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Journal of Systems Science & Complexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN ben m Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem for n-dimensional systems and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull formed by the ***,the dynamics of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the communication network and collision avoidance among the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a numerical example.

关键词： multi-agent systems networked systems target fencing

A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction

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Control Theory and Technology 2024年第3期22卷 394-405页

作者： Chuanxiang Gao Xinyi Wang Xi Chen ben m.Chen Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongShatinNTChina

Unmanned aerial vehicles(UAVs)are emerging as a powerful tool for inspections and repair works in large-scale and unstructured 3D infrastructures,but current approaches take a long time to cover the entire *** using UAVs for inspections and repair works puts forward a requirement of improving time efficiency in large-scale and cluster *** paper presents a hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction to balance the workload and reduce the overall task completion *** proposed framework consists of two stages,the exploration stage and the exploitation stage,resolving the task in a sequential *** the exploration stage,the density map is developed to update global and local information for dynamic load-balanced area partition based on reconstructability and relative positions of UAVs,and the Voronoi-based planner is used to enable the UAVs to reach their best *** obtaining the global map,viewpoints are generated and divided while taking into account the battery capacity of each ***,a shortest path planning method is used to minimize the total traveling cost of these viewpoints for obtaining a high-quality *** experiments are conducted in both a simulated and real environment to show the time efficiency,robustness,and effectiveness of the proposed ***,the whole system is implemented in real applications.

关键词： multi-UAV Coverage path planning Infrastructure inspection and reconstruction

Intraocular pressure before and after capsulorhexis using two viscoelastic substances and two surgical approaches in enucleated porcine eyes

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1156-1160页

作者： Chiraz ben Abdallah Walter Sekundo markus SLadewig Daniel m.Handzel Augenzentrum Osthessen Fulda 36037Germany University Eye Hospital Philipps-University Marburg 35043Germany University Eye Hospital Philipps-University Campus FuldaFulda 36043Germany

AIm:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this ***:Prospective experimental WetLab study carried out on enucleated porcine *** was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss meditec AG,Germany;hydroxy propylmethylcellulosis(HPmC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the ***:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the *** use of different OVDs made no *** the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm *** difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD ***:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine *** use of different OVD has no significant influence on IOP drop.

关键词： cataract surgery ophthalmosurgical viscoelastic device intraocular pressure capsulorhexis enucleated porcine eye

Natural Convection of a Power-Law Nanofluid in a Square Cavity with a Vertical Fin

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Fluid Dynamics & materials Processing 2024年第9期20卷 2091-2108页

作者： Amira m’hadbi mohammed El Ganaoui Haïkel ben Hamed Amenallah Guizani Khalid Chtaibi LERmAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

Chalcogenide Ovonic Threshold Switching Selector

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Nano-micro Letters 2024年第5期16卷 1-40页

作者： Zihao Zhao Sergiu Clima Daniele Garbin robin Degraeve Geoffrey Pourtois Zhitang Song min Zhu National Key Laboratory of materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China University of Chinese Academy of Sciences Beijing 100029People’s Republic of China ImEC Kapedreef 75LeuvenBelgium

Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or *** Optane,commonly referred to as three-dimensional phase change memory,stands out as one of the most promising *** Optane with cross-point architecture is constructed through layering a storage element and a selector known as the ovonic threshold switch(OTS).The OTS device,which employs chalcogenide film,has thereby gathered increased attention in recent *** this paper,we begin by providing a brief introduction to the discovery process of the OTS ***,we summarize the key elec-trical parameters of OTS devices and delve into recent explorations of OTS materials,which are categorized as Se-based,Te-based,and S-based material ***,we discuss various models for the OTS switching mechanism,including field-induced nucleation model,as well as several carrier injection ***,we review the progress and innovations in OTS mechanism ***,we highlight the successful application of OTS devices in three-dimensional high-density memory and offer insights into their promising performance and extensive prospects in emerging applications,such as self-selecting memory and neuromorphic computing.

关键词： Non-volatile memory Ovonic threshold switch(OTS) Chalcogenide Selector

Relationship Between metabolic Fitness and Performance in Police Occupational Tasks

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Journal of Science in Sport and Exercise 2021年第2期3卷 179-185页

作者： Elisa F.D.Canetti J.Jay Dawes Phoebe H.Drysdale Robert Lockie Charlie Kornhauser Ryan Holmes ben schram.robin m.orr Faculty of Health Sciences and medicine Bond Institute of Health and SportBond University2 Promethean WayGold CoastQLD 4226Australia Tactical Research Unit Bond UniversityGold CoastQLD 4226Australia School of Kinesiology Applied Health and RecreationOklahoma State University183 Colvin Recreation CenterStillwaterOK 74078USA California State Fullerton 800 N.State College BlvdFullertonCA 92831-3599USA Colorado State Patrol LakewoodCOUSA

Purpose To determine the relationship between metabolic fitness test scores and performance in police occupational *** Retrospective data from 106 law enforcement officers who completed two metabolic fitness assessments[anaerobic:a 20-m (10-m and 20-m splits) sprint,aerobic:20 m multi-Stage Fitness Test (20 m-mSFT)]and three routine occupational tasks[1.22 m Fence jump (FJ),8.5 m Victim Drag (VD with 102.3 kg) and "Get-up" (GU)]were collected.A Person's cor-relation coefficient and a standard multiple regression were used to assess the relationship between and predictive ability of,respectively,the fitness tests scores and performance on occupational *** There was a significant positive correlation between the 10-m sprint scores and FJ (r=0.524,Pmilarly,the 20-m sprint scores were significantly and moderately correlated with FJ (r=0.573,P mately 40% of the performance in the occupational tasks *** mSFT fitness assessment had a small,albeit significant negative correlation with the three tasks:FJ (r=-0.360,Pmetabolic fitness correlated with faster performance in police officer occupational tasks,particu-larly ones of an anaerobic nature (*** maximal sprint tests).In addition to typical aerobic fitness conditioning,anaerobic fitness conditioning could be vital for optimal performance in physically demanding tasks required of police officer.

关键词： Police Occupational health Physical fitness Work performance Rehabilitation

Transverse momentum balance of dijets in Xe+Xe collisions at the LHC

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Nuclear Science and Techniques 2024年第7期35卷 137-146页

作者： Yao Li Shu-Wan Shen Sa Wang ben-Wei Zhang Key Laboratory of Quark&Lepton Physics(mOE)and Institute of Particle Physics Central China Normal UniversityWuhan430079China College of Science China Three Gorges UniversityYichang443002China Center for Astronomy and Space Sciences and Institute of modern Physics China Three Gorges UniversityYichang443002China Guangdong-Hong Kong Joint Laboratory of Quantum matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou510006China

We present a theoretical study of the medium modifications of the p_(T)balance (x_(J)) of dijets in Xe+Xe collisions at■.The initial production of dijets was carried out using the POWHEG+PYTHIA8 prescription,which matches the next-toleading-order (NLO) QCD matrix elements with the parton shower (PS) *** SHELL model described the in-medium evolution of nucleus–nucleus collisions using a transport *** theoretical results of the dijet xJin the Xe+Xe collisions exhibit more imbalanced distributions than those in the p+p collisions,consistent with recently reported ATLAS *** utilizing the Interleaved Flavor Neutralisation,an infrared-and-collinear-safe jet flavor algorithm,to identify the flavor of the reconstructed jets,we classify dijets processes into three categories:gluon–gluon (gg),quark–gluon (qg),and quark–quark (qq),and investigated the respective medium modification patterns and fraction changes of the gg,qg,and qq components of the dijet sample in Xe+Xe *** is shown that the increased fraction of qg component at a small x_(J)contributes to the imbalance of the dijet;in particular,the q_(1)g_(2)(quark-jet-leading) dijets experience more significant asymmetric energy loss than the g_(1)q_(2)(gluon-jet-leading) dijets traversing the *** comparing the■of inclusive,■ dijets in Xe+Xe collisions,we observe■.moreover,ρ_(Xe),P_(b),the ratios of the nuclear modification factors of dijets in Xe+Xe to those in Pb+Pb,were calculated,which indicates that the yield suppression of dijets in Pb+Pb is more pronounced than that in Xe+Xe owing to the larger radius of the lead nucleus.

关键词： Heavy-ion collisions Quark-gluon plasma Jet quenching Transverse momentum balance

Epidemiological and histopathological characteristics of thyroid carcinoma in a Tunisian health care center

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 37-42页

作者： maissa ben Thayer Fatma Khanchel Imen Helal Dorra Chiboub Hedhli Raoueh Ehsen ben Brahim Raja Jouini Aschraf Chadli-Debbiche Faculty of medicine of Tunis Tunis El Manar UniversityTunisTunisia Depatment of Pathology Habib Thameur's HospitalTunisTunisia Department of Otorhinolaryngology-Head and Neck surgery Habib Thameur's HospitalTunisTunisia

Background:Thyroid carcinoma(TC)accounts for almost 0.5%–1%of total *** incidence is increasing rapidly *** studies have drawn up the epidemiological profile of TC and its clinical and pathological ***,to date,no similar studies have been conducted in ***:To establish an epidemiological profile of TC in a Tunisian health care institute and to analyze its clinical and histopathological characteristics in our *** and methods:We present a retrospective study reviewing the cases of TC diagnosed in our institution in a 4-year ***:We collected a sample of 192 cases of *** consisted of 31 males and 161 females(83.8%)with a sex-ratio m/F of *** mean age was 46.4 *** thyroid carcinoma was the most frequent histological *** multifocality rate was 33.8%.The mean size of TC was 2.2±1.9 cm.60.9%of TC were staged pT1 and 20.3%had nodal *** thyroid microcarcinomas were noted in 37.5%of ***:Our results were consistent with those of the literature.A high proportion of pT1 and pN0 tumors were noted in our series,suggesting that TC's diagnosis and management was performed at an early stage of the disease in our *** addition,our study enabled us to notice the impact of the Coronavirus disease 19 crisis on the management of TC in our *** studies are needed to establish the epidemiological profile of TC in Tunisia and to assess its clinical and pathological features.

关键词： coronavirus disease 19 epidemiology papillary thyroid carcinoma papillary thyroid microcarcinoma pathology thyroid carcinoma

Experimental design of paraffin/methylated melamine-formaldehyde microencapsulated composite phase change material and the application in battery thermal management system

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Journal of materials Science & Technology 2024年第2期169卷 124-136页

作者： Que Huang Silong Wang Jichun He Dengji Xu Safaa NAbdou mohamed mIbrahim Shiqi Sun Yanjun Chen Handong Li ben Bin Xu Changcheng Liu Zeinhom m.El-Bahy Zhanhu Guo School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Institute of Advanced Energy materials and Systems North University of ChinaTaiyuan 030051China School of Resources and Safety Engineering Central South UniversityChangsha 410010China School of medical and BioInformation Engineering Northeastern UniversityShenyang 110819China Department of Chemistry Khurmah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

In order to maintain the optimal operating temperature of the battery surface and meet the demand for thermal storage technology,battery thermal management system based on phase change materials has attracted increasing *** this work,a kind of core-shell structured microcapsule was synthesized by an in-situ polymerization,where paraffin was used as the core,while methanol was applied to mod-ify the melamine-formaldehyde shell to reduce toxicity and improve thermal ***,three different types of heat conductive fillers with the same content of 10 wt.%,i.e.,nano-Al_(2)O_(3),nano-ZnO and carbon nanotubes were added,generating *** microcapsules were uniform,and were not affected by the thermal fillers,which were evenly dispersed *** composite sample with carbon nanotubes(10 wt.%)showed the highest thermal conductivity of 0.50 W/(m K)and latent heat of 139.64 J/***,according to the leakage testing and battery charge/discharge experiments,compared with Al_(2)O_(3)and ZnO,the addition of carbon nanotubes remarkably enhances the heat storage ability as latent heat from 126.98 J/g for the prepared sample with Al_(2)O_(3)and 125.86 J/g for the one with ZnO,then to 139.64 J/g,as well as dissipation performance as a cooling effect by decreasing the sur-face temperature of battery from 2%to 12%of microcapsule,composite sample with carbon nanotubes presents a broad application prospect in battery thermal management system and energy storage field.

关键词： microcapsule Phase change material Battery Carbon nanotube Safety

models to predict injury, physical fitness failure and attrition in recruit training: a retrospective cohort study

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military medical Research 2020年第4期7卷 391-400页

作者： robin m.orr Bruce S.Cohen Stephen C.Allison Lakmini Bulathsinhala Edward J.Zambraski mark Jaffrey Tactical Research Unit Bond University2 Promethean WayGold CoastRobinaQLD 4226Australia United States Army Research Institute for Environmental medicine NatickMA 01760USA Defence Science and Technology Group Port MelbourneVIC 3207Australia

Background:Attrition rate in new army recruits is higher than in incumbent *** the current study,we identified the risk factors for attrition due to injuries and physical fitness failure in recruit training.A variety of predictive models were ***:This retrospective cohort included 19,769 Army soldiers of the Australian Defence Force receiving recruit training during a period from 2006 to *** them,7692 reserve soldiers received a 28-day training course,and the remaining 12,077 full-time soldiers received an 80-day training *** data included anthropometric measures,course-specific variables,injury,and physical fitness *** regression was used to develop a variety of models to predict the rate of attrition due to injuries and physical fitness *** area under the receiver operating characteristic curve was used to compare the performance of the ***:In the overall analysis that included both the 28-day and 80-day courses,the incidence of injury of any type was 27.8%.The 80-day course had a higher rate of injury if calculated per course(34.3%vs.17.6%in the 28-day course),but lower number of injuries per person-year(1.56 vs.2.29).Fitness test failure rate was significantly higher in the 28-day course(30.0%vs.12.1%).The overall attrition rate was 5.2%and 5.0%in the 28-day and 80-day courses,*** fracture was common in the 80-day course(n=44)and rare in the 28-day course(n=1).The areas under the receiver operating characteristic curves for the course-specific predictive models were relatively low(ranging from 0.51 to 0.69),consistent with"failed"to"poor"predictive *** course-combined models performed somewhat better than the course-specific models,with two models having AUC of 0.70 and 0.78,which are considered"fair"predictive ***:Attrition rate was similar between 28-day and 80-day *** comparison to the 80-day full course,the 28-day course had a lower rat

关键词： military training Predictive modelling Risk management Soldier