Showing 10 results for Air Pollution
Ruhollah Namaki, Akbar Abdollahzadeh Tarf, Hassan Sattari Sarbangholi,
Volume 0, Issue 0 (3-1921)
Abstract
Air pollution and adverse effects of pollution caused by the combustion of fossil fuels in urban settlements are among the important environmental issues of metropolises that need to pay attention to ways to reduce air pollution in cities. Global experience has shown that urban form indicators are one of the most important factors affecting air pollution and energy consumption in the city. Therefore, paying attention to the form of the city plays an important role in the long-term perspective of cities for better air quality. The present study is applied in terms of purpose and descriptive-analytical in terms of method. In order to collect the required data and information, library and documentary methods have been used. To analyze the data and answer the research questions, the Moran statistical technique was used in the GIS software environment. The results of this study showed that the air pollution situation in Tabriz in terms of air pollutants, ie sulfur dioxide, nitrogen dioxide, carbon monoxide in the second half of the year is more than the first half of the year, so that among the air monitoring stations The field had the highest number of air pollution. Also, the results of the study of the effect of urban form and land use pattern on air pollution showed that urban form and land use are effective on air pollution.
Ms Atefeh Bosak, Dr Zahra Hejazizadeh, Dr Akbar Heydari Tashekaboud,
Volume 0, Issue 0 (3-1921)
Abstract
Air pollution has significant impacts on human health, environmental quality, and the sustainable development of cities. This study aimed to evaluate PM10 using meteorological data from the city of Ahvaz through statistical methods and artificial neural networks. Daily meteorological data and air quality control station data for 4485 days (from 2011 to 2023) were obtained from the National Meteorological Organization and the Khuzestan Department of Environment. Initially, the data were processed and refined, and their normality was assessed using the Kolmogorov-Smirnov test. Given the non-normality of the data, Spearman's and Kendall's Tau-b methods were employed to examine their correlations. The time series and statistical information of the data were obtained using Python programming language. Furthermore, to predict future PM10 levels, the Multilayer Perceptron (MLP) neural network method was utilized. The results of these analyses indicated a significant correlation between meteorological variables and PM10. The Spearman and Kendall Tau-b correlations showed that PM10 had a positive and significant correlation with wind speed (0.094 and 0.061) and temperature (0.284 and 0.187) at a 99% confidence level. Conversely, PM10 exhibited a negative and significant correlation with visibility (-0.408 and -0.300), wind direction (-0.048 and -0.034), precipitation (-0.159 and -0.125), and relative humidity (-0.259 and -0.173) at the 99% confidence level. For future PM10 predictions, the MLP neural network was used. The model was of the Sequential type with an input layer consisting of 6 neurons, three hidden layers of Dense type with 16, 32, and 64 neurons, and an output layer with a linear activation function. The mean squared error (MSE) for the training set was 0.0034, and for the validation data, it was 0.0012. For the test set, the obtained validation accuracy was mse_mlp=0.0048 and val_loss=0.0012. The results indicate a significant direct or inverse correlation between meteorological data and PM10. Additionally, the outcomes of the MLP neural network demonstrated that the network provided satisfactory performance and acceptable predictions for PM10 data in Ahvaz.
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Volume 17, Issue 47 (12-2017)
Abstract
Suspended particles management is one of the important issues in controlling the air pollution of cities. These particles cause and develop heart and respiratory diseases in people. Mashhad is considered as one of the main and populous cities of Iran. Because of its climatic conditions and its tourism, the city is at the highest risk of this type of pollution. We attempted to use the multi-layer perceptron (MLP) artificial neural network and a Markov chain model to predict PM10 concentrations the city. We applied hourly data of CO, SO2, PM2.5 and temperature in late March and April 2015. Out of 1488 data series, 1300 data were used for network training and 188 data were used for validation. The results indicated the optimal performance of these methods in predicting of the amount of pollutants and also the probability of occurrence of hours with different quality of contamination. The best MLP artificial neural network model predicted the amount of pollutant particles with a coefficient of determination (R2) 0.88, index of agreement of 0.91 and a mean square error of 2.26. Also, the Markov model with average absolute error predicted about 0.1 percent of the probability of transferring the condition and the continuation of different states of air pollution caused by suspended particles.
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Volume 19, Issue 52 (3-2019)
Abstract
One of the Challenging problems of Tehran metropolitan region is Air pollution. Suburban expansion in the form of sprawl patterns have created the travels and transportations, due to the dependence on personal vehicles contributes more than 85 percent of creators of air pollution. The article studied the role of transportation in emergence of urban air pollution in Tehran metropolitan region, have population more than 15.98 million. The method of this paper is of analytical and is based on the secondary data and traditions of the Quantitative research methodology. This article have been wrote in the context of Retroductive strategy and meta-analysis method and compositional research traditions. For analysis of suburban spatial transportation have used Raw Data Intra-Urban and suburban Data in 1395 Year And for spatial analysis of air pollution (PM2.5 and PM10), have been used The raw data from sensing stations and Landsat satellite images (OLI) for three selected days in 1392, 1393, and 1395 as survey samples in the ArcGIS software. The research findings indicate that due to the intensity of transportation flows in Tehran metropolitan, the suburb to the suburb, the suburb to the central city (Tehran) and vice versa, Air pollution center Rise cannot be attributed to Tehran alone, as the area of pollutant sources has been distributed within the "Tehran metropolitan region ".So, the amount of spatial correlation between air pollution maps and transportation flow maps in selected days (2 Bahman 1392, 5 Bahman 1393 and Dec. 7, 1395), in all cases indicated high spatial relations (more than 75%), Confirmation the idea of this paper. Analysis of this situation in triple loops also shows that the highest volume of transportation is in the city of Tehran (CBD), suburban and exurban areas, respectively and the distribution pattern and spatial accumulation of pollution are also subject to this situation.
Dr Mohamad Zaheri, Mr Ali Majnouni-Toutakhane,
Volume 19, Issue 53 (6-2019)
Abstract
The increased use of thermal power plants has led to the spread of greenhouse gases in the air and has caused psychological problems for humans. Accordingly, the present study was conducted to measure the pollutants released by Sahand Bonab thermal power plant and to investigate the effects of this pollution on the psychological and psychological pressure of rural residents. The GWP100 method was used to measure the pollutants of the power plant and to measure the mental and emotional pressures of the citizens, a questionnaire was used to assess the psychological stress of Markham. The statistical population of this study is 10254 people over 15 years of age in 7 villages located in the greenhouse of the power plant. Using formulas and simple random sampling, 375 subjects were selected as sample size. The results showed that the most pollutants released are CO2 and NOx, which is 4.17 times the warm seasons in the seasons. Also, analysis of the results by using a Pearson test showed that six variables including neurological and disturbing variables p= 0.272, stress and psychological stress p= 0.325, feeling of energy decrease, p= 0.287, feeling of despair and disappointment in life p = 0.142, feeling Depression in life of p= 0.211 and change in behavior patterns in everyday life p= 0.269 had the most effect on air pollution. Also, mental and psychological stress in nearby villages was higher than in remote villages, more women than young men than older men and elderly people. The results of multivariate regression and path analysis showed that in general, the air pollution caused by the power plant has the ability to explain R2 = 37.42 percent of the changes related to the psychological and psychological pressure of the villagers. Finally, it can be said that thermal power plants have negative mental and psychological effects according to type of activity, type of age and gender of the villagers, which should be considered in the studies of the construction of power plants.
Mrs. Atefeh Shahmohammadi, Dr. Ali Bayat, Mr. Saeed Mashhadizadeh Maleki,
Volume 22, Issue 67 (12-2022)
Abstract
Air pollution is one of the major problems in large cities, which can be harmful to human health and the environment. Isfahan is one of the most polluted cities in Iran.
Its geographic location and low wind speed, industrial activities, transportation, agriculture, and other human activities have created critical air pollution conditions for the city. Nitrogen dioxide is an important pollutant of air pollution, which is monitored using ground stations and satellite measurements. In this paper, daily data of nitrogen dioxide from Ozone Monitoring Instrument (OMI) satellite sensor, wind and surface temperature of Isfahan Meteorological Station data were used between October 2004 and May 2016. The average amount of nitrogen dioxide in the measured range is .The highest amount of nitrogen dioxide ( ) was observed in December and the lowest ( ) was observed in July. The standard deviation of the winter season ( ) is higher than the summer season ( ). The correlation coefficient of nitrogen dioxide with wind and temperature was -0.41 and -0.54, respectively, which indicates the higher importance of temperature in nitrogen dioxide changes. After the formation of the time series, the average monthly nitrogen dioxide content was determined using spectral analysis of least squares of statistically meaningful peaks corresponding periods. These statistically meaningful peaks corresponding periods have been eliminated from the mean monthly nitrogen dioxide time series, and with the linear fit on the residual time series, the trend has been calculated. The nitrogen dioxide trend for Isfahan is per year with 95% confidence.
Hamed Ahmadzadeh, Ph.d Mahmoud Reza Keymanesh, Siavash Makani Bonab, Iman Ghanizadeh,
Volume 23, Issue 68 (3-2023)
Abstract
The rapid growth of metropolitan areas around the world, coupled with the increase in population in these cities, has created numerous problems such as traffic congestion and disruption to the inter-city transportation system. Therefore, this dilemma has been one of the major challenges facing urban planning in the late twentieth century which has influenced the achievement of sustainable urban development goals. Electronics in cyberspace are an integral part of life. Today, the use of public transport is one of the issues that are related to different aspects of quality of life. The purpose of this study was to investigate the impact of using public transport in reducing traffic and air pollution. In this study, library and field method were used for data collection. The statistical population of the study consisted of experts and urban planning experts. Sample size was estimated 25 people using snowball technique. In this study, AHP technique was used to achieve the research objectives. Data gathering tool was paired comparison questionnaire. The results of this study showed that the importance of indicators (criteria), in terms of their importance percentages are: Safety 0.499, Environmental Pollution 0.313, Cheapness 0.120 and Convenience 0.068 and finally the most preferred option between two motor modes, The public transport mode is identified at 0.778 compared to the 0.222 personal transport mode.
Mr Mohammadamir Moharreri, Kamran Lari, Foroozan Arkian, Gholamreza Salehi,
Volume 23, Issue 69 (6-2023)
Abstract
There are several limiting factors to the development of cities. These factors lead cities to develop in certain directions. Air pollution as a major problem of metropolises can itself be considered as a limiting factor of urban development by urban decision makers. 4 relatively large power plants are operating in Mashhad. There are currently two power plants in the east of the city and two in the west of Mashhad. Most of the fuel in these power plants is gasoline and natural gas. Modeling the air pollutant emissions of these power plants and identifying the pattern of pollutant emissions across the city can play a key role in the quality of life and health of approximately 3.5 million Mashhad residents. The outputs of this model can also be used as an effective parameter in estimating the urban development model. In this study, the emission of NOX, CO and 10PM pollutants was modeled and evaluated using AERMOD software in Mashhad. Using Arc GIS software, the population affected by these air pollutants was determined by one year solar time, the concentration of pollutants in different areas of the city and the area affected by the pollution concentration range was determined.
Shahrzad Amirsarvari, Mohammad Ebrahim Ramazani,
Volume 23, Issue 70 (9-2023)
Abstract
The creative city will make all your try and relying to the idea of people to solve their problems and build a city of people who are looking for their desired cities. The creative city is not only a space in which creativity grows, but organizing and managing it is creatively planned. The title and general purpose of this research is the assessment of the environmental capability of Tabriz city in the formation of a creative city , Tabriz is one of the main cities of the country and among the major centers of urbanization in Iran, which is the center of East Azerbaijan province and in comparison with the center of neighboring provinces in terms of quantitative (such as population) and Quality (such as functions) has a speed positions index and is far higher in the surface. Accordingly, in this thesis at first the theoretical foundations related to the subject has been expressed and the research method and data collection is a field and library. The statistical population of the research (using Morgan table) was 384 population of Tabriz, which was conducted through a stratified random sampling questionnaire. Validity and reliability of the questionnaire were determined by content validity and formal validity and calculating Cronbach's alpha confirmation. The results of the study showed that environmental power as well as social and social activities on the formation of creative city has a positive and significant effect on the formation of creative city. The results of this study show that tabriz city does not have the environmental power needed for the formation of creative city.
Dr Abolhassan Gheibi, Mr Ali Soleymani, Hossein Malakooti,
Volume 25, Issue 76 (3-2025)
Abstract
Nitrogen dioxide is a significant factor affecting air quality in various regions worldwide. The aim of this study is to examine the concentration and trends of nitrogen dioxide pollution between 2005 and 2018, and explore its association with precipitation levels in the region. Based on data derived from the OMI sensor in Iran, the average vertical column concentration of nitrogen dioxide during this period revealed that the highest concentration was observed in the troposphere. Megacities, particularly Tehran metropolis, exhibited elevated levels of nitrogen dioxide due to the high population density and extensive road transportation. Analyzing the annual changes in nitrogen dioxide concentration in the troposphere alongside the average annual precipitation in Iran, it was observed that the pollutant concentration increased from 2005 to 2016 and subsequently decreased from 2016 to 2018, primarily due to population growth. However, when considering the overall trend, there was an upward trend with a slope of 3.53× -2. In contrast, the time series analysis of average annual precipitation in Iran demonstrated a declining trend with a slope of (-0.159 mm × ). Comparing the trends of these two variables, it can be deduced that they exhibit a negative correlation.
