Sharif Digital Repository

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 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... 

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... 

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... 

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... 

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... 

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... 

Ultrafast signal processing in time-domain with high resolution and reconfigura-bility is a challenging task. This paper, for the first time, introduces a time-varying metasurface consisting of graphene microribbon array for implementing time-lens in the terahertz domain. Given that the surface conductivity of graphene is proportional to the Fermi energy level in the THz regime, it is possible to change the phase property of the incident electromagnetic pulse by changing the Fermi level while the Fermi level itself is a function of voltage. Upon this fact, a quadratic temporal phase modulator, namely time-lens has been realized. This phase modulation is applied to the impinging signal in the... 

In today's era, metal nanoparticles play an important role in technologies emerging from different sciences, such as chemistry, physics, optics, material science, due to their unique characteristics. In the development of nanooptics science, it can be said that metal nanoparticles play an important role. The ability of conductive electrons collective oscillation causes surface charge density fluctuations in nanoparticles, this phenomenon is known as surface plasmons. Surface plasmons are surprisingly coupled with light and cause the significant increase in the intensity of optical fields induced in nanoparticles. Therefore, with the presence of localized surface plasmons or plasmon... 

Understanding of the Molecules is the main purpose of the chemistry. Ab-initio molecular dynamics (AIMD) as a branch of the computational chemistry, tries to give us a deep comprehension of the molecule, and its chemical, physical and optical activities. This comprehension, relies on the accuracy of quantum mechanics, in addition to the speed of the classical mechanics. The mixing of the quantum mechanics and the classical mechanics could simulate activities of the atoms in the time-domain, provided the mixing is done with precaution. This, in turn, helps us to forecast the response of a molecule in different situations, and also translating the macroscopic phenomena in a nanoscopic... 

To date, the plasmonic properties of many metallic and semi-conducting materials have been investigated and used in various industries. One of the plasmonic material categories that have always been considered is polycyclic aromatic hydrocarbon or PAH, whose plasmonic resonance energy depends on the charge state of the molecule. In this regard, it is easy to change the plasmonic resonance energy via changing the induced charge, which is a unique feature of the mentioned materials. In addition, plasmonic structures with excitations in the infrared region are able to enhance the vibration intensity of absorbed molecules by increasing the electric field around themselves. Therefore, they have...