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Heavy metals in water, soils and plants in riparian wetlands in the Pearl River Estuary, South China

Procedia Environmental Sciences 2010年 2卷 1344-1354页

作者： Honggang Zhang Baoshan Cui Rong Xiao Hui Zhao State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

Samples collected from sites of 26 for water, soils and two native plants (Scirpus tripueter Linn. and Cyperus malaccensis Lam.) in riparian wetlands were analyzed to investigate the distribution of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in Panyu-Nansha area of Pearl River estuary. The results indicated that concentrations of heavy metals among three compartments were in the order: soils > plants > water and no obvious correlations were found between in soils and water, water and plants. Pb is the only metal accumulated in both plants that correlated with its concentrations in soils. The weak or lack correlations among metals in water, soils and plants suggest that other factors existed influence the metal uptake and storage in plants other than absorbing from soils and water. The plants had the same trend in metal accumulation that was Cd > Zn > Cu > Ni > Cr > Pb. The translocation factors showed that metals accumulation was mostly occurred in roots for these two plants. Compared to the other heavy metals, Cd seemed to be much more hazardous. Principal Component analysis and Cluster analysis were used to analyze the relevance of different metals and identify the major sources. The results showed two factors dominated the metals variability (83.4% of total variance) that Cd and Pb, were dominated by PC1 whereas Cr, Cu and Ni charged by another factors and Zn was affected by both two components. Analysis of CA for the sampling sites showed that among all of anthropogenic pollutions, industrial wastewater was major sources of heavy metals especially for Cd, Cr, Cu and Zn in the PRE.

关键词： Riparian wetlands Heavy metals Pearl River estuary Panyu-Nansha area

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Response of Freshwater Biofilm to pollution and ecosystem in Baiyangdian Lake of China

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Procedia Environmental Sciences 2010年 2卷 1759-1769页

作者： Wang Xuemei Liu Jingling Ma Muyuan Yang Zhifeng State Key Joint Laboratory of Environmental Simulation and Pollution Control & School of Environment Beijing Normal University 100875 Beijing China

An experimental study was undertaken to highlight the potential applicability of biofilms as biomonitors forming simultaneously on natural and artificial substrata in Baiyngdian Lake(China).We investigated the responses of freshwater biofilm in 8 site of Baiyngdian Lake and compared with control site (a reservoir) to assess the relative health of water. Exposure to pollution and its impact on biofilms were assessed by measuring the biomass production, Chlorophyll concentration, the algal composition, extracellular enzyme activity of bacterial communities and Polysaccharide content. This relation between the biological characters of biofilms and water quality were discussed, and the relative health of regions were demonstrated by the degree of deviation based on bioflim indicator in the following order: Fu river (S4) < Duan cun (S8) < Nan Liuzhuang (S5) < Wang jiazai (S1) < Cai putai (S7) < Zao lingzhuang (S2)< Shao Chedian (S3).. The result indicated that biofilm can provide information for pollution detection and ecological health assessment of water, and biofilm on aritificial substrata was recommended for biomonitoring in the Baiyangdian Lake.

关键词： Freshwater biofilm community analyses Biomonitoring Substrata

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Emergy-based urban ecosystem health evaluation of the Yangtze River Delta urban cluster in China

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Procedia Environmental Sciences 2010年 2卷 689-695页

作者： Meirong Su State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

An evaluation framework of emergy-based urban ecosystem health indicators was established to measure and describe the urban ecosystem health status in terms of energy and materials metabolism, when combing with the classical urban ecosystem health factors. Set pair analysis was also employed to guarantee and promote the objectivity of the ecosystem health criteria. Set pair analysis defines the approximate degree of a real index set relative to an optimal index set, and this is evaluated to describe the relative health levels of urban ecosystems based on the emergy indicators. Six cities in the Yangtze River Delta urban cluster in China were selected as case studies using 2005 data, and the relative urban ecosystem health levels were evaluated using the emergy indicators and set pair analysis. The evaluation showed that the urban ecosystem health states of Shanghai and Hangzhou are relatively good, while the health states of Wuxi and Suzhou are relatively poor. The health states for the cities based on concrete factors were also analyzed to identify regulatory directions for the improvement of the health status of those cities with relatively poor ecosystem health. This paper presents a meaningful comparison between different urban ecosystems at different indicator levels, and provides a useful framework for urban ecological management with respect to urban ecosystem health status.

关键词： Ecosystem health urban cluster emergy relativity Yangtze River Delta

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Implication of Ecosystem Health Assessment for Urban Management

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Procedia Environmental Sciences 2010年 2卷 674-680页

作者： Meirong Su Bin Chen Zhifeng Yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

In order to implementing theoretical urban ecosystem health assessment into practical urban management more effectively, it is necessary to find out the relationship between the urban ecosystem health status based on the internal metabolism characteristics and the external performance of the urban ecosystem. Eleven indicators are selected to describe the performance of the urban ecosystem from aspects of resources condition, social civilization, economic development and environmental load. The correlation analysis between the emergy-based urban ecosystem health status in view of energy and material flows and the ecosystem status based on the eleven indicators is conducted to reveal the relationship between the internal biophysical foundation and the external performance of the urban ecosystem. It is indicated that the resources basis and the economic development level correlate with the emergy-based urban ecosystem health status, which implies the measurement of effectively and reasonably utilizing and exploiting resources, adjusting the economic development pattern and industrial structure should be paid much attention to improve the urban ecosystem health level and optimize the urban ecosystem management.

关键词： Ecosystem health assessment indicator energy and materials flow correlation analysis urban ecosystem management

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Integrated control of Active Front Steering and Electronic Stability Program

Integrated Control of Active Front Steering and Electronic S...

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The 2nd IEEE International Conference on Advanced Computer control(第二届先进计算机控制国际会议 ICACC 2010)

作者： Jianhua Guo Liang Chu Hongwei Liu Mingli Shang Yong Fang State Key Laboratory of Automobile Dynamic Simulation.Jilin University Changchun 130025 P.R.China

ISBN: (纸本)9781424458455;9781424458486;9781424458479;9781424458462

In this paper, an integrated vehicle dynamics control system is designed to improve vehicle handling and stability by coordinating control of Active Front Steering (AFS) and Electronic Stability Program (ESP). The integrated control system includes a coordinated controller in upper layer and two subsystem controllers in lower layer. The controlalgorithm based on β -β phase plane is used to identify the driving situations. And a coordinated control rule based on integrated scheme is employed to determine and allocate the control tasks between the two subsystems. The simulation results show that the proposed control strategy is able to enhance the tracking performance of the reference yaw rate and improve the driving steer-ability of the vehicle.

关键词： Vehicle Integrated control Active front steering Electronic stability program

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Change of urban ecosystem development—A case study of Beijing, China

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Procedia Environmental Sciences 2010年 2卷 681-688页

作者： Zhifeng Yang Meirong Su Bin Chen State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

Considering its characteristics in terms of structure, function, performance and evolution, the urban ecosystem can be regarded as a vital organism. Based on the concept of urban vital organism, the framework of urban vitality index covering producing power, living status, ecological ascendancy and vital force, is constructed to represent the urban ecosystem development status from the economic subsystem, social subsystem, natural subsystem and ecological regulatory subsystem, respectively. Meanwhile, set pair analysis, an assessment method which can link different objects and describe their relationships, was combined with the urban vitality index to evaluate the relative urban ecosystem development levels. Choosing the situation of Beijing city from 1986 to 2005 as the case, the change of urban ecosystem development levels during the period were analyzed, by using the relative assessment model based on urban vitality index. Based on the results of the urban vitality index and its each factor, the change of urban ecosystem development on the scales of the whole ecosystem and each studied subsystems can be revealed, which implies the focus of urban ecological planning and management in the future.

关键词： Ecosystem development vital organism urban vitality urban ecosystem management Beijing city

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Analysis of influence of steering system on vehicle straight line

Analysis of influence of steering system on vehicle straight...

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WASE International Conference on Information Engineering, ICIE

作者： Hai, Chenguang Ji, Peng Yu, Haifeng State Key Laboratory of Automobile Dynamics Simulation Jilin University Changchun 130025 China Hebei University of Engineering Handan 056001 China BeiQi Foton Motor Co. Ltd. Zhu Cheng Plant Technology Center Zhucheng 262200 China

ISBN: (纸本)9780769540801

In Steer Release condition, due to the ability of actual vehicle to resist external small perturbations and self-Adaptive coordination can't be described in the previous vehicle model, the stability of vehicle is described insufficiently. A fine steering system model was established, including Stick-slip friction model and a complete dynamic system consist of wheels, axles, steering tie rod and rack. When encountered with outside interference input, the left and right wheels have the ability to coordinate with each other and ensure the stability of vehicle. The validity of the model is verified through the simulation of typical operating conditions and the fidelity of vehicle model is improved. © 2010 IEEE.

关键词： Stick-slip

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Study on Cycle-To-Cycle Variations of CAI Combustion Using NVO Strategy

Study on Cycle-To-Cycle Variations of CAI Combustion Using N...

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International Conference on Logistics Engineering and Intelligent Transportation Systems (LEITS)

作者： Hua Li Yingnan Guo Peng Cheng Fafa Liu Enwei Jiang State Key Laboratory of Automobile Dynamic Simulation Jilin University Changchun China Engine Design Department Changchun China

Based on the application of self-developed electro-hydraulic variable valve train (VVT), controlled Auto-Ignition(CAI) was achieved with Negative Valve Overlap (NVO) strategy. This VVT system that replaced the original camshaft was mounted on the head of a modified single cylinder engine. The cycle-to-cycle variation of CAI Combustion was investigated under several different operating points with 100 consecutive cycles sampled and stored. The experimental results indicated that as the excess air coefficient increases, with fixed engine speed and valve event, the coefficient of variation of indicated mean effective pressure (CoV IMEP ) dropped firstly and then increased. The CoV IMEP had the minimum value when the excess air coefficient ranges from 1.1 to 1.3. The engine speed and the valve lift showed the potential to influence CoV IMEP . Increased engine speed led to a more intense mixing progress, which introduced high intensity turbulence into the cylinder and resulted in a higher level of charge homogeneity at the end of compression stroke, and finally a steady CAI combustion. Meanwhile, decreasing the valve lift had a relatively minor effect. The variation of IMEP was consequently suppressed to some extend.

关键词： Valves Combustion Computer aided instruction Ignition Fuels Timing

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key nodes and corridors identifying method for large-scale evacuation network based on information centrality

Key nodes and corridors identifying method for large-scale e...

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2010 2nd International Conference on Future Computer and Communication, ICFCC 2010

作者： Jiang, Guiyan Wu, Zhengyan Li, Qiao Zhang, Chunqin State Key Lab. of Automotive Dynamic Simulation College of Automobile Jilin University Changchun China Traffic Information Engineering and Control College of Transportation Jilin University Changchun China Department of Foreign Language and Literature College of Changcheng China University of Geosciences Baoding China

ISBN: (纸本)9781424458226

Large-scale natural or man-made disasters have the potential to cause great loss of life, human injury and extreme property damage. Evacuation from areas at risk is often one of the most feasible strategies that can be undertaken in response to these types of disasters. Evacuating a large population in the shortest possible time is an extremely complicated and difficult task, which primarily relies on efficient method of traffic planning for emergency evacuation. This paper puts forward a novel method of identifying key nodes and corridors for emergency evacuation based on information centrality, the characteristic of which integrates a method of identifying the efficient nodes and the critical connectivity nodes for evacuation, and a method of identifying the key evacuation corridors. In addition, the approach of connectivity key nodes has been proposed. The experiment results show that the proposed method has rationality and feasibility. ©2010 IEEE.

关键词： Disasters

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Notice of Retraction: Analysis on influence of suspension compliance characteristics by unsymmetrical rubber bushing

Notice of Retraction: Analysis on influence of suspension co...

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International Conference on Computer Engineering and Technology, ICCET

作者： Ji Peng Lu Pingping Hai Chenguang Hebei University of Engineering Handan China State Key Laboratory of Automobile Dynamics Simulation Jilin University Changchun China

This article has been retracted by the publisher.

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