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Simulation of temperature distribution and discharge crater of SiC_(p)/Al composites in a single-pulsed arc discharge

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Chinese Journal of Aeronautics 2021年第9期34卷 37-46页

作者： Jipeng CHEN Lin Gu Wansheng ZHAO mario GuAGLIANO School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering Politecnico Di MilanoPiazza Leonardo da Vinci32Italy

SiC_(p)/Al composites are difficult-to-cut *** recent years,electrical arc discharge machining has been developed to improve the machinability of these ***,there is a big challenge to build a satisfactory heat transfer model of SiC_(p)/Al composites in the arc *** is not only because of the material property difference between the reinforcement and matrix material but also because of the micro-dimension Si C *** paper established a new heat conduction simulation model considering the Si C particle-Al matrix interface and the phase change effects in a single-pulsed arc discharge of SiC_(p)/Al composites.A novel Si C particle-Al matrix cell geometric model was designed ***,the temperature distribution at a different depth from the workpiece surface was analyzed,the influence of sic volume fraction on temperature field was studied,and the contribution of the interface thermal resistance and latent heat were *** demonstrate the validity of the new numerical model,comparisons and verifications were ***,the method of improving the model was proposed and the machining mechanism of arc discharge of SiC_(p)/Al matrix materials was *** was found that high temperature is prone to concentrate on the surface layers of the workpiece especially when the Si C fraction is high,also,the temperature fluctuates respectively at the evaporation point of aluminum and Si C,and the Si C-Al resistance has less influence on temperature distribution compared to latent heat,*** model build in this work improves the simulation accuracy observably compared to the previous model,and the simulation work will help to acquire a detailed mechanism of material removal of SiC_(p)/Al composites in the arc discharge machining.

关键词： Arc discharge Discharge crater SiC_(p)/Al composites Single-pulsed Temperature distribution

Microscopic colitis: A therapeutic challenge

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World Journal of Gastroenterology 2013年第23期19卷 3531-3533页

作者： mario Guslandi Gastroenterology unit S. Raffaele University Hospital20132 Milan Italy

The treatment of microscopic colitis is mainly based on the use of budesonide, the only drug found effective in controlled clinical trials. After an initial course at a dose of 9 mg daily, however, most patients relapse when the drug is discontinued, hence a maintenance therapy at doses of 6 mg daily or lower is necessary. In order to avoid steroid dependence and drug toxicity different pharmacological agents should be considered as an alternative to indefinite long-term budesonide treatment. Evidence-based guidelines are currently lacking due to the lack of conclusive data concerning the use of either immunosuppressive or anti-tumor necrosis factor agents. For the time being in clinical practice the skilled physician should therefore tailor long term management of microscopic colitis on the single patient.

关键词： Microscopic colitis Budesonide Mesalazine Immunosuppressants

Niche segregation, competition, and urbanization

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Current Zoology 2018年第2期64卷 145-152页

作者： Anders PAPE MФLLER mario DiAz Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Pari-Saclay OrsayCedex F-91400 France Department of Biogeography and Global Change (BGC-MNCN-CSIC) NationalMuseum of Natural Sciences CSIC c/Serrano 155bis Madrid E-28006 Spain

urbanization of species is an ongoing process where successful urban colonizers usually obtain large fitness benefits. Mechanisms proposed to explain associations between urbanization and lifehistory traits are based on behavioral flexibility in food and habitat use and reduced fear responses. We test the novel hypothesis that interspecific competition for proximity to humans is driving ur- banization. We recorded the distance during the breeding season to human habitation for 50 pairs of closely related bird species, where one was closely associated with humans while the other species was not. The degree of urbanization was larger as was range size and abundance in the species more closely associated to humans. Flight initiation distance was shorter, and species closely associated with humans were more abundant in ancestral rural habitats. Likewise, species more closely associated with humans reproduced earlier and during longer periods. These results are consistent with the hypothesis that urbanization is promoted by interspecific competition. Resulting isolation by urban habitat may further facilitate contemporary adaptation to urban environments.

关键词： birds distance to human habitation isolation by habitat isolation by time mechanisms.

Changing Energy Consumption Behaviour: Individuals' Responsibility and Government Role

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Journal of Electronic Science and Technology 2015年第4期13卷 343-348页

作者： Mohamad Aldabas mario Gstrein Stephanie Teufel International Institute of Management in Technology (iimt) University of Fribourg

Renewable energy is clearly a very important topic nowadays. The risk and the damage that could be caused by conventional energy resources cannot be hidden. There is an enormous need that people start formulating a better attitude towards renewable energy and change their consumption behaviour. Otherwise, the future of environment and the coming generations is defiantly not going to be promising. This paper will discuss the importance of sustainable energy and how the energy related behaviour is created. It will present a framework to influence the current behaviour and push it to be more green oriented. It is also important to know till what limit are governments responsible in this change, and what are the tools that they have to push towards green direction.

关键词： Breaking bad habits green andrenewable energy energy consumption behavior.

Impact of Business Practices on Individual Energy Consumption

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Journal of Electronic Science and Technology 2015年第4期13卷 349-354页

作者： Stephane Egger mario Gstrein Stephanie Teufel International Institute of Management in Technology University of Fribourg

Changing behaviours and attitudes towards more sustainable individual energy consum- ption is a difficult topic to address. After identifying the most recurrent factors influencing bad energy consum- ption-society＇s environmental short- sightedness, a lack of individual responsibility and a tendency to put responsibility upon firms, institutions, and governments, the authors evaluated the effect business practices can have on individual behaviour. By qualifying as highly credible sources of information, positioning themselves as examples to follow and providing its employees with the necessary smart, innovative technology, business communities can have a major impact on changing individual behaviours towards more sustainable energy consumption.

关键词： Business practices individualbehaviour sustainable energy consumption.

The Impact of Delay in Software-Defined Integrated Terrestrial-Satellite Networks

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China Communications 2018年第8期15卷 11-21页

作者： Luca Boero mario Marchese Fabio Patrone Department of Electrical Electronics and Telecommunication Engineering and Naval Architecture (DITEN) University of Genoa

Satellite communication networks have been evolving from standalone networks with ad-hoc infrastructures to possibly interconnected portions of a wider Future Internet architecture. Experts belonging to the fifth-generation(5 G) standardization committees are considering satellites as a technology to integrate in the 5 G environment. Software Defined Networking(SDN) is one of the paradigms of the next generation of mobile and fixed communications. It can be employed to perform different control functionalities, such as routing, because it allows traffic flow identification based on different parameters and traffic flow management in a centralized way. A centralized set of controllers makes the decisions and sends the corresponding forwarding rules for each traffic flow to the involved intermediate nodes that practically forward data up to the destination. The time to perform this process in integrated terrestrial-satellite networks could be not negligible due to satellite link delays. The aim of this paper is to introduce an SDN-based terrestrial satellite network architecture and to estimate the mean time to deliver the data of a new traffic flow from the source to the destination including the time required to transfer SDN control actions. The practical effect is to identify the maximum performance than can be expected.

关键词： Integrated terrestrial-satellite net-works software defined networking software defined satellite networks delay estimation

SHADOWING,EXPANSIVENESS AND SPECIFICATION FOR C^1-CONSERVATIVE SYSTEMS

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Acta Mathematica Scientia 2015年第3期35卷 583-600页

作者： mario BESSA Manseob LEE 文晓 universidade da Beira Interior Rua Marques d'Avila e Bolama Department of Mathematics Mokwon University The School of Mathematics and Systems Science Beihang University

We prove that a Cl-generic volume-preserving dynamical system （diffeomor- phism or flow） has the shadowing property or is expansive or has the weak specification property if and only if it is Anosov. Finally, as in [10, 27], we prove that the Cl-robustness, within the volume-preserving context, of the expansiveness property and the weak specifica- tion property, imply that the dynamical system （diffeomorphism or flow） is Anosov.

关键词： Shadowing expansiveness specification generic Anosov volume-preserving star systems

Nanoparticle type effects on flexural, interfacial and vibration properties of GFRE composites

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Chinese Journal of Aeronautics 2016年第2期29卷 520-533页

作者： u.A.Khashaba Mechanical Engineering Department Faculty of Engineering King Abdulaziz University

Damping improvement in composite structures via introducing nanofillers generally has remarkable negative effects on the other mechanical properties. Therefore, in the present work, SiC and A1203 nanoparticles＇ infusion effects on the flexural, interracial and vibration properties of epoxy matrix and glass fiber reinforced epoxy （GFR/E） laminates were investigated. unidirectional （uD-GFR/E） and quasi-isotropic （QI-GFR/E） laminates with [0/± 45/90]s and [90/±45/0]s stack- ing sequences were hybridized by the optimum nanoparticles percentages. Results from off-axis flexural strengths of uD-GFR/E demonstrate good fiber/nanophased-matrix interracial bonding. The interlaminar shear stress between the adjacent layers with different orientations/strains of duc- tile QI-GFR/SiC/E laminates results in decreasing the flexural strengths respectively by 24.3% and 9.1% for [0/±45/90]s and [90/± 45/0]s stacking sequences and increasing the dissipated interfacial friction energy and thus the damping by 105.7% and 26.1%. The damping of QI-GFR/E, QI-GFR/SiC/E and QI-GFR/AI203/E laminates with [90/± 45/0]s stacking sequence was increased by 111.4%, 29.7% and 32.9% respectively compared to [0/± 45/90]s stacking sequence.

关键词： Flexural properties GFRE composites Interracial bonding Nanoparticles Non-destructive vibrationtechnique

On Several New Hilbert-type Inequalities Involving Means Operators

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Acta Mathematica Sinica,English Series 2013年第8期29卷 1493-1514页

作者： Vandanjav ADIYASuREN Tserendorj BATBOLD mario KRNI Department of Mathematical Analysis National University of Mongolia Institute of Mathematics National University of Mongolia Faculty of Electrical Engineering and Computing University of Zagreb

In this paper, we establish several new Hilbert-type inequalities with a homogeneous kernel, involving arithmetic, geometric, and harmonic mean operators in both integral and discrete case. Such inequalities are derived by virtue of some recent results regarding general Hilbert-type inequalities and some well-known classical inequalities. We also prove that the constant factors appearing in established inequalities are the best possible. As an application, we consider some particular settings and compare our results with previously known from the literature.

关键词： Hilbert inequality Hilbert-type inequality Hardy inequality Carleman inequality Knopp inequality