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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.

The antiaging role of oxytocin

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Neural Regeneration Research 2021年第12期16卷 2413-2414页

作者： tarek Benameur Maria A.Panaro Chiara Porro College of Medicine Department of Biomedical SciencesKing Faisal University Al-AhsaKingdom of Saudi Arabia Department of Biosciences Biotechnologies and BiopharmaceuticsUniversity of BariBariItaly Department of Clinical and Experimental Medicine University of FoggiaFoggiaItaly

The human life expectancy is continuously *** the past two decades,a large number of studies have been extensively exploring the molecular mechanisms which play critical roles in determining *** is a physiological and... 详细信息

关键词： aging continuously physiological

Attenuation of Rayleigh Surface Waves in a Porous Material

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Chinese Physics Letters 2012年第4期29卷 123-125页

作者： DEBBOUB Salima BOUMAIZA Youcef BOUDOUR Amar TAhRAOUI tarek Laboratory of Materials Elaboration and Analysis Department of PhysicsFaculty of SciencesUniversity of AnnabaP.O.BOX 1223000 AnnabaAlgeria

Using acoustic microscopy at higher frequency,we show the velocity evolutions of surface acoustic waves,in particular Rayleigh waves that depend on porosity for a mesoporous silicon *** velocities are obtained from different V(z) curves,which are determined experimentally at a frequency of *** analysis of V(z) data yields attenuation that is directly dependent on *** the other hand,αN attenuation has been modeled and allows us to investigate its influence on the velocity VR of the propagation for Rayleigh waves.

关键词： layer porosity Porous

Performance characterization of different configurations of gas turbine engines

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Propulsion and Power Research 2014年第3期3卷 121-132页

作者： tarek Nada National Authority of Remote Sensing and Space Sciences CairoPO box 1564 Alf-MaskanEgypt

This paper investigates the performance of different configurations of gas turbine engines.A full numerical model for the engine is *** model takes into account the variations in specific heat and the effects of turbine cooling flow.A lso,the model considers the efficiencies of all component,effectiveness of heat exchangers and the pressure drop in relevant *** model is employed to compare the engine performances in cases of employing intercooler,recuperation and reheat on a single spool gas turbine engine.A comparison is made between single-spool engine and two-spool engine with free power ***,the performance of the eng ine with inter-stage turbine burner is investigated and compared with engine employing the nominal reheat *** engine employing inter-stage turbine bumers produces superior improvements in both net work and efficiency over all other *** effects of ignoring the variations on specific heat of gases and turbine cooling flow on engine performance are *** the variation in specific heat can cause up to 30%difference in net specific *** optimum locations of the intercooler and the reheat combustor are detemined using the numerical model of the *** maximum net specific work is obtained if the reheat combustor is placed at 40%of the expansion *** the other hand,to get maximum efficiency the reheat combustor has to be placed at nearly 10%-20%of the expansion *** optimum location of the intercooler is almost at 50%of the compression section for both maximum net specific work and efficiency.

关键词： Gas turbine Power plant Optimum design Engine parameters

Comparative study on hash functions for lightweight blockchain in Internet of Things(IoT)

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Blockchain(Research and Applications) 2021年第4期2卷 49-55页

作者： Aishah Alfrhan tarek Moulahi Abdulatif Alabdulatif Department of Information Technology College of ComputerQassim UniversityBuraydah51013Saudi Arabia Department of Computer Science College of ComputerQassim UniversityBuraydah51013Saudi Arabia

Over the last few years,there has been a great interest in the Internet of Things(IoT).This is mainly because the IoT interacts directly with people's everyday lives in critical applications,such as in smart homes and healthcare *** devices typically have a resource-constrained architecture,rendering them vulnerable to ***,smart devices and stored data need to be secured through lightweight and energyefficient security solutions,which have been identified as the main challenge facing adoption of IoT *** address this problem,a disruptive technology(blockchain)has been foreseen by the industry and research community as being able to deliver secure,fast,reliable,and transparent solutions for IoT ***,this work investigates the adoption of lightweight blockchain technology,mainly as a method of securing IoT *** hashing plays a major role in creating a robust blockchain structure,we select a number of different hash techniques to be executed on a Raspberry Pi *** summation,this work provides a numerical study to evaluate the performance of well-known hash functions that can be used for lightweight blockchain-based IoT.

关键词： Lightweight blockchain Internet of Things(IoT) hash Cybersecurity

Silicon-mediated highly efficient synthesis of 1,8-dioxo-octahydroxanthenes and their transformation to novel functionalized pyrano-tetrazolo[1,5-a]azepine derivatives

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Chinese Chemical Letters 2013年第5期24卷 404-406页

作者： hanan A.Soliman tarek A.Salama Photochemistry Department National Research Center Chemistry Department Faculty of ScienceMansoura University

A facile and highly efficient protocol for the synthesis of 1,8-dioxo-octahydroxanthene derivatives was achieved through cascade Knoevenagel-Michael condensations and cyclo-dehydration reaction utilizing tetrachlorosilane（TCS） as catalyst under mild *** of the titled compounds with TCSNaN_3 to give novel functionalized pyrano[3,2-c]tetrazolo[1,5-a]azepine derivatives is also described.

关键词： Tetrachlorosilane 1,8-Dioxo-octahydroxanthenes Synthesis Tetrazoln[1,5-a]azepines

Double compound combination synchronization among eight n-dimensional chaotic systems

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Chinese Physics B 2018年第8期27卷 150-158页

作者： Gamal M Mahmoud tarek M Abed-Elhameed Ahmed A Farghaly Department of Mathematics Faculty of Science Assiut University

Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization （DCCS） of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the MATLAB simula- tion outcomes. We obtain the same results of numerical treatment of our synchronization using simulation observations of our example.

关键词： double compound synchronization compound combination synchronization chaotic system Lya-punov stability

Geospatial susceptibility mapping of earthquake-induced landslides in Nuweiba area, Gulf of Aqaba, Egypt

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Journal of Mountain Science 2016年第7期13卷 1286-1303页

作者： Sara ABUZIED Samia IBRAhIM Mona KAISER tarek Saleem Center for Spatial Analysis University of Oklahoma Geology Departments Faculty of Science Suez Canal University

Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area.

关键词： Geographic Information Systems(GIS) Remote Sensing(RS) Landslides Susceptibility mapping Weights Nuweiba area

Silicon mediated synthesis and selected transformations of β-chloroketones

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Chinese Chemical Letters 2011年第10期22卷 1171-1174页

作者： tarek A.Salama Saad S.Elmorsy Chemistry Department Faculty of ScienceMansoura University35516 MansouraEgypt Chemistry Department Faculty of EducationAmran UniversityAmranYemen

A combination of tetrachlorosilane（TCS） and phenol in dichloromethane was found to be an efficient reagent for hydro-chlorination ofα,β-unsaturated ketones to afford the correspondingβ-chloroketones in good yield at ambient temperature. Reactions of the titled compounds with TCS-NaN_3 as well as with nitriles utilizing TCS-ZnCl_2 to give 1,5-disubstituted tetrazole derivatives orβ-amido ketones respectively are also described.

关键词： Tetrachlorosilane Phenol β-Chloroketones Synthesis Tetrazoles β-Amido ketones