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Smart superabsorbent alginate/carboxymethyl chitosan composite hydrogel beads as efficient biosorbents for methylene blue dye removal

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Journal of Materials Science & Technology 2023年第28期159卷 81-90页

作者： Zhen Zhang noureddine Abidi Lucian Lucia Department of Forest Biomaterials NC State UniversityRaleighNCUSA Fiber and Biopolymer Research Institute Department of Plant and Soil ScienceTexas Tech UniversityLubbockTXUSA Department of Chemistry NC State UniversityRaleighNCUSA

The presence of toxic dyes in the aqueous medium has threatened environmental safety, and thereby re- moving them from wastewater in an efficient way is highly desired. Herein, the efficient biosorbents were successfully fabricated via a facile physical gelation process of sodium alginate (SA) and carboxymethyl chitosan (CMCTS) in an acidic aqueous solution. The as-prepared hydrogel beads not only displayed water superabsorbent properties and pH-responsive swelling characters but also exhibited excellent methylene blue (MB) adsorption capacity removal efficiency with experimental maximum MB adsorption capacity of 2518 and 1005 mg g -1 , which are comparable with most reported lignocellulosic and alginate-based hydrogels. The MB adsorption process fitted well in different kinetic and isotherm models and became more heterogeneous in concentrated MB solutions as verified by principal component analysis results. The adsorption mechanism was proposed, and the high dye absorbency was attributed to the strong electro- static forces between adsorbents and adsorbates. Our current study provides a promising and sustainable composite hydrogels platform targeted to dye decontamination.

关键词： Hydrogel Dye adsorption Composites Superabsorbent Sodium alginate Carboxymethyl chitosan

Energetic Analysis and Working Fluids Selection for a New Power and Refrigeration Combined Ecological System

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Journal of Thermal Science 2022年第6期31卷 2032-2050页

作者： noureddine TOUJANI Nahla BOUAZIZ Lakder KAIROUANI Tunis El Manar University Energy and Environment Research UnitNational School of Engineers of Tunis1002Tunisia

The main purpose of this study is to analyze the performance of a new system that combines organic Rankine Cycle(ORC) and vapor compression refrigeration cycle(VCRC) for refrigeration and cogeneration. This system uses low-temperature heat sources such as solar energy, geothermal, industrial waste heat and biomass. The novelty of the proposed system manifests itself essentially in: the development of new ORC-VCRC combination architecture, lowering the ORC condensing temperature, the possibility of refrigeration production by the ORC upstream of the pumping phase, preheating of ORC using VCRC fluid and new configurations based on the integration of heat recovery systems to improve the overall system performance. The first part of this study presents the energetic analysis for the basic system using different working fluids and investigation of the operating parameters effect on the system performance(The system performance is described by the ORC thermal efficiency, the VCRC coefficient of performance and the system overall efficiency). Ten working fluids have been selected in order to provide the most adequate candidates for the proposed system. The results showed that the heating temperature and the cooling temperature have a significant effect on the system performance. The choice of fluid was also mentioned;the obtained results confirmed that the best combination for the basic system is R236fa-acetone. Four system configurations are developed and analyzed in the second part of the study. Also in the same part of the study, we will compare these configurations in terms of the performance rate retained. In the last part, we will make a comparison of this new system with another system.

关键词： combined cycle working fluids organic Rankine cycle vapor compression cycle

Influence of specimen-reconstituting method on the undrained response of loose granular soil under static loading

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Acta Mechanica Sinica 2011年第5期27卷 796-802页

作者： noureddine Della Ahmed Arab Mostefa Belkhatir Laboratory of Material Sciences and Environment Civil Engineering DepartmentUniversity of ChlefSendjas Street PO Box 151 Chlef 02000Algeria

This paper describes the results of an experimental study on the undrained shear behaviour of loose sand collected from the location close to the epicenter of the recent Chlef （Algeria） Earthquake （October 10,1980）.The study focuses on the effects of the mode of the soil deposition on the liquefaction resistance of the Chlef *** this purpose,the results of undrained monotonic triaxial compression tests performed on samples with initial density of 0.29 under initial confining pressures ranged from 50 kPa to 200 kPa are *** specimens were prepared by two depositional methods namely dry funnel pluviation and wet *** was found that there was a marked difference in the undrained behaviour of sand in terms of maximal deviatoric stress,peak strength,residual strength and excess pore water pressure,even though the density and stress conditions were *** conclusion was that the soil fabric was responsible for this *** results indicated also that at low confining pressures,the specimens reconstituted by the wet deposition method exhibited complete static liquefaction （zero effective confining pressure and zero stress difference）.

关键词： Liquefaction · Undrained · Dry funnel pluviation · Wet deposition · Residual strength

Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology

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Chinese Physics Letters 2016年第5期33卷 144-148页

作者： Sara Benchikh noureddine Mebarki Dalel Aberkane Laboratoire de Physique Mathematique et Subatomique Mentouri University

Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data.

关键词： of on in Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology is that for been FRW

Implementation of a Biometric Interface in Voice Controlled Wheelchairs

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Sound & Vibration 2020年第1期54卷 1-15页

作者： Lamia Bouafif noureddine Ellouze National Institute of Biomedical Studies of Tunis 1092TunisTunisia Image and Signal Processing Laboratory ENIT BP 37University of Tunis El Manar1064Tunisia

In order to assist physically handicapped persons in their movements,we developed an embedded isolated word speech recognition system(ASR)applied to voice control of smart ***,in spite of the existence in the industrial market of several kinds of electric wheelchairs,the problem remains the need to manually control this device by hand via joystick;which limits their use especially by people with severe ***,a significant number of disabled people cannot use a standard electric wheelchair or drive it with *** proposed solution is to use the voice to control and drive the wheelchair instead of classical *** intelligent chair is equipped with an obstacle detection system consisting of ultrasonic sensors,a moving navigation algorithm and a speech acquisition and recognition module for voice control embedded in a DSP *** ASR architecture consists of two main *** first one is the speech parameterization module(features extraction)and the second module is the classifier which identifies the speech and generates the control word to motors power *** training and recognition phases are based on Hidden Markov Models(HMM),K-means,Baum-Welch and Viterbi *** database consists of 39 isolated speaker words(13 words pronounced 3 times under different environments and conditions).The simulations are tested under Matlab environment and the real-time implementation is performed by C language with code composer studio embedded in a TMS 320 C6416 DSP *** results and experiments obtained gave promising recognition ratio and accuracy around 99%in clean ***,the system accuracy decreases considerably in noisy environments,especially for SNR values below 5 dB(in street:78%,in factory:52%).

关键词： Handicapped persons smart wheelchairs voice control speech recognition training and classification

Speech-Music-Noise Discrimination in Sound Indexing of Multimedia Documents

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Sound & Vibration 2018年第6期52卷 2-10页

作者： Lamia Bouafif noureddine Ellouze National Institute of Biomedical Studies of Tunis 1092TunisTunisia Image and Signal Processing Laboratory ENIT BP 37University of Tunis El Manar1064Tunisia

Sound indexing and segmentation of digital documentsespecially in the internet and digital libraries are very useful tosimplify and to accelerate the multimedia document retrieval. Wecan imagine that we can extract multimedia files not only bykeywords but also by speech semantic contents. The maindifficulty of this operation is the parameterization and modellingof the sound track and the discrimination of the speech, musicand noise segments. In this paper, we will present aSpeech/Music/Noise indexing interface designed for audiodiscrimination in multimedia documents. The program uses astatistical method based on ANN and HMM classifiers. After preemphasisand segmentation, the audio segments are analysed bythe cepstral acoustic analysis method. The developed system wasevaluated on a database constituted of music songs with Arabicspeech segments under several noisy environments.

关键词： Speech processing audio indexing training andrecognition

Colorectal cancer screening: An updated review of the available options

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World Journal of Gastroenterology 2017年第28期23卷 5086-5096页

作者： Iyad A Issa Malak noureddine Department of Gastroenterology and Hepatology Rafik Hariri University Hospital

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including “westernized” diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon®) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program.

关键词： Colorectal cancer Colonoscopy Occult blood Fecal DNA test Blood DNA test Screening Guidelines

Genetic Programming-based Self-reconfiguration Planning for Metamorphic Robot

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International Journal of Automation and computing 2018年第4期15卷 431-442页

作者： Tarek Ababsa noureddine Djedi Yves Duthen LESIA Laboratory University of BiskraPO Box 145 RPBiskra 07000Algerla IRIT Laboratory University of Toulouse 1 Capitole21 Alles de BrinneToulouse 31032France

This paper presents a genetic programming based reconfiguration planner for metamorphic modular robots. Initially used for evolving computer programs that can solve simple problems, genetic programming （GP） has been recently used to handle various kinds of problems in the area of complex systems. This paper details how genetic programming can be used as an automatic programming tool for handling reconfiguration-planning problem. To do so, the GP evolves sequences of basic operations which are required for transforming the robot＇s geometric structure from its initial configuration into the target one while the total number of modules and their connectedness are preserved. The proposed planner is intended for both Crystalline and TeleCube modules which are achieved by cubical compressible units. The target pattern of the modular robot is expressed in quantitative terms of morphogens diffused on the environment. Our work presents a solution for self recontlguration problem with restricted and unrestricted free space available to the robot during reconfiguration, The planner outputs a near optimal explicit sequence of low-level actions that allows modules to move relative to each other in order to form the desired shape.

关键词： Modular robots unit-compressible modules self-reconfiguration genetic programming reconfiguration planning.

Prediction of the theoretical and semi-empirical model of ambient temperature

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Frontiers in Energy 2016年第3期10卷 268-276页

作者： Foued CHABANE noureddine MOUMMI Abdelhafid BRIMA Abdelhafid MOUMMI Mechanical Department Mechanical Engineering Laboratory (LGM)Faculty of Technology University of Biskra Biskra 07000 Algeria

It is well known that the ambient temperature is a sensitive parameter which has a great effect on biology, technology, geology and even on human behavior. A prediction is a statement about an uncertain event. It is often, but not always, based upon experience or knowl- edge. Although guaranteed accurate information about the future is in many cases impossible, prediction can be useful to assist in making plans about possible developments. As a result, temperature profiles can be developed which accurately represent the expected ambient temperature exposure that this environment experiences during mea- surement. The ambient temperature over time is modeled based on the previous Train and Tmax data and using a Lagrange interpolation. To observe the comprehensive variation of ambient temperature the profile must be determined numerically. The model proposed in this paper can provide an acceptable way to measure the change in ambient temperature.

关键词： ambient temperature environment correlation theoretical model semi-empirical