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    The effect of soil-structure interaction on damage index of buildings

    , Article Engineering Structures ; Volume 30, Issue 6 , 2008 , Pages 1491-1499 ; 01410296 (ISSN) Nakhaei, M ; Ali Ghannad, M ; Sharif University of Technology
    2008
    Abstract
    The effect of Soil-Structure Interaction (SSI) on Park and Ang Damage Index in a Bilinear-SDOF model is investigated under seismic loading. This is done through an extensive parametric study. Two non-dimensional parameters are used as the key parameters which control the severity of SSI: (1) a non-dimensional frequency as the structure-to-soil stiffness ratio index and (2) the aspect ratio of the structure. The soil beneath the structure is considered as a homogeneous elastic half space and is modeled using the concept of Cone Models. The system is then subjected to three different earthquake ground motions as the representative motions recorded on different soil conditions. The analysis is... 

    The effect of soil-structure interaction on hysteretic energy demand of buildings

    , Article Structural Engineering and Mechanics ; Volume 24, Issue 5 , 2006 , Pages 641-645 ; 12254568 (ISSN) Nakhaei, M ; Ghannad, M. A ; Sharif University of Technology
    Techno-Press  2006
    Abstract
    The effect of soil-structure interaction (SSI) on hysteresis energy demand of buildings using an ensemble of alluvium site records was investigated. The structure and the soil were molded separately and then combined to constitute the soil-structure model using the sub-structure method. The key parameters effecting the response of the soil-structure system were found to be a non-dimensional frequency as a representative of structure to soil stiffness ratio; and aspect ratio of the building. It was found that the hysteric energy dissipated in a structure under an earthquake can be highly effected when the stiffness of the soil beneath the structure is altered  

    Mechanical Design and Fabrication of a Parallel Hybrid Vehicle Powertrain Simulator

    , M.Sc. Thesis Sharif University of Technology Nakhaei, Hamid (Author) ; Saadat Foumani, Mahmoud (Supervisor)
    Abstract
    In this research, the mechanical section of a reduced-scale hybrid vehicle simulator was designed and fabricated. In order to scale down the vehicle dynamics, a method based on dimensional analysis was proposed. An internal combustion engine and an electric motor were selected as power sources and then, scaling was performed, according to the specifications of the combustion engine. Afterwards, the power transmission system was designed first in concept and then in more detail. Finally, the design was manufactured and assembled. The study was made in conjunction with another study responsible for the controlling section of the work, conducted by Safabakhsh The sponsor of these two researches... 

    A Reinforcement Learning Approach for Dynamic Pricing (Case Study: Iran Electrical Power Grid)

    , M.Sc. Thesis Sharif University of Technology Nakhaei, Hamid (Author) ; Shadrokh Sikari, Shahram (Supervisor)
    Abstract
    Population growth and the escalating use of electric devices have led to a surge in electricity demand. However, the construction of adequate infrastructure to meet this additional demand is highly expensive. To address this issue that sometimes causes power outages, dynamic pricing for electricity, a demand management technique, has gained significant importance. By employing this method, prices can be adjusted on an hourly basis, enabling consumers to regulate their consumption in response to these price fluctuations. The prices can be determined based on different objective functions. This research aims to develop a comprehensive framework for determining the optimal hourly electricity... 

    Super Hydrophobic Ni Coating on Steel by Electrodeposition Method

    , M.Sc. Thesis Sharif University of Technology Nakhaei Niya, Hamzeh (Author) ; Dolati, Abolghasem (Supervisor)
    Abstract
    In this study, the properties of super-hydrophobic Ni coating on carbon steel including wetting behavior and corrosion resistance of Nickel coatings deposited on the steel substrate were investigated. For this purpose, Nickel coatings deposited by electrodeposition method in deferent current density (10,20,30,50, 70 mA /cm2) in bath containing 1.5 mol of ethylene de-ammonium de-chloride, 0.5 mol H3BO3, 1 mol Nicl2.6H2o and then immersed in a bath containing 0.01 mol per liter myristic acid and ethanol for 24 hours and then placed in the room temperature for 14 days. Deferent tests were used for characterization, wettability properties, corrosion behavior and morphology of Ni coatings. The... 

    Rutting and moisture resistance evaluation of polyethylene wax–modified asphalt mixtures

    , Article Petroleum Science and Technology ; Volume 34, Issue 17-18 , 2016 , Pages 1568-1573 ; 10916466 (ISSN) Nakhaei, M ; Darbandi Olia, A. D ; Akbari Nasrekani, A ; Asadi, P ; Sharif University of Technology
    Taylor and Francis Inc  2016
    Abstract
    One of the methods newly introduced in pavement technology to address environmental concerns and reduce total gas emission is warm mix asphalt (WMA) technology. In this study, polyethylene wax is used to produce WMA mixtures. Although this technology has several positive features, moisture and rutting resistance of WMA mixtures are always questionable. To evaluate moisture and rutting resistance of polyethylene-modified mixtures, indirect tensile strength and dynamic creep tests were used, respectively. Results indicated that polyethylene has positive effect at low compaction temperature on moisture resistance, and also has negative effect on rutting resistance  

    Effectiveness Evaluation of Making Natural Childbirth Free of Charge on Household Decision in Choosing Delivery Method

    , M.Sc. Thesis Sharif University of Technology Ashtari Nakhaei, Aida (Author) ; Fatemi Ardestani, Farshad (Supervisor) ; Heidarzadeh, Mohammad (Co-Advisor)
    Abstract
    The rate of cesarean section delivery in Iran is high and during the past 14 years, leading up to 2014, kept rising. In this regard, decreasing cesarean section rate was targeted through the healthcare reform plan, which was offered by Ministry of Health and Medical Education. This plan kicked off on May4, 2014. One of the most important proceedings of this plan was making natural childbirth to be free in all hospitals, which are under the auspices of the medical universities. According to healthcare utilization models, lower prices of healthcare services, more health centers and more accessibility to them, increase the probability of using health care services. Current study evaluated the... 

    Path Simplification Game

    , M.Sc. Thesis Sharif University of Technology Nakhaei Pour Rokerd, Mohammad Hossein (Author) ; Abam, Mohammad Ali (Supervisor)
    Abstract
    The problem of path simplification is an important problem in computer science. With the advances in navigation and geographical information based systems, simplification and data compression have gained considerable importance. The intends to find a path with less weight than the provided path while estimating the initial path with good accuracy and simplifying the storage and process cost of path information. This problem is not only useful in Geographical Information Systems, but it also has use cases in image processing and computer graphics and has been studied a lot in computational geometry. In this research, we introduce a simplification game that models the limited version of the... 

    Optimizing Transmisson from Distant Wind Farms

    , M.Sc. Thesis Sharif University of Technology Abdollahi Mansourkhani, Hamid Reza (Author) ; Hosseini, Hamid (Supervisor)
    Abstract
    Wind power is site dependent and is by nature partially dispatchable. Furthermore, good wind sites are far from grid. Due to these problems, and along with the existing limitations in the transmission networks, a comprehensive analysis over an extended time is needed to properly explore all potential wind sites for wind capacity allocation. This problem is computationally expensive and decomposition methods are required to break down this problem. Here Benders decomposition approach is used, which is a popular technique for solving large-scale problems, to decompose the original problem into a master and a subproblem. The master problem is a linear problem, which allocates wind capacity to... 

    Identification of the Set of Single Nucleotide Variants in Genome Responsible for the Differentiation of Expression of Genes

    , M.Sc. Thesis Sharif University of Technology Khatami, Mahshid (Author) ; Rabiee, Hamid Reza (Supervisor) ; Beigi, Hamid (Supervisor)
    Abstract
    Single nucleotide polymorphs, There are changes caused by a mutation in a nucleotide in the Dena sequence. Mononucleotide polymorphisms are the most common type of genetic variation. Some of these changes have little or no effect on cells, while others cause significant changes in the expression of cell genes that can lead to disease or resistance to certain diseases. Because of the importance of these changes and their effect on cell function, the relationships between these changes are also important. Over the past decade, thousands of single disease-related mononucleotide polymorphisms have been identified in genome-related studies. Studies in this field have shown that the expression of... 

    Synthesis & Characterization of Au-HKUST-1 Nanocomposite and Evaluation of Plasmonic Properties of Gold Nanoparticles in this Nanocomposite

    , M.Sc. Thesis Sharif University of Technology Moazzeni, Hamid Reza (Author) ; Madaah Hosseini, Hamid Reza (Supervisor)
    Abstract
    In the past few years, many research works on the controllable integration of metal nanoparticles and metal-organic frameworks were done, since the obtained composite material shows a synergism effect in catalysis and photocatalysis, drug delivery applications, gas, and energy storage, as well as sensing. For the first time, in this study, we employed template-assisted growth to synthesize Au-HKUST-1 Nanocomposite. XRD analysis entirely confirms that employing this strategy in synthesizing Au-HKUST-1 was wholly successful, and the plasmonic properties of this nanostructure were studied via UV-visible spectroscopy. In the course of synthesis, gold nanoparticles with 70nm diameter were... 

    Detection of Central Nodes in Social Networks

    , Ph.D. Dissertation Sharif University of Technology Mahyar, Hamid Reza (Author) ; Movaghar, Ali (Supervisor) ; Rabiee, Hamid Reza (Supervisor)
    Abstract
    In analyzing the structural organization of many real-world networks, identifying important nodes has been a fundamental problem. The network centrality concept deals with the assessment of the relative importance of network nodes based on specific criteria. Central nodes can play significant roles on the spread of influence and idea in social networks, the user activity in mobile phone networks, the contagion process in biological networks, and the bottlenecks in communication networks. High computational cost and the requirement of full knowledge about the network topology are the most significant obstacles for applying the general concept of network centrality to large real-world social... 

    Synthesis of Magnetite (Fe3O4)-Avastin Nanocomposite as a Potential Drug for AMD Treatment

    , M.Sc. Thesis Sharif University of Technology Zargarzadeh, Mehrzad (Author) ; Maddah Hosseini, Hamid Reza (Supervisor) ; Delavary, Hamid (Co-Advisor)
    Abstract
    Age-related macular degeneration (AMD) is the most common cause of vision loss in those aged over 50. There are two main types of AMD, Wet and Dry form. Wet AMD is more severe though more treatable. There are three conventional treatments for AMD including laser therapy, surgery and intravitreal injection of anti-VEGF into the eye. Delivery of drugs to the posterior segment of the eye is still challenging and several implants and devices are currently under investigation for their ability to stimulate the retina, producing visual percepts. The application of intravitreal bevacizumab (Avastin) has expanded tremendously from the time of its introduction into ophthalmic care since 3 years ago.... 

    Analysis of Gene Expression Data in Bioinformatics Data Sets Using Machine Learning Approaches

    , M.Sc. Thesis Sharif University of Technology Bagherian, Misagh (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    As a robust and accurate classification of tumors is necessary for successful treatment of cancer, classification of DNA microarray data has been widely used in successful diagnosis of cancers and some other biological diseases. But the main challenge in classification of microarray data is the extreme asymmetry between the dimensionality of features (usually thousands or even tens of thousands of genes) and that of tissues (few hundreds of samples). Because of such curse of dimensionality, a class prediction model could be very successful in classifying one type of dataset but may fail to perform well in some other ones. Overfitting is another problem that prevents conventional learning... 

    Comparision of Single Service Call Admission Control Schemes in Cellular Mobile Networks

    , M.Sc. Thesis Sharif University of Technology Firouzi, Zahra (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    In single service wireless cellular networks, two types of call are defined; new call and handoff call. New call blocking probability and handoff call dropping probability are two major parameters of QoS. Some call admission control schemes are proposed for handling new and handoff calls in the cell for keeping these QoS parameters under suitable values. In this work, we will introduce some call admission control schemes and will show performance analysis, advantages and disadvantages of them (under different channel holding times and same channel holding times for new calls and handoff calls). Then we will focus on two schemes and based on their ideas, we will propose a new call admission... 

    Cost-Sensitive Classifiers and Their Applications

    , M.Sc. Thesis Sharif University of Technology Ahmadi, Zahra (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Decision making often has different effects and results with unequal importance. Most of classifiers try to minimize the rate of misclassified instances. These classifiers assume equal costs for different misclassification types. However, this assumption is not true in many real world problems and different misclassification types have different costs. These differences can be applied by introducing the cost in the process of learning. In this manner, total cost of misclassification will be the evaluation metric of classification. In order to apply this metric to the problems, new learning algorithms are needed. Cost-sensitive learning is the related area of machine learning which deals with... 

    Analyzing the Energy Consumption of Error Control Mechanisms in Wireless Sensor Networks

    , M.Sc. Thesis Sharif University of Technology Khodadoustan, Safieh (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Nowadays wireless technology is widespread all over the world, because of extensive and successful application of low cost, low power, multifunctional tiny sensor nodes that can be grouped to make up of a wireless sensor network (WSN). Some of Wireless sensor network technologies include Zigbee, EnOcean, Personal area network, Ultra-Wideband and Bluetooth which this thesis focuses on the last one. Scalability, mobility, reliability and energy efficiency are some of the requirements and challenges of WSNs, which among them reliability and reducing energy consumption are two important objectives in wireless sensor networks. Since each sensor node has limited energy to consume, overcoming the... 

    A Study on Credit Assignment among Reinforcement Learning Agents

    , M.Sc. Thesis Sharif University of Technology Rahaie, Zahra (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Nowadays, multi-agent systems as part of the distributed artificial intelligence play an important role in modeling and solving complex industrial and commercial problems. They have distinguishing characteristics such as distributiveness (spatial, temporal, semantic, or functional distribution), robustness, parallel processing, etc. One of the capabilities that can be added to this system is the learning capability. It can help the system to adapt itself to the new environment. This paper proposed a method for the problem of credit assignment in multi-agent domain. Solving the multi-agent credit assignment problem, one can expect individual learning for a single agent in systems of... 

    Cellular Learning Automata and Its Applications in Pattern Recognition

    , M.Sc. Thesis Sharif University of Technology Ahangaran, Meysam (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Cellular learning automata (CLA) is a distributed computational model that is introduced recently. This model is combination of cellular automata (CA) and learning automata (LA) and is used in many applications such as image processing, channel assignment in cellular networks, VLSI placement, rumor diffusion and modeling of commerce networks, and obtained acceptable results in these applications. This model consists of computational units called cells and each cell has one or more learning automata. In each stage, each automaton chooses an action from its actions set and applies it to the environment. Each cell has some neighboring cells that constitute its local environment. The local rule... 

    An Uplink Packet Scheduling Algorithm in Fixed PMP WiMAX Networks with TDD Frame Structure

    , M.Sc. Thesis Sharif University of Technology Nazari, Sonia (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Worldwide interoperability for Microwave Access (WiMAX) is one of the most dominant cell-based broadband wireless metropolitan access technologies. Packet scheduling algorithm specifies the packet transmission order. In WiMAX standard, packet scheduling algorithm is not defined and its efficient design is left for developers and researchers. The existing researches in the scope of uplink packet scheduling, which is the most challenging packet scheduling scheme, consider only one cell. However the uplink available resources might not be enough when there are many packets that should be scheduled. To solve this problem, we propose an algorithm that uses the load balancing mechanisms that are...