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A primal-dual interior point method for solving environmental/economic power dispatch problem
, Article International Review of Electrical Engineering ; Volume 6, Issue 3 , 2011 , Pages 1463-1473 ; 18276660 (ISSN) ; Kian, A. R ; Esfahani, M. S ; Sharif University of Technology
2011
Abstract
We proposed a Primal-Dual Interior Point Method (PDIPM) to solve a combined Environmental and Economic Power Dispatch (EEPD) problem. The EEPD problem is a multiobjective problem with competing and non-commensurable objectives. The PDIPM produces a set of nondominated Pareto optimal solutions for the problem. Fuzzy set theory is employed to extract a compromise nondominated solution. The proposed algorithm is applied to the standard IEEE 30 bus six-generator test system. Comparison of our PDIPM results with the various algorithms reported in the literature shows that the solutions of the proposed algorithm are very accurate for the EEPD problem
A Case Study on the Effects of Weather Conditions on Forest Fire Propagation Parameters in the Malekroud Forest in Guilan, Iran
, Article Fire ; Volume 6, Issue 7 , 2023 ; 25716255 (ISSN) ; Norouzi, M ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Multidisciplinary Digital Publishing Institute (MDPI)
2023
Abstract
The present study investigates the effect of climatic parameters, such as air relative humidity and wind speed, on fire spread propagation indexes in the Malekroud Forest, Iran using the FARSITE simulator based on Rothermel’s original fire spread equation. Standard fuel models are used to calibrate the vegetation cover. Sorensen (SC) and kappa ( (Formula presented.) ) coefficients, as well as the Overestimation Index (OI), are used to estimate the simulation’s accuracy. The results confirm that using both ambient condition data and appropriate fuel models is crucial to reaching reasonable results in fire propagation simulations. The values of the Rate of Fire Spread (ROS), Flame Length...
Modified quasi-physical grassland fire spread model: sensitivity analysis
, Article Sustainability (Switzerland) ; Volume 15, Issue 18 , 2023 ; 20711050 (ISSN) ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Multidisciplinary Digital Publishing Institute (MDPI)
2023
Abstract
Developing models for predicting the rate of fire spread (ROS) in nature and analyzing the sensitivity of these models to environmental parameters are of great importance for fire study and management activities. A comprehensive sensitivity analysis of a general and modified quasi-physical model is provided in the current study to predict parameters that affect grassland fire propagation patterns. The model considers radiative heat transfer from the flame and fuel body and convective heat transfer to predict the fire’s rate of spread and the grassland fire patterns. The model’s sensitivity to ten main parameters that affect fire propagation, including temperature, humidity, wind speed,...
Numerical and experimental study of a reversible axial flow fan
, Article International Journal of Computational Fluid Dynamics ; Volume 34, Issue 3 , 2020 , Pages 173-186 ; Mohammadian Bishe, E ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
Reversible axial flow fans, used in tunnel ventilation systems are designed in a way that as the direction of impeller rotation changes, suction and discharge directions change without any sensible change in flow rate and pressure. Also, their reversibility must be higher than 90%. Therefore, the blade profiles of these fans (S-shaped or elliptic) are designed symmetrically. In the current work, a reversible axial flow fan was studied experimentally and numerically in various ambient conditions and blade positions. Additionally, the experimental test of the fan was performed according to the AMCA-210 standard. Comparison of simulation and experimental results indicated the acceptable...
Studying and Modeling Climatic and Terrestrial Factors Effect the Occurrence of Dust Phenomena, and Determining the Origin of Dust Storms in IRAN
,
M.Sc. Thesis
Sharif University of Technology
;
Farhanieh, Bijan
(Supervisor)
Abstract
Particulate matter is an important source of air pollution. Particulate matters have an Undesirable effect on the environment, economic, and the health of Tehran Citizens. Annually, more than 8 thousands of tons of mineral dust from Internal and external resources deposit in Tehran city. In this project, the increase in the level of PM10 concentration during June, 12th to 14th, 2015 have been considered. The intrusion and dispersion of mineral dust during June, 11th to 15h, 2015 have been simulated with the HYSPLIT Model. Also, the Trajectory of particle end in Tehran during the mentioned days simulated and plotted with the HYSPLIT. The results show that more than 85% of PM10 reported by Air...
Attitude Control of a 3DOF Quadrotor Stand Using a Heuristic Nonlinear Controller
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor)
Abstract
A new heuristic controller, called nonlinear model predictive control based on gravitational search algorithm, is proposed for nonlinear systems. Nonlinear model predictive control involves the solution at each sampling instant of a finite horizon optimal control problem subject to nonlinear system dynamics and constraints. The new controller formulates nonlinear model predictive control problem as a single stochastic dynamic optimization problem and uses a system of virtual masses to find the best control signal at each sampling instant. For this purpose, a cost function is defined to evaluate each point of the search space. This function minimizes simultaneously the tracking error, control...
Optimal MIMO waveform design with controlled characteristics
, Article Proceedings International Radar Symposium, 24 June 2015 through 26 June 2015 ; Volume 2015-August , 2015 , Pages 1141-1146 ; 21555753 (ISSN) ; 9783954048533 (ISBN); 9783954048533 (ISBN); 9783954048533 (ISBN) ; Radmard, M ; Nayebi, M. M ; Bastani, M. H ; Rohling, H ; Rohling, H ; Rohling, H ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
In a MIMO (Multiple Input Multiple Output) radar system, proper design of transmit signal and receive filter is an advantageous tool to improve the detection performance. Thus, in this paper, we consider the problem of transmit code and receive filter design, in order to maximize the Signal to Noise Ratio (SNR) at the receiver while enforcing a similarity constraint between the transmit space-time code (STC) and a reference STC which has a desirable ambiguity function. We will show that by solving such constrained optimization problem through successive iterations, our proposed method leads to satisfactory results
A fast and novel method of pattern synthesis for non-uniform phased array antennas
, Article Proceedings International Radar Symposium, 24 June 2015 through 26 June 2015 ; Volume 2015-August , 2015 , Pages 924-929 ; 21555753 (ISSN) ; 9783954048533 (ISBN); 9783954048533 (ISBN); 9783954048533 (ISBN) ; Sebt, M. A ; Nayebi, M. M ; Behroozi, H ; Rohling, H ; Rohling, H ; Rohling, H ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
Weighting elements to achieve radiation patterns with desired characteristics is a classical work in phased array antennas. These characteristics can be low sidelobe level, narrow beamwidth, high directivity, pattern nulling in special angle and etc. For each of these characteristics, different methods have been introduced. Most of methods have been presented for uniform arrays, however there are lots of methods to obtain a desired pattern for antennas with non-uniform element distances. The problem with these methods is complexity or not very good results. In this paper, fast and easy methods based on Least Square Error that leads to good results are presented. In addition, weighting of...
Sustainable solutions for advanced energy management system of campus microgrids: model opportunities and future challenges
, Article Sensors ; Volume 22, Issue 6 , 2022 ; 14248220 (ISSN) ; Javed, H ; Akhter, M. N ; Shahzad, M ; Munir, H. M ; Nadeem, M. U ; Bukhari, S. S. H ; Huba, M ; Sharif University of Technology
MDPI
2022
Abstract
Distributed generation connected with AC, DC, or hybrid loads and energy storage systems is known as a microgrid. Campus microgrids are an important load type. A university campus microgrids, usually, contains distributed generation resources, energy storage, and electric vehicles. The main aim of the microgrid is to provide sustainable, economical energy, and a reliable system. The advanced energy management system (AEMS) provides a smooth energy flow to the microgrid. Over the last few years, many studies were carried out to review various aspects such as energy sustainability, demand response strategies, control systems, energy management systems with different types of optimization...
Atomistic insight into salinity dependent preferential binding of polar aromatics to calcite/brine interface: implications to low salinity waterflooding
, Article Scientific Reports ; Volume 11, Issue 1 , 2021 ; 20452322 (ISSN) ; Badizad, M. H ; Mahani, H ; Dastjerdi, A. M ; Ayatollahi, S ; Ghazanfari, M. H ; Sharif University of Technology
Nature Research
2021
Abstract
This paper resolve the salinity-dependent interactions of polar components of crude oil at calcite-brine interface in atomic resolution. Molecular dynamics simulations carried out on the present study showed that ordered water monolayers develop immediate to a calcite substrate in contact with a saline solution. Carboxylic compounds, herein represented by benzoic acid (BA), penetrate into those hydration layers and directly linking to the calcite surface. Through a mechanism termed screening effect, development of hydrogen bonding between –COOH functional groups of BA and carbonate groups is inhibited by formation of a positively-charged Na+ layer over CaCO3 surface. Contrary to the common...
MIMO ambiguity function optimization through waveform design
, Article Proceedings International Radar Symposium, 24 June 2015 through 26 June 2015 ; Volume 2015-August , 2015 , Pages 333-338 ; 21555753 (ISSN) ; 9783954048533 (ISBN); 9783954048533 (ISBN); 9783954048533 (ISBN) ; Majd, M. N ; Chitgarha, M. M ; Karbasi, S. M ; Nayebi, M. M ; Rohling, H ; Rohling, H ; Rohling, H ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
An important tool for assessing a radar's performance is the ambiguity function. On the other hand, many different schemes have been designed for the transmit waveforms of a MIMO radar. For each one, a criterion has been chosen to improve the performace, e.g. achieving better missed detection. In this paper, considering the ambiguity function as the benchmark, we propose a waveform design scheme, which optimizes the ambiguity function of the MIMO radar system
Laminar falling film flow of aqueous Li Br solution on a horizontal elliptical tube
, Article International Journal of Fluid Mechanics Research ; Volume 40, Issue 4 , 2013 , Pages 324-343 ; 10642277 (ISSN) ; Saidi, M. H ; Sharif University of Technology
2013
Abstract
Flow hydrodynamics of laminar falling film of aqueous Li Br solution (Li Br - H2O) on a horizontal elliptical tube has been investigated in this research. The film velocity distribution and film thickness, namely, the flow characteristics are determined by solving analytically simultaneous simplified Navier - Stokes equations and continuity equation in polar and Cartesian coordinates. The analysis is based on steady state laminar flow of falling liquid film of Li Br - H2O on a horizontal elliptical tube in polar model and Cartesian model (CM), for cases in which traction on the film surface is considered negligible. Models are compared with each other in three cases of aspect ratios (Ar),...
Velocity distributions in (r,θ) directions for laminar flow of a film around horizontal circular tube
, Article 2006 ASME Joint U.S.- European Fluids Engineering Division Summer Meeting, FEDSM2006, Miami, FL, 17 July 2006 through 20 July 2006 ; Volume 1 SYMPOSIA , 2006 , Pages 11-19 ; 0791847500 (ISBN); 9780791847503 (ISBN) ; Saidi, M. H ; Sharif University of Technology
American Society of Mechanical Engineers
2006
Abstract
Velocity distributions in (r,θ) directions are evaluated by solving simultaneous simplified Navier-Stokes equations (NSE) and continuity equation (CE) in polar coordinate. The analysis is based on steady state laminar flow of thin falling liquid film on a horizontal circular tube, for cases in which traction on the film surface is considered negligible. It is a common geometry for part of engineering problems such as evaporator, condenser, absorber, generator of absorption chillers and other similar units in mechanical and chemical engineering. Knowledge of the velocity profiles is usually needed for: 1 - solving governing energy and species equations 2- estimating the average and film...
Velocity distributions in (r,θ) directions for laminar flow of a film around horizontal circular tube
, Article 2006 2nd ASME Joint U.S.-European Fluids Engineering Summer Meeting, FEDSM 2006, Miami, FL, 17 July 2006 through 20 July 2006 ; Volume 2006 , 2006 ; 0791837831 (ISBN); 9780791837832 (ISBN) ; Saidi, M. H ; Sharif University of Technology
2006
Abstract
Velocity distributions in (r,θ) directions are evaluated by solving simultaneous simplified Navier-Stokes equations (NSE) and continuity equation (CE) in polar coordinate. The analysis is based on steady state laminar flow of thin falling liquid film on a horizontal circular tube, for cases in which traction on the film surface is considered negligible. It is a common geometry for part of engineering problems such as evaporator, condenser, absorber, generator of absorption chillers and other similar units in mechanical and chemical engineering. Knowledge of the velocity profiles is usually needed for: 1- solving governing energy and species equations 2- estimating the average and film...
An experimental investigation of foam for gas mobility control in a low-temperature fractured carbonate reservoir
, Article Petroleum Science and Technology ; Volume 30, Issue 10 , 2012 , Pages 976-985 ; 10916466 (ISSN) ; Kharrat, R ; Motealleh, M ; Khanamiri, H. H ; Nematzadeh, M ; Ghazanfari, M. H ; Sharif University of Technology
2012
Abstract
This work concerns the experimental investigation of surfactant alternating CO 2 injection in carbonate rocks. The core samples provided from a low-temperature fractured light oil reservoir, located in southwest Iran. The experiments were designed to observe the effect of CO 2-foam injection on gas mobility and oil recovery at different surfactant concentrations. The core samples were initially saturated with synthetic/field brine, 5,000 ppm, and then flooded with live oil to reach connate water saturation at reservoir condition, 115F and 1,700 psia. The commercial surfactant used was sodium lauryl sulfate as an anionic surfactant. The results of this work, along with field-scale simulation...
Study of behavior of two phase flow in vertical large diameter pipe
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 7, Issue PARTS A AND B , November , 2010 , Pages 1735-1741 ; 9780791844441 (ISBN) ; Karrabi, H ; Rezasoltani, M ; Saidi, M. H ; Sharif University of Technology
2010
Abstract
Knowledge of Air-water two phase flows is significant to different engineering systems such as chemical reactors and power plant and petrochemical and petroleum industry. One of the most industrial cases of two phase flow is two phase flow in vertical large pipes. In this paper in order to find two phase flow behavior along vertical large diameter pipes we simulate air inlets with different number of holes and different hole diameters in the same flow rate of air. In addition, flow characteristics such as cross-sectional void fraction and velocity and pressure were considered. To achieve this aim, main equations of flow have been developed for investigation of flow behavior in air-water two...
Experimental investigation of an open loop pulsating heat pipe using ferrofluid
, Article ASME 2012 3rd International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2012 ; 2012 , Pages 175-184 ; 9780791854778 (ISBN) ; Taslimifar, M ; Saidi, M. H ; Shafii, M. B ; Afshin, H ; Saimak, K. H ; Sharif University of Technology
2012
Abstract
The present work investigates the thermal performance of a five turn Open Loop Pulsating Heat Pipe (OLPHP). The effects of working fluid namely water and ferrofluid, heat input, ferrofluid concentration, charging ratio, and orientation will be considered. Experimental results show that using ferrofluids can enhance the thermal performance in comparison with the case of distilled water. In addition, applying a magnetic field on the OLPHP charged with ferrofluid reduces its thermal resistance. Variation of the ferrofluid concentration results in different thermal performance of the OLPHP. Best charging ratio for the distilled water and ferrofluid without magnetic field is 60 % in most of the...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; 2019 ; 09484280 (ISSN) ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer Tokyo
2019
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; 2019 ; 09484280 (ISSN) ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer Tokyo
2019
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...
Challenges in calculation of critical buckling load of tubular members of jacket platforms in finite element modeling
, Article Journal of Marine Science and Technology (Japan) ; Volume 25, Issue 3 , 2020 , Pages 866-886 ; Erfani, M. H ; Sayyaadi, H ; Sharif University of Technology
Springer
2020
Abstract
Accurate estimation of the capacity curve of offshore jacket structures to achieve performance levels and ductility is of great importance. Proper modeling of compressive members to correctly investigate global and local buckling is crucial in estimation of the capacity curve. Buckling modes and deformations due to local buckling can be considered, if the compressive braces are modeled by shell or solid elements. The purpose of this paper is to achieve the correct compressive behavior of braces with solid type elements and investigate the effects of five different parameters such as D/t, L/D, mesh size, mesh size ratio, and imperfections. ABAQUS FE software is used for this purpose. The...