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    Coordination in supply chain management

    , Article Supply Chain Sustainability and Raw Material Management: Concepts and Processes ; 2011 , Pages 52-74 ; 9781613505045 (ISBN) Sajadieh, M. S ; Bolooriarabani, A ; Sharif University of Technology
    2011
    Abstract
    The aim of this chapter is to review various perspectives on supply chain (SC) coordination issues and appreciate a range of coordination categories and mechanisms. The application of information technology in supply chain coordination (SCC) and the related cases are also studied in this chapter  

    Sole versus dual sourcing under order dependent lead times and prices

    , Article Computers and Operations Research ; Volume 36, Issue 12 , 2009 , Pages 3272-3280 ; 03050548 (ISSN) Sajadieh, M. S ; Eshghi, K ; Sharif University of Technology
    2009
    Abstract
    In this paper, we consider a dual-sourcing model with constant demand and stochastic lead times. Two suppliers may be different in terms of purchasing prices and lead-time parameters. The ordering takes place when the inventory level depletes to a reorder level, and the order is split among two suppliers. Unlike previous works in the order splitting literature, the supply lead time between vendor and buyer as well as unit purchasing prices is considered to be order quantity dependent. The proposed model finds out the optimal reorder point, order quantity and splitting proportion, using a solution procedure. Numerical results show that neglecting the relationship between ordering batch size... 

    Optimizing a joint economic lot sizing problem with price-sensitive demand

    , Article Scientia Iranica ; Volume 16, Issue 2 E , 2009 , Pages 159-164 ; 10263098 (ISSN) Akbari Jokar, M. R ; Sheikh Sajadieh, M ; Sharif University of Technology
    2009
    Abstract
    This paper considers the problem of a vendor-buyer integrated production-inventory model. The vendor manufactures the item at a finite rate and delivers the final goods at a lot-for-lot shipment policy to the buyer. We relax the assumption of uniform demand in the hitherto existing joint economic lot sizing models and analyze the problem where the end customer demand is price-sensitive. The relation between demand and price is considered to be linear. The model proposed, based on the integrated expected total relevant profits of both buyer and vendor, finds out the optimal values of order quantity and mark-up percentage, using an analytical approach. Some numerical examples are also used to... 

    Concurrent project scheduling and material planning: a genetic algorithm approach

    , Article Scientia Iranica ; Volume 16, Issue 2 E , 2009 , Pages 91-99 ; 10263098 (ISSN) Sheikh Sajadieh, M ; Shadrokh, S ; Hassanzadeh, F ; Sharif University of Technology
    2009
    Abstract
    Scheduling projects incorporated with materials ordering results in a more realistic problem. This paper deals with the combined problem of project scheduling and material ordering. The purpose of this paper is to minimize the total cost of this problem by determining the optimal values of activity duration, activity finish time and the material ordering schedule subject to constraints. We employ a genetic algorithm approach to solve it. Elements of the algorithm, such as chromosome structure, unfitness function, crossover, mutation and local search operations are explained. The results of the experimentation are quite satisfactory  

    Analyzing the supply chain using SCOR model in a steel producing company

    , Article 40th International Conference on Computers and Industrial Engineering, 25 July 2010 through 28 July 2010 ; 2010 ; 9781424472956 (ISBN) Seifbarghy, M ; Akbari, M. R ; Ssheikh Sajadieh, M ; Sharif University of Technology
    2010
    Abstract
    Supply Chain Operations Reference (SCOR) model is developed and maintained by the Supply Chain Council (SCC). The model is a reference model which can be used to map, benchmark and improve the supply chain operations. SCOR model provides companies with a basic process modeling tool, an extensive benchmark database and defines a set of supply chain metrics. Mobarakeh Steel Company (located in Isfahan, Iran) initiated the project of studying and analyzing its supply chain performance based on the SCOR model. This paper explains the steps and the results of the project. Interviews with the managers and considering the documents on the four major subjects of planning, logistics, information flow... 

    Developing a coordinated vendor-buyer model in two-stage supply chains with stochastic lead-times

    , Article Computers and Operations Research ; Volume 36, Issue 8 , 2009 , Pages 2484-2489 ; 03050548 (ISSN) Sheikh Sajadieh, M ; AkbariJokar, M. R ; Modarres, M ; Sharif University of Technology
    2009
    Abstract
    This paper develops an approach to determine the optimal production and shipment policy for an integrated vendor-buyer problem. The vendor manufactures the product in batches at a finite rate and ships the output to the buyer. All shipments to the buyer are equal-sized batches. Despite previous papers in the literature, we assume that the supply lead-time between vendor and buyer is stochastic and shortage is also allowed. The objective is to minimize the expected total cost of both buyer and vendor. We derive the expected annual integrated total cost function and propose an analytic solution procedure to determine the optimal policy. To illustrate the significance of cost-reduction of the... 

    Optimizing shipment, ordering and pricing policies in a two-stage supply chain with price-sensitive demand

    , Article Transportation Research Part E: Logistics and Transportation Review ; Volume 45, Issue 4 , 2009 , Pages 564-571 ; 13665545 (ISSN) Sheikh Sajadieh, M ; Akbari Jokar, M. R ; Sharif University of Technology
    Elsevier Ltd  2009
    Abstract
    In this paper we focus on a two-stage supply chain consisting of one vendor and one buyer. We develop an integrated production-inventory-marketing model to determine the relevant profit-maximizing decision variable values. The model proposed is based on the joint total profit of both the vendor and the buyer, and it finds out the optimal ordering, shipment and pricing policies. We are able to ascertain the optimal decision variable values employing an analytical solution procedure. The numerical evidence suggests that it is more beneficial for the buyer and the vendor to cooperate with each other when the demand is more price sensitive. © 2008 Elsevier Ltd. All rights reserved  

    An integrated vendor-buyer cooperative model under stochastic supply lead-time

    , Article International Journal of Advanced Manufacturing Technology ; Volume 41, Issue 9-10 , 2009 , Pages 1043-1050 ; 02683768 (ISSN) Sheikh Sajadieh, M ; Akbari Jokar, M. R ; Sharif University of Technology
    2009
    Abstract
    This paper presents a single-vendor, single-buyer integrated inventory model. We relax the assumption of deterministic lead-time in the hitherto existing joint economic lot sizing (JELS) models and analyze the problem where the buyer lead-time is a stochastic variable. Moreover, we consider the situation in which shortage is allowed. The vendor produces the product in batches and periodically delivers final goods at a fixed lot size to the customer, who has a constant demand rate. The proposed model, based on the integrated expected total relevant costs of both buyer and vendor finds out optimal values of reorder point, order quantity, and number of shipments, using a solution procedure.... 

    An integrated vendor-buyer model with stock-dependent demand

    , Article Transportation Research Part E: Logistics and Transportation Review ; Volume 46, Issue 6 , November , 2010 , Pages 963-974 ; 13665545 (ISSN) Sajadieh, M. S ; Thorstenson, A ; Akbari Jokar, M. R ; Sharif University of Technology
    2010
    Abstract
    We develop an integrated vendor-buyer model for a two-stage supply chain. The vendor manufactures the product and delivers it in a number of equal-sized batches to the buyer. The items delivered are presented to the end customers in a display area. Demand is assumed to be positively dependent on the amount of items displayed. The objective is to maximize total supply chain profit. The numerical analysis shows that buyer-vendor coordination is more profitable in situations when demand is more stock dependent. It also shows that the effect of double marginalization provides a link between the non-coordinated and the coordinated case  

    A Survey on Searchable Symmetric Encryption Schemes

    , M.Sc. Thesis Sharif University of Technology Sajadieh, Zahra Sadat (Author) ; Khazaei, Shahram (Supervisor)
    Abstract
    Using “Searchable Encryption” enables us to encrypt the data, while preserving the possibility of running search queries. One of the most important applications of the mentioned is in Cloud Storage. As users do not trust the Cloud space, they are not inclined to store their data on the Could. The solution to this problem is of course, Cryptography. However, ordinary Cryptography methods, eliminate the data’s searchability. Hence, we need encryption schemes that code the data while retaining their searchability. So far, various schemes has been proposed that differ in their performance, security level, and usage. In this thesis, we aim to discuss and analyze these methods  

    Developing a Joint Economic Lot Sizing (JELS) Model in Multi-Stage Supply Chains

    , Ph.D. Dissertation Sharif University of Technology Sheikh Sajadieh, Mohsen (Author) ; Akbari Jokar, Mohammad Reza (Supervisor)
    Abstract
    In this thesis, we develop seven integrated production-inventory models for two or three-stage supply chains under stochastic and/or dependent parameters. The problem is called Joint Economic Lot Sizing (JELS) and can be considered as the building block for wider supply chain systems. The first and the second researches deal with the problem in which the supply lead time between the vendor and the buyer is stochastic with uniform and exponential distribution, respectively. The numerical analyses shows that the cooperation between two partners is more critical in unpredictable purchasing environments in terms of stochastic lead-times. In the third research, we investigate four sourcing models... 

    Non-fragile control and synchronization of a new fractional order chaotic system

    , Article Applied Mathematics and Computation ; Volume 222 , 2013 , Pages 712-721 ; 00963003 (ISSN) Asheghan, M. M ; Delshad, S. S ; Hamidi Beheshti, M. T ; Tavazoei, M. S ; Sharif University of Technology
    2013
    Abstract
    In this paper, we address global non-fragile control and synchronization of a new fractional order chaotic system. First we inspect the chaotic behavior of the fractional order system under study and also find the lowest order (2.49) for the introduced dynamics to remain chaotic. Then, a necessary and sufficient condition which can be easily extended to other fractional-order systems is proposed in terms of Linear Matrix Inequality (LMI) to check whether the candidate state feedback controller with parameter uncertainty can guarantee zero convergence of error or not. In addition, the proposed method provides a global zero attraction of error that guarantees stability around all existing... 

    Parameters calculation of transformer winding detailed model based on finite element method to study partial discharge

    , Article International Review on Modelling and Simulations ; Volume 5, Issue 5 , October , 2012 , Pages 1995-2000 ; 19749821 (ISSN) Hosseini, S. M. H ; Vakilian, M ; Enjavimadar, S. M ; Sharif University of Technology
    Praise Worthy Prize  2012
    Abstract
    The first step to locate Partial Discharge in power transformers is to find a model that can clearly explain the behavior of the winding in high-frequency. The detailed model is one of the models used for the study of PD. One of the fundamental problems of the described model is to find its parameters. And the accuracy in calculating these parameters has significant impact on reducing the simulation error and PD locating. The current paper seeks to calculate the parameters of the detailed model 20kv distribution transformer winding by using the finite element method (FEM). Comparing the results of this model with pulse waveforms obtained from the PD to the winding in the laboratory... 

    A Mechanical model for flexible exercise bars to study the influence of the initial position of the bar on lumbar discs and muscles forces

    , Article Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS, 25 August 2015 through 29 August 2015 ; Volume 2015-November , 2015 , Pages 3917-3920 ; 1557170X (ISSN) ; 9781424492718 (ISBN) Khalaf, K ; Abdollahi, M ; Nikkhoo, M ; Hoviattalab, M ; Asghari, M ; Ashouri, S ; Nikpour, S ; Kahrizi, S ; Parnianpour, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Abstract
    A single-degree-of-freedom model is considered for flexible exercise bars based on the lumped-element approach. By considering the side segment of a flexible bar as a cantilever beam with an equivalent mass at the free end, its free-vibration response, as well as the forced response under the excitation of the grip, are expressed parametrically. Experiments are performed on a particular flexible bar (FLEXI-BAR) in order to obtain numerical values for quantifying the model's parameters. The model is also computationally simulated to study the response of the flexible bar to various excitations. The results are imported into a multi-segment musculoskeletal software (AnyBody), where the effect... 

    Magnetoelectric nanocomposite scaffold for high yield differentiation of mesenchymal stem cells to neural-like cells

    , Article Journal of Cellular Physiology ; Volume 234, Issue 8 , 2019 , Pages 13617-13628 ; 00219541 (ISSN) Esmaeili, E ; Soleimani, M ; Ghiass, M. A ; Hatamie, S ; Vakilian, S ; Zomorrod, M. S ; Sadeghzadeh, N ; Vossoughi, M ; Hosseinzadeh, S ; Sharif University of Technology
    Wiley-Liss Inc  2019
    Abstract
    While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe 2 O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through... 

    Hydrogenated graphene oxide (H-G-SiO2) Janus structure: Experimental and computational study of strong piezo-electricity response

    , Article Journal of Physics D: Applied Physics ; Volume 53, Issue 17 , 2020 Bidmeshkipour, S ; Alidoosti, M ; Hosseinzadeh, A ; Seyyedi, S. M. S ; Elahi, M ; Pourfath, M ; Mohajerzadeh, S ; Sharif University of Technology
    Institute of Physics Publishing  2020
    Abstract
    We have investigated the piezoelectric response of the hydrogenated graphene oxide (H-G-SiO2) stacks both experimentally and theoretically. The piezoresponse force microscopy method and density-functional theory (DFT) calculations were used to study the piezoresponse effect of this structure from both experimental and computational point of views. A mono-layer graphene, made by chemical vapour deposition method, is deposited on Si/SiO2 substrate and its surface is then functionalized with hydrogen atoms. The vertical piezoresponse, observed by piezoresponse force microscopy, is measured to be about 2146 pC N-1, that is comparable to the reported state of the art piezoelectric materials such... 

    An ultra-wideband 3-dB quadrature hybrid with multisection broadside stripline tandem structure

    , Article Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering ; Volume 77 LNICST , 2012 , Pages 672-681 ; 18678211 (ISSN) ; 9783642351549 (ISBN) Javadzadeh, S. M. H ; Majedi, S. M. S ; Farzaneh, F ; Sharif University of Technology
    2012
    Abstract
    Design of an Ultra-Wideband 3-dB quadrature (90°) Hybrid using ADS and HFSS softwares plus Measurement report are presented. Simultaneous Use of these two softwares lead to fast and accurate design procedure. The coupler is realized in broadside stripline and with the connection of coupled regions in tandem structure. The measured data agrees well with the expected values from simulations, and shows a good ultra wide bandwidth response over the frequency range of 1-10 GHz. Measurements showed an amplitude unbalance of ±1.5 dB, a phase unbalance of 90°±7° , and an isolation and a return loss characteristics of more than 14 dB over the frequency of 1 to 10 GHz  

    Broadside coupler Channels 1 to 10 GHz

    , Article Microwaves and RF ; Volume 51, Issue 1 , 2012 ; 07452993 (ISSN) Javadzadeh, S. M. H ; Majedi, S. M. S ; Farzaneh, F ; Sharif University of Technology
    2012

    Tensile deformation mechanisms at different temperatures in the Ni-base superalloy GTD-111

    , Article Journal of Materials Processing Technology ; Volume 155-156, Issue 1-3 , 2004 , Pages 1900-1904 ; 09240136 (ISSN) Sajjadi, S. A ; Nategh, S ; Isac, M ; Zebarjad, S. M ; Sharif University of Technology
    2004
    Abstract
    The Ni-base superalloy GTD-111 is employed in high-power stationary gas turbines because of its high temperature strength and oxidation resistance. The temperature dependence of the tensile behavior of GTD-111 has been studied by tensile tests in the temperature range of 25-900°C with a constant strain rate of 10-4s-1. The results showed an abnormal tensile property variation with increasing temperature. The yield strength decreased slightly with temperature up to about 650°C and then increased between 650 and 750°C. Above 750°C, a rapid decrease in the yield strength was found. The tensile strength showed a similar behavior except for its maximum that occurred at 650°C. The elongation... 

    Cell-imprinted substrates act as an artificial niche for skin regeneration

    , Article ACS Applied Materials and Interfaces ; Vol. 6, Issue. 15 , 2014 , Pages 13280-13292 ; ISSN: 19448244 Mashinchian, O ; Bonakdar, S ; Taghinejad, H ; Satarifard, V ; Heidari, M ; Majidi, M ; Sharifi, S ; Peirovi, A ; Saffar, S ; Taghinejad, M ; Abdolahad, M ; Mohajerzadeh, S ; Shokrgozar, M. A ; Rezayat, S. M ; Ejtehadi M. R ; Dalby, M. J ; Mahmoudi, M ; Sharif University of Technology
    2014
    Abstract
    Bioinspired materials can mimic the stem cell environment and modulate stem cell differentiation and proliferation. In this study, biomimetic micro/nanoenvironments were fabricated by cell-imprinted substrates based on mature human keratinocyte morphological templates. The data obtained from atomic force microscopy and field emission scanning electron microscopy revealed that the keratinocyte-cell-imprinted poly(dimethylsiloxane) casting procedure could imitate the surface morphology of the plasma membrane, ranging from the nanoscale to the macroscale, which may provide the required topographical cell fingerprints to induce differentiation. Gene expression levels of the genes analyzed...