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    Optimal Use of Digital Tools and Technologies for Sustainability in Supply Chain Management

    , M.Sc. Thesis Sharif University of Technology Sehat, Alireza (Author) ; Haji, Alireza (Supervisor)
    Abstract
    The main purpose of this study was to investigate the optimal use of digital tools and technologies for sustainability in Supply Chain Management (SCM). To achieve this, we examined various discussions, including economic, ecological, social, legal policy, value, and technological factors related to Sustainable Supply Chain Management (SSCM). This thesis utilized a mixed-methods approach, incorporating qualitative analysis to identify and finalize the variables and measures of the research model through a systematic review of existing studies. The statistical analysis method employed SPSS software to examine relationships between variables, while structural equation modeling was conducted in... 

    Effect of Aquatic Plants Flexibility on Lateral and Vertical Dispersion

    , Ph.D. Dissertation Sharif University of Technology Sehat, Haleh (Author) ; Jamali, Mirmosadegh (Supervisor)
    Abstract
    Flexible vegetation has a significant impact on the small-scale hydrodynamics of aquatic environments, which governs the dispersion of dissolved and particulate material. Flexible canopies bend and oscillate in both the in-line and cross-flow directions due to periodic forcing associated with vortex shedding. The resultant plant motion affects the vegetation wake structure and, hence, the rate of lateral dispersion in these environments. Despite a recently-developed understanding of dispersion in rigid canopies, a framework that can predict the effect of plant-induced vibrations on mixing in flexible canopy environments is still lacking. Here, we investigate the role of the flexibility of... 

    Experimental study of internal forced convection of ferrofluid flow in porous media

    , Article Defect and Diffusion Forum ; Vol. 348 , April , 2014 , pp. 139-146 ; ISSN: 10120386 ; ISBN: 9783038350002 Sehat, A ; Sadrhosseini, H ; Shafii, M. B ; Sharif University of Technology
    2014
    Abstract
    This work presents an experimental study of the effect of a magnetic field on laminar forced convection of a ferrofluid flowing in a tube filled with permeable material. The walls of the tube are subjected to a uniform heat flux and the permeable bed consists of uniform spheres of 3-mm diameter. The ferrofluid synthesis is based on reacting iron (II) and iron (III) in an aqueous ammonia solution to form magnetite, Fe3O4. The magnetite is mixed with aqueous tetra methyl ammonium hydroxide, (CH3) 4NOH, solution. The dependency of the pressure drop on the volume fraction, and comparison of the pressure drop and the temperature distribution of the tube wall is studied. Also comparison of the... 

    Aluminum-based metal-organic frameworks for adsorptive removal of anti-cancer (methotrexate) drug from aqueous solutions

    , Article Journal of Environmental Management ; Volume 277 , 2021 ; 03014797 (ISSN) Ahmadijokani, F ; Tajahmadi, S ; Rezakazemi, M ; Sehat, A. A ; Molavi, H ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
    Academic Press  2021
    Abstract
    A series of metal-organic frameworks (MOFs) based on aluminum-benzene dicarboxylates (MIL-53, NH2-MIL-53, and NH2-MIL-101) at different ratios have been synthesized, and their adsorption performances for methotrexate (MTX), an anti-cancer drug, have been investigated in terms of adsorption kinetics, isotherms, solution pH, thermodynamics, mechanism, and recyclability. Maximum adsorption values of 374.97, 387.82, and 457.69 mg/g were observed for MIL-53, NH2-MIL-53, and NH2-MIL-101, respectively. Our study shows that adsorption capacity of MTX depends not only on surface area and pore volume but also on the zeta potential and the presence of suitable functional groups. Higher adsorption of... 

    Aluminum-based metal-organic frameworks for adsorptive removal of anti-cancer (methotrexate) drug from aqueous solutions

    , Article Journal of Environmental Management ; Volume 277 , 2021 ; 03014797 (ISSN) Ahmadijokani, F ; Tajahmadi, S ; Rezakazemi, M ; Sehat, A. A ; Molavi, H ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
    Academic Press  2021
    Abstract
    A series of metal-organic frameworks (MOFs) based on aluminum-benzene dicarboxylates (MIL-53, NH2-MIL-53, and NH2-MIL-101) at different ratios have been synthesized, and their adsorption performances for methotrexate (MTX), an anti-cancer drug, have been investigated in terms of adsorption kinetics, isotherms, solution pH, thermodynamics, mechanism, and recyclability. Maximum adsorption values of 374.97, 387.82, and 457.69 mg/g were observed for MIL-53, NH2-MIL-53, and NH2-MIL-101, respectively. Our study shows that adsorption capacity of MTX depends not only on surface area and pore volume but also on the zeta potential and the presence of suitable functional groups. Higher adsorption of... 

    The impact of plant oscillation on dispersion in emergent aquatic canopies

    , Article Water Resources Research ; Volume 59, Issue 3 , 2023 ; 00431397 (ISSN) Sehat, H ; Abdolahpour, M ; Jamali, M ; Ghisalberti, M ; Sharif University of Technology
    John Wiley and Sons Inc  2023
    Abstract
    Flexible canopies bend and oscillate in both the in-line and cross-flow directions due to periodic forcing associated with vortex shedding. The resultant plant motion impacts the vegetation wake structure and, thus, the rate of lateral dispersion in these environments. Despite significant improvements in our understanding of dispersion in rigid canopies, a reliable framework to predict mixing in oscillating canopies is still lacking. This research demonstrates how plant oscillation can profoundly impact rates of lateral mixing in steady flows. The lateral dispersion coefficients were evaluated experimentally, using photographs of injected dye plumes within two types of emergent flexible... 

    Environmental impact analysis of high-rise buildings for resilient urban development

    , Article Scientia Iranica ; Volume 27, Issue 4 , 2020 , Pages 1843-1857 Vafai, H ; Parivar, P ; Sehat Kashani, S ; Farshforoush Imani, A ; Vakili, F ; Ahmadi, G ; Sharif University of Technology
    Sharif University of Technology  2020
    Abstract
    In recent years, the construction of high-rise buildings as an urban development strategy has been accepted in many megacities. High-rise buildings have positive as well as negative impacts on urban environments. Therefore, the environmental impact assessment of high-rise buildings for establishing strategies to ensure sustainable and resilient urban development is essential. In this study, the environmental impact of high-rise buildings with a resilient development mindset was assessed. Resilience mindset provides an approach for including the uncertainties and interdependence of systems and processes for planning new sustainable developments and assessment methods. The corresponding... 

    Experimental Study of Internal Forced Convection of Ferrofluid Flow in Porous Media

    , M.Sc. Thesis Sharif University of Technology Sehat, Ashkan (Author) ; Sadrhosseini, Hani (Supervisor) ; Shafii, Mohammad Behshad (Co-Advisor)
    Abstract
    The present work illustrates the results of an experimental study of ferrofluid flow in a tube subjected to a constant heat flux on its wall and filled with permeable material under the effect of magnetic field. The aim of this project is investigating the enhancement of heat transfer and obtaining a uniform temperature distribution inside the pipe. In order to achieve this, a porous medium with a porosity of 0.39 and ferrofluid with volume fractions of 0.6, 1.0 and 1.5 are used simultaneously, in the presence of magnetic field. The experiments are held for four different Reynolds numbers of 147.1, 167.3, 184.3 and 205.1. Also, four various modes of the oscillatory magnetic field are applied... 

    Unraveling Legal Complexities: Muslim and non-Muslim Estate Administration Process in Malaysia and Brunei

    , Article De Jure: Jurnal Hukum dan Syar'iah ; Volume 16, Issue 2 , 2024 , Pages 531-554 ; 20851618 (ISSN) Nasrul, M. A. D ; Alihan, A. A ; Hamid, A. A. A ; Sultan, B ; Sharif University of Technology
    2024
    Abstract
    Estate administration involves managing and distributing a deceased individual’s assets to beneficiaries, as well as managing the liabilities. This process comprises legal, financial, and administrative tasks that ensure assets are transferred based on the deceased's wishes and in accordance with the law. In Southeast Asia countries such as Indonesia, Malaysia and Brunei where Muslims represents the majority of population, the Islamic law plays an integral part in the inheritance management as the process to be in line with the Islamic teachings and principle. The role of the syariah authority namely the syariah courts is prevalent and therefore, abidance to the rule under the syariah legal... 

    Intelligent semi-active vibration control of eleven degrees of freedom suspension system using magnetorheological dampers

    , Article Journal of Mechanical Science and Technology ; Volume 26, Issue 2 , 2012 , Pages 323-334 ; 1738494X (ISSN) Zareh, S. H ; Sarrafan, A ; Khayyat, A. A. A ; Zabihollah, A ; Sharif University of Technology
    2012
    Abstract
    A novel intelligent semi-active control system for an eleven degrees of freedom passenger car's suspension system using magnetorheological (MR) damper with neuro-fuzzy (NF) control strategy to enhance desired suspension performance is proposed. In comparison with earlier studies, an improvement in problem modeling is made. The proposed method consists of two parts: a fuzzy control strategy to establish an efficient controller to improve ride comfort and road handling (RCH) and an inverse mapping model to estimate the force needed for a semi-active damper. The fuzzy logic rules are extracted based on Sugeno inference engine. The inverse mapping model is based on an artificial neural network... 

    Performance and exhaust emission characteristics of a spark ignition engine operated with gasoline and CNG blend

    , Article Proceedings of the Spring Technical Conference of the ASME Internal Combustion Engine Division ; 2012 , Pages 179-187 ; 15296598 (ISSN) ; 9780791844663 (ISBN) Dashti, M ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
    2012
    Abstract
    Using CNG as an additive for gasoline is a proper choice due to higher octane number of CNG enriched gasoline with respect to that of gasoline. As a result, it is possible to use gasoline with lower octane number in the engine. This would also mean the increase of compression ratio in SI engines resulting in higher performance and lower gasoline consumption. Over the years, the use of simulation codes to model the thermodynamic cycle of an internal combustion engine have developed tools for more efficient engine designs and fuel combustion. In this study, a thermodynamic cycle simulation of a conventional four-stroke spark-ignition engine has been developed. The model is used to study the... 

    A comparative study of the performance of a SI engine fuelled by natural gas as alternative fuel by thermodynamic simulation

    , Article 2009 ASME Internal Combustion Engine Division Fall Technical Conference, ICEF 2009, Lucerne, 27 September 2009 through 30 September 2009 ; 2009 , Pages 49-57 ; 9780791843635 (ISBN) Dashti, M ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2009
    Abstract
    With the declining energy resources and increase of pollutant emissions, a great deal of efforts has been focused on the development of alternatives for fossil fuels. One of the promising alternative fuels to gasoline in the internal combustion engine is natural gas [1-5]. The application of natural gas in current internal combustion engines is realistic due to its many benefits. The higher thermal efficiency due to the higher octane value and lower exhaust emissions including CO2 as a result of the lower carbon to hydrogen ratio of the fuel are the two important feature of using CNG as an alternative fuel. It is well known that computer simulation codes are valuable economically as a cost... 

    Analytical and experimental analyses of nonlinear vibrations in a rotary inverted pendulum

    , Article Nonlinear Dynamics ; Volume 107, Issue 3 , 2022 , Pages 1887-1902 ; 0924090X (ISSN) Dolatabad, M.R ; Pasharavesh, A ; Khayyat, A. A. A ; Sharif University of Technology
    Springer Science and Business Media B.V  2022
    Abstract
    Gaining insight into possible vibratory responses of dynamical systems around their stable equilibria is an essential step, which must be taken before their design and application. The results of such a study can significantly help prevent instability in closed-loop stabilized systems by avoiding the excitation of the system in the neighborhood of its resonance. This paper investigates nonlinear oscillations of a rotary inverted pendulum (RIP) with a full-state feedback controller. Lagrange’s equations are employed to derive an accurate 2-DoF mathematical model, whose parameter values are extracted by both the measurement and 3D modeling of the real system components. Although the governing... 

    A suction-controlled ring device to measure the coefficient of lateral soil pressure in unsaturated soils

    , Article Geotechnical Testing Journal ; Volume 44, Issue 1 , 2020 Pirjalili, A ; Garakani, A. A ; Golshani, A ; Mirzaii, A ; Sharif University of Technology
    ASTM International  2020
    Abstract
    A suction-controlled ring device has been developed to continuously measure the coefficient of lateral soil pressure in deformable unsaturated soil samples from the at-rest to the active condition under application of increasing vertical pressure and controlled matric suction. The device incorporates a thin aluminum specimen ring equipped with horizontal strain gages for recording the lateral soil strains. In addition, a sensor recording water volume changes is utilized to continuously monitor the degree of saturation of the soil sample during tests. The matric suction within the soil texture is controlled using the axis translation technique. In order to verify the performance of the ring... 

    Gum tragacanth gels as a new supporting matrix for immobilization of whole-cell

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 24, Issue 4 , 2005 , Pages 1-7 ; 10219986 (ISSN) Otady, M ; Vaziri, A ; Seifkordi, A. A ; Kheirolomoom, A ; Sharif University of Technology
    2005
    Abstract
    We introduce a new smooth, non-toxic, biocompatible method for cross-linking of gum tragacanth (GT), a polysaccharide of natural origin, in order to serve as a new supporting matrix for immobilization systems. The modified gum is used as a matrix for the catalysis of the conversion of benzyl penicillin to 6-aminopenicillanic acid (6-APA) by means of Escherichia coli ATCC11105 with penicillin G acylase (PGA) activity. The results show that GT beads can not only serve as a proper matrix for immobilization, but show enhanced hydrolysis rate and stability compared to other immobilization systems used for this reaction. This signifies the potential of GT as a biocompatible matrix for... 

    True Class-E Design For Inductive Coupling Wireless Power Transfer Applications

    , Article 30th International Conference on Electrical Engineering, ICEE 2022, 17 May 2022 through 19 May 2022 ; 2022 , Pages 864-868 ; 9781665480871 (ISBN) Haeri, A. A. R ; Safarian, A ; Fotowat Ahmady, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    The Class-E power amplifier has been widely studied and formulated in the literature. Although the majority of reported inductive coupling wireless power transfer (WPT) systems use a class-E power amplifier for driving the primary coil, still there is a lack of a comprehensive study on class-E circuit dedicated to WPT, providing a set of closed form design equations for proper class-E operation. This paper presents the required design equations needed to design a 'true' class-E circuit for WPT applications. Equations for the series-tuned secondary coil WPT system are presented, as well as two different design procedures for the parallel-tuned secondary coil. The derived equations have been... 

    Crashworthiness determination of side doors and B pillar of a vehicle subjected to pole side impact

    , Article Applied Mechanics and Materials ; Vol. 663, issue , 2014 , p. 552-556 Lilehkoohi, A. H ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
    2014
    Abstract
    Pole Side Impact Tes is one out of three crash tests described by Euro NCAP standard for star rating of a vehicle and is required for assessing the Adult Occupant Protection. In this paper the goal is to determine the crashworthiness of side doors and B pillar in a Pole Side Impact Test based on Euro New Car Assessment Program (Euro-NCAP) using computer and simulation method. In this matter, a vehicle model has been prepared and meshed using Hypermesh and CATIA. The velocity of 29 km/h has been assigned to the vehicle which was on top of a cart while the pole has been assigned as a rigid static object based on Euro NCAP requirements specifically. Results show that different amounts of energy... 

    Investigation of Thickness Influences On Energy Absorption For Side Doors And B Pillar In Euro NCAP Pole Side Impact Test

    , Article Applied Mechanics and Materials ; Vol. 663, issue , Oct , 2014 , p. 585-589 Lilehkoohi, A. H ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
    2014
    Abstract
    To assess a car under the Euro New Car Assessment Program (Euro-NCAP), Adult Occupant Protection is one out of three parameters which need to be calculated with a weight factor of 50% while the other parameters, Child Occupant Protection and Pedestrian Occupant Protection, have a weight factor of 20%. The Pole Side Impact Test, beside two other tests, Side and Front Impact, is also required to calculate the Adult Occupant Protection. It shows how important the Pole Side Impact Test is and what an effective role it has in the car rating assessment. In this paper, the objective is to evaluate the effect of thickness on the energy absorbed by the side doors and the B pillar and its... 

    Crashworthiness determination for front and rear doors and B pillar subjected to side impact crash by a mobile deformable barrier

    , Article Advanced Science Letters ; Volume 19, Issue 2 , 2013 , Pages 392-395 ; 19366612 (ISSN) Lilehkoohi, A. H ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
    2013
    Abstract
    In Euro NCAP standard, adult protection is one of the most important rating scores with 50% weight factor while child protection and pedestrian protection are accounted into consideration with 20% weight factor. For adult protection testing, three tests are required to perform: (1) side impact, (2) pole impact, (3) front impact. In the side impact test, dummy's head, chest, shoulder, thorax, ribs, abdomen, pelvic and femur must be studied to evaluate the rating score. Crashworthiness of a car during side impact can describe the score rated for that car. In this paper the goal is to determine the crashworthiness of side doors and B-pillar in side impact crash est by simulation using LS DYNA... 

    Effect of material and thickness of side doors and B pillar on crashworthiness in euro NCAP side impact crash test

    , Article Advanced Science Letters ; Volume 19, Issue 2 , 2013 , Pages 420-424 ; 19366612 (ISSN) Lilehkoohi, A. H ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
    2013
    Abstract
    In side impact test which is one out of three tests of Euro NCAP standard, front and rear doors and B pillar are most absorbance parts among vehicle body parts. Passengers are highly in danger while side crash, because of the distance between passenger's head and vehicle body. In this paper effect of material and thickness of doors and B-pillar and their absorbed energy during crash and improvement of its crashworthiness with respect to light weight design are studied using LS DYNA solver. The objective of this paper is to propose a material for doors and B-pillar with a specified thickness to achieve maximum absorbed energy and minimum weight. The shape of the doors and B-pillar remains...