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Land use regression models for Alkylbenzenes in a middle eastern megacity: Tehran study of exposure prediction for environmental health research (tehran sepehr)
, Article Environmental Science and Technology ; Volume 51, Issue 15 , 2017 , Pages 8481-8490 ; 0013936X (ISSN) ; Schindler, C ; Hosseini, V ; Yunesian, M ; Künzli, N ; Sharif University of Technology
American Chemical Society
2017
Abstract
Land use regression (LUR) has not been applied thus far to ambient alkylbenzenes in highly polluted megacities. We advanced LUR models for benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX using measurement based estimates of annual means at 179 sites in Tehran megacity, Iran. Overall, 520 predictors were evaluated, such as The Weather Research and Forecasting Model meteorology predictions, emission inventory, and several new others. The final models with R2 values ranging from 0.64 for p-xylene to 0.70 for benzene were mainly driven by traffic-related variables but the proximity to sewage treatment plants was present in all models indicating a major local...
Modeling of Ground-Level Ozone Concentrations in Tehran using CMAQ Model
, M.Sc. Thesis Sharif University of Technology ; Arhami, Mohammad (Supervisor)
Abstract
Every year, air pollution is causing immense harm to humans and the environment. To cause Air pollution, several factors are involved. Among these are the sources of emissions such as factories, power plants and Cars, meteorological factors such as temperature and wind speed and geographical conditions such as altitude, postal and looming around the area, land slope and soil type region. The aim of this study is to identify factors that affect the ozone concentration in Tehran, which could help identifying other secondary pollutants. For this purpose, a combination tailored to the geography of Tehran using CMAQ-WRF-SMOKE-made programs. This model includes four intervals each of which lasting...
Theoretical-experimental investigation of Co emission from an oil refinery incinerator
, Article American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM ; Vol. 1C, issue , 2014 ; Abrar, B ; Yazdi, M. K ; Zeinali, M ; Schneider, G. E ; Sharif University of Technology
Abstract
In this paper, we investigate the CO emission from an oil refinery gas incinerator both theoretically and experimentally. At the beginning of this research, our collected data from this incinerator showed that the CO contamination would be far exceeding the permissible environmental standards at the stack exhaust. Therefore, we decided to perform a combined theoretical-experimental study to find a reasonable solution to reduce the CO pollution suitably. Our theoretical study showed that a reliable solution would be to increase the incinerator operating temperature. However, we needed to collect some data from this incinerator to examine if our achieved analytical solution would work...
The air quality of Tehran underground railway transit system
, Article BHR Group - 14th International Symposium on Aerodynamics and Ventilation of Tunnels, 11 May 2011 through 13 May 2011 ; May , 2011 , Pages 551-561 ; 9781855981232 (ISBN) ; Abbasspour, M ; Mansoori, N ; Moattar, F ; Nouri, N ; Allahyari, M ; Sharif University of Technology
2011
Abstract
This study examines the air quality on line 1 and 2 of Tehran underground metro. The total suspended particulate (TSP), PM10, PM2.5, PM1, CO2, NO, NO2, SO2, relative humidity and air temperature were measured. An integrated air quality index was also calculated for each location. The results revealed that, PMlO, PM2.5, and SO2 concentrations are higher than their environmental standard levels. The in station CO2 levels are higher while its' in train levels are lower than environmental permissible level. The air quality index showed that the in-train air quality is more acceptable than the instation air quality
Optimisation of micro gas turbine by exergy, economic and environmental (3E) analysis
, Article International Journal of Exergy ; Volume 7, Issue 1 , 2010 , Pages 1-19 ; 17428297 (ISSN) ; Ahmadi, A ; Ehyaei, M. A ; Sharif University of Technology
2010
Abstract
This research proposes a new method for optimisation of a power generation system based on exergy fuel cost and external social cost of air pollution. A thermodynamic model is provided to estimate the outlet mass flow rates of CO2, CO, NO and NO2 for a gas turbine based on maximising the first and second law efficiencies and minimising the objective function. Results show that inclusion of the external social cost of air pollution increases the optimum excess air ratio if temperature constraint due to metallurgical consideration is disregarded. Otherwise external social cost of air pollution is independent of optimised conditions
Ozone concentration forecasting with neuro-fuzzy approaches
, Article ICSCCW 2009 - 5th International Conference on Soft Computing, Computing with Words and Perceptions in System Analysis, Decision and Control, 2 September 2009 through 4 September 2009, Famagusta ; 2009 ; 9781424434282 (ISBN) ; Mahjoob, M. J ; Zarringhalam, R ; Miranian, A ; Sharif University of Technology
Abstract
Forecasting is a challenging problem in highly nonlinear dynamic systems. The main goal in development of forecasting models in complex systems is to produce a model that can accurately behave similar to the main system. In problems such as air pollution forecasting, the presence of uncertainties and nonlinearities affects the model's precision. In this paper, ozone concentration, which is well-known as an index for air pollution is forecasted using neuro-fuzzy models. Causal variables are integrated in the models in order to enhance the model's performance. The results are compared to a fuzzy logic approach to demonstrate reliability and accuracy of the proposed model using real observed...
Intelligent transportation system for respiratory patients
, Article International Conference on Control, Automation and Systems, ICCAS 2007, Seoul, 17 October 2007 through 20 October 2007 ; December , 2007 , Pages 1430-1433 ; 8995003871 (ISBN); 9788995003879 (ISBN) ; Shirali Shahreza, M ; Sharif University of Technology
2007
Abstract
ITS (Intelligent Transportation System) can be applied to many fields. In this paper we present an ITS system for respiratory patients based on finding cleaner paths. In this system the information related to air pollution of different sections of the city is received from center of air-pollution information presentation and a path with least degree of air pollution is suggested. Therefore respiratory and cardiac patients can commute with fewer difficulties. In our project this system has been simulated manually. ©ICROS
The application of MODIS satellite remote sensing in estimation of particulate urban air pollution
, Article 100th Annual Conference and Exhibition of the Air and Waste Management Association 2007, ACE 2007, 26 June 2007 through 29 June 2007 ; Volume 2 , 2007 , Pages 736-742 ; 9781604238464 (ISBN) ; Amid, F ; Keshavarzi, H ; Sharif University of Technology
Air and Waste Management Association
2007
Abstract
Particulate matter (PM) pollution is a growing concern in urban areas in the developing countries because of its potential to aggravate cardiovascular and respiratory illnesses. Traditional approaches in monitoring urban pollutants have relied on ground-based networks even though they essentially provide point measurements and are inadequate for health alerts on large spatial and long temporal scales. Recent advances in satellite imagery has attracted managers to look into this new alternative as a predictive tool for improving air quality at urban and regional scales by providing necessary data in advance of the onset of actual severe conditions. Moderate Resolution Imaging...
A novel viewpoint to the green city concept based on vegetation area changes and contributions to healthy days: a case study of Mashhad, Iran
, Article Environmental Science and Pollution Research ; Volume 29, Issue 1 , 2022 , Pages 702-710 ; 09441344 (ISSN) ; Makian, M ; Gheibi, M ; Fathollahi Fard, A. M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
One of the significant challenges in urbanization is the air pollution. This highlights the need of the green city concept with reconsideration of houses, factories, and traffic in a green viewpoint. The literature review confirms that this reconsideration for green space has a positive effect on the air quality of large cities and to reduce the air pollution. The purpose of this study is to evaluate the annual vegetation changes in the green space of Mashhad, Iran as a very populated city in the middle east to study the air pollution. To investigate the relationship between the air pollution and vegetation, the Landsat 8 satellite images for summer seasons of 2013–2019 were used to extract...
The effect of source motion on contaminant distribution in the cleanrooms
, Article Energy and Buildings ; Volume 43, Issue 4 , April , 2011 , Pages 966-970 ; 03787788 (ISSN) ; Sajadi, B ; Molaeimanesh, G. R ; Sharif University of Technology
2011
Abstract
In the recent decades, cleanrooms have found growing applications in broad range of industries such as pharmacy and microelectronics. Concerns about negative effects of the contaminant exposure on the human health and product quality motivate many researchers towards understanding of the airflow and contaminant distribution though these environments. With an improvement in computational capacity of the computers, computational fluid dynamics (CFD) technique has become a powerful tool to study the engineering problems including indoor air quality (IAQ). In this research, indoor airflow in a full-scale cleanroom is investigated numerically using Eulerian-Eulerian approach. To evaluate the...
Spatiotemporal description of BTEX volatile organic compounds in a middle eastern megacity: tehran study of exposure prediction for environmental health research (Tehran SEPEHR)
, Article Environmental Pollution ; Volume 226 , 2017 , Pages 219-229 ; 02697491 (ISSN) ; Hosseini, V ; Schindler, C ; Hassankhany, H ; Yunesian, M ; Henderson, S. B ; Künzli, N ; Sharif University of Technology
Abstract
The spatiotemporal variability of ambient volatile organic compounds (VOCs) in Tehran, Iran, is not well understood. Here we present the design, methods, and results of the Tehran Study of Exposure Prediction for Environmental Health Research (Tehran SEPEHR) on ambient concentrations of benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX. To date, this is the largest study of its kind in a low- and middle-income country and one of the largest globally. We measured BTEX concentrations at five reference sites and 174 distributed sites identified by a cluster analytic method. Samples were taken over 25 consecutive 2-weeks at five reference sites (to be used for...
Determination of Traffic Generated Particle Distribution using Air Pollution Dispersion Models and Investigating Effectiveness of Mitigating Solutions: Case study, City of Tehran
, M.Sc. Thesis Sharif University of Technology ; Shamloo, Amir (Supervisor) ; Hosseini, Vahid (Co-Advisor)
Abstract
In this study, in the base case using a modeling system WRF=CAMx Distribution concentration of all pollutants from mobile sources in an episode of 60 days (November and December 2015) is calculated in Tehran. In this context, the emissions inventory related to mobile sources outputs the code in Fortran and WRF meteorological model to model air quality prepared and then using the CAMx, Tehran’s air quality is simulated. In order to verification in this case, the results of pollutant concentration NO2, CO, PM2٫5, with concentrations of air pollution monitoring stations compared. Given that in this study the concentration of pollutants from mobile sources is modeled, predicted by the model,...
Investigation the Effects of Inversion on Tehran Air Quality Using Meteorological and Photochemical Models during Normal and High Concentrations Episodes
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor) ; Rashidi, Yousef (Co-Advisor)
Abstract
In this study, The Comprehensive Air Quality Model with extensions (CAMx model, v5.41), was used to model gas phase pollutants over Tehran modeling domain during two episodes of July 7th to July 13th and November 30th to December 6th, 2012. In the second episode due to very high concentration of pollutants caused by a combination of meteorological conditions and occurrence of an inversion, a forced holiday was imposed on the city-wide operations to protect the health of citizens. It was found that WRF/CAMx modeling system is a useful tool for the analysis of urban environmental problems and predicting critical conditions. The WRF simulation results for 2-m height temperature, 10-m height...
Development and Application of Mobile Source Emission Factor Matrix for Use in Wrf/Camx Air Dispersion Model of Tehran
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
Tehran, with approximately 750 km2 of land area, a population of more than 8 million people with about 4 million active on-road vehicles, is dealing with serious air pollution problems. To model the environmental phenomenon precisely, this study aims to develop on-road air pollutant emission factor matrices based on existing traffic in Tehran routes and to run air quality modelling within Tehran geographic boundaries. We developed emission factor matrices using SMOKES-MOVES emission modeling system. To do so, we calculated on-road emission factors from actual traffic-related data and run MOVES emission model. And use use them for different pollutants considered in air quality models. Then,...
Modeling Effects of Regional Windblown Dust on Particulate Matter Concentration of Tehran using CMAQ
, M.Sc. Thesis Sharif University of Technology ; Arhami, Mohammad (Supervisor)
Abstract
In recent years, dust storms have turned into one of the most prominence environmental issues, existing in Tehran. The infiltration of dust through west borders has led to significant increase in the concentration of Tehran’s pollutants. The main abroad source of these dusts are deserts located in Middle East. The contribution of Middle East deserts in daily concentration of PM10, without the inclusion of local emission sources, was analyzed in previous studies. In this study, we analyzed the contribution of dust storms, formed in Middle East, in Tehran’s PM10 and PM2.5 concentration, using CMAQ model. Dust periods between 2012 and 2014, was identified using observation data and satellite...
Impacts of Urban Design on Air Pollution Case Study of Tehran
, Ph.D. Dissertation Sharif University of Technology ; Arhami, Mohammad (Supervisor)
Abstract
This study aims to investigate the effects of urban design and development on Tehran's air quality in calm conditions. Known strategies such as bright roofs and facades, urban development, and modification of the building density are in the focus. The WRF model coupled with Single-Layer Urban Canopy and Building Effects Parametrization canopy schemes were used to predict weather parameters. SMOKE and CMAQ models computed the concentration of pollutants in the city. Urban canopy schemes had correlation coefficients and an index of accordance of about 0.9 and the mean bias was lower than 2. Wind prediction had a lower correlation. The BEP scheme reduced the mean bias for temperature and...
Overview on the separation and removal of Haloaceticacid'S in drinking water
, Article 4th WSEAS International Conference on Waste Management, Water Pollution, Air Pollution, Indoor Climate, WWAI '10, 3 May 2010 through 6 May 2010, Sousse ; 2010 , Pages 25-31 ; 9789604741908 (ISBN) ; Soltanieh, M ; Mosavi, M ; Sharif University of Technology
2010
Abstract
The increase of pollution and the expansion of industrial, agricultural wastewater and urban runoff discharges in water sources have intensified the concentration of water pollutants. Considering that in Iran as in other countries the major part of drinking water is obtained from surface waters and due to the importance of disinfection, chlorination is doubtlessly the optimum and most common water treatment method used. However this method produces chlorination by-products (CBPs). Trihalomethanes(THMs) and Haloaceticacids (HAAs) are the main and most important groups of disinfection by-products (DBPs). Separation of THMs has gained a lot of breakthroughs since a lot of time elapses from its...
A numerical study of reactive pollutant dispersion in street canyons with green roofs
, Article Building Simulation ; Volume 11, Issue 1 , February , 2018 , Pages 125-138 ; 19963599 (ISSN) ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Tsinghua University Press
2018
Abstract
Roof greening is a new technique for improvement of outdoor thermal environment which influences air quality through its impacts on thermal and flow field. In order to examine effects of green roofs on reactive pollutant dispersion within urban street canyons, a computational fluid dynamics (CFD) model was employed which contained NO-NO2-O3 photochemistry and energy balance models. Simulations were performed for street canyons with different aspect ratios (H/W) of 0.5, 1.0, and 2.0 such that leaf area density (LAD) of green roofs changed. It was found that roof greening led distribution of pollutants to alter for H/W = 0.5 and 1.0 cases in such a manner that their averaged concentrations had...
Design of a mathematical model to minimize air pollution caused by job trips in Mega Cities
, Article Scientia Iranica ; Volume 16, Issue 2 B , 2009 , Pages 177-188 ; 10263098 (ISSN) ; Dana, T ; Shafiepour, M ; Mahmoudi, M ; Sharif University of Technology
2009
Abstract
Urban transportation is one of the main sources of air pollution in mega cities, and urban job related trips can effectively influence the state of air quality. Tehran, the capital of Iran, with a population of 7.3 million, was selected for this study. The present model is designed to investigate the effect on traffic of the business working hours of different occupations and, as a result, on the status of air pollution. Daily job, non-job and recreational trips using the present vehicle fleet is a major factor affecting air pollution in Tehran. In the context of the present study, the necessary information was utilized to define some relations between job trips and pollutant emissions. The...
Nonlinear robust control of air handling units to improve the indoor air quality & CO2 concentration: A comparison between H∞ & decoupled sliding mode controls
, Article Applied Thermal Engineering ; Volume 160 , 2019 ; 13594311 (ISSN) ; Moradi, H ; Alasty, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Air-handling units (AHUs) are the installations responsible for the control of temperature and humidity inside a space using the heating, cooling, humidifier and drying air components. In this research, a multivariable nonlinear dynamic model of the AHU with one zone in the VAV (variable air volume) system for working in the summer is considered. The indoor temperature, relative humidity and carbon dioxide concentration are controlled via manipulation of the valve positions of the air flow rate, cold water flow rate and fresh air percent. Due to the complexity and nonlinearity of AHU model and also the existence of various operating points and uncertainty, model uncertainties are included....