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Load Balancing in Network on-Chip
,
M.Sc. Thesis
Sharif University of Technology
;
Sarbazi Azad, Hamid
(Supervisor)
Abstract
This project presents a routing algorithm to cope with the dynamic traffic pattern of network-on-chip (NoC) architectures aiming to distribute the on-chip traffic evenly across the network. In this algorithm, instead of relying solely on local congestion information, the routes are determined based on the global information about on-chip traffic. This is achieved by employing a light-weight and efficient control network which monitors the on-chip traffic and collects the required information for determining the appropriate path between any pairs of communicating nodes in such a way that the congestion is avoided and the NoC load is balanced. Our experiments show that the proposed method...
Quantification of Seismic Performance Factors in Off-Center Bracing System(OBS) Equipped with Knee Element
, M.Sc. Thesis Sharif University of Technology ; Mofid, Masood (Supervisor)
Abstract
OBS Bracing System is a kind of concentric bracing frame that consists of three members and with y-shape layout can provide a necessary opening in the building. In this investigation will evalouate OBS Bracing System with Knee element. Buildings equipped with OBS-Knee bracing system considered SCBF. To design these buildings according to regulations, it is needed to have Seismic performance coefficients such as response modification factor (R), over strength factor (Ω0) and deflection amplification factor (Cd). The purpose of the present investigation is quantifying these parameters and evaluation of accuracy based on the proposed method in FEMA P695. In the mentioned method, at first by...
Decentralized control of reconfigurable robots using joint-torque sensing
, Article International Conference on Robotics and Mechatronics, ICROM 2015, 7 October 2015 through 9 October 2015 ; 2015 , Pages 581-585 ; 9781467372343 (ISBN) ; Sharif University of Technology
2015
Abstract
In this paper, a decentralized controller for trajectory tracking of modular and reconfigurable robot manipulators is developed. The proposed control scheme uses joint-torque sensory feedback; also sliding mode control is employed to make both position and velocity tracking errors of robot manipulators globally converging to zero. Proposed scheme also guarantees that all signals in closed-loop systems will be bounded. In contrast to some of prior works in this scheme, each controller uses a smooth law to achieve its purposes. In this method, each controller uses only local information for producing control law hence separated controller can be used to control each module of manipulator and...
Two new swinging interferometers
, Article Journal of Optics A: Pure and Applied Optics ; Volume 9, Issue 7 , 2007 , Pages 560-564 ; 14644258 (ISSN) ; Rashidian, B ; Sharif University of Technology
2007
Abstract
The most important disadvantage of swinging interferometers is that the optical path difference created in them is a nonlinear function of the rotation angle. In this paper, two new swinging interferometers are presented which have good linearity and provide a larger path difference in response to the rotation angle compared to other interferometers. This makes them suitable for applications such as high-resolution spectroscopy, and precision micro and nanopositioning. In one of these two interferometers, the optical path difference is created by rotation of a system composed of four mirrors, and in the other one it is created by rotation of a system consisting of two mirrors. They are not...
Numerical Investigation of Instabilities of Flow in Micro-fluid
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor)
Abstract
This research concerns investigating the behavior of two-phase flow in the inlet and outlet of the microchannels.Both the droplet based and the continuous microfluidics are considered. For the continuous system whenthe minor fluid enters the microchannel, due to ratio of viscosity of two fluids, viscous folding occurs.Viscous folding phenomena is similar to the buckling phenomena in solids.This means that the viscosity of the fluid, which is applied to two sides of the fluid layer, causes folding the fluid layer and changing the shape of it. For the study we employ a VOF based numerical routine. In order to verify numerical results, the grid and the time step independenciesare checked. In...
Comparison of Classic Regression Model and Geographically Weighted Regression Model in Trip Generation Models,Case Study in Shiraz
, M.Sc. Thesis Sharif University of Technology ; Kermanshah, Mohammad (Supervisor)
Abstract
Trip demand analysis is among the most important parts in comprehensive transportation studies. Developing four stage models including trip generation, trip distribution, mode choice, and assignment are so common in demand analyzing. In this study, trip generation models have been studied and to analyze data, two different methods including OLR and GWR are utilized. This study aims to examine relationship between aggregate zones in order to forecast future trips. Moreover, results of modeling trip generation with two different methods, OLR and GWR, are compared. Comparing different levels of aggregation reveals that as the number of zones decreases, the results get better. Decreasing number...
MBBR and MBR Reactor Configuration for Better Performance
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
Membrane bioreactors (MBRs) which are commonly understood as the combination of membrane filtration and biological treatment using activated sludge have several advantages, but membrane fouling reduces the membrane efficiency, permeability and lifetime. An alternative is replacing a moving bed biofilm reactor (MBBR) with the activated sludge system which may reduce the effect of membrane fouling. The sludge produced in MBBRs has poor settling characteristics, therefore, their efficiency is limited by the sedimentation tank performance and they require a larger settling surface. The combination of moving bed biofilm reactors and membrane bioreactors can compensate for the drawbacks of both of...
Improvement of palm oil and sunflower oil blends by enzymatic interestrification
, Article International Journal of Food Science and Technology ; Volume 46, Issue 5 , 2011 , Pages 1093-1099 ; 09505423 (ISSN) ; Alemzadeh, I ; Sharif University of Technology
2011
Abstract
Palm oil (PO) and sunflower oil (SFO) blends with varying proportions were subjected to enzymatic interesterification (EIE) using a 1,3-specific immobilised lipase. The interesterified blends were evaluated for their slip melting point (SMP), solid fat content (SFC) at 10-40°C, p-anisidine value, peroxide value, free fatty acids (FFA), induction period of oxidation at 110°C (IP110) and composition of fatty acids by gas chromatography. Under EIE treatment, the blends of PO and SFO in different proportions (20:80, 40:60, 50:50, 60:40 and 80:20) had saturated and unsaturated fatty acid content in the range of 37.6-52.0% and 48.0-62.4%, respectively. The blends showed a considerable reduction in...
Lipase catalyzed incorporation of conjugated linoleic acid by transesterification into sunflower oil applying immobilized lipase (Lipozyme TL IM and RM IM)
, Article International Journal of Engineering, Transactions A: Basics ; Volume 29, Issue 4 , 2016 , Pages 436-443 ; 17281431 (ISSN) ; Alemzadeh, I ; Sharif University of Technology
2016
Abstract
Conjugated Linoleic Acid (CLA), Glycerol (G) and sunflower oil blends with varying concentration were subjected to enzymatic esterification using a 1, 3-specific immobilized lipase. CLA was used as acyl due to its purported health benefits. The transesterified lipids were evaluated for free fatty acids (FFA) and composition of fatty acids by gas chromatography. Lipozyme RM IM is preferred for enzymatic esterification because of more CLA incorporation and less free fatty acids at the end of reaction than Lipozyme TL IM. Response surface methodology (RSM) was used to determine the effects of three variables Glycerol concentration, reaction temperature, and amount of enzyme on the lipase...
Prognostic of rolling element bearings based on early-stage developing faults
, Article International Journal of COMADEM ; Volume 23, Issue 1 , February , 2020 , Pages 55-60 ; Behzad, M ; Ghodrati, B ; Khodaygan, S
COMADEM International
2020
Abstract
Rolling-element bearing (REB) failure is one of the general damages in rotating machinery. In this manner, the correct prediction of remaining useful life (RUL) of REB is a crucial challenge to move forward the unwavering quality of the machines. One of the main difficulties in implementing data-driven methods for RUL prediction is to choose proper features that represent real damage progression. In this article, by using the outcomes of frequency analysis through the Envelope method, the initiated/existed defects on the ball bearings are identified. Also, new features based on developing faults of ball bearings is recommended to estimate RUL. Early-stage faults in ball bearings usually...
Stabilization of biped walking robot using the energy shaping method
, Article Journal of Computational and Nonlinear Dynamics ; Volume 3, Issue 4 , 2008 ; 15551423 (ISSN) ; Alasty, A ; Sharif University of Technology
2008
Abstract
The biped walking robot demonstrates a stable limit cycle on shallow slopes. In previous researches, this passive gait was shown to be sensitive to ground slope and initial conditions. In this paper, we discuss the feedback stabilization of a biped robot by the "energy shaping" technique. Two designs are proposed to reduce the sensitivity of the biped walking robot to slope and initial conditions. In the first design, a moving mass actuator is located on each link of the robot. The actuators are used to shape the potential energy of the biped robot so that it tracks the potential energy of a known passive gait of a similar biped robot on a different slope. Although the method is applied to a...
Mapping the spatiotemporal variability of salinity in the hypersaline Lake Urmia using Sentinel-2 and Landsat-8 imagery
, Article Journal of Hydrology ; Volume 595 , 2021 ; 00221694 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The spatiotemporal dynamic of salinity concentration (SC) in saline lakes is strongly dependent on the rate of water flow into the lake, water circulation, wind speed, evaporation rate, and the phenomenon of salt precipitation and dissolution. Although in-situ observations most reliably quantify water quality metrics, the spatiotemporal distribution of such data are typically limited and cannot be readily extrapolated for either long-term projections or extensive areas. Alternatively, remotely sensed imagery has facilitated less expensive and a stronger ability to estimate water quality over a wide range of spatiotemporal resolutions. This study introduces an adaptive learning model that...
Quantifying the uncertainty of lake-groundwater interaction using the forward uncertainty propagation framework: The case of Lake Urmia
, Article Journal of Hydrology ; Volume 610 , 2022 ; 00221694 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The interaction between a lake and groundwater has important implications to the quantity and quality of water in both environments. Quantification of lake-groundwater interaction (LGI) has been challenging in regions with limited in-situ data. LGI can be quantified by physically-based models, direct measurement of seepage, measurements of conservative chemical or isotopic tracers, and lake water balance. Despite the accuracy of the methods based on hydrochemical or isotopic measurements and analysis, they require extensive field data that are costly to collect in large lakes. Instead, the data required to quantify LGI by the lake water budget method can be obtained via typical ground...
Quantifying the impacts of agricultural alteration and climate change on the water cycle dynamics in a headwater catchment of Lake Urmia Basin
, Article Agricultural Water Management ; Volume 270 , 2022 ; 03783774 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The rapid shrinkage of Lake Urmia over the past two decades has raised serious environmental concerns. Several restoration plans have been proposed to reduce agricultural water consumption to supply a remarkable fraction of the lake's environmental flow requirement. However, an accurate and realistic evaluation of the effectiveness of these plans in reducing agricultural water consumption across the basin is still poorly understood. This study assessed the water-saving potential of agricultural alteration in a snow-dominated catchment in the Lake Urmia Basin. In particular, we explored the impact of crop pattern alteration via reducing the cultivation area and employing different irrigation...
Variable-complexity machine learning models for large-scale oil spill detection: the case of persian gulf
, Article Marine Pollution Bulletin ; Volume 195 , 2023 ; 0025326X (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
Oil spill is the main cause of marine pollution in the waterbodies with rich oil resources. In this study, we developed and compared the performance of variable-complexity machine-learning models to detect oil spill origin, extent, and movement over large scales. To this end, we trained Support Vector Machine (SVM), Random Forest (RF), and Convolutional Neural Network (CNN) models by using the statistical, geometrical, and textural features of Sentinel-1 SAR data. Our results in the Persian Gulf showed that CNN is superior to RF and SVM classifiers in oil spill detection, as evidenced by the testing accuracy of 95.8 %, 86.0 %, and 78.9 %, respectively. The results suggested utilizing both...
Spatiotemporal dynamics of chlorophyll-a in the Gorgan Bay and Miankaleh Peninsula biosphere reserve: Call for action
, Article Remote Sensing Applications: Society and Environment ; Volume 30 , 2023 ; 23529385 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2023
Abstract
Gorgan Bay (GB) and Miankaleh Peninsula biosphere reserve has faced an endangering condition because of a significant water loss and quality degradation due to intensive eutrophication. However, a synoptic view of the spatiotemporal dynamic of eutrophication is missing. In this study, we first used MODIS data to trace the long-term trend of eutrophication in GB between 2003 and 2021. To investigate the intra-annual variability of Chl-a in GB at a much higher spatial resolution, we developed an Artificial Neural Network (ANN) algorithm that uses Sentinel-2 imagery to map monthly Chl-a in the water year 2020–2021. Finally, we explored the major physical controls on eutrophication in GB....
Real Option Model for Selecting the Optimum Portfolio of Oil and Gas Projects and Determining the Optimal Time for Applying Real Option
, M.Sc. Thesis Sharif University of Technology ; Modarres Yazdi, Mohammad (Supervisor)
Abstract
Iran has the third largest reservoirs of oil and the second largest reservoirs of gas and has the greatest hydrocarbon reservoirs worldwide. Considering the fact that production of oil is highly dependent on gas injection, Iran is facing a great challenge in determining proper strategy for consuming natural gas. Due to the lack of proper strategy form the point of view of economical as well as scientific evaluation in political and social aspects, it has resulted in weakening Iran’s place in international markets and also reduction of oil wells’ productions.In this study, after a review of relevant literature, characteristics of oil and gas projects effective on modeling them were...
Forecasting the effects of a Canada-US currency union on output and prices: A counterfactual analysis
, Article Journal of Forecasting ; Volume 32, Issue 7 , 2013 , Pages 639-653 ; 02776693 (ISSN) ; Sharif University of Technology
2013
Abstract
This paper is a counterfactual analysis investigating the consequences of the formation of a currency union for Canada and the USA: whether outputs increase and prices decrease if these countries form a currency union. We use a two-country cointegrated model to conduct the counterfactual analysis, where the conditional forecasts are generated based on the Gaussian assumption. To deal with structural breaks and model uncertainty, conditional forecasts are generated from different models/estimation windows and the model-averaging technique is used to combine the forecasts. We also examine the robustness of our results to parameter uncertainty using the wild bootstrap method. The results show...
Fully supramolecular vesicles as anticancer drug delivery systems
, Article New Journal of Chemistry ; Volume 37, Issue 2 , 2013 , Pages 295-298 ; 11440546 (ISSN) ; Adeli, M ; Yazdi, M ; Sharif University of Technology
2013
Abstract
A supramolecular linear-dendritic copolymer consisting of a polystyrene backbone and hanging hyperbranched polyglycerols was prepared and characterized. Host-guest interactions between β-cyclodextrin incorporated in the core of polyglycerol as a host and aromatic rings of polystyrene as guests lead to the formation of a supramolecular linear-dendritic copolymer. Supramolecules formed micelles in aqueous solutions which were able to encapsulate and transfer paclitaxel with a high loading capacity
Modeling (r, Q) policy in a two-level supply chain system with fuzzy demand
, Article International Journal of Uncertainty, Fuzziness and Knowlege-Based Systems ; Volume 18, Issue 6 , 2010 , Pages 819-841 ; 02184885 (ISSN) ; Modarres Yazdi, M ; Sharif University of Technology
2010
Abstract
In this paper a two level supply chain system is studied, in which the final demand is assumed to be fuzzy with triangular membership function. The inventory control policy of (r, Q) is followed for this system and unsatisfied demand is assumed to be back ordered. The objective is to minimize the total cost of the system, including ordering, holding and shortage costs. The model happens to be a nonlinear programming. Considering the complexity arising from the model, we also develop a genetic algorithm to obtain a near-optimal solution. The method is illustrated through some numerical examples