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Dynamic Variation of Land-use Types of the Constructed Wetland before and after Oil-field Water Irrigation Based on 3S Technology
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作者 CHEN Ming-hui ZHANG Chen +2 位作者 HU Yan SU Wei DONG De-ming 《Meteorological and Environmental Research》 CAS 2012年第12期71-76,共6页
[Objective] The study aimed at analyzing the dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation based on 3S technology. [Method] At semi-arid and arid areas in t... [Objective] The study aimed at analyzing the dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation based on 3S technology. [Method] At semi-arid and arid areas in the west of Jilin Province, water resource balance between the amount of oil-field water supply and ecological water requirement in the constructed wetland irrigated by oil-field water during 2001-2010 was investigated firstly. Afterwards, based on 3S technology, the partition and dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation in 2001, 2006, 2008 and 2010 were analyzed. [Result] The annual ecological water requirement of the constructed wetland from 2003 to 2010 varied from 1.62×106 to 2.24×106 m3, and the annual amount of oil-field water supply in the region changed from 2.12×106 to 2.84×106 m3, which showed that the supply amount of oil-field water could meet the basic ecological water requirement of the constructed wetland. Meanwhile, compared with 2001, the areas of water region and paddy field in 2010 increased by 2.3 and 10.0 times, and the areas of forest and marsh rose by 40.15% and 29.5.0% respectively. [Conclusion] Water shortage and ecological environment problem of arid and semi-arid areas had been improved by oil-field water irrigation. 展开更多
关键词 Constructed wetland Oil-field water irrigation 3S technology Land use Dynamic variation
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Coupled planning of water resources and agricultural land-use based on an inexact-stochastic programming model 被引量:3
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作者 Cong DONG Guohe HUANG +1 位作者 Qian TAN Yanpeng CAI 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第1期70-80,共11页
Water resources are fundamental for support of regional development. Effective planning can facilitate sustainable management of water resources to balance socioeconomic development and water conservation. In this res... Water resources are fundamental for support of regional development. Effective planning can facilitate sustainable management of water resources to balance socioeconomic development and water conservation. In this research, coupled planning of water resources and agricultural land use was undertaken through the develop- ment of an inexact-stochastic programming approach. Such an inexact modeling approach was the integration of interval linear programming and chance-constraint pro- gramming methods. It was employed to successfully tackle uncertainty in the form of interval numbers and probabil- istic distributions existing in water resource systems. Then it was applied to a typical regional water resource system for demonstrating its applicability and validity through generating efficient system solutions. Based on the process of modeling formulation and result analysis, the developed model could be used for helping identify optimal water resource utilization patterns and the corresponding agri- cultural land-use schemes in more, a number of decision three sub-regions. Further- alternatives were generated under multiple water-supply conditions, which could help decision makers identify desired management policies. 展开更多
关键词 water resources management regional water system PLANNING scenario analysis UNCERTAINTY
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A decomposition model to analyze effect of SO_2 emission density of China
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作者 张平淡 杜雯翠 +1 位作者 焦胜 何理 《Journal of Central South University》 SCIE EI CAS 2014年第2期701-708,共8页
A decomposition model was applied to study the resource-saving and environment-friendly effects of air pollutant emissions(taking industrial SO2 emission as an example) in China.From the results,it is found that 38.93... A decomposition model was applied to study the resource-saving and environment-friendly effects of air pollutant emissions(taking industrial SO2 emission as an example) in China.From the results,it is found that 38.93% and 61.07% are contributed to environment-friendly and resource-saving effects,respectively,by the dramatic decrease in industrial SO2 emission density(nearly 70% from 2001 to 2010).This indicates that China has achieved important progress during the 11th FYP(five-year plan) compared with the 10th FYP.A simultaneous equations model was also employed to analyze the influencing factors by using data from 30 provinces in China.The results imply that the influence of environmental regulation on environment-friendly effect is not obvious during the 10th FYP but obvious during the 11th FYP.Thus,the government should continue promoting the environment-friendly effect by further enhancing environmental regulation and strengthening the role of environmental management. 展开更多
关键词 two-oriented society air pollution control decomposition model environmental regulation SO2 emission
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A review of inexact optimization modeling and its application to integrated water resources management
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作者 Ran WANG Yin LI Qian TAN 《Frontiers of Earth Science》 SCIE CAS CSCD 2015年第1期51-64,共14页
Water is crucial in supporting people's daily life and the continual quest for socio-economic development. It is also a fundamental resource for ecosystems. Due to the associated complexities and uncertainties, as we... Water is crucial in supporting people's daily life and the continual quest for socio-economic development. It is also a fundamental resource for ecosystems. Due to the associated complexities and uncertainties, as well as intensive competition over limited water resources between human beings and ecosystems, decision makers are facing increased pressure to respond effectively to various water-related issues and conflicts from an integrated point of view. This quandary requires a focused effort to resolve a wide range of issues related to water resources, as well as the associated economic and environmental implications. Effective systems analysis approaches under uncertainty that successfully address interactions, complexities, uncertainties, and changing conditions associated with water resources, human activities, and ecological conditions are desired, which requires a systematic investigation of the previous studies in relevant areas. Systems analysis and optimization modeling for integrated water resources management under uncertainty is thus comprehensively reviewed in this paper. A number of related methodologies and applications related to stochastic, fuzzy, and interval mathematical optimization modeling are examined. Then, their applica- tions to integrated water resources management are presented. Perspectives of effective management schemes are investigated, demonstrating many demanding areas for enhanced research efforts, which include issues of data availability and reliability, concerns over uncertainty, necessity of post-modeling analysis, and the usefulness of the development of simulation techniques. 展开更多
关键词 inexact optimization STOCHASTIC fuzzy sets integrated water resources management UNCERTAINTY
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An inexact risk management model for agricultural land-use planning under water shortage
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作者 Wei LI Changchun FENG +3 位作者 Chao DAI Yongping LI Chunhui LI Ming LIU 《Frontiers of Earth Science》 SCIE CAS CSCD 2016年第3期419-431,共13页
Water resources availability has a significant impact on agricultural land-use planning, especially in a water shortage area such as North China. The random nature of available water resources and other uncertainties ... Water resources availability has a significant impact on agricultural land-use planning, especially in a water shortage area such as North China. The random nature of available water resources and other uncertainties in an agricultural system present risk for land-use planning and may lead to undesirable decisions or potential economic loss. In this study, an inexact risk management model (IRM) was developed for supporting agricultural land-use planning and risk analysis under water shortage. The IRM model was formulated through incorporating a conditional value-at-risk (CVaR) constraint into an inexact two-stage stochastic programming (ITSP) framework, and could be used to control uncertainties expressed as not only probability distributions but also as discrete intervals. The measure of risk about the second-stage penalty cost was incorporated into the model so that the trade-off between system benefit and extreme expected loss could be analyzed. The developed model was applied to a case study in the Zhangweinan River Basin, a typical agricultural region facing serious water shortage in North China. Solutions of the IRM model showed that the obtained first-stage land-use target values could be used to reflect decision-makers' opinions on the long-term devel- opment plan. The confidence level a and maximum acceptable risk loss fl could be used to reflect decision- makers' preference towards system benefit and risk control. The results indicated that the IRM model was useful for reflecting the decision-makers' attitudes toward risk aversion and could help seek cost-effective agricul- tural land-use planning strategies under complex uncer- tainties. 展开更多
关键词 agricultural land-use planning risk manage-ment CVAR UNCERTAINTY water shortage
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A QICAR Model for Metal Ion Toxicity Established via PLS Method 被引量:1
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作者 LI Yu JIANG Long LI Xiao-li HU Yan WEN Jing-ya 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第3期568-573,共6页
The partial least squares(PLS) method was employed to establish a quantitative ion characteristics-activity relationship(QICAR) model for metal ion toxicity(EC50 of 15 metal ions). The ion characteristics includ... The partial least squares(PLS) method was employed to establish a quantitative ion characteristics-activity relationship(QICAR) model for metal ion toxicity(EC50 of 15 metal ions). The ion characteristics included AN(the atomic number), AIP(the change in ionization potential, eV), Xm(the electronegativity, eV), AW(the atomic weight), Xm2r(the covalent index), △E0(the absolute difference between electrochemical potential of the ion and that of its first stable reduced state, eV), |lgKoH| (the absolute value of the lg of the first hydrolysis constant), AR(the atomic radius, nm), AR/AW(the ratio between atomic radius and atomic weight) and ap(the softness index) selected based on relative correlation analysis. The simulated and tested(with the other four metals) efficiency coefficients of the model are 0.88 and 0.96, respectively. The information revealed from the QICAR model indicates that the value of the metal ion toxicity was positively correlated with variables AN, AlP, Xm, AW and Xm2r; negatively correlated with variables AE0, |IgKoH|, AR/AW, AR and ap, and ion characteristics △E0, Xm, σp and Xm2r were found to contribute more to the toxicity of metal ions via the accurate analysis method provided by PLS. The model could be used to predict the toxicity of the target metals and preliminary to assess combined pollution and environmental risk for heavy metals in the environments. 展开更多
关键词 Quantitative ion characteristics-activity relationship Partial least square Metal ion characteristic Metal toxicity Accurate analysis
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Solvent Effect on Characteristic Vibration of IR Spectrum of 4,4'-Dibromodiphenyl Ether 被引量:1
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作者 LI Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第6期997-1004,共8页
The optimal geometry, IR spectrum and vibration assignment of 4,4'-dibromodiphenyl ether(BDE-15) in gas phase were calculated via the density functional theory(DFT) at the level of B3LYP/6-3 l+G(d). Based on t... The optimal geometry, IR spectrum and vibration assignment of 4,4'-dibromodiphenyl ether(BDE-15) in gas phase were calculated via the density functional theory(DFT) at the level of B3LYP/6-3 l+G(d). Based on the vi- bration assignment, the calculation of vibration frequencies and intensities of 5 main vibration types of BDE-15 in 25 kinds of solvents was carried out by means of a self-consistent reaction field(SCRF) theoretical model at the level of B3LYP/6-31+G(d) to analyze the solvent effect on the vibration of IR spectrum of BDE-15. To study the solvent ef- fect further, C--O asymmetric stretching vibration fluctuating, which is relatively acute in both vibration frequency and intensity, was selected as the characteristic vibration to establish different linear solvation energy relation(LSER) models for solvent categoring. Solvent parameters(a, /3, ~r*), acceptable number(AN) and quantitative structure- activity relationship(QSAR) models were established via chemical quantum parameters of solvent moleculer, which were first been introduced to investigate different solvent-solute interaction mechanisms in alcoholic and non-alcoholic solvents on molecular level. At last, a single solvent molecule was embedded in the framework of po- larizable continuum model(PCM) to validate the effect of hydrogen bonding on solvent-solute interaction in alcohol solvents. The obtained results show that 5 main vibration types of BDE-15 in different solvents have small variation range in frequency and intensity and all the vibration frequencies in solvents are lower than those in gas phase, de- creasing along with the increasing of the dielectric Constant(e) of solvents exponentially. In contrast, all the vibration intensities in solvents are greater than those in gas phase and present positive exponential trend. Twenty-five solvents were divided into two categories(non-alcoholic solvents and alcoholic solvents) by LSER. The CmO asymmetric stretching vibration was mainly regulated by non-specific interaction(dipole-dipole and dipole-induced dipole inter- action) and the combination of non-specific interaction and electronic effect in non-alcoholic solvents and alcoholic solvents, respectively, R2 values of the two QSAR models established for different categories are 0.940 and 0.997, both showing good fitness and the decisive parameters for the two models are/~, a= and aye, EHOMO separately, which reflect that the interaction mechanism is coincide with the conclusion obtained by LSER model. The present of hy- drogen bonding in alcoholic solvents improves the differentiation degree of vibration frequency of the two models with the variance increasing from 0.281 to 0.513 and the intensity from 5.263 to 10.382, which is conducive to the identification of polybrominated diphenyl ether(PBDE) homologues, indicating this research would provide theoreti- cal gist for linking the experimental IR spectrum data with the identification of PBDE homologues. 展开更多
关键词 Solvent effect IR spectrum Vibration assignment Quantitative structure-activity relationship HYDROGENBONDING
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An uncertain energy planning model under carbon taxes
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作者 Hongkuan ZANG Yi XU +2 位作者 Wei LI Guohe HUANG Dan LIU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第4期549-558,共10页
In this study, an interval fuzzy mixed-integer energy planning model (IFMI-EPM) is developed under considering the carbon tax policy. The developed IFMI- EPM incorporates techniques of interval-parameter programming... In this study, an interval fuzzy mixed-integer energy planning model (IFMI-EPM) is developed under considering the carbon tax policy. The developed IFMI- EPM incorporates techniques of interval-parameter programming, fuzzy planning and mixed-integer programming within a general energy planning model. The IFMIEPM can not only be used for quantitatively analyzing a variety of policy scenarios that are associated with different levels of carbon tax policy, but also tackle uncertainties expressed as discrete intervals and fuzzy sets in energy and environment systems. Considering low, medium and high carbon tax rates, the model is applied to an ideal energy and environment system. The results indicate that reasonable solutions have been generated. They can be used for generating decision alternatives and thus help decision makers identify desired carbon tax policy. 展开更多
关键词 ENERGY carbon tax PLANNING UNCERTAINTY FUZZY
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