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barzegar--milad
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Does the short-term boost of renewable energies guarantee their stable long-term growth? Assessment of the dynamics of feed-in tariff policy
, Article Renewable Energy ; Volume 159 , October , 2020 , Pages 1252-1268 ; Hamed Shakouri, G ; Mashayekhi, A. N ; Kazemi, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Feed-in tariff (FiT) is one of the most efficient ways that many governments throughout the world use to stimulate investment in renewable energies (REs) technology. For governments, financial management of the policy could be challenging as it needs a considerable amount of budget to support RE producers during the long remuneration period. In this paper, it has been illuminated that the early growth of REs capacity could be a temporary boost. And the socio-economic structure of the system will backlash the policy if some social mechanisms are not considered. Social tolerance for paying REs tax and potential investors’ trust emanated from budget-related mechanisms -which have rarely been...
QBism is not so simply dismissed
, Article Foundations of Physics ; Volume 50, Issue 7 , 2020 , Pages 693-707 ; Sharif University of Technology
Springer
2020
Abstract
QBism is one of the main candidates for an epistemic interpretation of quantum mechanics. According to QBism, the quantum state or the wavefunction represents the subjective degrees of belief of the agent assigning the state. But, although the quantum state is not part of the furniture of the world, quantum mechanics grasps the real via the Born rule which is a consistency condition for the probability assignments of the agent. In this paper, we evaluate the plausibility of recent criticism of QBism. We focus on the consequences of the subjective character of the quantum state, the issue of realism and the problem of the evolution of the quantum state in QBism. In particular, drawing upon...
Effect of the Fluctuations of Quantum Chromodynamics Topological Charge on the Dispersion Relation of NJL Model
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
One of the long-lived problems in the theory of quantum chromo dynamics is the violation of parity (P) and charge-parity (CP) symmetries in strong interactions. The existence of gluon configurations sourcing from topology leads to degeneracy in the vacuum structure of the theory. This phenomenon is realized by the addition of an extra term proportional to the parameter to QCD Lagrangian. Experimental estimates of neutron electric dipole, predicts a very small value for this parameter. There is no verified justification for this discrepancy. Recently at the relativistic heavy ion collider laboratory (RHIC) some experimental evidence has been found which indicates local CP violation in...
Calculation of effective parameters of high permittivity integrated artificial dielectrics
, Article IET Microwaves, Antennas and Propagation ; Volume 9, Issue 12 , September , 2015 , Pages 1287-1296 ; 17518725 (ISSN) ; Rejaei ; Sharif University of Technology
Institution of Engineering and Technology
2015
Abstract
An analysis is presented of the effective electromagnetic parameters of high-permittivity, anisotropic artificial dielectrics which are built by stacking arrays of metallic elements and conventional dielectric films, with adjacent arrays shifted with respect to each other. The effective parameters of the artificial dielectric are extracted from the scattering coefficients of plane electromagnetic waves which are normally or obliquely incident on a slab of the artificial material with finite thickness. These coefficients are derived from the generalised scattering matrix of a single layer of metallic elements which is computed using the integral equation technique. Both two-dimensional and...
Determinantal Processes
, M.Sc. Thesis Sharif University of Technology ; Alishahi, Kasra (Supervisor)
Abstract
Determinantal processes are a special family of stochastic processes that arise in physics (fermions), random matrices (eigenvalues), and in combinatorics (random spanning trees and non-intersecting paths). These processes have repelling property (points close to each other are chosen with low probability). Because of this repelling property, determinantal processes are approporiat for modeling some physical quantities (e.g. the position of electrons). Their probabilistic structure is described by operators on complex vector spaces and their eigenvalues. Determinantal processes have interesting properties, e.g. number of points in a region is a sum of independent Bernoulli random variables....
Evaluation of Performance Based Plastic Design Method in Dual Moment Frame-shear Wall Concrete Systems
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
Performance – based design is a new concept that has been developed in recent years. Given that roof displacement and story drifts determine the performance of the structure during an earthquake, displacement – based design has been considered to be an effective method for performance – based design. However, limiting the maximum displacement would not necessarily lead to a desirable performance; especially in long – duration earthquakes. Thus consecutive loading cycles and the effect of hysteretic energy should be taken into account. Combining displacement – based design with energy principles will lead to a suitable design method. This study presents performance – based plastic design...
Two-dimensional materials for gas sensors: from first discovery to future possibilities
, Article Surface Innovations ; Volume 6, Issue 4-5 , 2018 , Pages 205-230 ; 20506252 (ISSN) ; Tudu, B ; Sharif University of Technology
ICE Publishing
2018
Abstract
Semiconductor gas sensors have been developed so far on empirical bases, but now recent innovative materials for advancing gas sensor technology have been made available for further developments. Two-dimensional (2D) materials have gained immense attention since the advent of graphene. This attention inspired researchers to explore a new family of potential 2D materials. The superior structural, mechanical, optical and electrical properties of 2D materials made them attractive for next-generation smart device applications. There are considerable improvements and research studies on graphene, molybdenum disulfide (MoS2), tungsten disulfide (WS2), tin sulfide (SnS2), black phosphorus and other...
Brain tumor segmentation based on 3D neighborhood features using rule-based learning
, Article 11th International Conference on Machine Vision, ICMV 2018, 1 November 2018 through 3 November 2018 ; Volume 11041 , 2019 ; 0277786X (ISSN); 9781510627482 (ISBN) ; Jamzad, M ; Sharif University of Technology
SPIE
2019
Abstract
In order to plan precise treatment or accurate tumor removal surgery, brain tumor segmentation is critical for detecting all parts of tumor and its surrounding tissues. To visualize brain anatomy and detect its abnormalities, we use multi-modal Magnetic Resonance Imaging (MRI) as input. This paper introduces an efficient and automated algorithm based on the 3D bit-plane neighborhood concept for Brain Tumor segmentation using a rule-based learning algorithm. In the proposed approach, in addition to using intensity values in each slice, we consider sets of three consecutive slices to extract information from 3D neighborhood. We construct a Rule base using sequential covering algorithm. Through...
Brain tumor segmentation based on 3D neighborhood features using rule-based learning
, Article 11th International Conference on Machine Vision, ICMV 2018, 1 November 2018 through 3 November 2018 ; Volume 11041 , 2019 ; 0277786X (ISSN) ; 9781510627482 (ISBN) ; Jamzad, M ; Sharif University of Technology
SPIE
2019
Abstract
In order to plan precise treatment or accurate tumor removal surgery, brain tumor segmentation is critical for detecting all parts of tumor and its surrounding tissues. To visualize brain anatomy and detect its abnormalities, we use multi-modal Magnetic Resonance Imaging (MRI) as input. This paper introduces an efficient and automated algorithm based on the 3D bit-plane neighborhood concept for Brain Tumor segmentation using a rule-based learning algorithm. In the proposed approach, in addition to using intensity values in each slice, we consider sets of three consecutive slices to extract information from 3D neighborhood. We construct a Rule base using sequential covering algorithm. Through...
A reliable ensemble-based classification framework for glioma brain tumor segmentation
, Article Signal, Image and Video Processing ; Volume 14, Issue 8 , 2020 , Pages 1591-1599 ; Jamzad, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2020
Abstract
Glioma is one of the most frequent primary brain tumors in adults that arise from glial cells. Automatic and accurate segmentation of glioma is critical for detecting all parts of tumor and its surrounding tissues in cancer detection and surgical planning. In this paper, we present a reliable classification framework for detection and segmentation of abnormal tissues including brain glioma tumor portions such as edemas and tumor core. This framework learns weighted features extracted from the 3D cubic neighborhoods regarding to gray-level differences that indicate the spatial relationships among voxels. In addition to intensity values in each slice, we consider sets of three consecutive...
Numerical study of Geostationary Orbit thermal cycle effects of a tubular adhesive joint: Dynamic behavior
, Article Journal of Adhesion ; Volume 96, Issue 16 , 2020 , Pages 1431-1448 ; Mokhtari, M ; Sharif University of Technology
Bellwether Publishing, Ltd
2020
Abstract
Space environments have a significant influence on advanced composite structures and adhesive joints. Degradation in the mechanical properties of aerospace materials changes the dynamic behavior of the structures and adhesive joints. In this paper, a typical tubular adhesive joint with material degradation due to geostationary orbit (GEO) thermal cycles has been studied numerically with Python scripts. Adhesive joint geometry and boundary conditions are the main parametric study parameters. The results show that the first non–zero natural frequencies of the clamped-free tubular adhesive joint decreased due to mechanical property degradation. A dynamic behavior comparison of the degradation...
WLFS: Weighted label fusion learning framework for glioma tumor segmentation in brain MRI
, Article Biomedical Signal Processing and Control ; Volume 68 , 2021 ; 17468094 (ISSN) ; Jamzad, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Glioma is a common type of tumor that develops in the brain. Due to many differences in the shape and appearance, accurate segmentation of glioma for identifying all parts of the tumor and its surrounding tissues in cancer detection is a challenging task in cancer detection. In recent researches, the combination of atlas-based segmentation and machine learning methods have presented superior performance over other automatic brain MRI segmentation algorithms. To overcome the side effects of limited existing information on atlas-based segmentation, and the long training and the time consuming phase of learning methods, we proposed a semi-supervised learning framework by introducing a...
Optimal Design of Induction MHD Generator for Electrical Power Generation from Exhaust of the Gas Turbine Power Plants
, M.Sc. Thesis Sharif University of Technology ; Boroushaki, Mehrdad (Supervisor)
Abstract
Today, due to increasing electricity consumption and demand, the use of conventional systems such as thermal, hydro and nuclear power plants is not enough to convert energy. Over the past century, scientists have sought to discover new technologies for exploiting different forms of energy and converting them into high-efficiency electrical energy. One of these ways is to use the phenomenon of magnetohydrodynamics (magnetic fluid dynamics) to convert thermal energy directly into electrical energy. Magnetohydrodynamics is a theoretical field that studies the dynamics of fluids with electrical conductivity. Induction magneto-hydrodynamic generators use ionized hot plasma (a quasi-neutral gas of...
A correlative model to predict in vivo AUC for nanosystem drug delivery with release rate-limited absorption
, Article Journal of Pharmacy and Pharmaceutical Sciences ; Volume 15, Issue 4 , 2012 , Pages 583-591 ; 14821826 (ISSN) ; Mohammadi, K ; Mohammadi, G ; Valizadeh, H ; Barzegar Jalali, A ; Adibkia, K ; Nokhodchi, A ; Sharif University of Technology
2012
Abstract
Purpose. Drug release from nanosystems at the sites of either absorption or effect biophase is a major determinant of its biological action. Thus, in vitro drug release is of paramount importance in gaining insight for the systems performance in vivo. Methods. A novel in vitro in vivo correlation, IVIVC, model denoted as double reciprocal area method was presented and applied to 19 drugs from 55 nano formulations with total 336 data, gathered from literature. Results. The proposed model correlated the in vitro with in vivo parameters with overall error of 12.4 ± 3.9%. Also the trained version of the model predicted the test formulations with overall error of 15.8 ± 3.7% indicating the...
Tamper Detection in Digital Images Using Transform Domains
,
M.Sc. Thesis
Sharif University of Technology
;
Jamzad, Mansour
(Supervisor)
Abstract
Nowadays, digital images are easy to manipulate and edit due to availability of powerful image processing and editing software. It is possible to add or remove important features to the image without leaving any obvious traces of tampering. Therefore, proving the authenticity and integrity of digital media becomes increasingly important. In this study, we focus on detection of a special type of digital forgery, the copy-move attack, in which a part of the image is copied and pasted somewhere else in the image with the intent to cover an important image features or to add some fake feature. In this way we propose some novel methods that work in spatial domain, Discrete Cosine domain and...
Analysis of Time-Modality Relationship in Diodorus Cronus Master Argument from the Viewpoint of Modern Logic
, M.Sc. Thesis Sharif University of Technology ; Nabavi, Lotfollah (Supervisor)
Abstract
Diodorus Cronus, the Megaric Logician, in an attempt to define possibility and necessity, formulated an argument which after him was known as Diodorus Cronus Master Argument. According to extant historical accounts, Master Argument consists of three premises which according to Diodorus form an inconsistency, so that results in the rejection of Aristotelian notion of possibility and establishment of determinism. But the argument itself i.e. how three premises of the Master Argument form an inconsistency, has been lost. Therefore a number of logicians has decided to reconstruct the Master Argument and thereby reveal its inner structure in order to evaluate its validity.
On the other hand,...
On the other hand,...
Millimeter-wave artificial dielectric waveguides for integrated applications
, Article IEEE MTT-S International Microwave and RF Conference 2014, IMaRC 2014 - Collocated with Intemational Symposium on Microwaves, ISM 2014, 15 December 2014 through 17 December 2014 ; 2015 , Pages 225-228 ; 9781479963164 (ISBN) ; Rejaei, B ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
High-quality guided wave devices are key components in integrated millimeter-wave circuits. In this paper, we propose mm-wave planar dielectric waveguides based on thin, anisotropic artificial dielectric layers with very high in-plane permittivity. Waves propagating on such films are surface waves whose field exponentially decays outside the film in the vertical direction, similar to waveguides commonly used in integrated optics. The very high in-plane permittivity of the artificial dielectric layers leads to strong field confinement, and allows the implementation of relatively thin waveguides. This fact, together with the planar structure of these devices, make them highly suitable for...
An exact method for the extraction of effective bulk and surface parameters of periodic artificial media
, Article IEEE Transactions on Antennas and Propagation ; Volume 63, Issue 6 , 2015 , Pages 2521-2531 ; 0018926X (ISSN) ; Rejaei, B ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
A new method is presented for the extraction of the bulk and surface parameters of a periodic artificial medium which uses the eigenvectors of the generalized transfer matrix of a unit layer. These eigenvectors correspond to the Bloch modes of the periodic structure. The eigenvector related to the propagating Bloch mode directly yields an expression for the effective, intrinsic wave impedance of the medium. Moreover, the interface between the artificial material and a surrounding, conventional (dielectric) region is described by an interface impedance matrix which accounts for the excitation of higher order, nonpropagating Bloch modes at the interface. Although these modes do not propagate...
Tunable extraordinary transmission through a graphene-covered hole array: an analytical equivalent-circuit modeling approach
, Article Plasmonics ; 2018 ; 15571955 (ISSN) ; Khavasi, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
We study two-dimensional (2D) hole arrays drilled into a perfect conductor slab covered with a graphene sheet. Such arrays support the extraordinary transmission of electromagnetic waves and allow tunability via graphene properties. We investigate the effect of graphene on transmission spectra by proposing an accurate analytical circuit model for the structure, where the graphene contributes an admittance component at the interface. The model demonstrates how extraordinary transmission can be tuned via the graphene conductivity. We study the free-standing structure, where the hole array is covered by a graphene sheet on both sides of the conductor slab, and a substrate-bound hole array...
Tunable extraordinary transmission through a graphene-covered hole array: an analytical equivalent-circuit modeling approach
, Article Plasmonics ; Volume 14, Issue 3 , 2019 , Pages 569-577 ; 15571955 (ISSN) ; Khavasi, A ; Sharif University of Technology
Springer New York LLC
2019
Abstract
We study two-dimensional (2D) hole arrays drilled into a perfect conductor slab covered with a graphene sheet. Such arrays support the extraordinary transmission of electromagnetic waves and allow tunability via graphene properties. We investigate the effect of graphene on transmission spectra by proposing an accurate analytical circuit model for the structure, where the graphene contributes an admittance component at the interface. The model demonstrates how extraordinary transmission can be tuned via the graphene conductivity. We study the free-standing structure, where the hole array is covered by a graphene sheet on both sides of the conductor slab, and a substrate-bound hole array...