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The high level language for system specification: A model-driven approach to systems engineering

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维普期刊数据库

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第1期7卷 180-214页

作者： Hamzat Olanrewaju Aliyu Oumar Maıga Mamadou Kaba Traore School of Information and Communication Technology Federal university of Technology Minna Gidan-Kwanu Campus MinnaNigeria universit´e des sciences des techniques et des technologies BamakoMali LIMOS CNRS UMR 6158 universite Blaise Pascal Clermont-FerrandFrance

We present HiLLS(High Level Language for System Specification),a graphical formalism that allows to specify Discrete event System(des)models for analysis using methodologies like simulation,formal methods and ***’syntax is built from the integration of concepts from System Theory and Software engineering aided by simple concrete notations to describe the structural and behavioral aspects of *** paper provides the syntax of HiLLS and its simulation semantics which is based on the Discrete event System Specification(DeVS)*** DeVS-based Modeling and Simulation(M&S)perspective,HiLLS is a platform-independent visual language with generic expressions that can serve as a front-end for most existing DeVS-based simulation environments with the aid of Model-Driven engineering(MDe)*** also suggests ways to fill some gaps in existing DeVS-based visual formalisms that inhibit complete specification of the behavior of complex *** provide a case study to illustrate the core features of the language.

关键词： HiLLS modeling and simulation integrated formalism DeVS Object-Z

A Review on Conductive and Transparent Materials Used in the design of Transparent Antennas

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Open Journal of Antennas and Propagation 2023年第2期11卷 11-25页

作者： Abdoulaye Sissoko Cheick Oumar Sanogo Badié Diourté université des sciences des techniques et des technologies de bamako Bamako Mali

In this review, we highlight the essential parameters of some transparent materials for use in the design of transparent antennas. ITO films with a sheet resistance of Rs = 10 Ω/sq and a T = 90% transmittance, we turn to materials that can be serious alternatives for ITO, such as graphene T = 97% for Rs = 60 Ω/sq and the micro-mesh metal. Wire mesh seems to be the best alternative T = 93% for Rs Rs = 0.022 Ω/sq at T = 81%, this is the micrometric pitch mesh.

关键词： Transmittance Resistance by Square Grid Micrometric Mesh

effect of some parameters on the performance of anchor impellers for stirring shear-thinning fluids in a cylindrical vessel

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Journal of Hydrodynamics 2016年第4期28卷 669-675页

作者： Houari AMeUR Institut des sciences et technologies Centre Universitaire Salhi Ahmed

The 3-D hydrodynamics of shear thinning fluids in a stirred tank with an anchor impeller were numerically *** using a computational fluid dynamics code（CFX 13.0）,the obtained results give a good prediction of the hydrodynamics such as the velocity fields and cavern *** multiple reference frames（MRF） technique was employed to model the rotation of the *** rheology of the fluid was approximated using the Ostwald *** validate the CFD model,some predicted results were compared with the experimental data and a satisfactory agreement was *** effects of impeller speed,fluid rheology,and some design parameters on the flow pattern,cavern size and power consumption were explored.

关键词： anchor thinning satisfactory rotation frames rheology validate hydrodynamics stirring corner

Phosphorus mobility in dam reservoir affected by redox oscillations:An experimental study

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Journal of environmental sciences 2019年第3期31卷 250-263页

作者： Anne Rapin Malgorzata Grybos Marion Rabiet Brice Mourier Véronique Deluchat université de Limoges PEIRENE EA 7500 Faculté des Sciences et Techniques université de Lyon UMR5023 Laboratoire d'ecologie des Hydrosystèmes Naturels et Anthropisés Université Lyon 1ENTPE CNRS

The internal sedimentary phosphorus(P) load of aquatic systems is able to support eutrophication, especially in dam–reservoir systems where sedimentary P stock is high and where temporary anaerobic conditions occur. The aim of this study therefore is to examine the response of sedimentary P exposed to redox oscillations. Surface sediments collected in the Champsanglard dam–reservoir(on the Creuse River, France) were subjected to two aerobic phases(10 and 12 days) alternated with two anaerobic periods(21 and 27 days)through batch incubations. The studied sediment contained 77 ± 3 μmol/g DW of P, mainly associated with the ascorbate fraction(amorphous Fe/Mn oxyhydroxides). The used sediment was rich in organic matter(OM)(21% ± 1%) with primarily allochthone *** results showed that redox oscillations enhance dissolved inorganic phosphorus release at sediment/water interface. During the first anaerobic stage, the P release was mainly controlled by the dissolution/precipitation of iron minerals. The more pronounced increase of P release during the second anaerobic stage(44%) was due to various mechanisms related to the change in quality of dissolved organic matter(DOM), namely a higher SUVA254 and humification indices. The release of more refractory DOM(rDOM) served to lower the microbial metabolism activity, possibly favored iron oxyhydroxide aggregation and thus limiting iron reduction. In addition, rDOM is able to compete for mineral P sorption sites,leading to a greater P release. In reservoir with predominant allochthone OM input, the release of more aromatic DOM therefore plays an important role in P mobility.

关键词： Phosphorus Sediment Redox Iron Organic matter

effect of fluorinated additives or co-solvent on performances of graphite//LiMn2O4 cells cycled at high potential

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Journal of energy Chemistry 2021年第1期30卷 332-342,I0011页

作者： Benjamin Flamme Darius JYeadon Satyajit Phadke Mérièm Anouti Laboratoire PCM2e EA 6299-Universitéde ToursFacultédes Sciences et TechniquesParc de Grandmont37200 ToursFrance

Herein,a comprehensive study of electrochemical performances of the combined effect of fluorinated additives;fluoroethylene carbonate(FeC);and tris(2,2,2-trifluoroethyl) phosphite(TTFP) or the 2,2,2-trifluoroethyl methyl carbonate(TFeMC) as co-solvent,on Graphite//LiMn2O4 cells cycled at high potential is *** one side,each additive has a specific function,the FeC is dedicated to the negative electrode and the TTFP to the opposite *** electrolyte mixture with(4% FeC+1% TTFP) additive has shown the best ability to reduce fading of the LiMn2O4 electrode,especially at high *** the other side,by studying the comparative thermal and transport properties of the formulated electrolytes with different proportions of TFeMC,we demonstrate that the difference in charge distribution of eMC and TFeMC molecules induced by the presence of fluorine atoms,modifies the solvation model of the Li+cation,and changes its behavior at the CeI interface and impact strongly the electrochemical ***,the eIS investigation of the LMO/electrolyte interfaces in the presence of TFeMC demonstrates that despite a spontaneous chemical reactivity of the TFeMC at the cathode interface over time,the conductive and good quality CeI is formed,which positively impact the *** study shows that against LMO surface phenomena,the combination in adequate proportions of fluorinated additives or solvent can be a solution not only to avoid the oxidative reactivity of LMO-cathode,but also to prevent its harmful consequences on the Li-metal or graphite-anode by controlling the solvation of lithium-ion.

关键词： Li-ion battery LMO-cathode Fluorinated-solvent Additive Fluoro-alkylcarbonate

3D hydrodynamics involving multiple eccentric impellers in unbaffled cylindrical tank

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Chinese Journal of Chemical engineering 2016年第5期24卷 572-580页

作者： Houari Ameur Institut des sciences et technologies Centre Universitaire Salhi Ahmed CUN-SA

In this paper, the numerical predictions of 3D hydrodynamics and power consumption in a vessel stirred by mul- tiple eccentrically located impellers are presented. The vessel is a fiat-bottomed cylindrical one equipped with six-curved bladed impellers. Aqueous solutions of xanthan gum are used, which have a shear thinning behavior with yield stress. The influence of several parameters on the mixing efficiency has been investigated, namely： the stirring rate, fluid theology, impeller number and impeller clearance from the tank bottom. Our predicted results are compared with other experimental data and a satisfactory agreement is found.

关键词： Computational fluid dynamics Mixing Non-Newtonian fluids Laminar flow eccentric impeller

Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques

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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINe Abdellatif NACeUR Hakim eL WASSIFI Karima Laboratoire Roberval Université de Technologie de Compiègne Laboratoire LAMIH Université de Valenciennes université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

The Consideration of Overlapping Lines in the Calculation of Radiative Power emitted from CH_4 Thermal Plasma

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Plasma Science and Technology 2012年第12期14卷 1073-1078页

作者： R. BeNALLAL B. LIANI Theoretical Physics Laboratory Abou Bekr Belkaid University cole prparatoire des sciences et techniques

Net emission coefficients of radiation were calculated for isothermal plasma of methane as a function of the plasma temperature 5,000 - 30,000 K and the arc radius 0 mm to 10 mm at atmospheric pressure. Calculations take into account continuum and line radiations, special attention has also been given to the influence of overlapping spectral lines. The line shapes in our calculations are given by convolution of Doppler and Lorentz profiles, resulting in a simplified Voigt profile. In the case of a hydrogen profile, we used the Vidal tables, and the four first Lyman lines and the four first Balmer lines were considered. This calculation was carried out on the assumption of local thermodynamic equilibrium and in a nondiffusive environment. The net emission coefficient calculation for pure argon plasma was compared with the experimental results of evans in our previous work. We used the escape factor, and our results were higher than those of the experiment. In this paper, we explain why, using the escape factor, the radiation is overestimated. The net emission coefficient obtained from a real spectrum was compared with essoltani work＇s which used the line-by-line method for pure argon plasma.

关键词： thermal plasma radiation net emission coefficient absorption coefficient

New Method for Injectable Quinine Quality Assurance Control Using a Multi-Spectral Microscope

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Optics and Photonics Journal 2018年第3期8卷 66-74页

作者： A. Sow I. Traore T. Diallo A. BA Laboratoire d’Optique de Spectroscopie et des Sciences Atmosphériques (LOSSA) Faculté des Sciences et Techniques (FST) Université des Sciences des Techniques et des Technologies de Bamako Bamako Mali Département des sciences du Médicament Faculté de Pharmacie Université des Sciences des Techniques et des Technologies de Bamako Bamako Mali Laboratoire National de la Santé (LNS) Bamako Mali

Africa is the world region that is most affected by malaria. Among the therapies used, injectable quinine is considered to be one of the effective antimalarial drug, however non-quality assured antimalarials clearly have a strong market penetration across Africa. To overcome this problem, it becomes more and more necessary to set up quantitative and qualitative analysis system for antimalarial quality control. The objective of the present investigation is an attempt to use customized multispectral microscope equipped with UV-Visible lasers for injectable quinine quality assurance control routinely. For that, we have established the calibration curve of quinine solution concentration as a function of area under light intensity histogram crossing the solution. From this calibration curve, we can check the conformity of any injectable quinine according to the pharmacopoeia involved. The proposed technique is a promising alternative for drug quality control routinely.

关键词： Injectable Quinine Area Under Curve Multispectral Microscope Absorbance