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Crosstalk Fault Treatment in NoCs Using Data Manipulation
, Ph.D. Dissertation Sharif University of Technology ; Miremadi, Ghasem (Supervisor)
Abstract
Recent advances in Very-Large-Scale Integration (VLSI) technologies have enabled designers to integrate a large number of Processing Elements (PEs) on a single die. According to International Technology Roadmap for Semiconductors (ITRS), the number of PEs will reach 5000 on a single die in 2021. Although the main achievements of such rapid advancement in chips are high processing speed, shrinkage of technology size has made chips highly sensitive to different challenges. Networks on chip (NoCs), as an example of these systems, are not exempted from these challenges. Crosstalk fault is one of the major fault resources in NoCs. Crosstalk faults occur due to coupling capacitances between...
, M.Sc. Thesis Sharif University of Technology ; Movahedi, Mojtaba (Supervisor)
Abstract
Martensitic stainless steels with high strength, good corrosion resistance and formability in the annealed condition are good choices for automotive applications, but they suffer from low weldability due to high hardenability and formation of brittle martensite without tempered structure in the weld metal and heat affected zone (HAZ). In other word, martensitic stainless steels have the worst weldability among all kinds of stainless steels. On the other hand, resistance spot welding is the main method for joining sheets in the automotive industry. Therefore, in the present work, microstructure and mechanical properties of the resistance spot welds of AISI 420 martensitic stainless steel in...
An efficient and low power one-lambda crosstalk avoidance code design for network on chips
, Article Microprocessors and Microsystems ; Volume 63 , 2018 , Pages 36-45 ; 01419331 (ISSN) ; Mahdavi, Z ; Sharif University of Technology
2018
Abstract
Crosstalk faults occurring in wires of Networks on Chip (NoCs) can seriously threaten the reliability of data transfer. One efficient way to tackle crosstalk faults is numeral-based Crosstalk Avoidance Codes (CACs). Numeral-based CACs reduce crosstalk faults by preventing specific transition patterns to occur. One-Lambda Codes (OLCs) are the most efficient types of CACs. However, the codec of OLCs imposes overheads including power consumption, critical path and area occupation to the routers of NoCs. To find overhead-efficient OLCs, this paper proposes an Algorithm for Generating OLC Numeral systems (AGON). AGON provides a tradeoff for designers in selecting overhead-efficient OLCs. Using...
Moral Particularism (Dancy's Version)
, M.Sc. Thesis Sharif University of Technology ; Miandari, Hassan (Supervisor)
Abstract
There are various versions of moral particularism, this dissertation deals with Jonathan Dancy's version of moral particularism. Dancy's particularism is a meta-ethical view maintains that the possibility of moral thought and judgment does not depend on the provision of a suitable supply of moral principles. This view is in contradiction to generalism. Dancy's particularism has two other main claims: there is no good reason to think that there is any suitable supply of moral principles, and moral principles, if there are any, are not useful. These claims are independent, but each of them depends on the doctrine of holism in the theory of reasons. This doctrine maintains that a feature that...
Crosstalk avoidance coding for reliable data transmission of network on chips
, Article 2013 International Symposium on System-on-Chip, SoC 2013 - Proceedings ; 2013 ; Miremadi, S. G ; Sharif University of Technology
2013
Abstract
Inter-wire coupling capacitance may lead to crosstalk faults that significantly limits the reliability of NoCs. In this paper, we propose a numerical-based crosstalk avoidance code that can omit the Triplet Opposite Direction (TOD) transitions produced by crosstalk faults. The proposed coding does not have ambiguity and uses all of the codeword space. Simulations using VHDL for different channel widths show that the proposed method can reduce crosstalk fault in the NoC links with negligible power and area overheads
Using binary-reflected gray coding for crosstalk mitigation of network on chip
, Article Proceedings - 17th CSI International Symposium on Computer Architecture and Digital Systems, CADS 2013 ; 2013 , Pages 81-86 ; 9781479905621 (ISBN) ; Miremadi, S. G ; Sharif University of Technology
IEEE Computer Society
2013
Abstract
This paper proposes an efficient crosstalk mitigation method for Network-on-Chips. This method uses the binary-reflected Gray coding to send the proper code word into a channel. As the Gray code has reflective and unit distance properties, based on these facts, content of every flit is selected so that to minimize the number of forbidden transition patterns in the channel. A VHDL-based simulation is carried out for several channel widths. Simulation results show that the proposed method reduces the forbidden transitions up to 26% and can save power in NoC links
On designing an efficient numerical-based forbidden pattern free crosstalk avoidance codec for reliable data transfer of NoCs
, Article Microelectronics Reliability ; Volume 63 , 2016 , Pages 304-313 ; 00262714 (ISSN) ; Miremadi, S. G ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Inter-wire coupling capacitances can lead to crosstalk fault that is strongly dependent on the transition patterns appearing on the wires. These transition patterns can cause mutual influences between adjacent wires of NoCs and as a result threaten the reliability of data transfer seriously. To increase the reliability of NoCs against the crosstalk fault, Forbidden Pattern Free (FPFs) codes are used. To generate FPF codes, numerical systems are among the overhead-efficient mechanisms. The algorithms of numerical systems have direct effect on the amounts of the codec overheads including power consumption, area occupation and performance of NoCs. To find an overhead-efficient numerical system,...
Simultaneous Fires Simulation in Two or Three Adjacent Tanks Using Computational Fluid Dynamic (CFD) Technique
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
In this thesis, behavior of multiple pool fires was investigated in the numerical method. Fire modeling is a complex process. The complexity intensify when simultaneous fires occurred, pool fire is the most likely among all kind of fires in city and industrial units. FDS software, a common CFD model for fire simulation, was used to simulate multiple pool fires. Using of CFD models is one of the most advanced techniques to fire simulation and FDS software have been used by engineers and researchers due to using of this technique. In the beginning, review of the existing investigations which FDS performance was examined of fire simulation is presented. Besides of the data gathering, in this...
Woman-Headed Household and Household Welfare An Emprical Study for Iran
,
M.Sc. Thesis
Sharif University of Technology
;
Suri, Davood
(Supervisor)
Abstract
This research aimed to investigate the relationship between household poverty and the gender of the head in the Iranian households. The self-reported gender of the head of household (FHH), underestimates the rate of poverty in female- head households (FHH). The self-reported gender of the head of household considers, conventionally, a family as male-head, even if the man of the family is incapable of making money. In much of these families the wife is the sole income holder even though she is not recognized as the head. In this study, a definition for household headship is introduced, which considers head of household the one who provides more than 50% of household income. Using household’s...
Simulation and Optimization of Ethane Recovery Unit Using Evolutionary Algorithms and Artificial Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Nowadays evolutionary algorithms help developers to solve many problems in applied science and engineering aspects. So the main goal of this thesis is to apply and verify the ability of evolutionary algorithms and artificial neural networks in optimization of Ethane recovery unit. Algorithms applied in this study are Ant Colony Algorithm, Artificial Immune Systems Algorithm, Incremental Evolutionary Algorithm, Chaotic Based Algorithm, Variable Population Size Genetic Algorithm, Frog Leaping Algorithm, Frog Leaping with Bacterial Optimization Approach and Different types of Particle Swarm Optimization Algorithm. Optimization methods based on local search are also applied in order to compare...
Layer of Protection Analysis (LOPA) for Nitroglycerine Production
,
M.Sc. Thesis
Sharif University of Technology
;
Rashtchian, Davood
(Supervisor)
Abstract
Nitroglycerine is an oily liquid and in pure form it is colorless. It is the main component of high explosives such as dynamites, and an essential ingredient of smokeless, double base propellants. The production of nitroglycerine has to solve the problems that arise from the extremely high mechanical sensitivity of the substance and the chemical instability of impure materials. Without sufficient control and mitigation of hazards, incidents have led to severe consequences, such as explosions, and threats to human lives, properties, and the environment. In this study, the hazard and operability study method is used to identify the existing hazards in the nitroglycerine production plant. Then,...
Risk Assessment of Probable Domino Scenarios Between Two Petrochemical Units
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Hazard analysis and risk assessment are the two significant methods of controlling and reducing risk caused by industrial units. To achieve the required safety needed in either new or operating plants, risk assessments are being used for some specific hazards such as fire, explosion and toxic release. Increasing industrial developments and occurrence of several catastrophic accidents in chemical processing plants have contributed to striking disasters and have obliged experts to use analytical solutions to evaluate frequencies and consequences of such events. Congested plants in industrial areas like Mahshahr and Asalouyeh in Iran and other places in the world are the reason why it has...
Modeling of Atmospheric Toxic Release and Dispersion Using CFD
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
In this project, ammonia dispersion in the environment have been investigated and the experimental data have been used in order to show accuracy of calculations. Also, the results of CFD have been compared with the results of PHAST software. The results show that when there is no obstacle in the way of gas release, dispersion models will get good results, but due to existence of the obstacle, their error will be increased to 300%. However, the error resulting from CFD is less than 24% even if there are obstacle there. The effects of obstacle’s distance and height on the dispersion of ammonia gas are investigated. This study showed that the concentration of ammonia increase, when the distance...
Optimum Process Unit Layout via Risk Assessment
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
One of the most important stages to designing a process plant is layout of equipment in unit area. There are plenty of routine procedures to find out equipment arrangement and their separation distances based on process and cost criteria. Although some studies have been carried out to enter safety parameters to conventional procedures, the problem complexity because of the number of involved equipment is still of concern. To clear these ambiguities, the new approach presented in this thesis is aimed at quantifying the effects of adjacent equipment on each other. In this way, fire radiation and explosion have been selected as the major hazard that any equipment can expose on the other items,...
Offering a Simple Method to Determine Safe Distance between Gas Pipelines and Vicinal Areas
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Sour Gas is more dangerous than sweet gas because of its hydrogen sulfide contents. So it requires more safety considerations. In this project, the effect of wall thickness and design factor of pipeline on the safe distance was examined by using risk assessment method. The safe distance tables for 4 pipelines with different wall thicknesses and design factors were prepared based on operating pressure, pipe diameter and hydrogen sulfide concentration in gas by using PHAST and PHAST RISK softwares. In this project, the depth of cover parameter was considered in safe distance determination. Also the leak of sour gas was simulated by using...
Iranian Household Saving Behavior
, M.Sc. Thesis Sharif University of Technology ; Souri, Davood (Supervisor)
Abstract
This paper decomposes the saving rate into cohort, age and year effects. This objective is accomplished by constructing a pseudo-panel that amalgamates nineteen consecutive, cross-sectional Household Income and Expenditure Surveys from 1991 to 2009. To construct year-of-birth cohorts with consistent composition over time, analyses are limited to those born between 1926 and 1975. Results reveal that those belonging to younger cohorts save a higher fraction of their income relative to their predecessors at the same age. Moreover, the increase in the saving rate can not be explained by the significant decline in household size or rise in educational attainment among younger cohorts. Closer...
Dispersion Modeling of Toxic Release (Chlorine) by CFD in Industrial and Urban Areas
,
M.Sc. Thesis
Sharif University of Technology
;
Rashtchian, Davood
(Supervisor)
Abstract
Chlorine is used in large quantities, in urban and industrial installations. Since chlorine is a toxic gas, its dispersion in such environments may have unpleasant consequences. On the point of Emergency Response Planning, it is important to know how such gases disperse. In this thesis, chlorine atmospheric dispersion is studied as an example of toxic dense gas dispersion. Chlorine accidental release from one of the storage tanks of Sohanak water refinery is selected for the case study. Laleh residential town is located in west of Sohanak refinery. According to the prevailing wind direction in Tehran (which is from the west to the east), the influence of the buildings of Laleh town on gas...
The Effect of Fence to Dilute the Dense Gas Dispersion Using CFD Model
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Release of toxic gases and hazardous materials is very dangerous for health of people that presence in near of release places. Whereas if the concentration of some toxic materials is more than a definite limit, it may cause of irreparable hurt to health of people in very short times, hence reduce the concentration of released materials can get the time for refuge in safe sites for people that presence in released site in initial times.
In this paper with use the Computational Fluid Dynamics models the effect of fence in reduce the concentration of dense gases and delay the distribution of these gases has been studied. The two toxic gas (chlorine and methyl-isocyanate ) have been...
In this paper with use the Computational Fluid Dynamics models the effect of fence in reduce the concentration of dense gases and delay the distribution of these gases has been studied. The two toxic gas (chlorine and methyl-isocyanate ) have been...
Process Modeling of Liquid-Ring Compressor for Flare Gas Recovery
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
The main application of flares is to protect facilities, staff, and surrounding area. Nevertheless, the flares flue gas contains environmental hazardous compounds like nitrogen oxides, sulfur oxides, and greenhouse gases like carbon dioxide and carbon monoxide. These compounds may spread in environment with unburned hydrocarbons. Due to the contamination risk and energy loss in flaring system, optimization and system enhancement is of vital importance. Flare gas recovery unit consist of equipment like multi-phase separator, Liquid Seal Drum, and compressor. The compressor is the most important part of this unit. Due to the process requirements and the probability of two-phase feed entering...
Dynamic Simulation of the Ammonia Tank Failure at Pardis Petrochemical Company
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Liquid ammonia atmospheric tank (20000 ton) attached to Pardis Petrochemical Complex was ruptured on 8th August 2011 due to overpressure blast injury so that ammonia gas was spread throughout the complex. The current study was aimed to evaluate ammonia leakage and emission from the tank. For this purpose, in addition to evaluate ammonia emission into the air, pressure changes were investigated to simulate the rupture. First of all, ammonia tanks and urea stocks were simulated and then considering two aerial classes (D and B), the incident was stimulated. According to this model, up to 1000 m, was contaminated with 1000 ppm of ammonia. Since there was no experimental data for validating the...