Sharif Digital Repository

Due to the ever-growing applications of video signals in day-to-day life and the large amount of information they contain, the compressing and processing of these signals is vital. In this thesis, a deep neural network called MC-ResNet is proposed which provides an approximation of non-reference frames based on reference ones. Next, three scenarios for compressed video sensing are presented. In all three scenarios, the reference frames are sampled and transmitted independently and reconstructed in the receiver by BCS-SPL method. In the first scenario, the difference between the non-reference frame and the approximation obtained from the MC-ResNet network is sampled and transmitted. In the... 

The ever-increasing demand for wireless communication has raised the need for better utilization of bandwidth and energy. Intelligent Reflecting Surface (IRS) is an emerging technology that has been proposed for the sixth generation of wireless communication. In this thesis, we study the essential role these surfaces can play in improving the physical layer security.First, we consider a relatively realistic scenario for the location of the eavesdroppers. In this scenario, we will assume that the transmitters, users, and eavesdroppers all use a single antenna configuration, and the eavesdroppers are placed randomly across the studied region. Two notable parameters in physical layer security,... 

According to the goals of new generation of wireless communication networks, which include increasing data transfer speed, reducing latency, optimizing power consumption, and increasing the quality of communication, the use of intelligent surfaces to change and control the wireless transmission environment to achieve the goals of new wireless networks has emerged as an effective solution. Finding the location of a user connected to a wireless network for issues like navigation or traffic control has also long been under consideration, and a variety of business systems have been introduced for positioning. Given that the accuracy and speed of finding the user's position is one of the... 

Molecular communication (MC) is a new paradigm, in which the molecules or ions are used as information carriers. MC has been proposed as a promising approach for abnormality detection and localization in a variety of micro-scale and macro-scale applications in biotechnology, medicine, and industry; such as air pollutant monitoring, agriculture, abnormality detection in pipelines, and drug delivery. The goal in some of these works is to detect the tumors, viruses, and infectious micro-organisms in the body or leakage and pressure drop in pipelines. If these abnormalities are detected, the next step would be localizing them to finding a solution or treatment, e.g., drug delivery, or targeted... 

In this paper, controlling the cutting force of an end-milling process using a supervisory fuzzy controller has been investigated. The proposed control consists of an ordinary fuzzy controller and a fuzzy supervisor. In a machining process, there are several parameters which do not contribute to the force control system directly. Therefore an ordinary fuzzy force controller is suitable when these parameter have only small amount of variations. Since in practice this assumption is not valid, then a supervisory fuzzy controller has been added to the system. The designed fuzzy supervisor, inspects the dynamic behavior of the cutting force, estimates a pre-defined ‘sensitivity’ parameter and... 

According to the statistical studies, knee pain is the most common and costliest disorder after low back pain. One of its types is the patello-femoral disorder and instability. Patellar instability can be affected by different factors, such as: low depth of the trochlear groove, low height of the lateral femoral condyle, high length of the patellar tendon, abnormal lateral rotation of the tibia, unusual tibial attachment of the patellar tendon, small patellar size, general loosening of ligaments, etc. So, the mechanical properties of knee joint including patello-femoral joint, surrounding soft tissues, and incoming forces must be examined carefully, in order to find out suitable and... 

In the resent years, social robots has been emerged to improve the interactions between humans and robots. These intractions are intended more in human environment. So the reasonable performance of such robots is achieved if robots’ motion; become similar to humans. Hence, despite the complexities of manufacturing and controlling the bipedal and humanoid robots, the researches on this class of robots are still in continuing more and more. In 2013, the humanoid robot, R-50, made by Robokind Company, was purchased by the Mechanical Engineering Department of Sharif University of Technology. This robot was named Mina and to be used in the researches on the treatment of autism patients. Although... 

Nowadays, with the advent of Autonomous Vehicles(AV), Researchers in different areas focused more on this type of vehicle. Research shows that autonomous vehicles are faster and more precise than Human-driven vehicles(HDV). So if all the users in a road use autonomous Vehicles, the road’s capacity increases; this Thesis develops a mathematical approach for designing AV exclusive lanes for a time horizon in which there are two types of AVs and HDVs on the road. Considering each type of vehicle’s relative performance for an OD pair in the given year, the demand for that OD pair for the next year calculates with a diffusion model. Designing AV exclusive lanes problem is formulated in a bi-level... 

In this thesis, interference management techniques, including frequency, power, and space resource managements in two tier femtocell networks are investigated with the aim of increasing the throughput and decreasing the outage probability for both femto and macro users. Previous studies indicate that Fractional Frequency Reuse (FFR) is an effective interference management scheme for OFDMA based two tier femtocell networks. In this thesis, based on FFR scheme, in the first part, a comprehensive method to model the cross tier interference in both uplink and downlink, and for closed access as well as open access femtocells is introduced and by using this model, a static frequency and power... 

Relay-assisted communication is one of the promising techniques that have been proposed for wireless networks. The main idea of a relay network is to improve data transmission efficiency by using intermediate relay nodes which support data transmission from a source to a destination. From another perspective, energy consumption has recently become an important consideration for design of wireless communication networks. The shrinking size and increasing density of next-generation wireless devices imply reduced battery capacities, indicating that designing energy efficient networks is of paramount importance. In this regard, recent emphasis on green communications has generated great...