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Holistic performance management of virtual teams in third-party logistics environments
, Article Team Performance Management ; Volume 24, Issue 3-4 , 2018 , Pages 186-202 ; 13527592 (ISSN) ; Abdekhodaee, A ; Najmi, M ; Arab Maki, A ; Sharif University of Technology
Emerald Group Publishing Ltd
2018
Abstract
Purpose: The purpose of this paper is to investigate the use of an integrated approach for performance improvement of virtual teams (VTs) in third-party logistics (3PL) through the integration of performance management (PM), visual management (VM) and continuous improvement (CI) initiatives into one coherent system. The paper will also propose a methodological framework to establish such a system. The intended integrated system is called as integrated visual management (IVM) throughout this paper. Design/methodology/approach: This research is based on a case study that took place in a 3PL context with 19 VTs of different sizes spread across Australia. Many major 3PL companies provide their...
Remedial effects of metal oxide nanoparticles to treat suspension transport in saturated porous media
, Article SPE - European Formation Damage Conference, Proceedings, EFDC ; Volume 1 , 2013 , Pages 478-488 ; 9781627486101 (ISBN) ; Pourafshary, P ; Ayatollahi, S ; Habibi, A ; Sharif University of Technology
2013
Abstract
Hydrocarbon production decline as a result of formation damage caused by fines migration has been widely observed in laboratory corefloods and natural flows in porous media. Permeability impairment due to fines migration is explained by different capture mechanisms of already released particles at some pore sites. Preventing detachment of in-situ particles from the rock surface during enhanced oil recovery (EOR) agent injection into the porous media has been reported recently. In this experimental study, the effect of five types of metal oxide nanoparticles; γ-AI2O3, ZnO, CuO, MgO and SiO: to adsorb the fine particles existing in the flowing suspension has been investigated. In each test,...
Evaluation of Aspergillus niger and Penicillium simplicissimum for their ability to leach Zn–Ni–Cu from waste mobile phone printed circuit boards
, Article Journal of Material Cycles and Waste Management ; Volume 24, Issue 1 , 2022 , Pages 83-96 ; 14384957 (ISSN) ; Esmaeili, A ; Yaghmaei, S ; Arab, B ; Sharif University of Technology
Springer Japan
2022
Abstract
In this research, Zn, Ni, and Cu recovery from mobile phone printed circuit boards was investigated. The initial pH and pulp density using Aspergillus niger or Penicillium simplicissimum fungi were optimized to improve the recovery of Zn, Ni, and Cu using a central composite design. Fungi were able to recover 97% of Cu. Often for Ni recovery, A. niger was more effective, but in low pulp densities and low pH, P. simplicissimum was preferred. For recovery of Zn, A. niger is more appropriate at pH lower than 6, but P. simplicissimum outperforms at pH higher than 6. Under the optimum conditions (pulp density of 4 gL−1 and initial pH 10), the respective recovery of Cu, Ni, and Zn was determined...
NETAL: A new graph-based method for global alignment of protein-protein interaction networks
, Article Bioinformatics ; Volume 29, Issue 13 , 2013 , Pages 1654-1662 ; 13674803 (ISSN) ; Khadem, A ; Hashemifar, S ; Arab, S. S ; Sharif University of Technology
2013
Abstract
Motivation: The interactions among proteins and the resulting networks of such interactions have a central role in cell biology. Aligning these networks gives us important information, such as conserved complexes and evolutionary relationships. Although there have been several publications on the global alignment of protein networks; however, none of proposed methods are able to produce a highly conserved and meaningful alignment. Moreover, time complexity of current algorithms makes them impossible to use for multiple alignment of several large networks together.Results: We present a novel algorithm for the global alignment of protein-protein interaction networks. It uses a greedy method,...
Cavity quantum electrodynamics in the ultrastrong coupling regime
, Article Scientia Iranica ; Volume 18, Issue 3 F , June , 2011 , Pages 820-826 ; 10263098 (ISSN) ; Chalabi, H. R ; Arab, A ; Khorasani, S ; Sharif University of Technology
2011
Abstract
We revisit the mathematical formulation of the famous Jaynes-Cummings-Paul Hamiltonian, which describes the interaction of a two-level atom with a single mode of an electromagnetic cavity reservoir. We rigorously show that under the condition of ultrastrong coupling between the atom and cavity in which the transition frequency is comparable to the coupling frequency, the bosonic field operators undergo non-sinusoidal time variations. As a result, the well-known solutions to the Jaynes-Cummings-Paul model are no longer valid, even when the rotating wave approximation is not used. We show how a correct mathematical solution could be found instead
Evaluation of aspergillus niger and penicillium simplicissimum for their ability to leach Zn–Ni–Cu from waste mobile phone printed circuit boards
, Article Journal of Material Cycles and Waste Management ; 2021 ; 14384957 (ISSN) ; Esmaeili, A. R ; Yaghmaei, S ; Arab, B ; Sharif University of Technology
Springer Japan
2021
Abstract
In this research, Zn, Ni, and Cu recovery from mobile phone printed circuit boards was investigated. The initial pH and pulp density using Aspergillus niger or Penicillium simplicissimum fungi were optimized to improve the recovery of Zn, Ni, and Cu using a central composite design. Fungi were able to recover 97% of Cu. Often for Ni recovery, A. niger was more effective, but in low pulp densities and low pH, P. simplicissimum was preferred. For recovery of Zn, A. niger is more appropriate at pH lower than 6, but P. simplicissimum outperforms at pH higher than 6. Under the optimum conditions (pulp density of 4 gL−1 and initial pH 10), the respective recovery of Cu, Ni, and Zn was determined...
P 134 – Absence of the patella has minimal effects on sagittal plane gait parameters
, Article Gait and Posture ; Volume 65 , 2018 , Pages 462-464 ; 09666362 (ISSN) ; Khandan, A ; Arab Baniasad, M ; Darbandi, H ; Vafaei, A. R ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Patella is the latest addition to the animal's skeleton. It's role in normal walking has not been clearly defined. A 9-year-old girl with congenital absence of the patella was assessed using instrumented gait analysis. The results show a tendency for the limb for external rotation, which is more pronounced during swing. We suggest that the role of the patella is mainly to redirect the force of the quadriceps tendon medially. The classically described role, which is to increase the lever arm of the quadriceps tendon, was not confirmed in this study. © 2018 Elsevier B.V
Experimental Study of Oxygen Reduction Reaction (ORR) on Cu-alloys, Electrocatalysts in Alkaline Solution and Theoretical Investigation of Oxygen Adsorption on Cu-alloys Nano-clusters
, Ph.D. Dissertation Sharif University of Technology ; Gobal, Fereydoon (Supervisor)
Abstract
In this study, electrochemical oxygen reduction reaction (ORR) was studied on Cu, Pd, Rh, Pd-Cu and Rh-Cu alloys in alkaline solution. Pd-Cu and Rh-Cu alloys were prepared by electrochemical methods. On copper electrode it is found that direct oxygen reduction is accompanied by the electrochemical reductions of copper oxides. Also, mechanism and kinetics of reaction change as the amount of copper oxides increase on the surface. For electrodeposited alloys, it is indicated that the reactivity of Pd-Cu and Rh-Cu alloys toward oxygen reduction is higher than pure Pd and pure Rh. The maximum reactivity among Pd-Cu alloys is related to the sample with 24.5% copper content while the maximum...
Cavity Quantum Electro-Dynamics in Ultra-Strong Coupling Regime
,
M.Sc. Thesis
Sharif University of Technology
;
Khorasani, Sina
(Supervisor)
Abstract
Cavity Quantum Electro-Dynamics (CQED) in Weak, Strong and Ultra-Strong coupling Regimes are studied. A MATLAB m-file is written which is able to solve any arbitrary CQED configuration. This program demands input data such as number of Quantum Dots, number of energy levels of each Quantum Dot, energies of each energy level of Quantum Dots, Number of cavity modes, eign-frequency of each cavity mode, coupling constant, dipole strength of each allowed transition of Quantum Dots and initial state of system from user and begins to solve the Schrodinger equation for annihilation and atomic ladder operators. In addition, coefficients of each possible ket will be calculated. Since, any approximation...
Fermionic Approach To The One Dimensional Kondo Necklace Model
, M.Sc. Thesis Sharif University of Technology ; Langari, Abdollah (Supervisor)
Abstract
Strongly correlated materials are kind of materials in which novel electric and magnetic properties will appear as a result of strong correlations among their electrons like “heavy fermion materials”. Kondo lattice model is a model to describe heavy fermion materials. If we are merely interested in the magnetic properties of heavy fermions we can replace the Kondo lattice Model with the simpler model called the Kondo-necklace model which consists of the interactions only among the spins of the itinerant (conduction) and localized electrons (magnetic impurities) and also the interactions between the spins of the itinerant electrons. In this thesis we investigate the properties of the one...
Synthesis and Characterization of Bis[2-(2׳-Hydroxyphenyl)- -oxazolinato]Ni(II) Complex and Investigation of it׳s Catalytic Activity in C-C Coupling Heck Reaction
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this study a new Ni(II)-¬oxazoline complex was synthesized by reaction of Ni(CH3COO)2.4H2O and 2-(2׳-hydroxyphenyl)-2-oxazoline ligand in MeOH solvent. The resulting complex bis[2-(2׳-hydroxyphenyl)-2-oxazolinato]Ni(II), was characterized by different spectroscopic methods. X-ray diffraction showed that this complex is four coordinated with a square planner geometry. The complex was applied as an efficient homogeneous catalyst in C-C coupling Heck reaction of arylhalides with olefins such as methylacrylate. Investigation of the catalytic activity of the complex in Heck reaction between arylhalides and olefins showed high yield and selectivity. For example reaction between iodobenzene and...
Optimization of the Capability of Native Microorganisms Isolated from the Landfill of Electronic Wastes in Bioleaching of E-Waste
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
Given the complex structure of electronic waste and the difficulty of recycling it by traditional methods, the focus is mainly on biohydrometallurgy method, and in particular on bioleaching. To recover metals, various microorganisms are utilized in this method. In light of previous studies, cyanogenic bacteria have been widely used for the extraction of basic and precious metals. Among the species, indigenous microorganisms have a higher ability to resist toxic environments in the bioleaching of metals due to their adaptation by rapid changes in their metabolic system over time. The main objective of this study is to isolate indigenous microorganisms from electronic waste landfill for their...
Formulation and Properties of Scaffolds based on Hydroxyapatite Composites Containing Titanium Dioxide and Magnesium Oxide
, M.Sc. Thesis Sharif University of Technology ; Nemati, Ali (Supervisor)
Abstract
This study investigates the effect of titanium dioxide and magnesium oxide additives on hydroxyapatite synthesized by sol-gel and composite with the predominant phase of hydroxyapatite by in situ method to improve mechanical properties. Scaffold samples were synthesized with nanometer-sized hydroxyapatite and composite powder particles by gel casting and sintered at 1200 ° C. Then, to evaluate the synthesized powders, simultaneous thermal analysis (STA), X-ray diffraction test, FTIR test, FESEM, EDS, and MAP analysis were used. Also, to evaluate the mechanical properties of the scaffolds, a compressive test was used, and to evaluate the scaffolds' density, the Archimedes method was used....
Climate Change and Mortality: Evidence from Iran
, M.Sc. Thesis Sharif University of Technology ; Vesal, Mohammad (Supervisor)
Abstract
Due to the prominence of the evaluation of the consequences of rising temperatures, this paper examines the effects of temperature variation on mortality across different demographic groups in Iran. I use a rich weekly data set from 2009 to 2017 across different demographic groups to understand the potential health impacts of climate change in a developing country. Using several fixed effect regressions, I discover that for an additional day with a mean temperature over 25°C, mortality rate increases by 2.56% relative to the effects of an extra day in 0-5 °C, in the weekly temperature exposure horizon. I test for the harvesting effect by comparing the estimates at weekly and monthly...
Prediction of Flow Profiles in Different Well Layers using Fiber Optic Data Analysis
, M.Sc. Thesis Sharif University of Technology ; Bazargan, Mohammad (Supervisor)
Abstract
Downhole temperature measurement is one of the key tools for monitoring and analyzing the performance of production wells, evaluating water injection, and identifying multiphase flows within wells. The development of fiber optic technology and tools such as distributed temperature sensors has enabled the recording of high-resolution and detailed temperature profiles. These data, which measure temperature over a wide range along the wellbore, allow researchers to analyze complex downhole processes and identify fluid entry from various reservoir layers. However, accurately distinguishing the contribution of each layer to the total flow rate, especially under multiphase flow conditions and...
Formulation of soil angle of shearing resistance using a hybrid GP and OLS method
, Article Engineering with Computers ; Volume 29, Issue 1 , September , 2013 , Pages 37-53 ; 01770667 (ISSN) ; Alavi, A.H ; Mollahasani, A ; Gandomi, A. H ; Arab Esmaeili, M ; Sharif University of Technology
2013
Abstract
In the present study, a prediction model was derived for the effective angle of shearing resistance (φ′) of soils using a novel hybrid method coupling genetic programming (GP) and orthogonal least squares algorithm (OLS). The proposed nonlinear model relates φ′ to the basic soil physical properties. A comprehensive experimental database of consolidated-drained triaxial tests was used to develop the model. Traditional GP and least square regression analyses were performed to benchmark the GP/OLS model against classical approaches. Validity of the model was verified using a part of laboratory data that were not involved in the calibration process. The statistical measures of correlation...
A facile approach for reducing the working voltage of Au/TiO2/Au nanostructured memristors by enhancing the local electric field
, Article Nanotechnology ; Volume 29, Issue 1 , 2018 ; 09574484 (ISSN) ; Ebrahimi, M ; Bagheri Shouraki, S ; Moshfegh, A. Z ; Sharif University of Technology
Institute of Physics Publishing
2018
Abstract
Memristor devices have attracted tremendous interest due to different applications ranging from nonvolatile data storage to neuromorphic computing units. Exploring the role of surface roughness of the bottom electrode (BE)/active layer interface provides useful guidelines for the optimization of the memristor switching performance. This study focuses on the effect of surface roughness of the BE electrode on the switching characteristics of Au/TiO2/Au three-layer memristor devices. An optimized wet-etching treatment condition was found to modify the surface roughness of the Au BE where the measurement results indicate that the roughness of the Au BE is affected by both duration time and...
A data mining approach to compressive strength of CFRP-confined concrete cylinders
, Article Structural Engineering and Mechanics ; Volume 36, Issue 6 , Dec , 2010 , Pages 759-783 ; 12254568 (ISSN) ; Alavi, A. H ; Gandomi, A. H ; Arab Esmaeili, M ; Gandomi, M ; Sharif University of Technology
2010
Abstract
In this paper, compressive strength of carbon fiber reinforced polymer (CFRP) confined concrete cylinders is formulated using a hybrid method coupling genetic programming (GP) and simulated annealing (SA), called GP/SA, and a robust variant of GP, namely multi expression programming (MEP). Straightforward GP/SA and MEP-based prediction equations are derived for the compressive strength of CFRP-wrapped concrete cylinders. The models are constructed using two sets of predictor variables. The first set comprises diameter of concrete cylinder, unconfined concrete strength, tensile strength of CFRP laminate, and total thickness of CFRP layer. The most widely used parameters of unconfined concrete...
Effect of Equal Channel Angular Pressing(ECAP) Parameters on Microstructure and Mechanical Properties of Strip Samples of AZ31 Mg Alloy
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh Changiz, Abbas (Supervisor)
Abstract
Equal Channel angular pressing (ECAP) is one of the most applicable Severe Plastic Deformation (SPD) Procedures which results in improvement of strength and ductility through grain refinement and an appropriate texture development. In this study, in order to achieve a proper orientation and microstructure, ECAP was performed in different routes and temperatures up to 4 passes on AZ31 magnesium alloy. Microstructure and mechanical properties were studied. X-ray diffraction analysis was performed to study the basal orientation variation and calculation of sub-grain size. In addition, cold rolling at room temperature was done on the fourth pass specimens, in order to study the effect of ECAP...
A No-Wait Flowshop Scheduling Problem with Sequence Dependent Setup Time
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
In this research a no-wait flowshop sequence dependent setup time scheduling problem with weighted earliness-tardiness penalties as the criterion (F_m |nwt,S_ijk |∑▒〖w_j^' E_j+w_j^" T_j 〗) is investigated. It is assumed that n jobs are assigned to a flowshop with m machines. The jobs are not allowed to wait between two successive machines according to no-wait requirement. Moreover each machine needs a setup time before processing a new job. The value of this setup time is dependent on the previous processed job on that machine.
A mixed integer linear programming model is proposed to solve the problem. As the problem is shown to be strongly NP-hard, a particle swarm optimization (PSO)...
A mixed integer linear programming model is proposed to solve the problem. As the problem is shown to be strongly NP-hard, a particle swarm optimization (PSO)...