Sharif Digital Repository

In recent years with the increase of cellular phone subscribers, demand for high capacity networks is inevitable. For this reason, different methods have been proposed to increase the channel capacity. One method which has become popular in recent years is utilizing of Smart Antenna Systems. Smart antennas basically attempt to enhance the desired signal power and suppress the interferers by beamforming toward the DOA (direction-of-arrival) of the desired signal and nullsteering in the interferences’ DOAs. Smart Antennas first find the direction of signal sources, and then put the main gain toward the desired signal and put the nulls toward unwanted signals. As a result, we can obtain the... 

Nowadays, competition in supplying the requirement of the customer having become so important and curtail between the companies, so marketing plays an important role in the progress of the firms. Therefore, business and marketing concept is one the important tools to achieve their potential goals in the target markets. For Esfahan Steel Company because of their product’s quality, marketing is so significant. With respect to put the third forge will be put into operation perfectly in this company, the production will be increased and reach to 3.7 million tones per year. In this research, we develop a Marketing Plan for the products of this company in the international target market  

Behavioral investigation and control of multi-agent systems was one of the most attractive problems in robotics which has been studied since the middle of 20th century. Tracking a target is shown by many organic mechanisms during hunting and etc. and is one of the important topics of researches. In this thesis tracking a target by a multi-agent system has been considered which the agents are wheeled mobile robots and have non-holonomic motion constraints. A sample dimensionless and continuous time synchronous dynamic is proposed for the motion of these agents and the goal is to track a moving target while the agents create and keep a desired formation during their tracking process.... 

A group of vehicles are contributed to follow static or dynamic targets in a cooperative target tracking problem. The vehicles estimate the future location of dynamic targets based on the information they receive from other vehicles and targets. Noting to these estimations, the vehicles are able to decide the best movement toward the targets. Various control methods have been presented to solve different problems of target tracking which the majority of them proposed optimal control solutions. A new approach to the problem of tracking dynamic targets via cooperative multi-vehicle systems under the receding horizon control of the vehicles is proposed in this dissertation. A receding horizon... 

Complex networks have recently become a very noticeable subject because of their remarkable theory on real networks such as rumor spreading. This thesis contributes to a prevention strategy which uses a maximal clique algorithm to find overlapping communities and also uses inverse targeting immunization strategy to immune these communities. By the using maximal clique algorithm combined with inverse targeting strategy we have achieved that the TIK method (targeted immunization using k-clique percolation) obtains 10% of better immunization than HD (highest degree) method which is one of the best methods in targeted immunization strategies. The TIK also demonstrates that rumor spreading is... 

Today, advances in technology caused the emergence of a need for intelligent systems which can operate without human supervision, and have variety of applications in security, industry, transportation and sport events. Most of these systems require faster and more accurate object tracking. Lots of surveillance and computer vision applications need a process to detect and track objects. For example, the exact location of objects or people is part of the input for applications like movement analysis, counting the number of items, and recognition of people’s behavior. Occlusion is one of the major obstacles in performance of auto-tracking systems. There are several methods to address this... 

The existing learning methods usually assume that training and test data follow the same distribution, while this is not always true. Thus, in many cases the performance of these learning methods on the test data will be severely degraded. We often have sufficient labeled training data from a source domain but wish to learn a classifier which performs well on a target domain with a different distribution and no labeled training data. In this thesis, we study the problem of unsupervised domain adaptation, where no labeled data in the target domain is available. We propose a framework which finds a new representation for both the source and the target domain in which the distance between these... 

Topic that is investigated in this article include identify and localization a number of aerial target penetrating into a protected by area by a swarm of UAVs is fixed wing. UAVs do not have any prior notice of positioning targets. In addition, it is assumed that lacks any radiation exploitable targets and thus use UAVs for Targets Detection from an active radar system. Obviously this article focus on developing a guidance algorithm UAVs to this particular issue and also as the targets participatory is localization algorithm. In addition, extraction type and performance characteristics radar system required and also performance characteristics of the class of UAVs, which is suitable to... 

The synthetic aperture radar (SAR) is a microwave imaging radar that achieves high resolution while taking advantage of pulse compression technology and the Doppler effect. In typical radar systems, in order to obtain a good azimuth resolution, one should use an antenna with big aperture. However this is not possible in many cases. SAR has overcome this problem by moving the antenna and so making a synthetic aperture. In inverse SAR (ISAR) the radar antenna is static and synthetic aperture is created by the movement of target. Typical SAR imaging aims at the static targets and when the target is moving, it does not operate well. When detecting moving targets by SAR, both radar and target are... 

The traditional machine learning methods assume that the training data and the test data are drawn from the same distribution (or drawn from the same domain). In practice, in many computer vision applications, this assumption may not hold. Unfortunately, the performance of these methods degrades on dataset drawn from a different domain. Domain adaptation attempts to minimize this degradation caused by distribution mismatch between the training and test data. Domain adaptation tries to adapt a model trainded from one domain to another domain. We focus on supervised domain adaptation method in which limited labeled data is available from the target domain. We propose a new domain adaptation... 

Ever growing users’ demand for higher mobile data traffic and a rise in the number of communicating devices in the network oblige operators to design novel schemes in order to respond to users’ requirements. The limited available frequency spectrum cannot handle this increased data traffic demand in cellular networks. It is estimated that by 2020 the amount of traffic in mobile networks, grows ten times more than mobile traffic in 2014. Data offloading is an existing approach that enables operators to support users’ demands. In this approach, in addition to utilizing Wi-Fi technology as a means to transfer data as well as conventional cellular communications, opportunistic communications... 

In this thesis, coupled trajectory and attitude control of an exoatmospheric interceptor is investigated. The interceptor is considered to track and intercept orbital targets in its terminal phase using an infrared strapdown seeker. Attitude control system uses its thrusters in order to keep permanently the detector toward the target in both elevation and azimuth directions. Detector is attached to the body. Divert thrusters generate acceleration perpendicular to the longitudinal axis of the interceptor to correct the trajectory. It is assumed that the interceptor has mass asymmetries. Transltional and rotational dynamics are coupled. Therefore, in order to improve the performance of... 

Target recognition techniques based on micro Doppler phenomenon are popular because they are applicable even on low resolution radars, in contrast to other techniques such as High Resolution Range Profile (HRRP) which need high resolution in range or angle. Usually, main purpose of such techniques is generating robust features against target initial state, velocity, aspect angle, etc. rather than features which exactly identify a target. Main approaches in the literature are based on time-frequency transforms (TFT) such as spectrogram in order to generate features to classify targets, but in this thesis, we propose a totally different method using Recurrence Plot for generating features... 

One of the most useful method in medical imaging is Magnetic Resonance Imaging. Gadolinium base contrast agents used to improve images contrast made by MRI. There are some problems with using these drugs, such as toxicity and lack of targeting. In this research, Silicon nanoparticles were produced by a new fashion of removing template method. Particle size was scanned by Dynamic light scattering (DLS), mesoporous structure was investigated by Brunauer-Emmett-Teller (BET), and amine functionalization was recognized by Fourier transform infrared (FTIR). Functionality was determined by evaluation of signal and relaxation of nanoparticles.T1 was defined by a 1.5 tesla power MRI device. The... 

Several studies based on anti- cancer, anti- metastatic and anti- tumor effects of curcumin have been reported . Besides these benefits, the therapeutic efficacy of curcumin is limited due to its poor aqueous solubility, extensive first-pass metabolism, inadequate tissue absorption and degradation at alkaline pH, which severely diminishes its bioavailability. In this project we seek to solve some of the problems with nanoscience to work more effectively. In the past decade, mesoporous silica nanoparticles (MSNs) have found widespread application as controlled drug delivery systems. Recent reports on the design of capped and gated MSN-based systems have shown promise in preventing premature... 

In this work, we investigate how the so called “Game Theory” could be applied to study the effectiveness of the defensive layers of a high-value target. A High-value target is usually protected by different defensive layers; the characteristics of which very well depends on the attacker capabilities. Here, we show “Game Theory” can effectively provide new alternatives to increase the chance of survival for the “High Value” target by increasing the risks for the attacker. In this work, we assume any attack is not executed in one stage and defensive layers could be designed to increase the duration of the game. We also assume the game ends as soon as there are no more weapons d to protect the... 

There are many methods for direction finding (DF) of radar targets, while the complexity and time elapsed calculation are their main drawbacks, thus the real time implementation of this methods are difficult. Artificial neural network (ANN) for DF is one of the optimum and good ways to implementation that have better result versus other techniques. In this thesis, direction finding problem for radar targets by using artificial neural networks have been studied. A new method is presented to detect the multiple targets simultaneously, that it can be implemented in digital form easily. Here one-dimensional DF by using uniform linear array (ULA) discussed and formulated, then the proposed... 

In the banking and macro-financial literature، banks are modeled as financial intermediaries who give loans to the borrowers from their deposits. In these models، deposits are created from the accumulation of real goods. Besides this view، which is used more in the academic environment، others who are most practical، describe banks not intermediaries، but credit creator which do not need deposits to pay loans. In this research، we use credit creation concept in a Neoclassic environment that the central bank’s monetary policy is fractional reserve to answer this question that if banks could create credit for firms based on its future income، while firms have CIA constraints، how do economic... 

One of the subsets of the radar systems is recognition of targets. Radar Target Recognition (RTR) is a process in which a target is distinguished from a set of targets. To recognize radar targets, we need to extract useful information from the returned signal from them. The most important issues in recognizing radar targets are the selection of information that reduces the amount of information needed for the identification process, the ease of extracting information from the moving target, and the ease of decision making to determine the identity of the target. One method is to produce a high resolution range profile, which is the one-dimensional image of the target in the direction of... 

In the beginning of the 90’s a new type of robot was introduced by Fukuda. The brachiation is a type of mobile robot that moves from branch to branch like a long-armed ape. Here, as a new innovation, optimal control is used to obtain the optimal trajectories for two different problems. The first problem is “Brachiation between fixed branches with different distance and height” and the second is “Brachiating and catching the moving target branch”. Theoretical results show that the control effort in the proposed method is reduced by 25% in comparison with the “Target Dynamics” method which was proposed in prior articles for this robot. The obtained optimal trajectory also minimizes the...