

关键词： K2Ti6O13 Sol-gel Whiskers Hydrogen evolution CO2 reduction

Automated Deep Learning Empowered Breast Cancer Diagnosis UsingBiomedical Mammogram Images

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Computers, Materials & Continua 2022年第6期71卷 4221-4235页

作者： JoséEscorcia-Gutierrez Romany f.Mansour Kelvin Belen Javier jiménez-Cabas Meglys Pérez Natasha Madera Kevin Velasquez Electronics and Telecommunications Engineering Program Universidad Autónoma del CaribeBarranquilla08001Colombia Department of.Mathematics Faculty of ScienceNew Valley UniversityEl-Kharga72511Egypt Mechatronics Engineering Program Universidad Autónoma del CaribeBarranquilla08001Colombia Department of.Computational Science and Electronic Universidad de la CostaCUCBarranquilla08001Colombia

Biomedical image processing is a hot research topic which helps to majorly assist the disease diagnostic *** the same time,breast cancer becomes the deadliest disease among women and can be detected by the use of.dif.erent imaging *** mammograms can be used f.r the earlier identif.cation and diagnostic of.breast cancer to minimize the death *** the proper identif.cation of.breast cancer has mainly relied on the mammography f.ndings and results to increased f.lse *** resolving the issues of.f.lse positives of.breast cancer diagnosis,this paper presents an automated deep learning based breast cancer diagnosis(ADL-BCD)model using digital *** goal of.the ADL-BCD technique is to properly detect the existence of.breast lesions using digital *** proposed model involves Gaussian f.lter based pre-processing and Tsallis entropy based image *** addition,Deep Convolutional Neural Network based Residual Network(ResNet 34)is applied f.r f.ature extraction ***,a hyper parameter tuning process using chimp optimization algorithm(COA)is applied to tune the parameters involved in ResNet 34 *** wavelet neural network(WNN)is used f.r the classif.cation of.digital mammograms f.r the detection of.breast *** ADL-BCD method is evaluated using a benchmark dataset and the results are analyzed under several perf.rmance *** simulation outcome indicated that the ADL-BCD model outperf.rms the state of.art methods in terms of.dif.erent measures.

关键词： Breast cancer digital mammograms deep learning wavelet neural network Resnet 34 disease diagnosis

Bioelectronic protein nanowire sensors f.r ammonia detection

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Nano Research 2020年第5期13卷 1479-1484页

作者： Alexander f.Smith Xiaomeng Liu Trevor L.Woodard Tianda f. Todd Emrick Juan M.jiménez Derek R.Lovley Jun Yao Department of.Biomedical Engineering University of MassachusettsAmherstMA 01003USA Department of.Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of.Microbiology University of MassachusettsAmherstMA 01003USA Department of.Polymer Science and Engineering University of MassachusettsAmherstMA 01003USA Department of.Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003USA Institute f.r Applied Lif. Sciences(IALS) University of MassachusettsAmherstMA 01003USA

Electronic sensors based on biomaterials can lead to novel green technologies that are low cost,renewable,and *** we demonstrate bioelectronic ammonia sensors made f.om protein nanowires harvested f.om the microorganism Geobacter *** nanowire sensor responds to a broad range of.ammonia concentrations(10 to 10^6 ppb),which covers the range relevant f.r industrial,environmental,and biomedical *** sensor also demonstrates high selectivity to ammonia compared to moisture and other common gases f.und in human *** results provide a proof.of.concept demonstration f.r developing protein nanowire based gas sensors f.r applications in industry,agriculture,environmental monitoring,and healthcare.

关键词： nanowire protein nanowire biomaterial bioelectronics biosensor ammonia sensor