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Establishing environmental background values of selected trace elements and environmental quality assessment of fi negrained sediments in the Jiaozhou Bay catchment,China
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作者 Fangjian XU Xu TIAN +2 位作者 Xianchao WANG Xiaoming WAN Bo CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1444-1453,共10页
With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained... With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained sediment samples from the Jiaozhou Bay catchment were selected to evaluate their 2015 environmental background values and the environmental quality.Using statistical analysis,the environmental background values(ranges)of Sc,Co,Ni,Cu,Pb,Zn,Cd,and Cr were calculated,being 13.1(10.8-15.4),12.4(8.6-16.2),32.0(22.9-41.2),29.6(13.5-64.9),24.1(13.0-44.6),77.6(38.5-156.5),0.07(0.02-0.20),and 82.5(66.5-104.0)mg/kg,respectively.The enrichment factor,contamination factor,and pollution load index were used to evaluate the pollution status of the Jiaozhou Bay catchment.The environmental background values of most elements are higher than those of the upper continental crust and lower than those of global shale.At present,the pollution in the eastern Jiaozhou Bay is much higher than that in the western part.The results shall be helpful for future management for trace element pollution monitoring in the Jiaozhou Bay catchment. 展开更多
关键词 SEDIMENTS environmental background values environmental assessment CONTAMINATION Jiaozhou Bay
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Optimization approach of background value and initial item for improving prediction precision of GM(1,1) model 被引量:32
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作者 Yuhong Wang Qin Liu +2 位作者 Jianrong Tang Wenbin Cao Xiaozhong Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期77-82,共6页
A combination method of optimization of the back-ground value and optimization of the initial item is proposed. The sequences of the unbiased exponential distribution are simulated and predicted through the optimizati... A combination method of optimization of the back-ground value and optimization of the initial item is proposed. The sequences of the unbiased exponential distribution are simulated and predicted through the optimization of the background value in grey differential equations. The principle of the new information priority in the grey system theory and the rationality of the initial item in the original GM(1,1) model are ful y expressed through the improvement of the initial item in the proposed time response function. A numerical example is employed to il ustrate that the proposed method is able to simulate and predict sequences of raw data with the unbiased exponential distribution and has better simulation performance and prediction precision than the original GM(1,1) model relatively. 展开更多
关键词 background value initial item grey system theory grey prediction.
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A study on the environmental background values in the Mt. Namjagbarwa region, Tibet 被引量:1
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作者 Huang Yanchu, Liu Quangyou, Ma Ciguang and Shan Xiaoquan Research Center for Eco-Environmetal sciences,Academia Sinica,P.O.Box 934,Beijing 100083, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第1期39-45,共7页
A study on the elemental composition of aerosol, water and soil in the Mt. Namjagbarwa region, Tibet, was carried out in the period of 1982 to 1984. Samples of aerosol particles were collected by cascade impactor and ... A study on the elemental composition of aerosol, water and soil in the Mt. Namjagbarwa region, Tibet, was carried out in the period of 1982 to 1984. Samples of aerosol particles were collected by cascade impactor and analyzed for 10 elements by PIXE. Samples of ice, snow and water were collected and analyzed for trace metals, major cations and anions. The pH values of water were at quasi-neutrality or neutrality, and the hardness of water was low. Contents and physico-chemical composition of 20 elements in the major types of soil were determined by physico-chemical methods. Levels of elements in soil varied with soil type and their parent materials. Contents of some elements were higher in the substratum soil derived from in situ than in the surface soil. The region was in a remote area with negligible pollution and could be considered as a good location for measuring the baskground value of environmental sample. 展开更多
关键词 AEROSOL water SOIL background value.
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Soil Geochemical Background Value and Environmental Quality Assessment in Jinan City
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作者 Hongjin WANG Chao YU +1 位作者 Wenkai REN Yan GUO 《Agricultural Biotechnology》 CAS 2022年第5期72-75,79,共5页
[Objectives]This study was conducted to accurately assess soil and environmental quality in Jinan City. [Methods] Based on the multipurpose regional geochemical survey data of 1∶250 000 in Shandong Province, the diff... [Objectives]This study was conducted to accurately assess soil and environmental quality in Jinan City. [Methods] Based on the multipurpose regional geochemical survey data of 1∶250 000 in Shandong Province, the differences between the soil geochemical background values of 54 indexes in Jinan City and the soil in the whole province and the comprehensive geochemical class of soil quality were studied. [Results] The contents of C and Cao in Jinan soil was significantly higher than the background values of Shandong Province. The Cd, Cr, Cu, F, Ni, Sn, MgO, Cao and Na_(2)O contents and pH value were higher than the abundance of the A soil layer in China, but the nutrient index contents of Se, I and OrgC were lower than the national background values. The surface soil quality in the study area was generally good, with the sum of superior, good and medium accounting for 99.76% of the total area of the study area. The distribution area of poor soil was the least, accounting for only 0.24%, and it was scattered near industrial and mining enterprises in the urban area of Jinan City, Laiwu District, Gangcheng District and Zhangqiu District, which was closely related to human activities. [Conclusions] This study has practical guiding significance for improving land use efficiency. 展开更多
关键词 Surface soil background value GEOCHEMISTRY Land quality Assessment Jinan city
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling OPTIMUM background value two times fitting
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Improvement and application of GM(1,1) model based on multivariable dynamic optimization 被引量:12
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作者 WANG Yuhong LU Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期593-601,共9页
For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the backgrou... For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the background value as a variable related to k.At the same time,the initial value is set as a variable,and the corresponding optimal parameter and the time response formula are determined according to the minimum value of mean relative error(MRE).Combined with the domestic natural gas annual consumption data,the classical model and the improved GM(1,1)model are applied to the calculation and error comparison respectively.It proves that the improved model is better than any other models. 展开更多
关键词 grey prediction GM(1 1)model background value grey system theory
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Comprehensive optimized GM(1,1) model and application for short term forecasting of Chinese energy consumption and production 被引量:8
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作者 Ning Xu Yaoguo Dang Jie Cui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期794-801,共8页
In order to improve prediction accuracy of the grey prediction model and forecast China energy consumption and production in a short term, this paper proposes a novel com- prehensively optimized GM(1,1) model, also ... In order to improve prediction accuracy of the grey prediction model and forecast China energy consumption and production in a short term, this paper proposes a novel com- prehensively optimized GM(1,1) model, also named COGM(1,1), based on the grey modeling mechanism. First, the relationship of the background value formula and its whitenization equation is analyzed and a new method optimizing background values is proposed to eliminate systemic errors in the modeling process. Second, the solving process of the new model is derived. For parameter estimation, a set of auxiliary parameters are used to change grey equation's form. Then, original parameters are re- stored by an equations system. After solving the whitenization equation, initial value in time response function is established by least errors criteria. Finally, a numerical case and comparison with other grey prediction models are made to testify the new model's effectiveness, and the computational results show that the COGM(1,1) model has a better property and achieves higher precision. The new model is used to forecast China energy con- sumption and production, and the ability of energy self-sufficiency is further analyzed. Results indicate that gaps between consump- tion and production in future are predicted to decline. 展开更多
关键词 COGM(1 1) grey prediction energy consumption background value.
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Main progress and prospect for China’s hydrogeological survey 被引量:4
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作者 WU Ai-min HAO Ai-bing +6 位作者 GUO Hai-peng LIU Jing-tao ZHANG Er-yong WANG Huang WANG Xin-feng WEN Xue-ru ZHANG Cui-guang 《Journal of Groundwater Science and Engineering》 2020年第3期195-209,共15页
This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeologic... This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeological survey in the“14th Five-year Plan”.The significant progress includes:China established the 1:50000 standard hydrogeological survey system with Chinese characteristics and produced the new generation of highquality hydrogeological maps;the national groundwater monitoring project was completed and accepted,which marks China taking the leading position in groundwater monitoring internationally;fruitful results were achieved in the national groundwater quality survey,and groundwater quality background values were basically identified and checked;hydrogeological and environmental geological survey was continuously promoted in karst areas and the ecological restoration of rocky desertification achieved remarkable results;China strengthened layer exploration techniques for groundwater,integrating the key and practical techniques of layer exploration and monitoring;the exploration of groundwater in the poverty-stricken regions and old revolutionary base areas were effectively promoted to strongly guarantee the poverty alleviation and drinking water safety;the mystery of desert groundwater was uncovered,making up for the shortage of 1:250000 hydrogeological survey in the Badain Jaran Desert;and more efforts were made to conduct survey on the water resources in the basin,and to finish the unified measurement of national-scale groundwater level. 展开更多
关键词 Hydrogeological survey National Groundwater Monitoring Project Groundwater quality background values Ecological restoration of rocky desertification China
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Persistence of Organic Pesticide HCH in Waters
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作者 Yang Dongfang Zhu Sixi +2 位作者 Wang Fengyou Wang Yi Yang Xiuqin 《Meteorological and Environmental Research》 CAS 2014年第3期42-45,共4页
[Objective]The research aimed to study HCH persistence in Jiaozhou Bay.[Method]Based on the investigation data in Jiaozhou Bay in April,August,September and October of 1989,we analyzed the source,distribution and migr... [Objective]The research aimed to study HCH persistence in Jiaozhou Bay.[Method]Based on the investigation data in Jiaozhou Bay in April,August,September and October of 1989,we analyzed the source,distribution and migration status of HCH in sea area of Jiaozhou Bay.By using structural model of HCH environmental background value in Jiaozhou Bay,basic background value,input amount of terrestrial runoff and environmental background value of HCH in Jiaozhou Bay were calculated.[Result]Basic background value of HCH in water area of Jiaozhou Bay was 0.012 7μg/L,HCH input amount of terrestrial runoff was during 0-0.057 1μg/L,HCH content input by ocean current was 0μg/L.Then,environmental background value of HCH in water area of Jiaozhou Bay was during 0.012 7-0.069 8μg/L.[Conclusion]HCH needed long time migrating from land to sea bottom,and experienced terrestrial migration process,water migration process,settlement process and biological migration cycle process.In these migration processes,HCH was persistent,and always caused threats and harms on organism. 展开更多
关键词 HCH PERSISTENCE Environmental background value Biological migration cycle Jiaozhou Bay China
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Application of Environmental Geophysical Prospecting in Environmental Quality Investigation of Reclaimed Land
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作者 Taicong CHEN Hong WU +1 位作者 Haifeng HUANG Ruirui SUN 《Meteorological and Environmental Research》 CAS 2020年第3期81-85,共5页
Traditional geophysical prospecting methods( electromagnetic induction method,high-density resistivity method and ground penetrating radar method) were applied to the environmental quality detection of reclaimed land ... Traditional geophysical prospecting methods( electromagnetic induction method,high-density resistivity method and ground penetrating radar method) were applied to the environmental quality detection of reclaimed land in the "198" area of Shanghai. According to the results of drilling sampling and laboratory analysis,the accuracy,suitability and consistency of theses geophysical prospecting methods were evaluated. 展开更多
关键词 "198"area Reclaimed land Geophysical prospecting method background value
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