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madjid-ansari--a
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Effects of short term and long term Extremely Low Frequency Magnetic Field on depressive disorder in mice: Involvement of nitric oxide pathway
, Article Life Sciences ; Volume 146 , 2016 , Pages 52-57 ; 00243205 (ISSN) ; Farzam Pour, S ; Sadr, A ; Shekarchi, B ; Majid Zadeh, A. K ; Sharif University of Technology
Elsevier Inc
2016
Abstract
Aims Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Main methods Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2 h and 2 weeks 2 h a day). Locomotor...
Empirical predictive model for generating synthetic non-stationary stochastic accelerogram of the Iranian plateau: including far- and near-field effects as well as mainshock and aftershock categorization
, Article Bulletin of Earthquake Engineering ; Volume 17, Issue 7 , 2019 , Pages 3681-3708 ; 1570761X (ISSN) ; Bakhshi, A ; Ansari, A ; Sharif University of Technology
Springer Netherlands
2019
Abstract
This work proposes comprehensive empirical predictive equations for generating stochastic synthetic 3-dimensional accelerograms for the Iranian plateau based on the existing database. First, the databank of Iranian accelerograms is collected, sorted, processed, declustered and categorized into the pulse-like and non-pulse-like data. To simulate the artificial accelerograms, a stochastic model capable of handling both the temporal and spectral non-stationarity of accelerograms is adopted. By implementing nonlinear curve fitting, parameters of the stochastic model are estimated. Then, the recorded events are categorized into eight distinct groups based on the existence of pulse-like...
Development of declustered processed earthquake accelerogram database for the Iranian Plateau: including near-field record categorization
, Article Journal of Seismology ; Volume 23, Issue 4 , 2019 , Pages 869-888 ; 13834649 (ISSN) ; Bakhshi, A ; Ansari, A ; Sharif University of Technology
Springer Netherlands
2019
Abstract
In this paper, a comprehensive accelerogram database of the Iranian plateau containing 3585 data with all three components is gathered. The raw data are processed by the wavelet-based denoising method, and results are compared with the contaminated data. All the data are classified into mainshock and aftershock categories using the time and spatial window method. Afterward, the data are categorized into the pulse-like and non-pulse-like events based on the detection of velocity pulse in any of horizontal and/or vertical directions. Eventually, among 3585 data, the ones with an average shear wave velocity of top 30 m of subsurface soil profile are selected and their important ground motion...
Design and Development of a Software for Analyzing Hydrodynamic Behavior of Spm System
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Madjid (Supervisor)
Abstract
In recent decades, SPM system has become a great method for transferring petroleum products to tankers and vice versa. SPM technology has shown his confidence and operation abilities. Sea waves are the most important phenomenon to be considered in the design of coastal and offshore structures. In this study dynamic motion of SPM floating structure is modeled under sea waves loading. Mooring lines connected to structure is modeled by using static stability equations and equivalent stiffness matrix is computed. First the SPM floating structure motion is modeled in 2 dimension (3 degree of freedom) using the boundary element method in frequency domain under regular sea waves loading and the...
Simulating Sediment Transportation (Scour) Under Pipelines
,
M.Sc. Thesis
Sharif University of Technology
;
Abbaspour, Madjid
(Supervisor)
Abstract
Regarding to significant role of marine pipelines in transferring oil, water and other products, a research was carried out to study the sediment transportation (Scouring) under pipelines which threaten pipelines. Interaction between fluid phase (flow field), structure phase (pipe) and sediment, determine scour profile shape and specifications of each phase which can change scour depth. In this research Flow-3D software was used to simulate scouring process under cylinder. First the flow field around cylinder near wall was studied and the scour depth under direct and oscillating flow was simulated. In addition, in next pace, the number of pipes and their distance were varied to measure...
Investigation on Hydrodynamic Locomotion of Sea Turtle
,
M.Sc. Thesis
Sharif University of Technology
;
Abbaspour, Madjid
(Supervisor)
Abstract
Nowadays, underwater vehicles designed by getting inspiration from aquatic animals’ motions have considerable merits; therefore, the issue of designing and building such vehicles has great significance. One of the aquatic animals, which can be a source of inspiration for designing vehicles with optimized propulsion and maneuver ability, is turtle. In order to design a robot under the inspiration of turtle locomotion, at first, it requires analyzing its locomotion carefully. In this project, it has been tried to do so. Having examined the motions of turtles and other aquatic animals thoroughly, the basics of their motions are achieved. Next, the locomotion of both sea and pond turtle are...
Design and Simulation of a Towed Underwater Vehicle
,
M.Sc. Thesis
Sharif University of Technology
;
Abbaspour, Madjid
(Supervisor)
Abstract
Nowadays marine-tourism industry, especially under water tourism, has become very attractive. Thus, numerous under water vehicles are designed and constructed. The primary objective of the present study is to design an underwater vehicle capable of carrying ten passengers. Tow system is proposed as propulsion system. Due to the high costs, noise and vibrations of existing propulsion systems in medium size vehicles which contradicts the goal of calm atmosphere for passenger, the proposing system seems suitable and pragmatic. Two-part tow system is utilized to enhance the stability of the under water vehicle named Towfish. In this study the structure of towfish is being designed. Then,...
Evaluation of the Hydrodynamic Performance of A Special Submarine Rescue System
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Madjid (Supervisor)
Abstract
The increasing growth of marine tourism has strengthened the activities related to this industry. One of the most profitable of these activities is recreational submarines. A traction recreational submarine is an idea in this field, in order to reduce costs, the propulsion force is removed and the submarine is towed by the mother ship. The most important reason for using the traction system and removing the independent drive is to prevent vibration and noise caused by the rotation of the propeller to prevent the escape of aquatic animals and to create a beautiful view from under the sea to watch underwater wonders. Searching for safety and saving people's lives in emergency situations is an...
Peak-power-aware energy management for periodic real-time applications
, Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Volume 39, Issue 4 , 2020 , Pages 779-788 ; Yeganeh Khaksar, A ; Safari, S ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Two main objectives in designing real-time embedded systems are high reliability and low power consumption. Hardware replication (e.g., standby-sparing) can provide high reliability while keeping the power consumption under control. In this paper, we consider a standby-sparing system where the main tasks on primary cores are scheduled by our proposed peak-power-aware earliest-deadline-first policy while the backup tasks on spare cores are scheduled by our proposed peak-power-aware earliest-deadline-late policy to meet the chip thermal design power (TDP) constraint. These policies provide the best opportunity to shift the task executions as much as possible to minimize execution overlaps...
A novel approach for the steady-state analysis of a three-phase self excited induction generator including series compensation
, Article ISIEA 2010 - 2010 IEEE Symposium on Industrial Electronics and Applications, 3 October 2010 through 5 October 2010, Penang ; 2010 , Pages 371-375 ; 9781424476473 (ISBN) ; Kashiha, A ; Ansari, K ; Sharif University of Technology
2010
Abstract
A new method to evaluate the steady state performance of a three-phase self excited induction generator based on conductance minimization is proposed. It can be simply used to take series compensation into account. Among the priorities of this method are the absence of convergence problem and flexibility. Simple methods to find the frequency and magnetizing reactance have been proposed. Simulation results show the efficiency of this method
Synthesis and characterization of CaO-P2O5-SiO2-Li2O-Fe2O3 bioactive glasses: The effect of Li2O-Fe2O3 content on the structure and in-vitro bioactivity
, Article Journal of Non-Crystalline Solids ; 2018 ; 00223093 (ISSN) ; Yazdanpanah, A ; Ansari Hamedani, A ; Ramedani, A ; Moztarzadeh, F ; Sharif University of Technology
Elsevier B.V
2018
Abstract
CaO-P2O5-SiO2-Li2O-Fe2O3 magnetic bioactive glasses were prepared through an optimized sol-gel method. This study was emphasized on the effects of magnetic content addition on the bioactive glass properties. As the need arises, we study synthesized magnetic bioactive glass physical, rheological, and biocompatible properties. The morphology and composition of these glasses were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The particle size was also determined using a laser particle size analyzer (LPSA). The thermal measurements were put through using Differential thermal analysis (DTA). In order to evaluate the...
Synthesis and characterization of CaO-P2O5-SiO2-Li2O-Fe2O3 bioactive glasses: The effect of Li2O-Fe2O3 content on the structure and in-vitro bioactivity
, Article Journal of Non-Crystalline Solids ; Volume 503-504 , 2019 , Pages 139-150 ; 00223093 (ISSN) ; Yazdanpanah, A ; Ansari Hamedani, A ; Ramedani, A ; Moztarzadeh, F ; Sharif University of Technology
Elsevier B.V
2019
Abstract
CaO-P2O5-SiO2-Li2O-Fe2O3 magnetic bioactive glasses were prepared through an optimized sol-gel method. This study was emphasized on the effects of magnetic content addition on the bioactive glass properties. As the need arises, we study synthesized magnetic bioactive glass physical, rheological, and biocompatible properties. The morphology and composition of these glasses were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The particle size was also determined using a laser particle size analyzer (LPSA). The thermal measurements were put through using Differential thermal analysis (DTA). In order to evaluate the...
Genomewide analysis of clp1 function in transcription in budding yeast
, Article Scientific Reports ; Volume 7, Issue 1 , 2017 ; 20452322 (ISSN) ; Sharifi, A ; Mousavi, S. A ; Chitsaz, H ; Ansari, A ; Sharif University of Technology
2017
Abstract
In budding yeast, the 3′ end processing of mRNA and the coupled termination of transcription by RNAPII requires the CF IA complex. We have earlier demonstrated a role for the Clp1 subunit of this complex in termination and promoter-associated transcription of CHA1. To assess the generality of the observed function of Clp1 in transcription, we tested the effect of Clp1 on transcription on a genomewide scale using the Global Run-On-Seq (GRO-Seq) approach. GRO-Seq analysis showed the polymerase reading through the termination signal in the downstream region of highly transcribed genes in a temperature-sensitive mutant of Clp1 at elevated temperature. No such terminator readthrough was observed...
Fracture analysis of monolayer graphene sheets with double vacancy defects via MD simulation
, Article Solid State Communications ; Volume 151, Issue 17 , 2011 , Pages 1141-1146 ; 00381098 (ISSN) ; Motevalli, B ; Montazeri, A ; Ajori, S ; Sharif University of Technology
2011
Abstract
Carbon nanostructures such as carbon nanotubes (CNTs) and graphene sheets have attracted great attention due to their exceptionally high strength and elastic strain. These extraordinary mechanical properties, however, can be affected by the presence of defects in their structures. When a material contains multiple defects, it is expected that the stress concentration of them superposes if the separation distances of the defects are low, which causes a more reduction of the strength. On the other hand, it is believed that if the defects are far enough such that their affected areas are distinct, their behavior is similar to a material with single defect. In this article, molecular dynamics...
The propagation of laser light in skin by Monte Carlo-diffusion method: A fast and accurate method to simulate photon migration in biological tissues
, Article Journal of Lasers in Medical Sciences ; Volume 2, Issue 3 , 2011 , Pages 109-114 ; 20089783 (ISSN) ; Tarei, M. G ; Ansari, M. A ; Amjadi, A ; Sharif University of Technology
2011
Abstract
Introduction: Due to the importance of laser light penetration and propagation in biological tissues, many researchers have proposed several numerical methods such as Monte Carlo, finite element and green function methods. Among them, the Monte Carlo method is an accurate method which can be applied for different tissues. However, because of its statistical nature, Monte Carlo simulation requires a large number of photon pockets to be traced, so it is computationally expensive and time-consuming. Although other numerical methods based on the diffusion method are fast, they have two important limitations: first, they are not valid near the bounder of sample and source, and second, their...
Peak power management to meet thermal design power in fault-tolerant embedded systems
, Article IEEE Transactions on Parallel and Distributed Systems ; Volume 30, Issue 1 , 1 January , 2019 , Page(s) 161 - 173 ; 10459219 (ISSN) ; Safari, S ; Khaksar, A. Y ; Salehi, M ; Ejlali, A ; Sharif University of Technology
IEEE Computer Society
2018
Abstract
Multicore platforms provide great opportunity for implementation of fault-tolerance techniques to achieve high reliability in real-time embedded systems. Passive redundancy is well-suited for multicore platforms and a well-established technique to tolerate transient and permanent faults. However, it incurs significant power overheads, which go wasted in fault-free execution scenarios. Meanwhile, due to the Thermal Design Power (TDP) constraint, in some cases it is not feasible to simultaneously power on all cores on a multicore platform. Since TDP is the maximum sustainable power that a chip can consume, violating TDP makes some cores automatically restart or significantly reduce their...
Peak power management to meet thermal design power in fault-tolerant embedded systems
, Article IEEE Transactions on Parallel and Distributed Systems ; Volume 30, Issue 1 , 2019 , Pages 161-173 ; 10459219 (ISSN) ; Safari, S ; Yeganeh Khaksar, A ; Salehi, M ; Ejlali, A ; Sharif University of Technology
IEEE Computer Society
2019
Abstract
Multicore platforms provide a great opportunity for implementation of fault-tolerance techniques to achieve high reliability in real-time embedded systems. Passive redundancy is well-suited for multicore platforms and a well-established technique to tolerate transient and permanent faults. However, it incurs significant power overheads, which go wasted in fault-free execution scenarios. Meanwhile, due to the Thermal Design Power (TDP) constraint, in some cases, it is not feasible to simultaneously power on all cores on a multicore platform. Since TDP is the maximum sustainable power that a chip can consume, violating TDP makes some cores automatically restart or significantly reduce their...
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Madjid (Supervisor)
Abstract
In order to design a ship with waterjet system, estimation of its hydrodynamic performance is crucial. Presence and operation of waterjet propulsion system changes the flow field and pressure distribution in bottom and stem of ship hull, so affect hydrodynamic performance of craft. In the present thesis, CFD analysis is applied to free surface flow around a waterjet propelled ship using ANSYS CFX software. Also a waterjet propulsion system is built and settled in a ship model and resistance and self propulsion tests are performed. In order to performing a systematic process in project, in the first step, pump design is performed with extracting optimum efficiency relations and cavitation...
Meeting thermal safe power in fault-tolerant heterogeneous embedded systems
, Article IEEE Embedded Systems Letters ; Volume 12, Issue 1 , 2020 , Pages 29-32 ; Pasandideh, M ; Saber Latibari, J ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Due to the system-level power constraints, it is encountered that not all cores in a multicore chip can be simultaneously powered-on at the highest voltage/frequency levels. Also, in the future technology nodes, reliability issues due to the susceptibility of systems to transient faults should be considered in multicore platforms. Therefore, two major objectives in designing multicore embedded systems are low energy/power consumption and high reliability. This letter presents an energy management system that optimizes the energy consumption such that it satisfies reliability target and meets timing, thermal design power (TDP) and thermal safe power (TSP) constraints. Toward the...
Simultaneous management of peak-power and reliability in heterogeneous multicore embedded systems
, Article IEEE Transactions on Parallel and Distributed Systems ; Volume 31, Issue 3 , 2020 , Pages 623-633 ; Saber Latibari, J ; Pasandideh, M ; Ejlali, A ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
Analysis of reliability, power, and performance at hardware and software levels due to heterogeneity is a crucial requirement for heterogeneous multicore embedded systems. Escalating power densities have led to thermal issues for heterogeneous multicore embedded systems. This paper proposes a peak-power-aware reliability management scheme to meet power constraints through distributing power density on the whole chip such that reliability targets are satisfied. In this paper, we consider peak power consumption as a system-level power constraint to prevent system failure. To balance the power consumption, we also employ a Dynamic Frequency Scaling (DFS) method to further reduce peak power...