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Synergistic Effect of the Planetary-scale Disturbance, Typhoon and Meso-β-scale Convective Vortex on the Extremely Intense Rainstorm on 20 July 2021 in Zhengzhou 被引量:3
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作者 Guanshun ZHANG Jiangyu MAO +5 位作者 Wei HUA Xiaofei WU Ruizao SUN Ziyu YAN Yimin LIU Guoxiong WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期428-446,共19页
On 20 July 2021,northern Henan Province in China experienced catastrophic flooding as a result of an extremely intense rainstorm,with a record-breaking hourly rainfall of 201.9 mm during 0800–0900 UTC and daily accum... On 20 July 2021,northern Henan Province in China experienced catastrophic flooding as a result of an extremely intense rainstorm,with a record-breaking hourly rainfall of 201.9 mm during 0800–0900 UTC and daily accumulated rainfall in Zhengzhou City exceeding 600 mm(“Zhengzhou 7.20 rainstorm”for short).The multi-scale dynamical and thermodynamical mechanisms for this rainstorm are investigated based on station-observed and ERA-5 reanalysis datasets.The backward trajectory tracking shows that the warm,moist air from the northwestern Pacific was mainly transported toward Henan Province by confluent southeasterlies on the northern side of a strong typhoon In-Fa(2021),with the convergent southerlies associated with a weaker typhoon Cempaka(2021)concurrently transporting moisture northward from South China Sea,supporting the rainstorm.In the upper troposphere,two equatorward-intruding potential vorticity(PV)streamers within the planetary-scale wave train were located over northern Henan Province,forming significant divergent flow aloft to induce stronger ascending motion locally.Moreover,the converged moist air was also blocked by the mountains in western Henan Province and forced to rise so that a deep meso-β-scale convective vortex(MβCV)was induced over the west of Zhengzhou City.The PV budget analyses demonstrate that the MβCV development was attributed to the positive feedback between the rainfall-related diabatic heating and high-PV under the strong upward PV advection during the Zhengzhou 7.20 rainstorm.Importantly,the MβCV was forced by upper-level larger-scale westerlies becoming eastward-sloping,which allowed the mixtures of abundant raindrops and hydrometeors to ascend slantwise and accumulate just over Zhengzhou City,resulting in the record-breaking hourly rainfall locally. 展开更多
关键词 extreme rainstorm potential vorticity trajectory tracking planetary-scale disturbance meso-β-scale convective system
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Geological suitability of natural sponge body for the construction of sponge city——a case study of Shuanghe Lake district in Zhengzhou airport zone 被引量:1
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作者 Yong-jun Su Hui Tang +4 位作者 Ai-min Wu Xue-ping Dai Shuang Liu Hong-wei Liu Heng Kuang 《Journal of Groundwater Science and Engineering》 2023年第2期146-157,共12页
Natural and geological environmental conditions have an important impact on the planning and construction of sponge cities.This paper analyzes geological factors that influence the usage of natural sponge bodies,takin... Natural and geological environmental conditions have an important impact on the planning and construction of sponge cities.This paper analyzes geological factors that influence the usage of natural sponge bodies,taking the Shuanghe lake district of Zhengzhou airport zone as an example.An evaluation system with seven factors has been established and the weights of these factors are determined using the analytic hierarchy process(AHP)method.Overlay analysis is then carried out on all factors using GIS to evaluate the geological suitability of the construction of the sponge city.The results show that geologically suitable area for city construction in Shuanghe lake district accounts for 12.3%,relatively suitable area accounts for 76.1%,and relatively unsuitable area accounts for 11.6%.For suitable and relatively suitable areas,we should make full use of the advantages of surface infiltration,vadose zone transportation and aquifer storage to build a sponge city infrastructure with geological engineering as the main component,supplemented by engineering measures such as surface water storage and drainage,and jointly establish a sustainable urban hydrological cycle.For less suitable areas,artificial rain and flood control works,such as roof garden,should be considered.The findings of this paper can serve as an important reference for sponge city planning and construction not only in the research area but also in other regions with similar geological conditions. 展开更多
关键词 Natural sponge bodies Low impact development Rain flood control Hierarchy analysis
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Evaluation of the Protection and Utilization of Great Sites:A Case Study of Zhengzhou City
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作者 Yi ZHOU Lijuan QIAN Jing XIAO 《Meteorological and Environmental Research》 CAS 2023年第4期50-52,55,共4页
The protection and utilization of great sites not only are related to the inheritance of historical and cultural heritage and academic research,but also directly affect local economic development and social and cultur... The protection and utilization of great sites not only are related to the inheritance of historical and cultural heritage and academic research,but also directly affect local economic development and social and cultural dissemination.In this paper,five major great sites in Zhengzhou City(Dahe Village Site,Zhengzhou Shangcheng Site,Xiaoshuangqiao Site,the Capital of Zheng and Han States,and Mausoleum of Song Dynasty Tombs of Song Emperors)are taken as research objects,and a set of index system for evaluating the protection and utilization of great sites is constructed.A comprehensive evaluation is conducted from seven aspects:protection management,research value,site utilization,cultural value dissemination,socio-economic benefits,utilization effects,and regional development coordination.This paper provides a comprehensive and scientific evaluation perspective for the protection and utilization of great sites,which helps to better grasp the direction of site protection and utilization,and develop more practical and effective strategies for site protection and utilization. 展开更多
关键词 Great site Protection and utilization Utilization evaluation
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Comprehensive suitability evaluation of urban geological environment in Zhengzhou-Kaifeng area 被引量:2
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作者 CUI Zhen YANG Po ZHANG Zheng 《Journal of Groundwater Science and Engineering》 2016年第3期204-212,共9页
Suitability evaluation of urban geological environment is an important basic work in city planning and construction. With Zhengzhou-Kaifeng area as the research area, this paper discusses AHP and fuzzy comprehensive e... Suitability evaluation of urban geological environment is an important basic work in city planning and construction. With Zhengzhou-Kaifeng area as the research area, this paper discusses AHP and fuzzy comprehensive evaluation methods to classify impact factors at different levels, makes a mixing evaluation of the basic factors and comprehensive factors so as to correct the uncertainty of the weight of the basic factors in the initial evaluation and establish the corresponding evaluation index system, and carries out urban geological environment suitability evaluation in study area. Furthermore, this paper partitions the suitability of the research area according to evaluation results into five zones. It puts forward opinions and suggestions for the construction of research area, which have certain practical significances. 展开更多
关键词 Zhengzhou-Kaifeng Geological environment Suitability evaluation Index system
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Identifying the Geography and Determinants of O2O Online Retailers in Megacity in Central China:A Case Study of Zhengzhou City 被引量:1
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作者 QI Jinghui NIU Shuwen +4 位作者 YE Chenxi WANG Luojia WEl Yongna WEN Yuzhao ZHAO Shuling 《Chinese Geographical Science》 SCIE CSCD 2021年第5期931-950,共20页
In recent years,O2O e-commerce,represented by online group-buying,has developed vigorously,which had significant impacts on urban commercial space.Zhengzhou City is a rising national central city in China,and its e-co... In recent years,O2O e-commerce,represented by online group-buying,has developed vigorously,which had significant impacts on urban commercial space.Zhengzhou City is a rising national central city in China,and its e-commerce development level is ahead,but relevant researches are rare.Therefore,the data of online retailers of Meituan.com was collected and combined with Baidu map and Baidu heat map data.Then,we adopted the methods such as spatial statistics and geodetector to explore the geography and determinants of O2O online retailers in Zhengzhou urban area.The main conclusions are 1)The spatial development of O2O online retailers is characterized by significant global high-value agglomeration.2)The agglomeration areas of different types of O2O online retailers are different.Most of them are concentrated in the old urban area within the Third Ring Road of Zhengzhou City,forming five comprehensive agglomeration areas.3)The areas with the high e-commerce development level are mainly concentrated in the northeast and southwest of the x-shaped region formed by the intersection of Lianyungang-Lanzhou and Beijing-Guangzhou railways.Erqi Square and Guomao 360 Plaza are at the highest development level,followed by Zhongyuan Wanda Plaza and Daxue Middle Road.The development level at other areas is relatively low.4)Zhengzhou’s O2O commercial pattern is highly dependent on physical business.The population distribution,especially the population distribution during the nightlife period,plays a vital role in its spatial development,followed by accessibility.The influences of physical distance are slightly larger than that of time cost,but the difference between them is little.In addition,travelling costs have the least impact.This paper could provide certain references for urban commercial planning. 展开更多
关键词 O2O online retailers geodetector kernel density spatial development Zhengzhou City China
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Trends of Urban Air Pollution in Zhengzhou City in 1996-2008 被引量:6
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作者 DU Xile LU Changhe +1 位作者 WANG Hairong MA Jianhua 《Chinese Geographical Science》 SCIE CSCD 2012年第4期402-413,共12页
Urban air pollution is a commonly concerned environmental problem in the world. Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strat... Urban air pollution is a commonly concerned environmental problem in the world. Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strategies. This study, using data from six monitoring stations in Zhengzhou City, analyzed the changing trend in concentrations of SO2, NOJNO2 and TSP/PM10 in 1996-2008, based on non-parametric Mann-Kendall test and Sen's slope estimator, and evaluated the comprehensive air pollution level using Multi-Pollutant Index (MPI). It was found that the concen- tration of each pollutant exceeded obviously the World Health Organization (WHO) guideline value, but the changing trend varied: SO2 and NO2 were significantly increased mainly due to an increase in coal consumption and vehicle number, while NOx, TSP and PM10 decreased. The air pollution was serious, and differed markedly among the three functional regions: it is the most severe in the Industrial and Residential Area (IRA), followed by the Transportation Hub and Business District (THBD), and then the High-tech, Cultural and Educational Area (HCEA). Different from NO2 concentration that had a similar change trend/rate among the function regions, the change rate of PM10 concentra- tion differed spatially, decreased much more obviously in THBD than other two regions. For the whole city, the com- prehensive air pollution level declined gradually, illustrating that the air quality in Zhengzhou was improved in the last decade. 展开更多
关键词 urban air pollution Mann-Kendall test Sen's method Multi-Pollutant Index (MPI) Zhengzhou
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Invasion Risk Assessment of Exotic Plant Praxelis clematidea in Zhengzhou
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作者 Li Wenzeng Wang Zhihong 《Plant Diseases and Pests》 CAS 2017年第2期43-46,共4页
To reduce the harms of plant invasion,the risk assessment for biological invasion of exotic species( including intentionally introduced species and accidentally introduced species) is particularly important. Through... To reduce the harms of plant invasion,the risk assessment for biological invasion of exotic species( including intentionally introduced species and accidentally introduced species) is particularly important. Through data review,investigation research and expert consultation,risk assessment system and standard for exotic species invasion in Zhengzhou region was established. Risk of Praxelis clematidea was assessed,in order to provide a reference for possible biological invasion of exotic plants in Zhengzhou. 展开更多
关键词 Plant invasion Risk assessment Praxelis clematidea Zhengzhou
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Water Environment Carrying Capacity of New Zhengdong District in Zhengzhou City
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作者 JIANG Lingyan LIU Lei ZHENG Bingguo 《Journal of Landscape Research》 2016年第2期35-36,共2页
Taking sections of the Dongfeng Canal, the Xionger River and the Wei River in New Zhengdong District for example, this paper applied water environment capacity to analyze the carrying capacity of surface water environ... Taking sections of the Dongfeng Canal, the Xionger River and the Wei River in New Zhengdong District for example, this paper applied water environment capacity to analyze the carrying capacity of surface water environment in the east development zone of the city. The analysis shows that carrying capacity of surface water environment in the study area is not good, carrying capacity of 3 studied waters for TP, BOD_5 and COD is approaching to the limit. New Zhengdong District, in terms of industrial structure, should promote the projects with less water consumption, less or no discharge of wastewater, and also should enhance the sewage treatment, improve recycling rate of the reclaimed water, and reduce the negative impact of sewage and pollutant discharge on environment. 展开更多
关键词 Zhengzhou City Water environment carrying capacity Surface water environment
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Systemic analysis of pre-hospital trauma emergency treatment in Zhengzhou 被引量:3
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作者 Xiao-Peng Shi Li-Jie Qin +2 位作者 Yu-Xia Chang Fa-Liang Li Peng Wang 《Journal of Acute Disease》 2019年第1期34-37,共4页
Objective: To analyze the data of pre-hospital emergency treatment in zhengzhou from 2007 to 2016, and evaluate the current situation of pre-hospital trauma emergency treatment, in order to provide a scientific basis ... Objective: To analyze the data of pre-hospital emergency treatment in zhengzhou from 2007 to 2016, and evaluate the current situation of pre-hospital trauma emergency treatment, in order to provide a scientific basis for effective use of first aid resources and enhance success rate of trauma emergency treatment. Methods: Retrospective analysis was conducted based on pre-hospital emergency resources of Zhengzhou Emergency Medical Rescue Center from 2007 to 2016. Results: The total number of pre-hospital emergency treatment cases was 9305687 from 2007 to 2016 in Zhengzhou, of which 418882 were trauma cases. The top five causes of injury were traffic accident injury, cutting injury, beating injury, crushing injury and falling injury. The top five emergency treatments used were oxygen, hemostasis, dressing and fixation, fluid supplementation, analgesics and sputum aspiration. According to different directions of diagnosis, the pre-hospital emergency patients were divided into four groups:emergency treatment group, emergency observation group, admission to general ward group and admission to ICU group. There was no statistical difference in the ages among the four groups (P>0.05). There were significantly statistical differences in gender composition among the four groups, with more males than females (P<0.01). Significant statistical differences also showed in CRAMS scores among the four groups (P<0.01). Before and after the training of primary trauma care, there was no significant difference in the constituent ratio of the trauma (P>0.05), but the mortality of the trauma, the average arrival time, and the mean treatment time were significantly different (P<0.01). Conclusions: The number of pre-hospital emergency trauma patients increased year by year, but the constituent ratio changed little. CRAMS score is important for the patients triage. Through the training of primary trauma care, the constituent ratio of death was reduced, and the average treatment time was shortened. 展开更多
关键词 PRE-HOSPITAL FIRST AID TRAUMA CRAMS PRIMARY TRAUMA CARE
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Planning and Design of Zhengzhou Forest Park Based on Natural Ecological Experience 被引量:2
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作者 TANG Zhenxing CHEN Qunyang 《Journal of Landscape Research》 2013年第5期27-30,共4页
Through summarizing and analyzing planning objectives, landscape division and natural ecological experience planning of Zhengzhou Forest Park, the authors discussed the application of human-nature harmony in the plann... Through summarizing and analyzing planning objectives, landscape division and natural ecological experience planning of Zhengzhou Forest Park, the authors discussed the application of human-nature harmony in the planning, stressed citizens' needs for experiencing natural ecological environment, and tried to build Zhengzhou Forest Park with picturesque scenery, complete facilities, and harmonious human-nature coexistence. 展开更多
关键词 LANDSCAPE architecture NATURAL ECOLOGICAL EXPERIENCE FOREST PARK Planning and design
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A Study on the Tectonic Characteristics of Shallow Faults in the East of Zhengzhou City
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作者 Zhao Chengbin Li Deqing +2 位作者 Zhao Jingyao Yuan Hongke Sun Zhenguo 《Earthquake Research in China》 2007年第3期245-254,共10页
Study on fault activity is a fundamental part of earthquake prediction and earthquake relief in big cities.In the active fault exploration in Zhengzhou,the spatial distribution,geological features and activity of the ... Study on fault activity is a fundamental part of earthquake prediction and earthquake relief in big cities.In the active fault exploration in Zhengzhou,the spatial distribution,geological features and activity of the Huayuankou fault,the Shangjie fault and the Xushui fault were determined using the seismic prospecting method.New understanding about the characteristics of the faults was gained.This provides reliable basic data for future earthquake forecast and earthquake relief work in Zhengzhou.In addition,we proposed some ways to identify fault activity through analyzing the characteristics of the activity of a fault and raised an effective method for exploring active faults in big cities and exploring concealed faults in regions covered with thick overburdens. 展开更多
关键词 Active fault Concealed fault Time section
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Comparison of Corneal Thickness of Young People with Middle and High Myopia between Shantou and Zhengzhou
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作者 Lixia Sun Yue Song +2 位作者 Riping Zhang Zhongren Zheng Yang Wang 《Eye Science》 CAS 2012年第1期41-43,共3页
Purpose:To compare the corneal thickness of young subjects (aged 18 to 30 years).with moderate and high myopia living in Shantou and Zhengzhou.Methods:One hundred and forty myopic subjects from Shantou (Guangdong,sout... Purpose:To compare the corneal thickness of young subjects (aged 18 to 30 years).with moderate and high myopia living in Shantou and Zhengzhou.Methods:One hundred and forty myopic subjects from Shantou (Guangdong,southern China) and 101 from Zhengzhou (Henan,central China)were selected and divided into 2 groups (moderate-myopic group and high-myopic group).The participants were sex-and age-matched.The central corneal thickness (CCT) and thinnest corneal thickness (TCT) were measured by Orbscan and compared between the two groups.Results:In the high-myopic group,CCT (515.47±40.39 μm) and TCT (510.22±40.95 μm) of the Shantou subjects (mean spherical equivalent.[SE]-7.56±1.35),were thinner than those of their Zhengzhou counterparts.(mean SE-7.47 ±0.88).In the moderate-myopic group.(Shantou mean SE-4.52 ±0.83;Zhengzhou-4.67 ± 0.77),CCT and TCT did not differ between the two cities.Conclusion:The corneal thickness of high-myopic eyes may differ between Shantou and Zhengzhou. 展开更多
关键词 膜厚度 汕头市 近视 郑州 年轻人 中国南方 中部地区 CCT
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Analysis of Influential element of Building Economy in Zhengzhou, Henan
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作者 Ren Huijun Li Longxing 《International Journal of Technology Management》 2013年第4期107-110,共4页
With the rapid development of Chinese society, building economy developped more and more rapidly and management job is increasingly onerous. In this paper, using rough set to Henan province Zhengzhou city building eco... With the rapid development of Chinese society, building economy developped more and more rapidly and management job is increasingly onerous. In this paper, using rough set to Henan province Zhengzhou city building economy undertakes an analysis, extracting the important attribute information and removing of miscellaneous information, getting restricting the building economy development influence factor, and analysis of building economy of the intrinsic law of development, the developers were reasonable guiding to promote business buildings and building economic development, helping government departments to carry out economic decisions. 展开更多
关键词 Rough Set theoretical approach building economy
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Characteristics of the Zhengzhou Laoyachen Fault Revealed by Seismic Exploration Data
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作者 Liu Baojin Zhao Chengbin +2 位作者 Tian Qinjian Liu Yaoxing Feng Shaoying 《Earthquake Research in China》 2009年第2期161-169,共9页
Exploration and research of fault activities are the fundamentals of earthquake prediction and prevention and disaster reduction. In order to determine the location, characteristics and activities of the Zhengzhon-Lao... Exploration and research of fault activities are the fundamentals of earthquake prediction and prevention and disaster reduction. In order to determine the location, characteristics and activities of the Zhengzhon-Laoyachen fault, shallow seismic prospecting with different exploration depth across the Laoyachen fault was carried out in the northern suburbs of Zhengzhou city in 2006. The images of the subterranean structure and tectonics at depths of 30m- 6000m have been available by applying the combined methods of explosive seismic sources and vibrator seismic sources, as well as the combination of diverse observation systems with different parameters. The outcome indicates that the Laoyachen fault is a normal fault running NW and dipping NE, which offsets stratums ahead of Neogene (N). However, no fault displacements are found in the interior stratums of Q + N. 展开更多
关键词 Laoyachen Fault Shallow seismic exploration Fault activity S/N
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The impact of social capital on children's (6–12) use of ICT in urban communities: A field survey from Zhengzhou City, Henan Province
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作者 Ping WANG Shang HUANG +1 位作者 Miao MIAO Tingting LI 《Chinese Journal of Library and Information Science》 2015年第4期50-61,共12页
Purpose: This paper focuses on the impact of social capital on urban children's use behavior of information communication technology (ICT).Design/methodology/approach: Using the field survey and in-depth intervie... Purpose: This paper focuses on the impact of social capital on urban children's use behavior of information communication technology (ICT).Design/methodology/approach: Using the field survey and in-depth interviews, we interviewed 40 children aged 6 to 12 and their parents from a staff residential quarter of the Zhengzhou University--"Shengheyuan" community (SHY), and a commercial residential quarter--"Wanfenghuicheng" community (WFHC) in the high-tech zone of Zhengzhou City, Henan Province. We used the social capital theory to analyze the interviewees' record.Findings: In urban communities, social capital is the most important factor for children (aged 6 to 12) in their ICT use. Our findings indicate that children in families with higher levels of social capital, such as internal resources, family income, parent educational backgrounds and parents' social network, have more-highly developed ICT skills. Personal motivation and obstacles, such as lack of access to computers on a regular basis, also have an impact on children's ICT use. External social capital, including schools, libraries, and public service institutes, have little impact on children's ICT use, if not combined with internal social capital factors.Research limitations: Our research samples were collected from two communities within the same city, which may influence the generalization of this research result.Originality/value: To explore the social capital's influence on children's ICT use, we used field observation for ICT use of children aged 6 to 12 in urban communities in China, and studied the children's ICT behavior from the perspective of internal and external social capital. 展开更多
关键词 Social capital Children aged 6 to12 Information communication technology Field observation Community informatics
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High Temperature Ceramics Institute (HTCI) Zhengzhou University (ZZU), China
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作者 YEFangbao 《China's Refractories》 CAS 2005年第1期28-29,共2页
Zhengzhou University is one of the national key universities in China and is jointly supported by the Ministry of Education and Henan Provincial Government. It is located in Zhengzhou city, capital of Henan province i... Zhengzhou University is one of the national key universities in China and is jointly supported by the Ministry of Education and Henan Provincial Government. It is located in Zhengzhou city, capital of Henan province in central China which is the cradle of Chinese culture. The university campus covers an area of 4.3 million m2. There are 40 thousand undergraduate and 3600 post-graduate students. Its ceramics department enrolls about 350 students. 展开更多
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Raindrop Size Distributions in the Zhengzhou Extreme Rainfall Event on 20 July 2021:Temporal-Spatial Variability and Implications for Radar QPE
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作者 Liman CUI Haoran LI +4 位作者 Aifang SU Yang ZHANG Xiaona LYU Le XI Yuanmeng ZHANG 《Journal of Meteorological Research》 SCIE CSCD 2024年第3期489-503,共15页
In this study,a regional Parsivel OTT disdrometer network covering urban Zhengzhou and adjacent areas is employed to investigate the temporal-spatial variability of raindrop size distributions(DSDs)in the Zhengzhou ex... In this study,a regional Parsivel OTT disdrometer network covering urban Zhengzhou and adjacent areas is employed to investigate the temporal-spatial variability of raindrop size distributions(DSDs)in the Zhengzhou extreme rainfall event on 20 July 2021.The rain rates observed by disdrometers and rain gauges from six operational sites are in good agreement,despite significant site-to-site variations of 24-h accumulated rainfall ranging from 198.3 to 624.1 mm.The Parsivel OTT observations show prominent temporal-spatial variations of DSDs,and the most drastic change was registered at Zhengzhou Station where the record-breaking hourly rainfall of 201.9 mm over 1500-1600 LST(local standard time)was reported.This hourly rainfall is characterized by fairly high concentrations of large raindrops,and the mass-weighted raindrop diameter generally increases with the rain rate before reaching the equilibrium state of DSDs with the rain rate of about 50 mm h^(−1).Besides,polarimetric radar observations show the highest differential phase shift(K_(dp))and differential reflectivity(Z_(dr))near surface over Zhengzhou Station from 1500 to 1600 LST.In light of the remarkable temporal-spatial variability of DSDs,a reflectivity-grouped fitting approach is proposed to optimize the reflectivity-rain rate(Z-R)parameterization for radar quantitative precipitation estimation(QPE),and the rain gauge measurements are used for validation.The results show an increase of mean bias ratio from 0.57 to 0.79 and a decrease of root-mean-square error from 23.69 to 18.36 for the rainfall intensity above 20.0 mm h^(−1),as compared with the fixed Z-R parameterization.This study reveals the drastic temporal-spatial variations of rain microphysics during the Zhengzhou extreme rainfall event and warrants the promise of using reflectivity-grouped fitting Z-R relationships for radar QPE of such events. 展开更多
关键词 extreme rainfall raindrop size distribution RADAR quantitative precipitation estimation(QPE)
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水利新质生产力:内涵解读、理论框架与实施路径 被引量:18
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作者 左其亭 秦西 马军霞 《华北水利水电大学学报(自然科学版)》 北大核心 2024年第3期1-8,共8页
在新一轮科技革命和产业变革的大背景下,新质生产力成为高质量发展的内在要求和重要着力点。为把加快发展新质生产力的部署要求落实到水利工作的全过程各方面,提出了水利新质生产力的概念及内涵,认为水利新质生产力是追求高科技、高效... 在新一轮科技革命和产业变革的大背景下,新质生产力成为高质量发展的内在要求和重要着力点。为把加快发展新质生产力的部署要求落实到水利工作的全过程各方面,提出了水利新质生产力的概念及内涵,认为水利新质生产力是追求高科技、高效能、高质量、符合新发展理念的先进水利生产力质态;提出了由指导思想、基本原则、理论基础、主要研究内容和支撑体系五部分组成的水利新质生产力理论框架,阐述了水利新质生产力的主要研究内容;并从工程、技术、制度和管理支撑四方面,提出了水利新质生产力的实施路径。为加快形成和发展水利新质生产力提供理论基础和路径参考。 展开更多
关键词 新质生产力 水利新质生产力 内涵解读 理论框架 实施路径
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基于机器学习的数据库系统参数优化方法综述 被引量:2
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作者 石磊 李天 +3 位作者 高宇飞 卫琳 李翠霞 陶永才 《郑州大学学报(工学版)》 北大核心 2024年第1期1-11,28,共12页
参数优化是影响数据库性能和适应性的关键技术,合理的参数配置对于保障数据库系统的高效运行至关重要,但由于参数较多且参数间具有强关联性,传统参数优化方法难以在高维连续的参数空间中寻找最优配置,机器学习的发展为解决这一难题带来... 参数优化是影响数据库性能和适应性的关键技术,合理的参数配置对于保障数据库系统的高效运行至关重要,但由于参数较多且参数间具有强关联性,传统参数优化方法难以在高维连续的参数空间中寻找最优配置,机器学习的发展为解决这一难题带来新的机遇。通过总结和分析相关工作,将已有工作按照发展时间和特性分为专家决策、静态规则、启发式算法、传统机器学习方法和深度强化学习方法。对数据库参数优化问题进行定义,并说明启发式算法在参数优化问题上的局限性。介绍基于传统机器学习的参数优化方法,包括随机森林、支持向量机、决策树等,描述机器学习方法解决参数优化问题的一般流程并给出一般实现。由于需要大量带标注的数据,传统机器学习模型在适应性和调优能力等方面存在不足。侧重介绍深度强化学习模型的工作原理,定义参数优化问题与深度强化学习模型的映射关系,比较基于深度强化学习的相关工作对数据库性能提升、模型训练时间和涉及的技术,描述基于深度神经网络构建和训练智能体的具体流程。最后,总结已有工作的特点,对当前机器学习在数据库参数优化方面的研究热点和发展方向进行展望,指出多粒度调优、自适应算法和自运维是未来的研究趋势。 展开更多
关键词 数据库系统 参数优化 性能优化 机器学习 强化学习 数据库运维
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不同气象条件对高油酸花生产量的影响 被引量:3
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作者 胡延岭 杨海棠 +8 位作者 李盼 于沐 石彦召 刘软枝 朱桢桢 韩艳红 郑晓川 赵利民 《中国油料作物学报》 CAS CSCD 北大核心 2024年第1期129-134,共6页
以河南、山东等5个花生主要产区培育的19个高油酸花生新品种为材料,于2019年~2021年连续3年在郑州种植,采集3年间花生关键生育期(6月~9月)的旬平均气温、旬降水量和旬日照时数等气象数据,结合各个品种的产量数据进行综合分析。研究结果... 以河南、山东等5个花生主要产区培育的19个高油酸花生新品种为材料,于2019年~2021年连续3年在郑州种植,采集3年间花生关键生育期(6月~9月)的旬平均气温、旬降水量和旬日照时数等气象数据,结合各个品种的产量数据进行综合分析。研究结果表明,不同的品种对于气温、降水量和日照时数的敏感程度不同,冀花16、冀花11对开花下针期的温度和日照时数比较敏感,该时期的异常高温会致使其产量明显下降。中花413、中花412和花育917的产量与旬降水量成显著负相关,耐涝程度较差。对品种的稳定性分析表明,开农1768、南充1704、冀农16、开选016、花育961、郑农花25、郑农花23、冀农11、花育633和1508G等10个高油酸品种为年际间稳定性较好的品种,研究结论为高油酸品种的培育及深入利用提供了指导。 展开更多
关键词 花生 高油酸 气象条件 产量
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