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Wavelet Applications in Pattern Recognition

, M.Sc. Thesis Sharif University of Technology Piri Pishekloo, Bijan (Author) ; Mahdavi Amiri, Nezameddin (Supervisor)

Abstract

We study wavelet transformation for use in pattern recognition. Feature extraction is a crucial processing step for pattern recognition. Feature extraction is based on finding mathematical methods for reducing dimensionality of pattern representation. Two most important features to be extracted are edges and textures. Edges and textures are not absolute concepts and change with scale. Moreover, local characteristics of edges are needed. In recent decades, wavelet transformation as a mathematical tool has captured the attention of many scientists in signal processing and mathematics. Wavelet basis can provide efficient and useful description of a function or signal since it has local...

Numerical Investigation of Nano-Particles Dispersion and Deposition in Crossing of Elliptical Obstacles Networkusing Lattice Boltzmann Method

, M.Sc. Thesis Sharif University of Technology Piri, Salman (Author) ; Moosavi, Ali (Supervisor)

Abstract

Investigation of transport and deposition of aerosol particles has been of interest to researchers in many branches of science. Various numerical and experimental methods has been utilized in particulate fluid flows studies. In recent relevant researches lattice Boltzmann method has been widely used and is reported to be a robust and efficient method. In present study, numerical investigation of dispersion and deposition of aerosol particles is studies in the channel, containing elliptical obstacles geometry using Lattice Boltzmann Method. Fluid flow simulations are performed using LBM while for the study of particle transport and deposition, tracking and the motion equations of them,...

Design and Implementation of 6-18 GHz Driver Amplifier

, M.Sc. Thesis Sharif University of Technology Piri, Milad (Author) ; Medi, Ali (Supervisor)

Abstract

Nowadays, application of microwave integrated circuits in commerce and humanitarian military measures plays an important role. When integrated microwave circuits emerged, the dream of producing high quality and low cost amplifiers and mass productionhas been fulfilled. Power amplifiers which are the last block in a communication systemare one of the most important circuits in this field.
Since driver amplifiers are interstage between high and low power sections of a system, should have good specificationsfor both small and large signal analysis. Thus, designing such a circuit can be very challenging. In order to get the desired bandwidth, high-order filters are used as interstage...

Studying the Role of Distraction of Men and Women in Accidents Using Structural Equation Modeling

, M.Sc. Thesis Sharif University of Technology Piri, Mehran (Author) ; Kermanshah, Mohammad (Supervisor)

Abstract

Crash severity is among the fundamental safety indicators in transportation. In recent years, distracted driving has been one of the biggest concerns in road crashes. Many scholars have evaluated the effects of distraction in crash severities and injuries. This study uses the latest general estimates system (GES) crash dataset, which is a subset of the US National Automotive Sampling System (NASS) and the structural equation model (SEM) approach to explore the relationships between distraction factors and crash severity in male and female drivers. Using SEM for modeling about 22 thousand observations offers the opportunity to simultaneously examine complex relationships between variables by...

Integrated Dynamic Pricing and Ordering in a Supply Chain With Demand Learning

, M.Sc. Thesis Sharif University of Technology Piri, Saeed (Author) ; Modarres Yazdi, Mohammad (Supervisor)

Abstract

In this study, four pricing models in a supply chain are developed. The first model includes a retailer. The second model also includes a retailer. However in this model we apply the learning technique to update the stochastic demand. In the third model, we consider a supply chain consisting of a retailer and a manufacturer. Finally, in the fourth model we consider a supply chain consisting of a retailer and a manufacturer and like the second model; we apply the learning technique to update the stochastic demand. In all models we assume that a single product is sold in a monopoly market. In this study we seek to simultaneously determine decisions about production, pricing and ordering to...

Novel Approach Towards Mechanical and Thermal Resistant Capillary Microextraction by Sol-Gel Technique in On-Line Combination with High Performance Liquid Chromatography

, Ph.D. Dissertation Sharif University of Technology Piri-Moghadam, Hamed (Author) ; Bagheri, Habib (Supervisor)

Abstract

In this thesis, a new approach was developed to achieve mechanical and chemical resistant capillary microextraction (CME) in on-line combination with high performance liquid chromatography (HPLC) based on sol-gel technology. This thesis is divided into three chapters:
First chapter contains of two parts. Overcoming the lack of mechanical stability of the substrate of CME by replacing the fused silica by copper tubings was the main objective of the first part. Self-assembled monolayers technique was employed to functionalize the copper tube followed by chemical bonding of the sorbent on the inner surface of the copper tube by sol-gel technology. The prepared copper tube containing the...

An approach for refining JML specification to object oriented code

, Article 2009 14th International CSI Computer Conference, 20 October 2009 through 21 October 2009 ; 2009 , Pages 1-9 ; 9781424442621 (ISBN) Piri, R ; Mirian Hosseinabadi, S. H ; Sharif University of Technology

2009

Abstract

JML is a behavioral interface specification language which has Java as its target implementation language. It combines the idea of using Java expressions from Eiffel language with the model-based approach to specify a program. Refinement calculus is a framework to produce executable code from a specification by preserving the correctness of programs. In this paper some constructs of JML concerning object creation, feature call, exceptional behavior and concurrency constructs are studied and some refinement rules are proposed to obtain an object oriented code in Java from a JML specification containig these constructs. The correctness of these rules is proved by weakest precondition predicate...

Simulation of the Influence of Hypertension on Low Density Lipoprotein (Ldl) Permeation into Multilayer Coronary Bifurcation

, M.Sc. Thesis Sharif University of Technology Moniri Piri, Mohammad (Author) ; Firoozabadi, Bahar (Supervisor)

Abstract

Atherosclerosis, due to the penetration of low-density lipoprotein particles (LDL) into the arterial wall, is one of the most common and death-leading diseases in today's world. Due to its importance, extensive research has been conducted on the factors that affect this disease. In this thesis, a numerical study of the effects of Wall Shear Stress (WSS), non-Newtonian behavior of blood, different hematocrit values, and blood pressure on LDL permeation through the artery wall layers are investigated in a 4-layer wall model of a coronary bifurcation. To obtain the velocity and concentration fields in the domain, momentum, Brinkman, and mass transport equations are solved in the lumen and wall...

Refning Object Oriented Formal Specifcation To Object Oriented Code

, M.Sc. Thesis Sharif University of Technology Piri, Razieh (Author) ; Mirian Hosseinabadi, Hassan (Supervisor)

Abstract

The presented work provides a calculus for refining an object oriented formal specification to an object oriented code. A refinement calculus provides a framework to produce executable code from a specification while preserving its correctness. Eiffel Refinement Calculus is the most complete work in this domain which is studied in this research.
The Formal specification language which is considered for this purpose is .JML to specify executable code in .Java language. For this calculus some refinement laws are pre- sented and their proofs is given by weakest precondition predicate transformer, a work which was not considered in Eiffel Refinement Calculus. The constructs which are used in...

On-line micro solid-phase extraction of clodinafop propargyl from water, soil and wheat samples using electrospun polyamide nanofibers

, Article Chromatographia ; Vol. 77, issue. 9-10 , May , 2014 , p. 723-728 Bagheri, H ; Asgari, S ; Piri-Moghadam, H ; Sharif University of Technology

2014

Abstract

An on-line extraction/determination set up was designed for micro solid-phase extraction of clodinafop propargyl from water, soil and wheat samples using electrospun polyamide nanofiber mats. The prepared mats were packed in a stainless steel tube which conveniently acted as a high-performance liquid chromatography injection loop. Influential parameters affecting the extraction efficiency were optimized using a distilled water sample fortified with 25 μg L-1 of clodinafop propargyl. An enrichment factor of 440 was achieved for clodinafop propargyl indicating the ability of the whole procedure. Under the optimum conditions, the linearity for the analyte was in the range of 6-700 μg L-1, while...

Grafting the sol-gel based sorbents by diazonium salts: A novel approach toward unbreakable capillary microextraction

, Article Journal of Chromatography A ; Volume 1318 , November , 2013 , Pages 58-64 ; 00219673 (ISSN) Bagheri, H ; Bayat, P ; Piri Moghadam, H ; Sharif University of Technology

2013

Abstract

The present work deals with a novel approach for grafting a sol-gel based sorbent, using diazonium salts for preparation of an unbreakable capillary microextraction (CME) device in on-line combination with high performance liquid chromatography (HPLC). The use of diazonium salts modifier allowed all types of metallic and non-metallic substrates to be used without any limitation. Substrates including copper, brass, stainless steel and polytetrafluoroethylene (PTFE) were chosen to be functionalized by chemical or electrochemical reduction of 4-amino phenyl acetic acid. Then, 3-(trimethoxysilyl)propylamine (3TMSPA) was selected as the precursor and the only reagent for preparation of the...

Design of a Fault Tolerant SPARC Based Micro Processor On FPGA

, M.Sc. Thesis Sharif University of Technology Hosseini, Morteza (Author) ; Rashidian, Bijan (Supervisor) ; Vosoughi Vahdat, Bijan (Supervisor)

Abstract

In this thesis, LEON Processor was chosen for its compatible architecture that can be implemented on a wide range of FPGAs. The final designed processor is aimed to conquer soft and hard errors that occur due to cosmic radiations in SRAM cells of an FPGA. The system can finally resist all single SEUs that happen in flip flops and all 4 random errors that take place in each register of the register file. All the flip flops and latches are protected using a TMR scheme. The information redundancy in the regiester file to overcome all 4 random errors is 168% and the errors are corrected by means of a mechanesim that is masked from the processor core. In cache memory, each 32 bit data is...

Design of a Fault Tolerant ARM-Based Processor on FPGA

, M.Sc. Thesis Sharif University of Technology Esmaeeli, Siamak (Author) ; Rashidian, Bijan (Supervisor) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

The charged particles in space strike the silicon surface of an embedded system in a satellite and cause fault occurrence in its operation. So some methods should be employed to reduce the effects of the faults. The methods that are implemented in system level are widely used because of their low cost and high reliability. The processors are responsible for performing main processes in embedded systems. On the other hand, the ARM processors are good choices for utilizing in satellites because of their low size, low power consumption and high performance. Also, FPGAs have made a major improvement in embedded system design. So with implementing ...

Resorcinol-formaldehyde xerogel as a micro-solid-phase extraction sorbent for the determination of herbicides in aquatic environmental samples

, Article Journal of Separation Science ; Volume 38, Issue 13 , 2015 , Pages 2305-2311 ; 16159306 (ISSN) Es Haghi, A ; Zare, M ; Piri Moghadam, H ; Bagheri, H ; Sharif University of Technology

2015

Abstract

In this study, organic aerogels were synthesized by the sol-gel polycondensation of mixed cresol with formaldehyde in a slightly basic aqueous solution. Carbon aerogels and xerogels are generated by pyrolysis of organic aerogels. The novel sol-gel-based micro-solid-phase extraction sorbent, resorcinol-formaldehyde xerogel, was employed for preconcentration of some selected herbicides. Three herbicides of the aryloxyphenoxypropionate group, clodinafop-propargyl, haloxyfop-etotyl, and fenoxaprop-P-ethyl, were extracted from aqueous samples by micro-solid-phase extraction and subsequently determined by gas chromatography with mass spectrometry. The effect of different parameters influencing the...

A combined micro-solid phase-single drop microextraction approach for trace enrichment of volatile organic compounds

, Article Analytical Methods ; Volume 7, Issue 16 , Jun , 2015 , Pages 6514-6519 ; 17599660 (ISSN) Bagheri, H ; Zare, M ; Piri Moghadam, H ; Es haghi, A ; Sharif University of Technology

Royal Society of Chemistry 2015

Abstract

An attempt was made to combine μ-solid phase extraction and headspace single drop microextraction techniques and use their advantages for trace determination of some volatile organic compounds in aqueous samples. After performing the two-step preconcentration approach, the desired analytes were determined by gas chromatography-mass spectrometry. A resorcinol-formaldehyde-based xerogel was used as the extraction medium in the μ-solid phase extraction (μ-SPE) method. Then, the extracted BTEX was eluted with a rather large amount of methanol. To remove the laborious process including solvent evaporation and further reconstitution, which is usually accompanied by loss of analytes and accuracy,...

Low Grade Heat Driven Multi-Effect Distillation and Desalination

, Book Rahimi, Bijan ; Chua, Hui Tong

Elsevier 2017

Abstract

Low Grade Heat Driven Multi-effect Distillation and Desalination describes the development of advanced multi-effect evaporation technologies that are driven by low grade sensible heat, including process waste heat in refineries, heat rejection from diesel generators or microturbines, and solar and geothermal energy. The technologies discussed can be applied to desalination in remote areas, purifying produced water in oil-and-gas industries, and to re-concentrate process liquor in refineries.
This book is ideal for researchers, engineering scientists, graduate students, and industrial practitioners working in the desalination, petrochemical, and mineral refining sectors, helping them...

Numerical Investigation of Two-Phase Flow Contains Water and Oil in Hydrocyclones

, M.Sc. Thesis Sharif University of Technology Asadi, Mohammad (Author) ; Farhanieh, Bijan (Supervisor)

Abstract

Having an efficient and reliable system for oil-water separation is of crucial importance in oil and gas industry. Hydrocyclones have been used for more than a century to separate oil from water as well as sand from liquid or gas. The main objectives of this research are as follows: Determination the hydrocyclone principle of operation, based on computational fluid dynamic simulations. Hydrocyclones, in a spite of simple structure, are widely used in industry such as Petrochemical, Mining, Chemical Industries, Pharmacy, Food and Pulp Industries. The CALC BFC is one phase flow numerical code based on finite volume method and SIMPLEC algorithm. It was extended for simulating the two phase flow...

Deposition and Analysis of Indium-Tin-Oxide NanoStructures Using Sputtering

, M.Sc. Thesis Sharif University of Technology Bagheri, Behrang (Author) ; Rashidian, Bijan (Supervisor)

Abstract

Transparent conductive materials have been widely used in semiconductor technology. Among them all, Indium tin oxide (ITO) has been utilized as electrodes in liquid crystal displays, solar cells, heat reflecting films and gas sensors.In general, the desired properties of transparent conductive oxides are high conductance and transmission. However, due to the complexity of ITO molecular structure, the film properties strongly depend on the depositon parameters.In first part of this thesis, physical properties and electrical characteristic of ITO films, different deposition techniques, and effects of deposition parameters (substrate temperature, pressure, power, etc. ) on film properties are...

Fabrication of Metallic Nano-Tip Field Emitters and Measurement

, M.Sc. Thesis Sharif University of Technology Yazdanfar, Payam (Author) ; Rashidian, Bijan (Supervisor)

Abstract

The need for integration of electron guns together with thermal considerations of thermionic cathodes has led to design new cold cathode guns based on field emission phenomenon. In first part of this thesis, basic field emission theories, fabrication methods of field emitter arrays, effect of different parameters on the field emission properties of field emitter arrays and applications of these arrays are investigated. After setting up fabrication methods of nano-tip field emitters, in the second part of thesis, Si nano-tips and Si field emitter arrays are fabricated using of thermal oxidation of silicon substrate, lithography, and chemical etching of silicon oxide and silicon substrate. Si...

, M.Sc. Thesis Sharif University of Technology Salari, Sina (Author) ; Farhanieh, Bijan (Supervisor)

Abstract

Centrifugal Fans are widely used in industrial and commercial applications, from shop ventilation to material handling to boiler applications. They consume extremely high amount of energy each year. Because of this high consumption, even a small efficiency improvement could led to high amount of energy saving. Many projects have been done with this goal up to now, and present work is one of them, with aim to optimize a industrial centrifugal BI fan performance, with wheel diameter about 400 mm. The research has been done based on 3D numerical methods, done by commercial code Fluent 6.3, in steady state. MRF and k-E models have been used to simulate flow around blades, and turbulence...