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Improved Dijkstra Algorithm for Mobile Robot Path Planning and Obstacle Avoidance

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

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A Hybrid Particle Swarm Optimization to Forecast Implied Volatility Risk

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Computers, Materials & Continua 2022年第11期73卷 4291-4309页

作者： Kais Tissaoui sahbi boubaker Waleed Saud Alghassab Taha Zaghdoudi Jamel Azibi University of Ha’il Applied CollegeHail CitySaudi Arabia University of Tunis El Manar Faculty of Economic Sciences and Management of Tunisthe International Finance GroupTunisTunisia Department of Computer and Network Engineering College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Research Unit on Study of Systems and Renewable Energy National College of Engineering of MonastirUniversity of MonastirMonastirTunisia LAREQUAD&FSEGT University of Tunis El ManarTunisTunisia University of Jendouba Law FacultyManagement and Economic Sciences of JendoubaTunisia

The application of optimization methods to prediction issues is a continually exploring *** line with this,this paper investigates the connectedness between the infected cases of COVID-19 and US fear index from a forecasting *** complex characteristics of implied volatility risk index such as non-linearity structure,time-varying and nonstationarity motivate us to apply a nonlinear polynomial Hammerstein model with known structure and unknown *** use the Hybrid Particle Swarm Optimization(HPSO)tool to identify the model parameters of nonlinear polynomial Hammerstein *** indicate that,following a nonlinear polynomial behaviour cascaded to an autoregressive with exogenous input(ARX)behaviour,the fear index in US financial market is significantly affected by COVID-19-infected cases in the US,COVID-19-infected cases in the world and COVID-19-infected cases in China,*** performance indicators provided by the developed models show that COVID-19-infected cases in the US are particularly powerful in predicting the Cboe volatility index compared to COVID-19-infected cases in the world and China(MAPE(2.1013%);R2(91.78%)and RMSE(0.6363 percentage points)).The proposed approaches have also shown good convergence characteristics and accurate fits of the data.

关键词： Forecasting Cboe’s volatility index COVID-19 pandemic nonlinear polynomial hammerstein model hybrid particle swarm optimization

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Robust Particle Swarm Optimization Algorithm for Modeling the Effectof Oxides Thermal Properties on AMIG 304L Stainless Steel Welds

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Computer Modeling in Engineering & Sciences 2024年第11期141卷 1809-1825页

作者： Rachid Djoudjou Abdeljlil Chihaoui Hedhibi Kamel Touileb Abousoufiane Ouis sahbi boubaker Hani Said Abdo Department of Mechanical Engineering College of Engineering in Al-KharjPrince Sattam bin Abdulaziz UniversityP.O.Box 655Al-Kharj16273Saudi Arabia Department of Computer and Network Engineering College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Laboratory of Mechanics of Sousse(LMS) National Engineering School of SousseUniversity of SousseSousse4054Tunisia Center of Excellence for Research in Engineering Materials(CEREM) King Saud UniversityP.O.Box 800Al-Riyadh11421Saudi Arabia Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining EngineeringSuez UniversitySuez43512Egypt

There are several advantages to the MIG(Metal Inert Gas)process,which explains its increased use in variouswelding sectors,such as automotive,marine,and construction.A variant of the MIG process,where the sameequipment is employed except for the deposition of a thin layer of flux before the welding operation,is the AMIG(Activated Metal Inert Gas)*** study focuses on investigating the impact of physical properties ofindividual metallic oxide fluxes for 304L stainless steel welding joint morphology and to what extent it can helpdetermine a relationship among weld depth penetration,the aspect ratio,and the input physical properties ofthe *** types of oxides,TiO_(2),SiO_(2),Fe_(2)O_(3),Cr_(2)O_(3),and Mn_(2)O_(3),are tested on butt joint design withoutpreparation of the edges.A robust algorithm based on the particle swarm optimization(PSO)technique is appliedto optimally tune the models’parameters,such as the quadratic error between the actual outputs(depth and aspectratio),and the error estimated by the models’outputs is *** results showed that the proposed PSOmodel is first and foremost robust against uncertainties in measurement devices and modeling errors,and second,that it is capable of accurately representing and quantifying the weld depth penetration and the weld aspect ratioto the oxides’thermal properties.

关键词： Activated metal inert gas welding stainless steel activating flux oxides’thermal properties particle swarm optimization

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EXISTENCE OF SOLUTIONS FOR GRADIENT SYSTEMS WITH APPLICATION TO DIFFUSION PROBLEMS INVOLVING NONCONVEX ENERGIES

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Acta Mathematica Scientia 2018年第6期38卷 1767-1778页

作者： sahbi BOUSSANDEL Dpartement de Mathmatiques Facult des Sciences de Bizerte

In this paper, we establish the existence of solutions for gradient systems ofevolution under some type （M） and semi-coerciveness conditions. The main result is appliedin order to solve nonlinear diffusion equations... 详细信息

关键词： gradient systems existence of solutions Galerkin method type (M) condition semi-coerciveness diffusion equations

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EXISTENCE AND UNIQUENESS OF PERIODIC SOLUTIONS FOR GRADIENT SYSTEMS IN FINITE DIMENSIONAL SPACES

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Acta Mathematica Scientia 2016年第1期36卷 233-243页

作者： sahbi BOUSSANDEL Faculte des Sciences de Gabes 6072 Zrig Gabes Citd Riadh Tunisia-Laboratoire EDP et Applications LR03ES04 Tunisia

This paper deals with an abstract periodic gradient system in which the gradient is taken with respect to a variable metric. We obtain an existence and uniqueness result via the application of a global inverse theorem.

关键词： existence and uniqueness periodic solutions gradient systems global inversetheorem

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Contribution of Geophysical Prospecting(Geoelectrical Method) for the Hydrogeological Reconnaissance of the Region of Ouled Youssef(Tadla's Basin,Morocco)

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地学前缘 2009年第S1期16卷 130-131页

作者： Sanaa el Batali Hassane sahbi Ali Essahlaoui Mustapha Boualoul Geological Engineering Laboratory Faculty of Sciences

The Turonian aquifer of the Tadla’s basin shows at present a pronounced reduction of its hydraulic potential linked to overexploitation and deficiency of effective *** order to make an evaluation of the resources of ... 详细信息

关键词： Morocco Tadla’s basin climatology geoelectrical method Turonian aquifer isoresistivity geoelectric sections exploitation’s drillings

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Testicular torsion in undescended testis:A persistent challenge

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Asian Journal of Urology 2017年第2期4卷 111-115页

作者： sahbi Naouar Salem Braiek Rafik El Kamel Urology Department Les Aghlabites Surgical DivisionIbn El Jazzar Teaching HospitalKairouanTunisia

Objective:To evaluate the management and outcomes of patients who presented with torsion of an undescended testis and review the reported series in the ***:The case records of 13 patients operated for testicular torsion involving undescended testis were retrospectively *** medical records included age at presentation,medical history,physical examination,operative findings and the results of *** diagnosis of torsion of undescended testis was made clinically and confirmed by inguinal ***:In six cases the testis was preserved and orchiopexy was performed,while in seven cases orchidectomy was performed due to testicular gangrene in six patients and testicular tumor discovered peroperatively in one *** duration of symptoms at time of surgery in the orchiopexy group was 6.5 h and in the orchidectomy group was 21.2 *** six patients treated by orchiopexy,two patients suffered from testicular atrophy at a mean of 24 ***:Testicular torsion in undescended testis is still diagnosed with delay which may affect testicular *** importance of examination of external genital organs is highlighted which should be routinely included by emergency physicians in physical examination for abdominal or groin pain.

关键词： Testis torsion Undescended testis Misdiagnosis Salvageability

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First Principles Study of the Structural and Electronic Properties of the ZnO/Cu<sub>2</sub>O Heterojunction

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Materials Sciences and Applications 2015年第7期6卷 661-675页

作者： Mabrouk Zemzemi sahbi Alaya Laboratory of Physics of Materials and Nanomaterials applied to Environment Faculty of Sciences of Gabes University of Gabes Gabes Tunisia

Many materials have been used in nanostructured devices;the goal of attaining high-efficiency thin-film solar cells in such a way has yet to be achieved. Heterojunctions based on ZnO/Cu2O oxides have recently emerged as promising materials for high-efficiency nanostructured devices. In this work, we are interested in the characterization of the surface and interface through nano-scale modeling based on ab initio (Density Functional Theory (DFT), Local Density Approximation (LDA), Generalized Gradient Approximation (GGA-PBE), and Pseudopotential (PP)). This study aims also to build a supercell containing a ZnO/Cu2O heterojunction and study the structural properties and the discontinuity of the valence band (band offset) from a semiconductor to an-other. We investigate crystal terminations of ZnO (0001) and Cu2O (0001). We calculate the energies of the polar surfaces and the work function in the c-axis for both oxides. We built a zinc oxide layer in the wurtzite structure along the [0001] direction, on which we placed a copper oxide layer in the hexagonal structure (CdI2-type). We choose the method of Van de Walle and Martin to calcu-late the energy offset. This approach fits well with the DFT. Our calculations give us a value that corresponds to other experimental and theoretical values.

关键词： Heterojunction Structure and Electronic Properties Band Offsets Surface Energy Workfunction Density Functional Theory Average Potential Method

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A Review of the Advances Made in Improving the Durability of Welded Wood against Water in Light of the Results of African Tropical Woods Welding

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Journal of Renewable Materials 2023年第3期11卷 1077-1099页

作者： Jean Jalin Eyinga Biwôlé Achille Bernard Biwolé Antonio Pizzi Joseph Zobo Mfomo César Segovia Atangana Ateba Evariste Fedoung Fongnzossie sahbi Ouertani Xinyi Chen Bénoît Ndiwe DieudonnéAbessolo Pierre-Jean Meausoone Laboratory of Forest Resources and Wood Valorization University of DoualaP.O.Box.2701DoualaCameroon Laboratory of Mechanics University of DoualaP.O.Box.2701DoualaCameroon CETELOR University of LorraineP.O.Box.21042EpinalFrance ENSTIB-LERMAB University of LorraineP.O.Box.21042EpinalFrance Laboratory of Energetics and Thermal and Mass Transfers El Manar University of TunisTunisTunisia

Wood plays a major role in the production of furniture and wooden ***,in this process,the massive use of adhesives and plural connectors remains a definite problem for health and the ***,wood welding is a breakthrough in this *** paper reviews the applications of wood welding in furniture and construction and then examines advances in improving the durability of welded wood against *** contribution also highlights the need to join African tropical woods using the rotational friction welding *** to our results,these woods present interesting chemical singularities,which could provide solutions to the water vulnerability of the welded ***,the use of such a joining method would first free the Cameroonian furniture industry from the chemical industry,secondly position it at the forefront of new eco-design trends and thirdly make it competitive with other countries in the Central African *** works enrich the long and rich bibliography on the technique of wood welding,which has long been conspicuous by its absence of tropical woods.

关键词： Wood welding tropical woods water vulnerability chemical singularities natural durability

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京津地区流浪犬及家养犬消化道寄生虫感染调查

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中国病原生物学杂志 2017年第12期12卷 1203-1205页

作者：杨舒孟超楚旭刘阳 sahbi Khaled Taieb 路丹崔博豪陈莎彭鹏陈苓苓纪伟华胡立志天津医科大学基础医学院病原生物学与免疫学系天津300070 天津市第二人民医院检验科

目的了解京津地区流浪犬及家养犬消化道寄生虫感染情况。方法 2016年6月-2017年7月采集京津地区家养犬及流浪犬粪便标本。采用醛醚沉淀法查寄生虫虫卵。结果流浪犬及家养犬消化道寄生虫总感染率为52.99%,其中流浪犬感染率为79.68%,家养... 详细信息

目的了解京津地区流浪犬及家养犬消化道寄生虫感染情况。方法 2016年6月-2017年7月采集京津地区家养犬及流浪犬粪便标本。采用醛醚沉淀法查寄生虫虫卵。结果流浪犬及家养犬消化道寄生虫总感染率为52.99%,其中流浪犬感染率为79.68%,家养犬感染率为22.56%,差异有统计学意义(χ~2=114.43,P<0.05)。犬消化道蠕虫、原虫感染率分别为39.32%和28.49%。蠕虫感染中犬钩虫、犬蛔虫、绦虫、华支睾吸虫感染率分别为25.64%、15.67%、0.57%和5.70%,优势种为犬钩虫和犬蛔虫。流浪犬犬钩虫、犬蛔虫、绦虫、华支睾吸虫、原虫感染率分别为45.99%、22.46%、0.68%、9.09%和40.64%,家养犬对应寄生虫感染率依次为2.44%、7.93%、0.61%、1.83%和14.63%,流浪犬犬钩虫感染率与家养犬比较差异有统计学意义(χ~2=86.91,P<0.05)。感染犬中多重感染占32.26%,流浪犬多重感染占比37.58%与家养犬多重感染占比10.81%比较差异有统计学意义(χ~2=9.72,P<0.05)。结论京津地区犬消化道寄生虫感染率较高,以流浪狗犬感染情况更为严重。

关键词：消化道寄生虫流行情况流浪犬家养犬

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