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Stability mechanism and control of the pumpable supports in longwall recovery room

International Journal of Mining Science and Technology 2024年第7期34卷 957-974页

作者： Dong Zhang Jianbiao bai Zhijun Tian Zizheng Zhang Yonghong Guo Rui Wang Ying Xu Hao Fu Shuai Yan Min Deng Shuaigang liu State Key laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China Key laboratory of Xinjiang Coal Resources Green Mining Xinjiang Key Laboratory of Coal-bearing Resources Exploration and ExploitationXinjiang Engineering Research Center of Green Intelligent Coal MiningXinjiang Institute of EngineeringUrumqi 830023China Work Safety Key laboratory on Prevention and Control of Gas and Roof Disasters for Southern Goal Mines Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal MinesHunan University of Science and TechnologyXiangtan 411201China School of Mines China University of Mining and TechnologyXuzhou 221116China

The load-bearing performance(lBP)of pumpable supports(PPS)is crucial for the stability of longwall pre-driven recovery room(PRR)surrounding ***,the unbalanced bearing coefficient(UBC)of the PPS(undertaking unequal load along the mining direction)has not been investigated.A mechanical model of the PRR was established,considering the main roof cantilever beam structure,to derive an assessment formula for the load,the failure criteria,and the UBC of the ***,the generation mechanisms,and influencing factors of the UBC were *** sensitivity analysis shows that the main roof hanging length(l_(2))and the spacing between the PPS(r)significantly impact the UBC.A novel design of the PPS and the coupling control technology were proposed and applied to reduce the UBC of the PPS in the adjacent longwall *** results showed no failure of the PPS at the test site,with the UBC(ζ)reduced to 1.1 consistent with the design value(1.15)basically,fully utilizing the collaborative lBP of the ***,the maximum roof-to-floor convergence of the PRR was 234 mm,effectively controlling the stability of the surrounding rock of the PRR and ensuring the mining equipment recovery.

关键词： Pre-driven recovery room Pumpable supports Unbalanced bearing coefficient Hydraulic fracture Stability analysis Surrounding rock control

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一种抗遮掩的卫星视频目标跟踪算法

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武汉大学学报（信息科学版） 2024年第9期49卷 1586-1596页

作者：吕京国白颖奇王琛北京建筑大学测绘与城市空间信息学院北京100044

卫星视频中的目标极易受到背景遮挡与淹没,造成外观特征匮乏,最终导致跟踪失败。以全卷积孪生网络为基础,提出一种抗遮掩的卫星视频目标跟踪算法,解决不同遮掩程度下运动目标的跟踪丢失问题。目标轻度遮掩时,以模板更新网络得到的前向... 详细信息

卫星视频中的目标极易受到背景遮挡与淹没,造成外观特征匮乏,最终导致跟踪失败。以全卷积孪生网络为基础,提出一种抗遮掩的卫星视频目标跟踪算法,解决不同遮掩程度下运动目标的跟踪丢失问题。目标轻度遮掩时,以模板更新网络得到的前向结果作为当前帧的跟踪结果,并将前向结果设为新的前向模板,获取运动目标的变化特征。目标重度遮掩时,首先,将前向结果设为新的后向模板,利用后向模板对上一帧影像中的目标进行再次跟踪;然后,采用空间位置预测模块获取目标的历史轨迹特征,得到轨迹结果;最后,以再次跟踪得到的双向验证误差为依据,将前向结果和轨迹结果相结合,得到当前帧的跟踪结果。以吉林一号卫星视频数据为例,利用典型运动目标进行算法验证。结果表明,所提算法可以在目标遮掩时提供较为准确的跟踪结果,跟踪精确率与成功率分别达到76.2%和78.9%,算法跟踪速度为33帧/s。所提算法可以实现遮掩情况下运动目标的持续跟踪与监测,实际应用中能够有效提高智能交通、防灾救灾、战时监控等方面的应急处理能力。

关键词：卫星视频数据目标跟踪遮掩变化特征双向验证误差

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Experimental Study on Gas Flow Uniformity in a Diesel Particulate Filter Carrier

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Fluid Dynamics & Materials Processing 2024年第1期20卷 193-204页

作者： Zhengyong Wang Jianhua Zhang Guoliang Su Peixing Yang Xiantao Fan Shuzhan bai Ke Sun Guihua Wang School of Energy and Power Engineering Shandong UniversityJinan250061China State Key laboratory of Engines Tianjin UniversityTianjin300072China Weichai Power Emission Solutions Technology Company limited Weifang261043China China·Shandong·YYO Emission Control System Co. Ltd.Liaocheng252100China

A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products *** using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relatively high local temperatures,potentially resulting in damage to the carrier;On the other hand,the internal temperature field can also undergo significant changes contributing to increase this *** study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle(DTI)condition by means of bench *** is shown that the considered silicon carbide carrier exhibits good flow uniformity,with a temperature deviation of no more than 2%with respect to the same radius measurement point at the outlet during the regeneration *** the DTI test,the temperature is relatively high within r/2 near the outlet end,where the maximum temperature peak occurs,and the maximum radial temperature gradient is located between r/2 and the *** these quantities grow as the soot load increases,thereby making the risk of carrier burnout ***,it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/l,which reduces the frequency of active regeneration by approximately 40%compared to a cordierite DPF.

关键词： DPF flow uniformity DTI silicon carbide carrier soot load

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Depletion of squalene epoxidase in synergy with glutathione peroxidase 4 inhibitor RSl3 overcomes oxidative stress resistance in lung squamous cell carcinoma

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Precision Clinical Medicine 2024年第2期7卷 109-121页

作者： Guo li lu Chen Hua bai li Zhang Jie Wang Weimin li CAMS Key laboratory of Translational Research on lung Cancer State Key Laboratory of Molecular OncologyDepartment of Medical OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences Peking Union Medical CollegeBeijing 100021China Department of Pulmonary and Critical Care Medicine West China HospitalSichuan UniversityChengdu 610041China Institute of Respiratory Health Frontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China Precision Medicine Center Precision Medicine Key Laboratory of Sichuan ProvinceWest China HospitalSichuan UniversityChengdu 610041China State Key laboratory of Respiratory Health and Multimorbidity West China HospitalChengdu 610041China The Research Units of West China Chinese Academy of Medical SciencesWest China HospitalChengdu 610041China

Background:lung squamous cell carcinoma(lusc)lacks effective targeted therapies and has a poor *** of squalene epoxidase(SQlE)has been implicated in metabolic disorders and ***,the role of SQlE as a monooxygenase involved in ***:We analyzed the expression and prognosis of lung adenocarcinoma(lUAD)and lUSC samples from GEO and TCGA *** proliferative activity of the tumors after intervention of SQlE was verified by cell and animal ***-1 assay,flow cytometry,and Western blot were used to show changes in apoptosis after intervention of *** cytometry and fluorescence assay of ROs levels were used to indicate oxidative stress ***:We investigated the unique role of SQlE expression in the diagnosis and prognosis prediction of *** of SQlE or treatment with the SQlE inhibitor terbinafine can suppress the proliferation of lUsC cells by inducing apoptosis and reactive oxygen species ***,depletion of SQlE also results in the impairment of lipid peroxidation and ferroptosis resistance such as upregulation of glutathione peroxidase ***,prevention of SQlE in synergy with glutathione peroxidase 4 inhibitor RSl3 effectively mitigates the proliferation and growth of ***:Our study indicates that the low expression of sQlE employs adaptive survival through regulating the balance of apoptosis and ferroptosis *** future,the combinational therapy of targeting sQlE and ferroptosis could be a promising approach in treating lUSC.

关键词： lung squamous cell carcinoma squalene epoxidase terbinafine RoS ferroptosis

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1-甲氧基-9,10-双(苯乙炔基)蒽的合成

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精细化工 1999年第2期16卷 51-53页

作者：李斌苗蔚荣程侣柏大连理工大学精细化工(染料表面活性剂)国家重点实验室辽宁大连116012

由１－硝基蒽醌与甲酸钠作用生成１－甲氧基蒽醌，收率７５％。１．甲氧基蒽醌与苯乙炔基溴化镁在ＴＨＦ中回流２４ｈ，水解后的混合物不经分离直接与氯化亚锡的乙酸溶液反应３０ｍｉｎ，一步法合成了题示化合物，收率４６％。

关键词：甲氧基苯乙炔基蒽染料发光材料

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Water temperature governs organophosphate ester dynamics in the aquatic food chain of Poyang lake

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Environmental Science and Ecotechnology 2024年第5期21卷 197-207页

作者： Zhenfei Yan Chenglian Feng Yiping Xu Jindong Wang Nannan Huang Xiaowei Jin Fengchang Wu Yingchen bai State Key laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China College of Environment Hohai UniversityNanjing210098China Key laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China China National Environmental Monitoring Centre Beijing100012China

Organophosphate esters(OPEs)are increasingly recognized as pervasive environmental contaminants,primarily from their extensive application in flame retardants and *** their widespread presence,the intricacies of OPE bioaccumulation within aquatic ecosystems remain poorly understood,particularly the environmental determinants influencing their distribution and the bioaccumulation dynamics across aquatic food *** we show that water temperature plays a crucial role in modulating the dispersion of OPE in the aquatic environment of Poyang *** quantified OPE concentrations across various matrices,uncovering levels ranging from 0.198 to 912.622 ng l^(-1) in water,0.013e493.36 ng per g dry weight(dw)in sediment,0.026e41.92 ng per g wet weight(ww)in plankton,0.13e2100.72 ng per g dw in benthic invertebrates,and 0.31e3956.49 ng per g dw in wild fish,highlighting a pronounced bioaccumulation ***,the intestines emerged as the principal site for OPE absorption,displaying the highest concentrations among the seven tissues *** the various OPEs,tris(chloroethyl)phosphate was distinguished by its significant bioaccumulation potential within the aquatic food web,suggesting a need for heightened *** propensity for OPE accumulation was markedly higher in benthic invertebrates than wild fish,indicating a differential vulnerability within aquatic *** study lays a foundational basis for the risk assessment of OPEs as emerging contaminants and underscores the imperative to prioritize the examination of bioaccumulation effects,particularly in benthic invertebrates,to inform future environmental safeguarding strategies.

关键词： Organophosphate esters Driving factor Bioaccumulation and biomagnification Ecological risk

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Design and parameters optimization of the curved sieve for an air suction jujube harvester

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 132-139页

作者： Shenghe bai Yanwei Yuan Kang Niu liming Zhou Bo Zhao liguo Wei lijing liu Xuejun Zhang College of Engineering China Agricultural UniversityBeijing 100083China National Key laboratory of Agricultural Equipment Technology Chinese Academy of Agricultural Mechanization Sciences Group Co.Ltd.Beijing 100083China College of Mechanical and Electrical Engineering Xinjiang Agricultural UniversityUrumqi 830052China

In order to improve the screening performance and cleaning effect of the jujube harvesting machinery cleaning device,a vibrating curved screen device was designed in this *** analyzing the structure mechanism of the curved sieve body,it was obtained that the arc-shaped mesh hole spacing S was 15-25 mm and the curved mesh hole curvature U was 90°-150°.By exploring the movement state and stress of jujube and impurities on the curved sieve body,it was determined that the horizontal spacing l of the curved layer sieve was 30 mm and the vertical spacing H was 45-65 *** the vertical spacing H of the curved layer sieve,the curvature U of the curved mesh hole,and the spacing S of the curved mesh hole as the experimental factors,considering the screening efficiencyαand the impurity contentβof the jujube as the response values,the three-factor three-level quadratic regression orthogonal experiment was designed,establishing the regression mathematical model of each factor and response value,and the multiple target optimization algorithm of Design-expert software was used to optimize various *** results showed that the influence factors on the screening efficiency were in the descending order as:the arc screen spacing,the vertical spacing of the curved layer screen,and the curved screen hole curvature;The significant factors affecting the impurity content of jujube were in the descending order as:the arc screen spacing,the curved screen hole curvature,and the vertical spacing of the curved layer *** experimental results were verified by the optimized combination of parameters:when the vertical spacing H of the curved layer screen was 65 mm,the curved screen hole curvature U was 110°,and the arc screen spacing S was 23 mm,the average screening efficiencyαin the test was 91.09%.The relative error between the experimental verification value and the theoretical optimization value was 1.36%,which was less than 5%.The impurity content of jujubeβin the test w

关键词： jujube harvesting cleaning device curved sieve sieve structure conveying pipe mathematical model

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聚焦高斯涡旋光束焦区电场和磁场的偏振奇点

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物理学报 2014年第15期63卷 132-141页

作者：罗亚梅高曾辉唐碧华吕百达泸州医学院生物医学工程系泸州646000 宜宾学院计算物理重点实验室宜宾644000 四川大学激光物理与化学研究所成都610064

以高斯涡旋光束为例,研究了聚焦场中电场和磁场的偏振奇点变化规律.结果表明,高斯涡旋光束经透镜聚焦后,在焦区存在二维和三维电场和磁场的偏振奇点,其位置一般不重合.适当改变与焦面的距离以及光阑截断参数等出现圆偏振奇点的移动、产... 详细信息

以高斯涡旋光束为例,研究了聚焦场中电场和磁场的偏振奇点变化规律.结果表明,高斯涡旋光束经透镜聚焦后,在焦区存在二维和三维电场和磁场的偏振奇点,其位置一般不重合.适当改变与焦面的距离以及光阑截断参数等出现圆偏振奇点的移动、产生和湮没.不同二维和三维电场和磁场圆偏振奇点湮没所对应的各参数临界值不同.在二维电场中,几何焦面上会有V点的产生.

关键词：聚焦高斯涡旋光束电场和磁场的偏振奇点焦区

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The non-stationary and spatially varying associations between hand,foot and mouth disease and multiple environmental factors:A Bayesian spatiotemporal mapping model study

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Infectious Disease Modelling 2024年第2期9卷 373-386页

作者： li Shen Minghao Sun Mengna Wei Qingwu Hu Yao bai Zhongjun Shao Kun liu School of Remote Sensing and Information Engineering Wuhan UniversityWuhanHubei ProvinceChina Department of Infection Disease Control and Prevention Xi'an Center for Disease Control and PreventionXi'anShaanxiChina Department of Epidemiology Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthAir Force Medical UniversityXi'anShaanxi ProvinceChina

The transmission and prevalence of Hand,Foot and Mouth Disease(HFMD)are affected by a variety of natural and socio-economic environmental *** study aims to quantitatively investigate the non-stationary and spatially varying associations between various environmental factors and HFMD *** collected HFMD surveillance cases and a series of relevant environmental data from 2013 to 2021 in Xi'an,Northwest *** controlling the spatial and temporal mixture effects of HFMD,we constructed a Bayesian spatiotemporal mapping model and characterized the impacts of different driving factors into global linear,non-stationary and spatially varying *** results showed that the impact of meteorological conditions on HFMD risk varies in both type and magnitude above certain thresholds(temperature:30°C,precipitation:70 mm,solar radiation:13000 kJ/m^(2),pressure:945 hPa,humidity:69%).Air pollutants(PM_(2.5),PM_(10),NO_(2))showed an inverted U-shaped relationship with the risk of HFMD,while other air pollutants(O_(3),SO_(2))showed nonlinear ***,the driving effect of increasing temperature on HFMD was significant in the 3-year period,while the inhibitory effect of increasing precipitation appeared evident in the 5-year *** addition,the proportion of urban/suburban/rural area had a strong influence on HFMD,indicating that the incidence of HFMD firstly increased and then decreased during the rapid urbanization *** influence of population density on HFMD was not only limited by spatial location,but also varied between high and low *** road density inhibited the risk of HFMD,but higher night light index promoted the occurrence of *** findings further demonstrated that both ecological and socioeconomic environmental factors can pose multiple driving effects on increasing the spatiotemporal risk of HFMD,which is of great significance for effectively responding to the changes in HFMD epidemic outbreaks.

关键词： Hand,foot,and mouth disease(HFMD) Environmental factors Bayesian spatiotemporal mapping model Non-stationary effects Spatially varying effects

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Enhanced detection of freeze‒thaw induced landslides in Zhidoi county(Tibetan Plateau,China)with Google Earth Engine and image fusion

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Advances in Climate Change Research 2024年第3期15卷 476-489页

作者： Jia-Hui YANG Yan-Chen GAO lang JIA Wen-Juan WANG Qing-bai WU Francis ZVOMUYA Miles DYCK Hai-long HE College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Soil Science University of Manitob1Winnipeg MB R3T 2N2Canada Department of Renewable Resources University of Albert1Edmonton AB T6G 2H1Canad

Freeze‒thaw induced landslides(FTIls)in grasslands on the Tibetan Plateau are a geological disaster leading to soil *** landslides reduce biodiversity and intensify landscape fragmentation,which in turn are strengthen by the persistent climate change and increased anthropogenic ***,conventional techniques for mapping FTIls on a regional scale are impractical due to their labor-intensive,costly,and time-consuming *** study focuses on improving FTIls detection by implementing image fusion-based Google Earth Engine(GEE)and a random forest *** of multiple data sources,including texture features,index features,spectral features,slope,and vertical‒vertical polarization data,allow automatic detection of the spatial distribution characteristics of FTIls in Zhidoi county,which is located within the Qinghai‒Tibet Engineering Corridor(QTEC).We employed statistical techniques to elucidate the mechanisms influencing FTIls *** enhanced method identifies two schemes that achieve high accuracy using a smaller training sample(scheme A:94.1%;scheme D:94.5%)compared to other methods(scheme B:50.0%;scheme C:95.8%).This methodology is effective in generating accurate results using only~10%of the training sample size necessitated by other *** spatial distribution patterns of FTIls generated for 2021 are similar to those obtained using various other training sample sources,with a primary concentration observed along the central region traversed by the *** results highlight the slope as the most crucial feature in the fusion images,accounting for 93%of FTIls occurring on gentle slopes ranging from 0°to 14°.This study provides a theoretical framework and technological reference for the identification,monitoring,prevention and control of FTIls in *** developments hold the potential to benefit the management of grassland ecosystem,reduce economic losses,and promote grassland sustainability.

关键词： Permafrost degradation Random forest Thaw slump Spatial distribution Tibetan Plateau

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