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Influence of regional background stress fields on the spontaneous rupture of the major faults around Xiluodu dam,China
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作者 Li Liao Ping′en Li +1 位作者 Jiansi Yang Jianzhou Feng 《Earthquake Science》 2022年第5期398-409,共12页
Simulations of the spontaneous rupture of potential earthquakes in the vicinity of reservoir dams can provide accurate parameters for seismic resilience assessment,which is essential for improving the seismic performa... Simulations of the spontaneous rupture of potential earthquakes in the vicinity of reservoir dams can provide accurate parameters for seismic resilience assessment,which is essential for improving the seismic performance of reservoir dams.In simulations of potential spontaneous ruptures,fault geometry,regional stress fields,constitutive parameters of the fault friction law,and many other factors control the slip rate,morphology,and dislocation of the rupture,thereby affecting the simulated ground motion parameters.The focus of this study was to elucidate the effects of the background stress field on the nucleation and propagation of spontaneous ruptures based on the factors influencing potential M>7 earthquake events on the Leibo Middle Fault(LBMF)and the Mabian-Yanjing Fault(MB-YJF)in the Xiluodu dam(XLD)region.Our simulation results show that the magnitude of the regional background stress field plays a decisive role in whether a destructive earthquake exceeding the critical magnitude will occur.We found that the direction and magnitude of the regional stress significantly affect the range of rupture propagation on the fault plane,and fault geometry affects the spatial distribution of the rupture range.Under the same regional stress field magnitude and orientation,a more destructive,high-magnitude earthquake is more likely to occur on the LBMF than on the MB-YJF. 展开更多
关键词 Xiluodu dam regional background stress field spontaneous rupture simulation
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Iterative analysis of landscape design pattems from the artistic attributes and regional background angles
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作者 Tao Zhang 《International Journal of Technology Management》 2017年第4期77-79,共3页
Urban green space system is an important part of the overall urban planning, which is an important part of improving the quality of urban ecological environment, improving the living standards of people, and creating ... Urban green space system is an important part of the overall urban planning, which is an important part of improving the quality of urban ecological environment, improving the living standards of people, and creating an ecological livable city. Landscape design of urban green space is one of the specific performance of green space system. Along with the people to the living environment of increasing demand, the traditional green landscape forms of cultural meaning and basic entertainment and leisure function, can not fully meet the needs of modem people, people hope the environment landscape can convey with contemporary cultural atmosphere of the living environment context, hope the new form of the landscape can pay attention to the time the theme can re-examine the harmonious coexistence of man and nature, the way to create the green landscape has become an important carrier of cultural heritage and the progress of civilization to a certain extent. Based on the analysis of the development trend of urban green space landscape design, this paper sums up some characteristics of the design pattern. 展开更多
关键词 Artistic attribute regional background landscape design
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze River and neighbouring areas
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Contrast and Fusion: The Role of Regional Culture in Shaping Jiangsu Paper-Cut Art
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作者 Yan Gu 《Journal of Contemporary Educational Research》 2023年第6期64-77,共14页
The Chinese paper-cut art,first recorded in the Wei,Jin,and Southern and Northern Dynasties(220 AD-589 AD),has witnessed the changes of times,yet it still retains its artistic vitality.Chinese papercuts can be divided... The Chinese paper-cut art,first recorded in the Wei,Jin,and Southern and Northern Dynasties(220 AD-589 AD),has witnessed the changes of times,yet it still retains its artistic vitality.Chinese papercuts can be divided into two schools:the northern and the southern.Jiangsu,located in the region of the Yellow River and Huai River,is the geographical dividing line between those two schools.Therefore,in Jiangsu Province,not only the rough northern art form(such as in Xuzhou papercut)but also the graceful southern art form(such as in Jintan papercut)is evident.In addition,the unique combined paper-cut style(such as in Yangzhou and Nanjing papercuts)can be appreciated here.Although several scholars have analyzed the artistic characteristics of Jiangsu papercut based on cultural background,very few have discussed the differences between the northern and the southern in terms of content,connotation,and style.Through literature review and collected works made by local craftsmen and inheritors of this tradition,this article aims to show readers the contrast and integration of papercuts in these four places under the influence of different cultural and economic backgrounds in order to better understand the role of regional factors in shaping the art form of papercuts in Jiangsu Province.Nowadays,with the change in people’s lifestyles,the living space of traditional papercuts has shrunk drastically,and its practicability in the past has faded.Instead,people are searching for and creating cultural and artistic value in museums,tourist attractions,and commodity transactions.Among them,some works have deviated from the cultural background of traditional paper-cut art.Therefore,this paper provides a basis for the current development of this art form in Jiangsu. 展开更多
关键词 Chinese papercuts Jiangsu papercut regional cultural background Comparison INTEGRATION
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A Deep Learning Framework for Mass-Forming Chronic Pancreatitis and Pancreatic Ductal Adenocarcinoma Classification Based on Magnetic Resonance Imaging
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作者 Luda Chen Kuangzhu Bao +2 位作者 Ying Chen Jingang Hao Jianfeng He 《Computers, Materials & Continua》 SCIE EI 2024年第4期409-427,共19页
Pancreatic diseases, including mass-forming chronic pancreatitis (MFCP) and pancreatic ductal adenocarcinoma(PDAC), present with similar imaging features, leading to diagnostic complexities. Deep Learning (DL) methods... Pancreatic diseases, including mass-forming chronic pancreatitis (MFCP) and pancreatic ductal adenocarcinoma(PDAC), present with similar imaging features, leading to diagnostic complexities. Deep Learning (DL) methodshave been shown to perform well on diagnostic tasks. Existing DL pancreatic lesion diagnosis studies basedon Magnetic Resonance Imaging (MRI) utilize the prior information to guide models to focus on the lesionregion. However, over-reliance on prior information may ignore the background information that is helpful fordiagnosis. This study verifies the diagnostic significance of the background information using a clinical dataset.Consequently, the Prior Difference Guidance Network (PDGNet) is proposed, merging decoupled lesion andbackground information via the Prior Normalization Fusion (PNF) strategy and the Feature Difference Guidance(FDG) module, to direct the model to concentrate on beneficial regions for diagnosis. Extensive experiments inthe clinical dataset demonstrate that the proposed method achieves promising diagnosis performance: PDGNetsbased on conventional networks record an ACC (Accuracy) and AUC (Area Under the Curve) of 87.50% and89.98%, marking improvements of 8.19% and 7.64% over the prior-free benchmark. Compared to lesion-focusedbenchmarks, the uplift is 6.14% and 6.02%. PDGNets based on advanced networks reach an ACC and AUC of89.77% and 92.80%. The study underscores the potential of harnessing background information in medical imagediagnosis, suggesting a more holistic view for future research. 展开更多
关键词 Pancreatic cancer PANCREATITIS background region prior normalization fusion feature difference guidance
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The Method of Spatially Smoothed Seismicity Parameters in Consideration of Seismotectonic Background and Its Application to Seismic Hazard Estimation
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作者 Zhang Lifang Lv Yuejun +2 位作者 Peng Yanju Ma Xiaoling Cui Manfeng 《Earthquake Research in China》 2013年第1期121-132,共12页
In this study, the North China seismic region was selected as the study area, and evaluation of seismic hazard using the spatial smoothing seismicity model was performed. Firstly, the study area is divided into grids,... In this study, the North China seismic region was selected as the study area, and evaluation of seismic hazard using the spatial smoothing seismicity model was performed. Firstly, the study area is divided into grids, and some parameters (e. g. b-value, Mo, Me, azimuth and M-L relationship ) for each seismotectonic model were assigned. Secondly, using elliptical smoothing based on a seismotectonic background model, the statistical earthquake incidence rate in each grid is successively calculated. Lastly, the relevant ground motion attenuation relationship is chosen to assess seismic hazard of general sites. The maps for the distribution of horizontal peak ground acceleration with 10% probability of exceedance in 50 years were obtained by using the seismic hazard analysis method based on grid source. This seismicity model simplifies the methodology of probabilistic seismic hazard analysis, especially appropriate for those places where seismic tectonics is not yet clearly known. This method can provide valuable references for seismic zonation and seismic safety assessment for significant engineering projects. 展开更多
关键词 North China seismic region Seismotectonic background region Seismichazard estimation Spatial smoothing approach
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Background concentrations of reactive gases and the impacts of long-range transport at the Jinsha regional atmospheric background station 被引量:8
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作者 LIN WeiLi XU XiaoBin +2 位作者 SUN JunYing LIUXiWen WANG Ying 《Science China Earth Sciences》 SCIE EI CAS 2011年第10期1604-1613,共10页
Lorentz curve fittings are applied to frequency distributions of the concentrations of O3, CO, NOx and SO2 recorded at the Jinsha regional atmospheric background station (JSH) from June 2006 to July 2007, and the pe... Lorentz curve fittings are applied to frequency distributions of the concentrations of O3, CO, NOx and SO2 recorded at the Jinsha regional atmospheric background station (JSH) from June 2006 to July 2007, and the peak concentrations of these species for the different seasons are obtained. The peak concentrations are considered to be representative of different background levels for certain processes. The peak concentrations are compared with the corresponding mean (median) concentrations, and the suitability and limitations of the mean (median) values as the background levels are discussed. The mean (median) values might represent the background concentrations in the region under some circumstances, but in other cases these values often underestimate or overestimate the true background concentrations owing to the transport of pollutants and other factors. The effects of air masses transported from different regions on the pollutant background concentrations are obtained by analyzing the 72-hour backward trajectories of air masses 100m above the ground at JSH, These trajectories are estimated using the HYSPLIT model and then clustered for the measurement period. The spatial distribution and seasonal variations of trajectories and the corresponding mean concentrations of O3, SO〉 NOx and CO for different clusters are analyzed. After filtering the seasonal changes in pollutant concentrations, the relative influences of air masses from different regions are obtained. The results show that JSH can be used to obtain the atmospheric background information of different air masses originating from or passing over the Yangtze River Delta, Central South China and the Jianghan Plain. Air masses from Central China, South China, and the western Yangtze River Delta contribute significantly to O3 at JSH. Air masses from the north and northeast of JSH (i.e., the Jianghan Plain, Huang-Huai Plain and North China Plain) and the south (Central South China) contribute significantly to SO2, CO and NOx concentrations. Air masses originating from the ocean often bring clean air. Air masses originating from high altitudes over northwestern regions often have lower CO and NO3 concentrations, lower relative humidity, and higher concentrations of O3 and SO2. 展开更多
关键词 Jinsha regional atmosphere background station background signal Lorentz curve fitting air transport O3 CO NOx SO2
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Emission inventory evaluation using observations of regional atmospheric background stations of China 被引量:7
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作者 Xingqin An Zhaobin Sun +2 位作者 Weili Lin Min Jin Nan Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第3期537-546,共10页
Any accurate simulation of regional air quality by numerical models entails accurate and up-to-date emissions data for that region.The INTEX-B2006 (I06),one of the newest emission inventories recently popularly used... Any accurate simulation of regional air quality by numerical models entails accurate and up-to-date emissions data for that region.The INTEX-B2006 (I06),one of the newest emission inventories recently popularly used in China and East Asia,has been assessed using the Community Multiscale Air Quality model and observations from regional atmospheric background stations of China.Comparisons of the model results with the observations for the species SO2,NO 2,O 3 and CO from the three regional atmospheric background stations of Shangdianzi,Longfengshan and Linan show that the model can basically capture the temporal characteristics of observations such as the monthly,seasonal and diurnal variance trends.Compared to the other three species,the simulated CO values were grossly underestimated by about two-third or one-half of the observed values,related to the uncertainty in CO emissions.Compared to the other two stations,Shangdianzi had poorer simulations,especially for SO2 and CO,which partly resulted from the site location close to local emission sources from the Beijing area;and the regional inventory used was not capable of capturing the influencing factors of strong regional sources on stations.Generally,the fact that summer gave poor simulation,especially for SO2 and O 3,might partly relate to poor simulations of meteorological fields such as temperature and wind. 展开更多
关键词 evaluation CMAQ model INTEX-B2006 inventory regional atmospheric background stations
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Characteristic of Rare EarthDistribution in Biologic Chains of RE-Rich Back-ground Regions
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作者 Zhang Hui Feng Jia ZhuWeifang (Institute of Geochemistry,Chinese Academy of Sciences,Cuiyang 550002, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第4期307-307,共1页
REE contents of water and vegetables, from two typical RE-rich background regionsand normal region in Gainan,Jiangxi Province, China, indicatethat REE contents are markedlydifferent in water and vegetables.There are a... REE contents of water and vegetables, from two typical RE-rich background regionsand normal region in Gainan,Jiangxi Province, China, indicatethat REE contents are markedlydifferent in water and vegetables.There are average 0.03 mg·L-1and 0. 11 mg·L-1 REE in water ofA and B regions. As REE contentsof vegetables for A region are different from B region, it suggeststhat there are a lot of factors controlling REE distribution betweenvegetables. Comparing with thenormal region, soluble RE contentsin water of the RE-rich backgroundregions are factors of 68 and 18than that of the normal region.REE contents of the most plantsand crops in A and B regions arehigher than that in the normal region. It is clear that REE are theindispensable elements of plantsduring their growing period. Asthere are unusually higher REEcontents of some plants in A and Bthan in the normal regions, it isconsidered to result from absorbingREE passively during the period ofplants and crops growing up. 展开更多
关键词 Rare earths RE-rich background regions Biologic chains
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Key features of new particle formation events at background sites in China and their influence on cloud condensation nuclei 被引量:5
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作者 Xiaojing SHEN Junying SUN +3 位作者 Xiaoye ZHANG Yangmei ZHANG Lu ZHANG Ruxia FAN 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2016年第5期107-117,共11页
Long-term continuous measurements of particle number size distributions with mobility diameter sizes ranging from 3 to 800 nm were pertbrmed to study new particle formation (NPF) events at Shangdianzi (SDZ), Mt. T... Long-term continuous measurements of particle number size distributions with mobility diameter sizes ranging from 3 to 800 nm were pertbrmed to study new particle formation (NPF) events at Shangdianzi (SDZ), Mt. Tai (TS), and Lin'an (LAN) stations representing the background atmospheric conditions in the North China Plain (NCP) Central East China (CEC) and Yangtze River Delta (YRD) regions, respectively. The mean formation rate of 3-nm particles was 6.3, 3.7, and 5.8 cm -3 .s-1, and the mean particle growth rate was 3.6, 6.0, and 6.2 nm. h at SDZ, TS, and LAN, respectively. The NPF, event characteristics at the three sites indicate that there may be a stronger source of low volatile vapors and higher condensational sink of pre-existing particles in the YRD region. The formation rate of NPF events at these sites, as well as the condensation sink, is approximately 10 times higher than some results reported at rural/urban sites in western countries. However, the growth rates appear to be 1 2 times higher. Approximately 12%-17% of all NPF events with nucleated particles grow to a climate- relevant size (〉50 nm). These kinds of NPF events were normally observed with higher growth rate than the other NPF cases. Generally, the cloud condensation nuclei (CCN) number concentration can be enhanced by approximately a factor of 2 6 on these event days. The mean value of the enhancement factor is lowest at LAN (2-3) and highest at SDZ (-4). NPF events have also been found to have greater impact on CCN production in China at the regional scale than in the other background sites worldwide. 展开更多
关键词 New particle formation regional background Cloud condensation nuclei Growth rate Formation rate
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Composition and mixing state of water soluble inorganic ions during hazy days in a background region of North China 被引量:3
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作者 LU YaLing CHI JianWei +4 位作者 YAO Lan YANG LingXiao LI WeiJun WANG ZiFa WANG WenXing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第11期2026-2033,共8页
Knowledge of haze particles in background areas of North China is limited, although they have been studied well in urban settings. Atmospheric aerosol particles were collected at a background site in the North China P... Knowledge of haze particles in background areas of North China is limited, although they have been studied well in urban settings. Atmospheric aerosol particles were collected at a background site in the North China Plain during 16–31 January, 2011. Water soluble inorganic ions of PM2.5 and physicochemical characteristics of individual particles on hazy and clean days were measured by Ion Chromatography(IC) and Transmission Electron Microscopy(TEM), respectively. Average PM2.5 mass concentration was 50.4±29.9 μg m?3 with 62.5±26.8 μg m?3 on hazy days and 19.9±11.5 μg m?3 on clean days. SO42?, NO3?, and NH4+ with a combined mass concentration of 19.0±11.5 μg m?3 accounted for 69.8%–89.4% of the total water soluble inorganic ions. Size distributions of SO42? and NH4+ showed one unimodal peak at 0.56–1.8 μm on hazy days, whereas NO3? appeared as bimodal peaks at 0.56–1.8 and 5.6–10 μm, respectively. Individual particle analyses showed that the dominant aerosols were a mixture of sulfate, nitrate, and carbonaceous species, which together determine their mixing states. 48-h air mass back trajectories on hazy days suggested that air masses crossed the polluted continental areas(such as Jing-jin-ji region and Shandong province) and entrained ground air pollutants 11–19 hours before reaching the background area. During long-range transport particles undergo ageing and tend to be internally mixed mainly due to condensation in the background atmosphere. Our results suggest that hygroscopic and optical properties of these aerosol particles in the background area differ substantially from those in urban areas. 展开更多
关键词 water soluble inorganic ions individual particles secondary particles mixing state background region haze episode
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In situ measurement of atmospheric carbon dioxide at Yanbian,China:Estimating its northeast Asian emission regions 被引量:1
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作者 JIN FenJi FANG YingYu +5 位作者 CHEN Tie LI DongHao KIM Jooil PARK Mi-Kyung PARK Sunyoung KIM Kyung-Ryul 《Science China Earth Sciences》 SCIE EI CAS 2012年第10期1742-1748,共7页
High-precision(±0.1 ppm) and high-frequency(hourly averaged) in situ measurements of atmospheric carbon dioxide(CO2) were made for the first time from August 2005 to July 2007 at Yanbian,China using a non-dispers... High-precision(±0.1 ppm) and high-frequency(hourly averaged) in situ measurements of atmospheric carbon dioxide(CO2) were made for the first time from August 2005 to July 2007 at Yanbian,China using a non-dispersive Infrared(NDIR) analyzer with National Oceanic and Atmospheric Administration/Earth System Research Laboratory(NOAA/ESRL) standards.The results of these measurements are presented in this paper and are used to investigate the regional representativeness of regional background data at Yanbian and determine the CO2 emission source regions in Northeast Asia.The phase of the monthly variations at Yanbian reflects the special regional characteristics,which were overall in excellent agreement with other observatories in the middle-to-high latitudes in the Northern Hemisphere.Applying a hybrid receptor model to the regional emission source events in cold period(November-April),we estimated the distribution of the major CO2 emissions in the northeast Asia.The results indicated that the strongest potential emission areas contributing to Yanbian are the Beijing & Tianjin metropolitan areas,southwestern part of Shandong Province including Jinan,and Vladivostok.The results of this study reveal the usefulness of in situ CO2 measurements at Yanbian in establishing the scientific foundation for monitoring the large CO2 emission areas in northern China and Russia.Continued monitoring of CO2 at Yanbian within a regional network should provide significant contributions to both understanding the global/regional carbon cycle and constraining "top-down" emissions in Northeast Asia. 展开更多
关键词 carbon dioxide emission regions in situ monitoring Northeast Asia regional background Yanbian
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