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Analysis and design of multi-stage wideband LNA using simultaneously noise and impedance matching method
, Article Microelectronics Journal ; Volume 86 , 2019 , Pages 97-104 ; 00262692 (ISSN) ; Medi, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
An analytical approach for design optimization of multi-stage LNAs with common source topology is developed. This paper reviews and analyses simultaneous noise and input impedance matching in three different topologies including common source amplifier with inductive degeneration, resistive feedback and dual feedback in order to achieve maximum available gain and minimum possible noise figure (NF). A study on multi-stage LNAs is performed to calculate optimum input impedance of each stage for minimum overall NF while considering the gain and NF of that stage in addition to the effect of noise of the following stages. MATLAB was used to calculate the starting point of design optimization in a...
Noise Analysis and LNA Design in Microwave Band
, M.Sc. Thesis Sharif University of Technology ; Medi, Ali (Supervisor)
Abstract
In recenet years the use of microwave integrated circuits for military and commercial applications has gained much more attention. The advent of monolithic microwave integrated circuits, which provide the possibility of fabrication of amplifiers in large number, sufficient accuracy an affordable price has accelerated this process. Low noise amplifiers as the first blocks in the receiver modules are such circuits that are highly regarded in this field. This block is a key block in the receiver which its noise figure and gain directly affect the sensitivity and dynamic range of the receiver. As a result, a low noise amplifier with low noise figure, high gain, good return loss, low power...
Supervisory Model-based Predictive Control for Voltage Regulation of a Grid-Connected Wind Farm
, M.Sc. Thesis Sharif University of Technology ; Sadati, Nasser (Supervisor)
Abstract
Concerns about fossil fuels and the consequent effects of burning such fuels on the environment have drawn attention of different countries around the world to the development of renewable energy systems, and it has encouraged researchers to focus on expanding the methods of using different sources of renewable energy. One of the most important renewable energies is wind energy, which is generated by wind turbines. A cluster of wind turbines forms a wind farm. Wind turbines can be equipped with a supervisory control system that sends the data measured by the sensors to the operator. Design of supervisory control algorithm for a wind farm requires a model of the wind farm system. The task of...
Reliability Improvement in Network on Chip against Soft Errors Considering Multiple Bit Upsets
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Ghassem (Supervisor)
Abstract
Network on chips (NoCs) have emerged as a feasible solution to handle growing number of communicating components on a single chip. The scalability of chipsincreases the probability of errors and making the reliability a major issue in scaling chips. Soft errors and crosstalk faults are the most important fault sources which can decrease the reliability of NoCs. The probability of Soft errors has increased by about 6 to 7 times by scaling from 130 to 30 nm technology. Since buffers occupy in about 40% to 90% of the area of switches, the probability of a multiple bit upset in a switch buffers is noticeable. In NoC architecture, a packet is broken down into multiple flow control units called...
Preparation of poly(vinyl chloride) (PVC) ultrafiltration membranes from PVC/additive/solvent and application of UF membranes as substrate for fabrication of reverse osmosis membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 21 , 2018 ; 00218995 (ISSN) ; Asadollahi, M ; Musavi, A ; Bastani, D ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Ultrafiltration (UF) membranes were prepared from poly(vinyl chloride) (PVC) as main polymer, poly(vinyl pyrrolidone) (PVP) as additive, and 1-methyl-2-pyrrolidone (NMP) as solvent using Design Expert software for designing the experiments. The membranes were characterized by SEM, contact angle measurement, and atomic force microscopy. The performance of UF membranes was evaluated by pure water flux (PWF) and blue indigo dye particle rejection. In addition, the molecular weight cutoff of UF membranes was determined by poly(ethylene glycol) (PEG) rejection. The UF membranes were used as substrates for fabrication of polyamide thin film composite (TFC) reverse osmosis (RO) membranes. The...
Non-Destructive estimation of physicochemical properties and detection of ripeness level of apples using machine vision
, Article International Journal of Fruit Science ; Volume 22, Issue 1 , 2022 , Pages 628-645 ; 15538362 (ISSN) ; Nadimi, M ; Abbaspour Gilandeh, Y ; Paliwal, J ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Nondestructive estimation of physicochemical properties, post-harvest physiology, and level of ripeness of fruits is essential to their automated harvesting, sorting, and handling. Recent research efforts have identified machine vision systems as a promising noninvasive nondestructive tool for exploring the relationship between physicochemical and appearance characteristics of fruits at various ripening levels. In this regard, the purpose of the current study is to provide an intelligent algorithm for estimating two physical properties including firmness, and soluble solid content (SSC), three chemical properties viz. starch, acidity, and titratable acidity (TA), as well as detection of the...
Fabrication of Enzyme Biosensor for Heavy Metal Detection
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Sabzi, Reza (Supervisor)
Abstract
In this project identification of heavy metals has been studied by using glucose oxidase enzyme. Measurement of heavy metals such as mercury (II) nitrate, lead (II) nitrate and cadmium nitrate are based on inhibitory of glucose oxidase enzyme. To do this, two modified electrodes has stabilized on a graphite electrode. Nanocomposite of single wall carbon nanotube with Nile Blue is foundation of the first working electrode. Biological component of the electrode is glucose oxidase enzyme that bovine serum albumin and glutaraldehyde are helping enzyme in immobilization and these materials cause enzyme to cross link with the foundation. This biosensor has great stability and suitable linear...
Advances in heuristic signal processing and applications
, Book ; Chatterjee, Amitava ; Nobahari, Hadi ; Siarry, Patrick
Springer
2013
Abstract
There have been significant developments in the design and application of algorithms for both one-dimensional signal processing and multidimensional signal processing, namely image and video processing, with the recent focus changing from a step-by-step procedure of designing the algorithm first and following up with in-depth analysis and performance improvement to instead applying heuristic-based methods to solve signal-processing problems. In this book the contributing authors demonstrate both general-purpose algorithms and those aimed at solving specialized application problems, with a special emphasis on heuristic iterative optimization methods employing modern evolutionary and swarm...
Preparing an Appropriate UF Membrane from PVC to Use it as Substrate in Sea Water Desalination RO Membranes
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daruoosh (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
In this study the main goal is preparing an appropriate UltraFiltration membrane from PolyVinyl Chloride for using as substrate in producing efficient Reverse Osmosis membranes to use in sea water desalination. each membrane should have some specifications to use it as reverse osmosis membrane’s substrate. One of the most important specifications is the appropriate pore sizes. To investigate this subject pure water flux and PolyEthylene glycol rejection of prepared membranes is tested. After investigation of this parameters and proving them, RO membranes are prepared using this membranes.
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
From Harvest to Market: Non-Destructive Bruise Detection in Kiwifruit Using Convolutional Neural Networks and Hyperspectral Imaging
, Article Horticulturae ; Volume 9, Issue 8 , 2023 ; 23117524 (ISSN) ; Pourdarbani, R ; Sabzi, S ; Rohban, M. H ; Arribas, J. I ; Sharif University of Technology
Multidisciplinary Digital Publishing Institute (MDPI)
2023
Abstract
Fruit is often bruised during picking, transportation, and packaging, which is an important post-harvest issue especially when dealing with fresh fruit. This paper is aimed at the early, automatic, and non-destructive ternary (three-class) detection and classification of bruises in kiwifruit based on local spatio-spectral near-infrared (NIR) hyperspectral (HSI) imaging. For this purpose, kiwifruit samples were hand-picked under two ripening stages, either one week (7 days) before optimal ripening (unripe) or at the optimal ripening time instant (ripe). A total of 408 kiwi fruit, i.e., 204 kiwifruits for the ripe stage and 204 kiwifruit for the unripe stage, were harvested. For each stage,...
Effect of CO2-laser irradiation on properties and performance of thin-film composite polyamide reverse osmosis membrane
, Article Korean Journal of Chemical Engineering ; Volume 33, Issue 3 , 2016 , Pages 1028-1036 ; 02561115 (ISSN) ; Mousavi, S. A ; Farhadi, F ; Vatanpour, V ; Sabzi, B ; Chenari, Z ; Sharif University of Technology
Springer New York LLC
2016
Abstract
CO2-laser irradiation was used to modify the surface properties of thin-film composite (TFC) polyamide reverse osmosis (RO) membranes. These membranes were first synthesized via interfacial polymerization of m-phenylenediamine (MPD) monomers and trimesoyl chloride (TMC) over porous polysulfone ultrafiltration support, followed by a CO2-irradiation. AFM, ATR-FTIR, SEM and contact angle measurements were used to characterize the surface properties of these membranes. The ATR-FTIR results indicated that CO2-laser irradiation did not induce any functional groups on the membrane surface. However, it was found that the laser irradiation enhanced the NaCl salt rejection and slightly reduced the...
Estimation of nitrogen content in cucumber plant (Cucumis sativus L.) leaves using hyperspectral imaging data with neural network and partial least squares regressions
, Article Chemometrics and Intelligent Laboratory Systems ; Volume 217 , 2021 ; 01697439 (ISSN) ; Pourdarbani, R ; Rohban, M. H ; García Mateos, G ; Arribas, J. I ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In recent years, farmers have often mistakenly resorted to overuse of chemical fertilizers to increase crop yield. However, excessive consumption of fertilizers might lead to severe food poisoning. If nutritional deficiencies are detected early, it can help farmers to design better fertigation practices before the problem becomes unsolvable. The aim of this study is to predict the amount of nitrogen (N) content (mg l−1) in cucumber (Cucumis sativus L., var. Super Arshiya-F1) plant leaves using hyperspectral imaging (HSI) techniques and three different regression methods: a hybrid artificial neural networks-particle swarm optimization (ANN-PSO); partial least squares regression (PLSR); and...
Development of an Evolutionary Algorithm Based on Surrogate Models to be used in Multi-disciplinary Design Optimization of a Flying Vehicle
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
In this research, multi-disciplinary design optimization (MDO) of a flying vehicle has been done based on the flight simulation. A meta-heuristic algorithm called Multi-objective Adaptive Real-coded Memetic Algorithm (MARCOMA) has been used for optimization. Since solving a MDO problem is a time consuming process, a RBF neural network has been used in the optimization algorithm as a surrogate model. The new algorithm, called MARCOMA+NN, has been tested with some standard benchmarks. MDO problem has six disciplines consists structure, aerodynamic, propulsion, guidance, control, and fire control. The MDO problem has 31 design variables and two objective functions. The objective functions are...
Optimal Design and Real-time Implementation of a Cooperative Guidance Algorithm against a Flying Vehicle
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
A cooperative aerial system to defense a Ground Station (GS), against an Incoming aerial Targets (IT) is presented. GS is surrounded by given terrains and a group of homogenous Unmanned Aerial Vehicles (UAVs) are employed using a novel online guidance algorithm in a decentralized manner. The proposed algorithm includes loiter, midcourse and terminal phases. During loiter; UAVs follow an optimal circular path. IT is supposed to approach GS along an optimal low altitude trajectory with respect to the terrains. UAVs are informed the initial position and velocity of IT and they are unaware of IT trajectory. Each UAV decides on whether to engage with IT or not, and shares its decision with other...
Synthesis and Characterization of PVDF Magnetic Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Forounchi, Massoud (Supervisor)
Abstract
PVDF (polyvinylidene fluoride) magnetic nanocomposite films were prepared by solution casting using two types of nanomagnetic particles: (i) magnetic nanoparticles synthesized by using an alkaline solution of mixed ferrous/ferric salts along with oleic acid as a coating agent at 70˚C; (ii) Fe3O4 nanoparticles prepared by hydrolysis of aqueous solution of ferrous/ferric salts with potassium hydroxide at room temprature. Scanning electron microscopy (SEM) showed that the PVDF magnetic nanocomposite had a porous structure with Fe3O4 nanoparticles dispersed inside the porous polymer matrix. The presence of crystalline magnetite within the polymer matrix was confirmed by X-Ray diffraction method...
Cooperative Search and Localization of Mobile RF Ground Targets, Using a Group of UAVs
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
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...
Attitude Control of a 3DOF Quadrotor Stand Using Intelligent Back-stepping Approach
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
In this research a novel intelligent back-stepping control method is developed. This method is robust to sensor noise and external disturbances. In addition, the controller is robust under model uncertainty. This controller does not need precise knowledge of system parameters. This method is based on three methods of: back-stepping control, least squares estimation and a fuzzy compensator. This controller is used to control quadrotor stand witch is like an inverse pendulum. In quadrotor stand modeling, the inverse pendulum effect is considered too, witch is one of the innovations of the research. By doing various simulations, the validity of controller is tested. Also the performance of the...
Cooperative Search and Localization of Aerial Targets, Using a Group of Fixed Wing UAVs
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
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...
A New Method for Integrated Controller and Observer Design of a Nonlinear System Using Genetic Programming
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
The purpose of this paper is to design an integrated controller and observer (ICO) for a nonlinear system using genetic programming. ICO is a function that constructs control command directly from the measured state variables of the system. It means that, this function should imitate the behavior of the observer and controller and control the system with acceptable performance in different initial conditions, at the presence of disturbances and system uncertainties. The complexity of this design method, is not related to the complexity of the plant, in fact, the complexity in plant just effects at run time, but the design procedure does not change. So, if exact model of plant exist, using...
Development of Integrated Model of the Wastewater and Organic Solid Waste Flows to Minimize Environmental Impacts and Maximize Energy Recovery for a Residential Building
, M.Sc. Thesis Sharif University of Technology ; Avami, Akram (Supervisor)
Abstract
Nowdays much of the organic solid waste and wastewater is buried using centralized and traditional methods. This leads to many problems, including groundwater pollution, methane emissions into the atmosphere and rapid transmission of disease. In order to avoid these problems, using a decentralized approach can be a good solution. In this study, recovery of organic waste and wastewater of residential buildings using anaerobic digester as a decentralized way, have been examined. Using experiments, the optimum mass ratio of organic solid waste and wastewater is obtained as 80% and 20% respectively. Biogas production model is developed using mass balance and Balance of electrons in redox...