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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... 

    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... 

    Sustainable-Resilient Supplier Selection Through Fuzzy Multi-Criteria Decision Making Approaches

    , M.Sc. Thesis Sharif University of Technology Varchandi, Sahar (Author) ; Akbari Jokar, Mohammad Resa (Supervisor) ; Memari, Ashkan (Co-Supervisor)
    Abstract
    Today, with the expansion of business relations at international levels, there are many organizations that operate in global supply chains. Activities at such levels face new types of challenges in various fields of "supply chain management" pillars, of which "supplier selection" is one of them. The possibility of unexpected events, the need to comply with environmental protection laws, as well as the need to take into account social considerations, are among the things that have increased by being in larger supply chains, making it challenging to provide the basic resources needed in such chains and forcing their managers to considering considerations other than what they have always... 

    Design of a Sustainable Supply Chain Network for Urban Spent Batteries

    , M.Sc. Thesis Sharif University of Technology Kalabi, Sogol (Author) ; Akbari Jokar, Mohammad Reza (Supervisor) ; Memari, Ashkan (Supervisor)
    Abstract
    This research addresses the design and optimization of a sustainable supply chain for an environmental startup, with a focus on the collection and recycling of urban alkaline batteries in Tehran. This problem is motivated by the lack of proper management of this type of waste, its environmental pollution, and the resulting loss of natural resources. The main concern is the optimal selection of metro stations to be equipped with collection boxes and the determination of the transportation and recycling network structure in such a way that the economic performance of the network (total profit/cost) is optimized while environmental impacts (carbon emissions) are controlled simultaneously. To... 

    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... 

    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... 

    Artificial intelligence for detection of external cervical resorption using label-efficient self-supervised learning method

    , Article Journal of Endodontics ; Volume 50, Issue 2 , 2024 , Pages 144-153.e2 ; 00992399 (ISSN) Mohammad-Rahimi, H ; Dianat, O ; Abbasi, R ; Zahedrozegar, S ; Ashkan, A ; Motamedian, S. R ; Rohban, M. H ; Nosrat, A ; Sharif University of Technology
    Elsevier  2024
    Abstract
    Introduction: The aim of this study was to leverage label-efficient self-supervised learning (SSL) to train a model that can detect ECR and differentiate it from caries. Methods: Periapical (PA) radiographs of teeth with ECR defects were collected. Two board-certified endodontists reviewed PA radiographs and cone beam computed tomographic (CBCT) images independently to determine presence of ECR (ground truth). Radiographic data were divided into 3 regions of interest (ROIs): healthy teeth, teeth with ECR, and teeth with caries. Nine contrastive SSL models (SimCLR v2, MoCo v2, BYOL, DINO, NNCLR, SwAV, MSN, Barlow Twins, and SimSiam) were implemented in the assessment alongside 7 baseline deep... 

    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...