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Image Registration Using Graph-based Methods
, M.Sc. Thesis Sharif University of Technology ; Fatemizadeh, Emadeddin (Supervisor)
Abstract
Nowadays, image registration is considered as one of usual issues in medical researches whose new findings are expanding outstandingly and it has reached a high level of maturity. Generally speaking, image registration is a task to reliably estimate the geometric transformation such that two images can be precisely aligned. With respect to different uses of image registration in medical applications, it has attracted the attention of many scholars and there has been made significant improvement in this realm. Image registration is still one of the active branches in medical image processing due to its wide applications and problems. Graphs, thanks to their geometric structures and intuitive...
GMWASC: Graph matching with weighted affine and sparse constraints
, Article CSSE 2015 - 20th International Symposium on Computer Science and Software Engineering, 18 August 2015 ; 2015 ; 9781467391818 (ISBN) ; Ghaffari, A ; Fatemizadeh, E ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Graph Matching (GM) plays an essential role in computer vision and machine learning. The ability of using pairwise agreement in GM makes it a powerful approach in feature matching. In this paper, a new formulation is proposed which is more robust when it faces with outlier points. We add weights to the one-to-one constraints, and modify them in the process of optimization in order to diminish the effect of outlier points in the matching procedure. We execute our proposed method on different real and synthetic databases to show both robustness and accuracy in contrast to several conventional GM methods
New methods of reducing the phase quantization error effects on beam pointing and parasitic side lobe level of the phased array antennas
, Article 2006 Asia-Pacific Microwave Conference, APMC, Yokohama, 12 December 2006 through 15 December 2006 ; Volume 3 , 2006 , Pages 2114-2117 ; 4902339102 (ISBN); 9784902339109 (ISBN) ; Farzaneh, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2006
Abstract
Usually the digital phase shifters are used to steer the beam of a phased array antenna, and the accuracy of beam steering and other properties of the radiation pattern is dependent on the number of bits of the phase shifter and its resolution. In this paper the results of simulations, accomplished using a number of phase feeding methods in order to reduce the phase quantization error effects are presented and three new methods are introduced and compared with the previous works. Copyright 2006 IEICE
Unsteady state work-roll temperature distribution during continuous hot slab rolling
, Article International Journal of Mechanical Sciences ; Volume 44, Issue 12 , 2002 , Pages 2447-2462 ; 00207403 (ISSN) ; Karimi Taheri, A ; Mucciardi, F ; Sharif University of Technology
2002
Abstract
Predicting temperature distributions in the work-rolls during the hot slab rolling process is of great importance to mill designers. This is because the temperature distribution and the dimensional accuracy of the slab being rolled are both dependent on the work-roll temperature. In addition, the life of the roll is also a function of its own temperature distribution. In this paper, the unsteady state heat transfer equations with time dependent boundary conditions are coupled with a two-dimensional finite element method to predict the work-roll temperature distribution during the continuous hot slab rolling process. To achieve an accurate temperature field, the effects of various factors...
Hydrogen separation through LSF-perovskite membrane prepared by chelating method
, Article Journal of Natural Gas Science and Engineering ; Volume 22 , January , 2015 , Pages 483-488 ; 18755100 (ISSN) ; Ghasemi, F ; Ganji Babakhani, E ; Taheri, Z ; Sharif University of Technology
Elsevier
2015
Abstract
La0.3Sr0.7FeO3-δ (LSF) perovskite was prepared according to two methods: (1) applying new phenolic derivative of serine amino acid (L) as chelating agent, and (2) in absence of L as ligand-free perovskite (LFP). The newly prepared aminophenolic ligand L was fully characterized by 1H and 13C NMR, IR as well as elemental analysis while the LSF perovskite samples were characterized using the IR spectra, powder x-ray diffraction (PXRD) patterns, and SEM micrographs. The PXRD pattern obtained for the perovskite prepared by L (PPP) indicated on the presence of pure perovskite phase. The hydrogen permeation through PPP and LFP membranes with thickness of 1.0mm were measured as a function of...
A simple and efficient synthesis of new indeno- and naphtho-fused thiophenes using arylthioacetamides
, Article Journal of Sulfur Chemistry ; Volume 27, Issue 6 , 2006 , Pages 545-552 ; 17415993 (ISSN) ; Saeidian, H ; Mirjafary, Z ; Taheri, S ; Sharif University of Technology
2006
Abstract
New indeno- and naphtho-fused thiophenes were synthesized from reaction of 2-bromo-1-indanone and 2-bromo-1-tetralone with arylthioacetamides in good yields
A study of timing side-channel attacks and countermeasures on javascript and webassembly
, Article ISeCure ; Volume 14, Issue 1 , 2022 , Pages 27-46 ; 20082045 (ISSN) ; Bayat Sarmadi, S ; Taheri Ardakani, F ; Sharif University of Technology
Iranian Society of Cryptology
2022
Abstract
Side-channel attacks are a group of powerful attacks in hardware security that exploit the deficiencies in the implementation of systems. Timing side-channel attacks are one of the main side-channel attack categories that use the time difference of running an operation in different states. Many powerful attacks can be classified into this type of attack, including cache attacks. The limitation of these attacks is the need to run the spy program on the victim’s system. Various studies have tried to overcome this limitation by implementing these attacks remotely on JavaScript and WebAssembly. This paper provides the first comprehensive evaluation of timing side-channel attacks on JavaScript...
Simulation of SO2 absorption in a venturi scrubber
, Article Chemical Engineering Communications ; Volume 197, Issue 7 , Feb , 2010 , Pages 934-952 ; 00986445 (ISSN) ; Mohebbi, A ; Taheri, A ; Sharif University of Technology
2010
Abstract
In this study, a three-dimensional mathematical model, based on a nonuniform droplet concentration distribution, has been developed to simulate gas absorption in a venturi scrubber. The mass transfer process was illustrated by assuming the liquid phase as a combination of droplets and film. The flow, just as the annular two-phase flow, includes a flow of liquid film layer on the walls and a flow of gas and liquid drops in the core. Peclet number was determined using experimental data reported by Viswanathan et al. (1984) for distribution of droplets across the cross section of the scrubber. The mathematical model for gas absorption was justified by comparing the theoretical predictions with...
Comparison of using formaldehyde and carboxy methyl chitosan in preparation of Fe3O4 superparamagnetic nanoparticles-chitosan hydrogel network: Sorption behavior toward bovine serum albumin
, Article Process Safety and Environmental Protection ; Volume 102 , 2016 , Pages 119-128 ; 09575820 (ISSN) ; Hanifpour, F ; Taheri, R ; Javadian, H ; Ghasemi, M ; Sharif University of Technology
Institution of Chemical Engineers
2016
Abstract
A novel and cost effective method of bio-separation developed recently is magnetic separation technology. In this study, super paramagnetic Fe3O4 nanoparticles are used for separation of bovine serum albumin (BSA) protein from plasma/serum samples at optimized conditions. The synthesis of chitosan hydrogel networks by two variant approaches that involve (1) crosslinking of chitosan with formaldehyde and (2) formation of carboxy methyl chitosan mediated complex, was investigated and the percent of gelation, swelling ratio and equilibrium water content were calculated. The results revealed the formation of better quality hydrogel from the first approach. In step 1, to quantify the BSA...
High-impact promotional effect of mo impregnation on aluminum-rich and Alkali-treated hierarchical zeolite catalysts on methanol aromatization
, Article ACS Omega ; Volume 5, Issue 21 , 2020 , Pages 11971-11986 ; Kazemi Zangeneh, F ; Taheri Rizi, Z ; Aghaei, E ; Sharif University of Technology
American Chemical Society
2020
Abstract
A systematic change of HZSM-5 (HZ5) as a catalyst of the methanol to aromatics (MTA) reaction was undertaken by employing a fixed-bed tubular-type reactor under ambient pressure, applying a weight hourly space velocity (WHSV) of 2 h-1 at 375 °C, as the first report on the application of low-Si/Al-ratio alkaline-[Mo,Na]-HZSM-5 in the MTA process. To characterize the surface and textural properties of the catalysts, powder X-ray diffraction (PXRD), nitrogen adsorption/desorption, temperature-programmed desorption of ammonia (NH3-TPD), pyridine-infrared spectroscopy (Py-IR), thermogravimetric analysis (TGA), and energy-dispersive X-ray (EDX) methods were employed. Gas chromatography (GC) and...
Optimizing structural and mechanical properties of coiled carbon nanotubes with nsga-ii and reactive molecular dynamics simulation
, Article Journal of Physical Chemistry C ; Volume 125, Issue 11 , 2021 , Pages 6237-6248 ; 19327447 (ISSN) ; Rangriz, F ; Karimi Taheri, A ; Abdi Jalebi, M ; Sharif University of Technology
American Chemical Society
2021
Abstract
Coiled carbon nanotubes (CCNTs) have increasingly become a vital factor in the new generation of nanodevices and energy-absorbing materials due to their outstanding properties. Here, the multiobjective optimization of CCNTs is applied to assess their mechanical properties. The best trade-off between conflicting mechanical properties (e.g., yield stress and yield strain) is demonstrated and the optimization of the geometry enables us to find the astonishing CCNTs with a stretchability of 400%. These structures have been recognized for the first time in the field. We derived several highly accurate analytical equations for the yield stress and yield strain by the implementation of...
Opposite trends of GAS6 and GAS6-AS expressions in breast cancer tissues
, Article Experimental and Molecular Pathology ; Volume 118 , 2021 ; 00144800 (ISSN) ; Hussen, B. M ; Taheri, F ; Sattari, A ; Yousefi, H ; Omrani, M. D ; Nazer, N ; Ghafouri Fard, S ; Taheri, M ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Growth arrest-specific gene 6 (GAS6) is a growth factor-like cytokine whose function is related with vitamin K. This protein interacts with receptor tyrosine kinase proteins such as Tyro3, Axl, and TAM Receptor family, therefore affecting the tumorigenic processes via different mechanisms. GAS6-antisense 1 (GAS6-AS1) is a long non-coding RNAs (lncRNAs) that is transcribed from a genomic regions nearby GAS6. This lncRNA is also implicated in the pathobiology of cancer. We intended to judge the role of GAS6 and GAS6-AS1 in the pathogenesis of breast cancer through appraisal of their expression levels in breast cancer tissues and their paired neighboring non-cancerous samples. Expression of...
Sol-gel derived hydroxyapatite coating on TiB 2/TiB/Ti substrate
, Article Surface Engineering ; Volume 28, Issue 7 , August , 2012 , Pages 526-531 ; 02670844 (ISSN) ; Dabir, F ; Taheri, M ; Sohrabi, N ; Toroghinejad, M. R ; Sharif University of Technology
2012
Abstract
The low erosion resistance of titanium and its alloys has prevented their widespread application as joint implants. In addition, one essential requirement for the implants to bond with the living bone is the formation of a bone-like apatite on their surfaces in the host body. To enhance the erosion resistance of the surface, a diffused layer of TiB2 was formed at 1000uC on the commercial pure titanium. Hydroxyapatite was then coated on the boronised titanium by means of dip coating in a sol-gel solution. In order to confirm the biocompatibility of the specimens, they were soaked in a simulated body fluid for several days. The surface morphology of the specimens after exposure was studied by...
The synthesis of dibenzazocines via tandem dinucleophilic addition of phenols to quinolinium salts
, Article Arkivoc ; Volume 2010, Issue 11 , Sep , 2010 , Pages 91-100 ; 1551-7012 (ISSN) ; Saeidian, H ; Kiamehr, M ; Mirjafary, Z ; Taheri, S ; Sharif University of Technology
Arkat
2010
Abstract
Dibenzazocines were prepared via tandem dinucleophilic addition of phenols to quinolinium salts in good yields. The procedure is efficient, simple and the substrates are easily available
Construction And Evaluation of Nickel Catalysts Based on Silica Structures to Apply in the Hydrogenation Process of Benzene
, M.Sc. Thesis Sharif University of Technology ; Khorashe, Farhad (Supervisor) ; Soltanali, Saeed (Supervisor) ; Mashaiekhi, Maryam (Co-Supervisor)
Abstract
Benzene is one of the most famous aromatic compounds characterized by ringing and stability, which is formed by both natural processes and human activities. Benzene is also a substance found in hydrocarbons such as gasoline and hexane. International organizations for cancer research and global health have identified benzene as a carcinogen. Also, polymer grade hexane and in fact the same benzene-free hexane is widely used in the petrochemical and lubrication industries (food industry) of the country, which also requires reducing benzene from 6 to 2% to less than 50% ppm. Since partial and selective hydrogenation of benzene is performed because it is a heterogeneous process, ie at the surface...
The effect of prestrain temperature on kinetics of static recrystallization, microstructure evolution, and mechanical properties of low carbon steel
, Article Journal of Materials Engineering and Performance ; Volume 27, Issue 5 , 2018 , Pages 2049-2059 ; 10599495 (ISSN) ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
In this research, the samples of a low carbon steel sheet were rolled up to a thickness prestrain of 67% at three different temperatures consisted of room, blue brittleness, and subzero temperature. Microhardness, SEM, and tensile tests were carried out to evaluate the static recrystallization kinetics defined by the Avrami equation, microstructural evolution, and mechanical properties. It was found that the Avrami exponent is altered with change in prestrain temperature and it achieves the value of 1 to 1. 5. Moreover, it was indicated that prestraining at subzero temperature followed by annealing at 600 °C leads to considerable enhancement in tensile properties and kinetics of static...
An investigation on tensile properties of coiled carbon nanotubes using molecular dynamics simulation
, Article Diamond and Related Materials ; Volume 74 , 2017 , Pages 154-163 ; 09259635 (ISSN) ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
A coiled carbon nanotube (CCNT) can be formed from the distortion of parent toroidal carbon nanotube with a uniform pitch length and a uniform spring rise angle. In this research molecular dynamics simulation was carried out to assess the tensile properties of three CCNT having indexes of (3,3), (4,4), and (5,5). The results indicated that Stone-Wales defects are necessary for thermodynamic stability of the CCNTs. The stress-strain curves showed that the yield stress, yield strain, and failure strain are decreased with increase in temperature. The force-displacement curves revealed that the spring constant of these materials is highly depended on the tube diameter and rising angle, while it...
Microstructural evolution, mechanical properties, and corrosion resistance of a heat-treated Mg alloy for the bio-medical application
, Article Journal of Magnesium and Alloys ; Volume 7, Issue 1 , 2019 , Pages 80-89 ; 22139567 (ISSN) ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
National Engg. Reaserch Center for Magnesium Alloys
2019
Abstract
During the recent years, some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical materials. In this work, the Mg–2Zn–1Gd–1Ca (wt%) alloy as a new metallic bio-material was produced by the casting process followed by the heat treatment. The samples of the alloy were solution treated at temperatures of 500, 550, and 600 °C and then quench aged at temperatures of 125, 150, and 175 °C. The results of SEM-EDS examinations indicated that the alloy microstructure consists of α-Mg matrix and the Ca2Mg6Zn3 and Mg3Gd2Zn3 secondary phases. With regard to the results of Vickers hardness test, the temperatures of 500 °C and 150 °C were selected...
Design and fabrication of a floating social robot: CeB the social blimp
, Article 13th International Conference on Social Robotics, ICSR 2021, 10 November 2021 through 13 November 2021 ; Volume 13086 LNAI , 2021 , Pages 660-670 ; 03029743 (ISSN) ; 9783030905248 (ISBN) ; Nemati, A ; Meghdari, A. F ; Ge, S. S ; Taheri, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Robotic blimps have a wide range of applications, such as monitoring activities in their surroundings, advertising, and performing on stages. They also have remarkable capacities to be used as a social robot. In this research, a manually operated social robotic blimp has been developed intending to interact with children as a social agent and attract adults’ attention as an entertainer in indoor public environments. Since the appearance of a social robot has a significant impact on its acceptance, first, we acquired opinions of several participants on the shape of a desired floating robot. The results revealed that a simple spherical structure adequately draws people’s attention. After...
A study of hyperelastic models for predicting the mechanical behavior of extensor apparatus
, Article Biomechanics and Modeling in Mechanobiology ; Volume 16, Issue 3 , 2017 , Pages 1077-1093 ; 16177959 (ISSN) ; Karimi Taheri, K ; Narooei, K ; Karimi Taheri, A ; Sharif University of Technology
Springer Verlag
2017
Abstract
In this research, the nonlinear elastic behavior of human extensor apparatus was investigated. To this goal, firstly the best material parameters of hyperelastic strain energy density functions consisting of the Mooney–Rivlin, Ogden, invariants, and general exponential models were derived for the simple tension experimental data. Due to the significance of stress response in other deformation modes of nonlinear models, the calculated parameters were used to study the pure shear and balance biaxial tension behavior of the extensor apparatus. The results indicated that the Mooney–Rivlin model predicts an unstable behavior in the balance biaxial deformation of the extensor apparatus, while the...