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An improved typhoon monitoring model based on precipitable water vapor and pressure

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Geodesy and Geodynamics 2024年第3期15卷 276-290页

作者： Junyu Li Haojie Li Lilong Liu Jiaqing Chen Yibin Yao Mingyun Hu Liangke Huang Fade Chen Tengxu Zhang lv zhou College of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541006China Guangxi Key Laboratory of Spatial Information and Geomatics Guilin 541006China Qinzhou Institute of Surveying and Mapping for Housing and Urban-Rural Development Co. Ltd.Qinzhou 535000China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China School of Resources and Environmental Science and Engineering Hubei University of Science and TechnologyXianning 437100China

The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movement of a typhoon in detail minutely and resulting in insufficient accuracy. Hence,based on PWV and meteorological data, we propose an improved typhoon monitoring mode. First, the European Centre for Medium-Range Weather Forecasts Reanalysis 5-derived PWV(ERA5-PWV) and the Global Navigation Satellite System-derived PWV(GNSS-PWV) were compared with the reference radiosonde PWV(RS-PWV). Then, using the PWV and atmospheric parameters derived from ERA5, we discussed the anomalous variations of PWV, pressure(P), precipitation, and wind speed during different typhoons. Finally, we compiled a list of critical factors related to typhoon movement, PWV and P. We developed an improved multi-factor typhoon monitoring mode(IMTM) with different models(i.e.,IMTM-I and IMTM-II) in different cases with a higher density of GNSS observation or only Numerical Weather Prediction(NWP) data. The IMTM was evaluated through the reference movement speeds of HATO and Mangkhut from the China Meteorological Observatory Typhoon Network(CMOTN). The results show that the root mean square(RMS) of the IMTM-I is 1.26 km/h based on ERA5-P and ERA5-PWV,and the absolute bias values are mostly within 2 km/h. Compared with the models considering the single factor ERA5-P/ERA5-PWV, the RMS of the IMTM-I is improved by 26.3% and 38.5%, respectively. The IMTM-II model manifests a residual of only 0.35 km/h. Compared with the single-factor model based on GNSS-PWV/P, the residual of the IMTM-II model is reduced by 90.8% and 84.1%, respectively. These results propose that the typhoon movement monitoring approach combining PWV and P has evident advantages over the single-factor model and is expected to supplement traditional typhoon monitoring.

关键词： Typhoon GNSS/ERA5 PWV Pressure Monitoring Improved model

Embedding Derivatives and Integration Operators on Hardy Type Tent Spaces

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Acta Mathematica Sinica,English Series 2022年第6期38卷 1069-1093页

作者： Mao Fa WANG lv zhou School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we completely characterize the positive Borel measuresμon the unit ball B_(n)such that the differential type operator R^(m)of order m∈N is bounded from Hardy type tent space HT_(q,α)^(p)(B_(n))into L^(s)(μ)for full range of p,q,s,α.Subsequently,the corresponding compact description of differential type operator R^(m)is also characterized.As an application,we obtain the boundedness and compactness of integration operator J_(g)from HT_(q,α)^(p)(B_(n))toHT_(s,β)^(t)(B_(n)),and the methods used here are adaptable to the Hardy spaces.

关键词： Embedding derivative integration operator Hardy type tent space Carleson measure

Refining the ERA5-based global model for vertical adjustment of zenith tropospheric delay

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Satellite Navigation 2022年第3期3卷 221-230,I0005页

作者： Ge Zhu Liangke Huang Yunzhen Yang Junyu Li lv zhou Lilong Liu College of Geomatics and Geoinformation Guilin University of TechnologyGuilin541004China College of Resources and Environment Beibu Gulf UniversityQinzhou535011China

Tropospheric delay is an important factor affecting high precision Global Navigation Satellite System(GNSS)positioning and also the basic data for GNSS atmospheric research.However,the existing tropospheric delay models have some problems,such as only a single function used for the entire atmosphere.In this paper,an ERA5-based(the fifth generation of European Centre for Medium-Range Weather Forecasts Reanalysis)global model for vertical adjustment of Zenith Tropospheric Delay(ZTD)using a piecewise function is developed.The ZTD data at 611 radiosonde stations and the MERRA-2(second Modern-Era Retrospective analysis for Research and Applications)atmospheric reanalysis data were used to validate the model reliability.The Global Zenith Tropospheric Delay Piecewise(GZTD-P)model has excellent performance compared with the Global Pressure and Temperature(GPT3)model.Validated at radiosonde stations,the performance of the GZTD-P model was improved by 0.96 cm(23%)relative to the GPT3 model.Validated with MERRA-2 data,the quality of the GZTD-P model is improved by 1.8 cm(50%)compared to the GPT3 model,showing better accuracy and stability.The ZTD vertical adjustment model with different resolutions was established to enrich the model's applicability and speed up the process of tropospheric delay calculation.By providing model parameters with different resolutions,users can choose the appropriate model according to their applications.

关键词： Piecewise function Vertical adjustment ZTD GNSS Tropospheric delay

An ERA5 tropospheric parameters-augmented approach for improving GNSS precise point positioning

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Geodesy and Geodynamics 2023年第5期14卷 467-476页

作者： Liangke Huang Feifan Liu Lijie Guo Guiwen Lan lv zhou Cheng Wang Lilong Liu College of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541006China Wuhan Changjiang Waterway Rescue and Salvage Bure Wuhan 430014China Guangxi Institute of Natural Resources Survey and Monitoring Nanning530023China

Precise Point Positioning(PPP) technology has developed into a potent instrument for geodetic positioning, ionospheric modeling, tropospheric atmospheric parameter detection, and seismic monitoring.As atmospheric reanalysis data products’ accuracy and spatiotemporal resolution have improved recently, it has become important to apply these products to obtain high-accuracy tropospheric delay parameters, like zenith tropospheric delay(ZTD) and tropospheric horizontal gradient. These tropospheric delay parameters can be applied to PPP to reduce the convergence time and to increase the accuracy in the vertical direction of the position. The European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5) atmospheric reanalysis data is the latest product with a high spatiotemporal resolution released by the European Center for Medium-Range Weather Forecasts(ECMWF). Only a few researches have evaluated the application of ERA5 data to Global Navigation Satellite System(GNSS)PPP. Therefore, this study compared and validated the ZTD products derived from ERA5 data using ZTD values provided by 290 global International GNSS Service(IGS) stations for 2016-2017. The results indicated a stable performance for ZTD, with annual average bias and RMS values of 0.23 cm and 1.09 cm,respectively. Further, GNSS observations for one week in each of the four seasons(spring: DOY 92-98;summer: DOY 199-205;autumn: DOY 275-281;and winter: DOY 22-28) from 34 multi-GNSS experiments(MGEX) stations distributed globally in 2016 were considered to evaluate the performance of ERA5-derived tropospheric delay products in GNSS PPP. The performance of ERA5-enhanced PPP was compared with that of the two standard GNSS PPP schemes(without estimated tropospheric horizontal gradient and with estimated tropospheric horizontal gradient). The results demonstrated that ERA5-enhanced GNSS PPP showed no significant improvement in the convergence times in both the Eastern(E) and Northern(N) directions, while the average convergence time over four weeks in the

关键词： Precise point positioning ERA5 atmospheric reanalysis data Multi-GNSS Tropospheric delay

Neurochemical mechanism of the gastrointestinal interdigestive migrating motor complex in rats with acute inflammatory stomach ache

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Neural Regeneration Research 2012年第27期7卷 2136-2143页

作者： Xiaoli Xu Qin Li lv zhou Liqiang Ru Department of Anatomy School of Medicine Jianghan University Wuhan 430056 Hubei Province China Department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei ProvinceChina Department of Physiology Institute of Basic Medical Science Chinese Academy of Medical Science Beijing 100005 China

The normal gastrointestinal interdigestive migrating motor complex cycle was interrupted, and paroxysmal contraction appeared after formaldehyde-induced stomach ache. Activities of nitric oxide synthase, acetylcholinesterase and vasoactive intestinal peptide neurons were significantly reduced, whereas activities of calcitonin gene-related peptide neurons were significantly increased in the pyloric sphincter muscular layer, myenteric nerve plexus and submucous nerve plexus. Electroacupuncture at Zusanfi （ST36） suppressed paroxysmal contraction in rats with formaldehyde-induced stomach ache, and neurons in the enteric nervous system were normal. These results indicated that nitrergic neurons, cholinergic neurons, vasoactive intestinal peptide neurons and calcitonin gene-related peptide neurons in the enteric nervous system may be involved in changes to the gastrointestinal interdigestive migrating motor complex following stomach ache, and that electroacupuncture can regulate this process.

关键词： pyloric sphincter inflammatory pain interdigestive migrating motor complex enteric nervoussystem electroacupuncture neural regeneration

融合改进鲸鱼算法解缠的梧州市地面沉降InSAR监测

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遥感信息 2024年第1期39卷 52-58页

作者：赵凤阳周吕魏玉业桂林理工大学土木与测绘工程系南宁530001 桂林理工大学测绘地理信息学院广西桂林541004

针对基于InSAR地面沉降研究中干涉图解缠易陷入局部最优及地面沉降影响因子较多且复杂的情况,提出了一种结合全局鲸鱼算法寻优的InSAR解缠方法并以广西壮族自治区梧州市为研究区,构建人类扰动指数,探索其2018—2023年地面沉降状况及分... 详细信息

针对基于InSAR地面沉降研究中干涉图解缠易陷入局部最优及地面沉降影响因子较多且复杂的情况,提出了一种结合全局鲸鱼算法寻优的InSAR解缠方法并以广西壮族自治区梧州市为研究区,构建人类扰动指数,探索其2018—2023年地面沉降状况及分析其驱动力因子。结果表明,改进鲸鱼优化算法从全局角度寻找枝切线最短路径,有效避免了陷入局部最优的问题。基于上述解缠方法获取了2018—2023年研究区地面沉降状况,并选取两个特征区域探究影响地面沉降的驱动力因子。经相关性分析,研究区地面沉降与城市扩张及重要交通枢纽建设密切相关,两个特征区域地面沉降速率与梧州市区建设用地面积的拟合优度R 2分别为0.9386和0.9842。本文研究结果可以为研究区城市规划建设及应急防灾提供决策支持。

关键词：地面沉降 SBAS-InSAR 人类扰动指数驱动力分析改进鲸鱼算法

含硼/磷/氮阻燃元素的棉用阻燃剂的制备及其应用

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纤维素科学与技术 2024年第2期32卷 34-39页

作者：王浩然吕洲青岛大学化学化工学院山东青岛266071

随着全球环保意识的增强,开发环保型磷系阻燃剂取代有毒卤素阻燃剂成为阻燃剂行业的迫切需求,由于多元素协同阻燃剂具有更有效的阻燃性能,因此构建磷硼氮多元素交联型阻燃剂成为了一个具有创新性的研究方向。文中尝试了将硼酸和六氯磷... 详细信息

随着全球环保意识的增强,开发环保型磷系阻燃剂取代有毒卤素阻燃剂成为阻燃剂行业的迫切需求,由于多元素协同阻燃剂具有更有效的阻燃性能,因此构建磷硼氮多元素交联型阻燃剂成为了一个具有创新性的研究方向。文中尝试了将硼酸和六氯磷腈等易得的原材料,在丙酮和水体系中合成了一种P-N-B协同阻燃的无卤棉用阻燃物,并对其性质进行了探究。结果表明,阻燃剂浓度为150 g/L,用氨水调节整理液pH值,烘焙温度为120℃,烘焙时间为6 min时,棉织物的残炭长度为5.4 cm,极限氧数值(LOI)提高至43.5%。

关键词：棉织物阻燃性能环保高效协同阻燃

Facing challenges： China＇s Cultural Heritage Conservation

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China & The World Cultural Exchange 2015年第2期81卷 30-33页

作者： lv zhou

碱水热法制备Ti_(3)C_(2)-Ag_(3)PO_(4)光催化剂及其光催化性能研究

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现代化工 2024年第7期44卷 156-160,168页

作者：徐竞帆周绿山沈琪熊信洁刘丹李颖张玉唐佳文四川文理学院化学化工学院四川达州635000

通过碱水热反应合成了Ti_(3)C_(2),并以其为载体制备了不同负载量的Ti_(3)C_(2)-Ag_(3)PO_(4)光催化剂。利用FT-IR、XRD、SEM、XPS等对光催化剂进行表征。结果表明,在240℃水热条件下,碱刻蚀法制备的Ti_(3)C_(2)为刻蚀程度较低的片层结... 详细信息

通过碱水热反应合成了Ti_(3)C_(2),并以其为载体制备了不同负载量的Ti_(3)C_(2)-Ag_(3)PO_(4)光催化剂。利用FT-IR、XRD、SEM、XPS等对光催化剂进行表征。结果表明,在240℃水热条件下,碱刻蚀法制备的Ti_(3)C_(2)为刻蚀程度较低的片层结构,同时材料中有微量的TiO_(2)存在,同时Ag_(3)PO_(4)以立方相的形式负载到Ti_(3)C_(2)载体表面。随着Ag_(3)PO_(4)负载量的增加,Ti_(3)C_(2)-Ag_(3)PO_(4)的光催化活性逐渐增大,在催化剂质量为0.01 g、反应时间为60 min时,Ti_(3)C_(2)-Ag_(3)PO_(4)-85%对亚甲基蓝的降解率达到95%。Ti_(3)C_(2)与Ag_(3)PO_(4)异质结的存在使其具有较强的电荷分离能力和优异的光催化性能。

关键词：碱水热法 Ti_(3)C_(2)-Ag_(3)PO_(4) 光催化