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Convergence Analysis of Iterative Threshold Decoding Process

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Journal of Computer and Communications 2016年第14期4卷 98-107页

作者： Mohammed Lahmer mostafa belkasmi Abdallah Rhattoy Department of Computer Science High School of Technologies Meknes Morocco Department of Network and Telecoms ENSIAS Rabat Morocco

Today the error correcting codes are present in all the telecom standards, in particular the low density parity check (LDPC) codes. The choice of a good code for a given network is essentially linked to the decoding performance obtained by the bit error rate (BER) curves. This approach requires a significant simulation time proportional to the length of the code, to overcome this problem Exit chart was introduced, as a fast technique to predict the performance of a particular class of codes called Turbo codes. In this paper, we success to apply Exit chart to analyze convergence behavior of iterative threshold decoding of one step majority logic decodable (OSMLD) codes. The iterative decoding process uses a soft-input soft-output threshold decoding algorithm as component decoder. Simulation results for iterative decoding of simple and concatenated codes transmitted over a Gaussian channel have shown that the thresholds obtained are a good indicator of the Bit Error Rate (BER) curves.

关键词： OSMLD EXIT BER Mutual Information Iterative Threshold Decoding Extrinsic Information LLR

Majority Voting Procedure Allowing Soft Decision Decoding of Linear Block Codes on Binary Channels

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International Journal of Communications, Network and System Sciences 2012年第9期5卷 557-568页

作者： Said Nouh Achraf El Khatabi mostafa belkasmi SIME Lab National School of Computer Science and Systems Analysis(ENSIAS)Mohammed V Souissi UniversityRabatMorocco

In this paper we present an efficient algorithm to decode linear block codes on binary channels. The main idea consists in using a vote procedure in order to elaborate artificial reliabilities of the binary received word and to present the obtained real vector r as inputs of a SIHO decoder (Soft In/Hard Out). The goal of the latter is to try to find the closest codeword to r in terms of the Euclidean distance. A comparison of the proposed algorithm over the AWGN channel with the Majority logic decoder, Berlekamp-Massey, Bit Flipping, Hartman-Rudolf algorithms and others show that it is more efficient in terms of performance. The complexity of the proposed decoder depends on the weight of the error to decode, on the code structure and also on the used SIHO decoder.

关键词： Error Correcting Codes Genetic Algorithms HIHO Decoder SIHO Decoder Vote Procedure

On the Computing of the Minimum Distance of Linear Block Codes by Heuristic Methods

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International Journal of Communications, Network and System Sciences 2012年第11期5卷 774-784页

作者： Mohamed Askali Ahmed Azouaoui Said Nouh mostafa belkasmi SIME Lab National School of Computer Science and Systems Analysis(ENSIAS)Mohammed V-Souisi UniversityRabatMorocco

The evaluation of the minimum distance of linear block codes remains an open problem in coding theory, and it is not easy to determine its true value by classical methods, for this reason the problem has been solved in the literature with heuristic techniques such as genetic algorithms and local search algorithms. In this paper we propose two approaches to attack the hardness of this problem. The first approach is based on genetic algorithms and it yield to good results comparing to another work based also on genetic algorithms. The second approach is based on a new randomized algorithm which we call 'Multiple Impulse Method (MIM)', where the principle is to search codewords locally around the all-zero codeword perturbed by a minimum level of noise, anticipating that the resultant nearest nonzero codewords will most likely contain the minimum Hamming-weight codeword whose Hamming weight is equal to the minimum distance of the linear code.

关键词： Minimum Distance Error Impulse Method Heuristic Methods Genetic Algorithms NP-Hardness Linear Error Correcting Codes BCH Codes QR Codes Double Circulant Codes

Viscoelastic potential flow instability theory of Rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： D.M.mostafa Department of Mathematics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynamic Kelvin-Helmholtz instability of the interface between two viscoelastic Rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of complex coefficients for asymmetric disturbance has been obtained by using normal mode *** stability criteria are analyzed theoretically and illustrated *** imaginary part of growth rate is plotted versus the wave *** influences of dynamic viscoelastic,uniform velocities,Reynolds number,electric field,dynamic viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： Rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynamics stability

Relative(n,k)-Weak Cotorsion Modules

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Algebra Colloquium 2024年第3期31卷 481-498页

作者： mostafa Amini Houda Amzil Driss Bennis Department of Mathematics Faculty of SciencesPayame Noor UniversityTehranIran Department of Mathematics Faculty of Sciences EI Jadida Chouaib Doukkali UniversityMorocco Department of Mathematics Faculty of Sciences Mohammed V University in RabatMorocco

Let R be a ring and n,k be two non-negative *** an extension of several known notions,we introduce and study(n,k)-weak cotorsion modules using the class of right R-modules with n-weak fat dimensions at most *** exampl... 详细信息

关键词： (n,k)-weak cotorsion module n-weak injective module n-weak fat module n-super finitely presented module

Experimental and numerical investigation of iron ore pellet firing using coupled CFD-DEM method

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Particuology 2024年第10期93卷 75-86页

作者： Hafez Amani Eskandar Keshavarz Alamdari mostafa Keshavarz Moraveji Bernhard Peters School of Material Engineering and Advanced Processes Amirkabir University of Technology(Tehran Polytechnic)424 Hafez AveTehran15875-4413Iran Facultédes Sciences de la Technologie et MédicineUniversity of LuxembourgCampus Kirchberg 6Rue Coudenhove-KalergiKirchberg L-1359Luxembourg

Iron ore pellets are the main feedstock in ironmaking processes. While extensive research has addressed numerical modeling of the iron ore pellet induration process, little effort has been made to describe the intricate thermochemical processes occurring within the reactor starting from the pellet and particularly at the intra-particle scale. In this regard, discrete-continuous methods like CFD-DEM can generate more realistic, irregular particle assemblies, which leads to significantly more accurate predictions of voidage variation, wall effects, temperature distribution, and associated mass transfer phenomena. This study presents a numerical model based on computational fluid dynamics (CFD) coupled with the discrete element method (DEM) to simulate the thermal induration process of iron ore pellets. The presented model solving heat, mass, and momentum conservation equations for both continuous and discrete phases, provides detailed information on the thermochemical aspects of the process. Pilot-scale induration experiment was conducted to validate model predictions in terms of thermal history and final conversion fraction. It was found that inlet charge specifications, such as particle and pellet size, significantly impact the productivity of pelletizing plants, highlighting the potential of the presented model to optimize the process and improve plant productivity.

关键词： CFD-DEM Heatandmass transfer Ironorepellets Powderand pelletsize Modeling

Enhancing sustainability in phosphate ore processing:Performance of frying oil as alternative flotation collector for carbonate removal

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International Journal of Mining Science and Technology 2024年第4期34卷 557-571页

作者： Asmae El-bahi Yassine Taha Yassine Ait-Khouia Abdellatif Elghali mostafa Benzaazoua Geology&Sustainable Mining Institute(GSMI) Mohammed VI Polytechnic UniversityBen Guerir 43150Morocco

Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste ***,it offers a cost-effective solution for crafting a specialized collector designed to efficiently remove carbonates and enhance phosphate enrichment in froth flotation *** study focuses on the synthesis of an anionic collector using the saponification reaction of a frying oil sample,subsequently applied to the flotation of calcite and *** elucidate the adsorption mechanisms of the frying oil collector(FrOC)and sodium oleate,a reference collector,on fluorapatite,calcite,dolomite,and quartz surfaces,comprehensive experiments were conducted,including zeta potential measurements and Fourier transform infrared *** revealed diverse adsorption affinities of the molecules towards these *** assess the practical performance of the collector,flotation tests were conducted using a natural phosphate ore mixture,employing a BoxBehnken experimental ***,under optimized conditions(pH 9,1000 g/t of FrOC,3.5 min of conditioning,and 6 min of flotation),FrOC exhibited excellent performance,with calcite and dolomite recoveries exceeding 80%,while apatite recovery in the concentrate fraction remained below 10%.This work exemplifies both circular economy practices and the distinctive approach to sustainable mineral processing.

关键词： Frying oils recycling Phosphate beneficiation Flotation separation Green surfactants Sustainability

Er_(2)TiO_(5)@Ag nanocomposites:Enhanced photocatalysis and bacteria inactivation,and cytotoxicity

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Journal of Rare Earths 2024年第5期42卷 851-858,I0002页

作者： Mehdi Nazeri Hossein Sedaghat Reza Rafiei Mohammad Amin Farzin Seyed mostafa Hosseinpour Mashkani Department of Parasitology and Mycology Kashan University of Medical SciencesKashanIran Department of Microbiology Kashan University of Medical SciencesKashanIran General Medicine Student School of MedicineKashan University of Medical SciencesKashanIran Student Research Committee Kashan University of Medical SciencesKashanIran Institute for Biomedical Materials and Devices School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyNSW2007Australia

In this study,we successfully synthesized Er_(2)TiO_(5)@Ag nanocomposites(NCPs) using the ultrasonicmediated sol-gel technique to create a multifunctional material with enhanced photocatalytic and antibacterial *** visible light photocatalytic activities of Er_(2)TiO_(5) nanoparticles(NPs) and Er_(2)TiO_(5)@Ag NCPs were systematically evaluated under various conditions,including different concentrations of Basic Blue 41(BB 41) dye and *** results reveal a remarkable improvement in the photocatalytic degradation efficiency of Er_(2)TiO_(5)@Ag NCPs(95%) compared to Er_(2)TiO_(5) NPs(80%).Furthermore,the antibacterial efficacy of Er_(2)TiO_(5) NPs and Er2TiO_5@Ag NCPs were extensively examined against Gram-positive and Gram-negative ***,Er_(2)TiO_(5)@Ag NCPs exhibit significantly higher minimum bactericidal concentration(MBC) values compared to Er_(2)TiO_(5) *** antibacterial effect of Er_(2)TiO_(5)@Ag NCPs is particularly pronounced against *** and Pseudomonas aeruginosa,while demonstrating moderate effects on Escherichia coli and Enterococcus *** assess the biocompatibility of the synthesized materials,we investigated their internalization by MCF-7 ***,both Er_(2)TiO_(5) NPs and Er_(2)TiO_(5)@Ag NCPs are found to be effectively internalized by the cells,suggesting their potential application in biomedical ***,our study unveils the exceptional potential of Er_(2)TiO_(5)@Ag NCPs as a dual-action solution,simultaneously possessing enhanced photocatalytic efficiency and potent antibacterial *** multifunctional nanocomposite not only outperforms Er_(2)TiO_(5) and Ag but also paves the way for innovative applications in sustainable environmental remediation and advanced biomedical technologies,promising a brighter and cleaner future.

关键词： Rare earth catalysis Nanocomposite Er_(2)TiO_(5)@Ag Antibacterial activity Photocatalysis Cytotoxicity

Time-Series Embeddings from Language Models:A Tool for Wind Direction Nowcasting

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Journal of Meteorological Research 2024年第3期38卷 558-569页

作者： Decio ALVES Fabio MENDONCA Sheikh Shanawaz mostafa Fernando MORGADO-DIAS University of Madeira Campus Universitário da Penteada9020-105FunchalPortugal Interactive Technologies Institute/Laboratory for Robotics and Engineering Systems and Agência Regional para o Desenvolvimento da Investigação Tecnologia e InovaçãoEdif.Madeira TecnopoloCaminho da Penteada piso-29020-105FunchalPortugal

Wind direction nowcasting is crucial in various sectors,particularly for ensuring aviation operations and *** this context,the TELMo(Time-series Embeddings from Language Models)model,a sophisticated deep learning architecture,has been introduced in this work for enhanced wind-direction *** by using three years of data from multiple stations in the complex terrain of an international airport,TELMo incorporates the horizontal u(east-west)and v(north-south)wind components to significantly reduce forecasting *** a day with high wind direction variability,TELMo achieved mean absolute error values of 5.66 for 2-min,10.59 for 10-min,and 14.79 for 20-min forecasts,processed within a swift 9-ms/step *** degree-based analysis,in comparison,yielded lower performance,emphasizing the effectiveness of the u and v *** contrast,a Vanilla neural network,representing a shallow-learning approach,underperformed in all analyses,highlighting the superiority of deep learning methodologies in wind direction *** is an efficient model,capable of accurately forecasting wind direction for air traffic operations,with an error less than 20°in 97.49%of the predictions,aligning with recommended international *** model design enables its applicability across various geographical locations,making it a versatile tool in global aviation meteorology.

关键词： wind nowcasting wind components wind direction time series prediction deep learning