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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...
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...
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...
Passive primary/backup-based scheduling for simultaneous power and reliability management on heterogeneous embedded systems
, Article IEEE Transactions on Sustainable Computing ; 2022 , Pages 1-12 ; 23773782 (ISSN) ; Siyadatzadeh, R ; Ansari, M ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
In addition to meeting the real-time constraint, power/energy efficiency and high reliability are two vital objectives for real-time embedded systems. Recently, heterogeneous multicore systems have been considered an appropriate solution for achieving joint power/energy efficiency and high reliability. However, power/energy and reliability are two conflict requirements due to the inherent redundancy of fault-tolerance techniques. Also, because of the heterogeneity of the system, the execution of the tasks, especially real-time tasks, in the heterogeneous system is more complicated than the homogeneous system. The proposed method in this paper employs a passive primary/backup technique to...
Passive Primary/Backup-Based Scheduling for Simultaneous Power and Reliability Management on Heterogeneous Embedded Systems
, Article IEEE Transactions on Sustainable Computing ; Volume 8, Issue 1 , 2023 , Pages 82-93 ; 23773782 (ISSN) ; Siyadatzadeh, R ; Ansari, M ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In addition to meeting the real-time constraint, power/energy efficiency and high reliability are two vital objectives for real-time embedded systems. Recently, heterogeneous multicore systems have been considered an appropriate solution for achieving joint power/energy efficiency and high reliability. However, power/energy and reliability are two conflict requirements due to the inherent redundancy of fault-tolerance techniques. Also, because of the heterogeneity of the system, the execution of the tasks, especially real-time tasks, in the heterogeneous system is more complicated than the homogeneous system. The proposed method in this article employs a passive primary/backup technique to...
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. R ; 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...
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...
Effects of stabilizers on sustainability, activity and decolorization performance of Manganese Peroxidase enzyme produced by Phanerochaete chrysosporium
, Article Journal of Environmental Chemical Engineering ; Volume 8, Issue 6 , 2020 ; Zolfaghari, P ; Golizadeh, M ; Karimi, A ; Lau, A ; Ghiasi, B ; Ansari, Z ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Manganese Peroxidase (MnP), is one of the most promising lignin depolymerization enzymes, which has been widely used for degradation purposes. Nevertheless, MnP tends to lose activity rapidly during its maintenance phase and degradation process, especially in the inevitable presence of hydrogen peroxide. This study aimed to improve MnP efficiency produced by Phanerochaete chrysosporium, via enhancing its sustainability. In this context, the effects of MnO2, Fe3O4, PEG, Veratryl Alcohol (VA), and DMSO as stabilizing agents on MnP activity were explored both in vivo and in vitro. During in vivo experiments, heterogeneous Fe3O4 was found to be the desirable choice to enhance MnP production,...
A Comparative study of joint power and reliability management techniques in multicore embedded systems
, Article 3rd CSI/CPSSI International Symposium on Real-Time and Embedded Systems and Technologies, RTEST 2020, 10 June 2020 through 11 June 2020 ; 2020 ; Sahraee, A ; Saber Latibari, J ; Ansari, M ; Rohbani, N ; Ejlali, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Low power consumption and high-reliability are often major objectives in the design of embedded systems. To reduce power consumption, embedded systems usually employ system-level power management techniques, e.g. Dynamic Voltage Scaling (DVS) and Dynamic Power Management (DPM). To achieve high reliability, embedded systems often exploit fault-tolerant techniques. Fault-tolerant techniques are in a trade-off with energy consumption, peak-power consumption, and temperature. Thus, different methods have been introduced that simultaneously consider reliability and power consumption as the system constraints. Several novel methods have been proposed in previous works to reduce the power...
Optimization of supercritical carbon dioxide extraction of essential oil from spearmint (Mentha spicata L.) leaves by using Taguchi methodology
, Article Journal of Supercritical Fluids ; Volume 67 , July , 2012 , Pages 123-130 ; 08968446 (ISSN) ; Goodarznia, I ; Sharif University of Technology
2012
Abstract
In this study, the essential oil of aerial parts species of a plant called Spearmint was extracted by CO 2 to optimize the results of the supercritical extraction process. In order to achieve maximum total yield extraction and SF-CO 2 concentration, tests were done in a laboratorial pilot considering the Taguchi method under following condition: pressure. 90,100,140,170 bar, temperature. of 35, 40, 45, 50 °C, mean particles size: 250,500,710,1000 μm, flow rate 1,3,5,8 ml/s and dynamic time 30,50,90,120 min. The optimizing conditions for SCE and SF-CO 2 concentration are: 90 bar, 45 °C, 500 μm, 5 ml/s, 120 min and 90 bar, 35 °C, 250 μm, 1 ml/s, 30 min. SCE total yield and CO 2 concentration...