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Circuit Level Techniques for Soft Error Mitigation in Combinational and Sequential Parts in Nano-scale CMOS Technology
, Ph.D. Dissertation Sharif University of Technology ; Tabandeh, Mahmoud (Supervisor) ; Fazeli, Mahdi (Co-Advisor)
Abstract
CMOS technology has reached two digit nanometer dimensions. This scaling trend improves performance and power consumption on the one hand, and reduces noise margin and circuits reliability on the other. Along with downscaling, sensitivity to radiation induced soft errors is increasing. As CMOS dimensions are shrinking, node capacitance of circuits become smaller. Consequently, particles with smaller charge could induce parasitic voltages in some nodes and result in soft errors. There are more particles with smaller charge than the ones with larger. Therefore, soft error rate is rapidly increasing with technology advances. Single Event Multiple Effects (SEMEs) is a new challenge emerged in...
Evolution of sub-harmonic interfacial waves generated by a surface wave through a three-wave interaction
, Article Scientia Iranica ; Volume 19, Issue 2 , 2012 , Pages 225-233 ; 10263098 (ISSN) ; Jamali, M ; Sharif University of Technology
2012
Abstract
Higher-order effects in three-wave resonant interaction of a surface wave, with a pair of interfacial waves in a two-layer fluid, are studied theoretically. Following an initial rapid growth, the interfacial waves approach a steady state of constant amplitude. An explicit solution is presented for transition to the ultimate state of the interaction. It is shown that for interaction in a wave flume, it is necessary to include a 2nd pair of the interfacial waves, resulting from a reflection of the original pair in the analysis. The effects of different parameters on the dynamics of the interaction are investigated. The results indicate that a faster initial growth does not necessarily lead to...
Nurse Scheduling of an Emergency Department in Order to Decreasing Patients Waiting Time Using Simulation and Genetic Algorithm
, M.Sc. Thesis Sharif University of Technology ; Mahlooji, Hashem (Supervisor)
Abstract
This work attempt to analyze the impact of changes in nurse scheduling on quality of services at emergency department of Emam Khomeini Hospital Complex. In nurse scheduling some constraints such as maximum working hours per week and unacceptable working sequences must be considered. A simulation model is developed to cover the complete flow for the patient through the emergency department. Emergency department of Emam Khomeini is simulated in order to obtain the patient average waiting time for each nurse roster. Then a genetic algorithm is integrated with the simulation model. In each iteration genetic algorithm produces many nurse rosters . For each roster the patient average waiting time...
Synthesis and Characterization of Flexible Supercapacitors Based on Polymeric Hydrogel
, M.Sc. Thesis Sharif University of Technology ; Shojae, Akbar (Supervisor)
Abstract
Today, supercapacitors are an inseparable component of electronic devices such as hybrid cars, telecommunication equipment, and personal electronic devices, and this device is also used to store clean energy. In this research, polyacrylic acid hydrogel was first synthesized to be used as a supercapacitor electrode and polyaniline was used as an electrically conductive polymer in its structure to improve the electrical properties of this hydrogel. To achieve this structure, the previously synthesized polyacrylic acid hydrogel was immersed in a solution of aniline monomer and other components necessary for the aniline polymerization reaction, and after the soaking process was completed, the...
Doc2vec Natural Language Model of Farsi
, M.Sc. Thesis Sharif University of Technology ; Moghadasi, Reza (Supervisor)
Abstract
Due to immense increase in availability of text data, interest in using machine learning models to solve problems previously impossibly costly has increased significantly. The first step is to represent natural language in a form that is easy for the machine learning algorithms to work on. Recent advances in learned representation of text data using simple neural networks(e.g. word2vec and doc2vec) helped increase performance of natural language processing on downstream tasks. Here we show that methods like doc2vec that were examined mostly in the English language can be used on Persian(Farsi) with little modification. To Demonstrate this, we use text classification tasks, and train...
A survey on underwater wireless sensor networks routing algorithms
, Article 2017 IEEE 4th International Conference on Knowledge-Based Engineering and Innovation, KBEI 2017 ; Volume 2018-January , 2018 , Pages 0373-0378 ; 9781538626405 (ISBN) ; Nasehi Basharzad, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Considering their special features and numerous applications, sensor networks are noticed so much nowadays. A sub-group of these applications is underwater sensor networks, which encounter some challenges like reliable transportation, routing, MAC, positioning, limited bandwidth, high and variable propagation delay, defective underwater channels and low battery capacity. Acoustic technologies are a particular technology which can make strong underwater communications for Civilian and military applications. These networks are used in oceans for environmental monitoring, under sea discovery, unexpected events prevention, ships assisting, tactical monitoring and naval mine detection, but there...
Molecular dynamics simulation of plastic deformation and interfacial delamination of NiTi/Ag bilayer by cyclic-nanoindentation: Effects of crystallographic orientation of substrate
, Article Computational Materials Science ; Volume 168 , 2019 , Pages 229-245 ; 09270256 (ISSN) ; Sadrnezhaad, S. k ; Sharif University of Technology
Elsevier B.V
2019
Abstract
This paper presents a comparative study of plasticity and fracture behavior of the NiTi/Ag bilayer for the different crystallographic orientations of the substrate. Molecular dynamic (MD) simulation was used to determine the deformation mechanism, dislocation density, plastic energy dissipation and delamination of the NiTi/Ag bilayers near the interface, when NiTi aligned at (1 0 0), (1 1 1), (1 1 0), (3 2 1), (2 1 0) and (2 1 1) faces during the cyclic-nanoindentation test. The Griffith energy balance model was used to estimate the energy release associated with the delamination. The results of the simulation are suggested the dependence of deformation mechanism, energy release rate (Gin),...
A power efficient masking technique for design of robust embedded systems against SEUs and SETs
, Article 23rd IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems, DFT 2008, Boston, MA, 1 October 2008 through 3 October 2008 ; October , 2008 , Pages 193-201 ; 15505774 (ISSN) ; Miremadi, S. G ; Sharif University of Technology
2008
Abstract
In this paper, an SET and SEU tolerant latch suitable for use in embedded systems called SETUR (Single Event Transient and Upset Robust latch) is presented and evaluated. The SETUR is based on the use of a redundant feedback line and a CMOS delay element to tolerate the effect of the SETs occurring in the input line of the latch as well as SEUs occurring inside the latch. The experimental results show that the probability of an SET resulting in a soft error can be reduced up to 90% by choosing a proper delay value. The soft error rate of the SETUR due to SEUs occurring inside the latch is reduced by 95% while having lower area, power and performance overhead than the previously proposed...
Nonlinear Resonant Interaction of a Surface Wave and Interfacial Waves
, Ph.D. Dissertation Sharif University of Technology ; Jamali, Mirmosadegh (Supervisor)
Abstract
The results of a theoretical and experimental study of a resonant interaction between a surface wave and two internal waves are presented. It is shown that the motion of a surface wave in a horizontally infinite two-layer fluid can lead to generation of two oblique internal waves. The internal waves have short wave length compared to the surface wave and have nearly opposite propagation directions. The frequencies of the internal waves are approximately half of the frequency of the surface wave.
In present thesis, Higher-order effects in sub-harmonic resonant interaction of a surface wave with a pair of interfacial waves in a two-layer fluid are studied theoretically and experimentally....
In present thesis, Higher-order effects in sub-harmonic resonant interaction of a surface wave with a pair of interfacial waves in a two-layer fluid are studied theoretically and experimentally....
, Ph.D. Dissertation Sharif University of Technology ; Miremadi, Ghasem (Supervisor)
Abstract
In this thesis, we intend to propose low cost SED-tolerant techniques for different compo nents of embedded processors core including data path components such as register file and ALU as well as control path components such as control unit. Since the reliability es timation is the essential step in design of a fault-tolerant system, we propose fast and accu rate analytical soft error rate (SER) estimation techniques in Section 4. The proposed techniques have the ability to measure: 1) the SER of a design; 2) the SER of each indi vidual gate and FF, and 3) the SER of a specific path in the design. Using such infor mation, designers can selectively protect the vulnerable parts...
In this thesis, we intend to propose low cost SED-tolerant techniques for different compo nents of embedded processors core including data path components such as register file and ALU as well as control path components such as control unit. Since the reliability es timation is the essential step in design of a fault-tolerant system, we propose fast and accu rate analytical soft error rate (SER) estimation techniques in Section 4. The proposed techniques have the ability to measure: 1) the SER of a design; 2) the SER of each indi vidual gate and FF, and 3) the SER of a specific path in the design. Using such infor mation, designers can selectively protect the vulnerable parts...
Soft error rate estimation for combinational logic in presence of single event multiple transients
, Article Journal of Circuits, Systems and Computers ; Vol. 23, issue. 6 , 2014 ; Tabandeh, M ; Fazeli, M ; Sharif University of Technology
2014
Abstract
Fast and accurate estimation of soft error rate in VLSI circuits is an essential step in a soft error tolerant ASIC design. In order to have a cost effective protection against radiation effects in combinational logics, an accurate and fast method for identification of most susceptive gates and paths is needed. In this paper, an efficient, fast and accurate method for soft error propagation probability (SEPP) estimation is presented and its performance is evaluated. This method takes into account all three masking factors in multi cycles. It also considers multiple event transients as a new challenge in soft error tolerant VLSI circuit design. Compared with Monte Carlo (MC) simulation-based...
Low cost soft error hardened latch designs for nano-scale CMOS technology in presence of process variation
, Article Microelectronics Reliability ; Volume 53, Issue 6 , June , 2013 , Pages 912-924 ; 00262714 (ISSN) ; Tabandeh, M ; Fazeli, M ; Sharif University of Technology
2013
Abstract
In this paper, two Low cost and Soft Error Hardened latches (referred to as LSEH1 and LSEH2) are proposed and evaluated. The proposed latches are fully SEU immune, i.e. they are capable of tolerating all particle strikes to any of their nodes. Moreover, they can mask Single Event Transients (SETs) occurring in combinational logics and reaching the input of the latches. We have compared our SEU/SET-tolerant latches with some well-known previously proposed soft error tolerant latches. To evaluate the proposed latches, we have done a set of SPICE simulations. The simulation results trough comparisons with other hardened latches reveal that the proposed latches not only have more robustness but...
Single Event Multiple Upset (SEMU) tolerant latch designs in presence of process and temperature variations
, Article Journal of Circuits, Systems and Computers ; Volume 24, Issue 1 , January , 2015 ; 02181266 (ISSN) ; Tabandeh, M ; Fazeli, M ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2015
Abstract
In this paper, we propose two novel soft error tolerant latch circuits namely HRPU and HRUT. The proposed latches are both capable of fully tolerating single event upsets (SEUs). Also, they have the ability of enduring single event multiple upsets (SEMUs). Our simulation results show that, both of our HRPU and HRUT latches have higher robustness against SEMUs as compared with other recently proposed radiation hardened latches. We have also explored the effects of process and temperature variations on different design parameters such as delay and power consumption of our proposed latches and other leading SEU tolerant latches. Our simulation results also show that, compared with the reference...
An energy efficient circuit level technique to protect register file from MBUs and SETs in embedded processors
, Article Proceedings of the International Conference on Dependable Systems and Networks, 29 June 2009 through 2 July 2009, Lisbon ; 2009 , Pages 195-204 ; 9781424444212 (ISBN) ; Namazi, A ; Miremadi, S.G ; Sharif University of Technology
2009
Abstract
This paper presents a circuit level soft error-tolerant-technique, called RRC (Robust Register Caching), for the register file of embedded processors. The basic idea behind the RRC is to effectively cache the most vulnerable registers in a small highly robust register cache built by circuit level SEU and SET protected memory cells. To decide which cache entry should be replaced, the average number of read operations during a register ACE time is used as a criterion to judge. In fact, the victim cache entry is one which has the maximum read count. To minimize the power overhead of the RRC, the clock gating technique is efficiently exploited for the main register file resulting in...
Effect of copper content on tensile mechanical properties of ternary NiTiCu alloy nanowire: molecular dynamics simulation
, Article Materials Today: Proceedings ; Volume 5, Issue 1 , 2018 , Pages 1552-1555 ; 22147853 (ISSN) ; Vahedpour, M ; Sadrnezhaad, K ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Molecular dynamics (MD) simulation was used to study of mechanical properties of NiTiCu with different content of copper. It was shown that the percent composition of copper are significantly affects the stress-strain curves curve. The results showed that as the Cu content increased, the Yield Strength and Young's modulus decreased. © 2017 Elsevier Ltd
Preparation and characterization of starch-based composite films reinforced by cellulose nanofibers
, Article International Journal of Biological Macromolecules ; Volume 116 , 2018 , Pages 272-280 ; 01418130 (ISSN) ; Keley, M ; Biazar, E ; Sharif University of Technology
Elsevier B.V
2018
Abstract
The current study deals with the preparation and characterization of polysaccharide-based biocomposite films acquired by the incorporation of cellulose nanofiber within glycerol plasticized matrix formed by starch. The application of starch-based films is limited due to highly hydrophilic nature and poor mechanical properties. These problems are solved by forming a nanocomposite of thermoplastic starch (TPS) as matrix and cellulose nanofiber (CNF) as reinforcement. CNF is successfully prepared from short henequen fibers which consist of almost 60% cellulose by a chemo-mechanical process. TPS/CNF composite films are prepared by the polymer solution casting method, and their characterizations...
Identification of evolving interfacial waves by spatial harmonic analysis
, Article Environmental Fluid Mechanics ; Volume 17, Issue 4 , 2017 , Pages 647-664 ; 15677419 (ISSN) ; Safaie, A ; Jamali, M ; Sharif University of Technology
Springer Netherlands
2017
Abstract
This paper is concerned with an analysis of image processing data to identify interfacial waves at the interface between two fluid layers in a laboratory flume. The interfacial waves are excited through a non-linear resonant interaction with a surface wave traveling in a wave flume filled with a two-layer fluid. A spatial harmonic analysis is proposed to extract information about the nonlinear evolution of the constituent waves from the interface oscillation data. The analysis is capable of handling different stages of the resonance in the wave flume and gives accurate and consistent results on time variations of the wave amplitudes. Contrary to a temporal harmonic analysis, the proposed...
Design and simulation of an off-line internal navigation system for pipeline inspection applications
, Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 9 PART A , 2008 , Pages 521-526 ; 0791843033 (ISBN); 9780791843031 (ISBN) ; Nabi, A ; Fazeli, A ; Sharif University of Technology
2008
Abstract
The aim of this paper is to design an inertial navigation system (INS) for use in a geometry pipe inspection gauge, capable of measuring pipeline movements and producing the line's 3D map with a reasonable accuracy. A suitable reference path was generated as a design platform. Solving the navigation equations and compensating for the errors, by using extended Kaiman filter (EKF) approach, the INS path was generated and its position errors in all three directions were considered. Divergence problems due to far apart GPS position observations, was overcome by defining suitable threshold for the variances of the estimated errors. Copyright © 2007 by ASME
Computation of three-dimensional supersonic turbulent flows over wrap-around fin projectiles using personal computers
, Article Scientia Iranica ; Volume 12, Issue 2 , 2005 , Pages 217-228 ; 10263098 (ISSN) ; Azimi, A ; Farhanieh, B ; Sharif University of Technology
Sharif University of Technology
2005
Abstract
The three-dimensional supersonic turbulent flows over wrap-around fin missiles have been computed using the Thin Layer Navier-Stokes (TLNS) equations to reduce the computational efforts compared to those of the Full Navier-Stokes (FNS) equations. In this research, the missile configuration is divided into multi regions to enable fluid flow simulation using Personal Computers (PC). It also makes it possible to use a different number of nodes and distribution of grids in each region to enhance the accuracy. The Thin Layer Navier-Stokes equations in the generalized coordinate system were solved using an efficient, implicit, finite-difference factored algorithm of the Beam and Warming. For the...
Loss Reduction Feasibility Study in Distribution Network
, M.Sc. Thesis Sharif University of Technology ; Safaieh, Mohammad Reza (Supervisor)
Abstract
Regarding complexity and wide range use of distribution network structures, loss reduction is possible in case of complete knowledge and suitable approaches. Loss reduction not only can grow GDP but also can improve economic growth. It should have schedule and plan wisely. Thus, in this research, first a region called Yusef Abad in Tehran was selected then the network was assessed completely. During the assessment, the research team determines causes of energy loss and load loss and then measured amount of each one. Then, the loss share of each element of the network determined. Elements of the network consist of transformers, conductors and meters. Then possible solutions for loss reduction...