Loading...
Search for:
kaviani--alireza
0.117 seconds
Total 549 records
An Estimation of The Amount of Rent in The Economy of Iran (As an Oil Economy)
,
M.Sc. Thesis
Sharif University of Technology
;
Nili, Massoud
(Supervisor)
Abstract
The main objective of this research is to provide an estimation of the amount of rent in Iran as an oil economy. First by reviewing recent studies, the concept of rent was extracted and the rent measuring indexes were assessed. Having considered the four categories of rent in Iran, budgetary rent, interest rent, import rent and energy rent, the amount of rent in Iran’s economy during (1369:1-1386:4) was estimated. Results show a considerable increase of rent during (1369:1-1372:4) & (1384:1-1386:4). In the next section of this study the long run and short run relationship between rent and some of the macro economic variables was estimated.In this section the co-movement of rent trend with...
Localization of Active Aerial Targets Using Targets with Known Location
, M.Sc. Thesis Sharif University of Technology ; Behnia, Feridoon (Supervisor)
Abstract
Localization of radio, acoustic and vibration wave’s sources by passive systems has many applications in positioning systems, navigation systems, wireless sensor networks, defense, security, and geophysics. RSS, AOA, TDOA, and FDOA are some of the techniques available for passive localization. The performance of TDOA/FDOA techniques does not degrade with distance and multipath, but it may suffer from poor performance for narrowband signals. On the other hand, FDOA technique requires narrowband signals. Thus, the combination of TDOA and FDOA can be suitable for a much wider range of sources. In addition, the TDOA/FDOA method can provide more accurate interference source localization compared...
Flow and Heat Transfer between Two Cylinders with Internal Rotation
, M.Sc. Thesis Sharif University of Technology ; Noori Boroujerdi, Ali (Supervisor)
Abstract
The objective of this project is numerical simulation of air flow and heat transfer between two horizontal concentric cylinders with rotation of inner cylinder and inertia of outer cylinder grooves on the inner cylinder. In this study, the air, meanwhile rotational motion by the inner cylinder will enter into the annular space between two cylinders with certain flow rate. It can be mentioned to cooling of power plant generators, Electric motors and rotating machines among usages of air flow between two cylinders. In this article the objective is calculation of pressure drop and Nusselt number, temperature distribution on the inner cylinder under conditions of constant temperature of...
A new method for traffic density estimation based on topic model
, Article Signal Processing and Intelligent Systems Conference, 16 December 2015 through 17 December 2015 ; 2015 , Pages 114-118 ; 9781509001392 (ISBN) ; Ahmadi, P ; Gholampour, I ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Traffic density estimation plays an integral role in intelligent transportation systems (ITS), using which provides important information for signal control and effective traffic management. In this paper, we present a new framework for traffic density estimation based on topic model, which is an unsupervised model. This framework uses a set of visual features without any need to individual vehicle detection and tracking, and discovers the motion patterns automatically in traffic scenes by using topic model. Then, likelihood value allocated to each video clip enables us to estimate its traffic density. Results on a standard dataset show high classification performance of our proposed...
Frictional viscoelastic based model for spherical particles collision
, Article Granular Matter ; Volume 20, Issue 4 , 2018 ; 14345021 (ISSN) ; Nejat Pishkenari, H ; Sharif University of Technology
Springer New York LLC
2018
Abstract
In this paper, collision of two balls in three dimensions with regard to energy loss and friction is studied. This investigation intends to propose the procedure which can determine the condition of pure sliding, sliding with rolling or sticking, and rolling or sticking at the beginning of contact. Furthermore, the other aim of this research is to suggest the closed-form relation for post-collision angular and linear velocities in which the possibility of three regimes of impact, pure sliding, sliding with rolling, and pure rolling, are considered. In this investigation, viscous Hertz contact force describes the normal interaction force. Moreover, stick regime is not taken into account and...
Visual Event Recognition and Description
, M.Sc. Thesis Sharif University of Technology ; Gholampour, Iman (Supervisor) ; Tabandeh, Mahmoud (Supervisor)
Abstract
Increasing needs for traffic video surveillance and intelligent video analysis is a hot topic that has attracted significant interests in recent days. Scene understanding is one of the most important aspects of an intelligent video surveillance system. Statistics shows that rate of vehicle accidents has been continuously increasing over the past years. This necessitates the need for efficient traffic analysis and abnormality detection systems. It is desirable to develop fully automated surveillance systems, with which people will be free from boring monitoring tasks. In this thesis our goal is to describe and detect abnormal event like accident or variation of traffic density in traffic...
Development of Integrated Navigation Algorithm Based on the Integration of INS, GPS, Altimeter Using Particle Filters
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Alasti, Aria (Supervisor)
Abstract
Over the past years, several approaches have been used for navigation. Along with the advancement of technology, complicated navigation systems such as inertial navigation system and global positioning system have been employed. These navigation systems have their own strengths and weaknesses. To improve overall system performance they are integrated together as one system.
Presented research aims at developing the integrated navigation system through particle filters. In this study, after a brief overview of the data integration techniques, several techniques which are more common and have better performance than others are examined. This contribution concentrates on filtering methods...
Presented research aims at developing the integrated navigation system through particle filters. In this study, after a brief overview of the data integration techniques, several techniques which are more common and have better performance than others are examined. This contribution concentrates on filtering methods...
Comparison of nonlinear filtering techniques for inertial sensors error identification in INS/GPS integration
, Article Scientia Iranica ; Volume 25, Issue 3B , 2018 , Pages 1281-1295 ; 10263098 (ISSN) ; Salarieh, H ; Alasty, A ; Abediny, M ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
Nonlinear filtering techniques are used to fuse the Global Positioning System (GPS) with Inertial Navigation System (INS) to provide a robust and reliable navigation system with a performance superior to that of either INS or GPS alone. Prominent nonlinear estimators in this field are Kalman Filters (KF) and Particle Filters (PF). The main objective of this research is the comparative study of the well-established filtering methods of EKF, UKF, and PF based on EKF and UKF in an INS-GPS integrated navigation system. Different features of INS-GPS integrated navigation methods in the state estimation, bias estimation, and bias/scale factor estimation are investigated using these four filtering...
Design of a Tester for GOOSE Messages Performance Testing Defined in IEC 61850
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
Nowadays, electrical energy is a necessity and the use of intelligent power equipment is expanding. Of course, having a protocol for communicating between such equipment is not only useful but sometimes mandatory. In the past, each equipment manufacturer used its own method for communication, hence, the "IEC 61850" standard was proposed as a solution to solve the problem of communication between different equipment. In this research, we intend to design a tester to perform a performance test with for GOOSE messages. These messages are based on the IEC 61850 data set and have the ability to quickly and securely distribute input and output values at the system level, which are transmitted by a...
Development of Structures based on Chitosan-Quince Seed Gum Polyelectrolyte Complex and Mesoporous Silica Nanoparticles for Drug Delivery Application
, Ph.D. Dissertation Sharif University of Technology ; Pircheraghi, Gholamreza (Supervisor) ; Bagheri, Reza (Supervisor)
Abstract
Polyelectrolyte complexes based on polysaccharides have attracted the attention of researchers due to their potential for use in advanced industries. One of the most widely used cationic polysaccharides is chitosan. However, chitosan alone limits applications for smart and sustainable drug delivery due to uncontrolled degradation. For this reason, combining chitosan with another polyelectrolyte and forming a polyelectrolyte complex due to electrostatic interaction has been proposed as a solution. In the first phase of this dissertation, the effects of mixing ratio and concentration of Chitosan and Quince seed gum (QSG) on the physical and rheological properties of chitosan-QSG...
Boundary control of anti-symmetric vibration of satellite with flexible appendages in planar motion with exponential stability
, Article Acta Astronautica ; Volume 147 , 2018 , Pages 219-230 ; 00945765 (ISSN) ; Salarieh, H ; Alasty, A ; Vatankhah, R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
In this research, we have investigated the planar maneuver of a flexible satellite with appendages anti-symmetric vibration. The hybrid governing equations are comprised of coupled partial and ordinary differential equations which are derived by employing Hamilton's principle. In this paper, control goals are the tracking desired pitch angle along with the flexible appendages vibration suppression simultaneously by using only one control torque which is applied to the central hub. The boundary control is proposed to fulfill these control aims; furthermore, this boundary control ensures that spillover instability phenomenon is eliminated, and in-domain sensors and actuators implement are...
Boundary control of flexible satellite vibration in planar motion
, Article Journal of Sound and Vibration ; Volume 432 , 2018 , Pages 549-568 ; 0022460X (ISSN) ; Salarieh, H ; Alasty, A ; Vatankhah, R ; Sharif University of Technology
Academic Press
2018
Abstract
In this paper, the planar maneuver of a flexible satellite with regard to its flexible appendages vibration has been studied. The flexible satellite translates and rotates in a plane; in addition, the flexible appendages can also vibrate in that plane. The system governing equations, which are coupled partial and ordinary differential equations, are obtained based on Hamilton's principle. Then the original system converts to three equivalent subsystems, two of which contains one partial differential equation and one ordinary differential equation along with four boundary conditions, by using change of variables. Employing control forces and one control torque which are applied to the central...
Two statistical methods for resolving healthy individuals and those with congestive heart failure based on extended self-similarity and a recursive method
, Article Journal of Biological Physics ; Volume 32, Issue 6 , 2006 , Pages 489-495 ; 00920606 (ISSN) ; Livari, M. A ; Kaviani, K ; Rahimi Tabar , M. R ; Sharif University of Technology
2006
Abstract
In this paper we introduce two methods for measuring irregularities in human heartbeat time series (HHTS). First we consider the multi-fractal structure of HHTS to distinguish healthy individuals and from those with congestive heart failure. In this way we modify the Extended Self-Similarity (ESS) method and apply it to HHTS. Our second approach is based on the recursive method, which we use to predict the duration of the next heartbeat by considering a few previous ones. We use standard physiological data and show that these approaches lead to very satisfactory methods to resolve the healthy and CHF individuals. These methods can be used potentially in portable electronic heart alarm...
A multi-objective decision-making process of supplier selection and order allocation for multi-period scheduling in an electronic market
, Article International Journal of Advanced Manufacturing Technology ; Volume 52, Issue 9-12 , February , 2011 , Pages 1039-1052 ; 02683768 (ISSN) ; Mahdavi, I ; Ashoori, M. T ; Kaviani, S ; Mahdavi Amiri, N ; Sharif University of Technology
2011
Abstract
Supplier selection is a multi-criteria problem which includes both tangible and intangible factors. In these problems when suppliers have capacity or other different constraints, two questions persist: which suppliers are the best and how much should be purchased from a selected supplier? Here, we propose an integrated approach of analytic hierarchy process (AHP), Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS), and multi-objective nonlinear programming to consider both tangible and intangible factors in choosing the best suppliers and define the optimum quantities among selected suppliers to maximize the total value of purchasing and minimize the budget, total...
Rcci Curvature for Metric-Measure Space via Optimal Transport
, M.Sc. Thesis Sharif University of Technology ; Bahraini, Alireza (Supervisor) ; Ranjbar Motlagh, Alireza (Co-Advisor)
Abstract
One of the important questions in mathematics is generalized. In case of metric spaces, one of the questions is: Can we extend notions of Riemannian geometry to arbitrary metric spaces smoothly? Ricci curvature is one of the most important concepts in differential geometry. Ricci curvature is defined for the Riemannian manifold and has many applications in mathematics and physics like Einstein’s equation in relativity theory. There is a good notion for a metric space having “sectional curvature bounded below by K” or “sectional curvature bounded above by K”, due to Alexandrov. Can we define the concept of Ricci curvature in metric space? A motivation for this question comes from Gromov’s...
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
Seismic design codes reduce loads by using response modification factor. Because of the reserved strength in structural elements and capacity of structure to dissipate energy, structures can be designed for lower seismic loads. This factor has modified over time. In this thesis, the effect of the reduction in behavior factor on the response of two kinds of reinforced concrete systems were evaluated. Moment resisting frames and dual systems with different heights and regularity in plan, heve been design according to the behavior factor which is recommended in the 3rd edition of the Iranian codes of practice for seismic resistance design of buildings (Standard No. 2800). Drift and...
Prediction of Financial Markets Using Combination of Artificial Intelligence and Technical Analysis
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
Generally, nowadays, machine learning methods are used in many different areas for their superiority over other methods of prediction. Although being a tough task, stock market prediction with machine learning approaches is being spread due to satisfying results published ever yday. Machine learning methods usually use varied kinds of data ,including structured data such as market data, technical indicators and some fundamental data as well as unstructured one entailing text and graph data in order to enhance their predictability capacity. In this thesis we aimed to find out more about the importance and the contribution of structured data in prediction and we tried to attain a framework...
Boundary Control of Vibration in Satellite Flexible Solar Panels
, M.Sc. Thesis Sharif University of Technology ; Alasty, Aria (Supervisor) ; Salarieh, Hassan (Supervisor) ; Vatankhah, Ramin (Co-Advisor)
Abstract
Many spacecrafts and satellites have long flexible components, the most common ones are the satellites with flexible solar panels, which are used to provide the satellite energy. The governing equations of the satellite rigid motion along with the solar panels vibrations are the combination of the coupled partial and ordinary differential equations. Various reasons, such as the satellite maneuvers and the external disturbances, cause the vibration of panels. Due to the dependence between the governing equations of the satellite rigid motion and the flexible components vibrations, these vibrations affect the satellite rigid dynamics and the control aims; therefore, in addition to the...
, M.Sc. Thesis Sharif University of Technology ; Hajji, Alireza (Supervisor)
Abstract
This thesis presents an inventory control system which is based on Meta-heuristic Algorithms.In this thesis we will optimize the input values of our tree-echelon inventory model (keeping costs,stock worth,reorder costs,...) with these Algorithms. The presented method is able to determine the optimal stock level, costs of system and number of shipments in the system. The method is basically a decision support system (DES) and it is able to provide the order scheduling parameters of goods at operational level. The aim of the current research is to demonstrate that a Meta-heuristic algorithmis capable of solving complex inventory problems and with future improvements it is able to achieve...
Reduction of Residual Displacement of Concrete Structures by use of High Strength Rebars
, M.Sc. Thesis Sharif University of Technology ; Khalu, Alireza (Supervisor)
Abstract
Reinforced concrete bridge columns located in regions of high seismicity are designed with large ductility capacity for adequate protection against collapse. This type of design tends to result in large permanent displacements. To maximize post-event operability and to minimize repair costs, new design strategies to reduce these residual displacements are necessary. Even though seismic codes ensure life safety for bridges, large residual displacement after severe earthquake may make the bridge useless. For example, after 1995 Hyogo-ken Nanbu earthquake (Japan), more than 100 reinforced concrete bridge columns experienced a tilt angle of more than 1 degree (1.75% drift). These columns had to...