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Prognosis of residual coal gas capacity made by the ‘Express' method

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 127-131页

作者： Pavel Prokop Pavel Zapletal ivo Pěgímek Technical University of Ostrava

An easy, reliable, and inexpensive method, called ＇Express＇ method, was described to determine the residual gas capacity of deep mines using results from an air and gas balance. Air and gas balances are common elements of mine management and must be performed periodically. Using the process described here to obtain balance results, it is straightforward to obtain the residual gas capacity, which is an important parameter for decision-making in current mine operations. After a mine is closed, the residual gas capacity becomes a dominant factor used to select methods to protect against gas emissions from the closed underground area or perhaps to provide information for the use of gas reserves. The proposed ＇Express＇ method is a much simpler method to obtain the residual gas capacity than other procedures used for this purpose to date.

关键词： coal mines gas storage methane ventilation degassing

Bogomolov Multipliers for Some p-groups of Nilpotency Class 2

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Acta Mathematica Sinica,English Series 2016年第5期32卷 541-552页

作者： ivo MICHAILOV Faculty of Mathematics and Informatics Shumen University "Episkop Konstantin Preslavski"

The Bogomolov multiplier B0 （g） of a finite group g is defined as the subgroup of the Schur multiplier consisting of the cohomology classes vanishing after restriction to all abelian subgroups of g. The triviality of the Bogomolov multiplier is an obstruction to Noether＇s problem. We show that if g is a central product of g1 and g2, regarding Ki ≤ Z（gi）,i = 1,2, and θ ： g1 →g2 is a group homomorphism such that its restriction θ｜K1 ： K1 → K2 is an isomorphism, then the triviality of Bo（g1/K1）, Bo（g1） and B0（g2） implies the triviality of Bo（g）. We give a positive answer to Noether＇s problem for all 2-generator p-groups of nilpotency class 2, and for one series of 4-generator p-groups of nilpotency class 2 （with the usual requirement for the roots of unity）.

关键词： Bogomolov multiplier Noether's problem rationality problem central product of groups p-groups of nilpotency class 2

New few parameters differential evolution algorithm with application to structural identification

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 1-14页

作者： Rita greco ivo Vanzi department of Civil Engineering Environmental Territory Building and Chemical Polytechnic University of Bari department of Engineering and geology University of Chieti-Pescara "G.d'Annunzio"

Differential evolution algorithm(deA) is a stochastic, population-based global optimization method. In this paper, we propose new schemes for both mutation and crossover operators in order to enhance the performances of the standard deA. The advantage of these proposed operators is that they are "parameters-less", without a tuning phase of algorithm parameters that is often a disadvantage of deA. Once the modified differential evolutions are presented, a large comparative analysis is performed with the aim to assess both correctness and efficiency of the proposed operators. Advantages of proposed deA are used in an important task of modern structural engineering that is mechanical identification under external dynamic loads. This is because of the importance of using a "parametersless" algorithm in identification problems whose characteristics typically vary strongly case by case, needing of a continuous set up of the algorithm proposed. This important advantage of proposed optimizers, in front of other identification algorithms, is used to develop a computer code suitable for the automatic identification of a simple supported beam subject to an impact load, that has been tested both using numerical simulations and real standard tests dynamic. The results point out that this algorithm is an interesting candidate for standard applications in structural identification problems.

关键词： Differential evolution Parametric identification Structural identification Optimization

Rhyacian-Orosirian tectonic history of the Juiz de Fora Complex:Evidence for an Archean crustal reservoir within an island-arc system

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geoscience Frontiers 2022年第5期13卷 350-369页

作者： Rasec Almeida Vitalino Elizeu Henrique Bruno Samuel Moreira Bersan Lucas Eduardo de Abreu Barbosa Araujo ivo Dussin Claudio de Morisson Valeriano Carla Neto Monica Heilbron Universidade do Estado do Rio de Janeiro Faculdade de GeologiaTektos–Grupo de Pesquisa em GeotectônicaRua São Francisco Xavier 524MaracanãRio de JaneiroBrazil Laboratório de geocronologia e Isótopos Radiogênicos Universidade do Estado do Rio de JaneiroRua São Francisco Xavier 524MaracanãRio de JaneiroBrazil

The southern São Francisco Paleocontinent(SFP)comprises Archean nuclei and Paleoproterozoic complexes encompassing magmatic arcs juxtaposed during a Rhyacian to Orosirian orogenic *** Juiz de Fora Complex(JFC)represents an imbricated thrust system that comprises orthogranulites with a wide compositional range formed in an intra-oceanic setting during the Siderian to the Orosirian and later accreted to the southeastern margin of the *** we report new petrological,geochemical,whole-rock Nd and Sr data,as well as zircon U–Pb ages from felsic and mafic orthogranulites from the *** new data is combined with a regional compilation that enables an evaluation of the interaction between magmatism and orogenetic episodes in the context of the consolidation of São Francisco Paleocontinent during the Rhyacian–*** collisional Island Arc tholeiites(IAT),Tonalites-Tron dhjemites-granodiorites(TTgs)and sanukitoid magmatism occurred from 2200 Ma to 2085 *** was followed by post-collisional magmatism,which is represented by hybrid granitoids coeval with the emplacement of E-MORB basic *** signatures for the Rhyacian to Orosirian evolution are highlighted by the dominance of negativeεNd(t)associated with Meso-to Neoarchean Nd TDMmodel ages as well as inherited zircon grains from the hybrid *** JFC is extensively highlighted in the literature as a primitive intra-oceanic arc,but here we propose the reworking or recycling of ancient crustal segments within the mature arc stage of the JFC,suggesting a Mesoarchean crustal source involved in the JFC evolution.

关键词： Juiz de Fora complex Paleoproterozoic magmatic arc TTg and sanukitoid São Francisco Paleocontinent

Discrete particle simulations of bubble-to-emulsion phase mass transfer in single-bubble fluidized beds

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Particuology 2017年第4期15卷 80-90页

作者： Lianghui Tan ivo Roghair Martin van Sint Annaland Chemical Process Intensification Multiphase Reactors Croup Department of Chemical Engineering & Chemistry Eindhoven University of Technology P.O.Box 513 5600 MB Eindhoven The Netherlands

A classical Euler-Lagrangian model for gas-solid flows was extended with gas component mass conser- vation equations and used to obtain fundamental insights into bubble-to-emulsion phase mass transfer in bubbling gas-solid fluidized beds. Simulations of injected single rising bubbles under incipient fiuidiza- tion conditions were carried out, using geldart-A and -B particles. Phenomena observed in the simulations and those of various theoretical models used to derive phenomenological models were compared to chal- lenge the assumptions underlying the phenomenological models. The bubble-to-emulsion phase mass transfer coefficients calculated for the simulations using geldart-B particles were in a good agreement with predictions made using the Davidson and Harrison （1963） model. The bubble-to-emulsion phase mass transfer coefficients for geldart-A particles were, however, much smaller than the predictions obtained from theoretical models （e.g. Chiba and Kobayashi （1970））. The newly developed model allows a detailed analysis of various hydrodynamic aspects and their effects on the mass transfer characteristics in and around rising bubbles in fluidized beds.

关键词： Mass transfer Discrete particle mode Fluidized bed Bubble-to-emulsion

Advanced Fiber-Optic Acoustic Sensors

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Photonic Sensors 2014年第3期4卷 198-208页

作者： Joao g. V. TEIXEIRA ivo T. LEITE Susana SILVA Orlando FRAZAO EQS group Rua Joaquim Dias Rocha 354 4470-221 Maia Portugal lNESC TEC (coordinated by INESC Porto) Rua Campo Alegre 687 4169-007 Porto Portugal department of Physics and Astronomy Faculty of Sciences- University of Porto Rua Campo Alegre 687 4169-007 Porto Portugal

Acoustic sensing is nowadays a very demanding field which plays an important role in modern society, with applications spanning from structural health monitoring to medical imaging. Fiber-optics can bring many advantages to this field, and fiber-optic acoustic sensors show already performance levels capable of competing with the standard sensors based on piezoelectric transducers. This review presents the recent advances in the field of fiber-optic dynamic strain sensing, particularly for acoustic detection. Three dominant technologies are identified - fiber Bragg gratings, interferometric Mach-Zehnder, and Fabry-Perot configurations - and their recent developments are summarized.

关键词： Acoustic sensors fiber optics optical fiber sensors

Ano malous weak values via a single phot on detection

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Light(Science & Applications) 2021年第6期10卷 963-968页

作者： Enrico Rebufello Fabrizio Piacentini Alessio Avella Muriel A.de Souza Marco gramegna Jan Dziewior Eliahu Cohen Lev Vaidman ivo Pietro degiovanni Marco genovese INRIM Strada delle Cacce 911-10135 TorinoItaly. National Institute of Metrology Quality and Technology-INMETROAv.Nossa Senhora das Granas50Duque de CaxiasRJ 25250-020Brazil. Max-Planck-lnstitut fur Quantenoptik Hans-Kopfermann-StraBe 185748 GarchingGermany. department fur Physik Ludwig-Maximilians-Universitat80797 MunchenGermany. Faculty of Engi neeri ng and the Institute of Nano tech nology and Advanced Materials Bar Ilan UniversityRamat Gan 5290002Israel. Raymond and Beverly Sackler School of Physics and Astronomy Tel-Aviv UniversityTel-Aviv 6997801Israel

Is it possible that a measurement of a spin component of a spin-1/2 particle yields the value 100?In 1988 Aharonov,Albert and Vaidman argued that upon pre-and postselection of particular spin states,weakening the coupling of a standard measurement procedure ensures this paradoxical *** theoretical prediction,called weak value,was realised in numerous experiments2-9,but its meaning remains very controversialsince its"anomalous"nature,i.e.z the possibility to exceed the eigenvalue spectrum,as well as its"quantumness"are *** address these questions by presenting the first experiment measuring anomalous weak values with just a single click,without the need for statistical *** measurement uncertainty is significantly smaller than the gap between the measured weak value and the nearest *** clarifying the meaning of weak values,demonstrating their non-statistical,single-particle nature,this result represents a breakthrough in understanding the foundations of quantum measurement,showing unprecedented measurement capability for further applications of weak values to quantum photonics.

关键词： quantum eigenvalue breakthrough

Predictability of refraction following immediate sequential bilateral cataract surgery(ISBCS)performed under general anaesthesia

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Eye and Vision 2015年第1期2卷 117-123页

作者： ivo guber Laurent Rémont Ciara Bergin Jules gonin Eye Hospital Foundation Asile des AveuglesUniversity of LausanneAvenue de France 151000 Lausanne 7VaudSwitzerland department of Ophthalmology Kantonsspital WinterthurZürichSwitzerland department of Ophthalmology CHU of LiègeUniversity of LiègeLiègeBelgium

Background:To evaluate the predictability of refraction following immediate sequential bilateral cataract surgery(ISBCS)performed under general ***:This is a retrospective review of all ISBCS performed at Kantonsspital Winterthur,Switzerland,between April 2000 and September *** case notes of 250 patients were *** having full refraction reported(110 patients/220 eyes)were included.210(95%)eyes had a straight forward phacoemulsification with posterior chamber intraocular lens implantation,seven eyes had a planned extracapsular cataract extraction(ECCE);three eyes had an intracapsular cataract ***:Both eyes of 110 patients(64 women,46 men)with a mean age of 79.0 years,standard deviation(SD)±11.4(range 26 to 97 years)were *** preoperative best corrected visual acuity(BCVA)was 0.5 LogMAR in the first eye,the interquartile range(IQR)was[0.4,1.2];0.7 LogMAR in the second eye with IQR[0.4,1.8].At one month,the median BCVA was 0.2 LogMAR,IQR[0.1,0.3]in the first eye,median BCVA was 0.1 LogMAR and IQR[0.0,0.5]in the second *** were 3 eyes(3%)that lost 3 lines or more in BCVA at one month(control ***-operatively).In all three cases,poor visual acuity had been recorded pre-operatively(>1 LogMAR).Achieved refraction was within±1.0 D of the target in 83%of *** were only 5%(n=6)of cases where if delayed sequential bilateral extraction had been performed could potentially intraocular lens(IOL)choice have been adjusted,in four of these cases,target refraction was within±1.0 D in the second ***:ISBCS performed under general anaesthesia achieves target refraction in 83%of eyes after consideration of complications,ocular co-morbidities and systemic *** the majority of cases where IOL power calculation could be considered,the achieved refraction of the second surgical eye was within±1.0 D of intended *** undermines the utility of IOL power adjustments in the second surgical

关键词： Cataract Cataract surgery Immediate sequential bilateral cataract surgery

guided resonance in negative index photonic crystals: a new approach

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Light(Science & Applications) 2014年第1期3卷 365-369页

作者： Silvia Romano Stefano Cabrini ivo Rendina Vito Mocella CNR-IMM-Unita di Napoli 80131 NapoliItaly Molecular Foundry Lawrence Berkeley National LaboratoryBerkeleyCAUSA

The behavior of a negative refraction photonic crystal slab irradiated with out-of-plane incident beam is an unexplored *** such an experimental configuration,guided mode resonance appears in the reflection *** show that,in this case,the light coupled inside the photonic crystal is backpropagating.A relationship with the negative index properties is established using a new approach in which the guided resonance is recovered by modeling the photonic crystal layer with a simple Lorentz resonator using the Fresnel reflection formula.

关键词： diffraction gratings guided mode resonance negative index photonic crystals