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Lu L.,Shanghai JiaoTong University | Wang C.,Tongji University | Deng W.,Shanghai JiaoTong University | Bing X.,Shenyang Urban Planning Design and Research Institute
Mathematical Problems in Engineering | Year: 2015

Public transit has been widely recognized as a potential way to develop low-carbon transportation. In this paper, an optimal allocation model of public transit mode proportion (MPMP) has been built to achieve the low-carbon public transit. Optimal ratios of passenger traffic for rail, bus, and taxi are derived by running the model using typical data. With different values of traffic demand, construction cost, travel time, and accessibilities, MPMP can generate corresponding optimal ratios, benefiting decision impacts analysis and decision makers. Instead of considering public transit as a united system, it is separated into units in this paper. And Shanghai is used to test model validity and practicality. © 2015 Linjun Lu et al. Source

Zhang H.,Tongji University | Teng J.,Tongji University | Jiang Y.,Shenyang Urban Planning Design and Research Institute | Yin Q.,Shanghai Dongtan International Wetland Co.
Journal of Southeast University (English Edition) | Year: 2014

Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons (PAHs) are analyzed. The results show that the heavy metal concentrations range within 0.50 to 51.80 (As), 0 to 20.80 (Se), 13.67 to 445.80 (Zn), 0 to 44.20 (Pb), 0 to 15.80 (Ni), 39.58 to 264.20 (Fe), 0 to 253.00 (Mn), 0 to 8.20 (Cr), 0 to 124.20 (Cu), and 159.83 to 536.40 μg/L (Al). Se, Pb, Mn and Al concentrations in most samples exceed their corresponding criterion continuous concentrations (CCCs), while Zn and Cu concentrations exceed their criterion maximum concentrations (CMCs). The concentrations of ΣPAHs range within 37.25 to 114.57 ng/L and concentrations of PAHs are all below their corresponding CCCs. Cu, Zn and ΣPAHs show the first flush phenomenon. Analysis results of the modified Nemerow index method (NIM) indicate that runoff from eight rainfall events may have very strong biological toxicity effects, four have strong effects, three have moderate effects and only two have insignificant effects. Therefore, it is concluded that urban highway runoff is a significant pollution source to aquatic ecosystems and needs immediate purification. © Copyright. Source

Chen R.-H.,Tongji University | Li F.-P.,University of Shanghai for Science and Technology | Zhang H.-P.,Tongji University | Jiang Y.,Shenyang Urban Planning Design and Research Institute | And 3 more authors.
Science of the Total Environment | Year: 2016

In this study, comparative analyses of highway runoff samples obtained from seventeen storm events have been conducted between the traditional water quality assessment method and biotoxicity tests, using zebrafish (Danio rerio) embryos and luminous bacteria (Vibrio qinghaiensis. Q67) to provide useful information for ecotoxicity assessment of urban highway runoff. The study results showed that the Nemerow pollution index based on US EPA recommended Criteria Maximum Concentrations (CMC) (as traditional water quality assessment method) had no significant correlation with luminous bacteria acute toxicity test results, while significant correlation has been observed with two indicators of 72 hpf (hours post fertilization) hour hatching rate and 96 hpf abnormality rate from the toxicity test with zebrafish embryos. It is therefore concluded that the level of mixture toxicity of highway runoff could not be adequately measured by the Nemerow assessment method. Moreover, the key pollutants identified from the water quality assessment and from the biotoxicity evaluation were not consistent. For biotoxic effect evaluation of highway runoff, three indexes were found to be sensitive, i.e. 24 hpf lethality and 96 hpf abnormality of zebrafish embryos, as well as the inhibition rate for luminous bacteria Q67. It is therefore recommended that these indexes could be incorporated into the traditional Nemerow method to provide a more reasonable evaluation of the highway runoff quality and ecotoxicity. © 2016. Source

Zhang X.,Liaoning Normal University | Wang F.,Liaoning Normal University | Cui Y.,Shenyang Urban Planning Design and Research Institute
Journal of Geomatics | Year: 2015

To be specific, data layer is the server side of the system the function of which is to manage all system data such as network data with Geodatabase group integration. On the other hand the client side of the system is constructed by presentation layer and business logic layer. The two layers have been developed by ArcEngine component interfaces and interface controls. The basic functions of GIS, pipe visualization, network analysis and 3D terrain analysis could be successfully achieved by presentation layer and business logic layer. This paper has introduced the key technologies and function interface of main functions. Source

Wu L.,Tongji University | Jiang Y.,Shenyang Urban Planning Design and Research Institute | Zhang L.,Tongji University | Chen L.,Tongji University | Zhang H.,Tongji University
Environmental Science and Pollution Research | Year: 2014

Pollution from urban highway runoff has been identified as one of the major causes of the deterioration of receiving water quality. The purpose of this study is to assess the toxicity of urban storm water samples in Shanghai using the zebrafish (Danio rerio) embryo test and the bacterial luminescence (Vibrio qinghaiensis) assay. The toxicity of highway runoff from seventeen storm events was investigated in both grab and composite samples. Zebrafish embryos were exposed to the runoff samples and development parameters including lethality, spontaneous movements in 20 s, heart beat rate, hatching rate, and abnormality of zebrafish embryos were observed after 24, 48, 72, and 96 h of exposure. Inhibition rates of luminescence intensity were also recorded. The results showed that in the zebrafish embryo toxicity tests, both grab and composite samples increased the lethality, reduced the percentage with spontaneous movements and heart beats, inhibited the hatching of embryos, and induced morphological abnormalities. In the Vibrio qinghaiensis toxicity test, all the grab samples inhibited the luminescence, while some of the composite samples promoted it, which indicated that different types of toxicants might have been affecting the species. The multivariate statistics analysis indicated that heavy metal (zinc, manganese, and copper) and PAHs might mainly contribute to the toxicity of runoff samples. © 2013 Springer-Verlag Berlin Heidelberg. Source

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