Estimating ground-level PM2.5 concentrations by developing and optimizing machine learning and statistical models using 3 km MODIS AODs: case study of Tehran, Iran

, Article Journal of Environmental Health Science and Engineering ; Volume 19, Issue 1 , 2021 ; 2052336X (ISSN) Sotoudeheian, S ; Arhami, M ; Sharif University of Technology

Springer Science and Business Media Deutschland GmbH 2021

Abstract

Purpose: In this study we aimed to develop an optimized prediction model to estimate a fine-resolution grid of ground-level PM2.5 levels over Tehran. Using remote sensing data to obtain fine-resolution grids of particulate levels in highly polluted environments in areas such as Middle East with the abundance of brightly reflecting deserts is challenging. Methods: Different prediction models implementing 3 km AOD products from the MODIS collection 6 and various effective parameters were used to obtain a reliable model to estimate ground-level PM2.5 concentrations. In this regards, the linear mixed effect model (LME), multi-variable linear regression model (MLR), Gaussian process model (GPM),...

Investigating the Relationship Between Measured Parameters by Satellite and Ground-Level Concentrations of PM

, M.Sc. Thesis Sharif University of Technology Sotoudeheian, Saeed (Author) ; Arhami, Mohammad (Supervisor)

Abstract

Obtaining particulate matter (PM) concentration is very important in epidemiological studies. Measurement at the ground levels has been used as an accurate method to obtain PM levels. However, these measurements are more indicative of a small area around the stations than a whole region. Usually, limited space coverage and irregular distribution of air quality stations at the ground level is a restriction in the studies of air pollution and its effect on human health and environment. In this regard satellite measurements have been used for indirect estimation of PM concentration at ground levels. However, the correlation between satellite measurements and ground based data is affected by...

Developing Models to Estimate Ground Level PM2.5 Concentrations Using Satellite Measurements

, Ph.D. Dissertation Sharif University of Technology Sotoudeheian, Saeed (Author) ; Arhami, Mohammad (Supervisor)

Abstract

In this study different prediction models including linear mixed effect (LME), multi-variable linear regression (MLR), gaussian process model (GPM), artificial neural network (ANN) and support vector regression (SVR) were developed using satellite AOD product - with spatial resolution of 3 km – coupled with various auxiliary parameters to estimate ground-level PM2.5 over Tehran. The influence of site effect term on performance of LME models was evaluated using random intercept for monitoring sites. Results showed LME models without this term were able to explain variabilities of PM2.5 in ranges of 60 – 66% and 35 – 41% during model fitting and cross-validation (CV), respectively. By...

Impact of middle eastern dust sources on PM10 in iran: highlighting the impact of tigris-euphrates basin sources and lake urmia desiccation

, Article Journal of Geophysical Research: Atmospheres ; Volume 121, Issue 23 , 2016 , Pages 14,018-14,034 ; 2169897X (ISSN) Sotoudeheian, S ; Salim, R ; Arhami, M ; Sharif University of Technology

Blackwell Publishing Ltd 2016

Abstract

Contribution of different Middle Eastern dust origins to PM10 (PM with aerodynamic diameters less than 10 µm) levels in several receptor large cities in Iran was investigated. Initially, the major regional dust episodes were determined through statistical analysis of recorded PM levels at air quality stations and verified using satellite images. The particles dispersion was simulated by Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) to regenerate PM10 during the dust episodes. The accuracy of the modeled results was rather convincing, with an average squared correlation coefficient (R2) of 0.7 (max = 0.95). Consequently, the contributions of different dust sources to the...

Using high-resolution climate models to identify climate change hotspots in the middle east: A case study of iran

, Article Climate ; Volume 10, Issue 11 , 2022 ; 22251154 (ISSN) Sotoudeheian, S ; Jalilvand, E ; Kermanshah, A ; Sharif University of Technology

MDPI 2022

Abstract

The adverse effects of climate change will impact all regions around the world, especially Middle Eastern countries, which have prioritized economic growth over environmental protection. However, these impacts are not evenly distributed spatially, and some locations, namely climate change hotspots, will suffer more from climate change consequences. In this study, we identified climate change hotspots over Iran—a developing country in the Middle East that is facing dire economic situations—in order to suggest pragmatic solutions for vulnerable regions. We used a statistical index as a representative of the differences in climatic parameters for the RCP8.5 and RCP4.5 forcing pathways between...

Effect of empty bed residence time on biotrickling filter performance: Case study-triethylamine

, Article International Journal of Environmental Science and Technology ; Vol. 11, issue. 1 , 2014 , pp. 183-190 ; ISSN: 17351472 Mirmohammadi, M ; Bayat, R ; Keshavarzi Shirazi, H ; Sotoudeheian, S ; Sharif University of Technology

2014

Abstract

In this study, a laboratory-scale biotrickling filter (BTF) is used to remove Triethylamine (TEA) from gaseous wastes. The BTF is made of stainless steel with a height of 210 cm and an internal diameter of 21 cm packed with lava rocks. TEA elimination pattern was evaluated by changing empty bed residence times (EBRTs). The maximum elimination capacity (EC) has been determined to be 87 g/m3/h. At all EBRTs 52, 31, 20, and 10 s, contaminant transferring from gas phase to liquid was more than the EC. Also, the removal efficiency was 100 % for a mass loading of 100 g/m3/h. While the liquid recirculation velocity of 3.466 m3/m2/h was maintained, the flow rate was adjusted to 60, 100, 156, and 312...

Performance of three-level spectrally encoded spreadtime CDMA in the presence of multiple interferences [electronic resource]

, Article IET Communications ; July 2011, Volume 5, Issue 10, P. 1328-1335 Mashhadi, S. (Saeed) ; Mashhadi, Saeed ; Salehi, J. A ; Sharif University of Technology

Abstract

In this study the authors present an in-depth study, analysis and discussion on maximum likelihood (ML)-based receiver for a typical spectrally encoded spread-time CDMA in the presence of multiple narrowband interference (NBI) signals in an additive white Gaussian noise channel. Furthermore, the authors demonstrate that by combining useful properties of ML-based receiver and three-level codes, that is, codes with values of -1, 0, +1, the authors can introduce a new strategy in which superior performance with respect to previous receiver structure based on two-level codes, that is, codes with values of -1, +1, can be attained. With the help of an example, the authors drive, first, the...

Investigation of Multiphase Flow in Oil Wells (with Focus on Two Phase Flow), Flow Pattern Recognition and Modeling

, M.Sc. Thesis Sharif University of Technology Shams, Reza (Author) ; Shad, Saeed (Supervisor) ; Jamshidi, Saeed (Supervisor)

Abstract

The concurrent flow of oil and water is a common occurrence in the field of multiphase flow in different fields including petroleum industry. In oil and gas, production engineers often face a situation in which more than one phase is flowing through the producers. In such conditions an accurate assessment of pressure loss inside the well plays a vital role in efficient and effective production planning. Changes in well orientation, wellbore diameter, reservoir and fluid properties as well as fluid flow rates are among parameters in which will affect the flow patterns that can occur inside a well during its life time. These flow patterns are created as a result of a competition between...

Casing Design Optimization Considering Drilling and Production Conditions

, M.Sc. Thesis Sharif University of Technology Sadeghi, Mahdi (Author) ; Jamshidi, Saeed (Supervisor) ; Shad, Saeed (Supervisor)

Abstract

Casing design is one of the most expensive parts in the drilling of oil wells, and any cost reduction with the basic design of these casing strings will significantly reduce the total cost of the operation. In recent years, occurring scenarios-based casing design has become popular; Because in many cases, it eliminates non-occurring scenarios such as gas kick and saves on drilling costs. In this study, we have tried to investigate all scenarios that may occur during the lifetime of the well, whether drilling or production, and for each well, based on its own field information, possible scenarios for each casing part are selected separately and the applying loads are calculated. For this...

PRI (Palm Rotation Indicator): a metric for postural stability in dynamic nonprehensile manipulation [electronic resource]

, Article Journal of MECHANIKA ; 2012, Vol. 18, No. 4, pp. 461-466 Beigzadeh, B. (Borhan) ; Meghdar, Ali ; Sohrabpour, Saeed ; Sharif University of Technology

Abstract

In this study, we discuss the postural stability of a nonprehensile manipulation problem, which deals with multibody objects. As a metric for postural stability, we define PRI. Then, the system is posturally stable, if PRI is inside the convex hull of the object-manipulator contact surface. We then discuss that dynamic biped locomotion is a special case of dynamic nonprehensile manipulation in all aspects; we prove that ZMP (zero-moment point) and FRI (zoot rotation indicator) are special cases of PRI (palm rotation indicator). Simulations and experiments corresponding to simple examples support the results

On the Domination Polynomial of Graphs

, M.Sc. Thesis Sharif University of Technology Ebrahimi, Zeinab (Author) ; Akbari, Saeed (Supervisor)

Some Applications of Combinatorial Nullstellensatz in Graph Theory and Combinatorics

, M.Sc. Thesis Sharif University of Technology Fakhari, Amin (Author) ; Akbari, Saeed (Supervisor)

Electrochemical Determination of Piroxicam at thin Carbon
Nanoparticle Composite And Investigation of the Electrochemical Behavior and Synthesis of Catechols in the Presence of Mercapto Methyl Tetrazol as a Nucleophile

, M.Sc. Thesis Sharif University of Technology Jokar, Effat (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

The electrochemical oxidation behavior of the anti-inflammatory drug piroxicam was investigated. A carbon nanoparticle (CNP)-chitosan (CS) film-coated graphite electrode (PGE) was fabricated and the electrochemical behaviors of piroxicam on its surface was investigated by the means of cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). In comparison to the bare PGE, at the surface of the CNP-CS film modified electrode, the oxidation peak current of piroxicam increased significantly and the peak potential shifted negatively. Consequently, a simple and sensitive electroanalytical method was developed for the determination of piroxicam. The...

Chemically Modified Electrodes Based on Conducting Polymers and Carbon Nanotubes: Application to Voltammetric Determination of Some Biological and Pharmaceutical Compounds

, M.Sc. Thesis Sharif University of Technology Asadian, Elham (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

There are high attractions in the development of conducting polymer (CP) coatings to improve the electrochemical properties and biocompatibility of electrodes in the area of biosensors. In the first part of this thesis, a new type of modified electrodes, constructing multi-walled carbon nanotubes (MWCNTs) and polypyrrole is prepared in a layer-by-layer process. In this procedure, the glassy carbon electrode is casted first by a drop suspension of MWCNTs, leading to formation a thin film on its surface. In the second step, electrochemical polymerization of pyrrole in the presence of tiron (used as doping anion) is performed on the surface of the MWCNTs pre-coated electrode. The modification...

Probing the Electrochemical Properties of Gold Electrode Modified with Edge-Functionalized Graphene and its Application

, M.Sc. Thesis Sharif University of Technology Aghajani, Talin (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

In the present work, edge-functionalaized graphene was used as electrode material and its electrochemical properties were systematically characterized by electrochemical impedance spectroscopy and cyclic voltammetry. Two methods were applied to modify the gold electrode surface. First method was the self assembling process of graphene nanosheets on gold electrode surface. Second method was simply casting specific amounts of graphene suspension on the gold electrode surface. Nyquist plots show decrease of the charge transfer resistance on the electrode surface at both cases. In cyclic voltammetry studies, first electrode shows no significant changes while the second electrode exhibits...

Probabilistic Methods in Graph Coloring

, M.Sc. Thesis Sharif University of Technology Ahadi, Arash (Author) ; Akbari, Saeed (Supervisor)

Abstract

Graph Theory and Combinatorial Analysis like the other branches of science use the probability for solving their problems. At the first , we will introduce the most common tools from probability used in Discrete Mathematics, such as “The Lovasz Local Lemma”. Most of them are based on Linearity of Expectation, Concentration Theorems and some other innovative methods such as Deletation Method. We will present different examples for these techniques. Also we will introduce “Random Graphs” and their importance. Specially we will explain how to use “Threshold Functions” to obtain different properties about the majority of graphs. Rainbow Connection, is a natural and interesting quantifiable way...

Electrochemical Determination of Tyrosine and Tryptophan at the Surface of Pyrolytic Graphite Electrode Modified with Multi-Walled Carbon Nanotubes, New Coccine and Nitrazine

, M.Sc. Thesis Sharif University of Technology Ebrahimi, Shiva (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

At the first part of this thesis, a pyrolitic graphite electrode (PGE) modified with new coccine/multi-walled carbon nanotubes film (NC/MWCNT) was applied as a sensitive electrochemical sensor for determination and study of electrochemical behavior of tyrosine (Tyr) in aqueous solutions. The results showed that NC/MWCNT caused a remarkable increase in the peak current so the NC/MWCNT/PGE electrode surface was far more sensitive to the concentration of Tyr than the PGE surface. The determination of Tyr was investigated by linear sweep voltammetry (LSV). Experimental parameters, such as scan rate, pH and amount of the modifier used on the PGE surface were optimized by monitoring the LSV...

The Regular Graph Retated to Rings

, M.Sc. Thesis Sharif University of Technology Jamaali, Mohsen (Author) ; Akbari, Saeed (Supervisor)

Abstract

There are many papers in which some graphs are assigned to algebraic structures such as rings groupsThe concept of regular graph related to a ring was rst investigated by DF Anderson and A Badawi in Assume that R is a commutative ring and Z??R denotes the set of zerodivisors of R and Reg??R R n Z??R The regular graph of R which is denoted by Reg????R is a graph whose vertex set is Reg??R and two vertices x and y are adjacent if and only if x y ?? Z??R This can be generalized to a non commutative ring For the vertex set we consider the set of left ??right zerodivisors and join two elements if their sum is a left ??right zerodivisor Let R be the ring of n n matrices over a eld F with...

Zero-sum Flows in Graphs

, M.Sc. Thesis Sharif University of Technology Nategh, Emisa (Author) ; Akbari, Saeed (Supervisor)

Abstract

For an undirected graph G, a zero-sum flow is an assignment of non-zero real numbers on the edges of G such that the total sum of all edges incident with any vertex of G is zero. A zero-sum k-flow for a graph G is a zero-sum flow with labels from the set {±1, . . . , ±(k ? 1)}. In this thesis for a graph G, a necessary and sufficient condition forthe existence of zero-sum flow is given. It has been conjectured that if a graph G has azero-sumflow, then it has a zero-sum 6-flow. Also, it has been proved that this conjectureand Bouchet’s Conjecture for bidirected graphs are equivalent. It is shown that the con-jecture is true for 2-edge connected bipartite graphs, and every r-regular graph...

Application of Pore Network Modeling in Study of Rock Typing Algorithms

, M.Sc. Thesis Sharif University of Technology Sistan, Morteza (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

One of the most important issues in modeling and simulation of reservoirs is determination of different rock types or Rock Typing. In this study, after a brief review of some conventional methods for rock typing, their capabilities have been investigated. In this way, for the first time, pore network modeling is used as a tool for validating the rock typing methods. By using flow simulation in porous medium with pore network modeling approach, similar rock types data have been generated and these artificially data have been used for validating of rock typing methods. To form more realistic pore networks, both regular and irregular pore network have been modeled and analyzed. Pore size...