Sharif Digital Repository

A brief overview of the proposed research, its aims, engineering relevance and applications; as well as expected achievements compared to the present state of the art:The plastic hinge length and ultimate drift calculations of frames are required in the performance based design of reinforce concrete structure. FRP-confinement increases the column’s shear resistance and ductility. FRP-confinement prevents concrete cover from spalling and increases the inelastic deformability of concrete in the potential plastic hinge region. GU et al. 2012 [24] studied the existing experimental results of confinement effects on the plastic hinge length. Mortezaei and Ronagh, 2012 [25], studied the plastic... 

A drug can be defined as a substance made to prevent disease, cure a specific symptom, relieve pain, and reduce anomalies in the body. The process of drug designing is so laborious, complex, costly, and time-consuming that chance of failure during the lab experiment stages is high. These challenges have persuaded researchers to find new usage for existing drugs, referred to as drug repurposing, with the main advantage of reducing cost, risk, and time. To this aim, computational methods have been applied to discover hidden pharmaceutical capabilities of drugs in terms of predicting whether a particular drug can interact with a particular protein.Graph Neural Networks (GNNs) have recently... 

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... 

This thesis is about multidisciplinary design optimization of MRI ¬controlled robots with a nonlinear model approach in the cardiovascular system and simulates its behavior to reach cancer cells. Such robots, designed to perform medical procedures with minimal side effects to the patient, include a set of ferromagnetic nanoparticles attached to the polymer and disposable drugs such as cancer drugs.The disciplines considered in this issue include structure, hydrodynamics, propulsion, controllability, and trajectory. The proposed model in this study, in addition to the main forces acting on the robot such as magnetic force, hydrodynamics, and apparent weight, also examines other forces due to... 

One of the most important issues among defense is the increasing of the defense power using present facilities. Therefore, optimal setting and arrangement of equipment by considering different air-to-earth attack of enemy without knowing of properties and capabilities of available systems may not be possible. So, using defense equipment considering properties of them, and paying attention to existence restrictions and effective elements can have an effective role with the design of suitable algorithm.The main purposes of this thesis are: maximization of the efficiency of a defense system against. aerial invader targets, achieving the best arrangement of defense equipment based on suggested... 

In this document, the cooperative estimation of states between two interceptors and one target is expressed in order to evaluate the effect of information sharing in different situations on the estimation performance. Due to the importance of the proper estimation of the target acceleration in advanced navigation rules, the main focus of the document is on a more precise estimation of the absolute states of the target. For this purpose, a filter based on the extended Kalman filter was used as an estimator, and to evaluate the promotion of the estimation performance, the combination of measured data was used in two different ways. Matlab Simulink is the simulation software used. The dynamics... 

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... 

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... 

In this thesis, the effect of elastodynamic behaviour of an interceptor on it’s trajectory in space and accuracy in desired positioning and situation is investigated. The governing equations of motion are derived and linearized by using the basic equations of motion in the body frame axes and the mode summation method for elastic deformations. In order to control the interceptor, the closed-loop control on the yaw and pitch angles, is considered. The governing equations of motion are solved to determine the time response to investigate the structural effects on the stability, position and situation of interceptor. Finally, the effect of elasticity and vibrations on the interceptor’s... 

In this project, a method for cooperative search and localization of RF ground moving targets by a group of UAVs is developed. It should be noted that UAVs are just equipped with GPS and directional sensors. Since there is fuel constraint for UAVs, they take fuel from a tanker whenever they require. Moreover, searching method enables the UAVs to see different parts of the desired area with almost uniform distribution. In addition, the proposed approach enables the UAVs to perform a local search with the aim of finding the targets having lost their signal during localization mode. Finally, based upon a fueling decision function the UAVs take turn, approach to the fuel tanker, and start... 

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... 

In this thesis a hybrid guidance law has been designed for a ground-based system to intercept an exoatmospheric target. In this regard a three stage interceptor with a kinetic kill vehicle has been proposed, the design parameters of which are determined according to a conceptual design procedure. The guidance law consists three phases namely boost, midcourse and terminal phases. In boost phase, a ballistic guidance law steers the first and the second stages of the interceptor ahead of the predeicted intercept point. In the midcourse phase, the third stage of the interceptor corrects the engagement plane while it also provides the head on interception condition for the kinetic kill vehicle.... 

In much of the financial economics literature, banks are modeled as financial intermediaries that transfer household deposits to loan applicants. In these models, deposits are obtained from the accumulation of real amounts (household savings). In addition to this, another approach describes banks not as intermediaries of loanable funds, but as money-creators who do not need to accumulate deposit resources to lend. In this study, by modeling the money-creation behavior of the banking network, we try to answer the question that if the bank can create credit and purchasing power for the firm based on its future income, how will the general variables of the economy, including consumption and... 

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... 

Drug-target binding affinity prediction is one of the most important and vital part of drug discovery. The computational methods to predict binfing affinity is a standing challenge in drug discovery. State-of-the-art models are usually based on supervised machine learning with known label information. It is expensive and time-consuming to collect labeled data. This thesis proposes a semi-supervised model based on convolutional GAN (Generative adversarial networks). The model consists of two Gans and Two CNN blocks for feature extraction and fully connected layers for prediction. Gan can learn protein and drug features from unlabeled data. We evaluate the performance of our method using four... 

Multiple object tracking refers to the detection and following of target object classes in video sequences. In this task, all objects belonging to the target classes in the video are detected simultaneously in each frame, and a unique ID is assigned to each of them throughout the video. In recent years, the use of graph neural networks for solving this problem has received significant attention because these models are suitable tools for discovering and improving the relationships between objects in the scene, which can greatly assist in better object pairing. However, there are various challenges to using graph neural networks, the most important of which is the limitation of input graph... 

Branch Target Buffer is a widely used component in modern processors. While there are different designs for BTB, they generally have a set-associative structure keeping branches and their target to help the frontend fetch the instructions on the correct path. To achieve high performance, it’s essential to obtain a high hit rate out of the BTB. Prior works has shown that BTB suffers from frequent misses that require large sizes or sophisticated BTB prefilling mechanisms to overcome the problem. However, the first solution imposes a significant storage overhead, and the latter results in limited benefits. Prior works have shown that branches exhibit different behaviors from being strongly... 

Recently, advances in the fabrication and integration of sensing, communication technologies and economical deployment of large scale sensor networks which are capable of large scale target tracking, become possible.therfore, the wireless sensor networks are a fast growing and marvelous research area that has attracted considerable research attention in the recent past. The creation of large-scale sensor networks interconnencting several hundered to a few thousand sensor nodes opens-up several wide range of application and technical challenges. Sensor nodes have been deployed to play significant roles in battlefield, disaster-prone area, traffic control, habitat monitoring and intruder... 

The frontend stalls caused by instruction cache and branch target buffer (BTB) misses are a well-known source of performance degradation in server processors.To address this limitation, a myriad of hardware prefetchers are proposed. While they can effectively eliminate lots of misses and increase performance, they are impractical solutions due to some shortcomings. In this study, we are looking for effective and practical solutions to address these limitations.Since the considerable fraction of instruction cache misses is sequential misses,sequential prefetchers like next-line prefetcher are simple and effective solutions to remove sequential misses that are used in modern server processors.... 

Characterizing cellular states in response to various disease conditions is an important issue which is addressed by different methods such as Large-scale gene expression profiling. One of the most important challenges in front of bioinformaticians is the loss of data because expression profiling is still very expensive. It is understood that profiling a group of selected genes could be enough for understanding all of the gene expression profile.In this research, we propose a fast method for estimation of the missing values inlow-rank matrices. We consider the highly correlated expression profiles as a low-rank matrix. Then, we used this new method in a proposed algorithm which will select...