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Flocking control of a fleet of unmanned aerial vehicles

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Control Theory and Technology 2018年第2期16卷 82-92页

作者： adel BELKADI Zhixiang LIU Laurent CIARLETTA Youmin ZHANG Didier THEILLIOL CRAN University of Lorraine Nancy France Department of Mechanical Industrial and Aerospace Engineering Concordia University Montreal Canada Lorraine Research Laboratory in Computer Science and its Applications (LORIA) University of Lorraine Nancy France

Current applications using single unmanned vehicle have been gradually extended to multiple ones due to their increased efficiency in mission accomplishment, expanded coverage areas and ranges, as well as enhanced system reliability. This paper presents a flocking control method with application to a fleet of unmanned quadrotor helicopters （UQHs）. Three critical characteristics of formation keeping, collision avoidance, and velocity matching have been taken into account in the algorithm development to make it capable of accomplishing the desired objectives （like forest/pipeline surveillance） by safely and efficiently operating a group of UQHs. To achieve these, three layered system design philosophy is considered in this study. The first layer is the flocking controller which is designed based on the kinematics of UQH. The modified Cucker and Smale model is used for guaranteeing the convergence of UQHs to flocking, while a repelling force between each two UQHs is also added for ensuring a specified safety distance. The second layer is the motion controller which is devised based on the kinetics of UQH by employing the augmented state-feedback control approach to greatly minimize the steady-state error. The last layer is the UQH system along with its actuators. Two primary contributions have been made in this work： first, different from most of the existing works conducted on agents with double integrator dynamics, a new flocking control algorithm has been designed and implemented on a group of UQHs with nonlinear dynamics. Furthermore, the constraint of fixed neighbouring distance in formation has been relaxed expecting to significantly reduce the complexity caused by the increase of agents number and provide more flexibility to the formation control. Extensive numerical simulations on a group of UQH nonlinear models have been carried out to verify the effectiveness of the proposed method.

关键词： Flocking unmanned aerial vehicles unmanned quadrotor helicopters Cucker and Smale formation control

Management of critical care emergencies in children with autism spectrum disorder

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World Journal of Critical Care Medicine 2025年第2期14卷 131-157页

作者： Mohammed Al-Beltagi Nermin Kamal Saeed adel Salah Bediwy Rawan Alhawamdeh Reem Elbeltagi Department of Pediatric Faculty of MedicineTanta UniversityTanta 31511AlghrabiaEgypt Department of Pediatric University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671ManamaBahrain Medical Microbiology Section Department of PathologySalmaniya Medical ComplexMinistry of HealthKingdom of BahrainManama 26671ManamaBahrain Medical Microbiology Section Department of PathologyIrish Royal College of SurgeonBahrainBusaiteen 15503MuharraqBahrain Department of Pulmonology Faculty of MedicineTanta UniversityTanta 31527AlghrabiaEgypt Department of Pulmonology University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671ManamaBahrain Department of Pediatrics Research and Development Sensoryme Dwc-llcDubai 712495DubaiUnited Arab Emirates Department of Pediatrics Research and Development Genomics Sensory Play and Creativity CenterManama 22673ManamaBahrain Department of Medicine The Royal College of Surgeons in Ireland-BahrainBusiateen 15503MuharraqBahrain

BACKGROUND Managing critical care emergencies in children with autism spectrum disorder(ASD)presents unique challenges due to their distinct sensory sensitivities,communication difficulties,and behavioral *** strategies and protocols are essential for optimal care in these high-stress *** To systematically evaluate and synthesize current evidence on best practices for managing critical care emergencies in children with *** review focuses on key areas,including sensory-friendly environments,communication strategies,behavioral management,and the role of multidisciplinary *** A comprehensive search was conducted across major medical databases,including PubMed,Embase,and Cochrane Library,for studies published between 2000 and *** were selected based on their relevance to critical care management in children with ASD,encompassing randomized controlled trials,observational studies,qualitative research,and case *** were extracted and analyzed to identify common themes,successful strategies,and areas for *** The review identified 50 studies that met the inclusion *** highlighted the importance of creating sensory-friendly environments,utilizing effective communication strategies,and implementing individualized behavioral management *** findings,derived from a comprehensive review of current evidence,provide valuable insights into the best practices for managing critical care emergencies in children with *** modifications,such as reduced lighting and noise,visual aids,and augmentative and alternative communication tools,enhanced patient comfort and *** involvement of multidisciplinary teams was crucial in delivering holistic *** studies provided practical insights and underscored the need for continuous refi-nement of *** The review emphasizes the need for a tailored approach to managing critical care emergencies for children with ASD.

关键词： Autism spectrum disorder Critical care emergencies Sensory sensitivities Behavioral management Communication strategies Multidisciplinary approach Pediatric intensive care Emergency protocols

Robust design and analysis for opto-mechanical two array laser warning system

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Defence Technology（防务技术） 2023年第9期27卷 46-52页

作者： Mazhar Tayel Mohamed Shehata Mohamed Mabrouk Abdlarhman adel Mohamed Shady Shokry Mostafa Alshershby Faculty of Engineering Alexandria UniversityAlexandriaEgypt Egyptian Air Defense Collage AlexandriaEgypt Laser and Optoelectronics Department Technical Research CenterEgypt

In the past three decades,laser warning systems(LWS)have emerged in great importance,as the development of laser-guided weapons,such as airborne Hellfire missiles,has increased,posing an imminent threat to vital areas and *** laser warning station(LWS)can detect,classify,identify,and give alarm from laser threat at a very short time with high ***,the designers of this system must take into account the detectability and field of view to cover the area to be *** main contribution in this research is an analytical design of LWS that consists of 24 detector elements,distributed in two arrays(2×12)***,calculating the best distance between the detectors according to the laser beam spot *** addition,enhancement laser warring sensor detection capability and detection performance FOV between the detectors to increase coverage area up to 360°.Moreover,decreasing dead zone area between the laser detectors *** calculations and illustrations made to reach the best systematic design.

关键词： LWS Field of view Detector elements

Recent advances in crystal phase induced surface-enhanced Raman scattering

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Chinese Chemical Letters 2024年第9期35卷 111-118页

作者： Ce Liang Qiuhui Sun adel Al-Salihy Mengxin Chen Ping Xu MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

Surface-enhanced Raman scattering(SERS)spectroscopy has emerged as a powerful analytical technique for detecting and identifying trace chemical and biological *** this review,we present an indepth discussion of recent advances in the field of crystal phase manipulation to achieve exceptional SERS *** on transition metal dichalcogenides,(hydr)oxides,and carbides as exemplary materials,we illustrate the pivotal role of crystal phase regulation in enhancing SERS *** exploring the correlation between crystal phases and SERS responses,we uncover the underlying principles behind these strategies,thereby shedding light on their potential for future SERS *** addressing the current challenges and limitations,we also propose the prospects of the crystal phase strategy to facilitate the development of cutting-edge SERS-based sensing technologies.

关键词： Surface-enhanced Raman scattering Crystal phase manipulation Transition metal dichalcogenides Transition metal oxides Transition metal carbides

Islands of stability and quasi-magic numbers for super- and ultra-heavy nuclei

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Chinese Physics C 2016年第12期40卷 69-90页

作者： M.Ismail A.Y.Ellithi A.adel Hisham Anwer Physics Department Faculty of Science Cairo University Physics Department College of Science Majmaah University Physics Department German University in Cairo

In the framework of Strutinsky＇s approach, we calculated the shell and the residual pairing correction energies for 5569 even-even nuclei in the range 72 ≤ Z ≤ 282 and 96≤N ≤ 540. Quasi-magic numbers and deformed islands of stability that reside in a range defined by Green＇s formula and the two-neutrons drip line are introduced. We present 36 quasi-magic proton and 53 quasi-magic neutron magic numbers that contribute to the formation of 133 deformed islands of stability along the N-Z space. The quasi-magic proton and neutron magic numbers volatile as the mass number increases and other magic numbers take over. Consequently, the deformed islands of stability fail to exhibit a pattern along the search space covered.

关键词： deformed nuclei islands of stability magic numbers

Pattern and determinants of tail-risk transmission between cryptocurrency markets:new evidence from recent crisis episodes

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Financial Innovation 2024年第1期10卷 2227-2260页

作者： Aktham Maghyereh Salem adel Ziadat Department of Accounting and Finance United Arab Emirates UniversityAl AinUnited Arab Emirates Faculty of Business Al-Ahliyya Amman University JordanAmmanJordan Division of Accounting and Finance University of StirlingStirlingUK

The main objective of this study is to investigate tail risk connectedness among six major cryptocurrency markets and determine the extent to which investor sentiment,economic conditions,and economic uncertainty can predict tail risk *** the Conditional Autoregressive Value-at-Risk(CAViaR)model with the time-varying parameter vector autoregressive(TVP-VAR)approach shows that the transmission of tail risks among cryptocurrencies changes dynamically over *** crises and significant events,transmission bursts and tail risks *** on both in-and out-of-sample forecasts,we find that the information contained in investor sentiment,economic conditions,and uncertainty includes significant predictive content about the tail risk connectedness of cryptocurrencies.

关键词： Tail-risk connectedness Cryptocurrency CAViaR TVP-VAR Predictability

Sensitivity analysis of energy inputs and economic evaluation of pomegranate production in Iran

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Information Processing in Agriculture 2018年第1期5卷 114-123页

作者： Mehdi Esmailpour Troujeni Mehdi Khojastehpour adel Vahedi Bagher Emadi Department of Biosystems Engineering Ferdowsi University of MashhadMashhadIran Agricultural Engineering Research Institute(AERI) Agricultural Research Education and Extension Organization(AREEO)KarajIran

The aim of this research was to investigate the energy use and costs of pomegranate production in Behshahr city(Mazandaran province)of *** required data were gathered by questionnaire and face to face interviews with 83 pomegranate ***-Douglas model and sensitivity analysis were employed for energy flows modeling of the production *** total energy inputs and energy output of production were determined to be 11195.06 and 13276.56 MJ ha1,and two inputs of diesel fuel and chemical fertilizers with the shares of 45.81 and 23.47%,were the highest energy consumers for pomegranate *** use efficiency,energy productivity and net energy were 1.18,2081.50 MJ ha1 and 0.62 kg MJ1,*** results of Cobb-Douglas model showed that the effect of the energy inputs including human labor,biocides,chemical fertilizers,farmyard manure,electricity and water for irrigation on pomegranates yield were positive,while the effects of diesel fuel and agricultural machinery were negative on the pomegranate *** sensitivity analysis results of energy inputs showed that with the increase of one MJ in the energy input of water for irrigation and chemical fertilizers,the yield was increased to 3.12 and 1.42 kg,*** with the increase of one MJ in diesel fuel and agricultural machinery inputs,the yield was decreased to 0.67 and 0.47 kg,*** fuel as the most used energy input in the production accounted for 0.85%of variable costs and the benefit to cost ratio was determined to be 5.57.

关键词： Benefit to cost Cobb-Douglas Energy modeling Energy pattern Pomegranate

Performance Assessment of a Real PV System Connected to a Low-Voltage Grid

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Energy Engineering 2024年第1期121卷 13-26页

作者： Gaber Magdy Mostafa Metwally adel A.Elbaset Esam Zaki Electrical Engineering Department Faculty of Energy EngineeringAswan UniversityAswanEgypt `2Faculty of Engineering King Salman International UniversityEl-Tor46511Egypt Electrical Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Department of Electromechanics Engineering Faculty of EngineeringHeliopolis UniversityCairoEgypt Computer Department Faculty of EngineeringModern Academy of Engineering&TechnologyCairoEgypt

The generation of photovoltaic(PV)solar energy is increasing continuously because it is renewable,unlimited,and clean *** the past,generation systems depended on non-renewable sources such as oil,coal,and ***,this paper assesses the performance of a 51 kW PV solar power plant connected to a low-voltage grid to feed an administrative building in the 6th of October City,*** performance analysis of the considered grid-connected PV system is carried out using power system simulator for Engineering(PSS/E)*** the PSS/E program,monitors and uses the power analyzer that displays the parameters and measures some parameters such as current,voltage,total power,power factor,frequency,and current and voltage harmonics,the used inverter from the type of grid inverter for the considered *** results conclude that when the maximum solar radiation is reached,the maximum current can be obtained from the solar panels,thus obtaining the maximum power and power *** total voltage harmonic distortion,a current harmonic distortion within permissible limits using active harmonic distortion because this type is fast in processing up to 300 *** connection between solar stations and the national grid makes the system more efficient.

关键词： Low-voltage grid photovoltaic(PV)system total harmonic distortion grid-connected PV system

Stabilization of chromium(Ⅵ) by hydroxysulfate green rust in chromium(Ⅵ)-contaminated soils

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Pedosphere 2021年第4期31卷 645-657页

作者： Leila ALIDOKHT Shahin OUSTAN Alireza KHATAEE Mohammad R.NEYSHABURI adel REYHANITABAR Faculty of Agriculture Department of Soil ScienceUniversity of TabrizTabriz 51666-16471(Iran) Research Laboratory of Advanced Water and Wastewater Treatment Processes Department of Applied ChemistryFaculty of ChemistryUniversity of TabrizTabriz 51666-16471(Iran) Department of Environmental Engineering Gebze Technical UniversityGebze 41400(Turkey)

Chromium(Cr)-contaminated soils pose a great environmental risk, with high solubility and persistent leaching of Cr(Ⅵ). In this study, hydroxysulfate green rust(GR_(SO4)), with the general formula Fe(Ⅱ)_(4) Fe(Ⅲ)_(2)(OH)_(12) SO_(4)·8 H_(2) O, was evaluated for its efficiency in Cr(Ⅵ) stabilization via Cr(Ⅵ) reduction to Cr(Ⅲ) in four representative Cr(Ⅵ)-spiked soils. The initial concentrations of phosphate buffer-extractable Cr(Ⅵ)(Cr(Ⅵ)b) in soils 1, 2, 3, and 4 were 382.4, 575.9, 551.3, and 483.7 mg kg^(-1), respectively. Reduction of Cr(Ⅵ) to Cr(Ⅲ) by structural Fe(Ⅱ)(Fe(Ⅱ)s) in GR_(SO4) in all studied soils was fast,wherein the application of GR_(SO4) markedly decreased the amount of Cr(Ⅵ)bat the Cr(Ⅵ)b/Fe(Ⅱ)s stoichiometric mole ratio of 0.33. The kinetics of Cr(Ⅵ)reduction by GR_(SO4) could not be determined as this reaction coincided with the release of Cr(Ⅵ) from soil during the experiment. The concentration of Cr(Ⅵ)bdecreased, as the Cr(Ⅵ)b/Fe(Ⅱ)s ratio decreased from 0.46 to 0.20, generally to below 10 mg kg^(-1). Back-transformation of the generated Cr(Ⅲ)was examined in the presence of manganese oxide birnessite at the birnessite/initial Cr(Ⅲ) mole ratio of 4.5. The results of batch tests showed that only 5.2% of the initial Cr(Ⅲ) was converted to Cr(Ⅵ) after two months, while under field capacity moisture conditions, less than 0.05% of the initial Cr(Ⅲ) was oxidized to Cr(Ⅵ) after six months. The results illustrated that remediation of Cr(Ⅵ)-contaminated soils would be fast, successful, and irreversible with an appropriate quantity of fresh GR_(SO_(4)).

关键词： batch system birnessite Cr(Ⅲ)oxidation layered double hydroxide reduction soil remediation