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International Journal of Coal Science & Technology 2024年第1期11卷 31-41页

作者： Ayush Sahu Satish Sinha Haider Banka department of CSE IIT(ISM)DhanbadJharkhand826004India department of Sustainability Adani universityAhmedabadGujrat382421India

One of the most dangerous safety hazard in underground coal mines is roof falls during retreat *** falls may cause life-threatening and non-fatal injuries to miners and impede mining and transportation *** a result,a reliable roof fall prediction model is essential to tackle such *** parameters that substantially impact roof falls are ill-defined and intangible,making this an uncertain and challenging research *** National Institute for Occupational Safety and Health assembled a national database of roof performance from 37 coal mines to explore the factors contributing to roof *** acquired for 37 mines is limited due to several restrictions,which increased the likelihood of *** logic is a technique for coping with ambiguity,incompleteness,and ***,In this paper,the fuzzy inference method is presented,which employs a genetic algorithm to create fuzzy rules based on 109 records of roof fall data and pattern search to refine the membership functions of *** performance of the deployed model is evaluated using statistical measures such as the Root-Mean-Square Error,Mean-Absolute-Error,and coefficient of determination(R_(2)).Based on these criteria,the suggested model outperforms the existing models to precisely predict roof fall rates using fewer fuzzy rules.

关键词： Underground coal mining Roof fall Fuzzy logic Genetic algorithm

Research progress in friction stir processing of magnesium alloys and their metal matrix surface composites: Evolution in the 21^(st )century

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Journal of Magnesium and Alloys 2024年第6期12卷 2091-2146页

作者： Roshan Vijay Marode Tamiru Alemu Lemma Nabihah Sallih Srinivasa Rao Pedapati Mokhtar Awang Adeel Hassan department of Mechanical Engineering Universiti Teknologi PETRONASBandarSeri IskandarPerak 32610Malaysia department of Mechanical Engineering College of EngineeringThe University of Texas Permian BasinMidland-OdessaUnited States Mechanical Engineering department Universiti Teknologi BruneiBrunei

Rising concerns about climate change drive the demand for lightweight ***(Mg)alloys are highly valued for their low weight,making them increasingly important in various *** focusing on enhancing the characteristics of Mg alloys and developing their Metal Matrix Composites(MMCs)have gained significant attention worldwide over the past decade,driven by the global shift towards lightweight *** Stir Processing(FSP)has emerged as a promising technique to enhance the properties of Mg alloys and produce ***,FSP adapted to refine grain size from the micro to the nano level and accelerated the development of MMCs due to its solid-state nature and the synergistic effects of microstructure refinement and reinforcement,improving strength,hardness,ductility,wear resistance,corrosion resistance,and fatigue ***,producing defect-free and sound FSPed Mg and Mg-MMCs requires addressing several variables and their interdependencies,which opens up a broad range of practical *** existing reviews on individual FSP of Mg,its alloys,and MMCs,an attempt has been made to analyze the latest research on these three aspects collectively to enhance the understanding,application,and effectiveness of FSP for Mg and its *** review article discusses the literature,classifies the importance of Mg alloys,provides a historical background,and explores developments and potential applications of FSPed Mg *** focuses on novel fabrication methods,reinforcement strategies,machine and tool design parameters,material characterization,and integration with other methods for enhanced *** influence of process parameters and the emergence of defects are examined,along with specific applications in mono and hybrid composites and their microstructure *** study identifies promising reinforcement materials and highlights research gaps in FSP for Mg alloys and MMCs *** conclude

关键词： Magnesium alloys Friction stir processing Metal matrix composites Lightweight Surface modification

A New Approach for the Determination of Metronidazole Using Switchable Solvent Coupled with Au-MWCNTs-Modified Electrochemical Sensor

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Journal of Analysis and Testing 2024年第2期8卷 191-200页

作者： Siamak Kiani Shahvandi Mehrorang Ghaedi Hamid Ahmar Chemistry department Yasouj UniversityYasouj75918-74831Iran Chemistry department University of ZabolZabol98615-538Iran

In this work,a new liquid-phase microextraction method coupled with an electrochemical technique using a switchable solvent was proposed for the determination of *** extraction solvent used was dipropylamine(DPA),which exhibited switchable *** means that it can become miscible or immiscible when in contact with carboxylic acids in the aqueous *** metronidazole was then measured using a glassy carbon electrode that was modified with Au-multiwalled carbon nanotubes(MWCNTs).The eff ect of diff erent parameters such as the type and amount of trigger,the addition of salt,and the volume of extraction solvent on the e fficiency of switchable hydrophilic solvent-based liquid-phase microextraction(SHS-LPME)was investigated using the one-factor-at-a-time *** optimizing the conditions,the linear calibration curve was obtained in the concentration range of 0.005–250μmol/***,the limit of quantification(LOQ)of 0.005μmol/L and the limit of detection(LOD)of 0.0015μmol/L were obtained,respectively.

关键词： Switchable solvent Metronidazole Liquid-phase microextraction Electrochemical techniques

Enhanced air-coupled impact echo technique by phase analysis of signals from multiple sensors

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 297-310页

作者： Najjiya Almallah Nenad Gucunski New Jersey department of Transportation New Jersey 08625USA department of Civil&Environmental Engineering Rutgers University-New BrunswickNJ 08854USA

This paper presents an air-coupled impact echo(IE)technique that relies on the phase spectrum of the collected data to find the frequencies corresponding to the reflections from *** proposed technique takes advantage of the fact that the IE compression wave is not a propagating wave,but it is the 1st order symmetrical(S1)mode Lamb wave at zero group velocity(S1-ZGV).Therefore,it searches the phase spectra of the data collected by multiple sensors to locate the frequency corresponding to the lowest phase *** a result,the technique reduces the effect of propagating waves,including the direct acoustic wave and ambient *** is named the Constant Phase IE(CPIE).The performance of the CPIE is experimentally compared with the regular amplitude spectrum-based IE technique and two other multisensor IE *** CPIE shows a performance advantage,especially in a noisy environment.

关键词： nondestructive testing(NDT) nondestructive evaluation(NDE) bridge inspection bridge evaluation impact echo bridge delamination concrete bridge deck air-coupled sensing MEMS

Evolutionary genomics of climatic adaptation and resilience to climate change in alfalfa

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Molecular Plant 2024年第6期17卷 867-883页

作者： Fan Zhang Ruicai Long Zhiyao Ma Hua Xiao Xiaodong Xu Zhongjie Liu Chunxue Wei Yiwen Wang Yanling Peng Xuanwen Yang Xiaoya Shi Shuo Cao Mingna Li Ming Xu Fei He Xueqian Jiang Tiejun Zhang Zhen Wang Xianran Li Long-Xi Yu Junmei Kang Zhiwu Zhang Yongfeng Zhou Qingchuan Yang Institute of Animal Science Chinese Academy of Agricultural SciencesBeijing 100193China National Key Laboratory of Tropical Crop Breeding Shenzhen BranchGuangdong Laboratory of Lingnan Modern AgricultureKey Laboratory of Synthetic BiologyMinistry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518000China School of Grassland Science Beijing Forestry UniversityBeijing 100083China department of Agronomy and Horticulture University of Nebraska-LincolnLincolnNE 68583USA department of Crop and Soil Sciences Washington State UniversityPullmanWA 99163USA U.S.department of Agriculture-Agricultural Research service Plant Germplasm Introduction and Testing ResearchProsserWA 99350USA National Key Laboratory of Tropical Crop Breeding Tropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 571101China

Given the escalating impact of climate change on agriculture and food security,gaining insights into the evolutionary dynamics of climatic adaptation and uncovering climate-adapted variation can empower the breeding of climate-resilient crops to face future climate ***(Medicago sativa ***),the queen of forages,shows remarkable adaptability across diverse global environments,making it an excellent model for investigating species responses to climate *** this study,we performed population genomic analyses using genome resequencing data from 702 accessions of 24 Medicago species to unravel alfalfa’s climatic adaptation and genetic susceptibility to future climate *** found that interspecific genetic exchange has contributed to the gene pool of alfalfa,particularly enriching defense and stress-response *** introgression between *** ***(***)and alfalfa not only aids alfalfa’s climatic adaptation but also introduces genetic burden.A total of 1671 genes were associated with climatic adaptation,and 5.7%of them were introgressions from *** integrating climate-associated variants and climate data,we identified populations that are vulnerable to future climate change,particularly in higher latitudes of the Northern *** findings serve as a clarion call for targeted conservation initiatives and breeding *** also identified preadaptive populations that demonstrate heightened resilience to climate fluctuations,illuminating a pathway for future breeding ***,this study enhances our understanding about the local adaptation mechanisms of alfalfa and facilitates the breeding of climate-resilient alfalfa cultivars,contributing to effective agricultural strategies for facing future climate change.

关键词： Medicago local adaptation population genetics adaptive introgression genetic vulnerability alfalfa breeding

Hearing Loss and Cognitive Impairment Among Community-Dwelling Older Adults-Liaoning,Henan,and Guangdong Provinces,China,2019-2020

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China CDC weekly 2024年第32期6卷 816-820,I0003页

作者： Shige Qi Yuzhang Huang Liyuan Yang Haoyan Guo Ran An Lu Cui Han Zhang Jing Wu National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina department of Health Policy Management Johns Hopkins University Bloomberg School of Public HealthBaltimoreMDUSA Chengnan Community Health service Center of Changping District BeijingChina National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijingChina School of Public Health Capital Medical UniversityBeijingChina

Summary What is already known about this topic?Many studies have shown that hearing loss(HL)is a risk factor for cognitive decline and dementia,but there are still limited studies on this association among Chinese older *** is added by this report?Based on the results of pure-tone audiometry tests,HL is associated with cognitive impairment in communitydwelling older *** odds ratios(ORs)were 1.23(1.08–1.40)for mild HL,1.55(1.32–1.82)for moderate HL,and 1.87(1.47–2.39)for severe or profound *** are the implications for public health practice?Enhanced public awareness of hearing protection is important for preventing cognitive *** is advocated to promote the screening of HL and cognitive function assessment in elderly health examinations or management in primary care services.

关键词： hearing Guangdong Henan

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao Cao Jilai Yu the department of Electrical Engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

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Journal of Forestry Research 2024年第2期35卷 209-221页

作者： Antônio Carlos Vargas Motta Shizuo Maeda Valdécio dos Santos dos Santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior Ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa João Bosco Vasconcellos Gomes department of Soil Sciences and Agriculture Engineering Federal University of ParanáR.dos Funcionários1540.CuritibaParanáCEP 80035‑050Brazil Brazilian Agricultural Research Company Embrapa FlorestasEstr.da Ribeira–Br‑476Km 111–Parque Monte Castelo.ColomboParanáCEP 83411‑000Brazil United States department of Agriculture‑Agricultural Research service USDA-ARS National Soil Dynamics Laboratory411 South Donahue DriveAuburnAL 36832USA Reforestation Remasa Rodovia PR 170–Km 522.BiturunaParanáCEP 84640‑000Brazil Federal Institute of Southeast of Minas Gerais R.Luz Interior360.Juiz de ForaMinas Gerais CEP 36030‑713Brazil

Needle chlorosis(NC)in Pinus taeda *** in Brazil becomes more frequent after second and third harvest rotation *** a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on *** were analyzed for various elements and *** soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple *** symptoms started at needle tips,then extended toward the needle base with *** flush needles had longer portions with YNC than second flush needles *** from the lower crown also had more symptoms along their length than those higher in the *** were similar to those reported for *** chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of *** in various parent soils in Brazil.

关键词： Nutritional deficiency Forest management Soil depletion Pine foliar analysis Needle chlorosis

DC Traction Power Supply System Based on Modular Multilevel Converter Suitable for Energy Feeding and De-icing

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 649-659页

作者： Lingxi Hou Shuqing Zhang Yingdong Wei Xiaoqian Li Qirong Jiang Mingrui Li Weirui Li department of Electrical Engineering Tsinghua UniversityBeijing 100084China

A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel converter (MMC). The FBSM-MMC is a novel type of voltage source converter (VSC) and can directly control the output DC voltage and conduct bipolar currents, thus flexibly controlling the power flow of the urban rail transit catenary. The proposed topology can overcome the inherent disadvantages of the output voltage drop in the diode rectifier units, increase the power supply distance and reduce the number of traction substations. The flexible DC technology can coordinate multiple FBSM-MMCs in a wide area and jointly complete the bidirectional control of catenary power flow during the operation of the electric locomotive, so as to realize the local consumption and optimal utilization of the recovered braking energy of the train. In addition, the FBSM-MMCs can also adjust the output current when the locomotive is out of service to prevent the catenary from icing in winter. The working modes of the proposed topology are illustrated in detail and the control strategy is specially designed for normal locomotive operations and catenary de-icing. Simulation cases conducted by PSCAD/EMTDC validate the proposed topology and its control strategy.

关键词： DC traction power supply system de-icing for catenary energy feeding modular multilevel converter based on full-bridge submodules(FBSM-MMC) urban rail transit

Study of bending angle and shadow in a new Schwarzschild-like black hole affected by plasma and non-plasma mediums

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Chinese Physics C 2024年第5期48卷 309-318页

作者： Riasat Ali Tiecheng Xia Muhammad Awais Rimsha Babar department of Mathematics Newtouch Center for Mathematics of Shanghai UniversityShanghai 200444China department of Mathematics University of Engineering and Technology Lahore-54890Pakistan department of Mathematics GC University Faisalabad Layyah CampusLayyah-31200Pakistan

In this study,we analyze the models of the deflection angle of a new Schwarzschild-like black hole(BH)and employ the optical metric of the *** achieve this,we use the Gaussian curvature of the optical metric and the Gauss-Bonnet theorem,known as the Gibbons-Werner technique,to determine the deflection ***,we examine the deflection angle in the presence of a plasma medium and the effect of the plasma medium on the deflection *** deflection angle of the BH solution in the gauged super-gravity is computed using the Keeton-Petters *** the ray-tracing technique,we investigate the shadow of the corresponding BH and analyze the plots of the deflection angle and shadow to verify the influence of the plasma and algebraic thermodynamic parameters on the deflection angle and shadow.

关键词： new Schwarzschild-like black hole Gibbons-Werner and Keeton-Petters techniques deflection angle ray-tracing approach shadow