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A framework for dynamic modelling of railway track switches considering the switch blades,actuators and control systems

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Railway Engineering Science 2024年第2期32卷 162-176页

作者： sa.ka. dutta.tim ha.rison Christopher Ward Roger Dixon Phil Winship Institute of Thermofluids School of Mechanical EngineeringUniversity of LeedsLeedsWest YorkshireUK Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK Birmingham Centre for Railway Research and Education School of EngineeringUniversity of BirminghamBirminghamWest MidlandsUK Network Rail Milton KeynesBuckinghamshireUK

The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital *** is important because,globally,railway track switches are used to allow trains to change routes;they are a key part of all railway ***,because track switches are single points of failure and safety-critical,their inability to operate correctly can cause significant delays and concomitant *** order to better understand the dynamic behaviour of switches during operation,this paper has developed a full simulation twin of a complete track switch *** approach fuses finite element for the rail bending and motion,with physics-based models of the electromechanical actuator system and the control ***,it provides researchers and engineers the opportunity to explore and understand the design space around the dynamic operation of new switches and switch machines before they are *** is useful for looking at the modification or monitoring of existing switches,and it becomes even more important when new switch concepts are being considered and *** simulation is capable of running in real time or faster meaning designs can be iterated and checked *** paper describes the modelling approach,demonstrates the methodology by developing the system model for a novel“REPOINT”switch system,and evaluates the system level performance against the dynamic performance requirements for the *** the context of that case study,it is found that the proposed new actuation system as designed can meet(and exceed)the system performance requirements,and that the fault tolerance built into the actuation ensures continued operation after a single actuator failure.

关键词： Railway track switch Mathematical modelling Redundant actuation Finite element analysis

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Structural,optical,electrical,and dielectric relaxation properties of rare earth containing sodium bismuth titanate Na_(0.5)Bi_(0.5)TiO_(3) perovskite:Effect of ionic radius

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Journal of Rare Earths 2024年第2期42卷 383-391,I0006页

作者： Rajdip Roy Abhigyan dutta Department of Physics The University of BurdwanBurdwan713104India

The main focus of this work is to study the effect of the ionic radius of different rare earth dopant cations RE^(3+)(RE=La,Sm,Dy,and Ho) on structural and various physical properties of sodium bismuth titanate(Na_(0.5)B_(0.5)TiO_(3),NBT) based perovskite *** X-ray diffraction data indicate the successful formation of the rhombohedral phase(space group R3c) of NBT nano perovskite incorporated with various rare earth ions in *** lattice parameters were found to increase linearly with the ionic radius of the dopant *** ionic radii and atomic mass of rare earth dopants appear to be essential factors in the grain growth of the prepared *** grain growth results in better crystallinity of the sample by reducing the microstrain with the increase of dopant ionic *** emission scanning electron microscopy and energy-dispersive X-ray spectra confirm the prepared compositions' phase purity and *** UV-Vis spectra reveal that La-doped NBT composition exhibits the lowest optical band gap,which unfolds the application of NBT-based perovskite as photoactive *** ac conductivity and complex impedance spectra unveil that the composition with the largest ionic radius,i.e.,La-doped NBT compound,exhibits the highest dc and bulk conductivity with the lowest activation *** frequency-dependent dielectric data follows havriliak-Negami(HN) formalism and non-Debye type relaxation *** also indicate that La-doped NBT composition exhibits the highest dielectric strength ***,this study first elaborates that the increasing ionic radius of the rare earth dopant cation in the Bi-site of NBT perovskite improves its microstructural,optical,and electrical properties.

关键词： Rare earth doped NBT Microstructural analysis Optical band gap AC Conductivity Dielectric relaxation Rare earths

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Dry eye rate and its relationship with disease stage in patients with primary hypertension:a cross-sectional study in Vietnam

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 653-658页

作者： Tran Tat Thang Pham Hong Phuong Nguyen sa Huynh Nguyen Trung Kien NguyenDuy Toan Nguyen Thi Thu ha Le ha Khoa Nguyen Huu Dung Thai Doan Thang Le Viet Thang Nghe An Eye Hospital Nghe An 43000Vietnam Nghe An Friendship General Hospital Nghe An 43000Vietnam Military Hospital 103 Ha Noi 100000Vietnam Vietnam Military Medical University Ha Noi 100000Vietnam hanoi Medical University Ha Noi 100000Vietnam Bạch Mai Hospital Ha Noi 100000Vietnam TTH Vinh General Hospital Nghe An 100000Vietnam

AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary ***:A cross-sectional study included 432 patients with primary hypertension(with an equal number of patients in each group:144 in stage Ⅰ,Ⅱ,and Ⅲ hypertension)and 144 healthy subjects as a control *** Ocular Surface Disease Index(OSDI)and Schirmer Ⅰ test without anesthetics were conducted on all 576 *** with OSDI scoreshan in the control group(41.7%versus 18.8%;Phan those without DE,P<*** age,a long duration of hypertension,diabetes mellitus,elevated plasma creatinine,and CRP-hs levels were independent factors associated with DE in primary hypertension patients,P<***:DE is a common disorder associated with advanced age,a long duration of hypertension,diabetes mellitus,elevated plasma CRP-hs,and creatinine levels in patients with primary hypertension.

关键词： primary hypertension dry eye stage of hypertension plasma creatinine

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Novel insights in phosphodiesterase 4 subtype inhibition to target neuroinflammation and stimulate remyelination

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Neural Regeneration Research 2024年第3期19卷 493-494页

作者： Melissa Schepers tim Vanmierlo Department of Neuroscience Biomedical Research InstituteFaculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology School for Mental Health and NeuroscienceMaastricht UniversityMaastrichtNetherlands University MS Center(UMSC)hasselt-Pelt HasseltBelgium

In neurodegenerative and classically demyelinating disorders such as multiple sclerosis(MS),spinal cord injury(SCI),stroke,and Charcot-Marie-Tooth disease,glial functioning is compromised and nervous tissue integrity is ***,primary neurodegenerative disorders such as Alzheimer’s disease,amyotrophic lateral sclerosis(ALS),and Parkinson’s disease(PD)are increasingly linked to impaired oligodendroglia functioning upon *** to the destructive micro-environment created by nervous tissue damage,the progressive cellular loss in these disorders,and the amitotic nature of neurons,spontaneous endogenous repair process are limited in ***,there is a medical need for efficient therapeutic strategies capable of supporting neuro-reparative processes to occur,likely supported by improved oligodendroglia cell functioning.

关键词： impaired inflammation Marie

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Current state-of-the-art review of footwear–ground friction

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Friction 2024年第10期12卷 2188-2204页

作者： David REBENDA Tomáš SÁha Footwear Research Centre University InstituteTomas Bata University in ZlinZlin 76001Czech Republic Faculty of Mechanical Engineering Brno University of TechnologyBron 61600Czech Republic

The most important role of footwear is to ensure safe,functional walking,and foot *** the proper functionality of not only the work shoes,the anti-slip behavior of the shoe under various conditions and environments plays an important role in the prevention of slips,trips,falls,and consequent *** article is intended to review the current understanding of the frictional mechanisms between shoe outsoles and various counterfaces that impact the evaluation of outsole *** research focuses on the mechanisms driving outsole friction on different ground surfaces or the definition and description of parameters that influence outsole ***,the review discusses the effect of various surface contaminants on footwear ***,challenges and outlooks in the field of footwear outsoles are briefly mentioned.

关键词： shoe outsole composite slipperiness coefficient of friction(COF) adhesion safe walk

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Modelling rapid non-destructive test using light weight deflectometer on granular soils across different degrees of saturation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2732-2748页

作者： Javad Ghorbani Arooran Sounthararajah Troyee Tanu dutta Jayantha Kodikara ARC Smart Pavements Hub Dept.of Civil EngineeringMonash UniversityVIC3800Australia

This study introduces an advanced finite element model for the light weight deflectometer(LWD),which integrates contact mechanics with fully coupled *** simulating LWD tests on granular soils at various saturation levels,the model accurately reflects the dependence of the LWD modulus on dry density,water content,and effective *** model addresses and overcomes the limitations of previous finite element models for this specific ***,this research presents the first experimentally validated fully coupled contact impact ***,the research provides a comparative assessment of elastoplastic and nonlinear elastic models and contrasts an enriched node-tosegment method(developed in this study)with the more precise mortar technique for contact *** comparisons reveal unique advantages and challenges for each ***,the study underscores the importance of careful application of the LWD modulus,emphasising the need for sophisticated tools to interpret soil behaviour accurately.

关键词： Granular soils Plasticity Finite element analysis Contact mechanics Modulus Degree of saturation

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Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan DING Yao ha Zhong ZHONG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

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Synergic catalysis of W and Ni originating from substitution of trivacant phosphotungstate for the selective oxidation of aniline to azoxybenzene

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Chinese Chemical Letters 2024年第2期35卷 558-563页

作者： Sheng Cai Xiao-Yuan Wu Weiming Wu sa-sa Wang Can-Zhong Lu CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Xiamen Institute of Rare Earth Materials Chinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Partial substitution of polyoxometalate(POM)is an efficient route to modulate the catalytic property of maternal *** this work,a new Keggin type POM involving{Ni 6}cluster,{[Ni(H_(2)O)_(2)(Dach)_(2)][Ni(Dach)_(2)]_(2)}{[Ni_(6)Cl(μ-OH)_(3)(H_(2)O)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))][Ni_(6)(μ-OH)_(3)(H_(2)O)_(2)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))]}Cl·27H_(2)O,(1,Dach=1,2-diaminocyclohexane)was *** 1 shows excellent catalytic performance in the selective oxidation of aniline to azoxybenzene(AOB)in *** apparently different results from that with the matrix{PW_(9)O_(34)}({PW9})suggest the successful regulation of the catalytic property of{PW9}by the introduction of the{Ni6}cluster into the *** experimental results indicate that the highlighted performance of 1 is contributed by the synergy of W and Ni sites,which are respectively responsible for the oxidation and condensation steps in the production of *** good selectivity to AOB is essentially attributed to the effective modulation of the reaction rates of oxidation and condensation steps by W and Ni sites,respectively.

关键词： Polyoxometalate {Ni_(6)}cluster Modulated catalytic property Aniline oxidation Azoxybenzene

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Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil Manna Deepa Devapal Sharad Chandra Sharma Jyotsna dutta Majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT Mesra RanchiJharkhandIndia Department of Metallurgical and Materials Engineering IIT KharagpurWest BengalIndia Vikram sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron Microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： Mechanical milling Microstructure Process control agent(PCA) CoNiCrAIY Toluene Stearic acid Flowability

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High-resolution multi-scale air pollution system:Evaluation of modelling performance and emission control strategies

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Journal of Environmental Sciences 2024年第3期137卷 65-81页

作者： Diogo Lopes Joana Ferreira sandra Rafael ka In Hoi Xin Li Yuan Liu ka-Veng Yuen kai Meng Mok Ana Isabel Miranda Department of Environment and Planning&CEsaM University of AveiroAveiroPortugal Department of Civil&Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacao SARChina

A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization *** work aims to develop and test,a high-resolution multi-scale air pollution modelling system by integrating a set of adequate *** system is able to provide detailed air pollutant concentrations in urban areas and support air quality management strategies through a better identification of different atmospheric *** also allows furthering the design and assessment of air pollution control measures for a specific *** evaluate its performance and suitability,the system was applied to the Macao Special Administrative Region(saR),China,one of the most densely populated areas on earth,during a winter period when this area is affected by high levels of Particulate Matter(PM).Although the developed system tends to underestimate the PM concentrations,it revealed a good performance in reproducing the temporal and spatial air pollution *** exceedances of the Chinese air quality standards were calculated and high population exposure to PM pollution was *** tested urban atmospheric emission reduction scenarios have shown air quality improvements,indicating that emission reduction measures at urban level should focus on the domestic ***,it is crucial to implement joint pollution prevention strategies with neighbouring regions to improve the air quality in Macao *** approach developed in this work can support policymakers in defining new strategies to reduce atmospheric pollution in urban areas.

关键词： Urban areas High-resolution emission inventory Particulate matter Population exposure

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