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shamsaei--abolfazl
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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...
, M.Sc. Thesis Sharif University of Technology ; Shamsaei, Abolfazl (Supervisor)
Abstract
Entrance of air to close water conduits occurs in many ways. This phenomenon makes displeasing effects on water transport structures. Two-phase flows in closed conduits are studied experimentally, numerically and theoretically. Even after decades, due to the complexity of the subject, these studies still require development and reformation. Numerical and theoretical two-phase models are often limited to a special regime of flow."Volume Of Fluid"(VOF) is a model for non-mixing two-phase flows. "Fluent" software uses this model in this field of flows. Volume of fluid is used successfully in some problems like dam break or rising bubbles. Main disadvantage of this model is distribution of the...
Assessment of waterlogging and provide risk maps by using RS, GIS and field data (case study: Qazvin plain)
,
M.Sc. Thesis
Sharif University of Technology
;
Shamsaei, Abolfazl
(Supervisor)
Abstract
Groundwater quality protection has a significant importance due to abundant applications of these resources in various fields such as agriculture, industry and drinking water. Removal of groundwater pollution is a time and money consuming process and often pollution is detected when improving the quality of groundwater is nearly impossible. For this vulnerability assessment there are three methods: Processing, Overlap-Index and Statistical Methods. Overlap-Index is composed of variety of maps such as Geology, Soil, Groundwater Depth and etc which uses in determining of vulnerability Index. In the present study for underground pollution potential determining, four indexes such as AVI، GOD،...
Comparison of River Daily Runoff Simulation Results using Time Series and IHACRES Rainfall-runoff Model
, M.Sc. Thesis Sharif University of Technology ; Shamsaei, Abolfazl (Supervisor)
Abstract
Hydrologic models are the best tools to reduce hydrological uncertainties in rivers runoff estimation. Considering structure of model and calibration of parameters, there are several approaches to extend. In this study, we try to simulate daily river runoff by using two different approaches and then compare the results of them with each other. In first approach, IHACRES model is used to simulate rainfall- runoff, which is a conceptual model based on rainfall, runoff and evapotranspiration or temperature data. This model uses conceptual part to estimate effective rainfall and also it uses a transformation function to transform effective rainfall to output flow. This model works in daily time...
Movement of Entrapped Air-Pockets in the Bottom Outlet of Dams and Solutions to Related Problems
, M.Sc. Thesis Sharif University of Technology ; Shamsaei, Abolfazl (Supervisor) ; Ghaemian, Mohsen (Supervisor)
Abstract
The purpose of this study is to investigate the entrapment and movement of air pockets in the bottom outlet of dams and numerical simulation of the process of entrapment and entrainment of air pockets. One of the most common problems with bottom outlets is the air-water mixture flow. The main purpose of this study is to investigate the causes of air pockets in pressurized tunnels before service and emergency gates in the bottom outlets and to provide effective solutions to prevent the occurrence of unwanted air entrapment and many problems resulting from it. To do this, using FLOW-3D flow simulator, the way of entraping air pockets in the Bottom outlet of Darian Dam has been investigated and...
Experimental Investigation of Mobility and Reactivity of Iron Nanoparticles in Porous Media and Application for in-Situ Groundwater Remediation
, Ph.D. Dissertation Sharif University of Technology ; Shamsaei, Abolfazl (Supervisor) ; Vosoughi, Manoochehr (Supervisor)
Abstract
In the present study, synthesis, preparation, and application of bimetallic iron/nickel nano-particles were experimentally investigated with the aim of groundwater remediation. Firstly, iron/nickel nano-particles were synthesized according to chemical reduction and stabilization with starch biopolymer, and then characterized. Results confirmed the formation of bimetallic iron/nickel nano-particles with mean size of 75 nm that starch placed around of them. The more stability characteristic and also enough mobility ensure their diffusion through porous media. Secondly, reactivity of synthesized nano-particles for removal of various contaminants including nitrate, chromium, and lead were...
Behavior study of high impact resistant reinforced concrete frames using crack conduction method
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Razavi, S. M ; Shamsaei, N ; Sharif University of Technology
American Society of Mechanical Engineers
2006
Abstract
In this study, the influence of crack conduction method on behavior of reinforced concrete (RC) frame under iterative high impact loading were experimented. To investigate the structural behavior through large deformations and progressive damage and to identify the failure modes, the falling weight and falling height were set more than the structural strength in elastic state. A comprehensive scheme which indicated influence of location of initial cracks on behavior and failure mode of structure was developed. Falling weight impact test was conducted on twenty-one laboratory scaled RC frames which were categorized in four series regard to considered scheme. Concrete volume and compressive...
Effective Connectivity Between Nervous System and Cardiovascular System by Time Series Extracted from ECG signal and Frequency Bands of EEG signal
, M.Sc. Thesis Sharif University of Technology ; Shamsollahi, Mohammd Bagher (Supervisor)
Abstract
There is an effective and functional connectivity between the central nervous system and the cardiovascular system, which is controlled by the autonomic nervous system. Investigating this connectivity and its direction can provide valuable insights into their functioning. To examine causal and directional relationships, EEG and ECG signals, which contain useful information about the activities of these two systems, are utilized. Granger causality is a popular method for estimating effective linear connectivity. However, the assumption of linearity in effective connectivity is not always valid, as nonlinear interactions also exist between the nervous and cardiovascular systems. Estimating...
Engineering development of an instrument panel concept using a unified FE modeling approach
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Darijani, H ; Shamsaei, N ; Naghdabadi, R ; Sharif University of Technology
2006
Abstract
In today's global economy, the automotive design engineer's responsibilities are made more complex by the differences between regulatory requirements of the various global markets. This paper compares instrument panel head impact requirements of FMVSS 201 with its European counterparts, ECE 21. The behavior during a head impact test has been studied. Due to the gravity of the cockpit module, the sag has been analyzed to simulate shipping, loading, and assembly conditions. The interior parts of the vehicle cabin are exposed to temperature variations due to radiation effect of sun ray or freezing temperature in winter. Plastic parts appear to be more thermally susceptible than steel parts in...
Stress analysis of three-unit all-ceramic dental bridges using FEM
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Farahmand, F ; Shamsaei, N ; Eslami, G. R ; Sharif University of Technology
2006
Abstract
Mechanical fracture is a common cause of failure for 3-unit dental bridges, particularly, the all-ceramic structures. The purpose of the present study was to evaluate the effect of convergence angles of the abutments on the distribution of the mechanical stresses, within the prosthesis and at the restoration-abutments interface of a 3-unit all-ceramic bridge. The 3-D geometrical data of the second premolar and first and second molar teeth were obtained using ATOS scanner system and utilized for reconstruction of a surface model of the 3-unit bridge in I-Deas as solid modeler software. This was then transferred to MSC/Nastran software for mesh generation and finite element analysis. Two FE...
Numerical Study of Geotextile Application in Downstream Filter Zone of an Embankment Dam with Clay Core
, M.Sc. Thesis Sharif University of Technology ; Shamsaie, Abolfazl (Supervisor)
Abstract
Nowadays, applications of the synthetic materials are developing in civil engineering projects and widely used in these projects. Therefore, during previous years; use of the Geotextiles as one of the Geosynthetic materials in order to filtration, drainage, separation, soil protection, etc have developed ever-increasing. The goal of this research is modeling and studies of the Geotextiles application in the downstream filter zone of embankment dams in combination with granular materials using FLAC2D software. Gordeh Bin embankment dam situated in West Azerbaijan province has been chosen as case study. In this matter, different models have been made with changes in thickness of the inclined...
Efficient Management of River Water Quality Based on Pollution Trading Approach
, Ph.D. Dissertation Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
“Sustainable development” is a frequently used phrase, but the idiom has been experienced little since it was coined by the Brundtland, due to its intrinsic complications. The issue is going to compromise two key components; economy and ecology. One of the solutions based on concept of sustainable development that has been proposed for maintaining water quality at acceptable levels is to cap pollutant emissions at a sustainable level, then establish an economic market in which the right to discharge pollutants is traded according to market supply and demand mechanisms. Water quality trading or pollution trading is one such kind of market-based program that has also been described using names...
Semi-supervised Breast Cancer Subtype Clustering Using Microarray Datasets
, M.Sc. Thesis Sharif University of Technology ; Motahhari, Abolfazl (Supervisor)
Abstract
Gene expression microarrays can be used for precision medicine and targeted therapies. The data generated by microarrays are high-dimensional causing statistical inference of any parameter a daunting task. In this thesis, it is shown that regardless of high-dimensional datasets produced by microarrays, the inference can be robust in the sense that random selection of features results in the same conclusion as far as the number of selected features are chosen appropriately. Stratifying patients with breast cancer based on their gene expression levels shows that patient subtypes are almost independent of the feature selection strategy. Moreover, using less noisy datasets coming from RNAseq...
A Simulation for Better Understanding of Integrin Clustering and Activation
, M.Sc. Thesis Sharif University of Technology ; Motahhari, Abolfazl (Supervisor)
Abstract
Today, computer simulations are employed prevalently by researchers to understand biological processes. The tendency to use computational methods has been increased recently due to the high costs and errors of experimental methods. Integrins are membrane proteins that mechanically attach cells to the extra cellular matrix (ECM) and derive some behaviors such as cell migration. Moreover, integrins have biochemical functions. They transduce environment signals and trigger chemical pathways. As a result, integrins regulate cell shape, motility, etc. The investigation of integrin behavior in a real environment is very difficult due to the presence of many other proteins that interfere with the...
Hydro-economical Method for the Optimal Capacity Design of Small Hydropower Plant (Case Study: Kohneh Lahijan Hydropower Plant)
, M.Sc. Thesis Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
In this thesis, we determine the optimal capacity of the power plants considering site specifications and Flow Duration Curve and evaluating economic parameters. Finally a design with more sufficient economical and hydrualical performance would be selected. The optimization algorithm used in this thesis is called "Charged System search" that is one of the newest meta-heuristic algorithms. This algorithm is inspired by the coulomb and gauss's laws of electrostatics in physics and utilizes a number of charged particles which influence each other based on their fitness values and their separation distances considering the governing law of coulomb.The proposed method in this thesis can be...
GIS Based Procedure to Determine Location of Cascade Small Hydropower Plants Case Study, Nokhan Area
, M.Sc. Thesis Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
Coinciding with the worldwide environmental issues and increasing demand for clean energy sources, hydropower plants have highly attracted decision- makers attention. Low manufacturing costs and pollutions which are made by these plants in comparison with another types of powerhouses, could be reason of that. And so on, hydropower locating and evaluating studies have been highly increased recently, specifically in developing countries. From the point of operation procedure, hydropower plants are generally divided in two types, run-of-he-river and storage projects. This study has concentrated on run-of-he-river projects and due to spotting plant location, Sefidbarg river basin...
Investigation of bed Stability in Downstream for the Diversion dam under Scour (Mill & Moghan case study)
, M.Sc. Thesis Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
Numerical simulations and large eddy simulations (LES) of turbulent flow downstream of diversion dam , pool-riffle bedform in different geometrical ratios (different lengths of riffle and pool) with flow Reynolds number of 3.0 E+04 to 3.3E+04, downstream of special case study "Mill and Moghan diversion dam" with Froude number of 0.5 are presented The calculations are performed using a computational fluid dynamics model, FLOW-3D, which solves the Navier-Stokes equations in three dimensions with finite volume method. Numerical simulations are validated by comparing the numerical results of time-averaged flow patterns downstream of pool-riffle sequence with that of the experimental...
Assessment of Optimum Environmental Flows Using Economic Evaluation Methods
, M.Sc. Thesis Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
One of the main challenges of Water Resources Planning and Management (WRPM) is to balance water allocation between different uses. Usually, due to political and economic power of other uses, ecosystem receives less attention. Environmental flow is the allocated flow to ecosystem. Ecosystem provides a wide range of services to humanity. Therefore, environmental flow is not exclusively a matter of sustaining ecosystem but also a matter of providing humans with better life. Several methods have been developed to determine the environmental flow but only a few consider its socio-economic aspects. Consideration of these aspects could assist decision-makers with determining the optimum flow and...
Application of Gis & Fuzzy Technique for Order-Preference by Similarity to Ideal Solution (Topsis) in Siting Water Reservoires
, M.Sc. Thesis Sharif University of Technology ; Shamsai, Abolfazl (Supervisor)
Abstract
Sustainable agricultural development in the country without regard to water supply problems in terms of time and place is not possible. Construction of water storage tanks filled with water and seasonal use in dry seasons in the effective action in the optimal use of water in the climate of (low and irregular rainfall) is. The most important step in the construction of water storage tanks to choose the best point for the construction of the reservoir basin in order to reduce costs and increase efficiency. Chndmyarh different methods to decide the best option for finding a few options from there. Among these methods can be Tapsys two methods (TOPSIS) and hierarchical analysis (AHP) pointed...
Analysis of Genes Regulating Beta Cells Cell Cycle
, M.Sc. Thesis Sharif University of Technology ; Motahari, Abolfazl (Supervisor)
Abstract
Diabetes mellitus is a group of disorders where the level of blood sugar remains high for a long period of time. This increase may be due to either reduced insulin secretion from the pancreatic gland, or insulin resistance, or both. Another key reason is the destruction of beta cells due to functional defect in the body’s immune system. Current treatments include controlling diet, insulin injection and pancreatic transplantation, all of which are temporary. For this reason, finding genetic factors participating in the progression of the disease and adapting treatments to these factors are under intensive studies.In this thesis, available information resources including genomic, biological...