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Toward a nonlinear control of an AC-DC-PWM converter dedicated to induction heating

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Frontiers in Energy 2013年第2期7卷 140-145页

作者： Amel HADRI-HAMIDA S. ZEROUALI A. ALLAG Department of Electrical Engineering LEC Laboratory ConstantineUniversity Constantine 25000 Algeria Department of Electrical Engineering LMSE Laboratory BiskraUniversity Biskra 07000 Algeria

In this paper, a applied to an AC-DC-pulse nonlinear control strategy width modulation （PWM） converter is developed and simulated. First a nonlinear system modeling is derived with state variables of the input current and the output voltage by using power balance of the input and output. The system is linearized and decoupled, and then a state feedback law is obtained. For robust control of parameter perturbation, integrators are added to the exact feedback control law. The simulation is provided to verify the validity of the control algorithm.

关键词： DC-DC converter AC-DC-pulse width mod-ulation (PWM) converter induction heating nonlinearcontrol

Influence and Dispersion of Nanofiber of Wood Modified on Properties of Cement Based Mortars

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Journal of Renewable Materials 2019年第7期7卷 631-641页

作者： Fadhel Aloulou Alila Sabrine Habib Sammouda LabEM-LR11ES34:laboratory of Energy and Materials University of SousseTunisia lmse:Laboratoire Sciences des Matériaux et Environnement University of SfaxTunisia

Wood nanofibers from industrial waste have been used as polymeric material to reinforce the cement paste to a content of up to 2%by weight of *** effect of the wood nanofibre content on the porosity,the compressive strength and the degree of hydration of the cement was *** results showed an improvement in compressive strength of over 50%with 1%of added *** modification of nanofiber wood by grafting alkyl chains to their surface can reduce the amount of water absorbed by the *** of an anionic additive(SDBS)to the mixing water improves the surface of the samples more and more by minimizing the pore size by emulsion effect,hence the water absorption *** degree of hydration of the cement increased with the cellulose content containing *** analysis revealed that the presence of nanofibers favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.

关键词： Cement nano-fiber wood modified adjuvant,surfactant emulsion

Experimental study on the effects of big particles physical characteristics on the hydraulic transport inside a horizontal pipe

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Chinese Journal of Chemical Engineering 2016年第2期24卷 317-322页

作者： Salah Zouaoui Hassane Djebouri Kamal Mohammedi Sofiane Khelladi Aomar Ait Aidelr lmse laboratory Mouloud Mammeri University of Tizi-OuzouP.O.Box 17 RPI 5000Algeria LEMI laboratory MESO M'Hamed Bougara University of Boumerdes35000Algeria DynFluid laboratory Arts et Metiers Paris Tech151 boulevard de PHOpital75013 ParisFrance

This paper presents an experimental study of the physical characteristic effects of large particles on hydraulic transport in a horizontal *** particles are spherical and are large with respect to the diameter of the pipe(8%,10%,16% and 25%).Experiments were done to test the important parameters in solid transport(pressure,velocity,etc.).As a result,the relationship between the pressure gradient forces and the mixture velocity was substantially different from the pure liquid ***,in a single-phase flow a monotonous behavior of the pressure drop curve is observed,and the curve of the solid particle flow attains its minimum at the critical *** regimes are characterized with differential pressure measurements and visualizations.

关键词： Solid transport Two-phase flow Hydraulic gradient Flow regime

Stabilization and Evaluation of Modified Nanofiber Flour Wood on the Properties of Cement-Baszd Mortar

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Journal of Renewable Materials 2019年第8期7卷 763-774页

作者： Fadhel Aloulou Sabrine Alila Habib Sammouda laboratory of Energy and Materials(LabEM):LR11ES34 Higher School of Science and Technology of Hammam SousseUniversity of SousseSousseTunisia Laboratoire Sciences des Matériaux et Environnement:lmse Facultédes Sciences de SfaxUniversity of SfaxSfaxTunisia

The influence of nanofiberwood on the properties of the fresh condition of cement based mortars is not known in detail,despite recent advances in nanocellulose technology and it is related composite *** wood from industrial waste,produced by high-pressure homogenization,was used as cement partial replacement for cement paste at a content ranging from 0%to 2%by weight of *** effect of the nanofiber wood content on the porosity,the compressive strength and the degree of hydration of the cement was *** have shown an improvement in the compressive strength by more than 50%with 1%of added fiber *** chemical modification of nanofibers wood by grafting of chains alkyls in their surfaces can reduce the quantity of water absorbed by the *** addition of an anionic additive(SDBS)in the water of mixing improves of more the surface of samples by minimizing the size of pores by emulsion effect,from where the absorption of water *** degree of hydration of the cement has increased with the cellulose content containing *** analyze revealed that the presence of nanofiber wood favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.

关键词： Cement nano-fiber adjuvant surfactant emulsion hydratation thermal conductivity

Mathematical Model of Non-Coherent-DLL Discriminator Output and Multipath Envelope Error for BOC (α, β) Modulated Signals

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Positioning 2013年第1期4卷 65-79页

作者： Khaled Rouabah Chebir Saifeddine Salim Atia Mustapha Flissi Djamel Chikouche Electronics Department LMSE Laboratory University of Mohamed El-Bachir El-Ibrahimi Bordj Bou Arréridj Algeria Electronis Department LIS Laboratory University of M’sila M’sila Algeria

In this paper we propose the derivation of the expressions for the non-coherent Delay Locked Loop (DLL) Discriminator Curve (DC) in the absence and presence of Multipath (MP). Also derived, are the expressions of MP tracking errors in non-coherent configuration. The proposed models are valid for all Binary Offset Carrier (BOC) modulated signals in Global Navigation Satellite Systems (GNSS) such as Global Positioning System (GPS) and Future Galileo. The non-coherent configuration is used whenever the phase of the received signal cannot be estimated and thus cannot be demodulated. Therefore, the signal must be treated in a transposed band by the non-coherent DLL. The computer implementations show that the proposed models coincide with the numerical ones.

关键词： BOC Modulation GNSS PRN Code Multipath Discriminator Envelope Error

Study of the Mechanical Performance of a Recycled Aggregate Concrete with Admixture Addition

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Open Journal of Civil Engineering 2013年第2期3卷 99-103页

作者： Larbi Belagraa Miloud Beddar Department of Civil Engineering M’Sila University M’Sila Algeria laboratory of Materials and Electronic Systems (lmse) Faculty of Sciences and Technology Bordj Bou Arreridj University Bordj Bou Arreridj Algeria

The needs of the construction sector are still increasing for concrete. However the shortage of natural resources of aggregate could be a problem for the concrete industry. In addition, the negative impact on the environment is due to the construction demolition;where disposal wastes create a severe ecological and environmental hazard. In the last decade, a major interest has been developed for the reuse of recycled aggregates that present more than 70% of the concrete volume. The reused products should fulfill the requirements of lower cost and better quality, in order to establish its role in the concrete. The aim of this study is to assess the effect of the local admixtures on the mechanical behavior of recycled aggregate concrete (RAC). Physical and mechanical properties of RAC were investigated including density, compressive and flexural strength. The non-destructive test methods (NDT: pulse-velocity and rebound hammer) were used to determine the concrete strength. The results obtained were compared with crushed aggregate concrete (CAC) using the normal compressive testing machine test method. Thus, the convenience of indirect tests in the case of a recycled aggregate concrete were demonstrated.

关键词： Recycled Concrete Aggregate Demolition Waste Non-Destructive Tests Mechanical Strength Admixture

Study of interfaces of a one-way composite material in inflection

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材料科学与工程（中英文版） 2009年第3期3卷 8-15页

作者： Arezki Djebbar Micelle Salvia Leo. Vincent laboratory of Mechanics Structure Energy （LMSE） Faculte of the Genius of Construction Mechanical Department of Engineering University Tizi-Ouzou Algeria Department LTDS Central School of Lyon 36 avenue Guy de Collongue Lyon France

Effects of Cationic Surfactant on Fresh and Hardened Properties of Cement-Based Mortar

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Journal of Renewable Materials 2023年第5期11卷 2345-2365页

作者： Soumaya Zormati Fadhel Aloulou Habib Sammouda laboratory of Energy and Materials LabEM-LR11ES34University of SousseSousseTunisia

The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an admixture in cement *** examined composite properties as porosity,compression energy,thermal conductivity and *** results showed that with the addition of 0.7%by weight of NFC per emulsion in the presence of a cationic surfactant(CTAB).The new material produced presented a dry porosity between 4.7%and 4.4%,compressive strength between 9.8 and 22.9 MPa,and thermal conductivity between 0.95 and 2.25 W·m^(−1)·K^(−1).Thus we show better mechanical and thermal performance than that traditional Portland cement mortar with a density *** addition,the mortar made by emulsion of ordinary portland cement,cellulose nanofiber and organophilic clay(OC)treated with cetyltrimethylammonium bromide(CTAB)obtained has good resistance under high temperature and water,as well as excellent thermal insulation performance under high temperature and humidity *** study verified that the presence of NFC promotes hydration,leading to the production of more calcium silicate and portlandite gel.

关键词： Cement nanofiber cellulose organophile-clay thermal conductivity hydration surfactant compressive strength mortar

Bio-PCM Panels Composed of Renewable Materials Interact with Solar Heating Systems for Building Thermal Insulation

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Journal of Renewable Materials 2024年第4期12卷 771-798页

作者： Yosr Laatiri Habib Sammouda Fadhel Aloulou laboratory of Energy and Materials:LabEM-LR11ES34 University of SousseHammam SousseTunisia

This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential *** contribution is the creation of insulating composite panels made of bio-based phase change materials(bio-PCM is all from coconut oil),cement and renewable materials(treated wood fiber and organic clay).The inclusion of wood fibers improved the thermal properties;a simple 2%increase of wood fiber decreased the heat conductivity by approximately 23.42%.The issues of bio-PCM leakage in the cement mortar and a roughly 56.5%reduction in thermal conductivity with bio-PCM stability in composite panels can be resolved by treating wood fibers with an adjuvant by impregnating them in bio-PCM in the presence of the treated clay *** and wood fiber were treated with adjuvants that are both biological and environmentally acceptable,as confirmed by FTIR *** heat transfer bench(DIDATEK)showed a decrease in thermal *** using differential scanning calorimetric(DSC)analysis,the investigation of thermal stability and enthalpy during two heating cycles of pure bio-PCM and composite bio-PCM was *** novel renewable material was used to create composite panels for the trial prototype,which took the shape of a component attached to the solar heating system,33.57%less heat was lost,according to the heat transfer *** outcomes demonstrated the possibility of replacing traditional electric water heating in residential buildings with solar water heating systems.

关键词： Cement wood fiber PCM thermal conductivity thermal insulation solar energy