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High Voltage 2021年第5期6卷 822-835页

作者： Erika Stracqualursi rodolfo Araneo Amedeo Andreotti DIAEE-Electrical Engineering Division University of Rome“La Sapienza”RomeItaly Electrical Engineering Department University Federico II of NapoliNapoliItaly

In this study,the implementation of different corona discharge models in a transient program for overhead multiconductor lines based on the implicit Crank‐Nicolson Finite Difference Time Domain method is *** different corona models available in the literature,two empirical models(Gary's and Suliciu's models)and a physics‐based model(Malik's model)are discussed,which are broadly used in EMT programs,and their predictions under fast‐front lightning surges and slow‐front switching impulses are *** authors critically review the dynamic capacitance approach in terms of numerical accuracy,when dealing with slowly varying voltages,and applicability,regarding dispersive models assuming a non‐instantaneous charge‐voltage *** alternative voltage‐controlled generator approach is proposed,which is successfully included in the implicit Crank‐Nicolson *** of the objectives of this study is to show how different corona models may predict overvoltages with huge discrepancies,depending on the transient waveform and the propagation distance,despite the similarity of the q‐v hysteresis *** evident discrepancies between models under fast‐front voltage waves are reported,rather than for switching *** consistency of these results in terms of the models'features and q‐v curves is analysed,highlighting the necessity for new engineering tools for corona simulation of general predictive capability.

关键词： conductor transient dealing

Expanding treatment strategies for hepatocellular carcinoma patients: postoperative adjuvant transarterial chemoembolization

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Hepatobiliary Surgery and Nutrition 2020年第1期9卷 59-61页

作者： rodolfo Sacco Antonio Facciorusso Gastroenterology Unit Department of Medical SciencesUniversity of FoggiaFoggiaItaly

In spite of the recent improvements in diagnostic and treatment options for hepatocellular carcinoma (HCC) patients, with an increasing number of patients diagnosed in early stage and offered more effective therapies, the high recurrence rates even after radical treatments, such as surgery or radiofrequency ablation, still represent an unsolved issue (1).

关键词： patients hepatocellular treatment

A Comparison of Semi-Lagrangian and Lagrange-Galerkin hp-FEM Methods in Convection-Diffusion Problems

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Communications in Computational Physics 2011年第4期9卷 1020-1039页

作者： pedro Galan del Sastre rodolfo Bermejo Departamento de Matematica Aplicada al Urbanismo a la Edificacion y al Medio AmbienteE.T.S.A.M.Universidad Politecnica de MadridAvda.Juan de Herrera 428040 MadridSpain Departamento de Matematica Aplicada E.T.S.I.I.Universidad Politecnica de MadridC/Jose Gutierrez Abascal 228006 MadridSpain

We perform a comparison in terms of accuracy and CPU time between second order BDF semi-Lagrangian and Lagrange-Galerkin schemes in combination with high order finite element *** numerical results show that for polynomials of degree 2 semi-Lagrangian schemes are faster than Lagrange-Galerkin schemes for the same number of degrees of freedom,however,for the same level of accuracy both methods are about the same in terms of CPU *** polynomials of degree larger than 2,Lagrange-Galerkin schemes behave better than semi-Lagrangian schemes in terms of both accuracy and CPU time;specially,for polynomials of degree 8 or ***,we have performed tests on the parallelization of these schemes and the speedup obtained is quasi-optimal even with more than 100 processors.

关键词： Navier-Stokes equations convection-diffusion equations semi-Lagrangian LagrangeGalerkin second order backward difference formula hp-finite element method

A Model of a Quantum Particle in a Quantum Environment: A Numerical Study

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Communications in Computational Physics 2015年第6期18卷 247-262页

作者： Raffaele Carlone rodolfo Figari Claudia Negulescu Universita Federico II di Napoli Dipartimento di Matematica e Applicazioni“R.Caccioppoli”MSA I-80126 NapoliItaly Universita Federico II di Napoli Dipartimento di Fisica e INFN Sezione di NapoliMSA I-80126 NapoliItaly Universite de Toulouse&CNRS UPSInstitut de Mathematiques de Toulouse UMR 5219F-31062 ToulouseFrance

We define and investigate,via numerical analysis,a one dimensional toymodel of a cloud *** energetic quantum particle,whose initial state is a superposition of two identical wave packets with opposite average momentum,interacts during its evolution and exchanges(small amounts of)energy with an array of localized *** by the interaction with the environment,the initial superposition state turns into an incoherent sum of two states describing the following situation:or the particle is going to the left and a large number of spins on the left side changed their states,or the same is happening on the right *** evolution is reminiscent of what happens in a cloud chamber where a quantum particle,emitted as a spherical wave by a radioactive source,marks its passage inside a supersaturated vapour-chamber in the form of a sequence of small liquid bubbles arranging themselves around a pssible classical trajectory of the particle.

关键词： Schrodinger equation quantum particle+environment model multi-channel point interactions Wilson cloud chamber trace formation decoherence numerical discretization

Yield stress measurements and microstructure of colloidal kaolin powders clusterized and dispersed in different liquids

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Particuology 2009年第6期7卷 438-444页

作者： Dario T.Beruto Alberto Lagazzo rodolfo Botter Roberto Grillo Department of Civil Environmental and Architectural Engineering (DICAT)University of GenoaP.le Kennedy (Fiera del Mare)Pad. D16129-GenoaItaly Artigo S.p.A. loc.Carpeneto17014-Cairo Montenotte (SV)Italy

Rheologicat measurements of four colloidal kaolin powders dispersed in water, paraffinic oil and liquid rubber have been done at solid concentration （9 （VS/VL） in the range 8-33%. In quasi-static conditions the yield stress τ° values were derived. An S-shaped relationship between τ° and （9 exists, that allows to evaluate the percolation threshold θc values. In water θc ranges between 29% and 33%, while it is between 17% and 21% in oil and in liquid rubber. In water the microstructure units, i.e. the primary clusters among kaolin crystallites, are denser and bigger than the ones in the two other liquids. Furthermore, in quasistatic condition, the aqueous microstructure units have less tendency to cling together to form a network that can span all over the liquid phase. The different kaolin dispersions at θ equal to 22% are characterized by yield stress ranging between 7.S Pa and 59 Pa in water, 66-250 Pa in oil and 230-770 Pa in liquid rubber. It has been found that for any kaolin types the log τ°/ θ evaluated near to the percolation threshold is a conservative parameter of the three different liquids. These results are useful to design colloidal dispersions with selected microstructure.

关键词： Yield stress Colloid Dispersions Microstructure units Cluster Kaolin Rheology

Differences in physiological integration between invasive and noninvasive introduced clonal species of Carpobrotus

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Journal of Plant Ecology 2019年第6期12卷 972-981页

作者： Sergio R.Roiloa peter Alpert rodolfo Barreiro BioCost Group Biology DepartmentUniversidade da CoruñaA CoruñaSpain Biology Department University of MassachusettsAmherstMA 01003USA

Aims Clonal growth is associated with invasiveness in introduced plant species,but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie *** test the hypothesis that greater capacity to increase clonal growth via physiological integration of connected ramets increases invasiveness in clonal plants,we compared the effects of severing connections on accumulation of mass in the two species of the creeping,succulent,perennial,herbaceous genus Carpobrotus that have been introduced on sand dunes along the Pacific Coast of northern California,the highly invasive species Carpobrotus edulis and the co-occurring,noninvasive species Carpobrotus *** Pairs of ramets from four mixed populations of the species from California were grown in a common garden for 3 months with and without severing the stem connecting the *** simulate the effect of clones on soils in natural populations,the older ramet was grown in sand amended with potting compost and the younger in sand *** Findings Severance decreased net growth in mass by~60%in *** and~100%in ***,due mainly to the negative effect of severance on the shoot mass of the younger ramet within a *** to the hypothesis,this suggests that physiological integration increases growth more in the less invasive ***,severance also decreased allocation of mass to roots in the older ramet and increased it in the younger ramet in a pair,and the effect on the younger ramet was about twice as great in *** as in *** indicates that the more invasive species shows greater phenotypic plasticity in response to physiological integration,in particular greater capacity for division of *** could contribute to greater long-term growth and suggests that the division of labor may be a trait that underlies the association between clonal growth and invasiveness in plants.

关键词： biomass allocation Carpobrotus clonal growth physiological integration plant invasions

An experimental model of vitreous motion induced by eye rotations

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Eye and Vision 2015年第1期2卷 85-94页

作者： Andrea Bonfiglio Alberto Lagazzo rodolfo Repetto Alessandro Stocchino Department of Civil Chemical and Environmental EngineeringUniversity of GenoaItalyVia Montallegro 116145 GenoaItaly

Background:During eye rotations the vitreous humour moves with respect to the eye *** relative motion has been suggested to possibly have an important role in inducing degradation of the gel structure,which might lead to vitreous liquefaction and/or posterior vitreous *** of the present work is to study the characteristics of vitreous motion induced by eye ***:We use an experimental setup,consisting of a perspex model of the vitreous chamber that,for simplicity,is taken to have a spherical *** model is filled with an artificial vitreous humour,prepared as a solution of agar powder and hyaluronic acid sodium salt in deionised water,which has viscoelastic mechanical properties similar to those of the real *** model rotates about an axis passing through the centre of the sphere and velocity measurements are taken on the equatorial plane orthogonal to the axis of rotation,using an optical ***:The results show that fluid viscoelasticity has a strong influence on flow *** particular,at certain frequencies of oscillation of the eye model,fluid motion can be resonantly *** means that fluid velocity within the domain can be significantly larger than that of the ***:The frequencies for which resonant excitation occurs are within the range of possible eye rotations ***,the present results suggest that resonant excitation of vitreous motion is likely to occur in ***,in turn,implies that eye rotations produce large stresses on the retina and within the vitreous that may contribute to the disruption of the vitreous gel *** present results also have implications for the choice of the ideal properties for vitreous substitute fluids.

关键词： Vitreous motion Vitreous dynamics Retinal detachment Viscoelasticity

Population structure and range expansion:the case of the invasive gastropod Cyclope neritea in northwest Iberian peninsula

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Integrative Zoology 2012年第3期7卷 286-298页

作者： Lucía COUCEIRO Lúa LÓpeZ JoséMiguel RUIZ rodolfo BARREIRO Department of Ecology College of ScienceUniversity of A CoruñaA CoruñaSpain

Biotic invasions have a reputation for unpredictable ***,we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the *** neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic:the northwest Iberian peninsula(NWIP)and the French Atlantic coast(FAC).Shellfish seabed farming is intense in both areas but focuses on different commercial *** mitochondrial gene sequences,the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the *** FAC,genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of *** at each site rather than with geographical *** this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave,a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent *** jump dispersal pattern of *** in the NWIP,together with the observation that populations established in the same year are genetically undifferentiated,point to human transport as the most plausible explanation for the current range *** evidence for human-mediated dispersal,*** managed to develop a seemingly non-random genetic pattern in the *** is suggested that caution must be exerted when interpreting genetic patterns in invaders.

关键词： alien species Cyclope neritea cytochrome oxidase I genetic geographic pattern population structure

A Review on the Mechanical Behaviour of Bamboo Reinforced Concrete Beams

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Journal of Renewable Materials 2022年第12期10卷 3629-3657页

作者： Usama Sayed Assima Dauletbek Xue Xin rodolfo Lorenzo Haitao Li College of Civil Engineering Nanjing Forestry UniversityNanjing 210037China Joint International Research Laboratory for Bio-composite Building Materials and Structures Nanjing Forestry UniversityNanjing210037China University College London LondonWC1E 6BTUK

In light of the increasing demand for sustainable building materials,the effectiveness of bamboo utilization in various fields has become the object of scientists'close *** increased interest in bamboo is explained by its sustainable characteristics,which make it the most preferred material for environmentally friendly and cost-effective construction compared to conventional *** of bamboo is vast and diverse:from decora-tion and furniture to structural members and re *** to the low price,rich resources,and high ela sticity,bamboo culms have also been used as an alternative to steel reinforcement in concrete ***-sive research has been done to assess feasibilty of bamboo reinforcement in structural elements made of *** article discusses the mechanical properties of three types of structural bamboo reinforced concrete(BRC)*** original papers on the mechanical behaviour of structural BRC members were studied,and the fundamental properties induding typical failure modes,reasons of failure,load displacement relationships,and influencing factors were discussed and *** and conclusions of the review will contribute to deep understanding of structural feasibility of BRC beams and serve as a base for future research.

关键词： Concrete bamboo bamboo reinforced concrete mechanical behaviour

Value Creation in EMEA Demergers ——An Empirical Evidence

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Value Creation in EMEA Demergers ——An Empirical Evidence

作者： rodolfo GUARINO 复旦大学

学位级别：硕士

在美国,“企业分立”通常指一个集团分离成两个或两个以上的独立实体,并按照母公司的股东持股比例将股份分配给原有股东。企业分立通常有两种方式,一种是以股利形式发放剥离出来的实体的股票;另外一种则是解散母公司,直接将股票发放给... 详细信息

在美国,“企业分立”通常指一个集团分离成两个或两个以上的独立实体,并按照母公司的股东持股比例将股份分配给原有股东。企业分立通常有两种方式,一种是以股利形式发放剥离出来的实体的股票;另外一种则是解散母公司,直接将股票发放给股东。历史上大部分的企业分立发生在美国,但近年来在欧洲市场上也有很大幅度的增加。据统计,在2000年至2011年间,欧洲、中东和非洲地区一共有90多起交易,例如菲亚特和菲亚特工业、PostNL/TNT和Carphone Warehouse/Talk Talk。目前关于企业分立后短期和长期表现的实证文献主要是研究美国企业的经验,只有少数的文献研究欧洲的经验(据我所知只有Kirchmaier在2003年的研究,Veldt和Veld-Merkoulova在2004年-2006年的研究,以及Sudarsanam和Qian在2007年的研究)。这是由于与欧洲相比,美国企业分立有更悠久的历史和更高的频率。另外,欧洲国家不同的监管环境也是原因之一。本论文的目的是研究最近的欧洲,中东,非洲地区企业分立的浪潮(1998-2009),为这些日益流行的重组提供了一个全面和详尽的分析。在109个欧洲,中东和非洲地区交易的样本基础上,本文首先研究了企业分立后,母公司和剥离出来的实体的短期和长期的财富效应。研究发现短期内超额累计收益为正,而长期的超额累计收益却并不显着异于零。这一结果表明,欧洲,中东和非洲地区的合并企业分立,与美国企业分立不同,他们不具有与半强有效市场假设相符合的长期优异绩效。其次,本文研究了两种类型的企业分立对股东价值提高的差异：分立公司与母公司是不同行业的情况以及分立公司与母公司是同一行业的情况。研究发现前者优于后者,两个子样本有显著异于零的差异。这些结果与以往的对北美和欧洲市场的研究结果一致。最后,本文通过对企业分立归类来分析增值的不同来源：一类是“价值创造”,即经营业绩的改善;另一类是“价值认同”,即信息不对称的减少。研究发现只有分立公司与母公司是不同行业的时候才具有正面的“价值创造”,因此这种情况的超额累计收益比与分立公司与母公司是同一行业的表现要优异。而两个子样本都通过“价值认同”的机制都减少了信息不对称。

关键词：分立欧洲中东和非洲地区价值创造