An investigation into the effects of green space on air quality of an urban area using CFD modeling

, Article Urban Climate ; Volume 34 , December , 2020 Moradpour, M ; Hosseini, V ; Sharif University of Technology

Elsevier B.V 2020

Abstract

Tehran, the capital of Iran, is one of the most polluted cities in the Middle East. However, there is no clear evidence of the effects of Tehran green spaces on reducing air pollution because there are still challenges to application of vegetation for improving air quality. The current study investigates the effects of a large volume of green space with 275 ha area in the vicinity of major highways on nearby air quality. Similar environments are often seen in many cities around the world. A computational fluid dynamics model containing aerodynamics and deposition effects of vegetation was used to simulate pollutant dispersion for eight wind directions and three different foliage densities....

Modeling of Urban Air Pollutants Dispersion

, M.Sc. Thesis Sharif University of Technology Moradpour, Mrayam (Author) ; Farhanieh, Bijan (Supervisor)

Abstract

Air pollution is lateral and inappropriate product of industry and technology development that grows along them, unfortunately. Now its domain extended from local and national issues to global issues. For years like other branches of environmental sciences and other scientific fields, scientists apply formulas and mathematical equations. Nowadays, air pollution modeling is fundamental and powerful tool for air pollution studies, especially in prediction of air pollution conditions, pollutants emission and their concentration under different conditions and arbitrary locations. In this research, numerical modeling of urban air pollutants dispersion is discussed. After validation of results,...

Air Pollution Dispersion Study in a Diverse Land-Use Urban Area Using Numerical Simulation

, Ph.D. Dissertation Sharif University of Technology Moradpour, Maryam (Author) ; Hosseini, Vahid (Supervisor)

Abstract

Air pollution modeling is a powerful and low-cost tool for taking appropriate strategies to control air pollution. In this research, the effects of vegetation on air pollutant dispersion were studied using computational fluid dynamics models. At the beginning, aerodynamics and thermal effects of vegetation on reactive pollutant dispersion including NO, NO2 and O3 under photochemistry cycle were investigated in two different geometries. In the first geometry, tree planting in an urban environment involving several canyons was simulated. Results show that tree planting causes flow reversal, temperature decrease, and concentration field change. Concentration change of each pollutant not only...

A numerical investigation of reactive air pollutant dispersion in urban street canyons with tree planting

, Article Atmospheric Pollution Research ; Volume 8, Issue 2 , 2017 , Pages 253-266 ; 13091042 (ISSN) Moradpour, M ; Afshin, H ; Farhanieh, B ; Sharif University of Technology

Elsevier B.V 2017

Abstract

Vegetation acts as a momentum and thermal sink, affecting the mixing of species and temperature-dependent constants of reaction rates. Numerical simulations were performed to investigate the effects of vegetation on the dispersion of reactive pollutants using a computational fluid dynamic (CFD) model coupled with NO-NO2-O3 photochemistry. Moreover, characteristics of temperature and flow fields were analyzed for different aspect ratios and leaf area densities. The results showed that flow is reversed in the presence of trees, and it enhances as leaf area density (LAD) increases; additionally, vegetation creates downward and vortex flows. The results also revealed that the dispersion of...

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) Moradpour, M ; 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...

Kinetics Investigation of Oxygen Evolution from Water Oxidation in the Presence of Bismuth Vanadate Nanocatalysts

, M.Sc. Thesis Sharif University of Technology Moradpour, Amin (Author) ; Rahman Setayesh, Shahrbanoo (Supervisor)

Abstract

In this project, BiVO4 , Mn3O4 and BiVO4- Mn3O4 nanocatalysts were synthesized using the hydrothermal method. The properties of these nanocatalysts were determined by XRD, SEM, FT-IR, DRS, PL, ICP, EDX, BET and AA techniques. Analysys XRD patterns and SEM images of samples confirmed monoclinic structure for BiVO4 and tetragonal structure for Mn3O4. The DRS and PL spectra showed adctrease in the band gap and electron – hole pair recombination for BM 60:40 relative to BiVO4. Oxygen production was studied in the presence of different percentages of BiVO4 and Mn3O4 in BiVO4 - Mn3O4 nanocomposite and was observed that the 60:40 wt.% (Bismuth vanadate 60% and manganese oxide 40%) produced more...

3d Design of a Microfluidic Chip for Anticancer Drugs Screening

, M.Sc. Thesis Sharif University of Technology Hashemi, Maryam Sadat (Author) ; Mashayekhan, Shohreh (Supervisor) ; Saadatmand, Maryam (Supervisor)

Abstract

Nowadays, advanced and inexpensive pre-clinical methods for investigating the effects of anti-cancer drugs are expanding. One of the latest three-dimensional laboratory modeling for evaluating the effects of drugs is the use of tumor-on-chip technology, which actually models the physiological system of the body through three-dimensional scaffolds, multicellular cultures, and shaped vascular systems. In this study, three-dimensional culture of cancer cells was performed in the form of spheroids. A chip of U-shaped microstructures with and without gaps was used to trap cells and form cancer spheroids. We simulated the simultaneous effect of drug and oxygen concentration distribution inside the...

Investigation the Effect of Conductive Scaffolds on Regeneration of the Heart Tissue

, M.Sc. Thesis Sharif University of Technology Moradpour, Kayvan (Author) ; Vossoughi, Manoochehr (Supervisor) ; Ahmadi Tafti, Hossein (Supervisor)

Abstract

Cardiovascular diseases, especially coronary artery disease and coronary heart disease, are the leading cause of death in human communities. After myocardial infarction, known as heart attack, the flow of oxygen to the heart muscle cells is disrupted. It causes the death of cells that leads to structural and functional changes in the heart muscle. Therefore, specialists try to find a way to repair and regenerate the heart muscle after myocardial infarction. Tissue engineering is used to develop substantial alternatives to assist clinical therapies. Recent studies have focused on the construction of scaffolds with various advanced techniques to create guiding channels that mimic the natural...

Investigation of Asphaltene Electro-deposition In Presence of Addetives

, M.Sc. Thesis Sharif University of Technology Moradpour, Nikoo (Author) ; Ayatollahi, Shahabodin (Supervisor) ; Dehghani, Farzaneh ($item.subfieldsMap.e)

Abstract

Given the decreasing trend of light petroleum reserves and the necessity to produce heavy and extra-heavy oil resources, the challenge of dealing with existing asphaltene related problems, which is the heaviest and the most complex component of crude oil, has become increasingly tangible. Asphaltene precipitates and deposits due to pressure, temperature or composition alterations which leads to obstruction of porous media and production facilities. Set the costly methods aside, one of the available approaches to prevent asphaltene precipitation, is to apply an electric field upon the suspected zone, which is cheap and uncomplicated. Besides, utilizing nano-particles while applying electric...

Model Checking of Stochastic Activity Networks

, M.Sc. Thesis Sharif University of Technology Maryam Bagheri (Author) ; Movaghar, Ali (Supervisor)

Abstract

Modeling and performance evaluation of the real time distributed systems is a significant problem. Stochastic activity network is one of the high level models used for this purpose. This network is an extension of generalized stochastic Petri net which is more powerful and flexible than other Petri net extensions. Checking the satisfiability of properties such as performance, dependability and user's expected properties is considerable in these models. Thus, using the approaches and generating modeling and model checking tools with the mentioned purpose is attractive. A model checker automatically checks the correctness of the system behaviors as properties against the model by getting the...

Robust Estimation and Control of a Planet Lander

, M.Sc. Thesis Sharif University of Technology Ahmadvand, Reza (Author) ; Kiani, Maryam (Supervisor)

Abstract

This study has focused on the important problem of landing on a planet as an important current and future space mission. In this regard, dynamics modeling and integrated state estimation and control problems have been investigated in different views. To this aim, first a novel concurrent representation for translational and rotational kinematics has been developed based on the extension of modified Rodrigues parameters to dual space. This parameter set, called dual modified Rodrigues parameters (DMRP), is then utilized to establish an integrated roto-translational dynamic. The proposed DMRP-based kinematics and dynamics have been verified via comparison to traditional methods of...

Optimal Energy Trading in a Smart Grid Based on Extremum-seeking Algorithm

, M.Sc. Thesis Sharif University of Technology Asgari, Houman (Author) ; Babazadeh, Maryam (Supervisor)

Abstract

Prevalent deployment of Distributed Energy Resources(DERs) in the demand side of electrical energy grids has several advantages such as greenhouse gases emission reduction, mitigation of power losses in the distribution grids and abatement of the dependency on the wholesale generation companies. At the same time, it paves the way for the advent of local interactive energy trading frameworks. In the following thesis, a distributed data-driven algorithm is developed for market-clearing in a community-based local energy market. The social welfare maximization is considered as the objective of the energy trading. The production and demand of electricity are the decision variables of sellers and...

Design of Microfluidic Chip for 3D Cell Culture

, M.Sc. Thesis Sharif University of Technology Ghobadi, Faezeh (Author) ; Saadatmand, Maryam (Supervisor)

Abstract

Understanding biological systems requires extensive knowledge of individual parameters, and to study the processes of cell differentiation and cell behavior, a suitable environment must be created with the physiological conditions of the human body. For this purpose, with the knowledge of microfluidics, a microenvironment can be provided to study the behavior of cells on a small scale. The use of bone tissue model microfluidic chips is an alternative and new method in which it is possible to study the behavior of cells to differentiate into bone and to examine the toxicity of drugs, which in itself can help in the effective and successful treatment of these cases show. Therefore, in this...

Navigation and Control of a Free-Flying Satellite for Cargo Transportation and Placement in Intra-Vehicular Environment

, M.Sc. Thesis Sharif University of Technology Moosavi, Farzan (Author) ; Kiani, Maryam (Supervisor)

Abstract

The main topic of this research is the navigation and control of a free-flying satellite with a robot manipulator while transferring and placing cargo on a space station. After connecting the cargo module, astronauts and robots need to deliver the available loads to the desired modules in a space station. Capturing an object or cargo is a critical issue studied extensively so far. However, delivery and placing of the cargo at the target point have not been investigated yet, to the best of the author’s knowledge; hence, this is a primary motivation for conducting the proposed research. After capturing the payload, the position and attitude of the manipulator with respect to the station’s...

Fabrication the Hydrogel Microfibers Using Bioprinter with Application in Cardiovascular Model

, M.Sc. Thesis Sharif University of Technology Heidari, Faranak (Author) ; Saadatmand, Maryam (Supervisor)

Abstract

Cardiovascular disease (CVD) currently remains a considerable challenge for clinical treatments. CVDs account for N17.5 million deaths per year and will predictably increase to 23.6 million by 2030. The main purpose is to create human model systems to study the effect of disease mutations or drug treatment on the heart. In addition, engineered cardiac tissues are considered promising candidates to be transplanted to improve the function of diseased hearts. For engineered active tissues/organs, 3D bioprinting can fabricate complex tissue architecture with a spatiotemporal distribution of bioactive substances (cells, growth factors, and others) to better guide tissue regeneration. However,...

Utilizing Gaussian Processes to Learn Dynamics of Unknown Torques Acting on a Spacecraft

, M.Sc. Thesis Sharif University of Technology Baradaran, Behdad (Author) ; Kiani, Maryam (Supervisor)

Abstract

Accurate and fast attitude estimation of a rigid body plays an essential role in the performance of a vehicle’s control system, especially aerospace vehicles. Ample works have been done to increase the accuracy and speed of the attitude estimation process, but all have been developed according to a model-based approach. This approach assumes that the torques acting on the body have a known dynamical model that is used for the attitude estimation. The purpose of the present research is to estimate the attitude via a model-free approach, i. e. dynamics of the torques acting on the body are no longer assumed to be known, and its learning is the next step. Thus, the problem formulation of this...

Stabilization and Pole-Placement by Structurally-Constrained Controllers: A Graph-Theoretic Approach

, M.Sc. Thesis Sharif University of Technology Moushaee, Pegah (Author) ; Babazadeh, Maryam (Supervisor)

Abstract

This thesis presents a new approach to design structural output feedback controllers with stabilization and pole-placement at desired points on the S plane. It is assumed that the linear time-invariant system has no fixed mode corresponding to the specified control structure, outside the desired region of the closed-loop poles, such that the structural controller design problem is theoretically feasible. To this end, the structural output controller design problem is first transformed into a structurally equivalent problem based on the solution of a set of discrete linear programs. Then, by using the resultant structure, a new method is proposed for designing static and dynamic control loops...

Fabrication of Thick Scaffold with Microfluidic Channels by Bioprinter

, M.Sc. Thesis Sharif University of Technology Khalighi, Sadaf (Author) ; Saadatmand, Maryam (Supervisor)

Abstract

Cardiovascular diseases are among the leading causes of death worldwide. For instance, in 2015, almost 31% of the world’s mortality rate was due to these causes. One of these diseases is cardiac coronary vessels’ occlusion which leads to the insufficient blood supply to the heart tissue and cardiomyocytes death after Myocardial Infarction (MI). After MI, a hierarchy of events in the heart tissue changes heart muscle and forms cardiac fibrosis. This fibrotic tissue does not have the native one’s properties and function, so it will cause cardiac arrest and patient death. Therefore, it is obvious that vascular network plays a crucial role in the heart function. The importance of cardiac...

Optimal Control of Unknown Interconnected Systems via Distributed Learning

, M.Sc. Thesis Sharif University of Technology Farjadnasab, Milad (Author) ; Babazadeh, Maryam (Supervisor)

Abstract

This thesis addresses the problem of optimal distributed control of unknown interconnected systems. In order to deal with this problem, a data-driven learning framework for finding the optimal centralized and the suboptimal distributed controllers has been developed via convex optimization.First of all, the linear quadratic regulation (LQR) problem is formulated into a nonconvex optimization problem. Using Lagrangian duality theories, a semidefinite program is then developed that requires information about the system dynamics. It is shown that the optimal solution to this problem is independent of the initial conditions and represents the Q-function, an important concept in reinforcement...

Fixed-Time Consensus Control of Unknown Multi-Agent Systems Based on Distributed Reinforcement Learning

, M.Sc. Thesis Sharif University of Technology Delshad, Aria (Author) ; Babazadeh, Maryam (Supervisor)

Abstract

This thesis introduces a distributed backstepping control strategy based on reinforcement learning to achieve fixed-time consensus in high-order nonlinear multi-agent systems. Each agent, whether a leader or a follower, is modeled using a strict feedback approach, incorporating uncertainties as unknown nonlinear functions and disturbance signals across all state variables. The communication network among agents can be either directed or undirected, with a fixed topology. Each follower employs a control law derived from actor-critic networks, utilizing only the outputs from neighboring agents. The proposed method combines virtual and actual backstepping control laws, formulated from two key...