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A fuzzy random minimum cost network flow programming problem [electronic resource]
, Article Journal of Industrial and Systems Engineering (JISE)-Iranian Institute of Industrial Engineering ; Article 3, Volume 6, Issue 1, Spring 2012, Page 34-47 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept
Special classes of mathematical programming models with fuzzy random variables [electronic resource]
, Article Journal of Intelligent and Fuzzy Systems, Published In: IOS Press ; Volume 19, Number 2, 2008 ; Nematian, Javad ; Sharif University of Technology
Abstract
In this paper, we will discuss two special classes of mathematical programming models with fuzzy random variables. In the first model, a linear programming problem with fuzzy decision variables and fuzzy random coefficients is introduced. Then an algorithm is developed to solve the model based on fuzzy optimization method and fuzzy ranking method. In the second model, a fuzzy random quadratic spanning tree problem is presented. Then the proposed problem is formulated and solved by using the scalar expected value of fuzzy random variables. Furthermore, illustrative numerical examples are also given to clarify the methods discussed in this paper
A special class of fuzzy integer programming model with all different constraints [electronic resource]
, Article Scientia Iranica ; Vol. 16, No. 1, pp. 1-10, 2009 ; Nematian, Javad ; Sharif University Of Technology
Abstract
In this paper, a fuzzy approach is applied to special classes of integer programming problems with all diierent constraints. In the rst model, a fuzzy integer programming model is developed to represent the all-diierent constraints in mathematical programming. In order to solve the proposed model, a new branching scheme for the Branch and Bound algorithm is also presented. In the second model, a special class of large-scale multi-objective fuzzy integer programming problems with all-diierent constraints is introduced. A solution method for the proposed model is also developed by using the decomposition technique, weighting method and Branch and Bound algorithm. An illustrative numerical...
Fuzzy random minimum cost network problem [electronic resource]
, Article Journal of Industrial and Systems Engineering ; Vol. 6, No. 1, pp 34-47, 2012 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept
Theoretical study of borazine: cation-π (Be 2+, Mg 2+, and Ca 2+) interaction
, Article Structural Chemistry ; 2012 , Pages 1-7 ; 10400400 (ISSN) ; Sharif University of Technology
2012
Abstract
The geometries of the complexes of Be 2+, Mg 2+, and Ca 2+ metal cations with borazine ring were studied. The complexes were optimized at the B3LYP level and the 6-311++G(d,p) basis set. Then, the interaction energies corrected by basis set super position error were calculated in the same level. The results show that interaction energy is strongly dependent on the charge-to-size ratio of the cation. Therefore, Be 2+ cation has the most interaction energy value with respect to Mg 2+ and Ca 2+ metal cations. Natural bond orbital analysis was performed to calculate the charge transfer and natural population analysis of the complexes. Quantum theory of atoms in molecules was also applied to...
Experimental Study of Common Refrigerants Replacement with Hydrocarbon Mixture in Automotive Air Conditioning System
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor)
Abstract
Due to the environmental concern for the harmful effect of the release of HFCs on global warming there has been more interest for the use of hydrocarbons as refrigerants in recent years. In this project the performance of these refrigerants have been studied and compared with common refrigerants from the quantitative and qualitative point of view using a real-scale model of Peugeot-405 air conditioning system. Charging amount, inside temperature, cooling load, energy consumption of cycle, coefficient of performance and required time to steady state condition are the important comparative criteria for such a study. After carrying out a series of tests it has been considered that charge...
A Metabonomics Study of Samples of Different Diseases: Investigation of Linear and Non-Linear Model by Nuclear Magnetic Resonance
, Ph.D. Dissertation Sharif University of Technology ; Tafazzoli, Mohsen (Supervisor)
Abstract
Metabonomics is a quantitative measurement of time dependent metabolic interactions for living systems in response to the pathological or genetic variations. NMR spectroscopy has emerged as a key tool for understanding metabolic processes in living systems. In this project, the study of metabolomics was performed as classification and regression on samples of parkinson’s disease, multiple sclerosis disease, celiac disease and crohn’s disease. In classification part, various methods were applied using optimal parameters.classification methods in Parkinson’s disease, multiple sclerosis disease, celiac disease and crohn’s disease were RF, CART, PLS-DA, RF and RF respectively. Based on the...
groundwater level fluctuations forecasting using conjunction models of Wavelet - Neural-Fuzzy Network (WNF) and Wavelet-Neural Network (WNN) and linear model of ARIMA (case study: Qom plain
,
M.Sc. Thesis
Sharif University of Technology
;
Shamsaei, Abolfazl
(Supervisor)
Abstract
Prediction of groundwater level fluctuations is absolutely necessary for the proper manag ement of these precious resources. There are different methods to predict hydrological time series such as groundwater level. Linear models inefficiency in predicting nonlinear and n on-stationary time series cause researchers widely use artificial intelligence techniques such as Artificial Neural Networks (ANN), Fuzzy Inference System (FIS), Genetic Algorithm (GA) and their hybrid models such as Artificial Neural – Fuzzy Inference System (ANFIS). These smart models are capable to simulate nonlinear and non-stationary time series in suitable accu-racy using by a few time and data. By emersion of Wavelet...
Numerical Modeling of Rocking Of Shallow Foundations Subjected to Slow Cyclic Loading with Consideration of Soil-Structure Interaction
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Foundation is the lowest load-bearing part of a structure and a part of underneath soil that is affected by the structure load. In fact, foundation transfers the loads from the superstructure to the substructure, preventing excessive settlement of soil or stresses exceeding soil bearing capacity. Indeed, almost all structures are placed on the ground, therefore the effects of soil and structure on each other, which is known as Soil Structure Interaction (SSI), is considered as a key factor in many important and engineered structures. In contrast to structures on a rigid footing, a flexible foundation may show stiffness degradation along with an increase of damping and natural period of the...
A new model for deformed carbon nanotubes using Green's function
, Article Applied Physics A: Materials Science and Processing ; Volume 105, Issue 4 , 2011 , Pages 875-880 ; 09478396 (ISSN) ; Sarvari, R ; Sharif University of Technology
2011
Abstract
A new method for modeling and analysis of deformed carbon nanotubes (CNTs) using Green's function, is presented in this paper, for the first time. Using the proposed method, a new circuit model is obtained for the deformation region of a deformed single-walled CNT (SWCNT), which the values of its elements depend on the type of deformation and also the deformation parameters such as the coupling matrices and the energy variations of deformation region. The comparison between the obtained results from the analysis of proposed model and the literature gives a good match which approves the accuracy and correctness of the proposed model
Controller Design to Reduce Effects of Radome Error Slope on the Stability of Misssile
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor)
Abstract
In this project three models addressed before in the references are reviewed and the stability margins of radome error slope obtained by analytical method. Then a new model who is usefull in practical applications presented. Because of complication of this model the model is simplified and stability margins for radome error slope derived in simplified model. It is also shown that simplified applicative model is similar to model purposed in ref. [6]. Then a PD controller designed to stabilize some of models reviewed in chapter 3. The equations derived before verified in continuation of the project. The effects of parameters on the stability of missile analysed by equations derived in chapter...
Transfer Alignment Algorithm Development for Aerial Launch Space Launch Vehicle Navigation System Using the Carrying Airplane Navigation System
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor)
Abstract
In this research the problem is the development and simulation of Transfer Alignment algorithm for an aerial launch space launch vehicle. In the references there is no complete study on development of this algorithm for the case space launch vehicle. In order to develop the algorithm, the carrying airplane and the space launch navigation systems are considered as the Master INS and Slave INS respectively. First a 6DOF simulation of the airplane is presented. Then the desired inputs for simulation of Master and Slave INS are generated. Also the differences of the inputs of Slave INS caused by the distance between the Master and Slave INS is considered. Master INS performs as an ideal INS and...
Design of an Optimal Site Deployment Procedure in Different Air-Defense Scenarios
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor)
Abstract
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...
Context-Specific Reconstruction and Gap-Filling of Metabolic Networks by Sparse Reconciliation of Data Inconsistencies
, M.Sc. Thesis Sharif University of Technology ; Tefagh, Mojtaba (Supervisor)
Abstract
With the increasingly collected biological data, appropriate usage of this data is of great importance for understanding and predicting biological systems and has been the aim of experiments and data collections. A famous category of biological data is known as “omics” which refers to transcriptomics, proteomics, metabolomics, and fluxomics, from different cells or tissues in various media and conditions. This set of data is regularly used for tasks such as studying cells and organisms, understanding cell states, cancer prediction, etc. and is of great importance in Systems Biology.In this thesis, we concentrate on studying cells or organisms using such data, where during that process, we...
Borsuk–Ulam Theorem and an Introduction to Topological Combinatorics
, M.Sc. Thesis Sharif University of Technology ; Jafari, Amir (Supervisor)
Abstract
Topological combinatorics is an almost novel branch in mathematics whose dawn began to shine originally from Lovász studies at late 70's. The main purpose of the pursued subjects in this branch is to apply topological methods in order to conclude various combinatorial results based on the famous Borsuk-Ulam's theorem which itself is a very deep statement in algebraic topology and has many equivalent versions. For instance, one of these versions states that there is no continuous map f:S^n⟶S^(n-1) which behaves antipodally. In this thesis, we intend to take a considerably long journey in homology theory to pave the way toward a complete proof of this theorem and some of its generalizations....
Production of Uranium Dioxide Nano Powder With Hydrothermal Method in Supercritical Water Reactor
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Ahmadi, Javad (Supervisor) ; Karimi Sabet, Javad (Co-Advisor)
Abstract
Hydrothermal supercritical method is one of the most suitable methods for metal oxide nano powder, ceramics and mineral catalyst synthesis. Metal oxides nanopowder in its pure or mixed form has wide potential application as chemical industrial catalyst, hot Superconductors, magnetic material, gas sensors and car catalyst convertors. One of the most important metal oxides aspects of application is uranium oxide as nuclear reactor fuel is used. In addition, UO2 is selective catalyst for converting methane to methanol process and Decomposition of organic Chlorine material. In Supercritical hydrothermal method done in high pressure reactor with critical to fluid, is new method for the...
A Dynamic Slack Management Technique for Low Energy Consumption in Real-time Multi-core Embedded Systems
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
Due to the increasing development of digital systems based on limited energy sources (i.e. battery), energy efficiency has become one of the most important concerns in the design of these systems. The use of multi-core architecture is an effective solution for the problem of reducing energy consumption. Hence using it in digital systems has become more common. In addition, enabling methods for reducing energy consumption on processor, helps in making energy more efficient. DVFS and DPM are the two major methods used for reducing dynamic and static energy consumption of processors. The using of multi-core architecture due to the higher chip density, results the static and dynamic energy...
Integrated Adaptive Nonlinear Guidance and Control Applied toan Agile Vehicle
, M.Sc. Thesis Sharif University of Technology ; Fathi, Mohsen (Supervisor)
Abstract
Integrated guidance and control (IGC) as a new approach to guidance and control methods has been studied in this thesis. A new approach to nonlinear aerodynamic formulation with backstepping controller has been proposed in order to improve interception. Various curve fitting techniques like Gram-schmidt method has been tested. But finally a planar aerodynamic formulation was used which only varies with angle of attack. Results showed that the proposed method requests smaller control input than the linear IGC formulation and conventional G&C methods, because of more precise knowledge of normal force coefficient. Thus the vehicle experiences smaller angle of attack and normal acceleration....
Performance Analysis and Consideration of Steel Shear Walls and Bracing in Irregular Plans of Mid-rise and High-rise Structures
, M.Sc. Thesis Sharif University of Technology ; Mofid, Masoud (Supervisor)
Abstract
Plan irregularities of structures due to the governing regional and environmental conditions are a pretty important issue from the architectural as well as structural design point of view. Most of the time, especially in mid-rise and/or high-rise buildings with plan irregularities, dual system of Moment Resisting Frames (MRF), accompanied with shear walls are strongly suggested. Considering the previous works and investigations of researchers, reveals not too many studies and researches in this regards; specially, when it comes into new area and application of the Steel Shear Walls (SSW). In the present work, at first it is proposed to model and analyze a MRF steel structure with plan...
Magnetoresistance due to domain wall bulging
, Article Journal of Magnetism and Magnetic Materials ; Volume 322, Issue 16 , August , 2010 , Pages 2401-2404 ; 03048853 (ISSN) ; Phirouznia, A ; Sharif University of Technology
2010
Abstract
The effect of bulging of domain wall (DW) on the magnetoresistance (MR) is investigated. With taking into account the auto-correlation between the points of the interface, one can formulate the mobility within the relaxation time approximation scheme. The results show that the bulging of DW, evaluated with the commonly accepted magnetic parameters for typical ferromagnetic materials of Co, Fe and Ni, has a countable role into the MR