THD Analysis in Closed-Loop Analog PWM Class-D Amplifiers

P. Amiri; M. Kohestani; M. Seifouri

Volume 2, Issue 1 , January 2014, , Pages 1-5

  In this paper, we investigate the parameters affecting Total Harmonic Distortion (THD) and Power Supply Rejection Ratio (PSRR) in PWM Class D Amplifiers (CDAs) on the basis of linear models with feedback. From our mathematical analysis, we show that the THD of a PWM Class D amplifier with feedback can ...  Read More

ABCD matrix for reflection and refraction of laser beam at tilted concave and convex elliptic paraboloid interfaces and studying laser beam reflection from a tilted concave parabola of revolution

M. Mansour Abadi; Z. Ghassemlooy; D. Smith; W. Pang Ng

Volume 3, Issue 1 , January 2015, , Pages 1-11

  Studying Gaussian beam is a method to investigate laser beam propagation and ABCD matrix is a fast and simple method to simulate Gaussian beam propagation in different mediums. Of the ABCD matrices studied so far, reflection and refraction matrices at various surfaces have attracted a lot of researches. ...  Read More

Fuzzy Neighbor Voting for Automatic Image Annotation

V. Maihami; F. Yaghmaee

Volume 4, Issue 1 , January 2016, , Pages 1-8

  With quick development of digital images and the availability of imaging tools, massive amounts of images are created. Therefore, efficient management and suitable retrieval, especially by computers, is one of themost challenging fields in image processing. Automatic image annotation (AIA) or refers ...  Read More

Cognitive Radio Networks
Joint Improvement of Spectral and Energy Efficiency in Energy Harvesting Based Cognitive Radio Networks

M. Sadeghian Kerdabadi; R. Ghazizadeh; H. Farrokhi

Volume 10, Issue 1 , January 2022, , Pages 1-16

  Background and Objectives: In an energy harvesting cognitive radio network, both energy efficiency and spectrum efficiency can be improved, simultaneously. In this paper, we consider an energy harvesting-based multi-antenna cognitive radio network to execute cooperative spectrum sensing, data transmission ...  Read More

Indoor Non-directed Optical Wireless Communications Optimization of the Lambertian Order

F. Ghassemlooy; D. Wu; M.A. Khalighi; X. Tang

Volume 1, Issue 1 , January 2013, , Pages 1-10

  For an indoor non-directed line of sight optical wireless communication (NLOS-OWC) system we investigate the optimized Lambertian order (OLO) of light-emitting diodes (LEDs). We firstly derive an expression for the OLO from a conventional Lambertian LED model. Then, we analyze the indoor multi-cell NLOS-OWC ...  Read More

An Improvement over Random Early Detection Algorithm: A Self-Tuning Approach

S. Jamali; N. Alipasandi; B. Alipasandi

Volume 2, Issue 2 , July 2014, , Pages 57-61

  Random Early Detection (RED) is one of the most commonly used Active Queue Management (AQM) algorithms that is recommended by IETF for deployment in the network. Although RED provides low average queuing delay and high throughput at the same time, but effectiveness of RED is highly sensitive to the RED ...  Read More

Fuzzy Logic Based Life Estimation of PWM Driven Induction Motors

T. G. Arora; M. V. Aware; D. R. Tutakne

Volume 1, Issue 2 , July 2013, , Pages 63-71

  Pulse-width modulated (PWM) adjustable frequency drives (AFDs) are extensively used in industries for control of induction motors. It has led to significant advantages in terms of the performance, size, and efficiency but the output voltage waveform no longer remains sinusoidal. Hence, overshoots, high ...  Read More

Design and PLC Implementation for Speed Control of DC Motor using Fuzzy Logic

J. Rostami Monfared; M. Fazeli; Y. Lotfi

Volume 3, Issue 2 , July 2015, , Pages 71-75

  In this article, a speed control of DC motor is designed and illustrated using fuzzy logic-based programmable logic controller (PLC). The DC motor is an attractive part of electrical equipment in many industrial applications requiring variable speed and load specifications due to its ease of controllability. ...  Read More

Diagnosis of Heart Disease Based on Meta Heuristic Algorithms and Clustering Methods

S. Roostaee; H.R Ghaffary

Volume 4, Issue 2 , July 2016, , Pages 105-110

  Data analysis in cardiovascular diseases is difficult due to large massive of information. All of features are not impressive in the final results. So it is very important to identify more effective features. In this study, the method of feature selection with binary cuckoo optimization algorithm is ...  Read More

Nonlinear System
Nonlinear Analysis of Colpitts Oscillator using on Differential Transform Method

A.R. Ghomi Taheri; F. Setoudeh; M. B. Tavakoli

Volume 9, Issue 2 , July 2021, , Pages 127-142

  Background and Objectives: The Differential transform method (DTM) is used in the analysis of ordinary, partial, and high-order differential equations. Recently, the DTM is used in the nonlinear analysis of physical nonlinear dynamic systems.Methods: The DTM method is used to analyze and analytically ...  Read More

Network Security
An Advanced Hybrid Honeypot for Providing Effective Resistance in Automatic Network Generation

M. Amiri; A. Barati

Volume 7, Issue 2 , July 2019, , Pages 133-144

  Background and Objectives: Increasing usage of Internet and computer networks by individuals and organizations and also attackers’ usage of new methods and tools in an attempt to endanger network security, have led to the emergence of a wide range of threats to networks.Methods: A honeypot is one ...  Read More

Wireless Sensor Network
Depuration‎ based Efficient Coverage Mechanism for ‎Wireless Sensor Network

S. Ashraf; T. Ahmed; Z. Aslam; D. Muhammad; A. Yahya; M. Shuaeeb

Volume 8, Issue 2 , July 2020, , Pages 145-160

  Background and Objectives: The quick response time and the coverage range are the crucial ‎factors by which the quality service of a wireless sensor network ‎can be acknowledged. In some cases, even networks possess ‎sufficient available bandwidth but due to coverage tribulations, the ‎customer ...  Read More

A Comparative Study on Anonymizing Networks: TOR, I2P, and Riffle Networks Comparison

M. Hosseini Shirvani; A. Akbarifar

Volume 10, Issue 2 , July 2022, , Pages 259-272

  Background and Objectives: Among miscellaneous networks, onion-based routing network technologies such as The Onion-based Routing (ToR), Invisible Internet Project (I2P), and Riffle networks are used to communicate anonymously by different worldwide users for security, privacy, and safety requirements. ...  Read More

Design, Simulation and implementation of active dual-band dipole antenna using a series stub

M. Zahiry; S.M. Hashemi; J. Ghalibafan

Volume 5, Issue 1 , January 2017, , Pages 1-6

  In this paper, a new method for designing an active dual-band dipole antenna is proposed. The operating frequencies of the proposed antenna are 150 and 450 MHz that are usually used in military applications. Using a series stub is the main idea in the proposed dual-band antenna, where it makes an independent ...  Read More

A Simple and Fast Method for Field Calibration of Triaxial Gyroscope by Using Accelerometer

S. Ranjbaran; A. Roudbari; S. Ebadollahi

Volume 6, Issue 1 , January 2018, , Pages 1-6

  Background and Objectives: Using field calibration methods without precision laboratory equipment, systematic faults of inertial sensors can be reduced and measurement accuracy can be increased. Methods: In this paper, a simple and fast method called improved least squares is used to find calibration ...  Read More

Voltage Control and Load Sharing in a DC Islanded Microgrid Based on Disturbance Observer

H. Amiri; G. Arab Markadeh; N. Mahdian

Volume 7, Issue 1 , January 2019, , Pages 1-10

  Background and Objectives: Increasing DC loads along with DC nature of distributed energy resources (DERs) raises interest to DC microgrids. Conventional droop/non-droop power-sharing in microgrids suffers from load dependent voltage deviation, slow transient response, and requires the parameters of ...  Read More

A-New-Closed-form-Mathematical-Approach-to-Achieve Minimum Phase Noise in Frequency Synthesizers

S. SamadiGorji; B. Zakeri; M.R. Zahabi

Volume 2, Issue 1 , January 2014, , Pages 7-13

  The aim of this paper is to minimize output phase noise for the pure signal synthesis in the frequency synthesizers. For this purpose, first, an exact mathematical model of phase locked loop (PLL) based frequency synthesizer is described and analyzed. Then, an exact closed-form formula in terms of synthesizer ...  Read More

MOCA ARM: Analog Reliability Measurement based on Monte Carlo Analysis

S. Taghipour; R. Niaraki Asli

Volume 4, Issue 1 , January 2016, , Pages 9-14

  Due to the expected increase of defects in circuits based on deep submicron technologies, reliability has become an important design criterion. Although different approaches have been developed to estimate reliability in digital circuits and some measuring concepts have been separately presented to reveal ...  Read More

3D Hand Motion Evaluation Using HMM

A. Safaei; M. Jahed

Volume 1, Issue 1 , January 2013, , Pages 11-18

  Gesture and motion recognition are needed for a variety of applications. The use of human hand motions as a natural interface tool has motivated researchers to conduct research in the modeling, analysis and recognition of various hand movements. In particular, human-computer intelligent interaction has ...  Read More

FSR Decrement and Coupling Coefficient Increment in Add-Drop Filters

E. Rafiee; F. Emami

Volume 3, Issue 1 , January 2015, , Pages 13-16

  In this paper, effects of the structural parameters on the optical characteristics of an add-drop filter, consisting of two straight waveguides and a micro-ring resonator (MRR), have been investigated. In this research, effects of MRR radius, the width of MRR and waveguide and the gap between MRR and ...  Read More

Electrical Machines
Modeling and Analysis of Flat Double-sided Linear Permanent Magnet Synchronous Generator by Magnetic Equivalent Circuit

S. Niknafs; A. Shiri; S. Bagheri

Volume 10, Issue 1 , January 2022, , Pages 17-24

  Background and Objectives: In recent years, linear generators have been broadly utilized to harness wave motion energy. There are various types of linear generators with different magnetic and geometric structures. Among these generators, linear permanent magnet synchronous generator provides a higher ...  Read More

Bidding Strategy in Spot Markets with Definition of a New Market Power Index by Using Conjectural Variation

M. Hafezi_Nasab; M. Rashidinejad; A. Abdollahi; I. Taheri

Volume 2, Issue 2 , July 2014, , Pages 63-68

  In this paper, the concept of Conjectural Variation (CV) is used to specify optimal generation decision for generation companies (Gencos). The conjecture of Genco is defined as its belief or expectation about the reaction of rivals to change of its output. Using CV method, each Genco has to learn and ...  Read More

A High Efficiency Low-Voltage Soft Switching DC–DC Converter for Portable Applications

P. Amiri; M. Sharafi

Volume 1, Issue 2 , July 2013, , Pages 73-81

  This paper presents a novel control method to improve the efficiency of low-voltage DC-DC converters at light loads. Pulse Width Modulation (PWM) converters have poor efficiencies at light loads, while pulse frequency modulation (PFM) control is more efficient for the same cases. Switching losses constitute ...  Read More