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elasticity
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Providing Design Spectrum for Iran Based on the New Generation of Ground Motion Model
, M.Sc. Thesis Sharif University of Technology ; Alijani Moghaddam, Hassan (Supervisor)
Abstract
Due to the inelasticity of the ground and geometric expansion, seismic waves are reduced by moving away from the center of wave propagation, which is called the attenuation of seismic waves. Therefore, the ground motions that occur at the site of the structures are different from the ground motions that are emitted from the source. The upcoming study investigates the attenuation of seismic waves in the geographical area of Iran based on the accelerogram data of Iran. Considering the consecutive occurrence of moderate to large earthquakes in Iran, the development of Iran's accelerography network, and the need to update the attenuation relationships by considering the parameters effective in...
Human Motion Imitation and Learning It by Fuzzy Elastic Matching Machine
, M.Sc. Thesis Sharif University of Technology ; Bagheri Shouraki, Saeed (Supervisor)
Abstract
In this thesis, the goal is movement recording by observer and learning it to Fuzzy Elastic Matching Machine (FEMM). For this purpose, first using the camera (Microsoft LifeCam HD-3000), the information specified on the man, taken during the move. After preprocessing performed on the data, Data on each node of the FEMM the classified and is given to special FEMM for that movement and the FEMM to be trained by adaptive neuro fuzzy inference system. During each iteration of training, Sensitivity of FEMM for training new movement information is reduced because the FEMM updated correctly. In test part, one movement among all movements that training in all FEMMs is selected and is done by...
The Scattering of Electro-Elastic Fields of an SH-Wave in a
Piezoelectric Medium by an Eccentric Two-Phase Circular
Piezoelectric Micro Sensor
,
M.Sc. Thesis
Sharif University of Technology
;
Mohammadi Shodja, Hossein
(Supervisor)
Abstract
This thesis presents an analytical solution for determination of the
electro-elastic media subjected to an anti plane shear harmonic wave containing a multi-phase cylindrical fiber whose electro-elastic properties differ from those of the matrix. Both the matrix and the coated-fiber system are transversely isotropic piezoelectric materials with symmetry and poling axes parallel to the fiber axis. The coating can have variable thickness. The dynamic electro-mechanical equivalent inclusion method (DEMEIM) is presented and employed as an extension of dynamic equivalent inclusion method (DEIM) in order to take into account the electro-mechanical coupling. Accordingly, the coating-fiber...
electro-elastic media subjected to an anti plane shear harmonic wave containing a multi-phase cylindrical fiber whose electro-elastic properties differ from those of the matrix. Both the matrix and the coated-fiber system are transversely isotropic piezoelectric materials with symmetry and poling axes parallel to the fiber axis. The coating can have variable thickness. The dynamic electro-mechanical equivalent inclusion method (DEMEIM) is presented and employed as an extension of dynamic equivalent inclusion method (DEIM) in order to take into account the electro-mechanical coupling. Accordingly, the coating-fiber...
Determination of Electro-elastic Fields in General Anisotropic Piezoelectric Mediums Due to Periodic and Non-periodic Distribution of Self-Assembled Quantum Wires and Quantum Dots
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Shoja, Hossein (Supervisor)
Abstract
Studying the behavior of piezoelectric materials containing self-assembled quantum wires and quantum dots is of great interest. This work is devoted to analytical and exact determination of the electro-elastic fields associated to quantum wires and quantum dots in piezoelectric mediums. The present work accounts for: (1) different shapes and orientations of quantum wires and quantum dots, (2) different types of anisotropy, and (3) high concentrations of quantum wires and quantum dots, that is, the corresponding interaction is considered properly. The presented solution is valid for general anisotropy and different shapes of quantum wires and quantum dots. In this work, periodic and...
Effective Shear Modulus of Elastic Solids Reinforced by Coated Elliptic Nanofibers in the Context of Couple Stress and Micropolar Theories
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Shodja, Hossein (Supervisor)
Abstract
Nowadays, by adding a small amount of a desired nanomaterial to a matrix having certain properties one may design a multifunctional nanocomposites with a remarkably improved macroscopic properties of interest. The capability of conventional continuum theories in treating the problems of embedded ultra-small inhomogeneity with any of its dimensions comparable to the characteristic lengths of the involved constituent phases is questioned, mainly, on the grounds of the accuracy and the size effect. In this work, effort is firstly directed at the prediction of the macroscopic shear modulus of composites consisting of nano-/micro-size fibers of elliptic cross-sections via couple stress theory, a...
A Formulation for the Characteristic Lengths FCC in First Gradient Elasticity Via Sutton-Chen Potential
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Shoja, Hossein (Supervisor)
Abstract
The usual continuum theories are inadequate in predicting the mechanical behavior of solids in presence of small defects and stress concentrators; it is well known that such continuum methods are unable to detect the change of the size of the inhomogeneities and defects. For these reasons various augmented continuum theories and strain gradient theories have been proposed in the literature. The major difficulty in implication of these theories lies in the lack of information about the additional material constants. For fcc metals, for calculation of the associated characteristic lengths which arise in first strain gradient theory, an ...
Ab initio DFPT Based Constitutive Modelling of Crystalline Solids within Micromorphic Theory with Application to Nano/Micro-structures
, Ph.D. Dissertation Sharif University of Technology ; Mohammad Shodja, Hossein (Supervisor)
Abstract
To account for certain essential features of material such as micro-structure effects and dispersive behaviour and optical branches in dispersion curves, a fundamental departure from classical elasticity to generalized continuum theories is required. Among the generalized continuum mechanics, micromorphic elasticity is capable of capturing these physical phenomena completely. In the mathematical framework of micromorphic elasticity, in addition to the traditional elastic moduli tensors, some additional tensors are introduced in the pertinent governing equations of motion. A precise evaluation of the numerical values of the aforementioned elastic moduli tensors in the realm of the...
Characterization of Mechanical Properties of Polymer Nanocomposites with Spherical Inhomogeneities
, M.Sc. Thesis Sharif University of Technology ; Naghdabadi, Reza (Supervisor) ; Bagheri, Reza (Supervisor)
Abstract
The improved properties of nanocomposites are not achievable with conventional composites. Scale effect is one the most important parameters in the physical and mechanical properties of polymeric nanocomposites. One of the physical phenomena, which can be related to the scale effect, is the very large interface between the nanoparticles and the polymeric matrices. Motional behavior and conformation of polymeric chains change near the nanoparticles surfaces. Due to high interface of the nanoparticles with the polymeric matrices the amount of these types of changes in the polymeric chains are so large that can change the physical and mechanical properties of polymeric nanocomposites. In this...
Estimation of the Price Elasticity of Gasoline Smuggling Demand in Iran
, M.Sc. Thesis Sharif University of Technology ; Rahmati, Mohammad Hossein (Supervisor)
Abstract
This study investigates the price elasticity of gasoline smuggling demand in Iran. For this purpose, a panel data of monthly gasoline consumption has been used that contains data for 160 regions of distribution for Iran's Oil Production Company between 2005 and 2014. The results of estimating the monthly elasticity of gasoline smuggling demand in each region show a significant impact of the gasoline price differential between Iran and its neighboring countries, as well as the distance of each region with the neighboring countries on the demand. The results of this study show that whenever gasoline prices increase inside the country, the inclination to smuggling has been decreased due to a...
Household Electricity Demand Estimation: A Regression Discontinuity Design Approach
, M.Sc. Thesis Sharif University of Technology ; Vesal, Mohammad (Supervisor) ; Rahmati, Mohammad Hossein (Supervisor)
Abstract
Estimating electricity demand elasticity in different sectors has been an essential research topic. Considering the fact that pricing electricity in various countries does not follow the same rules, many econometrics methods have been developed to estimate this crucial parameter. Electricity demand elasticity is defined as the percent change in electricity consumption in response to one percentage change in electricity price. Having a correct estimate of this parameter would help policymakers to price electricity properly in order to reach desirable goals in electricity consumption optimization and many other aspects of electricity consumption. In Iran, Tavanir Co. which is a subsidiary of...
Estimating Price Elasticity of Gasoline Demand Using Transaction-Level Data
, M.Sc. Thesis Sharif University of Technology ; Vesal, Mohammad (Supervisor) ; Rahmati, Mohammad Hossein (Supervisor)
Abstract
One of the most widely discussed parameters in energy economics is the price elasticity of gasoline demand due to its substantial implications for taxation, energy efficiency, and environmental policies. This paper aims to estimate the price elasticity of gasoline demand using a novel source of data. The data is from Iran, in the early months of 2014. Vehicles get a quota of 60 liters per month as subsidized gasoline at a lower price. The quota is transferable to the next months if it has not been consumed. All of the information about each pumping transaction is gathered in a centralized database, assigning a unique fuel card to each vehicle. Consequently, the structure of the market provides...
Estimating Income Elasticity of Household Energy Using the Quantile Regression Method
, M.Sc. Thesis Sharif University of Technology ; Madanizadeh, Ali (Supervisor)
Abstract
Abstract In this study, by using panel instrumental variable quantile regression method (IVQP) and household budget data during the years 2011-2018, income elasticity of Housing energy has been estimated at different levels of energy expenditure. This method helps to study the whole energy expenditure distribution instead of focusing on the average effects. The study results show that income elasticity has a downward trend with increasing energy consumption quantiles. In other words, households with higher consumption have less income elasticity, so that the income elasticity is estimated for 10, 90 percentage, 0.47, and 0.32 quantiles, respectively. Also, in another part of the research,...
Estimation Elasticity of Calorie and Macronutrients with Respect to Income in the Islamic Republic of Iran, 2008-2016
, M.Sc. Thesis Sharif University of Technology ; Vesal, Mohammad (Supervisor)
Abstract
Inadequate nutrition is perhaps the most important problem facing the poor. Being hungry lowers productivity and decreases individuals’ income. All of these factors conspire to help the poor stay poor. Raising the income of the poor is one solution for this problem if the elasticity of calorie and macronutrients with respect to income is greater than zero. This study employs both nonparametric and parametric methods to obtain the elasticity of per capita calorie and macronutrients with respect to household per capita expenditure. The case presented is for urban areas of Islamic republic of Iran, 2008-2016. Under each estimation strategy we employ, we find a strongly significant and positive...
Estimating Demand Elasticity of Tap30 Company
, M.Sc. Thesis Sharif University of Technology ; Madanizadeh, Ali (Supervisor) ; Joshaghani, Hosein (Supervisor)
Abstract
Access to the data of Tap30, a ride-hailing company in Iran, has allowed us to estimate the demand elasticity of online taxis. As Tap30 divides Tehran into 256 regions for pricing from Jan to June 2018, we assumed that unobservable consumer characteristics near borders are the same for adjacent regions. We used the Regression Discontinuity method to compare ride requests of people who live on two sides of borders and estimated the demand elasticity of Tap30. This research concludes that by 10 percent increase in price, the demand decreases about 3.5 percent on average in 1 hour time period. On the other hand, in 6 hours time period, the demand decreases about 7.5 percent on average by 10...
Estimating The Demand of Freeways in Iran, Using Discreet Choice Model
, M.Sc. Thesis Sharif University of Technology ; Rahmati, Mohammad Hossein (Supervisor) ; Vesal, Mohammad (Supervisor)
Abstract
According to the principle No. 44 of the Constitution of the Islamic Republic of Iran, Roads are in the public domain and are at the discretion of the Government. The result of this rule is that there is always a free route on the side of the freeway and motorists have the right to choose between a freeway and its successor road. This is a perfect laboratory condition which gives the opportunity that can be used with discrete choice models to estimate the demand of freeway versus its successor. In this paper we estimate the determinant parameters of the freeway demand versus the successor road and price elasticity of demand that can be calculated separately for each path. The results show...
Estimating Demand Function for Antihypertensives in Iran
, M.Sc. Thesis Sharif University of Technology ; Fatemi Ardestati, Farshad (Supervisor)
Abstract
The essential need for allocation of appropriate resources to the wellbeing and medication plans in a society can be understood from the fundamental impact of health on the performance of the labor force of the society, which can lead to significant increase in the economic growth rate. The high costs associated with research and development make pharmaceutical industry owners to be very vigilant about their investment on new drugs and expected sales. The purpose of this study is to evaluate current Iranian market for a part of Antihypertensive drugs and to estimate the demand for this group of drugs. The method used to obtain the estimation involved multi-stage budgeting, which benefits...
Planning Latency-Aware Multilayer IP-over-Elastic Optical Networks Supporting Various Survivability Mechanisms
, M.Sc. Thesis Sharif University of Technology ; Salehi, Javad (Supervisor) ; Beyranvand, Hamzeh (Supervisor)
Abstract
The growth of traffic in metro and core networks is not deniable today, in addition to the volume of traffic, their different requirement force operators to dimension IP over optical network for the peak traffics and also cares about requirements of the traffics. this multi-policy enabled network using new extended technology such as Elastic Optical Network and Bandwidth variable transponders is used to design network with minimum cost and resource. There is different quality of service parameter, in this work we focus on end to end latency and survivability. we present ILP formulation for the IP over elastic optical network and introduce these parameters to this formulation, as we know...
Resource Allocation and Optical Amplification in Elastic Optical Networks
, M.Sc. Thesis Sharif University of Technology ; Pakravan, Mohammad Reza (Supervisor)
Abstract
Diversity of new traffic patterns, due to new applications such as cloud computing, online gaming, Internet of Things (IoT), and Video on Demand (VoD), have pushed more dynamic behavior and faster reconfiguration to traditional networks. Elastic Optical Network (EON) is a new concept to response these requirements. Spectrum efficiency will be increased by exploiting OFDM-based elastic optical network. As a result, increasing fiber nonlinear effects would be a consequence of compression of spectrum. Optical Amplifier is used in optical networks to compensate fiber loss along the optical path. Amplifiers placement, in most of papers, is considered fixed at the end of each invariant span. This...
3D Resource Allocation in Multi-Core Fibers
, M.Sc. Thesis Sharif University of Technology ; Salehi, Javad (Supervisor)
Abstract
High-definition video streaming, multimedia file sharing, cloud computing, mobile networks and online gaming, all together, will increase the network traffic enormously every year.Long-haul optical fiber networks form the backbone of the Internet and scaling to higher throughput and lower cost per bit is essential to ensure continued growth of information technologies. For four decades, optical networks have exploited significant progress in physical technologies, including low-loss single-mode fibers (SMFs), high-performance lasers and modulators, and low-noise optical amplifiers. In parallel, communication methods have evolved to multiplex information in various physical dimensions in...
Sability and Sibration Analysis for a Type of Special Nano Motor Based on Cylindrical Shell Equations and Nonlocal Elastisity Theory
, M.Sc. Thesis Sharif University of Technology ; Dehghani Firouzabadi, Rohollah (Supervisor) ; Haddadpour, Hassan (Co-Advisor)
Abstract
The present study investigates the vibrational behavior of a special type of nano-motor based on a thin cylindrical shell model and the nonlocal elasticity theory of Eringen. The presumed nano-motor is comprised of three single walled carbon nanotubes (CNT), where two of them are cantilevered and the third one is located in the middle. The CNT in the middle will suspend due to the Van-der-Waals forces generated from the interaction by the cantilevered CNT pair. Some proper chirality arrangements can conduct electricity and make the middle CNT rotate in extremely high speeds. In fact, the middle CNT rotates on a frictionless elastic foundation. In the present study, the nano-motor is modeled...