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naderi-beni--mahdi
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Development of the Population Balance Code for Crystallization of Aluminium Hydroxide
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Fathollah (Supervisor) ; Movahedirad, Salman (Supervisor)
Abstract
Crystallization of Aluminum Hydroxide is the most important section of the Alumina production processes as the product yield and crystal size distribution (CSD) of this stage strongly affects the whole Alumina production process. In this work to simulate the crystallization in industrial steady precipitation tanks two Population Balance based models developed. First one is the Coupled CFD-Population Balance Model which considers the effects of flow hydrodynamics on crystallization kinetics and CSD. For development of this model the computational fluid dynamics software ANSYS FLUENT has been used. The two phase flow field has been simulated using Eulerian granular multiphase model coupled...
Effective Design and Implementation of Satellite Automatic Identification System (AIS) Receiver
, M.Sc. Thesis Sharif University of Technology ; Shabany, Mahdi (Supervisor)
Abstract
The Automatic Identification System (AIS) is designed to enhance maritime security and can be installed on ships, ground stations, and satellites. This system is used to transmit essential information from ships across four communication bands (two terrestrial bands and two satellite bands). The primary goal of this research is to receive all four communication bands through a satellite in a Low Earth Orbit (LEO). This goal faces two major challenges: the Doppler effect caused by the relative speed of the satellite to the ships and the significant distance of the satellite, which results in temporal signal interference due to the reception of a large volume of signals from ships. To address...
A fuzzy mixed integer linear programming model for integrating procurement-production-distribution planning in supply chain
, Article International Journal of Industrial Engineering Computations ; Volume 3, Issue 3 , 2012 , Pages 403-412 ; 19232926 (ISSN) ; Dehbari, S ; Tavakkoli Moghaddam, R ; Imenpour, A ; Naderi Beni, M ; Sharif University of Technology
2012
Abstract
In this paper, we study a supply chain problem where a whole seller/producer distributes goods among different retailers. Such problems are always faces with uncertainty with input data and we have to use various techniques to handle the uncertainty. The proposed model of this paper considers different input parameters such as demand, capacity and cost in trapezoid fuzzy forms and using two ranking methods, we handle the uncertainty. The results of the proposed model of this paper have been compared with the crisp and other existing fuzzy techniques using some randomly generated data. The preliminary results indicate that the proposed models of this paper provides better values for the...
Design of a Desalination System with High Recovery Using Membrane Based Systems
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Ali (Supervisor) ; Nouri Borujerdi, Ali (Supervisor)
Abstract
Osmotically assisted reverse osmosis (OARO) assimilates high efficiency due to non-thermal processes and accessing high salinity. This makes it suitable for high water recovery for the purpose of zero- and minimal liquid discharge desalination. Moreover, forward osmosis (FO) has low fouling efficiency which makes the operating costs of cleaning and replacement lower. This study aims at incorporating OARO and FO in a novel configuration with multiple inlet of the diluted draw solution to the regeneration section. Pinch analysis with simplifying assumptions was carried out for FO and OARO standalone stages. The results showed that pinch point in FO resides either on the beginning or at the end...
Cell formation configuration using interval type-2 fuzzy interactional interests among workers
, Article International Journal of Operational Research ; Volume 30, Issue 2 , 2017 , Pages 172-192 ; 17457645 (ISSN) ; Mahdavi Amiri, N ; Naderi, F ; Mahdi, M ; Sharif University of Technology
Inderscience Enterprises Ltd
2017
Abstract
Group working has an important role in cellular manufacturing systems (CMS) as they can affect the work environment and job executions on machines. The most important factors affecting human resources are aspects of ability and interactional interest among workers in workshops. Here, we present a simple and efficient method considering these two aspects to deal with the assignment of workers to cells. We use interval type-2 fuzzy interactional interest among workers and the capability of working on machines to develop a new concept of cell formation in CMS. By using a multidepot multiple travelling salesman problem (MDmTSP) model, we assign workers to cells and then propose a mathematical...
Consistent arbitrary Lagrangian Eulerian formulation for large deformation thermo-mechanical analysis
, Article Materials and Design ; Volume 31, Issue 8 , 2010 , Pages 3690-3702 ; 02641275 (ISSN) ; Movahhedy, M. R ; Sharif University of Technology
2010
Abstract
Arbitrary Lagrangian Eulerian (ALE) method is widely used for simulation of large deformation problems, such as metal forming. However, in many such applications, modeling of the heat generation and transfer in conjunction with the stress analysis is necessary. In this work, a fully coupled dynamic ALE formulation is developed. The ALE form of energy balance equation is derived, and is coupled with the dynamic, rate dependent ALE stress analysis. The proposed formulation is used for simulation of a few thermo-mechanical problems. The effectiveness and efficiency of the ALE method is verified by comparing the results of this simulation with available experimental and numerical results
Privacy Preserving Access Control in IoT for eHealth
, M.Sc. Thesis Sharif University of Technology ; Amini, Morteza (Supervisor)
Abstract
One of the applications of Internet of things (IoT) is its usage in the eHealth area. Various types of sensors (e.g., sensor to measure heart health, blood sugar levels, and respiratory) exist that not only provide required information for patients, but also send the health information to hospital staff through the network. Leveraging this technology in various intensive care units of hospital facilitate nurses and medical staff in monitoring of patients. However, moving towards these environments leads to new security challenges. One of the most important challenges is controlling access to sensors’ data and preserving patients privacy so that doctor and nurses should access patients’...
On comparison of three multi-feed osmotic-mediation-based configurations for brine management: Techno-economic optimization and exergy analysis
, Article Desalination ; Volume 525 , 2022 ; 00119164 (ISSN) ; Ghofrani, I ; Moosavi, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This study aims at analyzing the performance of three units known as low salt rejection reverse osmosis (LSRRO), split-feed counterflow reverse osmosis (SF-CFRO), and split-brine counterflow reverse osmosis (SB-CFRO) and implementing them in a modified multi-stage multi-feed counter-current membrane with cascade recycle for dewatering hypersaline streams to the salinity appropriate for crystallizers' feed. Exergy and primitive pinch analysis showed that dewatering is limited in SF-CFRO as the permeate inlet dictates the maximum salinity difference at the pinch point as well as high frictional pressure loss in the permeate channel. SB-CFRO and LSRRO units can reach high salinities by...
Investigation of partial discharge propagation and location in multiple-α and single- α transformer windings using optimized wavelet analysis
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 30, Issue 6 , 2006 , Pages 655-666 ; 03601307 (ISSN) ; Vakilian, M ; Blackburn, T. R ; Phung, T. B ; Salay Naderi, M ; Sharif University of Technology
2006
Abstract
Partial discharges (PD) are recognized as the main cause of the inner insulation deterioration process in power transformers. Therefore, the optimum inner insulation design is one of the challenges a transformer designer is faced with. Transformer strength, especially during transient conditions, is a criterion for transformer insulation designers. This challenge has made designers initiate and employ other types of winding, for example, rather than ordinary layer and disc windings employ the multiple-α windings. Multiple-α windings have a more complicated structure and are comprised of various parts with different physical structures and electrical characteristics. Typical partial discharge...
A complete treatment of thermo-mechanical ale analysis; Part 2: Finite element equations and applications
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 34, Issue 2 , 2010 , Pages 149-165 ; 10286284 (ISSN) ; Movahhedy, M. R ; Farrahi, G. H ; Sharif University of Technology
2010
Abstract
In the first part of this paper series, a complete formulation for fully coupled ALE analysis of large deformation solid mechanic problems was developed. The formulation incorporated inertial, rate and thermal effects, and the treatment of rate and temperature dependent constitutive equations were presented. In this part, the ALE equations are discretized to form finite element equations. An algorithm for the treatment of mesh motion is described and example problems are presented to demonstrate the capability of the proposed formulation
A complete treatment of thermo-mechanical ale analysis; Part I: Formulation
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 34, Issue 2 , 2010 , Pages 135-148 ; 10286284 (ISSN) ; Movahhedy, M. R ; Farrahi, G. H ; Sharif University of Technology
2010
Abstract
Arbitrary Lagrangian Eulerian (ALE) finite element method is extensively used for numerical simulation of solid mechanics problem. The versatility of the mesh in ALE approach makes it particularly effective and efficient in solving large deformation problems. In this work, a complete treatment of fully coupled ALE formulation is presented incorporating inertial, rate and thermal effects. The formulation may be used in conjunction with thermo-elasto-viscoplactic material models. A consistent and efficient tangent operator is developed in closed form to handle stress integration. The applications of this formulation are given in the second part of this paper
Rate-dependent dynamic ALE analysis of finite deformation of elasto-viscoplastic solids
, Article Materials and Design ; Volume 30, Issue 8 , 2009 , Pages 2995-3004 ; 02641275 (ISSN) ; Movahhedy, M. R ; Farrahi, G. H ; Sharif University of Technology
2009
Abstract
In this paper, formulation and implementation of finite element analysis within an Arbitrary Lagrangian Eulerian (ALE) description is presented for large deformation analysis of elasto-viscoplastic materials. The rate effects are included using a consistent procedure. An implicit algorithm with backward Euler integration scheme is used to integrate the elasto-viscoplastic constitutive equations. Also, the closed form of the consistent tangent operator is derived using the momentum balance equation to reduce the computation time. A fully coupled ALE procedure is used which includes dynamic effects. The proposed algorithm is implemented in an ALE code and its effectiveness and efficiency is...
Synthesis and characterization of new triphenylamine-based dyes with novel anchoring groups for dye-sensitized solar cell applications
, Article Journal of Materials Science: Materials in Electronics ; Volume 28, Issue 2 , 2017 , Pages 1859-1868 ; 09574522 (ISSN) ; Hosseinzadeh, B ; Azari, M ; Ghahary, R ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Three new chromophores based on the triphenylamine (MM, DM, DN) with various novel electron withdrawing anchoring groups have been synthesized for use in dye-sensitized solar cells (DSSCs). The sensitizers were characterized by 1H and 13C NMR, Mass, UV–Vis, and electrochemical analysis. The HOMO and LUMO electron distributions of the sensitizers were calculated using density functional theory on a B3LYP level for geometry optimization. The DSSC device based on DM dye showed the best photovoltaic performance among MM and DN dyes: maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 98 %, short circuit current (JSC) of 4.58 mA/cm2, open circuit voltage (VOC) of...
Preparation of cobalt-ruthenium nanocatalysts supported on nitrogen-doped graphene aerogel and carbon nanotubes in Fischer-Tropsch synthesis
, Article Arabian Journal of Chemistry ; Volume 16, Issue 8 , 2023 ; 18785352 (ISSN) ; Aghababai Beni, A ; Pournuroz Nodeh, Z ; Sharif University of Technology
Elsevier B.V
2023
Abstract
In this study, cobalt-ruthenium nanocatalysts supported on nitrogen-doped graphene aerogel (NGA) and carbon nanotubes (CNT) were synthesized using the wet impregnation method for Fischer-Tropsch process with a cobalt to ruthenium ratio of 1:50. The synthesized catalysts underwent various characterizations such as FTIR, ICP, BET, XRD, EDX, TPR and TEM. The performance of the synthesized catalysts was compared to that of a cobalt-ruthenium nanostructured catalyst supported on NGA and CNTs. The catalysts were evaluated in a fixed-bed reactor at 25 bar, with a gas ratio H2/CO: 2 and Gas Hourly Space Velocity (GHSV) 10,000 mlg-1h-1, at temperatures of 260 °C and 280 °C. The use of NGA as a cobalt...
Aberrations in temporal dynamics of cognitive processing induced by Parkinson’s disease and Levodopa
, Article Scientific Reports ; Volume 13, Issue 1 , 2023 ; 20452322 (ISSN) ; Heidari Beni, M. H ; Aghajan, H ; Sharif University of Technology
Nature Research
2023
Abstract
The motor symptoms of Parkinson's disease (PD) have been shown to significantly improve by Levodopa. However, despite the widespread adoption of Levodopa as a standard pharmaceutical drug for the treatment of PD, cognitive impairments linked to PD do not show visible improvement with Levodopa treatment. Furthermore, the neuronal and network mechanisms behind the PD-induced cognitive impairments are not clearly understood. In this work, we aim to explain these cognitive impairments, as well as the ones exacerbated by Levodopa, through examining the differential dynamic patterns of the phase-amplitude coupling (PAC) during cognitive functions. EEG data recorded in an auditory oddball task...
Identify initial nodes for spreader in a new diffusion model based on topology (dbt) in social networks
, Article 2023 9th International Conference on Web Research, ICWR 2023 ; 2023 , Pages 52-57 ; 979-835039969-1 (ISBN) ; Yazdanifar, F ; Salimi, N ; Ahmadi Beni, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
With the development of science and technology through social networks, the process of diffusion has become a controversial subject. In social networks, the process of diffusion is transmitted from one individual to another. The influence maximization problem, in which at least k nodes are chosen as the initial nodes of the spreader in the smallest amount of time, is one of the most critical aspects of the diffusion process. Furthermore, the initial nodes in the social network should generate the most influence on the other nodes in the network. However, in the algorithms proposed to solve the problem of influence maximization, the real-world factors which affect the influence probability in...
Permutation flowshops in group scheduling with sequence-dependent setup times
, Article European Journal of Industrial Engineering ; Volume 6, Issue 2 , 2012 , Pages 177-198 ; 17515254 (ISSN) ; Salmasi, N ; Sharif University of Technology
2012
Abstract
This paper focuses on the flow shop sequence dependent group scheduling (FSDGS) problem with minimisation of total completion time as the criterion (Fm|f mls, prmu, S plk|ΣC j). The research problem is formulated in form of two different mixed integer linear programming (MILP) models. Comparing with the latest MILP model for the proposed problem in the literature, the complexity size of the proposed models are significantly reduced. One of the proposed mathematical models is so effective that even medium-sized instances (problems up to 60 jobs in all groups) are solved to optimality in a reasonable amount of time. Moreover, a metaheuristic hybridising genetic and simulated annealing...
Nickel molybdate nanorods supported on three-dimensional, porous nickel film coated on copper wire as an advanced binder-free electrode for flexible wire-type asymmetric micro-supercapacitors with enhanced electrochemical performances
, Article Journal of Colloid and Interface Science ; Volume 542 , 2019 , Pages 325-338 ; 00219797 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Academic Press Inc
2019
Abstract
Wire-shaped micro-supercapacitors attracted extensive attentions in next-generation portable and wearable electronics, due to advantages of miniature size, lightweight and flexibility. Herein, NiMoO 4 nanorods supported on Ni film coated Cu wire are successfully fabricated thorough direct deposition of Ni film onto Cu wire as the conductive substrate, followed by growth of the NiMoO 4 nanorods on Ni film coated Cu wire substrate by means a hydrothermal annealing process. The prepared 3D, porous electrode demonstrates extremely high areal specific capacitance of 12.03F cm −2 at the current density of 4 mA cm −2 and retained capacitance of 8.23 F cm −2 at a much higher current density of 80...
Nickel vanadium sulfide grown on nickel copper phosphide dendrites/Cu fibers for fabrication of all-solid-state wire-type micro-supercapacitors
, Article Chemical Engineering Journal ; Volume 392 , 15 July , 2020 ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Herein, we have successfully fabricated NiVS/NiCuP nanostructures on Cu wire as a fiber electrode for high performance FSMSCs applications. The 3D NiCuP dendritic film was firstly deposited on Cu wire through the electrodeposition method, which not only act as a scaffold for deposition of the electroactive materials (NiV-LDH and NiV-S), but also served as a micro-porous current collector, supplied extra capacitances. Then, NiV-LDH nanosheets grown on 3D NiCuP film were obtained using a hydrothermal method. The sulfidation of NiV-LDH is carried out through an ion-exchange reaction of OH– with S2– to obtain NiVS, which maintains an ultrathin and porous structure, improves the electrical...
Cobalt vanadium chalcogenide microspheres decorated with dendrite-like fiber nanostructures for flexible wire-typed energy conversion and storage microdevices
, Article Nanoscale ; Volume 14, Issue 25 , 2022 , Pages 9150-9168 ; 20403364 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
The increasing energy demand for next-generation portable and miniaturized electronics has drawn tremendous attention to develop microscale energy storage and conversion devices with light weight and flexible characteristics. Herein, we report the preparation of flower-like cobalt vanadium selenide/nickel copper selenide (CoVSe/NiCuSe) microspheres with three-dimensional hierarchical structure of micropore growth on copper wire for a flexible fiber microsupercapacitor (microSC) and overall water splitting. The CoV-LDH microspheres are anchored on the dendrite-like NiCu nanostructured Cu wire using a hydrothermal method (CoV-LDH/NiCu@CW). The sulfidation and selenization of CoV-LDH/NiCu was...