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Variation in reproductive life-history traits of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China
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作者 Xingmin Chen Qin Zhang +3 位作者 Sisi Lan Qin Huang Shuihua Chen Yanping Wang 《Avian Research》 SCIE CSCD 2023年第2期174-181,共8页
Urbanization brings new selection pressures to wildlife living in cities,and changes in the life-history traits of urban species can reflect their responses to such pressures.To date,most of the studies investigating ... Urbanization brings new selection pressures to wildlife living in cities,and changes in the life-history traits of urban species can reflect their responses to such pressures.To date,most of the studies investigating the impacts of urbanization on avian life-history traits are conducted in Europe and North America,while such studies are often lacking in quickly developing countries in Asia(e.g.,China).In this study,we examined the variations in reproductive life-history traits of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China.We detected 234 natural nests of Chinese Bulbuls and continuously monitored them in two continuous breeding seasons from 2012 to 2013.We collected data on seven life-history traits(laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate).We used infrared cameras to record the number of feedings per hour as the measure of food resources for the nestlings.We measured nest predation pressure by monitoring 148 natural breeding nests during breeding seasons and 54 artificial nests immediately after breeding seasons.We then calculated the urbanization synthetic index(USI)as a measure of the level of urbanization and examined its relationship with the seven life-history traits.We found that Chinese Bulbuls laid eggs significantly earlier with increasing USI.However,the other six life-history traits did not vary significantly with the USI.Moreover,the feeding frequency of chicks increased significantly with the USI,but the nest predation pressure of Chinese Bulbuls decreased significantly with the USI.Increased food resources and reduced nest predation pressure in cities may lead to earlier laying date of Chinese Bulbuls.Further study should test whether the earlier laying date of Chinese Bulbuls is the result of phenotypic plasticity or genetic change. 展开更多
关键词 Feeding frequency Laying date Life-history trait Nest predation URBANIZATION Urbanization synthetic index(USI)
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Assessment and mapping of environmental quality in agricultural soils of Zhejiang Province, China 被引量:67
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作者 CHENG Jie-liang SHI Zhou ZHU You-wei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期50-54,共5页
Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samp... Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal (Cd, Cr, Pb, Hg, Cu, Zn, Ni and As) concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow's synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China (GB15618- 1995). Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted (IDW) interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow's pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis (PCA) and the principal components (PCs) were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government. 展开更多
关键词 agricultural soil heavy metals soil environmental quality Nemerow's synthetical pollution index multivariate analysis
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A New Index Developed for Fast Diagnosis of Meteorological Roles in Ground-Level Ozone Variations 被引量:3
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作者 Weihua CHEN Weiwen WANG +11 位作者 Shiguo JIA Jingying MAO Fenghua YAN Lianming ZHENG Yongkang WU Xingteng ZHANG Yutong DONG Lingbin KONG Buqing ZHONG Ming CHANG Min SHAO Xuemei WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第3期403-414,558-563,共18页
China experienced worsening ground-level ozone(O_(2)) pollution from 2013 to 2019. In this study, meteorological parameters, including surface temperature(T_(2)), solar radiation(SW), and wind speed(WS), were classifi... China experienced worsening ground-level ozone(O_(2)) pollution from 2013 to 2019. In this study, meteorological parameters, including surface temperature(T_(2)), solar radiation(SW), and wind speed(WS), were classified into two aspects,(1) Photochemical Reaction Condition(PRC = T_(2)× SW) and(2) Physical Dispersion Capacity(PDC = WS). In this way, a Meteorology Synthetic Index(MSI = PRC/PDC) was developed for the quantification of meteorology-induced ground-level O_(2)pollution. The positive linear relationship between the 90 th percentile of MDA8(maximum daily 8-h average) O_(2)concentration and MSI determined that the contribution of meteorological changes to ground-level O-3 varied on a latitudinal gradient, decreasing from ~40% in southern China to 10%–20% in northern China. Favorable photochemical reaction conditions were more important for ground-level O_(2)pollution. This study proposes a universally applicable index for fast diagnosis of meteorological roles in ground-level O_(2)variability, which enables the assessment of the observed effects of precursor emissions reductions that can be used for designing future control policies. 展开更多
关键词 ground-level ozone meteorology synthetic index photochemical reaction condition physical dispersion capacity
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The Response of Climatic Jump in Summer in North China to Global Warming 被引量:1
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作者 黄嘉佑 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期184-192,共9页
To reveal climatic variation over North China, the climatic jumps in summer in Beijing are analyzed using the data of precipitation of summer (June, July, August) during the period of 1841-1993, in which those missed ... To reveal climatic variation over North China, the climatic jumps in summer in Beijing are analyzed using the data of precipitation of summer (June, July, August) during the period of 1841-1993, in which those missed before 1950 were reconstructed by the stepwise regression method with minimum forecast error. The climatic jumps at different scales are analyzed using different diagnostic methods with different decade (10-100 years) windows. Some new methods and ideas are proposed. The variance difference, the linear tendency difference, and the difference of power spectral distribution between the samples before and after the period at the moving point in the center of the series are compared with other methods (for example, Mann—Kendall test, t— test, and accumulative anomaly etc.). Considering the differences among the statistics above, a synthetic jump index is also proposed in order to get the definite jump points in the moving series. The results show that the climatic jumps in the area occurred in the 1890s, the 1910s and the 1920s, and mostly in the 1920s, which suggests that the local climatic jumps in North China have a simultaneous response to the global warming in the hundred-year scales. Key words Climatic jump - New diagnostic statistics - Synthetic jump index - Response to global warming This Study was supported by the “ National Key Programme for Developing Basic Sciences” G1998040901-1. 展开更多
关键词 Climatic jump New diagnostic statistics Synthetic jump index Response to global warming
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Integral Optimization of Systematic Parameters of Flip-Flow Screens 被引量:1
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作者 翟宏新 《Journal of China University of Mining and Technology》 2004年第1期77-81,共5页
The synthetic index K s for evaluating flip-flow screens is proposed and systematically optimized in view of the whole system. A series of optimized values of relevant parameters are found and then compared with those... The synthetic index K s for evaluating flip-flow screens is proposed and systematically optimized in view of the whole system. A series of optimized values of relevant parameters are found and then compared with those of the current industrial specifications. The results show that the optimized value K s approaches the one of those famous flip-flow screens in the world. Some new findings on geometric and kinematics parameters are useful for improving the flip-flow screens with a low K s value, which is helpful in developing clean coal technology. 展开更多
关键词 synthetic index Ks flip-flow screen clean coal optimization fines sieving
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Spatial identification of poverty in mountainous cities based on the mountain poverty spatial index:A case study of Ganzhou city in 2018 in China
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作者 WANG Jin-liang CUI Zhi-chao ZHOU Bing-juan 《Journal of Mountain Science》 SCIE CSCD 2022年第11期3213-3226,共14页
Poverty is a severe barrier to sustainable human development and a pressing worldwide issue.Understanding how to accurately assess the spatial distribution of poverty in mountain areas has become crucial for ensuring ... Poverty is a severe barrier to sustainable human development and a pressing worldwide issue.Understanding how to accurately assess the spatial distribution of poverty in mountain areas has become crucial for ensuring that governments at all levels take suitable poverty reduction strategies.In this study,the mountain poverty spatial index(MPSI)was created by combining the digital elevation model(DEM),Luojia-1 night-time light imagery,point of interest(POI)data,and vegetation index products.The MPSI was then used to identify the spatial characteristics of poverty at different scales in the hilly area of Ganzhou city,Jiangxi Province,China.Socioeconomic statistics and Google satellite images were used to verify the reliability of MPSI by constructing a multidimensional poverty index(MPI)at the county scale.The results showed that MPSI and MPI have a positive correlation with a correlation coefficient of 0.8934(P<0.001),which indicates that MPSI could be used to identify the spatial distribution of poverty well.Specifically,the smallest distribution of both MPSI and MPI was in Zhanggong District(1.4555 and 0.1894),which indicates that most of the affluent counties were concentrated in the central region of Ganzhou,and the poor areas were scattered in the surrounding areas of Ganzhou.In addition,MPSI accurately identified poverty in mountainous areas with complex terrain in small administrative units,which can provide a more accurate way to monitor the poverty situation in the mountainous areas of China.This study will be useful for providing scientific references for the Chinese government to implement targeted strategies for eradicating poverty with differentiated policies. 展开更多
关键词 Mountain poverty Night-time light Remote sensing imagery Vegetation index Point of interest Synthetic human settlement index
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Integrated Evaluation and Its Application on Decision-Making of Comprehensive Transportation Projects
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作者 LIXue-mei ZHANGTao 《Journal of China University of Mining and Technology》 EI 2005年第1期72-76,共5页
The comprehensive transportation project involves with many different transportation methods, such as railway, highway, waterway, airline, and pipeline, which have their special characteristics. To evaluate the transp... The comprehensive transportation project involves with many different transportation methods, such as railway, highway, waterway, airline, and pipeline, which have their special characteristics. To evaluate the transporta- tion project with different transportation methods under the same system, the integrated evaluation method should be built up on the basis of a common index system. This paper suggests a feasible integrated evaluation method including index system establishing, indices transacting, the index weight distributing, and weighted value integrating. 展开更多
关键词 comprehensive transportation synthetic index system integrated evaluation method
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Dimensional analysis of the impact toughness test for synthetic diamond grits
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作者 杨慧 麦绿波 +4 位作者 卢灿华 仝毅 王志涛 张凤岭 黄风雷 《Journal of Beijing Institute of Technology》 EI CAS 2016年第1期1-6,共6页
The method,in which a few carats of diamond grits are placed inside a capsule together with a steel ball,shaken for a number of times,and the unbroken ratio of the grits is then used to evaluate the quality of the dia... The method,in which a few carats of diamond grits are placed inside a capsule together with a steel ball,shaken for a number of times,and the unbroken ratio of the grits is then used to evaluate the quality of the diamond,has been well established for many years.However,the unbroken percentage,in an equivalent view,represents the impact toughness of the grits and cannot reflect the value of the crushing energy.Most of the previous empirical formulas obtained from experiments by scholars cannot be applied to practical tests.In this paper,a dimensional analysis was applied to investigate the impact toughness experiment,and the dimensionless relationship has been built among those variables such as the toughness index,the impact time,the impact frequency and the crushing energy per unit area.According to the results of a large number of experiments with synthetic diamond grits of mesh size 45/50,the percentage of the broken grits H is proportional to the impact time T^(1.14) when the impact frequency is 2400 r/min,and the impact frequency f^(2.576) when the number of impacts is 2000. 展开更多
关键词 synthetic diamond toughness index dimensional analysis impact toughness test
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Study on the Remote Sensing Assessment of Seismic Intensity of the Yushu Earthquake Based on the Synthetic Seismic Damage Index
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作者 Wang Xiaoqing Dou Aixia +3 位作者 Sun Guoqing Ding Xiang Wang Long Yuan Xiaoxiang 《Earthquake Research in China》 2014年第1期22-33,共12页
This paper provides an overview of the ideas and methods of the assessment of seismic intensity based on remote sensing and describes the models used to assess the remote sensing based synthetic seismic damage index a... This paper provides an overview of the ideas and methods of the assessment of seismic intensity based on remote sensing and describes the models used to assess the remote sensing based synthetic seismic damage index and seismic intensity. With the data of damage information extracted from the high-resolution aerial images in the earthquake-stricken areas( Jiegu town,Yushu city,Qinghai) of the 2010 MS7. 1 Yushu earthquake,and the data obtained through post-earthquake field investigation,the seismic damage degree and seismic intensity have been estimated. The analysis of the results shows that the seismic intensity in Yushu city is estimated as IX through the RS assessment method,which is consistent with the result estimated according to the ground surveys. The results are discussed in the last part of the paper and indicate that the RS techniques are expected to be one of the main methods used to estimate the seismic intensity values in the emergency stage. 展开更多
关键词 Seismic damage of building Synthetic seismic damage index Seismicintensity Remote sensing assessment
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A local spectrum enhancement-based method and its application in incipient fault diagnosis of rotating machinery 被引量:1
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作者 Jiancong Shi Baoming Xu +1 位作者 Xinglong Wang Jun Zhang 《International Journal of Mechanical System Dynamics》 2023年第2期162-172,共11页
Incipient faults of gears and rolling bearings in rotating machineries are very difficult to identify using traditional envelope analysis methods.To address this challenge,this paper proposes an effective local spectr... Incipient faults of gears and rolling bearings in rotating machineries are very difficult to identify using traditional envelope analysis methods.To address this challenge,this paper proposes an effective local spectrum enhancement‐based diagnostic method that can identify weak fault frequencies in the original complicated raw signals.For this purpose,a traversal frequency band segmentation technique is first proposed for dividing the raw signal into a series of subfrequency bands.Then,the proposed synthetic quantitative index is constructed for selecting the most informative local frequency band(ILFB)containing fault features from the divided subfrequency bands.Furthermore,an improved grasshopper optimization algorithmbased stochastic resonance(SR)system is developed for enhancing weak fault features contained in the selected most ILFB with less computation cost.Finally,the enhanced weak fault frequencies are extracted from the output of the SR system using a common spectrum analysis.Two experiments on a laboratory planetary gearbox and an open bearing data set are used to verify the effectuality of the proposed method.The diagnostic results demonstrate that the proposed method can identify incipient faults of gears and bearings in an effective and accurate manner.Furthermore,the advantages of the proposed method are highlighted by comparison with other methods. 展开更多
关键词 fault diagnosis frequency band segmentation adaptive stochastic resonance improved grasshopper optimization algorithm synthetic quantitative index
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Diagenesis and diagenetic stages prediction of Ed2 reservoir in the west of Bozhong sag 被引量:1
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作者 Wendao Qian Taiju Yin +2 位作者 Changmin Zhang Guowei Hou Miao He 《Petroleum》 CSCD 2020年第1期23-30,共8页
Diagenesis of clastic rock and hydrocarbon generating capacity are closely related with diagenetic stages.Based on diagenetic evolution,reservoir diagenetic stages prediction method is proposed through making a contra... Diagenesis of clastic rock and hydrocarbon generating capacity are closely related with diagenetic stages.Based on diagenetic evolution,reservoir diagenetic stages prediction method is proposed through making a contrastive study of simulation results and test results using core measurement data.The essence of this method is illustrated and its effectiveness is demonstrated using Ed2 clastic sandstones in the west of Bozhong sag,Bohai Bay Basin,China.Measurement of paleo temperature(T),vitrinite reflectivity(Ro%)and the proportion of smectite in illite/smectite interstratified minerals(I/S-S%)indicate that there are there types of diagenetic stages in the study area,including early diagenetic stage B,middle diagenetic stage A1 and middle diagenetic stage A2.When only considering T index for diagenetic stages prediction,the simulation results are more conservative than measured data with some situations,and the simulation result using Ro%for diagenetic prediction is less than measured data in some wells.When I/S-S%is used,the two situations above both exist.Because depth,temperature,time duration,pressure and some chemical variables can change synchronously or asynchronously,it is difficult to attribute with certainty the parameters that affect the apparent diagenetic stages evolution series.Diagenetic stage variations can be significantly different in different parts of one sedimentary basin.A synthetic indexes method considering T,Ro%,I/S-S%to predict its distribution,and the simulation result has proved that the reliability of the model has greatly improved. 展开更多
关键词 Diagenetic stages Clastic sandstones Bozhong sag Diagenetic simulation OVERPRESSURE Synthetic indexes
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