检索结果-南通市图书馆

MOdeLING AND OPTIMIZATION OF CYCLIC HOIST SCHEDULES IN AN ELECTROPLATING LINE

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2016年第4期25卷 469-490页

作者： Ahmed Nait-Sidi-Moh Adnen EI-Amraoui Universite de Picardie Jules Verne Laboratoire des Technologies lnnovantes 02100 ST Quentin France Universite d'Orleans Laboratoire PRISME 63 av. de Lattre de Tassigny 18020 Bourges France

This paper deals with the modeling, analysis and optimization of a specific kind of real industrial problems. This class of problems is known in the literature as Cyclic Hoist Scheduling Problem （CHSP）. In such class of problems, several jobs have to flow through a production line according to an ordered bath sequence. The CHSPs appear in the manufacturing facilities to achieve a mass production and to search a repetitive sequence of moves for the hoist. In this paper, we develop P-Temporal Petri Net models to represent the behavior and validate certain qualitative properties of the basic production line. Afterward, complex configurations of the production line are modeled and their properties such as reachability of desired functioning （cyclic operation）, deadlock-free, resource sharing and management are checked and validated. A mathematical analysis and a simulation study of all proposed Petri net models are carried out using mathematical fundaments of Petri nets and a Visual Object Net ＋＋ tool. The second part of the paper deals with the development of a mixed integer linear programming models to optimize processing of each line configuration. Optimal manufacturing plans of the studied system with cyclic processing sequences are defined and the feasibility of optimal cyclic scheduling of each configuration is proved.

关键词： Manufacturing lines processing tanks cyclic scheduling Petri nets mixed integer linear programming modeling optimization

THE MEANING OF FROZEN TOKENS IN LIVE NETS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China mathematics 1989年第4期32卷 459-469页

作者：陆维明 A.MERCERON Institute of mathematics Academia SinicaBeijing laboratoire de Recherche en Informatique University Paris-sud91405 Orsay CedexFrance

A concurrent system can be modeled by a Petri net. A live Petri net may have fro-zen tokens. It is showed that such tokens can be deleted if they are superfluous, and, whilethey are useful, can be defrozen if they bec... 详细信息

关键词： frozen token live net unfair occurrence.

Small dissymmetry, yet large effects on the transport propertiesof electrolytes based on imide salts: Consequences on performancein Li-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第2期31卷 352-366页

作者： Joseph Chidiac Laure Timperman Mérièm Anouti laboratoire PCM2E Universitéde ToursParc de Grandmont37200 ToursFrance

To gain better insight into the influence of the anion size and symmetry on the transport properties and thermal stability of an electrolyte based on lithium(fluorosulfonyl)(trifluoromethanesulfonyl)-imide(FTFSI)salt,we performed the physical and electrochemical characterization of an electrolyte based on FTFSI incorporated in standard binary(3 EC/7 EMC)and ternary(EC/PC/3 DMC)alkylcarbonate *** applying the Jones-Dole-Kaminsky(JDK),Eyring and Arrhenius empirical models to the electrolyte viscosity we show that the activation enthalpy and entropy energy barriers(ΔH≠,ΔS≠)for viscous flow are between 12 and 15 kJ·mol^(-1).They are strongly dependent on the solvent nature and are significantly lower than their symmetric anions LiFSI and LiTFSI(19-20 kJ·mol^(-1))in the binary ***,the hydrodynamic radius,rs,calculated by JDK,and the ionicity behavior illustrated by the Walden role,showed that the FTFSI anion is outside the solvation sphere(rs>0.6 nm)which is smaller in the case of an EC/EMC solvent *** the 3 EC/7 EMC solvent mixture,LiFTFSI is less conductive than in the ternary mixture i.e.,σ_(max)=8.9 mS cm^(-1) at C_(max)=1.1 mol L^(-1) for 3 EC/7 EMC and,σ_(max)=10.5 mS cm^(-1) at max=0.7 mol L^(-1) for EC/PC/3 DMC,due to a strong solvation and a greater association of FTFSI ions in the binary solvent *** thermal stability of FTFSI based electrolytes was determined by the shift of the evaporation temperature of the volatile solvents(DMC,EMC)in the presence of salt,towards the higher *** feature is visible on the thermograms obtained by DSC both with the liquid electrolyte and with charged LMO cathodes in presence of *** consequences of these properties on the electrochemical behavior of a graphite(Gr)half-cell,a lithium metal(Li)anode and a manganese lithium oxide(LMO)cathode demonstrated on the one hand the formation of a thick solid electrolyte interphase(SEI)on graphite that consumed a significant amou

关键词： LiFTFSI Electrolyte Viscosity Interface Li-ion battery

3D Modeling of sediment movement by ships-generated wakes in confined shipping channel

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2014年第1期29卷 49-58页

作者： Shengcheng JI Abdellatif OUAHSINE Hassan SMAOUI Philippe SERGENT Université de Technologie de Compiègne Laboratoire RobervalUMR CNRS 7337Centre de recherche Royallieu Université de Technologie de Compiègne LHN(CETMEF)/Laboratoire Roberval UMR CNRS 7337Centre de recherche Royallieu

Ship-generated waves and return currents are capable of re-suspending significant quantities of bottom and bank ***,most of the previous studies done on the subject do not show how and where sediment is re-suspended by the wakes and the directions of net *** this paper,a 3D numerical model based on hydro-sedimentary coupling is presented to search the relationship between the sediment movement,and the pattern of ship-generated waves around and far away from the vessel and the return currents around the *** hydrodynamic model is based on 3D Navier-Stokes equations including the standard k-ε model for turbulence processes,and the sediment transport model is based on a 3D equation for the re-suspended sediment *** computation results show that the areas of sediment concentration and transport(whether by resuspension or by the bedload) depend mainly on the position,the speed of the ship in the waterways,the kinematics of ship-generated waves and on the return ***,a map of sediment distribution and the modes of sediment transport generated by the passage of the ship are presented.

关键词： Sediment transport Waterway Ship waves CFD

The Quantum Trihedron

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2016年第11期33卷 28-30页

作者： A.Bendjoudi N.Mebarki laboratoire de Physique Mathematique et Subatomique Freres Mentouri University

The convex hull on three points in two-dimensional Euclidean space of three flat edges （trihedron） is studied. The Bohr-Sommerfeld quantization of the area of space is performed. It is shown that it reproduces exact... 详细信息

关键词： of in that is

Hemodynamic and antifibrotic effects of a selective liver nitric oxide donor V-PYRRO/NO in bile duct ligated rats

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2006年第41期12卷 6639-6645页

作者： Frédéric Moal Nary Veal Eric Vuillemin Eric Barrière Jianhua Wang Lionel Fizanne Frédéric Oberti Olivier Douay Yves Gallois Dominique Bonnefont-Rousselot Marie Christine Rousselet Paul Calès laboratoire HIFIH UPRES 3859 Université Angers France laboratoire de Biochimie Université Angers France INSERM U481 Hopital Beaujon Clichy France laboratoire de Biochimie Hopital de 1a Salpêtrière Paris France

AIM: To assess whether a liver specific nitric oxide (NO) donor (V-PYRRO/NO) would prevent the development of portal hypertension and liver fibrosis in rats with bile duct ligation (BDL). METHODS: Treatment (placebo or V-PYRRO/NO 0.53 μmol/kg per hour) was administered i.v. to rats 2 d before BDL (D-2) and maintained until the day of hemodynamic measurement (D26). Intra-hepatic NO level was estimated by measuring liver cGMP level. Effects of V-PYRRO/NO on liver fibrosis and lipid peroxidation were also assessed. RESULTS: Compared to placebo treatment, V-PYRRO/ NO improved splanchnic hemodynamics in BDL rats: portal pressure was significantly reduced by 27% (P development was almost completely blocked (splenorenal shunt blood flow by 74%, P = 0.007). Moreover, V-PYRRO/NO significantly prevented liver fibrosis development in BDL rats (by 30% in hepatic hydroxyproline content and 31% in the area of fibrosis, P decrease in lipid peroxidation by 44% in the hepatic malondialdehyde level (P = 0.007). Interestingly, we observed a significant and expected increase in liver cGMP, without any systemic hemodynamic effects (mean arterial pressure, vascular systemic resistance and cardiac output) in both sham- operated and BDL rats treated with V-PYRRO/NO. This result is in accordance with studies on V-PYRRO/NO metabolism showing a specific release of NO in the *** in BDL rats improved liver fibrosis and splanchnic hemodynamics without any noxious systemic hemo- dynamic effects.

关键词： Nitric oxide Portal hypertension Liver fibrosis Hemodynamics Rats

Doppler Global Velocimeter-development and Validation with Measurements in a Round Free Jet

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2009年第1期18卷 74-84页

作者： X.Ottavy S.Goguey J.Berthiau I.Trébinjac laboratoire de Mécanique des Fluides et d’Acoustique(LMFA)

Doppler global velocimetry （DGV） has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave （CW） argon ion laser for ermssion, lne receiver Ieatures only one camera for both signal and reference images and incorporates a deF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.

关键词： laser anemometry Doppler shift iodine vapor absorption line filter deFI system image processing.

Properties of n-type SnO_2 semiconductor prepared by spray ultrasonic technique for photovoltaic applications

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第12期36卷 34-37页

作者： H.Bendjedidi A.Attaf H.Saidi M.S.Aida S.Semmari A.Bouhdjar Y.Benkhetta laboratoire de Physique des Couches Minces et Applications Université de Biskra laboratoire des Couches minces et Interfaces Université Mentouri

Transparent conducting n-type SnO2 semiconductor films were fabricated by employing an inexpensive, simplified spray ultrasonic technique using an ultrasonic generator at deferent substrate temperatures （300, 350, 400, 450 and 500 ℃）. The structural studies reveal that the SnO2 films are polycrystalline at 350,400, 450, 500 ℃ with preferential orientation along the （200） and （101） planes, and amorphous at 300 ℃. The crystallite size of the films was found to be in the range of 20.9-72.2 nm. The optical transmittance in the visible range and the optical band gap are 80% and 3.9 eV respectively. The films thicknesses were varied between 466 and 1840 nm. The resistivity was found between 1.6 and 4 × 10^-2 Ω.cm. This simplified ultrasonic spray technique may be considered as a promising alternative to a conventional spray for the massive production of economic SnO2 films for solar cells, sensors and opto-electronic applications.

关键词： tin oxide thin films spray ultrasonic structural properties optical properties

Some Uniqueness Results for Functional Damped Semilinear Differential Equations in Fréchet Spaces

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2008年第1期24卷 95-106页

作者： Abdelghani OUAHAB laboratoire de Mathématiques Universitéde Sidi Bel Abbès BP 89

A recent nonlinear alternative for contraction maps in Frechet spaces due to Frigon and Granas （Resultats de type Leray-Schauder pour des contractions sur des espaces de Frechet, Ann. Sci. Math. Quebec 22, （2）, 161-168 （1998））, combined with semigroup theory, is used to investigate the existence and uniqueness of mild solutions for first- and second-order functional semi linear and neutral damped differential equations in Frechet space.

关键词： differential equations damped semigroup family cosinus mild solution fixed point uniqueness Frechet spaces contraction