Loading...
Search for:
arasteh--peyman
0.126 seconds
Calculating Runoff Coefficient of Urmia Lake Basin by Empirical Models and Remot Sensing (RS) Technology
, M.Sc. Thesis Sharif University of Technology ; Tajrishy, Masoud (Supervisor) ; Arasteh, Peyman (Co-Advisor)
Abstract
Estimation of runoff in the ungauged basins is a challenge for hydrologists. The main objective of this research is to produce runoff coefficient map using SCS-CN (1972) and Kennessey (1930) as empirical models to for Urmia Lake basin between for 2006-2011.Both SCS-CN and Kennessey methods use slope, land use, and soil permeability data to estimate surface runoff. Accuracy of each model is tested along with the observed runoff using the Root Mean Square Error (RMSE).Urmia Lake basin includes about 400,000 hectares irrigated land, which constitutes around 10 percent of the entire basin area. To exclude the anthropological activities from the estimations, methods were applied only for 28...
Disease Classification Based on Graph Learning using fMRI Datasets
, M.Sc. Thesis Sharif University of Technology ; Amini, Arash (Supervisor)
Abstract
In the past few years, the available knowledge in graph-based processing has made significant progress, and as a result, powerful tools have been created. In this regard, graph learning with the assumption of data smoothness on the final result can be considered a successful example. Briefly, in graph learning, to describe the relationship between the problem components, a graph is learned using the available data whose nodes represent the problem components, and its edges represent how much these components are connected. The usefulness of this method lies in the possibility of using the obtained graph as the input to currently known methods of classification and achieving better results...
Performance Ehancement of Congestion Control Algorithm Through Traffic Flow Istinction
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
Congestion is an important issue in the network environment. To keep stable the perfor-mance of the network, congestion control algorithms have been extensively studied. Queue management method employed by the routers is one of the important issues in the congestion control study. Active Queue Management (AQM) has been proposed for early detection of congestion inside the network. AQM mechanisms control the queue length in a router by dropping arriving packets. The Random Early Detection (RED) is the most popular AQM mechanism used in routers on the Intenet to allow network users to simultaneously achieve high throughput and low average delay. The RED algorithm may cause heavy oscillation of...
A Realistic Urban Mobility Model for Mobile Ad Hoc Network
, M.Sc. Thesis Sharif University of Technology ; Manzuri, Mohammad Taghi (Supervisor)
Abstract
A Mobile Ad hoc NETwork (MANET) is a set of wireless mobile nodes that form a self configured network. MANETs do not have infrastructure and are not currently deployed on large scales. So research in this area is simulation based. Mobility model in a mobile ad hoc network explains the movement pattern of mobile users and is designed to describe the change of their location, velocity and acceleration over time. One of the challenges in this field is the definition of a common mobility model that provides an accurate and realistic movement description of mobile nodes. In this thesis we want to study the mobility pattern of vehicles on Kish Island and compare it with different kinds of...
Multiple cell tracking algorithm assessment using simulation of spermatozoa movement
, Article 2015 IEEE 15th International Conference on Bioinformatics and Bioengineering, BIBE 2015, 2 November 2015 through 4 November 2015 ; 2015 ; 9781467379830 (ISBN) ; Vahdat, B. V ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
In this research, a web-based simulator is developed, which can be used for generating image sequences of moving spermatozoa cells. It can be used for assessment of multiple object tracking algorithms, especially Computer Aided Sperm Analysis (CASA) systems. The developed software has many useful parameters such as blurring images or adding noise and it also gives full control of sperm counts and types. To illustrate performance of the developed simulator, three parameters (spermatozoa population, standard deviation of Gaussian blur filter and noise intensity) have been swept and the results of three different multiple object tracking algorithms were compared as an application of this...
Calibrating priestley-taylor model to estimate open water evaporation under regional advection using volume balance method-case study: chahnimeh reservoir, Iran
, Article Journal of Applied Sciences ; Volume 8, Issue 22 , 2008 , Pages 4097-4104 ; 18125654 (ISSN) ; Tajrishy, M ; Sharif University of Technology
2008
Abstract
The objective of this study is to calibrate Priestley-Taylor (PT) model for estimating open water evaporation from an arid region reservoir called Chahnimeh. Chahnimeh Reservoir which is situated in the Sistan area in the southeast of Iran is being affected by regional energy advection during May to October. Therefore, common models of open water evaporation estimation such as PT require calibration. PT method was calibrated for Chahnimeh Reservoir using a volume balance method. Results showed that PT coefficient, αPT, as a constant over the year varies between 2.47±0.09 and 1.20±0.03 for two different hydrologic conditions of dry and wet. It means that there is also an intra-annular...
A trust and reputation-based access control model for virtual organizations
, Article 2012 9th International ISC Conference on Information Security and Cryptology, ISCISC 2012, 13 September 02012 through 14 September 2012 ; September , 2012 , Pages 121-127 ; 9781467323864 (ISBN) ; Amini, M ; Jalili, R ; Sharif University of Technology
2012
Abstract
Virtual organization (VO) is aimed to provide inter-organizational collaborations. Constructing a VO necessitates provision of security and access control requirements which cannot be satisfied using the traditional access control models. This is basically due to special features of VOs; such as temporality, unknown users, and diverse resources. In this paper, after expressing our assumption on a framework for VOs; the concept of organizational trust and reputation is used to establish an access control model for VOs. Each member of an organization inherits its organizational reputation. Resource providers announce the behavior of their interacting users to their organization manager....
A new method for infill equivalent strut width
, Article Structural Engineering and Mechanics ; Volume 69, Issue 3 , 2019 , Pages 257-268 ; 12254568 (ISSN) ; Mahdipour Arasteh, A ; Sharif University of Technology
Techno Press
2019
Abstract
Infills are as important members in structural design as beams, columns and braces. They have significant effect on structural behavior. Because of lots of variables in infills like material non-linear behavior, the interaction between frames and infill, etc., the infills performance during an earthquake is complicated, so have led designers do not consider the effect of infills in designing the structure. However, the experimental studies revealed that the infills have the remarkable effect on structure behavior. As if these effects ignored, it might occur soft-story phenomena, torsion or short-column effects on the structures. One simple and appropriate method for considering the infills...
A novel method based on empirical mode decomposition for P300-Based detection of deception
, Article IEEE Transactions on Information Forensics and Security ; Volume 11, Issue 11 , 2016 , Pages 2584-2593 ; 15566013 (ISSN) ; Moradi, M. H ; Janghorbani, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Conventional polygraphy has several alternatives and one of them is P300-based guilty knowledge test. The purpose of this paper is to apply a new method called empirical mode decomposition (EMD) to extract features from electroencephalogram (EEG) signal. EMD is an appropriate tool to deal with the nonlinear and nonstationary nature of EEG. In the previous studies on the same data set, some morphological, frequency, and wavelet features were extracted only from Pz channel, and used for the detection of guilty and innocent subjects. In this paper, an EMD-based feature extraction was done on EEG recorded signal. Features were extracted from all three recorded channels (Pz, Cz, and Fz) for...
Attenuation and Scatter Correction in Whole Body Positron Emission Tomography Images using Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Abolfazl (Supervisor) ; Sheikhzadeh, Peyman (Co-Supervisor)
Abstract
Objective: Accurate quantification in PET imaging is essential for proper evaluation and requires attenuation and scatter correction. Typically, this correction is performed using CT; however, the propagation of CT image errors to PET, the additional radiation dose in PET/CT, especially in pediatric cases and repeated scans, as well as challenges associated with standalone PET and PET/MRI, highlight the need for alternative approaches. This study investigates the capability of deep learning in jointly correcting attenuation and scatter for PET images with different radiotracers. Methods: Various neural network models, including ResNet, U-Net, and swin UNETR, were trained for direct...
Developing inherently resilient software against soft-errors based on algorithm level inherent features
, Article Journal of Electronic Testing: Theory and Applications (JETTA) ; Vol. 30, issue. 2 , 2014 , p. 193-212 ; Miremadi, S. G ; Rahmani, A. M ; Sharif University of Technology
2014
Abstract
A potential peculiarity of software systems is that a large number of soft-errors are inherently derated (masked) at the software level. The rate of error-deration may depend on the type of algorithms and data structures used in the software. This paper investigates the effects of the underlying algorithms of programs on the rate of error-deration. Eight different benchmark programs were used in the study; each of them was implemented by four different algorithms, i.e. divide-and-conquer, dynamic, backtracking and branch-and-bound. About 10,000 errors were injected into each program in order to quantify and analyze the error-derating capabilities of different algorithm-designing- techniques....
Effect of Y2O3 and Er2O3 co-dopants on phase stabilization of bismuth oxide
, Article Ceramics International ; Volume 37, Issue 8 , 2011 , Pages 3451-3455 ; 02728842 (ISSN) ; Maghsoudipour, A ; Alizadeh, M ; Nemati, A ; Sharif University of Technology
2011
Abstract
Bi2O3 compositions were prepared to investigate the effect of rare earth metal oxides as co-dopants on phase stability of bismuth oxide. Compositions containing 9-14 mol% of Y2O3 and Er2O3 were synthesized by solid state reaction. The structural characterization was carried out using X-ray powder diffraction. The XRD results show that the samples containing 12 and 14 mol% total dopants had cubic structure, whereas the samples with lower dopant concentrations were tetragonal. Comparing the lattice parameters of the cubic phases of (Bi 2O3)0.88(Y2O3) 0.06(Er2O3)0.06 and (Bi 2O3)0.86(Y2O3) 0.07(Er2O3)0.07 revealed that lattice parameter decreases by increasing the dopant concentration. The XRD...
Multi-Target tracking of human spermatozoa in phase-contrast microscopy image sequences using a hybrid dynamic bayesian network
, Article Scientific Reports ; Volume 8, Issue 1 , 2018 ; 20452322 (ISSN) ; Vosoughi Vahdat, B ; Salman Yazdi, R ; Sharif University of Technology
Nature Publishing Group
2018
Abstract
Male infertility is mostly related to semen and spermatozoa, and any diagnosis or treatment requires the investigation of the motility patterns of spermatozoa. The movements of spermatozoa are fast and involve collision and occlusion with each other. In order to extract the motility patterns of spermatozoa, multi-target tracking (MTT) of spermatozoa is necessary. One of the most important steps of MTT is data association, in which the newly arrived observations are used to update the previous tracks. Dynamic Bayesian network (DBN) is a powerful tool for modeling and solving various types of problems such as tracking and classification. There can also be a hybrid-DBN (HDBN), in which both...
Vapor Assisted Solution Processing of Multi-cation Perovskites as the Absorber of Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima (Supervisor)
Abstract
In this research, we fabricated and characterized hybrid organic-inorganic perovskite solar. The purpose of this study was the fabrication of multi-cationic perovskite films with vapor-assisted solution process, which was carried out in two different atmospheric and low-pressure conditions. In this regard, the reference cells with CH3NH3PbI3 and HC(NH2)2PbI3 compositions were made, which yielded 15.2% and 7.19% efficiencies in atmospheric conditions, and 6.38% and 2.65% in low pressure conditions, respectively. To increase the stability and to improve cell device performance, Br anion was added to the CH3NH3PbI3 structure. In optimum conditions, the conversion efficiency was 12.18%. Further...
Role of information technology in business revolution
, Article International Journal of Advanced Manufacturing Technology ; Volume 53, Issue 1-4 , 2011 , Pages 411-420 ; 02683768 (ISSN) ; Aliahmadi, A ; Mahmoodi, H.S ; Mohammadpour, M. O ; Sharif University of Technology
2011
Abstract
This paper investigates the relation between information technology (IT) and the change of business operations. We evaluate the geographical demand of companies for customer service interactions. The structure is a separate selection model in which districts play the role of distinguished products. The approximated demand structure is used to evaluate the results of IT on customer size, place selection, and cost preserving. The results verify the higher cost vulnerability of IT-thorough companies but propose that capability to utilize cost different is highly company-specified and that the influence of geographically restricted externalities is even existent. Because the productivity of many...
Hydrodynamic Interactions of Artificial Reef using a Laboratory Model
,
M.Sc. Thesis
Sharif University of Technology
;
Borghei, Mahmoud
(Supervisor)
;
Aghtouman, Peyman
(Supervisor)
Abstract
Resources management is essential duo to sustainable development and marine resources limitations. There are several ways to restore coastal damaged ecosystems, one of the best and most cost effective solution is establishment of artificial reefs. A popular type of artificial reef is named Reef ball, a hollow hemisphere. In some regions these habitats has also been used as submerged breakwater. These structures recover and protect endangered species ecosystem although they provide aesthetic view to a beach. Main application of these structures is to provide a safe environment for marine creature. In this study initially Transmission coefficient variation in two-dimensional model experiments...
Using genetic algorithm to identify soft-error derating blocks of an application program
, Article Proceedings - 15th Euromicro Conference on Digital System Design, DSD 2012, 5 September 2012 through 8 September 2012 ; September , 2012 , Pages 359-367 ; 9780769547985 (ISBN) ; Rahmani, A. M ; Mansoor, A ; Miremadi, S. G ; Sharif University of Technology
2012
Abstract
Soft-errors are increasingly considered as a major cause for computer system failures. Software techniques are used as cost-effective and flexible techniques to tolerate soft-errors but the introduced overhead is not acceptable in some safety-critical real-time systems. The identification of the program blocks and protecting only vulnerable blocks against soft-errors reduces the performance overhead. In this paper, we present a genetic algorithm to identify the vulnerable program blocks as well as the derating program blocks against soft-errors. Then, only vulnerable blocks are protected by some software-based soft-error tolerance techniques to achieve a lower performance and space overhead....
Lateral solutions for optimizing holding costs in job shops
, Article International Journal of Advanced Manufacturing Technology ; Volume 56, Issue 1-4 , 2011 , Pages 261-272 ; 02683768 (ISSN) ; Aliahmadi, A ; Sefidkoohi, H. M ; Omran, M. M ; Sharif University of Technology
2011
Abstract
Queuing networks present as beneficial models for a category of problems emerging in modern manufacturing systems. As the optimal control problem for queuing networks in familiar to be difficult, an important topic of research during the last two decades has been the growth of difficult estimations, and the use of these estimations to control optimal controls. Flexible moderations are an important class of such estimations that have received much consideration in recent years. The central objective of this paper is to determine the utilization of flexible moderations in solving a diversity of scheduling problems. In this paper, we investigate the role of flexible moderations in solving...
Improvment of Plant Availabilty Through Failure Prioritization Approach
, M.Sc. Thesis Sharif University of Technology ; Ghodrati, Behzad (Supervisor)
Abstract
In order to survive in the competitive market, companies should increase the availability of plants. In order to increase the availability of a system, the occurrence of failures should be decreased. It is not possible to eliminate all of failures simultaneously. It means, it is not cost effective and logical to concentrate on elimination of all failures. In Addition, the cause of some failures might not be eliminated. So, the occurrence of those failures should be postponed to the later time as much as possible. Therefore, the critical failure modes should be identified to be concentrated for further analysis. Ultimately; the root causes of these failures should be explored and if it is...
Using Compartment Modeling for the Non-Invasive Diagnosis of Malignant Tumors, as Well as Determining the Active Volume and Total Glycolysis of Malignant Tumors in PET/CT Imaging with FDG Radiation
, Ph.D. Dissertation Sharif University of Technology ; Hosseini, Abolfazl (Supervisor) ; Sheikhzadeh, Peyman (Co-Supervisor)
Abstract
In static PET/CT imaging, the Standardized Uptake Value (SUV) parameter is used to evaluate diseases. The use of this parameter provides valuable information to physicians in many cases. However, this parameter has limitations and is not suitable for certain clinical applications, such as assessing treatment response and differentiating between benign and malignant tumors. In contrast, utilizing dynamic imaging systems can yield significant information through the extraction of kinetic features and quantitative analysis based on temporal data. However, the use of dynamic PET imaging in a clinical setting can be challenging due to factors such as prolonged scan times (> 60 minutes),...