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agha-mohammad-ghasem--maryam
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Multi Level and Multi Products Location-routing Problem for Perishable Foods under Uncertainties
, M.Sc. Thesis Sharif University of Technology ; Rafee, Majid (Supervisor)
Abstract
Distribution is a necessary part of a supply chain. Location-routing problem is a problem that decide about location of facility , allocation and routing for vehicle. This research focus on modeling for multi-level and multi-product for perishable foods that include five suppliers, three plants, two depots and ten costumers. costumers and products classify according to their importance for the company and their quality into three batch. In order to decreasing of cost return orders and damaged products, a special system are Designed that products can be sent again. In real world we do not have any certain data for model’ parameters, then we consider uncertainty and use robust for showing...
Incomplete Reduction of Iron Ore in a Fluidized Bed Reactor
, M.Sc. Thesis Sharif University of Technology ; Halali, Mohammad (Supervisor)
Abstract
The main goal of current investigation was partial reduction of Fe2O3 available in Hematite-rich ore to Magnetite by Fludization Bed method. The reductive gas, CO, was produced by incomplete combustion of Acetylene and Airmixed in inappropriate ratio. X-Ray Diffraction and X-Ray Florescence analyses were implemented in order to conducting qualitative analysis of present phases before and after reduction of the ore. Quantitative analysis of the same phases was also conducted by Titration. The latter analysis revealed the precise magnitude of available iron in each of the oxide containing phases. The chemical composition of the reactor gas was also determined before and after reduction...
Leakage Cancellation from Transmitter to Receiver
, M.Sc. Thesis Sharif University of Technology ; Atarodi, Mojtaba (Supervisor) ; Safarian, Amin Ghasem (Supervisor)
Abstract
The wideband code-division multiple access (WCDMA) system has been widely used for the third-generation wireless communication system. It uses Frequency division duplexing for two-way communication by a transceiver. Although a duplexer will significantly suppress the TX leakage signal (50dB-60dB), a residual attenuated signal still remains at the receiver input and act as a strong blocker which reduces the sensitivity of the receiver. For reducing the effect of the TX leakage on the RX performance, a band pass RF SAW filter is typically inserted between the LNA and the mixer to reject the TX leakage. However, this filter increases the system cost and size. This encouraged us to propose a novel...
Design Principles of Permeable Pavement in Pollutants Removal from Surface Runoff
,
M.Sc. Thesis
Sharif University of Technology
;
Tajrishi, Agha Mohammad Hossein
(Supervisor)
Abstract
Urbanization increases impervious surfaces and therefore reduces land permeability. As a result, higher amount of runoff is produced which leads to environmental degradation and economic loss. Use of pervious/permeable pavements is an efficient approach to reduce runoff volume and improve the quality. In this study, different design methods of pervious/permeable surface are first described using structural and hydrological modules. Then, a software program for pervious/permeable surface design is put forth. Supported by various available design methods (focusing on pervious surfaces in Iran), the software employs structural, hydrological, economic (cost estimation) and qualitative...
Water Allocation Modelling on the Basis of Hydrological Characteristics Critical Plains (Case Study: Mashhad Plain)
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
The Mashhad plain is one of the most important plains in Khorasan-e-Razavi province. In the last decades, rapid population growth coupled with agricultural expansion has tremendously increases pressure on the groundwater resources. Large increases in water demands with little recharge have strained the plain groundwater resources resulting in declines in water level in last decades. Due to declining of groundwater level, digging new wells has been forbidden since 1965. In this thesis, users in agricultural, municipals and industrial sections have been modeled with Multi-Agent System, and results of their water extraction on groundwater level have been modeled with GMS. There are two...
Distributed Design of Structured Optimal Controllers Using Chordal Decomposition
, M.Sc. Thesis Sharif University of Technology ; Babazadeh, Maryam (Supervisor)
Abstract
This thesis addresses the distributed optimal control problem. In order to solve this problem a suboptimal distributed design approach has been developed using tools from graph theory and optimization theory. The first objective of this thesis is overcoming the non-scalability of distributed control problems for larges -scale systems. The second objective is using minimum information of other subsystems in the design layer. First, the problems of designing a structured controller minimizing the H_2 and H_∞ norms of the closed-loop system have been formulized and stated as semidefinite optimization problems. Then in order to use the fundamental results that links the chordal graphs and...
Design of Scaffolds with Multi-scale Engineered Microchannels
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor)
Abstract
Building complex and functional tissues and organs is very challenging. One of the challenges is building an efficient network of blood vessels that can be used to facilitate the transport of nutrients and oxygen to the host. In addition to using channels for oxygen supply, another solution is to use oxygen-carrying materials. In this study, in addition to designing and simulating scaffolds with multi-scale microchannels, calcium peroxide was used to release oxygen and eliminate hypoxia in the scaffold. Here alginate is used as the main material for scaffolding. In an attempt to build a scaffold using a bio-printer, pluronic acid was also used as a sacrificial material to create canals....
Evaluation of Data Mining in Salinity Prediction and Evaporation Estimation
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
Since physical variables are almost dependent, uncertain and have significant time and spatial changes, nature of hydrological and environmental systems is so complicated, nonlinear and dynamic. Many models have been developed for studying and analyzing various phenomena in these systems. Recently data mining approaches have been used as new methods for modeling of complicated engineering systems. In this study, performance of several data mining tools in analyzing two phenomena in water quality management have been evaluated. These algorithms are Multilayer Perceptron Neural Network (MLP), Radial Basis Function Neural Network (RBFN), Support Vector Machines (SVMs) in the field of Artificial...
The Economics of Stormwater BMPs
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
In recent decades, local, regional and national research programs have discovered stormwater runoff as the principal cause of water pollution in most urban areas. To solve urban stormwater runoff problems, we should use revisory measures. This is possible by using Best Management Practices (BMPs). BMPs are innovative technologies to reduce the movement of pollutants from land into surface or groundwaters, in order to protect water quality within natural and economic limitations.Three types of BMPs are discussed in this study; swale, bioretention systems and pond. They have different installation requirements, costs and pollutant removal efficiency. The main objective of this research is to...
Investigation of Dust-Causing Factors in Western Iran and Its Effects on Climate Changes
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
study has been divided into two main sections. In the first section, six climate variables have been analyzed in 15 synoptic stations in Iran’s west region through parametric and non-parametric statistical tests in order to find the climate varibility. The results illustared that, in general, there is no climate variability in the western part of Iran. Investigation of climatic indices and changes in the meteorological data in the entire study area (including a large portion of Middle East), in a 30 year period (1979-2008), is eloquent of a drought during the last 10 years of the period. In the second section, by means of the Aerosoal Index (AI) extracted from TOMS and OMI tools, it was...
A Game Theory Approach to Airline Fleet Desing; a Case of Commercial Formation Flight
, M.Sc. Thesis Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
Increasing aviation share in air pollution, population growth, scarcity of available resources such as land (airport), airspace and energy along with uncertainties in air transportation demand and energy market, has motivated the industry stakeholders to push researches toward sustainable models in fleet planning and design. In this thesis we have investigated the suitability of a decision-making model for airline fleet management, based on “Game Theory” and the idea of commercial formation flight (COFOFS). We intend to examine the circumstances under which, an airline needs to substitute a wide-body aircraft with number of smaller ones, while employing the approach of formation flight....
Modeling the Flow and Infiltration of Surface Runoff in Swales
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
Urbanization and increase in impervious areas owing to building construction, pavements of streets, parking lots and sidewalks, amount of surface runoff in cities has been rose. One of the environmental problems of Tehran during the rainfall is the high polluted runoff flowing in the city and eventually transfers pollution to aquifers. So in order to decline the consequences of this polluted surface runoff, it is crucial to understand how the runoff and pollution form. One way of decreasing pollution in runoff is hiring swales attenuation potential. In this study, problems associated with runoff, particularly in relation to the formation, transformation and removal of pollutants from runoff...
Determining the Ecological Balance of Lake Urmia According to Climatic Fluctuations and New Water Conditions in the Region
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Masoud (Supervisor)
Abstract
Lake Urmia is the largest inland lake of Iran and one of the most important water ecosystems in Iran and the world. The ecosystem of this lake is a typical example of a closed drainage basin into which all the runoff flows in the rivers of the basin are discharged. Because of its unique natural and ecological features, Urmia Lake has been declared as a national park since 1346, along with Kabudan and Qion Daghi islands, among the protected areas. Among the most important invertebrates in the lake, we can mention Artemia, which is a species of saltwater shrimp and one of the native species of Lake Urmia. This species is the most important source of food for many water birds such as flamingos....
Detection of Movement Related Cortical Potentials in EEG
, M.Sc. Thesis Sharif University of Technology ; Shamsollahi, Mohammad Bagher (Supervisor)
Abstract
Movement-Related Cortical Potentials (MRCPs) are a subset of Event Related Potentials (ERPs). The event that MRCPs are related to is the endogenous event of self-paced voluntary movement. Like many other ERPs, MRCPs have small amplitudes relative to the background EEG activity, making it difficult to detect them on a single-trial basis. Nevertheless, detection of MRCPs with good accuracy can be vastly benecial to automated rehabilitation systems and to Brain-Computer Interfaces. In this project, a new experimental protocol for MRCP is introduced and signals recorded using this protocol are analyzed. The protocol has been designed and recordings have been made by the author during the summer...
Groundwater Modelling with the Use of Remote Sensing Technology to Assess the Impact of Changes in Aquifer Conditions on Surface Flow (Case Study: Miandoab plain-Urmia Basin)
, M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
Abstract
Groundwater resources are considered as important resources of fresh water specifically in arid and semi-arid regions like Iran. Urmia Lake (UL) basin is one of these regions where groundwater resources play an important role in supplying water and due to inappropriate water resources management during the last two decades it has faced serious problems, like declination of water level in UL. Groundwater and surface water form an integrated system in the UL basin and have a mutual effect on each other. Hence, any improvement in exploitation of aquifers in that region could benefit UL water demand management. Appropriate water resources management in Miandoab plain which transfer almost 50...
Experimental Study of the Wing Sweep Angle Effect on the Pressure Distribution of a Half Model
, M.Sc. Thesis Sharif University of Technology ; Soltani, Mohammad Reza (Supervisor)
Abstract
In this thesis the behavior of a 3D wing has investigated by Flow visualization and pressure acquisition test. The goal of this tests was considering changes in 3D wing section parameter in comparison with 2D airfoils. The performed Tests showed that variation in 3D wing treatment is affected by finite aspect ratio and sweep angle and also indicate changes in pressure profile, increasing pressure peak and decreasing effective speed. CFD studies has conducted to investigate special effect of sweep angle and show that lift and drag coefficient decrease with increasing sweep angle. Also different section pressure profile near the wing tip and intersection of wing/fuselage varies and miss...
A Multi-Objective Optimization Framework for Human Resource Allocation in Large Organizations: A Goal Programming Approach
, M.Sc. Thesis Sharif University of Technology ; Rezapour, Maryam (Supervisor)
Abstract
In the contemporary era where organizations face increasing competition in the global market, human resources analytics has emerged as a crucial strategic tool. Human resources data analysis enables organizations to make more effective workforce management decisions through a systematic and data-driven approach. The primary challenge addressed in this research is the complexity of optimal human resource allocation across various job positions. This challenge stems from multiple variables involved in the process, including candidate competencies, organizational requirements, and labor market conditions. The high volume of applicants and job positions in today’s labor market has further...
Spacecraft Control for Capturing Space Debris via Machine Learning Methods
, M.Sc. Thesis Sharif University of Technology ; Kiani, Maryam (Supervisor)
Abstract
The primary purpose of the present research is development and implementation of advanced state estimation and control techniques for space rendezvous and docking. To achieve this aim, the present study has first investigated the use of graph neural networks (GNNs) to filter out the noise of the sensor data in the state estimation process. The measurement package is consisted of a gyroscope, star trackers, and a GPS sensor providing inputs to the GNNs. The obtained results showed that the use of GNNs significantly improves the accuracy of the state estimation compared to traditional methods. In addition, the study has focused on developing advanced control techniques for spacecraft position...
Scheduling Aircraft Takeoffs and Landings Considering Taxi Times and Landing Delay Patterns
, M.Sc. Thesis Sharif University of Technology ; Radman, Maryam (Supervisor) ; Reihaneh, Mohammad (Supervisor)
Abstract
Efficient utilization of runways, as major bottlenecks at airports, not only minimizes flight delays but also plays a vital role in reducing fuel emissions and mitigating environmental impacts. Aircraft scheduling problem studied in this paper seeks to improve this efficiency through optimally scheduling departure/arrival aircraft on multiple runways. The primary innovation of this study lies in accounting for aircraft taxi times between runways and gates, as well as the landing delay patterns, which have not been simultaneously addressed in the literature. To solve the problem, an enhanced branch-and-price method has been developed, improving upon existing approaches in the literature. It...
Effect of Lumbar and Soleus Proprioception on Kinematic Variability and Dynamic Stability of the Trunk and Center of Pressure Parameter in Healthy Individuals and Low Back Pain Patients
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohammad (Supervisor) ; Hoviattalab, Maryam (Supervisor)
Abstract
Low Back Pain is one of the most problems in health domain which has a high treatment costs, also has high recurrence rates. Postural stability has been introduced as a health characteristic for musculoskeletal systems. Body stability is maintained with sensory feedback data such as Eyes, Vestibular and proprioception data which are sent to brain. Prior investigations have shown that proprioception data have many disorders in lumbar area of Low Back Pain patient and this data are not sent to brain encounters so many problems for muscle activation and stability of body. Researches have been indicated that Low Back Pain patients rely on Ankle proprioception more than healthy people and less...