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ahmadi-renani--s
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Trade in Intermediate Goods and The Welfare Gain from International Trade
, M.Sc. Thesis Sharif University of Technology ; Madanizadeh, Ali (Supervisor)
Abstract
In this thesis, I introduce a general equilibrium model of international trade that takes into account the industry linkages between intermediate goods and consumption goods producers to quantitatively measure the countries’ welfare gains and losses from different trade policies on intermediate and consumption goods. My model extends the inter-industry trade model of Ricardo (1817), intra-industry model of Krugman (1980), and firm heterogeneous model of Melitz (2003). Reduction of tariffs affect welfare of countries through direct effects on income, cost of export, and cost of input bundles of production (labor and intermediate goods), and indirectly through changes in term of trades, and...
A New Method for Measuring very Low Variation in Physical Parameters based on the Sensitivity to Conditions of Chaotic Systems
, M.Sc. Thesis Sharif University of Technology ; Zohoor, Hasan (Supervisor)
Abstract
Since the beginning of human civilization, improving the methods of measuring and identifying changes in order to improve the level of comfort and safety of human civilization is inevitable. The intrinsic property of high sensitivity to system conditions in chaos phenomena has led some researchers to use this feature for purposes of identifying and measuring changes. The most important bugs of previous researches in this area are the complexity, lack of coherence and dependence on the nominal parameters. By analyzing the effect of the type and magnitude of the initial deviation in a system parameter on all the characteristics of the Duffing system response in the chaotic regime, was observed...
Clinical validation of a smartphone-based handheld ECG device: A validation study
, Article Critical Pathways in Cardiology ; Volume 21, Issue 4 , 2022 , Pages 165-171 ; 1535282X (ISSN) ; Gharebaghi, M ; Kamalian, E ; Hajghassem, H ; Ghanbari, A ; Karimi, A ; Mansoury, B ; Dayari, M. S ; Khatmi Nemati, M ; Karimi, A ; Zarghami, M. H ; Vasheghani Farahani, A ; Sharif University of Technology
Lippincott Williams and Wilkins
2022
Abstract
Background: Remote cardiac monitoring and screening have already become an integral telemedicine component. The wide usage of several different wireless electrocardiography (ECG) devices warrants a validation study on their accuracy and reliability. Methods: Totally, 300 inpatients with the Nabz Hooshmand-1 handheld ECG device and the GE MAC 1200 ECG system (as the reference) were studied to check the accuracy of the devices in 1 and 6-limb lead performance. Simultaneous 10-second resting ECGs were assessed for the most common ECG parameters in lead I. Afterward, 6-lead ECGs (limb leads), were performed immediately and studied for their morphologies. Results: Of the 300 patients, 297 had...
Stimuli-responsive biomaterials: smart avenue toward 4D bioprinting
, Article Critical Reviews in Biotechnology ; 2023 ; 07388551 (ISSN) ; Jahangiri, S ; Zirak Hassan Kiadeh, S ; Rezvaninejad, S ; Ahmadi, Z ; Ahmadi, S ; Safarkhani, M ; Rabiee, N ; Sharif University of Technology
Taylor and Francis Ltd
2023
Abstract
3D bioprinting is an advanced technology combining cells and bioactive molecules within a single bioscaffold; however, this scaffold cannot change, modify or grow in response to a dynamic implemented environment. Lately, a new era of smart polymers and hydrogels has emerged, which can add another dimension, e.g., time to 3D bioprinting, to address some of the current approaches’ limitations. This concept is indicated as 4D bioprinting. This approach may assist in fabricating tissue-like structures with a configuration and function that mimic the natural tissue. These scaffolds can change and reform as the tissue are transformed with the potential of specific drug or biomolecules released for...
Stimuli-responsive biomaterials: smart avenue toward 4D bioprinting
, Article Critical Reviews in Biotechnology ; Volume 44, Issue 5 , 2024 , Pages 860-891 ; 07388551 (ISSN) ; Jahangiri, S ; Zirak Hassan Kiadeh, S ; Rezvaninejad, S ; Ahmadi, Z ; Ahmadi, S ; Safarkhani, M ; Rabiee, N ; Sharif University of Technology
2024
Abstract
3D bioprinting is an advanced technology combining cells and bioactive molecules within a single bioscaffold; however, this scaffold cannot change, modify or grow in response to a dynamic implemented environment. Lately, a new era of smart polymers and hydrogels has emerged, which can add another dimension, e.g., time to 3D bioprinting, to address some of the current approaches’ limitations. This concept is indicated as 4D bioprinting. This approach may assist in fabricating tissue-like structures with a configuration and function that mimic the natural tissue. These scaffolds can change and reform as the tissue are transformed with the potential of specific drug or biomolecules released for...
Optimal transactive market operations with distribution system operators
, Article IEEE Transactions on Smart Grid ; 2017 ; 19493053 (ISSN) ; Ehsan, M ; Shahidehpour, M ; Sharif University of Technology
2017
Abstract
Distribution system operator (DSO) has traditionally been responsible for the reliable operation of power distribution systems. The advent of distributed energy resources (DERs) and microgrids in distribution networks has required a new platform for DSOs. The new DSO, which is for the most part an independent agent, is responsible for aggregating a widely dispersed DERs (which include small thermal generation units, energy storage, and demand response) and flexible loads in electricity markets. DSO coordinates and balances the transactive dispatch of supply and demand at the distribution level and links wholesale and retail electricity markets. In this paper, a framework for the day-ahead...
Optimal transactive market operations with distribution system operators
, Article IEEE Transactions on Smart Grid ; Volume 9, Issue 6 , 2018 , Pages 6692-6701 ; 19493053 (ISSN) ; Ehsan, M ; Shahidehpour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Distribution system operator (DSO) has traditionally been responsible for the reliable operation of power distribution systems. The advent of distributed energy resources (DERs) and microgrids in distribution networks has required a new platform for DSOs. The new DSO, which is for the most part an independent agent, is responsible for aggregating a widely dispersed DERs (which include small thermal generation units, energy storage, and demand response) and flexible loads in electricity markets. DSO coordinates and balances the transactive dispatch of supply and demand at the distribution level and links wholesale and retail electricity markets. In this paper, a framework for the day-ahead...
Day-ahead self-scheduling of a transmission-constrained GenCo with variable generation units using the incomplete market information
, Article IEEE Transactions on Sustainable Energy ; Volume 8, Issue 3 , 2017 , Pages 1260-1268 ; 19493029 (ISSN) ; Ehsan, M ; Shahidehpour, M ; Sharif University of Technology
2017
Abstract
In this paper, a self-generation scheduling method for a power generation company (GenCo) with renewable generation units is presented. In the proposed method, locational market prices (LMPs) are calculated using the incomplete information on competing market participants by simulating the ISO's market clearing program and considering the effect of physical limitations of transmission lines. The errors associated with forecasted LMP and renewable production are modeled in the GenCo's generation scheduling using a robust optimization approach. The scheduling problem is modeled as a mixed-integer linear programming which is solved by a CPLEX solver in GAMS. An eight-bus system is employed to...
Axial potential mapping of optical tweezers for biopolymer stretching: The bead size matters
, Article Optics Letters ; Volume 38, Issue 5 , 2013 , Pages 685-687 ; 01469592 (ISSN) ; Reihani, S. N. S ; Sharif University of Technology
2013
Abstract
Optical tweezers (OT) are widely used for pico (and femto)-Newton range force measurements. The appropriate choice of the bead size is not well understood for biopolymer stretching applications of OT. We have shown, both by theory and experiment, that wrong choice of the bead size could cause errors as large as 295% in the measured force. We provide a simple map for correct choice of the bead size and the direction of pulling for such applications. There is a good agreement between our theoretical and experimental results
Fast maximum-likelihood decoder for quasi-orthogonal space-time block code
, Article Mathematical Problems in Engineering ; Volume 2015 , 2015 ; 1024123X (ISSN) ; Talebi, S ; Sharif University of Technology
Hindawi Publishing Corporation
2015
Abstract
Motivated by the decompositions of sphere and QR-based methods, in this paper we present an extremely fast maximum-likelihood (ML) detection approach for quasi-orthogonal space-time block code (QOSTBC). The proposed algorithm with a relatively simple design exploits structure of quadrature amplitude modulation (QAM) constellations to achieve its goal and can be extended to any arbitrary constellation. Our decoder utilizes a new decomposition technique for ML metric which divides the metric into independent positive parts and a positive interference part. Search spaces of symbols are substantially reduced by employing the independent parts and statistics of noise. Symbols within the search...
Amplitude reconstruction of clipped OFDM by using DFT-based least squares
, Article Scientia Iranica ; Volume 24, Issue 3 , 2017 , Pages 1353-1362 ; 10263098 (ISSN) ; Talebi, S ; Sharif University of Technology
2017
Abstract
OFDM is an effective multicarrier transmission technique with one primary disadvantage; it suffers from high Peak-to-Average Power Ratio (PAPR). Although clipping and filtering is a simple and effective method for PAPR reduction, it makes in-band and out-of-band noise, which degrades the bit error rate performance and spectral efficiency. Publications on this subject show that clipped samples could be reconstructed at the receiver by using oversampled signal and bandwidth expansion. By building on published literature, this paper aims to achieve a low-complexity method. The proposed method has complexity order of O(L2) to solve linear system, where L indicates the number of clipped samples....
Development of HAp/GO/Ag coating on 316 LVM implant for medical applications
, Article Journal of the Mechanical Behavior of Biomedical Materials ; Volume 126 , 2022 ; 17516161 (ISSN) ; Izanloo, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this study, antibacterial activity, biocompatibility, and corrosion resistance of 316 LVM implants were improved using the development of HAp/GO/Ag nanocomposite coatings by the dip-coating method. The XRD and FTIR results confirmed the synthesis of HAp/GO/Ag nanocomposites. HAp/Ag nanoparticles (68 nm) bound to epoxy, hydroxyl, and carboxyl functional groups on GO sheets (size of GO sheets varies from 255 to 1480 nm) by electrostatic interaction. FESEM images showed that HAp/GO/Ag coatings had higher density and fewer micro-cracks than pure HAp coatings. In addition, HAp/GO/Ag coatings showed optimized nano-hardness (4.5 GPa) and elasticity modulus (123 GPa). The results of...
Leveraging Swin Transformer for Local-to-Global Weakly Supervised Semantic Segmentation
, Article Iranian Conference on Machine Vision and Image Processing, MVIP ; 2024 ; 21666776 (ISSN); 979-835035049-4 (ISBN) ; Kasaei, S ; Sharif University of Technology
2024
Abstract
In recent years, weakly supervised semantic segmentation using image-level labels as supervision has received significant attention in the field of computer vision. Most existing methods have addressed the challenges arising from the lack of spatial information in these labels by focusing on facilitating supervised learning through the generation of pseudolabels from class activation maps (CAMs). Due to the localized pattern detection of Convolutional Neural Networks (CNNs), CAMs often emphasize only the most discriminative parts of an object, making it challenging to accurately distinguish foreground objects from each other and the background. Recent studies have shown that Vision...
Robust coordinated distribution system planning considering transactive DSO's market
, Article IEEE Transactions on Power Systems ; 2022 , Pages 1-11 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
In this paper, a robust distribution system expansion planning (DSP) approach is presented to supply the load growth locally and move toward nearly zero energy local distribution areas (LDAs). In the proposed approach, a distribution system operator (DSO) is responsible for secure and optimum operation of LDAs. Therefore, investors on distribution system upgrades use this approach to maximize the profit on investments by determining the installation year of new distribution feeders and energy resources, distributed energy resource (DER) placements and sizes considered by corresponding DSOs. The accurate AC power flow solution is used and mathematical methods are developed to model the DSP as...
Robust coordinated distribution system planning considering transactive DSO's market
, Article IEEE Transactions on Power Systems ; Volume 38, Issue 2 , 2023 , Pages 1894-1905 ; 08858950 (ISSN) ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In this paper, a robust distribution system expansion planning (DSP) approach is presented to supply the load growth locally and move toward nearly zero energy local distribution areas (LDAs). In the proposed approach, a distribution system operator (DSO) is responsible for secure and optimum operation of LDAs. Therefore, investors on distribution system upgrades use this approach to maximize the profit on investments by determining the installation year of new distribution feeders and energy resources, distributed energy resource (DER) placements and sizes considered by corresponding DSOs. The accurate AC power flow solution is used and mathematical methods are developed to model the DSP as...
Damage Assessment of Concrete under Compression Using Ultrasonic Test
, M.Sc. Thesis Sharif University of Technology ; Kazemi, Mohammad Taghi (Supervisor)Which Factors Determine Demand for Children Among the Iranian Urban Households?
, M.Sc. Thesis Sharif University of Technology ; Keshavarz Haddad, Gholamreza (Supervisor)
Abstract
This research intends to investigate demand for children among Iranian Urban Households in an intra-household bargaining decision process. Using, Household’s Expenditures Survey of Iran(2008), a count regression technique which takes into acount the over-dispersion and under-dispersion of Poisson scheme is specified as function of intra-household bargaining factors, and family’s characteristics. Our findings confirm the significance and a priory expected directions of distribution factors (intra-household bargaining power) and household’s characteristic, effects. Robustness checks verify the accuracy and appropriateness of the generalized Poisson. To examine the exogeneity explanatory...
Instagram and its Relation to Moral Values
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hassan (Supervisor)
Abstract
In this thesis, the value-ladenness or value-neutrality of technology, new social media and as a result Instagram is investigated. It is also discussed whether values can be taken into account during the design process of technical artefacts, including new social media and Instagram, and methods are developed for this purpose. Several methods have been developed for this purpose, some of them and their compatibility with modern social media are explained; including the Value-Sensitive-Design method and the disclosive computer ethics design method. The frameworks of ethical philosophy such as virtue ethics are reviewed and the appropriate ethical framework for the analysis of new social media...
Non-catalytic condensation of aromatic aldehydes with aniline in high temperature water
, Article Green Chemistry Letters and Reviews ; Volume 5, Issue 3 , Mar , 2012 , Pages 403-407 ; 17518253 (ISSN) ; Hosseinpour, M ; Sadjadi, S ; Sharif University of Technology
T&F
2012
Abstract
The synthesis of diamino triphenyl methanes from aniline and aromatic aldehydes was conducted in near critical water and supercritical water. The reaction parameters, such as temperature, density, and reaction time, have been studied. Significant acceleration of the condensation reaction of aniline and aromatic aldehydes can be achieved by using high temperature water, especially near the critical point, in the absence of any acid catalysts. It has been demonstrated that high temperature water act effectively in the place of conventional acid catalysts
Adsorption behavior of toxic metal Ions on nano-structured CuO granules
, Article Separation Science and Technology (Philadelphia) ; Volume 47, Issue 7 , 2012 , Pages 1063-1069 ; 01496395 (ISSN) ; Sadjadi, S ; Hosseinpour, M ; Sharif University of Technology
2012
Abstract
In this study, copper oxide nano particles were synthesized by batchwise supercritical hydrothermal method. After preparation of CuO nano particles, they were immobilized into the porous matrix of sodium alginate. The drying process formed a very porous structure that is useful for enhancing of adsorption activity. Produced CuO particles were characterized by X-ray diffractometery (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and BET for measuring the surface area. The prepared materials were then used as adsorbent in the removal of toxic metal ions in aqueous solution. To optimize the adsorption system, the effect of various parameters such as adsorbent...