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Improved Dijkstra Algorithm for Mobile Robot Path Planning and Obstacle Avoidance

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Computers, Materials & Continua 2022年第9期72卷 5939-5954页

作者： Shaher Alshammrei Sahbi Boubaker lioua kolsi Department of Mechanical Engineering College of EngineeringUniversity of Ha’ilHa’il2440Saudi Arabia Department of Computer and Network Engineering College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Research Laboratory of Metrology and Energy Systems National Engineering SchoolEnergy Engineering DepartmentUniversity of MonastirMonastir5000Tunisia

Optimal path planning avoiding obstacles is among the most attractive applications of mobile robots(MRs)in both research and *** this paper,an optimal collision-free algorithm is designed and implemented practically based on an improved Dijkstra *** achieve this research objectives,first,the MR obstacle-free environment is modeled as a diagraph including nodes,edges and ***,Dijkstra algorithm is used offline to generate the shortest path driving the MR from a starting point to a target *** its movement,the robot should follow the previously obtained path and stop at each node to test if there is an obstacle between the current node and the immediately following *** this aim,the MR was equipped with an ultrasonic sensor used as obstacle *** an obstacle is found,the MR updates its diagraph by excluding the corresponding ***,Dijkstra algorithm runs on the modified *** procedure is repeated until reaching the target *** verify the efficiency of the proposed approach,a simulation was carried out on a hand-made MR and an environment including 9 nodes,19 edges and 2 *** obtained optimal path avoiding obstacles has been transferred into motion control and implemented practically using line tracking *** study has shown that the improved Dijkstra algorithm can efficiently solve optimal path planning in environments including obstacles and that STEAM-based MRs are efficient cost-effective tools to practically implement the designed algorithm.

关键词： Mobile robot(MR) STEAM path planning obstacle avoidance improved dijkstra algorithm

Heat and mass transfer enhancement in triangular pyramid solar still using CNT-water nanofluid

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Journal of Central South University 2021年第11期28卷 3434-3448页

作者： GHACHEM Kaouther kolsi lioua LARGUECH Samia ALNEMER Ghada Department of Industrial Engineering and Systems College of EngineeringPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Mechanical Engineering College of EngineeringHa’il UniversityHa’il CitySaudi Arabia Research Laboratory of Metrology and Energy Systems National Engineering SchoolEnergy Engineering DepartmentUniversity of MonastirMonastir 5000Tunisia Department of Electrical Engineering College of EngineeringPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Mathematical Science College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia

This work represents a 3 D numerical study of the effects of carbon nanotube(CNT)-water nanofluids on the double diffusive convection inside the triangular pyramid solar *** numerical investigation is performed for wide ranges of governing parameters such as buoyancy ratio(-10≤N≤0),volumetric fraction of nanoparticles(0≤Φ≤0.05) and Rayleigh number(10^(3)≤Ra≤10^(5)).The results are presented in terms of flow structure,temperature field,heat and mass transfer rates *** was found that the buoyancy ratio can be considered as an optimizing parameter for the heat and mass transfer,and the use of CNT has a positive effect on the solar still performances.

关键词： 3D solar still triangular pyramid solar still double diffusive convection CNT-water nanofluid

Three-dimensional analysis of natural convection in nanofluid-filled parallelogrammic enclosure opened from top and heated with square heater

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Journal of Central South University 2019年第5期26卷 1077-1088页

作者： Abdullah A.A.A AL-RASHED Walid HASSEN lioua kolsi Hakan F. OZTOP Ali J. CHAMKHA Nidal ABU-HAMDEH Department of Automotive and Marine Engineering Technology College of Technological Studiesthe Public Authority for Applied Education and TrainingKuwait Unité de Métrologie et des Systèmes énergétiques école Nationale d’IngénieursMonastirUniversity of MonastirTunisia College of Engineering Mechanical Engineering DepartmentHail UniversityHail CitySaudi Arabia Dept.Mech.Engineering Technology FacultyFirat UniversityTR-23119ElazigTurkey Department of Mechanical Engineering King Abdulaziz UniversityJeddahSaudi Arabia Mechanical Engineering Department Prince Sultan Endowment for Energy and EnvironmentPrince Mohammad Bin Fahd UniversityAl-Khobar 31952Saudi Arabia RAK Research and Innovation Center American University of Ras Al KhaimahP.O.Box 10021Ras Al KhaimahUnited Arab Emirates

A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the bottom *** are obtained for different governing parameters such as nanoparticle concentration (φ) from 0 to 0.05,inclination angle of the back and front walls (α) from 5° to 75°,Rayleigh number from 10^3 to 10^5,and length of heater changer from 0.1 to *** main finding from the obtained result showed that the inclination angle and nanoparticle volume fraction affect the flow structure and enhance the heat transfer.

关键词： 3D analysis open enclosure partial heating parallelogram nanofluids

Predictors of perioperative respiratory adverse events among children with upper respiratory tract infection undergoing pediatric ambulatory ilioinguinal surgery:a prospective observational research

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World Journal of Pediatric Surgery 2023年第2期6卷 97-102页

作者： Anouar Jarraya Manel Kammoun Saloua Ammar Wiem Feki Kamel kolsi The anesthesiology Department Hedi Chaker University HospitalUniversity of SfaxSfaxTunisia Faculty of Medicine of Sfax University of SfaxSfaxTunisiaFaculty of Medicine of SfaxUniversity of SfaxSfaxTunisia Department of Pediatric Surgery Hedi Chaker HospitalSfaxTunisiaFaculty of Medicine of SfaxUniversity of SfaxSfaxTunisia

Objectives Anesthesia for children with an upper respiratory tract infection(URI)has an increased risk of perioperative respiratory adverse events(PRAEs)that may be predicted according to the COLDS *** aims of this study were to evaluate the validity of the COLDS score in children undergoing ilioinguinal ambulatory surgery with mild to moderate URI and to investigate new predictors of *** This was a prospective observational study including children aged 1-5 years with mild to moderate symptoms of URI who were proposed for ambulatory ilioinguinal *** anesthesia protocol was *** were divided into two groups according to the incidence of *** logistic regression was performed to assess predictors for *** In this observational study,216 children were *** incidence of PRAEs was 21%.Predictors of PRAEs were respiratory comorbidities(adjusted OR(aOR)=6.3,95%CI 1.19 to 33.2;p=0.003),patients postponed before 15 days(aOR=4.3,95%CI 0.83 to 22.4;p=0.029),passive smoking(aOR=5.31,95%CI 2.07 to 13.6;p=0.001),and COLDS score of>10(aOR=3.7,95%CI 0.2 to 53.4;p=0.036).Conclusions Even in ambulatory surgery,the COLDS score was effective in predicting the risks of *** smoking and previous comorbidities were the main predictors of PRAEs in our *** seems that children with severe URI should be postponed to receive surgery for more than 15 days.

关键词： surgery ambulatory respiratory

Complications and its risk factors of percutaneous subclavian vein catheters in pediatric patients:enhancing the outcomes of a university hospital in a low-income and middle-income country

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World Journal of Pediatric Surgery 2023年第1期6卷 36-41页

作者： Anouar Jarraya Manel Kammoun Ameni Chtourou Saloua Ammar Kamel kolsi The Anesthesiology department University of Sfax Faculty of Medicine of SfaxSfaxTunisia Department of Pediatric Surgery Hedi Chaker HospitalSfaxTunisia University of Sfax Faculty of Medicine of Sfax SfaxTunisia

Objective Assessing central venous catheter-related complications with regular feedback and investigating risk factors are mandatory to enhance *** aim of this study is to assess our experience in the management of pediatric subclavian vein catheters(SVCs)and to investigate the main risk factors for *** In this prospective observational study,we included children aged 3 months to 14 years who underwent infraclavicular subclavian vein catheterization consecutively using the anatomic landmark *** were divided into two groups:group 1 included complicated catheters and group 2 included noncomplicated *** management protocol was standardized for all *** comparing the two groups,univariate and multivariate logistic regression were used to investigate the risk factors for *** In this study,we included 134 pediatric *** rate of complications was 32.8%.The main complications were central line-associated bloodstream infection(63.6%),bleeding and/or hematoma(22.7%),mechanical complications(13.6%),and vein thrombosis(13.6%).After adjustment for confounding factors,predictors of catheter-related complications were difficult insertion procedure(adjusted odds ratio(aOR)=9.4;95%confidential interval(CI):2.32 to 38.4),thrombocytopenia(aOR=4.43;95%CI:1.16 to 16.86),comorbidities(aOR=2.93;95%CI:0.58 to 14.7),and neutropenia(aOR=5.45;95%CI:2.29 to 13.0).Conclusions High rates of complications were associated with difficult catheter placement and patients with comorbidities and severe *** reduce catheter-related morbidity,we suggest an ultrasoundguided approach,a multidisciplinary teaching program to improve nursing skills,and the use of less invasive devices for patients with cancer.

关键词： patients catheter pediatric

Effectiveness of plant growth-promoting rhizobacterium Pantoea sp. BRM17 in enhancing canola growth on phosphogypsum-amended soil

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Pedosphere 2020年第4期30卷 570-576页

作者： Houda TRIFI Issam BENSALEM Naima kolsi BENZINA Amine FOURATI Maria Clara COSTA Wafa ACHOUAK Haitham SGHAIER Mouldi SAIDI Laboratory of Biotechnology and Nuclear Technology(LR16CNSTN01) National Center for Nuclear Sciences and Technology(CNSTN)Sidi Thabet Technopark 2020(Tunisia) Faculty of Sciences of Bizerte Carthage UniversityJarzouna 7021(Tunisia) Soil Sciences and Environment Laboratory National Institute of Agronomy of TunisiaTunis Mahrajene 1082(Tunisia) Tunisian Chemical Group Route de Gabes Km 3.5Sfax 3018(Tunisia) Centro de Ciencias do Mar Universidade do AlgarveCampus de GambelasFaro 8005-139(Portugal) Laboratory of Microbial Ecology of the Rhizosphere and Extreme Environment CEA CadaracheSaint Paul Lez Durance 13108(France) Laboratory of Energy and Matter for Development of Nuclear Sciences(LRJ6CNSTN02) National Center for Nuclear Sciences and Technology(CNSTN)Sidi Thabet Technopark 2020(Tunisia) Laboratory of Biotechnology and Bio-Georesources Valorization(LR1IES31) National Center for Nuclear Sciences and Technology(CNSTN)Sidi Thabet Technopark 2020(Tunisia)

Dear Editor,Phosphogypsum(PG)is the main by-product generated during phosphoric acid production from mineral *** contains mainly calcium sulfate dehydrate(CaSO4:2H2O),phosphate,fuoride,heavy metals,and radionuclides(Elloumi et al.,2015).Around 170×10^6 t PG is produced annually worldwide,although PG management is an environ-mental concern in several countries.

关键词： annually soil metals

Pressure-Driven Gas Flows in Micro Channels with a Slip Boundary:A Numerical Investigation

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Fluid Dynamics & Materials Processing 2020年第2期16卷 147-159页

作者： A.Aissa M.E.A.Slimani F.Mebarek-Oudina R.Fares A.Zaim L.kolsi M.Sahnoun M.E.Ganaoui Laboratoire de Physique Quantique de la Matière et Modélisation Mathématique(LPQ3M) University of MascaraMascaraAlgeria Department of Energetic and Fluid Mechanics University of Science and Technology Houari BoumedieneAlgiers16111Algeria Depatment of Physics Faculty of SciencesUniversity of 20 août 1955-SkikdaSkikdaAlgeria Mechanical Engineering Department College of EngineeringHaïl UniversityHaïl2240Saudi Arabia Laboratory of Metrology and Energy Systems University of MonastirMonastir5000Tunisia LERMAB IUT LongwyUniversitéde LorraineCosnes et Romain54400France

In this paper,flow of slightly rarefied compressible nitrogen in microchannels has been investigated numerically for low values of Reynolds and Mach *** 2D governing equations were solved using Finite Element Method with first-order slip boundary conditions(Comsol Multiphysics software).A validation was performed by comparing with similar configuration from the *** was found that our model can accurately predict the pressure driven flow in *** interesting findings are reported about the Relative pressure,longitudinal velocity,Mach number,effect of gas rarefaction and flow rate.

关键词： Pressure driven slip flow microchannels gas flow rarefactioneffect

Design Analysis of DC-DC Converters Connected to a Photovoltaic Generator and Controlled by MPPT for Optimal Energy Transfer throughout a Clear Day

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Journal of Power and Energy Engineering 2014年第1期2卷 27-34页

作者： S. kolsi H. Samet M. Ben Amar Department of Electronics Sfax High Institute of Electronics and Communications University of Sfax Sfax Tunisia Department of Physics Science Faculty of Sfax University of Sfax Sfax Tunisia Electronic Laboratory and Information Technology Department of Electrical Engineering Sfax National School of Engineers University of Sfax Sfax Tunisia

The DC-DC converters are widely used in photovoltaic generating systems as an interface between PV module and the load. These converters must be chosen to be able to match the maximum power point (MPP) of PV module when climatic conditions change with different resistive load values. So DC-DC converters must be used with MPPT controller in order to reduce losses in the global PV system. This article focuses on the effect of climatic conditions on design of two components (inductance, capacitance) for three topologies of DC-DC converters commonly used in PV systems. When climatic conditions change, the boundary of inductance and capacitance parameters of DC-DC converter will change. These two parameters must be properly sized to achieve optimal efficiency for each converter. The design optimization is based on two principles: 1) for a steady-state operation in a continuous conduction mode, the inductance value for all choppers must be greater than the maximum value of boundary inductance, and 2) in order to limit the output voltage ripple of DC-DC converter below a desired value, the filter capacitance must be larger than the maximum value of boundary capacitance.

关键词： DC-DC Converter Energy Efficiency Design Load Matching MPPT

A Hybrid GA-SQP Algorithm for Analog Circuits Sizing

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Circuits and Systems 2012年第2期3卷 146-152页

作者： Firas Yengui lioua Labrak Felipe Frantz Renaud Daviot Nacer Abouchi Ian O’Connor The Lyon Institute of Nanotechnology (INL) University of Lyon Lyon France

This study presents a hybrid algorithm obtained by combining a genetic algorithm (GA) with successive quadratic sequential programming (SQP), namely GA-SQP. GA is the main optimizer, whereas SQP is used to refine the results of GA, further improving the solution quality. The problem formulation is done in the framework named RUNE (fRamework for aUtomated aNalog dEsign), which targets solving nonlinear mono-objective and multi-objective optimization problems for analog circuits design. Two circuits are presented: a transimpedance amplifier (TIA) and an optical driver (Driver), which are both part of an Optical Network-on-Chip (ONoC). Furthermore, convergence characteristics and robustness of the proposed method have been explored through comparison with results obtained with SQP algorithm. The outcome is very encouraging and suggests that the hybrid proposed method is very efficient in solving analog design problems.

关键词： Genetic Algorithm Sequential Quadratic Programming Hybrid Optimization Analog Circuits Transimpedance Amplifier Optical Driver