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    Analytical Solution of Two Layered Flow in Transition to Approach Controlled Flow

    , M.Sc. Thesis Sharif University of Technology Ghazi Nezami, Arefeh (Author) ; Jamali, Mirmosadegh (Supervisor)
    Abstract
    In nature, tidal currents are visible in gorges and in saltwater and freshwater collisions. In the study of behavior of different types of flow, it is usually assumed that the pressure is hydrostatic and the equations are solved based on this assumption. In the Approach Controlled regime observed during the double layer in 1993, the modeling performed using the equations derived from this assumption did not fit the results of the experiments. This demonstrates the inability of the hydrostatic pressure assumption to solve this particular regime. Hence, the equations were written on the basis of non-hydrostatic pressure and then the observed results were in accordance with the results of the... 

    Investigation of Non-Universal Corrections to Topologically Quantized Conductance using Anomaly Inflow

    , Ph.D. Dissertation Sharif University of Technology Ghazi, Armin (Author) ; Jafari, Akbar (Supervisor)
    Abstract
    In this thesis, we study the fate and consequences of the existence of edges or domain walls with non-zero thickness and how the properties of edge modes arising from symmetry-protected topological (SPT) phases and consequently the bulk dynamics of these phases changes due to this thickness. This general study is specifically examined in the context of anomalous quantum Hall effect (QAHE) systems as an example of these topological phases. Symmetry-protected topological phases are an important category of gapped material topological phases that, although lacking long-range order, exhibit non-trivial properties in the presence of boundaries. These non-trivial properties arise due to the... 

    Patient Scheduling under Uncertainty and Hospital Resource Allocation with Patient Waiting Time, Personnel Overtime and Idleness Minimization Approach and with Application of Queuing Theory and Analytical Tools

    , M.Sc. Thesis Sharif University of Technology Mirmajidi Nezami, Ali (Author) ; Shadrokh, Shahram (Supervisor)
    Abstract
    Scheduling problem specially surgery room scheduling is noteworthy and well known in optimization and machine learning literature which improve resource usage means cost reduction and patient experience means satisfaction increase.Surgery Rooms are one of the most costly section of the hospital. In addition to this, Surgeon are expensive resource and all the hospitals have limited capacity. By scheduling we can improve patient’s experience and resource management. That’s why scheduling Surgery Room is important and noteworthy.In this research we consider surgery duration and patient length of stay(LOS) probabilistic. Our approach for handling this is stochastic programming in which our... 

    Evaluation of ceramic/ceramic joint interface prepared via brazing

    , Article Materials Forum, 18 October 2011 through 20 October 2011 ; Volume 35 , October , 2011 , Pages 20-30 ; 08832900 (ISSN) ; 9781876855369 (ISBN) Ghazi Daryani, A ; Nemati, A ; Sharif University of Technology
    2011
    Abstract
    Recent investigations show that ceramic/ceramic joints have high potential for applications in industry. Cost and difficulty in manufacturing complex components, either in one step or by joining of ceramic-metal and ceramic-ceramic, have inhibited more widespread use. It is important to know how to join components without problems and to understand the role of the interface as the main factor controlling the properties in these joints. The purpose of this paper was to investigate the joining of two ceramics with metal fillers (SiC to SiC and Al2O3 to Al2O3) and to investigate the interface of SiC/SiC and Al2O3/Al 2O3 with the same metal interlayer (Ag-Cu-Ti) and the effects on the... 

    Dynamic diversity enhancement in particle swarm optimization (DDEPSO) algorithm for preventing from premature convergence

    , Article Procedia Computer Science ; Volume 24 , 2013 , Pages 54-65 ; ISSN: 18770509 Nezami, O. M ; Bahrampour, A ; Jamshidlou, P ; Sharif University of Technology
    2013
    Abstract
    The problem of early convergence in the Particle Swarm Optimization (PSO) algorithm often causes the search process to be trapped in a local optimum. This problem often occurs when the diversity of the swarm decreases and the swarm cannot escape from a local optimal. In this paper, a novel dynamic diversity enhancement particle swarm optimization (DDEPSO) algorithm is introduced. In this variant of PSO, we periodically replace some of the swarm's particles by artificial ones, which are generated based on the history of the search process, in order to enhance the diversity of the swarm and promote the exploration ability of the algorithm. Afterwards, we update the velocity of the artificial... 

    A Survey on kant's Universal Law: Parfit, Scanlon

    , M.Sc. Thesis Sharif University of Technology Mirzaei Ghazi, Shervin (Author) ; Azadegan, Ebrahim (Supervisor)
    Abstract
    In his book “Groundwork for the Metaphysic of Morals ”, Kant tries to pesent a formula for the supreme pinciple of morality. He ends up introducing three formulae that he thinks are all the same and just pesenting one formula In three different ways. After publishing this book, many criticisms were levelled against both his way of argument and the efficacy of his proposed formulae. In this enquiry, by focusing on the first two chapters of Kant’s book, and by considering the universal law formula and the humanity formula, we try to answer these criticisms. In the way, we make use of the new reading of Kant’s view- the critical reading- proposed by Samuel Kerstein, according to which Kant’s... 

    Assessment of the Hydro-Mechanical and Shear Behavior of Collapsible Soils by Using Suction- Controlled Triaxial Apparatus- A Case Study: Loess of Gorgan

    , M.Sc. Thesis Sharif University of Technology Ghazi Zadeh, Shahin (Author) ; Haeri, Mohsen (Supervisor)
    Abstract
    In geotechnical engineering, collapsible soils as a part of problematic soils has an extreme importance since as a mutual effects of applying load and increasing their water content, Soil’s inter-particle forces become weak, and therefore, the soil experiences sudden large volumetric change known as collapse. Foundations built on these soils might experience sudden, large settlement. Collapsible soils exist in almost all continents, and many damages are reported due to the collapse phenomenon of these soils.
    Due to the importance of this issue, and lack of comprehensive studies related to the volumetric and shear behavior of these soils, in this study, triaxial wetting test are performed... 

    ShEMO: a large-scale validated database for Persian speech emotion detection

    , Article Language Resources and Evaluation ; Volume 53, Issue 1 , 2019 ; 1574020X (ISSN) Mohamad Nezami, O ; Jamshid Lou, P ; Karami, M ; Sharif University of Technology
    Springer Netherlands  2019
    Abstract
    This paper introduces a large-scale, validated database for Persian called Sharif Emotional Speech Database (ShEMO). The database includes 3000 semi-natural utterances, equivalent to 3 h and 25 min of speech data extracted from online radio plays. The ShEMO covers speech samples of 87 native-Persian speakers for five basic emotions including anger, fear, happiness, sadness and surprise, as well as neutral state. Twelve annotators label the underlying emotional state of utterances and majority voting is used to decide on the final labels. According to the kappa measure, the inter-annotator agreement is 64% which is interpreted as “substantial agreement”. We also present benchmark results... 

    ShEMO: a large-scale validated database for persian speech emotion detection

    , Article Language Resources and Evaluation ; 2018 ; 1574020X (ISSN) Nezami, O. M ; Jamshid Lou, P ; Karami, M ; Sharif University of Technology
    Springer Netherlands  2018
    Abstract
    This paper introduces a large-scale, validated database for Persian called Sharif Emotional Speech Database (ShEMO). The database includes 3000 semi-natural utterances, equivalent to 3 h and 25 min of speech data extracted from online radio plays. The ShEMO covers speech samples of 87 native-Persian speakers for five basic emotions including anger, fear, happiness, sadness and surprise, as well as neutral state. Twelve annotators label the underlying emotional state of utterances and majority voting is used to decide on the final labels. According to the kappa measure, the inter-annotator agreement is 64% which is interpreted as “substantial agreement”. We also present benchmark results... 

    A novel hybrid systemic modeling into sustainable dynamic urban water metabolism management: Case study

    , Article Sustainable Cities and Society ; Volume 85 , 2022 ; 22106707 (ISSN) Nezami, N ; Zarghami, M ; Tizghadam, M ; Abbasi, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Over the past few years, due to increasing population, limited water resources, and other pressures on the urban water systems (UWS), urban water management has become a major concern for urban policymakers to develop efficient management solutions. In this study, a new hybrid model called sustainable dynamic urban water metabolism management (SDUWMM) is presented, based on urban water metabolism and system dynamics. Isfahan's UWS has been modeled by SDUWMM and its conditions have been simulated until 2041. SDUWMM considers effective internal relationships of the UWS components such as population, climate change, water supply and demand, infrastructures condition, water price, costs and... 

    Quantifying the Social Impacts of Infrastructure Systems Failure for Community Resilience Analysis

    , M.Sc. Thesis Sharif University of Technology Eshghi Nezami, Mohammad Amin (Author) ; Kashani, Hamed (Supervisor)
    Abstract
    The purpose of this study is to present a suitable model for calculating the costs imposed on society due to deaths and injuries due to infrastructure failure due to earthquakes, which is used in the analysis of community resilience. Much research has been done to date to calculate the economic costs of infrastructure failure. However, no suitable analytical framework has been provided to quantify the costs of deaths and injuries to people due to earthquake failure. Previous research has provided methods such as the value of statistical life to quantify the social costs caused by accidents and environmental pollution. However, the literature review results in the field of seismic resilience... 

    Numerical study of enhanced heat transfer by coupling natural and electro-convections in a horizontal enclosure

    , Article Journal of Enhanced Heat Transfer ; Volume 18, Issue 6 , 2011 , Pages 503-511 ; 10655131 (ISSN) Ghazi, R ; Saidi, M. S ; Saidi, M. H ; Sharif University of Technology
    2011
    Abstract
    The heat transfer enhancement of natural convection using an electrohydrodynamic technique inside a horizontal enclosure heated from below is studied numerically. The interactions between the electric field, flow field, and temperature field are investigated by computational fluid dynamics methods. The flow and temperature fields are affected by voltage applied to the wire electrodes. For different voltages and numbers of electrodes, it is noticed that the Nusselt number increases in all cases and the best enhancement is obtained at lower Rayleigh numbers. It is also shown that increasing the number of electrodes does not always cause an increase in the heat transfer enhancement. Actually,... 

    Developing of constructal theory concept to the total site cogeneration heat and power retrofit

    , Article International Journal of Exergy ; Volume 17, Issue 2 , 2015 , Pages 171-191 ; 17428297 (ISSN) Ghazi, M ; Amidpour, M ; Abbaspour, M ; Farzaneh, H ; Sharif University of Technology
    Inderscience Enterprises Ltd  2015
    Abstract
    In this paper, a novel method of retrofit design in total site cogeneration systems based on constructal theory is presented. In this regard, the total site cogeneration system is decomposed into three constructs: turbines, turbine arrays, and steam generators. The objective function to be minimised is the total annual cost of existing total site. Using constructal theory simplifies the optimisation procedure of total site in addition to reaching better conceptual design especially in more sophisticated systems. A case study from literatures has been taken up to examine the applicability of the algorithm and excellent agreement has been observed. Copyright  

    Numerical study of AN ion injection EHD micropump

    , Article Proceedings of the 7th International Conference on Nanochannels, Microchannels, and Minichannels 2009, ICNMM2009, 22 June 2009 through 24 June 2009 ; Issue PART A , 2009 , Pages 179-185 ; 9780791843499 (ISBN) Ghazi, R ; Saidi, M. S ; Saidi, M. H ; Sharif University of Technology
    2009
    Abstract
    The purpose of this study is to carry out a numerical investigation of injection type EHD pumps. To this end, the flow is considered laminar, steady and incompressible flow. The flow model is based on the assumptions that the fluid is Newtonian and the fluid properties are constant. The results show that all of the ions emitted from emitter are not collected by next collector electrode, but some of this injected ions move to the previous one, which causes back flow. Although this back flow is smaller than net pumping flow but it would reduce the net flow. Because of existence of this back flow, finding the optimum distance of electrodes from each other is necessary. This study shows that... 

    Sensor-Less Control of Permanent Magnet Synchronous Motor Using High Frequency Signal Injection

    , M.Sc. Thesis Sharif University of Technology Ghazi Moghadam, Mohammad Ali (Author) ; Tahami, Farzad (Supervisor)
    Abstract
    In this thesis one of the sensorless methods which exploits the existing anisotropies of the rotor is utilized to estimate rotor position. In order to implement this method, first a high frequency voltage is injected in a specific, time-varying direction and then the corresponding current response would be observed in order to estimate the rotor saliency position. The estimation of rotor position would be more precise as the magnetic anisotropy due to rotor saliency increases and as a result the effect of noise and different disturbances in estimation of rotor position would be decresed. The effect of stator resistence is one of these disturbances which is usually neglected as a result of... 

    Electrode arrangement effect on natural convection in a horizontal enclosure

    , Article ASME 2009 7th International Conference on Nanochannels, Microchannels, and Minichannels ; Issue PART A , 2009 , Pages 187-196 ; 9780791843499 (ISBN) Ghazi, R ; Saidi, M. S ; Saidi, M. H ; ASME ; Sharif University of Technology
    2009
    Abstract
    The heat transfer enhancement of natural convection, using electrohydrodynamic technique inside a horizontal enclosure heated from below, is studied numerically. The interactions between electric field, flow field, and temperature field are investigated by CFD methods. The flow and temperature fields are affected by voltage applied at the wire electrodes. For different voltages and number of electrodes, it is noticed that the Nusselt number increased in all cases and the best enhancement is obtained at lower Rayleigh numbers. It is also shown that increasing the number of electrodes doesn't always cause an increase in the heat transfer enhancement. Actually, when the number of electrodes is... 

    The impact of pavement permeability on time of concentration in a small urban watershed with a semi-arid climate

    , Article Water Resources Management ; Volume 34, Issue 9 , 2020 , Pages 2969-2988 Ghazi Zadeh Hashemi, M. S ; Tajrishy, M ; Jalilvand, E ; Sharif University of Technology
    Springer  2020
    Abstract
    Despite the popularity of the permeable pavements in urban areas in recent years, a few empirical equations have been developed to estimate the time of concentration (Tc) on pervious surfaces, and almost none of them is evaluated over the permeable pavements. In this paper, we aim to investigate the effect of low impact development (LID) on Tc and develop a new equation for estimating overland flow Tc compatible with both permeable and impermeable pavements in small urban watersheds with a semi-arid climate. An experimental model was devised to determine the new equation. Synthetic rainfall (22–40 mm.h−1) was applied to a rectangular shaped (6 m × 1 m) test watershed with an adjustable... 

    The Effect of Robot Assisted Language Learning (RALL) on Iranian EFL Junior High School Students’ Vocabulary Learning and Retention

    , M.Sc. Thesis Sharif University of Technology Ghazi Saedy, Maryam (Author) ; Alemi, Minoo (Supervisor) ; Meghdari, Ali (Co-Advisor)
    Abstract
    This study investigated the effect of Robot Assisted Language Learning (RALL) on the vocabulary learning and retention as well as anxiety and attitude of Iranian English as Foreign Language (EFL) junior high school students in Tehran-Iran. After taking a vocabulary pretest, 46 beginner level female students at the age of 12, studying in their first year of junior-high participated in two groups of RALL (30 students) and non-RALL (16 students) in this study. The textbook used was the English book (Prospect-1) devised by the Iranian Ministry of Education for 7th graders, and the vocabulary taught and tested (pretest and posttest) were taken from this book. Moreover, the treatment given by a... 

    Event-Triggered Adaptive Control of a Class of Uncertain Nonlinear Systems

    , Ph.D. Dissertation Sharif University of Technology Ghazi Saeedi, Hamid Reza (Author) ; Tavazoei, Mohammad Saleh (Supervisor)
    Abstract
    Considering uncertainty is of great importance in the design of controllers for dynamical systems because the existence of uncertainty is inevitable in the modeling of almost all real-world systems. There are numerous methods and strategies for dealing with the control of uncertain systems in control systems theory including adaptive and robust approaches. The former one is more suitable for cases in which the information about uncertainty is very poor compared to robust techniques that are applicable in the cases more data is available about uncertainty. For instance, where there is no data about the direction in the actuator model, adaptive control methods are the only applicable choices.... 

    Quantification of irrigation water using remote sensing of soil moisture in a semi-arid region

    , Article Remote Sensing of Environment ; Volume 231 , 2019 ; 00344257 (ISSN) Jalilvand, E ; Tajrishy, M ; Ghazi Zadeh Hashemi, S. A ; Brocca, L ; Sharif University of Technology
    Elsevier Inc  2019
    Abstract
    Irrigated agriculture is the principal consumer of fresh water resources. Most countries do not have a precise measurement of water consumption for irrigation. In this study, an innovative approach is proposed that allows for estimation of irrigation water use at the catchment scale based on satellite soil moisture data. To this end, the SM2RAIN algorithm, which had been originally developed for estimation of rainfall from the soil moisture observations, is adopted. The satellite soil moisture observations obtained from Advanced Microwave Scanning Radiometer 2 (AMSR2) along with different rainfall and evapotranspiration (ET) products in the period 2012–2015 are used as the input to the...