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Determination and prioritization of criteria to design urban energy resilience conceptual model (part 2)
, Article International Journal of Environmental Science and Technology ; Volume 20, Issue 9 , 2023 , Pages 9649-9662 ; 17351472 (ISSN) ; Abbaspour, M ; Sharif University of Technology
Institute for Ionics
2023
Abstract
Currently, approximately 60% of the global population resides in urban areas. Urban energy resilience can be distinguished into two categories: short-term resilience—the ability to cope with natural disasters, and long-term resilience—the ability to withstand the adverse impacts of climate change. In this study, the outcomes of the previous study, which prioritized 34 sub-criteria based on a four-factor classification: technical/infrastructural, built environment, governance, and socio-cultural aspects of both short and long-term approaches, are employed as the basis for the comprehensive resilience management model. The fuzzy analytic hierarchy process is used to quantify each resilience...
Determination and prioritization of criteria to design urban energy resilience conceptual model (Part 1)
, Article International Journal of Environmental Science and Technology ; Volume 19, Issue 5 , 2022 , Pages 3593-3606 ; 17351472 (ISSN) ; Abbaspour, M ; Ghodoosi, J ; Sharifi, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Nowadays, around 70% percent of global energy usage is consumed in urban areas. Undoubtedly, this figure will increase in coming decades due to population rise. As a result, energy resiliency can be considered as an important issue in urban context. Resilience of energy supply in urban areas can be categorized in two approaches, short-term and long-term. Short-term applies to cope with threats such as earthquakes and floods, and long-term applies to deal with impacts of climate change on global warming. In this study, literature review was applied to design questionnaire for expert survey, followed by Fuzzy analytic hierarchy process method to categorize 34 sub-criteria divided under four...
BiPO4 photocatalyst employing synergistic action of Ag/Ag3PO4 nanostructure and graphene nanosheets
, Article Solid State Sciences ; Volume 56 , 2016 , Pages 10-15 ; 12932558 (ISSN) ; Rahimi, E ; Sharif University of Technology
Elsevier Masson SAS
2016
Abstract
Graphene-supported BiPO4/Ag/Ag3PO4 photocatalyst has been fabricated by simple hydrothermal and impregnation reaction. In BiPO4/Ag/Ag3PO4 based on Reduced Graphene Oxide (RGO), this network renders numerous pathways for rapid mass transport, strong adsorption and multireflection of incident light; meanwhile, the interface between BiPO4/Ag/Ag3PO4 and RGO increases the active sites and electron transfer rate. BiPO4/Ag/Ag3PO4 based on RGO noticeably exhibited high photocatalytic activity than that of BiPO4/Ag/Ag3PO4 and P25 under visible light irradiation for cationic dye (Rhodamine B), anionic dye (methyl orange) and 4-chlorophenol (4-CP) as a neutral pollutant, which are usually difficult to...
A joint exprimental and theoretical study on ZnO nanocomposites synthesised by a liquid deposition method
, Article Progress in Reaction Kinetics and Mechanism ; Volume 40, Issue 3 , July , 2015 , Pages 261-278 ; 14686783 (ISSN) ; Zeidabadi Nejad, L ; Tasviri, M ; Dehestani, M ; Haqgu, M ; Gholami, M. R ; Sharif University of Technology
Science Reviews 2000 Ltd
2015
Abstract
ZnO was grown on mordenite zeolite, activated carbon and alumina substrates by a liquid deposition method. The photocatalytic activity of the synthesised samples was elucidated using the photodegradation of Acid Blue 92 (AB92) dyes as a test pollutant under UV light irradiation. Supports play a key role in AB92 photodegradation and significantly improve the photocatalytic activity of ZnO. Different supports form additional transport channels and provide an effective pathway for the charge carriers. The supports effectively construct porous structures with more active sites. Hence, the higher photocatalytic activity of supported catalysts is attributed to the large surface area and charge...
A sampling theorem for convex shapes with algebraic boundaries
, Article 2017 12th International Conference on Sampling Theory and Applications, SampTA 2017, 3 July 2017 through 7 July 2017 ; 2017 , Pages 499-503 ; 9781538615652 (ISBN) ; Amini, A ; Sharif University of Technology
2017
Abstract
In this paper we present a sampling result about continuous-domain black and white images that form a convex shape. In particular, we will study shapes whose boundaries belong to the zero-level sets (roots) of bivariate polynomials. In [1] it was shown that generalized 2D moments of the image can lead to annihilation equations for the coefficients of the bivariate polynomial that determine the boundary of the shape. More precisely, when the bivariate polynomial is of degree n (which has n(n+3)/2 non-trivial coefficients), the results in [1] indicate that for invertibility of the linear annihilation equations, 2D moments of up to degree 3n-1 (overall equation moments) are required. In this...
The effect of conductivity on current distribution in the Hull cell
, Article Plating and Surface Finishing ; Volume 89, Issue 1 , 2002 , Pages 50-52 ; 03603164 (ISSN) ; Sharifabadi, Sh. A ; Zahed, M. N ; Sharif University of Technology
2002
Abstract
In this study, current distribution data were obtained from a controlled variation of electrolyte conductivity, using a 267 mL Hull cell. Current distribution measurement was made using a sectioned electrode. The current density for each strip was calculated by measuring the weight gain of the strips during plating and applying Faraday's Law. Finally, the Hull cell formula was derived by plotting the regression line for current density versus average logarithmic distance along the segmented Hull cell panel. Three systems were studied: acid sulfate copper, all-chloride nickel, and all-chloride zinc. We found that the solution conductivity affects the current distribution. As the conductivity...
Proposed Method for Selecting the Most Suitable Contractor Using Risk Analysis
, M.Sc. Thesis Sharif University of Technology ; Mortaheb, Momamad Mehdi (Supervisor)
Abstract
At present, with some exceptions, the contracts are awarded based on the least proposed price. The records show that this method has not been successful especially for the infrastructure projects. In other words the projects awarded this way have been completed with time and cost overruns. Most of the times, such projects have not satisfied the stakeholders' expectations or have had problems during operation phase. The goal of this research is to suggest a method for selecting the most suitable contractor, considering the proposed price as well as incorporating the delay and other risks based on Contractors' actual past performance in the completed projects. Before selecting the Contractor,...
Determination of Strain Dependent Dynamic Parameters of Unsaturated a Silty Soil During Drying path using Resonant Column-Torsional Shear Device
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Shear modulus and damping ratio are the most important parameters for evaluating the performance of geotechnical systems under seismic and dynamic loads. According to the definition, secant shear modulus is the slope of the hysteresis shear stress-shear strain loop and damping ratio indicates the dissipation of wave energy during propagation in the soil. These parameters depend on stress state, shear strain and void ratio of the soil. Shear strain amplitude has an important effect on the behavior of shear modulus and damping ratio and it is necessary to study the behavior of these parameters in the range of small to large strains. In addition to dynamic loading, climate change and wet and...
Determining the optimum heap height considering the irrigation rate and the slope of heap bed variations in miduk copper mine
, Article Acta Physica Polonica A ; Volume 128, Issue 2 , 2015 , Pages 352-354 ; 05874246 (ISSN) ; Rahimi, E ; Mohaghegh, N ; Sharif University of Technology
Polish Academy of Sciences
2015
Abstract
Determining an optimum height is remarked as one of the most important issues in heap designing and this is obtained by calculating the number and the height of heap lifts. Although the increase of lift height has benefits in heap leaching method from economic point of view, it will reduce the stability and make process problems such as low permeability. The current paper analyzes the effect of sulphuric acid irrigation on the strength parameters of Miduk oxide copper ores. In addition, the result of the process experiments have evaluated with different irrigation rates as well as variable conditions of permeability. From process view, approximately 75% of copper is recovered at irrigation...
An evaluation of the effect of matric suction on the dynamic strain-dependent parameters of an unsaturated silt
, Article E3S Web of Conferences ; Volume 382 , 2023 ; 25550403 (ISSN) ; Sadollahzadeh, B ; Zahed, V ; Bardanis M ; Sharif University of Technology
EDP Sciences
2023
Abstract
This research investigates the influence of matric suction on the variation of shear modulus and damping ratio of a silty soil in very small to medium shear strain levels. A set of laboratory experiments including three bender elements tests in addition to three resonant column-torsional shear tests have been carried out on unsaturated Firuzkuh silt specimens. In this regard, an unsaturated triaxial cell equipped with a set of bender elements and a resonant column-torsional shear device that can apply and control matric suction have been used. All specimens had an initial void ratio of 0.7 and were tested in various matric suctions under a net mean stress of 50 kPa. For this purpose, the...
Ag3PO4/BiPO4 p-n heterojunction nanocomposite prepared in room-temperature ionic liquid medium with improved photocatalytic activity
, Article Materials Science in Semiconductor Processing ; Volume 39 , 2015 , Pages 506-514 ; 13698001 (ISSN) ; Rahimi, E ; Gholami, M. R ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Abstract A visible-light-active Ag3PO4/BiPO4 nanocomposite with a p-n heterojunction structure was fabricated via a co-precipitation hydrothermal process using 2-hydroxylethylammonium formate (RTIL) as a room-temperature ionic liquid. The resulting catalysts were characterized by various techniques. The photocatalytic activity of the photocatalysts was evaluated by the photodegradation of phthalocyanine Reactive Blue 21 (RB21) under both visible and UV light irradiations. The results reveal that the heterojunction composite prepared in RTIL noticeably exhibited an improvement in both efficiency and rate of RB21 photodegradation in comparison with pure Ag3PO4 and BiPO4. The enhanced...
Design of Toeplitz Measurement Matrices with Applications to Sparse Channel Estimation in Single-Carrier Communication
, M.Sc. Thesis Sharif University of Technology ; Amini, Arash (Supervisor)
Abstract
Channel estimation is one of the fundamental challenges in every communication system and different algorithms have been proposed to deal with it. Obviously, type of a communication channel is an important factor in choosing the appropriate method for channel estimation. Sparse channels are one kind of them that occur in many real-world applications such as wireless communication systems. In addition, emergence of a new means in signal processing to deal with sparse signals, known as Compressed Sensing(CS), paved the way for their extensive usage in many applications including sparse channel estimation.On the other hand, one of the most fundamental problems in sparse signal recovery using CS...
Partially stabilization of Zirconia and its effects on the Magnesia - Spinel refractory properties
, Article UNITECR '05 - Unified International Technical Conference on Refractories: 9th Biennial Worldwide Congress on Refractories, Orlando, FL, 8 November 2005 through 11 November 2005 ; 2006 , Pages 715-721 ; 1574982656 (ISBN) ; Nemati, Z. A ; Faghihi Sani, M. A ; Zahed, F ; Sharif University of Technology
2006
Abstract
In this research, Magnesia Spinel refractories were formulated by using sintered magnesia, Tabular and Calcined Alumina and sintered Spinel. The grain size distribution of raw materials was modified, using the Andreessen equation. In order to improve the physical and mechanical properties and corrosion resistance of specimens, none stabilized Zirconia was added to the system. The pressed samples were sintered at 1700°C and the properties were evaluated at room and high temperatures. The formed phases and resultant microstructure were also, analyzed by XRD and SEM. The corrosion test was conducted in two parts. First, the depth of corrosion was measured in two zone, within 0-1mm and 1-2 mm...
Enhancing the photocatalytic performance of Ag3PO4 by incorporating g-C3N4 and MWCNTs: Optimisation of removal of Acid Blue 92
, Article Progress in Reaction Kinetics and Mechanism ; Volume 41, Issue 3 , 2016 , Pages 277-288 ; 14686783 (ISSN) ; Armandsefat, F ; Mohaghegh, N ; Ahmadinasab, N ; Sharif University of Technology
Science Reviews 2000 Ltd
2016
Abstract
The main aim of the present study was to enhance the degradation capacity of Acid Blue 92 (AB92) by visible-light-active Ag3PO4 nanocomposites based on g-C3N4 and Multiwalled Carbon Nanotubes (MWCNTs). The nanocomposites were fabricated through a tunable in situ deposition method. The properties of the resulting samples were investigated by X-ray diffraction, scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. The photocatalytic activity results revealed that the Ag3PO4/g-C3N4 heterojunction inorganic/organic composite exhibited an improvement in both efficiency and the rate of AB92 photodegradation in comparison with the others. The enhanced photocatalytic...
An Investigation on the Size and the Welfare of Different Income Groups During 1376-1399 and an Estimation of the Mobility of the Iranian Urban Low-Income Households
, M.Sc. Thesis Sharif University of Technology ; Nili, Masoud (Supervisor) ; Mohaghegh, Mohsen (Supervisor)
Abstract
In this study, based on Households Income and Expenditure Survey (HIES) data, we examined the socio-economic characteristics and transition of Iranian urban households in each of the three different income groups from 1997 to 2020. Moreover, factors affecting entry to poverty or persistence in poverty in Iranian urban households are discussed.The results of this study show that, contrary to popular belief, there is no evidence of accumulation of entrepreneurs and business owners in the urban middle class. Rather, middle-income households have higher-skilled jobs and pay more for social security than low-income ones, as well as pay more attention to investing in human capitals (education and...
Managing Mega Project Construction Project with Method of Cost Management Approach (Case Study on the world’s fourth Mega Project)
, M.Sc. Thesis Sharif University of Technology ; Rafie, Majid (Supervisor) ; Khalou, Alireza (Co-Supervisor)
Abstract
One of the features of a project is its uniqueness, if two sets of activities are the same neither of them will longer be included in the project definition. A method in two projects with the same nature may yield inverse results of each other. Therefore, it is necessary to study the parameters affecting the project carefully before any action. So far, some research has been conducted in this area and it has been tried to perform case study on qualitative and quantitative parameters of the project. By investigating a number of common factors in most civil engineering projects, especially megaprojects, the present study attempts to identify and examine exquisite and effective parameters and...
Experimental Investigation of Aerodynamic Performance Enhancement by Trailing Edge Active Flow Control Using Plasma Actuator
,
M.Sc. Thesis
Sharif University of Technology
;
Ebrahimi, Abbas
(Supervisor)
Abstract
Flow control means changing the optimal flow behavior of the fluid in accordance with the desired targets, such as decreasing drag force, increasing the lift force or lift to drag ration, as well as manipulating the separation of the flow from the surface. So far, little research has been done on increasing the airflow performance through the active control of the trailing edge flow. Gurney flap is a great tool, and its experimental results show a significant increase lift force in the airfoil. In this study, it is possible experimentally to use plasma actuators to create microtap and garney flap artificial for enhancing the aerodynamic performance of airfoil by controlling the flow field at...
Electrodeposited multi-walled carbon nanotubes on Ag-loaded TiO2 nanotubes/Ti plates as a new photocatalyst for dye degradation
, Article RSC Advances ; Volume 5, Issue 56 , 2015 , Pages 44840-44846 ; 20462069 (ISSN) ; Faraji, M ; Gobal, F ; Gholami, M. R ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
MWCNTs/Ag/TiO2NTs plates were synthesized via electrochemical reduction of functionalized multiwalled carbon nanotubes (MWCNTs) on Ag/TiO2NTs. The loading of silver nanoparticles was carried out by electroless reduction of Ag1+ onto TiO2 nanotubes previously formed by anodizing titanium. The SEM analysis revealed that MWCNTs were loaded significantly on the as-prepared Ag/TiO2NTs, where nanoparticles of Ag had grown on the walls of TiO2NTs. The photocatalytic activity of the synthesized plates was evaluated by the photodegradation of Methyl Orange (MO) dye under UV light irradiation. The results indicated that the MWCNTs/Ag/TiO2NTs demonstrated improved efficiency for MO photodegradation in...
Comparative studies on Ag3PO4/BiPO4-metal-organic framework-graphene-based nanocomposites for photocatalysis application
, Article Applied Surface Science ; Volume 351 , October , 2015 , Pages 216-224 ; 01694332 (ISSN) ; Tasviri, M ; Rahimi, E ; Gholami, M. R ; Sharif University of Technology
Elsevier
2015
Abstract
For the first time, we report novel Ag3PO4/BiPO4 (AB)-graphene-based photocatalysts. The fabricated nanocomposites were characterized by various techniques. The photocatalytic properties of the prepared catalysts were evaluated by the photodegradation of Atrazine herbicide under both visible and UV light irradiation. Atrazine concentration was determined using the spectrophotometric method according to the Konig's reaction by monitoring the absorbance at 470 nm wavelength during the photodegradation process. Both degradation rate and efficiency using graphene (GR)-based nanocomposites are found to be much better than using pure AB. Atrazine photodegradation displayed that the AB supporting...
Ag2CO3 sensitized TiO2 nanoparticles prepared in ionic liquid medium: A new Ag2CO3/TiO2/RTIL heterostructure with highly efficient photocatalytic activity
, Article Journal of Molecular Catalysis A: Chemical ; Volume 406 , 2015 , Pages 152-158 ; 13811169 (ISSN) ; Eshaghi, B ; Rahimi, E ; Gholami, M. R ; Sharif University of Technology
Elsevier
2015
Abstract
Abstract A visible light active Ag2 CO3 /TiO2 /2-hydroxylethylammonium formate (RTIL) nanocomposite has been synthesized via loading Ag2 CO3 flower-like particles on TiO2 /RTIL by a simple precipitation method. TiO2 nanoparticles were prepared by the modified sol-gel method using 2-hydroxylethylammonium formate (RTIL) as an ionic liquid. The prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform-infra red spectroscopy (FTIR) and Diffuse reflectance UV-vis spectroscopy (DRS) techniques. The photocatalytic performance of the synthesized photocatalysts...