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    Analysing of 3D beamforming in MIMO radars

    , Article Proceedings of the 2012 World Congress on Information and Communication Technologies, WICT 2012 ; 2012 , Pages 745-749 ; 9781467348041 (ISBN) Roshanzamir, A ; Bastani, M. H ; Roshanzamir, M ; Machine Intelligence Research Labs (MIR Labs) ; Sharif University of Technology
    2012
    Abstract
    A multiple input multiple output (MIMO) radar system is an emerging research field which has attracted many studies in recent years. This type of radar, unlike conventional phased array radar, can transmit different probing signals via its antennas, that may be correlated or uncorrelated with each other. This waveform diversity offered by MIMO radar systems enable superior capabilities compared to conventional phased array radar. Many papers have introduced different ways for beamforming of MIMO radar. In this paper it is desirable to analysis some methods for beamforming of MIMO radars with planar arrays constellation and examine their 3D result beam-pattern of such constellations for... 

    Advantages of MIMO waveform in sidelobe blanker system

    , Article International Conference on Electronic Devices, Systems, and Applications ; 2012 , Pages 244-247 ; 21592047 (ISSN) ; 9781467321631 (ISBN) Roshanzamir, A ; Bastani, M. H ; Sharif University of Technology
    2012
    Abstract
    A multiple-input multiple-output (MIMO) radar system., unlike a standard phased array radar., can choose freely the probing signals transmitted via its antennas to maximize the power around the locations of the targets of interest., or more generally to approximate a given transmit beam-pattern., or to minimize the cross-correlation of the signals reflected back to the radar by the targets of interest. In this paper it will be shown that how these more degrees of freedom to choose freely between probing signals in a MIMO radar can help to have an omnidirectional beam-pattern for a side-lobe blanker system., and it will be shown that with utilizing MIMO radars for a side-lobe blanker system.,... 

    MIMO radar with phase-coded waveforms

    , Article Proceedings of IEEE East-West Design and Test Symposium, EWDTS 2013, Rostov-on-Don ; Septembe , 2013 , Page(s): 1 - 4 ; 9781479920969 (ISBN) Roshanzamir, A ; Bastani, M. H ; Sharif University of Technology
    2013
    Abstract
    A multiple input multiple output (MIMO) radar system, unlike a conventional phased array radar, can choose freely the signals which transmitted via its antennas to maximize the power around the locations of the specific targets, or more generally to approximate a given transmit beampattern, and also to minimize the cross-correlation of the signals reflected back to the radar by the targets of interest. In this paper we use of phase-coded signals and show how the above desirable features of MIMO radars with some operational consideration can help us to have a desire beampattern. We suppose that for a collection of phase-coded signals, the elements of transmitted signals cross-correlation... 

    Analysing of binary PAM systems in digital communication

    , Article International Conference on Communication Technology Proceedings, ICCT ; 2012 , Pages 1240-1246 ; 9781467321013 (ISBN) Roshanzamir, A ; Bastani, M. H ; Sharif University of Technology
    2012
    Abstract
    In this era of digital communication systems, different factors are included in efficiency of a transceiver system. Binary PAM systems are one of these transceiver systems. Many aspects of such a system has been considered yet but this field needs more research on because this is the base of any communication system. In this paper, effects of transmitter and receiver filters, noise, duty-cycle and time mismatch between transmitter and receiver in a binary baseband PAM transceiver system is analyzed. Simulation is performed to analyze the above effects on a typical communication system with 10 bits of transmit. MATLAB software is being employed for simulations  

    Multipath effect on false peaks in covariance based MIMO radar beampattern design

    , Article Proceedings International Radar Symposium, Dresden ; Volume 2 , June , 2013 , Pages 970-975 ; 21555753 (ISSN) ; 9783954042234 (ISBN) Roshanzamir, A ; Bastani, M. H ; Sharif University of Technology
    2013
    Abstract
    In a Multiple Input Multiple Output (MIMO) radar unlike conventional phased array radar, we can choose freely between the probing signals transmitted via its antennas to maximize the transmitted power around specific target locations or to approximate a desire beam-pattern in different manners that many papers have taken into consideration so far. In an operational radar or communication environment, one of the usual phenomenon that happens is multipath. In this paper we'd like to take this effect into consideration and show that how this effect can influence our beam-pattern in a covariance based MIMO radar beam-forming. We will show that multipath can change beam-pattern peak direction,... 

    Hybrid orthogonal-phased array MIMO RADAR

    , Article IET Conference Publications ; Volume 2013, Issue 617 CP , 2013 ; 9781849196031 (ISBN) Roshanzamir, A. S ; Bastani, M. H ; Sharif University of Technology
    2013
    Abstract
    Multiple Input Multiple Output (MIMO) radar is a multiple aperture technology characterized by the ability to transmit diverse signals at each aperture. This is in contrast to traditional phased array radar whereby a single signals is transmitted with a phase shift applied at each element to enable steering of the transmit beampattern. The hybrid MIMO phased array radar (HMPAR) concept is an outgrowth of the monostatic MIMO construct, in which all sensors have the same view of the far field target which is known as colocated antenna. In the HMPAR, the full transmit array is partitioned into sub-arrays which can be electronically steered in different directions and driven by separate transmit... 

    Phased array radar beamforming method based on MIMO radar covariance

    , Article IET Conference Publications ; Volume 2013, Issue 617 CP , 2013 ; 9781849196031 (ISBN) Roshanzamir, A. S ; Bastani, M. H ; Sharif University of Technology
    2013
    Abstract
    A multiple input multiple output (MIMO) radar is an emerging field which has attracted many researchers recently. In this type of radar, unlike an standard phased array radar, one can choose transmitted probing signals freely to maximize the power around the locations of the targets of interest, or more generally to approximate a given transmit beam-pattern, or to minimize the cross-correlation of the signals reflected back to the radar by the targets of interest. These signals can be correlated to each other or noncorrelated. Many papers have investigated beampattern design and waveforming in MIMO radars. One of the most famous approaches for beampattern design is named covariance based... 

    Transformer-based deep neural network language models for Alzheimer’s disease risk assessment from targeted speech

    , Article BMC Medical Informatics and Decision Making ; Volume 21, Issue 1 , 2021 ; 14726947 (ISSN) Roshanzamir, A ; Aghajan, H ; Soleymani Baghshah, M ; Sharif University of Technology
    BioMed Central Ltd  2021
    Abstract
    Background: We developed transformer-based deep learning models based on natural language processing for early risk assessment of Alzheimer’s disease from the picture description test. Methods: The lack of large datasets poses the most important limitation for using complex models that do not require feature engineering. Transformer-based pre-trained deep language models have recently made a large leap in NLP research and application. These models are pre-trained on available large datasets to understand natural language texts appropriately, and are shown to subsequently perform well on classification tasks with small training sets. The overall classification model is a simple classifier on... 

    Beampattern Design in Non-uniform MIMO Radars

    , M.Sc. Thesis Sharif University of Technology Roshanzamir, Amirsadegh (Author) ; Bastani, Mohammad Hassan (Supervisor)
    Abstract
    Multiple Input Multiple Output (MIMO) radar is an emerging technology which has attracted many researchers recently. The problem of beampattern design of a MIMO radar in uniform arrays and with the covariance based method of point targets has been investigated by many papers so far. In this thesis it is desirable to consider this problem in non-uniform arrays. Many authors have designed the transmitted beampattern by means of designing the cross correlation matrix of transmitted signals elements, but in this paper optimizing the locations of transmitted antennas will be done as well as cross correlation matrix of transmitted signals to achieve a better results  

    Computer aided decision making for heart disease detection using hybrid neural network-Genetic algorithm

    , Article Computer Methods and Programs in Biomedicine ; Volume 141 , 2017 , Pages 19-26 ; 01692607 (ISSN) Arabasadi, Z ; Alizadehsani, R ; Roshanzamir, M ; Moosaei, H ; Yarifard, A. A ; Sharif University of Technology
    Elsevier Ireland Ltd  2017
    Abstract
    Cardiovascular disease is one of the most rampant causes of death around the world and was deemed as a major illness in Middle and Old ages. Coronary artery disease, in particular, is a widespread cardiovascular malady entailing high mortality rates. Angiography is, more often than not, regarded as the best method for the diagnosis of coronary artery disease; on the other hand, it is associated with high costs and major side effects. Much research has, therefore, been conducted using machine learning and data mining so as to seek alternative modalities. Accordingly, we herein propose a highly accurate hybrid method for the diagnosis of coronary artery disease. As a matter of fact, the... 

    An expert system for selecting wart treatment method

    , Article Computers in Biology and Medicine ; Volume 81 , 2017 , Pages 167-175 ; 00104825 (ISSN) Khozeimeh, F ; Alizadehsani, R ; Roshanzamir, M ; Khosravi, A ; Layegh, P ; Nahavandi, S ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    As benign tumors, warts are made through the mediation of Human Papillomavirus (HPV) and may grow on all parts of body, especially hands and feet. There are several treatment methods for this illness. However, none of them can heal all patients. Consequently, physicians are looking for more effective and customized treatments for each patient. They are endeavoring to discover which treatments have better impacts on a particular patient. The aim of this study is to identify the appropriate treatment for two common types of warts (plantar and common) and to predict the responses of two of the best methods (immunotherapy and cryotherapy) to the treatment. As an original work, the study was... 

    Alzheimer’s Disease Diagnosis using Description Test

    , M.Sc. Thesis Sharif University of Technology Roshanzamir, Alireza (Author) ; Soleymani Baghshah, Mahdieh (Supervisor) ; Karbalaei Aghajan, Hamid (Supervisor)
    Abstract
    There are currently about 50 million people with Alzheimer's disease in the world, and this number is about 700 thousand in Iran. The symptoms of the disease include decreased awareness, disinterest in unfamiliar subjects, increased distraction, speech problems, and etc. which gradually leads to an absolute inability to perform daily activities and completely mute. The disease belongs to the category of neurological disorders and is the most common type of dementia for which no treatment has been offered so far. However, if the disease is diagnosed in its early stage, a series of pharmacological and behavioral therapy approaches can be prescribed to reduce the pace or progression of the... 

    Fabrication of Nuclear Fuel Pellet With a Mixture of Micro and Nano UO2 Powders And Investigation of Its Physical and Mechanical Properties

    , M.Sc. Thesis Sharif University of Technology Karami, Mahdiyeh (Author) ; Otukesh, Mohammad (Supervisor) ; Taghizade, Mohammad (Supervisor) ; Roshanzamir, Manouchehr (Co-Advisor)
    Abstract
    Uranium dioxide (UO2) has been widely used as nuclear fuel in water cooled reactors since 1960s. UO¬2 is a refractory oxide with a melting point in excess of 28000C and therefore, requires high sintering temperature around 17000C in a hydrogen atmosphere for several hours. In the conventional method, the sintering is incorporated with indirect heating of green pellets in a refractory-type electrical resistance furnace. This furnace, however, uses a large number of expensive heating elements and refractory materials to achieve and maintain the high temperature for a long time. Moreover, it consumes much electrical energy and time. Since nanocrystalline materials contain a large fraction of... 

    Rcci Curvature for Metric-Measure Space via Optimal Transport

    , M.Sc. Thesis Sharif University of Technology Taheri, Abolfazl (Author) ; 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 (Author) ; 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 (Author) ; 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... 

    , M.Sc. Thesis Sharif University of Technology (Author) ; 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... 

    The Ricci Flow with Applications to the Poincare and Calabi Conjectures

    , M.Sc. Thesis Sharif University of Technology Safdari, Mohammad (Author) ; Bahreini, Alireza (Supervisor)
    Abstract
    Poincare conjecture is one of the rst eorts for classifying 3-manifolds that was stated in the begining of 20th century. Eorts for proving this conjecture continued for about 100 years and nally Perelman has solved it in 2003. He has used Ricci ow which has been invented by Richard Hamilton in the early 80's. In this thesis rst we will introduce Ricci ow and will state the results before Perelman such as short time and long time existence of solution. Then we will mention some applications of Ricci ow and will state an explanation of the proof of uniformization and Calabi conjecture by Ricci ow. After that we start the main part of the thesis. In this part we will montion one of the... 

    Feasibility And Study(CNG Cylinder Production Plant)

    , M.Sc. Thesis Sharif University of Technology Mousavi, Mohammad (Author) ; Haji, Alireza (Supervisor)
    Abstract
    Nowadays best using of fossil fuels sources of the country (and) importance of comparison against lack of capacity in petrol production make determined the programmers and the directors to foresee and design expanded programs of the goals, to use natural gas for car fuels. To reach fulfillment of these programs, the confirmed needs of the natural gas cylinders are improved and make it essential to invest on producing compressive natural gas cylinders. In this way economical and technical change researches has been done in order to construct on department to produce 200,000 compressive natural gas cylinders in a year during two sets.(shifts) According to the results of technical researches... 

    Synthesis, Characterization and Field Emission Study of Molybdenum Oxide (MoOx)Nanostructures

    , M.Sc. Thesis Sharif University of Technology Khademi, Ali (Author) ; Moshfegh, Alireza (Supervisor)
    Abstract
    Different molybdenum oxide nano/micro structure thin films were synthesized by thermal evaporation method under various growth conditions such as deposition time, temperature and evaporation source-substrate distance. Molybdenum oxide nanostructures grown on Si(100) such as nanowalls, nanostars and nanowires were characterized with scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM). Shape and type of nanostructures were determined with SEM, AFM and HRTEM analysis. XPS analysis showed that the synthesized nanostructures contained Mo6+, Mo5+, Mo4+ and...