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    Iranian Household Saving Behavior

    , M.Sc. Thesis Sharif University of Technology Samaee, Kian (Author) ; Souri, Davood (Supervisor)
    This paper decomposes the saving rate into cohort, age and year effects. This objective is accomplished by constructing a pseudo-panel that amalgamates nineteen consecutive, cross-sectional Household Income and Expenditure Surveys from 1991 to 2009. To construct year-of-birth cohorts with consistent composition over time, analyses are limited to those born between 1926 and 1975. Results reveal that those belonging to younger cohorts save a higher fraction of their income relative to their predecessors at the same age. Moreover, the increase in the saving rate can not be explained by the significant decline in household size or rise in educational attainment among younger cohorts. Closer... 

    Fine-grained Image Classification

    , M.Sc. Thesis Sharif University of Technology Souri, Yaser (Author) ; Kasaei, Shohreh (Supervisor)
    Fine-grained image classification is image classification where the considered classes are all sub-classes of a certain, more general class. In this setting of the problem, the classes are visually very similar to each other, such that an unskilled human cannot discriminate between them. In this case, proposed methods for the ordinary image classification problem do not obtain good classification accuracy. So proposing new methods for solving this problem is necessary. In this thesis two new methods, based on recent advances in deep learning are proposed for solving the fine-grained image classification problem. First by improving several parts of one of the recent proposed methods for this... 

    Introduction of Concentric Braced Frame Equipped with BRB & YE (yielding element) and Quantification of Seismic Perfomance Factors
    Based on FEMA-P695

    , M.Sc. Thesis Sharif University of Technology Souri, Omid (Author) ; Mofid, Massoud (Supervisor)
    This investigation is intended to assess the behavior of SCBFs in the presence of typical brace members, which buckles in compression, and BRBs joining by yielding elements. While braces play a role in providing stiffness for structure, central yielding elements will act as energy-absorbing fuses. In this frame type, energy dissipation will mainly be undertaken by BRBs and yielding elements. The mentioned yielding elements do this by initiating plastic hinges in each corner of the central frame. As it is clear, designing a structure that includes the stated lateral-load-resisting system necessitates seismic performance parameters to be evaluated. Hence, by pursuing the FEMA P695 methodology,... 

    Modeling Spatial Variation of Housing Prices in Tehran (Zone8)

    , M.Sc. Thesis Sharif University of Technology MoniriJavid, Salimeh (Author) ; Souri, Davood (Supervisor)
    This study estimates a hedonic model for the price of housing in the city of Tehran. Using 1340 observations from the eighth region of the city as a sample and applying geographically weighted regression, the study shows that hedonic price function regardless of space variation in house price, leads to spatial autocorrelation in the error term of the model. Thus geographically weighted regression method can deal with this problem and is able to explain more than 76% of the variation in housing prices. Additionally, almost all three structural (floor area, kind of housing appearance and type of houses), environmental (distance from nearest hospital, park, school, health club and mosque) and... 

    Measuring Multidimensional Poverty Using Structural Equation Models

    , M.Sc. Thesis Sharif University of Technology Alinia, Parisa (Author) ; Souri, Davood (Supervisor)
    In order to measure poverty, researchers used to consider only the income and the financial aspect of poverty; however, further research has revealed that income in itself cannot be a proper and comprehensive index for measuring poverty, and other factors such as education, health, occupation, personal characteristics, cultural activities, political activities, etc. are also significant in determining the poverty index. Based on the information acquired from "household expenditure-income survey", this study tries to take into account all the factors affecting the poverty index, in four dimensions of economic well-being, capability, political participation and cultural participation. Poverty... 

    A Periodic Time Series Application in Housing Price Analysis (Case Study of Tehran)

    , M.Sc. Thesis Sharif University of Technology Shahhosseini, Mehrnoush (Author) ; Souri, Davoud (Supervisor)
    The seasonal fluctuations in economics variables relate to the different behavior of economic agents across different seasons. In past, seasonality has been viewed as a redundant feature that needs to be removed from data before economic analysis. From 1988, modeling seasonality has become the major concern of many economists; moreover, it was seen that many economic analysis and forecasts could be flawed if seasonality is ignored. In the present research, periodic times series approach is used for the first time in modeling the seasonality feature of the housing market. Regarding the importance of the housing sector in economy from micro and macroeconomic points of view, using a more... 

    Using Student’s t Autoregressive (STAR) to Model Financial Variables of Iran

    , M.Sc. Thesis Sharif University of Technology Fekrazad, Amir (Author) ; Souri, Davoud (Supervisor)
    Time series of asset returns display specific regularities such as bell-shaped distribution, leptokurticity and volatility clustering. Economists have made continuous efforts to develop models that explain these patterns and can be used to predict the return and the risk of holding an asset. These efforts can be classified into 3 eras: Bachelier Era (1900-1960) in which the random walk model was developed for speculative prices. Mandelbrot Era (1960-1980) in which the normality assumption was replaced with the Pareto-Levy family of distributions which are flexible enough to justify leptokurticity and infinite variance. And finally, the Dynamic Volatility era in which the focus was on... 

    Hot electron generation enhancement by long duration positive chirped laser pulses

    , Article Physica Scripta ; Volume 93, Issue 10 , 2018 ; 00318949 (ISSN) Souri, S ; Sadighi Bonabi, R ; Sharif University of Technology
    Interaction of the chirped circularly polarized laser pulse with ramped density plasma is presented by particle-in-cell simulation. The obtained results indicate that the laser penetration depth into the plasma target and hot-electron generation can be improved by chirped induced transparency (CIT). Positive chirped pulses penetrate more deeply in the plasma leading to the hot electron enhancement and improvement of the maximum separation accelerating fields at the rear side of the target. For laser pulse with 150 fs time duration, there is 40% increase in the laser penetration depth in the target and the maximum amount of the electrostatic field is improved by a factor of 5 in the present... 

    Methane Conversion to Higher and Valuable Hydrocarbons by Non-Thermal Plasma

    , M.Sc. Thesis Sharif University of Technology Souri, Somayeh (Author) ; Sadighi Bonabi, Rasol (Supervisor)
    Methane conversion into higher hydrocarbons has been investigated by non-thermal plasma. The most important advantages of utilizing this type of plasma are atmospheric pressure and ambient temperature of the operating system. In order to prepare non-thermal plasma, a spark discharge reactor has been used with the main prospect of acetylene production. Other components such as hydrogen, ethylene and ethane are also formed in the process as by-products. By optimizing the affecting parameters on methane conversion and products selectivity, maximum methane conversion of 83.2% is obtained. Acetylene yield varies between 25%-63% with input gas flow rate, voltage, frequency and discharge volume.... 

    Deep relative attributes

    , Article 13th Asian Conference on Computer Vision, ACCV 2016, 20 November 2016 through 24 November 2016 ; Volume 10115 LNCS , 2017 , Pages 118-133 ; 03029743 (ISSN); 9783319541921 (ISBN) Souri, Y ; Noury, E ; Adeli, E ; Sharif University of Technology
    Springer Verlag  2017
    Visual attributes are great means of describing images or scenes, in a way both humans and computers understand. In order to establish a correspondence between images and to be able to compare the strength of each property between images, relative attributes were introduced. However, since their introduction, hand-crafted and engineered features were used to learn increasingly complex models for the problem of relative attributes. This limits the applicability of those methods for more realistic cases. We introduce a deep neural network architecture for the task of relative attribute prediction. A convolutional neural network (ConvNet) is adopted to learn the features by including an... 

    Multidimensional Poverty Measurement of Iran (2004,2006)

    , M.Sc. Thesis Sharif University of Technology Alimadadi, Mohammad Sadegh (Author) ; Souri, Davood (Supervisor)
    In recent decades, many empirical issues have been accomplished about poverty respect to various dimensions of this phenomenon in micro level. At the start, monetary aspect of poverty was measured in uni-dimensional form but more researches result that poverty may be as a result of education level, health condition and other household characteristics; so multidimensional poverty indices were defined.The study employs the fuzzy-Set theoretic framework to compare levels of deprivation like income, housing, acquisition of durable goods, health condition, social security and education in Iran over time (2004, 2006) using micro data  

    Laser-driven proton acceleration enhancement by the optimized intense short laser pulse shape

    , Article Physics of Plasmas ; Volume 24, Issue 5 , 2017 ; 1070664X (ISSN) Souri, S ; Amrollahi, R ; Sadighi Bonabi, R ; Sharif University of Technology
    Interactions of two distinct shapes of the pulses namely positive/negative chirped pulse and fast/slow rising-edge pulse with plasma are studied using particle-in-cell simulation. It is found that, for a pulse duration of 34 fs and intensity a0 = 12, proton acceleration could be enhanced by asymmetric pulses with either pulse envelope or pulse frequency modification. The number of accelerated protons, as well as the proton energy cut-off, is increased by asymmetric pulses. In this work, for positive chirped pulse, electrostatic field at the rear side of the target is improved by about 30%, which in turns leads to an increase in the proton energy cut-off more than 40%. Moreover, in contrary... 

    Improvement of laser-driven proton beam quality by optimized intense chirped laser pulses

    , Article Physics of Plasmas ; Volume 25, Issue 1 , 2018 ; 1070664X (ISSN) Souri, S ; Amrollahi, R ; Sadighi Bonabi, R ; Sharif University of Technology
    American Institute of Physics Inc  2018
    The effect of pulse shaping on the intense laser-driven proton beam produced through radiation pressure acceleration as a highly efficient mechanism is investigated. In this regard, the interaction of pulses with modified frequencies, including positive and negative chirped pulses with plasma, is simulated using particle-in-cell code. The simulation results indicate that the proton acceleration could be significantly enhanced for both negative and positive chirped pulses. As a consequence of the acceleration time extension as well as the electron heating suppression, a sharper and narrower proton beam could be achieved for negative chirped pulses. The same trend is observed for all negative... 

    An Analysis of Private Health Insurance Purchasing Decisions
    Of Urban Households in Iran

    , M.Sc. Thesis Sharif University of Technology Hematy, Maryam (Author) ; Zamani, Shiva (Supervisor) ; Souri, Davoud (Supervisor)
    In order to better understand the performance of the Iranian health insurance industry, household decisions to purchase private health insurance are analyzed using a two-stage (Heckman) model on Survey of Family Income and Expenditure data. Probit and OLS regressions are used to examine the factors influencing the probability and amount of private health insurance purchased. Generally, factors affecting the probability of having insurance also influence the amount of insurance coverage purchased. The results show the importance of some demographics on the insurance decision, particularly age, gender and marital status. Socio-economic factors such as education, income, employment sector,... 

    Exaⅿpⅼes of Topoⅼogyⅽaⅼ Operaⅾs anⅾ Grassⅿⅿan Operaⅾs

    , M.Sc. Thesis Sharif University of Technology Souri, Ⅿarzieh (Author) ; Jafari, Aⅿir (Supervisor) ; Rastegar, Arash (Co-Supervisor)
    The projeⅽt first explores the ⅽonⅽept of operaⅾs anⅾ the basiⅽ ⅾefinitions of the theory suⅽh as the ⅾifferent ⅾefini− tions of operaⅾs ، anⅾ then expⅼores the types of exaⅿpⅼes of topoⅼogiⅽaⅼ operaⅾs anⅾ their properties anⅾ exaⅿines speⅽifiⅽaⅼⅼy the ⅽonstruⅽtion of the Grassⅿann props by us− ing the aⅼgebraiⅽ geoⅿetry tooⅼ anⅾ finally we ⅽoⅿpute the ⅽohoⅿoⅼogy group of Grassⅿann props by using the aⅼgebraiⅽ geoⅿetry tooⅼ anⅾ aⅼgebraiⅽ topology tool  

    Prediction of concrete compressive strength using a back-propagation neural network optimized by a genetic algorithm and response surface analysis considering the appearance of aggregates and curing conditions

    , Article Buildings ; Volume 12, Issue 4 , 2022 ; 20755309 (ISSN) Kashyzadeh, K. R ; Amiri, N ; Ghorbani, S ; Souri, K ; Sharif University of Technology
    MDPI  2022
    In the present research, the authors have attempted to examine the compressive strength of conventional concrete, which is made using different aggregate sizes and geometries considering various curing temperatures. To this end, different aggregate geometries (rounded and angular) were utilized in various aggregate sizes (10, 20, and 30 mm) to prepare 108 rectangular cubic specimens. Then, the curing process was carried out in the vicinity of wind at different temperatures (5◦ C < T < 30◦ C). Next, the static compression experiments were performed on 28-day concrete specimens. Additionally, each test was repeated three times to check the repeatability of the results. Finally, the mean... 

    Return Predictability and Volatility, and Spillovers of Indexes Using a Multivariate Dynamic Model in Tehran Stock Exchange

    , M.Sc. Thesis Sharif University of Technology Sanaei Alam, Mohsen (Author) ; Zamani, Shiva (Supervisor) ; Souri, Davood (Supervisor)
    Stock exchanges are one of the most important capital markets and let people and institutions to insvest their savings in stocks and therefore earn money. Investors are going to select a portfolio that has the maximum return and minimum risk; so, they try to forecast stock returns and volatilities. Predictability of stock return and volatility is also important for asset pricing and investigating market efficiency. Now, the question is “are stock returns and volatilities predictable using historical returns and volatilities?” In this research, return and volatility predictability of Tehran Stock Exchange indexes by using historical data are investigated. First, the outocorrelation of return... 

    Experimental Investigation and Comparison of Water Alternative Gas (WAG) and Continuous Gas Injection (CGI) Processes in One of Iranian Oil Reservoirs

    , M.Sc. Thesis Sharif University of Technology Souri Laki, Ali (Author) ; Ghotbi, Sirous (Supervisor) ; Kharrat, Reyaz (Supervisor)
    Gas injection processes are considered as the second largest Enhanced Oil Recovery processes after thermal processes. In Dealing with the problems of Continuous Gas Injection (CGI) processes, the substitute method of Water Alternating Gas (WAG) is gaining ever increasing attention in field applications. The Hybrid method has the advantages both CGI and WAG processes. Laboratory studies of gas injection methods to show the optimum method and the effect of pressure on the performance of this method is the main objective of this project. Results obtained from these tests can be used in the Enhanced Oil Recovery scenarios for this reservoir. In this project, experiments for Continuous Gas... 

    On the largest eigenvalue of signed unicyclic graphs

    , Article Linear Algebra and Its Applications ; Volume 581 , 2019 , Pages 145-162 ; 00243795 (ISSN) Akbari, S ; Belardo, F ; Heydari, F ; Maghasedi, M ; Souri, M ; Sharif University of Technology
    Elsevier Inc  2019
    Signed graphs are graphs whose edges get signs ±1 and, as for unsigned graphs, they can be studied by means of graph matrices. Here we focus our attention to the largest eigenvalue, also known as the index of the adjacency matrix of signed graphs. Firstly we give some general results on the index variation when the corresponding signed graph is perturbed. Also, we determine signed graphs achieving the minimal or the maximal index in the class of unbalanced unicyclic graphs of order n≥3. © 2019  

    Estimating Multidimensional Poverty Index for Iran in AF Method and Compuiting its Trend with Income Poverty Index

    , M.Sc. Thesis Sharif University of Technology Zarghami, Sahar (Author) ; Fatemi Ardestani, Farshad (Supervisor) ; Souri, Davood (Co-Supervisor)
    Because of the importance of the issue of poverty, in this study, we introduce and copute aspects & dimensions of multidimensional poverty index. The object of this thesis is studing the trend of changes in Iranian households’ welfare during the years 2005 through 2015 and recognizing the economic and social poor households’ characteristics. There are two methods that are used to computing MPI (Multidimensional Poverty Index). One of them is standard method that is given unique weight to each dimension, the other one is questionnaire method which is asked poverty experts to set proper weight to each dimension. Knowing how poverty index (income & mpi) changes, can help policy makers to...