Li Q.,China National Environmental Monitoring Center |
Wang E.,University of North Dakota |
Hu H.,The Environmental Protection Information Center
Water, Air, and Soil Pollution | Year: 2017
China’s rapid industrialization and urbanization has come at a staggering cost to the environment. In recent years, urban air pollution has been a serious environmental issue in Chinese cities that often hits news headlines in China and abroad. Based on the most recent data available, this paper employs two indices to examine the spatial and temporal patterns of some major air pollutants, including sulfur dioxide (SO2), nitrogen dioxide (NO2), zone (O3), inhalable particulate matter (PM10), and fine particulate matter (PM2.5), in China’s major cities and city regions. The results show that these pollutants display distinct spatial and seasonal variations. Overall, air pollution is much more serious in northern parts of the country, especially in large cities and a few major urban agglomerations, but we also find concentrations of air pollutants in urban agglomerations in southern China. Seasonally, Chinese cities suffer from air pollution especially PM2.5 pollution most in winter while summer is the cleanest season for most cities. Regional variations exist in composition of leading air pollutants and in influencing factors. Meteorological factors, such as wind speed, precipitation, temperature, air pressure, and relative humidity, often have important impacts on PM2.5 concentration, though their specific contributions vary across different cities. We argue that effective air pollution control policies should be regional in nature, but cross-border cooperation between regional and local governments is essential in order to tackle the problem of air pollution more effectively. © 2017, Springer International Publishing Switzerland.
Wang F.,Tongji University |
Li S.,The Environmental Protection Information Center |
Huang M.,The Environmental Protection Information Center
Proceedings - 2016 IEEE International Conference on Internet of Things; IEEE Green Computing and Communications; IEEE Cyber, Physical, and Social Computing; IEEE Smart Data, iThings-GreenCom-CPSCom-Smart Data 2016 | Year: 2017
The purpose of this paper is to estimate an index that can reflect public emotions towards environmental status based on micro-blog data. We first analyze the micro-blog data by emotion classification and sentiment analysis techniques to obtain people's positive/negative emotional level about their surrounding environmental conditions. Afterwards, the correlation between an emotional index and the air quality index (AQI) collected from air monitoring stations is evaluated. Such an emotional index hence can potentially be included in future environmental management solutions, for instance, as feedbacks from the public after certain environment protection policies are conducted or as an extra reference for pollution detection. © 2016 IEEE.
Xu L.,Beijing Normal University |
Yin H.,Beijing Normal University |
Li Z.,Beijing Normal University |
Li S.,The Environmental Protection Information Center
International Journal of Environmental Research and Public Health | Year: 2014
As the land ecosystem provides the necessary basic material resources for human development, land ecological security (LES) plays an increasingly important role in sustainable development. Given the degradation of land ecological security under rapid urbanization and the urgent LES requirements of urban populations, a comprehensive evaluation method, named Double Land Ecological Security (DLES), has been introduced with the city of Guangzhou, China, as a case study, which evaluates the LES in regional and unit scales for reasonable and specific urban planning. In the evaluation process with this method, we have combined the material security with the spiritual security that is inevitably associated with LES. Some new coefficients of land-security supply/demand distribution and technology contribution for LES evaluation have also been introduced for different spatial scales, including the regional and the unit scales. The results for Guangzhou indicated that, temporally, the LES supply indices were 0.77, 0.84 and 0.77 in 2000, 2006 and 2009 respectively, while LES demand indices for the city increased in 2000, 2006 and 2009 from 0.57 to 0.95, which made the LES level decreased slowly in this period. Spatially, at the regional scale, the urban land ecological security (ULES) level decreased from 0.2 (marginal security) to −0.18 (marginal insecurity) as a whole, in unit scale, areas in the north and in parts of the east were relatively secure and the security area was shrinking with time, but the central and southern areas turned to be marginal insecurity, especially in 2006 and 2009. This study proposes that DLES evaluation should be conducted for targeted and efficient urban planning and management, which can reflect the LES level of study area in general and in detail. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Xu L.Y.,Beijing Normal University |
Xie X.D.,Beijing Normal University |
Li S.,The Environmental Protection Information Center
Environmental Pollution | Year: 2013
This study combines the methods of observation statistics and remote sensing retrieval, using remote sensing information including the urban heat island (UHI) intensity index, the normalized difference vegetation index (NDVI), the normalized difference water index (NDWI), and the difference vegetation index (DVI) to analyze the correlation between the urban heat island effect and the spatial and temporal concentration distributions of atmospheric particulates in Beijing. The analysis establishes (1) a direct correlation between UHI and DVI; (2) an indirect correlation among UHI, NDWI and DVI; and (3) an indirect correlation among UHI, NDVI, and DVI. The results proved the existence of three correlation types with regional and seasonal effects and revealed an interesting correlation between UHI and DVI, that is, if UHI is below 0.1, then DVI increases with the increase in UHI, and vice versa. Also, DVI changes more with UHI in the two middle zones of Beijing. © 2013 Elsevier Ltd. All rights reserved.
Chen Y.-X.,The Environmental Protection Information Center
Shenyang Gongye Daxue Xuebao/Journal of Shenyang University of Technology | Year: 2017
In order to solve the low security problem caused by the fact that it is difficult to reduce effectively the closeness between adjacent pixels because of the periodicity in the scrambling process for the current image encryption algorithms, an image encryption algorithm based on scrambling switching decision mechanism coupling with dynamic harmony search was proposed. The plain text was divided into equal image sub-blocks, and a random array group was obtained through Logistic mapping. In addition, the scrambling switching decision mechanism was defined, and the sub-blocks were permutated through selecting the appropriate scrambling function according to the switching parameters. The closeness between the image entropy and adjacent pixels was taken as the objective function, and was used to replace the traditional harmony search model. Through improving the optimal secret key exported by the harmony search mechanism and performing the repeated searching and optimization, the smallest closeness between adjacent pixels was obtained. The results show that compared with the current image encryption techniques, the proposed algorithm has higher security as well as better shear and differential attack resistances. © 2017, Editorial Department of Journal of Shenyang University of Technology. All right reserved.
Chang H.,Tsinghua University |
Wu Z.-X.,Tsinghua University |
Guo S.-Y.,The Environmental Protection Information Center |
Yang X.-T.,Tsinghua University
Annals of Nuclear Energy | Year: 2015
An optimized process for tritium-containing waste water collection of Higherature Gas-cooled Reactor (HTGR) was developed and experimentally verified using the 10 MW Higherature Gas-cooled Reactor-test module (HTR-10). Compared with the previous process, an auxiliary molecular sieve bed was added in helium purification regeneration system and new operation process was proposed to collect tritium-containing waste water. In this paper, the optimized process and verification experiment were presented in detail. In commissioning experiment of the improved HTR-10, a large quantity of high-dose tritium-containing waste water was successfully collected in the water separator of helium purification regeneration system, with the specific activity being 6.1 × 109 Bq/L. The verification experiment confirms that the optimized process is effective and reliable for the demonstration plant design of High Temperature Gas-cooled Reactor-Pebble bed module (HTR-PM) to avoid the large emission of detrimentally radioactive waste water to the environment. © 2015 Elsevier Ltd. All rights reserved.
Wu X.,Fuzhou University |
Cai W.,The Environmental Protection Information Center
2012 2nd International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2012 - Proceedings | Year: 2012
Environmental quality evaluation (EQE) is an important task of environmental protection. A large number of evaluation models have been developed for many environmental domains, such as water environmental quality of rivers, lakes and sea, air quality and environmental noise situation. Traditional EQE involves a complicate process which consists of data collection, data transmission, quality evaluation, evaluation result correction and publication, and it needs mass manual work. Along with people's more concerning with environmental status, it requires more powerful technique to accelerate the process of EQE. Hence all kinds of elements of EQE (data, environmental standard, evaluation method, human, etc.) need to be organized together to collaborate with each other. This paper presents an environmental quality evaluation and information service system to facilitate the EQE process, which utilizes grid computing technology to construct the basic IT infrastructure. The core functions such as data management, evaluation and information sharing are built as grid services to achieve more flexibility and extensibility. This system has been implemented and running in Sanming city of China and the effect is quite promising. © 2012 IEEE.
Zhang B.,The Environmental Protection Information Center |
Qin Y.,The Environmental Protection Information Center |
Huang M.,The Environmental Protection Information Center |
Sun Q.,The Environmental Protection Information Center |
And 3 more authors.
Computers and Geosciences | Year: 2011
System dynamics (SD) is well suited for studying dynamic nonlinear complex systems. In this paper, SD is applied to a rapid-onset water pollution accident using a 1-D water quality model and a conceptual GIS-SD framework is constructed to simulate the temporal-spatial changes of pollutant concentration. Based on the component GIS and the SD model, a prototype system of water quality simulation in water pollution accidents is developed. The data collected on the spot in the Songhua River water pollution accident in November 2005 were used for model parameter calibration and model validation. The results showed that: (1) the constructed model could simulate the changes of nitrobenzene concentration with time in the Songhua River water pollution accident, especially during the peak concentration and at the arrival time of peak concentration, and that the simulated values and the on-the-spot monitored values corresponded with each other well; (2) the scenario simulation could be made by adjusting parameters u (longitudinal current velocity), E (longitudinal diffusion coefficient), and k (decay rate coefficient). Such a model can provide decision makers with quantitative information to optimize related emergency response measures. © 2011.
Zhang B.,The Environmental Protection Information Center
Advanced Materials Research | Year: 2014
China is meeting many environmental challenges that threaten food safety and security but there are actions China may implement to improve this situation. Current impediments include continued population increase, rapid urbanization, and decrease in arable lands, water pollution and climate change. China should control the population, improve irrigation techniques, fight against water pollution and invest on education to facilitate a major transition in the development mode and strive for more sustainable consumption of natural resources. These actions will ensure China's self-sufficiency and prosperity. © (2014) Trans Tech Publications, Switzerland.